The work of Chinese scientists conducted at the Joint Institute for Nuclear Research(JINR)(1956–1965)was inextricably linked to the Sino-Soviet relations in the 1950 s–1960 s.During the early stage of the JINR,with ...The work of Chinese scientists conducted at the Joint Institute for Nuclear Research(JINR)(1956–1965)was inextricably linked to the Sino-Soviet relations in the 1950 s–1960 s.During the early stage of the JINR,with the aid of advanced equipment and the international cooperation mechanism,Chinese scientists yielded significant results,such as the discovery of the antisigma-minus hyperon and the proof of the law of partial conservation of axial current(PCAC).After the Sino-Soviet split,Chinese scientists’activities at the institute were hampered by political tensions,eventually resulting in China’s withdrawal from the JINR in 1965.But through the involvement at the JINR,Chinese scientists were trained in scientific practices and participated in international exchange and cooperation which turned them into a new force in China’s nuclear industry,boosting its nuclear weapons,particle physics theory,and accelerator technology.In the meantime,the scientists’activities extended the international influence of the JINR.The withdrawal of China from the institute impacted both the JINR and the development of science in China.展开更多
This paper shows the development of solid oxide fuel cell (SOFC) technology at the Institute of Nuclear Energy Research. In the development, fabrication processes for planar anode-supported-cell (ASC) by conventio...This paper shows the development of solid oxide fuel cell (SOFC) technology at the Institute of Nuclear Energy Research. In the development, fabrication processes for planar anode-supported-cell (ASC) by conventional methods and metal-supported-cell (MSC) by atmospheric plasma spraying are well established. Procedures and techniques for stacking and cell/stack performance tests are continuously improved to enhance the quality and reliability. Innovative nano-structured catalysts, in which reduced Pt and CeOz particles dispersed onto the A120~ carriers can effectively prevent the migration and coalescence of the metal crystallites, are thermal stable and possess a conversion ratio higher than 95% for reforming of natural gas. A non-premixed after-burner/reformer is designed and fabricated, and it has passed the prerequisite functional tests. Layouts including stacks, components of BOP, power conditioning and control as well as gases and water supply, are designated for a 1-kW SOFC power system. In compliance with system requirements, operating modes, data acquisition, power conditioning, instrumentations, and control logics have been identified and settled. After successive system validation tests, two modules of 18-cell stacks are allocated into the SOFC system. Test results indicate a thermal self-sustaining system on natural gas is achieved with a power output of around 760 watts.展开更多
A reaction coupling system of transesterification and methoxycarbonylation with methyl phenyl carbonate (MPC) as intermediate was established to efficiently prepare 1,6-hexamethylene diurethane (HDU) from 1,6- bex...A reaction coupling system of transesterification and methoxycarbonylation with methyl phenyl carbonate (MPC) as intermediate was established to efficiently prepare 1,6-hexamethylene diurethane (HDU) from 1,6- bexametbylene diamine (HDA). The feasibility of the system was explored using the thermodynamics analysis, the reaction mechanism and the experiment results. The optimal reaction was carried out to get higher HDU yield. The thermodynamic analysis showed that the metboxycarbonylation of HDA with MPC, the Gibbs free energy of which was negative, was a spontaneous process. Furthermore, the equilibrium constant of the methoxycarbonylation of HDA with MPC was much greater than that of the transesterification of dimethyl carbonate (DMC) with phenol, so the reaction coupling could be realized under mild conditions. The reaction mechanism analysis indicated that phenoxy anion was the key spedes for reaction coupling. Higher MPC concentration was detected when sodium phenoxide was used as transesterification reactant with DMC, since the phenoxy anion of sodium phenoxide could be dissociated more easily. Sodium pbenoxide was more suitable to prepare HHDU through reaction coupling. A yield of HDU as high as 98.3% could be reached under the optimal conditions of mPhONa/mDMC = 0.027 and nDMC/nHDa = 8/1 at 90 ℃ in 2 h.展开更多
A LM-2D launch vehicle launched a quantum satellite along with a LX-1thin atmosphere research satellite and a Spanish small satellite from the Jiuquan Satellite Launch Center at 01:40 Beijing time on August 16.The wo...A LM-2D launch vehicle launched a quantum satellite along with a LX-1thin atmosphere research satellite and a Spanish small satellite from the Jiuquan Satellite Launch Center at 01:40 Beijing time on August 16.The world’s first quantum satellite is named Micius after a Chinese philosopher and scientist who lived 2,500 years ago.展开更多
The Shanxi Institute of Coal Chemistry,Chinese Academy of Sciences has designed and prepared a multiple confined-zone-based nickel hydrogenation catalyst by means of the atomic layer deposition(ALD)technology.In compa...The Shanxi Institute of Coal Chemistry,Chinese Academy of Sciences has designed and prepared a multiple confined-zone-based nickel hydrogenation catalyst by means of the atomic layer deposition(ALD)technology.In comparison with the non-confined-zone based catalyst,the multiple confined-zone-based nickel catalyst possesses an enhanced catalytic reactivity and catalytic stability for hydrogenation of cinnamaldehyde and nitrobenzene.展开更多
Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed a...Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.展开更多
At the time when Chinese scientists are hailing the successful launch of the DAMPE,a satellite to detect possible dark matter particles in space,and meanwhile expecting the launch of further space missions,we have the...At the time when Chinese scientists are hailing the successful launch of the DAMPE,a satellite to detect possible dark matter particles in space,and meanwhile expecting the launch of further space missions,we have the honor to invite Prof.Roger-Maurice Bonnet,former Science Director of ESA(the European Space Agency)to glve comments and advice on project management in the field of space science.展开更多
This article reviews my new optical fiber sensing (OFS) research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from...This article reviews my new optical fiber sensing (OFS) research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from UK in 1999. The research progress in long period fiber gratings (LPFGs), distributed fiber sensing systems and microfiber sensors is introduced. For LPFGs, the processing method with high-frequency CO2 laser pulses types of LPFGs fabricated and the related applications for both optical sensing and optical communication are described. For distributed fiber sensing systems, the fiber-optic polarization optical time domain reflectometer (POTDR), fiber-optic phase-sensitive optical time domain reflectometer (φ-OTDR) and Brillouin optical time-domain analyzer (BOTDA) are developed, respectively. For microfiber sensors, we mainly focus on the knot resonator and its application for sensing of the refractive index and acceleration, etc.展开更多
Understanding the heterogeneous catalytic properties of nanoparticles is of great significance for the development of high efficient nanocatalysts, but the intrinsic heterogeneities of nanocatalysts were always covere...Understanding the heterogeneous catalytic properties of nanoparticles is of great significance for the development of high efficient nanocatalysts, but the intrinsic heterogeneities of nanocatalysts were always covered in traditional ensemble studies. This issue can be overcome if one can follow the catalysis of individual nanoparticles in real time. This paper mainly summarizes recent developments in single- molecule nanocatalysis at single particle level in Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. These developments include the revealing of catalytic kinetics of different types (plane & edge) of surface atoms on individual Pd nanocubes, the observing of in situ deactivation of indi- vidual carbon-supported Pt nanoparticles during the electrocatalytic hydrogen-oxidation reaction, and the measurement of catalytic activation energies on single nanocatalysts for both product formation process and dissociation process, etc. These studies further indicate the advantages or unique abilities of single-molecule methods in the studies of nanocatalvsis or even chemical reactions.展开更多
基金supported in part by the Youth Innovation Promotion Association CAS(2018186)the National Science Foundation of China(NSFC)under Grant No.11775207。
文摘The work of Chinese scientists conducted at the Joint Institute for Nuclear Research(JINR)(1956–1965)was inextricably linked to the Sino-Soviet relations in the 1950 s–1960 s.During the early stage of the JINR,with the aid of advanced equipment and the international cooperation mechanism,Chinese scientists yielded significant results,such as the discovery of the antisigma-minus hyperon and the proof of the law of partial conservation of axial current(PCAC).After the Sino-Soviet split,Chinese scientists’activities at the institute were hampered by political tensions,eventually resulting in China’s withdrawal from the JINR in 1965.But through the involvement at the JINR,Chinese scientists were trained in scientific practices and participated in international exchange and cooperation which turned them into a new force in China’s nuclear industry,boosting its nuclear weapons,particle physics theory,and accelerator technology.In the meantime,the scientists’activities extended the international influence of the JINR.The withdrawal of China from the institute impacted both the JINR and the development of science in China.
文摘This paper shows the development of solid oxide fuel cell (SOFC) technology at the Institute of Nuclear Energy Research. In the development, fabrication processes for planar anode-supported-cell (ASC) by conventional methods and metal-supported-cell (MSC) by atmospheric plasma spraying are well established. Procedures and techniques for stacking and cell/stack performance tests are continuously improved to enhance the quality and reliability. Innovative nano-structured catalysts, in which reduced Pt and CeOz particles dispersed onto the A120~ carriers can effectively prevent the migration and coalescence of the metal crystallites, are thermal stable and possess a conversion ratio higher than 95% for reforming of natural gas. A non-premixed after-burner/reformer is designed and fabricated, and it has passed the prerequisite functional tests. Layouts including stacks, components of BOP, power conditioning and control as well as gases and water supply, are designated for a 1-kW SOFC power system. In compliance with system requirements, operating modes, data acquisition, power conditioning, instrumentations, and control logics have been identified and settled. After successive system validation tests, two modules of 18-cell stacks are allocated into the SOFC system. Test results indicate a thermal self-sustaining system on natural gas is achieved with a power output of around 760 watts.
基金Supported by the National Natural Science Foundation of China(21276126,21306089)the Jiangsu Province Higher Education Natural Science Foundation(09KJA530004,13KJB530006)
文摘A reaction coupling system of transesterification and methoxycarbonylation with methyl phenyl carbonate (MPC) as intermediate was established to efficiently prepare 1,6-hexamethylene diurethane (HDU) from 1,6- bexametbylene diamine (HDA). The feasibility of the system was explored using the thermodynamics analysis, the reaction mechanism and the experiment results. The optimal reaction was carried out to get higher HDU yield. The thermodynamic analysis showed that the metboxycarbonylation of HDA with MPC, the Gibbs free energy of which was negative, was a spontaneous process. Furthermore, the equilibrium constant of the methoxycarbonylation of HDA with MPC was much greater than that of the transesterification of dimethyl carbonate (DMC) with phenol, so the reaction coupling could be realized under mild conditions. The reaction mechanism analysis indicated that phenoxy anion was the key spedes for reaction coupling. Higher MPC concentration was detected when sodium phenoxide was used as transesterification reactant with DMC, since the phenoxy anion of sodium phenoxide could be dissociated more easily. Sodium pbenoxide was more suitable to prepare HHDU through reaction coupling. A yield of HDU as high as 98.3% could be reached under the optimal conditions of mPhONa/mDMC = 0.027 and nDMC/nHDa = 8/1 at 90 ℃ in 2 h.
文摘A LM-2D launch vehicle launched a quantum satellite along with a LX-1thin atmosphere research satellite and a Spanish small satellite from the Jiuquan Satellite Launch Center at 01:40 Beijing time on August 16.The world’s first quantum satellite is named Micius after a Chinese philosopher and scientist who lived 2,500 years ago.
文摘The Shanxi Institute of Coal Chemistry,Chinese Academy of Sciences has designed and prepared a multiple confined-zone-based nickel hydrogenation catalyst by means of the atomic layer deposition(ALD)technology.In comparison with the non-confined-zone based catalyst,the multiple confined-zone-based nickel catalyst possesses an enhanced catalytic reactivity and catalytic stability for hydrogenation of cinnamaldehyde and nitrobenzene.
文摘Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.
文摘At the time when Chinese scientists are hailing the successful launch of the DAMPE,a satellite to detect possible dark matter particles in space,and meanwhile expecting the launch of further space missions,we have the honor to invite Prof.Roger-Maurice Bonnet,former Science Director of ESA(the European Space Agency)to glve comments and advice on project management in the field of space science.
文摘This article reviews my new optical fiber sensing (OFS) research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from UK in 1999. The research progress in long period fiber gratings (LPFGs), distributed fiber sensing systems and microfiber sensors is introduced. For LPFGs, the processing method with high-frequency CO2 laser pulses types of LPFGs fabricated and the related applications for both optical sensing and optical communication are described. For distributed fiber sensing systems, the fiber-optic polarization optical time domain reflectometer (POTDR), fiber-optic phase-sensitive optical time domain reflectometer (φ-OTDR) and Brillouin optical time-domain analyzer (BOTDA) are developed, respectively. For microfiber sensors, we mainly focus on the knot resonator and its application for sensing of the refractive index and acceleration, etc.
基金supported by the National Basic Research Program of China(2014CB932700)the National Natural Science Foundation of China(21422307,21303180,21433003,21573215,21503212,and 21503211)+1 种基金‘‘the Recruitment Program of Global youth Experts”of China,Science and Technology Innovation Foundation of Jilin Province for Talents Cultivation(20160519005JH)Jilin Youth foundation(20160520137JH)
文摘Understanding the heterogeneous catalytic properties of nanoparticles is of great significance for the development of high efficient nanocatalysts, but the intrinsic heterogeneities of nanocatalysts were always covered in traditional ensemble studies. This issue can be overcome if one can follow the catalysis of individual nanoparticles in real time. This paper mainly summarizes recent developments in single- molecule nanocatalysis at single particle level in Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. These developments include the revealing of catalytic kinetics of different types (plane & edge) of surface atoms on individual Pd nanocubes, the observing of in situ deactivation of indi- vidual carbon-supported Pt nanoparticles during the electrocatalytic hydrogen-oxidation reaction, and the measurement of catalytic activation energies on single nanocatalysts for both product formation process and dissociation process, etc. These studies further indicate the advantages or unique abilities of single-molecule methods in the studies of nanocatalvsis or even chemical reactions.