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61.
Ni-SDC固体氧化物燃料电池阳极的合成和性质   总被引:4,自引:0,他引:4  
采用柠檬酸-硝酸盐溶胶-凝胶低温自蔓延燃烧法制备氧化镍(NiO)粉末和Ce0.8Sm0.2O1.9(SDC)粉末,并将NiO与SDC按不同质量比和不同制备工艺制备了固体氧化物燃料电池(SOFC)的阳极前身。再用自组装的还原装置将其在820℃经2.5h还原后,采用四端子法测量其电导率值。分析了阳极片电导率与阳极片微结构、Ni的质量百分数、混合研磨时间及烧结温度之间的关系。结果显示,阳极片的电导率强烈依赖于镍含量和制备工艺。  相似文献   
62.
本文研究了用长光路光度法测定痕量硒。在酸性溶液中,Se(Ⅳ)催化KClO3氧化苯肼成偶氮离子,继而与变色酸生成红色偶氮化合物。硒含量在1.0×10-9~2.0×10-7g/mL范围内遵守比尔定律。巯基棉分离后,测定中药材中总硒,获得满意结果。  相似文献   
63.
以合成的氯代二异丙基膦为原料, 利用电化学全氟化方法, 得到全氟二异丙基膦酸锂(Li[(C3F7)2PF4]), 并对其物理和电化学性能进行了研究.  相似文献   
64.
1 INTRODUCTION Hexamethylenebis[acetamide] (HMBA) is an effective agent in phaseⅡclinical trial[1] that induces differentiation of certain types of tumors to nonmalignant phenotypes. In an attempt to discover more efficient inducers, a number of derivatives of HMBA have been synthesized and evaluated in vitro[2, 3]. The results proved that increasing the number of functional groups could enhance the anticancer activity. In addition, it was evident that compounds with six methylene i…  相似文献   
65.
卟啉类光敏剂在染料敏化太阳能电池中的应用   总被引:5,自引:0,他引:5  
染料敏化太阳能电池结合了染料光敏剂和无机半导体的优势,具有较宽的光谱响应范围,制造工艺简单、成本较低,对环境友好,应用前景广阔,因而备受人们的关注。本文以卟啉配合物为主线,介绍光敏太阳能电池的基本构造和光电原理,从改善电池性能的角度,综述了各种卟啉类光敏剂在染料太阳能电池中的应用,讨论了卟啉配合物及其超分子结构对光电转化率的影响机理。  相似文献   
66.
A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed for the simple and rapid determination of tumor cells. The present system consists of a CCD image sensor, image memory board, personal computer, and microscope. When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis, a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored before reaction. L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation of the whole system is possible.  相似文献   
67.
Glycine max was used as a model plant cell suspension culture to establish relationships among growth kinetics, phenolics production, elicitor action, and peroxidase activity. Timing of elictor addition through monitoring of peroxidase provided an excellent means of optimizing yields of phenolics and reduced the time span during which phenolics were formed, negating the need for a secondary production medium. We have also determined that calcium and other cellular effectors like polyamines and organic osmolytes, when used in conjunction with elicitors, enhance phenolics production. Calcium directly enhanced elicitation, whereas polyamines and other osmolytes such as glycerol and proline extended cell viability. The study also demonstrated potential for enhancing secondary metabolite production by a combination of elicitation, cell viability stabilizers, and by addition of nutrients at the time of elicitation.  相似文献   
68.
The single crystal and crystallized powder of triphosphate CeP3O9 have been synthesized, and the space group of CeP3O9 has been determined to be C2221 with the cell parameters ofa = 8.6059, b = 11.2437, c = 7.3518 (A), V= 711.4(3) (A)3, Z= 4, Dc = 3.520 g/cm3, F(000) = 700,R = 0.0377 and wR = 0.0930. The absorption and emission spectra have been measured, for which the strongest absorption and emission peaks are located at 280 and 320 nm, respectively. The density of state (DOS) and dielectric function have been calculated by the DFT method. The crystal is transparent provided the wavelength is larger than 341 nm, and the observed ultraviolet cut-off edge is at about 350 nm for a polycrystalline power sample. It is possible that the triphosphate CeP3O9 will become an ultraviolet emission material.  相似文献   
69.
The density of neutral oxygen atoms in the MESOX set-up, one device of the PROMES-CNRS solar facilities, was determined by a fiber-optics catalytic probe (FOCP). Plasma was created in a flowing air within a quartz tube with the outer diameter of 5 cm by a 2.45 GHz microwave generator with the output power up to 1000 W. The flow of air was varied between 4 and 20 l/h. The O-atom density was found to increase monotonously with the increasing discharge power, and it decreased with the increasing flow rate. The degree of dissociation of oxygen molecules in the plasma column depended largely on the flow rate. At the air flow of 4 l/h it was about 80% but it decreased to about 20% at the flow of 20 l/h.  相似文献   
70.
汤颖  刘晔  路勇  朱萍  何鸣元 《催化学报》2007,28(4):321-326
采用共沉淀法,用不同金属盐为Cu源和Zn源合成了一系列CuZnAl水滑石,以此为前体经600℃焙烧后制得相应催化剂.用硝酸盐和醋酸盐合成的水滑石结晶度高,其衍生催化剂比表面积大、Cu的分散性好且易于还原;而用硫酸盐和盐酸盐合成的水滑石结晶度差,其衍生催化剂比表面积小、Cu的分散性差且不易还原.反应评价结果显示,用硝酸盐和醋酸盐制得的催化剂活性高、反应稳定性好;而用硫酸盐和盐酸盐制得的催化剂由于低的Cu表面积以及S和Cl的毒化作用而几乎无催化活性.在醋酸盐制备的催化剂上,产物干气中CO的浓度明显较低,在250℃和WHSV=3.28 h-1的条件下约为0.03%~0.04%,仅为硝酸盐所制催化剂上CO浓度的1/5;在210℃和WHSV=0.5 h-1的条件下,该催化剂上甲醇几乎完全转化,同时CO浓度降至约0.005%.N2O滴定、CO2程序升温脱附和程序升温还原结果显示,用醋酸盐和硝酸盐制备的催化剂具有极相近的Cu表面积和表面碱性,但前者CuO的还原峰温较后者低近70℃,归因于ZnO与CuO间的强相互作用,这是催化剂具有良好选择性的可能原因.  相似文献   
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