Electrochemical reactions at sacrificial electrodes: Part VI-Synthesis of cadmium alkoxides and their coordination compounds

895-897Cadmium alkoxides [Cd(OR)2; R = methyl, ethyl, n-propyl, n-butyl and n-amyl], have been synthesised by the electrolysis of alcohols at a cadmium anode. These alkoxides do not form coordination compounds when refluxed with the ligands like 2, 2' -bipyridine, 1, 10-phenanthroline, dimethylsulphoxide and acetone. However, coordination compounds with the general formula, Cd(OR)2.L, have been prepared when the solutions of these ligands in alcohols are electrolysed at a cadmium anode. The products have been characterised by elemental analyses and IR data. Current efficiencies of all these systems are quite high

Electrochemical reactions at sacrificial electrodes: Synthesis of zinc(II) alkoxides. Part XVII

266-268Electrochemical reactions of various alcohols have been carried out at sacrificial zinc anode and inert platinum cathode using tetrabutylammonium chloride as supporting electrolyte and acetonitrile as solvent. Solid products obtained from the anode compartment have been identified as zinc(II) alkoxides by elemental analysis and infrared spectral data. The current efficiencies of these systems have been found to be very high

Physico-chemical studies in non-aqueous solvents. X. Conductance and solvation studies of 1:1 electrolytes in N,N-dimethylacetamide

Conductances of some 1:1 electrolytes have been measured in the concentration range 1-120×10−4 mol l−1 in N,N-dimethylacetamide at 25°. The conductance data have been analysed by Fuoss-Onsager-Skinner equations for dissociated and associated electrolytes, and limiting equivalent conductances, ion-size parameter and association constants (where appropriate) for various electrolytes have been obtained. The ion-size parameter (3.7±0.3Å) has been found to be about the same for all the electrolytes. Alkali metal salts are fully dissociated while the substituted ammonium salts are slightly associated in this solvent. The ionic association increases with increase in the size of cations. Transference numbers of lithium chloride, potassium thiocyanate and silver perchlorate have also been measured in the concentration range 1.1-18.4×10−2mol l−1 in this solvent. Limiting cation transference numbers are determined from the linear plots of cation transference numbers against square root of concentration. Ionic mobilities, effective ionic radii and solvation numbers of various ions in solution have been calculated. Higher solvation numbers of cations than those of anions of comparable sizes are consistent with the aprotic nature of the solvent

Physico-chemical studies in Non-aqueous solvents: Part XIX – Viscosity Studies of Some 1:1 Electrolytes in Tetramethylurea

797-79

Transference number and solvation studies in tetramethylurea

Transference numbers of sodium and potassium thiocyanate, have been measured in tetramethylurea at 25°C by a modified Hittorf's method in the concentration range 1.5-9.4×10-2 M. A linear relationship is observed between the cation transference number and the square root of the concentration. Combining the limiting transference numbers and limiting equivalent conductances of these two salts, ionic mobilities of sodium, potassium, and thiocyanate ions have been found to be 16.08, 15.73, and 33.04 ohm-1 cm2 mol-1, respectively. From these values ionic mobilities of other univalent ions, effective ionic radii, and solvatlon numbers have been computed. Higher solvation of cations than of anions of comparable sizes is consistent with the aprotic nature of the solvent

Prevalence of gastro-esophageal reflux disease in patients with difficult to control asthma and effect of proton pump inhibitor therapy on asthma symptoms, reflux symptoms, pulmonary function and requirement for asthma medications

Background: The hypothesis that GER can trigger or exacerbate asthma is supported by several clinical trials that have shown amelioration in asthma symptoms and/or an improvement in pulmonary function after antireflux therapy. Aims: To investigate the prevalence of GER in patients with difficult to control asthma and to determine the effect of omeprazole on asthma symptoms, reflux symptoms, pulmonary function and on the requirement of asthma medications. Materials and Methods: Patients with difficult to control asthma were recruited into the study. All patients underwent esophageal manometry and 24 hour esophageal pH monitoring. Pulmonary function tests were done before and after treatment. The severity of asthma and reflux was assessed by a 1 week pulmonary symptom score(PSS) and reflux symptom score(RSS) respectively before and after treatment. Those who had an abnormal pH study (pH 5% of the time) underwent anti-GER treatment with lifestyle changes, and a proton pump inhibitor (omeprazole 40 mg, bid) for 3 months. Asthma medications were added or deleted based on severity of asthma. Results: Out of 250 asthmatic patients screened, forty patients fulfilled the inclusion criteria. Twenty eight of 40 patients(70%) were diagnosed to have GERD. Of the patients 28 with GER, 8 patients(28.5%) had no reflux symptoms. On 24 hr pH metry, the percentage time pH <4.0 was 10.81 ± 4.72 and 1.11 ± 1.21; Deemester score was 37.65 ± 14.54 and 4.89 ± 6.39 (p-value is 0.0001) in GERD and non-GERD patients respectively.In GERD group, post treatment reflux symptom score(RSS) improved from 22.39 ± 14.99 to 1.04 ± 1.07, pulmonary symptom score(PSS) improved from27.14 ± 7.49 to 13.82 ± 4.21and night time asthma symptom score(NASS) improved from 6.71 ± 1.80 to 3.04 ± 1.23 (p-value <0.0001). After treatment, FEV1 and PEFR increased from 1.38 ± 0.57 and 4.14 ± 1.97 to 1.47 ± 0.54 and 5.56 ± 1.72, respectively (p-value 0.00114). Conclusions: PPI therapy improves nocturnal asthma symptoms, daytime asthma symptoms, pulmonary function and decreases requirement of asthma medications in these patients