检索结果-南通市图书馆

Mechanism of Surface Modification for Sericite

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2007年第3期22卷 470-472页

作者：高惠民 School of Resources and Environmental Engineering Wuhan University of Technology

Surface modification of sericite by wet method was conducted with the addition of 1.0 % （w/w） silane. The resulting wetting contact angle and activity ratio of sericite were 130° and 98% respectively. Good pre-evaluation indexes of oil value （40.8%） and dispersivity （14.0 mL） were obtained. When 30 % of sericite was filled into acrylonitrile butadiene styrene（ABS） plastic, the bending strength and tensile strength of the composite material were reduced by 7% and 14.3% in comparison to those of pure ABS plastic, while the rigidity was increased by 3 times, and the impact strength and breaking elongation were reduced significantly. The mechanism of surface modification was investigated and the configuration of silane coupling agent on the surface of sericite was given. Infrared （IR） spectroscopic analysis indicates that the adsorption of silane on the surface of sericite belongs to chemical adsorption.

关键词： sericite surface modification ABS plastic

N-doped ordered mesoporous carbon as a multifunctional support of ultrafine Pt nanoparticles for hydrogenation of nitroarenes

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2017年第7期38卷 1252-1260页

作者：梁继芬张晓明景铃胭杨恒权山西大学分子科学研究所山西太原030006 山西大学化学化工学院山西太原030006

Due to the advantages of high surface areas, large pore volumes and pore sizes, abundant nitrogen content that favored the metal-support interactions, N-doped ordered mesoporous carbons are regarded as a kind of fascinating and potential support for the synthesis of effective supported cat-alysts. Here, a N-doped ordered mesoporous carbon with a high N content （9.58 wt%）, high surface area （417 m^2/g）, and three-dimensional cubic structure was synthesized successfully and used as an effective support for immobilizing Pt nanoparticles （NPs）. The positive effects of nitrogen on the metal particle size enabled ultrasmall Pt NPs （about 1.0 ± 0.5 nm） to be obtained. Moreover, most of the Pt NPs are homogeneously dispersed in the mesoporous channels. However, using the ordered mesoporous carbon without nitrogen as support, the particles were larger （4.4 ± 1.7 nm） and many Pt NPs were distributed on the external surface, demonstrating the important role of the nitrogen species. The obtained N-doped ordered mesoporous material supported catalyst showed excellent catalytic activity （conversion 100%） and selectivity （〉99%） in the hydrogenation of halogenated nitrobenzenes under mild conditions. These values are much higher than those achieved using a commercial Pt/C catalyst （conversion 89% and selectivity 90%）. This outstanding catalytic perfor-mance can be attributed to the synergetic effects of the mesoporous structure, N-functionalized support, and stabilized ultrasmall Pt NPs. Moreover, such supported catalyst also showed excellent catalytic performance in the hydrogenation of other halogenated nitrobenzenes and nitroarenes. In addition, the stability of the multifunctional catalyst was excellent and it could be reused more than 10 times without significant losses of activity and selectivity. Our results conclusively show that a N-doped carbon support enable the formation of ultrafine metal NPs and improve the reaction ac-tivity and selectivity.

关键词： N-doped mesoporous carbon Multifunctional support Ultrafine platinum nanoparticle Hydrogenation reaction Halogenated nitrobenzene

在线全文

学校读者我要写书评

暂无评论

输电线路山区覆冰故障分析与预防

山西电力 2015年第3期 57-59页

作者：荆凌燕李红军国网山西省电力公司运城供电公司山西运城044000

以山西运城山区线路发生的覆冰倒塔、导地线断裂等典型故障为例,通过对故障原因和气象条件的分析,提出了对事故杆塔的处理意见,以及针对运行线路检查、设计、和运行后应把握的原则。

关键词：输电线路覆冰外绝缘

在线全文

学校读者我要写书评

暂无评论

纤维基氧化还原电催化剂的研究进展

高等学校化学学报 2023年第5期44卷 316-336页

作者：李轩亓帅周伟良李小杰景玲胭冯超蒋兴星杨恒攀胡琪何传新深圳大学化学与环境工程学院深圳518071 中国科学技术大学化学物理系合肥230026

化石燃料的过度使用带来了严峻的环境污染问题,积极探索开发绿色可持续的能源转换和存储技术是目前研究的重要方向.以氢燃料和空气为动力的质子交换膜燃料电池和金属空气电池在众多能源技术中脱颖而出.但其工作过程中涉及的氧还原反应(O... 详细信息

化石燃料的过度使用带来了严峻的环境污染问题,积极探索开发绿色可持续的能源转换和存储技术是目前研究的重要方向.以氢燃料和空气为动力的质子交换膜燃料电池和金属空气电池在众多能源技术中脱颖而出.但其工作过程中涉及的氧还原反应(ORR)严重制约了清洁能源技术的广泛使用.纤维结构催化材料具有其比表面积高、几何结构可调及制备简单便捷等优势,在氧还原领域备受关注.本文综合评述了纤维结构催化材料金属活性中心的可控调节,介绍了纤维结构电催化材料在氧还原反应电催化方面的最新进展,揭示了纤维结构氧还原催化剂在电催化ORR反应中的构效关系,讨论了纤维结构电催化材料在ORR电催化中面临的挑战和机遇.

关键词：碳纳米纤维电催化氧还原反应金属中心

在线全文

学校读者我要写书评

暂无评论

短音骨导听性稳态反应中伪迹的研究

听力学及言语疾病杂志 2010年第3期18卷 243-245页

作者：刘辉莫玲燕陈静首都医科大学附属北京同仁医院耳鼻咽喉头颈科学教育部重点实验室(首都医科大学) 北京100730

目的研究短音骨导听性稳态反应中的伪迹问题。方法对21例(21耳)双耳极重度感音神经性聋患儿行骨导ASSR检测,刺激信号为0.5～4kHz倍频程的短音(tonepip),0.5kHz刺激信号上升、下降时间均为4ms;1、2、4kHz为2ms,0.5、1、2、4kHz刺激信号... 详细信息

目的研究短音骨导听性稳态反应中的伪迹问题。方法对21例(21耳)双耳极重度感音神经性聋患儿行骨导ASSR检测,刺激信号为0.5～4kHz倍频程的短音(tonepip),0.5kHz刺激信号上升、下降时间均为4ms;1、2、4kHz为2ms,0.5、1、2、4kHz刺激信号的刺激速率分别为77、85、93、101Hz。通过B-71骨振器给声,记录ASSR波形并观察是否出现伪迹,分析其原因。结果 1、4kHz出现伪迹的强度分别为115和100.5dB,0.5和2kHz分别在120.5和112dB(re:1μN)(以上强度约相当于听力级的60dBHL)未出现伪迹。结论骨导AS-SR的最大输出较气导小,且易出现伪迹,故骨导听力损失超过中度以上者,不宜行短音骨导听性稳态反应测试。

关键词：听性稳态反应骨导儿童

超细铂纳米颗粒复合多孔碳纳米纤维催化剂用于高效氧还原反应

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2023年第9期66卷 3509-3519页

作者：李轩李国栋邓晨景铃胭冯超孔艳蒋兴星周伟良柴晓燕杨恒攀胡琪何传新 Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518071China

合理设计铂纳米颗粒尺寸是制备高效氧还原电催化剂的关键.本工作中,我们借助静电纺丝和ZIF-8的双重限域作用合成了超细铂纳米颗粒锚定在多孔碳纳米纤维上的催化材料.低Pt负载(4.2 wt%)的Pt@PCNFs在碱性和酸性电解质中均表现出优异的氧... 详细信息

合理设计铂纳米颗粒尺寸是制备高效氧还原电催化剂的关键.本工作中,我们借助静电纺丝和ZIF-8的双重限域作用合成了超细铂纳米颗粒锚定在多孔碳纳米纤维上的催化材料.低Pt负载(4.2 wt%)的Pt@PCNFs在碱性和酸性电解质中均表现出优异的氧还原反应活性,其质量活性分别为41和51 A gPt^(-1),分别是商业Pt/C催化剂相应值的8倍和10倍.在不同温度的碱性和酸性环境的计时安培试验和加速稳定性实验中, Pt@PCNFs的稳定性均优于Pt/C基准.该催化剂的优异性能可归因于小尺寸的Pt纳米颗粒、丰富多孔的纤维结构、Pt纳米颗粒与N掺杂碳纳米纤维之间的强金属载体相互作用以及碳壳层的保护作用.

关键词：铂纳米颗粒氧还原反应多孔碳纳米纤维金属载体相互作用 Pt/C催化剂静电纺丝纤维结构催化材料

Sonogashira coupling reaction of homopropargyl ether with aryl bromides and synthesis of 2,5-disubstituted 3-bromofurans

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2009年第9期52卷 1314-1320页

作者： WANG Xin LIU lingyan CHANG WeiXing LI jing State Key Laboratory and Research Institute of Elemento-organic Chemistry Nankai UniversityTianjin 300071China

This paper presents Sonogashira coupling reaction of aryl bromides with protected homopropargyl alcohols such as tert-butyldimethyl(1-phenylbut-3-ynyloxy)silane and tert-butyldimethyl(1-(2,4-dichlorophenyl)but-3-ynyloxy)silane in piperidine catalyzed by PdCl2/PPh3 without copper(I). The coupling products, disubstituted acetylene, are obtained in good or excellent yields. These products can be further used for the synthesis of 2,5-disubstituted 3-bromofurans.

关键词： Sonogashira protected homopropargyl alcohol 2 5-disubstituted 3-bromofurans

Enrichment and toxic effects of triclosan on aquatic macrophytes Eichhornia crassipes and Hydrilla verticillata exposed to triclosan in sediments

在线全文

学校读者我要写书评

暂无评论

Ecological Processes 2023年第1期12卷 860-871页

作者： Xiuxiu Yan Fangyu Hu jing An Yongchao Yin lingyan Zhang Shuhe Wei Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China Department of Biology Northeastern UniversityBostonMA 02115USA

Background Clarifying the enrichment and response processes of triclosan(TCS)in hydrophytes is crucial for assessing the ecological risk of TCS in aquatic *** study delves into the chronic toxic effects of TCS in floating plant Eichhornia crassipes(Mart.)Solms and submerged plant Hydrilla verticillata(L.f.)Royle exposed to TCS sediments through hydroponic *** The absorption abilities of hydrophytes to TCS were *** concentration of TCS in the roots of *** was significantly higher than that in its leaves,while the absorption capacities of the leaves of *** to TCS were stronger than that in its ***,the physiological indexes,including chlorophyll concentration,soluble protein concentration,and antioxidant enzyme activities,showed a significant decrease with the exposure concentration and time of *** the chlorophyll and soluble protein concentrations and the antioxidant enzyme activities in the leaves were initially increased at a low concentration of TCS(at 7 days of exposure),they decreased significantly over *** to the leaves,the physiological indexes of the roots were more sensitive to the ecotoxicological effects of *** inhibition effects of TCS on *** were signifi-cantly higher than those on ***,which may be associated with the absorbing abilities of TCS and the growth characteristics of the ***’s correlation analysis found a significant negative correlation between the TCS concentrations and the antioxidant enzyme activities in the *** This study highlighted the differences in the uptake and enrichment process and toxic effects of TCS by different aquatic *** with ***,*** is more sensitive to TCS toxicity.

关键词： Triclosan Aquatic macrophyte Enrichment Antioxidant defense system Ecotoxicological effect

同方期刊数据库

缝纫式复位、囊膜拉钩固定联合囊袋张力环植入超声乳化治疗外伤性虹膜根部离断合并晶状体半脱位的效果

在线全文

学校读者我要写书评

暂无评论

温州医科大学学报 2023年第5期53卷 412-415,419页

作者：金玲艳张令洁段宏辉伍海建台州市眼科医院、台州市立医院眼科中心浙江台州318000

目的:探讨连续缝纫式复位、囊膜拉钩固定联合囊袋张力环(CTR)植入超声乳化治疗外伤性虹膜根部离断合并晶状体半脱位的效果。方法:对2016年1月至2020年6月台州市眼科医院收治的19例(19眼)外伤性虹膜根部离断和晶状体半脱位伴外伤性白内... 详细信息

目的:探讨连续缝纫式复位、囊膜拉钩固定联合囊袋张力环(CTR)植入超声乳化治疗外伤性虹膜根部离断合并晶状体半脱位的效果。方法:对2016年1月至2020年6月台州市眼科医院收治的19例(19眼)外伤性虹膜根部离断和晶状体半脱位伴外伤性白内障患者行内路连续缝纫式虹膜根部离断复位,联合临时性自制囊膜拉钩囊袋固定下的晶状体半脱位超声乳化及CTR和人工晶状体(IOL)植入。术后随访6个月,观察视力、眼压、虹膜根部复位、瞳孔形状和IOL位置情况。结果:19眼手术成功,术中无虹膜损伤及后囊膜破裂等并发症。术后所有术眼虹膜根部离断完全复位;瞳孔基本圆形15眼,近似圆形或竖椭圆形各2眼;IOL位置均良好。术后最佳矫正视力较术前明显提高,差异均有统计学意义(P0.05)。结论:连续缝纫式复位、囊膜拉钩固定联合CTR植入超声乳化治疗外伤性虹膜根部离断和晶状体半脱位,手术损伤小,提高了超声乳化手术的安全性。术后虹膜离断根部复位,IOL位正,视力恢复理想。

关键词：虹膜根部离断晶状体半脱位缝纫式复位超声乳化