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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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Archival Examination of the Change in Packaging Materials of Chemical Injections
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作者 Lili YAN Weijun ZHOU +1 位作者 Peiyi CHEN Bo SHEN 《Medicinal Plant》 CAS 2023年第3期96-99,共4页
Based on the deepening awareness of the risk of changing packaging materials of injections,the national regulatory authorities and the China National Pharmaceutical Packaging Association have issued the relevant guide... Based on the deepening awareness of the risk of changing packaging materials of injections,the national regulatory authorities and the China National Pharmaceutical Packaging Association have issued the relevant guidelines and group standards for changing packaging materials in recent years,greatly improving the research and development and technical requirements of packaging materials of injections.In 2021,Guangdong Province carried out the archival examination of the change of listed drugs,among which the proportion of the acceptance of changed injection packaging materials has increased year by year.On the basis of sorting out the archival examination work and combining with the cases of changing packaging materials of chemical injections accepted by Guangdong Province during 2021-2022,the requirements and problems of archival examination were analyzed and discussed to provide a reference and idea for applicants when studying the change in packaging materials. 展开更多
关键词 chemical injection Change in packaging materials Archival examination Problem analysis Suggestions
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Effect of Processing and Cultivar on Thermo-Chemical Properties of Australian-Grown Hemp Hurd(Cannabis sativa L.)
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作者 Johannes Fehrmann Benoit Belleville +2 位作者 Barbara Ozarska Maya Ismayati Wahyu Dwianto 《Journal of Renewable Materials》 EI CAS 2024年第8期1475-1493,共19页
This study explored the thermo-chemical properties of industrial hemp hurd with different provenances,maturity stages,and retting protocols.The findings were then compared to hemp hurd used in the fabrication of citri... This study explored the thermo-chemical properties of industrial hemp hurd with different provenances,maturity stages,and retting protocols.The findings were then compared to hemp hurd used in the fabrication of citric acid-bonded ultra-low-density hemp hurd particleboard.Pyrolysis-gas chromatography-mass spectrometry(Py-GC/MS),Fourier-transform infrared spectroscopy(FTIR),and thermogravimetric analysis(TGA)were employed to document the variability of the hurd and comprehend the potential impact on biobased composite applications.The choice of cultivar,maturity stage,and processing modality significantly influenced the chemical composition,presence of functional groups,and thermal stability of the hurd.Py-GC/MS revealed substantial variations in the lignin-to-carbohydrate(L/C)ratio,along with the absence of fatty acids in certain cultivars.While FTIR signals confirmed consistent functional groups,differences in peak intensities were indicative of carbohydrate variations associated with maturity and retting duration,impacting the availability of hydroxyl groups for,i.e.,interparticle bonding in citric acid-based bio-composites.Furthermore,it was observed that shorter retting durations initially enhanced the thermal resistance,but prolonged retting led to accelerated degradation,significantly reducing the hurd’s residual mass.The findings indicated notable differences among the samples,emphasizing the importance of investigating variables such as provenance/cultivar,maturity,and processing modality.This assessment is essential to ensure effective agronomic practices that align the raw material characteristics with the specific requirements of intended applications,such as the fabrication of biobased hemp hurd composites. 展开更多
关键词 Hemp hurd material characterization chemical analysis thermal analysis
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CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier
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作者 Benjamin Fleiß Juraj Priscak +3 位作者 Martin Hammerschmid Josef Fuchs Stefan Müller Hermann Hofbauer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期296-310,共15页
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ... Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology. 展开更多
关键词 chemical looping combustion BECCS Techno-economic assessment CO_(2)capture costs Oxygen carrier development Synthetic materials ILMENITE
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Chemicals Used in Polymeric Material Coated Waste Paper Composites
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作者 Zübeyde Bülbül Birol Üner 《Journal of Materials Science and Chemical Engineering》 2023年第5期1-10,共10页
In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), ... In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), Titanate and Silanyl (Vinyltriethoxysilane) were added waste paper. Composite boards were pressed and cut in 1 × 30 × 30 cm. In order to identify some properties of the produced boards, experimental works were applied according to the standards. In conclusion, bending stress reduced with filler materials and chemicals was reduced even more than the bending stress except for some experimental groups. In addition, it was observed that the coupling chemicals increased the bending strength and modulus of elasticity compared to the fillers. 展开更多
关键词 Matching chemicals Paper Composites Filling materials POLYMERS Coupling Agents Paper Fibers
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Solution-based Chemical Strategies to Purposely Control the Microstructure of Functional Materials 被引量:4
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作者 Fei LIU Congting SUN Chenglin YAN Dongfeng XUE 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期641-648,共8页
Micro/nanostructured crystals with controlled architectures are desirable for many applications in optics, electronics, biology, medicine, and energy conversions. Low-temperature, aqueous chemical routes have been wid... Micro/nanostructured crystals with controlled architectures are desirable for many applications in optics, electronics, biology, medicine, and energy conversions. Low-temperature, aqueous chemical routes have been widely investigated for the synthesis of particles, and arrays of oriented nanorods and nanotubes. In this paper, based on the ideal crystal shapes predicted by the chemical bonding theory, we have developed some potential chemical strategies to tune the microstructure of functional materials, ZnS and Nb205 nanotube arrays, MgO wiskers and nestlike spheres, and cubic phase Cu2O microcrystals were synthesized here to elucidate these strategies. We describe their controlled crystallization processes and illustrate the detailed key factors controlling their growth by examining various reaction parameters. Current results demonstrate that our designed chemical strategies for tuning microstructure of functional materials are applicable to several technologically important materials, and therefore may be used as a versatile and effective route to the controllable synthesis of other inorganic functional materials. 展开更多
关键词 Functional materials chemical strategy chemical bonding theory MICROSTRUCTURE
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Synthesis of steel slag ceramics: chemical composition and crystalline phases of raw materials 被引量:3
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作者 Li-hua Zhao Wei Wei +2 位作者 Hao Bai Xu Zhang Da-qiang Cang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第3期325-333,共9页
Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.... Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.84 MPa, respectively, were obtained. The presence of anorthite, a-quartz, magnetite, and pyroxene crystals (augite and diopside) in the steel slag ceramics were very different from the composition of traditional ceramics. X-ray diffraction (XRD) and electron probe X-ray microanalysis (EPMA) results illustrated that the addition of steel slag reduced the temperature of extensive liquid generation and further decreased the firing temperature. The considerable contents of glass-modifying oxide liquids with rather low viscosities at high temperature in the steel slag ceramic adobes promoted element diffusion and crystallization. The results of this study demonstrated a new approach for extensive and effective recycling of steel slag. 展开更多
关键词 ceramic materials SYNTHESIS steel slag chemical composition crystalline phases solid waste recycling
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Use of Several Plant Materials and Chemicals to inhibit Soil Urease Activity and Increase Nitrogen Recovery Rate of Urea by Plant 被引量:6
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作者 XU WEIHONG, WANG ZHENGYIN, JIA ZHONGYUAN, HUANG YUN, YUAN LUJIANG and WANG JUANMEICollege of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第3期275-282,共8页
Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Li... Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Linn.) O. Ktze. f., P_4), oleander (Nerium indicum Mill,P_5), rape (Brassica campestris L., P_g), Chinese tallow tree (Sapium sebiferum L., P_7), tung(Vernicia fordii (Hemsl.), P_8), and croton (Croton tiglium L., P_9), 7 chemicals, boric acid (C_1),borax (C_2), oxalic acid (C_3), sodium oxalite (C_4), sodium dihydrogen phosphate (C_6), sodiumsilicate (C_7) and sodium citrate (C_8), and a natural organic substance, humic acid (C_5), onurease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied throughincubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. Afterincubation at 37℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity wereselected and then incubated for 14 days at 25℃. Results of the incubation experiments showed thatsoil urease activity was greatly inhibited by them, and the inhibition effect followed an order ofP_2>P_4>C_3>C_2>P_3>C_1>HQ>P_1. The 7 selected materials reduced the accumulative amounts of Nreleased from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively,and postponed the N release peak by 2~4 days in the incubation period of 14 days under constanttemperature, as compared to the control (no inhibitor). In the pot experiment with the 7 materialsat two levels of addition, low (L) and high (H), the C_1 (H), C_3 (H), C_1 (L), P_4 (L) and C_2 (L)treatments could significantly increase the dry weights of the aboveground parts and the totalbiomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% ascompared to the control (no hibitor). 展开更多
关键词 chemicalS plant materials recovery rate of fertilizer nitrogen ureaseactivity
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Development and Application of Hydrocracking Catalysts RHC-1/RHC-5 for Maximizing High Quality Chemical Raw Materials Yield 被引量:6
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作者 Mao Yichao Nie Hong +3 位作者 Li Mingfeng Hu Zhihai Zhao Guangle Zhao Yang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第2期41-47,共7页
To adapt to the change in the demand of the oil refining market,two hydrocracking catalysts,RHC-1 and RHC-5,were developed to improve the quality of tail oil.The catalysts were designed based on the theory of selectiv... To adapt to the change in the demand of the oil refining market,two hydrocracking catalysts,RHC-1 and RHC-5,were developed to improve the quality of tail oil.The catalysts were designed based on the theory of selective ring-opening.By selecting more acidic molecular sieves,the problem of poor selectivity of conventional materials can be solved to properly match up to the hydrogenation performance of catalysts.Compared with the performance of previous catalysts,the quality of the tail oil achieved by the said catalysts is better,and the BMCI is reduced by 1—2 units.In the long cycle operation of the petroleum industry,the good quality of the tail oil has been verified and the adaptability of the process conditions is good.When the RHC-1 catalyst is used to process heavy feed under medium pressure,a BMCI value of about12 can be obtained along with a nearly 60%yield of tail oil.The total yield of chemical raw material(steaming cracking feed+catalytic reforming feed)can exceed 80%,and the hydrogen consumption has dropped by nearly 50%as compared to the conventional hydrocracking conversion rate.When processing a mixed CGO and VGO feed with the full conversion mode under a hydrogen pressure of 13.0 MPa,the RHC-5 catalyst can yield about 68.4%of heavy naphtha with a potential aromatic content of up to 50.6,while the total yield of chemical raw materials can reach more than 98%.The results of industrial application of these catalysts show that more than 30%of high quality tail oil can be obtained via processing of inferior quality feed,and its BMCI value can reach 10.7.The total yield of chemical raw materials can reach more than65%.The industrial operation process has implemented two operating cycles totaling 8 years. 展开更多
关键词 HYDROCRACKING CATALYST chemical raw material tail oil
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A review on novel activation strategy on carbonaceous materials with special morphology/texture for electrochemical storage 被引量:3
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作者 Yueming Li Ziyan Pu +1 位作者 Qimeng Sun Ning Pan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期572-590,共19页
Various novel carbonaceous materials including carbon nanotubes,nano-onions,carbon microspheres,graphene nanosheets,and carbon microfibers with unique properties,such as tunable surface area and pore size,high chemica... Various novel carbonaceous materials including carbon nanotubes,nano-onions,carbon microspheres,graphene nanosheets,and carbon microfibers with unique properties,such as tunable surface area and pore size,high chemical stability,cost-effective and facile preparation,have attracted enormous interest for many applications.Also essential,the activation processes play a critical role to achieve these valuable properties.In this review,we provide a thorough analysis of the emerging nano-and microscopic carbon species with special morphology/textures and currently available types of chemical activation agents,and novel activation strategy to enhance electrochemical performance of activated carbon material in electrical energy storage devices including supercapacitor and alkaline ions batteries.A particular emphasis is set on recent advance in activated carbon materials with special morphology/textures for supercapacitors and sodium ion batteries. 展开更多
关键词 Carbonaceous materials Special morphology/texture chemical activation DOPING SUPERCAPACITOR Rechargeable batteries Sodium ion batteries
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Intercalation Assembly and Chemical Product Engineering of Layered Intercalated Functional Materials Based on Efficient Utilization of Magnesium Resources in Salt Lakes
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作者 LIN Yanjun NING Bo +1 位作者 LI Kaitao WU Qin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期347-349,共3页
1 Introduction Magnesium salts are very important by-product of salt lake industry in West China.Nearly 200 million cubic meters of waste brine are released to the environment
关键词 layered intercalated functional materials Intercalation assembly chemical product engineering magnesium resources salt lakes
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Chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery
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作者 闫时建 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第6期863-866,共4页
A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, an... A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents. 展开更多
关键词 chemical extraction delithiated cathode material Li-ion battery
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Geotechnical,Mineralogical and Chemical Characterization of the Missole II Clayey Materials of Douala Sub-Basin(Cameroon)for Construction Materials 被引量:1
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作者 Elisabeth Olivia Logmo Gilbert Francois Ngon Ngon +2 位作者 Williams Samba Michel Bertrand Mbog Jacques Etame 《Open Journal of Civil Engineering》 2013年第2期46-53,共8页
Geotechnical tests conducted on clayey materials of Missole II, Douala sub-basin of Cameroon showed that these materials present: fines particles (55 to 78 wt.%), sand (22 to 44 wt.%), and plasticity index of 13.8 to ... Geotechnical tests conducted on clayey materials of Missole II, Douala sub-basin of Cameroon showed that these materials present: fines particles (55 to 78 wt.%), sand (22 to 44 wt.%), and plasticity index of 13.8 to 21.6%. The X-ray diffraction (XRD) and the chemical analysis revealed a kaolinite amount of 46 to 56 wt.%, 19 to 27 wt.% of illite, 12 to 19 wt.% of quartz, 3 to 5 wt.% of goethite, 2 to 5 wt.% of hematite, 1.5 to 5 wt.% of anatase, 2 to 3 wt.% of feldspar-K with 52.87 to 63.11 wt.% of SiO2, 18.08 to 24.31 wt.% of Al2O3, 3.28 to 11.45 wt.% of Fe2O3 and a small content of bases (<2 wt.%). The results of geotechnical tests combined to those of the XRD and the chemical analysis showed that the Missole II clayey materials are suitable for the manufacture of bricks, tiles and sandstones. 展开更多
关键词 Cameroon Construction materials Geotechnical Tests Mineralogical and chemical Analyses Missole II
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The research on nano materials and its application in the chemical aspects
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《International English Education Research》 2013年第12期50-52,共3页
The nanotechnology is of great siguifieance to the country's future economic, social development and national security, and it will bring a revolutionary change to the medicine, manufacturing, materials and informati... The nanotechnology is of great siguifieance to the country's future economic, social development and national security, and it will bring a revolutionary change to the medicine, manufacturing, materials and information communication and other industries, therefore, in recent years, nano science and technology is greatly favored all over the world especially in developed countries. All the countries (areas) in the world have developed the nanotechnology as the main driver of the technical innovation in the twenty-first century, and have formulated development strategies and plans, to promote and guide their development in nanotechnology, which lead to fiercer and fiercer competition. In this paper, the author mainly introduces the application of nano materials in catalysis, filtration, separation, paint and new fine chemical industry and so on. 展开更多
关键词 Nano materials chemical production CATALYSIS STRUCTURE
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Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials——Gravimetric method for determination of loss on ignition
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作者 WANG Jing 《China's Refractories》 CAS 2006年第4期39-40,共2页
1 Scope This standard specifies the gravimetric method for determination of loss on ignition.
关键词 Gravimetric method for determination of loss on ignition chemical Analysis of Magnesia and Magnesia-Alumina Refractory materials
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A New Type of Multielements-Doped,Carbon-based Materials Characterized by High-thermoconductiv-ity,Low Chemical Sputtering,Low RES Yield and Exposure to Plasma
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作者 许增裕 刘翔 +4 位作者 谌继明 王明旭 宋进仁 翟更太 李承新 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第3期1311-1317,共7页
Low-Z materials, such as carbon-based materials and Be, are major plasma-facing material (PFM) for current, even in future fusion devices. In this paper, a new type of multielement-doped carbon-based materials develop... Low-Z materials, such as carbon-based materials and Be, are major plasma-facing material (PFM) for current, even in future fusion devices. In this paper, a new type of multielement-doped carbon-based materials developed are presented along with experimental re-sults of their properties. The results indicate a decrease in chemical sputtering yield by one order of magnitude, a decrease in both thermal shock resistance and radiation-enhanced sublimation, an evidently lower temperature desorption spectrum, and combined properties of exposing to plasma. 展开更多
关键词 than GBS RES A New Type of Multielements-Doped Carbon-based materials Characterized by High-thermoconductiv-ity Low chemical Sputtering Low RES Yield and Exposure to Plasma
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Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials——Flame atomic absorption spectrometric method for determination of calcium oxide content
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作者 ZHANG Xiaohui 《China's Refractories》 CAS 2006年第4期41-43,共3页
1 Scope This standard specifics the determination of calcium oxide coutent by flame atomic absorption spectrometric method.
关键词 chemical Analysis of Magnesia and Magnesia-Alumina Refractory materials Flame atomic absorption spectrometric method for determination of calcium oxide content
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Mineralogical, Geochemical and Physico-Chemical Characterization of Clay Raw Materials from Three Clay Deposits in Northern Cameroon
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作者 B. P. Kagonbé D. Tsozué +1 位作者 A. N. Nzeukou S. Ngos III 《Journal of Geoscience and Environment Protection》 2021年第6期86-99,共14页
The characterization of clay raw materials of three clay deposits from Northern Cameroon was investigated. The three deposits, located in Gaschiga, Sekandé and Boulgou, are locally used as building materials, but... The characterization of clay raw materials of three clay deposits from Northern Cameroon was investigated. The three deposits, located in Gaschiga, Sekandé and Boulgou, are locally used as building materials, but no data are available on these materials and they are relatively unknown. Mineralogical, geochemical and physico-chemical characteristics were studied, using X-ray diffraction, X-ray fluorescence and physico-chemical analyses. Mineralogically, quartz was the most abundant mineral in the studied raw materials. It is associated to abundant quantity of smectite, kaolinite and K-feldspars, and slightly abundant to traces of hematite and amphibole. Geochemically, those clayey soils are more siliceous (SiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">, 51% - 59%) with significant amount of aluminum (Al</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, 15% - 19%) followed by iron oxides (Fe</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, 3% - 10%). Other oxides (K</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O, MgO, TiO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">, Na</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O, MnO, CaO and P</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">5</span></sub><span style="font-family:Verdana;">) are in relatively lower proportion. High level of silica content explains the sandy nature of these clays. The results of granulometric analysis show that the studied raw material contain sand (39% - 68%) as major grain size followed by clay particles (17% - 38%), silt (1% - 36%) and gravels (0% - 16%). The studied clayey soils were moderately plastic, with plasticity index values ranging from 13% to 30%, and are also characterized by very high liquidity limits of 34% - 63%. 展开更多
关键词 Clay material Characterization MINERALOGICAL PHYSICO-chemical North-Cameroon
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Preparation of Anode Material for Lithium Ion Battery by Chemical Oxidation 被引量:1
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作者 Yu Ping WU Chun Rong WAN +2 位作者 Chang Yin JIANG Jian Jun LI Yang Xing LI(Institute of Nuclear Energy Technology. Tsinghua University, Beijing 102201) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第4期339-340,共2页
Anode material for lithium ion battery is prepared by chemical oxidation of natural graphite. After oxidation, the properties of natural graphite are modified, such as surface structure, the content of graphite phases... Anode material for lithium ion battery is prepared by chemical oxidation of natural graphite. After oxidation, the properties of natural graphite are modified, such as surface structure, the content of graphite phases, the number of micropores and its stability. thus the modified natural graphite can be used as anode material for commercial lithium ion battery. The reversible capacity is increased from 100 mAh/g to above 300 mAh/g, and its cycling properly is also satisfactory. 展开更多
关键词 anode material PREPARATION chemical oxidation lithium ion battery
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Characterization of Calcined Kaolin/TiO_2 Composite Particle Material Prepared by Mechano-Chemical Method 被引量:3
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作者 王柏昆 丁浩 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第5期765-769,共5页
Calcined kaolin/TiO2 composite particle material (CK/TCPM) was prepared with TiO2 coating on the surfaces of calcined kaolin particles by the mechano-chemical method. X-ray diffraction (XRD) and scanning electron ... Calcined kaolin/TiO2 composite particle material (CK/TCPM) was prepared with TiO2 coating on the surfaces of calcined kaolin particles by the mechano-chemical method. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to investigate the microstructures and morphologies, respectively. The mechanism of the mechano-chemical reaction between calcined kaolin and TiO2 was studied by infrared spectra (IR). The results show that TiO2 coats evenly on the surfaces of calcined kaolin particles by Si-O-Ti and Al-O-Ti bonds on their interfaces. The hiding power and whiteness of CK/TCPM are 17.12 g/m^2 and 95.7%, respectively, presenting its similarity to TiO2 in pigment properties. 展开更多
关键词 mechano-chemical method calcined kaolin TIO2 composite particles material pigment properties
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