Au nanoring arrays as surface enhanced Raman spectroscopy substrate for chemical component study of individual atmospheric aerosol particle

Monolayer-ordered gold nanoring arrays were prepared by ion-sputtering method and used as surface enhanced Raman spectroscopy (SERS) substrates to test the individual atmospheric aerosols particle. Compared to other methods used for testing atmospheric aerosols particles, the collection and subsequent detection in our work is performed directly on the gold nanoring SERS substrate without any treatment of the analyte. The SERS performance can be tuned by changing the depth of the gold nanoring cavity as originating from coupling of dipolar modes at the inner and outer surfaces of the nanorings. The electric field exhibits uniform enhancement and polarization in the ordered Au nanoring substrate, which can improve the accuracy for detecting atmospheric aerosol particles. Combined with Raman mapping, the information about chemical composition of individual atmospheric aerosols particle and distribution of specific components can be presented visually. The results show the potential of SERS in enabling improved analysis of aerosol particle chemical composition, mixing state, and other related physicochemical properties.     

Noble metal catalysts for methane removal

Using a bench-scale rig, the activities of Pt, Pd and Pt+Pd catalysts supported on gamma-Al(2)O(3) and on TiO(2) (anatase) for the complete oxidation of methane (300 ppmv) in air have been measured as a function of temperature; values of T(10), T(50) and T(90) together with the Arrhenius parameters (activation energy and pre-exponential factor) are reported. Pt is less active than Pd when deposited on the surface of the TiO(2), but more active when deposited on gamma-Al(2)O(3), however when combined, the Pt+Pd mixture is more active than either metal individually. The T(10) for Pt+Pd/gamma-Al(2)O(3) was being as low as 228 degrees C. The significance of the Arrhenius parameters, for metal containing catalysts is that they exhibit compensation with increasing activation energy, while securing a more rapid increase in conversion from 0% to 100% when the temperature is increased.     

Use of constructed wetland for the removal of heavy metals from industrial wastewater

This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW.     

The Process Analysis Method of selecting indicators to quantify the sustainability performance of a business operation

This paper describes a method for assessing the degree of sustainability of a business operation, in terms of indicators related to the sustainability impacts of its particular activities. The Process Analysis Method considers the impact on the capital residing in the three domains: the environment, the economy and the domain of human/social capital. It is found, using the Brundtland definition of sustainability, that these impacts can be related to two business perspectives: (1) Resource efficiency, which measures the effectiveness of conversion of natural, financial, human and social capital; (2) Fairness in benefit which describes how fairly the benefits and disbenefits of changes in the three domains are distributed amongst stakeholders.The method requires a complete review of the activities of the business within an appropriately defined system boundary, in order to make an inventory of activities which affect the capital stores of value; those effects are found to relate to the business perspectives. The effects of these activities on stakeholders are identified, and those which are deemed to be significant are characterised by issues: these determine the selection of indicators whose values are given by metrics. The methodology thus enables the development of a comprehensive set of sustainability indicators and metrics for the particular business operation. The set of indicators will be similar for businesses with similar activities, so the methodology facilitates comparison and benchmarking. Further, the value of a particular indicator can be traced back through the analysis to a particular business process, which is especially helpful in guiding remedial action, since cause is linked to effect by the method.     

Therapeutic role of garlic and vitamins C and E against toxicity induced by lead on various organs

Environmental Science and Pollution Research - Due to industrial and urban sewage, the metal contaminations in aquatic and terrestrial environments are increasing day by day, especially in...     

Sandbar-regulated hydrodynamic influences on river hydrochemistry at Mengabang Telipot River, Peninsular Malaysia

Influences of river hydrodynamic behaviours on hydrochemistry (salinity, pH, dissolved oxygen saturations and dissolved phosphorus) were evaluated through high spatial and temporal resolution study of a sandbar-regulated coastal river. River hydrodynamic during sandbar-closed event was characterized by minor dependency on tidal fluctuations, very gradual increase of water level and continual low flow velocity. These hydrodynamic behaviours established a hydrochemistry equilibrium, in which water properties generally were characterized by virtual absence of horizontal gradients while vertical stratifications were significant. In addition, the river was in high trophic status as algae blooms were visible. Conversely, river hydrodynamic in sandbar-opened event was tidal-controlled and showed higher flow velocity. Horizontal gradients of water properties became significant while vertically more homogenised and with lower trophic status. In essence, this study reveals that estuarine sandbar directly regulates river hydrodynamic behaviours which in turn influences river hydrochemistry.     

The impact of financial development and globalization on environmental quality: evidence from South Asian economies

Environmental Science and Pollution Research - Climate change resulting from the higher concentration of greenhouse gases in the atmosphere is a threat to the sustainability of life on earth. To...     

Correction to: Health risk assessment of hexachlorocyclohexane in soil,water and plants in the agricultural area of Potohar region,Punjab, Pakistan

Environmental Geochemistry and Health - A correction to this paper has been published: https://doi.org/10.1007/s10653-021-00910-5     

Determination of pesticide residues in fruits and vegetables in Islamabad market

Pesticide residues in fruits and vegetable from Islamabad market, Pakistan were determined by GLC using Perkin Elmer Autosystem equipped with 63NECD and capillary column. Dimethoate was determined in the quantity of 0.032 mg kg-1 in apple, 0.110 mg kg-1 in banana, 0.004 mg kg-1 in brinjal, 1.80 mg kg-1 in cauliflower and 0.13 mg kg-1 in arvi, fenvalerate 0.010 mg kg-1 in apple and chlorpyrifos 0.004 mg kg-1 in brinjal. The importance of these pesticide residues with reference to human health is also briefly discussed.     

Evaluation of Generic Types of Drilling Fluid Using a Risk-Based Analytic Hierarchy Process

The composition of drilling muds is based on a mixture of clays and additives in a base fluid. There are three generic categories of base fluid - water, oil, and synthetic. Water-based fluids (WBFs) are relatively environmentally benign, but drilling performance is better with oil-based fluids (OBFs). The oil and gas industry developed synthetic-based fluids (SBFs), such as vegetable esters, olefins, ethers, and others, which provide drilling performance comparable to OBFs, but with lower environmental and occupational health effects. The primary objective of this paper is to present a methodology to guide decision-making in the selection and evaluation of three generic types of drilling fluids using a risk-based analytic hierarchy process (AHP). In this paper a comparison of drilling fluids is made considering various activities involved in the life cycle of drilling fluids.This paper evaluates OBFs, WBFs, and SBFs based on four major impacts—operations, resources, economics, and liabilities. Four major activities—drilling, discharging offshore, loading and transporting, and disposing onshore—cause the operational impacts. Each activity involves risks related to occupational injuries (safety), general public health, environmental impact, and energy use. A multicriteria analysis strategy was used for the selection and evaluation of drilling fluids using a risk-based AHP. A four-level hierarchical structure is developed to determine the final relative scores, and the SBFs are found to be the best option.