容错服务器冗余系统在煤矿综合自动化中的应用

论述了煤矿综合自动化系统的重要性和组成部分,分析了当前煤矿综合自动化系统中前台服务器的2种运行方式——双机热备系统和容错服务器冗余系统,并对2种运行方式的设备性能、优缺点、日常维护工作量等方面进行了对比,指出冗余服务器容错系统的特点。     

仪表供电系统UPS并机冗余隐患整治

介绍仪表供电系统UPS的供电方式,分析仪表供电系统UPS并联冗余系统的特点与存在的隐患,介绍系统性冗余和设备冗余理论,提出将UPS并联冗余系统改为双机分段供电方式的技术实施方案。完成改造后系统一次性投运成功,催化、重整加氢、柴油改质、气分MTBE装置仪表供电系统UPS并机冗余可靠性符合炼化板块电气管理的相关要求。     

基于PLC和组态软件的油库罐区监控系统

设计了基于S7—300系列PLC和力控组态软件的油库罐区监控系统,介绍了其硬件结构和软件设计。该系统通过工业以太网实现上位机和PLC的通信,采用上位机双机冗余和PLC软冗余结构,可以充分发挥PLC和计算机的优势,有助于提高监控系统的可靠性。     

不间断供电双机冗余并联技术的应用

介绍了双机冗余并联不间断供电系统的工作原理及优点,结合多年聚酯装置上的应用实践,阐述了这种运行方式的可靠性以及维护的方便性,并介绍了应用此连接方式的安装、使用、维护的注意事项。     

S7-414H在水处理中的开发和应用

S7-414H双机冗余控制系统由两台Advantech、S7-414H主站、ET200M从站和现场pH计、浓度、电导、流量、液位变送等子系统组成,现场模拟信号二次连接至ET200M站,核心系统通过工业以太网和Profibus DP实现数据交换,两台上位机通过网络平台对整个系统实施控制和管理,并与工厂中控室实现数据交换,形成集散型系统框架平台。该系统功能完善、技术指标先进、操作界面友好、使用维护方便,具有广泛的应用开发前景。     

基于PLC的井下助排剂生产线控制系统设计

针对某企业的井下助排剂生产线给出了一套井下助排剂生产监控系统的整体设计方案及控制方法。在对传统手动控制条件下的生产状况进行分析以后,设计了以西门子S7-300 PLC(Programmable Logic Controller)为控制核心、组态软件Win CC 7.4为上位监控的双机冗余数字化生产监控系统,对生产全过程进行自动监控、数据处理。该系统显著提高了设备数字化水平和助排剂产品生产效率,降低了工人的劳动强度,满足了企业的生产要求。     

基于Tricon SIS的加热炉BMS冗余通信系统

以某炼油厂加热炉为背景,在燃烧器管理系统(BMS)中设计实现了一套基于Tricon SIS的冗余通信系统。首先介绍冗余通信系统的功能和结构,然后详述Tricon系统多重冗余结构、CPU机柜和I/O机柜之间的冗余通信结构、CPU和触摸屏/工作站之间的冗余通信结构、BMS和DCS之间的冗余通信结构及其冗余通信系统的设计实现过程,最后进行冗余通信测试和总结。加热炉BMS冗余通信系统已经成功应用,可为其他类似项目提供参考和借鉴。     

Linux集群心跳检测方法的研究与实现

针对目前计算机领域中应用系统高可用性能的要求,以双机热备高可用系统为研究对象,在重点分析了心跳机制的基础上,介绍了L inux集群高可用系统及双机热备的基本原理,同时在L inux环境下利用heart-beat软件设计了一种心跳检测方法,并进行了验证测试。实际测试结果表明,该方法具有响应速度快、实时性好、可靠性高等特点,可以满足应用系统高可用性、提供不间断服务的要求。     

ControlLogix控制器冗余故障诊断与分析

介绍ControlLogix冗余系统的组成与工作原理,针对系统控制器冗余故障进行了分析,通过对冗余系统软、硬件的排查,分析了冗余故障产生的原因,并应用软件优化方法解决了系统冗余故障,提高了控制系统的可靠性和安全性。     

基于PC104的DCS冗余软件设计与实现

介绍DCS中冗余组态软件和冗余运行软件的设计与实现,包括冗余系统硬件结构、冗余系统软件结构、冗余参数组态、组态信息的存储、组态信息的下传通信、冗余运行软件切换控制逻辑、错误表管理、冗余运行软件与I/O模块的数据交换。这一软件实现能有效提高DCS在工业应用中的可靠性和安全性。     

Stability of granules of solid solutions of poly-pehnyleneterephthalamide

Conclusions Studies of starting solutions of PPTA in sulfuric acid and of granules obtained under pressrue at low temperature, and of granules stored in a hermetic package, have been carried out by the methods of differential thermal analysis, turbidity spectrum and viscometry.On granulation of a solidified PPTA solution, short-term storage of the granules in a hermetic package, or short contanct of the granulated mass with air, no appreciable change in melting point or of the intrinsic viscosity of the system takes place.Long storage of a granulated solution, even in hermetic packages, can lead to a considerable decrease in the melting point of the crystal solvates, caused by an increase in defectiveness of crystal structure under the effect of moisture.Translated from Khimicheskie Volokna, No. 3, pp. 25–26, May–June, 1986.     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

Analysis of products of high-temperature pyrolysis of various hydrocarbons

Ethane, ethylene, acetylene, propane and neopentane have been pyrolyzed at 1173 K, and methane at 1372 K in a flow system, and the volatile pyrolysis products analyzed. Eleven aromatic hydrocarbons, containing 14 or fewer carbon atoms, accounted for 98 + % of the liquid products recovered in each case. Benzene was the main product, followed by naphthalene. No compounds with branched chains or multiple substituents were present, and compounds containing even numbers of carbons comprised 93–99% of each mixture. Acetylene was a major component of the gaseous effluent from each of the initial hydrocarbons. The effect of temperature on the composition of the gaseous effluent during pyrolysis of methane, ethane and ethylene was determined. Carbon film deposition from methane commenced at about 1273 K; from ethane at 1015 K and from ethylene at 1100 K, in each instance coinciding with the appearance of acetylene in the effluent. As the temperature was raised, at first the increase in the rate of carbon deposition closely followed the increase in the concentration of acetylene in the effluent. It is proposed that acetylene may be a common factor in the pyrolysis of aliphatic hydrocarbons, perhaps acting as the precursor of both surface carbon and aromatic hydrocarbons by a process of head-to-tail linkage of two-carbon units at active surface sites to form chains that then undergo dehydrogenation to carbon or cyclization and desorption as aromatic species.     

Model of Cellular Instability of Flames of Ternary Mixtures

A simple phenomenological diffusive-thermal model of cellular instability of premixed flames of ternary mixtures is developed and presented. The model shows that preferential diffusion can alter stoichiometry of the mixture, i.e., the ratio of the fuel and oxidizer concentrations, and also its effective dilution by an inert. Key parameters of the model are estimated using numerical modeling of burning velocities. Laminar burning velocities are calculated for hydrogen-oxygen-nitrogen, methane-oxygen-nitrogen, and propane-oxygen-nitrogen mixtures. Conditions for the appearance of cellular instability in ternary mixtures are determined and compared with experiments. In good agreement with experimental observations, the diffusive-thermal instability is predicted in hydrogen flames with equivalence ratios φ ≲ 1.45, in lean methane flames with φ ≲ 1.02, and in rich propane flames with φ ≳ 1.03. The magnitude of the change in the local flame velocity due to preferential diffusion is evaluated. It is demonstrated that nitrogen diffuses faster than oxygen in hydrogen-air and methane-air flames, while oxygen diffuses faster than nitrogen in flames of propane and other heavier hydrocarbons. In mixtures of air with propane or heavier hydrocarbons, the transition between stable and unstable regimes is predicted in mixtures that are leaner than the mixture corresponding to the peak of the burning velocity curve, in agreement with experimental observations. __________ Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 5, pp. 14–22, September–October, 2005.     

3种肠杆菌科细菌的耐药性变迁

目的研究大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌的耐药性变迁。方法对2007～2009年临床分离的大肠埃希菌(645株)、肺炎克雷伯菌(260株)和阴沟肠杆菌(150株),采用纸片扩散法进行体外药敏测定,并依据美国临床实验室标准化协会(Clinical and Laboratory Standards Institute,CLSI)规定的标准,分析3种肠杆菌科细菌的耐药性变迁。结果大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌对氨苄西林的耐药率均较高;对头孢他啶的耐药率低于头孢噻肟;与2007年比较,2008年和2009年对头孢吡肟的耐药率明显增长;未发现对亚胺培南耐药菌株的产生。结论细菌耐药性不断增强已成为临床治疗面临的重要难题,应从耐药监测、医院感染控制、合理使用抗生素等多方面努力,减少细菌耐药性的产生。     

Rate of propagation and of damping of ultrasound in polycaproamide fibres of elastics

Conclusions The change in propagation rate and in damping of ultrasound in elastic polycaproamide yarns has been studied. It has been found that the change in these figures is determined by the same mechanism as in yarns from the press chamber method of preparation.A region of high values of the damping coefficient (25–33) has been found for elastic yarns.Texturizing yarns by the false twist method exerts a more intense action on the polymer than the compression and bending deformation in chamber pressing.The dependence between the rate of propagation of ultrasonic waves and the damping coefficient for elastic yarns reflects the effect of molecular orientation in the polymer itself and the geometric orientation of sections of the crimp relative to the sonication direction.Translated from Khimicheskie Volokna, No. 3, pp. 46–48, May–June, 1984.     

142例新生儿溶血病血清学检测结果分析

目的对本地区142名新生儿溶血病患者进行血清学检测,评价直接抗人球蛋白试验、游离抗体试验和抗体释放试验在该病诊断中的价值。方法对2005年1月~2007年6月各医院送检的高胆红素血症新生儿血液标本进行"三项试验"。结果142名新生儿溶血病患者中,血型分布规律为:B>A>AB>O,54.22%为B型,43.66%为A型,二者差异有显著意义。直抗试验阳性率为76.76%,释放试验阳性率为100%,游离试验阳性率为50.70%。释放试验阳性的A型患者中,抗-AB检出率为47.17%,B型患者中的检出率为53.03%,二者差异无显著意义。结论释放试验敏感度最高,是判定新生儿溶血病最有力的证据,在本地区,B型新生儿可能更易患新生儿溶血病。     

Control of the Properties of Glazes by the Aid of Eutectics

Published equilibrium eutectics and other low-temperature invariant points were investigated regarding deformation temperatures and rates. Their solubility in dilute acid, alkali, and phosphate solutions was also studied, and the one showing no solubility and the lowest deformation temperature was chosen as the center of the deformation series in each of the alkali-alumina-silica systems. The KAS, LAS, and NAS deformation eutectics were assembled in a triaxial system in which fusion temperatures and rates were determined, and the deformation eutectic was thus determined. Similar data were developed on combinations of the individual alkali eutectics and the lead-alumina-silica deformation eutectic reported in Part I of this study. The deformation eutectic of the combined alkali series and the lead-alumina-silica eutectic were combined in a series and the deformation eutectic was determined.     

Estimation of the kinetics of impregnation of fibre materials

An automated method of estimating the kinetics of formation and migration of gas inclusions in fibre materials was developed. The method can be used to estimate the change in the concentration and characteristic dimensions of gas inclusions in materials during impregnation and subsequent drying and polymerization.Stekloplastik—Sertifikat Co., Moscow. Translated from Khimicheskie Volokna, No. 3, pp. 46–50, May–June, 1994.     

Chemistry of Vaporization of Refractory Materials

Most recently the practical importance of high temperature vaporization reactions has appeared in the synthesis of pure materials through vapor transport reactions and in the study of the movement of materials in nuclear power reactor experiments. The most recent basic development is the establishment, at temperature, of the range of nonstoichiometry in oxides. Long-standing applications of vaporization studies are in the measurement of thermodynamic properties and the discovery of new species. A discussion is given of the principles of physical chemistry important in vaporization studies, notably the concepts of equilibrium, phase behavior, thermodynamics, solid solution, and kinetics. The important factors influencing equilibrium vaporization phenomena are discussed and illustrated. A proper course of a vaporization study consisting of 9 stages is proposed. The important experimental techniques of Knudsen effusion, Langmuir vaporization and mass spectrometry are discussed. The principles, the factors, the course of a study and the experimental techniques and procedures are illustrated by recent work on the Ti-O system.