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Design study of charge-stripping scheme of heavy ion beams for HIAF-BRing

Nuclear Science and Techniques 2024年第5期35卷 30-41页

作者： Jun-Jie Zhang Zhi-You xu jin-Quan Zhang wen-wen Ge Liang-Ting Sun Huan-Yu Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Charge strippers play an essential role in heavy-ion accelerators by stripping the projectile ions to higher charge states to enhance the acceleration efficiency downstream of the *** the high-energy mode of the booster ring(BRing)of the high-intensity heavy-ion accelerator facility,the pre-accelerated ions from the iLinac will be stripped by a carbon foil to higher charge states and then injected into the *** key parameters of the stripper and stripped ions were calculated,and the influence of stripping on the beam quality was *** get high stripping efficiencies,the foil thicknesses and resultant charge state distributions for the typical ions were determined by the code *** equilibrium thickness was obtained for the U beam,while the stripper thicknesses for the Xe and Kr beams were determined based on a compromise between the stripped charge states and the stripping *** energy loss,energy straggling,and emittance growth due to stripping have a non-negligible impact on the transport of the stripped beams and the injection of the ***,these parameters were simulated by *** addition,the foil’s temperature evolution,which greatly affects the foil lifetime,was simulated by *** maximum temperature of the foil bombarded by the U and Xe beams with the nominal parameters will exceed the safe value in terms of the impact of evaporation on the foil’s *** the foil temperature constraint,the highest tolerable beam intensity and the injected ion number into the ring were derived for different beam *** results of this paper will present important reference data for the optimization design and commissioning of the beamline and injection to the BRing for the stripped ions.

关键词： High-intensity heavy-ion accelerator facility Charge stripper Energy spread Thermal analysis Emittance growth Injection turns

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Formation of Na_(1+x)V_3O_8 Nanoribbon Thin Film from V_2O_5 Xerogel on Sodium Silicate Glass Substrate

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Chemical Research in Chinese Universities 2007年第4期23卷 381-383页

作者： GUO Yi xu jin-jie LI Jun YANG wen-sheng College of Chemistry Jilin University Changchun 130012 P. R. China

Na1＋xV3O8 nanoribbon thin film was successfully fabricated by annealing the V2O5 xerogel film on sodium sili-cate glass substrate at 450℃. It has been identified that the amount of sodium ions diffused into the V2O5 xerogel film increases with the high temperature of annealing treatment. The sodium glass substrate serves as a limited sodium source to induce the transformation from V2O5 to Na1＋xV3O8.

关键词： Vanadium pentoxide Sodium silicate glass Nanoribbon Cathode materials

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Photopolymerization of Dendritic Acrylated Aromatic/Aliphatic Polyesters and Properties of Their Cured Films

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Chemical Research in Chinese Universities 2002年第3期18卷 354-357页

作者： xu Gang LIANG Hong-bo SHI wen-fang BAO jin-wen State Key Laboratory of Fire Science and Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026China Institute of Aeronautical Materials Beijing 100095

The radiative curable dendritic acrylated aromatic/aliphatic polyesters based on pentaerythritol, 1,2,4 benzenetricaboxylic anhydride and epoxy propane modified with acryloyl chloride were synthesized via a divergent procedure, and their photopolymerization kinetics was studied by photo differential scanning calorimetry. The mechanical properties and the morphology of the fracture surface of the cured dendritic polyester films were investigated by means of dynamic mechanical thermal analysis and scanning electron microscopy, respectively.

关键词： Dendritic polyester Radiation curing Photopolymerization kinetics Thermal mechanical property

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Can pediatric vasovagal syncope be individually managed?

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World Journal of Pediatrics 2022年第1期18卷 4-6页

作者： wen-Rui xu Jun-Bao Du Hong-Fang jin Department of Pediatrics Peking University First HospitalNo.1Xi’an-Men StreetWest DistrictBeijing 100034China Key Lab of Molecular Cardiovascular Sciences Ministry of EducationBeijingChina

In children and adolescents,syncope is common and accounts for a considerable proportion of emergency *** underlying diseases of pediatric syncope mainly include neurally mediated syncope(NMS)and cardiogenic *** accounts for 70–80%of pediatric syncopal cases,and one of the most common forms is vasovagal syncope(VVS)[1–3].In children with VVS,owing to the impairment of the barorefex integrity,the sympathetic system usually becomes overexcited after the change in position,leading to forceful contractions of a relatively empty ventricle and fnally causing a sympathetic withdrawal and an increased vagal activity.A relatively insufcient central volume,excessive vasodilation of peripheral vessel,autonomic nervous dysfunction,and neurohormonal disturbance may be aggravating ***,the efectiveness of previously unselected treatments for VVS has not been *** such,a comprehensive assessment of the clinical characteristics,pathogenesis,and biochemical markers is needed to select the corresponding *** individualized treatment for VVS was proposed,several improvements have been made in the feld.

关键词： syncope pediatric treatment

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Modulation of red-light emission from carbon quantum dots in acid-based environment and the detection of chromium(Ⅲ)ions

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Journal of Materials Science & Technology 2021年第24期83卷 58-65页

作者： Ju Tang jin Zhang Weizuo Zhang Yiming Xiao Yanli Shi Fanquan Kong wen xu School of Physics and Astronomy and Key Laboratory of Quantum Information of Yunnan Province Yunnan UniversityKunming650091China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei230031China

ⅢIn this study,the carbon quantum dots,which can emit sharp red light(R-CQDs)under optical excitation,were synthesized via simple heat treatment of wine *** features of the photoluminescence(PL)emission from R-CQDs in solutions with different p H values and with metal ions were *** intensity of the PL emission from R-CQDs depends sensitively on the p H values of the solutions with the ***,the p H-response of the PL intensity is reversible and can be enhanced linearly in the p H value range from 4 to 12,indicating that the R-CQDs can be applied for the p H ***,the quench of the PL emission from R-CQDs can be observed when adding chromium(Ⅲ)ions into the solution with *** effect can be utilized for selective and quick detection of chromium(Ⅲ)ions in solutions simply via the standard PL *** interesting and important findings from this work can be applied to explore more practical applications of the CQDs prepared cheaply and easily.

关键词： Red emitting carbon quantum dots Photoluminescence pH sensor Chromium(Ⅲ)ion detection

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采用MRI T_2~*值定量评估腰椎骨质疏松的价值

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河北医科大学学报 2019年第5期40卷 575-578,591页

作者：张晓飞吴慧钊韩殊曼曹磊闻锦旭吴文娟河北医科大学第三医院放射科河北石家庄050051

目的探讨采用MRI T_2~*值定量评估腰椎骨质疏松的临床应用价值。方法对87例绝经后老年女性进行腰椎常规(T_1WI及T_2WI)序列、T_2~*mapping序列扫描及定量CT骨密度(bone mineral density,BMD)检查,分别测量L_2～L_4椎体的T_2~*值及L_2～... 详细信息

目的探讨采用MRI T_2~*值定量评估腰椎骨质疏松的临床应用价值。方法对87例绝经后老年女性进行腰椎常规(T_1WI及T_2WI)序列、T_2~*mapping序列扫描及定量CT骨密度(bone mineral density,BMD)检查,分别测量L_2～L_4椎体的T_2~*值及L_2～L_4椎体的BMD值。以BMD值为金标准,将检测椎体分入骨质疏松、骨量减少、骨量正常3组中,对测量的T_2~*值及BMD值进行Spearman相关性分析,使用受试者工作特征(receiver operating characteristic curve,ROC)曲线分析T_2~*值诊断腰椎骨质疏松和骨量减少的敏感度、特异度等。结果骨量正常、骨量减少、骨质疏松3组T_2~*值与BMD值均呈负相关(r_s=-0.47、-0.52、-0.57,P<0.05)。ROC曲线显示T_2~*值诊断腰椎椎体骨量减少及骨质疏松的ROC曲线下面积分别为0.76、0.79,取截断值12.48时其诊断骨量减少的敏感度为82.2%、特异度为59.3%,取截断值17.13时其诊断骨质疏松的敏感度为87.1%、特异度为56.2%。结论 MRI T_2~*mapping序列可无创性定量反映腰椎椎体骨质密度并对骨质疏松程度作出评价,具有临床应用价值。

关键词：骨质疏松,绝经后骨密度诊断显像

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利用原子在圆偏振激光场中的强场电离产生自旋极化电子

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原子与分子物理学报 2025年第3期42卷 101-109页

作者：王中元高轩鸿景文泉杜进旭赵松峰西北师范大学物理与电子工程学院兰州730070

圆偏振激光场中原子的非绝热强场电离为产生自旋极化电子提供了机会.我们应用这些解析电离速率公式[Ingo Barth and Olga Smirnova,***.A 88,013401(2013)]更系统地研究了通过Kr和Xe原子在右旋圆偏振激光脉冲中的强场电离产生自旋极化电... 详细信息

圆偏振激光场中原子的非绝热强场电离为产生自旋极化电子提供了机会.我们应用这些解析电离速率公式[Ingo Barth and Olga Smirnova,***.A 88,013401(2013)]更系统地研究了通过Kr和Xe原子在右旋圆偏振激光脉冲中的强场电离产生自旋极化电子,并证实了不同自旋态的光电子能量分布有很大差异、电子的自旋极化敏感地依赖于光电子能量.另外,在光电子能谱的低能部分其自旋极化可以达到100%,并且通过调节激光强度和频率可以很好地控制能量积分的自旋极化.

关键词：自旋极化电子非绝热强场电离右旋圆偏振激光场

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Novel infrared differential optical absorption spectroscopy remote sensing system to measure carbon dioxide emission

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Chinese Physics B 2019年第1期28卷 353-359页

作者： Ru-wen Wang Pin-Hua Xie jin xu Ang Li Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Science and Technology of China CAS Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

A CO_2 infrared remote sensing system based on the algorithm of weighting function modified differential optical absorption spectroscopy(WFM-DOAS) is developed for measuring CO_2 emissions from pollution sources. The system is composed of a spectrometer with band from 900 nm to 1700 nm, a telescope with a field of view of 1.12?, a silica optical fiber, an automatic position adjuster, and the data acquisition and processing module. The performance is discussed,including the electronic noise of the charge-coupled device(CCD), the spectral shift, and detection limits. The resolution of the spectrometer is 0.4 nm, the detection limit is 8.5 × 10^(20)molecules·cm^(-2), and the relative retrieval error is < 1.5%.On May 26, 2018, a field experiment was performed to measure CO_2 emissions from the Feng-tai power plant, and a twodimensional distribution of CO_2 from the plume was obtained. The retrieved differential slant column densities(dSCDs)of CO_2 are around 2 × 10^(21) molecules·cm^(-2) in the unpolluted areas, 5.5 × 10^(21)molecules·cm^(-2) in the plume locations most strongly affected by local CO_2 emissions, and the fitting error is less than 2 × 10^(20)molecules·cm^(-2), which proves that the infrared remote sensing system has the characteristics of fast response and high precision, suitable for measuring CO_2 emission from the sources.

关键词： weighting function modified differential optical absorption spectroscopy(WFM-DOAS) infrared instrument CO2 emission sources

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The application of China’s land observation satellites within the framework of Digital Earth and its key technologies

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International Journal of Digital Earth 2012年第3期5卷 189-201页

作者： wen xu China Centre for Resources Satellite Data and Application Haidian DistrictBeijingChina

Digital Earth is an interdisciplinary field involving space technology,information technology,and *** article introduces the land observation satellite system of China and discusses the requirements for satellite payloads in terms of spatial,temporal,and spectral resolution to establish a Digital *** applications of land satellites under the framework of Digital Earth are introduced from the perspectives of data support,special subject services,and integrated information *** is concluded that China’s land observation satellites and ground processing systems will be fundamental components of the Digital Earth system,in which satellite data and their derived information will serve as the principal information source and greatly promote applications of Digital Earth.

关键词： land satellite Digital Earth spatial information spatial data infrastructure Earth observation

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Penetration performance of W/Cu double-layer shaped charge liners

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Rare Metals 2016年第2期35卷 184-191页

作者： wen-Jian Dong jin-xu Liu Xing-Wang Cheng Shu-Kui Li Qing-He Zou wen-Qi Guo School of Materials Science and Engineering Beijing Institute of Technology Mudanjiang North Alloy Tool Co. Ltd.

Two kinds of W/Cu double-layer shaped charge liner（SCL） were prepared by chemical vapor deposition（CVD） combined with electroforming technique： A SCL with W inner layer and Cu outer layer, B SCL with Cu inner layer and W outer layer. The penetration properties of A and B SCLs were researched. The results show that the two SCLs can form continuous jet and the tip velocities of A and B jets are 7.4 and 6.3 km s^（-1）, respectively. The kinetic energy density（5.3 9 1011 J m-3） of A jet tip increases by 194.4 %compared with that（1.8 9 1011 J m-3） of B jet tip. B jet,however, exhibits deeper penetration depth at the same experimental conditions. The chemical component and microstructure of the area nearby the ballistic perforation were researched. Component analysis shows that both the jets are formed only from inner layer metal. Microstructure analysis shows that martensite and intermetallic form around ballistic perforation penetrated by A SCL due to the intensive interaction between W jet and steel target. The two kinds of newly formed ultrahard phases also hinder the jet from penetrating target further. As a result of relatively alleviative interaction between Cu jet and target, only solid solution rather than ultrahard phases forms around ballistic perforation penetrated by B SCL.

关键词： Shaped charge liner Jet Penetration performance Chemical vapor deposition Electroforming technique

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