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Search Results: 1 - 10 of 238684 matches for " Alam G.;Silva "
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Degradation of the herbicide paraquat by photo-fenton process: optimization by experimental design and toxicity assessment
Trovó, Alam G.;Gomes Junior, Oswaldo;Machado, Antonio E. H.;Borges Neto, Waldomiro;Silva, Jader O.;
Journal of the Brazilian Chemical Society , 2013, DOI: 10.1590/S0103-50532013000100011
Abstract: this study describes the influence and optimization of fenton's reagent (concentration of fe2+ and h2o2 ) on the efficiency of mineralization of the herbicide paraquat (pqt, 50 mg l-1) in water, after 60 min (equivalent to 642 kj l-1 of accumulated uva radiation) treatment by photo-fenton process in laboratory scale, using central composite design (ccd). under optimized conditions, kinetic experiments were done, evaluating the pqt removal, its mineralization and toxicity in laboratory scale, using artificial irradiation, and in a pilot plant under solar irradiation. the same removal efficiency and mineralization of pqt were obtained in both reactors. the toxicity of the samples, estimated in terms of mortality of artemia salina, decreases simultaneously with the decay of concentration of pqt, suggesting the formation of intermediates of lower toxicity. in this way, the solar photo-fenton process can be considered as a viable alternative for the treatment of wastewater containing pqt.
Fundamentos e aplica??es ambientais dos processos fenton e foto-fenton
Nogueira, Raquel F. Pupo;Trovó, Alam G.;Silva, Milady Renata A. da;Villa, Ricardo D.;Oliveira, Mirela C. de;
Química Nova , 2007, DOI: 10.1590/S0100-40422007000200030
Abstract: wastewater and soil treatment processes based on fenton's reagent have gained great attention in recent years due to its high oxidation power. this review describes the fundaments of the fenton and photo-fenton processes and discusses the main aspects related to the degradation of organic contaminants in water such as the complexation of iron, the use of solar light as the source of irradiation and the most important reactor types used. an overview of the main applications of the process to a variety of industrial wastewater and soil remediations is presented.
Higher estimates of daily dietary net endogenous acid production (NEAP) in the elderly as compared to the young in a healthy, free-living elderly population of Pakistan
Alam I, Alam I, Paracha PI, Pawelec G
Clinical Interventions in Aging , 2012, DOI: http://dx.doi.org/10.2147/CIA.S37158
Abstract: her estimates of daily dietary net endogenous acid production (NEAP) in the elderly as compared to the young in a healthy, free-living elderly population of Pakistan Original Research (847) Total Article Views Authors: Alam I, Alam I, Paracha PI, Pawelec G Published Date December 2012 Volume 2012:7 Pages 565 - 573 DOI: http://dx.doi.org/10.2147/CIA.S37158 Received: 21 August 2012 Accepted: 24 October 2012 Published: 12 December 2012 Iftikhar Alam,1,2 Ibrar Alam,3 Parvez I Paracha,4 Graham Pawelec2 1Department of Agriculture, Bacha Khan University Charsadda, Khyber Pakhtunkhwa (KPK), Pakistan; 2Tübingen Aging and Tumor Immunology Group, Zentrum für Medizinische Forschung, University of Tübingen, Tübingen, Germany; 3Institute of Bio-technology and Genetics Engineering (IBGE), KPK Agricultural University, Peshawar, Pakistan; 4Department of Human Nutrition, KPK Agricultural University, Peshawar, KPK, Pakistan Abstract: Dietary intake has been shown to influence the acid–base balance in human subjects; however, this phenomenon is poorly understood and rarely reported for the least well-studied segment of older people in a developing country. The aims of the present study were to: (1) quantify estimates of daily net endogenous acid production (NEAP) (mEq/d) in a sample of otherwise healthy elderly aged 50 years and above; and (2) compare NEAP between the elderly and young to determine the effects of aging, which could contribute to changes in the acid–base balance. Analyses were carried out among 526 elderly and 131 young participants (aged 50–80 and 23–28 years, respectively), all of whom were free of discernible disease, nonsmokers, and not on any chronic medication. Selected anthropometric factors were measured and 24-hour dietary recall was recorded. We used two measures to characterize dietary acid load: (1) NEAP estimated as the dietary potential renal acid load plus organic acid excretion, the latter as a multiple of estimated body surface area; and (2) estimated NEAP based on protein and K. For the young and elderly, the ranges of NEAP were 12.1–67.8 mEq/d and 2.0–78.3 mEq/d, respectively. Regardless of the method used, the mean dietary acid–base balance (NEAP) was significantly higher for the elderly than the young (P = 0.0035 for NEAP [elderly, 44.1 mEq/d versus young 40.1 mEq/d]; and P = 0.0035 for the protein:potassium ratio [elderly, 1.4 mEq/d versus young 1.1 mEq/d]). A positive and significant correlation was found between NEAP and energy, protein, and phosphorus (P < 0.05 for all trends). The findings from this study provide evidence of the relatively higher production of NEAP in older people, possibly as an effect of higher consumption of certain acid-producing foods by the elderly.
Higher estimates of daily dietary net endogenous acid production (NEAP) in the elderly as compared to the young in a healthy, free-living elderly population of Pakistan
Alam I,Alam I,Paracha PI,Pawelec G
Clinical Interventions in Aging , 2012,
Abstract: Iftikhar Alam,1,2 Ibrar Alam,3 Parvez I Paracha,4 Graham Pawelec21Department of Agriculture, Bacha Khan University Charsadda, Khyber Pakhtunkhwa (KPK), Pakistan; 2Tübingen Aging and Tumor Immunology Group, Zentrum für Medizinische Forschung, University of Tübingen, Tübingen, Germany; 3Institute of Bio-technology and Genetics Engineering (IBGE), KPK Agricultural University, Peshawar, Pakistan; 4Department of Human Nutrition, KPK Agricultural University, Peshawar, KPK, PakistanAbstract: Dietary intake has been shown to influence the acid–base balance in human subjects; however, this phenomenon is poorly understood and rarely reported for the least well-studied segment of older people in a developing country. The aims of the present study were to: (1) quantify estimates of daily net endogenous acid production (NEAP) (mEq/d) in a sample of otherwise healthy elderly aged 50 years and above; and (2) compare NEAP between the elderly and young to determine the effects of aging, which could contribute to changes in the acid–base balance. Analyses were carried out among 526 elderly and 131 young participants (aged 50–80 and 23–28 years, respectively), all of whom were free of discernible disease, nonsmokers, and not on any chronic medication. Selected anthropometric factors were measured and 24-hour dietary recall was recorded. We used two measures to characterize dietary acid load: (1) NEAP estimated as the dietary potential renal acid load plus organic acid excretion, the latter as a multiple of estimated body surface area; and (2) estimated NEAP based on protein and K. For the young and elderly, the ranges of NEAP were 12.1–67.8 mEq/d and 2.0–78.3 mEq/d, respectively. Regardless of the method used, the mean dietary acid–base balance (NEAP) was significantly higher for the elderly than the young (P = 0.0035 for NEAP [elderly, 44.1 mEq/d versus young 40.1 mEq/d]; and P = 0.0035 for the protein:potassium ratio [elderly, 1.4 mEq/d versus young 1.1 mEq/d]). A positive and significant correlation was found between NEAP and energy, protein, and phosphorus (P < 0.05 for all trends). The findings from this study provide evidence of the relatively higher production of NEAP in older people, possibly as an effect of higher consumption of certain acid-producing foods by the elderly.Keywords: aging, dietary acid-loads, NEAP, vegetables, fruits
Trousseau’s sign  [PDF]
Anwar Alam
Case Reports in Clinical Medicine (CRCM) , 2013, DOI: 10.4236/crcm.2013.25087
Abstract: The trousseau’s sign is carpopedal spasm that results from ischemia that is induced by pressure applied to the upper arm. It is a sensitive and specific sign of hypocalcemia. Here the author is sending the short case summary, images of the demonstration of the Trousseau’s sign. This case also had a cluster of seizures induced by hypocalcemia.
Diclofenac abatement using modified solar photo-fenton process with ammonium iron(III) citrate
Trovó, Alam G.;Nogueira, Raquel F. P.;
Journal of the Brazilian Chemical Society , 2011, DOI: 10.1590/S0103-50532011000600005
Abstract: the influence of ph on the degradation of the pharmaceutical diclofenac (dcf) by the solar/photo-fenton process was investigated using ammonium iron(iii) citrate complex (fecitnh4). although the degradation efficiency decreased as the ph increased (in the ph range 5 to 8), the dcf concentration was lower than its limit of detection after 45 min irradiation while 77% of the total organic carbon was removed after 150 min irradiation at initial ph 7 (without further adjustment). a pseudo-first-order kinetics of dcf degradation was observed, which kinetic constant increased with the increase of the concentrations of fecitnh4 and h2o2. lower dcf degradation was observed when present in a sewage treatment plant (stp) effluent sample, mainly due to the high concentration of carbonate and bicarbonate at ph 7. however, after adjusting the ph to 5, the dcf concentration was lower than its detection limit after 75 min irradiation.
Two Dimensional Hydrodynamic Modelling of Northern Bay of Bengal Coastal Waters  [PDF]
Misbah Uddin, Jahir Bin Alam, Zahirul Haque Khan, G. M. Jahid Hasan, Tauhidur Rahman
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2014, DOI: 10.4236/cweee.2014.34015
Abstract: Mathematical models have advancement to a point where they are considered to be an effective tool for simulating natural phenomena in coastal regions. This paper discusses the development of Bay of Bengal Model (BoBM), updating of the model with the recent bathymetry and shore line of islands and coastline and upgrading from rectangular grid to finer size of mesh grids by using latest version of MIKE21 FM modeling system. This model is very useful for the hydrodynamic study in the coastal region of Bangladesh. The article also presents the model set-up, boundary conditions and few calibration results of the model. The model applications clearly show the variation of the flow structure, their speed and direction separately for monsoon and dry season around the model area which covers the northern part of Bay of Bengal.
Analyses of Nature of Fault through Production Data  [PDF]
Haijun Fan, Atif Zafar, S. G. Alam, Muhammad Kashif, Asif Mehmood
Open Journal of Yangtze Oil and Gas (OJOGas) , 2017, DOI: 10.4236/ojogas.2017.23014
Abstract: An application of integration of reservoir production data in analysis for nature of fault is presented in this paper. The real data of a Gas Field (namely RS Gas Field) of L-Basin of Pakistan are used. The basic concept behind this work is to enlighten the importance of production data analysis in a broader way like for finding out the nature of fault i.e. conductive or non-conductive and if it is conductive, what is the leakage factor of the fault etc. Normally in the case of fault analysis we rely on geological and geophysical methods to some extent but in some cases where these geological and geophysical methods are not able to reach any final and firm conclusion because of data limitation or any other reason, production data analysis may play a great role in answering the ambiguities regarding any fault/faults present there. This paper describes the successful implementation of reservoir production data analysis in RS Gas Field where the main uncertainties were identified during initial stage of field development when location of new development well was going to be marked. Numbers and locations of well are important factors of Oil and Gas Filed Developments; but specifically, for Gas Field Development, these factors become more crucial as compared to Oil Field Development; so clear knowledge of any heterogeneity, barrier, boundary or fault is necessary to develop a gas field optimally and economically.
Plata, pa o, cacao y clavo: "dinero de la tierra" en la Amazonía portuguesa (c. 1640-1750)
Alam da Silva Lima,Rafael Chambouleyron,Danilo Camargo Igliori
Fronteras de la Historia , 2009,
Abstract: El objetivo de este artículo es discutir cómo la economía y la sociedad de la Amazonía portuguesa colonial (de mediados del siglo XVII a mediados del siglo XVIII) se organizaron a partir de la ausencia de moneda metálica; por otro lado, se analizan las razones que llevaron a la Corona portuguesa a no autorizar la circulación de monedas metálicas y las implicaciones que tuvo esa política en la región.
Passive Scalar Advection in Micro Fluidic Device
M. Shahjalal,G.M. Talukder,G.M. Alam,M.K. Alam
Asian Journal of Mathematics & Statistics , 2011,
Abstract: The dynamics of passive scalar advection has been modeled with a set of partial differential equations. The study of the passive scalar advection in a micro fluidic device has been observed. Numerical simulation of the scalar advection has been established from the model equation. The advection of the diluted fluid inside the micro-device occurred due to the pressure gradient of the fluid. A set of nonlinear partial differential equations has been solved numerically for the advection process. Splitting based technique has been developed to simulate the passively advected scalar field. The technique has been observed that saves computational time, requires less computer memory and workable with large Peclet number.
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