Rapid Determination of Volatile Constituents from the Buds and Flowers of Prunus Persica (L.) Batsch. f. duplex Rehd
The head-space (HS) volatile compounds of the buds and flowers of Prunus persica (L.) Batsch. f. duplex Rehd were analysed by solid-phase microextraction (SPME) coupled with capillary gas chromatography/mass spectrometry (GC-MS). Typical compounds detected in P. persica (L.) Batsch. f. duplex Rehd buds and flowers were alkanes. Tetradecane (4.07%), 4,8- dimethyl undecane (4.56%), pentadecane (11.3%) and hexadecane (4.62%) were identified as the main compounds in the buds, and tricosane (20.03%) , hexadecane (3.34%) were detected in the flowers as the main alkanes. On the other hand, (Z)-octadec-9-enoic acid (20.94%) was found in the buds as the main compounds.
Volatile constituents from flowers, leaves, bark and wood of Prunus mahaleb L.
Volatile constituents from air-dried flowers, leaves, stem-bark and wood of Prunus mahaleb L. (Rosaceae) were isolated by steam-distillation and analysed using GC and GC–MS; 130 components were identified. Aliphatic hydrocarbons, alcohols, carbonyls, fatty acids, terpenes, C13-norisoprenoids and phenylpropane derivatives were detected. Coumarin was identified as the main component of the bark volatiles (34.1%). Hexadecanoic acid was the main component in the wood (46.0%), and was also present in the leaves (17.8%) and bark (9.3%). n-Alkanes, heneicosane (22.1%) and octacosane (13.0%) were identified as the main components in the flowers, while eicosane was detected in the wood (12.9%). Phytol was identified in the leaves (5.1%). Dodecanoic, tetradecanoic and linoleic acids were present in all samples among the major components. The contents of volatile compounds were 340.0 mg/kg (flowers), 64.6 mg/kg (leaves), 41.0 mg/kg (bark) and 6.6 mg/kg (wood). Copyright © 2005 John Wiley & Sons, Ltd.
Using Fuzzy-Delphi technique to determine the concession period in BOT projects
BOT projects are affected by several risks and uncertainties. One of the most important issues in this type of contract is to determine the length of concession period considering these uncertainties. The previous studies have developed several models to determine the concession period. However, the uncertainties are not taking into account in most of the previous works. Moreover, none of the previous researches has the capability to aggregate the opinions of different experts being involved in a project regarding the values of the uncertain input parameters. In this research, a Fuzzy-Delphi technique is implemented to determine the length of concession period considering uncertainties. Using the proposed Fuzzy-Delphi technique, the values of different uncertain factors affecting a BOT project is determined considering opinions of a group of experts. The NPV value is calculated considering the resulted aggregated values of uncertain input parameters. Finally, the concession period is determined using fuzzy approach. A case study is conducted to evaluate the performance of the proposed methodology. It is shown that the concession period is determined more effectively using the proposed approach.