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71.
刘剑锋 《网络安全技术与应用》2012,(11):69-70
本文主要分析在数字化校园背景下,人事管理工作为什么要实现信息化以及人事管理系统建设的具体方案。 相似文献
72.
吕廷军 《计算机光盘软件与应用》2012,(3):246-247
《数字电路》是中职电类专业的一门专业基础课程。结合目前中职学校教学现状中存在的问题,如何让学生把这门课学好,笔者从精选教材、课堂导入、教学手段、考核评价等方面进行了探讨。指出了只有充分激发起学生的学习兴趣和学习积极性,才是提高教学质量的关键。 相似文献
73.
电流密度对声电沉积生物活性透钙磷石涂层结构和形貌的影响 总被引:5,自引:0,他引:5
通过声电沉积工艺在碳/碳复合材料表面制备了生物活性透钙磷石涂层,采用SEM、FFIR、XRD研究了超声场中电流密度对涂层组成结构和形貌的影响。发现在一定工艺条件下,随电流密度增加,涂层的平均晶粒尺寸减小,致密度增加;当电流密度小于l0mA/cm^2时涂层形貌为片状,l0mA/cm^2-26mA/cm^2时为粒状,32mA/cm^2时为花菜心状。且涂层中透钙磷石晶体的择优取向也发生变化,择优晶面依次为(021)、(111)、(220)。同时还讨论了涂层微观结构变化机理。 相似文献
74.
Ma Xin Zhang Guoqiang Li Fengting Jiao Mingyang Yao Shunyu Chen Zhipeng Liu Ziyong Zhang Yongyu Lv Ming Liu Licheng 《Catalysis Letters》2021,151(10):2939-2949
Catalysis Letters - Microbial electrosynthesis (MES) is an effective approach to driving the CO2 reduction to multi-carbon organic products using renewable energy. In this work, the MES of acetate... 相似文献
75.
在极软岩的地质条件下,采用自创的新型注浆设备,通过不同入岩深度及成桩措施进行桩基施工,根据静载荷试验进行分析对比,得出入岩深度增加和后注浆对桩基沉降量的影响及自创注浆设备的实用性. 相似文献
76.
Li Yingwei Wang Xueyao Duan Guan Chen Zeji Jin Jianfeng 《Journal of Electroceramics》2021,47(4):124-133
Journal of Electroceramics - The effect of crystallographic structure and texture on the fracture behavior of lead zirconate titanate (PZT) ceramics was investigated. PZT ceramics with Zr/Ti ratio... 相似文献
77.
Yan Cui Zequan Zeng Jianfeng Zheng Zhanggen Huang Jieyang Yang 《Frontiers of Chemical Science and Engineering》2021,15(5):1125
To realize the utilization of visible light and improve the photocatalytic efficiency of organic pollutant degradation in wastewater, a nitrogen-doped titanium-carbon composite (N-TiO2/AC) prepared by sol-gel methods was applied in the photodegradation of phenol assisted by persulfate under visible light irradiation (named N-TiO2/AC/PS/VIS). The results show that a synergistic effect exists between visible-light photocatalysis and persulfate activation. Compared with TiO2/PS/VIS, the phenol degradation rate was found to be observably improved by 65% in the N-TiO2/AC/PS/VIS system. This significant increase in degradation rate was mainly attributed to the following two factors: 1) The N and C doping can change the crystal structure of TiO2, which extends the TiO2 absorption wavelength range to the visible light region. 2) As an electron acceptor, PS can not only prevent electrons and holes from recombining with each other but can also generate strong oxidizing radicals such as ∙SO4– and ∙OH to accelerate the reaction dynamics. The process of phenol degradation was found to be consistent with the Langmuir pseudo-first-order kinetic model with an apparent rate constant k of 1.73 min–1. The N-TiO2/AC/PS/VIS process was proven to be a facile method for pollutant degradation with high pH adaptability, excellent visible-light utilization and good application prospects. 相似文献
78.
The efficient separation of water-in-oil emulsion is of significance in environment and energy filed, and it has become a world-wide challenge. Herein, we have presented a one-step, facile and low-cost approach to prepare superhydrophobic sands for efficient separation of water-in-oil emulsion. The as-prepared sand layers possessed a water contact angle higher than 151°, demonstrating their superior superhydrophobic property. Besides, the as-prepared sand layers could separate water-in-emulsions with separation efficiency up to 99.7%, which is superior to both traditional and superwettable filtration membranes. The effect of thickness of sand layer on separation performance was also investigated. The results showed that the filtration flux decreased with the increased of filtration thickness while the separation efficiency increased. The as-prepared sand layer proposed by this study is a processing candidate for separating water-in-oil emulsion in practical industry. Additionally,the as-prepared superhydrophobic sand fabrication method also provides an alternative for desert water storage. 相似文献
79.
Lei Ma Hongxia Lv Haonan Yu Lingtong Kong Rongyue Zhang Xiaoyan Guo Haibo Jin Guangxiang He Xiaoyan Liu 《中国化学工程学报》2021,33(5):286-296
A series of high oil-absorption resins with low cross-linking degree were synthesized by suspension polymerization using stearyl methacrylate(SMA), 2-Ethylhexyl methacrylate(EHMA), and styrene(St) as monomers.Response surface methodology(RSM) with central composite design(CCD) was also applied to determine the optimal parameters that are mainly known to affect their synthesis. Thus, the effects of the monomer mass ratio(EHMA:SMA), the rigid monomer(St) dosage, the porous agent(acetone) dosage, and their pairwise interaction on the resin's oil-absorption capacity were analyzed, highlighting PSES-R_2 as the resin with the optimum performance. The pure oil-absorption rates of PSES-R2 for gasoline, diesel, and kerosene were 11.19 g·g~(-1),16.25 g·g~(-1), and 14.84 g·g~(-1), respectively, while the oil removal rates from oily wastewater were 98.82%,65.11%, and 99.63%, respectively. 相似文献
80.
通过对直流电流互感器阶跃特性测试技术和暂态特性建模的分析研究,提出了特高压直流电子式互感器阶跃特性智能化测试方案及现场测试解决方案,对改变目前直流输电工程中互感器选型、检测、运维的无序状态具有十分重要的意义,将为直流控制保护及监视系统的可靠运行提供技术保障,提高了直流输电工程的安全可靠运行水平. 相似文献