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121.
牛粪自然好氧发酵微生物变化规律   总被引:7,自引:0,他引:7  
以新鲜牛粪进行好氧堆肥,每间隔3d取样,以牛肉蛋白胨、高氏一号、PDA、豆芽汁为培养基,以稀释法,进行发酵微生物分离、培养、计数和鉴定.结果表明,新鲜牛粪中微生物主要为细菌;发酵过程中,细菌数量大于放线菌、霉菌约104~ 105倍,细菌是发酵过程中的优势微生物;中温性细菌是升温阶段主要作用菌群;嗜热放线菌及嗜热细菌是高温阶段优势菌群;霉菌是降温阶段优势菌群.进一步鉴定表明,细菌类群中的芽孢杆菌、纤维单胞菌,放线菌类群中的小多孢菌、小单孢菌、高温放线菌,霉菌类群中的木霉、曲霉、青霉等为发酵过程中的优势种类.酵母菌未参与发酵过程.  相似文献   
122.
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term 'common-garden' experiment to disentangle the effects of species' wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation.  相似文献   
123.
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term ‘common-garden’ experiment to disentangle the effects of species’ wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation.  相似文献   
124.
Falcon离心分选机回收废弃电路板金属的灰色模型研究   总被引:1,自引:0,他引:1  
电子废弃物的资源化既能实现资源的二次利用,又能防止环境污染,具有重要的理论意义和应用价值。论述了Falcon离心分选机分选电路板的机制,并对小于0.5mm废弃电路板中金属富集体进行了分选试验。运用GM(0,N)模型对离心复合力场中回收废弃电路板建立了分选灰色模型,与实际分选结果比较表明,该模型精度很高。该模型可以对离心复合力场中回收废弃电路板金属的分选试验结果进行预测。  相似文献   
125.
新沂河污水净化生态工程研究   总被引:3,自引:0,他引:3  
苏北水环境综合整治方案提出了“清污两制、控源导流”的水污染控制战略。以这一战略为指导,实施江苏省水污染集中控制两线工程。对北线工程新沂河污水生态工程的背景、工程方案与设计、污水系统水质模拟进行了详尽论述。  相似文献   
126.
A process for reclaiming the materials in spent alkaline zinc manganese dioxide (Zn–Mn) batteries collected from the manufacturers to prepare valuable electrolytic zinc and LiNi0.5Mn1.5O4 materials is presented. After dismantling battery cans, the iron cans, covers, electric rods, organic separator, label, sealing materials, and electrolyte are separated through the washing, magnetic separation, filtrating, and sieving operations. Then, the powder residues react with H2SO4 (2 mol L?1) solution to dissolve zinc under a liquid/solid ratio of 3:1 at room temperature, and subsequently, the electrolytic Zn with purity of ?99.8% is recovered in an electrolytic cell with a cathode efficiency of ?85% under the conditions of 37–40 °C and 300 A m?2. The most of MnO2 and a small quantity of electrolytic MnO2 are recovered from the filtration residue and the electrodeposit on the anode of electrolytic cell, respectively. The recovered manganese oxides are used to synthesize LiNi0.5Mn1.5O4 material of lithium-ion battery. The as-synthesized LiNi0.5Mn1.5O4 discharges 118.3 mAh g?1 capacity and 4.7 V voltage plateau, which is comparable to the sample synthesized using commercial electrolytic MnO2. This process can recover the substances in the spent Zn–Mn batteries and innocuously treat the wastewaters, indicating that it is environmentally acceptable and applicable.  相似文献   
127.
In this study, we examined three horizontal and vertical soil profiles along a sewage drainage ditch in order to determine the spatial distribution of Cu, Pb, and Zn in soils and to assess the bioavailability and potential ecological risks associated with these metals in a potential groundwater source area. Results showed that the concentrations of Cu, Pb, and Zn were approximately at background level, suggesting that human activities (industrial and agricultural pollution) had a negligible influence on these metals in soil, and that the concentrations reflected the natural background levels in the study area. Cu, Pb, and Zn concentrations were slightly higher in topsoil (0–20 cm) than deeper in the soil profile. Using a modified BCR sequential extraction method to evaluate the mobility and bioavailability of metals showed that the potential bioavailability sequence of Cu, Pb, and Zn at three depths in the soil profile was in the order Cu?≈?Pb?<?Zn. The potential ecological risk from the metals was evaluated using risk assessment code, and the results suggest that Cu and Zn pose no or low risk, while there is a low or medium risk from Pb. Results from groundwater monitoring showed that the groundwater was not polluted by leaching from soil.  相似文献   
128.
Environmental Science and Pollution Research - Life cycle assessment (LCA) is widely used to quantify the environmental performance of buildings. Recently, the potential temporal variations in the...  相似文献   
129.
于2006年至2007年在台州电子垃圾拆解区和市区对照点采集了不同季节的大气细颗粒物样品,利用离子色谱对颗粒物中氯离子(Cl-)、硝酸根(NO3-)、硫酸根(SO42-)、草酸根(C2O42-)、钠离子(Na+)、铵离子(NH4+)、钾离子(K+)、钙离子(ca2+)、镁离子(Mg2+)等水溶性离子进行r分析.结果表明...  相似文献   
130.
Under the globalization, the coastal China becomes a hot area of the international manufacturing investment due to its priority location, excellent environment, lower labor and land costs, etc. However, the fast industrialization has aroused the great demolishment to the local ecological environment. For example, the heavy water eutrophication in Taihu Lake has affected the source of drinking water for the cities around the lake. Anyway, in order to keep the economic increase and reduce the resource ex- pense and pollution at the same time, it is necessary to encourage the greening of industrial enterprises actively for sustainable de- velopment. On the basis of the investigation of industrial enter- prises in Wuxi city within Taihu Basin, the relatively developed region in coastal China, this paper analyzed the development process of green industry. This article concluded that governmen- tal principal is the main pressure for enterprises to protect envi- ronment while the market factor plays a part role. Moreover, en- terprises in the high technology development zone work better in environmental protection than those in the villages and towns, while the large enterprises work better than those small enterprises.  相似文献   
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