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Abstract  

Transition metal dithiocarbamate complexes, [M(S2CN(C2H5)(CH2CH2OH)] (M=Co, Ni, Cu, Zn and Cd) have been prepared and characterized by elemental analysis and infrared spectra. Thermal decomposition of all the complexes occurs in two or three stages. The first stage in all the complexes is always fast with 65-70% mass loss. In all cases the end product is metal oxide except in the case of cobalt complex which gives Co metal as an end product. During decomposition of copper complex, first CuS is formed at ~300C which is converted into CuSO4 and finally CuO is formed. However, decomposition in helium atmosphere yields CuS. SEM studies of transition metal dithiocarbamates reveal needle shape crystalline phase at room temperature and formation of metal sulphide/oxide at higher temperatures. The activation energy varies in a large range of 33.8-188.3 kJ mol-1, being minimum for the Cu complex and maximum for the Zn complex possibly due to d 10 configuration. In the case of Ni, Zn and Cd complexes the order of reaction is two suggesting bimolecular process involving intermolecular rearrangement. However, in other cases it is a unimolecular process. Large negative values of ΔS # for all the complexes suggest that the decomposition process involves rearrangement.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, Monica Dan, Maria Mihet, Alexandru R. Biris, Petru Marginean, Valer Almasan, George Borodi, Fumiya Watanabe, Alexandru S. Biris, and Mihaela D. Lazar

) ( Eq. 2 ). (1) (2) Steam reforming is preferred to other reforming processes because it provides the highest quantity of hydrogen in the product stream [ 2 , 3 ]. MSR can be catalyzed by several transition metals, usually supported on oxides. The

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. parahaemolyticus in shrimp ( Wrıuht et al., 2016 ; Fang et al., 2018 ). S. putrefaciens is a major food spoilage bacterium in seafood, and exhibits a higher resistance to antibiotics and metals ( Kanu & So, 2016 ), but rarely implicated as a cause of human

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://apps.fao.org FAO Statistical Databases 2005 Foy, C. D., Chaney, P. L., White, M. C. (1978) The physiology of metal toxicity in plants

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Abstract  

The effects of different concentrations of metals (Ni, Cu, Cd, Zn) on the reactivity of carbon towards air were studied by means of TG and DTA. It was observed that these metals are capable of decreasing the ignition temperature and increasing the mass loss. Activation energies calculated by Horowitz's method revealed that these metals promote the combustion of active carbon.

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Transition metal complexes of heterocyclic Schiff base

Biological activity, spectroscopic and thermal characterization

Journal of Thermal Analysis and Calorimetry
Authors: M. Omar, G. Mohamed, and A. Hindy

Abstract  

Metal complexes of Schiff base derived from 2-furancarboxaldehyde and 2-aminobenzoic acid (HL) are reported and characterized based on elemental analyses, IR, 1H NMR, UV-Vis, solid reflectance, magnetic moment, molar conductance and thermal analysis. The ligand dissociation as well as the metal-ligand stability constants have been calculated pH-metrically at 25C and ionic strength μ=0.1 (1 M NaCl). The complexes are found to have the formulae [M(HL)2](X)n yH2O (where M=Fe(III) (X=Cl, n=3, y=4), Co(II) (X=Cl, n=y=2), Ni(II) (X=Cl, n=y=2), Cu(II) (X=Cl, n=y=2) and Zn(II) (X=AcO, n=y=2)) and [UO2(L)2]2H2O. The thermal behaviour of these chelates is studied and the activation thermodynamic parameters are calculated using Coats-Redfern method. The ligand and its metal complexes show a biological activity against some bacterial species.

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Abstract  

PIXE studies on pure metal targets surrounded by insulating material produced enhanced X-ray yields at comparatively low proton energies. Specially prepared metal discs of selected transition elements were embedded in Macor target holders and irradiated with 700 keV protons. Improved X-ray yields of up to more than 300% were observed. It was found that the enhanced yields were affected by the incident beam current due to a “leakage” effect. The recorded time-dependent spectra showed similar charge build-up and discharge patterns as those originally obtained for non-conducting samples. A possible mechanism for the enhancement is discussed.

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Abstract  

Vegetable tannin sorbent is evaluated as ion exchange resin using a multitracer study on the adsorption behavior of various elements. Lisiloma latisiliqua L. tannins, polycondensated into spherical pellets were chosen as sorbent resin material. Sorption evaluation of Ce, Cu(II), U(VI), Eu, Fe(III), Th, Nd as representatives of different classes of metal ions were done at different pH values. The distribution ratio of the studied elements was calculated from laboratory experiments. Tannic ion exchange material shows excellent ability for actinides and rare earth elements adsorption from waters. Using radiotracers, the number of catechins subunits involve in each tannin-metal complex was determined.

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Abstract  

Research into a new method for separating palladium from rhodium, based on radiochemical principles, necessitated a re-investigation of the Gmelins Handbuch data indicating that Rh has allotropes. Two independent and different methods were used, which both yielded the same results; i.e. that no allotropy can be found. Non-ambient temperature X-ray diffraction (HT-XRD) did not show any difference in the diffractograms due to phase transformation of Rh-metal at elevated temperatures. Differential thermal analysis (DTA) confirmed the HT-XRD result in the temperature range of 1000–1400 °C. In conclusion, the absence of allotropy of the metal rhodium was proven.

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conditions. The main objective of the present article is to apply thermal analysis directly in the thermal centre of castings solidified in resin sand and metal moulds (MM), and use the reference Quik-cup™ system, for the same cooling modulus (CM = 0

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