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131.
Direct aminations of allylic alcohols, benzylic alcohols, and benzhydrols with electron‐withdrawing (F, Br, I, NO2, or CN) substituents were efficiently catalyzed by aluminum triflate [Al(OTf)3] to afford the corresponding biarylamines in high yield, and the dibromo‐substituted product was further transformed into letrozole.  相似文献   
132.
综述了丙烯聚合物Z-N催化剂内给电子体的研究进展,讨论了内给电子体在丙烯聚合中的作用及机理.介绍了最新的内给电子体,通过对内给电子体在近年来发展的分析,对丙烯聚合物Z-N催化剂的发展进行了展望.  相似文献   
133.
We developed high-efficiency multi-photon emission (MPE) blue phosphorescent OLEDs with external quantum efficiency exceeding 40% at 100 cd m−2. In these MPE devices, we used a blue phosphorescent emitter, FIrpic and pyridine-containing electron-transporters, B3PyPB and B3PyMPM, B4PyMPM. We also used a well-known electron-transporter, BCP for comparison. We used a combination of TAPC/MoO3/Al/Liq layers as the charge-generation layer unit. An optimized MPE device showed an extremely high current efficiency of over 90 cd A−1 and a high power efficiency of over 40 lm W−1 at 100 cd m−2 without any outcoupling enhancement.  相似文献   
134.
A biomolecular interactive analysis with antibody-antigen and aptamer-protein was evaluated on Au-over layers deposited on the BioDVD surface. BioDVD consists of multilayered structures with Au layer on the top and it detects analytes by monitoring the changes in reflected light intensity due to analyte adsorption to the sensor surface, on which functional biomolecules are immobilized to bind specifically to the analytes. The BioDVD sensing instrument is based on a commercial digital versatile disc system, which allows the instrument to be small and inexpensive. The BioDVD platform can be fabricated utilizing mass production techniques with additional functional phase change layers that can serve both to enhance sensitivity by optimization of the interferometric cavity optical properties and also as a possible medium for the storage of test related information.  相似文献   
135.
介绍了检察院直接受理侦查案件由上一级检察院审查逮捕的法理依据,分析了职务犯罪案件决定逮捕权上提一级后将面临的问题,提出了克服问题的措施建议.  相似文献   
136.
制备出了以二醚为内给电子体的Ziegler-Natta(Z-N)催化剂及Z-N/茂金属(Z-M)复合催化剂。研究了催化剂类型(Z-N或Z-M)、休眠剂类型(苯乙烯(St)或对甲基苯乙烯(pMS))及用量对聚合过程、中间产品(均聚聚丙烯(PP))和最终产品(PP釜内合金)性能的影响,还利用扫描电子显微镜观测了PP釜内合金粒子的形貌。结果表明:St是比pMS更适宜的休眠剂;在保证使Z-M复合催化剂中茂金属组分充分休眠的前提下,应尽可能降低休眠剂的加入量;在St休眠剂存在下使用Z-M复合催化剂可制得23,-30℃抗冲击强度分别为47,5.6 kJ/m2的高刚高韧PP合金。  相似文献   
137.
Poly(arylene ether nitrile) (PEN) nanocomposites filled with functionalized graphite nanoplates (GNs) were prepared by a simple solution‐ casting method and then characterized by rheometer and thermogravimetric analysis (TGA). This study investigates how the surface treatment of GNs affects the GN dispersion state. The linear rheological test indicated that the 4‐aminophenoxyphthalonitrile‐grafted GN (GN‐CN) presented better dispersion in PEN matrix than purified GN because the corresponding composite showed the lower rheological percolation threshold, which was further confirmed by scanning electron microscopy and solution experiments. The TGA revealed that the presence of 4‐aminophenoxyphthalonitrile‐grafted GN retarded the depolymerization evidently compared with that of purified GN, showing remarkable increase in the temperatures corresponding to a weight loss of 5 wt % (increased by 21°C) and maximum rate of decomposition (increased by 9°C). Both the dispersion state and the surface functionalization of GN are very important to the thermal stability of PEN matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
138.
A new photochromic compound, S1 , containing a trans-cis photoisomerizable unit and a mercury detecting chemosensor unit, has been designed and synthesized. S1 displayed dramatic selectivity for mercury ions over other ions, through fluorescence intensity measurement. In addition, in the photostationary state, a colorimetric response to mercury ions was also achieved. The fluorescence turn-off of S1 by mercury ions was defined as the first check, while mercury-induced colorimetric variation in the photostationary state was set as the second check. Thus, a double-check mercury chemosensor can be achieved.  相似文献   
139.
We demonstrated the use of an asymmetrical donor–acceptor-type indoline dye—D131, developed for dye-sensitized solar cells, as an electron donor and fullerene C70 as an electron acceptor for thermal co-evaporated bulk-heterojunction organic solar cells (OSCs). In spite of the presence of intermolecular hydrogen bonds among D131 molecules, they can be thermally evaporated in high vacuum at a relatively low temperature of 220 °C. The blend ratio and thickness of the active layer of D131/C70 blend films in OSCs were optimized to achieve a maximum power-conversion efficiency of 4.5% with a short-circuit current of 9.1 mA cm?2, an open-circuit voltage of 0.89 V, and a fill factor of 0.56 under AM 1.5G solar illumination (100 mW cm?2), which is the best value reported so far for OSCs based on indoline-based donor materials.  相似文献   
140.
Silk is a protein fiber used to weave fabrics and as a biomaterial in medical applications. Recently, genetically modified silks have been produced from transgenic silkworms. In the present study, transgenic silkworms for the mass production of three colors of fluorescent silks, (green, red, and orange) are generated using a vector originating from the fibroin H chain gene and a classical breeding method. The suitability of the recombinant silks for making fabrics is investigated by harvesting large amounts of the cocoons, obtained from rearing over 20 thousand silkworms. The application of low temperature and a weakly alkaline solution for cooking and reeling enables the production of silk fiber without loss of color. The maximum strain tolerated and Young's modulus of the fluorescent silks are similar to those of ordinary silk, although the maximum stress value of the recombinant silk is slightly lower than that of the control. Fabrics with fluorescent color are demonstrated using the recombinant silk, with the color persisting for over two years. The results indicate that large amounts of genetically modified silk can be made by transgenic silkworms, and the silk is applicable as functional silk fiber for making fabrics and for use in medical applications.  相似文献   
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