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101.
A. L. Ivanovskii 《Theoretical and Experimental Chemistry》2007,43(1):1-27
The present state of research on the production and modeling of nanostructures based on titanium carbide-a typical representative
of an extensive class of carbides of d-and f-metals-is reviewed. Methods for the synthesis of various Ti-C nanostructures
(molecular clusters, nanocrystallites, nanospheres, nanofibers, nanowires) are examined, and their morphology, atomic structure,
and known physicochemical characteristics are described. Theoretical models of the atomic structure and properties of new
types of nanostructures in the titanium-carbon system (endo-and exohedral titanofullerenes, “hybrid” structures based on carbon
nanotubes, the so-called peapods, nanocables, and a number of others) and the prospects for their application as components
of nanoceramics, hydrogen accumulators, materials for spintronics, etc. are discussed.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 1, pp. 1–23, January–February, 2007. 相似文献
102.
Sang Kyu Lee Min Ju Cho Jung‐Il Jin Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2007,45(3):531-542
New photocrosslinkable maleimide copolymers have been synthesized by the attachment of a tricyanopyrrolidene‐based chromophore. The 2‐(3‐cyano‐4‐(2‐{4‐[hexyl‐(6‐hydroxy‐hexyl)‐amino]‐phenyl}‐vinyl)‐5‐oxo‐1‐{4‐[4‐(3‐oxo‐3‐phenyl‐propenyl)‐ phenoxy]‐butyl}‐1,5‐dihydro‐pyrrol‐2‐ylidene)‐malononitrile chromophore exhibits nonlinear optical activity and contains a chalcone moiety that is sensitive to UV light (λ = 330–360 nm) for crosslink formation. The maleimide monomers have also been functionalized with chalcone moieties. The resultant copolymers exhibit great processability, and one of them shows a maximum electrooptic coefficient of 90 pm/V at 1300 nm. We could control the thermal stability of the electrooptic coefficient with the newly synthesized photoreactive copolymers successfully. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 531–542, 2007 相似文献
103.
104.
Pál Sohár Gábor Bernáth Géza Stájer Angela E. Szabo 《Magnetic resonance in chemistry : MRC》1989,27(9):872-876
Pentacyclic isoxazolines were obtained by the cycloaddition of benzonitrile oxide to norbornene-azetidinone-fused 3,1-oxazines. The constitutions of two of the isomers obtained, and the configurations and conformations of all products, were determined by means of 1H and 13C NMR spectroscopy and DNOE experiments. 相似文献
105.
106.
Wei-Yan Shao Ying-Nan Cao Wen-Jie Pan Xian-Zhang Bu Lin-Kun An Lian-Quan Gu Albert S.C. Chan 《Tetrahedron letters》2006,47(24):4085-4089
Seventeen unsymmetrical curcumin derivatives were synthesized in good yield and purity by a facile solid phase synthesis strategy. 相似文献
107.
王胜奎 《数学的实践与认识》2006,36(5):5-10
根据松纵坑切梢小蠹的主要生物学特征,通过分析抚育间伐持续控制松纵坑切梢小蠹虫害的机理,应用复杂适应系统(CA S)理论,建立了模拟松纵坑切梢小蠹虫害的一种动态演化数学模型,并讨论了模型的收敛性.然后选用昆明小哨林场为背景,进行了各种抚育间伐决策的仿真,从中优选抚育间伐决策.结果表明:模拟优化方案与实际调查统计分析结果一致:均为弱度间伐与中弱度间伐控制蠹害效果最好.最后通过森林积材量与虫害程度之间的优化,给出了抚育间伐的优化策略. 相似文献
108.
GAO Xing-Ru 《理论物理通讯》2006,46(11)
In this paper, we propose a modified traffic model in which a single car moves through a sequence of traffic lights controlled by a step function instead of a sine function. In contrast to the previous work [Phys. Rev. E 70 (2004)016107], we have investigated in detail the dependence of the behavior on four parameters, ω, α, η, and a1, and given three kinds of bifurcation diagrams, which show three kinds of complex behaviors. We have found that in this model there are chaotic and complex periodic motions, as well as special singularities. We have also analyzed the characteristic of the complex period motion and the essential feature of the singularity. 相似文献
109.
110.
合成了两种新型噻吩基卟啉-5,15-二(2-噻吩基)-2,8,12,18-四乙基-3,7,13,17-四甲基卟啉7a(45.1%)和5,15-二(2-联噻吩基)-2,8,12,18-四乙基-3,7,13,17-四甲基卟啉7b(61.2%),并研究了它们的光谱性质,其中荧光光谱的最大发射峰蜂都在631nm处,量子产率分别为4.1%(7a)和1.4%(7b)。 相似文献