不同熔化速率下的电渣重熔过程数值模拟分析

电渣重熔能提高钢锭的质量,从而满足特种行业的需要,其过程伴随着复杂的物理现象,存在着磁流体流动、传热和传质以及电化学等多方面的影响。通过耦合电磁以及流动和温度方程对电渣重熔过程的三维瞬态进行了数学模拟,研究了熔化速率对重熔过程的影响。结果表明：电流密度、焦耳热和电磁力都随着熔化速率的增大而增大,当熔化速率由14.4 kg/h增加到27.0kg/h,电流密度、焦耳热和电磁力最大值的增大比例超过100%。随着熔化速率的增大,温度最大值有小幅的增加,而且速度最大值的增大幅度接近50%;金属熔池深度则由27 mm增大到38 mm,不利于保证铸坯的质量。     

Reinforcement Treatment on the Uneven Subsidence of Foundation

There are several methods to cope with the common problem of the uneven subsidence of foundation. The reason for uneven settlement of foundation of the frame structure was analyzed in this paper. Considering the limitation of the construction site and the principle of consolidation, a feasible reinforcement measure was taken. Meanwhile, a practical construction pattern was chosen upon the comparison of the reinforcement technology analysis and the construction method. The observation of the settlement result after consolidation of the structure shows that the result of this reinforcement treatment pattern is effective.     

Study on Optimum Design of Rectangular Sedimentation Tanks

In this paper,the flow velocity fields,suspended solids concentration fields and flow-through curves in rectangular sedimentation tanks with different reaction baffles location,inlet horizontal velocity and length height ratio are simulated in detail using a developed mathematical model given in Reference 2.According to the numerical results,the influence of different reaction baffles location,inlet horizontal velocity and length height ratio on the operating efficiency is analyzed.Finally,the rational reaction baffles location,inlet horizontal velocity and length height ratio are presented.     

Feasibility for Building the Under-ground Sewage Treatment Plant in Chongqing City

With the development of the economy, the demand forhabitation is enhanced and the sewage and industrial waster water must be disposed before outlet. Today, most of the sewage treatment plants are built on the aboveground without discussing the underground. Therefore, by the comparative analysis of the property and cost of the underground sewage treatment plant and the ground, the underground sewage treatment plant have merits in save the city land and improvement environment.The Chongqing citypossess a lot of advantages in using the space of underground with the analysis of the physiognomy and geology condition of the Chongqing city. Therefore, the development of underground sewage treatment plant is feasible in the Chongqing city.     

Load dynamic matching of supply and demand side based on the utilization of urban sewage heat energy

Flowing dynamic characteristics and its temperature dynamic characteristics of a three-level sewage pipe network in Chongqing were analyzed. A mall's building whole year load was simulated. In the adverse condition of wastewater flow, the market construction peak discharge heat was compared with the sewage heat load, the balance between the most adverse flow and the building demand was found. Explored supply and demand matching method between urban sewage and city building load in flow adverse condition to take full advantage of the urban sewage cold and hot resources. the composite system was adeptcd to make up the most unfavorable flow time of sewage average heat load and the construction load difference; it also puts forward principle of load sharing and control strategy aimed at compound system.     

Design of Distributed Monitoring System of Wastewater Treatment Process

Based on introducing fieldbus and fieldbus control system, in this paper, a distributed monitoring system for city wastewater treatment network based on LonWorks is given, the construction, function and character of this network are analyzed.     

光皮桦超干种子回湿方法研究

超干处理的光皮桦种子直接吸胀会引起种子活力下降,回湿处理可以减轻吸胀过程所造成的损伤.本试验以超干储藏1年的光皮桦种子,分别经回湿处理中湿度、温度和时间三因素组合的30种预先回湿处理.结果表明：湿度、温度和时间三因素是回湿处理的主要因素;30种处理中有6种处理的发芽率、发芽指数和高于对照,以30℃60%RH回湿4 d显著高于对照,效果最佳.     

硝酸钙在底泥修复中的作用机理及

受污染底泥的修复已经成为水环境修复中的重要组成部分，在底泥中注入硝酸钙则是近十多年来发展起来的一种污染底泥原位处理技术。全面分析了硝酸钙在底泥修复中去除有机物、抑制磷的释放以及消除水体黑臭现象的机理，并介绍了这一技术在国内外的研究和应用状况。研究成果表明：在底泥中注入硝酸钙的技术已从实验室和中试研究阶段发展到了实际的工程动作阶段，并且在有机物PAHS的降解和硫化物的去除方面已经得到了很好的效果。     

低温和近中温猪粪液厌氧处理的装置比较研究

作了ＵＢＦ、ＵＡＳＢ和厌氧上折流反应器处理猪粪过筛液运行性能的实验室比较。结果表明：它们的运行指标基本一致。综合比较，ＵＢＦ略优于ＵＡＳＢ，ＵＡＳＢ略优于上折流反应器。在发酵温度１０℃段，负荷１．９～２．３ｇＣＯＤ／（Ｌ·ｄ），装置产气率平均０．３２～０．５１Ｌ／（Ｌ·ｄ），ＣＯＤ平均去除率８２．２％～９１．０％；１５℃段，负荷２．５～２．６ｇＣＯＤ／（Ｌ·ｄ），装置产气率０．５７～０．５９Ｌ／（Ｌ·ｄ）；２５℃段，负荷５．５～５．７ｇＣＯＤ／（Ｌ·ｄ），装置产气率１．９３～２．０１Ｌ／（Ｌ·ｄ）。