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Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 377-385页

作者： Cong Xu Hong-wei Cheng guang-shi li Chang-yuan Lu xiong-gang Lu Xing-li Zou Qian Xu State Key Laboratory of Advanced Special Steel & School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Calcination Chemicals removal (water treatment) Chlorination Leaching Metal recovery Nickel Rare earths Sulfur compounds Temperature X ray diffraction

Analysis of CVC roll contour and determination of roll crown

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Journal of University of Science and Technology Beijing 2007年第4期14卷 378-380页

作者： guang Xu Xianjun liu Jiarong Zhao Junwei xiong Key Laboratory of the Ministry of Education for Ferrous Metallurgy and Resources Utilization Wuhan University of Science and Technology Wuhan 430081 China

Mathematical analysis of continuous variable crown （CVC） roll contour used in CSP production line was conducted and the roll contour function of CVC roll was obtained. The validation with actual CVC roll contour shows that the calculation values of the roll contour function and the actual roll contour parameters given by equipment provider are the same, which proves that the roll contour function of CVC rolls given in this article is correct. The nonlinear relationship between the roll crown of CVC rolls and roll shift amounts was deduced. The concept of crown extremum was given.

关键词： CVC roll roll contour crown extremum axial shift

Eogenetic Karst in Interbedded Carbonates and Evaporites and Its Impact on Hydrocarbon Reservoir: A New Case from Middle Triassic Leikoupo Formation in Sichuan Basin, Southwest China

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Journal of Earth Science 2019年第5期30卷 908-923页

作者： Hong liu Xiucheng Tan ling li xiong Ding Jian Cao guang Yang Teng Ma State Key Laboratory of Oil and Gas Geology and Exploitation Southwest Petroleum University Chengdu 610500 China School of Earth Sciences and Technology Branch of Sedimentology and Hydrocarbon Accumulation CNPC Key Laboratory of Carbonate Reservoir Southwest Petroleum University Chengdu 610500 China Department of Earth Sciences Nanjing University Nanjing 210023 China Institute of Petroleum Exploration and Exploitation PetroChina Southwest Oil and Gas Field Company Chengdu 610051 China

Karst in interbedded carbonates and evaporites has been reported to have important and complex impacts on reservoir. It is significant for exploration and karst geology. Here, we report such a new case from Middle Triassic Leikoupo Formation of Sichuan Basin, Southwest China. Stratigraphic incompleteness and the occurrence of unconformity provide evidence for the presence of eogenetic karst. Under the impact of this eogenetic karst, residual weathered and solution-collapse breccia, solution pores and silicification and dedolomitization have been observed. Classic stratigraphic zonation of karst is not readily distinguishable, which is ascribed to the stratigraphic collapse of carbonate rocks resulting from the dissolution of evaporites by lateral subsurface fluid flow. In terms of impact on reservoir quality, karst can generally improve the initial physical property of the porous layers in theory. However, subsurface fluid flow dissolved the evarporitic beds and facilitated the collapse of overlying strata. As a consequence, the lateral continuity of the reservoirs would be destroyed, and relatively high-quality reservoirs can only be developed with little collapse of overlying strata, reflecting reservoir heterogeneities. This may be a general feature of reservoir formation under the impact of karst in interbedded carbonates and evaporites.

关键词： karst carbonate reservoir evaporite Middle Triassic Leikoupo Formation Sichuan Basin

Infant with reverse-transcription polymerase chain reaction confirmed COVID-19 and normal chest computed tomography:A case report

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World Journal of Clinical Cases 2022年第27期10卷 9845-9850页

作者： guang-Hai Ji Bo li Zu-Chuang Wu Wei Wang Hao xiong Department of Radiology The First Affiliated Hospital of Yangtze UniversityThe First People’s Hospital of JingzhouJingzhou 434000Hubei ProvinceChina Department of Pediatric The First Affiliated Hospital of Yangtze UniversityJingzhou 434000Hubei ProvinceChina Department of Clinical Laboratory The First Affiliated Hospital of Yangtze UniversityJingzhou 434000Hubei ProvinceChina

BACKGROUND Coronavirus disease-2019(COVID-19)is a highly pathogenic respiratory disease that mainly affects adults and elderly ***,over the past three years,there were an increasing number of infected children;however,only a few cases of infants with reverse-transcription polymerase chain reaction(RT-PCR)-confirmed COVID-19 and chest computed tomography(CT)normal have been ***,we reported a single case of a patient(a 3-mo-old girl)with COVID-19,including her clinical and imaging *** SUMMARY The patient with fever,diarrhea came to fever *** chest CT was *** patient was treated accordingly,the fever disappeared while diarrhea persisted,what’s more,RT-PCR testing of nasopharyngeal swab showed positive results;thus,the patient was admitted to the pediatric department on the 5 th day of *** child was given systematic treatment,and all her symptoms significantly *** RT-PCR tests were negative after examining the pharyngeal swabs but positive after analyzing anal *** was discharged on the 31 st day of *** This report provides useful references for treating infantile COVID-19 cases with diarrhea or other non-respiratory symptoms and normal chest CT *** the persistent positive RT-PCR results of anal swabs,the possibility of fecal-oral transmission of COVID-19 should be considered.

关键词： Infant COVID-19 SARS-CoV-2 Tomography Case report

A comparative study of fuzzy weights of evidence and random forests for mapping mineral prospectivity for skarn-type Fe deposits in the southwestern Fujian metallogenic belt, China

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Science China Earth Sciences 2016年第3期59卷 556-572页

作者： ZHANG Zhen Jie ZUO Ren guang xiong Yi Hui School of Earth Sciences and Resources China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Recent studies have pointed out that the widespread iron deposits in southwestern Fujian metallogenic belt(SFMB)(China) are skarn-type deposits associated with the Yanshanian granites. There is still excellent potential for mineral exploration because large areas in this belt are covered by forest. A new predictive model for mapping skarn-type Fe deposit prospectivity in this belt was developed and focused on in this study, using five criteria as evidence:(1) the contact zones of Yanshanian granites(GRANITE);(2) the contact zones within the late Paleozoic marine sedimentary rocks and the carbonate formations(FORMATION);(3) the NE-NNE-trending faults(FAULT);(4) the zones of skarn alterations(SKARN); and(5) the aeromagnetic anomaly(AEROMAGNETIC). The fuzzy weights of evidence(FWof E) method, developed from the classical weights of evidence(Wof E) and based on fuzzy sets and fuzzy probabilities, could provide smaller variances and more accurate posterior probabilities and could effectively minimize the uncertainty caused by omitted or wrongly assigned data and be more flexible than the Wof E. It is an efficient and widely used method for mineral potential mapping. Random forests(RF) is a new and useful method for data-driven predictive mapping of mineral prospectivity method, and needs further scrutiny. Both prospectivity results respectively using the FWof E and RF methods reveal that the prediction model for the skarn-type Fe deposits in the SFMB is successful and efficient. Both methods suggested that the GRANITE and FORMATION are the most valuable evidence maps, followed by SKARN, AEROMAGNETIC, and FAULT. This is coincident with the skarn-type Fe deposit mineral model in the SFMB. The unstable performance experienced when FORMATION was omitted might indicate that the highest uncertainty and risk in follow-up exploration is related to the sequences. In addition, the performance of the RF method for the skarn-type Fe deposits prospectivity in the SFMB is better than

关键词： Mineral prospectivity mapping Fuzzy weights of evidence Random forest Skarn-type Fe Makeng deposit

BOUNDEDNESS OF SOLUTIONS FOR SUPERliNEAR REVERSIBLE SYSTEMS

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Chinese Annals of Mathematics,Series B 2001年第1期22卷 31-46页

作者： li xiong Department of Mathematical Sciences Tsinghua University Beijing 100084 China

This paper is concerned with the boundedness of solutions for second order differential equations x + f(x, t)x + g(x, t) = 0, which are neither dissipative nor conservative, and where the functions f and g are odd in x and even in t, which are 1-periodic in t, and the function g satisfies g(x,t/x+, as|x| - +. Using the KAM theory for reversible systems, the author proves the existence of invariant tori and thus the boundedness of all the solutions and the existence of quasiperiodic solutions and subharmonic solutions.

关键词： Boundedness of solutions Quasiperiodic solutions Subharmonic solutions KAM theory Reversible systems

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低氧暴露后大鼠外周血及骨髓红系的变化

中国组织工程研究 2025年第25期29卷 5390-5395页

作者：熊华李金杰王璐马婕青海大学附属医院(临床医学院) 青海省西宁市810001

背景:低氧暴露下大鼠外周血红细胞变化与骨髓有核红细胞增殖变化相关。低氧诱导因子、促红细胞生成素等相关调控因素参与其中。目的:探讨大鼠低氧暴露后外周血红细胞及骨髓有核红细胞的变化特点及相关因素。方法:模拟海拔5000 m的低压... 详细信息

背景:低氧暴露下大鼠外周血红细胞变化与骨髓有核红细胞增殖变化相关。低氧诱导因子、促红细胞生成素等相关调控因素参与其中。目的:探讨大鼠低氧暴露后外周血红细胞及骨髓有核红细胞的变化特点及相关因素。方法:模拟海拔5000 m的低压低氧环境建立实验大鼠模型,对照组大鼠饲养在海拔2260 m的实验室内,对比低氧暴露前后大鼠血常规、骨髓有核红细胞比例及低氧诱导因子、促红细胞生成素等相关指标。结果与结论:①实验组大鼠外周血红细胞计数、血红蛋白、红细胞压积等指标较对照组升高(P<0.05);②实验组大鼠骨髓CD71^(+)有核红细胞比例较对照组升高(P<0.05);③实验组大鼠骨髓CD71^(+)有核红细胞中低氧诱导因子2α表达水平较对照组升高(P<0.05);④实验组大鼠骨髓上清液促红细胞生成素水平较对照组升高(P<0.05)。结果表明,低氧暴露后大鼠外周血红细胞及骨髓有核红细胞比例增高,可能与骨髓有核红细胞中低氧诱导因子2α及骨髓上清液中促红细胞生成素水平增高有关。

关键词：低氧大鼠外周血红细胞骨髓有核红细胞

From strangelets to strange stars:a unified description

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Science Bulletin 2016年第2期61卷 172-177页

作者： Cheng-Jun Xia guang-xiong Peng En-guang Zhao Shan-Gui Zhou State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences Theoretical Physics Center for Science Facilities Institute of High Energy Physics Synergetic Innovation Center for Quantum Effects and Application Hunan Normal University Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator

The conventionally separated treatments for strangelets and strange stars are now unified with a more comprehensive theoretical description for objects ranging from strangelets to strange stars. After constraining the model parameter according to the Witten–Bodmer hypothesis and observational mass–radius probability distribution of pulsars, we investigate the properties of this kind of objects. It is found that the energy per baryon decreases monotonically with increasing baryon number and reaches its minimum at the maximum baryon number, corresponding to the most massive strange star. Due to the quark depletion,an electric potential well is formed on the surface of the quarkpart. For a rotational bare strange star, a magnetic field with the typical strength in pulsars is generated.

关键词： Strangelets Strange stars Strangequark matter Unified description Witten-Bodmerhypothesis

Heparinized PGA host-guest hydrogel loaded with paracrine products from electrically stimulated adipose-derived mesenchymal stem cells for enhanced wound repair

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Engineered Regeneration 2023年第3期4卷 225-237页

作者： Mengyao li Junliang li Xueru xiong Yushi Wang Yong-guang Jia Xuetao Shi Xiaoling Fu School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou International CampusGuangzhou 511442China National Engineering Research Center for Tissue Restoration and Reconstruction and Innovation Center for Tissue Restoration and Reconstruction Guangzhou 510006China Key Laboratory of Biomedical Engineering of guangdong Province South China University of TechnologyGuangzhou 510006China

The microenvironment of the wound bed is essential in the regulation of wound *** this regard,strategies that provide a repairing favorable microenvironment may effectively improve healing ***,we attempted to use electrical stimulation(ES)to boost the paracrine function of adipose-derived stem cells from rats(rASCs).By examining the concentrations of two important growth factors,VEGF and PDGF-AA,in the cell culture supernatant,we found that ES,especially 5𝜇A ES,stimulated rASCs to produce more paracrine factors(5𝜇A-PFs).Further studies showed that ES may modulate the paracrine properties of rASCs by upregulating the levels of TRPV2 and TRPV3,thereby inducing intracellular Ca^(2+) *** deliver the PFs to the wound to effectively improve the wound microenvironment,we prepared a heparinized PGA host-guest hydrogel(PGA-Hp hydrogel).Moreover,PGA-Hp hydrogel loaded with 5𝜇A-PFs effectively accelerated the repair process of the full-thickness wound model in *** findings revealed the effects of ES on the paracrine properties of rASCs and highlighted the potential application of heparinized PGA host-guest hydrogels loaded with PFs derived from electrically stimulated rASCs in wound repair.

关键词： Wound repair Electrical stimulation Paracrine factors Heparinized PGA host-guest hydrogel