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131.
132.
离子凝聚法制备负载流感疫苗的壳聚糖微球 总被引:2,自引:1,他引:1
采用三聚磷酸钠(TPP)作为离子交联剂, 应用离子凝聚法制备负载流感疫苗的壳聚糖微球. 筛选出壳聚糖起始质量分数为1%. TPP的浓度对壳聚糖微球的制备影响较大, 采用低浓度的TPP(200 μg/mL)制备的微球放置过夜均出现沉淀现象, 高浓度的TPP(800 μg/mL)在制备过程中出现絮状沉淀. 固化比影响微球的释放行为, 固化比为1∶1的微球爆炸式释放率达到90%, 固化比为1∶3的微球6 h后逐步释放, 12 h后释放率达到95%. 固化比为1∶5的微球6 h后没有明显的释放行为. 壳聚糖溶液的pH对微球的制备和释放没有显著的影响. 通过对负载流感疫苗的壳聚糖微球的制备条件和释放行为的研究结果表明, pH=5.6的壳聚糖溶液, 固化比为1∶3, TPP的质量浓度为400 μg/mL是较理想的流感疫苗壳聚糖微球的制备条件. 相似文献
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曹学香 李卫东 Roy A. Briere 刘春雷 毛泽普 陈申见 邓子艳 何康林 黄性涛 黄彬 黄艳萍 贾卢魁 季晓斌 李秀荣 刘春燕 刘怀民 马秋梅 马想 邱进发 王大勇 伍灵慧 吴智 袁野 张学尧 赵川 张瑶 邹佳恒 《中国物理 C》2010,34(12):1852-1859
The Beijing Spectrometer Ⅲ(BESⅢ)is a general-purpose detector used for the study of τ-charm physics at the Beijing Electron-Positron Collider Ⅱ(BEPC Ⅱ).This paper presents our studies of the dE/dx measurement in the drift chamber of BESⅢ,which is important for the identification of charged particles.Corrections applied to the dE/dx measurement in data reconstruction are discussed.After our current dE/dx calibration,a resolution of about 6% has been obtained for minimum ionization particles,and a 3σ K/πseparation is obtained for momenta up to 760 MeV/c.These results meet the design goals of the BESⅢ drift chamber. 相似文献
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七种不同产地仙鹤草原药材及提取物的红外光谱与二维相关红外光谱的分析与鉴定 总被引:4,自引:0,他引:4
采用红外光谱、二阶导数红外光谱以及二维相关红外光谱,对七种不同产地的仙鹤草原药材及其总鞣酸提取物进行了鉴别分析。仙鹤草原药材的红外光谱中出现了1 151,1 101,1 032 cm-1的淀粉特征峰,同时还出现了1 618,1 318,780 cm-1的草酸钙特征峰,说明在原药材粉末中同时有淀粉和草酸钙存在。原药材丙酮提取物中所含淀粉等基本成分大为减少,而总鞣酸等有效成分的相对含量增加,因此不同产地仙鹤草丙酮提取物的红外光谱中均出现1 711与1 447 cm-1的鞣酸特征峰。应用红外光谱、二阶导数红外光谱以及二维相关红外光谱技术,不仅可以提供仙鹤草主要化学成分的相关信息,还可以对不同产地的仙鹤草药材进行很好的区分。因此红外光谱法是考察中药资源的一种快速、准确、有效的方法。 相似文献
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ZHANG Huan-Qiao LIN Cheng-Jian YANG Feng JIA Hui-Ming ZHOU Ping AN Guang-Peng ZHANG Chun-Lei XU Xin-Xing 《中国物理C(英文版)》2010,34(10)
An electrostatic deflector for separating the fusion evaporation residues from the beam-like products in heavy ion reactions was installed.The evaporation residue separation and identification with the electrostatic deflector setup was tested with the reaction 32S+96Zr at several energies.The fusion evaporation residues and the beam-like particles were well separated after the electrical separation and the experimental fusion cross section obtained from the angular distribution is in good agreement with the calculated value well above the Coulomb barrier.This confirms the reliability of the setup. 相似文献
138.
Dependence of bulk modulus on both pressure and temperature, the elastic constants Cij and the pressure and temperature dependence of normalized volume V/Vo of cubic Ni2MnGa alloy are successfully obtained using the first-principles plane-wave pseudopotential (PW-PP) method as well as the quasi-harmonic Debye model. We analyse the relationship between bulk modulus and temperature up to 800 K and obtain the relationships between bulk modulus B and pressures at different temperatures. It is found that the bulk modulus B increases monotonically with increasing pressure. Moreover, the temperature dependences of the Debye temperature are also analysed. The calculated results are in agreement with the available experimental data and the previous theoreticM results. 相似文献
139.
Cu Doping Effect on Electrical Resistivity and Seebeck Coefficient of Perovskite-Type LaFeO3 Ceramics
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WANG Hong-Chao WANG Chun-Lei ZHANG Jia-Liang ZHAO Ming-Lei LIU Jian SU Wen-Bin YIN Na MEI Liang-Mo 《中国物理快报》2009,26(10)
Perovskite-type LaFe1-xCuxO3 (x=0.10$, 0.14, 0.18) solid solution is prepared with the conventional solid-state reaction technique. The electrical resistivity and the Seebeck coefficient are measured in the temperature range 473-1073K to elucidate the Cu doping effect on the thermoelectric properties of the LaFeO3. The electrical resisitivity of LaFe1-xCuxO3 shows semiconducting behavior. The temperature dependence of the electrical resistivity indicates that the adiabatic small-polaron hopping mechanism is dominant for their electric transportations. The activation energy decreases with the increasing Cu content as well as the increasing temperature. The Seebeck coefficient changes from a negative value to a positive value around 510K, and increases with rising temperature up to 710K, then becomes saturated around 200μV/K. The Seebeck coefficient decreases with the substitution of Cu atoms in the temperature range of 573-1073K, while the electrical resistivity decreases with the substitution of Cu atoms in the whole measured temperature. Overall the power factor increases with rising temperature, and the highest value of power factor is 54μW/K2m for x=0.10 of Cu doping. 相似文献
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