A three-dimensional model describing stress-induced solid phase transformation with permanent inelasticity

The employment of shape memory alloys (SMA) in a large number of applications in the fields of aeronautical, biomedical, and structural engineering has been the motivation for an increasing interest in the direction of a correct and exhaustive modeling of their macroscopic behaviour.     

Synthesis of macrocyclic-acyclic polyether-ester compounds with isoxazole units

A series of macrocyclic-acyclic ether-ester compounds containing the isoxazole ring has been prepared by treating various dihydroxy compounds with 3,5-isoxazoledicarbonyl chloride.     

Synthesis of 3,3′ -methylenediisoxazoles

The synthesis of new 3,3′-methylenediisoxazoles (III), from 1,3-dichloromalondioxime (IX) and acetylenic compounds is reported. We have studied the transformation of the chloronitroso compound (VII), obtained from malondioxime (V) in ether with gaseous chlorine at ?70°, into IX. It was found that this was possible only by heating a DIYISO solution. The characteristics of the compounds which are described are reported.     

Impact of leg bending in the patient-specific computational fluid dynamics of popliteal stenting

Acta Mechanica Sinica - Endovascular treatment of the femoro-popliteal artery has recently become a valuable therapeutic option for popliteal arterial aneurysms. However, its efficacy remains...     

Chemistry of the amino radical ions,a new chain process of the protonated N-chloramines

δ-Deprotonation of amino radical cation occurs competitively with intramolecular hydrogen abstraction or aromatic amination depending on the acidity of the medium.     

Thin CdTe detectors mounted in back-to-back configuration: spectroscopic performance for low-energy X- and gamma-rays

Thin CdTe detectors (3×5 mm² electrode area and 0.5 mm thick) mounted in a back-to-back configuration with a common anode, have been characterized. The goal was to determine the dimensions of the detector region offering good spectroscopic performance. The detector size was chosen on the basis of previous studies performed on various detectors which have shown that the width of this “best spectroscopy region” assumes a constant value of about 0.4 mm in the device thickness range 1.0–2.5 mm, while it is largely reduced when using a smaller electrode area (2×2 mm²) and 0.5 mm thick devices. The tests were performed by irradiating the detectors with a well collimated E_X=122 keV photon beam. The results show that the edge effects observed in smaller detectors with the same configurations are significantly reduced, giving a better energy resolution, but not a wider region with good spectroscopic performance; at lower energies the effects of larger electrodes (increased electric capacitance and leakage current) result in a higher noise and an increased detection threshold.     

The dimensional reduction modelling approach for 3D beams: Differential equations and finite-element solutions based on Hellinger–Reissner principle

This paper illustrates an application of the so-called dimensional reduction modelling approach to obtain a mixed, 3D, linear, elastic beam-model.We start from the 3D linear elastic problem, formulated through the Hellinger–Reissner functional, then we introduce a cross-section piecewise-polynomial approximation, and finally we integrate within the cross section, obtaining a beam model that satisfies the cross-section equilibrium and could be applied to inhomogeneous bodies with also a non trivial geometries (such as L-shape cross section). Moreover the beam model can predict the local effects of both boundary displacement constraints and non homogeneous or concentrated boundary load distributions, usually not accurately captured by most of the popular beam models.We modify the beam-model formulation in order to satisfy the axial compatibility (and without violating equilibrium within the cross section), then we introduce axis piecewise-polynomial approximation, and finally we integrate along the beam axis, obtaining a beam finite element. Also the beam finite elements have the capability to describe local effects of constraints and loads. Moreover, the proposed beam finite element describes the stress distribution inside the cross section with high accuracy.In addition to the simplicity of the derivation procedure and the very satisfying numerical performances, both the beam model and the beam finite element can be refined arbitrarily, allowing to adapt the model accuracy to specific needs of practitioners.     

Methylation of 4-phenyl-1,2,3-thiadiazole. Reaction of nucleophiles with N-methyl-1,2,3-thiadiazolium salts and the crystal structure of the products

The methylation of 4-phenyl-1,2,3-thiadiazole yields both N-methylated products. These react differently with nucleophiles. The structure of the product of the reaction with morpholine has been determined through X-ray diffraction analysis.