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EFFECTS OF Pb COMPOUND ADDITIVES ON THE PROPERTIES OF YBa_2Cu_3O_(7-δ) 被引量:3
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作者 F.H.Li Z.G.Fan +3 位作者 J.Wang C.S.Liu D.W.Soh Y.J.Cho 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第2期145-148,共4页
The melting temperature and critical transition temperature Tc of YBa2Cu3O7-δ with deferent content additives of PbO and BaPbO3 were studied. When PbO was doped in YBa2Cu3O7-δ, the melting temperature of YBa2Cu3O7-... The melting temperature and critical transition temperature Tc of YBa2Cu3O7-δ with deferent content additives of PbO and BaPbO3 were studied. When PbO was doped in YBa2Cu3O7-δ, the melting temperature of YBa2Cu3O7-δ was reduced, however its superconductivity was weakened. From the XRD pattern of the sintered mixture of YBa2Cu3O7-δ and PbO, it was known that there was a reaction between YBa2Cu3O7-δ and PbO, and the product was BaPbO3. Hence different contents of BaPbO3 (10mass%, 20mass% and 30mass%) were added in YBa2Cu3O7-δ. It was proved that there were no reactions between YBa2Cu3O7-δ and BaPbO3. And the superconductivity of the mixtures was much better than that of the samples with PbO additive. 展开更多
关键词 YBA2CU3O7-Δ PbO additive melting temperature SUPERCONDUCTIVITY
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Alkali Metal-incorporated Mesoporous Smectites:Crystallinity and Textural Properties 被引量:1
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作者 HE Yan feng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期253-256,共4页
A series of mesoporous smectite like materials incorporated with alkali metals such as Li, Na, K and Cs has been synthesized with the hydrothermal method. The crystalline and the pore structures of the materials synt... A series of mesoporous smectite like materials incorporated with alkali metals such as Li, Na, K and Cs has been synthesized with the hydrothermal method. The crystalline and the pore structures of the materials synthesized significantly change with the introduction of alkali metals. The addition of Li gives highly ordered layer phases, while the incorporation of Cs yields much less crystalline structures. Although Na or K has little effect on the crystalline structure, they modify the pore structure. 展开更多
关键词 Mesoporous material alkali metal additive effect Crystalline structure Pore structure
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双添加剂低浓度水系硫酸盐电解液用于2V碳-碳超级电容器
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作者 郭宇 张然 +2 位作者 李刚 王开鹰 潘跃德 《微纳电子技术》 CAS 北大核心 2023年第8期1174-1184,共11页
为了解决水系电解液在超级电容器中电压窗口低、能量密度小的问题,研究了含有0.5 mol/L硫酸钾(K_(2)SO_(4))以及聚乙二醇(PEG)和碱金属碘化物(AMI)双添加剂的低浓度中性水系电解液在碳-碳超级电容器中的应用。首先在0.5 mol/L K_(2)SO_... 为了解决水系电解液在超级电容器中电压窗口低、能量密度小的问题,研究了含有0.5 mol/L硫酸钾(K_(2)SO_(4))以及聚乙二醇(PEG)和碱金属碘化物(AMI)双添加剂的低浓度中性水系电解液在碳-碳超级电容器中的应用。首先在0.5 mol/L K_(2)SO_(4)中添加PEG,由于H2O-PEG之间的相互作用,3%质量分数的PEG添加剂使得0.5 mol/L K_(2)SO_(4)电解液的电化学稳定窗口达到4.70 V。该0.5 mol/L K_(2)SO_(4)+3%PEG电解液应用于以商业活性炭YP-50F作为电极材料的碳-碳超级电容器中,可在2V条件下稳定循环10000次。进一步添加AMI(LiI、NaI或KI)氧化还原添加剂来增大比电容和能量密度,使法拉第反应的比电容进一步提高到400 F·g^(-1)以上,是原始0.5 mol/L K_(2)SO_(4)+3%PEG电解液的3.5倍,能量密度达到50 W·h·kg^(-1)以上。此外,根据电双层电容器的离子孔尺寸匹配理论,LiI和NaI被证明是比KI更有效的添加剂,它们能使得YP-50F丰富的亚纳米孔得到更有效的利用。因此,PEG和AMI的协同作用为超级电容器水系电解液的开发提供了一种可行的方案。 展开更多
关键词 超级电容器 中性水系电解液 碱金属碘化物(AMI) 氧化还原添加剂 协同作用
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The Reductive Addition Reaction of Substituted 2-Chloromethyl-1,3,4-oxadiazole to Aldehydes and Ketones Promoted by Samarium Diiodide
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作者 Xiao Liang XU Wei Min ZHU Yong Min ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第12期1566-1568,共3页
1-(β-Hydroxyalkyl)-l,3,4-oxadiazole derivatives were synthesized via reductive addition reactions of 2-chloromethyl-l,3,4-oxadiazole with carbonyl compounds under mild conditions promoted by SmI2.
关键词 Reductive addition samarium diiodide 1-(β-hydroxyalkyl)-1 3 4-oxadiazole deriva-tives SYNTHESIZE
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Grain selection and growth orientation of prior-β phase for Ti-6-4 during additive manufacturing:insights from a modeling perspective
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作者 Wei-zhao Sun Fei-hu Shan +2 位作者 Nan-fu Zong Hong-biao Dong Tao Jing 《China Foundry》 SCIE CAS 2021年第2期83-93,共11页
The microstructure of Ti-6-4 components produced by additive manufacturing suffers from the coarse and elongated prior-β grain,which leads to a decrease of the tensile behavior and the occurrence of anisotropy.To und... The microstructure of Ti-6-4 components produced by additive manufacturing suffers from the coarse and elongated prior-β grain,which leads to a decrease of the tensile behavior and the occurrence of anisotropy.To understand and control the grain evolution,a multiscale simulation is applied to investigate the relationship between the grain selection,growth orientation,and the molten pool morphology with the different deposition layer numbers and processing parameters.The accuracy of the simulation is validated by experiments in both qualitative and quantitative ways.Results show that when the grain with unfavorable orientation loses the competitive growth with its neighbors,there will be a great chance that the blocked grain is eliminated in the following layer-and-layer deposition,which leads to the increase of the grain width.The size of the molten pool increases remarkably as the layer number increases,which lays a heavy burden on the stability of the molten pool.The analytical relationship between the molten pool morphology and the grain growth orientation is also deduced.The flat molten pool causes the grains with the <001> direction close to the building direction to have greater survival potential.Besides,decreasing the line power energy shows little effect on the stability of the molten pool and the grain growth orientation,especially when the deposited layer number is large.The revealing mechanisms will help in understanding and further controlling the grain evolution. 展开更多
关键词 additive manufacturing Ti-6-4 simulation grain selection grain growth
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Effect of Pelletized Graphite Addition on Properties of Al_2O_3-SiC-C Castables
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作者 ZHAO Chenrui ZHANG Sanhua +2 位作者 WANG Guan WEI Yi YUAN Cong 《China's Refractories》 CAS 2015年第4期42-46,共5页
Al2O3 - SiC - C castables with pelletized graphite addition of 0. 2%, 4% or 6% (by mass, the same hereinafter ) were prepared using brown fused corundum (8 - 5, 5 - 3 and 3 - 1 mm ) , dense fused corundum ( ≤1 a... Al2O3 - SiC - C castables with pelletized graphite addition of 0. 2%, 4% or 6% (by mass, the same hereinafter ) were prepared using brown fused corundum (8 - 5, 5 - 3 and 3 - 1 mm ) , dense fused corundum ( ≤1 and 0. 045 mm) and SiC ( ≤1 and ≤0. 064 mm) its main starting materials with mass ratio of aggregate: matrix = 71: 29, 2% silicon powder and 0. 4% B4C as antioxidants, and pelletized graphite as carbon source, Effect of pelletized graphite addition on physical properties, oxidation resistance, slag resistance arid thermal shock resistance of Al2O3 -SiC- C eastables was researched. The results show that: with the in.crease of pelletized graphite addition, the required water amount of castables increases, the bulk density and strength reduce; with 4% pelletized graphite, the eastable performs the best oxidation resistance; the increase of graphite is beneficial to the improvement of slag penetration resistance and corrosion resistance; with 6% pelletized graphite, the thermal shock resistance is the best. 展开更多
关键词 pelletized graphite additION alumina - silicon carbide- carbon castable corrosion resistance
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Effect of TiO2 Addition on Slag Resistance of Lightweight Corundum-spinel Castables
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作者 MA Sanbao YAN Wen +1 位作者 LIN Xiaoli ZHOU Wenying 《China's Refractories》 CAS 2017年第4期44-49,共6页
Five lightweight castables containing different TiO2 additions were prepared by using porous corundum - spinel ( MgAl2O4 ) ceramics as aggregate. Corrosion of the lightweight cstables by ladle slag was conducted u... Five lightweight castables containing different TiO2 additions were prepared by using porous corundum - spinel ( MgAl2O4 ) ceramics as aggregate. Corrosion of the lightweight cstables by ladle slag was conducted using a static crucible test. The effect of the TiO2 addition on the slag resistances of the lightweight corundum -spinel castables was investigated through SEM, EDS and Fact- Sage@ software, etc. h was found that TiO2 additi,ve t,vmoted the sintering degree of the castables, deereased the average pore .size, the apparent porosity, and the contact area between the casmbles and slag, and then en- hanced the corrosion resistance. However, TiO2 additive decreased the viscosity of the penetrated .slag simultane- ously, and then deteriorated the penetration resistance. 展开更多
关键词 lightweight eastables porous corundum - spinel aggregate titania addition microstructure slag ladle
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Designing Advanced Liquid Electrolytes for Alkali Metal Batteries:Principles,Progress,and Perspectives
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作者 Wanming Teng Junxiong Wu +10 位作者 Qinghua Liang Jiaojiao Deng Yu Xu Qiong Liu Biao Wang Ting Ma Ding Nan Jun Liu Baohua Li Qingsong Weng Xiaoliang Yu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期353-380,共28页
The ever-growing pursuit of high energy density batteries has triggered extensive efforts toward developing alkali metal(Li,Na,and K)battery(AMB)technologies owing to high theoretical capacities and low redox potentia... The ever-growing pursuit of high energy density batteries has triggered extensive efforts toward developing alkali metal(Li,Na,and K)battery(AMB)technologies owing to high theoretical capacities and low redox potentials of metallic anodes.Typically,for new battery systems,the electrolyte design is critical for realizing the battery electrochemistry of AMBs.Conventional electrolytes in alkali ion batteries are generally unsuitable for sustaining the stability owing to the hyper-reactivity and dendritic growth of alkali metals.In this review,we begin with the fundamentals of AMB electrolytes.Recent advancements in concentrated and fluorinated electrolytes,as well as functional electrolyte additives for boosting the stability of Li metal batteries,are summarized and discussed with a special focus on structure-composition-performance relationships.We then delve into the electrolyte formulations for Na-and K metal batteries,including those in which Na/K do not adhere to the Li-inherited paradigms.Finally,the challenges and the future research needs in advanced electrolytes for AMB are highlighted.This comprehensive review sheds light on the principles for the rational design of promising electrolytes and offers new inspirations for developing stable AMBs with high performance. 展开更多
关键词 advanced liquid electrolytes alkali metal batteries concentrated and fluorinated electrolytes functional electrolyte additives
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外加剂对碱激发胶凝材料干燥收缩性能的影响
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作者 范小春 杨东升 +2 位作者 张宇 高旭 喻立举 《硅酸盐通报》 CAS 北大核心 2024年第8期2788-2796,共9页
为了进一步改善碱激发胶凝材料的收缩特性,探索了单掺有机减缩剂(聚乙二醇和乳胶)、无机膨胀剂(CaO、MgO和石膏)对矿渣粉煤灰复合碱激发(AASF)体系水化产物组成、孔隙结构和收缩特性的影响。结果表明,在所有的外加剂中,聚乙二醇减缩效... 为了进一步改善碱激发胶凝材料的收缩特性,探索了单掺有机减缩剂(聚乙二醇和乳胶)、无机膨胀剂(CaO、MgO和石膏)对矿渣粉煤灰复合碱激发(AASF)体系水化产物组成、孔隙结构和收缩特性的影响。结果表明,在所有的外加剂中,聚乙二醇减缩效果最显著,外掺1%(质量分数)聚乙二醇的AASF试样的91 d干燥收缩仅为1 683με,相较于对照组最大降低29.7%,这主要归因于孔隙结构的显著粗化。聚乙二醇和乳胶对AASF的抗压强度有一定的负面影响,主要源于水化反应程度的降低和整体孔隙率的增加。三种无机膨胀剂在AASF体系中发挥出的收缩补偿效果不强,但对抗折强度有显著的增益效果。 展开更多
关键词 外加剂 胶凝材料 碱激发 干燥收缩 物相组成 孔隙结构
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纳米硒饲料添加剂在盐碱胁迫抗性提升中的应用前景
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作者 车兴华 耿龙武 +4 位作者 尚信池 张晴 魏海军 李望 徐伟 《饲料工业》 CAS 北大核心 2024年第20期144-152,共9页
我国“三北”内陆地区拥有大量的盐碱湖泊、地下咸水和盐碱沼泽等水资源,由于水体具有高盐度、高碳酸盐碱度、高硬度和离子组成复杂等特点,在渔业生产开发利用中存在苗种成活率低、生长缓慢、饲料成本高、经济效益差等问题,严重限制了... 我国“三北”内陆地区拥有大量的盐碱湖泊、地下咸水和盐碱沼泽等水资源,由于水体具有高盐度、高碳酸盐碱度、高硬度和离子组成复杂等特点,在渔业生产开发利用中存在苗种成活率低、生长缓慢、饲料成本高、经济效益差等问题,严重限制了盐碱水渔业的快速发展。硒(Se)是水生动物必需的微量元素之一,在提高机体免疫和抗逆性等方面的功效显著,有利于缓解盐碱胁迫等非生物胁迫对机体产生的氧化损伤。文章分析了我国盐碱水域渔业开发所面临的难题,纳米硒在清除自由基、提高抗氧化和免疫水平的优势。在盐碱水渔业生产中,纳米硒将有可能作为功能性饲料添加剂,提高鱼类的生产性能和耐盐碱性。 展开更多
关键词 盐碱水 渔业 纳米硒 饲料添加剂 应用前景
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碳热还原条件下SiO_2-Al_2O_3系耐火材料的腐蚀行为 被引量:5
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作者 李伟 孙康 +1 位作者 吴剑辉 刘明月 《有色金属》 CSCD 2001年第4期44-46,共3页
以粘土质和高铝质耐火砖为对象 ,采用计算机控制的热重分析系统 ,研究耐火材料在碳热还原反应条件下的腐蚀行为 ,碱金属添加剂对耐火材料腐蚀过程的影响 ,寻求耐火材料的防腐蚀措施。实验结果表明 ,碳热还原过程中 ,SiO2 -Al2 O3 系耐... 以粘土质和高铝质耐火砖为对象 ,采用计算机控制的热重分析系统 ,研究耐火材料在碳热还原反应条件下的腐蚀行为 ,碱金属添加剂对耐火材料腐蚀过程的影响 ,寻求耐火材料的防腐蚀措施。实验结果表明 ,碳热还原过程中 ,SiO2 -Al2 O3 系耐火材料会受到轻度腐蚀 ,相同条件下 ,HB2 0 -0 9#粘土砖侵蚀最严重 ,高铝砖的耐蚀效果最好 ;碱金属添加剂加重耐火材料受侵蚀的程度 ,添加剂用量愈大影响愈大 ;稀土氧化物有抑制和减缓耐火材料腐蚀的作用 ,尤以CeO2 的效果显著。 展开更多
关键词 耐火材料 碳热还原反应 碱金属添加剂 稀土氧化物 腐蚀 火法冶金
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生物质灰对煤焦气化反应的影响
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作者 丁亮 张旭 +4 位作者 魏佳乐 李文远 李伟鹏 王志青 房倚天 《洁净煤技术》 CAS CSCD 北大核心 2024年第2期72-83,共12页
生物质灰富含碱金属及碱土金属(AAEM),可作为天然催化剂应用于煤催化气化。生物质灰对煤焦气化反应促进作用也是生物质与煤共气化协同作用的本质原因。然而,生物质灰中AAEM在煤气化过程中会失活,失去部分催化作用。通过固定床热解及气... 生物质灰富含碱金属及碱土金属(AAEM),可作为天然催化剂应用于煤催化气化。生物质灰对煤焦气化反应促进作用也是生物质与煤共气化协同作用的本质原因。然而,生物质灰中AAEM在煤气化过程中会失活,失去部分催化作用。通过固定床热解及气化试验,结合XRD、Raman、XRF及BET等手段,分析了生物质灰种类、添加量、气化温度等因素对煤焦气化反应的影响。结果表明,生物质灰对煤焦气化反应催化作用与AAEM含量及存在形态相关。煤焦气化反应速率随小麦秸秆灰添加量增大而增大,小麦秸秆灰添加量达40%时,煤焦气化反应速率变化趋于平缓。气化反应前期,小麦秸秆灰对煤焦气化反应存在抑制作用;随转化率升高,在相同转化率下,温度越高,小麦秸秆灰催化作用越弱。为抑制小麦秸秆灰中K的失活,以蛋壳作为添加剂,探究了小麦秸秆灰与蛋壳的混灰对煤焦气化反应的影响。结果表明,25%小麦秸秆灰与5%蛋壳的混灰,可进一步增强小麦秸秆灰对煤焦气化反应催化作用。添加小麦秸秆灰使煤焦在气化过程中比表面积增大,孔隙结构丰富,石墨化程度减弱,无定形碳含量增加,气化反应活化能降低,气化反应速率增大。煤焦及添加小麦秸秆灰煤焦气化反应采用随机孔模型模拟效果最好。研究结果为生物质灰在煤催化气化中的应用提供参考。 展开更多
关键词 生物质灰 煤催化气化 碱金属失活 钙基添加剂 气化反应动力学
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电感耦合等离子体原子发射光谱法(ICP-OES)测定铍铀伴生矿石中的铍 被引量:5
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作者 杜桂荣 赵杰 +2 位作者 丁红芳 刘扬 王春叶 《中国无机分析化学》 CAS 2015年第2期30-33,共4页
建立了电感耦合等离子体原子发射光谱法(ICP-OES)测定铍铀伴生矿石中的铍的方法,研究了酸溶-碱熔融法溶样过程中加入的焦硫酸钾,对ICP-OES法测定铍铀伴生矿石中的铍含量产生的基体干扰问题。主要阐述消除基体干扰的一些措施。从实验... 建立了电感耦合等离子体原子发射光谱法(ICP-OES)测定铍铀伴生矿石中的铍的方法,研究了酸溶-碱熔融法溶样过程中加入的焦硫酸钾,对ICP-OES法测定铍铀伴生矿石中的铍含量产生的基体干扰问题。主要阐述消除基体干扰的一些措施。从实验数据可知,控制称样量、焦硫酸钾加入量、定容体积和加标稀释倍数,能够有效消除焦硫酸钾对ICP-OES法测定结果的基体干扰,6次平行测定结果的相对标准偏差为3.4%,加标回收率为98.7%~104.4%,实验表明,方法准确、可靠。 展开更多
关键词 电感耦合等离子体发射光谱法 标准加入法 酸溶-碱熔融 铍铀伴生矿
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外源添加物对不同土地利用方式下土壤肥力的影响
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作者 邓博 郭澎 +4 位作者 卫磊嘉 陈上茂 马泽 陈丹 毕利东 《中国农学通报》 2024年第8期91-100,共10页
本研究旨在探讨不同土地利用方式(林地、水田和旱田)下,外源添加物对土壤肥力的影响。通过在3种土地利用方式的土壤样品中分别添加生石灰(1 g/kg)、黄腐酸(10 g/kg)、鱼塘底泥(250 g/kg)和生物炭(15 g/kg)4种外源添加物,分析其对土壤碱... 本研究旨在探讨不同土地利用方式(林地、水田和旱田)下,外源添加物对土壤肥力的影响。通过在3种土地利用方式的土壤样品中分别添加生石灰(1 g/kg)、黄腐酸(10 g/kg)、鱼塘底泥(250 g/kg)和生物炭(15 g/kg)4种外源添加物,分析其对土壤碱解氮、速效磷和速效钾含量的影响。结果显示,在相同外源添加物条件下,土壤碱解氮含量呈旱田>林地>水田的趋势,速效磷含量呈耕作层水田>旱田>林地、犁底层旱田>水田>林地的趋势,速效钾含量无明显规律。具体而言,生石灰对碱解氮无显著影响,但使速效磷平均增加14.87%,速效钾平均减少6.19%。黄腐酸对碱解氮含量影响不大,却导致速效磷平均下降16.36%和速效钾平均下降12.94%。鱼塘底泥显著提高了林地、水田和旱田的土壤速效养分,其中碱解氮平均增加57.68%,速效磷平均增加170.16%,速效钾平均增加20.05%,这表明鱼塘底泥不仅直接提供速效养分,还能促进微生物生长,间接提升土壤肥力。生物炭对碱解氮含量影响不显著,但显著增加了各土样的速效磷和速效钾含量,平均增幅分别为89.80%和65.02%。综上所述,4种外源添加物对不同土地利用方式下的土壤肥力有显著差异,其中生物炭和鱼塘底泥的施用对提高土壤肥力尤为有效。 展开更多
关键词 外源添加物 土壤速效养分 土地利用方式 土壤肥力 碱解氮 速效磷 速效钾
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Analyzing the Interplay of Sintering Conditions on Microstructure and Hardness in Indirect Additive Manufacturing of 17-4PH Stainless Steel
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作者 Erika Lannunziata Mohammad Hossein Mosallanejad +2 位作者 Manuela Galati Gabriele Piscopo Abdollah Saboori 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第9期1611-1620,共10页
Indirect additive manufacturing(AM)methods have recently attracted attention from researchers thanks to their great potential for cheap,straightforward,and small-scale production of metallic components.Atomic diffusio... Indirect additive manufacturing(AM)methods have recently attracted attention from researchers thanks to their great potential for cheap,straightforward,and small-scale production of metallic components.Atomic diffusion additive manufacturing(ADAM),a variant of indirect AM methods,is a layer-wise indirect AM process recently developed based on fused deposition modeling and metal injection molding.However,there is still limited knowledge of the process conditions and material properties fabricated through this process,where sintering plays a crucial role in the final consolidation of parts.Therefore,this research,for the first time,systematically investigates the impact of various sintering conditions on the shrinkage,relative density,microstructure,and hardness of the 17-4PH ADAM samples.For this reason,as-washed samples were sintered under different time-temperature combinations.The sample density was evaluated using Archimedes,computed tomography,and image analysis methods.The outcomes revealed that sintering variables significantly impacted the density of brown 17-4PH Stainless Steel samples.The results indicated more than 99% relative densities,higher than the value reported by Markforged Inc.(~96%).Based on parallel porosities observed in the computed tomography results,it can be suggested that by modifying the infill pattern during printing,it would be possible to increase the final relative density.The microhardness of the sintered samples in this study was higher than that of the standard sample provided by Markforged Inc.Sintering at 1330℃ for 4 h increased the density of the printed sample without compromising its mechanical properties.According to X-ray diffraction analysis,the standard sample provided by Markforged Inc.and“1330℃—4 h”one had similar stable phases,although copper-rich intermetallics were more abundant in the microstructure of reference samples.This study is expected to facilitate the adoption of indirect metal AM methods by different sectors,thanks to the high achievable relative densities reported here. 展开更多
关键词 Indirect additive manufacturing Atomic diffusion additive manufacturing 17-4PH stainless steel Computed tomography SINTERING
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混掺PP纤维对碱矿渣混凝土性能的影响分析
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作者 张恒 《路基工程》 2024年第4期113-117,共5页
采用碱矿渣混凝土替代传统水泥混凝土并掺入PP纤维,探究单掺粗PP纤维与混掺粗、细PP纤维对碱矿渣混凝土流动性能、力学性能、劈裂抗拉性能及收缩性能的影响。结果表明:掺入PP纤维会对混凝土流动性产生负面影响,但力学性能与劈裂抗拉性... 采用碱矿渣混凝土替代传统水泥混凝土并掺入PP纤维,探究单掺粗PP纤维与混掺粗、细PP纤维对碱矿渣混凝土流动性能、力学性能、劈裂抗拉性能及收缩性能的影响。结果表明:掺入PP纤维会对混凝土流动性产生负面影响,但力学性能与劈裂抗拉性能均有不同程度提升;混掺条件下各性能改善效果最优,其中7天、28天劈裂抗拉最高分别提升19.41%和23.30%;收缩徐变情况明显改善,B2组7天、28天收缩徐变较对照组分别降低14.29%、20.58%;混掺PP纤维可有效提高碱矿渣混凝土力学性能,且缓解前期强度发展过程中的收缩开裂问题。 展开更多
关键词 碱矿渣混凝土 PP纤维 掺入量 收缩特性 流动性能 力学性能
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柱后加碱-高效阴离子交换色谱-脉冲安培检测法测定农田土中草铵膦、氨甲基膦酸和草甘膦残留 被引量:11
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作者 陶雪梅 朱红霞 +1 位作者 高立红 李仁勇 《色谱》 CAS CSCD 北大核心 2019年第9期1004-1010,共7页
应用柱后加碱-高效阴离子交换色谱-脉冲安培检测法同时测定了农田土中草铵膦、氨甲基膦酸和草甘膦的残留。土壤样品用2 mmol/L 氢氧化钠振荡提取,混匀后依次用0.22 μ m滤膜、IC-C 18 和IC-Na柱处理。滤液中的3种目标物和共存离子经IonP... 应用柱后加碱-高效阴离子交换色谱-脉冲安培检测法同时测定了农田土中草铵膦、氨甲基膦酸和草甘膦的残留。土壤样品用2 mmol/L 氢氧化钠振荡提取,混匀后依次用0.22 μ m滤膜、IC-C 18 和IC-Na柱处理。滤液中的3种目标物和共存离子经IonPacAS11-HC离子色谱柱分离,柱后加碱-脉冲安培检测器检测。结果表明,草铵膦和草甘膦质量浓度在20.0~ 1 000 μ g/L 、氨甲基膦酸质量浓度在5.0~ 400 μ g/L 范围内线性关系良好,相关系数均大于0.999。草铵膦、氨甲基膦酸和草甘膦的检出限分别为0.08、0.02和0.04 mg/kg ,回收率为80.2%~106%,相对标准偏差为0.7%~5.0%( n =6)。该方法抗干扰性强、灵敏度和准确度高,操作简便快捷,适用于农田土中草铵膦,氨甲基膦酸和草甘膦残留量的检测。 展开更多
关键词 柱后加碱 高效阴离子交换色谱 脉冲安培检测 草铵膦 氨甲基膦酸 草甘膦 农田土
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Catalytic Mechanism of KCl during Carbothermic Reduction of Pre-Oxidized Ilmenite 被引量:2
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作者 SUN Kang WU Jian-hui 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2001年第2期7-11,共5页
As alkali additive,KC1 catalyzes effectively the carbothermic reduction of pre-oxidized ilmenite,and the catalytic effect becomes more remarkable as the amount of KC1 increases.During the carbothermic reduction,the ga... As alkali additive,KC1 catalyzes effectively the carbothermic reduction of pre-oxidized ilmenite,and the catalytic effect becomes more remarkable as the amount of KC1 increases.During the carbothermic reduction,the gaseous product consists mainly of CO,and the partial pressure of which increases with reaction temperature.The EPMA and XPS of the partially reduced ilmenite ore and that of the used graphite as reductant showed that the potassium ions enter both ilmenite particles and graphite powders during reduction.The above-mentioned phenomena result in the distortion of ilmenite and carbon structure by potassium ions and reaction activity of carbon and ilmenite was enhanced.As a result,the overall carbothermic reduction was catalyzed by KC1. 展开更多
关键词 carbothermic reduction catalytic effect reaction mechanism alkali additives preoxidized ilmenite
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Catalytic effect of alkali chlorides on carbothermic reduction of pre oxidized ilmenite 被引量:1
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作者 吴剑辉 孙康 +2 位作者 马跃宇 刘明月 张永健 《中国有色金属学会会刊:英文版》 CSCD 2000年第6期813-816,共4页
A computer monitoring thermogravimetric system was used to study the effect of alkali chlorides(MCl, M=Li, Na, K and Cs) on the carbothermic reduction of pre oxidized ilmenite in the course of a linear rise in tempera... A computer monitoring thermogravimetric system was used to study the effect of alkali chlorides(MCl, M=Li, Na, K and Cs) on the carbothermic reduction of pre oxidized ilmenite in the course of a linear rise in temperature from 600 ℃ to 1 000 ℃. The experimental results indicate that all the alkali chlorides can speed up the reduction process of pre oxidized ilmenite, moreover, KCl is the most effective catalyst of the chlorides, while the catalytic effects of LiCl and CsCl are relatively weaker. It seems that the catalytic mechanism of LiCl is different from those of the other alkali chlorides. The cross sectional morphology of the partially reduced pre oxidized ilmenite particles and the distribution of potassium ions within them were examined by means of scanning electronic microscopy and electronic probe microanalysis, respectively, which shows that the reduction proceeds topochemically and the alkali ion enriches at the periphery of the particles.[ 展开更多
关键词 THERMOGRAVIMETRY non-isothermally carbothermic reduction alkali additives pre-oxidized ilmenite
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LRG1 promotes corneal angiogenesis and lymphangiogenesis in a corneal alkali burn mouse model 被引量:1
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作者 Shan Song Jun Cheng +3 位作者 Bing-Jie Yu Li Zhou Hai-Feng Xu Ling-Ling Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期365-373,共9页
AIM:To investigate the potential effect and mechanism of leucine-richα-2-glycoprotein-1(LRG1)on corneal angiogenesis and lymphangiogenesis.METHODS:Corneal neovascularization and lymphatics were induced by establishin... AIM:To investigate the potential effect and mechanism of leucine-richα-2-glycoprotein-1(LRG1)on corneal angiogenesis and lymphangiogenesis.METHODS:Corneal neovascularization and lymphatics were induced by establishing alkali burn mouse model.Immunofluorescence staining was performed to detect the location of LRG1 in cornea tissues and to verify the source of LRG1-positive cells.Corneal whole-mount staining for CD31(a panendothelial cell marker)and lymphatic endothelial hyluronan receptor-1(LYVE-1;lymphatic marker)was performed to detect the growth of blood and lymphatic vessels after local application of exogenous LRG1 protein or LRG1 si RNA.In addition,expressions of the proangiogenic vascular endothelial growth factor(VEGF)related proteins were detected using Western blot analysis.RESULTS:LRG1 was dramatically increased in alkali burned corneal stroma in both the limbal and central areas.LRG1-positive cells in the corneal stroma were mainly derived from Vimentin-positive cells.Local application ofexogenous LRG1 protein not only aggravated angiogenesis but also lymphangiogenesis significantly(P<0.01).LRG1 group upregulated the levels of VEGF and the vascular endothelial growth factor receptor(VEGFR)family when compared with the phosphate-buffered saline(PBS)control group.We also found that LRG1-specific si RNA could suppress corneal angiogenesis and lymphangiogenesis when compared with the scramble si RNA-treated group(P<0.01).CONCLUSION:LRG1 can facilitate corneal angiogenesis and lymphangiogenesis through heightening the stromal expression of VEGF-A,B,C,D and VEGFR-1,2,3;LRG1-specific si RNA can suppress corneal angiogenesis and lymphangiogenesis in corneal alkali burn mice. 展开更多
关键词 leucine-richα-2-glycoprotein-1 ANGIOGENESIS LYMPHANGIOGENESIS CORNEA alkali burn vascular endothelial growth factor
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