Assessment of bioavailability of some potential toxic metals in mining-affected soils using EDTA extraction and principle component analysis (PCA) approach, Derbyshire, UK

The current study area has long mining history for copper, lead, and zinc. As a result, these metals may have elevated levels and pose a potential risk to the surrounding area. This area is currently being used for agriculture and sheep rearing, therefore, the bioavailable fraction of some selected heavy metals namely (Cu, Pb, Zn, Mn, Cr, Ni, and V) has been evaluated using 0.01 M EDTA procedure, as this would help for better understanding of the risk that these heavy metals can pose to living organisms. A total of 51 samples of topsoils, floodplain soils, and stream sediment soils were collected and analysed for their total concentrations using ICP (Inductively Coupled Plasma) optical emission spectroscopy. Results show that, depending on the bioavailable ratio, soil samples have the biggest EDTA extractable amount for all studied metals, except for Mn and Cr for which highest levels were found in the floodplain samples. However, based on national bioavailable mean amount in England and Wales, the amount of EDTA metal extractable for all selected metals from soil samples are exceeded the national average amounts of England and Wales, except for Mn and Ni, whereas in floodplain and stream sediment samples, all EDTA metals extractions are lower than the national mean levels, except Cu and Zn for flood plan samples. Principal component analysis (PCA) technique was performed to investigate how the bioavailable fractions of studied metals and factors namely (organic matter contents, soil pH, and different granulometric ranges) are correlated. Results show that both organic matter amounts and fine fractions (clay and silt) were the master factors controlling the bioavailable portion in all soil types

Noncommunicable diseases and risk of hospitalisation in Kuwait: a generalisable approach using the population-based World Health Survey

Kuwait and countries in the Arabian Gulf region face an alarming prevalence of noncommunicable diseases (NCDs) that strains their health systems and threatens their economies, exacting far-reaching health and economic tolls. To that end, we estimated the increased risk of hospitalisation associated with diagnoses of most prevalent NCDs in Kuwait using a generalisable approach to establish cross-country disease burden comparisons and effective mitigation metrics. The study analysed responses from a nationally representative sample of 2,165 individuals that self-reported the number of hospitalisations in the last 12-months and NCD diagnoses from the World Health Survey (WHS) – Kuwait 2010. Hospitalisation rates were examined for individuals diagnosed with hypertension, diabetes mellitus, asthma, chronic lung condition, heart disease or angina, and stroke. Through group comparisons and statistical models, we found that hypertension, the most common NCD in Kuwait, was associated with a 75 percent increase in hospital admissions. In addition, heart disease was associated with a 495 percent increase in the risk of hospital admission after adjusting for potential confounders. Elevated hospitalisation risks associated with NCDs call for an urgent shift of resources to mitigate the subsequent morbidity, mortality, and burden on Kuwait’s curative health services. We estimated the substantial burden on curative services associated with NCDs in Kuwait through a readily available, standardised approach to compare hospitalisation rates related to NCDs across over 70 countries that participated in the WHS

Influence of Sleep Pattern and Oral Hydration on Academic Performance among Undergraduate Dental Students-A Pilot Study

Sound sleep is important for preserving good physical, mental, and emotional health. An association with learning skills, critical decision making and thinking is also observed [1]. Poor hydration is associated with several health outcomes including poor oral health and academic performance. Timely assessment of oral hydration of students holds a potential to improve their oral health and academic performance [1, 2]. This study is designed to investigate the influence of oral hydration status and sleep deprivation on academic achievements of dental college undergraduate

Extraction of phosphoric acid from various aqueous solutions using tributyl phosphate (TBP)

Solvent extraction of phosphoric acid from various aqueous solutions has been investigated using tributyl phosphate in kerosene as the extractant. The effect of the nature of the diluent on the extraction of phosphoric acid with TBP has been studied and correlated with the dielectric constant. The extraction equilibrium curve showed that an overall extraction yield of more than 80 % could be reached from aqueous solutions containing 0.8M of sulfuric acid. Pure phosphoric acid was stripped from the loaded organic phase by counter current stripping with distilled water. The produced acid was post treated to eliminate the co-extracted acids and characterized

Geometry of 2-Weierstrass points on certain plane curves

学位記号番号 : 博理工甲第780号博士の専攻分野の名称 : 博士(学術) 学位授与年月日 : 平成22年3月24日textapplication/pdfthesi

Counter current extraction of phosphoric acid: food grade acid production

Extraction, scrubbing and stripping of phosphoric acid from the Syrian wet-phosphoric acid was carried out using Micro-pilot plant of mixer-settler type of 8 l/h capacity. Tributyl phosphate (TBP)/di-isopropyl ether (DIPE) in kerosene was used as extractant. Extraction and stripping equilibrium curves were evaluated. The number of extraction and stripping stages to achieve the convenient and feasible yield was determined. Detailed flow sheet was suggested for the proposed continuous process. Data obtained include useful information for the design of phosphoric acid extraction plant. The produced phosphoric acid was characterized using different analytical techniques

Analysis of factors affecting uranium stripping from DEHPA/dodecane using FTIR and other analytical methods

Uranium(VI) is stripped from 0.1 mol.l-1 DEHPA/dodecane using different concentration of phosphoric acid. This study investigates the main operating variables, mainly phosphoric acid concentration used as a strip solution, and temperature. Infrared spectra of the stripped organic were investigated in region of P=O stretching vibration to represent the effect of the previous variables on uranium stripping and compared with other conventional analytical methods. Results showed that concentration of the strip solution is effective in the range of 5-18 wt% P2O5 at fixed temperature, and the temperature effect is less than the strip solution concentration effect by the factor of 1/6. Results obtained enable us to choose the suitable temperature and wt% P2O5 of the strip solution to evaluate the demanded stripping distribution ratio

Solvent extraction of Vanadium (IV) with di(2-ethylhexyl) phosphoric acid and tributyl phosphate

Vanadium pregnant solution recovered from the Syrian Petroleum coke by means of salt roasting was acidified by dilute sulfuric acid. Solvent extraction of tetravalent vanadium with a mixture of di(2-ethylhexyl) phosphoric acid (DEHPA) and Tributylphosphate (TBP) was carried out. Kinetic effects are involved in competitive extraction of other metals such as iron and aluminum