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Advances and Challenges of Exosome Metabolomics in Body Fluids
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作者 CAO Yiqing HOU Jingxin +1 位作者 LIU Jianye LI Yan 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期1-15,共15页
Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and ... Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and metabolites,although most studies have primarily focused on proteins and RNA.Recently,exosome metabolomics has demonstrated clinical value and potential advantages in disease detection and pathophysiology,despite significant challenges,particularly in exosome isolation and metabolite detection.This review discusses the significant technical challenges in exosome isolation and metabolite detection,highlighting the advancements in these areas that support the clinical application of exosome metabolomics,and illustrates the potential of exosomal metabolites from various body fluids as biomarkers for early disease diagnosis and treatment. 展开更多
关键词 EXOSOME Metabolomics Body fluid BIOMARKER Disease diagnosis
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Simulation and Experimental Analysis of Mechanical Properties of a Bidirectional Adjustable Magnetorheological Fluid Damper
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作者 YANG Zhi−rong YE Zhong−min +2 位作者 LIU Jin−liang RAO Zhu−shi XIAO Wang−qiang 《船舶力学》 北大核心 2025年第6期1000-1012,共13页
The aim of this study is to address the issues associated with traditional magnetorheological fluid(MRF)dampers,such as insufficient damping force after power failure and susceptibility to settlement.In order to achie... The aim of this study is to address the issues associated with traditional magnetorheological fluid(MRF)dampers,such as insufficient damping force after power failure and susceptibility to settlement.In order to achieve this,a bidirectional adjustable MRF damper was designed and developed.Magnetic field simulation analysis was conducted on the damper,along with simulation analysis on its dynamic characteristics.The dynamic characteristics were ultimately validated through experimental testing on the material testing machine,thereby corroborating the theoretical simulation results.Concurrently,this process generated valuable test data for subsequent implementation of the semi-active vibration control system.The simulation and test results demonstrate that the integrated permanent magnet effectively accomplishes bidirectional regulation.The magnetic induction intensity of the damping channel is 0.2 T in the absence of current,increases to 0.5 T when a maximum forward current of 4 A is applied,and becomes 0 T when a maximum reverse current of 3.8 A is applied.When the excitation amplitude is 8 mm and the frequency is 2 Hz,with the applied currents varying,the maximum damping force reaches 8 kN,while the minimum damping force measures at 511 N.Additionally,at zero current,the damping force stands at 2 kN,which aligns closely with simulation results.The present paper can serve as a valuable reference for the design and research of semi-active MRF dampers. 展开更多
关键词 magnetorheological fluid(MRF) DAMPER permanent magnet finite element analysis test of mechanical properties
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Enhanced dynamic impact resistance of UHMWPE fabrics impregnated with double-thickening shear thickening fluid
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作者 Yiting Meng Heyu Chen +3 位作者 Hengyu Lin Zhehong Lu Yubing Hu Yanan Zhang 《Defence Technology(防务技术)》 2025年第7期321-333,共13页
Inspired by the thermal stability mechanism of thermophilic protein,which presents ionic bonds that have better stability at higher temperatures,this paper proposes the introduction of electrostatic interactions by ad... Inspired by the thermal stability mechanism of thermophilic protein,which presents ionic bonds that have better stability at higher temperatures,this paper proposes the introduction of electrostatic interactions by adding carboxyl-modified silica(C-SiO2),PAA,and CaCl_(2) to achieve higher viscosity over 25℃.The rheological behavior of C-SiO_(2)-based shear thickening fluid(CS-STF)was investigated at a temperature range of 25–55℃.Unlike SiO_(2)-based STF,which exhibits single-step thickening and a negative correlation between viscosity and temperature.As the C-SiO_(2) content was 41%(w/w)and the mass ratio of PAA:CaCl_(2):C-SiO_(2) was 3:1:10,the CS-STF displayed a double-thickening behavior,and the peak viscosity reached 1330 Pa·s at 35℃.From the yarn pull-out test,the inter-yarn force was significantly increased with the increasing CS-STF content.Treating UHMWPE fabrics with CS-STF improved the impact resistance effectively.In the blunt impact test,the U-CS fabrics with high CS-STF content(121.45 wt%)experienced penetration failure under high impact energy(18 J)due to stress concentration caused by the shear thickening behavior.The knife stabbing test demonstrated that U-CS fabrics with appropriate content(88.38 wt%)have the best stabbing resistance in various impact energies.Overall,this study proposed a high-performence STF showing double-thickening and enhancing shear-thickening behavior at a wide temperature range,the composite fabrics with the performance of resisting both the blunt and stab impact had broad application prospects in the field of personal protection. 展开更多
关键词 Shear thickening fluid Double-thickening behavior UHMWPE fabrics Dynamic impact resistance
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FluidSIM和“5S”在液压传动实践教学中的应用 被引量:9
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作者 花传祥 张丽珍 陈成明 《实验室研究与探索》 CAS 北大核心 2009年第8期36-38,175,共4页
在液压传动实践教学中应用FluidSIM软件对回路进行模拟运行和检验,使学生能够清晰地了解各元件在回路各个运动阶段的工作过程,加深对元件和回路原理的理解。结合液压传动实验台,通过实操的方式参与到液压传动回路设计和仿真的整个过程,... 在液压传动实践教学中应用FluidSIM软件对回路进行模拟运行和检验,使学生能够清晰地了解各元件在回路各个运动阶段的工作过程,加深对元件和回路原理的理解。结合液压传动实验台,通过实操的方式参与到液压传动回路设计和仿真的整个过程,激发学生的学习兴趣,提高学习效果。此外,根据液压传动实验台的特点,将"5S"活动引入液压传动实践教学,培养学生自我管理、严于律己、持之以恒的基本职业素质。 展开更多
关键词 实践教学 液压传动 fluidsIM软件 “5S”管理
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FluidSIM在液压与气动控制仿真实验中的应用 被引量:10
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作者 郭联金 潘斌 《实验技术与管理》 CAS 北大核心 2015年第8期121-126,共6页
采用基于FluidSIM软件的系统仿真技术,简化了液压与气动控制系统的设计和分析。介绍了最新版FluidSIM软件的功能特点,并分别通过电液比例控制系统的建模及仿真、气动步进顺控系统的建模及仿真两个实例,说明FluidSIM在现代液压与气动控... 采用基于FluidSIM软件的系统仿真技术,简化了液压与气动控制系统的设计和分析。介绍了最新版FluidSIM软件的功能特点,并分别通过电液比例控制系统的建模及仿真、气动步进顺控系统的建模及仿真两个实例,说明FluidSIM在现代液压与气动控制新技术中的应用方法和实现过程。仿真过程及结果表明,FluidSIM的运用有助于液压与气动控制系统的分析、设计和工程应用研究。 展开更多
关键词 电液比例位置控制 气动控制系统 仿真实验 fluidsIM
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Rheological properties of oil-based drilling fluids at high temperature and high pressure 被引量:4
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作者 赵胜英 鄢捷年 +1 位作者 舒勇 张洪霞 《Journal of Central South University》 SCIE EI CAS 2008年第S1期457-461,共5页
The rheological properties of two kinds of oil-based drilling fluids with typically composition were studied at pressures up to 138 MPa and temperatures up to 204 ℃ using the RheoChan 7400 Rheometer.The experimental ... The rheological properties of two kinds of oil-based drilling fluids with typically composition were studied at pressures up to 138 MPa and temperatures up to 204 ℃ using the RheoChan 7400 Rheometer.The experimental results show that the apparent viscosity,plastic viscosity and yield point decrease with the increase of temperature,and increase with the increase of pressure.The effect of pressure on the apparent viscosity,plastic viscosity and yield point is considerable at ambient temperature.However,this effect gradually reduces with the increase of temperature.The major factor influencing the rheological properties of oil-based drilling fluids is temperature instead of pressure in the deep sections of oil wells.On the basis of numerous experiments,the model for predict the apparent viscosity,plastic viscosity and yield point of oil-based drilling fluids at high temperature and pressure was established using the method of regressive analysis.It is confirmed that the calculated data are in good agreement with the measured data,and the correlation coefficients are more than 0.98.The model is convenient for use and suitable for the application in drilling operations. 展开更多
关键词 OIL-BASED DRILLING fluids HIGH temperature HIGH pressure RHEOLOGICAL property MATHEMATICAL model
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MANTLE SOURCE NATURE OF ORE FLUIDS FOR THE JINDING Pb-Zn DEPOSIT, LANPING, YUNNAN 被引量:2
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作者 Zhang Lisheng, Yu Qian, Mou Chuanlong 《地学前缘》 EI CAS CSCD 2000年第S1期419-420,共2页
Geological setting\;Jinding superlarge Pb\|Zn deposit lies in the Lanping basin between the Lancangjiang fracture zone and the Jinshajiang\|Ailaoshan fracture zone. The Lanping basin is a Meso\|Cenozoic rifting basin ... Geological setting\;Jinding superlarge Pb\|Zn deposit lies in the Lanping basin between the Lancangjiang fracture zone and the Jinshajiang\|Ailaoshan fracture zone. The Lanping basin is a Meso\|Cenozoic rifting basin whose basement consists of the Paleozoic strata. Mesozoic paralic and continental sediments with a thickness of about 20000m deposited in the basin. In the Paleocene, gypsum\|salt\|bearing strata with a thickness of more than 1000m accumulated. In the Cenozoic, collision of the Indian plate with the Eurasian plate resulted in strong folding and napping and subsequent extensions in the Oligocene and Pliocene. The extensions were responsible for alkaline magmatic intrusion in the centre and alkaline magmatic extrusion in the east.Faulting is well developed. N\|S\|trending Bijiang fault with a length of 120km links with the Jinshajiang fracture zone in the north and with the Lancangjiang fracture zone in the south, controlling on the Cenozoic Lanping rifting basin and acting as passage\|way for ore fluids. 展开更多
关键词 JINDING Pb\|Zn DEPOSIT MANTLE source ORE fluid
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EVOLUTION OF ORE-FORMING FLUIDS AND Ag-Cu POLYMETAL MINERALIZATION IN THE LANPING BASIN, YUNNAN 被引量:1
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作者 Wang C. S., Tang J. X., Gu X. X. 《地学前缘》 EI CAS CSCD 2000年第S1期409-409,共1页
The Lanping Mesozoic—Cenozoic sedimentary basin, situated in the Middle section of the “Sanjiang" (Nujiang—Lancangjiang—Jinshajiang) area in the east margin of the Tibet plateau, is well known for its large p... The Lanping Mesozoic—Cenozoic sedimentary basin, situated in the Middle section of the “Sanjiang" (Nujiang—Lancangjiang—Jinshajiang) area in the east margin of the Tibet plateau, is well known for its large production of base\|metal sulphide deposits. The worldwide famous super\|large Jinding Pb\|Zn deposit is located in the middle of the basin. The evolution history of the Lanping basin since Mesozoic can be divided into six stages, i.e., ①active continental marginal basin (T 1—T 2); ②back\|arc rift basin (T 3—J 1); ③intracontinental depressive basin (J 2—J 3); ④foreland basin (K); ⑤strike\|slipping and mutual thrusting (E 1—E 3); and ⑥strike\|slipping and pull\|apart basin (N 1\|present). Three main types of Ag\|Cu polymetal deposits are recognized in the basin. Deposits of sedimentary exhalation\|hydrothermal reworking origin (type Ⅰ) are hosted chiefly in limestones, dolomitic limestones, and siliceous rocks of the Upper Triassic Sanhedong Formation (T 3 s ) in Sanshan area. Deposits formed through normal chemical sedimentation in closed to semi\|closed environments (type Ⅱ; e.g., Jinman and Baiyangchang) during the depressive and foreland basin stages occur in various horizons of Jurassic and Cretaceous ages. Hydrothermal reworking on deposits of this type during the Himalayan period are locally pronounced, especially in the west margin of the basin near the Lancangjiang thrust fault. The third deposit type in the basin (type Ⅲ; e.g., Baiyangping and Fulongchang) is the Ag\|bearing tetrahedrite vein deposits occurring almost in all Mesozoic—Cenozoic strata, especially in the Cretaceous. Ore minerals formed during synsedimentary periods of types Ⅰ and Ⅱ are relatively simple and dominated by chalcopyrite and bornite, though sphalerite, galena, pyrite, tetrahedrite and pyrite are also present. In the deposits of type Ⅲ as well as in the ores formed during the hydrothermal reworking period in deposits of type Ⅰ and Ⅱ, ore minerals are extremely complicated and characterized by predominant Ag\|bearing tetrahedrite and other complex sulfosalts of Cu\|Ni\|Co\|Fe\|As\|S and Cu\|Bi\|S series. The associated gangue minerals are mainly quartz, siderite, Fe\|dolomite, barite, and celestite. 展开更多
关键词 BASIN fluids polymetal MINERALIZATION BASIN evolut ion Lanping BASIN
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Estimation of the Patients'Adaptation to Noble Alloy Dentures Relying on the Parameters of Biological Fluids in Oral Cavities 被引量:1
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作者 LEBEDENKO I.Yu. PARUNOV V.A. KITKINA T.B. 《贵金属》 CAS CSCD 北大核心 2012年第A01期246-249,共4页
For the study of the effect of Plagodent and Palladent noble alloy dentures (OJSC "SIC 'Supermetal'", Russia), the elemental compositions of the fluids obtained from gingival sulcus of abutment teeth... For the study of the effect of Plagodent and Palladent noble alloy dentures (OJSC "SIC 'Supermetal'", Russia), the elemental compositions of the fluids obtained from gingival sulcus of abutment teeth of metal ceramic dentures with frames made of the above-stated dental alloys, have been investigated. Response of white blood cells and fibroblasts in the gingival fluid and the mixed saliva of the patients a long time after prosthetic repair, relying on the content of proinflammatory interleukins IL-1 β and IL-6, anti-inflammatory interleukins IL-4 and IL-10, the factor of tumor necrosis TNF-α and lactoferrin, has been investigated. The results obtained have convincingly proved the biosafety of the Plagodent and Palladent noble alloys. 展开更多
关键词 noble dental alloys BIOCOMPATIBILITY gingival fluid INTERLEUKINS LACTOFERRIN
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Numerical simulation of single bubble rising in shear-thinning fluids by level set method 被引量:4
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作者 李少白 烟征 +2 位作者 李润东 王雷 栾敬德 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期1000-1006,共7页
The behavior of single bubble rising in quiescent shear-thinning tlmds was lnvestlgateO numerically by level set metnoa. number of bubbles in a large range of Reynolds number and Eotvos number were investigated includ... The behavior of single bubble rising in quiescent shear-thinning tlmds was lnvestlgateO numerically by level set metnoa. number of bubbles in a large range of Reynolds number and Eotvos number were investigated including spherical, oblate and spherical. The bubble shape and drag coefficient were compared with experimental results. It is observed that the simulated results show good conformity to experimental results over a wide range of Reynolds number. In addition, the detailed flow field based on the reference coordinate system moving with the bubble is obtained, and the relationship among flow field, bubble shape and velocity is discussed. 展开更多
关键词 single bubble shear thinning fluid numerical simulation level set method
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Rheological property of low-damage,ideal packing,film-forming amphoteric/sulfonation polymer drilling fluids 被引量:2
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作者 张洪霞 鄢捷年 +1 位作者 舒勇 赵胜英 《Journal of Central South University》 SCIE EI CAS 2008年第S1期429-433,共5页
Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pr... Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations. 展开更多
关键词 low-permeability dense gas condense reservoir AMPHION and SULFONATION polymer drilling fluid DAMAGE controlling water-blocking ideal packing theory(IPT) film-forming agent rheological properties
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Effect of different heat transfer fluids on discharging performance of phase change material included cylindrical container during forced convection 被引量:2
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作者 SELİMEFENDİGİL Fatih ŞİRİN Ceylin ÖZTOP Hakan F 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3521-3533,共13页
In the present work,effects of various heat transfer fluids on the discharging performance of a phase change material(PCM) included cylindrical container are numerically assessed during forced convection.The heat tran... In the present work,effects of various heat transfer fluids on the discharging performance of a phase change material(PCM) included cylindrical container are numerically assessed during forced convection.The heat transfer fluid air,hydrogen,water and nanofluid with alumina particles are used and the the geometric variation of the PCM embedded region is also considered.The finite element method is used as the solver.Dynamic features of heat exchange with various phases are explored for different heat transfer fluid types,Reynolds number(between 100 and 300) and PCM embedded region geometric variation(h_(x)between 0.01 d_(1) and 0.65 d_(1),hybetween 0.1 h_(1) and 0.4 h_(1)).It is observed that discharging time is significantly influenced by the heat transfer fluid type while full phase transition time for air is obtained as more than 10 times when hydrogen is utilized as heat transfer fluid.The best performance is achieved with nanofluid.When the PCM integrated region size is reduced,discharging time is generally reduced while due to the form of the geometry,vortex formation is established in the PCM region.This results in performance degeneration at the highest radius and height of the inner cylinder.Discharging time increases by about 12% when radius of the inner cylinder is increased from h_(x)=0.35 d_(1) to h_(x)=0.45 d_(1).Dynamic features of PCM temperature and liquid fraction are affected with Reynolds number while discharging time is reduced by about 48% when configurations with the lowest and highest Reynolds number are compared. 展开更多
关键词 heat transfer fluid HYDROGEN phase change material finite element method container shape
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Effect of surfactants on hydrodynamics characteristics of bubble in shear thinning fluids at low Reynolds number 被引量:1
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作者 LI Shao-bai FAN Jun-geng +2 位作者 LI Run-dong WANG Lei LUAN Jing-de 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期805-811,共7页
In this study,the effects of surfactants on the hydrodynamic characteristics of bubbles in shear-thinning fluids at low Reynolds number(Re<50)are investigated.The bubble terminal velocity and drag coefficient of bu... In this study,the effects of surfactants on the hydrodynamic characteristics of bubbles in shear-thinning fluids at low Reynolds number(Re<50)are investigated.The bubble terminal velocity and drag coefficient of bubble in clean and contaminated carboxymethylcellulose(CMC)solutions are obtained using a high-speed camera for examining differences.The results show that the existence of surfactant could reduce the terminal velocity of bubble at small volume(0.25wt%CMC:<100 mm3;0.50wt%CMC:<110 mm3),attributed to stiffening the bubble interface.However,this negative effect decreases and finally disappears with increasing bubble volume.The drag coefficient curves of the bubble in contaminated CMC solution exhibit behavior similar to that exhibited by a solid sphere at Re<10,indicating that internal circulation flow is absent at the bubble interface as compared to that in clean CMC solution.However,for 10<Re<40,a transition of drag curve from 24/Re to 16/Re in contaminated CMC solution is observed,which is easy at low SDS concentrations and high CMC concentrations. 展开更多
关键词 SURFACTANT single bubble shear thinning fluids VELOCITY drag coefficient
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Evaluation of working fluids for organic Rankine cycles using group-contribution methods and second-law-based models 被引量:1
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作者 MA Wei-wu WANG Lin +1 位作者 LIU Tao LI Min 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2234-2243,共10页
The group-contribution (GC) methods suffer from a limitation concerning to the prediction of process-related indexes, e.g., thermal efficiency. Recently developed analytical models for thermal efficiency of organic Ra... The group-contribution (GC) methods suffer from a limitation concerning to the prediction of process-related indexes, e.g., thermal efficiency. Recently developed analytical models for thermal efficiency of organic Rankine cycles (ORCs) provide a possibility of overcoming the limitation of the GC methods because these models formulate thermal efficiency as functions of key thermal properties. Using these analytical relations together with GC methods, more than 60 organic fluids are screened for medium-low temperature ORCs. The results indicate that the GC methods can estimate thermal properties with acceptable accuracy (mean relative errors are 4.45%-11.50%);the precision, however, is low because the relative errors can vary from less than 0.1% to 45.0%. By contrast, the GC-based estimation of thermal efficiency has better accuracy and precision. The relative errors in thermal efficiency have an arithmetic mean of about 2.9% and fall within the range of 0-24.0%. These findings suggest that the analytical equations provide not only a direct way of estimating thermal efficiency but an accurate and precise approach to evaluating working fluids and guiding computer-aided molecular design of new fluids for ORCs using GC methods. 展开更多
关键词 organic Rankine cycles (ORCs) group contribution methods working fluids property estimation computer-aided molecular design
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Notes on the Gaseous Phase of Mineral Forming Fluids of Metamorphic Rocks of Berlebash Suite of Marmarosh Massif of the Ukrainian Carpathians(by Fluid Inclusions)
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作者 Roman A.Bondar 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期219-219,共1页
Marmarosh massif is an important structural element of the Eastern Carpathians,which differs by the geological features from the other structural-facial zones of Carpathian fold belt.Metamorphic rocks of the massif ha... Marmarosh massif is an important structural element of the Eastern Carpathians,which differs by the geological features from the other structural-facial zones of Carpathian fold belt.Metamorphic rocks of the massif have been formed under the influence of the processes of medium-and low-temperature meta-morphism and metasomatism.Within the Marmarosh massif the stratiform gold ore has 展开更多
关键词 fluid inclusions METAMORPHIC rocks Marmarosh MASSIF
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Constraints of REE and trace elements of high-pressure-veins and host rocks in western Tianshan on origin of deep fluids in paleosubduction zones 被引量:1
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作者 黄德志 高俊 戴塔根 《Journal of Central South University of Technology》 2005年第2期192-198,共7页
The western Tianshan high-pressure(HP) metamorphic belt represents the paleosubduction mélange of paleozoic south Tianshan ocean between the Yili-central Tianshan and Tarim plates. High-pressure veins are extensi... The western Tianshan high-pressure(HP) metamorphic belt represents the paleosubduction mélange of paleozoic south Tianshan ocean between the Yili-central Tianshan and Tarim plates. High-pressure veins are extensively developed in this HP belt. Compared with normal mid-ocean ridge basalt(N-MORB), the high-pressure veins and host rocks are enriched in light rare earth elements(LREE) and incompatible elements. But high-pressure veins show a larger variation than host rocks in total REE abundance. On the trace element spidergram, all the samples are enriched in incompatible elements and show strong positive Pb anomaly relative to N-MORB. The array tendency lines of plots of the HP rocks have apparent slopes on diagram of m(Sr) vs m(Sr)/m(Zr), m(Li) vs m(Li)/m(Y) and (m(Ce)) vs m(Ce)/m(Pb), which indicates that the enrichment in LREE and incompatible elements relative to N-MORB of the HP-metamorphic rocks from western Tianshan is not attributed to magma evolution process of the protolith. High field strength elements, such as Nb, Ta, Ti, Zr and Hf, do not show negative anomaly relative to N-MORB, which is dissimilar to that of island arc basalts. Therefore, the enrichment in LREE and incompatible elements of the HP rocks is not attributed to the enrichment of the source of the protolith. The mass ratios of Rb to Ba, Ce to Pb, Nb to U and Ta to U of high-pressure veins and host rocks are intermediate of mid-ocean ridge basalt or oceanic island basalt and continental crust. The fluids in western Tianshan paleosubduction zones are mixtures of two sources, dehydration or devolatilization of host rocks and of subducted sediments. 展开更多
关键词 rare earth elements trace element fluid in paleosubduction zone high-pressure vein host rock western Tianshan
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On energy boundary layer equations in power law non-Newtonian fluids
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作者 郑连存 张欣欣 《Journal of Central South University》 SCIE EI CAS 2008年第S1期5-8,共4页
The hear transfer mechanism and the constitutive models for energy boundary layer in power law fluids were investigated.Two energy transfer constitutive equations models were proposed based on the assumption of simila... The hear transfer mechanism and the constitutive models for energy boundary layer in power law fluids were investigated.Two energy transfer constitutive equations models were proposed based on the assumption of similarity of velocity field momentum diffusion and temperature field heat transfer.The governing systems of partial different equations were transformed into ordinary differential equations respectively by using the similarity transformation group.One model was assumed that Prandtl number is a constant,and the other model was assumed that viscosity diffusion is analogous to thermal diffusion.The solutions were presented analytically and numerically by using the Runge-Kutta formulas and shooting technique and the associated transfer characteristics were discussed. 展开更多
关键词 power LAW fluids heat TRANSFER SIMILARITY solution nonlinear BOUNDARY VALUE problem
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Challenging multiphase complex fluids for applications
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作者 许元泽 《Journal of Central South University》 SCIE EI CAS 2008年第S1期130-134,共5页
Modern processing technology is calling the scientific understanding of dynamic processes,where the science of complex fluids plays a central role.We summarize our recent efforts using the generic approaches of multi-... Modern processing technology is calling the scientific understanding of dynamic processes,where the science of complex fluids plays a central role.We summarize our recent efforts using the generic approaches of multi-scale physics of complex fluids on apparently irrelevant processes,i.e.the mixing of polymer blends,the processing of thermoplastic(TP) toughened thermosetting(TS) composites using phase separation of TP in TS,as well as the enhanced oil recovery using polymer soft gel.It is emphasized that the thorough physical understanding in multi-scales of time and space through the joint efforts of experiment and theory in each scale is the key issue for the modeling of various processes. 展开更多
关键词 complex fluid MULTI-SCALE physics polymer BLEND phase separation THERMOSETTING composite soft GEL EOR
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THE LUBRICATING MECHANISMS OF LUBRICATINGDRILLING FLUIDS ON SYNTHETIC DIAMOND BIT
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作者 Long Wei(Department of Geology, Central South University of Technology,Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第1期87-89,共3页
The functions of lubricants in diamond drilling were discussedin this paper. The influences of lubricant on drilling efficiency and bit′s life were compared and analyzed with simulated drilling test and lubrication t... The functions of lubricants in diamond drilling were discussedin this paper. The influences of lubricant on drilling efficiency and bit′s life were compared and analyzed with simulated drilling test and lubrication test apparatus. Lubricating mechanisms were also discussed. 展开更多
关键词 lubricating DRILLING fluids DIAMOND BIT DRILLING pressure〖WT5BZ
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SERPENTINIZATION OF THE MANTLE WEDGE BY FLUIDS DERIVED FROM CONTINENTAL CRUSTAL MATERIAL: EVIDENCE FROM Nd ISOTOPIC SIGNATURES OF SERPENTINITES (TSO MORARI DOME,ELADAKH)
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作者 Julia de Sigoyer 1, Thomas Ngler\+2, Stéphane Guillot\+3, Kéi ko H. Hattori\+4 2 Isotopengeologie, Universitt Bern, Erlachstrasse 9a, 3012 Bern, Switzerland 3 CNRS, Universi 《地学前缘》 EI CAS CSCD 2000年第S1期122-123,共2页
The well preserved eclogitic rocks of the Tso Morari dome in eastern Ladakh, northwest Himalaya, provide information relevant to the exhumation of high pressure/low temperature rocks, and the early stage of the Himala... The well preserved eclogitic rocks of the Tso Morari dome in eastern Ladakh, northwest Himalaya, provide information relevant to the exhumation of high pressure/low temperature rocks, and the early stage of the Himalayan orogeny. The Tso Morari unit outcrops south of the Indus suture zone (Fig.1). The eclogitic dome is underlined on its eastern part by the Zildat normal fault where serpentinite lenses and partially hydrated peridotites are abundant. The close association of the high pressure rocks and serpentinites suggests a possible role of serpentinites in the exhumation of ultrahigh\|pressure rocks. To evaluate this possibility, geochemical analyses were carried out on the serpentinites closely associated with the Tso Morari eclogites. 展开更多
关键词 EXHUMATION of eclogitic rocks SERPENTINITES REE Nd\|isot opes crustal fluid contamination mantle wedge Eastern LADAKH Himalaya
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