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41.
Dmitri?A.?RozmanovEmail author Yury?V.?Sidorov Kim?A.?Burkov 《Journal of solution chemistry》2005,34(9):1081-1090
The volume change of the forced hydrolysis of the beryllium cation has been investigated by dilatometry and potentiometry
methods. An equilibrium scheme has been proposed and the volume effects of the individual stages have been determined relative
to the volume change of the neutralization reaction. It has been shown that the hydrolytic polymerization of the beryllium
cation leads to a decrease of the solution volume compared with the neutralization reaction. Such behavior is a unique feature
of the beryllium cation. 相似文献
42.
Application of temperature modulated dilatometry (TM DIL) to investigation on degradation of the adhesion between ceramic
films and the substrate is presented. Layers of titanium nitride deposited by plasma assisted physical vapour deposition (PA
PVD) methods on the Armco iron substrates were tested. This paper shows that the TM DIL method is helpful in determining the
usefulness of the titanium nitride covering of the cutting tools and machine parts.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
43.
P. J. Sánchez-Soto A. Ruiz-Conde R. Bono M. Raigón E. Garzón 《Journal of Thermal Analysis and Calorimetry》2007,90(1):133-141
The thermal evolution of a slate rock sample (Berja, Almería, Spain) has been studied. The phase minerals identified in this
sample were mica (illite), chlorite (clinochlore) and quartz as major components, with minor microcline, iron oxide and a
mixed-layer or interstratified phase (montmorillonite-chlorite). This slate is highly silico-aluminous (48.33 mass% silica,
22.04 mass% alumina), and ca. 20 mass% of other elements, mainly Fe2O3 (8.35 mass%), alkaline-earths and alkaline oxides.
Two main endothermic DTA effects, centered at 640 and 730°C, were observed. The more important contribution of total mass
loss (7.15 mass%) was found between 500–900°C, with two DTG peaks detected at 630 and 725°C. All these effects were associated
to the dehydroxylation of structural OH groups of 2:1 layered silicates mixed in the slate. The dehydroxylation of the layered
silicates evidenced by dilatometry, produced a rapid increase of expansion between 600–800°C. The thermal evolution of the
slate upper 800°C indicated the first sintering effects associated to shrinkage, which is also favoured by its low particle
size (average 23 μm) and the presence of a liquid or vitreous phase as increasing the heating temperature. The application
of thermal diffractometry to the slate sample allowed to study the formation of dehydroxylated crystalline phases from the
layered silicates after heating. At 1000°C, β-quartz, dehydroxylated illite, iron oxide, relicts of microcline and the vitreous
phase were present in the sample. All these results are interesting to know the thermal behaviour of a complex mineral mixture
as identified in the slate. 相似文献
44.
The aim of the present work is to find relation between the state of ceramic coating of iron and the physical properties of
coated samples as a function of temperature. The iron samples coated by plasma assisted physical vapor deposition (PA PVD)
with layers of TiN were investigated with new technique – temperature modulated thermomagnetometry (TM TMAG) and thermal dilatometry
(TM DIL). From the irregular behavior of the thermal dilatation and magnetic susceptibility, the process of the coating degradation
can be resolved.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
45.
ABSTRACT Inconsistencies exist in literature regarding the effect of prior austenite grain size (PAGS) on the extent and kinetics of bainite transformation. Attempts have been made in the present work to address these issues in a low-alloy carbide-free bainitic steel using dilatometry, over a range of PAGS. The bainite transformation kinetics in the above-mentioned conditions have been analysed quantitatively using established kinetic model to extract information related to the transformation mechanisms in such conditions. Greater obstruction from grain boundaries in fine-grained austenite restricts sheaves of bainite to develop completely and thereby reduces the volume fraction of bainite in comparison with coarse-grained austenite. Initial nucleation rate of bainite transformation increases with decreasing PAGS due to an increase in the nucleation site density. However, the maximum nucleation rate decreases consistently with decreasing PAGS due to gradual reduction in the autocatalytic factor. 相似文献
46.
Pressure‐volume‐temperature and glass transition behavior of silica/polystyrene nanocomposite 下载免费PDF全文
The pressure‐volume‐temperature (PVT) behavior and glass transition behavior of a 10 wt % silica nanoparticle‐filled polystyrene (PS) nanocomposite sample are measured using a custom‐built pressurizable dilatometer. The PVT data are fitted to the Tait equation in both liquid and glassy states; the coefficient of thermal expansion α, bulk modulus K, and thermal pressure coefficient γ are examined as a function of pressure and compared to the values of neat PS. The glass transition temperature (Tg) is reported as a function of pressure, and the limiting fictive temperature (Tf′) from calorimetric measurements is reported as a function of cooling rate. Comparison with data for neat PS indicates that the nanocomposite has a slightly higher Tg at elevated pressures, higher bulk moduli at all pressures studied, and its relaxation dynamics are more sensitive to volume. The results for the glassy γ values suggest that thermal residual stresses would not be reduced for the nanocomposite sample studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1131–1138 相似文献
47.
Thermal, mechanical and thermomagnetic properties associated with the magnetic and structural transition of an amorphous Fe80Cr5B15 alloy are described. The investigation was carried out in a simultaneous dilatometric and thermomagnetic experiment. An anomaly
of the thermal expansion coefficient at the Curie point and a change in mechanical properties just before the onset of crystallization
are observed. The results are compared with the thermal behavior obtained by differential scanning calorimetry. 相似文献
48.
Reinhard Schwdiauer Johannes Heitz Enno Arenholz Simona BauerGogonea Siegfried Bauer Werner Wirges 《Journal of Polymer Science.Polymer Physics》1999,37(16):2115-2125
Glass‐like and structural first‐order phase transitions are investigated in polytetrafluoroethylene (PTFE) foils and PTFE‐like films prepared by pulsed‐laser deposition (PLD) and plasma polymerization (PP). A structural comparison of the investigated polymers is performed by infrared spectroscopy and dielectric dilatometry. It is shown that dielectric dilatometry (the measurement of the susceptance vs. temperature) provides a simple and elegant means for detecting volumetric transitions in thin nonpolar polymer films. In conventional PTFE foils, the known glass‐like and structural first‐order phase transitions are identified. The structure of pulsed‐laser deposited PTFE strongly depends on the target material, ranging from highly crystalline films showing only structural phase transitions to films strongly deviating from PTFE foils, with structural characteristics comparable to plasma‐polymerized fluorocarbons. The dielectric loss of the highly crystalline PLD films compares favorably with conventional PTFE foils, making the films attractive for new applications in miniature electret devices. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2115–2125, 1999 相似文献
49.
Thermal differential diagnosis of mica mineral group 总被引:1,自引:0,他引:1
The following criteria can be used for differential diagnosis of mica mineral group: weight loss < 350°C; weight loss during dehydroxylation (500–1000°C); peak temperature of structural decomposition and formation of high temperature phases; course of dilatometric curves during dehydroxylation and structural decomposition interval (Fig. 1).Using the single criteria by stepwise comparing a complete thermal differentiation is possible between the members of mica mineral group.Dedicated to Dr. Robert Mackenzie on the occasion of his 75th birthday 相似文献
50.
F. R. Sale 《Journal of Thermal Analysis and Calorimetry》1994,42(4):793-810
Control of processing parameters, in both conventional ceramic routes and novel gel processing routes, is vital in the production of electronic and magnetic ceramics. The role of thermal analysis in the provision of basic data for the understanding of both types of processing route is discussed with special emphasis being placed upon the production of 1–2–3 YBCO superconductors and MgO-based soft ferrite materials for TV deflection unit applications. 相似文献