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Effect and mechanism of siderite on reverse flotation of hematite

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 373-379页

作者： Wan-zhong Yin dong Li Xi-mei Luo jin Yao Qian-yu Sun College of Resources and Civil Engineering Northeastern University College of Zijin Mining Fuzhou University Faculty of Land Resource Engineering Kunming University of Science and Technology

The effects of siderite on reverse flotation of hematite were investigated using micro flotation, adsorption tests, and Fourier transform infrared spectroscopy. The flotation results show that interactions between siderite and quartz are the main reasons that siderite significantly influences the floatability. The interactions are attributed to dissolved siderite species and fine siderite particles. The interaction due to the dissolved species is, however, dominant. Derjaguin-Landau-Verwey-Overbeek（DLVO） theoretical calculations reveal that adhesion on quartz increases when the siderite particle size decreases and that fine particles partly influence quartz floatability. Chemical solution calculations indicate that the dissolved species of siderite might convert the surface of active quartz to CaCO_3 precipitates that can be depressed by starch. The theoretical calculations are in good agreement with the results of adsorption tests and FTIR spectroscopy and explain the reasons why siderite significantly influences reverse flotation of hematite.

关键词： hematite siderite reverse flotation solution chemistry

Optimal Deployment Patterns for k-Coverage and k-Connectivity 3D WSNs in Underground Tunnel

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Journal of Electronic Science and Technology 2017年第3期15卷 303-312页

作者： Wang-Sheng Fang Gao-Xiang Lei zhong-dong Hu jin Li Faculty of Information Engineering Jiangxi University of Science and technology Ganzhou 341000

In this paper,we first model the mining structure as a arched shape in terms of the tunnel *** on the regularly placement of nodes in that model,a set of deployment patterns for seamless coverage and k-connectivity is proposed,i.e.1-and ***,we figure out the maximum horizontal distance of tangent plane to determine the placement of nodes for k-coverage（k=1,2）.Besides,the mathematical relations between the communication radius and the sensing radius are derived,when the network keeps k-coverage（k=1,2） and k-connectivity（k=2,3） under certain regularity constrains for various ***,we demonstrate the optimality of several approaches that we have proposed in the aspect of energy consumption and network lifetime.

关键词： Index Terms--Arched mine tunnel coverage,connectivity deployment patterns maximum horizontaldistance wireless sensor network (WSN).

Urokinase perfusion prevents intrahepatic ischemic-type biliary lesion in donor livers

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World Journal of Gastroenterology 2009年第28期15卷 3538-3541页

作者： Ren Lang Qiang He zhong-Kui jin dong-dong Han Da-Zhi Chen Department of Hepatobiliary Surgery BeijingChaoyang Hospital Capital Medical University Beijing Centerfor Organ Transplantation Beijing 100020 China

AIM： To evaluate whether urokinase perfusion of non-heart-beating cadaveric donor livers reduces the incidence of intrahepatic ischemic-type biliary lesions （IITBLs）. METHODS： A prospective study was conducted to investigate potential microthrombosis in biliary microcirculation when non-heart-beating cadaveric livers were under warm or cold ischemic conditions. The experimental group included 140 patients who underwent liver transplantation during the period of January 2006 to December 2007, and survived for more than 1 year. The control group included 220 patients who received liver transplantation between July 1999 and December 2005 and survived for more than 1 year. In the experimental group, the arterial system of the donor liver was perfused twice with urokinase during cold perfusion and after trimming of the donor liver. The incidence of IITBLs was compared between the two groups. RESULTS： In the control group, the incidence of IITBLs was 5.9% （13/220 cases） after 3-11 mo of transplantation. In the experimental group, two recipients （1.4%） developed IITBLs at 3 and 6 mo after transplantation, respectively. The difference in the incidence between the two groups was statistically significant （P 〈 0.05）. CONCLUSION： Double from non-heart-beating perfusion of cadaveric livers donors with urokinase may reduce the incidence of IITBLs.

关键词： Cadaver donor Liver transplantation Ischemic-type biliary lesion Urokinase

Progress in the Research and Manufacture of GH4169 Alloy

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Journal of Iron and Steel Research International 2015年第8期22卷 657-663页

作者： jin-hui DU Xu-dong LU Qun DENG zhong-nan BI Beijing Key laboratory of Advanced High Temperature Materials Central Iron and Steel Research Institute

GH4169 alloy has been widely used in fields such as aviation, aerospace, and petrochemical, because of its excellent combination of mechanical and processing properties. These properties include good high-temperature strength, excellent creep and fatigue resistance, and good processing and welding performance. The requirement for high performance, high reliability, and long service life of modem engines has led to the incentive to develop GH4169 alloys with improved performance, such as increased temperature-bearing capacity, improved creep endurance, and better fatigue resistance. Advances during the past thirty years in ba- sic research and industrial technology related to GH4169 alloy were systematically summarized, including advances in alloy modi- fication, melting process optimization, and hot deformation technology.

关键词： GH4169 triple-melt cogging radial forging isothermal forging

Ag_(24)Au cluster decorated mesoporous Co_(3)O_(4)for highly selective and efficient photothermal CO_(2)hydrogenation

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Nano Research 2022年第6期15卷 4965-4972页

作者： Yan Xiong Xu Liu Yi Hu dong Gu Minghang Jiang Zuoxiu Tie zhong jin MOE Key Laboratory of Mesoscopic Chemistry MOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Suzhou Tierui New Energy Technology Co.Ltd. Suzhou 215228China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be ***,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)*** orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and ***,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature *** Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)*** mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)*** work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.

关键词： mesoporous Co_(3)O_(4) Ag_(24)Au clusters CO_(2)hydrogenation photothermal catalytic

Expansion and expression diversity of FAR1/FRS-like genes provides insights into flowering time regulation in roses

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Plant Diversity 2021年第2期43卷 173-179页

作者： Mi-Cai zhong Xiao-dong Jiang Wei-Hua Cui jin-Yong Hu CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Roses are important horticultural plants with enormous diversity in flowers and flowering ***,molecular regulation of flowering time variation in roses remains poorly ***,we report an expansion of the FAR1/FRS-like genes that correlates well with the switch to prostrate-toerect growth of shoots upon flowering in Rosa wichuraiana‘Basye's Thornless'(BT).With the availability of the high-quality chromosome-level genome assembly for BT that we developed recently,we identified 91 RwFAR1/FRS-like genes,a significant expansion in contrast to 52 in Rosa chinensis‘Old Blush’(OB),a founder genotype in modern rose *** FAR1/FRS-like proteins feature distinct variation in protein domain *** dispersed expansion of RwFAR1/FRS-like genes occurred specifically in clade I and II and is significantly associated with transposon insertion in *** of the RwFAR1/FRS-like genes showed relatively higher expression level than their corresponding orthologs in ***1/FRS-like genes regulate light-signaling processes,shade avoidance,and flowering time in Arabidopsis ***,the expansion and duplication of RwFAR1/FRS-like genes,followed by diversification in gene expression,might offer a novel leverage point for further understanding the molecular regulation of the variation in shoot-growth behavior and flowering time in roses.

关键词： Rose FAR1/FRS-Like genes Gene family expansion Flowering time Shoot growth behavior

Synthesis and formation mechanism of micro/nano flower-like MgCO_3·5H_2O

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 304-310页

作者： Wan-zhong Yin Yu-lian Wang Qiang-dong Ji jin Yao Ying Hou Lei Wang Wen-xing zhong School of Resources & Civil Engineering Northeastern University Mining Metallurgy &Materials Research Institute General Research Institute for Nonferrous Metals Beijing

Micro/nano magnesium carbonate pentahydrate（MgCO3 ·5H2 O） with flower-like morphology was synthesized using magnesite as a substrate and potassium dihydrogen phosphate as an additive. The synthesized samples were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry and differential scanning calorimetry. The influence of pyrolysis time on crystal morphology was explored. The formation mechanism was investigated on the basis of the characterized results and the crystal structure of MgCO3 ·5H2 O. The results showed that the flower-like MgCO3 ·5H2 O was 1.5-3.0 μm in length and 100-500 nm in diameter and was successfully obtained with a pyrolysis time of 30 min. The formation mechanism of flower-like MgCO3 ·5H2 O is suggested to be the selective adsorption of potassium dihydrogen phosphate on the surface. The process of flower-like crystal growth is as follows： amorphous nanoparticles formation, acicular and rod monocrystal formation, flower-like monocrystal formation, and flower-like polymers（MgCO3 ·5H2 O） crystallization. In the MgCO3 ·5H2 O crystal, the magnesium ion presents two different octahedral coordinations corresponding to2 26 Mg（H O）＋and2 2 2 4 23 [Mg（H O）（CO） ]--, and the chemical formula of the crystal is2 2 6 2 4 23 Mg（H O） Mg（H O）（CO）2.

关键词： magnesium carbonate hydrates synthesis morphology crystal growth

Mixed Rescaling Model and Direct Photon Production

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Chinese Physics Letters 1996年第3期13卷 165-167页

作者： LIN zhong-jin Department of Physics Xiamen UniversityXiamen 361005 CCAST(World Loboratory) P.O.Box 8730Beijing 100080

Using the mixed rescaling model,the main features of the European Muon Collaboration eifec t can be *** the ratio of cross sections,free proton(p)-bound nucleon of Iron(Fe)to free proton-free proton,for large-P_(T) di... 详细信息

关键词： scaling explained free

有机金属卤化物钙钛矿CH_(3)NH_(3)PbBr_(3)的各向异性Rashba效应

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原子与分子物理学报 2025年第6期42卷 153-158页

作者：蔡锦鸿余达明周贤中广东工业大学集成电路学院广州510006

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出... 详细信息

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出强烈的各向异性.Rashba带分裂的最大系数可达2.0 eV?,并通过分析能级和电荷密度分布解释了Rashba效应的形成机制.这些研究结果有助于深化对CH_(3)NH_(3)PbBr_(3)性质的理解,同时为其在自旋电子学领域的潜在应用提供了理论基础.

关键词：钙钛矿 CH_3NH_3PbBr_3 密度泛函理论自旋轨道耦合

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