Model Vulcanization of EPDM Compounds—Part II: Influence of Temperature and Time on the Vulcanization Products from Ethylidene Norbornane

1984 ◽  
Vol 57 (4) ◽  
pp. 725-734 ◽  
Author(s):  
J. H. M. van den Berg ◽  
J. W. Beulen ◽  
J. M. H. Hacking ◽  
E. F. J. Duynstee
Keyword(s):  
Model Compound ◽  
Influence Of Temperature ◽  
Hplc Chromatogram

Abstract Influence of vulcanization temperature and time on the sulfur crosslinks in vulcanized EPDM (third monomer ENB) was studied using the low-moleular model compound ENBH (C9H14). For each vulcanization condition (60 min at 180°, 160°, 140°, and 120° and 60, 30, 15, and 5 min at 140°), the nature of the crosslinks is represented by the composition of the C9H13−Sn−C9H13 vulcanization mixture as indicated by its HPLC chromatogram. In this way it is shown that increase in temperature favors formation of disulfidic crosslinks at the expense of the higher-sulfide crosslinks. Under the mildest vulcanization conditions (60 min at 120° or 5 min at 140°), disulfidic crosslinks are nearly absent and penta-sulfidic crosslinks are the most important.

The effect of temperature on high-resolution TEM image contrast

1995 ◽  
Vol 53 ◽  
pp. 640-641
Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz
Keyword(s):  
Form Factor ◽  
Inelastic Scattering ◽  
Accurate Method ◽  
Waller Factor ◽  
Effect Of Temperature ◽  
Specimen Thickness ◽  
Influence Of Temperature ◽  
Debye Waller Factor ◽  
Influence Of Temperature On ◽  
Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

COMPUTER MODELING OF CHEMICAL EQUILIBRIUMS IN WO3–H2O SYSTEM

2017 ◽  
pp. 35-48 ◽  
Author(s):  
V.P. Bondarenko ◽  
O.O. Matviichuk
Keyword(s):  
Transition Temperature ◽  
Gas Phase ◽  
Single Phase ◽  
Reference Data ◽  
Maximum Amount ◽  
Reaction Products ◽  
Influence Of Temperature ◽  
Equilibrium Chemical ◽  
Program Data ◽  
Good Agreement

Detail investigation of equilibrium chemical reactions in WO3–H2O system using computer program FacktSage with the aim to establish influence of temperature and quantity of water on formation of compounds of H2WO4 and WO2(OH)2 as well as concomitant them compounds, evaporation products, decomposition and dissociation, that are contained in the program data base were carried out. Calculations in the temperature range from 100 to 3000 °С were carried out. The amount moles of water added to 1 mole of WO3 was varied from 0 to 27. It is found that the obtained data by the melting and evaporation temperatures of single-phase WO3 are in good agreement with the reference data and provide additionally detailed information on the composition of the gas phase. It was shown that under heating of 1 mole single-phase WO3 up to 3000 °С the predominant oxide that exist in gaseous phase is (WO3)2. Reactions of it formation from other oxides ((WO3)3 and (WO3)4) were proposed. It was established that compound H2WO4 is stable and it is decomposed on WO3 and H2O under 121 °C. Tungsten Oxide Hydrate WO2(OH)2 first appears under 400 °С and exists up to 3000 °С. Increasing quantity of Н2О in system leads to decreasing transition temperature of WO3 into both liquid and gaseous phases. It was established that adding to 1 mole WO3 26 mole H2O maximum amount (0,9044–0,9171 mole) WO2(OH)2 under temperatures 1400–1600 °С can be obtained, wherein the melting stage of WO3 is omitted. Obtained data also allowed to state that that from 121 till 400 °С WO3–Н2O the section in the О–W–H ternary system is partially quasi-binary because under these temperatures in the system only WO3 and Н2O are present. Under higher temperatures WO3–Н2O section becomes not quasi-binary since in the reaction products WO3 with Н2O except WO3 and Н2O, there are significant amounts of WO2(OH)2, (WO3)2, (WO3)3, (WO3)4 and a small amount of atoms and other compounds. Bibl. 12, Fig. 6, Tab. 5.

The Influence of Temperature on Successful Reproductions of Burbot, Lota Lota (L.) Under Hatchery Conditions

2010 ◽  
Vol 25 (1) ◽  
pp. 93-105 ◽  
Author(s):  
Daniel Żarski ◽  
Dariusz Kucharczyk ◽  
Wojciech Sasinowski ◽  
Katarzyna Targońska ◽  
Andrzej Mamcarz
Keyword(s):  
Lota Lota ◽  
Influence Of Temperature ◽  
Influence Of Temperature On

The influence of temperature and rainfall in the human viral infections

2019 ◽  
Vol 1 (1) ◽  
pp. 12-20
Author(s):  
L.R.R. Vidal ◽  
L.A. Pereira ◽  
M.C. Debur ◽  
S.M. Raboni ◽  
M.B. Nogueira ◽  
...  
Keyword(s):  
Viral Infections ◽  
Influence Of Temperature
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