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Development and Performance Evaluation of Catalyst for Productive Ethylene Cracking Feedstock in Selective Hydrocracking of Straight Run Diesel Oil
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作者 Tiezhen Zhang Xin Zhang +5 位作者 Yungang Jia Haiyan Li Fangming Xie Zijin Yan Hongyu Tian Hongyu Zhang 《Open Journal of Applied Sciences》 CAS 2023年第3期414-423,共10页
The upgrading of diesel oil to produce ethylene rich cracking feedstock is an important and promising technical route to reduce the ratio of diesel to gasoline. In the present work, a hydrocracking catalyst suitable f... The upgrading of diesel oil to produce ethylene rich cracking feedstock is an important and promising technical route to reduce the ratio of diesel to gasoline. In the present work, a hydrocracking catalyst suitable for selective hydrocracking of straight run diesel oil to produce high-quality ethylene cracking feedstock at low cost was developed, by optimizing the composition of catalyst support materials, using amorphous silicon aluminum and aluminum oxide with high mesopore content as the main support, and modified Y zeolite with excellent aromatic ring opening selectivity as the acidic component. The catalyst has in-depth characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, N<sub>2</sub>-low temperature adsorption-desorption, NH<sub>3</sub>-temperature-programmed desorption, and IR techniques. And its catalytic cracking straight run diesel oil performance was evaluated. The results show that the prepared catalyst has high polycyclic aromatic hydrocarbon ring opening cracking selectivity. However, alkanes retained in diesel distillates can achieve the goal of producing more ethylene cracking feedstocks with low BMCI value under low and moderate pressure conditions. This work may shed significant technical insight for oil refining transformation. 展开更多
关键词 Straight Run Diesel Mild Hydrocracking CATALYST Ethylene Cracking feedstock Process Research
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Improvement to Maize Growth Caused by Biochars Derived From Six Feedstocks Prepared at Three Different Temperatures 被引量:9
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作者 LUO Yu JIAO Yu-jie +3 位作者 ZHAO Xiao-rong LI Gui-tong ZHAO Li-xin MENG Hai-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期533-540,共8页
Biochar is increasingly proposed as a soil amendment, with reports of benefits to soil physical, chemical and biological properties. In this study, different biochars were produced from 6 feedstocks, including straw a... Biochar is increasingly proposed as a soil amendment, with reports of benefits to soil physical, chemical and biological properties. In this study, different biochars were produced from 6 feedstocks, including straw and poultry manure, at 3 pyrolysis temperatures (200, 300 and 500℃) and then added separately to a calcareous soil. Their effects on soil properties and maize growth were evaluated in a pot experiment. The biochars derived from crop straw had much higher C but smaller N concentrations than those derived from poultry manure. Carbon concentrations, pH and EC values increased with increasing pyrolysis temperature. Biochar addition resulted in increases in mean maize dry matter of 12.73% and NPK concentrations of 30, 33 and 283%, respectively. Mean soil pH values were increased by 0.45 units. The biochar-amended soils had 44, 55, 254 and 537% more organic C, total N, Olsen-P and available K, respectively, than the control on average. Both feedstocks and pyrolysis temperature determined the characteristics of the biochar. Biochars with high mineral concentrations may act as mineral nutrient supplements. 展开更多
关键词 BIOCHAR feedstock temperature MAIZE soil
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Synthesis of nanocrystalline NiCrC alloy feedstock powders for thermal spraying by cryogenic ball milling 被引量:3
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作者 Kai Tao Xiang-lin Zhou +3 位作者 Hua Cui Han-bin Chen Yong-bing Li Ji-shan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第1期77-83,共7页
Nanocrystalline NiCrC alloy powders with a qualified particle size distribution for thermal spraying were synthesized using the cryogenic ball milling (cryomilling) method. The morphology, microstructure, size distr... Nanocrystalline NiCrC alloy powders with a qualified particle size distribution for thermal spraying were synthesized using the cryogenic ball milling (cryomilling) method. The morphology, microstructure, size distribution, and phase transformation of the powders were characterized by scanning electron microscopy (SEM), laser scattering for particle size analysis, X-ray diffraction (XRD), and transmission electron microscopy (TEM). After cryomilling for 20 h, the average grain size of the as-milled powders approached a constant value of 30 nm by XRD measurement. The average particle size slightly increased from 17.5 to 20.3 μm during the 20-h milling. About 90vol% of the powders satisfied the requirement for thermal spraying with the particle dimension of 10-50 μm, and most of the powders exhibited spherical morphology, which were expected to have good fluidity during thermal spraying. The Cr2O3 phase formed during the cryornilling process as revealed in the XRD spectra, which was expected to enhance the thermal stability of the as-milled powders during the followed thermal spraying or other heat treatment. 展开更多
关键词 CRYOMILLING NANOCRYSTALLINE feedstock powder particle size distribution nickel chromium alloy
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Two Types of Novel Feedstock Injection Structures of the FCC Riser Reactor 被引量:4
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作者 范怡平 蔡飞鹏 +1 位作者 时铭显 徐春明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期42-48,共7页
Based on the analysis of flow characteristics of the FCC riser feedstock injection zone, two novel feedstock injection structures are put forward. By investigating three flow parameters in the feedstock injection zone... Based on the analysis of flow characteristics of the FCC riser feedstock injection zone, two novel feedstock injection structures are put forward. By investigating three flow parameters in the feedstock injection zone under the three different structures (the traditional and the novel No. 1, No. 2 structures): the local density, the particle backmixng ratio, and the jet eigen-concentration, the flow feature under three structures were obtained. The experimental results demonstrate that the flow features under both proposed structures are obviously improved comparing with those under the traditional structure. Especially, the performance of the deflector-structured No. 2 is more desirable than that of No. 1. 展开更多
关键词 FCC riser reactor feedstock injection STRUCTURE
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RHEOLOGICAL PROPERTIES OF METAL INVECTION MOLDING BINDER AND FEEDSTOCK 被引量:2
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作者 Li, YM Qu, XH +1 位作者 Huang, BY Qiu, GH 《中国有色金属学会会刊:英文版》 CSCD 1997年第3期104-108,共5页
RHEOLOGICALPROPERTIESOFMETALINVECTIONMOLDINGBINDERANDFEEDSTOCK①LiYimin,QuXuanhui,HuangBaiyun,QiuGuanghanNati... RHEOLOGICALPROPERTIESOFMETALINVECTIONMOLDINGBINDERANDFEEDSTOCK①LiYimin,QuXuanhui,HuangBaiyun,QiuGuanghanNationalKeyLaboratory... 展开更多
关键词 METAL injection MOLDING feedstock BINDER VISCOSITY
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Rheological properties of feedstocks for powder extrusion molding 被引量:1
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作者 周继承 黄伯云 吴恩熙 《中国有色金属学会会刊:英文版》 CSCD 2000年第5期639-641,共3页
The rheological behaviors of feedstocks for powder extrusion molding, in the temperature range of 40~80 ℃ and the Newton shear rate of 3~800 s -1 , were studied. The effects of feedstock constitution, shear rate an... The rheological behaviors of feedstocks for powder extrusion molding, in the temperature range of 40~80 ℃ and the Newton shear rate of 3~800 s -1 , were studied. The effects of feedstock constitution, shear rate and temperature on apparent viscosity, shear stress and active energy were investigated. The viscose flow active energy of PEM feedstocks is 15.89~90.77 kJ/mol. Based on this research, the PEM technical parameters have optimized. [ 展开更多
关键词 POWDER EXTRUSION MOLDING feedstock RHEOLOGICAL property apparent viscosity
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DEBINDING MECHANISM AND KINETICS FOR PW IN PW-WC FEEDSTOCK UNDER AIR ATMOSPHERE 被引量:1
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作者 Liang Shuquan Huang Baiyun Qu Xuanhui (National Laboratory for Powder Metallurgy ,Central South University of Technology, Changsha 410083) 《中国有色金属学会会刊:英文版》 CSCD 1996年第2期72-75,共4页
DEBINDINGMECHANISMANDKINETICSFORPWINPW-WCFEEDSTOCKUNDERAIRATMOSPHERELiangShuquan;HuangBaiyun;QuXuanhui(Natio... DEBINDINGMECHANISMANDKINETICSFORPWINPW-WCFEEDSTOCKUNDERAIRATMOSPHERELiangShuquan;HuangBaiyun;QuXuanhui(NationalLaboratoryforP... 展开更多
关键词 MIM PW-WC feedstock DEBINDING process mechanism KINETICS
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Comparison of Potential Bio-Energy Feedstock Production and Water Quality Impacts Using a Modeling Approach 被引量:1
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作者 Prem B. Parajuli 《Journal of Water Resource and Protection》 2012年第9期763-771,共9页
Cellulosic and agricultural bio-energy crops can be utilized as feedstock source for bio-fuels production and provide environmental benefits such as hydrology, water quality. This study compared potential feedstock yi... Cellulosic and agricultural bio-energy crops can be utilized as feedstock source for bio-fuels production and provide environmental benefits such as hydrology, water quality. This study compared potential feedstock yield and water quality benefit scenarios of six bio-energy crops: Miscanthus (Miscanthus-giganteus), Switchgrass (Panicum virgatum), Johnsongrass (Sorghum halepense), Alfalfa (Medicago sativa L.), Corn (Zea mays), and Soybean {Glycine max (L.) Merr.} at the watershed scale using Soil and Water Assessment Tool (SWAT) model. The SWAT model was calibrated (1998 to 2002) and validated (2003 to 2010) using monthly measured USGS stream flow data. Model was further verified using available monthly sediment yield, and county level NASS corn and soybean yield data within the watershed. The long-term average annual potential feedstock yield as an alternative energy source was determined the greatest when growing Miscanthus grass scenario (21.9 Mg/ha) followed by Switchgrass (15.2 Mg/ha), Johnsongrass (12.1 Mg/ha), Alfalfa (7 Mg/ha), Corn (5.9 Mg/ha), and Soybean (2.35 Mg/ha). Model results determined the least amount of average annual sediment yield (1.1 Mg/ha) from the Miscanthus grass scenario and the greatest amount (12 Mg/ha) from the corn crop scenario. About 11% less annual average surface water flow from the watershed could be anticipated when converting land areas from soybean to Miscanthus grass. The results of this study suggested that growing Miscanthus grass in the UPRW would have the greatest potential feedstock yield and water quality benefits. The results of this study may help in developing future watershed management programs. 展开更多
关键词 Biofuels feedstock Yield STREAM Flow Water Quality SWAT WATERSHED
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Microbial production of L-malate from renewable non-food feedstocks 被引量:1
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作者 Youming Jiang Xiaohan Ye +4 位作者 Tianwen Zheng Weiliang Dong Fengxue Xin Jiangfeng Ma Min Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期105-111,共7页
L-malate is an intermediate of the tricarboxylic acid cycle which is naturally occurred in various microorganisms,and it has been widely applied in polymer,beverage and food,textile,agricultural and pharmaceutical ind... L-malate is an intermediate of the tricarboxylic acid cycle which is naturally occurred in various microorganisms,and it has been widely applied in polymer,beverage and food,textile,agricultural and pharmaceutical industries.Driven by the pursuit of a sustainable economy,microbial production of L-malate has received much attention in last decades.In this review,we focus on the utilization of wastes and/or byproducts as feedstocks for the microbial production of L-malate.Firstly,we present the recent developments on the natural or engineered metabolic pathways that dedicate to the biosynthesis of L-malate,and also provide a comprehensive discussions on developing high-efficient producers.Then,the recent achievements in microbial production of L-malate from various carbon sources were concluded and discussed.Furthermore,some abundant non-food feedstocks which have been used for microbial production of other chemicals were reviewed,as they may be potential candidate feedstock for L-malate production in future.Finally,we outlined the major challenges and proposed further improvements for the production of L-malate. 展开更多
关键词 L-MALATE Renewable feedstock Microbial fermentation BIOECONOMY C4 dicarboxylic acid
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Row Spacing Affects Biomass Yield and Composition of Kenaf (<i>Hibiscus cannabinus</i>L.) as a Lignocellulosic Feedstock for Bioenergy 被引量:2
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作者 Marisol T. Berti Srinivas Reddy Kamireddy Yun Ji 《Journal of Sustainable Bioenergy Systems》 2013年第1期68-73,共6页
Kenaf (Hibiscus cannabinus L.) is a warm-season annual. Kenaf fibers are commonly used for paper pulp and cordage, but it is also a promising lignocellulosic feedstock for bioenergy production, although optimum plant ... Kenaf (Hibiscus cannabinus L.) is a warm-season annual. Kenaf fibers are commonly used for paper pulp and cordage, but it is also a promising lignocellulosic feedstock for bioenergy production, although optimum plant density for biomass production has not been determined for the northern region of the USA. The objective of this study was to determine the best plant density and row spacing of kenaf to maximize biomass yield and chemical composition for biofuel conversion. The experiments were conducted at Fargo and Prosper, ND, in 2010 and 2011. The experiment was a randomized complete block design with a split-plot arrangement where the main plot was tworowspacings (30 and60 cm) and the sub-plot fourplant densities (32, 16, 8, and 4 plants·m-2). Row spacing had a significant effect on both biomass and biofuel yield. Narrower rows had higher biomass and biofuel yield. Maximum biomass and estimated biofuel yield was obtained with the two highest plant densities of 16 and 32 plants·m-2 and fluctuated between 9.45 and 10.22 Mg·ha-1 and 1354 and1464 L·ha-1, respectively. Stem diameter increased with a decrease in plant density. Chemical composition varied with plant density;glucan (27%) and xylan (9.8%) content were lower at the lowest plant density. Ash content was not different among plant densities but it is interesting to mention the very low ash content of kenaf (0.15%). According to the results of this study, it is recommended to plant kenaf at 30-cm rows with a plant density of 16 to 32 plants·m-2 to maximize biomass yield. Kenaf has a tremendous potential as a cellulosic feedstock for biofuel and green chemicals in the Northern Great Plains because of high biomass yield and low ash content. 展开更多
关键词 BIOENERGY LIGNOCELLULOSIC feedstock Plant Density GLUCANS XYLANS Ash
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Renewable Hydrogen Produced from Different Renewable Feedstock by Aqueous-Phase Reforming Process 被引量:1
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作者 Yi Wei Hanwu Lei +6 位作者 Yupeng Liu Lu Wang Lei Zhu Xuesong Zhang Gayatri Yadavalli Birgitte Ahring Shulin Chen 《Journal of Sustainable Bioenergy Systems》 2014年第2期113-127,共15页
Aqueous phase reforming (APR) of biomass derived feedstock producing hydrogen was reviewed. The APR process was discussed based on different feedstock categories such as sugars, polyols and ethanol. The mechanism of A... Aqueous phase reforming (APR) of biomass derived feedstock producing hydrogen was reviewed. The APR process was discussed based on different feedstock categories such as sugars, polyols and ethanol. The mechanism of APR was analyzed referring to different structures of feedstock. The reaction pathways of APR were investigated. The usage of catalysts should be judged by feedstock on the requirement including C-C bond cleavage, water-gas shift (WGS) reaction, and catalyst maintenance. The prospects were concluded based on the recent works from bimetallic catalysts and high efficient supports. Examples of significant challenges of reducing catalyst cost and increasing catalyst stability have been discussed. The modification and utilization of alkane selectivity of APR processes for liquid fuel production was also investigated. 展开更多
关键词 AQUEOUS Phase REFORMING HYDROGEN RENEWABLE feedstock
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Assessment of Feedstock Options for Biofuels Production in Ghana 被引量:1
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作者 Francis Kemausuor Joseph Oppong Akowuah Emmanuel Ofori 《Journal of Sustainable Bioenergy Systems》 2013年第2期119-128,共10页
In the wake of climate change and increasing fossil fuel prices, biofuels are becoming attractive to agricultural dependent economies in sub-Saharan Africa and other regions of the world. This study evaluates the ener... In the wake of climate change and increasing fossil fuel prices, biofuels are becoming attractive to agricultural dependent economies in sub-Saharan Africa and other regions of the world. This study evaluates the energy production potential of biomass resources grown on the available arable agricultural land under two principal scenarios: using 2.5% and 5% of the available arable land for energy crop expansion. Using conservative biofuel yields from crops in the sub-region, a 2.5% of uncultivated arable land dedicated to four traditional crops grown in Ghana namely maize, cassava, sweet sorghum and oil palm could potentially replace 9.3% and 7.2% of transportation fuels by 2020 and 2030 respectively. Using 5% of the uncultivated arable land to cultivate the above four crops and jatropha could potentially produce biofuel to replace 17.3% of transport fuels by 2020 and 13.3% by 2030. In order to enrol such a scheme, government is encouraged to put in place appropriate structures to ensure that, the industry meet international sustainability standards. 展开更多
关键词 Biofuels feedstock Ghana
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Sorghum as Dry Land Feedstock for Fuel Ethanol Production
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作者 WANG Donghai WU Xiaorong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期83-96,共14页
Dry land crops such as sorghums (grain sorghum, promising feedstocks for fuel ethanol production. The major issue sweet sorghum and forage sorghum) have been identified as for using the sweet sorghum as feedstock is... Dry land crops such as sorghums (grain sorghum, promising feedstocks for fuel ethanol production. The major issue sweet sorghum and forage sorghum) have been identified as for using the sweet sorghum as feedstock is its stability at room temperature. At room temperature, the sweet sorghum juice could lose from 40% to 50% of its fermentable sugars from 7 to 14 days No significant sugar content and profile changes were observed in juice stored at refrigerator temperature in two weeks. Ethanol fermentation efficiencies of fresh and frozen juice were high (-93%). Concentrated juice (≥25% sugar) had significantly lower efficiencies and large amounts of fructose left in finished beer; however, winery yeast strains and novel fermentation techniques may solve these problems. The ethanol yield from sorghum grain increased as starch content increased. No linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include starches and protein digestibility, amylose-lipid complexes, tannin content, and mash viscosity. Life cycle analysis showed a positive net energy value (NEV) = 25 500 Btu/gal ethanol. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) were used to determine changes in the structure and chemical composition of sorghum biomasses. Dilute sulfuric acid pretreatment was effective in removing the hemicellulose from biomasses and exposing the cellulose for enzymatic hydrolysis. Forage sorghum lignin had a lower syringyl/guaiacyl ratio and its pretreated biomass was easier to hydrolyze. Up to 72% hexose yield and 94% pentose yield were obtained by using a modified steam explosion with 2% sulfuric acid at 140℃ for 30 min and enzymatic hydrolysis with cellulase. 展开更多
关键词 dilute acid pretreatment dry land feedstock FTIR fuel ethanol SORGHUM XRD
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Study on the Adaptability of Etherification Feedstock to Reactor Type
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作者 Mao Junyi Yuan Qing +1 位作者 Wang Lei Huang Tao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第2期57-62,共6页
A reactive C5 olefins and methanol etherification kinetic model based on E-R mechanism was established and three different types of reactors including the adiabatic fixed-bed liquid reactor, the external loop reactor ... A reactive C5 olefins and methanol etherification kinetic model based on E-R mechanism was established and three different types of reactors including the adiabatic fixed-bed liquid reactor, the external loop reactor and the mixedphase reactor were constructed by Aspen Plus. The adaptability of reactive C5 olefins to these reactors was studied and simulated using various gasoline fractions with different olefins content. After the theoretical model was validated by the experimental data of the etherification of three C5 light cut fractions from different gasoline sources in different reactors, the simulated isoamylene conversion with reactive C5 olefin contents increasing from 10% to 60% was studied in the three different types of reactors for etherification with methanol, respectively. Test results show that there is an obvious adaptability of the feedstock composition to the reactor type to achieve a high conversion. 展开更多
关键词 ETHERIFICATION REACTOR feedstock ADAPTABILITY
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Strategy of changing cracking furnace feedstock based on improved group search optimization
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作者 年笑宇 王振雷 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期181-191,共11页
The scheduling process of cracking furnace feedstock is important in an ethylene plant. In this paper it is described as a constraint optimization problem. The constraints consist of the cycle of operation, maximum tu... The scheduling process of cracking furnace feedstock is important in an ethylene plant. In this paper it is described as a constraint optimization problem. The constraints consist of the cycle of operation, maximum tube metal temperature, process time of each feedstock, and flow rate. A modified group search optimizer is proposed to deal with the optimization problem. Double fitness values are defined for every group. First, the factor of penalty function should be changed adaptively by the ratio of feasible and general solutions. Second, the "excellent" infeasible solution should be retained to guide the search. Some benchmark functions are used to evaluate the new algorithm. Finally, the proposed algorithm is used to optimize the scheduling process of cracking furnace feedstock. And the optimizing result is obtained. 展开更多
关键词 Cracking furnace Scheduling of feedstock Group search optimizer Adaptive penalty function Double fitness values
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Methyl Ester Type Produced by Catalytic Transesterification:From Various Oil Feedstock to Biodiesel Products
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作者 Aman Santoso Sumari Sumari Muhammad Roy Asrori 《Energy Engineering》 EI 2022年第6期2255-2276,共22页
Biodiesel research has been carried out via transesterification.However,biodiesel products(methyl esters)have not encountered new insights,because feedstocks have been explored and studied.Various optimum conditions o... Biodiesel research has been carried out via transesterification.However,biodiesel products(methyl esters)have not encountered new insights,because feedstocks have been explored and studied.Various optimum conditions on transesterification reaction could produce different methyl ester type with different compound.So,this review describes various oil feedstock that were to find new insights about methyl ester type.The review took the results of study that has been published with experience for 10 years.The results of the study reviewed on the transesterification method,characterization of methyl esters,and its components.The component reviewed and correlated to the literature,structure,and GC-MS analysis.The review can provide challenges for methyl ester research in future research. 展开更多
关键词 BIODIESEL methyl ester TRANSESTERIFICATION feedstock catalytic reaction
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Catalytic Feedstock Recycling of Polymers
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作者 Raju Francis Beena Sethi 《Advances in Materials Physics and Chemistry》 2012年第4期263-266,共4页
This piece of study involves degradation of plastic waste in presence of two different catalysts. It was found in gas chromatography (GC) analysis results that in presence of these catalysts more than 80% of polymer b... This piece of study involves degradation of plastic waste in presence of two different catalysts. It was found in gas chromatography (GC) analysis results that in presence of these catalysts more than 80% of polymer by weight was converted into either liquid or gaseous hydrocarbons. These can be utilized as fuel or can be transformed into other useful products. Thermo gravimetric analysis (TGA) and differential scanning calorimetric (DSC) analysis of polymers suggest that presence of these catalysts lowers degradation temperature and change mechanism of degradation. 展开更多
关键词 Polymer Degradation Catalyst Green Chemistryr feedstock RECYCLING GC TGA DSC
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Effects of surfactant on properties of MIM feedstock 被引量:1
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作者 李益民 刘相权 +1 位作者 罗丰华 岳建岭 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第1期1-8,共8页
Effects of the surfactant for improving the properties of MIM feedstock were investigated. Feedstocks were prepared by 17-4PH stainless steel(SS) powder and paraffin wax-based binder containing different contents of s... Effects of the surfactant for improving the properties of MIM feedstock were investigated. Feedstocks were prepared by 17-4PH stainless steel(SS) powder and paraffin wax-based binder containing different contents of stearic acid(SA) as the surfactant. The viscosity of the feedstock decreases significantly when the SA is added. Besides, the wetting angle of the binder against the 17-4PH SS powder decreases greatly and the critical solid loading increases with the adding of the SA. Fourier transformation infrared spectroscopy(FTIR) analysis was used to prove the interaction between the SA and the 17-4PH SS powder. Chemical bonding is found on the surface of 17-4PH SS powder after mixing and it helps a lot to enhance the interacting force between the binder and the powder. Then an adsorbing model was adopted to estimate the least content of the surfactant that formed a monolayer adsorption on the mono-sized spherical powder (with smooth surface). The least content of the surfactant is calculated to be 0.19%. Whereas, the experiments indicate that about 5% is the optimal value to improve the properties of the feedstock. The reason may come from two aspects: firstly, the powders used in current experiment are not all mono-sized spheres and the coarse surface of the powder has a great effect on the adsorptive capacity of the powder; secondly, multilayer adsorption is likely to occur on the powder surface, which will also increase the adsorptive capacity. 展开更多
关键词 喷射造型法 金属加工 表面活性剂 合金
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Rheological properties of metal injection molding feedstock
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作者 李松林 李益民 +1 位作者 曲选辉 黄伯云 《中国有色金属学会会刊:英文版》 CSCD 2002年第1期105-108,共4页
Viscosity of a polyethylene glycol polymethyl methacrylate (PEG PMMA) binder and PEG PMMA/Fe 2Ni feedstock in powder injection molding was measured and calculated. A logarithmic additivity between viscosity of the bin... Viscosity of a polyethylene glycol polymethyl methacrylate (PEG PMMA) binder and PEG PMMA/Fe 2Ni feedstock in powder injection molding was measured and calculated. A logarithmic additivity between viscosity of the binder and that of its constituents was found. Other factors, such as temperature, powder loads, content and type of surface active agents and those of polymers, in relation to rheological properties of feedstock were discussed as well. The results showed that with increasing viscosity of surface active agent, polymer melt index or temperature, the feedstock viscosity decreased while higher polymer content and powder loading would lead to additional feedstock viscosity. The relationship mentioned above is expressed and effectively explained why the change rate of feedstock viscosity will slow down with the increase of shear rate. 展开更多
关键词 粉末注射成型 流变学 给料特性 胶合剂
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Recent Advances in Microbial Production of Terpenoids from Biomass-derived Feedstocks
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作者 CAO Yujin XIAN Mo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2024年第1期20-28,共9页
Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and biofuels.Traditionally,terpenoids are obtained from natural sources,such as plants,but their production is limited... Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and biofuels.Traditionally,terpenoids are obtained from natural sources,such as plants,but their production is limited by the insufficiency of resources and low yields of extraction.Microbial production of terpenoids has emerged as a promising alternative due to that it is sustainable and easy to scale up.This review aims to summarize recent advances in microbial production of terpenoids from inexpensive biomass-derived feedstocks.Metabolic pathways and key enzymes involved in terpenoid biosynthesis are introduced.Microorganisms that can utilize low-cost lignocellulosic feedstocks for terpenoid production are highlighted.The challenges and prospects faced by microbial terpenoid production are proposed.We believe that continuous progress in the fields of biomass transformation and synthetic biology will ultimately achieve industrial production of microbial terpenoids. 展开更多
关键词 TERPENOID Microbial production Biomass-derived feedstock Metabolic pathway
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