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S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
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Barron JA Glazier S Bernhard S Takada K Houston PL Abruña HD 《Inorganic chemistry》2003,42(5):1448-1455
The absorption and emission spectra, excited-state lifetimes, quantum yields, and electrochemical measurements have been obtained for a new series of chiral complexes based on three different chiral 2,2':6',2' '-terpyridine ligands, (-)-ctpy, (-)-[ctpy-x-ctpy], and (-)-[ctpy-b-ctpy], with one, two, or multiple Ru metal centers. The room-temperature absorption and emission maxima of [[((-)-ctpy)Ru]-(-)-[ctpy-b-ctpy]-[Ru((-)-ctpy)]](PF(6))(4) and ((-)-[ctpy-b-ctpy])-[[Ru((-)-[ctpy-b-ctpy])](PF(6))(2)](n) were shifted to lower energies and also exhibited significantly longer luminescence lifetimes when compared to [Ru((-)-ctpy)(2)](PF(6))(2), [[((-)-ctpy)Ru]-(-)-[ctpy-x-ctpy]-[Ru((-)-ctpy)]](PF(6))(4), and ((-)-[ctpy-x-ctpy])-[[Ru((-)-[ctpy-x-ctpy])](PF(6))(2)](n). In terms of their electrochemical behavior, all of the complexes studied exhibited one Ru-centered and two ligand-centered redox waves and the [[((-)-ctpy)Ru]-(-)-[ctpy-x-ctpy]-[Ru((-)-ctpy)]](PF(6))(4), ((-)-[ctpy-x-ctpy])-[[Ru((-)-[ctpy-x-ctpy])](PF(6))(2)](n), and ((-)-[ctpy-b-ctpy])-[[Ru((-)-[ctpy-b-ctpy])](PF(6))(2)](n)() complexes were found to electrodeposit upon ligand-based reduction. The difference between the formal potentials of the Ru-centered and the first ligand-centered (least negative) waves corresponded linearly with the changes in the observed emission energies. The shifts in energy are discussed using a particle-in-a-box model, and the luminescence lifetimes are discussed in terms of the structure of the excited-state manifold. 相似文献
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The spectrum and properties of the excited states of the nucleon are still poorly established despite decades of study. These proceedings describe new measurements of pseudo-scalar meson photoproduction at the Crystal Ball at MAMI, employing a new large acceptance nucleon recoil polarimeter. The double- and single-polarisation observables obtained will provide valuable and unique data to be used as part of the world effort to improve our knowledge of this fundamental spectrum. 相似文献
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The photoproduction of K+ mesons from the nucleon provides important constraints on the nucleon excitation spectrum and at threshold energies challenges effective field theories based on chiral perturbation in the strange quark sector. Preliminary cross-section measurements for γ(P, K+)A are presented at an unprecedented beam energy resolution. The data was collected at the MAMI-C facility in Mainz using the Crystal Ball Detector. A new method of K+ detection was used in which the K+ is tagged from its weak decay products in the detector crystals. This technique has application with other calorimeters at present and future hadron facilities. 相似文献
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D. I. Glazier M. Seimetz J. R. M. Annand H. Arenhövel M. Ases Antelo C. Ayerbe P. Bartsch D. Baumann J. Bermuth R. Böhm D. Bosnar M. Ding M. O. Distler D. Elsner J. Friedrich S. Hedicke P. Jennewein G. Jover Ma nas F. H. Klein F. Klein M. Kohl K. W. Krygier K. Livingston I. J. D. MacGregor M. Makek H. Merkel P. Merle D. Middleton U. Müller R. Neuhausen L. Nungesser M. Ostrick R. Pérez Benito J. Pochodzalla Th. Pospischil M. Potokar A. Reiter G. Rosner J. Sanner H. Schmieden A. Süle Th. Walcher D. P. Watts M. Weis 《The European Physical Journal A - Hadrons and Nuclei》2005,24(1):101-109
The electric form factor of the neutron, GE,n, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(¯e, e¯n)p reaction. Three data points have been extracted at squared four-momentum transfers Q
2 = 0.3, 0.6 and 0.8 (GeV/c)2. Corrections for nuclear binding effects have been applied.This revised version was published online in March 2005. In the previous version, the email address of one author was inadvertently assigned to multiple authors. 相似文献
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We argue that energy minimization can explain the pattern of cell movements in the morphogenetic process known as convergent extension provided that the cell-cell adhesive energy has a certain type of anisotropy, which we describe. This single simple property suffices to cause the cell elongation, cell alignment, and lengthening of a cellular array that characterize convergent extension. We show that the final aspect ratio of the array of cells depends on the anisotropy and is independent of the initial configuration and of the degree of cell elongation. 相似文献
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利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
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