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101.
钌基催化剂在低温和低压等温和条件下具有优异的催化性能,因而广泛应用于各种反应中。文章介绍了钌基催化剂的研究现状,着重探讨了其在加氢反应中的应用和研究进展,包括载体材料、前驱体和助剂对催化剂性能的影响。所涉及的反应包括:CO2加氢合成甲酸、CO/CO2甲烷化、苯加氢制环己烯、苯胺加氢制环己胺与二环己胺、多元醇加氢制备二元醇、葡萄糖加氢合成山梨醇等,并对它的应用前景进行了展望。 相似文献
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High burnup is a goal for further development of advanced nuclear power in the future. However, along with the increase of burnup, it becomes more diffidult to control reactor reactivity, which affects the operation safety of the nuclear reactor. Al2O3/B4C burnable poison materials widely used in pressurized water reactor currently will not meet the requirements of burnable poison materials in high burnup nuclear power. Because of the better performance of ZrO2/Gd2O3 burnable poison materials than that of Al2O3/B4C, this paper studies the preparation of ZrO2/Gd2O3 composite ceramic materials by the coprecipitation method. The experimental results show that at the sintering temperature of 1500–1650 °C, ZrO2/Gd2O3 composite ceramic grains are small, compact and uniform with the generation of homogeneous solid solution. At 1600 °C, ZrO2–10%Gd2O3 has the highest density and mechanical strength. 相似文献
104.
Wanting Li Zixuan Huang Rui Cai Wan Yang Huawei He Yejing Wang 《International journal of molecular sciences》2021,22(1)
Silver-based hybrid nanomaterials are receiving increasing attention as potential alternatives for traditional antimicrobial agents. Here, we proposed a simple and eco-friendly strategy to efficiently assemble zinc oxide nanoparticles (ZnO) and silver nanoparticles (AgNPs) on sericin-agarose composite film to impart superior antimicrobial activity. Based on a layer-by-layer self-assembly strategy, AgNPs and ZnO were immobilized on sericin-agarose films using the adhesion property of polydopamine. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray powder diffraction spectroscopy were used to show the morphology of AgNPs and ZnO on the surface of the composite film and analyze the composition and structure of AgNPs and ZnO, respectively. Water contact angle, swelling ratio, and mechanical property were determined to characterize the hydrophilicity, water absorption ability, and mechanical properties of the composite films. In addition, the antibacterial activity of the composite film was evaluated against Gram-positive and Gram-negative bacteria. The results showed that the composite film not only has desirable hydrophilicity, high water absorption ability, and favorable mechanical properties but also exhibits excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria. It has shown great potential as a novel antimicrobial biomaterial for wound dressing, artificial skin, and tissue engineering. 相似文献
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华为Com技术有限公司 《电力系统通信》2005,26(11):79-80
电力生产管理信息化支撑系统(电力数据网络)的安全一直是电力系统关注的重点.针对电力二次安全总体方案要求和特点,华为3Com技术有限公司推出了端点准入防御(EAD,Endpoint Admission Defense)解决方案.文章通过描述了EAD的基本原理、EAD作业流程、EAD在电力数据网络中的应用等角度入手,详细阐述了如何通过EAD解决方案来增强电力二次系统的网络安全. 相似文献
108.
Lingzhan Pan Huawei He Zhiwen Yao Zhiqing Chen Jingsong Liu Hualin Zhang Jun Yang 《武汉理工大学学报(材料科学英文版)》2010,25(3):484-486
A novel nano-hydroxyapatite (HA)/konjac glucomannan composite scaffold with high porosity was developed by blending nano-HA
particles with konjac glucomannan in alkaline solution. The scanning electron microscopy, porosity measurement, X-ray diffraction(XRD),
and Fourier transformed infrared(FTIR) spectroscopy were used to analyze the physical and chemical properties of the composite
scaffolds. The pure konjac glucomannan scaffolds and composite scaffolds were similar in their macroscopic morphology, however,
the microscopic morphology on porewall surfaces was quite different. The diffraction patterns of XRD revealed the presence
of konjac glucomannan and HA in the composite scaffolds. In addition, the results of FTIR also showed the existence of the
functional group of HA. These results reveal that the newly developed nano-HA/konjac glucomannan composite scaffold may serve
as a good three-dimensional substrate in bone tissue engineering. 相似文献
109.
为了验证三体滑行艇超高速航行能力,研究其阻力特征和船型特点,通过船模试验测量了不同排水量、重心位置下的阻力、纵倾角和升沉,研究了压浪条对阻力与航态的影响.试验结果表明:三体滑行艇2个辅助片体的存在加大了高速航行时气动升力的影响,改善了其水动力性能,具有优异的纵向稳定性和极小的兴波与喷溅,在Fr(v) >8条件下仍能稳定... 相似文献
110.
为准确分析特高压直流输电控制保护系统稳态运行与暂态过程的真实响应,在深入研究其分层控制机制和各控制环节原理的基础上,基于PSCAD/EMTDC平台建立实际控制保护系统的电磁暂态仿真模型,采用分时触发并行计算的方法完成各个子任务程序的同步计算,并对特殊功能模块、触发脉冲控制等关键环节进行程序设计。通过对模型进行大量的仿真测试并与实际录波对比,验证了仿真结果与实际动态响应的一致性。仿真模型已应用于锦屏—苏南特高压工程系统调试的分析计算中,也能为已投运及规划中的多条特高压直流的科学研究和工程计算提供重要技术支持。 相似文献