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801.
聚丙烯酸钾与腐植酸复合高吸水性树脂的合成研究 总被引:1,自引:0,他引:1
以腐植酸与丙烯酸聚合制备了高吸水性树脂,讨论了交联剂、引发剂以及KOH用量对聚丙烯酸与腐植酸高吸水性树脂吸水率的影响,结果显示在n(MBA)∶n(AA)=0.0005、n(KPS)∶n(AA)=0.0075、n(KOH)∶n(AA)约为0.70、温度为80℃的条件下合成时,其吸水倍率可达到最优值。而且在接近自然条件下(35℃)失水速度慢,保水时间可达100 h以上,重复吸水性能好。运用红外光谱分析了腐植酸与丙烯酸的反应机理。 相似文献
802.
前大油田注水系统防腐防垢技术的研究 总被引:1,自引:0,他引:1
前大油田注水系统腐蚀、结垢问题十分突出,开发了适用于前大油田注水水质的JYSJ-Q型杀菌剂、JYHZJ-Q型缓蚀阻垢剂,并通过试验确定了配套加药工艺.经现场应用,有效缓解了注水系统的腐蚀结垢问题,获得了显著的社会效益及经济效益. 相似文献
803.
In the in situ leaching (ISL) method, pore water ionic content is determined in small cavities drilled in mortar/concrete specimens. Prior investigations have demonstrated the ISL applicability to obtain pH and nitrite ion concentration in concrete/mortar pore water. The application of the method is extended here to determine pore water chloride ion concentration (and pH) within practical test times in mortars and concretes prepared in the laboratory and in concrete cores extracted from a bridge deck in deicing salt service. Spatial resolution for the determination of composition profiles is also illustrated. Modeling of the ISL process indicates that chloride binding accelerates the approach toward a terminal cavity concentration, reducing test duration to practical lengths for moderate permeability concretes. This acceleration can be attributed to maintaining a higher gradient of free chloride near the cavity wall due to the release, during leaching, of previously bound chloride. Consequently, there is a faster chloride buildup in the cavity water compared with the no-binding case. Experimental chloride and pH results obtained by the ISL test in mortar samples show good agreement with those from the pore water expression (PWE) method. Also, examples are presented of application of ISL data to obtain chloride binding isotherms, and pore water chloride to hydroxide ratio relevant to assessing conditions for corrosion of steel reinforcement. The ISL method presents a less costly and less disruptive alternative to PWE for pore water analysis. It is noted, however, that in a few instances ISL could not be implemented because of excessive absorption of cavity water by the surrounding medium. 相似文献
804.
含氮氧化物(NOx)废气的处理方法 总被引:3,自引:0,他引:3
介绍了氮氧化物废气的产生原理、处理方法,并结合某厂硝化废气处理装置改造过程的实例,对加压水吸收处理氮氧化物废气的方法做了详细介绍,同时将该法与其他处理方法进行了比较. 相似文献
805.
生物絮凝剂及其在水处理中的应用进展 总被引:7,自引:0,他引:7
介绍了微生物絮凝剂的种类、特点、絮凝机理和近几年来国内在不同废水处理中的应用情况,并对它的研究及应用前景做出展望。 相似文献
806.
Elisée Ouédraogo Leo Stroosnijder Abdoulaye Mando Lijbert Brussaard Robert Zougmoré 《Nutrient Cycling in Agroecosystems》2007,77(3):245-256
A field experiment was conducted in Gampela (Burkina Faso) in 2000 and 2001 to assess the impact of organic and mineral sources
of nutrients and combinations thereof in optimising crop production in till and no-till systems and to assess the economic
benefit of these options. The study showed that under conditions of rainfall deficiency, the use of a single organic resource
at an equivalent dose of 40 kg N ha−1 better secured crop yield than the application of an equivalent amount as urea-N, while a combination of organic resources
and fertiliser was better in increasing crop yield than the application of the same N amount in the form of urea. In a year
of rainfall deficiency, a mix of organic resources and fertiliser in both till and no-till systems increased crop water use
efficiency, with the result that the farmer was able to purchase only half of the normal quantity of N fertiliser to obtain
a higher yield that he would have done when all of the N was supplied in the form of urea. Under conditions where soil N is
deficient, an economic benefit was achieved when urea was combined with easily decomposable organic material (e.g. sheep dung);
mixing the urea at a dose of 40 kg N ha−1 with maize straw was not sufficient in alleviating the negative interaction due to the enhanced N immobilisation. The results
demonstrate that the use of N fertiliser alone was risky and that a higher yield, with the accompanying economic benefit,
was scarcely achieved under the prevailing rainfall conditions. The application of soil and water conservation measures can
contribute greatly to increasing the economic benefit of mineral, organic or combined organic and mineral-derived nutrient
application under semi-arid conditions. 相似文献
807.
808.
809.
工业污水深度处理回用技术研究 总被引:2,自引:0,他引:2
通过对石化企业工业污水进行曝气生物滤池、连续微滤、反渗透等深度处理,使出水满足工业化用水的水质要求,从而得以回用。 相似文献
810.
采用双螺杆挤出机通过熔融共混制备了尼龙6/(苯乙烯/丙烯腈/顺丁烯二酸酐)共聚物/玻璃纤维(PA6/SANMAH/GF)复合材料,测试了材料的拉伸强度、弯曲强度、弯曲弹性模量、缺口冲击强度、热变形温度、吸水率、熔点和熔融焓,并与GF增强PA6(PA6/GF)复合材料和GF增强PA6/(苯乙烯/丙烯腈)共聚物(PA6/SAN/GF)复合材料进行了性能对比。结果表明,在PA6与SANMAH的质量比为100:3—30时,PA6/SANMAH/GF复合材料的拉伸强度与PA6/GF复合材料相当,但高于PA6/SAN/GF复合材料,弯曲强度和弯曲弹性模量高于PA6/GF和PA6/SAN/GF复合材料.缺口冲击强度高于PA6/GF复合材料,但低于PA6/SAN/GF复合材料;在PA6与SANMAH的质量比为100:40时,PA6/SANMAH/GF复合材料的拉伸强度、弯曲强度和缺口冲击强度明显降低;在整个试验范围内,PA6/SANMAH/GF复合材料的热变形温度比PA6/GF和PA6/SAN/GF复合材料低4~7℃;吸水率随着SAN-MAH用量的增加而逐渐减小。 相似文献