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811.
对用后铝镁碳砖再生颗粒料的组成和结构特点进行显微分析,并通过改变混料方式以及不同粒度再生料的加入量研究假颗粒对再生铝镁碳制品结构与性能的影响.结果表明:用后铝镁碳砖再生料中含有约40%与废砖相组成和结构相似、骨料与基质并存于同一颗粒的二次颗粒,即所谓的"假颗粒",假颗粒的组成、结构及外形的均匀程度均远不如一次骨料颗粒;混碾可使用后铝镁碳砖再生料中假颗粒发生二次破碎,且粒度越大,发生二次破碎的颗粒数量越多;假颗粒二次破碎导致再生制品的粒度组成发生改变,进而影响其密度和耐压强度. 相似文献
812.
钱谦益唐宋兼宗的祈向与清代诗风新变 总被引:4,自引:0,他引:4
罗时进 《杭州师范学院学报(社会科学版)》2001,(6):67-71
“诗必盛唐”是明代具有强势传播力的诗学观念 ,其消极影响是法唐而赝 ,自狭诗道。当时虽有接纳宋诗的呼唤 ,但难以形成趋势。明末清初 ,钱谦益以唐宋兼宗为新的诗学选择 ,具体途辙是以崇尚杜诗为由唐向宋的起点 ,在诗坛大力导入宋代诗风 ,融铸异质 ,求变创新。以沉潜深厚改变浮薄肤浅 ,以性情为本取代唯务格调 ,从而形成宏衍阔大的气局 ,使诗歌创作具有多元组合的美质。钱氏的这一诗学选择开启了清代新诗风 相似文献
813.
This paper studies the practical generation of Voronoi diagrams for multiply-connected planar areas bounded by line segments. The core of the algorithm was calculating Voronoi polygon of every Voronoi object in planar areas independently. The main approach had two steps. The first step was calculating all relevant bisectors of every Voronoi object. The second was combining obtained bisectors into completed Voronoi polygons individually. All code was implemented in Visual C++ platform. The resulting code was extensively tested in real-world data and its practical running time grew only linearly. Three statistical CPU-consumption charts had been drawn with the Voronoi diagrams computation data, and compared with other published codes for computing Voronoi diagrams. The algorithm was applied to compute offsetting of slice area consisting of large-scale line segments for the selective laser melting (SLM) trajectory scanning technology which is a kind of rapid prototyping (RP). The experimental results of offsetting for slice area based on Voronoi diagrams show that the approach is effective and simple for polygon offsetting problems. The method is helpful to those offsetting work and can provide more effective offsetting solution. 相似文献
814.
Superhydrophobic silver nanocoatings with feather-like morphology are fabricated on copper substrates by electroless galvanic deposition. The coating exhibit superhydrophobicity with a contact angle of 156.4° and glide angle of 4° without any further surface modification. Scanning electron microscope (SEM), X-ray diffraction (XRD) and contact angle measurements are used to investigate the morphology, crystal structure and superhydrophobicity, respectively, of the coatings. The coatings exhibit high thermal stability; their water contact angle did not change when the coatings were heated to 200°C for 2 h. The mechanism of superhydrophobicity of the silver coating is discussed based on the work of Amirfazli, Wenzel and Cassie. 相似文献
815.
毒理学是关系人类健康的一门学科,人类与毒物斗争的历史是人类文明史中重要的篇章.生物学研究的每一次进展都使得毒理学产生新飞跃,从五四运动至今的90多年内,我国现代毒理学发展经历了起步、取得阶段性成果和开拓创新三个不同的发展阶段. 相似文献
817.
水泥粉磨系统是水泥生产过程中的重要环节.在保证水泥质量的情况下,最大限度地降低粉磨系统的能耗对于节约能源及提高企业经济效益具有重要的现实意义.本文介绍了目前水泥粉磨设备的选型情况,并提出选用立磨终粉磨系统将成为水泥粉磨的发展趋势. 相似文献
818.
To compare two microspheres of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin loaded theophylline as pulmonary sustained drug delivery carriers, the characteristics and ciliotoxicity were
studied. The drug loadings of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin microspheres were 21.09% and 21.42%, and the encapsulation efficiencies were 91.40% and 92.80%. The distributions
of 50% (d
0.5) of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin microspheres were 4.89 and 5.83 μm, respectively. Both microspheres showed spherical shape with smooth or wrinkled
surfaces. FT-IR of chitosan/β-cyclodextrin microspheres demonstrated that theophylline had formed hydrogen bonds with chitosan and β-cyclodextrin, while for the carboxymethyl chitosan/β-cyclodextrin microspheres theophylline had interaction with carboxymethyl chitosan. The moisture absorption showed that an
equilibrium was reached within 24 h. The two microspheres possessed better adaptability. In vitro release of theophylline from chitosan/β-cyclodextrin microspheres was slower than that from carboxymethyl chitosan/β-cyclodextrin microspheres at pH 6.8.
Biography: LI Ruobao(1968–), male, Associate professor, research direction: foundation research of respiratory system. 相似文献
819.
万师 《武汉科技学院学报》2013,26(4):42-45
《三字经》高度浓缩着中国传统文化的和谐价值思想,通过辩证逻辑的方法,具体分析了其中蕴含的生态伦理因素,独创性的探索《三字经》中人与自然的和谐环境、和谐的社会环境、"诚信"的人际环境的内涵,其目的在于突破传统启蒙读物的伦理水平,更好地促进社会主义和谐社会的建设,对文化的支撑、道德的修养、学习的提升起到了有益的借鉴。 相似文献
820.
A representation method using the non-symmetry and anti-packing model (NAM) for data compression of binary images is presented.The NAM representation algorithm is compared with the popular linear quadtree and run length encoding algorithms.Theoretical and experimental results show that the algorithm has a higher compression ratio for both lossy and lossless cases of binary images and better reconstructed quality for the lossy case. 相似文献