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WOS: 000389768800022, In this pure theoretical study, a hitherto unexplored equation based on Shannon radii of the ions forming that crystal and chemical hardness of any crystal to calculate the lattice energies of simple inorganic ionic crystals has been presented. To prove the credibility of this equation, the results of the equation have been compared with experimental outcome obtained from Born-Fajans-Haber- cycle which is fundamentally enthalpy-based thermochemical cycle and prevalent theoretical approaches proposed for the calculation of lattice energies of ionic compounds. The results obtained and the comparisons made have demonstrated that the new equation is more useful compared to other theoretical approaches and allows to exceptionally accurate calculation of lattice energies of inorganic ionic crystals without doing any complex calculations.

WOS: 000394063300047, Lattice energy and bond stretching force constant are two quantities considered in many fields of chemistry and physics. Both quantities can be used to describe the stability or reactivity of a simple system. In the present study, by inspecting the correlation between lattice energies and bond stretching force constants for some sets of simple ionic molecules having similar bonding type, we present simple and useful equations to estimate the bond stretching force constants of simple ionic compounds. In order to determine lattice energies taken into account in this study, Born-Haber-Fajans (BHF) thermochemical cycle and lattice energy equations proposed by Jenkins and Kaya were used. It is shown that bond force constant of a simple ionic compound can be easily calculated in agreement with its spectroscopic counterpart through its lattice energy value. Percentage deviation values determined considering calculated and observed bond stretching force constants for the tested ionic compounds are pretty small except of some molecules like cesium halides (CsF, CsCl, CsBr). Such small values of percentage deviation probe the reliability and validity of the correlation between lattice energy and bond stretching force constant. (C) 2016 Elsevier Ltd. All rights reserved., Millennium Science Initiative (ICM, Chile); FONDECYT (Chile); UNAB [NC120082, 1140343, UNAB DI-806-15/R], EC thank the Millennium Science Initiative (ICM, Chile), FONDECYT (Chile) and UNAB through Grant Nos. NC120082, 1140343 and UNAB DI-806-15/R, respectively.

WOS: 000388046800055, This study consists of two parts. In the first part, the inhibitive performance of six mono-azo dye (MAD_ 1 6 ) derivatives was investigated experimentally (gravimetric, thermometric, UVvisible spec-trophotometric and electrochemical potentiostatic methods) and computationally against corrosion of Fe metal in 2 M HNO3 and 2 M NaOH solutions. Density functional theory (DFT) calculations and molec-ular dynamics simulation (MDS) approach were performed. Quantum chemical parameters such as the highest occupied molecular orbital energy (E-HOMO ), lowest unoccupied molecular orbital energy (E-LUMO), the energy gap between E-LUMO and E-HOMO (Delta E ), dipole moment (D ), chemical hardness (eta), softness (sigma), electronegativity (chi), proton affinity, global electrophilicity (omega), global nucleophilicity (epsilon) and total energy (sum of electronic and zero-point energies) were calculated and discussed with the help of HF/SDD, HF/6-311 G, HF/6-31++G, B3LYP/SDD, B3LYP/6-311 G and B3LYP/6-31++G methods. Polarization measurements indicate that (MAD) compounds are of mixed-type inhibitor in acidic, act mainly as cathodic in alkaline solution. Kinetic model involving binding constant (K-b ), active sites (1/y) and standard free energy values of adsorption (Delta G degrees) were compared with the parameters of equilibrium constant (K-ads ), lateral interac-tion (f ) and (Delta G degrees), that obtained from Frumkin adsorption isotherm model. Then, we calculated binding energies on Fe (110) surface of the inhibitors. The theoretical data obtained are in good agreement with the experimental inhibition efficiency results., Faculty of Science, Department of Chemistry at Baljarashi, Al-Baha University, (Saudi Arabia); Faculty of Science, Department of Chemistry at Cumhuriyet University (Turkey); Faculty of Science, Department of Chemistry at Tongren University (China), I gratefully acknowledge Faculties of Science, Departments of Chemistry at Baljarashi, Al-Baha University, (Saudi Arabia), Cumhuriyet University (Turkey), and Tongren University (China), for the financial assistance and facilitation of our research.

WOS: 000380624500053, The adsorption and corrosion inhibition properties of three piperidine derivatives namely, (1-(5-fluoro-2-(methylthio) pyrimidine-4-yl) piperidine 4 yl) 2,5-dimethoxybenzenesulfonamide (FMPPDBS), (1-(5-fluoro-2-(methylthio) pyrimidine-4-yl) piperidine-4-yl)-4-nitrobenzenesulfonamide (FMPPNBS), (1-(5-fluoro-2-(methylthio) pyrimidine-4-yl) piperidine-4-yl)-3-methoxybenzenesulfonamide (FMPPMBS) on the corrosion of iron were investigated by performing quantum chemical calculations and molecular dynamics simulations. Global reactivity parameters such as E-HOMO, E-LUMO, HOMO-LUMO energy gap (Delta E), chemical hardness, softness, electronegativity, proton affinity, electrophilicity and nucleophilicity have been calculated and discussed. The adsorption behaviors of these piperidine derivatives on Fe(110), Fe(100) and Fe(111) surfaces were investigated using molecular dynamics simulation. The binding energies on metal surface of studied compounds followed the order: FMPPDBS > FMPPMBS> FMPPNBS and this ranking obtained is consistent with the experimental data. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

WOS: 000369196100061, Amino acids are biologically important organic compounds in the human body which contain two important functional groups namely: -NH2 (amine) and -COOH (carboxylic acid) in their structures. In the present work, corrosion inhibitive performance amino acids such alanine (Ala), methionine (Met), aspartate (Asp), asparagine (Asn), lysine (Lys), arginine (Arg) and histidine (His) were investigated. All quantum chemical calculations related to these amino acids at the B3LYP/6-31G++(d, p) HF/6-31G++(d,p) methods were performed. Corrosion inhibition effects of the subject amino acids were discussed not only in the gas phase but also in the water phase, acetic acid and formic acid. Furthermore, molecular dynamic simulations employing Monte Carlo sampling approach were applied to search for the most stable configuration and adsorption energies for the interaction of the amino acid corrosion inhibitors on Cu (111)/50 H2O interface. A good correlation between theoretical data and experimental data has been obtained. Moreover, arginine that is a basic amino acid the best corrosion inhibitor among amino acids, considered in this study. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

WOS: 000353745400010, The chemical hardness introduced by Pearson in 1960s is an extremely useful theoretical descriptor. It is apparent that principles such as hard and soft acids and bases (HSAB) and maximum hardness principle (PMH) related with the chemical hardness provide theoretical justifications and explanations for many issues in chemistry. In the present report, a new molecular hardness equation to calculate chemical hardness of functional groups and molecules is derived utilizing the relationship with charge of the electronic energy for atoms, Density Functional Theory, and Datta's global hardness equalization principle. The reliability of the new equation is assessed by comparison with experimental data, the results of Datta's geometric mean equation, and molecular hardness values obtained in the present work. The new equation provides the opportunity to calculate the chemical hardness of molecules from first ionization energies (IE1), first electron affinities (EA(1)) and second ionization energies (IE2) of atoms in the molecules. (C) 2015 Elsevier B.V. All rights reserved.

WOS: 000348089200007, In particular, in organic chemistry, the electronegativity of functional groups are taken into consideration significantly to predict reaction mechanism and to explain inductive effects of functional groups. In the present study, considering the relationship with charge of the electronic energy for atoms, Sanderson's electronegativity equalization principle and Density Functional Theory (DFT), we have obtained a new equation by which group electronegativity can be calculated from ionization energies (I) and electron affinities (A) of atoms that constitute the group, where the results obtained were compared with equation of Sanderson who proposed that group electronegativity is the geometric mean of atomic electronegativities. For a large number of groups, it was found to be a very close agreement with a standard deviation of 0.12. The advantage of the present equation is that it can be used for ionic groups. In addition, the derived equation can be used to calculate Mulliken and Pauling electronegativities of molecules. (C) 2014 Elsevier B.V. All rights reserved., department of chemistry of Cumhuriyet University, This research was supported by department of chemistry of Cumhuriyet University.

Malondialdehyde (MDA) is a reliable marker of lipid peroxidation where paraoxonase and arylesterase are two enzymes against it. Although increased MDA has been previously shown in adults with attention deficit/hyperactivity disorder (A-ADHD), levels of paraoxonase and arylesterase enzymes have not been studied yet. We aimed to determine the status of both MDA level and paraoxonase and arylesterase enzyme activities in A-ADHD patients. A total of 35 adults with ADHD diagnosis according to Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV) criteria and 29 healthy volunteers were included in the study. Serum MDA, paraoxonase and arylesterase levels of the participants were measured. The disease severity of the patients was determined by using Turgay's Adult Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder (ADD/ADHD) DSM IV Based Diagnostic Screening and Rating Scale. The serum MDA level of patients was significantly higher than that of healthy control subjects, whereas their paraoxonase and arylesterase levels were significantly lower. There was no correlation between the levels of biochemical parameters (MDA, paraoxonase and arylesterase) and the disease severity. Sub-types of A-ADHD were similar in terms of these biochemical parameters. Increased lipid peroxidation, a part of oxidative stress, in adults with ADHD appears to be unbuffered by antioxidant enzymes, namely paraoxonase and arylesterase.

Highlights • Splenic hilar dissection which is a part of D2 lymphadenectomy has a remarkable role in the curative surgical treatment of gastric cancer. • Splenic infarction occurs secondary to any injury to splenic vascular structures and has numerous etiologies. • There has been reported no article about splenic infarction following gastric surgery. Incidence of this complication is still unknown. • New generation technologies have a major role in surgical area. Particularly, dissection of most regions during surgical resection is performed using vessel sealer device, which is popular in the current surgical era. • Postoperative acute abdominal pain radiating to left shoulder following gastric surgery should be considered as a sign of possible splenic complication., Introduction The dissection of splenic hilar lymph nodes in gastric cancer surgery is indispensable for treating gastric cancers located in the proximal third of the stomach. Splenic vascular injury is a matter of debate resulting on time or delayed splenectomy. We aimed to share our experience and plausible mechanisms causing this complication in two case reports. Case presentations Two male patients with gastric cancer were diagnosed with acute splenic infarction following gastric surgery in the early postoperative period. Both underwent emergent exploratory laparotomy. Splenectomy was performed due to splenic infarction. Discussion Because we observed this rare complication in recent patients whose surgery was performed using vessel-sealing device for splenic hilar dissection, we suggested that extensive mobilization of the surrounding tissues of splenic vascular structures hilum using the vessel sealer could be the reason. Conclusion In case of acute abdominal pain radiating to left shoulder, splenic complications should be taken into consideration in gastric cancer patients performed radical gastrectomy. Meticulous dissection of splenic hilar lymph nodes should be carried out to avoid any splenic vascular injury.

WOS: 000280847000016, The maximum value of the sum of the interaction constants is used as an additional constraint to solve the CO-factored force fields of tricarbonyl complexes with C-s symmetry. The solution obtained led to the equations by which carbonyl stretching force constants and CO-CO interaction constants can be calculated directly from C-O stretching frequencies of the all-(CO)-C-12-O-16 molecule. The CO-factored force constants and the C-O stretching frequencies of (CO)-C-13-O-16-substituted species were calculated for Fe(CO)(3)(-) and Fe(C4H6)(CO)(3). The results obtained were found to be very close agreement with those obtained from isotopic enrichment studies. (C) 2010 Elsevier B. V. All rights reserved., Research Project Foundation of Cumhuriyet University [F-234], We thank Professor J. Mink for helpful discussion and normal coordinate analysis's results; we also thank Research Project Foundation (no. F-234) of Cumhuriyet University for financial supports

Arils from six pomegranate ( Punica granatum L.) cultivars obtained from various sites from the Mediterranean region of Turkey were evaluated for their chemical and antioxidant properties. These properties included total phenolics (TP), total monomeric anthocyanins (TMA), soluble solids (TSS), titratable acidity (TA), individual sugars and organic acids. Antioxidant capacities of arils were determined by both the ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) assays. The antioxidant capacities averaged 5.60 and 7.35 mmol TE/l by the TEAC and FRAP methods. Variability among cultivars was greatest for TMA content (CV 132%); individuals ranged from 6.1 to 219 mg cy3-Gluc l −1 . TP means averaged 1507 mg GAE/l. Levels of FRAP, TEAC, TP, and TMA were strongly correlated ( r = 0.82–0.96). The major sugars were fructose (6.4 g/100 ml) and glucose (6.8 g/100 ml), the major acids were citric (1.78 g/100 ml) and malic (0.12 g/100 ml).

WOS: 000178258500022, Using an analytical approach we were able to obtain a valid solution to the CO-factored force field of Fe(CO)(5). The solution led to the relations which allow direct calculation of the CO-factored force constants from C-O stretching frequencies of the all-(CO)-C-12-O-16 molecule. The force constants calculated from these relations were used to estimate C-O stretching frequencies of (CO)-C-13-O-16- substituted species of Fe(CO)(5). The results were found to be in very close agreement with those obtained from isotopic spectra. (C) 2002 Elsevier Science B.V. All rights reserved.

WOS: 000079149100007, The CO-factored force field of M(CO)(4) molecules with C-3 nu symmetry was solved using the maximum value of the sum of the interaction constants as an additional constraint. The solution obtained led to the relations which allow direct calculation of force constants from C-O stretching frequencies of the all-(CO)-C-12-O-16 molecule. The CO-factored force constants and C-O stretching frequencies of (CO)-C-13-O-16-substituted species were calculated for Co(CO)(4) and Fe(CO4-). The results were found to be in very close agreement with those obtained from isotopic enrichment studies. (C) 1999 Elsevier Science S.A. All rights reserved.

The Ihlara Valley is situated within a volcanic arc that is formed by the collision of the eastern Mediterranean plate system with the Anatolian plate. In this study we will present data from a reservoir monitoring project over the Ihlara-Ziga geothermal field, located 22 km east of Aksaray, in central Anatolia. Although identified geothermal resources in the Ihlara Valley are modest, substantial undiscovered fields have been inferred primarily from the volcanic and tectonic setting but also from the high regional heat flow (150–200 mWm−2) on the Kirsehir Massif. In 1988 and 1990, geoelectromagnetic surveys were undertaken by MTA-Ankara to confirm the presence of a relatively shallow (≈ 0.5–1 km), hydrothermally caused conductive layer or zone. CSAMT and Schlumberger resistivity data show good correspondence with each other, and 2-D geoelectric models are also in harmony with geologic data and gravity anomalies. The depth of the resistive basement, which is interpreted as Paleozoic limestone, is 200–250 m in the western part and increases eastward (≈ 600–750 m). This may imply N-S-oriented normal faulting within the survey area. The parameters of the top layer are a resistivity of 25 to 95 ohm m and a thickness of between 100 and 250 m. The thickness of the conductive tuffs between the top layer and the basement, whose resistivity is about 4–5 o hmm, also increases eastward (from 100 to 450 m). The apparent resistivity maps for the frequencies between 32 and 2 Hz reveal a localized low resistivity anomaly to the east of Belisirma.

WOS: A1994NK71600011, Using an analytical approach we have been able to obtain a valid solution to the secular equations for cis-ML2(CO)4 molecules. The solution has led to the relations by which carbonyl stretching force constants and interaction constants can be calculated directly from (CO)-C-12-O-16 stretching frequencies. It has been found that calculated force constants are in excellent agreement with those obtained from isotopic enrichment studies and exactly equal to those calculated through the iterative procedure employed by Jernigan et al.