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In this note, the effects of heating and cooling rate on the transformation characteristics in TiNiCu shape memory alloy were investigated by differential scanning calorimetry (DSC). The results showed that the martensitic end transformation temperature (Mf) and reverse end transformation temperature (Af) depend strongly on the scanning rate of the heating–cooling process, Mf decreased and Af increased with increasing cooling/heating rate. However, the martensitic start transformation temperature (Ms) and reverse start transformation temperature (As) are not so sensitive to the scanning rate. The results are in good agreement with simulation results of our previous published model of martensitic transformation [Y. Huo, X.T. Zu, A. Li, Z.G. Wang, L.M. Wang, Acta Mater. 52 (2004) 2683].

The aim of this innovative educational project is to encourage students’ interest in one of the most underrated fields of architecture: building services. With this material students interact with real elements and thereby understand the relationship between facilities and the building. A set of three small technical cabinets is planned. They allow for comfortable use and movement inside the building, need minimum maintenance and are easily stored. The result is an alternative concept of a mobile laboratory called a ‘technical cabinet’, made up of three mobile units for fire safety, electricity and the heating/cooling system. The design, content and learning systems of the cabinets confirmed the validity of the initial concept during the first year of use. A protocol has also been developed for each of the technical cabinets so that the teaching experience may be of use in other Schools of Architecture.

The LT Method is an energy-design tool which responds to parameters available early in the design development. It provides an output of annual primary energy for lighting, heating cooling and ventilation. This paper introduces LT 3.01, a version for Southern Europe which includes a procedure to evaluate the affect of shading devices on cooling loads and on lighting.

Metallic samples subjected to heating-cooling cycles undergo a permanent change in their length. The difference between the initial length and the length at the end of the cycle (residual strain) depends on the maximum temperature attained during the cycle. This dependence of residual strain on the maximum temperature of the cycle is similar for all of the examined metals (polycrystalline copper, aluminium, iron, gold, lead and single-crystal copper). Upon further increasing this temperature, the metal residual strain changes from positive to negative values. The temperature at which the maximum positive residual strain occurs is characteristic for each metal. The value of the residual strain and the temperature at which it changes its sign depend on the previous thermal history of the metal.

A sample mount which can be moved throughout an ultra‐high‐vacuum environment and through a load‐lock to atmosphere is described. A sample mount holder station is also shown whereby the sample temperature can be monitored and controlled from 80 K to the sample melting point. A unique feature is that the temperature is measured with a thermocouple cemented to the sample, but the sample remains transportable. Contacts to electrically isolated side arms on the sample mount provide the correct electrical connections.

This study aims to present the mechanical behavior of carbon fiber reinforced polymers (CFRP) reinforced low strength cylindrical and prism concrete specimens under both heating-cooling cycles and sustained loading. Heating-cooling cycles range from -10 to 50A degrees C and the applied sustained load level is 40% of the ultimate strength of concrete. After 200 heating-cooling cycles and/or sustained load testing, specimens were tested to determine the mechanical behavior under uniaxial compression. The experimental test results show that heating-cooling cycles alone have insignificant effect on the mechanical properties of CFRP-wrapped specimens. However, as for simultaneous exposure of sustained loading and heating-cooling cycles the main difference is on the shape of the stress-strain diagram, in which the bilinear response becomes clear. The other difference is on the ultimate strain, which decreases up to 29 and 15% for cylindrical and prismatic specimens, respectively.

This paper analyzes the coefficient of performance separately for the heat pump and separately for the heating system-cooling heat pump. Stationary mathematical model with concentrated state parameters has been created. The analysis was done with the mathematical models of coefficient of performance for heat pumps and separately for the heating-cooling system with heat pump. For the analysis, graph-analytical method optimization was applied. The numerical results are presented in graphics.

Experiments with heating and cooling cycles in undrained constant total stress conditions in triaxial apparatus are presented. Heating induces a large pore-water pressure increase, which eventually leads to a large irreversible strain and possible mechanical failure. Subsequent cooling produces a drop in water pressure. In one test the drop during cooling was more than two times higher than the previous increase during heating, reaching values of up to 2.30 MPa. An analysis of these findings in terms of a thermoplastic model is presented. The interpretation of these tests relies heavily on the kind of stress-partitioning hypothesis that is used. It was found that the described phenomena can be quantitatively dealt with using the classical effective stress principle, if the shear strength and consolidation are described in terms of temperature-dependent plastic yield limit. Key words : temperature, plastic strains, effective stress, pore pressure.

The effects of heating/cooling cycles on the structure and catalytic properties of CUCl2KCl catalysts supported on Al2O3 and SiO2 have been studied. It is demonstrated that after the catalysts are heated to 673 K and cooled to room temperature, an irreversible segregation of K and Cu occurs. X-ray diffraction (XRD), differential thermal analysis (DTA), electron paramagnetic resonance (EPR), and scanning electron microscopy (SEM) analysis have experimentally confirmed the proposed segregation. This segregation process appears to be the main cause of the deactivation observed on SiO2-supported CUCl2KCl catalysts for the CH4 oxychlorination reaction after a heating/cooling cycle. On γ-Al2O3 the situation is somewhat different. Due to the strong affinity of Cu for the Al2O3 support a surface Cu oxychloride species is stabilized and the segregation process is consequently enhanced. However, the deactivation is not evident on this catalyst because the stabilized surface Cu oxychloride species has its own catalytic activity. On the other hand, when La is added to the CUCl2KCl catalysts a significant improvement in activity, which is maintained over a heating/cooling cycle, is observed. This promoter effect may be ascribed to the action of La as an inhibitor of KCu segregation.

ABE-381, a 7-page illustrated fact sheet by Clyde W. Fraisse, John Bellow, and Charles Brown, discusses how growers can use the AgClimate Web site to find out how to predict Growing Degree Day accumulation for the current season, and to review GDD for past seasons. Includes references. Published by the UF Department of Agricultural and Biological Engineering, October 2007. ABE381/AE428: Degree-Days: Growing, Heating, and Cooling (ufl.edu)

The active heating/cooling requirements to thermally sustain a human subject submerged in 10, 20, 30 and 40 °C water was measured using a system that circulated water through a zoned tubesuit garment. Water at 30 °C was circulated through the garment at a flow rate of about 0.5 L/min to each of six body regions and the outlet temperatures were measured. In addition, skin and core temperature, heat flux, and oxygen consumption was measured. The subject wore either a 6.5 mm or a 3 mm foam neoprene wetsuit. Body temperatures and heat fluxes reached steady state after 30–90 minutes and the immersions lasted 2–4 hours and core and skin temperatures remained within set thermal limits. In both wetsuits there was a linear correlation between the thermal exchange of the tubesuit and water temperature. While in the 6.5 mm wetsuit −214 to 242 W of heating (−) or cooling (+) was necessary in 10 to 40 °C water, respectively. While wearing the 3 mm wetsuit −462 to 342 W was necessary in 10 to 40 °C water, respectively. It was therefore concluded that a subject can be kept in thermal balance and comfort in 10–40 °C water with active heating/cooling.Copyright © 2007 by ASME

International audience; Designed for the simulation of transformation induced plasticity in steels occurring on cooling, the model first proposed by Leblond in the middle of 80's works well for constant uni-axial stress test. But further experimental investigation have shown that for non-proportional multi-axial test, the quality of the model is worse. The purpose of this paper is to improve this model through the removal of the hypothesis that plastic flow for the Greenwood–Johnson mechanism occurs only in the ‘weaker’ phase. The improvement, leading to better agreement, enables to use the model on cooling, and shows that for TRIP plastic flowing in harder phase is almost important, even if it is lower than in the ‘weak’ phase.

Under a scientific and technical cooperation between CRF and Politecnico di Milano, the hybrid photovoltaic-thermal (PVT) facade of the FIAT Research Center (CRF) was realized near Turin in Italy. In the present work, a detailed analysis of monitored data on the thermal and electrical performances of hybrid solar facade is presented. Using the simulation model, an estimated data for annual energy (thermal and electrical) production from the solar facade is also shown. The validation of simulation model with the experimental data is also carried out.

The discovery of extended, approximately spherical weak shock waves in the hot intercluster gas in Perseus and Virgo has precipitated the notion that these waves may be the primary heating process that explains why so little gas cools to low temperatures. This type of heating has received additional support from recent gasdynamical models. We show here that outward propagating, dissipating waves deposit most of their energy near the center of the cluster atmosphere. Consequently, if the gas is heated by (intermittent) weak shocks for several Gyrs, the gas within 30-50 kpc is heated to temperatures that far exceed observed values. This heating can be avoided if dissipating shocks are sufficiently infrequent or weak so as not to be the primary source of global heating. Local PV and viscous heating associated with newly formed X-ray cavities are likely to be small, which is consistent with the low gas temperatures generally observed near the centers of groups and clusters where the cavities are located., 14 pages; Accepted by ApJ

Publisher Summary The effective use of energy in a chemical plant results from employing the combination of processes that consumes the least amount of exergy as a whole in manufacturing the products. To examine the flow of exergy, the diagram that visualizes the exergy balance in manufacturing processes has practically been used for the purpose of improving the exergy efficiency in the plants. Furthermore, a novel concept of exergy vectors has been brought forth to evaluate the exergy efficiency of various processes on an enthalpy–exergy diagram. By means of exergy vectors, the minimum exergy thermodynamically required for a manufacturing process may be estimated in the diagram. This chapter describes the principle of exergy vector diagrams and their application to basic processes such as heating cooling, compression–expansion, separation mixing, and chemical reactions.

In order to make the electronic transport mechanism in organic substances clear in detail, the thermally stimulated current (TSC) method is very effective. From the TSC method, three parameters such as an energy depth E/sub t/ [eV] of the carrier trap site, a preexponential parameter (or an escape frequency factor) /spl nu/ [s/sup -1/] and a charge carrier density n/sub t/ [m/sup -3/] relating to the phenomena, can be estimated. We have completed some theories that enable us to analyze in detail TSC data obtained experimentally. One of them, the asymptotic estimation method (AEM) originally proposed by us, enables us to evaluate these three parameters accurately. And this has been expanded extensively to estimate 3N parameters, through an exact auto-separation (AS) method of various composite TSC curves and through the reconstruction (RC) method of TSC curves with no peak obtained by partially repeated heating cooling procedures. Where N is the number of the single TSC curve of the first-order included in the objects. The fine advantages are that these expanded theories have higher accuracy than 4 significant figures. Then, detail analyses of discrete states became possible by using both methods.

International audience; Well known in the North of Europe, the water ceiling panel systems are mainly used to provide cooling. However, as well as for a radiant floor, this system can be used for heating in winter and cooling in summer. In order to get a better knowledge of the energy performances of such devices, the Gaz de France Research Centre funded a test campaign during two winters and one summer. This experimental study was carried out in our laboratory, located in Rennes, in western France. A water ceiling panel system and a monitory data acquisition system were installed in a test room. The studied ceiling panel system was made of copper pipes with rigid aluminium diffusion fins. The used materials presented a good heating conductivity and the ceiling radiant panel was fast-acting. Simulation models were developed with the simulation program TRNSYS, using the experimental study results for the code verification.

The heating/cooling potential of a typical sunspace has been investigated in the present study as a function of different climatic conditions in several locations throughout Europe. Passive solar design is mainly concentrated on providing space heating during winter as well as on avoiding overheating during the summer period. In the present paper the feasibility of a sunspace as a heating system was studied taking into account the climatic conditions. Simultaneously, various passive cooling techniques are proposed and examined in order to avoid overheating during summer. For this reason, a representative case study is presented and simulated for several climatic conditions. The simulated results showed that sunspaces can be an appropriate and effective system all over Europe during the cold period of the year. Thermal mass within buildings, shading devices, buried pipes and night ventilation techniques can be essential and effective methods to control overheating during summer. © 2002 Elsevier Science Ltd. All rights reserved.

The technique consisting in using a Peltier cell in contact with the material and producing successively heating and cooling conditions is presented for the measurement of diffusivity. Results on thermally thin materials with well known characteristics like stainless steel AISI 304 gives measurement values with precision around 10%. Analyzing the situation of a thermally thick marble sample, the in-depth propagation affects also the lateral ones. This is of general interest for a future use of this technique in the field where the thickness of the material may be important.

In his paper, Banks (2011) discusses the possibility of deriving an exact analytical solution to the hydraulic travel time along a flow line of his well-doublet scenario. The solution is given as follows, providing a general solution for the (hydraulic) travel time, t t, along the x -axis from any point to an abstraction well (or from the injection well to any point on the x -axis). The third solution (β > 1, α = −1) already appears in Banks’s paper as equation (5). The …

Active solar energy systems may be employed in residential and commercial/industrial buildings for the provision of space conditioning (heating and/or cooling) and/or hot water. Another common application is the heating of swimming pool water.

This manual specifies a method for calculating the overall thermal transmittance (also referred to as the overall U-value or U{sub o}), heating load, and cooling load of a manufactured (mobile) home. Rules, examples, and data required by the method are also presented. Compliance with the Department of Housing and Urban Development's (HUD) U{sub o} and load calculation regulations contained in Sections 3280.506, 3280.510 and 3280.511 of the Manufactured Home Construction and Safety Standards must be demonstrated through the application of the method provided herein.

The study of the intercalation of organic compounds into clays, as in the preparation of pillared clays, is of great importance both from the theoretical point of view and for its applications in pharmacy, agriculture, clay characterization, catalysis, etc. (MacEwan and Wilson, 1980; Theng, 1974; Pinnavaia, 1983). At dif- ferent temperatures, intercalated organic molecules, es- pecially long-chain molecules, can undergo reversible phase transitions, and hydratable cations can hydrate to different degrees. These phenomena can be followed by studying the variation in X-ray powder diffraction (XRD) basal spacing with temperature (Brindley and Ray, 1964; Lagaly and Weiss, 1971; Pfirrmann et al.,1973). Although various temperature-control stages for powder X-ray diffractometers have been described in the literature (Brown et aL, 1972; Lagaly et aL, 1975; Morandi et al., 1976-1977), the advantage of the sys- tem described here is that XRD patterns can be ob- tained more simply and quickly for temperature ranges both below and above ambient room temperature and with greater temperature stability, due to the simul- taneous use of cold and heat sources.

The effects of heating/cooling cycles on the structure and catalytic properties of CUCl2KCl catalysts supported on Al2O3 and SiO2 have been studied. It is demonstrated that after the catalysts are heated to 673 K and cooled to room temperature, an irreversible segregation of K and Cu occurs. X-ray diffraction (XRD), differential thermal analysis (DTA), electron paramagnetic resonance (EPR), and scanning electron microscopy (SEM) analysis have experimentally confirmed the proposed segregation. This segregation process appears to be the main cause of the deactivation observed on SiO2-supported CUCl2KCl catalysts for the CH4 oxychlorination reaction after a heating/cooling cycle. On γ-Al2O3 the situation is somewhat different. Due to the strong affinity of Cu for the Al2O3 support a surface Cu oxychloride species is stabilized and the segregation process is consequently enhanced. However, the deactivation is not evident on this catalyst because the stabilized surface Cu oxychloride species has its own catalytic activity. On the other hand, when La is added to the CUCl2KCl catalysts a significant improvement in activity, which is maintained over a heating/cooling cycle, is observed. This promoter effect may be ascribed to the action of La as an inhibitor of KCu segregation.

A heating-cooling stage with detachable thermocouple contacts and an electron beam heater has been designed and tested for use in temperature programmed desorption and scanning tunneling microscopy (STM) experiments. This sample stage is compatible with the Omicron variable temperature STM, and the thermocouple contacts can be used with both the standard Ta plates and the variable temperature sample holder. The stage can also be retrofitted to the standard Omicron manipulation stage without requiring any additional electrical connections.

The shrinkage characteristics of PVC pipe during heating-cooling cycles are discussed. It is found that very high shrinkage can be observed after heating-cooling cycles and the shrinkage approaches a limit after a number of cycles. The density of the material is found not to change after shrinkage.

1. 1. Heating and cooling rates, and standard metabolic rates of Varanus bengalensis were measured. 2. 2. The cooling to heating ratio was 0.63. 3. 3. The mean oxygen consumption at 30°C (0.051 ml O 2 /g-hr) was higher than expected compared to a lizard of comparable weight. 4. 4. The Q 10 values (standard oxygen consumption) of 6.26 at 10–20°C decreasing to 1.82 at 20–40°C correlate with previously determined values for varanids. 5. 5. This suggests that varanids have the capability of extended activity ranges.

This paper discusses the problems of modeling, simulation, and control of an oil heater. The decoupling control system is designed with the help of simulation and is evaluated using the inverse Nyquist array method. Much emphasis is placed on digital and analog computer simulation. The decoupling control system has been implemented with a single-board microcomputer and has worked well for over a year.