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131.
研究了镁砂及烧成温度对镁质滑板高温性能的影响。结果表明 :以ω(MgO)≥ 98%、C/S≥ 3、晶粒直径≥ 5 0 0 μm的高纯镁砂为内层料 ,以中低档镁砂为外层料 ,用纸浆废液作结合剂 ,直接复合成型的镁质滑板经 16 5 0℃左右的高温烧成后 ,性能指标达到外商订货要求 ,不经浸油、打箍 ,在国外 385t连铸钢包批量试用成功。 相似文献
132.
塑料挤出机主辅电机联动系统设计 总被引:1,自引:0,他引:1
本文在分析国内外挤出机生产线主辅电机同步联调特点的基础上,提出了一种实用的联调控制系统设计方案,控制系统设计采用纯硬件方式,可以广泛适用于国内未采用同步联调技术的挤出生产线,进行技术改造,对原有设备改动极小,具有很高的性能/价格比。 相似文献
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Design of S‐Allylcysteine in Situ Production and Incorporation Based on a Novel Pyrrolysyl‐tRNA Synthetase Variant 下载免费PDF全文
Dr. Matthias P. Exner Tilmann Kuenzl Tuyet Mai T. To Zhaofei Ouyang Sergej Schwagerus Michael G. Hoesl Prof. Dr. Christian P. R. Hackenberger Prof. Dr. Marga C. Lensen Prof. Dr. Sven Panke Prof. Dr. Nediljko Budisa 《Chembiochem : a European journal of chemical biology》2017,18(1):85-90
The noncanonical amino acid S‐allyl cysteine (Sac) is one of the major compounds of garlic extract and exhibits a range of biological activities. It is also a small bioorthogonal alkene tag capable of undergoing controlled chemical modifications, such as photoinduced thiol‐ene coupling or Pd‐mediated deprotection. Its small size guarantees minimal interference with protein structure and function. Here, we report a simple protocol efficiently to couple in‐situ semisynthetic biosynthesis of Sac and its incorporation into proteins in response to amber (UAG) stop codons. We exploited the exceptional malleability of pyrrolysyl‐tRNA synthetase (PylRS) and evolved an S‐allylcysteinyl‐tRNA synthetase (SacRS) capable of specifically accepting the small, polar amino acid instead of its long and bulky aliphatic natural substrate. We succeeded in generating a novel and inexpensive strategy for the incorporation of a functionally versatile amino acid. This will help in the conversion of orthogonal translation from a standard technique in academic research to industrial biotechnology. 相似文献
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Cover Picture: Design of S‐Allylcysteine in Situ Production and Incorporation Based on a Novel Pyrrolysyl‐tRNA Synthetase Variant (ChemBioChem 1/2017) 下载免费PDF全文
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K. Xiao Y. P. Zhao G. Ouyang X. L. Li 《Journal of Coatings Technology and Research》2017,14(6):1297-1306
Wetting behaviors on a hydrophobic nanopatterned surface, which are of primary consideration in the design of superhydrophobic surfaces, are studied on an analytic model that shows the hole-patterned substrate is more favorable for water droplets to nucleate on the inside of holes based on nucleation theory. After droplet nucleation, the transition from Wenzel state to Cassie–Baxter state may occur during the growth stage. The calculation of the free energy of droplets during the growth stage indicates that the wetting transitions depend on the volume of the droplets, and Wenzel state or Cassie–Baxter state depends on the absolute size and relative size of the geometrical morphology of the nanoholes. 相似文献
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Y.M. Wang H. Tian X.E. Shen L. Wen J.H. Ouyang Y. Zhou D.C. Jia L.X. Guo 《Ceramics International》2013
An infrared emissivity coating material containing γ-Al2O3 was prepared on 2024 aluminium alloy surface by the microarc oxidation (MAO) method. The microstructure of the coatings was analysed by SEM, XRD and EDS techniques. The infrared emissivity properties tested at 500 °C were investigated by an infrared radiometer based on a Fourier transform infrared spectrometer. The results show that the infrared emissivity values of coated Al samples depend on the phase composition and surface roughness of the coatings. Corresponding to increasing coatings thickness, the gradually increasing γ-Al2O3 content and some oxide compounds containing Si and P contribute to the higher infrared emissivity value (about 0.85) in the wavelength range of 8–20 μm. The increasing surface roughness leads to an obvious increase in emissivity from 0.2 to 0.4 at wavelength 3–5 μm. 相似文献