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1.
Nanomaterials (Basel) ; 13(16)2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37630914

RESUMO

Designing efficient electrocatalytic systems through facile synthesis remains a formidable task. To address this issue, this paper presents the design of a combination material comprising two transition metal oxides (copper oxide and manganese oxide (CuO/MnO2)), synthesized using a conventional microwave technique to efficiently engage as an active oxygen evolution reaction (OER) catalyst. The structural and morphological properties of the composite were confirmed by the aid of X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectrometry (EDS). FESEM clearly indicated well-aligned interlacing of CuO with MnO2. The OER performance was carried out in 1 M KOH. The assembled CuO/MnO2 delivered a benchmark current density (j = 10 mA cm-2) at a minimal overpotential (η = 294 mV), while pristine CuO required a high η (316 mV). Additionally, the CuO/MnO2 electrocatalyst exhibited stability for more than 15 h. These enhanced electrochemical performances were attributed to the large volume and expanded diameter of the pores, which offer ample surface area for catalytic reactions to boost OER. Furthermore, the rate kinetics of the OER are favored in composite due to low Tafel slope (77 mV/dec) compared to CuO (80 mV/dec).

2.
Chemosphere ; 289: 133197, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890623

RESUMO

The invention of cost-effective, clean, and eco-friendly energy storage technology has been capturing a lot of worldwide interest. Herein, biogenically synthesized TiO2 nanoparticles (NPs) were ultrasonically coupled with biomass-derived activated carbon (BAC) to obtain composite (denoted as TiO2@BAC). With the inspiration of nature, Mentha Aquatica leaves extract was employed for biogenic preparation of TiO2 NPs, and residual solid waste (SW) after extract was subsequently utilized for BAC. It is noteworthy that, this unique intensive method does not require any harmful or toxic chemicals and solvents, and no secondary waste is generated. TEM analysis of TiO2@BAC revealed spherical morphology of TiO2 NPs (average size âˆ¼ 18 nm) that were accumulated on nanosheets. Raman, XRD, and XPS manifested the successful construction of TiO2@BAC. The electrochemical performance of the as-synthesized BAC, TiO2 NPs, and TiO2@BAC electrodes was tested towards supercapacitor applications. Notably, the TiO2@BAC electrode exhibited capacitance of 149 F/g at a current density of 1 A/g, which is approximately twice than that of the bare TiO2 electrode (76 F/g) along with excellent capacitance restoration of ∼99%. The TiO2@BAC electrode further revealed outstanding cyclic stability, exhibiting capacitance retention of ∼90% (at 5 A/g) after 10,000 charge/discharge cycles. Furthermore, the TiO2@BAC electrode delivered optimal specific energy density (6.96 Wh/kg) and large power density (2.07 kW/kg at 10 A/g). Moreover, the TiO2@BAC delivers an excellent restoration and retention performances of ∼100 and ∼95% (after 10,000 cycles) at 1 A/g with ∼98% coulombic efficiency in symmetric configuration (maximum cell voltage of 1.2 V).


Assuntos
Mentha , Capacitância Elétrica , Eletrodos , Titânio
3.
Artigo em Inglês | MEDLINE | ID: mdl-23137197

RESUMO

INTRODUCTION: Cricket is the most popular sport in India, and is gaining in importance in all south-east Asian countries. The purpose of this study was to prospectively investigate the incidence, nature, and site of acute upper limb injuries sustained by professional cricketers of north India over a period of one year. MATERIAL & METHODS: 95 cricket players (mean age 18.9 years) were prospectively evaluated for nature and incidence of upper limb injuries from 1st November 2008 to 31st October 2009. For the purpose of comparison the calculated injury incidence included injuries sustained during match as well as practice. Injuries were also grouped according to the type of cricket activities such as batting or fielding. RESULTS: Out of 95 players evaluated, 24 were bowlers, 19 were batsmen, 8 were wicket keepers and the other 44 cricketers declared themselves as all rounders. There were a total of 16 upper limb injuries in 16 (16.8%) players. The majority of injuries (10/16) occurred while fielding. Out of 16 injuries, 11 were seen in hand, 3 were observed in elbow, while 2 patients suffered from shoulder problem. Twelve were acute injuries while 4 were classified as repetitive stress injuries (RSI). CONCLUSION: The incidence of upper limb injuries in cricketers at the professional and semi-professional level is significant, causing them to miss matches or practice for a significant number of days. This is the first study of Indian cricketers which documents the high incidence of upper limb injuries. The study highlights the importance of injury surveillance for Indian cricket. It is a concern which needs to be addressed by the players, coaches, teachers, administrators and medical personnel involved with cricket.

4.
J Surg Tech Case Rep ; 4(1): 15-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23066456

RESUMO

BACKGROUND: Distal interlocking screw insertion in intramedullary nailing of long-bone fracture is a challenging task for orthopedic surgeons. It is difficult particularly when the surgeon is in his learning stage or when image intensifier is not available. We describe a radiation-free technique of distal interlocking screw insertion which is easy and practicable. MATERIALS AND METHODS: In this technique, a same length nail is placed over the skin (outer nail) and through its distal-most screw hole, a 3.2 mm drill bit is inserted to drill the distal locking screw hole of the intramedullary nail (inner nail). With a small skin incision over the distal screw holes, the distal-most screw hole is identified; the bone window overlying the screw hole is widened with an awl and a locking bolt is inserted with a washer under direct visualization. The other distal interlocking screw is simply drilled by matching the other three holes of the outer and inner nails. We have operated 86 patients (39 femoral shaft fracture and 47 tibial shaft fracture) in 1 year where this technique was used. There were 41 open fracture and 45 closed fracture. RESULTS: Within 6 months of follow-up, bony union was achieved in 36 of 39 femur fractures and 45 of 47 tibial fractures. No unwanted complications were observed during the postoperative period and in follow-up. CONCLUSION: This method of radiation-free distal interlocking screw insertion is simple and can be used in third world country where image intensifier facility is not available. However, surgeons are encouraged to use image intensifier facility where the facility is available.

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