Geometrically nonlinear analysis of the Apollo aft heat shield Final report, 1 Apr. 1966 - 15 Dec. 1966

Structural analysis of Apollo aft heat shield under water impact loading condition

On the electrical properties of transparent electrodes

In this paper we present the electrical properties of the typical transparent electrodes (ITO, AZO, IZO, FTO, PEDOT:PSS, etc.) prepared by different methods such as: spray pyrolysis, sputtering, sol-gel, thermal oxidation, PLD, etc. The modifications of electrical properties of electrodes during the sun exposure of the devices may explain some of problems arising in the I-V characterization of third-generation solar cells. The electrical resistivity stability of transparent electrode thin films as a function of the temperature is analysed in detail

A Calibrated Time Domain Envelope Measurement System for the Behavioral Modeling of Power Amplifiers

This paper presents a set-up which enables the generation and the calibrated time domain measurements of complex envelopes of modulated signals at both ports of non linear microwave power amplifiers. The architecture of the characterization tool is given. Examples of error corrected time domain envelopes at the input / output RF ports of a 36 dBm output power – 30dB power gain L-band SSPA are shown. Futhermore, the use of this characterization tool and a suitable processing of measurement data are applied to a novel measurement based behavioral modeling approach of non linear devices accounting for memory effects

Quantum Heating of a nonlinear resonator probed by a superconducting qubit

We measure the quantum fluctuations of a pumped nonlinear resonator, using a superconducting artificial atom as an in-situ probe. The qubit excitation spectrum gives access to the frequency and temperature of the intracavity field fluctuations. These are found to be in agreement with theoretical predictions; in particular we experimentally observe the phenomenon of quantum heating

Distribution of Kingella kingae Capsular Serotypes in France Assessed by a Multiplex PCR Assay on Osteoarticular Samples

International audienceno abstrac

3D Porous Architecture of Stacks of β-TCP Granules Compared with That of Trabecular Bone: A microCT, Vector Analysis, and Compression Study

The 3D arrangement of porous granular biomaterials usable to fill bone defects has received little study. Granular biomaterials occupy 3D space when packed together in a manner that creates a porosity suitable for the invasion of vascular and bone cells. Granules of beta-tricalcium phosphate (β-TCP) were prepared with either 12.5 or 25 g of β-TCP powder in the same volume of slurry. When the granules were placed in a test tube, this produced 3D stacks with a high (HP) or low porosity (LP), respectively. Stacks of granules mimic the filling of a bone defect by a surgeon. The aim of this study was to compare the porosity of stacks of β-TCP granules with that of cores of trabecular bone. Biomechanical compression tests were done on the granules stacks. Bone cylinders were prepared from calf tibia plateau, constituted high-density (HD) blocks. Low-density (LD) blocks were harvested from aged cadaver tibias. Microcomputed tomography was used on the β-TCP granule stacks and the trabecular bone cores to determine porosity and specific surface. A vector-projection algorithm was used to image porosity employing a frontal plane image, which was constructed line by line from all images of a microCT stack. Stacks of HP granules had porosity (75.3 ± 0.4%) and fractal lacunarity (0.043 ± 0.007) intermediate between that of HD (respectively 69.1 ± 6.4%, p < 0.05 and 0.087 ± 0.045, p < 0.05) and LD bones (respectively 88.8 ± 1.57% and 0.037 ± 0.014), but exhibited a higher surface density (5.56 ± 0.11 mm(2)/mm(3) vs. 2.06 ± 0.26 for LD, p < 0.05). LP granular arrangements created large pores coexisting with dense areas of material. Frontal plane analysis evidenced a more regular arrangement of β-TCP granules than bone trabecule. Stacks of HP granules represent a scaffold that resembles trabecular bone in its porous microarchitecture

Book Reviews

Reviews of the following books: Sir William Pepperrell of Colonial New England by Neil Rolde; New England and Foreign Relations 1789-1850 by Paul A. Varg; The Peace Reform in American History by Charles DeBenedetti

Synthesis of Hybrid Electroactive Materials by Low-Potential Electropolymerization of Gold Nanoparticles Capped with Tailored EDOT-Thiophene Precursor Units

The synthesis of gold nanoparticles (GNPs) capped with alkanethiols with terminal bithiophenic polymerizable groups, consisting of 3,4-ethylenedioxythiophene (EDOT) and 3-alkylsulfanylthiophene, is described. Transmission electron microscopy (TEM) and light diffusion show that these stabilized GNPs have an average size of 2–3 nm with low polydispersity. The electrochemical behavior of C10S-Au is investigated in dichloromethane in the presence of Bu4NPF6. The results show that these capped GNPs undergo straightforward and efficient electropolymerization under potentiodynamic or potentiostatic conditions. TEM images show that the electrodeposited films of the composite material present a very homogeneous structure, in which the size of the GNPs incorporated into the polythiophene matrix is unchanged. Results of cyclic voltammetry and spectroelectrochemistry obtained on polymer films deposited on platinum electrodes and transparent indium tin oxide electrodes, respectively, show that the reversible charging–discharging process and electrochromic behavior typical of poly(thiophenes) are preserved in the hybrid electroactive material