The curriculum“Woven Fabric Structure Design and Application”is the core curriculum of textile majors in higher vocational colleges,which plays a very important role in the cultivation of students’vocational abilit...The curriculum“Woven Fabric Structure Design and Application”is the core curriculum of textile majors in higher vocational colleges,which plays a very important role in the cultivation of students’vocational ability and professional quality.The curriculum reform of“Woven Fabric Structure Design and Application”through the deep cooperation of industry-college partnerships,the comprehensive analysis of the major training objectives and graduation requirements,the redesign of the curriculum teaching content,the improvement of the teaching method and the examination method,has achieved good results.展开更多
Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative manage...Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative management of the construction process.BIM technology is applied to integrate information data during the construction of prefabricated structures,analyze the source of information data of construction projects,and build a digital information model.BIM technology consists of information integration function,information data simulation,cross-region coordination and more.Therefore,this paper applies it to the process of prefabricated structure design,puts forward relevant technical research strategies,establishes relevant models,ensures the accuracy of drawing,and simulates the final construction effect according to the combination of arranged relevant parameters.展开更多
Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform f...Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform for fundamental science research and applications.Patterned structures based on lead halide perovskites have much more novel properties compared with their more commonly seen bulk-,micro-,and nano-crystals,such as improvement in antireflection,light-scattering effects,and light absorption,as a result of their adjustability of spatial distributions.However,there are many challenges yet to be resolved in this field,such as insufficient patterned resolution,imperfect crystal quality,complicated preparation process,and so on.To pave the way to solve these problems,we provide a systematic presentation of current methods for fabricating lead halide perovskite patterned structures,including thermal imprint,use of etching films,two-step vapor-phase growth,template-confined solution growth,and seed-assisted growth.Furthermore,the advantages and disadvantages of these methods are elaborated in detail.In addition,thanks to the extraordinary properties of lead halide perovskite patterned structures,a variety of potential applications in optics and optoelectronics of these structures are described.Lastly,we put forward existing challenges and prospects in this exciting field.展开更多
The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive mod...The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive modification, and performing fiber surface modification. As fabric composites, the weave structures play an important role in the mechanical and tribological performances of the liners. However, hardly any literature is available on the friction and wear behavior of such composites with different weave structures. In this paper, three weave structures (plain, twill 1/3 and satin 8/5) of hybrid Kevlar/PTFE fabric composites are selected and pin-on-flat linear reciprocating wear studies are done on a CETR tester under different pressures and different frequencies. The relationship between the tensile strength and the wear performance are studied. The morphologies of the worn surfaces under the typical test conditions are analyzed by means of scanning electron microscopy (SEM). The analysis results show that at 10 MPa, satin 8/5 performs the best in friction-reduction and antiwear performance, and plain is the worst. At 30 MPa, however, the antiwear performance is reversed and satin 8/5 does not even complete the 2 h wear test at 16 Hz. There is no clear evidence proving that the tensile strength has an influence on the wear performance. So the different tribological performance of the three weave structures of fabric composites may be attributed to the different PTFE proportions in the fabric surface and the different wear mechanisms. The fabric composites are divided into three regions: the lubrication region, the reinforced region and the bonding region. The major mechanisms are fatigue wear and the shear effects of the friction force in the lubrication region. In the reinforced region fiber-matrix de-bonding and fiber breakage are involved. The proposed research proposes a regional wear model and further indicates the wear process and the wear mechanism of fabric composites.展开更多
Nickel-based superalloy lattice sandwich structures present higher stiffness,higher strength and higher temperature resistance in comparison with other metals.In this study,the Kagome unit was adopted to design the la...Nickel-based superalloy lattice sandwich structures present higher stiffness,higher strength and higher temperature resistance in comparison with other metals.In this study,the Kagome unit was adopted to design the lattice sandwich structure and ProCAST software was used to simulate the filling and solidification processes of the nickel-based superalloy.Grain morphology and sizes of the nickel-based superalloy lattice sandwich structures were simulated by using of cellular automaton coupled with finite element model(CAFE),and indirect additive manufacture combining with investment casting were carried out to fabricate the nickel-based superalloy lattice sandwich structures.The calculated grain morphology and sizes are in good agreement with the experimental results.The grains are mainly equiaxed with an average size of about 500µm.The simulated results also show that the superheat of melting and the mold preheated temperature have significant influence on the grain size of the Kagome lattice sandwich structures,lower superheat of melting and mold preheated temperatures are encouraged to obtain the fine grains while assuring the integrity of the Kagome lattice sandwich structures for industrial application.展开更多
Natural dyestuff of luteolin was isolated and used to dye wool fabric in this paper. Ethanol extraction and high-speed countercurrent chromatography (HSCCC) were used to extract and purify the luteolin from the peanut...Natural dyestuff of luteolin was isolated and used to dye wool fabric in this paper. Ethanol extraction and high-speed countercurrent chromatography (HSCCC) were used to extract and purify the luteolin from the peanut shell, and the structure of the isolated luteolin was characterized with FTIR techniques. The interaction between dyestuff and fiber was preliminarily discussed through thermodynamic study and supramolecular structure simulation to explain the intrinsic reasons why the color fastness was low when luteolin was applied to dyeing wool fabric. The extraction condition and purification parameter were as follows: 65% ethanol, ratio of material to liquid 1:20, 80°C, 3 h, chloroform-methanol-water (4/3/2, V/V), 800 rmp/min, 2.0 Mkpa, 0.5 mL/ min and 280 nm. The results of dyeing thermodynamics showed that the sorption isotherm of luteolin on wool fabric was consistent with Nernst model and similar to the disperse dyestuff. With molecular simulation, luteolin and glycin composed 8 stable complexes whose Laplacian values all were greater than 0, which suggested typical hydrogen bonds existing. The complex with three hydrogen bonds was proved the most stable. Both studies on thermodynamics and supramolecular simulation revealed that luteolin on wool fabric mainly depended on the weak hydrogen bonds interaction that determined the low dyefastness.展开更多
This article has been directed to Environment Protection Technology with the purpose of providing a new instrument designed and developed to measure filtration efficiency through the relationship between clean cloth f...This article has been directed to Environment Protection Technology with the purpose of providing a new instrument designed and developed to measure filtration efficiency through the relationship between clean cloth fabric structural parameters, dust parameters, and test measuring variables. Fabric samples used throughout the present study were woven cotton 100%, polyester 100% and cotton/polyester 50/50%. The warp count: 30/2 for all fabric samples, the weft count is 9/1;12/1;and 20/1. The weave of satin, basket, and twill is 3/1 with four different picks/cm to produce the fabrics with the same cover factor. For dust separation fabrics range in weight from “300 - 450 g/m<sup>2</sup>” with an air permeability of “100 - 300 l/d m<sup>2</sup>·min” at “196.2 Pa” (20 mm WG) as specified in DIN 53887. Air permeability through fabrics depends entirely on the sieving percent of the surface of the fabric, which is partly the pores and partly the permeability through the yarns, which are the basic elements of a fabric. The results showed that dust capturing depends entirely on air permeability, which is related to fabric weave structure and fabric material at specified testing and measuring variables.展开更多
Influence of fabric geometrical parameters,including the number of filling yarns per 10 cm,yarn twist and fiber type,on bonding of the fabric reinforced cement composites is studied by fabric pull-out test and SEM mic...Influence of fabric geometrical parameters,including the number of filling yarns per 10 cm,yarn twist and fiber type,on bonding of the fabric reinforced cement composites is studied by fabric pull-out test and SEM microstructure analysis.The results show that the bonding strength increase with the increase of the number of filling yarns per 10 cm in the range of this study.But the influence of fabric count on the interfacial bonding is dual and there is a critical value.The twist of yarns has a little effect on the bonding strength and interfacial bonding behaves of nylon fabric reinforced cement composites.There is an optimum twist range.Within this range,the bonding strength increase slowly with the increase of yarn twist.Beyond this range,it is versus.The bonding strength is strongly affected by the fabric character.The bonding between the nylon fiber fabric and cement is good;that of between glass fiber fabric and cement is moderate and that of between the carbon fiber fabric and cement is poor.展开更多
Using In(NO3)3·5H2O and acetylacetone as raw materials and anhydrous SnCl4 as dopant, the transparent conducting indium tin oxide(ITO) films were prepared by sol-gel and dip-coating technique. The phase transform...Using In(NO3)3·5H2O and acetylacetone as raw materials and anhydrous SnCl4 as dopant, the transparent conducting indium tin oxide(ITO) films were prepared by sol-gel and dip-coating technique. The phase transformation, structure properties and physical properties (sheet resistance and transmittance) of the films were investigated by DTA-TG, XRD, SEM, four-probe method and UV-Vis spectrometry. The results indicate that it is feasible to fabricate ITO films on the quartz substrates by sol-gel technique, and the ITO films are formed by accumulating of particles with the size of several decades of nanometers. The prepared ITO film has cubic bixbyite structure, and (111) is its preferred plane. After five-times dip-coating, the ITO film has a thickness less than 150 nm, a sheet resistance of 110Ω/□, a resistivity of 1.65×10-3 Ω·cm and a transparency of 90%.展开更多
The development of efficient perovskite light-emitting diodes(PeLEDs)relies strongly on the fabrication of perovskite films with rationally designed structures(grain size,composition,surface,etc.).Therefore,an underst...The development of efficient perovskite light-emitting diodes(PeLEDs)relies strongly on the fabrication of perovskite films with rationally designed structures(grain size,composition,surface,etc.).Therefore,an understanding of structure-performance relationships is of vital importance for developing high-performance perovskite devices,particularly for devices with in-situ fabricated perovskite nanocrystal films.In this study,we reveal the vertical structure of an in-situ fabricated quasi-two-dimensional perovskite film.By combining time-of-flight secondary ion mass spectrometry,energy dispersive spectroscopy,grazing incidence wide-angle X-ray scattering(GIWAXS),and low-temperature photoluminescence spectra,we illustrate that the resulting in-situ fabricated DPPA_(2)Cs_(n-1)Pb_(n)(Br_(0.3)I_(0.7))_(3n+1)(DPPA^(+):3,3-diphenylpropylammonium)film has a gradient structure with a very thin layer of ligands on the surface,predominantly small-n domains at the top,and predominantly large-n domains at the bottom owing to the solubility difference of the precursors.In addition,GIWAXS measurements show that the domain of n=2 on the top layer has an ordered in-plane alignment.Based on the understanding of the film structure,we developed an in-situ fabrication process with ligand exchange to achieve efficient pure red PeLEDs at 638 nm with an average external quantum efficiency(EQE)of 7.4%.The optimized device had a maximum luminance of 623 cd/m^(2) with a peak EQE of 9.7%.展开更多
Light-framed timber structure(LTS)buildings have been highly valued in recent years due to their low-carbon characteristics.However,the applicability of the building envelope is closely related to indoor and outdoor c...Light-framed timber structure(LTS)buildings have been highly valued in recent years due to their low-carbon characteristics.However,the applicability of the building envelope is closely related to indoor and outdoor conditions.The hot summer and cold winter(HSCW)climate zone in China has high humidity and great temperature variation throughout the year,resulting in distinct outdoor environments in different seasons.The indoor environment is greatly affected by energy-consumption patterns and window-opening habits,which largely depend upon the regulation operations of occupants.All these interrelated factors lead to extremely complex boundary conditions on each side of the building envelope.Whether the structures of LTS buildings are applicable in this climate zone,therefore,needs to be carefully considered.In this study,two LTS buildings with different envelopes were established in Haining,China,situated in the HSCW climate zone,and selected as the study objects.Different operation modes were adopted to create a variety of indoor environments.Under each condition,the processes of heat and moisture transfer within the building envelopes and the indoor environment were monitored and compared.The comparison indicated that the building envelope with high moisture storage and insulation ability maintained a relatively stable indoor environment,especially when the environment changed abruptly.Conversely,if the outdoor environment was equable(e.g.,relative humidity within the range of 30%–60%)or intermittent energy consumption modes were adopted,the building envelope with a low thermal inertia index and weak moisture-buffering ability performed better because it enabled a faster response of the indoor environment to air conditioning.Moreover,a high risk of moisture accumulation between the thermal insulation layer and other materials with a large water vapour transfer resistance factor was also identified,suggesting a higher requirement for the vapour insulation of the envelopes of LTS buildings.展开更多
Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the meth...Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the methods in defect controlcurrently face challenges with overly large operational areas and a lack of precision in targeting specific defects. Therefore,we propose a new method for the precise and universal defect healing of TMD materials, integrating real-time imaging withscanning transmission electron microscopy (STEM). This method employs electron beam irradiation to stimulate the diffusionmigration of surface-adsorbed adatoms on TMD materials grown by low-temperature molecular beam epitaxy (MBE),and heal defects within the diffusion range. This approach covers defect repairs ranging from zero-dimensional vacancydefects to two-dimensional grain orientation alignment, demonstrating its universality in terms of the types of samples anddefects. These findings offer insights into the use of atomic-level focused electron beams at appropriate voltages in STEMfor defect healing, providing valuable experience for achieving atomic-level precise fabrication of TMD materials.展开更多
Five parameters of fabric structure are selected to study the relationship between fabric structure and fabric air permeability by orthogonal test . The influencing rule and influencing order of these factors on air p...Five parameters of fabric structure are selected to study the relationship between fabric structure and fabric air permeability by orthogonal test . The influencing rule and influencing order of these factors on air permeability are obtained.展开更多
This paper proposes a novel method for analyzing a textile fabric structure to extract positional information regarding each yarn using three-dimensional X-ray computed tomography(3D CT) image.Positional relationship ...This paper proposes a novel method for analyzing a textile fabric structure to extract positional information regarding each yarn using three-dimensional X-ray computed tomography(3D CT) image.Positional relationship among the yarns can be reconstructed using the extracted yarn positional information.In this paper,a sequence of points on the center line of each yarn of the sample is defined as the yarn positional information,since the sequence can be regarded as the representative position of the yarn.The sequence is extracted by tracing the yarn.The yarn is traced by estimating the yarn center and direction and correlating the yarn part of the 3D CT image with a 3D yarn model,which is moved along the estimated yarn direction.The trajectory of the center of the yarn model corresponds to the positional information of the yarn.The application of the proposed method is shown by experimentally applying the proposed method to a 3D CT image of a double-layered woven fabric.Furthermore,the experimental results for a plain knitted fabric show that this method can be applied to even knitted fabrics.展开更多
Simple mechanical models of fabric and yarns during fabric bending have been built tosimulate the bending performance or the fabric. On these models, the relation between fab-ric bending modulus and structure paramete...Simple mechanical models of fabric and yarns during fabric bending have been built tosimulate the bending performance or the fabric. On these models, the relation between fab-ric bending modulus and structure parameters is discussed, and a theoretical equation isgiven to describe this relation. Experiments have been arranged to measure fabric bendingmodulus and structure parameters. It is found that the equation gives out rather satisfiedresults and can be used in practice after certain modification.展开更多
Will use the same number of positive and negative coil longitudinal organization of fabric is ta edge sex used in the work of the organization to warp fabric edge sex, between restrained knitting principle, design a k...Will use the same number of positive and negative coil longitudinal organization of fabric is ta edge sex used in the work of the organization to warp fabric edge sex, between restrained knitting principle, design a kind of weft basketwork weaving method, especially in weft knitting machine woven from has the edge of weft knitted fabric performance weaving method. In order to overcome the existing technology aims to make weft basketwork structure of a single organization, edge sex is bad, or can’t produce rich weft knitted fabric appearance of shortage, provide a resistance to edge weft knitted fabric weaving method.展开更多
The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time ...The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time of curing are the major influencing factors for concrete strength. Normal practice of curing is to wrap the concrete with jute woven fabric and spraying of water. The absorbency characteristics of different GSM (Gram per square meter) of woven and Non-woven fabric were studied. The Non-woven fabric absorbency is superior to woven fabric of same GSM by its three dimensional structure and high pore volume. The strength of concrete cured with Non- woven fabric is 2.1 N/mm2 higher than woven fabric of same 350 GSM. The difference in compressive strength of Non-woven fabric of 350 GSM and 750 GSM is 0.06 N/mm2 which is marginal.展开更多
Since the discovery of transition metal dichalcogenide(TMDC)nanoparticles(NPs)with the onion-like structure,many efforts have been made to develop their fabrication methods.Laser fabrication(LF)is one of the most prom...Since the discovery of transition metal dichalcogenide(TMDC)nanoparticles(NPs)with the onion-like structure,many efforts have been made to develop their fabrication methods.Laser fabrication(LF)is one of the most promising methods to prepare onion-structured TMDC(or OS-TMDC)NPs due to its green,flexible,and scalable syntheses.In this mini-review article,we systematically introduce various laser-induced OS-TMDC(especially the OS-MoS_(2))NPs,their formation mechanism,properties,and applications.The preparation routes mainly include laser ablation in liquids and atmospheres,and laser irradiation in liquids.The various formation mechanisms are then introduced based on the different preparation routes,to describe the formations of the corresponding OS-NPs.Finally,some interesting properties and novel applications of these NPs are briefly demonstrated,and a short outlook is also given.This review could help to understand the progress of the laser-induced OS-TMDC NPs and their applications.展开更多
2D and 3D submicron periodic structures are first fabricated by red-induced photopolymerization using a common 635 nm semiconductor laser and specially developed red-sensitive polymer material. The principle of this n...2D and 3D submicron periodic structures are first fabricated by red-induced photopolymerization using a common 635 nm semiconductor laser and specially developed red-sensitive polymer material. The principle of this new photo- polymer material fabrication is explained and the absorption spectra of the material are measured. This fabrication technique allows a deeper penetration into volume and larger interference irradiation area which is more than 1 cm2. The optical design, theoretical calculations and experimental results including diffraction patterns verifying the forma- tion of periodic structures are presented. Compared with other fabrication technologies using high-power lasers, this approach has greatly reduced the demand for laser apparatus. Therefore, it is much more accessible to most. laboratories and potentially usable in holographic fabrication of photonic crystals and devices in micro electro-mechanical systems (MEMS).展开更多
文摘The curriculum“Woven Fabric Structure Design and Application”is the core curriculum of textile majors in higher vocational colleges,which plays a very important role in the cultivation of students’vocational ability and professional quality.The curriculum reform of“Woven Fabric Structure Design and Application”through the deep cooperation of industry-college partnerships,the comprehensive analysis of the major training objectives and graduation requirements,the redesign of the curriculum teaching content,the improvement of the teaching method and the examination method,has achieved good results.
文摘Building information modeling(BIM)technology simulates visual information data by integrating the information data of construction projects.The presentation of information parameters allows better collaborative management of the construction process.BIM technology is applied to integrate information data during the construction of prefabricated structures,analyze the source of information data of construction projects,and build a digital information model.BIM technology consists of information integration function,information data simulation,cross-region coordination and more.Therefore,this paper applies it to the process of prefabricated structure design,puts forward relevant technical research strategies,establishes relevant models,ensures the accuracy of drawing,and simulates the final construction effect according to the combination of arranged relevant parameters.
基金The authors acknowledge support from the National Natural Science Foundation of China(Grant Nos.51902061 and 62090031).
文摘Lead halide perovskites have received considerable attention from researchers over the past several years due to their superior optical and optoelectronic properties,because of which they can be a versatile platform for fundamental science research and applications.Patterned structures based on lead halide perovskites have much more novel properties compared with their more commonly seen bulk-,micro-,and nano-crystals,such as improvement in antireflection,light-scattering effects,and light absorption,as a result of their adjustability of spatial distributions.However,there are many challenges yet to be resolved in this field,such as insufficient patterned resolution,imperfect crystal quality,complicated preparation process,and so on.To pave the way to solve these problems,we provide a systematic presentation of current methods for fabricating lead halide perovskite patterned structures,including thermal imprint,use of etching films,two-step vapor-phase growth,template-confined solution growth,and seed-assisted growth.Furthermore,the advantages and disadvantages of these methods are elaborated in detail.In addition,thanks to the extraordinary properties of lead halide perovskite patterned structures,a variety of potential applications in optics and optoelectronics of these structures are described.Lastly,we put forward existing challenges and prospects in this exciting field.
基金supported by National Defense Foundation of China
文摘The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive modification, and performing fiber surface modification. As fabric composites, the weave structures play an important role in the mechanical and tribological performances of the liners. However, hardly any literature is available on the friction and wear behavior of such composites with different weave structures. In this paper, three weave structures (plain, twill 1/3 and satin 8/5) of hybrid Kevlar/PTFE fabric composites are selected and pin-on-flat linear reciprocating wear studies are done on a CETR tester under different pressures and different frequencies. The relationship between the tensile strength and the wear performance are studied. The morphologies of the worn surfaces under the typical test conditions are analyzed by means of scanning electron microscopy (SEM). The analysis results show that at 10 MPa, satin 8/5 performs the best in friction-reduction and antiwear performance, and plain is the worst. At 30 MPa, however, the antiwear performance is reversed and satin 8/5 does not even complete the 2 h wear test at 16 Hz. There is no clear evidence proving that the tensile strength has an influence on the wear performance. So the different tribological performance of the three weave structures of fabric composites may be attributed to the different PTFE proportions in the fabric surface and the different wear mechanisms. The fabric composites are divided into three regions: the lubrication region, the reinforced region and the bonding region. The major mechanisms are fatigue wear and the shear effects of the friction force in the lubrication region. In the reinforced region fiber-matrix de-bonding and fiber breakage are involved. The proposed research proposes a regional wear model and further indicates the wear process and the wear mechanism of fabric composites.
基金financially supported by the National Science and Technology Major Project of China(No.2017ZA04014001)the Natural Science Foundation of Liaoning Province of China(Nos.2019-ZD-0997,20170540890)the Technology Development Fund of China Academy of Machinery Science and Technology(No.170217ZS01)
文摘Nickel-based superalloy lattice sandwich structures present higher stiffness,higher strength and higher temperature resistance in comparison with other metals.In this study,the Kagome unit was adopted to design the lattice sandwich structure and ProCAST software was used to simulate the filling and solidification processes of the nickel-based superalloy.Grain morphology and sizes of the nickel-based superalloy lattice sandwich structures were simulated by using of cellular automaton coupled with finite element model(CAFE),and indirect additive manufacture combining with investment casting were carried out to fabricate the nickel-based superalloy lattice sandwich structures.The calculated grain morphology and sizes are in good agreement with the experimental results.The grains are mainly equiaxed with an average size of about 500µm.The simulated results also show that the superheat of melting and the mold preheated temperature have significant influence on the grain size of the Kagome lattice sandwich structures,lower superheat of melting and mold preheated temperatures are encouraged to obtain the fine grains while assuring the integrity of the Kagome lattice sandwich structures for industrial application.
文摘Natural dyestuff of luteolin was isolated and used to dye wool fabric in this paper. Ethanol extraction and high-speed countercurrent chromatography (HSCCC) were used to extract and purify the luteolin from the peanut shell, and the structure of the isolated luteolin was characterized with FTIR techniques. The interaction between dyestuff and fiber was preliminarily discussed through thermodynamic study and supramolecular structure simulation to explain the intrinsic reasons why the color fastness was low when luteolin was applied to dyeing wool fabric. The extraction condition and purification parameter were as follows: 65% ethanol, ratio of material to liquid 1:20, 80°C, 3 h, chloroform-methanol-water (4/3/2, V/V), 800 rmp/min, 2.0 Mkpa, 0.5 mL/ min and 280 nm. The results of dyeing thermodynamics showed that the sorption isotherm of luteolin on wool fabric was consistent with Nernst model and similar to the disperse dyestuff. With molecular simulation, luteolin and glycin composed 8 stable complexes whose Laplacian values all were greater than 0, which suggested typical hydrogen bonds existing. The complex with three hydrogen bonds was proved the most stable. Both studies on thermodynamics and supramolecular simulation revealed that luteolin on wool fabric mainly depended on the weak hydrogen bonds interaction that determined the low dyefastness.
文摘This article has been directed to Environment Protection Technology with the purpose of providing a new instrument designed and developed to measure filtration efficiency through the relationship between clean cloth fabric structural parameters, dust parameters, and test measuring variables. Fabric samples used throughout the present study were woven cotton 100%, polyester 100% and cotton/polyester 50/50%. The warp count: 30/2 for all fabric samples, the weft count is 9/1;12/1;and 20/1. The weave of satin, basket, and twill is 3/1 with four different picks/cm to produce the fabrics with the same cover factor. For dust separation fabrics range in weight from “300 - 450 g/m<sup>2</sup>” with an air permeability of “100 - 300 l/d m<sup>2</sup>·min” at “196.2 Pa” (20 mm WG) as specified in DIN 53887. Air permeability through fabrics depends entirely on the sieving percent of the surface of the fabric, which is partly the pores and partly the permeability through the yarns, which are the basic elements of a fabric. The results showed that dust capturing depends entirely on air permeability, which is related to fabric weave structure and fabric material at specified testing and measuring variables.
基金the Education Fund of Zhejiang Province(No.20030758)
文摘Influence of fabric geometrical parameters,including the number of filling yarns per 10 cm,yarn twist and fiber type,on bonding of the fabric reinforced cement composites is studied by fabric pull-out test and SEM microstructure analysis.The results show that the bonding strength increase with the increase of the number of filling yarns per 10 cm in the range of this study.But the influence of fabric count on the interfacial bonding is dual and there is a critical value.The twist of yarns has a little effect on the bonding strength and interfacial bonding behaves of nylon fabric reinforced cement composites.There is an optimum twist range.Within this range,the bonding strength increase slowly with the increase of yarn twist.Beyond this range,it is versus.The bonding strength is strongly affected by the fabric character.The bonding between the nylon fiber fabric and cement is good;that of between glass fiber fabric and cement is moderate and that of between the carbon fiber fabric and cement is poor.
文摘Using In(NO3)3·5H2O and acetylacetone as raw materials and anhydrous SnCl4 as dopant, the transparent conducting indium tin oxide(ITO) films were prepared by sol-gel and dip-coating technique. The phase transformation, structure properties and physical properties (sheet resistance and transmittance) of the films were investigated by DTA-TG, XRD, SEM, four-probe method and UV-Vis spectrometry. The results indicate that it is feasible to fabricate ITO films on the quartz substrates by sol-gel technique, and the ITO films are formed by accumulating of particles with the size of several decades of nanometers. The prepared ITO film has cubic bixbyite structure, and (111) is its preferred plane. After five-times dip-coating, the ITO film has a thickness less than 150 nm, a sheet resistance of 110Ω/□, a resistivity of 1.65×10-3 Ω·cm and a transparency of 90%.
基金supported by the National Natural Science Foundation of China(61735004).
文摘The development of efficient perovskite light-emitting diodes(PeLEDs)relies strongly on the fabrication of perovskite films with rationally designed structures(grain size,composition,surface,etc.).Therefore,an understanding of structure-performance relationships is of vital importance for developing high-performance perovskite devices,particularly for devices with in-situ fabricated perovskite nanocrystal films.In this study,we reveal the vertical structure of an in-situ fabricated quasi-two-dimensional perovskite film.By combining time-of-flight secondary ion mass spectrometry,energy dispersive spectroscopy,grazing incidence wide-angle X-ray scattering(GIWAXS),and low-temperature photoluminescence spectra,we illustrate that the resulting in-situ fabricated DPPA_(2)Cs_(n-1)Pb_(n)(Br_(0.3)I_(0.7))_(3n+1)(DPPA^(+):3,3-diphenylpropylammonium)film has a gradient structure with a very thin layer of ligands on the surface,predominantly small-n domains at the top,and predominantly large-n domains at the bottom owing to the solubility difference of the precursors.In addition,GIWAXS measurements show that the domain of n=2 on the top layer has an ordered in-plane alignment.Based on the understanding of the film structure,we developed an in-situ fabrication process with ligand exchange to achieve efficient pure red PeLEDs at 638 nm with an average external quantum efficiency(EQE)of 7.4%.The optimized device had a maximum luminance of 623 cd/m^(2) with a peak EQE of 9.7%.
基金supported by the National Natural Science Foundation of China(No.51978623).
文摘Light-framed timber structure(LTS)buildings have been highly valued in recent years due to their low-carbon characteristics.However,the applicability of the building envelope is closely related to indoor and outdoor conditions.The hot summer and cold winter(HSCW)climate zone in China has high humidity and great temperature variation throughout the year,resulting in distinct outdoor environments in different seasons.The indoor environment is greatly affected by energy-consumption patterns and window-opening habits,which largely depend upon the regulation operations of occupants.All these interrelated factors lead to extremely complex boundary conditions on each side of the building envelope.Whether the structures of LTS buildings are applicable in this climate zone,therefore,needs to be carefully considered.In this study,two LTS buildings with different envelopes were established in Haining,China,situated in the HSCW climate zone,and selected as the study objects.Different operation modes were adopted to create a variety of indoor environments.Under each condition,the processes of heat and moisture transfer within the building envelopes and the indoor environment were monitored and compared.The comparison indicated that the building envelope with high moisture storage and insulation ability maintained a relatively stable indoor environment,especially when the environment changed abruptly.Conversely,if the outdoor environment was equable(e.g.,relative humidity within the range of 30%–60%)or intermittent energy consumption modes were adopted,the building envelope with a low thermal inertia index and weak moisture-buffering ability performed better because it enabled a faster response of the indoor environment to air conditioning.Moreover,a high risk of moisture accumulation between the thermal insulation layer and other materials with a large water vapour transfer resistance factor was also identified,suggesting a higher requirement for the vapour insulation of the envelopes of LTS buildings.
基金the Beijing Natural Science Foundation(Grant Nos.JQ24010 and Z220020)the Fundamental Research Funds for the Central Universities,and the National Natural Science Foundation of China(Grant No.52273279)Project supported by the Electron Microscopy Laboratory of Peking University,China for the use of Nion U-HERMES200 scanning transmission electron microscopy.We thank Materials Processing and Analysis Center,Peking University,for assistance with TEM characterization.The electron microscopy work was through a user project at Center of Oak Ridge National Laboratory(ORNL)for Nanophase Materials Sciences(CNMS),which is a DOE Office of Science User Facility.
文摘Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the methods in defect controlcurrently face challenges with overly large operational areas and a lack of precision in targeting specific defects. Therefore,we propose a new method for the precise and universal defect healing of TMD materials, integrating real-time imaging withscanning transmission electron microscopy (STEM). This method employs electron beam irradiation to stimulate the diffusionmigration of surface-adsorbed adatoms on TMD materials grown by low-temperature molecular beam epitaxy (MBE),and heal defects within the diffusion range. This approach covers defect repairs ranging from zero-dimensional vacancydefects to two-dimensional grain orientation alignment, demonstrating its universality in terms of the types of samples anddefects. These findings offer insights into the use of atomic-level focused electron beams at appropriate voltages in STEMfor defect healing, providing valuable experience for achieving atomic-level precise fabrication of TMD materials.
文摘Five parameters of fabric structure are selected to study the relationship between fabric structure and fabric air permeability by orthogonal test . The influencing rule and influencing order of these factors on air permeability are obtained.
基金Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science(2006-No.18800064)
文摘This paper proposes a novel method for analyzing a textile fabric structure to extract positional information regarding each yarn using three-dimensional X-ray computed tomography(3D CT) image.Positional relationship among the yarns can be reconstructed using the extracted yarn positional information.In this paper,a sequence of points on the center line of each yarn of the sample is defined as the yarn positional information,since the sequence can be regarded as the representative position of the yarn.The sequence is extracted by tracing the yarn.The yarn is traced by estimating the yarn center and direction and correlating the yarn part of the 3D CT image with a 3D yarn model,which is moved along the estimated yarn direction.The trajectory of the center of the yarn model corresponds to the positional information of the yarn.The application of the proposed method is shown by experimentally applying the proposed method to a 3D CT image of a double-layered woven fabric.Furthermore,the experimental results for a plain knitted fabric show that this method can be applied to even knitted fabrics.
文摘Simple mechanical models of fabric and yarns during fabric bending have been built tosimulate the bending performance or the fabric. On these models, the relation between fab-ric bending modulus and structure parameters is discussed, and a theoretical equation isgiven to describe this relation. Experiments have been arranged to measure fabric bendingmodulus and structure parameters. It is found that the equation gives out rather satisfiedresults and can be used in practice after certain modification.
文摘Will use the same number of positive and negative coil longitudinal organization of fabric is ta edge sex used in the work of the organization to warp fabric edge sex, between restrained knitting principle, design a kind of weft basketwork weaving method, especially in weft knitting machine woven from has the edge of weft knitted fabric performance weaving method. In order to overcome the existing technology aims to make weft basketwork structure of a single organization, edge sex is bad, or can’t produce rich weft knitted fabric appearance of shortage, provide a resistance to edge weft knitted fabric weaving method.
文摘The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time of curing are the major influencing factors for concrete strength. Normal practice of curing is to wrap the concrete with jute woven fabric and spraying of water. The absorbency characteristics of different GSM (Gram per square meter) of woven and Non-woven fabric were studied. The Non-woven fabric absorbency is superior to woven fabric of same GSM by its three dimensional structure and high pore volume. The strength of concrete cured with Non- woven fabric is 2.1 N/mm2 higher than woven fabric of same 350 GSM. The difference in compressive strength of Non-woven fabric of 350 GSM and 750 GSM is 0.06 N/mm2 which is marginal.
基金the National Key Research and Development Program of China(Grant No.2017YFA0207101)the National Natural Science Foundation of China(Grant Nos.11974352 and 51771182)。
文摘Since the discovery of transition metal dichalcogenide(TMDC)nanoparticles(NPs)with the onion-like structure,many efforts have been made to develop their fabrication methods.Laser fabrication(LF)is one of the most promising methods to prepare onion-structured TMDC(or OS-TMDC)NPs due to its green,flexible,and scalable syntheses.In this mini-review article,we systematically introduce various laser-induced OS-TMDC(especially the OS-MoS_(2))NPs,their formation mechanism,properties,and applications.The preparation routes mainly include laser ablation in liquids and atmospheres,and laser irradiation in liquids.The various formation mechanisms are then introduced based on the different preparation routes,to describe the formations of the corresponding OS-NPs.Finally,some interesting properties and novel applications of these NPs are briefly demonstrated,and a short outlook is also given.This review could help to understand the progress of the laser-induced OS-TMDC NPs and their applications.
基金Projiect supported by the National Key Basic Research Special Fund of China (Grant No. 2004CB719805)the Ningbo Natural Science Foundation, China (Grant No. 2009A610011)
文摘2D and 3D submicron periodic structures are first fabricated by red-induced photopolymerization using a common 635 nm semiconductor laser and specially developed red-sensitive polymer material. The principle of this new photo- polymer material fabrication is explained and the absorption spectra of the material are measured. This fabrication technique allows a deeper penetration into volume and larger interference irradiation area which is more than 1 cm2. The optical design, theoretical calculations and experimental results including diffraction patterns verifying the forma- tion of periodic structures are presented. Compared with other fabrication technologies using high-power lasers, this approach has greatly reduced the demand for laser apparatus. Therefore, it is much more accessible to most. laboratories and potentially usable in holographic fabrication of photonic crystals and devices in micro electro-mechanical systems (MEMS).