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991.
回收PTA废料生产增塑剂 总被引:3,自引:0,他引:3
介绍了扬子石化公司PTA生产过程中所排各种废料的分离提纯及回收利用,对难以回收的氧化残渣的分离回收和利用作了重点论述。提供了用所回收的TA和混合苯二甲本乡生产剂的工艺流程和工艺参数。 相似文献
992.
采用高压水和喷嘴的引射原理,使水射流通过喷嘴后高效雾化,达到降尘的目的,并主要沉降5μm以下对人体具有致命危害的呼吸性粉尘。当更换喷嘴后也可进行积上和物体的表面清洗。 相似文献
993.
本文用CN算法研究了我国近期大陆东部和西部南北带及邻近区域共23次强震前的TIP,即强震发生概率增长时间。结果表明,18次强震发生在被判定的强震发生概率增长时间的TIP内。TIP警戒约占总研究时空域的30%,获得了较好的中期地震预测效果。表明CN算法可作为强震中期预测的手段之一。 相似文献
994.
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996.
The concern of this paper is with the spatial consequences of development in a given rural setting and the way in which physical planning fits into the revival of a dying rural area, particularly in Third World Countries. It is based on experience derived from Dekinal in Benue State, Nigeria and endeavours to define a rural area by briefly discussing its characteristics and highlighting its problems. It proposes a comprehensive development planning process to induce development based on available resources. 相似文献
997.
998.
The kinetics, reaction pathways and product distribution of oxidation of tetrachloroethylene (PCE) by potassium permanganate (KMnO4) were studied in phosphate-buffered solutions under constant pH, isothermal, completely mixed and zero headspace conditions. Experimental results indicate that the reaction is first-order with respect to both PCE and KMnO4 and has an activation energy of 9.3+/-0.9 kcal/mol. The second-order rate constant at 20 degrees C is 0.035+/-0.004 M(-1) s(-1), and is independent of pH and ionic strength (I) over a range of pH 3-10 and I approximately 0-0.2 M, respectively. The PCE-KMnO4 reaction may proceed through further oxidation and/or hydrolysis reaction pathways, greatly influenced by the acidity of the solution, to yield CO2(g), oxalic acid, formic acid and glycolic acid. Under acidic conditions (e.g., pH 3), the further oxidation pathway will dominate and PCE tends to be directly mineralized into CO2 and chloride. Under neutral (e.g., pH 7) and alkaline conditions (e.g., pH 10), the hydroxylation pathway dominates the reaction and PCE is primarily transformed into oxalic acid prior to complete PCE mineralization. Moreover, all chlorine atoms in PCE are rapidly liberated during the reaction and the rate of chloride production is very close to the rate of PCE degradation. 相似文献
999.
Advancement of renewables in Bangladesh and Thailand: Policy intervention and institutional settings
This article reviews and analyses the advancement of renewable sources of energy in Bangladesh and Thailand in terms of policy intervention and institutional settings. Since renewable forms of energy emit far smaller amounts of greenhouse gas compared with fossil fuels, their use should mitigate climate change impacts while contributing to the provision of energy services. The article turns first to a review of energy–environment trends and the potential for renewables in these two nations. It then discusses strategies for the advancement of renewables. It is argued that further significant efforts can be made towards the advancement of renewables in Bangladesh and Thailand. These two nations could also learn from the experience in industrialized nations and other developing nations with regard to requisite policy instruments and processes. A number of barriers remain to the advancement of renewables, especially in terms of policy arrangements, institutional settings, financing mechanisms and technologies. Resources, cooperation and learning are required in order to overcome such barriers and to foster the development of necessary policy measures. Implementation of the clean development mechanism (CDM) under the Kyoto Protocol, and replication and adaptation of effective strategies from other settings are possible avenues for this. 相似文献
1000.
Chao‐Hsien Liaw Yao‐Lung Tsai Mow‐Soung Cheng 《Journal of the American Water Resources Association》2006,42(2):311-322
The Keelung River Basin in northern Taiwan lies immediately upstream of the Taipei metropolitan area. The Shijr area is in the lower basin and is subject to frequent flooding. This work applies micromanagement and source control, including widely distributed infiltration and detention/ retention runoff retarding measures, in the Wudu watershed above Shijr. A method is also developed that combines a genetic algorithm and a rainfall runoff model to optimize the spatial distribution of runoff retarding facilities. Downstream of Wudu in the Shijr area, five dredging schemes are considered. If 10‐year flood flows cannot be confined in the channel, then a levee embankment that corresponds to the respective runoff retarding scheme will be required. The minimum total cost is considered in the rule to select from the regional flood mitigation alternatives. The results of this study reveal that runoff retarding facilities installed in the upper and middle parts of the watershed are most effective in reducing the flood peak. Moreover, as the cost of acquiring land for the levee embankment increases, installing runoff retarding measures in the upper portion of the watershed becomes more economical. 相似文献