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Efficiency of a solar collector system for the public building depending on its location Full text
2020
Krawczyk, Dorota Anna | Żukowski, Mirosław | Rodero Franganillo, Antonio
Due to a technologic progress, a growth in the renewable energy markets including a high number of manufactures coming to being, the Renewable Energy Sources (RES) are both a tool for mitigating climate changes and investments that can provide direct economic profits and reduce a political or economic dependence resulting from import of fossil fuels. One of the many key solutions toward fulfilling the global increasing demand for energy and reduction of CO₂ emissions is applying solar technologies. This paper presents the results of the analysis conducted for a small public office building located in Bialystok (Poland), where solar collectors were considered as the RES for domestic hot water (DHW) system, on the understanding that existing oil boiler would be an additional source. Low values of recommended water consumption in office buildings resulted in a low energy demand. However, concerning a potential of all office governmental buildings in Poland, it would be possible to reduce CO₂ emission by 17,248 tonnes. In the comprehensive analysis, the same building in two more locations (Cordoba (Spain) and Kaunas (Lithuania)) was considered using simulation tools delivered within the framework of VIPSKILLS project as well as EnegyPlus software. The results allow to compare the mean monthly efficiency of systems or number of collectors necessary to deliver similar amount of solar energy.
Show more [+] Less [-]Determination of Pb and Mg accumulation in some of the landscape plants in shrub forms Full text
2020
Sevik, Hakan | Cetin, Mehmet | Ucun Ozel, Handan | Ozel, Halil Baris | Mossi, Mansour Mossi Mohammed | Zeren Cetin, Ilknur
Heavy metals have a separate precaution in the air pollution components as they are not easily deteriorated in nature, they tend to bioaccumulate, they are carcinogenic or poisonous, and they can be toxic even at low concentrations. Therefore, monitoring of heavy metal pollution is of great importance. Plants are frequently used as biomonitors to monitor the heavy metal pollution. However, the heavy metal accumulation capacities of plants can vary considerably depending on the plant species, as well as on the organelle basis and the amount of particulate matter in the environment. It is also very important to determine how much of the heavy metal concentrations found in plants are derived from the plant species and how much from the particulate matter on the organ. In this study, it was aimed to determine the change of heavy metal accumulation in some landscape plants grown in the city center of Kastamonu depending on plant type, plant organism, washing status, and traffic density. For this purpose, leaf and branch samples were collected from individuals of Ligustrum vulgare L., Euonymus japonica Thunb., Biota orientalis L., Juniperus sabina L., Berberis thunbergii DC, Mahonia aquifolium (Pursh) Nutt., and Buxus sempervirens L., which are frequently used in urban landscape designs growing in areas with heavy, low dense, and no traffic. Some of the collected samples were washed, and heavy metal analyses were conducted to determine the amount of Pb and Mg concentrations. It was remarkable that Pb concentration was higher in branches than in the leaves for all the species. And the alteration depending on traffic density on the base of the factors studied was in different proportion depending on the metals.
Show more [+] Less [-]Application of dairy manure as fertilizer in dry land in East China: field monitoring and model estimation of heavy metal accumulation in surface soil Full text
2020
Qian, Xiao-Yong | Shen, Gen-Xiang | Wang, Zhen-Qi | Chen, Xiao-Hua | Zhao, Qing-Jie | Bai, Yu-Jie | Tang, Zheng-Ze
Manure-based fertilizer is usually applied to agricultural soils to increase soil fertility and improve soil quality. However, this practice has an impact on the soil environment, e.g., increasing heavy metal contents. The aim of this study was to evaluate and estimate the accumulation tendencies of eight heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), manganese (Mn), and zinc (Zn) in a soil fertilized continuously with dairy manure through a 5 years’ field-scale experiment. Contents of the As, Cd, Cr, Cu, Mn, and Zn gradually increased with the fertilization time of dairy manure at the stable rate of around 326 t hm⁻² year⁻¹, leading to annual mean increases of 3.6%, 2.4%, 3.9%, 3.8%, 4.2%, and 6.1%, respectively. Based on the prediction of a dynamic mass balance model using the current practice, the contents of Cd and Zn in the fertilized soil would reach the Chinese standard values for agricultural soils in 48 and 35 years. The mitigation measures, such as lower application rates, for the environmental risk of heavy metal accumulation should be considered.
Show more [+] Less [-]Characterization and health risk assessment of organophosphate esters in indoor dust from urban and rural domestic house and college dormitory in Nanjing, China Full text
2020
Li, Dong | Zhang, Qin | Chen, Jianqiu | Zhang, Shenghu | Song, Ninghui | Xu, Huaizhou | Guo, Ruixin
Indoor dust is an important route of exposure for organophosphate esters (OPEs), which are associated with adverse health effects. In the present study, the pollution occurrence and potential health risks of 13 OPEs in indoor dust from urban homes, college dormitories, and rural homes in Nanjing were investigated. Most OPEs were detected in the tested samples. College dormitories dust samples showed significantly higher OPEs concentrations (132.31–1.61 × 10³ ng/g), followed by that in urban homes (31.42–49.84 ng/g) and rural homes (51.19–309.75 ng/g). The Mann-Whitney U test found no significant difference in the total concentrations of OPEs except for some individual OPEs between urban and rural homes. Tris (2-chloroisopropyl) phosphate (TCPP) was the most abundant compound in all tested areas. Spearman correlation coefficients and principal component analysis indicated that OPEs might originate from different sources in three microenvironments. Estimated exposures for adults and children in all indoor dust were below the relevant reference doses. Additionally, TCPP was the primary contributors to the non-carcinogenic risk, ranging from 1.07 × 10⁻⁶ to 2.20 × 10⁻⁵. Tris (2,3-dibromopropyl) phosphate was the dominant carcinogenic risk contributor in indoor dust, with a range of 1.33 × 10⁻¹¹ to 8.74 × 10⁻¹⁰. These results suggested that the health risk of OPEs was within acceptable limits in the tested areas.
Show more [+] Less [-]Fucoidan alleviates microcystin-LR-induced hepatic, renal, and cardiac oxidative stress and inflammatory injuries in mice Full text
2020
AlKahtane, Abdullah A. | Abushouk, Abdelrahman Ibrahim | Mohammed, Eman T. | ALNasser, Moonerah | Alarifi, Saud | Ali, Daoud | Alessia, Mohammed S. | Almeer, Rafa S. | AlBasher, Gadah | Alkahtani, Saad | Aleya, Lotfi | Abdel-Daim, Mohamed M.
Fucoidans (FUCs) are sulfated polysaccharides that have a wide range of bioactivities. The current study was designed to evaluate the antioxidant potential of FUC against microcystin-LR (MC-LR)-induced toxicity. Five mice groups (n = 8) were used. Group 1 received saline, Group 2 received oral FUC 100 mg/kg/day for 21 days, Group 3 received i.p. MC-LR 10 μg/kg/day for 14 days, Group 4 received MC-LR plus FUC 50 mg/kg/day, and Group 5 received MC-LR plus FUC 100 mg/kg/day. The present study showed that MC-LR administration was associated with significant increases (p < 0.01) in serum concentrations of hepatic (aspartate transferase, alanine transferase, and alkaline phosphatase), renal (urea and creatinine), and cardiac (creatine kinase and CK-MB) injury biomarkers, as well as serum lactate dehydrogenase, cholesterol, and pro-inflammatory cytokines (interleukins-1β and 6, and tumor necrosis factor-α), compared with the control group. Further, MC-LR-intoxicated mice exhibited significantly higher (p < 0.01) hepatic, renal, and cardiac tissue levels of malondialdehyde and nitric oxide, as well as lower tissue levels of reduced glutathione and activities of glutathione peroxidase, superoxide dismutase, and catalase enzymes in comparison with control mice. Treatment by FUC significantly ameliorated all the above-mentioned alterations in a dose-dependent manner with frequent restoration of the normal ranges in the FUC 100 mg/kg/day dose group. Moreover, treatment by FUC alone at 100 mg/kg/day was not associated with significant negative alterations in the assessed biochemical parameters, highlighting its safety at this dose. In conclusion, treatment by FUC significantly ameliorated organ injury, induced by MC-LR in mouse hepatic, renal, and cardiac tissues.
Show more [+] Less [-]The quantification of bisphenols and their analogues in wastewaters and surface water by an improved solid-phase extraction gas chromatography/mass spectrometry method Full text
2020
Caban, Magda | Stepnowski, Piotr
The study focused on the application of GC in the quantitative analysis of bisphenols and their analogues (12 analytes), and the improvement of solid-phase extraction for the whole water analysis of complex water samples. The role of silylation in the qualitative and quantitative analysis of bisphenols was investigated. Partial degradation occurred for selected targets during hot injection with the presence of a silylation agent. A PSA (primary and secondary amines) sorbent placed on the top of the solid-phase extraction (SPE) column sorbent was found to be a matrix component trap, mostly for humic acids. The whole water analysis was performed by washing the filters with methanol and recycling the extract to the sample. The validation of SPE-GC/MS(SIM) gave limits of detection of 1–50 ng/L for ten target bisphenols with a method recovery of between 87 and 133%. The application of the method was tested by the analysis of wastewater sampled from three wastewater treatment plants located in Poland, and municipal surface waters. The only analytes found were BPA and BPS, within the range of 16–1465 ng/L and < MDL-1249 ng/L in wastewater, and 170–3113 ng/L and < MDL-1584 ng/L in surface water, respectively.
Show more [+] Less [-]Processing and modification of hydrogel and its application in emerging contaminant adsorption and in catalyst immobilization: a review Full text
2020
Du, Hongxue | Shi, Shuyun | Liu, Wei | Teng, Honghui | Piao, Mingyue
Due to the wonderful property of hydrogels, they can provide a platform for a wide range of applications. Recently, there is a growing research interest in the development of potential hydrogel adsorbents in wastewater treatment due to their adsorption ability toward aqueous pollutants. It is important to prepare such a hydrogel that possesses appropriate robustness, adsorption capacity, and adsorption efficiency to meet the need of water treatment. In order to improve the property of hydrogels, much effort has been made by researchers to modify hydrogels, among which incorporating inorganic components into the polymeric networks is the most common method, which can reduce the product cost and simplify the preparation procedure. Not only can hydrogel be applied as adsorbent, but it also can be used as matrix for catalyst immobilization. In this review, the key advancement on the preparation and modification of hydrogels is discussed, with special emphasis on the introduction of inorganic materials into polymeric networks and consequential changes in the properties of mechanical strength, swelling, and adsorption. Besides, hydrogels used as adsorbents for removal of dyes and inorganic pollutants have been widely explored, but their use for adsorbing emerging contaminants from aqueous solution has not received much attention. Thus, this review is mainly focused on hydrogels’ application in removing emerging contaminants by adsorption. Furthermore, hydrogels can be also applied in immobilizing catalysts, such as enzyme and photocatalyst, to remove pollutants completely and avoid secondary pollution, so their progress as catalyst matrix is overviewed.
Show more [+] Less [-]Biological approaches of fluoride remediation: potential for environmental clean-up Full text
2020
Katiyar, Priya | Pandey, Neha | Sahu, Keshav Kant
Fluoride (F), anion of fluorine which is naturally present in soil and water, behaves as toxic inorganic pollutant even at lower concentration and needs immediate attention. Its interaction with flora, fauna and other forms of life, such as microbes, adversely affect various physiochemical parameters by interfering with several metabolic pathways. Conventional methods of F remediation are time-consuming, laborious and cost intensive, which renders them uneconomical for sustainable agriculture. The solution lies in cracking down this environmental contaminant by adopting economic, eco-friendly, cost-effective and modern technologies. Biological processes, viz. bioremediation involving the use of bacteria, fungi, algae and higher plants that holds promising alternative to manage F pollution, recover contaminated soil and improve vegetation. The efficiency of indigenous natural agents may be enhanced, improved and selected over the hazardous chemicals in sustainable agriculture. This review article emphasizes on various biological approaches for the remediation of F-contaminated environment, and exploring their potential applications in environmental clean-up. It further focuses on thorough systemic study of modern biotechnological approaches such as gene editing and gene manipulation techniques for enhancing the plant-microbe interactions for F degradation, drawing attention towards latest progresses in the field of microbial assisted treatment of F-contaminated ecosystems. Future research and understanding of the molecular mechanisms of F bioremediation would add on to the possibilities of the application of more competent strains showing striking results under diverse ecological conditions.
Show more [+] Less [-]Oxidative Stress and DNA methylation in male rat pups provoked by the transplacental and translactational exposure to bisphenol A Full text
2020
El Henafy, Hanan M. A. | Ibrahim, Marwa A. | Abd El Aziz, Samy A. | Gouda, Eman M.
The epigenetic changes induced by environmental contaminants play important roles in the inheritance of male reproductive dysfunction. The present study investigated DNA methylation changes and some oxidative stress biomarkers induced by bisphenol A (BPA) in male offspring. A total number of 48 female albino rats were administered orally with 50 μg/kg of BPA/day during gestation and/or lactation periods. At postnatal day 60, the samples were collected from the male pups to assess the serum testosterone, malondialdehyde (MDA) level, superoxide dismutase (SOD), glutathione S-transferase, and glutathione peroxidase (GSH-Px) activities in testicular tissue. DNA methylation in both DNA (cytosine-5)-methyltransferase 3A and estrogen receptor alpha genes was detected by methylation-specific PCR. BPA exposure resulted in significant decrease in the anogenital distance, testis and epididymis weights, serum testosterone level, SOD, GST, and GSH-Px levels with significant increase in weaning body weight and the MDA level. Additionally, BPA caused marked hypermethylation within Dnmt3A and ER- ∝ genes promoter regions in the testis of rat male pups. Graphical abstract
Show more [+] Less [-]Interaction effect of polycyclic aromatic hydrocarbon metabolites and cadmium on semen quality in nonsmokers Full text
2020
Shi, Yihao | Gaurab, Pokhrel | Wang, Wangcheng | Yan, Jianqiao | Sun, Zhongyang | Zhang, Yucong | Liu, Jihong | Liu, Xiaming | Zheng, Dan
Both cadmium (Cd) and polycyclic aromatic hydrocarbons (PAHs) are known reproductive toxicants, but their co-exposure and interaction effect on semen quality particularly in nonsmokers remain unknown. We included 333 nonsmoking men and analyzed their urine and semen samples for heavy metals and PAH metabolites. Restricted cubic spline models were used to explore the dose-response relationship between each OH-PAHs, Cd, and semen quality parameters; the generalized linear model was performed to examine the interaction of each urinary OH-PAH metabolite and Cd concentration on semen quality. Also, stratified analysis was applied to further illustrate the independent effect of PAHs on semen quality parameters in low and high concentration Cd subgroups. The dose-response and interaction effect of PAHs and Cd on male semen quality was observed. Stratified analysis in the high concentration Cd subgroup showed a negative association of 1-OHPyr concentration with semen motility. Our findings indicate that Cd not only modifies the association between PAHs and semen quality but can also exacerbate the toxic effect of pyrene on semen quality parameters. However, further studies with larger samples are needed to confirm the findings.
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