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Serum Zinc and Copper Level in Juvenile Idiopathic Arthritis (JIA) Patients and Its Correlation with Disease Duration-A Tertiary Hospital Study
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作者 Mohammad Imnul Islam Mujammel Haque +4 位作者 Tanzida Sultana Mousumi Ahmed Mohammed Mahbubul Islam Kamrul Laila Manik Kumar Talukder 《Open Journal of Rheumatology and Autoimmune Diseases》 2024年第2期60-68,共9页
Background: Juvenile Idiopathic Arthritis (JIA) is the most prevalent rheumatic disease in children. It is associated with abnormal levels of serum zinc (Zn) and copper (Cu) as during inflammation serum copper concent... Background: Juvenile Idiopathic Arthritis (JIA) is the most prevalent rheumatic disease in children. It is associated with abnormal levels of serum zinc (Zn) and copper (Cu) as during inflammation serum copper concentration increases and zinc decreases. Objective: To assess the serum Zn and Cu levels in different sub-types of JIA patients and their correlation with the disease duration. Methods: This cross-sectional study was conducted over twelve months at the Pediatric Rheumatology Division, Department of Paediatrics, Bangabandhu Sheikh Mujib Medical University. Sixty-nine JIA cases that fulfilled the International League of Association for Rheumatology (ILAR) criteria were taken as cases and age and sex-matched healthy children were considered as controls. The serum Zn and Cu tests were done using the spectrophotometric method with INDIKO PLUS Drug Analyzer. Data were recorded in a pre-designed questionnaire. Data were checked, verified and analyzed manually where continuous variables were analyzed using unpaired t-test and categorical variables using the ANOVA test. Pearson’s correlation coefficient test was used to see the correlation of serum zinc and copper levels with disease duration. Results: Boys were predominant in both case and control groups, with the majority within the 10 to 16-year-age group. Enthesitis-related arthritis (ERA) was the most common subtype followed by sJIA, Oligo JIA, Poly JIA (RF-) and unclassified subtypes. Disease duration was found less than 12 months in 30.4% of JIA patients. Serum analysis revealed a statistically significant reduction in mean zinc levels and increased copper levels in JIA patients compared to controls. This study observed a negative correlation between serum zinc levels and disease duration, whereas serum copper levels exhibited a positive correlation with disease duration. Conclusion: In conclusion, this study revealed that JIA patients exhibit alterations in serum zinc and copper levels. Serum copper levels showed a positive correlation and serum zinc levels showed a negative correlation with the duration of the disease. 展开更多
关键词 copper Juvenile Idiopathic Arthritis ZINC
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Preliminary Investigation of Copper(II) Ion Binding or Complex Coordination in Lysozeme Molecules
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作者 Kou Takahashi Ryotaro Miyazaki +2 位作者 Daisuke Nakane Temitayo O. Aiyelabola Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 2024年第4期98-103,共6页
Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed... Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed amino acid derivative Schiff base copper(II) complexes were obtained. Herein we discuss primarily on the binding mode of copper(II) of the complexes obtained with egg white lysozyme. The electron density of copper(II) ions was confirmed by X-ray crystal structure analysis. The Val derivative Schiff base copper(II) complex was weakly bound at Arg114 of egg white lysozyme. In other copper(II) complexes, binding of copper(II) ions with dissociated ligands to various residues was observed. The binding sites of copper(II) ions were compared with computational scientific predictions. 展开更多
关键词 copper Schiff Base LYSOZYME Metal-Protein Binding Computational Methods
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Study of the Effect of Acetic Acid and Phosphate on Copper Corrosion by Immersion Tests
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作者 Yuna Yamaguchi Kaho Sugiura +4 位作者 Toyohiro Arima Fuka Takahashi Itaru Ikeda Yutaka Yamada Osamu Sakurada 《Materials Sciences and Applications》 2024年第1期15-23,共9页
It was reported that hemispheric corrosion occurred in copper tubes in an acetic acid environment. When hemispheric corrosion occurred, corrosion could easily progress if water then flowed into the copper pipe, and co... It was reported that hemispheric corrosion occurred in copper tubes in an acetic acid environment. When hemispheric corrosion occurred, corrosion could easily progress if water then flowed into the copper pipe, and countermeasures were needed. Therefore, we studied the copper corrosion caused by acetic acid. The present work investigated the relationship between the corrosion form of copper and acetic acid concentration using phosphorous-deoxidized copper, and reported that hemispherical corrosion was observed at acetic acid concentrations of 0.01 to 1 vol.% (0.002 to 0.2 mol·L<sup>-1</sup>) in the immersion test. In this study, the effects of acetic acid and phosphate on copper corrosion were examined using oxygen-free copper in immersion tests. The results suggested that different concentrations of phosphate in acetic acid solutions and the presence or absence of acetic acid and phosphate affected the corrosion of copper, resulting in different corrosion forms and corrosion progress. 展开更多
关键词 Acetic Acid PHOSPHATE Oxygen-Free copper Hemispherical Corrosion Ant-Nest Corrosion
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铜渣贫化回收铜的研究现状及展望 被引量:1
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作者 迟晓鹏 刘浩宇 +2 位作者 夏俊 翁威 衷水平 《金属矿山》 CAS 北大核心 2024年第1期293-303,共11页
铜是现代工业不可或缺的原材料,然而我国铜资源对外依存度高,是典型的“卡脖子”资源。铜主要通过火法冶炼铜精矿制得,冶炼过程渣量大、渣含铜量高达0.5%~5%,远高于我国铜矿的可采品位(0.2%)。因此,研究铜渣贫化回收铜的工艺对提升我国... 铜是现代工业不可或缺的原材料,然而我国铜资源对外依存度高,是典型的“卡脖子”资源。铜主要通过火法冶炼铜精矿制得,冶炼过程渣量大、渣含铜量高达0.5%~5%,远高于我国铜矿的可采品位(0.2%)。因此,研究铜渣贫化回收铜的工艺对提升我国资源保障能力具有重要意义。基于铜/铜锍在渣中的赋存状态、铜损的主要形式,重点综述了现阶段铜渣贫化回收铜的工艺技术,包括火法贫化法、浮选法、湿法处理等,并对未来的研究重点进行了展望。目前,电炉贫化处理量大,技术成熟,但其通常使用煤炭等作为还原剂,由于其密度小于铜渣,反应时大多漂浮渣层表面并燃烧,反应不充分,也不利于大气环保。另外,工业上常使用金属铁棒还原炉底结瘤的磁铁矿,但其密度大于铜/铜锍,在渣液中沉降速度快,对渣层的还原不彻底。因此,开发环保、高效的还原剂逐渐成为火法电炉贫化研究的重点。浮选法是处理天然铜矿的常用手段,但铜渣存在硬度高、伴生关系复杂、粒度分布不均、微细粒多等浮选难点,同时铜渣高温浮选导致捕收剂失活的问题也亟待解决。在处理低品位铜渣时,湿法浸出是常用手段,但化学试剂和废液环保问题难以解决;生物浸出具有性质稳定、对环境无污染,且浸出后金属含量较低等优点,但其浸出周期长、效率低。根据目前贫化工艺的难点,对未来贫化工艺开发与优化进行了展望,如增加外场聚集四氧化三铁以改善铜/铜锍沉降环境、开发环保高效的火法贫化还原剂、探究还原剂对不同铜渣渣型的作用机制以及开发耐高温的铜渣浮选新药剂等。 展开更多
关键词 铜渣 渣含铜 还原贫化 还原剂 冰铜
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基于土柱模拟降雨对铜尾矿重金属淋溶进入下伏土壤的生态风险研究 被引量:1
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作者 贺婧 金安妮 +4 位作者 张扣扣 马娟 罗玲玲 任惠芹 钟艳霞 《河南师范大学学报(自然科学版)》 CAS 北大核心 2024年第3期119-130,共12页
为探究铜尾矿重金属释放对环境的影响,通过动态淋溶实验,配置初始pH=7.2的人工模拟雨水为淋滤液,采用柱状淋溶装置进行尾矿重金属淋出实验,探究中卫某铜尾矿重金属的淋溶释放特征,评估尾矿重金属淋溶的生态风险.结果表明,尾矿中Cu、Zn... 为探究铜尾矿重金属释放对环境的影响,通过动态淋溶实验,配置初始pH=7.2的人工模拟雨水为淋滤液,采用柱状淋溶装置进行尾矿重金属淋出实验,探究中卫某铜尾矿重金属的淋溶释放特征,评估尾矿重金属淋溶的生态风险.结果表明,尾矿中Cu、Zn、As、Cd和Pb平均质量含量分别为2130.30、105.10、234.41、0.72和64.57mg·kg^(-1),均超出宁夏土壤重金属元素背景值.淋溶10次后,尾矿中Cd、Zn、Pb、As、Cu等重金属的释放率分别为1.98%、0.32%、0.30%、0.15%、0.01%,即Cd的释放率最高.淋溶后,尾矿重金属质量含量明显下降,其中0~5cm深度尾矿重金属含量下降最多,As的释放量最大,重金属向下层迁移明显.尾矿中Cu、Pb、Cd和Zn主要淋失碳酸盐结合态,As主要淋失可交换态,As和Cd的淋溶风险较高.Cu是尾矿重金属中关键的生态风险因子,尾矿中Cd和Cu为高风险,As、Zn和Pb为中风险. 展开更多
关键词 铜尾矿 重金属淋溶 生态风险
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碳氢树脂高频覆铜板的研究进展 被引量:1
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作者 李会录 夏婷 +1 位作者 苏建锋 李颖 《绝缘材料》 CAS 北大核心 2024年第1期1-8,共8页
本文综述了高频覆铜板的特点,并对其基体树脂的介电性能进行对比,重点介绍了碳氢树脂(PCH)高频覆铜板的研究进展。通过对目前碳氢树脂高频覆铜板研究的总结,找出现存的问题并对其未来发展趋势进行展望。
关键词 高频 碳氢树脂 低介电 覆铜板
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Coordination and Photoisomerization of Azobenzene-Amino Acid Schiff Base Copper(II) Complexes to Lysozyme
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作者 Yuto Kuroda Ryotaro Miyazaki +2 位作者 Daiki Shimonishi Daisuke Nakane Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第3期34-44,共11页
In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a we... In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a well-known protein, to change ligand conformation under binding to lysozyme. Among several spectroscopic investigations, ESR clearly showed that the nitrogen atom of the amino acid residue of lysozyme was bound to the paramagnetic copper(II) ion of the complex, and UV light irradiation confirmed photoisomerization of the azobenzene moiety of the ligand to cis-form. The binding mode was considered by means of spectroscopic as well as computational methods, whereas complete crystallographic verification was still a preliminary stage. 展开更多
关键词 AZOBENZENE Schiff Base copper Amino Acid LYSOZYME Artificial Metalloprotein
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2023年中国铜工业供需形势分析 被引量:3
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作者 张楠 《中国矿业》 北大核心 2024年第2期20-28,共9页
2023年,国际形势日趋复杂,全球经济变化、地缘政治危机和逆全球化思维都对全球铜工业发展格局产生了较大影响。在此背景下,由于新能源、新技术等高速发展的新兴产业的带动,全球铜工业仍保持了平稳运行,精炼铜生产与消费都保持了较好的... 2023年,国际形势日趋复杂,全球经济变化、地缘政治危机和逆全球化思维都对全球铜工业发展格局产生了较大影响。在此背景下,由于新能源、新技术等高速发展的新兴产业的带动,全球铜工业仍保持了平稳运行,精炼铜生产与消费都保持了较好的增长态势,中国铜工业面对复杂严峻的国际形势和艰巨繁重的国内改革发展稳定任务,也保持了稳中有升的运行态势。2023年,中国铜工业在生产方面保持了平稳增长,精炼铜产量增速超过两位数;企业经济效益也由降转升,全年规模以上企业营收与利润双双增长;铜冶炼回收率和综合能耗等生产技术指标不断向好;产业结构进一步优化,铜冶炼产能在区位优势的带动下布局越发分散,铜加工产能布局则高度集中在龙头区域;固定资产投资保持快速增长,但主要集中在下游领域;下游消费方面,精炼铜消费增速好于预期,从消费领域看呈现明显分化,电源和电网工程完成投资进度加快,交通运输领域乘用车产销量保持较快增长,但房地产和电子信息行业则表现疲软;贸易方面,铜原料进口和下游产品出口都保持增长态势,特别是铜原料进口方面,合计进口铜金属量远超历年。中国铜工业经过二十年的高速发展,已经成为全球第一大铜生产国与铜消费国,拥有完整的产业链条和先进的生产工艺技术,但中国铜工业在产业结构上仍存在着突出问题:原料供应以进口为主的局面短期内难以改变,原料对外依存度不断攀升;铜冶炼产能持续扩张,原料供应紧张,加工费下行风险加大;缺乏大型国际化矿业公司,企业在盈利能力和话语权上表现较弱。聚焦存在的问题与风险,中国铜工业如何适应当前国际国内形势,保障原材料供应安全和铜工业强国建设,是当前铜工业面临的最重要问题。建议继续深入开展铜工业供给侧结构性改革;多种方式夯实资源基础,提高资源保障程度;强化产业间协同、绿色、循环发展;加强新技术研发与推广,推动铜工业高质量发展。 展开更多
关键词 铜工业 资源供应 产业结构 消费 投资 形势分析
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Wear Evaluation of Copper-Nickel-Aluminum Alloys under Extreme Conditions
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作者 Rene Guardian Isai Rosales-Cadena +1 位作者 Constancio Diaz-Reyes Juan Antonio Ruiz-Ochoa 《Journal of Minerals and Materials Characterization and Engineering》 CAS 2023年第1期16-26,共11页
Cu-Ni-Al alloys at different concentrations were obtained using a high frequency induction melting unit, keeping a balance in the nominal compositions. Light alloys are important to be used in industrial applications.... Cu-Ni-Al alloys at different concentrations were obtained using a high frequency induction melting unit, keeping a balance in the nominal compositions. Light alloys are important to be used in industrial applications. Aluminum additions result in a positive hardness increment of the ternary alloys in comparison with the binary Cu-Ni alloys. Generalized wear mechanisms of the alloys with low aluminum content are basically type abrasive, while samples with 5 and 10 at.% Al present an oxidative-adhesive wear mechanism. Wear results have indicated that aluminum addition affects positively the wear resistance, mainly in samples with high aluminum content product of the creation during the test of different oxides corresponding to the elements present in the alloys. 展开更多
关键词 copper Nickel Alloys HARDNESS Mechanical Properties Heat Treatment
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Regional Copper Deficiency in White-Tailed Deer
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作者 Seth T. Rankins Randy W. DeYoung +6 位作者 Aaron M. Foley Alfonso Ortega-S. Timothy E. Fulbright David G. Hewitt Clayton D. Hilton Landon R. Schofield Tyler A. Campbell 《Open Journal of Ecology》 2023年第1期9-21,共13页
Minerals are critical in maintaining health and physiological function in wildlife. Geographic variation in soil and forage mineral concentration may predispose wildlife to mineral imbalances, where a common symptom i... Minerals are critical in maintaining health and physiological function in wildlife. Geographic variation in soil and forage mineral concentration may predispose wildlife to mineral imbalances, where a common symptom is restricted somatic growth. We investigated if mineral imbalances could explain localized differences in morphology of white-tailed deer (Odocoileus virginianus) occurring in geographically proximate sites with similar management, climate, and habitat. We collected serum samples and morphological measurements from free-ranging white-tailed deer captured during 2011-2019 from coastal and inland rangeland sites in South Texas, USA. We measured mineral concentrations in serum from captured deer at each location. Asymptotic deer body mass and antler size averaged 8% - 20% smaller for deer at the coastal compared to the inland site. The proportion of deer with deficient levels of serum copper was greater at the coastal site (66% versus 14%). Our results suggest regional mineral deficiencies in deer may limit antler and body development. Wildlife managers should be aware of all aspects of wildlife nutrition and the importance of considering nutrients beyond energy and protein. 展开更多
关键词 copper MINERALS NUTRITION UNGULATES SERUM White-Tailed Deer
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Exciting News from Indentations onto Silicon, Copper, and Tungsten
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作者 Gerd Kaupp 《Journal of Applied Mathematics and Physics》 2023年第12期4042-4078,共37页
Indentations onto crystalline silicon and copper with various indenter geometries, loading forces at room temperature belong to the widest interests in the field, because of the physical detection of structural phase ... Indentations onto crystalline silicon and copper with various indenter geometries, loading forces at room temperature belong to the widest interests in the field, because of the physical detection of structural phase transitions. By using the mathematically deduced F<sub>N</sub>h<sup>3/2 </sup>relation for conical and pyramidal indentations we have a toolbox for deciding between faked and experimental loading curves. Four printed silicon indentation loading curves (labelled with 292 K, 260 K, 240 K and 210 K) proved to be faked and not experimental. This is problematic for the AI (artificial intelligence) that will probably not be able to sort faked data out by itself but must be told to do so. High risks arise, when published faked indentation reports remain unidentified and unreported for the mechanics engineers by reading, or via AI. For example, when AI recommends a faked quality such as “no phase changes” of a technical material that is therefore used, it might break down due to an actually present low force, low transition energy phase-change. This paper thus installed a tool box for the distinction of experimental and faked loading curves of indentations. We found experimental and faked loading curves of the same research group with overall 14 authoring co-workers in three publications where valid and faked ones were next to each other and I can thus only report on the experimental ones. The comparison of Si and Cu with W at 20-fold higher physical hardness shows its enormous influence to the energies of phase transition and of their transition energies. Thus, the commonly preferred ISO14577-ASTM hardness values HISO (these violate the energy law and are simulated!) leads to almost blind characterization and use of mechanically stressed technical materials (e.g. airplanes, windmills, bridges, etc). The reasons are carefully detected and reported to disprove that the coincidence or very close coincidence of all of the published loading curves from 150 K to 298 K are constructed but not experimental. A tool-box for distinction of experimental from faked indentation loading curves (simulations must be indicated) is established in view of protecting the AI from faked data, which it might not be able by itself to sort them out, so that technical materials with wrongly attributed mechanical properties might lead to catastrophic accidents such as all of us know of. There is also the risk that false theories might lead to discourage the design of important research projects or for not getting them granted. This might for example hamper or ill-fame new low temperature indentation projects. The various hints for identifying faked claims are thus presented in great detail. The low-temperature instrumental indentations onto silicon have been faked in two consecutive publications and their reporting in the third one, so that these are not available for the calculation of activation energies. Conversely, the same research group published an indentation loading curve of copper as taken at 150 K that could be tested for its validity with the therefore created tools of validity tests. The physical algebraic calculations provided the epochal detection of two highly exothermic phase transitions of copper that created two polymorphs with negative standard energy content. This is world-wide the second case and the first one far above the 77 K of liquid nitrogen. Its existence poses completely new thoughts for physics chemistry and perhaps techniques but all of them are open and unprepared for our comprehension. The first chemical reactions might be in-situ photolysis and the phase transitions can be calculated from experimental curves. But several further reported low temperature indentation loading curves of silicon were tested for their experimental reality. And the results are compared to new analyses with genuine room temperature results. A lot is to be learned from the differences at room and low temperature. 展开更多
关键词 Phase-Transition-Onset and -Energy Indentation of Silicone copper copper Nanoparticles Tungsten with Polymorphs Low-Temperature Indentations Detection of Faked Loading Curves Protection of AI from False Advices Risk of Catastrophic Crashes Physical Hardness Exothermic copper-Transitions Algebraic Calculations Negative-Standard-Energy Polymorphs
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Modelling and Optimisation of Copper Adsorption in Solution by the Response Surface Method
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作者 Kalidou Ba Alpha Ousmane Toure +2 位作者 Samba Ndiaye Moussa Diop Falilou Mbacke Sambe 《Advances in Chemical Engineering and Science》 CAS 2023年第1期36-49,共14页
Copper is considered a heavy metal that can be toxic at certain concentrations and its presence in water is a potential threat to public health. These heavy metals also contribute to a remarkable degradation of the en... Copper is considered a heavy metal that can be toxic at certain concentrations and its presence in water is a potential threat to public health. These heavy metals also contribute to a remarkable degradation of the environment, hence the need for effective treatment methods to remove them. In this study, a mixture of titaniferous sand and calcium silicate was used as adsorbent material to eliminate copper in solution. The calcium silicate was synthesised from fluosilicic acid, which is a by-product of phosphoric acid manufacture. The titaniferous sand is a residue from a mining industry. Both adsorbents were characterised by infrared spectroscopy and X-ray fluorescence to determine their compositions and physicochemical properties. The response surfaces, through the Box-Behnken model, were used to model and optimise various adsorption parameters, namely initial copper concentration (A: 60 - 200 mg/L), adsorbent dose (B: 0.1 - 0.6 g) and pH (C: 4 - 10). The copper removal efficiency (98.92%), after statistical analysis, was obtained under the following optimal conditions: an adsorbent dose of 0.55 g, an initial copper concentration of 197.25 mg/L and a pH of 9.85. The study of the effects of the operating parameters showed that they had a positive effect on the copper removal efficiency. 展开更多
关键词 ADSORPTION Calcium Silicate copper Response Surface Titaniferous Sand
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Geology of the Copper Mineralization in Proterozoic Ajabgarh Meta-Sediments of, Dokan-Dariba Belt, Sikar District Rajasthan Northwestern India
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作者 Rajendra Kumar Sharma 《Open Journal of Geology》 CAS 2023年第5期384-430,共47页
The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin A... The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin Alwar-Ajabgarh sub basin exposes that a thick sequence of Ajabgarh group of rocks overlies a thick arenaceous sequence of Alwar group of Delhi Super Group of rocks. The Ajabgarh meta sediments here in the Neem Ka thana area are characterized by presence of Bornite dominated copper mineralization with silver association and minor presence of Pb. The mineralization has been described by various workers as strata-bound, hypogene and IOCG. But these inferences are based on part information and the inference drawn is sectorial in nature. The current study includes a holistic study based on exploration over a period of more than two decades and the data generated suggest thereof, that this syngenetic sulphide mineralization associated with the sedimentation of marl and carbonate rocks. Subsequently it has been relocated during 2<sup>nd</sup> deformation accompanied by epigenetic component of mineralization depicted in terms of vein filled coarse grained aggregates of bornite and chalcopyrite disposed across the general disposition of litho-package. The EPMA and fluid inclusion data generated from the area indicate association of typical hydrothermal environment minerals like, Perkrite, Wittchenite, Aguilarite, Molybdnite etc. The mineralizing fluids have been trapped between the temperature ranges of 130°C to 375°C with average being 250°C to 300°C. The fluid salinity also varies from near pure hot water to moderately saline fluid indicative of multi-episodic mineralization of syngenetic nature coupled with epigenetic component. The ore textures indicate 500°C temperature range;certain intergrowths of minerals like specular hematite and bornite suggest the occurrence of hypogene environment induced due to emplacement of granite/pegmatite on the eastern and southern margins of the belt. The strata bound nature suggests the euxogenic environment facilitated by carbonate facies of rocks. The parallelism of sulphide with the rock fabric was attained during first deformation and the epigenetic component coupled with the hypogene assemblage was deposited during the D<sub>2</sub> deformation in the brittle ductile shear zones and limb shears, between the temperature ranges of 130°C to 570°C as deduced from petrochemical data. Hence a comprehensive model is suggested here on evolution of process of mineralization in the Neem Ka Thana belt. 展开更多
关键词 Proterozoic copper Mineralization Ajabgarh Meta Sediments Dariba-Dokan Belt Neemka Thana. Northwestern India
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Research Progress of Nano Copper Azide
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作者 Runpeng Jiang Zhenzhan Yan 《Journal of Materials Science and Chemical Engineering》 2023年第7期104-113,共10页
The development trend of miniaturization, chipization, integration, and intelligence of new energetic devices has put forward higher requirements for primary explosives, and the toxicity of lead-containing initiating ... The development trend of miniaturization, chipization, integration, and intelligence of new energetic devices has put forward higher requirements for primary explosives, and the toxicity of lead-containing initiating explosives has also caused increasing concerns. Nano copper azide, due to its green and high-energy characteristics, has attracted increasing interest from researchers in recent years. The research progress of Nano copper azide energetic materials is summarized from the design and preparation of composite energetic materials, and the analysis of sensitivity changes. On this basis, the key points to realize its application prospects are discussed: Develop the preparation method of carbon material modification and the combination of processing and forming to prepare new composite materials to make up for their overly sensitive defects, while giving full play to their advantages of high energy density. By comparing the existing research progress of Nano copper azide, we can understand its performance parameters more systematically, and guide the further application of Nano copper azide. . 展开更多
关键词 Nano copper Azide Energetic Material Primary Explosives
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Copper Mineralization in the Lower Cambrian Cover of Jbel N’Zourk (Central Anti Atlas, Morocco): Tectonic-Mineralizations Relationships
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作者 Achraf Ait Yazza Ismail Bouskri +2 位作者 Mohamed Raji Faouziya Haissen Noura Zoraa 《Open Journal of Geology》 2023年第11期1195-1219,共25页
The Moroccan Anti-Atlas is a vast geological region composed of a Precambrian basement covered by a late-Neoproterozoic to Paleozoic sedimentary sequences. More than 200 copper occurrences are listed in these sequence... The Moroccan Anti-Atlas is a vast geological region composed of a Precambrian basement covered by a late-Neoproterozoic to Paleozoic sedimentary sequences. More than 200 copper occurrences are listed in these sequences. The copper mineralization of the Jbel N’Zourk (Central Anti-Atlas) is observed into the lower Limestones of the lower Cambrian (Adoudou formation), just above the volcanic formations of the Jbel Boho between Bou Azzer El Graara and Zenaga inliers. The region is by an E-W shortening resulting in an overlapping structure with vergence associated with folds. Generally, the mineralization is hosted along the principal fault of Jbel N’Zourk and sometimes in the anticlines hinges. The petrographic study showed that the mineralization can be observed in several aspects, either in the fractures and veins, in small karsts or rarely disseminated in calcite and dolomite minerals. These observations host new arguments who contribute to a later reconcentration of the copper mineralization of Jbel N’Zourk, trapped on faulted and folded structures attributed to Variscan deformation. 展开更多
关键词 Central Anti-Atlas Lower Cambrian Cover copper Mineralization Structural
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铜尾矿改性水泥基地聚合物注浆材料性能与机理分析 被引量:1
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作者 付宏渊 姚杰 邱祥 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期1107-1119,共13页
为促进岩土工程绿色发展,提高尾矿资源化利用效率,选取铜尾矿制备铜尾矿改性水泥基地聚合物注浆材料,研究水固比、铜尾矿掺量、碱激发剂用量及碱激发剂模数对改性浆液各性能指标的影响规律及微观机理。研究结果表明:掺入尾矿有利于改善... 为促进岩土工程绿色发展,提高尾矿资源化利用效率,选取铜尾矿制备铜尾矿改性水泥基地聚合物注浆材料,研究水固比、铜尾矿掺量、碱激发剂用量及碱激发剂模数对改性浆液各性能指标的影响规律及微观机理。研究结果表明:掺入尾矿有利于改善改性浆液力学性能,掺入碱激发剂能提高改性浆液整体的反应程度,减小改性浆液析水率;综合考虑各项性能指标,选取改性浆液最佳配比,即水固比为1.0,铜尾矿掺量为30%(质量分数,下同),碱激发剂用量为4%,碱激发剂模数为1.6;相较于纯水泥浆液,改性浆液最佳配比黏度减小11.1%,流动度增大22.3%,析水率减小29.7%,28 d结石体抗压强度仅减小9.5%,耐久性能良好;改性浆液发生地聚合物反应形成了具有三维空间网状结构的C-A-S-H凝胶和N-A-S-H凝胶等胶凝物质。本研究成果可为岩土工程提供高性能低成本的注浆材料,同时还将为尾矿等固废材料资源化利用提供参考。 展开更多
关键词 岩土工程 注浆材料 铜尾矿 地聚合物 碱激发 微观机理
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某铜矿工艺矿物学研究 被引量:1
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作者 匡文龙 张跃权 +7 位作者 张志辉 申滔 杨铖 陈健龙 吴荔 刘尧奇 刘兆阳 黄英剑 《有色金属(选矿部分)》 CAS 2024年第6期21-31,共11页
为了充分了解某铜矿矿石性质,制定合理的选矿工艺流程,利用化学多元素分析、光学显微镜、MLA等综合手段,对矿石的化学成分、矿物种类、结构构造、主要矿物的嵌布特征以及主要有用元素的赋存状态进行分析研究。查明该矿石中主要有用元素... 为了充分了解某铜矿矿石性质,制定合理的选矿工艺流程,利用化学多元素分析、光学显微镜、MLA等综合手段,对矿石的化学成分、矿物种类、结构构造、主要矿物的嵌布特征以及主要有用元素的赋存状态进行分析研究。查明该矿石中主要有用元素为Cu和S,品位分别为1.73%、20.81%,伴生贵金属元素Au和Ag,品位分别为0.63、5.46 g/t。铜矿物主要是黄铜矿,其次是砷黝铜矿、黝铜矿,铜矿物以0.020~0.147 mm细粒为主,主要嵌布在硫化物及脉石矿物中。金属硫化物主要以黄铁矿为主,嵌布粒度以0.043~0.417 mm为主,在选矿时需要细磨以实现单体解离。金矿物主要以自然金和银金矿为主,以微粒金为主,嵌布在硫化物及脉石矿物中,共生关系复杂,回收难度也比较大。银元素分布比较分散,大部分分布在黄铁矿和铜矿物中。根据以上结果,建议采用“铜硫混合浮选-铜硫分离浮选工艺流程”处理铜矿石,对混合铜硫精矿再磨后进行分离,金银可以分别在铜精矿、硫精矿和尾矿中计价回收。 展开更多
关键词 铜矿 工艺矿物学 赋存状态 嵌布特征
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铝粉还原污酸中砷新工艺研究 被引量:1
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作者 王永辉 李晓恒 +2 位作者 崔育涛 田静 王亭圆 《中国有色冶金》 CAS 北大核心 2024年第3期95-100,共6页
由于硫化精矿中砷含量越来越高,致使烟气处理过程产生的污酸中砷含量也越来越高,同时污酸中含有铜、铁等有价金属。目前污酸除砷方法多以除砷为目的,形成的含砷渣属于危废,还需要二次处理。本研究研发了还原除砷新工艺,首先向污酸中加... 由于硫化精矿中砷含量越来越高,致使烟气处理过程产生的污酸中砷含量也越来越高,同时污酸中含有铜、铁等有价金属。目前污酸除砷方法多以除砷为目的,形成的含砷渣属于危废,还需要二次处理。本研究研发了还原除砷新工艺,首先向污酸中加入硫化砷渣进行脱铜预处理并回收铜,然后用铝粉还原脱铜后液中的砷回收砷,最后向脱砷液中加入硫酸钾回收铝,还原后液回收还原剂后采用两段中和法处理。试验研究结果表明,在加入铜离子摩尔量1.1倍的硫化砷渣、反应温度85℃、反应时间3 h的条件下,污酸中的铜含量由2000 mg/L降至196 mg/L,硫化铜渣返熔炼配料系统;在还原温度70℃、还原时间2 h,还原剂用量1.8倍的条件下,砷的还原率大于96%,还原后液中的砷含量低于300 mg/L,得到的砷渣品位大于95%,可用于后续制备高品位单质砷;在硫酸钾用量1.1倍、反应温度常温、反应时间2 h的条件下,溶液含铝3.6 g/L,得到的明矾可达到《工业硫酸铝钾》(HG/T2565—2007)一等品标准。该方法除砷效果好,且能将污酸中的砷转变为具有经济价值的砷产品,还不会产生硫化氢气体,具有应用推广价值。 展开更多
关键词 铜冶炼 污酸 除砷 铝粉还原 含砷渣 单质砷 脱铜 沉铝
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铜调节的细胞死亡相关基因与前列腺癌关系分析 被引量:1
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作者 李伟 程丰 +1 位作者 朱俊雷 王锁刚 《现代泌尿外科杂志》 2024年第1期46-50,68,共6页
目的基于美国癌症肿瘤基因图谱(the cancer genome atlas,TCGA)数据库分析铜调节的细胞死亡相关基因与前列腺癌患者预后和免疫细胞浸润的关系。方法从TCGA数据库下载所有前列腺癌患者的基因数据,其中包括前列腺癌组织501例,正常组织52... 目的基于美国癌症肿瘤基因图谱(the cancer genome atlas,TCGA)数据库分析铜调节的细胞死亡相关基因与前列腺癌患者预后和免疫细胞浸润的关系。方法从TCGA数据库下载所有前列腺癌患者的基因数据,其中包括前列腺癌组织501例,正常组织52例。运用R软件提取前列腺癌患者中铜调节的细胞死亡相关基因表达矩阵,进行差异分析、多因素回归分析筛选出预后基因,对预后基因进行生存分析,同时探讨预后相关基因与免疫细胞之间的相关性。结果甘氨酸裂解系统蛋白H(GCSH)与前列腺癌患者的预后显著相关,同时发现其与前列腺癌患者中的树突细胞、CD8^(+)T细胞、浆细胞也显著相关(P<0.05)。结论GCSH基因在前列腺癌的发生、发展中起重要作用,有望成为前列腺癌预后的标志物。 展开更多
关键词 前列腺癌 铜调节的细胞死亡 肿瘤微环境 甘氨酸裂解系统蛋白H 美国癌症肿瘤基因图谱数据库 标志物
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As和MgO的加入对铜冶炼渣中砷玻璃化的影响
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作者 金哲男 王保仁 +2 位作者 杨洪英 赵前飞 符岩 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第6期2020-2033,共14页
研究FeO−SiO_(2)−Fe_(2)O_(3)−B_(2)O_(3)−CaO−Al_(2)O_(3)−(MgO)体系铜冶炼渣中砷(As)的玻璃化。通过XRD、SEM、FTIR和XPS分析手段系统地研究As玻璃化机制。结果表明,As与铁硅酸盐炉渣表现出良好的相容性。FTIR和XPS分析结果表明,As可... 研究FeO−SiO_(2)−Fe_(2)O_(3)−B_(2)O_(3)−CaO−Al_(2)O_(3)−(MgO)体系铜冶炼渣中砷(As)的玻璃化。通过XRD、SEM、FTIR和XPS分析手段系统地研究As玻璃化机制。结果表明,As与铁硅酸盐炉渣表现出良好的相容性。FTIR和XPS分析结果表明,As可以部分替代硅形成Si—O—As结构,从而提高熔体的聚合度。[BO_(3)]^(3−)结构单元随着As含量的增加而趋于减少,而加入MgO后则观察到相反的行为。此外,MgO增加了熔体的非桥氧数量(NBO)。TCLP、SPLP和pH依赖性测试结果表明,As的浸出毒性随着As含量的增加而增加,但随着MgO的加入而降低。DSC分析结果表明,As和MgO的加入均可以改善含As玻璃的热稳定性。 展开更多
关键词 玻璃化 氧化镁 铜冶炼渣 炉渣结构
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