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131.
针对钢框架结构形式的电力配电房在基本荷载组合工况下构件承载能力的关键问题,运用ABAQUS有限元分析软件对模型进行空间静力分析,得出电力配电房在各种工况下的最不利荷载及其位置;针对电力配电房在火灾工况下构件耐火性能的关键问题,运用ABAQUS模拟分析其在火灾工况下的温度场分布和钢框架结构的承载能力和力学性能,并对这两类工况对比分析。研究结果表明:在基本荷载工况下,电力配电房在恒荷载与活荷载形成的组合效应下产生的沿X、Y、Z方向的剪力和弯矩最大,且其形成的竖向位移也最大;在火灾工况下,电力配电房最大应力位置与普通荷载工况大致相同,但最大位移位置不同;虽有局部钢材应力超限,但钢框架结构仍具备承载能力,设计人员可将应力超限的构件替换为屈服强度更高的钢材而非全部替换,既保证了整体结构的安全性,又达到节约材料降低造价的目的。  相似文献   
132.
高氟饮用水脱氟技术   总被引:2,自引:0,他引:2  
综合了国内目前使用的高氟饮用水脱氟技术,重点介绍两种已用于设备制作的脱氟技术--活性氧化铝和活化沸石。目的介绍了于高氟地区。对饮用水进行脱氟,对氟的地方病进行治理。  相似文献   
133.
本文简要地介绍了QSDWZHYC—1智能辅助决策系统结构、功能以及所采用的技术途径。应用QSDWZHYC—1系统可预测企事业单位现有房屋的震害,评估经济损失和人员伤亡,优化抗震加固方案,识别高危害房屋类别,找出单位建(构)筑物地震危害的薄弱环节。为企事业单位抗震减灾对策进行辅助决策。  相似文献   
134.
• Real ML-GFW with high salinity and high organics was degraded by O3/H2O2 process. • Successful optimization of operation conditions was attained using RSM based on CCD. • Single-factor experiments in advance ensured optimal experimental conditions. • The satisfactory removal efficiency of TOC was achieved in spite of high salinity. • The initial pH plays the most significant role in the degradation of ML-GFW. The present study reports the use of the O3/H2O2 process in the pretreatment of the mother liquor of gas field wastewater (ML-GFW), obtained from the multi-effect distillation treatment of the gas field wastewater. The range of optimal operation conditions was obtained by single-factor experiments. Response surface methodology (RSM) based on the central composite design (CCD) was used for the optimization procedure. A regression model with Total organic carbon (TOC) removal efficiency as the response value was established (R2 = 0.9865). The three key factors were arranged according to their significance as: pH>H2O2 dosage>ozone flow rate. The model predicted that the best operation conditions could be obtained at a pH of 10.9, an ozone flow rate of 0.8 L/min, and H2O2 dosage of 6.2 mL. The dosing ratio of ozone was calculated to be 9.84 mg O3/mg TOC. The maximum removal efficiency predicted was 75.9%, while the measured value was 72.3%. The relative deviation was found to be in an acceptable range. The ozone utilization and free radical quenching experiments showed that the addition of H2O2 promoted the decomposition of ozone to produce hydroxyl radicals (·OH). This also improved the ozone utilization efficiency. Gas chromatography-mass spectrometry (GC-MS) analysis showed that most of the organic matters in ML-GFW were degraded, while some residuals needed further treatment. This study provided the data and the necessary technical supports for further research on the treatment of ML-GFW.  相似文献   
135.
The process chain for Carbon Capture and Sequestration (CCS) includes tubing for injection of CO2 into saline aquifers. The compressed CO2 is likely to contain specific impurities; small concentrations of SO2 and NO2 in combination with oxygen and humidity are most harmful. In addition, CO2 saturated brine is supposed to rise in the well when the injection process is interrupted. The material selection has to ensure that neither CO2 nor brine or a combination of both will leak out of the inner tubing. In this comprehensive paper the investigated materials range from low-alloy steels and 13% Cr steels up to high-alloy materials. Electrochemical tests as well as long term exposure tests were performed in CO2, in brine and combination of both; pressure was up to 100 bar, temperature up to 60 °C. Whereas the CO2 stream itself can be handled using low alloy steels, combinations of CO2 and brine require more resistant materials to control the strong tendency to pitting corrosion. The corrosion behavior of heat-treated steels depends on factors such as microstructure and carbon content. For different sections of the injection tube, appropriate materials should be used to guarantee safety and consider cost effectiveness.  相似文献   
136.
A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively.  相似文献   
137.
The fiber length and packing density of the PTFE membrane element were increased. The MBR was stably operated under an SADm of 0.13 m3·m-2·hr-1. Specific energy consumption was estimated to be less than 0.4 kWh·m-3. In this study, we modified a polytetrafluoroethylene (PTFE) hollow-fiber membrane element used for submerged membrane bioreactors (MBRs) to reduce the energy consumption during MBR processes. The high mechanical strength of the PTFE membrane made it possible to increase the effective length of the membrane fiber from 2 to 3 m. In addition, the packing density was increased by 20% by optimizing the membrane element configuration. These modifications improve the efficiency of membrane cleaning associated with aeration. The target of specific energy consumption was less than 0.4 kWh·m-3 in this study. The continuous operation of a pilot MBR treating real municipal wastewater revealed that the MBR utilizing the modified membrane element can be stably operated under a specific air demand per membrane surface area (SADm) of 0.13 m3·m-2·hr-1 when the daily-averaged membrane fluxes for the constant flow rate and flow rate fluctuating modes of operation were set to 0.6 and 0.5 m3·m-2·d-1, respectively. The specific energy consumption under these operating conditions was estimated to be less than 0.37 kWh·m-3. These results strongly suggest that operating an MBR equipped with the modified membrane element with a specific energy consumption of less than 0.4 kWh·m-3 is highly possible.  相似文献   
138.
通过对四川省6个500kV输变电工程的水土保持设施验收技术评估工作,分析比较了上述工程水土流失防治责任范围在水土保持方案报告书(可研)阶段、工程建设期以及运行期的变化情况,结果表明建设期水土流失防治责任范围面积占水土保持方案报告书的50%~70%,运行期水土流失防治责任范围面积占建设期的30%~50%。  相似文献   
139.
在水质监测及诸多行业的工业废水监测中,COD是一个必测项目,微波密封消解测定COD是一种新方法,此方法与国标(GBll914—89)重铬酸钾法回流测定COD相比,具有成本低、操作安全、快速便捷等优点,其测定结果同标准重铬酸钾回流法相比对线性相关系数r大于0.999,是值得推广使用的一种方法。但为了得到准确可靠的分析结果,提高测定COD的工作效率,必须严格把握好一些关键性的技术问题。  相似文献   
140.
The upflow anaerobic sludge blanket (UASB) process is reported to be a sustainable technology for domestic wastewaters treatment in developing countries and for small communities. However, the inability of UASB process to meet the desired disposal standards has given enough impetus for subsequent post treatment. In order to upgrade the UASB based sewage treatment plants (STPs) to achieve desired effluent quality for disposal or for reuse, various technological options are available and broadly differentiated as primary post-treatment for the removal of organic and inorganic compounds and suspended matter; secondary post-treatment for the removal of hardly degradable soluble matter, colloidal and nutrients; and polishing systems for removals of pathogens. Hence, this paper discusses the different systems for the treatment of UASB reactor effluent treating sewage. Additionally, a comparative review, an economic evaluation of some of the emerging options was conducted and based on the extensive review of different integrated combination, i.e. UASB-different aerobic systems, a treatment concept based on natural biological mineralization route recognized as an advanced technology to meet all practical aspects to make it a sustainable for environmental protection, resource preservation and recovering maximum resources.  相似文献   
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