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determination of Double Beta Decay Half-Life of 136Xe with the PandaX-4T Natural Xenon Detector

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Research 2023年第2期2022卷 33-41页

作者： Lin Si Zhaokan Cheng Abdusalam Abdukerim Zihao Bo Wei Chen Xun Chen Yunhua Chen Chen Cheng Yunshan Cheng Xiangyi Cui Yingjie Fan Deqing Fang Changbo Fu Mengting Fu Lisheng Geng Karl Giboni Linhui Gu Xuyuan Guo Ke Han Changda He Jinrong He Di Huang Yanlin Huang Zhou Huang Ruquan Hou Xiangdong Ji Yonglin Ju Chenxiang Li Jiafu Li Mingchuan Li Shu Li Shuaijie Li Qing Lin Jianglai Liu Xiaoying Lu Lingyin Luo Yunyang Luo Wenbo Ma Yugang Ma Yujun Mao Yue Meng Nasir Shaheed Xiaofeng Shang Xuyang Ning Ningchun Qi Zhicheng Qian Xiangxiang Ren Changsong Shang Guofang Shen Wenliang Sun Andi Tan Yi Tao Anqing Wang Meng Wang Qiuhong Wang Shaobo Wang Siguang Wang Wei Wang Xiuli Wang Zhou Wang Yuehuan Wei Mengmeng Wu Weihao Wu Jingkai Xia Mengjiao Xiao Xiang Xiao Pengwei Xie Binbin Yan Xiyu Yan Yong Yang Chunxu Yu Jumin Yuan Ying Yuan Zhe Yuan Dan Zhang Minzhen Zhang Peng Zhang Shibo Zhang Shu Zhang Tao Zhang Li Zhao Qibin Zheng Jifang Zhou Ning Zhou Xiaopeng Zhou Yong Zhou IMOE Key Laboratory for Particle Astrophysics and Cosmology Shanghai Key Laboratory for Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Sichuan Research Institute Shanghai Jiao Tong UniversityChengdu 610213China Yalong River Hydropower Development Company Ltd.288 Shuanglin RoadChengdu 610051China School of Physics Sun Yat-sen UniversityGuangzhou 510275China Research Center for Particle Science and Technology Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao266237 ShandongChina Key Laboratory of Particle Physics and Particle Irradiation of Ministry of Education Shandong UniversityQingdao266237 ShandongChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China School of Physics Nankai UniversityTianjin 300071China Key Laboratory NuclearPyics and Ionampplication(MOE)Instituteof ModenPysics Fun Universty Shanghai 200433China School of Physics Peking UniversityBeijing 100871China Schol of Physics Beihang UniversityBejing 100191China International Research Center for Nuclei and Particles in the Cosmos Beijing key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 100191China School of Medical Instrument and Food Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Physics University of MarylandCollge ParkMaryland 20742USA School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratoryof Particle Detetion and Electronics University of Scienceand Technology of ChinaHefei230026China Department of Modern Physics University of Science and Technology of ChinaHefei230026China SJTU ParisElite Instute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

Precise measurement of two-neutrino double beta decay(DBD)half-life is an important step for the searches of Majorana neutrinos with neutrinoless double beta *** report the measurement of DBD half-life of 136xe using the Pandax-4T dual-phase Time Projection Chamber(TPC)with 3.7-tonne natural xenon and the first 94.9-day physics data release.

关键词： decay double determination

determination of Trace Copper with a Novel Kinetic Procedure/O_2 gallocyanine Indicator Reaction

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Rare Metals 1999年第4期18卷 294-298页

作者：何荣桓王建华邢红雁 Yantai Normal Univ Dept Chem Yantai 264025 Peoples R China Shandong Fishery Environm Monitoring Stn Yantai 264001 Peoples R China

A novel kinetic procedure for determination of trace copper was proposed based on the catalytic effect of Cu 2+ on the aerial oxidation of gallocyanine (GC), by which GC was oxidized and a colourless product was produced. The reaction was monitored spectrophotometrically in hexamethylene tetramine hydrochloric acid buffer solution. The calibration graph is linear for 0.05～0.5 μg/ml, and the detection limit is 0 02 μg/ml (Cu 2+ ). The selectivity for copper is satisfied as the interferences of Fe 3+ and Al 3+ could be easily and effectively eliminated by the addition of NH 4HF 2. The method was applied to the determination of copper in soil, tap water and simulated water samples, and the results were satisfactory.

关键词： Key Words: Kinetic spectrophotometry Copper determination

determination of trace elements in maifanite by outer cover electrode atomic emission spectrometry

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Rare Metals 2005年第2期24卷 161-165页

作者： LIJianqiang LUYiqiang JIANGWei SchoolofAppliedScience UniversityofScienceandTechnologyBeijingBeijing100083China

Maifanite is a nature medicinal stone used in many fields for long time. Theresearch on it showed that there are many trace elements in maifanite. In this paper, 36 traceelements in maifanite were determined by outer cover electrode atomic emission spectrometry, and thedetermination conditions were studied systematically. The results show that the concentrations ofelements, which are beneficial to human health, are higher, and the elements harmful to peoplehealth such as As, Cd, Hg, Cr, and Pb are tiny in maifanite. The precision and the accuracy werealso discussed.

关键词： atomic emission spectrometry outer cover electrode determination traceelements maifanite

determination of the Potential Barrier at the Metal／Oxide Interface in a Specular Spin Valve Structure with Nano—oxide Layers Using Electron Holography

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Chinese Physics Letters 2002年第10期19卷 1480-1482页

作者：王岩国沈峰等 BeijingLaboratoryofElectronMicroscopy InstituteofPhysicsandCenterforCondensedMatterPhysicsChineseAcademyofSciencesPoBox2724Beijing100080 BeijingLaboratoryofElectronMicroscopy InstituteofPhysicsandC

The local potential distribution in a specular spin valve structure with nano-oxide layers has been mapped by using off-axis electron holography in a field emission gun transmission electron microscope. A potential jump of 3-4 V across the metal/oxide interface was detected for the first time. The presence of the potential barrier confirms the formation of the metal/insulator/metal structure, which contributes to the increasing mean free path of spin-polarized electrons via the specular reflection of spin-polarized electrons at the metal/oxide interface. It leads to nearly double enhancement of the magnetoresistance ratio from 8% to 15%.

关键词： determination Potential Barrier Metal/Oxide Interface Specular Spin Valve Structure Nano-oxide Layers Electron Holography

determination of 23 β_2-agonists and 5 β-blockers in animal muscle by high performance liquid chromatography-linear ion trap mass spectrometry

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Science China Chemistry 2010年第4期53卷 832-840页

作者： WU YongNing1,2, MIAO Hong1, FAN Sai1,2 & ZHAO YunFeng1,2 1 Institute of Nutrition and Food Safety, Chinese Centre for Disease Control and Prevention, Beijing 100021, China 2 College of Veterinary Medicine, China Agricultural University, Beijing 100193, China 1. Institute of Nutrition and Food Safety Chinese Centre for Disease Control and Prevention Beijing 100021 China2. College of Veterinary Medicine China Agricultural University Beijing 100193 China

A high performance liquid chromatography-linear ion trap mass spectrometry method using isotope dilution technique has been developed for the simultaneous determination of 23 β2-agonists and 5 β-blockers in animal muscle tissues. Pork and chicken muscle samples were acid hydrolyzed and extracted with 5% trichloracetic acid in water, and then cleaned up using MCX solid phase extraction (SPE) cartridge. Methanol and 0.1% formic acid were used as mobile phases for gradient elution. A Waters AtlantisT3 column was used for separation. ESI positive ion scan mode was used with selective reaction monitoring. 9 β2-Agonists labeled by the deuterium isotope were used as internal standards for quantification. The linear ranges of 23 β2-agonists and 5 β-blockers were 5-200 μg/L, the coefficient of correlation was not less than 0.995, and the limit of detection for each compound in the muscle tissue was below 0.2 μg/kg. The recoveries of each compound in the spiked samples at three levels 5, 10, 20 μg/kg were in the range of 47.3%-123.7%, and the relative standard deviations were in the range of 3.2%-25.7%. The developed method is sensitive and specific for the determination of β2-agonists and β-blockers in pork and chicken muscle samples.

关键词： β2-agonists β-blockers muscle determination HPLC-ITMS

determination of boron concentration in uranium fuel samples by ICP-OES following a separation step by cation exchange resin

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Nuclear Science and Techniques 2018年第3期29卷 165-171页

作者： Yan Luo Hai-Xia Cong Rong-Rong Cui Chang-Qing Cao Wei Zhou Zhong-Qi Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences

The boron content of uranium fuel samples with boron concentrations in the range of 0.05–10 μg/g was determined using inductively coupled plasma optical emission spectrometry(ICP-OES) after the uranium was separated by cation exchange. The samples were dissolved in 3 M HNO_3 on a hot plate at 150℃ and evaporated to near dryness. The residues were redissolved in 0.2 M HNO-_3 and passed through a column loaded with Dowex 50WX8-400 resin. Uranium was adsorbed on the resin,while boron was easily eluted with 0.2 M HNO_3. The boron content of the effluent was determined using ICPOES. Several strategies were employed to improve the reliability of the experimentally determined boron *** addition of mannitol and proper control of the evaporation process were shown to be effective in preventing boron loss during sample dissolution and evaporation. The memory effect was eliminated by flushing the system with 1.5% ammonia for 30 s between successive sample runs,and the matrix match method was used to eliminate the matrix effect arising from mannitol during the ICP-OES analysis. The accuracy of the results of the analysis was determined by addition recovery tests and by comparison with the results of three Chinese certified reference materials(GBW04242, GBW04243, and GBW04232). Using the method we developed, the limit of detection for boron was as low as 0.05 μg/g in uranium fuel samples, and the relative standard deviations for 0.1–0.5 g uranium samples with 0.05–2 μg/g of boron were within 9%.

关键词： Boron determination ICP-OES Boron evaporation Memory effect Matrix match method Resin separation

determination of Copper by Flame Atomic Absorption Spectrometry after Preconcentration with Activated Carbon Impregnated with a New Schiff Base

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Chinese Journal of Chemistry 2005年第10期23卷 1437-1442页

作者： SABER TEHRANI, Mohammad RASTEGAR, Faramarz PARCHEHBAF, Ayob REZVANI, Zolfaghar Department of Chemistry Faculty of Science Science and Research Campus lslamic Azad University Tehran Iran Plate-Form Analitique lnorganique Lois Pasteur University Strasburg France Department of Chemistry Faculty of Science Azarbaijan Tarbiat Moallem University Tabriz Iran

A simple and reliable method for the extraction and determination of trace amounts of copper（Ⅱ） ions using activated carbon （AC） impregnated by a new Schiff base 5-[（4-heptyloxyphenyl）azo]-N-（4-propyloxyphenyl）-salicylaldimine （HPPS） and atomic absorption spectrometry is presented. Recovery efficiency and the influence of pH value, volume of sample solution, effect of different eluents, and interfering ions were evaluated. The limit of detection （3σ） was 2.62 ***^-1 and the relative standard deviation （n=10） was 1.5%. Under optimum conditions, the copper ions were concentrated 25 fold using 250 mL of sample solution and 10 mL of eluent. This procedure has been successfully applied to the determination of copper in different water samples.

关键词： preconcentration determination copper flame atomic absorption spectrometry activated carbon

determination of Hg^2＋ in Tap Water Based on the Electro- chemiluminescence of Ru（phen）3^2＋ and Thymine at Bare and Graphene Oxide-Modified Glassy Carbon Electrodes

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Chinese Journal of Chemistry 2016年第12期34卷 1297-1303页

作者： Yulong Gao Tao Wang Fengyu Liu State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian Liaoning 116024 China School of Chemistry Dalian University of Technology Dalian Liaoning 116024 China

The electrochemiluminescence （ECL） of the Ru（phen）3^2＋/thymine （T） system at bare and graphene oxide （GO）-modified glassy carbon （GC） electrodes was utilized to determine Hg2＋ in tap water. The ECL intensity of Ru（phen）3^2＋ was considerably enhanced by the addition of thymine because of the occurrence of ECL tion between them. Subsequently, the ECL intensity of Ru（phen）3^2＋/T system rapidly decreased with the addition of Ru（phen）3^2＋ because of the formation ofa T-Hg^2＋-T complex. A linear response （R2=0.9914） was obtained over a Hg^2＋ concentration range of 1.0×10 9 mol/L to 1.0×10^-5 mol/L with a detection limit of 3.4×10^-10 mol/L at a bare GC electrode in 0.1 mol/L phosphate buffer （pH=8.0）. The detection limit can be further reduced to 4.2 ×10^-12 mol/L after modification of the GC electrode by GO. To verify its applicability, the proposed method was utilized to determine Hg^2＋ in tap water and simulated wastewater. The method exhibited good reproducibility and stability and thus reveals the possibility of developing a novel ECL detection method for Hg^2＋.

关键词： electrochemiluminescence (ECL) determination 2+ Hg thymine graphene oxide

determination of hydroxyl radical in Fenton system

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Chinese Chemical Letters 2009年第10期20卷 1235-1240页

作者： Yan Fen Fang An Ping Deng Ying Ping Huang Alan G. MacDiarmid Research Institute for Renewable Energy China Three Gorges University Yichang 443002 China

Under visible light illumination, 2,3-diaminophenazine （DAPN） was generated from the oxidation of o-phenylenediamine （OPDA） in Fe^3＋/H2O2 solution. Hydroxyl radical （＊OH） produced in this system was determined by directly measuring the concentration of DAPN. In comparison with the traditional methods, the determination is more accurate and simple.

关键词： determination o-Phenylenediamine *OH Fenton