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1.
Environmental Science and Pollution Research - The average nutrient concentrations values presented in Table 1 on page 4 in the publication have the unit mg L?1 for the mineral nutrients Fe,...  相似文献   
2.
This article postulates strong endogenous relationships in lower income countries between institutional quality, financial development and sustained economic growth. These associations were investigated using the vector-error correction model (VECM) and Granger causality method for a sample of 79 countries from 2005 to 2022. The findings show that (1) these variables reinforce each other in the short run. (2) In the long run, both institutional quality and financial development can fuel economic growth. (3) The positive effect of institutional quality on economic growth is greater than that of financial development. Policy implications of these findings are that careful attention should be paid to co-development policies to enhance the institutional quality and the financial system in these economies. Policies should also consider economic growth strategies to enable sustainable economic growth rates.  相似文献   
3.
对于水生昆虫及其它生物而言,大小是一个重要的功能性状,但是头宽的测量特别耗时和受人为因素影响.随着计算机技术的发展,基于图像分析技术(一种快速测量大小的策略)可获得传统方式难以获得的大小参数,明确这些大小参数与头宽的关系,对推动这些参数的应用具有重要意义.选择两种个体大小差异较大的蜉蝣(梧州蜉和光滑细蜉)作为研究对象,对其头宽与基于数字图像获得的面积,周长,最小矩形的长和宽,最适合椭圆的长轴和短轴和粒径等个体大小参数的相关性进行研究.数字图像采用改进后的描述仪扫描获取;图像分析基于ImageJ软件完成;基于二元直线回归和多元直线回归分析各参数之间的相关性.各种层次的回归分析结果均表明:基于图像分析获得的两种蜉蝣所有个体大小参数均与头宽大小呈极其显著的正相关性,其中面积的相关性最高.并且面积与其它大小参数相关性也极其显著,对个体大小具有较好的代表性.研究结果为推动数字图像分析技术应用在水生昆虫及其它生物的生物学和生态学研究中提供了技术支持和理论依据.  相似文献   
4.
Journal of Material Cycles and Waste Management - As resident awareness of environmental issues has grown, waste disposal has become an important part of urban environmental governance. Most...  相似文献   
5.
Flares are important safety devices for pressure relief; at the same time, flares are a significant point source for soot and highly reactive volatile organic compounds (HRVOCs). Currently, simple guidelines for flare operations to maintain high combustion efficiency (CE) remain elusive. This paper fills the gap by investigating the characteristics of the incipient smoke point (ISP), which is widely recognized as the condition for good combustion. This study characterizes the ISP in terms of 100–% combustion inefficiency (CE), percent opacity, absorbance, air assist, steam assist, air equivalence ratio, steam equivalence ratio, exit velocity, vent gas net heating value, and combustion zone net heating value. Flame lengths were calculated for buoyant and momentum-dominated plumes under calm and windy conditions at stable and neutral atmosphere. Opacity was calculated using the Beer–Lambert law based on soot concentration, flame diameter, and mass-specific extinction cross section of soot. The calculated opacity and absorbance were found to be lognormally distributed. Linear relations were established for soot yield versus absorptivity with R2 > 0.99 and power-law relations for opacity versus soot emission rate with R2 ≥ 0.97 for steam-assisted, air-assisted, and nonassisted flares. The characterized steam/air assists, combustion zone/vent gas heating values, exit velocity, steam, and air equivalence ratios for the incipient smoke point will serve as a useful guideline for efficient flare operations.

Implications: A Recent EPA rule requires an evaluation of visible emissions in terms of opacity in compliance with the standards. In this paper, visible emissions such as soot particles are characterized in terms of opacity at ISP. Since ISP is widely recognized as most efficient flare operation for high combustion efficiency (CE)/destruction efficiency (DE) with initial soot particles formed in the flame, this characterization provides a useful guideline for flare operators in the refinery, oil and gas, and chemical industries to sustain smokeless and high combustion efficiency flaring in compliance with recent EPA regulations, in addition to protecting the environment.  相似文献   

6.
Chen  Hongqiang  Lin  Lijin  Liao  Ming’an  Wang  Jin  Tang  Yi  Sun  Guochao  Liang  Dong  Xia  Hui  Deng  Qunxian  Wang  Xun  Lv  Xiulan  Ren  Wei 《Environmental science and pollution research international》2019,26(24):24474-24481
Environmental Science and Pollution Research - Grapevine (Vitis vinifera L.) intercropping with floricultural cadmium (Cd) accumulator plants (Helianthus annuus L., Cosmos sulphureus Cav., Cosmos...  相似文献   
7.
Environmental Science and Pollution Research - The effect of air staging strategies on NOx control was investigated on a 210-kW small-scale biomass boiler (SBB) and a 1.4-MW medium-scale biomass...  相似文献   
8.
Ma  Huimin  Di  Danyang  Li  Lin  Zhang  Wei  Wang  Jianmei 《Environmental geochemistry and health》2022,44(9):2905-2918
Environmental Geochemistry and Health - Effective supply of environmental public services (EPS) is important to guarantee the mitigation of residential pollution exposure risk. This study analyzes...  相似文献   
9.
Water represents 71% of all earth area and about 97% of this water is salty water. So, only 3% of the overall world water quantity is freshwater. Human can benefit only from 1% of this water and the remaining 2% freeze at both poles of earth. Therefore, it is important to preserve the freshwater through increasing the plants consuming salty water. The future prosperity of feed resources in arid and semi-arid countries depends on economic use of alternative resources that have been marginalized for long periods of time, such as halophytic plants, which are one such potential future resource. Halophyte plants can grow in high salinity water and soil and to some extent during drought. The growth of these plants depends on the contact of the salted water with plant roots as in semi-desert saline water, mangrove swamps, marshes, and seashores. Halophyte plants need high levels of sodium chloride in the soil water for growth, and the soil water must also contain high levels of salts, as sodium hydroxide or magnesium sulfate. There are many uses for halophyte plants, including feed for animals, vegetables, drugs, sand dune stabilizers, wind shelter, soil cover, wetland cultivation, laundry detergents, and paper production. This paper will focus on the use of halophytes as a feed additive for animals. In spite of the good nutritional value of halophytes, some anti-nutritional factors as nitrates, nitrite complexes, tannins, glycosides, phenolic compounds, saponins, oxalates, and alkaloids may be present in some of them. The presence of such anti-nutritional agents makes halophytes unpalatable to animals, which tends to reduce feed intake and nutrient use. Therefore, the negative effects of these plants on animal performance are the only objection against using halophytes in animal feed diets. This review article highlights the beneficial impact of considering halophytes in animal feeding on saving freshwater and illustrates its nutritive value for livestock from different aspects.  相似文献   
10.
Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.  相似文献   
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