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1.
<正> 随着创建卫生城市的开展,垃圾处理日益受到重视,无锡市建立的垃圾处理厂,对垃圾处理采用二次发酵工艺,即“好氧堆肥发酵”、“自然堆肥贮存发酵”。现将发酵结果报道如下。1 材料与方法1.1 实验室条件下(温度26±1℃,相对湿度60%±5%)饲养家蝇1龄蛆500条,家蝇蛹500只。1.2 透气塑料筒20只(自制),编号1~20号1.3 垃圾处理厂的垃圾处理采用2次发酵,第1次机械通风好氧堆肥发酵10d,取出后入库,再第2次自然堆肥贮存发酵10d。  相似文献   
2.
Gathering and eating mushrooms and other plants containing psychoactive substances has become increasingly popular among young people experimenting with drugs. Dried fly agaric Amanita muscaria fruiting bodies were eaten by five young persons (18-21 years of age) at a party in order to evoke hallucinations. Visual and auditory hallucinations occurred in four of them, whereas a 18-year-old girl lost consciousness. The following morning, she went to the Clinic of Toxicology. Due to the fact that not all the active substances present in the fly agaric have been identified, and some of them have an effect after a period of latency, the patient was admitted for several days of observation during which check-up examinations were performed. After four days without any problems, she was discharged. The poisoning regressed with no organ complications. The remaining persons who had eaten the fly agaric were free from any complaints.  相似文献   
3.
目的掌握西宁地区蝇类密度与季节消长规律,为蝇类防制提供科学依据。方法采用笼诱法。每个监测点设置1个配有新鲜饵料的天幕式捕蝇笼,放置8h(9:00~17:00),收集到的蝇类用乙醚杀死后分类,统计各蝇种数量,并计算蝇类密度。结果西宁市2010年平均蝇类密度为13.06只/笼;优势蝇种为厩腐蝇、新陆原伏蝇;蝇类季节消长呈单峰型,9月份达最高峰。结论孳生环境和防治措施是影响蝇类密度和种群的主要因素。蝇类防制应采取环境治理为主、化学防治为辅的综合防制措施,以达到降低蝇密度、控制传染病发生与流行的目的。  相似文献   
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5.
焚烧飞灰中含有可溶盐、重金属、痕量有机物及二恶英等物质,对环境和人体健康造成极大的危害。介绍了目前熔融处理、水泥固化、化学药剂稳定化等处理技术的研究进展,总结了飞灰资源化利用途径,提出了未来研究方向的建议。  相似文献   
6.
The present investigation assessed the applicability of incense stick ash, a novel and sustainable adsorbent for remediation of Victoria Blue dye from wastewater. Incense stick ash, without any physical and chemical treatment has been applied to investigate the influence of various experimental parameters as pH, loading of adsorbent, concentration, shaking time, temperature and ionic strength on Victoria Blue remediation in a batch operation. Incense stick ash was characterized using BET, DLS, SEM-EDS, FTIR and XRD techniques. BET surface area, pore volume and pore diameter of incense stick ash are obtained as 2.245 m2 g?1, 0.0118 cm3 g?1 and 21.02 nm, respectively. Average particle size of the adsorbent is obtained as 293.2 nm. Goodness of the fit of isotherm and kinetic model to the reported data was identified based on chi squared and coefficient of determination values. Isotherm and kinetic behavior was best represented by Freundlich and pseudo 2nd order equation, respectively. Boyd model confirmed involvement of film diffusion mechanism along with intra-particle for adsorption of Victoria Blue on incense stick ash. Maximum dye uptake was reported as 105.57 mg g?1. Thermodynamic study revealed spontaneous and favorable adsorption of Victoria Blue on incense stick ash at higher temperature. The performed elution and subsequent regeneration study implied desorption capability of incense stick ash and its applicability as a fresh adsorbent for further cycle of adsorption. The overall study implied scavenging potential of incense stick ash, a novel and sustainable adsorbent available at zero cost towards Victoria Blue removal.  相似文献   
7.
Fly ash—the residuum of coal burning—contains a considerable amount of fossilized particulate organic carbon (FOCash) that remains after high-temperature combustion. Fly ash leaks into natural environments and participates in the contemporary carbon cycle, but its reactivity and flux remained poorly understood. We characterized FOCash in the Chang Jiang (Yangtze River) basin, China, and quantified the riverine FOCash fluxes. Using Raman spectral analysis, ramped pyrolysis oxidation, and chemical oxidation, we found that FOCash is highly recalcitrant and unreactive, whereas shale-derived FOC (FOCrock) was much more labile and easily oxidized. By combining mass balance calculations and other estimates of fly ash input to rivers, we estimated that the flux of FOCash carried by the Chang Jiang was 0.21 to 0.42 Mt C⋅y−1 in 2007 to 2008—an amount equivalent to 37 to 72% of the total riverine FOC export. We attributed such high flux to the combination of increasing coal combustion that enhances FOCash production and the massive construction of dams in the basin that reduces the flux of FOCrock eroded from upstream mountainous areas. Using global ash data, a first-order estimate suggests that FOCash makes up to 16% of the present-day global riverine FOC flux to the oceans. This reflects a substantial impact of anthropogenic activities on the fluxes and burial of fossil organic carbon that has been made less reactive than the rocks from which it was derived.

Fossil particulate organic carbon (FOC) is a geologically stable form of carbon that was produced by the ancient biosphere and then buried and stored in the lithosphere; it is a key player in the geological carbon cycle (17). Uplift and erosion liberate FOC from bedrock, delivering it to the surficial carbon cycle. Some is oxidized in sediment routing systems, but a portion escapes and can be transported by rivers to the oceans (5, 810). Oxidation of FOC represents a long-term atmospheric carbon source and O2 sink, whereas the reburial of FOC in sedimentary basins has no long-term net effect on atmospheric CO2 and O2 (1, 9, 11). Exhumation and erosion of bedrock provide a natural source of FOC (2, 8), which we refer to as FOCrock. Human activities have introduced another form of FOC from the mining and combustion of coal. Burning coal emits CO2 to the atmosphere but also leaves behind solid waste that contains substantial amounts of organic carbon (OC) that survives high-temperature combustion (1214). This fossil-fuel-sourced carbon represents a poorly understood anthropogenic flux in the global carbon cycle; it also provides a major source of black carbon, which is a severe pollutant and climate-forcing agent (1215).Previous studies sought to quantify black carbon in different terrestrial and marine environments and to distinguish fossil fuel versus forest fire sources (1418). In this study, we focused on fly ash—the material left from incomplete coal combustion. As a major fossil fuel, coal supplies around 30% of global primary energy consumption (19, 20). Despite efforts to capture and utilize fly ash, a fraction enters soils and rivers; the resulting fossil OC from fly ash (FOCash) has become a measurable part of the contemporary carbon cycle (14). FOCash is also referred to as “unburned carbon” in fly ash (2125); it provides a useful measure of combustion efficiency and the quality of fly ash as a building material (e.g., in concrete) (2326). Industrial standards of FOCash content in fly ash have been established for material quality assurance (23, 24, 26, 27). However, the characteristics and fluxes of FOCash released to the environment, and how these compare to FOCrock from bedrock erosion, remain less well understood.To fill this knowledge gap, we examined the Chang Jiang (Yangtze River) basin in China—a system that allowed us to evaluate the influence of FOCash on the carbon cycle at continental scales. In the 2000s, China became the largest coal-consuming country in the world, with an annual coal consumption of over 2,500 Mt, equating to ∼50% of worldwide consumption (19, 20, 28). Coal contributed over 60% of China’s national primary energy consumption through the 2000s. A significant portion of this coal (approximately one-third) was consumed in the Chang Jiang (CJ) basin, where China’s most populated and economically developed areas are located (29). Significant amounts of fly ash and FOCash continue to be produced and consumed in the CJ basin. To determine the human-induced FOCash flux, we investigated the FOCash cycle in the CJ basin. We characterized OC in a series of samples including fly ash, bedrock sedimentary shale, and river sediment through multiple geochemical analyses. We then estimated the CJ-exported FOCash flux and evaluated how human activities modulated FOC transfer at basin scales. We found that in the CJ basin, coal combustion and dam construction have conspired to boost the FOCash flux and reduce the FOCrock flux carried by the CJ; as a result, these two fluxes converged over an interval of 60 y.  相似文献   
8.
目的:调研四川市售白芍饮片质量。方法:随机采购四川市售白芍饮片16批,参照现行2010版药典的规定,测定饮片水分、总灰分、水溶性浸出物,并采用HPLC法测定芍药苷含量。结果:16批次白芍饮片中仅3批次芍药苷的量符合药典规定,9批次水分符合药典规定。结论:白芍饮片存在的质量问题主要是芍药苷含量和水分含量不合格。针对导致白芍药材或饮片质量问题的多种原因,药品监督管理部门应加强监督管理,规范饮片市场。  相似文献   
9.
This research focuses on an evaluation of mineral phase and structure transformations in Class F fly ash-based geopolymer systems. The research also studies the strength response of geopolymers when exposed to temperatures between 25 and 800 °C. The purpose of this research is to understand the processes that occur in alkali-activated systems within a wide range of high-working temperatures. The XRD, SEM, and DTA/TG analyses performed for the alkali-activated compositions after exposure to different temperatures confirmed a direct correlation of structural transformations with strength performance. The detrimental effect of sodium hydrocarbonate Na3(HCO3)(CO3) 2H2O or trona contained in one of the fly ash products was observed for the corresponding alkali-activated composite under high-temperature exposure between 600 and 800 °C. It was also detected that a high-temperature interval of 400–800 °C created favorable conditions that helped to form nanosized nepheline crystals and an additional vitreous substance that also contributed to a denser alkali-activated matrix.  相似文献   
10.
Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics.  相似文献   
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