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Rare Metals 2023年第2期42卷 713-718页

作者： jia-min zhong Zong-An Li Xiao-Wei Zhang Lin Zhou Zhi-Qiang Wang De-Hong Chen National Engineering Research Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.General Research Institute for Nonferrous MetalsBeijing100088China

In order to solve the problem of large temperature difference between the center and ends of the metallic rod in the purification process of solid-state electrotransport(SSE),three types of electrode connections of tantalum and the corresponding rods of metallic lanthanum were designed,the temperature distributions of three kinds of rod were measured,and the influence of temperature difference on the purification effect of solid-state electrotransport was *** results indicate that the maximum temperature difference of the rod will be significantly reduced through decreasing the cross section of electrode connection to make its unit length resistance close to that of rod,or increasing the unit length resistance of the section at both ends of the *** these two measures are adopted at the same time,the effect of decreasing rod temperature difference is the best in the present study,and the maximum temperature difference of the rod can be reduced to 29℃when the maximum temperature of the rod is 820℃.The migration velocity of the impurities at rod ends can be obviously improved after the rod temperature difference is reduced,which enables the purification effect and efficiency of solid-state electrotransport to be greatly raised;it is also found that the major impurities iron in metallic lanthanum migrates more easily than oxygen and carbon during the purification of metal lanthanum with solid-state electrotransport.

关键词： Solid-state electrotransport Electrode connection Temperature difference Metallic lanthanum Purification effect

Migration regularities of impurities C,O,Fe,Co and Ni and effect of crystal transition on C,O and Fe in purification of metal La by solid-state electrotransport

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Rare Metals 2021年第10期40卷 2985-2992页

作者： jia-min zhong De-Hong Chen Si-ming Pang Zong-An Li Lin Zhou Zhi-Qiang Wang National Engineering Research Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.Beijing 100088China

Migration regularities of impurities C,O,Fe,Co and Ni and the effect of crystal transition on C,O and Fe in purification of metal La by solid-state electrotransport(SSE)were *** impurity migration direction,removal extent and difficulty were intuitively judged by impurity residual rate distribution *** is indicated that major impurities Fe,Co,Ni,C and O in metal La are found to significantly migrate to anode and migration effects are much better with the increase in temperature and prolongation of time in purification of La by *** Fe,Co and Ni in La may be fast diffusion elements,which are very extreme to be removed,and removal difficulty is in the order of Fe

关键词： Solid-state electrotransport Puriﬁcation Lanthanum Impurity distribution Residual rate Crystal transition

Migration regularities of impurity aluminum and copper in purification of metal lanthanum by solid-state electrotransport

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Rare Metals 2021年第8期40卷 2307-2312页

作者： Zhi-Qiang Wang Zong-An Li jia-min zhong De-Hong Chen Xiao-Wei Zhang Lin Zhou National Engineering Research Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.General Research Institute for Nonferrous MetalsBeijing100088China

In view of the previous studies on the migrations of impurity aluminum(Al)and copper(Cu)in purification of rare earth metal by solid-state electrotransport(SSE),there are still some questions about that which direction they migrate to and whether there are significant migrations or *** metal lanthanum(La)was used as research object,and the effects of migration temperature and time on the distributions and migration regularities of impurity Al and Cu were investigated in the present study by increasing concentration of impurity Al and Cu in raw metal *** impurity migration direction and removal difficulty were intuitively judged by the residual rate distribution curve of *** is indicated that metal impurity Al and Cu in metal La at 800℃ with direct current are found to significantly migrate to anode and their residual rates near cathode decrease with the increase in migration temperature and prolongation of migration *** relatively large vapor pressure of Al and Cu makes their residual rate distribution curves being low in middle and high in *** metal La was continuously purified for 100 h at 800℃ by SSE,the residual rates of impurity Al and Cu at 20 mm from cathode are 68.43%and 57.43%,respectively,showing that Cu is much easier to be removed than Al.

关键词： Solid-state electrotransport Purification Residual rate Rare earth metal Lanthanum

Finite-temperature ductility-brittleness and electronic structures of Al_(n)Sc(n=1,2 and 3)

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Rare Metals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan Liu Shu-Chen Sun Hong-Bo Yang jia-min zhong Gan-Feng Tu Song Li Yu-Dong Zhang Claude Esling Hai-Le Yan Liang Zuo Key Laboratory for Anisotropy and Texture of Materials(ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Rare Earth Functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an 071700China Laboratoire d'étude des Microstructures et de Mécanique des Matériaux(LEM3) Unikersitéde Lorraine57045MetzFrance

Finite-temperature ductility-brittleness and electronic structures of Al_(3)Sc,Al_(2)Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al_(3)Sc and Al_(2)Sc are brittle at both ground state and finite temperatures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al_(3)Sc,Al_(2)Sc and AISc improves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from negative to *** T>600 K,AlSc is unequivocally classified as ductile from all criteria *** all compounds,the Al-Al bond originated from s-p and p-p orbital hybridizations,and the Al-Sc bond dominated by p-d covalent hybridization,are the first and second strongest chemical bonds,*** explain the difference in mechanical properties,the mean bond strength(MBS)is introduced in this *** weaker Al-Al bond in AlSc,leading to a smaller MBS,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al-Sc Target materials Intrinsic ductility Finite-temperature elastic constant First-principles calculation

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie jia-Lin Li Ling Gong Xiang-Li zhong Hong-jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Optimizing cooling approach of spiral coil for an electromagnetic steel teeming system of ladle in continuous casting production

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Journal of Iron and Steel Research International 2025年第1期32卷 85-94页

作者： ming He Qing-wei Wang Li-jia Zhao Wang-zhong Mu Xing-an Liu Qiang Wang College of Horticulture Shenyang Agricultural UniversityShenyang110866LiaoningChina Key Laboratory of Electromagnetic Processing of Materials(ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Protected Horticulture(ministry of Education) Shenyang Agricultural UniversityShenyang110866LiaoningChina Department of Materials Science and Engineering KTH Royal Institute of TechnologyStockholm10044Sweden

To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been *** means of spiral coil in this technology is directly related to its service ***,heat transfer processes of air cooling and spray cooling were compared and ***,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling *** maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally *** simulation was applied to examine the coil temperature variation with different cooling systems and *** coil operation,spray cooling is said to be more *** controlling the water flow rate and air flow rate,the spray cooling effect is ***,water temperature has little or no impact when using spray *** cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil *** the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.

关键词： Electromagnetic induction controlled automated steel teeming technology Spiral coil Spray cooling Heat transfer Continuous casting

汞矿区周边土壤重金属空间分布特征、污染与生态风险评价

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环境科学 2021年第6期42卷 3018-3027页

作者：王锐邓海贾中民王佳彬余飞曾琴琴重庆市地质矿产勘查开发局川东南地质大队重庆400038 重庆市土地质量地质调查重点实验室重庆400038 中国地质调查局成都地质调查中心成都610081

为探明汞矿开采对周边土壤环境及人体健康的影响,在重庆市酉阳县某汞矿聚集区周边采集表层土壤组合样42件,分析了土壤中重金属(Cd、Hg、Pb、As、Cr、Cu、Zn和Ni)的含量及p H,对土壤重金属含量的空间分布特征、污染程度和生态风险进行了... 详细信息

为探明汞矿开采对周边土壤环境及人体健康的影响,在重庆市酉阳县某汞矿聚集区周边采集表层土壤组合样42件,分析了土壤中重金属(Cd、Hg、Pb、As、Cr、Cu、Zn和Ni)的含量及p H,对土壤重金属含量的空间分布特征、污染程度和生态风险进行了研究.结果显示,研究区土壤重金属表层富集明显,参照《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB15618-2018)发现,土壤Cd、Hg、Pb、As和Zn存在不同程度的超标现象.土壤存在一定程度的污染和生态风险,土壤重金属中度-重度污染和强生态风险区均分布在矿点周围,说明矿业活动对土壤环境的影响.土壤Cr、Cu和Ni含量可能受到母岩的风化和成土作用的影响,土壤Hg、Pb和Zn可能受到矿产开采等人为活动的影响,土壤Cd和As同时受到地质背景和人为活动的影响.重金属对成人的健康影响较小,对儿童造成健康风险的概率较大,土壤As是造成人体健康风险的主要贡献因子,8种重金属均以经口摄入途径的贡献率最高.汞矿的开采是造成研究区土壤污染及生态风险的主要原因.

关键词：汞矿区土壤重金属分布特征土壤污染生态风险

A novel method for simultaneous measurement of^(222)Rn and^(220)Rn progeny concentrations measured by an alpha spectrometer

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Nuclear Science and Techniques 2025年第1期36卷 127-139页

作者： zhong-Kai Fan jia-Le Sun Hao-Xuan Li Xiang-ming Cai Hui Yang Shou-Kang Qiu Yan-Liang Tan jian Shan School of Nuclear Science and Technology University of South ChinaHengyang 421001China College of Physics and Electronic Engineering Hengyang Normal UniversityHengyang 421008China

The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222)Rn and^(220)Rn progeny concentrations by measuring the total alpha counts at five time intervals within 560 min should be expected only in the case of high progeny concentrations in *** complete the measurement within a relatively short period and adapt it for simultaneous measurements at comparatively lower^(222)Rn and^(220)Rn progeny concentrations,a novel mathematical model was proposed based on the radioactive decay *** model employs a nonlinear fitting method to distinguish nuclides with overlapping spectra by utilizing the alpha particle counts of non-overlapping spectra within consecutive measurement cycles to obtain the concentrations of^(222)Rn and^(220)Rn progeny in *** verification experiments were conducted using an alpha *** experimental results demonstrate that the concentrations of^(222)Rn and^(220)Rn progeny calculated by the new method align more closely with the actual circumstances than those calculated by the total count method,and their relative uncertainties are all within±16%.Furthermore,the measurement time was reduced to 90 min,representing an acceleration of 84%.The improved capability of the new method in distinguishing alpha particles with similar energies emitted from ^(218)Po and^(212)Bi,both approximately 6 MeV,contributed to realizing more accurate *** proposed method has the potential advantage of measuring relatively low concentrations of^(222)Rn and^(220)Rn progeny in air more quickly via air filtration.

关键词： ^(222)Rn ^(220)Rn Progeny concentration Nonlinear fitting method Alpha spectrometer

典型喀斯特地区土壤-作物系统镉的富集特征与污染评价

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环境科学 2021年第2期42卷 941-951页

作者：王锐邓海贾中民严明书周皎董金秀王佳彬余飞重庆市地质矿产勘查开发局川东南地质大队重庆400038 重庆市土地质量地质调查重点实验室重庆400038

为了研究喀斯特地区Cd在表层土壤和农作物中的富集特征及影响因素,为土地安全利用提供理论依据,选择在重庆市黔江区中部采集表层土壤样品360件、深层土壤样品7件、85件水稻样品和73件玉米样品(配套采集根系土样),分析了土壤及农作物中C... 详细信息

为了研究喀斯特地区Cd在表层土壤和农作物中的富集特征及影响因素,为土地安全利用提供理论依据,选择在重庆市黔江区中部采集表层土壤样品360件、深层土壤样品7件、85件水稻样品和73件玉米样品(配套采集根系土样),分析了土壤及农作物中Cd的含量、土壤中TFe2O3、Mn、有机质(C_(org))、Se等含量和土壤pH.基于地统计法分析了表层土壤Cd的空间分布特征及富集原因,并对土壤及农作物进行了安全评价.结果表明,表层土壤Cd空间分布不均匀,且表层富集明显,表层土壤Cd含量受到成土母质和人为活动的控制,表层富集主要受到铁锰氧化物和有机质(C_(org))的影响.土壤Cd以无污染和轻度污染为主,部分区域存在强生态风险,污染区主要位于二叠系地层分布区,土壤Cd污染主要受到地质背景的控制.大宗农作物均存在一定程度的Cd轻微-重度污染,水稻的日均建议消耗量的限值为0.87 kg·d^(-1),玉米为1.53 kg·d^(-1).Cd的生物有效性受到土壤酸碱度和土壤Se含量的影响,酸性条件下Cd生物有效性高,土壤高Se区农作物较安全.建议在水田乡二叠系出露区种植Cd低累积作物,或通过调节土壤酸碱度,控制Cd的污染风险,实现土地安全利用.此外,优先选择在土壤高Se区种植农作物.

关键词：喀斯特地区土壤和农作物镉元素富集特征影响因素安全评价

Exploring the performance of large language models on hepatitis B infection-related questions:A comparative study

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World Journal of Gastroenterology 2025年第3期31卷 103-112页

作者： Yu Li Chen-Kai Huang Yi Hu Xiao-Dong Zhou Cong He jia-Wei zhong Department of Gastroenterology Jiangxi Provincial Key Laboratory of Digestive DiseasesJiangxi Clinical Research Center for GastroenterologyDigestive Disease HospitalThe First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina HuanKui Academy Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Patients with hepatitis B virus(HBV)infection require chronic and personalized care to improve *** language models(LLMs)can potentially provide medical information for *** To examine the performance of three LLMs,ChatGPT-3.5,ChatGPT-4.0,and Google Gemini,in answering HBV-related *** LLMs’responses to HBV-related questions were independently graded by two medical professionals using a four-point accuracy scale,and disagreements were resolved by a third *** question was run three times using three *** was assessed via the Gunning Fog index and Flesch-Kincaid grade *** Overall,all three LLM chatbots achieved high average accuracy scores for subjective questions(ChatGPT-3.5:3.50;ChatGPT-4.0:3.69;Google Gemini:3.53,out of a maximum score of 4).With respect to objective questions,ChatGPT-4.0 achieved an 80.8%accuracy rate,compared with 62.9%for ChatGPT-3.5 and 73.1%for Google *** the six domains,ChatGPT-4.0 performed better in terms of diagnosis,whereas Google Gemini demonstrated excellent clinical ***,in the readability analysis,the mean Gunning Fog index and Flesch-Kincaid grade level scores of the three LLM chatbots were significantly higher than the standard level eight,far exceeding the reading level of the normal *** Our results highlight the potential of LLMs,especially ChatGPT-4.0,for delivering responses to HBV-related *** may be an adjunctive informational tool for patients and physicians to improve ***,current LLMs should not replace personalized treatment recommendations from physicians in the management of HBV infection.

关键词： ChatGPT-3.5 ChatGPT-4.0 Google Gemini Hepatitis B infection Accuracy