Comparison of Thermal Transformation Processes of Six Mullite Precursors

2021 ◽  
pp. 367-415
Author(s):  
Akshoy Kumar Chakraborty
Keyword(s):  
Thermal Transformation ◽  
Transformation Processes

Reaction Time 1H NMR Studies of Thermal Transformation Processes of Fossil Fuels

1984 ◽  
pp. 617-628
Author(s):  
L. J. Lynch ◽  
D. S. Webster ◽  
N. A. Bacon ◽  
W. A. Barton
Keyword(s):  
Reaction Time ◽  
1H Nmr ◽  
Fossil Fuels ◽  
Thermal Transformation ◽  
Nmr Studies ◽  
Transformation Processes

scholarly journals Thermal Stability and Decomposition Products of P-Doped Ferrihydrite

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4113
Author(s):  
Gabriela Pieczara ◽  
Maciej Manecki ◽  
Grzegorz Rzepa ◽  
Olaf Borkiewicz ◽  
Adam Gaweł
Keyword(s):  
Thermal Stability ◽  
Room Temperature ◽  
Thermal Transformation ◽  
X Ray Diffraction ◽  
Decomposition Products ◽  
X Ray ◽  
Molar Ratios ◽  
P Content ◽  
Heating Up ◽  
Transformation Processes

This work aimed to determine the effect of various amounts of P admixtures in synthetic ferrihydrite on its thermal stability, transformation processes, and the properties of the products, at a broad range of temperatures up to 1000 °C. A detailed study was conducted using a series of synthetic ferrihydrites Fe5HO8·4H2O doped with phosphates at P/Fe molar ratios of 0.2, 0.5, and 1.0. Ferrihydrite was synthesized by a reaction of Fe2(SO4)3 with 1 M KOH at room temperature in the presence of K2HPO4 at pH 8.2. The products of the synthesis and the products of heating were characterized at various stages of transformation by using differential thermal analysis accompanied with X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy-energy dispersive X-ray spectroscopy. Coprecipitation of P with ferrihydrite results in the formation of P-doped 2-line ferrihydrite. A high P content reduces crystallinity. Phosphate significantly inhibits the thermal transformation processes. The temperature of thermal transformation increases from below 550 to 710–750 °C. Formation of intermediate maghemite and Fe-phosphates, is observed. The product of heating up to 1000 °C contains hematite associated with rodolicoite FePO4 and grattarolaite Fe3PO7. Higher P content greatly increases the thermal stability and transformation temperature of rodolicoite as well.

scholarly journals Cytotoxic Pt(IV) and Ru(II) complexes containing a biologically relevant edda-type ligand: A comparative study of their thermal properties

2016 ◽  
Vol 81 (8) ◽  
pp. 897-905
Author(s):  
Ljiljana Mihajlovic-Lalic ◽  
Ljiljana Damjanovic ◽  
Maja Sumar-Ristovic ◽  
Aleksandar Savic ◽  
Tibor Sabo ◽  
...  
Keyword(s):  
Activation Energy ◽  
Thermal Transformation ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Biologically Relevant ◽  
Dominant Process ◽  
Three Stages ◽  
The Mean ◽  
Final Residue ◽  
Transformation Processes

The thermal behaviour of a Pt(IV) and a Ru(II) complex coordinated to O,O'-di-n-butyl-(S,S)-ethylenediamine-N,N'-di-2-(3-cyclohexyl)propanoate has been investigated using thermogravimetry (TG) and differential scanning calorimetry (DSC). The study included investigation of the thermal decomposition of these complexes in the temperature range of 30 to 590?C and evaluation of activation energy for the first decomposition steps. For both metal complexes, broad DSC peaks indicated complex thermal transformation processes. The two-step decomposition of the Pt(IV) complex started at 175 and ended at about 418?C, leaving elemental platinum as a final residue. On the other hand, the Ru(II) analogue decomposed in three stages. Thermal degradation was evident beginning at 144?C and suggested the decomposition of a coordinated ligand as dominant process. For this complex, the proposed final residue was RuO2. Kinetic parameters for the first decomposition step were obtained by means of multi-heating rates method, in this case the Kissinger-Akahira-Sunose (KAS) method. The mean activation energy calculated for 0.2 < ? < 0.8 were 122.0 kJ mol?1 for the Pt(IV) and 118.9 kJ mol?1 for the Ru(II) complex and decreased constantly, characteristic of a multi-step process.

THE IMPACT OF UKRAINE'S EXCISE DUTY POLICY ON THE TRANSFORMATION PROCESSES OF THE TOBACCO MARKET

2020 ◽  
Vol 2020 (10) ◽  
pp. 19-33
Author(s):  
Nadiia NOVYTSKA ◽  
◽  
Inna KHLIEBNIKOVA ◽  
Keyword(s):  
Structural Changes ◽  
Tax Avoidance ◽  
Transformation Process ◽  
State Regulation ◽  
Tobacco Products ◽  
Excise Duty ◽  
Increasing Demand ◽  
High Level ◽  
The Impact ◽  
Transformation Processes

The market of tobacco products in Ukraine is one of the most dynamic and competitive. It develops under the influence of certain factors that cause structural changes, therefore, the aim of the article is to conduct a comprehensive analysis of transformation processes in the market of tobacco and their alternatives in Ukraine and identify the factors that cause them. The high level of tax burden and the proliferation of alternative products with a potentially lower risk to human health, including heating tobacco products and e-cigarettes, are key factors in the market’s transformation process. Their presence leads to an increase in illicit turnover of tobacco products, which accounts for 6.37% of the market, and the gradual replacement of cigarettes with alternative products, which account for 12.95%. The presence on the market of products that are not taxed or taxed at lower rates is one of the reasons for the reduction of excise duty revenues. According to the results of 2019, the planned indicators of revenues were not met by 23.5%. Other reasons for non-fulfillment of excise duty revenues include: declining dynamics of the tobacco products market; reduction in the number of smokers; reorientation of «cheap whites» cigarette flows from Ukraine to neighboring countries; tax avoidance. Prospects for further research are identified, namely the need to develop measures for state regulation and optimization of excise duty taxation of tobacco products and their alternatives, taking into account the risks to public health and increasing demand of illegal products.

TLC/HPTLC and HPLC methods for monitoring microbial transformation processes

2004 ◽  
Vol 17 (2) ◽  
pp. 132-136 ◽  
Author(s):  
Balázs Erdélyi ◽  
Antal Szabó ◽  
László Birincsik ◽  
Gábor Seres ◽  
János Salát ◽  
...  
Keyword(s):  
Microbial Transformation ◽  
Transformation Processes

Global recession risks and challenges to economic regulation

2020 ◽  
pp. 37-46
Author(s):  
E. Smirnov
Keyword(s):  
World Economy ◽  
Modern World ◽  
Economic Regulation ◽  
Present Stage ◽  
Global Inequality ◽  
Global Recession ◽  
Stage Of Development ◽  
Economic Balance ◽  
Key Aspects ◽  
Transformation Processes

At the present stage, the world economy is experiencing a difficult stage of development, which is determined by many factors, in particular, the dynamics of economic growth, the increase in global inequality, and the mixed influence of digital transformation processes. The article analyzed the main trends and risks of modern world economy development, as well as identified key aspects of multilateral regulation and restoration of economic balance on the international scale.

Assessing the Quality of Management of Transformation Processes in Economic Systems

2020 ◽  
Vol 26 (9) ◽  
pp. 952-956
Author(s):  
M. V. Malyshkina ◽  
M. V. Miroslavskaya
Keyword(s):  
Systems Approach ◽  
Mutual Influence ◽  
Organizational Transformation ◽  
Quality Criterion ◽  
Economic Transformation ◽  
Economic Systems ◽  
Negative Consequences ◽  
Management Actions ◽  
Transformation Processes

Aim. The presented study aims to develop the methodology for assessing the quality of management of organizational transformation processes. Tasks. To achieve the set aim, the authors solve the following problems: determine the essence and content of socio-economic transformation, formulate quality assurance principles for the management of transformation processes, draw attention to the problem of selecting a unified quality criterion for the management of organizational transformation processes. Methods. This study uses general scientific methods of cognition, including analysis and synthesis. It also applies a systems approach to identify the major problems of assessing the quality of management of transformation processes, including the problem of selecting a unified quality criterion for the management of transformation processes and formulating the principles of ensuring the quality of management of transformation processes. Results. The global problem of managing transformation processes in the economic system consists in the complexity of the managed processes, which increases due to the multidimensionality, mutual influence, and the resulting uncertainty of interactions between the elements of the system. It is concluded that the methodology for assessing the quality of management of transformation processes is based on the principle of integrating separate measures to improve the quality of management of system elements into a single system of management actions and the principle of ensuring that management actions are primarily aimed at preventing possible negative consequences of the transformation of economic systems, i.e. reducing the potential impact of unfavorable events and their consequences. To assess the effectiveness of targeted management actions and productive actions aimed at organizing, controlling, and guiding the transformation process, the authors actualize the problem of selecting an adequate quality criterion for the management of transformation processes in economic systems and put forward a hypothesis about a possible unified criterion of management quality. Conclusions. The principle of integrating separate measures to improve the quality of management of system elements and the principle of ensuring that management actions are aimed at preventing possible negative consequences lie at the core of the methodology for assessing the quality of management of transformation processes in economic systems. The quality assessment methodology should be developed in the direction of finding a unified quality criterion for managing transformation processes in economic systems.

Biodegradability of Danube bank filtrate and its enhancement by ozonation

2007 ◽  
Vol 7 (3) ◽  
pp. 139-144
Author(s):  
V.Z. Cukic ◽  
V.L. Knezic
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Distribution Networks ◽  
Organic Content ◽  
Low Risk ◽  
Danube River ◽  
Source Water ◽  
Transformation Processes ◽  
By Products

The reduction of organic content through transformation processes in the Danube aquifer along a studied area, biodegradability of Danube bank filtrate and its enhancement by ozonation have all been examined in a study carried out in order to assess amenability of Danube bank filtrate for bio-filtration. As determined during the study period Dissolved Organic Carbon (DOC) varied from 4.6–6.5 mgC/L and from 2.8–3.7 mgC/L in Danube River and Danube bank filtrate respectively. As determined 11.2% of Danube bank filtrate DOC was bio-degradable. A substantial enhancement of biodegradability has been observed after the application of Ozone dosages ranging from 0.45 to 0.9 mgO3/ mgC. It was concluded that Danube bank filtrate itself is not amenable for bio-filtration but an enhancement of its bio-degradability by ozonation could make bio-filtration a reasonable and economical option for reducing of DOC content to the levels that provide low risk of excessive disinfection by-products formation and prevent bacterial re-growth in distribution networks of cities using Danube bank filtrate as the source water.

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