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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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Data-driven mapping-relationship mining between hardness and mechanical properties of dual-phase titanium alloys via random forest and statistical analysis

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Rare Metals 2024年第2期43卷 829-841页

作者： Hai-Chao Gong Qun-Bo Fan Hong-Mei zhang Xing-Wang Cheng Wen-Qiang Xie Kai Chen Lin Yang jun-jie zhang Bing-Qiang Wei Shun Xu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401135China Department of Mechanical and Materials Engineering University of Nebraska-LincolnLincolnNE68588USA

In order to accelerate the research on the property optimization of titanium alloy based on high-throughput methods,it is necessary to reveal the relationship between hardness and other mechanical properties which is still *** this work,taking Ti20C alloy as research object,almost all the microstructure of dual-phase titanium alloys were covered by traversing over 100 heat treatment ***,massive experiments including microstructure characterization and performance test were conducted,obtaining 51,590 pieces of microstructure data and 3591 pieces of mechanical property ***,based on large-scale data-driven technology,the quantitative mapping relationship between hardness and other mechanical properties was deeply *** results of random forest models showed that the correlation between hardness(H)and Charpy impact energy(A_(k))(or elongation,A)was hardly dependent on the microstructure types,while the relationship between H and tensile strength(R_(m))(or yield strength,R_(p0.2))was highly dependent on microstructure ***,combined with statistical analysis,it was found that the relationship between H and Ak(or A)were negatively ***,the relationship between H and strength was positively linear for equiaxed microstructure,and strength was linked to d^(−1/2)(d,equivalent circle diameter)ofα-grains in the form of classical Hall–Petch formula;but for other microstructures,the relationships were ***,the above rules were nearly the same in the rolling direction and transverse ***,a"four-quadrant partition map"between H and R_(p0.2)/R_(m) was established as a versatile material-screening tool,which can provide guidance for on-demand selection of titanium alloys.

关键词： Dual-phase titanium alloy Data-driven Hardness Mapping relationship

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宁夏荒漠草原典型灌丛根际土壤酶活性及微生物代谢多样性

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草业学报 2024年第9期33卷 1-14页

作者：姚佳妮刘爽张钧杰胡明珠代金霞宁夏大学生命科学学院宁夏银川750021

开展荒漠灌丛根际土壤酶活性和微生物代谢多样性研究,对于荒漠土壤的生态修复具有重要意义。运用可见分光光度法和Biolog微平板法,对宁夏白芨滩荒漠草原内柠条、沙冬青、毛刺和猫头刺4种典型的豆科灌丛不同发育期根际土壤酶活性及微生... 详细信息

开展荒漠灌丛根际土壤酶活性和微生物代谢多样性研究,对于荒漠土壤的生态修复具有重要意义。运用可见分光光度法和Biolog微平板法,对宁夏白芨滩荒漠草原内柠条、沙冬青、毛刺和猫头刺4种典型的豆科灌丛不同发育期根际土壤酶活性及微生物代谢功能多样性进行了研究。结果表明:不同灌丛各发育期根际土壤的酶活性存在显著差异。从灌丛种类来看,沙冬青根际土壤脲酶活性均显著高于其他3种灌丛,毛刺根际土壤碱性磷酸酶活性均显著低于其他灌丛。从发育期来看,营养期沙冬青根际土壤脲酶和碱性磷酸酶活性显著高于其他时期,柠条根际土壤脲酶和蔗糖酶活性显著低于其他时期;盛花期柠条根际土壤脲酶和碱性磷酸酶活性、沙冬青根际土壤蔗糖酶活性、猫头刺根际土壤脲酶和脱氢酶活性显著高于其他时期;果实期沙冬青根际土壤脲酶和碱性磷酸酶活性最高,柠条根际土壤蔗糖酶和脱氢酶活性最高;毛刺的盛花期和果实期根际土壤中酶活性普遍较低。不同灌丛各发育期根际土壤微生物群落代谢多样性大多存在显著差异。4种灌丛根际土壤平均颜色变化率(average well color development,AWCD)均随培养时间的延长而逐渐增加,碳源利用类型主要为碳水化合物、氨基酸和羧酸。柠条营养期根际土壤中微生物分布较均匀,代谢活性强,生长旺盛。主成分分析(principal component analysis,PCA)显示,营养期沙冬青、毛刺和猫头刺根际土壤微生物的碳源利用模式相似;盛花期柠条、沙冬青和猫头刺根际土壤微生物的碳源利用模式相似;果实期柠条和沙冬青、毛刺和猫头刺根际土壤微生物的碳源利用模式相似。随着发育期的变化,土壤微生物碳源利用模式发生不同程度的变化。冗余分析(redundancy analysis,RDA)显示,酶活性和微生物代谢功能与土壤理化性质关系密切。脲酶与铵态氮(NH_(4)^(+)-N)正相关;碱性磷酸酶与土壤含水量(SWC)显著正相关;蔗糖酶与全氮(TN)、铵态氮(NH_(4)^(+)-N)、土壤有机质(SOM)和全磷(TP)正相关,且与TN显著正相关;TN、有效磷(AP)、TP、速效钾(AK)和亚硝态氮(NO_(2)^(-)-N )显著影响脱氢酶活性。NH_(4)^(+)-N、NO_(2)^(-)-N 、TP、AP和NO_(3)^(-)-N是影响微生物代谢多样性的主要理化因子。该研究结果对于了解宁夏荒漠根际土壤微环境以及微生物群落对环境响应特征具有积极意义。

关键词：豆科灌丛土壤酶活性 Biolog法碳源利用代谢多样性

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α-Ni(OH)2 electrodeposition from NiCl2 solution

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Transactions of Nonferrous Metals Society of China 2020年第10期30卷 2802-2811页

作者： jun-jie zhang Ting-an zhang Sen FENG School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Northeastern UniversityShenyang 110819China

α-Ni(OH)2 was synthesized from a NiCl2 solution by electrodeposition *** order to conduct a systematic study on the effects of experimental parameters,a series of electrolyte initial pH values,current densities,electrodeposition temperatures,and electrodeposition time were *** voltammetry results demonstrated a side reaction of Ni^2++2e→*** X-ray diffraction analysis,Fourier-transform infrared spectrum,and the color of the product showed that pureα-Ni(OH)2 could be obtained in the initial pH value range of 2−5.86,current density range of 10−25 mA/cm^2,electrodeposition temperature range of 25−35℃,and electrodeposition time range of 1.0−3.0 *** electrodeposition temperature increased to 45℃,a mixture ofα-Ni(OH)2 and metallic Ni was obtained.A current density higher than 30 mA/cm^2 resulted in the sample with features ofβ-Ni(OH)2.A small amount of metallic Ni existed in the as-prepared sample when current density decreased to 5 mA/cm^2.A slight increase of electrolyte pH was observed with increasing initial solution pH and current *** mass revealed a slight decrease with initial pH decreasing and showed an almost linear increase with current density *** slope of the curve for electrodeposition mass versus electrodeposition time remained stable in the first 2.0 h and then decreased.

关键词： α-Ni(OH)2 NiCl2 electrodeposition electrolyte initial pH current density electrodeposition temperature electrodeposition time

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Microstructure and properties of microarc oxidation coating formed on aluminum alloy with compound additives nano-TiO_2 and nano-ZnO

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Rare Metals 2018年第11期37卷 976-982页

作者： Ting-Yi Lin Xiao-Yan zhang Xin Huang Xiang-Peng Gong jun-jie zhang Xie-jun Hu College of Materials and Metallurgy Guizhou University

In this work, microarc oxidation(MAO) technology was used to form oxide ceramic coating on the surface of aluminum alloy. The combined additives nano-TiOand nano-ZnO were added into the silicate electrolyte, and the effect of the compound nano-additive on microstructure and properties of MAO coating was investigated. The results show that compared with those of the nano-additive-free coating formed on aluminum alloy, the thickness, hardness, abrasion resistance and corrosion resistance of the nano-additive-containing coating are obviously improved. The surface of coating with nanoadditive becomes smooth, dense, and there are less porosities and microcracks. Moreover, the content of crystal phase a-AlOand y-AlOincreases visibly on the nano-additive-containing MAO coatings, and new phases AlTi and ZnTiare detected in the coatings, which are mainly contributed to the excellent corrosion resistance and abrasion resistance of the film. When the contents of nano-TiOand nano-ZnO are, respectively, 4 and 2 g-L, the film has better comprehensive performance, the thickness and hardness of the film could reach 52 μm and HV 692,respectively.

关键词： Microarc oxidation Nano-TiO_2 Nano-ZnO Aluminum alloy Property

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Preparation of glass–ceramics from high-chlorine MSWI fly ash by one-step process

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Rare Metals 2021年第11期40卷 3316-3328页

作者： Shi-Zhen Zhao Xiao-Yan zhang Bo Liu jun-jie zhang Han-Lin Shen Shen-Gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

Municipal solid waste incinerated(MSWI) fly ash contains heavy metals and chloride,which is urgent to be disposed via an effective ***,glass-ceramics,one of the recycling waste materials based on MSWI fly ash with high chloride content,have been developed from one-step *** fly ash and waste glass have been utilized as calcium and silicon sources,***-ceramics were successfully prepared by the one-step *** is found that the increase in MSWI fly ash promotes the fracture of glass mesh(Si-O)and the generation of non-bridging oxygen,reducing the polymerization degree of glass network structure,which leads to the decrease in glass *** difference between glass transition temperature(T_(g)) and crystallization temperature(T_(c)) was narrowed,and crystallization activation energy of basic glass was reduced,which promoted *** lower crystallization activation energy(E=217.56 kJ·mol^(-1)) and high utilization rate of 50 wt% MSWI fly ash,the optimal glass-ceramics with spherical diopside,cuspidine and glass phase,excellent hardness of 7.97 GPa and bending resistance of 114.86 MPa are *** is worth mentioning that most of the high content of chlorine in MSWI fly ash will evaporate during vitrification process;the residual chlorine as well as heavy metals can be present steadily in crystalline ***,this study not only increases the attachment value of MSWI fly ash,but also eliminates the problems caused by high chlorine and heavy metals in MSWI fly ash.

关键词： Municipal solid waste incinerated(MSWI)fly ash Glass–ceramics Crystallization behavior Microstructure Properties Chlorine

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Association of glutathione peroxidase-1 （GPx-1） rs1050450 Pro198Leu and Pro197Leu polymorphisms with cardiovascular risk：a meta-analysis of ob-servational studies

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Journal of Geriatric Cardiology 2014年第2期11卷 141-150页

作者： jun-Xia zhang Zhi-Mei WANG jun-jie zhang Lin-Lin ZHU Xiao-Fei GAO Shao-Liang CHEN Department of Cardiology Nanjing First Hospital Affiliated to Nanjing Medical University Nanjing Jiangsu Province 210006 China

Objective To clarify the association between rs1050450 polymorphism in Glutathione peroxidase-1 （GPx-1） and the risk of cardi-ovascular diseases （CVD） by performing a meta-analysis of published studies. There is growing evidence from different study types for an association of the GPx-1 polymorphism and cardiovascular outcomes, but observational studies have so far shown inconsistent results. Me-thods Relevant publications were searched through PubMed, Embase database databases and the Cochrane Library. We used odds ratios （ORs） with 95%confidence intervals （CIs） to assess the strength of association under the best genetic model. Both Q statistic and the I2 were used to check heterogeneity. Meta-regression analysis was performed to explore heterogeneity source. Sensitivity analysis, cumulative me-ta-analysis analysis and publication bias were used to test the reliability of the results. Results Data were available from two cohort studies and 8 case-control studies involving 1,430 cases and 3,767 controls. The pooled ORs for overall CVD risk was 1.36 with 95%CI：1.08-1.70 under a co-dominant model, and that for East Asian subgroup was 1.84 （95%CI：1.39-2.43）. Substantial heterogeneity for ORs were de-tected among all the included studies, mainly caused by ethnic differences between East Asian and non-East Asian populations. Although Egger＇s regression test suggested no statistical significant publication bias, Begg＇s funnel plot exhibited obvious asymmetry. The statistical significance disappeared after adjusting for potential publication bias in the overall studies. However, no substantial publication bias was found in the East Asian subgroup. Conclusions GPx-1 gene Pro198Leu and Pro197Leu polymorphisms considerably increased the risk of CVD in the East Asian population. Large-scale investigations are needed to confirm the results in different ethnicities.

关键词： Glutathione peroxidase-1 Cardiovascular diseases Polymorphism Meta-analysis

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Effect of chip rate on the ranging accuracy in a regenerative pseudo-noise ranging system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 132-139页

作者： Jian-wen JIANG Wei-jun YANG Chao-jie zhang Xiao-jun JIN Zhong-he JIN Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The ranging accuracy of a pseudo-noise ranging system is mainly decided by range jitter and time delay discrimination. Many factors can affect the ranging accuracy, one of which is the chip rate. In digital signal processing, the time delay discrimination and autocorrelation function of sampled ranging sequences of different chip rates are very different. An approximation simulation model is established according to an in-phase quadrature (I/Q) correlator which is used to evaluate the time delay. Simulation results of the range jitter and time delay discrimination show that the chip rate which provides a non-integer sample-to-chip rate ratio can achieve a higher ranging accuracy, and some test results validate the simulation model. In some design missions, the simulation results may help to select an optimum sample-to-chip rate ratio to satisfy the design requirement on the ranging accuracy.

关键词： Ranging accuracy Range jitter Time delay discrimination Sample-to-chip rate ratio Integration time Autocorrelation function Fractional chip period delay

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A new method for direct synthesis of Li2CO3 powders by membrane electrolysis

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Rare Metals 2018年第8期37卷 716-722页

作者： Xi-Juan Pan Ting-An zhang Zhi-He Dou Guo-Zhi Lyu Xiu-Xiu Han jun-jie zhang School of Metallurgy Northeastern University Shenyang 110819 China Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Education Ministry Shenyang 110819China

A new method for the direct synthesis of Li2CO3 powders by membrane electrolysis from LiC1 solution is demonstrated in this paper, where a novel electrolysis system combining ventilation, agitation and loop filtration functions was reported. The aim of this work is to explore the effect of the starting concentration of LiC1 on the phase and micromorphology of Li2CO3 crystals and thereafter to explore the mechanism of crystallization and grain growth law. Scanning electron microscopy （SEM） images indicate that the particles become irregular polycrystalline from well-defined flower-like and the micro-crystals change from lamellar to needle-like and subsequently to smaller globular granules, and the surface of the crystals becomes smooth with LiC1 concentration increasing from 50 to 400 g.L^-3. The crystalline phases of the different samples were characterized using powder X-ray diffraction （XRD） and the results prove that pure LiaCO3 crystals can be obtained in a single step by the electrolysis method. The particle size distributions show that both volume mean crystal sizes and the full width at half maximum （FWHM） decrease when the starting LiC1 concentration increases from 50 to 300 g.L 3 and also decreases from 400 to 300 g-L^-3.

关键词： Lithium carbonate Lithium chloride Membrane electrolysis Carbon dioxide

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Management with the insufficient proximal landing zone for endovascular repair in aortic dissection

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Chinese Medical Journal 2011年第19期124卷 3003-3007页

作者： MA Hao YANG Hong-yu ZOU jun-jie zhang Xi-wei Department of General Surgery the First Affiliated HospitalNanjing Medical University Department of General Surgery Jiangsu Province Hospital Nanjing Jiangsu 210029 China

Background Sufficient length of the proximal landing zone （PLZ） is the key for a successful thoracic endovascular aortic repair （TEVAR） of an aortic lesion. The aim of this research was to investigate the safety, feasibility, efficacy, and problems of endovascular repair for aortic dissection with insufficient *** The clinical data between August 2005 and February 2010 from patients with insufficient PLZ for endovascular repair of aortic dissection were retrospectively reviewed. According to the classification proposed by Ishimaru, aortic zone 0 was involved in 3 cases, zone 1 in 10 cases, and zone 2 in 11 cases. A hybrid surgical procedure of supraortic debranching and revascularization, directly coverage the orifice of left subclavian artery, or a left common carotid artery chimney graft technique were performed to obtain an adequate proximal aortic landing *** There was no significant difference in risk factors and diameter of the PLZ between Zone 0, Zone 1, and Zone 2. But the length of the PLZ was significantly different in the three groups （P 〈0.01）. There was no significant difference in technical and clinical success rate between the *** The procedure for extending an insufficient PLZ for endovascular repair for aortic arch pathology is feasible and relatively safe. The applicability of TEVAR in such aortic disorders may be expanded.

关键词： endovascular procedures aortic dissection proximal landing zone aorta, thoracic

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