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1.
The aim of this study is to develop a method with lower application temperature and a device structure to obtain reproducible photovoltaic textiles. Two different kinds of poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) solutions over a silver (Ag) layer was used as anode, a blend of poly(3-hexyl thiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) as light absorbing layer and a thin aluminum (Al)/Ag layer as semi-transparent cathode. These devices capable of generating electricity from sunlight were fabricated on polypropylene tapes that could be woven into a textile fabric. The short-circuit current density and power conversion efficiency of photovoltaic tapes were increased by using an Ag layer beneath the PEDOT:PSS electrode. The photovoltaic textile structure exhibited remarkable power conversion efficiency (0.29 %) by transmitting the light through the upper electrode. This approach may be used in industrial applications to develop photovoltaic textile materials.  相似文献   

2.
Scientists and engineers are increasingly turning to nature for inspiration. Light weight textile fabrics suitable for summer dress material were developed by imitating the branching structure of a plant in order to achieve high water absorption and transportation properties. The absorption property of the fabrics was characterized by using the Moisture Management Tester (MMT) and Transplanar Water Transport Tester (TWTT). The fabrics were analyzed using optical microscopes and Optical Contact Angle (OCA) tester to understand the structure as well as the absorption behavior of these fabrics. The results indicated that plant structured fabrics have a significant faster water absorption and wicking properties over conventional weave structures, makes them highly preferable for summer-wear.  相似文献   

3.
Electrospinning has been recognized as an efficient technique for the fabrication of neural tissue engineering scaffolds. Many approaches have been developed on material optimization, electrospinning techniques, and physical properties of scaffolds to produce a suitable scaffold for tissue engineering aspects. In this study, structural properties of scaffolds were promoted by controlling the speed of fiber collection without any post-processing. PLGA scaffolds, in two significantly different solution concentrations, were fabricated by the electrospinning process to produce scaffolds with the optimum nerve cell growth in a desired direction. The minimum, intermediate and maximum rate of fiber collection (0.4, 2.4, 4.8 m/s) formed Random, Aligned and Drown-aligned fibers, with various porosities and hydrophilicities. The scaffolds were characterized by fiber diameter, porosity, water contact angle and morphology. Human nerve cells were cultured on fiber substrates for seven days to study the effects of different scaffold structures on cell morphology and proliferation, simultaneously. The results of MTT assay, the morphology of cells and scaffold characterization recommend that the best structure to promote cell direction, morphology and proliferation is accessible in an optimized hydrophilicity and porosity of scaffolds, which was obtained at the collector linear speed of 2.4 m/s.  相似文献   

4.
稻根瘤状结构的发生发育及结构王洪隆,康玉庆,张存金(天津教育学院300020;1)现在地址:法国国家农业研究院蒙彼利埃研究中心,法国蒙彼利埃)Initiation,DevelopmentandStructureofRiceNodularStructu...  相似文献   

5.
In this study, multistitched woven nano composites were developed and their in-plane shear properties were characterized. The in-plane shear strength of unstitched structure was low compared to that of the unstitched/nano structures. However, the in-plane shear strength of unstitched structure was high compared to the machine stitched structures because of stitching and stitching yarn-matrix interfacial region. Additionally, the in-plane shear strength of machine stitched/nano composite structure was slightly high compared to the unstitched structure. The multistitched and multistitched/nano structures had limited delamination in their cross-sections. Their delamination regions were confined at a narrow area due to multistitching. This was considered that the developed multistitched/nano composites has better demage tolerance compared to unstitched composites.  相似文献   

6.
The aim of this study was to understand the warp and weft directional tensile properties of the developed two dimensional (2D) multistitched multilayer E-glass/polyester woven nano composites. It was found that the warp and weft directional specific tensile strength and modulus of unstitched structure were higher than those of the machine stitched and machine stitched/nano structures due to stitching caused filament breakages. When the nano silica material in the unstitched E-glass/polyester composite structure increased, the warp and weft directional specific tensile strength and the modulus of the unstitched/nano structures increased. The failure of warp and weft directional 2D unstitched and unstitched/nano woven E-glass/polyester composite structures had a complete delamination in their cross-sections. But, the failure of warp and weft directional 2D stitched and stitched/nano woven E-glass/polyester composite structures had a local delamination in their cross-sections and the failure was confined at a narrow area. The warp and weft directional specific damaged areas of unstitched structure were higher than those of the stitched and stitched/nano structures. Also, the warp and weft directional specific damaged areas of machine stitched structure were slightly higher than those of the machine stitched/nano structure. It could be concluded that the addition of nano silica to the stitched structures improved to their damage resistance.  相似文献   

7.
The aim of this study was to understand the ±45 ° directional off-axis tensile properties of the developed two dimensional (2D) multistitched multilayer E-glass/polyester woven composites. It was found that the off-axis tensile strength of the unstitched structure was slightly higher than those of the multistitched structures. The reason was that the multistitching process caused the filament breakages. It was also found that when the stitching direction and stitching density in structures increased, their off-axis tensile modulus decreased. Therefore, stitching directions, stitching density and stitching yarn on the composite structures were considered as important parameters. All structures under the off-axis tensile load had normal deformation, or angular deformation or shrinkage in width. In addition, both the normal deformation and the shrinkages in width occurred in most of the two and four directional stitched structures. On the other hand, four directional Kevlar® 129 yarn dense stitched E-glass/polyester structure showed only shrinkage in width after angular deformation. This could be considered as a new failure mode because of the multistitching. These results indicated that the stitching directions and density generally influenced the off-axis tensile properties of the multistitched E-glass/polyester woven composites.  相似文献   

8.
为研究添加维生素C对不同筋力小麦粉面包烘焙品质的改良效果,以师栾02-1、石优17、矮抗58和济麦22四个不同筋力小麦品种的面粉为材料,研究了维生素C对面包烘焙特性及面团流变性特性的影响。结果表明,添加维生素C对强筋品种师栾02-1和中筋品种矮抗58的面包体积有显著改良作用,而对4个品种的面包外观、面包芯色泽、面包芯质地和面包芯纹理结构均没有影响。添加维生素C对面团的弱化度和最大拉伸阻力等流变学特性的改良作用也因小麦品种而异,而且改良作用有限,不能改变小麦粉本身的加工属性。  相似文献   

9.
Biodegradable nanocomposites were prepared by mixing a polymer resin and layered silicates by the melt intercalation method. Internal structure of the nanocomposite was characterized by using the small angle X-ray scattering (SAXS) and transmission electron microscope (TEM). Nanocomposites having exfoliated and intercalated structures were obtained by employing two different organically modified nanoclays. Rheological properties in shear and extensional flows and biodegradability of nanocomposites were measured. In shear flow, shear thinning behavior and increased storage modulus were observed as the clay loading increased. In extensional flow, strain hardening behavior was observed in well dispersed system. Nanocomposites with the exfoliated structure had better biodegradability than nanocomposites with the intercalated structure or pure polymer.  相似文献   

10.
以携带相同Wxb基因的籼稻品种黄华占和扬稻6号为试验材料,系统分析了这2个优质籼稻品种的理化特性和淀粉精细结构.结果表明,黄华占稻米蛋白质含量显著低于扬稻6号,而表观直链淀粉含量高于扬稻6号,其他理化品质如胶稠度、总淀粉含量和碱消值两者无显著差异;黄华占稻米具有较高的糊化温度和热焓值.黄华占和扬稻6号稻米淀粉粘滞曲线较...  相似文献   

11.
The aim of this study was to understand the off-axis tensile properties of the developed two dimensional multistitched multilayer E-glass/polyester woven nano composites. It was found that the specific off-axis tensile strength of unstitched structure was higher than that of the machine stitched structure due to stitching caused filament breakages. But it was slightly lower than that of the machine stitched/nano structure. In addition, the specific off-axis tensile strength of machine stitched/nano composite structure was slightly higher than that of the machine stitched structure. When the nano silica material in the unstitched E-glass/polyester composite structure increased, the off-axis specific tensile strength and the modulus of the unstitched/nano structures increased whereas, the off-axis specific tensile strain of the unstitched/nano structures decreased. The damaged areas of the unstitched/nano structures increased, when the nano silica material in the unstitched E-glass/polyester woven composite structures increased. The failures under the off-axis tensile load of the stitched or stitched/nano structures were confined at narrow area due to the multistitching. On the other hand, it was observed that the off-axis failure of unstitched/nano or stitched/nano woven E-glass/polyester composite structures showed more brittle behavior.  相似文献   

12.
Konjac glucomannan (KGM), a dietary fiber, can be used to improve the quality of flour products. In this study, the effects of KGM at different concentrations on the water distribution, morphological, textural, thermal, and structural properties of wheat gluten were studied. KGM improved the physicochemical and structural properties of wheat gluten by changing the water holding capacity, secondary structure, and free sulfhydryl and disulfide bond contents. Scanning electron microscopy confirmed that KGM can evenly fill the network structure, affecting gluten network development. KGM exhibited no effect on moisture content; however, KGM decreased water mobility in wheat gluten. The increased thermal denaturation temperature indicates that KGM can improve the thermal stability of wheat gluten. Sharp changes in texture profile analysis (TPA) parameters were observed around 5% KGM, and elasticity and cohesiveness were optimal after the addition of 4% KGM. In addition, the secondary structure analysis indicated that α-helix and β-sheet structures increased. The addition of 5% KGM increased the content of disulfide bonds by 2.57-fold. Overall, the changes in gluten structure and properties suggest that wheat gluten could be improved the stability, functionality and water holding capacity of gluten by adding KGM.  相似文献   

13.
白兰开花过程中花被片结构的变化与释香机理   总被引:1,自引:0,他引:1  
应用光学显微镜和扫描电镜对白兰(Michelia laba DC.)花开放过程中花被片结构的变化进行了观察,并与成熟叶片的结构特征进行了比较,对白兰成熟花被片与成熟叶片的一些数量特征进行了测量,探讨了白兰花香气形成、挥发部位及挥发途径的结构基础。结果表明:(1)根据在花被片开展的不同时期的颗粒状细胞内含物的数量、形态及存在部位,推测白兰花被片颗粒状细胞内含物可能主要是香气释放前体物质。(2)白兰花被片与成熟叶片的解剖结构存在差异,表明花被片与叶片香气释放机理不一致。白兰花被片挥发性香气的前体物在基本薄壁组织细胞中产生,通过扩散作用输送到表皮细胞,最后通过表皮细胞的垂周壁、表皮细胞的细胞间隙、气孔释放出来。  相似文献   

14.
Alpaca fibers have some distinct properties such as softness and warmth, which have not been fully understood in combination with the fiber internal structures. In the present investigation, the internal structures of alpaca fibers have been closely examined under the scanning electron microscope (SEM), especially in the longitudinal direction. The results showed that numerous pigment granules reside loosely inside pockets in brown and dark-brown alpaca fibers. These pigment granules were mainly distributed inside the cortical cells, the medullation regions as well as underneath the cuticles. Their size in the brown alpaca fibers was smaller and more uniformly round than in the dark-brown fibers. These granules in colored alpaca fibers loosen the bundle of cortical cells, providing many crannies in the fibers which may contribute to the superior flexibility, warmth and softness of the fibers. Moreover, there are no heavy metal elements found in the granules. The mordant hydrogen peroxide bleaching employed could eliminate the pigment granules and create many nano-volumes for further dyeing of fibers into more attractive colors.  相似文献   

15.
This paper presents the effect of cross-sectional morphologies and composite structures of glass fiber felts on their corresponding acoustic properties. Glass fiber felts with random and layered cross-sectional structure are produced by centrifugal-spinneret-blow system. Acoustic properties are determined by a B&K impedance tube. The results show that sound transmission loss (STL) of glass fiber felts with layered cross-sectional structure exhibit greater than that with random cross-sectional structure. However, there is a little difference between the absorption coefficient values for random and layered cross-section. It means that glass fiber felts with layered cross-section are better to improve the sound insulation. With the increase of thickness, STLs of glass fiber felts with the same areal density do not increase monotonically due to the changing of porosity and characteristic impedances. Different glass fiber felts with layered cross-sectional structure are combined to form a variety of composite structures. It finds that assembly order of glass fiber felts have an effect on the total sound insulation. The large mismatch between the acoustic impedances causes multiple reflections leading to the best STL.  相似文献   

16.
Nanoparticles are gaining wider importance and increasing utility in many areas of engineering and technology. This investigative work is conducted to study the effect of incorporating basalt nano particles in composites with basalt/basalt and basalt/jute woven structures as reinforcement. The nanoparticles were developed from basalt, they were characterized and used for reinforcing composites of basalt and jute hybrid fabrics. The mechanical and thermo-mechanical properties of hybrid woven basalt reinforced epoxy composites were evaluated. Microscopic examination was carried out in order to analyze the internal structure and fractured surfaces. Interfacial characteristics, material morphology and failure was studied by use of Scanning Electron Microscope (SEM) and optical microscopy. Thermal stability was characterized by TGA. The results elaborated that the incorporation of basalt nanoparticles exhibited superior properties compared to the pure epoxy resin impregnated basalt fabric reinforced composites in terms of mechanical and thermal stability.  相似文献   

17.
The first chemical study of the Indo-Pacific dorid nudibranch Aldisa andersoni resulted in the isolation of five chlorinated phenyl-pyrrolyloxazoles belonging to the phorbazole series. Two new molecules, 9-chloro-phorbazole D and N1-methyl-phorbazole A, co-occurring with known phorbazoles A, B and D, have been characterized. Phorbazoles were found to be present mainly in the external part of the mollusc. The structures of the new compounds were determined by interpretation of spectroscopic data, mainly NMR and mass spectrometry and by comparison with the literature data. Evaluation of feeding-deterrence activity as well as in vitro growth inhibitory properties in human cancer cells was also carried out.  相似文献   

18.
In this contribution, three triphenylamine derivatives were synthesized and their spectral properties were investigated. Knoevenagel condensation of mono-, di-, and tri-aldehydes of triphenylamine with 1,3-indanedione yields D-π-A type dyes with push-pull chromophores. The absorption and luminescence properties of the dyes were discussed in terms of their electronic structures. The results of molecular orbital computer simulations, based on Material Studio, were found to provide a reasonable explanation for the observed spectral properties related to the push-pull features causing dramatic changes in UV-Vis absorption as well as in photoluminescence.  相似文献   

19.
为研究大豆Nodulin家族蛋白特性,在数据库Uniprot KB中下载大豆Nodulin蛋白序列,利用NCBI的BLAST程序进行同源序列比对筛选和Pfam数据库综合分析,确定14个大豆Nodulin家族蛋白,通过生物信息学方法对14个家族蛋白的基本理化性质、跨膜区域、模体、系统发育和蛋白结构等进行分析。结果显示:14条蛋白序列氨基酸数为72~116、理论等电点为9.94~11.59、分子质量为7 408.70~12 465.55、脂肪系数为85.94~114.12,除K7KNK4没有跨膜区外,其余13条Nodulin蛋白均有1~2跨膜区。二级结构主要由α螺旋和无规则卷曲组成,13个模体中模体1、模体2、模体3和模体4保守性强,系统发育进化树由6个分枝组成,分枝Ⅵ的A0A0B2P3C8、I1MWA0三维结构预测结果也相似。  相似文献   

20.
Rice milling is one of the important factors that determines the physicochemical properties of rice flour. Dry milling is a simple and quick process, though it produces high levels of damaged starch that is not desirable in some application. Since fermentation can change the structure of starch as well as its physicochemical properties, the effect of fermentation on dry-milled rice flour was evaluated with the aim of improving flour quality for use as food ingredient in food industry. After fermentation at 37 °C for 24 h by Lactobacillus amylovorus, the dry-milled rice flour showed similar proximate compositions, physicochemical properties, and surface structures as semi-wet-milled rice products. Thus, the results suggest that it can be applied to produce desirable food materials for preparation of rice-based products.  相似文献   

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