Thermodynamic Parameters of Nonisothermal Degradation of A New Family of Organometallic Dendrimer with Isoconversional Methods

The objective of this work is to obtain the thermodynamic parameters, namely, the changes of enthalpy, Gibbs free energy, and the entropy of two degradation steps observed in three of a new family of organometallic dendrimers. The isoconversional Flynn-Wall-Ozawa (FWO) model was employed to calculate the effective activation energy and pre-exponential factor. The changes of enthalpy and the entropy was consistent with the activation energy, whereas the change of Gibbs free energy remains positive during the entire degradation process, implying that the degradation is non-spontaneous and thus requires external heat supply.

MECHANODESTRUCTION OF ISOPRENE RUBBER. PART 3. KINETICS OF OXIDATIVE DESTRUCTION

Continuation of studies of changes in molecular parameters, in particular, the molecular weight (MM) during the plasticization (P) of SKI-3 isoprene rubber. The kinetics of oxidative destruction (OD) in the temperature range (T) 30-130 °C and time (t) 30–600 s were studied in detail. Plasticization of rubber, as before, was carried out in a laboratory rubber mixer of the company «NFM», and gel chromatographic studies were carried out on a gel chromatograph of the company «Waters». The speed constant OD K0 decreases in absolute value with a decrease in T and an increase in t. The calculated effective activation energy of OD Eeff decreases from 24,4 to 13 kJ/mol in the studied t range. The influence of the oxygen diffusion process on the kinetic features of the OD of SKI-3 at Р is pointed out.

New Approaches to Documenting Performance in the Museum: Value, History, and Strategy

This chapter shows how over the past two decades the relationship between the museum and performance has undergone a radical shift with the acquisition of performance-based artworks into the collection, shifting the role of the museum from that of a repository to that of a vital participant in the activation of the work. This chapter reflects on the new value this turn affords to documentation, and on how it is being used to support the effective activation of performance-based artworks in the museum. It reflects particularly on Tate’s development of documentation practices that address these new institutional needs and on how these navigate both immediate and potential future value.

Waste Tire Heat Treatment to Prepare Sulfur Self-Doped Char: Operando Insight into Activation Mechanisms Based on the Char Structures Evolution

Waste tire (WT) can be heat-treated to be high-quality sulfur self-doped char via pyrolysis and K2FeO4-assisted activation processes. This work aimed at further studying the activation mechanisms based on the char structures evolution by operando experimental method. Activation treatment process (from 50 °C to 800 °C and then held for 3 h) was divided into six typical stages (S1–S6) and consisted of carbonization process (S1–S4) and effective activation process (S4–S6). During the carbonization process, the specific capacitance only increased from 0.2 F/g to 12.4 F/g, aromatic ring systems and alkyl-aryl C-C bonds generated, S 2p3/2 (sulphide bridge) was mainly gradually consumed. During the effective activation process, the specific capacitance hugely increased from 12.4 F/g to 112.5 F/g, aromatic ring systems and alkyl-aryl C-C bonds turned to ordered graphitic char. The pores massively generated from S4 to S5, while micropores partly formed to larger and mesopores+macropores fractionally converting to smaller from S5 to S6. Besides, both S 2p3/2 and S 2p5/2 (sulphone bridge) were enriched after S5. Furthermore, the key structural parameters for huge improvement of specific capacitance were found and it further revealed that mesopores+macropores possessed stronger promotion effect than micropores and S 2p3/2 was more beneficial than S 2p5/2.

SYNTHESIS OF THALLIUM SULPHATE IN A SULFURIC ACID SOLUTION AT POLARIZATION BY CURRENT

Nowadays, the one of the actual problems is the recycling of metal waste and its provision to consumers. However, it is known that there are a number of difficulties with the recycling of thallium waste. By using new recycling methods, it's possible to increase thallium resources and lower prices for thallium-derived products. Therefore, some work was carried out to extract its compounds from thallium waste by studying the electrochemical properties of thallium in our research work. The experimental results showed that thallium electrodes dissolve in an aqueous solution of sulfuric acid under alternating current polarization with the formation of thallium (I) sulfate. In this work, the kinetics of electrochemical oxidation-reduction of thallium in aqueous solutions of sulfuric acid is studied by potentiometry. To characterize the mechanism of thallium electrooxidation, the following parameters were calculated: the order of the reaction and the effective activation energy of the process. The impact of electrolysis modes: current density, concentration and temperature of the electrolyte on the dimensional charac-teristics of the obtained thallium (I) sulfate was investigated.

Separated Redox Sites Strategies for Engineering High-Efficient Photocatalysts: Pagoda-Like In2O3/CuO Heteroepitaxial Structure Coated by N Doped C Layer

In order to prepare efficient photocatalysts, it is necessary to consider not only the generation, separation and migration of photo-generated carriers, but also the effective activation of reactants and the...