Extension of the DSC method to measuring vapor pressures of narrow boiling range oil cuts

2015 ◽  
Vol 622 ◽  
pp. 31-37 ◽  
Author(s):  
Carmen Siitsman ◽  
Vahur Oja
Keyword(s):  
Vapor Pressures ◽  
Boiling Range ◽  
Dsc Method ◽  
Narrow Boiling Range

Thermodynamics of porphyrin sublimation

2000 ◽  
Vol 04 (08) ◽  
pp. 699-706 ◽  
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.

scholarly journals Estimation of Properties of Narrow Boiling Range Coal-Derived Liquids from the 150 ton/day NEDOL Coal Liquefaction Pilot Plant.

2002 ◽  
Vol 81 (9) ◽  
pp. 854-863
Author(s):  
Hirohito ISHIBASHI ◽  
Minoru ONEYAMA ◽  
Takashi HAYASHI ◽  
Masatoshi KOBAYASHI ◽  
Jun-ichiro HAYASHI ◽  
...  
Keyword(s):  
Pilot Plant ◽  
Coal Liquefaction ◽  
Boiling Range ◽  
Narrow Boiling Range

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

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).

Differentiated Scanning Calorimetry of Model Systems with Cocoa Butter

Food Industry ◽  
2020 ◽  
Vol 5 (2) ◽  
pp. 29-36
Author(s):  
Alexander Vereshchagin ◽  
Irina Reznichenko ◽  
Nikolay Bychin
Keyword(s):  
Cocoa Butter ◽  
Palm Olein ◽  
Palm Stearin ◽  
Model Systems ◽  
Scanning Calorimetry ◽  
Glucose Syrup ◽  
Polymorphic Modifications ◽  
Confectionery Products ◽  
System Temperature ◽  
Dsc Method

The article concerns the research specificity of model systems such as cocoa butter – palm olein, cocoa butter – sucrose and cocoa butter – glucose syrup by the differential scanning calorimetry (DSC) method. The researchers run experiments in the temperature range from –100 to –50°C at a heating rate of 10 °C/min. In the cacao butter – palm olein system an eutectic occurs with a palm olein content of 30.0 % indicating the limited solubility of palm olein in cocoa butter. In the cocoa butter – sucrose system, cocoa butter crystallizes as in the α-form (10,0– 30,0; 60.0–90.0 % MK), and as a mixture of α-and β-forms of MK (40.0; 50,0; 70,0 and 80.0 %). Sucrose stabilizes low-temperature polymorphic modifications of cocoa butter. In the cocoa butter – glucose syrup system, temperature of samples melting is 21-22 °C. This composition is promising for use as a filling of confectionery products and glazes production. In this regard, a man can use glucose syrup only in the candy cases production. The role of surfactants used for the formation and stabilization of cocoa butter polymorphs and increasing the thermal stability of the shock-lad without the introduction of palm stearin requires separate consideration.

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