MARTENSITIC TRANSFORMATION AND THERMAL STABILITY IN Cu-Al-Co AND Cu-Al-Zr ALLOYS

Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCus martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.

The Characterization and Study of Physical Parameters of Ge Modified Se-Sn-Pb Chalcogenide System

In the present paper, we have studied the effect of Ge addition on the physical properties of Se-Sn-Pb chalcogenide ma- terial. The necessary physical parameters which have important role in determining the structure and strength of the material viz. constraints, coordination number etc. have been calculated. The increasing trend has been found in cohesive energy, heat of atomization and mean bond energy. The glass transition has been studied using the Tichy-Ticha and Lankhorst approaches, which also increases with the increasing Ge contents. The increase in these physical parameters is due to the increasing covalent character in the material.

Temperature and Magnetic Resonance Characteristics of Zinc, Manganese, Gadolinium, Gold, Iron Magnetic Nanoparticles and Cytokine Synergy in Hyperthermia

The temperature and magnetic moment depend-ence for assessing localized heating utilizing a new class of Manganese-Zinc-Gadolinium mag-netic nanoparticles was studied. These particles showed heating effect when subjected to alter-nating filed. Alternatively, a new approach was used to get disperse heating without spot heating by using the synthesis of particles at controlled Curie temperature of less than 44oC. The study reports a simple synthesis of Mn0.5Zn0.5GdxFe(2-x)O4 nanoparticles using chemical co- precipita-tion technique. The particles exhibited Curie temperature of 42篊 and high magnitude of mag-netic moments. The particles showed sigmoid behavior of dependence between temperature and magnetic moments. The Nuclear Magnetic Resonance spectroscopy showed T1 depend-ence on temperature in the range of 10-45篊. The particles may have high promise for self con-trolled magnetic hyperthermia application and its monitoring.

Temperature variations in the past 6000 years inferred from δ^(18)O of peat cellulose from Hongyuan,China

Trends of the temperature variations recorded in δ18O in Hongyuan peat cellulose are similar to those recorded in δ18O of Jinchuan peat cellulose and in δ18O of Dunde ice core. Climate events have been identified to be globally homogeneous. Two notable climate transition periods have been detected in the past 6000 years, namely 4000 aBP with climate shifting from cold to warm and 1500 aBP with climate shifting from warm to relatively cold. Power spectrum analysis was performed to investigate the periodical signals in the δ18O time series. Typical periodicities of 1200-1087 a, 752 a, 444 a, 325 a, 213 a, 127-123 a, 88 a, 79 a were discovered, indicating an integrated influence on Hongyuan climate from solar, monsoon and ocean activities. Solar forcing has been addressed to be the main driving forcing of Hongyuan climate.

Spatio-temporal snowmelt variability across the headwaters of the Southern Rocky Mountains

Understanding the rate of snowmelt helps inform how water stored as snow will transform into streamflow. Data from 87 snow telemetry （SNOTEL） stations across the Southern Rocky Mountains were used to estimate spatio-temporal melt factors. Decreases in snow water equivalent were correlated to temperature at these monitoring stations for eight half-month periods from early March through late June. Time explained 70% of the variance in the computed snow melt factors. A residual linear correlation model was used to explain subsequent spatial variability. Longitude, slope, and land cover type explained further variance. For evergreen trees, canopy density was relevant to find enhanced melt rates; while for all other land cover types, denoted as non- evergreen, lower melt rates were found at high elevation, high latitude and north facing slopes, denoting that in cold environments melting is less effective than in milder sites. A change in the temperature sensor about mid-way through the time series （1990 to 2013） created a discontinuity in the temperature dataset. An adjustment to the time series yield larger computed melt factors.

Mathematical Modeling of Heat Transfer Processes of Coal Waste Combustion in a Chamber of Automated Energy Generating Complex

The automated energy generating complex allows obtaining heat energy from waste coal-water slurry fuel （WCF） that is a mixture of fine coal particles from coal enrichment wastes with water. The mixture is blown into the swirl chamber under the pressure through the special sprayers. The received heat energy is used in different ways. One of the important issues is to estimate the heat losses through the walls of this chamber. In this paper we solved the boundary problem of mathematical physics to estimate the temperature fields in the walls of the swirl chamber. The obtained solution allows us to estimate the heat losses through the waUs of the swid chamber. The task of the mathematical physics has been solved by a numerical finite-difference method. The method for solving this prob- lem can be used in the calculation of temperature fields and evaluation of heat losses in other thermal power units.

Comparison of thermal performance between test cells with different coverage systems for experimental typical day of heat in Brazilian Southeastern

This article shows experimentally the thermal performance of two test cells with different coverage systems, Ught Green Roof （LGR） and ceramic roof by analyzing internal surface temperatures （IST） in the ceiling and dry bulb temperatures （DBT）. The objective was to evaluate the spatial distnbution of temperatures in buildings according to spatial and temporal Dynamic CUmato[ogy approaches. An experimental, typical day for heat conditions was determined. The data of the main climatic vari- ables provided by an automatic weather station and temperatures inside the test cells were collected using thermocouples installed such that the entire space is included. The results led to the conclusion that the LGR has a balanced IST and DBT spatial distribution compared with ceramic roofs. Nevertheless, the analysis of the thermal performance is only one of the variables that must be considered when developing a construction proposal that is adapted to the context. The manner in which the thermocouples were placecl inside the test cells also showed the importance of specifying the location of the sensors in experimental studies on the behavior and thermal performance of buildings.