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Abstract  

Changes in the thermal conductivities of paraffin and mono ethylene glycol (MEG) as a function of β-SiC nanoparticle concentration and size was studied. An enhancement in the effective thermal conductivity was found for both fluids (i.e., both paraffin and MEG) upon the addition of nanoparticles. Although an enhancement in thermal conductivity was found, the degree of enhancement depended on the nanoparticle concentration in a complex way. An increase in particle-to-particle interactions is thought to be the cause of the enhancement. However, the enhancement became muted at higher particle concentrations compared to lower ones. This phenomenon can be related to nanoparticles interactions. An improvement in the thermal conductivities for both fluids was also found as the nanoparticle size shrank. It is believed that the larger Brownian motion for smaller particles causes more particle-to-particle interactions, which, in turn, improves the thermal conductivity. The role that the base-fluid plays in the enhancement is complex. Lower fluid viscosities are believed to contribute to greater enhancement, but a second effect, the interaction of the fluid with the nanoparticle surface, can be even more important. Nanoparticle-liquid suspensions generate a shell of organized liquid molecules on the particle surface. These organized molecules more efficiently transmit energy, via phonons, to the bulk of the fluid. The efficient energy transmission results in enhanced thermal conductivity. The experimentally measured thermal conductivities of the suspensions were compared to a variety of models. None of the models proved to adequately predict the thermal conductivities of the nanoparticle suspensions.

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Abstract  

The application of particle acclerators in industrial research is reviewed. An R and D mechanism of nuclear analytical research is suggested to illustrate the driving force that doubles in a couple of years the number of publications almost in every branch of nuclear analytical methods. After a general discussion of particle interactions, the various methods of activation analysis and prompt nuclear methods and their applications are shown.

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Abstract  

Self-irradiation effects due to -radiation in plutonium/IV/ hydroxo phenyl acetate, Pu/OH/3/C6H5CH2COO/ and hydroxo -naphthyl acetate, Pu/OH/3/C10H7CH2COO/ have been studied by EPR technique. OH and C6H5CH2COO. species are identified in the phenyl acetate while the C10H7CH2COO. species is detected in -naphthyl acetate. The values of the efficiency parameter, , determined for OH, C6H5CH2COO. and C10H7CH2COO. species are 0.8, 1.31 and 2.18, respectively. The results are interpreted on the basis of the thermal spikes associated with the alpha particle interaction with the lattice.

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A lot of attention is being paid to the understanding of the influence of soil degradation on human life at the beginning of the 21 st century. Among the many types of degradation processes, structural degradation is widespread on huge areas in Europe. For better control, it is needed to get familiar with all the driving forces, the main reasons that lead to soil degradation (Várallyay, 2003; ESB, 2002). In addition to unfavourable natural conditions, inappropriate land use has an important impact on micro-aggregate stability and the rate of tolerance to deformation forces, such as cultivation and erosion.  Rheological measurements provide new quantitative information on particle-particle interaction, the colloidal stability and structure of concentrated suspensions in general. Field samples from loess derived agricultural soils were investigated. In addition to general laboratory analyses (soil organic matter content, CaCO 3 content, CEC), conventional, simple aggregate stability, and water retention measurements and rheology were applied for investigating the micro-aggregate stability of the samples. The evaluation of pseudoplastic flow curves indicated close relationships between the strength and stability of the physical network and the composition of the suspensions. These soil properties have strong, well-defined connection with tolerating cultivation and capability for erosion. 

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temperature ( T gp ) at 8 wt% (beyond 6 wt%) of CdS nano-particles in PMMA is caused due to the change in dispersion of nano-particles from uniform to clustering, which is also confirmed by TEM images. This clustering enhances the particle–particle interaction

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3048 – 3065 . [30]. B. Oesterlé A. Petitjean 1993 Simulation of particle-to-particle

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The analysis of hardening of metal materials

Structural level of deformation and parameters of thermomechanical treatment

Journal of Thermal Analysis and Calorimetry
Authors: Slobodan Stojadinovic, Jasmina Pekez, and Nikola Bajic

deformed, (strained), crystal lattice of basis, because of the soluted atoms of alloyed elements. Complex heterogeneous alloys, that can boost, in other words strengthen also on account of: interaction of dislocation and dispersion particles, interaction of

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Journal of Thermal Analysis and Calorimetry
Authors: N. Ivashchenko, V. Tertykh, V. Yanishpolskii, J. Skubiszewska-Zięba, R. Leboda, and S. Khainakov

for the palladium face-centered cubic lattice [ 24 ]. It can be assumed from the TEM images that the nature of surface layer strongly affects the size of formed metal particles. Interaction of palladium nitrate solution with TES-modified silica

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Rheology of nanocomposites

Modelling and interpretation of nanofiller influence

Journal of Thermal Analysis and Calorimetry
Authors: Christophe Block, Nick Watzeels, Hubert Rahier, Bruno Van Mele, and Guy Van Assche

to quantify via a single parameter the solid-like behaviour of the nanofiller network. Adding well-dispersed nanofiller to the matrix is also likely to alter the rheological behaviour of the polymer close to the filler particles due to matrix–particle

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a neat PP. b 20 wt%. c 45 wt%. d 60 wt% FA composites Fig. 5 A proposed physical scheme of polymer chain and FA particle interaction in a 20 wt%. b 45 wt

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