566 research outputs found

    Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third Edition - Comments and Statistics

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    The Catalogue, available at the Centre de Donn\'ees Stellaires de Strasbourg, consists of 13573 records concerning the results obtained from different methods for 7778 stars, reported in the literature. The following data are listed for each star: identifications, apparent magnitude, spectral type, apparent diameter in arcsec, absolute radius in solar units, method of determination, reference, remarks. Comments and statistics obtained from CADARS are given.Comment: A&A, in pres

    Income Distribution in a Monetary Economy: A Ricardo-Keynes Synthesis

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    The paper provides a novel theory of income distribution and achieves an integration of monetary and value theories along Ricardian lines, extended to a monetary production economy as understood by Keynes. In a monetary economy, capital is a fund that must be maintained. This idea is captured in the circuit of capital as first defined by Marx. We introduce the circuit of fixed capital; this circuit is closed when the present value of prospective returns from employing it is equal to its supply price. In a steady-growth equilibrium with nominal wages and interest rates given, the equation that closes the circuit of fixed capital can be solved for prices, implying a definitive income distribution. Accordingly, the imputation for fixed capital costs is equivalent to that of a money contract of equal length, which is the payment per period that will repay the cost of the fixed asset, together with interest. It follows that if capital assets remain in use for a period longer than is required to amortize them, their earnings beyond that period have an element of pure rent

    Surface phase transitions in one-dimensional channels arranged in a triangular cross-sectional structure: Theory and Monte Carlo simulations

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    Monte Carlo simulations and finite-size scaling analysis have been carried out to study the critical behavior in a submonolayer lattice-gas of interacting monomers adsorbed on one-dimensional channels arranged in a triangular cross-sectional structure. The model mimics a nanoporous environment, where each nanotube or unit cell is represented by a one-dimensional array. Two kinds of lateral interaction energies have been considered: 1)1) wLw_L, interaction energy between nearest-neighbor particles adsorbed along a single channel and 2)2) wTw_T, interaction energy between particles adsorbed across nearest-neighbor channels. For wL/wT=0w_L/w_T=0 and wT>0w_T > 0, successive planes are uncorrelated, the system is equivalent to the triangular lattice and the well-known (3×3)(\sqrt{3} \times \sqrt{3}) [(3×3)∗][(\sqrt{3} \times \sqrt{3})^*] ordered phase is found at low temperatures and a coverage, θ\theta, of 1/3 [2/3][2/3]. In the more general case (wL/wT≠0w_L/w_T \neq 0 and wT>0w_T > 0), a competition between interactions along a single channel and a transverse coupling between sites in neighboring channels allows to evolve to a three-dimensional adsorbed layer. Consequently, the (3×3)(\sqrt{3} \times \sqrt{3}) and (3×3)∗(\sqrt{3} \times \sqrt{3})^* structures "propagate" along the channels and new ordered phases appear in the adlayer. The Monte Carlo technique was combined with the recently reported Free Energy Minimization Criterion Approach (FEMCA), to predict the critical temperatures of the order-disorder transformation. The excellent qualitative agreement between simulated data and FEMCA results allow us to interpret the physical meaning of the mechanisms underlying the observed transitions.Comment: 24 pages, 6 figure

    Standard and inverse site percolation of straight rigid rods on triangular lattices: Isotropic and nematic deposition/removal

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    Numerical simulations and finite-size scaling analysis have been carried out to study standard and inverse percolation of straight rigid rods on triangular lattices. In the case of standard (inverse) percolation, the lattice is initially empty(occupied) and linear kk-mers (kk linear consecutive sites) are randomly and sequentially deposited on(removed from) the lattice, considering an isotropic and nematic scheme. The study is conducted by following the behavior of four critical concentrations with the size kk, determined for a wide range of kk : (i)(i)[(ii)(ii)] standard isotropic[nematic] percolation threshold θc,k\theta_{c,k}[ϑc,k\vartheta_{c,k}], and (iii)(iii)[(iv)(iv)] inverse isotropic[nematic] percolation threshold θc,ki\theta^i_{c,k}[ϑc,ki\vartheta^i_{c,k}]. The obtained results indicate that: (1)(1) θc,k\theta_{c,k}[θc,ki\theta^i_{c,k}] exhibits a non-monotonous dependence with kk. It decreases[increases], goes through a minimum[maximum] around k=11k = 11, then increases and asymptotically converges towards a definite value for large kk θc,k→∞=0.500(2)\theta_{c,k \rightarrow \infty}=0.500(2)[θc,k→∞i=0.500(1)\theta^i_{c,k \rightarrow \infty}=0.500(1)]; (2)(2) ϑc,k\vartheta_{c,k}[ϑc,ki\vartheta^i_{c,k}] rapidly increases[decreases] and asymptotically converges towards a definite value for infinitely long kk-mers ϑc,k→∞=0.5334(6)\vartheta_{c,k \rightarrow \infty}=0.5334(6)[ϑc,k→∞i=0.4666(6)\vartheta^i_{c,k \rightarrow \infty}=0.4666(6)]; (3)(3) for both models, the curves of standard and inverse percolation thresholds are symmetric with respect to θ=0.5\theta = 0.5. Thus, a complementary property is found θc,k+θc,ki=1\theta_{c,k} + \theta^i_{c,k} = 1 (and ϑc,k+ϑc,ki=1\vartheta_{c,k} + \vartheta^i_{c,k} = 1), which has not been observed in other regular lattices. This condition is analytically validated by using exact enumeration of configurations for small systems; and (4)(4) in all cases, the model presents percolation transition for the whole range of kk

    Critical behavior of repulsive linear kk-mers on triangular lattices

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    Monte Carlo (MC) simulations and finite-size scaling analysis have been carried out to study the critical behavior in a submonolayer two-dimensional gas of repulsive linear kk-mers on a triangular lattice at coverage k/(2k+1)k/(2k+1). A low-temperature ordered phase, characterized by a repetition of alternating files of adsorbed kk-mers separated by k+1k+1 adjacent empty sites, is separated from the disordered state by a order-disorder phase transition occurring at a finite critical temperature, TcT_c. The MC technique was combined with the recently reported Free Energy Minimization Criterion Approach (FEMCA), [F. Rom\'a et al., Phys. Rev. B, 68, 205407, (2003)], to predict the dependence of the critical temperature of the order-disorder transformation. The dependence on kk of the transition temperature, Tc(k)T_c(k), observed in MC is in qualitative agreement with FEMCA. In addition, an accurate determination of the critical exponents has been obtained for adsorbate sizes ranging between k=1k=1 and k=3k=3. For k>1k>1, the results reveal that the system does not belong to the universality class of the two-dimensional Potts model with q=3q=3 (k=1k=1, monomers). Based on symmetry concepts, we suggested that the behavior observed for k=1,2k=1, 2 and 3 could be generalized to include larger particle sizes (k≥2k \geq 2).Comment: 17 pages, 13 figure

    Ozone tertiary treatment for pharmaceuticals and personal care products removal from municipal wastewater

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    An ozone pilot plant was installed at a conventional WWTP to evaluate the removal rate of emerging contaminants, drugs, and fragrances, as tertiary treatment. The filtered secondary effluent flow rate ranged between 1.3÷1.9 m3/h with a retention time of 10÷30 minutes and the plant operated with an ozone dose of 2- 4 mgO3/l. The results evidenced a high removal rate of 80-100% for most of the organic targeted compounds: Amisulpride, Azithromycin, Carbamazepine, Diclofenac, Clarithromycin and Ofloxacin. Lower removal rates from 20% to 80%, were observed for some substances e.g. Gabapentin Lactam, Galaxolidone, Irbesartan, Lamotrigine, and Tonalide. Advanced Oxidation Process (AOP) treatment with O3/H2O2, (0.5–1.0–2 molH2O2/molO3) allowed improved results for almost all these latter. In addition, ozone determined up to 42% removal of the absorbance at 254 nm and 20% of COD, wastewater disinfection, a decrease of the GC-MS chromatographic area, and no acute toxicity effect nor estrogenic and mutagen effects have been detected

    Differential Diagnosis and Clinical Management of a Case of COVID-19 in a Patient With Stage III Lung Cancer Treated With Radio-chemotherapy and Durvalumab

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    none14nononeGuerini A.E.; Borghetti P.; Filippi A.R.; Bonu M.L.; Tomasini D.; Greco D.; Imbrescia J.; Volpi G.; Triggiani L.; Borghesi A.; Maroldi R.; Pasinetti N.; Buglione M.; Magrini S.M.Guerini, A. E.; Borghetti, P.; Filippi, A. R.; Bonu, M. L.; Tomasini, D.; Greco, D.; Imbrescia, J.; Volpi, G.; Triggiani, L.; Borghesi, A.; Maroldi, R.; Pasinetti, N.; Buglione, M.; Magrini, S. M

    New measurement of exotic decay of 225^{225}Ac by 14^{14}C emission

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    The branching ratio of 225^{225}Ac decay by emission of 14^{14}C was remeasured under improved experimental conditions by using a radioactive source produced at the ISOLDE mass-separator at CERN and a nuclear track detector technique. The result, B=λ14C/λα=(4.5±1.4)10−12\lambda_{^{14}\textrm{C}} / \lambda_{\alpha} = (4.5 \pm 1.4) 10^{-12}, is consistent with the anomalously high value obtained in the 1993 experiment thus confirming the importance of nuclear structure effects in this exotic decay

    Gas and dust in the inner disk of the Herbig Ae star MWC 758

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    In this Letter we investigate the origin of the near-infrared emission of the Herbig Ae star MWC 758 on sub-astronomical unit (AU) scales using spectrally dispersed low resolution (R=35) AMBER/VLTI interferometric observations both in the H (1.7μ1.7 \mum) and K (2.2μ2.2 \mum) bands. We find that the K band visibilities and closure phases are consistent with the presence of a dusty disk inner rim located at the dust evaporation distance (0.4 AU) while the bulk of the H band emission arises within 0.1 AU from the central star. Comparing the observational results with theoretical model predictions, we suggest that the H band emission is dominated by an hot gaseous accretion disk.Comment: Accepted for publication in A&
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