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Optimization of submerged entry nozzle parameters for ultra-high casting speed continuous casting mold of billet

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Journal of Iron and Steel Research International 2022年第1期29卷 44-52页

作者： Pei Xu Yong-zhi Zhou Deng-fu chen Mu-jun Long Hua-mei Duan Laboratory of Metallurgy and Materials College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Controlling the flow behavior in the mold in an appropriate way is the basis for realizing the billet ultra-high speed continuous *** on the new proposed physical water modeling experiment considering the effects of solidified shell and hydrostatic pressure,the flow behavior in the mold with cross section of 160 mm 9160 mm during continuous casting of billet is regulated by optimizing the inner diameters and immersion depths of submerged entry nozzle at the ultra-high casting speeds of 5.0–6.5 m/*** results show that under the premise of no slag entrainment,as well as uniform coverage and keeping good fluidity of liquid slag layer on the top free surface of the fluid in the mold,the appropriate parameters of submerged entry nozzle under the ultra-high casting speed of billet are 50 mm in inner diameter,95 mm in outer diameter and 180 mm in immersion *** on the basis of the obtained parameters of submerged entry nozzle,it can be known that the reasonable ranges of level fluctuation and impacting depth of the stream in the mold are about 0.82-1.11 and 593-617 mm,respectively.

关键词： Ultra-high casting speed Billet continuous casting Submerged entry nozzle Physical water modeling Flow behavior

Effective alleviation of Cd stress to microbial communities in mining reclamation soils by thiourea-modified biochar amendment

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Pedosphere 2022年第6期32卷 866-875页

作者： Yanfeng ZHU Jing MA fu chen Ruilian YU Gongren HU Yongjun YANG Engineering Research Center of Ministry of Education for Mine Ecological Restoration China University of Mining and TechnologyXuzhou 221008(China) College of Chemical Engineering Huaqiao UniversityXiamen 361021(China) Low Carbon Energy Institute China University of Mining and TechnologyXuzhou 221008(China)

Reclaimed soils in mining area usually display low fertility and present Cd *** amendment of modified biochar effectively fixes Cd in soils,enhances soil fertility,and reduces Cd stress in soil ***,the effect of thiourea-modified biochar(TBC)on microbial adaptability to Cd stress in mining reclamation soils is still *** present work studied the Cd immobilization and microbial community changes in a mining reclamation soil displaying extreme Cd contamination under TBC *** results indicated that the amendment of TBC significantly enhanced(Pfuture.

关键词： available phosphorus bacterial structure Cd immobilization enzyme activity toxicity characteristic leaching procedure-extracable Cd

Temperature-insensitive microwave absorption of TiB2-Al_(2)O_(3)/MgAl_(2)O_(4) ceramics based on controllable electrical conductivity

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Science China(Technological Sciences) 2021年第6期64卷 1250-1263页

作者： LIU XiongZhang ZHANG Sealing LUO Hui chen fu LI DongMeng WANG Xian GONG RongZhou School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China College of Mechanical and Electronic Engineering Northwest Agriculture and Forestry UniversityYangling 712100China School of Information Science and Engineering Wuhan University of Science and TechnologyWuhan 430081China

The design of the high-temperature microwave absorbing materials (MAMs) with temperature-insensitive and considerable microwave absorption (MA) capacity is a tremendous *** B2-Al_(2)O_(3)/Mg Al_(2)O_(4) MAMs are prepared by the spark plasma sintering (SPS).further,the influences of the Al_(2)O_(3) content on the flexural strength,thermal stability,high-temperature electrical conductivity,dielectric and MA properties are *** results show that the Al_(2)O_(3) content is associated with flexural strength,high-temperature thermal stability,electrical conductivity,dielectric and MA ***,the temperatureinsensitive and considerable MA properties with the minimum reflection loss (RLmin) ranging from -19.4 to -14.3 dB and the effective absorption bandwidth (EAB,RL<-5 dB) of 3.19–3.55 GHz are attained at 25°C–700°C in 8.2–12.4 GHz as the Al_(2)O_(3) content increases from 70.6 wt%to 80.6 wt%.This is ascribed to the compensating effect of the positive and negative temperature coefficient materials on the high-temperature electrical conductivity as well as the co-play of the dipolar and interfacial polarization at elevated ***,Ti B2-Al_(2)O_(3)/Mg Al_(2)O_(4) ceramics exhibit the ideal prospect as the high-temperature MAMs.

关键词： titanium boride aluminium oxide magnesium-aluminate spinel high-temperature electrical conductivity temperatureinsensitive microwave absorption properties

Cropping Pattern Modifications Change Water Resource Demands in the Beijing Metropolitan Area

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Journal of Integrative Agriculture 2012年第11期11卷 1914-1923页

作者： HUANG Jing Bradley G Ridoutt XU Chang-chun ZHANGHai-lin chen fu College of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China Commonwealth Scientific and Industrial Research Organisation (CSIRO) Sustainable Agriculture Flagship Victoria 3169 Australia

Adequate freshwater supply has become an issue of increasing local and international concern. Reducing water use in agriculture, which is the largest water using sector of the economy, is both important and urgent. The aim of this paper was to quantify how recent cropping pattern changes have influenced water resources in the great Beijing metropolitan area, an expanding megacity which also includes rural counties. Crop production affects blue water use through water consumption and water pollution, the latter assessed here using a critical dilution method. From 1990 to 2010, the total blue water used by crop production declined due to a decrease in overall cropped area, initially in response to local government policies favouring urban development. However, the average blue water use per hectare increased from 2 112 m3 ha-~ yr-~ in 1990 to 2 764 m3 ha-1 yr-1 in 2003, largely as the result of a transition from cereal to vegetable crops, and in particular an increase in intensively managed plastic and glass covered vegetable production systems. Current policies aim to conserve agricultural land, in the interests of food security, and to stimulate cereal production systems with higher ecosystem services provision. As such, in 2010 the average blue water use was 2 425 m3 ha-~ yr-l. These results demonstrate that cropping pattern changes in peri-urban regions and rural communities surrounding the Beijing metropolitan area can have a substantial impact on water resources. They also highlight the tradeoffs between food production and urban and industrial water supply and the need for integrated policy development.

关键词： blue water use water consumption water pollution cropping pattern adjustment peri-urban food production

Epidemiology,management,and economic evaluation of screening of gallstone disease among type 2 diabetics:A systematic review

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World Journal of Clinical Cases 2015年第7期3卷 599-606页

作者： Lujie chen Yu-Ting Peng fu-Li chen Tao-Hsin Tung Faculty of Public Health College of MedicineFu-Jen Catholic University Department of Medical Research and Education Cheng-Hsin General Hospital

The knowledge of gallstone disease(GSD) is crucial to manage this condition when organizing screening and preventive strategies and identifying the appropriated clinical therapies. Although cholecystectomy still be the gold standard treatment for patients with symptomatic GSD, expectant management could be viewed as a valid therapeutic method for this disorder. If early treatment of GSD decreases the morbidity or avoids further cholecystectomy, it may save clinical care costs in later disease periods sufficiently to offset the screening and early treatment costs. In addition, whether routine screening for GSD is worthwhile depends on whether patients are willing to pay the ultrasonography screening cost that would reduce the risk of cholecystectomy. In this review we discuss the epidemiology, management, and economic evaluation of screening of GSD among type 2 diabetics.

关键词： Gallstone disease Epidemiology Management Economic evaluation Type 2 diabetes

A novel biomedical titanium alloy with high antibacterial property and low elastic modulus

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Journal of Materials Science & Technology 2021年第22期81卷 13-25页

作者： Diangeng Cai Xiaotong Zhao Lei Yang Renxian Wang Gaowu Qin Da-fu chen Erlin Zhang Key Laboratory for Anisotropy and Texture of Materials Education Ministry of ChinaSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Research Center for Metallic Wires Northeastern UniversityShenyang 110819China Laboratory of Bone Tissue Engineering Beijing Laboratory of Biomedical MaterialsBeijing Research Institute of Orthopaedics and TraumatologyBeijing Jishuitan HospitalBeijing 100035China

β-type titanium alloys have attracted much attention as implant materials because of their low elastic modulus and high strength,which is closer to human bones and can avoid the problem of stress fielding and extend the lifetime of ***,other issues,such as the infection or inflammation postimplantation,still trouble the titanium alloy's clinical *** this paper,we developed a novel nearβ-titanium alloy(Ti-13Nb-13Zr-13Ag,TNZA)with low elastic modulus and strong antibacterial ability by the addition of Ag element followed by proper microstructure controlling,which could reduce the stress shielding and bacterial infections *** microstructure,mechanical properties,corrosion resistance,antibacterial properties and cell toxicity were studied using SEM,electrochemical testing,mechanical test and cell *** results have demonstrated that TNZA alloy exhibited an elastic modulus of 75-87 GPa and a strong antibacterial ability(up to 98%reduction)and good ***,it was also shown that this alloy's corrosion resistance was better than that of *** the results suggested that Ti-13Nb-13Zr-13Ag might be a competitive biomedical titanium alloy.

关键词： Low Young’s modulus Antibacterial property Titanium alloy Compatibility Antibacterial titanium alloy

Rock physics and seismic reflectivity parameterization and amplitude variation with offsets inversion in terms of total organic carbon indicator

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Petroleum Science 2023年第4期20卷 2092-2112页

作者： Song-He Yu Zhao-Yun Zong Xing-Yao Yin Kun Lang fu-Bin chen School of Geosciences China University of Petroleum(East China)QingdaoShandong266580China Pilot National Laboratory for Marine Science and Technology(Qingdao) QingdaoShandong266580China Shandong Provincial Key Laboratory of Deep Oil and Gas QingdaoShandong266580China

Total organic carbon (TOC) prediction with elastic parameter inversions has been widely used in the identification and evaluation of source rocks. However, the elastic parameters used to predict TOC are not only determined by TOC but also depend on the other physical properties of source rocks. Besides, the TOC prediction with the elastic parameters inversion is an indirect method based on the statistical relationship obtained from well logs and experiment data. Therefore, we propose a rock physics model and define a TOC indicator mainly affected by TOC to predict TOC directly. The proposed rock physics model makes the equivalent elastic moduli of source rocks parameterized by the TOC indicator. Combining the equivalent elastic moduli of source rocks and Gray’s approximation leads to a novel linearized approximation of the P-wave reflection coefficient incorporating the TOC indicator. Model examples illustrate that the novel reflectivity approximation well agrees with the exact Zoeppritz equation until incident angles reach 40°. Convoluting the novel P-wave reflection approximation with seismic wavelets as the forward solver, an AVO inversion method based on the Bayesian theory is proposed to invert the TOC indicator with seismic data. The synthetic examples and field tests validate the feasibility and stability of the proposed AVO inversion approach. Using the inversion results of the TOC indicator, TOC is directly and accurately estimated in the target area.

关键词： TOC Rock physics Seismic reflectivity AVO inversion Source rocks

Regulation of Thermogenesis in Plants:The Interaction of Alternative Oxidase and Plant Uncoupling Mitochondrial Protein

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Journal of Integrative Plant Biology 2011年第1期53卷 7-13页

作者： Yan Zhu Jianfei Lu Jing Wang fu chen Feifan Leng Hongyu Li MOE Key Laboratory of Arid and Grassland Ecology School of Life Sciences Lanz-hou University Lanzhou 730000 China College of Food Science and Engineering Gansu Agriculture University Lanzhou 730070 China Institute of Potato Gansu Academy of Agricultural Sciences Lanzhou 730070 China

Thermogenesis is a process of heat production in living organisms. It is rare in plants, but it does occur in some species of angiosperm. The heat is generated via plant mitochondrial respiration. As possible involvement in thermogenesis of mitochondrial factors, alternative ox- idases （AOXs） and plant uncoupling mitochondrial proteins （PUMPs） have been well studied. AOXs and PUMPs are ubiquitously present in the inner membrane of plant mitochondria. They serve as two major energy dissipation systems that balance mitochondrial respiration and uncoupled phosphorylation by dissipating the H~ redox energy and proton electrochemical gradient （A#H~） as heat, respectively. AOXs and PUMPs exert similar physiological functions during homeothermic heat production in thermogenic plants. AOXs have five isoforms, while PUMPs have six. Both AOXs and PUMPs are encoded by small nuclear multigene families. Multiple isoforms are expressed in different tissues or *** studies have been done in the area of thermogenesis in higher plants. In this review, we focus on the involvement and regulation of AOXs and PUMPs in thermogenesis.

关键词： Thermoregulation Plants Planting Organizations Production Productivity Products Heat Heating Energy

Current status and trends in small nucleic acid drug development:Leading the future

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3802-3817页

作者： Yuxi Miao chen fu Zhaojin Yu Lifeng Yu Yu Tang Minjie Wei Department of Pharmacology School of PharmacyChina Medical UniversityShenyang 110122China Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation China Medical UniversityShenyang 110122China Liaoning Medical Diagnosis and Treatment Center Shenyang 110000China Department of Oncology Cancer Hospital of China Medical UniversityLiaoning Cancer Hospital and InstituteShenyang 110042China

Small nucleic acid drugs,composed of nucleotides,represent a novel class of pharmaceuticals that differ significantly from conventional small molecule and antibody-based *** agents function by selectively targeting specific genes or their corresponding messenger RNAs(mRNAs),further modulating gene expression and regulating translation-related *** examples within this category include antisense oligonucleotides(ASO),small interfering RNAs(siRNAs),micro-RNAs(miRNAs),and *** emergence of small nucleic acid drugs as a focal point in contemporary biopharmaceutical research is attributed to their remarkable specificity,facile design,abbreviated development cycles,expansive target spectrum,and prolonged *** challenges such as poor stability,immunogenicity,and permeability issues have been addressed through the integration of chemical modifications and the development of drug delivery *** review provides an overview of the current status and prospective trends in small nucleic acid drug *** with a historical context,we introduce the primary classifications and mechanisms of small nucleic acid ***,we delve into the advantages of the *** and Drug Administration(FDA)approved drugs and mainly discuss the challenges encountered during their *** from researching chemical modification and delivery system that efficiently deliver and enrich small nucleic acid drugs to target tissues,promoting endosomal escape is a critical scientific question and important research direction in siRNA drug *** directions in this field will prioritize addressing these challenges to facilitate the clinical transformation of small nucleic acid drugs.

关键词： Small nucleic acid drugs Oligonucleotide drugs siRNA ASO miRNA Aptamer RNAi Drug development