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排序方式: 共有175条查询结果,搜索用时 15 毫秒
41.
42.
In this paper we report on flexible a-Si:H solar cells prepared on polyethylene naphthalate (PEN) substrates using p-type hydrogenated nanocrystalline silicon thin films (p-nc-Si:H) as the window layer. The p-nc-Si:H films were prepared at low temperature (150 °C) using trimethylboron (TMB) as a dopant gas. The influence of the silane concentration (SC) on the electrical and structural properties of ultra-thin p-nc-Si:H as well as the performance of solar cells on PEN was investigated. The results show that the crystalline fraction and conductivity of p-nc-Si:H thin films diminished, while the deposition rate and RMS roughness of films increased, when the SC increases from 0.53% to 0.8%. For the a-Si:H solar cells on PEN with the non-textured electrodes, the best efficiency of 6.3% was achieved with the p-nc-Si:H thin films deposited at SC = 0.67%. 相似文献
43.
Samir Hamrit Kamal Djessas Kahina Medjnoun Idris Bouchama Mohammad Alam Saeed 《Ceramics International》2021,47(16):22881-22888
RF-magnetron sputtering has been carried out at room temperature to deposit vanadium-doped zinc oxide (VZO) nanostructured thin films onto flexible PEN substrates. The sputtering targets of compacted VZO nanopowder have been prepared using a rapid and inexpensive Sol-Gel synthesis followed by a supercritical drying process. Structural and morphological study of VZO particles in the targets has been carried out via X-ray diffraction and Transmission Electron Microscopy (TEM). The nanostructured thin films have been characterized to analyze the structural, morphological, electrical and optical properties as a function of vanadium content from 0 to 4 at.%. Structural characterization of VZO thin films revealed that the deposited thin films have been grown preferentially along (002) and exhibit the hexagonal wurtzite structure. The cross-sectional and microstructural analysis performed by Scanning Electron Microscopy (SEM) confirms the columnar growth of nanostructures. The deposited thin films exhibit transparent behavior with transmission >70% in the visible region. It has been observed that nanostructured thin films with vanadium content of 2% have demonstrated the lowest resistivity (6.71 × 10?4 Ω cm) with Hall mobility of 10.62 cm2 V?1 s?1. The deposited vanadium doped nanostructured thin films would have potential applications in electronic and optoelectronic devices. 相似文献
44.
论证了塑料啤酒瓶的优点和市场发展潜力,重点介绍了国外塑料啤酒瓶的种类及塑料啤酒瓶材料和加工设备的开发动向,指出啤酒瓶是在待我国合成树脂和塑料行业开发的一个大市场。 相似文献
45.
《Journal of Adhesion Science and Technology》2013,27(1-3):55-78
This paper describes the properties of an ultraviolet (UV) curable laminating adhesive system that can be used with PEN, PET and UV-stabilized PET films. The adhesive system that contains (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO) as photoinitiator was optimally cured with a V-bulb fitted ultraviolet irradiator. The laminated structures built with this adhesive system and PEN, PET and UV-stabilized PET films showed a large manufacturing operating window, both in terms of adhesive layer thickness, initial peel strengths above 1500 N/m, V- and D-bulb UV sources and curing speeds from 5– 10 m/min. The 600-h dry heat aging tests indicated that the UV-stabilized PET films underwent less than approximately 1% decrease in light transmission and less than a 1% gain in color. The UV-stabilized PET film and its laminate showed particularly strong retention of optical properties under damp aging and QUV weathering, compared to PEN and non-UV-stabilized PET films. Finally, the peel strengths of the laminates were retained to greater than 1300 N/m for laminate structures of 50 μm film thickness, whereas structures made from thicker films retained approx. 40–60% (700–1100 N/m) of their initial peel strength. 相似文献
46.
从耐热性、阻隔性、力学性能、耐化学药品性、耐紫外线性能等方面系统介绍了聚萘二甲酸乙二酯(PEN)的优异性能。详细阐述了PEN在薄膜产品(磁带、录象带)、包装容器(啤酒瓶、饮料瓶)、纤维制品(耐热纺织品)及注塑部件(医疗器械、汽车部件、仪表部件)中的应用。并从原料、技术及市场三个方面说明了我国开发PEN的有利条件。 相似文献
47.
48.
The transesterification reaction of poly(ethylene terephthalate)/poly(ethylene 2,6‐naphthalate) blends during melt‐mixing was studied as a function of blending temperature, blending time, blend composition, processing equipment, and different grades of poly(ethylene terephthalate) and poly(ethylene 2,6‐naphthalate). Results show that the major factors controlling the reaction are the temperature and time of blending. Efficiency of mixing also plays an important role in transesterification. The reaction kinetics can be modeled using a second‐order direct ester–ester interchange reaction. The rate constant (k) was found to have a minimum value at an intermediate PEN content and the activation energy of the rate constant was calculated to be 140 kJ/mol. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2422–2436, 2001 相似文献
49.
21世纪的新型高分子材料——聚萘二甲酸乙二醇酯(PEN) 总被引:1,自引:0,他引:1
徐兆瑜 《化学推进剂与高分子材料》2002,(2):11-25
概述了近期开发的PEN的一般性质、合成方法,以及在高科技领域和包装行业等方面的应用情况和市场前景。 相似文献
50.
Dylan?Dae?Bong?Jung Allan?J.?EastealEmail author Debes?Bhattacharyya 《Materials Research Innovations》2003,7(5):269-274
Melt blends of poly (butylene terephthalate) (PBT) and poly (ethylene naphthalate) (PEN) with 30, 40, 50, 60 and 70 wt% PEN
were prepared using a single screw extruder and injection moulding machine. 13C and 1H nuclear magnetic resonance (NMR) spectra were obtained with a Bruker DRX-400 instrument, on solutions prepared by dissolving
samples of the homopolymers and each blend in deuterated trifluoroacetic acid + chloroform mixtures (1:1 by volume). The absence
of new signals in 1H and 13C spectra, that would be expected to result from transesterification reactions in the PBT + PEN blend system, provides convincing
evidence that such reactions do not occur in these blends under the melt processing conditions that were used. In the light
of published work on solid-state NMR studies of these and related blend systems, and our observations of partial miscibility
with a very small domain size, together with substantial enhancement of the mechanical properties of PBT by blending with
PEN, we conclude that the improvement in mechanical properties arises from molecular scale mixing of the homopolymers and
strong but non-covalent bonding interactions over the very large interfacial area between the PBT-rich and PEN-rich phases. 相似文献