Heat pipes: progress in thermal performance enhancement for microelectronics

Journal of Thermal Analysis and Calorimetry - The aim of this study is to oversee the impact of various techniques on thermal performance of heat pipes and to comprehensively cover the progress...     

Single nucleon distribution based on shell-model and matrix ensemble theory

An expression for the density of single nucleons in a heavy spherical nucleus is derived using the shell-model and matrix ensembles. It is shown that the theoretical expression gives an excellent fit to the density of nucleons for the nucleus¹⁹⁷Au obtained usinge-scattering data.     

Exact generator coordinate wave functions for some simple hamiltonians

We obtain the superconformal transformation laws of theN=4 supersymmetric Yang-Mills theory and explicitly demonstrate the closure of the algebra.     

Synthesis,characterization and biological analysis of transition metal complexes with macro cyclic ligands derived from adipic acid,ethylenediamine with diethyloxalate and diethylmalonate

Macro-cyclic ligands from adipic acid, ethylenediamine with diethyloxalate and diethylmalonate and their respective metal complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with macro cyclic ligands (LO) and (LM) L [N,N′-bis(2-aminoethyl)hexanediamide] were synthesized successfully. These metal complexes were characterized by Fourier transform infrared, ultraviolet visible spectrometry, proton nuclear magnetic resonance spectroscopy, and mass Spectrometry, CHNS and thermogravimetric analysis. The elemental analysis confirms the structures for Mn(II), Co(II) and Ni(II) complexes similar to octahedral geometry, Cu(II) complexes as a square planar geometry and Zn(II) complexes in the tetrahedral geometry. The molar conductivities of all the metal complexes were taken in 10^?3 M DMSO, and values of all the metal complexes showed their electrolytic nature which indicates the presence of chloride ions. Thermal analysis supports as the metal complexes are thermally stable. The result of antimicrobial activity against various microorganisms confirms that the metal complexes are potent bactericides and fungicides than the ligand. Metal complexes of LO with Cu(II) and Zn(II) were found to be highly active against S. typhimurium than the complexes of LM.

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Estimation of Residual Nickel and Some Heavy Metals in Vanaspati Ghee

To convert vegetable edible oils into vanaspati ghee, nickel is used as a catalyst in the hydrogenation process. A simple and fast method for the trace level determination of nickel in ghee is reported. In this work different methods were applied for the extraction of residual nickel from ghee samples. Using toluene, benzene and carbon tetrachloride as organic solvents, an acid mixture was used for the extraction of nickel. Extracted nickel was quantified with atomic absorption and colorimetric methods. Among the organic solvents, toluene proved to be the best solvent mediating a 95% extraction of nickel from ghee samples. Nickel was extracted and determined in ten different brands of ghee and in all samples its amount was well above the permissible limit of WHO (0.2 μg/g). Other metals like lead, zinc, copper, and cadmium were also determined and their concentrations were found to be much below the WHO permissible limits.     

Ensemble average of an arbitrary number of pairs of different eigenvalues using Grassmann integration

An identity satisfied by the eigenvalues of a real-symmetric matrix and an integral representation of a determinant using Grassmann variables are used to show that the ensemble average ofS different pairs of eigenvalues of a GOE is given by (–1) ^S 2^{–S –1/2}(S+1/2).     

Spectrophotometric Determination of Prochlorperazine Maleate in Pure and Pharmaceutical Preparations

 Prochlorperazine maleate reacts with 1-naphthylamine and sodium nitrite, after heating for 110 s at 80 °C to give an orange red colour having maximum absorbance at 460 nm. The reaction is selective for prochlorperazine maleate with 0.01 mg/mL as visual limit of quantitation and provides a basis for a new spectrophotometric determination. The colour reaction obeys Beer’s law from 0.01 mg/10 mL to 0.33 mg/10 mL of prochlorperazine maleate and the relative standard deviation is 0.68%. The quantitative assessment of tolerable amounts of other drugs is also studied. Received September 22, 2000. Revision June 19, 2001     

2020 Roadmap on gas-involved photo-and electro-catalysis

In this roadmap, we address the development and perspectives of hydrogen evolution reaction, oxygen reduction reaction, oxygen evolution reaction, carbon dioxide reduction reaction and nitrogen reduction.     

Indirect Atomic Absorption Determination of Cocaine via Formation and Liquid‐liquid Extraction of the Iron(III)‐cocaine Complex

The principles of metal‐alkaloid ion‐pair formation and liquid‐liquid extraction are applied to the development of a sensitive and convenient atomic absorption spectrophotometery (AAS) method for the indirect determination of cocaine. In an aqueous medium of 5 M hydrochloric acid, cocaine is protonated and is associated with tetrachloro ferrate (III) anion prior to its extraction into 1,2‐dichloroethane. The critical experimental variables were identified and optimized. The method is simple and reproducible with a detection limit (DL) of 0.1 ng cm^?3 cocaine in water, a relative standard deviation of 0.07 (n = 12), and the calibration graph was linear up to 50 ng cm^?3 cocaine.