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651.
Environmental Science and Pollution Research - Samples of orange patinas found on a limestone window tracery and an ornament of the Batalha Monastery have been investigated by X-ray...  相似文献   
652.

An updated systematic review was conducted to assessing on the association between indoor air pollution caused by household energy consumption and childhood pneumonia in low- and middle-income countries. We performed a meta-analysis from the electronic databases of PubMed, Cochrane library, Web of Science, EMBASE. Studies were selected when they reported childhood pneumonia or ALRI in relation to indoor air pollution resulted from solid fuel. Studies must provide results on exposure prevalence of children aged below 5 years from Asia or Africa. We devoted ourselves to identifying randomized controlled experiments and observational epidemiological researches, which revealed the relation between household usage of solid fuel and childhood pneumonia. Among 1954 articles, 276 were reviewed thoroughly and 16 conduced to such a meta-analysis. It was found that there is a significant relationship between the solid fuel combustion and increasing risk of childhood pneumonia (OR?=?1.66, 95%CI 1.36–2.02). The summary odds ratios from biomass use and mixed fuel use were, respectively, 1.86 (95%CI 1.15–3.02) and 1.58 (95%CI 1.38–1.81), with substantial between study heterogeneity (I2?=?87.2% and 29.2%, respectively). According to the subgroup analysis along with the meta-regression analysis, the risk of using solid fuel in Asian regions is higher than that in African regions. Studies based on non-hospital participates (I2?=?49.5%) may also a source of heterogeneity. We found that indoor air pollution generated by the usage of solid fuel might be a significant risk factor for pneumonia in children and suggested improving the indoor air quality by promoting cleaner fuel will be important in undeveloped countries.

  相似文献   
653.
Environmental Science and Pollution Research - An increasing number of studies investigated the association between air pollution during pregnancy and the risk of eczema in offspring. However, no...  相似文献   
654.
Ancient paddy soils from the Neolithic age in China’s Yangtze River Delta   总被引:8,自引:0,他引:8  
Identifying prehistoric irrigated rice fields and characterizing the beginning of paddy soil development are important for a better understanding of human development and agricultural history. In 2003, paddy soils and irrigated rice fields buried at a depth of 100–130 cm were excavated at Chuo-dun-shan in the Yangtze River Delta, close to Suzhou, China. The fields of sizes between 1.4 and 16 m2 were surrounded with ridges that were connected to ditches/ponds via outlets to control the water level within the fields. Many carbonized and partly carbonized rice grains with an age of 3,903 B.C.(measured 14C age 5,129±45 a BP) were recovered. The surface layers of these buried paddy fields showed a high content of soil organic matter and a considerable high density of rice opals. The latter were identified to derive from Oryza spp. Solid-state 13C nuclear magnetic resonance spectroscopy revealed aromatic carbon (C) as the predominant organic C form in the fossil surface layer. This is expected, if the major source represents burnt rice and straw. In summary, our data are in agreement with new evidences indicating that in China, paddy soils and irrigated rice cultivation were initiated and developed more than 6,000 years ago.  相似文献   
655.
Cheng CY  Liu LL  Ding WH 《Chemosphere》2006,65(11):2152-2159
The occurrence and distribution of alkylphenols (APs, i.e., 4-tert-octylphenol (4-t-OP) and 4-nonlyphenol isomers (4-NP)) in oysters (Crassostrea gigas), snails (Thais clavigera), coastal water and coastal sediments of the western coast of southern Taiwan are investigated. Alkylphenols were present in all matrices of interest: in water, ranging from 61 to 370 ng/l, in sediments, ranging from 27 to 190 ng/g, and in biota samples (i.e., oyster and snail), ranging from 20 to 5190 ng/g. Statistical analysis indicated that the probability distribution of most determined concentrations in oyster and snail samples was log-normal distribution. The bioaccumulation of APs resulted in a seasonal variation with respect to their compositions and concentrations in oyster and snail samples. For oysters, concentrations of APs in winter exceeded those in summer. In contrast, those in snails in summer exceeded those in winter. Estimated biomagnification factors of APs from snails to oysters ranged from 1.4 to 4.3 in summer, and 0.5 to 0.8 in winter on the dry weight basis. The results suggested that seasonally mediated physiological changes, such as dilution caused by growth, biotransformation and metabolism, may affect the bioaccumulation of APs in according to season and organism.  相似文献   
656.
通过土壤对石化工业废水的吸附试验分析,可以预测工程废水对地下水的影响情况,对保护当地地下水水质,指导工程环境建设具有十分积极的作用  相似文献   
657.
淮北台DSQ型与SSQ-2I型倾斜仪观测资料的对比分析   总被引:2,自引:0,他引:2  
对淮北台DSQ型水管和SSQ-2I型水平摆倾斜仪观测资料质量从一般指标和内精度指标进行定量判定,结果表明水管仪观测质量较高,稳定性不及水平摆倾斜仪,观测数据均受大风和降雨影响。因仪器工作原理、技术参数等因素不同,记录到同震形变波在响应延迟、最大振幅和形态特征等方面存在一定差异。  相似文献   
658.
Subgrid-scale (SGS) modeling is a long-standing problem and a critical component in the large-eddy simulation (LES) of atmospheric boundary layer. A variety of SGS models with different levels of sophistication have been proposed for different needs, such as Smagorinsky's (1963) eddy viscosity model, Mason and Thomson's (1992) stochastic backscattering model, and Sullivan et al.'s (1994) near surface model. A modified Smagorinsky SGS model has been used in the LES version of Terminal Area Simulation System (TASS-LES). It has successfully simulated the buoyancy-dominated, convective atmospheric boundary layer flows, while simulations of the shear-dominated, slightly unstable, neutral, and stably stratified boundary layer flows are not so good. For the later, we used a simpler version of Sullivan et al.'s subgrid-scale model in which turbulent kinetic energy equation is not included and the model is still the first-order closure. A momentum profile matching approach is adopted in the proposed model. A series of simulations for shear-dominated, slightly unstable and neutral boundary layers are performed using different subgrid-scale models and different grid resolutions. The results are compared with those of Sullivan et al. (1994) and with empirical similarity relations for the surface layer. The simulations with the new SGS model appear to be far more satisfactory than those with the modified Smagorinsky model.  相似文献   
659.
混凝剂处理染料及其中间体废水应用   总被引:5,自引:0,他引:5  
带磺酸基的染料及其中间体废水是一大处理难题,通常大多数絮凝剂不适用。通过研究发现,聚合硫酸亚铁与阳离子聚丙烯酰胺作为絮凝剂处理该类废水,具有良好的处理效果。  相似文献   
660.
从"人、机、料、法、环"5个方面,阐述了如何做好泄漏检测与维修(LDAR)工作过程的质量控制,并针对性地提出了部分具体质量控制措施。  相似文献   
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