共查询到18条相似文献,搜索用时 93 毫秒
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根据大腹园蛛牵引丝力学性能的结构机理及其聚集态结构和形态结构特征,初步建立了以皮芯层结构为基础的蜘蛛丝拉伸力学模型,分析了皮芯层比例及结构对蜘蛛丝纤维力学性能的影响。以层状复合材料的拉伸变形为依据,分析了蜘蛛丝纤维的拉伸断裂过程与皮芯层性能间的关系。 相似文献
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蜘蛛丝纤维的来源与组成、性能,在医疗、军事、纺织制衣的应用,综述了国内外利用生物技术和基因工程对蜘蛛丝的研究进展。 相似文献
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蜘蛛丝应力—应变行为的分子结构机理 总被引:2,自引:0,他引:2
利用激光拉曼光谱技术研究了大腹园蛛牵引丝、蛛网框丝和内层包卵丝的分子构象,分析了蜘蛛丝的分子构象差异对其应力-应变行为的影响,探索了蜘蛛丝优异力学性能的分子结构机理。 相似文献
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蜘蛛牵引丝是由蜘蛛主壶腹腺产生的一种具有高度重复结构的蛋白质纤维,它将高抗张强度和高弹性奇妙地结合于一体,是自然界强度最高的纤维.基因解析揭示出牵引丝至少存在两种高度重复的蛋白组分,每种蛋白的重复单元都显示出富丙氨酸区和富甘氨酸区交替的模块结构特征.采用分子工程技术不仅可以生产出具有天然牵引丝蛋白特性的重组蜘蛛丝蛋白,也可为研究牵引丝蛋白的模块结构与功能特性之间的关系开辟道路.文中结合我们的研究综述了牵引丝蛋白的模块结构及其分子工程的研究进展,并就其未来发展进行展望. 相似文献
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蜘蛛牵引丝是由蜘蛛主壶腹腺产生的一种具有高度重复结构的蛋白质纤维,它将高抗张强度和高弹性奇妙地结合于一体,是自然界强度最高的纤维.基因解析揭示出牵引丝至少存在两种高度重复的蛋白组分,每种蛋白的重复单元都显示出富丙氨酸区和富甘氨酸区交替的模块结构特征. 采用分子工程技术不仅可以生产出具有天然牵引丝蛋白特性的重组蜘蛛丝蛋白,也可为研究牵引丝蛋白的模块结构与功能特性之间的关系开辟道路. 文中结合我们的研究综述了牵引丝蛋白的模块结构及其分子工程的研究进展,并就其未来发展进行展望. 相似文献
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蜘蛛丝属线状蛋白质,具有独特的结构和性能特点,是世界上拉力强度和弹性最强的纤维之一,其强度比钢还要硬.一些蜘蛛丝蛋白的基因已被克隆出来,并且用不同的表达载体表达,同时进行了成丝研究.由于蜘蛛丝性能独特,在许多领域具有良好的应用前景. 相似文献
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成丝的速度与方式和蜘蛛丝力学性能的关系 总被引:1,自引:0,他引:1
为了分析蜘蛛丝的力学性能和成丝条件间的关系,研究了不同速度下人工卷取的蜘蛛牵引丝以及蜘蛛垂直下落时分泌的牵引丝的力学性能.研究结果表明,随着卷取速度的增大,蜘蛛丝的断裂强度有一极大值,在高速卷取时强度的变化较低速时平缓.垂直下落时蜘蛛分泌的牵引丝的综合力学性能优异,但断裂强度不一定大于人工卷取的丝.成丝速度和成丝方式都对蜘蛛丝的性能有很大影响. 相似文献
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蜘蛛丝的结晶结构及其取向 总被引:8,自引:0,他引:8
研究和分析了大腹园蛛的牵引丝、内层包卵丝的结晶结构及其取向,探索了大腹园蛛丝纤维分子链的排列状态、结晶结构和蜘蛛丝力学性能间的关系。 相似文献
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Spider dragline silk, which is produced in spider major ampullate gland, is a composite proteinacious fiber with highly repetitive Ala-Gly-rich domain. The unique combination of both high tensile strength and high elasticity makes spider dragline silk superior to almost any other natural or synthetic fibers. Cloning of the genes reveals that the silk is composed of at least two major proteins. Each protein component contains multiple repeats of modular structures that alternate between Ala-rich domains and Gly-rich domains. Molecular engineering not only opens a door to the production of spidroins but also provides a valuable experimental system to test and further establish the relationship between modular structures and mechanical properties. Here, based on our own studies, we review the latest progress of the modular structure and genetic engineering and outline the future prospects. 相似文献
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The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spiders active control during spinning process. To investigate the relationship between the morphology of dragline silk fibers and spinning conditions, four samples were made at the reeling rates of 1mm/s, 20mm/s, 43.5mm/s and 110mm/s from the major ampullate glands of Araneus Ventricosus and the other two of dragline silks were prepared from a crawling or dropping spider. The surface microstructure and nanofibril characteristic were analyzed with atomic force microscopy (AFM). AFM images of 2000nm*2000nm and 500nm*500nm of these samples showed that the spinning condition influenced the surface roughness and fibril size, while AFM images of 200nm*200nm clearly displayed that dragline silk of Araneus Ventricosus included sheet macro-conformation structure. These results can facilitate the further investigation of the spinning mechanism of a spider in order to understand mechanical properties and macromolecular structures of dragline silk. 相似文献
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Surprising strength of silkworm silk 总被引:1,自引:0,他引:1
Commercial silkworm silk is presumed to be much weaker and less extensible than spider dragline silk, which has been hailed as a 'super-fibre'. But we show here that the mechanical properties of silkworm silks can approach those of spider dragline silk when reeled under controlled conditions. We suggest that silkworms might be able to produce threads that compare well with spider silk by changing their spinning habits, rather than by having their silk genes altered. 相似文献
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Unrestrained spider dragline 'super-contracts' when it is wetted, causing its length to shrink by about half and its diameter to almost double. Here we measure the supercontraction stresses generated upon initial exposure of spider dragline to moisture and find that they are transient, as well as being greater than previously estimated. Our findings cast doubt on suggestions that supercontraction may help to maintain tension in wet webs and could limit the potential load-bearing applications of silk and its analogues. 相似文献
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Solid-state NMR determination of the secondary structure of Samia cynthia ricini silk 总被引:1,自引:0,他引:1
Silks are fibrous proteins that form heterogeneous, semi-crystalline solids. Silk proteins have a variety of physical properties reflecting their range of functions. Spider dragline silk, for example, has high tensile strength and elasticity, whereas other silks are better suited to making housing, egg sacs or the capture spiral of spiders' webs. The differing physical properties arise from variation in the protein's primary and secondary structure, and their packing in the solid phase. The high mechanical performance of spider dragline silk, for example, is probably due to a beta-sheet conformation of poly-alanine domains, embedded as small crystallites within the fibre. Only limited structural information can be obtained from diffraction of silks, so further characterization requires spectroscopic studies such as NMR. However, the classical approach to NMR structure determination fails because the high molecular weight, repetitive primary structure and structural heterogeneity of solid silk means that signals from individual amino-acid residues cannot be resolved. Here we adapt a recently developed solid-state NMR technique to determine torsion angle pairs (phi, psi) in the protein backbone, and we study the distribution of conformations in silk from the Eri silkworm, Samia cynthia ricini. Although the most probable conformation in native fibres is an anti-parallel beta-sheet, film produced from liquid directly extracted from the silk glands appears to be primarily alpha-helical. 相似文献
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Molecular Fundaments of Mechanical Properties of Spider Silk 总被引:1,自引:0,他引:1
Dragline, framework and cocoon silk fibers of Araneus Ventricosus were used for this study. To investigate the microstructure mechanisms of stress-strain behavior of spider silk, firstly, amino acid compositions were analyzed and molecular conformations and crystallinity were measured with Raman spectra and X-ray diffraction respectively. The results showed that there were more amino acids with large side groups and polar ones in spider silk than those of Bombyx silk, and the amino acid distribution varied with different spider silk. The molecular structures were mainlyα-helix and β-sheet, and random coil andβ-turn existed as well. The proportions and arrangement of these conformations of dragline silk were different from framework and cocoon silk fibers. Microstructure was one of important factors of excellent mechanical properties of spider silk. Crystallinity of spider silk was very low, which implied that the roles of crystal on spider silk were not as great as other protein fibers. 相似文献