Examining research productivity of Chinese TEFL academics across departments and institutes

This study aims to benchmark Chinese TEFL academics’ research productivities, as a way to identify and, subsequently, address research productivity issues. This study investigated 182 Chinese TEFL academics’ research outputs and perceptions about research across three Chinese higher education institutions using a literature-based survey. ANOVA, t-tests and descriptive statistics were used to analyse data from and between the three institutions. Findings indicated that more than 70% of the TEFL academics had produced no research in 10 of the 12 research output fields during 2004-2008. The English Language and Literature Department in the national university outperformed all other departments at the three institutes for most of the research output categories. While a majority of the participants seemed to hold positive perceptions about research, t-tests and ANOVA indicated that their research perceptions were significantly different across institutes and departments. Developing TEFL research capacity requires tertiary institutions to provide research-learning opportunities

Comparison of alternatives to amplitude thresholding for onset detection of acoustic emission signals

Acoustic Emission (AE) monitoring can be used to detect the presence of damage as well as determine its location in Structural Health Monitoring (SHM) applications. Information on the time difference of the signal generated by the damage event arriving at different sensors in an array is essential in performing localisation. Currently, this is determined using a fixed threshold which is particularly prone to errors when not set to optimal values. This paper presents three new methods for determining the onset of AE signals without the need for a predetermined threshold. The performance of the techniques is evaluated using AE signals generated during fatigue crack growth and compared to the established Akaike Information Criterion (AIC) and fixed threshold methods. It was found that the 1D location accuracy of the new methods was within the range of <1–7.1%<1–7.1% of the monitored region compared to 2.7% for the AIC method and a range of 1.8–9.4% for the conventional Fixed Threshold method at different threshold levels

On the hydrodynamics of swimming enzymes

Several recent experiments suggest that rather generally the diffusion of enzymes may be augmented through their activity. We demonstrate that such swimming motility can emerge from the interplay between the enzyme energy landscape and the hydrodynamic coupling of the enzyme to its environment. Swimming thus occurs during the transit time of a transient allosteric change. We estimate the velocity during the transition. The analysis of such a swimming motion suggests the final stroke size is limited by the hydrodynamic size of the enzyme. This limit is quite a bit smaller than the values that can be inferred from the recent experiments. We also show that one proposed explanation of the experiments based on reaction heat effects can be ruled out using an extended hydrodynamic analysis. These results lead us to propose an alternate explanation of the fluorescence correlation measurements

Tunneling dynamics of side chains and defects in proteins, polymer glasses, and OH-doped network glasses

Simulations on a Lennard-Jones computer glass are performed to study effects arising from defects in glasses at low temperatures. The numerical analysis reveals that already a low concentration of defects may dramatically change the low temperature properties by giving rise to extrinsic double-well potentials (DWP's). The main characteristics of these extrinsic DWP's are (i) high barrier heights, (ii) high probability that a defect is indeed connected with an extrinsic DWP, (iii) highly localized dynamics around this defect, and (iv) smaller deformation potential coupling to phonons. Designing an extension of the Standard Tunneling Model (STM) which parametrizes this picture and comparing with ultrasound experiments on the wet network glass $a$-B$_2$O$_3$ shows that effects of OH-impurities are accurately accounted for. This model is then applied to organic polymer glasses and proteins. It is suggested that side groups may act similarly like doped impurities inasmuch as extrinsic DWP's are induced, which possess a distribution of barriers peaked around a high barrier height. This compares with the structurlessly distributed barrier heights of the intrinsic DWP's, which are associated with the backbone dynamics. It is shown that this picture is consistent with elastic measurements on polymers, and can explain anomalous nonlogarithmic line broadening recently observed in hole burning experiments in PMMA.Comment: 34 pages, Revtex, 9 eps-figures, accepted for publication in J. Chem. Phy

Nanoporous biocarbon as a storage system for methane

Abstract only availableActivated carbon produced from waste corn cobs have recently been developed as an efficient and economical form of gas storage. With rising gas prices and concerns of global warming, natural gas has been brought to attention as an alternative to gas and diesel. Activated carbons are capable of storing natural gas at low pressures and safe lengths of time via gas adsorption. Van der Waals interactions between methane gas molecules and the carbon solid forces the methane into a supercritical fluid that adsorbs onto surface of the solid. Methane uptake is assessed gravimetrically with steel sample cells. Masses are calibrated to correct for the effects due to air buoyancy. Data collected through methane isotherms, techniques of solid state NMR, and small-angle scattering reveal the pore structures and distribution of various carbon samples. The optimal pore size can be determined by executing methane isotherms at varying pressures between 25 and 500 psi. Ultimately, the same advances will be performed with hydrogen gas in exploring solutions and improvements to the gas crisis.U.S. Department of Energy Alliance for Collaborative Research in Alternative Fuel Technolog

Cd-111 and Cd-113 Spin-Lattice Relaxation in CdMoO4 By Paramagnetic Centers in the Absence of Spin Diffusion

In an ongoing effort to understand the solid-state spin-lattice relaxation mechanism and its modulation for heavy-nuclei spin-1/2 systems like Pb-207 and Tl-203/Tl-205, we have serendipitously observed that the recovery of a saturated Cd-111 (or Cd-113) nuclear magnetization in CdMoO4 shows the three distinct time regions elucidated by Bodart [Phys. Rev. B 54, 15291 (1996)] when nuclear-spin relaxation is dominated by paramagnetic impurity relaxation in the complete absence of nuclear-spin diffusion

Cd-111 and Cd-113 Spin-Lattice Relaxation in CdMoO4 By Paramagnetic Centers in the Absence of Spin Diffusion

In an ongoing effort to understand the solid-state spin-lattice relaxation mechanism and its modulation for heavy-nuclei spin-1/2 systems like Pb-207 and Tl-203/Tl-205, we have serendipitously observed that the recovery of a saturated Cd-111 (or Cd-113) nuclear magnetization in CdMoO4 shows the three distinct time regions elucidated by Bodart [Phys. Rev. B 54, 15291 (1996)] when nuclear-spin relaxation is dominated by paramagnetic impurity relaxation in the complete absence of nuclear-spin diffusion