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21.
In this paper, synthesis and characteristic of arylamine‐type molecules, particularly triphenylamine are discussed. An overview of the physical properties and chemical characteristics of these types of molecules is provided. Different synthesis methods and mechanisms involved for the production of these molecules and their analysis by HPLC are presented. Finally, a brief note about their purification is presented.  相似文献   
22.
Fourier transform near-infrared spectroscopy (FT-NIR) was evaluated to quantitatively determine 24 different measurands in honey. The reference values of 421 honey samples of different botanical origins were determined by classical physical and chemical methods. Partial least squares regression was used to develop the calibration models for the measurands studied. These calibrations were then validated using independent samples and proved satisfying accuracies for the determination of water (standard error of prediction: 0.3 g/100 g), glucose (1.3 g/100 g), fructose (1.6 g/100 g), sucrose (0.4 g/100 g), total monosaccharide content (2.6 g/100 g) as well as fructose/glucose ratio (0.09) and glucose/water ratio (0.12). The prediction accuracy for hydroxymethylfurfural, proline, pH-value, electrical conductivity, free acidity and the minor sugars maltose, turanose, nigerose, erlose, trehalose, isomaltose, kojibiose, melezitose, raffinose, gentiobiose, melibiose, maltotriose was poor and unreliable. The results demonstrate that near-infrared spectrometry is a valuable, rapid and non-destructive tool for the quantitative analysis of some measurands related to the main components in honey.  相似文献   
23.
Considering an infinite number of eigenvalues for time delay systems, it is difficult to determine their stability. We have developed a new approach for the stability test of time delay nonlinear hybrid systems. Construction of Lyapunov functions for hybrid systems is generally a difficult task, but once these functions are found, stability’s analysis of the system is straight-forward. In this paper both delay-independent and delay-dependent stability tests are proposed, based on the construction of appropriate Lyapunov-Krasovskii functionals. The methodology is based on the sum of squares decomposition of multivariate polynomials and the algorithmic construction is achieved through the use of semidefinite programming. The reduction techniques provide numerical solution of large-scale instances; otherwise they will be computationally infeasible to solve. The introduced method can be used for hybrid systems with linear or nonlinear vector fields. Finally simulation results show the correctness and validity of the designed method. Recommended by Editorial Board member Young Soo Suh under the direction of Editor Jae Weon Choi. The authors wish to express their thanks to Dr. A. Papachristodoulou and Dr. M. Peet for their helpful comments and suggestions. Mohammad Ali Badamchizadeh was born in Tabriz, Iran, in December 1975. He received the B.S. degree in Electrical Engineering from University of Tabriz in 1998 and the M.Sc. degree in Control Engineering from University of Tabriz in 2001. He received the Ph.D. degree in Control Engineering from University of Tabriz in 2007. He is now an Assistant Professor in the Faculty of Electrical and Computer Engineering at University of Tabriz. His research interests include Hybrid dynamical systems, Stability of systems, Time delay systems, Robot path planning. Sohrab Khanmohammadi received the B.S. degree in Industrial Engineering from Sharif University, Iran in 1977 and the M.Sc. degree in Automatic from University Paul Sabatie, France in 1980 and the Ph.D. degree in Automatic from National University, ENSAE, France in 1983. He is now a Professor of Electrical Engineering at University of Tabriz. His research interests are Fuzzy control, Artificial Intelligence applications in control and simulation on industrial systems and human behavior. Gasem Alizadeh was born in Tabriz, Iran in 1967. He received the B.S. degree in Electrical Engineering from Sharif University, Iran in 1990 and the M.Sc. degree from Khajeh Nasir Toosi University, Iran in 1993 and the Ph.D. degree in Electrical Engineering from Tarbiat Modarres University, Iran in 1998. From 1998, he is a Member of University of Tabriz in Iran. His research interests are robust and optimal control, guidance, navigation and adaptive control. Ali Aghagolzadeh was born in Babol, Iran. He received the B.S. degree in Electrical Engineering in 1985 from University of Tabriz, Tabriz, Iran, and the M.Sc. degree in Electrical Engineering in 1988 from the Illinois Institute of Technology, Chicago, IL. He also attended the School of Electrical Engineering at Purdue University in August 1998 where he was also employed as a part-time research assistant and received the Ph.D. degree in 1991. He is currently an Associate Professor of Electrical Engineering at University of Tabriz, Tabriz, Iran. His research interests include digital signal and image processing, image coding and communication, computer vision, and image analysis.  相似文献   
24.
A method is developed for the calculation of the saturation temperature of a KCI-NaCI aqueous solution, based on the measurement of the density and temperature of a sample solution, and prior knowledge of the NaCl concentration. Experimental density and solubility data for solutions saturated with KCI in the temperature range of 299 to 321 K with concentrations of NaCl greater than 0.200 kg/kg H2O were used to develop the empirical correlation allowing the calculation of the solution saturation level. The method is applicable in the on-line determination of the level of supersaturation in a KCI crystallizer in which the NaCl concentration is known. Knowledge of the prevailing supersaturation is necessary for the control of crystal purity and crystal size distribution in industrial potash crystallizers.  相似文献   
25.
A multiphase chemical equilibrium algorithm is developed which can be used with aqueous systems. The algorithm uses an average chemical potential for each species as a reference chemical potential. Incipient phases can be identified and their proximity to appearance can be determined through their tangent plane distance. Illustrative examples include the calculation of CaSO4 solubility and the calculation of vapour pressures above an SO2‐NaCl‐H2O system, including the prediction of a three‐phase equilibrium. The algorithm proved robust and versatile. The appearance of incipient phases was easily tracked. Future work needs to be done to optimize damping/acceleration coefficients in the calculations.  相似文献   
26.
Suggests a practical procedure for estimating the number of Ss that need to be screened to obtain a sample of fixed size that meets multiple correlated criteria. The procedure is based on the fact that least squares regression provides a good quadratic fit for Monte Carlo estimates of multivariate probabilities when they are plotted as a function of mean pairwise correlations (r) for the criterion variables. The equations given here can be used to predict selected 3- to 5-variable joint probabilities with reasonable accuracy as long as pairwise correlations for the selection criteria range from .10 to .90. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
A new brachytherapy (125)I source has been investigated at Iranian Agricultural, Medical and Industrial Research School. Dosimetric characteristics [dose-rate constant Λ, radial dose function g(l)(r) and anisotropy function F(r,)] of IRA-(125)I were theoretically determined in terms of the updated AAPM task group 43 (TG-43U1) recommendations. Versions 5 and 4C of the Monte Carlo radiation transport code were used to calculate the dosimetry parameters around the source. The Monte Carlo calculated dose-rate constant of the (125)I source in water was found to be 92×10(-4) Gy h(-1) U(-1) with an approximate uncertainty of ±3 %. Brachytherapy seed model, 6711-(125)I, carrying (125)I radionuclides, was modelled and benchmarked against previously published values. Finally, the calculated results were compared with the published results of those of other source manufacturers.  相似文献   
28.
Granulation of hydrophobic powders is frequently required in the pharmaceutical industry. The structural complexity of new drug molecules mean that is increasingly common for entire classes of drug compounds to be highly hydrophobic. This creates considerable difficulty in understanding, controlling and trouble-shooting these industrial granulation processes.There have been many recent advances in granulation theory. Essential to this theory is that wetting and spreading of the fluid through the powder particles is a prerequisite for good granulation. The possibility of a fine, hydrophobic powder spreading over the surface of the liquid during nucleation has been identified theoretically based on surface chemistry and as a potential nucleation mechanism. Recently, investigation confirmed that nucleation can occur by spreading of the sub-micron particles around the template drop to form a “liquid marble”. The hollow granule structure formed by the “solid-spreading” nucleation mechanism suggests the possibility of using the controlled, open granule structure to manufacture designer structured agglomerates with advantageous properties, including controlled granule structure and size and excellent ideal flow and handling properties. This paper describes single drop solid-spreading nucleation experiments where single fluid droplets are placed onto loosely packed powder beds of hydrophobic powders and the formation of the powder shell observed. Experimental results and observations for some model systems are presented, together with a preliminary framework for liquid marble formation.  相似文献   
29.
A state-of the-art survey of TOPSIS applications   总被引:1,自引:0,他引:1  
Multi-Criteria Decision Aid (MCDA) or Multi-Criteria Decision Making (MCDM) methods have received much attention from researchers and practitioners in evaluating, assessing and ranking alternatives across diverse industries. Among numerous MCDA/MCDM methods developed to solve real-world decision problems, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) continues to work satisfactorily across different application areas. In this paper, we conduct a state-of-the-art literature survey to taxonomize the research on TOPSIS applications and methodologies. The classification scheme for this review contains 266 scholarly papers from 103 journals since the year 2000, separated into nine application areas: (1) Supply Chain Management and Logistics, (2) Design, Engineering and Manufacturing Systems, (3) Business and Marketing Management, (4) Health, Safety and Environment Management, (5) Human Resources Management, (6) Energy Management, (7) Chemical Engineering, (8) Water Resources Management and (9) Other topics. Scholarly papers in the TOPSIS discipline are further interpreted based on (1) publication year, (2) publication journal, (3) authors’ nationality and (4) other methods combined or compared with TOPSIS. We end our review paper with recommendations for future research in TOPSIS decision-making that is both forward-looking and practically oriented. This paper provides useful insights into the TOPSIS method and suggests a framework for future attempts in this area for academic researchers and practitioners.  相似文献   
30.
The study of human behavior during driving is of primary importance for improving the driver??s security. In this study, we propose a hierarchical driver_vehicle_environment fuzzy system to analyze driver??s behavior under stress conditions on a road. We include climate, road and car conditions in fuzzy modeling. For obtaining fuzzy rules, experts?? opinions are benefited by means of questionnaires on effects of parameters such as climate, road and car conditions on driving capabilities. The number of fuzzy rules is optimized by Particle Swarm Optimization (PSO) algorithm. Also the frequency of pressing on brake and gas pedals and the number of car??s direction changes are used to determine the driver??s behavior under different conditions. Three different positions are considered for driving and decision making; one position in driving lane and two positions in opposite lane. A fuzzy model called Model 1 is presented for modeling the change of steering angle and speed control by considering time distances with existing cars in these three positions, the information about the speed and direction of car, and the steering angle of car. The behaviors of different drivers under two stress conditions are investigated. Also we obtained two other models based on fuzzy rules called Model 2 and Model 3 by using Sugeno fuzzy inference. Model 2 has two linguistic terms and Model 3 has four linguistic terms for estimating the time distances with other cars. The results of three models are compared. The comparative studies have shown that simulation results are in good agreement with the real world situations.  相似文献   
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