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81.
XIE Hai-ming YAN Xue-dong YU Hai-ying ZHANG Ling-yun YANG Gui-ling XU Yang WANG Rong-shun **. Department of Chemistry Northeast Normal University Changchun P. R. China . Department of Chemistry Inner Mongolia University for Nationalities Tongliao P. R. China 《高等学校化学研究》2006,22(5):639-642
IntroductionLithium ion batteries have attracted a great interestbecause of their commercial applications in portable de-vices[1,2].Great efforts have been made to improve theenergy density of new anode materials.For example,Sn-based compounds,such as SnO… 相似文献
82.
MAARTEN J. PUNT HANS‐PETER WEIKARD ROLF A. GROENEVELD EKKO C. VAN IERLAND JAN H. STEL 《Natural Resource Modeling》2010,23(4):610-646
Abstract The EU Marine Strategy Directive (MSD) has a regional focus in its implementation. The directive obliges countries to take multiple uses and the marine strategies of neighboring countries into account when formulating marine strategies and when designating marine protected areas (MPAs). We use game theoretical analysis both to find the optimal size of MPAs with multiple uses by multiple countries and to investigate the influences of multiple uses on cooperation. To this end, we develop a model in which two specific uses, fisheries and nature conservation, by multiple countries are considered in a strategic framework. The results of the paper suggest that EU marine policy such as the MSD and the coming Maritime Policy may help to secure the highest possible benefits from these MPAs if these policies induce cooperation among countries, but only if policies force countries to consider all possible benefits of MPAs. In fact cooperation on a single issue may give a worse outcome than the noncooperative equilibrium. The results also indicate that cooperation may be hard to achieve because of defector incentives, and therefore policy measures should be strict in enforcing cooperation on all possible uses of MPAs. 相似文献
83.
A new Ni(II) coordination polymer [Ni(L)2(SCN)2]n(L = 1,4-bis(benzimidazol-1-yl)butane) was synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group C2/c with a = 9.4760(3), b = 24.0408(8), c = 16.5871(5) A, β = 99.832(3)°, V = 3723.2(2) A3, Z = 4, Dc = 1.348 g/cm3, F(000) = 1576, the final R = 0.0486 and w R = 0.0936 for 2938 observed reflections with I 2σ(I) for the complex. Structural analysis shows that the coordination polymer possesses a 2D(4,4) layer structure which is composed of Ni(II) centers bridged by L ligand with two kinds of conformations and further assembled into a 3D supramolecular network via π-π stacking interactions. In addition, the fluorescence and catalytic properties, for the degradation of Congo red, of the complex were investigated. 相似文献
84.
Antonie J. W. G. Visser Kees Vos Jillert S. Santema Jan Bouwstra Arie VAN Hoek 《Photochemistry and photobiology》1987,46(4):457-466
Spectral and time-resolved fluorescence studies have been carried out on N(3)-undecyllumi-flavin dispersed in reversed micelles composed of the surfactant sodium di(2-ethylhexyl) sulfosuccinate (Aerosol OT, AOT), various amounts of water and n -heptane as continuous phase. The fluorescence spectral properties (spectral distribution, quantum efficiencies and lifetimes) as function of the water to AOT molar ratio suggest that the flavin occupies a position within the surfactant boundary layer in close contact with water. The fluorescence anisotropy exhibits biexponential decay with a short (0.3 ns) and a longer (1.6–2.4 ns) correlation time. The contribution of the short component increases with the growth of the droplet providing evidence for enhanced flexibility of the flavin in the interfacial layer. 相似文献
85.
ANALYSIS AND IMPROVEMENT OF PERTURBATION SERIES 总被引:1,自引:0,他引:1
86.
Analytical chemistry does play a key role in the chemical characterization of the environment and it appears that X-ray spectrometry,
in its many forms, is one of the most relevant analytical techniques in preventive conservation, as it is in cultural heritage
research in general. X-ray spectrometry has indeed been the method of choice for the characterization of the inorganic composition
of atmospheric aerosols, for a long time. 相似文献
87.
MARCEL VAN ASSEN CHRIS SNIJDERS JEROEN WEESIE 《The Journal of mathematical sociology》2013,37(2):159-180
A fuzzy set theoretical framework is proposed for the analysis of sociometric structure characterized by vagueness of liking between individuals and a person's relative degree of belonging to a social group. Max‐min transitivity of a fuzzy relation is employed as a basic concept to examine the degree of liking and clustering in group structures. A distance model based on min‐max transitivity is also formulated as a special case of transitivity analysis. Other notions of transitivity such as the max‐product and the max‐* are also discussed. An empirical analysis is performed to examine the applicability of the proposed transitivity concepts. It appears that the current methodological construct provides a more appropriate perspective in the analysis of the group structure properties. 相似文献
88.
Existing methods for predicting resource divisions in laboratory exchange networks do not take into account the sequential nature of the experimental setting. We extend network exchange theory by considering sequential exchange. We prove that Sequential Power-Dependence Theory—unlike Power-Dependence Theory and most other exchange theories—has a unique point prediction for resource divisions in every network, and we show that these point predictions fare well in comparison to those from established theories. 相似文献
89.
MANASH KUMAR PAUL A LYSSOIVAN R KOCH G VAN WASSENHOVE M VERVIER G BERTSCHINGER R LAENGNER B UNTERBERG G SERGIENKO V PHILIPPS T WAUTERS 《Pramana》2013,80(1):121-131
Ion cyclotron wall conditioning (ICWC) discharges, in pulsed-mode operation, were carried out in the limiter tokamak TEXTOR to explore safe operational regimes for the experimental parameters for possible ICWC-discharge cleaning in International Thermonuclear Experimental Reactor (ITER) at half field. Antenna coupling properties obtained during the ion cyclotron range of frequencies (ICRF) wall conditioning experiments performed in helium–hydrogen mixture in TEXTOR were analysed in relation to the obtained ICWC-plasma characterization results. Satisfactory antenna coupling in the mode conversion scenario along with reproducible generation of ICRF plasmas for wall conditioning, were achieved by coupling radio frequency (RF) power from one or two ICRF antennas. The plasma breakdown results obtained in the TEXTOR tokamak have been compared with the predictions of a zero-dimensional RF plasma production model. The present study of ICWC emphasizes the beneficial effect of application of an additional (along with toroidal magnetic field) stationary vertical (B V???B T) or oscillating poloidal magnetic field (B P???B T) on antenna coupling and relevant plasma parameters. 相似文献
90.
Rotational spectra of the Kr-H2O van der Waals complex were measured in the frequency range 4–19 GHz using a pulsed jet cavity Fourier transform microwave spectrometer. The isotopomers studied include those of H2O, HDO, D2O, H2 17O and H2 18O with the six most abundant isotopes of Kr. A tunnelling splitting due to a large amplitude internal motion of the H2O subunit that exchanges bonded and non-bonded hydrogen atoms was observed. Nuclear quadrupole hyperfine structure was resolved and measured for the complexes containing 83Kr, D, and l7O, and the corresponding nuclear quadrupole coupling constants were determined. These were used to estimate structural parameters and to derive information about the intermolecular dynamics. The results, and in some instances the spectroscopic constants themselves, were compared with experimental and theoretical data previously reported for Ar-H2O. 相似文献