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中国最早的分析化学译著——《化学分原》 被引量:1
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作者 吴又进 柯资能 《广西民族大学学报(自然科学版)》 CAS 2009年第3期27-31,37,共6页
《化学分原》是当时西方最流行的实用化学工艺分析教材的中译本,首次将西方近代分析化学知识介绍到中国,标志着近代分析化学的正式传入,其分析化学实验知识和科学仪器的介绍,为中国传统化学走向实验化学奠定了基础.
关键词 《化学分原》 化学 化学 傅兰雅 徐建寅
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晚清-民国化学书籍中化学名词术语的比较分析——以《化学分原》中化学名词术语的演变为例
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作者 吴又进 柯资能 《广西民族大学学报(自然科学版)》 CAS 2014年第1期16-20,36,共6页
《化学分原》是传入中国的第一本分析化学译著,其中的一些化学名词术语与现今译名已具有相似的或甚至完全相同的表述形式.通过对《化学分原》英文底本、中译本、化学语汇、现今化学名词词典中化学名词术语的比较分析,研究了这些化学名... 《化学分原》是传入中国的第一本分析化学译著,其中的一些化学名词术语与现今译名已具有相似的或甚至完全相同的表述形式.通过对《化学分原》英文底本、中译本、化学语汇、现今化学名词词典中化学名词术语的比较分析,研究了这些化学名词术语在这一时期的演变规律.有一些化学名词术语沿用了当时的原始译法,但化学名词术语的确定主要参考和借鉴了19世纪末20世纪初日文中的汉字译名. 展开更多
关键词 《化学分原》 化学名词术语 傅兰雅 徐建寅
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The Chemical Constituents from the Bulbs of Ornithogalum caudatum 被引量:12
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作者 唐于平 俞飚 +2 位作者 胡杰 吴弢 惠永正 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期169-171,共3页
A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonade... A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonadecyl alcohol(2), eicosanol(3), behenic acid(4), b-sitosterol(5), stigmasterol(6), glycerol 1-monocerotate(7), pyrocatechol(8), p-ethoxybenzoic acid(9), p-coumarinic acid(10), protocatechuric acid(11), ursolic acid(12), betulinic acid(13), fumaric acid(14), succinic acid(15), uracil(16), xanthine(17), quercetin(18), kaempferol (19), isorham-netin(20), adenosine(21), daucosterol(22), stigmasterol 3-O-b-D-glucopyranoside(23), quercetin 3-O-b-D-glucopyra-noside(24), kaempferol 3-O-b-D-glucopyranoside(25), rutin(26), and kaempferol 3-O-b-rutinoside(27). All of them, except compound 5, were isolated from this plant for the first time. 展开更多
关键词 Ornithogalum caudatum BULB Chemical constituent
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Preparation of nanostructure silver powders by mechanical decomposing and mechanochemical reduction of silver oxide 被引量:3
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作者 Gholam Reza KHAYATI Kamal JANGHORBAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1520-1524,共5页
The mechanical decomposing and mechanochemical reductions of silver oxide for preparation of nanocrystalline silver powders by high planetary ball mill was investigated. XRD and HRSEM techniques were used to character... The mechanical decomposing and mechanochemical reductions of silver oxide for preparation of nanocrystalline silver powders by high planetary ball mill was investigated. XRD and HRSEM techniques were used to characterize the structural evolution and morphological changes of products. The results show that the nanostructured silver with an average crystallite size of 14 nm and internal strain of 0.75% is synthesized by mechanical decomposing of Ag2O after 95 h milling. While, the product of mechanochemical reduction of silver oxide using graphite after 22 h milling is nanostructured silver with an average crystallite size of 28 nm and internal strain of 0.44%. 展开更多
关键词 nanocrystalline silver silver oxide mechanical decomposing mechanochemical reduction
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Design Criterion for Fixture Layout Based on the State Space Model in M ultistation Assembly Processes 被引量:2
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作者 张磊 周一帆 +1 位作者 张志胜 史金飞 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期175-181,共7页
The fixture layout is crucial to assure the product quality in a multistation assembly process (MAP). A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation... The fixture layout is crucial to assure the product quality in a multistation assembly process (MAP). A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation inputs. As the basis of the fixture layout design, the design criterion plays an important role in the effectiveness of a solution and the optimization efficiency. In this paper, an effective and efficient design criterion is proposed for the fixture layout with a fixed reference point (FRP) in an MAP. First of all, a state space model for the individual port's variation propagation and accumulation is developed, which is the mathematical foundation of the proposed criterion. Then, based on this model, a novel design criterion used to evaluate the performance of the fixture layout is proposed for the fixture layout with an FRP. Finally, a method extracted from the proposed design criterion is developed for quick fixture layout design. A four-station assembly process is used to validate the effectiveness and efficiency of the proposed models and methods. 展开更多
关键词 state space model covariance matrix fixed reference point (FRP) largest distance
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Knowledge-Based Classification in Automated Soil Mapping 被引量:10
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作者 ZHOU BIN and WANG RENCHAOInstitute of Agricultural Remote Sensing and Information Technology Application, Zhejiang University, Hangzhou 310029 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第3期209-218,共10页
A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowle... A machine-learning approach was developed for automated building of knowledgebases for soil resources mapping by using a classification tree to generate knowledge from trainingdata. With this method, building a knowledge base for automated soil mapping was easier than usingthe conventional knowledge acquisition approach. The knowledge base built by classification tree wasused by the knowledge classifier to perform the soil type classification of Longyou County,Zhejiang Province, China using Landsat TM bi-temporal images and CIS data. To evaluate theperformance of the resultant knowledge bases, the classification results were compared to existingsoil map based on a field survey. The accuracy assessment and analysis of the resultant soil mapssuggested that the knowledge bases built by the machine-learning method was of good quality formapping distribution model of soil classes over the study area. 展开更多
关键词 CLASSIFICATION classification tree KNOWLEDGE-BASED rule extracting soilmapping
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Review and Comprehensive Analysis of Composition and Origin of High Acidity Crude Oils 被引量:1
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作者 Cai Xinheng Tian Songbai (Research Institute of Petroleum Processing,SINOPEC,Beijing 100083,China) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第1期6-15,共10页
High acidity crude oils have an advantage over normal oils in terms of their price,but can cause corrosion and refinery problems.They are the so-called opportunity crudes and likely to be important reserved resources ... High acidity crude oils have an advantage over normal oils in terms of their price,but can cause corrosion and refinery problems.They are the so-called opportunity crudes and likely to be important reserved resources in the 21st century.Researches on high acidity crude oils are becoming more and more profound.Based on the existing research achievements,this article has given an overview of the chemical composition and acid distribution of high acidity oils,and also analyzed their origin types and potential influence factors. 展开更多
关键词 high acidity oils total acid number acid composition ORIGIN influence factors
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Single atom‐based catalysts for electrochemical CO_(2) reduction 被引量:3
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作者 Qian Sun Chen Jia +1 位作者 Yong Zhao Chuan Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1547-1597,共51页
Electrochemical CO_(2) reduction reaction(CO_(2)RR),powered by renewable energy,emerges as a promising approach against environmental issues and energy crisis by converting CO_(2) into val‐ue‐added chemicals.Single ... Electrochemical CO_(2) reduction reaction(CO_(2)RR),powered by renewable energy,emerges as a promising approach against environmental issues and energy crisis by converting CO_(2) into val‐ue‐added chemicals.Single atom catalysts(SACs)with isolated metal atoms dispersed on supports exhibit outstanding performance for CO_(2) electroreduction,because of their strong single at‐om‐support interactions,maximum metal utilization and excellent catalytic activity.However,SACs suffer from agglomeration of particles,low metal loading,and difficulty in large‐scale production.In addition,molecular catalysts as another single atom‐based catalyst,consisting of ligands molecules connected to metal ions,exhibited similar metal‐nitrogen(M‐N)active centers as that in met‐al‐nitrogen‐carbon(M‐N‐C)SACs,which were highly active to CO_(2) reduction due to their well‐defined active sites and tunability over the steric and electronic properties of the active sites.Nonetheless,molecular catalysts are challenged by generally moderate activity,selectivity and sta‐bility,poor conductivity and aggregation.Many works have been devoted to overcoming these is‐sues of SACs and molecular catalysts for efficient CO_(2)RR,but only limited reviews for systematic summary of their fabrication,application,and characterizations,which were highlighted in this review.Firstly,we summarize recent advanced strategies in preparing SACs for CO_(2)RR,including wet‐chemistry approaches(defect engineering,spatial confinement,and coordination design),other synthetic methods and large‐scale production of SACs.Besides,electrochemical applications of SACs and molecular catalysts on CO_(2)RR are discussed,which involved the faradaic efficiency and partial current density of the desired product as well as the catalyst stability.In addition,ex‐situ and in‐situ/operando characterization techniques are briefly assessed,benefiting probing the active sites and understanding the CO_(2)RR catalytic mechanisms.Finally,future directions for the devel‐opment of single atom‐based catalysts(SACs,molecular catalysts)are pointed out. 展开更多
关键词 CO_(2)electroreduction Wet‐chemistry approach Single atom catalyst Molecular catalyst In-situ characterization
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Textural and Geochemical Characteristics of Proglacial Sediments: A Case Study in the Foreland of the Nelson Ice Cap, Antarctica 被引量:8
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作者 LIUXiaodong SUNLiguang YINXuebin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第4期970-981,共12页
This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sedim... This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sediments are characteristic of glacigenic deposits, but very different from those of aeolian and lacustrine sediments. Moreover, the grain size distributions of the proglacial sediments are fractal with a dimension of about 2.9, and the fractal dimensions can be used as another summary statistical parameter for quantifying the relative amounts of coarse and fine materials. Correlations between the absolute element abundances of the proglacial sediments are very weak due to mineral partitioning and other effects of glacial processes, but correlations between the element/Rb ratios are statistically significant. This finding indicates that element/Rb ratios can be used to reduce or eliminate the effects of glacial processes, evaluate geochemical data and determine the sediment provenance in the foreland of Antarctic glacier. Comparisons on the element concentrations among different environments suggest that the proglacial sediments are derived predominantly from local bedrocks and appear to be natural in origin. Thus these natural sediments can be used to study chemical weathering in the proglacial foreland of modern glacier. 展开更多
关键词 proglacial sediment grain size fractal dimension element abundance chemical weathering
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Preparation of Chitosan-g-PAM PS in H_2O/scCO_2 Inverse Emulsion
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作者 王晶 孙扶 +2 位作者 仲建峰 方舟 董擎之 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期169-174,共6页
Chitosan (CS) was successfully modified in supercritical carbon dioxide ( scCOz ) by grafting method to enhance its water solubility. In this work, a three.arm star-like fluorinated polymer was synthesized by atom... Chitosan (CS) was successfully modified in supercritical carbon dioxide ( scCOz ) by grafting method to enhance its water solubility. In this work, a three.arm star-like fluorinated polymer was synthesized by atom transfer radical polymerization ( ATRP ) method and applied as a surfactant in supereriticul carbon dioxide (scCO2 ). Then 2-acrylamido-2-methyl propane sulfonie acid (AMPS) was grafted onto CS (CS-g-PAMPS) in H2O/scCO2 inverse emulsion. The effects of mass ratio of water and surfactants (Rw/s ) and pressure of scCO2 on the grafting reaction were investigated. The grafting rate, partide size, and dispersity in water of CS-g-PAMPS varied greatly as Rw/s and pressure of scCO2 changed. It could be found that the value of Rw/s at 12 and the pressure of scCO2 at 30 MPa were the optimum conditions for the grafting reaction. CS-g-PAMPS prepared in this reaction system has higher grafting rate, smaller particle sizes, and better dispersity in water than those prepared via conventional methods. 展开更多
关键词 atom transfer radical polymerization (ATRP) graft copolymer inverse emulsion polymerization supercritical carbon dioxide scCO2 SURFACTANT
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Synthesis and Characterization of Poly [2,2-( m-phenylene) -5,5-bibenzimidazole] in 1-butyl-3-methylimidazolium Chloride
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作者 白雪君 王彪 +3 位作者 唐艳芳 文志伟 江建明 王华平 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期239-243,共5页
Poly[ 2, 2-(m.phenylene) -5, 5-bibenzimidazole] (mPBI) were synthesized by mixing 3, 3', 4, 4'-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride ( E BMIM] CI). Intrinsic viscosit... Poly[ 2, 2-(m.phenylene) -5, 5-bibenzimidazole] (mPBI) were synthesized by mixing 3, 3', 4, 4'-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride ( E BMIM] CI). Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96% sulfuric acid. The polymer was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance ( 1H-NMR ), and thermogravimetric analysis (TGA). The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated. It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature. Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs) and polyphosphoric acid was also reported. It indicates that the ionic liquids are a kind of good solvents in synthesis process of m_PBI and ionic liquids mainly affect molecular weight of mPBL 展开更多
关键词 polybenzimidazole PBI 1-butyl-3-methylimidazolium chloride( [ BMIM] C1 ionic liquids(ILs) synthesis
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Hydrogen Adsorption on Pt, Rh and Pt-Rh Electrodes 被引量:2
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作者 贾梦秋 A.M.Meretskyi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期102-106,共5页
The hydrogen adsorption on Pt-Rh alloys in sulfuric acid aqueous solutions was studied by the method of cathode pulses. Hydrogen adsorption on the electrode with all ratio of alloy components (ωRh = 0-100%) is well d... The hydrogen adsorption on Pt-Rh alloys in sulfuric acid aqueous solutions was studied by the method of cathode pulses. Hydrogen adsorption on the electrode with all ratio of alloy components (ωRh = 0-100%) is well described by the Temkin logarithmic isotherm. The surface coverage by adsorbed hydrogen at the same potential is decreased with increasing content of rhodium in the system. A linear dependence of adsorption peak potential on the alloy compositions in the case of weakly bonded adsorbed hydrogen is established. Hydrogen adsorption heat as a function of surface coverage for Pt-Rh-electrodes was obtained. The shape of the current-potential curve and position of the weakly bonded hydrogen adsorption on the potential scale are all related to alloy compositions, thus can serve as the basis for the determination surface composition of alloys. 展开更多
关键词 hydrogen adsorption potentiodynamic pulses platinum-rhodium alloys
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Some Problems of Irrigation Water Management in Lower Cheliff Plain (Algeria) 被引量:1
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作者 Abdelhamid BradaI Abdelkader Douaoui Tarik Hartani 《Journal of Environmental Science and Engineering(A)》 2012年第3期271-278,共8页
In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the... In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the balance between supply and demand. The two surface water resources, Gargar and Merdjet Sidi Abed dams, do not satisfy the requirements of agriculture water. According to the National Office of the Irrigation and Drainage data, the quantity of allocated water is never distributed; the difference between allocated water and drop water can also exceed 20%, and then, another problem of management is that the water losses in the distribution can reach 20% again. The shortage irrigation water resource allocated has constrained the farmers to use groundwater. The chemical analysis of 56 simples to this water showed a significant chemical diversity in the compositions. There is a high salinity risk (C3 class) or very high risk (C4 class) of soil salinisation. A space chart distribution to the EC water probability to exceed 2.25 dS/m interpolated by the indicator kriging method showed that 78% of the groundwater surface presents a significant probability to exceed this limit. The average value of the SAR (sodium adsorption ratio) is lower than 10 that indicates a moderate risk of sodisation. This observation is in contradiction with the high values of the SAR measured in the soil solution. The approach of residual alkalinity (RSC) shows that a good number of drillings analyzed presents a positive sign RSC (RSC 〉 0). This water presents a real danger of sodisation. They have a low salinity, which, for a farmer, does not present any danger. 展开更多
关键词 Management water irrigation GROUNDWATER water quality.
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Theoretical Study of the AIEt3-Promoted Tandem Reductive Rearrangement of Epoxides
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作者 Li-dong Zhang Hui-jun Guo +1 位作者 Yang Pan Fei Qi 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第6期547-554,共8页
The AIEt3-promoted tandem reductive rearrangement reactions of epoxides was studied at B3LYP/6- 31C(d,p) level. For the model compound α-hydroxy epoxides, two possible reaction pathways Ⅰ and Ⅱ were calculated. T... The AIEt3-promoted tandem reductive rearrangement reactions of epoxides was studied at B3LYP/6- 31C(d,p) level. For the model compound α-hydroxy epoxides, two possible reaction pathways Ⅰ and Ⅱ were calculated. The main difference is the order of ethylene release and six- to five-member ring rearrangement. The ring contraction rearrangement in pathway Ⅰ is the first step and this step is the rate controlling step with a free energy barrier of 116.62 kJ/mol. For pathway Ⅱ, the ethylene release occurs first, and is followed by a six-member ring opening reaction which is the rate controlling step, and the barrier is 251.38 kJ/mol. The reason for such high barrier is that the ethylene release results in the following reaction being more difficult. The results show that pathway Ⅰ (C-C rearrangement and then ethylene release) is more favorable, which is consistent with experimental results. 展开更多
关键词 AIEt3 REARRANGEMENT Density functional theory DIOL EPOXIDE
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The Impact of the South Asia High Bimodality on the Chemical Composition of the Upper Troposphere and Lower Stratosphere 被引量:14
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作者 YAN Ren-Chang BIAN Jian-Chun FAN Qiu-Jun 《Atmospheric and Oceanic Science Letters》 2011年第4期229-234,共6页
The South Asia High (SAH) is the dominant feature of the circulation in the upper troposphere and lower stratosphere (UTLS) during the boreal summer, and the upper tropospheric anticyclonic circulation extends int... The South Asia High (SAH) is the dominant feature of the circulation in the upper troposphere and lower stratosphere (UTLS) during the boreal summer, and the upper tropospheric anticyclonic circulation extends into the lower stratosphere. The preferred locations of the center of the SAH occur in two different regions, and the center can be located over the Iranian Plateau or over the Tibetan Plateau. This bimodality has an impact on the distribution of chemical constituents in the UTLS region. We analyzed water vapor (H20), carbon monoxide (CO), and ozone (03) data derived from the Aura Microwave Limb Sounder (MLS) and total column ozone data from the Ozone Monitoring Instrument (OMI). For the Iranian Plateau mode of the SAH, the tropospheric tracers exhibited a positive anomaly over the Iranian Plateau and a negative anomaly over the Tibetan Plateau, whereas the stratospheric tracer exhibited a negative and a positive anomaly over the Iranian Plateau and the Tibetan Plateau, respectively. For the Tibetan Plateau mode, however, the distribution of the anomaly was the reverse of that found for the chemical species in the UTLS region. Furthermore, the locations of the extrema within the anomaly seemed to differ across chemical species. The anomaly extrema for H20 occurred in the vicinity of the SAH ridgeline, whereas CO and O3 exhibited a northward shift of 4-8 degrees. These impacts of the variation in the SAH on the chemical constitutes in the UTLS region can be attributed in part to the dynamical structure delineated by the tropopause field and the temperature field at 100 hPa. 展开更多
关键词 SAH UTLS chemical composition BIMODALITY
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Efficient development of Type-Ⅱ TiO_2 heterojunction using electrochemical approach for an enhanced photoelectrochemical water splitting performance
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作者 Yuanxing Fang Yiwen Ma Xinchen Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第3期438-445,共8页
Type‐II‐heterojunction TiO2nanorod arrays(NAs)are achieved by a combination of reduced and pristine TiO2NAs through a simple electrochemical reduction.The heterojunction‐structured TiO2NAs exhibit an enhanced photo... Type‐II‐heterojunction TiO2nanorod arrays(NAs)are achieved by a combination of reduced and pristine TiO2NAs through a simple electrochemical reduction.The heterojunction‐structured TiO2NAs exhibit an enhanced photo‐efficiency,with respect to those of pristine TiO2NAs and completely reduced black TiO2.The improved efficiency can be attributed to a synergistic effect of two contributions of the partially reduced TiO2NAs.The light absorption is significantly increased,from theUV to the visible spectrum.Moreover,the type II structure leads to enhanced separation and transport of the electrons and charges.The proposed electrochemical approach could be applied to various semiconductors for a control of the band structure and improved photoelectrochemical performance. 展开更多
关键词 Type II heterojunction structure Photoelectrochemical water splitting TIO2 Electrochemical reduction MODIFICATION
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Effects of 60Co-γ Ray Radicidation on Instant Tea 被引量:2
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作者 Wang Qian,Peng Ling,Li Wenge,and Deng Gangqiao Hunan Institute of Atomic Energy Application in Agriculture,Changsha,Hunan 410125 《Hunan Agricultural Science & Technology Newsletter》 2001年第1期21-23,共3页
Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and ... Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and maximum tolerance dose of 8.0KGy were proposed. 展开更多
关键词 instant tea radicidation D10 value
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Petro Logical Chemical Investigations for Characterization of Marble Stones Discovered Konar-Sandal (Jiroft-lran)
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作者 Parvin Soleimani Seyyed Mohammad Amin Emami 《Journal of Earth Science and Engineering》 2015年第4期241-250,共10页
Jiroft region is one of the most historical cities, placed in the southeastern of Iranian plateau. Its history dates back to the second millennium B.C. The ancient history of Jiroft and its proximity to the River ofHa... Jiroft region is one of the most historical cities, placed in the southeastern of Iranian plateau. Its history dates back to the second millennium B.C. The ancient history of Jiroft and its proximity to the River ofHalil Roud have attracted archeologists during the recent decades. So far various historical works have been unearthed from the region of which marble ones are especially noteworthy. Basically, marble works were used more commonly in central plateau of Iran than other ones. The marble works discovered in Jirofl region are only comparable with those from the recently excavation at Shahr-I Sokhta in Zabol. The scientific examination of such works may pave way to identify their internal structures and to compare them in terms of their provenance. The present study will focus on the characterization of marbles discovered in Konar Sandal, Jiroft. In addition to petro graphical studies, XRD and XRF investigations were used to identify the crystalline structures as well as balk chemical composition of the discovered marbles. The obtained results revealed that the major constituents of the discovered marbles in Jiroft were Ca and CaO. The structure of discovered marbles had orderly compact patterns resulted mainly from metamorphism conditions. This structure is actually Unsimilar to those from Shahr-I Sokhta. 展开更多
关键词 ARCHAEOMETRY ARCHAEOLOGY PETROLOGY MARBLE Jiroft.
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Oil shale resources in China and their utilization 被引量:2
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作者 XU Zhi ZHU Jianwei +1 位作者 DONG Qingshui SUN Pingchang 《Global Geology》 2016年第1期48-54,共7页
The unconventional oil and gas resources presented in oil shales have meant these potential sources of hydrocarbons, which has become a research focus. China contains abundant oil shale resources, ranking fourth in th... The unconventional oil and gas resources presented in oil shales have meant these potential sources of hydrocarbons, which has become a research focus. China contains abundant oil shale resources, ranking fourth in the world, with ca. 7 254.48 x 108 t within 24 provinces, including 48 basins and 81 oil shale deposits. A- bout 48% of the total oil shale resources are concentrated in the eastern resource region, with a further 22% in the central resource region. 65 % of the total quantity of oil shale resources is present at depths of 0-500 m, with 17% of the total resources being defined as high-quality oil shales yielding more than 10% oil by weight. Chinese oil shale resources are generally hosted by Mesozoic sediments that account for 78% of the total re- sources. In terms of the geographical distribution of these resources, some 45% are located in plain regions, and different oil shale basins have various characteristics. The oil shale resources in China represent a highly prospective future source of hydrocarbons. These resources having potential use not only in power generation and oil refining but also in agriculture, metal and chemical productions, and environmental protection. 展开更多
关键词 China oil shale RESOURCES DISTRIBUTION UTILIZATION
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Dynamic Simulation on Surface Hydration and Dehydration of Monoclinic Zirconia
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作者 Guang-Jie Xia Yang-Gang Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第4期629-638,I0038-I0055,I0149,I0150,共30页
The commonly used oxide-supported metal catalysts are usually prepared in aqueous phase,which then often need to undergo calcination before usage.Therefore,the surface hydration and dehydration of oxide supports are c... The commonly used oxide-supported metal catalysts are usually prepared in aqueous phase,which then often need to undergo calcination before usage.Therefore,the surface hydration and dehydration of oxide supports are critical for the realistic modeling of supported metal catalysts.In this work,by ab initio molecular dynamics(AIMD)simulations,the initial anhydrous monoclinic ZrO_(2)(111)surfaces are evaluated within explicit solvents in aqueous phase at mild temperatures.During the simulations,all the two-fold-coordinated O sites will soon be protonated to form the acidic hydroxyls(HO_(L)),remaining the basic hydroxyls(HO^(∗))on Zr.The basic hydroxyls(HO^(∗))can easily diffuse on surfaces via the active proton exchange with the undissociated adsorption water(H_(2)O^(∗)).Within the temperatures ranging from 273 K to 373 K,in aqueous phase a certain representative equilibrium hydrated m-ZrO_(2)(¯111)surface is obtained with the coverage(θ)of 0.75 on surface Zr atoms.Later,free energies on the stepwise surface water desorption are calculated by density functional theory to mimic the surface dehydration under the mild calcination temperatures lower than 800 K.By obtaining the phase diagrams of surface dehydration,the representative partially hydrated m-ZrO_(2)(111)surfaces(0.25≤θ<0.75)at various calcination temperatures are illustrated.These hydrated m-ZrO_(2)(111)surfaces can be crucial and readily applied for more realistic modeling of ZrO_(2) catalysts and ZrO_(2)-supported metal catalysts. 展开更多
关键词 ZrO_(2) Ab initio molecular dynamics Surface hydration Phase diagram CALCINATION
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