Id. at *11-12 (internal citations omitted).
The court noted that there was no evidence that the plaintiff had actual knowledge of the agreement. “[T]he proximity or conspicuousness of the hyperlink alone is not enough to give rise to constructive notice . . . .” Id. at *14.
Judge. Judge Noonan delivered the opinion.
Appeal from the Central District of California, Judge Josephine L. Staton presiding.
Gretchen Carpenter (argued), and Brian R. Strange, of Strange & Carpenter, Los Angeles, California, for Plaintiff-Appellee.
Yesterday, in Vargas v. SAI Monrovia B, Inc., No. B237257, __ Cal. App. 4th __ (2d Dist. June 4, 2013), a putative class action, the Second District revisited its holding in Sanchez v. Valencia Holding Co., LLC, 201 Cal.App.4th 74 (2012), review granted March 21, 2012, S199119. In Sanchez the court held that a “Retail Installment Sale Contract” used to purchase an automobile is unconscionable and unenforceable. In Vargas, the court again concluded that the identical sale contract does not require the arbitration of disputes between a purchaser and a car dealer because it is permeated by unconscionability.
The arbitration provision, entitled, “ARBITRATION CLAUSE,” was on the back at the bottom of the page, outlined by a black box; the arbitration provision was the last provision in the Sale Contract concerning the purchase of the vehicle; a provision related to the assignment of the contract appeared below it. The buyers’ final signatures appeared near the bottom of the front side. The only signature line on the back was at the very bottom of the page; it required the seller’s signature to assign the contract to a third party.
The Second District ordered published today Serpa v. California Surety Investigations, Inc., et al., No. B237363, __ Cal. App. 4th __ (filed Mar. 21, 2013, modified Apr. 19, 2013). In Serpa, the Court of Appeal reversed the denial of a motion to compel arbitration.
At the trial court level, the court denied defendants’ motion to compel arbitration, finding the agreement to arbitrate lacked mutuality. Defendants argued that the requisite mutuality was provided by the bilateral arbitration provisions in the employee handbook, incorporated by reference into the arbitration agreement. The trial court rejected this argument because defendant could change the handbook at its sole discretion and without notice. The Second District reversed.
Because the agreement incorporated the arbitration policy in the employee handbook, the Court concluded that this “salvages the agreement by establishing an unmistakable mutual obligation on the part of [employer and plaintiff] to arbitrate ‘any dispute’ arising out of her employment.” Plaintiff argued that the while the arbitration policy in the handbook establishes a bilateral obligation to arbitrate, she insisted that the mutual obligation is illusory because, the employer is authorized to alter the terms of any policy contained in the handbook at its sole discretion and without notice. The Court disagreed, reasoning that the right to alter the terms was limited by the covenant of good faith and fair dealing implied in every contract.
In a tax day ruling that may have implications for co-defendants seeking to compel arbitration, the Second District affirmed a trial court’s denial of a motion to compel arbitration. Barsegian v. Kessler & Kessler, et al., No. B237044, __ Cal.App.4th __ (2d Dist. Apr. 15, 2013). Some defendants moved to compel arbitration, but the remaining defendants did not. Slip Op. at 2. The trial court denied on the grounds of waiver and the possibility of inconsistent rulings.
[N]ot every factual allegation in a complaint automatically constitutes a judicial admission. Otherwise, a plaintiff would conclusively establish the facts of the case by merely alleging them, and there would never be any disputed facts to be tried. . . . A judicial admission is therefore conclusive both as to the admitting party and as to that party’s opponent. (4 Witkin, Cal. Procedure (5th ed. 2008) Pleading, § 454, p. 587.) Thus, if a factual allegation is treated as a judicial admission, then neither party may attempt to contradict it—the admitted fact is effectively conceded by both sides.
Here, the moving defendants sought to reserve the right to argue at arbitration that the allegation of mutual agency was false, and thus it was not conceded by both sides.
Although the Kessler defendants frame their argument using the term “judicial admission” and rely on case law concerning judicial admissions, their counsel confirmed at oral argument that they do not in fact wish to treat Barsegian‟s allegation of mutual agency as a judicial admission, because the Kessler defendants do wish to be able to contest the truth of that allegation, either in court or before an arbitrator. That is, the Kessler defendants wish to hold Barsegian to the mutual agency allegation only for purposes of the motion to compel arbitration, but, should they succeed in compelling arbitration on the basis of that allegation, they wish to retain the right to prove to the arbitrator that the allegation is false. That is not how judicial admissions operate.
Yesterday, in a proposed wage and hour class action, the California Court of Appeal for the Second District reversed the lower court’s order granting a petition to compel arbitration. Compton v. Superior Court of Los Angeles County, No. B236669, — Cal.Rptr.3d —-, 2013 WL 1120619 (2d Dist. Mar 19, 2013). Plaintiff was a property manager who was required to sign an arbitration agreement that also barred arbitration of class claims. The trial court granted defendants’ petition to compel arbitration.
An order compelling arbitration is not appealable. (Elijahjuan v. Superior Court (2012) 210 Cal.App.4th 15, 19.) The parties argue over whether this matter is appealable under the “death knell” doctrine, which applies when an order effectively terminates a class action. Rather than parse the case law on that issue, we conclude that we have jurisdiction to treat this nonappealable order as a petition for writ of mandate in this unusual case because: (1) the unconscionability issue is one of law based on undisputed facts and has been fully briefed; (2) the record is sufficient to consider the issue and it appears that the trial court would be only a nominal party; (3) if we were to dismiss the appeal, and the ultimate reversal of the order is inevitable, it would come in a post-arbitration award after the substantial time and expense of arbitrating the dispute; and (4) as a result, dismissing the appeal would require the parties to arbitrate nonarbitrable claims and would be costly and dilatory.
The Court concluded that the arbitration agreement was unconscionably one-sided because (1) it exempted from arbitration claims the employer would more likely bring, such as claims for injunctive or equitable relief from trade secret disclosures; (2) it limited the time to demand arbitration to a period shorter than the relevant statutes of limitation; (3) it retained the statute of limitations period for itself and (4) it suggested that the arbitrator had the discretion not to award mandatory attorney’s fees under the Labor Code.
The California Court of Appeal struck down an arbitration agreement by a car dealer defendant in a putative class action, rejecting an argument that an unconscionability analysis that focuses on the lack of mutuality in an arbitration contract violates Concepcion. Natalini v. Import Motor, Inc., 213 Cal. App. 4th 587 (1st Dist., mod. February 5, 2013).
The Ninth Circuit Court of Appeals in a published opinion today, held that the Federal Arbitration Act broadly preempts state law invalidating class-action waivers in arbitration agreements, even where the waivers would preclude effective vindication of statutory rights. The opinion can be found here: http://www.ca9.uscourts.gov/datastore/opinions/2012/03/16/09-35563.pdf.
Editorial note: The author of California Class Action Law appeared for respondent Ajamian in the opinion summarized below, Ajamian v. CantorCO2e, L.P., et al.
In an opinion certified for publication, the First District Court of Appeal held that a broadly worded arbitration agreement that stated that “[a]ny disputes, differences or controversies arising under” a contract shall be settled by a panel of arbitrators was insufficient to establish “clear and unmistakable” evidence of an intent to delegate issues of enforceability or arbitrability to the arbitration panel. Ajamian v. CantorCO2e, L.P., et al., No. A131025 (1st Dist., Div. 5 Feb. 6, 2012) (available at http://www.courtinfo.ca.gov/opinions/documents/A131025.PDF).
Although the arbitration provision was broadly worded and indicated that arbitration might be conducted under the rules of an arbitration service that gives arbitrators the power to decide the validity of arbitration agreements, it did not provide clear and unmistakable evidence that the parties intended to delegate authority to the arbitrator, rather than to the court, to decide the threshold issue of whether the arbitration provision itself was unconscionable.
Plaintiff Ajamian filed a complaint against Defendants CantorCO2e and Margolis, asserting claims under the California’s Fair Employment and Housing Act, the California Labor Code, and other theories. Id. Defendants filed a petition to compel arbitration pursuant to the terms of a written employment agreement or, alternatively, an employee handbook. Id.
In an unpublished decision, the First District Court of Appeal affirmed the trial court’s denial of a motion to compel arbitration in a wage and hour class action, where defendants conducted voluminous discovery and filed and fully litigating two motions to compel further responses to discovery, a motion for sanctions and a motion for a protective order. Partridge, et al. v. Hott Wings, Inc., et al., No. A130266, 2012 WL 470458 (Feb. 14, 2012).
Between March 2010 and the October 2010 hearing on defendants’ motion to compel arbitration, defendants engaged in voluminous written discovery to which plaintiffs responded. In addition, defendants deposed numerous plaintiffs and third party witnesses. Although plaintiffs had begun deposing witnesses, they had not yet obtained basic documents from defendants through discovery. The discovery focused on the liability of individual defendants and the franchise defendants that employ plaintiffs. As a result of defendants’ discovery requests, plaintiffs provided information regarding plaintiffs’ estimated damages, which defendants were responsible for which violations, and the liability of the individual as well as the franchise defendants. A reasonable inference is that the information gained from defendants’ discovery goes to significant issues in plaintiffs’ case.
The Second District compelled a class action plaintiff to arbitrate his individual claims in Maiorano v. Professional Community Management, Inc., No. B220127, 2010 WL 3786721 (Cal. Ct. App. 2d Dist. Sept. 30, 2010). Defendant, Professional Community Management, Inc., appealed from an order denying its petition to compel arbitration of a putative class action filed by plaintiff, Ray A. Maiorano. Id. *1. The Second District held that “based solely on the parties’ agreement, we conclude they cannot be compelled to arbitrate on a class basis”, but it directed the trial court to compel arbitration of plaintiff’s individual claims. Id. The court reasoned that the “presence of a provision limiting arbitration to individual rather than joined or representative claims did not present a basis upon which the trial court could conclude the present arbitration agreement was permeated by an unlawful purpose.” Id. *4.


YELLOWSTONE COUNTY DETENTION FACILITY, SHERIFF MIKE LINDER, CAPTAIN SAM BOFTO, LIEUTENANT TIMOTHY NEITER, SERGEANT RANDY NAGEL, and OFFICER DAKOTA SING, Defendants.
FINDINGS AND RECOMMENDATIONS OF UNITED STATES MAGISTRATE JUDGE.
Timothy J. Cavan United States Magistrate Judge.
Plaintiff Colton Bulltail filed a Complaint alleging Defendants forced him to remain overnight in a cell with feces and urine on the floor in violation of the Eighth Amendment to the United States Constitution. The Complaint fails to state a claim upon which relief may be granted, and this matter should be dismissed.
Mr. Bulltail is a prisoner proceeding in forma pauperis so the Court must review his Complaint under 28 U.S.C. § 1915 and § 1915A. Sections 1915A(b) and 1915(e)(2)(B) require the Court to dismiss a complaint filed in forma pauperis and/or by a prisoner against a governmental defendant before it is served if it is frivolous or malicious, fails to state a claim upon which relief may be granted, or seeks monetary relief from a defendant who is immune from such relief. A complaint is frivolous if it "lacks an arguable basis either in law or in fact." Neitzke v. Williams, 490 U.S. 319, 325 (1989). "A case is malicious if it was filed with the intention or desire to harm another." Andrews v. King, 398 F.3d 1113, 1121 (9th Cir. 2005). A complaint fails to state a claim upon which relief may be granted if a plaintiff fails to allege the "grounds"'of his "entitlement to relief." Bell Atlantic Corp. v. Twombly, 550 U.S. 544, 555 (2007) (quotation omitted).
Rule 8 of the Federal Rules of Civil Procedure provides that a complaint "that states a claim for relief must contain ... a short and plain statement of the claim showing that the [plaintiff] is entitled to relief." Fed.R.Civ.P. 8(a)(2). That is, a complaint must "contain sufficient factual matter, accepted as true, to state a claim to relief that is plausible on its face." Ashcroft v. Iqbal, 556 U.S. 662, 678 (2009) (quotations omitted). A complaint's allegations must cross "the line from conceivable to plausible." Iqbal, 556 U.S. at 680.
There is a two-step procedure to determine whether a complaint's allegations cross that line. See Twombly, 550 U.S. at 556; Iqbal, 556 U.S. 662. First, the Court must identify "the allegations in the complaint that are not entitled to the assumption of truth." Iqbal, 556 U.S. at 679, 680. Factual allegations are not entitled to the assumption of truth if they are "merely consistent with liability," or "amount to nothing more than a 'formulaic recitation of the elements' of a constitutional" claim. Id. at 679, 681. A complaint stops short of the line between probability and the possibility of relief where the facts pled are merely consistent with a defendant's liability. Id. at 678.


text:
We report the use of ionic liquid based polymers for the conversion of epoxides into cyclic carbonates under ambient pressure (1.02 atm). The polymeric catalysts were prepared via thiol–ene click chemistry using trithiocyanuric acid (TTCA) and divinyl imidazolium-based ionic liquids in the presence of AIBN as a radical initiator under thermal conditions. TTCA acts as a planar C3 symmetric thiol molecule and helps in CO2 absorption due to the presence of a triazine moiety. Additionally, TTCA helps to achieve the optimum separation of catalytically active sites i.e. imidazolium bromide moieties. The resulting poly(ionic liquid) together with KI as a co-catalyst has been found to be very efficient for the conversion of a wide number of epoxide substrates into their corresponding cyclic carbonates under CO2 filled balloon conditions. The catalyst was able to retain its activity up to 6 cycles.
Global warming and climate change are the major problems in today's society. Excessive deforestation and fossil fuel burning result in a huge amount of carbon dioxide (CO2) accumulation in the atmosphere. Minimization of the excess amount of CO2 in the atmosphere is very much essential to control the drastic climate change.1 In fact, technological development has reached an extent where the separation of CO2 from the atmosphere has become possible.2 Recently, there have been immense research efforts to utilize the excess CO2 and convert it into chemicals and fuels.3 Moreover, CO2 can be efficiently utilised as a one-carbon (C1) source. One of the ways to utilize this excess CO2 is the conversion of epoxides to cyclic carbonates as they are very useful materials as highly polar aprotic solvents, monomers of polycarbonates, solvents for lithium ion batteries, core moieties of some drug molecules, etc.4 Industrial methods for the preparation of cyclic carbonates involve the use of highly corrosive phosgene as the C1 source. Moreover, hazardous hydrogen chloride is produced as one of the by-products.5 Replacement of phosgene with CO2 is also very advantageous due to its wide availability. There are many reports on the conversion of epoxides into cyclic carbonates using CO2. For example, salen–metal complexes, metalloporphyrins, metal organic frameworks, immobilized catalysts, modified molecular sieves, ion-exchange resins, quaternary ammonium salts, quaternary phosphonium salts, nitrogen-rich polymers, natural products, metal–crown ether complexes, g-C3N4 and zeolites were used as catalysts for conversion of epoxides into cyclic carbonates.6 However, one of the major problems associated with the epoxide to cyclic carbonate conversion is the requirement of high CO2 pressure.
One of the main difficulties in the activation of CO2 is its high thermodynamic stability and kinetic inertness.7 Consequently, it is necessary to develop efficient methods to perform the task under relatively less drastic conditions. In fact, there are few reports in the literature about the cyclic carbonate formation under atmospheric pressure.8 Thus, it is quite challenging to prepare cyclic carbonates from epoxides and CO2 under transition metal-free, solvent-free and ambient conditions and is also highly appreciated from the green chemistry viewpoint.
To achieve the goal of epoxide to cyclic carbonate conversion, our idea is to use ionic liquids (ILs) as they are highly efficient in absorbing CO2.9 Moreover, functionalised IL compounds are proven to be more efficient for epoxide to cyclic carbonate conversion as they provide additional stability to the intermediates produced during the reaction.10 However, the solubility of ILs in the reaction mixture is an issue during catalyst recovery after the completion of the reaction. To overcome this problem, heterogeneous polymeric IL-based materials were used as catalysts. However, the majority of previously reported poly(ionic liquid)-based materials were used under high CO2 pressure, which was the main disadvantage associated with them.11 Consequently, it is essential to introduce more reactivity by a proper choice of monomer during the synthesis. In fact, it is well established in the literature that two dimensional (2D) materials are highly efficient as heterogeneous catalysts due to their high surface area which results in excellent reactivity.12 For example, Gao and co-workers reported an IL-attached 2D covalent organic framework (COF) which efficiently reduces CO2 in the presence of silanes at 1 atmosphere pressure.13 Similarly, Dyson et. al. reported polyimidazolium based polymeric IL materials, which were able to convert epoxides under 1 atmospheric CO2 pressure.14 Additionally, Chen and co-workers also reported an IL-attached aluminium salen polymer which was efficient in bringing about cyclic carbonate conversion under 1 MPa pressure.15 In fact, there are many ILs composed of imidazolium salts having halide counter anions. The nucleophilicity of these halides plays an important role in the conversion as it initiates the reaction by opening up the epoxide ring.16 It has already been well established that quaternary ammonium iodide is able to provide excellent reactivity for the conversion but the major problem associated with it is its homogeneous nature. Our motivation was to use a cheap and heterogeneous iodide source i.e. KI for this purpose. For example, Werner and his group have used KI as a co-catalyst along with an amino alcohol as a homogeneous catalyst for epoxide to cyclic carbonate conversion.17a Similarly, Chen and co-workers used sugarcane bagasse as a heterogeneous catalyst and KI as a co-catalyst for the conversion of a wide number of substrates.17b Additionally, Liu and co-workers utilized KI as a co-catalyst in the presence of zinc-containing highly porous silica i.e. Zn-SBA-15.17c However, the above reports used high CO2 pressure for the epoxide to cyclic carbonate conversion. This motivated us to develop a suitable catalyst by combining KI and polymeric ILs. We expect that the catalytic efficiency of polymeric ILs would be enhanced in the presence of KI as a co-catalyst. We hope that this mixture would bring about the epoxide conversion under ambient CO2 pressure. To achieve this goal, our idea was to develop a thiol–ene click chemistry route for the polymerization of ILs. To enhance the reactivity, di-cationic ILs were chosen instead of the monocationic ones. Our strategy is to use a planar C3 symmetric triazine-containing thiol molecule like trithiocyanuric acid (TTCA). In fact, to our knowledge this is the first report where polymeric ILs are prepared via thiol–ene click chemistry using TTCA as the thiol source. Moreover, triazine-containing materials are reported to be effective for CO2 absorption and conversion.18 We expect that the planarity of TTCA may provide additional planarity to the target catalyst which is expected to enhance the reactivity (please see Fig. 1 and S1(a) in the ESI† for reaction schemes).
Fig. 1 Scheme illustrating the synthetic protocol for the catalyst preparation via thiol–ene click chemistry.
In this work, five dicationic ILs were used as starting materials and were prepared following the previous literature (see the Experimental section for details on IL synthesis).19 These materials were characterized by 1H and 13C NMR (Fig. S2 to S11, ESI†). The polymeric catalysts were prepared via thiol–ene click chemistry between 1,n-divinylimidazolium dibromides and TTCA in methanol, in the presence of AIBN as a radical initiator under thermal conditions (see the ESI† for details on polymer preparation).20 The polymeric catalysts were denoted as 1,n-IL-TTCA where “n” represents the number of carbon atoms present in the dibromoalkane moiety. The polymers were used as catalysts for the conversion of epoxides into cyclic carbonates in the presence of KI as a co-catalyst. This catalyst mixture was tested for a number of epoxides under CO2 filled balloon conditions.
All prepared polymers were characterized using solid-state 13C CP-MAS, TGA, PXRD, SEM, FTIR, TEM and CHN analyses. The presence of the imidazolium group, aliphatic carbon chain and triazine ring in all the samples was confirmed by 13C CP-MAS analysis. The peak corresponding to triazine appeared at 185 ppm which was also supported by the value obtained from ChemDraw. (Fig. S12 to S16, ESI†). Formation of the polymer was also supported by the TGA analysis under a N2 atmosphere. It was noted that all the polymeric materials are thermally stable up to 300 °C (Fig. S17, ESI†). Subsequently, 50% degradation was noted between 300 °C and 350 °C. The polymeric materials were found to be amorphous from the PXRD analysis (Fig. S18, ESI†). Surface morphology analysis using SEM reveals that the surface of all the polymers is rough in nature (Fig. S19, ESI†). The polymer formation was further verified using the FTIR analysis (see Fig. S20, ESI†). The absence of free S–H stretching at 2518 cm−1 and 2648 cm−1 suggests the complete conversion of thiol groups for the C–S bond formation. Additionally, the absence of the imine stretching peak (CN–H) near 2908 cm−1 (arising due to tautomerism) further confirms the polymer formation.21 Also, the above results confirm the absence of homo-polymerization of double bonds. We believe that the observed broadening of the C C stretching peak around 1645 cm−1 is due to the presence of some free double bonds owing to the use of excess monomers during the synthesis. For clarity, the FTIR spectra of the monomers are compared with those of 1,6-IL-TTCA and poly-1,6-IL and are shown in Fig. S20(b).† Moreover, the CHN analysis was performed for 1,6-IL-TTCA and the obtained percentages are 39.2%, 6.0% and 11.4% for C, H and N, respectively. Furthermore, the presence of sulfur and bromine was confirmed by elemental analysis during TEM measurement (see Fig. S21–S22 and Table S1†).
The above-mentioned polymer samples were utilized as catalysts for the conversion of epoxides into cyclic carbonates. All the reactions were performed under CO2 filled balloons. Epichlorohydrin was chosen as a model substrate to check the catalytic activity. We believe that the role of the triazine ring in the polymer is primarily to provide structural rigidity and secondarily to enhance CO2 absorption during the reaction. To check the reactivity for cyclic carbonate conversion, 50 mg of each polymer was used (Table 1, entry no. 7 to 11). It was observed that among other samples 1,6-IL-TTCA displays maximum conversion of epichlorohydrin into its corresponding cyclic carbonate (Table 1, entry no. 9). This may be due to the optimum separation of the active centres i.e. the imidazolium bromide moieties. We believe that the introduction of the long chain may introduce more hydrophobicity and lead to increased separation of active centres. This results in the lesser stabilization of the intermediates. When the amount of 1,6-IL-TTCA was further increased to 100 mg, the conversion increased up to 71% (Table 1, entry no. 13). To achieve complete conversion, salts like KI, KBr and KCl were used as co-catalysts. When KBr was used along with the polymer catalyst, 72% conversion was achieved, whereas 62% conversion was found in the case of KCl. It was also observed that individually the potassium halides are almost inactive for the conversion of epichlorohydrin (Table 1, entry no. 2, 4 & 5). Moreover, the 1,6-IL-TTCA and KI combination provided the complete conversion of epichlorohydrin (Table 1, entry no. 17) with a turnover number (TON) of 69.4. We believe that, during the reaction, some amount of cyclic carbonate was produced by the contribution of the polymer alone which slightly solubilises potassium halides. The extent of solubility of the potassium halides facilitates the anion exchange and the nucleophilicity and the good leaving group nature of the exchanged anions results in the difference in the conversion (Table 1, entry no. 15, 16 & 17).22 This hypothesis was further supported by the almost similar conversion in the case of KBr as a co-catalyst (Table 1, entry no. 15). Among the three halides, Cl− had the lowest nucleophilicity and the least efficient leaving group character. Thus the exchange of Cl− with Br−, from the polymer backbone, results in lower conversion compared to that obtained with the parent polymer alone (Table 1, entry no. 16 & 13). To find the optimum reaction conditions, the reaction time and temperature were also varied. In fact, a decrease in reaction time from 20 h and temperature from 105 °C resulted in a lower conversion (Table 1, entry no. 18 & 19). The results conclude that the 1,6-IL-TTCA and KI combination at 105 °C for 20 h are the optimum conditions. These conditions were used for the other epoxides (Table 1, entry no. 17).
a Conditions: substrate, epichlorohydrin 15 mmol; a CO2 filled balloon (1.02 atm, 99.5% pure, for balloon pressure measurement, see Fig. S23, ESI, & for the experimental set-up, see Fig. S24, ESI). Conversion was measured using 1H NMR spectroscopy.
To understand the reactivity of our catalyst, different functionalized epoxides were tested for cyclic carbonate conversion under the optimized reaction conditions. For example, allyl glycidyl ether, phenyl glycidyl ether, isopropyl glycidyl ether, glycidyl methacrylate and styrene oxide showed complete conversion (Table 2, entry no. 2 to 6). The observed reactivity is likely due to the presence of electronegative heteroatoms (e.g. oxygen or chloride), which help to stabilize the electron-rich intermediates produced during the reaction. In the case of styrene oxide, the phenyl rings help to stabilize the intermediates. However, 87% conversion was found in the case of (3-glycidyloxypropyl)trimethoxysilane. This slight decrease in conversion may be due to the bulkiness associated with the trimethoxysilane group (Table 2, entry 7). This phenomenon was further observed with t-butylglycidyl ether where only 50% conversion was observed (Table 2, entry 8). However, 1,2-epoxy-9-decene displayed 11% conversion which may be due to the presence of a much less polar carbon chain in the epoxide molecule (Table 2, entry 9). To check the efficiency of the catalyst, the study was extended to diepoxides. Conversion of diepoxides to corresponding cyclic carbonates is interesting as they are useful in polyurethane preparation via the use of relatively less toxic chemicals.23 We used 1,2,7,8-diepoxyoctane which exhibits similar reactivity to 1,2-epoxy-9-decene. This may be due to the presence of a relatively non-polar carbon chain in the diepoxide. Similarly, poly(ethylene glycol)diglycidyl ether (average Mn = 500) also showed relatively lower conversion (27%). We presume that this may be due to the presence of a long carbon chain attached to the epoxide moiety which is chemically inert compared to glycidyl ethers, and high viscosity of these three epoxides also affects their conversion. However, the conversions increased up to 74% and 47% after the reaction time was increased from 20 h to 68 h (Table 2, entries 10 & 11). Although neopentyl glycol diglycidyl ether contains two electronegative oxygen atoms, we believe that the observed lower conversion is likely due to its higher viscosity and the bulkiness of the quaternary carbon atom (Table 2, entry 12). However, 75% conversion was observed when 1,4-butanediol diglycidyl ether was used as the substrate. This is likely due to the similarity of the substrate to simple glycidyl ethers which showed excellent reactivity (Table 2, entry 13).
a Conditions: catalyst 100 mg or 1.58 mol% (based on the imidazolium cation); substrate, 15 mmol; a CO2 filled balloon (1.02 atm, 99.5% pure); time, 20 h; and temp., 105 °C. b The reaction time was 68 h. Conversion was measured using 1H NMR spectroscopy (Fig. S25 to S37, ESI).
To get more insight, the proposed mechanism for the cyclic carbonate conversion using this catalyst combination is shown in Fig. 2. First, the epoxide molecules are expected to approach the polymer likely due to the possibility of hydrogen bonding and ion–dipole interaction. This favours a facile counter anion attack on the epoxide which produces the halo-alkoxide anion. Subsequently, this anion attacks the CO2 molecule resulting in the catalytic incorporation of CO2 into the epoxide molecule. The final stage of the cycle involves the intramolecular ring closure resulting in the production of the cyclic carbonate molecules. In addition, we strongly presume that the incorporation of the triazine helps to absorb CO2 and separates the imidazolium centres which results in the excellent reactivity. Although, there is a chance that such reactivity may arise due to the homopolymer of 1,6-IL. To examine the fact, poly-1,6-IL was synthesized and used as a catalyst [see Fig. S1(b), ESI†]. Here, only 10% conversion was observed (Table 1, entry no. 14). This result indicates that the reactivity arises due to the thiol–ene polymeric catalyst. Moreover, another reason for the reactivity is the optimum separation of the active centres, i.e. imidazolium groups.
Fig. 2 Proposed mechanism for the 1,6-IL-TTCA/KI catalyzed epoxide to cyclic carbonate conversion.
To check the stability and heterogeneity of our catalyst recyclability experiments were performed in the presence and absence of the co-catalyst (see Fig. 3 and S38 in ESI†). A sharp decrease in the conversion was observed after the second cycle. Interestingly, further addition of 1.7 mol% KI resulted in complete conversion. This is because from the third cycle the catalysts reacted again synergistically resulting in complete conversion. A similar phenomenon occurred in the 5th cycle also. It is expected that with an increase in the number of catalytic cycles, the efficiency of the catalyst would decrease. We strongly believe that the retention of reactivity is obtained due to the anion exchange occurring during the reaction. To confirm our hypothesis, the polymer catalyst after 6 cycles was collected, washed with water for the complete removal of all the inorganic salts and subjected to EDAX analysis (please see the Experimental section, ESI†, for the washing protocol) The iodide incorporation in the polymer as a counter anion was found to be 0.62% which supports the anion exchange (see Table S2 and Fig. S39 in the ESI†). To further understand the stability of the catalyst, the material obtained after the 6th cycle was characterized again using TGA, SEM and PXRD analysis. The TGA profile reveals that the stability of the catalyst is preserved even after the 6th cycle (Fig. S40, ESI†). The SEM analysis showed that the catalyst retains its morphology after six cycles (Fig. S41, ESI†). From the PXRD analysis of the sample, it was noted that the catalyst was amorphous like the parent one but there is a slight 2° shift to a lower 2θ value. We presume that this is likely due to the increase in interlayer spacing. The observed decrease in intensity might be indicative of the destacking of the layers (Fig. S42, ESI†).
Fig. 3 Bar diagram showing the recyclability of the catalyst. Conditions: substrate, epichlorohydrin 15 mmol; in the third and fifth cycles 1.7 mol% KI was added; a CO2 filled balloon (1.02 atm, 99.5% pure); time, 20 h; and temp., 105 °C. Conversion was measured using 1H NMR spectroscopy.
In conclusion, we report for the first time the synthesis of a polymeric ionic liquid (IL) via thiol–ene click chemistry using trithiocyanuric acid, a dicationic IL. The resulting poly(ionic liquid) together with KI as a co-catalyst has been found to be very efficient for the conversion of epoxides into their corresponding cyclic carbonates under ambient CO2 pressure (i.e. under balloon conditions). The catalyst combination was very effective for the conversion of several epoxides to their corresponding cyclic carbonates. The recyclability study suggests that the heterogeneous catalyst was able to retain its activity up to 6 cycles. The developed catalyst utilized a cheap iodide source to improve the reactivity and provided good conversion for a wide range of substrates. Overall a bypass method was developed for the costly alkyl iodide reagent. We believe that further modification of the ionic liquid moiety or the use of different thiol precursors may provide a superior catalyst in future.
M. V. thanks the Department of Science and Technology (DST) for the project “EMR/2014/000204” and the Indian Institute of Science Education and Research (IISER) Kolkata for funding. T. B. thanks the UGC for a fellowship.
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Maddeningly, the Bush FDA continues overtly to spend time distracted from its mission – industry oversight and public safety – and instead, toil in support of the interests of the industries it is charged with regulating. Indeed, even as its end is near, the Bush FDA persists in waging its misguided war on drug and device litigation, attacking now with somewhat more precision that it has in the recent past. On August 22, 2008, in the form of a Final Rule published in the Federal Register, the FDA announced amendments to certain labeling regulations for prescription drugs, biologics, and medical devices. 73 Fed. Reg. 49603 (Aug. 22, 2008), available at http://www.gpoaccess.gov/fr/advanced.html.
With respect specifically to prescription drugs, the Final Rule amends 21 C.F.R. § 314.70 (Supplements and other changes to an approved application). The current version of Section 314.70, which remains in effect until September 22, 2008, is notable in several respects. First, it draws a distinction between those changes to a prescription drug that are permitted only with both prior notice to the FDA and prior FDA approval, see § 314.70(b), and those that are permitted with only prior notice to the FDA. See § 314.70(c). Changes to a drug’s labeling “[t]o add or strengthen a contraindication, warning, precaution, or adverse reaction” fall under the latter subsection. See § 314.70(c)(6)(iii)(A). Labeling changes of this nature have always been permitted without prior FDA approval. Second, subsection (c) is notable because it specifically makes discretionary the FDA’s response to a company’s supplemental submission under that subsection. Indeed, subsection (c)(7) states only that “if” the FDA disapproves of the supplement, it “may” order the company to cease distribution of the product with the accompanying change. See § 314.70(c)(7). In that way, the rule might be said to be doubly discretionary because it does not require the FDA to act on a subsection (c) supplement at all, and in the event that the FDA chooses to announce any disapproval of the change in question, it has discretion as to whether or not it will actually take action against the company.
In short, Section 314.70 highlights a straightforward and incontrovertible regulatory truth: the FDA itself has expressly authorized prescription drug manufacturers to unilaterally change drug label warnings, and when a company does so, the FDA is obligated to do absolutely nothing in response. Understandably, Section 314.70(c) has been a central feature of plaintiffs’ attorneys’ rebuttal to the conflict preemption argument in prescription drug cases. Obviously, in view of the plain text of Section 314.70, the prescription drug industry’s typical implied conflict preemption argument – i.e., that concurrent compliance with both FDA regulations and state tort suits sounding in failure to warn is “impossible” – rings rather hollow.
Against that backdrop, the upcoming amendment to Section 314.70 can hardly be considered coincidence. Whereas, the FDA’s prior efforts in the courts on behalf of the drug and device industries has come in the form of more ethereal means – e.g., amicus curiae briefing extolling the virtues of centralized decision-making and the now infamous “preemption preamble” to the FDA’s 2006 Rule Amendments – this latest effort is a more concrete affront to plaintiffs’ arguments. Indeed, the FDA’s addition of the “newly acquired information” and “causal association” requirements to Section 314.70 is an obvious effort to curtail plaintiffs’ reliance on the text of that regulation as direct support for (1) manufacturers’ ability to comply with both state failure to warn claims and federal labeling regulations, without conflict, and (2) the conception of federal labeling regulations as mere “minimum standards.” Of course, two features of the regulation will remain in tact – the ability of manufacturers to effectuate labeling changes without prior express approval from the FDA and the fact that any FDA response to such labeling changes is merely discretionary.
The good news for plaintiffs and consumers is that the changes cut against implied conflict preemption in all currently pending litigation and in all cases where the manufacturer’s alleged labeling deficiency occurred prior to the upcoming amendment effective date of September 22, 2008. Indeed, in adding two new requirements that must be met before a company unilaterally warns consumers and physicians about a given risk, the FDA is only acknowledging what plaintiffs have been arguing all along: current Section 314.70 is permissive rather than restrictive and cannot be perceived as the federal regulation “rock” to a state failure to warn claim’s “hard place.” In other words, once the new text takes effect and it becomes more difficult for companies to unilaterally warn under the federal regulations, it will correspondingly become more difficult for companies to claim that it was “impossible” to issue warnings under the current text.
Of course, the FDA attempts to nip that common sense argument in the bud by commenting repeatedly in its publication that the amendments merely “clarify” current “longstanding” procedures, that the agency does not believe that the amendments make it more difficult for manufacturers to strengthen labeling, and that the “rule is intended to describe FDA’s existing labeling standards and policies.” 73 Fed. Reg. at 49604. That rhetoric is no doubt meant to afford manufacturers an inroad to claim that Section 314.70 has always been restrictive. But the FDA and industry surely appreciate that such a position overreaches and amounts to little more than a thinly veiled, and likely unsuccessful, retroactivity argument.
It is probably most appropriate to understand the September 2008 amendments as the Bush FDA’s last-ditch effort to meaningfully advance its tort reform agenda for times to come – an attempt to lay groundwork for shielding companies from liability for future misdeeds. So the real question is: how will the amendments shape the conflict preemption debate for all interested parties going forward? The threshold answer is that, after the Supreme Court decides Wyeth v. Levine (see our prior blog entry about this upcoming Supreme Court case) the amendments might not matter. But assuming that Levine is decided in any way that makes the conflict preemption question turn on a factual inquiry, future arguments surely will center on what constitutes “newly acquired information” and whether a given company had evidence of a “causal association” between its drug and the risk in question.
But, in truth, the FDA’s Final Rule accomplishes very little for the drug industry in the way of future certainty as to the definitions of those terms. Most notably, the FDA defines “newly acquired information” rather broadly, explaining that it can be information arising from either “new clinical studies, reports, or adverse events, or new analyses of previously submitted data (e.g., meta-analyses).” 73 Fed. Reg. at 49604 (emphasis added). A manufacturer’s federal obligation to strengthen labeling based on the latter category would not appear necessarily to be at odds with common law negligence principles that would hold the manufacturer accountable for what it should have known. In other words, if a given drug risk could be gleaned from a fresh look at data in the company’s possession – even if that same data had already been turned over to the FDA – then the company could be found not only in violation of a common law negligence duty but also in dereliction of its obligation under the new Section 314.70(c)(6)(iii). Similarly, the addition of the “causal association” requirement merely parallels an element – proximate legal causation – that is required to prove a negligence claim under any state’s common law.
In our view, the September 2008 amendments serve mainly to underscore the present absence of any tangible conflict between federal labeling regulations and state failure to warn claims. And not to be lost in the fray of the agency’s transparent effort to secure preemption for the future is the reality that the text of the new labeling regulations will continue to belie any suggestion of an actual conflict between federal and state laws.


text:
Anashin V. V., Aulchenko V. M., Baldin E. M., Barladyan A. K., Barnyakov A. Yu, Barnyakov M. Yu, Baru S. E., Basok I. Yu, Beloborodova O. L., Blinov A. E., Blinov V. E., Bobrov A. V., Bobrovnikov V. S., Bogomyagkov A. V., Bondar A. E., Buzykaev A. R., Eidelman S. I., Grigoriev D. N., Glukhovchenko Yu M., Gulevich V. V., Gusev D. V., Karnaev S. E., Karpov G. V., Karpov S. V., Kharlamova T. A., Kiselev V. A., Kolmogorov V. V., Kononov S. A., Kotov K. Yu, Kravchenko E. A., Kulikov V. F., Kurkin G. Ya, Kuper E. A., Levichev E. B., Maksimov D. A., Malyshev V. M., Maslennikov A. L., Medvedko A. S., Meshkov O. I., Mishnev S. I., Morozov I. I., Muchnoi N. Yu, Neufeld V. V., Nikitin S. A., Nikolaev I. B., Okunev I. N., Onuchin A. P., Oreshkin S. B., Orlov I. O., Osipov A. A., Peleganchuk S. V., Pivovarov S. G., Piminov P. A., Petrov V. V., Poluektov A. O., Prisekin V. G., Ruban A. A., Sandyrev V. K., Savinov G. A., Shamov A. G., Shatilov D. N., Shwartz B. A., Simonov E. A., Sinyatkin S. V., Skrinsky A. N., Smaluk V. V., Sokolov A. V., Sukharev A. M., Starostina E. V., Talyshev A. A., Tayursky V. A., Telnov V. I., Tikhonov Yu A.
A high-precision determination of the main parameters of the ψ(2S) resonance has been performed with the KEDR detector at the VEPP-4M e +e - collider in three scans of the ψ(2S)-ψ(3770) energy range. Fitting the energy dependence of the multihadron cross section in the vicinity of the ψ(2S) we obtained the mass valueM=3686.114±0.007±0.011-0.012+0.002 MeV and the product of the electron partial width by the branching fraction into hadronsΓee×Bh=2.233±0.015±0.037±0.020 keV. The first and second uncertainties are statistical and systematic, respectively. The third uncertainty quoted is an estimate of the model dependence of the result due to assumptions on the interference effects in the cross section of the single-photon e +e - annihilation to hadrons explicitly considered in this work. Implicitly, the same assumptions were employed to obtain the charmonium leptonic width and the absolute branching fractions in many experiments.Using the result presented and the world average values of the electron and hadron branching fractions, one obtains the electron partial width and the total width of the ψ(2. S):. Γee=2.282±0.015±0.038±0.021 keV,Γ=296±2±8±3 keV.These results are consistent with and more than two times more precise than any of the previous experiments. © 2012.

matches: V. V. V. V. V. V. V. V. V. V. V. V. V. V. V. V.


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§ 7.1 - Colonial National Historical Park.
§ 7.2 - Crater Lake National Park.
§ 7.3 - Glacier National Park.
§ 7.4 - Grand Canyon National Park.
§ 7.5 - Mount Rainier National Park.
§ 7.6 - Muir Woods National Monument.
§ 7.7 - Rocky Mountain National Park.
§ 7.8 - Sequoia and Kings Canyon National Parks.
§ 7.9 - St. Croix National Scenic Rivers.
§ 7.10 - Zion National Park.
§ 7.11 - Saguaro National Park.
§ 7.12 - Gulf Islands National Seashore.
§ 7.13 - Yellowstone National Park.
§ 7.14 - Great Smoky Mountains National Park.
§ 7.15 - Shenandoah National Park.
§ 7.16 - Yosemite National Park.
§ 7.17 - Cuyahoga Valley National Park.
§ 7.18 - Hot Springs National Park.
§ 7.19 - Canyon de Chelly National Monument.
§ 7.20 - Fire Island National Seashore.
§ 7.21 - John D. Rockefeller, Jr. Memorial Parkway.
§ 7.22 - Grand Teton National Park.
§ 7.23 - Badlands National Park.
§ 7.24 - Upper Delaware Scenic and Recreational River.
§ 7.25 - Hawaii Volcanoes National Park.
§ 7.26 - Death Valley National Monument.
§ 7.27 - Dry Tortugas National Park.
§ 7.28 - Olympic National Park.
§ 7.29 - Gateway National Recreation Area.
§ 7.30 - Devils Tower National Monument.
§ 7.31 - Perry's Victory and International Peace Memorial.
§ 7.32 - Pictured Rocks National Lakeshore.
§ 7.33 - Voyageurs National Park.
§ 7.34 - Blue Ridge Parkway.
§ 7.35 - Buffalo National River.
§ 7.36 - Mammoth Cave National Park.
§ 7.37 - Jean Lafitte National Historical Park.
§ 7.38 - Isle Royale National Park.
§ 7.39 - Mesa Verde National Park.
§ 7.40 - Hopewell Village National Historic Site.
§ 7.41 - Big Bend National Park.
§ 7.42 - Pipestone National Monument.
§ 7.43 - Natchez Trace Parkway.
§ 7.44 - Canyonlands National Park.
§ 7.45 - Everglades National Park.
§ 7.46 - Virgin Islands Coral Reef National Monument.
§ 7.47 - Carlsbad Caverns National Park.
§ 7.48 - Lake Mead National Recreation Area.
§ 7.49 - Cape Lookout National Seashore.
§ 7.50 - Chickasaw Recreation Area.
§ 7.51 - Curecanti National Recreation Area.
§ 7.52 - Cedar Breaks National Monument.
§ 7.53 - Black Canyon of the Gunnison National Monument.
§ 7.54 - Theodore Roosevelt National Park.
§ 7.55 - Lake Roosevelt National Recreation Area.
§ 7.56 - Acadia National Park.
§ 7.57 - Lake Meredith National Recreation Area.
§ 7.58 - Cape Hatteras National Seashore.
§ 7.59 - Grand Portage National Monument.
§ 7.60 - Herbert Hoover National Historic Site.
§ 7.61 - Fort Caroline National Memorial.
§ 7.62 - Lake Chelan National Recreation Area.
§ 7.63 - Dinosaur National Monument.
§ 7.64 - Petersburg National Battlefield.
§ 7.65 - Assateague Island National Seashore.
§ 7.66 - North Cascades National Park.
§ 7.67 - Cape Cod National Seashore.
§ 7.68 - Russell Cave National Monument.
§ 7.69 - Ross Lake National Recreation Area.
§ 7.70 - Glen Canyon National Recreation Area.
§ 7.71 - Delaware Water Gap National Recreation Area.
§ 7.72 - Arkansas Post National Memorial.
§ 7.73 - Buck Island Reef National Monument.
§ 7.74 - Virgin Islands National Park.
§ 7.75 - Padre Island National Seashore.
§ 7.76 - Wright Brothers National Memorial.
§ 7.77 - Mount Rushmore National Memorial.
§ 7.78 - Harpers Ferry National Historical Park.
§ 7.79 - Amistad Recreation Area.
§ 7.80 - Sleeping Bear Dunes National Lakeshore.
§ 7.81 - Point Reyes National Seashore.
§ 7.82 - Apostle Islands National Lakeshore.
§ 7.83 - Ozark National Scenic Riverways.
§ 7.84 - Channel Islands National Park.
§ 7.85 - Big Thicket National Preserve.
§ 7.86 - Big Cypress National Preserve.
§ 7.87 - Kaloko-Honokohau National Historical Park.
§ 7.88 - Indiana Dunes National Lakeshore.
§ 7.89 - New River Gorge National River.
§ 7.90 - Chattahoochee River National Recreation Area.
§ 7.91 - Whiskeytown Unit, Whiskeytown-Shasta-Trinity National Recreation Area.
§ 7.92 - Bighorn Canyon National Recreation Area.
§ 7.93 - Guadalupe Mountains National Park.
§ 7.94 - Bryce Canyon National Park.
§ 7.95 - Pea Ridge National Military Park.
§ 7.96 - National Capital Region.
§ 7.97 - Golden Gate National Recreation Area.
§ 7.100 - Appalachian National Scenic Trail.

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no commercial benefit therefrom – as such PLN is a non-commercial use requester.
skills to turn the raw materials into a distinct work, and distributes that work to an audience.
subject to the record disclosure obligations under the FOIA, 5 U.S.C. § 552.
The BOP administers Federal Prison Industries, Inc., also known as UNICOR.
country with facilities in almost every state and approximately 219,000 inmates.
UNICOR. See Exhibit 1, FOIA request.
August 6, 2012. See id.
hazardous working conditions at UNICOR electronics recycling programs.
January 1, 2010 through July 31, 2012.
from January 1, 2010 through July 31, 2012.
from such exposure or conditions, from January 1, 2010 through July 31, 2012.
programs involving both inmates and employees.
duties/descriptions for such inmate workers.
contracts or subcontracts are related to UNICOR electronics recycling programs.
plaintiff or claimant, from January 1, 2010 through July 31, 2012.
pursuant to request no. 10.
which would involve the payment of public taxpayer funds. See Exs. 1, 4.
programs, both through its print publication and also via its website (www.prisonlegalnews.org).
government operations and activities at UNICOR.” See Ex. 1.
Prisoners Exposed to Toxic Dust at UNICOR Recycling Factories, 20 PLN 1 (Jan. 2009).
request. See Ex. 2, August 21, 2012, acknowledgement letter from the DOJ.
Federal Bureau of Prisons for processing. See id.
reviewing any responsive records. See Ex. 3, Denial Letter.
Prisons facilities[,]” and consist of no less than 14,000 pages. See id.
The BOP assessed $1,344.00 in search fees and $1,400 for duplication of records.
retrieval of these records.” See id.
format, despite assessing “duplication” fees. See id.
raw materials into a distinct work, and distributes that work to an audience. See 5 U.S.C.
by or free distribution to the general public.”).
“representative of the news media” status. See Ex. 3. As such, it was conceded.
The BOP is barred from assessing search fees on news media requesters. 5 U.S.C.
representative of the news media.”); 28 C.F.R. §§ 16.11(c), (d), 513.67.
U.S.C. § 552(a)(6)(A)(i); 28 C.F.R. §§ 16.6(c)(2), 513.66.
Nevertheless, the BOP assessed search fees for this request. See Ex. 3.
appealing to the head of the Agency. See Ex. 3.
The BOP failed to inform PLN of any deadline for filing an administrative appeal.
government and is not primarily in the commercial interest of the requester.” See id.
The public interest fee waiver denial was improper, bare and conclusory.
the head of the Agency.
failing to provide any deadline for appealing the denial.
outweighs the public interest in disclosure. See id.
request, the BOP denied the requested fee waiver.
operations or activities of the government. See id.
disclosure contribute to “public understanding”).
about this subject matter in any greater detail.” See id.
relevant timeframe of January 1, 2010 through July 31, 2012. See id.
to hazardous materials and working conditions during the timeframe covered by the request.
public’s ability to discover those particular cases.”).
country and on the internet, as opposed to having access to the information in a single document.
conditions that resulted in injuries or deaths among prisoners and employees. See Ex. 4 at 4.
programs operate with respect to hazardous or toxic materials or hazardous working conditions.
Agency, when such an appeal would be due, or where to file such an appeal. See Ex. 3.
C.F.R. §§ 16.6 (c)(4), 513.66.
requirement. See Oglesby v. Dept. of the Army, 920 F.2d 57, 65 (D.C. Cir. 1990).
and provided additional information in support of its request. See Ex. 4.
acknowledge the February 1, 2013, administrative appeal to date.
the BOP. See Ex. 5.
limits, thereby triggering the Act’s fee penalty provision. See id.; 5 U.S.C. § 552(a)(4)(A)(viii).
Finally, PLN requested “a prompt response, on or before April 10, 2013.” See Ex. 5.
communication regarding its processing of PLN’s administrative appeal.
records requests under the FOIA. 28 C.F.R. § 16.3(a).
10 days after the request was received by the DOJ Mail Referral Unit.
circumstances exist or have been asserted by the Agency.
media requester, if the agency has failed to comply with any time limit set forth under 5 U.S.C.
§ 552(a)(6). See 5 U.S.C. § 552(a)(4)(A)(viii).
make a determination of the administrative appeal within 20 business days.
request, given PLN’s representative of the news media status. See 5 U.S.C. § 552(a)(4)(A)(viii).
and withheld all responsive records.
released in electronic format where available.
provisions of this paragraph.” 5 U.S.C. § 552(a)(6)(C)(i) (emphasis added).
failed to respond to PLN’s status inquiry letter dated March 28, 2013.
business days. See 5 U.S.C. § 552(a)(6)(A)(ii).
PLN has exhausted all administrative remedies.
improper search fees and $1,400.00 in improper duplication fees.
under section 552(a)(4)(A) of the FOIA.
interest pursuant to section 552(a)(4)(A)(iii).
sections 552(a)(2) and (a)(3) of the Act.
penalty provision, 5 U.S.C. § 552(a)(4)(A)(viii).
and (C) of the FOIA, without requiring the formality of a written request.
responsive records by a date certain, without its having to pay search or duplication fees.
Grant such further relief as the Court may deem to be just and appropriate.


text:
Electron reflection at an interface is a fundamental quantum transport phenomenon. The most famous electron reflection is the electron→hole Andreev reflection (AR) at a metal/superconductor interface. While AR can be either specular or retro-type, electron→electron reflection is limited to only the specular type. Here we show that electrons can undergo retro-reflection in bilayer graphene (BLG). The underlying mechanism for this previously unknown process is the anisotropic constant energy band contour of BLG. The electron group velocity is fully reversed upon reflection, causing electrons to be retro-reflected. Utilizing a BLG/superconductor junction (BLG/S) as a model structure, we show that the unique low energy quasiparticle nature of BLG results in two striking features: (1) AR is completely absent, making BLG/S 100% electron reflective; (2) electrons are valley-selectively focused upon retro-reflection. Our results suggest that BLG/S is a valley-selective Veselago electron focusing mirror which can be useful in valleytronic applications.
Specular reflection of a particle by smooth solid wall is a classic textbook illustration on the principle of conservation of momentum1. Because the particle motion is intrinsically ‘locked’ to the direction of the momentum, the conservation of momentum parallel to the interface, ky, automatically implies the group velocity component parallel to the interface, vy, to remain unchanged upon reflection. This results in specular reflection (Fig. 1a). In the quantum mechanical case, retro reflection can occur at a superconducting interface via Andreev reflection (AR)2. AR is a two particle process in which an incident electron in the normal metal couples with another electron below the Fermi level to form a Cooper pair, crossing the interface into the superconductor3 and leaving behind a hole. Since the hole is a time reversed version of the incident electron, its vy is anti-parallel with ky. The conservation of ky requires a sign reversal of vy upon reflection. This results in electron→hole retro reflection. In graphene4 and a 2D semiconductor with Rashba spin-orbit coupling5, the pseudo-spin (graphene) and real-spin (Rashba semiconductor) nature of the two systems creates an additional ‘spin’-split branch: up-down Dirac cones in graphene and left-right sub-bands in the Rashba semiconductor. When forming an interface with a superconductor, the split branches form two ‘flavors’ of holes: one with ky parallel with vy and one with ky anti-parallel with vy. This allows both retro and specular AR to occur in these systems.
Figure 1: (a) Since electron group velocity component vy is locked to the momentum component ky, conservation of ky allows only specular electron reflection (SER) to occur; (b) retro electron reflection (RER) requires vy to be ‘unlocked’ from ky such that reversal of vy can still occur while conserving ky; (c) constant energy slice of a parabolic (or linear) energy spectrum.
The circular band contour allows only SER to occur; (d) constant energy slice of a hypothetical energy spectrum with boomerang-shaped band contour. The constant energy band contour of the incident states in k-space is convex while that of the reflected states is concave. The opposite band contours between incident and reflected states causes the sign reversal of vy upon reflection. This results in RER.
Retro reflection of electrons at an interface remains elusive. For retro electron reflection (RER) to occur, reversal of vy is required but this, however, violates the momentum conservation principle. To achieve RER, vy needs to be ‘unlocked’ from ky such that the direction of vy can be freely reversed upon reflection while conserving ky (Fig. 1b). We define a constant energy band contour as the outline of the energy spectrum across a constant energy slice in k-space. The concept of constant energy band contours will be useful in the qualitative understanding of the electron reflection trajectory, since it is directly related to the electron group velocity. Fig 1c shows the circular band contour of a parabolic (or linear) energy spectrum. In this case, specular electron reflection (SER) is the only permissible electron→electron reflection process since vy does not change sign upon reflection. We articulate that (i) anisotropic and (ii) opposite band contour for incident and reflected electron states are the fundamental criteria for an electron to be retro-reflected. Criterion (i) allows the electron motion to be unlocked from the direction of momentum since in an anisotropic band contour, the momentum no longer aligns with the group velocity while the direction of the group velocity is solely determined by the contour of the band via . Criterion (ii) allows the direction of vy to be reversed upon reflection. In Fig. 1d, a hypothetical energy spectrum with boomerang-shaped constant energy band contour in k-space is shown. The boomerang-shaped constant energy band contour is highly anisotropic in k-space. The constant energy band contour of the incident states is convex while that of the reflected states is concave. Along a constant line of ky, the reflected electron motion is completely reversed in both x- and y-direction. vy is reversed while conserving ky. The reflection process is hence RER.
The boomerang-shaped constant energy band contour occurs in a Bernal-stacked bilayer graphene (BLG). The low energy spectrum of BLG exhibits the trigonal warping effect (TW), i.e. the energy spectrum splits into four discrete low energy pockets which join to form a single-band at higher energy6. The TW has resulted in highly anisotropic constant energy band contour which fulfills both of the RER criteria. In the tight-binding framework, the low energy effective Hamiltonian is given as where ξ = 1(−1) for K (K′) valley, ε0 = (v3/vF)2γ1, k± = kx ± iky. The wave vectors are normalized by k0 and are dimensionless, i.e. kx ≡ kx/k0, ky ≡ ky/k0 where . The hopping parameters are γ1 = 0.3 eV, v3/vF = 0.1 and vF = 106 m/s6. The characteristic wave vector k0 defines the phase-space separation between central and satellite Dirac points. The low energy pockets join to form a single trigonally warped band structure at εk = ε0/4. The quadratic term in Eq. (1) represents the indirect electron hopping between B↑ and A↓ sublattices (↑ and ↓ denote upper and lower layer respectively) mediated by A↑-B↓ dimer pair while the linear term represents the weak direct electron hopping between the B↑ and A↓ side (Fig. 2a). The inclusion of the linear term anisotropically deforms the low energy dispersion: where φ is the momentum angle and ξ = ± is the valley-index. For simplicity, we denote εk ≡ εk,+ for the K-valley. The BLG energy spectrum exhibits three distinct categories of band contour (Fig. 2b): (A) the band structure splits into four distinct low energy ‘pockets’ at εk < ε0/4; (B) the pockets join to form a single band with ‘three-leaf’-like contour at ε0/4 < εk < 10.9ε0; and (C) the band contour becomes parabolic-like in the high energy regime of εk > 10.9ε0. Regime (B) is the most interesting since the reflection process is dominantly RER. The ‘three-leaf ’-shaped band contour is highly anisotropic. The incident electron states residing on the right-pointing ‘leaf ’ and the right-edges of the upper and lower leaves has a convex constant energy band contour while the reflected electron residing on the left-hand edge of the upper and lower leaves has a concave constant energy band contour. As shown in Fig. 2c, an incident electron with direction of motion pointing upwardly-right (red arrow) is reflected as an electron pointing downwardly-left (green arrow) along a constant line of ky. The reversal of vy while conserving ky results in RER. SER occurs only at large |ky| in which criteria (ii) no longer holds (incident and reflected electrons has the same constant energy band contour and hence vy does not change sign upon reflection). The very low energy regime (A) and high energy regime (C) are less ideal for RER. In Regime (A), RER occurs only minimally in the upper and lower pockets. In regime (C), the quadratic term in Eq. (1) dominates and the constant energy band contour loses the required boomerang-shaped constant energy band contour.
Figure 2: (a) Bernal-stacked bilayer graphene lattice structure; (b) the energy spectrum contour plot in phase space, showing three distinct energy regime: Regime (A): εk < ε0/4, Regime (B): ε0/4 < εk < 10.9ε0 and Regime (C): εk > 10.9ε0.
Retro electron reflection occurs optimally in Regime (B) due to its ‘boomerang-like’ anisotropic constant energy band contour in k-space. In high energy Regime (C), retro reflection is no longer possible as the band contour becomes parabolic-like; (c) Band contour of an constant energy slice in Regime (B). The green and blue arrows denotes incident and reflected electron direction of motion respectively. The opposite band contour between incident (convex) and reflected states (concave) causes vy to reverse its direction upon reflection, leading to RER.
In this work, we utilize a hybrid junction made up of a bilayer graphene and a superconductor (BLG/S) to theoretically demonstrate the unusual RER phenomena. The RER in BLG/S represents one last missing piece in the quantum transport phenomena of a superconducting interface where specular reflection of electrons, and retro and specular reflection of holes have all been demonstrated4,5,7,8,9,10,11. Not only RER occurs in such a junction, there are two additional surprises: (1) the 2π Berry phase of the BLG low energy electron forbids its transmission across the junction, resulting in the complete absence of AR; and (2) electron reflection in BLG/S is valley-dependent. The BLG/S acts as a valley-selective Veselago electron-mirror.
In the usual cases (parabolic or linear band structure), quasi-momentum angle φ = tan−1 (ky/kx) is commonly used to described particle trajectory. Each φ uniquely defines a particle traveling in the direction of φ. In BLG, φ is no longer locked to the electron motion due to the constant energy band contour anisotropy. Instead, the electron trajectory is more accurately described by group velocity angle θ = tan−1 (vy/vx). Unlike φ, the uniqueness of θ is lost. Each θ can simultaneously represent several electron states and hence becomes ambiguous. We therefore characterize the reflection problem by momentum component ky instead of the incident quasi-momentum angle θ or incident group velocity angle φ. The group velocity is given as where ν = x, y denotes x- and y-directional group velocity respectively. We consider the case where the reflection interface is placed along the y-direction. In Fig. 3a–c, vx of incident and reflected electrons across a constant energy slice are shown. vx has the opposite sign between incident electron and reflected electron and is highly asymmetric due to the broken left-right symmetry of the BLG band contour.
Figure 3: Group velocities of incident and reflected electrons.
(a)–(c) Group velocity vx; (d)–(f) group velocity vy; and (g)–(i) incident and reflection angles of an incident K valley electron at a given ky. The energies are εk = 0.5ε0, εk = 2ε0 and εk = 5ε0 respectively for column 1, 2 and 3. In (a)–(c), vx is positive for incident electrons and negative for reflected electrons. The RER regime is enclosed between the dashed lines in (d)–(i). In (d)–(f), sign reversal of vy corresponds to RER. In (g)–(i), the reflection angle of RER does not change sign since electron is reflected to the same side of the normal. At small εk, almost all of the permissible reflections are RER. As Ek increases, more permissible states becomes specular reflection states (which lies outside the RER windows) and the RER angle approaches 0°.
The group velocity component vy is the most important quantity in determining the electron reflection type (Fig. 3d–f). Sign reversal of vy at a fixed ky indicates RER (enclosed by dotted lines in the Fig. 3d–i). The incident electron vy reaches a sharp maximum when the band contour is flattened as ky increases. At , vy no longer changes sign upon reflection and the reflection becomes specular. At small εk, almost all permissible reflection states are within the RER window and hence RER is dominant. The specular reflection states (outside the RER window) expands as εk increases, making RER relatively less profound. At εk = 5ε0 (Fig. 3f), more than half of the permissible ky corresponds to specular reflection.
The non-uniqueness of θ is obvious in Fig. 3g–i, i.e. multiple sets of vx and vy produce the same θ. In contrast to vy, RER requires the sign of θ to remain unchanged upon reflection since in an retro reflection the electron is reflected to the same side of the normal of incidence. Due to the asymmetric constant energy band contour in k-space, the retro-reflected electrons do not trace back the incident path. Instead, they are mostly retro-reflected with smaller angle, maximally about 20°. The reflection angle approaches zero with increasing εk as the constant energy band contour becomes ‘smoother’ and loses the anisotropic band contour required to effectively produce large-angle RER. At εk > 10.9ε0, the reflection θ drops below zero, i.e. reflected electrons are placed on the opposite side of the incident normal, and therefore all electron reflection becomes specular-type.
A highly electron-reflective interface is preferred for the observation of RER. Such an interface conveniently occurs in a ballistic BLG/S junction (Fig. 4) where electron transmission across the junction is completely suppressed due to the spinor structure of the BLG electron wavefunction. The superconductor is assumed to be s-wave type with isotropic pairing potential Δ* = Δ and is induced intrinsically in BLG via the proximity effect12 (thus avoiding lattice mismatch problems). The quantum transport across the junction can be described by Bogoliubov-de Genne (BdG) equations in the form of HΨ(r) = εΨ(r), where H is the Hamiltonian describing the excitation in BLG/S junction. The reflection coefficients can then be obtained by solving the BdG equation and matching the wavefunctions at the boundary13 (see Supplementary Information). The reflection probabilities were found to be Rh = 0 and Re = 1 for AR and electron→electron reflection respectively. Electron→electron reflection is therefore the only permissible process in the low energy regime of BLG/S and such a junction acts as a 100% reflective electron-mirror.
Figure 4: RER in BLG/S junction.
Green, blue and gray arrows indicate incident electron, retro-reflected electron and transmitted quasiparticle respectively. Transmission across the junction is forbidden due to the 2π Berry phase nature of bilayer graphene electron. The junction is hence 100% electron-reflective.
The nature of RER in BLG/S is related to Veselago optics14. A Veselago electron-lens based on single layer graphene (SLG) and BLG p-n junctions has previously been reported15,16. Such junctions are Veselago electron-lenses because of the negative electron refractive index. In SLG, the negative electron refractive index originates from the existence of a lower Dirac sub-band which has opposite quasiparticle dynamics in comparison with the upper Dirac sub-band15. In BLG, the negative electron refractive index originates from its anisotropic constant energy band contour16. In contrast to a Veselago electron-lens, BLG/S is equivalent to a Veselago electron-mirror.
In optics, ray refraction is governed by Snell's Law where ni and nt are the refractive index at the incident side and at the transmitted side respectively. A negative sign is added to the right hand side of Eq. (2) since we define the reflection angle θr to have the same sign as the incident angle θi if the reflected ray is on the same side of the normal of incidence as the incident ray. For simplicity, we consider a Veselago lens with nt = −ni. Since θi = θr the transmitted ray is placed at the ‘wrong’ side of the normal of incidence and this results in the transmitted ray, originating from a point source, being re-focused after propagating a certain distance in the transmission side of the interface (Fig. 5a). The Veselago lens is therefore a flat lens with ray-focusing behavior. For the reflection problem, a reflection ‘Snell's Law’ can also be written as ni sin θi = −nr sin θr where nr is the refractive index on the reflected side. The reflection ‘Snell's Law’ is however redundant in the usual case, since reflection occurs in the same medium where nr = ni and hence θr = −θi. To construct a Veselago mirror, we consider a hypothetical anisotropic medium with nr = −ni, i.e. the refractive index of the medium undergoes a sign change when a ray travels in the opposite direction with respect to the incident ray. This leads to the retro-reflection condition of θr = θi. The reflection interface is Veselago-like since the reflected ray is placed at the ‘wrong’ side of the incident normal. The retro-reflected rays, emitted from a point source, trace back their original incident path and are re-focused at the incident side of the interface (Fig. 5b). The interface can therefore be regarded as a flat Veselago mirror with ray-focusing behavior. It becomes obvious that the RER effect in BLG/S is equivalent to a Veselago electron-mirror. In BLG/S, the absence of AR makes the interface a perfect electron-mirror and the RER process is Veselago-like. BLG/S is therefore a flat Veselago electron-mirror with electron focusing ability.
Figure 5: Schematic drawings of (a) Veselago lens with nt = −ni; and (b) Veselago mirror nr ≈ −ni.
In the Veselago lens, a ray emitted from a point source (denoted by yellow triangle) is focused at the transmitted side of the interface. For the Veselago mirror, nr ≈ −ni is chosen for better visual clarity. The retro-reflected ray is focused at the incident side of the interface.
In BLG, the low energy electrons reside in two inequivalent K and K′ valleys. Intervalley scattering is strongly suppressed17. Devices utilizing this robust valley degree of freedom in graphene, valleytronics, have been proposed18. The first step towards valleytronics is a valley polarizer. The RER phenomena of BLG/S junction offers another simple way to separate electrons from different valleys without the need of cutting18, straining19, terahertz laser-irradiating20 or selective-damaging21 graphene. The K and K′ electron excitation spectrum of BLG/S has an opposite constant energy band contour (Fig. 6a and Fig. 6b). The reflection states in the K valley have a much ‘smoother’ constant energy band contour (Fig. 6a) than the reflection states in the K′ valley (Fig. 6b). This immediately suggest that the electron reflection in BLG/S is valley-selective. In Fig. 6c, it can be seen that the K electrons are predominantly retro-reflected with small angle θ < 20° while the K′ electrons are predominantly retro-reflected with large angle 50° < θ < 70°. SER occurs only at the upper and lower tips of the constant energy band contour when |ky| is large. It should be emphasized that valley-selective reflection is only possible when electrons undergo retro-reflection. The specularly reflected electrons are always divergently reflected and the valley states are mixed since the upper and lower ‘tips’ of the constant energy band contour at large |ky| are approximately identical for both K and K′ valleys. In Fig. 6d, the RER trajectory of electrons injected from a point source is shown. The BLG/S junction acts as a valley-selective dual focusing electron mirror with K electrons being focused further away from the junction due to the ’smoother’ constant energy band contour of K reflection states while K′ electrons are focused closer to the junction due to the ‘sharper’ constant energy band contour of K′ reflection states.
Figure 6: The electron excitation spectrum of BLG/S at (a) a K valley and (b) a K′ valley with εF = 0.5ε0 and Ek = ε0.
The RER constant energy band contour of the K valley (red dashed curve) is significantly ‘smoother’ than that of the K′ valley (green dashed curve). At large |ky| (SER regime), K and K′ band contours become approximately identical; (c) Reflection angles of K (red curve) and K′(green curve) electrons. K electrons are predominantly focused via smaller angle (< 20°) than that of the K′ electrons (≈80°). (d) RER trajectory of electrons emitted from a point source situated at P (denoted by yellow triangle). Blue rays represent the incident electrons. The interface acts as a valley-selective dual-focus electron mirror with K electrons (red rays) being focused further away from the interface than the K′ electrons (green rays).
In Fig. 2, we show that the anisotropic constant energy band contour of BLG allows RER to occur. The reversal of vy group velocities upon reflection, as shown in Fig. 3, further illuminates the peculiar RER phenomena in BLG. It should be emphasized that the RER is more profound in the low energy regime of εk ≈ ε0. This requires high quality samples with carrier concentrations n ≈ 1011 cm−2 6 which is experimentally achievable22. RER does not survive in energy regimes higher than εk > 10.9ε0 since the reversal of vy upon reflection can no longer occur as the anisotropy of the constant energy band contour is lost.
The absence of AR in a BLG/S junction at low energy regimes is in agreement with previous study on BLG/S junction utilizing a four-band model without low energy band anisotropy23. It was shown that AR in BLG is a small effect in the order of Ek/γ1. Here we further demonstrate that AR is not only a small effect but is completely absent in the low energy regime. The absence of AR is related to the Klein tunneling effect and Berry phase in BLG. In BLG with isotropic and parabolic energy dispersion, electrons incident normal to a potential barrier are backscattered with unit-probability since the transmission mode normal to the interface is evanescent as encoded in the 2π Berry phase of its spinor wavefunction24,25. The 2π Berry phase is also retained when the low energy anisotropy is included26. Due to the large Fermi mismatch at the junction ( ), the transmission modes are always perpendicular to the interface for any incident angles and hence instead of perfect electron backscattering at only normal incidence, electrons reflect with unit probability at any incident angles in a BLG/S junction. Mathematically, this can be explained by the unique spinor-form of the BLG low energy electron wavefunctions. The transmitted spinor-wavefunction in the superconductor side for electron-like and hole-like excitations are, respectively, where u and v are the BCS coherence factors, , corresponds to the wavefunction amplitude at sub-lattice A ↑ and B ↓ respectively. The superscript (i, r) denotes incidence and reflection states respectively. Upon transmission, the normal-transmitted spinor follows the equality . This essentially uncouples the electron-reflection coefficient from the other transmission/hole-reflection coefficients, resulting in our angular-independent result: Re = 1 (see Supplementary Information). This aspect is in stark contrast to the single layer graphene/superconductor junction (SLG/S) where electrons reflect in an entirely opposite way: AR occurs with unit-probability only at normal incidence4. The perfect normal-transmission of electrons in graphene is a signature of the π Berry phase of the massless Dirac fermions24,27. The superconducting wavefunction in SLG/S is in the form of , where subscripts A and B correspond to the wavefunction amplitudes at the two inequivalent sub-lattices A and B respectively. Upon transmission, the spinor follows a rather different relation of . The hole and electron reflection coefficients are mathematically entangled with each others in this case and hence the AR reflection coefficient is angularly dependent on the electron incident angle.
In conclusion, graphene has again surprised us by allowing the peculiar RER to occur in its bi-layered form. The occurrence of RER in BLG while avoiding the violation of the momentum conservation rule represents a conceptually simple yet astonishing example highlighting one major difference between classical mechanics and quantum mechanics. In a BLG/S hybrid junction, the 2π Berry phase of low energy electrons in BLG manifests itself in a striking manner: AR is completely absent regardless the angle of incidence. This makes BLG/S a rather ideal platform to demonstrate RER since the competing AR process is fully eliminated. The absence of AR in BLG/S junction can be experimentally verified as the absence of supercurrent flow in the low Fermi level regime. Finally, the valley-inequivalent RER phenomena in BLG/S is analogous to a valley-selective Veselago electron-mirror. The valley-selective dual-focusing behavior suggests a potential application in the field of valleytronics.
See Supplementary Material for derivation of the reflection coefficients.
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We are thankful to Dr. David Martin (University of Wollongong) for fruitful discussion and his help in preparing this manuscript. The project is funded by Australian Research Council. ZSM acknowledges the financial support from the NBRP of China (2012CB921300), and NNSFC Grants (No. 91021017 and No. 11274013).
Y.S.A., Z.S.M. and C.Z. initiated the idea and performed the analysis. Y.S.A. performed simulation. All authors co-wrote and revised the manuscript.

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