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Effect of Disk Skimmer Material and Oil Viscosity on Oil Spill Recovery Полный текст
2021
El-Gayar, D. A. | Khodary, M. A. | Abdel-Aziz, M. H. | Khalil, M. F.
The present work aims to study the effect of disk material and disk surface roughness on the oil recovery rate and oil recovery efficiency. Materials used in this study were steel, plastic, and woven fabric; two types of oil were used, namely, SAE50 and used car engine oil. The oil recovery rate was found to increase with increasing disk rotational speed. The rate of oil recovery ranged from 88.19 to 337.14 (mL/min) for SAE50 oil and ranged from 89.03 to 355.4 (mL/ min) for used oil depending on disk rotational speed and the type of disk. The rough steel disk performance is inferior to other disks except at high rotational speeds. Oil recovery efficiency was found to decrease with increasing disk rotational speed. The oil recovery efficiency ranged from 77 to 95.2 for SAE50 oil and ranged from 72 to 95.2 for used oil depending on disk rotational speed and the type of disk. Specific energy consumption ranged from 3.08×10⁻⁴ to 4.7×10⁻⁴ kW·h/kg of recovered SAE50 oil and ranged from 3.04×10⁻⁴ to 2.589×10⁻⁴ kW·h/kg of recovered used oil depending on disk rotational speed.
Показать больше [+] Меньше [-]Could Aqueous Film-Forming Foams (AFFFs) and Encapsulator Agents (EAs) Interfere on the Reproduction and Growth of Daphnia similis? Полный текст
2021
Cara, Álison Luís | dos Santos Barboza Ortega, Andressa | Pusceddu, Fabio Hermes | de Souza Abessa, Denis Moledo | Pereira, Camilo Dias Seabra | Maranho, Luciane Alves
In firefighting of class B, fire suppression agents (FSA), such as aqueous film-forming foams (AFFF) and encapsulating agents (EA), have been used to cool, suppress, and remove the burning surface. However, several studies pointed out the aquatic environment as the destination of perfluorinated compounds and their degradation products. The toxicity of per- and polyfluoroalkyl compounds (PFASs), especially the FSAs, raises environmental health concerns. In this study, the reproduction and body length of the aquatic microcrustaceans Daphnia similis were analyzed through the organisms’ exposure to two FSAs (Cold Fire® Suppressant Agent and Liovac®) in the following dilutions: 0.000093%, 0.0001875%, 0.000375%, 0.00075%, 0.0015%, 0.0003125%, 0.000625%, 0.01025%, 0.025%, and 0.005%, respectively. Our results showed that exposure to FSA caused inhibitory effects on the reproduction of Daphnia similis. The LOEC and NOEC of Cold Fire® were respectively 0.0001875% and 0.000093%, and significant chronic toxicity (p < 0.05) was observed at 0.0015 to 0.0001875% concentrations. The mean body lengths of surviving organisms exposed to all dilutions of Cold Fire® were significantly lower (p < 0.05) than the control organisms. For Liovac®, the respective LOEC and NOEC were 0.005% and 0.0025%. No significant differences were observed (p < 0.05) in the length of the organisms exposed to the Liovac®, compared to the control. The adverse effects on D. similis were observed at concentrations lower than those recommended by the manufacturers. Our results show that FSAs may cause chronic toxicity to freshwater aquatic organisms, posing risk in a real environmental scenario.
Показать больше [+] Меньше [-]The conversion of the nutrient condition alter the phenol degradation pathway by Rhodococcus biphenylivorans B403: A comparative transcriptomic and proteomic approach Полный текст
2021
Xie, Xiaohang | Liu, Jiashu | Jiang, Zhengbing | Li, Huanan | Ye, Meng | Pan, Hong | Zhu, Jingwei | Song, Huiting
Highly toxic phenol causes a threat to the ecosystem and human body. The development of bioremediation is a crucial issue in environmental protection. Herein, Rhodococcus biphenylivorans B403, which was isolated from the activated sludge of the sewage treatment plant, exhibited a good tolerance and removal efficiency to phenol. The degradation efficiency of phenol increased up to 62.27% in the oligotrophic inorganic medium (MM) containing 500-mg/L phenol at 18 h. R. biphenylivorans B403 cultured in the MM medium showed a higher phenol degradation efficiency than that in the eutrophic LB medium. On the basis of the transcriptomic and proteomic analysis, a total of 799 genes and 123 proteins showed significantly differential expression between two different culture conditions, especially involved in phenol degradation, carbon metabolism, and nitrogen metabolism. R. biphenylivorans B403 could alter the phenol degradation pathway by facing different culture conditions. During the phenol removal in the oligotrophic inorganic medium, muconate cycloisomerase, acetyl-CoA acyltransferase, and catechol 1,2-dioxygenase in the ortho-pathway for phenol degradation showed upregulation compared with those in the eutrophic organic medium. Our study provides novel insights into the possible pathway underlying the response of bacterium to environmental stress for phenol degradation.
Показать больше [+] Меньше [-]LncRNA PTTG3P induced aberrant glycosylated IgA1 production and B cell growth in IgA nephropathy Полный текст
2021
Bi, Min | Shi, Jie | Zhao, Yu | Li, Chunmei
Growing evidences suggested that lncRNAs played functional role in several cell functions such as cell growth, invasion, migration, metabolize, apoptosis, and differentiation. However, roles of lncRNA in the development and progression of IgAN remain unknown. In this reference, we indicated that PTTG3P level was overexpressed in IgAN samples compared to healthy subject. PTTG3P expression was also higher in urinary of IgAN cases than in urinary of healthy control. Furthermore, the urinary expression of PTTG3P was correlated with PTTG3P expression in intra-renal of IgAN cases. PTTG3P overexpression induced B cell growth and enhanced cyclin D1 and ki-67 expression. Overexpression of PTTG3P induced IL-1β and IL-8 production. miR-383 level was decreased in IgAN samples compared to healthy subject. In addition, miR-383 expression was also lower in urinary of IgAN cases than in urinary of healthy control. Elevated miR-383 expression decreased luciferase intensity regulated with PTTG3P, while overexpression of miR-383 had no effect on luciferase intensity of the mutant PTTG3P. PTTG3P overexpression suppressed miR-383 expression in B cells. Ectopic miR-383 expression suppressed B cell growth and IL-1β and IL-8 production. Finally, we showed that overexpression of PTTG3P promoted B cell growth and IL-1β and IL-8 production via regulating miR-383. There results proved that PTTG3P played crucial role in progression of IgAN.
Показать больше [+] Меньше [-]Sorption and transport of Mn2+ in soil amended with alkali-modified pomelo biochar Полный текст
2021
An, Qiang | Zhu, Sheng | Li, Zheng | Deng, Shuman | Zhao, Bin | Meng, Fanyu | Jin, Ningjie | Ren, Xiaozhou
Owing to its effectiveness and being environment-friendly, biochar has been used for adsorbing and immobilizing pollutants in soil in recent years of studies, which is also suitable for manganese pollution in soil caused by manganese mining and processing activities. In this research, alkali-modified pomelo biochar (MBC) was regarded as a soil amendment, and the improvement of soil physicochemical properties and Mn²⁺ sorption and transport in soil by modifying with MBC were investigated. In incubation experiment, 0–10% (w/w) MBC addition amount significantly improved the physicochemical properties of soil. Due to the amelioration of soil physicochemical properties along with the oxygen-containing functional groups and the developed pore structure of MBC itself, the adsorption capacity of MBC modification soil towards Mn²⁺ (qₑ) was enhanced in batch adsorption experiment, and qₑ increased by 10–108% when MBC ratio grew from 0 to 10% at 300 mg·L⁻¹ Mn²⁺ solution. In column transport experiment, the Mn²⁺ retention rate climbed by 13–106% from 0 to 10% MBC addition proportion when adopted the MBC filling way that placed MBC on the soil upper layer, and the reinforced restriction on Mn²⁺ transport in soil amended with MBC might ascribe to the enhanced qₑ as well as the reduced saturated hydraulic conductivity. These results proved that MBC effectively augmented adsorption ability and suppressed transport of Mn²⁺ in soil, which could provide an available mind on prevention and remediation of soil Mn contamination.
Показать больше [+] Меньше [-]Survival Strategies in Khavi Grass [Cymbopogon jwarancusa (Jones) Schult.] Colonizing Hot Hypersaline and Arid Environments Полный текст
2021
Fatima, Sana | Hameed, Mansoor | Naz, Nargis | Shah, Syed Mohsan Raza | Naseer, Mehwish | Ahmad, M. S. A. (Muhammad Sajid Aqeel) | Ashraf, Muheammad | Ahmad, Farooq | Khalil, Sangam | Ahmad, Iftikhar
Deserts are generally prone to a number of ecological hazards which act as agents for the development of particularly a very diverse group of grasses, which can resist to salt stress through multiple morpho-anatomical and physio-biochemical mechanisms. Of such grasses, Cymbopogon jwarancusa is found inhabiting different saline patches of the Cholistan desert, so its different populations were selected from five saline habitats [least saline Derawar Fort (DF); moderately saline Trawaywala Toba (TW) and Bailahwala Dahar (BD), and high saline Ladam Sir (LS) and Pati Sir (PS)] and tested for their salt tolerance mechanism. Differentially adapted populations of this grass showed specific modifications in terms of anatomical features, mainly increased sclerification in both external hypodermis and internal endodermis, cortical layers, and increased size of xylem vessels with increase in salinity of the habitat. Increased endodermal thickness may control radial movement of water in roots. The reduction in leaf area is found to be the principal strategy that makes C. jwarancusa promising to attenuate the effects of the reduced availability of water under saline stress. Thick epidermis with dense cuticle and large bulliform cells area can be particularly considered as an important adaptation of this grass against physiological drought. Moreover, increased density of trichomes is found critical for checking undue water loss through the leaf surface and increase in these tissues at high salinity level may indicate that this species has better adapted to saline habitat.
Показать больше [+] Меньше [-]The environmental sustainability effects of financial development and urbanization in Latin American countries Полный текст
2021
Adebayo, Tomiwa Sunday | Ramẓān, Muḥammad | Iqbal, Hafiz Arslan | Awosusi, Abraham Ayobamiji | Akinsola, Gbenga Daniel
The present study assesses the impact of urbanization, economic growth, energy consumption, and financial development on CO₂ emissions in Latin American countries using a dataset spanning between 1980 and 2017. The current paper employs utilized panel econometric techniques such as CIDF, panel unit test, the Westerlund panel cointegration, fully modified ordinary least squares (FMOLS), dynamic ordinary least squares (DOLS), and Dumitrescu Hurlin panel causality test to assess these associations. The outcomes from the FMOLS and DOLS estimation reveal that (i) economic growth impacts CO₂ emissions positively, (ii) energy consumption exerts a positive impact on CO₂ emissions, and (iii) urbanization impacts CO₂ emissions positively. Furthermore, the outcomes of the causality test reveal that energy consumption and economic growth can predict CO₂ emissions in Latin countries. The findings highlight the importance of policymakers actively coordinating strategies to address Latin America’s severe environmental degradation.
Показать больше [+] Меньше [-]Exposure to phthalates and cardiovascular diseases in Chinese with type 2 diabetes Полный текст
2021
Zhang, Haojie | Chen, Jingsi | Chen, Chi | Wan, Heng | Chen, Yi | Wang, Yuying | Zhang, Wen | Chen, Bo | Wang, Ningjian | Lu, Yingli
Cardiovascular disease (CVD) results in more than half of the mortality and the majority of morbidity in patients with type 2 diabetes. We aim to evaluate the associations of urinary concentrations of phthalate metabolites with CVD in diabetic patients and explore whether CVD risk factors mediate or interact with these associations. A total of 675 type 2 diabetic participants were enrolled from Shanghai, China, in 2018. CVD was defined as a self-reported diagnosis by a physician including coronary heart disease, myocardial infarction, or stroke; it was further reconfirmed in the records from the registration platform. Ten phthalate metabolites were measured in urine. We found positive associations were found among the level of monoethyl phthalate and monoisobutyl phthalate and CVD (OR 1.138, 95% CI 1.032, 1.254; OR 1.369, 95% CI 1.049, 1.786, respectively). Monoisobutyl phthalate and monobenzyl phthalate were marginally and positively associated with carotid intima-media thickness and common carotid artery diameter, respectively. None of the CVD risk factors, including HOMA-IR, body mass index, lipid profile, or blood pressure, significantly mediated the association between the metabolites and CVD. The conditional indirect effect on CVD was significantly stronger for current smoking and dyslipidemia for monoethyl phthalate and for no statin usage and men for monoisobutyl phthalate. In conclusion, phthalate exposure was positively associated with CVD in Chinese with type 2 diabetes. Type 2 diabetic men who are currently smoking, have an uncontrolled lipid profile, and are not using statins might be more susceptible to CVD when exposed to phthalates.
Показать больше [+] Меньше [-]Lifecycle assessment of methanol production from blast furnace gas Полный текст
2021
Kang, Dongseong | Han, Jeehoon
A technological scenario configuration for producing methanol (MeOH) from blast furnace gas (BFG) with natural gas (NG)-based energy generation was evaluated by a rigorous life cycle assessment. The new BFG scenario was compared to a conventional BFG scenario—BFG energy generation with NG-based MeOH production. In all, 18 environmental impact categories were estimated for both technological BFG scenario configurations on a conceptual plant level. The results of a case study in South Korea indicated that the new BFG scenario performs better for 12 environmental impacts (20–97% lower), but fossil resource depletion is worse because NG is used for the displacement of energy generation. The robustness of the environmental impact results for the new BFG scenario was supported by a case study, which highlighted that the primary source for the displacement of energy generation is crucial.
Показать больше [+] Меньше [-]Statistical analysis and susceptibility properties of heavy/light metal pollution in surface seawater of Izmir Bay Полный текст
2021
Sabikoglu, Israfil
The inner bay of Izmir is known as the part between Sasalı/Karşıyaka coastline and Güzelbahçe/Bayraklı. It is used extensively in transportation. There is constant ferry transportation and an international port operates in this region. There are also a few streams that flow into the inner bay. Therefore, the inner bay can be exposed to continuous chemical pollutants, and these wastes can intensively be observed in its natural structure. In this study, the magnetic susceptibility values and elemental analyses of the samples taken from the surface sea waters of the inner bay coastline were performed. Silicon, strontium, and manganese elements were mostly observed in the samples. The greatest susceptibility values were seen in the Bostanlı ferry port and Göztepe ferry. In addition, the standard deviation and correlation coefficient values of the samples were calculated and discussed. According to the correlation coefficient value, it can be said that there is a positive correlation between metal ion ratios and magnetic susceptibility.
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