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1.
Bioresour Technol ; 99(5): 1325-31, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17383868

RESUMEN

In the present study, effect of adsorbent dose, pH and agitation speed on nickel removal from aqueous medium using an agricultural waste biomass, Sugarcane bagasse has been investigated. Batch mode experiments were carried out to assess the adsorption equilibrium. The influence of three parameters on the removal of nickel was also examined using a response surface methodological approach. The central composite face-centered experimental design in response surface methodology (RSM) by Design Expert Version 6.0.10 (Stat Ease, USA) was used for designing the experiments as well as for full response surface estimation. The optimum conditions for maximum removal of nickel from an aqueous solution of 50 mg/L were as follows: adsorbent dose (1500 mg/L), pH (7.52) and stirring speed (150 rpm). This was evidenced by the higher value of coefficient of determination (r(2)=0.9873).


Asunto(s)
Agricultura , Biomasa , Níquel/química , Eliminación de Residuos Líquidos/métodos , Adsorción , Concentración de Iones de Hidrógeno , Residuos Industriales , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/química
2.
J Hazard Mater ; 140(1-2): 60-8, 2007 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-16879918

RESUMEN

In the present study adsorption of Cr(VI) from aqueous solutions onto different agricultural wastes, viz., sugarcane bagasse, maize corn cob and Jatropha oil cake under various experimental conditions has been studied. Effects of adsorbent dosage, Cr(VI) concentration, pH and contact time on the adsorption of hexavalent chromium were investigated. The concentration of chromium in the test solution was determined spectrophotometrically. FT-IR spectra of the adsorbents (before use and after exhaustion) were recorded to explore number and position of the functional groups available for the binding of chromium ions on to studied adsorbents. SEMs of the adsorbents were recorded to explore the morphology of the studied adsorbents. Maximum adsorption was observed in the acidic medium at pH 2 with a contact time of 60min at 250rpm stirring speed. Jatropha oil cake had better adsorption capacity than sugarcane bagasse and maize corn cob under identical experimental conditions. The applicability of the Langmuir and Freundlich adsorption isotherms was tested. The results showed that studied adsorbents can be an attractive low cost alternative for the treatment of wastewaters in batched or stirred mode reactors containing lower concentrations of chromium.


Asunto(s)
Biomasa , Cromo/aislamiento & purificación , Productos Agrícolas , Residuos Peligrosos , Contaminantes del Agua/aislamiento & purificación , Adsorción , Reactores Biológicos , Concentración de Iones de Hidrógeno , Saccharum , Zea mays
3.
Appl Spectrosc ; 71(11): 2532-2537, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28485655

RESUMEN

Pneumonia is an acute lung infection that takes life of many young children in developing countries. Early stage (red hepatization) detection of pneumonia would be pragmatic to control mortality rate. Detection of this disease at early stages demands the knowledge of pathology, making it difficult to screen noninvasively. We propose photoacoustic spectral response (PASR), a noninvasive elasticity-dependent technique for early stage pneumonia detection. We report the quantitative red hepatization detection of pneumonia through median frequency, spectral energy, and variance. Significant contrast in spectral parameters due to change in sample elasticity is found. The tissue-mimicking phantom study illustrates a 39% increase in median frequency for 1.5 times the change in density. On applying to formalin-fixed pneumonia-affected goat lungs, it provides a distinct change in spectral parameters between pneumonia affected areas and normal lungs. The obtained PASR results were found to be highly correlating to standard histopathology. The proposed technique therefore has potential to be a regular diagnostic tool for early pneumonia detection.


Asunto(s)
Pulmón/patología , Técnicas Fotoacústicas/métodos , Neumonía/diagnóstico , Animales , Fenómenos Biomecánicos , Diagnóstico por Imagen de Elasticidad/instrumentación , Diagnóstico por Imagen de Elasticidad/métodos , Diseño de Equipo , Cabras , Fantasmas de Imagen , Técnicas Fotoacústicas/instrumentación
4.
Int Immunopharmacol ; 4(13): 1709-22, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15454122

RESUMEN

Haemato- biochemical and immuno-pathophysiological changes following feeding of broiler chicks with 20 ppm fenvalerate (synthetic pyrethroid, SP), 2 ppm monocrotophos (organophosphate, OP) and 2 ppm endosulfan (chlorinated hydrocarbon, CH) were studied. Four groups of broiler birds (30 each) were fed poultry mash without (control) or mixed with pesticides for 8 weeks. Blood glucose, serum globulin and acetyl cholinesterase (AChE) activity level were decreased (P<0.01) in all treated groups compared to control, but not the serum albumin and BUN. The total ATPase activity was enhanced (P<0.01) in fenvalerate and monocrotophos than birds in control group. Body weight, total erythrocyte count, packed cell volume, haemoglobin, eosinophil and monocyte count did not show any changes. Total leucocytes and T-lymphocyte count was lower (P<0.01) in all treated groups as compared to control group. B-cell count (P<0.01), mean 2-4-dinitrofluorobenzene (DNFB) dermal sensitivity score and splenic indices from graft vs. host reaction (P<0.05) were decreased in fenvalarate and endosulfan but the values for monocrotophos were intermediate between control and other treated groups. Pesticide intoxication reduced nitroblue tetrazolium (NBT) positive cells (active splenic macrophages) (P<0.05) and spleen weight (P<0.01). Whereas bursal weight was reduced only with endosulfan, thymic weight was reduced on endosulfan and fenvalerate-treated feed. Microscopic examination of these organs further revealed atrophy/hypoplasia, decrease in the size of follicles with depletion of lymphocytes and haemorrhages in thymus. The study concludes that the chronic exposure of chicks to small amount of SP, OP and CH pesticide leads to deleterious effects on metabolism and immune system of birds.


Asunto(s)
Sistema Inmunológico/fisiopatología , Insecticidas/toxicidad , Organofosfatos/toxicidad , Aves de Corral/sangre , Piretrinas/toxicidad , Pruebas de Toxicidad Crónica/métodos , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Peso Corporal/efectos de los fármacos , Dinitrofluorobenceno/toxicidad , Hipersensibilidad a las Drogas/inmunología , Endosulfano/toxicidad , Reacción Injerto-Huésped/efectos de los fármacos , Reacción Injerto-Huésped/inmunología , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/inmunología , India , Insecticidas/sangre , Insecticidas/inmunología , Tejido Linfoide/efectos de los fármacos , Tejido Linfoide/inmunología , Tejido Linfoide/ultraestructura , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Nitrilos/sangre , Nitrilos/química , Nitrilos/inmunología , Nitroazul de Tetrazolio/farmacología , Tamaño de los Órganos/efectos de los fármacos , Organofosfatos/química , Organofosfatos/inmunología , Bifenilos Policlorados/sangre , Bifenilos Policlorados/química , Bifenilos Policlorados/inmunología , Aves de Corral/anatomía & histología , Aves de Corral/inmunología , Piretrinas/sangre , Piretrinas/síntesis química , Piretrinas/química , Piretrinas/inmunología , Piel/efectos de los fármacos , Piel/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología
5.
Toxicol Pathol ; 32(3): 364-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15204980

RESUMEN

This experiment evaluated effects following chronic toxicity with 20 ppm fenvalerate (synthetic pyrethroid), 2 ppm monocrotophos (organophosphate) and 2 ppm endosulfan (chlorinated hydrocarbon) on bone health of broiler chicks. A total of 120 chicks were divided equally into 4 groups and were fed poultry mash without (control) or mixed with different pesticides for 8 weeks. Body mass, serum calcium and phosphorus levels were unaffected due to pesticides treatment. However, increase an (p < 0.01) in serum alkaline phosphatase activity was noted and serum total protein decreased (p < 0.01) in all treated groups. Roentogenography revealed destructive changes in the upper part of the femur in the monocrotophos group. Endosulfan intoxicated chicks had increased numbers of trabeculae in the medullary cavity. Microscopic alterations of the costochondral junction in intoxicated chicks were similar. The zones of proliferating, maturing and degenerating, and calcifying cartilage cells were reduced in width and the metaphysis in treated birds showed a reduced number of cartilage cells and thinner trabeculae. Due to toxicity, the capillary scaffolding of the degenerating cartilage cells was reduced and a larger number of transverse trabeculae could be seen in the metaphysis. Appositional bone growth studied by the tetracyclicline labeling technique indicated decreased active osteons.


Asunto(s)
Huesos/efectos de los fármacos , Pollos , Hidrocarburos Clorados/toxicidad , Plaguicidas/toxicidad , Enfermedades de las Aves de Corral/fisiopatología , Piretrinas/toxicidad , Animales , Desarrollo Óseo/efectos de los fármacos , Huesos/patología , Calcio/sangre , Endosulfano/toxicidad , Fémur/efectos de los fármacos , Fémur/patología , Monocrotofos/toxicidad , Nitrilos , Fósforo/sangre , Enfermedades de las Aves de Corral/inducido químicamente , Enfermedades de las Aves de Corral/patología
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