Theoretical Investigation On The Barocaloric And Magnetocaloric Properties In The Gd5 Si2 Ge2 Compound

817 words - 4 pages

Figure 1 shows the temperature dependence of magnetization in Gd5Si2Ge2 compound at and at atmospheric pressure. Open symbols are the experimental data and the solid symbols represent the theoretical curve. The circles are for sample heating and triangles are for sample cooling. The value of saturation magnetization at 8 K in the theoretical curve was normalized with the experimental data. The values of and were adjusted according to the critical temperatures from the M vs. T curves (Fig. 1) at atmospheric pressure for sample heating and cooling (table 1). It is worth noticing that fixes the Curie temperature and is responsible for the existence of first order magnetic phase transition and fixes the thermal hysteresis of about 5 K.
Table 1 shows the values of our model parameters adjusted to fit the experimental data for the pressures 1.5, 2.0 and 2.9 kbar. Values of model parameters used in the theoretical curves adjusted at zero magnetic field.
Figure 2 shows the isothermal entropy changes heating the sample (a), (b) and (c) and (the figure 3 cooling the sample (a), (b) and (c)). The solid curves are due to the variations from atmospheric pressure (P^at) to applied pressure, P=1.5 kbar (fig.2a and fig.3a), P=2.0 kbar (fig.2b and fig.3b), P=2.9 kbar (fig.2c and fig.3c) without applied magnetic field (µ_0 h_0=0 T) for sample heating and cooling, as indicated by the arrows. The open circles and open squares represent 〖ΔS〗_T vs. T experimental data for Gd5Si2Ge2 which are in good agreement with our theoretical curves for sample heating and cooling, respectively [19]. The value was used for this compound in our theoretical curves [28], value that we kept in our model in all theoretical curves. For all pressure changes, the Grüneisen parameters at atmospheric and applied pressures (Γ^at=0.13 and Γ^app) were adjusted (see table 1) leading to the calculated curves shown in the fig.1 and fig.2 for P=1.5,2.0 and 2.9 kbar. The dotted curves are due to the variation of pressure (from atmospheric to P = 1.5, 2.5 and 2.9 kbar), simultaneously under the intensity of the applied magnetic field change from zero to 5 T.
Figure 4 shows the thermal hysteresis for...

Find Another Essay On Theoretical investigation on the barocaloric and magnetocaloric properties in the Gd5Si2Ge2 compound

Benzene: The Physical Properties and Chemical Properties

977 words - 4 pages Benzene from an oily film that deposited from the gas used for lighting. Benzene has a great effect on the environment and health though exposure and effects may vary depending on the life style of a person. The physical properties and chemical properties are essential to a chemical compound, these properties help identify the substance. Some of Benzene’s physical properties include viscosity and the physical state of the substance. Benzene is

Comparing And Contrasting Two Theoretical Views On Arousal/Performance Relationship In The Sports Context

810 words - 4 pages The two theoretical views on the relationship between arousal and performance in the sports context are the Drive theory and the Inverted-U theory but first, we define arousal and performance in sports context.The relationship between physiological arousal and motor performance has been of interest to psychologist since the early 1900's. Research led to the development of the two theories stated above. Arousal is a requisite for optimal sport

Investigating the Compound Microscope

1735 words - 7 pages done quickly and also was able to be done carefully.As it can be seen on the first 3 graphs, the theoretical magnification and the actual magnification differs so much compared to the other 6. Although the graphs from graph 3 – 9 might have small differences between the actual and the theoretical magnification, they only differ by +/- 2. Through out the experiment, the group re-did every single experiment again and again till the difference

CFUs/mL; Organoleptic Properties; and the effects of temperature, acid and enzymes on proteins in Selected Milks

2818 words - 11 pages CFUs/mL; Organoleptic Properties; and the effects of temperature, acid and enzymes on proteins in Selected MilksAbstract: This experiment examined the organoleptic properties, coagulation of proteins and microbial contamination of cow's milk. Various samples of milk were tasted for their sweetness, mouth-feel, cooked taste and creaminess, colour was also noted. Low fat milks were less creamy and less viscous than those with full milk fat

Discovery of the Compound Buckminsterfullerene

1256 words - 5 pages hollow ball. A molecule with a shape like this is sure to have interesting properties, and it does indeed. Strength, stability, superconductivity, and biological harmlessness are some of the favorites. Buckminsterfullerene first gave scientists a hint of its presence in the early 1980's when tests on carbon soot from space showed inexplicable bumps on otherwise smooth graphs. Further tests involved a machine designed to produce clusters of

Theoretical Perspectives in Sociology. Explain what theoretical perspectives are. Name and explain the three major sociological theoretical perspectives and give examples

1312 words - 5 pages external factors influencing them, should be observed. There are several theoretical perspectives in sociology that are used to understand social relationships and behaviors. The three theoretical perspectives discussed here are symbolic interactionism, functional analysis, and conflict theory.Symbolic interactionism is a microsociological theoretical approach that examines small-scale patterns of social interaction. Interactionists focus on how

Investigation on the Enzyme Trypsin

3834 words - 15 pages Investigation on the Enzyme Trypsin An Investigation determining a factor affecting the rate of digestion of gelatin by the protease trypsin. Introduction An enzyme is a biological catalyst, which speeds up reactions. An example of this in the human body is trypsin (a protease produced in the pancreas and used in the stomach), which catalyses the digestion of gelatine, a protein. For this investigation, a

Phase transition and electrical properties of Barium-modified SrBi4Ti4O15 Bi- layered compound

610 words - 3 pages that the properties of the SBT compound strongly dependent on the chemical elements at the A or B site and can be tailored by doping with a suitable dopant at either of these sites[14,15]. But, the effect of A-site substitution is more obvious than that of B-site substitution, as the cation in the B-site are similar in size and do not play a major role in structurl distortion[16]. It is also not possible to substitute other cation into the

The Materials, Properties, and Theory of Superconductivity

1505 words - 6 pages The purpose of this paper is to examine the materials, properties, and theory of superconductivity, a quantum phenomenon that occurs when a material is brought below a critical temperature and will conduct electricity without any resistance, the nearest model in nature to perpetual motion. According to Ecks (1990), Once current is applied to a superconducting material the current will continue in a closed lope without ever losing intensity

Investigation on the Effects of 5’- and 3’-Untranslated Regions on Recombinant Hydrogenase Activity in the Chlamydomonas Reinhardtii Chloroplast

1796 words - 7 pages Abstract The availability of a Chlamydomonas Reinhardtii strain without a nuclear hydrogenase gene has opened the door for exploration of the Hyd gene in the chloroplast. Biolistics and homologous recombination provide a well understood tool for integrating recombinant genetic material into the C. Reinhardtii chloroplast. The effects of different 5’- and 3’-untranslated regions on hydrogen production catalyzed by a eukaryotic hydrogenase will

Modelling the influence of two-phase fault rock properties on CO2 storage in faulted saline aquifers

1167 words - 5 pages trigger hydraulic fracturing of the caprock and/or reactivation of existing faults. As a result, either lower injection rates or more injection rates than would be considered necessary on the basis of accounting only for single phase properties, may be required to accommodate the two-phase fault-rock effects. In this study we have used idealized 2D flow simulation models to investigate the relationship between pressure compartmentalization, two

Similar Essays

Theoretical Investigation On The Barocaloric And Magnetocaloric Properties In The Gd5 Si2 Ge2 Compound

756 words - 4 pages Recently Yuce and coworkers reported high barocaloric effect in the well know giant magnetocaloric material Gd5Si2Ge2 around the first order magnetic phase transition. In this paper, we propose a theoretical microscopic model to discuss the barocaloric and magnetocaloric effects in the Gd5Si2Ge2 compound. For this purpose, our model Hamiltonian contains three interactions: Zeeman, magnetoelastic and exchange interactions. Also, magnetic field

An Investigation Into The Identification, Properties, And Synthesis Of An Unknown Ionic Compound

1186 words - 5 pages Abstract This paper describes the methods used in the identification, investigation of properties, and synthesis of an unknown compound. The compound was identified as calcium nitrate by a variety of tests. When the compound was received, it was already known to be one of twelve possible ionic compounds. The flame test identified the presence of the calcium anion in the compound. The compound tested positive for the nitrate cation using the

Chronic Sorrow In The Field Of Nursing: A Theoretical Investigation

1474 words - 6 pages tension (Teel, 1991, p. 1312). These symptoms can also present with chronic sorrow, but in the case of grief, are generally resolved within 4 to 6 weeks (Teel, 1991). Chronic sorrow lasts significantly longer than grief and is distinguished by the presence of “a pervasive psychic pain” that is often brought on when the ongoing loss is made salient, particularly when the ill person remains in a person’s physical environment and serves as a reminder of

Investigation The Effect Of Paper Properties On Color Reproduction Of Digital Printing

976 words - 4 pages C451, the Konica Minolta bizhub C451 has larger gamut volume although Konica Minolta bizhub C450 has larger color gamut in blue and magenta area. Figure 2 show printers produce relatively different color gamut shape. As mentioned before comparing the results in terms of gamut volume show, Konica Minolta CF3102 printer has larger gamut volume for the selected paper A. Therefore this printer chooses for investigation the effect of paper