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Phase composition and luminescent properties of strontium aluminate long persistence phosphor synthesized by combustion synthesis method with different Sr/Al ratios 被引量:1
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作者 Wen-Zhou Sun Yu-Hong Chen +1 位作者 Lan-Er Wu Yong Jiang 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期414-419,共6页
Strontium aluminate long persistence phos phors are synthesized by combustion method. By control- ling the raw material ratio (Sr/Al), the effects of phase composition on subsequent spectroscopic properties of phosp... Strontium aluminate long persistence phos phors are synthesized by combustion method. By control- ling the raw material ratio (Sr/Al), the effects of phase composition on subsequent spectroscopic properties of phosphors are studied. Results show that the phase com-position changes from strontium-rich phase to aluminum- rich phase with the decrease of Sr/AI: when the rate of Al/Sr changes from 3:1 to 1:1, the main crystal phase of samples is Sr3Al206, and it exhibits the characteristic fluorescence of Eu^3+ in the lattice of Sr3Al206; when the rate of Al/Sr is between 1:2 and 2:7, phase composition is the mixture of SrAl204 and SrAl4OT, and it emits the characteristic fluorescence of Eu^2+ in SrAl204 but not in SrAl4OT; when Al/Sr decreases to 1:4 or even 1:12, the main crystal phase of samples transform into SrAl12019, and the characteristic emission peak is about 470 nm, which corresponds to the characteristic emission of Eu2+ in SrAl12019. At the end of the article, the influence laws of two different synthesis methods on phase composition of samples between high-temperature solid method and combustion method are compared. Compared with the high-temperature solid method, the rule of influence is similar, but the mole ratio of Al/Sr in products is always higher than the initial ratio of the raw material, and com-pounds like Sr4Al14025 are not obtained by combustion method. 展开更多
关键词 Strontium aluminate long persistencephosphors Combustion synthesis Sr/Al ratio Phasecomposition Emission wavelength
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EFFECT OF COLD ROLLING RATIO OF CATALYST ON SYNTHESIS OF DIAMOND
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作者 Wang Zhifa, Li Wenxian, Chen Jiayan Department of Materials Science and Engineering, Central South University of Technology, Changsha 410083 《中国有色金属学会会刊:英文版》 CSCD 1997年第3期58-60,148,共4页
EFFECTOFCOLDROLLINGRATIOOFCATALYSTONSYNTHESISOFDIAMOND①WangZhifa,LiWenxian,ChenJiayanDepartmentofMaterialsSc... EFFECTOFCOLDROLLINGRATIOOFCATALYSTONSYNTHESISOFDIAMOND①WangZhifa,LiWenxian,ChenJiayanDepartmentofMaterialsScienceandEnginerin... 展开更多
关键词 CATALYST DIAMOND synthesis COLD ROLLING ratio texture
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Correlation between hydrocarbon distribution and water-hydrocarbon ratio in Fischer-Tropsch synthesis
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作者 Xiaofeng Zhou Qingling Chen +1 位作者 Yuewu Yao Huixin Weng 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期525-530,共6页
In order to shorten the evaluation cycle of cobalt catalyst before the optimized catalyst is fixed on, a mathematical method is proposed to calculate weight percentage of C5+ hydrocarbons. Based on the carbide polyme... In order to shorten the evaluation cycle of cobalt catalyst before the optimized catalyst is fixed on, a mathematical method is proposed to calculate weight percentage of C5+ hydrocarbons. Based on the carbide polymerization mechanism and the main hydrocarbons being linear alkanes and α-olefins, the correlation between hydrocarbon distribution and the molecular mass ratio of water to hydrocarbons is discussed. The result shows the ratio was within the range of 1.125-1.286 and the lower the ratio, the more gaseous hydrocarbons were obtained. Moreover, a linear equation between the weight percentage of C5+ hydrocarbons and the weight ratio of C5+ hydrocarbons to the total water is established. These results are validated by corresponding experiments. The weight percentage of C5+ hydrocarbons could be immediately calculated by this linear equation without detailed gas chromatography (GC) analysis of them. 展开更多
关键词 Fischer-Tropsch synthesis cobalt catalyst water-hydrocarbon weight ratio hydrocarbon distribution
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A study on liver mitochondria respiration and protein synthesis in cold adapted rats
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作者 何开跃 杨泽田 《Journal of Medical Colleges of PLA(China)》 CAS 1992年第1期45-48,共4页
Mitochondria were isolated from normal and cold adapted rat livers.The respiratory func-tion of mitochondria in rat livers,including ADP:O ratio(P/O)and the respiratory control ratio(RCR),was determined by oxygen elec... Mitochondria were isolated from normal and cold adapted rat livers.The respiratory func-tion of mitochondria in rat livers,including ADP:O ratio(P/O)and the respiratory control ratio(RCR),was determined by oxygen electrode method,The protein synthesis in mitochondria wasstudied by observing the incorporation of[~3H]-Leucine into mitochondria.Polyacrylamide gelelectrophoresis was carried out to detect the changes of the inner membrane proteins.It was shownthat the P/O and RCR decreased in cold adapted rats in the 2nd and 4th weeks and returned tothe control level in the 6th week,the protein synthesis of mitochondria decreased significantly incold adapted rats in 1,2 and 4 weeks;the electrophoretic pattern of the inner membrane proteinsin mitochondria from cold adapted rat livers revealed some new bands. 展开更多
关键词 COLD adaptation MITOCHONDRIA liver oxidative PHOSPHORYLATION RESPIRATORY control ratio protein synthesis membrane proteins RATS
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Empirical Analysis of the Relationship between Price-Earnings Ratio and the Development of the Capital Markets
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作者 Laixi Xu 《经济管理学刊(中英文版)》 2018年第2期175-183,共9页
On the one hand,the P/E ratio measures growth opportunity,bubble level,and investment value of a company.On the other hand,the calculation of P/E is rather simple and convenient,and therefore considerably popular.This... On the one hand,the P/E ratio measures growth opportunity,bubble level,and investment value of a company.On the other hand,the calculation of P/E is rather simple and convenient,and therefore considerably popular.This article selects the monthly data for five years from 2012 to 2017,of all Shanghai A shares to conduct an empirical analysis.Based on the Gordon model,macroeconomic variables,time variable,technical indicators,and other variables are introduced to reflect the actual price-earnings ratio.This article innovatively introduces the OBV energy wave indicator in empirical research to measure the influence of market heat and investor sentiment on the price-earnings ratio.This paper regresses both on the whole data and on the data grouped according to the average earnings per share,and concludes that P/E estimated by Gordon model,company size,and time factor have a considerable degree of explanation for the actual price-earnings ratio,and the innovative introduction of OBV energy wave indicator also shows significant correlation and explanation. 展开更多
关键词 GORDON Model price-earnings ratio Panel Data
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Higher alcohol synthesis over Cu-Fe composite oxides with high selectivity to C_(2+)OH 被引量:12
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作者 Zhenghong Bao Kang Xiao +5 位作者 Xingzhen Qi Xinxing Wang Liangshu Zhong Kegong Fang Minggui Lin Yuhan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第1期107-113,共7页
Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2+OH and C6+OH in alcohol distribution was very high while the methane product... Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2+OH and C6+OH in alcohol distribution was very high while the methane product fraction in hydrocarbon distribution was rather low, demonstrating a promising potential in higher alcohols synthesis from syngas. The distribution of alcohols and hydrocarbons approximately obeyed Anderson-Schulz-Flory distribution with similar chain growth probability, indicating alcohols and hydrocarbons derived from the same intermediates. The effects of Cu/Fe molar ratio, reaction temperature and gas hourly space velocity (GHSV) on catalytic performance were studied in detail. The sample with a Cu/Fe molar ratio of 10/1 exhibited the best catalytic performance. Higher reaction temperature accelerated water-gas-shift reaction and led to lower total alcohols selectivity. GHSV showed great effect on catalytic performance and higher GHSV increased the total alcohol selectivity, indicating there existed visible dehydration reaction of alcohol into hydrocarbon. 展开更多
关键词 higher alcohol synthesis SYNGAS Cu-Fe composite oxides molar ratio GHSV
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Effect of C/S Ratio on Morphology and Structure of Hydrothermally Synthesized Calcium Silicate Hydrate 被引量:11
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作者 何永佳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期770-773,共4页
The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics... The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased. 展开更多
关键词 calcium silicate hydrate C/S ratio MORPHOLOGY STRUCTURE hydrothermal synthesis
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Hydrothermal Synthesis,Structure and Characterization of a New 2D Co(Ⅱ) Coordination Polymer Based on Flexible Double Imidazole Derivative and Oxalate 被引量:1
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作者 LIU Lian-li HUANG Jing-jing WANG Xiu-li LIU Guo-cheng YANG Song MU Bao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第6期942-946,共5页
A 1D supramolecular compound [dmbbbi](1) and a 2D cobalt coordination polymer [Co(dmbbbi)(ox)] 2(2) [dmbbbi=1,1-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole),ox=oxalate],C48H52Co2N8O8,were obtained under ... A 1D supramolecular compound [dmbbbi](1) and a 2D cobalt coordination polymer [Co(dmbbbi)(ox)] 2(2) [dmbbbi=1,1-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole),ox=oxalate],C48H52Co2N8O8,were obtained under hydrothermal conditions by tuning the molar ratio of the reactants.The crystal structure analysis reveals that in compound 1,the adjacent dmbbbi molecules connect with each other via hydrogen bonds to form a 1D supramolecular chain.In compound 2,two crystallographically independent Co2+ ions show the same six-coordination mode.Each Co2+ ion is coordinated by four oxygen atoms from two ox anions and two nitrogen atoms from two cis-dmbbbi ligands.The adjacent Co2+ ions are bridged by ox anions to generate an infinite 1D zigzag chain,which is extended by pairs of dmbbbi ligands to form a 2D honeycomb-like(6,3) network.Moreover,the thermal stability and the electrochemical property of compound 2 were studied. 展开更多
关键词 Hydrothermal synthesis Crystal structure Molar ratio Double imidazole derivative
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Direct synthesis of hydrogen peroxide over Pd nanoparticles embedded between HZSM-5 nanosheets layers 被引量:3
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作者 Guozhu Liu Hairui Liang +2 位作者 Yajie Tian Bofeng Zhang Li Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第10期2577-2586,共10页
Direct synthesis of hydrogen peroxide(DSHP)was studied over Pd loaded on HZSM-5 nanosheets(Pd/ZN).Pd nanoparticles with average size of ca.4.3 nm were introduced into the adjacent nanosheet layers(thickness of ca.2.9 ... Direct synthesis of hydrogen peroxide(DSHP)was studied over Pd loaded on HZSM-5 nanosheets(Pd/ZN).Pd nanoparticles with average size of ca.4.3 nm were introduced into the adjacent nanosheet layers(thickness of ca.2.9 nm)by impregnation method.Pd/ZN with theoretical Si/Al molar ratio of 25 showed the highest selectivity for H2O2 among the prepared catalysts,together with highest formation rate of H2O2(38.0 mmol·(g cat)^-1·h^-1),1.9 times than that of Pd supported on conventional HZSM-5 zeolite(Pd/CZ-50).Better catalytic performance of nanosheet catalysts was attributed to the promoted Pd dispersion which promoted H2 dissociation,more BrΦnsted acid sites and stronger metal-support interaction which inhibited the dissociation of O-O bond in H2O2.The embedded structure sufficiently protected the Pd nanoparticles by space confinement which restrained the Pd leaching,leading to a better catalytic stability with 90%activity retained after 3 cycles,which was almost 3 times than that of Pd/CZ-50(30.4%activity retained). 展开更多
关键词 HZSM-5 nanosheets Palladium catalyst Silica/alumina molar ratio Metal-support interaction Direct synthesis of hydrogen peroxide
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Constrained circular-patch-based texture synthesis
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作者 马荣飞 《Journal of Beijing Institute of Technology》 EI CAS 2011年第4期527-535,共9页
Texture synthesis has been developed for several years.The traditional technique can generate a larger image from a small image while avoid feeling of repetition or uncontinuity.Some constrained synthesis methods whic... Texture synthesis has been developed for several years.The traditional technique can generate a larger image from a small image while avoid feeling of repetition or uncontinuity.Some constrained synthesis methods which can synthesize image according to special location demand or other demands have been also proposed in recent years.However,in general,these constrained texture synthesis methods are simple and have few controllable factors to meet user's diverse needs.To control multiple-sample texture synthesis more flexibly in various aspects such as synthesis location,proportion and semantic objects,we present an interactive texture synthesis approach based on circular patches and constrained by objects according to a certain ratio.With this approach,source exemplars and the target image are firstly divided into several regions with different characters.Users can click the blocks in the source exemplars and the want-to-be-synthesized region in the target image,and then texture in the target image is synthesized with the corresponding regions in the source exemplars.In the process of texture synthesis,circular patch instead of square patch is used to eliminate the aliasing phenomena.Images are synthesized from multiple sample images with ratio constraint and experiments on images show that our approach can get effective results of ratio-constrained multi-sample synthesis. 展开更多
关键词 texture synthesis multiple sample circular patch ratio constraint
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Synthesis and Characterization of Magnesium Substituted Aluminophosphate Molecular Sieves with AEL Structure
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作者 BenjingXu LingQian XinmeiLiu ChunminSong ZifengYan 《Journal of Natural Gas Chemistry》 CAS CSCD 2004年第4期231-237,共7页
MAPO-11 molecular sieves were synthesized by hydrothermal methods. The influence of precursor of magnesium, Mg/Al ratio, synthesis temperature, synthesis time and the type of template on the formation and properties o... MAPO-11 molecular sieves were synthesized by hydrothermal methods. The influence of precursor of magnesium, Mg/Al ratio, synthesis temperature, synthesis time and the type of template on the formation and properties of MAPO-11 molecular sieves was examined. The samples were characterized by the techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric/differential thermogravimetric analysis (TG-DGA), etc. The results show that the shape and size of crystal were influenced by the precursor of Mg, the Mg/Al ratio and the type of template, and the TG-DGA analysis shows that MAPO-11 molecular sieves as-synthesized have poor thermal stability. 展开更多
关键词 MAPO-11 molecular sieves Mg/Al ratio synthesis temperature synthesis time
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Research on Synthesis of 4,5-Dihydroxy-1,3-Dimethyl-2-Imidazo-lidinone
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作者 沈勇 孙铠 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期32-34,共3页
The formaidehyde-free finishing agent 4,5-di-hydroxy-1,3-dimethy1-2-imidazolidinone(DMeDHEU)was prepared by the reaction of 1,3-dimethylurea and glyoxal.The reaction rate and equilib-rium conversion in relation to pH ... The formaidehyde-free finishing agent 4,5-di-hydroxy-1,3-dimethy1-2-imidazolidinone(DMeDHEU)was prepared by the reaction of 1,3-dimethylurea and glyoxal.The reaction rate and equilib-rium conversion in relation to pH value,molar ratio,temperature and catalyst were studied.The conversionto DMeDHEU,catalyzed with citric acid/anhydrousNaAc,reached 95% in 6 hours at 40℃, pH 5.5 andmolar ratio 1.2. 展开更多
关键词 formaldehyde - free finishing agent 4 5 - di-hydroxy -1 3- DIMETHYL - 2 - IMIDAZOLIDINONE (DMeD-HEU) synthesis reaction rate conversion ratio.
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水热法合成超细斜发沸石试验研究
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作者 吴照洋 郝小非 +2 位作者 孙启亮 张永兴 权藏玉 《化工矿物与加工》 CAS 2024年第1期15-20,共6页
斜发沸石具有较强的吸附和离子交换能力,在重金属和油污废水去除、制糖、造纸净化、抗菌抗癌药物助剂制备、石油化工催化裂化、国防以及CO_(2)脱除等领域应用广泛。为了获得纯度较高的斜发沸石,以NaOH、KOH、Al(OH)_(3)、Na_(2)O·n... 斜发沸石具有较强的吸附和离子交换能力,在重金属和油污废水去除、制糖、造纸净化、抗菌抗癌药物助剂制备、石油化工催化裂化、国防以及CO_(2)脱除等领域应用广泛。为了获得纯度较高的斜发沸石,以NaOH、KOH、Al(OH)_(3)、Na_(2)O·nSiO_(2)、H_(2)O为原料,采用水热法制备了斜发沸石,并通过XRD和晶面分析,研究了斜发沸石的合成条件,结果表明:合成斜发沸石的最佳条件为n(SiO_(2))/n(Al_(2)O_(3))=11、n(OH-)/n(SiO_(2))=0.55、n(H_(2)O)/n(SiO_(2))=25~55、温度150℃、时间6 d,合成的斜发沸石呈片状结构,特征峰完整,纯度较高,其晶胞组成为Na_(0.36)K_(6.58)[(AlO_(2))6(SiO_(2))_(25.26)]·6.71H_(2)O,n(SiO_(2))/n(Al_(2)O_(3))约为8.5,属中硅铝比沸石。SEM分析结果显示,其粒径在1.3μm以下,表明粒度非常细;其静态水吸附量为34.3%,达到了HG/T 2690-2012《13X分子筛》中的一等品指标要求。研究成果可为高纯度细粒斜发沸石的精准合成提供借鉴。 展开更多
关键词 斜发沸石 水热法 特征峰 硅铝比 合成条件 静态水吸附 晶面分析
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无有机胺醇水体系低硅铝比ZSM-5沸石的一步合成
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作者 张国林 郝文明 +3 位作者 秦波 杜艳泽 马静红 李瑞丰 《石油化工》 CAS CSCD 北大核心 2024年第9期1251-1258,共8页
研究了无有机胺醇水体系低硅铝比ZSM-5沸石的绿色合成方法。在无有机胺模板剂和不加晶种的醇水体系中,一步合成了形貌均一的小晶粒聚集体低硅铝比ZSM-5沸石,考察了合成体系中各配料的含量以及晶化温度对合成低硅铝比ZSM-5沸石的影响。利... 研究了无有机胺醇水体系低硅铝比ZSM-5沸石的绿色合成方法。在无有机胺模板剂和不加晶种的醇水体系中,一步合成了形貌均一的小晶粒聚集体低硅铝比ZSM-5沸石,考察了合成体系中各配料的含量以及晶化温度对合成低硅铝比ZSM-5沸石的影响。利用XRD、FTIR、SEM、N_(2)吸附-脱附、^(27)Al MAS NMR和^(29)Si MAS NMR等方法对合成的ZSM-5沸石进行表征。实验结果表明,当n(Si)∶n(Al)=20,n(Na_(2)O)∶n(SiO_(2))=0.071,n(C_(2)H_(5)OH)∶n(SiO_(2))=1.77,晶化温度为160℃时,可合成具有高结晶度的纯相ZSM-5沸石。^(27)Al MAS NMR表征结果显示,合成的ZSM-5沸石主要含有骨架四配位铝,无非骨架铝。合成的ZSM-5沸石的比表面积和微孔孔体积分别为384 m^(2)/g和0.14 cm^(3)/g,总酸量达到789μmol/g,骨架n(Si)∶n(Al)=14.4。 展开更多
关键词 无有机胺体系 低硅铝比ZSM-5沸石 水热合成
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爆轰管内氢氧爆炸过程与碳-铁纳米材料生长研究
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作者 赵铁军 刘翼 +2 位作者 吴永翔 闫鸿浩 吴林松 《爆炸与冲击》 EI CAS CSCD 北大核心 2024年第11期39-48,共10页
为研究气相爆轰合成碳-铁纳米材料的爆炸过程,采用氢氧爆炸试验与数值模拟相结合的方式研究了不同氢氧摩尔比(2∶1、3∶1和4∶1)对爆轰参数(爆速、爆温、爆压)峰值时程曲线与碳-铁纳米材料形貌的影响。研究表明:爆轰管内氢氧爆炸包括爆... 为研究气相爆轰合成碳-铁纳米材料的爆炸过程,采用氢氧爆炸试验与数值模拟相结合的方式研究了不同氢氧摩尔比(2∶1、3∶1和4∶1)对爆轰参数(爆速、爆温、爆压)峰值时程曲线与碳-铁纳米材料形貌的影响。研究表明:爆轰管内氢氧爆炸包括爆轰波的传播与燃烧波的衰减2个过程,且氢氧摩尔比对爆速、爆温、爆压的峰值时程曲线影响十分显著。随着氢氧摩尔比的提高,爆轰波的爆速、爆温、爆压及其衰减速率均呈减小趋势。氢氧摩尔比通过影响爆轰波的传播与衰减而作用于碳-铁纳米材料形貌的生长。零氧平衡时,样品为碳包铁纳米颗粒,随着氢氧摩尔比的提高,样品中碳纳米管的数量逐渐增多。调整氢氧摩尔比可实现对爆轰波传播与衰减过程的控制,达到气相爆轰控制性制备特定形貌的碳-铁纳米材料的目的。 展开更多
关键词 爆轰合成 氢氧摩尔比 生长机理 碳-铁纳米材料
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Er_(2)SiO_(5)纳米粉体的并流共沉淀法合成
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作者 佟永乐 王雅雷 +3 位作者 刘蓉 刘怀菲 武囡囡 程慧聪 《材料工程》 EI CAS CSCD 北大核心 2024年第3期52-60,共9页
以Er_(2)O_(3)和正硅酸乙酯(TEOS)为原料,采用并流共沉淀法合成了纳米Er_(2)SiO_(5)粉体。研究了前驱体Si/Er摩尔比、煅烧温度以及反应体系pH值对Er_(2)SiO_(5)物相组成和显微结构的影响,并探讨了Er_(2)SiO_(5)粉体的合成机理。结果表明... 以Er_(2)O_(3)和正硅酸乙酯(TEOS)为原料,采用并流共沉淀法合成了纳米Er_(2)SiO_(5)粉体。研究了前驱体Si/Er摩尔比、煅烧温度以及反应体系pH值对Er_(2)SiO_(5)物相组成和显微结构的影响,并探讨了Er_(2)SiO_(5)粉体的合成机理。结果表明:前驱体Er/Si摩尔比为20∶12,煅烧温度为1300℃时,Er_(2)SiO_(5)粉体由X2-Er_(2)SiO_(5)纯相组成,具有近球形形貌特征。低Er/Si摩尔比可降低Er_(2)SiO_(5)的结晶温度并促进X2-Er_(2)SiO_(5)的生成,反应体系pH值的升高则对[Si—O—Er]结构的生成具有一定的促进作用。Er_(2)SiO_(5)前驱体是以[Si—O—Er]网络结构形式存在的,煅烧过程中通过分解和结构重组逐步生成Er_(2)SiO_(5),Er_(2)O_(3)杂质相的生成是高Er/Si摩尔比前驱体[Si—O—Er]网络结构中的Er^(3+)在Er_(2)SiO_(5)结晶过程中的析出造成的。 展开更多
关键词 Er_(2)SiO_(5)粉体 并流共沉淀法 Er/Si摩尔比 合成机理
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磷酸锰铁锂正极材料研究进展 被引量:4
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作者 刘帅杰 孙妍 邓子昭 《化工矿物与加工》 CAS 2024年第4期24-32,共9页
作为锂离子电池正极材料之一,磷酸锰铁锂具有能量密度大、安全性好、成本较低等优点,被认为是磷酸铁锂理想的升级品。但是,磷酸锰铁锂较低的电导率和Li^(+)扩散系数限制了其商业化应用。介绍了磷酸锰铁锂材料性能,总结了高温固相法、共... 作为锂离子电池正极材料之一,磷酸锰铁锂具有能量密度大、安全性好、成本较低等优点,被认为是磷酸铁锂理想的升级品。但是,磷酸锰铁锂较低的电导率和Li^(+)扩散系数限制了其商业化应用。介绍了磷酸锰铁锂材料性能,总结了高温固相法、共沉淀法、溶胶凝胶法、水热/溶剂热法等合成方法的优缺点,综述了碳包裹、纳米化及形貌控制、离子掺杂等改性策略,指出磷酸锰铁锂材料应具有一个合适的锰铁原子数量比;在总结前人研究成果的基础上,展望了未来磷酸锰铁锂正极材料的研究方向。 展开更多
关键词 正极材料 磷酸锰铁锂 合成方法 改性策略 锰铁原子数量比 碳包裹 离子掺杂
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腐霉利的合成及密度泛函理论研究
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作者 段海潮 马超 +2 位作者 柴明根 吕金星 焦艳晓 《广东化工》 CAS 2024年第3期53-55,共3页
我们以3,5-二氯苯胺、1,2-二甲基环丙烷-1,2-二甲酸甲酯(以下简称二甲酯)为原料制备得到了腐霉利。以降低原料消耗量,减少“三废”排放以及提高经济效益为目标,对腐霉利制备中的投料比、反应温度、溶剂进行了优化,确定了最佳反应条件。... 我们以3,5-二氯苯胺、1,2-二甲基环丙烷-1,2-二甲酸甲酯(以下简称二甲酯)为原料制备得到了腐霉利。以降低原料消耗量,减少“三废”排放以及提高经济效益为目标,对腐霉利制备中的投料比、反应温度、溶剂进行了优化,确定了最佳反应条件。当使用水作为溶剂,3,5-二氯苯胺与二甲酯的摩尔比为1∶1,反应温度100℃时,以高收率低消耗得到腐霉利。同时,将密度泛函计算与前线轨道理论相结合,对腐霉利可能的衍生方式进行研究。 展开更多
关键词 腐霉利 投料比 反应温度 合成 密度泛函理论
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液相色谱-稳定同位素比值质谱法测定针叶樱桃粉中抗坏血酸的碳稳定同位素比值
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作者 王道兵 冯迪 +10 位作者 曹翠峰 钟其顶 翟鹏贵 武竹英 岳红卫 童玲 张燚 洪玉玲 张红霞 徐胜 张洛琪 《食品与发酵工业》 CAS CSCD 北大核心 2024年第2期283-287,295,共6页
该文建立液相色谱-稳定同位素比值质谱联用(liquid chromatography-stable isotope ratio mass spectrometry,LC-IRMS)检测抗坏血酸δ^(13)C值的分析方法,用于鉴别针叶樱桃粉中抗坏血酸天然来源的真实性。样品中抗坏血酸经液相色谱在线... 该文建立液相色谱-稳定同位素比值质谱联用(liquid chromatography-stable isotope ratio mass spectrometry,LC-IRMS)检测抗坏血酸δ^(13)C值的分析方法,用于鉴别针叶樱桃粉中抗坏血酸天然来源的真实性。样品中抗坏血酸经液相色谱在线分离纯化,优化后色谱条件为:Syncronis C18(250 mm×4.6 mm,5μm)色谱柱,流动相为水-pH 2的硫酸溶液(90∶10,体积比),流速0.250 mL/min,色谱柱温度30℃,进样量10μL,通过LC-IsoLink实现目标物全部氧化为CO_(2)气体,最终以气态形式进入稳定同位素质谱仪,直接检测样品中抗坏血酸的δ^(13)C,该方法结果稳定、准确。分别测定了7个合成来源的维生素C片和19个针叶樱桃粉,结果表明,天然来源抗坏血酸δ^(13)C值为-25.00‰~-22.01‰,合成来源抗坏血酸δ^(13)C值为-11.74‰~-10.28‰,两者分布显著性差异,该方法可用于抗坏血酸产品标识的真实性鉴别研究。 展开更多
关键词 针叶樱桃粉 抗坏血酸 液相色谱-稳定同位素比值质谱 天然 合成 δ^(13)C
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多变量预测控制(MPC)在甲醇合成氢碳比调节的应用分析
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作者 刘长伟 孟挺 +3 位作者 吴函 贾建峰 靳永勇 路嗣恩 《煤化工》 CAS 2024年第4期12-15,共4页
以中煤榆林205万t/a甲醇合成系统为研究对象,针对实际操作过程中氢碳比调整滞后导致合成塔温度波动及人工操作频繁等问题,引入多变量预测控制(MPC)系统,并结合实际操作中的控制难点和氢碳比影响因素,确定被控变量和操作变量,实现对甲醇... 以中煤榆林205万t/a甲醇合成系统为研究对象,针对实际操作过程中氢碳比调整滞后导致合成塔温度波动及人工操作频繁等问题,引入多变量预测控制(MPC)系统,并结合实际操作中的控制难点和氢碳比影响因素,确定被控变量和操作变量,实现对甲醇合成装置的精细化控制。实践应用情况表明:MPC系统能够提升装置生产平稳性,提高装置的自动化水平,降低生产过程操作人员的劳动强度,提升装置效益。 展开更多
关键词 甲醇合成 氢碳比 多变量预测控制(MPC) 节能降耗
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