In the process of production or processing of materials by various methods,there is a need for a large volume of water of the required quality.Today in many regions of the world,there is an acute problem of providing ...In the process of production or processing of materials by various methods,there is a need for a large volume of water of the required quality.Today in many regions of the world,there is an acute problem of providing industry with water of a required quality.Its solution is an urgent and difficult task.The water quality of surface water bodies is formed by a combination of a large number of both natural and anthropogenic factors,and is often significantly heterogeneous not only in the water area,but also in depth.As a rule,the water supply of large industrial enterprises is located along the river network.Mergers are the most important nodes of river systems.Understanding the mechanism of transport of pollutants at the confluence of rivers is critical for assessing water quality.In recent years,thanks to the data of satellite images,the interest of researchers in the phenomenon of mixing the waters of merging rivers has increased.The nature of the merger is influenced by the formation of transverse circulation.Within the framework of this work,a study of vorticity,as well as the width of the mixing zone,depending on the distance from the confluence,the speeds of the merging rivers and the angle of confluence was carried out.Since the consumer properties of water are largely determined by its chemical and physical indicators,the intensity of mixing,determined largely by the nature of the secondary circulation,is of fundamental importance for assessing the distribution of hydrochemical indicators of water quality in the mixing zone.These characteristics are important not only for organizing water intake for drinking and technical purposes with the best consumer properties,but also for organizing an effective monitoring system for confluence zones.展开更多
The radial ultrasonic rolling electrochemical micromachining(RUR-EMM)combined rolling electrochemical micromachining(R-EMM)and ultrasonic vibration was studied in this paper.The fundamental understanding of the machin...The radial ultrasonic rolling electrochemical micromachining(RUR-EMM)combined rolling electrochemical micromachining(R-EMM)and ultrasonic vibration was studied in this paper.The fundamental understanding of the machining process especially the interaction between multiphysics in the interelectrode gap(IEG)was investigated and discussed by the finite element method.The multiphysics coupling model including flow field model,Joule heating model,material dissolution model and vibration model was built.3D multiphysics simulation based on micro dimples process in RUR-EMM and R-EMM was proposed.Simulation results showed that the electrolyte flowed into and out IEG periodically,gas bubbles were easy to squeeze out and the gas void fraction deceased about 16%to 54%,the maximum current density increased by 1.36 times in RUR-EMM than in R-EMM in one vibration period of time.And application of the ultrasonic vibration increased the electrolyte temperature about 1.3–4.4%in IEG.Verification experiments of the micro dimple process denoted better corrosion consistency of array dimples in RUR-EMM,there was no island at the micro dimple bottom which always formed in R-EMM,and an aggregated deviation of less than 8.7%for the micro dimple depth and 4%for the material removal amount between theory and experiment was obtained.展开更多
Continuous material processing operations like printing and textiles manufacturing are conducted under highly variable conditions due to changes in the environment and/or in the materials being processed.As such,the p...Continuous material processing operations like printing and textiles manufacturing are conducted under highly variable conditions due to changes in the environment and/or in the materials being processed.As such,the processing parameters require robust real-time adjustment appropriate to the conditions of a nonlinear system.This paper addresses this issue by presenting a hybrid feedforward-feedback nonlinear model predictive controller for continuous material processing operations.The adaptive feedback control strategy of the controller augments the standard feedforward control to ensure improved robustness and compensation for environmental disturbances and/or parameter uncertainties.Thus,the controller can reduce the need for manual adjustments.The controller applies nonlinear generalized predictive control to generate an adaptive control signal for attaining robust performance.A wavelet-based neural network model is adopted as the prediction model with high prediction precision and time-frequency localization characteristics.Online training is utilized to predict uncertain system dynamics by tuning the wavelet neural network parameters and the controller parameters adaptively.The performance of the controller algorithm is verified by both simulation,and in a real-time practical application involving a single-input single-output double-zone sliver drafting system used in textiles manufacturing.Both the simulation and practical results demonstrate an excellent control performance in terms of the mean thickness and coefficient of variation of output slivers,which verifies the effectiveness of this approach in improving the long-term uniformity of slivers.展开更多
A wireless search system was integrated on Windows 2000 server.Based on the communication principle between wireless data and Internet,the object expression of search file,the automatic query of document information,t...A wireless search system was integrated on Windows 2000 server.Based on the communication principle between wireless data and Internet,the object expression of search file,the automatic query of document information,the segment browsing of result information,and the receiving and sending of user information were realized by using Active Server Page 3.0,VB Script,WML Script insert languages and object orient database technology.The requirement querying information of material processing through Internet by GPRS,WAP mobile handset and so on was accomplished.展开更多
Nowadays, with the rapid development of science and technology, taking into account the rapid progress of science and the improvement of metal production precision in industry, laser technology provides technical supp...Nowadays, with the rapid development of science and technology, taking into account the rapid progress of science and the improvement of metal production precision in industry, laser technology provides technical support for high precision metal processing. Laser machining as a material processing technology is widely used in industrial production. This paper studies the application status and prospect of laser technology in the field of material processing.展开更多
Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable proc...Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable processing precision,diverse processing capabilities,and broad material adaptability.The processing abilities and applications of the ultrafast laser still need more exploration.In the field of material processing,controlling the atomic scale structure in nanomaterials is challenging.Complex effects exist in ultrafast laser surface/interface processing,making it difficult to modulate the nanostructure and properties of the surface/interface as required.In the ultrafast laser fabrication of micro functional devices,the processing ability needs to be improved.Here,we review the research progress of ultrafast laser micro/nano fabrication in the areas of material processing,surface/interface controlling,and micro functional devices fabrication.Several useful ultrafast laser processing methods and applications in these areas are introduced.With various processing effects and abilities,the ultrafast laser processing technology has demonstrated application values in multiple fields from science to industry.展开更多
We demonstrate an all polarization-maintaining(PM) fiber mode-locked laser seeded, hybrid fiber/solid-slab picosecond pulse laser system which outputs 40 μJ, 10 ps pulses at the central wavelength of 1064 nm. The bea...We demonstrate an all polarization-maintaining(PM) fiber mode-locked laser seeded, hybrid fiber/solid-slab picosecond pulse laser system which outputs 40 μJ, 10 ps pulses at the central wavelength of 1064 nm. The beam quality factors M2 in the unstable and stable directions are 1.35 and 1.31, respectively. 15 μJ picosecond pulses at the central wavelength of 355 nm are generated through third harmonic generation(THG) by using two Li B3 O5(LBO) crystals, in order to get better processing efficiency on polycrystalline diamonds. The high pulse energy and beam quality of these ultraviolet(UV) picosecond pulses are confirmed by latter experiments of material processing on polycrystalline diamonds. This scheme which combines the advantages of the all PM fiber mode-locked laser and the solid-slab amplifier enables compact, robust and chirped pulse amplification-free amplification with high power picosecond pulses.展开更多
The DGW-I is a new material processing facility developed in China,which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again,and successfull...The DGW-I is a new material processing facility developed in China,which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again,and successfully processed 6 samples of materials,including 3 samples of alloys,2 of semiconductors and 1 sample of oxide crystal.展开更多
Microwave processing has been taken into consideration for various purposes,not only for cooking,drying and enhancement of solution reaction kinetics but also various high temperature processes.In the presentation,sel...Microwave processing has been taken into consideration for various purposes,not only for cooking,drying and enhancement of solution reaction kinetics but also various high temperature processes.In the presentation,selected research projects conducted in our group will be reported.The first topic is the microwave processing for recycling valuable metals from by-products originated in the iron and steel industries.We studied microwave application to handling of the pickling sludge,which occurs in stainless steel rolling process.Microwave use for dehydration and carbo-thermic reduction processes was attempted.Next,because Pb elution from the wasted funnel glass used for the cathod-ray tube is one of the serious environmental problems,microwave application to leaching process of Pb from a Pb-conatining glass was performed.The kinetic study of the acid dissolution was performed.Last topic is fabrication of filter material for burning particulate matter(PM)from diesel engine(Diesel Particulate Filter:DPF).Microwave rapid heating characteristics are applied to the cold start(ignition)condition of engine for prevention of PM emission.展开更多
In recent years,femtosecond(fs)-lasers have evolved into a versatile tool for high precision micromachining of transparent materials because nonlinear absorption in the focus can result in refractive index modificatio...In recent years,femtosecond(fs)-lasers have evolved into a versatile tool for high precision micromachining of transparent materials because nonlinear absorption in the focus can result in refractive index modifications or material disruptions.However,when high pulse energies or low numerical apertures are required,nonlinear side effects such as self-focusing,filamentation or white light generation can decrease the modification quality.In this paper,we apply simultaneous spatial and temporal focusing(SSTF)to overcome these limitations.The main advantage of SSTF is that the ultrashort pulse is only formed at the focal plane,thereby confining the intensity distribution strongly to the focal volume and suppressing detrimental nonlinear side effects.Thus,we investigate the optical breakdown within a water cell by pump-probe shadowgraphy,comparing conventional focusing and SSTF under equivalent focusing conditions.The plasma formation is well confined for low pulse energies,2 mJ,but higher pulse energies lead to the filamentation and break-up of the disruptions for conventional focusing,thereby decreasing the modification quality.In contrast,plasma induced by SSTF stays well confined to the focal plane,even for high pulse energies up to 8 mJ,preventing extended filaments,side branches or break-up of the disruptions.Furthermore,while conventional focusing leads to broadband supercontinuum generation,only marginal spectral broadening is observed using SSTF.These experimental findings are in excellent agreement with numerical simulations of the nonlinear pulse propagation and interaction processes.Therefore,SSTF appears to be a powerful tool to control the processing of transparent materials,e.g.,for precise ophthalmic fs-surgery.展开更多
The construction industry is facing a big challenge in reducing the burden it is putting on the environment. There is an urgent need to develop and use eco-efficient construction materials with proper functional perfo...The construction industry is facing a big challenge in reducing the burden it is putting on the environment. There is an urgent need to develop and use eco-efficient construction materials with proper functional performance, a low carbon footprint and a less adverse impact on the environment. Nanotechnology is a new and very promising technology that helps fulfil the need for more environmentally friendly construction materials.展开更多
The research achievements of solidification theories and technologies in the last decades are reviewed with the stresses on some new development in the recent years. Some new interesting areas emerged in the last year...The research achievements of solidification theories and technologies in the last decades are reviewed with the stresses on some new development in the recent years. Some new interesting areas emerged in the last years are also pointed out.展开更多
Because there is neither waste rock nor mill tailings in the gypsum mine, and the buildings on the goaf of gypsum mine are needed to be protected, the research proposed the scheme of the clay filling technology. Gypsu...Because there is neither waste rock nor mill tailings in the gypsum mine, and the buildings on the goaf of gypsum mine are needed to be protected, the research proposed the scheme of the clay filling technology. Gypsum, cement, lime and water glass were used as adhesive, and the strength of different material ratios were investigated in this study. The influence factors of clay strength were obtained in the order of cement, gypsum, water glass and lime. The results show that the cement content is the determinant influence factor, and gypsum has positive effects, while the water glass can enhance both clay strength and the fluidity of the filing slurry. Furthermore, combining chaotic optimization method with neural network, the optimal ratio of composite cementing agent was obtained. The results show that the optimal ratio of water glass, cement, lime and clay (in quality) is 1.17:6.74:4.17:87.92 in the process of bottom self-flow filling, while the optimal ratio is 1.78:9.58:4.71:83.93 for roof-contacted filling. A novel filling process to fill in gypsum mine goaf with clay is established. The engineering practice shows that the filling cost is low, thus, notable economic benefit is achieved.展开更多
The First Pacific Rim International Confer-ence on Advanced Materials and Processing(PRICM-1)organized by The Chinese Society ofMetals(CSM),and co-sponsored by the Japan In-stitute of Metals(JIM),the Korean Institute ...The First Pacific Rim International Confer-ence on Advanced Materials and Processing(PRICM-1)organized by The Chinese Society ofMetals(CSM),and co-sponsored by the Japan In-stitute of Metals(JIM),the Korean Institute ofMetals(KIM)and The Mineral,Metals & Materi-als Society of the United States(TMS),was held inShangri-La Hotel,Hangzhou,China on June24-27,1992.It was the first large international conference展开更多
Ti1Al2O3 Functionally Gradient Material (FGM) was prepared by an explosive compaction/SHS process. Ten sheets of the compounding powder were laminated and pressed to get a green body of FGM. It was then compacted expl...Ti1Al2O3 Functionally Gradient Material (FGM) was prepared by an explosive compaction/SHS process. Ten sheets of the compounding powder were laminated and pressed to get a green body of FGM. It was then compacted explosively By burying the explosive compaction body into a stoichiometric Al/TiO2 mixture and igniting the combustion of the stoichiometric Al/TiO2 mixture, the SHS reaction of the explosive compaction body was initiated by the heat released from the combustion of the stoichiometric Al/TiO2 mixture. In this way, Ti/Al2O3 FGM was synthesized. The adiabatic temperatures of each gradient layer were calculated when the preheating temperatures were 298 K and 1173 K, respectively The microstructure, composition and properties of Ti/Al2O3 FGM and the reaction mechanism of each gradient layer were studied. It was found that Ti/Al2O3 FGM prepared by the explosive compaction/SHS process had a high density and a high microhardness. Its structure, composition and properties showed apparent gradient distribution. The structure of the standard stoichiometric ratio gradient layer of FGM was a network structure. Its reaction mode could be described as follows: Al powder melted first, then the molten Al penetrated into the TiO2 zone and reacted with TiO2, and big pores were left in the original positions of Al powder. The reaction of gradient layers with the addition of Al3O3 as diluents was similar to that of the standard stoichiometric ratio gradient layer, so were their structure and composition. However, the reaction of gradient layers with the addition of Ti as diluents was more complex and the composition deviated slightly from the designed one展开更多
A new concept named computational comminution is proposed in thispaper, which is different from the traditional studies on materialsprocessing procedure such as the study based on theoretic models, thestudy based on e...A new concept named computational comminution is proposed in thispaper, which is different from the traditional studies on materialsprocessing procedure such as the study based on theoretic models, thestudy based on experiment models, which is based on informationmodels. Some key technologies applied to mate- rials processingprocedure such as artificial neural networks, fuzzy sets, geneticalgorithms and visualization techn- ology are also presented, and afusing methodology of these new technologies is studied. Applicationin the cement grinding process of Horomill shows that results in thispaper are efficient.展开更多
The Joint Conference Organizing Committee of The Chinese Society of Metals(CSM),The Japan Insti-tute of Metals(JIM),The Korean Institute of Metals(KIM)and The Minerals,Metals & Materials Society(TMS)announces The ...The Joint Conference Organizing Committee of The Chinese Society of Metals(CSM),The Japan Insti-tute of Metals(JIM),The Korean Institute of Metals(KIM)and The Minerals,Metals & Materials Society(TMS)announces The First Pacific Rim International Conference on Advanced Materials and Processing(PRICM-1)which will be held in Hangzhou,China,in the last week of June,1992 lasting about four days.It is agreed that the PRICM-1 will be organized by The Chinese Society of Metals.展开更多
A dvanced Metallic Materials Research and Processing Technology Center was found in December 1998. As a unit under The College of Mechanical Engineering, the Center is an expansion of the former Cast and Composite Mat...A dvanced Metallic Materials Research and Processing Technology Center was found in December 1998. As a unit under The College of Mechanical Engineering, the Center is an expansion of the former Cast and Composite Materials Research Group, which was found in the early eighties of last century. The Center is focusing in the basic and applied research, and development of advanced metallic materials and their processing technology. It also functions as an organization展开更多
Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developme...Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.展开更多
Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developme...Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.展开更多
基金financial support from the Government of the Perm Territory within the Framework of Scientific Project No.S-26/828the Ministry of Science and High Education of Russia(Theme No.121031700169-1).
文摘In the process of production or processing of materials by various methods,there is a need for a large volume of water of the required quality.Today in many regions of the world,there is an acute problem of providing industry with water of a required quality.Its solution is an urgent and difficult task.The water quality of surface water bodies is formed by a combination of a large number of both natural and anthropogenic factors,and is often significantly heterogeneous not only in the water area,but also in depth.As a rule,the water supply of large industrial enterprises is located along the river network.Mergers are the most important nodes of river systems.Understanding the mechanism of transport of pollutants at the confluence of rivers is critical for assessing water quality.In recent years,thanks to the data of satellite images,the interest of researchers in the phenomenon of mixing the waters of merging rivers has increased.The nature of the merger is influenced by the formation of transverse circulation.Within the framework of this work,a study of vorticity,as well as the width of the mixing zone,depending on the distance from the confluence,the speeds of the merging rivers and the angle of confluence was carried out.Since the consumer properties of water are largely determined by its chemical and physical indicators,the intensity of mixing,determined largely by the nature of the secondary circulation,is of fundamental importance for assessing the distribution of hydrochemical indicators of water quality in the mixing zone.These characteristics are important not only for organizing water intake for drinking and technical purposes with the best consumer properties,but also for organizing an effective monitoring system for confluence zones.
基金financial support of the projects from the National Natural Science Foundation of China(Nos.51975532 and 51475428)the Zhejiang Provincial Natural Science Foundation(No.LY19E050007)。
文摘The radial ultrasonic rolling electrochemical micromachining(RUR-EMM)combined rolling electrochemical micromachining(R-EMM)and ultrasonic vibration was studied in this paper.The fundamental understanding of the machining process especially the interaction between multiphysics in the interelectrode gap(IEG)was investigated and discussed by the finite element method.The multiphysics coupling model including flow field model,Joule heating model,material dissolution model and vibration model was built.3D multiphysics simulation based on micro dimples process in RUR-EMM and R-EMM was proposed.Simulation results showed that the electrolyte flowed into and out IEG periodically,gas bubbles were easy to squeeze out and the gas void fraction deceased about 16%to 54%,the maximum current density increased by 1.36 times in RUR-EMM than in R-EMM in one vibration period of time.And application of the ultrasonic vibration increased the electrolyte temperature about 1.3–4.4%in IEG.Verification experiments of the micro dimple process denoted better corrosion consistency of array dimples in RUR-EMM,there was no island at the micro dimple bottom which always formed in R-EMM,and an aggregated deviation of less than 8.7%for the micro dimple depth and 4%for the material removal amount between theory and experiment was obtained.
文摘Continuous material processing operations like printing and textiles manufacturing are conducted under highly variable conditions due to changes in the environment and/or in the materials being processed.As such,the processing parameters require robust real-time adjustment appropriate to the conditions of a nonlinear system.This paper addresses this issue by presenting a hybrid feedforward-feedback nonlinear model predictive controller for continuous material processing operations.The adaptive feedback control strategy of the controller augments the standard feedforward control to ensure improved robustness and compensation for environmental disturbances and/or parameter uncertainties.Thus,the controller can reduce the need for manual adjustments.The controller applies nonlinear generalized predictive control to generate an adaptive control signal for attaining robust performance.A wavelet-based neural network model is adopted as the prediction model with high prediction precision and time-frequency localization characteristics.Online training is utilized to predict uncertain system dynamics by tuning the wavelet neural network parameters and the controller parameters adaptively.The performance of the controller algorithm is verified by both simulation,and in a real-time practical application involving a single-input single-output double-zone sliver drafting system used in textiles manufacturing.Both the simulation and practical results demonstrate an excellent control performance in terms of the mean thickness and coefficient of variation of output slivers,which verifies the effectiveness of this approach in improving the long-term uniformity of slivers.
基金Item Sponsored by Doctoral Program of Higher Education of China(97014515)
文摘A wireless search system was integrated on Windows 2000 server.Based on the communication principle between wireless data and Internet,the object expression of search file,the automatic query of document information,the segment browsing of result information,and the receiving and sending of user information were realized by using Active Server Page 3.0,VB Script,WML Script insert languages and object orient database technology.The requirement querying information of material processing through Internet by GPRS,WAP mobile handset and so on was accomplished.
文摘Nowadays, with the rapid development of science and technology, taking into account the rapid progress of science and the improvement of metal production precision in industry, laser technology provides technical support for high precision metal processing. Laser machining as a material processing technology is widely used in industrial production. This paper studies the application status and prospect of laser technology in the field of material processing.
基金supported by the National Natural Science Foundation of China(No.52075289)the Tsinghua-Jiangyin Innovation Special Fund(TJISF,No.2023JYTH0104).
文摘Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable processing precision,diverse processing capabilities,and broad material adaptability.The processing abilities and applications of the ultrafast laser still need more exploration.In the field of material processing,controlling the atomic scale structure in nanomaterials is challenging.Complex effects exist in ultrafast laser surface/interface processing,making it difficult to modulate the nanostructure and properties of the surface/interface as required.In the ultrafast laser fabrication of micro functional devices,the processing ability needs to be improved.Here,we review the research progress of ultrafast laser micro/nano fabrication in the areas of material processing,surface/interface controlling,and micro functional devices fabrication.Several useful ultrafast laser processing methods and applications in these areas are introduced.With various processing effects and abilities,the ultrafast laser processing technology has demonstrated application values in multiple fields from science to industry.
基金supported by the National Natural Science Foundation of China(Nos.61535009,11527808,61605142,and 61735007)the Tianjin Research Program of Application Foundation and Advanced Technology(No.17JCJQJC43500)
文摘We demonstrate an all polarization-maintaining(PM) fiber mode-locked laser seeded, hybrid fiber/solid-slab picosecond pulse laser system which outputs 40 μJ, 10 ps pulses at the central wavelength of 1064 nm. The beam quality factors M2 in the unstable and stable directions are 1.35 and 1.31, respectively. 15 μJ picosecond pulses at the central wavelength of 355 nm are generated through third harmonic generation(THG) by using two Li B3 O5(LBO) crystals, in order to get better processing efficiency on polycrystalline diamonds. The high pulse energy and beam quality of these ultraviolet(UV) picosecond pulses are confirmed by latter experiments of material processing on polycrystalline diamonds. This scheme which combines the advantages of the all PM fiber mode-locked laser and the solid-slab amplifier enables compact, robust and chirped pulse amplification-free amplification with high power picosecond pulses.
文摘The DGW-I is a new material processing facility developed in China,which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again,and successfully processed 6 samples of materials,including 3 samples of alloys,2 of semiconductors and 1 sample of oxide crystal.
文摘Microwave processing has been taken into consideration for various purposes,not only for cooking,drying and enhancement of solution reaction kinetics but also various high temperature processes.In the presentation,selected research projects conducted in our group will be reported.The first topic is the microwave processing for recycling valuable metals from by-products originated in the iron and steel industries.We studied microwave application to handling of the pickling sludge,which occurs in stainless steel rolling process.Microwave use for dehydration and carbo-thermic reduction processes was attempted.Next,because Pb elution from the wasted funnel glass used for the cathod-ray tube is one of the serious environmental problems,microwave application to leaching process of Pb from a Pb-conatining glass was performed.The kinetic study of the acid dissolution was performed.Last topic is fabrication of filter material for burning particulate matter(PM)from diesel engine(Diesel Particulate Filter:DPF).Microwave rapid heating characteristics are applied to the cold start(ignition)condition of engine for prevention of PM emission.
基金This study was supported by the Thuringian Ministry of Education,Science and Culture(OptiMi 2020-Graduate Research School‘Green Photonics’,B514-10061)the German Research Foundation(Leibniz program)the Carl Zeiss Foundation.
文摘In recent years,femtosecond(fs)-lasers have evolved into a versatile tool for high precision micromachining of transparent materials because nonlinear absorption in the focus can result in refractive index modifications or material disruptions.However,when high pulse energies or low numerical apertures are required,nonlinear side effects such as self-focusing,filamentation or white light generation can decrease the modification quality.In this paper,we apply simultaneous spatial and temporal focusing(SSTF)to overcome these limitations.The main advantage of SSTF is that the ultrashort pulse is only formed at the focal plane,thereby confining the intensity distribution strongly to the focal volume and suppressing detrimental nonlinear side effects.Thus,we investigate the optical breakdown within a water cell by pump-probe shadowgraphy,comparing conventional focusing and SSTF under equivalent focusing conditions.The plasma formation is well confined for low pulse energies,2 mJ,but higher pulse energies lead to the filamentation and break-up of the disruptions for conventional focusing,thereby decreasing the modification quality.In contrast,plasma induced by SSTF stays well confined to the focal plane,even for high pulse energies up to 8 mJ,preventing extended filaments,side branches or break-up of the disruptions.Furthermore,while conventional focusing leads to broadband supercontinuum generation,only marginal spectral broadening is observed using SSTF.These experimental findings are in excellent agreement with numerical simulations of the nonlinear pulse propagation and interaction processes.Therefore,SSTF appears to be a powerful tool to control the processing of transparent materials,e.g.,for precise ophthalmic fs-surgery.
文摘The construction industry is facing a big challenge in reducing the burden it is putting on the environment. There is an urgent need to develop and use eco-efficient construction materials with proper functional performance, a low carbon footprint and a less adverse impact on the environment. Nanotechnology is a new and very promising technology that helps fulfil the need for more environmentally friendly construction materials.
文摘The research achievements of solidification theories and technologies in the last decades are reviewed with the stresses on some new development in the recent years. Some new interesting areas emerged in the last years are also pointed out.
基金supported by the National Basic Research and Development Program of China (No. 2010CB732004)the joint funding of the National Natural Science Foundation and Shanghai Baosteel Group Corporation of China (No. 51074177)
文摘Because there is neither waste rock nor mill tailings in the gypsum mine, and the buildings on the goaf of gypsum mine are needed to be protected, the research proposed the scheme of the clay filling technology. Gypsum, cement, lime and water glass were used as adhesive, and the strength of different material ratios were investigated in this study. The influence factors of clay strength were obtained in the order of cement, gypsum, water glass and lime. The results show that the cement content is the determinant influence factor, and gypsum has positive effects, while the water glass can enhance both clay strength and the fluidity of the filing slurry. Furthermore, combining chaotic optimization method with neural network, the optimal ratio of composite cementing agent was obtained. The results show that the optimal ratio of water glass, cement, lime and clay (in quality) is 1.17:6.74:4.17:87.92 in the process of bottom self-flow filling, while the optimal ratio is 1.78:9.58:4.71:83.93 for roof-contacted filling. A novel filling process to fill in gypsum mine goaf with clay is established. The engineering practice shows that the filling cost is low, thus, notable economic benefit is achieved.
文摘The First Pacific Rim International Confer-ence on Advanced Materials and Processing(PRICM-1)organized by The Chinese Society ofMetals(CSM),and co-sponsored by the Japan In-stitute of Metals(JIM),the Korean Institute ofMetals(KIM)and The Mineral,Metals & Materi-als Society of the United States(TMS),was held inShangri-La Hotel,Hangzhou,China on June24-27,1992.It was the first large international conference
文摘Ti1Al2O3 Functionally Gradient Material (FGM) was prepared by an explosive compaction/SHS process. Ten sheets of the compounding powder were laminated and pressed to get a green body of FGM. It was then compacted explosively By burying the explosive compaction body into a stoichiometric Al/TiO2 mixture and igniting the combustion of the stoichiometric Al/TiO2 mixture, the SHS reaction of the explosive compaction body was initiated by the heat released from the combustion of the stoichiometric Al/TiO2 mixture. In this way, Ti/Al2O3 FGM was synthesized. The adiabatic temperatures of each gradient layer were calculated when the preheating temperatures were 298 K and 1173 K, respectively The microstructure, composition and properties of Ti/Al2O3 FGM and the reaction mechanism of each gradient layer were studied. It was found that Ti/Al2O3 FGM prepared by the explosive compaction/SHS process had a high density and a high microhardness. Its structure, composition and properties showed apparent gradient distribution. The structure of the standard stoichiometric ratio gradient layer of FGM was a network structure. Its reaction mode could be described as follows: Al powder melted first, then the molten Al penetrated into the TiO2 zone and reacted with TiO2, and big pores were left in the original positions of Al powder. The reaction of gradient layers with the addition of Al3O3 as diluents was similar to that of the standard stoichiometric ratio gradient layer, so were their structure and composition. However, the reaction of gradient layers with the addition of Ti as diluents was more complex and the composition deviated slightly from the designed one
文摘A new concept named computational comminution is proposed in thispaper, which is different from the traditional studies on materialsprocessing procedure such as the study based on theoretic models, thestudy based on experiment models, which is based on informationmodels. Some key technologies applied to mate- rials processingprocedure such as artificial neural networks, fuzzy sets, geneticalgorithms and visualization techn- ology are also presented, and afusing methodology of these new technologies is studied. Applicationin the cement grinding process of Horomill shows that results in thispaper are efficient.
文摘The Joint Conference Organizing Committee of The Chinese Society of Metals(CSM),The Japan Insti-tute of Metals(JIM),The Korean Institute of Metals(KIM)and The Minerals,Metals & Materials Society(TMS)announces The First Pacific Rim International Conference on Advanced Materials and Processing(PRICM-1)which will be held in Hangzhou,China,in the last week of June,1992 lasting about four days.It is agreed that the PRICM-1 will be organized by The Chinese Society of Metals.
文摘A dvanced Metallic Materials Research and Processing Technology Center was found in December 1998. As a unit under The College of Mechanical Engineering, the Center is an expansion of the former Cast and Composite Materials Research Group, which was found in the early eighties of last century. The Center is focusing in the basic and applied research, and development of advanced metallic materials and their processing technology. It also functions as an organization
文摘Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.
文摘Editorial Policy Asian Journal of Traditional Medicines is an international journal devoted to the advancement of research on traditional medicines.The followed areas are covered:scientific and technological developments and research achievements in the fields of traditional medicine resources,medicinal material processing,pharmacognosy,natural medicinal chemistry,quality control,pharmacology,pharmacy,and clinical efficacy.It has columns for monographs,reviews,full research articles,short articles,newsletters and clinical case reports of traditional Chinese medicines.