To design equipment and facilities to dry, preserve and process pomegranates, it is necessary to know their specific heat and thermal CONDUCTIVITY. The objectives of this study were to determine the specific heat and thermal CONDUCTIVITY of pomegranates and develop mathematical estimation models for them. The effects of moisture content (15-75% w.b.) and temperature (5-20oC) on the thermal properties of pomegranates (Alak variety) were studied. Specific heat was measured using the mixtures method. The thermal CONDUCTIVITY was measured using a line heat source probe for pomegranate exocarps and mesocarps and the bare-wire transient method for the seeds. The results showed that an increase in moisture content and temperature produced a linear increase in the specific heat from 1.127 to 2.789 kJ/kgoC for seeds, 0.931 to 3.066 kJ/kgoC for mesocarps, and 1.516 to 3.411 kJ/kgoC for exocarps. Thermal CONDUCTIVITY increased from 0.1524 to 0.4218 W/m°C for seeds, 0.148 to 0.451 W/moC for mesocarps and 0.131 to 0.4204 W/moC for exocarps as moisture content and temperature increased. However, the effect of moisture content was greater than the effect of temperature on specific heat and thermal CONDUCTIVITY. The empirical equations for these thermal properties were subsequently expressed as a function of moisture content and temperature.

Low transmission of heat is one of the major problems for heat exchanger fluids in many industrial and scientific applications. This includes cooling of the engines, high power transformers to heat exchangers in solar hot water panels or in refrigeration systems. In order to tackle these problems in thermal industries, nanofluids could play a significant role as excellent heat exchanger materials for thermal applications. Silver nanofluids can be used abundantly for thermal applications due to their low cost and high thermal CONDUCTIVITY. The present article describes the green synthesis of the silver nanoparticles from AgNO3 powder using some plant product like tannic acid. The silver nanoparticles are characterized by XRD, UV-visible spectrophotometer, TEM. The silver nanofluids of different concentrations are prepared by means of water as the base fluid. The ultrasonic velocity is calculated for different concentration at room temperature. Acoustical parameters like compressibility, intermolecular free length and acoustic impedance are calculated using ultrasonic velocity, density and viscosity and the results are discussed in terms of intermolecular interactions between the nanoparticles and the base fluid. The variation of ultrasonic velocity and other calculated acoustic parameters are used to analyze in amplification of heat CONDUCTIVITY of silver nanofluids.

The temperature of water entering the soil or variation in soil temperature has a direct impact on soil hydraulic CONDUCTIVITY via the effect on water viscosity. In this research, the time variability of soil saturated hydraulic CONDUCTIVITY (Ks) was studied. The relation between soil temperature and fluid viscosity with hydraulic CONDUCTIVITY were also studied. The necessary experiments were conducted on Aboureyhan campus research farm located in Pakdasht, 25 km southeast of Tehran. 18 holes were digged in a plot and saturated hydraulic CONDUCTIVITY of soils were measured in these holes using inverse hole method. Experiments were carried out 12 times from 16- Aug- 2005 to 14- Jun- 2006. Investigations showed that the lowest value of Ks was obtained in winter when the soil and air temperatures are at minimum and by increasing the soil and air temperatures, these values increased too. Statistical analysis of experiments indicated that soil or air temperatures can considerably affect the results. Using the average of measured Ks to design drainage systems showed that neglecting the time variability of Ks may result in over or underestimating of drain spacing by 18.9% and 23.3%, respectively. Using the average of Ks values which was obtained in soil temperature of 16- 20 oC had least effect on drain spacing, so it can be used as an average Ks to design drain spacing.

(CuCl)4-2x-(KCl)x– CdCl2, x = 0. 0– 0. 4 solid electrolytes were grown via solid-state reaction procedure by suitable heattreatment. An AC impedance spectroscopy suggested that the ionic CONDUCTIVITY mainly arisen from grain effect. A DCelectrical CONDUCTIVITY of 3. 94 9 10-5 Scm-1 was measured for the x = 0. 3 composition at 320  C. This also shows lowestactivation energy in the temperature range of 293– 593 K. This has been explained by that fact that at high temperaturesthermal disturbances through lattice vibrations take place. In such a high-temperature region, Cu? readily jumps andmigrates at short range, but the number of mutual collisions also increases resulting in a decrease of the Cu? mobility. Thepresent study reveals that the change in CONDUCTIVITY value depends on concentration of doped ingredient as well as onvarious parameters in the system. Therefore, these solid electrolytes will be suitable for the development of differentelectrochemical applications.

In the current research, thermal CONDUCTIVITY of magnetite (Fe3O4) has been calculated using molecular dynamic simulation. The rNEMD Molecular Dynamics Method provided in the LMMPS package is used for the simulation of the thermal CONDUCTIVITY. The effects of magnetite layer size and temperature on the thermal CONDUCTIVITY have been investigated. The numerical results have been validated by experimental data. Results show that the thermal CONDUCTIVITY of magnetite can be predicted appropriately using Buckingham potential function. Moreover, Thermal CONDUCTIVITY of magnetite is shown to be a decreasing function of temperature. The obtained results provide a benchmark for magnetite ferrofluid heat transfer simulations, which has been extensively increased in recent years.

The present research work was aimed at developing conductive polymer-based composites in order to have a higher CONDUCTIVITY than the standard level of the Energy Institute of America. In this case, the composites can be applied to make electrodes. For this purpose, carbon clack particles, carbon nanotube and expanded graphite with different weight percentages (5%, 10%, 15%, 25%, and 35%) were added to the epoxy resin and the electrical CONDUCTIVITY of the samples was measured according to the four-point standard method. The average electrical CONDUCTIVITY threshold for carbon clack particles, carbon nanotube and expanded graphite was determined at 25, 10, and 15, respectively. Furthermore, the effect of different construction parameters such as the use of vacuum pumps and heating on the electrical CONDUCTIVITY of the composite samples was also investigated. The experiments revealed that the use of the vacuum pump increased the electrical CONDUCTIVITY by 10. 8%, 11. 4% and 9. 6% in carbon black, carbon nanotube, and expanded graphite samples, respectively. In order to increase the mechanical strength of the conductive polymer samples, ten layers of unidirectional carbon fabric were used. The results obtained showed that the use of carbon fibers enhanced the electrical CONDUCTIVITY by 23. 2%, 27. 3%, and 24. 7% for carbon black, expanded graphite, and carbon nanotube samples, respectively. Ultimately, using the scanned electron microscopy images, the quality of the nanoparticle distribution in the samples was investigated.

Hydraulic CONDUCTIVITY is one of the soil"s dynamic properties, which plays a major role in water flow and salts transport within the soil. A saturated hydraulic CONDUCTIVITY value is needed for drainage projects design, which is almost constant. Different methods can be used in determining insitu hydraulic CONDUCTIVITY and they can be divided into two groups, e.g. above and below water table methods. Preliminary investigations showed that there was a significant difference between the results of these methods. The objectives of this study were 1) to investigate and compare the hydraulic CONDUCTIVITY values obtained using the above-mentioned methods in Iran and other countries; 2) to find the reasons of differences between the results of these two methods; and 3) to present practical solutions to minimize these differences. Generally, the results obtained by the above water table method were lower than those of under water table one. Based on the results of this research, values of under water table method were 0.5 to 32 times bigger than those of the above water table method. The reason for such a difference can be explained by various factors, e.g. water quality, the collapse of well walls, trapped air bubbles within soil pore, and the difference in flow patterns. Lower values obtained by the above water table method compare with under water table one may indicate that the saturated hydraulic CONDUCTIVITY cannot be accurately determined using the above water table method. Therefore, the results of this kind of method need to be closer to those of under water table one. In this regard, the suitable methods can be ranked as following: Natural model method, field model method, geostatitical method, Macnill method and correlation between texture and structure method.