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FU105大功率广播发射管用碳化镧钼阴极研究

万小峰 , 张久兴 , 周文元 , 李湘波 , 周美玲

稀有金属材料与工程

研究了FU105大功率广播发射管用碳化镧钼阴极,参照碳化钍钨阴极FU105管的制备工艺,实现了镧钼阴极的碳化以及镧钼阴极FU105管的排气和老炼.通过镧钼阴极FU105管的性能测试,对碳化镧钼阴极的发射能力和稳定性进行了分析.结果认为:FU105管碳化镧钼阴极的发射能力可以达到碳化钍钨阴极的水平,但其稳定性还有待改进.

关键词: 镧钼阴极 , FU105发射管 , 碳化 , 稀土

Studies of the anion position parameter chi of the ternary semiconductor CuGaS2 by use of Ni+ ion probe

Materials Science and Engineering B-Solid State Materials for Advanced Technology

The anion position parameter chi of NiS4 cluster formed in the ternary semiconductor CuGaS2 by substitution of Ni+ for Cu+ has been determined by studying the optical spectra and EPR data for CuGaS2:Ni+. The result (chi approximate to 0.263(1)) is consistent with the mean value of the X-ray measurement results reported in two groups of references and also with the calculated value obtained from the conservation of tetrahedral bonds (CTB) plus eta = eta(tet) rule (where eta = c/2a). So, we suggest that the anion position parameter chi in pure CuGaS2 crystal is close to the above value obtained by use of Ni+ ion probe. The optical absorption bands and g factors g(parallel to), g(perpendicular to), of CuGaS2: Ni+ are therefore explained reasonably from the anion position parameter. (C) 2003 Elsevier B.V. All rights reserved.

关键词: structural parameter;electron paramagnetic resonance (EPR);optical;spectrum crystal-field theory;CuGaS2;Ni+;chalcopyrite semiconductors;superposition model;crystal

Two-step magnetization in a spin-chain system on the triangular lattice: Wang-Landau simulation

Physical Review B

The Wang-Landau algorithm is used to study the thermodynamic and magnetic properties of triangular spin-chain system based on two-dimensional Ising model in order to understand the magnetic-order dynamics in Ca(3)Co(2)O(6) compound. The calculated results demonstrate that the equilibrium state of the rigid spins produces the two-step magnetization curve at low temperature even when the random-exchange term is considered. This work indicates that the four-step magnetization behavior observed experimentally must be due to the nonequilibrium magnetization.

关键词: calcium compounds;exchange interactions (electron);Ising model;magnetisation;thermodynamics;one-dimensional ca3co2o6;density-of-states;compound ca3co2o6;phase-diagram;proteins;crystal

[Pt(en)(5-Fu)2]Cl2配合物的合成及抗肿瘤活性

钟文远 , 崔永春 , 范春兰 , 胡智兴 , 李玛琳

贵金属 doi:10.3969/j.issn.1004-0676.2004.02.005

为寻求高效低毒的新型顺铂类抗肿瘤药物,用K2PtCl4、乙二胺(en)、氟尿嘧啶(5-Fu)为原料,设计合成了顺铂类似物[pt(en)(5-Fu)2]C12配合物,由元素分析、红外光谱和质谱分析初步证实了其化学结构,用改良MTT、SRB法,选用K562、A549、Bel-7402、BIU-87、Bcap-37细胞株对其进行体外抗肿瘤活性测定.结果表明,所合成的配合物除在浓度为0.01、0.1 μg/mL时对K562细胞株抗肿瘤活性大于顺铂和氟尿嘧啶外,其它情况下的抗肿瘤活性均小于顺铂和氟尿嘧啶.该配合物仍有进一步研究的价值.

关键词: 药学 , 铂(Ⅱ)配合物 , 合成 , 抗肿瘤活性

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

聚天冬氨酸交联温敏性水凝胶的药物缓释性能

于跃芹 , 常宪智 , 田红杰 , 许洋

高分子材料科学与工程

选用牛血清蛋白(BSA)和5-氟尿嘧啶(5-FU)为模型药物,以聚天冬氨酸交联温敏性水凝胶为载体材料,采用包埋法制备了载药水凝胶,研究了水凝胶的载药和释药性能.水凝胶对BSA和5-FU的包埋率均大于98%.37℃时,水凝胶中丙烯酸用量越大,BSA的释放率越低;交联剂用量对BSA的释放率无显著影响.25℃时,丙烯酸用量越大,5-FU的释放率越大;交联剂用量越大,5-FU的释放率越小.37℃时,丙烯酸用量越小,5-FU的释放率越大;交联剂用量越大,5-FU的释放率越小.

关键词: 温敏性水凝胶 , 药物缓释 , 5-氟尿嘧啶 , 牛血清蛋白

磁性壳聚糖-5-氟尿嘧啶纳米粒的制备及体外释药性能

李和平 , 肖华伍 , 肖子丹 , 阮建明

高分子材料科学与工程

采用交联-聚合法在超声波的作用下,制备了磁性壳聚糖-5-氟尿嘧啶纳米粒(MCN-Fu).透射电子显微镜(TEM) 和红外光谱(IR)等分析结果表明,MCN-Fu粒子外形规整,分散性好,粒径主要在50 nm~60 nm 之间.紫外-可见光谱分析结果表明,MCN-Fu的载药量为21.3%,在磷酸盐缓冲溶液(pH=7.2)中,30 h的累积释药率为67.6%,具有良好缓释性能,并具有良好磁响应性能.

关键词: 磁性 , 壳聚糖 , 氟尿嘧啶 , 纳米粒 , 药物缓释剂

Influences of variations of characteristic parameters of protein molecules on states of soliton transported bio-energy

International Journal of Modern Physics B

We simulate numerically the dynamic properties of new soliton with quasi-coherent two quanta in the improved model by fourth-order Runge-Kutta way. We observed that the window of formation of new soliton is shifted toward smaller values of coupling constants when compared with the Davydov's soliton with one quantum and Forner's soliton with two quantum model. The new soliton formation starts at (chi 1 + chi 2) = 20 PN, and pinning starts from (chi 1 + chi 2) = 86 PN. The pinned solitons are also observed if both quanta are on the same end of the chain in the initial state. The behaviors of new soliton are varied under influences for variations of characteristic parameters arising from the structure nonuniformity of protein molecules. Although the new soliton is also sensitive to the dipole-dipole interaction and diagonal disorder, the sensitivity to the impurity is weaker than that of the Davydov's and Forner's solitons. Therefore, the new soliton is robust against the fluctuations of coupled constant, dipole-dipole interaction and diagonal disorder arising from the impurity or structure nonuniformity, when compared with that of the Davydov's and Forner's solitons.

关键词: protein;bio-energy transport;soliton;structure nonuniformity;characteristic parameter;davydov soliton;living systems;improved model;thermodynamic;properties;biological temperature;finite-temperature;quantum;dynamics;disorder;lifetime

5-氟尿嘧啶载药微球的制备工艺及性能研究

李航 , 袁华 , 仲谦 , 任杰

功能材料

以PLA为载体材料,以5-Fu为模型药物,制备5-Fu/PLA载药微球,通过正交设计优化微球制备工艺.另外,检测了载药微球的回收率、稳定性、缓释性能等物理性质.用紫外分光光度计测定药物含量,激光粒度仪分析粒径. 结果表明,载药微球的平均粒径为(133.2±32.5)nm,平均包封率为(11.3±5.0)%,缓释时间延长至80~100h,具有良好的缓释功能.

关键词: 正交试验法 , 聚乳酸 , 溶剂挥发法 , 体外缓释

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