维普中文期刊产品整合服务
249篇 您的检索式:关键字=GRAPHITE
    题名 作者 年代 出处 被引量
1Internal structure of Longmenshan fault zone at Hongkou outcrop,Sichuan,China,that caused the 2008 Wenchuan earthquake显示文摘This paper reports the internal structures of the Beichuan fault zone of Longmenshan fault system that caused the 2008 Wenchuan earthquake,at an outcrop in Hongkou,Sichuan province,China.Present work is a part of comprehensive project of Institute of Geology,China Earthquake Administration,trying to understand deformation processes in Longmenshan fault zones and eventually to reproduce Wenchuan earthquake by modeling based on measured mechanical and transport properties.Outcrop studies could be integrated with those performed on samples recovered from fault zone drilling,during the Wenchuan Earthquake Fault Scientific Drilling(WFSD) Project,to understand along-fault and depth variation of fault zone properties.The hanging wall side of the fault zone consists of weakly-foliated,clayey fault gouge of about 1 m in width and of several fault breccia zones of 30-40 m in total width.We could not find any pseudotachylite at this outcrop.Displacement during the Wenchuan earthquake is highly localized within the fault gouge layer along narrower slipping-zones of about 10 to 20 mm in width.This is an important constraint for analyzing thermal pressurization,an important dynamic weakening mechanism of faults.Overlapping patterns of striations on slickenside surface suggest that seismic slip at a given time occurred in even narrower zone of a few to several millimeters,so that localization of deformation must have occurred within a slipping zone during coseismic fault motion.Fault breccia zones are bounded by thin black gouge layers containing amorphous carbon.Fault gouge contains illite and chlorite minerals,but not smectite.Clayey fault gouge next to coseismic slipping zone also contains amorphous carbon and small amounts of graphite.The structural observations and mineralogical data obtained from outcrop exposures of the fault zone of the Wenchuan earthquake can be compared with those obtained from the WFSD-1 and WFSD-2 boreholes, which have been drilled very close to the Hongkou outcrop.The presence of carbon and graphite,observed next to the slipping-zone,may affect the mechanical properties of the fault and also provide useful information about coseismic chemical changes.Tetsuhiro Togo Toshihiko Shimamoto Shengli Ma Xueze Wen Honglin He 2011Earthquake Science2011,24,3:19
2The critical role of carbon in marrying silicon and graphite anodes for high-energy lithium-ion batteries显示文摘Increasing the energy density of conventional lithium-ion batteries(LIBs)is important for satisfying the demands of electric vehicles and advanced electronics.Silicon is considered as one of the most-promising anodes to replace the traditional graphite anode for the realization of high-energy LIBs due to its extremely high theoretical capacity,although its severe volume changes during lithiation/delithiation have led to a big challenge for practical application.In contrast,the co-utilization of Si and graphite has been well recognized as one of the preferred strategies for commercialization in the near future.In this review,we focus on different carbonaceous additives,such as carbon nanotubes,reduced graphene oxide,and pyrolyzed carbon derived from precursors such as pitch,sugars,heteroatom polymers,and so forth,which play an important role in constructing micrometersized hierarchical structures of silicon/graphite/carbon(Si/G/C)composites and tailoring the morphology and surface with good structural stability,good adhesion,high electrical conductivity,high tap density,and good interface chemistry to achieve high capacity and long cycling stability simultaneously.We first discuss the importance and challenge of the co-utilization of Si and graphite.Then,we carefully review and compare the improved effects of various types of carbonaceous materials and their associated structures on the electrochemical performance of Si/G/C composites.We also review the diverse synthesis techniques and treatment methods,which are also significant factors for optimizing Si/G/C composites.Finally,we provide a pertinent evaluation of these forms of carbon according to their suitability for commercialization.We also make far-ranging suggestions with regard to the selection of proper carbonaceous materials and the design of Si/G/C composites for further development.Jingxing Wu Yinliang Cao Haimin Zhao Jianfeng Mao Zaiping Guo 2019Carbon Energy2019,1,1:18
3Purification,application and current market trend of natural graphite:A review显示文摘Graphite has a stacked planar sp2-hybridized C6 ring structure,displaying a polymorphism with rhombohedral,hexagonal,and turbostratic.Based on its structure-property relationship,it affords a variety of technologically innovative applications or performances in industries,such as lithium-ion batteries,fuel cells,two dimensional graphene,water purification,electronics,fiber optics,spintronics,refractories,electrical products,electric vehicles,etc.The monetary value of graphite depends largely on carbon content and flake size.However,the physical separation of graphite from its ore body is known to be very expensive,energy intensive and time-consuming.Hence,this study extensively describes a current purification method for producing high-quality graphite material with impurities reaching about 10–100 mg/kg,attracting a lot of end users.It also describes the potential applications of graphite materials and identifies the future scope of a new market,depending on material purity.Finally,the current and future graphite-mining countries are investigated in details.Allah D.Jara Amha Betemariam Girma Woldetinsae Jung Yong Kim 2019International Journal of Mining Science and Technology2019,29,5:17
4Characteristics of thermally-enhanced bentonite grouts for geothermal heat exchanger in South Korea显示文摘The thermal conductivity and viscosity of bentonite grouts have been evaluated and compared each other to determine the suitability of these materials for backfilling vertical boreholes of ground heat exchangers.Seven bentonite grouts from different product sources were considered in this paper.Two additives,silica sand and graphite were added in bentonite grouts to enhance thermal performance.The bentonite grouts indicate that both the thermal conductivity and the viscosity increase with the content of silica sand and graphite.Therefore,it is recommended to select cautiously the amount of silica sand and graphite considering not only thermal conductivity but also viscosity for the optimum condition of backfilling.Finally,the effect of salinity in the pore water on the change of swelling potential of the bentonite-based grouts has been quantitatively evaluated to show the feasibility of bentonite grouts in the coastal area.Chulho LEE Kangja LEE Hangseok CHOI Hyo-Pum CHOI 2010Science China(Technological Sciences)2010,53,1:16
5Studies on photo-electro-chemical catalytic degradation of acid scarlet 3R dye显示文摘A new type of photo-electro-chemical catalytic reactor was designed.Cathode and anode of the new reactor were made of high-purity graphite and titanium dioxide electrode re-spectively.A saturated calomel electrode (SCE) was used as the reference electrode.Under the condition of ultraviolet radiation and anodic bias-voltage,acid scarlet 3R was degraded by the process of photoelectrocatalysis with titanium dioxide electrode in anodic compartment,while it was degraded by electrogenerated Fenton’s reagent and hydrogen peroxide through reducing dissolved oxygen with graphite electrode in catholyte.The new reactor made the best use of photogenerated holes and photogenerated charge on the anode of the new reactor,which achieved the purpose of degrading acid scarlet 3R in the cathodic and anodic compartments simultaneously,i.e.“two electrodes and double effect”.The experimental results showed that,compared with other photoelectrocatalysis reactors (“two electrodes and single effect” reactor),the new reactor has obviously enhanced the degradation of acid scarlet 3R dye.With the con-centration of the dye being 30 mg·L?1 in water,under the operating conditions that when the inert supporting electrolyte concentration was 0.02 mol·L?1 sodium sulfate,initial solution pH = 3,and cathodic potential ?Ec = 0.66 V,the highest decolorizing efficiency of 92% was accomplished in cathodic compartment,and that of 60% in anodic compartment.LI Mingyu1,XIONG Lin1,CHEN Yunyun2,ZHANG Na1,ZHANG Yuanming2 & YIN Hua1 1.Department of Environmental Engineering,Jinan University,Guangzhou 510630,China 2.Department of Chemistry,Jinan University,Guangzhou 510630,China 2005Science China Chemistry2005,48,4:13
6Status and challenges facing representative anode materials for rechargeable lithium batteries显示文摘Rechargeable lithium batteries have been widely regarded as a revolutionary technology to store renewable energy sources and extensively researched in the recent several decades.As an indispensable part of lithium batteries,the evolution of anode materials has significantly promoted the development of lithium batteries.However,since conventional lithium batteries with graphite anodes cannot meet the ever-increasing demands in different application scenarios(such as electric vehicles and large-scale power supplies)which require high energy/power density and long cycle life,various improvement strategies and alternative anode materials have been exploited for better electrochemical performance.In this review,we detailedly introduced the characteristics and challenges of four representative anode materials for rechargeable lithium batteries,including graphite,Li_(4)Ti_(5)O_(12),silicon,and lithium metal.And some of the latest advances are summarized,which mainly contain the modification strategies of anode materials and partially involve the optimization of electrode/electrolyte interface.Finally,we make the conclusive comments and perspectives,and draw a development timeline on the four anode materials.This review aims to offer a good primer for newcomers in the lithium battery field and benefit the structure and material design of anodes for advanced rechargeable lithium batteries in the future.Liqiang Zhang Chenxi Zhu Sicheng Yu Daohan Ge Haoshen Zhou 2022Journal of Energy Chemistry2022,31,3:13
7Synthesis of Alumina-Coated Natural Graphite for Highly Cycling Stability and Safety of Li-Ion Batteries显示文摘The natural graphite(NG)urdformly coated with alumina ceramics(Al2O3)was successfully synthesized through sol-gel method.The aluminum plastic film soft-packed battery prepared using Al2O3-coated NG as anode material exhibits excellent cycle performance and safety performance.The cycling retention of AN-1 is 84.95% after 200 cycles at a rate of 1 C in a potential window ranging from 3.0 to 4.35 V,which is much greater than 75.07% of NG under the same test conditions.The result of the nail penetration tests shows that the successful nail penetration rate of the NG used as anode is 0%,while that of Al2O3 coated samples AN-1 is 100%.The test results show that the Al2O3 coating could act as a solid electrolyte to suppress side reactions,improve cycle stability,and prevent a thermal runaway under mechanical abuse.Tao Xu Chengkun Zhou Haihui Zhou Zekun Wang Jianguo Ren 2019Chinese Journal of Chemistry2019,37,4:13
8Perspective on the critical role of interface for advanced batteries显示文摘As an efficient and environmental friendly energy storage system, lithium battery has been integrated into daily mobile life [1].Lithium batteries are becoming indispensable to all types of electronic products such as laptop computers, mobile phones, digital cameras [2]. A typical lithium battery consists of positive electrode(cathode), negative electrode(anode), electrolyte and other inactive materials(binder, conductive agent, separator) [3].Chong Yan Hong Yuan Ho Seok Park Jia-Qi Huang 2020Journal of Energy Chemistry2020,29,8:12
9Mineral association and graphite inclusions in nephrite jade from Liaoning, northeast China: Implications for metamorphic conditions and ore genesis显示文摘The Liaoning Province in the northeastern part of the North China Craton(NCC) hosts several tremolite jade(nephrite) deposits. Here we investigate the Sangpiyu tremolite jade deposit where the relationship between abundant graphite inclusions within the jade remains enigmatic. We employ petrography, electron probe microanalysis, X-ray-diffraction, and Raman spectroscopy to characterize the tremolite jade and its inclusion minerals. The Sangpiyu jade is predominately composed of tremolite with minor calcite, dolomite, serpentine, titanite, zoisite, allanite, chlorite,apatite, chromite and graphite. Raman spectroscopy of graphite inclusions shows that the D1/G intensity ratio ranges from 0.78 to 0.88 in deep green samples and from 0.05 to 0.23 in dark green samples. The ranges of D1/(D1 + G) integral area ratio for these types are from 0.0548 to 0.3037 and 0.5528 to 0.7355 respectively. The formation temperature of graphite inclusions in the dark green tremolite jade is computed as 549.8 ℃, whereas that for the deep green sample is about343.2 ℃. Our results suggest that the jade formation occurred in a multi-stage process through the action of hydrothermal fluids and metamorphism possibly in a subduction-related setting at moderate to high temperatures.Cun Zhang Xiaoyan Yu Tianlong Jiang 2019Geoscience Frontiers2019,10,2:11
10Compacted graphite iron-A material solution for modern diesel engine cylinder blocks and heads显示文摘The demands for improved fuel economy,performance and emissions continue to pose challenges for engine designers and the materials they choose. This is particularly true for modern diesel engines,where the primary path to achieving improved engine performance and emissions is to increase the Peak Firing Pressure in the combustion chamber. The resulting increase in thermal and mechanical loading has required a change from conventional grey cast iron to Compacted Graphite Iron (CGI) in order to satisfy durability requirements without increasing the size or the weight of the engines. With at least 75% higher tensile strength,45% higher stiffness and approximately double the fatigue strength of conventional grey cast iron,CGI satisfies durability requirements and also provides the dimensional stability required to meet emissions legislation throughout the life of the engine. Currently,there are no CGI diesel engines running on the roads in North America. This is set to change considerably as new commercial vehicle and pick-up SUV diesel engines are launched with CGI cylinder blocks in 2008 and 2009. These initial programs will provide over 2 million CGI diesel engines when ramped to mature volume,potentially accounting for 10%-15% of the North American passenger vehicle fleet within the next four years.Steve Dawson SinterCast Sweden 2009China Foundry2009,6,3:11
11RESEARCH ON THE APPLICATION OF RARE EARTHS IN IRON AND STEEL IN RECENT YEARS显示文摘China has the biggest rare earths resource in the world,no wonder she pays much at-tention to the application of rare earth metals (REM).The application of REM in iron andsteel in China began at the end of 1950’s.The production of REM-treated iron and steelhad been made steady progress in the period of 1980’s.The production of REM-treatediron and steel in 1989 was 1.4 million tons and 250,000 tons respectively.The interest oftreating steel with REM in China keeps growing even in these years,It comes from the nat-余宗森 1990Journal of Rare Earths1990,8,2:10
12Geological characteristics, metallogenic regularities and the exploration of graphite deposits in China显示文摘The demand for graphite resources has been increasing due to its extensive use.Graphite deposits in China are mainly distributed in Heilongjiang,Innner Mogolia,Sichuan,Shanxi and Shandong,characterized by 'one old & one new' and 'many in east & few in west'.There are mainly three genetic types,including regional metamorphic type,contact metamorphic type and hydrothermal type.Here we provide a summary of the metallogenic regularity and 15 metallogenic belts in China based on the study of the geology of national graphite deposits.In recent years,great progress has been made in the research of genesis,mineral exploration and evaluation on graphite deposits,which indicate great potential for graphite resource in China.The authors suggest that the research on geochronology,ore sources,the genesis of crystalline graphite and exploration for hydrothermal graphite in China should be heightened.Li Sun Cui-ping Xu Ke-yan Xiao Yu-sheng Zhu Ling-ya Yan 2018China Geology2018,1,3:9
13An innovative flake graphite upgrading process based on HPGR,stirred grinding mill, and nanobubble column flotation显示文摘Physical upgrading of graphite is typically achieved with many stages of grinding and flotation to produce a concentrate with approximately 95% carbon grade.An innovative grinding and column flotation process has been developed for efficient graphite upgrading to substantially simplify the process flowsheet and reduce operating costs.In this process,a high-pressure grinding roller(HPGR) and a stirred mill were employed as primary comminution techniques and a nanobubble flotation column as a key separation process.The results obtained with a crystalline flake graphite sample with a carbon grade of 11.15% show that the novel process can produce a concentrate with 94.82% carbon grade and 97.89% recovery from an open circuit of one rougher and two cleaner flotation stages.Scanning electron microscope(SEM)microphotographs indicate that HPGR offers the advantage of more effective protection of graphite flakes during crushing.Grinding test results show that stirred mill could not only protect graphite flakes but also promote the efficient liberation of graphite.Compared with the traditional flotation process,nanobubble flotation can effectively recover ultrafine graphite.The new process possesses a number of important advantages over the traditional method,including substantially higher graphite recovery,greatly simplified process flowsheet,better protection of flake size,reduced reagent consumption and process costs,etc.Fangyuan Ma Dongping Tao Youjun Tao Shuyong Liu 2021International Journal of Mining Science and Technology2021,31,6:9
14A super-large graphite deposit discovered in granite rocks at Huangyangshan, Xinjiang,China显示文摘1.Objective A graphite deposit has been discovered in Sujiquan, Xinjiang in 1980s,which provides detailed geological settings for the super-large graphite deposit discovered in Huangyangshan pluton with total reserves up to 7.264×10^9 t in 2017.Outcrops of igneous rocks in the study area include Middle Devonian plagioclase granite and Late Carboniferous alkali feldspar granite that is referred to the Huangyangshan pluton,which includes the Lower Carboniferous Heishantou Formation and Jiangbasi Formation,both of which consist of volcanic-sedimentary rocks (Fig.1).Sujiquan fault provided passage for the migration of volcanic intrusions.Graphite deposits are usually hosted by metamorphic rocks,but Huangyanshan deposits are hosted by granite rocks,which are rarely known.The Huangyangshan graphite deposit hosted by granite pluton at Huangyangshan area was discovered by Xinjiang Branch of China National Geological Exploration Center of Building Materials Industry since 2015.Jiang Ai Xin-biao Lu Zuo-wu Li Ya-lun Wu 2018China Geology2018,1,1:9
15Closed-loop hydrometallurgical treatment of end-of-life lithium ion batteries: Towards zero-waste process and metal recycling in advanced batteries显示文摘This work presents an enhanced hydrometallurgical process for recycling lithium ion batteries. First, endof-life batteries were processed in a physical pre-treatment plant to obtain a representative electrode material. The resulting leachate was purified forth by iron-precipitation, liquid–liquid extractions, and an innovative Li–Na separation, in order to obtain valuable products. These products include high-grade graphite, cobalt oxide(Co3O4, purity 83%), cobalt oxalate(CoC2O4, purity 96%), nickel oxide(Ni O, purity89%), and lithium carbonate(Li2CO3, purity 99.8%). The recovery rate was quantitative for graphite, between 80% and 85% for cobalt depending on the nature of the recovery method, 90% for nickel, and 72%for lithium. Secondary streams were also valorized to obtain sodium sulfate(Na2SO4, purity 96%), and MnCoFe2O4 magnetic nano-sorbents according to the zero-waste concept. In order to close the loop, recycled Co3O4 and NiO were used as conversion-type anode materials for advanced lithium ion batteries showing promising performances.Thomas Abo Atia Giuseppe Elia Robert Hahn Pietro Altimari Francesca Pagnanelli 2019Journal of Energy Chemistry2019,28,8:8
16Thermal conductivity of cast iron-A review显示文摘This paper gives a brief introduction to the four research methods for the study on thermal conductivity of cast irons,including experimental measurement,statistical analysis,effective medium theory and numerical simulation.Recent studies on the thermal conductivity of various cast irons are reviewed through the influence of alloying elements,structural constituents,and temperature.The addition of alloying elements is the main reason that restricts the thermal conductivity of cast irons,especially spheroidal graphite cast iron.The connectivity of graphite has a significant effect on the thermal conductivity of flake and compacted graphite cast irons,semiquantitative and quantitative analysis of this factor is a key and difficult point in the study of thermal conductivity of cast irons.The thermal conductivities of different types of cast irons show varying degrees of dependence on temperature.This phenomenon is the combination of graphite and matrix,rather than just depending on graphite morphology.The study of the relationship between individual phase and temperature is the focus of future research.These summaries and discussions may provide reference and guidance for the future research and development of high thermal conductivity cast irons.Guang-hua Wang Yan-xiang Li 2020China Foundry2020,17,2:7
17Conductive Polyaniline/Cellulose/Graphite Composite Films with High Thermal Stability and Antibacterial Activity显示文摘Functional composite films were successfully prepared from cellulose, graphite(GP), and polyaniline(PANI) using a combination of physical and chemical processes. Cellulosewasdissolved in N-methylmorpholine-N-oxide monohydrate(NMMO) and regenerated in water to form the matrix. GP was dispersed in the NMMO solvent prior to the dissolution of the cellulose, and PANI was deposited on the surfaces of the cellulose/GP films by in situ chemical polymerization. The structures of the PANI/cellusose/GP composite films were investigated using X-ray diffraction analysis, Fourier transform infrared spectroscopy, scanning electron microscopy(SEM), and SEM/energy-dispersive X-ray spectroscopy. The mechanical strengths, thermal stabilities, conductivities, and antibacterial activities of the films were studied in detail. The results showed that GP formed a multilayered structure in the cellulose matrix and that the PANI nanoparticles were tightly wrapped on the film surface. The film thickness increased from 40 mm to 100 mm after the addition of GP and PANI. The tensile strength of the composite films was 80~107 MPa, with the elongation at break being 3%~10%. The final residual weight of the composite films was as high as 65%, and the conductivity of the composite films reached 14.36 S/m. The cellulose matrix ensured that the films were flexible and exhibited desirable mechanical properties, while the GP filler significantly improved the thermal stability of the films. The PANI coating acted as a protective layer during burning and provided good electrical conductivity and antibacterial activity against Escherichia coli; both of these characteristics were slightly enhanced by the incorporation of GP. These PANI/cellulose/GP composite films should be suitable for use in electronics, antistatic packing, and numerous other applications.JingHuan Chen JinGang Liu WenTao Zhang Kun Wang XueRen Qian RunCang Sun 2017Paper And Biomaterials2017,2,1:7
18Synthesis of graphene materials by electrochemical exfoliation: Recent progress and future potential显示文摘Synthesis of structurally controlled graphene materials is critical for realizing their practical applications.The electrochemical exfoliation of graphite has emerged as a simple method to produce graphene materials.This review examines research progress in the last 5 years,from 2015 to 2019.Graphene material synthesis methods generally have a trade‐off between increasing production yield and achieving better material property control.The synthesis conditions for synthesizing pristine graphene,graphene oxide(GO),and graphene composites are significantly different.Thus,in this review,we first discuss synthesis methods for graphene materials with high C/O ratios from four aspects:graphite electrodes,equipment engineering,electrolytes,and additional reduction methods.Next,we survey synthesis methods for GO and examine how the pretreatment of the graphite electrodes,electrolytes,and operation parameters,such as applied voltages,electrolyte temperatures,and mechanical forces,affect the quality of GO.Further,we summarize electrochemical exfoliation methods used to dope graphene materials,introduce covalent functional groups,incorporate various nanoparticles,and assembly of graphene architectures.For all synthesis methods,we compare the properties of resulting graphene materials such as C/O ratios,lateral size,layer numbers,and quality characterized by Raman spectroscopy.Lastly,we propose our perspectives on further research.We hope this review stimulates more studies to realize the on‐demand production of graphene materials with desired properties using electrochemical exfoliation methods.Fei Liu Chaojun Wang Xiao Sui Muhammad Adil Riaz Meiying Xu Li Wei Yuan Chen 2019Carbon Energy2019,1,2:6
19Feasible engineering of cathode electrolyte interphase enables the profoundly improved electrochemical properties in dual-ion battery显示文摘Dual-ion battery(DIB) composed of graphite cathode and lithium anode is regarded as an advanced secondary battery because of the low cost, high working voltage and environmental friendliness. However,DIB operated at high potential(usually ≥ 4.5 V versus Li+/Li) is confronted with severe challenges including electrolyte decomposition on cathode interface, and structural deterioration of graphite accompanying with anions de-/intercalation, hinder its cyclic life. To address those drawbacks and preserve the DIB virtues, a feasible and scalable surface modification is achieved for the commercial graphite cathode of mesocarbon microbead. In/ex-situ studies reveal that, such an interfacial engineering facilitates and reconstructs the formation of chemically stable cathode electrolyte interphase with better flexibility alleviating the decomposition of electrolyte, regulating the anions de-/intercalation behavior in graphite with the retainment of structural integrity and without exerting considerable influence on kinetics of anions diffusion. As a result, the modified mesocarbon microbead exhibits a much-extended cycle life with high capacity retention of 82.3% even after 1000 cycles. This study demonstrates that the interface modification of electrode and coating skeleton play important roles on DIB performance improvement, providing the feasible basis for practical application of DIB owing to the green and scalable coating procedures.Wen-Hao Li Hao-Jie Liang Xian-Kun Hou Zhen-Yi Gu Xin-Xin Zhao Jin-Zhi Guo Xu Yang Xing-Long Wu 2020Journal of Energy Chemistry2020,29,11:6
20Novel flexible broadband microwave absorptive fabrics coated with graphite nanosheets/polyurethane nanocompositesMiao-miao Yu Shao-hua Chen Zhe Zhou Mei-fang Zhu 2012Progress in Natural Science:Materials International2012,22,4:6
返回顶部 每页显示:
共13页 首页 上一页 第1页 下一页 末页 /13 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费