DC-2 GHz low loss cryogenic InAs/AlSb HEMT switch
A DC-2 GHz InAs/AlSb HEMT MMIC single pole double throw (SPDT) switch designed for cryogenic temperature has been fabricated and characterized. This switch is suitable for low RF power applications that require low insertion loss and high isolation. At 2 GHz, the SPDT switch demonstrated a typical low insertion loss of 0.7 dB at 300K and 0.3 dB at 90K. The isolation is greater than 40dB for both temperatures. These results demonstrate the outstanding potential of ABCS HEMT technology for low loss SPDT switches for cryogenic temperature.
Low-voltage high-speed antimonide-based compound semiconductor (ABCS) 2-μm InAs/AlSb HEMT MMIC process and its broadband switch application
In this paper, we present a low-voltage highspeed antimonide-based compound semiconductor (ABCS) high electron-mobility transistor (HEMT) monolithic microwave integrated circuit (MMIC) process and its single-pole double-throw (SPDT) broadband switch application. The measured 3-dB bandwidth of the proposed SPDT switch is from dc to 30 GHz. The switch features an insertion loss of less than 4 dB, and an isolation of greater than 18 dB between 10 MHz and 30 GHz. The measured input 1 dB compression point (P1dB) and third-order intercept point (IP3) at 100 MHz are 12.5 and 27 dBm, respectively. The chip size of the proposed switch is 0.75 × 0.58 mm2. These results demonstrate the outstanding potential of ABCS HEMT technology for low voltage switch applications.
Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform
This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN.