The use of nanovermiculite catalyst in the study of removal of the organic load and degradation of atrazine via ozone process in RPB reactor

Abstract

The main objective of this study is the degradation of a synthetic solution of atrazine by a modified vermiculite catalyzed ozonation, in a rotating packed bed (RPB) reactor. A 0.5?L RPB reactor was used to perform the experiments, using a Central Composite Design (CCD) response surface to construct the quadratic model based on the factors: pH, catalyst concentration and reactor rotation frequency. The response variable was the removal of the organic load measured in terms of Chemical Oxygen Demand (COD). After the complete quadratic model was constructed through the response surface, the COD degradation process had an optimal removal of 41% under the following conditions: pH 8.0, rotation of 1150?rpm and catalyst concentration 0.66?g L^?1.     

A fractal derivative model to quantify bed-load transport along a heterogeneous sand bed

Environmental Fluid Mechanics - Bed-load transport is a complex process exhibiting anomalous dynamics, which cannot be efficiently described using the traditional advection–diffusion...     

Influence of Chronic Man-made Pollution on Bromus inermis Genome Size

Russian Journal of Ecology - Technogenic pollution can accelerate microevolutionary processes in natural populations. We estimated the nuclear DNA content of 10 Bromus inermis Leyss. samples from...     

Application of environmentally conscious manufacturing strategies for an automotive component

Application of appropriate environmentally conscious manufacturing strategies enables the sustainable development of products and processes. Automotive component manufacturers recognise the potential of applying appropriate strategies for attaining Triple Bottom Line benefits. In this context, three strategies such as eco-efficiency, waste minimisation and material efficiency are being applied to minimise environmental impacts associated with the manufacture of automotive products and its associated processes. A case study of an automotive component manufacturing firm has been exemplified. After conducting the study, the potential environmental impact was reduced by 20% and eco-efficiency was improved by 13%. Further, improvements have been observed in terms of overall resource consumption and material efficiency. The overall power consumption was reduced by 18% and weight of the component was reduced by 11%. The study aimed at improving the sustainable performance of product by incorporating green and environmentally friendlier manufacturing practices.

Abbreviations: USEPA: United Nations Environmental Protection Agency; OECD: Organisation for Economic Co-operation and Development; WBCSD: World Business Council for Sustainable Development; Eco-QFD: Environmental Quality Function Deployment; WCED: World Commission on Environment and Development; LCA: Life Cycle Assessment     

Prioritizing sites for conservation based on similarity to historical baselines and feasibility of protection

The concept of shifting baselines in conservation science implies advocacy for the use of historical knowledge to inform these baselines but does not address the feasibility of restoring sites to those baselines. In many regions, conservation feasibility varies among sites due to differences in resource availability, statutory power, and land‐owner participation. We used zooarchaeological records to identify a historical baseline of the freshwater mussel community's composition before Euro‐American influence at a river‐reach scale (i.e., a kilometer stretch of river that is abiotically similar) in the Leon River of central Texas (U.S.A.). We evaluated how the community reference position and the feasibility of conservation might enable identification of sites where conservation actions would preserve historically representative communities and be likely to succeed. We devised a conceptual model that incorporated community information and landscape factors to link the best conservation areas to potential cost and conservation benefits. Using fuzzy ordination, we identified modern mussel beds that were most like the historical baseline. We then quantified housing density and land use near each river reach identified to estimate feasibility of habitat restoration. Using our conceptual framework, we identified reaches of high conservation value (i.e., contain the best mussel beds) and where restoration actions would be most likely to succeed. Reaches above Lake Belton were most similar in species composition and relative abundance to zooarchaeological sites. A subset of these mussel beds occurred in locations where conservation actions appeared most feasible. Our results show how to use zooarchaeological data (biodiversity data often readily available) and estimates of conservation feasibility to inform conservation priorities at a local spatial scale.     

Boosting large-scale river connectivity restoration by planning for the presence of unrecorded barriers

Conservation decisions are invariably made with incomplete data on species’ distributions, habitats, and threats, but frameworks for allocating conservation investments rarely account for missing data. We examined how explicit consideration of missing data can boost return on investment in ecosystem restoration, focusing on the challenge of restoring aquatic ecosystem connectivity by removing dams and road crossings from rivers. A novel way of integrating the presence of unmapped barriers into a barrier optimization model was developed and applied to the U.S. state of Maine to maximize expected habitat gain for migratory fish. Failing to account for unmapped barriers during prioritization led to nearly 50% lower habitat gain than was anticipated using a conventional barrier optimization approach. Explicitly acknowledging that data are incomplete during project selection, however, boosted expected habitat gains by 20–273% on average, depending on the true number of unmapped barriers. Importantly, these gains occurred without additional data. Simply acknowledging that some barriers were unmapped, regardless of their precise number and location, improved conservation outcomes. Given incomplete data on ecosystems worldwide, our results demonstrate the value of accounting for data shortcomings during project selection.     

Investigation of modified horizontal wing cut twisted tapes fitted with rod and spacer at trailing edge on heat transfer properties in Double Glazing V-Trough solar water heaters

An experimental analysis of heat transfer efficiency in double glazing solar water heating system having full-length Horizontal wing cut twisted tapes having twist ratio 3 fitted with rod or spacer of dimensions 125 mm, 250 mm, and 500 mm as length at the trailing edges has been dealt in this work. The experimental results have been compared with a plain tube with similar operating conditions and concluded that variation in the Nusselt number, as well as friction factor, are ±12.56% and ±10.17%, respectively. The result of empirical correlation concludes that Nusselt number is maximal for horizontal wing cut twisted tapes having rod or spacer at its ends while comparing with full-length horizontal wing cut twisted tapes. The friction factor is low for full-length horizontal wing cut twisted tapes than the horizontal wing cut twisted tapes fitted with rod or spacer. The horizontal wing cut twisted tapes fitted with rod has superior performance than twist fitted with spacer.     

Are the costs worth the benefits? Shared perception and the aggregation of organizational climate ratings

A definitional component of organizational climate is the focus on employees' shared perceptions of the focal climate domain. To operationalize the notion of sharedness, researchers typically aggregate employees' domain‐specific climate perceptions to a higher level and justify this aggregation using quantitative indices of agreement. In the current paper, I argue that although accounting for sharedness among employees can provide some valuable insight, our overreliance on sharedness obscures some of the very organizational phenomena of interest. I discuss this issue by focusing on four costs of making unfounded assumptions regarding sharedness: (a) Aggregation assumes individual differences are a function of random error; (b) aggregation assumes that social situations are uniform across employees; (c) aggregation assumes that the unit of analysis is clear‐cut; and (d) aggregation assumes the group mean is meaningful. I argue that researchers carefully need to weigh the costs of violating these assumptions against the expected benefits of aggregating employees' climate perceptions, recognizing that sometimes employees' perceptions (i.e., psychological climate) might provide greater insight into phenomena of interest. Although I discuss these costs within the context of organizational climate research, these arguments apply to other research areas where individual perceptions are aggregated (e.g., research on leadership and teams).     

Electrocatalytic oxidation of ciprofloxacin by Co-Ce-Zr/γ-Al2O3 three-dimensional particle electrode

Environmental Science and Pollution Research - In this work, Co-Ce-Zr/γ-Al2O33 particle electrodes were prepared for the efficient degradation of ciprofloxacin (CIP). Co-Ce-Zr/γ-Al2O3...     

Impact of the Jatoba shell residue amount on polyurethane foams based on castor polyol

Journal of Material Cycles and Waste Management - This study proposes an alternative for Jatoba shell residues as reinforcement in castor oil-based polyurethane (PU), obtaining an eco-friendly...