Separation of glycerolysis product using hexane
Mujdalipah, S.; Sasmita, A. H.; Amalia, I. K.; Suryani, A.
2016-04-01
Hexane is non-polar solvent and it can dissolve triglyceride and free fatty acid. The aim of this research is to get the hexane ratio to the glycerolysis product that can produce product that has the best characteristics. The study was conducted in five stages. In the first stage, the physicochemical properties of palm oil were analysed. In the second stage, palm oil glycerolysis was conducted. In the third stage, glycerolysis product was extracted by using hexane in various concentrations. In the following stage, physicochemical properties of extracted products were analysed. In the last stage, data were subjected to an analysis of variance. Results showed that ratio between glycerolysis product to hexane in this work did not significantly (α=0.05) affect the yield, the free glycerol content, and the ability of extracted products to reduce the surface tension of water. It was also found that the best treatment had yield of 28.5%. It was able to lower water surface tension from 72.00 to 31.80 dynes/cm and had free glycerol content of 2.40%. Base on this work, we found that further research need to be done.
Guo, Zheng
2008-01-01
be quantitatively associated with the structural characteristics of the IL by means of quantum chemical and COSMO-RS calculation. Misfit interaction, Van der Waals interaction and chemical potential, etc. derived from COSMO-RS calculation are shown to be effective measures to delineate multiple interactions of ILs...
Production of MAG via enzymatic glycerolysis
Jamlus, Norul Naziraa Ahmad; Derawi, Darfizzi; Salimon, Jumat
2015-09-01
Enzymatic glycerolysis of a medium chain methyl ester, methyl laurate was performed using lipase Candida antarctica (Novozyme 435) for 6 hours at 55°C. The percentage of components mixture of product were determined by using gas chromatography technique. The enzymatic reaction was successfully produced monolaurin (45.9 %), dilaurin (47.1 %) and trilaurin (7.0 %) respectively. Thin layer chromatography (TLC) plate also showed a good separation of component spots. Fourier transformation infra-red (FTIR) spectrum showed the presence of ester carbonyl at wavenumber 1739.99 cm-1 and hydrogen bonded O-H at 3512.03 cm-1. The product is potentially to be used as emulsifier and additive in food industry, pharmaceutical, as well as antibacterial.
Tri-Panji*
2014-06-01
Full Text Available Diacylglycerol (DAG produced from crude palm oil (CPO is one of the healthy oils that can be consumed for daily human diet. DAG production in Indonesia is constrained by the high cost of the mostly imported lipase. To overcome this problem, research of DAG production has been carried out using crude extracts of lipase produced by local species of fungi Rhizopus oryzae. This study aims to develop a continuous process of enzymatic glycerolysis of CPO for DAG production; to establish optimum conditions of DAG production which includes flow rate of CPO and glycerolysis time; and to test the performance of lipase from the local mold R. oryzae in catalyzing continuous process of glycerolysis for the production of DAG. Lipase isolation was carried out by acetone precipitation and lipase was used as a catalyst in the continuous glycerolysis process. The glycerolysis was conducted by reacting CPO with glycerol continuously at various time periods. The optimum condition of automatic continuous glycerolysis process was achieved at a CPO flow rate of 3 mL/min with a glycerolysis time at the 18 cycles (9 hours. The conversion of DAG was 29%. The performance of lipase was proven to remain stable up to 3 times changes of CPO substrate for 9 hours of glycerolysis process with the best condition at the 3 cycles and can improved conversion of DAG until 37%.
Diacylglycerol synthesis by enzymatic glycerolysis: Screening of commercially available lipases
Kristensen, Janni Brogaard; Xu, X.B.; Mu, Huiling
2005-01-01
yield (approx. 60 wt%) was achieved with Novozym 435 and Lipase PS-D after 7 h, and an equilibrium was obtained. Stepwise addition of glycerol allowed catalysis with Novozym CALB L (immobilized) to take place in spite of the hydrophilic carrier; however, the DAG yield was only 19 wt%. This result...... suggests that glycerol forms a layer around the hydrophilic lipase particles, limiting contact between the lipases and the hydrophobic oil phase. With glycerol absorbed on silica gel, all lipases catalyzed the glycerolysis reaction. Faster conversion of TAG was obtained with Lipase PS-D, Lipase AK...
Yang, Tiankui; Rebsdorf, Morten; Engelrud, Ulrik
2005-01-01
The aim of the study was to develop an efficient glycerolysis system for the enzymatic production of monoacylglycerols (MAGs) containing polyunsaturated fatty acids. Glycerolysis has been widely applied in industry for the chemical production of food MAGs under high temperature. The enzymatic...... glycerolysis system at 40-70 °C is unfortunately a multiphase system, which leads to the lower reaction efficiency. A tert-butyl alcohol system was developed after careful evaluation and more than 20-fold of the reaction efficiency from this system was obtained compared to the solvent-free system. Novozym 435...... was employed as a catalyst in the glycerolysis from the screening. In the batch reaction system with tert-butyl alcohol, temperature higher than 40 °C was favored. The glycerol/oil ratio was best in the study with 4.5 while the solvent weight ratio from 1 to 3 had little effect. In general, 60- 70% yield can...
Monoglycerides and Diglycerides Synthesis in a Solvent-Free System by Lipase-Catalyzed Glycerolysis
Fregolente, Patricia Bogalhos Lucente; Fregolente, Leonardo Vasconcelos; Pinto, Gláucia Maria F.; Batistella, Benedito César; Wolf-Maciel, Maria Regina; Filho, Rubens Maciel
Five lipases were screened (Thermomyces lanuginosus free and immobilized forms, Candida antarctica B, Candida rugosa, Aspergillus niger, and Rhizomucor miehei) to study their ability to produce monoglycerides (MG) and diglycerides (DG) through enzymatic glycerolysis of soybean oil. Lipase from C. antarctica was further studied to verify the enzyme load (wt% of oil mass), the molar ratio glycerol/oil, and the water content (wt% of glycerol) on the glycerolysis reaction. The best DG and MG productions were in the range 45-48% and 28-30% (w/w, based on the total oil), respectively. Using immobilized lipases, the amount of free fatty acids (FFA) produced was about 5%. However, the amount of FFA produced when using free lipases, with 3.5% extra water in the system, is equivalent to the MG yield, about 23%. The extra water content provides a competition between hydrolysis and glycerolysis reactions, increasing the FFA production.
Lipase - Catalyzed glycerolysis of sunflower oil to produce partial glycerides.
Zaher, F. A.
1998-12-01
Full Text Available Partial glycerides were prepared by glycerolysis of sunflower oil in presence of lipase enzyme as catalyst. Six lipases of different origins were used and compared for their catalytic activity. These include Chromobacterium lipase, pancreatic lipase, Rhizopus arrhizus lipase, lyophilized lipase (plant lipase in addition to two lipase preparations derived from Rhizopus japonicas; Lilipase A-10 and Lilipase B-2. Chromobacterium lipase was found to be the most active as glycerolysis catalyst whereas lyophilized lipase; a plant preparation from wheat germ was the least active. The results have also shown that the lipase type affects also the product polarity and hence its field of application as a food emulsifier. Less polar products can be obtained using Chromobacterium lipase whereas the more polar ones using a fungal lipase preparation «Lipase A-10». The product polarity is also influenced by the process temperature but the mode of its effect is different for different lipases.
Se prepararon glicéridos parciales mediante glicerolisis de aceite de girasol en presencia de lipasa como catalizador. Seis lipasas de orígenes diferentes se utilizaron y compararon en función de su actividad catalítica. Estas incluyeron lipasa de Chromobacterium, lipasa pancreática, lipasa de Rhizopus arrhizus, lipasa liofilizada (lipasa vegetal además de dos preparaciones de lipasa derivadas de Rhizopus japonicus: lilipase A-10 y lilipase B-2. Se encontró que la lipasa de Chromobacterium fue la más activa como catalizador en la glicerolisis mientras que la lipasa liofilizada, preparación vegetal a partir de germen de trigo, fue la menos activa. Los resultados mostraron que los tipos de lipasa afectan también a la polaridad de los productos y por tanto a los rendimientos en su aplicación como emulsificantes alimentarios. Los productos menos polares pueden obtenerse usando lipasa de
Monoacylglycerol synthesis via enzymatic glycerolysis using a simple and efficient reaction system
Yang, Tiankui; MORTEN, REBSDORF; ULRIK, ENGELRUD
2005-01-01
TL IM and Novozym 435 were employed in a batch reaction system. Novozym 435 showed better properties in glycerolysis. The increased temperature and high glycerol/oil ratio had little effect on the yield of MAGs in such a system. The reaction in a packed bed reactor (PBR) gave lower yield of MAGs...... because of the insufficient contact between the oil and the glycerol in the continuous reactor. The low homogeneity in the enzymatic glycerolysis system was the obstacle to improve the MAG yield, thus, tert-butanol was used in the reaction system. The equilibrium yield of up to 70% MAGs in the selected...
Lipase-catalyzed glycerolysis of fish oil to obtain diacylglycerols
Baeza-Jiménez, R.
2013-06-01
Full Text Available Diacylglycerols (DAG rich in n-3 residues were successfully produced by Novozym 435-catalysed glycerolysis of n-3 PUFA rich fish oil. Orbital and magnetic agitations were evaluated in order to minimize mass transfer limitations and thus assure the homogeneity of the reactant mixture. Different temperatures (65, 70, 75, 80, 85 and 90 °C and speeds (300, 500, 700 and 900 rpm were tested. Optimal conditions to obtain the highest amount of DAG were: 65 °C, with a substrate molar ratio of 3:1 (oil:glycerol, 500 rpm and 15% enzyme load after 2.5 h, with a yield of 60%.Diacilglicéridos (DAG ricos en n-3 fueron producidos en la glicerolisis de aceite de pescado rico en n-3 PUFA catalizada por Novozym 435. Las agitaciones orbital y magnética fueron evaluadas con el propósito de minimizar las limitaciones de transferencia de masa y garantizar la homogeneidad de la mezcla de reactivos. Diferentes temperaturas (65, 70, 75, 80, 85 y 90 °C y velocidades de agitación (300, 500, 700 y 900 rpm fueron empleadas. Las condiciones óptimas para alcanzar la mayor cantidad de DAG fueron: 65 °C, una relación molar de sustratos 3:1 (aceite:glicerol, 500 rpm y 15% de enzima, después de 2.5 h, con un rendimiento de 60%.
Damstrup, Marianne; Kiil, Søren; Jensen, Anker Degn
2007-01-01
Continuous and easily operated glycerolysis was studied in different lipase-packed columns to evaluate the most potential process set-ups for industrial monoacylglycerol (MAG) production. Practical design-related issues such as enzyme-filling degree, required reaction time, mass transfer investig...
Damstrup, Marianne; Jensen, Tine; Sparsø, Flemming V.;
2005-01-01
This study was aimed at screening solvent systems of varying polarities to identify suitable solvents for efficient and practical enzymatic glycerolysis. Several pure solvents and solvent mixtures were screened in a batch reaction system consisting of glycerol, sunflower oil, and Novozymo (R) 435...
The utilization natural mineral in the process of palm oil glycerolysis
Mujdalipah, Siti
2015-09-01
The reaction of glycerolysis currently has weakness, which uses a catalyst with a high price and performed at a high temperature. Indonesia is rich in minerals that have the potential to be used as a catalyst. Besides that, the solvent allows the glycerolysis reaction done in a low temperature so that it can maintain the quality of product. The purpose of this research is to study the influence of a type of solvent and a type of natural mineral to the chemistry and physical characteristic of palm oil glycerolysis product. The research activity consists of four steps. The first is the analysis of chemistry characteristics of palm oil. The second is the process of palm oil as the effect of a type of solvent and a type of natural mineral factors. The third is the analysis of chemistry and physical characteristics of glycerolysis product. The last is the analysis of data. Based on the analysis variant at α=0.05, it shows that type of solvent and type of natural mineral doesnot influence significantly to the ability of glycerolysis product in decreasing the water surface tension and to the free glycerol content. The best product is able to decrease the water surface tension from 44.933 dyne/cm to 29.00 dyne/cm. It contains the free glycerol content of 1.30%, 1-monoglyceride content of 43.10%, acid number of 0.146 mg KOH/g sample, and it has simillar fatty acid composition with the raw material.
. In spite of optimal reaction conditions a complex heterogeneous reactant mixture with a glycerol in oil emulsion occurs. Hence, the movement of material from phase to phase as well as through the catalyst pores becomes important since it can influence the performance of the immobilized enzyme reactor....... To examine which basic features that need to be considered to obtain an industrially beneficial procedure continuous and easily operated glycerolysis was studied in different lipase packed columns. Immobilized Candida antarctica lipase B was used to catalyze the glycerolysis reaction between glycerol...... and sunflower oil dissolved in a binary tert-butanol:tert-pentanol medium. Practical design-related issues such as required reaction time, enzyme capacity, expansion of the enzyme during wetting, and the effect of different column length-to-diameter ratios, fluid velocities and particle sizes of the enzymes...
Damstrup, Marianne L.; Jensen, Tine; Sparsø, Flemming V.;
2006-01-01
The aim of this study was to optimize production of MAG by lipase-catalyzed glycerolysis in a tert-pentanol system. Twenty-nine batch reactions consisting of glycerol, sunflower oil, tert-pentanol, and commercially available lipase (Novozym®435) were carried out, with four process parameters bein...
Lignin recovery from alkaline hydrolysis and glycerolysis of oil palm fiber
Hassan, Nur Syakilla; Badri, Khairiah Haji
2014-09-01
In the present work, two types of treatment namely alkaline hydrolysis and glycerolysis have been conducted for lignin extraction from oil palm empty fruit bunch (EFB) fiber. Lignin has been retrieved from two sequential methods, which was the klason lignin from residue and lignin from precipitation of the filtrate. Alkaline hydrolysis was performed using 10% NaOH solution at room condition. This has extracted 13.0 % lignin. On the other hand, glycerolysis was carried out using 70% glycerol catalyzed with 5% of 1 M NaOH at 60-70 °C. This has successfully extracted 16.0% lignin. The SEM micrographs exhibited some physical changes on the surface where the impurities and waxes have been removed, exposing the, lumen. Besides that, FTIR analysis was conducted on untreated EFB, treated EFB and extracted lignin. Delignification of EFB fiber was confirmed based on the intensity reduction at 1245 cm-1 that showed lignin was removed from the fiber. The presence of CO, CC and CC aromatic peaks in the FTIR spectra of the dried filtrate gave an evidence on the presence of lignin.
Guo, Zheng; Xu, Xuebing
2006-01-01
Candida antarctica lipase B-catalyzed glycerolysis of sunflower oil in a tetraammonium-based ionic liquid (IL) was studied to elucidate its distinct characteristics and to evaluate the contributions of important parameters. Mass transfer limitations and occurring partial phase separation were found...... and enzyme loading study. Interestingly, increasing water activity resulted in a decreasing initial reaction rate and a prolonged induction period, which possibly resulted from an elevated solvation barrier and the phase separation at higher water content. Studies on thermodynamics of glycerolysis show...... that there is a bigger energy barrier for the IL system, about 1.5 times that of the solvent-free or 3 times that of the tert-butyl alcohol system. Kinetic studies also show that IL system has the biggest Vmax and Km among the three tested systems, indicating, respectively, its high productivity, and low substrate...
Guo, Zheng; Xu, Xuebing
2006-01-01
and enzyme loading study. Interestingly, increasing water activity resulted in a decreasing initial reaction rate and a prolonged induction period, which possibly resulted from an elevated solvation barrier and the phase separation at higher water content. Studies on thermodynamics of glycerolysis show...... to have a profound effect on the lower initial rate and the occurrence of the induction period. The investigation on the rheological behavior of the IL and its mixture with substrates showed that the plot of the viscosity of pure IL against temperature was better fitted with the Vogel–Tammann–Fulcher (VTF......) equation, and the viscosity of the mixture is strongly agitation-dependent. A comparable diffusion time constant of the oil molecule in the IL to that of the reaction shows that the glycerolysis in the IL is controlled both diffusionally and kinetically, as experimentally verified by agitation effect...
Theoretical and experimental characterization of the first hyperpolarizability
Perez-Moreno, Javier
We present a theoretical and experimental study of the molecular susceptibilities. The generalized Thomas-Kuhn sum rules are used to characterize the nonlinear response of organic chromophores in terms of fundamental parameters. The nonlinear optical performance of real molecules is evaluated from the calculation of the quantum limits and Hyper-Rayleigh scattering measurements. Different strategies for the enhancement of nonlinear behavior at the molecular and supramolecular level are evaluated and new paradigms for de design of more efficient nonlinear molecules are proposed.
Singh Kumar Abhishek
2014-01-01
Full Text Available In the present work, solvent free olive oil glycerolysis for the monoglycerides (MG and diglycerides (DG production with an immobilized Candida rugosa lipase was studied. MG and DG production were optimized using experiment design techniques and response surface methodology (RSM. RSM based on five-level, a five-variable central composite design (CCD was used to optimize MG and DG production: reaction time, temperature, molar ratio of glycerol to oil, amount of lipase, and water content in glycerol. The reaction time, temperature, and amount of lipase were observed to be the most significant factors on the process response. The immobilized Candida rugosa lipase revealed optimum yield of MG and DG as 38.71 and 40.45 wt% respectively following a 5h reaction time with 0.025 g of lipase and 5% water content in glycerol at 40°C temperature. The yield of MG and DG production can be enhanced 1.5 fold by RSM.
尹春华; 刘涛; 谭天伟
2005-01-01
Glycerolysis of Chinese vegetable tallow (CVT) fraction was investigated using a 1,3-specific lipase from Rhizopus arrhizus as catalyst. Based upon a binary gradient HPLC with an evaporative light-scattering detector (ELSD), the contents of free fatty acids (FFA), monoglycerides (MG), diglycerides(DG) and triglycerides (TG)with their positional isomers during the glycerolysis were determined. The effects of water content and the ratio of glycerol to oil on the product distribution of glycerolysis were studied. Under the optimum reactant conditions:250 units lipase per gram oil at 37 ℃ with 1:2 molar ratio of oil to glycerol in a solvent-free system, after 24 h reaction, the product consisted of 7.2% TG, 25.6% MG, 56.1% DG and 4.9% FFA (all by mass). Furthermore, the mechanism of glycerolysis was discussed in detail.
Cai, Chunsheng; Gao, Yongqing; Liu, Yan; Zhong, Nanjing; Liu, Ning
2016-12-01
In this study, Candida antarctica lipase B (CALB) was immobilized on SBA-15 with three pore diameters. CALB loading was found increased with CALB concentration increasing from 20.3 to 80.12μg/ml. Higher CALB loading was observed from SBA-15 with pore diameters at 8.1nm (SBA-15(8.1)), yet highest hydrolytic activity was found at SBA-15(12.5). Thermal stability of the immobilized CALB (SBA-15-CALB) samples was greatly influenced by their water content, after 4h storage at 70°C, 8.93 and 67.4% of the initial activity was observed from SBA-15-CALB samples with water content at 9.23 and 3.22% respectively. The SBA-15-CALB samples were then used in glycerolysis of corn oil, and 53.6wt% of diacylglycerols was obtained after optimization. The operational stability was tested, and after 5 consecutive applications, 92.5 and 80.3% of the initial glycerolysis activity was remained respectively from SBA-15(6.6)-CALB and SBA-15(12.5)-CALB.
Olive oil glycerolysis with an immobilized lipase Candida antarctica in a solvent free system
Mukhopadhyay, M.
2012-06-01
Full Text Available In the present work, the solvent free lipase glycerolysis of olive oil for the production of monoglyceride (MG and diglyceride (DG with an immobilized Lipase B Candida antarctica was studied. The experiments were performed in batch mode by varying different process parameters. The Results showed that the MG and DG yields were dependent on operating conditions such as time, temperature, glycerol/ oil molar ratio, enzyme concentration and the water content in glycerol. The optimum operating time for maximum MG, 26 wt% and DG, 30 wt% production was 3h. The initial reaction rate was studied by varying different process parameters for 1h. The initial reaction rate increased at 30 °C temperature, 2:1 glycerol/oil molar ratio, 3.5% (w/w water content in glycerol and 0.015g of enzyme loading. Comparative data for MG and DG yields for different oils and enzyme combinations were presented.En el presente trabajo se ha estudiado la glicerolisis sin disolvente de aceites de oliva para la producción de monoglicéridos (MG y diglicéridos (DG, con la lipasa inmovilizada Candida antarctica. Los experimentos fueron realizados por lotes, variando distintos parámetros del proceso. Los resultados mostraron que los rendimientos de MG y DG dependen de las condiciones de operación como el tiempo, la temperatura, la relación molar glycerol/aceite, la concentración de la enzima y del contenido en agua del glicerol. El tiempo óptimo de la operación fue de 3h para un rendimiento máximo en peso del 26% de MG, y del 30% de la producción en peso de DG. La velocidad de reacción inicial ha sido estudiada variando los diferentes parámetros del proceso durante 1h. La velocidad de reacción aumenta a la temperatura de 30 °C, con una relación molar 2:1 glicerina/aceite, un contenido de agua en glicerol de 3,5% (w/w y una carga de enzima de 0.015g. Se presentan datos comparativos de redimientos de MG y DG para diferentes aceites y combinaciones de enzima.
Characterizing quantum theory in terms of information-theoretic constraints
Clifton, R; Halvorson, H; Clifton, Rob; Bub, Jeffrey; Halvorson, Hans
2003-01-01
We show that three fundamental information-theoretic constraints--the impossibility of superluminal information transfer between two physical systems by performing measurements on one of them, the impossibility of broadcasting the information contained in an unknown physical state, and the impossibility of unconditionally secure bit commitment--suffice to entail that the observables and state space of a physical theory are quantum-mechanical. We demonstrate the converse derivation in part, and consider the implications of alternative answers to a remaining open question about nonlocality and bit commitment.
Information-theoretic characterization of uncertainty in manual control
Trendafilovv, D.; Murray-Smith, R.
2013-01-01
We present a novel approach for quantifying the\\ud impact of uncertainty in manual control, based on information\\ud and control theories and utilizing the information-theoretic\\ud capacity of empowerment, a task-independent universal utility\\ud measure. Empowerment measures, for agent-environment systems\\ud with stochastic transitions, how much influence, which can be\\ud sensed by the agent sensors, an agent has on its environment.\\ud It enables combining different types of disturbances, aris...
Theoretical characterization of formamide on the inner surface of montmorillonite
Shi, Jing; Lou, Zhaoyang; Yang, Mingli; Zhang, Yao; Liu, Houbin; Meng, Yingfeng
2014-06-01
Density functional theory calculations were performed to characterize the low-lying structures of formamide (FA) and protonated formamide (FAH) in the interlayer space of montmorillonite (MMT). The interactions among FA/FAH, H2O, Na+, and the inner surface of MMT were systematically analyzed. The carbonyl-O of FA/FAH has strong coulomb interaction with Na+, while its amide-H forms hydrogen bonds (HBs) with water and MMT surface. The adsorption of FA is promoted by H2O, which exhibits a cooperative adsorption effect by enhancing the FA-Na+ coulomb interaction and by forming HBs with FA. Our study reveals the structural basis of FA/FAH as an intercalator for MMT splitting.
Theoretical characterization of McReynolds' constants
Rajko, Robert [Department of Unit Operations and Environmental Engineering, College Faculty of Food Engineering, University of Szeged, H-6701 Szeged, P.O. Box 433 (Hungary)]. E-mail: rajko@sol.cc.u-szeged.hu; Koertvelyesi, Tamas [Department of Physical Chemistry, University of Szeged, H-6701 Szeged, P.O. Box 105 (Hungary)]. E-mail: kortve@chem.u-szeged.hu; Sebok-Nagy, Krisztina [Chemical Research Center, Hungarian Academy of Sciences, H-1525 Budapest, P.O. Box 17 (Hungary); Goergenyi, Miklos [Department of Physical Chemistry, University of Szeged, H-6701 Szeged, P.O. Box 105 (Hungary)
2005-12-04
The properties of McReynolds' constants were studied by a detailed statistical/chemometric analysis. The electronic structure, geometries and hydrophobicity of the McReynolds' test compounds (benzene, 1-butanol, 2-pentanone, 1-nitropropane, pyridine, 2-methyl-2-pentanol, 1-iodobutane, 2-octyne, 1,4-dioxane and cis-hidrindane) were calculated at the level of PM3 semiempirical quantum chemical method and empirical formulas. The predominant pattern was revealed using cluster and principal component analyses (CA and PCA). Dependence of McReynolds' constants on the calculated chemical descriptors was modeled by multiple linear regression (MLR) with stepwise selections, principal component regression (PCR) and partial least-square regression (PLSR). A novel statistical approach was developed for case-and-variable selection using the PCR and PLSR methods for characterizing and modeling the polarity of 25 gas chromatography (GC) stationary phases (phthalates, adipates, sebacates, phosphates, citrates and nitrils). Highest occupied molecular orbital energy, dipole moment, averaged isotropic polarizability and the apolar solvent accessible surface area; and energy of the lowest unoccupied molecular orbital and total solvent accessible surface area were suitable to describe the McReynolds' constants based on the results obtained using Q {sup 2} and adjusted-Q {sup 2}. Six of the 10 test compounds were found to be sufficient for the description of the polarity of the columns studied.
Solaesa, Ángela García; Sanz, María Teresa; Falkeborg, Mia; Beltrán, Sagrario; Guo, Zheng
2016-01-01
Production of monoacylglycerols (MAGs) rich in ω-3 polyunsaturated fatty acids (n-3 PUFAs) was conducted through short path distillation (SPD) of an acylglycerol mixture (containing 67% MAGs) produced by enzymatic glycerolysis of sardine oil with glycerol. A stepwise SPD process in a UIC KDL 5 system (vacuum 10(-3)mbar, feeding flow 1.0 mL/min) was proceeded: the first distillation performed at evaporator temperature (TE) of 110 °C to remove glycerol completely and most of FFAs; and the second distillation at optimized TE 155 °C; resulting in a stream distillate with 91% purity and 94% overall recovery of MAGs. This work also demonstrated that SPD is able to concentrate n-3 PUFAs in MAG form by distilling at proper TE e.g. 125 °C, where n-3 PUFAs are concentrated in the residues. Moreover, this work mapped out a complete processing diagram for scalable production of n-3 PUFAs enriched MAGs as potential food emulsifier and ingredient. Copyright © 2015 Elsevier Ltd. All rights reserved.
Joanna Silva Santos
2013-01-01
Full Text Available Omega-3 enriched partial acylglycerols are beneficial for human health. The aim of this study was to obtain monoacylglycerols (MAG and diacylglycerols (DAG by means of glycerolysis of fish oil catalyzed by a lipase from Rhizomucor miehei in the presence of food grade surfactants (Tween 65, 80 or 85. Glycerolysis was successful in the reaction media for all the tested surfactants, showing their potential for use as additives in such a system. The best results, however, were obtained for the reaction medium in the absence of surfactant whose peroxide value was the lowest after glycerolysis.
Joanna Silva Santos; Gisanara Dors; Débora de Oliveira; Soeli Francisca Mazzini Monte Blanco; José Vladimir de Oliveira; Agenor Furigo Júnior; Jorge Luiz Ninow; Maria Manuela Camino Feltes
2013-01-01
Omega-3 enriched partial acylglycerols are beneficial for human health. The aim of this study was to obtain monoacylglycerols (MAG) and diacylglycerols (DAG) by means of glycerolysis of fish oil catalyzed by a lipase from Rhizomucor miehei in the presence of food grade surfactants (Tween 65, 80 or 85). Glycerolysis was successful in the reaction media for all the tested surfactants, showing their potential for use as additives in such a system. The best results, however, were obtained for the...
Solaesa, Á. G.
2015-12-01
Full Text Available The production of monoacylglycerol rich in polyunsaturated fatty acids (PUFA via enzymatic glycerolysis of sardine oil in a homogeneous system was evaluated. Reactions were conducted in two different tert-alcohols. Based on the phase equilibrium data, the amount of solvent added to create a homogeneous system has been calculated and optimized. The immobilized lipase used in this work was Lipozyme RM IM from Rhizomucor miehei, a water dependent lipase. The amount of water added as well as other reaction parameters were studied to evaluate the optimum conditions for monoacylglycerol obtencion. An initial reactant mole ratio glycerol to sardine oil 3:1, 12 wt% of water based on glycerol content and 10 wt% of lipase loading (based on weight of reactants, achieved a MAG yield of around 70%, with nearly 28 wt% PUFA, with low free fatty acid content (lower than 18 wt%.En este trabajo se ha estudiado la producción de monoacilglicéridos, ricos en ácidos grasos poliinsaturados (AGPI, mediante glicerolisis enzimática de aceite de sardina. La reacción se ha llevado a cabo en dos tert-alcoholes para conseguir de esta forma un medio homogéneo de reacción. La cantidad de disolvente añadida al medio de reacción se ha optimizado y calculado en base al equilibrio de fases de los componentes del sistema. La lipasa empleada como biocatalizador ha sido la enzima inmovilizada Lipozyme RM IM de Rhizomucor miehei, una lipasa dependiente de agua. Se ha estudiado el efecto de distintos parámetros cinéticos, así como de la cantidad de agua añadida al medio de reacción, en la producción de monoacilglicéridos. De los resultados obtenidos, se puede concluir que, para una relación molar inicial de reactantes glicerol:aceite de sardina de 3:1, un 12 % en peso de agua en base al glicerol y un 10 % en peso de lipasa, en base al peso de reactantes; se puede llegar a conseguir un rendimiento en monoacilglicéridos alrededor del 70 % en peso, con casi un 28 % en
Cukurovali, Alaaddin; Yilmaz, Engin
2014-10-01
In this study, three new hydrazide-hydrazone derivative compounds which contain choloroacetyl group have been synthesized and characterized. In the characterization, spectral techniques such as IR, 1H NMR, 13C NMR and UV-Vis spectroscopy techniques were used. Antibacterial effects of the synthesized compounds were investigated against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. In the theoretical calculations Gaussian 09 software was used with the DFT/6-311+(d,p) basis set. Experimental X-ray analysis of compounds has not been studied. Theoretical bond lengths of synthesized compounds were compared with experimental bond lengths of a similar compound. Theoretical and experimental bond lengths are in good agreement with R2: 0.896, 0.899 and 0.900 for compounds 1, 2, and 3, respectively. For antibacterial activity, the most effective one was found to be N‧-(4-bromobenzylidene)-2-chloro-N-(4-(3-methyl-3-phenylcyclobutyl)-thiazol-2-yl) acetohydrazide against P.aeroginaosa ATTC 27853, among the studied compounds.
Xiaojin Li
2013-01-01
Full Text Available Previous studies have investigated both structural and functional brain networks via graph-theoretical methods. However, there is an important issue that has not been adequately discussed before: what is the optimal theoretical graph model for describing the structural networks of human brain? In this paper, we perform a comparative study to address this problem. Firstly, large-scale cortical regions of interest (ROIs are localized by recently developed and validated brain reference system named Dense Individualized Common Connectivity-based Cortical Landmarks (DICCCOL to address the limitations in the identification of the brain network ROIs in previous studies. Then, we construct structural brain networks based on diffusion tensor imaging (DTI data. Afterwards, the global and local graph properties of the constructed structural brain networks are measured using the state-of-the-art graph analysis algorithms and tools and are further compared with seven popular theoretical graph models. In addition, we compare the topological properties between two graph models, namely, stickiness-index-based model (STICKY and scale-free gene duplication model (SF-GD, that have higher similarity with the real structural brain networks in terms of global and local graph properties. Our experimental results suggest that among the seven theoretical graph models compared in this study, STICKY and SF-GD models have better performances in characterizing the structural human brain network.
Elaboration of a characterization map of scientific text: theoretical perspectives and application
Jane Raquel Silva de Oliveira
2015-03-01
Full Text Available The aim of this study is to present the theoretical perspectives that enabled the elaboration of a Characterization Map of Scientific Text and, in addition, to describe its application in the analysis of a research article published in the periodical Química Nova (Brazilian Chemical Society. The analysis revealed that the article exhibits the characteristics of the scientific text indicated on the map, verifying the appropriateness of the theoretical perspectives adopted in its elaboration: works of Latour (2000, Coracini (2007, Campanario (2004, and Oliveira e Queiroz (2007. We concluded that the Map is an analytical tool that allows structural and rhetorical features in scientific text to be identified. It can be used to help undergraduate chemistry students recognize many features of scientific language and improve their scientific writing. Finally, the map can be used as a tool for the assessment of scientific texts produced by students.
shahriar Ghammamy
2012-10-01
Full Text Available There is provided a nano aluminate complex that has a quaternary ammonium cation. This nano system has an equal molar ratio of Al to N that has been prepared by reaction of an organic salt R+X- such as [(CH34NBr], and a Lewis acid such as AlCl3, compounds. The synthesized compound was characterized by IR, Mass, X-Ray diffraction measurements. In addition, the structure of synthesized compound was optimized at the theoretical level of the Moller-Plesser perturbations of the second order (MP2, with LanL2DZ basis set and molecular specifications such as band length and angle were extracted using Gaussian 98 program. Theoretical data show good agreement with the experimental result.
Bai, Song; Jiang, Jun; Zhang, Qun; Xiong, Yujie
2015-05-21
Charge kinetics is highly critical in determining the quantum efficiency of solar-to-chemical conversion in photocatalysis, and this includes, but is not limited to, the separation of photoexcited electron-hole pairs, utilization of plasmonic hot carriers and delivery of photo-induced charges to reaction sites, as well as activation of reactants by energized charges. In this review, we highlight the recent progress on probing and steering charge kinetics toward designing highly efficient photocatalysts and elucidate the fundamentals behind the combinative use of controlled synthesis, characterization techniques (with a focus on spectroscopic characterizations) and theoretical simulations in photocatalysis studies. We first introduce the principles of various processes associated with charge kinetics that account for or may affect photocatalysis, from which a set of parameters that are critical to photocatalyst design can be summarized. We then outline the design rules for photocatalyst structures and their corresponding synthetic approaches. The implementation of characterization techniques and theoretical simulations in different steps of photocatalysis, together with the associated fundamentals and working mechanisms, are also presented. Finally, we discuss the challenges and opportunities for photocatalysis research at this unique intersection as well as the potential impact on other research fields.
Rufangura, Patrick; Sabah, Cumali
2016-12-01
This paper suggests a metamaterial (MTM) absorber structure to be used for efficiency improved solar cell. The proposed MTM absorber consists of the topmost three concentric circular ring resonators, and a ground metal plane sandwiched to the top layer with a dielectric spacer. Numerical simulation and theoretical (interference theory) studies on the proposed design show a wideband with near-perfect (>99%) absorption response in the visible frequency region of the solar spectrum. Thermal characterization of the suggested design is also conducted in order to investigate its absorption capability at different temperatures. The proposed MTM absorber design is believed to be an outstanding candidate toward high-efficiency solar photovoltaic cell.
A Theoretical Method for Characterizing Nonlinear Effects in Paul Traps with Added Octopole Field.
Xiong, Caiqiao; Zhou, Xiaoyu; Zhang, Ning; Zhan, Lingpeng; Chen, Yongtai; Chen, Suming; Nie, Zongxiu
2015-08-01
In comparison with numerical methods, theoretical characterizations of ion motion in the nonlinear Paul traps always suffer from low accuracy and little applicability. To overcome the difficulties, the theoretical harmonic balance (HB) method was developed, and was validated by the numerical fourth-order Runge-Kutta (4th RK) method. Using the HB method, analytical ion trajectory and ion motion frequency in the superimposed octopole field, ε, were obtained by solving the nonlinear Mathieu equation (NME). The obtained accuracy of the HB method was comparable with that of the 4th RK method at the Mathieu parameter, q = 0.6, and the applicable q values could be extended to the entire first stability region with satisfactory accuracy. Two sorts of nonlinear effects of ion motion were studied, including ion frequency shift, Δβ, and ion amplitude variation, Δ(C(2n)/C0) (n ≠ 0). New phenomena regarding Δβ were observed, although extensive studies have been performed based on the pseudo-potential well (PW) model. For instance, the |Δβ| at ε = 0.1 and ε = -0.1 were found to be different, but they were the same in the PW model. This is the first time the nonlinear effects regarding Δ(C(2n)/C0) (n ≠ 0) are studied, and the associated study has been a challenge for both theoretical and numerical methods. The nonlinear effects of Δ(C(2n)/C0) (n ≠ 0) and Δβ were found to share some similarities at q < 0.6: both of them were proportional to ε, and the square of the initial ion displacement, z(0)(2).
Theoretical and experimental characterization of TiO{sub 2} thin films deposited at oblique angles
Alvarez, R; Gonzalez-GarcIa, L; Romero-Gomez, P; Rico, V; Cotrino, J; Gonzalez-Elipe, A R; Palmero, A, E-mail: rafael.alvarez@icmse.csic.es [Instituto de Ciencia de Materiales de Sevilla (CSIC-Universidad de Sevilla). Av. Americo Vespucio 49, 41092 Sevilla (Spain)
2011-09-28
The microstructural features of amorphous TiO{sub 2} thin films grown by the electron beam physical vapour deposition technique at oblique angles have been experimentally and theoretically studied. The microstructural features of the deposited films were characterized by considering both the column tilt angle and the increase in the column thickness with height. A Monte Carlo model of film growth has been developed that takes into account surface shadowing, short-range interaction between the deposition species and the film surface, as well as the angular broadening of the deposition flux when arriving at the substrate. The good match between simulations and experimental results indicates the importance of these factors in the growth and microstructural development of thin films deposited at oblique angles.
Liu, Xiaomeng; Chen, Ben M
2012-01-01
This paper considers the controllability problem for multi-agent systems. In particular, the structural controllability of multi-agent systems under switching topologies is investigated. The structural controllability of multi-agent systems is a generalization of the traditional controllability concept for dynamical systems, and purely based on the communication topologies among agents. The main contributions of the paper are graph-theoretic characterizations of the structural controllability for multi-agent systems. It turns out that the multi-agent system with switching topology is structurally controllable if and only if the union graph G of the underlying communication topologies is connected (single leader) or leader-follower connected (multi-leader). Finally, the paper concludes with several illustrative examples and discussions of the results and future work.
EEG-fMRI based information theoretic characterization of the human perceptual decision system.
Dirk Ostwald
Full Text Available The modern metaphor of the brain is that of a dynamic information processing device. In the current study we investigate how a core cognitive network of the human brain, the perceptual decision system, can be characterized regarding its spatiotemporal representation of task-relevant information. We capitalize on a recently developed information theoretic framework for the analysis of simultaneously acquired electroencephalography (EEG and functional magnetic resonance imaging data (fMRI (Ostwald et al. (2010, NeuroImage 49: 498-516. We show how this framework naturally extends from previous validations in the sensory to the cognitive domain and how it enables the economic description of neural spatiotemporal information encoding. Specifically, based on simultaneous EEG-fMRI data features from n = 13 observers performing a visual perceptual decision task, we demonstrate how the information theoretic framework is able to reproduce earlier findings on the neurobiological underpinnings of perceptual decisions from the response signal features' marginal distributions. Furthermore, using the joint EEG-fMRI feature distribution, we provide novel evidence for a highly distributed and dynamic encoding of task-relevant information in the human brain.
Blur and illumination robust face recognition via set-theoretic characterization.
Vageeswaran, Priyanka; Mitra, Kaushik; Chellappa, Rama
2013-04-01
We address the problem of unconstrained face recognition from remotely acquired images. The main factors that make this problem challenging are image degradation due to blur, and appearance variations due to illumination and pose. In this paper, we address the problems of blur and illumination. We show that the set of all images obtained by blurring a given image forms a convex set. Based on this set-theoretic characterization, we propose a blur-robust algorithm whose main step involves solving simple convex optimization problems. We do not assume any parametric form for the blur kernels, however, if this information is available it can be easily incorporated into our algorithm. Furthermore, using the low-dimensional model for illumination variations, we show that the set of all images obtained from a face image by blurring it and by changing the illumination conditions forms a bi-convex set. Based on this characterization, we propose a blur and illumination-robust algorithm. Our experiments on a challenging real dataset obtained in uncontrolled settings illustrate the importance of jointly modeling blur and illumination.
Theoretical characterization of the gravity influence on the displacement flows in porous media
Rosa, Reinaldo; Baroni, Mariana; de Wit, Anne; Pontes, Jose; da Silva, Antonio
Structural characterization of miscible displacement in porous media (Hele-Shaw cell-type) is of special interest to understand, among several processes, fingering time evolution of gravitydriven thin coating films. When the heavy solution lies on top of the lighter one in the gravity field, a complex convective fingerlike deformation of the front is observed experimentally. In this paper, nonlinear interactions between chemical reactions and miscible density fingering are studied by direct numerical simulations taking into account different gravity conditions in a Darcy-Boussinesq system. The nonlinear pattern formation of the fingers for different values of g (the planetary gravitational acceleration) is characterized by two complementary analytical methods: linear stability analysis and gradient pattern analysis. Both methods are very sensitive to fine response of the fingering process when the gravitational field is slightly changed. Here, for the first time, is presented the theoretical fine variation of the density fingering fronts in a porous media as a function of the gravitational acceleration (we used typical values, in m/s2, at the surface of the known solar system planets (3.69, 4.00, 4.70, 8.75, 9.82, 9.89, 10.99, 11.08, 25.99). Finally, due to new discoveries, in reaction-diffusion processes, which have been made under space conditions, we discuss the importance of this result in future space missions under distinct planetary gravitational acceleration.
Majid Rezaeivala
2016-11-01
Full Text Available A new asymmetrical tripodal amine, [H3L2]Br3 containing morpholine moiety was prepared from reacting of one equivalent of N-(3-aminopropylmorpholine and two equivalents of tosylaziridine, followed by detosylation with HBr/CH3COOH. The products were characterized by various spectroscopic methods such as FAB-MS, elemental analysis, 1H and 13C NMR spectroscopy. The crystal structure of the hydrobromide salt of the latter amine, [H3L2]Br3, was also determined. For triprotonated form of the ligand L2 we can consider several microspecies and/or conformers. A theoretical study at B3LYP/6-31G∗∗ level of theory showed that the characterized microspecies is the most stable microspecies for the triprotonated form of the ligand. It was shown that the experimental NMR data for [H3L2]Br3 in solution have good correlation with the corresponding calculated data for the most stable microspecies of [H3L2]3+ in the gas phase.
Atahan-Evrenk, Sule; Aspuru-Guzik, Alán
2014-01-01
The theoretical prediction and characterization of the solid-state structure of organic semiconductors has tremendous potential for the discovery of new high performance materials. To date, the theoretical analysis mostly relied on the availability of crystal structures obtained through X-ray diffraction. However, the theoretical prediction of the crystal structures of organic semiconductor molecules remains a challenge. This review highlights some of the recent advances in the determination of structure-property relationships of the known organic semiconductor single-crystals and summarizes a few available studies on the prediction of the crystal structures of p-type organic semiconductors for transistor applications.
Zhang, Ning; Yang, Xue; Fu, Junning; Chen, Qiong; Song, Ziliang; Wang, Yong
2016-01-01
In this study, diacylglycerol-enriched soybean oil (DESO) was synthesized through Lipozyme 435-catalyzed glycerolysis of soybean oil (SO) in a solvent-free system using a modified bubble column reactor. The effects of enzyme load, mole ratio of glycerol to soybean oil, reaction temperature, gas flow and reaction time on DAG production were investigated. The selected conditions were established as being enzyme load of 4 wt% (mass of substrates), glycerol/soybean oil mole ratio of 20:1, reaction temperature of 80°C, gas flow of 10.6 cm/min, and a reaction time of 2.5 h, obtaining the DAG content of 49.4±0.5 wt%. The reusability of Lipozyme 435 was evaluated by monitoring the contents of DAG, monoacylglycerol (MAG) and triacylglycerol (TAG) in 10 consecutive runs. After purified by one-step molecular distillation, the DAG content of 63.5±0.3 wt% was achieved in DESO. The mole ratio of 1, 3-DAG to 1, 2-DAG was 2:1 and the fatty acid composition had no significant difference from that of soybean oil. However, the thermal properties of DESO and SO had considerable differences. Polymorphic form of DESO were mainly the β form and minor amounts of the β' form. Granular aggregation and round-shaped crystals were detected in DESO.
2015-01-01
Four new hydrazones were synthesized by the condensation of the selected hydrazine and the appropriate nitrobenzaldehyde. A complete characterization was done employing 1H- and 13C-NMR, electrochemical techniques and theoretical studies. After the characterization and electrochemical analysis of each compound, amoebicidal activity was tested in vitro against the HM1:IMSS strain of Entamoeba histolytica. The results showed the influence of the nitrobenzene group and the hydrazone linkage on th...
Abidian, Mohammad Reza; Martin, David C
2008-03-01
Neural prostheses transduce bioelectric signals to electronic signals at the interface between neural tissue and neural microelectrodes. A low impedance electrode-tissue interface is important for the quality of signal during recording as well as quantity of applied charge density during stimulation. However, neural microelectrode sites exhibit high impedance because of their small geometric surface area. Here we analyze nanostructured-conducting polymers that can be used to significantly decrease the impedance of microelectrode typically by about two orders of magnitude and increase the charge transfer capacity of microelectrodes by three orders of magnitude. In this study poly(pyrrole) (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) nanotubes were electrochemically polymerized on the surface of neural microelectrode sites (1250 microm(2)). An equivalent circuit model comprising a coating capacitance in parallel with a pore resistance and interface impedance in series was developed and fitted to experimental results to characterize the physical and electrical properties of the interface. To confirm that the fitting parameters correlate with physical quantities of interface, theoretical equations were used to calculate the parameter values thereby validating the proposed model. Finally, an apparent diffusion coefficient was calculated for PPy film (29.2+/-1.1 x 10(-6) cm(2)/s), PPy nanotubes (PPy NTs) (72.4+/-3.3 x 10(-6) cm(2)/s), PEDOT film (7.4+/-2.1 x 10(-6) cm(2)/s), and PEDOT nanotubes (PEDOT NTs) (13.0+/-1.8 x 10(-6) cm(2)/s). The apparent diffusion coefficient of conducting polymer nanotubes was larger than the corresponding conducting polymer films.
Fernandez, A.M.; Timon, V.; Cubero, J. J.; Sanchez-Ledesma, D. M.; Gutierrez-Nebot, L.; Martinez, J. J.; Romero, C.; Labajo, M.; Melon, A.; Barrios, I.
2013-10-01
New data about the physico-chemical, microstructural and crystal-chemical properties of the mineral paligorskite from Torrejon el Rubio (Caceres, Spain) were obtained by a combination of experimental techniques (XRD, FRX, FTIR, TG-DSC, SEM and chemical analyses), as well as geometry optimization by means of the Density Functional Theory (DFT). This study demonstrates the applicability of the mixed theoretical-experimental work to characterize and understand the properties of clay minerals used in technological applications and environmental remediation. (Author)
Puente, Norma P; Chaikina, Elena I; Herath, Sumudu; Yamilov, Alexey
2011-02-20
We present results of experimental and theoretical studies of polarization-resolved light transmission through optical fiber with disorder generated in its germanium-doped core via UV radiation transmitted through a diffuser. In samples longer than a certain characteristic length, the power transmitted with preserved polarization is observed to be distributed over all forward-propagating modes, as evidenced by the Rayleigh negative exponential distribution of the near-field intensity at the output surface of the fiber. Furthermore, the transmitted power becomes also equally distributed over both polarizations. To describe the optical properties of the fibers with the experimentally induced disorder, a theoretical model based on coupled-mode theory is developed. The obtained analytical expression for the correlation function describing spatial properties of the disorder shows that it is highly anisotropic. Our calculations demonstrate that this experimentally controllable anisotropy can lead to suppression of the radiative leakage of the propagating modes, so that intermode coupling becomes the dominant scattering process. The obtained theoretical expressions for the polarization-resolved transmission fit very well with the experimental data, and the information extracted from the fit shows that radiative leakage is indeed small. The reported technique provides an easy way to fabricate different configurations of controlled disorder in optical fibers suitable for such applications as random fiber lasers.
李道明; 王卫飞; 蓝东明; 杨博; 王永华
2014-01-01
利用4种常用大孔树脂(NKA-9,AB-8,D301R,D4020)对Lipozyme TL 100L进行固定化,并比较了固定化效果及4种固定化脂肪酶对甘油解反应制备甘油二酯的影响。结果表明：以弱极性大孔吸附树脂AB-8为载体固定化的Lipozyme TL 100 L在无溶剂体系中催化大豆油甘油解反应制备甘油二酯的效率最高；当底物(精炼大豆油与甘油)摩尔比为1∶2,反应温度为50℃,AB-8大孔树脂固定化的Lipozyme TL 100L加酶量为600 U/g时,在甘油解反应6 h后产物中甘油二酯含量基本达到平衡,为54.39%,其中1,2-甘油二酯含量为33.87%,1,3-甘油二酯含量为20.52%。%Lipozyme TL 100 L was immobilized by four kinds of common macroporous resins ( NKA-9 , AB-8,D301R,D4020). The immobilization effects of the four kinds of common macroporous resins were compared,and the impacts of four kinds of the immobilized lipases on synthesis of diglycerides by glycer-olysis were also compared. The results showed that immobilized Lipozyme TL 100L with macroporous res-in AB-8 as carrier had the highest catalytic efficiency in synthesis of diglycerides by glycerolysis of soy-bean oil in a solvent free system. When dosage of immobilized Lipozyme TL 100L with macroporous resin AB-8 as carrier was 600 U/g,molar ratio of refined soybean oil to glycerol was 1∶2 and reaction temper-ature was 50℃,the content of diglycerides in the product reached 54. 39% after glycerolysis for 6 h,in which the contents of 1 ,2-diacylglycerol and 1 ,3-diacylglycerol were 33 . 87% and 20 . 52% respec-tively.
Characterization of Linearly Separable Boolean Functions: A Graph-Theoretic Perspective.
Rao, Yanyi; Zhang, Xianda
2016-04-05
In this paper, we present a novel approach for studying Boolean function in a graph-theoretic perspective. In particular, we first transform a Boolean function f of n variables into an induced subgraph Hf of the n-dimensional hypercube, and then, we show the properties of linearly separable Boolean functions on the basis of the analysis of the structure of Hf. We define a new class of graphs, called hyperstar, and prove that the induced subgraph Hf of any linearly separable Boolean function f is a hyperstar. The proposal of hyperstar helps us uncover a number of fundamental properties of linearly separable Boolean functions in this paper.
A Lattice-Theoretic Characterization of Optimal Minimum-Distance Linear Precoders
Kapetanovic, D; Mow, W H; Rusek, F
2012-01-01
This work investigates linear precoding over non-singular linear channels with additive white Gaussian noise, with lattice-type inputs. The aim is to maximize the minimum distance of the received lattice points, where the precoder is subject to an energy constraint. It is shown that the optimal precoder only produces a finite number of different lattices, namely perfect lattices, at the receiver. The well-known densest lattice packings are instances of perfect lattices, however it is analytically shown that the densest lattices are not always the solution. This is a counter-intuitive result at first sight, since previous work in the area showed a tight connection between densest lattices and minimum distance. Since there are only finitely many different perfect lattices, they can theoretically be enumerated off-line. A new upper bound on the optimal minimum distance is derived, which significantly improves upon a previously reported bound. Based on this bound, we propose an enumeration algorithm that produces...
Kashinski, D. O.; Nelson, R. G.; Chase, G. M.; di Nallo, O. E.; Byrd, E. F. C.
2016-05-01
We are investigating the accuracy of theoretical models used to predict the visible, ultraviolet, and infrared spectra, as well as other properties, of product materials ejected from the muzzle of currently fielded systems. Recent advances in solid propellants has made the management of muzzle signature (flash) a principle issue in weapons development across the calibers. A priori prediction of the electromagnetic spectra of formulations will allow researchers to tailor blends that yield desired signatures and determine spectrographic detection ranges. Quantum chemistry methods at various levels of sophistication have been employed to optimize molecular geometries, compute unscaled harmonic frequencies, and determine the optical spectra of specific gas-phase species. Electronic excitations are being computed using Time Dependent Density Functional Theory (TD-DFT). Calculation of approximate global harmonic frequency scaling factors for specific DFT functionals is also in progress. A full statistical analysis and reliability assessment of computational results is currently underway. Work supported by the ARL, DoD-HPCMP, and USMA.
A Theoretical Characterization of Curvature Controlled Adhesive Properties of Bio-Inspired Membranes
Afferante, Luciano; Heepe, Lars; Casdorff, Kirstin;
2016-01-01
Some biological systems, such as the tree frog, Litoria caerulea, and the bush-cricket, Tettigonia viridissima, have developed the ability to control adhesion by changing the curvature of their pads. Active control systems of adhesion inspired by these biological models can be very attractive...... for the development of devices with controllable adhesive properties. In this paper, we present a theory describing the adhesive behavior of an artificial system consisting of an inflatable membrane clamped to a metallic cylinder and filled with air. In such a system, by controlling the internal pressure acting...... on the membrane, it is possible to modulate the adhesive strength. In particular, an increase of the internal pressure and, hence, the curvature of the membrane, results in a decrease of the pull-off force. Results predicted by the theoretical model are in good agreement with experimental data. The model explains...
Rebello, Carina M.; Rebello, N. Sanjay
2012-02-01
Previous studies have focused on the resources that students activate and utilize while solving a given physics problem. However, few studies explore how students relate a given resource such as an equation, to various types of physics problems and contexts and how they ascertain the meaning and applicability of that resource. We explore how students view physics equations, derive meaning from those equations, and use those equations in physics problem solving. We adapt Dubinsky and McDonald's description of APOS (action-process-object-schema) theory of learning in mathematics, to construct a theoretical framework that describes how students interpret and use equations in physics in terms of actions, processes, objects, and schemas. This framework provides a lens for understanding how students construct their understanding of physics concepts and their relation to equations. We highlight how APOS theory can be operationalized to serve as a lens for studying the use of mathematics in physics problem solving.
Larissa Freitas
2013-06-01
Full Text Available Different strategies to avoid the lipid feedstock oxidation in the enzymatic synthesis of monoglycerides (MAG from glycerolysis of babassu oil were tested. The reactions were catalyzed by Burkholderia cepacia lipase immobilized on SiO2-PVA and the tests carried out in batchwise. The best strategy was tested in a continuous packed-bed reactor. Different antioxidants and emulsifiers were used, including: Buthyl-hydroxy-toluene (BHT, tocopherol, soy lecithin and Triton X-100. The influence of inert atmosphere (N2 on the MAG production was also investigated. Results were compared with those attaining in the control reaction. The best performance was obtained using N2 in the reaction medium, preventing the oxidation of babassu oil. MAG concentrations were 60 and 24% in batch and continuous mode, respectively. Among the tested antioxidant and emulsifying agents, only soy lecithin was found to be efficient but its application showed limit performance to be used in continuous runs.
Zhang, Junlin; Liu, Yingzhe; Bi, Fuqiang; Zhou, Jing; Wang, Bozhou
2017-08-01
Three novel Bn-protected tricyclic multiple(urea) molecules were synthesized and characterized by 1H NMR, 13C NMR, FT-IR and elementary analysis. Structures of the Bn-protected tricyclic tris(urea) and bis(urea) molecules were further characterized by X-ray single-crystal diffraction analysis, indicating the urea carbonyl group has great influence on the molecular conformation and chemical reactivity. The electrostatic potentials on isosurfaces of electron density of the crystal structures obtained were studied by B3LYP/6-311G(d,p) method and Hirshfeld surface analysis were carried out to identify and quantify the interaction nature and proportion in crystals.
Mohanty, Rakesh; Tripathy, Sasmita
2011-01-01
List Accessing Problem is a well studied research problem in the context of linear search. Input to the list accessing problem is an unsorted linear list of distinct elements along with a sequence of requests, where each request is an access operation on an element of the list. A list accessing algorithm reorganizes the list while processing a request sequence on the list in order to minimize the access cost. Move-To-Front algorithm has been proved to be the best performing list accessing online algorithm till date in the literature. Characterization of the input request sequences corresponding to practical real life situations is a big challenge for the list accessing problem. As far as our knowledge is concerned, no characterization for the request sequences has been done in the literature till date for the list accessing problem. In this paper, we have characterized the request sequences for the list accessing problem based on several factors such as size of the list, size of the request sequence, ordering...
Albooyeh, M.; Tretyakov, Sergei [Department of Radio Science and Engineering, Aalto University, P.O. Box 13000, FI-00076, Aalto (Finland); Simovski, Constantin [Department of Radio Science and Engineering, Aalto University, P.O. Box 13000, FI-00076, Aalto (Finland); Laboratory of Metamaterials, University for Information Technology, Mechanics and Optics (ITMO), 197101, St. Petersburg (Russian Federation)
2016-10-15
We present a general methodology for electromagnetic homogenization and characterization of bianisotropic metasurfaces formed by regular or random arrangements of small arbitrary inclusions at interfaces of two different isotropic media. The approach unites and generalizes the earlier theories developed independently by two joint research groups: that of profs. Holloway and Kuester and that of profs. Simovski and Tretyakov. We analyze the features of both formalisms and discuss their peculiarities in several example cases. Our theory can be used in the analysis and synthesis of a wide spectrum of metasurfaces. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Dalbouha, S., E-mail: samiradalbouha@gmail.com; Senent, M. L., E-mail: senent@iem.cfmac.csic.es [Departamento de Química y Física Teóricas, Instituto de Estructura de la Materia, IEM-C.S.I.C., Serrano 121, Madrid 28006 (Spain); Komiha, N., E-mail: komiha@fsr.ac.ma [LS3ME-Équipe de Chimie Théorique et Modélisation, Faculté des Sciences, Université Mohamed V—Agdal, Rabat (Morocco)
2015-02-21
The low temperature spectra of the detectable species methyl hydroperoxide (CH{sub 3}OOH) and three sulfur analogs, the two isomers of methanesulfenic acid (CH{sub 3}SOH and CH{sub 3}OSH) and the methyl hydrogen disulfide (CH{sub 3}SSH), are predicted from highly correlated ab initio methods (CCSD(T) and CCSD(T)-F12). Rotational parameters, anharmonic frequencies, torsional energy barriers, torsional energy levels, and their splittings are provided. Our computed parameters should help for the characterization and the identification of these organic compounds in laboratory and in the interstellar medium.
Chan, R W; Titze, I R
2000-01-01
The viscoelastic shear properties of human vocal fold mucosa (cover) were previously measured as a function of frequency [Chan and Titze, J. Acoust. Soc. Am. 106, 2008-2021 (1999)], but data were obtained only in a frequency range of 0.01-15 Hz, an order of magnitude below typical frequencies of vocal fold oscillation (on the order of 100 Hz). This study represents an attempt to extrapolate the data to higher frequencies based on two viscoelastic theories, (1) a quasilinear viscoelastic theory widely used for the constitutive modeling of the viscoelastic properties of biological tissues [Fung, Biomechanics (Springer-Verlag, New York, 1993), pp. 277-292], and (2) a molecular (statistical network) theory commonly used for the rheological modeling of polymeric materials [Zhu et al., J. Biomech. 24, 1007-1018 (1991)]. Analytical expressions of elastic and viscous shear moduli, dynamic viscosity, and damping ratio based on the two theories with specific model parameters were applied to curve-fit the empirical data. Results showed that the theoretical predictions matched the empirical data reasonably well, allowing for parametric descriptions of the data and their extrapolations to frequencies of phonation.
Liping Wen
2012-01-01
Full Text Available Fe-doped TiO2 was prepared by hydrothermal treating Ti peroxide sol with different amount of iron nitrate. Fe ions can enter TiO2 lattice by substituting Ti4+ ions, which significantly affect the crystallinity and morphology of TiO2 nanoparticles. Fe doping also influences the UV-Vis absorption and photoluminescence of TiO2, due to the change of electronic structure. It is shown that Fe ions are more easily doped on TiO2 surface than in bulk. The theoretical computation based on the density functional theory (DFT shows that the Fe ions in TiO2 bulk are localized and mainly act as the recombination centers of photoinduced electrons and holes. Some results support that the Fe3+ ions on surface can form intermediate interfacial transfer pathway for electrons and holes, which is beneficial for increasing the photocatalytic activity of TiO2. The photocatalytic activity first increases and then decreases as the Fe concentration increases, which is coaffected by the bulk-doped and surface-doped Fe ions.
Borah, B
2014-01-01
A theoretical model is developed to study the equilibrium electromagnetic properties of a spherically symmetric dust molecular cloud (DMC) structure on the Jeans scale. It applies a technique based on the modified Lane-Emden equation (m-LEE). It considers an inhomogeneous distribution of dust grains in field-free hydrodynamic equilibrium configuration within the framework of exact gravito-electrostatic pressure balancing condition. Although weak relative to the massive grains, but finite, the efficacious inertial roles of the thermal species (electrons and ions) are included. A full portrayal of the lowest-order cloud surface boundary (CSB) and associated parameter signatures on the Jeans scale is made numerically for the first time. The multi-order extremization of the m-LEE solutions specifies the CSB at a radial point m relative to the centre. It gets biased negatively due to the interplay of plasma-boundary wall interaction (global) and plasma sheath-sheath coupling (local) processes. The CSB acts as an i...
Rajasekar, M.; Muthu, K.; Aditya Prasad, A.; Meenakshisundaram, S. P.
2015-04-01
Single crystals of tris(allylthiourea)mercury(II) chloride (TATMC) have been grown by slow evaporation solution growth technique. It belongs to the trigonal system with noncentrosymmetric space group R3c and the cell parameters are, a = b = 11.4443(3) Å, c = 28.1142(6) Å, V = 3188.85(14) Å3, α = β = 90°, γ = 120° and Z = 6. Powder X-ray diffraction pattern reveals the crystallinity of the as-grown specimen and it closely resembles the simulated one from the single crystal XRD data. Good reflectance in the visible region is observed and the band gap energy is estimated using diffuse reflectance data by the application of Kubelka-Munk algorithm. The functional groups are identified by Fourier transform infrared spectral analysis and compared with theoretical spectrum. The crystal is stable up to the melting point and the mechanistic behavior is ascertained by microhardness studies. The second harmonic generation efficiency of TATMC is estimated by Kurtz and Perry powder technique. The first-order molecular hyperpolarizabilities of some tris(allylthiourea) complexes have been evaluated using density functional theory (DFT) employing B3LYP functional, LanL2DZ as basis set and results rationalized. The optimized geometry closely resembles the ORTEP. The Hirshfeld surface analysis is carried out using HF method with 3-21G as basis set. Investigation of the intermolecular interactions and crystal packing via Hirshfeld surface analysis, derived by single crystal XRD data, reveals the close contacts associated with strong interactions.
Viani, Lucas; Olivier, Yoann; Athanasopoulos, Stavros; da Silva Filho, Demetrio A; Hulliger, Jürg; Brédas, Jean-Luc; Gierschner, Johannes; Cornil, Jérôme
2010-04-06
A great deal of interest has recently focused on host-guest systems consisting of one-dimensional collinear arrays of conjugated molecules encapsulated in the channels of organic or inorganic matrices. Such architectures allow for controlled charge and energy migration processes between the interacting guest molecules and are thus attractive in the field of organic electronics. In this context, we characterize here at a quantum-chemical level the molecular parameters governing charge transport in the hopping regime in 1D arrays built with different types of molecules. We investigate the influence of several parameters (such as the symmetry of the molecule, the presence of terminal substituents, and the molecular size) and define on that basis the molecular features required to maximize the charge carrier mobility within the channels. In particular, we demonstrate that a strong localization of the molecular orbitals in push-pull compounds is generally detrimental to the charge transport properties.
Oliveira, Ramon Prata; Demuner, Antonio Jacinto; Alvarenga, Elson Santiago; Parma, Monica Cropo; Barbosa, Luiz Claudio Almeida; de Moura Guimarães, Luciano; Aguiar, Alex Ramos
2017-05-01
The use of plants in folk medicine has a long and ancient history in the treatment of various diseases. Currently, a large proportion of commercial drugs are based on natural products or are synthetic compounds inspired on such natural substances. Therefore, in this communication to aid that research, structural and spectroscopic analysis of the natural pyrrolizidine alkaloid called monocrotaline was carried out. Pyrrolizidine alkaloids that are commonly found in the Boraginaceae and Asteraceae families are among the great diversity of secondary metabolites which are produced by plants to act as a defense mechanism against herbivores and microbes. In the present study, the natural product, monocrotaline, an alkaloid isolated from the leaves of Crotalaria paulina, with potential application in medicine, was characterized by infrared (IR) and Raman spectroscopy with the support of Density Functional Theory (DFT) calculations. IR and Raman spectra of monocrotaline were recorded at room temperature ranging from 4000 to 400 cm-1. DFT calculations with the hybrid functional B3LYP and the basis set 6-31 + G(d,p) were performed with the purpose of obtaining information on the structural and vibrational properties of this structure. A perfect fit between the experimentally measured frequencies of the IR and Raman spectra and the calculated values were observed, and we have performed the complete identification of monocrotaline by these techniques.
Khalaji, A. D., E-mail: alidkhalaji@yahoo.com [Golestan University, Department of Chemistry, Faculty of Science (Iran, Islamic Republic of); Maddahi, E. [Iran University of Science & Technology, Ms.C Educated, Department of Chemistry (Iran, Islamic Republic of); Dusek, M.; Fejfarova, K. [Institute of Physics of the ASCR, v.v.i. (Czech Republic); Chow, T. J. [Academia Sinica, Institute of Chemistry (China)
2015-12-15
Metal-free organic compounds 24-SC ((E)-2-cyano-3-(2,4-dimethoxyphenyl)acrylic acid) and 34-SC ((E)-2-cyano-3-(3,4-dimethoxyphenyl)acrylic acid), containing methoxy groups as a donor and the acrylic acid as an acceptor were synthesized and characterized by CHN, FT-IR, UV-Vis, {sup 1}H-NMR and single crystal X-ray diffraction and used as photosensitizers for the application of dye-sensitized solar cells (DSSC). The sensitizing characteristics of them were evaluated. Both compounds contain the natural molecule, its anionic form and the piperidinium cation and they differ by number of these molecules in the asymmetric unit. To get further insight into the effect of molecular structure on the performance of DSSC, their geometry and energies of HOMO and LUMO were optimized by density functional theory calculation at the B3LYP/6-31G(d) level with Gaussian 03. Overall conversion efficiencies of 0.78 under full sunlight irradiation are obtained for DSSCs based on the new metal-free organic dyes 24-SC and 34-SC.
Arroyo, E.; Luque, P. A.; Cosio, M.; Soto, C.; Villarreal, R.; Nava, O.; Olivas, A.
2017-06-01
This work reports the profiles of drug release systems based on different polymers for the potential use as a skin anti-inflammatory. The materials used for the encapsulation of indomethacin were Pluronic P123 with various combinations of poly-ethylene-glycol and poly-N-vinyl pyrrolidone. These systems were characterized via Fourier transform infrared spectrometry and high resolution transmission electron microscopy. The morphology showed the treated polymers as spheres. Drug loadings were carried out via the absorption in solution method; this load was of a 1:10 wt ratio indomethacin to polymers. Drug release tests were performed via the dialysis method pH 7.2 phosphate buffered saline at 32 °C. The drug concentration was determined via UV-Vis spectroscopy, and additionally, a theoretical model was developed based on diffusion equations to describe the phenomenon. Comparison between the experimental results and theory was close to 5%.
Toozandejani, Tina; Beyramabadi, S. Ali; Chegini, Hamed; Khashi, Maryam; Morsali, Ali; Pordel, Mehdi
2017-01-01
Herein, hopping to biological and catalytic applications, synthesis of a Mn(II) complex of the N,N‧-dipyridoxyl(1,2-diaminobenzene) [Hdbnd 2L] Schiff-base has been reported. The Mn complex was characterized experimentally and theoretically. The optimized geometry and vibrational frequencies of the complex were computed by using the density functional theory (DFT) methods. In the optimized geometry of the octahedral complex, the dianionic L2- acts as a tetradentate ligand. Four coordination positions of the square plane have been occupied with two azomethine nitrogens and two phenolic oxygens of the L2- ligand. Two coordinated methanol ligands are perpendicular to the square plane. Also, properties of the Mnsbnd N and Mnsbnd O bonds were explored investigated using the Atoms in molecules (AIM) analysis.
Dege, Necmi; Senyüz, Nuray; Batı, Hümeyra; Günay, Nergin; Avcı, Davut; Tamer, Ömer; Atalay, Yusuf
2014-01-01
In this study, we reported a combined experimental and theoretical study on nicotinic acid [1-(2,3-dihydroxyphenyl)methylidene]hydrazide (C13H11N3O3) molecule. The title compound was prepared and characterized by 1H and 13C FT-NMR, FT-IR and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/c with a=6.2681(3) Å, b=16.5309(7) Å, c=12.4197(6) Å, α=90°, β=111.603(4)°, γ=90° and Z=4. In addition, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO), continuous set of gauge transformations (CSGT), individual gauges for atoms in molecules (IGAIM) 1H and 13C NMR chemical shift values, natural bond orbital (NBO), nonlinear optical (NLO) and HOMO-LUMO analyses, molecular electrostatic potentials (MEPs) and thermodynamic properties of the title compound in the ground state were investigated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with 6-311++G(d,p). Besides, the hardness and electronegativity parameters were obtained from HOMO and LUMO energies. Obtained results indicate that there is a good agreement between the experimental and theoretical data.
Yanis Toledano-Magaña
2015-05-01
Full Text Available Four new hydrazones were synthesized by the condensation of the selected hydrazine and the appropriate nitrobenzaldehyde. A complete characterization was done employing 1H- and 13C-NMR, electrochemical techniques and theoretical studies. After the characterization and electrochemical analysis of each compound, amoebicidal activity was tested in vitro against the HM1:IMSS strain of Entamoeba histolytica. The results showed the influence of the nitrobenzene group and the hydrazone linkage on the amoebicidal activity. meta-Nitro substituted compound 2 presents a promising amoebicidal activity with an IC50 = 0.84 μM, which represents a 7-fold increase in cell growth inhibition potency with respect to metronidazole (IC50 = 6.3 μM. Compounds 1, 3, and 4 show decreased amoebicidal activity, with IC50 values of 7, 75 and 23 µM, respectively, as a function of the nitro group position on the aromatic ring. The observed differences in the biological activity could be explained not only by the redox potential of the molecules, but also by their capacity to participate in the formation of intra- and intermolecular hydrogen bonds. Redox potentials as well as the amoebicidal activity can be described with parameters obtained from the DFT analysis.
龚旭; 谷克仁
2011-01-01
The development of lipase - catalyzed glycerolysis of oil to synthesize monoglycerides in supercritical carbon dioxide was discussed.The effects of reaction temperature, pressure, water content, substrate ratio and activity of lipase on reaction were analyzed.This method had several advantages, such as lower reaction temperature, better color of the product, no solvent residues and simpler procedures, so it would be a potential method to produce food grade monoglycerides.%论述了超临界CO2条件下脂肪酶催化甘油解制备单甘酯的研究进展,并从反应温度、压力、含水量、底物比例、脂肪酶活性等方面对反应的影响进行了探讨.此法具有反应温度低,产品色泽好,无溶剂残留,操作步骤大大简化等优点,有望成为食品用单甘酯最有潜力的生产方法.
Heluani, S P
2002-01-01
Employing the invariant embedding principle, theoretical expressions for the detected characteristic X-ray intensities generated in electron probe microanalysis of thin films are obtained. Characteristic X-ray emission from the elements present in a solid is calculated from the probabilities of the backscattered and transmitted electron trajectories within the film and the substrate. The theoretical expressions mentioned provide for the possibility of developing procedures for microanalysis directly from the experimental results without making approaches for the estimation of the phi(rho z) function. The procedure used permits to calculate the recorded X-rays as a function of incident beam voltage and also as a function of the sample thickness. The method presented here gives the possibility of obtaining calibration curves for thin films and multi-layers. The results obtained are found to agree with experimental ones.
Agramunt Chaler, S.; Jurado Bruggeman, D.; Munoz Montplet, C.
2013-07-01
This work intends to check that the characterization of the spatial profiles obtained by a an intraoperative probe in the presence of a point source is possible enough making use only of the parameters down time sensitivity and opening of the collimator. (Author)
Matos, Maria J.; Uriarte, Eugenio; Santana, Lourdes; Vilar, Santiago
2013-06-01
Compounds 1 (4-methyl-N-(coumarin-3-yl)benzamide) and 2 ((coumarin-3-yl)-4-methylbenzoate) were synthesized by linking the coumarin system (3-aminocoumarin or 3-hydroxycoumarin, respectively) to a p-toluoylchloride. 1H and 13C NMR and X-ray diffractometry determined the molecular structures of both derivatives. The X-ray results were compared to those obtained by conformational analysis followed by semiempirical methodologies (AM1 and PM3). The theoretical calculations yielded results reproducing the whole three-dimensional (3D) structure of both molecules in a good agreement with X-ray structural analysis. The global structures of the two compounds are very similar in the two studied environments, meaning that the structural determination in the gas phase can be extrapolated. A comparative study between compounds 1 and 2, based on the structural results, was carried out.
Romanowski, Stela Maris de M.; Friedermann, Geraldo R.; Mangrich, Antonio S.; Hermann, Monique de F.; Nakagaki, Shirley, E-mail: shirley@quimica.ufpr.b [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica; Machado, Sergio P.; Lima, Hugo Orofino [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica
2010-07-01
The synthesis and characterization of the manganese(II) complexes [Mn{sup II}(Hbpeten)] and [Mn{sup II}(Hbnbpeten)], where H{sub 3}bpeten and H{sub 3}bnbpeten are respectively [N,N'-bis-(2-hydroxybenzyl)- N-(2-pyridylmethyl)-N'-(2-hydroxyethyl)ethane-1,2-diamine] and [N,N'-bis-(5-nitro-2- hydroxybenzyl)-N'-(2-hydroxyethyl)ethane-1,2-diamine], are reported. The characterization was carried out by elemental analyses, cyclic voltammetry, spectroscopic methods (UV-Vis, FTIR, {sup 1}H NMR), electronic paramagnetic resonance spectroelectrochemistry (EPR) and theoretical DFT calculations. The electrochemistry and EPR spectroelectrochemistry data were consistent with the reduction of one of the nitro groups in free H{sub 3}bnbpeten and in the respective manganese(II) complex. These results were supported by DFT calculations, which showed that only one nitro group contributes to the LUMO. The theoretical data appear to be suitable to describe the electronic properties of the compounds. (author)
Experimental and theoretical characterization of Cu adsorption sites on the Si(1 1 1)-7 × 7 surface
Mutombo, P.; Shukrinov, P.; Cháb, V.
2005-06-01
Scanning tunneling microscopy (STM) experiments were used to study Cu adsorption on Si(1 1 1)-7 × 7. The experimental results suggest that Cu atoms appear as dark spots while Si adatoms adjacent to them are imaged as gray or bright protrusions in the filled states images. We observed a mutual contrast reversal in the empty states between these bright and gray spots. Based on these experimental findings, we propose that Cu is located below the Si adatom layer. In order to verify this hypothesis, we performed total energy calculations and simulated STM maps by means of Density Functional Calculations. We tested different chemisorption geometries of Cu on the Si surface: on top of a rest atom and a corner adatom, at the so-called T 4 and H 3 sites as well as at positions situated halfway between the above adsorption positions. The theoretical results lead to the conclusion that Cu is located between the T 4 and H 3 adsorption sites.
Experimental and theoretical characterization of the 2(2)A'-1(2)A' transition of BeOH/D.
Mascaritolo, Kyle J; Merritt, Jeremy M; Heaven, Michael C; Jensen, Per
2013-12-19
The hydroxides of Ca, Sr, and Ba are known to be linear molecules, while MgOH is quasilinear. High-level ab initio calculations for BeOH predict a bent equilibrium structure with a bond angle of 140.9°, indicating a significant contribution of covalency to the bonding. However, experimental confirmation of the bent structure is lacking. In the present study, we have used laser excitation techniques to observe the 2(2)A'-1(2)A' transition of BeOH/D in the energy range of 30300-32800 cm(-1). Rotationally resolved spectra were obtained, with sufficient resolution to reveal spin splittings for the electronically excited state. Two-color photoionization was used to determine an ionization energy of 66425(10) cm(-1). Ab initio calculations were used to guide the analysis of the spectroscopic data. Multireference configuration interaction calculations were used to construct potential energy surfaces for the 1(2)A', 2(2)A', and 1(2)A" states. The rovibronic eigenstates supported by these surfaces were determined using the Morse oscillator rigid bender internal dynamics Hamiltonian. The theoretical results were in sufficiently good agreement with the experimental data to permit unambiguous assignment. It was confirmed that the equilibrium geometry of the ground state is bent and that the barrier to linearity lies below the zero-point energies for both BeOH and BeOD.
Antanovich, Artsiom; Prudnikau, Anatol; Gurin, Valerij; Artemyev, Mikhail, E-mail: m_artemyev@yahoo.com
2015-07-09
Highlights: • HgSe magic-sized clusters were prepared via Cd/Hg cationic exchange in pyridine. • Upon cationic exchange CdSe clusters behave differently from quantum dots or rods. • Theoretical calculations of magic-sized clusters agree well with experimental data. - Abstract: We examine conversion of magic-sized CdSe clusters (MSCs) into HgSe ones by means of Cd/Hg cation exchange. With this procedure Cd{sub 8}Cd{sub 17}– and Cd{sub 32}–selenide clusters can be converted into corresponding Hg{sub 8}–, Hg{sub 17}– and Hg{sub 32}–selenide ones. Upon cationic exchange MSCs behavior differs from that of bulkier counterparts – larger (2–3 nm) quantum dots. Unlike CdSe colloidal quantum dots, magic-sized clusters are converted in fast and complete manner without a formation of intermediate mixed Cd{sub x}Hg{sub 1−x} compounds that was established on the basis of optical absorption spectroscopy and chemical composition analysis. These assumptions were supported by DFT quantum chemical calculations performed for Cd{sub 8}–, Cd{sub 17}– and Hg{sub 8}–, Hg{sub 17}–selenide model clusters. Energies of experimental and calculated optical transitions were compared in order to prove the isostructural character of cationic substitution in magic-sized clusters.
Moroz, E. [Univ. of Texas at El Paso, Dept. of Mechanical and Industrial Engineering, El Paso, TX (United States)
1997-12-31
An experimental investigation into the acoustic noise from a small (7.6 m diameter) teetered rotor wind turbine, set at various yaw angles up to 90 degrees of yaw, was conducted. The results revealed a 1/3 octave spectra which was dominated by a broad peak in the higher frequency range, at all yaw angles investigated. This prompted a theoretical investigation to reveal the mechanisms producing the dominant feature in the experimentally obtained noise spectra and resulted in the development of a wind turbine aerodynamic noise prediction coce, WTNOISE. The location near busy roads and the relatively rough terrain of the wind test site caused difficulties in obtaining useful noise spectral information below 500Hz. However, sufficiently good data was obtained above 500Hz to clearly show a dominant `hump` in the spectrum, centered between 3000 and 4000Hz. Although the local Reynolds number for the blade elements was around 500,000 and one might expect Laminar flow over a significant portion of the blade, the data did not match the noise spectra predicted when Laminar flow was assumed. Given the relatively poor surface quality of the rotor blades and the high turbulence of the test site it was therefore assumed that the boundary layer on the blade may have tripped relatively early and that the turbulent flow setting should be used. This assumption led to a much better correlation between experiment and predictions. The WTNOISE code indicated that the broad peak in the spectrum was most likely caused by trailing edge bluntness noise. Unfortunately time did not allow for modifications to the trailing edge to be investigated. (au)
Ghasemian, Motaleb; Kakanejadifard, Ali; Karami, Tahereh
2016-11-01
The azo-azomethine dyes with a different substitution have been designed from the reaction of 4,4‧-diaminodiphenyl sulfone with 2-hydroxy-5-(aryldiazenyl)benzaldehyde. The compounds have been characterized by elemental analysis, Mass, IR, UV-Vis, TGA-DTA and NMR spectroscopy. The solvatochromism behaviors, effects of substitution and pH on the electronic absorption spectra of dyes were evaluated. The in vitro antimicrobial activities were also screened for their potential for antibiotic activities by broth micro dilution method. Also, the optimum molecular geometries, molecular electrostatic potential (MEP), nucleus-independent chemical shift (NICS) and frontier molecular orbitals (FMO), vibrational spectra (IR) and electronic absorption (UV-Vis) spectra of the title compounds have been investigated with the help of DFT and TDDFT methods with 6-311 ++G(d,p) basis sets and PCM calculations. The results of the calculations show excellent agreement with the experimental value.
Patricia Bogalhos Lucente Fregolente
2009-01-01
Full Text Available Monoacilglycerides and diacilglycerides are produced through lipase-catalyzed glycerolysis of soybean oil using Candida antarctica B in a solvent-free system. The reaction was carried out at a glycerol to triacylglycerol molar ratio of 8:1 with 2% of lipase. Acylglycerides, free fatty acids (FFA and glycerol produced were separated employing the molecular distillation process. Starting from a product of enzymatic reaction 25.06% of triacylglycerols, 46.63% of diacylglycerides, 21.72% of monoacylglycerides, 5.38% of FFA and 1.21% of glycerol and after consecutively distillations, monoacylglycerides with 80% of purity was obtained and also oil with 54% of diacylglycerides to be used in human dietary.
Chawla, Mohit
2016-02-16
We report a quantum chemical characterization of the non-natural (synthetic) H-bonded base pair formed by 6-amino-5-nitro-2(1H)-pyridone (Z) and 2-amino-imidazo [1,2-a]-1,3,5-triazin-4(8H)-one (P). The Z:P base pair, orthogonal to the classical G:C base pair, has been introduced in DNA molecules for expanding the genetic code. Our results indicate that the Z:P base pair closely mimics the G:C base pair both in terms of structure and stability. To clarify the role of the NO2 group on the C5 position of the Z base, we compared the stability of the Z:P base pair with that of base pairs having different functional group on the C5 position of Z. Our results indicate that the electron donating/withdrawing properties of the group in the C5 position has a clear impact on the stability of the Z:P base pair, with the strong electron withdrawing nitro group achieving the largest stabilizing effect on the H-bonding interaction, and the strong electron donating NH2 group destabilizing the Z:P pair by almost 4 kcal/mol. Finally, our gas phase and in water calculations confirm that the Z-nitro group reinforce the stacking interaction with its adjacent purine or pyrimidine ring.
Gherardi, Matteo; Puač, Nevena; Marić, Dragana; Stancampiano, Augusto; Malović, Gordana; Colombo, Vittorio; Petrović, Zoran Lj
2015-12-01
Over the past decade the use of ICCD cameras as a means for characterizing non-equilibrium plasmas has been steadily increasing. Due to their high sensitivity and high speed gateability, ICCD cameras enable time-resolved studies of the anatomy and, when adopted in conjunction with filters, monochromators, spectrometers or laser systems, time-resolved investigation of physical and chemical properties of non-equilibrium plasma discharges. This paper is meant as an introduction to ICCD technology and its use as a plasma diagnostic technique, discussing the experimental problems typically associated with its use and providing the readers with practical examples and suggestions on how to address them. In particular, the issues of ICCD camera synchronization with the voltage pulse driving the plasma discharge and of investigating small volume discharges are addressed, focusing mainly on the case of non-equilibrium atmospheric pressure plasma jets. Finally, a possible way to achieve absolute calibration of plasma discharge emission is presented and discussed. A wide range of data, mostly unpublished, is provided here to illustrate the points.
Sarı, Nurşen; Şahin, Songül Çiğdem; Öğütcü, Hatice; Dede, Yavuz; Yalcin, Soydan; Altundaş, Aliye; Doğanay, Kadir
2013-04-01
A new amine containing selenium and their five imine, (SeSchX)(X: -H, F, Cl, Br, CH3), and Ni (II) complexes, [Ni(SeSchX)(H2O)2]Cl/[Ni(SeSchCl)(H2O)Cl], were synthesized. The compounds were characterized by means of elemental analyses, 13C and 1H NMR (for imine), FT-IR, UV-Visible spectroscopy, TGA/DTA and elemental analyses. [Ni(SeSchCl)(H2O)Cl] complex from Ni(II) complexes changes color from yellow to orange in the range pH 5-7. [Ni(SeSchCl)(H2O)Cl] complex has ligand-to-metal charge-transfer (LMCT) transitions in the basic medium. Excitation characteristics and energetic of [Ni(SeSchCl)(H2O)Cl] complex, examined via TD-DFT calculations, reveals transitions of LMCT and π → π* character that matches the experimental values. [Ni(SeSchCl)(H2O)Cl] complex showed the highest antibacterial activity when compared to other complexes reported in this work.
Guo, Jia; Ren, Tiegang; Zhang, Jinglai; Li, Guihui; Li, Weijie; Yang, Lirong
2012-09-01
A series of novel Schiff bases containing pyrazole group were synthesized using 1-aryl-3-methyl-4-benzoyl-5-pyrazolone and phenylenediamine as the starting materials. All as-synthesized Schiff bases were characterized by means of NMR, FT-IR, and MS; and the molecular geometries of two Schiff bases as typical examples were determined by means of single crystal X-ray diffraction. In the meantime, the ultraviolet-visible light absorption spectra and fluorescent spectra of various as-synthesized products were also measured. Moreover, the B3LYP/6-1G(d,p) method was used for the optimization of the ground state geometry of the Schiff bases; and the spectroscopic properties of the products were computed and compared with corresponding experimental data based on cc-pVTZ basis set of TD-B3LYP method. It has been found that all as-synthesized Schiff bases show a remarkable absorption peak in a wavelength range of 270-370 nm; and their maximum emission peaks are around 344 nm and 332 nm, respectively.
Beyazit, Neslihan; Çatıkkaş, Berna; Bayraktar, Şahin; Demetgül, Cahit
2016-09-01
A new tetradentate, unsymmetrical Schiff base ligand (H2L) containing a donor set of N2O2 and its mononuclear Cu(II) and Fe(II) complexes ([CuL] and [FeL]), were synthesized and characterized on the basis of their elemental analysis, FT-IR, Raman, 1H and 13C NMR spectra, electronic and mass spectra, molar conductivity and magnetic susceptibility measurements. Density functional theory (DFT) calculations were performed in order to clarify molecular structures, 1H NMR and 13C NMR chemical shift values, frontier molecular orbitals (FMOs), nonlinear optical properties and map of molecular electrostatic potential (MEP) of the title molecules. In agreement with trials, the results provide a full explanation of the highest efficiency observed for the compounds in relation to the electronic and the structural characteristics. The catecholase-like activity of the complexes toward the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) to the corresponding quinone showed that both complexes have moderate catalytic activity. [FeL] shows higher activity (kcat = 26.4 h-1) than that of [CuL] (kcat = 23.4 h-1).
Ortega, E.; Montecinos, R.; Cattin, L.; Díaz, F. R.; del Valle, M. A.; Bernède, J. C.
2017-08-01
The study of new dipolar A-π-D molecules, which have an acceptor (A) and donor (D) charge joined by a conjugate bridge, have been an attention focus in the recent years due their different properties. In the current work, a molecular system has been modified in order to compare the effect on properties, such as quantum yield. Thus, two series were generated (alkyl- and alkoxy-substituted) to determine if molecules with tertiary asymmetric amines change their optical properties and whether quantum yield is affected. The different products have been characterized by several techniques such as UV-Vis spectrophotometry, elemental analysis, NMR, FT-IR, mass spectroscopy and fluorescence spectroscopy. Furthermore, their behavior in eight organic solvents, dichloromethane, tetrahydrofuran, ethyl acetate, 1,4-dioxane, acetone, acetonitrile, dimethylformamide and dimethylsulfoxide were experimentally and theoretically studied. The quantum yields were higher for the alkyl-substituted series. Theoretically, the dihedral angles formed between the tertiary amine and carbonyl group moieties have a correlation with quantum yield values, helping to explain why they are higher in non-polar solvents. Consequently, the maximum quantum yield was obtained with (E)-2-cyano-3-(5-((E)-2-(9,9-diethyl-7-(methyl(phenyl)amino)-9H-fluoren-2-yl) vinyl)thiophen-2-yl)acrylic acid (M8-1) in 1,4-dioxane, reaching 98.8%.
Chihaoui, Nejla; Hamdi, Besma; Dammak, Thameur; Zouari, Ridha
2016-11-01
This paper gathers the synthesis and study of a novel nonlinear organic-inorganic (1,2-diammoniumcyclohexane tetrabromozincate (II) monohydrate; [C6H10(NH3)2]ZnBr4·H2O) hybrid. The newly developed hybrid was characterized by XRD and spectroscopic (FT-IR, Raman, UV-Visible and CP/MAS-NMR) studies. All theoretical calculations and structural optimization parameters were conducted by using DFT approach with B3LYP/6-31G(d) basis set and the vibrational wavenumbers were evaluated for the affectation of [C6H10(NH3)2]ZnBr4·H2O compound by using transferable scale factor. The inspection of intermolecular links in the studied framework has been executed by the Hirshfeld surface analysis. The nonlinear optical characteristics of this compound were theoretically explored also the molecular orbitals (HOMO) and (LUMO) properties are performed to describe the charge transfer within the crystal.
Duan, Yu-Ai; Geng, Yun; Li, Hai-Bin; Jin, Jun-Ling; Wu, Yong; Su, Zhong-Min
2013-07-15
To seek for high-performance small molecule donor materials used in heterojunction solar cell, six acceptor-donor-acceptor small molecules based on naphtho[2,3-b:6,7-b']dithiophene (NDT) units with different acceptor units were designed and characterized using density functional theory and time-dependent density functional theory. Their geometries, electronic structures, photophysical, and charge transport properties have been scrutinized comparing with the reported donor material NDT(TDPP)2 (TDPP = thiophene-capped diketopyrrolopyrrole). The open circuit voltage (V(oc)), energetic driving force(ΔE(L-L)), and exciton binding energy (E(b)) were also provided to give an elementary understanding on their cell performance. The results reveal that the frontier molecular orbitals of 3-7 match well with the acceptor material PC61 BM, and compounds 3-5 were found to exhibit the comparable performances to 1 and show promising potential in organic solar cells. In particular, comparing with 1, system 7 with naphthobisthiadiazole acceptor unit displays broader absorption spectrum, higher V(oc), lower E(b), and similar carrier mobility. An in-depth insight into the nature of the involved excited states based on transition density matrix and charge density difference indicates that all S1 states are mainly intramolecular charge transfer states with the charge transfer from central NDT unit to bilateral acceptor units, and also imply that the exciton of 7 can be dissociated easily due to its large extent of the charge transfer. In a word, 7 maybe superior to 1 and may act as a promising donor candidate for organic solar cell. Copyright © 2013 Wiley Periodicals, Inc.
Lourenço, A.; Wellock, N.; Thomas, R.; Homer, M.; Bouchard, H.; Kanai, T.; MacDougall, N.; Royle, G.; Palmans, H.
2016-11-01
Water-equivalent plastics are frequently used in dosimetry for experimental simplicity. This work evaluates the water-equivalence of novel water-equivalent plastics specifically designed for light-ion beams, as well as commercially available plastics in a clinical high-energy carbon-ion beam. A plastic- to-water conversion factor {{H}\\text{pl,w}} was established to derive absorbed dose to water in a water phantom from ionization chamber readings performed in a plastic phantom. Three trial plastic materials with varying atomic compositions were produced and experimentally characterized in a high-energy carbon-ion beam. Measurements were performed with a Roos ionization chamber, using a broad un-modulated beam of 11 × 11 cm2, to measure the plastic-to-water conversion factor for the novel materials. The experimental results were compared with Monte Carlo simulations. Commercially available plastics were also simulated for comparison with the plastics tested experimentally, with particular attention to the influence of nuclear interaction cross sections. The measured H\\text{pl,w}\\exp correction increased gradually from 0% at the surface to 0.7% at a depth near the Bragg peak for one of the plastics prepared in this work, while for the other two plastics a maximum correction of 0.8%-1.3% was found. Average differences between experimental and numerical simulations were 0.2%. Monte Carlo results showed that for polyethylene, polystyrene, Rando phantom soft tissue and A-150, the correction increased from 0% to 2.5%-4.0% with depth, while for PMMA it increased to 2%. Water-equivalent plastics such as, Plastic Water, RMI-457, Gammex 457-CTG, WT1 and Virtual Water, gave similar results where maximum corrections were of the order of 2%. Considering the results from Monte Carlo simulations, one of the novel plastics was found to be superior in comparison with the plastic materials currently used in dosimetry, demonstrating that it is feasible to tailor plastic
Jacobson, Leif D; Herbert, John M
2011-12-14
Water cluster anions, (H(2)O)(N)(-), are examined using mixed quantum/classical molecular dynamics based on a one-electron pseudopotential model that incorporates many-body polarization and predicts vertical electron detachment energies (VDEs) with an accuracy of ~0.1 eV. By varying the initial conditions under which the clusters are formed, we are able to identify four distinct isomer types that exhibit different size-dependent VDEs. On the basis of a strong correlation between the electron's radius of gyration and its optical absorption maximum, and extrapolating to the bulk limit (N → ∞), our analysis supports the assignment of the "isomer Ib" data series, observed in photoelectron spectra of very cold clusters, as arising from cavity-bound (H(2)O)(N)(-) cluster isomers. The "isomer I" data reported in warmer experiments are assigned to surface-bound isomers in smaller clusters, transitioning to partially embedded isomers in larger clusters. The partially embedded isomers are characterized by a partially formed solvent cavity at the cluster surface, and they are spectroscopically quite similar to internalized cavity isomers. These assignments are consistent with various experimental data, and our theoretical characterization of these isomers sheds new light on a long-standing assignment problem. © 2011 American Chemical Society
Bruus, Henrik
in complexity, a proper theoretical understanding becomes increasingly important. The basic idea of the book is to provide a self-contained formulation of the theoretical framework of microfluidics, and at the same time give physical motivation and examples from lab-on-a-chip technology. After three chapters...
Estiu, G.; Chacón Villalba, M. E.; Camí, G. E.; Echeverria, G. A.; Soria, D. B.
2014-03-01
Two new complexes of Ni and Zn with 4-chloro-2-nitrobenzenesulfonamide (ClNbsa) have been synthesized and characterized. The structure of the [Ni(ClNbsa)2(NH3)4] complex was determined by X-ray diffraction methods. It crystallizes in the monoclinic P21/c space group with a = 12.8679(3) Å, b = 7.7254(1) Å, c = 12.2478(2) Å, β = 109.899(2)°, V = 1144.85 (4)Å3 and Z = 4 molecules per unit cell. The coordination geometry of the Nickel (II) ion in the complex can be described as a distorted octahedron with two N-sulfonamide and four NH3 groups in opposite vertices. Due to the poor solubility of the Zn(II) complex, their cell parameters were determined by indexing the powder X-ray pattern using the successive dichotomy method implemented in the Fullprof Suite software package. A triclinic cell was determined with cell parameters a = 18.3724(1) Å, b = 7.9468(8) Å, c = 10.2212(9) Å α = 63.061(6) β = 108.754(6) γ = 109.153(6) and V = 1229.97(2)Å3. Nuclear magnetic resonance (NMR) spectroscopy of 1H and 13C have been used for support the structure of the Zn complex. Vibrational and electronic spectroscopy have been used to characterize the compounds, using theoretical calculations for the assignment of the experimental bands. The thermal behavior was investigated by thermogravimetric analyses (TG) and differential thermal analysis (DT).
Pokharia, Mamta; Yadav, Swatantra K.; Mishra, Hirdyesh; Pandey, Nidhi; Tilak, Ragini; Pokharia, Sandeep
2017-09-01
The Schiff base (E)-N3-(2-chlorobenzylidene)-H-1,2,4-triazole-3,5-diamine was synthesised and characterized by FT-IR, Raman, 1H &13C NMR, UV-Vis and mass spectrometry. A density functional theory based quantum chemical calculations were performed at B3LYP/6-311++G(d,p) level of theory. A comparative analysis of calculated vibrational frequencies with experimental vibrational frequencies was carried out and prominent bands were assigned. The theoretical UV-Vis spectral studies were carried out using time dependent-DFT method in gas phase and IEFPCM model with solvent field calculation. Atomic charges at selected atoms were calculated by Mulliken population analyses (MPA), Hirshfeld population analyses (HPA) and Natural population analyses (NPA) schemes. The molecular electrostatic potential (MEP) map was calculated to assign reactive site on the surface of the molecule. The conceptual DFT based global and local reactivity descriptors were calculated to obtain an insight into the structure-activity relationship. For instance, the results indicate that the C11 of compound is more prone to nucleophilic attack as it has found maximum value of electrophilic reactivity descriptors and thus favours the formation of new heterocyclic compounds. The frontier molecular orbital analysis was carried out to study the charge transfer within the molecule. The NBO analysis was performed to get an insight into the intramolecular conjugative electronic interactions. The titled compound was screened for in vitro antimicrobial activity against four bacterial and five fungal strains.
Chen, Liang-Chia; Tapilouw, Abraham Mario
2013-11-01
Stroboscopic white light interferometry (SWLI) has been known as a useful measurement technique for vibrating samples such as micro-electro-mechanical systems (MEMS) or micro-opto-electro-mechanical systems (M(O)EMS) because it enables dynamic mode reconstruction and characterization of the tested system. An approximate model simulation without any experimental confirmation previously indicated that the duty cycle of the light could reduce the accuracy of the measurement. To provide a comprehensive insight into this important phenomenon, the study investigated theoretically and experimentally the effect of duty cycle of the light. An atomic force microscopy cantilever beam vibrating at its second resonant frequency was measured and the experimental measurements were analyzed and compared with the simulated results. In general, a reasonable correspondence between the mathematical model and the experimental measurements has been observed when the duty cycle is less than 15% and the average deviation is kept within 15.4% of the vibration amplitude. However, it is verified that the SWLI using white light LED has its physical detection limits when the cycle time of the strobed light or the light exposure time of the imaging device is more than 20%, in which the maximum measured error can significantly exceed 38.4% of the vibration amplitude.
Koparir, Metin; Orek, Cahit; Koparir, Pelin; Sarac, Kamiran
2013-03-01
This work presents the characterization of 4-ethyl-5-(2-hydroxyphenyl)-2H-1,2,4-triazole-3(4H)-thione (III) by quantum chemical calculations and spectral techniques. The molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C NMR chemical shift values of III in the ground state have been calculated using the density functional method (B3LYP) with the 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure, and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. To determine conformational flexibility, the molecular energy profile of the title compound was obtained by DFT calculations with respect to the selected torsion angle, which was varied from -180° to +180° in steps of 10°. The energetic behavior of III in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). The predicted nonlinear optical properties of III are greater than ones of urea. In addition, DFT calculations of molecular electrostatic potentials and frontier molecular orbitals of III were carried out at the B3LYP/6-31G(d) level of theory. The title compound was screened for antibacterial, antifungal and antioxidant activities.
Oliveira, Carlos Alberto F. de; Silva, Fausthon Fred da; Malvestiti, Ivani [Department of Fundamental Chemistry, UFPE, 50590-470 Recife, PE (Brazil); Malta, Valeria Rodrigues dos S. [Institute of Chemistry and Biotechnology, UFAL, 57062-970 Maceio, AL (Brazil); Dutra, Jose Diogo L.; Costa, Nivan B. da; Freire, Ricardo O. [Department of Chemistry, UFS, 49100-000 Sao Cristovao, SE (Brazil); Junior, Severino A., E-mail: salvesjr@ufpe.br [Department of Fundamental Chemistry, UFPE, 50590-470 Recife, PE (Brazil)
2013-01-15
Two new metal-organic frameworks (MOFs) have been synthesized under different hydrothermal conditions and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and elemental analysis. Compound 1, crystallized in space group P1-bar with the formula [Tm{sub 2}(L){sub 3}(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O, (H{sub 2}L=succinic acid), has triclinic cell parameters of a=7.61780(10), b=10.58050(10), c=12.71030(10), {alpha}=95.3130(10), {beta}=107.4370(10), {gamma}=111.0960(10) and a cell volume of 888.446(16) A{sup 3}. Compound 2, crystallized in space group I2/a with the same formula, is monoclinic, with cell parameters of a=13.77020(10), b=7.63170(10), c=17.2410(2), {beta}=101.303(10) and a cell volume of 1776.72(3) A{sup 3}. The results of this work indicate that a flexible succinate ligand that provides several modes of coordination can lead to different conformations, depending on the temperature used in the reaction. In the theoretical part of this study, semiempirical quantum chemistry methods using AM1, PM3 and PM6 models are employed to predict the structure of MOFs, calculate the geometric and crystallographic parameters, and make comparisons with experimental data. - Graphical abstract: Scheme of obtaining [Tm{sub 2}(C{sub 4}H{sub 4}O{sub 4}){sub 3}(H{sub 2}O){sub 2}]H{sub 2}O in two different crystalline phases under the influence of reaction temperature. Highlights: Black-Right-Pointing-Pointer Was synthesized new MOFs based on Tm{sup 3+} ions and succinic acid in different temperature. Black-Right-Pointing-Pointer The change in the temperature leads to two compounds with different crystalline systems. Black-Right-Pointing-Pointer The Sparkle AM1, PM3 and PM6 models were used to comparison of the theoretical and experimental cell.
Marc Vanderhaeghen
2007-04-01
The theoretical issues in the interpretation of the precision measurements of the nucleon-to-Delta transition by means of electromagnetic probes are highlighted. The results of these measurements are confronted with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice QCD, large-Nc relations, perturbative QCD, and QCD-inspired models. The link of the nucleon-to-Delta form factors to generalized parton distributions (GPDs) is also discussed.
Zahedifar, Mahboobeh; Razavi, Razieh; Sheibani, Hassan
2016-12-01
New 7-hydroxy-6-phenyl-3-(phenyldiazenyl)pyrazolo[1,5-a]pyrimidine-2,5(1H,4H)-dione derivatives were synthesized from the reaction of (chlorocarbonyl)phenyl ketene and 5-amino pyrazolones in high to excellent yields and short reaction times. Structures of the new compounds were fully characterized by their spectral data IR, 1H NMR, and 13C NMR and by the theoretical results. Density Functional Theory (DFT) was used to optimize the structures, compute the energies and vibrational frequencies IR and 1H NMR shielding tensors of the desired products. The theoretical results excellent are compared with the experimental data.
Mikeš, Daniel
2010-05-01
Theoretical geology Present day geology is mostly empirical of nature. I claim that geology is by nature complex and that the empirical approach is bound to fail. Let's consider the input to be the set of ambient conditions and the output to be the sedimentary rock record. I claim that the output can only be deduced from the input if the relation from input to output be known. The fundamental question is therefore the following: Can one predict the output from the input or can one predict the behaviour of a sedimentary system? If one can, than the empirical/deductive method has changes, if one can't than that method is bound to fail. The fundamental problem to solve is therefore the following: How to predict the behaviour of a sedimentary system? It is interesting to observe that this question is never asked and many a study is conducted by the empirical/deductive method; it seems that the empirical method has been accepted as being appropriate without question. It is, however, easy to argument that a sedimentary system is by nature complex and that several input parameters vary at the same time and that they can create similar output in the rock record. It follows trivially from these first principles that in such a case the deductive solution cannot be unique. At the same time several geological methods depart precisely from the assumption, that one particular variable is the dictator/driver and that the others are constant, even though the data do not support such an assumption. The method of "sequence stratigraphy" is a typical example of such a dogma. It can be easily argued that all the interpretation resulting from a method that is built on uncertain or wrong assumptions is erroneous. Still, this method has survived for many years, nonwithstanding all the critics it has received. This is just one example of the present day geological world and is not unique. Even the alternative methods criticising sequence stratigraphy actually depart from the same
Joos, Georg
1986-01-01
Among the finest, most comprehensive treatments of theoretical physics ever written, this classic volume comprises a superb introduction to the main branches of the discipline and offers solid grounding for further research in a variety of fields. Students will find no better one-volume coverage of so many essential topics; moreover, since its first publication, the book has been substantially revised and updated with additional material on Bessel functions, spherical harmonics, superconductivity, elastomers, and other subjects.The first four chapters review mathematical topics needed by theo
Al-Jaroudi, Said S; Altaf, Muhammad; Al-Saadi, Abdulaziz A; Kawde, Abdel-Nasser; Altuwaijri, Saleh; Ahmad, Saeed; Isab, Anvarhusein A
2015-10-01
The gold(III) complexes of the type (1,2-diaminocyclohexane)(1,3-diaminopropane)gold(III) chloride, [(DACH)Au(pn)]Cl3, [where DACH = cis-, trans-1,2- and S,S-1,2-diaminocyclohexane and pn = 1,3-diaminopropane] have been synthesized and characterized using various spectroscopic and analytical techniques including elemental analysis, UV-Vis and FTIR spectroscopy; solution as well as solid-state NMR measurements. The solid-state (13)C NMR shows that 1,2-diaminocyclohexane (1,2-DACH) and 1,3-diaminopropane (pn) are strongly bound to the gold(III) center via N donor atoms. The stability of the mixed diamine ligand gold(III) was checked by UV-Vis spectroscopy and NMR measurements. The molecular structure of compound 1 (containing cis-1,2-DACH) was determined by X-ray diffraction analysis. The structure of 1 consists of [(cis-DACH)Au(pn)](3+) complex ion and chloride counter ions. Each gold atom in the complex ion adopts a distorted square-planar geometry. The structural details and relative stabilities of the four possible isomers of the complexes were also estimated at the B3LYP/LANL2DZ level of theoretical calculations. The computational study demonstrates that trans- conformations are slightly more stable than the cis- conformations. The antiproliferative effects and cytotoxic properties of the mixed ligand gold(III) complexes were evaluated in vitro on human gastric SGC7901 and prostate PC3 cancer cells using MTT assay. The antiproliferative study of the gold(III) complexes on PC3 and SGC7901 cells indicate that complex 3 (containing 1S,2S-(+)-1,2-(DACH)) is the most effective antiproliferative agent. The IC50 data reveal that the in vitro cytotoxicity of complex 3 against SGC7901 cancer cells manifested similar and very pronounced cytotoxic effects with respect to cisplatin. Moreover, the electrochemical behavior, and the interaction of complex 3 with two well-known model proteins, namely, hen egg white lysozyme and bovine serum albumin is also reported.
Stöltzner, Michael
Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.
Theoretical Physics 1. Theoretical Mechanics
Dreizler, Reiner M.; Luedde, Cora S. [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik
2010-07-01
After an introduction to basic concepts of mechanics more advanced topics build the major part of this book. Interspersed is a discussion of selected problems of motion. This is followed by a concise treatment of the Lagrangian and the Hamiltonian formulation of mechanics, as well as a brief excursion on chaotic motion. The last chapter deals with applications of the Lagrangian formulation to specific systems (coupled oscillators, rotating coordinate systems, rigid bodies). The level of this textbook is advanced undergraduate. The authors combine teaching experience of more than 40 years in all fields of Theoretical Physics and related mathematical disciplines and thorough knowledge in creating advanced eLearning content. The text is accompanied by an extensive collection of online material, in which the possibilities of the electronic medium are fully exploited, e.g. in the form of applets, 2D- and 3D-animations. (orig.)
Barney G. Glaser, Ph.D., Hon. Ph.D.
2009-11-01
Full Text Available Theoretical sorting has brought the analyst to the point of pent-up pressure to write: to see the months of work actualized in a “piece.” But this is only a personal pressure. The goal of grounded theory methodology, above all is to offer the results to the public, usually through one or more publications. We will focus on writing for publication, which is the most frequent way that the analyst can tell how people are “buying” what really matters in sociology, or in other fields.Both feedback on and use of publications will be the best evaluation of the analyst’s grounded theory. It will be his main source or criticism, constructive critique, and frequently of career rewards. In any case, he has to write to expand his audience beyond the limited number of close colleagues and students. Unless there is a publication, his work will be relegated to limited discussion, classroom presentation, or even private fantasy. The rigor and value of grounded theory work deserves publication. And many analysts have a stake in effecting wider publics, which makes their substantive grounded theory count.
Borkowski Andrzej
2015-12-01
Full Text Available The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+ that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis.
Borkowski, Andrzej; Kosek, Wiesław
2015-12-01
The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+) that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis. New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2nd, 3rd and 4th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands.
Vanko, Gyoergy; Bordage, Amelie; Pápai, Mátyás Imre
2015-01-01
Theoretical predictions show that depending on the populations of the Fe 3d(xy), 3d(xz), and 3d(yz) orbitals two possible quintet states can exist for the high-spin state of the photoswitchable model system [Fe(terpy)(2)](2+). The differences in the structure and molecular properties of these B-5...
Theoretical Mechanics Theoretical Physics 1
Dreizler, Reiner M
2011-01-01
After an introduction to basic concepts of mechanics more advanced topics build the major part of this book. Interspersed is a discussion of selected problems of motion. This is followed by a concise treatment of the Lagrangian and the Hamiltonian formulation of mechanics, as well as a brief excursion on chaotic motion. The last chapter deals with applications of the Lagrangian formulation to specific systems (coupled oscillators, rotating coordinate systems, rigid bodies). The level of this textbook is advanced undergraduate. The authors combine teaching experience of more than 40 years in all fields of Theoretical Physics and related mathematical disciplines and thorough knowledge in creating advanced eLearning content. The text is accompanied by an extensive collection of online material, in which the possibilities of the electronic medium are fully exploited, e.g. in the form of applets, 2D- and 3D-animations. - A collection of 74 problems with detailed step-by-step guidance towards the solutions. - A col...
Romanowski,Stela Maris de M.; Sérgio de P. Machado; Friedermann,Geraldo R.; Antonio S Mangrich; Hermann,Monique de F.; Lima,Hugo Orofino; Nakagaki,Shirley
2010-01-01
The synthesis and characterization of the manganese(II) complexes [MnII(Hbpeten)] and [MnII(Hbnbpeten)], where H3bpeten and H3bnbpeten are respectively [N,N'-bis-(2-hydroxybenzyl)-N-(2-pyridylmethyl)-N'-(2-hydroxyethyl)ethane-1,2-diamine] and [N,N'-bis-(5-nitro-2-hydroxybenzyl)-N'-(2-hydroxyethyl)ethane-1,2-diamine], are reported. The characterization was carried out by elemental analyses, cyclic voltammetry, spectroscopic methods (UV-Vis, FTIR, ¹H NMR), electronic paramagnetic resonance spec...
Honda, Masaki; Kudo, Tatsuya; Kuwa, Takahiro; Higashiura, Takuma; Fukaya, Tetsuya; Inoue, Yoshinori; Kitamura, Chitoshi; Takehara, Munenori
2017-02-01
Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13'Z)-, (5Z,13Z,9'Z)-, (9Z,9'Z)-, (5Z,13'Z)-, (5Z,9'Z)-, (5Z,9Z,5'Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations.
Sharma, Sakshi; Brahmachari, Goutam; Banerjee, Bubun; Nurjamal, Khondekar; Kumar, Abhishek; Srivastava, Ambrish Kumar; Misra, Neeraj; Pandey, Sarvesh Kumar; Rajnikant; Gupta, Vivek K.
2016-08-01
The present communication deals with the eco-friendly synthesis, spectral properties and X-ray crystal structure of an indole derivative - Ethyl 2'-amino-3'-cyano-6'-methyl-5-nitro-2-oxospiro [indoline-3,4'-pyran]-5'-carboxylate. The title compound was synthesized in 87% yield. The crystal structure of the molecule is stabilized by intermolecular Nsbnd H … N, Nsbnd H … O and Csbnd H … π interactions. The molecule is organized in the crystal lattice forming sheet like structure. To interpret the experimental data, ab initio computations of the vibrational frequencies were carried out using the Gaussian 09 program followed by the full optimizations done using Density Functional Theory (DFT) at B3LYP/6-31 + G(d,p) level. The combined use of experiments and computations allowed a firm assignment of the majority of observed bands for the compound. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) with frontier orbital gap were presented. The electronic and charge transfer properties have been explained on the basis of highest occupied molecular orbitals (HOMOs), lowest unoccupied molecular orbitals (LUMOs) and density of states (DOS). From the optimized geometry of the molecule, molecular electrostatic potential (MEP) distribution, frontier molecular orbitals (FMOs) of the title compound have been calculated in the ground state theoretically. The theoretical results showed good agreement with the experimental values. First hyperpolarizability values have been calculated to describe the nonlinear optical (NLO) property of the synthesized compound.
Özdemir, Namık; Dayan, Osman; Yavaşoğlu, Melek Tercan; Çetinkaya, Bekir
2014-10-01
The title molecular salt (2), 2,2";-(pyridine-2,6-diyl)bis(1H-benzo[d]imidazol-3-ium) 2,4,6-trimethylbenzenesulfonate chloride (C19H15N52+·C9H11O3S-·Cl-), was synthesized unexpectedly from the reaction of 2,6-bis(benzimidazol-2-yl)pyridine (1) with 2-mesitylenesulfonyl chloride. Spectroscopic techniques (FT-IR, NMR and UV-vis.) were used to characterize compounds 1 and 2. Solid-state structure of compound 2 was identified by X-ray crystallography. Theoretical characterization of the spectroscopic properties of compounds 1 and 2 was achieved using the density functional theory (DFT) method with the 6-311G(d,p) basis set, and the results were checked against the experimental data. Electronic absorption spectra of the compounds have also been obtained.
Yıldırım, İlkay [Department of Radiotherapy, Vocational School of Health Services, Biruni University, Topkapı, 34010 Istanbul (Turkey); Çelik, Yunus [Department of Physics, Faculty of Arts and Science, Ondokuz Mayıs University, Atakum, 55139 Samsun (Turkey); Karabulut, Bünyamin, E-mail: bbulut@omu.edu.tr [Department of Computer Engineering, Faculty of Engineering, Ondokuz Mayıs University, Atakum, 55139 Samsun (Turkey)
2016-02-15
In this study, the paramagnetism in bis(hydrogeno pyridine-2,6-dicarboxylato) nickel(II) trihydrate, [Ni(Hdpc){sub 2}]·3H{sub 2}O, has been investigated after doping the sample with Cu{sup 2+} ions. The g and hyperfine parameters were obtained by electron paramagnetic resonance (EPR) experiments performed at ambient temperature. The study shows that Cu{sup 2+} ion defects the structure and exists interstitially in the lattice having a distorted local environment. It also shows the existence of two magnetically inequivalent Cu{sup 2+} sites. Experimental values for both EPR and optical spectrum studies were verified by using the appropriate theoretical approaches.
Soleimani Amiri, Somayeh; Makarem, Somayeh; Ahmar, Hamid; Ashenagar, Samaneh
2016-09-01
The structural, electronic, and spectroscopic properties of 4-methyl-5-((5-phenyl-1,3,4 oxadiazol-2-yl)thio)benzene-1,2-diol (MPOTB) have been carried out at ab initio and DFT levels. A detailed study of geometrical parameters, Infrared spectrum, chemical shifts (13C NMR, 1H NMR), and electronic properties of the title compound is presented. The correlation between the theoretical and the experimental 13C, and 1H chemical shifts of MPOTB were about 1.02-1.03 and 0.98-1.00, respectively. The electronic properties, such as molecular electrostatic potential, NBO atomic charges, HOMO and LUMO energies were performed at above levels. Rather high hardness of MPOTB introduces it as a stable molecule. As a result, the calculated findings were compared with the observed values and generally found to be in good agreement.
Tong, Yujin, E-mail: tong@fhi-berlin.mpg.de; Kirsch, Harald; Wolf, Martin; Campen, R. Kramer, E-mail: campen@fhi-berlin.mpg.de [Fritz Haber Institute of the Max Planck Society, 14195 Berlin (Germany); Wirth, Jonas; Saalfrank, Peter [Institute of Chemistry, University of Potsdam, 14476 Potsdam OT Golm (Germany)
2015-02-07
Oxide/water interfaces are ubiquitous in a wide variety of applications and the environment. Despite this ubiquity, and attendant decades of study, gaining molecular level insight into water/oxide interaction has proven challenging. In part, this challenge springs from a lack of tools to concurrently characterize changes in surface structure (i.e., water/oxide interaction from the perspective of the solid) and O—H population and local environment (i.e., water/oxide interaction from the water perspective). Here, we demonstrate the application of surface specific vibrational spectroscopy to the characterization of the interaction of the paradigmatic α-Al{sub 2}O{sub 3}(0001) surface and water. By probing both the interfacial Al—O (surface phonon) and O—H spectral response, we characterize this interaction from both perspectives. Through electronic structure calculation, we assign the interfacial Al—O response and rationalize its changes on surface dehydroxylation and reconstruction. Because our technique is all-optical and interface specific, it is equally applicable to oxide surfaces in vacuum, ambient atmospheres and at the solid/liquid interface. Application of this approach to additional alumina surfaces and other oxides thus seems likely to significantly expand our understanding of how water meets oxide surfaces and thus the wide variety of phenomena this interaction controls.
Marques, Lippy F. [Instituto de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro 20550-013 (Brazil); Correa, Charlane C. [Departamento de Química-ICE, Universidade Federal de Juiz de Fora, Juiz de Fora-MG, 36036-330 (Brazil); Ribeiro, Sidney J.L.; Santos, Molíria V. dos [Institute of Chemistry, São Paulo State University − UNESP, CP 355 Araraquara-SP 14801-970 Brazil (Brazil); Dutra, José Diogo L.; Freire, Ricardo O. [Pople Computational Chemistry Laboratory, Departamento de Química, Universidade Federal de Sergipe, São Cristóvão-SE 49100-000 (Brazil); Machado, Flávia C., E-mail: flavia.machado@ufjf.edu.br [Departamento de Química-ICE, Universidade Federal de Juiz de Fora, Juiz de Fora-MG, 36036-330 (Brazil)
2015-07-15
In this paper, the synthesis of three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. Crystal structure of (1) reveals that each lanthanide ion is seven-coordinated by oxygen atoms in an overall distorted capped trigonal – prismatic geometry. The 2,5-tdc{sup 2−} ligands connect four Ln(III) centers, adopting (κ{sup 1}–κ{sup 1})–(κ{sup 1}–κ{sup 1})–μ{sub 4} coordination mode, generating an 8-connected uninodal 3D network. In addition, theoretical studies for Eu(III) complex were performed using the Sparkle model for lanthanide complexes. - Graphical abstract: Three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), were synthesized and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. - Highlights: • Three new LnMOFs were synthesized and fully characterized. • Ho{sup 3+}, Gd{sup 3+} and Eu{sup 3+} complexes photoluminescence properties were investigated. • Theoretical approaches for Eu{sup 3+} complex luminescence has been performed. • An energy level diagram is used to establish the ligand-to-metal energy transfer. • These metal−organic frameworks can act as light conversion molecular devices.
Sonia, Ayyavoo Sait; Bhaskaran, Ramalingam
2017-04-01
New homoleptic complexes of the form [Co(L1)3] & [Co(L2)3] where L1 = (ethylaminoethanol dithiocarbamate) 1 and L2 = (methylaminoethanol dithiocarbamate) 2 have been prepared and characterized by elemental analysis, IR, UV-visible absorption spectra, Cyclic voltammetry,1H and C13 NMR. The thermal properties were studied using a simultaneous thermal analyzer, and showed two main steps of decomposition. In addition, structures for 1 and 2 have been elucidated by X-ray crystallography. The single-crystal X-ray analysis for both the complexes showed distorted octahedral geometry. The optimized molecular structure, natural bond orbital analysis, electrostatic potential map, HOMO-LUMO energies, molecular properties, and atomic charges of these molecules have been studied by performing DFT/B3LYP/6-31G(d,p) level of theory in gas phase.
Aktan, Ebru; Gündüzalp, Ayla Balaban; Özmen, Ümmühan Özdemir
2017-01-01
The carboxamides; N,N‧-bis(thiophene-2-carboxamido)-1,3-diaminopropanol (L1) and N,N‧-bis(furan-2-carboxamido)-1,3-diaminopropanol (L2) were synthesized and characterized using 1H NMR, 13C NMR, LC-MS and FT-IR spectrum. The molecular geometries of these molecules were optimized by DFT/B3LYP method with 6-311G(d,p) basis set in Gaussian 09 software. The geometrical parameters, frontier molecular orbitals (FMOs) and molecular electrostatic potential (MEP) mapped surfaces were calculated by the same basis set. Dinuclear Cu(II) and Zn(II) complexes having general formula as [MLCl]2Cl2.nH2O (in which M = Cu(II),Zn(II); n = 0,2) were also synthesized and characterized using LC-MS and FT-IR spectrum, thermogravimetric analysis (TGA/DTA curves), magnetic moments and molar conductivities. Coordination was found to be through carbonyl oxygen and two chlorine atoms as bridging in distorted tetrahedral geometry. The optimized structures, geometrical parameters, frontier molecular orbitals (FMOs) and dipole moments of metal complexes were also obtained by DFT/B3LYP method with LanL2DZ basis set. Antibacterial activities of the compounds were screened against E. coli using microdilution method (MIC's in μg/mL). The activity results show that the corresponding compounds exhibit good to moderate antibacterial effects when compared with sulfamethoxazole and sulfisoxazole antibiotics as positive controls. Also, metal complexes have remarkable increase in their activities than parent ligands against E. coli which is mostly effected by [Cu(L2)Cl]2Cl2 complex as potential antibacterial agent.
Li, Kang; Tang, Guodong; Kou, ShanShan; Culnane, Lance F.; Zhang, Yu; Song, Yinglin; Li, Rongqing; Wei, Changmei
2015-03-01
Three complexes of M(DPIP)2 (M = Cu, Co, Zn as 1, 2, 3) were synthesized and characterized by elemental analysis, IR, UV-Vis, thermogravimetry, and X-ray diffraction. Their nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 70% for complex 1 (45 μJ pulse), and 93% for complex 3 (68 μJ pulse at the focus point). The nonlinear absorption coefficient, β, is 1.4 × 10-11 m/W for 1 and 5.6 × 10-13 m/W for 3, and the third-order nonlinear refraction index, n2, is 1.0 × 10-18 m2/W for 3. Complex 1 shows self-defocusing property, while complex 3 exhibits self-focusing property. The thermogravimetric results show that the frame structure of compounds 1-3 begin to collapse at 400, 250 and 280 °C, respectively, which suggests that they elicit excellent thermal stability. This research aims to provide better understanding of these compounds, and offer preliminary explanations for the significant differences between compounds 1-3, in order to potentially help in the designing of future novel materials with NLO properties.
Serbest, Kerim; Karaoğlu, Kaan; Erman, Murat; Er, Mustafa; Değirmencioğlu, Ismail
2010-10-15
Tetra((1-hydroxyiminomethylnaphthalen-2-yloxy)methyl)ethene (THIMNYOME), H(4)L, was synthesized by the agents of 2-hydroxy-1-naphtaldehyde, tetra(bromomethyl)ethene and hydroxylamine hydrochloride in two steps. Characterization of THIMNYOME and its dinuclear complexes was made by elemental analyses, IR, (1)H- and (13)C NMR, UV-vis, electrospray ionisation mass spectra, molar conductivities and magnetic susceptibility measurements. In the light of these results, it was suggested that the ligand coordinate to each metal atom by the two ether oxygen, two nitrogen atoms of oxime imine (CN) and an axial oxygen of perchlorate to form pseudo square-pyramidal complexes with Ni(II), Cu(II) and Zn(II). Molar conductivity measurements reveal that all the complexes are non-electrolytes. In addition, the full geometric optimization of the tetraoxime ligand (4) has been made by the B3LYP/6-31G(d) level in order to establish a stable conformation. Additionally, all the complex structures have been studied in the B3LYP/LANL2DZ level. NBO charge distribution and the characteristics of frontier molecular orbitals of these complexes have also been investigated in order to see the electrons movement between ligand and metal atom in the same level.
Shafaatian, Bita; Mousavi, S. Sedighe; Afshari, Sadegh
2016-11-01
New dimer complexes of zinc(II), copper(II) and nickel(II) were synthesized using the Schiff base ligand which was formed by the condensation of 2-aminothiophenol and 2-hydroxy-5-methyl benzaldehyde. This tridentate Schiff base ligand was coordinated to the metal ions through the NSO donor atoms. In order to prevent the oxidation of the thiole group during the formation of Schiff base and its complexes, all of the reactions were carried out under an inert atmosphere of argon. The X-ray structure of the Schiff base ligand showed that in the crystalline form the SH groups were oxidized to produce a disulfide Schiff base as a new double Schiff base ligand. The molar conductivity values of the complexes in dichloromethane implied the presence of non-electrolyte species. The fluorescence properties of the Schiff base ligand and its complexes were also studied in dichloromethane. The products were characterized by FT-IR, 1H NMR, UV/Vis spectroscopies, elemental analysis, and conductometry. The crystal structure of the double Schiff base was determined by single crystal X-ray diffraction. Furthermore, the density functional theory (DFT) calculations were performed at the B3LYP/6-31G(d,p) level of theory for the determination of the optimized structures of Schiff base complexes.
Özdemir, Namık
2012-06-01
The title molecular salt, 2-mesityl-1H-benzo[d]imidazol-3-ium chloride (C(16)H(17)N(2)(+)·Cl-), was synthesized unexpectedly from the reaction of N-[(1E)-mesitylmethylene]benzene-1,2-diamine and CoCl(2)·6H(2)O, and characterized by elemental analysis, (1)H NMR and FT-IR spectroscopies, and single-crystal X-ray diffraction technique. In addition, quantum chemical calculations employing density functional theory (DFT) method with the 6-311++G(d,p) basis set were performed to study the molecular, spectroscopic and some electronic structure properties of the title compound, and the results were compared with the experimental findings. The computational result shows that the optimized geometry can well reproduce the crystal structural parameters. The intermolecular proton transfer process between the ionic (C(16)H(17)N(2)(+)·Cl-) and nonionic forms (C(16)H(16)N(2)·HCl) of the title salt is investigated and found to be almost barierless with an energy value of 0.20 kcal mol(-1). The NLO properties of the compound are bigger than those of urea. Copyright © 2012 Elsevier B.V. All rights reserved.
Senthilkumar, Kabali; Thirumoorthy, Krishnan; Vinitha, G.; Soni, Kiran; Bhuvanesh, Nattamai S. P.; Palanisami, Nallasamy
2017-01-01
The d10 metal complexes based on 3-methyl-5-ferrocenyl-1H-pyrazole (L = 3-Me-5-FcPz) ligand [M(L)4(NO3)2] Zn=(1) and Cd=(2), [Hg(L)4(NO3)2].dmf (3) have been synthesized and characterized by FT-IR, NMR, UV-Vis and elemental analysis. The molecular structure of compound 2 and its crystal packing were determined by single crystal X-ray diffraction. The nitrate anions are also involved in intermolecular hydrogen bonding with adjacent ferrocene units and it forms zig-zag one-dimensional polymeric structure. UV-Vis investigations on the positive solvatochromic behavior of 1-3 revealed that the solvation of the push-pull character increases with increasing polarity. The third-order nonlinear optical (NLO) properties of 1-3 have been determined by Z-scan technique and the results indicate that compounds 1-3 exhibits the strong self-defocusing effect. The nonlinear susceptibility χ(3) values are calculated in the order of 10-6 esu.
Ilhan, Salih; Baykara, Haci; Oztomsuk, Abdussamet; Okumus, Veysi; Levent, Abdulkadir; Salih Seyitoglu, M.; Ozdemir, Sadin
2014-01-01
A new Schiff base ligand was synthesized by reaction of 5-bromosalicylaldehyde with 1,2-bis(4-chloro-2-aminophenoxy)ethane. Then the Schiff base complexes were synthesized by the reaction of metal salts and the novel Schiff base. The molar conductivity properties of the complexes were studied and found out that the complexes are nonelectrolytes. The structures of the ligand and its metal complexes were characterized by elemental analysis, FT-IR, UV-VIS, magnetic susceptibility measurements, molar conductivity measurements, and thermal gravimetric analysis. In addition antioxidant, theoretical NMR studies and cyclic voltammetry of the complexes were done. Two methods namely metal chelating activity and diphenylpicrylhydrazyl (DPPH) radical scavenging method were used to determine the antioxidant activity, and antibacterial properties of the compounds were also studied.
Dewi, Dina Silvia; Osaigbovo Enomayo, Augustine; Mohsin, Rizwan; Karmakar, Shyamal; Ghergut, Julia; Sauter, Martin
2016-04-01
Flow-storage repartition (FSR) analysis (Shook 2003) is a versatile tool for characterizing subsurface flow and transport systems. FSR can be derived from measured signals of inter-well tracer tests, if certain requirements are met - basically, the same as required for equivalence between fluid residence time distribution (RTD) and a measured inter-well tracer signal (pre-processed and de-convolved if necessary). Nominally, a FSR is derived from a RTD as a trajectory in normalized {1st, 0th}-order statistical moment space; more intuitively, as a parametric plot of 0th-order against 1st-order statistical moments of RTD truncated at time t, with t as a parameter running from the first tracer input to the latest available tracer sampling; 0th-order moments being normalized by the total tracer recovery, and 1st-order moments by the mean RT. Fracture-dominated systems plot in the upper left (high F , low S) region of FSR diagrams; a homogeneous single-continuum with no dispersion (infinite Peclet number) displays a straight line from {F ,S}={0,0} to {F ,S}={1,1}. This analysis tool appears particularly attractive for characterizing markedly-heterogeneous, porous-fissured-fractured (partly karstified) formations like those targeted by geothermal exploration in the Malm-Molasse basin in Southern Germany, and especially for quantifying flow and transport contributions from contrasting facies types ('reef' versus 'bedded'). However, tracer tests conducted in such systems with inter-well distances of some hundreds of metres (as required by economic considerations on geothermal reservoir sizing) face the problem of very long residence times - and thus the need to deal with incomplete (truncated) signals. For the geothermal well triplet at the Sauerlach site near Munich, tracer peak arrival times exceeding 2 years have been predicted, and signal tails decreasing by less than 50% over >10 years, which puts great uncertainty on the (extrapolation-based) normalizing factors
Ni, Haiwei; Zhang, Yu; Zhang, Fang; Zhao, Jianying; Wu, Liubi; Chu, Xiaozhong
2015-03-05
3-(2,6-Dichlorobenzyl)-5-methyl-N-nitro-1,3,5-oxadiazinan-4-imine (DNOI) was synthesized and characterized by X-ray diffraction, FT-IR, FT-Raman and UV-Vis spectra. The X-ray diffraction study showed that DNOI has a one dimensional configuration, due to the intermolecular C9H⋯O1 and N4H⋯O2 hydrogen bonds. The benzene ring and the oxadiazine rings are tilted with respect to each other by 63.07° (C3N1C5C6). Vibrational spectra and electronic spectra measurements were made for the compound. Optimized geometrical structure and harmonic vibrational frequencies were computed with DFT (B3LYP, B3P86, and M062X) methods using 6-311++G(d,p) basis set. Assignments of the observed spectra were proposed. The equilibrium geometries computed by all of the methods were compared with X-ray diffraction results. The absorption spectra of the title compound were computed both in gas phase and in CH3OH solution using TD-B3LYP/6-311++G(d,p) and PCM-B3LYP/6-311++G(d,p) approaches, respectively. The calculated results provide a good description of positions of the bands maxima in the observed electronic spectrum. Temperature dependence of thermodynamic parameters in the range of 100-1000K were determined, entropy, heat capacity and enthalpy changes were increasing with temperature increasing, while for Gibbs free energy is decreasing with temperature increasing. The bond orbital occupancies, contribution from parent natural bond orbital (NBO), the natural atomic hybrids was calculated and discussed. Copyright © 2014 Elsevier B.V. All rights reserved.
Tamer, Ömer; Avcı, Davut; Atalay, Yusuf; Çoşut, Bünyemin; Zorlu, Yunus; Erkovan, Mustafa; Yerli, Yusuf
2015-11-01
The triaqua(1,10-phenanthroline-2,9-dicarboxylato)manganese(II) dihydrate complex was prepared and its crystal structure was determined by using single crystal X-ray diffraction. Its structure was also characterized by the applying of FT-IR, Raman and UV-vis spectroscopies. The manganese(II) ion was located to center of distorted pentagonal-bipyramidal geometry. Electron paramagnetic resonance (EPR) measurement was carried out on the Mn(II) complex. In order to support experimental results, density functional theory calculations were performed at HSEH1PBE level and LanL2DZ basis set. Obtained results indicated that theoretical results can replace the experimental ones. The relatively active ν(CO) ν(CC) and ν(CN) stretching vibration peaks appeared in IR and Raman spectra of complex 1 which are indicators of charge transfer within complex 1 suggest that complex 1 is a good candidate for nonlinear optical materials. The HOMO and LUMO energies determined that complex 1 is stable and the charge transfer occurs within complex 1.
Blatt, John M
2010-01-01
A classic work by two leading physicists and scientific educators endures as an uncommonly clear and cogent investigation and correlation of key aspects of theoretical nuclear physics. It is probably the most widely adopted book on the subject. The authors approach the subject as ""the theoretical concepts, methods, and considerations which have been devised in order to interpret the experimental material and to advance our ability to predict and control nuclear phenomena.""The present volume does not pretend to cover all aspects of theoretical nuclear physics. Its coverage is restricted to
2002-01-01
The proceedings contains 8 papers from the Conference on Theoretical Computer Science. Topics discussed include: query by committee, linear separation and random walks; hardness results for neural network approximation problems; a geometric approach to leveraging weak learners; mind change...
Order-theoretical connectivity
T. A. Richmond
1990-01-01
Full Text Available Order-theoretically connected posets are introduced and applied to create the notion of T-connectivity in ordered topological spaces. As special cases T-connectivity contains classical connectivity, order-connectivity, and link-connectivity.
2002-01-01
The proceedings contains 8 papers from the Conference on Theoretical Computer Science. Topics discussed include: query by committee, linear separation and random walks; hardness results for neural network approximation problems; a geometric approach to leveraging weak learners; mind change...
Consensus theoretic classification methods
Benediktsson, Jon A.; Swain, Philip H.
1992-01-01
Consensus theory is adopted as a means of classifying geographic data from multiple sources. The foundations and usefulness of different consensus theoretic methods are discussed in conjunction with pattern recognition. Weight selections for different data sources are considered and modeling of non-Gaussian data is investigated. The application of consensus theory in pattern recognition is tested on two data sets: 1) multisource remote sensing and geographic data and 2) very-high-dimensional remote sensing data. The results obtained using consensus theoretic methods are found to compare favorably with those obtained using well-known pattern recognition methods. The consensus theoretic methods can be applied in cases where the Gaussian maximum likelihood method cannot. Also, the consensus theoretic methods are computationally less demanding than the Gaussian maximum likelihood method and provide a means for weighting data sources differently.
Theoretical and computational chemistry.
Meuwly, Markus
2010-01-01
Computer-based and theoretical approaches to chemical problems can provide atomistic understanding of complex processes at the molecular level. Examples ranging from rates of ligand-binding reactions in proteins to structural and energetic investigations of diastereomers relevant to organo-catalysis are discussed in the following. They highlight the range of application of theoretical and computational methods to current questions in chemical research.
Theoretical physics and astrophysics
Ginzburg, VL
1979-01-01
The aim of this book is to present, on the one hand various topics in theoretical physics in depth - especially topics related to electrodynamics - and on the other hand to show how these topics find applications in various aspects of astrophysics. The first text on theoretical physics and astrophysical applications, it covers many recent advances including those in X-ray, &ggr;-ray and radio-astronomy, with comprehensive coverage of the literature
Liu, Wenjing; Christian, Jonathan H; Al-Oweini, Rami; Bassil, Bassem S; van Tol, Johan; Atanasov, Mihail; Neese, Frank; Dalal, Naresh S; Kortz, Ulrich
2014-09-02
Two monochromium(III)-containing heteropolytungstates, [Cr(III)(HP(V)W7O28)2](13-) (1a) and [Cr(III)(HAs(V)W7O28)2](13-) (2a), were prepared via simple, one-pot reactions in aqueous, basic medium, by reaction of the composing elements, and then isolated as hydrated sodium salts, Na13[Cr(III)(HP(V)W7O28)2]·47H2O (1) and Na13[Cr(III)(HAs(V)W7O28)2]·52H2O (2). Polyanions 1a and 2a comprise an octahedrally coordinated Cr(III) ion, sandwiched by two {PW7} or {AsW7} units. Both compounds 1 and 2 were fully characterized in the solid state by single-crystal XRD, IR spectroscopy, thermogravimetric and elemental analyses, magnetic susceptibility, and EPR measurements. Magnetic studies on 1 and 2 demonstrated that both compounds exhibit appreciable deviation from typical paramagnetic behavior, and have a ground state S = 3/2, as expected for a Cr(III) ion, but with an exceptionally large zero-field uniaxial anisotropy parameter (D). EPR measurements on powder and single-crystal samples of 1 and 2 using 9.5, 34.5, and 239.2 GHz frequencies and over 4-295 K temperature fully support the magnetization results and show that D = +2.4 cm(-1), the largest and sign-assigned D-value so far reported for an octahedral Cr(III)-containing, molecular compound. Ligand field analysis of results from CASSCF and NEVPT2-correlated electronic structure calculations on Cr(OH)6(3-) model complexes allowed to unravel the crucial role of the second coordination sphere of Cr(III) for the unusually large magnetic anisotropy reflected by the experimental value of D. The newly developed theoretical modeling, combined with the synthetic procedure for producing such unusual magnetic molecules in a well-defined and essentially magnetically isolated environment, appears to be a versatile new research area.
Dzitko, H.
1995-06-23
The subject of this thesis is the nuclear core of the sun. The first part is theoretical and concerns neutrino flux predictions. A precise description of the solar plasma is necessary to predict boron, beryllium and CNO cycle neutrinos. We treat here the nuclear reaction rates. They are mainly determined by the cross sections and the enhancement factors due to plasma particles, the co-called screening factors. We have discussed the various possible formalisms that could be used in stellar evolution and performed direct calculations of screened cross sections. We concluded that the screening prescriptions which have been used so far in stellar evolution should be replaced by the Mitler formalism. Next, we examine the cross section uncertainties and we show that it is possible to get a better agreement between theory and experiment. Discrepancies between the gallium experiments and the calculations suggest that we should go beyond the classical solar model. This has motivated our study on possible magnetic fields deeply buried in the solar core. We discuss here the influence of a magnetic pressure perturbation on solar evolution. In the experimental part of this work, we deal with the GOLF experiment, one of the three helio-seismological experiments on board the space probe SOHO. The purpose of this instrument is the study of the global oscillation modes in the frequency range 10{sup -7} to 6 10{sup -3} Hz with a sensitivity for frequencies higher than 2 10{sup -4} Hz of about 1 mm/s over 20 days of continuous integration at counting rates of 12 10{sup 6} cs/s. One part of this work was devoted to the precise characterization of the photomultipliers and their associated electronics in order to select them according to their intrinsic performances. This step was followed by long duration tests of three weeks simulating as well as possible the flight conditions. We show that the detection chain effectively meets the stability requirements of around 10{sup -7} by
Lipase catalyse glycerolysis for kinetic resolution of racemates.
Dlugy, C; Wolfson, A
2007-09-01
Candida antarctica lipase B catalyzed kinetic resolution of representative secondary alcohols, esters, and amine was successfully performed using triacetin or glycerol as solvents and acyl donor/acceptor. High conversions and enantioselectivities were achieved and the product was easily separated by simple extraction with diethyl ether.
Cohen, Andrew [Boston Univ., MA (United States); Schmaltz, Martin [Boston Univ., MA (United States); Katz, Emmanuel [Boston Univ., MA (United States); Rebbi, Claudio [Boston Univ., MA (United States); Glashow, Sheldon [Boston Univ., MA (United States); Brower, Richard [Boston Univ., MA (United States); Pi, So-Young [Boston Univ., MA (United States)
2016-09-30
This award supported a broadly based research effort in theoretical particle physics, including research aimed at uncovering the laws of nature at short (subatomic) and long (cosmological) distances. These theoretical developments apply to experiments in laboratories such as CERN, the facility that operates the Large Hadron Collider outside Geneva, as well as to cosmological investigations done using telescopes and satellites. The results reported here apply to physics beyond the so-called Standard Model of particle physics; physics of high energy collisions such as those observed at the Large Hadron Collider; theoretical and mathematical tools and frameworks for describing the laws of nature at short distances; cosmology and astrophysics; and analytic and computational methods to solve theories of short distance physics. Some specific research accomplishments include + Theories of the electroweak interactions, the forces that give rise to many forms of radioactive decay; + Physics of the recently discovered Higgs boson. + Models and phenomenology of dark matter, the mysterious component of the universe, that has so far been detected only by its gravitational effects. + High energy particles in astrophysics and cosmology. + Algorithmic research and Computational methods for physics of and beyond the Standard Model. + Theory and applications of relativity and its possible limitations. + Topological effects in field theory and cosmology. + Conformally invariant systems and AdS/CFT. This award also supported significant training of students and postdoctoral fellows to lead the research effort in particle theory for the coming decades. These students and fellows worked closely with other members of the group as well as theoretical and experimental colleagues throughout the physics community. Many of the research projects funded by this grant arose in response to recently obtained experimental results in the areas of particle physics and cosmology. We describe a few of
Reflections on theoretical pragmatics
黄衍
2001-01-01
This paper provides a critical survey of theoretical pragmatics in contemporary linguistics. Among the topics that are addressed in the essay include the Anglo-American, and European Continental schools of thought;neo-Gricean pragmatic, and Relevance theories, the pragmatics-semantics interface; and the pragmatics-syntax interface.
Friedrich, Harald
2017-01-01
This expanded and updated well-established textbook contains an advanced presentation of quantum mechanics adapted to the requirements of modern atomic physics. It includes topics of current interest such as semiclassical theory, chaos, atom optics and Bose-Einstein condensation in atomic gases. In order to facilitate the consolidation of the material covered, various problems are included, together with complete solutions. The emphasis on theory enables the reader to appreciate the fundamental assumptions underlying standard theoretical constructs and to embark on independent research projects. The fourth edition of Theoretical Atomic Physics contains an updated treatment of the sections involving scattering theory and near-threshold phenomena manifest in the behaviour of cold atoms (and molecules). Special attention is given to the quantization of weakly bound states just below the continuum threshold and to low-energy scattering and quantum reflection just above. Particular emphasis is laid on the fundamen...
Compendium of theoretical physics
Wachter, Armin
2006-01-01
Mechanics, Electrodynamics, Quantum Mechanics, and Statistical Mechanics and Thermodynamics comprise the canonical undergraduate curriculum of theoretical physics. In Compendium of Theoretical Physics, Armin Wachter and Henning Hoeber offer a concise, rigorous and structured overview that will be invaluable for students preparing for their qualifying examinations, readers needing a supplement to standard textbooks, and research or industrial physicists seeking a bridge between extensive textbooks and formula books. The authors take an axiomatic-deductive approach to each topic, starting the discussion of each theory with its fundamental equations. By subsequently deriving the various physical relationships and laws in logical rather than chronological order, and by using a consistent presentation and notation throughout, they emphasize the connections between the individual theories. The reader’s understanding is then reinforced with exercises, solutions and topic summaries. Unique Features: Every topic is ...
Robustness - theoretical framework
Sørensen, John Dalsgaard; Rizzuto, Enrico; Faber, Michael H.
2010-01-01
More frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure combined with increased requirements to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new struct...... of this fact sheet is to describe a theoretical and risk based framework to form the basis for quantification of robustness and for pre-normative guidelines....
Electrochemical kinetics theoretical aspects
Vetter, Klaus J
1967-01-01
Electrochemical Kinetics: Theoretical Aspects focuses on the processes, methodologies, reactions, and transformations in electrochemical kinetics. The book first offers information on electrochemical thermodynamics and the theory of overvoltage. Topics include equilibrium potentials, concepts and definitions, electrical double layer and electrocapillarity, and charge-transfer, diffusion, and reaction overvoltage. Crystallization overvoltage, total overvoltage, and resistance polarization are also discussed. The text then examines the methods of determining electrochemical reaction mechanisms
Theoretical Delay Time Distributions
Nelemans, Gijs; Bours, Madelon
2012-01-01
We briefly discuss the method of population synthesis to calculate theoretical delay time distributions of type Ia supernova progenitors. We also compare the results of the different research groups and conclude that although one of the main differences in the results for single degenerate progenitors is the retention efficiency with which accreted hydrogen is added to the white dwarf core, this cannot explain all the differences.
Theoretical Delay Time Distributions
Nelemans, Gijs; Toonen, Silvia; Bours, Madelon
2013-01-01
We briefly discuss the method of population synthesis to calculate theoretical delay time distributions of Type Ia supernova progenitors. We also compare the results of different research groups and conclude that, although one of the main differences in the results for single degenerate progenitors is the retention efficiency with which accreted hydrogen is added to the white dwarf core, this alone cannot explain all the differences.
Silicene: Recent theoretical advances
Lew Yan Voon, L. C.
2016-04-14
Silicene is a two-dimensional allotrope of silicon with a puckered hexagonal structure closely related to the structure of graphene and that has been predicted to be stable. To date, it has been successfully grown in solution (functionalized) and on substrates. The goal of this review is to provide a summary of recent theoretical advances in the properties of both free-standing silicene as well as in interaction with molecules and substrates, and of proposed device applications.
MARKETING MIX THEORETICAL ASPECTS
Margarita Išoraitė
2016-01-01
Aim of article is to analyze marketing mix theoretical aspects. The article discusses that marketing mix is one of the main objectives of the marketing mix elements for setting objectives and marketing budget measures. The importance of each element depends not only on the company and its activities, but also on the competition and time. All marketing elements are interrelated and should be seen in the whole of their actions. Some items may have greater importance than others; it depends main...
Robustness - theoretical framework
Sørensen, John Dalsgaard; Rizzuto, Enrico; Faber, Michael H.
2010-01-01
More frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure combined with increased requirements to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new struct...... of this fact sheet is to describe a theoretical and risk based framework to form the basis for quantification of robustness and for pre-normative guidelines....
Theoretical numerical analysis
Wendroff, Burton
1966-01-01
Theoretical Numerical Analysis focuses on the presentation of numerical analysis as a legitimate branch of mathematics. The publication first elaborates on interpolation and quadrature and approximation. Discussions focus on the degree of approximation by polynomials, Chebyshev approximation, orthogonal polynomials and Gaussian quadrature, approximation by interpolation, nonanalytic interpolation and associated quadrature, and Hermite interpolation. The text then ponders on ordinary differential equations and solutions of equations. Topics include iterative methods for nonlinear systems, matri
Local, nonlocal quantumness and information theoretic measures
Agrawal, Pankaj; Sazim, Sk; Chakrabarty, Indranil; Pati, Arun K.
2016-08-01
It has been suggested that there may exist quantum correlations that go beyond entanglement. The existence of such correlations can be revealed by information theoretic quantities such as quantum discord, but not by the conventional measures of entanglement. We argue that a state displays quantumness, that can be of local and nonlocal origin. Information theoretic measures not only characterize the nonlocal quantumness, but also the local quantumness, such as the “local superposition”. This can be a reason, why such measures are nonzero, when there is no entanglement. We consider a generalized version of the Werner state to demonstrate the interplay of local quantumness, nonlocal quantumness and classical mixedness of a state.
Theoretical Developments in SUSY
Shifman, M.
2009-01-01
I am proud that I was personally acquainted with Julius Wess. We first met in 1999 when I was working on the Yuri Golfand Memorial Volume (The Many Faces of the Superworld, World Scientific, Singapore, 2000). I invited him to contribute, and he accepted this invitation with enthusiasm. After that, we met many times, mostly at various conferences in Germany and elsewhere. I was lucky to discuss with Julius questions of theoretical physics, and hear his recollections on how supersymmetry was born. In physics Julius was a visionary, who paved the way to generations of followers. In everyday life he was a kind and modest person, always ready to extend a helping hand to people who were in need of his help. I remember him telling me how concerned he was about the fate of theoretical physicists in Eastern Europe after the demise of communism. His ties with Israeli physicists bore a special character. I am honored by the opportunity to contribute an article to the Julius Wess Memorial Volume. I will review theoretical developments of the recent years in non-perturbative supersymmetry.
Theoretical developments in SUSY
Shifman, M. [University of Minnesota, William I. Fine Theoretical Physics Institute, Minneapolis, MN (United States)
2009-01-15
I am proud that I was personally acquainted with Julius Wess. We first met in 1999 when I was working on the Yuri Golfand Memorial Volume (The Many Faces of the Superworld, World Scientific, Singapore, 2000). I invited him to contribute, and he accepted this invitation with enthusiasm. After that, we met many times, mostly at various conferences in Germany and elsewhere. I was lucky to discuss with Julius questions of theoretical physics, and hear his recollections on how supersymmetry was born. In physics Julius was a visionary, who paved the way to generations of followers. In everyday life he was a kind and modest person, always ready to extend a helping hand to people who were in need of his help. I remember him telling me how concerned he was about the fate of theoretical physicists in Eastern Europe after the demise of communism. His ties with Israeli physicists bore a special character. I am honored by the opportunity to contribute an article to the Julius Wess Memorial Volume. I review theoretical developments of the recent years in non-perturbative supersymmetry. (orig.)
Düğdü, Esra; Ünver, Yasemin; Ünlüer, Dilek; Tanak, Hasan; Sancak, Kemal; Köysal, Yavuz; Işık, Şamil
2013-05-01
4-(4-Methoxyphenethyl)-3,5-dimethyl-4H-1,2,4-triazole (3) was synthesized from the reaction of ethyl N'-acetylacetohydrazonate (1) with 2-(4-methoxyphenyl)ethanamine (2). The structure of the title compound 3 has been inferred through IR, 1H/13C NMR, mass spectrometry, elemental analyses and combination of X-ray crystallography and theoretical methods. In addition to the molecular geometry from X-ray determination, the molecular geometry and vibrational frequencies of the title compound 3 in the ground state, were calculated using the density functional method (B3LYP) with the 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure and the theoretical vibrational frequencies show good agreement with experimental values. The nonlinear optical properties are also addressed theoretically. The predicted nonlinear optical properties of 3 are greater than ones of urea. In addition, DFT calculations of molecular electrostatic potentials and frontier molecular orbitals of the title compound were carried out at the B3LYP/6-31G(d) level of theory.
Theoretical Astrophysics at Fermilab
2004-01-01
The Theoretical Astrophysics Group works on a broad range of topics ranging from string theory to data analysis in the Sloan Digital Sky Survey. The group is motivated by the belief that a deep understanding of fundamental physics is necessary to explain a wide variety of phenomena in the universe. During the three years 2001-2003 of our previous NASA grant, over 120 papers were written; ten of our postdocs went on to faculty positions; and we hosted or organized many workshops and conferences. Kolb and collaborators focused on the early universe, in particular and models and ramifications of the theory of inflation. They also studied models with extra dimensions, new types of dark matter, and the second order effects of super-horizon perturbations. S tebbins, Frieman, Hui, and Dodelson worked on phenomenological cosmology, extracting cosmological constraints from surveys such as the Sloan Digital Sky Survey. They also worked on theoretical topics such as weak lensing, reionization, and dark energy. This work has proved important to a number of experimental groups [including those at Fermilab] planning future observations. In general, the work of the Theoretical Astrophysics Group has served as a catalyst for experimental projects at Fennilab. An example of this is the Joint Dark Energy Mission. Fennilab is now a member of SNAP, and much of the work done here is by people formerly working on the accelerator. We have created an environment where many of these people made transition from physics to astronomy. We also worked on many other topics related to NASA s focus: cosmic rays, dark matter, the Sunyaev-Zel dovich effect, the galaxy distribution in the universe, and the Lyman alpha forest. The group organized and hosted a number of conferences and workshop over the years covered by the grant. Among them were:
Institute for Theoretical Physics
Giddings, S.B.; Ooguri, H.; Peet, A.W.; Schwarz, J.H.
1998-06-01
String theory is the only serious candidate for a unified description of all known fundamental particles and interactions, including gravity, in a single theoretical framework. Over the past two years, activity in this subject has grown rapidly, thanks to dramatic advances in understanding the dynamics of supersymmetric field theories and string theories. The cornerstone of these new developments is the discovery of duality which relates apparently different string theories and transforms difficult strongly coupled problems of one theory into weakly coupled problems of another theory.
Theoretical astrophysics an introduction
Bartelmann, Matthias
2013-01-01
A concise yet comprehensive introduction to the central theoretical concepts of modern astrophysics, presenting hydrodynamics, radiation, and stellar dynamics all in one textbook. Adopting a modular structure, the author illustrates a small number of fundamental physical methods and principles, which are sufficient to describe and understand a wide range of seemingly very diverse astrophysical phenomena and processes. For example, the formulae that define the macroscopic behavior of stellar systems are all derived in the same way from the microscopic distribution function. This function it
Shivamoggi, Bhimsen K
1998-01-01
"Although there are many texts and monographs on fluid dynamics, I do not know of any which is as comprehensive as the present book. It surveys nearly the entire field of classical fluid dynamics in an advanced, compact, and clear manner, and discusses the various conceptual and analytical models of fluid flow." - Foundations of Physics on the first edition. Theoretical Fluid Dynamics functions equally well as a graduate-level text and a professional reference. Steering a middle course between the empiricism of engineering and the abstractions of pure mathematics, the author focuses
Theoretical Optics An Introduction
Römer, Hartmann
2004-01-01
Starting from basic electrodynamics, this volume provides a solid, yet concise introduction to theoretical optics, containing topics such as nonlinear optics, light-matter interaction, and modern topics in quantum optics, including entanglement, cryptography, and quantum computation. The author, with many years of experience in teaching and research, goes way beyond the scope of traditional lectures, enabling readers to keep up with the current state of knowledge. Both content and presentation make it essential reading for graduate and phD students as well as a valuable reference for researche
Theoretical solid state physics
Haug, Albert
2013-01-01
Theoretical Solid State Physics, Volume 1 focuses on the study of solid state physics. The volume first takes a look at the basic concepts and structures of solid state physics, including potential energies of solids, concept and classification of solids, and crystal structure. The book then explains single-electron approximation wherein the methods for calculating energy bands; electron in the field of crystal atoms; laws of motion of the electrons in solids; and electron statistics are discussed. The text describes general forms of solutions and relationships, including collective electron i
Theoretical Particle Astrophysics
Kamionkowski, Marc
2013-08-07
Abstract: Theoretical Particle Astrophysics The research carried out under this grant encompassed work on the early Universe, dark matter, and dark energy. We developed CMB probes for primordial baryon inhomogeneities, primordial non-Gaussianity, cosmic birefringence, gravitational lensing by density perturbations and gravitational waves, and departures from statistical isotropy. We studied the detectability of wiggles in the inflation potential in string-inspired inflation models. We studied novel dark-matter candidates and their phenomenology. This work helped advance the DoE's Cosmic Frontier (and also Energy and Intensity Frontiers) by finding synergies between a variety of different experimental efforts, by developing new searches, science targets, and analyses for existing/forthcoming experiments, and by generating ideas for new next-generation experiments.
Theoretical physics 5 thermodynamics
Nolting, Wolfgang
2017-01-01
This concise textbook offers a clear and comprehensive introduction to thermodynamics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, defining macroscopic variables, such as internal energy, entropy and pressure,together with thermodynamic principles. The first part of the book introduces the laws of thermodynamics and thermodynamic potentials. More complex themes are covered in the second part of the book, which describes phases and phase transitions in depth. Ideally suited to undergraduate students with some grounding in classical mechanics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series cove...
Theoretical Molecular Biophysics
Scherer, Philipp
2010-01-01
"Theoretical Molecular Biophysics" is an advanced study book for students, shortly before or after completing undergraduate studies, in physics, chemistry or biology. It provides the tools for an understanding of elementary processes in biology, such as photosynthesis on a molecular level. A basic knowledge in mechanics, electrostatics, quantum theory and statistical physics is desirable. The reader will be exposed to basic concepts in modern biophysics such as entropic forces, phase separation, potentials of mean force, proton and electron transfer, heterogeneous reactions coherent and incoherent energy transfer as well as molecular motors. Basic concepts such as phase transitions of biopolymers, electrostatics, protonation equilibria, ion transport, radiationless transitions as well as energy- and electron transfer are discussed within the frame of simple models.
Social Security: Theoretical Aspects
O. I. Kashnik
2013-01-01
Full Text Available The paper looks at the phenomena of security and social security from the philosophical, sociological and psychological perspective. The undertaken analysis of domestic and foreign scientific materials demonstrates the need for interdisciplinary studies, including pedagogy and education, aimed at developing the guidelines for protecting the social system from destruction. The paper defines the indicators, security level indices and their assessment methods singled out from the analytical reports and security studies by the leading Russian sociological centers and international expert organizations, including the United Nations.The research is aimed at finding out the adequate models of personal and social security control systems at various social levels. The theoretical concepts can be applied by the teachers of the Bases of Life Safety course, the managers and researches developing the assessment criteria and security indices of educational environment evaluation, as well as the methods of diagnostics and expertise of educational establishments from the security standpoint.
Theoretical physics 3 electrodynamics
Nolting, Wolfgang
2016-01-01
This textbook offers a clear and comprehensive introduction to electrodynamics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series. The first part of the book describes the interaction of electric charges and magnetic moments by introducing electro- and magnetostatics. The second part of the book establishes deeper understanding of electrodynamics with the Maxwell equations, quasistationary fields and electromagnetic fields. All sections are accompanied by a detailed introduction to the math needed. Ideally suited to undergraduate students with some grounding in classical and analytical mechanics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful Germa...
Computability-theoretic learning complexity.
Case, John; Kötzing, Timo
2012-07-28
Initially discussed are some of Alan Turing's wonderfully profound and influential ideas about mind and mechanism-including regarding their connection to the main topic of the present study, which is within the field of computability-theoretic learning theory. Herein is investigated the part of this field concerned with the algorithmic, trial-and-error inference of eventually correct programs for functions from their data points. As to the main content of this study: in prior papers, beginning with the seminal work by Freivalds et al. in 1995, the notion of intrinsic complexity is used to analyse the learning complexity of sets of functions in a Gold-style learning setting. Herein are pointed out some weaknesses of this notion. Offered is an alternative based on epitomizing sets of functions-sets that are learnable under a given learning criterion, but not under other criteria that are not at least as powerful. To capture the idea of epitomizing sets, new reducibility notions are given based on robust learning (closure of learning under certain sets of computable operators). Various degrees of epitomizing sets are characterized as the sets complete with respect to corresponding reducibility notions! These characterizations also provide an easy method for showing sets to be epitomizers, and they are then employed to prove several sets to be epitomizing. Furthermore, a scheme is provided to generate easily very strong epitomizers for a multitude of learning criteria. These strong epitomizers are the so-called self-learning sets, previously applied by Case & Kötzing in 2010. These strong epitomizers can be easily generated and employed in a myriad of settings to witness with certainty the strict separation in learning power between the criteria so epitomized and other not as powerful criteria!
Walch, Stephen P.; Duchovic, Ronald J.
1991-01-01
Computed energies and geometries are reported which, combined with previously published calculations, permit a global representation of the potential energy surface for the reaction H + O2 yields HO2(asterisk) yields OH + O. These new calculations characterize the potential energy surface (PES) for all H atom angles of approach to O2 and for the region of the inner repulsive wall. The region of the T-shaped H-O2 exchange saddle point is connected with the constrained energy minimum (CEM) path, and a new collinear H-O2 exchange saddle point is characterized which lies only 9 kcal/mol above the H + O2 asymptote. A vibrational analysis which utilizes local cubic and quartic polynomial representations of the PES along the CEM path has been carried out. Optimal geometries, energies, and harmonic frequencies are reported along with anharmonic analyses for the O2 and OH asymptotes and for the HO2 minimum region of the PES.
Theoretical Approaches to Coping
Sofia Zyga
2013-01-01
Full Text Available Introduction: Dealing with stress requires conscious effort, it cannot be perceived as equal to individual's spontaneous reactions. The intentional management of stress must not be confused withdefense mechanisms. Coping differs from adjustment in that the latter is more general, has a broader meaning and includes diverse ways of facing a difficulty.Aim: An exploration of the definition of the term "coping", the function of the coping process as well as its differentiation from other similar meanings through a literature review.Methodology: Three theoretical approaches of coping are introduced; the psychoanalytic approach; approaching by characteristics; and the Lazarus and Folkman interactive model.Results: The strategic methods of the coping approaches are described and the article ends with a review of the approaches including the functioning of the stress-coping process , the classificationtypes of coping strategies in stress-inducing situations and with a criticism of coping approaches.Conclusions: The comparison of coping in different situations is difficult, if not impossible. The coping process is a slow process, so an individual may select one method of coping under one set ofcircumstances and a different strategy at some other time. Such selection of strategies takes place as the situation changes.
Synthesis and characterization of triglyceride based thermosetting polymers
Can, Erde
2005-07-01
Plant oils, which are found in abundance in all parts of the world and are easily replenished annually, have the potential to replace petroleum as a chemical feedstock for making polymers. Within the past few years, there has been growing interest to use triglycerides as the basic constituent of thermosetting polymers with the necessary rigidity, strength and glass transition temperatures required for engineering applications. Plant oils are not polymerizable in their natural form, however various functional groups that can polymerize can easily be attached to the triglyceride structure making them ideal cross-linking monomers for thermosetting liquid molding resins. Through this research project a number of thermosetting liquid molding resins based on soybean and castor oil, which is a specialty oil with hydroxyls on its fatty acids, have been developed. The triglyceride based monomers were prepared via the malination of the alcoholysis products of soybean and castor oil with various polyols, such as pentaerythritol, glycerol, and Bisphenol A propoxylate. The malinated glycerides were then cured in the presence of a reactive diluent, such as styrene, to form rigid glassy materials with a wide range of properties. In addition to maleate half-esters, methacrylates were also introduced to the glyceride structure via methacrylation of the soybean oil glycerolysis product with methacrylic anhydride. This product, which contains methacrylic acid as by-product, and its blends with styrene also gave rigid materials when cured. The triglyceride based monomers were characterized via conventional spectroscopic techniques. Time resolved FTIR analysis was used to determine the curing kinetics and the final conversions of polymerization of the malinated glyceride-styrene blends. Dynamic Mechanical Analysis (DMA) was used to determine the thermomechanical behavior of these polymers and other mechanical properties were determined via standard mechanical tests. The use of lignin
Order Theoretical Semantic Recommendation
Joslyn, Cliff A.; Hogan, Emilie A.; Paulson, Patrick R.; Peterson, Elena S.; Stephan, Eric G.; Thomas, Dennis G.
2013-07-23
Mathematical concepts of order and ordering relations play multiple roles in semantic technologies. Discrete totally ordered data characterize both input streams and top-k rank-ordered recommendations and query output, while temporal attributes establish numerical total orders, either over time points or in the more complex case of startend temporal intervals. But also of note are the fully partially ordered data, including both lattices and non-lattices, which actually dominate the semantic strcuture of ontological systems. Scalar semantic similarities over partially-ordered semantic data are traditionally used to return rank-ordered recommendations, but these require complementation with true metrics available over partially ordered sets. In this paper we report on our work in the foundations of partial order measurement in ontologies, with application to top-k semantic recommendation in workflows.
Zatsikha, Yuriy V; Nemez, Dion B; Davis, Rebecca L; Singh, Simarpreet; Herbert, David E; King, Alex J; Ziegler, Christopher J; Nemykin, Victor N
2017-07-19
Several BOPHY derivatives with and without ferrocene fragments, and with electron-withdrawing ester groups appended to the β-pyrrolic positions have been prepared and characterized by NMR, UV/Vis near-infrared (NIR), high-resolution mass spectrometry, and fluorescence spectroscopy, as well as X-ray crystallography. The redox properties of new BOPHYs were probed by electrochemical (cyclic and differential pulse voltammetry) and spectroelectrochemical methods. In an attempt to prepare BOPHY derivatives with a cyano group at the bridging position using a similar approach for BODIPY cyanation, adducts from the nucleophilic attack of the cyanide anion on the bridging position in BOPHY have been isolated and characterized by spectroscopic methods. Oxidation of such adducts, however, resulted in formation of either the starting BOPHYs, or partial extrusion of the BF2 fragment from the BOPHY core, which was confirmed by spectroscopy and X-ray crystallography. DFT and TDDFT calculations on all target materials correlate well with the experimental data, and suggest the dramatic reduction of the nitrogen atom basicity at the hydrazine bridge of the BOPHY upon introduction of the cyano group at the bridging-carbon atom. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
The Basic Theoretical Framework
Loeb, Abraham
Cosmology is by now a mature experimental science. We are privileged to live at a time when the story of genesis (how the Universe started and developed) can be critically explored by direct observations. Looking deep into the Universe through powerful telescopes, we can see images of the Universe when it was younger because of the finite time it takes light to travel to us from distant sources. Existing data sets include an image of the Universe when it was 0.4 million years old (in the form of the cosmic microwave background), as well as images of individual galaxies when the Universe was older than a billion years. But there is a serious challenge: in between these two epochs was a period when the Universe was dark, stars had not yet formed, and the cosmic microwave background no longer traced the distribution of matter. And this is precisely the most interesting period, when the primordial soup evolved into the rich zoo of objects we now see. The observers are moving ahead along several fronts. The first involves the construction of large infrared telescopes on the ground and in space, that will provide us with new photos of the first galaxies. Current plans include ground-based telescopes which are 24-42 m in diameter, and NASA's successor to the Hubble Space Telescope, called the James Webb Space Telescope. In addition, several observational groups around the globe are constructing radio arrays that will be capable of mapping the three-dimensional distribution of cosmic hydrogen in the infant Universe. These arrays are aiming to detect the long-wavelength (redshifted 21-cm) radio emission from hydrogen atoms. The images from these antenna arrays will reveal how the non-uniform distribution of neutral hydrogen evolved with cosmic time and eventually was extinguished by the ultra-violet radiation from the first galaxies. Theoretical research has focused in recent years on predicting the expected signals for the above instruments and motivating these ambitious
Theoretically Optimal Distributed Anomaly Detection
National Aeronautics and Space Administration — A novel general framework for distributed anomaly detection with theoretical performance guarantees is proposed. Our algorithmic approach combines existing anomaly...
Chen, H.; Jacobson, D.B.; Freiser, B.S. [Purdue Univ., West Lafayette, IN (United States). H.C. Brown Lab. of Chemistry
1999-04-26
Fe{sup +}-2,3-didehydropyrazine (2) has been generated and its reactivity with simple olefins and alkynes studied by using Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. 2, which is prepared by dehalogenation of chloropyrazine by Fe{sup +}, undergoes a simple adduct formation (no ligand coupling) with ethene and ethene-d{sub 4}. Ethyne also yields adduct formation; however, ligand coupling has clearly occurred in this reaction. Interestingly, reactions with propene and isobutene yield the same products with similar product distributions. Again, ligand coupling is involved and a metal-centered mechanism featuring activation of the allylic carbon-hydrogen bonds is proposed. Propyne, allene, 1-butene, and cis-2-butene yield a variety of products with 2. However, 2 yields exclusive dehydrogenation with 1,3-butadiene to generate FeC{sub 8}H{sub 6}N{sub 2}{sup +}. CID results suggest that this FeC{sub 8}H{sub 6}N{sub 2}{sup +} ion consists of quinoxaline bound to Fe{sup +}. Ligand displacement reactions yield a bond dissociation energy of 47 {+-} 5 kcal/mol for D{degree}(Fe{sup +}-quinoxaline). FeC{sub 4}H{sub 2}N{sub 2}{sup +} ion (2) has also been investigated theoretically. Density functional calculations predicted that the ground state of 2,3-didehydropyrazine is the triplet state, with the singlet state being 9.9 kcal/mol higher than the triplet state. 2 has C{sub 2{nu}} symmetry with the metal center coplanar with the 2,3-didehydropyrazine ring. 2 has a sextet ground state with doublet and quartet states 4.9 and 6.8 kcal/mol higher, respectively. The bond dissociation energy D{degree}(Fe{sup +}-C{sub 4}H{sub 2}N{sub 2}) for the sextet ground state is computed to be 87 {+-} 10 kcal/mol.
Anasori, Babak [Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Dahlqvist, Martin; Lu, Jun; Hultman, Lars; Eklund, Per; Rosén, Johanna [Thin Film Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Halim, Joseph [Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Thin Film Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Moon, Eun Ju; Hosler, Brian C.; May, Steven J.; Barsoum, Michel W., E-mail: barsoumw@drexel.edu [Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Caspi, El' ad N. [Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Physics Department, Nuclear Research Centre - Negev, PO Box 9001, 84190 Beer-Sheva (Israel)
2015-09-07
Herein, we report on the phase stabilities and crystal structures of two newly discovered ordered, quaternary MAX phases—Mo{sub 2}TiAlC{sub 2} and Mo{sub 2}Ti{sub 2}AlC{sub 3}—synthesized by mixing and heating different elemental powder mixtures of mMo:(3-m)Ti:1.1Al:2C with 1.5 ≤ m ≤ 2.2 and 2Mo: 2Ti:1.1Al:2.7C to 1600 °C for 4 h under Ar flow. In general, for m ≥ 2 an ordered 312 phase, (Mo{sub 2}Ti)AlC{sub 2}, was the majority phase; for m < 2, an ordered 413 phase (Mo{sub 2}Ti{sub 2})AlC{sub 3}, was the major product. The actual chemistries determined from X-ray photoelectron spectroscopy (XPS) are Mo{sub 2}TiAlC{sub 1.7} and Mo{sub 2}Ti{sub 1.9}Al{sub 0.9}C{sub 2.5}, respectively. High resolution scanning transmission microscopy, XPS and Rietveld analysis of powder X-ray diffraction confirmed the general ordered stacking sequence to be Mo-Ti-Mo-Al-Mo-Ti-Mo for Mo{sub 2}TiAlC{sub 2} and Mo-Ti-Ti-Mo-Al-Mo-Ti-Ti-Mo for Mo{sub 2}Ti{sub 2}AlC{sub 3}, with the carbon atoms occupying the octahedral sites between the transition metal layers. Consistent with the experimental results, the theoretical calculations clearly show that M layer ordering is mostly driven by the high penalty paid in energy by having the Mo atoms surrounded by C in a face-centered configuration, i.e., in the center of the M{sub n+1}X{sub n} blocks. At 331 GPa and 367 GPa, respectively, the Young's moduli of the ordered Mo{sub 2}TiAlC{sub 2} and Mo{sub 2}Ti{sub 2}AlC{sub 3} are predicted to be higher than those calculated for their ternary end members. Like most other MAX phases, because of the high density of states at the Fermi level, the resistivity measurement over 300 to 10 K for both phases showed metallic behavior.
Demet Gürbüz
2016-12-01
Full Text Available 5,6-Dichloro/dimethyl-2-(2´,3´/2´,4´/2´,5´/3´,4´/3´,5´-dimethoxyphenyl-1H-benzimidazoles were synthesized and characterized by using analytical data, FT-IR, FT-Raman, NMR, ESI-MS and fl uorescence spectroscopy. The optimized molecular geometry, zero point energy, dipole moment, ESE, band gap and charge distributions were calculated by Gaussian 09 using Density Functional Theory (DFT, RB3LYP with 6-31++G(d,p basis set. According to the calculations, the molecules have structures with various torsion angles between the benzimidazole and benzene rings from 9.7º to 47.8º. The calculated energy values with ZPE correction and DFT show that the methyl derivatives are more stable than the chloro forms. 3´,4´-Dimethoxy derivatives have higher decomposition points in comparison with the other compounds in series. The chlorine atoms of 5,6-dichloro-2- (2´,3´/2´,4´/2´,5´/3´,4´/3´,5´-dimethoxyphenyl-1H-benzimidazoles are positively charged whereas the C5 and C6 carbon atoms are negatively charged due to the attached chlorine atoms, in virtue of the electron withdrawing characteristic of the imidazole part of the benzimidazole ring. Also, some calculated prominent bond lengths and bond angles were discussed.
A Comparison of Experimental and Theoretical Results for Magnetic Bearings
Hibbs, Robert I., Jr.; Scharrer, Joseph K.; Galvin, Bonnie A.; Galvin, Mark W.
2000-01-01
A comprehensive program was undertaken to experimentally characterize the static and dynamic characteristics of a heteropolar magnetic bearing and to develop nonlinear theoretical models capable of accurately predicting magnetic bearing performance. This paper presents the results for the static characteristics of the magnetic bearing and a comparison with the predictions from the analytical model. The results indicate that the nonlinear theoretical model can accurately predict the static characteristics of the magnetic bearing.
2nd International Conference on Proof-Theoretic Semantics
Schroeder-Heister, Peter
2016-01-01
This volume is the first ever collection devoted to the field of proof-theoretic semantics. Contributions address topics including the systematics of introduction and elimination rules and proofs of normalization, the categorial characterization of deductions, the relation between Heyting's and Gentzen's approaches to meaning, knowability paradoxes, proof-theoretic foundations of set theory, Dummett's justification of logical laws, Kreisel's theory of constructions, paradoxical reasoning, and the defence of model theory. The field of proof-theoretic semantics has existed for almost 50 years, but the term itself was proposed by Schroeder-Heister in the 1980s. Proof-theoretic semantics explains the meaning of linguistic expressions in general and of logical constants in particular in terms of the notion of proof. This volume emerges from presentations at the Second International Conference on Proof-Theoretic Semantics in Tübingen in 2013, where contributing authors were asked to provide a self-contained descri...
Radu, Ioana; Kravtsov, Victor Ch; Ostrovsky, Serghei M; Reu, Oleg S; Krämer, Karl; Decurtins, Silvio; Liu, Shi-Xia; Klokishner, Sophia I; Baca, Svetlana G
2017-03-06
New tetranuclear and octanuclear mixed-valent cobalt(II/III) pivalate clusters, namely, [NaCo4(O2CCMe3)6(HO2CCMe3)2(teaH)2(N3)]·2H2O (in two polymorphic modifications, 1 and 1a) and [Co8(O2CCMe3)10(teaH)4(N3)](Me3CCO2)·MeCN·H2O (2) have been synthesized by ultrasonic treatment of a dinuclear cobalt(II) pivalate precursor with sodium azide and triethanolamine (teaH3) ligand in acetonitrile. The use of Dy(NO3)3·6H2O in a similar reaction led to the precipitation of a tetranuclear [NaCo4(O2CCMe3)4(teaH)2(N3)(NO3)2(H2O)2]·H2O (3) cluster and a heterometallic hexanuclear [Co3Dy3(OH)4(O2CCMe3)6(teaH)3(H2O)3](NO3)2·H2O (4) cluster. Single-crystal X-ray analysis showed that 1 (1a) and 3 consist of a tetranuclear pivalate/teaH3 mixed-ligand cluster [Co(II)2Co(III)2(O2CCMe3)4(teaH)2(N3)](+) decorated with sodium pivalates [Na(O2CCMe3)2(HO2CCMe3)2](-) (1 or 1a) or sodium nitrates [Na(NO3)2](-) (3) to form a square-pyramidal assembly. In 2, the cationic [Co8(O2CCMe3)10(teaH)4(N3)](+) cluster comprises a mixed-valent {Co(II)4Co(III)4} core encapsulated by an azide, 4 teaH(2-) alcoholamine ligands, and 10 bridging pivalates. Remarkably, in this core, the μ4-N3(-) ligand joins all four Co(II) atoms. The heterometallic hexanuclear compound 4 consists of a cationic [Co(III)3Dy(III)3(OH)4(O2CCMe3)6(teaH)3(H2O)3](2+) cluster, two NO3(-) anions, and a crystallization water molecule. The arrangement of metal atoms in 4 can be approximated as the assembly of a smaller equilateral triangle defined by three Dy sites with a Dy···Dy distance of 3.9 Å and a larger triangle formed by Co sites [Co···Co, 6.1-6.2 Å]. The interpretation of the magnetic properties of clusters 2-4 was performed in the framework of theoretical models, taking into account the structural peculiarities of clusters and their energy spectra. The behavior of clusters 2 and 3 containing Co(II) ions with orbitally nondegenerate ground states is determined by the zero-field splitting of these states and
Joy, Sucheta; Krämer, Tobias; Paul, Nanda D; Banerjee, Priyabrata; McGrady, John E; Goswami, Sreebrata
2011-10-17
The reaction of 3 equiv of the ligand 2-[(2-chlorophenyl)azo]pyridine (L(a)) or 2-[(4-chlorophenyl)azo]pyridine (L(b)) with 1 equiv of Cr(CO)(6) or Mo(CO)(6) in boiling n-octane afforded [Cr(L(a/b))(3)](0) (1a and 1b) and [Mo(L(a/b))(3)](0) (2a and 2b). The chemical oxidation reaction of these neutral complexes with I(2) in CH(2)Cl(2) provided access to air-stable one-electron-oxidized species as their triiodide (I(3)(-)) salts. The electronic structures of chromium and molybdenum centers coordinated by the three redox noninnocent ligands L(a/b) along with their redox partners have been elucidated by using a host of physical methods: X-ray crystallography, magnetic susceptibility measurements, nuclear magnetic resonance, cyclic voltammetry, absorption spectroscopy, electron paramagnetic resonance spectroscopy, and density functional theory. The four representative complexes, 1a, [1a]I(3), 2a, and [2a]I(3), have been characterized by X-ray crystallography. The results indicate a predominant azo-anion-radical description of the ligands in the neutral chromium(III) species, [Cr(III)(L(•-))(3)], affording a singlet ground state through strong metal-ligand antiferromagnetic coupling. All of the electrochemical processes are ligand-based; i.e., the half-filled (t(2g))(3) set of the Cr(III) d(3) ion remains unchanged throughout. The description of the molybdenum analogue is less clear-cut because mixing between metal- and ligand-based orbitals is more significant. On the basis of variations in net spin densities and orbital compositions, we argue that the oxidation events are again primarily ligand-based, although the electron density at the molybdenum center is clearly more variable than that at the chromium center in the corresponding series [1a](+), 1a, and [1a](-).
Theoretical chemistry advances and perspectives
Eyring, Henry
1980-01-01
Theoretical Chemistry: Advances and Perspectives, Volume 5 covers articles concerning all aspects of theoretical chemistry. The book discusses the mean spherical approximation for simple electrolyte solutions; the representation of lattice sums as Mellin-transformed products of theta functions; and the evaluation of two-dimensional lattice sums by number theoretic means. The text also describes an application of contour integration; a lattice model of quantum fluid; as well as the computational aspects of chemical equilibrium in complex systems. Chemists and physicists will find the book usef
Theoretical approaches to elections defining
Natalya V. Lebedeva
2011-01-01
Full Text Available Theoretical approaches to elections defining develop the nature, essence and content of elections, help to determine their place and a role as one of the major national law institutions in democratic system.
Fsusy and Field Theoretical Construction
Sedra, M B
2009-01-01
Following our previous work on fractional spin symmetries (FSS) \\cite{6, 7}, we consider here the construction of field theoretical models that are invariant under the $D=2(1/3,1/3)$ supersymmetric algebra.
Theoretical Foundations of Learning Communities
Jessup-Anger, Jody E.
2015-01-01
This chapter describes the historical and contemporary theoretical underpinnings of learning communities and argues that there is a need for more complex models in conceptualizing and assessing their effectiveness.
Theoretical Studies of Proton Radioactivity
Ldia S Ferreira; Enrico Maglione
2016-01-01
In the paper, we will discuss the most recent theoretical approaches developed by our group, to understand the mechanisms of decay by one proton emission, and the structure and shape of exotic nuclei at the limits of stability.
Euclid's Number-Theoretical Work
Zhang, Shaohua
2009-01-01
The object of this paper is to affirm the number-theoretical role of Euclid and the historical significance of Euclid's algorithm. We give a brief introduction about Euclid's number-theoretical work. Our study is the first to show that Euclid's algorithm is essentially equivalent with Division algorithm which is the basis of Theory of Divisibility. Note also that Euclid's algorithm implies Euclid's first theorem and Euclid's second theorem. Thus, in the nature of things, Euclid's algorithm is the most important number-theoretical work of Euclid. For this reason, we further summarize briefly the influence of Euclid's algorithm. It leads to the conclusion that Euclid's algorithm is the greatest number-theoretical achievement of the age.
THEORETICAL APPROACHES IN INTERNATIONAL RELATIONS ...
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understanding of the social dynamics of the world we live in. Theoretical approaches are also instrumental in shaping perceptions of what matters in international politics ... This implies that, as a technique of last resort, the military instrument.
A theoretical model of metal surface reactions
Shustorovich, E. (Eastman Kodak Co., Rochester, NY); Baetzold, R.C.; Muetterties, E.L.
1983-03-31
Metal surface reactions are modeled with a novel theoretical construct in which periodic trends can be scrutinized. The theoretical model is succinctly presented and a conspectus of periodic trends, based on the model, is explored. Periodic trends are discussed in the contexts of chemisorption bond energies, electron transfer between metal surface and adsorbate, stereochemical features of chemisorption states for closed-shell diatomic and linear X-CN or X-NC molecules, and hydrocarbon reactions. Hydrocarbon C-H bond-breaking processes are analyzed in terms of d-level occupancy, electron transfer, and stereochemistry of intermediates. Conceptually and computationally, the metal surface is characterized as a good electron donor: antibonding molecular orbitals of the adsorbate species appear to be significant contributors to the chemisorption bond and also play a decisive role in bond-breaking processes. No aspect of the model projections is inconsistent with the experimental data although the electronic characterization of some chemisorption states are counter to commonly held perceptions.
Recent theoretical progress on an information geometrodynamical approach to chaos
Cafaro, Carlo
2008-01-01
In this paper, we report our latest research on a novel theoretical information-geometric framework suitable to characterize chaotic dynamical behavior of arbitrary complex systems on curved statistical manifolds. Specifically, an information-geometric analogue of the Zurek-Paz quantum chaos criterion of linear entropy growth and an information-geometric characterization of chaotic (integrable) energy level statistics of a quantum antiferromagnetic Ising spin chain in a tilted (transverse) external magnetic field are presented.
Theoretical behaviorism meets embodied cognition : Two theoretical analyses of behavior
Keijzer, F.A.
2005-01-01
This paper aims to do three things: First, to provide a review of John Staddon's book Adaptive dynamics: The theoretical analysis of behavior. Second, to compare Staddon's behaviorist view with current ideas on embodied cognition. Third, to use this comparison to explicate some outlines for a theore
Theoretical behaviorism meets embodied cognition : Two theoretical analyses of behavior
Keijzer, F.A.
2005-01-01
This paper aims to do three things: First, to provide a review of John Staddon's book Adaptive dynamics: The theoretical analysis of behavior. Second, to compare Staddon's behaviorist view with current ideas on embodied cognition. Third, to use this comparison to explicate some outlines for a theore
Theoretical characterization of low-lying electronic states of FCO
Francisco, Joseph S.; Goldstein, Avery N.; Robb, Michael A.; Williams, Ian H.
1992-03-01
The electronic and vibrational spectra of the fluoroformyl radical FCO are discussed in the light of ab initio (CASSCF(5 in 4)/6-31+G* and UMP2/6-311G*) calculated adiabatic and vertical transition energies, and vibrational frequencies, for the X 2A', A 2A″, B 2A', and C 2A″ states. Results for the formyl radical HCO are also presented for comparison.
Theoretical characterization of aflatoxins and their phototoxic reactions
Guedes, Rita C.; Eriksson, Leif A.
2006-05-01
Key molecular properties are calculated for the 8 most common aflatoxins at the B3LYP/6-31 + G(d,p) level. Special attention is given the possibility of aflatoxins to generate reactive oxygen species (ROS). It is concluded that the excited triplet states of the aflatoxins have properties that make them very potent ROS generators, in addition to direct photoinduced addition reactions. The elevated toxicity of aflatoxin B1 is discussed in terms of its lower ionization potential, and the coincidence of higher lying triplet states with dominant low-lying singlet excitations, which enables rapid intersystem crossing and decay along the triplet channel to the T 1 state.
Theoretical characterization of the sulfilimine bond: Double or single?
Pichierri, Fabio
2010-03-01
Using quantum mechanical calculations in combination with AIM and NBO analyses, we investigate the properties of the sulfilimine bond, which has been recently detected in collagen IV [Vanacore et al., Science 325 (2009) 1230]. Contrary to the general belief that this is a double bond, -N dbnd S<, our analysis of the wavefunction of a model compound indicates it being a coordinate covalent (dative) single bond, -N ← S<, with a strong polarization towards nitrogen.
Mechanics lectures on theoretical physics
Sommerfeld, Arnold Johannes Wilhelm
1952-01-01
Mechanics: Lectures on Theoretical Physics, Volume I covers a general course on theoretical physics. The book discusses the mechanics of a particle; the mechanics of systems; the principle of virtual work; and d'alembert's principle. The text also describes oscillation problems; the kinematics, statics, and dynamics of a rigid body; the theory of relative motion; and the integral variational principles of mechanics. Lagrange's equations for generalized coordinates and the theory of Hamilton are also considered. Physicists, mathematicians, and students taking Physics courses will find the book
Theoretical Framework for Robustness Evaluation
Sørensen, John Dalsgaard
2011-01-01
This paper presents a theoretical framework for evaluation of robustness of structural systems, incl. bridges and buildings. Typically modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages’. However, although...... the importance of robustness for structural design is widely recognized the code requirements are not specified in detail, which makes the practical use difficult. This paper describes a theoretical and risk based framework to form the basis for quantification of robustness and for pre-normative guidelines...
Group theoretical approach to entanglement
Korbicz, J K
2006-01-01
We examine a potential relevance of methods of harmonic analysis for the study of quantum entanglement. By changing the mathematical object representing quantum states, we reformulate the separability problem in group-theoretical terms. We also translate the positivity of partial transpose (PPT) criterion and one of the necessary-and-sufficient criteria for pure states to the group-theoretical language. The formal relation of our formalism to local hidden variable models is briefly examined. We also remark on the connection between entanglement and some certain non-commutativity.
Social Impact, a Theoretical Model
Jenny Onyx
2014-01-01
Full Text Available This paper constructs a theoretical model of social impact as it applies to civil society organisations. It does so by drawing on the recent literature on the topic as well as recently completed empirical studies. First, the relationship between impact and evaluation is examined. This is followed by an exploration of the capitals, notably social, human, and cultural capital and their interrelationships, as a theoretical base for the explication of social impact. A formal model of social impact is then identified together with a set of basic principles that may be said to define social impact. Finally the implications of the model are discussed for social policy and organisational management.
Theoretical mechanics for sixth forms
Plumpton, C
1971-01-01
Theoretical Mechanics for Sixth Forms, Second Edition is a 14-chapter book that begins by elucidating the nature of theoretical mechanics. The book then describes the statics of a particle in illustration of the techniques of handling vector quantities. Subsequent chapters focus on the principle of moments, parallel forces and centers of gravity; and the application of Newton's second law to the dynamics of a particle and the ideas of work and energy, impulse and momentum, and power. The concept of friction is also explained. This volume concludes with chapters concerning motion in a circle an
Theoretical chemistry advances and perspectives
Eyring, Henry
1977-01-01
Theoretical Chemistry: Advances and Perspectives, Volume 2 covers all aspects of theoretical chemistry.This book reviews the techniques that have been proven successful in the study of interatomic potentials in order to describe the interactions between complex molecules. The ground state properties of the interacting electron gas when a magnetic field is present are also elaborated, followed by a discussion on the Gellman-Brueckner-Macke theory of the correlation energy that has applications in atomic and molecular systems.This volume considers the instability of the Hartree-Fock ground state
Theoretical Calculation of MMF's Bandwidth
LI Xiao-fu; JIANG De-sheng; YU Hai-hu
2004-01-01
The difference between over-filled launch bandwidth (OFL BW) and restricted mode launch bandwidth (RML BW) is described. A theoretical model is founded to calculate the OFL BW of grade index multimode fiber (GI-MMF),and the result is useful to guide the modification of the manufacturing method.
Theoretical foundations for collaboration engineering
Kolfschoten, G.L.
2007-01-01
Collaboration is often presented as the solution to numerous problems in business and society. However, collaboration is challenging, and collaboration support is not an off-the-shelf-product. This research offers theoretical foundations for Collaboration Engineering. Collaboration Engineering is an
Theoretical Framework for Robustness Evaluation
Sørensen, John Dalsgaard
2011-01-01
This paper presents a theoretical framework for evaluation of robustness of structural systems, incl. bridges and buildings. Typically modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages’. However, althou...
Lightning Talks 2015: Theoretical Division
Shlachter, Jack S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-11-25
This document is a compilation of slides from a number of student presentations given to LANL Theoretical Division members. The subjects cover the range of activities of the Division, including plasma physics, environmental issues, materials research, bacterial resistance to antibiotics, and computational methods.
Theoretical Advanced Study Institute: 2014
DeGrand, Thomas [Univ. of Colorado, Boulder, CO (United States)
2016-08-17
The Theoretical Advanced Study Institute was held at the University of Colorado, Boulder, during June 2-27, 2014. The topic was "Journeys through the Precision Frontier: Amplitudes for Colliders." The organizers were Professors Lance Dixon (SLAC) and Frank Petriello (Northwestern and Argonne). There were fifty one students. Nineteen lecturers gave sixty seventy five minute lectures. A Proceedings was published.
Theoretical Approaches to Political Communication.
Chesebro, James W.
Political communication appears to be emerging as a theoretical and methodological academic area of research within both speech-communication and political science. Five complimentary approaches to political science (Machiavellian, iconic, ritualistic, confirmational, and dramatistic) may be viewed as a series of variations which emphasize the…
Data, Methods, and Theoretical Implications
Hannagan, Rebecca J.; Schneider, Monica C.; Greenlee, Jill S.
2012-01-01
Within the subfields of political psychology and the study of gender, the introduction of new data collection efforts, methodologies, and theoretical approaches are transforming our understandings of these two fields and the places at which they intersect. In this article we present an overview of the research that was presented at a National…
Kumar, Santosh; Sharma, Raj Pal; Venugopalan, Paloth; Witwicki, Maciej; Ferretti, Valeria
2016-11-01
A new hybrid inorganic-organic compound [Cu(Hdien)2(H2O)2](pnb)4·4H2O (1) (where pnb = p-nitrobenzoate), in which the tridentate ligand diethylenetriamine (dien) shows an unusual coordination behavior acting as a bidentate ligand when present in its monoprotonated form (Hdien+) has been synthesized by the reaction of copper(II) p-nitrobenzoate and slight excess of dien in methanol-water mixture (4:1v/v). Re-crystallization of the violet precipitated product from hot water gave single crystals suitable for X-ray diffraction studies. The newly synthesized compound 1 has been characterized by spectroscopic techniques (UV-Vis, FT-IR, EPR), and theoretical methods (DFT and MRCI/SORCI). Single crystal X-ray structure determination revealed the existence of the cationic species [Cu(Hdien)2(H2O)2]4+, four p-nitrobenzoate as counter anions and four water molecules are present as solvent of crystallization. Packing analyses of title compound as well as of the structurally similar [Cu(en)2(H2O)2](pnb)2,2 has shown similarities in the crystalline architecture that both hybrid inorganic-organic compounds is stabilized by various non-covalent interactions such as N-H⋯O, C-H⋯O, O-H⋯O etc.
Quantum mechanics the theoretical minimum
Susskind, Leonard
2014-01-01
From the bestselling author of The Theoretical Minimum, an accessible introduction to the math and science of quantum mechanicsQuantum Mechanics is a (second) book for anyone who wants to learn how to think like a physicist. In this follow-up to the bestselling The Theoretical Minimum, physicist Leonard Susskind and data engineer Art Friedman offer a first course in the theory and associated mathematics of the strange world of quantum mechanics. Quantum Mechanics presents Susskind and Friedman’s crystal-clear explanations of the principles of quantum states, uncertainty and time dependence, entanglement, and particle and wave states, among other topics. An accessible but rigorous introduction to a famously difficult topic, Quantum Mechanics provides a tool kit for amateur scientists to learn physics at their own pace.
Theoretical Provision of Tax Transformation
Feofanova Iryna V.
2016-05-01
Full Text Available The article is aimed at defining the questions, giving answers to which is necessary for scientific substantiation of the tax transformation in Ukraine. The article analyzes the structural-logical relationships of the theories, providing substantiation of tax systems and transformation of them. Various views on the level of both the tax burden and the distribution of the tax burden between big and small business have been systematized. The issues that require theoretical substantiation when choosing a model of tax system have been identified. It is determined that shares of both indirect and direct taxes and their rates can be substantiated by calculations on the basis of statistical data. The results of the presented research can be used to develop the algorithm for theoretical substantiation of tax transformation
Theoretical Advanced Study Institute: 2014
DeGrand, Thomas [Univ. of Colorado, Boulder, CO (United States)
2016-08-17
The Theoretical Advanced Study Institute (TASI) was held at the University of Colorado, Boulder, during June 2-27, 2014. The topic was "Journeys through the Precision Frontier: Amplitudes for Colliders." The organizers were Professors Lance Dixon (SLAC) and Frank Petriello (Northwestern and Argonne). There were fifty-one students. Nineteen lecturers gave sixty seventy-five minute lectures. A Proceedings was published. This TASI was unique for its large emphasis on methods for calculating amplitudes. This was embedded in a program describing recent theoretical and phenomenological developments in particle physics. Topics included introductions to the Standard Model, to QCD (both in a collider context and on the lattice), effective field theories, Higgs physics, neutrino interactions, an introduction to experimental techniques, and cosmology.
Theoretical issues in Spheromak research
Cohen, R. H.; Hooper, E. B.; LoDestro, L. L.; Mattor, N.; Pearlstein, L. D.; Ryutov, D. D.
1997-04-01
This report summarizes the state of theoretical knowledge of several physics issues important to the spheromak. It was prepared as part of the preparation for the Sustained Spheromak Physics Experiment (SSPX), which addresses these goals: energy confinement and the physics which determines it; the physics of transition from a short-pulsed experiment, in which the equilibrium and stability are determined by a conducting wall (``flux conserver``) to one in which the equilibrium is supported by external coils. Physics is examined in this report in four important areas. The status of present theoretical understanding is reviewed, physics which needs to be addressed more fully is identified, and tools which are available or require more development are described. Specifically, the topics include: MHD equilibrium and design, review of MHD stability, spheromak dynamo, and edge plasma in spheromaks.
Theoretical Aspects of Cosmic Acceleration
Trodden, Mark
2016-01-01
Efforts to understand and map the possible explanations for the late time acceleration of the universe have led to a broad range of suggestions, ranging from the cosmological constant and straightforward dark energy, to exotically coupled models, to infrared modifications of General Relativity. If we are to uncover which, if any, of these approaches might provide a serious answer to the problem, it is crucial to understand the constraints that theoretical consistency places on the models, and on the regimes in which they make predictions. In this talk, delivered as an invited plenary lecture at the Dark Side of the Universe conference in Kyoto, Japan, I briefly describe some modern attempts to carry out this program and some of the more interesting ideas that have emerged. As an example, I use the Galileon model, discussing how the Vainshtein mechanism occurs, and how a number of these theoretical problems arise around such backgrounds.
A course in theoretical physics
Shepherd, P J
2013-01-01
This book is a comprehensive account of five extended modules covering the key branches of twentieth-century theoretical physics, taught by the author over a period of three decades to students on bachelor and master university degree courses in both physics and theoretical physics. The modules cover nonrelativistic quantum mechanics, thermal and statistical physics, many-body theory, classical field theory (including special relativity and electromagnetism), and, finally, relativistic quantum mechanics and gauge theories of quark and lepton interactions, all presented in a single, self-contained volume. In a number of universities, much of the material covered (for example, on Einstein’s general theory of relativity, on the BCS theory of superconductivity, and on the Standard Model, including the theory underlying the prediction of the Higgs boson) is taught in postgraduate courses to beginning PhD students. A distinctive feature of the book is that full, step-by-step mathematical proofs of all essentia...
Theoretical Prospects for B Physics
Fleischer, Robert
2015-01-01
The exploration of B-meson decays has reached an unprecedented level of sophistication, with a phase of even much higher precision ahead of us thanks to run 2 of the LHC and the future era of Belle II and the LHCb upgrade. For many processes, the theoretical challenge in the quest to reveal possible footprints of physics beyond the Standard Model will be the control of uncertainties from strong interactions. After a brief discussion of the global picture emerging from the LHC data, I will focus on the theoretical prospects and challenges for benchmark B decays to search for new sources of CP violation, and highlight future opportunities to probe the Standard Model with strongly suppressed rare B decays.
Theoretical Studies of Nanocluster Formation
2016-05-26
5f. WORK UNIT NUMBER Q188 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NO. Air Force Research...For presentation at AFOSR Molecular Dynamics and Theoretical Chemistry Program Review; Arlington, VA (25 May 2016) PA Case Number: #16215; Clearance...Approved for public release; Distribution Unlimited. PA Clearance No: 16215 This briefing contains information up to: 2 Outline 1. Introduction
CONTRACT ASSIGNMENT – THEORETICAL ASPECTS
Bogdan NAZAT
2016-12-01
Full Text Available This project aims to study in detail the theoretical aspects concerning the contract assignment, as provided by the relevant regulation, and the doctrine corresponding to old and current regulations. In this respect, this project aims to give the reader a comprehensive look on the institution in question, the regulation offered by the current Civil Code is reviewed taking into account the national and international doctrine.
ABOUT COMMON AND THEORETICAL INFORMATICS
Andrey A. Mayorov
2015-01-01
Full Text Available In this article are considered the integrant importance of informatics and informational technologys includes the sciences and the humanities.There are a differences between scientifi c grounds of the various information orientations, which include physical informatics, bioinfomatics, technical and social informatics. Creation of a united theoretical base for these orientations is very problematical. The metodologically important issue of classifi cation different informatics is a part of the general informatics, the example of which are considered here.
Theoretical Studies of Silicon Chemistry
1990-02-01
Molecular and Electronic Structure of Silyl Nitrene , M.S. Gordon, Chem. Phys. Lett., 146, 148 (1988). 18. A Theoretical Study of the Three-Membered Rings...phase and crystal structures. Of course, all three possibilities may contribute. B. The Electronic and Molecular Structure of Silyl Nitrene , M.S...a silaimine. An interesting question regarding the primary process is whether the silyl nitrene , R3SiN, is formed as an intermediate. As a first step
Theoretical Studies of Reaction Surfaces
2007-11-02
Similar levels of agreement are being found in studies of water clusters12 , the Menshutkin reaction 13 (ion separation reaction ), a prototypical SN2 ...of both reactants and products. These analyses reveal that Bery pseudorotation occurs repeatedly during the side attack, whereas the SN2 reaction H...31 Aug 97 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS AASERT93 THEORETICAL STUDIES OF REACTION SURFACES F49620-93-1-0556 3484/XS 6. AUTHOR(S) 61103D DR
A New Theoretical Model of a Carbon Nanotube Strain Sensor
QIU Wei; KANG Yi-Lan; LEI Zhen-Kun; QIN Qing-Hua; LI Qiu
2009-01-01
Carbon nanotubes (CNTs) are potential strain sensors due to their excellent mechanical and spectral properties.A new theoretical model of a CNT strain sensor is obtained by applying the polarized Raman properties of CNTs,which calculates the synthetic contributions of Raman spectra from the CNTs in random directions.By using this theoretical model,the analytic relationship between planar strain components and the Raman shift increment of uniformly dispersed CNTs is obtained,which is applicable for accurately characterizing the strain in random directions on the surface of a measured microsystem.
Cryptobiosis: a new theoretical perspective.
Neuman, Yair
2006-10-01
The tardigrade is a microscopic creature that under environmental stress conditions undergoes cryptobiosis [Feofilova, E.P., 2003. Deceleration of vital activity as a universal biochemical mechanism ensuring adaptation of microorganisms to stress factors: A review. Appl. Biochem. Microbiol. 39, 1-18; Nelson, D.R., 2002. Current status of the tardigrada: Evolution and ecology. Integrative Comp. Biol. 42, 652-659]-a temporary metabolic depression-which is considered to be a third state between life and death [Clegg, J.S., 2001. Cryptobiosis-a peculiar state of biological organization. Comp. Biochem. Physiol. Part B 128, 613-624]. In contrast with death, cryptobiosis is a reversible state, and as soon as environmental conditions change, the tardigrade "returns to life." Cryptobiosis in general, and among the tardigrade in particular, is a phenomenon poorly understood [Guppy, M., 2004. The biochemistry of metabolic depression: a history of perceptions. Comp. Biochem. Physiol. Part B 139, 435-442; Schill, R.O., et al., 2004. Stress gene (hsp70) sequences and quantitative expression in Milensium tardigradum (Tardigrade) during active and cryptobiotic stages. J. Exp. Biol. 207, 1607-1613; Watanabe, M., et al., 2002. Mechanisn allowing an insect to survive complete dehydration and extreme temperatures. J. Exp. Biol. 205, 2799-2802; Wright, J.C., 2001. Cryptobiosis 300 years on from van Leuwenhoek: what have we learned about tardigrades? Zool. Anz. 240, 563-582]. Moreover, the ability of the tardigrade to bootstrap itself and to return to life seems paradoxical like the legendary Baron von Munchausen who pulled himself out of the swamp by grabbing his own hair. Two theoretical obstacles prevent us from advancing our knowledge of cryptobiosis. First, we lack appropriate theoretical understanding of reversible processes of biological computation in living systems. Second, we lack appropriate theoretical understanding of bootstrapping in living systems. In this short opinion
INFANTILISM: THEORETICAL CONSTRUCT AND OPERATIONALIZATION
Yelena V. Sabelnikova
2016-01-01
Full Text Available The aim of the presented research is to define and operationalize theoretically the concept of infantilism and its construct. The content of theoretical construct «infantilism» is analyzed. Methods. The methods of theoretical research involve analysis and synthesis. The age and content criteria are analysed in the context of childhood and adulthood. The traits which can be interpreted as adult infantile traits are described. Results. The characteristics of adult infantilism in modern world taking into account the increasing of information flows and socio-economic changes are defined. The definition of the concept «infantilism» including its main features is given. Infantilism is defined as the personal organization including features and models of the previous age period not adequate for the real age stage with emphasis on immaturity of the emotional and volitional sphere. Scientific novelty. The main psychological characteristics of adulthood are described as the reflection, requirement to work and professional activity, existence of professional self-determination, possession of labor skills, need for selfrealization, maturity of the emotional and volitional sphere. As objective adulthood characteristics are considered the following: transition to economic and territorial independence of a parental family, and also development of new social roles, such as a worker, spouse, and parent. Two options of a possible operationalization of concept are allocated: objective (existence / absence in real human life of objective criteria of adulthood and subjective (the self-report on subjective feeling of existence / lack of psychological characteristics of adulthood. Practical significance consists in a construct operationalization of «infantilism» which at the moment has so many interpretations. That operationalization is necessary for the further analysis and carrying out various researches.
Qualitative methods in theoretical physics
Maslov, Dmitrii
2017-01-01
This book comprises a set of tools which allow researchers and students to arrive at a qualitatively correct answer without undertaking lengthy calculations. In general, Qualitative Methods in Theoretical Physics is about combining approximate mathematical methods with fundamental principles of physics: conservation laws and symmetries. Readers will learn how to simplify problems, how to estimate results, and how to apply symmetry arguments and conduct dimensional analysis. A comprehensive problem set is included. The book will appeal to a wide range of students and researchers.
THEORETICAL CONCEPTIONS OF GEOGRAPHY TEACHERS
Eloy Montes Galbán
2007-11-01
Full Text Available The main goal of this research was to determine the current theoretical concepts handled by third stage basic education geography teachers. A non experimental descriptive study was made. Data was collected through a semi structured questionnaire. The population was conformed by the teachers who work at the National schools placed in the parishes Raul Leoni and Cacique Mara of Maracaibo city, Zulia State. There is not clarity in regard to the correct handling of the different geographic currents, and the slight notion teachers have leans towards a traditional, descriptive, retrospective memory based conception.
Theoretical studies of combustion dynamics
Bowman, J.M. [Emory Univ., Atlanta, GA (United States)
1993-12-01
The basic objectives of this research program are to develop and apply theoretical techniques to fundamental dynamical processes of importance in gas-phase combustion. There are two major areas currently supported by this grant. One is reactive scattering of diatom-diatom systems, and the other is the dynamics of complex formation and decay based on L{sup 2} methods. In all of these studies, the authors focus on systems that are of interest experimentally, and for which potential energy surfaces based, at least in part, on ab initio calculations are available.
Interconnection policy: a theoretical survey
César Mattos
2003-01-01
Full Text Available This article surveys the theoretical foundations of interconnection policy. The requirement of an interconnection policy should not be taken for granted in all circumstances, even considering the issue of network externalities. On the other hand, when it is required, an encompassing interconnection policy is usually justified. We provide an overview of the theory on interconnection pricing that results in several different prescriptions depending on which problem the regulator aims to address. We also present a survey on the literature on two-way interconnection.
Machine learning a theoretical approach
Natarajan, Balas K
2014-01-01
This is the first comprehensive introduction to computational learning theory. The author's uniform presentation of fundamental results and their applications offers AI researchers a theoretical perspective on the problems they study. The book presents tools for the analysis of probabilistic models of learning, tools that crisply classify what is and is not efficiently learnable. After a general introduction to Valiant's PAC paradigm and the important notion of the Vapnik-Chervonenkis dimension, the author explores specific topics such as finite automata and neural networks. The presentation
Theoretical studies on kinetics of singlet oxygen in nonthermal plasma
Frolov, Mikhail P.; Ionin, Andrei A.; Kotkov, Andrei A.; Kochetov, Igor V.; Napartovich, Anatolii P.; Podmarkov, Yurii P.; Seleznev, Leonid V.; Sinitsyn, Dmitrii V.; Vagin, Nikolai P.; Yuryshev, Nikolay N.
2004-09-01
An idea to replace singlet delta oxygen (SDO) generator working with wet chemistry by electric discharge generator has got much attention last years. Different kinds of discharge were examined for this purpose, but without a great success. The existing theoretical models are not validated by well-characterized experimental data. To describe complicated kinetics in gas discharge with oxygen one needs to know in detail processes involving numerous electronic excited oxygen molecules and atoms. To gain new knowledge about these processes experimental studies were made on electric discharge properties in gas mixture flow with independent control of inlet SDO concentration. The theoretical model extended to include minor additives like oxygen atoms, water molecules, ozone was developed. Comparison with careful experimental measurements of electric characteristics along with gas composition allows us to verify the model and make theoretical predictions more reliable. Results of numerical simulations using this model for an electron-beam sustained discharge are reported and compared with the experimental data.
The European Theoretical Spectroscopy Facility
Godby, Rex
2007-03-01
The ETSF (www.etsf.eu) is being created as a permanent output of the EU-funded Nanoquanta Network of Excellence (www.nanoquanta.eu, 2004-8), which joins 10 groups and over 100 researchers in research on the theory and simulation of spectroscopy of electrons in matter, and related excited-state electronic properties including quantum transport. The ETSF is intended to contribute significantly to nanoscience and nanotechnology through the development and application of theoretical spectroscopy, involving close collaboration between theorists (the existing Nanoquanta groups together with further theoretical groups) and a new community of experimental and industrial researchers who wish to apply modern theories of spectroscopy. In this talk I shall review some of the scientific output of the project so far, including the development of new ideas and techniques in many-body perturbation theory and time-dependent density-functional theory, and their application to a variety of prototype and actual systems including quantum transport in nanostructures, optical absorption in biological molecules and advanced materials, optical properties of nanoclusters and nanotubes, non-linear optical response, and spectroscopies of complex surfaces. I shall also briefly describe the network's integration activities, including code interoperability and modularity, training of internal and external researchers, and the legal, financial and organizational preparations for the ETSF.
Theoretical approaches to superionic conductivity
C S Sunandana; P Senthil Kumar
2004-02-01
Recent theoretical approaches to the understanding of superionic conductivity in polycrystalline, glassy and polymeric materials are briefly reviewed. Phase transitions to the superionic conducting state in the AgI family are apparently triggered by cluster formation and strong mobile ion interaction within the clusters. Anomalous conductivity and related physical properties are explained in the cluster induced distortion model. Ionic composites such as AgX : Al2O3 ( = Cl, Br and I) involve conducting and non-conducting phases and the all-important interface between the two whose space charge enhances the conductivity and also trigger phase transitions to exotic polymorphic phases, for which the mechanisms are yet to be explored. Ion hopping dynamics controls the conductivity of superionic glasses. Mode coupling and jump relaxation theories account for the non-Debye relaxation observed in a.c. conductivity of these glasses. The theory of conductivity in polymer electrolytes-still in its infancy-involves their complex structure and glass transition behaviour. Preparative and thermal history, composition and crystallinity control ionic conductivity. New approaches to the synthesis of optimal polymer electrolytes such as rubbery electrolytes, crystalline polymers and nanocomposites must be considered before achieving a comprehensive theoretical understanding.
Theoretical perspectives on narrative inquiry.
Emden, C
1998-04-01
Narrative inquiry is gaining momentum in the field of nursing. As a research approach it does not have any single heritage of methodology and its practitioners draw upon diverse sources of influence. Central to all narrative inquiry however, is attention to the potential of stories to give meaning to people's lives, and the treatment of data as stories. This is the first of two papers on the topic and addresses the theoretical influences upon a particular narrative inquiry into nursing scholars and scholarship. The second paper, Conducting a narrative analysis, describes the actual narrative analysis as it was conducted in this same study. Together, the papers provide sufficient detail for others wishing to pursue a similar approach to do so, or to develop the ideas and procedures according to their own way of thinking. Within this first theoretical paper, perspectives from Jerome Bruner (1987) and Wade Roof (1993) are outlined. These relate especially to the notion of stories as 'imaginative constructions' and as 'cultural narratives' and as such, highlight the profound importance of stories as being individually and culturally meaningful. As well, perspectives on narrative inquiry from nursing literature are highlighted. Narrative inquiry in this instance lies within the broader context of phenomenology.
Theoretical perspectives on strange physics
Ellis, J.
1983-04-01
Kaons are heavy enough to have an interesting range of decay modes available to them, and light enough to be produced in sufficient numbers to explore rare modes with satisfying statistics. Kaons and their decays have provided at least two major breakthroughs in our knowledge of fundamental physics. They have revealed to us CP violation, and their lack of flavor-changing neutral interactions warned us to expect charm. In addition, K/sup 0/-anti K/sup 0/ mixing has provided us with one of our most elegant and sensitive laboratories for testing quantum mechanics. There is every reason to expect that future generations of kaon experiments with intense sources would add further to our knowledge of fundamental physics. This talk attempts to set future kaon experiments in a general theoretical context, and indicate how they may bear upon fundamental theoretical issues. A survey of different experiments which would be done with an Intense Medium Energy Source of Strangeness, including rare K decays, probes of the nature of CP isolation, ..mu.. decays, hyperon decays and neutrino physics is given. (WHK)
Insuring against loss of evidence in game-theoretic probability
Dawid, A Philip; Shafer, Glenn; Shen, Alexander; Vereshchagin, Nikolai; Vovk, Vladimir
2010-01-01
We consider the game-theoretic scenario of testing the performance of Forecaster by Sceptic who gambles against the forecasts. Sceptic's current capital is interpreted as the amount of evidence he has found against Forecaster. Reporting the maximum of Sceptic's capital so far exaggerates the evidence. We characterize the set of all increasing functions that remove the exaggeration. This result can be used for insuring against loss of evidence.
THEORETICAL ASPECTS OF FILMMUSIC STUDY
Egorova Tatiana K.
2014-04-01
Full Text Available In this article, author analyzes the theoretical aspects of the film music study taking into account with modern realities in the development of world film-process and attempts to its scientific understanding. Need for innovation in this area is long overdue, because the existing on this topic nonfiction no longer meets the new aesthetic and art-practical achievements and innovations in the film music development at the XXI century. Related to the phenomenon of music in screen arts a number of new terms and concepts require a certain adjustment as well. Their range of action is not yet fully defined. Author of the article offered her version of their content-semantic interpretation (largely experimental designed to promote new research methods for the film music study.
Theoretical motions of hydrofoil systems
Imlay, Frederick H
1948-01-01
Results are presented of an investigation that has been undertaken to develop theoretical methods of treating the motions of hydrofoil systems and to determine some of the important parameters. Variations of parameters include three distributions of area between the hydrofoils, two rates of change of downwash angle with angle of attack, three depths of immersion, two dihedral angles, two rates of change of lift with immersion, three longitudinal hydrofoil spacings, two radii of gyration in pitching, and various horizontal and vertical locations of the center of gravity. Graphs are presented to show locations of the center of gravity for stable motion, values of the stability roots, and motions following the sudden application of a vertical force or a pitching moment to the hydrofoil system for numerous sets of values of the parameters.
Dental Photothermal Radiometry: Theoretical Analysis.
Matvienko, Anna; Jeon, Raymond; Mandelis, Andreas; Abrams, Stephen
2007-03-01
Dental enamel demineralization in its early stages is very difficult to detect with conventional x-rays or visual examination. High-resolution techniques, such as scanning electron microscopy, usually require destruction of the tooth. Photothermal Radiomety (PTR) was recently applied as a safe, non-destructive, and highly sensitive tool for the detection of early dental demineralization, artificially created on the enamel surface. The experiments showed very high sensitivity of the measured signal to incipient changes in the surface structure, emphasizing the clinical capabilities of the method. In order to analyze the biothermophotonic phenomena in a tooth sample during the photothermal excitation, a theoretical model featuring coupled diffuse-photon-density-wave and thermal-wave fields was developed. Numerical simulations identified the effects on the PTR signal of changes in optical and thermal properties of enamel and dentin as a result of demineralization. The model predictions and experimental results will be compared and discussed.
Theoretical physics 1 classical mechanics
Nolting, Wolfgang
2016-01-01
This textbook offers a clear and comprehensive introduction to classical mechanics, one of the core components of undergraduate physics courses. The book starts with a thorough introduction to the mathematical tools needed, to make this textbook self-contained for learning. The second part of the book introduces the mechanics of the free mass point and details conservation principles. The third part expands the previous to mechanics of many particle systems. Finally the mechanics of the rigid body is illustrated with rotational forces, inertia and gyroscope movement. Ideally suited to undergraduate students in their first year, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series...
Theoretical aspects of Chiral Dynamics
Leutwyler, H
2015-01-01
Many of the quantities of interest at the precision frontier in particle physics require a good understanding of the strong interaction at low energies. The present talk reviews the theoretical framework used in this context. In particular, I draw attention to the fact that applications of effective field theory methods in the low energy domain involve two different aspects: dependence of the quantities of interest on the quark masses and dependence on the momenta. While the lattice approach gives an excellent handle on the low energy constants that govern the quark mass dependence, the most efficient tool to pin down the momentum dependence is dispersion theory. At the same time, the dispersive analysis enlarges the energy range where the effective theory applies. In the meson sector, the interplay of the various sources of information has led to a coherent framework that describes the low energy structure at remarkably high resolution. The understanding of the low energy properties in the baryon sector is l...
Particle Interferometry New Theoretical Results
Heinz, Ulrich W
1997-01-01
By measuring hadronic single-particle spectra and two-particle correlations in heavy-ion collisions, the size and dynamical state of the collision fireball at freeze-out can be reconstructed. I discuss the relevant theoretical methods and their limitations. By applying the formalism to recent pion correlation data from Pb+Pb collisions at CERN we demonstrate that the collision zone has undergone strong transverse growth before freeze-out (by a factor 2-3 in each direction), and that it expands both longitudinally and transversally. From the thermal and flow energy density at freeze-out the energy density at the onset of transverse expansion can be estimated from conservation laws. It comfortably exceeds the critical value for the transition to color deconfined matter.
Theoretical information reuse and integration
Rubin, Stuart
2016-01-01
Information Reuse and Integration addresses the efficient extension and creation of knowledge through the exploitation of Kolmogorov complexity in the extraction and application of domain symmetry. Knowledge, which seems to be novel, can more often than not be recast as the image of a sequence of transformations, which yield symmetric knowledge. When the size of those transformations and/or the length of that sequence of transforms exceeds the size of the image, then that image is said to be novel or random. It may also be that the new knowledge is random in that no such sequence of transforms, which produces it exists, or is at least known. The nine chapters comprising this volume incorporate symmetry, reuse, and integration as overt operational procedures or as operations built into the formal representations of data and operators employed. Either way, the aforementioned theoretical underpinnings of information reuse and integration are supported.
Theoretical Models of Generalized Quasispecies.
Wagner, Nathaniel; Atsmon-Raz, Yoav; Ashkenasy, Gonen
2016-01-01
Theoretical modeling of quasispecies has progressed in several directions. In this chapter, we review the works of Emmanuel Tannenbaum, who, together with Eugene Shakhnovich at Harvard University and later with colleagues and students at Ben-Gurion University in Beersheva, implemented one of the more useful approaches, by progressively setting up various formulations for the quasispecies model and solving them analytically. Our review will focus on these papers that have explored new models, assumed the relevant mathematical approximations, and proceeded to analytically solve for the steady-state solutions and run stochastic simulations . When applicable, these models were related to real-life problems and situations, including changing environments, presence of chemical mutagens, evolution of cancer and tumor cells , mutations in Escherichia coli, stem cells , chromosomal instability (CIN), propagation of antibiotic drug resistance , dynamics of bacteria with plasmids , DNA proofreading mechanisms, and more.
Hash Functions and Information Theoretic Security
Bagheri, Nasour; Knudsen, Lars R.; Naderi, Majid; Thomsen, Søren S.
Information theoretic security is an important security notion in cryptography as it provides a true lower bound for attack complexities. However, in practice attacks often have a higher cost than the information theoretic bound. In this paper we study the relationship between information theoretic attack costs and real costs. We show that in the information theoretic model, many well-known and commonly used hash functions such as MD5 and SHA-256 fail to be preimage resistant.
Hash functions and information theoretic security
Bagheri, Nasoor; Knudsen, Lars Ramkilde; Naderi, Majid;
2009-01-01
Information theoretic security is an important security notion in cryptography as it provides a true lower bound for attack complexities. However, in practice attacks often have a higher cost than the information theoretic bound. In this paper we study the relationship between information theoretic...... attack costs and real costs. We show that in the information theoretic model, many well-known and commonly used hash functions such as MD5 and SHA-256 fail to be preimage resistant....
Theoretical Spectra of Terrestrial Exoplanet Surfaces
Hu, Renyu; Seager, Sara
2012-01-01
We investigate spectra of airless rocky exoplanets with a theoretical framework that self-consistently treats reflection and thermal emission. We find that a silicate surface on an exoplanet is spectroscopically detectable via prominent Si-O features in the thermal emission bands of 7 - 13 \\mu m and 15 - 25 \\mu m. The variation of brightness temperature due to the silicate features can be up to 20 K for an airless Earth analog, and the silicate features are wide enough to be distinguished from atmospheric features with relatively high-resolution spectra. The surface characterization thus provides a method to unambiguously identify a rocky exoplanet. Furthermore, identification of specific rocky surface types is possible with the planet's reflectance spectrum in near-infrared broad bands. A key parameter to observe is the difference between K band and J band geometric albedos (A_g (K)-A_g (J)): A_g (K)-A_g (J) > 0.2 indicates that more than half of the planet's surface has abundant mafic minerals, such as oliv...
A Field Theoretic Approach to Roughness Corrections
Wu, Hua Yao
2011-01-01
We develop a systematic field theoretic description for the roughness correction to the Casimir free energy of parallel plates. Roughness is modeled by specifying a generating functional for correlation functions of the height profile, the two-point correlation function being characterized by the variance, \\sigma^2, and correlation length, \\ell, of the profile. We obtain the partition function of a massless scalar quantum field interacting with the height profile of the surface via a \\delta-function potential. The partition function of this model is also given by a holographic reduction to three coupled scalar fields on a two-dimensional plane. The original three-dimensional space with a parallel plate at separation 'a' is encoded in the non-local propagators of the surface fields on its boundary. Feynman rules for this equivalent 2+1-dimensional model are derived and its counter terms constructed. The two-loop contribution to the free energy of this model gives the leading roughness correction. The absolute ...
Theoretical studies of molecular interactions
Lester, W.A. Jr. [Univ. of California, Berkeley (United States)
1993-12-01
This research program is directed at extending fundamental knowledge of atoms and molecules including their electronic structure, mutual interaction, collision dynamics, and interaction with radiation. The approach combines the use of ab initio methods--Hartree-Fock (HF) multiconfiguration HF, configuration interaction, and the recently developed quantum Monte Carlo (MC)--to describe electronic structure, intermolecular interactions, and other properties, with various methods of characterizing inelastic and reaction collision processes, and photodissociation dynamics. Present activity is focused on the development and application of the QMC method, surface catalyzed reactions, and reorientation cross sections.
Theoretical model of ``fuzz'' growth
Krasheninnikov, Sergei; Smirnov, Roman
2012-10-01
Recent more detailed experiments on tungsten irradiation with low energy helium plasma, relevant to the near-wall plasma conditions in magnetic fusion reactor like ITER, demonstrated (e.g. see Ref. 1) a very dramatic change in both surface morphology and near surface material structure of the samples. In particular, it was shown that a long (mm-scale) and thin (nm-scale) fiber-like structures filled with nano-bubbles, so-called ``fuzz,'' start to grow. In this work theoretical model of ``fuzz'' growth [2] describing the main features observed in experiments is presented. This model, based on the assumption of enhancement of creep of tungsten containing significant fraction of helium atoms and clusters. The results of the MD simulations [3] support this idea and demonstrate a strong reduction of the yield strength for all temperature range. They also show that the ``flow'' of tungsten strongly facilitates coagulation of helium clusters and the formation of nano-bubbles.[4pt] [1] M. J. Baldwin, et al., J. Nucl. Mater. 390-391 (2009) 885;[0pt] [2] S. I. Krasheninnikov, Physica Scripta T145 (2011) 014040;[0pt] [3] R. D. Smirnov and S. I. Krasheninnikov, submitted to J. Nucl. Materials.
Climate Change: a Theoretical Review
Muhammad Ishaq-ur Rahman
2013-01-01
Full Text Available Climate Change has been undoubtedly the most illustrious environmental issue since late 20th century. But neither the discourse merely emerged during that time, nor it was problematized in the same way since its onset. History of Climate Change discourse reveals that from a purely scientific concern it has turned into a public agenda that is nowadays more inclined to be development problem. Transformations have brought about a complete new paradigm every time. This article presents a theoretical analysis of the Climate Change discourse and to do so it captured the underlying philosophy of the issue using Thomas Kuhn’s well-known thesis of ‘paradigm shift’. In particular it discusses about the crisis that lead the issue towards transformations; explores key perspectives around the crisis thus representation of the issue in the environmental discourse over the time. While this paper establishes that with the beginning of the 21st century, the discourse entered into a new paradigm and will reach to a critical point by the end of 2012, it finally postulates some measures that the discourse might integrate with the existing to advance beyond that point.
Studies in theoretical particle physics
Kaplan, D.B.
1991-07-01
This proposal focuses on research on three distinct areas of particle physics: (1) Nonperturbative QCD. I tend to continue work on analytic modelling of nonperturbative effects in the strong interactions. I have been investigating the theoretical connection between the nonrelativistic quark model and QCD. The primary motivation has been to understand the experimental observation of nonzero matrix elements involving current strange quarks in ordinary matter -- which in the quark model has no strange quark component. This has led to my present work on understanding constituent (quark model) quarks as collective excitations of QCD degrees of freedom. (2) Weak Scale Baryogenesis. A continuation of work on baryogenesis in the early universe from weak interactions. In particular, an investigation of baryogenesis occurring during the weak phase transition through anomalous baryon violating processes in the standard model of weak interactions. (3) Flavor and Compositeness. Further investigation of a new mechanism that I recently discovered for dynamical mass generation for fermions, which naturally leads to a family hierarchy structure. A discussion of recent past work is found in the next section, followed by an outline of the proposed research. A recent publication from each of these three areas is attached to this proposal.
THEORETICAL ASPECTS OF INNOVATION DEVELOPMENT
Evelina Šakalytė
2013-06-01
Full Text Available Purpose – Innovation is defined as an economic stimulus and the key factor of scientific and technological progress as well as international competitiveness. Therefore it is essential to identify theoretical conceptions and approaches of innovation development and review the use of innovation value chain. Design/methodology/approach – analysis of scientific literature. Findings – Innovation plays a significant role of business growth and is a principal factor of survival in competition and incentive of economic development. The importance of the innovation value chain awareness has been brought out as it significantly contributes to the successful development of innovation. Research limitations/implications – the theory of innovation in manufacturing sector and service sector has not been distinguished enough yet. Practical implications – comprehension of innovation concepts and innovation value chain helps to see multiple connections throughout the entire innovation process: from the beginning to the end. The information gained regarding to the innovation value chain helps managers to focus on innovation as a complete product and strengthen weaknesses. Originality/Value – The topic of innovation was analyzed for few previous decades, however, the decision on the mutual understanding on innovation concept have not been highlighted. The paper reveals the systematic conceptual overview on comprehension of innovation and the importance of innovation development process in today’s fast changing competitive market. Keywords: innovation, innovation value chain, knowledge. Research type: scientific literature review.
Research in Theoretical Particle Physics
Feldman, Hume A; Marfatia, Danny
2014-09-24
This document is the final report on activity supported under DOE Grant Number DE-FG02-13ER42024. The report covers the period July 15, 2013 – March 31, 2014. Faculty supported by the grant during the period were Danny Marfatia (1.0 FTE) and Hume Feldman (1% FTE). The grant partly supported University of Hawaii students, David Yaylali and Keita Fukushima, who are supervised by Jason Kumar. Both students are expected to graduate with Ph.D. degrees in 2014. Yaylali will be joining the University of Arizona theory group in Fall 2014 with a 3-year postdoctoral appointment under Keith Dienes. The group’s research covered topics subsumed under the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. Many theoretical results related to the Standard Model and models of new physics were published during the reporting period. The report contains brief project descriptions in Section 1. Sections 2 and 3 lists published and submitted work, respectively. Sections 4 and 5 summarize group activity including conferences, workshops and professional presentations.
FINANCIAL STABILITY - A THEORETICAL APPROACH
Maria Vasilescu
2012-03-01
Full Text Available Central banks have become poles of stability and decisive factors of globalization. Financialstability represents a national issue, a public asset, that requires both an intervention of public judicious authoritiesand their cooperation with private sector. Given the integration of financial markets during the last decades in bothdeveloped and developing countries, as direct result of globalization, liberalization and deregulation processes, andthe high degree of innovation they felt over time, a shift in market participants’ perceptions on the importance ofstable financial systems in economic growth arose. The global context characterized by the interdependence ofmarkets and institutions, emergence of new techniques and instruments, increasing international capital flowsstressed the new meanings of the analysis of financial stability.
Structure and content of fencers’ theoretical training
Briskin Y.A.
2013-08-01
Full Text Available The structure and content of the theoretical training in the system of long-term improvement of athletes fencers is identified. Found that the theoretical training athletes selected 1.2-2.0% (initial training, 1,9-2,3% (preliminary stage of basic training, 2.1% (stage specialized basic training, 1, 8% (preparation stage for the highest achievements of the total training load in the annual cycle of training. It is established that there is a wrong approach to the planning of educational material on theoretical training. Under it, information material (by category and blocks presented based on the total phase, rather than individual grade levels. Recommended compensation direction of the individual components of theoretical training athletes: refining the means and methods of theoretical training, structuring of information, implementation of control theoretical training.
On image segmentation using information theoretic criteria
Aue, Alexander; 10.1214/11-AOS925
2012-01-01
Image segmentation is a long-studied and important problem in image processing. Different solutions have been proposed, many of which follow the information theoretic paradigm. While these information theoretic segmentation methods often produce excellent empirical results, their theoretical properties are still largely unknown. The main goal of this paper is to conduct a rigorous theoretical study into the statistical consistency properties of such methods. To be more specific, this paper investigates if these methods can accurately recover the true number of segments together with their true boundaries in the image as the number of pixels tends to infinity. Our theoretical results show that both the Bayesian information criterion (BIC) and the minimum description length (MDL) principle can be applied to derive statistically consistent segmentation methods, while the same is not true for the Akaike information criterion (AIC). Numerical experiments were conducted to illustrate and support our theoretical fin...
Toward a Theoretical Framework for Information Science
Amanda Spink
2000-01-01
Information Science is beginning to develop a theoretical framework for the modeling of users interactions with information retrieval (IR) technologies within the more holistic context of human information behavior (Spink, 1998b). This paper addresses the following questions: (1) What is the nature of Information Science? and (2) What theoretical framework and model is most appropriate for Information Science? This paper proposes a theoretical framework for Information Science based on ...
Graph-theoretical matrices in chemistry
Janezic, Dusanka; Nikolic, Sonja; Trinajstic, Nenad
2015-01-01
Graph-Theoretical Matrices in Chemistry presents a systematic survey of graph-theoretical matrices and highlights their potential uses. This comprehensive volume is an updated, extended version of a former bestseller featuring a series of mathematical chemistry monographs. In this edition, nearly 200 graph-theoretical matrices are included.This second edition is organized like the previous one-after an introduction, graph-theoretical matrices are presented in five chapters: The Adjacency Matrix and Related Matrices, Incidence Matrices, The Distance Matrix and Related Matrices, Special Matrices
Engineering graphics theoretical foundations of engineering geometry for design
Brailov, Aleksandr Yurievich
2016-01-01
This professional treatise on engineering graphics emphasizes engineering geometry as the theoretical foundation for communication of design ideas with real world structures and products. It considers each theoretical notion of engineering geometry as a complex solution of direct- and inverse-problems of descriptive geometry and each solution of basic engineering problems presented is accompanied by construction of biunique two- and three-dimension models of geometrical images. The book explains the universal structure of formal algorithms of the solutions of positional, metric, and axonometric problems, as well as the solutions of problems of construction in developing a curvilinear surface. The book further characterizes and explains the added laws of projective connections to facilitate construction of geometrical images in any of eight octants. Laws of projective connections allow constructing the complex drawing of a geometrical image in the American system of measurement and the European system of measu...
Light scattering by particles in water theoretical and experimental foundations
Jonasz, Miroslaw
2007-01-01
Light scattering-based methods are used to characterize small particles suspended in water in a wide range of disciplines ranging from oceanography, through medicine, to industry. The scope and accuracy of these methods steadily increases with the progress in light scattering research. This book focuses on the theoretical and experimental foundations of the study and modeling of light scattering by particles in water and critically evaluates the key constraints of light scattering models. It begins with a brief review of the relevant theoretical fundamentals of the interaction of light with condensed matter, followed by an extended discussion of the basic optical properties of pure water and seawater and the physical principles that explain them. The book continues with a discussion of key optical features of the pure water/seawater and the most common components of natural waters. In order to clarify and put in focus some of the basic physical principles and most important features of the experimental data o...
The truncation of stellar discs A theoretical model
Battaner, E; Jiménez-Vicente, J
1998-01-01
The truncation of stellar discs is not abrupt but characterized by a continuous distancing from the exponential profile. There exists a truncation curve, $t(r)$, ending at a truncation radius, $r_t$. We present here a theoretical model in which it is assumed that the magnetic hypothesis explaining the flat rotation curve also explains the truncation. Once stars are born, the centripetal magnetic force previously acting on the progenitor gas cloud is suddenly interrupted, and stars must move to larger orbits or escape. The agreement between theoretical and observed truncation curves is very satisfactory. Parameters defining the disc gas rotation curve should therefore be related to those defining the truncation. It is predicted that rotation curves that quickly reach the asymptotic value $\\theta_0 = \\theta (r=\\infty)$ would have small truncation radii. On the contrary, $r_t$ and $\\theta_0$ itself, would be uncorrelated quantities.
THEORETICAL SPECTRA OF TERRESTRIAL EXOPLANET SURFACES
Hu Renyu; Seager, Sara [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Ehlmann, Bethany L., E-mail: hury@mit.edu [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States)
2012-06-10
We investigate spectra of airless rocky exoplanets with a theoretical framework that self-consistently treats reflection and thermal emission. We find that a silicate surface on an exoplanet is spectroscopically detectable via prominent Si-O features in the thermal emission bands of 7-13 {mu}m and 15-25 {mu}m. The variation of brightness temperature due to the silicate features can be up to 20 K for an airless Earth analog, and the silicate features are wide enough to be distinguished from atmospheric features with relatively high resolution spectra. The surface characterization thus provides a method to unambiguously identify a rocky exoplanet. Furthermore, identification of specific rocky surface types is possible with the planet's reflectance spectrum in near-infrared broad bands. A key parameter to observe is the difference between K-band and J-band geometric albedos (A{sub g}(K) - A{sub g}(J)): A{sub g}(K) - A{sub g}(J) > 0.2 indicates that more than half of the planet's surface has abundant mafic minerals, such as olivine and pyroxene, in other words primary crust from a magma ocean or high-temperature lavas; A{sub g}(K) - A{sub g}(J) < -0.09 indicates that more than half of the planet's surface is covered or partially covered by water ice or hydrated silicates, implying extant or past water on its surface. Also, surface water ice can be specifically distinguished by an H-band geometric albedo lower than the J-band geometric albedo. The surface features can be distinguished from possible atmospheric features with molecule identification of atmospheric species by transmission spectroscopy. We therefore propose that mid-infrared spectroscopy of exoplanets may detect rocky surfaces, and near-infrared spectrophotometry may identify ultramafic surfaces, hydrated surfaces, and water ice.
Applications of theoretical methods in atmospheric science
Johnson, Matthew Stanley; Goodsite, Michael E.
2008-01-01
Theoretical chemistry involves explaining chemical phenomenon using natural laws. The primary tool of theoretical chemistry is quantum chemistry, and the field may be divided into electronic structure calculations, reaction dynamics and statistical mechanics. These three all play a role in addres...
Beauty baryon decays: a theoretical overview
Wang, Yu-Ming
2014-11-01
I overview the theoretical status and recent progress on the calculations of beauty baryon decays focusing on the QCD aspects of the exclusive semi-leptonic Λb → plμ decay at large recoil and theoretical challenges of radiative and electro-weak penguin decays Λb → Λγ,Λl+l-.
Theoretical derivation of heliostat tracking errors distribution
Badescu, Viorel [Candida Oancea Institute of Solar Energy, Faculty of Mechanical Engineering, Polytechnic University of Bucharest, Spl. Independentei 313, Bucharest 060042 (Romania)
2008-12-15
The tracking error probability distribution is derived on a pure theoretical basis. Methods of integral geometry and geometrical probabilities are used to this purpose. The distribution performs reasonably well when compared with measurements from a small database. The performance of the theoretical distribution is compared with that of other (empirical) probability distributions. The practical relevance of using the present approach is also explained. (author)
A Set Theoretical Approach to Maturity Models
Lasrado, Lester; Vatrapu, Ravi; Andersen, Kim Normann
2016-01-01
Maturity Model research in IS has been criticized for the lack of theoretical grounding, methodological rigor, empirical validations, and ignorance of multiple and non-linear paths to maturity. To address these criticisms, this paper proposes a novel set-theoretical approach to maturity models ch...
. In spite of optimal reaction conditions a complex heterogeneous reactant mixture with a glycerol in oil emulsion occurs. Hence, the movement of material from phase to phase as well as through the catalyst pores becomes important since it can influence the performance of the immobilized enzyme reactor...... and sunflower oil dissolved in a binary tert-butanol:tert-pentanol medium. Practical design-related issues such as required reaction time, enzyme capacity, expansion of the enzyme during wetting, and the effect of different column length-to-diameter ratios, fluid velocities and particle sizes of the enzymes...
Guo, Zheng; Chen, Biqiang; Murillo, Rafael López
2006-01-01
preference to monoglyceride formation. Interestingly the predicted results from COSMO-RS (a quantum chemical model programme) achieved a good agreement with the experimental data, mapping out the specific solvation from the ILs as well as demonstrating the interaction between ILs, substrates and products...
Theoretical aspects of Microwave Frequency Transport in Generic Dimensionality Semiconductors
Prati, Enrico
2002-01-01
The present work can be classified as an investigation for the theoretical study of semiconductors in the microwave (?w) frequency domain. This range owns two properties that let it to be a hot subject for the next years: from one side, there is a basic need of such a characterization to get a satisfactory description of the fundamental solid state physics; from the other side there is the urgent need to analyze and increase performances of technological products in order to improve the quali...
Axiomatic Relation between Thermodynamic and Information-Theoretic Entropies
Weilenmann, Mirjam; Kraemer, Lea; Faist, Philippe; Renner, Renato
2016-12-01
Thermodynamic entropy, as defined by Clausius, characterizes macroscopic observations of a system based on phenomenological quantities such as temperature and heat. In contrast, information-theoretic entropy, introduced by Shannon, is a measure of uncertainty. In this Letter, we connect these two notions of entropy, using an axiomatic framework for thermodynamics [E. H. Lieb and J. Yngvason Proc. R. Soc. 469, 20130408 (2013)]. In particular, we obtain a direct relation between the Clausius entropy and the Shannon entropy, or its generalization to quantum systems, the von Neumann entropy. More generally, we find that entropy measures relevant in nonequilibrium thermodynamics correspond to entropies used in one-shot information theory.
Maracci, Mirko; Cazes, Claire; Vandebrouck, Fabrice; Mariotti, Maria Alessandra
2013-01-01
Mathematics education as a research domain is characterized by a plurality of theoretical approaches. Acknowledging the existence of such diversity and the risks of an excessive theoretical fragmentation does not mean to search for a unifying theory but to urge the community to develop strategies for coping with this diversity. This article is…
The creation in question: a brief cartography of a theoretical course
Tais Rodrigues Dassoler
2011-04-01
Full Text Available This article is the result of discussions produced during a theoretical course aboutcreativity in advertising. Instead of teaching how to create, the proposal of the course was to question what characterizes creation. Departing from this question, the route of a theoretical cartography is presented, trough the deconstruction of the idea of creation, the advertising device is shown in its creative demands. Mobilizing different theoretical perspectives, the text approaches creativity’s myth when problematizes the concept of authorship and presents creation as becomings produced by the very advertising device.
1979-01-01
to motivate the form of the results for inelastic binary collisions characterized by an isotropic scattering cross section. For an inelastic...which are excited or ionized by the e -beam . Strictly speaking , the reverse process for reaction (101. 1) should also be included, although its...ETC F/S 20/5 THEORETICAL MODELING OF MOLECULAR AND ELECTRON KINETIC PROCESS~— efl ~ (rj)JAN 79 W B LACINA NO OO i~—78—C—Ofl9UNCLASSIFIED NRTC—79—7R
International Conference on Theoretical and Computational Physics
2016-01-01
Int'l Conference on Theoretical and Computational Physics (TCP 2016) will be held from August 24 to 26, 2016 in Xi'an, China. This Conference will cover issues on Theoretical and Computational Physics. It dedicates to creating a stage for exchanging the latest research results and sharing the advanced research methods. TCP 2016 will be an important platform for inspiring international and interdisciplinary exchange at the forefront of Theoretical and Computational Physics. The Conference will bring together researchers, engineers, technicians and academicians from all over the world, and we cordially invite you to take this opportunity to join us for academic exchange and visit the ancient city of Xi’an.
Toward a Theoretical Framework for Information Science
Amanda Spink
2000-01-01
Full Text Available Information Science is beginning to develop a theoretical framework for the modeling of users interactions with information retrieval (IR technologies within the more holistic context of human information behavior (Spink, 1998b. This paper addresses the following questions: (1 What is the nature of Information Science? and (2 What theoretical framework and model is most appropriate for Information Science? This paper proposes a theoretical framework for Information Science based on an explication of the processes of human information coordinating behavior and information feedback that facilitate the relationship between human information behavior and human interaction with information retrieval (IR technologies (Web, digital libraries, etc..
Robust recognition via information theoretic learning
He, Ran; Yuan, Xiaotong; Wang, Liang
2014-01-01
This Springer Brief represents a comprehensive review of information theoretic methods for robust recognition. A variety of information theoretic methods have been proffered in the past decade, in a large variety of computer vision applications; this work brings them together, attempts to impart the theory, optimization and usage of information entropy.The?authors?resort to a new information theoretic concept, correntropy, as a robust measure and apply it to solve robust face recognition and object recognition problems. For computational efficiency,?the brief?introduces the additive and multip
Game theoretic approaches for spectrum redistribution
Wu, Fan
2014-01-01
This brief examines issues of spectrum allocation for the limited resources of radio spectrum. It uses a game-theoretic perspective, in which the nodes in the wireless network are rational and always pursue their own objectives. It provides a systematic study of the approaches that can guarantee the system's convergence at an equilibrium state, in which the system performance is optimal or sub-optimal. The author provides a short tutorial on game theory, explains game-theoretic channel allocation in clique and in multi-hop wireless networks and explores challenges in designing game-theoretic m
Information-theoretic resolution of perceptual WSS watermarking of non i.i.d. Gaussian signals
Pateux, Stéphane; Guillemot, Christine
2008-01-01
The theoretical foundations of data hiding have been revealed by formulating the problem as message communication over a noisy channel. We revisit the problem in light of a more general characterization of the watermark channel and of weighted distortion measures. Considering spread spectrum based information hiding, we release the usual assumption of an i.i.d. cover signal. The game-theoretic resolution of the problem reveals a generalized characterization of optimum attacks. The paper then derives closed-form expressions for the different parameters exhibiting a practical embedding and extraction technique.
Theoretical linguistics and its practical application
Olga Ershova
2013-04-01
Full Text Available This article discusses the case of improper use of these theoretical linguistics as applied to the task of the Russian language in the manuals for the preparation of a unified state exam
THEORETICAL AND ORGANIZATIONAL CONDITIONS OF TAX MANAGEMENT
Romanyuk, M.
2008-01-01
The essence of tax managment as the managerial category is observed, the main parts of organizational process of taxation is substantiated, theoretical and organizational conditions of tax management are investigated.
Set-theoretic methods in control
Blanchini, Franco
2015-01-01
The second edition of this monograph describes the set-theoretic approach for the control and analysis of dynamic systems, both from a theoretical and practical standpoint. This approach is linked to fundamental control problems, such as Lyapunov stability analysis and stabilization, optimal control, control under constraints, persistent disturbance rejection, and uncertain systems analysis and synthesis. Completely self-contained, this book provides a solid foundation of mathematical techniques and applications, extensive references to the relevant literature, and numerous avenues for further theoretical study. All the material from the first edition has been updated to reflect the most recent developments in the field, and a new chapter on switching systems has been added. Each chapter contains examples, case studies, and exercises to allow for a better understanding of theoretical concepts by practical application. The mathematical language is kept to the minimum level necessary for the adequate for...
A theoretical approach to measuring pilot workload
Kantowitz, B. H.
1984-01-01
Theoretical assumptions used by researchers in the area of attention, with emphasis upon errors and inconsistent assumptions used by some researchers were studied. Two GAT experiments, two laboratory studies and one field experiment were conducted.
Theoretical clarity is not “Manicheanism”
Hjørland, Birger
2011-01-01
It is argued that in order to establish a new theoretical approach to information science it is necessary to express disagreement with some established views. The “social turn” in information science is not just exemplified in relation to the works of Marcia Bates but in relation to many different...... researchers in the field. Therefore it should not be taken personally, and the debate should focus on the substance. Marcia Bates has contributed considerably to information science. In spite of this some of her theoretical points of departure may be challenged. It is important to seek theoretical clarity...... and this may involve a degree of schematic confrontation that should not be confused with theoretical one-sidedness, “Manicheanism” or lack of respect....
Unified Hybrid Network Theoretical Model Trilogy
无
2011-01-01
The first of the unified hybrid network theoretical model trilogy (UHNTF) is the harmonious unification hybrid preferential model (HUHPM), seen in the inner loop of Fig. 1, the unified hybrid ratio is defined.
Studies In Theoretical High Energy Particle Physics
Keung, Wai Yee [Univ. of Illinois, Chicago, IL (United States)
2017-07-01
This is a final technical report for grant no. DE-SC0007948 describing research activities in theoretical high energy physics at University of Illinois at Chicago for the whole grant period from July 1, 2012 to March 31, 2017.
Eighteenth annual West Coast theoretical chemistry conference
NONE
1997-05-01
Abstracts are presented from the eighteenth annual west coast theoretical chemistry conference. Topics include molecular simulations; quasiclassical simulations of reactions; photodissociation reactions; molecular dynamics;interface studies; electronic structure; and semiclassical methods of reactive systems.
Theoretical chemistry periodicities in chemistry and biology
Eyring, Henry
1978-01-01
Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin
Resistance and Renewal in Theoretical Psychology
. The diversity and creativity of the work undertaken within theoretical psychology is further exemplified by papers on the history of the ISTP and theoretical psychology, a new paradigm for functional disorders, experimental introspection and techniques of self, the performativity of psychological science...... care in refugee family life, resilience thinking in disaster research and practices, resisting quality management in higher education, the relationality and reflexivity of resistance and renewal, research on psychological science from its borders, rethinking possible selves research, imagination...
English for Science and Technology - Theoretical Part
Mousten, Birthe
The books covers the most basic, theoretical approaches to English for Science and Technology. The book is aimed at BA Students or as an introduction to English in the genres of science and technology writing.......The books covers the most basic, theoretical approaches to English for Science and Technology. The book is aimed at BA Students or as an introduction to English in the genres of science and technology writing....
Recent theoretical, neural, and clinical advances in sustained attention research.
Fortenbaugh, Francesca C; DeGutis, Joseph; Esterman, Michael
2017-05-01
Models of attention often distinguish among attention subtypes, with classic models separating orienting, switching, and sustaining functions. Compared with other forms of attention, the neurophysiological basis of sustaining attention has received far less notice, yet it is known that momentary failures of sustained attention can have far-ranging negative effects in healthy individuals, and lasting sustained attention deficits are pervasive in clinical populations. In recent years, however, there has been increased interest in characterizing moment-to-moment fluctuations in sustained attention, in addition to the overall vigilance decrement, and understanding how these neurocognitive systems change over the life span and across various clinical populations. The use of novel neuroimaging paradigms and statistical approaches has allowed for better characterization of the neural networks supporting sustained attention and has highlighted dynamic interactions within and across multiple distributed networks that predict behavioral performance. These advances have also provided potential biomarkers to identify individuals with sustained attention deficits. These findings have led to new theoretical models explaining why sustaining focused attention is a challenge for individuals and form the basis for the next generation of sustained attention research, which seeks to accurately diagnose and develop theoretically driven treatments for sustained attention deficits that affect a variety of clinical populations. © 2017 New York Academy of Sciences.
Demystifying Theoretical Sampling in Grounded Theory Research
Jenna Breckenridge BSc(Hons,Ph.D.Candidate
2009-06-01
Full Text Available Theoretical sampling is a central tenet of classic grounded theory and is essential to the development and refinement of a theory that is ‘grounded’ in data. While many authors appear to share concurrent definitions of theoretical sampling, the ways in which the process is actually executed remain largely elusive and inconsistent. As such, employing and describing the theoretical sampling process can present a particular challenge to novice researchers embarking upon their first grounded theory study. This article has been written in response to the challenges faced by the first author whilst writing a grounded theory proposal. It is intended to clarify theoretical sampling for new grounded theory researchers, offering some insight into the practicalities of selecting and employing a theoretical sampling strategy. It demonstrates that the credibility of a theory cannot be dissociated from the process by which it has been generated and seeks to encourage and challenge researchers to approach theoretical sampling in a way that is apposite to the core principles of the classic grounded theory methodology.
Overview. Department of Theoretical Physics. Section 4
Kwiecinski, J. [Institute of Nuclear Physics, Cracow (Poland)
1995-12-31
Research activity of the Department of the Theoretical Physics spans a wide variety of problems in theoretical high-energy and elementary particle physics, theoretical nuclear physics, theory of the nuclear matter, quark gluon plasma and relativistic heavy-ion collisions, theoretical astrophysics, as well as general physics. Theoretical research in high energy and elementary particle physics is concentrated on the theory of deep inelastic lepton scattering in the region of low x and its phenomenological implication for the ep collider HERA at DESY, on the theory of nonleptonic decays of hadrons, and on low energy {pi}{pi} and K-anti-K interactions and scalar meson spectroscopy. The activity in the theory of relativistic heavy-ion collisions is focused on the study of quark condensate fluctuations, on the analysis of critical scattering near the chiral phase transition, and on Bose-Einstein correlation in heavy-ion collisions. Theoretical studies in nuclear physics and in theory of nuclear matter concern analysis of models, with dynamical symmetry based on group S{sub p}(6,R) for the description of collective modes of atomic nuclei, analysis of the Goldstone bosons in nuclear matter and analysis of saturation properties of nuclear matter. Research in theoretical astrophysics is mainly devoted to the analysis of magnetic properties of hadronic matter in neutron stars with proton admixture. Studies in general physics concern problem related to the Galilean covariance of classical and quantum mechanics. The detailed results obtained in various fields are summarised in presented abstracts as well as information about employed personnel, publications, contribution to conferences, reports, workshops and seminars.
Towards general information theoretical representations of database problems
Joslyn, C.
1997-06-01
General database systems are described from the General Systems Theoretical (GST) framework. In this context traditional information theoretical (statistical) and general information theoretical (fuzzy measure and set theoretical, possibilistic, and random set theoretical) representations are derived. A preliminary formal framework is introduced.
Srivastava, Sangeeta; Gupta, Preeti; Singh, Ranvijay Pratap; Jafri, Asif; Arshad, M.; Banerjee, Monisha
2017-08-01
In the present work 4-(1E,3Z,6E)-3-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-5-oxohepta-1,3,6-trien-1-yl)-2-methoxyphenyl 4-nitrobenzoate (2), a novel curcumin ester was synthesized. The molecular structure and spectroscopic analysis were performed using experimental techniques like FT-IR, 1H,13C NMR, mass and UV-visible as well as theoretical calculations. The theoretical calculations were done by DFT level of theory using B3LYP/6-31G (d,p) basis set. The vibrational wavenumbers were calculated using DFT method and assigned with the help of potential energy distribution (PED). The electronic properties such as frontier orbitals and band gap energies have been calculated using time dependent density functional theory (TD-DFT). The strength and nature of weak intramolecular interactions have been studied by AIM approach. Global and local reactivity descriptors have been computed to predict reactivity and reactive sites in the molecule. First hyperpolarizability values have been calculated to describe the nonlinear optical (NLO) property of the synthesized compounds. Molecular electrostatic potential (MEP) analysis has also been carried out. The anti-hepatic cancer activity of compound 2 was also carried out.
Modelling and characterization of colliding-pulse mode-locked (CPM) quantum well lasers. [MPS1
Bischoff, Svend; Brorson, S.D.; Franck, T.
1996-01-01
A theoretical and experimental study of passive colliding pulse mode-locked quantum well lasers is presented. The theoretical model for the gain dynamics is based on semi-classical density matrixequations. The gain dynamics are characterized exp...
Modelling and characterization of colliding-pulse mode-locked (CPM) quantum well lasers. [MPS1
Bischoff, Svend; Brorson, S.D.; Franck, T.;
1996-01-01
A theoretical and experimental study of passive colliding pulse mode-locked quantum well lasers is presented. The theoretical model for the gain dynamics is based on semi-classical density matrixequations. The gain dynamics are characterized exp...
Poel, Mike van der; Gehrig, Edeltraud; Hess, Ortwin;
2005-01-01
Ultrafast gain dynamics in an optical amplifier with an active layer of self-organized quantum dots (QDs) emitting near 1.3$muhbox m$is characterized experimentally in a pump-probe experiment and modeled theoretically on the basis of QD Maxwell–Bloch equations. Experiment and theory are in good...
Haller, Michel; Cruickshank, Chynthia; Streicher, Wolfgang;
2009-01-01
This paper reviews different methods that have been proposed to characterize thermal stratification in energy storages from a theoretical point of view. Specifically, this paper focuses on the methods that can be used to determine the ability of a storage to promote and maintain stratification...
Sumetsky, M
2010-01-01
High Q-factor localized conical modes are discovered theoretically and demonstrated experimentally in an optical fiber. The theory of these modes provides a means for exceptionally accurate local characterization of the optical fiber nonuniformity and a new paradigm in the field of high Q-factor resonators.
Basic theoretical physics a concise overview
Krey, Uwe
2007-01-01
This concise treatment embraces, in four parts, all the main aspects of theoretical physics (I . Mechanics and Basic Relativity, II. Electrodynamics and Aspects of Optics, III. Non-relativistic Quantum Mechanics, IV. Thermodynamics and Statistical Physics). It summarizes the material that every graduate student, physicist working in industry, or physics teacher should master during his or her degree course. It thus serves both as an excellent revision and preparation tool, and as a convenient reference source, covering the whole of theoretical physics. It may also be successfully employed to deepen its readers' insight and add new dimensions to their understanding of these fundamental concepts. Recent topics such as holography and quantum cryptography are included, thus making this a unique contribution to the learning material for theoretical physics.
Theoretical modeling of electromagnetically imploded plasma liners
Roderick, N.F.; Kohn, B.J.; McCullough, W.F.; Beason, C.W.; Lupo, J.A.; Letterio, J.D. (Air Force Weapons Lab., Kirtland AFB, NM (USA)); Kloc, D.A. (Air Force Academy, CO (USA)); Hussey, T.W. (Sandia National Labs., Albuquerque, NM (USA))
1983-05-01
The generation of high-energy-density plasmas by the electromagnetic implosion of cylindrical foils is explored analytically and through numerical simulation. Theoretical investigations have been performed for a variety of foil initial conditions for both capacitive and inductive pulsed power systems. The development of the theoretical modeling techniques is presented, covering both circuit models and plasma load models. Results from a series of configurations are given, showing the development of modelling techniques used to study the dynamics of the plasma implosion process and the role of instabilities. Interaction between analytic techniques and detailed numerical simulation has led to improvement in all theoretical modeling techniques presently used to study the implosion process. Comparisons of implosion times, shell structure, instability growth rates, and thermalization times have shown good agreement between analytic/heuristic techniques and more detailed two dimensional magnetohydrodynamic simulations. These in turn have provided excellent agreement with experimental results for both capacitor and inductor pulse power systems.
The theoretical foundations of quantum mechanics
Baaquie, Belal E
2013-01-01
The Theoretical Foundations of Quantum Mechanics addresses fundamental issues that are not discussed in most books on quantum mechanics. This book focuses on analyzing the underlying principles of quantum mechanics and explaining the conceptual and theoretical underpinning of quantum mechanics. In particular, the concepts of quantum indeterminacy, quantum measurement and quantum superposition are analyzed to clarify the concepts that are implicit in the formulation of quantum mechanics. The Schrodinger equation is never solved in the book. Rather, the discussion on the fundamentals of quantum mechanics is treated in a rigorous manner based on the mathematics of quantum mechanics. The new concept of the interplay of empirical and trans-empirical constructs in quantum mechanics is introduced to clarify the foundations of quantum mechanics and to explain the counter-intuitive construction of nature in quantum mechanics. The Theoretical Foundations of Quantum Mechanics is aimed at the advanced undergraduate and a...
Information theoretic approach for accounting classification
Ribeiro, E M S
2014-01-01
In this paper we consider an information theoretic approach for the accounting classification process. We propose a matrix formalism and an algorithm for calculations of information theoretic measures associated to accounting classification. The formalism may be useful for further generalizations, and computer based implementation. Information theoretic measures, mutual information and symmetric uncertainty, were evaluated for daily transactions recorded in the chart of accounts of a small company during two years. Variation in the information measures due the aggregation of data in the process of accounting classification is observed. In particular, the symmetric uncertainty seems to be a useful parameter for comparing companies over time or in different sectors; or different accounting choices and standards.
An Order-Theoretic Quantification of Contextuality
Ian T. Durham
2014-09-01
Full Text Available In this essay, I develop order-theoretic notions of determinism and contextuality on domains and topoi. In the process, I develop a method for quantifying contextuality and show that the order-theoretic sense of contextuality is analogous to the sense embodied in the topos-theoretic statement of the Kochen–Specker theorem. Additionally, I argue that this leads to a relation between the entropy associated with measurements on quantum systems and the second law of thermodynamics. The idea that the second law has its origin in the ordering of quantum states and processes dates to at least 1958 and possibly earlier. The suggestion that the mechanism behind this relation is contextuality, is made here for the first time.
Theoretical foundations of electron spin resonance
Harriman, John E
2013-01-01
Theoretical Foundations of Electron Spin Resonance deals with the theoretical approach to electron paramagnetic resonance. The book discusses electron spin resonance in applications related to polyatomic, probably organic, free radicals in condensed phases. The book also focuses on essentially static phenomena, that is, the description and determination of stationary-state energy levels. The author reviews the Dirac theory of the electron in which a four-component wave function is responsible for the behavior of the electron. The author then connects this theory with the nonrelativistic wave f
Bilingualism: theoretical perspectives of language diversity.
Stobbart, C L
1992-01-01
Bilingualism and second language acquisition are discussed with reference to different theoretical perspectives. An integrated definition of bilingualism is provided and concepts underlying second language acquisition are presented. Theoretical perspectives according to Dodson (1985), Skinner (1985) and Krashen (1982) are explored. It is concluded that due to the diverse nature of bilingualism, a single universal theory of second language acquisition does not seem feasible. The need for an increased awareness of the complexity of bilingualism and second language acquisition, particularly within the multicultural and multilingual South African context, is highlighted.
Theoretical studies of chemical reaction dynamics
Schatz, G.C. [Argonne National Laboratory, IL (United States)
1993-12-01
This collaborative program with the Theoretical Chemistry Group at Argonne involves theoretical studies of gas phase chemical reactions and related energy transfer and photodissociation processes. Many of the reactions studied are of direct relevance to combustion; others are selected they provide important examples of special dynamical processes, or are of relevance to experimental measurements. Both classical trajectory and quantum reactive scattering methods are used for these studies, and the types of information determined range from thermal rate constants to state to state differential cross sections.
A Theoretical Framework for Ecological Interface Design
Vicente, Kim J.; Rasmussen, Jens
1988-01-01
A theoretical framework for designing interfaces for complex systems is de-scribed. The framework, called ecological interface design (EID), suggests a set of principles for designing interfaces in a way that supports the funda-mental properties of human cognition. The basis of EID is the skills...... of the task require. The EID approach extends the concept of direct manipulation inter-faces by taking into account the added complications introduced by complex systems. In this paper, we describe the development of the framework, its theoretical foundations, and examples of its application to various work...
Theoretical ecology as etiological from the start.
Donhauser, Justin
2016-12-01
The world's leading environmental advisory institutions look to ecological theory and research as an objective guide for policy and resource management decision-making. In addition to the theoretical and broadly philosophical merits of doing so, it is therefore practically significant to clear up confusions about ecology's conceptual foundations and to clarify the basic workings of inferential methods used in the science. Through discussion of key moments in the genesis of the theoretical branch of ecology, this essay elucidates a general heuristic role of teleological metaphors in ecological research and defuses certain enduring confusions about work in ecology. Copyright © 2016. Published by Elsevier Ltd.
Theoretical solid state physics, v.2
Haug, Albert
2013-01-01
Theoretical Solid State Physics, Volume 2 deals with the electron-lattice interaction and the effect of lattice imperfections. Conductivity, semiconductors, and luminescence are discussed, with emphasis on the basic physical problems and the various phenomena derived from them. The theoretical basis of interaction between electrons and lattices is considered, along with basic concepts of conduction theory, scattering of electrons by imperfections, and radiationless transitions. This volume is comprised of 19 chapters and begins with an overview of the coupling of electrons and the crystal latt
Unitary pattern: a review of theoretical literature.
Musker, Kathleen M
2012-07-01
It is the purpose of this article to illuminate the phenomenon of unitary pattern through a review of theoretical literature. Unitary pattern is a phenomenon of significance to the discipline of nursing because it is manifested in and informs all person-environment health experiences. Unitary pattern was illuminated by: addressing the barriers to understanding the phenomenon, presenting a definition of unitary pattern, and exploring Eastern and Western theoretical literature which address unitary pattern in a way that is congruent with the definition presented. This illumination of unitary pattern will expand nursing knowledge and contribute to the discipline of nursing.
[Holism in theoretical models of nursing].
Neto, D L; da Nóbrega, M M
1999-01-01
In this bibliographical analysis, we present the classification of nine theoretical nursing models which frame holistic thinking according to the school of thought of Human Needs, Interaction and Outcome. It further describes the definition of holism, health, client and nursing in the holistic conception, with the objective of portraying holism in the theoretical references of nursing: The Ambiental Theory of Nightingale, the Interpersonal Theory of Peplau, the Philosophical Theory of Hall, The Theory of Basics Principals of Henderson, the Theory of Self Care of Orem, the Prescriptive Theory of Wiedenbach, the Theory of Basic Needs of Horta, the Theory of Adaptation of Roy and the Theory of Holism of Levine.
Theoretical and quantum mechanics fundamentals for chemists
Ivanov, Stefan
2006-01-01
Provides the basics of theoretical and quantum mechanics in one place and emphasizes the continuity between themUniquely presented to be used for self-taught courses covering theoretical and quantum mechanicsEach chapter includes a detailed outline, a summary, self-assessment questions for which answers can be found in the textInvaluable for chemistry undergraduate and graduate students, chemists, other non-physical scientists, engineering students of modern techniques and technology, specialists who need a better understanding of quantum mechanics.
Socio-theoretic Accounts of IS
Rose, Jeremy; Jones, Matthew
2005-01-01
A long-standing debate in the IS literature concerns the relationship between technology and organization. Does technology cause effects in organizations, or is it humans that determine how technology is used? Many socio-theoretic accounts of a middle way between the extremes of technological...... be studied through ERP systems. These systems, though built and implemented by people, are thought to be wide-ranging in their effects on organizations, and offer good opportunities for the study of the interplay of human and machine agency. However these empirical stories also reflect the theoretical...
Elements of theoretical mechanics for electronic engineers
Bultot, Franz
1965-01-01
Elements of Theoretical Mechanics for Electronic Engineers deals with theoretical mechanics, which is considered one of the fundamental branches of instruction essential to training an engineer. This book discusses the oscillatory motions and their counterparts in electrical circuits and radio, and provides an introduction to differential operators of vector field theory. Other topics covered include systems and functions of vectors; dynamics of a free point; vibrations and waves; and statics. Worked examples and many notes on the application of most sections of the theories to electrical deve
GAO Jian's Theoretical Thoughts in Translation
区沛仪
2016-01-01
As an experienced translator and theorist, GAO Jian has translated numerous English works into Chinese and pub-lished a series of theoretical thoughts concerning the most fundamental problems in translation studies. He has formed a unique style in translation and proposed some theoretical concepts with great expertise. Gao represents the translators'spirit of the time. His theories are highly comprehensive and pragmatic. His discussion of translatability of style, relativity and the Language Characteristics Theory reflect the academic thinking among translators in China, which inspires many young translators and the-orists.
Photography and History: methodological and theoretical issues
Ivo Santos Canabarro
2015-06-01
Full Text Available This article discusses issues related to the relation of photography with the construction of historical knowledge, realizing the theoretical dimensions that encompass a whole field of study about photography. The use of photography with its theoretical and methodological support in history is very recent, as many historians only used it for writing text illustration. Our hypothesis is that photography can be an object and source of investigation and, at the same time, an object that offers notions of its use as a specific problem in the field of visual culture.
Biology is more theoretical than physics.
Gunawardena, Jeremy
2013-06-01
The word "theory" is used in at least two senses--to denote a body of widely accepted laws or principles, as in "Darwinian theory" or "quantum theory," and to suggest a speculative hypothesis, often relying on mathematical analysis, that has not been experimentally confirmed. It is often said that there is no place for the second kind of theory in biology and that biology is not theoretical but based on interpretation of data. Here, ideas from a previous essay are expanded upon to suggest, to the contrary, that the second kind of theory has always played a critical role and that biology, therefore, is a good deal more theoretical than physics.
Theoretical Perspectives on the Internationalization of Firms
Rask, Morten; Håkonsson, Dorthe Døjbak; Strandskov, Jesper
2008-01-01
The purpose of this article is to build a coherent framework of the four main theories relating to the internationalization of firms, in order to facilitate better business teaching and research. Yet, theories of the internationalization of firms are broad and rest on different underlying...... assumptions. With the purpose of clarifying the potential for integration of partial theories and fragments in a more logically connected theoretical area, this article offers a meta-theoretical overview of four perspectives within international business economics: Research and its related background, basic...
Ultrasonic materials characterization
Smith, R. L.
1987-02-01
The National NDT Center at Harwell has been developing methods for the characterization of materials using ultrasonics. This paper reviews the progress made in applying ultrasonic attenuation measurements to the determination of such quantities as grain size and dislocation content. A method, ultrasonic attenuation spectral analysis, has been developed, which enables the contributions of scattering and absorption to the total attenuation to be separated. The theoretical advances that have been made are also described. Some of the practical applications of the technique are illustrated and future development discussed.
Field theoretic simulations of the interfacial properties of complex coacervates
Riggleman, Robert; Fredrickson, Glenn
2011-03-01
Many biological processes and emerging technologies, such as wet adhesives and biosensors, rely on the association between oppositely charged polyelectrolytes. Such association is driven not only by the electrostatic interactions between the polyelectrolytes, but there is also a substantial entropy gain associated with counterion release upon complexation. In some cases, the association between oppositely charged polymers can lead to a solid precipitate while others can result in a fluid phase rich in polyelectrolytes (coacervate phase) coexisting with a polyelectrolyte-dilute solvent phase. For many of the applications seeking to exploit coacervation, characterization of the interface between the solvent phase and the coacervate is of paramount importance. In this talk, we will present the results of field-theoretic simulations for a coarse-grained polyelectrolyte model that exhibits complex coacervation. Our simulations sample the fully-fluctuating fields in three-dimensions and provide a detailed characterization of the interface between the solvent and the coacervate phase for symmetric polyelectrolytes (where both the polycations and the polyanions carry identical charge densities) as a function of salt concentration and strength of the electrostatic fields. Finally, we characterize the interfacial properties for a select set of asymmetric conditions.
Xiao, Manlin; Zhang, Jianglin
2016-01-01
The phenomenon that engineering students have little interest in theoretical knowledge learning is more and more apparent. Therefore, most students fail to understand and apply theories to solve practical problems. To solve this problem, the importance of improving students' interest in the learning theoretical course is discussed firstly in this…
Dagiuklas Tasos
2011-01-01
Full Text Available This paper presents a Wireless Information-Theoretic Security (WITS scheme, which has been recently introduced as a robust physical layer-based security solution, especially for infrastructureless networks. An autonomic network of moving users was implemented via 802.11n nodes of an ad hoc network for an outdoor topology with obstacles. Obstructed-Line-of-Sight (OLOS and Non-Line-of-Sight (NLOS propagation scenarios were examined. Low-speed user movement was considered, so that Doppler spread could be discarded. A transmitter and a legitimate receiver exchanged information in the presence of a moving eavesdropper. Average Signal-to-Noise Ratio (SNR values were acquired for both the main and the wiretap channel, and the Probability of Nonzero Secrecy Capacity was calculated based on theoretical formula. Experimental results validate theoretical findings stressing the importance of user location and mobility schemes on the robustness of Wireless Information-Theoretic Security and call for further theoretical analysis.
A theoretical model of multielectrode DBR lasers
Pan, Xing; Olesen, Henning; Tromborg, Bjarne
1988-01-01
A theoretical model for two- and three-section tunable distributed Bragg reflector (DBR) lasers is presented. The static tuning properties are studied in terms of threshold current, linewidth, oscillation frequency, and output power. Regions of continuous tuning for three-section DBR lasers...
Theoretical Foundations for Website Design Courses.
Walker, Kristin
2002-01-01
Considers how theoretical foundations in website design courses can facilitate students learning the genres of Internet communication. Proposes ways that theories can be integrated into website design courses. Focuses on two students' website portfolios and ways they utilize genre theory and activity theory discussed in class to produce websites…
Higgs boson couplings: measurements and theoretical interpretation
Mariotti, Chiara
2016-01-01
This report will review the Higgs boson properties: the mass, the total width and the couplings to fermions and bosons. The measurements have been performed with the data collected in 2011 and 2012 at the LHC accelerator at CERN by the ATLAS and CMS experiments. Theoretical frameworks to search for new physics are also introduced and discussed.
Some experimental aspects of optimality theoretic pragmatics
Blutner, R.; Németh T., E.; Bibok, K.
2010-01-01
The article has three main concerns: (i) it gives a concise introduction into optimality-theoretic pragmatics; (ii) it discusses the relation to alternative accounts (relevance theory and Levinson's theory of presumptive meanings); (iii) it reviews recent findings concerning the psychological realit
Assessing Two Theoretical Frameworks of Civic Engagement
García-Cabrero, Benilde; Pérez-Martínez, María Guadalupe; Sandoval-Hernández, Andrés; Caso-Niebla, Joaquín; Díaz-López, Carlos David
2016-01-01
The purpose of this study was to empirically test two major theoretical models: a modified version of the social capital model (Pattie, Seyd and Whiteley, 2003), and the Informed Social Engagement Model (Barr and Selman, 2014; Selman and Kwok, 2010), to explain civic participation and civic knowledge of adolescents from Chile, Colombia and Mexico,…
An e-Learning Theoretical Framework
Aparicio, Manuela; Bacao, Fernando; Oliveira, Tiago
2016-01-01
E-learning systems have witnessed a usage and research increase in the past decade. This article presents the e-learning concepts ecosystem. It summarizes the various scopes on e-learning studies. Here we propose an e-learning theoretical framework. This theory framework is based upon three principal dimensions: users, technology, and services…
Child Language Acquisition: Contrasting Theoretical Approaches
Ambridge, Ben; Lieven, Elena V. M.
2011-01-01
Is children's language acquisition based on innate linguistic structures or built from cognitive and communicative skills? This book summarises the major theoretical debates in all of the core domains of child language acquisition research (phonology, word-learning, inflectional morphology, syntax and binding) and includes a complete introduction…
Theoretical Issues of the Constitutional Regulation Mechanism
Zhussupova, Guldaray B.; Zhailyaubayev, Rassul T.; Ukin, Symbat K.; Shunayeva, Sylu M.; Nurmagambetov, Rachit G.
2016-01-01
The purpose of this research is to define the concept of "constitutional regulation mechanism." The definition of the concept of "constitutional regulation mechanism" will give jurists and legislators a theoretical framework for developing legal sciences, such as the constitutional law and the theory of state and law. The…
Why Network? Theoretical Perspectives on Networking
Muijs, Daniel; West, Mel; Ainscow, Mel
2010-01-01
In recent years, networking and collaboration have become increasingly popular in education. However, there is at present a lack of attention to the theoretical basis of networking, which could illuminate when and when not to network and under what conditions networks are likely to be successful. In this paper, we will attempt to sketch the…
CO oxidation on gold nanoparticles: Theoretical studies
Remediakis, Ioannis; Lopez, Nuria; Nørskov, Jens Kehlet
2005-01-01
We present a summary of our theoretical results regarding CO oxidation on both oxide-supported and isolated gold nanoparticles. Using Density Functional Theory we have studied the adsorption of molecules and the oxidation reaction of CO on gold clusters. Low-coordinated sites on the gold...
Introduction: theoretical framework and research agenda
Zeitlin, J.; Zeitlin, J.
2015-01-01
This chapter introduces the theoretical framework and research agenda of the book. It provides an overview of the three contemporaneous trends from which the book departs: the development of experimentalist governance within the EU; the EU’s efforts to extend its rules, norms, standards, and governa
Theoretical Overview of Jet Photoproduction at HERA
Klasen, M.
1997-01-01
We review the theoretical framework of jet photoproduction at HERA discussing the conceptual ideas, phenomenological models, and higher order perturbative calculations. Numerically, we study the physically interesting distribution of transverse energy within the observed jet, the real and virtual photon structure, and the proton structure at large x.
Heavy Quarkonium Physics-Theoretical Status
Brambilla, N.; Vairo, A.
2007-01-01
Comment: To be published in Acta Physica Polonica, based on the invited talk given at 31st International Conference of Theoretical Physics: Matter to the Deepest: Recent Development in Physics of Fundamental Interactions, Ustron, Katowice, Poland, 5-11 Sep 2007. References added
Some Model Theoretic Remarks on Bass Modules
E. Momtahan
2011-09-01
Full Text Available We study Bass modules, Bass rings, and related concepts from a model theoretic point of view. We observe that the class of Bass modules (over a fixed ring is not stable under elementary equivalence. We observe that under which conditions the class of Bass rings are stable under elementary equivalence.
Theoretical Studies in Elementary Particle Physics
Collins, John C.; Roiban, Radu S
2013-04-01
This final report summarizes work at Penn State University from June 1, 1990 to April 30, 2012. The work was in theoretical elementary particle physics. Many new results in perturbative QCD, in string theory, and in related areas were obtained, with a substantial impact on the experimental program.
RELATIVISTIC HEAVY ION PHYSICS: A THEORETICAL OVERVIEW.
KHARZEEV,D.
2004-03-28
This is a mini-review of recent theoretical work in the field of relativistic heavy ion physics. The following topics are discussed initial conditions and the Color Glass Condensate; approach to thermalization and the hydrodynamic evolution; hard probes and the properties of the Quark-Gluon Plasma. Some of the unsolved problems and potentially promising directions for future research are listed as well.
THEORETICAL ASPECTS OF INTERNAL FINANCIAL CONTROL
Dzhamilya F. Ismailova
2013-01-01
Full Text Available The article considers the theoretical aspects of internal financial control, summarizes the definition formulated by scientists and experts, analyzed for differences between incompany and intrafarm control. The article discusses the collapse of Enron, notes the general provisions of various types of financial control.
Theoretical Perspectives of How Digital Natives Learn
Kivunja, Charles
2014-01-01
Marck Prensky, an authority on teaching and learning especially with the aid of Information and Communication Technologies, has referred to 21st century children born after 1980 as "Digital Natives". This paper reviews literature of leaders in the field to shed some light on theoretical perspectives of how Digital Natives learn and how…
Interview with John Ellis - Theoretical Physicist
CERN Audiovisual Service
2008-01-01
Q. 1. What is the importance or relationship between theoretical physics and the LHC project? Q. 2. What can be expected to happen on First Beam Day? Q. 3. What happens next in the story? Q. 4. What does this mean to you personally?
On Sociolinguistic Theoretical Basis of Brand Name
曹海洋; 司宇婷
2015-01-01
Brand names are the offspring of highly development of market economics, and play a crucial role in modern society. This paper discusses the soci-olinguistic theoretical basis of brand name. Attention should be paid to the cultural factors of brand naming, including customs and manners, religious beliefs, ethics, regional culture and so on.
Child Language Acquisition: Contrasting Theoretical Approaches
Ambridge, Ben; Lieven, Elena V. M.
2011-01-01
Is children's language acquisition based on innate linguistic structures or built from cognitive and communicative skills? This book summarises the major theoretical debates in all of the core domains of child language acquisition research (phonology, word-learning, inflectional morphology, syntax and binding) and includes a complete introduction…
Voltammetry at porous electrodes: A theoretical study
Barnes, Edward O; Li, Peilin; Compton, Richard G
2014-01-01
Theory is presented to simulate both chronoamperometry and cyclic voltammetry at porous electrodes fabricated by means of electro-deposition around spherical templates. A theoretical method to extract heterogeneous rate constants for quasireversible and irreversible systems is proposed by the approximation of decoupling of the diffusion within the porous electrode and of bulk diffusion to the electrode surface.
Theoretical Foundations of Learning Environments. Second Edition
Jonassen, David, Ed.; Land, Susan, Ed.
2012-01-01
"Theoretical Foundations of Learning Environments" provides students, faculty, and instructional designers with a clear, concise introduction to the major pedagogical and psychological theories and their implications for the design of new learning environments for schools, universities, or corporations. Leading experts describe the most…
Marketing services of higher education: theoretical aspect
Evgenyi Polonskyi
2014-05-01
Full Text Available The article is devoted to theoretical aspects of the use of marketing activities in institutions of higher education. The author analyzes of education from the standpoint of the marketing mix. The main factors of the external and internal environments affecting the educational institution.
An e-Learning Theoretical Framework
Aparicio, Manuela; Bacao, Fernando; Oliveira, Tiago
2016-01-01
E-learning systems have witnessed a usage and research increase in the past decade. This article presents the e-learning concepts ecosystem. It summarizes the various scopes on e-learning studies. Here we propose an e-learning theoretical framework. This theory framework is based upon three principal dimensions: users, technology, and services…
Measuring Poverty: Theoretical and Empirical Considerations
Iceland, John
2005-01-01
This article discusses the theoretical underpinnings of different types of income poverty measures--absolute, relative, and a National Academy of Sciences (NAS) "quasi-relative" one--and empirically assesses them by tracking their performance over time and across demographic groups. Part of the assessment involves comparing these measures to…
Theoretic Study of CⅡ Recombination Line
彭永伦; 王民盛; 韩小英; 李家明
2004-01-01
Using the R-matrix method, we carry out theoretical calculations for recombination line λ 8794 A(3d'-3p') of CⅡ, which is important to estimate the abundances of carbon in planetary nebulae. Our calculations are based on three sets of target orbital basis, through which we elucidate the electron correlation and static polarization effects in the dielectronic recombination processes.
New Theoretical Approach Integrated Education and Technology
Ding, Gang
2010-01-01
The paper focuses on exploring new theoretical approach in education with development of online learning technology, from e-learning to u-learning and virtual reality technology, and points out possibilities such as constructing a new teaching ecological system, ubiquitous educational awareness with ubiquitous technology, and changing the…
Theoretical Issues in the Tevatron Era
Rosner, Jonathan L
2000-01-01
The Fermilab Tevatron's operation for fixed-target physics from its start in 1983 until the end of fixed-target running in 2000 was marked by extraordinary peoductivity and variety. Some of the changing theoretal issues associated with this program are reviewed.
Formation of Massive Stars: Theoretical Considerations
Yorke, Harold W.
2008-01-01
This slide presentation reviews theoretical considerations of the formation of massive stars. It addresses the questions that assuming a gravitationally unstable massive clump, how does enough material become concentrated into a sufficiently small volume within a sufficiently short time? and how does the forming massive star influence its immediate surroundings to limit its mass?
Hybrid quantum teleportation: A theoretical model
Takeda, Shuntaro; Mizuta, Takahiro; Fuwa, Maria; Yoshikawa, Jun-ichi; Yonezawa, Hidehiro; Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)
2014-12-04
Hybrid quantum teleportation – continuous-variable teleportation of qubits – is a promising approach for deterministically teleporting photonic qubits. We propose how to implement it with current technology. Our theoretical model shows that faithful qubit transfer can be achieved for this teleportation by choosing an optimal gain for the teleporter’s classical channel.
Artificial neural networks: theoretical background and pharmaceutical applications: a review.
Wesolowski, Marek; Suchacz, Bogdan
2012-01-01
In recent times, there has been a growing interest in artificial neural networks, which are a rough simulation of the information processing ability of the human brain, as modern and vastly sophisticated computational techniques. This interest has also been reflected in the pharmaceutical sciences. This paper presents a review of articles on the subject of the application of neural networks as effective tools assisting the solution of various problems in science and the pharmaceutical industry, especially those characterized by multivariate and nonlinear dependencies. After a short description of theoretical background and practical basics concerning the computations performed by means of neural networks, the most important pharmaceutical applications of neural networks, with suitable references, are demonstrated. The huge role played by neural networks in pharmaceutical analysis, pharmaceutical technology, and searching for the relationships between the chemical structure and the properties of newly synthesized compounds as candidates for drugs is discussed.
Examining Asymmetrical Relationships of Organizational Learning Antecedents: A Theoretical Model
Ery Tri Djatmika
2016-02-01
Full Text Available Global era is characterized by highly competitive advantage market demand. Responding to the challenge of rapid environmental changes, organizational learning is becoming a strategic way and solution to empower people themselves within the organization in order to create a novelty as valuable positioning source. For research purposes, determining the influential antecedents that affect organizational learning is vital to understand research-based solutions given for practical implications. Accordingly, identification of variables examined by asymmetrical relationships is critical to establish. Possible antecedent variables come from organizational and personal point of views. It is also possible to include a moderating one. A proposed theoretical model of asymmetrical effects of organizational learning and its antecedents is discussed in this article.
Theoretical models for Type I and Type II supernova
Woosley, S.E.; Weaver, T.A.
1985-01-01
Recent theoretical progress in understanding the origin and nature of Type I and Type II supernovae is discussed. New Type II presupernova models characterized by a variety of iron core masses at the time of collapse are presented and the sensitivity to the reaction rate /sup 12/C(..cap alpha..,..gamma..)/sup 16/O explained. Stars heavier than about 20 M/sub solar/ must explode by a ''delayed'' mechanism not directly related to the hydrodynamical core bounce and a subset is likely to leave black hole remnants. The isotopic nucleosynthesis expected from these massive stellar explosions is in striking agreement with the sun. Type I supernovae result when an accreting white dwarf undergoes a thermonuclear explosion. The critical role of the velocity of the deflagration front in determining the light curve, spectrum, and, especially, isotopic nucleosynthesis in these models is explored. 76 refs., 8 figs.
A theoretical equation of state for detonation products
Shaw, M.S.
1998-12-31
A theoretical equation of state for detonation products is described that places particular emphasis on the characterization of small carbon clusters (20{angstrom}--50{angstrom} in diameter) in the products. Diamond clusters are modeled with the dangling bonds on the surface atoms (up to 30% of the cluster) capped by various radicals composed of C, H, N, and O from the background molecular fluid mixture. Free energy methods for the surface groups are used to determine the chemical equilibrium composition of the cluster surface as well as the surrounding molecular fluid mixture. The surface composition shows dramatic changes in composition over some regions and varies slowly in others. A perturbation theory approach is used for the mixture of molecular fluids that also includes features based on Monte Carlo simulations.
Experimental and theoretical study of metal combustion in oxygen flows
El-Rabii, Hazem; Muller, Maryse
2016-01-01
The effects of oxygen flow speed and pressure on the iron and mild steel combustion are investigated experimentally and theoretically. The studied specimens are vertical cylindrical rods subjected to an axial oxygen flow and ignited at the upper end by laser irradiation. Three main stages of the combustion process have been identified experimentally: (1) Induction period, during which the rod is heated until an intensive metal oxidation begins at its upper end; (2) Static combustion, during which a laminar liquid "cap" slowly grows on the upper rod end; and, after the liquid cap detachment from the sample, (3) Dynamic combustion, which is characterized by a rapid metal consumption and turbulent liquid motions. An analytical description of these stages is given. In particular, a model of the dynamic combustion is constructed based on the turbulent oxygen transport through the liquid metal-oxide flow. This model yields a simple expression for the fraction of metal burned in the process, and allows one to calcul...
Theoretical and numerical studies on morphological transitions in crack growth
Mühle, V
1999-01-01
This paper investigates the formation of crack patterns in stationary and transient temperature fields analytically with linear elastic fracture mechanics and numerically with the finite elements method (FEM). In particular, we consider the experimental situation of a narrow thin strip of hot glass slowly lowered into cold water, with temperature difference and velocity as variable parameters. The parameter regions of no crack, one straight crack and one oscillating crack are determined. The type of phase transition related to the borderline between straight and oscillating crack is characterized. The theoretical results are compared with those of other Similar investigations and comparisons are done for the propagation of multiple cracks. Quenching of a wide thin strip leads to a hierarchy of cracks whose scaling properties are analyzed. Without any fitting, theory and experiment agree surprisingly well.
Soft solids a primer to the theoretical mechanics of materials
Freed, Alan D
2014-01-01
This textbook presents the physical principles pertinent to the mathematical modeling of soft materials used in engineering practice, including both man-made materials and biological tissues. It is intended for seniors and masters-level graduate students in engineering, physics, or applied mathematics. It will also be a valuable resource for researchers working in mechanics, biomechanics, and other fields where the mechanical response of soft solids is relevant. Soft Solids: A Primer to the Theoretical Mechanics of Materials is divided into two parts. Part I introduces the basic concepts needed to give both Eulerian and Lagrangian descriptions of the mechanical response of soft solids. Part II presents two distinct theories of elasticity and their associated theories of viscoelasticity. Seven boundary-value problems are studied over the course of the book, each pertaining to an experiment used to characterize materials. These problems are discussed at the end of each chapter, giving students the opportunit...
[Methodological deficits in neuroethics: do we need theoretical neuroethics?].
Northoff, G
2013-10-01
Current neuroethics can be characterized best as empirical neuroethics: it is strongly empirically oriented in that it not only includes empirical findings from neuroscience but also searches for applications within neuroscience. This, however, neglects the social and political contexts which could be subject to a future social neuroethics. In addition, methodological issues need to be considered as in theoretical neuroethics. The focus in this article is on two such methodological issues: (1) the analysis of the different levels and their inferences among each other which is exemplified by the inference of consciousness from the otherwise purely neuronal data in patients with vegetative state and (2) the problem of linking descriptive and normative concepts in a non-reductive and non-inferential way for which I suggest the mutual contextualization between both concepts. This results in a methodological strategy that can be described as contextual fact-norm iterativity.
Boundary-induced nucleation control: a theoretical perspective
Buller, Oleg; Wang, Wenchong; Chi, Lifeng; Heuer, Andreas
2015-01-01
The prepatterning of a substrate with gold allows one to generate a variety of structures in vapor deposition experiments of organic semiconducting molecules. A particular interesting structure is generated if the gold is forming a rectangular grid. For specific combinations of the molecule flux, the substrate temperature and the lattice size it is possible to generate exactly one cluster per cell, denoted nucleation control. Here we show that the experimental observations of nucleation control can be very well understood from a theoretical perspective. For this purpose we perform, on the one hand, kinetic Monte Carlo simulations and, on the other hand, use scaling arguments to rationalize the observed behavior. For several observables, characterizing nucleation control, we find a very good agreement between experiment and theory.
A Game-Theoretic Model for Distributed Programming by Contract
Henriksen, Anders Starcke; Hvitved, Tom; Filinski, Andrzej
2009-01-01
We present an extension of the programming-by-contract (PBC) paradigm to a concurrent and distributed environment. Classical PBC is characterized by absolute conformance of code to its specification, assigning blame in case of failures, and a hierarchical, cooperative decomposition model – none...... of which extend naturally to a distributed environment with multiple administrative peers. We therefore propose a more nuanced contract model based on quantifiable performance of implementations; assuming responsibility for success; and a fundamentally adversarial model of system integration, where each...... component provider is optimizing its behavior locally, with respect to potentially conflicting demands. This model gives rise to a game-theoretic formulation of contract-governed process interactions that supports compositional reasoning about contract conformance....
Network Complexity Measures. An Information-Theoretic Approach.
Matthias Dehmer
2015-04-01
Full Text Available Quantitative graph analysis by using structural indices has been intricate in a sense that it often remains unclear which structural graph measures is the most suitable one, see [1, 12, 13]. In general, quantitative graph analysis deals with quantifying structural information of networks by using a measurement approach [5]. As special problem thereof is to characterize a graph quantitatively, that means to determine a measure that captures structural features of a network meaningfully. Various classical structural graph measures have been used to tackle this problem [13]. A fruitful approach by using information-theoretic [21] and statistical methods is to quantify the structural information content of a graph [1, 8, 18]. In this note, we sketch some classical information measures. Also, we briefly address the problem what kind of measures capture structural information uniquely. This relates to determine the discrimination power (or also called uniqueness of a graph measure, that is, how is the ability of the measures to discriminate non-isomorphic graphs structurally. [1] D. Bonchev. Information Theoretic Indices for Characterization of Chemical Structures. Research Studies Press, Chichester, 1983. [5] M. Dehmer and F. Emmert-Streib. Quantitative Graph Theory. Theory and Applications. CRC Press, 2014. [8] M. Dehmer, M. Grabner, and K. Varmuza. Information indices with high discriminative power for graphs. PLoS ONE, 7:e31214, 2012. [12] F. Emmert-Streib and M. Dehmer. Exploring statistical and population aspects of network complexity. PLoS ONE, 7:e34523, 2012. [13] F. Harary. Graph Theory. Addison Wesley Publishing Company, 1969. Reading, MA, USA. [18] A. Mowshowitz. Entropy and the complexity of the graphs I: An index of the relative complexity of a graph. Bull. Math. Biophys., 30:175–204, 1968. [21] C. E. Shannon and W. Weaver. The Mathematical Theory of Communication. University of Illinois Press, 1949.
A Graph Theoretic Perspective on CPM(Rel
Daniel Marsden
2015-11-01
Full Text Available Mixed states are of interest in quantum mechanics for modelling partial information. More recently categorical approaches to linguistics have also exploited the idea of mixed states to describe ambiguity and hyponym / hypernym relationships. In both these application areas the category Rel of sets and binary relations is often used as an alternative model. Selinger's CPM construction provides the setting for mixed states in Hilbert space based categorical quantum mechanics. By analogy, applying the CPM construction to Rel is seen as introducing mixing into a relational setting. We investigate the category CPM(Rel of completely positive maps in Rel. We show that the states of an object in CPM(Rel are in bijective correspondence with certain families of graphs. Via map-state duality this then allows us provide a graph theoretic characterization of the morphisms in CPM(Rel. By identifying an appropriate composition operation on graphs, we then show that CPM(Rel is isomorphic to a category of sets and graphs between them. This isomorphism then leads to a graph based description of the complete join semilattice enriched dagger compact structure of CPM(Rel. These results allow us to reason about CPM(Rel entirely in terms of graphs. We exploit these techniques in several examples. We give a closed form expression for the number of states of a finite set in CPM(Rel. The pure states are characterized in graph theoretic terms. We also demonstrate the possibly surprising phenomenon of a pure state that can be given as a mixture of two mixed states.
Theoretical chemistry in Belgium a topical collection from theoretical chemistry accounts
Champagne, Benoît; De Proft, Frank; Leyssens, Tom
2014-01-01
Readers of this volume can take a tour around the research locations in Belgium which are active in theoretical and computational chemistry. Selected researchers from Belgium present research highlights of their work. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format. This volume will be of benefit in particular to those research groups and libraries that have chosen to have only electronic access to the journal. It also provides valuable content for all researchers in theoretical chemistry.
Modelling in Accounting. Theoretical and Practical Dimensions
Teresa Szot-Gabryś
2010-10-01
Full Text Available Accounting in the theoretical approach is a scientific discipline based on specific paradigms. In the practical aspect, accounting manifests itself through the introduction of a system for measurement of economic quantities which operates in a particular business entity. A characteristic of accounting is its flexibility and ability of adaptation to information needs of information recipients. One of the main currents in the development of accounting theory and practice is to cover by economic measurements areas which have not been hitherto covered by any accounting system (it applies, for example, to small businesses, agricultural farms, human capital, which requires the development of an appropriate theoretical and practical model. The article illustrates the issue of modelling in accounting based on the example of an accounting model developed for small businesses, i.e. economic entities which are not obliged by law to keep accounting records.
Modeling business processes: theoretical and practical aspects
V.V. Dubininа
2015-06-01
Full Text Available The essence of process-oriented enterprise management has been examined in the article. The content and types of information technology have been analyzed in the article, due to the complexity and differentiation of existing methods, as well as the specificity of language, terminology of the enterprise business processes modeling. The theoretical aspects of business processes modeling have been reviewed and the modern traditional modeling techniques received practical application in the visualization model of retailers activity have been studied in the article. In the process of theoretical analysis of the modeling methods found that UFO-toolkit method that has been developed by Ukrainian scientists due to it systemology integrated opportunities, is the most suitable for structural and object analysis of retailers business processes. It was designed visualized simulation model of the business process "sales" as is" of retailers using a combination UFO-elements with the aim of the further practical formalization and optimization of a given business process.
Theoretical framework of community education improvement
Zaúl Brizuela Castillo
2015-05-01
Full Text Available The paper explains the connection between the approach selected for the analysis and development of community education and the contradictions manifested in its theoretical and practical comprehension. As a result, a comprehensive model for community education, describing the theoretical and methodological framework to improve community education, is devised. This framework is based on a conscious organizing of educative influences applied to the regular task of the community under the coordinate action of social institutions and organization that promote the transformational action of the neighborhood assuming a protagonist role in the improvement of the quality of live and morals related to the socialism updating process. The comprehensive model was proved experimentally at District 59 of San Miguel town; the transformation of the community was scientifically registered together with the information gather by means of observation and interviewing. The findings proved the pertinence and feasibility of the proposed model.
A Theoretical Analysis of Ball Spinning
无
2002-01-01
As a special method of manufacturing thin wall tubes, the ball spinning process has been used for nearly 30 years because of its less investment of equipment, higher precision, and more perfect properties of products. However, the application is limited since the process parameters are determined based on empirical data and laboratory experiments for lack of a whole theoretical analysis. In this paper, some basic parameters such as the force and power parameters have been studied based on an analysis of geometry and mechanics of the process. The calculation of forming forces and the selection of the working angle are carried out. At the end, a perfect comparison between the results of the experiments and the theoretical analysis is made.
Masochism: a clinical and theoretical overview.
Sack, R L; Miller, W
1975-08-01
This paper will review some of the theoretical and clinical features of masochism from an eclectic point of view. The topic of masochism has been taken up by authors of many perspectives because it addresses one of the anomalous, absurd, difficult-to-explain aspects of behavior for which no psychological system has an easy answer. Therefore, a wide-ranging literature on the topic of masochism is available. However, few previous reviewers have attempted to draw from a variety of disciplines and theoretical frameworks. In this review the historical development of the term and some of the psychoanalytic conceptualizations will be presented first. Since previous reviews of masochism from a strictly psychoanalytic perspective are adequate (Brenner, 1959; Eisenbud, 1967; Fenichel, 1945; Loewenstein, 1957; Panken, 1967), our discussions of masochism will be developed employing more extensively the interpersonal, social, learning theory, and biological perspectives.
Quantum probabilities: an information-theoretic interpretation
Bub, Jeffrey
2010-01-01
This Chapter develops a realist information-theoretic interpretation of the nonclassical features of quantum probabilities. On this view, what is fundamental in the transition from classical to quantum physics is the recognition that \\emph{information in the physical sense has new structural features}, just as the transition from classical to relativistic physics rests on the recognition that space-time is structurally different than we thought. Hilbert space, the event space of quantum systems, is interpreted as a kinematic (i.e., pre-dynamic) framework for an indeterministic physics, in the sense that the geometric structure of Hilbert space imposes objective probabilistic or information-theoretic constraints on correlations between events, just as the geometric structure of Minkowski space in special relativity imposes spatio-temporal kinematic constraints on events. The interpretation of quantum probabilities is more subjectivist in spirit than other discussions in this book (e.g., the chapter by Timpson)...
Theoretical aspects of spatial-temporal modeling
Matsui, Tomoko
2015-01-01
This book provides a modern introductory tutorial on specialized theoretical aspects of spatial and temporal modeling. The areas covered involve a range of topics which reflect the diversity of this domain of research across a number of quantitative disciplines. For instance, the first chapter provides up-to-date coverage of particle association measures that underpin the theoretical properties of recently developed random set methods in space and time otherwise known as the class of probability hypothesis density framework (PHD filters). The second chapter gives an overview of recent advances in Monte Carlo methods for Bayesian filtering in high-dimensional spaces. In particular, the chapter explains how one may extend classical sequential Monte Carlo methods for filtering and static inference problems to high dimensions and big-data applications. The third chapter presents an overview of generalized families of processes that extend the class of Gaussian process models to heavy-tailed families known as alph...
Evolution of Theoretical Perspectives in My Research
Otero, Valerie K.
2009-11-01
Over the past 10 years I have been using socio-cultural theoretical perspectives to understand how people learn physics in a highly interactive, inquiry-based physics course such as Physics and Everyday Thinking [1]. As a result of using various perspectives (e.g. Distributed Cognition and Vygotsky's Theory of Concept Formation), my understanding of how these perspectives can be useful for investigating students' learning processes has changed. In this paper, I illustrate changes in my thinking about the role of socio-cultural perspectives in understanding physics learning and describe elements of my thinking that have remained fairly stable. Finally, I will discuss pitfalls in the use of certain perspectives and discuss areas that need attention in theoretical development for PER.
Topics in modern physics theoretical foundations
Walecka, John Dirk
2013-01-01
While the two previous books entitled Introduction to Modern Physics: Theoretical Foundations and Advanced Modern Physics: Theoretical Foundations exposed the reader to the foundations and frontiers of today's physics, the goal of this third volume is to cover in some detail several topics omitted in the essentially linear progression of the first two. This book is divided into three parts. Part 1 is on quantum mechanics. Analytic solutions to the Schrödinger equation are developed for some basic systems. The analysis is then formalized, concluding with a set of postulates for the theory. Part 2 is on applications of quantum mechanics: approximation methods for bound states, scattering theory, time-dependent perturbation theory, and electromagnetic radiation and quantum electrodynamics. Part 3 covers some selected topics in relativistic quantum field theory: discrete symmetries, the Heisenberg picture, and the Feynman rules for quantum chromodynamics. The three volumes in this series taken together provide ...
Theoretical description of metabolism using queueing theory.
Evstigneev, Vladyslav P; Holyavka, Marina G; Khrapatiy, Sergii V; Evstigneev, Maxim P
2014-09-01
A theoretical description of the process of metabolism has been developed on the basis of the Pachinko model (see Nicholson and Wilson in Nat Rev Drug Discov 2:668-676, 2003) and the queueing theory. The suggested approach relies on the probabilistic nature of the metabolic events and the Poisson distribution of the incoming flow of substrate molecules. The main focus of the work is an output flow of metabolites or the effectiveness of metabolism process. Two simplest models have been analyzed: short- and long-living complexes of the source molecules with a metabolizing point (Hole) without queuing. It has been concluded that the approach based on queueing theory enables a very broad range of metabolic events to be described theoretically from a single probabilistic point of view.
Theoretical study on single-molecule spectroscopy
SHAN Guang-cun; HUANG Wei
2006-01-01
The photon-by-photon approach for single molecule spectroscopy experiments utilizes the information carried by each detected photon and allows the measurements of conformational fluctuation with time resolution on a vast range of time scales,where each photon represents a data point.Here,we theoretically simulate the photon emission dynamics of a single molecule spectroscopy using the kinetic Monte Carlo algorithm to understand the underlying complex photon dynamic process of a single molecule.In addition,by following the molecular process in real time,the mechanism of complex biochemical reactions can be revealed.We hope that this theoretical study will serve as an introduction and a guideline into this exciting new field.
A unified grand tour of theoretical physics
Lawrie, Ian D
2013-01-01
A Unified Grand Tour of Theoretical Physics invites its readers to a guided exploration of the theoretical ideas that shape our contemporary understanding of the physical world at the fundamental level. Its central themes, comprising space-time geometry and the general relativistic account of gravity, quantum field theory and the gauge theories of fundamental forces, and statistical mechanics and the theory of phase transitions, are developed in explicit mathematical detail, with an emphasis on conceptual understanding. Straightforward treatments of the standard models of particle physics and cosmology are supplemented with introductory accounts of more speculative theories, including supersymmetry and string theory. This third edition of the Tour includes a new chapter on quantum gravity, focusing on the approach known as Loop Quantum Gravity, while new sections provide extended discussions of topics that have become prominent in recent years, such as the Higgs boson, massive neutrinos, cosmological perturba...
Theoretical highlights of neutrino-nucleus interactions
Alvarez-Ruso, Luis
2009-01-01
The recent theoretical developments in the field of neutrino-nucleus interactions in the few-GeV region are reviewed based on the presentations made at the NuInt09 Workshop. The topics of electron scattering and its connections with neutrino interactions, neutrino induced quasielastic scattering and pion production (coherent and incoherent) are covered, with special emphasis on the challenges that arise in the comparison with new experimental data.
THEORETICAL FOUNDATIONS OF HOSPITAL PHARMACY MANAGEMENT
Paradis, Johanne; Gauthier, Jacques-Bernard
2016-01-01
The lack of interest of researchers in relation to question of hospital pharmacy management, and the status quo of existing managerial practices serving the reforms, justifies analysis of theoretical foundations of hospital pharmacy management. The objective is twofold. First, provide an overview of the socio-historical eras of the organizational theories in order to position the hospital pharmacy management on the axis of the changing ways of thinking about the organization and management. S...
THEORETICAL BASES OF DANCE/MOVEMENT THERAPY
Садыкова, Д. А.
2015-01-01
The article is devoted to dance/movement therapy — a special kind of psychotherapy that uses a dance movement for the development of social, emotional and physical life of the individual. This is a form of psychosomatic treatment aimed at identifying links between mental conflicts and somatic symptoms, on exemption from physical and mental stress. The article examines the theoretical foundations of dance therapy, his¬tory of its formation, basic directions and forms of work.
Theoretical aspects of studying the migration processes
Dilfuza Rasulova
2010-02-01
Full Text Available In conditions of continuous growth of population in Uzbekistan the issue of managing the labor migration processes is becoming more important. Effective coordination of migration processes requires comprehensive study of theory and methodology of labour migration, particularly considering cases of transition countries. The paper considers some theoretic concepts that seem important for understanding the mechanism of migration princesses, suggests practical recommendations for the associated decision-making.
Theoretical nuclear structure. Progress report for 1997
Nazarewicz, W.; Strayer, M.R.
1997-12-31
This research effort is directed toward theoretical support and guidance for the fields of radioactive ion beam physics, gamma-ray spectroscopy, and the interface between nuclear structure and nuclear astrophysics. The authors report substantial progress in all these areas. One measure of progress is publications and invited material. The research described here has led to more than 25 papers that are published, accepted, or submitted to refereed journals, and to 25 invited presentations at conferences and workshops.
Theoretical Calculations of Atomic Data for Spectroscopy
Bautista, Manuel A.
2000-01-01
Several different approximations and techniques have been developed for the calculation of atomic structure, ionization, and excitation of atoms and ions. These techniques have been used to compute large amounts of spectroscopic data of various levels of accuracy. This paper presents a review of these theoretical methods to help non-experts in atomic physics to better understand the qualities and limitations of various data sources and assess how reliable are spectral models based on those data.
Error Estimates of Theoretical Models: a Guide
Dobaczewski, J; Reinhard, P -G
2014-01-01
This guide offers suggestions/insights on uncertainty quantification of nuclear structure models. We discuss a simple approach to statistical error estimates, strategies to assess systematic errors, and show how to uncover inter-dependencies by correlation analysis. The basic concepts are illustrated through simple examples. By providing theoretical error bars on predicted quantities and using statistical methods to study correlations between observables, theory can significantly enhance the feedback between experiment and nuclear modeling.
Theoretical Foundations of Buffer Stock Saving
Christopher D Carroll
2009-01-01
"Buffer-stock" versions of the dynamic stochastic optimizing model of saving are now standard in the consumption literature. This paper builds theoretical foundations for rigorous understanding of the main characteristics of buffer stock models, including the existence of a target level of wealth and the proposition that aggregate consumption growth equals aggregate income growth in a small open economy populated by buffer stock consumers.
A theoretical model of atmospheric ozone depletion
Midya, S. K.; Jana, P. K.; Lahiri, T.
1994-01-01
A critical study on different ozone depletion and formation processes has been made and following important results are obtained: (i) From analysis it is shown that O3 concentration will decrease very minutely with time for normal atmosphere when [O], [O2] and UV-radiation remain constant. (ii) An empirical equation is established theoretically between the variation of ozone concentration and time. (iii) Special ozone depletion processes are responsible for the dramatic decrease of O3-concentration at Antarctica.
Theoretical developments in psychosocial work environment research.
Johnson, J V
1989-01-01
This article introduces the fourth series of articles in the Special Section on work organization and health. The authors identify the theory of scientific management as one of the major obstacles to workplace democratization efforts. The application of this theory has led to the centralization of workplace knowledge and skill under managerial control. The articles in this issue criticize this conventional theory of job design and suggest new theoretical directions from psychological, sociological, and political-economic perspectives.
Theoretical model of smooth disk operation
Krauze, K.
1985-02-01
Aes a theoretical model is analyzed for coal cutting by disk cutters mounted on a helical cutting drum of a shearer loader. The model is based on the assumption that failure of coal cohesion is caused by crushing and separation of coal grains from a coal face and that coal cutting resistance depends on its contact strength as well as cutting depth and cutting angle. 1 reference.
Theoretical approaches to social innovation – A critical literature review
Butzin, A.; Davis, A.; Domanski, D.; Dhondt, S.; Howaldt, J.; Kaletka, C.; Kesselring, A.; Kopp, R.; Millard, J.; Oeij, P.; Rehfeld, D.; Schaper-Rinkel, P.; Schwartz, M.; Scoppetta, A.; Wagner-Luptacik, P.; Weber, M.
2014-01-01
The SI-DRIVE report “Theoretical approaches to Social Innovation – A Critical Literature Review” delivers a comprehensive overview on the state of the art of theoretically relevant building blocks for advancing a theoretical understanding of social innovation. It collects different theoretical
Theoretical resources for a globalised bioethics.
Verkerk, Marian A; Lindemann, Hilde
2011-02-01
In an age of global capitalism, pandemics, far-flung biobanks, multinational drug trials and telemedicine it is impossible for bioethicists to ignore the global dimensions of their field. However, if they are to do good work on the issues that globalisation requires of them, they need theoretical resources that are up to the task. This paper identifies four distinct understandings of 'globalised' in the bioethics literature: (1) a focus on global issues; (2) an attempt to develop a universal ethical theory that can transcend cultural differences; (3) an awareness of how bioethics itself has expanded, with new centres and journals emerging in nearly every corner of the globe; (4) a concern to avoid cultural imperialism in encounters with other societies. Each of these approaches to globalisation has some merit, as will be shown. The difficulty with them is that the standard theoretical tools on which they rely are not designed for cross-cultural ethical reflection. As a result, they leave important considerations hidden. A set of theoretical resources is proposed to deal with the moral puzzles of globalisation. Abandoning idealised moral theory, a normative framework is developed that is sensitive enough to account for differences without losing the broader context in which ethical issues arise. An empirically nourished, self-reflexive, socially inquisitive, politically critical and inclusive ethics allows bioethicists the flexibility they need to pick up on the morally relevant particulars of this situation here without losing sight of the broader cultural contexts in which it all takes place.
Managing Logistics Information System: Theoretical Underpinning
Adebambo Somuyiwa
2010-05-01
Full Text Available The research sought to explain the theoretical background of articulating effective logistics information system in any industrial outfit. This is predicated on the fact that logistics is “the process of strategically managing the acquisition, movement and storage of materials, parts and finished inventory (and the related information flow s through the organisation and its marketing channel in such a way that current and future profitability is maximized through the cost-effective fulfillment of orders. However, the theoretical basis of the information has not been fully understood within the context of logistics system , such that it will give a pointer to how those inherent costs could be managed or saved, as well as enhanced supplier-customer collaborative relationships. It is in the light of this that the paper attempt to give theoretical considerations, through descriptive methodology approach, on how those basic objectives of logistics can be achieved and its ultimate goal can be realized. The study concluded that emphasis should be placed on attributes of logistics information systems and particularly information cost in order to enhance logistics efficiency and effectiveness.
Heritage protection, technological culture and theoretical weakness
Lucina Napoleone
2015-12-01
Full Text Available In the last decades, the values that have guided traditionally the theoretical approach in the field of restoration (such as truth, beauty, authenticity, etc… were more and more weakened. At the same time, the technical knowledge, traditionally seen as means to reach some goals conceived in a theoretical context, has had an impressive increase. In the recent past, each one of the theoretical positions – such as conservation, restoration, re-use, renovation, etc – has bent technology to its ideas and has used the progress to reach its goals. However, now we have an inversion of trend: technology has corroded ideas and goals. As the philosopher Emanuele Severino has argued, the instruments which a man has, have the tendency to transform their nature: they turn from means into goals. Thanks to the capability to offer efficient and cost-effective solutions, technology has put theory into the background. Technology feeds on itself, generating needs that will be satisfied by further technological advances, while theory is suffering dramatically, as it is only able to rough out generic horizons. This paper proposes some reflections about the importance of integrating theory into the technological and scientific processes, in order to impose external restrictions related to ethics, authenticity and responsibility. Keywords: protection, heritage, theory, technique, restoration
The Teleological Resocialization: theoretical-praxeological basis
Sławomir Sobczak
2011-12-01
Full Text Available Resocialization and Social Prevention is a theoretical and a praxeological subject, thus teleology of resocialization as its building block should relate both to its theoretical and practical aspects, i.e. to goals and postulates formed on the basis of paradigms and diagnosis. In the article are pointed out the reasons for forming teleology of resocialization due to the foundation of fundamental thinking, i.e. monistic basis (idealism, materialism and pluralism (realism and also the outcomes of making presumptions in aspects of the process of planning deliberate actions. On one hand the modern praxeology points to forming the goals of the treatment in the phase of equifinality on the basis of the diagnosis as an information on the system, on the other hand the theoretical aspect of resocialization teleology is described imprecisely, from only one angle. In resocialization teleology there is a narrowing to idealistic or material thinking, which considers axiology as the foundation of forming goals, according to their way of thinking. Having a particular way of thinking is not a mistake. It is, however, a mistake to inform the reader in books that this way of thinking is the only way, though not too suitable, but having no alternative. In the available literature on the subject both the axiological and anthropological bases of teleology are formed. Therefore, neither the axiology nor anthropology should be mentioned as an equivalent to teleology, instead the teleology as a knowledge can only be based on either the axiology or anthropology.
Theoretical study on a water muffler
Du, T.; Chen, Y. W.; Miao, T. C.; Wu, D. Z.
2016-05-01
Theoretical computation on a previously studied water muffler is carried out in this article. Structure of the water muffler is composed of two main parts, namely, the Kevlar- reinforced rubber tube and the inner-noise-reduction structure. Rubber wall of the rubber tube is assumed to function as rigid wall lined with sound absorption material and is described by a complex radial wave number. Comparison among the results obtained from theoretical computation, FEM (finite element method) simulation and experiment of the rubber tube and that of the water muffler has been made. The theoretical results show a good accordance in general tendency with the FEM simulated and the measured results. After that, parametric study on the diameter of the inner structure and that of the rubber tube is conducted. Results show that the diameter of the left inner structure has the most significant effect on the SPL of the water muffler due to its location and its effect on the diameter ratio D2/D1.
Experimental and Theoretical Studies on Biologically Active Lanthanide (III) Complexes
Kostova, I.; Trendafilova, N.; Georgieva, I.; Rastogi, V. K.; Kiefer, W.
2008-11-01
The complexation ability and the binding mode of the ligand coumarin-3-carboxylic acid (HCCA) to La(III), Ce(III), Nd(III), Sm(III), Gd(III) and Dy(III) lanthanide ions (Ln(III)) are elucidated at experimental and theoretical level. The complexes were characterized using elemental analysis, DTA and TGA data as well as 1H NMR and 13C NMR spectra. FTIR and Raman spectroscopic techniques as well as DFT quantum chemical calculations were used for characterization of the binding mode and the structures of lanthanide(III) complexes of HCCA. The metal—ligand binding mode is predicted through molecular modeling and energy estimation of different Ln—CCA structures using B3LYP/6-31G(d) method combined with a large quasi-relativistic effective core potential for lanthanide ion. The energies obtained predict bidentate coordination of CCA- to Ln(III) ions through the carbonylic oxygen and the carboxylic oxygen. Detailed vibrational analysis of HCCA, CCA- and Ln(III) complexes based on both calculated and experimental frequencies confirms the suggested metal—ligand binding mode. The natural bonding analysis predicts strongly ionic character of the Ln(III)-CCA bonding in the- complexes studied. With the relatively resistant tumor cell line K-562 we obtained very interesting in-vitro results which are in accordance with our previously published data concerning the activity of lanthanide(III) complexes with other coumarin derivatives.
Theoretical accuracy in cosmological growth estimation
Bose, Benjamin; Koyama, Kazuya; Hellwing, Wojciech A.; Zhao, Gong-Bo; Winther, Hans A.
2017-07-01
We elucidate the importance of the consistent treatment of gravity-model specific nonlinearities when estimating the growth of cosmological structures from redshift space distortions (RSD). Within the context of standard perturbation theory (SPT), we compare the predictions of two theoretical templates with redshift space data from COLA (comoving Lagrangian acceleration) simulations in the normal branch of DGP gravity (nDGP) and general relativity (GR). Using COLA for these comparisons is validated using a suite of full N-body simulations for the same theories. The two theoretical templates correspond to the standard general relativistic perturbation equations and those same equations modeled within nDGP. Gravitational clustering nonlinear effects are accounted for by modeling the power spectrum up to one-loop order and redshift space clustering anisotropy is modeled using the Taruya, Nishimichi and Saito (TNS) RSD model. Using this approach, we attempt to recover the simulation's fiducial logarithmic growth parameter f . By assigning the simulation data with errors representing an idealized survey with a volume of 10 Gpc3/h3 , we find the GR template is unable to recover fiducial f to within 1 σ at z =1 when we match the data up to kmax=0.195 h /Mpc . On the other hand, the DGP template recovers the fiducial value within 1 σ . Further, we conduct the same analysis for sets of mock data generated for generalized models of modified gravity using SPT, where again we analyze the GR template's ability to recover the fiducial value. We find that for models with enhanced gravitational nonlinearity, the theoretical bias of the GR template becomes significant for stage IV surveys. Thus, we show that for the future large data volume galaxy surveys, the self-consistent modeling of non-GR gravity scenarios will be crucial in constraining theory parameters.
Quantum turbulence: Theoretical and numerical problems
Nemirovskii, Sergey K.
2013-03-01
The term “quantum turbulence” (QT) unifies the wide class of phenomena where the chaotic set of one dimensional quantized vortex filaments (vortex tangles) appear in quantum fluids and greatly influence various physical features. Quantum turbulence displays itself differently depending on the physical situation, and ranges from quasi-classical turbulence in flowing fluids to a near equilibrium set of loops in phase transition. The statistical configurations of the vortex tangles are certainly different in, say, the cases of counterflowing helium and a rotating bulk, but in all the physical situations very similar theoretical and numerical problems arise. Furthermore, quite similar situations appear in other fields of physics, where a chaotic set of one dimensional topological defects, such as cosmic strings, or linear defects in solids, or lines of darkness in nonlinear light fields, appear in the system. There is an interpenetration of ideas and methods between these scientific topics which are far apart in other respects. The main purpose of this review is to bring together some of the most commonly discussed results on quantum turbulence, focusing on analytic and numerical studies. We set out a series of results on the general theory of quantum turbulence which aim to describe the properties of the chaotic vortex configuration, starting from vortex dynamics. In addition we insert a series of particular questions which are important both for the whole theory and for the various applications. We complete the article with a discussion of the hot topic, which is undoubtedly mainstream in this field, and which deals with the quasi-classical properties of quantum turbulence. We discuss this problem from the point of view of the theoretical results stated in the previous sections. We also included section, which is devoted to the experimental and numerical suggestions based on the discussed theoretical models.
Theoretical and Experimental Beam Plasma Physics (TEBPP)
Roberts, B.
1986-01-01
The theoretical and experimental beam plasma physics (TEBPP) consists of a package of five instruments to measure electric and magnetic fields, plasma density and temperature, neutral density, photometric emissions, and energetic particle spectra during firings of the particle injector (SEPAC) electron beam. The package is developed on a maneuverable boom (or RMS) and is used to measure beam characteristics and induced perturbations field ( 10 m) and mid field ( 10 m to 100 m) along the electron beam. The TEBPP package will be designed to investigate induced oscillations and induced electromagnetic mode waves, neutral and ion density and temperature effects, and beam characteristics as a function of axial distance.
Measuring observability by generalized information theoretic quantities
Badong CHEN; Jinchun HU; Hongbo LI; Zengqi SUN
2008-01-01
A normalized measure is established to provide the quantitative information about the degree of observabilty for the discrete-time,stochastically autonomous system.This measure is based on the generalized information theoretic quanties(generalized entropy,mutual information) of the system state and the observations.where the system state can be a discrete or a continuous random vector.Some important properties are presented.For the linear case,the explicit formula for the degree of observability is derived,and the equivalence between the proposed measure and the traditional ranK condition is proved The curves for the degree of observability are depicted in a simple example.
Theoretical Aspects of the Heavy Quark Expansion
Uraltsev, N
1996-01-01
I give a brief outline of the theoretical framework for the modern treatment of the strong interaction effects in heavy quark decays, based on first principles of QCD. This model-independent approach is required to meet the precision of current and future experiments. Applications to a few problems of particular practical interest are reviewed, including the precise determination of V_{cb} and V_{ub}. I emphasize the peculiarities of simultaneously accounting for the perturbative and power-suppressed effects necessary for accurate predictions.
A signal theoretic introduction to random processes
Howard, Roy M
2015-01-01
A fresh introduction to random processes utilizing signal theory By incorporating a signal theory basis, A Signal Theoretic Introduction to Random Processes presents a unique introduction to random processes with an emphasis on the important random phenomena encountered in the electronic and communications engineering field. The strong mathematical and signal theory basis provides clarity and precision in the statement of results. The book also features: A coherent account of the mathematical fundamentals and signal theory that underpin the presented material Unique, in-depth coverage of
A theoretical framework for analysing preschool teaching
Chaiklin, Seth
2014-01-01
This article introduces a theoretical framework for analysing preschool teaching as a historically-grounded societal practice. The aim is to present a unified framework that can be used to analyse and compare both historical and contemporary examples of preschool teaching practice within and across...... national traditions. The framework has two main components, an analysis of preschool teaching as a practice, formed in relation to societal needs, and an analysis of the categorical relations which necessarily must be addressed in preschool teaching activity. The framework is introduced and illustrated...
Experimental and theoretical advances in fluid dynamics
Klapp, Jaime; Fuentes, Oscar Velasco
2011-01-01
The book is comprised of lectures and selected contributions presented at the Enzo Levi and XVI Annual Meeting of the Fluid Dynamic Division of the Mexican Physical Society in 2010. It is aimed at fourth year undergraduate and graduate students, as well as scientists in the fields of physics, engineering and chemistry with an interest in fluid dynamics from the experimental and theoretical point of view. The lectures are introductory and avoid the use of complicated mathematics. The other selected contributions are also geared to fourth year undergraduate and graduate students. The fluid dynam
Disability and Humans Rights: A Theoretical Analysis
PATRICIA CUENCA GÓMEZ
2015-06-01
Full Text Available Since Enlightenment, theories of justice and, in particular, theories of human rights have been based on principles which are excludable for people with disabilities. The exclusion has not been resolved by contemporary theories of justice. A profound review of some basic assumptions is required to get a full and sound theory of human rights including people with disabilities in equal terms. The inclusion of people with disabilities is an urgent theoretical challenge which must be face in order to perform a sound reform of rules in legal practice.
Theoretical Survey of Higgs Boson and Axions
Morales, Robert O.
2000-04-05
The success as well as the problems of the minimal Standard Model are recalled. The authors survey essentially this Model and the theory of the standard axion (Nambu-Goldstone boson). Possible invisible and visualized (theoretical) axions are discussed as are certain astrophysical aspects of the existence of an axion. They survey also axion cosmology in superstring models and its consequence, in the new anomaly cancellation mechanism to the sense of Green and Schwarz. Recent results for the search of the Higgs boson, and the axion are resumed. A great important is reserved for discussion of the Standard Model.
Field theoretic description of partially reflective surfaces
Barone, F E
2014-01-01
The issue of electric charges in interaction with partially reflective surfaces is addressed by means of field theoretic methods. It is proposed an enlarged Maxwell lagrangian, describing the electromagnetic field in the presence of a semitransparent surface, and its corresponding photon propagator is computed exactly. The amended Green function reduces to the one for a perfect conductor in the appropriate limit, and leads to the interaction between charges and surfaces with varying degrees of transparency, featured by a phenomenological parameter. The interaction found via image method is recovered, in the limiting case of perfect mirrors, as a testimony to the validity of the model.
[Experimental and theoretical high energy physics program
Finley, J.; Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.
1993-04-01
Experimental and theoretical high-energy physics research at Purdue is summarized in a number of reports. Subjects treated include the following: the CLEO experiment for the study of heavy flavor physics; gas microstrip detectors; particle astrophysics; affine Kac{endash}Moody algebra; nonperturbative mass bounds on scalar and fermion systems due to triviality and vacuum stability constraints; resonance neutrino oscillations; e{sup +}e{sup {minus}} collisions at CERN; {bar p}{endash}p collisions at FNAL; accelerator physics at Fermilab; development work for the SDC detector at SSC; TOPAZ; D-zero physics; physics beyond the standard model; and the Collider Detector at Fermilab. (RWR)
Advances in theoretical models of network science
FANG Jin-qing; BI Qiao; LI Yong
2007-01-01
In this review article, we will summarize the main advances in network science investigated by the CIAE Group of Complex Network in this field. Several theoretical models of network science were proposed and their topological and dynamical properties are reviewed and compared with the other models. Our models mainly include a harmonious unifying hybrid preferential model, a large unifying hybrid network model, a quantum interference network, a hexagonal nanowire network, and a small-world network with the same degree. The models above reveal some new phenomena and findings, which are useful for deeply understanding and investigating complex networks and their applications.
Modeling of alkynes: synthesis and theoretical properties
Renato Rosseto
2003-06-01
Full Text Available In this paper we present the synthesis and simulation of alkynes derivatives. Semiempirical calculations were carried out for the ground and first excited states, including the spectroscopic properties of the absorption and emission (fluorescence and phosphorescence spectra by INDO/S-CI and DNdM-INDO/S-CI methods with geometries fully optimized by PM3/CI. The fact that the theoretical spectra are in accord with the experimental absorption spectra gives us a new possible approach on how structure modifications could affect the non-linear optical properties of alkynes.
Theoretically palatable flavor combinations of astrophysical neutrinos
Bustamante, Mauricio; Winter, Walter
2015-01-01
The flavor composition of high-energy astrophysical neutrinos can reveal the particle physics governing their production, propagation, and interaction. The IceCube Collaboration has published the first experimental determination of the ratio of each flavor to the total flux. We present, as a theoretical counterpart, new results for the full range of received flavor ratios for arbitrary flavor ratios in the sources. With just standard neutrino mixing, this range is quite small. Even when a broad class of new-physics effects is included, it remains surprisingly small. Our results will allow IceCube to more quickly identify when their measurements imply standard, new, or truly exotic physics.
The Theoretical Practices of Physics Philosophical Essays
Hughes, R I G
2009-01-01
R.I.G Hughes presents a series of eight philosophical essays on the theoretical practices of physics. The first two essays examine these practices as they appear in physicists' treatises (e.g. Newton's Principia and Opticks) and journal articles (by Einstein, Bohm and Pines, Aharonov and Bohm). By treating these publications as texts, Hughes casts the philosopher of science in the role of critic. This premise guides the following 6 essays which deal with variousconcerns of philosophy and physics such as laws, disunities, models and representation, computer simulation, explanation, and the disc
Reasoning about Action: An Argumentation - Theoretic Approach
Foo, N Y; 10.1613/jair.1602
2011-01-01
We present a uniform non-monotonic solution to the problems of reasoning about action on the basis of an argumentation-theoretic approach. Our theory is provably correct relative to a sensible minimisation policy introduced on top of a temporal propositional logic. Sophisticated problem domains can be formalised in our framework. As much attention of researchers in the field has been paid to the traditional and basic problems in reasoning about actions such as the frame, the qualification and the ramification problems, approaches to these problems within our formalisation lie at heart of the expositions presented in this paper.
CO oxidation on gold nanoparticles: Theoretical studies
Remediakis, Ioannis; Lopez, Nuria; Nørskov, Jens Kehlet
2005-01-01
We present a summary of our theoretical results regarding CO oxidation on both oxide-supported and isolated gold nanoparticles. Using Density Functional Theory we have studied the adsorption of molecules and the oxidation reaction of CO on gold clusters. Low-coordinated sites on the gold...... nanoparticles can adsorb small inorganic molecules such as O2 and CO, and the presence of these sites is the key factor for the catalytic properties of supported gold nanoclusters. Other contributions, induced by the presence of the support, can provide parallel channels for the reaction and modulate the final...
Theoretical Model of Steel Continuous Casting Technology
C Gheorghies; I Crudu; C Teletin; C Spanu
2009-01-01
A theoretical model adapted for studying steel continuous casting technology was proposed.The model based on system theory contained input/output,command,and control parameters.The process was divided into five stages,i.e.,tundish,mold,guiding system,guiding-drawing system,and guiding-drawing-soft reduction system.The model can be used to describe the physicoehemical processes,thermal processes,chemical processes,and characteristics of the cast material according to the above-mentioned stages.It can also be applied to other metallurgical technologies and even to other industries (chemistry,food,etc.).
Almost Free Modules Set-Theoretic Methods
Eklof, PC
1990-01-01
This is an extended treatment of the set-theoretic techniques which have transformed the study of abelian group and module theory over the last 15 years. Part of the book is new work which does not appear elsewhere in any form. In addition, a large body of material which has appeared previously (in scattered and sometimes inaccessible journal articles) has been extensively reworked and in many cases given new and improved proofs. The set theory required is carefully developed with algebraists in mind, and the independence results are derived from explicitly stated axioms. The book contains exe
Theoretical determination of cesiated work functions
Szejn, R. M.
1972-01-01
A computer program based on the theoretical work of Gyftopoulos, Steiner, and Levine on bimetallic systems and using a modified version of Wilkins' SIMCON subroutine SURFAS was written for the Univac 1108. This program, WFGSL, accepts the operating conditions and the physical parameters pertinent to the substrate and adsorbate, and outputs the field-free work function, electron current (Richardson equation), ion current (Saha equation), and fractional substrate coverage by the adsorbate. A brief description of the theory is presented together with a program description and listing. An application of the program to a bimetallic system of cesium (adsorbate) and rhenium (substrate) is also described.
Numerical modelling of corrosion - Theoretical backgrounds -
Warkus, J.; Raupach, M. [ibac, RWTH Aachen (Germany); Gulikers, J. [Ministry of Transport, Rijkswaterstaat, Bouwdienst, Utrecht (Netherlands)
2006-08-15
During recent years research projects with different approaches have been carried out to develop models which are suitable to assess the metal removal rate in case of reinforcement corrosion. Some of them are based on empirical methods and correlate the corrosion rate to parameters like concrete resistivity, temperature and relative humidity. Another type of model is based on a quantification of the ongoing electrochemical processes. In this paper the theoretical backgrounds and mathematical descriptions of reinforcement corrosion with regard to a numerical modelling are presented and discussed. (Abstract Copyright [2006], Wiley Periodicals, Inc.)
Graph-theoretic strengths of contextuality
de Silva, Nadish
2017-03-01
Cabello-Severini-Winter and Abramsky-Hardy (building on the framework of Abramsky-Brandenburger) both provide classes of Bell and contextuality inequalities for very general experimental scenarios using vastly different mathematical techniques. We review both approaches, carefully detail the links between them, and give simple, graph-theoretic methods for finding inequality-free proofs of nonlocality and contextuality and for finding states exhibiting strong nonlocality and/or contextuality. Finally, we apply these methods to concrete examples in stabilizer quantum mechanics relevant to understanding contextuality as a resource in quantum computation.
Theoretical and Conceptual Issues in Political Marketing
Ormrod, Robert P.; Henneberg, Stephan C.; O'Shaughnessy, Nicholas J.
field of political science. However, it is our opinion that the theoretical and conceptual foundations of political marketing have yet to be explored and mapped in sufficient depth. Motivated by this deficiency and building on the work in Ormrod, Henneberg and O’Shaughnessy (2013), this paper aims...... in the rhetoric that characterised political discourse in ancient Greece and Rome; however, the modern use of political marketing began with the widespread adoption of the mass media as a vehicle for political communication to voters, first using election posters and radio, and then, in the 1950’s, television...
Han, Dahai; Liu, Yile; Zhang, Kai; Luo, Pengfei; Zhang, Min
2012-07-02
Diversity reception technology is introduced into ultraviolet communication area in this article with theory analysis and practical experiment. The idea of diversity reception was known as a critical effective method in wireless communication area that improves the Gain significantly especially for the multi-scattering channel. A theoretical modeling and simulation method are proposed to depict the principle and feasibility of diversity reception adopted in UV communication. Besides, an experimental test-bed using ultraviolet LED and dual receiver of photomultiplier tube is setup to characterize the effects of diversity receiving in non-line-of-sight (NLOS) ultraviolet communication system. The experiment results are compared with the theoretical ones to verify the accuracy of theoretical modeling and the effect of diversity reception. Equal gain combining (EGC) method was adopted as the diversity mechanism in this paper. The research results of theory and experiment provide insight into the channel characteristics and achievable capabilities of ultraviolet communication system with diversity receiving method.
Characterization of refractive index distribution of polymer optical fiber
无
2002-01-01
A focusing method is developed to characterize the refractive index profile of polymer optical fiber (POF). Based on the refractive index profile the theoretical bandwidth and the core index exponentα (α > 0) of POF are calculated. The results show that the value of theoretical bandwidth agrees well with the experimental data.
Organisational Learning: Theoretical Shortcomings and Practical Challenges
Jon Aarum Andersen
2014-05-01
Full Text Available This paper addresses two problems related to learning and the use of knowledge at work. The first problem is the theoretical shortcomings stemming from the controversy between three different concepts of ‘organisational learning.’ In order to enhance scholarship in this field the notion that organisations - as organisations - can learn need to be rejected for theoretical and empirical reasons. The metaphorical use of ‘organisational learning’ creates only confusion. Learning is a process and knowledge is the outcome of that process. It is argued that learning and knowledge is only related to individuals. Knowledge is thus the individual capability to draw distinctions, within a domain of action, based on an appreciation of context or theory. Consequently, knowledge becomes organisational when it is created, developed and transmitted to other individuals in the organisation. In a strict sense knowledge becomes organisational when employees use it and act based on generalisations due to the rules and procedures found in their organisation. The gravest problem is practical challenges due to the fact that the emphasis on learning, knowledge and competence of the working force do not materialize in the application of the knowledge acquired. It is evident that employees do not use their increased knowledge. However, we do not know why they do not use it. An enormous waste of money is spent on learning and knowledge in organisations which does not yield what is expected. How can managers act in order to enhance the application of increased knowledge possessed by the workforce?
Theoretical optical spectroscopy of complex systems
Conte, A. Mosca, E-mail: adriano.mosca.conte@roma2.infn.it [MIFP, NAST, ETSF,CNR INFM-SMC, Universitá di Roma Tor Vergata, Via della Ricerca Scientifica 1, Roma (Italy); Violante, C., E-mail: claudia.violante@roma2.infn.it [MIFP, NAST, ETSF,CNR INFM-SMC, Universitá di Roma Tor Vergata, Via della Ricerca Scientifica 1, Roma (Italy); Missori, M., E-mail: mauro.missori@isc.cnr.it [Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, Via Salaria Km 29.300, 00016 Monterotondo Scalo (Rome) (Italy); Bechstedt, F., E-mail: bech@ifto.physik.uni-jena.de [Institut fur Festkorpertheorie und -optik, Friedrich-Schiller-Universitat, Max-Wien-Platz 1, 07743 Jena (Germany); Teodonio, L. [MIFP, NAST, ETSF,CNR INFM-SMC, Universitá di Roma Tor Vergata, Via della Ricerca Scientifica 1, Roma (Italy); Istituto centrale per il restauro e la conservazione del patrimonio archivistico e librario (IC-RCPAL), Italian Minister for Cultural Heritage, Via Milano 76, 00184 Rome (Italy); Ippoliti, E.; Carloni, P. [German Research School for Simulation Sciences, Julich (Germany); Guidoni, L., E-mail: leonardo.guidoni@univaq.it [Università degli Studi di L’Aquila, Dipartimento di Chimica e Materiali, Via Campo di Pile, 67100 L’Aquila (Italy); Pulci, O., E-mail: olivia.pulci@roma2.infn.it [MIFP, NAST, ETSF,CNR INFM-SMC, Universitá di Roma Tor Vergata, Via della Ricerca Scientifica 1, Roma (Italy)
2013-08-15
Highlights: ► We review some theoretical condensed matter ab initio spectroscopic computational techniques. ► We show several applications ranging from 0 to 3 dimensional systems. ► For each system studied, we show which kind of information it is possible to obtain by performing these calculations. -- Abstract: We review here some of the most reliable and efficient computational theoretical ab initio techniques for the prediction of optical and electronic spectroscopic properties and show some important applications to molecules, surfaces, and solids. We investigate the role of the solvent in the optical absorption spectrum of indole molecule. We study the excited-state properties of a photo-active minimal model molecule for the retinal of rhodopsin, responsible for vision mechanism in animals. We then show a study about spectroscopic properties of Si(1 1 1) surface. Finally we simulate a bulk system: paper, that is mainly made of cellulose, a pseudo-crystalline material representing 40% of annual biomass production in the Earth.
Theoretical and computational analyses of LNG evaporator
Chidambaram, Palani Kumar; Jo, Yang Myung; Kim, Heuy Dong
2017-04-01
Theoretical and numerical analysis on the fluid flow and heat transfer inside a LNG evaporator is conducted in this work. Methane is used instead of LNG as the operating fluid. This is because; methane constitutes over 80% of natural gas. The analytical calculations are performed using simple mass and energy balance equations. The analytical calculations are made to assess the pressure and temperature variations in the steam tube. Multiphase numerical simulations are performed by solving the governing equations (basic flow equations of continuity, momentum and energy equations) in a portion of the evaporator domain consisting of a single steam pipe. The flow equations are solved along with equations of species transport. Multiphase modeling is incorporated using VOF method. Liquid methane is the primary phase. It vaporizes into the secondary phase gaseous methane. Steam is another secondary phase which flows through the heating coils. Turbulence is modeled by a two equation turbulence model. Both the theoretical and numerical predictions are seen to match well with each other. Further parametric studies are planned based on the current research.
Graph-theoretical concepts and physicochemical data
Lionello Pogliani
2003-02-01
Full Text Available Graph theoretical concepts have been used to model the molecular polarizabilities of fifty-four organic derivatives, and the induced dipole moment of a set of fifty-seven organic compounds divided into three subsets. The starting point of these modeling strategies is the hydrogen-suppressed chemical graph and pseudograph of a molecule, which works very well for second row atoms. From these types of graphs a set of graph-theoretical basis indices, the molecular connectivity indices, can be derived and used to model properties and activities of molecules. With the aid of the molecular connectivity basis indices it is then possible to build higher-order descriptors. The problem of 'graph' encoding the contribution of the inner-core electrons of heteroatoms can here be solved with the aid of odd complete graphs, Kp-(p-odd. The use of these graph tools allow to draw an optimal modeling of the molecular polarizabilities and a satisfactory modeling of the induced dipole moment of a wide set of organic derivatives.
Theoretical Basics of Teaching Discrete Mathematics
Y. A. Perminov
2012-01-01
Full Text Available The paper deals with the research findings concerning the process of mastering the theoretical basics of discrete mathematics by the students of vocational pedagogic profile. The methodological analysis is based on the subject and functions of the modern discrete mathematics and its role in mathematical modeling and computing. The modern discrete mathematics (i.e. mathematics of the finite type structures plays the important role in modernization of vocational training. It is especially rele- vant to training students for vocational pedagogic qualifications, as in the future they will be responsible for training the middle and the senior level specialists in engineer- ing and technical spheres. Nowadays in different industries, there arise the problems which require for their solving both continual – based on the classical mathematical methods – and discrete modeling. The teaching course of discrete mathematics for the future vocational teachers should be relevant to the target qualification and aimed at mastering the mathematical modeling, systems of computer mathematics and computer technologies. The author emphasizes the fundamental role of mastering the language of algebraic and serial structures, as well as the logical, algorithmic, combinatory schemes dominating in dis- crete mathematics. The guidelines for selecting the content of the course in discrete mathematics are specified. The theoretical findings of the research can be put into practice whilst developing curricula and working programs for bachelors and masters’ training.
Theoretical Division annual report, FY 1975. [LASL
Carruthers, P.A.
1976-02-01
This report presents an overview of the activities in the Theoretical Division and a summary of research highlights during FY 1975. It is intended to inform a wide audience about the theoretical work of the LASL and, therefore, contains introductory material which places recent advances in a broader context. The report is organized into two special interest reports: reactor safety research and the Advanced Research Committee, and 11 reports from the T-Division group leaders on the work of their respective groups. Main interests and responsibilities are outlined including the relationship of the group's work to the work of other T-Division groups and other divisions at the Laboratory. The description of research highlights for FY 1975 explains in a fairly simple, straightforward manner the major recent advances and their significance. Each group report is followed by a publication list for FY 1975 (330 references) and a list of talks given outside the Laboratory (140 references). 29 figures. (auth)
Electron microscopy and theoretical modeling of cochleates.
Nagarsekar, Kalpa; Ashtikar, Mukul; Thamm, Jana; Steiniger, Frank; Schacher, Felix; Fahr, Alfred; May, Sylvio
2014-11-11
Cochleates are self-assembled cylindrical condensates that consist of large rolled-up lipid bilayer sheets and represent a novel platform for oral and systemic delivery of therapeutically active medicinal agents. With few preceding investigations, the physical basis of cochleate formation has remained largely unexplored. We address the structure and stability of cochleates in a combined experimental/theoretical approach. Employing different electron microscopy methods, we provide evidence for cochleates consisting of phosphatidylserine and calcium to be hollow tubelike structures with a well-defined constant lamellar repeat distance and statistically varying inner and outer radii. To rationalize the relation between inner and outer radii, we propose a theoretical model. Based on the minimization of a phenomenological free energy expression containing a bending, adhesion, and frustration contribution, we predict the optimal tube dimensions of a cochleate and estimate ratios of material constants for cochleates consisting of phosphatidylserines with varied hydrocarbon chain structures. Knowing and understanding these ratios will ultimately benefit the successful formulation of cochleates for drug delivery applications.
Theoretical Models of the Galactic Bulge
Shen, Juntai; Li, Zhao-Yu
Near infrared images from the COBE satellite presented the first clear evidence that our Milky Way galaxy contains a boxy shaped bulge. Recent years have witnessed a gradual paradigm shift in the formation and evolution of the Galactic bulge. Bulges were commonly believed to form in the dynamical violence of galaxy mergers. However, it has become increasingly clear that the main body of the Milky Way bulge is not a classical bulge made by previous major mergers, instead it appears to be a bar seen somewhat end-on. The Milky Way bar can form naturally from a precursor disc and thicken vertically by the internal firehose/buckling instability, giving rise to the boxy appearance. This picture is supported by many lines of evidence, including the asymmetric parallelogram shape, the strong cylindrical rotation (i.e., nearly constant rotation regardless of the height above the disc plane), the existence of an intriguing X-shaped structure in the bulge, and perhaps the metallicity gradients. We review the major theoretical models and techniques to understand the Milky Way bulge. Despite the progresses in recent theoretical attempts, a complete bulge formation model that explains the full kinematics and metallicity distribution is still not fully understood. Upcoming large surveys are expected to shed new light on the formation history of the Galactic bulge.
Vapor Sensing Theoretical Study on Optical Microcavities
ZHANG Le-xin; ZHANG Ran; LI Zhi-quan
2007-01-01
When the organic vapors absorbed to the surface of porous silicon(PS), capillary condensation takes place due to the porous structure of the PS layer, accordingly resulting in the effective refractive index changing. For PS multi-layer microcavities, the different resonant peaks shift in the reflectivity spectrum of porous silicon microcavities(PSMs). The optical sensing model is set up by applying Bruggeman effective medium approximation theory, capillary condensation process and transfer matrix theoretically analytical method of one-dimensional photonic crystals. At the same time, comprehensively researched on are the sensing characteristics of PSMs which are exposed to give concentration organic vapors. At last, made is the theoretical simulation for sensing model of the PSMs in case of saturation by using computer numerical calculation, and found is the linearity relation between the refractive index of organic solvent and the peak-shift. At the same time deduced is the peak-shift as a function of the concentration of ethanol vapors.
A Theoretical Model of Water and Trade
Dang, Q.; Konar, M.; Reimer, J.; Di Baldassarre, G.; Lin, X.; Zeng, R.
2015-12-01
Water is an essential factor of agricultural production. Agriculture, in turn, is globalized through the trade of food commodities. In this paper, we develop a theoretical model of a small open economy that explicitly incorporates water resources. The model emphasizes three tradeoffs involving water decision-making that are important yet not always considered within the existing literature. One tradeoff focuses on competition for water among different sectors when there is a shock to one of the sectors only, such as trade liberalization and consequent higher demand for the product. A second tradeoff concerns the possibility that there may or may not be substitutes for water, such as increased use of sophisticated irrigation technology as a means to increase crop output in the absence of higher water availability. A third tradeoff explores the possibility that the rest of the world can be a source of supply or demand for a country's water-using products. A number of propositions are proven. For example, while trade liberalization tends to increase water use, increased pressure on water supplies can be moderated by way of a tax that is derivable with observable economic phenomena. Another example is that increased riskiness of water availability tends to cause water users to use less water than would be the case under profit maximization. These theoretical model results generate hypotheses that can be tested empirically in future work.
Information-theoretic metamodel of organizational evolution
Sepulveda, Alfredo
2011-12-01
Social organizations are abstractly modeled by holarchies---self-similar connected networks---and intelligent complex adaptive multiagent systems---large networks of autonomous reasoning agents interacting via scaled processes. However, little is known of how information shapes evolution in such organizations, a gap that can lead to misleading analytics. The research problem addressed in this study was the ineffective manner in which classical model-predict-control methods used in business analytics attempt to define organization evolution. The purpose of the study was to construct an effective metamodel for organization evolution based on a proposed complex adaptive structure---the info-holarchy. Theoretical foundations of this study were holarchies, complex adaptive systems, evolutionary theory, and quantum mechanics, among other recently developed physical and information theories. Research questions addressed how information evolution patterns gleamed from the study's inductive metamodel more aptly explained volatility in organization. In this study, a hybrid grounded theory based on abstract inductive extensions of information theories was utilized as the research methodology. An overarching heuristic metamodel was framed from the theoretical analysis of the properties of these extension theories and applied to business, neural, and computational entities. This metamodel resulted in the synthesis of a metaphor for, and generalization of organization evolution, serving as the recommended and appropriate analytical tool to view business dynamics for future applications. This study may manifest positive social change through a fundamental understanding of complexity in business from general information theories, resulting in more effective management.
Theoretical Study on Standing Wave Thermoacoustic Engine
Kalra, S.; Desai, K. P.; Naik, H. B.; Atrey, M. D.
Applications of thermoacoustic engines are not limited to driving pulse tube cryocoolers. The performance of a thermoacoustic engine is governed by various design parameters like type of resonator, stack geometry, frequency, type of working gas etc. and various operating parameters like heat input, charging pressure etc. It is very important to arrive at an optimum configuration of the engine for which a theoretical model is required. In the present work, a theoretical analysis, based on linear acoustic theory of a standing wave type half wavelength thermoacoustic engine is carried out using DeltaEC software. The system dimensions like length of resonator, stack, hot and cold heat exchangers are fixed with a helium-argon mixture as the working gas and a parallel plate type stack. Later on, two plate spacings, corresponding to helium-argon mixture and nitrogen gas, are used for carrying out analysis with helium, argon, nitrogen, carbon dioxide and helium-argon mixture as working gases of the system. The effect of charging pressure on the performance of the system is studied in terms of resonating frequency, onset temperature, pressure amplitude, acoustic power and efficiency. The conclusions derived from the analysis are reported in the paper.
Theoretical and practical significance of formal reasoning
Linn, Marcia C.
Piaget's theory has profoundly influenced science education research. Following Piaget, researchers have focused on content-free strategies, developmentally based mechanisms, and structural models of each stage of reasoning. In practice, factors besides those considered in Piaget's theory influence whether or not a theoretically available strategy is used. Piaget's focus has minimized the research attention placed on what could be called practical factors in reasoning. Practical factors are factors that influence application of a theoretically available strategy, for example, previous experience with the task content, familiarity with task instructions, or personality style of the student. Piagetian theory has minimized the importance of practical factors and discouraged investigation of (1) the role of factual knowledge in reasoning, (2) the diagnosis of specific, task-based errors in reasoning, (3) the influence of individual aptitudes on reasoning (e.g., field dependence-independence), and (4) the effect of educational interventions designed to change reasoning. This article calls for new emphasis on practical factors in reasoning and suggests why research on practical factors in reasoning will enhance our understanding of how scientific reasoning is acquired and of how science education programs can foster it.
A theoretical derivation of the HoekeBrown failure criterion for rock materials
Jianping Zuo; Huihai Liu; Hongtao Li
2015-01-01
This study uses a three-dimensional crack model to theoretically derive the HoekeBrown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor needs to exceed a critical value when macro-failure occurs. This factor is a product of the micro-failure orientation angle (characterizing the density and orientation of damaged micro-cracks) and the changing rate of the angle with respect to the major principal stress (characterizing the microscopic stability of damaged cracks). We further demonstrate that the factor mathematically leads to the empirical HoekeBrown rock failure criterion. Thus, the proposed factor is able to successfully relate the evolution of microscopic damaged crack characteristics to macro-failure. Based on this theoretical development, we also propose a quantitative relationship between the brittleeductile transition point and confining pressure, which is consistent with experimental observations.
Economic Growth of a Rapidly Developing Economy: Theoretical Formulation
Oleg Sergeyevich Sukharev
2016-06-01
Full Text Available The subject matter of the article is the description of economic growth. Modern economy is characterized by a high rate of changes. These changes are the limiting parameters of modern development, which requires a modification of the basic models of growth, the substantiation of the expediency and necessity of a rapid development strategy. In a simple mathematical form, the statement of the problem of economic growth in the “green economy” is examined, in which the costs of environmental measures are not considered a priori as hampering economic development (as it is common for a number of modern neoclassical and neo-Keynesian growth models. The methodological basis of the article are the econometric approach and modelling method. The article has a theoretical character. The main hypothesis supposes that the rapid development strategy cannot make an adequate development strategy under certain conditions, but may be acceptable in other its specific conditions. In this sense, the important growth conditions are the availability of resources, the effectiveness of institutions and the current economic structure, the technological effectiveness of economy, as well as the conditions of technological development (“green economy” and the path of such development. In the article, on the theoretical level of analysis, the substantiation of the adequacy of the rapid development strategy for an economic system is given, whose goal is to achieve the standard of living of the countryleader. Based on the assumptions introduced, the period for which the rapid development strategy might be implemented and the economic lag of the country might be reduced from the country-leader is determined. The conditions that ensure the impact of innovations on the rate of economic development are summarized. The introduced range of dependencies and relations can be useful for the elaboration of the theory of innovation development and for the formation of a new
A Theoretical Model for Selective Exposure Research.
Roloff, Michael E.; Noland, Mark
This study tests the basic assumptions underlying Fishbein's Model of Attitudes by correlating an individual's selective exposure to types of television programs (situation comedies, family drama, and action/adventure) with the attitudinal similarity between individual attitudes and attitudes characterized on the programs. Twenty-three college…
The Neurobiology of Autism: Theoretical Applications
Schroeder, Jessica H.; Desrocher, Mary; Bebko, James M.; Cappadocia, M. Catherine
2010-01-01
Autism spectrum disorders (ASD) are complex neurological disorders characterized by heterogeneity in skills and impairments. A variety of models have been developed to describe the disorders and a wide range of brain processes have been implicated. This review attempts to integrate some of the consistent neurological findings in the research with…
Group-Theoretical Aspects of Instantons
Meyers, C.; Roo, M. de; Sorba, P.
1979-01-01
We discuss the problem of embeddings in non-Abelian gauge theories. The (ir)redueibility of a gauge field configuration is characterized. For the specific case of instanton solutions we derive a practical criterion for SUn. In the general construction of self-dual solutions the reducibility of the
Group-Theoretical Aspects of Instantons
Meyers, C.; Roo, M. de; Sorba, P.
1979-01-01
We discuss the problem of embeddings in non-Abelian gauge theories. The (ir)redueibility of a gauge field configuration is characterized. For the specific case of instanton solutions we derive a practical criterion for SUn. In the general construction of self-dual solutions the reducibility of the g
Antoniak Jerzy
2003-09-01
Full Text Available Theoretical basis used to build new generation of belt conveyors is presented is this paper. These conveyors are characterized by better energy-saving parameters of the transport of run-of-mine and higher reliability. Examples of current technical solutions applied in coal mines have been used to present the results of this research. The paper is summarized with conclusions and remarks.
Theoretical Research Program on Bio-inspired Inorganic Hydrogen Generating Catalysts and Electrodes
Selloni, Annabella; Car, Roberto; Cohen, Morrel H.
2014-04-17
In this project, we have successfully designed and characterized a promising biomimetic catalyst/electrode complex, [FeFe]P/FeS2 for producing hydrogen from water. It is comprised of earth-abundant materials and, with a diffusion-limited rate in acidified water, is efficient as well as oxygen tolerant. The theoretical techniques we have developed and the experience we have gained are broadly applicable for the design and analysis of biomimetic electrochemically active catalysts.
Famini, George R; Aguiar, Denise; Payne, Marvin A; Rodriquez, Ryan; Wilson, Leland Y
2002-01-01
The theoretical linear solvation energy relationship (TLSER) has been used to correlate and characterize 44 nasal pungency threshold (NPT) values in man with parameters derived from semi-empirical molecular orbital theory. The resulting relationship provides good correlative (R2 > 0.92) and predictive (R2cy > 0.88) capability. In addition, the TLSER parameters are used as a molecular probe to attempt to understand the fundamental properties influencing nasal pungency.
Stefanik A.
2015-06-01
Full Text Available Technology of round bars rolling on a three-high skew rolling mills allows rolling of standard materials such as steel and aluminum, as well as new materials, especially hard deformable materials. The paper presents the results of theoretical and experimental rolling process of aluminum bars with a diameter of 20 mm. As the stock round bars with a diameter of 25 mm made of aluminum grade 1050A and aluminum alloy grade 2017A were used. The rolling process of aluminum bars has been carried out in a single pass. The numerical analysis was carried out by using computer program Forge2011®. On the basis of theoretical research it has been determined the state of deformation, stress and temperature distribution during rolling of aluminum bars. In addition, the results of theoretical research allowed to determine the schema of the metal plastic flow in the roll gap. Verification of the theoretical research was carried out during the rolling of aluminum bars on the RSP 40/14 laboratory three-high skew rolling mill. From the finished bars were taken the samples to set the shape and compared with the results of theoretical research. Finished aluminum round bars were characterized by low ovality and good surface quality.
Theoretical studies on aerosol agglomeration processes
Lehtinen, K.E.J. [VTT Energy, Espoo (Finland). Energy Use
1997-12-31
In this thesis, theoretical modeling of certain aerosol systems has been presented. At first, the aerosol general dynamic equation is introduced, along with a discretization routine for its numerical solution. Of the various possible phenomena affecting aerosol behaviour, this work is mostly focused on aerosol agglomeration. The fundamentals of aerosol agglomeration theory are thus briefly reviewed. The two practical applications of agglomeration studied in this thesis are flue gas cleaning using an electrical agglomerator and nanomaterial synthesis with a free jet reactor. In an electrical agglomerator the aerosol particles are charged and brought into an alternating electric field. The aim is to remove submicron particles from flue gases by collisions with larger particles before conventional gas cleaning devices that have a clear penetration window in the problematic 0.1-1{mu}m size range. A mathematical model was constructed to find out the effects of the different system parameters on the agglomerator`s performance. A crucial part of this task was finding out the collision efficiencies of particles of varying size and charge. The original idea was to use unipolar charging of the particles, and a laboratory scale apparatus was constructed for this purpose. Both theory and experiments clearly show that significant removal of submicron particles can not be achieved by such an arrangement. The theoretical analysis further shows that if the submicron particles and the large collector particles were charged with opposite polarity, significant removal of the submicron particles could be obtained. The second application of agglomeration considered in this thesis is predicting/controlling nanoparticle size in the gas-to-particle aerosol route to material synthesis. In a typical material reactor, a precursor vapor reacts to form molecules of the desired material. In a cooling environment, a particulate phase forms, the dynamics of which are determined by the rates of
Theoretical analysis of the state of balance in bipedal walking.
Firmani, Flavio; Park, Edward J
2013-04-01
This paper presents a theoretical analysis based on classic mechanical principles of balance of forces in bipedal walking. Theories on the state of balance have been proposed in the area of humanoid robotics and although the laws of classical mechanics are equivalent to both humans and humanoid robots, the resulting motion obtained with these theories is unnatural when compared to normal human gait. Humanoid robots are commonly controlled using the zero moment point (ZMP) with the condition that the ZMP cannot exit the foot-support area. This condition is derived from a physical model in which the biped must always walk under dynamically balanced conditions, making the centre of pressure (CoP) and the ZMP always coincident. On the contrary, humans follow a different strategy characterized by a 'controlled fall' at the end of the swing phase. In this paper, we present a thorough theoretical analysis of the state of balance and show that the ZMP can exit the support area, and its location is representative of the imbalance state characterized by the separation between the ZMP and the CoP. Since humans exhibit this behavior, we also present proof-of-concept results of a single subject walking on an instrumented treadmill at different speeds (from slow 0.7 m/s to fast 2.0 m/s walking with increments of 0.1 m/s) with the motion recorded using an optical motion tracking system. In order to evaluate the experimental results of this model, the coefficient of determination (R2) is used to correlate the measured ground reaction forces and the resultant of inertial and gravitational forces (anteroposterior R² = 0.93, mediolateral R² = 0.89, and vertical R² = 0.86) indicating that there is a high correlation between the measurements. The results suggest that the subject exhibits a complete dynamically balanced gait during slow speeds while experiencing a controlled fall (end of swing phase) with faster speeds. This is quantified with the root-mean-square deviation (RMSD
The mystery of regional unemployment differentials : Theoretical and empirical explanations
Elhorst, JP
2003-01-01
This paper provides an integrated overview of theoretical and empirical explanations used in the applied literature on regional unemployment differentials. On the basis of 41 empirical studies, four different model types covering nine theoretical constructs of regional unemployment determination and
Theoretical study of conjugated porphyrin polymers
Pedersen, T.G.; Lynge, T.B.; Kristensen, P.K.
2005-01-01
The optical gap of conjugated triply linked porphyrin chains is exceptionally low (similar to 0.5 eV). Hence, such chains are candidates for organic infrared detectors and solar cells harvesting the infrared part of the solar spectrum. However, a low exciton binding energy is required for these a......The optical gap of conjugated triply linked porphyrin chains is exceptionally low (similar to 0.5 eV). Hence, such chains are candidates for organic infrared detectors and solar cells harvesting the infrared part of the solar spectrum. However, a low exciton binding energy is required...... for these applications. From a theoretical analysis of excitons in long metalloporphyrin chains, we demonstrate that the binding energy is much lower than in usual conjugated polymers. Our calculated absorption spectra are in good agreement with measurements. (c) 2004 Elsevier B.V. All rights reserved....
Game Theoretic Methods for the Smart Grid
Saad, Walid; Poor, H Vincent; Başar, Tamer
2012-01-01
The future smart grid is envisioned as a large-scale cyber-physical system encompassing advanced power, communications, control, and computing technologies. In order to accommodate these technologies, it will have to build on solid mathematical tools that can ensure an efficient and robust operation of such heterogeneous and large-scale cyber-physical systems. In this context, this paper is an overview on the potential of applying game theory for addressing relevant and timely open problems in three emerging areas that pertain to the smart grid: micro-grid systems, demand-side management, and communications. In each area, the state-of-the-art contributions are gathered and a systematic treatment, using game theory, of some of the most relevant problems for future power systems is provided. Future opportunities for adopting game theoretic methodologies in the transition from legacy systems toward smart and intelligent grids are also discussed. In a nutshell, this article provides a comprehensive account of the...
Magnetic Reconnection: Theoretical and Observational Perspectives: Preface
Lewis, W. S.; Antiochos, S. K,; Drake, J. F.
2011-01-01
Magnetic reconnection is a fundamental plasma-physical process by which energy stored in a magnetic field is converted, often explosively, into heat and the kinetic energy of the charged particles that constitute the plasma. It occurs in a variety of astrophysical settings, ranging from the solar corona to pulsar magnetospheres and winds, as well as in laboratory fusion experiments, where it is responsible for sawtooth crashes. First proposed by R.G. Giovanelli in the late I 940s as the mechanism responsible for solar flares, magnetic reconnection was invoked at the beginning of the space age to explain not just solar flares but also the transfer of energy, mass, and momentum from the solar wind to Earth's magnetosphere and the subsequent storage and release of the transferred energy in the magnetotai\\. During the half century or so that has followed the seminal theoretical works by J.W. Dungey, P.A. Sweet, E.N. Parker, and H.E. Petschek, in-situ measurements by Earth-orbiting satellites and remote-sensing observations of the solar corona have provided a growing body of evidence for the occurrence of reconnection at the Sun, in the solar wind, and in the near-Earth space environment. The last thirty years have also seen the development of laboratory reconnection experiments at a number of institutions. In parallel with the efforts of experimentalists in both space and laboratory plasma physics, theorists have investigated, analytically and with the help of increasingly powerful MHD, hybrid, and kinetic numerical simulations, the structure of the diffusion region, the factors controlling the rate, onset, and cessation of reconnection, and the detailed physics that enables the demagnetization of the ions and electrons and the topological reconfiguration of the magnetic field. Moreover, the scope of theoretical reconnection studies has been extended well beyond solar system and laboratory plasmas to include more exotic astrophysical plasma systems whose strong (10
POSITIVE LEADERSHIP MODELS: THEORETICAL FRAMEWORK AND RESEARCH
Javier Blanch, Francisco Gil
2016-09-01
Full Text Available The objective of this article is twofold; firstly, we establish the theoretical boundaries of positive leadership and the reasons for its emergence. It is related to the new paradigm of positive psychology that has recently been shaping the scope of organizational knowledge. This conceptual framework has triggered the development of the various forms of positive leadership (i.e. transformational, servant, spiritual, authentic, and positive. Although the construct does not seem univocally defined, these different types of leadership overlap and share a significant affinity. Secondly, we review the empirical evidence that shows the impact of positive leadership in organizations and we highlight the positive relationship between these forms of leadership and key positive organizational variables. Lastly, we analyse future research areas in order to further develop this concept.
From Disks To Planets: A Theoretical Perspective
Bromley, Ben
2016-07-01
Circumstellar disks of gas and dust naturally produce planets. Observations of young stellar systems tell us the starting conditions, while planet surveys reveal an amazing diversity of outcomes. Theory tries to connect the dots with ideas on how planets emerge from dust within an evolving gas disk. Here I give a broad-brush view of planet formation from a theoretical perspective, noting recent ideas and successes. I also consider the challenges. The conversion of primordial dust into planetesimals is uncertain. Even the mass budget in solids is a problem, since the total mass in dust observed around young stars seems insufficient to account for the census of full-fledged planets. Toward resolving these issues, the Atacama Large Millimeter Array and the Karl G. Jansky Very Large Array are playing key roles in illuminating how disks become planets.
Theoretical study of the NO beta system
Langhoff, Stephen R.; Partridge, Harry; Bauschlicher, Charles W., Jr.; Komornicki, Andrew
1991-01-01
A theoretical determination of the transition moment functions (TMFs) for the beta system of NO is presented. High levels of correlation treatment are required to show the changing degree of Rydberg character in the B2II with decreasing r values. The state-averaged complete-active-space self-consistent-field multireference configuration-interaction method is used for the determination. Previous lifetime measurements made with laser-induced fluorescence, varying between 2 and 0.85 microns, are discussed in terms of the calculated lifetimes for v-prime values 0-6, which vary from 2.12-1.17 microns. When larger r values are used for the transition moment function, the calculated lifetimes correlate with experimental lifetimes. The Einstein coefficients agree with experimental results, although limitations in the calibration of the spectrometer can account for systematic differences. The correlation with earlier experimental results suggests that radiative lifetimes are in the range of 1-2 microns.
Advertising Graphic Design: theoretical and methodological foundations
Antonovych, Y.; Pryshchenko, S.
2016-01-01
The article deals with the authors theoretical and methodological foundations to the forming of an actual educational discipline «Ad Graphic Design» as integration of graphic design, advertising and marketing. Basic components of the professionalism of a designer in advertising have been selected taking into account the requirements of modern market: graphic design-foundation, sociological and marketing components. В статье рассмотрены разработанные авторами теоретико-методологические осно...
Theoretical study on spherical proton emission
无
2009-01-01
The proton radioactivity half-lives of spherical proton emitters are investigated within a generalized liquid drop model(GLDM),including the proximity effects between nuclei in a neck and the mass and charge asymmetry.The penetrability is calculated in the WKB approximation and the assault frequency is estimated by the quantum mechanism method considering the structure of the parent nucleus.The spectroscopic factor is taken into account in half-life calculation,which is obtained by employing the relativistic mean field(RMF) theory.The half-lives within the GLDM are compared with the experimental data and other theoretical values.The results show that the GLDM works quite well for spherical proton emitters when the assault frequency is estimated by the quantum mechanical method and the spectroscopic factor is considered.
Theoretical mechanics an introduction to mathematical physics
Sweetman Ames, Joseph
1958-01-01
In this book Professors Ames and Murnaghan undertake a mathematically rigorous development of theoretical mechanics from the point of view of modern physics. It gives an intensive survey of this basis field with extensive and extremely thorough discussions of vector and tensor methods, the displacement and motion of a rigid body, dynamics of inertial and non-inertial reference frames, dynamics of a particle, harmonic vibrations, nonrectilinear motion of a particle, central forces and universal gravitation, dynamics of a systems of material particle,impulsive forces, motion of a rigid body about a fixed point, gyroscopic and barygyroscopic theory, general dynamical theorems, vibrations about a point of equilibrium, the principle of least action, holonomic and nonholonomic systems, the principle of least constraint, general methods of integration and the three body problem, the potential function (including simple-layer and double-layer potentials), wave motion, the Lorentz-Einstein transformation and an illumi...
Theoretical study on spherical proton emission
ZHANG HongFei; WANG YongJia; DONG JianMin; LI JunQing
2009-01-01
The proton radioactivity half-lives of spherical proton emitters are investigated within a generalized liquid drop model (GLDM),including the proximity effects between nuclei in a neck and the mass and charge asymmetry.The penetrability is calculated in the WKB approximation and the assault frequency is estimated by the quantum mechanism method considering the structure of the parent nucleus.The spectroscopic factor is taken into account in half-life calculation,which is obtained by employing the relativistic mean field (RMF) theory.The half-lives within the GLDM are compared with the experimental data and other theoretical values.The results show that the GLDM works quite well for spherical proton emitters when the assault frequency is estimated by the quantum mechanical method and the spectroscopic factor is considered.
Producing Films, Producing Meanings: Some Theoretical Reflections
Giorgio Grignaffini
2015-01-01
Full Text Available The article aims to stimulate greater attention by semiotics of cinema upon production practices and preparatory materials for the film, as yet not so much studied compared to the dynamics that the texts themselves activate on the audiences. This proposed extension of the field of research, is thorough in its theoretical premises in two phases. First is contextualized in relation to the practice of "traditional" semiotic analysis; then, using the semiotic tools developed by Eric Landowski, in particular by exploiting the concept of "adjustment" developed in the framework of reflection on how subjects interact, are highlighted fields of application (e.g. the work of the directors with the actors and heuristic potential benefits.
Theoretical Considerations in Developing Amorphous Solid Dispersions
Laitinen, Riikka; Priemel, Petra Alexandra; Surwase, Sachin;
2014-01-01
Before pursuing the laborious route of amorphous solid dispersion formulation and development, which is the topic of many of the subsequent chapters in this book, the formulation scientist would benefit from a priori knowledge whether the amorphous route is a viable one for a given drug and how...... to their glass-forming ability and glass stability. In the main parts of this chapter, we review theoretical approaches to determine amorphous drug polymer miscibility and crystalline drug polymer solubility, as a prerequisite to develop amorphous solid dispersions (glass solutions)....... much solubility improvement, and hence increase in bioavailability, can be expected, and what forms of solid dispersion have been developed in the past. In this chapter, we therefore initially define the various forms of solid dispersions, and then go on to discuss properties of pure drugs with respect...
Theoretical physics 6 quantum mechanics : basics
Nolting, Wolfgang
2017-01-01
This textbook offers a clear and comprehensive introduction to the basics of quantum mechanics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, thus developing the physical understanding further on to quantized states. The first part of the book introduces wave equations while exploring the Schrödinger equation and the hydrogen atom. More complex themes are covered in the second part of the book, which describes the Dirac formulism of quantum mechanics. Ideally suited to undergraduate students with some grounding in classical mechanics and electrodynamics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this...
Theoretical Priors On Modified Growth Parametrisations
Song, Yong-Seon; Caldera-Cabral, Gabriela; Koyama, Kazuya
2010-01-01
Next generation surveys will observe the large-scale structure of the Universe with unprecedented accuracy. This will enable us to test the relationships between matter over-densities, the curvature perturbation and the Newtonian potential. Any large-distance modification of gravity or exotic nature of dark energy modifies these relationships as compared to those predicted in the standard smooth dark energy model based on General Relativity. In linear theory of structure growth such modifications are often parameterised by virtue of two functions of space and time that enter the relation of the curvature perturbation to, first, the matter over-density, and second, the Newtonian potential. We investigate the predictions for these functions in Brans-Dicke theory, clustering dark energy models and interacting dark energy models. We find that each theory has a distinct path in the parameter space of modified growth. Understanding these theoretical priors on the parameterisations of modified growth is essential to...
Aromatherapy and nursing: historical and theoretical conception
Juliana Rizzo Gnatta
2016-02-01
Full Text Available Abstract Aromatherapy is a Practical or Complementary Health Therapy that uses volatile concentrates extracted from plants called essential oils, in order to improve physical, mental and emotional well-being. Aromatherapy has been practiced historically and worldwide by nurses and, as in Brazil is supported by the Federal Nursing Council, it is relevant to discuss this practice in the context of Nursing through Theories of Nursing. This study of theoretical reflection, exploratory and descriptive, aims to discuss the pharmacognosy of essential oils, the historical trajectory of Aromatherapy in Nursing and the conceptions to support Aromatherapy in light of eight Nursing Theorists (Florence Nightingale, Myra Levine, Hildegard Peplau, Martha Rogers, Callista Roy, Wanda Horta, Jean Watson and Katharine Kolcaba, contributing to its inclusion as a nursing care practice.
[Aromatherapy and nursing: historical and theoretical conception].
Gnatta, Juliana Rizzo; Kurebayashi, Leonice Fumiko Sato; Turrini, Ruth Natalia Teresa; Silva, Maria Júlia Paes da
2016-02-01
Aromatherapy is a Practical or Complementary Health Therapy that uses volatile concentrates extracted from plants called essential oils, in order to improve physical, mental and emotional well-being. Aromatherapy has been practiced historically and worldwide by nurses and, as in Brazil is supported by the Federal Nursing Council, it is relevant to discuss this practice in the context of Nursing through Theories of Nursing. This study of theoretical reflection, exploratory and descriptive, aims to discuss the pharmacognosy of essential oils, the historical trajectory of Aromatherapy in Nursing and the conceptions to support Aromatherapy in light of eight Nursing Theorists (Florence Nightingale, Myra Levine, Hildegard Peplau, Martha Rogers, Callista Roy, Wanda Horta, Jean Watson and Katharine Kolcaba), contributing to its inclusion as a nursing care practice.
Theoretical model of a photoelectrochemical solar cell
Chandra, S.; Singh, S.L.; Khare, N.
1986-03-01
A Schottky barrier theoretical model for explaining the J-V characteristic of a photoelectrochemical solar cell (PESC) has been developed considering the effect of dark current, space-charge recombination, surface states, and detailed charge transfer kinetics at the interface. Both isoenergetic charge transfer and inelastic charge transfers (via surface states) at the interface have been considered and their relative importance are discussed. The theory has been applied to explain the (a) J-V characteristic for n-GaAs/SeS , SeS 2 junction and (b) Fermi-level pinning observed in GaAs PESC. The inelastic charge transfer via surfaces states has been shown to play an important role in deciding these characteristics.
The Janus fluid a theoretical perspective
Fantoni, Riccardo
2013-01-01
The state-of-the-art in the theoretical statistical physics treatment of the Janus fluid is reported with a bridge between new research results published in journal articles and a contextual literature review. Recent Monte Carlo simulations on the Kern and Frenkel model of the Janus fluid have revealed that in the vapor phase, below the critical point, there is the formation of preferred inert clusters made up of a well-defined number of particles: the micelles and the vesicles. This is responsible for a re-entrant gas branch of the gas-liquid binodal. Detailed account of this findings are given in the first chapter where the Janus fluid is introduced as a product of new sophisticated synthesis laboratory techniques. In the second chapter a cluster theory is developed to approximate the exact clustering properties stemming from the simulations. It is shown that the theory is able to reproduce semi-quantitatively the micellization phenomenon.
Courcelle's Theorem - A Game-Theoretic Approach
Kneis, Joachim; Rossmanith, Peter
2011-01-01
Courcelle's Theorem states that every problem definable in Monadic Second-Order logic can be solved in linear time on structures of bounded treewidth, for example, by constructing a tree automaton that recognizes or rejects a tree decomposition of the structure. Existing, optimized software like the MONA tool can be used to build the corresponding tree automata, which for bounded treewidth are of constant size. Unfortunately, the constants involved can become extremely large - every quantifier alternation requires a power set construction for the automaton. Here, the required space can become a problem in practical applications. In this paper, we present a novel, direct approach based on model checking games, which avoids the expensive power set construction. Experiments with an implementation are promising, and we can solve problems on graphs where the automata-theoretic approach fails in practice.
Theoretical foundations of the chronometric cosmology.
Segal, I E
1976-03-01
The derivation of the redshift (z)-distance (r) relation in the chronometric theory of the Cosmos is amplified. The basic physical quantities are represented by precisely defined self-adjoint operators in global Hilbert spaces. Computations yielding explicit bounds for the deviation of the theoretical prediction from the relation z = tan(2)(r/2R) (where R denotes the radius of the universe), earlier derived employing less formal procedures, are carried out for: (a) a cut-off plane wave in two dimensions; (b) a scalar spherical wave in four dimensions; (c) the same as (b) with appropriate incorporation of the photon spin. Both this deviation and the (quantum) dispersion in redshift are shown to be unobservably small. A parallel classical treatment is possible and leads to similar results.
Theoretical discussions on the geometrical phase analysis
Rouviere, J.L. [CEA-Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, SP2M, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)]. E-mail: rouvierej@cea.fr; Sarigiannidou, E. [CEA-Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, SP2M, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)
2005-12-15
The Geometrical phase analysis, which is a very efficient method to measure deformation from High resolution transmission electron microscopy images, is studied from a theoretical point of view. We point out that the basic property of this method is its ability to measure local reciprocal lattice parameters with a high level of accuracy. We attempt to provide some insights into (a) different formula used in the geometrical phase analysis such as the well-known relation between phase and displacement: P{sub g}(r)=-2{pi}g.u(r), (b) the two different definitions of strain, each of which corresponding to a different lattice reference and (c) the meaning of a continuous displacement in a dot-like high resolution image. The case of one-dimensional analysis is also presented. Finally, we show that the method is able to give the position of the dot that is nearest to a given pixel in the image.
Intermittency in Switching Power Converters: Theoretical Analysis
ZHOU Yu-fei; CHEN Jun-ning; TSE Chi K.; QIU Shui-sheng; KE Dao-ming; SHI Long-xing; SUN Wei-feng
2006-01-01
In view of reasonable explanation of intermittent subharmonics and chaos that can be gained from coupling filter between circuits,this paper discusses a method that maps time bifurcation with parameter bifurcation.Based on this mapping method,the general analysis method of characteristic multiplier,which is originally aimed at parameter bifurcation,can be used for the study of intermittency,i.e.,time bifurcation.In this paper,all researches coming from characteristic multipliers,parameter-bifurcation diagrams,and the largest Lyapunov exponent indicate the same results as those produced by simulation and experiment.Thus,it is proved theoretically that the intermittency in switching power converter can be explained in terms of coupling of spurious interference.
Theoretical and methodological approaches in discourse analysis.
Stevenson, Chris
2004-10-01
Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power. Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a frame- work for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.
Theoretical research on aggregative dynamic pressure damper
HU Jun-hua; CAO Shu-ping; LUO Xiao-hui; NIU Zi-hua; XIN Ji-song
2009-01-01
To broaden the frequency width and increase the damping coefficient of a dynamic pressure damper, we designed an aggregative dynamic pressure damper (ADPD). Combined with the advantages of traditional dynamic pressure dampers (TDPD), ADPD can not only increase the damping coefficient in wide frequency range for valve control system, but also absorb partial pressure pulsations and impacts in the low and high frequency fields. Based on the theoretical research and the analysis compared with TDPD, we concluded that the ADPD was superior to the TDPD in the middle high frequency field, and the main parameters influencing the performance of the damper were the damping stiffness, orifice flow coefficient, pre-charge pressure, and the volume of the damper accumulator.
A decision theoretical approach for diffusion promotion
Ding, Fei; Liu, Yun
2009-09-01
In order to maximize cost efficiency from scarce marketing resources, marketers are facing the problem of which group of consumers to target for promotions. We propose to use a decision theoretical approach to model this strategic situation. According to one promotion model that we develop, marketers balance between probabilities of successful persuasion and the expected profits on a diffusion scale, before making their decisions. In the other promotion model, the cost for identifying influence information is considered, and marketers are allowed to ignore individual heterogeneity. We apply the proposed approach to two threshold influence models, evaluate the utility of each promotion action, and provide discussions about the best strategy. Our results show that efforts for targeting influentials or easily influenced people might be redundant under some conditions.
Operator theoretic aspects of ergodic theory
Eisner, Tanja; Haase, Markus; Nagel, Rainer
2015-01-01
Stunning recent results by Host–Kra, Green–Tao, and others, highlight the timeliness of this systematic introduction to classical ergodic theory using the tools of operator theory. Assuming no prior exposure to ergodic theory, this book provides a modern foundation for introductory courses on ergodic theory, especially for students or researchers with an interest in functional analysis. While basic analytic notions and results are reviewed in several appendices, more advanced operator theoretic topics are developed in detail, even beyond their immediate connection with ergodic theory. As a consequence, the book is also suitable for advanced or special-topic courses on functional analysis with applications to ergodic theory. Topics include: •an intuitive introduction to ergodic theory •an introduction to the basic notions, constructions, and standard examples of topological dynamical systems •Koopman operators, Banach lattices, lattice and algebra homomorphisms, and the Gelfand–Naimark theorem •m...
Quantum speed problem: Theoretical hints for control
Lisboa, Alexandre Coutinho; Piqueira, José Roberto Castilho
2016-06-01
The transition time between states plays an important role in designing quantum devices as they are very sensitive to environmental influences. Decoherence phenomenon is responsible for possible destructions of the entanglement that is a fundamental requirement to implement quantum information processing systems. If the time between states is minimized, the decoherence effects can be reduced, thus, it is advantageous to the designer to develop expressions for time performance measures. Quantum speed limit (QSL) problem has been studied from the theoretical point of view, providing general results. Considering the implementation of quantum control systems, as the decoherence phenomenon is unavoidable, it is important to apply these general results to particular cases, developing expressions and performance measures, to assist control engineering designers. Here, a minimum time performance measure is defined for quantum control problems, for time-independent or time-dependent Hamiltonians, and applied to some practical examples, providing hints that may be useful for researchers pursuing optimization strategies for quantum control systems.
Analysis of a theoretically optimized transonic airfoil
Lores, M. E.; Burdges, K. P.; Shrewsbury, G. D.
1978-01-01
Numerical optimization was used in conjunction with an inviscid, full potential equation, transonic flow analysis computer code to design an upper surface contour for a conventional airfoil to improve its supercritical performance. The modified airfoil was tested in a compressible flow wind tunnel. The modified airfoil's performance was evaluated by comparison with test data for the baseline airfoil and for an airfoil developed by optimization of leading edge of the baseline airfoil. While the leading edge modification performed as expected, the upper surface re-design did not produce all of the expected performance improvements. Theoretical solutions computed using a full potential, transonic airfoil code corrected for viscosity were compared to experimental data for the baseline airfoil and the upper surface modification. These correlations showed that the theory predicted the aerodynamics of the baseline airfoil fairly well, but failed to accurately compute drag characteristics for the upper surface modification.
Property Testing via Set-Theoretic Operations
Chen, Victor; Xie, Ning
2010-01-01
Given two testable properties $\\mathcal{P}_{1}$ and $\\mathcal{P}_{2}$, under what conditions are the union, intersection or set-difference of these two properties also testable? We initiate a systematic study of these basic set-theoretic operations in the context of property testing. As an application, we give a conceptually different proof that linearity is testable, albeit with much worse query complexity. Furthermore, for the problem of testing disjunction of linear functions, which was previously known to be one-sided testable with a super-polynomial query complexity, we give an improved analysis and show it has query complexity $O(1/\\eps^2)$, where $\\eps$ is the distance parameter.
Theoretical and Legal Reflections on Securities Dispositions
Holub Dušan
2015-09-01
Full Text Available Decreasing the number of materialised securities for the benefit of electronic securities has led to distinctions between commercial and legal opinions on securities transactions. Contemporary financial markets only trade electronic securities held in securities accounts. Securities law enhances adjustments to economic realities and not to legal principles. Discrepancies between economic realities and securities regulation should be resolved in order to find a balance between successfully functioning transactions of electronic securities and legal schemes which are based on transfers of physically existing assets, which include securities, as a result of the theory of incorporations, in certain legal regulations. This article is a theoretical and legal reflection on selected issues connected with the transfer of securities with reference to discrepancies between economic realities and legal regulations.
Theoretical, regulatory and practical implications of logistics
Mirosław Chaberek
2014-03-01
Full Text Available Background: The logistics has its practical input in creating economical strategies as well as in creating modern economic environment. Processes of planning, designing and functioning of logistic systems must be based both on the theoretical knowledge covering various areas as well as practical experiences to provide the required support. To provide logistic services in the rational way, it is necessary to learn the complicated set of implications resulting from three areas covering the theoretical knowledge, practical ones as well as the regulation by the law. Methods: The triad of three concepts: theory, practice and regulation is the main area of consideration in relation to tasks of the logistic support provided by any organization for any production process. The aim of this paper focuses on the necessity of taking into account implications among theory, practice and regulation during the process of analyzing, designing and implementation of systems of the logistic support. The lack of awareness of differences between various implications or ignoring them must lead to irrational behaviors. Results: The implications among theory, practice and legislative regulation of logistics presented differently than usually, broaden the logistic knowledge and at the same time provide the tool of the rationalization of logistic services in all kinds of activities. Conclusions: The correct identification of tasks and functions of the logistics leads to the recognition of its subject and tasks and correct identification of implications occurring among theory, practice and regulation. This knowledge is indispensable in the process of creation of projects of logistic services of each activity, both business and non-business one.
Theoretical Implications of IceCube Neutrinos
Ahlers, Markus
2014-03-01
The IceCube Collaboration has recently found evidence for an astrophysical flux of neutrinos. The flux is consistent with an isotropic and equal-flavor E-2 power-law spectrum from 60 TeV to 2 PeV. There are also indications that the neutrino spectrum beyond 2 PeV requires a spectral break or cutoff. The origin of the IceCube excess is not known, but its multi-messenger context can already provide some theoretical orientation. For instance, the production of PeV neutrinos require hadronic interactions of cosmic rays (CRs) with energies of a few 10 PeV, extending into the poorly understood transition region between Galactic and extra-Galactic CRs. A local contribution to the neutrino flux from Galactic accelerators is hence feasible and could show up as arrival direction clustering towards Galactic structures. In this context, a possible association of the PeV neutrino sources with unidentified TeV gamma-ray sources, peculiar supernovae or the Fermi Bubbles has been speculated. In addition, a local hadronic neutrino production would predict an observable PeV gamma-ray flux. Spectral features of the neutrino flux, in particular a break or cutoff, serve as additional hints for candidate CR sources and astrophysical environments for neutrino production. Possible scenearios include starburst galaxies, low-luminosity gamma-ray bursts and the cores of active galactic nuclei. I will outline general theoretical implications of the IceCube excess and summarize various source candidates.
Mathematical challenges from theoretical/computational chemistry
NONE
1995-12-31
The committee believes that this report has relevance and potentially valuable suggestions for a wide range of readers. Target audiences include: graduate departments in the mathematical and chemical sciences; federal and private agencies that fund research in the mathematical and chemical sciences; selected industrial and government research and development laboratories; developers of software and hardware for computational chemistry; and selected individual researchers. Chapter 2 of this report covers some history of computational chemistry for the nonspecialist, while Chapter 3 illustrates the fruits of some past successful cross-fertilization between mathematical scientists and computational/theoretical chemists. In Chapter 4 the committee has assembled a representative, but not exhaustive, survey of research opportunities. Most of these are descriptions of important open problems in computational/theoretical chemistry that could gain much from the efforts of innovative mathematical scientists, written so as to be accessible introductions to the nonspecialist. Chapter 5 is an assessment, necessarily subjective, of cultural differences that must be overcome if collaborative work is to be encouraged between the mathematical and the chemical communities. Finally, the report ends with a brief list of conclusions and recommendations that, if followed, could promote accelerated progress at this interface. Recognizing that bothersome language issues can inhibit prospects for collaborative research at the interface between distinctive disciplines, the committee has attempted throughout to maintain an accessible style, in part by using illustrative boxes, and has included at the end of the report a glossary of technical terms that may be familiar to only a subset of the target audiences listed above.
Abes, Elisa S.
2009-01-01
This article is an exploration of possibilities and methodological considerations for using multiple theoretical perspectives in research that challenges inequitable power structures in student development theory. Specifically, I explore methodological considerations when partnering queer theory and constructivism in research on lesbian identity…
Ecological Research Division Theoretical Ecology Program. [Contains abstracts
1990-10-01
This report presents the goals of the Theoretical Ecology Program and abstracts of research in progress. Abstracts cover both theoretical research that began as part of the terrestrial ecology core program and new projects funded by the theoretical program begun in 1988. Projects have been clustered into four major categories: Ecosystem dynamics; landscape/scaling dynamics; population dynamics; and experiment/sample design.
UNIFIED THEORETICAL MOMENT EXPRESSIONS FOR ELUTION CHROMATOGRAPHY AND FRONTAL CHROMATOGRAPHY
YANGGengliang; TAOZuyi
1992-01-01
The unified theoretical moment expressions for elution chromatography and frontal chromatography when the sorption process is described by a linear model were derived. The moment expressions derived by previous authors can be obtained from these unified theoretical moment expressions. In this paper, a mathematical analysis has been carried out so as to set up a unified theoretical basis for elution and frontal chromatography.
Eigen, D. J.; Davida, G. I.; Northouse, R. A.
1973-01-01
A criterion for characterizing an iteratively trained classifier is presented. The criterion is based on an information theoretic measure that is developed from modeling classifier training iterations as a set of cascaded channels. The criterion is formulated as a figure of merit and as a performance index to check the appropriateness of application of the characterized classifier to an unknown data base and for implementing classifier updates and data selection respectively.
Eigen, D. J.; Davida, G. I.; Northouse, R. A.
1974-01-01
A criterion for characterizing an iteratively trained classifier is presented. The criterion is based on an information theoretic measure that is developed from modeling classifier training iterations as a set of cascaded channels. The criterion is formulated as a figure of merit and as a performance index to check the appropriateness of application of the characterized classifier to an unknown data base and for implementing classifier updates and data selection, respectively.
The electronic states of TeH(+): a theoretical contribution.
Gonçalves dos Santos, Levi; de Oliveira-Filho, Antonio Gustavo S; Ornellas, Fernando R
2015-01-14
This work reports the first theoretical characterization of a manifold of electronic states of the as yet experimentally unknown monotellurium monohydride cation, TeH(+). Both Λ + S and Ω representations were described showing the twelve states correlating with the three lowest (Λ + S) dissociation channels, and the twenty five states associated with the five lowest Ω channels. The X (3)Σ(-) state is split into X1 0(+) and X2 1 separated by 1049 cm(-1); they are followed by the states a 2 (a (1)Δ) and b 0(+) (b (1)Σ(+)) higher in energy by 8554 and 17 383 cm(-1), respectively. These states can accommodate several vibrational energy levels. The potential energy curves of the Ω states arising from the bound A (3)Π, the weakly bound (1)Π, and the repulsive (5)Σ(-) states have a complex structure as shown by the very close avoided crossings just above ∼30 000 cm(-1). In particular, a double minima potential results for the state A1 2 that in principle could be probed experimentally through the A1 2-X2 1 system transitions. The states A2 1, b 0(+), and A4 0(+) offer possible routes to experimental investigations involving the ground state X1 0(+). Higher energy states are very dense and mostly repulsive. The high-level of the electronic structure calculations, by providing a global view of the electronic states and reliable spectroscopic parameters, is expected to further guide and motivate experimental studies on this species. Additional discussions on dipole and transition dipole moments, transition probabilities, radiative lifetimes, and a simulation of the single ionization spectrum complement the characterization of this system.
Three theoretical studies of ferroelectric materials in different geometries
Palova, Lucia
Using a combination of numerical and analytical techniques, I present characterizations of ferroelectric materials in bulk, thin-film and nanostructure geometries. My results have impact on ongoing research and on design for nanodevices. Size-dependent effects in ferroelectrics are important due to their long-range electrostatic interactions; thus their dielectric properties depend on electromechanical boundary conditions. In my first study, I address the effects of strain on the measured properties of thin-film (TF) ferroelectrics. It has been suggested that the observed suppression of many TF dielectric characteristics implies underlying strain gradients in the film. I show that the same effects can be explained by a simpler model with homogeneous strain, and I suggest a "smoking gun" benchtop probe. The quantum paraelectric-ferroelectric transition (QPFT) is the topic of my second study. Using methods including finite-size scaling and self-consistent Gaussian theory, I calculate the classical-quantum crossover in the dielectric susceptbility and the resulting temperature-pressure phase diagram; comparison with current experiment is excellent and predictions are made for future measurements. Here, temperature can be considered a "finite-size effet" in time, and previous results on the QPFT using diagrammatic techniques are recovered and extended using this approach. Recent synthesis of artificially structured oxides with "checkerboard" patterning at the nanoscale has been reported, and this serves as motivation for my third study. Here, I use first-principles methods to characterize an atomic-scale BiFeO3-BiMnO3 nanocheckerboard, and find that it has properties that are distinctive from those of either parent compound. More specifically, it has both a spontaneous polarization and magnetization, and also displays a magnetostructural effect. My work on this prototypical multiferroic nanocheckerboard motivates further theoretical and experimental studies of new
Theoretical studies of potential energy surfaces and computational methods
Shepard, R. [Argonne National Laboratory, IL (United States)
1993-12-01
This project involves the development, implementation, and application of theoretical methods for the calculation and characterization of potential energy surfaces involving molecular species that occur in hydrocarbon combustion. These potential energy surfaces require an accurate and balanced treatment of reactants, intermediates, and products. This difficult challenge is met with general multiconfiguration self-consistent-field (MCSCF) and multireference single- and double-excitation configuration interaction (MRSDCI) methods. In contrast to the more common single-reference electronic structure methods, this approach is capable of describing accurately molecular systems that are highly distorted away from their equilibrium geometries, including reactant, fragment, and transition-state geometries, and of describing regions of the potential surface that are associated with electronic wave functions of widely varying nature. The MCSCF reference wave functions are designed to be sufficiently flexible to describe qualitatively the changes in the electronic structure over the broad range of geometries of interest. The necessary mixing of ionic, covalent, and Rydberg contributions, along with the appropriate treatment of the different electron-spin components (e.g. closed shell, high-spin open-shell, low-spin open shell, radical, diradical, etc.) of the wave functions, are treated correctly at this level. Further treatment of electron correlation effects is included using large scale multireference CI wave functions, particularly including the single and double excitations relative to the MCSCF reference space. This leads to the most flexible and accurate large-scale MRSDCI wave functions that have been used to date in global PES studies.
Solvothermal synthesis and theoretical study of a polypyridium trimesylate adduct
Yulan Zhu; Feng Ma; Kuirong Ma; Li Cao; Lianhua Zhao
2011-09-01
The title compound (C9H3O6·C20H17N4)4·0.5H2O 1 was isolated from solvothermal synthesis of 4'-(4-pyridyl)-2,2':6',2'-terpyridine (pytpy) and trimesic acid (1,3,5-benzenetricarboxylic acid, H3BTC). It was characterized by element analysis, IR, TGA, XRD, X-ray single-crystal diffraction, and spectroscopy properties, together with quantum chemistry calculation of spectrum (UV-vis spectra) through the method b3lyp/6-31 t g (d,p) are also investigated. Single-crystal X-ray diffraction shows 1 possesses a 3-D supramolecular network with 1-D six-fold helical double chains built from protonated (H3pytpy)$^{3+}_{n}$ cations and deprotonated (BTC)$^{3−}_{n}$ anions. The maximum of the fluorescent emission bands of 1 is located at 427 nm (ex = 266 nm), with a shoulder at about 390 nm. The result of theoretic calculations confirms that 1 has small HOMO-LUMO energy gap (1.24 eV) and high chemical reactivity.
Oxidative dissolution of silver nanoparticles: A new theoretical approach.
Adamczyk, Zbigniew; Oćwieja, Magdalena; Mrowiec, Halina; Walas, Stanisław; Lupa, Dawid
2016-05-01
A general model of an oxidative dissolution of silver particle suspensions was developed that rigorously considers the bulk and surface solute transport. A two-step surface reaction scheme was proposed that comprises the formation of the silver oxide phase by direct oxidation and the acidic dissolution of this phase leading to silver ion release. By considering this, a complete set of equations is formulated describing oxygen and silver ion transport to and from particles' surfaces. These equations are solved in some limiting cases of nanoparticle dissolution in dilute suspensions. The obtained kinetic equations were used for the interpretation of experimental data pertinent to the dissolution kinetics of citrate-stabilized silver nanoparticles. In these kinetic measurements the role of pH and bulk suspension concentration was quantitatively evaluated by using the atomic absorption spectrometry (AAS). It was shown that the theoretical model adequately reflects the main features of the experimental results, especially the significant increase in the dissolution rate for lower pH. Also the presence of two kinetic regimes was quantitatively explained in terms of the decrease in the coverage of the fast dissolving oxide layer. The overall silver dissolution rate constants characterizing these two regimes were determined.
Steinberg, Idan; Hershkovich, Hadas Sara; Gannot, Israel; Eyal, Avishay
2014-03-01
Osteoporosis is a widespread disorder, which has a catastrophic impact on patients lives and overwhelming related to healthcare costs. Recently, we proposed a multispectral photoacoustic technique for early detection of osteoporosis. Such technique has great advantages over pure ultrasonic or optical methods as it allows the deduction of both bone functionality from the bone absorption spectrum and bone resistance to fracture from the characteristics of the ultrasound propagation. We demonstrated the propagation of multiple acoustic modes in animal bones in-vitro. To further investigate the effects of multiple wavelength excitations and of induced osteoporosis on the PA signal a multispectral photoacoustic system is presented. The experimental investigation is based on measuring the interference of multiple acoustic modes. The performance of the system is evaluated and a simple two mode theoretical model is fitted to the measured phase signals. The results show that such PA technique is accurate and repeatable. Then a multiple wavelength excitation is tested. It is shown that the PA response due to different excitation wavelengths revels that absorption by the different bone constitutes has a profound effect on the mode generation. The PA response is measured in single wavelength before and after induced osteoporosis. Results show that induced osteoporosis alters the measured amplitude and phase in a consistent manner which allows the detection of the onset of osteoporosis. These results suggest that a complete characterization of the bone over a region of both acoustic and optical frequencies might be used as a powerful tool for in-vivo bone evaluation.
Towards a theoretical foundation for morphological computation with compliant bodies.
Hauser, Helmut; Ijspeert, Auke J; Füchslin, Rudolf M; Pfeifer, Rolf; Maass, Wolfgang
2011-12-01
The control of compliant robots is, due to their often nonlinear and complex dynamics, inherently difficult.The vision of morphological computation proposes to view these aspects not only as problems, but rather also as parts of the solution. Non-rigid body parts are not seen anymore as imperfect realizations of rigid body parts, but rather as potential computational resources. The applicability of this vision has already been demonstrated for a variety of complex robot control problems. Nevertheless, a theoretical basis for understanding the capabilities and limitations of morphological computation has been missing so far. We present a model for morphological computation with compliant bodies, where a precise mathematical characterization oft he potential computational contribution of a complex physical body is feasible. The theory suggests that complexity and nonlinearity, typically unwanted properties of robots, are desired features in order to provide computational power. We demonstrate that simple generic models of physical bodies,based on mass-spring systems, can be used to implement complex nonlinear operators. By adding a simple readout(which is static and linear) to the morphology, such devices are able to emulate complex mappings of input to output streams in continuous time. Hence, by outsourcing parts of the computation to the physical body, the difficult problem of learning to control a complex body, could be reduced to a simple and perspicuous learning task, which can not get stuck in local minima of an error function.
Theoretical and clinical overview of affective temperaments in mood disorders
Xenia Gonda
2015-07-01
Full Text Available Temperaments are imperturbable variations of personality, traits and ways of reacting to the environment that characterize individuals and remain constant throughout several different situations. Temperaments usually play a central role in determining emotional reactions, therefore several temperamental models have attempted to establish the potential relationship between temperaments and affective disorders. According to Hagop Akiskal, affective temperaments are subclinical and subaffective trait-like manifestations of affective disorders. Unlike several models of temperament which were exclusively developed theoretically in order to describe healthy human functioning, later extrapolated to capture the pathological domains of mental and behavioral features, the current model of affective temperaments was developed on classical traditions and mainly based on the observation of subjects with mood disorders and their healthy first degree relatives. There is accumulating evidence concerning the development of affective temperaments based on their adaptive evolutionary characteristics and genetic background, and normative data from large national studies on general and healthy samples indicate their universal characteristics. Studies in affective patient populations indicate that the relationship between affective temperaments and affective illness is more complex than a simple extrapolation from psychopathology and mental health, and affective temperaments may represent a latent state of the staging model, playing a pathoplastic role in mood disorders determining their evolution, clinical features, main characteristics and outcome. A large body of data on affective temperaments has been published during the last decade, deserving a critical analysis presented in this overview.
Development of a theoretical-practical script for clinical simulation
Renata Paula Fabri
Full Text Available Abstract OBJECTIVE To develop a theoretical-practical script based on the opinion of experts to be used in simulated clinical activities. METHOD Qualitative study through analysis of content of interviews with experts on the theme in order to develop the proposed script. Of the 24 invited experts, 12 specialists from educational institutions in Brazil and abroad participated in the study in compliance with the ethical precepts. The experts responded to questions on the characterization of their study attributes and described the items required for the development of a simulated scenario. In view of the responses obtained, data content was analyzed and classified into units and subunits of significance. RESULTS The items mentioned for the development of the script generated seven units of significance. The units and subunits of significance were gathered in three stages of the main components of the simulated scenario: prior, preparation, and finals. CONCLUSION This study enables an innovative, stimulating teaching experience, making it easier for professors to use the simulation resource as a learning process in an effective and objective manner, as a guide to professors and researchers in the area of clinical simulation.
Theoretical study of rock mass investigation efficiency
Holmen, Johan G.; Outters, Nils [Golder Associates, Uppsala (Sweden)
2002-05-01
The study concerns a mathematical modelling of a fractured rock mass and its investigations by use of theoretical boreholes and rock surfaces, with the purpose of analysing the efficiency (precision) of such investigations and determine the amount of investigations necessary to obtain reliable estimations of the structural-geological parameters of the studied rock mass. The study is not about estimating suitable sample sizes to be used in site investigations.The purpose of the study is to analyse the amount of information necessary for deriving estimates of the geological parameters studied, within defined confidence intervals and confidence level In other words, how the confidence in models of the rock mass (considering a selected number of parameters) will change with amount of information collected form boreholes and surfaces. The study is limited to a selected number of geometrical structural-geological parameters: Fracture orientation: mean direction and dispersion (Fisher Kappa and SRI). Different measures of fracture density (P10, P21 and P32). Fracture trace-length and strike distributions as seen on horizontal windows. A numerical Discrete Fracture Network (DFN) was used for representation of a fractured rock mass. The DFN-model was primarily based on the properties of an actual fracture network investigated at the Aespoe Hard Rock Laboratory. The rock mass studied (DFN-model) contained three different fracture sets with different orientations and fracture densities. The rock unit studied was statistically homogeneous. The study includes a limited sensitivity analysis of the properties of the DFN-model. The study is a theoretical and computer-based comparison between samples of fracture properties of a theoretical rock unit and the known true properties of the same unit. The samples are derived from numerically generated boreholes and surfaces that intersect the DFN-network. Two different boreholes are analysed; a vertical borehole and a borehole that is
Theoretical and Experimental Spectroscopic Analysis of Cyano-Substituted Styrylpyridine Compounds
Jorge Lopez-Cruz
2013-02-01
Full Text Available A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyrylpyridine, trans-2-[3-methyl-(m-cyanostyryl]pyridine and trans-4-(m-cyanostyrylpyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT in both gas and solution phases. For theoretical UV-Vis and 1H NMR spectra, the Time-Dependent DFT (TD-DFT and the Gauge-Including Atomic Orbital (GIAO methods were used, respectively. The theoretical characterization matched the experimental measurements, showing a good correlation. The effect of cyano- and methyl- substituents, as well as of the N-atom position in the pyridine ring on the UV-Vis, IR and NMR spectra, was evaluated. The UV-Vis results showed no significant effect due to electron-withdrawing cyano- and electron-donating methyl-substituents. The N-atom position, however, caused a slight change in the maximum absorption wavelengths. The IR normal modes were assigned for the cyano- and methyl-groups. 1H NMR spectra showed the typical doublet signals due to protons in the trans position of a double bond. The theoretical characterization was visibly useful to assign accurately the signals in IR and 1H NMR spectra, as well as to identify the most probable conformation that could be present in the formation of the styrylpyridine-like compounds.
Theoretical and experimental spectroscopic analysis of cyano-substituted styrylpyridine compounds.
Castro, Maria Eugenia; Percino, Maria Judith; Chapela, Victor M; Ceron, Margarita; Soriano-Moro, Guillermo; Lopez-Cruz, Jorge; Melendez, Francisco J
2013-02-18
A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)]pyridine and trans-4-(m-cyanostyryl)pyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT) in both gas and solution phases. For theoretical UV-Vis and 1H NMR spectra, the Time-Dependent DFT (TD-DFT) and the Gauge-Including Atomic Orbital (GIAO) methods were used, respectively. The theoretical characterization matched the experimental measurements, showing a good correlation. The effect of cyano- and methyl- substituents, as well as of the N-atom position in the pyridine ring on the UV-Vis, IR and NMR spectra, was evaluated. The UV-Vis results showed no significant effect due to electron-withdrawing cyano- and electron-donating methyl-substituents. The N-atom position, however, caused a slight change in the maximum absorption wavelengths. The IR normal modes were assigned for the cyano- and methyl-groups. 1H NMR spectra showed the typical doublet signals due to protons in the trans position of a double bond. The theoretical characterization was visibly useful to assign accurately the signals in IR and 1H NMR spectra, as well as to identify the most probable conformation that could be present in the formation of the styrylpyridine-like compounds.