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1.
Sci Total Environ ; 780: 146469, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33774299

RESUMEN

The evolution of computer vision and image processing system paved the way that any technologists can extract quantitative data sets from the visual results of an image. Digital image processing (DIP) technique precisely measures and quantifies the image and eliminates the subjectivity of manual interpretation. DIP is a non-destructive, inexpensive and rapid method that has been used by many researchers in various applications of biofuel. In fuel science, DIP and artificial intelligence (AI) techniques have been successfully applied for the classification of biodiesel, selection of biomass for biofuel production. DIP can be used in the combustion process and its control parameters, gas leakage, monitoring fuel reactant conversion reactions, impurities present and adulteration of fuel, also automation process of a fuel injection system. This review gives an overview of the applications of image processing in fuel science.

2.
Carbohydr Polym ; 225: 115240, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31521287

RESUMEN

Pectin was extracted from the waste custard apple peel using ultrasound technique and optimized the extraction process by RSM. The various significant process parameters such as liquid-solid ratio, ultra-sonication time, temperature and pH of solution were studied in the range of 10-25 mL g-1, 10-30 min, 50-80 °C, and 1-3, respectively. The maximum yield of pectin (8.93%) was attained at the optimum condition of 23.52 mL g-1 of liquid-solid ratio, 18.04  min of ultra-sonication time, 63.22 °C of temperature and 2.3 pH of solution. The extracted and commercially available fresh pectin (for comparison purposes) were characterized by various analytical techniques namely, FTIR, DSC, XRD, SEM, and NMR to evaluate their functional groups, thermal properties, crystallinities, morphological and structural characteristics, respectively. The extracted pectin was a toxic free compound as determined by its anti nutritional property study and about 20 mg/mL of antioxidant presented in it.

3.
Carbohydr Polym ; 174: 103-110, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28821024

RESUMEN

The most influencing factor on dextran production by Weissella cibaria NITCSK4 were screened using Plackett Burman design at 95% confidence limit with higher value of co-efficient of determination (R2) 99.58%. The combined effects of significant factors, namely, sucrose, temperature, dipotassium hydrogen phosphate (K2HPO4) and yeast extract were studied and optimized using Response Surface Methodology (RSM). The input parameters of non-linear models predicted by RSM were subsequently optimized using the genetic algorithm (GA) for obtaining a maximum dextran yield. The maximum yield was obtained with sucrose concentration of 15.78%, yeast extract 1.27%, K2HPO4 1.25%, and at 26°C. The predicted conditions were experimentally validated and 43.79mg/ml of dextran was produced. The dextran yield was 51% higher as compared to unoptimized medium. The molecular weight of resulting dextran produced at 26°C is >2000kDa. The NMR spectroscopic analysis demonstrated that the NITCSK4 produced linear dextran with predominant α (1-6) linkage.


Asunto(s)
Dextranos/biosíntesis , Microbiología Industrial , Weissella/metabolismo , Algoritmos , Medios de Cultivo , Modelos Estadísticos , Peso Molecular , Sacarosa
4.
Prep Biochem Biotechnol ; 47(7): 687-698, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28277946

RESUMEN

In this study, Faujasite (FAU) zeolite was coated on low-cost tubular ceramic support as a separating layer through hydrothermal route. The mixture of silicate and aluminate solutions was used to create a zeolitic separation layer on the support. The prepared zeolite ceramic composite membrane was characterized using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), particle size distribution (PSD), field emission scanning electron microscopy (FESEM), and zeta potential measurements. The porosity of ceramic support (53%) was reduced by the deposition of FAU (43%) zeolite layer. The pore size and water permeability of the membrane were evaluated as 0.179 µm and 1.62 × 10-7 m3/m2 s kPa, respectively, which are lower than that of the support (pore size of 0.309 µm and water permeability of 5.93 × 10-7 m3/m2 s kPa). The permeate flux and rejection potential of the prepared membrane were evaluated by microfiltration of bovine serum albumin (BSA). To study the influences of three independent variables such as operating pressure (68.94-275.79 kPa), concentration of BSA (100-500 ppm), and solution pH (2-4) on permeate flux and percentage of rejection, the response surface methodology (RSM) was used. The predicted models for permeate flux and rejection were further subjected to biobjective genetic algorithm (GA). The hybrid RSM-GA approach resulted in a maximum permeate flux of 2.66 × 10-5 m3/m2 s and BSA rejection of 88.02%, at which the optimum conditions were attained as 100 ppm BSA concentration, 2 pH solution, and 275.79 kPa applied pressure. In addition, the separation efficiency was compared with other membranes applied for BSA separation to know the potential of the fabricated FAU zeolite ceramic composite membrane.


Asunto(s)
Filtración/instrumentación , Membranas Artificiales , Albúmina Sérica Bovina/aislamiento & purificación , Zeolitas/química , Algoritmos , Animales , Bovinos , Permeabilidad , Porosidad , Presión , Agua/química , Difracción de Rayos X
5.
Ultrason Sonochem ; 35(Pt A): 204-209, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27707645

RESUMEN

The objectives of the present work are to extract pectin from industrial waste of Musa balbisiana by ultrasound assisted citric acid mediated extraction method and optimization was done through central composite statistical experimental design under response surface methodology. The outcomes of this study exhibited that, process variables (ultrasound power, pH and extraction time) had considerable influence on the pectin extraction. Second order mathematical equation was constructed to predict the data through regression analysis. The optimal extraction process condition was ultrasound power of 323w, pH of 3.2, extraction time of 27min and SL (solid-liquid) ratio of 1:15g/ml. The mean experimental yield of pectin (8.99±0.018%) was fine accord among predicted yield of pectin (9.02%).


Asunto(s)
Fraccionamiento Químico/métodos , Ácido Cítrico/química , Residuos Industriales , Musa/química , Pectinas/aislamiento & purificación , Ondas Ultrasónicas , Concentración de Iones de Hidrógeno , Pectinas/química , Factores de Tiempo
6.
Ultrason Sonochem ; 34: 525-530, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27773278

RESUMEN

Four factors three level face centered central composite response surface design was employed in this study to investigate and optimize the effect of process variables (liquid-solid (LS) ratio (10:1-20:1ml/g), pH (1-2), sonication time (15-30min) and extraction temperature (50-70°C)) on the maximum extraction yield of pectin from waste Artocarpus heterophyllus (Jackfruit) peel by ultrasound assisted extraction method. Numerical optimization method was adapted in this study and the following optimal condition was obtained as follows: Liquid-solid ratio of 15:1ml/g, pH of 1.6, sonication time of 24min and temperature of 60°C. The optimal condition was validated through experiments and the observed value was interrelated with predicted value.


Asunto(s)
Artocarpus/química , Fraccionamiento Químico/métodos , Frutas/química , Pectinas/aislamiento & purificación , Ondas Ultrasónicas , Residuos/análisis , Concentración de Iones de Hidrógeno , Temperatura , Factores de Tiempo
7.
Int J Biol Macromol ; 72: 1323-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25450551

RESUMEN

Ultrasound assisted extraction of pectin from waste pomegranate peel was investigated and optimized using Box-Behnken response surface design coupled with numerical optimization technique. The individual and interactive effect of process variables (solid-liquid ratio, pH, extraction time and temperature) on the pectin yield was studied. The experimental data obtained were analyzed by Pareto analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R(2)) value. The optimal extraction condition was found to be 1:17.52 g/ml of solid-liquid ratio, 1.27 of pH, 28.31 min of extraction time and 61.90 °C of extraction temperature respectively. Under the optimal conditions, experimental yield was very close to the predicted values.


Asunto(s)
Lythraceae/química , Pectinas/aislamiento & purificación , Ultrasonido/métodos , Residuos/análisis , Análisis de Varianza , Modelos Teóricos , Análisis de Regresión , Reproducibilidad de los Resultados
10.
Arch Dis Child ; 90(7): 733-6, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15970618

RESUMEN

BACKGROUND: Childhood urinary tract infection (UTI) with or without vesicoureteric reflux (VUR) may predispose to renal scarring. There is no clear consensus in the literature regarding imaging following UTI in infancy. AIMS: To define the role of cystography following a first UTI in children aged under 1 year, when urinary tract ultrasonography (US) is normal. METHODS: Retrospective data collection of 108 children (216 renal units) aged under 1 year at the time of a bacteriologically proven UTI. All had a normal US and underwent both catheter cystogram and DMSA test. Sensitivity, specificity, likelihood ratios positive and negative, and diagnostic odds ratio were calculated for VUR on cystography versus scarring on DMSA. RESULTS: VUR was shown in 25 (11.6%) renal units. Scarring on DMSA was seen in 8 (3.7 %) kidneys. Only 16% of kidneys with VUR had associated scarring; 50% of scarred kidneys were not associated with VUR. The likelihood ratio positive was 4.95 (95% CI 2.22 to 11.05) and the likelihood ratio negative was 0.56 (95% CI 0.28 to 1.11). The diagnostic odds ratio was 8.9, suggesting that cystography provided little additional information. CONCLUSION: Since only 16% of children with VUR had an abnormal kidney, the presence of VUR does not identify a susceptible population with an abnormal kidney on DMSA. In the context of a normal ultrasound examination, cystography contributes little to the management of children under the age of 1 year with a UTI. In this context, a normal DMSA study reinforces the redundancy of cystography.


Asunto(s)
Cicatriz/etiología , Enfermedades Renales/etiología , Infecciones Urinarias/complicaciones , Reflujo Vesicoureteral/complicaciones , Cicatriz/diagnóstico , Cicatriz/diagnóstico por imagen , Femenino , Humanos , Lactante , Recién Nacido , Enfermedades Renales/diagnóstico , Enfermedades Renales/diagnóstico por imagen , Masculino , Radiografía , Cintigrafía , Radiofármacos , Estudios Retrospectivos , Sensibilidad y Especificidad , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/diagnóstico por imagen , Reflujo Vesicoureteral/diagnóstico
11.
Clin Radiol ; 58(12): 964-70, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14654029

RESUMEN

AIM: To determine whether normal postnatal ultrasound, as part of a strict screening protocol for the detection and follow-up of antenatal hydronephrosis, effectively excludes the majority of babies with congenital urinary tract abnormalities that would otherwise present with a urinary tract infection. MATERIALS AND METHODS: We retrospectively reviewed all babies who had postnatal follow-up of antenatally detected hydronephrosis over a 5-year period at our institution, a district general Trust with a specialist paediatric unit. We then studied all babies presenting with urinary tract infection before their first birthday to our institution over the same period. By cross-referencing these two study groups we were able to determine which babies developed a urinary tract infection having been previously discharged after normal postnatal ultrasound. RESULTS: Four hundred and twenty-five babies had postnatal follow-up of antenatal hydronephrosis. Of these, 284 were investigated with ultrasound alone. In the same 5-year period, 230 babies presented with urinary tract infection before their first birthday. Only three of these babies had been previously discharged after normal postnatal ultrasound. The negative predictive value of a normal postnatal ultrasound was therefore 98.9% (281/284) for babies who subsequently presented with a urinary tract infection before their first birthday. CONCLUSION: Careful antenatal and postnatal ultrasound with strict protocols is effective in detecting congenital renal tract abnormalities. Infants discharged after normal postnatal ultrasound are highly unlikely to still have an undetected urinary tract abnormality. We suggest that all babies with antenatal hydronephrosis are started on prophylactic antibiotics at birth, pending further investigation. All babies without features of severe obstruction antenatally should have their postnatal ultrasound delayed for a month. We recommend selective use of micturating cystourethrogram (MCUG), and delaying this investigation until the baby is 3 to 4 months old to allow for spontaneous resolution of vesicoureteric reflux. We do not believe that all babies with antenatal hydronephrosis require MCUG, providing a clear protocol is followed.


Asunto(s)
Hidronefrosis/diagnóstico por imagen , Ultrasonografía Prenatal/normas , Algoritmos , Cuidado del Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Atención Perinatal , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos , Sistema Urinario/anomalías , Reflujo Vesicoureteral/diagnóstico por imagen
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