National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Enantioselective synthesis. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

Use of rubber dam and irrigant selection in UK general dental practice.

Abstract: Aim To evaluate factors which influence rubber dam use and irrigant selection in UK National Health Service (NHS) endodontics. Methodology A postal survey was conducted amongst two age cohorts of dentists, representing all of the 1970–73 (older) and 1990–93 (younger) graduates of two northern English dental schools (n = 643). Key and supplementary questions were posed on levels of rubber dam use, irrigant selection, and factors influencing practice in NHS endodontics. After manual checking, validated (dual) entry of responses was made to a flat ASCII data file before analysis with SPSS software. The threshold for statistical significance was set at the 95% probability level. Results Eighty-five per cent of the valid sample responded to the questionnaire. Regardless of age and qualifying school, less than one-fifth of dentists always or frequently used rubber dam, whilst 60% never used it. Qualifying school had a significant influence on rubber dam use, whilst age had a variable influence. Major disincentives to the use of rubber dam included the perception that patients do not like it, that the NHS fee was inadequate to justify its use, that it took too long to apply, and that dentists had received inadequate training. Frequent users of rubber dam were significantly less likely to cite these disincentives than nonusers. Overall, local anaesthetic solution was the most common endodontic irrigant. Irrigant choice was strongly linked to rubber dam use, and to graduation cohort. Seventy-one per cent of rubber dam users irrigated with sodium hypochlorite, compared with only 38% of nonusers. This pattern was reversed for local anaesthetic irrigation. Younger graduates were significantly more likely to irrigate with local anaesthetic solution than their older counterparts, and the younger graduates of one school showed a highly significant increase in the use of chlorhexidine. Conclusions 1) The majority of UK Health Service dentists never use rubber dam isolation in endodontic treatment. 2) Qualifying school has a significant impact on rubber dam use, and irrigant selection. 3) Use of rubber dam has a significant association with irrigant choice in endodontics.

Solvent-free oxidation of benzyl alcohol to benzaldehyde by tert-butyl hydroperoxide using transition metal containing layered double hydroxides and/or mixed hydroxides

Abstract: Performance of Mn-Al, Co-Al, Ni-Al, Zn-Al, Mg-Fe, Mn-Fe, Co-Fe, Ni-Fe, Mn-Cr, Co-Cr, Ni-Cr, Cu-Cr, and Zn-Cr layered double hydroxides (LDH) and/or mixed hydroxides (HD) solid catalysts has been evaluated for the liquid phase oxidation of benzyl alcohol to benzaldehyde using TBHP as an oxidizing agent in the absence of any solvent The Mn, Cu, and Co containing LDH solids show good catalytic activity in the oxidation and hence these are promising catalysts for the solvent-free oxidation of benzyl alcohol to benzaldehyde

Nanostructured spinel ZnCo2O4 for the detection of LPG

Abstract: Nanostrucutred spinel ZnCo 2 O 4 (∼26–30 nm) was synthesized by calcining the mixed precursor (consisting of cobalt hydroxyl carbonate and zinc hydroxyl carbonate) in air at 600 °C for 5 h. The mixed precursor was prepared through a low cost and simple co-precipitation/digestion method. The transformation of the mixed precursor into nanostructured spinel ZnCo 2 O 4 upon calcinations was confirmed by X-ray diffraction (XRD) measurement, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM). To demonstrate the potential applicability of ZnCo 2 O 4 spinel in the fabrication of gas sensors, its LPG sensing characteristics were systematically investigated. The ZnCo 2 O 4 spinel exhibited outstanding gas sensing characteristics such as, higher gas response (∼72–50 ppm LPG gas at 350 °C), response time (∼85–90 s), recovery time (∼75–80 s), excellent repeatability, good selectivity and relatively lower operating temperature (∼350 °C). The experimental results demonstrated that the nanostructured spinel ZnCo 2 O 4 is a very promising material for the fabrication of LPG sensors with good sensing characteristics. Plausible LPG sensing mechanism is also discussed.