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Mass and chemical changes of immobile elements in Yamaghan Occurrence, Zanjan Province, Iran 被引量:1
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作者 I.Vosoughi Niri (Institute of Applied Geophysics, Central South University, Changsha 410083, P.R.China) 《中国有色金属学会会刊:英文版》 CSCD 2001年第4期617-622,共6页
Using mass and chemical changes, behavior of some elements have been evaluated in the study area, Yamaghan Occurrence. The techniques using immobile elements can precisely identify altered volcanic rock precursors and... Using mass and chemical changes, behavior of some elements have been evaluated in the study area, Yamaghan Occurrence. The techniques using immobile elements can precisely identify altered volcanic rock precursors and measure material changes. The rocks of the study area were affected by hydrothermal alteration. Testing of some compatible incompatible and compatible compatible immobile pairs indicates that Al 2O 3 is the most immobile component in the study area. It means that during the three main stages of hydrothermal alteration (phyllic, intermediate argillic and propylitic) aluminum was the most immobile and titanium was slightly immobile. Increases in mass mostly result from mineralization, silicification or carbonatization as voids and other open space fillings and may have replaced the part of glassy matrix. Mass addition has diluted the immobile elements at constant rates. Mass loss is commonly due to leaching of Si, Ca and Na 2O during chloritization and sericitization. The mass loss is recognized by increased proportions of inert minerals such as chlorite and sericite. Mineralographic studies in the study area shows the existence of a supergene zone. Calcocite and covellite are considered enriched minerals. Considering this evidence and mass change results, the enrichment of copper in the circulating fluid is suspected with occasional sulfide precipitation. 展开更多
关键词 mass and chemical changes immobile elements lithogeochemical Yamaghan
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Property changes of anchor grout calcined ginger nuts admixed with fly ash and quartz sand after accelerated ageing tests 被引量:2
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作者 ZHANG Jing-ke ZHANG Li-xiang +3 位作者 ZHAO Lin-yi LIU Dun GUO Qing-lin PEI Qiang-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第11期3114-3125,共12页
Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperatu... Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperature and humidity cycling test, soundness test and alkali resistance test are conducted with the objective to further research the property changes of CGN-(F+S) grout. Density, surface hardness, water penetration capacity, water permeability capacity, soluble salt, scanning electron microscopy (SEM) images and energy dispersive spectrometry (EDS) spectrum of these samples have been tested after accelerated ageing tests. The results show that densities of samples decrease, surface hardness, water penetration capacity and water permeability capacity of samples increase generally. Besides, soluble salt analysis, SEM and EDS results well corroborate the changes. Based on the results it can be concluded that property changes are most serious after temperature and humidity cycling test, followed by water stability, soundness and alkali resistance test in sequence. But in general, CGN-(F+S) still has good durability. 展开更多
关键词 CGN-(F+S) grout accelerated ageing tests physical property change chemical property change scanning electron microscopy energy dispersive spectrometry
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A new method for evaluating the injection effect of chemical flooding
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作者 Jian Hou Yan-Hui Zhang +2 位作者 Nu Lu Chuan-Jin Yao Guang-Lun Lei 《Petroleum Science》 SCIE CAS CSCD 2016年第3期496-506,共11页
Hall plot analysis,as a widespread injection evaluation method,however,often fails to achieve the desired result because of the inconspicuous change of the curve shape.Based on the cumulative injection volume,injectio... Hall plot analysis,as a widespread injection evaluation method,however,often fails to achieve the desired result because of the inconspicuous change of the curve shape.Based on the cumulative injection volume,injection rate,and the injection pressure,this paper establishes a new method using the ratio of the pressure to the injection rate(RPI) and the rate of change of the RPI to evaluate the injection efficiency of chemical flooding.The relationship between the RPI and the apparent resistance factor(apparent residual resistance factor) is obtained,similarly to the relationship between the rate of change of the RPI and the resistance factor.In order to estimate a thief zone in a reservoir,the influence of chemical crossflow on the rate of change of the RPI is analyzed.The new method has been applied successfully in the western part of the Gudong 7th reservoir.Compared with the Hall plot analysis,it is more accurate in real-time injection data interpretation and crossflow estimation.Specially,the rate of change of the RPI could be particularly suitably applied for new wells or converted wells lacking early water flooding history. 展开更多
关键词 Ratio of the pressure to the injection rate Rate of change of the RPI Injection efficiency chemical crossflow
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Structural evolution of carbon aerogel microspheres by thermal treatment for high–power supercapacitors 被引量:1
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作者 Feng Li Lijing Xie +5 位作者 Guohua Sun Fangyuan Su Qingqiang Kong Yufang Cao Xiangyun Guo Chengmeng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期439-446,共8页
In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. Th... In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. The effects of heat-treatment temperature(HTT) on the CAM microstructure were systematically investigated by physical and chemical characterization. The electrical conductivity increased by up to 250 S/cm and mesopores with high electrolyte accessibility developed in the CAM with increasing HTT. However, the specific surface area(SSA) decreased for HTTs from 1000 to 1600 ℃. The results show that these two factors should be finely balanced for further applications in high power supercapacitors.The CAMs carbonized at 1000 ℃ had the highest SSA(1454 m^2/g), large mesoporous content(20%) and favorable conductivity(71 S/cm). They delivered a high energy density of 38.4 Wh/kg at a power density of 0.17 kW/kg. They retained an energy density of 25.5 Wh/kg even at a high power density of 10.2 kW/kg,and a good rate capability of 84% after 10,000 cycles. This performance is superior to, or at least comparable to, those of most reported carbon materials. 展开更多
关键词 Carbon aerogel microspheres Heat-treatment temperature Physical/chemical changes CONDUCTIVITY SUPERCAPACITOR
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Characterization of Polymer Aging:A Review
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作者 Xuan Liu Rui Yang +5 位作者 Zhi-Ping Xu Yan Ye Guo-Shuo Tang Min Zhao Qian Zhang Xiang-Ze Meng 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第11期1642-1660,I0006,共20页
Polymer aging under environmental conditions causes deterioration of service properties.Understanding the aging behavior and mechanism is important not only for lifetime prediction,but also for material improvement an... Polymer aging under environmental conditions causes deterioration of service properties.Understanding the aging behavior and mechanism is important not only for lifetime prediction,but also for material improvement and development.Therefore,comprehensive characterization of polymer materials during aging is crucial.In this review,various analytical methods for characterization of chemical changes,physical changes and service properties are introduced.Based on that,methods for stabilization evaluation and lifetime prediction,especially sensitive evaluation methods are reviewed.Chemical changes include molecular weight changes by chain scission and crosslinking,functional group changes on the surface and in the bulk,formation of free radicals,formation of small molecular species as the degradation products,and chemical distribution by heterogeneous aging and additives migration.Physical changes include crystallization changes (post-or chemi-crystallization)and morphology changes (cracking,debonding,etc.).Service property changes include deterioration of processability,mechanical properties,electrical properties and appearance.In the end,existing problems and future research perspective are proposed,including relationship between chemical/physical changes and service properties,introduction of modern mathematical and computer tools. 展开更多
关键词 chemical change Physical change Service property Stability evaluation Lifetime prediction
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Different processing methods and pharmacological effects of Atractylodis Rhizoma
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作者 GUO Dongmei XU Kang +5 位作者 WAN Qianyun YU Songyang MA Chaoyang ZHANG Baohui LIU Yanju QU Linghang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第8期756-768,共13页
Atractylodis Rhizoma,a traditional Chinese medicine with an extensive history of treating gastrointestinal disorders and other diseases,undergoes various processing methods in China to enhance its therapeutic efficacy... Atractylodis Rhizoma,a traditional Chinese medicine with an extensive history of treating gastrointestinal disorders and other diseases,undergoes various processing methods in China to enhance its therapeutic efficacy for specific conditions.However,a comprehensive report detailing the changes in chemical composition and pharmacological effects due to these processing methods is currently lacking.This article provides a systematic review of the commonly employed processing techniques for Atractylodis Rhizoma,including raw Atractylodis Rhizoma(SCZ),bran-fried Atractylodis Rhizoma(FCZ),deep-fried Atractylodis Rhizoma(JCZ),and rice water-processed Atractylodis Rhizoma(MCZ).It examines the alterations in chemical constituents and pharmacological activities resulting from these processes and elucidates the mechanisms of action of the primary components in the various processed forms of Atractylodis Rhizoma in the treatment of gastrointestinal diseases. 展开更多
关键词 Atractylodis Rhizoma Processing method Pharmacological effect Change in chemical composition Gastrointestinal disease
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Particuology and climate change
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作者 Wen-Ching Yang 《Particuology》 SCIE EI CAS CSCD 2010年第6期507-513,共7页
The global concern over the greenhouse gas emissions and its effect on global warming and climate change has focused attention on the necessity of carbon dioxide capture and sequestration. There are many processes pro... The global concern over the greenhouse gas emissions and its effect on global warming and climate change has focused attention on the necessity of carbon dioxide capture and sequestration. There are many processes proposed to capture carbon either before or after combustion and these processes invariably involve investigation and application of traditional particuology. The solids employed are of different sizes, densities, morphologies, and strengths. Their handling, transportation, recirculation, and reactor applications are the essence of 'particuology'. Particuology can play an important and vital role in achieving cost-effective removal of carbon and minimize emissions of greenhouse gases. In this paper, the existing and developing carbon capture processes are briefly reviewed and the opportunities for application of particuology are identified. The review was not intended to be exhaustive. It is only in sufficient detail to make connection between particuology and climate change. For immediate and future challenges of reducing global warming and carbon capture and sequestration, innovative reactor design and application of parricuology is imperative. Expertise and innovation in particuology can greatly enhance the speed of development of those technologies and help to achieve cost-effective implementation. Particuology is indeed intimately related to the climate change and global warming. 展开更多
关键词 Particuology Fluidized beds Circulating fluidized beds Pre-combustion Post-combustion Oxycombustion chemical looping Carbon dioxide capture Carbon dioxide sequestration Climate changes Global warming
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