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991.
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994.
SUN ChuanFu YANG BingPing & MAO JiangGao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou China 《中国科学B辑(英文版)》2011,(6)
Metal iodates with a lone-pair containing I(V) that is in an asymmetric coordination geometry can form a diversity of unusual structures and many of them are promising new second homonic generation (SHG) materials. They exhibit wide transparency wavelength regions, large SHG coefficients and high optical-damage thresholds as well as moderately high thermal stability. In this paper, the structures and properties of the metal iodates are reviewed. The combination of d0 transition-metal cations with the iodate... 相似文献
995.
By AM1 method, the interactions between 1, 3-N, N′-Bis-4-(4′-nitro benzenediazo) phenyl squaraine (BNBPS) and several oxoacid anions have been studied on the basis of the proposed model. The mechanism of the color reactions is suggested and the answers to the question of whether or not BNBPS colorates with HCO_3~-, CO_3~(2-), NO_2~(-), NO_3~-, etc. are given. It is theoretically predicted that BNBPS might be used as the color reagent for SO_4~(2-). 相似文献
996.
铈铝复合载体对钼基催化剂耐硫甲烷化催化性能的研究 总被引:2,自引:0,他引:2
铈铝复合载体对钼基催化剂耐硫甲烷化催化性能的研究 《燃料化学学报》2012,40(11):1390-1396
采用共沉淀法、浸渍法和沉积沉淀法制备了CeO2-Al2O3复合载体,比较了不同复合载体浸渍钴钼后的耐硫甲烷化催化性能,并优化了复合载体中CeO2的含量。结合N2物理吸附、XRD、H2-TPR等表征手段对复合载体及其负载的钴钼催化剂进行物相和结构分析发现,在Al2O3中添加CeO2可以明显提高合成气的耐硫甲烷化活性,其中,沉积沉淀法制备的25% CeO2-Al2O3复合载体负载钴钼后具有最佳催化活性。 相似文献
997.
The title complex,[Ag2(L1)2(Pyr)·2.5H20]1(L1=6-amino-1-naphthalenesulfonate anion,Pyr=pyrazine),has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1,with a=7.339(5),b=13.105(5),c=14.097(5)(A),α=84.377(5),β=76.921(5),γ=79.628(5)°,V= 1296.7(11)(A°)3,C48H50Ag4N8O17S4,Mr =1570.68,Z=1,Dc=2.011 g/cm3,/μ= 1.732 mm-1,F(000)=782,S=1.148,the final R=0.0436 and wR=0.1181 for 4130 observer reflections(I>20(I)).Compound 1 shows a rare one- dimensional(1D)double chain, and the chains are further connected through secondary bonding,hydrogen bonds, and π-π interactions to generate a three-dimensional(3D)supramolecular structure.The luminescent property of 1 was also studied in the solid state at room temperture. 相似文献
998.
一类不连续Strum-Liouville问题特征函数的振动性 总被引:1,自引:0,他引:1
研究了-类不连续的Sturm-Liouville问题在开区间(a,c)u(c,b)上特征函数的振动性.构建了一个与其相关的新的Hilbert空间,证明了具有分离边界条件的这类问题的第n个特征值λn(n=1,2,…)所对应的特征函数在区间(a,c)U(c,b)上恰有n-1个零点. 相似文献
999.
1000.
To explain the long-term existence of Uranian narrow rings, we study the dynamical evolution of Uranian epsilon ring under
the influence of its two shepherding satellites: Cordelia and Ophelia. The model of planar-elliptic restricted three-body
problem is employed, in which the three bodies are Uranus, a satellite and a test particle. Dissipations due to interparticle
collisions are also taken into consideration. A mapping system has been obtained based on the differential equation system.
Numerical results show that only those particles originally lying in the libration region of the resonance can be shepherded.
The size of the libration region depends mainly on the orbital eccentricity and mass of the shepherd satellite. For the outer
shepherd Ophelia with larger orbital eccentricity, if its mass is a third of the nominal mass 2.5 × 1019 g, most of the orbits are regular and the outer edge of the ring can be shepherded, but more fuzzy than the inner edge. Thus
we infer that Ophelia has a smaller mass. 相似文献