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971.
We demonstrated the interaction of a gold cone target with a femto second(fs) laser pulse above the relativistic intensity of 1.37×10 18 μm 2 W/cm 2.Relativistic electrons with energy above 2 MeV were observed.A 25%-40% increase of the electron temperature is achieved compared to the case when a plane gold target is used.The electron temperature increase results from the guiding of the laser beam at the tip and the intense quasistatic magnetic field in the cone geometry.The behavior of the relativistic electrons is verified in our 2D-PIC simulations. 相似文献
972.
构成主义观点致力于在自然主义的心灵图景中解释自我知识的特殊性与第一人称权威。为此,它主张高阶信念和一阶态度不是相互独立的,而是有着构成性的关系。概念论解释试图从认识主体的概念能力,特别是批判性推理的能力来作出论证。默认权威观点则诉诸日常话语实践的“语法”要求,主张认识主体对自我的态度拥有先天合理的、又可由证据挫败的确信。通过引入“以言行事”的思路,构成主义有希望确立起合理、审慎、有节制的第一人称权威观点。 相似文献
973.
Tian Bai Kongyin Zhao Zijie Lu Xuefang Liu Ze Lin Mengmeng Cheng Ziyi Li Dunwan Zhu Linhua Zhang 《中国化学快报》2021,32(3):1051-1054
Herein,copper ion doped calcium alginate(Cu~(2+)/CaAlg) composite hydrogel filtration membranes were prepared by using natural polymer sodium alginate(NaAlg) as raw material.The thermal stability and structure of the composite membranes were characterized by thermogravimetric analysis and infrared spectroscopy.The mechanical strength,anti-fouling performance,hydrophilicity and filtration performance of the membrane were studied.The results show that Cu~(2+)/CaAlg hydrogel membrane has excelle nt mechanical properties and thermal stability.The anti-swelling ability of the membrane was greatly enhanced by doping Cu~(2+).After three alternate filtration cycles,the flux recovery rate of Cu~(2+)/CaAlg hydrogel membrane can still reach 85%,indicating that the membrane has good antipollution performance.When the operation pressure was 0.1 MPa,the rejection of coomassie brilliant blue G250 reached 99.8% with a flux of 46.3 L m ~2 h ~1,while the Na_2 SO_4 rejection was less than 10.0%.The Cu~(2+)/CaAlg membrane was recycled after 24 h in the filtration process,and its flux and rejection rate did not decrease significantly,indicating that the hydrogel membrane has long-term application potential.The Cu~(2+)/CaAlg membrane has a wide range of applications prospect in dye desalination,fine separation and biopharmaceutical technology fields. 相似文献
974.
Man-Li Cao Jun-Ling Zhu Zhong-Lan Zhi Bao-Hui Ye Su-Yang Yao Xiu-Lian Zhang 《中国化学》2021,(6):1483-1490
Main observation and conclusion
Chiral-at-metal strategy was developed to resolve the essential sulfoxide pharmaceutical intermediates R-modafinil acid and its ... 相似文献
975.
Shengkai Li Zhaotian Zhu Xinqi Cai Minghui Song Shen Wang Qing Hao Long Chen Zhuo Chen 《中国化学》2021,(6):1491-1497
Main observation and conclusion
Surface-enhanced Raman spectroscopy(SERS)-based bioanalytical technique involves the interaction of SERS-active substrate with c... 相似文献
976.
PAN Chuanqi LIU Xiaoxuan ZHANG Xiang MAO Feihong XU Peiyan ZHU Yuhua DENG Hongtao LUO Zhu SUN Hongwei ZHANG Lizhi GUO Yanbing 《高等学校化学研究》2021,37(6):1341-1347
Copper oxide(CuO),due to its low cost,good chemical and physical stability,has recently been given special attention as a potential candidate for antibacterial agents.However,developing novel CuO nanocomposites with improved antibacterial property and unraveling the interface promotion mechanism has been a fundamental challenge for decades.Herein,well-defined CuO/graphdiyne(CuO/GDY)nanostructures with uniformly anchored CuO nanoparticles(ca.4.5 nm)have been fabricated.The CuO/GDY nanostructure exhibited superior E.coli inactivation efficiency,which is nearly 19 times and 7.9 times higher than the bare GDY and commercial CuO,respectively.The improved E.coli inactivation performance was mainly due to the increased reactive O2-species generated by the activation of molecular O2 over CuO/GDY surface.These findings demonstrate the efficient antibacterial activity of well-defined CuO/GDY nanostructures and provide insights on the development of efficient GDY-based antibacterial materials. 相似文献
977.
Zhaopeng Liu Youming Ni Tantan Sun Wenliang Zhu Zhongmin Liu 《Journal of Energy Chemistry》2021,(3):111-117
Direct converting carbon dioxide into hydrocarbon fuels and value-added chemicals would offer a very attractive approach for efficient utilization of CO2 as a carbon resource.Although,olefins,aromatics and gasoline have been successfully synthesized by CO2 hydrogenation,highly selective conversion of CO2 and H2 into C2+hydrocarbon is still challenging due to a high C-C coupling barrier and inhibiting the production of other long-chain hydrocarbons.Here,we report a composite catalyst made of InZrOx and SSZ-13 molecular sieve(InZrOx+SSZ-13),which exhibits 74.5% propane selectivity at 623 K.The 8-MR micropores and the higher strength of the acid for SSZ-13 benefit the formation of propane.Compared with pure InOx and m-ZrO2 the composite oxide InZrOx containing more oxygen vacancies,exhibits to be more readily reduced by H2 and easier to adsorb and desorb CO2 within the reaction temperature.All those could be beneficial to the activation and conversion of H2 and CO2.The catalytic performance of InZrOx+SSZ-13 in CO2 hydrogenation provides a potential for production of propane. 相似文献
978.
Wenmiao Chen Hongchang Jin Shuai Xie Huanyu Xie Junfa Zhu Hengxing Ji Li-Jun Wan 《Journal of Energy Chemistry》2021,(3):16-22
Lithium-sulfur(Li-S)batteries have become prospective candidates for next-generation energy storage owing to the high energy density and low cost.However,the sluggish kinetics of the electrochemical reaction and shuttle effect result in a rapid capacity decay.Herein,a titanium nitride nanocrystal/Ndoped graphene(TiN@NG)composite is developed to host elemental sulfur.The TiN nanoparticles decorated on graphene sheets attract Li polysulfides(LiPSx)and catalyze the electrochemical reduction and oxidation of LiPSx in the discharge and charge processes,respectively.These two effects effectively restrain the dissolution of the LiPSx and accelerate the electrochemical reactions,thereby,alleviating the shuttle effect.As a result,the cathode composed of TiN@NG/S delivers a remarkable reversible capacity(1390 mA h g-1 at 0.1 C)and excellent cycling performance(730 mA h g-1 after 300 cycles).We believe that this work can bring some inspiration for designing high-performance Li-S batteries. 相似文献
979.
980.
演示了一种基于单壁碳纳米管(SWCNTs)-聚合物自组装复合膜的光纤错位型氨气传感器。通过层层自组装技术在高Q谐振器上涂覆薄膜,薄膜上存在大量的游离羧基以及较大的比表面积,这提供了光与薄膜之间的强相互作用,以及对氨气的高吸附性和选择性。光谱随氨气浓度影响的有效折射率而变化。在(10~37) ×10−6的低浓度范围内,光谱变化与氨气浓度差之比即灵敏度为13.25 pm/10−6,检测极限为3.77 ×10−6并且具有良好的线性。这项工作研制为低浓度和高选择性氨气传感器提供了一种有效的方法。 相似文献