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International Journal of Thermodynamics and Chemical Kinetics

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International Journal of Thermodynamics and Chemical Kinetics International Journal of Thermodynamics and Chemical Kinetics welcomes research papers and review articles concerning the development in the field of thermodynamics and chemical kinetics. Maximum entropy thermodynamics, non-equilibrium thermodynamics, reaction's mechanism, gas phase kinetics and solution kinetics are a few topics that are included in the journal.

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Atmospheric thermodynamics

! Biological thermodynamics ! Chemical thermodynamics ! Equilibrium thermodynamics ! Maximum entropy thermodynamics ! Non-equilibrium thermodynamics ! Maximum entropy thermodynamics ! Non-equilibrium thermodynamics ! Reaction's mechanism ! Gas phase kinetics ! Solution kinetics

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Priyanka Garg

Akanksha Marwah

Chhavi Goel

Deepika Bhadauria

Shrawani Verma

EDITORIAL BOARD MEMBERS Dr. Chang-Yu Sun State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing, China

Dr. Rekha Lagarkha Asst. Prof. Department of Chemistry Bundelkhand University India

Prof. Karipeddi Ramakrishna Department of Chemistry, GIS GITAM University, Visakhapatnam, India

Dr. Vidyavati A. Shastry Professor and Head, Department of Chemistry SEA College of Engineering and Technology, K. R. Puram Bangalore, India

Dr. Yee-Wen Yen Professor/Vice Dean of College of Engineering Department of Materials Science and Engineering National Taiwan University of Science and Technology, Taiwan

Dr. Bharat Modhera Department of Chemical Engineering, Maulana Azad National Institute of Technology, Bhopal, India

Dr. Rose Philo Department of Chemistry, St.Paul's College, Kalamassery, Kochi, Kerala, India

Dr. Rajneesh Dutt Kaushik Department of Chemistry, Gurukul Kangri University, Haridwar (Uttarakhand), India

Dr. Sushil Kumar Chemical Engineering Department, Motilal Nehru National Institute of Technology (MNNIT), Allahabad, U. P., India

Dr. Niki Sweta Jha National Institute of Technology (NIT) Patna, Bihar, India

Dr. Ajaya Kumar Singh Department of Chemistry (DST-FIST Sponsored) Govt. V. Y. T. PG. Autonomous College, Chhattisgarh, India

Dr. Vidyavathi A. Shastry Department of Chemistry, SEA College of Engineering & Technology, K. R. Puram, Bangalore, India

Dr. Sandeep Rai Department of Chemistry/Polymer and Rubber, Shroff S.R. Rotary Institute of Chemical Technology, Vataria, Ankleshwar, India

Dr. Kishore Dasari Navin Fluorine International Limited, India

Dr. Lubna Najam Science Academy Coaching Centre, Mumbai

Ramakrishna Rao Department of Chemistry, GITAM School of Technology, GITAM University, Bangalore, Karnataka, India

Dr. Rajesh Kumar Sahu Department of Chemistry, Vishwavidyalaya Engineering College, Lakhanpur Sarguja University Ambikapur, Chattisgarh, India

Shaista Ali Department of Chemistry, GC University, Lahore, Punjab, India

EDITORIAL BOARD MEMBERS Ranganathan Subramanian Department of Chemistry, Indian Institute of Technology, Patna, Bihar, India

Dr. Annapurna Nowduri Department of Engineering Chemistry, A. U. College of Engineering (Autonomous), Andhra University,Visakhapatnam, Andhra Pradesh, India

Dr. Vajjiravel Murugesan Department of Chemistry, B. S. Abdur Rahman University, Chennai, Tamil Nadu, India

Dr. G Vijaya Lakshmi Department of Chemistry, University College of Technology, Osmania University, Hyderabad, Andhra Pradesh, India

Dr. A. K. Sood Department of Chemistry, Guru Nanak Dev University, Amritsar, Punjab, India

Dr. Suranani Srinath Department of Chemical Engineering, National Institute of Technology, Warangal, Andhra Pradesh, India

From the Editor's Desk Dear Readers, We would like to present, with great pleasure, the inaugural volume of a new scholarly journal, International Journal of Thermodynamics and Chemical Kinetics. This journal is part of the Applied Sciences, and is devoted to the scope of present Thermodynamics and Chemical Kinetics issues, from theoretical aspects to application-dependent studies and the validation of emerging technologies. This new journal was planned and established to represent the growing needs of Thermodynamics and Chemical Kinetics as an emerging and increasingly vital field, now widely recognized as an integral part of scientific and technical investigations. Its mission is to become a voice of Thermodynamics and Chemical Kinetics, addressing researchers and practitioners in this area. The core vision of International Journal of Thermodynamics and Chemical Kinetics in JournalsPub is to propagate novel awareness and know-how for the profit of mankind ranging from the academic and professional research societies to industry practitioners in a range of topics in Thermodynamics and Chemical Kinetics in general. JournalsPub acts as a pathfinder for the scientific community to publish their papers at excellently, well-timed & successfully. International Journal of Thermodynamics and Chemical Kinetics focuses on original high-quality research in the realm of Atmospheric, Biological & Chemical thermodynamics, Equilibrium thermodynamics, Reaction's mechanism, Gas phase kinetics, Solution kinetics etc. The Journal is intended as a forum for practitioners and researchers to share the techniques of Thermodynamics and Chemical Kinetics and solutions in the area. Many scientists and researchers have contributed to the creation and the success of Thermodynamics and Chemical Kinetics. We are very thankful to everybody within that community who supported the idea of creating an innovative platform. We are certain that this issue will be followed by many others, reporting new developments in the field of Thermodynamics and Chemical Kinetics. This issue would not have been possible without the great support of the Editorial Board members, and we would like to express our sincere thanks to all of them. We would also like to express our gratitude to the editorial staff of JournalsPub, who supported us at every stage of the project. It is our hope that this fine collection of articles will be a valuable resource for Thermodynamics and Chemical Kinetics readers and will stimulate further research into the vibrant area of Thermodynamics and Chemical Kinetics. Puneet Mehrotra Managing Director

Contents 1. Studies on the Kinetics of Thermal Decomposition of Copper Oxalate Mixed With Silver Oxalate K. Sarada, K. Muraleedharan

2. Kinetics and Mechanism of Ruthenium(III) Catalysed Oxidation of L-Arginine by Periodate in Alkaline Medium Garapati Sridevi, Nowduri Annapurna, Parvataneni Vani

3. Thermal Decomposition Kinetics of Mefenamic Acid Crystals S. Ramukutty, E. Ramachandran

4. Kinetics vs. Thermodynamics: An Overview Vishal Jain

5. Graphene Modification for Thermal Modulators: A Current Report Sona Chahal

International Journal of Thermodynamics and Chemical Kinetics Vol. 2: Issue 1

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Studies on the Kinetics of Thermal Decomposition of Copper Oxalate Mixed With Silver Oxalate K. Sarada, K. Muraleedharan* Department of Chemistry, University of Calicut, Calicut, India

Abstract The coprecipitates, Ag2Cu(C2O4)nH2O of varying composition [Ag = (1 and 2)%], have been synthesized and were characterized by means of IR, XRD, and SEM. The decomposition of the prepared oxalates was monitored by differential scanning calorimetry (DSC) and thermogravimetry (TG). The DSC studies reveal that the decompositions of the mixed oxalates were all complex exothermic processes with resemblance to the exothermic reaction of copper oxalate and ranges from 540 to 600 K. The decomposition kinetics was studied by thermogravimetry at four different heating rates: 5, 10, 15, and 20 K/min. The TG data were subjected to linear least squares analyses (in the range α = 0.1–0.9) using the isoconversional methods of KAS, FWO, Vyazovkin, and Tang to find the values of activation energy (Eα). The activation energies of the pure copper oxalate, in N2 atmosphere, obtained by the above-mentioned methods are 192.1, 191.3, 191.9, and 192.3 kJ/mo1 and that of pure silver oxalate are 179.5, 187.4, 187.9, and 179.9 kJ/mo1, respectively. Copper oxalate coprecipitated with 1% silver oxalate gave activation energy values 206.4, 215.8, 216.6, and 206.9 kJ/mo1 and the coprecipitated with 2% silver oxalate gave activation energy values 182.8, 192.3, 193.1, and 183.3 kJ/mo1. The kinetic analysis of copper–silver oxalates prepared shows a decrease in average activation energy with increase in the concentration of silver oxalate. The variation of activation energy during thermal decomposition reflects the changing mechanism during the course of the reaction. It is observed that the activation energy of copper oxalate is decreased from its original value by the addition of 2% Ag2C2O4. Hence, it will be interesting to study further about the effect of addition of Ag2C2O4 higher than 2%. Keywords: decomposition kinetics, differential scanning calorimetry, isoconversional methods, thermogravimetry

INTRODUCTION Thermal decomposition of metal oxalates is an important field of solid state chemistry.[1–6] Transition metal oxalates act as precursors for the synthesis of oxide nanoparticles that are involved in several industrial and analytical applications.[1] High purity transition metal oxalates can be made by co-precipitation techniques, in which the metal ions are simultaneously precipitated in the expected stoichiometric proportions and provide the possibility of controlling the physical and chemical

properties of the final products. Most of the single phase solid solution precipitates assuring homogeneity. Though there is a chance of segregation during precipitation, the degree of mixing is far superior to that obtained with conventional mixing techniques. Oxalates form solid solutions which can be easily decomposed. The decomposition kinetics of many oxalates

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International Journal of Thermodynamics and Chemical Kinetics Vol. 2: Issue 1

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Kinetics and Mechanism of Ruthenium(III) Catalysed Oxidation of L-Arginine by Periodate in Alkaline Medium Garapati Sridevi1, Nowduri Annapurna2, Parvataneni Vani3* 1

AU College of Engineering for Women, Andhra University, Visakhapatnam, AP, India Department of Engineering Chemistry, AU College of Engineering (A), Andhra University, Visakhapatnam, AP, India 3 Department of Inorganic and Analytical Chemistry, Andhra University, Visakhapatnam, AP, India

Abstract The kinetics of the ruthenium(III) catalysed oxidation of L-arginine by periodate was studied spectrophotometrically in alkaline medium at 280 nm and at a temperature 35 ± 0.1°C. It was found that the reaction is first order with respect to [catalyst] and [periodate]. The reaction showed fractional order dependence on [substrate] and [alkali]. The oxidation product of the reaction was found to be aldehyde. The anionic species of arginine (Arg) is considered to be the reactive species. A suitable mechanism involving complexation between Arg and [Ru(VIII)] was proposed leading to the rate law. k K K2 [ Arg] [ RuIII ] [ OH - ] 1 d [periodate] t t ____________________________ Rate = -___________ = dt 1 + K2[ Arg] t + K1[OH ] + K1 K 2 [ Arg] [OH- ] t

The activation parameters of the rate determining step Ea, and ∆S#, were computed to be 57.3 ± 1.9kJ mol1 and -196.5 ± 5.8 JK1mol1 respectively. Keywords: oxidation of L-arginine, periodate, ruthenium (III)

INTRODUCTION Arginine is one of the essential amino acid and is an important constituent of proteins. Since it is an essential amino acid it cannot be synthesized by human body.

stable oxidation state for ruthenium. The mechanism of the catalysis is quite complicated due to the formation of different intermediate complexes, free radicals and different oxidation states of ruthenium.

The kinetics and mechanism of oxidation of arginine were studied previously using various oxidants.[1–15] In continuation of our studies on the oxidation of arginine,[16,17] we now report the mechanism of its oxidation in alkaline medium by periodate in presence of ruthenium(III).

The uncatalysed oxidation of arginine by alkaline periodate [17] was studied at 323K. Since there is no direct reaction between arginine and periodate at 308K and since ruthenium(III) was found to catalyse the reaction considerably, we have under taken a detailed kinetic and mechanistic study of the title reaction in 0.4 mol dm  3 alkaline medium.

Ruthenium(III) acts as a catalyst in several redox reactions in alkaline solution. The trivalent state is the most

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International Journal of Thermodynamics and Chemical Kinetics Vol. 2: Issue 1

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Thermal Decomposition Kinetics of Mefenamic Acid Crystals S. Ramukutty, E. Ramachandran* Department of Physics, Thiruvalluvar College, Papanasam, India

Abstract Single crystals of mefenamic acid were crystallized by gel growth method for the first time in literature. Crystal structure was confirmed using single crystal X-ray diffraction analysis. Kinetic analysis was made from the isothermal thermogravimetric analysis/differential thermal analysis (TGA/DTA) data using Coats–Redfern (CR) relation. Thermodynamic parameters were also determined. Arrhenius equation for mefenamic acid is k = 0.28 × 109 e–116551/RT mol–1s–1. Keywords: kinetic analysis, mefenamic acid, thermal analysis

INTRODUCTION Kinetic analyses were carried out in growth as well as decomposition of crystalline materials. Among this thermal analysis during thermal decomposition is useful for the determination of rate of chemical reaction, decomposition products and thermodynamic parameters. In pharmaceutics problems like the purity level, qualitative and quantitative analysis of drug formulations and polymorphism are resolved using thermal analysis.[1,2] Moreover, the shelf life period of the drugs may be estimated by the kinetic parameters. Further solid state kinetics studies are helpful in the calculation of the parameters of Arrhenius equation and to determine the mechanism of decomposition reaction. Mefenamic acid [2-(2,3dimethylphenyl)aminobenzoic acid] is a non-steroidal anti-inflammatory drug (NSAID). It is used to decrease pain and blood loss from menstrual periods. Thermal analysis of pure mefenamic acid was less reported. Thermal analyses of few NSAIDs are reported by the authors.[3–6] Presently, single crystals of mefenamic acid were crystallized by gel growth

method. The crystal structure of the grown crystal was confirmed using single crystal X-ray diffraction method. Thermal analysis was carried out using isothermal thermal decomposition. Coats–Redfern relation was applied on the thermal decomposition data to evaluate the kinetic parameters from the thermal analysis. EXPERIMENTAL Mefenamic acid was purchased from Blue cross laboratories Ltd., Goa, India. Organic solvents were purchased from Spectrum Chemical Reagents, Cochin. Test tubes were used as crystal growth vessels. Crystal growth by reduction of solubility was employed for the crystallization. An aqueous solution of sodium metasilicate (Na2SiO35H2O) of specific gravity 1.06 gm/cm3 was prepared and the pH of the solution was adjusted using 5 M acetic acid. 5% w/v of mefenamic acid in methanol solution was placed over the set gel taken in the test tube. Transparent, long rod shaped crystals

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International Journal of Thermodynamics and Chemical Kinetics Vol. 2: Issue 1

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Kinetics vs. Thermodynamics: An Overview Vishal Jain MM College, Modinagar, Uttar Pradesh, India

Abstract Almost every chemical reaction has a kinetic and a thermodynamic aspect. The terms ‘kinetic’ and ‘thermodynamic’ though inter-related are two different facets of a chemical reaction. Here is an overview of the underlying relationships between the two through application to chemical reactions and an example from natural processes. Keywords: activation energy, chemical reaction, kinetic, reactant, thermodynamics

Introduction Chemical reactions are described as those processes in which a set of molecules or chemicals referred as ‘reactants’ are changed into another set of new molecules or chemicals called the ‘products’. Kinetics and thermodynamics are two inter-related yet different and important aspects of such chemical reactions. Kinetic study gives us the information about how fast a reaction will run while thermodynamic analysis answers the question of whether a reaction is thermodynamically favorable or not. Kinetics Overview Kinetic studies tell us how fast or slow a reaction can occur. In other words, it helps in determining the rate of a chemical reaction. The quantity related to kinetics is

the rate constant ‘k’. This rate constant is associated with the activation energy required by the reactants to proceed the reaction in forward direction. The rate constant thus, measures how fast the reaction reaches the equilibrium assuming the reactants have sufficient activation energy that pulls the reaction in forward direction, i.e., from reactants to formation of products.[1] The rate of reaction, the rate constant, and the kinetic energy required for activation of reaction together indicates how fast the reaction reaches equilibrium. The value of ‘k’ can be increased in the presence of a catalyst such as an enzyme. This increases the rate of reaction. The catalyst does this in two ways: first by increasing the energy of reactants and second by lowering the transition state energy, shown in Figure 1.

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International Journal of Thermodynamics and Chemical Kinetics Vol. 2: Issue 1

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Graphene Modification for Thermal Modulators: A Current Report Sona Chahal* Department of Electrical and Electronics, Lord Krishna College of Engineering, Ghaziabad, Uttar Pradesh, India

Graphene has attracted a lot of interest in recent years on account of its unique electrical and optical properties. Graphene has a spring constant in the range of 15N/m and a Young's modulus of 0.5 Tpa, which shows that it has a breaking strength 200 times greater than steel and one of the strongest materials known. Moreover, the electronic structure of graphene is unique in the sense that it can absorb a significant part of incident white light. From the point of view of thermal properties, graphene exhibits strong heat conductivity which can be improved further by embedding multiple layers of graphene into silicon chips. While designing electronic components, generation of excess heat creates big problem. Getting rid of the heat generated is quite cumbersome. In a recent report, researchers at Agency for Science, Technology and Research (A*STAR), Singapore, have found an alternative by which the heat generated in graphene can be modified and utilized in a more efficient way. Graphene is a carbon form consisting of planar sheets which are one atom thick, with the atoms arranged in a honeycombshaped lattice, and has an extraordinarily high thermal conductivity. Researchers from the A*STAR Institute of High Performance Computing have developed a way to reduce graphene's thermal conductivity, allowing excess heat to be dissipated or utilized for generation of electricity.

The team demonstrated that clamping a graphene sheet between two other graphene sheets under moderate pressure will decrease the thermal conductivity by approximately one-third. Adding more clamps and adjusting the pressure allow the heat-flow to be tuned, fashioning a 'thermal modulator', that is similar to electrical components such as variable resistors that control the flow of electricity. The design is based on molecular dynamics to simulate the movement of phonons which are the thermal equivalent of electromagnetism's photons. The clamping does not cause any sort of permanent damage to graphene. The thermal properties of graphene can be further modified by doping or introducing some sort of defects in its structure that will cause permanent change in the material. The A*STAR team's approach, however, provides a considerable advantage, i.e., "It does not change the crystal structure and is fully reversible-if the pressure is removed, the graphene returns to its pristine state". It was observed that the boundaries of the clamped area had the largest energy level shift and showed maximum scattering. The effect was less significant in center of the clamps. The team then made efforts to create more boundaries and so changed the simulation from a single clamped area to multiple smaller areas. It was found that the thermal conductivity dropped dramatically.

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¬ ¬ International Journal of Industrial Engineering

Manufacturing International Journal of Mechanical Dynamics and Analysis International Journal of Fracture and damage Mechanics International Journal of Structural Mechanics and Finite Elements

and Design ¬ International Journal of Manufacturing and

Materials Processing ¬ International Journal of Mechanical Handling and

Automation 5 more...

Electronics and Telecommunication « International Journal of Radio Frequency Design « International Journal of VLSI Design and Technology « International Journal of Embedded Systems and Emerging

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Chemical Engineering « International Journal of Renewable Energy and its

Planning Planning « International Journal of Rural and Regional Planning

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« International Journal of Town Planning and Management

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Nursing

Material Sciences and Engineering

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Biotechnology « International Journal of Industrial Biotechnology and « « « «

Jan – Jun 2016

Civil Engineering

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Commercialization « International Journal of Environmental Chemistry « International Journal of Agrochemistry « International Journal of Prevention and Control of Industrial Pollution 1 more...

Architecture « International Journal of Housing and Human Settlement

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International Journal of Thermodynamics & Chemical Kinetics

Nanotechnology « International Journal of Applied Nanotechnology « International Journal of Nanomaterials and Nanostructures « International Journals of Nanobiotechnology

Chemistry

Physics « International Journal of Solid State Materials « International Journal of Optical Sciences