Search results for "T method"

A practical entry to β-aryl-β-alkyl amino alcohols: application to the synthesis of a potent BACE1 inhibitor

2012

The 1,2-addition of alkyl Grignard reagents to readily available N-tert-butanesulfinyl ketimines, bearing an α-silyloxy substituent, proceeds in high yields and excellent diastereocontrol. The utility of the present method was demonstrated by the synthesis, in enantiomerically pure form, of one recently disclosed β-secretase (BACE1) inhibitor.

Modeling the non-linear deformation of a short-flax-fiber-reinforced polymer composite by orientation averaging

2013

Abstract The growing usage of short-flax-fiber-reinforced polymer composites in such applications as automotive industry necessitates the prediction of their mechanical response up to and beyond the limit of elasticity. Due to the imperfect, mechanical interlocking-dominated adhesion of natural fibers to most polymers, both fiber debonding and matrix yielding contribute to the non-linear deformation. In the present study, the deformation under an active loading of a short misaligned fiber composite is modeled by the orientation averaging approach, employing an analytical description of the behavior of a unit cell (UC), the parameters of which are determined using a FEM analysis of UC respon…

Direct monitoring of spin state in dinuclear iron(II) coordination compounds

2001

So far there has been no direct method to determine the spin state of molecules in dinuclear iron(II) compounds. The molecular fractions of high-spin (HS) and low-spin (LS) species have been deduced from magnetic susceptibility and zero-field Mossbauer spectroscopy data irrespective of whether they belong to LS–LS, LS–HS and HS–HS pairs. However, the distinction of pairs becomes possible if Mossbauer measurements are carried out in an external magnetic field. The proposed method opens new possibilities in the study of spin crossover phenomena in dinuclear compounds.

Données expérimentales et modélisation d’adsorption des systèmes N2(g)/montmorillonite potassique de Camp-Berteau et N2(g)/hydrotalcite carbonatée

1999

Resume In this paper capacities of adsorption of nitrogen onto two clays at 77 K are compared and analyzed. One system is a montmorillonite of Camp-Berteau saturated by potassium cation and the second one is an hydrotalcite saturated by carbonate anion. Adsorbed amounts have been obtained using a volumetric technique. So it is shown that the smectite adsorbed more than the hydrotalcite at the same relative pressure of nitrogen. The modelling of experimental data by various theories of adsorption as de Brunauer, Emmett et Teller (BET) and t-method are used to calculate the specific surface and to have access to the porosity of these materials at 77 K. Then it is shown that the adsorption of …

Lower bound limit analysis by bem: Convex optimization problem and incremental approach

2013

Abstract The lower bound limit approach of the classical plasticity theory is rephrased using the Multidomain Symmetric Galerkin Boundary Element Method, under conditions of plane and initial strains, ideal plasticity and associated flow rule. The new formulation couples a multidomain procedure with nonlinear programming techniques and defines the self-equilibrium stress field by an equation involving all the substructures (bem-elements) of the discretized system. The analysis is performed in a canonical form as a convex optimization problem with quadratic constraints, in terms of discrete variables, and implemented using the Karnak.sGbem code coupled with the optimization toolbox by MatLab…

Palkkatyöstä yrittäjäksi : sosiaali- ja terveysalalla toimivien yrittäjien ajattelutavan muutoksista

2013

STRAIN ENERGY EVALUATION IN STRUCTURES HAVING ZONE-WISE PHYSICAL- MECHANICAL QUANTITIES

2013

Among the possible aims of structural analysis inside some engineering spheres it can be useful to know the strain energy stored in all or in a part of the structure caused by assigned external actions, like the boundary and domain quantities. This serves to evaluate globally whether an assigned portion of structure undergoes an excessive store of energy able to compromise the stability of all the structure. This evaluation can be carried out through boundary work obtained using appropriate boundary generalized quantities connected to the results of the analysis on the whole structure. The advantage consists in using a very restricted number of quantities which, because of the characteristi…

Strain energy evaluation in structures having zone-wise physical-mechanical quantities

2013

Advanced spatio-temporal point processes for the Sicily seismicity analysis

2018

Due to the complexity of the generator process of seismic events, we study under several aspects the interaction structure between earthquake events using recently developed spatio-temporal statistical techniques and models. Using these advanced statistical tools, we aim to characterise the global and local scale cluster behaviour of the Easter Sicily seismicity considering the catalogue data since 2006, when the Italian National Seismic Network was upgraded and earthquake location was sensibly improved. Firstly, we characterise the global complex spatiotemporal interaction structure with the space-time ETAS model where background seismicity is estimated non-parametrically, while triggered …

Sto lat metody projektów w Polsce

2017

The text presents the development of the project method in Polish education throughout the last century. The project method was introduced into Poland after regaining independence, and it was implemented during the inter-war period (1918-1939) in some schools, both in urban and rural environments. Nevertheless, the method was at that time treated as a pedagogical novelty and experiment, rather than a natural part of school life. After 1945, education, like other aspects of socio-political life, was influenced by the communist propaganda, and the project method, supporting autonomy, democracy and empowerment, was not promoted as a valuable educational approach. After 1989, when progressive t…