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Tris(ethylenediamine)cobalt(II) sulfate
Bunlawee Yotnoi,Athittaya Seeharaj,Yothin Chimupala,Apinpus Rujiwatra
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810016168
Abstract: The structure of the title compound, [CoII(C2H8N2)3]SO4, the cobalt example of [M(C2H8N2)3]SO4, is reported. The Co and S atoms are located at the 2d and 2c Wyckoff sites (point symmetry 32), respectively. The Co atom is coordinated by six N atoms of three chelating ethylenediamine molecules generated from half of the ethylenediamine molecule in the asymmetric unit. The O atoms of the sulfate anion are disordered mostly over two crystallographic sites. The third disorder site of O (site symmetry 3) has a site occupancy approaching zero. The H atoms of the ethylenediamine molecules interact with the sulfate anions via intermolecular N—H...O hydrogen-bonding interactions.
INFLUENCE OF COBALT IONS ON ENZYME ACTIVTY OF ISOCITRIATE LYASE AND ITS REGULATION IN CONDITION OF SEED GERMINATION OF GLYCINE MAX L.
Chechui O. F.
Bìologì?nij Vìsnik Melìtopol?s?kogo Der?avnogo Pedagogì?nogo Universitetu ìmenì Bogdana Hmel?nic?kogo , 2012,
Abstract: We investigated the activity of isocitrate lyase in seeds of Glycine max L. after 24, 72, and 120 hours of germination and effect of cobalt ions on the activity of the enzyme in time limit of the experiment. We fixed the increase in the activity of isocitrate lyase under influence of cobalt ions occurs by means of enzyme induction on third day of experiment while maintaining performance of enzyme activity on the fifth day; one of the reasons caused the increased activity of the key enzyme of the glyoxylate cycle under the influence of cobalt ions can be increasing of the concentration of lipid peroxidation. In addition, during experiments with usage of actinomycin D we determined the increasing of activity ofisocitrate lyase under the influence of cobalt ions by enzyme induction.
Effect of Hydroxylamine Sulfate on Volumetric Behavior of Glycine, L-Alanine, and L-Arginine in Aqueous Solution  [PDF]
Jie Chen,Sheng Fang,Yu-Gang Shi,Yue-Cheng Meng,Da-Hai Ren
Journal of Chemistry , 2013, DOI: 10.1155/2013/481341
Abstract: The apparent molar volumes of glycine, L-alanine, and L-arginine in aqueous hydroxylamine sulfate solutions have been determined at ?K and atmospheric pressure. The standard partial molar volumes, , corresponding partial molar volumes of transfer, , and hydration numbers, , have been calculated for these α-amino acids from the experimental data. The values are positive for glycine, L-alanine, and L-arginine and are all increased with the increase in the concentration of hydroxylamine ions. These parameters obtained from the volumetric data are interpreted in terms of various mixing effects between amino acids and hydroxylamine sulfate in aqueous solutions. 1. Introduction In recent years, the denaturation and renaturation behavior of biological molecules such as proteins in aqueous solutions has been the subject of extensive investigation [1–3]. However, the complex configurational and conformational factors affecting the structure of protein in aqueous solutions make the direct interpretation from studies on proteins very difficult [4]. Volumetric and transport properties of amino acids such as density and viscosity have been extensively investigated and can provide valuable information for conformational stability and unfolding behavior of globular proteins in aqueous solutions [5–13]. It is well recognized that inorganic and organic salts can produce remarkable effects on the conformation and properties of proteins in aqueous solutions. Hydroxylamine derivatives are always used by biologists for their ability to introduce random mutations by switching different base pairs [14]. Hydroxylamine can also be applied to selectively cleave peptide bonds in peptides and proteins [15]. The highly biological activities of hydroxylamine derivatives make it quite interesting to study the behaviour of proteins in the presence of hydroxylamine salts [16]. Consequently, the knowledge of thermophysical and thermodynamic properties of hydroxylamine with small molecules will be required and useful for obtaining information about various interactions occurring in aqueous hydroxylamine solutions with macromolecules. In this study, we present experimental densities of glycine, L-alanine, and L-arginine in aqueous and aqueous hydroxylamine sulfate solutions of (0.10, 0.25, and 0.40) mol?kg?1 at ?K and atmospheric pressure. From these data, the standard partial molar volumes ( ), standard partial molar volumes of transfer ( ), and molar hydration number ( ) have been calculated. The results are discussed in terms of various solute-solute interactions and also their nature
Heat Capacity in Magnetic and Electric Fields Near the Ferroelectric Transition in Tri-Glycine Sulfate  [PDF]
J. C. Lashley,C. P. Opeil,T. R. Finlayson,R. A. Fisher,N. Hur,M. F. Hundley,B. Mihaila,J. L. Smith
Physics , 2007, DOI: 10.1063/1.2435333
Abstract: Specific-heat measurements are reported near the Curie temperature ($T_C$~= 320 K) on tri-glycine sulfate. Measurements were made on crystals whose surfaces were either non-grounded or short-circuited, and were carried out in magnetic fields up to 9 T and electric fields up to 220 V/cm. In non-grounded crystals we find that the shape of the specific-heat anomaly near $T_C$ is thermally broadened. However, the anomaly changes to the characteristic sharp $\lambda$-shape expected for a continuous transition with the application of either a magnetic field or an electric field. In crystals whose surfaces were short-circuited with gold, the characteristic $\lambda$-shape appeared in the absence of an external field. This effect enabled a determination of the critical exponents above and below $T_C$, and may be understood on the basis that the surface charge originating from the pyroelectric coefficient, $dP/dT$, behaves as if shorted by external magnetic or electric fields.
Does a glycine sodium nitrite crystal exist?  [PDF]
Kiran T. Dhavskar,Bikshandarkoil R. Srinivasan
Physics , 2015,
Abstract: The glycine sodium nitrite crystal reported by Khandpekar and Pati in the paper entitled, Synthesis and characterisation of glycine sodium nitrite crystals having non linear optical behaviour, Opt Commun 285, 2012 288-293 is actually gamma-glycine. In addition, we show that glycine barium ammonium nitrate, glycine sodium zinc sulfate, glycine barium calcium nitrate, glycine acetamide and glycine dimer are dubious crystals.
Direct Fabrication of Cobalt Oxide Nano-particles Employing Glycine as a Combustion Fuel
Physical Chemistry , 2012, DOI: 10.5923/j.pc.20120206.01
Abstract: Combustion method has been used as a fast and facile method to prepare nanocrystalline Co3O4 spinel employing glycine as a combustion fuel. The products were characterized by thermal analyses (TGA & DTA), X-ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM) techniques. Experimental results revealed that the molar ratio of fuel/oxidant play an important role in controlling the crystallite size of Co3O4 nanoparticles. Transmission electron microscopy indicated that the crystallite size of Co3O4 nanocrystals were in the range of 14–31 nm. Since the particle size of the powdered samples were found to be equivalent from both TEM and X-ray diffraction technique. X-ray diffraction confirmed the formation of CoO phase with spinel Co3O4. The effect of calcination temperature on crystallite size and morphology has been discussed.
Cobalt electrodeposition onto highly oriented pyrolytic graphite (HOPG) electrode from ammonium sulfate solutions
Mendoza-Huizar, Luis Humberto;Rios-Reyes, Clara Hilda;Rivera, Margarita;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000500019
Abstract: it was carried out an electrochemical study of the cobalt electrodeposition onto hopg electrode from an aqueous solution containing 10-2 m of coso4 + 1m (nh4)2so4. nucleation parameters such as nucleation rate, density of active nucleation sites, saturation nucleus and the rate constant of the proton reduction reaction (kpr) were determined from potentiostatic studies. an increase in kpr values with the decrease in the applied potential suggested a competition between h+ and co2+ by the active sites on the surface. the δg energy calculated for the formation of stable nucleus was 8.21x10-21 j/nuclei. the afm study indicated the formation of small clusters of 50-400 nm in diameter and 2-120 nm in height.
Kinetic study of the cobalt electrodeposition onto glassy carbon electrode from ammonium sulfate solutions
Rios-Reyes, Clara Hilda;Granados-Neri, Madaí;Mendoza-Huizar, Luis Humberto;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000900028
Abstract: we carried out an electrochemical study of the cobalt electrodeposition onto glassy carbon electrode from an aqueous solution containing 10-2 m of coso4 + 1 m (nh4)2so4 at natural ph 4.5. the potentiostatic study indicated a progressive 3d nucleation and growth during the deposition process. the average diffusion coefficient calculated for this system was 2.65 x 10-6 cm2 s-1 while the δg for the formation of stable nucleus was 6.50 x 10-20 j/nuclei. the scanning electron microscopy images indicated the formation of small and homogeneous nucleus onto gce of approximately 300 nm.
Effects of Added Chloride Ion on Electrodeposition of Copper from a Simulated Acidic Sulfate Bath Containing Cobalt Ions  [PDF]
Bijayalaxmi Panda
ISRN Metallurgy , 2013, DOI: 10.1155/2013/930890
Abstract: The effects of added chloride ion on copper electrodeposition was studied using Pb-Sb anode and a stainless steel cathode in an acidic sulfate bath containing added Co2+ ion. The presence of added chloride ion in the electrolyte solution containing 150?ppm of Co2+ ion was found to increase the anode and the cell potentials and decrease the cathode potential. Linear sweep voltammetry (LSV) was used to study the effects of added chloride ion on the anodic process during the electrodeposition of copper in the presence of added ?ppm; the oxygen evolution potential is polarised by adding 10?ppm chloride ion at current densities (≥150?A/m2), and further increase in chloride ion concentration increases the polarisation of oxygen evolution reaction more at higher current densities. X-ray diffraction (XRD) showed that added chloride ion and added Co2+ ion changed the preferred crystal orientations of the copper deposits differently. Scanning electron microscopy (SEM) indicated that the surface morphology of the copper deposited in the presence of added chloride ion and added Co2+ ion has well-defined grains. 1. Introduction Copper is generally extracted through pyrometallurgical processes [1]. However several important factors such as nonavailability/depletion of high-grade ores, increasing world demand, increasing process cost like labour cost, energy cost, and so forth, and emission of highly toxic and strongly acidic sulfur-oxide gases from smelter plants creating severe environmental pollution demanded an alternative technology to overcome these problems towards the end of nineteenth century. Thus in mid of 1980, hydrometallurgical processes involving leaching, solvent extraction, and electrowinning (L/SX/EW) were widely adopted for extraction of copper from secondary sources such as oxide ores, mixed sulfide and oxide ores, low grade sulfide ores, industrial wastes from metal plating, metal finishing, wastes from metallurgical industries, scrap copper, and alloys [1]. Although copper leaching and solvent extraction have achieved a state of advanced development, the commercial success of the process is dependent upon the ability to produce high-quality final product through the electrowinning process. The high power consumption associated with this process has been the subject of many investigations in the last few years [2–6]. The attempts made so far are [7](a)improvement in mass transport for cell operation at higher-current density without significant increase in energy requirement,(b)selection of different routes for production of the copper
Effect of Cesium–137 Gamma Rays and High-Energy Electrons on Dose Response of Glycine Dosimeter  [cached]
Santosh H. Shinde,T. Mukherjee
Journal of Scientific Review , 2010,
Abstract: Glycine (50 mg / 10 mL FX) system can be used in the dose range of 500 to 4000 Gy for Cobalt-60 gamma rays. The energy dependency study for the glycine system was carried out by comparing its dose response for Cesium–137 gamma rays and 7 MeV electron beam with the dose response for Cobalt-60 gamma rays. It was found that for both the radiations viz.: Cesium-137 gamma rays and electrons, there is no significant change in dose response as compared with that for Cobalt-60.
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