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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： ren weiyi1,2, sun weiguo1, HOU Shilin3 & FENG Hao4 1. institute of physics, College of Chemical Engineering, sichuan university, chengdu 610065, china 2. institute of Theoretical physics, Xihua Normal university, Nanchong 637002, china 3. Department of physics, china Oceanography university, Qingdao 266003, china 4. College of physics, sichuan university, chengdu 610065, china 1. institute of physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. institute of Theoretical physics Xihua Normal University 637002 Nanchong China 3. Department of physics China Oceanography University 266003 Qingdao China 4. College of physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Rapid Energy Exchange between In Situ Formed Bromine Vacancies and CO_(2)Molecules Enhances CO_(2)Photoreduction

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Research 2024年第2期2023卷 763-771页

作者： Qin ren Ye He Hong Wang Yanjuan sun fan Dong Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China

Photocatalytic reduction of CO_(2)into fuels provides a prospective tactic for regulating the global carbon balance utilizing renewable solar ***,CO_(2)molecules are difficult to activate and reduce due to the thermodynamic stability and chemical *** this work,we develop a novel strategy to promote the adsorption and activation of CO_(2)molecules via the rapid energy exchange between the photoinduced Br vacancies and CO_(2)*** in situ continuous wave-electron paramagnetic resonance(cw-EPR)and pulsed EPR technologies,we observe that the spin-spin relaxation time(T_(2))of BiOBr is decreased by 198 ns during the CO_(2)photoreduction reaction,which is further confirmed by the broadened EPR *** result reveals that there is an energy exchange interaction between in situ formed Br vacancies and CO_(2)molecules,which promotes the formation of high-energy CO_(2)molecules to facilitate the subsequent reduction *** addition,theoretical calculations indicate that the bended CO_(2)adsorption configuration on the surface of BiOBr with Br vacancies caused the decrease of the lowest unoccupied molecular orbital of the CO_(2)molecule,which makes it easier for CO_(2)molecules to acquire electrons and get *** situ diffuse reflectance infrared Fourier transform spectroscopy further shows that the activated CO_(2)molecules are favorably converted to key intermediates of COOH*,resulting in a CO generation rate of 9.1μmol g^(-1)h^(-1)and a selectivity of 100%.This study elucidates the underlying mechanism of CO_(2)activation at active sites and deepens the understanding of CO_(2)photoreduction reaction.

关键词： reaction. adsorption activation

Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： sun Guang’ai1, CHEN Bo1, DU Honglin2, fan Zhijian1, GAO Tao3 & QI Xinhua31. institute of Nuclear physics and Chemistry, china Academy of Engineering physics, Mianyang 621900, china 2. Department of physics, Peking university, Beijing 100871, china 3. institute of Atomic and Molecular physics, sichuan university, chengdu 610065, china 1. institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. institute of Atomic and Molecular physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

Electronic structure and magnetism of R（Fe,Si）12 （R=Y,Nd）

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Science china(physics,Mechanics & Astronomy) 2006年第2期Mechanics & Astronomy) .卷 195-202页

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui fan Chang‑Qing Feng Rong Zhang Xiao‑Yang sun Qi An Hao‑fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan fan fan‑Zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑Yuan Luan Jie ren Zhi‑Zhou ren Xi‑Chao Ruan Zhao‑Hui Song Kang sun Zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng Wang Peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu Guo‑Hui Zhang Hang‑Chang Zhang Lin‑Hao Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou 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 Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China 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 North Night Vision Science and Technology(Nanjing)Research institute Co.Ltd Nanjing 211106China 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 Modern physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China china Academy of Engineering physics Institute of Nuclear Physics and ChemistryMianyang 621900China 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 china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

Endosulfan in Chinese air *** results

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Concurrent sampling of polychlorinated biphenyl(PCBs) in Chinese air and surface soil

持久性有机污染物论坛2008暨第三届持久性有机污染物全国学术研讨会

作者： Hongliang Jia~1 Yi-fan Li~(1,2*) Liyan Liu~3 Zhi Zhang~3 Bing sun~1 Nanqi ren~3 Xinnan Wan~4 Diandou Xu~5 Ed Sverko~(2,6)

(1 International Joint Research Center for Persistent Toxic Substances(IJRC-PTS),Dalian Maritime university,china;2 Science and Technology Branch,Environment Canada;3 IJRC-PTS,State Key Laboratory of Urban Water Resource and Environment,Harbin institute of Technology,china;4 RC-PTS, chengdu university of Technology,china;5 IJRC-PTS,institute of High Energy physics,Chinese Academy of Sciences,china;6 IJRC-PTS,McMaster university,Canada;* Corresponding author,

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Concurrent sampling of polychlorinated biphenyl(PCBs) in Chi...

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

持久性有机污染物论坛2008暨第三届持久性有机污染物全国学术研讨会

作者： Zhi Zhang~1 Liyan Liu~1 Yi-fan Li~(1,6*) Bing sun~2 Nanqi ren~1 Xinnan Wan~3 Diandou Xu~4 Tom Harner~6 Ed Sverko~(5,6) Jianmin Ma~6 (1 International Joint Research Center for Persistent Toxic Substances (IJRC-PTS),State Key Laboratory of Urban Water Resource and Environment,Harbin institute of Technology,china 2 IJRC-PTS,Dalian Maritime university,china 3 IJRC-PTS,chengdu university of Technology,china 4 IJRC-PTS,institute of High Energy physics,Chinese Academy of Sciences,china 5 IJRC-PTS,McMaster university,Canada 6 Science and Technology Branch,Environment Canada

*** International Joint Research Center for Persistent Toxic Substances(IJRC-PTS)started the Chinese persistent organic pollutants(POPs)Soil and Air Monitoring Program(SAMP)in 2005,which had run on a seasonal basis fo...

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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 Chemistry 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

Mn^(2+)掺杂对YAG∶Ce^(3+)荧光陶瓷发光性能的影响

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发光学报 2024年第5期45卷 762-771页

作者：喻彬孙炳恒付秀梅周世斌郝好莹沈方樑范金太姜本学张龙孙军南开大学物理科学学院天津300071 中国科学院上海光学精密机械研究所上海201800 成都东骏激光股份有限公司四川成都611630 中国科学院新疆理化技术研究所新疆乌鲁木齐830000

过渡族金属Mn^(2+)掺杂的石榴石荧光陶瓷被认为是实现高显色激光照明的候选材料。然而,由于Mn^(2+)在不同配位环境下离子半径的多样性,Mn^(2+)掺杂石榴石陶瓷体系设计方案尚不明确。本文采用真空烧结技术制备得到不同浓度Mn^(2+)掺杂的... 详细信息

过渡族金属Mn^(2+)掺杂的石榴石荧光陶瓷被认为是实现高显色激光照明的候选材料。然而,由于Mn^(2+)在不同配位环境下离子半径的多样性,Mn^(2+)掺杂石榴石陶瓷体系设计方案尚不明确。本文采用真空烧结技术制备得到不同浓度Mn^(2+)掺杂的YAG∶Ce^(3+)荧光陶瓷,并将Mn^(2+)分别设计进入八面体(OC)和十二面体(DO)格位。通过表征样品物相和显微结构、光致发光、荧光寿命、量子效率等,并通过LD激光器激发对荧光陶瓷的发光性能进行研究。实验结果表明,在添加电荷与体积补偿剂SiO_(2)的前提下,相比Mn^(2+)进入十二面体格位,Mn^(2+)进入八面体后石榴石的晶体结构更加稳定。因此,当Mn^(2+)的浓度控制在0.5%^(6)%(at)范围内,OC系列样品的量子效率高于DO系列样品。此外,OC系列样品的PL谱中位于588 nm和725 nm处的发射峰分别对应于Mn^(2+)占据八面体和十二面体格位的^(4)T_(1)→^(6)A_(1)电子跃迁,而DO系列样品中位于572 nm处的发射峰则源于Mn^(2+)占据扭曲的十二面体格位产生的电子跃迁。得益于Ce^(3+)→Mn^(2+)间高效的能量传递,将浓度为6%(at)的Mn^(2+)设计进入YAG∶Ce^(3+)中八面体格位制得荧光陶瓷,封装得到的激光白光光源的显色指数为70.8,相对色温为5117 K。本文对于Mn^(2+)掺杂的石榴石发光材料的开发研究是有力补充,也为提升YAG∶Ce^(3+)荧光陶瓷光谱中的红光成分,进而提高医疗、显示等领域的激光光源的显色性能提供借鉴。

关键词：荧光陶瓷 Ce^(3+)掺杂 Mn^(2+)掺杂格位

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