Thermodynamic parameters of butan-1-ol at atmospheric pressure

The solubility of isatin in different solvents was studied by a gravimetrical method from (298.15 to 318.15) K under atmospheric pressure and the solubility data were correlated against temperature. The solvents selected for the present study are: water, methanol, ethanol, 1-butanol, dichloromethane, dichloroethane, chloroform and carbon tetra chloride. Among chlorinated solvents, solubility is observed to be maximum in 1, 2-dichloroethane and minimum in dichloromethane whereas in alcohols, maximum solubility is observed in methanol. In water, solubility is found to be minimum. Further, some thermodynamic parameters such as Gibb’s energy (ΔGsol), heat of solution (ΔHsol) and entropy of solution (ΔSsol) have also been evaluated.

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2D-model of glow discharge plasma in the atmospheric pressure helium formed after spark breakdown: calculating electrophysical and thermodynamic parameters

Izvestiya vysshikh uchebnykh zavedenii. Fizika ◽

10.17223/00213411/62/10/129 ◽

2019 ◽

pp. 129-136

Author(s):

V.P. Demkin ◽

◽

S.V. Melnichuk ◽

A.V. Postnikov

Keyword(s):

Glow Discharge ◽

Thermodynamic Parameters ◽

Atmospheric Pressure ◽

Discharge Plasma ◽

Glow Discharge Plasma ◽

Spark Breakdown ◽

2D Model

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EFFECT OF PRESSURE ON EXCESS THERMODYNAMIC CHARACTERISTICS OF WATER + FORMAMIDE MIXTURE

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.20165906.5363k ◽

2018 ◽

Vol 59 (6) ◽

pp. 28

Author(s):

Gennadiy I. Egorov ◽

Dmitriy M. Makarov ◽

Arkadiy M. Kolker

Keyword(s):

Experimental Data ◽

Hydrogen Bonds ◽

Gibbs Energy ◽

Thermodynamic Parameters ◽

Atmospheric Pressure ◽

Thermodynamic Characteristics ◽

Molar Gibbs Energy ◽

Molar Entropy ◽

Mixing Enthalpies ◽

Entropy Component

Using the experimental data on the densities at atmospheric pressure and compressibility coefficients, k=(Vo-V)/Vo, of water + FA mixture the changes in the following thermodynamic parameters were calculated under the pressure increase up to 100 MPa within the temperature range from 288.15 to 323.15 K: excess molar Gibbs energy, ΔPo→PGmE, excess molar entropy ,ΔPo→PSmE, and excess molar entropy ΔPo→PHmE. It was established that ΔPo→PGmEvalues were negative over the whole concentration range and minima appeared on ΔPo→PGmE= f(x2) functions at x2≈0.33. The pressure growth up to 100 MPa resulted in ΔPo→PGmE absolute values increase within entire concentration and temperature intervals. The changes in entropy component, -(ΔPo→PTSmE), of ΔPo→PGmEvalues were almost canceled by the enthalpy component changes. Minimal values of ΔPo→PSmE corresponded to x2≈ 0.33, exactly at that composition 2Н2О-FA associate formed. The isobaric temperature lowering caused the structure ordering also at x2≈ 0.33. The pressure growth promoted the increasing in exothermicity of the mixing enthalpies, HmE, of water and formamide. The changes in HmE value under the mixture compression are indicative of the larger exothermal contribution from new H-bonds formation as compared with the endothermic contribution from the decreasing in the total amount of hydrogen bonds. The temperature lowering decreases ΔPo→PHmEvalues as well; maximal isotherms dispersion is observed at concentrations corresponding to maximal content of 2:1 or 1:1 associates of water and FA.

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Models of Thermodynamic Properties of Prominences

International Astronomical Union Colloquium ◽

10.1017/s0252921100065799 ◽

1979 ◽

Vol 44 ◽

pp. 349-355

Author(s):

R.W. Milkey

Keyword(s):

Thermodynamic Properties ◽

Mass Transport ◽

Emission Spectrum ◽

Thermodynamic Parameters ◽

Working Group ◽

Physical Processes ◽

Theoretical Concepts ◽

Group 3 ◽

Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

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A High-Voltage Terminal for a Field-Emission Gun

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009539x ◽

1972 ◽

Vol 30 ◽

pp. 428-429

Author(s):

N. F. Ziegler

Keyword(s):

Field Emission ◽

High Voltage ◽

Atmospheric Pressure ◽

Power Supplies ◽

High Coherence

A high-voltage terminal has been constructed for housing the various power supplies and metering circuits required by the field-emission gun (described elsewhere in these Proceedings) for the high-coherence microscope. The terminal is cylindrical in shape having a diameter of 14 inches and a length of 24 inches. It is completely enclosed by an aluminum housing filled with Freon-12 gas at essentially atmospheric pressure. The potential of the terminal relative to ground is, of course, equal to the accelerating potential of the microscope, which in the present case, is 150 kilovolts maximum.

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Electron microscope characterization of MOCVD-grown gap layers on Si

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144991 ◽

1986 ◽

Vol 44 ◽

pp. 724-725

Author(s):

K.M. Jones ◽

M.M. Al-Jassim ◽

J.M. Olson

Keyword(s):

Atmospheric Pressure ◽

Vapour Deposition ◽

Chemical Vapour ◽

Organic Chemical ◽

Lattice Match ◽

Si Substrates ◽

Metal Organic ◽

Good Lattice ◽

Antiphase Domains

The epitaxial growth of III-V semiconductors on Si for integrated optoelectronic applications is currently of great interest. GaP, with a lattice constant close to that of Si, is an attractive buffer between Si and, for example, GaAsP. In spite of the good lattice match, the growth of device quality GaP on Si is not without difficulty. The formation of antiphase domains, the difficulty in cleaning the Si substrates prior to growth, and the poor layer morphology are some of the problems encountered. In this work, the structural perfection of GaP layers was investigated as a function of several process variables including growth rate and temperature, and Si substrate orientation. The GaP layers were grown in an atmospheric pressure metal organic chemical vapour deposition (MOCVD) system using trimethylgallium and phosphine in H2. The Si substrates orientations used were (100), 2° off (100) towards (110), (111) and (211).

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Microstructure and reactivity of small metal particles: The role of Ce additives

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121995 ◽

1992 ◽

Vol 50 (1) ◽

pp. 318-319

Author(s):

L.D. Schmidt ◽

K. R. Krause ◽

J. M. Schwartz ◽

X. Chu

Keyword(s):

Atmospheric Pressure ◽

Noble Metals ◽

Mixed Oxides ◽

Catalytic Properties ◽

Chemical Shifts ◽

Catalytic Converter ◽

Structural Evolution ◽

Single Particles ◽

Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

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