scholarly journals Prediction of Physico-chemical Properties of Bacteriostatic N1-Substituted Sulfonamides: Theoretical and Experimental Studies

2017 ◽  
pp. 842-848
Author(s):  
Hossein Nikoofard ◽  
Mohsen Sargolzaei ◽  
Farnosh Faridbod
Keyword(s):  
Experimental Studies ◽  
Chemical Properties ◽  
Physico Chemical

scholarly journals Effects of fluoride salt addition to the physico-chemical properties of the MgCl2-NaCl-KCl heat transfer fluid : a molecular dynamics study

2021 ◽  
Author(s):  
Weiguang Zhou ◽  
Yanping Zhang ◽  
Mathieu Salanne
Keyword(s):  
Heat Transfer ◽  
Molecular Dynamics ◽  
Experimental Studies ◽  
Chemical Properties ◽  
Heat Transfer Fluid ◽  
Electricity Production ◽  
Fluoride Ions ◽  
Heat Transfer Fluids ◽  
Physico Chemical ◽  
Dynamics Simulations

Concentrated solar plants are promising solutions for electricity production. In these plants, the heat transfer fluid plays an important role, and finding systems with good thermal properties is very important. In this regard, molten salts, and more particularly molten chlorides, are currently investigated. Experimental studies of these melts are difficult and expensive, so complementing them with simulations would allow to test a wider range of compositions. In this work, we show that classical molecular dynamics simulations are suitable for predicting the properties of a ternary salt composed of MgCl2, KCl and NaCl by extensive comparisons with experimental data (and previous simulations) on the density, heat capacity, viscosity and thermal conductivity. We then study the effect of adding fluoride ions in the melt on these properties in order to investigate the suitability of mixed chlorides-fluorides for future heat transfer fluids studies.

scholarly journals State-of-the-Art Review of Effervescent-Swirl Atomizers

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2876
Author(s):  
Krystian Czernek ◽  
Michał Hyrycz ◽  
Andżelika Krupińska ◽  
Magdalena Matuszak ◽  
Marek Ochowiak ◽  
...  
Keyword(s):  
Literature Review ◽  
Droplet Diameter ◽  
Experimental Studies ◽  
Chemical Properties ◽  
Injection Pressure ◽  
Spray Angle ◽  
Atomization Process ◽  
Complex Process ◽  
Physico Chemical ◽  
Basic Features

This paper presents issues in the field of theory, construction, calculations, as well as the design of effervescent-swirl atomizers. The results of experimental studies of spraying liquids with different physico-chemical properties for this type of atomizers are discussed. Effervescent-swirl atomization is a complex process and its mechanism is not fully understood. Therefore, the purpose of the manuscript is the complexity of the atomization process and its mechanism as well as the influence of individual parameters on its efficiency were thoroughly analyzed. The analyzed parameters include: atomizer design, outlet shape, gas and liquid flow rate, injection pressure, physicochemical properties of the atomized liquid, pressure drop, outflow coefficient, spray angle, quantitative droplet distributions, and average droplet diameter. Moreover, in the work, on the basis of the literature review, the results of the research related to, inter alia, the phenomenon of air core formation and the influence of a number of parameters on the efficiency of the atomization process are analyzed. The literature review included in the work makes it possible to better understand the atomization process carried out in effervescent-swirl atomizers, and also provides better design criteria and analysis of the efficiency of the tested devices. The article presents correlation equations covering the basic features of the atomization process, which relate a large number of parameters influencing the efficiency of this process and the character of the sprayed liquid, which may be useful in design practice.

Controls of Li incorporation in aragonite

2020 ◽  
Author(s):  
Vasileios Mavromatis ◽  
Jean-Michel Brazier ◽  
Katja Goetschl
Keyword(s):  
Growth Rate ◽  
Experimental Studies ◽  
Chemical Properties ◽  
Elemental Ratios ◽  
Mineral Growth ◽  
Chemical Signatures ◽  
Physico Chemical ◽  
Geological Past ◽  
Temperature Proxy ◽  
Li Content

<p>The cation-to-Ca ratio in natural carbonate minerals is routinely used by the geoscientific community in order to reveal information about the conditions occurred during mineral formation in the geological past. Environmental reconstruction, however, relies on our understanding on the mechanisms controlling mineral growth but also on the physico-chemical properties of cations. In this respect experimental studies and laboratory calibrations of elemental ratios in synthetic carbonates provide important insights on the interpretation of the chemical signatures in natural samples. This holds especially truth for the chemical and isotopic signals of carbonates forming in continental environments that are characterized by the absence of bio-induced precipitation, low concentration of solutes in the forming fluid and slow growth rates (e.g. speleothems). In this study, we examine the incorporation of Li in aragonite, owing to its use as a temperature proxy and its importance in paleo-weathering reconstruction. Our preliminary results suggest that aragonite growth rate is likely the most important parameter controlling Li content in the forming phase. This finding comes in excellent agreement with the recent study by Füger et al. (2019). In addition, the experimental work suggest that temperature is also affecting the distribution of Li in aragonite but to a lesser extent than growth rate. It is anticipated that once completed this work will provide the fundamental knowledge needed for adequate interpretation of Li partitioning in aragonite and significantly improve our ability to interpret Li signatures in natural carbonates.</p><p> </p><p>References: Füger et al. 2019. Effect of growth rate and pH on lithium incorporation in calcite, Geochim. Cosmochim. Acta., 248, 14-24.</p>

scholarly journals Physico-chemical properties and chromatographic findings of different natural solvent extracts of Vitex negundo Linn.

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Vivek Kumar ◽  
Harmeet Kaur ◽  
Galib R ◽  
Prajapathi P K
Keyword(s):  
Experimental Studies ◽  
Chemical Properties ◽  
Dosage Forms ◽  
Vitex Negundo ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Water As Solvent ◽  
Chemical Profiles

Introduction: Ayurveda, uses various herbs that are converted into different dosage forms mostly in presence of Jala (water) as solvent. In addition to water; seers also advocated certain other solvents for extraction of active principles from the herbs. Works on using traditional solvents other than water in extracting principles from different herbs are not reported till date. Aims: Considering lack of such evidences, an attempt has been made to prepare Nirgundi Ghana (solid extract of Vitex negundo Linn.) in three different solvents i.e. Jala (water), Kanji (sour gruel) and Gomutra (cow’s urine) and analyze respective physico-chemical profiles. Materials and Methods:  Ghana was prepared by classical methods described in Ayurveda. The samples were analyzed through relevant physico-chemical parameters. Results: In pharmaceutical study; yield was found more in presence of Kanji and Gomutra. Physico-chemical profiles showed few differences, but in most of the cases, they were insignificant. Conclusion: Based on preliminary physico-chemical profiles, it cannot be ascertained the usefulness of the finished products in therapeutics. Relevant experimental studies to identify and characterize the active phyto-constituents and evaluate therapeutic utilities of the principles extracted into the respective solvents are essential in further studies. 

Decoration of specific sites on freeze-fractured membranes

1978 ◽  
Vol 36 (2) ◽  
pp. 140-141
Author(s):  
H. Gross ◽  
H. Moor
Keyword(s):  
Pure Water ◽  
Freeze Fracture ◽  
Chemical Properties ◽  
Surface Forces ◽  
Sulfate Pentahydrate ◽  
Copper Sulfate Pentahydrate ◽  
Physico Chemical ◽  
Water Of Hydration ◽  
Small Container ◽  
Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

Physico-Chemical Properties of Recombinant Desulphatohirudin

1990 ◽  
Vol 63 (03) ◽  
pp. 499-504 ◽  
Author(s):  
A Electricwala ◽  
L Irons ◽  
R Wait ◽  
R J G Carr ◽  
R J Ling ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Chemical Properties ◽  
Alpha Helix ◽  
Apparent Molecular Weight ◽  
Correlation Spectroscopy ◽  
Nmr Studies ◽  
Recombinant Hirudin ◽  
Physico Chemical ◽  
Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

Physico-chemical properties of the rare-earth metals, scandium, and yttrium

1963 ◽  
Vol 79 (2) ◽  
pp. 263-293 ◽  
Author(s):  
E.M. Savitskii ◽  
V.F. Terekhova ◽  
O.P. Naumkin
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Chemical Properties ◽  
Physico Chemical ◽  
The Rare Earth

Physico chemical properties and gas adsorption separation characteristics of Itaya zeolite and its modified products.

1990 ◽  
Vol 39 (442) ◽  
pp. 996-1000 ◽  
Author(s):  
Ayao TAKASAKA ◽  
Hideyuki NEMOTO ◽  
Hirohiko KONO ◽  
Yoshihiro MATSUDA
Keyword(s):  
Gas Adsorption ◽  
Chemical Properties ◽  
Physico Chemical
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