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101.
Environmental Science and Pollution Research - The elimination of persistent organic pollutants (POPs) obsolete pesticides stockpiles, particularly the organochlorine pesticides (OCPs), is one of...  相似文献   
102.
Environmental Science and Pollution Research - Carbon dioxide (CO2) is mainly universal greenhouse gas associated with climate change. However, beyond CO2, some other greenhouse gases (GHGs) like...  相似文献   
103.

Road traffic accidents (RTAs) are among the life-threatening issues facing rural as well as sub-/urban communities. Several factors contribute to RTAs ranging from human to technical and natural/environmental impacts. Anthropogenic air pollution and corresponding environmental factors also increase the probability of RTAs. Current study reports the relationship of the weather conditions to RTAs. The study establishes the relevancy of different weather conditions like rainfall, temperature, fog, and wind storm with the incidences of RTAs in rural and urban settings of Vehari, Punjab—Pakistan. The results of the study showed that rainfall, severe coldness, fog, and heat conditions were directly related with the occurrence of RTAs. The percentage of RTAs which occurred due to fog, rainfall, temperature, and other weather-related factors was 34, 25, 21, and 20%, respectively. The age of the driver significantly correlated (R2?=?0.60) with RTAs; the drivers in the age group 40–60 years caused the least RTAs during their drive. Since the smaller vehicles were involved in maximum RTAs, it relates negatively (R2?=?0.82) to vehicles power. Among different vehicles motor bikes were involved in most (42%) of the reported RTAs. Therefore, during severe weather conditions, vehicles with smaller size and young drivers must be dealt with carefully while interacting (crossing, overtaking, and maneuvering) on the roads regardless of rural or urban conditions. Factors including civic sense, traffic education, vehicle size, drivers’ maturity, road conditions, and environmental impacts may be considered while designing traffic rules and traffic aware campaigns specific for developing countries such as Pakistan.

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104.
Trickle-bed air biofilters (TBABs) are suitable for treatment of hydrophilic volatile organic compounds, but they pose a challenge for hydrophobic compounds. Three laboratory-scale TBABs were used for the treatment of an airstream contaminated with different ratios of n-hexane and benzene mixtures. The ratios studied were 1:1, 2:1, and 1:3 n-hexane:benzene by volume. Each TBAB was operated at a pH of 4 and a temperature of 20 degrees C. The use of acidic-buffered nutrient solution was targeted for changing the microorganism consortium to fungi as the main biodegradation element. The experimental plan was designed to investigate the long-term performance of the TBABs with an emphasis on different mixture loading rates, removal efficiency with TBAB depth, volatile suspended solids, and carbon mass balance closure. n-Hexane loading rate was kept constant in the TBABs for comparison reasons and ranged from 4 to 22 g/(m3 x hr). Corresponding benzene loadings ranged from 4 to 43 g/(m3 x hr). Generally, benzene behavior in the TBAB was superior to that of n-hexane because of its higher solubility. n-Hexane showed improved performance in the 2:1 mixing ratio as compared with the other two ratios.  相似文献   
105.

Acknowledgment

Reviewer Acknowledgments  相似文献   
106.
In this work we applied base catalyzed transesterification to convert non-edible welted thistle oil (Carduus acanthoides) as new non-edible feedstock into biodiesel (Fatty acid methyl esters). The highest biodiesel yield of 88% was obtained using optimized reaction conditions of 70°C and 5:1 molar ratio (methanol:oil). The synthesized esters were characterize and confirmed by the application of NMR and FT-IR techniques. Gas chromatography and mass spectroscopy identified different fatty acids as palmatic acid (C16:0), oleic acid (C18:1), linoleic acid (18:2), arachidic acid (C20:0), eicosanic acid (C20:1), and erucic acid (C22:1) in the oil of welted thistle. Six corresponding methyl esters reported in welted thistle oil biodiesel includes 9-hexadecenoic acid, hexadecanoic acid, 9-octadecadienoic acid, 11-eicosanoic acid, eicosanoic acid and 13-docosenoicacid. Fuel properties, such as density @40°C Kg/L (0.8470), kinematic viscosity @ 40°C c St (4.37), flash point (95°C), cloud point (+4°C), pour point (?5°C), and sulfur contents (0.0112% wt) of the biodiesel produced were compatible with American Society for Testing and Materials D 6751 specifications.  相似文献   
107.
Environmental Science and Pollution Research - Drought stress is one of the major environmental factors responsible for reduction in crop productivity. In the present study, responses of two maize...  相似文献   
108.
Eruption of blue-green algal blooms occurs frequently in eutrophic lakes and fish ponds, with associated unpleasant odor and horrid scums. In the present study, we conducted a pre-test experiment in 3 m3 outdoor concrete ponds to determine the optimum concentration of aluminum sulfate (alum) required for reduction of the cyanobacterial blooms without negative effect on fish growth. As a consequence, 10 mg L?1 alum was named as the optimum concentration that was applied in 1000 m3 earthen fish ponds. Obtained results showed that Secchi disc values significantly increased from 10 to 24 cm after 14 days of alum application. Alum-treated ponds showed a reduction in total phytoplankton counts by 94 and 96 % compared to the corresponding controls after 10 and 14 days, respectively. Abundance of blue-green algae in the treated ponds was decreased by 98 % compared to the corresponding control after 14 days of alum application. Consequently, dissolved oxygen, pH, total phosphorus, orthophosphate, and chlorophyll “a” content declined significantly. Our study revealed that using 10 mg L?1 of alum is an effective way to control cyanobacterial blooms in eutrophic waters, especially in fish ponds, without negative effect in water quality.  相似文献   
109.
Lake Al-Asfar (Al-Hassa, Saudi Arabia) is under threat from contaminants released through human activities such as agriculture and urban and industrial developments. In the present study, histopathologic and ultrastructural changes in liver of tilapia Oreochromis niloticus were analyzed to monitor the possible impact of pollution in Al-Asfar estuary. Heavy metals such as Ni, Fe, Zn, Co, Ba, Pb, and Cd were predominant in the lake water and far exceeded the international permissible limits. In fish samples, high prevalences of preneoplastic changes (50 %) and one case of cholangiocarcinoma were revealed in liver tissues. Cytological damage in fish hepatocytes included glycogen exhaustion, deformation of nuclear envelope, heterochromatin condensation, mitochondrial degeneration, vesiculation of rough endoplasmic reticulum, augmentation of smooth endoplasmic reticulum, and lysosomal proliferation. In conclusion, the observed biomarker responses were potential indicators of health impairment or disease in field fish populations, although there was no direct proof of a simple cause–effect relationship. This is the first biological effect assessment in Lake Al-Asfar using tilapia as suitable target species.  相似文献   
110.

One of the major disadvantages of micropiles is their low lateral stiffness and flexural rigidity due to the small diameter. This limitation can be handled in current practice, by installing the micropile with inclined condition or providing a steel casing. Additional steel casings will increase the lateral load capacity of micropiles but increase the project cost as well. Thus, inclination of micropile which is relatively simple and cheap is recommended. In this paper, a comprehensive numerical analysis is conducted on the behavior of micropiled rafts installed with inclined condition under combined vertical and lateral loading. A FEM calibrated against full-scale axial and lateral field tests is used to conduct the analysis. The soil profile is soft clay soil underlain by a layer of dense sand. The study investigates the impact of several parameters which are as follows: magnitude of vertical loading, reinforcement type, inclination angle of micropiles, and number of inclined micropiles. The study reveals that increasing vertical loads causes continuous decrease in the lateral load capacity of micropiled rafts. When all micropiles installed are inclined, the positively inclined micropiles carry 79–86% of the total lateral load carried by micropiles, whereas the negatively inclined ones carry 14–21%. Inclined micropiles offer greater lateral load sharing ratio (αh) than that of vertical ones, largest at θ = 45°. The effect of micropile reinforcement on improving the lateral performance is low compared to the effect of micropile inclination angle.

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