Volumetric and acoustic properties of binary systems (furfural or furfuryl alcohol+toluene) and (furfuryl alcohol+ethanol) at different temperatures

2015 ◽  
Vol 611 ◽  
pp. 47-55 ◽  
Author(s):  
M. Zaoui-Djelloul-Daouadji ◽  
L. Bendiaf ◽  
I. Bahadur ◽  
A. Negadi ◽  
D. Ramjugernath ◽  
...  
Keyword(s):  
Furfuryl Alcohol ◽  
Binary Systems ◽  
Acoustic Properties ◽  
Different Temperatures

scholarly journals Fano resonance based defected 1D phononic crystal for highly sensitive gas sensing applications

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Shrouk E. Zaki ◽  
Ahmed Mehaney ◽  
Hekmat M. Hassanein ◽  
Arafa H. Aly
Keyword(s):  
Band Gap ◽  
Gas Sensor ◽  
Fano Resonance ◽  
Figure Of Merit ◽  
Phononic Crystal ◽  
Acoustic Properties ◽  
Effect Of Temperature ◽  
Sensing Applications ◽  
Damping Rate ◽  
Different Temperatures

Abstract The defected acoustic band gap materials are promising a new generation of sensing technology based on layered cavities. We introduced a novel 1D defected phononic crystal (1D-DPC) as a high-sensitive gas sensor based on the Fano resonance transmitted window. Our designed (Lead–Epoxy) 1D-DPC multilayer has filled with a defect layer with different gases at different temperatures. In this study, Fano resonance—based acoustic band gap engineering has used to detect several gases such as O2, CO2, NH3, and CH4. For the first time, Fano resonance peaks appeared in the proposed gas sensor structures which attributed to high sensitivity, Q-factor, and figure-of-merit values for all gases. Also, the relation between the Fano resonance frequency and acoustic properties of gases at different temperatures has been studied in detail. The effect of the damping rate on the sensitivity of the gas sensor shows a linear behavior for CO2, O2, and NH3. Further, we introduced the effect of temperature on the damping rate of the incident waves inside the 1D-DPC gas sensor. The highest sensitivity and figure of merit were obtained for O2 of 292 MHz/(kg/m3) and 647 m3/Kg, respectively. While the highest figure-of-merit value of 60 °C−1 at 30 °C was attributed to O2. The transfer matrix method is used for calculating the transmission coefficient of the incident acoustic wave. We believe that the proposed sensor can be experimentally implemented.

scholarly journals High Temperature Structure in Cool Binary Stars

1996 ◽  
Vol 152 ◽  
pp. 141-145
Author(s):  
A.K. Dupree ◽  
N.S. Brickhouse ◽  
G.J. Hanson
Keyword(s):  
High Temperature ◽  
Binary Stars ◽  
Binary Systems ◽  
Emission Measure ◽  
Temperature Structure ◽  
Differential Emission Measure ◽  
Absolute Size ◽  
Hot Plasma ◽  
Short Period ◽  
Different Temperatures

Strong high temperature emission lines in the EUVE spectra of binary stars containing cool components (Alpha Aur [Capella], 44ι Boo, Lambda And, and VY Ari) provide the basis to define reliably the differential emission measure of hot plasma. The emission measure distributions for the short-period (P ≤ 13 d) binary systems show a high temperature enhancement over a relatively narrow temperature region similar to that originally found in Capella (Dupree et al. 1993). The emission measure distributions of rapidly rotating single stars 31 Com and AB Dor also contain a local enhancement of the emission measure although at different temperatures and width from Capella, suggesting that the enhancement in these objects may be characteristic of rapid rotation of a stellar corona. This feature might be identified with a (polar) active region, although its density and absolute size are unknown; in the binaries Capella and VY Ari, the feature is narrow and it may arise from an interaction region between the components.

Viscosity and surface tension of binary systems of N,N-dimethylformamide with alkan-1-ols at different temperatures

2013 ◽  
Vol 56 ◽  
pp. 106-113 ◽  
Author(s):  
Abubaker A. Mohammad ◽  
Khaled H.A.E. Alkhaldi ◽  
Mohammad S. AlTuwaim ◽  
Adel S. Al-Jimaz
Keyword(s):  
Surface Tension ◽  
Binary Systems ◽  
Different Temperatures

scholarly journals Densities, Viscosities and Excess Properties for Dimethyl Sulfoxide with Diethylene Glycol and Methyldiethanolamine at Different Temperatures

2021 ◽  
Vol 12 (1) ◽  
pp. 116
Author(s):  
Maria Magdalena Budeanu ◽  
Vasile Dumitrescu
Keyword(s):  
Molar Volume ◽  
Diethylene Glycol ◽  
Atmospheric Pressure ◽  
Binary Systems ◽  
Partial Molar Volumes ◽  
Excess Properties ◽  
Excess Functions ◽  
Viscosity Deviation ◽  
Different Temperatures ◽  
Experimental Density

Densities and viscosities of the binary systems dimethylsulfoxide with diethylene glycol and methyldiethanolamine were measured at temperatures ranging from 293.15 to 313.15 K, at atmospheric pressure and over the entire composition range. The experimental density data was correlated as a function of composition using Belda’s and Herraez’s equations, and as a function of temperature and composition using the models of Emmerling et al. and Gonzalez-Olmos-Iglesias. The viscosity results were fitted to the Grunberg-Nissan, Heric-Brewer, Wilson, Noda, and Ishida and Eyring-NRTL equations. The values of viscosity deviation (), excess molar volume (VE), partial molar volumes ( and ) and apparent molar volume ( and ) were determined. The excess functions of the binary systems were fitted to the polynomial equations. The values of thermodynamic functions of activation of viscous flow were calculated and discussed.

scholarly journals Thermo-physical properties and activity coefficients at infinite dilution for ionic liquid systems at several temperatures

2017 ◽  
Author(s):  
◽  
Sangeeta Singh
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Thermodynamic Properties ◽  
Infinite Dilution ◽  
Binary Systems ◽  
Isentropic Compressibility ◽  
Liquid Systems ◽  
Different Temperatures ◽  
Kister Equation ◽  
Deviation In Isentropic Compressibility

The thermodynamic properties of mixtures involving ionic liquids (ILs) with organic acid (acetic acid or propanoic acid) or acetonitrile at different temperatures were determined. The ILs used were imidazolium-based: 1-ethyl-3-methylimidazolium ethyl sulphate [EMIM]+[EtSO4]-, 1-butyl- 3-methylimidazolium thiocyanate [BMIM]+[SCN]- and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ([BMIM]+[Tf2N]-. The ternary excess molar volume (V E ), isentropic compressibility (ks) and deviation in isentropic compressibility ( ks123 ) were determined for four ternary liquid mixtures of {[EMIM]+[EtSO4]- or [BMIM]+[SCN]− + acetic or propionic acid + acetonitrile} at different temperatures (293.15, 298.15, 303.15, 308.15 and 313.15) K and at a pressure of 0.1 MPa with aid of the experimental density (ρ), speed of sound (u) data. The calculated data were correlated by using the Cibulka equation with the help of Redlich–Kister parameters obtained from fitting the Redlich–Kister equation for the corresponding binary systems. Furthermore, the density and speed of sound were also measured for eight corresponding binary systems at the same experimental conditions. The binary excess molar volume, isentropic compressibility and deviation in isentropic compressibility were also calculated for measured systems and fitted to the Redlich–Kister equation to obtain the Redlich–Kister parameters as well as to check the accuracy of measured data which were used to correlated experimental data using Cibulka equation. These results were discussed, in terms of how the sign and magnitude of thermodynamic functions were influenced by the addition of a third component to liquid systems. Also, the possible molecular and pair-wise interactions between component molecules and the effect of temperature on the thermophysical and thermodynamic properties were predicted. In addition, the work focussed on application of ([BMIM]+[Tf2N]-) ionic liquid for the separations of (alkane/aromatic), (alkane/alk-1-ene), (cycloalkane/aromatic) and (water/alkan-1-ol) using gas- liquid chromatography (GLC) technique. The activity coefficients at infinite dilution, , for 31 organic solutes (alkanes, cycloalkanes, alkenes, alkynes, aromatics, alkanol and ketones) and water in ionic liquid were measured at temperatures of (323.15, 333.15, 343.15, 353.15 and 363.15) K. Stationary phase loadings of (42.83 and 68.66) % by mass were used to ensure repeatability of E , measurements. Partial molar excess enthalpies at infinite dilution, H1 , were also determined. The selectivities, S , and capacities, k , were determined for the above separations. The separating ij j ability of the investigated ionic liquid was compared with previously investigated ionic liquids and industrial solvents such as sulfolane, n-methyl-2-pyrrolidine (NMP) and n-formylmorpholine (NFM). The results obtained suggested that in general, the [BMIM]+[Tf2N]− had outperformed the conventional solvents such as sulfolane, NMP and NFM in terms of selectivity, while the [BMIM][Tf2N] had in general, performed better overall when the performance index was used for comparison.

scholarly journals Shelf-Life Evaluation and Lyophilization of PBCA-Based Polymeric Microbubbles

Pharmaceutics ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 433 ◽  
Author(s):  
Tarun Ojha ◽  
Vertika Pathak ◽  
Natascha Drude ◽  
Marek Weiler ◽  
Dirk Rommel ◽  
...  
Keyword(s):  
Shelf Life ◽  
Rhodamine B ◽  
Freeze Drying ◽  
Pharmaceutical Products ◽  
Acoustic Properties ◽  
Signal Generation ◽  
Freeze Dried ◽  
Different Temperatures ◽  
The Stability ◽  
Commercial Platform

Poly(n-butyl cyanoacrylate) microbubbles (PBCA-MB) are extensively employed for functional and molecular ultrasound (US) imaging, as well as for US-mediated drug delivery. To facilitate the use of PBCA-MB as a commercial platform for biomedical applications, it is important to systematically study and improve their stability and shelf-life. In this context, lyophilization (freeze drying) is widely used to increase shelf-life and promote product development. Here, we set out to analyze the stability of standard and rhodamine-B loaded PBCA-MB at three different temperatures (4 °C, 25 °C, and 37 °C), for a period of time of up to 20 weeks. In addition, using sucrose, glucose, polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG) as cryoprotectants, we investigated if PBCA-MB can be lyophilized without affecting their size, concentration, US signal generation properties, and dye retention. Stability assessment showed that PBCA-MB remain largely intact for three and four weeks at 4 °C and 25 °C, respectively, while they disintegrate within one to two weeks at 37 °C, thereby compromising their acoustic properties. Lyophilization analyses demonstrated that PBCA-MB can be efficiently freeze-dried with 5% sucrose and 5% PVP, without changing their size, concentration, and US signal generation properties. Experiments involving rhodamine-B loaded MB indicated that significant dye leakage from the polymeric shell takes place within two to four weeks in case of non-lyophilized PBCA-MB. Lyophilization of rhodamine-loaded PBCA-MB with sucrose and PVP showed that the presence of the dye does not affect the efficiency of freeze-drying, and that the dye is efficiently retained upon MB lyophilization. These findings contribute to the development of PBCA-MB as pharmaceutical products for preclinical and clinical applications.

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