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Full-Text Articles in Engineering

Ultra Fast Mas Solid-State Nmr Studies Of Protein-Protein Interactions In The Bacterial Replisome, M Felletti, S Jehle, Y Wang, Kiyoshi Ozawa, S Jergic, G Otting, L Emsley, A Lesage, N Dixon, G Pintacuda Jul 2013

Ultra Fast Mas Solid-State Nmr Studies Of Protein-Protein Interactions In The Bacterial Replisome, M Felletti, S Jehle, Y Wang, Kiyoshi Ozawa, S Jergic, G Otting, L Emsley, A Lesage, N Dixon, G Pintacuda

Professor Nick E Dixon

Replication of genomic DNA in bacteria involves multiple stable and transient interactions among protein subunits constituting the replisome. Here we show how ultra-fast magic angle spinning (MAS) solid-state NMR (ssNMR) and 1H-detection on either deutereted or fully protonated samples, can give new information about protein-protein interactions in the E. coli replisome. We focused on two fundamental interactions: the first one between the C-terminal domain of the single-stranded (ss) DNA binding protein and its own DNA-binding site, and the second one between the DNA polymerase III subunits a and s. SSB (a tetramer of 79 kDa) has a structurally well-defined ssDNA …


Rotation Patterns And Trend Estimation For Repeated Surveys Using Rotation Group Estimates, Craig Mclaren, David Steel Jun 2013

Rotation Patterns And Trend Estimation For Repeated Surveys Using Rotation Group Estimates, Craig Mclaren, David Steel

Professor David Steel

A general approach for constructing filters to produce trend estimates from a repeated survey is described. This approach accounts for the correlation structure induced by the rotation pattern used in the survey. Different filters are developed depending on whether the trend analysis is based on elementary estimates available for each rotation group or overall estimates obtained by combining the rotation group estimates. The properties of trend estimates obtained directly from the elementary estimates, those obtained from the simple average of the rotation group estimates and trend estimates obtained from the best linear unbiased estimates of the population characteristics of interest …


Ignoring A Level In A Multilevel Model: Evidence From Uk Census Data, Mark Tramner, David Steel Jun 2013

Ignoring A Level In A Multilevel Model: Evidence From Uk Census Data, Mark Tramner, David Steel

Professor David Steel

Because of the inherent multilevel nature of census data, it is often appropriate to use multilevel models to investigate relationships between census variables. For a local population, the data available from the census allow a three-level nested model to be assumed, with an individual level (level 1), an enumeration district (ED) level (level 2), and a ward level (level 3). The consequences of ignoring one of the three levels in this model are assessed here theoretically. Empirical results, based on 1991 UK Census data, are also provided, comparing the variance components estimated from the three-level model with analyses based on …


The Impact Of Different Rotation Patterns On The Sampling Variance Of Seasonally Adjusted And Trend Estimates, Craig Mclaren, David Steel Jun 2013

The Impact Of Different Rotation Patterns On The Sampling Variance Of Seasonally Adjusted And Trend Estimates, Craig Mclaren, David Steel

Professor David Steel

Many economic and social time series are based on sample surveys which have complex sample designs. The sample design affects the properties of the time series. In particular, the overlap of the sample from period to period affects the variability of the time series of survey estimates, and the seasonally adjusted and trend estimates produced from them. The Census X11 and X11ARIMA packages are commonly used to produce seasonally adjusted estimates and can also be used to produce estimates of trend. This paper considers the implications of different overlap patterns on the sampling variance of seasonally adjusted and trend estimates …


An Evaluation Of A Large-Scale Cati Household Survey Using Random Digit Dialling, Don Bennett, David Steel Jun 2013

An Evaluation Of A Large-Scale Cati Household Survey Using Random Digit Dialling, Don Bennett, David Steel

Professor David Steel

omputer-assisted telephone interviewing and random digit dialling are increasingly being used to conduct household surveys in Australia. However, there is little published information concerning Australian experience with such surveys. In 1995 the Government Statistician's Office in Queensland conducted a household survey to study population migration using these techniques. The survey involved a sample of 110 000 telephone numbers resulting in 38 000 responding households. This article describes a computerized survey management system that was developed and which provided information concerning important operational and quality aspects of the survey.


Optimum Allocation Of Sample To Strata And Stages With Simple Additional Constraints, Robert Clark, David Steel Jun 2013

Optimum Allocation Of Sample To Strata And Stages With Simple Additional Constraints, Robert Clark, David Steel

Professor David Steel

The optimum allocation of a sample to strata and stages in a stratified two-stage design for a simple cost function is well known. In practice there may be reasons to impose simple additional constraints. It is shown how the theory for optimum allocation can be generalized to account for such constraints. A simple way of assessing the effect that each constraint has on the efficiency of the sample design is developed. This general approach allows several additional constraints that are used in practice to be applied. Data from the 1996 redesign of the Australian Monthly Labour Force Survey are used …


Statistical Indicators For Local Government Areas: A Case Study Of The Shoalhaven Lga, 1997, Nell Stetner-Houweling, David Steel, Greg Pullen Jun 2013

Statistical Indicators For Local Government Areas: A Case Study Of The Shoalhaven Lga, 1997, Nell Stetner-Houweling, David Steel, Greg Pullen

Professor David Steel

Decision makers and planers need to have relevant and reliable information to give a picture of how different areas are developing economically and socially. However, there is a perceived lack of timely and easily accessible data at the Local Government Area (LGA) level. This study produced a statistical profile of the Shoalhaven (LGA) by developing a conceptual framework, which represents the key economic, social, and population characteristics of the LGA. The statistical data available from the Australian Bureau of Statistics (ABS) at the level of the LGA, was investigated and summarised. Other sources of information available to create a statistical …


Restricted Quasi-Score Estimating Functions For Sample Survey Data, Yan Lin, David Steel, Raymond Chambers Jun 2013

Restricted Quasi-Score Estimating Functions For Sample Survey Data, Yan Lin, David Steel, Raymond Chambers

Professor David Steel

This paper applies the theory of the quasi-likelihood method to model-based inference for sample surveys. Currently, much of the theory related to sample surveys is based on the theory of maximum likelihood. The maximum likelihood approach is available only when the full probability structure of the survey data is known. However, this knowledge is rarely available in practice. Based on central limit theory, statisticians are often willing to accept the assumption that data have, say, a normal probability structure. However, such an assumption may not be reasonable in many situations in which sample surveys are used. We establish a framework …


Simple Methods For Ecological Inference In 2x2 Tables, Raymond Chambers, David Steel Jun 2013

Simple Methods For Ecological Inference In 2x2 Tables, Raymond Chambers, David Steel

Professor David Steel

This paper considers inference about the individual level relationship between two dichotomous variables based on aggregated data. It is known that such analyses suffer from 'ecological bias', caused by the lack of homogeneity of this relationship across the groups over which the aggregation occurs. Two new methods for overcoming this bias, one based on local smoothing and the other a simple semiparametric approach, are developed and evaluated. The local smoothing approach performs best when it is used with a covariate which accounts for some of the variation in the relationships across groups. The semiparametric approach performed well in our evaluation …


Multivariate Random Effect Models With Complete And Incomplete Data, James Chipperfield, David Steel Jun 2013

Multivariate Random Effect Models With Complete And Incomplete Data, James Chipperfield, David Steel

Professor David Steel

No abstract provided.


The Effect Of Different Rotation Patterns On The Revisions Of Trend Estimates, David G. Steel, Craig H. Mclaren Jun 2013

The Effect Of Different Rotation Patterns On The Revisions Of Trend Estimates, David G. Steel, Craig H. Mclaren

Professor David Steel

The X11 and X11ARIMA procedures are widely used to produce seasonally adjusted and trend estimates from time series obtained from sample surveys. The surveys are often based on designs in which there is sample overlap between different periods. The degree of overlap is determined by the pattern of inclusion of selected units over time, i.e., the rotation pattern. An important issue in analysing the series is that trend estimates at the end of the series are revised as estimates for recent periods are added. This article considers the effects of different rotation patterns on the mean squared error of the …


On The Growth Mechanisms Of Thin Films Produced By Pulsed Laser Deposition, J Mckinnon, Mihail Ionescu, Dongqi Shi, S. X. Dou Jun 2013

On The Growth Mechanisms Of Thin Films Produced By Pulsed Laser Deposition, J Mckinnon, Mihail Ionescu, Dongqi Shi, S. X. Dou

Shi Xue Dou

For more than ten years Pulsed Laser Deposition (PLD) has been used to produce Y1Ba2CU3O7-8 (YBCO) thin films. Most groups have reported their capacity to produce films with roughly optimum characteristics. Unfortunately, the deposition parameters used by the individual groups vruy within broad limits [1-5]. Each group develops a similar but unique recipe of deposition parameters, which, combined with other system specific characteristics, optimises their film properties. The implication of this is that the set of parameters being reported is not the whole story. In this paper we put forward a set of generally accepted facts about the PLD process …


Relationship Between Orientation Of Ceo2 Films And Surface Morphology, Dongqi Shi, Mihail Ionescu, Jeff Mckinnon, Wu Ming Chen, S. X. Dou Jun 2013

Relationship Between Orientation Of Ceo2 Films And Surface Morphology, Dongqi Shi, Mihail Ionescu, Jeff Mckinnon, Wu Ming Chen, S. X. Dou

Shi Xue Dou

Pure c-axis orientation CeO2 films were deposited on YSZsingle crystal substrates_ by pulse laser deposition (PLD) in oxygen. The optimum epitaxial growth temperature for a high level of c-axis orientation is 7900 C, and it is related to the morphology of CeO2 grains. The more circular the shape of the grains is, the better the caxis orientation and the smoothness of CeO2 film surface are. This correlation appears to be an intrinsic feature of CeO2 growth, independent of the type of substrate or the deposition method. Also it was found that the topography of the film surface grown by PLD …


Research Of Surface-Oxidation Epitaxy Of Nio Films On Cube Textured Ni Tapes, Dongqi Shi, Mihail Ionescu, Jeff Mckinnon, Wu Ming Chen, S. X. Dou Jun 2013

Research Of Surface-Oxidation Epitaxy Of Nio Films On Cube Textured Ni Tapes, Dongqi Shi, Mihail Ionescu, Jeff Mckinnon, Wu Ming Chen, S. X. Dou

Shi Xue Dou

Thin films of NiO were fabricated in air by surface-oxidation epitaxy (SOE) on biaxially-textured Ni substrate, for use as buffer layers for YBCO coated conductors. The surface-oxidation conditions such as the temperature and the reaction time, as well as the cooling rate, playa determining role in the process of epitaxial growth of the NiO layer. A continuous, biaxially-aligned textured NiO layer, was obtained for a 10 min oxidation in air at 1120°C,and acooling rate of 150 Klh. The roughness of the NiO layer is mostly controlled by a coarsening of some NiO grains .


Visualization Of Vortex Motion In Feas-Based Bafe1.9ni0.1as2 Single Crystal By Means Of Magneto-Optical Imaging, Zhi W. Lin, Yong Jian Li, Jian G. Zhu, Xiaolin Wang, S. X. Dou, Youguang Guo, Gang Lei, Yi Wang, Matthew Philips, Michael Cortie, Yan-Cheng Li, Ki-Young Choi, Xun Shi Jun 2013

Visualization Of Vortex Motion In Feas-Based Bafe1.9ni0.1as2 Single Crystal By Means Of Magneto-Optical Imaging, Zhi W. Lin, Yong Jian Li, Jian G. Zhu, Xiaolin Wang, S. X. Dou, Youguang Guo, Gang Lei, Yi Wang, Matthew Philips, Michael Cortie, Yan-Cheng Li, Ki-Young Choi, Xun Shi

Shi Xue Dou

Superconductivity has been found in newly discovered iron-based compounds. This paper studies the motion of magnetic vortices in BaFe1.9Ni0.1As2 single crystal by means of the magneto-optical imaging technique. A series of magneto-optical images reflecting magnetic flux distribution at the crystal surface were taken when the crystal was zero-field cooled to 10 K. The behavior of the vortices, including penetration into and expulsion from the single crystal with increasing and decreasing external fields, respectively, is discussed. The motion behavior is similar to that observed in high-Tc superconducting cuprates with strong vortex pinning; however, the …


Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou Jun 2013

Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou

Shi Xue Dou

Flexible silicon/single-walled carbon nanotube (Si/SWCNT) composite paper was prepared using the pulsed laser deposition (PLD) method to deposit Si onto SWCNT paper. In the composite, Si mainly shows nanoworm-like morphology. Increasing deposition time results in an increased amount of Si microspheres. Electrochemical measurements show that the capacity of the composite paper is improved by the presence of Si. The Si/SWCNT composite with only 2.2% Si shows a capacity of 163 mA h g−1 at a current density of 25 mA g−1 up to 50 cycles, which is more than 60% improvement of the capacity of pristine CNT paper. The Si …


Orbital Structure Of Fetio3 Ilmenite Investigated With Polarization-Dependent X-Ray Absorption Spectroscopy And Band Structure Calculations, S W. Chen, M J. Huang, P A. Lin, H T. Jeng, J M. Lee, S C. Haw, S A. Chen, H J. Lin, K T. Lu, Dapeng Chen, S X. Dou, X L. Wang, J M. Chen Jun 2013

Orbital Structure Of Fetio3 Ilmenite Investigated With Polarization-Dependent X-Ray Absorption Spectroscopy And Band Structure Calculations, S W. Chen, M J. Huang, P A. Lin, H T. Jeng, J M. Lee, S C. Haw, S A. Chen, H J. Lin, K T. Lu, Dapeng Chen, S X. Dou, X L. Wang, J M. Chen

Shi Xue Dou

We explored the orbital structure of FeTiO3 with polarization-dependent x-ray absorption spectra complemented with electronic structure calculations. The electronic structure, near the bottom of conduction band, is composed of O 2p and Ti 3d orbitals. Ti 3d/4p hybridization dominantly lies on the ab plane. The highly delocalized Ti 4p orbital might hybridize with O 2p orbital and even extend to the next-neighbor Fe atom whereby establishing a linear orbital combination of Ti-O-Fe. A clear picture of the orbital construction in FeTiO3 will help to elucidate the paths of pressure-induced charge transfer and other physical or magnetic characteristics.


Re-Entrant Ferromagnet Prmn2ge0.8si1.2: Magnetocaloric Effect, S X. Dou, Jianli Wang, Rong Zeng, Chung-Kiak Poh, Stewart J. Campbell, S J. Kennedy Jun 2013

Re-Entrant Ferromagnet Prmn2ge0.8si1.2: Magnetocaloric Effect, S X. Dou, Jianli Wang, Rong Zeng, Chung-Kiak Poh, Stewart J. Campbell, S J. Kennedy

Shi Xue Dou

The structural and magnetic properties of the re-entrant ferromagnet PrMn2Ge0.8Si1.2 have been investigated by various experimental methods. Similar to the canonical re-entrant ferromagnet SmMn2Ge2, multiple magnetic phase transitions have been detected in PrMn2Ge0.8Si1.2 over the temperature range from 10 to 550 K with re-entrant ferromagnetism occurring around ∼ 54 K. The magnetocaloric effect has been measured in terms of the isothermal magnetocaloric entropy change and found to be positive at the re-entrant ferromagnetic transition with a maximum value of around 1.9 J/kg K at 58 K for a magnetic field change of 0–3 T. On the other hand, the entropy …


Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura Jun 2013

Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura

Shi Xue Dou

Single phase Bi2FeMnO6 was synthesized on Si substrates by an electrospray method. Three peaks were observed in the temperature dependence of magnetization curve, which is attributed to the inhomogeneous distribution of Fe3+ and Mn3+. The observed magnetic peaks at 150 K, 260 K, and 440 K correspond to orderings of the ferrimagnetic Fe–O–Mn, and antiferromagnetic Mn–O–Mn and Fe–O–Fe, respectively. Heat capacity measurements were carried out to confirm these magnetic transitions. The Debye temperature of Bi2FeMnO6 is 339 K, calculated from Debye–Einstein fitting.


The Effects Of Annealing Temperature On The In-Field Jc And Surface Pinning In Silicone Oil Doped Mgb2 Bulks And Wires, M S. Hossain, A Motaman, O Cicek, H Agil, E Ertekin, A Gencer, Xiaolin Wang, S X. Dou Jun 2013

The Effects Of Annealing Temperature On The In-Field Jc And Surface Pinning In Silicone Oil Doped Mgb2 Bulks And Wires, M S. Hossain, A Motaman, O Cicek, H Agil, E Ertekin, A Gencer, Xiaolin Wang, S X. Dou

Shi Xue Dou

No abstract provided.


Magnetic Phase Transition And Mossbauer Spectroscopy Of Erni2mnx Compounds, Jianli Wang, S J. Campbell, R Zeng, S. X. Dou, S J. Kennedy Jun 2013

Magnetic Phase Transition And Mossbauer Spectroscopy Of Erni2mnx Compounds, Jianli Wang, S J. Campbell, R Zeng, S. X. Dou, S J. Kennedy

Shi Xue Dou

Investigation of ErNi2Mnx with 0.90 ≤ x ≤ 1.10 indicates that the MgCu2-type structure (with space group Fd-3m) is formed within x = 0.97−1.10. Curie temperature TC = 50 K of ErNi2Mn is significantly higher than those of the corresponding ErNi2 (TC = 7 K) and ErMn2 (TC  = 15 K) compounds. Detailed analyses of DC magnetization data demonstrate that the magnetic phase transition at the Curie temperature is second order. The magnetic entropy change around TC has been found to be 4.8 J/kg K for a magnetic field change of 0 to 5 T with its relative cooling power …


Apparent Negative Mobility Of Vortex Matter Due To Inhomogeneous Pinning, X B Xu, H Fangohr, Shichao Ding, M Gu, T.B Tang, Z Han, Dongqi Shi, S X. Dou Jun 2013

Apparent Negative Mobility Of Vortex Matter Due To Inhomogeneous Pinning, X B Xu, H Fangohr, Shichao Ding, M Gu, T.B Tang, Z Han, Dongqi Shi, S X. Dou

Shi Xue Dou

We investigate the transport of vortices in superconductors with inhomogeneous pinning under a driving force. The inhomogeneity of pinning is simplified as strong-weak pinning regions. It is demonstrated that the interactions between the vortices captured by strong pinning potentials and the vortices in the weak pinning region cause absolute negative motion (ANM) of vortices: The vortices which are climbing toward the high barriers induced by the strong pinning with the help of driving force move toward the opposite direction of the force and back to their equilibrium positions in the weak pinning region as the force decreases or is withdrawn. …


A Significant Improvement In The Superconducting Properties Of Mgb2 By Co-Doping With Graphene And Nano-Sic, K S B De Silva, X Xu, Xiaolin Wang, D Wexler, D Attard, F Xiang, S. X. Dou Jun 2013

A Significant Improvement In The Superconducting Properties Of Mgb2 By Co-Doping With Graphene And Nano-Sic, K S B De Silva, X Xu, Xiaolin Wang, D Wexler, D Attard, F Xiang, S. X. Dou

Shi Xue Dou

The effects of graphene (G) and nanosilicon carbide (SiC) co-doping on the superconducting properties of MgB2 were studied using bulk samples. SiC remains one of the best dopants which can significantly improve the high field performance, while graphene is emerging as a new dopant for MgB2, which can improve the zero field critical current density (Jc). The superconducting properties characterized by Jc, the intergrain connectivity, and the critical fields were significantly improved by the use of both SiC and graphene as dopants.


Flux Distribution In Fe-Based Superconducting Materials By Magneto-Optical Imaging, Zhi Wei Lin, Jian Guo Zhu, You Guang Guo, Xiaolin Wang, S X. Dou, Tom H. Johansen, Xun Shi, K Y. Choi Jun 2013

Flux Distribution In Fe-Based Superconducting Materials By Magneto-Optical Imaging, Zhi Wei Lin, Jian Guo Zhu, You Guang Guo, Xiaolin Wang, S X. Dou, Tom H. Johansen, Xun Shi, K Y. Choi

Shi Xue Dou

"This paper presents the magnetic flux distributions in Fe-based superconducting materials including single crystal of Ba(Fe1.9Ni0.1)As2 and Ba(Fe1.8Co0.2)As2, as well as polycrystalline SmFeO0.75F0.2As by means of magneto-optical imaging (MOI) technique. The single crystals were grown out of FeAs flux while polycrystalline sample was grown by hot-press. A MOI film with in-plan magnetization was used to visualize flux distributions at the sample surface. A series of magneto-optical images was taken when the samples were zero-field cooled and field cooled. The flux behavior, including penetration into and expelling from the samples, as well as pinning properties were studied. When external fields increase, …


Anisotropic And Excellent Magnetocaloric Properties Of La 0.7ca0.3mno3 Single Crystal With Anomalous Magnetization, J.C Debnath, Rong Zeng, Jung Ho Kim, Dapeng Chen, S X. Dou Jun 2013

Anisotropic And Excellent Magnetocaloric Properties Of La 0.7ca0.3mno3 Single Crystal With Anomalous Magnetization, J.C Debnath, Rong Zeng, Jung Ho Kim, Dapeng Chen, S X. Dou

Shi Xue Dou

Magnetic properties and the magnetocaloric effect (MCE) have been investigated in La0.7Ca0.3MnO3 single crystal with applied field along both the ab-plane and the c-direction. Due to the magnetocrystalline anisotropy, the crystal exhibits anisotropy in the MCE. Upon application of a 5 T field, the magnetic entropy changes (SM), reaching values of 7.668 J/(kg K) and 6.412 J/(kg K) for both the ab-plane and the c-direction, respectively. A magnetic entropy change of 3.3 J/(kg K) was achieved for a magnetic field change of 1.5 T at the Curie temperature, TC = 245 K. Due to the absence of grains in the …


Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou Jun 2013

Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou

Shi Xue Dou

Lanthanum doped multiferroic DyFeO3 was synthesized by solid state reaction. X-ray diffraction and refinement show that the lattice parameters of Dy1−xLaxFeO3 increase linearly with the La content. Raman spectroscopy reveals that the short-range force constant in Dy1−xLaxFeO3 is decreased by La3+ ion substitution. The spin reorientation phase transition temperature (TSRPT) is observed to decrease along with the doping level. The antiferromagnetic ordering temperature TN of Fe3+ ions is depressed with increasing doping level. Both decreasing TSRPT and decreasing TN indicate that Fe–Dy and Fe–Fe interactions are weakened by La substitution. It is found that the electron configuration of Fe3+ is …


Facile Synthesis Of A Interleaved Expanded Graphite-Embedded Sulphur Nanocomposite As Cathode Of Li-S Batteries With Excellent Lithium Storage Performance, Yun-Xiao Wang, Ling Huang, Li-Chao Sun, Su-Yuan Xie, Gui-Liang Xu, Shu-Ru Chen, Yue-Feng Xu, Jun-Tiao Li, Shulei Chou, S. X. Dou, Shi-Gang Sun Jun 2013

Facile Synthesis Of A Interleaved Expanded Graphite-Embedded Sulphur Nanocomposite As Cathode Of Li-S Batteries With Excellent Lithium Storage Performance, Yun-Xiao Wang, Ling Huang, Li-Chao Sun, Su-Yuan Xie, Gui-Liang Xu, Shu-Ru Chen, Yue-Feng Xu, Jun-Tiao Li, Shulei Chou, S. X. Dou, Shi-Gang Sun

Shi Xue Dou

This paper reports the facile synthesis of a unique interleaved expanded graphite-embedded sulphur nanocomposite (S-EG) by melt-diffusion strategy. The SEM images of the S-EG materials indicate the nanocomposites consist of nanosheets with a layer-by-layer structure. Electrochemical tests reveal that the nanocomposite with a sulphur content of 60% (0.6S-EG) can deliver the highest discharge capacity of 1210.4 mAh g−1 at a charge–discharge rate of 280 mA g−1 in the first cycle, the discharge capacity of the 0.6S-EG remains as high as 957.9 mAh g−1 after 50 cycles of charge–discharge. Furthermore, at a much higher charge–discharge rate of 28 A g−1, the …


The Control Of Time-Dependent Buckling Patterns In Thin Confined Elastomer Film, Brad Winton, Mihail Ionescu, S X. Dou Jun 2013

The Control Of Time-Dependent Buckling Patterns In Thin Confined Elastomer Film, Brad Winton, Mihail Ionescu, S X. Dou

Shi Xue Dou

Low energy metal ion implantation has been used to combine an easy “bottom-up” way of creating and tuning different topographic structures on submicron to micrometer scales with the embedding of a metallic element-rich functionalized layer at the surface for a variety of scientific and technological applications. The self-organizing and complex patterns of functionalized topographic structures are highly dependent on the implanted metal ion species, variations in the geometric confinement of the buckled areas on the larger unmodified elastomer film, and the boundary conditions of the buckled regions. Systematic investigations of these dependencies have been carried out via optical and atomic …


Zero-Gap Materials For Future Spintronics, Electronics And Optics, Xiaolin Wang, S X. Dou, Chao Zhang Jun 2013

Zero-Gap Materials For Future Spintronics, Electronics And Optics, Xiaolin Wang, S X. Dou, Chao Zhang

Shi Xue Dou

Electrons carry both charge and spin. The processing of information in conventional electronic devices is based only on the charge of the electrons. Spin electronics, or spintronics, uses the spin of electrons, as well as their charge, to process information. Metals, semiconductors and insulators are the basic materials that constitute the components of electronic devices, and these have been transforming all aspects of society for over a century. In contrast, magnetic metals, half-metals, magnetic semiconductors, dilute magnetic semiconductors and magnetic insulators are the materials that will form the basis for spintronic devices. Materials having a zero-energy band gap are a …


In-Field Jc Improvement By Oxygen-Free Pyrene Gas Diffusion Into Highly Dense Mgb2 Superconductor, Minoru Maeda, Jung Ho Kim, Y Zhao, Yoon-Uk Heo, K Takase, Y Kubota, C Moriyoshi, F Yoshida, Y Kuroiwa, S X. Dou Jun 2013

In-Field Jc Improvement By Oxygen-Free Pyrene Gas Diffusion Into Highly Dense Mgb2 Superconductor, Minoru Maeda, Jung Ho Kim, Y Zhao, Yoon-Uk Heo, K Takase, Y Kubota, C Moriyoshi, F Yoshida, Y Kuroiwa, S X. Dou

Shi Xue Dou

Oxygen-free pyrene gas as a carbon (C) dopant was delinked and incorporated into highly dense MgB2 structure via a gas phase diffusion method. The technique offers the advantages that molecular C is homogeneously distributed into MgB2 and substituted at the boron sites without any severe deterioration of grain connectivity. The C substitution causes a significant shrinkage of the a-lattice parameter and an increase in the lattice strain, resulting in high disorder. The introduction of structural disorder as a result of C doping leads to a considerable enhancement of the in-field critical current density (Jc) and upper critical field.