Mechanical and thermal characterization of a beet pulp-starch composite for building applications

This work shows the making of a new bio-based material for building insulation from sugar beet pulp and potato starch. The material is both lightweight and ecofriendly. The influence of starch/ sugar beet pulp ratio (S/BP) is studied. Four binder mass dosages are considered, 10, 20, 30 and 40% (relative to the beet pulp). Samples are characterized in terms of absolute and bulk density, compressive and flexural strength, as well as thermal properties (thermal conductivity and thermal inertia). The compressive strength increases linearly with the S/BP mass ratio to reach 0.52 MPa and the compressive strain is 30%. The thermal conductivity is to around 0.070 W/m. K. The results obtained shows that increasing starch amount tends to decrease composite porosity but increases thermal conductivity and mechanical properties. Depending on the starch content, beet pulp composites have a good thermal and can be used as building materials

The ThomX project status

Work supported by the French Agence Nationale de la recherche as part of the program EQUIPEX under reference ANR-10-EQPX-51, the Ile de France region, CNRS-IN2P3 and Université Paris Sud XI - http://accelconf.web.cern.ch/AccelConf/IPAC2014/papers/wepro052.pdfA collaboration of seven research institutes and an industry has been set up for the ThomX project, a compact Compton Backscattering Source (CBS) based in Orsay - France. After a period of study and definition of the machine performance, a full description of all the systems has been provided. The infrastructure work has been started and the main systems are in the call for tender phase. In this paper we will illustrate the definitive machine parameters and components characteristics. We will also update the results of the different technical and experimental activities on optical resonators, RF power supplies and on the electron gun

Mechanical and thermal characterization of a beet pulp-starch composite for building applications

International audienceThis work shows the making of a new bio-based material for building insulation from sugar beet pulp and potato starch. The material is both lightweight and ecofriendly. The influence of starch/ sugar beet pulp ratio (S/BP) is studied. Four binder mass dosages are considered, 10, 20, 30 and 40% (relative to the beet pulp). Samples are characterized in terms of absolute and bulk density, compressive and flexural strength, as well as thermal properties (thermal conductivity and thermal inertia). The compressive strength increases linearly with the S/BP mass ratio to reach 0.52 MPa and the compressive strain is 30%. The thermal conductivity is to around 0.070 W/m. K. The results obtained shows that increasing starch amount tends to decrease composite porosity but increases thermal conductivity and mechanical properties. Depending on the starch content, beet pulp composites have a good thermal and can be used as building materials

Characterization of beet-pulp fiber reinforced potato starch biopolymer composites for building applications

International audienceThis work deals with the making of a new renewable green material for building insulation from sugar beet pulp and potato starch. The material is both lightweight and ecofriendly. The influence of starch/extruded sugar beet pulp mass ratio (S/EBP) is studied. Four mass ratios are considered, 10, 20, 30 and 40% (relative to the starch). Samples are characterized in terms of absolute and bulk density, sound absorption coefficient, compressive and flexural strength, as well as and hygrothermal properties (the moisture buffering value and thermal conductivity). The sound absorption coefficient shows that this material is a good sound absorber, especially in medium and high frequencies. The sound absorption capacity depends on the fiber content and the humidity content. The best values are between 0.6 and 0.8. The compressive strength increases linearly with the S/EBP weight ratio to reach 0.52 MPa and the compressive strain is 30%. The elasticity modulus and the Poisson’s ratios were also studied. The transversal and vertical strain were measured using ARAMIS optical system. The moisture buffering value was measured according to Nordtest Protocol. The recorded moisture buffering value was between 2.6 and 2.8 g/(%RH.m2) and shows that the sugar beet pulp-starch composite is an excellent hygric regulator. The thermal conductivity is to around 0.070 W/(m·K). The results obtained shows that increasing starch amount tends to decrease composite porosity but increases thermal conductivity and mechanical properties. Depending on the starch content, beet pulp composites have a good thermal and acoustical performance and can be used as building materials

Effect of Scoria on Various Specific Aspects of Lightweight Concrete

Abstract Experimental research on the technical characteristics of lightweight concretes incorporating scoria was conducted. The objective of this research is to investigate the feasibility and effectiveness of the use of scoria, in lightweight concretes. Coarse scoria of 5/10 and 10/20 mm were used. A portion of the aggregate mixtures had an average particle size ≤100 μm. Scorias are often used as the constituents of structural concrete and insulating materials. The usability of the concretes tested in this study broadens as the porosity of the mixtures decreased and the cement dosage increased. According to the cement dosage and frequency types, the absorption coefficients of concretes ranged from 0.14 to 0.47. A compressive strength of 19 MPa corresponded to a density of 1800 kg/m3; compressive strengths from 10 to 18 MPa mapped to densities ranging from 1300 to 1700 kg/m3. The thermal conductivity of mixed concretes without scoria reached a maximum value of 0.268 W/m K. The thermal conductivity values of the concretes mixed without sand were below 0.403 W/m K. As sand content increased, the conductivity evolved from 0.565 to 0.657 W/m K. Freeze–thaw stability tests were conducted for 400 cycles or until specimens deteriorated. The experimental results helped in determining the optimum mixing conditions for the inclusion of scoria in cement to produce lightweight concretes

Photomagnetic nanorods of the Mo(CN)8Cu2 coordination network

Nanorods of the photomagnetic coordination network Mo(CN)8Cu2 coated with polyvinylpyrrolidone were prepared and exhibit an enhanced effect upon irradiation when compared to the bulk..

Photomagnetic nanorods of the Mo(CN)8Cu2 coordination network

Nanorods of the photomagnetic coordination network Mo(CN)8Cu2 coated with polyvinylpyrrolidone were prepared and exhibit an enhanced effect upon irradiation when compared to the bulk..

Mechanochromic luminescence and liquid crystallinity of molecular copper clusters

International audienceMolecular copper iodide clusters with the [Cu4I4] cubane core have been functionalized by phosphine ligands carrying protomesogenic gallate-based derivatives bearing either long alkyl chains (C8, C12, and C16) or cyanobiphenyl (CBP) fragments. The mesomorphic properties of the functionalized clusters were studied by combining differential scanning calorimetry (DSC), polarized optical microscopy (POM), and small-angle X-ray scattering (SAXS) experiments. Whereas clusters functionalized solely with long alkyl chains present amorphous or crystalline states, the cluster carrying CBP fragments displays liquid crystal properties with the formation of a smectic A mesophase from room temperature up to 100 °C. Temperature-dependent photoluminescence measurements show that the CBP derivative displays an unusual luminescence thermochromism which is possibly due to a resonance energy transfer mechanism between the emissive [Cu4I4] inorganic and CBP moieties. The emission properties of this original cluster are also sensitive to variation of local order of the molecular assembly. Moreover, the liquid crystalline properties imported on the inorganic core allow for a facile deformation of its local environment, leading to mechanochromic properties related to modulation of intramolecular interactions. Indeed, mechanical constraints on the molecularly self-assembled structure induce changes at the molecular level by modification of the [Cu4I4] inorganic cluster core geometry and in particular of the strength of the cuprophilic interactions

Near-Infrared Dual-Band LSPR Coupling in Oriented Assembly of Doped Metal Oxide Nanocrystal Platelets

International audienceCoupling effects of localized surface plasmon resonance (LSPR) represent an efficient means to tune the plasmonic modes and to enhance the near-field. While LSPR coupling in metal nanoparticles has been extensively explored, limited attention has been given to heavily doped semiconductor nanocrystals. Here, we investigate the LSPR coupling behavior of Cs-doped tungsten oxide (CsxWO3−δ) nanocrystal platelets as they undergo an oriented assembly into parallel stacks. The oriented assembly was achieved by lowering the dispersion stability of the colloidal nanoplatelets, of which the basal surface was selectively ligand-functionalized. This assembly induces simultaneous blue-shifts and red-shifts of dual-mode LSPR peaks without compromising the intensity and quality factor. This stands in contrast to the significant damping, broadening, and overall red-shift of the LSPR observed in random assemblies. Computational simulations successfully replicate the experimental observations, affirming the potential of this coupling phenomenon of near-infrared dual-mode LSPR in diverse applications including solar energy, bio-optics, imaging, and telecommunications