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Stability in Liquid Phases of Molecular Compounds Composed of Saturated Atoms: Application with the Even-Odd Rule and a Specific Periodic Table for Liquids
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作者 Geoffroy Auvert Marine Auvert 《Open Journal of Physical Chemistry》 2022年第1期1-18,共18页
Building on the idea that molecules in liquid phase associate into multi-molecular complexes through covalent bonds, the present article focuses on the possible structures of these complexes. Saturation at atomic leve... Building on the idea that molecules in liquid phase associate into multi-molecular complexes through covalent bonds, the present article focuses on the possible structures of these complexes. Saturation at atomic level is a key concept to understand where connections occur and how far molecules aggregate. A periodic table for liquids with saturation levels is proposed, in agreement with the even-odd rule, for both organic and inorganic elements. With the aim at reaching the most stable complexes, meaning no other chemical reactions can occur in the liquid phase, the structure of complexes resulting from liquefaction of about 30 molecules is devised. The article concludes that complexes in liquids generally assume rounded shapes of an intermediate size between gas and solid structures. It shows that saturation and covalent bonds alone can explain the specific properties of liquids. While it is generally acknowledged that molecular energy in gases and solids are respectively linear kinetic and vibratory, we suggest that rotatory energy dominates in liquids. 展开更多
关键词 liquid Phase Even-Odd Rule Molecular Stability Specific Periodic Table Saturation UNSATURATED Rotational Energy Angular Kinetic Energy
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Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle
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作者 Wei-li Wu Chang-gui Cheng +2 位作者 Yang Li Shi-fa Wei De-li Chen 《China Foundry》 SCIE EI CAS CSCD 2024年第2期185-196,共12页
In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In ord... In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT software.Results show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either side.As the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes uneven.Although increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction. 展开更多
关键词 continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate
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Transient liquid phase bonding of DD5 superalloy using a designed interlayer: microstructure and mechanical properties
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作者 周昌杰 范骁乐 +3 位作者 朱立华 陈闯 贺建超 计红军 《China Welding》 CAS 2024年第2期1-10,共10页
Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmen... Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmental service are inevitable challenges for turbine blades.Therefore,bonding techniques play a very important role in the manufacturing and repair of turbine blades.The transient liquid phase(TLP)bonding of DD5 Ni-based single crystal superalloy was performed using the designed H1 interlayer.A new third-generation Ni-based superalloy T1 powder was mixed with H1 powder as another interlayer to improve the mechanical properties of the bonded joints.The res-ults show that,such a designed H1 interlayer is beneficial to the improvement of shear strength of DD5 alloy bonded joints by adjusting the bonding temperature and the prolongation of holding time.The maximum shear strength at room temperature of the joint with H1 interlayer reached 681 MPa when bonded at 1260℃for 3 h.The addition of T1 powder can effectively reduce holding time or relatively lower bond-ing temperature,while maintaining relatively high shear strength.When 1 wt.%T1 powder was mixed into H1 interlayer,the maximum room temperature shear strength of the joint bonded at 1260℃reached 641 MPa,which could be obtained for only 1 h.Considering the bonding temperature and the efficiency,the acceptable process parameter of H1+5 wt.%T1 interlayer was 1240℃/2 h,and the room tem-perature shear strength reached 613 MPa. 展开更多
关键词 Ni-based superalloy powder transient liquid phase bonded joint shear strength
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Liquid–liquid phase transition in confined liquid titanium
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作者 张迪 段云瑞 +6 位作者 郑培儒 马英杰 钱俊平 李志超 黄建 蒋妍彦 李辉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期391-398,共8页
We report the layering and liquid–liquid phase transition of liquid titanium confined between two parallel panel walls.Abnormal changes in the volume and the potential energy confirm the existence of the liquid–liqu... We report the layering and liquid–liquid phase transition of liquid titanium confined between two parallel panel walls.Abnormal changes in the volume and the potential energy confirm the existence of the liquid–liquid phase transition of the liquid titanium. The typical feature of the liquid–liquid phase transition is layering, which is induced by the slit size,pressure and temperature. We highlight the fact that the slit size and pressure will determine the number of layers. In addition, with the change in the slit size, the density of the confined liquid expresses a fluctuating law. The phase diagram of the layering transition is drawn to clearly understand the layering. This study provides insights into the liquid–liquid phase transition of liquid metal in a confined space. 展开更多
关键词 TITANIUM layering transition liquidliquid phase transition confined space
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Understanding the catalytic performance and deactivation behaviour of second-promoter doped Pt/WO_(χ)/γ-Al_(2)O_(3) catalysts in the glycerol hydrogenolysis for selective and cleaner production of 1,3-propanediol
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作者 Rafik Rajjak Shaikh Sittichai Damruang +2 位作者 Rais Ahmad Khan Supareak Praserthdam Piyasan Praserthdam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期486-507,共22页
The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the ca... The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the catalyst deactivation via sintering,metal leaching,and coking can predominantly occur in the aqueous phase reaction.In this work,the effect of reaction temperature,pressure and second promoter(Cu,Fe,Rh,Mn,Re,Ru,Ir,Sn,B,and P)on catalytic performance and deactivation behaviour of Pt/WOx/-Al2O3 was investigated.When doped with Rh,Mn,Re,Ru,Ir,B,and P,the second promoter boosts catalytic activity by promoting great dispersion of Pt on support and increasing Pt surface area.The increased Bronsted acid sites lead to selective synthesis of 1,3-PDO than 1,2-propanediol(1,2-PDO).The characterization studies of fresh and spent catalysts reveal that the main cause of catalyst deactivation is the Pt sintering,as interpreted based on XRD,CO chemisorption,and TEM analyses.The Pt sintering is affected depending on the second promoter that can either or reduce the interaction between Pt,WO_(χ)/γ and Al_(2)O_(3).As an electron acceptor of Pt in Pt/WO_(χ)/γ-Al_(2)O_(3),Re and Mn as second promoters resulted in increased Pt^(2+) on the catalytic surface,which strengthens the contact between Pt andγ-Al_(2)O_(3) and WO_(χ),resulting in a decrease in Pt sintering.The metal leaching and coking are not affected by the presence of second promoter.The catalyst modified with a second promoter possesses improved catalytic activity and 1,3-PDO production,however the stability continues to remain a challenge.The present work unrav-elled the determining parameters of catalytic activity and deactivation,thus providing a promising pro-tocol toward effective catalysts for glycerol hydrogenolysis. 展开更多
关键词 Glycerol hydrogenolysis 1 3-PROPANEDIOL Metal-support interaction Second promoter liquid phase Catalyst deactivation
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Kinetic characteristics of liquid phase sintering of mechanically activated W-15wt%Cu powder 被引量:7
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作者 Zhigang Li Chengchang Jia Yuntao He Liliang Chen 《Journal of University of Science and Technology Beijing》 CSCD 2006年第4期338-345,共8页
The kinetic characteristics of W grain growth operated by diffusion controlled Oswald ripening (DOR) during liquid phase sintering were studied. A liquid phase sintering of W-15wt%Cu was carried out by pushing compa... The kinetic characteristics of W grain growth operated by diffusion controlled Oswald ripening (DOR) during liquid phase sintering were studied. A liquid phase sintering of W-15wt%Cu was carried out by pushing compacts into a furnace at the moment when the temperature increased to 1340℃ for different sintering times. The results show that liquid phase sintering produces the compacts with considerably low relative density and inversely, rather high homogeneity. On the basis of the data extracted from the SEM images, the kinetic equation of W grain growth, G^n = G0^n + kt, is determined in which the grain growth exponent n is 3 and the grain growth rate constant k is 0.15 μm^3/s. The cumulative normalized grain size distributions produced by different sintering times show self-similar. The cumulative distribution function is extracted from the curves by non-linear fitting. In addition, the sintering kinetic characteristics of W-15wt%Cu compacts were also investigated. 展开更多
关键词 liquid phase sintering mechanical alloying grain growth kinetics W-Cu alloy
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RESEARCH ON METHOD TO CALCULATE VELOCITIES OF SOLID PHASE AND LIQUID PHASE IN DEBRIS FLOW 被引量:4
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作者 陈洪凯 唐红梅 陈野鹰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第3期399-408,共10页
Velocities of solid phase and liquid phase in debris flow are one key problem to research on impact and abrasion mechanism of banks and control structures under action of debris flow. Debris flow was simplified as two... Velocities of solid phase and liquid phase in debris flow are one key problem to research on impact and abrasion mechanism of banks and control structures under action of debris flow. Debris flow was simplified as two-phase liquid composed of solid phase with the same diameter particles and liquid phase with the same mechanical features. Assume debris flow was one-dimension two-phase liquid moving to one direction, then general equations of velocities of solid phase and liquid phase were founded in two-phase theory. Methods to calculate average pressures, volume forces and surface forces of debris flow control volume were established. Specially, surface forces were ascertained using Bingham's rheology equation of liquid phase and Bagnold's testing results about interaction between particles of solid phase. Proportional coefficient of velocities between liquid phase and solid phase was put forward, meanwhile, divergent coefficient between theoretical velocity and real velocity of solid phase was provided too. To state succinctly before, method to calculate velocities of solid phase and liquid phase was obtained through solution to general equations. The method is suitable for both viscous debris flow and thin debris flow. Additionally, velocities every phase can be identified through analyzing deposits in-situ after occurring of debris flow. It is obvious from engineering case the result in the method is consistent to that in real-time field observation. 展开更多
关键词 debris flow two-phase fluid velocities of solid phase and liquid phase calculation method VERIFICATION
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Influence of gangue existing states in iron ores on the formation and flow of liquid phase during sintering 被引量:3
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作者 Guo-liang Zhang Sheng-li Wu +3 位作者 Shao-guo Chen Bo Su Zhi-gang Que Chao-gang Hou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第10期962-968,共7页
Gangue existing states largely affect the high-temperature characteristics of iron ores. Using a micro-sintering method and scan- ning electron microscopy, the effects of gangue content, gangue type, and gangue size o... Gangue existing states largely affect the high-temperature characteristics of iron ores. Using a micro-sintering method and scan- ning electron microscopy, the effects of gangue content, gangue type, and gangue size on the assimilation characteristics and fluidity of liquid phase of five different iron ores were analyzed in this study. Next, the mechanism based on the reaction between gangues and sintering mate- dais was unraveled. The results show that, as the SiO2 levels increase in the iron ores, the lowest assimilation temperature (LAT) decreases, whereas the index of fluidity of liquid phase (IFL) increases. Below 1.5wt%, Al2O3 benefits the assimilation reaction, but higher concentra- tions proved detrimental. Larger quartz particles increase the SiO2 levels at the local reaction interface between the iron ore and CaO, thereby reducing the LAT. Quartz-gibbsite is more conductive to assimilation than kaolin. Quartz-gibbsite and kaolin gangues encourage the forma- tion of liquid-phase low-Al2O3-SFCA with high IFL and high-Al2O3-SFCA with low IFL, respectively. 展开更多
关键词 iron ores ore sintering ASSIMILATION liquid phase FLUIDITY
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Enhancement of Sensitivity for Determination of Phenols in Environmental Water Samples by Single-drop Liquid Phase Microextraction Using Ionic Liquid prior to HPLC 被引量:5
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作者 Qing Xiang ZHOU Jun Ping XIAO +1 位作者 Cun Ling YE Xin Ming WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1073-1076,共4页
A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) was demonstrated for the sensitive determination of four phenols in water samples. Under the... A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) was demonstrated for the sensitive determination of four phenols in water samples. Under the optimized conditions, the linear range of proposed method was excellent in the range of 0.5-100 μg·L^-1, the reproducibility (RSD, n=6) were in the range 5.4%-8.9% and detection limits (S/N=3) were 0.3, 0.3, 0.5 and 0.5 μg·L^-1 for 2, 4-dichlorophenol, 2-naphthol, 2-nitrophenol and 4-chlorophenol, respectively. The experimental results indicated that the effect of complex matrices natural water samples could be resolved with addition of sodium ethylene diamine tetracetate (EDTA) into the samples. Excellent spiked recoveries were achieved for these four phenols ranged from 86.2%-114.9 %. All these facts demonstrated that the proposed method with merits of low cost, simplicity and easy operating would be a competitive alternative procedure for the determination of such compounds at trace level. 展开更多
关键词 1-Butyl-3-methylimidazolium hexafluorophosphate single-drop liquid phase microextraction phenols.
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Liquid phase epitaxy magnetic garnet films and their applications 被引量:3
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作者 饶毅恒 张怀武 +4 位作者 杨青慧 张岱南 金立川 马博 吴玉娟 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期62-71,共10页
Liquid phase epitaxy (LPE) is a mature technology. Early experiments on single magnetic crystal films fabricated by LPE were focused mainly on thick films for microwave and magneto-optical devices. The LPE is an exc... Liquid phase epitaxy (LPE) is a mature technology. Early experiments on single magnetic crystal films fabricated by LPE were focused mainly on thick films for microwave and magneto-optical devices. The LPE is an excellent way to make a thick film, low damping magnetic garnet film and high-quality magneto-optical material. Today, the principal challenge in the applied material is to create sub-micrometer devices by using modern photolithography technique. Until now the magnetic garnet films fabricated by LPE still show the best quality even on a nanoscale (about 100 nm), which was considered to be impossible for LPE method. 展开更多
关键词 liquid phase epitaxy (LPE) magnetic garnet MAGNETO-OPTICAL SPINTRONICS magnonics
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Growth and characteristics of InAsSb epilayers with a cutoff wavelength of 4.8 μm prepared by one-step liquid phase epitaxy 被引量:3
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作者 GAO Yuzhu GONG Xiuying +1 位作者 FANG Weizheng Akihiro Ishida 《Rare Metals》 SCIE EI CAS CSCD 2009年第4期313-316,共4页
InAsSb epilayers with a cutoff wavelength of 4.8 μm have been successfully grown on InAs substrates by one-step liquid phase epitaxy (LPE) technology. The epilayers were characterized by X-ray diffraction (XRD), ... InAsSb epilayers with a cutoff wavelength of 4.8 μm have been successfully grown on InAs substrates by one-step liquid phase epitaxy (LPE) technology. The epilayers were characterized by X-ray diffraction (XRD), Fourier transform infrared (PTIR) transmittance measurements and scanning electron microscopy (SEM). The influence of different growth conditions on the optical and structural properties of the materials was studied. The results revealed that the good crystalline quality, mirror smooth surface and flat interface of InAsSb epilayers were achieved. They benefited from optimized growth conditions, i.e., sufficient homogeneity of the growth melt and a very slow cooling rate. 展开更多
关键词 INASSB liquid phase epitaxy crystalline quality cutoff wavelength scanning electron microscopy
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A two-step transient liquid phase diffusion bonding process of T91 steels 被引量:4
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作者 陈思杰 唐恒娟 赵丕锋 《China Welding》 EI CAS 2017年第2期52-57,共6页
In this study, a two-step heating process is introduced for transient liquid phase ( TLP) diffusion bonding fo r sound joints with T91 heat resistant steels. At first, a short-time higher temperature heatin... In this study, a two-step heating process is introduced for transient liquid phase ( TLP) diffusion bonding fo r sound joints with T91 heat resistant steels. At first, a short-time higher temperature heating step is addressed to melt the interlayer, followed by the second step to complete isothermal solidification at a low temperature. The most critical feature of our new method is producing a non-planar interface at the T9/ heat resistant steels joint. We propose a transitional liquid phase bonding of T91 heat resistant steels by this approach. Since joint microstructures have been studied, we tested the tensile strength to assess joint mechanical property. The result indicates that the solidified bond may contain a primary solid-solution, similar composition to the parent metal and free from precipitates. Joint tensile strength of the joint is not lower than parent materials. Joint bend's strengths are enhanced due to the higher metal-to-metal junction producing a non-planar bond lines. Nevertheless, the traditional transient liquid phase diffusion bonding produces planar ones. Bonding parameters of new process are 1 260 °C for 0. 5 min and 1 230 °C fo r 4 min. 展开更多
关键词 T91 transient liquid phase diffusion bonding two-step heating process scanning electron microscopy
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Dynamic microwave-assisted extraction combined with liquid phase microextraction based on the solidification of a floating drop for the analysis of organochlorine pesticides in grains followed by GC 被引量:4
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作者 Guijie Li Xu Zhang +5 位作者 Tingting Liu Hongxiu Fan Hongcheng Liu Shangyu Li Dawei Wang Lan Ding 《Food Science and Human Wellness》 SCIE 2021年第3期375-382,共8页
A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides... A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides in grains including rice,maize and millet.Twelve samples can be processed simultaneously in the method.During the extraction process,10%acetonitrile-water solutions containing 110μL of n-hexadecane were used to extract organochlorine pesticides.Subsequently,1.0 g sodium chloride was placed in the extract,and then centrifuged and cooled.The n-hexadecane drops containing the analytes were solidifi ed and transferred for determination by gas chromatography-electron capture detector without any further filtration or cleaning process.Limits of detection for organochlorine pesticides were 0.97–1.01μg/kg and the RSDs were in the range of 2.6%–8.5%.The developed technology has succeeded in analyzing six real grains samples and the recoveries of the organochlorine pesticides were 72.2%–94.3%.Compared with the published extraction methods,the developed method was used to analyze organochlorine pesticides in grains,being more environmentally friendly,which is suitable for the daily determination of organochlorine pesticides. 展开更多
关键词 Dynamic microwave-assisted extraction liquid phase microextraction Gas chromatography Organochlorine pesticides Grain
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Features of microstructure and fracture in the transient liquid phase bonded aluminium-based metal matrix composite joints 被引量:3
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作者 孙大谦 刘卫红 +2 位作者 吴建红 贾树盛 邱小明 《China Welding》 EI CAS 2002年第1期9-13,共5页
Transient liquid phase (TLP) bonded aluminium based metal matrix composite (MMC) joints can be classified into three distinct regions, i.e. the particulate segregation region, the denuded particulate region and the ... Transient liquid phase (TLP) bonded aluminium based metal matrix composite (MMC) joints can be classified into three distinct regions, i.e. the particulate segregation region, the denuded particulate region and the base material region. The microstructure of the particulate segregation region consists of alumina particulate and Al alloy matrix with the Al 2Cu and MgAl 2O 4. It contains more and smaller alumina particulates compared with the base material region. The TLP bonded joints have the tensile strength of 150 MPa ~200 MPa and the shear strength of 70 MPa ~100 MPa . With increasing tensile stress, cracks initiate in the particulate segregation region, especially in the particulate/particulate interface and the particulate/matrix interface, and propagate along particulate/matrix interface, througth thin matrix metal and by linking up the close cracks. The particulate segregation region is the weakest during tensile testing and shear testing due to obviously increased proportion of weak bonds (particulate particulate bond and particulate matrix bond). 展开更多
关键词 aluminium based metal matrix composite transient liquid phase bonding MICROSTRUCTURE FRACTURE
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Effects of Ni addition on liquid phase separation and giant magnetoresistance of Cu-Co alloys 被引量:2
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作者 孙占波 宋晓平 +4 位作者 胡柱东 祝要民 刘剑 杨森 李晓园 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期655-658,共4页
The effects of Ni addition on the liquid phase separation and giant magnetoresi stance (GMR) of Cu Co alloys were discussed. The results reveal that Ni additio n can partially restrain the liquid phase separation of C... The effects of Ni addition on the liquid phase separation and giant magnetoresi stance (GMR) of Cu Co alloys were discussed. The results reveal that Ni additio n can partially restrain the liquid phase separation of Cu Co alloys, resultin g in a decrease of volume fraction for the Co rich particles separated from the liquid phase and in refined microstructures. The composition analyses indicate t hat Ni is dissolved in both the Co rich and the Cu rich phases, but Ni content in the Co rich phase is much higher than that in the Cu matrix. At the same ti me, Ni addition enhance the solubility between Cu and Co, especially Cu in Co s olid solution. Ni alloying into Cu Co alloys can fully prevent the liquid phase separation during melt spinning, which is very beneficial to improve GMR of Cu Co alloys. 展开更多
关键词 Cu Co Ni alloys SUPERCOOLING melt spun liquid phase separation microstruc ture GMR
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Modeling Non-aqueous Phase Liquid Displacement Process 被引量:2
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作者 Yang Zhenqing Shao Changjin Zhou Guanggang Qiu Chao 《Petroleum Science》 SCIE CAS CSCD 2007年第3期40-46,共7页
A pore-network model physically based on pore level multiphase flow was used to study the water-non-aqueous phase liquid (NAPL) displacement process, especially the effects of wettability, water-NAPL interracial ten... A pore-network model physically based on pore level multiphase flow was used to study the water-non-aqueous phase liquid (NAPL) displacement process, especially the effects of wettability, water-NAPL interracial tension, the fraction of NAPL-wet pores, and initial water saturation on the displacement. The computed data show that with the wettability of the mineral surfaces changing from strongly water-wet to NAPL-wet, capillary pressure and the NAPL relative permeability gradually decrease, while water-NAPL interfacial tension has little effect on water relative permeability, but initial water saturation has a strong effect on water and NAPL relative permeabilities. The analytical results may help to understand the micro-structure displacement process of non-aqueous phase liquid and to provide the theoretical basis for controlling NAPL migration. 展开更多
关键词 Non-aqueous phase liquid pore-network model capillary pressure relative permeability
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Liquid-phase epoxidation of propylene with molecular oxygen by chloride manganese meso-tetraphenylporphyrins 被引量:1
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作者 Xian-Tai Zhou Ling-Ling Wang +1 位作者 Yang Li Hong-Bing Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第8期61-65,共5页
Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of selectivity.In this work,the direct liquid-phase propylene aerobic epoxidation pro... Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of selectivity.In this work,the direct liquid-phase propylene aerobic epoxidation protocol by chloride manganese meso-tetraphenylporphyrin(MnTPPCl)was developed.The conversion of propylene was 12.7%,and the selectivity towards PO(propylene oxide)reached up to 80.5%.The formation of PO was attributed to the mechanism via high-valent Mn species,which was confirmed by means of in situ UV–vis spectrum. 展开更多
关键词 PROPYLENE EPOXIDATION DIOXYGEN Manganese porphyrins liquid phase
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Replacement of annular domain with trapezoidal domain in computational modeling of nonaqueous-phase-liquid dissolution-front propagation problems 被引量:2
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作者 赵崇斌 Thomas POULET Klaus REGENAUER-LIEB 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1841-1846,共6页
In order to simulate the instability phenomenon of a nonaqueous phase liquid(NAPL) dissolution front in a computational model, the intrinsic characteristic length is commonly used to determine the length scale at whic... In order to simulate the instability phenomenon of a nonaqueous phase liquid(NAPL) dissolution front in a computational model, the intrinsic characteristic length is commonly used to determine the length scale at which the instability of the NAPL dissolution front can be initiated. This will require a huge number of finite elements if a whole NAPL dissolution system is simulated in the computational model. Even though modern supercomputers might be used to tackle this kind of NAPL dissolution problem, it can become prohibitive for commonly-used personal computers to do so. The main purpose of this work is to investigate whether or not the whole NAPL dissolution system of an annular domain can be replaced by a trapezoidal domain, so as to greatly reduce the requirements for computer efforts. The related simulation results have demonstrated that when the NAPL dissolution system under consideration is in a subcritical state, if the dissolution pattern around the entrance of an annulus domain is of interest, then a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution system.However, if the dissolution pattern away from the vicinity of the entrance of an annulus domain is of interest, then a trapezoidal domain can be used to replace an annular domain in the computational simulation of the NAPL dissolution system. When the NAPL dissolution system under consideration is in a supercritical state, a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution system. 展开更多
关键词 nonaqueous phase liquid(NAPL) trapezoidal domain computational simulation dissolution front instability
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Liquid Phase Behavior during Elevated Temperature Deformation of the Fine-Grained 5083 Al Alloy 被引量:1
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作者 Honghua Yan Kaifeng Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第5期673-676,共4页
The liquid phase behavior of the fine-grained 5083 AI alloy obtained through thermomechanical process was investigated during the tensile tests in a temperature range of 380-570℃ and strain rate range of 4.17× 1... The liquid phase behavior of the fine-grained 5083 AI alloy obtained through thermomechanical process was investigated during the tensile tests in a temperature range of 380-570℃ and strain rate range of 4.17× 10^-4- 1.0× 10^-2 s^-1. The maximum elongation 530% of the fine-grained 5083 AI alloy was obtained at 550℃ and 4.17× 10^-4 s^-1. Fracture analysis by scanning electron microscopy (SEM) indicated that the formation of filament (formed by liquid phase) was greatly affected by the tensile temperature and strain rate. The results also showed that the optimum morphology of formed filament was obtained at 550℃ and a strain rate of 4.17× 10^-4 s^-1. The effect of liquid phase on superplastic deformation of the alloy was further discussed. 展开更多
关键词 Thermomechanical process Fine-graied 5083 Al alloy liquid phase SUPERPLASTICITY
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Liquid Phase Catalytic Oxidation of Low-Concentration H_2S in Cerium Doped Absorption Solution 被引量:1
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作者 易红宏 唐晓龙 +1 位作者 宁平 于丽丽 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期253-256,共4页
For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified ... For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified well by liquid phase catalytic oxidation (LCO), and the sulfur resource could also be recovered. The absorption solution was prepared by FeCl3 and sulfosalicylic acid. Under the experimental conditions, the conversion of H2S to S could be maintained above 94% at 60 ℃. In order to enhance the economical efficiency of LCO method, the absorption solution was modified by doping Ce, and a series of experiments were designed to investigate its performance. The results showed that the conversion of H2S had no obvious improvement, but above 98% conversion could be gained at 60 ℃, and the H2S conversion rate was enhanced. The optimum addition quality of Ce(NO3)3 was 0.08 g to 50 ml Fe3+ solution. 展开更多
关键词 hydrogen sulfide liquid phase catalytic oxidation CERIUM rare earths
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