Residual stress measurement round robin on an electron beam welded joint between austenitic stainless steel 316L(N) and ferritic steel P91

This paper is a research output of DMW-Creep project which is part of a national UK programme through the RCUK Energy programme and India's Department of Atomic Energy. The research is focussed on understanding the characteristics of welded joints between austenitic stainless steel and ferritic steel that are widely used in many nuclear power generating plants and petrochemical industries as well as conventional coal and gas-fired power systems. The members of the DMW-Creep project have under- taken parallel round robin activities measuring the residual stresses generated by a dissimilar metal weld (DMW) between AISI 316L(N) austenitic stainless steel and P91 ferritic-martensitic steel. Electron beam (EB) welding was employed to produce a single bead weld on a plate specimen and an additional smoothing pass (known cosmetic pass) was then introduced using a defocused beam. The welding re- sidual stresses have been measured by five experimental methods including (I) neutron diffraction (ND), (II) X-Ray diffraction (XRD), (III) contour method (CM), (IV) incremental deep hole drilling (iDHD) and (V) incremental centre hole drilling (iCHD). The round robin measurements of weld residual stresses are compared in order to characterise surface and sub-surface residual stresses comprehensively

Analytical Method Development and Validation of Stability Indicating RP-HPLC Method for The Simultaneous Estimation of Dolutegravir, Emtricitabine and Tenofovir Disproxil Fumarate

A simple, Accurate, precise method was developed for the simultaneous estimation of the Dolutegravir (DUA), Emtricitabine(ECB) and Tenofovir Disoproxil fumarate (TDF) tablet dosage form. Chromatogram was run through Std Kinetex Biphenyl, 250 x 4.6 mm, 5µm. Mobile phase-A containing pH-3.0 Ammonium acetate Buffer & Mobile phase -B containing Degassed mixture of Acetonitrile & Methanol taken in the ratio of 50:50 was pumped through column at a flow rate of 1 mL/min. Diluent used in this method was 0.1% Orthophosphoric acid buffer & Methanol in the ratio of 50:50%v/v. Temperature was maintained at 40°C. Optimized wavelength selected was 260 nm. Retention time of DUA, ECB and TDF were found to be 14.6min, 3.98min and 12.60min. %RSD of the DUA, ECB and TDF were found to be 0.35, 0.47 & 0.40 respectively. %Recovery was obtained as 98.9%, 99.6% and 99.3% for DUA, ECB and TDF respectively. Both the runtime and retention times were decreased, so this method developed was simple and economical this can be adopted in regular quality control in pharma industries

Comparison of 4-chloro-2-nitrophenol adsorption on single-walled and multi-walled carbon nanotubes

<p>Abstract</p> <p>The adsorption characteristics of 4-chloro-2-nitrophenol (4C2NP) onto single-walled and multi-walled carbon nanotubes (SWCNTs and MWCNTs) from aqueous solution were investigated with respect to the changes in the contact time, pH of solution, carbon nanotubes dosage and initial 4C2NP concentration. Experimental results showed that the adsorption efficiency of 4C2NP by carbon nanotubes (both of SWCNTs and MWCNTs) increased with increasing the initial 4C2NP concentration. The maximum adsorption took place in the pH range of 2–6. The linear correlation coefficients of different isotherm models were obtained. Results revealed that the Langmuir isotherm fitted the experimental data better than the others and based on the Langmuir model equation, maximum adsorption capacity of 4C2NP onto SWCNTs and MWCNTs were 1.44 and 4.42 mg/g, respectively. The observed changes in the standard Gibbs free energy, standard enthalpy and standard entropy showed that the adsorption of 4C2NP onto SWCNTs and MWCNTs is spontaneous and exothermic in the temperature range of 298–328 K.</p