Minimal model for beta relaxation in viscous liquids

Contrasts between beta relaxation in equilibrium viscous liquids and glasses are rationalized in terms of a double-well potential model with structure-dependent asymmetry, assuming structure is described by a single order parameter. The model is tested for tripropylene glycol where it accounts for the hysteresis of the dielectric beta loss peak frequency and magnitude during cooling and reheating through the glass transition.Comment: Phys. Rev. Lett. (in press

Charge and momentum transfer in supercooled melts: Why should their relaxation times differ?

The steady state values of the viscosity and the intrinsic ionic-conductivity of quenched melts are computed, in terms of independently measurable quantities. The frequency dependence of the ac dielectric response is estimated. The discrepancy between the corresponding characteristic relaxation times is only apparent; it does not imply distinct mechanisms, but stems from the intrinsic barrier distribution for $\alpha$-relaxation in supercooled fluids and glasses. This type of intrinsic ``decoupling'' is argued not to exceed four orders in magnitude, for known glassformers. We explain the origin of the discrepancy between the stretching exponent $\beta$, as extracted from $\epsilon(\omega)$ and the dielectric modulus data. The actual width of the barrier distribution always grows with lowering the temperature. The contrary is an artifact of the large contribution of the dc-conductivity component to the modulus data. The methodology allows one to single out other contributions to the conductivity, as in ``superionic'' liquids or when charge carriers are delocalized, implying that in those systems, charge transfer does not require structural reconfiguration.Comment: submitted to J Chem Phy

Relation between the High Density Phase and the Very-High Density Phase of Amorphous Solid Water

It has been suggested that high-density amorphous (HDA) ice is a structurally arrested form of high-density liquid (HDL) water, while low-density amorphous (LDA) ice is a structurally arrested form of low-density liquid (LDL) water. Recent experiments and simulations have been interpreted to support the possibility of a second "distinct" high-density structural state, named very high-density amorphous (VHDA) ice, questioning the LDL-HDL hypothesis. We test this interpretation using extensive computer simulations, and find that VHDA is a more stable form of HDA and that in fact VHDA should be considered as the amorphous ice of the quenched HDL.Comment: 5 pages, 4 fig

PENGARUH CORPORATE GOVERNANCE TERHADAP VOLUNTARY AUDITOR SWITCHING (Studi Empiris pada Perusahaan Manufaktur, Perdagangan, Jasa, dan Investasi yang Terdaftar di Bursa Efek Indonesia pada Tahun 2009-2013)

This research aims to examine and obtain empirical evidence about the elements of corporate governance mechanism that affect the replacement of public accountant on a voluntary basis in Indonesia. This issue is important because the company raised given the freedom to choose the auditor and replace it outside the rules (mandatory). Independent variables that used in this research : managerial ownership, concentration of ownership, change of directors, the composition of the board of commissioners, audit committee size, and the number of audit committee meetings. The object of this research are firms on the sector of manufacturing, trade, services and investments listed in the Indonesian Stock Exchange during the five years (2009-2013) but for some variables needed data in previously. Data collection method used in this research is purposive sampling, based on predetermined criteria. A total of 45 companies per year, is used as sample company. Data were analyzed using logistic regression analysis. Results from this research showed that the concentration of ownership and the number of audit committee meetings per year, have a positive influence on voluntary auditor switching. The next result shows that managerial ownership and the size of the audit committee have a negative effect on voluntary auditor switching. While the other variables examined in this research as the change of the directors and the composition of the board of commissioners are not shown to have an influence on the company's decision to do voluntary auditor switching

Dielectric spectroscopy on aging glasses

In the present work, we provide further evidence for the applicability of a modified stretched-exponential behavior, proposed recently for the description of aging-time dependent data below the glass temperature [P. Lunkenheimer et al., Phys. Rev. Lett. 95 (2005) 055702]. We analyze time-dependent dielectric loss data in a variety of aging glasses, including new data on Salol and propylene carbonate, using a conventional stretched exponential and the newly proposed approach. Also the scaling of aging data obtained at different measuring frequencies, which was predicted on the basis of the new approach, is checked for its validity.Comment: 6 pages, 5 figures, submitted to proceedings of 5th IDMRCS, Lille, 200

Genetic Gains of Milk Yield and Milk Composition as Realized Response to Dairy Cow Selection in Bbptu-hpt Baturraden, Indonesia

The aims of this study were to estimate the heritabilities, examine the effects of dairy femaleselection and calculate the genetic gains on milk yield and milk composition in Baturraden Dairy CattleBreeding and Forage Centre (Balai Besar Perbibitan Ternak Unggul dan Hijauan Pakan Ternak /BBPTU–HPT Baturraden), Indonesia. The first lactation records of 221 dairy cows from 2006 to 2014were used. Heritabilities were estimated by paternal half-sib correlation. Comparison of averageperformances between daughter population (Ā) and initial dam population before selection ( ) wereconducted by Z-test. Annual genetic gain was calculated as genetic gain per generation (the differencesbetween Ā dan ) divided by generation interval. Heritabilities for milk fat percentage (FP), milk fatyield (FY), milk protein percentage (PP) and milk protein yield (PY) were 0.46, 0.30, 0.28 and 0.17,respectively. A significant increase (P=0.025) in the total milk yield (TMY) from the first generation(G1) to the second generation (G2) resulted in a high significant decrease in the FP (P=0.004). Geneticgains of TMY, FP and PP were 9.76 kg, -0.04% and -0.01% per year, respectively. It is concluded thatselection for higher TMY only negatively affect FP and PP. Selection can be applied based on FY to avoid the decrease of FP. Negative effects of genetic-environmental interaction resulted in slowergenetic gain because the imported cows needed time to adapt to the local environment

Structural influence on atomic hopping and electronic states of Pd-based bulk metallic glasses

Atomic motion and electronic structures of Pd–Ni–Cu–P bulk metallic glasses were investigated using 31P nuclear magnetic resonance. The hopping rate of P atoms was determined by the stimulated echo technique. Significant hopping was observed in all alloys well below the glass transition temperature. Increasing the Cu content to above 25 at. % increases P hopping significantly, consistent with the previous finding that the openness of the structure increases with Cu content. In contrast, P hopping is not influenced by changes of local electronic states at P sites, induced by the substitution of Ni by Cu