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91.
Environmental Science and Pollution Research - In the present paper, different types of pure and commercial plastic waste from different EU countries (UK, France, Italy, and Romania) were...  相似文献   
92.
Used batteries contain numerous metals in high concentrations and if not disposed of with proper care, they can negatively affect our environment. These metals represent 83% of all spent batteries and therefore it is important to recover metals such as Zn and Mn, and reuse them for the production of new batteries. The recovery of Zn and Mn from used batteries, in particular from Zn–C and alkaline ones has been researched using hydrometallurgical methods. After comminution and classification of elemental components, the electrode paste resulting from these processes was treated by chemical leaching. Prior to the leaching process the electrode paste has been subjected to two washing steps, in order to remove the potassium, which is an inconvenient element in this type of processes. To simultaneously extract Zn and Mn from this paste, the leaching method in alkaline medium (NaOH solution) and acid medium (sulphuric acid solution) was used. Also, to determine the efficiency of extraction of Zn and Mn from used batteries, the following variables were studied: reagents concentration, S/L ratio, temperature, time. The best results for extraction yield of Zn and Mn were obtained under acid leaching conditions (2 M H2SO4, 1 h, 80 °C).  相似文献   
93.
94.

The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater has been reported as a result of fecal shedding of infected individuals. In this study, the occurrence of SARS-CoV-2 RNA was explored in primary-treated wastewater from two municipal wastewater treatment plants in Quintana Roo, Mexico, along with groundwater from sinkholes, a household well, and submarine groundwater discharges. Physicochemical variables were obtained in situ, and coliphage densities were determined. Three virus concentration methods based on adsorption-elution and sequential filtration were used followed by RNA isolation. Quantification of SARS-CoV-2 was done by RT-qPCR using the CDC 2020 assay, 2019-nCoV_N1 and 2019-nCoV_N2. The Pepper mild mottle virus, one of the most abundant RNA viruses in wastewater was quantified by RT-qPCR and compared to SARS-CoV-2 concentrations. The use of three combined virus concentration methods together with two qPCR assays allowed the detection of SARS-CoV-2 RNA in 58% of the wastewater samples analyzed, whereas none of the groundwater samples were positive for SARS-CoV-2 RNA. Concentrations of SARS-CoV-2 in wastewater were from 1.8 × 103 to 7.5 × 103 genome copies per liter (GC l−1), using the N1 RT-qPCR assay, and from 2.4 × 102 to 5.9 × 103 GC l−1 using the N2 RT-qPCR assay. Based on PMMoV prevalence detected in all wastewater and groundwater samples tested, the three viral concentration methods used could be successfully applied for SARS-CoV-2 RNA detection in further studies. This study represents the first detection of SARS-CoV-2 RNA in wastewater in southeast Mexico and provides a baseline for developing a wastewater-based epidemiology approach in the area.

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95.
Abstract

In this paper we examine the relationship between identification with the environmental movement and support for First Nations' land claims in order to determine the potential for an environmental justice movement in British Columbia. The findings are based on survey data collected from members of a wilderness preservation movement organization based on Vancouver Island. The findings demonstrate that the stronger an individual identifies with the environmental movement, the more s/he supports linking First Nations' land claims to conservation campaigns. We conclude by proposing that the wilderness preservation movement could increase its mobilization potential and widen the scope of the movement by including First Nations' issues in their campaigns. It could do this by expanding its frame to include issues of environmental justice, thereby connecting environmental protection and fair access to resources.  相似文献   
96.
Environment, Development and Sustainability - Urbanization has threatened rural communities’ livelihoods worldwide, changing their agro-food systems from locally produced traditional items to...  相似文献   
97.
98.
Cd, Zn, Cu, and metallothionein (MT) levels have been determined in the renal cortex and liver of 70 persons who died in Lodz and its surroundings in the years 1985–1989. The mean concentrations were: 44.9±28.6 µg Cd/g, 52.0±16.7 µg Zn/g, 2.4±1.0 µg Cu/g, 0.79±0.40 µmol Hg/g, and 3.5±1.8 µg Cd/g, 66.7±30.5 µg Zn/g, 4.9±2.1 µg Cu/g, 0.50±0.38 µmol Hg/g wet tissue in renal cortex and liver, respectively, with mean age 54.0±13.8. Smokers showed 2.4 times higher levels of Cd in the renal cortex than non-smokers. The mean body burden of Cd was 33.4±17.3 mg. Smoking increases it twofold from 22.0 mg in non-smokers to 41.8 mg in smokers.This work was supported by the grant CPBR 11.12(C-56/86) from the Institute of Rural Medicine, Lublin, Poland.Deceased.  相似文献   
99.
The present study was designed to evaluate the effect of a natural prey (the crab Callinectes sp.) and an artificial diet (pellet with squid paste and offered as a paste) on the survival and assimilation efficiency of subadult octopuses with 486 g of initial live weight. In order to reach this goal, the effects of the type of diet on energetic balance were assessed by recording ingestion rate (C), respiratory rate (R = R routine, R rout + R apparent heat increment, R AHI), ammonia production rate (U = U routine, U rout + U post-prandial, U PP) and biomass production (P) of Octopus maya during its growing process. Energy lost from faeces (H) was calculated as H=C−(U+R+P) and assimilated energy (As) as R + P. Octopuses fed an artificial diet had almost five times higher ingestion rate compared to that observed in octopuses fed crab. However, growth rate and production (P) were high in octopuses fed crab in comparison to octopuses fed artificial diet. An inverse relation between faeces (H) and type of food was observed, indicating that animals lost 77% of the ingested energy when fed artificial diet and only 5% when fed crab. A higher assimilation and production efficiency were obtained in octopuses fed crab (P/As: 61%) than in animals fed the artificial diet (P/As: −5%). The routine O : N ratio for animals in fasting was 9.1 and 2.3 for octopuses being fed crabs and the artificial diet, respectively. The post-alimentary O : N ratio was 3.6 and 2.2 for animals fed crabs and the artificial diet, respectively. This indicates that animals fed on both diets rely almost exclusively on protein. Based on energy balance data, a value of 472 kJ week−1 kg−1 of live octopus was estimated as the energy needed to obtain a growth rate near 9 g day−1 (2.8% BW day−1) for O. maya subadults. The total crab biomass needed to obtain 1 kg of fed O. maya biomass was calculated. A comparison with other different energy balance measurements made in other octopus species indicates that O. maya and Enteroctopus megalocyathus (Pérez et al. 2006) tend to be more efficient by channelling more ingested energy to biomass production (P = 69.5% of C) than O. vulgaris (P = 23% of C; Petza et al. 2006) or Paraledone charcoti (P = 4% of C; Daly and Peck 2000).  相似文献   
100.
Environmental Chemistry Letters - Pollution by toxic metals is a worldwide health issue, yet analytical methods to monitor selectively metal ions in complex media are limited. Fluorescence sensing...  相似文献   
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