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The pedicel, nest paper, and larval silk ofPolistes annularis nests were analyzed by high-resolution solid-state [13C]NMR. The pedicel was found to have a high nitrogen content (11%), and the NMR spectra indicated that it is a mixture of carbohydrate and protein. The pedicel protein has an amino acid composition that is very rich in glycine, alanine, serine, and proline (67% of identified residues), similar to that of some insect silks. Solid-state [13C]NMR indicated that the nest paper is composed predominantly of cellulose. Silk, spun by matureP. annularis larvae, was shown by [13C] NMR and amino acid analysis to be a protein very high in serine and alanine (53%), but the amino acid composition is distinct from that of the pedicel protein. 相似文献
13.
贾艳梅 《天津工业大学学报》2010,29(5)
以柞蚕落绵为原料制备丝肽,并对其进行红外及紫外光谱分析.采用该丝肽整理棉织物,然后用艾蒿、苏木、红茶3种天然染料对整理前后的棉织物进行染色,探讨丝肽整理对棉织物天然染料染色性能的影响.结果表明:经丝肽整理后,棉织物采用3种天然染料染色的K/S值均有不同程度的提高,摩擦牢度和皂洗牢度略有下降,其中红茶Cu2+媒染样品的K/S值提高最显著,为整理前的2.24倍,其皂洗和摩擦牢度均达到3级以上.棉织物经丝肽整理后,断裂强力稍有下降,白度基本保持不变,柔软度有所改善. 相似文献
14.
为了解混纺比对天然彩色棉/绢丝混纺织物风格的影响,制备了系列天然彩色棉(棕)/绢丝混纺机织物,并采用FAST对混纺织物的风格进行测试与分析.研究表明,随着绢丝含量的增加,天然彩色棉/绢丝混纺织物的强伸性能得到明显改善,织物的风格变得相对滑爽,柔软,但造型性有所变差.少量绢丝的加入(<10%)对织物柔软性的改善明显. 相似文献
15.
To obtain water-insoluble silk fibroin(SF) materials, polyethylene glycol diglycidyl ether(PEG-DE) was selected as a crosslinking agent to prepare SF films(blends). The reaction conditions were optimized for the crosslinking of the SF molecules. The hot water stability of the blends was measured using BCA protein assay and gravimetric analysis. The molecular conformation and crystalline structure of the blends were analyzed by FTIR and XRD, respectively. When the mass ratio of SF:PEG-DE was 1.0:0.8, the hot water loss rate of the SF blends was minimized. PEG-DE could induce SF molecules to form β-sheets during the gel reaction process, resulting in improved crystallinity and hot water dissolved resistance of the blend films. In order to demonstrate the cytotoxicity of the chemical reagents used to crosslink SF, L929 cells were seeded on the blend film(SF:PEG-DE = 1:1) and cultured for 3 days. Cells of L929 readily adhered and spread in the fusiform on the blend film resulting in high cell viability. The extracted liquid from the SF porous film did not inhibit cell proliferation, as estimated by the MTT assay. 相似文献
16.
In this study, biomimetic sodium alginate (SA)/silk fibroin (SF) scaffolds were successfully fabricated by supercritical CO2 technology. The SA/SF scaffolds exhibited an interconnected porous and extracellular matrix (ECM)-like nanofibrous structures. Moreover, the SA microparticles were embedded in the SF scaffolds. Increasing the content of SA microparticles could improve tensile strength and compressive strength of the SF scaffolds and reduce the porosity of the SF scaffolds. The addition of the SA microparticles could also regulate the degradation rate of the SA/SF scaffolds. Furthermore, the results of in vitro biocompatibility evaluation, indicated that the SA/SF scaffolds exhibited no obvious cytotoxicity and higher cell adhesion ability and were more favorable for L929 fibroblasts proliferation than pure SF scaffolds. Therefore, the SA/SF scaffolds with ECM-like nanofibrous and interconnected porous structure have potential application in skin tissue engineering. 相似文献
17.
Leitao Cao Chao Ye Hao Zhang Shuo Yang Yicheng Shan Zhuochen Lv Jing Ren Shengjie Ling 《Advanced functional materials》2023,33(27):2301404
Ionotronic artificial motion and tactile receptor (i-AMTR) is essential to realize an interactive human-machine interface. However, an i-AMTR that effectively mimics the composition, structure, mechanics, and multi-functionality of human skin, called humanoid i-AMTR, is yet to be developed. To bridge this technological gap, this study proposes a strategy that combines molecular structure design and function integration to construct a humanoid i-AMTR. Herein, a silk fibroin ionoelastomer (SFIE) with double cross-linked molecular structure is designed to mimic the composition and structure of human skin, thereby resolving the conflict of stretchability, softness, and resilience, suffered by many previously reported ionotronics. Functionally, electromechanical sensing and triboelectricity-based tactile perception are integrated into SFIE, to enable simultaneous perception of both motion and tactile inputs. By further leveraging the machine learning and Internet of Things (IoT) techniques, the proposed SFIE-based humanoid i-AMTR precisely senses the movement of human body and accurately sortball objects made of different materials. Notably, the success rate for 610 sorting tests reaches as high as 92.3%. These promising results essentially demonstrate a massive potential of humanoid i-AMTR in the fields of sorting robots, rehabilitation medicine, and augmented reality. 相似文献
18.
Zhihai Fan Hongxiang Liu Zhaozhao Ding Liying Xiao Qiang Lu David L Kaplan 《Advanced functional materials》2023,33(33):2301839
Different tissues have complex anisotropic structures to support biological functions. Mimicking these complex structures in vitro remains a challenge in biomaterials designs. Here, inspired by different types of silk nanofibers, a composite materials strategy is pursued toward this challenge. A combination of fabrication methods is utilized to achieve separate control of amorphous and beta-sheet rich silk nanofibers in the same solution. Aqueous solutions containing two types of silk nanofibers are simultaneously treated with an electric field and with ethylene glycol diglycidyl ether (EGDE). Under these conditions, the beta-sheet rich silk nanofibers in the mixture responded to the electric field while the amorphous nanofibers are active in the crosslinking process with the EGDE. As a result, cryogels with anisotropic structures are prepared, including mimics for cortical- and cancellous-like bone biomaterials as a complex osteoinductive niche. In vitro studies revealed that mechanical cues of the cryogels induced osteodifferentiation of stem cells while the anisotropy inside the cryogels influenced immune reactions of macrophages. These bioactive cryogels also stimulated improved bone regeneration in vivo through modulation of inflammation, angiogenesis and osteogenesis responses, suggesting an effective strategy to develop bioactive matrices with complex anisotropic structures beneficial to tissue regeneration. 相似文献
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本文论述了改革开放以来中国茧丝绸行业取得的发展,同时指出了当前茧丝绸行业面临的日益突出问题和当前茧丝绸行业经济运行的特点,在此基础上,相应提出了四条主要建议。 相似文献