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1.
J Nanosci Nanotechnol ; 20(6): 3724-3733, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748070

RESUMO

Electrochromic phenomenon is an emerging technology for renewable energy applications. Several material oxides used for the electrochromic application, the tungsten oxide (WO3) has shown good coloration efficiency (CE). Present manuscript, we are reporting the results of the coloration efficiency of DC magnetron sputtered WO3 films for electrochromic applications (thicknesses 190 nm to 700 nm) with sputter gas neon at 300 K. Hydrogen and Lithium ions have been intercalated into WO3 lattice for coloration. The CE value is increasing with increase of thickness of WO3 thin films; CE for 700 nm thick films are: 87 cm²/C and 137 cm²/C for H+ and Li+ respectively. The coloration efficiency (CE) observed to be increasing with wavelength. The maximum efficiency of the hydrogen intercalated neon sputtered films achieved at 860 nm wavelength is about 129.9 cm²/C and for the lithium intercalatedWO3 films the maximum efficiency achieved at 780 nm with 238.5 cm²/C. These neon sputtered WO3 thin films show good stability of coloration efficiency even after 500 cycles of coloring and bleaching cycles. The work function of the colored and transparent states of WO3 thin films are 4.513 eV and 4.755 eV respectively. Finally we have fabricated the electrochromic device (ECD) prepared with nafion thin film as an ion conducting layer and the ECD has shown a maximum coloration efficiency (CE) of 112.1 cm²/C.

2.
Phys Chem Chem Phys ; 16(45): 24790-9, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25317786

RESUMO

The present work describes in detail the photocatalytic properties of controlled titanium doped indium tin oxide (Ti/TiO2-ITO) composite thin films prepared by DC magnetron sputtering and their applicability to developing a bio-medical lung assistive device. The catalytic films of various thicknesses (namely, C1, C2, C3 and C4) were characterized using surface imaging (SEM), X-ray analyses (XRD and EDX), and Raman studies. The optical band gaps of the prepared films are ∼3.72-3.77 eV. Photocatalytic efficiencies of the film catalysts were investigated with the aid of a model organic molecule (Rhodamine B dye). The overall photodegradation capacity of the films was found to be slow kinetically, and the catalyst C1 was identified as having a better degradation efficiency (RhB 5 ppm, at pH 6.5) over 5 h under irradiation at 254 nm. The distinctive features of these composite films lie in their oxygen accumulation capacity and unique electron-hole pair separation ability. Investigations on oxygen species revealed the formation of superoxide radicals in aqueous systems (pH 6.5). The prepared films have TiO2 in the anatase phase in the surfaces, and possess the desired photocatalytic efficiency, compatibility to the heme system (are not involved in harmful hydroxyl radical production), and appreciable reusability. Especially, the thin films have a significant ability for mobilization of oxygen rapidly and continuously in aqueous medium under the irradiation conditions. Hence, these films may be a suitable choice for the photo-aided lung assistive design under development.


Assuntos
Equipamentos e Provisões , Oxigênio/química , Fotólise , Compostos de Estanho/química , Titânio/química , Catálise , Corantes/química , Sequestradores de Radicais Livres/química , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Ópticos , Espécies Reativas de Oxigênio/química , Propriedades de Superfície
3.
J Nanosci Nanotechnol ; 9(9): 5208-13, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19928202

RESUMO

InN films are grown on silicon and glass substrates by radio frequency (rf) activated reactive evaporation. High purity indium (99.99) is evaporated by resistive heating in the presence of nitrogen plasma. X-ray diffraction shows that the film deposited at low rf plasma powers (< or =100 W) are indium rich and further increase in the rf power formation of InN take place. The average crystallite size was found varying from 8 nm to 20 nm as the power increases from 200 to 400 W. The diffraction pattern shows the polycrystalline nature of InN films. The band gap obtained from the transmission spectra show an increase in the band gap with the increase in rf power which can be attributed to variation of nitrogen: indium stoichiometry. The Raman spectra shows wurtzite nature of the film and the photoluminescence measurements show a weak peak around 1.81 eV for the film grown at 400 W. Plasma diagnostics has been carried out in order to understand the role of active species in the process. The large shift in the band gap is attributed to Moss-Burstein shift and presence of residual oxygen in the film.

4.
J Agric Food Chem ; 50(4): 933-7, 2002 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-11829670

RESUMO

High-titer rabbit polyclonal antibodies to aflatoxin M(1) (AFM1) were produced by utilizing AFM1-bovine serum albumin (BSA) conjugate as an immunogen. An indirect competitive enzyme-linked immunosorbent assay was standardized for estimating AFM1 in milk and milk products. To avoid the influence of interfering substances present in the milk samples, it was necessary to prepare AFM1 standards in methanol extracts of certified reference material (CRM) not containing detectable AFM1 (< 0.05 ng/g). The reliability of the procedure was assessed by using CRM with AFM1 concentrations of < 0.5 and 0.76 ng/g. Also, assays of milk samples mixed with AFM1 ranging in concentration between 0.5 and 50 ng/L gave recoveries of > 93%. The relative cross-reactivity with aflatoxins (AF) and ochratoxin A, assessed as the amount of AFM1 necessary to cause 50% inhibition of binding, was 5% for AFB1 and much less for AFB2, AFG1, and AFG2; there was no reaction with ochratoxin A. AFM1 contamination was measured in retail milk and milk products collected from rural and periurban areas in Andhra Pradesh, India. Of 280 milk samples tested, 146 were found to contain < 0.5 ng/mL of AFM1; in 80 samples it varied from 0.6 to 15 ng/mL, in 42 samples from 16 to 30 ng/mL, and in 12 samples from 31 to 48 ng/mL. Most of the milk samples that contained high AFM1 concentrations were obtained from periurban locations. The results revealed a significant exposure of humans to AFM1 levels in India and thus highlight the need for awareness of risk among milk producers and consumers.


Assuntos
Aflatoxina M1/análise , Laticínios/análise , Ensaio de Imunoadsorção Enzimática/métodos , Leite/química , Animais , Especificidade de Anticorpos , Ligação Competitiva , Doces/análise , Contaminação de Alimentos , Humanos , Índia , Lactente , Alimentos Infantis/análise , Ocratoxinas/análise
5.
Int J Cardiol ; 57(1): 31-5, 1996 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-8960940

RESUMO

Eight children, age between 4.5 and 19 years were treated with moricizine for supraventricular tachycardia during the last 3 years. The tachycardia was documented by surface electrocardiogram (ECG), and/or by ambulatory ECG in all the children and the mechanism of tachycardia was determined by previously published surface ECG and electrophysiologic criteria in all but one child. Of the eight children, three had atrial ectopic tachycardia, three had automatic junctional ectopic tachycardia, one had atrioventricular (AV) nodal reentry tachycardia and one had atrial reentry. All the children except one had failed trial of two or more antiarrhythmic drugs prior to moricizine therapy. The duration of moricizine therapy ranged from 4 days to 25 months. In three of the eight children (patients 3, 5 and 7), who presented with AV nodal reentrant tachycardia, automatic junctional ectopic tachycardia and atrial ectopic tachycardia, respectively, moricizine therapy was effective in restoring sinus rhythm and controlling the clinical tachycardia. Only one child (patient 1) developed proarrhythmia, an episode of fast, narrow-QRS supraventricular tachycardia lasting for 30 s, on the third day of therapy. This was subsequently confirmed by electrophysiologic study to be AV nodal reentrant tachycardia. The other side effects noted were non-cardiac, not dose-dependant and did not require dis-continuation of therapy. Based on our small series and those of others, moricizine, a newer class I anti-arrhythmic agent, has a limited but useful role in the management of recalcitrant type of supraventricular tachycardia, such as ectopic atrial and junctional tachycardia in children.


Assuntos
Antiarrítmicos/uso terapêutico , Moricizina/uso terapêutico , Taquicardia Supraventricular/tratamento farmacológico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Taquicardia por Reentrada no Nó Atrioventricular/tratamento farmacológico , Resultado do Tratamento
6.
Pediatr Cardiol ; 17(4): 231-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8662045

RESUMO

Propranolol, a first-generation nonselective beta-adrenoceptor blocking agent, is commonly used to treat pediatric arrhythmias. Atenolol, relatively long-acting, cardioselective beta-adrenoceptor blocking agent, has been successfully used in adults with supraventricular tachycardia (SVT). There is only one report on the use of atenolol in children with SVT; and our report is on the first long-term prospective study to evaluate the use of atenolol in children. A group of 22 children < 18 years of age with clinical SVT were enrolled in the study. The tachycardia was documented on electrocardiograms in each case and was confirmed by electrophysiologic studies in some. Once-a-day oral atenolol was started as a monotherapy. Of the 22 children with various types of SVT, 13 (59%) were well controlled on long-term oral atenolol therapy. The effective dose of atenolol ranged between 0.3 and 1.3 mg/kg/day (median effective dose 0.7 mg/kg/day). Five children had some adverse effects. However, none in the successful group of 13 patients required drug discontinuation because of such effects. Once-a-day oral atenolol as a monotherapy is effective and relatively safe for long-term management of SVT during childhood. It is an attractive alternative beta-adrenoceptor blocking agent for the management of pediatric arrhythmias.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Atenolol/uso terapêutico , Taquicardia Supraventricular/tratamento farmacológico , Adolescente , Antagonistas Adrenérgicos beta/administração & dosagem , Atenolol/administração & dosagem , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento
11.
Mycoses ; 36(5-6): 201-2, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8264717

RESUMO

Thermomucor indicae-seudaticae Subrahmanyam et al. was found for the first time growing as commensal associated with pityriasis versicolor on the skin of a 25-year-old man living in a small village near Pune, Maharastra, India. The clinical observations and morphological characters are presented. A small percentage of zygospores was found to germinate in situ but further stages of development could not be found.


Assuntos
Mucorales/isolamento & purificação , Pele/microbiologia , Tinha Versicolor/microbiologia , Adulto , Humanos , Masculino , Mucorales/citologia , Mucorales/crescimento & desenvolvimento
19.
Mykosen ; 26(9): 478-80, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6646169
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