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Science China Technological Sciences 2024年第12期67卷 3659-3672页

作者： HU HaoYu YANG Xu CAO Feng yin xiang SONG YuLong School of Energy and Power Engineering Xi'an Jiaotong University

Transcritical CO2refrigeration cycle systems hold significant promise for improving the energy efficiency of air conditioning system in vehicles, diminishing reliance on traditional energy sources, and reducing environmental impact. Utilizing a scroll compressor-expander unit（SCEU） to recover energy during the expansion process enables the effective conversion of expansion work into useful work, thereby enhancing the efficiency of the entire refrigeration cycle. This paper provides a detailed description of the geometric structure of the SCEU, and based on this, conducts an exhaustive mechanical analysis of its orbiting scrolls and main shaft, thus establishing dynamic models. Computational results indicate that in transcritical CO2refrigeration systems, the SCEU aids in recovering expansion work, increasing the coefficient of performance（COP） by 8.2% under standard operating condition. Additionally, this paper pioneers in studying the dynamic characteristics of SCEU under variable *** is found that although the COP of the systems decreases with the rise of working pressure, compared to traditional systems, its rate of improvement progressively increases. Under conditions of negligible leakage and an isentropic efficiency of 60%, the SCEU can potentially increase the COP of the system by up to 9.8%.

关键词： transcritical CO2 refrigeration cycle systems air conditioning system in vehicles scroll compressor-expander unit dynamic models

Impact of the thermal effect on the load-carrying capacity of a slipper pair for an aviation axial-piston pump

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Chinese Journal of Aeronautics 2018年第2期31卷 395-409页

作者： Hesheng TANG Yaobao yin Yan REN Jiawei xiang Jun CHEN School of Mechanical Engineering WenZhou University School of Mechanical Engineering Tongji University Sany Heavy Industry Co. Ltd

A thermal hydraulic model based on the lumped parameter method is presented to analyze the load-carrying capacity of a slipper pair in an aviation axial-piston pump under specified operating conditions. Both theoretical and experimental results are presented to demonstrate the validity of the thermal hydraulic model. The results illustrate that the squeezing force and thermal wedge bearing force are the main factors that affect the film thickness and load-carrying *** high oil temperature and high load pressure, the film thickness decreases with increasing clamping force due to a combined action of the squeezing bearing force and the thermal wedge bearing force, but the load-carrying capacity will increase. An increase of the film thickness is proven to be beneficial under high shaft rotational speed but especially dangerous as it strongly increases the ripple amplitude of the film thickness, which leads to decreasing the load-carrying capacity. The structural parameters of the slipper can be optimized to achieve desired performance, such as the slipper radius ratio and orifice length diameter ratio. To satisfy the requirement of the load-carrying capacity, the slipper radius ratio should be selected from 1.4 to 1.8, and the orifice length diameter ratio should be selected from 4 to 5.

关键词： Aviation axial piston pumpFluid lubrication Load-carrying capacity Slipper pair Thermal effect

Flat-end tool orientation based on rotation-minimizing frame

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Advances in Manufacturing 2019年第3期7卷 257-269页

作者： xiang Zou Hon-Yuen Tam Hai-yin Xu Ke Shi School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074People's Republic of China College of Science and Engineering Department of Mechanical EngineeringCity University of Hong KongHong KongPeople's Republic of China

Well-designed tool orientation is crucial for the quality execution of five-axis machining with flat-end *** orientation can be specified in terms of tool inclination and tool tilt *** a given surface path,these aspects need to be specified for each cutter contact point along the path,because poor tool orientation choice can cause large axial acceleration of the machine tool,leading to inferior quality of the machined *** rotation-minimizing frame aims to reduce unnecessary frame rotation during *** concept has been adopted to develop tool orientation methods that allow variation in the inclination angle,the tilt angle,and both the inclination and tilt *** intention is to reduce unnecessary rotation of the tool frame as the tool follows a specified *** was conducted in the context of five-axis flat-end tool *** on these methods,tool orientation was planned along surface paths of a torus,sphere,and *** in tool orientation were always *** the perspective of reducing tool orientation changes and axial acceleration,it was demonstrated that simultaneous variation of the inclination and tilt angles based on rotation minimization provided the best results.

关键词： Five-axis machining Tool orientation Rotation-minimizing frame Numerical control

Identification of the Flavone in the Flower Bud of Panax Quinquefolium and Its Content Determination in the Different Parts

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Chemical Research in Chinese Universities 2001年第1期17卷 121-126页

作者： MENG xiang-ying LI xiang-gao TIAN Yi-xin LIU yin-yan ZHENG Lian-xiu College of Chinese Medical Material Jilin Agricultural UniversityChangchun 130118P.R.China The School of Basic Medical Sciences Norman Bethune University of Medical SciencesChangchun 130021P.R.China People Hospital of Jilin Province Changchun 130021P.R.China

Chemical constituents namely flavonoids in the flower buds of Panax quinque folium were identified and their content was determined in different parts. The content determination was performed using dual wavelength TLC-scan and ultraviolet absorption. Content determination results showed that the content of flavonoid in the flower bud was higher than in the roots.

关键词： Panax quinquefulium Flower buds Flavonoid Root Fruit

Dynamic Alignment of D2 Enhanced by Two Few-cycle Pulses

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Chinese Journal of Chemical Physics 2008年第5期21卷 421-426页

作者： Zeng-qiang Yang Zhi-rong Guo Bao-xiang yin Mao-zhu Sun Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Shihezi832003 China

Dynamic alignment of D2 induced by two few-cycle pulses was investigated by solving the time-dependent Schr6dinger equation numerically based on a rigid rotor model. The results show that alignment of D2 can be enhanced by two few-cycle pulses compared with the level achievable by a single few-cycle pulse as long as the time delay between two pulses is chosen properly, and the pulse duration of two lasers plays an important role in the aligning process of D2 molecules.

关键词： Dynamic alignment Few-cycle pulses Pulse duration

Electrochemically recycling degraded superalloy and valorizing CO_(2)in the aff ordable borate-modified molten electrolyte

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Tungsten 2024年第2期6卷 382-393页

作者： xiang Chen Yuan Sun Long Wang Xin Qu Yan Zhao hong-Wei Xie Di-Hua Wang Hua-Yi yin Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education School of MetallurgyNortheastern UniversityShenyang 110819China Institute of Metal Research Chinese Academy of ScienceShenyang 110016China School of Resource and Environmental Science Wuhan UniversityWuhan 430072China

Integrating electrochemical reduction of CO_(2)and electrochemical oxidation to recycle degraded superalloys is a promising solution to ease resource scarcity and safeguard environmental ***,we propose an electrochemical technique for the conversion of bulk superalloy scraps and CO_(2)into oxide powder at the anode and solid carbon at the cathode,*** particular,a borax-modifi ed CaCl_(2)-based molten salt electrolyte is used for enhancing the electrochemical oxidation of superalloy *** a temperature of 700℃and a voltage of 2.8 V,90.55 wt.%of alloy scraps were oxidized in a molten CaCl_(2)–NaCl–CaCO_(3)–Na_(2)B_(4)O_(7)with an acid–base ratio(K_(a/b))of *** synergy of Cl−and B_(4)O_(7)2−of electrolyte prevents the passivation of the alloy anode and enables continuous ***,the Ni and Co in the anode products are recovered by sulfation roasting with recovery efficiencies of 85.58%and 95.27%for Ni and Co,***,modulating the alkalinity of the electrolyte for enhancing oxidation/pulverization of alloy scrap anode provides new insight into electrochemically recovering superalloy scraps.

关键词： Superalloy scraps Recycling Molten salt Alkalinity Electrochemical oxidation Cobalt

The non-canonical poly(A)polymerase FAM46C promotes erythropoiesis

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Journal of Genetics and Genomics 2024年第6期51卷 594-607页

作者： Ke Yang Tiangi Zhu Jiaying yin Qiaoli Zhangg Jing Li hong Fan Gajing Han Weiyin Xu Nan Liu xiang Lv Bone Marrow Transplantation Center The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310003China Liangzhu Laboratory Zhejang UniversityHangzhouZhejang 311121China Institute of Hematology Zhejiang UniversityHangzhouZhejiang 311121China The State Key Laboratory for Complex Severeand Rare DiseasesHaihe Laboratory of Cell EcosystemDepartment of PathophysiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China Medical Epigenetics Research Center Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China

The post-transcriptional regulation of mRNA is a crucial component of gene *** disruption of this process has detrimental effects on the normal development and gives rise to various *** for novel post-transcriptional regulators and exploring their roles are essential for understanding development and *** a multimodal analysis of red blood cell trait genome-wide association studies(GWAS)and transcriptomes of erythropoiesis,we identify FAM46C,a non-canonical RNA poly(A)polymerase,as a necessary factor for proper red blood cell ***46C is highly expressed in the late stages of the erythroid lineage,and its developmental upregulation is controlled by an erythroidspecific *** demonstrate that FAM46C stabilizes mRNA and regulates erythroid differentiation in a polymerase activity-dependent ***,we identify transcripts of lysosome and mitochondria components as highly confident in vivo targets of FAM46C,which aligns with the need of maturing red blood cells for substantial clearance of organelles and maintenance of cellular redox *** conclusion,our study unveils a unique role of FAM46C in positively regulating lysosome and mitochondria components,thereby promoting erythropoiesis.

关键词： FAM46C TENT5C Poly(A)polymerase Erythroblasts Post-transcriptional regulation Erythroid-specific enhancer

Agglomeration and leaching behaviors of copper oxides with different chemical binders

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International Journal of Minerals,Metallurgy and Materials 2021年第7期28卷 1127-1134页

作者： Sheng-hua yin Lei-ming Wang Xun Chen Ai-xiang Wu Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Materials Engineering University of British Columbia309-6350 Stores RoadVancouverBC V6T 1Z4Canada

The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching *** this study,we in-vestigated the effect of the type of binder and mass fraction of the H_(2)SO_(4)solution used on the curing,soaking,and leaching behavior of *** results revealed that Portland cement(3CaO·SiO_(2),2CaO·SiO_(2),and 3CaO·Al_(2)O_(3))was the optimal binder for obtaining a well-shaped,stable agglomeration structure.A higher extraction rate was achieved when using Portland cement than that obtained using sodi-um silicate,gypsum,or acid-proof *** excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable *** computed tomography(CT)and MATLAB,the porosity of two-dimensional CT images in sample concentrations L1-L3 was observed to increase at least 4.5vol%after acid *** agglomerations began to be heavily destroyed and even to disinteg-rate when the sulfuric acid solution concentration was higher than 30 g/L,which was caused by the excessive accumulation of reaction products and residuals.

关键词： agglomeration binder acid leaching copper oxide sulfuric acid solution

Experimental Study of Preferential Solute Transportation During Dump Leaching

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Journal of China University of Mining and Technology 2006年第4期16卷 416-420页

作者： yin Sheng-hua WU Ai-xiang Key Laboratory of Educational Ministry for High Efficient Mining and Safety in Mental Mine University of Science and Technology Beijing Beijing 100083 China

The production of dump leaching of the Dexing Copper Mine was affected by a preferential solution flow. Formative mechanism of the preferential solution flow was investigated by analyzing the relationship between both dump permeability and surface tension and ore diameter. The preferential solution flow occured in the fine ore area when the application rate was low. The preferential solution flow entered into the coarse ore area because the negative pore water pressure disappeared with an increase of the application rate. The preferential solute transportation experiment was conducted by selecting NaCl as mineral. Results of the experiment showed that the concentration of the outflow solution reduced over time. The concentration of the coarse ore area outflow solution was greater than that of the fine ore area. The process of NaCl leaching can be divided into two stages. NaCl was carried out directly by diffusion--convection during the first stage, so the leaching rate increased sharply. But in the second stage, only a small amount of NaCl dissolved in the immobile water. The leaching rate increased slowly because NaC1, dissolved in the immobile water, can only be leached by diffusion.

关键词： dump leaching preferential solution flow solute preferential transportation application rate leaching rate

Computational Studies of Toluene, Methyl Ethyl Ketone, Lubricating and Their Blends: a Combination of Density Functional Theory and Molecular Dynamics

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1251-1265页

作者： XIN Yi-Shuang yin Feng-xiang Beijing University of Chemical Technology Beijing100029China Yanshan Branch of Beijing Research Institute ofChemical Industry SinopecBeijing102500China National Engineering Research Center for Synthesis of NovelRubber and Plastic Materials Beijing102500China

The microstructure and intermolecular interaction of toluene(TOL), methyl ethyl ketone(MEK), lube oil, TOL-MEK solvents, and TOL-MEK-oil solutions were studied by molecular simulation. Some simulation results agree well with the experiment, which suggests that the simulation method we adopted is a powerful tool to obtain microscopic property of the systems. The density functional theory(DFT) calculation results suggest that the interaction group of toluene and MEK is the methyl group of theirs. And the interaction between toluene and MEK is attractive. The contribution of van der Waals interaction to the change of total energy of the TOL-MEK system is major, and the second is electrostatic interaction. Molecular dynamics(MD) simulation analyzes the solubility parameter(SP), mean square displacement(MSD), radius of gyration(RG), and radial distribution function(RDF) of solvents and solutions. The results are that the solubility parameter of the blend solvents decreases with temperature, and increases with the proportion of methyl ethyl ketone in principle, and that of lube oil also trends to decrease with temperature. The MSD results give one reason of why the transmission rate of MEK is greater in membrane separation process of recovery toluene and MEK and the permeation flux increases with MEK:TOL. The RG analysis predicts that the permeability of the oil molecule is likely to rise with temperature during dewaxing solvent recovery process by membrane. The analysis of RDFs shows that the intermolecular interaction of C···C, O···O and C···O makes a major contribution to the total interaction energy.

关键词： solvent dewaxing molecular simulation density functional theory molecular dynamics