济钢除尘风机及风机出口噪声治理成功案例

济钢球团竖炉工艺除尘风机因场地受限建设在办公区域内,致使办公室的室内外噪音检测超标,为了保证正常生产办公秩序,采用隔声罩原理对除尘风机及风机出口噪声进行降噪处理,在解决风机出口噪声问题的同时,较好地解决了烟囱传播噪声的达标问题。     

Structure and diversity of Erica ciliaris and Erica tetralix heathlands at different successional stages after cutting

In NW Europe, it is known that cutting is a useful tool for managers with regard to decisions about the conservation and management of wet heathlands. Nevertheless it is rarely described quantitatively in the international literature. In Spain, knowledge about this is scarce or lacking. In this study, twenty communities were selected in Galicia (NW Spain) that would represent from one to four stages of vegetation development after cutting. Two 5?×?5?m plots were established for each stage to characterise the vegetation on the basis of its species composition, frequency values, vertical structure and linear cover features. The Diversity Shannon index was calculated and multivariate analyses were performed. As succession advanced, notable changes were produced in the cover of dominant species, Erica ciliaris and Ulex gallii in the first stages and Erica tetralix and Genista berberidea in mature ones. Also, the species richness decreased because of the reduced number of herbs species in the mature stages and, finally, the cover values are indicators of the degree of vegetation development, together with the other parameters of height, overlayering or diversity. Cutting is a useful tool for management of heathlands because the existence of vegetation units belonging to different succession stages increases the internal diversity of communities. On the other hand, the vertical and horizontal structure reflects the formidable resilience of the vegetation community to this practice. This study offers a global vision of the dynamics of wet heathlands after cutting, with very useful ecological information that can be used by the people responsible for their management.     

潞城市大气PM_（10）中化学元素分布特征

利用ICP-AES分析了潞城市采暖期和非采暖期4个不同功能区PM10样品中16种化学元素,对不同元素的时空分布特征进行了研究,并采用富集因子和主成分分析初步研究了潞城市PM10中元素的主要来源。结果表明,潞城市PM10中重金属污染较为严重,且各元素在采暖期的平均浓度均明显高于非采暖期。PM10中Ca、V、Cr、As、Ni、Mn、Cu、Zn、Al和Pb的富集因子EF〉10,主要来源于人为污染;而Na、Mg、Si、Fe和K的EF〈10,除部分来自人为活动外,主要来自土壤风沙等自然来源。主成分分析结果显示,潞城市PM10中元素的主要来源按贡献率大小依次为：煤烟尘和工业粉尘50.39%,自然源34.37%和机动车尾气15.24%。     

LIGNIN SEPARATION BY CONTINUOUS ION FLOTATION: INVESTIGATION OF PHYSICAL OPERATIONAL PARAMETERS1

ABSTRACT: Ion flotation is the term used to describe a process in which there is an initally homogeneous solution which becomes heterogeneous after the addition of an oppositely charged surfactant due to the reaction between the surfactant and specific ion(s); thus, insoluble complexes are formed. These insoluble complexes will then attached to the bubbles passing through the solution and thus leave in the foam phase. The performance of the continuous ion flotation process for the removal of haft lignin from water was investigated intensively using liquid flow rates, gas flow rates, feed locations and solution height as operational variables. The interrelationships among these physical parameters were studied and discussed. A dimensionless operational chart was established for process control. Results demonstrate that ion flotation is an effective process for removing lignin from water, provided that a quaternary ammonium salt, such as cetyldimethylbenzyl-ammonium chloride or the like, is used as a collector. At optimum operational conditions, higher than 0.95 fractional removal of lignin can be achieved.     

Comparative analysis of the street generation of inorganic urban solid waste (IUSW) in two neighborhoods of Mexico City

Inorganic urban solid waste (IUSW) is a serious problem in developing countries, and IUSW in the street that does not have adequate final disposal is responsible for serious environmental effects. The aim of this work was to determine the dynamics of the generation of IUSW in the streets of two neighborhoods of different socioeconomic strata in Mexico City during 5 weeks in 2006. The amount of IUSW was recorded every day from 9:00 to 12:00 h, separated, classified, and registered. It was found that plastic (50%) and paper (44.5%) wastes were found most frequently, whereas, textiles (0.4%) and glass (0.5%) wastes were present less frequently in all samples. The IUSWs without commercial brands were more abundant. Branded plastic wrappers of PepsiCo and Bimbo, as well as polyethylene terephthalate (PET) containers of Coca Cola, registered the highest values, while Gatorade, Barrilitos, and Peñafiel registered the lowest. The neighborhood with a higher income and more vegetation on sidewalks or in jardinières, which are used to hide solid waste, had more IUSW than the neighborhood with lower income, where IUSW was thrown out directly into the street. The knowledge of the real generation and composition of IUSW will contribute to the prevention of its negative environmental and social impacts, as well as guarantee the efficiency of its sustainable management.     

Exposure to butylated hydroxytoluene compromises endometrial decidualization during early pregnancy

Environmental Science and Pollution Research - Butylated hydroxytoluene (BHT), one of the most widely used synthetic phenolic antioxidants, is a popular food additive. Previous studies have...     

汶川地震重灾区陇南寨子崖危岩体稳定性分析与防治对策

汶川地震诱发了大量的次生地质灾害,陇南寨子崖危岩体在地震过程中发生了较大规模的崩塌,震后局部崩塌不断,严重威胁着灾后重建安置点数百人的生命安全,因此准确判断该危岩体稳定性,并采取相应的处理措施尤为重要。在研究寨子崖危岩体所处地质环境及危岩失稳的诱发因素基础上,分析了该危岩体的分布规律及形态特征,并采用工程地质分析法和极限平衡法对该区几处主要危岩单体的稳定状况进行了定性与定量分析评价。经分析判断均处于不稳定状态,需进行工程治理。针对每个危岩单体的具体特征,提出了小规模清方+锚固+SNS主动防护等的联合治理方案。     

The influence of biomass energy consumption on CO<Subscript>2</Subscript> emissions: a wavelet coherence approach

In terms of today, one may argue, throughout observations from energy literature papers, that (i) one of the main contributors of the global warming is carbon dioxide emissions, (ii) the fossil fuel energy usage greatly contributes to the carbon dioxide emissions, and (iii) the simulations from energy models attract the attention of policy makers to renewable energy as alternative energy source to mitigate the carbon dioxide emissions. Although there appears to be intensive renewable energy works in the related literature regarding renewables’ efficiency/impact on environmental quality, a researcher might still need to follow further studies to review the significance of renewables in the environment since (i) the existing seminal papers employ time series models and/or panel data models or some other statistical observation to detect the role of renewables in the environment and (ii) existing papers consider mostly aggregated renewable energy source rather than examining the major component(s) of aggregated renewables. This paper attempted to examine clearly the impact of biomass on carbon dioxide emissions in detail through time series and frequency analyses. Hence, the paper follows wavelet coherence analyses. The data covers the US monthly observations ranging from 1984:1 to 2015 for the variables of total energy carbon dioxide emissions, biomass energy consumption, coal consumption, petroleum consumption, and natural gas consumption. The paper thus, throughout wavelet coherence and wavelet partial coherence analyses, observes frequency properties as well as time series properties of relevant variables to reveal the possible significant influence of biomass usage on the emissions in the USA in both the short-term and the long-term cycles. The paper also reveals, finally, that the biomass consumption mitigates CO₂ emissions in the long run cycles after the year 2005 in the USA.