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Related Properties (relate + property)
Selected AbstractsThe N -Acylated Derivatives of Parent Complex [{(,-SCH2)2NH}Fe2(CO)6] as Active Site Models of Fe-Only Hydrogenases: Synthesis, Characterization, and Related PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2008Li-Cheng Song Abstract A series of N -acylated diiron azadithiolate complexes as H-cluster models was synthesized and structurally characterized. Treatment of parent complex [{(,-SCH2)2NH}Fe2(CO)6] (A) with 2-chloroacetic acid in the presence of dicyclohexylcarbodiimide or with 2-chloroacetyl chloride in the presence of Et3N gave N -chloroacetyl complex [{(,-SCH2)2NC(O)CH2Cl}Fe2(CO)6] (1). Further treatment of 1 with MeC(O)SK afforded N -acetylthioacetyl complex [{(,-SCH2)2NC(O)CH2SC(O)Me}Fe2(CO)6] (2). N -Ethoxylcarbonylacetyl complex [{(,-SCH2)2NC(O)CH2CO2Et}Fe2(CO)6] (3) and N-heterocyclic complexes [{(,-SCH2)2NC(O)C4H3Y-2}Fe2(CO)6] (4, Y = O; 5, Y = S) were produced by reactions of A with EtO2CCH2C(O)Cl, 2-furancarbonyl chloride, and 2-thiophenecarbonyl chloride in the presence of pyridine or Et3N. Similarly, N -malonyl complex [{Fe2(CO)6(,-SCH2)2NC(O)}2CH2] (6) and N -carbonylbenzaldehyde complex [{(,-SCH2)2NC(O)C6H4CHO- p}Fe2(CO)6] (7) could be obtained by reaction of A with malonyl dichloride in the presence of pyridine and with p -CHOC6H4C(O)Cl in the presence of Et3N. More interestingly, further reaction of 7 with PhCHO and pyrrole in a 1:3:4 molar ratio in the presence of BF3·OEt2 followed by p -chloranil yielded the first light-driven type of model complex containing an N -carbonylphenylporphyrin moiety [{(,-SCH2)2NC(O)(TPP)}Fe2(CO)6] (8, TPP = tetraphenylporphyrin group). Whereas the molecular structures of 2, 5, and 7 were established by X-ray crystallography, the electrochemical properties of 2,5 as well as the proton reduction to hydrogen gas catalyzed by 2 and 3 were studied by CV techniques.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Studies on 4,7-di-substitution effects of one ligand in [Ru(Phen)3]2 with DFT methodJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 4 2002Kangcheng Zheng Abstract Studies on the complex [Ru(phen)3]2+ (phen = 1,10-phenanthroline) and its derivatives with 4,7-di-substitution on one ligand(phen) were carried out using the DFT method at the B3LYP/LanL2DZ level of theory. The trends in the substituent effects caused by the electron-pushing group (OH) and the electron-withdrawing group (F), on the electronic structures and the related properties, for example, the energies and the components of some frontier molecular orbitals, the spectroscopy properties, and the net charge populations of some main atoms of the complexes, etc., have been investigated. The computational results show that the substituents have some interesting effects on the electronic structures and the related properties of the complexes. First, according to the analysis of components of LUMO of the complexes, the electron-withdrawing group (F) can activate the main ligand (the substituted ligand, i.e., 2R-phen) and passivate the coligands, on the contrary, the electron-pushing group (OH) can activate the coligands and passivate the main ligand in the first electronic excited states of complexes. Second, both the electron-pushing group (OH) and the electron-withdrawing group (F) can cause a red shift in the electronic ground bands. Third, the characteristics of the atomic net charge populations on the main ligand can also be analyzed in detail by means of a schematic map expressed by several series of arrowheads based on the law of polarity alternation and the idea of polarity interference. The most negative charges are populated on N1, the next most net negative charges are populated on C3 among the skeleton atoms for the three complexes, etc. The computational results can be better used to explain some experimental phenomena and trends. © 2002 Wiley Periodicals, Inc. J Comput Chem 4: 436,443, 2002; DOI 10.1002/jcc.10038 [source] Solvatochromism of carbenium,arene EDA (electrondonor,acceptor) complexes and their behaviour on silicaJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 2001Stefan Spange Abstract Spectral characteristics of two different types of electron donor,acceptor (EDA) complexes with charged components (arene,carbenium and anion,, acceptor) are presented. The UV,Vis absorption maxima of the charge-transfer (CT) band (,max,CT) of the EDA complexes were measured in various solvents and after adsorption on silica. Tropylium, triarylmethylium and diarylmethylium ions in combination with aromatic , donors, e.g. pyrene, acenaphthene and methoxy-substituted benzene derivatives and also the tetraethylammonium iodide,1,3,5-trinitrobenzene complex have been investigated by means of a special UV,Vis technique in transparent slurries of silica nanoparticles in 1,2-dichloroethane. Multiple linear regression analyses of the ,max,CT values of the EDA complexes in various solvents and on silica with the Kamlet,Taft solvent parameters and structure,reactivity terms of the complex components, e.g. the oxidation potential of the arene component or the Hammett substituent constant, ,p+, of the arylmethyl component, show their related properties to the solution complexes. The influence of the electron-pair donating capacity of a solvent on ,max,CT of carbenium/arene complexes was compared with the property of the silica surface in order to link EDA complexes. For the diarylmethyl carbenium ion,pyrene complexes on silica, the presence of a ,-like structure is discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source] A CONCEPTUAL UNDERSTANDING OF REQUIREMENTS FOR THEORY-BUILDING RESEARCH: GUIDELINES FOR SCIENTIFIC THEORY BUILDING,JOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 3 2008JOHN G. WACKER Business academics have focused their attention on empirical investigation of programs' effect on organizational competitive performance. These studies primarily emphasize theory building. With the many definitions of theory, academics are not certain whether their research papers meet the specific requirements for theory development required by the academic field of the philosophy of science. Certainly, supply chain academics generally believe that their academic articles fulfill the requirements of theory building. Although many of these articles do have elements of theory, more focus is needed on the specific requirements of theory to assure that academic research is "good" theory building. The primary purpose of this research paper is to logically develop a set of guidelines to assist empirical researchers to assure that their studies fulfill the requirements of good theory based upon traditional scientific theory building. By fulfilling the requirements of good theory, researchers will develop studies that will have a lasting impact on their academic field. To achieve a lasting impact on an academic field, it is necessary to follow a logical plan. This article provides a plan for logical guidelines for developing an understanding of how and why "good" theory building is achieved. This article logically develops a formal conceptual definition of theory along with its related properties to understand these guidelines. Next, it analyzes the requirements of theory, "good" theory, and their properties. These guidelines are included in the existing philosophy of science publications. However, this article consolidates these sources and logically explains why these guidelines are needed. In the conclusion, the guidelines are summarized to serve as a summary checklist for supply chain researchers to use for ensuring their articles will be recognized as a contribution to the academic field. So in that sense, this article does not develop a revolutionary new insight into theory-building empirical articles, but rather integrates diverse traditional philosophy of science requirements into a much simpler set of guidelines. Through logical development of these guidelines, researchers will understand the structure of theory and how to ensure their studies can be modified to have a lasting impact on the field of supply chain management. [source] On (,, , , q)-fuzzy filters of R0 -algebrasMLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 5 2009Xueling Ma Abstract In this paper, we introduce the notions of (,, , , q)-fuzzy filters and (,, , , q)-fuzzy Boolean (implicative) filters in R0 -algebras and investigate some of their related properties. Some characterization theorems of these generalized fuzzy filters are derived. In particular, we prove that a fuzzy set in R0 -algebras is an (,, , , q)-fuzzy Boolean filter if and only if it is an (,, , , q)-fuzzy implicative filter. Finally, we consider the concepts of implication-based fuzzy Boolean (implicative) filters of R0 -algebras (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Consequences of neocompact quantifier eliminationMLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 2 2003Stefano Baratella Abstract We provide some consequences of a Quantifier Elimination Property and related properties previously introduced (see [4]) in the setting of Banach space structures. We further consider some applications of quantifierfree definability, such as strict convexity via the definability of certain mapping and the continuity of definable functions. [source] On some properties of suboptimal colorings of graphsNETWORKS: AN INTERNATIONAL JOURNAL, Issue 2 2004Ivo Blöchliger Abstract Starting from the trivial observation that, in any optimal coloring of a graph, there always exists a node v such that its neighborhood N(v) contains all colors, we examine related properties in suboptimal colorings (i.e., those using more than ,(G) colors, where ,(G) is the chromatic number). In particular, we show that, in any (,(G) + p)-coloring of G, there is a node v such that its generalized neighborhood Nq(v) with q = max{2p , 1, 2} contains ,(G) colors for p , 1. Additional properties of (,(G) + p)-colorings are also given. © 2004 Wiley Periodicals, Inc. [source] Copolymers based on poly(butylene terephthalate) and polycaprolactone- block -polydimethylsiloxane- block -polycaprolactonePOLYMER INTERNATIONAL, Issue 6 2010Vesna V Anti Abstract A series of novel thermoplastic elastomers, based on poly(butylene terephthalate) (PBT) and polycaprolactone- block -polydimethylsiloxane- block -polycaprolactone (PCL-PDMS-PCL), with various mass fractions, were synthesized through melt polycondensation. In the synthesis of the poly(ester-siloxane)s, the PCL blocks served as a compatibilizer for the non-polar PDMS blocks and the polar comonomers dimethyl terephthalate and 1,4-butanediol. The introduction of PCL-PDMS-PCL soft segments resulted in an improvement of the miscibility of the reaction mixture and therefore in higher molecular weight polymers. The content of hard PBT segments in the polymer chains was varied from 10 to 80 mass%. The degree of crystallinity of the poly(ester-siloxane)s was determined using differential scanning calorimetry and wide-angle X-ray scattering. The introduction of PCL-PDMS-PCL soft segments into the polymer main chains reduced the crystallinity of the hard segments and altered related properties such as melting temperature and storage modulus, and also modified the surface properties. The thermal stability of the poly(ester-siloxane)s was higher than that of the PBT homopolymer. The inclusion of the siloxane prepolymer with terminal PCL into the macromolecular chains increased the molecular weight of the copolymers, the homogeneity of the samples in terms of composition and structure and the thermal stability. It also resulted in mechanical properties which could be tailored. Copyright © 2010 Society of Chemical Industry [source] Comparison of device performance and measured transport parameters in widely-varying Cu(In,Ga) (Se,S) solar cellsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 1 2006I. L. Repins Abstract We report the results of an extensive study employing numerous methods to characterize carrier transport within copper indium gallium sulfoselenide (CIGSS) photovoltaic devices, whose absorber layers were fabricated by diverse process methods in multiple laboratories. This collection of samples exhibits a wide variation of morphologies, compositions, and solar power conversion efficiencies. An extensive characterization of transport properties is reported here,including those derived from capacitance,voltage, admittance spectroscopy, deep level transient spectroscopy, time-resolved photoluminescence, Auger emission profiling, Hall effect, and drive level capacitance profiling. Data from each technique were examined for correlation with device performance, and those providing indicators of related properties were compared to determine which techniques and interpretations provide credible values for transport properties. Although these transport properties are not sufficient to predict all aspects of current-voltage characteristics, we have identified specific physical and transport characterization methods that can be combined using a model-based analysis algorithm to provide a quantitative prediction of voltage loss within the absorber. The approach has potential as a tool to optimize and understand device performance irrespective of the specific process used to fabricate the CIGSS absorber layer. Copyright © 2005 John Wiley & Sons, Ltd. [source] Tests for an Epidemic Change in a Sequence of Exponentially Distributed Random VariablesBIOMETRICAL JOURNAL, Issue 8 2003Asoka Ramanayake Abstract Consider a sequence of independent exponential random variables that is susceptible to a change in the means. We would like to test whether the means have been subjected to an epidemic change after an unknown point, for an unknown duration in the sequence. The likelihood ratio statistic and a likelihood ratio type statistic are derived. The distribution theories and related properties of the test statistics are discussed. Percentage points and powers of the tests are tabulated for selected values of the parameters. The powers of these two tests are then compared to the two statistics proposed by Aly and Bouzar. The tests are applied to find epidemic changes in the set of Stanford heart transplant data and air traffic arrival data. [source] | |||||||||||||