罗门哈斯欲提升国内涂料行业整体素质国内首家涂料涂装教育网站正式开通

近日，国内第一个以教育为主要目的，专业指导内外墙装饰、装修和正确选用、使用高质量乳胶漆产品的专业中文网站http://www.paintquality.com.cn由罗门哈斯乳胶漆质量学院（Paint Quality Institute）在北京正式开通。该网站是联系广大消费者、涂料销售人员、建筑设计人员以及建筑装修施工人员的最佳窗口和途径。　　该网站包括首页、涂料销售人员、装饰装修公司、自己动手、建筑/室内设计师、涂料信息/图书馆等板块，各栏目内容针对不同人士的需求，提出建议，教育消费者选择优质涂料，最大限度的发挥涂料的创造性潜能。其中的有问…     

王东从容面对发展

其实王东始终不同意报道他。自2003年王东上任北京金隅集团董事长职位以来,这位少壮派企业领袖一直保持低调,媒体上鲜有他个人的采访报道。然而这两年,报刊杂志电视等媒体中有关金隅的报道频频出现,“北京金隅”几个字在北京东南西北的地标建筑上越来越多。北京人几乎都知道“金隅”。更多的人是由北京金隅集团赞助北京男篮“南征北战”时知道了金隅。但北京金隅究竟是做什么的?金隅是建材企业——许多人都这么认为。也确实,金隅出身于建材。北京金隅集团的前身是北京建材局改制而成的北京建材集团,经过这10多年的改革和几代人的努力,现在的…     

河北省金源加油站水塔的纠偏加固

介绍了一个水塔倾斜 18.6‰之后的纠偏施工。采用于其基础 (整板基础 )下直接掏土促使回倾 ,再用锚杆静压固定 ,纠偏施工十分成功。     

浅析“线”的特质与空间环境设计

“线”（又称“线条”）在任何艺术设计作品中都可以找到它的踪影,它是设计的基本元素之一.根据“线”存在的状态,可以将“线”分为空间中实体的“线”和虚拟的“线”，实体的“线”。     

Effect of Performance Model Accuracy on Optimal Pavement Design

In the first part of this paper, an analysis of the data collected during the American Association of State Highway Officials (AASHO) road test, based on probabilistic duration modeling techniques, is presented. Duration techniques enable the stochastic nature of pavement failure time to be evaluated as well as censored data to be incorporated in the statistical estimation of the model parameters. The second part of this paper presents the use of economic optimization principles for determining the optimal design of flexible pavements. We study the effect of deterioration model accuracy on optimal design and lifecycle costs by comparing three models. The first is a simple regression model developed by the AASHO, which forms the basis of design standards in use today. The second is a regression model that was developed with the same AASHO data set, but that includes a correction for data censoring. The third model is the probabilistic model developed in the first part of this paper. The results show that the AASHO model, when used as an input to lifecycle cost minimization, produces a pavement structural number that is lower than that produced by using the other two deterioration models. This results in shorter pavement lives and higher costs due to more frequent resurfacing. The savings in lifecycle cost accrued by using optimal structural number are shown to be quite significant, offering a sound basis for revising current design practices.     

水下发动机复合壳体一体化设计技术

介绍了水下发动机复合壳体一体化设计新技术,对其耐外压性能进行了仿真计算,并对发动机尾罩耐压性能和防渗性能进行了试验验证。结果表明,水下发动机可以采用以玻璃钢为主体材料的一体化复合壳体,在有效减小发动机质量和体积的同时实现水下密封,可广泛应用于水下高速航行器设计。     

Exif数据格式浅析及其读取应用

照片中镶嵌着丰富的Exif信息,从中可提取出拍摄位置与时间等实用数据服务于我们的工作与生活。本文分析了Exif数据格式,介绍了其读取方法,总结了Exif信息提取算法。结合具体实例,进行测试验证,对日常手机定位精度情况进行了评估。最后,通过生产实践,验证Exif信息对于提高测绘与地理信息单位的作业效率与质量控制的促进作用,同时对应用前景进行了展望。     

浅谈RAII惯用法

RAII使用对象在构造时获取资源,在对象生命期控制对资源的访问使之始终保持有效,最后在对象析构时释放资源.当处理配对获取/释放函数调用的资源时,应将资源封装在对象中,实现自动资源释放.通过使用不同RAII类型,可避免程序员忘记关闭端口引起的资源泄漏,还可确保异常发生时栈展开过程中自动释放端口资源.     

钠离子电池用电解质钠盐的研究进展

综述近年来含氰基类钠盐、酰胺类钠盐和氟类咪唑衍生物钠盐等电解质钠盐在钠离子电池中的研究应用。分析这些电解质钠盐的结构特征,阐述钠盐因独特结构优势提升电池性能的机理,展望钠离子电池电解质中钠盐的发展趋势。     

Ultrafast terahertz responses in monolayer graphene

ABSTRACT

We theoretically investigate the ultrafast terahertz (THz) properties of monolayer graphene. The analytical formulations of the photon carrier, electric polarization and optical current are obtained by solving the Bloch-equations in present of the ultrafast THz Gaussian pulse. Graphene shows a large nonlinear and ultrafast optical response at THz frequencies due to the gapless and relativistic Dirac particles with nearly linear energy dispersion. It is found that the photon carrier density, electric polarization and optical current density increase with increasing the frequency of the THz pulse. These theoretical results are in agreement with recent experimental findings. This study confirms further that graphene exhibits important features and is relevant to the applications in the ultrafast THz fields.