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排序方式: 共有1552条查询结果,搜索用时 31 毫秒
111.
环保型钻井液体系 总被引:9,自引:0,他引:9
在大量室内研究基础上,研发了环保型钻井液体系,其基础配方为:4%膨润土浆+0.3%IND-30+1.5%NAT-20+3%FXJS+2%NFT-25.该钻井液体系采用环保添加剂配制,抗温能力强,达150℃;抗污染性能佳,抗盐量可达30%,抗土侵量达8%;油层保护效果好,渗透率恢复率在81.5%以上;环保性能理想,废弃钻井液抛洒后,地表层0~20 cm厚度土壤的环境质量指标均保持在中国土壤环境质量标准二级水平以上,同时使沙地土壤的水分含量和肥力水平大大提高.该环保型钻井液体系已先后在塔里木、克拉玛依和江苏油田的15口井中获得成功应用,环保与油层保护效果理想.抛洒过废弃钻井液的井区周围土壤的有机质、速效氮、速效磷和速效钾含量明显提高.与常规钻井液相比,使用环保型钻井液体系单井平均可节约综合成本40.87×10<'4>元,15口井总计可节约综合成本613.05×10<'4>元. 相似文献
112.
Biodegradation of polyethylene via complete solubilization by the action of Pseudomonas fluorescens,biosurfactant produced by Bacillus licheniformis and anionic surfactant
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113.
Pilot scale production of extracellular thermo‐alkali stable laccase from Pseudomonas sp. S2 using agro waste and its application in organophosphorous pesticides degradation
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114.
Rafael Salles Kurusu Nicole Raymonde Demarquette Catherine Gauthier Jean‐Marc Chenal 《Polymer International》2014,63(6):1085-1093
Poly(3‐hydroxybutyrate) (PHB) undergoes an ageing process that contributes to its remarkable fragility. Blending it with an elastomer is a possibility to increase toughness. In this work, the mechanical properties of a 70/30 wt% blend of PHB and poly(ethylene‐co‐methyl‐acrylate‐co‐glycidyl‐methacrylate) were studied over time. The phenomenon of ageing affected the blend, which lost its ductility and became fragile days after its processing. Differential scanning calorimetry and small angle X‐ray scattering analyses showed that this drop in mechanical properties was due to changes in the crystalline structure of the matrix. Annealing reduced fragility, increased toughness and prevented a re‐ageing of the blend. Biodegradation in soil was also more intense for annealed samples. © 2013 Society of Chemical Industry 相似文献
115.
生物稳定聚氨酯材料研究进展 总被引:8,自引:0,他引:8
综述了聚氨酯生物材料的体内降解机理以及所谓的“生物稳定聚氨酯材料”的研究进展,并对其发展进行了展望。 相似文献
116.
Improvement of treatment efficiency of thermophilic oxic process for highly concentrated lipid wastes by nutrient supplementation 总被引:1,自引:0,他引:1
The biodegradation of highly concentrated lipid wastes was conducted by a thermophilic oxic process (TOP). In order to improve the treatment efficiency of TOP, the stimulatory effect of nutrient supplementation was examined. A model nutrient supplement that satisfied the essential components necessary to promote degradation of lipid wastes was developed. The importance of balanced nutrient supplement consisting of organic and inorganic components was demonstrated. Regardless of the source of either vegetable oil or animal fat, the combination of 1.5 g of yeast extract, 1 g of urea and 60 ml of trace-element solution was effective to stimulate the degradation of 15 g of lipids by TOP. With this combination, degradation efficiencies of 68% and 77% in a 120-h treatment were attained for salad oil and lard, respectively. The conversion ratio of degraded lipid materials to CO2 was 0.91, confirming the advantage of TOP, i.e., very low excess sludge generation. The effectiveness of the model nutrient supplement for stimulating the degradation of lipid materials by TOP was also confirmed when tested on three kinds of actual highly concentrated lipid wastes. A constant degradation efficiency of around 60% in a 120-h treatment was attained for all lipid wastes although further improvement of degradation efficiency was possible by some nutrient addition into the model supplement combination. Based on the model nutrient supplement, the essential components for stimulating oil degradation by TOP and the possible alternative materials for the model nutrient supplement were discussed. The results demonstrated the possibility of employing TOP (stimulated by nutrient supplement) as a new biological treatment strategy for highly concentrated lipid wastes. 相似文献
117.
概述了垃圾填埋场中微生物对污染物的吸收与生物化学作用,有机污染物的生物降解的基本原理及其影响因素,介绍了垃圾生物降解的四种基本动力学方程,提出了要重视我国在填埋场有机物降解机理方面的研究。 相似文献
118.
Ren Yibin Huang Jingjing Zhang Bingchun Yang Ke 《Frontiers of Materials Science in China》2007,1(4):401-404
Magnesium alloys are potential to be developed as a new type of biodegradable implant material by use of their active corrosion
behavior. Both in vitro and in vivo biodegradation properties of an AZ31B magnesium alloy were investigated in this work. The results showed that AZ31B alloy
has a proper degradation rate and much lower hydrogen release in Hank’s solution, with a degradation rate of about 0.3 mm/year
and hydrogen release below 0.15 mL/cm2. The animal implantation test showed that the AZ31B alloy could slowly biodegrade in femur of the rabbit and form calcium
phosphate around the alloy sample, with the Ca/P ratio close to the natural bone. 相似文献
119.
采用微生物菌株和从该菌株提取的粗酶液对己内酰胺进行降解,并对己内酰胺的降解动力学进行了研究.结果表明,初始己内酰胺的浓度越小,降解速率常数越大,半寿期越短,微生物的降解能力越强;由微生物提取的粗酶液(胞外酶)的Km值较小,对己内酰胺有较强的亲和力,可有效地降解己内酰胺。 相似文献
120.
Z. F. Yang X. H. Xia G. H. Huang J. S. Zhou X. Rong 《Petroleum Science and Technology》2008,26(7):868-886
Biodegradation of petroleum contaminants in natural water was studied within an Asian river context where high-suspended sediment content exists. Petroleum contaminant is one of the main pollutants in the Yellow River; at the same time, there is a high sediment content in the river system. This research highlighted the effect of sediment on the biodegradation of petroleum contaminants, as well as the related mechanisms regarding the effect. Biodegradation of petroleum contaminants was studied under different sediment contents. The distribution of petroleum contaminants in water and sediment phases as well as the relevant biodegradation kinetics were also investigated. The results showed that in water system with the sediment content of 0.5 g/L, about 84% of petroleum contaminants with the initial concentration of 11.64 mg/L could be degraded after incubation for 63 days at 20°C. It was also indicated that the presence of sediment exerted significant influences on the biodegradation of petroleum contaminants in water system, and the influences were different from one cultivation stage to another. In the first stage, the biodegradation rate was higher in the water system with sediment than in that without sediment. In the second stage, the biodegradation rate was lower in the former than in the latter. In the last stage, the biodegradation rate was higher in the water system with sediment than in that without sediment. The presence of sediment could stimulate the growth of petroleum contaminant-degrading bacteria. Moreover, about 90% of the contaminants and bacteria were attached on the sediment. The sorbed contaminants on sediment could also be biodegraded by bacteria. The biodegradation of contaminants in water and sediment phases all fit well with the first-order kinetics, and the biodegradation rate constant in water phase was higher than that in sediment phase. However, as the contaminant concentration at the sediment phase was much higher than that in water phase, the biodegradation of petroleum contaminants mainly occurred at the sediment phase. 相似文献