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Simultaneous biofiltration of H2S and NH3 using compost mixtures from lignocellulosic waste and chicken manure as packing material 全文
2021
Vela-Aparicio, Diana | Forero, Daniel F. | Hernández, Mario A. | Brandão, Pedro F. B. | Cabeza, Iván O.
Biofiltration offers an efficient and economical alternative for the elimination of offensive odors caused by hydrogen sulfide, ammonia, and volatile organic compounds. Considering that packing materials affect the performance and represent the main installation cost, the purpose of this work was to evaluate the biofiltration of H₂S and NH₃ comparing three composted mixtures made from chicken manure and lignocellulosic residues (pruning waste, sugarcane bagasse, and rice husk) used as packing material. A range of gas concentrations similar to those of a municipal WWTP was used in the biofiltration of a contaminated stream performed on a laboratory scale. The results indicate that at low concentrations of H₂S (6–36 ppm) and NH₃ (0–1 ppm), the three biofilters showed 100% removal efficiency. Now, at the maximum levels of gas concentrations of H₂S (250 ppm) and NH₃ (19 ppm) while the removal efficiency of H₂S remained higher than 90% in all cases, the removal efficiency of NH₃ remained higher than 90% only in the sugarcane bagasse biofilter. Compost mixtures with sugarcane bagasse and rice husk are highly reliable as packing material for biofiltration at high concentration of H₂S. Specifically, the sugarcane bagasse mixture had the highest removal efficiency (99% H₂S and 95% NH₃) and the highest elimination capacity (15 g H₂S/m³h and 0.6 g NH₃/m³h), making it a better option for the elimination of both gases. These results represent a contribution to the construction of a low-price elimination system of offensive odors in WTTPs and other industries.
显示更多 [+] 显示较少 [-]Elimination of pharmaceutical pollutants by solar photoelectro-Fenton process in a pilot plant 全文
2021
Bugueño-Carrasco, Sebastián | Monteil, Hélène | Toledo-Neira, Carla | Sandoval, Miguel Angel | Thiam, Abdoulaye | Salazar, Ricardo
In this study, the simultaneous degradation of antibiotics (ampicillin, sulfamethazine, and tetracycline; and non-steroidal anti-inflammatories (diclofenac and salicylic acid)) including the total organic carbon abatement by solar photoelectro-Fenton process was assessed. Eight liters of solution containing the mixture of the five pharmaceuticals in 1 mmol L⁻¹ Fe²⁺, 0.05 mol L⁻¹ Na₂SO₄ at pH 3 and 35 °C were electrolyzed applying different current densities (j = 10, 25, and 50 mA cm⁻²) in a solar-electrochemical pilot plant. The pilot plant was equipped with an electrochemical filter press cell with a dimensionally stable anode (DSA type) and an air-diffusion cathode coupled to a solar photoreactor exposed directly to sunlight radiation. All pharmaceuticals were degraded during the first 10 min. A TOC removal efficiency of 99.2% after 100 min of treatment with an energy consumption of 534.23 kW h (kgTOC)⁻¹ and 7.15 kW h m⁻³ was achieved. The pharmaceutical concentration decay followed a pseudo-first-order kinetics. The specific energy per unit of mass of ampicillin, diclofenac, salicylic acid, sulfamethazine, and tetracycline was obtained at 11.73, 19.56, 35.2, 11.73, and 39.32 kW h (kgPD)⁻¹ for ampicillin, diclofenac, salicylic acid, sulfamethazine, and tetracycline, respectively. With our results, we demonstrated that SPEF is an emerging technology for the treatment of this type of pollutants in short time.
显示更多 [+] 显示较少 [-]Sex-specific elemental accumulation and histopathology of pikeperch (Sander lucioperca) from Garaši reservoir (Serbia) with human health risk assessment 全文
2021
Nikolić, Dušan | Skorić, Stefan | Poleksić, Vesna | Rašković, Božidar
Accumulation of 26 elements (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Si, Sr, and Zn) was analyzed in the gills, liver, and muscle of pikeperch males and females from Garaši reservoir using inductively coupled plasma optical emission spectrometry (ICP-OES). Histopathological (HP) changes in the gills and liver, and human health risk were also analyzed. The gills were most affected by metal pollution in both sexes. The concentrations of Hg in muscle tissue of four males, and Cd in two females and two males exceeded the maximum allowed concentrations. Statistical tests only revealed significant differences regarding the concentrations of Mg, K, and S in the muscle (higher in males) and Al, Ag, and Mn in the liver (higher in females) of individuals between sexes. Low to moderate levels of pathological changes were recorded for the gills and liver in both sexes. Significant differences between sexes were observed for inflammatory index of gills (IGI) and HP index of gills (IG), males had higher values compared to females, and for liver necrosis, where females had higher values compared to males. Gills were less affected by HP changes compared to the liver. There was no significant non-cancerogenic and cancerogenic health risk due to the consumption of pikeperch meat from the Garaši reservoir. However, women are under greater risk by consuming the meat of both male and female individuals, probably due to a longer lifetime and lesser body weight compared to the men.
显示更多 [+] 显示较少 [-]Investigating marginal effect of economic growth on environmental quality based on six environmental indicators: does financial development have a determinative role in strengthening or weakening this effect? 全文
2021
Fakher, Hossein Ali | Panahi, Mostafa | Imāmī, Karīm | Peykarjou, Kambiz | Zeraatkish, Seyed Yaghoub
Given the complexity of the correlation of economic growth with financial development, and their interactive impacts on environmental quality, this study attempted to present new insights into indecisive outcomes from the contribution of financial development in determining the impressionability of environmental indicators under economic growth conditions. Previous studies only employed a single environmental indicator for analyzing the correlation between economic factors and environmental quality. However, six environmental indicators are adopted in this study to evaluate environmental quality and to reach major goals of this research. To this end, using 2-stage system generalized technique of moment estimator, the association of economic growth, energy consumption, financial development, environmental indicators, and trade openness is determined in selected OPEC countries for years 2010 to 2019. Findings indicated that accompanied by the effects of economic growth on any EFI, ANS, PN, and EPI variables, the financial development enhances such effect. This is while, the financial development would weaken the economic growth effect on the ESI variable. Regarding EVI, no significant association was observed. Regarding to ESI, EPI, and PN, trade openness applies a significantly positive impact on environmental quality; on the other hand, it has positive role in environmental degradation based on EFI and ANS. This is while, according to the EVI variable, trade openness has not meaningful impact on environmental status. Finally, energy use has significant and positive effects on environmental degradation in each of environmental indicators. However, this variable has not shown significant impact on EPI and ANS. Alternatively, findings indicated that financial development can be considered an important and key variable in improvement of the environmental quality due to the moderating role it plays relative to the negative economic growth effect on the environmental quality. At the end of this paper, some limitations are presented, and some suggestions for further studies are provided as well.
显示更多 [+] 显示较少 [-]Ameliorative role of Ulva extract against heavy metal mixture—induced cardiovascular through oxidative/antioxidant pathways and inflammatory biomarkers 全文
2021
Nabil-Adam, Asmaa | Shreadah, Mohamed A.
The current study investigates the therapeutic and curative effect of Ulva lactuca polyphenolic extract (ULPE) in general and particularly polyphenolics compounds against heavy metal mixture (HME). The toxicity behind heavy metal is due to oxidative stress resulted from heavy metals pollution or administration through contaminated food (vegetables, water, and fish). Heavy metal toxicity plays a major role in different cardiovascular diseases. The objective of this study is aimed to examine the protective effect of ULPE against heavy metal mixture induced cardiovascular diseases through oxidative/antioxidant and inflammatory pathways. Sixty male rats (Sprague-Dawley) were assigned to six groups. Group I served as the control, group II served as the induced group receiving subcutaneously for 7 days 0.25 mg/100 gm body weight/day heavy metal mixtures (Equal concentration of Ni, Cd, Co and Hg chloride, and Pb acetate), group III received (i.p.) ULPE of dose 30 mg for 15 days, group IV served as the protected group pretreated with ULPE for 15 days as a protection dose, and then treated with the heavy metal-mixture, group V served as protected standard group pretreated with vitamin C (VitC) (50 mg/Kg) and then treated with the heavy metal-mixture, and group VI served as standard group treated with VitC (50 mg/Kg). The main pathological changes within the heart revealed heart inflammation after heavy-metal mixtures administrations. On contrast to the protected group treated with ULPE (group IV), the protection group (group II) showed a significant increase in the antioxidant as well as anti-inflammatory biomarker. The cardiovascular biomarkers (Troponin T, CRP, and BNP) showed similar attitude elevations in induction group and decreased greatly in protection and VitC group. The antioxidant and the anti-inflammatory activities of ULPE are a consequence of their higher polyphenolic contents as well as marine secondary metabolites which are confirmed using qualitative and quantitative analysis. From the current result, we concluded that ULPE possesses a cardiovascular protective agent as a result of highly contents of different bioactive secondary metabolites which have antioxidant as well as free-radical scavenging and anti-inflammatory activates. Showed the mechanism of ULPE as cardioprotective against heavy metal mixture
显示更多 [+] 显示较少 [-]Acute effects of ambient air pollution on outpatients with chronic rhinitis in Xinxiang, China 全文
2021
Lu, Mengxue | Yang, Huijuan | Wang, Jingyao | An, Zhen | Li, Juan | Wu, Zhineng | Zhao, Qian | Li, Huijun | Zhai, Desheng | Liu, Yue | Wu, Weidong | Song, Jie
Air pollution exposure leads to increased mortality and morbidity rates of respiratory diseases. Most of the evidence was founded on acute diseases such as acute lower respiratory diseases. However, limited studies have been conducted to evaluate the effects of air pollution on chronic respiratory diseases. This time-series study was conducted to examine the acute effects of 6 criteria ambient air pollutants on hospital outpatients with chronic rhinitis (CR) in Xinxiang, China. We retrieved 223,826 outpatient records of patients with respiratory diseases, of which 62,901 were those of patients with CR. Results showed that the current 10-μg/m³ increase in fine particulate matter (PM₂.₅), inhalable particulate matter (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO) corresponds to 0.67% (95% confidence interval [CI]: 0.15–1.18%), 0.58% (95% CI: 0.24–0.92%), 1.89% (95% CI: 0.52–3.27%), 3.01% (95% CI: 1.66–4.35%), and 0.06% (95% CI: 0.03–0.10%) increments in outpatients with CR, respectively. In addition, the effects in the male were stronger than those in the female. Higher effect estimates were observed in the old (≥ 65 years of age) and younger (< 15 years of age) groups. Our study confirmed the association between air pollution and outpatients with CR in Xinxiang, China. More stringent air pollution control measures must be implemented.
显示更多 [+] 显示较少 [-]Heterologous expression and purification of keratinase from Actinomadura viridilutea DZ50: feather biodegradation and animal hide dehairing bioprocesses 全文
2021
Ben Elhoul, Mouna | Zaraî Jaouadi, Nadia | Bouacem, Khelifa | Allala, Fawzi | Rekik, Hatem | Mechri, Sondes | Khemir Ezzine, Haifa | Miled, Neila | Jaouadi, Bassem
The keratin-degrading bacterium Actinomadura viridilutea DZ50 secretes a keratinase (KERDZ) with potential industrial interest. Here, the kerDZ gene was extracellularly expressed in Escherichia coli BL21(DE3)pLysS using pTrc99A vector. The recombinant enzyme (rKERDZ) was purified and biochemically characterized. Results showed that the native and recombinant keratinases have similar biochemical characteristics. The conventional dehairing with lime and sodium sulfide degrades the hair to the extent that it cannot be recovered. Thus, these chemical processes become a major contributor to wastewater problem and create a lot of environmental concern. The complete dehairing was achieved with 2000 U/mL rKERDZ for 10 h at 40 °C. In fact, keratinase assisted dehairing entirely degraded chicken feather (45 mg) and removed wool/hair from rabbit, sheep, goat, or bovine’ hides (1.6 kg) while preserving the collagen structure. The enzymatic process is the eco-friendly option that reduces biological (BOD) (50%) and chemical (COD) oxygen demands (60%) in leather processing. Consequently, the enzymatic hair removal process could solve the problem of post-treatments encountering the traditional leather processing. The enzymatic (rKERDZ) dehaired leather was analyzed by scanning electron microscopic (SEM) studies, which revealed similar fiber orientation and compactness compared with control sample. Those properties support that the rKERDZ enzyme–mediated process is greener to some extent than the traditional one.
显示更多 [+] 显示较少 [-]Water Qualities and Products Generated in Dechlorination Process Using Ultra-high Lime with Aluminum Method 全文
2021
Xu, Jiali | Chen, Peng | Dou, Chen | Yin, Di | Meng, GuangYuan | Cheng, Rui | Liu, Haifeng | Zhang, Lehua
Feasibility of dechlorination using ultra-high lime with aluminum process (UHLA) has been demonstrated by previous studies. However, the negative influences of UHLA on water qualities (pH, conductivity, and residual calcium concentration) after dechlorination and the products generated in dechlorination process have not been thoroughly analyzed. In this study, changes of water qualities at various dechlorination conditions were investigated, and favorable conditions for Friedel’s salt formation were explored by X-ray diffraction analysis. The pH and conductivity after dechlorination increased with the improvement of chloride removal effect. The calcium ion concentration in effluent also fluctuated with different dosages of CaO. At the maximum chloride removal efficiency of 71.4%, the pH, conductivity, and calcium ion concentration in effluent were 12.8, 10.9 ms/cm, and 22.7 mg/L, respectively. X-ray diffraction analysis for precipitants indicated that Friedel’s salt with the highest purity was also generated at the optimal dechlorination efficiency. The high dechlorination efficiency of 80.5% was achieved with the development of a stepwise addition strategy. Chemical costs for treating one ton of wastewater containing 500 mg/L chloride were $3.96.
显示更多 [+] 显示较少 [-]Adverse effects of short-term personal exposure to fine particulate matter on the lung function of patients with chronic obstructive pulmonary disease and asthma: a longitudinal panel study in Beijing, China 全文
2021
Duan, Ruirui | Niu, Hongtao | Yu, Tao | Huang, Ke | Cui, Han | Chen, Chen | Yang, Ting | Wang, Chen
Fine particulate matter (PM₂.₅) is an important environmental factor affecting human health. However, most studies on PM₂.₅ and health have used data from fixed monitoring sites to assess PM₂.₅ exposure, which may have introduced misleading information on the exposure–response relationship. We aimed to assess the effect of short-term personal PM₂.₅ exposure on lung function in patients with chronic obstructive pulmonary disease (COPD) and asthma. To achieve this, we conducted a longitudinal panel study among 37 COPD patients and 45 asthma patients from Beijing, China. The COPD group and the asthma group completed 148 and 180 lung function tests, respectively. We found that in COPD patients, for every 10-μg/m³ increase in PM₂.₅ exposure at lag2, the FEV₁, FVC and DLco decreased by −0.014 L (95% CI −0.025, −0.003), −0.025 L (95% CI −0.050, −0.003) and −0.089 mmol/min/kPa (95% CI −0.156, −0.023), respectively. There was also a decrease of −0.023 L/s (95% CI −0.042, −0.003) and −0.017 L/s (95% CI −0.032, −0.002) in MMEF at lag3 and lag03, respectively. In the asthma group, every 10-μg/m³ increase in PM₂.₅ exposure led to a reduction of −0.012 L (95% CI −0.023, −0.001), −0.042 L (95% CI −0.081, −0.003) and −0.061 L/s (95% CI −0.116, −0.004) in the FEV₁, FVC and PEF at lag3, respectively. Our findings suggest that PM₂.₅ exposure may primarily affect both airway function and lung diffusion function in COPD patients, and airway function in asthma patients.
显示更多 [+] 显示较少 [-]Management of human resources in the green economy: Does green labour productivity matter in low-carbon development in China 全文
2021
Soomro, Mansoor Mumtaz | Wang, Yanqing | Tunio, Raza Ali | Aripkhanova, Khamida | Ansari, Mohammad Ibrahim
Environmentally friendly economic development has become a global concern, whereas the existing literature has ignored the human resources management in the green economy. This study utilizes the basic Cobb–Douglas production function and examines the nonlinear effect of labour productivity on the environment in China. Non-linear findings infer that a positive change in labour productivity has a positive and negative change in labour productivity, and has a negative effect on CO₂ emissions in the short run, while results persisted and stable in the long run in China. The crux of this study is that labour productivity is vital for understanding the evolution of a green economy. Conventionally, capital productivity and energy consumption also tend to follow dirty productivity growth and thus, increased environmental pollution. Indeed, research and development is a forceful input to environmental quality. Based on findings, policymakers should need to focus on human resource productivity, green business, and ecosystem protection.
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