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1.
Nanomaterials (Basel) ; 13(23)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38063681

RESUMEN

5Ni/MgO and 5Ni/γAl2O3 are pronounced in the line of cheap catalyst systems for the dry reforming of methane. However, the lower reducibility of 5Ni/MgO and the significant coke deposition over 5Ni/γAl2O3 limit their applicability as potential DRM catalysts. The mixing capacity of MgO and Al2O3 may overcome these limitations without increasing the catalyst cost. Herein, a 5Ni/xMg(100 - x)Al (x = 0, 20, 30, 60, 70, and 100 wt. %) catalyst system is prepared, investigated, and characterized with X-ray diffraction, surface area and porosity measurements, H2-temperature programmed reduction, UV-Vis-IR spectroscopy, Raman spectroscopy, thermogravimetry, and transmission electron microscopy. Upon the addition of 20 wt. % MgO into the Al2O3 support, 5Ni/20Mg80Al is expanded and carries both stable Ni sites (derived through the reduction of NiAl2O4) and a variety of CO2-interacting species. CH4 decomposition at Ni sites and the potential oxidation of carbon deposits by CO2-interacting species over 5Ni/20Mg80Al results in a higher 61% H2-yield (against ~55% H2-yield over 5Ni/γAl2O3) with an excellent carbon-resistant property. In the major magnesia support system, the 5Ni/60Mg40Al catalyst carries stable Ni sites derived from MgNiO2 and "strongly interacted NiO-species". The H2-yield over the 5Ni/60Mg40Al catalyst moves to 71%, even against a high coke deposition, indicating fine tuning between the carbon formation and diffusion rates. Ni dispersed over magnesia-alumina with weight ratios of 7/3 and 3/7 exhibit good resistance to coke. Weight ratios of 2/8 and 7/3 contain an adequate amount of reducible and CO2-interactive species responsible for producing over 60% of H2-yield. Weight ratio 6/4 has a proper coke diffusion mechanism in addition to achieving a maximum of 71% H2-yield.

2.
Nanomaterials (Basel) ; 13(21)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37947719

RESUMEN

The catalytic conversion of CH4 and CO2 into H2-rich syngas is known as the dry reforming of methane (DRM). The dissociation of CH4 over active sites, coupled with the oxidation or polymerization of CH4-x (x = 1-4), plays a crucial role in determining in determining the DRM product yield and coke deposition. Herein, a series of bimetallic-supported catalysts are prepared by the dispersion of Ni-M (M = Ce, Co, Fe, and Sr) over 60 wt% MgO-40 wt% Al2O3 (60Mg40Al) support. Catalysts are tested for DRM and characterized with XRD, surface area and porosity, temperature-programmed reduction/desorption, UV-VIS-Raman spectroscopy, and thermogravimetry. 2.5Ni2.5Sr/60Mg40Al and 2.5Ni2.5Fe/60Mg40Al, and 2.5Ni2.5Ce/60Mg40Al and 2.5Ni2.5Co/60Mg40Al have similar CO2 interaction profiles. The 2.5Ni2.5Sr/60Mg40Al catalyst nurtures inert-type coke, whereas 2.5Ni2.5Fe/60Mg40Al accelerates the deposition of huge coke, which results in catalytic inferiority. The higher activity over 2.5Ni2.5Ce/60Mg40Al is due to the instant lattice oxygen-endowing capacity for oxidizing coke. Retaining a high DRM activity (54% H2-yield) up to 24 h even against a huge coke deposition (weight loss 46%) over 2.5Ni2.5Co/60Mg40Al is due to the timely diffusion of coke far from the active sites or the mounting of active sites over the carbon nanotube.

3.
Indian J Ophthalmol ; 71(4): 1478-1482, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37026286

RESUMEN

Purpose: Dry eye is a prevalent disorder of tear film resulting from either decreased tear production or increased tear evaporation. It is becoming a serious issue due to its disturbing symptoms, which become progressively troublesome affecting the work efficiency of patients and increasing financial burden due to lifelong dependency on eye drops. If not detected early, it can lead to sight-threatening complications. This study aims to explore serum vitamin D3 deficiency as a causative factor of dry eye. Methods: The study was conducted in the outpatient department of a tertiary care hospital in India, for a period of two years from September 2018 to September 2020. About 40 patients who had dry eye and 20 controls were enrolled in this study. They were given an Ocular Surface Disease Index (OSDI) questionnaire, examined for signs of dry eye on slit lamp with Schirmer's test and tear film break-up time. All 60 participants were subjected to serum vitamin D3 level laboratory test and its deficiency prevalence was correlated with dry eye and its severity. Results: Serum vitamin D3 deficiency was found to be more prevalent in patients with dry eye. There was no gender predilection or change in prevalence with increasing age. Vitamin D3 level was negatively correlated with OSDI and positively with Schirmer's test 1 and 2 and tear film break-up time (TBUT) scores. Conclusion: The prevalence of vitamin D3 deficiency was not consistently found to be associated with the increasing severity of dry eye.


Asunto(s)
Síndromes de Ojo Seco , Deficiencia de Vitamina D , Humanos , Colecalciferol , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/epidemiología , Síndromes de Ojo Seco/etiología , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/diagnóstico , Deficiencia de Vitamina D/epidemiología , Soluciones Oftálmicas , Lágrimas
4.
Glob J Qual Saf Healthc ; 6(3): 77-80, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38405329

RESUMEN

Introduction: Every organization needs well-trained employees to perform job activities effectively and efficiently. Training and development is a continuous process that helps to develop skills, knowledge, and abilities in its workers, which leads to better performance of employees. This study aims to assess the effectiveness of an induction training program for hospital employees as well as the impact on employee knowledge and performance in the clinical field according quality indicator benchmarks. Methods: A sample of individuals (N = 775) who were newly hired, promoted, or re-categorized at our institution in 2021 were included in the program. The effectiveness of the induction training program was assessed with a pre- and post-test and feedback form. Topics covered in the training program will help employees know about the institute and increase knowledge and skills. Results: The average pre-test score was 60%, which increased to 84% after the training (p = 0.0001). There was a significantly positive relationship between the quality indicators and the clinical audit results (p = 0.006). Conclusion: The induction training program effectively improved the employees' knowledge regarding their rights and responsibilities as well as clinical knowledge (i.e., Infection control and prevention, quality, disaster management, biomedical waste management, and facility safety).

5.
Zootaxa ; 5020(3): 401-433, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34810993

RESUMEN

A new species of natricine snake of the genus Rhabdophis is described from Northeast India. Morphologically the new species is similar to Rhabdophis himalayanus but it can be distinguished from it by lacking a nuchal groove and nuchal glands, being relatively smaller, and having a distinct neck, ventral, and subcaudal coloration. In overall coloration it resembles R. chrysargos, from which it is distinguished by several aspects of its morphology and genetic differences. The discovery of Rhabdophis bindi sp. nov. reveals that forested regions in the northeastern part of India needs further biological exploration.


Asunto(s)
Colubridae , Animales , Bosques
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