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2.
Wind tunnel tests were conducted to show that the 2.5 times rule for the determination of a necessary height for a stack close to a building is adequate for a building whose width perpendicular to the wind direction is twice its height, but that it is unnecessarily conservative for a tall thin building. An alternative rule, called Briggs' alternative, is shown to be adequate. The study was undertaken in a meteorological wind tunnel by placing model stacks and buildings in a simulated neutral atmospheric boundary layer. Smoke was used for flow visualization and methane for quantitative concentration measurements downwind of the building. The plumes were neutrally buoyant and the stacks were placed within one building height of the building in all cases. 相似文献
3.
Environmental Science and Pollution Research - Environmental degradation is one of the main drivers of climate change. One of the most broadly accepted tools to minimize environmental degradation... 相似文献
5.
The interaction between green finance and other factors, such as ecological environment, has been a research hotspot nowadays. Especially, the reasonable guiding of capital into energy conservation and environmental protection industries would greatly affect those factors, so as to the relation between them. This paper aimed to analyze the relationships between green finance, technological progress, and ecological performance quantitatively. The entropy method was used to respectively construct the system of index for green finance and technological progress, and index for ecological performance was measured by the super-SBM model. The panel vector autoregressive (PVAR) model was selected to empirically analyze dynamic relationships based on datasets from 30 provinces in China during 2008–2019 period. The results told that (1) from 2008 to 2019, China’s overall level of green finance, technological progress and ecological performance increased to varying degrees. Spatially, the areas with high-developed green finance greatly coincided with those such as large cities or the eastern coast that had good financial development. The distribution of technological progress index were similar, except some underdeveloped areas with relatively advanced scientific research institutes. The ecological performance, however, was high in the South and low in the north. (2) In the lag for 3 years, the influence of green finance on ecological performance in different regions was all positive for that all the coefficient symbols that passed the significance test were above 0, while that on technological progress was negative first and then positive. And the effects of technological progress on ecological performance were positive in ecological regions and negative in low ecological regions (0.0893 and -0.1211 in the case of three-stage lag respectively). (3) The contribution of green finance to ecological performance was high according to the results of variance decomposition, maintained at about 30%, and that of technological progress increased year by year (from 0.000 to 0.039). Therefore, we proposed to strengthen the development of green finance in underdeveloped regions. The emphasis should be laid on the researches and applications of green technology, the formulation of financing policies in innovation compensation and the establishment of a dynamic monitoring system for the ecological environment. 相似文献
6.
Present standardized methods (ASME Power Test Code 27, Western Precipitation Bulletin 50, etc.) of stack sampling usually stress sampling under conditions of steady flow (no variation with time) in order to obtain data representative of the source emissions. On many occasions these standardized methods are applied when the velocity and/or the mass flow rate of pollutants do vary with time, thus impairing the accuracy of the sampling results. In addition, it is difficult to evaluate any inaccuracy of the sampling data. This paper classifies these two source variables into four categories and suggests basic sampling approaches for each type of source condition. Several standardized procedures are evaluated and classified according to the source conditions to which the procedure is applicable. The intent of this paper is to show the most accurate sampling approach for each source condition and thus serve as a guide when planning source sampling programs. 相似文献
7.
As China’s economy began transitioning from one focused on high-speed growth to one focusing on high-quality development, sustainable green development has become the main goal pursued by the government. This study empirically measures the marginal impact of per capita GDP, technological innovation level, industrial structure, openness, fiscal decentralization, and urbanization level on per capita wastewater discharge in 11 provinces (cities) along the Yangtze River Economic Belt (YREB) from 2008 to 2018 using a quantile model. The key findings were as follows: (1) factors such as the per capita GDP, industrial structure, foreign direct investment, and urbanization in the YREB significantly increased water resource pollution; (2) the quantile model regression results showed that the relationship between economic growth and ecological pollution followed the so-called environmental Kuznets inverted U-curve. Wastewater discharge per capita was low in areas with low per capita GDP, meaning that the ecological environment in these areas was more fragile and that the environmental pollution costs due to economic growth were therefore relatively much higher in these areas; (3) fiscal decentralization significantly reduced water resource pollution in relatively developed areas although the effects in the relatively developing areas were not significant; and (4) the effects of technological innovation on reducing water resource pollution in the YREB were positive but not very significant. The results also confirmed that traditional patterns of economic growth increased water pollution in the YREB. For this reason, the government needs to urgently improve policies—for example, upgrading economic structures, preventing over-urbanization, speeding up technological innovation, introducing environmentally friendly foreign investment, and providing more rewards to best practitioners of environmental governance—that is conducive to the achievement of green ecological development. 相似文献
8.
Green infrastructure (GI) and ecosystem services (ES) are promoted as concepts that have potential to improve environmental planning in urban areas based on a more holistic understanding of the complex interrelations and dynamics of social–ecological systems. However, the scientific discourses around both concepts still lack application-oriented frameworks that consider such a holistic perspective and are suitable to mainstream GI and ES in planning practice. This literature review explores how multifunctionality as one important principle of GI planning can be operationalized by approaches developed and tested in ES research. Specifically, approaches developed in ES research can help to assess the integrity of GI networks, balance ES supply and demand, and consider trade-offs. A conceptual framework for the assessment of multifunctionality from a social–ecological perspective is proposed that can inform the design of planning processes and support stronger exchange between GI and ES research. 相似文献
9.
Background and aim The biosorption of Basic Violet 5BN (BV) and Basic Green (BG) by waste brewery’s yeast (WBY) from single and binary systems
was investigated. 相似文献
10.
Data from well-designed experiments provide the strongest evidence of causation in biodiversity studies. However, for many species the collection of these data is not scalable to the spatial and temporal extents required to understand patterns at the population level. Only data collected from citizen science projects can gather sufficient quantities of data, but data collected from volunteers are inherently noisy and heterogeneous. Here we describe a ‘Big Data’ approach to improve the data quality in eBird, a global citizen science project that gathers bird observations. First, eBird’s data submission design ensures that all data meet high standards of completeness and accuracy. Second, we take a ‘sensor calibration’ approach to measure individual variation in eBird participant’s ability to detect and identify birds. Third, we use species distribution models to fill in data gaps. Finally, we provide examples of novel analyses exploring population-level patterns in bird distributions. 相似文献
11.
The simulation of a line source of aerosol by a moving-point source is set within a mathematical framework that combines characteristics of the boundary-layer turbulence and of the moving source. Comparison of theory with experimental observation shows (i) that a moving source can simulate a true line source and (ii) that the variability in measurements is substantially as predicted by the theory. By regarding a line source as the limiting case of a moving-point source with a very small period of traverse, an expression is derived for the variability in measurements downwind of a true line source. 相似文献
12.
Environmental Science and Pollution Research - A solar pond is a simple system that collects and stores heat for thermal and electrical applications. Heat storage and heat extraction are the key... 相似文献
13.
A grassland formation has been subjected to pollution generated by the Ventanas copper smelter since 1964 (Puchuncaví Valley, central zone of Chile) with extensive damage to local vegetation and important changes in soil characteristics. The aims of the study were (1) to detect soil parameters that best explain changes observed in plant species richness and abundance and (2) to determine if pollution-derived stresses have also affected regeneration capabilities of plant communities from the soil seed bank. The grassland was quantitatively analysed in terms of physicochemical soil characteristics, plant species diversity and abundance, and soil seed bank species composition and abundance. Results showed that a decrease in total soil nitrogen explained 13% of the changes detected in plant abundance while soil pH and 0.05 M EDTA extractable copper explained 10% and 7%, respectively, of the vegetation change. It was also found that the pollution has already affected plant species regeneration capabilities from the soil seed bank and the microsite distribution of the seeds in soils. 相似文献
14.
Soil contamination with anthropogenic metals resulting from biosolid application is widespread around the world. To better predict the environmental fate and mobility of contaminants, it is critical to study the capacity of biosolid-amended soils to retain and release metals. In this paper, nickel adsorption onto a calcareous soil, a lime-stabilized biosolid, and soil–biosolid mixtures (30, 75, and 150 t biosolid/ha) was studied in batch experiments. Sorption experiments showed that (1) Ni adsorption was higher onto the biosolid than the calcareous soil, and (2) biosolid acted as an adsorbent in the biosolid–soil mixtures by increasing Ni retention capacity. The sorption tests were complemented with the estimation of Ni adsorption reversibility by successive applications of extraction solutions with water, calcium (100 mg/L), and oxalic acid (equivalent to 100 mg carbon/L). It has been shown that Ni desorption rates in soil and biosolid-amended soils were lower than 30 % whatever the chemical reagent, indicating that Ni was strongly adsorbed on the different systems. This adsorption/desorption hysteresis effect was particularly significant at the highest biosolid concentration (150 t/ha). Finally, an adsorption empirical model was used to estimate the maximum permissible biosolid application rate using French national guideline. It has been shown that desorption effects should be quantitatively considered to estimate relevant biosolid loadings. 相似文献
15.
Environmental Science and Pollution Research - We used a green sol–gel synthesis method to fabricate a novel nanoporous copper aluminosilicate (CAS) material. Nanoporous CAS was characterized... 相似文献
16.
Purpose Industrial wastewater flow caused operational difficulties in the wastewater treatment plant in Debrecen, Hungary. Bioaugmentation
was successfully applied to maintain effluent quality in the periods when wastewater of high starch content was accepted,
but, at the end of 2008, the nitrification capacity of the plant decreased considerably due to improperly pre-treated pharmaceutical
wastewater. 相似文献
17.
比较了研磨法和超声法测定浮游植物叶绿素a结果表明,丙酮一超声法对浮游植物叶绿素a的萃取效率优于研磨法,人为误差小、精密度较高、且简便安全。 相似文献
18.
Demand for green energy production is arising all over the world. A lot of emphasis is laid in making the buildings green. Even a small amount of energy savings made contribute to saving the environment. In this study, an idea is proposed and studied to extract power from the high head water in the pipelines of a building. A building of height 15 m is considered for this study. Water flowing in the pipe has sufficient energy to run a micro hydro turbine. The feasibility of producing electrical energy from the energy of pipe water is found. The motivation is to find the feasibility of generating power using a low-cost turbine. The experimental setup consists of micro turbine of 135 mm diameter coupled to a 12-V DC generator; LEDs and resistors are employed to validate the results. The theoretical calculations were presented using the fundamental equations of fluid mechanics. The theoretical results are validated using experimental and numerical results using CFD simulation. In addition, exergy analysis has been carried out to quantify the irreversibilities during the process in the system. 相似文献
19.
Reactions of lead sorption onto soil are largely affected by properties and composition of soil and its solution. In this study, the lead sorption onto regosol eutric soil from Francisco I. Madero, Zacatecas, Mexico is evaluated at different pH values. Soil samples were suspended in lead solutions of 10, 25, 50, 100, 150, 200, 300, and 400 mg/l (as Pb(NO3)2). The pH was adjusted at 2, 3, 4, and 5.5 with nitric acid for each of the lead solution concentrations. In all the cases the ionic strength was I=0.09 M with calcium nitrate. The solid-liquid-ratios were fixed in 1:100 and 1:200 g/ml. The results show that lead sorption increases when pH increases. Experimental isotherms were adjusted by both Langmuir and Freundlich models. The Langmuir affinity parameter, K, indicates that the lead sorption capacity of Francisco I. Madero soils is largely perceptible to pH changes. 相似文献
20.
Due to the increasing concerns on global warming, scarce land for agriculture, and contamination impacts on human health, biochar application is being considered as one of the possible measures for carbon sequestration, promoting higher crop yield and contamination remediation. Significant amount of researches focusing on these three aspects have been conducted during recent years. Biochar as a soil amendment is effective in promoting plant performance and sustainability, by enhancing nutrient bioavailability, contaminants immobilization, and microbial activities. The features of biochar in changing soil physical and biochemical properties are essential in affecting the sustainability of an ecosystem. Most studies showed positive results and considered biochar application as an effective and promising measure for above-mentioned interests. Bio-engineered man-made filled slope and landfill slope increasingly draw the attention of geologists and geotechnical engineers. With increasing number of filled slopes, sustainability, low maintenance, and stability are the major concerns. Biochar as a soil amendment changes the key factors and parameters in ecology (plant development, soil microbial community, nutrient/contaminant cycling, etc.) and slope engineering (soil weight, internal friction angle and cohesion, etc.). This paper reviews the studies on the production, physical and biochemical properties of biochar and suggests the potential areas requiring study in balancing ecology and man-made filled slope and landfill cover engineering. Biochar-amended soil should be considered as a new type of soil in terms of soil mechanics. Biochar performance depends on soil and biochar type which imposes challenges to generalize the research outcomes. Aging process and ecotoxicity studies of biochar are strongly required. 相似文献
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