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991.
The paper is based on the method of determination of conjugated dienes in petroleum products by the combined method of chemical reaction with gas chromatography. 相似文献
992.
Min-Yu Lv Xiao-Min Hu Neng-Fei Gong Tie-Jun Wang Yu Guo Bi-Heng Liu Yun-Feng Huang Chuan-Feng Li Guang-Can Guo 《中国科学:物理学 力学 天文学(英文版)》2024,(3):5-10
Controlled quantum teleportation(CQT), which is regarded as the prelude and backbone for a genuine quantum internet, reveals the cooperation, supervision, and control relationship among the sender, receiver, and controller in the quantum network within the simplest unit. Compared with low-dimensional counterparts, high-dimensional CQT can exhibit larger information transmission capacity and higher superiority of the controller’s authority. In this article, we report a proof-of-principle experime... 相似文献
993.
Yonghui Zhang Huili Liang Fei Xing Qiqian Gao Yu Feng Yuping Sun Zengxia Mei 《中国科学:物理学 力学 天文学(英文版)》2024,(4):130-141
Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication, remote sensing, near-field imaging and military monitoring. Pursuing a high polarization ratio has always been the research hotspot in polarization-sensitive photodetectors. In this paper, we report a compression strain enhanced polarization ratio in β-gallium oxide(β-Ga2O3) single crystal flake. A rigorous crystallograph... 相似文献
994.
Yonghan Zhou Zhongfeng Ji Wenrui Cai Xuewei He Ruiying Bao Xuewei Fu Wei Yang Yu Wang 《Journal of Energy Chemistry》2024,(1):592-602
The development of a durable metallic coating on diverse substrates is both intriguing and challenging,particularly in the research of metal-conductive materials for applications such as batteries, soft electronics, and beyond. Herein, by learning from the pencil-writing process, a facile solid-ink rubbing technology(SIR-tech) is invented to address the above challenge. The solid-ink is exampled by rational combination of liquid metal and graphite particles. By harnessing the synergistic effects... 相似文献
995.
Yue-xin Yu Shou-fu Li 《计算数学(英文版)》2005,23(4):351-356
This paper is concerned with numerical stability of nonlinear systems of pantograph equations. Numerical methods based on (k, l)-algebraically stable Runge-Kutta methods are suggested. Global and asymptotic stability conditions for the presented methods are derived. 相似文献
996.
Room temperature phosphorescent(RTP) materials have a variety of applications ranging from bioimaging, optoelectronic devices to information security protection. However, the preparation procedures for these materials are always tedious and time-consuming. Here, we report a micro-wave approach to prepare RTP carbon dots(CDs) in only 8 min. The micro-wave promoted the carbon and boron bond formation using natural compounds glucose and boric acids. This result has been confirmed using TEM,FTIR, XP... 相似文献
997.
Decai Yang Yachao Xu Kai Pan Chuanxin Yu Jiaxing Wu Mingxia Li Fan Yang Yang Qu Wei Zhou 《中国化学快报》2022,33(1):378-384
Surface oxygen vacancy defects of mesoporous CeO2 nanosheets assembled microspheres(D-CeO2) are engineered by polymer precipitation, hydrothermal and surface hydrogenation strategies. The resultant D-CeO2 with a main pore diameter of 9.3 nm has a large specific surface area(~102.3 m2/g) and high thermal stability. The mesoporous nanosheets assembled microsphere structure prevents the nanosheets from aggregation, which is beneficial to effective mass tr... 相似文献
998.
LOSEV V F PANCHENKO Yu N DUDAREV V V IVANOV N G KONOVALOV I N PAVLINSKY A V PUCHIKIN A V 《中国光学》2011,4(1):1-8
研究了脉冲宽度为25~40 ns的放电脉冲XeCl准分子激光器的工作参数。结果显示,激光器产生的脉冲能量为0.2~0.7 J,重复频率为100 Hz,表明在泵浦功率为2.8~3.3 MW/cm3时,激光器实现了2.6%的激光效率和3.8%的本征效率。 相似文献
999.
研究了脉冲HF激光与水柱表面相互作用下电信号的产生过程。电信号显示了与激光能量线性相关的峰值间有时间间隔的两峰结构,且第二个尖峰在水柱底部的蒸汽腔塌缩后出现。实验还显示电信号的幅值和激光脉冲照射过程中是否存在膨胀和挤压的薄水层密切相关。如果在电池上边缘和石英平板(石英板紧邻电池,并与水柱上表面相接)之间存在一薄水层,电信号强度会增加10倍。 相似文献
1000.
Wenjuan Yan Dongpei Zhang Quanxing Zhang Yu Sun Shuxia Zhang Feng Du Xin Jin 《Journal of Energy Chemistry》2022,(1):583-606
Proton exchange membrane fuel cell and direct methanol fuel cells have gained more attention due to high-energy density,remarkable conversion efficiency,and low emission.However,their widely practical application was hindered by the high usage,limited sources,and high price of Pt catalysts.To achieve more cost-effective catalytic systems,PtCu-based multi-metallic nanoparticles are highly efficient for the oxygen reduction reaction(ORR)and methanol oxidation reaction(MOR).The incorporation of non-noble Cu metal can alter the properties of hybrids by forming new facets,planes,edges to promote the cleavage or formation of chemical bonds in catalytic reaction.This is a rapid growing area with numerous contributions from the interdisciplinary areas of nanocatalysis.This paper has summarized the recent progress in the past two years,in synthesizing PtCu-based alloys with various composition and morphologies,and critically discussed the effect of the catalyst preparation method,metal precursor,surfactant,reductant and heating temperature on nanostructure and electronic configuration.The important role of the composition,size,and morphology of PtCu bimetallic catalysts for electro oxidation reactions has been further established for structure-dependency studies.The challenges and perspectives of nanocatalysts for ORR and MOR discussed in this work is to provide further insights into rational design for cost-effective materials for energy. 相似文献