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Green certificates as an instrument to support renewable energy in Poland—strengths and weaknesses 全文
2020
Adamczyk, Janusz | Graczyk, Magdalena
The problem of air pollution not only in Poland but also around the world has become an important topic of political, economic, scientific, and legal discourse. Its position is the result of international obligations and Poland’s membership in the structures of the European Union. In Poland, air quality is very bad, which makes it one of the countries with the worst air quality indicators in the European Union. One of the methods to reduce this high level of air pollution is to intensify the development of renewable energy sources by introducing effective support mechanisms for investors of new user-friendly and environment-friendly energy. The aim of the article was to analyse the support system for the development of energy production from renewable sources using the so-called “green” certificates of origin mechanism, which in Poland already has a 14-year tradition. The article presents the model of the renewable energy production support system in force in Poland. It pointed to its strengths and weaknesses. The development trends of the RES support system were also presented.
显示更多 [+] 显示较少 [-]Effect of LCRS clogging on leachate recirculation and landfill slope stability 全文
2020
Feng, Shi-Jin | Chen, Zheng-Wei | Zheng, Qi-Teng
Vertical wells are commonly used for recirculating leachate into a landfill which can offer significant environmental and economic benefits. However, in some cases, the leachate collection and removal system (LCRS) at the bottom is overloaded and clogged due to biological and chemical processes. This results in a relatively high leachate level which could pose a threat to landfill slope stability. This study develops a three-dimensional landfill slope model with vertical recirculation wells and then investigates the effect of LCRS clogging on leachate recirculation and slope stability in terms of leachate saturation, pore water pressure, and factor of safety (FS) of a landfill slope. The results show that with an increase in clogging level that is characterized by an increased leachate level, the pore water pressure below the well injection screen is significantly increased by leachate recirculation, giving rise to a decreased slope FS value. In such conditions, the landfill slope formed by highly anisotropic waste is more likely to suffer instability. To prevent this kind of slope failure, a safe injection pressure of vertical recirculation wells is proposed for a wide range of parameter combinations involving waste anisotropy, clogging level, and the setback distance from the slope surface. This design guideline can be used to control the injection pressure in leachate recirculation applications and contributes to a better understanding of the slope stability of a bioreactor landfill.
显示更多 [+] 显示较少 [-]Catalytic activity of acid-treated biomass for the degradation of expanded polystyrene waste 全文
2020
Rex, Prathiba | Miranda, Lima Rose
Pyrolysis processes were investigated using expanded polystyrene waste (EPW) with a catalyst synthesized from rice husk (RH). Biomass was treated with different acids, i.e., sulfuric acid, oxalic acid, and hydrochloric acid. The effect of normality on the oxalic acid-treated catalyst and the effects of polymer to catalyst ratio on (i) oil, gas, and residues yields; (ii) temperature; and (iii) time for the complete reaction were investigated for the effective use of oil for fuel production. The catalyst treated with 0.25 N (RHOA₀.₂₅) resulted in a high oil yield of 96 wt% and a residue yield of 3.47 wt%. The oil produced contained mainly aromatic compounds, which contributed 67.86% in an area-based GC-MS analysis. The synthesized catalyst showed a stable capacity for three regeneration runs. The significant factor is that the synthesized catalyst decreased the activation energy during the pyrolysis of EPW. Graphical abstract
显示更多 [+] 显示较少 [-]Identification and expression analysis of conserved microRNAs during short and prolonged chromium stress in rice (Oryza sativa) 全文
2020
Dubey, Sonali | Saxena, Sharad | Chauhan, Abhishek Singh | Mathur, Priyanka | Rani, Vibha | Chakrabaroty, Debasis
MicroRNAs (miRNAs) are one of the most critical epigenetic regulators of gene expression which modulate a spectrum of development and defence response processes in plants. Chromium (Cr) contamination in rice imposes a serious concern to human health as rice is used as staple food throughout the world. Although several studies have established the differential response of miRNAs in rice during heavy metal (arsenic, cadmium) and heat or cold stress, no report is available about the response of miRNAs during Cr stress. In the present study, we identified 512 and 568 known miRNAs from Cr treated and untreated samples, respectively. Expression analysis revealed that 13 conserved miRNAs (miR156, miR159, miR160, miR166, miR169, miR171, miR396, miR397, miR408, miR444, miR1883, miR2877, miR5072) depicted preferential up- or down-regulation (> 4-fold change; P value < 0.05). Target gene prediction of differentially expressed miRNAs and their functional annotation suggested the important role of miRNAs in defence and detoxification of Cr though ATP-binding cassette transporters (ABC transporters), transcription factors, heat shock proteins, auxin response, and metal ion transport. Real-time PCR analysis validated the differential expression of selected miRNAs and their putative target genes. In conclusion, our study identifies and predicts miRNA-mediated regulation of signalling pathway in rice during Cr stress.
显示更多 [+] 显示较少 [-]Curcumin phytosome modulates aluminum-induced hepatotoxicity via regulation of antioxidant, Bcl-2, and caspase-3 in rats 全文
2020
Al-Kahtani, Mohammed | Abdel-Daim, Mohamed M. | Sayed, Amany A. | El-Kott, Attalla | Morsy, Kareem
Increasing entrance of aluminum chloride (AlCl₃) in many fields exposes human beings to its biotoxicity. Thereby, the present study assesses the potential ameliorative role of curcumin phytosome (CP) on AlCl₃-induced hepatotoxicity. Rats were divided into four groups (n = 6): group 1 served as control; group 2 received CP (200 mg CP/kg b.wt) for 21 days; group 3 injected three doses of AlCl₃ (30 mg/kg/body weight) every 5 days intraperitoneally; group 4 received CP for 7 days prior to AlCl₃ and then received CP concurrently with AlCl₃ for another 14 days. AlCl₃ markedly increased (P < 0.05) the concentrations of AST, ALT, ALP, LDH, total bilirubin, and LPO as well as depleted (P < 0.05) albumin, GSH, SOD, and GPx stores in comparison to the control group. These biochemical alterations supported by the lesion observed in histological sections, increasing the expression of caspase-3 and decreasing the expression of Bcl-2. Treatment with CP modulates the hepatic dysfunction, boosting the endogenous antioxidant status, downregulating the expression of caspase-3, and upregulating the expression of Bcl-2. This hepatic ameliorative effect may be mediated by the ability of CP to repair the oxidant/antioxidant equilibrium rather than its ability to suppress apoptosis.
显示更多 [+] 显示较少 [-]Simultaneous roxarsone photocatalytic degradation and arsenic adsorption removal by TiO2/FeOOH hybrid 全文
2020
Fu, Wentao | Lu, Dong-Lei | Yao, Hang | Yuan, Shoujun | Wang, Wei | Gong, Miao | Hu, Zhen-Hu
Roxarsone (3-nitro-4-hydroxyphenylarsonic acid) is an extensively used organoarsenic feed additive. The effective removal of arsenic from roxarsone degradation before discharging is of great importance for controlling artificial arsenic pollution in aquatic environment. In this study, a bifunctional TiO₂/ferrihydrite (TiO₂/FeOOH) hybrid was synthesized by a hydrothermal method for the simultaneously photocatalytic degradation of roxarsone and adsorption removal of released arsenic. The analysis of the prepared TiO₂/FeOOH by field-emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), Raman spectra, X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS) confirmed the successful formation of the hybrid of crystalline TiO₂ and no crystalline FeOOH. TiO₂/FeOOH hybrid had better adsorption capacity for As(V) than roxarsone. Compared to TiO₂, the TiO₂/FeOOH hybrid exhibited much superior UV-driven photocatalytic activities for roxarsone degradation. After 12 h irradiation, more than 96% of roxarsone was degraded by 1:1 TiO₂/FeOOH hybrid, and the released As(V) was simultaneously removed from the solution. The residual As(V) concentration was lower than 0.02 mg L⁻¹. The reusability test indicated that TiO₂/FeOOH hybrid had excellent stability and reliability. The possible mechanism of roxarsone degradation and released inorganic arsenics removal by this hybrid was also proposed. These results clearly indicated that the TiO₂/FeOOH hybrid could be used for the removal of roxarsone and its degradation product.
显示更多 [+] 显示较少 [-]Urbanization increases carbon concentration and pCO2 in subtropical streams 全文
2020
das Neves Lopes, Michelle | Decarli, Cleiton Juarez | Pinheiro-Silva, Lorena | Lima, Thiago Cesar | Leite, Nei Kavaguichi | Petrucio, Mauricio Mello
Urbanization growth may alter the hydrologic conditions and processes driving carbon concentrations in aquatic systems through local changes in land use. Here, we explore dissolved carbon concentrations (DIC and DOC) along urbanization gradient in Santa Catarina Island to evaluate potential increase of CO₂ in streams. Additionally, we assessed chemical, physical, and biotic variables to evaluate direct and indirect effects of urbanization in watersheds. We defined 3 specific urbanization levels: high (> 15% urbanized area), medium (15–5% urbanized area), and low (< 5% urbanized area) urbanization. The results showed that local changes due to growth of urban areas into watersheds altered the carbon concentrations in streams. DOC and DIC showed high concentrations in higher urbanization levels. The watersheds with an urban building area above 5% showed pCO₂ predominantly above the equilibrium with the atmosphere. These findings reveal that local modifications in land use may contribute to changes in global climate by altering the regional carbon balance in streams.
显示更多 [+] 显示较少 [-]Localization of mercury and gold in cassava (Manihot esculenta Crantz) 全文
2020
Alcantara, Hannah Joy P. | Jativa, Fernando | Doronila, Augustine I. | Anderson, Christopher W. N. | Siegele, Rainer | Spassov, Tony G. | Sanchez-Palacios, Jose T. | Boughton, Berin A. | Kolev, Spas D.
The potential of cassava (Manihot esculenta Crantz.) for simultaneous Hg and Au phytoextraction was explored by investigating Hg and Au localization in cassava roots through Micro-Proton Induced X-Ray Emission, High-Resolution Transmission Electron Microscopy (HR-TEM) and X-Ray Diffractometry (XRD). The effect of Hg and Au in the cyanogenic glucoside linamarin distribution was also investigated using Matrix Assisted Laser Desorption Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (MALDI-FT-ICR-MS) imaging. Hg was located mainly in the root vascular bundle of plants grown in 50 or 100 μmol L⁻¹ Hg solutions. Au was localized in the epidermis and cortex or in the epidermis and endodermis for 50 and 100 μmol L⁻¹ Au solutions, respectively. For 50 μmol L⁻¹ solutions of both Hg and Au, the two metals were co-localized in the epidermis. When the Hg concentrations were increased to 100 μmol L⁻¹, Au was still localized to a considerable extent in the epidermis while Hg was located in all root parts. HR-TEM and XRD revealed that Au nanoparticles were formed in cassava roots. MALDI-FT-ICR-MS imaging showed linamarin distribution in the roots of control and plants and metal-exposed plants thus suggesting that linamarin might be involved in Hg and Au uptake and distribution.
显示更多 [+] 显示较少 [-]Is technological innovation the effective way to achieve the “double dividend” of environmental protection and industrial upgrading? 全文
2020
Wang, Gege | Liu, Shulin
In recent years, the global emphasis on environmental protection issues has gradually increased. The existing literature has been divided on whether environmental regulation promotes or inhibits industrial development. Can the innovation-driven strategy proposed by China achieve a win-win situation for both? This paper attempts to investigate the technology innovation of China’s three major economic zones in dual environmental regulation effect on industrial structure upgrade. The research was conducted based on Intermediary Effect Model and employing the technique of Image Analysis, panel data of 30 Chinese provincial from in 2005 to 2017 were selected and analyzed. The results demonstrate that the direct effect of formal environmental regulations (ER) on industrial upgrading is an inverted “U” shape, and it is positively affecting industrial upgrading through technological innovation strategies. However, the mediating role of technological innovation under the informal environmental regulation (IER) is negative. The effect of the innovation-driven strategy has regional heterogeneity, and marketization is conducive to industrial upgrading, but increasing dependence on foreign trade is not conducive to industrial upgrading. The research above politically suggests that China should further strengthen formal and informal environmental regulations, the informal environmental regulation system should be improved, and feedback mechanisms such as laws should be established. Meanwhile, the government should carry out innovation-driven strategies based on local conditions, improve the innovation mechanism, and enhance the diffusion of technological innovation.
显示更多 [+] 显示较少 [-]State of a sustainable drainage system at end-of-life: assessment of potential water pollution by leached metals from recycled pervious pavement materials when used as secondary aggregate 全文
2020
Mbanaso, Fredrick U. | Charlesworth, Susanne M. | Coupe, Stephen J. | Newman, Alan P. | Nnadi, Ernest O.
Sustainable drainage systems (SuDS) have emerged as an effective and attractive approach for stormwater management, prevention of water pollution and flood control due to its sustainable, environmentally friendly and cost-effective approaches. One of the SuDS devices widely used to infiltrate, store and treat surface runoff which allows it to recharge groundwater is the pervious paving systems (PPS). Previous studies have demonstrated relatively high pollution removal efficiencies typically ranging from 98.7% for total hydrocarbons to 89% of COD. Although a small number of the studies have assessed the performance characteristics of the PPS system in long-established installations in terms of retention of pollutants, hydrological features, biodegradation of pollutants etc., none has assessed the risk of potential groundwater and soil pollution by pollutants such as metals retained in the PPS materials either as a disposed waste material (in the case of used geotextiles) or during re-use as secondary aggregates. Thus, this study evaluated potential risks associated with the decommissioning and beneficial use of wastes produced during the disassembly of a PPS. The authors believe that this was the first PPS to be addressed in this way. The method involved the determination of leachable concentrations of 14 metals in the PPS samples made up of extracts from the model profile which included the geotextile fibre (G), dust alone (D), aggregates and dust (AD), aggregates alone (AA) and pavement blocks (P) which were analysed and compared with two different groups of regulatory threshold limits. The results showed that the measured concentrations of all the metals were below the appropriate threshold values for irrigation purposes as specified by FAO and USEPA. Furthermore, results all indicated that the dismantled materials were all below EU LFD WAC limits for inert waste, indicating relative ease of disposal and suitability for use as recycled aggregate. This, admittedly limited data, indicates that recycling of aggregates from demolition wastes arising from end of life PPS would not be limited by the potential leaching of heavy metals, including re-use within another PPS. This would minimise dependence on virgin aggregates and hence reduce rate of exploitation of natural resources and improve sustainability score card of SuDS.
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