845 research outputs found
Spontaneous synchronization of two bistable pyridine-furan nanosprings connected by an oligomeric bridge
The intensive development of nanodevices acting as two-state systems has
motivated the search for nanoscale molecular structures whose long-term
conformational dynamics are similar to the dynamics of bistable mechanical
systems such as Euler arches and Duffing oscillators. Collective synchrony in
bistable dynamics of molecular-sized systems has attracted immense attention as
a potential pathway to amplify the output signals of molecular nanodevices.
Recently, pyridin-furan oligomers of helical shape that are a few nanometers in
size and exhibit bistable dynamics similar to a Duffing oscillator have been
identified through molecular dynamics simulations. In this article, we present
the case of dynamical synchronization of these bistable systems. We show that
two pyridine-furan springs connected by a rigid oligomeric bridge spontaneously
synchronize vibrations and stochastic resonance enhances the synchronization
effect
A review of carbon fiber materials in automotive industry
In present scenario, light weighting becomes a main issue for energy efficiency in automotive industry. The emission of gases and fuel efficiency of vehicles are two important issues. The best way to improve the fuel efficiency is to decrease the weight of vehicle parts. Research and development played an important role in lightweight materials for decreasing cost, increasing ability to be recycled, enabling their integration into vehicles, and maximizing their fuel economy efficacy. There arises a need for developing a novel generation of materials that will combine both weight reduction and safety issues. The application of carbon fibre reinforced plastic material offers the best lightweight potential to realize lightweight concepts. Carbon fibre reinforced plastic has outstanding specific stiffness, specific strength, and fatigue properties compared to commonly used metals. In automotive industry, the advantages of carbon fibre reinforced plastic are reduction in weight, part integration and reduction, crashworthiness, durability, toughness, and aesthetic appealing. Carbon fibre reinforced plastic is a composite material that has been used extensively in various applications such as aerospace industry, sports equipment, oil and gas industry, and automotive industry. Keeping in view the aforementioned advantages of carbon fibre reinforced plastic, the authors have presented a brief review on carbon fibre for automotive industrial applications. Š Published under licence by IOP Publishing Ltd
Spontaneous Vibrations and Stochastic Resonance of Short Oligomeric Springs
There is growing interest in molecular structures that exhibit dynamics
similar to bistable mechanical systems. These structures have the potential to
be used as nanodevices with two distinct states. Particularly intriguing are
structures that display spontaneous vibrations and stochastic resonance.
Previously, through molecular dynamics simulations, it was discovered that
short pyridine-furan springs, when subjected to force loading, exhibit the
bistable dynamics of a Duffing oscillator. In this study, we extend these
simulations to include short pyridine-pyrrole and pyridine-furan springs in a
hydrophobic solvent. Our findings demonstrate that these systems also display
the bistable dynamics of a Duffing oscillator, accompanied by spontaneous
vibrations and stochastic resonance activated by thermal noise.Comment: arXiv admin note: substantial text overlap with arXiv:2110.0409
Static and resonant properties of decorated square kagome lattice compound KCu(TeO)(SO)Cl
The magnetic subsystem of nabokoite, KCu(TeO)(SO)Cl, is
constituted by buckled square kagome lattice of copper decorated by
quasi-isolated Cu ions. This combination determines peculiar physical
properties of this compound evidenced in electron spin resonance (ESR)
spectroscopy, dielectric permittivity , magnetization and
specific heat measurements. At lowering temperature, the magnetic
susceptibility passes through broad hump at about 150 K inherent
for low-dimensional magnetic systems and evidences sharp peak at
antiferromagnetic phase transition at K. The curve also
exhibits sharp peak at readily suppressed by magnetic field and
additional peak-like anomaly at K robust to magnetic
field. The latter can be ascribed to low-lying singlet excitations filling the
singlet-triplet gap in magnetic excitation spectrum of the square kagome
lattice [J.Richter, O.Derzhko and J.Schnack, Phys. Rev. B 105, 144427 (2022)].
According to position of , the leading exchange interaction
parameter in nabokoite is estimated to be about 60K. ESR spectroscopy
provides indications that antiferromagnetic structure below is
non-collinear. These complex thermodynamic and resonant properties signal the
presence of two weakly coupled magnetic subsystems in nabokoite, namely
spin-liquid with large singlet-triplet gap and antiferromagnet represented by
decorating ions. Separate issue is the observation of antiferroelectric-type
behavior in at low temperatures, which tentatively reduces the
symmetry and partially lifts frustration of magnetic interactions of decorating
copper ions with buckled square kagome lattice.Comment: 13 pages, 13 figure
Chemical Design Rules for Non-Fullerene Acceptors in Organic Solar Cells
Efficiencies of organic solar cells have practically doubled since the
development of non-fullerene acceptors (NFAs). However, generic chemical design
rules for donor-NFA combinations are still needed. Such rules are proposed by
analyzing inhomogeneous electrostatic fields at the donor-acceptor interface.
It is shown that an acceptor-donor-acceptor molecular architecture, and
molecular alignment parallel to the interface, results in energy level bending
that destabilizes the charge transfer state, thus promoting its dissociation
into free charges. By analyzing a series of PCE10:NFA solar cells, with NFAs
including Y6, IEICO, and ITIC, as well as their halogenated derivatives, it is
suggested that the molecular quadrupole moment of ca 75 Debye A balances the
losses in the open circuit voltage and gains in charge generation efficiency
Analysis of alternative splicing of cassette exons at single-cell level using two fluorescent proteins
Alternative splicing plays a major role in increasing proteome complexity and regulating gene expression. Here, we developed a new fluorescent protein-based approach to quantitatively analyze the alternative splicing of a target cassette exon (skipping or inclusion), which results in an open-reading frame shift. A fragment of a gene of interest is cloned between red and green fluorescent protein (RFP and GFP)-encoding sequences in such a way that translation of the normally spliced full-length transcript results in expression of both RFP and GFP. In contrast, alternative exon skipping results in the synthesis of RFP only. Green and red fluorescence intensities can be used to estimate the proportions of normal and alternative transcripts in each cell. The new method was successfully tested for human PIG3 (p53-inducible gene 3) cassette exon 4. Expected pattern of alternative splicing of PIG3 minigene was observed, including previously characterized effects of UV light irradiation and specific mutations. Interestingly, we observed a broad distribution of normal to alternative transcript ratio in individual cells with at least two distinct populations with âź45% and >95% alternative transcript. We believe that this method is useful for fluorescence-based quantitative analysis of alternative splicing of target genes in a variety of biological models
Controllability on infinite-dimensional manifolds
Following the unified approach of A. Kriegl and P.W. Michor (1997) for a
treatment of global analysis on a class of locally convex spaces known as
convenient, we give a generalization of Rashevsky-Chow's theorem for control
systems in regular connected manifolds modelled on convenient
(infinite-dimensional) locally convex spaces which are not necessarily
normable.Comment: 19 pages, 1 figur
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
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