scholarly journals On the influence of temperature and chemical properties on viscosity of Moravian wines

Author(s):  
Miroslav Havlíček ◽  
Libor Severa ◽  
Ivo Křivánek

Standard chemical analysis was performed to characterise six samples of bottled wines from South Moravia. Temperature influence (range from 20 °C to 50 °C). Density data processing led to determination of the expansibility coefficients at 25 °C and their temperature dependence. It was found that, viscosity of wine decreases non-linearly with increasing temperature. Fitting of the experimental data in some theoretical models was performed in order to describe the temperature dependence of the viscosity of wine. A modified Andrade equation was found to best describe this dependence. The activation energy for viscous flow of wine, calculated by Arhenius relation, varied from 18.50 kJ.mol–1 to 20.15 kJ. mol–1. Correlations between the activation energy for viscous flow and the concentrations of solutes other than ethanol were estimated.

Author(s):  
O.S. Bezuglova ◽  

Rostov Region belongs to the highly protected natural territories characterized by the continuous plowing. There territories are the only reserves with the soils preserved in their natural state. However, these areas often lack detailed information about the soils quality and composition. Surveying soils on these territories is crucial for determination of their basic physical and chemical properties. The resulted compilation of soil maps could lay a foundation for creating the Red Book of Soils and the formation of a section in the soil-geographical database of the Russian Federation. Subsequently, such information can be used as a background data for the main types of soils in the region. It will be also valuable during monitoring and justification of conservation measures.


2014 ◽  
Vol 70 (a1) ◽  
pp. C141-C141
Author(s):  
Ozen Ozgen ◽  
Engin Kendi ◽  
Semra Koyunoglu ◽  
Akgul Yesilada ◽  
Hwo-Shuenn Sheu

A significant part of medicine is based on the discovery and development of drugs. It is very important to know the crystal structure of pharmaceutical compounds for fundamental understanding of structure, physical and chemical properties. Many of these materials are available only as powders. So any structural information must be obtained from powder diffraction. I am going to present following the stages while solving the structure of C23H19N4OBr, 2-[3-phenyl-4(m-bromophenyl)-2-pyrazolin-1-yl]-3-methyl-4(3H)-quinazolinone, from 2-pyrazolines derivatives. The compounds are known to display various biological properties such as fungicidal insecticidal, anti bacterial, anti viral activities, pharmacological properties such as antiinflammatory agents and have industral properties(1). The powder diffraction data was collected with Debye Scherrer camera at the BL01C2 beamline at room temperature in National Synchrotron Radiation Research Center(NSRRC), Taiwan. X-ray of wavelength was 1.0333Å. This compound crystallizes in orthorhombic system space group P bca, Z=8, unit cell parameters of a=25.83(1)Å, b=15.55(5)Å, c=10.63(3)Å, and V=4266.0(10)Å3. Reliability factors were reached Rwp=0.075, Rp=0.053, RB=0.086 ve S=1.31 after Rietveld refinement.


2016 ◽  
Vol 61 (No. 3) ◽  
pp. 99-105 ◽  
Author(s):  
M. Müller ◽  
Š. Horníčková ◽  
P. Hrabě ◽  
J. Mařík

The research was performed to examine the physical, mechanical and chemical properties of seeds and kernels of Jatropha curcas. The test parameters were the dimensions of the seeds and kernels, required energy for oil extraction, determination of fatty acids in the oil by gas chromatography method, determination of the iodine value, determination of the acid value, determination of total polyphenols by the Folin & Ciocault reagent and determination of tocopherols and tocotrienols (vitamin E) by High-performance liquid chromatography. It was ascertained that the size of the seed and kernel varies considerably. Pressing of whole seeds needs more energy (50%) than pressing of kernels. From a chemical point of view it seems to be very appropriate for a production of biofuels. Jatropha curcas contains more polyphenols and vitamin E, which act as antioxidants, than the rape. Due to the low content of unsaturated fatty acids it is chemically suitable to replace the rape-seed oil with Jatropha curcas oil.


Author(s):  
Kaplaushenko Tm ◽  
Panasenko Oi ◽  
Kucheryavy Yu

ABSTRACTObjective: Fundamental research in pharmacy and medicine have shown that drugs, which are based on nucleus of the 1,2,4-triazole, have a widerange of biological effects. Derivatives of this heterocyclic system have well-known Ukrainian clinicians and the world scientists due to its antifungal,antidepressant, anticancer, cardio- and hepatoprotective properties. The pharmacological activity of most organic compounds depends on severaldifferent factors, including bioavailability of the substance. Hence, it is very important to consider the results of the synthetic and biological researchesand established dependence of structure on the biological action when scientists model new molecules or improve pharmacological properties of anexisting structure. One of the important social and economic problems of the pharmaceutical industry is the implementation in practice of new drugsthat could compete with expensive imported drugs. In recent times, 1,2,4-triazole-3-thioderivatives take attention of compatriots and scientists offoreign countries who are working on finding bioactive compounds including heterocyclic systems. The structure, physical and chemical properties,pharmacological activities of 1,2,4-triazoles, and their 3-thioderivatives are understudied. Hence, the study of that will be actually and novelty formodern science. The main purpose of our research is synthesis of 3-alkylsulfonyl-5-(chinoline-2-yl, 2-hydroxychinoline-4-yl)-4-R-2,4-dihydro-3N1,2,4-triazoles,studyingof its physicaland chemical properties.Methods: The initial compounds have been synthesized previously using known in literature techniques. Oxidation of the sulfur atom of thesynthesized compounds to the hexavalent condition was carried out adding solution of hydrogen peroxide.Results: The structure of the obtained compounds was determined with the modern physical and chemical analysis methods: Element analysis,infrared-spectrophotometry, and their individuality with thin layer chromatography.Conclusions: Prospect of the further researches is determination of acute toxicity and next studying of pharmacological properties of the synthesizedcompounds.Keywords: 1,2,4-triazoles, Synthesis, Chemical properties, Chinoline.1 


1993 ◽  
Vol 47 (10) ◽  
pp. 1720-1727 ◽  
Author(s):  
Jie Lin ◽  
Chris W. Brown

Near-IR spectroscopy has been investigated as a universal approach for determination of physical and chemical properties of water and their functions of temperature. Principal component regression and multilinear regression models were used to correlate the spectra with the properties of water at temperatures between 5 and 65°C. Fifteen properties of water were investigated including density, refractive index, dielectric constant, relative viscosity, surface tension, vapor pressure, sound velocity, isothermal compressibility, thermal expansivity, thermal capacity, thermal conductivity, enthalpy, free energy, entropy, and ionization constant. Very good correlations were found between the near-IR predicted values of all the properties and those obtained by the traditional methods. This investigation demonstrates that these fifteen properties of water can be simultaneously determined simply by measuring a set of near-IR spectra of water, and, thus, near-IR spectroscopy can be used as a universal method for the determinations of physical and chemical properties of water. Remote sensing of the properties can be performed with the use of a fiber-optic sensor.


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