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An investigation of oxygen pressure acid leaching of Gacun complex Cu-Pb bulk concentrate 被引量:6
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作者 Xu, Bin Zhong, Hong Jiang, Tao 《Rare Metals》 SCIE EI CAS CSCD 2012年第1期96-101,共6页
The treatment of the Gacun complex Cu-Pb bulk concentrate with high Zn,Ag,etc.,by oxygen pressure acid leaching was studied.The pri-mary copper and leadminerals in the concentrate are tetrahedrite and galena.The treat... The treatment of the Gacun complex Cu-Pb bulk concentrate with high Zn,Ag,etc.,by oxygen pressure acid leaching was studied.The pri-mary copper and leadminerals in the concentrate are tetrahedrite and galena.The treatment of tetrahedrite was rarely studied,and most of silver occurred in themineral too.The optimum operating parameters of oxygen pressure acid leaching were established by conditional tests.Under these parameters,the result of pilot scale test showed that the leaching percentages of copper and zinc were separately as high as 98.9 wt.% and 94.9 wt.%,while lead and silver were transformed into sulfate and sulfide precipitations,respectively.The copper and zinc in lixivium were reclaimed by extraction-electrowinning and purification-electrowinning,respectively,and the lead and silver in the residue were reclaimed separately by carbonate transformation-silicofluoric acid leaching and thiourea leaching. 展开更多
关键词 nonferrous metallurgy synthetic reclaiming oxygen pressure acid leaching complex Cu-Pb bulk concentrate TETRAHEDRITE
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Selective depression mechanism of combination of lime and sodium humate on arsenopyrite in flotation separation of Zn-As bulk concentrate 被引量:4
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作者 Qian WEI Liu-yang DONG +3 位作者 Cong-ren YANG Xue-duan LIU Fen JIAO Wen-qing QIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期668-681,共14页
Lime(CaO)and sodium humate(NaHA)were used as the combined depressant for arsenopyrite pre-treated by CuSO_(4) and butyl xanthate.Micro-flotation tests show that the combined depressant CaO and NaHA achieved the select... Lime(CaO)and sodium humate(NaHA)were used as the combined depressant for arsenopyrite pre-treated by CuSO_(4) and butyl xanthate.Micro-flotation tests show that the combined depressant CaO and NaHA achieved the selective depression of arsenopyrite.Closed-circuit lab-scale test results indicate that the synergistic effect of CaO+NaHA achieved a satisfactory flotation separation of sphalerite and arsenopyrite,for which the Zn grade and recovery of Zn concentrate were 51.21%and 92.21%,respectively.Contact angle measurements,adsorption amount measurements and X-ray photoelectron spectroscopy analysis indicate that the dissolved calcium species(mainly as Ca(2+))were adsorbed on the mineral surfaces,thereby promoting NaHA adsorption.Moreover,the surface of the arsenopyrite absorbed more amount of calcium species and NaHA than that of the sphalerite,thereby accounting for the strong hydrophilic surface of arsenopyrite.The adsorption of NaHA on arsenopyrite was mainly chemical adsorption through its carboxyl groups and Ca atoms,whereas that on sphalerite surface was relatively weak. 展开更多
关键词 SPHALERITE ARSENOPYRITE Zn−As bulk concentrate flotation separation LIME sodium humate
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Analysis of Sulfur Dioxide Concentration Around Bulk Curing Barn Group
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作者 张远盖 蒋胜 +7 位作者 夏春 彭勇 雷晓 张明金 赵锦超 吴磊 陈亮 顾勇 《Agricultural Science & Technology》 CAS 2017年第7期1291-1294,1300,共5页
This study was conducted to analyze the spatial distribution of SO2 mass concentration around baking barn groups. A bulk curing barn group was selected as monitoring object, and SO2 concentration around it was monitor... This study was conducted to analyze the spatial distribution of SO2 mass concentration around baking barn groups. A bulk curing barn group was selected as monitoring object, and SO2 concentration around it was monitored for 2 years. The results showed that the SO2 mass concentration within 30-130 m from the baking barn group exceeded the standard, and with the ground as reference, the SO2 mass concentration at the position 0.9-2.1 m from the ground exceeded the stan- dard. According to the limit value of the SO2 mass concentration for sensitive crops, the SO2 mass concentrations over the standard were concentrated within the range of 200-300 m. On the basis of establishment of "sulfur control", "sulfur reduction" and "sulfur avoiding" system, the SO2 emission status of baking barn groups could be improved from the conversion of heat supply method, the utilization of clean en- ergy and adjustment of crop sensitive period and sensitive area. 展开更多
关键词 bulk curing barn Sulfur Dioxide concentrATION CROPS
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Effect of surface roughness on plasticity of Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_5 bulk metallic glass 被引量:2
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作者 林涛 胡勇 +1 位作者 孔令体 李金富 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1407-1411,共5页
Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glass (BMG) rods were abraded to different surface roughnesses using different types of waterproof abrasive papers and sometimes polishing pastes, and the compressive deformat... Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glass (BMG) rods were abraded to different surface roughnesses using different types of waterproof abrasive papers and sometimes polishing pastes, and the compressive deformation behavior was examined. The results show that the yield strength of the BMG is hardly affected while the compressive plasticity increases from 2.3% to 4.5% with decreasing the surface roughness. Observation of the fractured samples under a scanning electron microscope indicates that the rise in plasticity is accompanied with an increase in shear band density. The results suggest that it is necessary to reduce the surface roughness of BMGs for achieving a large plasticity. 展开更多
关键词 bulk metallic glass surface roughness compressive plasticity stress concentration
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Bulk metallic glasses formed by alloying the Cu_6Zr_5 cluster 被引量:1
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作者 Yanhui Li1), Qing Wang1), Jiang Wu1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of Materials Modification, Dalian University of Technology, Dalian 116024, China 2) International Center of Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2007年第S1期39-42,共4页
The bulk metallic glass formation in the Cu-Zr-M ternary systems by alloying of a binary basic Cu6Zr5 cluster was inves- tigated, where M stands for Sn, Mo, Ta, Nb, Ag, Al and Ti. The Cu6Zr5 cluster is a capped Archim... The bulk metallic glass formation in the Cu-Zr-M ternary systems by alloying of a binary basic Cu6Zr5 cluster was inves- tigated, where M stands for Sn, Mo, Ta, Nb, Ag, Al and Ti. The Cu6Zr5 cluster is a capped Archimedean antiprism that characterizes the local structure of the Cu10Zr7 crystalline phase. This cluster composition almost superposes with Cu-Zr eutectic Cu0.56Zr0.44. A se- ries of alloys along the cluster line (Cu6Zr5)1-xMx were examined for their glass forming abilities. Alloy rods with a diameter of 3 mm were prepared by copper mould suction casting method and analyzed by XRD and thermal analysis. The Cu-Zr based bulk metallic glasses were discovered with minor Nb, Sn, Mo, Ta additions (≤2at%) and Al, Ti, Ag (8at%≤concentration≤9at%). The alloying mechanism was discussed in the light of atomic size, cluster-linking structure and electron concentration factors. 展开更多
关键词 bulk metallic glasses CLUSTER electron concentration atomic size minor-alloying Cu-Zr alloys
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Glass formation of ternary Sm-based Sm-Al-Co bulk metallic glasses
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作者 Jiang Wu1), Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of Materials Modification, Dalian University of Technology, Dalian 116024, China 2) International Center of Materials Physics, Chinese Academy of Sciences, Shenyang, 110016, China 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2007年第S1期50-53,共4页
Ternary Sm-based Sm-Al-Co alloys at specific compositions designed using an e/a- and cluster-related criteria exhibit high glass forming abilities and form bulk glassy rods of 3 mm in diameter by a copper mold suction... Ternary Sm-based Sm-Al-Co alloys at specific compositions designed using an e/a- and cluster-related criteria exhibit high glass forming abilities and form bulk glassy rods of 3 mm in diameter by a copper mold suction-casting method. Four composi- tions of bulk metallic glasses (BMGs) are Sm50Al25Co25, Sm52Al24Co24, Sm54Al23Co23 and Sm56Al22Co22, which all satisfy a constant conduction electron concentration of 1.5. Among them, the BMG exhibiting the largest reduced glass transition temperature (Trg) is Sm50Al25Co25, which reaches 0.648. The glass transition temperature Tg and the onset crystallization temperature Tx of this alloy are respectively 579 and 640 K at a heating rate of 20 K/min. 展开更多
关键词 Sm-based alloys bulk metallic glasses alloy design cluster line electron concentration
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Determination of elastic moduli of composite medium containing bimaterial matrix and non-uniform inclusion concentrations
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作者 Weitao SUN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第1期15-28,共14页
Reservoir porous rocks usually consist of more than two types of matrix materials, forming a randomly heterogeneous material. The determination of the bulk modulus of such a medium is critical to the elastic wave disp... Reservoir porous rocks usually consist of more than two types of matrix materials, forming a randomly heterogeneous material. The determination of the bulk modulus of such a medium is critical to the elastic wave dispersion and attenuation. The elastic moduli for a simple matrix-inclusion model are theoretically analyzed. Most of the efforts assume a uniform inclusion concentration throughout the whole single-material matrix. However, the assumption is too strict in real-world rocks. A model is developed to estimate the moduli of a heterogeneous bimaterial skeleton, i.e., the host matrix and the patchy matrix. The elastic moduli, density, and permeability of the patchy matrix differ from those of the surrounding host matrix material. Both the matrices contain dispersed particle inclusions with different concentrations. By setting the elastic constant and density of the particles to be zero, a double-porosity medium is obtained. The bulk moduli for the whole system are derived with a multi-level effective modulus method based on Hashin's work. The proposed model improves the elastic modulus calculation of reservoir rocks, and is used to predict the kerogen content based on the wave velocity measured in laboratory. The results show pretty good consistency between the inversed total organic carbon and the measured total organic carbon for two sets of rock samples. 展开更多
关键词 heterogeneous porous matrix composite material non-uniform inclusion concentration bulk modulus total organic carbon inversion
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云南某细粒铜钼混合精矿分离工艺优化及工业应用
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作者 姜美光 田小松 +3 位作者 梁泽跃 张军 蔡国民 李诏志 《有色金属(选矿部分)》 CAS 2024年第9期31-37,48,共8页
云南某细粒硫化铜钼混合精矿中主要有价金属元素为铜和钼,矿石中主要矿物为黄铜矿和辉钼矿,脉石矿物主要是石英和云母,铜、钼矿物嵌布粒度较细,与脉石矿物复杂共生。针对混合精矿分离难度大、分离指标较差、药剂单耗用量大、药剂成本高... 云南某细粒硫化铜钼混合精矿中主要有价金属元素为铜和钼,矿石中主要矿物为黄铜矿和辉钼矿,脉石矿物主要是石英和云母,铜、钼矿物嵌布粒度较细,与脉石矿物复杂共生。针对混合精矿分离难度大、分离指标较差、药剂单耗用量大、药剂成本高的现状,结合混合精矿含钼品位的上升,在工艺矿物学研究基础上,开展了选矿试验研究。通过对原有工艺及药剂制度进行优化试验,研制了新型铜钼分离药剂D117和D118,其中D117为铜抑制剂,D118为调整剂。在原矿铜品位20.75%、钼品位0.47%的条件下,采用“抑铜浮钼”、一次粗选、四次精选、一次扫选浮选工艺,获得钼品位45.15%、铜品位1.03%、钼作业回收率85.65%的钼精矿及含钼0.069%、铜品位20.92%、铜作业回收率99.96%的铜精矿,取得了良好的实验室选别指标。将研究成果应用于工业生产后,浮选浓度由18%提升至33%,系统台效由17.4 t/h提高至25.9 t/h,钼作业回收率由66.11%提升至80.55%,年产钼金属由286 t提高至710 t。同时,D117、D118新型小分子药剂的使用取消了水玻璃的添加,并大幅降低了硫化钠用量,硫化钠粗选用量由设计之初125000 g/t降至6000 g/t,降幅达95.20%。通过药剂制度的持续优化,进一步压缩了硫化钠用量,硫化钠单耗由13.4 kg/t降至7.53 kg/t,D117单耗由6.18 kg/t降至3.98 kg/t,在药剂成本大幅度降低的前提下,实现了铜钼分离系统处理量及生产指标的双提升。 展开更多
关键词 细粒 铜钼混合精矿 分离浮选 流程优化 工业应用
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白云鄂博稀土混合精矿工艺矿物学研究 被引量:1
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作者 张玲慧 孙俊燕 +2 位作者 瞿瑞 李文博 张小龙 《有色金属(选矿部分)》 CAS 2024年第5期55-62,72,共9页
目前白云鄂博稀土元素的提取主要采用重污染和高能耗的高温浓硫酸焙烧法,“三废”问题至今没有得到合理的解决,且钍元素作为一种伴生组分难以得到再回收利用。采用自动矿物分析仪、X射线衍射分析、扫描电镜分析、配分分析、光学显微镜... 目前白云鄂博稀土元素的提取主要采用重污染和高能耗的高温浓硫酸焙烧法,“三废”问题至今没有得到合理的解决,且钍元素作为一种伴生组分难以得到再回收利用。采用自动矿物分析仪、X射线衍射分析、扫描电镜分析、配分分析、光学显微镜等分析方法对白云鄂博稀土混合精矿的化学成分、矿物组成、粒度及嵌布特征等进行了工艺矿物学研究,结果表明,该稀土混合精矿REO品位为59.25%,主要稀土矿物由氟碳铈矿、独居石和氟碳钙铈矿组成,主要脉石矿物为磷灰石、萤石、黄铁矿和磁/赤铁矿。在矿物中主要分布的稀土元素为La、Ce、Pr、Nd、Sm、Gd。矿样中矿石-38μm粒级含量占95.92%,氟碳铈矿和独居石单体解离度均在55%以上,矿石整体嵌布特征较为复杂,稀土矿物与萤石和磷灰石的连生关系最为密切。为简化冶金工艺,高效提取稀土元素,提出了采用矿相转化后“浮少抑多”的方法分离氟碳铈矿和独居石的展望,为白云鄂博稀土混合精矿的合理开发应用提供新思路。 展开更多
关键词 白云鄂博稀土混合精矿 工艺矿物学 稀土矿物分离 嵌布特征
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铜铅混合精矿硫酸预氧化-浮选分离参数优化试验研究
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作者 陈海君 谢海云 +4 位作者 祁磊 晋艳玲 宋紫欣 张群丽 刘殿文 《有色金属工程》 CAS 北大核心 2024年第5期95-103,共9页
方铅矿与黄铜矿的分离一直是选矿领域的难点,使用硫酸预氧化可选择性抑制方铅矿表面可浮性,使得两种矿物可浮性产生差异,实现浮选分离。针对铜铅混合精矿硫酸预氧化-浮选分离工艺进行了系统的参数优化。首先,利用单因素试验,分析了预氧... 方铅矿与黄铜矿的分离一直是选矿领域的难点,使用硫酸预氧化可选择性抑制方铅矿表面可浮性,使得两种矿物可浮性产生差异,实现浮选分离。针对铜铅混合精矿硫酸预氧化-浮选分离工艺进行了系统的参数优化。首先,利用单因素试验,分析了预氧化硫酸浓度、温度、时间等关键因素对铜铅混合精矿浮选分离效果的影响;其次,利用正交试验分析,建立了预氧化过程中各影响因素与浮选指标之间的数学模型;通过模型求解,得到最佳预氧化条件为硫酸浓度5 mol/L、时间40 min、温度100℃。最后在上述条件下进行了混合精矿预氧化-浮选闭路试验,获得了铜精矿Cu品位18.03%,Cu回收率94.52%;铅精矿Pb品位47.12%,Pb回收率为91.29%的良好指标,铜铅分离效果显著,对铜铅硫化混合精矿的浮选高效分离提供了一定的借鉴。 展开更多
关键词 铜铅混合精矿 预氧化 铜铅分离 参数优化 正交试验
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普朗铜矿粗颗粒水力浮选实验研究
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作者 罗选旭 封东霞 +4 位作者 童雄 熊宇农 罗亨通 郭明龙 董梦 《矿产保护与利用》 2024年第3期81-88,共8页
针对云南普朗斑岩型铜矿难磨难选的特点,在分析矿石性质的基础上进行粗颗粒水力浮选实验。矿石中的铜主要以黄铜矿形式赋存,钼主要以辉钼矿形式赋存,脉石矿物主要为石英及钠/钙长石。采用HydroFloat水力浮选机对粗颗粒铜钼矿进行混合浮... 针对云南普朗斑岩型铜矿难磨难选的特点,在分析矿石性质的基础上进行粗颗粒水力浮选实验。矿石中的铜主要以黄铜矿形式赋存,钼主要以辉钼矿形式赋存,脉石矿物主要为石英及钠/钙长石。采用HydroFloat水力浮选机对粗颗粒铜钼矿进行混合浮选,达到抛尾目的,减少后续磨矿能耗。HydroFloat水力浮选机在传统流化床的基础上引入气泡,通过复合力场使粗颗粒悬浮后随气泡上升达到分选目的。经水力浮选后,可从铜品位0.39%和含钼0.009%的原矿浮选得到铜品位为0.73%、回收率为95.84%,钼品位为0.016%、回收率为92.05%的铜钼混合粗精矿,抛尾率可达48.80%。 展开更多
关键词 斑岩型铜矿 粗颗粒 水力浮选 铜钼混合粗精矿
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二氧化铀产品堆密度提升研究 被引量:1
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作者 冯博能 冯鹏程 龚道坤 《铀矿冶》 CAS 2024年第2期53-57,共5页
为提升二氧化铀产品品质,分析了铀纯化新老生产线二氧化铀产品的堆密度,发现铀纯化老生产线产品堆密度均高于新生产线产品的堆密度。分析其主要原因是新生产线结晶剂浓度波动较大,导致三碳酸铀酰铵的结晶效果变差,晶体粒径变小,进而影... 为提升二氧化铀产品品质,分析了铀纯化新老生产线二氧化铀产品的堆密度,发现铀纯化老生产线产品堆密度均高于新生产线产品的堆密度。分析其主要原因是新生产线结晶剂浓度波动较大,导致三碳酸铀酰铵的结晶效果变差,晶体粒径变小,进而影响了晶体煅烧效果和二氧化铀产品堆密度。通过将新老生产线碳酸铵配制岗位合并,统一、就近供应结晶剂,对回收的碳酸铵溶液进行增浓,并用蒸汽冲洗输送管道,解决了新生产线结晶效果波动问题,使新生产线二氧化铀产品平均堆密度提升了5.71%,平均每桶产品净重提升了4.73%,并提升了二氧化铀的产品品质。 展开更多
关键词 二氧化铀 堆密度 每桶产品净重 结晶剂 浓度控制
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Cycling performance of layered oxide cathode materials for sodium-ion batteries
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作者 Jinpin Wu Junhang Tian +1 位作者 Xueyi Sun Weidong Zhuang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1720-1744,共25页
Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the applicat... Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the application prospects of batteries.However,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application requirements.Therefore,this review proposes several strategies to address these challenges.First,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion doping.Second,homogeneous surface coating and concentration gradient modification are reviewed.In addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are proposed.Finally,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials. 展开更多
关键词 sodium-ion battery layered oxide materials cycling performance bulking doping surface coating concentration gradient mixed structure high-entropy
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某混合精矿铜钼分离浮选试验研究
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作者 郭潇文 赵澳 +3 位作者 章旭福 梁泽跃 张军 蒋丛国 《云南冶金》 2024年第4期71-78,共8页
针对云南某铜钼混合精矿特点,在矿石工艺矿物学研究的基础上,开展单因素条件试验研究。探索优化浮选工艺、药剂制度、筛选出对辉钼矿捕收效果较煤油更优的新型钼捕收剂M1。试验结果表明:在最佳药剂条件下,使用新型钼捕收剂M1,可获得精... 针对云南某铜钼混合精矿特点,在矿石工艺矿物学研究的基础上,开展单因素条件试验研究。探索优化浮选工艺、药剂制度、筛选出对辉钼矿捕收效果较煤油更优的新型钼捕收剂M1。试验结果表明:在最佳药剂条件下,使用新型钼捕收剂M1,可获得精矿钼品位46.330%,钼作业回收率87.69%,铜精矿作业回收率99.83%的较好指标。 展开更多
关键词 混合精矿 铜钼分离 辉钼矿 捕收剂 条件试验
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SBR法处理生活污水时非丝状菌污泥膨胀的发生与控制 被引量:37
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作者 陈滢 彭永臻 +2 位作者 刘敏 甘一萍 王淑莹 《环境科学学报》 CAS CSCD 北大核心 2005年第1期105-108,共4页
采用序批式活性污泥法(SBR)处理实际生活污水.研究了低溶解氧条件下,有机负荷对污泥膨胀的影响和突然降温对污泥沉降性能的影响.低溶解氧条件下,当有机负荷为0 20kg·(kg·d)-1和0 26kg·(kg·d)-1时,活性污泥中虽然有... 采用序批式活性污泥法(SBR)处理实际生活污水.研究了低溶解氧条件下,有机负荷对污泥膨胀的影响和突然降温对污泥沉降性能的影响.低溶解氧条件下,当有机负荷为0 20kg·(kg·d)-1和0 26kg·(kg·d)-1时,活性污泥中虽然有丝状菌存在,但并没有发生污泥膨胀.有机负荷达到0 57kg·(kg·d)-1时,菌胶团过量生长,发生非丝状菌污泥膨胀.提高溶解氧,降低有机负荷可使污泥沉降性能恢复正常.突然降温,也会导致非丝状菌污泥膨胀.恢复温度后,膨胀现象可得到控制.非丝状菌污泥膨胀除了没有丝状菌过量增殖外,还具有污泥有粘性,泥水混合液难过滤的特点. 展开更多
关键词 非丝状菌污泥膨胀 有机负荷 污泥沉降性能 SBR法 生活污水 溶解氧 序批式活性污泥法 处理 过量 正常
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黄土高原半干旱区不同封育年限草地生态系统碳密度 被引量:8
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作者 高阳 马虎 +3 位作者 程积民 安雨 刘伟 陈奥 《草地学报》 CAS CSCD 北大核心 2016年第1期28-34,共7页
本研究以云雾山国家级自然保护区典型草原为研究对象,分析了不同封育年限长芒草(Stipa bungeana)草地生态系统碳密度及其库间分配规律。主要结果如下:放牧和封育5年、9年、15年、22年、25年、30年的草地生态系统碳密度变化范围为212.... 本研究以云雾山国家级自然保护区典型草原为研究对象,分析了不同封育年限长芒草(Stipa bungeana)草地生态系统碳密度及其库间分配规律。主要结果如下:放牧和封育5年、9年、15年、22年、25年、30年的草地生态系统碳密度变化范围为212.72-350.42 Mg C·hm^-2,其中,封育30年草地最高,放牧草地最低,且显著低于各封育草地(P〈0.05)。草地植被碳密度以封育15年最高,达到15.65 Mg C·hm^-2,放牧草地最低,仅为7.82 Mg C·hm^-2。在库间分配上,根系碳密度所占平均比例达到82.56%。草地土壤碳密度在204.90-337.36 Mg C·hm^-2之间变化,随封育年限的延长持续增加,封育草地土壤碳密度是放牧牧草地的2.33-2.64倍。以上结果表明,封育可显著提高黄土高原半干旱区草地生态系统碳密度,但过长时间的封育阻碍草地的更新和固碳潜力发挥,合理利用才能促进草地生态系统持续健康发展。 展开更多
关键词 封育 生物量 碳含量 土壤容重
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Cu基Cu-Zr-Al块体非晶合金的成分设计 被引量:16
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作者 王清 王英敏 +3 位作者 羌建兵 张新房 王德和 董闯 《金属学报》 SCIE EI CAS CSCD 北大核心 2004年第11期1183-1188,共6页
利用变电子浓度经验判据,从Cu-Zr亚组元体系中的最深共晶点Cu61.8Zr38.2和次深共晶点Cu56Zr44出发,连接第三组元Al,建立(Cu81.8Zr38.2)1-xAlx和(Cu56Zr44)1-xAlx变电子浓度线.电子浓度在1.24—1.30的(Cu61.8Zr38.2)1-xAlx合金可通过铜... 利用变电子浓度经验判据,从Cu-Zr亚组元体系中的最深共晶点Cu61.8Zr38.2和次深共晶点Cu56Zr44出发,连接第三组元Al,建立(Cu81.8Zr38.2)1-xAlx和(Cu56Zr44)1-xAlx变电子浓度线.电子浓度在1.24—1.30的(Cu61.8Zr38.2)1-xAlx合金可通过铜模吸铸法形成直径为3 mm的块体非晶;对于(Cu56Zr44)1xAlx系列合金,块体非晶形成的电子浓度区间为1.28—1.36.热分析结果表明,每条变电子浓度线上块体非晶合金的热稳定性和玻璃形成能力随电子浓度增大而增加.其中, (Cu61.8Zr38.2)1-xAlx变电子浓度线上的非晶合金Cu58.1Zr35.9A16(e/a=1.3)具有最高的热稳定性和最大的玻璃形成能力,其特征参数Tg=760 K,Tg/Ti=0.648,皆高于已报道的最优成分Cu55Zr40Al5(Tg=722 K,Tg/Ti=0.614). 展开更多
关键词 块体金属玻璃 Cu—Zr—Al合金 电子浓度
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Zr基大块非晶合金成分的等电子浓度和等原子尺寸判据 被引量:13
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作者 陈伟荣 王英敏 +3 位作者 羌建兵 徐卫平 王德和 董闯 《材料研究学报》 EI CAS CSCD 北大核心 2002年第2期219-224,共6页
制备了 6种合金Zr65.5A15.6Ni6.5Cu22.4,Zr65.3Al6.5Ni8.2Cu20,Zr65Al7.5Ni10Cu17.5,Zr64.8Al8.3Ni11.4Cu15.5,Zr64.5Al9.2Ni13.... 制备了 6种合金Zr65.5A15.6Ni6.5Cu22.4,Zr65.3Al6.5Ni8.2Cu20,Zr65Al7.5Ni10Cu17.5,Zr64.8Al8.3Ni11.4Cu15.5,Zr64.5Al9.2Ni13.2Cu13.1 和 Zr63.8Al11.4Ni17.2Cu7.6,共晶成分位于合金 Zr64.5Al9.2Ni13.2Cu13.1 和合金 Zr63.8Al11.4Ni17.2Cu7.6的成分之间 这6种合金均显示了非晶相的形成和较宽的过冷液相区范围 ATx 值.以及较大的约化玻璃转变温度 Trg 值,除合金Zr63.8Al11.4Ni17.2Cu7.6的Tx值为 87 K外.其余5种成分合金的Tx值均在 97 K以上.最宽的达 105 K,表明这 6种合金是一个具有大玻璃形成能力和高热稳定性的非晶合金系列,合金Zu63.8Al11.4Ni17.2Cu17.6是 6种合金中玻璃形成能力和热稳定性最高的.其 Tg、Tx和Trg值最高Inoue非品合金Zr65Ak7.5Ni10Cu17.5并不是最佳非晶成分,提出以等电子浓度和等原子尺寸规律作为设计大块非晶合金成分的判据。 展开更多
关键词 ZR基大块非晶合金 成分 等电子浓度 等原子尺寸 判据 锆基合金
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玻利维亚某铜钼矿浮选试验研究 被引量:7
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作者 王振 肖军辉 +1 位作者 耿志强 徐龙华 《有色金属(选矿部分)》 CAS 北大核心 2014年第3期26-29,共4页
对玻利维亚某地铜钼矿,通过大量的条件试验,最终确定了铜钼混合浮选工艺的最佳磨矿条件和药剂条件及流程,获得铜、钼品位分别为24.89%和0.52%的铜钼混合精矿,其中铜、钼回收率分别为87.11%和72.51%,为后续的铜钼分离创造了较佳的条件。
关键词 铜钼矿 混合浮选 混合精矿 捕收剂
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某含滑石铜钼混合精矿的分离 被引量:7
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作者 王振 钱云楼 +2 位作者 徐龙华 肖军辉 傅开彬 《矿冶工程》 CAS CSCD 北大核心 2015年第1期51-53,60,共4页
对某含滑石铜钼混合精矿进行了铜钼分离试验研究。通过一粗两扫七精闭路浮选流程获得了钼品位34.46%、钼作业回收率88.97%的钼精矿和铜品位23.52%、回收率99.83%的铜精矿。通过辉钼矿-滑石反浮选分离探索试验获得钼品位45.16%、钼作业... 对某含滑石铜钼混合精矿进行了铜钼分离试验研究。通过一粗两扫七精闭路浮选流程获得了钼品位34.46%、钼作业回收率88.97%的钼精矿和铜品位23.52%、回收率99.83%的铜精矿。通过辉钼矿-滑石反浮选分离探索试验获得钼品位45.16%、钼作业回收率97.91%的最终钼精矿。 展开更多
关键词 混合精矿 铜钼分离 滑石 反浮选
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