Nanshu Town is a famous graphite town of Laixi City. Nanshu Town has 46 graphite enterprises with scattered distribution, incomplete industry chain, low output, and low value-added. In order to exert the resources adv...Nanshu Town is a famous graphite town of Laixi City. Nanshu Town has 46 graphite enterprises with scattered distribution, incomplete industry chain, low output, and low value-added. In order to exert the resources advantage, Nanshu Town has planed and builta building materials zone covering 800 thousand square meters since 2010. Kaonuo Ceramics, a key project of Qingdao City, was building here. Three deep-processing projects of graphite new materials with the total investment of CNY 480 million will be built in this zone.展开更多
The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock reactions.Learning how to collect age data on hydrothermal fluid systems is necessary for understanding ...The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock reactions.Learning how to collect age data on hydrothermal fluid systems is necessary for understanding the history and genetic mechanisms of large-scale coal-generated graphite deposits.The Shihangli graphite deposit,formed by significant siliceous hydrothermal alteration,is the most distinctive in Central Hunan.Re–Os dating of pyrite from the Shihangli graphite deposit demonstrates that the coal-generated graphite mineraliza-tion age is-127.6±3.8 Ma.Based on in-situ mineral analysis,the hydrothermal pyrite in the Shihangli graphite deposit is mostly enriched in Sb,As,Au,W,Ag,Cu,Pb,and Zn.Based on the pyrite Re–Os isochron,the initial(^(187)Os/^(188)Os)values of pyrite were 1.03±0.24 and the Os(t)values varied from 571.8 to 755.1.Pyrite from the Shihangli graphite deposit comprises a Pb isotope composition similar to that of the Madiyi Formation bulk rock and stibnite from the Xikuangshan Sb deposit.Based on the Re–Os,Sr,S,and Pb isotopic compositions of sul-fides in the graphite and Sb deposits in Central Hunan,the Madiyi Formation was likely the primary source of ore-forming elements(Sb,Au,and As).The Re–Os and Pb isotope compositions of pyrite most likely reflect when large-scale fluid migration and coal-generated graphite mineralization occurred in Central Hunan.展开更多
As an alternative to lithium-ion batteries,aqueous zinc-graphite batteries(ZnGBs)are being explored as safer and low-cost options with the expectation of scalability to large energy storage systems.However,the current...As an alternative to lithium-ion batteries,aqueous zinc-graphite batteries(ZnGBs)are being explored as safer and low-cost options with the expectation of scalability to large energy storage systems.However,the currently adopted polyatomic and metal complex anion intercalation process at the graphite electrode in ZnGB exhibits poor electrochemical performances.Alternatively,incorporating halogen anions offers exceptional electrochemical performance to graphite electrodes due to their redox process.In this work,ZnGBs are assembled using a LiCl/ZnCl2/KBr^(-)based water-in-salt electrolyte,which efficiently supplies bromide(Br^(−))ions for conversion into Br_(x)^(−)and facilitates Br_(2)intercalation at the graphite electrode.The conversion and intercalation of bromine together enable the ZnGB to achieve a discharge capacity of 2.73 mAh/cm^(2)with 91.0%of coulombic efficiency(CE)while supporting high current density operations of up to 150 mA/cm^(2).With high energy density(4.56 Wh/cm^(2)),high power density(199.5 mW/cm^(2)),and excellent rate capability(∼93.0%CE at 150 mA/cm^(2)),the ZnGB is shown to operate efficiently for as much as 800 cycles.Beguilingly,an anode-free ZnGB offers enhanced stability for up to 1100 cycles without performance decay,matching the electrochemical performance of Zn metal electrodes.This work provides insights into the bromine reaction mechanism at graphite electrodes and the role of surface exfoliation in enabling efficient Br_(x)^(−)formation,along with Br_(2)intercalation,for achieving high-performance ZnGBs.展开更多
Graphite,encompassing both natural graphite and synthetic graphite,and graphene,have been extensively utilized and investigated as anode materials and additives in lithium-ion batteries(LIBs).In the pursuit of carbon ...Graphite,encompassing both natural graphite and synthetic graphite,and graphene,have been extensively utilized and investigated as anode materials and additives in lithium-ion batteries(LIBs).In the pursuit of carbon neutrality,LIBs are expected to play a pivotal role in reducing CO_(2)emissions by decreasing reliance on fossil fuels and enabling the integration of renewable energy sources.Owing to their technological maturity and exceptional electrochemical performance,the global production of graphite and graphene for LIBs is projected to continue expanding.Over the past decades,numerous researchers have concentrated on reducing the material and energy input whilst optimising the electrochemical performance of graphite and graphene,through novel synthesis methods and various modifications at the laboratory scale.This review provides a comprehensive examination of the manufacturing methods,environmental impact,research progress,and challenges associated with graphite and graphene in LIBs from an industrial perspective,with a particular focus on the carbon footprint of production processes.Additionally,it considers emerging challenges and future development directions of graphite and graphene,offering significant insights for ongoing and future research in the field of green LIBs.展开更多
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,...Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.展开更多
In order to effectively prevent the contamination of carbon particle volatiles during high-purity SiC crystals are prepared using the physical vapor transport(PVT)method in ultra-high temperature environments(T³2...In order to effectively prevent the contamination of carbon particle volatiles during high-purity SiC crystals are prepared using the physical vapor transport(PVT)method in ultra-high temperature environments(T³2000℃),this study innovatively attempts to protect graphite materials with SiC reinforced pyrolytic graphite(PyG)coating.It is discovered by preparing the SiC particle layer,the degree of graphitization and stability of PyG coating can be improved.The corrosion test results demonstrated that the SiC reinforced PyG coating can maintain an intact coating with a high graphitization degree after the SiC vapour corrosion test of 2050℃-120 h.Conversely,the samples with and without PyG coating reveal porous and eroded surfaces.Furthermore,following the SiC vapour corrosion test,the PyG coating sample’s integral ratio of D-band and G-band(I_(D)/I_(G))of Raman spectrum test data,reduced by 6.5%,while the SiC reinforced PyG coating decreased by 17.2%,indicating its excellent corrosion resistance.The application of SiC reinforced pyrolytic graphite coating in preparing the SiC single crystal might received a theoretical foundation according to this work.展开更多
To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as wel...To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.展开更多
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral...Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.展开更多
Simultaneous identification and quantitative detection of phenylenediamine(PDA)isomers,including o-phenylenediamine(OPD),m-phenylenediamine(MPD),and p-phenylenediamine(PPD),are essential for environmental risk assessm...Simultaneous identification and quantitative detection of phenylenediamine(PDA)isomers,including o-phenylenediamine(OPD),m-phenylenediamine(MPD),and p-phenylenediamine(PPD),are essential for environmental risk assessment and human health protection.However,current visual detection methods can only distinguish individual PDA isomers and failed to identify binary or ternary mixtures.Herein,a highly active and ultrastable peroxidase(POD)-like CoPt graphitic nanozyme was used for naked-eye identification and colorimetric/fluorescent(FL)dual-mode quantitative detection of PDA isomers.The CoPt@G nanozyme effectively catalyzed the oxidation of OPD,MPD,PPD,OPD+PPD,OPD+MPD,MPD+PPD and OPD+MPD+PPD into yellow,colorless,lilac,yellow,yellow,wine red and reddish-brown products,respectively,in the presence of H_(2)O_(2).Thus,the MPD,PPD,MPD+PPD and OPD+MPD+PPD were easily identified based on the distinct color of their oxidation products,and the OPD,OPD+PPD,OPD+MPD could be further identified by the additional addition of MPD or PPD.Subsequently,CoPt@G/H_(2)O_(2)-,a 3,3′,5,5′-tetramethylbenzidine(TMB)/CoPt@G/H_(2)O_(2)-,and MPD/CoPt@G/H_(2)O_(2)-enabled colorimetric/FL dual-mode platforms for the quantitative detection of OPD,MPD and PPD were proposed.The experimental results illustrated that the constructed sensing platforms exhibit satisfactory sensitivity,comparable to that reported in previous studies.Finally,the evaluation of PDAs in water samples was realized,yielding satisfactory recoveries.This work expanded the application prospects of nanozymes in assessing environmental risks and protection of human security.展开更多
Waste graphitization cathode carbon blocks are a type of hazardous solid waste generated during the aluminum electrolysis process,and their proper disposal is a key step in the resource utilization of discarded graphi...Waste graphitization cathode carbon blocks are a type of hazardous solid waste generated during the aluminum electrolysis process,and their proper disposal is a key step in the resource utilization of discarded graphite.This study utilizes the porous“defect advantage”of a cathode carbon block matrix to prepare silicon-doped and asphalt-coated detoxified and purified waste graphitization cathode carbon blocks for use as high-performance silicon/carbon composite anode materials.The results show that the uniformly silicondoped silicon/carbon composite material features a unique amorphous carbon-encapsulated“locked silicon”structure,which effectively addresses issues such as cathode volume expansion,excessive growth of the solid electrolyte interphase(SEI)film,and poor electrical contact between active materials.Consequently,electrochemical performance is enhanced.After assembly in a half-cell,the PSCC/10%Si@C(purified waste graphitization cathode carbon/10%Si@C)material exhibits optimal electrochemical stability,with an initial charging specific capacity of 514.5 mAh/g at 0.1 C(1 C=170 mA/g)and a capacity retention rate of 95.1%after 100 cycles.At a charge rate of 2.0 C,a specific capacity of 216.9 mAh/g is achieved.This technology provides a new pathway for the economical and high-value utilization of waste cathode carbon blocks and the development of low-cost,high-performance anode materials.展开更多
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 abu...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.展开更多
The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Here...The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Herein,for estimating the carbon content in graphite,the ASTM-C561,the test method for ash in a graphite sample,was used.For characterizing graphite,x-ray diffraction,x-ray fluorescence,inductively coupled plasma mass spectroscopy,and scanning electron microscopy were also used.Chemical analysis of ore samples determined that the average compositions are 63.35%SiO2,15.45%Al2O3,2.36%Fe2O3,2.07%K2O,less than1%others,and loss-on-ignition(LOI)in the range of^4.74%–37.42%.The total carbon content of graphitic ore ranged from 4.11%to 33.14%.Importantly,when graphite is concentrated through floatation,its average purity and recovery are 92.97%and 90.82%,respectively.Furthermore,once the graphite concentrates are treated with hydrofluoric acid,the average value attains a high grade of 96.48%C.Moreover,the average ash content is 81.93%(pre-flotation)and 3.1%(post-flotation),respectively.Finally,after beneficiation,a silica is identified as a major gangue(85.88%),usable as a raw material for other purposes such as cement.Hence,these graphite-bearing rocks seem to be worth exploring for commercialization opportunities.展开更多
With the global rise of industries of the new-generation information technology, energy conservation and environmental protection, biotechnology, high-end manufacturing, new materials and clean-energy vehicles, tradit...With the global rise of industries of the new-generation information technology, energy conservation and environmental protection, biotechnology, high-end manufacturing, new materials and clean-energy vehicles, traditional metal materials cannot meet the functional requirements. Consequently, ＂three rare mineral resources＂, regarded as the best altemative for current and future new industries, have received much attention among industrial circles and have become a new focus during the present geological prospecting in China.展开更多
With the growing demand for faster and more powerful computing,effective heat dissipation is essential to ensure the longevity,reliability,and high performance of electronic systems.In the field of modern electronic p...With the growing demand for faster and more powerful computing,effective heat dissipation is essential to ensure the longevity,reliability,and high performance of electronic systems.In the field of modern electronic packaging materials,there is a great need for graphitic material-loaded polymeric composites(GPCs)with excellent thermal conductivities.However,the enhancement efficiency of GPCs is hindered by the agglomeration of fillers and the interfacial thermal resistance caused by the lack of continuous thermally conductive pathways between the filler and matrix.Understanding the interfaces between filler and matrix is of great importance in optimizing the performances of GPCs.Here,we fabricated graphite nanofibers(GNF)-loaded nanocomposites using acid-functionalized GNF(AGNF)and acidtetraethylenepentamine-functionalized(TGNF)as a filler and epoxy resin as a matrix with different GNF loading contents to explore the interfacial properties of the nanocomposites.The optimal GNF loading for AGNF was 0.5 wt.%,while the TGNF showed 0.75 wt.%.The highest thermal conductivity(0.51 W m^(−1) K^(−1))and fracture toughness(25.8 MPa m^(1/2))values were found in the TGNF-loaded nanocomposites with a fraction of 0.75 wt.%,representing enhancements of∼145%and∼400%,respectively,compared to those of neat nanocomposites.The experimental data presented herein demonstrate that the interfacial properties play a significant role in enhancing the thermal and mechanical performances of the nanocomposites.The present approach is expected to serve as a valuable tool in the design of conductive polymeric nanocomposites for further practical applications,such as thermal interface materials and packaging of high-power electric devices.展开更多
Graphite is naturally floatable due to its hydrophobic pro pe rty and also soft and smears on other gangue particles, rendering the gangue mor e or less floatable too. Due to this reason it is important to concentrate...Graphite is naturally floatable due to its hydrophobic pro pe rty and also soft and smears on other gangue particles, rendering the gangue mor e or less floatable too. Due to this reason it is important to concentrate on ar eas such as suitable flotation reagents, depression agents, pH modifiers, and pa rticle size to be fed during the process. The paper surveys and analyses the sui table particle size to be fed to achieve high-grade concentrate. According to t h e work carried out the author suggested the ideal cost effective flotation f low sheet for improved results at Bogala Mines in Sri Lanka.展开更多
In this paper,we introduced a novel method to prepare the few-layer nitrogen-doped graphene(FNG)from expandable graphite with melamine.The super-capacitive properties of FNG were thoroughly characterized by a three-el...In this paper,we introduced a novel method to prepare the few-layer nitrogen-doped graphene(FNG)from expandable graphite with melamine.The super-capacitive properties of FNG were thoroughly characterized by a three-electrode system,and the results showed the FNG electrode achieved a specific capacitance as high as 83.8 mF/cm2 together with excellent cycling stability.This method could be a novel approach to combine the pseudo-capacitors and electric double layer capacitors.展开更多
In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding s...In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam(RPUF).The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in RPUF.However,excessive EG was capable of reducing the fluidity of polyurethane slurry.TEA exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then increased.DMMP had a remarkable effect on the flame retardant property and compressive strength of RPUF.Compressive strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in foam.DMMP displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of RPUF.Moreover,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_2.The oxygen index and flowing length of foam increased with the increase in isocyanate dosage.展开更多
A novel nano-SnO2/graphite electrode has been prepared via polishing procedure to produce active and stable surface. The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbic acid...A novel nano-SnO2/graphite electrode has been prepared via polishing procedure to produce active and stable surface. The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbic acid into two well-defined peaks by 230 mV. The mechanism of discrimination of dopamine from ascorbic acid is discussed. Dopamine and ascorbic acid can be determined simultaneously with the modified electrode. The electrode shows good sensitivity, selectivity and stability.展开更多
A method for determination of epinephrine（EP） in the presence of ascorbic acid （AA） and dopamine （DA） with bare pyrolytic graphite electrodes has been described for the first time. In pH 7.0 phosphate buffer sol...A method for determination of epinephrine（EP） in the presence of ascorbic acid （AA） and dopamine （DA） with bare pyrolytic graphite electrodes has been described for the first time. In pH 7.0 phosphate buffer solution, the linear relationship was observed between the reduction peak current of EP and its concentration over the range from 1×10^-4 to 5×10^-7 mol/L, the related coefficient is 0.9992 （N=8）.展开更多
The mineralogical features of the oxidation-reduction of graphite deposit in pingdu, Shandong province were studied by field search, polarization microscope, X-ray diffraction (XRD) and SEM. The results show that, the...The mineralogical features of the oxidation-reduction of graphite deposit in pingdu, Shandong province were studied by field search, polarization microscope, X-ray diffraction (XRD) and SEM. The results show that, the major rocks of the reduction graphite zone are graphite-quartz anorthosite, gabbro. The major rocks of the oxidation graphite zone are marble with graphite, biotite granite, monzogranite. The main minerals of the reduction zone are plagioclase, pyroxene, quartz, pyrite. The graphite is aphanitic graphite appearing as dense massive, layered, spherical aggregates. The main minerals of the oxidation zone are calcite, quartz, K-feldspar, biotite, amphibole, chlorite. The graphite is flake graphite uniformly dispersed in the loose, and strongly erosion rocks. A large number of rocks in the area have been suffered chloritization, regional metamorphism, indicating that the formation of the graphite deposit should be related with gabbro melting. The carbon source in the lower part was taken into the mine, and then experienced regional metamorphism.展开更多
文摘Nanshu Town is a famous graphite town of Laixi City. Nanshu Town has 46 graphite enterprises with scattered distribution, incomplete industry chain, low output, and low value-added. In order to exert the resources advantage, Nanshu Town has planed and builta building materials zone covering 800 thousand square meters since 2010. Kaonuo Ceramics, a key project of Qingdao City, was building here. Three deep-processing projects of graphite new materials with the total investment of CNY 480 million will be built in this zone.
基金the National Key Research and Development Program of China(2016YFC0600207,2014CB440904)National Natural Science Foundation of China(Nos.42062006,41962007)the Integrated Exploration Project of China Geological Survey(No.12120114034501).
文摘The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock reactions.Learning how to collect age data on hydrothermal fluid systems is necessary for understanding the history and genetic mechanisms of large-scale coal-generated graphite deposits.The Shihangli graphite deposit,formed by significant siliceous hydrothermal alteration,is the most distinctive in Central Hunan.Re–Os dating of pyrite from the Shihangli graphite deposit demonstrates that the coal-generated graphite mineraliza-tion age is-127.6±3.8 Ma.Based on in-situ mineral analysis,the hydrothermal pyrite in the Shihangli graphite deposit is mostly enriched in Sb,As,Au,W,Ag,Cu,Pb,and Zn.Based on the pyrite Re–Os isochron,the initial(^(187)Os/^(188)Os)values of pyrite were 1.03±0.24 and the Os(t)values varied from 571.8 to 755.1.Pyrite from the Shihangli graphite deposit comprises a Pb isotope composition similar to that of the Madiyi Formation bulk rock and stibnite from the Xikuangshan Sb deposit.Based on the Re–Os,Sr,S,and Pb isotopic compositions of sul-fides in the graphite and Sb deposits in Central Hunan,the Madiyi Formation was likely the primary source of ore-forming elements(Sb,Au,and As).The Re–Os and Pb isotope compositions of pyrite most likely reflect when large-scale fluid migration and coal-generated graphite mineralization occurred in Central Hunan.
基金The authors acknowledge the University of Sharjah for financial support through a competitive research project grant(project number:23020406277)。
文摘As an alternative to lithium-ion batteries,aqueous zinc-graphite batteries(ZnGBs)are being explored as safer and low-cost options with the expectation of scalability to large energy storage systems.However,the currently adopted polyatomic and metal complex anion intercalation process at the graphite electrode in ZnGB exhibits poor electrochemical performances.Alternatively,incorporating halogen anions offers exceptional electrochemical performance to graphite electrodes due to their redox process.In this work,ZnGBs are assembled using a LiCl/ZnCl2/KBr^(-)based water-in-salt electrolyte,which efficiently supplies bromide(Br^(−))ions for conversion into Br_(x)^(−)and facilitates Br_(2)intercalation at the graphite electrode.The conversion and intercalation of bromine together enable the ZnGB to achieve a discharge capacity of 2.73 mAh/cm^(2)with 91.0%of coulombic efficiency(CE)while supporting high current density operations of up to 150 mA/cm^(2).With high energy density(4.56 Wh/cm^(2)),high power density(199.5 mW/cm^(2)),and excellent rate capability(∼93.0%CE at 150 mA/cm^(2)),the ZnGB is shown to operate efficiently for as much as 800 cycles.Beguilingly,an anode-free ZnGB offers enhanced stability for up to 1100 cycles without performance decay,matching the electrochemical performance of Zn metal electrodes.This work provides insights into the bromine reaction mechanism at graphite electrodes and the role of surface exfoliation in enabling efficient Br_(x)^(−)formation,along with Br_(2)intercalation,for achieving high-performance ZnGBs.
基金supported by European Union's Horizon Europe,UK Research and Innovation(UKRI).
文摘Graphite,encompassing both natural graphite and synthetic graphite,and graphene,have been extensively utilized and investigated as anode materials and additives in lithium-ion batteries(LIBs).In the pursuit of carbon neutrality,LIBs are expected to play a pivotal role in reducing CO_(2)emissions by decreasing reliance on fossil fuels and enabling the integration of renewable energy sources.Owing to their technological maturity and exceptional electrochemical performance,the global production of graphite and graphene for LIBs is projected to continue expanding.Over the past decades,numerous researchers have concentrated on reducing the material and energy input whilst optimising the electrochemical performance of graphite and graphene,through novel synthesis methods and various modifications at the laboratory scale.This review provides a comprehensive examination of the manufacturing methods,environmental impact,research progress,and challenges associated with graphite and graphene in LIBs from an industrial perspective,with a particular focus on the carbon footprint of production processes.Additionally,it considers emerging challenges and future development directions of graphite and graphene,offering significant insights for ongoing and future research in the field of green LIBs.
基金supported by the National Key Research and Development Program of China(2024YFA1612900)the National Natural Science Foundation of China(Grant No.52103365 and No.12375270)the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2021ZT09L227).
文摘Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.
基金Project(U19A2099)supported by the National Natural Science Foundation of China。
文摘In order to effectively prevent the contamination of carbon particle volatiles during high-purity SiC crystals are prepared using the physical vapor transport(PVT)method in ultra-high temperature environments(T³2000℃),this study innovatively attempts to protect graphite materials with SiC reinforced pyrolytic graphite(PyG)coating.It is discovered by preparing the SiC particle layer,the degree of graphitization and stability of PyG coating can be improved.The corrosion test results demonstrated that the SiC reinforced PyG coating can maintain an intact coating with a high graphitization degree after the SiC vapour corrosion test of 2050℃-120 h.Conversely,the samples with and without PyG coating reveal porous and eroded surfaces.Furthermore,following the SiC vapour corrosion test,the PyG coating sample’s integral ratio of D-band and G-band(I_(D)/I_(G))of Raman spectrum test data,reduced by 6.5%,while the SiC reinforced PyG coating decreased by 17.2%,indicating its excellent corrosion resistance.The application of SiC reinforced pyrolytic graphite coating in preparing the SiC single crystal might received a theoretical foundation according to this work.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2021M3H4A1A02048529)the Ministry of Trade,Industry and Energy(MOTIE)of the Korean government under grant No.RS-2022-00155854support from the DGIST Supercomputing and Big Data Center.
文摘To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.
基金funded by geological survey project of China Geological Survey(DD20211404)。
文摘Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation.
基金supported by the National Key Research and Development Program of China(No.2022YFC2403500)the National Natural Science Foundation of China(No.22225401)+1 种基金the Science and Technology Innovation Program of Hunan Province(No.2020RC4017)the Guizhou Provincial Science and Technology Projects(No.ZK[2023]293).
文摘Simultaneous identification and quantitative detection of phenylenediamine(PDA)isomers,including o-phenylenediamine(OPD),m-phenylenediamine(MPD),and p-phenylenediamine(PPD),are essential for environmental risk assessment and human health protection.However,current visual detection methods can only distinguish individual PDA isomers and failed to identify binary or ternary mixtures.Herein,a highly active and ultrastable peroxidase(POD)-like CoPt graphitic nanozyme was used for naked-eye identification and colorimetric/fluorescent(FL)dual-mode quantitative detection of PDA isomers.The CoPt@G nanozyme effectively catalyzed the oxidation of OPD,MPD,PPD,OPD+PPD,OPD+MPD,MPD+PPD and OPD+MPD+PPD into yellow,colorless,lilac,yellow,yellow,wine red and reddish-brown products,respectively,in the presence of H_(2)O_(2).Thus,the MPD,PPD,MPD+PPD and OPD+MPD+PPD were easily identified based on the distinct color of their oxidation products,and the OPD,OPD+PPD,OPD+MPD could be further identified by the additional addition of MPD or PPD.Subsequently,CoPt@G/H_(2)O_(2)-,a 3,3′,5,5′-tetramethylbenzidine(TMB)/CoPt@G/H_(2)O_(2)-,and MPD/CoPt@G/H_(2)O_(2)-enabled colorimetric/FL dual-mode platforms for the quantitative detection of OPD,MPD and PPD were proposed.The experimental results illustrated that the constructed sensing platforms exhibit satisfactory sensitivity,comparable to that reported in previous studies.Finally,the evaluation of PDAs in water samples was realized,yielding satisfactory recoveries.This work expanded the application prospects of nanozymes in assessing environmental risks and protection of human security.
基金supported by the National Natural Science Foundation of China(No.52274346).
文摘Waste graphitization cathode carbon blocks are a type of hazardous solid waste generated during the aluminum electrolysis process,and their proper disposal is a key step in the resource utilization of discarded graphite.This study utilizes the porous“defect advantage”of a cathode carbon block matrix to prepare silicon-doped and asphalt-coated detoxified and purified waste graphitization cathode carbon blocks for use as high-performance silicon/carbon composite anode materials.The results show that the uniformly silicondoped silicon/carbon composite material features a unique amorphous carbon-encapsulated“locked silicon”structure,which effectively addresses issues such as cathode volume expansion,excessive growth of the solid electrolyte interphase(SEI)film,and poor electrical contact between active materials.Consequently,electrochemical performance is enhanced.After assembly in a half-cell,the PSCC/10%Si@C(purified waste graphitization cathode carbon/10%Si@C)material exhibits optimal electrochemical stability,with an initial charging specific capacity of 514.5 mAh/g at 0.1 C(1 C=170 mA/g)and a capacity retention rate of 95.1%after 100 cycles.At a charge rate of 2.0 C,a specific capacity of 216.9 mAh/g is achieved.This technology provides a new pathway for the economical and high-value utilization of waste cathode carbon blocks and the development of low-cost,high-performance anode materials.
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.
基金This work was supported by Jimma Institute of Technology through Mega Project.
文摘The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Herein,for estimating the carbon content in graphite,the ASTM-C561,the test method for ash in a graphite sample,was used.For characterizing graphite,x-ray diffraction,x-ray fluorescence,inductively coupled plasma mass spectroscopy,and scanning electron microscopy were also used.Chemical analysis of ore samples determined that the average compositions are 63.35%SiO2,15.45%Al2O3,2.36%Fe2O3,2.07%K2O,less than1%others,and loss-on-ignition(LOI)in the range of^4.74%–37.42%.The total carbon content of graphitic ore ranged from 4.11%to 33.14%.Importantly,when graphite is concentrated through floatation,its average purity and recovery are 92.97%and 90.82%,respectively.Furthermore,once the graphite concentrates are treated with hydrofluoric acid,the average value attains a high grade of 96.48%C.Moreover,the average ash content is 81.93%(pre-flotation)and 3.1%(post-flotation),respectively.Finally,after beneficiation,a silica is identified as a major gangue(85.88%),usable as a raw material for other purposes such as cement.Hence,these graphite-bearing rocks seem to be worth exploring for commercialization opportunities.
文摘With the global rise of industries of the new-generation information technology, energy conservation and environmental protection, biotechnology, high-end manufacturing, new materials and clean-energy vehicles, traditional metal materials cannot meet the functional requirements. Consequently, ＂three rare mineral resources＂, regarded as the best altemative for current and future new industries, have received much attention among industrial circles and have become a new focus during the present geological prospecting in China.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022M3J7A1062940).
文摘With the growing demand for faster and more powerful computing,effective heat dissipation is essential to ensure the longevity,reliability,and high performance of electronic systems.In the field of modern electronic packaging materials,there is a great need for graphitic material-loaded polymeric composites(GPCs)with excellent thermal conductivities.However,the enhancement efficiency of GPCs is hindered by the agglomeration of fillers and the interfacial thermal resistance caused by the lack of continuous thermally conductive pathways between the filler and matrix.Understanding the interfaces between filler and matrix is of great importance in optimizing the performances of GPCs.Here,we fabricated graphite nanofibers(GNF)-loaded nanocomposites using acid-functionalized GNF(AGNF)and acidtetraethylenepentamine-functionalized(TGNF)as a filler and epoxy resin as a matrix with different GNF loading contents to explore the interfacial properties of the nanocomposites.The optimal GNF loading for AGNF was 0.5 wt.%,while the TGNF showed 0.75 wt.%.The highest thermal conductivity(0.51 W m^(−1) K^(−1))and fracture toughness(25.8 MPa m^(1/2))values were found in the TGNF-loaded nanocomposites with a fraction of 0.75 wt.%,representing enhancements of∼145%and∼400%,respectively,compared to those of neat nanocomposites.The experimental data presented herein demonstrate that the interfacial properties play a significant role in enhancing the thermal and mechanical performances of the nanocomposites.The present approach is expected to serve as a valuable tool in the design of conductive polymeric nanocomposites for further practical applications,such as thermal interface materials and packaging of high-power electric devices.
文摘Graphite is naturally floatable due to its hydrophobic pro pe rty and also soft and smears on other gangue particles, rendering the gangue mor e or less floatable too. Due to this reason it is important to concentrate on ar eas such as suitable flotation reagents, depression agents, pH modifiers, and pa rticle size to be fed during the process. The paper surveys and analyses the sui table particle size to be fed to achieve high-grade concentrate. According to t h e work carried out the author suggested the ideal cost effective flotation f low sheet for improved results at Bogala Mines in Sri Lanka.
基金supported by the National Natural Science Foundation of China(Nos.21271082 and 21371068)。
文摘In this paper,we introduced a novel method to prepare the few-layer nitrogen-doped graphene(FNG)from expandable graphite with melamine.The super-capacitive properties of FNG were thoroughly characterized by a three-electrode system,and the results showed the FNG electrode achieved a specific capacitance as high as 83.8 mF/cm2 together with excellent cycling stability.This method could be a novel approach to combine the pseudo-capacitors and electric double layer capacitors.
基金supported by the National Natural Science Foundation of China(No.51304027)China Postdoctoral Science Foundation(2014M560567 and 2015T80730)+4 种基金Shandong Province Science and Technology Development Plan(2014GSF120012)the State Key Program of Coal Joint Funds of National Natural Science Foundation of China(Nos.51134020 and U1261205)Shandong Province Natural Science Foundation(No.ZR2011EL036)the Doctoral Scientific Research Foundation of Binzhou University(No.2013Y06)the Key Technology Projects for Preventing Major Accident of National Security State Administration of Work Safety
文摘In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam(RPUF).The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in RPUF.However,excessive EG was capable of reducing the fluidity of polyurethane slurry.TEA exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then increased.DMMP had a remarkable effect on the flame retardant property and compressive strength of RPUF.Compressive strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in foam.DMMP displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of RPUF.Moreover,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_2.The oxygen index and flowing length of foam increased with the increase in isocyanate dosage.
文摘A novel nano-SnO2/graphite electrode has been prepared via polishing procedure to produce active and stable surface. The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbic acid into two well-defined peaks by 230 mV. The mechanism of discrimination of dopamine from ascorbic acid is discussed. Dopamine and ascorbic acid can be determined simultaneously with the modified electrode. The electrode shows good sensitivity, selectivity and stability.
基金supported by the National Natural Science Foundation of China(No.20335030)The Teaching and Research Award Program for 0utstanding Young Teachers in Higher Education Institutions of M0E ER,C.,the Natural Science Foundation of Gansu(No.3ZS051-A25-023)Key Laboratory of Ploymer Materials of Gansu Province
文摘A method for determination of epinephrine（EP） in the presence of ascorbic acid （AA） and dopamine （DA） with bare pyrolytic graphite electrodes has been described for the first time. In pH 7.0 phosphate buffer solution, the linear relationship was observed between the reduction peak current of EP and its concentration over the range from 1×10^-4 to 5×10^-7 mol/L, the related coefficient is 0.9992 （N=8）.
文摘The mineralogical features of the oxidation-reduction of graphite deposit in pingdu, Shandong province were studied by field search, polarization microscope, X-ray diffraction (XRD) and SEM. The results show that, the major rocks of the reduction graphite zone are graphite-quartz anorthosite, gabbro. The major rocks of the oxidation graphite zone are marble with graphite, biotite granite, monzogranite. The main minerals of the reduction zone are plagioclase, pyroxene, quartz, pyrite. The graphite is aphanitic graphite appearing as dense massive, layered, spherical aggregates. The main minerals of the oxidation zone are calcite, quartz, K-feldspar, biotite, amphibole, chlorite. The graphite is flake graphite uniformly dispersed in the loose, and strongly erosion rocks. A large number of rocks in the area have been suffered chloritization, regional metamorphism, indicating that the formation of the graphite deposit should be related with gabbro melting. The carbon source in the lower part was taken into the mine, and then experienced regional metamorphism.
