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Volodymyr?DibrivnyiEmail author Iryna?Sobechko Marian?Puniak Yuriy?Horak Mykola?Obushak Yuriy?Van-Chin-Syan Marshalek?Andriy Nadiia?Velychkivska 《Chemistry Central journal》2015,9(1):67
Background
The aim of the current work was to determine thermo dynamical properties of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde.Results
The temperature dependence of saturated vapor pressure of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde was determined by Knudsen’s effusion method. The results are presented by the Clapeyron–Clausius equation in linear form, and via this form, the standard enthalpies, entropies and Gibbs energies of sublimation and evaporation of compounds were calculated at 298.15 K. The standard molar formation enthalpies of compounds in crystalline state at 298.15 K were determined indirectly by the corresponding standard molar combustion enthalpy, obtained using bomb calorimetry combustion.Conclusions
Determination of the thermodynamic properties for these compounds may contribute to solving practical problems pertaining optimization processes of their synthesis, purification and application and it will also provide a more thorough insight regarding the theoretical knowledge of their nature.
94.
Franklin E. Leach Andriy Kharchenko Ron M. A. Heeren Eugene Nikolaev I. Jonathan Amster 《Journal of the American Society for Mass Spectrometry》2010,21(2):203-208
It has been previously observed that the measured frequency of ions in a Fourier transform mass spectrometry experiment depend
upon the number of trapped ions, even for populations consisting exclusively of a single mass-to-charge. Since ions of the
same mass-to-charge are thought not to exert a space-charge effect among themselves, the experimental observation of such
frequency shifts raises questions about their origin. To determine the source of such experimentally observed frequency shifts,
multiparticle ion trajectory simulations have been conducted on monoisotopic populations of Cs+ ranging from 102 ions to 106 ions. A close match to experimental behavior is observed. By probing the effect of ion number and orbital radius on the shift
in the cyclotron frequency, it is shown that for a monoisotopic population of ions, the frequency shift is caused by the interaction
of ions with their image-charge. The addition of ions of a second mass-to-charge to the simulation allows the comparison of
the magnitude of the frequency shift resulting from space-charge (ion-ion) effects versus ion interactions with their image
charge. 相似文献
95.
Kolattukudy Poulose Santo Andriy Kovalenko Maria Stepanova 《Macromolecular theory and simulations》2010,19(5):228-239
Three‐dimensional mesoscopic morphologies and the thermodynamics of structural phase transitions of amphiphilic lipids at air‐water interfaces are studied using self‐consistent field theory. Changing the relative amount of lipids in the system led to a series of 3D morphologic phases with varying average interfacial area per molecule, mimicking a compression of the model membranes. Membranes of both saturated and unsaturated lipids undergo a transition from cylindrical micelle to lamella when the lipid content in the system increases from 2% to about 19–20%. With further increase in the lipid content, saturated lipids first develop non‐uniform quasi‐2D distributions in the lamella and then gradually transform into a hybrid morphology containing quasi‐planar lamellae. In contrast, unsaturated lipids develop reverse‐micellar morphologies.
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97.
Halyna Shkil Leonard Stoica Kostyantyn Dmytruk Oleh Smutok Mykhailo Gonchar Andriy Sibirny Wolfgang Schuhmann 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,76(1-2):175
In general, L-lactate respiration is difficult to detect in living yeast cells due to the small activity of L-lactate oxidizing enzymes within the mitochondria. Genetically modified cells of methylotrophic yeast Hansenula polymorpha overproducing L-lactate:cytochrome c-oxidoreductase (EC 1.1.2.3, also known as flavocytochrome b2, FC b2) were physically immobilized by means of a dialysis membrane onto various types of electrode materials in order to investigate the possibility of electrochemically detecting L-lactate respiration. It could be shown that in the case of genetically modified Hansenula polymorpha cells in contrast to cells from the parental strain, enhanced L-lactate-dependent respiration could be detected. Due to overproduction of FC b2 the O2 reduction current is decreased upon addition of L-lactate to the electrolyte solution. The electron transfer pathway in the L-lactate-dependent respiration process involves a cascade over three redox proteins, FC b2, cytochrome c and Complex-IV, starting with L-lactate oxidation and ending with oxygen reduction. By means of selective inhibition of Complex IV with CN−, lactate respiration could be proven for causing the decrease in the O2 reduction. 相似文献
98.
A novel approach to design and optimize linear multicapillary arrays (LMCAs) for high-throughput DNA sequencing is proposed. A significant increase in the number of capillary lanes is obtained due to the use of composite insertions alternately placed between working capillaries of the array and a specific combination of refractive indices of the DNA separation matrix, capillary glass, the insertions and a medium which surrounds the capillary array. Theoretical and experimental studies showed that in conjunction with a dual-side laser illumination scheme, the proposed LMCA design allows a simultaneous uniform irradiation of as many as 550 working capillaries. 相似文献
99.
Voronov A Kohut A Peukert W Voronov S Gevus O Tokarev V 《Langmuir : the ACS journal of surfaces and colloids》2006,22(5):1946-1948
We synthesized and characterized novel amphiphilic polyesters with both hydrophilic and hydrophobic functionalities. The polyesters are soluble in organic and aqueous media and reveal the formation of inverse architectures whose behavior could be correlated to their chemical structure. We foresee that the amphiphilic properties of the polyesters reported here are obviously the basis of new architectures both in solution and on the solid surfaces, which could be used in a broad range of applications. The described synthesis of the copolymers is very simple and is based on commercially available products. That makes this approach attractive in various uses. 相似文献
100.
Dürr C Schnell HJ Luzhetskyy A Murillo R Weber M Welzel K Vente A Bechthold A 《Chemistry & biology》2006,13(4):365-377
Phenalinolactones are terpene glycosides with antibacterial activity. A striking structural feature is a highly oxidized gamma-butyrolactone of elusive biosynthetic origin. To investigate the genetic basis of the phenalinolactones biosynthesis, we cloned and sequenced the corresponding gene cluster from the producer strain Streptomyces sp. Tü6071. Spanning a 42 kbp region, 35 candidate genes could be assigned to putatively encode biosynthetic, regulatory, and resistance-conferring functions. Targeted gene inactivations were carried out to specifically manipulate the phenalinolactones pathway. The inactivation of a sugar methyltransferase gene and a cytochrome P450 monoxygenase gene led to the production of modified phenalinolactone derivatives. The inactivation of a Fe(II)/alpha-ketoglutarate-dependent dioxygenase gene disrupted the biosynthetic pathway within gamma-butyrolactone formation. The structure elucidation of the accumulating intermediate indicated that pyruvate is the biosynthetic precursor of the gamma butyrolactone moiety. 相似文献