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Tuning the product selectivity of dimethyl oxalate hydrogenation over WO_(x) modified Cu/SiO_(2) catalysts

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Journal of energy Chemistry 2024年第10期97卷 128-138,I0004页

作者： zheng Li Zhuo Ma Yihui Li Ziang zhao Yuan Tan Ziyin Liu Xingkun Chen Nian Lei Huigang wang {3. Lu Hejun Zhu Yunjie Ding Hangzhou institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231ZhejiangChina Dalian National Laboratory for Clean energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese academy of sciences Beijing 100049China Shaanxi Key Laboratory of Clean energy Technology Utilization Yulin BranchDalian National Laboratory For Clean EnergyCASYulin 719199ShaanxiChina State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Product selectivity and reaction pathway are highly dependent on surface structure of heterogeneous *** vapor-phase hydrogenation of dimethyl oxalate(DMO),"EG route"(DMO→methyl glycolate(MG)ethylene glycol(EG)→ethanol(ET))and"MA route"(DMO→MG→methyl acetate(MA))were proposed over traditional Cu based catalysts and Mo-based or Fe-based catalysts,***,tunable yield of ET(93.7%)and MA(72.1%)were obtained through different reaction routes over WO_(x) modified Cu/SiO_(2) catalysts,and the corresponding reaction route was further proved by kinetic study and in-situ DRIFTS *** studies demonstrated that H_(2) activation ability,acid density and Cu-WO_(x) interaction on the catalysts were tuned by regulating the surface W density,which resulted in the different reaction pathway and product ***'s more,high yield of MA produced from DMO hydrogenation was firstly reported with the H_(2) pressure as low as 0.5 MPa.

关键词： Ethanol Dimethyl oxalate Selective hydrogenation Methyl acetate WCu/SiO_(2)catalyst

Single-atom-mediated electron islands boost photocatalytic CO_(2)chemical fixation

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Science china Chemistry 2024年第7期67卷 2292-2299页

作者： Shu Shang Lei Li Xin He Hui wang Lirong zheng wei Shao Xiaodong Zhang Yi Xie Hefei National Research Center for Physical sciences at the Microscale University of Science and Technology of ChinaHefei 230026China institute of energy Hefei Comprehensive National Science CenterHefei 230031China beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Chemistry and Chemical Engineering Hefei Normal UniversityHefei 230031China

Photocatalytic cycloadditions of CO_(2)with epoxides are emerging as a significant platform for the green synthesis of valuable carbonates,where efficient catalytic systems with spatially separated charge carriers are ***,a single p-block metal atom is proposed to be a candidate for photogenerated electron localization on a metal oxide *** taking the Bi single-atom supported on ZnO nanosheet(Bi1/ZnO)as an example,we show that the Bi atom plays the role of an electron island in the sea of delocalized holes within ***,the as-formed electron island could readily promote the rate-determining ring-opening process of cycloaddition *** from the unique spatially separated electrons and holes,the Bi1/ZnO achieves a high yield of cyclic carbonates with almost 100%*** study provides a pioneering strategy for enhancing the performances of photocatalytic CO_(2)chemical fixation.

关键词： electron islands CO_(2)photofixation photogenerated charge carriers

Hollow Multishelled Structure: Synthesis Chemistry and Application

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Chemical Research in Chinese Universities 2024年第3期40卷 346-393页

作者： MAO Dan wang Chao LI wei ZHOU Liang LIU Jian zheng Zjian {3. Yong CAO An-min wang Shutao HUANG Jiaxing HUO Fengwei CHEN Hongyu MAI Liqiang YU Ranbo wang Lianzhou LU Yunfeng YU Chengzhong YANG Qihua YANG Zhenzhong ZENG Hua Chun {3. Hujun TANG Zhiyong {3. Dongyuan wang Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChineseAcademy of SciencesBeijing 100190P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBejing 100190P.R.China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong SARP.R.China Department of Chemistry Fudan UniversityShanghai 200433P.R.China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070P.R.China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China School of Chemistry Beihang UniversityBejing 100191P.R.China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and beijing National Laboratory for Molecular sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190P.R.China School of Engineering Westlake UniversityHangzhou 310024P.R.China School of Flexible Electronics(Future Technologies) Nanjing Tech UniversityNanjing 211816P.R.China School of Science Westlake UniversityHangzhou 310024P.R.China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070P.R.China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083P.R.China School of Chemical Engineering and Australian institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072Australia College of Life Science and Technology Bejing University of Chemical TechnologyBejing 100029P.R.China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241P.R.China College of Life sciences Zhejiang Normal UniversityJinhua 321004P.R.China Department of Chemical Engineering Tsinghua UniversityBeijing 100

Hollow multishelled structure(HoMS),a promising and complex multifunctional structural system,features at least two shells that are separated by internal *** unique structure endows it with numerous advantages including low density,high loading capacity,large specific surface area,facilitated mass transport,and multiple spatial confinement *** the past twenty years,benefiting from the booming development of synthesis methods,various HoMS materials have been prepared and show promising applications in diverse areas.

关键词： Hollow multishelled structure Synthesis chemistry energy storage Catalysis Electromagnetic wave absorption Drug delivery Sensor

Atom-referenced and stabilized soliton microcomb

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Science china(physics,Mechanics & Astronomy) 2024年第2期67卷 2-8页

作者： Rui Niu Shuai Wan Tian-Peng Hua wei-Qiang wang zheng-Yu wang Jin Li Zhu-Bo wang Ming Li Zhen Shen Yu Robert Sun Shui-Ming Hu Brent ELittle Sai Tak Chu wei zhao Guang-Can Guo Chang-Ling Zou Yun-Feng Xiao Wen-Fu Zhang Chun-Hua Dong State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum physics University of Science and Technology of ChinaHefei 230026China University of Chinese academy of sciences Beijing 100049China Department of Chemical physics University of Science and Technology of ChinaHefei 230026China Department of physics and Materials Science City University of Hong KongHong Kong 999077China State Key Laboratory for Mesoscopic physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

For the applications of the frequency comb in microresonators,it is essential to obtain a fully frequency-stabilized microcomb laser *** this study,we present a system for generating a fully atom-referenced stabilized soliton *** pump light around 1560.48 nm is locked to an ultra-low-expansion(ULE)*** pump light is then frequency-doubled and referenced to the atomic transition *** repetition rate of the soliton microcomb is injection-locked to an atomic-clockstabilized radio frequency(RF)source,leading to mHz stabilization at 1 *** a result,all comb lines have been frequencystabilized based on the atomic reference and the ULE cavity,achieving a very high precision of approximately 18 Hz at 1 s,corresponding to the frequency stability of 9.5×10^(-14).Our approach provides a fully stabilized microcomb experiment scheme with no requirement of f-2f technique,which could be easily implemented and generalized to various photonic platforms,thus paving the way towards the ultraprecise optical sources for high precision spectroscopy.

关键词： microcavity frequency comb dissipative Kerr solitons fully stabilized microcomb

Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3.eV to 20 MeV on the Back-n at CSNS

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Nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： Jie-Ming Xue Song Feng Yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu Yi-wei Yang Zi-Jie Han Da-Jun zhao Hao-Qiang wang Bao-Qian Li Ji-Rong zhao Lei-Xun Tang Wen Luo Bo zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China institute of high energy {3. Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China institute of Nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3.eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the china Spallation Neutron *** energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick {3.-purity natural lead sample was employed for the neutron transmission *** on-beam background was determined using Co,In,Ag,and Cd *** excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling *** present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3.JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation *** agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding *** measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy *** provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline

The GECAM Real-time Burst Alert System

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Research in Astronomy and Astrophysics 2024年第10期24卷 36-47页

作者： Yue Huang Dongli Shi Xiaolu Zhang Xiang Ma Peng Zhang Shijie zheng Liming Song Xiaoyun zhao wei Chen Rui Qiao Xinying Song Jin {3. Ce Cai Shuo Xiao Yanqiu Zhang Shaolin Xiong Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Southwest Jiaotong University Chengdu 611756China Qufu Normal University Qufu 273165China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China College of physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China University of Chinese academy of sciences Chinese Academy of SciencesBeijing 100049China

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM),consisting of two microsatellites,is designed to detect gamma-ray bursts associated with gravitational-wave ***,we introduce the real-time burst alert system of GECAM,with the adoption of the BeiDou-3.short message communication *** present the post-trigger operations,the detailed ground-based analysis,and the performance of the *** the first year of the in-flight operation,GECAM was triggered by 42 gamma-ray *** GECAM real-time burst alert system has the ability to distribute the alert within~1 minute after being triggered,which enables timely follow-up observations.

关键词： (stars:)gamma-ray burst:general gravitational waves methods:data analysis

Detector performance of the Gamma-ray Transient Monitor onboard DRO-A satellite

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Science china(physics,Mechanics & Astronomy) 2024年第11期67卷 75-90页

作者： Pei-Yi Feng zheng-Hua An Da-Li Zhang Chen-wei wang Chao zheng Sheng Yang Shao-Lin Xiong Jia-Cong Liu Xin-Qiao Li Ke Gong Xiao-Jing Liu Min Gao Xiang-Yang Wen Ya-Qing Liu Xiao-Yun zhao Fan Zhang Xi-Lei Sun Hong Lu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese academy of sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.

关键词： NaI(Tl)detector energy response ground calibration gamma-ray detector DRO-A satellite

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao zheng Zi-An Zhou Tiao Feng Hui Li Cheng-Hua Sun Nüwang Yang Tian Yong zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese academy of sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(3. mm × 3. mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

In-flight energy Calibration of the GECAM Gamma-ray Detectors

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Research in Astronomy and Astrophysics 2024年第10期24卷 48-57页

作者： Rui Qiao Dong-Ya Guo Wen-Xi Peng Yan-Qiu Zhang Shuo Xiao Shao-Lin Xiong Chao zheng Chao-Yang Li Jia-Cong Liu wang-Chen Xue Jian-Jian He zheng-Hua An Da-Li Zhang Xin-Qiao Li Li-Ming Song Shi-Jie zheng Ke Gong Ya-Qing Liu Xin-Ying Song Xiao-Yun zhao Xiang-Yang Wen Yan-Bing Xu Xiang Ma Xiao-Bo Li Ping wang Yue Huang Ce Cai Qi-Bin Yi Yi zhao Chen-wei wang institute of high energy {3. Chinese Academy of SciencesBeijing 100049China University of Chinese academy of sciences Beijing 100049China china West Normal University Nanchong 637002China Xiangtan University Xiangtan 411105China beijing Normal University Beijing 100875China

The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)mission is designed to monitor the Gamma-Ray Bursts(GRBs)associated with gravitational waves and other high-energy transient *** mission consists of two microsatellites which are planned to operate at the opposite sides of the *** GECAM satellite could detect and localize GRBs in about 8 keV-5 MeV with its 25 Gamma-Ray Detectors(GRDs).In this work,we report the in-flight energy calibration of GRDs using the characteristic gamma-ray lines in the background spectra,and show their performance evolution during the commissioning ***,a preliminary cross-calibration of energy response with Fermi GBM data is also presented,validating the energy response of GRDs.

关键词： (stars:)gamma-ray burst:general instrumentation:detectors methods:data analysis