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991.
992.
纳米二氧化钛的杀菌性能测试 总被引:9,自引:0,他引:9
采用新工艺制备出具有光催化性的纳米二氧化钛。为了验证其杀菌性,以工业循环冷却水中的异养菌为实验对象进行杀菌实验,结果表明:自制纳米二氧化钛具有良好的杀菌性,杀菌率可达99.2%,而且可以回收,循环使用,产品有广阔的应用前景。 相似文献
993.
Model compound studies were carried out to elucidate the reaction mechanisms taking place during the liquefaction of coal with the hydrogen produced from the reaction of zinc and water. In compounds of the type Ph-(CH2)n-Ph the splitting of the aliphatic bridge was easier with higher n values. Ether type compounds such as diphenylether were unreactive although the C-O bond in dibenzylether was easily cleaved. Condensed ring aromatic compounds gave low conversion with hydrogenation being facilitated by an increase in ring number. Phenolic compounds such as phenol did not react well, but the reactivity increased with increase in aromatic ring size. The cleavage of the aliphatic bridge was accelerated by the OH group, for example, in the case of 4-hydroxydiphenylmethane bond scission was about 15 times higher than that of diphenylmethane. Heterocyclic compounds were unreactive. 相似文献
994.
Assessing the sustainability of non-renewable brackish groundwater in feeding an RO desalination plant in Bahrain 总被引:1,自引:0,他引:1
Waleed K. Al-Zubari 《Desalination》2003,159(3):211-224
The Rus-Umm Er Radhuma aquifer in Bahrain is a non-renewable source of brackish water (8-15 g/L), which forms a lens underlain everywhere with brines of over 100 g/L. Aquifer utilization has started in 1984 to feed a reverse osmosis (RO) desalination plant, with an economic life of 25 years (2010). Future plant upgrade strategy is formulated around boosting the plant production, which will require increasing the we llfield abstraction, in addition to a possible future rehabilitation program to extend the plant life by another 15 years (2025). The limiting factor in expanding the RO plant and its rehabilitation is the future feed water salinity, which have to be assessed before any investments are made to expand the RO plant and commission additional abstraction wells and implement the rehabilitation program. The aquifer management is based on mining a one-time brackish water reserve stored in the aquifer, the main management objective is stated as to sustain the aquifer future availability in feeding the desalination plant with a specified salinity limit of 20 g/L over the economic life of the plant of 25 years (1985-2010), and also over the plant extension period by rehabilitation (2010-2025). The stochastic analysis methodology utilizing conditional simulation is applied to conduct a risk assessment of violating these two pre-specified sustainability constraints under the proposed abstraction increase; and provided a tool to aid the decision-making process in the development and management of the aquifer under large uncertainties. Simulation results indicated that the risk of having the salinity of the wellfi eld produced water to increase due to the proposed increase in the wellfield abstraction to reach 20 g/L over the economic life of the plant (2010) is very small and minimal. However, it is questionable that the feed water salinity will be maintained under the proposed rehabilitation program to extend the plant economic life by another 15 years (2011-2025). For this option, it is recommended that model post-auditing be performed, and new updated predictions should be made as more data of potentiometry. salinity. and hydraulic parameters become available. 相似文献
995.
本文阐述了在循环经济理论指导下,依靠科技进步自主创新改革氧化工艺,开创了治理DSD酸氧化废水的新路:源头上减少资源的投入,实现″减量化″;末端采用资源化处理技术,回收废水中有用的资源,实现″再利用″、″再循环″。成功的解决了曾经困扰DSD酸行业发展的老大难问题,促进了我国DSD酸工业的发展,从DSD酸生产和出口大国正发展成为强国。 相似文献
996.
Fatigue crack propagation (FCP) tests were conducted at various frequencies on nylon-6,6 specimens equilibrated over a range of moisture levels to determine the crack growth rates and the crack-tip temperatures as a function of water content. Frequency-sensitivity was correlated with the amount of crack-tip heating taking place, with crack-tip temperature being found to depend strongly on the estimated loss compliance, D″, of the material. The frequency-sensitivity of FCP in nylon was seen also to be affected by mean stress, suggesting that creep processes are often significant in FCP of nylon. 相似文献
998.
Removal of chromium (VI) from dilute aqueous solutions by activated carbon developed from Terminalia arjuna nuts activated with zinc chloride 总被引:1,自引:0,他引:1
Different structured activated carbons were prepared from Terminalia arjuna nuts, an agricultural waste, by chemical activation with zinc chloride for the adsorption of Cr(VI) from dilute aqueous solutions. The most important parameter in chemical activation was found to be the chemical ratio (activating agent/precursor, g/g). Carbonization temperature and time are the other two important variables, which had significant effect on the pore structure of carbon. A high surface area of was obtained at a chemical ratio of 300%, carbonization time and temperature of 1 h and 500 °C, respectively. The activated carbon developed shows substantial capability to adsorb Cr(VI) from dilute aqueous solutions. The parameters studied include pH, adsorbent dosage, contact time, and initial concentrations. The kinetic data were best fitted to the Lagergren pseudo-first-order model. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. The maximum removal of chromium was obtained at pH 1.0 (about 99% for adsorbent dose of 2 g/l and 10 mg/l initial concentration). 相似文献
999.
1000.
本文通过分析传统水浴提取紫甘蓝红色素的传质机理,建立了提取过程中紫甘蓝红色素得率与各工艺条件的动力学模型。经验证,所建立的动力学理论模型与实测数据相吻合,可良好地模拟色素提取过程,用于指导工业生产。 相似文献