ChemInform Abstract: Vapor Pressure of Benzene. Part 2. Saturated Vapor Pressures from 279 to 300 K.

The saturated vapor pressures of R22 uniformly mixed with refrigeration oil and nano- refrigeration-oil were measured experimentally at a temperature range from 263 to 333K and mass fractions from 1 to 5%. The experimental results showed that the saturated vapor pressure of R22/KT56 mixture was lower than that of pure R22; the pressure deviation between them increased with a raising mass fraction of refrigeration oil and temperature. After adding nano-NiFe2O4 and nano-fullerene into KT56, the pressure deviation increased at the same mass fraction and temperature. A saturated vapor pressure correlation for R22 and refrigeration oil/nano-refrigeration-oil mixture was proposed, and the calculated values agreed with the experimental data within the deviation of ± 0.77%.

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Thermodynamics of porphyrin sublimation

Journal of Porphyrins and Phthalocyanines ◽

10.1002/1099-1409(200012)4:8<699::aid-jpp284>3.0.co;2-m ◽

2000 ◽

Vol 04 (08) ◽

pp. 699-706 ◽

Cited By ~ 18

Author(s):

GERMAN L. PERLOVICH ◽

OLEG A. GOLUBCHIKOV ◽

MARIJA E. KLUEVA

Keyword(s):

Crystal Structure ◽

Vapor Pressure ◽

Thermodynamic Functions ◽

Gas Flow ◽

Thermal Destruction ◽

Saturated Vapor ◽

Inert Gas ◽

Sublimation Enthalpy ◽

Vapor Pressures ◽

Dsc Method

The saturated vapor pressures of tetraphenylporphyrin H 2 TPP , its four-coordinated metallo-complexes MTPP ( M ≡ Ni , Cu , Zn , Pd , Ag , Cd ) and some phenyl-substituted derivatives H 2 T ( R ) PP ( R ≡ 2-, 3-, 4- CH 3; 2-, 4- F ; 2-, 3-, 4- Cl ; 3-, 4- Br ; 3,5- C ( CH 3)3) have been measured using the inert gas flow method. The values of sublimation enthalpy Δ sub H m and entropy Δ sub S m are calculated. On the basis of the kinetic vapor pressure dependence, the start temperatures of thermal destruction of the investigated porphyrins are determined. The temperatures of melting of the tetraphenylporphyrin metallo-complexes measured by the DSC method are in linear correlation with the Δ sub H m values. The correlation between the thermodynamic functions of porphyrin sublimation (Δ sub H m , Δ sub S m , Δ sub G m ) and the literature data on the crystal structure of the compounds is considered. The Δ sub H m values obtained by some authors by different methods are compared with the results of our investigations. Possible reasons for discrepancies in the results are discussed.

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Direct Measurements of Vapor Pressures of Chlorinated Paraffin Congeners from Technical Mixtures

10.26434/chemrxiv.14350481.v1 ◽

2021 ◽

Author(s):

Jort Hammer ◽

Hidenori Matsukami ◽

Hidetoshi Kuramochi ◽

Satoshi Endo

Keyword(s):

Vapor Pressure ◽

Environmental Fate ◽

Saturated Vapor ◽

Chemical Properties ◽

Carbon Chain ◽

Carbon Chain Length ◽

Vapor Pressures ◽

Direct Measurements ◽

Chlorinated Paraffins ◽

Saturation Method

Chlorinated Paraffins (CPs) are a complex group of manmade chemicals detected widely in the environment. To predict their environmental fate and effects, it is important to understand their physical-chemical properties including vapor pressure. In this study, the first direct measurements of the vapor pressure for CP congener groups (C10–16Cl4–11) are presented. Vapor pressure was measured above three industrial CP mixtures with different congener distributions between 20 and 50°C using a gas saturation method. The measured saturated vapor pressure (P*) decreased with increasing carbon chain length and Cl content. ΔHvap ranged between 73 and 122 kJ mol-1, consistent with data from the literature and model prediction. The experimental log P* at 25°C agreed well with predictions from an empirical regression model in the literature (R2 = 0.97; RSME = 0.25) and with those predicted from the COSMO-RS-trained fragment contribution model (R2 = 0.95; RSME = 0.35). A new empirical model was calibrated with the P* data for 35 congener groups measured in this study. Predicted log P* values correlate well with field-measured gas/particle partition coefficients and may therefore be used for estimating the environmental fate and pathways of a broad range of CPs in the environment.

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Direct Measurements of Vapor Pressures of Chlorinated Paraffin Congeners from Technical Mixtures

10.26434/chemrxiv.14350481 ◽

2021 ◽

Author(s):

Jort Hammer ◽

Hidenori Matsukami ◽

Hidetoshi Kuramochi ◽

Satoshi Endo

Keyword(s):

Vapor Pressure ◽

Environmental Fate ◽

Saturated Vapor ◽

Chemical Properties ◽

Carbon Chain ◽

Carbon Chain Length ◽

Vapor Pressures ◽

Direct Measurements ◽

Chlorinated Paraffins ◽

Saturation Method

Chlorinated Paraffins (CPs) are a complex group of manmade chemicals detected widely in the environment. To predict their environmental fate and effects, it is important to understand their physical-chemical properties including vapor pressure. In this study, the first direct measurements of the vapor pressure for CP congener groups (C10–16Cl4–11) are presented. Vapor pressure was measured above three industrial CP mixtures with different congener distributions between 20 and 50°C using a gas saturation method. The measured saturated vapor pressure (P*) decreased with increasing carbon chain length and Cl content. ΔHvap ranged between 73 and 122 kJ mol-1, consistent with data from the literature and model prediction. The experimental log P* at 25°C agreed well with predictions from an empirical regression model in the literature (R2 = 0.97; RSME = 0.25) and with those predicted from the COSMO-RS-trained fragment contribution model (R2 = 0.95; RSME = 0.35). A new empirical model was calibrated with the P* data for 35 congener groups measured in this study. Predicted log P* values correlate well with field-measured gas/particle partition coefficients and may therefore be used for estimating the environmental fate and pathways of a broad range of CPs in the environment.

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Scanning electron microscopy of plant cells using a variable-pressure SEM and cryogenic techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147144 ◽

1993 ◽

Vol 51 ◽

pp. 260-261

Author(s):

M. Yamada ◽

K. Ueda ◽

K. Kuboki ◽

H. Matsushima ◽

S. Joens

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Saturated Vapor ◽

Plant Cells ◽

Variable Pressure ◽

Specimen Preparation ◽

Operating Pressure ◽

Vapor Pressures ◽

Low Temperature Microscopy ◽

Scanning Electron

Use of variable Pressure SEMs is spreading among electron microscopists The variable Pressure SEM does not necessarily require specimen Preparation such as fixation, dehydration, coating, etc which have been required for conventional scanning electron microscopy. The variable Pressure SEM allows operating Pressure of 1˜270 Pa in specimen chamber It does not allow microscopy of water-containing specimens under a saturated vapor Pressure of water. Therefore, it may cause shrink or deformation of water-containing soft specimens such as plant cells due to evaporation of water. A solution to this Problem is to lower the specimen temperature and maintain saturated vapor Pressures of water at low as shown in Fig. 1 On this technique, there is a Published report of experiment to have sufficient signal to noise ratio for scondary electron imaging at a relatively long working distance using an environmental SEM. We report here a new low temperature microscopy of soft Plant cells using a variable Pressure SEM (Hitachi S-225ON).

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Effects of nanoparticles on hydraulic cavitation

MATEC Web of Conferences ◽

10.1051/matecconf/201824003004 ◽

2018 ◽

Vol 240 ◽

pp. 03004

Author(s):

Min-rui Chen ◽

Jin-yuan Qian ◽

Zan Wu ◽

Chen Yang ◽

Zhi-jiang Jin ◽

...

Keyword(s):

Vapor Pressure ◽

Saturated Vapor Pressure ◽

Saturated Vapor ◽

Geometric Model ◽

Pressure Ratio ◽

Perforated Plate ◽

Significant Parameter ◽

Operation Conditions ◽

Small Bubbles ◽

Crucial Condition

When liquids flowing through a throttling element, such as a perforated plate, the velocity increases and the pressure decreases. If the pressure is below the saturated vapor pressure, the liquid will vaporize into small bubbles, which is called hydraulic cavitation. In fact, vaporization nucleus is another crucial condition for vaporizing. The nanoparticles contained in the nanofluids play a significant role in vaporization of liquids. In this paper, the effects of the nanoparticles on hydraulic cavitation are investigated. Firstly, a geometric model of a pipe channel equipped with a perforated plate is established. Then with different nanoparticle volume fractions and diameters, the nanofluids flowing through the channel is numerically simulated based on a validated numerical method. The operation conditions, such as the temperature and the pressure ratio of inlet to outlet, are the considered variables. As a significant parameter, cavitation numbers under different operation conditions are achieved to investigate the effects of nanoparticles on hydraulic cavitation. Meanwhile, the contours are extracted to research the distribution of bubbles for further investigation. This study is of interests for researchers working on hydraulic cavitation or nanofluids.

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Volatility of Antioxidants and Antiozonants. 1. Pure Compounds in Absence of Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3540304 ◽

1964 ◽

Vol 37 (1) ◽

pp. 210-220 ◽

Cited By ~ 18

Author(s):

R. B. Spacht ◽

W. S. Hollingshead ◽

H. L. Bullard ◽

D. C. Wills

Keyword(s):

Vapor Pressure ◽

Aromatic Amine ◽

Quantitative Data ◽

Surface Effects ◽

Vapor Pressures ◽

Pure Compounds ◽

Different Temperatures ◽

Amine Compounds

Abstract Comparable volatility data are presented for three phenolic and five aromatic amine compounds. Vapor pressure curves for the materials are given along with the vapor pressure equations derived from these curves. The equations are used to calculate temperatures at which the eight compounds would have equal vapor pressure. Vapor pressures of each material are calculated at specified temperatures. Data are given for several methods of determining actual losses of antioxidants at several different temperatures and at several different airflows. Surface effects are also studied. In general, all methods give the same relative rating of the eight materials, but quantitative data vary considerably with the method used.

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Density Determination of Cryogenic Liquids as a Function of Saturated Vapor Pressure

Advances in Cryogenic Engineering ◽

10.1007/978-1-4757-0528-7_30 ◽

1963 ◽

pp. 251-255 ◽

Cited By ~ 1

Author(s):

T. C. Shupert

Keyword(s):

Vapor Pressure ◽

Saturated Vapor Pressure ◽

Saturated Vapor ◽

Density Determination ◽

Cryogenic Liquids

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Porous Hydroxyapatite with Tailored Crystal Surface Prepared by Hydrothermal Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.284-286.353 ◽

2005 ◽

Vol 284-286 ◽

pp. 353-356 ◽

Cited By ~ 1

Author(s):

Koji Ioku ◽

Giichiro Kawachi ◽

Nakamichi Yamasaki ◽

Hirotaka Fujimori ◽

Seishi Goto

Keyword(s):

Aspect Ratio ◽

Vapor Pressure ◽

Hydrothermal Method ◽

Saturated Vapor Pressure ◽

Crystal Surface ◽

Saturated Vapor ◽

Pure Water ◽

Porous Hydroxyapatite ◽

Exposure Method ◽

The Mean

Porous plates of hydroxyapatite (Ca10(PO4)6(OH)2; HA) with about 0.5 to 5 mm in thickness and porous HA granules of about 40 µm to 1 mm in size with tailored crystal surface were prepared by the hydrothermal vapor exposure method at the temperatures above 105 °C under saturated vapor pressure of pure water. Porous HA plates with about 75 % porosity prepared at 120 °C were composed of rod-shaped crystals of about 20 µm in length. Porous HA granules prepared at 160 °C were also composed of rod-shaped crystals of about 20 µm in length with the mean aspect ratio of 30. These crystals were elongated along the c-axis. Rod-shaped HA crystals were locked together to make micro-pores of about 0.1 to 0.5 µm in size. Both of materials were nonstoichiometric HA with calcium deficient composition. These materials must have the advantage of adsorptive activity, because they had large specific crystal surface and much micro-pores.

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