Surface flashover is a gas-solid interface insulation failure that significantly jeopardises the secure operation of advanced electronic,electrical,and spacecraft applications.Despite the widespread application of num...Surface flashover is a gas-solid interface insulation failure that significantly jeopardises the secure operation of advanced electronic,electrical,and spacecraft applications.Despite the widespread application of numerous material modification and structure optimisation technologies aimed at enhancing surface flashover performance,the influence mechanisms of the present technologies have yet to be systematically discussed and summarised.This review aims to introduce various material modification technologies while demonstrating their influence mechanisms on flashover performances by establishing relationships among‘microscopic structure-mesoscopic charge transport-macroscopic insulation failure’.Moreover,it elucidates the effects of chemical structure on surface trap parameters and surface charge transport concerning flashover performance.The review categorises and presents structure optimisation technologies that govern electric field distribution.All identified technologies highlight that achieving a uniform tangential electric field and reducing the normal electric field can effectively enhance flashover performance.Finally,this review proposes recommendations encompassing mathematical,chemical,evaluation,and manufacturing technologies.This systematic summary of current technologies,their influence mechanisms,and associated advantages and disadvantages in improving surface insulation performance is anticipated to be a pivotal component in flashover and future dielectric theory.展开更多
Silicon Carbide (SiC) wafers have been widely used in micro- and nano-devices due to their excellent optical and material properties. However, polishing SiC wafers has been challenging and inefficient, tending to caus...Silicon Carbide (SiC) wafers have been widely used in micro- and nano-devices due to their excellent optical and material properties. However, polishing SiC wafers has been challenging and inefficient, tending to cause significant surface crack and subsurface damage. This work proposed modifying SiC surface properties by ion implantation to improve machining efficiency, suppress surface crack, and reduce damage. High-energy ion implantation disrupted the SiC crystal lattice, reducing hardness and elastic modulus while increasing brittle-ductile transition depth, thus changing the removal mode from brittle fracture to plastic removal. Theoretical models of material removal rate and surface roughness were established for abrasive polishing of the SiC wafers. Polishing experiments were conducted on ion-implanted, modified SiC samples. The improvement mechanisms of ion implantation on surface damage, removal rate, morphology, and residual stress were investigated. The effect of ion implantation on the polished surface quality of SiC was investigated through orthogonal experiments. The results showed that ion implantation can significantly improve the average material removal rate of the SiC samples. Additionally, the ion-implanted samples had exhibited remarkable reductions in surface roughness, surface damage, and tensile residual stress.展开更多
Graphite offers several advantages as an anode material,including its low cost,high theoretical capacity,extended lifespan,and low Li+-intercalation potential.However,the performance of graphite-based lithium-ion batt...Graphite offers several advantages as an anode material,including its low cost,high theoretical capacity,extended lifespan,and low Li+-intercalation potential.However,the performance of graphite-based lithium-ion batteries(LIBs)is limited at low temperatures due to several critical challenges,such as the decreased ionic conductivity of liquid electrolyte,sluggish Li+desolvation process,poor Li+diffusivity across the interphase layer and bulk graphite materials.Various approaches have therefore been explored to address these challenges.On the basis of graphite anode and corresponding LIBs,this review herein offers a comprehensive analysis of the latest advances in electrolyte engineering and electrode modification.First,electrolyte engineering is discussed in detail,highlighting the design of new electrolyte formula with broad liquid temperature range,optimized solvation structure,and well-performed inorganic-rich solid electrolyte interface.The advances in material modification have been then depicted with the view of improving the solid bulk diffusion rate to show general strategies with excellent performance at low temperatures.Finally,the corresponding challenges and opportunities have also been outlined to shed light on viable strategies for developing efficient and reliable graphite anode and graphite-based LIBs under low-temperature scenarios.展开更多
This paper presents the surface temperature behavior of M42 high-speed tool steel samples during N+ implantation in an industrialized GLZ-100 metal-ion implantation machine. A detail study has been made on the paramet...This paper presents the surface temperature behavior of M42 high-speed tool steel samples during N+ implantation in an industrialized GLZ-100 metal-ion implantation machine. A detail study has been made on the parameters of N+ implantation. Optimized technical parameters have been presented. The microhardness of the sample surface implanted under these parameters has been increased by a factor of 2.3, and the wear-resistance has been improved by about 5.4 times. The research on the mechanism of surface modification of M42 steel by nitrogen ion implantation has also been made.展开更多
Changes of surface morphology following XeCI excimer laser irradiation were investigated for three engineering ceramic materials (Al2O3, Al2O3-SiC nanocomposite and Si3N4). Al2O3 and AI2O3-SiC nanocomposite samples ex...Changes of surface morphology following XeCI excimer laser irradiation were investigated for three engineering ceramic materials (Al2O3, Al2O3-SiC nanocomposite and Si3N4). Al2O3 and AI2O3-SiC nanocomposite samples exhibit a smooth rapid melt layer on the surface, and the formation of the metastabfe γ-Al2Oa was observed. A silicon-rich layer on the surface was formed after laser irradiation of Si3N4. The toughness K1c of the materials was measured by the indentation fracture method. After laser irradiation, the toughness of Al2O3, Al2O3-SiC nanocomposite and Si3N4 was improved to various degrees: Al2O3-SiC nanocomposite, 60% (max.); AI203, 40% (max.); Si3N4, 12% (max.).展开更多
The nanosecond(ns) pulsed nitrogen dielectric barrier discharge(DBD) is employed to enhance the hydrophilicity of polypropylene(PP) surface and improve its application effect.The discharge characteristics of the ns pu...The nanosecond(ns) pulsed nitrogen dielectric barrier discharge(DBD) is employed to enhance the hydrophilicity of polypropylene(PP) surface and improve its application effect.The discharge characteristics of the ns pulsed nitrogen DBD with different pulse rise times(from 50to 500 ns) are investigated by electrical and optical diagnostic methods and the discharge uniformity is quantitatively analyzed by image processing method.To characterize the surface hydrophilicity,the water contact angle(WCA) is measured,and the physical morphology and chemical composition of PP before and after modification are analyzed to explore the effect of plasma on PP surface.It is found that with increasing pulse rise time from 50 to 500 ns,DBD uniformity becomes worse,energy efficiency decreases from 20% to 10.8%,and electron density decrease from 6.6 × 10^(11)to 5.5 × 10^(11)cm^(-3).The tendency of electron temperature is characterized with the intensity ratio of N_(2)/N_(2)^(+)emission spectrum,which decreases from 17.4 to15.9 indicating the decreasing of T_(e) with increasing pulse rise time from 50 to 500 ns.The PP surface treated with 50 ns pulse rise time DBD has a lower WCA(~47°),while the WCA of PP treated with 100 to 500 ns pulse rise time DBD expands gradually(~50°–57°).According to the study of the fixed-point WCA values,the DBD-treated PP surface has superior uniformity under50 ns pulse rise time(3° variation) than under 300 ns pulse rise time(8° variation).After DBD treatment,the increased surface roughness from 2.0 to 9.8 nm and hydrophilic oxygencontaining groups on the surface,i.e.hydroxyl(-OH) and carbonyl(C=O) have played the significant role to improve the sample’s surface hydrophilicity.The short pulse voltage rise time enhances the reduced electric field strength(E/n) in the discharge space and improves the discharge uniformity,which makes relatively sufficient physical and chemical reactions have taken place on the PP surface,resulting in better treatment uniformity.展开更多
The surface modification of nanometer carbon material has been studied by using an Induced Dielectric Barrier Discharge Plasma device (IDBD). The experimental results show that with different work gases and different ...The surface modification of nanometer carbon material has been studied by using an Induced Dielectric Barrier Discharge Plasma device (IDBD). The experimental results show that with different work gases and different discharge conditions, the surface behaviors of carbon black can be changed according to needs, including the use of different functional groups and the change of the surface roughness of carbon particles etc., which increased the grinding and dispersion abilities in binder.展开更多
Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic con...Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic condition monitoring.However,the limitations of traditional vehicle energy harvesting speed bumps such as single functionality and heavy-shock on vehicles are not conducive to developing energy harvesting speed bumps for multi-functionalization,versatility and intelligence.In this work,a compact hybridized triboelectricelectromagnetic road energy harvester(CHREH)device is designed.The vehicle's wheels impact force drives the sliding plate movement and triggers the triboelectric generator(TENG)unit and electromagnetic generator(EMG)unit to produce electricity.The enhanced TENG built by multi-layer folded structure is assembled using rGO and surface-patterning modified polydimethylsiloxane(PDMS)compositefilm.Furthermore,the mechanism and electrical output performance of EMG and TENG are theoretically simulated and experimentally tested.Particularly,TENG unit achieved a peak power of 7.21 mW and the EMG unit reached a peak power of 0.74 mW at an excitation frequency of 5 Hz,in addition to the superior durability.Further,the demonstration of application of self-powered car warning and speed monitoring were conducted.The CHREH offers a feasible approach for selfpowered applications deployable to the low power consumption electronic devices and ITS.展开更多
The unique physiological characteristics and complexity of tumor,in addition to drug resistance result in traditional therapies,such as chemotherapy and radiotherapy,being unable to achieve complete elimination of can...The unique physiological characteristics and complexity of tumor,in addition to drug resistance result in traditional therapies,such as chemotherapy and radiotherapy,being unable to achieve complete elimination of cancer cells.Meanwhile,the emerging immunotherapy suffers from a low patient response rate.Bacterial therapies are highly targeted.Bacteria can penetrate deep into the tumor and show good tumor inhibition.However,natural bacteria have the limitation of high toxicity and inability to meet the demand for efficient therapeutics.Recent advances in synthetic biology and materials science relate to the safety and efficacy of bacterial therapeutics,promising to develop engineered bacteria with low toxicity and complex therapeutic functions.Engineered bacteria that express anticancer drug molecules can target the tumor region,synthesizing and releasing payloads in response to internal and external stimuli.This process leads to the regression of the tumor and the effective inhibition of recurrence.This review outlines the recent advancements in the field of engineered bacteria research,particularly focusing on their applications in anti-tumor therapy.It also includes the advantageous features and mechanisms of engineered bacteria therapy,synthetic biology modification methods,and future challenges and directions of engineered bacteria therapy.展开更多
Developments in ceria-based soot oxidation catalysts, especially during the last decade, are reviewed. Based on the com- parisons of the activity, durability and cost-efficiency of different soot oxidation catalysts, ...Developments in ceria-based soot oxidation catalysts, especially during the last decade, are reviewed. Based on the com- parisons of the activity, durability and cost-efficiency of different soot oxidation catalysts, four kinds of applicable ceria-based cata- lysts have been screened out, which are： （1） CexZrl-xO2 catalyst with high cerium content （x〉0.76）, （2） rare-earth metals （especially Pr） modified ceria, （3） transition metals （especially Mn and Cu） modified ceria, and （4） Ag/CeO2. Moreover, a general review of recent developments on the morphology-controlled ceria-based catalysts, as well as that on the soot oxidation mechanisms over different ceria-based catalysts, is also presented.展开更多
Researches about synthesis and modification of nylon 10T(PA10T)in domestic universities and scientific research institutions are reviewed in this paper.The results show that,due to the different performance requiremen...Researches about synthesis and modification of nylon 10T(PA10T)in domestic universities and scientific research institutions are reviewed in this paper.The results show that,due to the different performance requirements,PA10T is studied from the co-polymerization,blending modification and filling modification of these three aspects.Meanwhile,the existing problems are analyzed and the development prospect of PA10T is predicted.展开更多
The properties of high performance color hardener (HPCH) and the mechanism were studied.HPCH is a composite system, which is composed of cementitious and auxiliary cementing materials, composite additives, abrasion re...The properties of high performance color hardener (HPCH) and the mechanism were studied.HPCH is a composite system, which is composed of cementitious and auxiliary cementing materials, composite additives, abrasion resistance component (aggregate) and pigment. The porosity and pore structure of the material are obviously improved due to the activation, filling and adsorption of auxiliary cementing materials, thus resulting in a great increase of binding capacity for ions in HPCH and the obstacles of ion migrating.The density of material structure, bonding capacity of cementitious material to the abrasion-resisting component and the corrosion resistance are greatly and effectively improved by adding the auxiliary cementing materials and compound additives. According to the tests of dry shrinkage, sulphate resistance, chloride permeability and Ca(OH) 2 content distribution, the property superiority of HPCH is analyzed.The mechanism of materials modification of HPCH is explained from the microscopic point of view by testing the pore structure and pore distribution via the mercury intrusion pressure method.展开更多
A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assis...A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assisted synthesis. A suspension of the magnetic particles in water soluble organic solvent （methanol, ethanol, propanol, isopropyl alcohol, or acetone） was mixed with the material to be modified and then completely dried at elevated temperature. The magnetically modified materials were found to be stable in water suspension at least for 2 months.展开更多
基金National Natural Science Foundation of China,Grant/Award Number:52307166Natural Science Foundation of Heilongjiang Province,Grant/Award Number:LH2023E085+1 种基金Natural Science Foundation of Shandong Province,Grant/Award Number:ZR2023QE072State Key Laboratory of Electrical Insulation and Power Equipment,Grant/Award Number:EIPE23206。
文摘Surface flashover is a gas-solid interface insulation failure that significantly jeopardises the secure operation of advanced electronic,electrical,and spacecraft applications.Despite the widespread application of numerous material modification and structure optimisation technologies aimed at enhancing surface flashover performance,the influence mechanisms of the present technologies have yet to be systematically discussed and summarised.This review aims to introduce various material modification technologies while demonstrating their influence mechanisms on flashover performances by establishing relationships among‘microscopic structure-mesoscopic charge transport-macroscopic insulation failure’.Moreover,it elucidates the effects of chemical structure on surface trap parameters and surface charge transport concerning flashover performance.The review categorises and presents structure optimisation technologies that govern electric field distribution.All identified technologies highlight that achieving a uniform tangential electric field and reducing the normal electric field can effectively enhance flashover performance.Finally,this review proposes recommendations encompassing mathematical,chemical,evaluation,and manufacturing technologies.This systematic summary of current technologies,their influence mechanisms,and associated advantages and disadvantages in improving surface insulation performance is anticipated to be a pivotal component in flashover and future dielectric theory.
基金support from the China Postdoctoral Science Foundation(No.2023M742735)the Postdoctoral Fellowship Program of CPSF,China(No.GZC20232029)+5 种基金the National Natural Science Foundation of China(No.52475530)the Shaanxi Postdoctoral Science Foundation,China(No.2023BSHEDZZ175)the Innovation Capability Support Program of Shaanxi Province,China(No.2021TD-23)the Key Industrial Chain Core Technology Research Project in Xi’an,China(No.23LLRH0029)the Natural Science Basic Research Program of Shaanxi,China(No.2024JC-YBQN-0490)the Fundamental Research Funds for the Central Universities,China(No.ZYTS24023).
文摘Silicon Carbide (SiC) wafers have been widely used in micro- and nano-devices due to their excellent optical and material properties. However, polishing SiC wafers has been challenging and inefficient, tending to cause significant surface crack and subsurface damage. This work proposed modifying SiC surface properties by ion implantation to improve machining efficiency, suppress surface crack, and reduce damage. High-energy ion implantation disrupted the SiC crystal lattice, reducing hardness and elastic modulus while increasing brittle-ductile transition depth, thus changing the removal mode from brittle fracture to plastic removal. Theoretical models of material removal rate and surface roughness were established for abrasive polishing of the SiC wafers. Polishing experiments were conducted on ion-implanted, modified SiC samples. The improvement mechanisms of ion implantation on surface damage, removal rate, morphology, and residual stress were investigated. The effect of ion implantation on the polished surface quality of SiC was investigated through orthogonal experiments. The results showed that ion implantation can significantly improve the average material removal rate of the SiC samples. Additionally, the ion-implanted samples had exhibited remarkable reductions in surface roughness, surface damage, and tensile residual stress.
基金supported by the National Key Research and Development Program of China(2022YFB3803400)National Natural Science Foundation of China(22109028)+1 种基金Natural Science Foundation of Shanghai(22ZR1404400)Chenguang Program sponsored by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(19CG01).
文摘Graphite offers several advantages as an anode material,including its low cost,high theoretical capacity,extended lifespan,and low Li+-intercalation potential.However,the performance of graphite-based lithium-ion batteries(LIBs)is limited at low temperatures due to several critical challenges,such as the decreased ionic conductivity of liquid electrolyte,sluggish Li+desolvation process,poor Li+diffusivity across the interphase layer and bulk graphite materials.Various approaches have therefore been explored to address these challenges.On the basis of graphite anode and corresponding LIBs,this review herein offers a comprehensive analysis of the latest advances in electrolyte engineering and electrode modification.First,electrolyte engineering is discussed in detail,highlighting the design of new electrolyte formula with broad liquid temperature range,optimized solvation structure,and well-performed inorganic-rich solid electrolyte interface.The advances in material modification have been then depicted with the view of improving the solid bulk diffusion rate to show general strategies with excellent performance at low temperatures.Finally,the corresponding challenges and opportunities have also been outlined to shed light on viable strategies for developing efficient and reliable graphite anode and graphite-based LIBs under low-temperature scenarios.
文摘This paper presents the surface temperature behavior of M42 high-speed tool steel samples during N+ implantation in an industrialized GLZ-100 metal-ion implantation machine. A detail study has been made on the parameters of N+ implantation. Optimized technical parameters have been presented. The microhardness of the sample surface implanted under these parameters has been increased by a factor of 2.3, and the wear-resistance has been improved by about 5.4 times. The research on the mechanism of surface modification of M42 steel by nitrogen ion implantation has also been made.
文摘Changes of surface morphology following XeCI excimer laser irradiation were investigated for three engineering ceramic materials (Al2O3, Al2O3-SiC nanocomposite and Si3N4). Al2O3 and AI2O3-SiC nanocomposite samples exhibit a smooth rapid melt layer on the surface, and the formation of the metastabfe γ-Al2Oa was observed. A silicon-rich layer on the surface was formed after laser irradiation of Si3N4. The toughness K1c of the materials was measured by the indentation fracture method. After laser irradiation, the toughness of Al2O3, Al2O3-SiC nanocomposite and Si3N4 was improved to various degrees: Al2O3-SiC nanocomposite, 60% (max.); AI203, 40% (max.); Si3N4, 12% (max.).
基金supported by National Natural Science Foundation of China (Nos. 52037004, 51777091 and52250410350)Postgraduate Research&Practice Innovation Program of Jiangsu Province (No.KYCX22_1314)。
文摘The nanosecond(ns) pulsed nitrogen dielectric barrier discharge(DBD) is employed to enhance the hydrophilicity of polypropylene(PP) surface and improve its application effect.The discharge characteristics of the ns pulsed nitrogen DBD with different pulse rise times(from 50to 500 ns) are investigated by electrical and optical diagnostic methods and the discharge uniformity is quantitatively analyzed by image processing method.To characterize the surface hydrophilicity,the water contact angle(WCA) is measured,and the physical morphology and chemical composition of PP before and after modification are analyzed to explore the effect of plasma on PP surface.It is found that with increasing pulse rise time from 50 to 500 ns,DBD uniformity becomes worse,energy efficiency decreases from 20% to 10.8%,and electron density decrease from 6.6 × 10^(11)to 5.5 × 10^(11)cm^(-3).The tendency of electron temperature is characterized with the intensity ratio of N_(2)/N_(2)^(+)emission spectrum,which decreases from 17.4 to15.9 indicating the decreasing of T_(e) with increasing pulse rise time from 50 to 500 ns.The PP surface treated with 50 ns pulse rise time DBD has a lower WCA(~47°),while the WCA of PP treated with 100 to 500 ns pulse rise time DBD expands gradually(~50°–57°).According to the study of the fixed-point WCA values,the DBD-treated PP surface has superior uniformity under50 ns pulse rise time(3° variation) than under 300 ns pulse rise time(8° variation).After DBD treatment,the increased surface roughness from 2.0 to 9.8 nm and hydrophilic oxygencontaining groups on the surface,i.e.hydroxyl(-OH) and carbonyl(C=O) have played the significant role to improve the sample’s surface hydrophilicity.The short pulse voltage rise time enhances the reduced electric field strength(E/n) in the discharge space and improves the discharge uniformity,which makes relatively sufficient physical and chemical reactions have taken place on the PP surface,resulting in better treatment uniformity.
文摘The surface modification of nanometer carbon material has been studied by using an Induced Dielectric Barrier Discharge Plasma device (IDBD). The experimental results show that with different work gases and different discharge conditions, the surface behaviors of carbon black can be changed according to needs, including the use of different functional groups and the change of the surface roughness of carbon particles etc., which increased the grinding and dispersion abilities in binder.
基金supported by the National Natural Science Foundation of China(Grant Nos.12172127 and 12202262)the Key Project of Scientific Research Project of Hunan Provincial Department of Education(Grant Nos.22A0515 and 21A0463)the Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20231286).
文摘Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic condition monitoring.However,the limitations of traditional vehicle energy harvesting speed bumps such as single functionality and heavy-shock on vehicles are not conducive to developing energy harvesting speed bumps for multi-functionalization,versatility and intelligence.In this work,a compact hybridized triboelectricelectromagnetic road energy harvester(CHREH)device is designed.The vehicle's wheels impact force drives the sliding plate movement and triggers the triboelectric generator(TENG)unit and electromagnetic generator(EMG)unit to produce electricity.The enhanced TENG built by multi-layer folded structure is assembled using rGO and surface-patterning modified polydimethylsiloxane(PDMS)compositefilm.Furthermore,the mechanism and electrical output performance of EMG and TENG are theoretically simulated and experimentally tested.Particularly,TENG unit achieved a peak power of 7.21 mW and the EMG unit reached a peak power of 0.74 mW at an excitation frequency of 5 Hz,in addition to the superior durability.Further,the demonstration of application of self-powered car warning and speed monitoring were conducted.The CHREH offers a feasible approach for selfpowered applications deployable to the low power consumption electronic devices and ITS.
基金the National Natural Science Foundation of China(62375093 and 32422042)Technology Innovation Program of Hubei Province(2024BCB058)。
文摘The unique physiological characteristics and complexity of tumor,in addition to drug resistance result in traditional therapies,such as chemotherapy and radiotherapy,being unable to achieve complete elimination of cancer cells.Meanwhile,the emerging immunotherapy suffers from a low patient response rate.Bacterial therapies are highly targeted.Bacteria can penetrate deep into the tumor and show good tumor inhibition.However,natural bacteria have the limitation of high toxicity and inability to meet the demand for efficient therapeutics.Recent advances in synthetic biology and materials science relate to the safety and efficacy of bacterial therapeutics,promising to develop engineered bacteria with low toxicity and complex therapeutic functions.Engineered bacteria that express anticancer drug molecules can target the tumor region,synthesizing and releasing payloads in response to internal and external stimuli.This process leads to the regression of the tumor and the effective inhibition of recurrence.This review outlines the recent advancements in the field of engineered bacteria research,particularly focusing on their applications in anti-tumor therapy.It also includes the advantageous features and mechanisms of engineered bacteria therapy,synthetic biology modification methods,and future challenges and directions of engineered bacteria therapy.
基金supported by Ministry of Science and Technology of China(2013AA061902)the National Development and Reform Commission of China(2013012402)
文摘Developments in ceria-based soot oxidation catalysts, especially during the last decade, are reviewed. Based on the com- parisons of the activity, durability and cost-efficiency of different soot oxidation catalysts, four kinds of applicable ceria-based cata- lysts have been screened out, which are： （1） CexZrl-xO2 catalyst with high cerium content （x〉0.76）, （2） rare-earth metals （especially Pr） modified ceria, （3） transition metals （especially Mn and Cu） modified ceria, and （4） Ag/CeO2. Moreover, a general review of recent developments on the morphology-controlled ceria-based catalysts, as well as that on the soot oxidation mechanisms over different ceria-based catalysts, is also presented.
文摘Researches about synthesis and modification of nylon 10T(PA10T)in domestic universities and scientific research institutions are reviewed in this paper.The results show that,due to the different performance requirements,PA10T is studied from the co-polymerization,blending modification and filling modification of these three aspects.Meanwhile,the existing problems are analyzed and the development prospect of PA10T is predicted.
文摘The properties of high performance color hardener (HPCH) and the mechanism were studied.HPCH is a composite system, which is composed of cementitious and auxiliary cementing materials, composite additives, abrasion resistance component (aggregate) and pigment. The porosity and pore structure of the material are obviously improved due to the activation, filling and adsorption of auxiliary cementing materials, thus resulting in a great increase of binding capacity for ions in HPCH and the obstacles of ion migrating.The density of material structure, bonding capacity of cementitious material to the abrasion-resisting component and the corrosion resistance are greatly and effectively improved by adding the auxiliary cementing materials and compound additives. According to the tests of dry shrinkage, sulphate resistance, chloride permeability and Ca(OH) 2 content distribution, the property superiority of HPCH is analyzed.The mechanism of materials modification of HPCH is explained from the microscopic point of view by testing the pore structure and pore distribution via the mercury intrusion pressure method.
文摘A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assisted synthesis. A suspension of the magnetic particles in water soluble organic solvent （methanol, ethanol, propanol, isopropyl alcohol, or acetone） was mixed with the material to be modified and then completely dried at elevated temperature. The magnetically modified materials were found to be stable in water suspension at least for 2 months.
