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Liquid marbles containing petroleum and their properties 被引量:3
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作者 Edward Bormashenko Roman Pogreb +3 位作者 Revital Balter Hadas Aharoni Doron Aurbach Vladimir Strelnikov 《Petroleum Science》 SCIE CAS CSCD 2015年第2期340-344,共5页
Liquid marbles (non-stick droplets) containing crude petroleum are reported. Liquid marbles were ob- tained by use of fluorinated decyl polyhedral oligomeric silsequioxane (FD-POSS) powder. Marbles containing crud... Liquid marbles (non-stick droplets) containing crude petroleum are reported. Liquid marbles were ob- tained by use of fluorinated decyl polyhedral oligomeric silsequioxane (FD-POSS) powder. Marbles containing crude petroleum remained stable on a broad diversity of solid and liquid supports. The effective surface tension of marbles filled with petroleum was established. The mechanism of friction of the marbles is discussed. Actuation of liquid marbles containing crude petroleum with an electric field is presented. 展开更多
关键词 Liquid marbles Crude petroleum FrictionLow energy oil transportation effective surface tension -Electrical actuation
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ROLE OF METASOMATIC PROCESSES IN RUBY-BEARING MARBLES FORMATION OF THE SOUTHERN URAL MOUNTAINS
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作者 A.KISSIN A.TOMILINA V.KOMASHCHENKO 《地学前缘》 EI CAS CSCD 北大核心 2017年第3期257-262,共6页
Ruby-bearing marbles of the Southern Ural Mountains are developed in the metamorphic perimeter of granites-gneisses domes where high grade metamorphic granitization and diaphthoresis have occurred.Geological research ... Ruby-bearing marbles of the Southern Ural Mountains are developed in the metamorphic perimeter of granites-gneisses domes where high grade metamorphic granitization and diaphthoresis have occurred.Geological research into the development and occurrence of ruby-bearing marbles indicate that they formed as a result of repeated transformation.Their substrate consisted of an organogenous marine limestone containing Visean faunal remains.Intensive Mg metasomatism of limestone during early progressive stages of metamorphism resulted in a substrate of dolomite composition containing faunal remains with a calcite composition.Increased temperature and pressure resulted in metamorphism of early Mg metasomatites,turning them into fine-grained marble containing Visean faunal remains.Tensional stresses near the intrusive domes resulted in dedolomitization of early Mg metasomatites,giving rise to light,coarse-grained calcite marbles having polygonal-grained structure.Such carbonaceous marbles became metamorphosed around the perimeter of granite-gneiss massifs.Their rheological properties allowed for plastic flow in these marbles into areas of tectonic neutrality,forming bodies of rheomorphic marbles,sometimes even among marbled limestone.Relict bodies of Mg metasomatites underwent boudinage and rotation.Flow cleavage occurred in axial blocks of inter-dome structures and in their steep walls.Therefore platy jointing(banding,pseudo-lamination)formed in the marbles.Thickness of the plates is from several millimeters to 2-3m.Calcite underwent recrystallization with extension of grain size in the central parts of plates,sometimes amounting to 15-25cm in cross-section.Ruby-bearing marbles consist of Mg-calcite.The rock is coarse-grained,with a panidiomorphic texture.Schistosity is often observed in the plane of cleavage.Mg-calcite marble occurs among and grades into background calcite marbles,which are controlled by cleavage of flowing.It is supposed that the ruby-bearing Mg-calcite marbles bodies are elongated in the direction of dip.Their formation is caused by recrystallization under the action of rising metamorphogenic fluids at high temperatures and higher pressures(amphibolitic and epidote-amphibolitic facies).Ruby-bearing marbles formed at the end of the prograde stage of metamorphism.The early retrograde stage of metamorphism is defined by a new wave of Mg metasomatism and formation of calcite-dolomitic marbles with a poikiloblastic texture from calcite or Mg-calcite marbles.Usually the boundaries of the bodies are clear,planar,and controlled by cleavage.Studies of small bodies have shown that they are elongated in the direction of dip.Usually they contain pink corundum and/or pink spinel;red corundum is replaced by red spinel.Thus the initial marine limestones were transformed into various marbles and completely lost their primary composition and bedding as a result of metamorphism,deformation,and metasomatic transformation.Ruby-spinel mineralization in marbles is controlled by cleavage. 展开更多
关键词 Ural GEMS RUBY marbles METASOMATISM
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Zoned Zircon from Eclogite Lenses in Marbles from the Dabie-Sulu UHP Terrane,China: A Clear Record of Ultra-deep Subduction and Fast Exhumation 被引量:18
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作者 LIU Fulai A. GERDES +2 位作者 P. T. ROBINSON XUE Huaimin YE Jianguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期204-225,共22页
Eclogite lenses in marbles from the Dabie-Sulu ultrahigh-pressure (UHP) terrane are deeply subducted meta-sedimentary rocks. Zircons in these rocks have been used to constrain the ages of prograde and UHP metamorphi... Eclogite lenses in marbles from the Dabie-Sulu ultrahigh-pressure (UHP) terrane are deeply subducted meta-sedimentary rocks. Zircons in these rocks have been used to constrain the ages of prograde and UHP metamorphism during subduction, and later retrograde metamorphism during exhumation. Inherited (detrital) and metamorphic zircons were distinguished on the basis of transmitted light microscopy, cathodoluminescence (CL) imaging, trace element contents and mineral inclusions. The distribution of mineral inclusions combined with CL imaging of the metamorphic zircon make it possible to relate zircon zones (domains) to different metamorphic stages. Domain 1 consists of rounded, oblong and spindly cores with dark-luminescent images, and contains quartz eclogite facies mineral inclusion assemblages, indicating formation under high-pressure (HP) metamorphic conditions of T = 571-668℃ and P =1.7-2.02 GPa. Domain 2 always surrounds domain 1 or occurs as rounded and spindly cores with white-luminescent images. It contains coesite eclogite facies mineral inclusion assemblages, indicating formation under UHP metamorphic conditions of T = 782-849℃ and P 〉 5.5 GPa. Domain 3, with gray-luminescent images, always surrounds domain 2 and occurs as the outermost zircon rim. It is characterized by low-pressure mineral inclusion assemblages, which are related to regional amphibolite facies retrograde metamorphism of T = 600- 710℃ and P = 0.7-1.2 GPa. The three metamorphic zircon domains have distinct ages; sample H1 from the Dabie terrane yielded SHRIMP ages of 245 ± 4 Ma for domain 1, 235 ± 3 Ma for domain 2 and 215± 6 Ma for domain 3, whereas sample H2 from the Sulu terrane yielded similar ages of 244 ± 4 Ma, 233 ± 4 Ma and 214 ± 5 Ma for Domains 1, 2 and 3, respectively. The mean ages of these zones suggest that subduction to UHP depths took place over 10-11 Ma and exhumation of the rocks occurred over a period of 19-20 Ma. Thus, subduction from - 55 km to 〉 160 km deep mantle depth took place at rates of approximately 9.5-10.5 km/Ma and exhumation from depths 〉160 km to the base of the crust at -30 km occurred at approximately 6.5 km/Ma. We propose a model for these rocks involving deep subduction of continental margin lithosphere followed by ultrafast exhumation driven by buoyancy forces after break-off of the UHP slab deep within the mantle. 展开更多
关键词 zoned zircon SHRIMP U-Pb dating ultra-deep subduction fast exhumation eclogite lenses in marble Dabie-Sulu UHP belt
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Determination of F,S(total),and Cl in the Calcite Rich Limestone and Marbles by WD-XRF Spectrometry 被引量:1
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作者 Svetlana Ivanovna Shtel’makh 《Journal of Geological Resource and Engineering》 2020年第5期137-144,共8页
Determining the contents of F,S(total),and Cl in the studied samples of the limestone and marbles with high calcite contents was carried out by the nondestructive method of WDXRFS(Wavelength Dispersive X-ray Fluoresce... Determining the contents of F,S(total),and Cl in the studied samples of the limestone and marbles with high calcite contents was carried out by the nondestructive method of WDXRFS(Wavelength Dispersive X-ray Fluorescence Spectrometry).All measurements were performed in a vacuum condition using a WDXRF spectrometer S8 TIGER(Bruker AXS,Germany).The studied samples have wide ranges of F,S(total),and Cl contents,and high concentration of calcite(89.5%-99%).Main objective of this research is to develop WDXRF(WD X-ray fluorescence)technique for the determination of F,S(total),and Cl.The calculated values of the ILD(instrumental limit of the detection)were within the interval from 3 for S(total)to 37 for F mg/kg.The repeatability was found to be satisfactory with the relative standard deviations lower than 7%. 展开更多
关键词 X-ray fluorescence analysis carbonate rocks with high calcite contents LIMESTONE MARBLE analytical figures of merit
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Gamma Radiation Measurements in Tunisian Marbles
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作者 Kais Manai Chiraz Ferchichi +1 位作者 Mansour Oueslati Adel Trabelsi 《World Journal of Nuclear Science and Technology》 2012年第3期80-84,共5页
The radioactivity of 15 kinds of different granites collected in Tunisia was determined by gamma-ray spectrometry using hyper-pure germanium (HPGe) detector. The average activity concentrations for primordial radionuc... The radioactivity of 15 kinds of different granites collected in Tunisia was determined by gamma-ray spectrometry using hyper-pure germanium (HPGe) detector. The average activity concentrations for primordial radionuclides 238U, 232Th and 40K were respectively 33.24, 8.01 and 116.98 Bq/kg. The activity concentrations ranged from 3.59 to 87.37 Bq/kg for 238U, from 0.45 to 25.34 Bq/kg for 232Th and from 24.06 to 380.23 Bq/kg for 40K. The measured activity concentrations were used to assess of the radium equivalent activity ranged from 22.2 to 995.8 Bq/kg, the absorbed dose rate in air from 7 to 1209 nGy/h and the internal (0.1 to 2.8) and external (0.1 to 2.7) hazard indices. The data obtained in this study may be useful for natural radioactivity mapping. 展开更多
关键词 RADIOACTIVITY MARBLE RADIUM EQUIVALENT External and Internal HAZARD Indices
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The Marbles
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作者 卢爱龙 《初中生必读》 2019年第1期68-70,共3页
It was during the Great Depression(2) in a small village. Food and money were still in very short supply and trading goods for other goods was very common.Mr. Miller sold some fresh produce on the roadside. I used to ... It was during the Great Depression(2) in a small village. Food and money were still in very short supply and trading goods for other goods was very common.Mr. Miller sold some fresh produce on the roadside. I used to trade things with him.One day when I paid for my potatoes. 展开更多
关键词 marbles MONEY POTATOES
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Oxygen and carbon isotope composition from the UHP Shuanghe marbles, Dabie Mountains, China 被引量:10
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作者 王清晨 Douglas Rumble 《Science China Earth Sciences》 SCIE EI CAS 1999年第1期88-96,共9页
Investigations on the oxygen and carbon isotope compositions from the ultrahigh-pressure (UHP)-metamorphosed Shuanghe marbles, that occur as a member of a UHP slab, show that the δ18 O values range from +11.1% to+20.... Investigations on the oxygen and carbon isotope compositions from the ultrahigh-pressure (UHP)-metamorphosed Shuanghe marbles, that occur as a member of a UHP slab, show that the δ18 O values range from +11.1% to+20.5% SMOW, and δ13 C from+1.0% to+5.7% PDB, respectively. The variations in isotope compositions show a centimeter scale of homogeneity and a heterogeneity of regional scale larger than 1 meter.In contrast to the eclogite marbles from Norway, the Shuanghe marbles have inherited the carbon isotope compositions from their sedimentary precursor. The δ13C shows positive correlation to the content of dolomite. The depletion in18O, compared with the pmtolithic carbonate strata, might result from three possible geological processes: 1) exchanging oxygen isotope with meteoric water before the UHP metamorphism, 2) decarbonation during the UHP metamorphism, and 3) exchanging oxygen isotope with country gneiss at local scale during retrograde metamorphism.It seems that the advection of fluid in the orogenic belt was very limited during subduction and exhumation of UHP rocks. 展开更多
关键词 oxygen and carbon ISOTOPE UHP METAMORPHISM Shuanghe MARBLE DABIE Mountains of China.
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Gas marbles: ultra-long-lasting and ultra-robust bubbles formed by particle stabilization
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作者 Xuxin Zhao Kunling Yang +2 位作者 Zhou Liu Ho Cheung Shum Tiantian Kong 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2022年第11期1681-1687,共7页
Bubbles and foams are ubiquitous in daily life and industrial processes.Studying their dynamic behaviors is of key importance for foam manufacturing processes in food packaging,cosmetics and pharmaceuticals.Bare bubbl... Bubbles and foams are ubiquitous in daily life and industrial processes.Studying their dynamic behaviors is of key importance for foam manufacturing processes in food packaging,cosmetics and pharmaceuticals.Bare bubbles are inherently fragile and transient;enhancing their robustness and shelf lives is an ongoing challenge.Their rupture can be attributed to liquid evaporation,thin film drainage and the nuclei of environmental dust.Inspired by particle-stabilized interfaces in Pickering emulsions,armored bubbles and liquid marble,bubbles are protected by an enclosed particle-entrapping liquid thin film,and the resultant soft object is termed gas marble.The gas marble exhibits mechanical strength orders of magnitude higher than that of soap bubbles when subjected to overpressure and underpressure,owing to the compact particle monolayer straddling the surface liquid film.By using a water-absorbent glycerol solution,the resulting gas marble can persist for 465 d in normal atmospheric settings.This particle-stabilizing approach not only has practical implications for foam manufacturing processes but also can inspire the new design and fabrication of functional biomaterials and biomedicines. 展开更多
关键词 BUBBLE particles interfaces armored bubble liquid marble gas marble Pickering emulsion
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Fabrication of cellulose based superhydrophobic microspheres for the production of magnetically actuatable smart liquid marbles
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作者 Xinxing Lin Wei Ma +3 位作者 Hui Wu Liulian Huang Lihui Chen Atsushi Takahara 《Journal of Bioresources and Bioproducts》 EI 2017年第3期110-115,共6页
Cellulose microspheres were fabricated on the basis of sol-gel transition using NaOH/urea/H_(2)O as the solvent system.These microspheres had an average diameter of about 30μm.Upon modification with Fe_(3)O_(4) and p... Cellulose microspheres were fabricated on the basis of sol-gel transition using NaOH/urea/H_(2)O as the solvent system.These microspheres had an average diameter of about 30μm.Upon modification with Fe_(3)O_(4) and poly(DOPAm-co-PFOEA),superhydrophobic magnetic cellulose microspheres were generated,which were analyzed by FTIR,TG,XRD,XPS and water contact angle tests.Magnetic cellulose microspheres contained approximately 15 wt%of Fe_(3)O_(4).Poly(DOPAm-co-PFOEA)/Fe_(3)O_(4)/cellulose microspheres and had a low surface energy and a high water-repellency.These superhydrophobic microspheres were also converted into liquid marbles via an easily scalable process. 展开更多
关键词 Superhydrophobic microspheres Magnetically actuatable Smart liquid marble Cellulose microsphere
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Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains 被引量:3
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作者 Yongfei Zheng Bin Fu +2 位作者 Bing Gong Yilin Xiao Yiliang Li 《Chinese Science Bulletin》 SCIE EI CAS 1998年第2期155-160,共6页
This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results place constraints on the degree of crust_mantle interaction during the UHP metamorphism.
关键词 carbon isotopes marble and ECLOGITE UHP METAMORPHISM crust_mantle interaction DABIE Mountains.
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Mechanical response and dilatancy characteristics of deep marble under different stress paths:A sight from energy dissipation
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作者 LIU Xiao-hui HAO Qi-jun +2 位作者 ZHENG Yu ZHANG Zhao-peng XUE Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2070-2086,共17页
Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses ... Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses on Jinping marble obtained from the Jinping Underground Laboratory in China at a depth of 2400 m.Various uniaxial and triaxial tests at different strain rates,along with constant confining pressure tests and reduced confining pressure tests under different confining pressures were conducted to analyze the mechanical response and dilatancy characteristics of the marble under four stress paths.Subsequently,a new empirical dilatancy coefficient is proposed based on the energy dissipation method.The results show that brittle failure characteristics of marble under uniaxial compression are more obvious with the strain rate increasing,and plastic failure characteristics of marble under triaxial compression are gradually strengthened.Furthermore,compared to the constant confining pressure,the volume expansion is relatively lower under unloading condition.The energy dissipation is closely linked to the process of dilatancy,with a rapid increase of dissipated energy coinciding with the beginning of dilatancy.A new empirical dilatancy coefficient is defined according to the change trend of energy dissipation rate curve,of which change trend is consistent with the actual dilatancy response in marble under different stress paths.The existing empirical and theoretical dilatancy models are analyzed,which shows that the empirical dilatancy coefficient based on the energy background is more universal. 展开更多
关键词 deep marble stress paths DILATANCY energy dissipation empirical dilatancy coefficient
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Marbling计算机仿真技术综述 被引量:3
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作者 卢书芳 金小刚 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2014年第2期179-190,共12页
Marbling是一门在液体表面制作彩色流体状图案的传统手工艺术,Marbling的计算机仿真技术是现今计算机图形学领域中模拟传统绘画方法的一大组成部分.文中对现有的计算机Marbling仿真技术进行了全面的综述,并对它们在模拟方法、模拟对象... Marbling是一门在液体表面制作彩色流体状图案的传统手工艺术,Marbling的计算机仿真技术是现今计算机图形学领域中模拟传统绘画方法的一大组成部分.文中对现有的计算机Marbling仿真技术进行了全面的综述,并对它们在模拟方法、模拟对象、实现平台和输出格式等方面进行了详细介绍、分析和对比讨论;将现有仿真方法分为基于物理的模型方法和基于数学的模型方法2类,并介绍了3种不同类型的Marbling纹理图案的模拟技术.最后对全文进行总结,讨论了该领域未来的发展趋势和研究方向. 展开更多
关键词 Marbling纹理 流体模拟 数学模型 计算机艺术 水影画
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基于marble的三维可视化技术研究 被引量:1
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作者 程延锋 王俊江 +1 位作者 曹红艳 王艳侠 《微型机与应用》 2016年第9期18-19,23,共3页
随着三维可视化技术的高速发展和广泛应用,很多应用工程领域需要三维地理信息系统显示空间数据。据此介绍了marble的特点和应用方式,详细论述使用VS2008和Qt构建marble源码的基本过程。应用实例表明,基于marble的空间数据三维图形显示... 随着三维可视化技术的高速发展和广泛应用,很多应用工程领域需要三维地理信息系统显示空间数据。据此介绍了marble的特点和应用方式,详细论述使用VS2008和Qt构建marble源码的基本过程。应用实例表明,基于marble的空间数据三维图形显示真实、形象、直观。 展开更多
关键词 三维可视化 MARBLE QT VS2008
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基于marble的等值线显示研究
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作者 程延锋 郭延波 +2 位作者 杨东升 张连迎 陈跃 《计算机科学与技术汇刊(中英文版)》 2016年第1期9-13,共5页
随着三维可视化技术的高速发展和广泛应用,很多应用工程领域需要三维地理信息系统显示等值线.据此本文介绍了在marble上高效实现等值线.实例结果表明,基于marble的等值线显示真实、形象和直观.
关键词 等值线 MARBLE 地域网格 QT
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互动大理石
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作者 韩佳成 Daan Roosegaard 《设计》 2012年第3期63-63,共1页
MARBLES是一件互动性极强的公共装置,“大理石”都采用互动科技,通过声音和光线色彩的变化来反映参观者的接近或是触碰。并且还能通过彼此的状态相互影响和交流。
关键词 大理石 石材加工 marbles 互动性
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气-固两相旋转射流场稳定性研究
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作者 周泽宣 林建忠 《杭州应用工程技术学院学报》 1999年第4期1-7,共7页
采用考虑悬浮固粒与气流相互作用的Marble压力耦合模型和涉及悬浮固粒容积系数与平均固粒雷诺数的修正斯托克斯阻力公式,得到了含悬浮固粒的旋转射流稳定性控制方程及相应的修正瑞利稳定性准则.通过计算,给出了不同团粒属性及气相跳... 采用考虑悬浮固粒与气流相互作用的Marble压力耦合模型和涉及悬浮固粒容积系数与平均固粒雷诺数的修正斯托克斯阻力公式,得到了含悬浮固粒的旋转射流稳定性控制方程及相应的修正瑞利稳定性准则.通过计算,给出了不同团粒属性及气相跳跃速度下旋转射流的增长率和发展系数曲线,根据所得稳定性准则,得到了固粒属性对旋转射流稳定性影响的重要结论,文中结论为工程控制旋转射流场及后续发展提供了理论依据. 展开更多
关键词 气-固两相旋转射流场 稳定性 Marble压力耦合模型 修正斯托克斯阻力公式 固粒属性
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Strainburst process of marble in tunnel-excavation-induced stress path considering intermediate principal stress 被引量:24
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作者 JIANG Bang-you GU Shi-tan +2 位作者 WANG Lian-guo ZHANG Guang-chao LI Wen-shuai 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第4期984-999,共16页
Strainburst is one type of rockburst that generally occurs in deep tunnel.In this study,the strainburst behaviors of marble specimens were investigated under tunnel-excavation-induced stress condition,and two stress p... Strainburst is one type of rockburst that generally occurs in deep tunnel.In this study,the strainburst behaviors of marble specimens were investigated under tunnel-excavation-induced stress condition,and two stress paths were designed,a commonly used stress path in true triaxial unloading rockburst tests and a new test path in which the intermediate principal stress was varied.During the tests,a high-speed camera was used to record the strainburst process,and an acoustic emission(AE)monitoring system was used to monitor the AE characteristics of failure.In these two stress paths,all the marble specimens exhibited strainbursts;however,when the intermediate principal stress was varied,the rockburst became more violent.The obtained results indicate that the intermediate principal stress has a significant effect on rockburst behavior of marble.Under a higher intermediate principal stress before the unloading,more elastic strain energy was accumulated in the specimen,and the cumulative AE energy was higher in the rockburst-induced failure,i.e.,more elastic strain energy was released during the failure.Therefore,more violent failure was observed:more rock fragments with a higher mass and larger size were ejected outward. 展开更多
关键词 strainburst true triaxial test intermediate principal stress acoustic emission MARBLE
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Vitamin A administration at birth promotes calf growth and intramuscular fat development in Angus beef cattle 被引量:11
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作者 Corrine L.Harris Bo Wang +6 位作者 Jeneane M.Deavila Jan R.Busboom Martin Maquivar Steven M.Parish Brent McCann Mark L.Nelson Min Du 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第4期991-999,共9页
Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesi... Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesis). As intramuscular adipogenesis is active during the neonatal stage, we hypothesized that vitamin A administration during the neonatal stage would enhance intramuscular adipogenesis and marbling.Methods: Angus steer calves(n = 30), in a completely randomized design, were randomly allotted to three treatment groups at birth, receiving 0, 150,000, or 300,000 IU of vitamin A at both birth and one month of age.A biopsy of the biceps femoris muscle was collected at two months of age. After weaning at 210 d of age, steers were fed a backgrounding diet in a feedlot until 308 d of age, when they were transitioned to a high concentrate finishing diet and implanted with trenbolone/estradiol/tylosin mixture. Steers were harvested at an average of 438 d of age. All diets were formulated to meet nutrient requirements.Results: Weaning weight and weight during the backgrounding phase were linearly increased(P < 0.05) by vitamin A level, though no difference in body weight was observed at harvest. Intramuscular fat of steers at 308 d of age, measured by ultrasound, quadratically increased(P < 0.05) with vitamin A level from 4.0±0.26 % to 4.9±0.26 %.Similarly, carcass marbling score in the ribeye quadratically increased(P < 0.05).Conclusion: Administration of vitamin A at birth increased weaning weight and enhanced marbling fat development.Thus, vitamin A administration provides a practical method for increasing marbling and early growth of beef cattle. 展开更多
关键词 BEEF CALF CATTLE Marbling fat Quality Vitamin A
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The Tashisayi nephrite deposit from South Altyn Tagh, Xinjiang,northwest China 被引量:7
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作者 Kong Gao Guanghai Shi +6 位作者 Meili Wang Gen Xie Jian Wang Xiaochong Zhang Ting Fang Weiyan Lei Yan Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1597-1612,共16页
The Tashisayi nephrite deposit is located in South Altyn Tagh.in Qiemo County,Xinjiang Province,northwest China.It is a recent discovery in the vast,well-known Kunlun-Altyn nephrite belt distributed along the south of... The Tashisayi nephrite deposit is located in South Altyn Tagh.in Qiemo County,Xinjiang Province,northwest China.It is a recent discovery in the vast,well-known Kunlun-Altyn nephrite belt distributed along the south of the Tarim Basin,producing more than half of the nephrite from the whole belt in 2017.Field investigations revealed that it is a dolomitic marble-related(D-type)nephrite deposit,but little is known about its age of formation and relationships between the granites and marble.Here we report field investigations,petrography of the neph rite,as well as petrography,geochemistry,geochronology of the zoisite-quartz altered intrusive rock and adjacent granites.An A-type granite is identified with a SHRIMP U-Pb zircon age of 926±7 Ma,suggesting it was emplaced in an extensional tectonic environment at that time.The altered intrusive rock has a cluster of U-Pb zircon age of 433±10 Ma.with similar trace element features to the A-type granite,suggesting it was formed in an extensional regime at this later time.Nephrite formed because of the metasomatism of dolomite marble by hydrothermal fluids.It is inferred that Ca^2+was released from the dolomitic marble by metasomatism forming Ca-rich fluids,which caused alteration of both the intrusive rocks(6.00-8.22 wt.%CaO)and granite(1.76-3.68 wt.%CaO)near the nephrite ore bodies.It is also inferred that Fe^2+from the granite migrated towards the dolomite marble.The fluids gave rise to the formation of Ca-minerals.such as zoisite,in the nephrite and altered intrusive rock,and epidote in the granite.Based on the contact relationships.similarity in hydrothermal processes,and consumption of Ca^2+,the Tashisayi nephrite is considered to have formed at the same time as the alteration of the intrusive rocks,i.e.~433 Ma.The geochronological similarity(~926 Ma.433 Ma)of South Altyn and North Qaidam may suggest that tectonically they belong to one single complex in the past,which was offset by the Altyn Tagh fault(ATF).The similar formation ages of the nephrites from Altyn Tagh(433 Ma)and the previously studied areas of West Kunlun(378-441 Ma)and East Kunlun(416 Ma)indicate that these nephrites formed during the closure of Proto-Tethys and in the accompanving post-collisional.extensional environment. 展开更多
关键词 NEPHRITE DOLOMITE MARBLE A-TYPE granite Altyn Tagh fault Zircon U-PB dating
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Acoustic emission activity in directly tensile test on marble specimens and its tensile damage constitutive model 被引量:12
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作者 Ruifu Yuan Bowen Shi 《International Journal of Coal Science & Technology》 EI 2018年第3期295-304,共10页
For understanding acoustic emission (AE) activity and accumulation of micro-damage inside rock under pure tensile state, the AE signals has been monitored on the test of directly tension on two kinds of marble speci... For understanding acoustic emission (AE) activity and accumulation of micro-damage inside rock under pure tensile state, the AE signals has been monitored on the test of directly tension on two kinds of marble specimens. A tensile constitutive model was proposed with the damage factor calculated by AE energy rate. The tensile strength of marble was discrete obviously and was sensitive to the inside microdefects and grain composition. With increasing of loading, the tensile stress-strain curve obviously showed nonlinear with the tensile tangent modulus decreasing. In repeated loading cycle, the tensile elastic modulus was less than that in the previous loading cycle because of the generation of micro damage during the prior loading. It means the linear weakening occurring in the specimens. The AE activity was corresponding with occurrence of nonlinear deformation. In the initial loading stage which only elastic deformation happened on the specimens, there were few AE events occurred; while when the nonlinear deformation happened with increasing of loading, lots of AE events were generated. The quantity and energy of AE events were proportionally related to the variation of tensile tangent modulus. The Kaiser effect of AE activity could be clearly observed in tensile cycle loading. Based on the theory of damage mechanics, the damage factor was defined by AE energy rate and the tensile damage constitutive model was proposed which only needed two property constants. The theoretical stress-strain curve was well fitted with the curve plotted with tested datum and the two property constants were easily gotten by the laboratory testing. 展开更多
关键词 Marble specimens Direct tensile test Acoustic emission Tensile tangent modulus Damage constitutive model
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