376 research outputs found
Intrinsic carrier mobility of multi-layered MoS field-effect transistors on SiO
By fabricating and characterizing multi-layered MoS-based field-effect
transistors (FETs) in a four terminal configuration, we demonstrate that the
two terminal-configurations tend to underestimate the carrier mobility
due to the Schottky barriers at the contacts. For a back-gated two-terminal
configuration we observe mobilities as high as 125 cmVs which
is considerably smaller than 306.5 cmVs as extracted from the
same device when using a four-terminal configuration. This indicates that the
intrinsic mobility of MoS on SiO is significantly larger than the
values previously reported, and provides a quantitative method to evaluate the
charge transport through the contacts.Comment: 8 pages, 5 figures, typos fixed, and references update
Investigation of the AODV and the SDWCA QoS handling at different utilisation levels in adaptive clustering environments
A simulation study using NS2 simulator using two main routing protocols with specific design parameters has been carried out to investigate the QoS main parameters such as throughput, delay, Jitter, Control Overhead, Number of packets, number of packets dropped and the rating overheads. The traffic is made of CBR slow video traffic. From the result it is noted that the SDWCA routing protocol outperforms the AODV routing protocols in the throughput, the delay and the jitter issues at different loading levels
Growth of carbon nanotubes on quasicrystalline alloys
We report on the synthesis of carbon nanotubes on quasicrystalline alloys.
Aligned multiwalled carbon nanotubes (MWNTs) on the conducting faces of
decagonal quasicrystals were synthesized using floating catalyst chemical vapor
deposition. The alignment of the nanotubes was found perpendicular to the
decagonal faces of the quasicrystals. A comparison between the growth and tube
quality has also been made between tubes grown on various quasicrystalline and
SiO2 substrates. While a significant MWNT growth was observed on decagonal
quasicrystalline substrate, there was no significant growth observed on
icosahedral quasicrystalline substrate. Raman spectroscopy and high resolution
transmission electron microscopy (HRTEM) results show high crystalline nature
of the nanotubes. Presence of continuous iron filled core in the nanotubes
grown on these substrates was also observed, which is typically not seen in
MWNTs grown using similar process on silicon and/or silicon dioxide substrates.
The study has important implications for understanding the growth mechanism of
MWNTs on conducting substrates which have potential applications as heat sinks
Is the Fate of Clinical Candidate Arry-520 Already Sealed? Predicting Resistance in Eg5–Inhibitor Complexes
Arry-520 is an advanced drug candidate from the Eg5 inhibitor class undergoing clinical evaluation in patients with relapsed or refractory multiple myeloma. Here we show by structural analysis that Arry-520 binds stoichiometrically to the motor domain of Eg5 in the conventional allosteric loop L5 pocket in a complex that suggests the same structural mechanism as other Eg5 inhibitors. We have previously shown that acquired resistance through mutations in the allosteric binding site located at loop L5 in the Eg5 structure appears to be independent of the inhibitors' scaffold, which suggests that Arry-520 will ultimately have the same fate. When Arry-520 was assessed in two cell lines selected for the expression of either Eg5(D130A) or Eg5(L214A) STLC-resistant alleles, mutations previously shown to convey resistance to this class of inhibitors, it was inactive in both. Surprisingly, when the cells were challenged with ispinesib, another Eg5 inhibitor, the Eg5(D130A) cells were resistant, but those expressing Eg5(L214A) were strikingly sensitive. Molecular dynamics simulations suggest that subtle differences in ligand binding and flexibility in both compound and protein may alter allosteric transmission from the loop L5 site that do not necessarily result in reduced inhibitory activity in mutated Eg5 structures. Whilst we predict that cells challenged with Arry-520 in the clinical setting are likely to acquire resistance through point mutations in the Eg5 binding site, the data for ispinesib suggests that this resistance mechanism is not scaffold independent as previously thought, and new inhibitors can be designed that retain inhibitory activity in these resistant cells
Design, 3D printing and validation of a novel low-cost high-capacity sitting-drop bridge for protein crystallization
Sitting drop protein crystallization is not used as commonly as the hanging drop
method for crystal optimization due to the limitations of commercially available sitting
drop bridges, particularly when they are used in conjunction with 24-well
crystallization plates. The commercially available sitting drop bridge, containing
space for only a single drop, restricts their wider use. Proteins that preferentially
crystallize under sitting-drop conditions therefore require more work, time and
resources for their optimization. As a result of these limitations and using 3D-printing,
we designed and developed a new sitting drop bridge where five crystallization drops
can be placed simultaneously in each well of a 24-well crystallization plate. This
significantly simplifies and increases the potential of sitting drops in crystal
optimization, reducing costs and hence overcomes existing limitations of current
approaches
Real-time Atomistic Observation of Structural Phase Transformations in Individual Hafnia Nanorods
High-temperature phases of hafnium dioxide have exceptionally high dielectric constants and large bandgaps, but quenching them to room temperature remains a challenge. Scaling the bulk form to nanocrystals, while successful in stabilizing the tetragonal phase of isomorphous ZrO2, has produced nanorods with a twinned version of the room temperature monoclinic phase in HfO2. Here we use in situ heating in a scanning transmission electron microscope to observe the transformation of an HfO2 nanorod from monoclinic to tetragonal, with a transformation temperature suppressed by over 1000°C from bulk. When the nanorod is annealed, we observe with atomic-scale resolution the transformation from twinned-monoclinic to tetragonal, starting at a twin boundary and propagating via coherent transformation dislocation; the nanorod is reduced to hafnium on cooling. Unlike the bulk displacive transition, nanoscale size-confinement enables us to manipulate the transformation mechanism, and we observe discrete nucleation events and sigmoidal nucleation and growth kinetics
Unleashing the potential of the TQM and Industry 4.0 to achieve sustainability performance in the context of a developing country
Business organizations may be able to improve their sustainability performance (SP) by adopting Total Quality Management (TQM) concepts combined with Industry 4.0 (I4.0) technologies. This research has developed a model to investigate the influence of TQM and I4.0 on SP. It also analyzes the mediating role of TQM in the relationship between I4.0 and SP. A survey was conducted among 240 respondents employed in ready-made garment (RMG) industries in Bangladesh. A Structural Equation Modelling (SEM) technique was used to analyze the collected data. Research findings show that both TQM and I4.0 technologies have a significant impact on the sustainable growth of the Bangladeshi RMG sector. Moreover, it is observed that TQM mediates the relationship between I4.0 and SP. The findings show that TQM helps to explain the relationship between I4.0 and sustainable performance. This study will provide a guideline for industrial executives on securing sustainability through the adoption of TQM concepts and I4.0 technologies. We are not aware of any additional studies that look at the possible link between TQM, I4.0, and SP, as well as the mediating role of TQM between I4.0 and SP
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