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1.
Chemosphere ; 359: 142354, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38759812

RESUMEN

Degradation of ibuprofen, one of the most consumed drugs globally, by a mixed bacterial consortium was investigated. A contaminated hospital soil was used to enrich a bacterial consortium possessing the ability to degrade 4 mg/L ibuprofen in 6 days, fed on 6 mM acetate as a supplementary carbon source. Maximum ibuprofen degradation achieved was 99.51%, and for optimum ibuprofen degradation modelled statistically, the initial ibuprofen concentration, and temperature were determined to be 0.515 mg/L and 35 °C, respectively. The bacterial community analyses demonstrated an enrichment of Pseudomonas, Achromobacter, Bacillus, and Enterococcus in the presence of ibuprofen, suggesting their probable association with the biodegradation process. The biodegradation pathway developed using open-source metabolite predictors, GLORYx and BioTransformer suggested multiple degradation routes. Hydroxylation and oxidation were found to be the major mechanisms in ibuprofen degradation. Mono-hydroxylated metabolites were identified as well as predicted by the bioinformatics-based packages. Oxidation, dehydrogenation, super-hydroxylation, and hydrolysis were some other identified mechanisms.


Asunto(s)
Biodegradación Ambiental , Ibuprofeno , Consorcios Microbianos , Ibuprofeno/metabolismo , Redes y Vías Metabólicas , Bacterias/metabolismo , Microbiología del Suelo , Oxidación-Reducción , Hidroxilación , Pseudomonas/metabolismo , Achromobacter/metabolismo , Contaminantes del Suelo/metabolismo , Bacillus/metabolismo
2.
J Ayurveda Integr Med ; 14(2): 100690, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36822148

RESUMEN

In Ayurveda, 'Lauha' (Iron) Bhasma is primarily used to cure diseases related to iron deficiency in humans. It is produced from purified raw metallic iron using a combination of multi-step traditional preparation processes described in the Ayurveda literature. Here, we present the results of structural investigation performed on the medicinal grade 'Lauha' Bhasma using various X-ray based techniques. Our results indicate that after several rounds of heating and cooling in specific conditions following the Ayurvedic preparation procedure, metallic iron eventually converts to a natural iron-oxide mineral belonging to the magnetite group. Scanning electron microscopy (SEM) and X-ray standing wave assisted fluorescence measurements carried out on powdered Bhasma specimen reveal that the magnetite micro-particles in the Bhasma specimen are usually present in the form of agglomerates of nano-particles. We anticipate that the Ayurvedic Lauha Bhasma has great potential for noninvasive localized target killing of cancer cells, particularly in sensitive parts of the human body such as the brain, spinal cord, and lungs, via necrosis by application of an alternating external magnetic field or photo electron generation through X-rays.

3.
Water Environ Res ; 94(7): e10759, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35796043

RESUMEN

The pollutants released from pharmaceutical, steel, paper, and battery industries into water cause stress on the natural ecosystems, may mix with soil and water, enter into human food chain, and hence cause irreparable damage to the biotic system. Hence, the appropriate monitoring of water along with determination of heavy metals is very important for human beings. In present paper, total reflection X-ray fluorescence (TXRF) spectrometry technique is employed to determine the level of different contaminants in the water samples gathered from the various sites of an identified industrial area. Experimentation is carried out at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore-India by using TXRF, which is one the advance techniques of element determination up to ppb levels. The elemental concentration of Cl, K, Ca, Fe, Cu, Zn, Ga, Br, Sr, As, Pb, and Ni is quantified and compared with the limits established by the WHO (World Health Organization) and BIS (Bureau of Indian Standard) guidelines regarding drinking water use. The levels of the Pb, Fe, As, Ni, Cr, Co, and Mn exceeded the values suggested by WHO and BIS at some locations/sites. To better understand the situation, water quality parameters such as Water Quality Index (WQI), Heavy metal Pollution Index (HPI), Contamination Index (CI), Metal Enrichment Index (MEI), and Heavy Metal Evaluation Index (HEI) have also been assessed for all the sites close to industrial hub. Among all sites except at A3 and A6, WQI is found to be much greater than WHO and BIS established limit. Level of arsenic in the water at A1 location was found 73 ppb. However, lead metal in water was found to be very high at all the six studied locations, and at A1 location, it is found extremely high 2613 ppb. Therefore, water at A1 and A2 sites is found to be unfit for drinking. PRACTITIONER POINTS: Total reflection X-ray fluorescence (TXRF) spectrometry technique is employed to determine the level of different contaminants in the water samples The elemental concentration of Cl, K, Ca, Fe, Cu, Zn, Ga, Br, Sr, As, Pb, and Ni is quantified and compared with the limits prescribed by the WHO Water Quality Index (WQI), Heavy metal Pollution Index (HPI), Contamination Index (CI), Metal Enrichment Index (MEI), and Heavy Metal Enrichment Index (MEI) have also been assessed for all the sites Water at some sites is found unfit for drinking purpose. Based on the observations, some remedial measures are suggested to reduce the level of water contaminants up to desired levels.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente/métodos , Humanos , Plomo , Metales Pesados/análisis , Sincrotrones , Contaminantes Químicos del Agua/análisis , Calidad del Agua , Rayos X
4.
Biol Trace Elem Res ; 200(4): 1485-1494, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34076844

RESUMEN

A total of 158 serum samples of newly diagnosed type 2 diabetes patients and control subjects were analyzed using Synchrotron Radiation X-ray Fluorescence (SRXRF) technique. The microprobe XRF beam line-16 of Indus-2 synchrotron radiation facility at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore, India, was used to identify and quantify the elements K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, and Pb. A significant decrease in the mean concentrations of K, Ca, Ti, Cr, Mn, Ni, Zn, and As and an increase in the concentrations of V, Fe, Co, Cu, Se, and Pb were observed in the serum samples of the patient group when compared to the control group. It is hypothesized that the observed alterations in the elemental concentrations might have led to ineffective uptake of insulin and have interfered with glucose homeostasis by either directly or indirectly causing oxidative stress.


Asunto(s)
Diabetes Mellitus Tipo 2 , Oligoelementos , Fluorescencia , Humanos , India , Sincrotrones , Oligoelementos/análisis , Rayos X
5.
Appl Radiat Isot ; 128: 210-215, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28735114

RESUMEN

Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique.

6.
Anal Chem ; 89(1): 871-876, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27936602

RESUMEN

Total reflection X-ray fluorescence (TXRF)-based X-ray absorption near-edge spectroscopy has been used to determine the oxidation state of uranium in mixed-valent U3O8 and U3O7 uranium oxides. The TXRF spectra of the compounds were measured using variable X-ray energies in the vicinity of the U L3 edge in the TXRF excitation mode at the microfocus beamline of the Indus-2 synchrotron facility. The TXRF-based X-ray absorption near-edge spectroscopy (TXRF-XANES) spectra were deduced from the emission spectra measured using the energies below and above the U L3 edge in the XANES region. The data processing using TXRF-XANES spectra of U(IV), U(V), and U(VI) standard compounds revealed that U present in U3O8 is a mixture of U(V) and U(VI), whereas U in U3O7 is mixture of U(IV) and U(VI). The results obtained in this study are similar to that reported in literature using the U M edge. The present study has demonstrated the possibility of application of TXRF for the oxidation state determination and elemental speciation of radioactive substances in a nondestructive manner with very small amount of sample requirement.

8.
Rev Sci Instrum ; 86(5): 055102, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26026553

RESUMEN

A new multipurpose x-ray reflectometer station has been developed and augmented at the microfocus beamline (BL-16) of Indus-2 synchrotron radiation source to facilitate synchronous measurements of specular x-ray reflectivity and grazing incidence x-ray fluorescence emission from thin layered structures. The design and various salient features of the x-ray reflectometer are discussed. The performance of the reflectometer has been evaluated by analyzing several thin layered structures having different surface interface properties. The results reveal in-depth information for precise determination of surface and interface properties of thin layered materials demonstrating the immense potential of the combined measurements of x-ray reflectivity and grazing incidence fluorescence on a single reflectometer.

9.
J Synchrotron Radiat ; 20(Pt 2): 386-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23412498

RESUMEN

A microfocus X-ray fluorescence spectroscopy beamline (BL-16) at the Indian synchrotron radiation facility Indus-2 has been constructed with an experimental emphasis on environmental, archaeological, biomedical and material science applications involving heavy metal speciation and their localization. The beamline offers a combination of different analytical probes, e.g. X-ray fluorescence mapping, X-ray microspectroscopy and total-external-reflection fluorescence characterization. The beamline is installed on a bending-magnet source with a working X-ray energy range of 4-20 keV, enabling it to excite K-edges of all elements from S to Nb and L-edges from Ag to U. The optics of the beamline comprises of a double-crystal monochromator with Si(111) symmetric and asymmetric crystals and a pair of Kirkpatrick-Baez focusing mirrors. This paper describes the performance of the beamline and its capabilities with examples of measured results.


Asunto(s)
Sincrotrones/instrumentación , Cristalografía por Rayos X/métodos , Diseño de Equipo , India , Solanum lycopersicum/química , Hojas de la Planta/química , Espectrometría por Rayos X/métodos
10.
J Synchrotron Radiat ; 17(2): 237-42, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20157277

RESUMEN

In this paper the first practical application of kinoform lenses for the X-ray reflectivity characterization of thin layered materials is demonstrated. The focused X-ray beam generated from a kinoform lens, a line of nominal size approximately 50 microm x 2 microm, provides a unique possibility to measure the X-ray reflectivities of thin layered materials in sample scanning mode. Moreover, the small footprint of the X-ray beam, generated on the sample surface at grazing incidence angles, enables one to measure the absolute X-ray reflectivities. This approach has been tested by analyzing a few thin multilayer structures. The advantages achieved over the conventional X-ray reflectivity technique are discussed and demonstrated by measurements.

11.
J Phys Condens Matter ; 22(17): 175003, 2010 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-21393661

RESUMEN

By measuring the intensities of the x-ray standing wave induced elastic and inelastic x-ray scattering from thin multilayer structures, we show that structural characterizations of the high and low z (atomic number) material layers can be performed independently. The method has been tested by analyzing the structural properties of an Nb/C/Nb trilayer and an Mo/Si periodic multilayer structure. The results of the x-ray scattering measurements have been compared with those obtained using x-ray reflectivity and conventional x-ray standing wave fluorescence techniques. It has been demonstrated that the present approach is especially suitable for studying multilayer structures comprising low atomic number layers, as it eliminates the requirement of a fluorescence signal, which is very weak in the case of low z materials.

12.
Environ Monit Assess ; 162(1-4): 225-35, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19234750

RESUMEN

We present diurnal variation of ambient ammonia (NH(3)) in relation with other trace gases (O(3), CO, NO, NO(2), and SO(2)) and meteorological parameters at an urban site of Delhi during winter period. For the first time, ambient ammonia (NH(3)) was monitored very precisely and continuously using ammonia analyzer, which operates on chemiluminescence method. NH(3) estimation efficiency of the chemiluminescence method (>90%) is much higher than the conventional chemical trapping method (reproducibility 4.5%). Ambient NH(3) concentration reaches its maxima (46.17 ppb) at night and minimum during midday. Result reveals that the ambient ammonia (NH(3)) concentration is positively correlated with ambient NO (r(2) = 0.79) and NO(2) (r (2) = 0.91) mixing ratio and negatively correlated with ambient temperature (r(2) = - 0.32). Wind direction and wind speed indicates that the nearby (approximately 500 m NW) agricultural fields may be major source of ambient NH(3) at the observational site.


Asunto(s)
Amoníaco/análisis , Gases/química , Luminiscencia , Espectrofotometría Ultravioleta
13.
J Synchrotron Radiat ; 16(Pt 3): 325-9, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19395794

RESUMEN

The unprecedented brilliance achieved by third-generation synchrotron sources and the availability of improved optics have opened up new opportunities for the study of materials at the micrometre and nanometre scale. Focusing the synchrotron radiation to smaller and smaller beams is having a huge impact on a wide research area at synchrotrons. The key to the exploitation of the improved sources is the development of novel optics that deliver narrow beams without loss of brilliance and coherence. Several types of synchrotron focusing optics are successfully fabricated using advanced miniaturization techniques. Kinoform refractive lenses are being developed for hard X-ray beamlines, and the first test results at Diamond are discussed in this paper.


Asunto(s)
Diamante , Germanio , Lentes , Refractometría/instrumentación , Sincrotrones/instrumentación , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
J Nanosci Nanotechnol ; 8(4): 1757-61, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18572575

RESUMEN

Polyaniline (PANI)-ZnO nanocomposite thin film has been successfully fabricated on glass substrates by using vacuum deposition technique. The as-grown PANI-ZnO nanocomposite thin films have been characterized using X-ray diffraction, Scanning Electron Microscopy, Atomic Force Microscopy, UV-visible spectrophotometer and Fourier Transform Infrared (FTIR) spectroscopy, respectively. X-ray diffraction of as-grown film shows the reflection of ZnO nanoparticles along with a broad peak of PANI. The surface morphology of nanocomposite films has been investigated using scanning electron microscopy and atomic force microscopy. The hypsochromic shift of the UV absorption band corresponding to pi-pi* transition in polymeric chain of PANI and a band at 504 cm(-1) due to ZnO nanoparticles has been observed in the FTIR spectra. The hydrogen bonding between the imine group of PANI and ZnO nanoparticle has been confirmed from the presence of the absorbance band at 1151 cm(-1) in the FTIR spectra of the nanocomposite thin films.


Asunto(s)
Compuestos de Anilina/química , Cristalización/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Óxido de Zinc/química , Sustancias Macromoleculares/química , Ensayo de Materiales , Membranas Artificiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
15.
Appl Opt ; 46(8): 1205-10, 2007 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-17318240

RESUMEN

A study of silver, chromium, stainless-steel, and indium thin films prepared by subnanosecond laser deposition in vacuum is reported. We compare the laser ablation in vacuum at the weak- and tight-focusing conditions of a Ti:sapphire laser beam and analyze the nanoparticles synthesized in the latter case using absorption spectroscopy, x-ray fluorescence, atomic force microscopy, and scanning electron microscopy. Our results show that the nanoparticle formation can be accomplished using long laser pulses under tight-focusing conditions.

16.
Anal Sci ; 21(7): 757-62, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16038490

RESUMEN

Incident primary beam divergence is a source of systematic error in X-ray standing wave (XSW) characterization of single and multilayer thin films. Primary beam divergence significantly alters the XSW profile of a layered material and can lead to large errors when used with higher excitation energies. The present study suggests that when one uses Mo-Kalpha excitation, the primary beam divergence should be in range of 0.005(0). On the other hand, in the case of Cu-Kalpha excitation, primary beam divergence can be relaxed up to 0.01(0).

17.
Anal Sci ; 21(2): 143-7, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15732474

RESUMEN

The influence of analyte mass concentration on determination of detection limits in X-ray fluorescence spectrometry has been investigated experimentally. Both the total reflection X-ray fluorescence (TXRF) and the conventional energy-dispersive X-ray fluorescence techniques have been used to derive the dependence of analyte mass concentration on the values of detection limits. Results obtained indicate that values of detection limits are optimum, or in other words, they are closer to the true detection limit of the technique, when analyte concentrations are in the range of 10 times of the detection limit.

18.
Water Sci Technol ; 50(6): 235-40, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15537012

RESUMEN

Reetha (Sapindus trifoliata) seed extract and Chitosan were used as additives in the sludge bed of a UASB reactor treating low strength wastewater to enhance granulation. Five parallel laboratory scale UASB reactors were operated for 250 days with synthetic wastewater feed containing COD in the range of 600-800 mg/L. The reactors were seeded with spent sludge from a full-scale 5MLD UASB treatment plant at Jajmau, Kanpur, India. The seed sludge contained little or no granules. Different additives in the five reactors were as follows: control with no additive, cationic part of Reetha extract as additive, anionic part of Reetha extract as additive, bulk Reetha extract as additive and Chitosan as additive. The granulation rapidly increased in all the reactors beyond the 90th day of operation. The mean granule sizes as well as the fraction of granular sludge (particle size > or = 100 microm) were more in the presence of some of the additives compared to the control reactor. Chitosan significantly enhanced granulation followed by the cationic and anionic fractions of the Reetha extract. The bulk Reetha extract did not show enhancement of granulation. The ESEM/EDAX results showed that the bigger granules (3-4 mm) had porous structure and appeared as conglomerates of smaller granules.


Asunto(s)
Reactores Biológicos , Quitosano/química , Extractos Vegetales/química , Polímeros/química , Eliminación de Residuos Líquidos/métodos , India , Tamaño de la Partícula , Porosidad , Semillas/química , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología
19.
Neurol India ; 50(4): 424-9, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12577089

RESUMEN

Primary central nervous system lymphomas (PCNSL) constitutes only 1.0 to 1.5% of all brain tumors. Their incidence has gone up over tenfold in the last 25 years. Though, there has been an association of PCNSL with acquired immune deficiency syndrome (AIDS), yet the increased incidence of PCNSL appears to be real and unrelated to AIDS and organ transplantation. This increased incidence could be because of improvement in diagnostic technology and practice. The outcome remains gloomy despite surgical resection, radiotherapy and intensive adjuvant chemotherapy regimens, as majority of the patients succumb to the disease, with only 30-40% survival in patients under 70 years of age.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Linfoma/diagnóstico , Adolescente , Adulto , Neoplasias Encefálicas/clasificación , Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/terapia , Femenino , Humanos , India/epidemiología , Linfoma/clasificación , Linfoma/epidemiología , Linfoma/terapia , Masculino , Persona de Mediana Edad
20.
Coll Antropol ; 26(2): 501-7, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12528273

RESUMEN

A cross-sectional study of adolescent growth was undertaken among the Brahmin girls residing in rural and urban areas of Sagar districts, Madhya Pradesh to evaluate the urban-rural differences. Six anthropometric measurements, such as weight, stature, sitting height, head circumference, upper arm circumference and chest girth are taken into consideration. Though the urban girls show consistently higher values of weight, stature, sitting height and chest girth than the rural girls, but in case of head circumference and upper arm circumference they show consistently lower values. The maximum increment occurs between the ages 13 and 14 years in all the six measurements in both rural and urban girls.


Asunto(s)
Etnicidad , Crecimiento , Población Rural , Clase Social , Población Urbana , Adolescente , Antropometría , Estudios Transversales , Femenino , Humanos , India , Salud Rural , Factores Socioeconómicos , Salud Urbana
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