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81.
An investigation was conducted on enhanced scratch resistance of polycarbonate (PC) substrates by low temperature plasma-polymerized organo-silicon oxynitride (SiOxCyNz) with various N2 flow rates. It was found that the low temperature plasma-polymerized SiOxCyNz with tetramethylsilane (TMS)-O2-N2 plasmas in room temperature (23 °C) can be used for improving the scratch resistance of PC substrates. Scratch test demonstrates this improvement. The scratch resistance of PC substrates was greatly enhanced from the overwhelming presence of scratching (90%) on un-treated PC substrates to a complete lack of scratching (0%) on TMS-O2-N2 plasma-polymerized PC substrates with steel wool for 200 cycles at 300 g loading. The results of this study indicate the performance of scratch resistance on PC substrates was highly dependent on the surface characteristics of PC substrates. The hardness of PC substrates was determined by the pencil test. The surface morphology of PC substrate was monitored by atomic force microscopy (AFM) and field emitted scanning electron microscopy (FESEM). The atomic compositions and chemical bondings of TMS-O2-N2 plasma-polymerized SiOxCyNz were analyzed by X-ray photoelectron spectroscopy (XPS). 相似文献
82.
A transition metal-free tandem process for the synthesis of 1,2,4-triazoloquinoxalines was described. The construction of this tricyclic system went through a one-pot condensation/nucleophilic aromatic substitution approach. This methodology applied to a broad range of substrates, which included 2-halogenated or 2-nitro aryl aldehydes and ketones. 相似文献
83.
Alexandre F. Bedernjak Paul W. Groundwater Mark Gray Arthur L. James Sylvain Orenga John D. Perry Rosaleen J. Anderson 《Tetrahedron》2013
The synthesis and microbiological evaluation of 7-, 8- and 9-nitro-1,2,4-trihalogenophenoxazin-3-one substrates with potential in the detection of nitroreductase-expressing pathogenic microorganisms are described. The 7- and 9-nitrotrihalogenophenoxazinone substrates were reduced by most Gram-negative microorganisms and were inhibitory to the growth of certain Gram-positive bacteria; however, the majority of Gram-positive strains that were not inhibited by these agents, along with the two yeast strains evaluated, did not reduce the substrates. These observations suggest there are differences in the active site structures and substrate requirements of the nitroreductase enzymes from different strains; such differences may be exploited in the future for differentiation between pathogenic microorganisms. The absence of reduction of the 8-nitrotrihalogenophenoxazinone substrates is rationalized according to their electronic properties and correlates well with previous findings. 相似文献
84.
Dong-Yi Li Shan Liang Jun-Hao Wen Ji-Xin Tang Shou-Long Deng Yi-Xun Liu 《Molecules (Basel, Switzerland)》2022,27(7)
Heat shock proteins (HSPs) are highly conserved stress proteins known as molecular chaperones, which are considered to be cytoplasmic proteins with functions restricted to the intracellular compartment, such as the cytoplasm or cellular organelles. However, an increasing number of observations have shown that HSPs can also be released into the extracellular matrix and can play important roles in the modulation of inflammation and immune responses. Recent studies have demonstrated that extracellular HSPs (eHSPs) were involved in many human diseases, such as cancers, neurodegenerative diseases, and kidney diseases, which are all diseases that are closely linked to inflammation and immunity. In this review, we describe the types of eHSPs, discuss the mechanisms of eHSPs secretion, and then highlight their functions in the modulation of inflammation and immune responses. Finally, we take cancer as an example and discuss the possibility of targeting eHSPs for human disease therapy. A broader understanding of the function of eHSPs in development and progression of human disease is essential for developing new strategies to treat many human diseases that are critically related to inflammation and immunity. 相似文献
85.
周期结构的晶格振动和分子的振动或转动谱,可以看作材料的特征指纹,拉曼散射正是探测这些振动的非常灵敏和有效的技术,因此它已经被广泛地应用到基础研究和工业生产的各个方面.而原则上,通过固体中的自由载流子或自旋与光的非弹性散射过程,人们也可以获得关于电子和磁激发的重要信息.文章对电子和磁的拉曼散射基本概念作了简要介绍,并对一些关联电子体系中的拉曼实验作了简要综述.特别是在非常规超导中,拉曼散射在确定超导能隙的大小和各向异性以及配对对称性等方面发挥了独特的作用. 相似文献
86.
87.
表面抛光可能给K9基片带来额外的杂质和吸收,分离K9基片的表面吸收率与体吸收率有助于改进基片的加工质量和抛光工艺,对抗损伤能力研究具有重要意义。分析了激光量热法测量弱吸收的原理,采用符合ISO 11551要求的激光量热计测量K9基片的弱吸收。对相同工艺抛光的不同厚度K9基片进行了弱吸收表征,实验发现K9基片的弱吸收随着厚度增加近似线性增大。推导了表面吸收率和体吸收率的计算式,实验得出本样品的表面吸收率为1.2110-5,体吸收率远大于表面吸收率,体吸收系数为1.7210-3/cm。实验结果显示所用K9样品的吸收主要来自于材料本身,改善抛光工艺对降低其吸收率作用不大。 相似文献
88.
Nanoimprint texturing of transparent flexible substrates for improved light management in thin‐film solar cells
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Karen Wilken Ulrich W. Paetzold Matthias Meier Nicole Prager Matthias Fahland Friedhelm Finger Vladimir Smirnov 《固体物理学:研究快报》2015,9(4):215-219
We present a nanoimprint based approach to achieve efficient light management for solar cells on low temperature transparent polymer films. These films are particularly low‐priced, though sensitive to temperature, and therefore limiting the range of deposition temperatures of subsequent solar cell layers. By using nanoimprint technology, we successfully replicated optimized light trapping textures of etched high temperature ZnO:Al on a low temperature PET film without deterioration of optical properties of the substrate. The imprint‐textured PET substrates show excellent light scattering properties and lead to significantly improved incoupling and trapping of light in the solar cell, resulting in a current density of 12.9 mA/cm2, similar to that on a glass substrate. An overall efficiency of 6.9% was achieved for a flexible thin‐film silicon solar cell on low cost PET substrate. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
89.
90.
Yen‐Teng Ho Chun‐Hao Ma Tien‐Tung Luong Lin‐Lung Wei Tzu‐Chun Yen Wei‐Ting Hsu Wen‐Hao Chang Yung‐Ching Chu Yung‐Yi Tu Krishna Prasad Pande Edward Yi Chang 《固体物理学:研究快报》2015,9(3):187-191
Layered growth of molybdenum disulphide (MoS2) was successfully achieved by pulsed laser deposition (PLD) method on c ‐plane sapphire substrate. Growth of monolayer to a few monolayer MoS2, dependent on the pulsed number of excimer laser in PLD is demonstrated, indicating the promising controllability of layer growth. Among the samples with various pulse number deposition, the frequency difference (A1g–E12g) in Raman analysis of the 70 pulse sample is estimated as 20.11 cm–1, suggesting a monolayer MoS2 was obtained. Two‐dimensional (2D) layer growth of MoS2 is confirmed by the streaky reflection high energy electron diffraction (RHEED) patterns during growth and the cross‐sectional view of transmission electron microscopy (TEM). The in‐plane relationship, (0006) sapphire//(0002)MoS2and sapphire//MoS2 is determined. The results imply that PLD is suitable for layered MoS2 growth. Additionally, the oxide states of Mo 3d core level spectra of PLD grown MoS2, analysed by X‐ray photoelectron spectroscopy (XPS), can be effectively reduced by adopting a post sulfurization process. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献