Evaluation of hydroxyapatite/poly(acrylamide-acrylic acid) for sorptive removal of strontium ions from aqueous solution

Environmental Science and Pollution Research - A composite polymer, hydroxyapatite/poly(acrylamide-acrylic acid), was synthesized by gamma-induced polymerization. The factors affecting the sorption...     

Could curcumin ameliorate titanium dioxide nanoparticles effect on the heart? A histopathological,immunohistochemical, and genotoxic study

Environmental Science and Pollution Research - The evaluation of the toxicological effects of titanium dioxide nanoparticles (TiO2NPs) is increasingly important due to their growing occupational...     

Influence of preparation method on structural,optical, magnetic,and adsorption properties of nano-NiFe2O4

Nickel ferrite (NiFe₂O₄) nanoparticles are prepared through different routes (microwave, co-precipitation, and pyrolysis) and tested for water purification applications through adsorption removal of an acid red dye B as a model organic pollutant. The characterizations of the prepared samples were done using XRD, FT-IR, SEM, TEM, BET, UV-Vis absorbance, Raman spectrum, and vibrating sample magnetometer (VSM). All samples showed an inverse spinel crystal structure. The obtained results pointed out to the effect of the synthetic route on the morphology, particle size, optical, and magnetic properties of the prepared ferrites. Magnetic measurements showed super-paramagnetic behavior for all samples. The magnetic saturation (M_s) of the sample prepared by pyrolysis, was found to possess the highest saturation value, 34.8 emu/g. Adsorption experiments were performed under the change in several parameters, such as pH, adsorbent dosage, and initial dye concentration. A dye removal percentage of 99% was reached under the optimum state. The isothermal adsorption of the acid red dye was investigated using several models, in which the experimental data could be best described by the Freundlich model. Several kinetic and equilibrium models were inspected by linear regression analysis and showed best fitting for the adsorption data through pseudo-second-order model. The calculated thermodynamic parameters indicated that the adsorption of acid red dye onto all the ferrite samples is a spontaneous and endothermic physical adsorption process.

     

First inter-laboratory comparison exercise for the determination of anticancer drugs in aqueous samples

The results of an inter-laboratory comparison exercise to determine cytostatic anticancer drug residues in surface water, hospital wastewater and wastewater treatment plant effluent are reported. To obtain a critical number of participants, an invitation was sent out to potential laboratories identified to have the necessary knowledge and instrumentation. Nine laboratories worldwide confirmed their participation in the exercise. The compounds selected (based on the extent of use and laboratories capabilities) included cyclophosphamide, ifosfamide, 5-fluorouracil, gemcitabine, etoposide, methotrexate and cisplatinum. Samples of spiked waste (hospital and wastewater treatment plant effluent) and surface water, and additional non-spiked hospital wastewater, were prepared by the organising laboratory (Jo?ef Stefan Institute) and sent out to each participant partner for analysis. All analytical methods included solid phase extraction (SPE) and the use of surrogate/internal standards for quantification. Chemical analysis was performed using either liquid or gas chromatography mass (MS) or tandem mass (MS/MS) spectrometry. Cisplatinum was determined using inductively coupled plasma mass spectrometry (ICP-MS). A required minimum contribution of five laboratories meant that only cyclophosphamide, ifosfamide, methotrexate and etoposide could be included in the statistical evaluation. z-score and Q test revealed 3 and 4 outliers using classical and robust approach, respectively. The smallest absolute differences between the spiked values and the measured values were observed in the surface water matrix. The highest within-laboratory repeatability was observed for methotrexate in all three matrices (CV?≤?12 %). Overall, inter-laboratory reproducibility was poor for all compounds and matrices (CV 27–143 %) with the only exception being methotrexate measured in the spiked hospital wastewater (CV?=?8 %). Random and total errors were identified by means of Youden plots.     

The potentials of internalising social banking among the Malaysian Islamic banks

Islamic banking has established for the last 40 years, yet only recently researchers acknowledge social failures of Islamic banking and finance. This has led to a proposition of forming new forms of banking and non-banking institutions that include social banking. It is argued that in considering the developmentalist needs of the Muslim societies in Malaysia, there is a need to go back to fundamentals of Islamic finance in realising the aspirational Islamic moral economy that emphasises on the social good, capacity development at the individual and social levels. This paper aims to explore the concept of social banking and search for the possibilities for internalisation in Malaysian Islamic banking. To gain understanding on this pertinent issue, an empirical investigation was conducted at 17 Islamic banks in Malaysia. A mixed method was employed. For the primary data collection, 477 respondents of Islamic banks clients and employees participated in a self-administrated survey, and 11 respondents from the executive and managerial level of eight Islamic banks involved in a semi-structured interview survey. The integrated analysis implies that Islamic banking significantly contributes to socio-economic development. On the contrary, financial and economic practices in everyday life do not reflect the social economic justice. The result further illustrates that the Islamic banks lack social contributions as they prone to practice efficiency-oriented institutions. Hence, a social banking model is needed to solve the lack of socio-economic development issue in the current practice of Islamic bank.     

Disposal of obsolete pesticides,the case of Ethiopia

Ethiopia has accumulated obsolete pesticide stocks since pesticides were first imported in the 1960s due to prolonged storage of pesticides, inappropriate storage conditions because of poor storage facilities, the lack of trained staff and lack of national legislation for pesticide registration and monitoring system of pesticide use in the country. The first pesticide inventory conducted in 1995 led by FAO in collaboration with the government of Ethiopia had identified about 426 tonnes of obsolete pesticides mainly on state-owned agricultural farms and held by the Ministry of Health. However, these stocks have increased to over 1500 tonnes (including 200 active ingredients) as found in a detailed inventory conducted in 1999. The stocks included organochlorines (258.3 tonnes), organophosphates (155.4 tonnes), carbamates (58.5 tonnes), coumarines (14.9 tonnes), inorganics (30.2 tonnes), others (257.2 tonnes), mixed pesticides (70.4 tonnes) and unknown pesticides (307.1 tonnes) including both liquid and solid state formulations. The obsolete organochlorine pesticides stocks were mostly pesticides such as chlordane, DDT, dieldrin and lindane that are banned or restricted in most countries. The highest amount of a single active ingredient found was the organophosphate insecticide pirimiphos methyl (172.1 tonnes). All these stocks were disposed of in the first phase of disposal in Finland (during 2000–2003) by the hazardous waste management company Ekokem at a cost of about US$ 4.44 million. Another 1000 tonnes of obsolete pesticides have been identified and are currently being eliminated in a second disposal phase at a total cost of US$ 8 135 500. Along with the disposal process, a number of activities are being implemented to prevent future pesticides accumulation. These activities include the development and enforcement of pesticide policy, the implementation of Integrated Pest Management (IPM) and Integrated Vector Management (IVM), capacity building in terms of providing professional trainings, creating awareness among stakeholders on the environmental and human health hazard posed by obsolete pesticides as well as other actions to prevent their accumulation and enforcement of national legislations and policies related to pesticides use. However, pesticide use in the country is increasing. For instance, 12 years of pesticides import data (1996–2007) by the Ministry of Agriculture shows that 2973 tonnes of pesticides were imported between 1996–1998, 3670 tonnes between 1999–2001, 5079 tonnes between 2002–2004 and 8302 tonnes between 2005–2007. Moreover, 6 years of insecticide import data (1996/97–2001/02) by the Ministry of Health shows that around 919 tonnes of insecticides were imported between 1996/97–1997/98, 812 tonnes between 1998/99–1999/00 and 970 tonnes between 2000/01–2001/02 for malaria and other vector borne diseases control.     

Kinetics of carbon dioxide absorption into mixed aqueous solutions of MDEA and MEA using a laminar jet apparatus and a numerically solved 2D absorption rate/kinetics model

New comprehensive numerically solved 1D and 2D absorption rate/kinetics models have been developed, for the first time, to interpret the experimental kinetic data obtained with a laminar jet apparatus for the absorption of carbon dioxide (CO₂) in CO₂ loaded mixed solutions of mixed amine system of methyldiethanolamine (MDEA) and monoethanolamine (MEA). Three MDEA/MEA weight ratios ranging from 27/03 to 23/07, over a concentration range of 2.316–1.996 kmol/m³ for MDEA and of 0.490–1.147 kmol/m³ for MEA were studied. The models take into account the coupling between chemical equilibrium, mass transfer, and the chemical kinetics of all possible chemical reactions involved in the CO₂ reaction with MDEA/MEA solvent. The partial differential equations of the 1D model were solved by two numerical techniques; the finite difference method (FDM) based on in-house coded Barakat–Clark scheme and the finite element method (FEM) based on COMSOL software. The FEM comprehensive model was then used to solve the set of partial differential equations in the 2D cylindrical coordinate system setting. Both FDM and FEM produced very accurate results for both the 1D and 2D models, which were much better than our previously published simplified model. The reaction rate constant obtained for MEA blended into MDEA at 298–333 K was k_MEA = 5.127 × 10⁸ exp(−3373.8/T). In addition, the 2D model, for the first time, has provided the concentration profiles of all the species in both the radial and axial directions of the laminar jet, thereby enabling an understanding of the correct sequence in which the reaction steps involved in the reactive absorption of CO₂ in aqueous mixed amines occur.     

Environmental Assessments in the Oil and Gas Industry

The general public, government regulators, and environmental organizations are increasingly demanding industries to reduce their environmental impacts and report progress. This in turn resulted in numerous requirements for reporting environmental data. Environmental assessments are a useful tool in gathering and documenting this data. The assessments also assist decision makers to quantify impacts of their activities and plan for appropriate mitigation measures. There are different types of environmental assessments, each having specific purpose(s) and addressing specific audience(s). This paper gives an overview of common environmental concerns associated with oil and gas industry and shares insights on types of environmental assessments that are widely used. It discusses general methodologies to define the scope, approach, measurement standards, and reporting. Potential challenges encountered in conducting these assessments in an international arena and under a wide variety of regulatory requirements are addressed. Practical approach in execution of these assessments is described here, and strategy in dealing with the challenges is presented.     

Development of an integrated sensor to measure odors

Odorous air samples collected from several sources were presented to an olfactometer, an electronic nose, a hydrogen sulfide (H(2)S) detector and an ammonia (NH(3)) detector. The olfactometry measurements were used as the expected values while measurements from the other instrumentation values became input variables. Five hypotheses were established to relate the input variables and the expected values. Both linear regression and artificial neural network analyses were used to test the hypotheses. Principal component analysis was utilized to reduce the dimensionality of the electronic nose measurements from 33 to 3 without significant loss of information. The electronic nose or the H(2)S detector can individually predict odor concentration measurements with similar accuracy (R (2) = 0.46 and 0.50, respectively). Although the NH(3) detector alone has a very poor relationship with odor concentration measurements, combining the H(2)S and NH(3) detectors can predict odor concentrations more accurately (R (2) = 0.58) than either individual instrument. Data from the integration of the electronic nose, H(2)S, and NH(3) detectors produce the best prediction of odor concentrations (R (2) = 0.75). With this accuracy, odor concentration measurements can be confidently represented by integrating an electronic nose, and H(2)S and NH(3) detectors.     

Arsenic in shallow aquifer in the eastern region of Bangladesh: insights from principal component analysis of groundwater compositions

Probable sources and mechanisms of arsenic (As) release in shallow aquifer in eastern Bangladesh are evaluated using statistical analysis of groundwater compositions. Dissolved As in 39 samples ranged from 8.05 to 341.5 μg/L with an average of 95.14 μg/L. Ninety seven percent of wells exceed the WHO limit (10 μg/L) for safe drinking water. Principal component analysis is applied to reduce 16 measured compositional variables to five significant components (principal components—PCs) that explain 86.63% of the geochemical variance. Two component loadings, namely PC 1 and PC 2 (45.31% and 23.05%) indicate the natural processes within the aquifers in which organic matter is a key reactant in the weathering reactions. Four groups of wells are defined by the PCA and each group of wells represents distinct physicochemical characteristics. Among them, group III groundwater shows higher As concentration together with high concentrations of Fe, Mn, dissolved organic carbon, $\text{PO}_{4}^{3-}$ and $\text{HCO}_{3}^{-}$ than groups I and II. Speciation calculations suggest that only wells of group III are saturated with respect to siderite, and all groups of samples are supersaturated with respect of rhodochrosite. The relationship of As with these parameters in the different groups of wells of the study area suggests that reductive dissolution of Fe–Mn oxyhydroxides with microbially mediated degradation of organic matter is considered to be the dominant processes to release As in groundwater.