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91.
将Gly-GlyO、4,4'-联吡啶与Cu(NO_3)_2·H_2O在二次水溶液中反应,合成出以4,4'-bpy为中继基、Cly-GlyO为螯环的新型双核铜配合物,经X射线单晶结构分析确定该配合物晶体的化学结构式为[(H_2NCH_2CONHCH_2COO)Cu(OH)(C_(10)H_8N_2)Cu(ON)(H_2NCH_2CONHCH_2COO)]·9H_2O.晶体属P 空间群,晶胞参数a=1.1412nm,b=1.2298nm,c=1.4269nm,α=113.82°,β=101.91°,γ=103.64°,Z=2.最终一致性因子R值为0.068,R_w值为0.057,标准偏差σ=0.1951。 相似文献
92.
Timothy J. Garrett Maria C. Prieto-Conaway Viatcheslav Kovtoun Huy Bui Nick Izgarian George Stafford Richard A. Yost 《International journal of mass spectrometry》2007,260(2-3):166
We describe a new intermediate-pressure MALDI linear ion trap mass spectrometer and its capabilities for imaging mass spectrometry. The instrument design is described and is characterized in terms of four performance issues (1) MALDI performance at intermediate pressure; (2) analysis of samples on non-conductive and conductive glass slides; (3) critical importance of tandem mass spectrometry (both MS2 and MS3) for identification of analyte species and imaging of isobaric species; (4) capability for repeated analysis of the same tissue section. Application of the new instrument to imaging phospholipids in rat brain sections is described in detail. 相似文献
93.
Weixin Lin 《Journal of Molecular Structure》2003,655(1):37-45
In this work, two series of ethylene-dimethylaminoethylmethacrylate (EDAM) and ethylene-methyl acrylate copolymers (EMA) with different comonomer content were studied by high-resolution solid-state 13C NMR spectroscopy. Biexponential 13C spin-lattice relaxation behaviors of the crystalline region were observed for all copolymer samples either melt-quenched or isothermally crystallized. The relative content of the shorter 13C T1 component to that of the longer 13C T1 component was found to increase with comonomer content. By employing a new pulse sequence which can be considered as a combination of Goldman-Shen's and Torchia's pulse sequences, it was demonstrated that the shorter 13C T1 component is corresponding to the intermediate part of the crystalline region. The thickness of the intermediate part is estimated to be about 0.85 nm. 相似文献
94.
95.
Catechins are strong autoxidant to produce steady intermediate in alkali solution. In present work, we, for the first time, developed a electrochemical method based on ruthenium tris (2, 2′) bipyridyl (Ru(bpy)33+) modified boron-doped diamond (BDD) electrode to investigate the electrochemical reduction of catechin autoxidation intermediate with its existence verified by the electron spin resonance (ESR). The reduction peak potential was observed at −855.5 mV, not appearing either in acid solution (pH 2) containing catechins or in oxidized catechin solution (pH 12). Moreover, the effects of pH, ascorbic acid, Cu2+, Fe2+ and autoxidation time are investigated, demonstrating the reduction peak being really the reduction of catechin autoxidation intermediate. It is found that the peak current is proportional to scan rate, indicative of a surface confined reduction process. Sensitive amperometric response was obtained covering linear range from 0.3268 μM to 0.1591 mM. The determination of catechin in commercial preparations using this method shows satisfactory results comparable with those of the traditional methods. 相似文献
96.
Rosalie Iemhoff 《Annals of Pure and Applied Logic》2019,170(11):102711
This paper presents a uniform and modular method to prove uniform interpolation for several intermediate and intuitionistic modal logics. The proof-theoretic method uses sequent calculi that are extensions of the terminating sequent calculus for intuitionistic propositional logic. It is shown that whenever the rules in a calculus satisfy certain structural properties, the corresponding logic has uniform interpolation. It follows that the intuitionistic versions of and (without the diamond operator) have uniform interpolation. It also follows that no intermediate or intuitionistic modal logic without uniform interpolation has a sequent calculus satisfying those structural properties, thereby establishing that except for the seven intermediate logics that have uniform interpolation, no intermediate logic has such a sequent calculus. 相似文献
97.
Klaus Peter Jungmann 《Hyperfine Interactions》2006,171(1-3):41-55
State of the art laser technology and modern spectroscopic methods allow to address issues of fundamental symmetries and fundamental
interactions in atoms with high precision experiments. In particular the discrete symmetries Parity (P), Charge Conjugation
(C), Time Reversal (T) as well as their combinations CP and CPT are in the center of interest at present. Actual projects
are concerned with Parity Violation in atoms, Time Reversal Violation in β-decays and searches for permanent Electric Dipole Moments (EDMs), and tests of CPT conservation in particle-antiparticle
properties, in particular antiprotonic atoms.
This work is supported in part by the Dutch Stichting voor Fundamenteel Onderzoek der Materie (FOM) under programme number
48 (TRIμP). 相似文献
98.
Intermediate-temperature polymer-electrolyte fuel cells (IT-PEFCs), operated at an elevated temperature of ≈120 °C, would enable simplified system design and a potential increase in fuel cell performance compared to state-of-the-art low-temperature (LT-)PEFCs. As LT-PEFC membranes rely on the presence of water and high-temperature (HT-)PEFCs suffer from sluggish oxygen reduction reaction (ORR) kinetics, alternative materials must be developed. Promising candidates are protic ionic liquids (PILs) immobilized in, e.g., a host polymer. PILs’ properties, such as weak ion adsorption, high acidity of the proton-carrying ion, an excess of the anion precursor, and a high oxygen diffusivity and solubility, are favorable for achieving high ORR rates. Concepts proposed in the literature for incorporating PILs into MEA components are presented herein, and their utility for future IT-PEFCs is discussed. 相似文献
99.
We present a formulation of deformed oscillator algebra which leads to intermediate statistics as a continuous interpolation between Bose-Einstein and Fermi-Dirac statistics. It is deduced that a generalized permutation or exchange symmetry leads to the introduction of the basic number and it is then established that this in turn leads to the deformed algebra of oscillators. We obtain the mean occupation number describing the particles obeying intermediate statistics which thus establishes the interpolating statistics and describe boson-like and fermion-like particles obeying intermediate statistics. We also obtain an expression for the mean occupation number in terms of an infinite continued fraction, thus clarifying successive approximations. 相似文献
100.
介绍了中高能电子散射全截面绝对测量装置的设计,采用直线透射技术.因采用了恒温控制作用室,以便较准确测量反应室的绝对气压值;同时采用静电型圆柱能量分析器,并用计数率测量模式代替通常的束流强度测量模式,从而可以大幅度减小接收立体角,抑制零度角的弹性散射贡献.通过以上几项措施,可以有效地提高测量的精度,从而可以对一些有意义的分子的中、高能电子散射全截面进行绝对测量. 相似文献