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71.
周继平 《数码设计:surface》2009,(11):193-195
要使完全没有色彩知识与造型意识的高等职业学校的学生,在不多的色彩课时计划内比较全面地了解和初步掌握色彩的基本表现技法,授课教师不但要有较深的色彩理论知识和过硬的色彩造型功底,还必须具有灵活多样的教学方法与实训指导技巧,更需要进行强化有效的实训教学手段。 相似文献
72.
这是一个被人誉为资讯爆炸的时代,这是一个他信力接近冰点的时代……生活在信息时代的人们,每天都接收到众多资讯,这些资讯涵盖大众生活的各个方面,商业、政治、体育、生活等。而大大小小的媒体每天将最新的新闻与资讯传达给大众时,也夹杂着它们对于新闻事件的观点和态度。 相似文献
73.
Haiping Wu Shun Huang Ying Zhu Jia Li Xiaoxiao Pang Yongyao Tang Siqiao Li Ping Ji Shijia Ding Wei Cheng Wenyang Li 《Advanced functional materials》2023,33(19):2212669
The accumulation of reactive oxygen species (ROS) and minimal osteogenic raw material in the osteoporotic bone microenvironment greatly inhibits the activity of osteoblasts. Herein, it is originally proposed to construct a biomatrix multifaceted bone microenvironment amendment -Mineralized zippered G4-Hemin DNAzyme hydrogel (MDH)-to improve osteoporotic osteogenic capacity and promote high-quality bone defect repair. The programmed design of the rolling circle amplified DNA hydrogel synthesis system allows the introduction of massive amounts of zippered G4-Hemin DNAzyme in MDH. The zippered G4-Hemin DNAzyme highly mimics the tight catalytic configuration of horseradish peroxidase and exerts excellent enzyme-like activity with considerable ROS molecule scavenging ability. In addition, the DNA amplification by-product pyrophosphate is ingeniously employed as a sufficient phosphorus source, thus constituting an autonomous mineralization system for waste reuse through the introduction of pyrophosphate hydrolase and calcium ions, which deposits in MDH as an osteogenic raw material and addresses the challenge of DNA hydrogel bio-application stability. The remarkable in vitro and in vivo outcomes demonstrate that MDH can effectively improve the oxidative stress status of osteoblasts, restore the balance of mitochondrial membrane potential, and reduce apoptosis, ultimately demonstrating superior osteogenic capacity. 相似文献
74.
75.
Tensile Strength Evolution and Damage Mechanisms of Al–Si Piston Alloy at Different Temperatures 下载免费PDF全文
Meng Wang Jianchao Pang Yu Qiu Haiquan Liu Shouxin Li Zhefeng Zhang 《Advanced Engineering Materials》2018,20(2)
76.
Andreas Goralczyk Sofya Savicheva Ramin Montazeri Simona Fine Fadoua Mayoussi Pang Zhu Kay Steffen Frederik Kotz-Helmer Dorothea Helmer Bastian E. Rapp 《Advanced Engineering Materials》2023,25(8):2201314
Superhydrophobic coatings are widely applicable, e.g., as self-cleaning surfaces or water–oil separation membranes, yet their wider usage is impeded due to costs of fabrication, size, or substrate limitation. Spray-coating is a versatile coating procedures and might offer a good solution for the fabrication of these superhydrophobic coatings, due to the fact that coatings can be fabricated on various materials in a simple, fast, and inexpensive manner. Most procedures rely on hybrid coatings of hydrophobized nanoparticles and a polymeric matrix, which have several drawbacks including the easy loss of nanoparticles and difficult waste handling. Here, the fabrication of the superhydrophobic material, called Fluoropor, for the first time, by spray-coating on various substrates including metals, tissues, concrete, and glass is presented. It is fabricated by spray-coating a mixture of a highly fluorinated monomer blended with porogens followed by photopolymerization. The superhydrophobicity of the material relies on the porous structure on the micro-/nanoscale across the bulk material and does not require any nanoparticles. Excellent self-cleaning ability of these coatings, resistance against thermal and abrasive impact, and their application as oil–water separation membranes are shown. This versatile applicability is highly promising for real-world application as self-cleaning coatings or oil–water separating membranes. 相似文献
77.
78.
Qunfeng Zeng Zhao Wang Wanjun He Zeming Pang Zekun Ning Ruiquan Chen Chenjie Zheng Chao Yan Leilei Guo 《Advanced Engineering Materials》2023,25(17):2300228
Ti6Al4V alloy has good corrosion resistance due to the formation of the passive oxide films on the surface of Ti6Al4V alloy. However, Ti6Al4V alloy has poor tribocorrosion resistance in the seawater environment. Herein the present work, plasma electrolytic oxidation (PEO) with the electrolyte of glycerol and sodium borate is used to generate PEO coatings on the surface of Ti6Al4V alloy to improve its tribocorrosion properties. The microstructure and tribocorrosion properties of PEO coatings are investigated by using scanning electron microscopy, X-ray diffraction, and tribometer, respectively. The growth kinetics and the tribocorrosion mechanisms of PEO coatings are discussed in detail. It is shown in the results that PEO coatings deposited on the surface of Ti6Al4V alloy are composed of rutile and anatase phases. The surface hardness and thickness of PEO coatings are enhanced with the increase of the voltage and time. The wear rate of Ti6Al4V alloy with PEO coatings is significantly reduced in artificial seawater. 相似文献
79.
基于静态路由的ISP负载均衡解决方案 总被引:1,自引:0,他引:1
传统的ISP负载均衡方法主要有2种,一是使用开启BGP协议的高端防火墙;二是使用专业负载均衡设备.本论文建立了1套新型的基于静态路由的ISP负载均衡解决方案.本文首先通过Whois协议获得ISP的AS号码,在公网BGP路由器数据库中根据这个AS号码查询属于不同ISP的全部BGP路由条目;之后将不同ISP(例如中国电信和中国联通)的路由条目导入园区网边界防火墙,使得用户访问实现负载分担和路由备份.本方案适用于大中型企业和大型居民小区园区网,相比传统的负载均衡方法,本方案能够节省大量设备投资. 相似文献
80.
In this paper, we introduce and study the multi-compartment capacitated arc routing problem—an extension of the classical capacitated arc routing problem, but where the required edges have a demand for different products, and multi-compartment vehicles are available to co-distribute these commodities. We present a local search algorithm that exploits well-known moves (2-opt, re-insert, relocate, exchange and cross). We take advantage of speed up tricks such as marking and neighbour lists, and we combine the procedure with the guided local search meta-heuristic in order to reach high quality solutions. We report on results from extensive computational experiments. Our aim is to reveal in what situations co-distribution by partitioned vehicles saves in routing costs as compared with separate distribution with un-partitioned trucks. We explore sensitivities in key problem characteristics including, the number of commodities, the vehicle capacity, the location of the depot and required edges, the density of required edges, and the demand per commodity for the required edges. 相似文献