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Science China chemistry 2009年第8期52卷 1216-1219页

作者： wang naixing1,2.& tang xinliang1,{2.,chinese academy of sciences,beijing 100080,China 2.College of chemistry and Chemical Engineering,Graduate University of chinese academy of sciences,beijing 100049,China 3 School of Chemical Engineering and Environment,beijing institute of Technology,beijing 100081,China technical institute of {2. and chemistry Chinese Academy of Sciences Beijing China College of chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China School of Chemical Engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Environment-adaptive phase-separation-porous fluorofilm for highperformance passive radiation cooling

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Nano Research 2024年第6期17卷 5636-5644页

作者： Weiming tang Yong Li Xue Meng Shutao wang Ziguang Zhao School of Future Technology University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Passive radiative cooling is widely recognized as an environmentally sustainable method for achieving significant cooling ***,the mechanical properties and environmental adaptability of current radiative cooling materials are not sufficient to maintain high cooling performance in external *** we reported an environment-adaptive phase-separation-porous fluorofilm for high-performance passive radiation *** to the homogenous fluoro-porous network with limited scattering efficiencies,we modulated the porous structure of the fluorofilm to achieve a strong emissivity of 95.2.(8-13μm)and a high reflectivity of 97.1%(0.3-2.5μm).The fluorofilm demonstrates a temperature drop of 10.5°C and an average cooling power of 81 W·m^(−2.under a sunlight power of 770 W·m^(−2..The high mechanical performance and environmental adaptability of fluorofilms are also *** its significant radiative cooling capability and robust environmental adaptability,the fluorofilm is expected to have a promising future in radiative temperature regulation.

关键词： fluorofilm passive radiation cooling porous optimization thermal regulation

Stereoselective C(sp^3)-C(sp^2. Negishi coupling of (2.amido-1-phenylpropyl)zinc compounds through the steric control of β-amido group

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Science China chemistry 2013年第9期56卷 1293-1300页

作者： tang Shi LI ShuHua ZHOU Dong ZENG HuiQiong wang {2. College of chemistry and Chemical Engineering Jishou University technical institute of {2. and chemistry Chinese Academy of Sciences

A controllable diastereoselective C(sp2.-C(sp3) Negishi coupling reaction of secondary benzylic zinc reagents with aryl bromides has been demonstrated for the first time, forming medicinally important 1-arylphenylethylamines. In the presence of Pd(OAc) 2.and S-phos, open-chain (2.amido-1-phenylethyl)zinc reagents bearing a -NHAc or NHCHO group underwent cross-coupling reaction to give syn 1-arylphenylethylamine as the major products, whereas the zinc reagents bearing a sterically hindered-NHCOC(CH3)2.OTBS group specifically yielded anti 1-arylphenylethylamines.

关键词： stereoselective Negishi coupling benzylic zinc 1-arylphenylethylamine aryl bromide

One-Pot Synthesis of Aliphatic Nitro Compounds by Michael/retro-Claisen Fragmentation Domino Reaction

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中国化学:英文版 2015年第4期33卷 401-404页

作者： Wei Zhang Yanjing wang Cuibing Bai Jialong Wen naixing wang technical institute of {2. and chemistry Chinese Academy of SciencesBeijing 100190China College of sciences Beijing University of Chemical TechnologyBeijing 100029China

A novel and concise method for the construction ofγ-nitro ketones and 1,3-dinitro compounds with chemo-selective acyl transfer has been presented under basic conditions via one-pot *** reactions feature high atom-and step-economic possess,mild condition and simple operation for one-pot synthesis of aliphatic nitro *** protocol provides the products in good *** possible reaction mechanism has also been proposed.

关键词： γ-nitro ketones 1 3-dinitro compounds chemoselective acyl transfer domino reaction atom-and step-economies

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液-气引射制冷系统实验研究

工程热物理学报 2018年第8期39卷 1643-1648页

作者：黄碧涵汤建波周远王俊杰季伟中国科学院低温工程学重点实验室(理化技术研究所) 北京100190 中国科学院大学北京100049

本文提出了一种以蒸发冷却为原理的液-气引射制冷系统。高密度流体如有机溶液以及无毒的室温液态金属可作为系统的驱动流体,引射真空实验结果显示液态金属引射器表现出卓越的真空性能;当引射器的引射性能显著提高后,对系统继续开展引射... 详细信息

本文提出了一种以蒸发冷却为原理的液-气引射制冷系统。高密度流体如有机溶液以及无毒的室温液态金属可作为系统的驱动流体,引射真空实验结果显示液态金属引射器表现出卓越的真空性能;当引射器的引射性能显著提高后,对系统继续开展引射制冷实验研究,分析讨论了三组制冷实验结果,其中采用异戊烷作制冷剂时,制冷效果最好,系统的制冷量和COP分别可达到35 W和0.60。

关键词：驱动流体液态金属真空性能引射制冷 COP

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基于双光斑的深度学习波前复原及校正

中国激光 2024年第13期51卷 24-33页

作者：许元斋唐秋艳王小军郭亚丁张林魏花彭钦军吕品中国科学院理化技术研究所北京100190 中国科学院大学北京100049 中国科学院软件研究所北京100191 中国科学院自动化研究所北京100190

探索了深度学习算法求解光强反演波前的非线性映射,实现了基于深度学习的波前探测(DLWFS)在自适应光学波前校正中的应用。采用聚焦和离焦双光斑反演波前,既简化了探测器结构,又减小了探测器体积。由于光强反演波前的过程在物理上不存在... 详细信息

探索了深度学习算法求解光强反演波前的非线性映射,实现了基于深度学习的波前探测(DLWFS)在自适应光学波前校正中的应用。采用聚焦和离焦双光斑反演波前,既简化了探测器结构,又减小了探测器体积。由于光强反演波前的过程在物理上不存在显式解,因此可以利用深度学习模型cGAN,通过类似图像处理的方式,建立光强-相位的非线性映射,将光斑的强度分布反演为波前分布,最终使波前校正系统配备较为紧凑的波前探测器。训练数据集通过物理衍射仿真获得,模型在测试集上的波前复原的最小残差RMS1531μm之间。在自适应光学波前校正实验中,将DLWFS作为自适应光学闭环校正过程中的波前探测器,验证了DLWFS的实用效果,光束质量因子从10.83校正至3.61。此外,还讨论了DLWFS的参数敏感性。

关键词：自适应光学波前复原深度学习光束质量

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5米光学02.应用在轨测试

遥感学报 2024年第3期28卷 591-600页

作者：唐新明肖晨超魏红艳刘宇韩波刘银年王军自然资源部国土卫星遥感应用中心北京100048 中国空间技术研究院遥感卫星总体部北京100094 中国科学院上海技术物理研究所上海200083 北京空间机电研究所北京100094

5米光学02.于2.2.年12.2.日成功发射,卫星与前序型号组成陆地中分业务卫星星座,建设形成天地一体化大幅宽定量化综合对地观测能力。在轨测试期间,自然资源部根据卫星设计指标要求,围绕土地资源、地质矿产、测绘地理信息、海洋海岛监... 详细信息

5米光学02.于2.2.年12.2.日成功发射,卫星与前序型号组成陆地中分业务卫星星座,建设形成天地一体化大幅宽定量化综合对地观测能力。在轨测试期间,自然资源部根据卫星设计指标要求,围绕土地资源、地质矿产、测绘地理信息、海洋海岛监测等领域业务,梳理共计32.业务测试项,并按照自然资源调查和监测的相关标准和技术规范,开展了应用测试评价工作。在轨测试表明,卫星系统、地面系统和应用系统各项功能正常、运行稳定,双星一致性好,具备组网运行条件,卫星数据质量可满足自然资源执法督察、地质矿产资源调查、生态修复工程跟踪评价、地理空间信息更新、围填海调查、海岸线变化监测、钢铁去产能等业务需求,高光谱和热红外载荷定量应用测试取得良好效果。本文在介绍该卫星的数据特点与应用能力的基础上,重点介绍和分析卫星在轨测试应用评价结果,可为后续业务化应用提供参考。

关键词：遥感 5米光学02. 自然资源卫星应用可见光/近红外高光谱热红外

Study of the response of 10B-doped MCP to wide-energy range neutrons from eV to MeV

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Nuclear Science and Techniques 2024年第8期35卷 132-141页

作者： Qiang Li Li‑Jiao wang Xiang‑Biao Qiu Jing‑Wen Li Wei Xu Tao Li Ze‑Bin Lin Chang‑Jun Ning Yong‑Hao Chen Rui‑Rui Fan Kang Sun Jing‑Yu tang Rong Zhang Han‑Tao Jing Bo Mei Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Zhen Chen Zeng‑Qi Cui An‑Chuan Fan Chang‑Qing Feng Fan‑Zhen Feng Ke‑Qing Gao Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei‑Hua Jia Hao‑Yu Jiang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Chao Li Gong Li Jia‑Wen Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Guang‑Yuan Luan Bin‑Bin Qi Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Zhi‑Xin Tan Sheng‑Da tang Peng‑Cheng wang Zhao‑Hui wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Li‑Kun Xie Yi‑Wei Yang Han Yi Yong‑Ji Yu Guo‑Hui Zhang Lin‑Hao Zhang Mo‑Han Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Mao‑Yuan Zhao Lu‑Ping Zhou Zhi‑Hao Zhou Ke‑Jun Zhu institute of High Energy physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China North Night Vision Science&Technology(Nanjing)Research institute Co.Ltd. Nanjing 211106China Sino‑French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China institute of Nuclear physics and {2. China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China USTC Archaeometry Lab University of Science and Technology of ChinaHefei 230026China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

Neutron-sensitive microchannel plates(nMCPs)have applications in neutron detection,including energy spectrum measurements,neutron-induced cross sections,and neutron imaging.10B-doped MCPs(B-MCPs)have attracted significant attention owing to their potential for exhibiting a high neutron detection efficiency over a large neutron energy *** spatial and temporal resolutions are useful for neutron energy-resolved ***,their practical applications still face many technical *** this study,a B-MCP with 10 mol%10B was tested for its response to wide-energy neutrons from eV to MeV at the Back-n white neutron source at the China Spallation Neutron *** neutron detection efficiency was calibrated at 1 eV,which is approximately 300 times that of an ordinary MCP and indicates the success of 10 B *** factors that caused the reduction in the detection efficiency were simulated and *** neutron energy spectrum obtained using B-MCP was compared with that obtained by other measurement methods,and showed very good consistency for neutron energies below tens of *** response is more complicated at higher neutron energy,at which point the elastic and nonelastic reactions of all nuclides of B-MCP gradually become *** is beneficial for the detection of neutrons,as it compensates for the detection efficiency of B-MCP for high-energy neutrons.

关键词： Neutron radiation image 10B-doped MCP Neutron response Wide-energy range neutrons

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理论是科学发展的关键

科技导报 2021年第19期39卷 104-108页

作者：王乃兴中国科学院理化技术研究所北京100190

理论思维是科学发展的关键。造纸术、指南针、火药、印刷术是中国古代四大发明,但从唐代到清代却无多少相关理论研究。列举了现代化学中一些精辟的理论例证,说明了理论的重要性。

关键词：科学方法理论思维科学实践

Measurement of the neutron total cross section of^(9)Be at the Back-n white neutron source of CSNS

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chinese physics C 2024年第8期48卷 140-152页

作者： Jiangbo Bai Jingyu tang Liqun Shi Yonghao Chen Han Yi Jie Bao Yu Bao Ping Cao Haolei Chen Zhen Chen Zengqi Cui Ruirui Fan Changqing Feng Keqing Gao Xiaolong Gao MinHao Gu Changcai Han Guozhu He Yongcheng He Yang Hong Yiwei Hu Hanxiong Huang Xiru Huang Haoyu Jiang Wei Jiang Zhijie Jiang Hantao Jing Ling Kang Bo Li Chao Li Jiawen Li Qiang Li Xiao Li Yang Li Jie Liu Shubin Liu Ze Long Guangyuan Luan Changjun Ning Mengchen Niu Binbin Qi Jie Ren Xichao Ruan Zhaohui Song Kang Sun Zhijia Sun Zhixin Tan Xinyi tang Binbin Tian Lijiao {2. Pengcheng {2. Zhaohui {2. Xiaoguang Wu Xuan Wu Likun Xie Xiaoyun Yang Li Yu Tao Yu Yongji Yu Guohui Zhang Linhao Zhang Qiwei Zhang Xianpeng Zhang Yuliang Zhang Zhiyong Zhang Luping Zhou Zhihao Zhou Kejun Zhu institute of Modern physics Fudan UniversityShanghai 200433China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Sate Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China institute of High Energy physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Department of Modern physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

The neutron total cross section data of^(9)Be are essential in the nuclear structure model research of light nuclei and nuclear power *** neutron total cross section of^(9)Be in the 0.3 eV−12. MeV energy region has been measured using time-of-flight and transmission methods with the Neutron Total Cross Sectional Spectrometer(NTOX)based on the multi-cell fast fission chamber at the China Spallation Neutron Source(CSNS)-Back-n white neutron source(Back-n).The fission count-neutron energy distributions of ^(2.5)U and ^(2.8)U without samples and with Be samples with three thicknesses were measured in the double-bunch operation mode for a beam power of 100 *** Bayesian method was used to eliminate the influence of the double-bunch problem on neutron measurement in the energy region above 10 *** neutron total cross section of^(9)Be results was consistent with ENDF/B-VIII.0 evaluation library data in the 0.3 eV−2. MeV energy *** the energy ranges of 0.3 eV to 10 keV and 0.01 to 2. MeV,the deviations between our results and the evaluation results of ENDF/B-VIII.0 were within 2.5%and 15%,*** the resonance energy region,the measured resonance energies in our experiment were 0.63,0.82.and 2.8 MeV,*** results showed that the total cross section uncertainties of three Be samples were within 2.2.in the energy region below 1 *** total cross section uncertainty of 30 mm Be from ^(2.5)U was the smallest and less than 5%in the energy region of 0.3 eV−12. *** results of this experiment can provide technical support for further data analysis and related nuclear data evaluation.

关键词： ^(9)Be neutron total cross section CSNS Back-n time-of-flight method transmission method multi-cell fast fission chamber