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991.
§1IntroductionLetGbeaconnectedgraphwithvertex-setV(G)andedge-setE(G).Denotebye=(x,y)theedgejoiningtheverticesxandyofG.Am-cliq... 相似文献
992.
Guo‐Cang Wang Jian Xiao Yong‐Na Lu Lin Yu Hai‐Bin Song Jin‐Shan Li Jing‐Rong Cui Rui‐Qing Wang Fu‐Xiang Ran Hong‐Gen Wang 《应用有机金属化学》2005,19(1):113-117
Four novel triarylbismuth(V) di(N‐salicylidene)amino carboxylates were synthesized. Their structures were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. The crystal structure of (2‐HOC6H4CH?NCH2CO2)2BiPh3 was determined by X‐ray diffraction. The in vitro cytotoxicity of all compounds against three human cancer cells (HL‐60, BGC‐823 and MDA‐MB‐435) at 10 µM are reported. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
993.
Mei SHI Xiang Hong LI Fu You LI Deng Qing ZHANG Bing Bing DAI Tao YI Chun Hui HUANG 《中国化学快报》2006,17(1):69-72
Design and synthesis of new chemosensors for fluoride anion (F-)1-6 have been of interest to chemists for many years, because F- plays a crucial role in the dental care5 and the treatment of osteoporosis7. Recently, the fluorescent chemosensors of fluorid… 相似文献
994.
We put forward a kind of tunable external cavity semiconductor laser with feedback on both chip facets. It outputs the single-frequency laser with high side-mode suppression ratio and the frequency could be step tuned. 相似文献
995.
An experimental study was carried out for the cyclic properties of pure aluminium subjected to uniaxial cyclic straining and stressing. For a material of pure aluminium the effects of the cyclic strain amplitude history and mean strain on the cyclic deformation behavior were investigated, and the influences of stress amplitude, mean stress and their histories on cyclic creep (i. e., ratcheting) were analyzed. It is shown that either uniaxial cyclic property under cyclic straining or ratcheting behavior under asymmetric uniaxial loading depends not only on the current loading, but also on the previous loading history. Some significant results were obtained.Financial support from NFSC is acknowledged. 相似文献
996.
997.
Xiang Hongjun Wang Jinhua Chen Anping 《Annals of Differential Equations》2005,21(4):604-615
In this paper, a class of two-dimensional shunting inhibitory cellular neural networks with distributed delays and variable coefficients system is studied. By using the Schauder's fixed point theorem and Lyapunov function, we obtain some sufficient conditions about the existence and attractivity of almost periodic solutions to the above system, and all its solutions converge to such almost periodic solution. An example is given to illustrate that the conditions of our results are feasible. 相似文献
998.
Xiang Fang 《Journal of Functional Analysis》2003,198(2):445-464
We define and study Hilbert polynomials for certain holomorphic Hilbert spaces. We obtain several estimates for these polynomials and their coefficients. Our estimates inspire us to investigate the connection between the leading coefficients of Hilbert polynomials for invariant subspaces of the symmetric Fock space and Arveson's curvature invariant for coinvariant subspaces. We are able to obtain some formulas relating the curvature invariant with other invariants. In particular, we prove that Arveson's version of the Gauss-Bonnet-Chern formula is true when the invariant subspaces are generated by any polynomials. 相似文献
999.
Fei Lu Ming Qi Meng Ke Ming Wang Feng Xiang Wang Wei Li Lu Zhong Cai Yu Rong Wang Huan Chu Chen Ding Yu Shen 《Optics Communications》1997,140(4-6):204-206
The first H-ion implanted Cu-doped (K0.5Na0.5)0.2(Sr0.75Ba0.25)0.9Nb2O6 crystal planar waveguide is reported in this paper. Low dose MeV H ion implantation into a crystal of KNSBN has been used to fabricate the waveguide by generating a buried layer of lowered refractive index. Both TE and TM modes are observed. The reconstructed refractive index profiles in the waveguide are obtained using a parametrized index profile reconstruction method. The simulated results of TRIM show that the nuclear collision influences most the ordinary index profile, but in the region of the guide the extraordinary index profile may be related to the electronic energy loss. 相似文献
1000.
5种重要农艺性状基因在水稻重组自交系群体中的定位 总被引:7,自引:0,他引:7
通过抗病虫害水稻品系“B5”与籼稻品种“明恢63”为亲本进行杂交,得到一个187个F8代的重组自交系群体。利用重组自交系群体构建的分子连锁图,对水稻抽穗期、株高、穗长、剑叶长和剑叶宽的性状进行了QTL分析,分别检测到影响抽穗期、株高、穗长、剑叶长和剑叶宽的农艺性状2、2、4、4、4个QTLs,并分别解释各表型性状总变异的50.6%、74.9%、34.1%、47.3%和46.2‰.其中,控制抽穗期的Hd-6基因,控制株高的Ph7基因和控制剑叶长的Fll-2b基因分别是效应值较大的主效座位,其余的为微效基因座位。相关性状的QTLs大多聚集在染色体的相近或相同区间,表现出成簇分布的现象。这些重要农艺性状的分析,可以为水稻分子标记辅助选择育种提供有用的遗传信息。 相似文献