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51.
用水热盐溶液水解法可合成含有单斜相晶态纳米ZrO2颗粒的ZrO2溶胶体.用匀胶法制备的纳米ZrO2薄膜厚度约160
nm,折光率为1.56.纳米ZrO2薄膜表面质量良好,无表面裂隙,台阶仪研究表明薄膜表面粗糙度算术差Ra=2.7
nm,均方根差Rq=3.7 nm.以ZrO2为高折射率膜层,碱催化的溶胶凝胶SiO2为低折射率膜层,制备了SiO2/ZrO2多层高反射率薄膜,10周期的SiO2/ZrO2多层膜系,在1.06
μm波段处透过率为1%,薄膜表面抗激光损伤阈值约15 J/cm2(1.06 μm,2.5 ns高功率激光作用下). 相似文献
52.
Mühlberger Andreas; Bülthoff Heinrich H.; Wiedemann Georg; Pauli Paul 《Canadian Metallurgical Quarterly》2007,19(3):340
An overall assessment of phobic fear requires not only a verbal self-report of fear but also an assessment of behavioral and physiological responses. Virtual reality can be used to simulate realistic (phobic) situations and therefore should be useful for inducing emotions in a controlled, standardized way. Verbal and physiological fear reactions were examined in 15 highly tunnel-fearful and 15 matched control participants in 3 virtual driving scenarios: an open environment, a partially open tunnel (gallery), and a closed tunnel. Highly tunnel-fearful participants were characterized by elevated fear responses specifically during tunnel drives as reflected in verbal fear ratings, heart rate reactions, and startle responses. Heart rate and fear ratings differentiated highly tunnel-fearful from control participants with an accuracy of 88% and 93%, respectively. Results indicate that virtual environments are valuable tools for the assessment of fear reactions and should be used in future experimental research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Mariarosaria De Falco Alessandra Porritiello Federica Rota Viviana Scognamiglio Amina Antonacci Giovanni del Monaco Mariarita De Felice 《International journal of molecular sciences》2022,23(5)
Generation of the 3′ overhang is a critical step during homologous recombination (HR) and replication fork rescue processes. This event is usually performed by a series of DNA nucleases and/or helicases. The nuclease NurA and the ATPase HerA, together with the highly conserved MRE11/RAD50 proteins, play an important role in generating 3′ single-stranded DNA during archaeal HR. Little is known, however, about HerA-NurA function and activation of this fundamental and complicated DNA repair process. Herein, we analyze the functional relationship among NurA, HerA and the single-strand binding protein SSB from Saccharolubus solfataricus. We demonstrate that SSB clearly inhibits NurA endonuclease activity and its exonuclease activities also when in combination with HerA. Moreover, we show that SSB binding to DNA is greatly stimulated by the presence of either NurA or NurA/HerA. In addition, if on the one hand NurA binding is not influenced, on the other hand, HerA binding is reduced when SSB is present in the reaction. In accordance with what has been observed, we have shown that HerA helicase activity is not stimulated by SSB. These data suggest that, in archaea, the DNA end resection process is governed by the strictly combined action of NurA, HerA and SSB. 相似文献
54.
作为现代企业管理的一个重要组成,人力资源管理对优化企业资源配置、降低企业管理成本、提高企业管理效率等方面具有关键作用。伴随着信息化技术的不断发展,人力资源管理信息化技术和水平也日益完善。人力资源管理信息化对于改变企业传统人力资源管理观念和方法,有效的将企业人力、财力、物力以及信息的结合,实现企业管理信息化具有积极意义。本文就是在介绍人力资源信息化管理现状基础上,对人力资源管理信息化系统含义和作用进行分析,着重探讨了人力资源管理信息化系统设计方案。 相似文献
55.
56.
HR3C钢管因具有优良的抗蒸汽氧化性能广泛应用于566、600及620 ℃等级超/超超临界机组,但是其在高温时效过程中表现出明显的脆化现象,严重影响机组安全稳定运行。结合脆化失效案例的典型特征对HR3C钢管在高温时效和服役态下的脆化现象、脆化机理、脆化防治进行了系统的分析,提出了针对脆化HR3C钢管泄漏的预防性措施。最后指出了HR3C钢的应用困境和面临的挑战。 相似文献
57.
Adam K. Budniak Niall A. Killilea Szymon J. Zelewski Mykhailo Sytnyk Yaron Kauffmann Yaron Amouyal Robert Kudrawiec Wolfgang Heiss Efrat Lifshitz 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(1)
Layered semiconductors have attracted significant attention due to their diverse physical properties controlled by composition and the number of stacked layers. Herein, large crystals of the ternary layered semiconductor chromium thiophosphate (CrPS4) are prepared by a vapor transport synthesis. Optical properties are determined using photoconduction, absorption, photoreflectance, and photoacoustic spectroscopy exposing the semiconducting properties of the material. A simple, one‐step protocol for mechanical exfoliation onto a transmission electron microscope grid is developed, and multiple layers are characterized by advanced electron microscopy methods, including atomic resolution elemental mapping confirming the structure by directly showing the positions of the columns of different elements' atoms. CrPS4 is also liquid exfoliated, and in combination with colloidal graphene, an ink‐jet‐printed photodetector is created. This all‐printed graphene/CrPS4/graphene heterostructure detector demonstrates a specific detectivity of 8.3 × 108 (D*). This study shows a potential application of both bulk crystal and individual flakes of CrPS4 as active components in light detection, when introduced as ink‐printable moieties with a large benefit for manufacturing. 相似文献
58.
陈巍 《常州信息职业技术学院学报》2009,8(2):83-85
人力资源外包是社会化大生产细化的产物,随着大学生就业的不断市场化和企业非核心业务外包趋势的不断加强,人力资源外包服务公司逐渐在大学生就业市场上活跃起来。对此,分析了其产生的背景、现状、对大学生就业市场的促进作用以及目前存在的问题,并展望了人力资源外包在大学生就业市场上的前景。 相似文献
59.
分析了膜厚控制误差对反射膜设计曲线的影响,发现高低折射率材料厚度反方向变化时(高折射率膜层厚度增加,低折射率膜层厚度减小),反射膜的反射率变化不明显,设计的膜系结构对这种膜厚变化方式的制造误差宽容.在此基础上制备了193nm反射膜,结果表明退火前光学损耗相对较大,实验结果与理论计算结果存在一定差距,并且散射损耗在总的光学损耗中所占比例很小,而吸收损耗占光学损耗的主要部分,起主导作用.退火后光学损耗明显下降,实验结果与理论计算结果更为接近,193nm反射膜的反射率达98%以上.散射损耗增加至接近吸收损耗的水平,不过在总的光学损耗中仍然占比较小的比例.说明当吸收损耗下降到一定程度时,散射损耗所起的作用也是不可忽视的. 相似文献
60.