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Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

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Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-feng xie Xing-Cheng xie Zhong-Wu Li Rui-Jun Cao Zhong-Kun Lin Qing Li Chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous MetalsBeijing100088China

The effects of cryogenic treatment(CT)and tempering-cryogenic treatment(TCT)on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were *** binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were *** results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles W_(x)Co_(y)C_(z) in the binder during the heat treatments of CT and *** the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarsegrained cemented carbide Carbon content Nanoparticlereinforced binder

Microstructures and mechanical properties of a commercial Mg-Al-Zn-Mn alloy with various hot-extrusion processes

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Rare Metals 2024年第3期43卷 1329-1336页

作者： He Ma Fan-Zhi Meng Qiang Yang Ze-feng xie Yuan-Ding Huang Xin Qiu State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun130022China MagIC-Magnesium Innovation Center Helmholtz-Zentrum Geesthacht21502GeesthachtGermany Engineering Research Center of Optoelectronic Functional Materials Ministry of EducationChangchun University of Science and TechnologyChangchun130022China

Mg-Al-Zn-Mn(AZ)system alloys have become widely used due to their good castability,excellent formability and outstanding corrosion resistance[1-6].However,their strength is still much lower than that of traditional Mg... 详细信息

关键词： alloys alloy corrosion

Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling

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Petroleum Science 2024年第2期21卷 741-751页

作者： Shuang-Biao Han Chao-Han Xiang Xin Du Lin-feng xie Jie Huang Cheng-Shan Wang College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China

The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen *** gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been *** on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different *** gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary *** increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to *** origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and *** shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic ***,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived *** discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.

关键词： Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin

A 12-month follow-up study of discharged patients with acute pancreatitis:An acute condition with prolonged sequela

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Chinese Medical Journal 2024年第2期137卷 250-252页

作者： Hanyue Ding Jiayuan Dai Jiaye Lin Liang Gong Han Sun Kai Song feng xie Dong Wu Department of Gastroenterology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China School of Population Medicine and Public Health Peking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China JC School of Public Health and Primary Care Faculty of MedicineThe Chinese University of Hong KongHong Kong Special Administrative RegionChina Emergency Department Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Department of Health Research Methods Evidence and ImpactMcMaster UniversityHamiltonCanada Centre for Health Economics and Policy Analysis McMaster UniversityHamiltonCanada State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Clinical Epidemiology Unit International Clinical Epidemiology NetworkBeijing 100730China

To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,000,probably due to a rising trend of obesity and gallstone *** is associated with remarkable pain,reduced quality of life(QoL),and even death,thus posing a heavy socioeconomic *** addition,approximately 22%of AP patients experience recurrent AP(RAP)and 10%of AP patients progress to chronic pancreatitis.[2]Petrov and Yadav[3]have,therefore,argued that AP should not be considered as an acute and self-limiting *** and long-term care after AP have drawn widespread attention,which has improved patients’physical and mental health.

关键词： patients pancreatitis acute

Properties and microstructure of copper–titanium alloys with magnesium additions

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Rare Metals 2024年第5期43卷 2290-2299页

作者： Lue Huang Li-Jun Peng Jiang Li Xu-Jun Mi Gang Zhao Guo-Jie Huang Hao-feng xie Yi-Cheng Cao Wen-Jing Zhang Zhen Yang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd.Beijing 100088China GRIMAT Engineering Institute Co. LtdBejing 101407China School of Materials Science and Engineering Northeastern UniversityShenyang110000China General Research Institute for Nonferrous Metals Beijing 100088China China Academy of Space Technology Beijing 100094China China Nonferrous Metals Mining Group(Tianjin)Co.Ltd Tianjin 3001llChina

The volume fractions and morphology of precipitates in precipitation-strengthened Cu-Ti alloys,which precipitate mainly as continuous and discontinuous precipitates,are important for the application of the *** study employed hardness and electrical conductivity tests transmission electron microscopy(TEM),atom probe tomography(APT),and first-principles calculations to demonstrate that the addition of Mg is effective for accelerating nanosized continuousβ'-Cu_(4)Ti precipitation as well as for suppressing the precipitation of coarse lamellar discontinuousβ-Cu_(4)Ti precipitates along the grain boundaries,resulting in Cu-Ti alloys with high yield strength and good electrical *** results showed that the continuous precipitation ofβ'-Cu_(4)Ti was accelerated by the Mg additions,which reduced the supersaturation of the matrix,thereby reducing the chemical driving force for the discontinuous *** the other hand,Mg additions increased the mismatch between the discontinuousβ-Cu_(4)Ti precipitates and matrix decreased the nucleation rate of the discontinuous precipitates,and increased the spacing of the discontinuous precipitation layer,resulting in a lower growth rate of the discontinuous ***,the addition of Mg to Cu-Ti alloys enhances the strength and improves the resistance to over-ageing.

关键词： Cu-Ti-Mg alloy Precipitation hardening Discontinuous precipitation Continuous precipitation Microstructure formation mechanism

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氧化铜精矿熔炼过程中铜、钴、铁的还原行为

东北大学学报（自然科学版） 2024年第3期45卷 337-345页

作者：张磊蒋开喜谢锋路殿坤东北大学冶金学院辽宁沈阳110819 矿冶科技集团有限公司北京100044 福州大学紫金地质与矿业学院福建福州350108

针对刚果金含钴氧化铜精矿采用铁橄榄石渣型进行了焦炭还原熔炼,考察了m(CaO)/m(SiO_(2)),m(FeO)/m(SiO_(2))和焦比等对铜、钴还原率的影响.对铜、钴、铁和硅氧化物的还原顺序和还原条件进行了热力学分析,借助金属氧化物还原热力学模型... 详细信息

针对刚果金含钴氧化铜精矿采用铁橄榄石渣型进行了焦炭还原熔炼,考察了m(CaO)/m(SiO_(2)),m(FeO)/m(SiO_(2))和焦比等对铜、钴还原率的影响.对铜、钴、铁和硅氧化物的还原顺序和还原条件进行了热力学分析,借助金属氧化物还原热力学模型与焦炭气化动力学对铜、钴、铁氧化物的还原进程进行了量化分析.研究结果表明,氧化铜精矿中金属铜、钴、铁的还原分为前期的竞争性快速还原期和后期的铜、钴慢速还原期,在慢速还原期已经还原的金属铁还会发生再氧化;金属铁前期大量的竞争性还原和后期的再氧化会降低铜、钴、铁的还原率和焦炭的有效利用率.揭示了粗铜表面铁合金层的形成机制.

关键词：氧化铜精矿铜钴 FeO还原热力学模型铁橄榄石

维普期刊数据库博看期刊

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黑木耳粉对黑米凝胶物化特性及结构的影响

粮油食品科技 2024年第2期32卷 83-91页

作者：董越谢枫肖建辉江西省农业科学院园艺研究所江西南昌330200 江西农业大学食品科学与工程学院江西南昌330045

为了改善黑米的加工性能,以黑米粉为原料,通过添加不同量的黑木耳粉(5.0%、10.0%、15.0%、20%),考察其对黑米粉糊化特性、热力学特性及其形成黑米凝胶的流变特性、质构特性以及微观结构的影响。添加黑木耳粉可以显著提高黑米的粘度并促... 详细信息

为了改善黑米的加工性能,以黑米粉为原料,通过添加不同量的黑木耳粉(5.0%、10.0%、15.0%、20%),考察其对黑米粉糊化特性、热力学特性及其形成黑米凝胶的流变特性、质构特性以及微观结构的影响。添加黑木耳粉可以显著提高黑米的粘度并促进冷却过程中的凝胶化,其中添加量为20%的黑木耳粉效果最好。添加黑木耳粉会抑制黑米凝胶内水分的流动,使硬度及弹性显著增大,糊化焓从3.01 J/g增加到5.94 J/g,羟基伸缩振动峰从3390 cm^(–1)降低到3374 cm^(–1),黑木耳粉可以提高黑米凝胶结构的稳定性。扫描电镜结果显示,添加黑木耳粉的黑米凝胶孔洞明显小于纯黑米凝胶,且孔洞周围的基质层较厚,进一步解释了黑木耳粉对改善黑米凝胶结构效果的机制。综上可见,添加黑木耳粉对黑米凝胶物化特性和结构影响显著。

关键词：黑米黑木耳粉物化特性凝胶结构

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基于CDs/AuNCs@ZIF-8的双发射比率荧光传感器快速检测铅离子

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分析试验室 2024年第8期43卷 1190-1195页

作者：刘素青谢锋周艳何雨教育部环境污染监测与疾病控制重点实验室贵州医科大学公共卫生与健康学院贵阳561113 贵州省分析测试研究院贵阳550002

将碳点(CDs)和发光材料金纳米团簇(AuNCs)封装在沸石咪唑酸框架(ZIF-8)中,构建了CDs/AuNCs@ZIF-8双发射比率荧光传感器。表征了其形貌和光学性能,探讨了铅离子(Pb^(2+))对该比率探针的荧光猝灭机理。根据Pb^(2+)对比率探针的猝灭作用,... 详细信息

将碳点(CDs)和发光材料金纳米团簇(AuNCs)封装在沸石咪唑酸框架(ZIF-8)中,构建了CDs/AuNCs@ZIF-8双发射比率荧光传感器。表征了其形貌和光学性能,探讨了铅离子(Pb^(2+))对该比率探针的荧光猝灭机理。根据Pb^(2+)对比率探针的猝灭作用,利用该比率探针的荧光强度比值(F_(644)/F_(460))的变化定性定量检测Pb^(2+)。在最佳条件下,CDs/AuNCs@ZIF-8对Pb^(2+)的检测范围为9~140μmol/L,检出限为3.61μmol/L。将该双发射比率荧光传感器应用于实际水样的测定,加标回收率在93.0%~111.2%之间,相对标准偏差(RSD)小于7.0%。该方法能够用于实际样品中Pb^(2+)的检测。

关键词：双发射比率荧光传感器金纳米团簇碳量子点铅离子

金刚石/铜-硼复合材料界面结构及其对热导率和力学性能的影响

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Transactions of Nonferrous Metals Society of China 2024年第1期34卷 246-254页

作者：谢忠南郭宏肖伟张习敏黄树晖孙明美解浩峰有研科技集团有限公司有色金属结构材料制备加工国家重点实验室北京100088 有研工程技术研究院有限公司北京101407 北京有色金属研究总院北京100088

通过控制硼含量制备不同界面结构的金刚石/铜复合材料,研究复合材料的界面显微组织及其对热性能和力学性能的影响。结果表明,界面处形成微米级B4C齿状结构,该结构为界面结合提供冶金结合和机械啮合的双重作用。金刚石/铜-硼复合材料获... 详细信息

通过控制硼含量制备不同界面结构的金刚石/铜复合材料,研究复合材料的界面显微组织及其对热性能和力学性能的影响。结果表明,界面处形成微米级B4C齿状结构,该结构为界面结合提供冶金结合和机械啮合的双重作用。金刚石/铜-硼复合材料获得最高为695 W/(m·K)的热导率和535 MPa的弯曲强度。金刚石与B4C之间形成具有金刚石(111)//B4C (104)取向关系的半共格界面。微纳米级齿状结构可提高界面声子传输效率和界面结合强度。

关键词：金属基复合材料金刚石/铜复合材料热导率界面结构