NOPR Collection:

Solvation of N-based cationic polyelectrolytes : Viscosity studies in propylene carbonate and sulpholane

2013-09-18T16:33:33Z

Title: Solvation of N-based cationic polyelectrolytes : Viscosity studies in propylene carbonate and sulpholane Authors: Singh, Meenakshi; Kumar, Anil; Prasad, B B Abstract: Viscosities of a few cationic polyelectrolytes possessing N-alkyl/N-acyl ammonium and 2,5-thiophenylene linkages in their respective repeating units of the chain (mol. wt. 1154-3815) have been studied in two dipolar aprotic solvents, viz. propylene carbonate (PC) and sulpholane. The results are treated on the basis of Fuoss-Strauss equation. The intrinsic viscosities obtained from Fuoss-Strauss equation, in conjunction with the derived parameters such as characteristic ratio (C_∞), maximum cross-dimension (), root mean square end-to-end distance (< Rg² >^1/2) and plane projection distance (P) are invoked to comprehend polycationic hydrodynamic models in both solvents. Page(s): 489-494

Analysis of sub-boil distilled water, hydrochloric and nitric acid for trace element impurities by ICP-MS

2013-09-16T16:35:42Z

Title: Analysis of sub-boil distilled water, hydrochloric and nitric acid for trace element impurities by ICP-MS Authors: Balaram, V; Chandrasekhar, K; Agrawal, A K; Sharma, P N; Ganju, Sunita; Rao, T.Nageswara; Anjaiah, K.V.; Husain, Sajid; Lal, Krishan Abstract: A method has been designed for the precise estimation of a few trace and ultra-trace elements in high purity sub-boil distilled water and hydrochloric and nitric acids using inductively coupled plasma mass spectrometers of two different makes. The trace element concentrations of majority of the elements analysed in sub-boil distilled water are found to be below detection limits. A comparison of the trace element impurity levels obtained in hydrochloric and nitric acids with the maximum allowable impurity levels for high purity reagents documented in SEMI, suggests that these purity levels confirm with the specifications given for the high pure reagents. Page(s): 567-570

Column chromatographic preconcentration of cobalt and zinc with 3-hydroxy-4-imino(N-2' -pyridyl)-2-methylnaphthalen-1-one adsorbed on naphthalene and their estimation in vitamin and milk samples

2013-09-16T16:34:18Z

Title: Column chromatographic preconcentration of cobalt and zinc with 3-hydroxy-4-imino(N-2' -pyridyl)-2-methylnaphthalen-1-one adsorbed on naphthalene and their estimation in vitamin and milk samples Authors: Garg, B S; Sharma, R K; Bist, J S; Bhojak, N; Mittal, Sachin; Sindhwani, Shallu Abstract: A sensitive, economical and rapid spectrophotometric method of preconcentration and separation of cobalt and zinc has been developed using a solid chelating resin, 3-hydroxy- 4-imino-(N-2' -pyridyl)-2-methylnaphthalen-1-one (HIPMN) supported on naphthalene. Co and Zn are quantitatively determined using this absorbent in a column in the pH range of 4.0-6.0 and 5.8-8.0 respectively with a now rate of 2 ml min^-1.The metal complex and naphthalene are dissolved out from the column with 10 ml of DMF and the absorbance is measured at 568.5 nm and 466 nm for Co and Zn, respectively. Beer's law is obeyed up to 15 mg l^-¹, for Co and 22 mg l^-¹ for Zn using this method with a sensitivity of 0.035μg cm^-2 for Co and 0.032μg cm^-2 for Zn for log (I₀/I) =0.001. Atomic absorption spectrometry (AAS) is also used to determine the metal ion concentration. Page(s): 564-566

Trace metals analysis in molybdenite mineral sample

2013-09-17T16:34:56Z

Title: Trace metals analysis in molybdenite mineral sample Authors: Tamrakar, Praveen Kumar; Pitre, K S Abstract: DC polarography and other related techniques, viz., DPP and DPASV have been sucessfully used for the simultaneous determination of trace metals in. molybdenite mineral sample. The polarograms and voltammograms of sample solution have been recorded in 0.1 M (NH₄)₂ tartrate supporting electrolyte at two different pH values i.e., 2.7 ±0.1 and 9.0 ± 0.1. The results indicate the presence of Cu²⁺, Mo⁶⁺,Cd²⁺ Ni²⁺ ,In³⁺, Fe³⁺ and W⁶⁺ metal ions in the sample. For the determination of tungsten(VI), 11 M HCl has been used as supporting electrolyte. Tungsten(VI) produces a well defined wave/peak with E_1/2/E_P=-0.42V/-0.48V vs SCE in 11 M HCl. The quantitative analysis by the method of standard addition shows the mineral sample to have the following composition, Cu²⁺ (14.83), Mo⁶⁺ (253.70), Cd²⁺ (41.36), Ni²⁺ (16.08), In³⁺(3.06), Fe³⁺ (83.00) and W⁶⁺ (4.14 )mg/g of the sample. Statistical treatment of the observed voltammetric data reveals high accuracy and good precision of determination. The observed voltammetric results are comparable with those obtained using AAS method. Page(s): 560-563