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Assessment of Lubrication Property and Machining Performance of Nanofluid Composite Electrostatic Spraying(NCES)Using Different Types of Vegetable Oils as Base Fluids of External Fluid
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作者 Yu Su Zepeng Chu +2 位作者 Le Gong Bin Wang Zhiqiang Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期97-110,共14页
The current study of minimum quantity lubrication(MQL)concentrates on its performance improvement.By contrast with nanofluid MQL and electrostatic atomization(EA),the proposed nanofluid composite electrostatic sprayin... The current study of minimum quantity lubrication(MQL)concentrates on its performance improvement.By contrast with nanofluid MQL and electrostatic atomization(EA),the proposed nanofluid composite electrostatic spraying(NCES)can enhance the performance of MQL more comprehensively.However,it is largely influenced by the base fluid of external fluid.In this paper,the lubrication property and machining performance of NCES with different types of vegetable oils(castor,palm,soybean,rapeseed,and LB2000 oil)as the base fluids of external fluid were compared and evaluated by friction and milling tests under different flow ratios of external and internal fluids.The spraying current and electrowetting angle were tested to analyze the influence of vegetable oil type as the base fluid of external fluid on NCES performances.The friction test results show that relative to NCES with other vegetable oils as the base fluids of external fluid,NCES with LB2000 as the base fluid of external fluid reduced the friction coefficient and wear loss by 9.4%-27.7%and 7.6%-26.5%,respectively.The milling test results display that the milling force and milling temperature for NCES with LB2000 as the base fluid of external fluid were 1.4%-13.2%and 3.6%-11.2%lower than those for NCES with other vegetable oils as the base fluids of external fluid,respectively.When LB2000/multi-walled carbon nanotube(MWCNT)water-based nanofluid was used as the external/internal fluid and the flow ratio of external and internal fluids was 2:1,NCES showed the best milling performance.This study provides theoretical and technical support for the selection of the base fluid of NCES external fluid. 展开更多
关键词 Nanofluid composite electrostatic spraying Lubrication property Machining performance Vegetable oil External fluid
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Study on Electromagnetorheological Fluid Containing CuPc-Fe_3O_4 Nanoparticles Composite 被引量:1
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作者 姜德生 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第1期35-37,共3页
Electromagnetorheological (EMR) fluids containing CuPc-Fe3O4 nanoparetictes composite were prepared and their properties were studied. The results show that AT of this kind of EMR fluids increases with the increments ... Electromagnetorheological (EMR) fluids containing CuPc-Fe3O4 nanoparetictes composite were prepared and their properties were studied. The results show that AT of this kind of EMR fluids increases with the increments of applied electric field, magnetic field and volume fraction of the nanoparticles composite. Ar has an approximate linear relationship with γ. When an electric and magnetic field are applied simultaneously, the EMR fluids have a synergistic effect. The EMR fluids have a good long-term stability. 展开更多
关键词 nanopareticles composite EMR fluid SYNERGISTIC effect
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Study on Treatment of the Pesticide Wastewater by the Composite Process of Biological Active Carbon Filter-Fluid Bed 被引量:2
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作者 YANG Tao ZHENG Wei +2 位作者 YU Hai-cheng WU Cong SONG Shan-cheng 《Meteorological and Environmental Research》 2012年第7期35-37,41,共4页
[ Objectlve] The research aimed to study treatment effect of the pesticide wastewater by the composite process of biological active car- bon filter-fluid bed. [Method] The composite process of biological active carbon... [ Objectlve] The research aimed to study treatment effect of the pesticide wastewater by the composite process of biological active car- bon filter-fluid bed. [Method] The composite process of biological active carbon filter- fluid bed was applied to treat the mixed pesticide wastewater. The removal efficiencies of CODcr, BODs, NH3-N, SS and the influence factors were investigated. [ Result] The composite process had good treatment efficiency for pesticide wastewater. After running stably, the average removal rates of CODc,, BODs, NH3-N and SS were re- spectively 91.6%, 96.2%, 90.2% and 87.5%. All indices reached the third level cdteda specified in Comprehensive Standard of the Sewage Dis- charge (DB12/356-2008). [ Conclusionl The whole system operates reliably and simply, and provides a stable, convenient and economical solu- tion for deep treatment of the mixed pesticide wastewater. 展开更多
关键词 Biological active carbon fluid bed Pesticide wastewater composite process China
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CHARACTERIZATION OF MANGANESE PHTHALOCYANINE-Fe_3O_4 NANOPARTICLE COMPOSITE AND ITS ELECTROMAGNETORHEOLOGICAL FLUID
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作者 HUANG Jun GUAN Jianguo ZHAO Suling YUAN Runzhang Wuhan University of Technology 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1999年第1期35-40,共6页
Manganese phthalocyanine (MnPc)-Fe3O4 nanoparticles composite was prepared and characterized. The results show that MnPc are completed on the surface of Fe3O4 nanoparticles in the state of single molecule. There is ef... Manganese phthalocyanine (MnPc)-Fe3O4 nanoparticles composite was prepared and characterized. The results show that MnPc are completed on the surface of Fe3O4 nanoparticles in the state of single molecule. There is effective composite between MnPc and Fe3O4 nanoparticles which can improve the antioxidization ability of Fe3O4 nanoparticles greatly. The composite was dispersed into chlorinated paraffin oil to form electromag-netorheological (EMR) fluid with high activity, and the EMR properties of this EMR fluid are studied. 展开更多
关键词 manganese phthaloc yanine nanopar- ticles composite electramagnetorheological fluid
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Free Vibration Analysis of Symmetrically Laminated Composite Plates on Elastic Foundation and Coupled with Stationary Fluid 被引量:1
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作者 Arash SHAHBAZTABAR Ahmad RAHBAR-RANJI 《China Ocean Engineering》 SCIE EI CSCD 2018年第3期266-277,共12页
Free vibration analysis of symmetrically laminated composite plates resting on Pasternak elastic support and coupled with an ideal, incompressible and inviscid fluid is the objective of the present work. The fluid dom... Free vibration analysis of symmetrically laminated composite plates resting on Pasternak elastic support and coupled with an ideal, incompressible and inviscid fluid is the objective of the present work. The fluid domain is considered to be infinite in the length direction but bounded in the depth and width directions. In order to derive the eigenvalue equation, Rayleigh-Ritz method is applied for the fluid-plate-foundation system. The efficiency of the method is proved by comparison studies with those reported in the open literature. At the end, parametric studies are carried out to examine the impact of different parameters on the natural frequencies. 展开更多
关键词 free vibration analysis laminated composite plate fluid-plate-foundation interaction Rayleigh-Ritz method Pasternak foundation
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Analysis of Dynamic Structure-Fluid Interaction Response of a Floating Laminated Composite Plate
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作者 Tang, WY Wang, DY Chen, TY 《China Ocean Engineering》 SCIE EI 1997年第4期363-372,共10页
In consideration of the effects of transverse shear deformation and structure-fluid interaction, the analytical expression of fluid force between a floating laminated composite plate and liquid surface is obtained. By... In consideration of the effects of transverse shear deformation and structure-fluid interaction, the analytical expression of fluid force between a floating laminated composite plate and liquid surface is obtained. By expanding the displacements into Fourier series, the structure-fluid coupling dynamic response is solved. The effects of lamination angle, layer number, depth of fluid region and loading forms on dynamic response are investigated. 展开更多
关键词 composite structure laminated plate structure-fluid interaction dynamic response
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Dynamic Structure-Fluid Interaction Response of a Composite Cylindrical Shell Submerged in Water
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作者 Tang, WY Zhang, SK Chen, TY 《China Ocean Engineering》 SCIE EI 1998年第3期297-307,共11页
This paper analyzes the dynamic structure-fluid interaction response of a submerged composite cylindrical shell. Dynamic equations based on the first-order shear deformation theory include the initial stresses and str... This paper analyzes the dynamic structure-fluid interaction response of a submerged composite cylindrical shell. Dynamic equations based on the first-order shear deformation theory include the initial stresses and structure-fluid interaction forces due to fluid. The field equation is solved by expanding the velocity potential into series similar to transverse deflection of the cylindrical shell and the structure-fluid interaction force is obtained. The dynamic response is investigated by means of series expansion method. The effects of structure-fluid interaction on dynamic response are discussed. 展开更多
关键词 composite structure laminated cylindrical shell structure-fluid interaction dynamic response
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Compositions of Upper Mantle Fluids Beneath Eastern China: Implications for Mantle Evolution 被引量:17
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作者 ZHANGMingjie WANGXianbin +2 位作者 LIUGang ZHANGTongwei BOWenrui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期125-130,共6页
The composition of gases trapped in olivine, orthopyroxene and clinopyroxene in Iherzolite xenoliths collected from different locations in eastern China has been measured by the vacuum stepped-heating mass spectrometr... The composition of gases trapped in olivine, orthopyroxene and clinopyroxene in Iherzolite xenoliths collected from different locations in eastern China has been measured by the vacuum stepped-heating mass spectrometry. These xenoliths are hosted in alkali basalts and considered as residues of partial melting of the upper mantle, and may contain evidence of mantle evolution. The results show that various kinds of fluid inclusions in Iherzolite xenoliths have been released at distinct times, which could be related to different stages of mantle evolution. In general, primitive fluids of the upper mantle (PFUM) beneath eastern China are dominated by H2, CO2 and CO, and are characterized by high contents of H2 and reduced gases. The compositions of PFUM are highly variable and related to tectonic settings. CO, CO2 and H2 are the main components of the PFUM beneath cratons; the PFUM in the mantle enriched in potassic metasomatism in the northern part of northeastern China has a high content of H2, while CO2 and SO2 are the dominant components of the PFUM in the Su-Lu-Wan (Jiangsu-Shandong-Anhui) region, where recycled crustal fluids were mixed with deeper mantle components. There are several fluids with distinct compositions beneath eastern China, such as primitive fluids of upper mantle (CO, CO2 and H2), partial melting fluids (CO2 and CO) and metasomatic fluids mixed with recycled crustal fluids (CO2, N2, SO2 and CH4) etc. Fluids of the upper mantle beneath the North China craton are different from that of the South China craton in total gases and chemical compositions: the contents of the reduced gases of the PFUM in the NCC are higher than those in the SCC. 展开更多
关键词 chemical composition mantle fluids Iherzolite xenoliths eastern China
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Decrepitation Thermometry and Compositions of Fluid Inclusions of the Damoqujia Gold Deposit,Jiaodong Gold Province,China:Implications for Metallogeny and Exploration 被引量:30
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作者 杨立强 邓军 +6 位作者 张静 郭春影 高帮飞 龚庆杰 王庆飞 江少卿 于海军 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期378-390,共13页
The recently discovered Damoqujia (大磨曲家) gold deposit is a large shear zone-hosted gold deposit of disseminated sulphides located in the north of the Zhaoping (招平) fault zone, Jiaodong (胶东) gold province... The recently discovered Damoqujia (大磨曲家) gold deposit is a large shear zone-hosted gold deposit of disseminated sulphides located in the north of the Zhaoping (招平) fault zone, Jiaodong (胶东) gold province, China. In order to distinguish the temperature range of cluster inclusions from different mineralization stages and measure their compositions, 16 fluid inclusions and 5 isotopic geochemistry samples were collected for this study. Corresponding to different mineralization stages, the multirange peaks of quartz decrepitation temperature (250-270, 310-360 and 380-430℃) indicate that the activity of ore-forming fluids is characterized by multistage. The ore-forming fluids were predominantly of high-temperature fluid system (HTFS) by CO2-rich, and SO4^2--K^+ type magmatic fluid during the early stage of mineralization and were subsequently affected by low-temperature fluid system (LTFS) of CH4-rich, and Cl^--Na^+/Ca^2+ type meteoric fluid during the late stage of mineralization. Gold is transferred by Au-HS^- complex in the HTFS, and Au-Cl^- complex can be more important in the LTFS. The transition of fluids from deeper to shallow environments results in mixing between the HTFS and LTFS, which might be one of the most key reasons for gold precipitation and large-scale mineralization. The ore-forming fluids are characterized by high-temperature, strong-activity, and superimposed mineralization, so that there is a great probability of forming large and rich ore deposit in the Damoqujia gold deposit. The main bodies are preserved and extend toward deeper parts, thereby suggesting a great potential in future. 展开更多
关键词 decrepitation thermometry composition of fluid inclusion Damoqujia gold deposit orogenic gold deposit intrusion-related gold system EXPLORATION
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Simulation of the plasticizing behavior of composite modified doublebase(CMDB)propellant in grooved calendar based on adaptive grid technology 被引量:2
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作者 Su-wei Wang Xiu-duo Song +6 位作者 Zong-kai Wu Lei Xiao Guang-pu Zhang Yu-bing Hu Ga-zi Hao Wei Jiang Feng-qi Zhao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第6期1954-1966,共13页
The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)propellant.Optimization of process parameters with ... The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base(CMDB)propellant.Optimization of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering process.To improve the accuracy of the simulation results,material parameters and model structure were corrected based on actual conditions,and adaptive grid technology was applied in the local mesh refinement.In addition,the rheological behavior,motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps,rotational rates and temperatures of two rollers.The results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the outlet.Compared with the gap,the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear dragging.Meanwhile,under the synergistic effect of contact heat transfer as well as convective heat exchange,heat accumulated near the outlet and diffused along the reflux movement,which led to the countercurrent heat dissipation behavior of CMDB propellant slurry.The plasticizing mechanism of slurry and the safety of calendering under different conditions were explored,which provided theoretical guidance and reference data for the optimization of calendering process conditions.Based on the simulation results,the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle. 展开更多
关键词 composite modified double base propellant Calendering process fluid simulation Vortex flow0
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Sulfur isotopic composition of the Tianqiao Pb-Zn ore deposit,Northwest Guizhou Province,China:Implications for the source of sulfur in the ore-forming fluids 被引量:17
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作者 ZHOU Jiaxi HUANG Zhilong +3 位作者 ZHOU Guofu LI Xiaobiao DING Wei BAO Guangping 《Chinese Journal Of Geochemistry》 EI CAS 2010年第3期301-306,共6页
The Tianqiao Pb-Zn ore deposit of Guizhou Province, China, is located in the mid-east of the Sichuan-Yunnan-Guizhou Pb-Zn-Ag multi-metallic mineralization area, which is representative of the Pb-Zn ore de-posits in th... The Tianqiao Pb-Zn ore deposit of Guizhou Province, China, is located in the mid-east of the Sichuan-Yunnan-Guizhou Pb-Zn-Ag multi-metallic mineralization area, which is representative of the Pb-Zn ore de-posits in this area. It consists of three main orebodies, whose Pb+Zn reserves are more than 0.2 million ton. This paper analyzes the sulfur isotopic composition of these orebodies. The data show that the ore minerals (galena, sphalerite, pyrite) in these orebodies are enriched in heavy sulfur, with δ34SV-CDT values varying between 8.35‰ and 14.44‰, i.e. the δ34SV-CDT values of pyrite are between 12.81‰ and 14.44‰, the mean value is 13.40‰; the δ34SV-CDT values of sphalerite are range from 10.87‰ to 14.00‰, the mean value is 12.53‰; the δ34SV-CDT values of galena are range from 8.35‰ to 9.83‰, the mean value is 8.84‰, and they have the feature of δ34Spyrite>δ34Ssphalerite>δ34Sgalena, which indicates the sulfur isotope in ore-forming fluids has attained equilibrium. The δ34S V-CDT values of the deposit are close to those of sulfates from carbonate strata of different ages in the ore-field (15‰), which suggests that the sulfur in the ore-forming fluids should be derived from the thermo-chemical sulfate reduction of sulfates from the sedimentary strata. 展开更多
关键词 硫同位素组成 成矿流体来源 铅锌矿 贵州省 天桥 中国 西北部 硫酸盐还原
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Sulfur isotopic composition of the Bainiuchang super-large Ag polymetallic deposit,Yunnan Province,China: Implications for the source of sulfur in ore-forming fluids 被引量:7
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作者 XIE Hongjing ZHU Chaohui +2 位作者 ZHANG Qian WANG Dapeng FAN Liangwu 《Chinese Journal Of Geochemistry》 EI CAS 2009年第3期284-292,共9页
The Bainiuchang deposit in Yunnan Province, China, is located geographically between the Gejiu ore field and the Dulong ore field. In addition to >7000 t Ag reserves, the deposit possesses large-scale Pb, Zn, Sn re... The Bainiuchang deposit in Yunnan Province, China, is located geographically between the Gejiu ore field and the Dulong ore field. In addition to >7000 t Ag reserves, the deposit possesses large-scale Pb, Zn, Sn reserves and a mass of dispersed elements (i.e., In, Cd, Ge, Ga, etc.). Based on systematic studies of sulfur isotopic composition, the authors conclude: The Bainiuchang deposit experienced two epochs of metallogenesis, i.e., the Middle-Cambrian sea-floor exhalative sedimentary metallogenic epoch and the Yanshanian magmatic hydrothermal superimposition metallogenic epoch. In the two metallogenic epochs, the δ34S values of sulfides were all near 0, showing a tendency of being enriched slightly in heavy sulfur. The δ34S values of sulfides in the early metallogenic epoch are within the range of 2‰–5‰ with a peak value range of 2‰–3‰ and an average of 3.0‰, and those of sulfides in the late metallogenic epoch are within the range of 2‰–6‰ with a peak value of 3‰–4‰ and an average of 3.9‰. For the single metallogenic epoch, sulfur in the ore-forming fluids in the early epoch already reached isotopic equilibrium and was derived mainly from underneath the magma chamber or basement metamorphic igneous rocks. Sulfur in the sulfides in the late epoch was derived mainly from magmatic hydrothermal fluids formed in the process of remelting of the basement metamorphic igneous rocks. 展开更多
关键词 硫同位素组成 银多金属矿床 成矿流体 白牛厂 云南省 中国 超大型 成矿时代
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Fluid Composition and Carbon & Oxygen Isotope Geochemistry of Cenozoic Alkali Basalts in Eastern China 被引量:3
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作者 张铭杰 刘刚 +1 位作者 文启彬 李立武 《Chinese Journal Of Geochemistry》 EI CAS 1999年第3期276-282,共7页
The fluid compositions of Cenozoic alkali basalts in eastern China have been determined by the pyrolysis MS method, meanwhile the carbon and oxygen isotopic compositions of CO 2 released from these samples at differen... The fluid compositions of Cenozoic alkali basalts in eastern China have been determined by the pyrolysis MS method, meanwhile the carbon and oxygen isotopic compositions of CO 2 released from these samples at different heating temperatures have been analyzed by the vacuum step heating method. The data show the volatile heterogeneity in upper mantle sources and different evolution trends of alkali basaltic magmas in eastern China, and these alkali basaltic magmas may be generated in the oxidizing milieu, as compared with mantle derived xenoliths in these alkali basalts, and exotic volatile components were mixed into these magmas in the process of their formation and development. 展开更多
关键词 流体成分 氧同位素 碳同位素 碱性玄武岩 华东地区 同位素地球化学 新生代
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Ordovician Seawater Composition:Evidence from Fluid Inclusions in Halite
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作者 MENG Fanwei ZHANG Yongsheng +3 位作者 Galamy A.R. XING Enyuan NI Pei JI Limin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期23-23,共1页
Fluid inclusions in halite can directly record the major composition of seawater,however Ordovician halite is very rare.Ordovician is a key time during the evolution history.However there are no Ordovician seawater da... Fluid inclusions in halite can directly record the major composition of seawater,however Ordovician halite is very rare.Ordovician is a key time during the evolution history.However there are no Ordovician seawater data reported except from the data from the halite from the 展开更多
关键词 ORDOVICIAN seawater composition fluid inclusion HALITE
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Sol-Gel Preparation of Graphite/TiO_2 Composite Particles and Their Electrorheological Effect
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作者 Ling ZHENG and Yinong LIState Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, ChinaAssoc. Prof., Ph.D., 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第1期83-86,共4页
Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRD, SEM and TG-DTA. The electrorheological properties of... Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRD, SEM and TG-DTA. The electrorheological properties of the ER fluid containing the particles were measured by a Couette-type rheometer under shear rates of 1-136 s-1 and AC electric fields of 0-3 kV/mm. The experimental results show that the leaking current density of the ER fluid is higher than that of pure titanium dioxide particles dispersed in damping oil. The shear yield stress of the ER fluid increases with increasing electric field and exhibits a typical Bingham flow behavior. The suspension demonstrates an excellent ER performance (τ/τo=1200) compared with conventional ER fluids (τ/τ0 ≤500). The sedimentation of the ER fluid is improved obviously due to the coating effect of the particles. 展开更多
关键词 Electrorheological fluid composite particle GRAPHITE TIO2 SOL-GEL
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Tourmalinization at the Darasun goldfield,Eastern Transbaikalia:Compositional,fluid inclusion and isotopic constraints
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作者 Vsevolod Prokofiev Ivan Baksheev +3 位作者 Lidiya Zorina Boris Belyatsky Vladimir Ustinov Nadezhda Krivitskaya 《Geoscience Frontiers》 SCIE CAS 2012年第1期59-71,共13页
Zoned tourmaline (schorl-dravite) in the matrix of hydrothermal explosive breccia and ore veins in gold deposits, Chita region, Eastern Transbaikalia, Russia, are associated with Na- and K-rich porphyry-type subvolc... Zoned tourmaline (schorl-dravite) in the matrix of hydrothermal explosive breccia and ore veins in gold deposits, Chita region, Eastern Transbaikalia, Russia, are associated with Na- and K-rich porphyry-type subvolcanic intrusives. 61So values of tourmaline from three gold deposits (Darasun, Talatui, Teremkinskoye) are +8.3%, +7.6%, and --6.0% and calculated 6180 values of fluids respon- sible for the tourmalinization are +7.3%, +7.7%, and +4.2%, respectively. These data imply an igneous fluid source, except at the Teremkin deposit where mixing with meteoric water is indicated. Wide ranges of Fe3+/Fetot and the presence of vacancies characterize the Darasun deposit tourmaline indicating wide ranges off(O2) and pH of mineralizing fluids. Initial stage tourmalines from the gold deposits of the Darasun ore district are dravite or high mg schorl. Second stage tourmaline is characterized by oscillatory zoning but with Fe generally increasing towards crystal rims indicating decreasing temperature. Third stage tourmaline formed unzoned crystals with XMg (mole fraction of Mg) close to that of the first stage tourmaline, due to a close association with pyrite and arsenopyrite. From Fe^3+/Fetot values, chemical composition and crystallization temperatures, logf(O2) of mineralizing fluids ranged from ca. -25 to 20, much higher than for the gold-bearing beresite-listvenite association, indicating that tourmalinization was not related to gold mineralization. 展开更多
关键词 Tourmaline composition fluid inclusions Oxygen isotopes Gold deposits TRANSBAIKALIA RUSSIA
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Effects of Dietary Energy Level and Source on Blood Metabolites,Hormone Secretion and Follicular Fluid Composition in Gilts
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作者 ZHOU Dong-sheng ZHUO Yong +3 位作者 WU De WANG Yan-zhong TAN Xian-yi ZHOU Ping 《畜牧兽医学报》 CAS CSCD 北大核心 2010年第S1期43-50,共8页
The objective of the study was to investigate the effects of dietary energy levels and sources on the blood metabolites,hormone secretion and the composition of follicular fluid in gilts.Fifty-four gilts with initial ... The objective of the study was to investigate the effects of dietary energy levels and sources on the blood metabolites,hormone secretion and the composition of follicular fluid in gilts.Fifty-four gilts with initial body weight of(59±4.2) kg were randomly allotted to six treatments.Treatments were low, normal,and high energy feeding levels,which were 87.5%,100%and 112.5%of recommendatory energy requirements by NRC(1998),respectively,and dietary energy sources(starch or fat).Blood samples and follicular fluids were collected on D18 and D19 of the second estrous cycle.The results showed that plasma concentrations of triglycerides and total cholesterol were higher in the fat group than that in the starch group(P【0.05),but those of glucose were similar between the two energy sources(P】0.05);dietary energy level exerted no effect on blood metabolites concentration(P】0.05).Gilts fed the high energy diet had a higher area under curve of plasma insulin(Insulin AUC),insulin-like growth factor-Ⅰ(IGF-Ⅰ) and leptin than did gilts fed the lower energy diet(P【0.05),but there was no significant difference between fat versus starch(P】0.05).Luteinizing hormone(LH) pulses were higher in gilts fed high energy rather than that in low energy diets(P】0.05),plasma concentration of estradiol(E<sub>2</sub>) was higher in the fat group than that in the starch group(P【0.05).The number of large follicles(diameter≥4 mm) and concentrations of IGF-Ⅰand E<sub>2</sub> in follicular fluid were increasing significant as the level of energy increased(P【0.05),but the numbers of large follicles and follicular fluid composition were not affected by the source of dietary energy(P】0.05).The results indicate that gilts fed high energy diets had elevated plasma concentrations of metabolic hormones,IGF-Ⅰand LH secretion,and increased follicular fluid concentrations of IGF-Ⅰ,E<sub>2</sub> and numbers of large follicles;gilts fed the dietary fat had a higher plasma concentration of cholesterol and E<sub>2</sub>. 展开更多
关键词 dietary energy levels and sources GILTS METABOLITES hormone secretion follicle fluid composition
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Effects of Cultivar and Maturity Stage on Chemical Composition and Ruminal Digestibility of Oat and Barley Hay Using Rumen Fluid or Faecal Liquor as the Inoculum
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作者 ZHANGYong-gen YUP CHRISTENSENDA 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期127-133,共7页
Two experiments were conducted to study the effects of variety and maturity stage on chemical composition and in vitro dry matter degradability of oat and barley forages. In exp1, four oat varieties and one barley var... Two experiments were conducted to study the effects of variety and maturity stage on chemical composition and in vitro dry matter degradability of oat and barley forages. In exp1, four oat varieties and one barley variety were harvested at three maturity stages: stage 1, Two weeks before stage 2; stage 2, Mid-dough for oat and early-dough for barley; stage 3, One week after stage 2. All samples were analyzed for DM, CP, ether extract, ash, ADF(acid detergent fiber), NDF(neutral detergent fiber), ADL(acid detergent lignin), NDICP(neutral detergent insoluble crude protein) and IVDMD(In vitro dry matter digestibility). There was no difference in chemical components and IVDMD among oat variety. But maturity stage had a profound influence on some nutrient contents and IVDMD. With maturity advancing, CP decreased from15.5% to 11.03% and from 14.7% to 10.9% at stage 1 and stage 2 for oat and for barley, respectively, and IVDMD decreased slowly from 72.0% to 64.9% and from 73.5% to 68.8% for oat and for barley, respectively. For fiber fractions, NDF declined before stage 2 and then level off after stage 2, while ADF changed little throughout maturation. The ADL trended to increase with increased maturity. The results from the present experiment revealed that Bailor has relatively greater IVDMD value and kept lower ADL content than any other cultivars. The observed variation in chemical composition and ruminal digestibility among various oat cultivars would allow breeders choose suitable oat forages for cattle diet. In experiment. 2, the DaisyⅡ incubator was used to compare IVDMD values of forages of seven oat cultivars using rumen fluid or faecal liquor as the inoculum source. There was a strong linear relationship between the two estimates (R 2 = 0.809; P < 0.001), which indicated that fecal liquor method has the potential to be used instead of rumen fluid for estimation of in vitro digestibility of forage. It is suggested the method for determination of IVDMD using faecal liquor was appropriate for batch operation with precision and efficiency. 展开更多
关键词 OAT BARLEY maturity stages chemical composition IVDMD rumen fluid fecal liquor
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Effect of Structural Parameters on the Performance of NS High-efficiency Composite TraysⅠ.The Effect of Aperture and Opening Ratio on NS High-efficiency Composite Trays 被引量:2
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作者 Qiao Yingyun Tian Yuanyu +1 位作者 Xu Jingfang Xie Kechang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第3期56-61,共6页
In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely structured packing were investigated.The effect of aperture a... In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely structured packing were investigated.The effect of aperture and opening ratio of plate on the fluid dynamics of the NS high-efficiency composite trays,such as the dry tray pressure drop,the wet tray pressure drop,the entrainment,the froth height,the leakage and mass transfer characteristics,were investigated.As a result, the low pressure drop,the high efficiency and the high capacity are the main advantages of the NS high-efficiency composite trays compared to other types of trays.According to this study,small aperture is useful for reducing the pressure drop and entrainment with a high mass transfer efficiency;while large aperture can achieve high capacity and efficiency in a broader operating range at the same pressure drop and entrainment. 展开更多
关键词 结构参数 托盘 NS 复合 光圈 性能 流体动力学 低压降
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Application of Heterogeneous Composite Model with Consideration of Stress Sensitive in Low Permeability Gas Reservoir
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作者 Muwang Wu Hao Liang 《International Journal of Geosciences》 2020年第11期756-767,共12页
Stress sensitivity is a key factor affecting the productivity of single wells in low permeability gas reservoirs. A well test model for heterogeneous composite gas reservoirs under the influence of stress-sensitive ef... Stress sensitivity is a key factor affecting the productivity of single wells in low permeability gas reservoirs. A well test model for heterogeneous composite gas reservoirs under the influence of stress-sensitive effects was established. Based on the theoretical model, the well test was designed by gradually increasing the pressure difference. The relationship between abnormal high pressure and reservoir stress sensitivity was analyzed. Theoretical research shows that stress sensitivity will cause permeability damage during the production process, and the pressure drop test curve shows that the physical properties of the reservoir have gradually deteriorated. The pressure recovery test curve shows that the physical properties of the reservoir are getting better. Field practice shows that stress sensitivity is related to the formation of abnormally high pressure in the formation without considering the micro-cracks in the formation. Stress-sensitive reservoirs are generally unbalanced and compacted due to overpressure, for fluid expansion/conduction overpressure in Ledong Area. For these reservoirs, there is almost no stress sensitivity. The research results have significance for guiding the design and data interpretation of stress-sensitive reservoir. 展开更多
关键词 Ledong Area Stress Sensitivity composite Gas Reservoir Well Test Model UNDERCOMPACTION fluid Expansion/Conduction
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