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Journal of Iron and Steel Research International 2021年第1期28卷 10-18页

作者： Li-li Wang Yu-zhu Zhang Yue long College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina

Molten slag is broken up by supersonic air into droplets through the air quenching dry slag granulation *** breakup process of blast furnace slag directly determines the droplet diameter and the waste heat *** order to gain deep insight into the granulation mechanism and visualize the breakup process,three-dimensional unsteady numerical simulation based on the k-x based shear stress transport turbulence model was conducted to simulate the transient breakup process of molten slag(k is the turbulent kinetic energy,and x is the specific dissipation rate).The coupled level-set and volume-of-fluid method was utilized to capture the sharp air–liquid *** results show that a flat film is formed firstly under the effects of air impingement,recirculation zone and pressure ***,the axial wave and the spanwise wave appear simultaneously and the film is broken up into ligaments owing to the generation of vortex and hole structure at the intersection of axial trough and spanwise ***,the ligaments are broken up into droplets owing to Rayleigh–Taylor instability at the air–liquid *** droplets smaller than 3.00 mm account for 80%,with the average diameter of 1.95 mm.

关键词： Breakup process Granulation mechanism Molten slag Air quenching Computational fluid dynamics

From molecular basics to agronomic benefits:Insights into noncoding RNA-mediated gene regulation in plants

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Journal of Integrative Plant Biology 2022年第12期64卷 2290-2308页

作者： Yuqiu Wang xing Wang Deng Danmeng zhu State Key Laboratory of Protein and Plant Gene Research School of Advanced Agricultural Sciences and School of Life SciencesPeking-Tsinghua Center for Lfe SciencesPeking UniversityBeiing 100871China Shandong Laboratory of Advanced Agricultural Sciences in Weifang Peking University Institute of Advanced Agricultural SciencesWeifang 261325China

The development of plants is largely dependent on their growth *** better adapt to a particular habitat,plants have evolved various subtle regulatory mechanisms for altering gene *** RNAs(ncRNAs)constitute a major portion of the transcriptomes of *** ncRNAs have been recognized as important regulators of the expression of genes involved in essential biological processes throughout the whole life cycles of *** this review,we summarize the current understanding of the biogenesis and contributions of small nucleolar RNA(snoRNA)-and regulatory long noncoding RNA(lncRNA)-mediated gene regulation in plant development and environmental *** regulatory ncRNAs appear to be associated with increased yield,quality and disease resistance of various species and *** ncRNAs may potentially be used as genetic resources for improving agronomic traits and for molecular *** challenges in understanding plant ncRNA biology and the possibilities to make better use of these valuable gene resources in the future are discussed in this review.

关键词： gene expression long noncoding RNA snoRNA

Prevalence of Cannabis Use around the World:A Systematic Review and Meta-Analysis,2000-2024

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China CDC weekly 2024年第25期6卷 597-604,I0013,I0014页

作者： Qianning Wang Zhen Qin xing xing He zhu Zhongwei Jia National Institute of Health Data Science Center for Drug Abuse Prevention and ControlPeking UniversityBeijingChina School of Public Health Peking UniversityBeijingChina

This study aims to perform a systematic review and meta-analysis on the global prevalence of cannabis use to inform drug prevention strategies,policy-making,and resource *** study initially screened 177,843 studies published between January 1,2000,and January 15,2024,using peer-reviewed databases including Web of Science,PubMed,Scopus,Embase,and Cochrane ***,595 studies were identified for data extraction,and 39 of these were selected as country-representative *** among the selected studies was assessed using the chi-squared test and I2 statistic,while sensitivity analysis was conducted to evaluate the robustness of the *** prevalence of cannabis use varied between 0.42%and 43.90%across 33 European countries,1.40%to 38.12%across 15 North and South American countries,0.30%to 19.10%across 16 Asian countries,and 1.30%to 48.70%across 18 Oceania and African *** pooled prevalence of cannabis use was 12.0%[95%confidence interval(CI):10.0,14.3]in countries where cannabis is legalized,compared to 5.4%(95%CI:4.3,6.9)in non-legalized *** findings indicate that the prevalence of cannabis use has disproportionately increased in most countries with the implementation of medical or recreational cannabis legalization policies and relevant geographic *** efforts are needed to monitor newly cannabis-legalized countries and prevent initial use.

关键词： prevention legal initially

Bioaccumulation of cadmium bound to humic acid by the bivalve Meretrix meretirx Linnaeus from solute and particulate pathways

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Journal of Environmental Sciences 2010年第2期22卷 198-203页

作者： xing Wu Yongfeng Jia Huijie zhu He Wang Key Laboratory of Pollution Ecology and Environmental Engineering lnstimte of Applied Ecology Chinese Academy of Sciences Shengyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Humic acid is an important pool of heavy metals in sediments. Generally, the presence of refractory humic matter in aquatic systems would decrease the bioavailability of Cd and hence control the bioaccumulation of Cd in benthic animals. In the present work, we applied a suspending system to determine the relative importance of particulate and dissolved fractions of humic acid as Cd sources for the bivalve Meretrix meretrix and to investigate the difference of bioaccumulation characteristics of Cd adsorbed on different fractions of humic acid. The results showed *** bioaccumulation characteristics of Cd from particulate and dissolved fractions of humic acid were apparently different due to biological responses of the clam to the particulates. At Cd concentration of 140 mg/kg, the accumulation of Cd from Cd associated with humic acid mixtures was mainly attributed to the dissolved fractions of humic acid. Compared to particulate fractions, Cd associated with the dissolved fractions of humic acid may be more bioavailable.

关键词： humic acid bioaccumulation cadmium Meretrix meretrix Linnaeus

Diversity in seed oil content and fatty acid composition in Acer species with potential as sources of nervonic acid

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Plant Diversity 2021年第1期43卷 86-92页

作者： xing He De-zhu Li Bo Tian Key Laboratory of Sustainable Utilization of Tropical Plant Resources Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences88 Xuefu RoadKunmingYunnan650223China Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunmingYunnan650201China Center of Economic Botany Core Botanical GardensChinese Academy of SciencesMenglunMenglaYunnan666303China University of Chinese Academy of Sciences Beijing100049China

Nervonic acid(NA,cis-15-tetracosenoic acid)is a very long-chain monounsaturated fatty acid that has been shown to be a core component of nerve fibers and nerve *** can be used to treat and prevent many neurological *** present,commercially available NA is mainly derived from Acer truncatum seeds,which contain about 5%e6%NA in their seed *** aim of this study were to identify and analyze NA-containing Acer species that could be used as NA resource *** this purpose,46 Acer species seeds were collected in China and in some or all of the seed oils from these species 15 fatty acids were detected,including linoleic acid,oleic acid(C18:1D9,C18:1D11),erucic acid,palmitic acid,NA,linolenic acid(C18:3D6,9,12,C18:3D9,12,15),eicosenoic acid(C20:1D11,C20:1D13),stearic acid,behenic acid,tetracosanoic acid,arachidic acid,and docosadienoic *** acid was detected in all samples,but the content was highly variable among *** content over 9%was detected in eleven species,of which Acer elegantulum had the highest levels(13.90%).The seed oil content,seed weight,and fatty acid profiles varied among species,but the comprehensive evaluation value(W)showed that *** could be a new potential NA resources *** results also showed that NA was significantly negatively correlated with palmitic acid,oleic acid,and eicosenoic acid,but positively correlated with eicosadienoic acid,behenic acid,erucic acid,and tetracosanoic acid,which indicate the probable pathway for NA biosynthesis in Acer *** study has identified Acer species that may serve as NA resources and will help guide subsequent species breeding programs.

关键词： Acer Nervonic acid Fatty acid Seed oil Seed weight

System-level simulation of microbolometer and read-out integrated circuit

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Science China(Technological Sciences) 2015年第5期58卷 907-915页

作者： CHEN Chao JIANG YaDong ZHANG long ZHOU Yun ZHENG xing School of Optoelectronic Information University of Electronic Science and Technology of China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

A method for system-level simulation between microbolometer designing and Read-Out Integrated Circuit(ROIC) was studied. Three-dimensional(3D) structure modeling of the microbolometer was built. Thermal capacity, thermal conductivity and resistance of the model were obtained from thermoelectric coupling Finite Element Method(FEM) based on the model. An electrical equipment circuit of microbolometer which contains these three parameters was established. By using Verilog-AMS language, the electrical equipment circuit was described as a reduced-order macro-model. Then, the reduced-order macromodel was compiled in cadence to form IP unit of microbolometer, which could be used and identified in cadence. Systemlevel simulation between microbolometer and ROIC was accomplished. Key performances of the device, including input and output characteristics, were obtained in simulation and verified by experimental results.

关键词： verified pixel Verilog histogram NETD accomplished Figure capacitance captured designing

First principle study on the possibilities of magnetism in one-dimensional In and Tl atomic wires with the full-potential linearized augmented plane wave method

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 117-122页

作者： Zhili zhu Jinhua GU Yu JIA xing HU School of Physical Engineering and Material Physics Laboratory Zheng Zhou University Zhengzhou 450052 China

Using ab initio total energy calculations with the full-potential linearized augmented plane wave method, the possibilities of magnetism in one-dimensional In and Tl wires were explored and their properties as the function of geometric structures were studied. The results suggest that the linear In and Tl wires show magnetization at the equilibrium bond distance with magnetic moments of 0.71 and 0.67 μB/atom, respectively. Allowing ions to relax, the wires were deformed as zigzag structures, but no dimerization occurs. The zigzag wires also exhibit spontaneous magnetization, although the magnetic moments are lower than those of straight wires.

关键词： Magnetism Atomic wire First-principle-study

Underlying principle of efficient propulsion in flexible plunging foils

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Acta Mechanica Sinica 2014年第6期30卷 839-845页

作者： Xiao-Jue zhu Guo-Wei He xing Zhang LNM Institute of MechanicsChinese Academy of Sciences

Passive flexibility was found to enhance propulsive efficiency in swimming *** this study,we numerically investigate the roles of structural resonance and hydrodynamic wake resonance in optimizing efficiency of a flexible plunging *** results indicates that（1）optimal efficiency is not necessarily achieved when the driving frequency matches the structural eigenfrequency;（2）optimal efficiency always occurs when the driving frequency matches the wake resonant frequency of the time averaged velocity ***,the underlying principle of efficient propulsion in flexible plunging foil is the hydrodynamic wake resonance,rather than the structural *** addition,we also found that whether the efficiency can be optimized at the structural resonant point depends on the strength of the leading edge vortex relative to that of the trailing edge *** result of this work provides new insights into the role of passive flexibility in flapping-based propulsion.

关键词： Flexibility Propulsive efficiency Structural resonance Hydrodynamic wake resonance

Effect of tube-electrode inner diameter on electrochemical discharge machining of nickel-based superalloy

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Chinese Journal of Aeronautics 2016年第4期29卷 1103-1110页

作者： Zhang Yan Xu Zhengyang xing Jun zhu Di College of Mechanical and Electrical Engineering Nanjing University of Aeronautics & Astronautics

Nickel-based superalloys are widely employed in modern aircraft engines because of their excellent material characteristics, particularly in the fabrication of film cooling holes. However, the high machining requirement of a large number of film cooling holes can be extremely challenging. The hybrid machining technique of tube electrode high-speed electrochemical discharge drilling (TEHECDD) has been considered as a promising method for the production of film cooling holes. Compared with any single machining process, this hybrid technique requires the removal of more complex machining by-products, including debris produced in the electrical discharge machining process and hydroxide and bubbles generated in the electrochemical machining process. These by-products significantly affect the machining efficiency and surface quality of the machined products. In this study, tube electrodes in different inner diameters are designed and fabricated, and the effects of inner diameter on the machining efficiency and surface quality of TEHECDD are investigated. The results show that larger inner diameters could effectively improve the flushing condition and facilitate the removal of machining by-products. Therefore, higher material removal efficiency, surface quality, and electrode wear rate could be achieved by increasing the inner diameter of the tube electrode. (C) 2015 The Authors. Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics.

关键词： Electrical discharge machining Electrochemical machining Film-cooling hole Inner diameter Nickel-based superalloys Tube electrode

Influence of characteristics of stabilized zirconia electrolyte on performance of cermet supported tubular SOFCs

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Rare Metals 2006年第Z1期25卷 273-279页

作者： LI Changjiu LI Chengxin xing Yazhe XIE Yingxin long Huiguo State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi''an Jiaotong UniversityXi''an 710049China

Ni-Al_(2)O_(3)cermet supported tubular SOFC was fabricated by thermal ***-sprayed Al_(2)O_(3)-Ni cermet coating plays dual roles of a support tube and an anode current collector.4.5mol.%yttria-stabilized zirconia(YSZ)and 10mol.%scandia-stabilized zirconia(ScSZ)coatings were deposited by atmospheric plasma spraying(APS)as the electrolyte in present *** electrical conductivity of electrolyte was measured using DC *** post treatment was employed using nitrate solution infiltration to densify APS electrolyte layer for improvement of gas *** electrical conductivity of electrolyte and the performance of single cell were investigated to optimize SOFC *** electrical conductivity of the as-sprayed YSZ and ScSZ coating is about 0.03 and 0.07 S·cm^(-1)at 1000℃,*** ohmic polarization significantly influences the performance of *** maximum output power density at 1000℃increases from 0.47 to 0.76 W·cm^(-2)as the YSZ electrolyte thickness reduces from 100μm to 40μ*** APS ScSZ coating of about 40μm as the electrolyte,the test cell presents a maximum power output density of over 0.89 W·cm^(-2)at 1000℃.

关键词： solid oxide fuel cells(SOFCs) plasma spraying yttria-stabilized zirconia(YSZ) scandia-stabilized zirconia(ScSZ) coating