期刊文献+
共找到51,015篇文章
< 1 2 250 >
每页显示 20 50 100
Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases 被引量:2
1
作者 Xiao-xia BAN Hao WAN +7 位作者 Xin-xing WAN Ya-ting TAN Xi-min HU Hong-xia BAN Xin-yu CHEN Kun HUANG Qi ZHANG Kun XIONG 《Current Medical Science》 SCIE CAS 2024年第1期28-50,共23页
Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess ca... Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess can adversely affect cellular function.Therefore,copper homeostasis is stringently regulated.Recent studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular copper.Cuproptosis induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster proteins.In neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper homeostasis.This review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative diseases.This offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis. 展开更多
关键词 cuproptosis copper metabolism copper homeostasis NEURODEGENERATION neurodegenerativedisease
下载PDF
Design of low-alloying and high-performance solid solution-strengthened copper alloys with element substitution for sustainable development 被引量:1
2
作者 Jiaqiang Li Hongtao Zhang +2 位作者 Jingtai Sun Huadong Fu Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期826-832,共7页
Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-... Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-speed rail contact wires,electronic component connectors,and other devices.Overcoming the contradiction between low alloying and high performance is an important challenge in the development of solid solution-strengthened copper alloys.Taking the typical solid solution-strengthened alloy Cu-4Zn-1Sn as the research object,we proposed using the element In to replace Zn and Sn to achieve low alloying in this work.Two new alloys,Cu-1.5Zn-1Sn-0.4In and Cu-1.5Zn-0.9Sn-0.6In,were designed and prepared.The total weight percentage content of alloying elements decreased by 43%and 41%,respectively,while the product of ultimate tensile strength(UTS)and electrical conductivity(EC)of the annealed state increased by 14%and 15%.After cold rolling with a 90%reduction,the UTS of the two new alloys reached 576 and 627MPa,respectively,the EC was 44.9%IACS and 42.0%IACS,and the product of UTS and EC(UTS×EC)was 97%and 99%higher than that of the annealed state alloy.The dislocations proliferated greatly in cold-rolled alloys,and the strengthening effects of dislocations reached 332 and 356 MPa,respectively,which is the main reason for the considerable improvement in mechanical properties. 展开更多
关键词 element substitution copper alloy solid solution strengthening microstructure and performance
下载PDF
Editorial Commentary:Copper Homeostasis in Neurodegenerative Diseases
3
作者 Ying-hui LI Kun WANG 《Current Medical Science》 SCIE CAS 2024年第1期244-245,共2页
Copper,as an essential trace nutrient,plays a crucial role in biological processes such as mitochondrial respiration,antioxidant stress response,and the synthesis of biomolecules.Typically,cellular copper concentratio... Copper,as an essential trace nutrient,plays a crucial role in biological processes such as mitochondrial respiration,antioxidant stress response,and the synthesis of biomolecules.Typically,cellular copper concentrations are maintained at very low levels,a pattern also observed in cancer cells to prevent adverse consequences of copper overload,such as cuproptosis.This involves copper dependency,accumulation of lipidated proteins,and a reduction in Fe-S cluster proteins[1].Various neurodegenerative diseases are associated with imbalances in copper homeostasis. 展开更多
关键词 copper copper consequences
下载PDF
Detection of Al, Mg, Ca, and Zn in copper slag by LIBS combined with calibration curve and PLSR methods
4
作者 贾军伟 刘志峰 +1 位作者 潘从元 薛骅骎 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期132-138,共7页
The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was... The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was utilized for the spectral analysis of copper slag samples at a distance of 2.5 m. The composition of copper slag was then analyzed using both the calibration curve(CC) method and the partial least squares regression(PLSR) analysis method based on the characteristic spectral intensity ratio. The performance of the two analysis methods was gauged through the determination coefficient(R^(2)), average relative error(ARE), root mean square error of calibration(RMSEC), and root mean square error of prediction(RMSEP). The results demonstrate that the PLSR method significantly improved both R^(2) for the calibration and test sets while reducing ARE, RMSEC, and RMSEP by 50% compared to the CC method. The results suggest that the combination of LIBS and PLSR is a viable approach for effectively detecting the elemental concentration in copper slag and holds potential for online detection of the elemental composition of high-temperature molten copper slag. 展开更多
关键词 copper slag ELEMENT REMOTE LIBS PLSR
下载PDF
Interphase migration and enrichment of lead and zinc during copper slag depletion
5
作者 Jun HAO Zhi-he DOU +2 位作者 Xing-yuan WAN Ting-an ZHANG Kun WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3029-3041,共13页
An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was established.The occurrence of various components in copper slag was predicted using sulfur-oxygen potential calcula... An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was established.The occurrence of various components in copper slag was predicted using sulfur-oxygen potential calculations and confirmed through high-temperature experiments.The recovery rate of copper can reach 90.13%under the optimal conditions of 1200°C,an iron to silicon mass ratio of 1.0,3 wt.%ferrous sulfide,and a duration of 45 min.Lead(54.07 wt.%)and zinc(17.42 wt.%)are found in the flue dust as lead sulfate,lead sulfide,and zinc oxide,while copper matte contains lead(14.44 wt.%)and zinc sulfide(1.29 wt.%).The remaining lead and zinc are encapsulated as oxides within the fayalite phase. 展开更多
关键词 depletion LEAD copper slag STIRRING ZINC
下载PDF
Pyrolysis of Copper Phthalocyanine as Non-noble Metal Electrocatalysts for Oxygen Reduction Reaction
6
作者 ZHANG Lijuan LU Jinhua +1 位作者 WANG Yan LI Xiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1087-1092,共6页
We investigated the relationship between oxygen reduction reaction(ORR)activity and the pyrolysis temperature(650-850℃)of CuPc in alkaline solution.The highly active sites were formed through the decomposition of CuP... We investigated the relationship between oxygen reduction reaction(ORR)activity and the pyrolysis temperature(650-850℃)of CuPc in alkaline solution.The highly active sites were formed through the decomposition of CuPc or Cu-N_(4) structure after releasing 4-nitrophthalonitrile.Cu-Nx incorporated with carbon were the main active sites.The XPS measurement results show that,at lower temperature,the contents of pyridinic-N and pyrrolic-N account for the most of the total N.As the temperature is higher than 750℃,the content of graphitic N(26.11%)increases and pyridinic-N(58.81%)becomes the dominant specie.When the temperature is higher than 850℃,the content of graphitic N increases remarkably and becomes the dominant species.Moreover,the specific surface areas decrease with increased pyrolysis temperature.Benefiting from the synergistic effect,the pyrolysis temperature at 750℃of CuPc displays superior electrocatalytic properties.The obtained results reveal that the fabricated non-noble metal catalysts can be used as low-cost,efficient catalyst for water splitting ORR in metal-air batteries and fuel cells. 展开更多
关键词 copper phthalocyanine PYROLYSIS ELECTROCATALYTIC oxygen reduction reaction
下载PDF
Using Electrodeposition of Carboxylated Chitosan for Green Preparation of Copper Nanoclusters and Nanocomposite Films
7
作者 ZHANG Xiaoli LI Tingxue +4 位作者 WANG Qinghua YANG Yan ZHANG Chenyu LIU Yaning WANG Yifeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1348-1357,共10页
On the basis of coordinated electrodeposition of carboxylated chitosan(CCS),we presented a green method to prepare Cu NCs and Cu NCs/CCS nanocomposite films.The method shows a range of benefits,such as the convenient ... On the basis of coordinated electrodeposition of carboxylated chitosan(CCS),we presented a green method to prepare Cu NCs and Cu NCs/CCS nanocomposite films.The method shows a range of benefits,such as the convenient and eco-friendly process,mild conditions,and simple post-treatment.The experimental results reveal that a homogeneous deposited film(Cu NCs/CCS nanocomposite film)is generated on the Cu plate(the anode)after electrodeposition,which exhibits an obvious red florescence.The results from TEM observation suggest there are nanoparticles(with the average particle size of 2.3 nm)in the deposited film.Spectral analysis results both demonstrate the existence of Cu NCs in the deposited film.Moreover,the Cu NCs/CCS film modified electrode is directly created through electrodeposition of CCS,which enables promising application in the electrochemical sensing.By means of fluorescence properties of Cu NCs,the Cu NCs/CCS film also owns the potential in fluorescence detection.Therefore,this work builds a novel method for the green synthesis of Cu NCs,meanwhile it offers a convenient and new electrodeposition strategy to prepare polysaccharide-based Cu NCs nanocomposites for uses in functional nanocomposites and bioelectronic devices. 展开更多
关键词 nanocomposite films copper nanoclusters ELECTRODEPOSITION carboxylated chitosan POLYSACCHARIDES
下载PDF
Role of copper chelating agents: between old applications and new perspectives in neuroscience
8
作者 Rosalba Leuci Leonardo Brunetti +4 位作者 Vincenzo Tufarelli Marco Cerini Marco Paparella Nikola Puvača Luca Piemontese 《Neural Regeneration Research》 SCIE CAS 2025年第3期751-762,共12页
The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays a... The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays an important role in the central nervous system, where it is associated with glutamatergic signaling, and it is widely involved in inflammatory processes. Thus, diseases involving copper(Ⅱ) dyshomeostasis often have neurological symptoms, as exemplified by Alzheimer's and other diseases(such as Parkinson's and Wilson's diseases). Moreover, imbalanced copper ion concentrations have also been associated with diabetes and certain types of cancer, including glioma. In this paper, we propose a comprehensive overview of recent results that show the importance of these metal ions in several pathologies, mainly Alzheimer's disease, through the lens of the development and use of copper chelators as research compounds and potential therapeutics if included in multi-target hybrid drugs. Seeing how copper homeostasis is important for the well-being of animals as well as humans, we shortly describe the state of the art regarding the effects of copper and its chelators in agriculture, livestock rearing, and aquaculture, as ingredients for the formulation of feed supplements as well as to prevent the effects of pollution on animal productions. 展开更多
关键词 agriculture Alzheimer's disease CHELATORS copper feed supplements MULTI-TARGET
下载PDF
OsMYB84,a transcriptional regulator of OsCOPT2 and OsHMA5,modulates copper uptake and transport and yield production in rice
9
作者 Jingli Ding Chenchen Ji +6 位作者 Lu Yu Chuang Wang Guangda Ding Sheliang Wang Lei Shi Fangsen Xu Hongmei Cai 《The Crop Journal》 SCIE CSCD 2024年第2期456-469,共14页
Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator inv... Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator involved in uptake and transport of Cu via activation of OsCOPT2 and OsHMA expression.OsMYB84 was highly expressed in roots and anthers and induced by Cu.Overexpression of OsMYB84 promoted uptake and root-to-shoot translocation of Cu in rice,facilitated Cu distribution into grain and increased grain yield.In contrast,mutation of OsMYB84 reduced Cu concentration in xylem sap.OsMYB84 bound to the promoter region of OsCOPT2 and OsHMA5 and upregulated their expression.OsCOPT2 mutants showed reduced uptake of Cu and OsHMA5 overexpression lines showed increased root-to-shoot translocation of Cu. 展开更多
关键词 OsMYB84 OsCOPT2 OsHMA5 copper RICE
下载PDF
Purification of copper foils driven by single crystallization
10
作者 寇金宗 赵孟泽 +10 位作者 李兴光 何梦林 杨方友 刘科海 成庆秋 任云龙 刘灿 付莹 吴慕鸿 刘开辉 王恩哥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期506-511,共6页
High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current puri... High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards. 展开更多
关键词 PURIFICATION copper foil thermal annealing technique single crystallization
下载PDF
Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation
11
作者 Dong Ma Qinhui Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期43-53,共11页
The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by PG.However,the PG decomposition temperature remains high and the product yield remains... The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by PG.However,the PG decomposition temperature remains high and the product yield remains poor.By adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be improved.However,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic cost.Therefore,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same time.The effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting conditions.Finally,the reaction mechanism is proposed.It is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition temperature.For example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) yield.The process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed. 展开更多
关键词 PHOSPHOGYPSUM Sulfur dioxide copper slag FLUIDIZED-BED REDUCTION Waste treatment
下载PDF
A Multi-Stage Differential-Multifactorial Evolutionary Algorithm for Ingredient Optimization in the Copper Industry
12
作者 Xuerui Zhang Zhongyang Han Jun Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2135-2153,共19页
Ingredient optimization plays a pivotal role in the copper industry,for which it is closely related to the concentrate utilization rate,stability of furnace conditions,and the quality of copper production.To acquire a... Ingredient optimization plays a pivotal role in the copper industry,for which it is closely related to the concentrate utilization rate,stability of furnace conditions,and the quality of copper production.To acquire a practical ingredient plan,which should exhibit long duration time with sufficient utilization and feeding stability for real applications,an ingredient plan optimization model is proposed in this study to effectively guarantee continuous production and stable furnace conditions.To address the complex challenges posed by this integer programming model,including multiple coupling feeding stages,intricate constraints,and significant non-linearity,a multi-stage differential-multifactorial evolution algorithm is developed.In the proposed algorithm,the differential evolutionary(DE)algorithm is improved in three aspects to efficiently tackle challenges when optimizing the proposed model.First,unlike traditional time-consuming serial approaches,the multifactorial evolutionary algorithm is utilized to optimize multiple complex models contained in the population of evolutionary algorithm caused by the feeding stability in a parallel manner.Second,a repair algorithm is employed to adjust infeasible ingredient lists in a timely manner.In addition,a local search strategy taking feedback from the current optima and considering the different positions of global optimum is developed to avoiding premature convergence of the differential evolutionary algorithm.Finally,the simulation experiments considering different planning horizons using real data from the copper industry in China are conducted,which demonstrates the superiority of the proposed method on feeding duration and stability compared with other commonly deployed approaches.It is practically helpful for reducing material cost as well as increasing production profit for the copper industry. 展开更多
关键词 copper industry differential-multifactorial evolution ingredient optimization multi-stage optimization
下载PDF
Breaking the Fe_(3)O_(4)-wrapped copper microstructure to enhance copper-slag separation
13
作者 Xiaopeng Chi Haoyu Liu +4 位作者 Jun Xia Hang Chen Xiangtao Yu Wei Weng Shuiping Zhong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2312-2325,共14页
The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of c... The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of copper concentrates.Herein,the commercial powdery pyrite or anthracite is replaced with pyrite-anthracite pellets as the reductants to remove a large amount of Fe_(3)O_(4)particles in the molten slag,resulting in a deep fracture in the Fe_(3)O_(4)-wrapped copper microstructure and the full exposure of the copper matte cores.When 1wt%composite pellet is used as the reductant,the copper matte droplets are enlarged greatly from 25μm to a size observable by the naked eye,with the copper content being enriched remarkably from 1.2wt%to 4.5wt%.Density functional theory calculation results imply that the formation of the Fe_(3)O_(4)-wrapped copper structure is due to the preferential adhesion of Cu_(2)S on the Fe_(3)O_(4)particles.X-ray photoelectron spectroscopy,Fourier transform infrared spectrometer(FTIR),and Raman spectroscopy results all reveal that the high-efficiency conver-sion of Fe_(3)O_(4)to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network structure.As a consequence,the settling of copper matte droplets is enhanced due to the lowered slag viscosity,contributing to the high efficiency of copper-slag separation for copper recovery.The results provide new insights into the enhanced in-situ enrichment of copper from mol-ten slag. 展开更多
关键词 pyrometallurgical smelting process slag cleaning reductants copper matte
下载PDF
ZNT1 Involves Cuproptosis through Regulating MTF1-conduced Expression of MT1X under Copper Overload
14
作者 Wu Yue Yang Tingyun +4 位作者 Yan Bo Ai Youwei Chen Fang Ma Juan Liu Sijin 《生态毒理学报》 CAS CSCD 北大核心 2024年第4期53-70,共18页
Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o ... Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination. 展开更多
关键词 copper cuproptosis ZNT1 MT1X
下载PDF
Serum Zinc and Copper Level in Juvenile Idiopathic Arthritis (JIA) Patients and Its Correlation with Disease Duration-A Tertiary Hospital Study
15
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
下载PDF
Role of copper in central nervous system physiology and pathology
16
作者 Martina Locatelli Cinthia Farina 《Neural Regeneration Research》 SCIE CAS 2025年第4期1058-1068,共11页
Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central ne... Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central nervous system.Central copper dysregulations have been evidenced in two genetic disorders characterized by mutations in the copper-ATPases ATP7A and ATP7B,Menkes disease and Wilson’s disease,respectively,and also in multifactorial neurological disorders such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and multiple sclerosis.This review summarizes current knowledge about the role of copper in central nervous system physiology and pathology,reports about unbalances in copper levels and/or distribution under disease,describes relevant animal models for human disorders where copper metabolism genes are dysregulated,and discusses relevant therapeutic approaches modulating copper availability.Overall,alterations in copper metabolism may contribute to the etiology of central nervous system disorders and represent relevant therapeutic targets to restore tissue homeostasis. 展开更多
关键词 ASTROCYTES central nervous system copper CUPRIZONE multiple sclerosis MYELIN neurodegenerative disorders
下载PDF
Removal of rubidium from brine by an integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide
17
作者 Huanxi Xu Peihua Lin +6 位作者 Pei-Jun Liu Hai-Gang Liu Hui-Bin Guo Chao-Xiang Wu Ming Fang Xu Zhang Guan-Ping Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期112-121,共10页
A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonate... A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonated polysulfone/graphene(SPSG)was synthesized by phase conversion process,which was alternately immersed in 0.1 mol·L^(-1)CuSO_(4)/K_(4)[Fe(CN)_(6)]by in-situ adsorption coupled co-precipitation method.Various data such as nuclear magnetic resonance spectrometer,Fourier transform infrared spectroscope,X-ray photoelectron spectroscope,X-ray diffraction,scanning electron microscope,and energy dispersive spectroscopy all verified that abundant KCuFC were uniformly located on the film.The resulting KCuFC/SPSG was used in film separation system.As the solution was fed into the system,the Rb^(+)could be selectively adsorption by KCuFC/SPSG.After the saturation adsorption,0.5 mol·L^(-1)NH_(4)Cl/HCl was fed into the film cell,Rb^(+)could be quickly desorbed by ion-exchange between Rb^(+)and NH_(4)^(+)in the lattice of KCuFC.The purpose of separating and recovering Rb^(+)from the brine can be achieved after the repeated operation.The effects of pH,adsorption time,and interferential ions on the adsorption capacity of Rb^(+)were investigated by batch experiments.The adsorption behavior fits the pseudo-second order kinetic process,while KCuFC has a higher adsorption capacity(Langmuir maximum sorption 165.4 mg·g^(-1)).In addition,KCuFC/SPSG shows excellent selectivity for Rb^(+)even in complex brine systems.KCuFC/SPSG could maintain 93.5%extraction efficiency after five adsorption/desorption cycles. 展开更多
关键词 Rubidium extraction Potassium copper ferricyanide Sulfonated polysulfone Graphene oxide Adsorption
下载PDF
Efficient C-N coupling in electrocatalytic urea generation on copper carbonate hydroxide electrocatalysts
18
作者 Yinuo Wang Yian Wang +11 位作者 Qinglan Zhao Hongming Xu Shangqian Zhu Fei Yang Ernest P.Delmo Xiaoyi Qiu Chi Song Juhee Jang Tiehuai Li Ping Gao MDanny Gu Minhua Shao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期289-298,I0008,共11页
Urea generation through electrochemical CO_(2) and NO_(3)~-co-reduction reaction(CO_(2)NO_(3)RR)is still limited by either the low selectivity or yield rate of urea.Herein,we report copper carbonate hydroxide(Cu_2(OH)... Urea generation through electrochemical CO_(2) and NO_(3)~-co-reduction reaction(CO_(2)NO_(3)RR)is still limited by either the low selectivity or yield rate of urea.Herein,we report copper carbonate hydroxide(Cu_2(OH)_2CO_(3))as an efficient CO_(2)NO_(3)RR electrocatalyst with an impressive urea Faradaic efficiency of45.2%±2.1%and a high yield rate of 1564.5±145.2μg h~(-1)mg_(cat)~(-1).More importantly,H_(2) evolution is fully inhibited on this electrocatalyst over a wide potential range between-0.3 and-0.8 V versus reversible hydrogen electrode.Our thermodynamic simulation reveals that the first C-N coupling follows a unique pathway on Cu_2(OH)_2CO_(3) by combining the two intermediates,~*COOH and~*NHO.This work demonstrates that high selectivity and yield rate of urea can be simultaneously achieved on simple Cu-based electrocatalysts in CO_(2)NO_(3)RR,and provide guidance for rational design of more advanced catalysts. 展开更多
关键词 copper carbonate hydroxide Co-reduction Urea generation C-N coupling DFT calculation
下载PDF
The occurrence of metallic copper and redistribution of copper in the shocked Suizhou L6 chondrite
19
作者 Xiande Xie Xiangping Gu Yiping Yang 《Acta Geochimica》 EI CAS CSCD 2024年第5期827-837,共11页
Copper possesses very strong chacophile properties,but under the conditions found in meteorites,its behavior is like that of siderophile elements.The Suizhou meteorite is a highly shocked L6 chondrite.Troilite and tae... Copper possesses very strong chacophile properties,but under the conditions found in meteorites,its behavior is like that of siderophile elements.The Suizhou meteorite is a highly shocked L6 chondrite.Troilite and taenite are considered the main primary carrier of copper in this meteorite,and the post-shock thermal episode is considered the main reason that elemental Cu migrates from its original host phase and forms metallic grains.The Suizhou meteorite contains a few very thin shock melt veins.The occurrence and behavior of metallic copper in this meteorite were studied by optical microscopic examination,electron microprobe analyses,and high-resolution X-ray elemental intensity mapping.Our results show that metallic copper is abundant in the Suizhou chondritic rock.Metallic copper grains adjacent to small troilite grains inside FeNi metal are the most common occurrence,and those at the FeNi metal–troilite interface are the second most common case.The metallic copper grains occurring at the interface of FeNi metal/troililte and silicate are rather rare.Metallic copper grains are not observed within the Suizhou shock veins,Instead,Cu in elemental form is transferred through shock metamorphism into FeNi metal+troilite intergrowths.Four diff erent occurrence types of Cu in the FeNi metal+troilite intergrowths have been identifi ed:the concentrations of Cu in the FeNi+FeS intergrowths for four occurrence types are rather close,we estimate it might be lower than 1 wt%. 展开更多
关键词 Suizhou chondrite Shock vein Metallic copper Metal-troilite intergrowth Elemental intensity mapping
下载PDF
Effect of wire diameter compression ratio on drawing deformation of micro copper wire
20
作者 Tao HUANG Han-jiang WU +3 位作者 Ke-xing SONG Yan-min ZHANG Yan-jun ZHOU Shao-lin LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2605-2618,共14页
A crystal plasticity finite element model was developed for the drawing deformation of pure copper micro wire,based on rate-dependent crystal plasticity theory.The impact of wire diameter compression ratio on the micr... A crystal plasticity finite element model was developed for the drawing deformation of pure copper micro wire,based on rate-dependent crystal plasticity theory.The impact of wire diameter compression ratio on the micro-mechanical deformation behavior during the wire drawing process was investigated.Results indicate that the internal deformation and slip of the drawn wire are unevenly distributed,forming distinct slip and non-slip zones.Additionally,horizontal strain concentration bands develop within the drawn wire.As the wire diameter compression ratio increases,the strength of the slip systems and the extent of slip zones inside the deformation zone also increase.However,the fluctuating stress state,induced by contact pressure and frictional stress,results in a rough and uneven wire surface and diminishes the stability of the drawing process. 展开更多
关键词 micro copper wire drawing deformation crystal plasticity finite element slip mode
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部