Expanded Chlorinated Rubber

1937 ◽  
Vol 10 (4) ◽  
pp. 798-800
Author(s):  
P. Schidrowitz ◽  
C. A. Redfarn
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Electrical Properties ◽  
Electric Heating ◽  
Research Association ◽  
British Patent ◽  
Rubber Material ◽  
Insulating Material ◽  
Thermal And Electrical Properties ◽  
Aluminum Plates

Abstract In a previous publication (J. Soc. Chem. Ind., 54, 263T–267T (1935); Rubber Chem. and Tech., 8, 613 (1935)) some particulars were given regarding the production and development of a hard spongy material from chlorinated rubber (British Patent No. 424,561). Thermal and Electrical Properties Some preliminary tests on the thermal and electrical properties of the material have now been carried out, and these serve to confirm the view that expanded chlorinated rubber should prove to be a very good insulating material. Thermal Conductivity.—The details given herewith are taken from a report by the Research Association of British Rubber Manufacturers. The thermal conductivity was determined by comparison with cork, a good insulating material of which the thermal properties are fairly well known. The method used consisted in placing slabs of cellular rubber and of cork each between a pair of aluminum plates, and then interposing between the two sets of plates an electric heating plate made of wire enclosed between sheets of mica. The plates, heater, and sheets of expanded chlorinated rubber material and cork were all of the same size, namely, 20.3 by 10.25 cm. The aluminum plates were 0.625 cm. thick.

Thermal Diffusivity and Conductivity of La0.7Ca0.3-xSrxMnO3 (x=0 to 0.10)

2012 ◽  
Vol 501 ◽  
pp. 319-323
Author(s):  
Hasan A. Alwi ◽  
Lay S. Ewe ◽  
Zahari Ibrahim ◽  
Noor B. Ibrahim ◽  
Roslan Abd-Shukor
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Grain Size ◽  
Transition Temperature ◽  
Thermal Diffusivity ◽  
Electrical Properties ◽  
Room Temperature ◽  
Electronic Contribution ◽  
Insulator Metal Transition ◽  
Thermal And Electrical Properties

We report the room temperature thermal conductivity κ and thermal diffusivity α of polycrystalline La0.7Ca0.3-xSrxMnO3 for x = 0 to 0.1. The samples were prepared by heating at 1220 and 1320oC. The insulator-metal transition temperature, TIM and thermal diffusivity increased with Sr content. Phonon was the dominant contributor to thermal conductivity and the electronic contribution was less than 1%. Enhancement of electrical conductivity σ and thermal diffusivity for x ≥ 0.08 was observed in both series of samples. The grain size of the samples (28 to 46 µm) does not show any affect on the thermal and electrical properties.

scholarly journals Determination of thermal properties of some ceiling material commonly used in Ijebu- Ode, Nigeria

2020 ◽  
Vol 9 (1) ◽  
pp. 23-27
Author(s):  
J.O. Adepitan ◽  
F.O. Ogunsanwo ◽  
J.D. Ayanda ◽  
A.A. Okusanya ◽  
A.D. Adelaja ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Tropical Rainforest ◽  
Building Construction ◽  
Thermal Resistivity ◽  
Electrical Method ◽  
Insulating Materials ◽  
Insulating Material ◽  
Range Of Values

The study investigates the thermal properties of different insulating material used in building construction in Ijebu Ode, a tropical rainforest region, south western, Nigeria. Five insulating material; asbestos, Plaster of Paris (P.O.P), PolyVinyl Chloride (PVC), hardboard and paperboard, were subjected to thermal investigation using Lee’s disc electrical method. The result obtained showed that the thermal conductivities obtained are within the range of values specified for good insulating materials. Asbestos was found to be associated with the least thermal conductivity of the value 𝟎. 𝟏𝟕𝟏𝟕 𝑾𝒎-𝟏𝑲-𝟏while PVC had the highest thermal conductivity values of 𝟏. 𝟔𝟒𝟗𝟗 𝑾𝒎-𝟏𝑲-𝟏. This may be associated with the temperature and the heat flux on the surface of the material. The results obtained for thermal conductivity, thermal resistivity and thermal diffusivity correlated favourably when compared with those of previous work from other locations. Asbestos being the material with the lowest thermal conductivity is therefore recommended for use as the suitable insulating ceiling material in the study area. Keywords: thermal conductivity, diffusivity, resistivity, Lee’s disc

Thermal Annealing Effect on the Thermal and Electrical Properties of Organic Semiconductor Thin Films

MRS Advances ◽  
2016 ◽  
Vol 1 (22) ◽  
pp. 1637-1643 ◽  
Author(s):  
Xinyu Wang ◽  
Boyu Peng ◽  
Paddy Chan
Keyword(s):  
Thermal Conductivity ◽  
Electrical Properties ◽  
Thermal Annealing ◽  
Organic Semiconductor ◽  
Field Effect ◽  
Annealing Temperature ◽  
Waste Heat ◽  
Annealing Effect ◽  
Field Effect Mobility ◽  
Thermal And Electrical Properties

ABSTRACTThe thermal and electrical properties of organic semiconductor are playing critical roles in the device applications especially on the devices with large area. Although the effect may be minor in a single device like field effect transistors, the unwanted waste heat would cause much more severe problems in large-scale devices as the power density will go up significantly. The waste heat would lead to performance degradation or even failure of the devices, and thus a more detailed study on the thermal conductivity and carrier mobility of the organic thin film would be beneficial to predict the limits of the device or design a thermally stable device. Here we explore the thermal annealing effect on the thermal and electrical properties of the small molecule organic semiconductor, dinaphtho[2,3-b:2’,3’-f]thieno[3,2-b]thiophene (DNTT). After the post deposition thermal annealing, the grain size of the film increases and in-plane crystallinity improves while cross-plane crystallinity keeps relatively constant. We demonstrated the cross-plane thermal conductivity is independent of the thermal annealing temperature and high annealing temperature will reduce the space-charge-limited current (SCLC) mobility. When the annealing temperature increase from 24 °C to 140 °C, the field effect mobility shows a gradual increase while the threshold voltage shifts from positive to negative. The different dependence of the SCLC mobility and field effect mobility on the annealing temperature suggest the improvement of the film crystallinity after thermal annealing is not the only dominating effect. Our investigation provides the constructive information to tune the thermal and electrical properties of organic semiconductors.

Thermal and Electrical Properties of Polypropylene/Carbon Nanotube Composites

2011 ◽  
Vol 299-300 ◽  
pp. 802-805
Author(s):  
Jing Long Gao ◽  
Yan Hui Liu
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Properties ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Degradation Rate ◽  
Volume Resistivity ◽  
Xrd Pattern ◽  
Nanotube Composites ◽  
Thermal And Electrical Properties ◽  
Carbon Nanotube Composites

In this work, the carbon nanotubes(CNTs) were reinforced with polypropylene(PP)matrix resins to improve the electrical and thermal properties of PP/ CNTs composites in different contents of 0,1, 3,and 5 wt.%. The surface, volume resistivity and crystallization type of the composites were investigated. As a result, the maximum degradation rate temperature of the composite is improved 30 °C, the surface resistivity and volume resistivity of composite are 5 ×106, 7 ×105,respectively, for the optimum composition of composite (CNTs 3 wt.%). The integrated XRD pattern of the composites shows the typical α-form PP crystals.

scholarly journals Critical Review on Nanofluids: Preparation, Characterization, and Applications

2016 ◽  
Vol 2016 ◽  
pp. 1-22 ◽  
Author(s):  
Mohamoud Jama ◽  
Tejvir Singh ◽  
Seifelislam Mahmoud Gamaleldin ◽  
Muammer Koc ◽  
Ayman Samara ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Thermal Properties ◽  
High Performance ◽  
Two Phase ◽  
Heat Transfer Fluids ◽  
Thermal And Electrical Properties ◽  
Improve Heat Transfer ◽  
The Stability ◽  
New Generation

Heat transfer fluids are a crucial parameter that affects the size and costs of heat exchangers. However, the available coolants like water and oils have low thermal conductivities, which put many limitations to the development of heat transfer to achieve high performance cooling. The need for development of new classes of fluids which enhance the heat transfer capabilities attracted the attention of many researchers. In the last few decades, modern nanotechnology developed nanoparticles, which have unique thermal and electrical properties that could help improve heat transfer using nanofluids. A “nanofluid” is a fluid with suspended fine nanoparticles which increases the heat transfer properties compared with the original fluid. Nanofluids are considered a new generation of heat transfer fluids and are considered two-phase fluids of liquid solid mixtures. The efficiency of the fluid could be improved by enhancing its thermal properties, especially the thermal conductivity, and it is expected that the nanofluids will have a greater thermal conductivity than the base fluids. This paper reviews the preparation of metallic and nonmetallic nanofluids along with the stability of the produced nanofluids. Physical and thermal properties as well as a range of applications are also discussed in detail.

Measurement of Thermal and Electrical Properties of Multiwalled Carbon Nanotubes–Water Nanofluid

2016 ◽  
Vol 138 (7) ◽  
Author(s):  
Abdullah Al-Sharafi ◽  
Ahmet Z. Sahin ◽  
Bekir S. Yilbas
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Properties ◽  
Electrical Properties ◽  
Water Mixture ◽  
Algebraic Equations ◽  
Multiwalled Carbon ◽  
Carrier Fluid ◽  
Particle Distributions ◽  
Thermal And Electrical Properties ◽  
Temperature Dependent Properties

The use of high conductive nanoparticles, such as carbon nanotubes (CNT), enhances the thermal and electrical conductivities of the carrier fluid. Depending upon the volumetric concentration of particles and their distribution in the carrier fluid, multifold enhancement of thermal and electrical properties is possible. Therefore, in the present study, thermal and electrical properties of CNT–water mixture are assessed at microscopic level. Special distribution of the CNT in water is obtained experimentally at microscale for different durations of the heating situation. Thermal and electrical properties are predicted numerically incorporating the particle distributions obtained from the experiment. The mass based analysis is also introduced to determine the thermal properties of the mixture. The findings are compared for those obtained from the simulations based on experimentally obtained micro-images. Algebraic equations are introduced to formulate the data obtained from the simulations for temperature dependent properties. It is demonstrated that the mass based estimation of thermal properties are significantly different than those obtained from the experimental based simulations because of the nonuniform particles distribution and their localized conductivity in the carrier fluid.

THERMAL AND ELECTRICAL PROPERTIES OF ARMCO IRON AT HIGH TEMPERATURES

1960 ◽  
Vol 38 (7) ◽  
pp. 887-907 ◽  
Author(s):  
M. J. Laubitz
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Thermal Expansion ◽  
Electrical Properties ◽  
High Temperatures ◽  
Curie Point ◽  
Armco Iron ◽  
Discontinuous Change ◽  
Thermal And Electrical Properties

Thermal and electrical conductivity, thermoelectric power vs. platinum, and thermal expansion of Armco iron were determined in the temperature range of 0 °C to 1000 °C. All these properties show a discontinuous change at the α–γ transition of iron, and a change in slope at the Curie point. These measurements were carried out as a contribution to a co-operative determination of thermal conductivity of Armco iron at high temperatures.

Role of multiwalled carbon nanotubes (MWCNTs) on rheological, thermal and electrical properties of PC/ABS blend

RSC Advances ◽  
2015 ◽  
Vol 5 (41) ◽  
pp. 32880-32890 ◽  
Author(s):  
Amir Rostami ◽  
Mohsen Masoomi ◽  
Mohammad Javad Fayazi ◽  
Mehdi Vahdati
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Properties ◽  
Electrical Properties ◽  
Multiwalled Carbon Nanotubes ◽  
Multiwalled Carbon ◽  
Thermal And Electrical Properties ◽  
Blend Nanocomposites

Investigation of MWCNTs localization and its impact on rheological, electrical, and thermal properties of PC/ABS(75/25)/MWCNTs blend nanocomposites.

Study of thermoelectric properties of InGaN/GaN superlattice

2011 ◽  
Vol 1329 ◽  
Author(s):  
Hung-Hsun Huang ◽  
Yuh-Renn Wu
Keyword(s):  
Thermal Conductivity ◽  
Electrical Properties ◽  
Figure Of Merit ◽  
Phonon Dispersion ◽  
Boltzmann Transport ◽  
Superlattice Structure ◽  
Operation Temperature ◽  
Relaxation Time Approximation ◽  
Thermal And Electrical Properties ◽  
Callaway Model

ABSTRACTAs many reports show that the superlattice structure could greatly enhance the figure of merit ZT value for the thermoelectric application. We studied the thermal and electrical properties of the InGaN/GaN superlattice structure, and further analyze the thermoelectric features with different superlattice period, doping concentration, and operation temperature. The elastic continuum model and Callaway model have been applied to calculate the phonon dispersion relation and the thermal conductivity, respectively. The electrical properties are obtained by the Boltzmann transport equation with the relaxation time approximation. Simulation results indicate that both the reduced thermal conductivity and enhanced power factor would have the contribution to the enhancement of the figure of merit ZT.

Water Absorption Effect on Syntactic Foam Thermal Insulation of a Flexible Pipe

2006 ◽  
Author(s):  
Alain Chalumeau ◽  
Antoine Felix-Henry
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Water Absorption ◽  
Thermal Insulation ◽  
Syntactic Foam ◽  
Full Scale ◽  
Flexible Pipe ◽  
Thermal Tests ◽  
Insulating Material ◽  
Water Absorption Effect

Thermal insulation of a flexible pipe for deepwater applications is generally obtained by spiraling syntactic foam extruded tapes around the pipe core, in between two thermoplastic sheaths. As water tightness of the insulating annulus can frequently not be guaranteed, water absorption and the effect on thermal properties of insulating material have to be determined, so as to be taken into account for Overall Heat Transfer Coefficient calculation of the flexible pipe. It is required to demonstrate the overall suitability of a specific insulating material for a given application. The first part of this paper describes accelerated fresh water absorption tests and subsequent thermal conductivity measurements, conducted on polypropylene syntactic foam filled with glass micro-spheres. Based on test data in the 50°C–100°C temperature range, a prediction model has been established to calculate water absorption for service life as long as 20 years. A relationship between thermal conductivity variation and water content has been demonstrated, so that thermal conductivity of material exposed to water can be calculated versus temperature and time of exposure, for design purpose. The second part describes the full scale thermal tests that have been performed by Technip, in order to compare the measured thermal properties and heat losses of the flexible pipes in vertical or horizontal positions, with the computer calculations. Finally, based on lab test ageing and full scale tests on non aged flexible pipe, Technip is able to predict the full thermal behaviour during all the lifetime of the pipe.

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