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81.
垃圾堆肥高效纤维素分解菌的筛选与培育技术   总被引:2,自引:0,他引:2  
从堆肥、马粪、果园土、污泥等20个样品中,分离筛选出3株对滤纸分解旺盛的纤维素分解菌:C1、C2、C3,并外购康氏木霉、白腐菌、变色栓菌一起作为出发株,经紫外诱变处理后,在含葡萄糖的产酶培养基平板上筛选到能形成较大透明圈的突变株,并进行CMC酶活、微晶纤维素酶活及天然粗纤维分解能力测定。实验结果证明白腐菌经紫外线照射60s诱变而得的C16不仅透明圈大,CMC酶活高(60.08U/mL)是出发株的2倍,而且其对天然粗纤维分解能力强,10d分解率达35%。  相似文献   
82.
杨鸿亮 《云南环境科学》2000,19(1):51-51,58
本文对保山市城市垃圾物相组成及其发热量等性质进行了研究 ,对城市垃圾的有效利用和处理提供了技术支持 ,并提出了适合其特性的处理方式  相似文献   
83.
In this study, a novel nanoscale zero-valent iron (nZVI) composite material was successfully synthesized using a low-cost natural clay, “Hangjin 2# clay” (HJ clay) as the support and tested for the decolorization of the azo dye Methyl Orange (MO) in aqueous solution by nZVI particles. According to the characterization and MO decolorization experiments, the sample with 5:1 HJ clay-supported nZVI (HJ/nZVI) mass ratio (HJ-nZVI5) showed the best dispersion and reactivity and the highest MO decolorization efficiency. With the same equivalent Fe0 dosage, the HJ-nZVI1 and HJ-nZVI5 samples demonstrated a synergetic effect for the decolorization of MO: their decolorization efficiencies were much higher than that achieved by physical mixing of HJ clay and nZVIs, or the sum of HJ clay and nZVIs alone. The synergetic effect was primarily due to the improved dispersion and more effective utilization of the nZVI particles on/in the composite materials. Higher decolorization efficiency of MO was obtained at larger HJ-nZVI dosage, higher temperature and under N2 atmosphere, while the MO initial concentration and pH were negatively correlated to the efficiency. HJ clay not only works as a carrier for nZVI nanoparticles, but also contributes to the decolorization through an “adsorption-enhanced reduction” mechanism. The high efficiency of HJ-nZVI for decontamination gives it great potential for use in a variety of remediation applications.  相似文献   
84.
文章应用GIS软件及DRASTIC模型,选取黑龙江省某地级市进行了地下水污染现状评估、地下水污染荷载评估、地下水脆弱性评估、地下水功能价值评估及地下水污染风险防控分区.结果得出,地下水污染风险最高处位于研究区污染荷载较高的西北和西南部;中部和北部、南部的部分区域为中风险区域;其它为一般风险控制区域.研究成果为当地政府提出地下水污染防治对策和措施提供了理论依据.  相似文献   
85.
典型案例地下水污染模拟预测评估   总被引:1,自引:0,他引:1  
针对典型案例地下水污染模拟预测评估,可以选取中国东北部某典型工业污染源,应用地下水有限差分软件Visual Modflow,在地下水水均衡计算的基础上,结合气象、地质、水文、水质等资料,建立了典型工业污染源地下水水流水质预测模型.研究了地下水运动规律及水中污染物迁移转化规律,预测出未来两年内的地下水流及水质变化情况,为当地政府提出地下水污染防治对策和措施提供了理论依据.这样可以利用中国东北部某典型工业污染源,为地下水的保护提供保障.  相似文献   
86.
Journal of Material Cycles and Waste Management - Coal gangue, an industrial solid waste discarded from coal mining and processing, was used as the sole raw material to prepare brick. The coal...  相似文献   
87.
The mineral elements present in brown rice play an important physiological role in global human health. We investigated genotypic variation of eight of these elements (P, K, Ca, Mg, Fe, Zn, Cu, and Mn) in 11 different grades of brown rice on the basis of the number and distance coefficients of 282 alleles for 20 simple sequence repeat (SSR) markers. Six-hundred and twenty-eight landraces from the same field in Yunnan Province, one of the largest centers of genetic diversity of rice (Oryza sativa L.) in the world, formed our core collection. The mean concentrations (mg kg−1) of the eight elements in brown rice for these landraces were P (3,480) > K (2,540) > Mg (1,480) > Ca (157) > Zn (32.8) > Fe (32.0) > Cu (13.6) > Mn (13.2). Mean P concentrations in brown rice were 6.56 times total soil P, so the grains are important in tissue storage of P, but total soil K is 7.82 times mean K concentrations in brown rice. The concentrations of the eight elements in some grades of brown rice, on the basis of the number and distance coefficients of alleles for 20 SSR markers for the landraces, were significantly different (P < 0.05), and further understanding of the relationship between mineral elements and gene diversity is needed. There was large variation in element concentrations in brown rice, ranging from 2,160 to 5,500 mg P kg−1, from 1,130 to 3,830 mg K kg−1, from 61.8 to 488 mg Ca kg−1, from 864 to 2,020 mg Mg kg−1, from 0.40 to 147 mg Fe kg−1, from 15.1 to 124 mg Zn kg−1, from 0.10 to 59.1 mg Cu kg−1, and from 6.7 to 26.6 mg Mn kg−1. Therefore, germplasm evaluations for Ca, Fe, and Zn concentrations in rice grains have detected up to sevenfold genotypic differences, suggesting that selection for high levels of Ca, Fe, and Zn in breeding for mass production is a feasible approach. Increasing the concentrations of Ca, Fe, and Zn in rice grains will help alleviate chronic Ca, Zn, and Fe deficiencies in many areas of the world.  相似文献   
88.
This paper reviews the usage and emissions of endosulfan, the newest member of the persistent organic pollutants (POPs), in China, and its fate and behavior in Chinese environment. Endosulfan usage in China has been estimated to be approximately 25700 t between 1994 and 2004. Concentrations of endosulfan in different environmental compartments in China, such as air, soil, water, and biota, but focusing at air and surface soil, have been summarized. Concentrations of total endosulfan in surface soil across China were ranged from below detection limit (BDL) to 19000 pg·g?1 dry weight (dw), with geometric mean of 120 pg·g?1dw. The results indicated that endosulfan sulfate had highest concentration in Chinese soil, followed by ??- and ??-endosulfan. Air concentrations of endosulfan in China were ranged 0?C340 pg·m?3 for ??-endosulfan and 0?C121 pg·m?3 for ??-endosulfan, with high concentrations occurred in the cotton production areas. Gridded usage inventories of endosulfan on a fine gridded system with a 1/4° longitude by 1/6° latitude resolution were compiled, from which, emission to air and residues in soil of endosulfan were calculated in each grid by using a modified simplified gridded pesticide emission and residue model (SGPERM), an integrated modeling system combining mathematical model, database management system, and geographic information system. Total emissions were around 10800 t from 1994 to 2004. Based on the emission and residue inventories, concentrations of ??- and ??-endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell, which are in general consistent with the published monitoring data.  相似文献   
89.
介绍了常州焦化厂酚氰废水的来源、水量及实质,采用A/O生物膜处理生产工艺流程,指出目前生产过程中存在的问题及经验教训。  相似文献   
90.
草甘膦是全球范围内生产与使用量最大的除草剂。虽然草甘膦制剂被分于低毒等级,但是许多研究显示其对动物的生理、行为表达具有广泛的干扰作用。本研究将中华鳖胚胎暴露于不同浓度的草甘膦铵盐溶液以评估草甘膦除草剂对其胚胎发育及孵出幼体表型及生理表现的影响。结果显示:一定浓度范围(5~5 000 mg·L~(-1))内,草甘膦铵盐对中华鳖胚胎发育速率、孵出幼体大小、游泳能力、肝脏甘油三酯含量、超氧化物歧化酶活性、丙二醛含量以及热激蛋白70 mRNA相对表达量无显著影响。结果表明:一定浓度范围草甘膦除草剂暴露对中华鳖胚胎发育的影响较小,不改变孵出幼体的表型及其生理表现。  相似文献   
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