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The Composite materials are widely acceptable and they are indispensible. The design synthesize and characterize of the new material under wet condition is something special. In particularly, the material used for aesthetic decoration applications. Light weight low strength applications are very wide. This investigation focuses the natural fiber hybrid with artificial fiber based hybrid composite preparation. The banana fiber is used to prepare the composite with textile-grade glass fibers. The banana fiber is here treated with specific concentration of 2-Hydroxysuccinic Acid in the distilled water. The composites synthesized with treated and untreated banana fibers. The alternate fashion of horizontal and vertical is followed for fibers’ orientation. The bio epoxy is employed as matrix material with mix of hardener. The prepared composite are characterized by water absorbability and also characterized by tensile properties, flexural properties and shock absorption capacities in wet condition.

Iran is a country with a variety of different climates. Determining the threshold temperatures suitable for providing thermal and climatic comfort is necessary and vital to its population well-being. This research presents new threshold temperatures in order to calculate the degree day index required for heating and cooling by taking advantage of the 12 stations that are representative of the diversity of Iran's climate. Using Olgyay diagram, different bioclimatic ranges of 12 weather stations and their frequencies were compiled, processes and analysed. Mean daily data of temperature and relative humidity were used for the period of 1950–2010. Based on the frequencies of temperature readings falling in Olgyay's diagram comfort zone, representive temperature thresholds were selected based on 40 to 60 percentiles or (P20), 25–75% percentile (P50) and the threshold of 10–90% percentile. The findings of this study shows that Mashhad with 29.6% and Anzali with 2.33% of frequencies, have experienced the maximum and minimum days of comfort. After analyzing various percentiles to determine the threshold temperatures, it was observed that there is a little difference among the stations for determining the minimum threshold for the comfort. Differences are more obvious in the maximum thresholds. In total, minimum base temperatures (HDD) belonged to Ardabil stations that were 20.50, 20.90 and 20 deg C for P20, P50 and P80 respectively. The maximum temperature for calculating CDD with values of (P20 = 25 °C; P50 = 26.25 °C; P80 = 27.50 °C) is dedicated to Zabol station. The findings present more reasonable thermal comfort thresholds that can be used by architects, engineers and policy makers to achieve, in turn, more energy efficient homes and high quality indoor and outdoor living environments.

Heat transfer characteristics of an anodized two-phase closed thermosyphon (TPCT) with refrigerant as the working fluid is studied and compared with that of a non-anodized one. A simple anodization is performed to make a porous structure on the inner wall of TPCT. The anodized and non-anodized TPCTs charged with a blend of R600a and R290 are tested for the heat input range of 50–200 W. The effects of filling ratio, inclination angle, heat input and anodized surface on the performance of the TPCTs are investigated. Due to the anodization, the evaporator heat transfer coefficient enhances up to 33% at the inclination angle of 45° for the heat input of 200 W. Also, total thermal resistance of the anodized TPCT is reduced by 17%, 20% and 23% respectively for horizontal, inclined and vertical positions when compared to the non-anodized TPCT. Enhancements in the surface area, number of nucleation sites, increased bubble frequency, intensified bubble interaction and thin film evaporation are major factors for the performance enhancement in the anodized TPCT. Also it is found that the filling ratio, inclination angle and heat input have a significant role on the performance of the TPCT.

The purpose of this research is to simulate the impact of climate changes on the need for energy consumption in household cooling and heating systems using degree-day index. To this end, general circulation model has been applied to identify future climate changes and simulate degree-day values. The research findings show an increase of energy consumption for cooling in households in 2075. Also, with warm seasons prolonging and cold seasons shrinking in a year, the need for the continuous supply of energy consumption for air cooling and ventilation increases.

Bio-inspired microstructured surfaces have been developed that attach effectively to a wet surface. However, little is known about the associated tribological and adhesion properties involved. In this paper, the adhesion of a microstructured surface to peritoneal tissue is investigated as a function of preload, speeds of approach and angle of tilt to the horizontal. Results show that within a critical range of preload and speed of approach of the microstructured surface to the tissue result in good adhesion characteristics at the micro-structured surface/tissue interface. The microstructured surface adhesion to the tissue and the payload supported against gravity depend significantly on the tilt angle to the horizontal. Furthermore, a wet adhesion model was used to elucidate the adhesion mechanism of the microstructured surface to a wetted glass. These tests provide significant initial data for the design of a miniature mobile intra-abdominal device which drives the need for this adhesion study.

There is an abundance of clinical applications using human umbilical cord blood (HUCB) as a source for stem cell populations. Other than haematopoietic progenitors, there are mesenchymal, endothelial stem cells and neuronal precursors, in varying quantities, that are found in human umbilical cord blood. These may be useful in diseases such as immune deficiency and autoimmune disorders. Considering issues of safety, availability, transplant methodology, rejection and side effects, it is contended that a therapeutic stem cell transplant, utilizing stem cells from HUCB, provides a reliable repository of early precursor cells that can be useful in a great number of diverse conditions. Drawbacks of relatively smaller quantities of mononucleated cells in one unit of cord blood can be mitigated by in-vitro expansion procedures, improved in-vivo signalling, and augmentation of the cellular milieu, while simultaneously choosing the appropriate transplantation site and technique for introduction of the stem cell graft.

he distribution of electron current in GaAs AlGaAs v-groove quantum wire structures with groove widths varying from 1 to 25 mum has been studied using far- and near-field spectroscopy techniques. We find clear evidence of the formation of 'corner' quantum wires in wide grooves which coalesce to form single wires in grooves with widths narrower than similar to 5 mum. Spatially resolved photoluminescence measurements in the presence of an applied voltage provide information about the distribution of current in the device. (C) 2002 Elsevier Science B.V. All rights reserved.

Single GaAs v-groove quantum wire structures, of varying width, have been studied using near-field and far-field photoluminescence (PL) and photoluminescence excitation (PLE) techniques. Strong non-thermal behaviour has been observed in complex quasi-1D/2D systems at temperatures below 40 K. Spatially resolved PL measurements in the presence of an applied voltage provide information about the distribution of current in the grooves. We find evidence of real-space transfer of carriers at higher voltages. (C) 2002 Elsevier Science B.V. All rights reserved.

The nature and the concentration of the second component of a binary palladium alloy affects its catalytic activity in hydrogen addition and subtraction reactions with organic compounds. Hydrogen permeation across a palladium alloy catalyst enhances the rate and selectivity of hydrogenation compared with what is observed when the compound being hydrogenated is mixed directly with hydrogen. The principal product of diene hydrogenation when the hydrogen permeates through a membrane catalyst is not a saturated hydrocarbon but the corresponding olefin from which polymers can be synthesized. The rate of hydrogen atom addition to the diene molecules on the palladium alloy surface is higher than the rate of hydrogen atom recombination and desorption in the form of hydrogen molecules.

The surface state of an active membrane has a marked effect on its hydrogen permeability and catalytic activity in reactions involving the addition or subtraction of hydrogen. Interactions of organic compounds, oxygen and hydrogen on membrane catalysts produce changes in their surface composition and structure such that the rates of catalytic reactions and hydrogen transfer are altered and carbon migrates into the membrane bulk. Polishing and chemical cleaning of the membrane surface increases the rate of hydrogen transfer through the membrane. Membranes with a porous surface display catalytic activity and hydrogen permeability which are an order of magnitude higher than those of the initial foils.