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农户收入结构变动分析 被引量:3
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作者 陈汉圣 武志刚 《经济研究参考》 1998年第6期23-32,共10页
一、引言 1978年以前,中国农户的收入结构变动十分缓慢。1978年后,农业中引入了联产承包责任制,实行了产业结构调整,提高了农产品价格,农户在获得了生产自由的同时,开始跨地区流动等等,这一切促进了农户收入水平的提高和收入结构的增长。
关键词 农户收入结构 农户收入水平 现金收入 收入份额 家庭经营收入 变动分析 年总收入 中国农户 货币收入 金性
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高效液相色谱法测定中药中的五种禁用黄色工业染料 被引量:13
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作者 翟海云 刘振平 +2 位作者 余晓 苏子豪 温飞容 《化学研究与应用》 CAS CSCD 北大核心 2014年第1期135-139,共5页
建立了反相高效液相色谱法同时测定五种中药中的五种工业染料(金胺O、橙黄G、金橙II、碱性橙II和皂黄)的方法。色谱柱为Kromasil C18(4.6 mm&#215;250 mm,5μm);检测波长为430 nm;温度30℃;流动相为甲醇-水-乙酸铵(20 mmol.L-... 建立了反相高效液相色谱法同时测定五种中药中的五种工业染料(金胺O、橙黄G、金橙II、碱性橙II和皂黄)的方法。色谱柱为Kromasil C18(4.6 mm&#215;250 mm,5μm);检测波长为430 nm;温度30℃;流动相为甲醇-水-乙酸铵(20 mmol.L-1),梯度洗脱;流速1.0 mL.min-1。金胺O、橙黄G、金橙II、碱性橙II和皂黄的方法检出限分别为(0.05、0.5、0.2、0.1和0.2μg.mL-1)(S/N=3)。样品的平均加标回收率为92.28-109.1%, RSD为0.56-1.5%。在供试品蒲黄和黄芩中检出工业染料金胺O。方法可用于五种常见中药中相关非法添加染料的检测。 展开更多
关键词 中药 掺假品 皂黄
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IMPROVEMENT ON TENSILE PROPERTIES AND CREEP RESISTANCE OF Fe 3Al BASED ALLOYS 被引量:1
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作者 姚正军 孙扬善 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期135-139,共5页
Effects of alloying processing on tensile test properties of Fe 3Al based alloys have been studied. Results show that microalloying of cerium is very effective on increasing the room temperature ductility of Fe 3Al... Effects of alloying processing on tensile test properties of Fe 3Al based alloys have been studied. Results show that microalloying of cerium is very effective on increasing the room temperature ductility of Fe 3Al based alloys. Surface analysis by XPS demonstrates that cerium addition causes the change in the oxide chemistry and provides rapid passivation of the specimen surface. The high temperature strength and creep resistance of Fe 3Al based alloys can be significantly enhanced by alloying additions of tungsten, niobium or molybdenum, especially when combined additions of tungsten with niobium or molybdenum are used. The additions of tungsten, niobium or molybdenum also result in the significant microstructural refinement and the formation of fine precipitates which are identified as M 6C type carbide in the alloys containing tungsten. 展开更多
关键词 materials Fe 3Al tensile and creep resistance properties MICROALLOYING
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HARDNESS PROPERTY AND WEAR RESISTANCE OF Al_2O_(3P)/ Zn-Al COMPOSITE
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作者 陶杰 崔益华 +3 位作者 肖军 冯健 邹香甫 李顺林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期155-160,共6页
The hardness values and the wear resistance of Al2O3P/ Zn-Al composite, prepared by means of rheological casting technology,are investigated separately in this work. The results show that the addition of Al2O3P increa... The hardness values and the wear resistance of Al2O3P/ Zn-Al composite, prepared by means of rheological casting technology,are investigated separately in this work. The results show that the addition of Al2O3P increases the hardness values of the matrix at both room and high temperature and improves the wear resistance of the material.The hardness values and the wear resistance of the composite rise with the increase of the particle volume fraction or the decrease of the particle size.The raising of test temperature results in a rapid descending of its hardness values.However, the addition of Al2O3P improves the property of high temperature resistance of Zn-Al alloys significantly.Moreover,the effect of quenching, tempering or cycling heat treatment on the hardness values of the composite is also studied. 展开更多
关键词 metallic matrix composites zinc alloys wear resistance Al_2O_(3P) particles hardness value
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行政性收费纳入预算管理可能引发的问题
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作者 钟川 《经济研究参考》 1997年第5期20-21,共2页
1.行政性收费纳入预算管理后其资金性质发生了质的变化。单位实行列收列支后,由预算外资金变成了预算内资金,财政对它的管理由“代理管理”——实行“
关键词 行政性收费 预算管理 代理管理 预算内资金 金性 预算外资金 年报分析 财政预算内收入 预算外收支 财政责任
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STUDY ON FLOW STRESS OF 7022 ALUMINUM ALLOY SHEET UNDER DIFFERENT TEMPERATURES AND STRAIN RATES 被引量:7
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作者 汪洪峰 左敦稳 +2 位作者 黄铭敏 陈明和 缪宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期248-254,共7页
Warm tensile tests for aluminum alloy 7022 sheet are held at different temperatures and strain rates. The range of temperature is 293-773 K and that of the strain rate is 0. 001-0.1 s^-1. The warm tensile properties,r... Warm tensile tests for aluminum alloy 7022 sheet are held at different temperatures and strain rates. The range of temperature is 293-773 K and that of the strain rate is 0. 001-0.1 s^-1. The warm tensile properties,relations among temperature,strain rate,and the flow stress are discussed. Constitutive equations under the warm tension are obtained based on revised Hooke law and Grosman equation. It is concluded that flow stress declines with the increase of the temperature and the decrease of the strain rates. The elongation percentage increases with the increase of the temperature and the decrease of strain rate. 展开更多
关键词 constitutive equations plastic flow ELASTIC-PLASTIC warm tension 7022 aluminum alloy
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Study on the Dielectric Properties of Chemical Vapor Deposited Diamond Film
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作者 汪浩 王秀芬 +1 位作者 郭林 朱鹤孙 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期274-279,共6页
Aim To study the dielectric properties of diamond film. Methods Dielectric properties (the frequency dependenCe of conductance, permittivity, and loss factor) of diamond film preped by DC are plasma jet chemical vap... Aim To study the dielectric properties of diamond film. Methods Dielectric properties (the frequency dependenCe of conductance, permittivity, and loss factor) of diamond film preped by DC are plasma jet chemical vapor deposition (CVD) were studied. Resuls Dielectric properties of CVD diamond fAn depend mainly on its polycrystalline nature, and the presence of non-diamond disordered graphitic regions and impurities between diamond grains of the film. Annealing at 500℃ leads to the removal of greater part of disordered graphitic regions, but am not remove all disordered graphitic regions and impurities. Conclusion Much work nab to be done tO prepare or post-treat diamond films before using CVD diamond as a substrate for electronic devices. 展开更多
关键词 dielectric properties diamond film DC are plasma jet CVD
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An Experimental Study of Cutting Performance of Ti(C, N) Based Cermet Cutting Tool
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作者 庞思勤 于启勋 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期173+168-173,共7页
Through systematic cutting experiments, characteristics of the cutting performance of Ti(C, N) based cermets is identified. The experiments were designed to study their resistance,toughness, cutting force, tool-chip f... Through systematic cutting experiments, characteristics of the cutting performance of Ti(C, N) based cermets is identified. The experiments were designed to study their resistance,toughness, cutting force, tool-chip friction coefficient and machining quality by comparing them with those of WC based cemented carbides. The cutting data and the regressed empirical formulae would be useful to promote proper application of cermet cutting tool materials. 展开更多
关键词 metal ceramics metal cutting cutting ability cutting tests
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FABRICATION OF DLC COATED COBALT-CEMENTED TUNGSTEN CARBIDE MICRO-DRILLS AND THEIR CUTTING PERFORMANCE 被引量:4
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作者 马玉平 陈明 +1 位作者 向道辉 孙方宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期89-93,共5页
In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cem... In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cemented tungsten carbide micro-drills with two-step pretreatment method. Characteristics of DLC coated tools are investigated in bias-enhanced HFCVD system with the optimized hot filament arrangement. The optimization deposition technology is obtained and the wear mechanism of cutting tools is analyzed. The drilling performance of DLC coated tools is verified by the experiments of cutting particle reinforced aluminum based composite material (Si 15% in volume) compared with uncoated ones. Experimental results show that the two-step pretreatment method is appropriate for complex shaped cemented carbide substrates and ensures the good adhesive strength between the diamond film and the substrate. The cutting performance of DLC coated tool is enhanced 10 times when machining the Si particle reinforced aluminum based metal matrix composite compared with that of uncoated ones under the same cutting conditions. 展开更多
关键词 DLC film bias-enhanced HFCVD cobalt-cemented tungsten carbide cutting tool micro-drilling cutting performance
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Some New Results from the Electron Theory on the Elastical of Alkahoe Earth Metals and Rare Earth Elements
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作者 崔秀山 邢胜娣 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期31+26-32,共8页
With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatl... With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatly refined, with the single exception of the theoreticalvalue of Young's modulus for Pr which is slightly increased This points to the validityof the new theory, that the bulk modulus is independent of the Poisson's ratio, and further that the valency electron structures of solids as determined by Yu's theory are correct. 展开更多
关键词 alkaline earth metals rare earth elements/electron theory of elasticity
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Modeling and Identification of Anisotropic Damping Property of Ni-Based Alloys by FEM-Simulation
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作者 韩建保 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期255-259,共5页
The modeling and identification of anisotropic damping property of Ni based single crystal alloys are presented. The anisotropic material damping property is modeled by 3 D rheological equations and identified by us... The modeling and identification of anisotropic damping property of Ni based single crystal alloys are presented. The anisotropic material damping property is modeled by 3 D rheological equations and identified by using specimen modal damping ratios and FEM simulation. The measured damping ratios which exhibit strong anisotropy are predicted better by the method presented than by other methods. 展开更多
关键词 single crystal alloy ANISOTROPY modal analysis FEM simulation
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Research on the Anticorrosion Coating Under the Paved Layer for Highway Steel Box Bridge Deck 被引量:4
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作者 SHEN Cheng-jin MING Tu-zhang +2 位作者 HU Guang-wei OU Xue-mei GEN Ou 《Journal of China University of Mining and Technology》 EI 2006年第4期429-432,共4页
The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely ... The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely different materials: a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt con- crete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings. 展开更多
关键词 steel bridge deck zinc coatings asphalt concrete paved layer
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Effect of Carrier Processing Temperature on Its Properties for Adsorption of Active Metals 被引量:2
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作者 Zeng Shuangqin Yang Qinghe +2 位作者 Li Dingjiangyi Nie Hong Li Dadong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第2期1-6,共6页
The influence of the carrier pseudo-boehmite (PB), which was impregnated with a Ni-Mo-P solution under over- saturation conditions and treated at different temperatures, on its property for adsorption of active meta... The influence of the carrier pseudo-boehmite (PB), which was impregnated with a Ni-Mo-P solution under over- saturation conditions and treated at different temperatures, on its property for adsorption of active metals (Ni, Mo) was studied. The results showed that the amount for adsorption of active metal was decreased with an increasing treatment tem- perature of the carrier. After phase transition of the carrier PB to γ-Al2O3, its capacity for adsorption of active metals was significantly reduced. The difference in properties for adsorption of active metals (Ni, Mo) by PB dried at 120℃ and γ-Al2O3 calcined at 600℃ was studied in detail. The results suggested that the ability of the PB carrier to adsorb metals was higher than that of theγ-Al2O3 carrier. Especially, the ratio of chemically adsorbed metals on the PB support was much higher than 3'-alumina. The chemical adsorption sites on the PB carrier were proved to be much more than those on the γ-Al2O3 carrier. Ni and Mo chemical adsorption sites differed a lot on the carrier possibly because of the difference in chemical adsorption sites. 展开更多
关键词 PSEUDO-BOEHMITE Γ-AL2O3 hydrogenation catalyst CARRIER ADSORPTION
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INVESTIGATION ON MECHANICAL PROPERTIES OF ZN-AL/SIC PARTICULATE COMPOSITES
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作者 陶杰 肖军 +2 位作者 崔益华 李顺林 沃丁柱 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期23-29,共7页
In order to improve the properties of ZA 27 and ZA4-3 zinc alloys and broaden their application ranges,SiC particlj1Ale composites, prepared by means of rheological casting technology, are investigated individually on... In order to improve the properties of ZA 27 and ZA4-3 zinc alloys and broaden their application ranges,SiC particlj1Ale composites, prepared by means of rheological casting technology, are investigated individually on their rT..t'llanical properties. The results of ne-cural strength, impact strensttl, compressive strength, hardness values and wear rate of the composites show that the addition of SiCp, leads to the increase of the compressive strength and hardness values at both room and higher temperature, and wear resistance of the materials, accompanying with the slight decrease of the fie-cural strength and sharp reduction of the impacttoughness. The factors affecting the mechanical properties of the composites are discussed in the paper. 展开更多
关键词 metal matrix composite zinc alloy SiC particle rheological casting technology mechanical properties
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Competitive adsorption of heavy metal ions on peat 被引量:5
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作者 LIU Zhi-rong ZHOU Li-min +3 位作者 WEI Peng ZENG Kai WEN Chuan-xi LAN Hui-hua 《Journal of China University of Mining and Technology》 EI 2008年第2期255-260,共6页
The uptake capacities, and the adsorption kinetics, of copper, Cu(Ⅱ), nickel, Ni(Ⅱ), and cadmium, Cd(Ⅱ), on peat have been studied under static conditions. The results show that the adsorption rates are rapid... The uptake capacities, and the adsorption kinetics, of copper, Cu(Ⅱ), nickel, Ni(Ⅱ), and cadmium, Cd(Ⅱ), on peat have been studied under static conditions. The results show that the adsorption rates are rapid: equilibrium is reached in twenty minutes. The adsorption of copper, nickel and cadmium is pH dependent over the pH range from 2 to 6. The adsorption kinetics can be excellently described by the Elovich kinetic equation. The adsorption isotherm fits a Langmuir model very well. The adsorption capacities follow the order Cu^2+ 〉 Ni^2+〉 Cd^2+ in single-component systems and the competitive adsorption capacities fall in the decreasing order Cu^2+ 〉 Ni^2+〉 Cd^2+ in multi-component systems. The adsorption capacities of these three heavy metal ions on peat are consistent with their observed competitive adsorption capacities. 展开更多
关键词 PEAT COPPER NICKEL CADMIUM competitive adsorption
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Non-Hodgkin's Lymphoma Primarily Presenting with Fanconi Syndrome and Acute Kidney Injury 被引量:2
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作者 Wen-ling Ye Bing Han +5 位作者 Bing-yan Liu Chan Meng Wei Ye Yu-bing Wen Hang Li Xue-mei Li 《Chinese Medical Sciences Journal》 CAS CSCD 2010年第3期185-188,共4页
KIDNEY involvement is common in non-Hodgkin's lymphoma (NHL) with incidence up to 30%-40% in autopsy studies. However, it us- ually occurs late in the course of the diseaseand is clinically silent. Clinically overt... KIDNEY involvement is common in non-Hodgkin's lymphoma (NHL) with incidence up to 30%-40% in autopsy studies. However, it us- ually occurs late in the course of the diseaseand is clinically silent. Clinically overt renal disease including acute kidney injury (AKI) as its primary manifestation is rarely reported, moreover, Fanconi syndrome (FS) is extremely rare as the main manifestation in NHL. In this report, we presented a case of NHL primarily presenting with FS and AKI due to diffuse interstitial infiltration of NHL cells and emphasized the important role of renal biopsy, especially renal immunohistochemical analysis in the diagnosis of renal diffuse lymphoma. 展开更多
关键词 non-Hodgkin's lymphoma Fanconi syndrome acute kidney injury
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Comparison of Clinical Effects of Au-Pt Based and Ni-Cr Based Porcelain Crowns 被引量:3
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作者 Li-chun Wu Ye Shi Teng Ma 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第3期167-170,共4页
Objective To compare the long-term clinical effects of two kinds of crowns and bridges made of porcelain fused to Au-Pt alloy and Ni-Cr alloy. Methods A total of 131 teeth (64 patients) were rehabilitated using porcel... Objective To compare the long-term clinical effects of two kinds of crowns and bridges made of porcelain fused to Au-Pt alloy and Ni-Cr alloy. Methods A total of 131 teeth (64 patients) were rehabilitated using porcelain-fused-to-metal crowns, among which 59 were rehabilitated with Au-Pt alloy metal ceramic crown and 72 with Ni-Cr alloy metal ceramic crown. The porcelain fracture, shade, marginal adaptation, gingival discoloration, and gingival status after finishing restoration and 36 months of follow-up were evaluated. Results After 36 months of restoration, porcelain fused to Au-Pt alloy crown showed better clinical effects than porcelain fused to Ni-Cr alloy crown in shade, marginal adaptation, gingival discoloration, as well as gingival status (all P<0.05). Conclusion The Au-Pt alloy ceramic crown is superior to Ni-Cr alloy ceramic crown in long-term clinical effects. 展开更多
关键词 Au-Pt alloy Ni-Cr alloy porcelain-fused-to-metal crown clinical evaluation
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Commercial Application of Polymetallic Reforming Catalysts PRT 被引量:2
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作者 Chen Zhixiang Zhang Daqing +1 位作者 Liu Zhihua Zang Gaoshan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第3期5-9,共5页
The commercial application results showed that the polymetallic reforming catalysts PRT exhibited high activity, good selectivity and stability. The performance of said catalysts could be restored completely through r... The commercial application results showed that the polymetallic reforming catalysts PRT exhibited high activity, good selectivity and stability. The performance of said catalysts could be restored completely through regeneration. After long period of operation, the activity of said catalysts still exhibited good sensitivity to temperature rise. Compared with the PR series catalysts, the PRT series catalysts had obviously better stability and lower coking rate. 展开更多
关键词 PRT series catalyst REFORMING commercial application coking rate
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Study on GNi-WC25 Coating by High Frequency Induction Cladding 被引量:3
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作者 张增志 韩桂泉 +1 位作者 付跃文 沈立山 《Journal of China University of Mining and Technology》 2002年第2期158-162,共5页
Process and mechanism of high frequency were studied in this paper by means of cold attachment for the preparation of GNi WC25 coating . The results show its special distribution law of eddy current while the magnetic... Process and mechanism of high frequency were studied in this paper by means of cold attachment for the preparation of GNi WC25 coating . The results show its special distribution law of eddy current while the magnetic transition temperature and electric resistivity of the coating have been measured .Wear resistance of the high frequency induction coating has an advantage over those of laser cladding coating and oxygen acetylene spraying fusing coating . Moreover , the GNi WC25 coating by high frequency induction cladding has smooth surface and even microstructure. 展开更多
关键词 high frequency induction cladding GNi WC25 COATING
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Development of New Generation Catalysts for Selective Hydrodesulfurization of FCC Naphtha 被引量:5
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作者 Chu Yang Li Mingfeng +3 位作者 Li Huifeng Qu Jinhua Nie Hong Li Dadong (Research Institute of Petroleum Processing, SINOPEC Corp., Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第1期19-23,共5页
The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 c... The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national IV emission standard and the Euro V emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability. 展开更多
关键词 FCC gasoline selective hydrogenation HYDRODESULFURIZATION catalyst anti-knock index
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