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91.
碱矿渣水泥基铬渣固化体的性能研究   总被引:11,自引:0,他引:11  
使用碱矿渣水泥基材料对含铬废渣进行了固化研究,并力图使固化体能够用作建材制品。结果表明,用碱矿渣水泥基材固化铬渣是可行的,固化体抗压强度达到了50MPa以上,且具有良好的抗渗性能和较低的六价铬离子浸出率,能够用作建筑材料。  相似文献   
92.
对筛选的自生固氮菌和纤维素分解菌进行混合培养,研究了菌数与菌液含氮量的变化情况.初步探索了在两种菌混合作用下对生活垃圾的分解作用及增肥效应的影响。实验证明:两种菌在一定情况下能相互利用、相互依存,经混合培养后发酵液的含氮量增高,菌数增加。在两种菌液混合作用下可以加速生活垃圾的降解,同时提高其含氮量,且含有大量的具有生物活性的固氮菌和纤维素分解菌,可作为生物活性有机肥料。  相似文献   
93.
With increasing emission of silver nanoparticles (AgNPs) into the environment, it is important to understand the effects of ambient concentration of AgNPs. The biological effects of AgNPs on Scenedesmus obliquus, a ubiquitous freshwater microalgae, was evaluated. AgNPs exerted a minor inhibitory effect at low doses. Non-targeted metabolomic studies were conducted to understand and analyze the effect of AgNPs on algal cells from a molecular perspective. During the 48?hr of exposure to AgNPs, 30 metabolites were identified, of which nine had significant changes compared to the control group. These include d-galactose, sucrose, and d-fructose. These carbohydrates are involved in the synthesis and repair of cell walls. Glycine, an important constituent amino acid of glutathione, increased with AgNP exposure concentration increasing, likely to counteract an increased intracellular oxidative stress. These results provide a new understanding of the toxicity effects and mechanism of AgNPs. These metabolites could be useful biomarkers for future research, employed in the early detection of environmental risk from AgNPs.  相似文献   
94.
微生物法烟气脱硫技术研究   总被引:34,自引:0,他引:34  
采用微生物(氧化亚铁硫杆菌,简称TF菌)法脱除烟气中的二氧化硫。在相同操作条件下,比较了传统的工业化 方法稀硫酸吸收法(千代田法)与本法的优劣,研究了液气化、二氧化硫浓度、三价铁离子浓度等因素对吸收效率的影响;分析了脱硫反应前后吸收率pH值、三价铁离子浓度的变化。研究结果表明:适宜的液气比(12.5L/Nm^3 以上)、二氧化硫浓度(1000-5000ppm)和三价铁离子浓度(0.6g/L以上)能使该法具有较高(>98%)的脱硫率。在常温常压操作条件下,微生物法的脱硫率远优于千代田法,具有一定的工业化价值。  相似文献   
95.
本文计对三峡库区紫色丘陵地区的土壤生态环境状况,提出了优化评价的总目标、评价指标体系和评价程序,探讨了单项指数评价方法的数学模型与基准参数,在此基础上,应用了层次分析与模糊数学的原理和方法,对紫色土生态优化进行综合评价,旨在为库区及库周生态与环境建设及经济综合开发提供依据。  相似文献   
96.
Environmental impact assessment (EIA) system has been established in China since 1973. In present EIA cases, there are four participants in general: governments, enterprises, EIA organizations and the public. The public has held responsible for both social costs and social duties. The public supervises social costs produced by enterprises discharging pollutant in EIA. However public participation is mostly deputized by governments, which severely weaken the independence of the public as one participant in EIA. In this paper, EIA refers to the different attitudes of the participants whose optional strategies may be described by a proper game model. According to disfigurements in EIA, three sides (governments, enterprises, and EIA organizations) dynamic iterative game theory, dynamic game theory of incomplete information, and perfect Bayesian equilibrium theory to analyze the reciprocity relation among governments, EIA organizations and enterprises. The results show that in a short period, economic benefit is preponderant over social benefit. Governments and enterprises both do not want to take EIA to reveal social costs. EIA organizations’ income comes from enterprises and the collusions are built between them to vindicate economic benefit. In a long run, social benefit loss caused by environmental pollution must be recuperated sooner or later and environmental deterioration will influence the achievements of economic benefit, so both governments and enterprises are certain to pursue high social benefit and willing to take EIA, helpful to increase private benefit. EIA organizations will make fair assessment when their economic benefit are ensured. At present, the public as silent victims can not take actual part in EIA. The EIA system must be improved to break the present equilibrium of three sides, bringing the public to the equilibrium to exert public supervision.  相似文献   
97.
Ethanol–gasoline-blended fuel was tested in a conventional engine under various air–fuel equivalence ratios (λ) for its performance and emissions. The amount of fuel injection was adjusted manually by an open-loop control system using a CONSULT controller. It was found that without changing throttle opening and injection strategy, λ could be extended to a leaner condition as ethanol content increased. The results of engine performance tests showed that torque output would increase slightly at small throttle valve opening when ethanol–gasoline-blended fuel was used. It was also shown that CO and HC emissions were reduced with the increase of ethanol content in the blended fuel, which resulted from oxygen enrichment. At an air–fuel equivalence ratio slightly larger than one, the smallest amounts of CO and HC and the largest amounts of CO2 resulted. It was noted that under the lean combustion condition, CO2 emission was controlled by air–fuel equivalence ratio; while under the rich combustion condition, CO2 emission is offset by CO emission. It was also found that CO2 emission per unit horse power output for blended fuel was similar or less than that for gasoline fuel. From the experimental data, the optimal ethanol content in the gasoline and air–fuel equivalence ratio in terms of engine performance and air pollution was found.  相似文献   
98.
Kim KB  Seo KW  Kim YJ  Park M  Park CW  Kim PY  Kim JI  Lee SH 《Chemosphere》2003,50(9):1167-1173
In this study, we tested phenolic compounds such as bisphenol A (BPA), 4-nonylphenol (NP), 4-octylphenol (OP) and 4-propylphenol (PP) by using glucose-6-phosphate dehydrogenase (G6PD) in estrogen sensitive human breast cancer cells (MCF-7 cells) and glutathione peroxidase (GPx) in female immature Sprague-Dawley (SD) rats. This study was designed to investigate whether phenolic compounds have estrogenic effects in these useful screening methods for endocrine disruptors. We chose 6 h as the incubation period for the G6PD assay through a preliminary experiment using 17beta-estradiol (E2). Above the concentration of 1 x 10(-8) M, BPA significantly increased the G6PD activity in a concentration-dependent manner, relative to the control. NP (over the concentration of 1 x 10(-9) M) also enhanced the G6PD activity by about 1.8 times that of the control. OP produced weaker effects on G6PD than NP, and showed a tendency to increase the G6PD activity. PP did not affect the G6PD activity. These results show that BPA and NP have the effect of enhancing G6PD activities in MCF-7 cells. In the in vivo GPx assay, both BPA and E2 significantly increased the uterus wet weights and dramatically enhanced uterine GPx activities in immature female rats in a dose-dependent manner. Treatment with NP (500 mg/kg/day) increased significantly both the uterine GPx activity and the uterus wet weights in immature female rats. OP (500 mg/kg/day) also caused a significant increase in uterine GPx activity, but had no effect on the uterus wet weights. This finding indicates that the change in uterine GPx activities could be a more sensitive parameter than that of uterus wet weights in immature rats. This study implies that phenolic compounds have a weak estrogenic effects.  相似文献   
99.
中国-喜马拉雅柴胡属的花粉形态及其系统学意义   总被引:1,自引:0,他引:1  
本文报道了中国-喜马拉雅柴胡属(BupleurumL.)24种,7变种,2变型的花粉形态研究结果,全部在光学显微镜和扫描电镜下作了比较观察。有关柴胡属花粉形态的研究,除大苞柴胡(B.euphorbioidesNakai)和红柴胡(B,scorzonerifoliumWilld.)外.其余均为首次报道,根据该属花粉粒的形态和萌发孔特征,其花粉形态可分为三个类型,即:近菱形角孔类型、矩形边孔类型及其二者之间的过渡类型。花粉形态资料支持德国植物系统学家德鲁特(O,Drude,1898)关于柴胡属的系统位置,将其隶于芹亚科(Apioideae),芹族(Apieae),葛缕子亚族(Carinae)。  相似文献   
100.
介绍了华阳发电有限责任公司综合污水治理工艺,并对其处理效果和经济效益进行分析,为同类污水的处理提供了工程实例。  相似文献   
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