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1.
阐述类金刚石膜的结构、性能、形成机制,特别讨论了等离子体技术制备类金刚石膜的各种方法,以及类金钢石膜在印刷机制造和产品包装领域的应用前景,还结合相关的类金刚石膜制备研究与性能测量,就在印刷包装方面的实际应用提出了进一步需要解决的问题.  相似文献   

2.
类金刚石薄膜和金刚石薄膜的最新制备技术与各种特性   总被引:4,自引:0,他引:4  
类金刚石薄膜等硬质碳膜具有许多优异特性,其开发研究已引起人们的极大关注。文章就类金刚石薄膜和金刚石薄膜的最新制备方法与各种特性进行了解说。  相似文献   

3.
金刚石膜的出现突破了传统人造金刚石尺寸的限制,使得金刚石的电学、热学、光学和电子学等方面的优异性能得到了利用,极有可能为超硬材料行业开拓新的更大的市场。金刚石膜或类金刚石膜用来作为场发射的阴极,是其极具前景的应用之一。文章叙述了冷阴极场发射的概念、金刚石膜的性能和用作冷阴极场发射显示器的相关研究,介绍了国内外相关研究的成果和发展前景,供同行参考。  相似文献   

4.
新开发类金刚石(DLC)砂轮所用的DLC纤维是涂敷DLC膜的铝板经压延机单向压延而成的,DLC膜断裂成纤维状,而且纤维的方向保持一致,经几层叠合,由结合剂固结并烧结制成DLC纤维砂瓦,用其制作出杯形砂轮。然后,利用这种砂轮进行硅片、石英、SKD-11淬硬钢的磨削。硅片的磨削结果表明,加工表面粗糙度可达Ry=15nm(Ra=2nm)。  相似文献   

5.
化学传感器特别是光化学传感器已经被广泛研究,并应用于检测目标物如食品中的重金属。静电纺丝纳米纤维膜由于具有高比表面积、高孔隙率、可控性良好和易功能化等特点,可以被用来固定传感器以提高其灵敏度。本文主要综述静电纺丝纳米纤维膜基光化学传感器的制备及其在重金属离子检测中的应用进展。首先,简单介绍光化学传感器及静电纺丝纳米纤维膜基光化学传感器,随后根据其制备方法的差异分为高分子聚合物化学修饰法、高分子聚合物物理共混法、纳米纤维化学修饰方法和纳米纤维物理吸附方法4类,并分别综述其制备得到的静电纺丝纳米纤维膜基光化学传感器应用于重金属检测的进展,这4类方法各有优势,都具有较好的应用前景。本文将为静电纺丝纳米纤维膜基光化学传感器用于目标物的检测提供指导。  相似文献   

6.
介绍了提高中空纤维膜力学性能的方法,即通过增强体增强法制备兼具增强体力学性能优异和分离层分离精度高特点于一体的增强型中空纤维膜,解决传统单质中空纤维力学性能与分离性能 不能兼顾的矛盾。分析了增强型中空纤维膜的及其制备方法,包括连续纤维增强型中空纤维膜、编织管增强型中空纤维膜和多孔基膜增强型中空纤维膜,阐述了3种增强型中空纤维膜的制备技术路线和致孔机制,回顾了其研究进展,并展望了增强型中空纤维膜的发展及应用前景。  相似文献   

7.
直流喷射化学气相沉积金刚石膜,其完整性一直是个难以解决的技术难题,并且直接影响了其推广应用。文章通过研究金刚石膜的质量、衬鹿与膜的结合力、以及衬鹿的膨胀系数等,分析了影响金刚石膜完整性的几个关键因素。  相似文献   

8.
简要描述了CVD金刚石薄膜技术的发展历程。介绍了纳米特别是超纳米金刚石膜、CVD金刚石大单晶的技术特点及其应用。超纳米金刚石膜在MEMS(微机电系统)、电化学和生物医学上的应用和CVD金刚石大单晶是当前的研究热点。简言之,金刚石的发展向着更大或者更小的方向深入进行,即"非大即小"。  相似文献   

9.
采用直流热阴级化学气相沉积(DC-PACVD)方法,以NH3+CH4+H2混合气体作为气源,通过改变氨气浓度,在单晶硅(111)基片上沉积纳米金刚石膜.采用扫描电子显微镜、原子力显微镜和拉曼光谱仪分析了不同氨气浓度下制备的纳米金刚石膜。结果表明:在基体温度为700℃条件下,随着氨气浓度的增大,纳米金刚石膜中的金刚石相含量增加,非金刚石相含量相对减少;晶粒的平均粒度减小。在一定范围内氨气浓度增加,有助于提高纳米金刚石膜质量;在氨气流量达到8 mL/min时,获得了质量最好的纳米金刚石膜,其平均晶粒尺寸约为64 nm、均方根粗糙度约为27.4 nm。并提出了掺氮纳米金刚石薄膜的生长模型,对相应现象给出了解释。  相似文献   

10.
文章对CVD金刚石的物理特性进行了描述,研究了CVD金刚石膜制作超精密刀具的工艺技术方法,设计了生产工艺流程,对生产的CVD金刚石膜直刃和圆弧超精密刀具的精度及加工件的精度进行了测试,表明CVD金刚石膜是一种非常优异的超精密刀具的制作材料,应用前号非常广阔。  相似文献   

11.
为了研究类金刚石膜的结构,采用射频等离子化学气相沉积的方法制备出类金刚石薄膜,傅立叶红外透射光谱对沉积薄膜进行结构成分分析。结果表明,采用射频等离子体化学气相沉积方法,可以在很短时间内于PET瓶内沉积一定纳米厚度的DLC膜,但受到电极的影响较大。选用不同大小的电极,所制备的DLC的结构不同,薄膜中sp2和sp3比例和放电功率有较大的关系。同时发现薄膜的成分受乙炔在氩气中的比例影响,提高功率是减少沉积时间的主要手段。  相似文献   

12.
Amanda B. Dias 《LWT》2011,44(2):535-1021
Rice flour is a low-cost starchy material, produced from rice that is broken during processing. Rice flour-based films have promising application on food packaging, because of their environmental appeal and low cost. Nevertheless, their mechanical and moisture barrier properties should be improved. The aim of this study was to develop biodegradable films based on rice flour and enhance their properties by reinforcing them with cellulose fibers. In this way, rice flour films with and without fibers were prepared by casting, with glycerol or sorbitol as plasticizer. Their physicochemical, microscopic and mechanical properties were studied. SEM analysis of films revealed compact structures. Films prepared with fibers presented lower water vapor permeabilities if compared with films without fibers. Films containing sorbitol were less permeable to water and more rigid. The incorporation of fibers reinforced mechanically the flour-based films, which presented higher tensile strength, but did not influence their deformation capacity. Therefore, preparing biodegradable films from rice flour is a new alternative of using this raw material. The use of cellulose fibers as reinforcing agent is a viable alternative to improve the properties of rice flour-based films, because they are biodegradable and available at low cost.  相似文献   

13.
羊毛溶解可行性及其溶液的制取   总被引:4,自引:4,他引:0  
文章介绍了羊毛角朊的溶解性质及其理想溶解方法.通过分析溶剂的选择,详细描述了羊毛角朊溶解助剂、工艺过程及制备步骤.对溶解液进行了粘度测量,并采用傅立叶变换红外光谱(FTIR)技术对羊毛和角朊溶液膜作了对比测试和分析.实验得出,羊毛溶解后得到的角朊膜在分子结构上变化不大,但其无序结构明显,大分子构象形式发生了变化.  相似文献   

14.
针对天然纤维基材上磁控溅射纳米膜易整层脱落问题,系统测试了不同纤维基材上磁控溅射结构生色膜的耐摩擦色牢度和耐皂洗色牢度,研究了样品的初始含水率和低温等离子体表面改性对磁控溅射膜与纤维基材结合牢度的影响,进而借助扫描电子显微镜并结合纤维材料的理化性能分析得出磁控溅射膜与各种纺织基材结合牢度不同的原因。结果表明:热塑性的涤纶存在软化点,磁控溅射高能粒子沉积到纤维表面时动能转化为热能,使涤纶局部达到软化点,粘结溅射粒子;棉和蚕丝没有软化点,纤维对磁控溅射粒子无熔融粘结作用,且棉和蚕丝具有高吸湿溶胀性,皂洗过程中水分子的侵入削弱纤维和纳米粒子间的作用力,致使磁控溅射膜易脱落。  相似文献   

15.
Cellulose fibers were miniaturized by microfluidics technology to decrease their size and incorporated in hydroxypropyl methylcellulose (HPMC) films to study the effect of addition of such fibers on the mechanical and barrier properties of HPMC films suitable for application in food packaging. The particle size of fibers and the mechanical properties, water vapor and oxygen permeabilities, total pore volume, and light and electron microscopy micrographs of films were analyzed. Incorporation of cellulose fibers in the films improved their mechanical and barrier properties significantly. This study is the first to investigate the use of microfluidics technology for the purpose of decreasing the size of cellulose fibers and the addition of reduced size microfibers to improve physical properties of HPMC films.  相似文献   

16.
In this work we have explored capillary adhesion between hair fibers treated with different types of oils. With coconut, olive, and sunflower oils the capillary adhesion was found to decrease with time, but not with mineral oil. Application of heat reduced the capillary adhesion further for coconut and sunflower oils. Again, this was not observed with mineral oil. Based on an earlier study, where coconut oil was found to penetrate hair while mineral oil was unable to do so, it was hypothesized that the reduction in capillary adhesion resulted from the penetration of oil into the fiber, leaving a thinner oil film on the surface. Such a reduction in capillary adhesion can be explained by changes in Laplace pressure and in the areas of liquid bridges formed between the fibers. The thinning of oil films on the surface of hair has been confirmed independently by goniophotometric measurements on single hair fibers treated with coconut, sunflower, and mineral oils. Thick films of oil (thicker than approximately 0.5 μm) are known to mask the scale structure. As the oil is absorbed into the hair, the film thins with time and application of heat, and the scale structure reappears. This change can be conveniently determined by measuring the scale angle, using the well-established goniophotometric protocol. The agreement between the two methods supports the concept that the reduction in capillary adhesion between hair fibers is most likely because of thinning of oil films by absorption of oil into the hair.  相似文献   

17.
Perspectives for chitosan based antimicrobial films in food applications   总被引:6,自引:0,他引:6  
Recently, increasing attention has been paid to develop and test films with antimicrobial properties in order to improve food safety and shelf life. Active biomolecules such as chitosan and its derivatives have a significant role in food application area in view of recent outbreaks of contaminations associated with food products as well as growing concerns regarding the negative environmental impact of packaging materials currently in use. Chitosan has a great potential for a wide range of applications due to its biodegradability, biocompatibility, antimicrobial activity, non-toxicity and versatile chemical and physical properties. Thus, chitosan based films have proven to be very effective in food preservation. The presence of amino group in C2 position of chitosan provides major functionality towards biotechnological needs, particularly, in food applications. Chitosan based polymeric materials can be formed into fibers, films, gels, sponges, beads or even nanoparticles. Chitosan films have shown potential to be used as a packaging material for the quality preservation of a variety of food. Besides, chitosan has widely been used in antimicrobial films to provide edible protective coating, in dipping and spraying for the food products due to its antimicrobial properties. Chitosan has exhibited high antimicrobial activity against a wide variety of pathogenic and spoilage microorganisms, including fungi, and Gram-positive and Gram-negative bacteria. The present review aims to highlight various preparative methods and antimicrobial activity including the mechanism of the antimicrobial action of chitosan based films. The optimisation of the biocidic properties of these so called biocomposites films and role of biocatalysts in improvement of quality and shelf life of foods has been discussed.  相似文献   

18.
为明确鱼皮胶原纤维尺寸及其添加量对鱼皮胶原纤维-淀粉复合膜性能的影响,本研究利用醋酸预处理鱼皮(3、6、9、12 h)获得了不同尺寸的胶原纤维(CF3、CF6、CF9、CF12),考察了不同类型胶原纤维及其添加量对共混膜性能的影响。采用傅里叶红外光谱技术、差示扫描量热法及扫描电子显微镜对复合膜进行结构表征。结果表明:添加鱼皮胶原纤维后,复合膜的断裂伸长率和水蒸气透过系数均增加,溶解性降低;当CF3和CF6添加量分别为7.5%和10%时能增强复合膜的抗拉强度,而且以10% CF6制备的复合膜抗拉强度性能最好,添加CF9和CF12时,复合膜的抗拉强度呈降低现象。对添加10% CF6制备的复合膜和纯淀粉膜进行表征,发现胶原纤维与淀粉相容性良好,在成膜过程中,胶原纤维交错在淀粉膜中,两者之间形成了氢键,但复合膜的热稳定性下降。  相似文献   

19.
Starch-based films have promising application on food packaging, because of their environmental appeal, low cost, flexibility and transparency. Nevertheless, their mechanical and moisture barrier properties should be improved. The aim of this work was to enhance these properties by reinforcing the films with cellulose fibers. Besides, the influences of both the solubility coefficient of water in the films (β) and the diffusion coefficient of water vapor through the films (Dw) on the films' water vapor permeability (Kw) were investigated. Films were prepared by the so-called casting technique, from film-forming suspensions of cassava starch, cellulose fibers (1.2 mm long and 0.1 mm of diameter), glycerol and water. The influence of fibers addition on Kw was determined at three relative humidity gradient ranges, ΔRH (2–33%, 33–64% and 64–90%). Films reinforced with cellulose fibers showed higher tensile strength and lower deformation capacity, and presented lower Kw than films without fibers. Kw showed strong dependency of β and Dw, presenting values up to 2–3 times greater at ΔRH = 64–90% than at ΔRH = 33–64%, depending on the film formulation. Therefore, adding cellulose fibers to starch-based films is a viable alternative to improve their mechanical and water barrier properties. Besides, this work showed the importance of determining film's water vapor permeability simulating the real environmental conditions the film will be used.  相似文献   

20.
针对软体柔性抗冲击纺织品轻质与高防护间的矛盾,综述了抗冲击纤维薄膜新材料、纤维表面改性及结构设计等方面的研究进展。分析了新型纤维薄膜材料包括石墨烯纤维及碳纳米管纤维的理论强度、制备方法及宏观制备存在问题;阐述了剪切增稠剂、纳米无机材料对纤维表面的改性应用的方法及抗冲击效果;阐明了单层织物结构、叠层结构等的结构优势及劣势以及气凝胶复合结构、硬软仿生结构在抗冲击方面的应用前景。研究认为:在满足抗冲击性能的前提下,通过表面改性、织物结构、层间结构、硬软结构等组合设计,可使其抗冲击性与舒适性协同;高纯度石墨烯、碳纳米管纤维和薄膜的宏量化无缺陷制备将是未来抗冲击纺织品超轻量化需要突破的技术瓶颈。  相似文献   

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