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.     

高压旋喷锚杆在黄土深基坑支护中的模拟研究

为了研究高压旋喷锚杆支护体系在黄土深基坑工程中的工作性状,选取西安某深基坑支护工程为研究对象,运用MIDAS/GTS软件对该支护体系进行了有限元数值模拟,并与二次注浆锚杆支护体系的模拟结果进行了对比分析。结果表明:两种基坑支护方式均可满足该基坑支护的技术要求,但采用高压旋喷锚杆支护时,需要锚杆的总长度为二次注浆锚杆长度的62%,且高压旋喷锚杆筋体可实现回收,降低了锚杆施工对周围土层的干扰,其在黄土地区高边坡及深基坑支护工程中有着广阔的应用前景。     

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.     

Acidic and catalytic properties of niobic acid crystallized at low temperature

Niobic acid was crystallized at 120 °C for 48 h, which showed the largest acid amounts at higher acid strengths. The crystallized niobic acid calcined at 300 °C was found to show higher activity than uncrystallized niobic acid and niobic acid washed with water or treated with sulfuric acid or phosphoric acid for the dehydration of isopropanol and the esterification of ethanol with acetic acid.     

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。     

Dynamics modeling and analysis of a flexible-base space robot for capturing large flexible spacecraft

Space robots are in huge demand due to the rapid growth of their service targets, i.e., spacecraft. There are generally large flexible components on spacecraft, such as antenna reflectors and solar paddles. Due to the vibratility of their structure, it is challenging for a space robot with flexible appendages (the base is then called flexible-base) to capture and repair the large flexible spacecraft. After capturing, the two spacecraft with flexible appendages are connected by a space manipulator, and a compounded system is formed. In this paper, we developed a dynamic model and a closed-loop simulation system, to provide a means to verify path planning and control algorithms. Initially, the dynamic characteristics of different capturing stages (preimpact and post-impact) were analyzed. The topologies of a flexible-base space robot and the compounded system were described based on incidence and channel matrices. Secondly, the recursive dynamics was formulated and resolved by an effective numerical method. The modeling was verified by Adams’ model. Thirdly, we implemented a dynamics calculation block in Matlab/Simulink environment using the S-function package for the C program, and developed a closed-loop simulation system, which was composed of the Planning and Controller, the Multibody Dynamic, and the 3D Display modules. Finally, based on the simulation system, two typical missions—target berthing and on-orbital manipulation of the target along a circle, were simulated and evaluated. Dynamics analysis results presented some useful rules for the path planning and control to suppress the vibration of the flexible structure.