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121.
医疗垃圾的特性和成分是改善焚烧装置设计、运行及控制性能的重要参数.为了研究医用玻璃对医疗垃圾焚烧炉的影响,从医疗废物处置中心采集了玻璃和灰渣样品,分析了其化学组分和熔融温度.与煤灰成分相比,医用玻璃中的SiO2和碱金属氧化物含量较高.通过不同玻璃间的比较,总结了化学组分对熔融温度的影响.软化温度随着SiO2、CaO含量的增加而升高,但随B2O3、Na2O含量的增加而迅速降低.改变不同玻璃的混合比例.研究了混合玻璃的熔融特性.利用煤灰结渣指数对医疗垃圾灰渣的结渣倾向进行了判定.结果显示,仅沾污指数能够对灰渣得出适宜的判别.  相似文献   
122.
牟建 《环境科学与管理》2011,36(10):121-124,134
介绍常用玻璃量器的检定原理和方法,并详细叙述了修正系数K(t)的数学模型建立的全过程。全面分析了模型中所有参数的相关性,在此基础上对模型进行了优化,去除了模型中次要参数,大大简化了数学模型,同时,修正了JJG196-2006《常用玻璃量器检定规程》中忽略大气压力参数的影响,导致可能出现检定结论出错的问题,并给出了优化后的数学模型表达式,分别给出了大气压力在110~50KPa之间的钠钙玻璃和硼硅玻璃量器的K(t)值表。  相似文献   
123.
Construction utilization of foamed waste glass   总被引:5,自引:0,他引:5  
Foamed waste glass (FWG) material is newly developed for the purpose to utilize the waste glassware and other waste glass. FWG has a multi-porous structure that consists of continuous or discontinuous voids. Hence lightweight but considerable stiffness can be achieved. In the present study, the manufacture and engineering properties of FWG are introduced first. Then, the utilizations of FWG are investigated in laboratory tests and field tests. Some case studies on design and construction work are also reported here. Through these studies we know that the discontinuous void material can be utilized as a lightweight fill material, ground improvement material and lightweight aggregate for concrete. On the other hand, the continuous void material can be used as water holding material for the areenina of around slope and rooftop, and as clarification material for water.  相似文献   
124.
介绍了发达国家处理和再利用废玻璃的经验,提出我国应借鉴发达国家经验,从科研、政策、法律等方面加强废玻璃的再利用工作。  相似文献   
125.
孙阳 《环境与发展》2020,(4):101-103
再生水深度处理系统的设计简述,以及调试运行对设计参数的修正和调整,提出了对今后系统设计应注意的细节。  相似文献   
126.
包装垃圾是由废弃的包装物产生的固体垃圾,约占我国城市生活垃圾的1/3,虽然政府进行了必要回收,但仍有1/3以上的塑料、玻璃等包装物没能被有效回收利用,成了填埋场的主要填埋物,造成了环境污染和土地、石油等不可再生资源大量浪费。从回收利用和源头减量两方面提出包装垃圾的应对,一是对包装垃圾按来源、成分等进行详细分类,并建议回收处置方法;二是从制定行业政策方面来减少过度包装和扶持再生资源行业健康发展,有效处置包装垃圾等可再生资源。  相似文献   
127.
水中三氯甲烷和四氯化碳的气相色谱分析,无论是检测自来水的标准方法还是环境监测统一方法,都规定为顶端空间气相色谱法.新近文献报道测定硝基苯类化合物也采用顶端空间法.在这些方法中都使用50ml比色管作为气液平衡瓶,比色管用医用反口橡皮塞封口,本改进设计了玻璃球封口比色管作为气液平衡瓶,利用乳胶管中玻璃球的滚动来达到密封针孔的目的,从而提高了分析方法的精密度和准确性.  相似文献   
128.
Lin K  Gan J 《Chemosphere》2011,83(3):240-246
Presence of pharmaceuticals at trace levels in recycled water is an emerging issue impacting the beneficial reuse of treated wastewater, including practices such as irrigation and groundwater recharge in arid and semi-arid regions. To assess the environmental risks of irrigation with recycled water containing such micropollutants, in this study we evaluated sorption and degradation of five pharmaceuticals that are antibiotic and anti-inflammatory drugs in two soils collected from arid regions. Naproxen and trimethoprim showed moderate to strong sorption, while the sorption of diclofenac, ibuprofen and sulfamethoxazole was negligible in both soils. Under aerobic conditions, the studied compounds were susceptible to microbial degradation with half-lives varying from 4.8 to 69.3 d. Apart from sulfamethoxazole, the other compounds were relatively persistent under anaerobic conditions as indicated by a negligible loss over 84 d of incubation or half-lives >50 d. The degradation of the selected pharmaceuticals was influenced by microbial activities, oxygen status in the soil, soil type and compound characteristics. The poor sorption and relative persistence of diclofenac and ibuprofen under anaerobic conditions suggest that the two chemicals may pose a high leaching risk when using recycled for irrigation or groundwater replenishment.  相似文献   
129.
As a result of the changes that occur during their use, used engine oils tend to differ in chemical and physical composition from a virgin oil. In general recycled oils have: much higher water and sediment levels than virgin oil; relatively higher concentrations of organic compounds (oxidation products); and relatively higher levels of metals such as Fe, Cd, Cr, Pb, etc. Therefore, the aim of this work was to investigate, assess and to observe, by means of the physical and the chemical properties of the oils, atomic absorption (AA), inductive couple plasma (ICP) and Fourier transform infrared (FTIR) analyses the extent of the differences occurring between the virgin and recycled oil. In important part of this work was also the development of analytical techniques based on the use of FTIR spectroscopy; in relation to the rapid analysis of lubricants; in particular for the differentiation of virgin and recycled oil. The results obtained were expected to be useful for differentiation purposes, providing information on whether the metal concentrations and oxidation products could be an appropriate feature for differentiating a particular oil sample from the others. This work is categorized into a two-step procedure. Firstly, an evaluation of a typical FTIR spectrum of an engine oil sample (mono- and multigrade) is presented. The broad feature centered at 1716 cm(-1) is due to the presence of carbonyl containing degradation products of oil. A band observed at 1732, 1169, 1154 and 1270 cm(-1) assigned to the polymethacrylate stretching vibrations, allows the determination of viscosity modifier and pour point depressant additives. The observed differences in the specific spectral bands (1732, 1169, 1154 and 1270 and 1716 cm(-1)) are investigated and discussed. Secondly, an analytical technique for the measurement of the levels of the wear metals is also applied.  相似文献   
130.
Background, aim, and scope  The first step in the restoration of a medieval stained glass window is the evaluation of its degree of degradation. This implies the study of the chemical composition of the stained glass as well as the new mineral phases developed on its surface (patinas). Patinas are clearly related to glass composition, time, environmental conditions, microenvironments developed in local zones, bioactivity, physical and chemical factors, etc. This study was carried out on patinas developed in selected Na-rich stained glass of the Santa Maria de Pedralbes Monastery (Barcelona, Spain). The location of this monument in the city (about 5 km from the shoreline and close to the Collserola hill flank) helped to determine the environmental conditions in which patinas developed. The aim of our study was to characterize the patinas formed on the surface of the selected glass of this monastery in order to understand the role of the chemical composition of the original glass (Na-rich) as well as the environmental conditions in which they developed. Materials and methods  Powdered samples of two different color-type patinas (ochre-orange and brownish) were collected in the external and internal parts of the stained glass windows of the Prebystery and Chapter House of the Pedralbes Monastery by using a precision (odontological) drill. These patinas were subsequently analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Results  XRD analyses evidenced the presence of sulfates (gypsum and thenardite), calcite, Ca-oxalates (whewellite and weddellite), and quartz forming part of the patinas. Although these mineral phases can be found in both color-type patinas, whewellite and thenardite are more common in the ochre-orange patinas. The results obtained were validated by the FTIR measurements. It has been observed, when thenardite is present, that gypsum occurs as traces. Thenardite is in most of the cases associated with whewellite and mainly occurs in the internal parts of the glass. In contrast, weddellite is limited to the absence of thenardite and whewellite and to the external parts of the stained glass. Quartz is present in all the patinas independent of their location and color. Calcite also occurs in many samples. It appears in both color-type patinas and, in some cases, is associated to the presence of weddellite but not to whewellite and/or thenardite. Discussion  Glass composition together with environmental conditions and location of the patinas (internal or external parts of the stained glass window), as well as the provenance of the glass within the monastery, are the main factors that define the development of the new mineral phases. Moreover, the action of microorganisms, when present, can also strongly influence the development of some mineral phases. For example, the formation of calcite in the external parts of the stained glass (associated with the presence of oxalates) is related to the action of microorganisms. When calcite is formed in the internal parts of the glass and it is not associated with the presence of Ca-oxalates, an inorganic origin can be invoked. The presence of weddellite requires a very humid microenvironment with very little exposure to sunlight. In fact, this mineral phase has only been observed in the external parts of some glass located in the humid and shady side of the monastery. Whewellite (which only appears in the internal parts) needs a low degree of relative humidity. It has been observed that sulfur precipitating in basically one mineral phase (thenardite or gypsum) depends on the microenvironmental conditions of the moment and the glass composition. When thenardite occurs, it can be maintained that the original glass is of Na composition. The occurrence of quartz in all samples is interpreted as being due to the deposition of atmospheric particulate matter. The color of the patinas can be originated by different processes (presence of carotenes, organic pigmentation, atmospheric contamination, etc.). Conclusions  In the case of moderately weathered stained glass windows, the combination of XRD and FTIR techniques is very useful to obtain a fast preliminary evaluation of the degree of weathering of a stained glass window. The presence of specific mineral phases in the patina (e.g., thenardite) confirms the Na composition of the original stained glass. This is important since Na-rich glass underwent a lesser degree of weathering than K- or K-Ca-rich glass. However, their absence cannot preclude other possibilities. It has been extensively evidenced through time that environmental conditions play an important role on the formation of the different mineral phases which form part of the patinas. Recommendations and perspectives  The first step in the restoration of a stained glass window is the evaluation of the degree of deterioration of the glass. This evaluation includes a chemical analysis of the glass as well as a characterization of the patinas developed on their surfaces. The obtained results will be essential in order to define the best restoration practices to be followed.  相似文献   
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