Physical chemistry is an unexpected shock to many university students. From the semi-
empirical approaches of the school laboratory, first year undergraduates suddenly find
themselves propelled into an unexpected quagmire of definitions and equations. Worse
still, although the applicability of the subject is sometimes obvious, studying the behavior
of a particle in an infinitely deep well can seem nothing short of farcical on first
The closed engine test cell system makes a suitable case for students to study an example of the flow of heat and change in entropy. In almost all engine test cells the vast majority of the energy comes into the system as highly concentrated ‘chemical energy’ entering the cell via the smallest penetration in the cell wall, the fuel line. It leaves the cell as lower grade heat energy via the largest penetrations: the ventilation duct, engine exhaust pipe and the cooling water pipes.
This book is based on a course that I have been teaching for the past several years to
first year graduate students in the biological sciences at Duke University. These stu-
dents have not studied physical chemistry as undergraduates and typically have not
had more than a year of calculus. Many faculty believe that an understanding of the
principles of physical chemistry is important for all students in the biological sciences,
and this course ...
The relationship between macroeconomic variables and stock market returns
is, by now, well-documented in the literature. However, a void in the literature
relates to examining the cointegration between macroeconomic variables and
stock market’s sector indices rather than the composite index. Thus in this
paper we examine the long-term equilibrium relationships between selected
macroeconomic variables and the Singapore stock market index (STI), as well
as with various Singapore Exchange Sector indices—the ﬁnance index, the
property index, and the hotel index.
This paper studies the impact of written language variations and the way it affects the capitalization task over time. A discriminative approach, based on maximum entropy models, is proposed to perform capitalization, taking the language changes into consideration. The proposed method makes it possible to use large corpora for training. The evaluation is performed over newspaper corpora using different testing periods. The achieved results reveal a strong relation between the capitalization performance and the elapsed time between the training and testing data periods. ...
Among spinel ferrites, Cd and Zn ferrites are always normal ferrites with Cd and Zn ions locating only in tetrahedral sites. This study presents effect of Zn on the magnetic and magnetocaloric properties of the mixed spinel ferrites Ni1-xZnxFe2O4 (x = 0.60, 0.65, 0.70, 0.75). The presence of Zn affects lattice parameters, saturation magnetization Ms, Curie temperature, Tc, and magnetic entropy change ∆Sm. At highest Zn content, Tc reduces to the temperature lower than room temperature and magnetic structure of spins in the octahedral sublattice should be strongly canted. ...
Chapter 7 (part 1) - Entropy: A measure of disorder. The objectives of Chapter 7 are to: Apply the second law of thermodynamics to processes; define a new property called entropy to quantify the second-law effects; establish the increase of entropy principle; Calculate the entropy changes that take place during processes for pure substances, incompressible substances, and ideal gases.
Fe73.5Si13.5B9Nb3Au1 ribbons have been prepared by rapid cooling on a single copper wheel with different speeds of wheel of 10, 20, 30, and 40 m/s. The as-spun samples are amorphous. Upon annealing, the nanocrystalline phases are formed. Increasing the cooling rate leads to thinner ribbons, higher crystallization activation energy and crystallization volume fraction of the α-Fe(Si) phase, slightly increasing Curie temperature and soft magnetic properties of annealed ribbons. The large magnetic entropy change is observed for sample with v = 30 m/s.
Study of the effect of Nd substitution for La on magnetocaloric effect (MCE) of polycrystalline perovskites (La1-xNdx)0.7Sr0.3MnO3 (x = 0.0, 0.2 , 0.4, 0.6, 0.8, 1.0 ) is presented. Large MCE is observed in all samples. The presence of Nd affects to both maximum magnetic entropy change, |∆Sm|max, and Curie temperature, TC. |∆Sm|max slightly reduces with low content and increases with high content of Nd and gets maximum value of 4.83 J/kg.K for x = 0.8. TC of the samples determined from the
The kinetics of the reversible thermal unfolding, irreversible
thermal unfolding, and reductive unfolding processes of
bovine pancreatic ribonuclease A (RNase A) were investi-gated in NaCl/Pi solutions. Image parameters including
Shannon entropy, Hamming distance, mutual information
and correlation coefficient were used in the analysis of the
CD and 1D NMR spectra. The irreversible thermal
unfolding transition of RNase A was not a cooperative
process, pretransitional structure changes occur before the
main thermal denaturation....