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Techniques of copper recovery from Mexican copper oxide ore

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Mining Science and Technology 2009年第1期19卷 45-48页

作者： cao Zhan-fang ZHONG Hong LIU Guang-yi ZHAO Shu-juan Institute of Chemistry and Chemical Engineering Central South University Changsha Hunan 410083 China

Mexican copper ore is a mixed ore containing mainly copper oxide and some copper sulfide that responds well to flotation. The joint techniques of flotation and leaching were studied. The results indicate that an ore containing 19.01% copper could be obtained at a recovery ratio of 35.02% by using sodium sulfide and butyl xanthate flotation. Over 83.33% of the copper oxide can be recovered from the railings by leaching in suitable conditions, such as 1 h stirring at a temperature around 25 ℃with a mixing speed of S00 r/min, an H2SO4 concentration of 1.0 mol/L and a mass ratio of the ore-slurry-liquid to solid （mL/ms） of 3. The overall yield of refined ore after flotation and leaching is over 89.18% of the copper, which is much better than sole flotation or leaching. A copper product containing more than 99.9% copper was obtained by using the process： flotation-agitation leaching- solvent extraction-electro-winning.

关键词： copper oxide ore flotation stirring leaching extraction

Energy Optimized Approach Based on Clustering Routing Protocol for Wireless Sensor Networks

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Energy Optimized Approach Based on Clustering Routing Protoc...

Separation of rhenium from electric-oxidation leaching solution of molybdenite

第25届中国控制与决策会议

作者： LI Jian-qi cao Bin-fang WANG Li Wang Wen-Hu Department of Electronic Engineering Hunan University of Arts and Sciences Department of Physics and Electronics Hunan University of Arts and Sciences

ISBN: (纸本)9781467355339

To realize maximization of the effective coverage area and lifetime for wireless sensor networks monitoring areas, the design of network routing protocol needs to take consideration of both the individual node and the whole network energy consumption. Aiming at the characteristics that node distribution is influenced by natural condition and data can fuse in real environment, as well as signaling overhead in unique uneven EEUC （Energy-Efficient Unequal Clustering protocol）, an improved clustering routing algorithm has been presented, which priority to energy efficiency. First, generate cluster head by random competition in the nodes which have advantage in energy;next determine the internal structure of clusters by calculating dynamically tightness coefficient of each cluster, after that, optimize transmission path between cluster heads through improved multi-objective particle swarm algorithm. Theoretical analysis and simulation results show that new proposed routing protocol can better balance energy consumption improve energy efficiency of the networks and prolong the network lifetime.

关键词： Wireless Sensor Networks routing protocol multi-objective particle swarm optimization energy efficiency

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Journal of Central South University 2013年第8期20卷 2103-2108页

作者： cao Zhan-fang ZHONG Hong JIANG Tao LIU Guang-yi WANG Shuai XIA Liu-yin College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Key Laboratory of Resources Chemistry of Nonferrous Metals of Ministry of Education (Central South University) Changsha 410083 China School of Minerals Processing & Bioengineering Central South University Changsha 410083 China

The separation of rhenium from molybdenum in aqueous solution has always been a problem in hydrometallurgy. The separation of rhenium from the electro-oxidation leachate of molybdenite and its mechanism were investigated. The results show that pH of the leachate significantly affects adsorption rate compared with other experimental parameters. When temperature is 30℃, pH=8, and adsorbing time is 1 h, adsorption rates of rhenium and molybdenum are 93.46% and 3.57%, respectively, and separation factor of D301 resin for rhenium and molybdenum is 169.56. In addition, the separation factor is higher when the initial molybdenum concentration in model solution is increased. The saturated adsorption capacity of D301 resin for molybdenum and rhenium calculated based on simulated results are 4.263 3 mmol/g and 4.235 5 mmol/g, respectively. D301 resin is an effective separation material of rhenium from electric-oxidation leachate of molybdenite. The adsorption kinetics results also show that the adsorption of rhenium is easier than that of molybdenum, and the adsorption process of D301 for rhenium and molybdenum may be controlled by liquid film diffusion.

关键词： rhenium molybdenum separation resin molybdenite

Some remarks on X(6900)

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Chinese Physics C 2021年第10期45卷 25-32页

作者： Qin-fang cao Hao Chen Hong-Rong Qi Han-Qing Zheng Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The analysis of the LHCb data on X(6900)found in the di-J/ψsystem was performed using a momentum-dependent Flatté-like *** use of the pole counting rule and spectral density function sum rule provides consistent evidence that both confining and molecular states are ***,the nature of X(6900)cannot be distinguished if only the di-J/ψexperimental data with current statistics are ***,we found that the lowest state in the di-J/ψsystem likely has the same quantum numbers as X(6900),and X(6900)is probably not interpreted as a J/ψ-ψ(2 S)molecular state.

关键词： X(6900) molecular state tetraquark pole counting rule spectral density function

Structural design of organic battery electrode materials:from DFT to artificial intelligence

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Rare Metals 2023年第10期42卷 3269-3303页

作者： Ting-Ting Wu Gao-Le Dai Jin-Jia Xu fang cao Xiao-Hong Zhang Yu Zhao Yu-Min Qian Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow UniversitySuzhou215123China College of Materials Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou311121China Department of Chemistry and Biochemistry University of Missouri–St.LouisSt.LouisMO63121USA Department of Health Technology Technical University of DenmarkKgs.Lyngby2800Denmark Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systemsand School of PhysicsBeijing Institute of TechnologyBeijing100081China

Redox-active organic materials are emerging as the new playground for the design of new exciting battery materials for rechargeable batteries because of the merits including structural diversity and tunable electrochemical properties that are not easily accessible for the inorganic *** importantly,the sustainability developed by using naturally abundant chemical elements(C,H,N,O and S) makes them as an ideal alternative material for Li-ion batteries(LIBs).However,the identification and screening of proper organic materials is still challenging in the past *** by the artificial intelligence,this review will give a summary of the theoretical design aspects of redox-active organic materials from densityfunctional theory(DFT) to machine learning(ML) methods in the past two decades,with a particular emphasis on the calculation method to predict the chemical/electrochemical stability and *** review will also analyze and discuss the challenges and perspectives for the development of organic battery materials.

关键词： Organic battery Density-functional theory(DFT) High-throughput computation Machine learning(ML)

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-Hao Zeng Shi-Dan Zhu Ying-Hua Luo Wei Shi Yong-Qiang Wang Kun-fang cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Lipid concentration and composition in xylem sap of woody angiosperms from a tropical savanna and a seasonal rainforest

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Plant Diversity 2024年第1期46卷 126-133页

作者： Ling-Bo Huang Xinyi Guan Amy Ny Aina Aritsara Jun-Jie Zhu Steven Jansen Kun-fang cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources Guangxi Key Laboratory of Forest Ecology and ConservationGuangxi UniversityDaxuedong Road 100NanningGuangxi 530004China Institute of Botany Ulm UniversityAlbert-Einstein-Allee 11Ulm89081Germany

Lipids may play an important role in preventing gas embolisms by coating nanobubbles in xylem *** studies on xylem sap lipids have been reported for temperate plants,and it remain unclear whether sap lipids have adaptational significance in tropical *** this study,we quantify the lipid composition of xylem sap for angiosperm species from a tropical savanna(seven species)and a seasonal rainforest(five species)using mass *** found that all twelve species studied contained lipids in their xylem sap,including galactolipids,phospholipids and triacylglycerol,with a total lipid concentration ranging from 0.09 to 0.26 nmol/*** was no difference in lipid concentration or composition between plants from the two sites,and the lipid concentration was negatively related to species’open vessel ***,savanna species showed little variation in lipid composition between the dry and the rainy *** results support the hypothesis that xylem sap lipids are derived from the cytoplasm of individual conduit cells,remain trapped inside individual conduits,and undergo few changes in composition over consecutive seasons.A xylem sap lipidomic data set,which includes 12 tropical tree species from this study and 11 temperate tree species from literature,revealed no phylogenetic signals in lipid composition for these *** study fills a knowledge gap in the lipid content of xylem sap in tropical trees and provides additional support for their common distribution in xylem sap of woody *** appears that xylem sap lipids have no adaptive significance.

关键词： Xylem sap Lipids Tropical savanna Tropical rainforest Vessels

Expression of Endogenous Beta Retroviruses and Hyal-2 mRNA in Immune Organs of Fetuses and Lambs

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Virologica Sinica 2012年第2期27卷 83-92页

作者： Jing-wei Qi Xiao-li Wu Shu-ying Liu Gui-fang cao College of Animal Science and Veterinary Medicine Inner Mongolia Agricultural UniversityHuhhot 010018China Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease Ministry of AgricultureHuhhot 010018China

Endogenous beta retroviruses (enJSRV) are highly homologous with Jaagsiekte sheep retrovirus (exJSRV),this exogenous retrovirus is the aetiological agent of ovine pulmonary adenocarcinoma (OPA). The aim of this study was to clarify the function of enJSRV and the immunological mechanisms of its corresponding antibody, that is undetectable in JSRV-infected ovine serum. The expression of enJSRV envelope protein and Hyal-2 mRNA in immune organs and lungs of ovine fetuses and lambs were analyzed by Real-Time reverse transcription PCR and In Situ Hybridization using specific probes. In Situ Hybridization results indicated that the enJSRV envelope protein and Hyal-2 mRNA were expressed in thymus, spleen, mesenteric lymph nodes and lungs at different times, while no positive signals were detected in the negative controls. On the other hand, results from Real-Time reverse transcription PCR analysis showed that in 130d fetuses and 3d newborn lambs the enJSRV mRNA levels were much higher in organs associated with the immune system than that in lungs, especially in the thymus and spleen, but levels of Hyal-2 mRNA expression was not significantly different in all collected tissue. These results provided evidence from an immunology point of view to understand why the circulating antibodies against exJSRV are undetectable in JSRV-infected ovine, and will help to unravel the pathogenesis of JSRV-infected ovine.

关键词： Ovine enJSRV Hyal-2 In Situ Hybridization Real-Time PCR

Cloning and Expressional Studies of the Voltage-dependent Anion Channel Gene from Brassica rapa L.

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Journal of Integrative Plant Biology 2006年第2期48卷 197-203页

作者： Jiang Wang Li-Da Zhang Kai-Jing ZUO Hong-Mei Qian You-fang cao Ke-Xuan Tang Plant Biotechnology Research Center Fudan-Shanghai Jiao Tong University-Nottingham Plant Biotechnology R＆D Center School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 200030 China State Key Laboratory of Genetic Engineering Fudan-Shanghai Jiao Tong University-Nottingham Plant Biotechnology R＆D Center School of Life Sciences Morgan-Tan International Center for Life Sciences Fudan University Shanghai 200433 China

The voltage-dependent anion channel （VDAC） plays an essential role in the permeability of mltochondrial membrane. In the present study, we isolated a novel VDAC gene （brvdac） based on the assembly of expressed sequence tag sequences from Brassica rapa L. and explored its differential expression patterns In growth, tissues, abiotlc stress, and stress recovery. Results of a tissue-specific expression study in young seedlings Indicated that, of all tissues tested, brvdac expression was the highest in the leaves. Under cold, drought, and salt stresses, brvdac expression showed a transient Increase, and then returned to normal levels when the stress was removed. When plants were exposed to heat shock, there was no Increase in brvdac expression, whereas during recovery a quick and considerable increase in expression was observed. These observations indicate that dissimilar modulations of brvdactranscription may occur when plant cells encounter heat shock and the other three types of stress. In addition, phylogenetic analysis Implied that an earlier duplication of vdac probably occurred before the divergence between monocotyledons and dicotyledons.

关键词： Brassica rapa expression heat shock stress voltage-dependent anion channel.