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A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints
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作者 Tushar Sonar Mikhail Ivanov +2 位作者 Evgeny Trofimov Aleksandr Tingaev Ilsiya Suleymanova 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期78-133,共56页
The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistan... The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion resistance.These alloys are manufactured by the equal mixing or larger proportions of five or more alloying elements.HEAs exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of mixing.Solid state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA joints.The HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs joints.The similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial applications.Thus,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi alloys.The state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints. 展开更多
关键词 High entropy alloys solid state welding MICROSTRUCTURE Mechanical properties
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Solid state recycling of Mg-Gd-Y-Zn-Zr alloy chips by isothermal sintering and equal channel angular pressing
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作者 Yanbo Pei Hongjun Ma +1 位作者 Meng Yuan Bugang Teng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期2725-2740,共16页
The Mg-7Gd-4Y-2Zn-0.5Zr alloy chips were successfully recycled through isothermal sintering and equal channel angular pressing(ECAP).The mechanical properties and microstructure evolution of samples during the recycli... The Mg-7Gd-4Y-2Zn-0.5Zr alloy chips were successfully recycled through isothermal sintering and equal channel angular pressing(ECAP).The mechanical properties and microstructure evolution of samples during the recycling process were studied in detail.The eutectic phases in the as-cast alloy transform into long period-stacking ordered(LPSO)phases after homogenization,which can improve the plasticity of the material.After isothermal sintering,the density of the sample is lower than that of the homogenized sample,and oxide films are formed adjacent to the bonding interface of the metal chips.Hence,the plasticity of the sintered sample is poor.Dense samples are fabricated after ECAP.Although the grains are not refined compared to the sintered sample,the microstructure becomes more uniform due to recrystallization.Fiber interdendritic LPSO phase and kinked 14H-LPSO phase are formed in the alloy due to the shear deformation during the ECAP process,which improves the strength and plasticity of the sample significantly.Furthermore,the basal texture is weakened due to the Bc route of the ECAP process,which can increase the Schmid factor of the basal slip system and improve the elongation of the sample.After 2 ECAP passes,the fully densified recycled billet shows superior mechanical properties with an ultimate tensile strength of 307.1 MPa and elongation of 11.1%. 展开更多
关键词 Mg-Gd-Y-Zn-Zr alloy solid state recycling Microstructure evolution LPSO phase Equal channel angular pressing
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A review of Al-based material dopants for high-performance solid state lithium metal batteries
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作者 Ying Tian Weicui Liu +6 位作者 Tianwei Liu Xiaofan Feng Wenwen Duan Wen Yu Hongze Li Nanping Deng Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期244-261,共18页
As the world transitions to green energy, there is a growing focus among many researchers on the requirement for high-efficient and safe batteries. Solid-state lithium metal batteries(SSLMBs) have emerged as a promisi... As the world transitions to green energy, there is a growing focus among many researchers on the requirement for high-efficient and safe batteries. Solid-state lithium metal batteries(SSLMBs) have emerged as a promising alternative to traditional liquid lithium-ion batteries(LIBs), offering higher energy density, enhanced safety, and longer lifespan. The rise of SSLMBs has brought about a transformation in energy storage, with aluminum(Al)-based material dopants playing a crucial role in advancing the next generation of batteries. The review highlights the significance of Al-based material dopants in SSLMBs applications, particularly its contributions to solid-state electrolytes(SSEs), cathodes, anodes,and other components of SSLMBs. Some studies have also shown that Al-based material dopants effectively enhance SSE ion conductivity, stabilize electrode and SSE interfaces, and suppress lithium dendrite growth, thereby enhancing the electrochemical performance of SSLMBs. Despite the above mentioned progresses, there are still problems and challenges need to be addressed. The review offers a comprehensive insight into the important role of Al in SSLMBs and addresses some of the issues related to its applications, endowing valuable support for the practical implementation of SSLMBs. 展开更多
关键词 Al-based material dopants solid state lithium metal batteries solid-state electrolytes Action mechanisms and structure designs Optimization strategies
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新时代背景下焊接专业全英文课程建设与改革实践——以《Solid State Welding》为例
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作者 杨夏炜 苏宇 +2 位作者 马铁军 徐雅欣 李文亚 《焊接技术》 2024年第4期145-148,共4页
在全球国际化和国家战略“双一流”建设的背景下,积极构建焊接技术与工程专业或焊接方向的国际化人才培养体系与模式,大力推进全英文课程的建设与改革,加快培养焊接领域国际化综合人才具有十分重要的意义。课程建设与改革是新工科建设... 在全球国际化和国家战略“双一流”建设的背景下,积极构建焊接技术与工程专业或焊接方向的国际化人才培养体系与模式,大力推进全英文课程的建设与改革,加快培养焊接领域国际化综合人才具有十分重要的意义。课程建设与改革是新工科建设的实施途径,文中以《Solid State Welding》全英文课程实践为例,不断完善新工科焊接方向课程体系建设,构建与国际接轨的教学内容与方法,将国际化视野、国际化教学思维及方法融入到全英文教育教学中,使学生在掌握国际课程知识的基础上,开拓国际视野,有效培养国际交流与合作能力。 展开更多
关键词 焊接 solid state Welding 全英文课程 国际化视野 课程建设
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Synergistic interactions between the charge‐transport and mechanical properties of the ionic‐liquid‐based solid polymer electrolytes for solid‐state lithium batteries 被引量:2
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作者 Ashutosh Agrawal Saeed Yari +3 位作者 Hamid Hamed Tom Gouveia Rongying Lin Mohammadhosein Safari 《Carbon Energy》 SCIE EI CAS CSCD 2023年第11期44-53,共10页
The performance sensitivity of the solid‐state lithium cells to the synergistic interactions of the charge‐transport and mechanical properties of the electrolyte is well acknowledged in the literature,but the quanti... The performance sensitivity of the solid‐state lithium cells to the synergistic interactions of the charge‐transport and mechanical properties of the electrolyte is well acknowledged in the literature,but the quantitative insights therein are very limited.Here,the charge‐transport and mechanical properties of a polymerized ionic‐liquid‐based solid electrolyte are reported.The transference number and diffusion coefficient of lithium in the concentrated solid electrolyte are measured as a function of concentration and stack pressure.The elastoplastic behavior of the electrolyte is quantified under compression,within a home‐made setup,to substantiate the impact of stack pressure on the stability of the Li/electrolyte interface in the symmetric lithium cells.The results spotlight the interaction between the concentration and thickness of the solid electrolyte and the stack pressure in determining the polarization and stability of the solid‐state lithium batteries during extended cycling. 展开更多
关键词 BATTERY DIFFUSION pressure solid state TRANSFERENCE
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Incombustible solid polymer electrolytes:A critical review and perspective
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作者 Kai Wu Jin Tan +4 位作者 Zhenfang Liu Chenguang Bao Ao Li Qi Liu Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期264-281,I0007,共19页
Since the advent of the solid-state batteries,employing solid polymer electrolytes(SPEs)to replace routine flammable liquid electrolytes is regarded to be one of the most promising solutions in pursing highenergy-dens... Since the advent of the solid-state batteries,employing solid polymer electrolytes(SPEs)to replace routine flammable liquid electrolytes is regarded to be one of the most promising solutions in pursing highenergy-density battery systems.SPEs with superior thermal stability,good processability,and high mechanical modulus obtain increasing attentions.However,SPE-based batteries are not impenetrable due to their decomposition and combustibility under extreme conditions.Researchers believe incorporating appropriate flame-retardant additives/solvents/fragments into SPEs can intrinsically reduce their flammability to solve the battery safety issues.In this review,the recent research progress of incombustible SPEs,with special emphasis on flame-retardant structural design,is summarized.Specifically,a brief introduction of flame-retardant mechanism,evaluation index for safety of SPEs,and a detailed overview of the latest advances on diverse-types SPEs in various battery systems are highlighted.The deep insight into thermal ru naway process,the free-standing incombustible GPEs,and the ratio nal design of pouch cell structures may be the main directions to motivate revolutionary next-generation for safety batteries. 展开更多
关键词 Non-flammable electrolyte solid polymer electrolyte High safety electrolyte solid state electrolyte solid state battery
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Solid Rocket Booster Thrust Asynchrony Identification Method for Solid Rocket Bundled Rockets With ESO
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作者 WU Kao ZHANG Chi +2 位作者 CHEN Yan XU Guoguang BU Xiangwei 《Aerospace China》 2024年第1期40-46,共7页
The role of the rocket attitude control system is to execute the required maneuvers for guidance and ensure the stability of the rocket's flight attitude. Attitude control technology has always been one of the key... The role of the rocket attitude control system is to execute the required maneuvers for guidance and ensure the stability of the rocket's flight attitude. Attitude control technology has always been one of the key technologies for ensuring the success of rocket flights and has been a core topic in carrier rocket technology research. The Gravity-1 solid carrier rocket is the first solid rocket bundled rocket developed by China, adopting a configuration with four boosters and a core stage bundled together. During the actual flight process, the four booster engines are ignited first, and then, in the event of insufficient control force from the boosters, the core stage engine is ignited to participate in control. To address thrust asynchrony during the descent of the four boosters, an Extended State Observer(ESO) is employed in the control scheme for this flight segment. This involves real-time estimation and compensation of attitude parameters during flight, identification of thrust asynchrony among the boosters, and simultaneous determination of whether the core stage engine is ignited to participate in control.Through six degrees of freedom simulation analysis and Y1 flight test validation, this method has been proven to be correct and feasible. 展开更多
关键词 Extended state Observer(ESO) solid booster attitude control thrust asynchrony
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Applications of Floquet-Magnus and Fer Expansion Approaches during Cross Polarization Radiation in Solid State NMR
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作者 Eugene Stephane Mananga Thibault Charpentier 《Journal of Modern Physics》 2023年第7期1136-1156,共21页
This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR)... This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR): namely, the Floquet-Magnus expansion and the Fer expansion. We use the aforementioned expansion schemes for the calculation of effective Hamiltonians and propagators when the spin system undergoes Cross Polarization radiation. CP is the gateway experiment into SSNMR. An in-depth comprehension of the underlying mechanics of spin dynamics during the cross-polarization experiment is pivotal for further experimental developments and optimization of more complex solid-state NMR experiments. The main contribution of this work is a prospect related to spin physics;particularly regarding to generalization of the calculation. This work reports original yet interesting novel ideas and developments that include calculations performed on the CP experiment. In fact, the approach presented could play a major role in the interpretation of several fine NMR experiments in solids, which would in turn provide significant new insights in spin physics. The generality of the work points towards potential applications in problems related in solid-state NMR and theoretical developments of spectroscopy as well as interdisciplinary research areas as long as they include spin dynamics concepts. 展开更多
关键词 Cross Polarization solid-state NMR Floquet-Magnus Expansion Fer Expansion Spin Dynamics
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Microstructure and mechanical properties of Mg-Zn-Y-Zr alloy prepared by solid state recycling 被引量:2
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作者 赵祖德 陈强 +2 位作者 杨林 舒大禹 赵志翔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期265-271,共7页
Machined chips of Mg-Zn-Y-Zr alloy were consolidated by cold pressing and then hot extrusion under various processing temperatures and extrusion ratios. The results show that the microstructure of the chip-extruded al... Machined chips of Mg-Zn-Y-Zr alloy were consolidated by cold pressing and then hot extrusion under various processing temperatures and extrusion ratios. The results show that the microstructure of the chip-extruded alloy is marked by a large number of recrystallized grains and some unrecrystallized grains, which results in high strength but low ductility at temperatures below 320 ℃. With increasing processing temperature up to 360 ℃, entirely recrystallized and equiaxed grains are obtained. Mg-Zn-Y-Zr alloy with low strength but high ductility is obtained compared with the alloy processed at low temperature. At 420℃, coarse and equiaxed grains are formed, which results in the drastic decrease of mechanical properties. With increasing extrusion ratio from 8 to 16, the grain refinement is more obvious and the mechanical properties at room temperature are improved effectively. However, the yield strength and ultimate tensile strength are improved a little with further increasing extrusion ratio. 展开更多
关键词 Mg-Zn-Y-Zr alloy extrusion ratio solid state recycling processing temperature
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Microwave direct synthesis and thermoelectric properties of Mg_(2)Si by solid-state reaction 被引量:2
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作者 周书才 白晨光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1785-1789,共5页
In order to reduce the oxidation and volatilization caused by Mg element in the traditional methods for synthesizing Mg2Si compounds,Mg2Si thermoelectric materials were prepared by solid state reaction and microwave r... In order to reduce the oxidation and volatilization caused by Mg element in the traditional methods for synthesizing Mg2Si compounds,Mg2Si thermoelectric materials were prepared by solid state reaction and microwave radiation techniques.Structure and phase composition of the materials were investigated by X-ray diffraction.The electrical conductivity,Seebeck coefficient and thermal conductivity were measured as a function of temperature from 300 to 700 K.It is found that high purity Mg2Si powders can be obtained with excessive content of 8% Mg from the stoichiometric Mg2Si at 853 K and 2.5 kW for 30 min.A maximum dimensionless figure of merit,ZT,of about 0.13 was obtained for Mg2Si at 600 K. 展开更多
关键词 MG2SI thermoelectric materials solid state reaction microwave synthesis
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Supercritical-hydrothermal accelerated solid state reaction route for synthesis of LiMn_2O_4 cathode material for high-power Li-ion batteries 被引量:1
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作者 刘学武 汤洁 +2 位作者 覃旭松 邓远富 陈国华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1414-1424,共11页
Synthesis of the spinel structure lithium manganese oxide (LiMn2O4) by supercritical hydrothermal (SH) accelerated solid state reaction (SSR) route was studied. The impacts of the reaction pressure, reaction tem... Synthesis of the spinel structure lithium manganese oxide (LiMn2O4) by supercritical hydrothermal (SH) accelerated solid state reaction (SSR) route was studied. The impacts of the reaction pressure, reaction temperature and reaction time of SH route, and the calcination temperature of SSR route on the purity, particle morphology and electrochemical properties of the prepared LiMn2O4 materials were studied. The experimental results show that after 15 min reaction in SH route at 400 ℃ and 30 MPa, the reaction time of SSR could be significantly decreased, e.g. down to 3 h with the formation temperature of 800 ℃, compared with the conventional solid state reaction method. The prepared LiMn2O4 material exhibits good crystallinity, uniform size distribution and good electrochemical performance, and has an initial specific capacity of 120 mA.h/g at a rate of 0.1C (1C=148 mA/g) and a good rate capability at high rates, even up to 50C. 展开更多
关键词 lithium ion battery LIMN2O4 supercritical water solid state reaction high rate capability
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Solid state fermentation of rapeseed cake with Aspergillus niger for degrading glucosinolates and upgrading nutritional value 被引量:36
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作者 Changyou Shi Jun He +5 位作者 Jie Yu Bing Yu Zhiqing Huang Xiangbing Mao Ping Zheng Daiwen Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第3期340-346,共7页
Background: Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates (GIs), phytic acid, tannins etc. In th... Background: Rapeseed cake is a good source of protein for animal feed but its utilization is limited due to the presence of anti-nutritional substances, such as glucosinolates (GIs), phytic acid, tannins etc. In the present study, a solid state fermentation (SSF) using Aspergillus niger was carried out with the purpose of degrading glucosinolates and improving the nutritional quality of rapeseed cake (RSC). The effects of medium composition and incubation conditions on the GIs content in fermented rapeseed cake (FRSC) were investigated, and chemical composition and amino acid in vitro digestibility of RSC substrate fermented under optimal conditions were determined. Results: After 72 h of incubation at 34℃, a 76.89% decrease in GIs of RSC was obtained in solid medium containing 70% RSC, 30% wheat bran at optimal moisture content 60% (w/w). Compared to unfermented RSC, trichloroacetic acid soluble protein (TCA-SP), crude protein and ether extract contents of the FRSC were increased (P〈 0.05) 103.71, 23.02 and 23.54%, respectively. As expected, the contents of NDF and phytic acid declined (P〈 0.05) by 9.12 and 44.60%, respectively. Total amino acids (TAA) and essential amino acids (EAA) contents as well as AA in vitro digestibility of FRSC were improved significantly (P 〈 0.05). Moreover, the enzyme activity of endoglucanase, xylanase, acid protease and phytase were increased (P 〈 0.05) during SSF. Conclusions: Our results indicate that the solid state fermentation offers an effective approach to improving the quality of proteins sources such as rapeseed cake. 展开更多
关键词 Aspergillus niger GLUCOSINOLATES Nutritional value Rapeseed cake solid state fermentation
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Utilization of winery wastes for Trichoderma viride biocontrol agent production by solid state fermentation 被引量:12
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作者 BAI Zhihui JIN Bo +2 位作者 LI Yuejie CHEN Jian LI Zuming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第3期353-358,共6页
Biocontrol agents are safe and environmental friendly alternatives for pesticides in agriculture application. Trichoderma viride WEBL0703 performed a high level of antagonistic activity toward a broad spectrum of phyt... Biocontrol agents are safe and environmental friendly alternatives for pesticides in agriculture application. Trichoderma viride WEBL0703 performed a high level of antagonistic activity toward a broad spectrum of phytopathogens and was determined as a biocontrol agent, which was produced by solid state fermentation using grape marc and wine lees. The maximum yield of T. viride conidia was up to 6.65 × 10^9 CFU/g initial dry substrate (IDS) after 10 d fermentation. As important enzymes for protecting plants from disease, chitinase, β-glucanase, and pectinase yields were 47.8 U/g IDS, 8.32 U/g IDS and 9.83 U/g IDS, respectively. These results show that it is feasible to convert winery wastes to a value-added and environmental friendly biocontrol agent. 展开更多
关键词 grape marc wine lees biocontrol agent Trichoderrna viride solid state fermentation
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Solid state interfacial reactions in electrodeposited Ni/Sn couples 被引量:4
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作者 Wen-ming Tang An-qiang He +1 位作者 Qi Liu Douglas-G. Ivey 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第4期459-463,共5页
Ni/Sn couples, prepared by sequentially electroplating Ni layers and Sn layers on metallized Si wafers, were employed to study the microstructures and growth kinetics of Ni-Sn intermediate phases, when the Ni/Sn coupl... Ni/Sn couples, prepared by sequentially electroplating Ni layers and Sn layers on metallized Si wafers, were employed to study the microstructures and growth kinetics of Ni-Sn intermediate phases, when the Ni/Sn couples were aged at room temperature or armealed at temperatures from 150 to 225℃ for various times. The results show that the NiSn phase and Ni3Sn4 phase are formed, respectively, in the aged couples and annealed couples. The Ni3Sn4 layer is continuously distributed between the Ni and Sn sides in the annealed Ni/Sn couples. The Ni3Sn4 growth follows parabolic growth kinetics with an apparent activation energy of 39.0 kJ/mol. 展开更多
关键词 ELECTRODEPOSITION solid state reaction DIFFUSION MICROSTRUCTURE KINETICS
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A Dye-sensitized Nanocrystalline Solid State Photovoltaic Cell 被引量:5
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作者 Dong She ZHANG Xu Rui XIAO Laboratory of photochemistry, Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期813-814,共2页
A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine deri... A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3Py+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer. 展开更多
关键词 nanocrystalline TiO2 electrode dye sensitization solid state cell
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SUPERPLASTICITY AND SOLID STATE BONDING OF TITANIUM ALLOYS 被引量:4
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作者 R. Ya. Lutfullin, O.A. Kaibyshev, R.V. Safiullin, O.R. Valiakhmetov and M.H. Mukhametrahimov Institute for Metals Superplasticity Problems, Russian Academy of Sciences, Ufa 450001, Russia 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期561-566,共6页
Experimental results related to solid state weldability of superplastic titanium alloys are presented. A correlation between superplastic flow and enhanced solid state weldability was established. It has been experim... Experimental results related to solid state weldability of superplastic titanium alloys are presented. A correlation between superplastic flow and enhanced solid state weldability was established. It has been experimentally shown that a drop in the lower superplastic flow temperature with decreasing mean grain size provides an opportunity to decrease the temperature at whicmethods for titanium alloys. 展开更多
关键词 SUPERPLASTICITY titanium alloy solid state bonding
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Paddy Husk as Support for Solid State Fermentation to Produce Xylanase from Bacillus pumilus 被引量:4
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作者 Ranganathan KAPILAN Vasanthy ARASARATNAM 《Rice science》 SCIE 2011年第1期36-45,共10页
To optimize culture conditions for xylanase production by solid state fermentation (SSF) using Bacillus pumilus, with paddy husk as support, solid medium contained 200 g of paddy husk with 800 mL of liquid fermentat... To optimize culture conditions for xylanase production by solid state fermentation (SSF) using Bacillus pumilus, with paddy husk as support, solid medium contained 200 g of paddy husk with 800 mL of liquid fermentation medium [xylan, 20.0 g/L; peptone, 2.0 g/L; yeast extract, 2.5 g/L; K2HPO4, 2.5 g/L; KH2PO4, 1.0 g/L; NaCl, 0.1 g/L; (NH4)2SO4, 2.0 g/L, CaCl2-2H2O, 0.005 g/L; MgCl2.6H2O, 0.005 g/L; and FeCI3, 0.005 g/L] at pH 9.0 was applied. The highest xylanase activity (142.0 ±0.47 U/g DM] was obtained on the 6th day at 30℃ The optimized paddy husk to liquid fermentation medium ratio was 2:9, and the optimized culture temperature was 40℃. When commercial Birchwood xylan was replaced with different concentrations of corncob, xylanase production was maximized (224.2 U/g DM) in the medium with 150 g/L corncob. Xylanase production was increased by sucrose, fructose and arabinose, whereas reduced by glucose, galactose, lactose and amylose. When organic nitrogen sources were replaced with locally available nitrogen sources such as groundnut powder or sesame seedcake powder or coconut seedcake powder or soy meal powder, the highest xylanase production (290.7 U/g DM) was obtained in the medium with soy meal powder and 16.0 g/L of soy meal powder was the optimum (326.5±0.34 U/g DM). Based on the optimization studies, B. pumilus produced 2.3 times higher xylanase activity. The medium cost was reduced from 2 458.3 to 178.3 SLR/kg and the total activity which could be obtained from 1 kg of the medium was increased from 48 624 to 220 253 Units. 展开更多
关键词 Bacillus pumilus solid state fermentation XYLANASE paddy husk XYLAN CORNCOB soymeal
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An Efficient Solid State Method for Deoximation under Mild Conditions 被引量:3
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作者 Wang ZHOU Qian He LI Sha PENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第12期1559-1562,共4页
Oximes of ketones and aldehydes are efficiently converted to the corresponding carbonyl compounds, using a combination of NaHSO4.H20 and paraformaldehyde in good to excellent yields under solid state conditions at roo... Oximes of ketones and aldehydes are efficiently converted to the corresponding carbonyl compounds, using a combination of NaHSO4.H20 and paraformaldehyde in good to excellent yields under solid state conditions at room temperature for 10 minutes. 展开更多
关键词 solid state DEOXIMATION OXIME carbonyl compound.
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Cellulase production by Aspergillus unguis in solid state fermentation 被引量:2
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作者 K.Shruthi P.Suresh Yadav +1 位作者 B.V.Siva Prasad M.Subhosh Chandra 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期205-212,共8页
Lignocellulosic substrates are a good carbon source and provide rich growth media for a variety of microorganisms which prodLuce industrially important enzymes. Cellulases are a group of hydrolytic enzymes such as fil... Lignocellulosic substrates are a good carbon source and provide rich growth media for a variety of microorganisms which prodLuce industrially important enzymes. Cellulases are a group of hydrolytic enzymes such as filter paperase (FPase), carboxymethyl cellulase(CMCase) andβ-glucosidase-responsible for release of sugars in the bioconversion of the lignocellulosic biomass into a variety of value-added products. This study examined cellulase production by a newly isolated Aspergillus unguis on individual lignocellulosic substrates in solid state fermentation (SSF). The maximum peak production of enzymes varied from one substrate to another, however,based on the next best solid support and local availability of groundnut fodder supported maximum enzyme yields compared with other solid supports used in this study.Groundnut fodder supported significant production of FPase (5.9 FPU/g of substrate), CMCase (1.1 U/g of substrate) andβ-glucosidase activity (6.5 U/g of substrate) in SSF. Considerable secretion of protein (27.0 mg/g of substrate) on groundnut fodder was recorded. Constant increment of protein content in groundnut fodder due to cultivation of A. unguis is an interesting observation and it has implications for the improvement of nutritive value of groundnut fodder for cattle. 展开更多
关键词 LIGNOCELLULOSIC SUBSTRATES ASPERGILLUS unguis CELLULASE solid state FERMENTATION
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Wavelet analysis of ultrasonic A-scan signal of solid-state welded joints 被引量:4
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作者 史耀武 陈建忠 《China Welding》 EI CAS 2000年第1期22-29,共8页
In the ultrasonic nondestructive evaluation of the quality of solid state welded joints, such as friction bonding and diffusion bonding, the main difficulty is the identification of micro defects which are most likel... In the ultrasonic nondestructive evaluation of the quality of solid state welded joints, such as friction bonding and diffusion bonding, the main difficulty is the identification of micro defects which are most likely to emerge in the welding process. The ultrasonic echo on the screen of a commercial ultrasonic detector due to a micro defect is so weak that it is completely masked by noise, and impossible to be pointed out. In the present paper, wavelet analysis (WA) is utilized to process A scan ultrasonic signals from weak bonding defects in friction bonding joints and porosity in diffusion bonding joints. First, perception of WA for engineers is given, which demonstrates the physical mechanism of WA when applied to signal processing. From this point of view, WA can be understood easily and more thoroughly. Then the signals from welding joints are decomposed into a time scale plane by means of WA. We notice that noise and the signal echo attributed to the micro defect occupy different scales, which make it possible to enhance the signal to noise ratio of the signals by proper selection and threshold processing of the time scale components of the signals, followed by reconstruction of the processed components. 展开更多
关键词 wavelet analysis solid state bonding nondestructive evaluation ultrasonic testing
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