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31.
滇池和洱海湖滨带水生植被状况与水质的关系研究 总被引:3,自引:0,他引:3
在滇池和洱海的湖滨带各设置了6个具有不同水生植被状况的采样点,于2010年8月-2011年5月对水温、pH、ORP、电导率、营养盐(总氮和总磷)、叶绿素a及3种DNA病毒等水质指标进行了现场或采样分析。结果表明,两湖泊中营养盐含量高的湖滨带(滇池草海和洱海沙坪湾),由于水生植物覆盖度高,湖水保持了叶绿素a含量低的状态。对洱海湖滨带的水质分析结果表明,洱海水质有较明显的季节性变化。分析表明,与水温相比,营养盐浓度可能是影响藻类生物量的更重要的因素。3种DNA病毒检测结果初步表明,水生植物不仅能控藻,而且对病毒也有抑制作用。 相似文献
32.
33.
Decolorization and estrogenic activity of colored livestock wastewater after electrolysis treatment 总被引:1,自引:0,他引:1
Hotaka Kai Yasuhiro Ishibashi Taiki Mori Hiroshi Ishibashi Isao Kawaguchi Hiroki Ohwaki Takehiro Takemasa Koji Arizono 《Journal of Material Cycles and Waste Management》2010,12(2):128-135
Livestock wastewater is treated by activated sludge treatment. Untreated livestock wastewater has high estrogen activity because
animal excreta contains estrogen. When activated sludge treatment is applied, the estrogen activity declines or is lost. However,
the color of treated livestock wastewater is deep brownish-red because of the decomposition of organic compounds or the synthesis
of metabolites. Discharging colored wastewater to the environment could cause some problems, so it is necessary to decolorize
colored wastewater before it is discharged. It has been suggested that electrolysis decolorization technology is suitable
for treating colored wastewater; however, the process produces volatile organic compounds (VOCs). In fact, little research
has been conducted with reference to estrogen activity in wastewater that has undergone electrolysis, especially on the contribution
of the electrolysis decolorization process to estrogen activity, i.e., the possibility of resynthesis of some substance with
estrogen activity due to resolved and metabolized colored components. In this study, the concentration of VOC was measured
for various electrolysis conditions, and estrogen activity was examined using a yeast two-hybrid assay. From the results,
decolorization of colored livestock wastewater by electrolysis was possible, and the VOC generation during electrolysis could
be controlled depending on the electrolysis conditions. Estrogen activity in colored livestock wastewater disappeared on electrolysis
decolorization. 相似文献
34.
Bottom ash from municipal solid waste incineration (MSWI) is a main type of waste that is landfilled in Japan. The long-term elution of organic matter from the MSWI bottom ash layers is a concern because maintenance and operational costs of leachate treatment facilities are high. In closed system disposal facilities (CSDFs), which have a roof to prevent rainfall from infiltrating into the waste layers, water must be supplied artificially and its quantity can be controlled. However, the quantity of water needed and how to apply it (the intensity, period and frequency) have not been clearly defined. In order to discuss an effective watering plan, this study proposes a new washout model to clarify a fundamental mechanism of total organic carbon (TOC) elution behavior from MSWI bottom ash layers. The washout model considers three phases: solid, immobile water and mobile water. The parameters, including two mass transfer coefficients of the solid-immobile water phases and immobile-mobile water phases, were determined by one-dimensional column experiments for about 2 years. The intensity, period and frequency of watering and other factors were discussed based on a numerical analysis using the above parameters. As a result, our washout model explained adequately the elution behavior of TOC from the MSWI bottom ash layer before carbonation occurred (pH approximately 8.3). The determined parameters and numerical analysis suggested that there is a possibility that the minimum amount of water needed for washing out TOC per unit weight of MSWI bottom ash layer could be determined, which depends on the two mass transfer coefficients and the depth of the MSWI bottom ash layer. Knowledge about the fundamental mechanism of the elution behavior of TOC from the MSWI bottom ash layer before carbonation occurs, clarified by this study, will help an effective watering plan in CSDFs. 相似文献
35.
Inaba R Furuichi T Komatsu T Tanikawa N Ishii K 《Waste management (New York, N.Y.)》2009,29(1):214-223
In Japan, most farm animal excreta has been stored directly on farmland. Runoff from this storage has often caused water pollution. Biogasification is anticipated as an important technology to manage excreta properly, but complex problems hinder its introduction. Economic aspects of management have been especially difficult for dairy farmers. For this study, structural problems regarding introduction of biogasification into dairy farming were identified. Subsequently, a desirable system of dairy farming including biogasification was suggested, and an evaluation model of the financial balance was constructed. A case study using current financial balances of several systems of dairy farming was evaluated using the constructed model and actual data. The systems were based on several policy alternatives including the suggested system mentioned above. Results show that a farmer can obtain sufficient income from a system featuring centralization of dairy housing and biogasification facilities and coordinated management by over six farmers. 相似文献
36.
Hitoki Matsuda Hiroki Kageyama Yuuki Kawaguchi Shohichi Osada Mitsuhiro Kubota 《Journal of Material Cycles and Waste Management》2014,16(4):677-683
Dynamic studies on the volatilization of lead from CaO–SiO2–Al2O3 molten slags were conducted in a lab-scale melting furnace from 1623 to 1773 K under different mixed gas atmospheres of CO 0.05–0.3 atm to CO2 0–0.3 atm to N2 (balance), HCl 1.7 × 10?3–6.7 × 10?3 atm to N2 (balance), and H2S 3.0 × 10?4 to 1.7 × 10?3 atm to N2 (balance). The slag samples consisted of the mixed powders of 20–50 wt% CaO, 30–60 wt% SiO2, and 10–40 wt% Al2O3, containing 2000 ppm PbO.Results showed that the rates of volatilization of lead from the CaO–SiO2–Al2O3 molten slags under the N2–CO–CO2, N2–HCl, and N2–H2S gas atmospheres were higher than those under the simulated air (N2–O2), which increased with CO, HCl, and H2S partial pressures. At \(p_{{HCl}}\) = \(p_{H_{2}S}\) = 1.7 × 10?3 atm, the apparent rate constants for the volatilization of lead under the N2–H2S and N2–HCl gas atmospheres were nearly equal, which increased with a rise in temperature. Results also showed that the rate of volatilization of lead from the molten slag decreased drastically with the increasing viscosity of the molten slag, in the viscosity range lower than 3 Pa s. Consequently, the volatilization of lead from the CaO–SiO2–Al2O3 molten slag was significantly influenced by CO, HCl, and H2S partial pressures and by the viscosity of the molten slag. 相似文献
37.
Masahiko Yoshino Hiroki Osawa Akinori Yamanaka 《Journal of Manufacturing Processes》2012,14(4):478-486
In this paper, three kinds of self-organization processes for metal nano-dot array fabrication are compared; one is the conventional thermal dewetting, another is thermal dewetting of a grid patterned deposited metal layer, the other is thermal dewetting of a metal layer deposited on a patterned substrate. In these processes, nano plastic forming technique is utilized for patterning of groove grid. Effects of process conditions on nano-dot formation, such as substrate material, deposited metal, thickness of deposited layer, annealing condition, are experimentally studied. Also, effect of grid patterning on improvement of nano-dot array formation is studied. It is shown that grid patterning on a deposited metal layer is effective to improve alignment and configuration of nano-dot array. 相似文献
38.
In order to develop an effective recycling system for obsolete Liquid Crystal Displays (LCDs), which would enable both the leaching of indium (In) and the recovery of a pure glass fraction for recycling, an effective liberation or size-reduction method would be an important pre-treatment step. Therefore, in this study, two different types of liberation methods: (1) conventional grinding, and (2) electrical disintegration have been tested and evaluated in the context of Life Cycle Assessment (LCA). In other words, the above-mentioned methods were compared in order to find out the one that ensures the highest leaching capacity for indium, as well as the lowest environmental burden. One of the main findings of this study was that the electrical disintegration was the most effective liberation method, since it fully liberated the indium containing-layer, ensuring a leaching capacity of 968.5mg-In/kg-LCD. In turn, the estimate for the environmental burden was approximately five times smaller when compared with the conventional grinding. 相似文献
39.
Eiji?FujimoriEmail author Kazuaki?Minamoto Seiko?Iwata Koichi?Chiba Hiroki?Haraguchi 《Journal of Material Cycles and Waste Management》2004,6(1):73-79
The elemental composition of the industrial waste incineration bottom ash (IWIBA) samples collected from three different types of incinerator with different kinds of wastes were compared. The major-to-ultratrace elements in the IWIBA samples were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). As a result, ca. 40 elements in the concentration range from milligrams per gram to submicrograms per gram could be determined with relative standard deviations of less than 5%. The IWIBA sample from petrochemical wastes contained lower concentrations of the elements, because fewer mineral constituents were contained in the input waste materials. On the contrary, the elemental concentrations in the IWIBA sample from industrial solid wastes provided the highest values for most elements, while the elemental compositions of the IWIBA sample from food wastes were similar to those of municipal solid waste incineration bottom ash. In addition, it was found from the analytical results that the levels of various heavy metals such as Cr, Mn, Fe, Ni, Cu, As, Zr, Mo, Sb, Ba, and Pb were higher in the IWIBA samples than in municipal solid waste incineration bottom ash. The enrichment factors of the elements in the IWIBA samples were estimated from the analytical results to compare the elemental distributions in incineration bottom ashes in relation to their mining influence factors, which are the indices for human use of the elements. 相似文献