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Process and kinetics of the selective extraction of cobalt from high-silicon low-grade cobalt ores using ammonia leaching

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 218-227页

作者： Lei Tian ao gong Xuangao Wu Xiaoqiang Yu Zhifeng Xu Lijie Chen Institute of Green Metallurgy and Process Intensification Jiangxi University of Science and TechnologyGanzhou 341000China

An ammonia-based system was used to selectively leach cobalt(Co)from an African high-silicon low-grade Co ore,and the other elemental impurities were inhibited from leaching in this *** process was simple and environmentally *** results revealed that the leaching ratio of Co can reach up to 95.61%using(NH_(4))_(2)SO_(4)as a leaching agent under the following materials and conditions:(NH_(4))_(2)SO_(4)concentration 300 g/L,reductant dosage 0.7 g,leaching temperature 353 K,reaction time 4 h,and liquid-solid ratio 6 mL/*** leaching kinetics of Co showed that the apparent activation energy of Co leaching was 76.07 kJ/mol(i.e.,in the range of 40-300 kJ/mol).This indicated that the leaching of Co from the Co ore was controlled by an interfacial chemical reaction,and then the developed leaching kinetics model of the Co can be expressed as 1-(1-α)^(1/3)=28.01×10~3×r_0^(-1)×C_((NH_(4))_(2)SO_(4))^(1.5)×exp(-76073/8.314 T)×t,whereαis the leaching ratio(%)of Co,r_0 is the average radius(m)of the Co ore particles,T is the temperature(K),and C_((NH_(4))_(2)SO_(4))is the initial reactant concentration(kg/m^(3)).

关键词： ammonia leaching leaching kinetics selective extraction cobalt

Cu^2+-catalyzed mechanism in oxygen-pressure acid leaching of artificial sphalerite

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 910-923页

作者： Lei Tian ao gong Xuan-gao Wu Yan Liu Zhi-feng Xu Ting-an Zhang Institute of Green Metallurgy and Process Intensification Jiangxi University of Science and TechnologyGanzhou 341000China Guangdong Institute of Resources Comprehensive Utilization Guangzhou 510000China State Key Laboratory of Rare Metals Separation and Comprehensive Utilization Guangzhou 510000China Key Laboratory for Ecological Utilization of Multimetallic Mineral Ministry of EducationNortheastern UniversityLiaoning 110819China

The potential autoclave was used to study the catalytic mechanism of Cu^2+during the oxygen pressure leaching process of artificial *** studying the potential change of the system at different temperatures and the SEM–EDS difference of the leaching residues,it was found that in the temperature range of 363–423 K,the internal Cu^2+formed a Cu S deposit on the surface of sphalerite,which hindered the leaching reaction,resulting in a zinc leaching rate of only 51.04%.When the temperature exceeds 463 K,the system potential increases *** increase in temperature leads to the dissolution of the CuS,which is beneficial to the circulation catalysis of Cu^2+.At this time,the leaching rate of Zn exceeds 95%.In addition,the leaching kinetics equations at 363–423 and 423–483 K were *** activation energy of zinc leaching at 363–423 and 423–483 K is 38.66 and 36.25 kJ/mol,respectively,and the leaching process is controlled by surface chemical reactions.

关键词： sphalerite electric potential autoclave copper(II)ions catalyst kinetics activation energy apparent reaction order

New insights and investigation:Morphomolecular notes on the infraciliature,taxonomy,and systematics of pleurostomatid ciliates(Protozoa,Ciliophora),with establishment of a new suborder,two new genera,and three new species

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Zoological Research 2024年第6期45卷 1327-1346页

作者： gong-ao-Te Zhang Teng-Yue Zhang Yong Chi Hong-Bo Pan Zhe Zhang Jia-Chen Zhang Jun-Hua Niu Hong-Gang Ma Khaled A.S.Al-Rasheid Alan Warren Wei-Bo Song Institute of Evolution&Marine Biodiversity and MOE Key Laboratory of Evolution&Marine Biodiversity Ocean University of ChinaQingdaoShandong 266003China Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology CenterQingdaoShandong 266237China Key Laboratory of Zoological Systematics and Application College of Life SciencesHebei UniversityBaodingHebei 071002China Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution Shanghai Ocean UniversityShanghai 201306China Zoology Department College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Life Sciences Natural History MuseumLondon SW75BDUK

Pleurostomatid ciliates,as a highly diverse and widely distributed unicellular eukaryote group,play a crucial role in the cycling of nutrients and energy in microbial food ***,research on pleurostomatids remains insufficient,resulting in a paucity of molecular information and substantial gaps in knowledge of their phylogenetic *** recent years,we investigated pleurostomatid diversity in various Chinese habitats,including their systematic relationships and taxonomic circumscriptions,which were comprehensively analyzed using an integrative morphomolecular *** revealed that:(1)pleurostomatids can be categorized into two suborders,Protolitonotina *** Amphileptina Jankowski,1967;(2)Protolitonotina *** the ancestral pleurostomatid group and includes two genera,Protolitonotus and Heterolitonotus ***.,characterized by right kineties progressively shortened along rightmost full kineties and absence of a left dorsolateral kinety;(3)Heterolitonotus *** an orphan lineage and is defined by an oral slit extending to its dorsal margin;(4)“Protolitonotus clampi”does not group with congeners but instead represents an orphan lineage,thus Novilitonotus *** established to which *** is transferred as Novilitonotus clampi ***.;(5)three new species,Apoamphileptus paraclaparedii ***.,Heterolitonotus rex ***.,***.,and Loxophyllum apohelus ***.,are described;and(6)helices 21es6a to 21es6d within the V4 region of small subunit ribosomal RNA(SSU rRNA)may serve as a useful tool for discriminating *** evolutionary relationships among all main lineages of pleurostomatids are discussed and a key to the identification of pleurostomatid genera is provided.

关键词： Ciliates Integrative approaches New suborder Phylogeny Pleurostomatids

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基于信任模糊评价的P2P访问控制模型

计算机工程 2015年第3期41卷 125-129页

作者：龚翱刘浩湖南人文科技学院信息科学与工程系湖南娄底417000

应用社会信任网络构建的基本原理,给出一种新的P2P访问控制模型。将P2P节点间的信任关系分为直接信任、信任知识和推荐信任3个方面,利用模糊理论对P2P节点进行信任评价,通过扩展多级安全机制实现访问控制,在P2P中的节点间进行交互时,主... 详细信息

应用社会信任网络构建的基本原理,给出一种新的P2P访问控制模型。将P2P节点间的信任关系分为直接信任、信任知识和推荐信任3个方面,利用模糊理论对P2P节点进行信任评价,通过扩展多级安全机制实现访问控制,在P2P中的节点间进行交互时,主体节点根据目标节点的信任等级授予其不同的访问权限,以达到保护P2P网络安全的目标,引入加密与数字签名等安全机制,有效地抑制冒名、窃听和女巫攻击等一系列安全性攻击。在P2P网络中恶意节点比重变化的情况下,对引入该访问控制模型前后的情况进行对比实验,结果表明,引入模型后P2P网络中的节点交互成功率有较大提高。

关键词： P2P网络模糊评价访问控制多级安全授权安全策略

Oxygen pressure acid leaching of artificial sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation

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Journal of Central South University 2020年第6期27卷 1703-1713页

作者： TIAN Lei gong ao WU Xuan-gao XU Zhi-feng ZHANG Ting-an LIU Yan WEI Kui-xian YU Zhan-liang School of Metallurgical and Chemical Engineering Jiangxi University of Science and TechnologyGanzhou 341000China The State Key Laboratory of Pressure Hydrometallurgical Technology of Associated Nonferrous Metal Resources Kunming 650503China Key Laboratory for Ecological Utilization of Multimetallic Mineral Ministry of EducationShenyang 110819China

The mechanism of oxygen pressure acid leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation was investigated in this *** sphalerite was fabricated with varying amounts of iron content via the sintering of ZnS and FeS and used for the pressure acid leaching *** variations in the potential of the pressure leaching system were investigated by using a self-designed potential *** results showed that compared to the non-iron sphalerite,there was a violent redox reaction between the 25.70%Fe-artificial sphalerite and dissolved oxygen during the process of pressure leaching;and the catalytic mechanism was attributed to the redox couple Fe^3+/Fe^2+,where Fe3+oxidizes the H2S gas film and the reduced Fe2+state is subsequently oxidized by the dissolved ***,the effect of temperature,H2SO4 concentration,and oxygen partial pressure on the artificial sphalerite with different iron contents was *** sphalerite samples with iron content were observed to dissolve more easily in sulfuric acid compared to the non-iron ***,the activation energy of artificial sphalerite was observed to be lower in the sample with 25.70%iron content(22.26 kJ/mol)compared to that with no iron(32.31 kJ/mol);and the apparent reaction orders were obtained with respect to H2SO4 concentration(1.10 and 1.36)and oxygen partial pressure(1.29 and 1.41),respectively.A comprehensive kinetic model was developed on the basis of the experimental data and the fitted leaching ratio plot;and the kinetic equations for the leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation were determined.

关键词： leaching mechanism catalyzed by Fe^3+/Fe^2+self-precipitation potential curves artificial sphalerite leaching kinetics activation energy reaction orders

Comparative study on early period of recovery between minimally invasive surgery total knee arthroplasty and minimally invasive surgery-quadriceps sparing total knee arthroplasty in Chinese patients

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Chinese Medical Journal 2008年第15期121卷 1353-1357页

作者： YU Jia-kuo YU Chang-long ao Ying-fang gong Xi WANG Yong-jian WANG Shu XING Xie CHEN Lian-xu JU Xiao-dong Institute of Sports Medicine of Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing 100083 China

Background Different kinds of minimally invasive surgery （MIS） procedures have now been used in total knee arthroplasty （TKA）. Compared with traditional TKA procedure with a long skin incision, clinical studies showed MIS procedures had some advantages. Quadriceps sparing （QS） procedures are the most minimally invasive MIS procedure until now. This study was aimed to find the insertion types for Chinese patients＇ vastus medialis and if the QS procedure had some advantages in patients＇ early recovery. Methods Between February 2006 and May 2007, 120 consecutive patients underwent unilateral primary TKA under general anesthesia, among whom 14 patients were lost to follow-up, the remaining 106 cases were enrolled in this study. Among the 106 cases there were 85 right knees, 21 left knees （15 men and 91 women, with a mean age of 65.1±7.4 years）; osteoarthritis in 97 patients （91.5%） and rheumatoid arthritis in 9 patients （8.5%）. MIS TKA was performed in 49 cases （MIS TKA group）, while MIS-QS TKA in 57 cases （MIS-QS TKA group）. During the operation, the type Ⅰ, Ⅱ and Ⅲ insertions of the vastus medialis for all patients were recorded. Each knee was rated post-operatively according to the Hospital of Special Surgery （HSS） scoring system. Clinical follow-up was undertaken at 1 week, 2, 6, 12 and 24 weeks. Operating time and complications were recorded. Results There was no statistically significant difference between the two groups for gender distribution, age, left or right knee incidence, pre-operative diagnosis, incidence of varus or valgus deformity. Of the 106 cases there was 1 （0.9%） case with a type Ⅰ insertion of the vastus medialis, 4 （3.8%） cases with type Ⅱ insertions, 101 （95.3%） cases with type Ⅲ insertions. The HSS scoring was significantly different between the MIS-QS TKA group and MIS TKA group within the first two weeks post operation. From 2 weeks later to 24 weeks, no significant difference was found. The average operating time was （53.3±12.4） minutes in t

关键词：关节造形术四头肌中国外科手术

高频谐振疲劳机载荷测量误差建模分析及试验夹具优化设计

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中国机械工程 2019年第22期30卷 2675-2682页

作者：高红俐朱楷勇龚澳姜伟浙江工业大学特种装备制造与先进加工技术教育部/浙江省重点实验室

电磁谐振式疲劳裂纹扩展试验过程中,对动态载荷的高精度测量和控制是保证试验结果准确性和系统工作稳定性的重要前提,夹具作为夹持试件和传递载荷的重要机构,对其进行结构优化显得尤为重要。建立了紧凑拉伸(CT)试件连接刚度模型和三自... 详细信息

电磁谐振式疲劳裂纹扩展试验过程中,对动态载荷的高精度测量和控制是保证试验结果准确性和系统工作稳定性的重要前提,夹具作为夹持试件和传递载荷的重要机构,对其进行结构优化显得尤为重要。建立了紧凑拉伸(CT)试件连接刚度模型和三自由度有阻尼振动系统动力学模型,得到了动态载荷测量误差理论表达式;分析了夹具刚度对动态载荷测量误差的影响,设计了不同结构刚度的试件夹具,并通过有限元方法计算其刚度,得到了不同结构夹具对动态载荷测量误差的影响结果;实验验证了优化夹具设计的合理性。

关键词：动态载荷高精度测量疲劳裂纹扩展试验接触刚度夹具优化电磁谐振

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乙醇燃烧过程中氧和氮的迁移历程分析

车用发动机 2015年第2期 18-22页

作者：毛功平李捷辉江苏大学汽车与交通工程学院江苏镇江212013

在乙醇详细化学反应机理的基础上,添加了NOx的详细机理,得到包含64种组分和388个基元反应的乙醇机理。运用Chemkin-Pro软件中的零维单区内燃机HCCI燃烧模型,计算了乙醇燃烧过程中各基元反应的反应速率(ROP)系数,确定了影响各中间产物生... 详细信息

在乙醇详细化学反应机理的基础上,添加了NOx的详细机理,得到包含64种组分和388个基元反应的乙醇机理。运用Chemkin-Pro软件中的零维单区内燃机HCCI燃烧模型,计算了乙醇燃烧过程中各基元反应的反应速率(ROP)系数,确定了影响各中间产物生成的主要基元反应方程式。通过ROP分析,阐明了乙醇燃烧过程中,燃料中的氧,空气中的氧、氮的迁移演变历程,对主要中间产物的前躯体物质进行了分析。研究结果表明:乙醇及其燃烧过程中产生的中间产物促进了HCO,H,C2H3的生成,形成了能促进NOx生成的重要前躯体物质OH和O,导致NOx排放偏高。

关键词：乙醇基元反应数值模拟氮氧化合物

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中西翻译理论比较研究

现代英语 2024年第1期 111-113页

作者：宫傲山东建筑大学山东济南250101

从某种意义上来说,西方的(乃至人类)文明首先应归功于翻译工作者[1]。翻译学需要认真对比中西方的翻译理论。通过对比,可以使读者更好地了解中西方翻译理论的发展情况,以及其在整个人类翻译历史中的地位。通过横向比较不同翻译理论体系... 详细信息

从某种意义上来说,西方的(乃至人类)文明首先应归功于翻译工作者[1]。翻译学需要认真对比中西方的翻译理论。通过对比,可以使读者更好地了解中西方翻译理论的发展情况,以及其在整个人类翻译历史中的地位。通过横向比较不同翻译理论体系,发现二者之间的共同之处和独特之处,以及其抽象理论和实际运用。具体来说,比较可以让读者了解到中西方翻译理论在原则、方法、标准和规则等方面的认识,有许多相似之处。通过比较,翻译理论家们可以互相借鉴,推动翻译研究的进一步发展。

关键词：中西翻译理论相似之处不同之处