Serhat VARIS | Middle East Technical University (original) (raw)

Papers by Serhat VARIS

Research paper thumbnail of A Review of Polycyclic Aromatic Energetic Materials

Http Dx Doi Org 10 1080 10406630903135971, Jul 22, 2009

Explosives are employed extensively not only in military areas but also in civilian applications.... more Explosives are employed extensively not only in military areas but also in civilian applications. There are many researchers working on the discovery of explosives. In recent years, synthetic and theoretical studies on polycyclic aromatic explosives have received significant interest. The present short review concentrates on the synthesis and some of the physico-chemical characteristics of energetic materials of the classes of tetraazapentalene, naphthalene, di-and tetraaza-naphthalene, pyrazolo-pyrazole, benzofuroxan, tetrazine and tetrazene derivatives as well as theoretical studies. A brief comment is also made on the emerging explosive concepts such as velocity of detonation, detonation pressure etc. The compounds in the review have the potential for subsequent applications in the area of energetic materials. Therefore, an endeavor is made to assemble the important contributions made by the various scientists in the area of energetic materials in this review.

Research paper thumbnail of Desensitization of TNAZ via Molecular Structure Modification and Explosive Properties - A DFT Study

Acta Chimica Slovenica, Dec 1, 2012

TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with... more TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with greater performance when compared to melt castable explosive, TNT (trinitrotoluene). Desensitization of explosives is a significant area in military use. One current method is to use additives and coatings for explosives, as in the case of RDX. Another tactic would be to attempt small molecular level chemical changes in the explosive that bring the expected decrease in sensitivity without noteworthy loss in performance. TNAZ has three nitro groups. We thought that conversion of the nitro groups to nitroso and amine groups may decrease the sensitivity. We have correlated the bond dissociation energies with sensitivity and h50 values obtained from Keshavarz relations. We have also investigated chemical hardness and Mulliken electronegativities employing the frontier molecular orbitals. Furthermore, the explosive properties, i.e. detonation velocity (D), and detonation pressure (P) have been questioned by using both Kamlet-Jacobs equations and Keshavarz relations. Detonation products and power index values have also been calculated. We have proved that molecular modification is an operative method in desensitization of TNAZ.

Research paper thumbnail of Molecular Modelling of Some Explosives and Propellants

iv I hereby declare that all information in this document has been obtained and presented in acco... more iv I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last name : Serhat VARIŞ Signature : v ABSTRACT MOLECULAR MODELLING OF SOME EXPLOSIVES AND PROPELLANTS VARIŞ, Serhat

Research paper thumbnail of On the Possibility of Autoxidation of TEX - A DFT Study

Propellants, Explosives, Pyrotechnics, 2014

Research paper thumbnail of Desensitization of TNAZ via Molecular Structure Modification and Explosive Properties - A DFT Study

Acta chimica Slovenica, 2012

TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with... more TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with greater performance when compared to melt castable explosive, TNT (trinitrotoluene). Desensitization of explosives is a significant area in military use. One current method is to use additives and coatings for explosives, as in the case of RDX. Another tactic would be to attempt small molecular level chemical changes in the explosive that bring the expected decrease in sensitivity without noteworthy loss in performance. TNAZ has three nitro groups. We thought that conversion of the nitro groups to nitroso and amine groups may decrease the sensitivity. We have correlated the bond dissociation energies with sensitivity and h50 values obtained from Keshavarz relations. We have also investigated chemical hardness and Mulliken electronegativities employing the frontier molecular orbitals. Furthermore, the explosive properties, i.e. detonation velocity (D), and detonation pressure (P) have be...

Research paper thumbnail of Synthesis and characterization of a new soluble conducting polymer and its electrochromic device

Solid State Sciences, 2006

Research paper thumbnail of Synthesis and characterization of a new soluble conducting polymer and its electrochromic device

Solid State Sciences, 2006

Research paper thumbnail of A soluble conducting polymer of 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole and its electrochromic device

Thin Solid Films, 2007

A monomer 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole was synthesized via reaction of 1,4-di(2-thi... more A monomer 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole was synthesized via reaction of 1,4-di(2-thienyl)-1,4-butanedione and p-toluidine in the presence of catalytical amount of p-toluenesulfonic acid. Chemical polymerization of the monomer yielded a soluble polymer. The average molecular weight was determined by gel permeation chromatography as number average molecular weight (Mn) 2.5×103 g/mol. The monomer was also electrochemically polymerized in the presence of LiClO4, NaClO4 (1:1) as the supporting electrolyte in acetonitrile. Cyclic Voltammetry, Fourier Transform Infra Red, Nuclear Magnetic Resonance, Scanning Electron Microscopy and Ultraviolet–Visible Spectroscopy were employed for the characterization of the polymer. Spectroelectrochemistry analysis of homopolymer revealed an electronic transition at 428 nm which corresponds to π–π⁎ transition. Switching ability of the homopolymer was evaluated by kinetic studies upon measuring the percent transmittance (%T) at the maximum contrast point, indicating that poly(2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole) is a suitable material for electrochromic devices.

Research paper thumbnail of Interaction of an α-Particle with TATB

Zeitschrift für anorganische und allgemeine Chemie, 2014

Interaction of an alpha particle with triaminotrinitrobenzene (TATB) which is an insensitive expl... more Interaction of an alpha particle with triaminotrinitrobenzene (TATB) which is an insensitive explosive has been investigated by density functional calculations. It has been found that α-particles interact with TATB disturbing its planar geometry. As a result, the C-NO 2

Research paper thumbnail of A Possible Complex between TNT and Epinephrine - A DFT Study

Zeitschrift für anorganische und allgemeine Chemie, 2014

The interaction between TNT and a vitally significant biological molecule, epinephrine, was inves... more The interaction between TNT and a vitally significant biological molecule, epinephrine, was investigated at the level of density functional theory. Two models are constructed; (i) an intimate pair of TNT and epinephrine and (ii) a π complex of them. The calculations (in vacuo conditions) have showed that these molecules in the intimate

Research paper thumbnail of Nitro Derivatives of Parabanic Acid as Potential Explosives: A Theoretical Study

Zeitschrift für anorganische und allgemeine Chemie, 2014

This work deals with certain parabanic acid (PA) derivatives because they possess great calculate... more This work deals with certain parabanic acid (PA) derivatives because they possess great calculated density (Ͼ1.8 g·cm -3 ) and high content of nitrogen (26 %). Computed ballistic properties of eight different parabanic acid derivatives are presented. The structures were optimized at the B3LYP/6-31G

Research paper thumbnail of Effects of Epoxidation and Nitration on Ballistic Properties of FOX-7 - A DFT Study

Zeitschrift für anorganische und allgemeine Chemie, 2013

1,1-Diamino-2,2-dinitroethylene (FOX-7) has received increasing attention since it was industrial... more 1,1-Diamino-2,2-dinitroethylene (FOX-7) has received increasing attention since it was industrialized in the late 1990s. It has lower sensitivity and comparable performance to RDX. This paper presents ballistic properties of FOX-7, its mono and dinitro derivatives and their epoxide derivatives computationally. The structures were optimized at the B3LYP/6-31G(d,p) level and the bond lengths were calculated. The calculated data for FOX-7 are compatible with the literature one. We have investigated the bond dissociation energies of the

Research paper thumbnail of Immobilization of invertase on a conducting polymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole

Reactive and Functional Polymers, 2008

In this study, immobilization of invertase was achieved on a conducting polymer of 1-(4-nitrophen... more In this study, immobilization of invertase was achieved on a conducting polymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole) (SNS (NO 2 )) via electrochemical polymerization. Kinetic parameters, maximum reaction rate (V max ) and substrate affinity (K m ), optimum temperature and pH, operational and storage stabilities of immobilized enzyme were determined.

Research paper thumbnail of JP-900 Hydroperoxidation and Decomposition

Propellants, Explosives, Pyrotechnics, 2014

Research paper thumbnail of A Review of Polycyclic Aromatic Energetic Materials

Polycyclic Aromatic Compounds, 2009

Explosives are employed extensively not only in military areas but also in civilian applications.... more Explosives are employed extensively not only in military areas but also in civilian applications. There are many researchers working on the discovery of explosives. In recent years, synthetic and theoretical studies on polycyclic aromatic explosives have received significant interest. The present short review concentrates on the synthesis and some of the physico-chemical characteristics of energetic materials of the classes of tetraazapentalene, naphthalene, di-and tetraaza-naphthalene, pyrazolo-pyrazole, benzofuroxan, tetrazine and tetrazene derivatives as well as theoretical studies. A brief comment is also made on the emerging explosive concepts such as velocity of detonation, detonation pressure etc. The compounds in the review have the potential for subsequent applications in the area of energetic materials. Therefore, an endeavor is made to assemble the important contributions made by the various scientists in the area of energetic materials in this review.

Research paper thumbnail of Design of a biosensor based on 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H pyrrole

Journal of Molecular Catalysis B: Enzymatic, 2010

Immobilization of polyphenol oxidase (tyrosinase, E.C. 1.14.18.1) was achieved on a copolymer of ... more Immobilization of polyphenol oxidase (tyrosinase, E.C. 1.14.18.1) was achieved on a copolymer of 1-(4nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole [SNS(NO 2 )] with pyrrole ([SNS(NO 2 )]/PPy) via electrochemical polymerization. Two different substrates; catechol and l-tyrosine were used for the characterization of biosensor. The kinetic parameters of the biosensor, maximum reaction rate of the enzyme (V max ) and Michaelis-Menten constant (K m ) were determined for two different substrates. V max was found as 0.02 mol/min electrode for both substrates. K m values were determined as 250 and 2 mM for catechol and l-tyrosine respectively. Calibration curves for enzyme activity versus substrate concentration were plotted between 0.05 and 0.5 M catechol and between 0.8 and 2.5 mM l-tyrosine. Optimum temperature and pH, operational and storage stabilities of immobilized enzyme were examined.

Research paper thumbnail of Prediction of Explosive Performance Properties of z -DBBD and Its Isomers by Quantum Chemical Computations

Journal of Energetic Materials, 2013

Theoretical studies have been performed on TACOT, its benzofuroxan derivative z-DBBD, and three d... more Theoretical studies have been performed on TACOT, its benzofuroxan derivative z-DBBD, and three different isomers of z-DBBD. The corrected absolute and relative total energies of the geometry-optimized structures were calculated at the theoretical level of B3LYP=6-31G(d,p). The bond dissociation energies were correlated with sensitivity. Mulliken electronegativities (v M ) and chemical hardness (g) were obtained by employing frontier molecular orbitals at the HF=6-31G(d,p)== B3LYP=6-31G(d,p) theoretical level. Detonation performance analyses for z-DBBD (4,11-dinitro[1,2,5]-oxadiazolo[3,4-e][1,2,5]oxadiazolo[3 0 ,4 0 :4,5]benzotriazolo-[2, 1-a]benzotriazol-6-ium inner salt 1,8-dioxide), its presently considered isomers, and TACOT were performed. The results showed that the performance of all compounds (compounds 1-4) was as good as that of RDX. The power index results showed that z-DBBD and its isomers were better than TACOT, RDX, and HMX. Compounds 1-4 are all reasonable candidates for high-energy-density materials (HEDMs).

Research paper thumbnail of A novel multielectrochromic copolymer based on 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole and EDOT

Journal of Electroanalytical Chemistry, 2007

Copolymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole (NTP) with 3,4-ethylene dioxythiophen... more Copolymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole (NTP) with 3,4-ethylene dioxythiophene (EDOT) was electrochemically synthesized and characterized. Resulting copolymer film has distinct electrochromic properties. It has five different colors (light red, red, light grey, green, and blue). At the neutral state k max value due to the p-p * transition was found to be 550 nm and E g was calculated as 1.6 eV. Double potential step chronoamperometry experiment shows that copolymer film has good stability, fast switching time (1.2 s) and high optical contrast (42%).

Research paper thumbnail of A theoretical study of JP-10 hydroperoxidation

Fuel, 2013

a b s t r a c t JP-10 (C 10 H 16 ) is one of cyclic, high-energy-density fuels being used in airc... more a b s t r a c t JP-10 (C 10 H 16 ) is one of cyclic, high-energy-density fuels being used in aircrafts. This single component fuel takes the advantage of increased energy storage available through its strained cyclic geometry. In recent years, the quality of petroleum feedstocks used by refineries has decreased. Examination of fuels refined by different processes has indicated that significantly higher peroxide concentrations exist in fuels which have been severely hydrotreated. Hydroperoxide concentration has been found to be a factor in fuel instability. Presently, Density Functional Theory (DFT) calculations have been carried out to investigate the mechanisms of oxidation of JP-10 through hydroperoxidation. The total electronic energies of JP-10, its related radicals and hydroperoxides produced from JP-10 have been calculated. Their thermodynamic stabilities have been discussed. The most feasible ''C center'' that would be oxidized through hydroperoxidation has been determined. It has been found that the hydroperoxides may decompose to different products having less total electronic energies.

Research paper thumbnail of Electrochemical polymerization of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1 H-pyrrole as a novel immobilization platform for microbial sensing

Bioelectrochemistry, 2009

Two types of bacterial biosensor were constructed by immobilization of Gluconobacter oxydans and ... more Two types of bacterial biosensor were constructed by immobilization of Gluconobacter oxydans and Pseudomonas fluorescens cells on graphite electrodes modified with the conducting polymer; poly(1-(4nitrophenyl)-2,5-di(2-thienyl)-1 H-pyrrole) [SNS(NO 2 )]. The measurement was based on the respiratory activity of cells estimated by the oxygen consumption at − 0.7 V due to the metabolic activity in the presence of substrate. As well as analytical characterization, the linear detection ranges, effects of electropolymerization time, pH and cell amount were examined by using glucose as the substrate. The linear relationships were observed in the range of 0.25-4.0 mM and 0.2-1.0 mM for G. oxydans and P. fluorescens based sensors, respectively.

Research paper thumbnail of A Review of Polycyclic Aromatic Energetic Materials

Http Dx Doi Org 10 1080 10406630903135971, Jul 22, 2009

Explosives are employed extensively not only in military areas but also in civilian applications.... more Explosives are employed extensively not only in military areas but also in civilian applications. There are many researchers working on the discovery of explosives. In recent years, synthetic and theoretical studies on polycyclic aromatic explosives have received significant interest. The present short review concentrates on the synthesis and some of the physico-chemical characteristics of energetic materials of the classes of tetraazapentalene, naphthalene, di-and tetraaza-naphthalene, pyrazolo-pyrazole, benzofuroxan, tetrazine and tetrazene derivatives as well as theoretical studies. A brief comment is also made on the emerging explosive concepts such as velocity of detonation, detonation pressure etc. The compounds in the review have the potential for subsequent applications in the area of energetic materials. Therefore, an endeavor is made to assemble the important contributions made by the various scientists in the area of energetic materials in this review.

Research paper thumbnail of Desensitization of TNAZ via Molecular Structure Modification and Explosive Properties - A DFT Study

Acta Chimica Slovenica, Dec 1, 2012

TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with... more TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with greater performance when compared to melt castable explosive, TNT (trinitrotoluene). Desensitization of explosives is a significant area in military use. One current method is to use additives and coatings for explosives, as in the case of RDX. Another tactic would be to attempt small molecular level chemical changes in the explosive that bring the expected decrease in sensitivity without noteworthy loss in performance. TNAZ has three nitro groups. We thought that conversion of the nitro groups to nitroso and amine groups may decrease the sensitivity. We have correlated the bond dissociation energies with sensitivity and h50 values obtained from Keshavarz relations. We have also investigated chemical hardness and Mulliken electronegativities employing the frontier molecular orbitals. Furthermore, the explosive properties, i.e. detonation velocity (D), and detonation pressure (P) have been questioned by using both Kamlet-Jacobs equations and Keshavarz relations. Detonation products and power index values have also been calculated. We have proved that molecular modification is an operative method in desensitization of TNAZ.

Research paper thumbnail of Molecular Modelling of Some Explosives and Propellants

iv I hereby declare that all information in this document has been obtained and presented in acco... more iv I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last name : Serhat VARIŞ Signature : v ABSTRACT MOLECULAR MODELLING OF SOME EXPLOSIVES AND PROPELLANTS VARIŞ, Serhat

Research paper thumbnail of On the Possibility of Autoxidation of TEX - A DFT Study

Propellants, Explosives, Pyrotechnics, 2014

Research paper thumbnail of Desensitization of TNAZ via Molecular Structure Modification and Explosive Properties - A DFT Study

Acta chimica Slovenica, 2012

TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with... more TNAZ (1,3,3-trinitroazetidine) is a highly nitrated four membered nitrogen heterocyclic ring with greater performance when compared to melt castable explosive, TNT (trinitrotoluene). Desensitization of explosives is a significant area in military use. One current method is to use additives and coatings for explosives, as in the case of RDX. Another tactic would be to attempt small molecular level chemical changes in the explosive that bring the expected decrease in sensitivity without noteworthy loss in performance. TNAZ has three nitro groups. We thought that conversion of the nitro groups to nitroso and amine groups may decrease the sensitivity. We have correlated the bond dissociation energies with sensitivity and h50 values obtained from Keshavarz relations. We have also investigated chemical hardness and Mulliken electronegativities employing the frontier molecular orbitals. Furthermore, the explosive properties, i.e. detonation velocity (D), and detonation pressure (P) have be...

Research paper thumbnail of Synthesis and characterization of a new soluble conducting polymer and its electrochromic device

Solid State Sciences, 2006

Research paper thumbnail of Synthesis and characterization of a new soluble conducting polymer and its electrochromic device

Solid State Sciences, 2006

Research paper thumbnail of A soluble conducting polymer of 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole and its electrochromic device

Thin Solid Films, 2007

A monomer 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole was synthesized via reaction of 1,4-di(2-thi... more A monomer 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole was synthesized via reaction of 1,4-di(2-thienyl)-1,4-butanedione and p-toluidine in the presence of catalytical amount of p-toluenesulfonic acid. Chemical polymerization of the monomer yielded a soluble polymer. The average molecular weight was determined by gel permeation chromatography as number average molecular weight (Mn) 2.5×103 g/mol. The monomer was also electrochemically polymerized in the presence of LiClO4, NaClO4 (1:1) as the supporting electrolyte in acetonitrile. Cyclic Voltammetry, Fourier Transform Infra Red, Nuclear Magnetic Resonance, Scanning Electron Microscopy and Ultraviolet–Visible Spectroscopy were employed for the characterization of the polymer. Spectroelectrochemistry analysis of homopolymer revealed an electronic transition at 428 nm which corresponds to π–π⁎ transition. Switching ability of the homopolymer was evaluated by kinetic studies upon measuring the percent transmittance (%T) at the maximum contrast point, indicating that poly(2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole) is a suitable material for electrochromic devices.

Research paper thumbnail of Interaction of an α-Particle with TATB

Zeitschrift für anorganische und allgemeine Chemie, 2014

Interaction of an alpha particle with triaminotrinitrobenzene (TATB) which is an insensitive expl... more Interaction of an alpha particle with triaminotrinitrobenzene (TATB) which is an insensitive explosive has been investigated by density functional calculations. It has been found that α-particles interact with TATB disturbing its planar geometry. As a result, the C-NO 2

Research paper thumbnail of A Possible Complex between TNT and Epinephrine - A DFT Study

Zeitschrift für anorganische und allgemeine Chemie, 2014

The interaction between TNT and a vitally significant biological molecule, epinephrine, was inves... more The interaction between TNT and a vitally significant biological molecule, epinephrine, was investigated at the level of density functional theory. Two models are constructed; (i) an intimate pair of TNT and epinephrine and (ii) a π complex of them. The calculations (in vacuo conditions) have showed that these molecules in the intimate

Research paper thumbnail of Nitro Derivatives of Parabanic Acid as Potential Explosives: A Theoretical Study

Zeitschrift für anorganische und allgemeine Chemie, 2014

This work deals with certain parabanic acid (PA) derivatives because they possess great calculate... more This work deals with certain parabanic acid (PA) derivatives because they possess great calculated density (Ͼ1.8 g·cm -3 ) and high content of nitrogen (26 %). Computed ballistic properties of eight different parabanic acid derivatives are presented. The structures were optimized at the B3LYP/6-31G

Research paper thumbnail of Effects of Epoxidation and Nitration on Ballistic Properties of FOX-7 - A DFT Study

Zeitschrift für anorganische und allgemeine Chemie, 2013

1,1-Diamino-2,2-dinitroethylene (FOX-7) has received increasing attention since it was industrial... more 1,1-Diamino-2,2-dinitroethylene (FOX-7) has received increasing attention since it was industrialized in the late 1990s. It has lower sensitivity and comparable performance to RDX. This paper presents ballistic properties of FOX-7, its mono and dinitro derivatives and their epoxide derivatives computationally. The structures were optimized at the B3LYP/6-31G(d,p) level and the bond lengths were calculated. The calculated data for FOX-7 are compatible with the literature one. We have investigated the bond dissociation energies of the

Research paper thumbnail of Immobilization of invertase on a conducting polymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole

Reactive and Functional Polymers, 2008

In this study, immobilization of invertase was achieved on a conducting polymer of 1-(4-nitrophen... more In this study, immobilization of invertase was achieved on a conducting polymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole) (SNS (NO 2 )) via electrochemical polymerization. Kinetic parameters, maximum reaction rate (V max ) and substrate affinity (K m ), optimum temperature and pH, operational and storage stabilities of immobilized enzyme were determined.

Research paper thumbnail of JP-900 Hydroperoxidation and Decomposition

Propellants, Explosives, Pyrotechnics, 2014

Research paper thumbnail of A Review of Polycyclic Aromatic Energetic Materials

Polycyclic Aromatic Compounds, 2009

Explosives are employed extensively not only in military areas but also in civilian applications.... more Explosives are employed extensively not only in military areas but also in civilian applications. There are many researchers working on the discovery of explosives. In recent years, synthetic and theoretical studies on polycyclic aromatic explosives have received significant interest. The present short review concentrates on the synthesis and some of the physico-chemical characteristics of energetic materials of the classes of tetraazapentalene, naphthalene, di-and tetraaza-naphthalene, pyrazolo-pyrazole, benzofuroxan, tetrazine and tetrazene derivatives as well as theoretical studies. A brief comment is also made on the emerging explosive concepts such as velocity of detonation, detonation pressure etc. The compounds in the review have the potential for subsequent applications in the area of energetic materials. Therefore, an endeavor is made to assemble the important contributions made by the various scientists in the area of energetic materials in this review.

Research paper thumbnail of Design of a biosensor based on 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H pyrrole

Journal of Molecular Catalysis B: Enzymatic, 2010

Immobilization of polyphenol oxidase (tyrosinase, E.C. 1.14.18.1) was achieved on a copolymer of ... more Immobilization of polyphenol oxidase (tyrosinase, E.C. 1.14.18.1) was achieved on a copolymer of 1-(4nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole [SNS(NO 2 )] with pyrrole ([SNS(NO 2 )]/PPy) via electrochemical polymerization. Two different substrates; catechol and l-tyrosine were used for the characterization of biosensor. The kinetic parameters of the biosensor, maximum reaction rate of the enzyme (V max ) and Michaelis-Menten constant (K m ) were determined for two different substrates. V max was found as 0.02 mol/min electrode for both substrates. K m values were determined as 250 and 2 mM for catechol and l-tyrosine respectively. Calibration curves for enzyme activity versus substrate concentration were plotted between 0.05 and 0.5 M catechol and between 0.8 and 2.5 mM l-tyrosine. Optimum temperature and pH, operational and storage stabilities of immobilized enzyme were examined.

Research paper thumbnail of Prediction of Explosive Performance Properties of z -DBBD and Its Isomers by Quantum Chemical Computations

Journal of Energetic Materials, 2013

Theoretical studies have been performed on TACOT, its benzofuroxan derivative z-DBBD, and three d... more Theoretical studies have been performed on TACOT, its benzofuroxan derivative z-DBBD, and three different isomers of z-DBBD. The corrected absolute and relative total energies of the geometry-optimized structures were calculated at the theoretical level of B3LYP=6-31G(d,p). The bond dissociation energies were correlated with sensitivity. Mulliken electronegativities (v M ) and chemical hardness (g) were obtained by employing frontier molecular orbitals at the HF=6-31G(d,p)== B3LYP=6-31G(d,p) theoretical level. Detonation performance analyses for z-DBBD (4,11-dinitro[1,2,5]-oxadiazolo[3,4-e][1,2,5]oxadiazolo[3 0 ,4 0 :4,5]benzotriazolo-[2, 1-a]benzotriazol-6-ium inner salt 1,8-dioxide), its presently considered isomers, and TACOT were performed. The results showed that the performance of all compounds (compounds 1-4) was as good as that of RDX. The power index results showed that z-DBBD and its isomers were better than TACOT, RDX, and HMX. Compounds 1-4 are all reasonable candidates for high-energy-density materials (HEDMs).

Research paper thumbnail of A novel multielectrochromic copolymer based on 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole and EDOT

Journal of Electroanalytical Chemistry, 2007

Copolymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole (NTP) with 3,4-ethylene dioxythiophen... more Copolymer of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1H-pyrrole (NTP) with 3,4-ethylene dioxythiophene (EDOT) was electrochemically synthesized and characterized. Resulting copolymer film has distinct electrochromic properties. It has five different colors (light red, red, light grey, green, and blue). At the neutral state k max value due to the p-p * transition was found to be 550 nm and E g was calculated as 1.6 eV. Double potential step chronoamperometry experiment shows that copolymer film has good stability, fast switching time (1.2 s) and high optical contrast (42%).

Research paper thumbnail of A theoretical study of JP-10 hydroperoxidation

Fuel, 2013

a b s t r a c t JP-10 (C 10 H 16 ) is one of cyclic, high-energy-density fuels being used in airc... more a b s t r a c t JP-10 (C 10 H 16 ) is one of cyclic, high-energy-density fuels being used in aircrafts. This single component fuel takes the advantage of increased energy storage available through its strained cyclic geometry. In recent years, the quality of petroleum feedstocks used by refineries has decreased. Examination of fuels refined by different processes has indicated that significantly higher peroxide concentrations exist in fuels which have been severely hydrotreated. Hydroperoxide concentration has been found to be a factor in fuel instability. Presently, Density Functional Theory (DFT) calculations have been carried out to investigate the mechanisms of oxidation of JP-10 through hydroperoxidation. The total electronic energies of JP-10, its related radicals and hydroperoxides produced from JP-10 have been calculated. Their thermodynamic stabilities have been discussed. The most feasible ''C center'' that would be oxidized through hydroperoxidation has been determined. It has been found that the hydroperoxides may decompose to different products having less total electronic energies.

Research paper thumbnail of Electrochemical polymerization of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1 H-pyrrole as a novel immobilization platform for microbial sensing

Bioelectrochemistry, 2009

Two types of bacterial biosensor were constructed by immobilization of Gluconobacter oxydans and ... more Two types of bacterial biosensor were constructed by immobilization of Gluconobacter oxydans and Pseudomonas fluorescens cells on graphite electrodes modified with the conducting polymer; poly(1-(4nitrophenyl)-2,5-di(2-thienyl)-1 H-pyrrole) [SNS(NO 2 )]. The measurement was based on the respiratory activity of cells estimated by the oxygen consumption at − 0.7 V due to the metabolic activity in the presence of substrate. As well as analytical characterization, the linear detection ranges, effects of electropolymerization time, pH and cell amount were examined by using glucose as the substrate. The linear relationships were observed in the range of 0.25-4.0 mM and 0.2-1.0 mM for G. oxydans and P. fluorescens based sensors, respectively.