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971.
宋慧瑾 Zheng Jiagui FengLianghuan Yan Qiang Lei Zhi Wu Lili Zhang Jingquan Li Wei Li Bing 《高技术通讯(英文版)》2008,14(1):57-60
CdS/CdTe solar cells with ZnTe/ZnTe:Cu buffer layers were fabricated and studied. The energy band structure of it was analyzed. The C-V, I-V characteristics and the spectral response show that the ZnTe/ZnTe:Cu buffer layers improve the back contact characteristic properties, the diode characteristics of the forward junction and the short-wave spectral response of the CdTe solar cells. The ZnTe/ZnTe:Cu buffer layers affect the solar cell conversion efficiency and its fill factor. 相似文献
972.
In order to evaluate the cytocompatibility and biocompatibility of a new kind of chitosan blend film as a carrier of corneal endothelial cell, rabbit corneal endothelial cells cultured in vitro were breeded onto the film. After a cell monolayer formed, the scanning electron micrography was performed. After inplanted into anterior chamber, slit lamp observation, thickness metering, specular microscopy and HE staining were performed at random time after operation to evaluate the biocompatibility. Inflammation in anterior, thickness of cornea, cell density, hexagonality and cell size of the surgical cornea were taken as the indexes of biocompatibility. The cultured cells exhibited a confluent monolayer 10 days after incubation, which proved the satisfactory cytocompatibility of this film. Biocompatibility assay results suggested the implantation feasibility of the film as a carrier of corneal endothelial cells. 相似文献
973.
目的:研究红景天苷对骨髓间充质干细胞(Bonemesenchymalstemcells,BMSCs)生物学活性影响。方法:采用贴壁法分离培养BMSCs,检测细胞表面分子表达对所获干细胞进行鉴定。以终浓度为10¨g/mL红景天苷与BMSCs共培养,通过形态学观察和MTT法分析研究其对BMSCs生物学特性影响。结果:成功培养出BMSCs,免疫荧光染色显示,培养的第3代BMSCs表达CD29、CD44干细胞标志。10μg/mL红景天苷与BMSCs共培养后,较对照组细胞生长更为旺盛,更为规整,形成典型的“鱼群状”。生长曲线显示,实验组细胞较对照组生长稳定,增殖能力活跃。结论:10μg/mL红景天苷可促进BMSCs增殖分化,又不影响细胞增殖分化等生物学特性。 相似文献
974.
在精切削加工时,为什么采用极低或高速切削时工件表面粗糙度低?为什么采用润滑性能好的切削液、刀具前角大、进给量和刀具主偏角小工件表面粗糙度低?为什么工件材料硬度高、脆性大的材料,在切削时粗糙度低?等等。怎么保证加工质量,值得深思。本文论述了在切削塑性材料过程中一种常见的物理、力学作用下,积屑瘤的生长条件,消失、防止措施,及对精加工表面粗糙度产生的影响。 相似文献
975.
《自然科学进展(英文版)》2020,30(6):912-917
Charge transport processes involving the proton migration and electron transfer for different parts of membrane electrode assemble (MEA) play an essential role for developing the novel electrode and enhancing the electrochemical performance towards proton exchange membrane fuel cells (PEMFCs). However, the coupled charge transport processes make it difficult for evaluating proton conductivity and electronic conductivity of different parts in MEAs under operation conditions of fuel cells. Here in this work, we propose an experiment approach for separating the electronic conductivity and proton conductivity of different components of MEA at the operating conditions of PEMFCs. This approach involves two different measuring devices, which both consist of electron or proton conducting layers, sealing layers and sample layer, followed by tailoring the thickness of sample layers and via electrochemical impedance spectroscopy (EIS) to quantity the electronic conductivity and proton conductivity of different layers. These experiment results show the great potential in the development of different components of MEA. 相似文献
976.
龙葵碱对肿瘤细胞膜ATP酶活性的影响 总被引:7,自引:0,他引:7
荷瘤小鼠分为治疗组(37.50mg/kg、18.75mg/kg、9.37mg/kg)和对照组(生理盐水组、环磷酰胺组30mg/kg),分别测定各组肿瘤细胞膜的Na^ ,K^ -ATPase及Ca^2 ,Mg^2 -ATPase活性.结果表明龙葵碱(37.50mg/kg、18.75mg/kg)对S180小鼠及H22小鼠肿瘤细胞膜Na^ ,K^ -ATPase及Ca^2 ,Mg^2 -ATPase活性均有明显的抑制作用,并且其抑制作用呈量效正相关.因此龙葵碱这一作用可能是其抗肿瘤作用机理之一. 相似文献
977.
将人生长激素hGH的cDNA片段克隆在转移载体pVL1393的多角体蛋白基因启动子下游,构成重组转移载体pVL1393hGH,将该质粒DNA与昆虫杆状病毒(AcNPV)DNA共转染秋粘虫(Spodopterafrugiperda)细胞Sf9,通过体内同源重组,hGH基因取代多角体蛋白基因,从而整合到病毒基因组上,经感染昆虫细胞后表达外源hGH基因,通过反复病毒空斑纯化,获不含多角体的重组病毒,利用免疫化学发光法测定hGH表达量达40μg/mL. 相似文献
978.
Arshad Mahmoo R. Rashi U. Aziz A. Shah Zahid Ali Qaiser Raz Tanveer Ashraf 《自然科学进展(英文版)》2015,25(1):22-28
Zn1-xNixTe thin films with different composition(x=0.0, 0.05, 0.10, 0.15 and 0.20) were deposited on glass substrate by electron beam evaporation technique followed by its characterization using advanced structural and optical analysis techniques. Structural properties of the prepared thin films were studied by X-ray diffraction(XRD). The XRD patterns revealed that the binary compounds transformed into a ternary compound with cubic structure having preferred orientation along the c-direction with(111) planes. Composition analysis of the films was determined by energy dispersive analysis of X-rays(EDAX) and found to be in agreement with the precursor composition. Optical properties such as extinction coefficient(k) and band gap energy of these films were examined by using a spectroscopic ellipsometer. It was found that the extinction coefficient(k) increased with the addition of Ni content in the alloy. In comparison, the band gap energy was also determined by using transmission spectra and found to be agreed with that of the ellipsometric results. These analyses confirm that the band gap energy decreases with the increase of Ni content in the alloy. 相似文献
979.
控压钻井井控是处理气侵溢流问题的有效新方法,包括前期控制和循环排气两个阶段。基于快速施加井口回压控制方法,根据气液固多相流理论,建立控压钻井井控数学模型,并采用有限差分法迭代求解。在此基础上,分析排量对最大井口回压、最大套管鞋处压力和最大立管压力的影响,并提出基于井控安全目标函数的排量优化设计方法。模拟结果表明:在循环排气阶段,立管压力维持不变且为最大值,井口回压达到最大值与气体前沿运移到井口之间存在明显的时间滞后性,气体运移到套管鞋处时套管鞋处压力最大;验证了以出入口流量一致表征井底气侵停止的合理性。模型计算得到的压力值与实验测量值吻合较好。 相似文献
980.
红耳龟嗜银细胞见于消化道全长,其分布曲线大体呈倒“V”字型,其中食道嗜银细胞分布密度最低,幽门分布密度最高,以后各部分布密度依次降低.嗜银细胞分布于粘膜上皮之间或腺泡上皮之间,也有少量位于固有层和上皮细胞基部.嗜银细胞形态多种多样呈圆形、椭圆形、锥体形等,其中锥体形嗜银细胞突起伸向肠腔、固有层或腺泡腔. 相似文献