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1.
李岩  张杰 《材料导报》2015,29(17):1-5
三维结构纳米纤维构件具有内部比表面积大、孔径大、孔互联互通、组成和结构可控、整体材料结构具有一定支撑性的优点,因此具有广阔的应用前景,特别是在组织支架方面的应用成为人们关注的焦点。静电纺丝制备的纳米纤维由于具有直径超细、表面积大、多孔、高孔隙率、与骨架细胞外基质的结构极为相似等特点,迅速发展成为一种前景非常广阔的组织工程支架材料,同时通过一定的方法可以得到三维结构的静电纺丝纳米纤维组织支架。综述了国内外通过静电纺丝工艺来制备三维结构纳米纤维组织支架的方法,包括连续不间断纺丝法、多层交替纺丝法、纺丝设备改进法、后处理法、辅助收集法、添加致孔剂法、自组装法等。  相似文献   

2.
简述了组织工程支架的重要性及要求,综述了制备组织工程支架所用生物活性陶瓷、天然高分子及合成高分子材料的特点,着重介绍了静电纺丝法、热致相分离法、溶剂浇铸/粒子沥滤法和冷冻-干燥法制备组织工程支架的原理,提出了组织工程支架研究存在的问题,并展望了组织工程支架未来的研究方向。  相似文献   

3.
同轴射流技术制备纳米复合材料研究进展   总被引:11,自引:2,他引:9       下载免费PDF全文
简要介绍了基于电流体动力学射流技术的静电纺丝和静电喷涂的基本原理和发展过程,重点讨论了两种同轴射流技术——同轴静电纺丝和同轴静电喷涂技术的研究现状,包括纳/微米包囊、壳-芯结构的纳米纤维和中空纳米纤维或纳米管的制备。介绍了该技术在药物释放体系、组织工程支架、载药医用敷料和缝合线等方面的潜在应用前景,并对其未来发展进行了展望。  相似文献   

4.
殷丽华  牟星  余占海  王琳 《材料导报》2013,27(17):110-112,120
简要介绍了丝素蛋白的特性以及丝素蛋白复合支架在医学组织工程中的应用,综述了丝素蛋白及其复合支架制备方法的研究进展,主要包括冷冻干燥法、静电纺丝法、气体发泡法、致孔剂制孔法、快速成型法等,同时还比较了各种制备方法的优缺点。  相似文献   

5.
李燕  杨德智 《硅谷》2013,(15):5-6,12
静电纺丝作为一种纳米纤维支架的仿生构建方法 ,已在软骨组织工程领域中得到越来越多的应用和关注。但是,由于静电纺纳米纤维支架的孔径过小以及无法精确控制支架的形状影响其向临床应用转化。近年来涌现出许多控制纳米纤维支架结构的方法。本文对控制纳米纤维支架结构的方法进行了综述,并对纳米纤维支架在软骨组织工程中应用的主要挑战和前景,提出了看法。  相似文献   

6.
静电纺丝制备小直径血管支架   总被引:1,自引:0,他引:1  
向萍  李敏 《材料导报》2011,(3):132-135
静电纺丝技术是一种简便易行的新型小直径血管支架制备方法,能够形成与天然血管细胞外基质类似的纳米级三维结构———仿生天然血管细胞外基质,促进细胞黏附和增殖。介绍了静电纺丝技术制备小直径血管支架的原理以及对采用不同材料(生物高分子材料、可降解人工合成材料及复合材料)静电纺丝制备的小直径血管支架的理化性能和生物学特征进行了描述与比较,指出了静电纺丝技术制备小直径血管支架研究的热点与不足。  相似文献   

7.
组织工程的主要目的是利用高分子生物材料构建类似细胞外基质的三维支架,用于诱导细胞粘附、生长、迁移和分化,从而修复受损组织或器官。超临界二氧化碳(SC-CO2)辅助工艺制备三维组织工程支架能克服传统制备工艺中支架有机溶剂残留量高的问题,在组织工程领域具有广阔的应用前景。综述了国内外SC-CO2辅助技术,如SC-CO2辅助发泡、SC-CO2辅助相分离、SC-CO2辅助干燥、SC-CO2辅助静电纺丝等在三维组织工程支架制备方面的研究进展及存在的问题。  相似文献   

8.
电纺丝制备纳米纤维及其应用   总被引:1,自引:0,他引:1  
电纺丝技术是利用高压静电将聚合物或具有粘弹性的溶液制备成纳米级直径纤维的一种加工技术。电纺丝纤维膜由于其高比表面积、良好的生物仿生性能,在生物组织工程支架、药物载释、伤口修复等方面有较高的应用价值。近年来,大量文献报道,通过对电纺丝装置以及纺丝过程参数的改进和优化,制备出功能化和具有特殊结构的纳米纤维材料。本文从电纺丝装置的改进、纺丝过程优化等方面简述了电纺丝技术的进展。概述了电纺丝法制备特殊结构的纳米纤维的方法,及其在生物组织工程、药物载释等方面的应用。  相似文献   

9.
作为一种天然的纤维蛋白,蚕丝具有良好的力学性能、生物相容性和可降解性,这使其在生物医学方面的应用不断拓展。多孔支架能够为细胞的粘附和增殖提供有利的微环境,在重塑和修复组织的过程中起着至关重要的作用。本文综述了丝素蛋白支架的多种制备方法,如静电纺丝法、冷冻干燥法、沥除法和发泡法等,阐述了丝素蛋白支架的表面改性方法,总结了丝素蛋白支架在组织工程中的应用。  相似文献   

10.
静电纺丝法制备功能性改性聚乳酸纳米纤维,可以实现其尺寸、形貌及组成的可调可控,主要应用于生物医学、骨组织支架工程以及食品包装等领域。详细述评了静电纺丝法制备聚乳酸与无机物、天然高分子、有机物及导电高分子的复合或共混纤维材料的制备工艺、性能研究和应用前景方面的最新进展。经改性的聚乳酸静电纺丝功能性纤维能够克服了聚乳酸纤维亲水性不够、粘附性较弱、脆性较大等不足,赋予其抗菌性、导电性或更好的力学性能等。  相似文献   

11.
Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.  相似文献   

12.
In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.  相似文献   

13.
Quality Study of Honeycomb Core Shaping Without Wax Stabilization   总被引:1,自引:0,他引:1  
Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.  相似文献   

14.
Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.  相似文献   

15.
In continuous hot-dip galvanization process the corrosion and chemical stability of the sink roll in the galvanizing bath are important problem which effects on the quality and productivity. In order to protect the sink roll the carbide cermet and/or ceramic coatings were deposited on the surface of the sink roll. The WC-, Cr3 C2-cermet coatings were deposited by high velocity oxygen fuel (HVOF) spray, respectively. The coating samples were immersed in molten Zn-alloy containing 50 wt % aluminum at 833 K for 24 hr and 144 hr, respectively. The inter-diffusion and inter-reaction of Zn, Al and elements in coating and corrosion behaviors of these coatings were investigated by XRD, SEM and EPMA etc. The corrosion mechanisms of the carbide cermet coatings and ceramic coatings in molten High Al-Zn-alloy were approached.  相似文献   

16.
In many situations, ice often adheres to a cooling solid surface, frequently causing serious accidents. It is critical to clarify the mechanism of ice adhesion to the cooling surface in order to prevent ice adhesion. In a past study, the shearing stresses of two kinds of test plates with a copper surface having the higher thermal conductivity were measured. The shearing stress corresponds to ice adhesion force. Both shearing stresses were significantly different; however, the cause remains unclear.Therefore, the present study focuses on an oxide layer as the main factor causing the difference of both shearing stresses; the influence of the oxide layer formed on shearing stress was discussed. And in the removal and reformation processes of the oxide layer, the time variation of the shearing stress was clarified. Moreover, the relationship between the state of the copper surface and the shearing stress was also clarified by surface analysis.  相似文献   

17.
正When you are enjoying the green,energy-saving and healthy lighting of IKEA LED luminaire,you may not realize that most of IKEA’s LED bulbs are produced by the LED luminaire smart manufacturing system of Hangzhou Zhongwei Photoelectricity CO.,LTD(ZVISION).No longer enclosed in the laboratory,the product standards are brought into the factory workshop and even to the entire production process.Thus,the standards are promoted and applied in a favorable way by enterprises,benefitting consumers with high quality products.  相似文献   

18.
正The international standard,ISO 8124-6,Safety of toys–Part 6:Certain phthalate esters in toys and children’s products,was officially issued by ISO worldwide on August 15.It was the first time for Chinese experts to lead the ISO standard development in toys industry.The standard was drafted by a group of Chinese experts from SAC/TC for toys and relevant Chinese departments and finally completed by a dedicated international group of experts.ISO 8124-6 makes a substantive breakthrough in the aspects of the scope of toys,limitation of plasticizer types,control of test cost,accuracy of test,operation convenience,etc.,offering the operational guidance for toy manufactures and testing laboratories.  相似文献   

19.
正Themed on"quality,innovation,development",the first China Quality Conference(Beijing)was held in the Great Hall of the People on September 15.Chinese Premier Li Keqiang delivered an important speech at the conference.State Councilor Yang Jing and Wang Yong attended the conference with over 600 domestic and international representatives from foreign,regional and international quality organizations  相似文献   

20.
正The National Working Meeting on Land and Resources Standardization was held in Beijing on July 15,2014.Wang Min,the Deputy-Minister of the Ministry of Land and Resources,and Yin Minghan,the Chief-Engineer of SAC addressed the meeting.Representatives from relevant competent departments and technical committees were present.The meeting aims to summarize work,discuss existing problems and make clear working thoughts,promoting standardization work of land and resources to a new level.Wang Min pointed out that the standardization work of land and resources should be centered on the basic principles of"protecting land and resources dutifully,intensively and economically utilizing land and resources,and making all-out efforts to safeguard the public’s rights and interests",highlighted the  相似文献   

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