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Influence of aging on electrocaloric effect in Li+ doped BaTiO3 ceramics
No full textAging creates significant changes in the properties of the ferroelectric materials such as dielectric and piezoelectric properties. However, the influence of aging on the electrocaloric effect (ECE) has not yet been investigated. In this work, we investigate the effect of the aging on the ECE in acceptor (Li+) doped BaTiO3 ceramics. We observe that aging induced defect polarization (P-D) reduces the saturation polarization of the doped samples until T-c=115 degrees C. Above that temperature P-D loses its effectiveness and material behaves like a fresh sample. Suppression of polarization below T-C due to aging effect results in a sharper slope change in the temperature dependence of electrical polarization in aged samples which causes an increase in the electrocaloric temperature change of Li+ doped BaTiO3 ceramics up to 23% at T-C. Above a critical Li doping amount, both negative and positive electrocaloric effect are observed in the same sample. (C) 2019 Elsevier B.V. All rights reserved
Apollonius Representation and Complex Geometry of Entangled Qubit States
No full text32nd International Colloquium on Group Theoretical Methods in Physics (ICGTMP Group) -- JUL 09-13, 2018 -- Czech Tech Univ, Prague, CZECH REPUBLICWOS: 000537619600085A representation of one qubit state by points in complex plane is proposed, such that the computational basis corresponds to two fixed points at a finite distance in the plane. These points represent common symmetric states for the set of quantum states on Apollonius circles. It is shown that, the Shannon entropy of one qubit state depends on ratio of probabilities and is a constant along Apollonius circles. For two qubit state and for three qubit state in Apollonius representation, the concurrence for entanglement and the Cayley hyperdeterminant for tritanglement correspondingly, are constant on the circles as well. Similar results are obtained also for n- tangle hyperdeterminant with even number of qubit states. It turns out that, for arbitrary multiple qubit state in Apollonius representation, fidelity between symmetric qubit states is also constant on Apollonius circles. According to these, the Apollonius circles are interpreted as integral curves for entanglement characteristics. The bipolar and the Cassini representations for qubit state are introduced, and their relations with qubit coherent states are established. We proposed the differential geometry for qubit states in Apollonius representation, defined by the metric on a surface in conformal coordinates, as square of the concurrence. The surfaces of the concurrence, as surfaces of revolution in Euclidean and Minkowski spaces are constructed. It is shown that, curves on these surfaces with constant Gaussian curvature becomes Cassini curves
Mid-infrared spectroscopic detection of sunflower oil adulteration with safflower oil
No full textThe oil industry is in need of rapid analysis techniques to differentiate mixtures of safflower-sunflower oils from pure oils. The current adulteration detection methods are generally cumbersome and detection limits are questionable. The aim of this study was to test the capability of a mid-infrared spectroscopic method to detect the adulteration of sunflower oil with safflower oil compared to fatty acid analysis. Mid-infrared spectra of pure oils and their mixtures at the 10-60% range were obtained at 4000-650 cm(-1) wavenumber and fatty acid profiles were determined. Data were analyzed by multivariate statistical analysis techniques. The lowest level of detection was obtained with mid-infrared spectroscopy at 30% while the fatty acid profile could determine adulteration at around 60%. Adulteration levels were predicted successfully using PLS regression analysis of infrared data with R-2 (calibration) = 0.96 and R-2 (validation) = 0.93. As a rapid and minimum waste generating technique, mid-infrared spectroscopy could be a useful tool for the screening of raw material to detect safflower-sunflower oil mixtures
Search for pair production of second-generation leptoquarks at √s=13 TeV
No full textA search for pair production of second-generation leptoquarks is performed using proton-proton collision data collected at root s = 13 TeV in 2016 with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 35.9 fb(-1). Final states with two muons and two jets, or with one muon, two jets, and missing transverse momentum are considered. Second-generation scalar leptoquarks with masses less than 1530(1285) GeVare excluded for ss = 1.0(0.5), where ss is the branching fraction for the decay of a leptoquark to a charged lepton and a quark. The results of the search are also interpreted as limits on the pair production of long-lived top squarks in an R-parity violating supersymmetry model that has a final state with two muons and two jets. These limits represent the most stringent limits to date on these models
The frequency function and its connections to the Lebesgue points and the Hardy-Littlewood maximal function
No full textThe aim of this work is to extend the recent work of the author on the discrete frequency function to the more delicate continuous frequency function tau, and further to investigate its relations to the Hardy-Littlewood maximal function M, and to the Lebesgue points. We surmount the intricate issue of measurability of tau f by approaching it with a sequence of carefully constructed auxiliary functions for which measurability is easier to prove. After this, we give analogues of the recent results on the discrete frequency function. We then connect the points of discontinuity of Mf for f simple to the zeros of tau f, and to the non-Lebesgue points of f
Search for narrow Hγ resonances in proton-proton collisions at √s=13 TeV
No full textPubMed: 30932612A search for heavy, narrow resonances decaying to a Higgs boson and a photon (Hy) has been performed in proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb-1 collected with the CMS detector at the LHC in 2016. Events containing a photon and a Lorentz-boosted hadronically decaying Higgs boson reconstructed as a single, large-radius jet are considered, and the y jet invariant mass spectrum is analyzed for the presence of narrow resonances. To increase the sensitivity of the search, events are categorized depending on whether or not the large-radius jet can be identified as a result of the merging of two jets originating from b quarks. Results in both categories are found to agree with the predictions of the standard model. Upper limits on the production rate of Hy resonances are sct as a function of their mass in the range of 720-3250 GeV, representing thc most stringent constraints to date
Search for vector-like quarks in events with two oppositely charged leptons and jets in proton-proton collisions at √s = 13 TeV
No full textPubMed: 31180390A search for the pair production of heavy vector-like partners T and B of the top and bottom quarks has been performed by the CMS experiment at the CERN LHC using proton-proton collisions at . The data sample was collected in 2016 and corresponds to an integrated luminosity of 35.9 production include those where one of the T quarks decays via TtZ and the other via TbW, tZ, or tH, where H is a Higgs boson. For the BB case, final states include those where one of the B quarks decays via BbZ and the other BtW, bZ, or bH. Events with two oppositely charged electrons or muons, consistent with coming from the decay of a Z boson, and jets are investigated. The number of observed events is consistent with standard model background estimations. Lower limits at 95% confidence level are placed on the masses of the T and B quarks for a range of branching fractions. Assuming 100% branching fractions for TtZ, and BbZ, T and B quark mass values below 1280 and 1130 respectively, are excluded
Symmergent gravity, seesawic new physics, and their experimental signatures
No full textThe standard model of elementary particles (SM) suffers from various problems, such as power-law ultraviolet (UV) sensitivity, exclusion of general relativity (GR), and absence of a dark matter candidate. The LHC experiments, according to which the TeV domain appears to be empty of new particles, started sidelining TeV-scale SUSY and other known cures of the UV sensitivity. In search for a remedy, in this work, it is revealed that affine curvature can emerge in a way restoring gauge symmetries explicitly broken by the UV cutoff. This emergent curvature cures the UV sensitivity and incorporates GR as symmetry-restoring emergent gravity (symmergent gravity, in brief) if a new physics sector (NP) exists to generate the Planck scale and if SM+NP is Fermi-Bose balanced. This setup, carrying fingerprints of trans-Planckian SUSY, predicts that gravity is Einstein (no higher-curvature terms), cosmic/gamma rays can originate from heavy NP scalars, and the UV cutoff might take right value to suppress the cosmological constant (alleviating fine-tuning with SUSY). The NP does not have to couple to the SM. In fact, NP-SM coupling can take any value from zero to Lambda SM2/Lambda NP2 if the SM is not to jump from Lambda SM approximate to 500GeV to the NP scale Lambda NP. The zero coupling, certifying an undetectable NP, agrees with all the collider and dark matter bounds at present. The seesawic bound Lambda SM2/Lambda NP2, directly verifiable at colliders, implies that (i) dark matter must have a mass less than or similar to Lambda SM, (ii) Higgs-curvature coupling must be approximate to 1.3%, (iii) the SM RGEs must remain nearly as in the SM, and (iv) right-handed neutrinos must have a mass less than or similar to 1000TeV. These signatures serve as a concise testbed for symmergence
Search for nonresonant Higgs boson pair production in the b b ¯ b b ¯ final state at √s = 13 TeV
No full textResults of a search for nonresonant production of Higgs boson pairs, with each Higgs boson decaying to a b (b) over bar pair, are presented. This search uses data from proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), collected by the CMS detector at the LHC. No signal is observed, and a 95% confidence level upper limit of 847 fb is set on the cross section for standard model nonresonant Higgs boson pair production times the squared branching fraction of the Higgs boson decay to a b (b) over bar pair. The same signature is studied, and upper limits are set, in the context of models of physics beyond the standard model that predict modified couplings of the Higgs boson
Retrofitting of masonry structures considering the architectural perspective: A case study in Foca, Izmir
No full text3rd World Multidisciplinary Civil Engineering, Architecture, Urban Planning Symposium (WMCAUS); JUN 18-22, 2018; Prague, Czech RepublicMasonry structures have been preferred for centuries in most of the countries across the world because they are easy to build and economical due to the use of local materials in their construction. As a result of high usage volume, masonry structures that created the architectural section of history and culture constitute an important part of the current building stock despite the developing and diversified construction techniques nowadays. The protection of these structures, which are important both in terms of their cultural values and their transfer to future generations, is of great importance in the architectural point of view. For this purpose, a masonry structure from Foca is selected. The material properties and architectural plan of the structure are determined in accordance with the original one. The structure is modelled by using a software program under seismic effects. Displacement and stress values for each acceleration record are obtained. Besides, an evaluation is made in the direction of the analysis results and it is determined according to the seismic performance of the structure. After that, the structure is retrofitted according to the current design codes and without distorting the architectural perspective. This study aims to increase the structural strength of the case building by using conventional and modern techniques for the recovery of the structure