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561.
562.
光纤传输在地震台信号传输中的应用 总被引:1,自引:0,他引:1
深圳地震台处于强雷电干扰地区,雷电干扰的破坏给深圳地震台的各类设备带来严重的损害,造成较大的经济损失,后来在信号传输线路上改用了光纤传输,起到了明显的效果。作者将深圳台在应用光纤传输地震信号的实践工作进行简要总结,供一线台站的同行参考。 相似文献
563.
采用陶瓷微滤膜膜组件回收钛白粉厂锻烧尾气洗涤废水中的钛白粒子,在采用压缩空气反冲洗的措施下,对影响膜通量的因素包括尾气洗涤废水的性质(TiO2浓度、温度)、膜孔径、操作压力等进行了探讨,并进行了长期稳定性的考察。结果表明,采用陶瓷微滤膜回收钛白粉厂锻炼尾气洗涤废水中的TiO2是可行的,TiO2截留率可达99%以上;试验确定了对可工业化应用的工艺操作参数,为工艺的工业化应用奠定了基础。 相似文献
564.
Wies?aw W Su?kowski Justyna Polak Iwona Miszta? Jaros?aw Miszta? Mariola Bartoszek Anna Su?kowska 《Water environment research》2006,78(11):2186-2192
The aim of the present work was to compare the concentration changes of polyaromatic hydrocarbons (PAH) and the course of humification processes during wastewater treatment. Studies of samples from a biological-mechanical wastewater treatment plant in Sosnowiec-Zagórze (Poland) were carried out. Determination of PAH was performed both for wastewater sludge and sludge water. Observations of the course of humification processes for humic acid fractions isolated from sludges were conducted. Analysis of PAH extracted from wastewaters and from sludge was performed by means of high-performance liquid chromatography. Investigations of humification processes were conducted by electron paramagnetic resonance and nuclear magnetic resonance methods. The elementary composition changes in the structure of the extracted humic acids were determined. It was found that polyaromatic hydrocarbons appear during the processes of humification. Their content in water decreased only after the process of sludge aeration; however, sludge water leaving the settlers was PAH-enriched. 相似文献
565.
土壤毛管渗滤系统在浙江湖州某区新农村示范工程中的应用 总被引:1,自引:0,他引:1
针对浙江湖州某区生活污水的特点,分析了国内外生活污水处理的各种常规工艺,以采用先进的土壤毛管渗滤处理技术为主,结合能耗很低的微动力生化预处理和人工生态塘处理技术,取得了良好的处理效果。并详细介绍了土壤毛管渗滤处理系统的组成、各个处理单元的设计参数,分析总结了设计工艺的特点。 相似文献
566.
Role of amination of a polymeric adsorbent on phenol adsorption from aqueous solution 总被引:7,自引:0,他引:7
Adsorption of seven phenols, one aromatic carboxylic acid and one sulfonated aromatic acid from aqueous solution, by a hypercrosslinked polymeric adsorbent (CHA-111) and the derivative animated by dimethylamine was compared. The results of different adsorption isotherms indicated that amino group on the polymeric matrix played a significant role on adsorption of almost all the employed compounds. For most employed compounds adsorption capacities increase to different degree and significantly for those with lower value of pK(a). It may be attributed to the enhanced adsorbent-adsorbate interaction for amino group introduced on the polymeric matrix. The empirical Freundlich isotherm equation was employed to interpret the adsorbent-adsorbate interaction. The adsorption enthalpy change indicated the uptake of phenols on MCH-111 to be an enhanced physical adsorption because of the hydrogen-bonding interaction. Adsorption kinetic study of phenols on CHA-111 and MCH-111 was also conducted and amino group on the matrix will reduce the adsorption rate for change of pore size distribution and loss of macroprous volume as well as the hydration effect on the surface partly. 相似文献
567.
568.
The capacity factors of a series of hydrophobic organic compounds (HOCs) were measured in soil leaching column chromatography (SLCC) on a soil column, and in reversed-phase liquid chromatography on a C18 column with different volumetric fractions (phi) of methanol in methanol-water mixtures. A general equation of linear solvation energy relationships, log(XYZ) XYZ0 + mV(I)/100 + spi + bbetam + aalpham, was applied to analyze capacity factors (k'), soil organic partition coefficients (Koc) and octanol-water partition coefficients (P). The analyses exhibited high accuracy. The chief solute factors that control logKoc, log P, and logk' (on soil and on C18) are the solute size (V(I)/100) and hydrogen-bond basicity (betam). Less important solute factors are the dipolarity/polarizability (pi*) and hydrogen-bond acidity (alpham). Log k' on soil and log Koc have similar signs in four fitting coefficients (m, s, b and a) and similar ratios (m:s:b:a), while log k' on C18 and logP have similar signs in coefficients (m, s, b and a) and similar ratios (m:s:b:a). Consequently, logk' values on C18 have good correlations with logP (r > 0.97), while logk' values on soil have good correlations with logKoc (r > 0.98). Two Koc estimation methods were developed, one through solute solvatochromic parameters, and the other through correlations with k' on soil. For HOCs, a linear relationship between logarithmic capacity factor and methanol composition in methanol-water mixtures could also be derived in SLCC. 相似文献
569.
This work establishes methods of reducing the amount of methane produced from the anaerobic treatment of piggery wastewater by either reducing the storage time before solid/liquid separation or inhibiting the activity of methanogens in anaerobic wastewater treatment system. Experimental results showed these two methods can be adopted effectively to reduce methane production resulting from anaerobic piggery wastewater treatment. First, the wastewater must be processed using solid/liquid separation immediately after washing pig houses. This process can reduce by 62% the biogas production and indirectly decrease the methane production from the anaerobic wastewater treatment reactor. Second, adding 10 mg L(-1) bromochloromethane (BCM) daily into the anaerobic wastewater treatment reactor can significantly reduce the amount of biogas and methane produced during the anaerobic fermentation process. Furthermore, biogas production can be completely inhibited after 4 days. Adding BCM (< or =10 mg L(-1)) to wastewater only slightly affected the efficiency of the anaerobic wastewater treatment process. Results in this study can provide the basis for further research on reduction of the amount of methane produced from anaerobic wastewater treatments. 相似文献
570.
交联菌丝体吸附剂的制备及其对Cr3+的吸附特性 总被引:1,自引:0,他引:1
深入研究了交联菌丝体吸附剂的制备工艺及其对Cr3+的吸附特性.交联菌丝体吸附剂制备工艺简单,但在制备过程中,活化剂NaOH和交联剂的用量对吸附特性影响较大.与纯菌丝体吸附剂相比,交联菌丝体吸附剂表观吸附容量提高48%,达到49.83 mg/g(pH=2.53,水溶液中的Cr3+浓度为600mg/L),同时其机械强度明显增强.交联菌丝体吸附剂对Cr3+的吸附特点是将沉淀法与吸附法相结合,将沉淀与吸附两过程合二为一,从而简化了处理工艺,降低了处理成本. 相似文献