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Fixation Effect of Fe3O4-GO to Hinder Pb(II) Translocation into Leek 全文
2020
Wang, Jing | Sun, Menglu | Chu, Chenlu | Yuan, Jian | Xing, Changrui
Agricultural soil is easily polluted by heavy metal and recently by metal-based nanoparticles, which has been synthesized in lab and discarded to environment. The uptake and accumulation of them by crops in polluted soil may pose high risks for human health. Here, we investigated the fate and the fixation effect of Fe₃O₄-GO nanocomposites (NCs) to lead ions in the soil-leek system during four harvest lifecycle. The results showed within 100 days, 600-mg/kg Fe₃O₄-GO significantly decreased Pb(II) concentrations in leaves by 37.89%, 39.10%, 73.86%, and 47.17% compared with controls. When Fe₃O₄-GO was added into Pb(II)-polluted soil, a significant fixation effect of Pb(II) was found, and the reduce percentages were 47.29%, 66.60%, 78.04%, and 39.16% for leaves, stem, storage roots, and absorbing roots compared with controls. The scanning electron microscope images showed that the overall appearance of Fe₃O₄-GO has not been destroyed during the interaction with soil. Graphical Abstract
显示更多 [+] 显示较少 [-]A Greenhouse Study of Concrete Grinding Residue Influences on Seedling Emergence and Early Growth of Selected Prairie Species 全文
2020
Luo, Chenyi | Wang, Zhuangji | Kordbacheh, Farnaz | Li, Shengting | Cetin, Bora | Ceylan, Halil | Horton, Robert
Concrete grinding residue (CGR) is a byproduct of diamond grinding, a road surface maintenance technique. Direct deposition of CGR along roadsides may influence plant growth, which has not been fully studied. Particularly, systematic experiments of CGR effects on selected common prairie species growth under controlled environments are rarely reported. Thus, in this study, a greenhouse experiment was performed to determine CGR effects on seedling emergence and aboveground biomass for four roadside prairie species: Indian grass, Canada wild rye, partridge pea, and wild bergamot. Nicollet loam and Hanlon fine sandy loam were used, and CGR of 4 rates, 0, 2.24, 4.48, and 8.96 kg m⁻², were applied in two ways, either mixed with the soil or applied on the soil surface. Multiple comparisons indicate that CGR produced mixed impacts on seedling emergence, depending on plant species, while aboveground biomass is not significantly influenced by CGR in general. ANOVA analysis with stepwise linear regression indicates that CGR had no uniform effects on seedling emergence, and CGR impacts should be studied for specific plant species and soil types. In conclusion, while CGR may lead to negative environmental issues on roadside plants depending on the plant species and soil types, if aboveground biomass is a major consideration, CGR effects are negligible. This study provides reference information for regulating CGR depositions along roadsides. Future studies may focus on investigating the relationship between CGR effects on seedling emergence and species succession in actual roadside environments.
显示更多 [+] 显示较少 [-]Assessment of preservative potential of Bunium persicum (Boiss) essential oil against fungal and aflatoxin contamination of stored masticatories and improvement in efficacy through encapsulation into chitosan nanomatrix 全文
2020
Singh, Akanksha | Deepika, | Chaudhari, Anand Kumar | Das, Somenath | Singh, Vipin Kumar | Dwivedy, Abhishek Kumar | Shivalingam, Ramani Kandasamy | Dubey, N. K.
The study reports the preservative efficacy of Bunium persicum (Boiss) essential oil (BPEO) against fungal and aflatoxin B₁ (AFB₁) contamination of stored masticatories and boosting of its efficacy through encapsulation into chitosan. BPEO was chemically characterized through GC-MS analysis, which revealed γ-terpinene as the major compound. The BPEO at 1.2 μL/mL concentration completely inhibited the growth of toxigenic strain of Aspergillus flavus (AF-LHP-PE-4) along with 15 common food borne moulds and AFB₁ secretion. The BPEO exerts its antifungal action on plasma membrane, as confirmed through ergosterol inhibition, alteration of membrane fluidity and enhancement of cellular ions and 260 and 280 nm absorbing material leakage. The antiaflatoxigenic mechanism of action of BPEO was confirmed through methylglyoxal reduction. Further, BPEO showed strong antioxidant activity (IC₅₀ = 7.36 μL/mL) as measured by DPPH· assay. During in situ investigation, BPEO completely inhibited AFB₁ production in model food (Phyllanthus emblica) system without altering the sensory properties and also exhibited high LD₅₀ value (14,584.54 μL/kg) on mice. In addition, BPEO was encapsulated into chitosan, characterized and tested for their potential to inhibit growth and AFB₁ production. The mean particle size, PDI and zeta potential of formed BPEO-loaded chitosan nanoparticle (CS-Np-BPEO) were performed to confirm successful encapsulation. The result revealed nanoencapsulated BPEO showed enhanced activity and completely inhibited the growth and AFB₁ production by AF-LHP-PE-4 at 0.8 μL/mL. Based on findings, it could be concluded that the BPEO and its encapsulated formulation can be recommended as a potential plant-based preservative against fungal and aflatoxin contamination of stored masticatories.
显示更多 [+] 显示较少 [-]Optimization of hyperconnected mobile modular production toward environmental and economic sustainability 全文
2020
Fergani, Charifa | El Bouzekri El Idrissi, Adiba | Marcotte, Suzanne | Hajjaji, Abdelowahed
Logistics sustainability is increasingly becoming a central focus of businesses, when most societies are aware of the influence of industry on both the environment and human health. To address the drawbacks of the way logistics systems have been designed, a new logistics system called Physical Internet has been proposed. This system relies on the creation of hyperconnected logistics systems. It aims to improve in an order of magnitude the way physical objects are transported, handled, stored, supplied, realized, and used to be more sustainable and efficient economically, environmentally, and socially. This paper focuses on the product realization using a hyperconnected mobile production mode in the context of Physical Internet, an open global logistics system. It addresses its dynamic deployment of production modules and resource allocation and sharing. It then proposes a make-to-order bi-objective optimization model which minimizes costs and greenhouse gases (GHGs) related to the product realization of a manufacturer to serve its customers given the availability of the open fabs. Experimental results are presented to identify the computational performance of the established model, as well as the economic and environmental benefits of using the facilities enabled by the PI. Finally, it concludes and provides directions for future research.
显示更多 [+] 显示较少 [-]The relationship between corporate social responsibility, environmental investments and financial performance: evidence from manufacturing companies 全文
2020
Shabbir, Malik Shahzad | Wisdom, Okere
The primary objective of this research is to ascertain the relationship between corporate social responsibility, environmental investments and financial performance in Nigerian manufacturing firms. The hypotheses are tested on internal environmental investments and external environmental investments on firm’s financial performance. It further determines if there is a significant difference between the profitability of environmentally conscious and environmentally non-conscious firms in Nigeria. Descriptive analysis is used to explain the variables applied and panel regression analysis is used to find out if there exists a relationship between internal environmental investments (employee benefits, staff training cost), external environmental investments (donations) and firm’s financial performance. The results indicate a positive and significant relationship exists between internal environmental investments and firm’s financial performance. It is also found a positive but insignificant relationship between external environmental investments and firm’s financial performance. Furthermore, paired sample t tests are used to reveal that there was a significant difference between the profitability of environmentally conscious and environmentally non-conscious firms. The finding of this study explains that firms with higher environmental investments have a higher profitability level than environmentally non-conscious firms.
显示更多 [+] 显示较少 [-]Synergistic effect of modified Pd-based cobalt chromite and manganese oxide system towards NO-CO redox detoxification reaction 全文
2020
Kerkar, Rahul D. | Salker, Arun V.
Surface architecting of the catalyst is a hopeful method to expand the surface property of the impetus material for upgrading their response towards the chemical reaction. In the present study, designing of the catalyst was carried out using specific transition metals to boost the simultaneous NO-CO conversion reaction catalytically. These metal oxide systems have been prepared using the combustion and wet impregnation method. Prepared oxides were characterized using XRD, BET, XPS, SEM, and TEM. Further, the surface phenomenon of the catalyst was monitored through H₂-TPR, O₂-TPO, NO-TPD, and CO-TPD studies. The highly remarkable activity was perceived by Pd-based modified manganese oxide-cobalt chromite system as compared with simple Pd-based manganese oxide and Pd-based cobalt chromite. The catalyst showed the highest activity for NO-CO redox reaction with T₁₀₀ at 170 °C. Also, good stability was observed with a runtime of 7 h.
显示更多 [+] 显示较少 [-]Spatial and temporal variation of zooplankton assemblage in the mining-impacted stretch of Ganga River, Uttarakhand, India 全文
2020
Kamboj, Vishal | Kamboj, Nitin
The spatial and temporal variation in the distribution, abundance and assemblage structure of zooplankton were examined in a mining-impacted stretch of river Ganga. The collection of samples has been done from three different sampling zones such as Z1 (Chandi Bridge Ghat) as reference zone, Z2 (Shyampur), and Z3 (Bisanpur) as mining-intruded area from May 2017 to April 2018. During the analysis, twenty-eight species of zooplankton kindred to four groups mainly Rotifera (ten species), Protozoa (five species), Cladocera (eight species), and Copepoda (five species) were identified. In the course of analysis, it was observed that Rotifera were dominant (43.49 %) followed by Cladocera (19.58 %), Protozoa (18.31 %), and Copepoda (18.62 %). The results showed that the distribution and abundance of zooplankton fluctuated more at Z1 (reference zone) as compared with Z2 and Z3 (mining-intruded zones). The diversity indices also indicated the higher richness, abundance, and evenness of zooplankton ranging from 3.145 to 3.180 at Z1, 3.081 to 3.129 at Z2, and 3.130 to 3.175 at Z3. The canonical correspondence analysis (CCA) showed positive and negative correlation between the zooplankton and water quality of the river Ganga. The present study shows that the anthropogenic activities such as river bed mining disturbed the water quality through enhancing the turbidity and nutrients load in the aquatic system. However, these changes in water quality significantly affected the distribution and abundance of zooplankton.
显示更多 [+] 显示较少 [-]Effect of organic matter derived from algae and macrophyte on anaerobic ammonium oxidation coupled to ferric iron reduction in the sediment of a shallow freshwater lake 全文
2020
Yao, Zongbao | Yang, Liu | Song, Na | Wang, Changhui | Jiang, Helong
As a recently discovered process of nitrogen cycling, anaerobic ammonium oxidation coupled to ferric iron reduction (Feammox) has attracted more attentions. This study investigated the spatial variation of Feammox in the sediment of different zones of a shallow freshwater lake and the effect of organic matter derived from algae and macrophyte on Feammox process. The potential Feammox rates showed significant differences among sediments from algae-dominated area (ADA), transitional area in the center of the lake (TDA), and macrophyte-dominated area (MDA), and in a descending order, ADA, MDA, and TDA. The potential Feammox rate ranged from 0.14 to 0.34 mg N kg⁻¹day⁻¹ in the freshwater lake sediment. The potential Feammox rates of the sediment with algae or macrophyte amendment were 12.29% and 15.31% higher than the control test without algae and macrophyte amendment. The addition of algae or macrophyte to the sediment from TDA could improve the amount of HCl-extractable total Fe, Fe(III) reduction rate, and the abundance of FeRB. These results demonstrated that organic matter is one of the key regulators of Feammox process.
显示更多 [+] 显示较少 [-]Coagulation- and Adsorption-Based Environmental Impact Assessment and Textile Effluent Treatment 全文
2020
Aleem, Muhammad | Cao, Jiashun | Li, Chao | Rashid, Haroon | Wu, Yang | Nawaz, Muhammad Imran | ʻAbbās, Muḥammad | Akram, Muhammad Waqar
Disposal of industrial effluents (especially the textile industry) into the drains without prior treatment is a common practice that affects aquatic life and pollutes the soil and groundwater quality. Textile effluents contain organic and inorganic pollutants in terms of high pH, suspended and dissolved solids, chemical oxygen demand, heavy metals, and many other contaminants. Therefore, it is obligatory to dispose off wastewater according to environmental standards. The present study is planned to determine textile wastewater characteristics and recommend efficient and economical treatment options. Wastewater samples from three different industries were collected and analyzed. Nine different treatments using different dosages of alum, activated carbon, and their mixture were used to investigate treatment performance. Analysis of variance and correlation was used to optimize the results. A highly significant correlation was found among the treatments ranging from 92 to 100% for observed parameters. pH, chemical oxygen demand, and total suspended solids were removed significantly. A combination of alum and activated carbon found to be the most efficient treatment. Based on the highly significant results among different parameters, a combined wastewater treatment plant is recommended for a cluster of industrial units.
显示更多 [+] 显示较少 [-]Mathematical Modelling for Predicting Pollutant Removal Efficiencies of an Electrolysis System 全文
2020
Imteaz, Monzur A. | Ahsan, Amimul | Kaur, Parminder | Shanableh, Abdallah
Electrolysis systems have been widely investigated for treating wastewater in laboratory-scale experiments, and most researchers reported efficient treatment outcomes. However, industrial scale implementation often necessitates assessing and prioritising various options involving different combinations of input parameters, which often requires mathematical models. This study presents mathematical models for predicting removal efficiencies of four different pollutants using electrolysis. Parametric equations were developed based on experimental results conducted in a previous study. Proposed equations are dependent on treatment retention time and current intensity (voltage). Results revealed that the experimental data followed consistent patterns, which lead to the derivations of generalised equations which were able to closely predict pollutants’ removal efficiencies obtained through experimental measurement. The developed equations also confirmed that beyond an optimum voltage, a further increase in voltage does not render higher removals of the pollutants, which is essential for enhancing the feasibility of industrial scale applications.
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