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991.
追忆江老师     
赵黎 《高分子通报》2014,(12):15-16
正2014年4月,我从加拿大回到北京。期间,我去黄庄,探望了黄美玉教授。门一开,黄老师站在那里,这么多年了,她基本上没变样,而且永远那样地和蔼可亲,当时她正在住院,因为江老师的骨灰安葬仪式,"获准"离开医院几个小时。黄老师坐到办公桌前,打开电脑,我紧紧挨着她,开始一张一张地浏览起这些年来她和江老师的照  相似文献   
992.
A simple and practical method for the synthesis of N-substituted-2-aminobenzothiazoles via a crosscoupling reaction of 2-iodo anilines with isothiocyanates is envisaged using nano copper oxide as a recyclable catalyst and Cs2CO3as a base in PEG-400,as a bio-degradable,reusable,inexpensive and nontoxic reaction medium,under ligand-free conditions.The present tandem process underlines environmental acceptability to access a wide range of N-substituted-2-aminobenzothiazoles in good to excellent yields.  相似文献   
993.
Ionic liquid gel polymers have widely been used as the electrolytes in all-solid-state supercapacitors, but they suffer from low ionic conductivity and poor electrochemical performance. Arc discharge is a fast, low-cost and scalable method to prepare multi-layered graphene nanosheets, and as-made graphene nanosheets (denoted as ad-GNSs) with few defects, high electrical conductivity and high thermal stability should be favorable conductive additive materials. Here, a novel ionic liquid gel polymer electrolyte based on an ionic liquid (EM1MNTF2) and an copolymer (P(VDF-HFP)) was modified by the addition of ad-GNSs as an ionic conducting promoter. This modified gel electrolyte shows excellent thermal stability up to 400 ℃ and a wide electrochemical window of 3 V. An all-solid-state supercapacitor based on commercial activated carbon was fabricated using this modified ionic liquid gel polymer electrolyte, which shows obviously improved electrochemical behaviors compared with those of the corresponding all-solid-state supercapacitor using pure ionic liquid gel polymer electrolyte. Specially, smaller internal resistance, higher specific capacitance, better rate performance and cycling stability are achieved. These results indicate that the ionic liquid gel polymers modified by ad-GNSs would be promising and suitable gel electrolytes for high performance all-solid-state electrochemical devices.  相似文献   
994.
纳米SiO2由于具有无味、无毒、无污染等特性,因而被广泛用作无机纳米填料。纳米SiO2极易团聚,从而限制了它的广泛应用。但纳米SiO2表面富含大量的硅羟基,可对其进行表面改性。纳米SiO2表面改性的方法较多,主要有表面物理改性和表面化学改性两种,其中表面化学改性中又以聚合物改性的效果最好。本文综述了国内外利用不同的聚合物——亲水性、疏水性和两亲性聚合物对纳米SiO2表面的化学改性,并对其应用进行了分析,展望了其发展前景。  相似文献   
995.
Assisted by graphene oxide(GO),nano-sized LiMn0.6Fe0.4PO4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn0.6Fe0.4PO4(S2)was about 80 nm in diameter.The discharge capacity of LiMn0.6Fe0.4PO4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn0.6Fe0.4PO4 and it in situ reduction of GO could improve the electrical conductivity of LiMn0.6Fe0.4PO4 material.  相似文献   
996.
正"沈宏柱化学名师工作室"由安徽省肥西县委人才办和肥西县教育局联合命名,由安徽省肥西中学的沈宏柱老师(安徽省特级教师)主持,于2010年4月挂牌成立,学员是来自肥西县三河中学、官亭中学和肥西中学等校的化学教师。该工作室主要开展的工作如下:1制订总体工作方案,分期计划实施  相似文献   
997.
高三化学复习面临周课时数减少、课后不允许布置作业、复习内容多等实际情况,提出"微型专题化"的复习思路来应对江苏化学高考。  相似文献   
998.
Nanostructured -y-A12O3 with high surface area and mesoporous structure was synthesized by sol-gel method and employed as catalyst support for nickel catalysts in methane reforming with carbon dioxide. The prepared samples were characterized by XRD, N2 adsorption-desorption, TPR, TPO, TPH, NH3-TPD and SEM techniques. The BET analysis showed a high surface area of 204 m2.g-1 and a narrow pore-size distribution centered at a diameter of 5.5 nm for catalyst support. The BET results revealed that addition of lanthanum oxide to aluminum oxide decreased the specific surface area. In addition, TPR results showed that addition of lanthanum oxide increased the reducibility of nickel catalyst. The catalytic evaluation results showed an increase in methane conversion with increasing lanthanum oxide to 3 mol% and further increase in lanthanum content decreased the catalytic activity. TPO analysis revealed that the coke deposition decreased with increasing lanthanum oxide to 3 mol%. SEM and TPH analyses confirmed the formation of whisker type carbon over the spent catalysts. Addition of steam and Oxide to drv reformin feed increased the methane conversion and led to carbon free ooeration in combined orocesses.  相似文献   
999.
A series of high surface area graphitic carbon materials (HSGCs) were prepared by ball-milling method. Effect of the graphitic degree of HSGCs on the catalytic performance of Ba-Ru-K/HSGC-x (x is the ball-milling time in hour) catalysts was studied using ammonia synthesis as a probe reaction. The graphitic degree and pore structure of HSGC-x supports could be successfully tuned via the variation of ball-milling time. Ru nanoparticles of different Ba-Ru-K/HSGC-x catalysts are homogeneously distributed on the supports with the particle sizes ranging from 1.6 to 2.0 nm. The graphitic degree of the support is closely related to its facile electron transfer capability and so plays an important role in improving the intrinsic catalytic performance of Ba-Ru-K/HSGC-x catalyst.  相似文献   
1000.
In the present work,an interconnected sandwich carbon/Si-SiO2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition(TVD).The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode,but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode.The resulting material delivered a reversible capacity of 1094 mAh/g,and exhibited excellent cycling stability.It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.  相似文献   
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