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fyysinen kuvaus: Suorakaiteinen pahvirasia, jossa on päälle painettava kansi. Pohjan ja kannen reunus on hieman ulkoneva. Reunukset ovat kullanväriset. Kansiosan pohja on vaaleansininen ja päälle on kuvattuna vihreällä lehtipuun oksalla lauleleva keltainen lintu, jota on kuuntelemassa kolme harmaata, eri värisiin vaatteisiin pukeutunutta kissaa. Vaatteissa on väreinä sinistä ja punaista.
Abstract Multiple strong impacts of anion doping Λ (Λ = oxygen vacancy, nitrogen, or hydrogen) on the optical properties in the near-infrared to vacuum ultraviolet spectral range are experimentally revealed in cube-on-cube-type epitaxial perovskite BaTiO3−δΛδ films (δ ≤ 0.01) grown on (001)SrTiO3 substrates. Compared to the reference undoped films and bulk crystal, the anion-doped films exhibit massive changes of the index of refraction in the transparency range Δn of ∼0.1 to 0.2, a profound bandgap widening ΔEg of ∼0.3 eV to 0.4 eV, a dopant-specific near-edge absorption, and doping-induced interband transitions. Both the conduction-band uplift and the changes in the index of refraction are ascribed to the internal stress and electric field, which result from epitaxially controlled dopant locations in the [Ba–O](001) planes. The dopant-induced in-gap states are responsible for the near-edge absorption, whereas the dopant-induced conduction-band states are suggested to modify the interband transitions and the intrinsic elasto- and electro-optic coefficients.
Electromagnetic waves propagation in the complex cavity with anisotropic hyperbolic metamaterial are investigated using direct calculation of modal field and dispersion equation. The transfer matrix method was adopted for arbitrary orientation of optical axis according to slab boundary. Increasing of the density of states in the cavity have show.
THz wave emission in the cavity which contains the graphene-multilayer asymmetric hyperbolic metamaterials is investigated numerically using transfer matrix method. In was assumed that the gain saturation appears as the decrease of imaginary part of effective dielectric permittivity. Gain -loss balance predicts the intensity of THz lasing.
Abstract Misfit strains arising from a film–substrate mismatch can induce novel phases and properties in the epitaxial films of perovskite oxides. Here we employ yet another effect, namely, strain-assisted formation of oxygen vacancies. We demonstrate the misfit-promoted presence of oxygen vacancies and related substitutional incorporation of anion dopants in the epitaxial films of archetypal perovskite oxide SrTiO3. Both the oxygen vacancies and hydrogen or nitrogen dopants are introduced in situ during the pulsed-laser deposition of the films using compressive substrates. The films exhibit peculiar chemical expansion and optical properties, which are consistent with substitutional anion doping.
Abstract Background: Temporomandibular disorders (TMDs) include pain and dysfunction in masticatory muscles and temporomandibular joints (TMJs). Applied relaxation (AR) is a coping skill that may be applicable for treatment of TMD. Objectives: The aim of this randomised, controlled study was to evaluate the effectiveness of AR as compared to stabilisation splint (SS), for treatment of TMD during 12‐month follow‐up. Methods: The data were derived from 96 university students seeking treatment due to TMD symptoms at Finnish Student Health Service in Finland. The subjects were randomly divided into two treatment groups: SS (n = 41) and AR (n = 51) groups. Clinical TMD examinations (a modified version of DC/TMD, Axis I) were performed for both the groups at baseline and 3‐, 6‐ and 12‐month follow‐ups. Depressive and non‐specific physical symptoms (NSPS) were estimated with Axis II questionnaire (RDC/TMD), and a number of other pain sites were screened at baseline and 12‐month follow‐up. Data were analysed by means of chi‐square test for both groups on five variables, t test for VAS pain intensity and repeated measures ANOVA for palpation pain at follow‐up points. Statistical significance was set on P < .05. Results: Decrease in the number of painful masticatory muscles and TMJs and VAS on pain intensity did not differ between groups. During follow‐up, NSPS and number of body pain sites decreased significantly more in the AR than the SS group. The dropout was 56 patients. Conclusion: Neither of the treatments showed more benefit in decreasing local TMD pain. AR gave more benefit on psychological well‐being and general pain symptoms.
Abstract Solution-processed organic–inorganic hybrid perovskites have attracted attention as light-harvesting materials for solar cells and photonic applications. The present study focuses on cubic single crystals and microstructures of CH3NH3PbBr3 perovskite fabricated by a one-step solution-based self-assembly method. It is seen that, in addition to the nucleation from the precursor solution, crystallization occurs when the solution is supersaturated, followed by the formation of a small nucleus of CH3NH3PbBr3 that self-assembles into bigger hollow cubes. A three-dimensional (3D) fluorescence microscopy investigation of hollow cubes confirmed the formation of hollow plates on the bottom; then, the growth starts from the perimeter and propagates to the center of the cube. Furthermore, the growth in the (001) direction follows a layer-by-layer growth model to form a complete cube, confirmed by scanning electronic microscopy (SEM) observations. Two-dimensional (2D)–3D fluorescence microscopy and photoluminescence (PL) measurements confirm a peak emission at 535 nm. To get more insights into the structural and optical properties, density functional theory (DFT) simulations were conducted. The electronic and optical properties calculated by DFT are in agreement with the obtained experimental values. The density-of-state (DOS) calculations revealed that the valence band maximum (VBM) consists of states contributed by Br and Pb, which agrees with the X-ray photoelectron spectroscopy valence band (XPS VB) measurements.
Abstract It is essential to mitigate power amplifier (PA) nonlinear (NL) effects to achieve energy-efficient radio communications. To restore the transmit signal quality, digital pre-distortion (DPD) is widely used. Recently, fast convergence DPD (FC-DPD) which offers good PA linearization has been proposed for next-generation broadcasting systems. However, it suffers from complexity issues and this paper addresses that drawback and we propose a low-complex version to make it hardware-friendly. We achieve significant complexity reduction by simplifying the Jacobian computation needed in the FC-DPD algorithm. This scheme can be extended to any memory-less PA model or a measured PA fitted to a polynomial model. We have provided proof that the proposed technique has linear complexity and the simulation results indicate that the proposed scheme achieves performance close to the FC-DPD algorithm. This method can be applied to other transmission systems as well.
Shot-noise measurements are widely used for the characterization of nonequilibrium configurations in electronic conductors. The recently introduced quantum tomography approach was implemented for the studies of electronic wave functions of few-electron excitations created by periodic voltage pulses in phase-coherent ballistic conductors based on the high-quality GaAs two-dimensional electron gas. Still relying on the manifestation of Fermi correlations in noise, we focus on the simpler and more general approach beneficial for local measurements of energy distribution (ED) in electronic systems with arbitrary excitations with well-defined energies and random phases. Using biased diffusive metallic wire as a test bed, we demonstrate the power of this approach and extract the well-known double-step ED from the shot noise of a weakly coupled tunnel junction. Our experiment paves the way for local measurements of generic nonequilibrium configurations applicable to virtually any conductor.
Abstract The extremely altered topmost surface layer, known as the white layer, formed in a medium-carbon low-alloy steel as result of impacts by angular 10–12 mm granite particles during the slurry erosion process is comprehensively investigated. For this purpose, the characteristics, morphology, and formation mechanism of this white layer are described based on the microstructural observations using optical, scanning and transmission electron microscopies as well as nanoindentation hardness measurements and modelling of surface deformation. The white layer exhibits a nanocrystalline structure consisting of ultrafine grains with an average size of 200 nm. It has a nanohardness level of around 10.1 GPa, considerably higher than that of untempered martensitic bulk material (5.7 GPa) achieved by an induction hardening treatment. The results showed that during the high-speed slurry erosion process, solid particle impacts brought forth conditions of high strain, high strain rate, and multi-directional strain paths. This promoted formation of a cell-type structure at first and later, after increasing the number of impacts, development of subgrains following by subgrain rotation and eventually formation of a nanocrystalline structure with ultra-high hardness. The model confirmed that high strain conditions — much higher than required for the onset of plastic deformation — can be achieved on the surface resulting in severe microstructural and property changes during the slurry erosion test.
Polystyrene-block-poly(1,4-isoprene)-block-poly(dimethyl siloxane)-block-poly(tert-butyl methacrylate)-block-poly(2-vinyl pyridine), PS-b-PI-b-PDMS-b-PtBMA-b-P2VP, self-assembles in acetone into polymersomes with asymmetric (directional) PI-b-PDMS membranes. The polymersomes, in turn, self-assemble into superstructures. Analogically to supravesicular structures at a smaller length scale, we refer to them as suprapolymersome structures. Electron tomograms are shown to be invaluable in the structural assessment of such complex self-assemblies.
Abstract Localized dynamic pressure pulses in the magnetosheath, or jets, have been a popular topic for discussion in recent decades. Studies show that they can propagate through the magnetosheath and impact the magnetopause, possibly showing up as geoeffective elements at ground level. However, questions still remain on how geoeffective they can be. Previous studies have been limited to case studies during few days and with only a handful of events. In this study we have found 65 cases of impacting jets using observations from the Multiscale Magnetospheric mission during 2015–2017. We examine their geoeffectiveness using ground-based magnetometers (GMAGs). From our statistics we find that GMAGs observe responses as fluctuations in the geomagnetic field with amplitudes of 34 nT, frequencies of 1.9 mHz, and damping times of 370 s. Further, the parallel length and the maximum dynamic pressure of the jet dictate the amplitude of the observed GMAG response. Longer and higher pressure jets inducing larger amplitude responses in GMAG horizontal components. The median time required for the signal to be detected by GMAGs is 190 s. We also examine if jets can be harmful for human infrastructure and cannot exclude that such events could exist.
Abstract The high resolution infrared spectra of hydrogen sulfide, H2MS (M = 32,33,34,36) in the natural abundance (95.041% of H232S, 0.748% of H233S, 4.196% of H234S and 0.015% of H236S), were recorded with a Bruker IFS 125HR Fourier transform infrared spectrometer (Zürich prototype ZP2001) and analyzed in the ν2 fundamental band region (700–1800 cm−1). In the experimental spectra 1564, 1019, and 685 transitions were assigned to the ν2 bands of H232S, H234S and H233S (the maximum values of the quantum numbers are Jmax./Kamax. = 24/17, 20/14, 17/14). The subsequent weighted fits of experimentally assigned transitions were made with the Watson Hamiltonian and a set of parameters which reproduces the initial 333/249/216 infrared ro-vibrational energy values has been obtained from the assigned experimental line positions with the root mean square deviations of drms = 2.2 x 10−4 cm−1, 1.7 x 10−4 cm−1 and 1.5 x 10−4 cm−1 for the H232S, H234S and H233S isotopologues. Additionally, 703, 182 and 23 transitions with the values of quantum numbers Jmax./Kamax. = 18/14, 14/8 and 9/6 belonging to the 2v2 − v2 hot bands of H232S, H234S and H233S (for the first time for the hot bands of the H234S and H233S species) were assigned in the experimental spectra. Rotational parameters of the ground vibrational state of H236S were re-determined, and, for the first time, 103 transitions (Jmax. = 11, Kamax. = 8) of the ν2 band of H236S were assigned in the experimental spectra. An analysis of ro-vibrational line strengths of 61 experimental isolated unsaturated and not too weak lines of the ν2 band of H232S was made (Jmax. = 9, Kamax. = 8), and five effective dipole moment parameters were obtained from the fit which reproduce the initial experimental line intensities with the drms = 1.4%. An analogous analysis was performed for the H234S and H233S isotopologues. The half-widths analysis was made on the basis of the multi-spectrum fit with the Hartmann-Tran line profile, and self-pressure broadening coefficients were estimated for a few tens of lines for the three most abundant isotopologues.
Background: Tailgating (following a lead vehicle too closely) is a key contributor to crashes and injury. While vehicle technology has the potential to reduce the trauma resulting from tailgating, full market penetration of these technologies is some time away. In the meantime, efforts to improve road safety can focus on supporting safer driver behaviour by targeting motivations for this behaviour. Method: A mixed methods design was used to understand reasons why drivers tailgate and potential countermeasures to reduce this behaviour. Qualitative data from 247 drivers (males = 29 %; mean age = 39.86; SD = 14.39) were sought to understand circumstances when drivers are tailgated and when they report tailgating. In a second study, 736 drivers (males = 41 %; mean age = 37.69; SD = 14.27) responded to questions developed from the qualitative findings to quantify the frequency of tailgating and reasons behind it. The theory of planned behaviour (TPB) was applied to understand whether self-reported intention to tailgate could be predicted by attitudes, perceived social acceptance of the behaviour, perceived behavioural control, and past tailgating behaviour. Results: Tailgating was a common behaviour. All drivers in the first study had experienced being tailgated by other drivers, while 77% had tailgated other vehicles; albeit 55% reported this was rare. Tailgating was unintentional (due to dense traffic; or lack of knowledge of safe following distance recommendations) or intentional (due to pressure from other drivers, anger or to change others’ behaviour). Structural equation modelling showed that TPB constructs of attitude, social norms, perceived behavioural control and past tailgating behaviour predicted intention to tailgate, accounting for 66% of the variance. Conclusion: TPB is a useful framework for explaining tailgating behaviour, or at least the intention to tailgate, and to develop interventions. These could focus on education of the risks of tailgating, the recommended safe following distances as well as strategies to support drivers maintaining safe following distances across different speed zones.
Abstract A dynamic, first-principles process model for a steelmaking electric arc furnace has been developed. The model is an integrated part of an application designed for optimization during operation of the furnace. Special care has been taken to ensure that the non-linear model is robust and accurate enough for real-time optimization. The model is formulated in terms of state variables and ordinary differential equations and is adapted to process data using recursive parameter estimation. Compared to other models available in the literature, a focus of this model is to integrate auxiliary process data in order to best predict energy efficiency and heat transfer limitations in the furnace. Model predictions are in reasonable agreement with steel temperature and weight measurements. Simulations indicate that industrial deployment of Model Predictive Control applications derived from this process model can result in electrical energy consumption savings of 1–2%.
Abstract Chemisorption synthesis on the basis of the binuclear compound [Bi2{S2CN(C3H7)2}6] (I) and preparative isolation of the ion-polymeric heteronuclear gold(III)–bismuth(III) complex ([Au{S2CN(C3H7)2}2]3[Bi2Cl9])n (II) are carried out. Compounds I and II are characterized in comparison by IR spectroscopy and 13C CP-MAS NMR. According to the X-ray diffraction analysis data (CIF file CCDC no. 1407705), the cationic moiety of compound II exhibits an unusually complicated supramolecular structure including six isomeric noncentrosymmetric complex cations [Au{S2CN(C3H7)2}2]+ (hereinafter A—F) and two binuclear anions [Bi2Cl9]3− as conformers. The isomeric gold(III) cations perform various structural functions. Owing to pair secondary interactions Au⋅⋅⋅S, cations B, C, E, and F form centrosymmetric ([E⋅⋅⋅E], [F⋅⋅⋅F]) and noncentrosymmetric ([B⋅⋅⋅C]) binuclear aggregates [Au2{S2CN(C3H7)2}4]2+, whereas cations A and D are not involved in dimerization. The strongest secondary Au···S bonds are formed between the binuclear and mononuclear cations, resulting in the formation of supramolecular cation-cationic polymer chains of two types: (⋅⋅⋅A⋅⋅⋅[B⋅⋅⋅C]⋅⋅⋅A⋅⋅⋅[B⋅⋅⋅C]⋅⋅⋅)n and (D⋅⋅⋅[E⋅⋅⋅E]⋅⋅⋅D⋅⋅⋅[F⋅⋅⋅F]⋅⋅⋅])n. In both chains, the gold atoms of the binuclear cations are characterized by a distorted octahedral coordination [S6], whereas in the mononuclear cations the gold atoms retain the square environment [S4]. The cation-anionic interactions are provided by secondary bonds Cl⋅⋅⋅S involving the terminal chlorine atoms of isomeric [Bi2Cl9]3− and the sulfur atoms of the binuclear cations [Au2{S2CN(C3H7)2}4]2+. The character of the thermal behavior of compounds I and II is studied by simultaneous thermal analysis with the identification of intermediate and final products of the thermal transformations. The thermolysis of compound I at 193–320°C is accompanied by the formation of Bi2S3 with an impurity of reduced metallic bismuth particles. The final products of the thermal transformations of compound II are reduced elemental gold and Bi2O3, and the thermal transformation intermediates are BiCl3 and Bi2S3.
Abstract As an environmentally friendly, low-cost and widely used polymer, poly(vinyl acetate) (PVAc) is worth modifying to achieve better properties. Here, we report on the influence of borate additives on the structure and properties of partially hydrolysed PVAc. In addition to the general crosslinking function of borate additives, an extraordinary plasticizing effect was found. By controlling the pH from 4 to 11 during sample preparation, the plasticizing and crosslinking effects can be shifted. In alkaline conditions, the degree of crosslinking in the PVAc/borate sample is increased; however, this increase declines gradually with an increase in the borate additive content, which impacts the morphology of the PVAc latex particles, as well as the mechanical and thermal properties of the PVAc/borate films. In contrast, in acidic conditions, the PVAc/borate films are plasticized by borate additives; thus, their ultimate mechanical strength, elastic moduli and thermal stabilities decrease, while the water diffusivities increase.
Abstract Industry 4.0—also known as the modern industrial revolution—nurtures close collaboration between various organizations so that they can come together for innovation. While aiming for digital transformation through such innovation, these organizations form certain interdependencies due to the pool of resources and tasks they agree to share to reach both common and independent goals. To understand those interdependencies, we studied a national innovation project in Finland called “Reboot IoT Factory,” which leveraged several resources, processes, and practices to successfully combine modern technologies in manufacturing in a competitive and sustainable way. The participants included in the project were factories, research organizations, and small and medium enterprises (SMEs). An actor dependency model was used to analyze the observed interdependencies through survey and interview data. The results showed strong goal, task, and resource dependencies between the participants. A conventional understanding of advantages and opportunities, such as increased experience sharing and possible long-term synergies, is elaborated; moreover, an analysis of the disadvantages and risks caused by interdependencies, such as delays in tasks and possible inefficiency through unnecessary complexity, is also conducted.
The lifetime of antiskyrmions at room temperature in an Mn-Pt-Sn tetragonal Heusler material has been calculated using an atomic scale representation including nearly a million spins. The evaluation of the pre-exponential factor in the Arrhenius rate expression for this large system is made possible by implementation of harmonic transition state theory that avoids evaluation of the eigenvalues of the Hessian matrix. The parameter values in the extended Heisenberg Hamiltonian, including anisotropic Dzyaloshinskii-Moriya interaction, are chosen to reproduce experimental observations [Nayak et al., Nature (London) 548, 561 (2017)10.1038/nature23466], in particular, the 150-nm diameter. The calculated results are consistent with the long lifetime observed in the laboratory and this exceptional stability of the antiskyrmions is found to result from large activation energy for collapse due to strong exchange coupling while the pre-exponential factor in the Arrhenius expression for the lifetime is found to have a typical magnitude of 10-12 s, despite the large number of spins. The long lifetime is, therefore, found to result from energetic effects rather than entropic effects in this system.
sisällön kuvaus: Ohjelma: Soittoa, H.T.Y. Soittokunta Runonlausuntoa, Martta Salmela Pilalauluja, Maailman lasten koori Pilapainia, Joutsenniemi Runonlausuntoa, Vilho Mantere Kilpailuja: Ampumisessa, Naulanlyönnissä. Rengaspöytä, Tanssia lavalla, Piirileikkiä Jättiläis-Ilotulitus alkaa klo 10 illalla. Ohjelmassa on 18 numeroita.
sisällön kuvaus: Huom.! Viimeinen tänä syksynä Sunnuntaina 21 p. syysk. Ohjelma: Soittoa, H:gin Työv.yhd. soittokunta Tervehdyspuhe, E. Nurmi Runo, neiti Edith Toivonen Puhe, pastori J. Uoti Runonlausuntoa, näyttelijä R. Länsivuori Pilalaulua, hra Nyström Sadunkerrontakilpailu Pilapainia ja voimistelua Ilveilyä, Tykkä ja kumpp. Kuplettilaulua, herra J. Auvinen Väliajoilla ja lopussa tanssia Heipparallaa, Puukkopöytä, Hyvä ravintola Viimeinen hauska tilaisuus!