一种制做三维牙——颌骨光弹性模型的新方法

本文提出一种用“整体浇注法”制做三维牙——颌骨光弹性模型的新方法,即用价格便宜的石膏做阴模,先制出与真实牙几何相似的牙光弹性模型和模拟牙周膜的乳胶套,将它们粘接好,然后将其放入颌骨石膏阴模的适当位置,浇入环氧树脂混合液,用“二次固化法”进行固化,即可制成三维牙——颌骨整体光弹性模型。此法能保证模型与实物的严格几何相似和牙周的边界条件相似,使实验精度大大提高且工艺简单、成本低。     

不同活化剂对石油焦基活性炭孔结构的影响

以石油焦为原料 ,Na OH,KOH和 Na2 CO3 为活化剂制备活性炭 ,采用氮气吸附考察了不同活化剂对活性炭的比表面积、中孔和微孔孔径分布、孔容积及平均孔径等孔结构的影响 .结果表明 :KOH活化制备的活性炭包含 1 nm的微孔和 4nm的中孔 ,总孔容 0 .648cm3 /g,比表面积大 ;Na OH制备的活性炭以 1 nm的微孔为主 ,占总孔容 ( 0 .1 65 cm3 /g)的 98% ,平均孔径 1 .83nm;Na2 CO3 制备的活性炭以 4nm的中孔为主 ,占总孔容 ( 0 .1 43cm3 /g)的 68.5 % ,平均孔径 3.42 nm,比表面积小 .3种样品的孔径都呈现出多峰分布特征 .KOH和 Na2 CO3 活化制备的活性炭的 N2 吸附脱附曲线属于 型 ,Na OH活化制备的活性炭吸附脱附曲线属于 型 .     

持续发展是唯一出路

讨论了人类、环境与发展的关系，指出不适当的发展模式已使三者之间形成恶性循环，必须及时地改变发展模式。列举了中国面临的严重环境问题，指出只有走可持续发展的道路才是唯一出路。并提出为实施可持续发展应注意的６个主要问题。     

Hydrothermal products of the C3MS2-C12A7-MgO system

The autoclave products of reduced steel-slag of an electronic furnace mainly containing C₃MS₂ phase were detected. The hydrothermal products of this slag included calcio-chondrodite, brucite, and hydrogarnet phases. When suitable (CaO + MgO)/SiO₂ molar ratios were chosen, C₃MS₂ can react with SiO₂ to produce calcium silicate hydrates tobermorite, xonotlite, gyrolite, and truscottite phases with different saturated water vapor pressures. The phase brucite was present along with tobermorite, whereas phases Mg-xonotlite, Mg-gyrolite, and Mg-truscottite can rarely coexist with brucite. Hydrogarnet phase disappeared when Mg-truscottite was formed.     

离子色谱法测定配煤、焦炭和焦油中的氯含量

研究了用带电导检测器的离子色谱对配煤、焦炭和焦油中的Cl- 进行测定的方法。在YSA型8126A-4# 阴离子分离柱上用3.5mmol/LNa2CO3、5.3mmol/LNaHCO3做淋洗液对Cl-进行测定,方法简便快速。Cl-的检出限为2×10-6。该法也适用于F-、NO2-、NO3-、SO42-等的测定。     

几种表面活性剂在香精产品中的应用

本文阐述了几种表面活性剂在香精中应用的调配研究过程以及期间出现的不同现象,并对其进行了对比、比较.细述了这几种表面活性剂在应用过程中所出现的不同特征.     

A Non-Line-of-Sight mitigation localization algorithm for sensor networks using clustering analysis

Non-Line-of-Sight propagation of wireless signal has an impact on measured distances in range-based localization and will bias the final localization results. A new localization algorithm is proposed in this paper to mitigate Non-Line-of-Sight errors when there are more than enough anchor nodes deployed around the node to be located. This algorithm utilizes multi-round clustering analysis to filter the pre-located estimators which derive from all possible subsets of measured distances. In each round, the method density-based spatial clustering of applications with noise is adopted. Simulations show that the proposed algorithm can effectively improve localization accuracy not only when the measured distances with Non-Line-of-Sight error are minor but also under the condition that all of them suffer random Non-Line-of-Sight error.     

基于SOAP的企业异构信息系统集成

阐述了SOAP通信协议的构成和实现机制以及与相似协议的比较。基于它的跨平台的能力,将其运用于企业的分布式环境中,实现了异构信息系统间的互操作和跨部门的数据处理,提高企业数据处理的效能,同时为企业异构信息系统集成提供了新的方法。