Nucleation of Al3Zr and Al3Sc in aluminum alloys: from kinetic Monte Carlo simulations to classical theory

Zr and Sc precipitate in aluminum alloys to form the compounds Al3Zr and Al3Sc which for low supersaturations of the solid solution have the L12 structure. The aim of the present study is to model at an atomic scale this kinetics of precipitation and to build a mesoscopic model based on classical nucleation theory so as to extend the field of supersaturations and annealing times that can be simulated. We use some ab-initio calculations and experimental data to fit an Ising model describing thermodynamics of the Al-Zr and Al-Sc systems. Kinetic behavior is described by means of an atom-vacancy exchange mechanism. This allows us to simulate with a kinetic Monte Carlo algorithm kinetics of precipitation of Al3Zr and Al3Sc. These kinetics are then used to test the classical nucleation theory. In this purpose, we deduce from our atomic model an isotropic interface free energy which is consistent with the one deduced from experimental kinetics and a nucleation free energy. We test di erent mean-field approximations (Bragg-Williams approximation as well as Cluster Variation Method) for these parameters. The classical nucleation theory is coherent with the kinetic Monte Carlo simulations only when CVM is used: it manages to reproduce the cluster size distribution in the metastable solid solution and its evolution as well as the steady-state nucleation rate. We also find that the capillary approximation used in the classical nucleation theory works surprisingly well when compared to a direct calculation of the free energy of formation for small L12 clusters.Comment: submitted to Physical Review B (2004

Measurement of the Lambda^0_b lifetime in the decay Lambda^0_b -> J/psi Lambda^0 with the D0 Detector

We present measurements of the Lambda^0_b lifetime in the exclusive decay channel Lambda^0_{b}->J/psi Lambda^0, with J/psi to mu+ mu- and Lambda^0 to p pi-, the B^0 lifetime in the decay B^0 -> J/psi K^0_S with J/psi to mu+ mu- and K^0_S to pi+ pi-, and the ratio of these lifetimes. The analysis is based on approximately 250 pb^{-1} of data recorded with the D0 detector in pp(bar) collisions at sqrt{s}=1.96 TeV. The Lambda^0_b lifetime is determined to be tau(Lambda^0_b) = 1.22 +0.22/-0.18 (stat) +/- 0.04 (syst) ps, the B^0 lifetime tau(B^0) = 1.40 +0.11/-0.10 (stat) +/- 0.03 (syst) ps, and the ratio tau(Lambda^0_b)/tau(B^0) = 0.87 +0.17/-0.14 (stat) +/- 0.03 (syst). In contrast with previous measurements using semileptonic decays, this is the first determination of the Lambda^0_b lifetime based on a fully reconstructed decay channel.Comment: 7 pages, 4 figures, Submitted to Physical Review Letters, v2: Added FNAL Pub-numbe

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Anacephalaeoses id est Summa capita actorum Regum Lusitaniae

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El sacerdote santificado en la administracion del sacramento de la penitencia : cartas sobre el modo practico de administrar el santo sacramento... : obra utilisima a los confesores...

El autor es Charles Emmanuel Pallavicino (Aguilar, VI, 1330)Francisco Ordoqui es seudónimo de Julián de Fonseca (Palau, XVIII, p. 220)Sign.: a\p4\s, A-Z\p8\s, 2A-2D\p8\s, 2E\p6\

Статистические методы оценки кредитного риска

Results of credit risk of clients assessed by the most commonly statistical predictive in the banking system and their comparison: Discriminant analyses, Neural network and binary logistic regression. The analysis was conducted using random educational data with the following characteristics - borrower’s age, level ofeducation, number of years with current employer, number of years at the current address, household income inthousands, debt to income ration, credit card debt and other debts in thousand. The results of the analysis showthat the "neural networks" method is more reliable than others.В статье представлены результаты оценки кредитного риска в банковской системе и проведено сравнение наиболее актуальных методов: нейронных сетей, дискриминантного анализа и логистической регрессии. При оценке использовалась обучающая выборка, включающая следующие данные клиентов: возраст заемщика, уровень образования, продолжительность работы с нынешним работодателем, длительность проживания по текущему адресу, доход заемщика, отношение долга к доходу, долг по кредитной карте, другие долги. Результаты анализа показали, что метод нейронных сетей является более надежным по сравнению с остальными

Production Of 'Utazi' Flavoured Biscuit From Wheat and Cassava Flour Composite

Wheat flour, blended with cassava flour in a 1: 1 ratio were. used to produce three samples of biscuit. The biscuits were produced with 'Utazi' extract. Samples A had 1()% of the extract. Samples B and Chad 20 and 30% respectively. Proximate analyses of the samples showed that B had the highest moisture content 5.09%), while sample C was least with 2.88%. The crude protein contents are 8.05 and 7.62% for samples A and C respectively: The average fat content of the three samples was 25%. The mean score for sensory evaluation in colour, texture, flavour, taste_ and general acceptability, are respectively 7.9, 7.5, 6.1, 7.2 and 7.3 for samples A. For sample B they were 6.2, 6.5, 5.1, 5.0 and 5.8 and samples C; 6.8, 6.6, 5.5, 4.4 and 5.3. Relatively, sample A was most acceptable

Emmanuelis Aluari e Societati Iesu De institutione grammatica libri tres : adiecto praeteritorum ac supinorum catalogo Italicè P. Horatij Tursellini simulque tractatu de nominum generibus

Sign. : A-Z, 2APort. con orla tip. y grab. xi

Aphorismi confessariorum ex doctorum sententiis collecti

Encabezamiento completado con Palau, XVIII, p. 180Sign.: [ ]\p2\s, A-Z\p12\s, 2A-2D\p12\s, 2E\p8\sPort. con viñeta xi