Transient state work fluctuation theorem for a classical harmonic oscillator linearly coupled to a harmonic bath

Based on a Hamiltonian description we present a rigorous derivation of the transient state work fluctuation theorem and the Jarzynski equality for a classical harmonic oscillator linearly coupled to a harmonic heat bath, which is dragged by an external agent. Coupling with the bath makes the dynamics dissipative. Since we do not assume anything about the spectral nature of the harmonic bath the derivation is not restricted only to the Ohmic bath, rather it is more general, for a non-Ohmic bath. We also derive expressions of the average work done and the variance of the work done in terms of the two-time correlation function of the fluctuations of the position of the harmonic oscillator. In the case of an Ohmic bath, we use these relations to evaluate the average work done and the variance of the work done analytically and verify the transient state work fluctuation theorem quantitatively. Actually these relations have far-reaching consequences. They can be used to numerically evaluate the average work done and the variance of the work done in the case of a non-Ohmic bath when analytical evaluation is not possible.

Structure of the noncubic phase in the ferroelectric state of Pr-substituted SrTiO3

Sr1−xPrxTiO3 has recently been shown to exhibit ferroelectricity at room temperature. In this paper powder x-ray and neutron-diffraction patterns of this system at room temperature have been analyzed to show that the system exhibits cubic (Pm-3m) structure for x<=0.05 and tetragonal (I4/mcm) for x>0.05. The redundancy of the noncentrosymmetric structural model (I4cm) in the ferroelectric state suggests the absence of long-range ordered ferroelectric domains and supports the relaxor ferroelectric model for this system.

Nanopatterning by solid-state dewetting on reconstructed ceramic surfaces

We demonstrate ordered array formation of Au nanoparticles by controlled solid-state dewetting of a metal film on stepped alumina substrates. In situ transmission electron microscopy studies reveal that the dewetting process starts with nucleation of ordered dry regions on the substrate. The chemical potential difference between concave and convex surface regions induces anisotropic metal diffusion leading to the formation of nanowires in the valleys. The nanowires fragment due to Rayleigh instability forming arrays of metal nanoparticles on the substrate. The length scale of reconstruction relative to the starting film thickness is an important parameter in controlling the spatial order of the nanoparticles.

Cloning Of Rice Dna And Identification Of Transfer-Rna Gene Clones

THE rapid development of recombinant DNA technology has brought forth a revolution in biology'>", it aids us to have a closer look at the 'way genes are organized, eS11 ecially in the complex eucaryotic genornes'<", Although many animal and yeast genes have been studied in detail using recombinant DNA technology, plant genes have seldom been targets for such studie., Germination is an ideal process to study gene expression .because it effects a . shift in the metabolic status of seeds from a state of 'dormancy to an active one. AJ;l understanding of gene organization and regulation darin.g germination can be accomplblted by molecular cloning of DNA from seeds lik.e rice. To study the status of histone, rRNA tRNA and other genes in the rice genome, a general method was developed to clone eucarvotic DNA in a' plasmid vector pBR 322. This essentially ~ involves the following steps. The rice embryo and plasmid pBR 322 DNAs were cut witll restriction endonuclease Bam Hi to generate stick.Y ends, The plasmid DNA was puosphatased, the DNA~ ware a~·tnealed and joined 'by T4 phage DNA ligase. The recombinant DNA molecules thus produced were transjerred into E. coli and colonies containing them Were selected by their sensitivity to tetracycline and resistance to ampicillin, Two clones were identified . 2S haVing tRNA genes by hybridization of the DNA in the clones \vitl1 32P-la.belled rice tRNAs.

Reversible photodimerization of phenylbutadienes in the solid state

Based on x-ray crystallographic studies, it is shown that crystal chemical factors govern the reversible photodimerization of phenylbutadienes in the solid state.

Effect of pregnant mare serum gonadotropin on the induction and degradation of FSH and LH receptors in the granulosa cell of the immature rat

The relative induction of FSH and LH receptors in the granulosa cells of immature rat ovary by pregnant mare serum gonadotropin (PMSG) has been studied. A single injection of PMSG (15 IU) brought about a 3- and 12-fold increase in FSH and LH receptor concentration,respectively, in the granulosa cells. Maximal concentration was reached by 72 h but the receptor levels showed a sharp decline during the next 24–48 h. The kinetic properties of the newly formed FSH receptors were indistinguishable from the pre-existing ones. The induced FSH receptors were functional as demonstrated by an increase in the in vitro responsiveness of the cells to exogenous FSH in terms of progesterone production. Treatment of immature rats with cyanoketone, an inhibitor of Δ5,3β-hydroxysteroid dehydrogenase, prior to PMSG injection effectively reduced the PMSG-stimulated increase in the serum estradiol, uterine weight and LH receptors but had no effect on the FSH receptor induction. The ability of PMSG to induce gonadotropin receptors can be arrested at any given time by injecting its antibody, thereby suggesting a continuous need for the hormonal inducer. Estrogen in the absence of the primary inducer was unable to maintain the induced LH and FSH receptor concentration. Inhibition of prostaglandin synthesis using indomethacin also had no effect on either the induction or degradation of gonadotropin receptors. Administration of PMSG antiserum, 48 h after PMSG injection, brought about a rapid decline in the induced receptors over the next 24 h, with a rate constant and \iota 1/2 of 0.078 h−1 and 8.9 h for FSH receptors and 0.086 h−1 and 8.0 h for the LH receptors, respectively.

Optically active gossypol as a circular dichroism probe of interactions with serum albumins

The (+)-enantiomer of the polyphenolic binaphthyl gossypol, has been shown to be a useful CD probe of interactions with human and bovine serum albumin. (+)-Gossypol binds to albumin with same affinity as recemic (±)-gossypol, as shown by fluorescence quenching, and also displaces bilirubin from its albumin binding site. The CD characteristics of bound gossypol are different in the case of the two proteins.

Solid-state Thermal Polymerization of Sodium Acrylate

Initiation and propagation processes in thermally initiated solid-state polymerization of sodiumvacrylate have been studied. The kinetics of initiation, followed with the electron spin resonancev technique, leads to an activation energy E of 28.8 kcal/mol, which is attributed to the formation of dimeric radicals. The activation energy of 16 f 1 kcaVmol obtained for the solid-state polymerization of sodium acrylate by chemical analysis and differential scanning calorimetry has been attributed to the propagation process.

Calorimetric, infrared and ESR studies of the plastically crystalline state of organic compounds

Enthalpy changes of the crystal-plastic and plastic-liquid transitions are related to the temperature range of stability of the plastic phase. Thermodynamics of the plastic state of binary mixtures have been examined. Infrared correlation times, τc, and activation energies have been measured for a few molecules in the plastic state. Molecular tumbling times, τt, have also been measured employing ESR spectra of a spin-probe. Plots of log τc(τt) 1/T are continuous through the plastic-liquid transition. Activation energies for molecular motion seem to vary in the same direction as the ΔH of the plastic-crystal transition. Infrared correlation times of solute molecules in binary solutions in the plastic and the liquid states show interesting variations with solute concentration.

Characterization of alinite cements through X-ray diffraction and mas 29Si NMR studies

Alinite cements have been synthesized using mining and steel plant wastes and pulverized fuel ash (fly ash) as raw materials and a clinkering temperature of 1150°C. The cements possess hydration characteristics comparable to those of portland cements. X-ray diffraction studies on these samples confirm the presence of alinite as the predominant phase. MAS 29Si NMR spectra have been used to distinguish alinite and alite cements. While both show resonances characteristic of Q° type silicate species, the portland cements exhibit three distinct peaks corresponding to three inequivalent SiO4 units present, while alinite shows a single sharp peak corresponding to the unique Si position.

A DLTS technique for surface state capture cross-section measurement of MOS diodes

A modified DLTS technique is proposed for the direct measurement of capture cross-section of MOS surface states. The nature of temperature and energy dependence σn is inferred from data analysis. Temperature dependence of σn is shown to be consistent with the observed DLTS line shapes.

Effect of inter-edge Coulomb interactions on transport through a point contact in nu=5/2 quantum Hall state

We study transport across a point contact separating two line junctions in a nu = 5/2 quantum Hall system. We analyze the effect of inter-edge Coulomb interactions between the chiral bosonic edge modes of the half-filled Landau level (assuming a Pfaffian wave function for the half-filled state) and of the two fully filled Landau levels. In the presence of inter-edge Coulomb interactions between all the six edges participating in the line junction, we show that the stable fixed point corresponds to a point contact that is neither fully opaque nor fully transparent. Remarkably, this fixed point represents a situation where the half-filled level is fully transmitting, while the two filled levels are completely backscattered; hence the fixed point Hall conductance is given by G(H) = 1/2e(2)/h. We predict the non-universal temperature power laws by which the system approaches the stable fixed point from the two unstable fixed points corresponding to the fully connected case (G(H) = 5/2e(2)/h) and the fully disconnected case (G(H) = 0).

A DC-link Capacitor Voltage Balancing with CMV Elimination using only the Switching State Redundancies for a Reduced Switch Count Multi-Level Inverter fed IM Drive

Common mode voltage (CMV) variations in PWM inverter-fed drives generate unwanted shaft and bearing current resulting in early motor failure. Multilevel inverters reduce this problem to some extent, with higher number of levels. But the complexity of the power circuit increases with an increase in the number of inverter voltage levels. In this paper a five-level inverter structure is proposed for open-end winding induction motor (IM) drives, by cascading only two conventional two-level and three-level inverters, with the elimination of the common mode voltage over the entire modulation range. The DC link power supply requirement is also optimized by means of DC link capacitor voltage balancing, with PWM control., using only inverter switching state redundancies. The proposed power circuit gives a simple power bits structure.

Thermal polymerization of acrylamide in the solid state

The role of imperfections in thermal polymerization of acrylamide in the solid state was studied. The polymer yield and the degree of polymerization are highly dependent on the particle size and on the pressure to which the monomer is subjected prior to polymerization reaction. There is an enhancement in the rate of polymerization in air unlike in the case of radiation-induced polymerization. Thermal polymerization of acrylamide in pelletized form results in the formation of water-soluble linear polymer and water-insoluble cross-linked product with the evolution of ammonia. The activation energy (E) values obtained in the present investigation reveal that basically there are two processes taking place, one with E = 34–36 kcal/mole, corresponding to the initiation process, and the other with E = 19 ± 3 kcal/more for the propagation process.

Stereochemistry of Peptides Containing 1-AminocyclopentanecarboxylicA cid ( Am5): Solution and Solid-state Conformations of Boc-Acc '-Acc'-NHMe

The conformational analysis of a protected homodipeptide of 1-aminocyclopentanecarboxylic acid (Acc5) has been carried out. 1H-nmr studies establish a -turn conformation for Boc-Acc5-Acc5-NHMe in chloroform and dimethylsulfoxide solutions involving the methylamide NH in an intramolecular hydrogen bond. Supportive evidence for the formation of an intramolecular hydrogen bond is obtained from ir studies. X-ray diffraction studies reveal a type III -turn conformation in the solid state stabilized by a 4 1 hydrogen bond between the Boc CO and methylamide NH groups. The , values for both Acc5 residues are close to those expected for an ideal 310-helical conformation ( ± 60°, ±30°).