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981.
Guobing Zhang Min Zhu Jinghua Guo Jingxuan Ma Xianghua Wang Hongbo Lu Longzhen Qiu 《Organic Electronics》2014,15(10):2608-2615
A series of benzodithiophene (BDT) and benzotrithiophene (BTT)-based conjugated polymers (P1–P4), with/without conjugated- and acyl-side chain, have been synthesized by Stille cross-coupling reaction. Their thermal, photophysical, electrochemical properties, devices performances, and microstructure have been investigated. Conjugated-side chain can significantly raise the thermal stability and acyl-side chain can lower HOMO/LUMO energy levels. Organic thin-film transistors (OTFTs) based on conjugated polymers were fabricated and the transistor electrical characterization showed the device performance was sensitive to the conjugated- and acyl-side chain substituent of polymers. A maximum hole mobility of 1.70 × 10−3 cm2 V−1 s−1 was obtained for P1-based devices, which is an order of magnitude higher than those of P3 and P4-based devices. The corresponding microstructures were investigated by grazing-incidence X-ray diffraction (GIXD) to correlate with conjugated- and acyl-side chain dependent carrier mobility of P1–P4. The results showed that the conjugated- and acyl-side chain have an impact on the polymer packing models and device performances. 相似文献
982.
The screening for yeasts incorporating exogenous eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) into their cellular lipids was conducted. Two percent of oil from fish scraps was added to a yeast isolation medium as a sole carbon source. From 143 soil samples, we isolated 23 yeast strains, nine of them were found to be capable of quickly assimilating the scrap fish oil. These nine strains, in addition to four previously isolated triglyceride-assimilating and lipase-producing strains, Yarrowia lipolytica and three Geotrichum species (FO274A, FO347-2 and FO401B), were cultured in a growth medium at 30 degrees C. Strains FO726A, FO765A and FO347-2 were selected on the basis of dry cell weight production and ability to store EPA and DHA in their cells, and their performance was further compared by varying cultivation temperature and time. From 1 g of the scrap fish oil, FO726A yielded 620 mg of dry cells, containing 47.1% lipid, 38.1% triglyceride, 3.3% EPA, and 4.9% DHA, when cultured at 25 degrees C for 36 h. Strain FO726A apparently has the highest ability to incorporate EPA and DHA into its cellular lipids. Results from further experiments showed that the incorporated EPA and DHA mainly existed in the form of triglyceride in the FO726A cell. These results suggest that FO726A is suitable for the production of cell mass rich in EPA and DHA for feed. 相似文献
983.
影响葡萄产量,品质的冠幕指标分析 总被引:1,自引:0,他引:1
对2 个酿酒品种,5 种整形方式的16 个冠幕指标分析,认为影响产量的主要指标是每株果穗数、穗重和每穗果粒数;影响含糖量的主要指标是叶果比和到达叶片的平均相对光强(即叶幕叶片平均受光状况);影响含酸量的主要指标是叶果比 相似文献
984.
利用响应面法优化乳酮糖制取工艺的研究 总被引:6,自引:0,他引:6
采用响应面分析法较系统地研究了碱性条件下乳糖异构化生产乳酮糖的工艺条件,得到了在一定条件变化范围内异构率随反应温度、时间、pH值的变化规律(回归方程)及相应的RSA等高图,可用于对异构率的预测及生产中工艺条件的优化。 相似文献
985.
烟草上马铃薯Y病毒的提纯与检测 总被引:4,自引:0,他引:4
本文是关于制备马铃薯Y病毒抗血清及ELISA检测技术的实验结果。采用垫层差速离心、蔗糖密度梯度离心提纯PVY,纯化的PVYOD260/OD280为1.56,将提纯的病毒制品免疫家兔,制备抗血清,经微量沉淀及环状沉淀试验,用提纯病毒测定抗血清的效价均为1/2048,并对制备的PVY—IgG作灵敏度及特异性测定。 相似文献
986.
Microstructure-properties relationship of transient liquid phase diffusion bonded a third generation single crystal superalloy joint 下载免费PDF全文
Microstructure of transient liquid phase( TLP) diffusion bonded a third generation single crystal superalloy joint was investigated using scanning electron microscopy( SEM),and mechanical properties test of joint was carried out,for obtaining relationship between microstructure and mechanical properties of joint. The results showed that the joint contained bonding zone and base metal. The diffusion zone was obviously observed. When it was not finished for isothermal solidification process,the bonding zone would contain isothermal solidification zone and rapid solidification zone. Metallographic examination revealed that isothermal solidification zone was consisted of γ and γ' phase. Rapid solidification zone was consisted of two different structures,which were ternary eutectic of borides,γ and γ' phase developing at the edge of joint,binary eutectic of γ and γ' phase appearing in the portion of joint. When it was not enough for homogenization process under the condition of finishing isothermal solidification process,the bonding zone would contain isothermal solidification zone and borides at the interface. Under the conditions of relatively high welding temperature and long welding time,average tensile strength of joint was equivalent to that of parent material. 相似文献
987.
988.
论述了效能评估的基本理论方法和模型,运用WSEIAC模型对舰舰导弹武器系统对海作战任务系统效能进行了描述,给出了模型参数的计算公式,并结合实例进行了计算分析. 相似文献
989.
战术导弹质心定位方法研究 总被引:2,自引:0,他引:2
从质心测量原理入手,提出了采用智能传感器技术的战术导弹质心定位系统的组成及技术指标.利用误差理论,对战术导弹质心定位系统进行了误差分析,消除了误差并提高了系统的测量精度. 相似文献
990.