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371.
Analyzing determinants that influence polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran(PCDD/F) emissions is helpful for decision-makers to find effective and efficient ways to mitigate PCDD/F emissions. The PCDD/F emissions and the contributions of the scale effect, structure effect and technology effect to emissions from eight main industrial sectors in2006, 2008 and 2010 in Shandong Province, were calculated in this article. Total PCDD/F emissions in Shandong increased by 52.8% in 2008(614.1 g I-TEQ) and 49.7% in 2010(601.8 g I-TEQ) based on 2006(401.9 g I-TEQ). According to the decomposition method, the largest influencing factor on PCDD/F emission changes was the composition effect(contributed 43.4%in 2008 and 120.6% in 2010 based on 2006), which was also an emission-increasing factor.In this case, the present industrial restructuring policy should be adjusted to control the proportion of production capacities with high emission factors, such as iron ore sintering and steelmaking and the secondary non-ferrous metal sector. The scale effect increased the emissions in 2008(contributed 21.9%) and decreased the emissions in 2010(contributed-28.0%). However, as a source control measure, the excess capacity control policy indeed had a significant role in emission reduction. The main reason for the technology effect(contributed 34.7% in 2008 and 7.4% in 2010 based on 2006) having an emission-increasing role was the weakness in implementing policies for restricting industries with outdated facilities. Some specific suggestions were proposed on PCDD/F reduction for local administrators at the end.  相似文献   
372.
Working along forest edges, we aimed to determine how some caterpillars can co-exist with territorially dominant arboreal ants (TDAAs) in tropical Africa. We recorded caterpillars from 22 lepidopteran species living in the presence of five TDAA species. Among the defoliator and/or nectarivorous caterpillars that live on tree foliage, the Pyralidae and Nymphalidae use their silk to protect themselves from ant attacks. The Notodontidae and lycaenid Polyommatinae and Theclinae live in direct contact with ants; the Theclinae even reward ants with abundant secretions from their Newcomer gland. Lichen feeders (lycaenid; Poritiinae), protected by long bristles, also live among ants. Some lycaenid Miletinae caterpillars feed on ant-attended membracids, including in the shelters where the ants attend them; Lachnocnema caterpillars use their forelegs to obtain trophallaxis from their host ants. Caterpillars from other species live inside weaver ant nests. Those of the genus Euliphyra (Miletinae) feed on ant prey and brood and can obtain trophallaxis, while those from an Eberidae species only prey on host ant eggs. Eublemma albifascia (Erebidae) caterpillars use their thoracic legs to obtain trophallaxis and trophic eggs from ants. Through transfer bioassays of last instars, we noted that herbivorous caterpillars living in contact with ants were always accepted by alien conspecific ants; this is likely due to an intrinsic appeasing odor. Yet, caterpillars living in ant shelters or ant nests probably acquire cues from their host colonies because they were considered aliens and killed. We conclude that co-evolution with ants occurred similarly in the Heterocera and Rhopalocera.  相似文献   
373.
China’s 2007 Open Government Information Regulations is widely considered as a milestone in the country’s information policy history and is praised as a “sunshine program”. The Environmental Information Disclosure Decree was the first to operationalize these general regulations into a sectoral information disclosure system on environment. This study assessed the implementation of the environmental information disclosure system about six months after the Decree took e ect on May 1, 2008. Through reviewing the websites of all 31 provincial Environmental Protection Bureaus and the Ministry of Environmental Protection, conducting an experiment with actual information disclosure request, and through interviews with all provincial Environmental Protection Bureaus, this article concluded that the implementation of the environmental information disclosure system still falls short. Future improvements should focus on further publicity of the regulations and decree to enhance public participation, the establishment of an independent evaluation and supervision system for information disclosure, the exchange of experiences and best practices among provincial Environmental Protection Bureaus, and on strengthening the legal status of environmental information disclosure.  相似文献   
374.
The photocatalytic activity of Fe-doped TiO2 nanoparticles is significantly increased by an acid-treatment process. The photocatalyst nanoparticles were prepared using sol–gel method with 0.5 mol% ratio of Fe:Ti in acidic pH of 3. The nanoparticles were structurally characterized by means of X-ray diffraction(XRD), high-resolution transmission electron microscope(HRTEM), energy-dispersive X-ray spectroscopy(EDX), X-ray photoelectron spectroscopy(XPS) and diffuse reflectance spectroscopy(DRS). It was observed that the photocatalytic activity suffered from an iron oxide contaminating layer deposited on the surface of the nanoparticles. This contamination layer was removed using an HCl acidtreatment process. The photocatalytic activity using 500 mg/L of Fe0.5-TiO2 in a 10 mg/L of phenol solution increased significantly from 33% to 57%(about 73% increase in the performance), within 90 min of reaction time under visible light irradiation. This significant improvement was achieved by removing the iron oxide contamination layer from the surface of the nanoparticles and adjusting p H to mild acidic and basic pHs.  相似文献   
375.
A series of investigations were conducted using sequencing batch biofilm reactor(SBBR) to explore the influence of C:N:P ratio on biological dephosphatation including the denitrifying dephosphatation and the denitrification process.Biomass in the reactor occurred mainly in the form of a biofilm attached to completely submerged disks.Acetic acid was used as the source of organic carbon.C:N:P ratios have had a significant effect on the profiles of phosphate release and phosphate uptake and nitrogen removal.The highest rates of phosphate release and phosphate uptake were recorded at the C:N:P ratio of 140:70:7.The C:N ratio of 2.5:1 ensured complete denitrification.The highest rate of denitrification was achieved at the C:N:P ratio of 140:35:7.The increase of nitrogen load caused an increase in phosphates removal until a ratio C:N:P of 140:140:7.Bacteria of the biofilm exposed to alternate conditions of mixing and aeration exhibited enhanced intracellular accumulation of polyphosphates.Also,the structure of the biofilm encouraged anaerobic–aerobic as well as anoxic–anaerobic and absolutely anaerobic conditions in a SBBR.These heterogeneous conditions in the presence of nitrates may be a significant factor determining the promotion of denitrifying polyphosphate accumulating organism(DNPAO) development.  相似文献   
376.

The tannery industries generate a solid waste known as tannery sludge, which is composed of organic and inorganic compounds, mainly chromium (Cr). When Cr is not removed from the tannery sludge, this solid waste is metal-rich and its application could affect the soil microorganisms. Alternatively, the composting of the tannery sludge can contribute to decreasing the concentration of Cr in the composted tannery sludge (CTS). However, in some cases, the concentration of Cr remains high in the CTS. During the last 10 years, the Cr-rich CTS has been successively applied in the soil, and its effect on soil microbial properties was verified. Here, we discuss the effect of successive applications of Cr-rich CTS on soil microbes. Interestingly, the findings have shown that successive applications of Cr-rich CTS selected specific soil microbial groups with potential functions. In addition, the studies added a new focus to further research evaluating the potential effect of successive applications of Cr-rich CTS on the rare microbial community.

  相似文献   
377.
This paper considers the modeling and forecasting of daily maximum hourly ozone concentrations in Laranjeiras, Serra, Brazil, through dynamic regression models. In order to take into account the natural skewness and heavy-tailness of the data, a linear regression model with autoregressive errors and innovations following a member of the family of scale mixture of skew-normal distributions was considered. Pollutants and meteorological variables were considered as predictors, along with some deterministic factors, namely week-days and seasons. The Oceanic Niño Index was also considered as a predictor. The estimated model was able to explain satisfactorily well the correlation structure of the ozone time series. An out-of-sample forecast study was also performed. The skew-normal and skew-t models displayed quite competitive point forecasts compared to the similar model with gaussian innovations. On the other hand, in terms of forecast intervals, the skewed models presented much better performance with more accurate prediction intervals. These findings were empirically corroborated by a forecast Monte Carlo experiment.  相似文献   
378.
A disaster referred to by the press as the ‘UK flooding crisis’ occurred between December 2015 and January 2016. This study employed three different levels of analysis to identify a multidimensional perspective adopted in the disaster reporting of the British Broadcasting Corporation (BBC). These levels revealed details about the social actors and their interactions. The set of news exposed diverse viewpoints on the crisis, from loss and damage to distinct affected subgroups to the various social engagement actions of aid and the multiplicity of technical response measures. The conclusions highlight considerable social amplitude in the BBC's coverage; however, owing to the reductionist approach of this media communicator, the field of action involving different social actors was not very clear in the content of the news, particularly with regard to cohesion, conflict/obstruction, and concernthe concept of crisis in its essence. In addition, the paper suggests new questions for future reports. 1  相似文献   
379.
Environmental Science and Pollution Research - There are increasing worldwide concerns about the negative impacts of healthcare waste generated in hospitals, especially in low- and middle-income...  相似文献   
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