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Quantum-chemical Calculations of the Antioxidant Properties of trans-p-coumaric Acid and trans-sinapinic Acid

Urbaniak A., Molski M., Szeląg M.

Computational Methods in Science and Technology

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2012

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Vol. 18, No. 2

XX-XX

EN

Trans-p-coumaric and trans-sinapinic acids are cinnamic acid's derivatives which show strong antioxidant properties. In this work full optimization of both chemical structures and their radical, cation radical and anionic forms in vacuum and water medium has been performed, and antioxidant descriptors: Bond Dissociation Enthalpy, Adiabatic Ionization Potential, Proton Dissociation Enthalpy, Proton Affinity, Electron Transfer Enthalpy, Gas Phase Acidity, Free Gibbs Energy have been calculated. The Highest Occupied and Lowest Unoccupied Molecular Orbital energies have been employed to determine groups in compounds studied with the highest electron density. All calculations were performed using Gaussian 03W software package at the DFT level of theory (B3LYP hybrid functional) together with 6-311+G(2d,2p) basis set. Strong antioxidant properties of both investigated compounds were determined in this study. Based on the results it may be suggested that trans-p-coumaric and transsinapinic acids react according to the Hydrogen Atom Transfer mechanism in vacuum and according to SingleElectron Transfer followed by the Proton Transfer mechanism in water medium. Moreover, in both compounds studied the O-H bond is a preferred place of free radical attack.

2

Concentrations and profiles of brominated diphenyl ethers (BDEs) in Baltic and Atlantic herring

Roots O., Zitko V., Kiviranta H., Rantakokko P., Ruokojärvi P.

Oceanologia

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2009

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No. 51 (4)

515-523

EN

The total concentrations of BDEs in Baltic herring, caught in different years (2002-08) from various areas of the Baltic, and in Atlantic herring (2006) can be reasonably well described by a single concentration vs weight relationship. Samples collected a few years earlier and analysed by others show a slightly different relationship. This indicates that the weight of the fish is an important factor determining the level of contamination and that the contamination apparently did not increase between 1999 and 2008. However, two Baltic herring samples collected in 2007 contained, for reasons unknown, very high concentrations of BDE 209. The BDE profiles (concentrations scaled to a sum of 100) varied a great deal. It is impossible to determine how much of this variation is real and how much is caused by errors in the analyses. The concentration of the BDE 75 was much higher in the Atlantic than in the Baltic herring. Even after taking this into consideration, however, the BDE profile in Atlantic herring is different from the BDE profiles in Baltic herring.

3

Aplikacja dydaktyczna zarządzania bazą danych z automatycznym generowaniem zapytań

Brzozowski W.

Informatyka Teoretyczna i Stosowana

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2007

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R. 7, nr 12

109-120

PL

W artykule opisano aplikację dydaktyczną generującą i obsługującą wielotabelową lokalną bazę danych z poziomu środowiska Delphi. Celem aplikacji jest nauczanie języka SQL oraz jednej z technologii bazodanowych w środowisku Delphi. Oryginalność aplikacji polega na modułach automatycznego generowania zapytań. Aplikacja umożliwia wybór przez studenta jednego, z setek wariantów zapytań poprzez ustawienie odpowiednich opcji komponentów. Aplikacja generuje następnie pełny skrypt zapytania w języku SQL i odwołuje się do SZBD celem re3Ilzacji tego zapytania. Student ma w ten sposób możliwość zapoznania się z poprawną składnią zapytania w bardzo wielu możliwych wariantach.

EN

The didactic application, that generates and manages multitable local database, from the level or Delphi environment, bas been presented in the paper. The purpose or this application is teaching or the SQL language and or one or the database technologies in the Delphi environment. Originality or the application consists in modules or automatic generation or queries. The application allows a student to choose one from hundreds variants or query, through the setting of component properties. The application generates then full script or the query in the SQL language and appeals to DBMS for execution or this query. The student bas this war possibility to acquaint with the proper syntax or query in many possible variants.

4

Efficiency of Technology of Access to Databases

Barczak A., Mościcki A.

Studia Informatica : systems and information technology

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2006

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Vol. 1(7)

293--310

EN

In this paper the evolution of technologis of access to databases is presented. For definite systems of databases’ management (databases servers) and technologis of access, there was made an experiment, enabling to estimate the average of time of answering (realizing), definite types of questions- what means efficiency of each technologis.