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81.

Economic complexity, biomass energy consumption, and information communication technology (ICT) have diverse impacts on energy consumption and carbon dioxide (CO2) emissions. Nevertheless, analysis of these variable effects is not addressed in the previous literature; the antiqueness of this article is stuffing this gap. This study assessed the relationship between gross domestic product (GDP) per capita, biomass consumption, economic complexity index (ECI), ICT, and CO2 emissions in Iran in 1994–2018. The autoregressive distributed lag (ARDL) model and the quantile regression (QR) econometric technique were used to investigate the factors affecting CO2 emissions in the tails of the conditional distribution. The share of each influential factor was predicted through the variance decomposition analysis (VD) for the next 10 years. The empirical results showed a long-run relationship between the variables. So, the variables of biomass consumption, ECI, and ICT improve the quality of the environment in Iran by reducing CO2 emissions, and the per capita GDP variable increases CO2 emissions. Results suggest no evidence indicating the presence of environmental Kuznets curve (EKC); however, QR demonstrated the existence of EKCs in the lower quantiles of the conditional distribution. The ECI will have the most share to change the CO2 emissions in the future. The income threshold should be determined at the turning point of the EKC to increase economic development. Moreover, investing in increasing biomass consumption is vital. Policymakers also need to consider strict added value for the export of products.

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82.
再生资源行业职业技能培训鉴定适应循环经济的要求,对提高从业人员素质、规范行业管理,促进再生资源产业发展具有重要作用。应充分利用行业协会平台,不断推进培训鉴定工作,全面提高再生资源行业的员工素质。  相似文献   
83.
Environmental Science and Pollution Research - UV filters as an important class of emerging organic pollutants are continuously released into and transported between the aquatic environments. So,...  相似文献   
84.
This research was carried out to evaluate the influence of static magnetic field on the rate of apoptosis in bone marrow stem cells (BMSCs) of rats. Extracted cells were suspended in αMEM as a culture media for 48 h. After that, cells were exposed to 15 mT static magnetic field (SMF) for 5 h, incessantly with or without FeCl2. The rate of apoptosis was then assessed via flow cytometery. The results showed that either treatment with FeCl2 or exposure to SMF enhanced the rate of apoptotic cells. Moreover, cells that were treated simultaneously with FeCl2 and SMF have higher rate of apoptosis. An increase in apoptosis by 26.5% was induced by SMF alone and an increase in apoptosis by 28.2% was induced by a combination of FeCl2 and SMF, compared to their corresponding controls. The results recommended that the effects of SMF on apoptosis may be related to increment of the number of free radicals in the cells.  相似文献   
85.
This article reports on the content and process used to evaluate environmental impacts caused by the development of 50 new settlements in the central Galilee region in northern Israel between 1978 and 1988. Some 60 different environmental and developmental factors and their interrelationships were identified. Selected physical changes that were defined as impacts were later evaluated. The evaluation method was based on intensive use of interviews with resource scientists and decision makers as experts. The data from interviews were used as the basis for factors identification, impact screening, and their rating. Experts used three types of criteria in the latter process: intensity of impact, the potential for its mitigation and compatibility with existing natural resource conservation, and environmental quality protection policy. Researchers concluded that reliance on experts with broad local experience eliminated the need for a more structured and detailed assessment method. The case study shows that experts provided creditable and reliable findings. They substituted the need for long periods of observation and largescale and costly data gathering, analysis, and evaluation.  相似文献   
86.
In this study, carbamazepine (CBZ) decay in solution has been studied by coupling electrocoagulation with electro-Fenton (EC-EF) with a novel P-rGO/carbon felt (CF) cathode, aiming to accelerate the in-situ generation of •OH, instead of adding Fe2+ and H2O2. Firstly, the fabricated P-rGO and its derived cathode were characterized by XRD, SEM, AFM, XPS and electrochemical test (EIS, CV and LSV). Secondly, it was confirmed that the performance in removal efficiency and electric energy consumption (EEC) by EC-EF (kobs=0.124 min−1, EEC=43.98 kWh/kg CBZ) was better than EF (kobs=0.069 min−1, EEC=61.04 kWh/kg CBZ). Then, P-rGO/CF (kobs=0.248 min−1, EEC=29.47 kWh/kg CBZ, CE=61.04%) showed the best performance in EC-EF, among all studied heteroatom-doped graphene/CF. This superior performance may be associated with its largest layer spacing and richest C=C, which can promote the electron transfer rate and conductivity of the cathode. Thus, more H2O2 and •OH could be produced to degrade CBZ, and almost 100% CBZ was removed with kobs being 0.337 min−1 and the EEC was only 24.18 kWh/kg CBZ, under the optimal conditions (P-rGO loading was 6.0 mg/cm2, the current density was 10.0 mA/cm2, the gap between electrode was 2.0 cm). Additionally, no matter the influent is acidic, neutral or alkaline, no additional pH adjustment is required for the effluent of EC-EF. At last, an inconsecutive empirical kinetic model was firstly established to predict the effect of operating parameters on CBZ removal.  相似文献   
87.

Production of Scenedesmus sp. biomass in chicken slaughterhouse wastewater (CSWW) is a promising alternative technique for commercial culture medium due to the high nutritional content of the generated biomass to be used as fish feeds. The current work deals with optimising of biomass production in CSWW using response surface methodology (RSM) as a function of two independent variables, namely temperature (10–30 °C) and photoperiod (6–24 h). The potential application of biomass yield as fish feeds was evaluated based on carbohydrate, protein and lipid contents. The results revealed that the best operating parameters for Scenedesmus sp. biomass production with high contents of carbohydrates, proteins and lipids were determined at 30 °C and after 24 h. The actual and predicted values were 2.47 vs. 3.09 g, 1.44 vs. 1.27 μg/mL, 29.9 vs. 31.60% and 25.75 vs. 28.44%, respectively. Moreover, the produced biomass has a high concentration of fatty acid methyl ester (FAME) as follows: 35.91% of C15:1; 17.58% of C24:1 and 14.11% of C18:1N9T. The biomass yields have 7.98% of eicosapentaenoic acid (EPA, C20:5N3) which is more appropriate as fish feeds. The Fourier transform infrared (FTIR) analysis of biomass revealed that the main functional groups included hydroxyl (OH), aldehyde (=C–H), alkanes and acyl chain groups. Scanning electron micrograph (SEM) and energy-dispersive X-ray spectroscopic analysis (EDS) indicated that the surface morphology and element distribution in biomass produced in BBM and CSWW were varied. The findings have indicated that the biomass produced in CSWW has high potential as fish feeds.

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88.
Hydrogeochemical data of groundwater from the semi-confined aquifer of a coastal two-tier aquifer in Amol–Ghaemshahr plain, Mazandaran Province, Northern Iran reveal salinization of the fresh groundwater (FGW). The saline groundwater zone is oriented at an angle to both Caspian Sea coastline and groundwater flow direction and extends inland from the coastline for more than 40 km. Spearman’s rank correlation coefficient matrices, factor analysis data, and values of C ratio, chloro-alkaline indices, and Na+/Cl? molar ratio indicate that the ionic load in the FGW is derived essentially from carbonic acid-aided weathering of carbonates and aluminosilicate minerals, relict connate saline water, and ion exchange reactions. Saline groundwater samples (SGWS) (n?=?20) can be classified into two groups. SGWS of group 1 (n?=?17) represent the saline groundwater zone below the Caspian Sea level, and salinization is attributed essentially to (1) lateral intrusion of Caspian seawater as a consequence of (a) excessive withdrawal of groundwater from closely spaced bore wells located in the eastern part of the coastal zone and (b) imbalance between recharge and discharge of the two-tier aquifer and (2) upconing of paleobrine (interfaced with FGW) along deep wells. SGWS of this group contain, on average, 7.9 % of saltwater, the composition of which is similar to that of Caspian seawater. SGWS of group 2 (n?=?3) belong to the saline groundwater zone encountered above the Caspian Sea level, and salinization of the groundwater representing these samples is attributed to irrigation return flow (n?=?2) and inflow of saline river water (n?=?1).  相似文献   
89.
90.
Slightly acidic solutions are a practical means of removing ammonia from air Scrubbed NH3 accumulates in solution as NH4+ and should be an excellent fertilizer Increased air velocity decreased NH3 removal and increased NH4+ collection Previous research on wet scrubbers has only studied highly acidic scrubbing solutions because of their high ammonia capture efficiencies; however, the high acidity created practical problems. Lower acidity solutions would reduce corrosion, maintenance, and cost; however, designers may need to use strategies for increasing scrubber effectiveness, such as using lower air velocities. The objective of this study was to determine if a spray scrubber with slightly acidic and higher pH scrubbing solution (pH from 2 to 8) could effectively remove NH3 from NH3 laden air (such as animal building exhaust air), and also collect this valuable resource for later use as a fertilizer. A bench-scale spray wet scrubber treated 20 ppmv NH3/air mixture in a countercurrent contact chamber. First, the solution pH was varied from 2 to 8 while maintaining constant air velocity at 1.3 m·s1. Next, air velocity was increased (2 and 3 m·s1) while solution pH remained constant at pH6. At 1.3 m·s−1, NH3 removal efficiencies ranged between 49.0% (pH8) and 84.3% (pH2). This study has shown that slightly acidic scrubbing solutions are a practical means of removing ammonia from air especially if the scrubber is designed to increase collisions between solution droplets and NH3 molecules. The NH3 removed from the air was held in solution as NH4+ and accumulates over time so the solution should be an excellent fertilizer.  相似文献   
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