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compressibility) of the powder was insufficient. In this case, therefore, intermediates must be prepared [ 12 ]. This was also a very difficult step, since the applied components are not appropriate for wet granulation. Sodium bicarbonate is sensitive to water

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Acta Chromatographica
Authors: Mohammad Al Bratty, Neelaveni Thangavel, Ramalingam Peraman, Vinod Kumar, Padmanabha Reddy, Krishna Veni Nagappan, and Hassan Al Hazmi

Intermediate precision 10 μg/mL: 1.11% (RSD) <2% / Pass 15 μg/mL: 1.23% (RSD) <2% / Pass 20 μg/mL: 1

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bifluoride at room temperature gave (NH 4 ) 3 YF 6 ·1.5H 2 O, which decomposed between 80 and 320 °C to form YF 3 by losing NH 4 F and H 2 O. Kalinnikov et al. [ 7 ] reported that the reaction between yttria and ammonium bifluoride yields the intermediates

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Conclusions PVAc/epoxy thermosets are phase separated, arising two phases that correspond to a PVAc-rich phase and to the epoxy rich-phase. The morphology evolves from nodular to inverted as the PVAc content increases. Intermediate compositions (10

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suitable methods and a series of photocatalytic experiments were conducted to examine their catalytic activity on the degradation of chlorpyrifos. The intermediate products formed in the photodegradation process were analyzed by GC–MS techniques

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(I,II) = 9.9 kJ mol −1 for the high and intermediate phases and E a (III) = 7.7 kJ mol −1 for the low temperature phase. These values are only a little higher than those for [Ni(NH 3 ) 6 ](NO 3 ) 2 (4.7 and 2.3 kJ mol −1 ) or for [Mg(NH 3 ) 6 ](NO

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Abstract  

The thermolysis of potassium hexa(carboxylato)ferrate(III) precursors, K3[Fe(L)6xH2O (L=formate, acetate, propionate, butyrate), has been carried out in flowing air atmosphere from ambient temperature to 900°C. Various physico-chemical techniques i.e. TG, DTG, DTA, XRD, IR, Mössbauer spectroscopy etc. have been employed to characterize the intermediates and end products. After dehydration, the anhydrous complexes undergo exothermic decomposition to yield various intermediates i.e. potassium carbonate/acetate/propionate/butyrate and α-Fe2O3. A subsequent decomposition of these intermediates leads to the formation of potassium ferrite (KFeO2) above 700°C. The same ferrite has also been prepared by the combustion method at a comparatively lower temperature (600°C) and in less time than that of conventional ceramic method.

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Abstract  

The thermal decomposition of lithium hexa(carboxylato)ferrate(III) precursors, (Li3[Fe(L)6xH2O, L = formate, acetate, propionate, butyrate), has been carried out in flowing air atmosphere from ambient temperature upto 500 °C. Various physico-chemical techniques, i.e., TG, DTG, DTA, XRD, SEM, IR, Mössbauer spectroscopy, etc., have been employed to characterize the intermediates and end products. After dehydration, the anhydrous complexes undergo decomposition to yield various intermediates, i.e., lithium oxalate/acetate/propionate/butyrate, ferrous oxalate/acetate and α-Fe2O3 in the temperature range of 185–240 °C. A subsequent decomposition of these intermediates leads to the formation of nanosized lithium ferrite (LiFeO2). Ferrites have been obtained at much lower temperature (255–310 °C) as compared to conventional ceramic method. The same nano-ferrite has also been prepared by the combustion method at a comparatively lower temperature (400 °C) and in less time than that of conventional ceramic method.

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Abstract  

Haem peroxidases are globular proteins with an iron-porphyrin complex as prosthetic group. They catalyze the oxidation of substrate by peroxides, frequently via free-radical intermediates. The catalytic cycle involves changes in the redox states of the prosthetic group, that can be monitored by changes in the intense absorption spectra. During the past decades, considerable scientific effort has been put into the elucidation of the mechanisms of reactions catalyzed by these enzymes. Radiation-chemical techniques have made an important contribution by providing information on the redox states of the enzymes and their interconversions, as well as on the properties of the free-radical intermediates involved.

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Abstract  

The authors continue their considerations concerning the validity of the steady-state approximation in non-isothermal kinetics. A sequence of two first-order consecutive reactions with an active intermediate was subjected to kinetic analysis by numerical solution of the corresponding differential kinetic equations for a number of particular cases. The results demonstrated that the rate of change of concentration of the active intermediate is negligibly small if the assumption made in the isothermal case is also accepted for the non-isothermal case, i.e. k 2(T(t))>> k 1(T(t)).

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