Search results for "Note"
showing 10 items of 10709 documents
Emergent ultrafast phenomena in correlated oxides and heterostructures
2017
The possibility of investigating the dynamics of solids on timescales faster than the thermalization of the internal degrees of freedom has disclosed novel non-equilibrium phenomena that have no counterpart at equilibrium. Transition metal oxides (TMOs) provide an interesting playground in which the correlations among the charges in the metal $d$-orbitals give rise to a wealth of intriguing electronic and thermodynamic properties involving the spin, charge, lattice and orbital orders. Furthermore, the physical properties of TMOs can be engineered at the atomic level, thus providing the platform to investigate the transport phenomena on timescales of the order of the intrinsic decoherence ti…
Comparison of adsorption properties of commercial silica and rice husk ash (RHA) silica: A study by NIR spectroscopy
2021
Abstract Adsorption properties of Silica gel (commercial silica), rice husk ash (RHA) silica, and their hydrothermally treated products towards water molecules were studied in this work. RHA silica was prepared by heating rice husk to 650°C for 4 h after pretreatment with hydrochloric acid. Portions of the samples of silica were evacuated at 200℃ and then allowed to adsorb water molecules from the surrounding air at either 42 or 50% humidity. The near infrared spectra of these samples were measured at different time intervals during their adsorption of water molecules. The evolved near infrared spectra were analyzed using second derivative techniques. Adsorption properties of these samples …
Complex composite structures with integrated piezoelectric transducers
2016
International audience; Nowadays, in different industrial fields as transport or aerospace, a research effort is conducted to reduce the structural weight. One of the most promising solutions is the use of composite structures due to their high stiffness, their low mass density and their low damping factor. At the same time, there is an intensification of the operational dynamic environment and an increase of durability requirements. These different expectations seem to be contradictory. One solution to manage these points is to design and manufacture smart composite structures with a fully distributed set of integrated piezoelec-tric transducers. These structures are able to modify their m…
The effect of ash and compost on the content and bioaccumulation of selected heavy metals
2019
Abstract Therefore the carried out study aimed at determination of the effect of high-calcium brown coal ash and compost being produced from municipal sewage sludge on the content and bioaccumulation of heavy metals in potato tubers, wheat grains and rapeseeds during a three-year period. Rapeseeds contained most Cd whereas wheat rains less. Potato tubers, wheat grains and rapeseeds contained more Mn, Ni and Zn in the fertilization objects with municipal sewage sludge with or without coal ash and compared to those where calcium carbonate or coal ash had been introduced into the soil at a dose corresponding to 1.5 Mg CaO · ha–1 at the beginning of this study. Differences in the Mn, Ni and Zn …
Alkylsilyl compounds as enablers of atomic layer deposition: analysis of (Et3Si)3As through the GaAs process
2016
A new chemistry has been developed to deposit GaAs, the quintessential compound semiconductor. The ALD process is based on a dechlorosilylation reaction between GaCl3 and (Et3Si)3As. Characteristic ALD growth was demonstrated, indicating good applicability of the alkylsilyl arsenide precursor. ALD of GaAs produced uniform, amorphous and stoichiometric films with low impurity content. This was done with saturating growth rates and an easily controlled film thickness. Crystallization was achieved by annealing. Even though the growth rate strongly decreased with increasing deposition temperature, good quality film growth was demonstrated at 175 to 200 °C, indicating the presence of an ALD wind…
Progress in the Development of CdTe and CdZnTe Semiconductor Radiation Detectors for Astrophysical and Medical Applications
2009
Over the last decade, cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) wide band gap semiconductors have attracted increasing interest as X-ray and gamma ray detectors. Among the traditional high performance spectrometers based on silicon (Si) and germanium (Ge), CdTe and CdZnTe detectors show high detection efficiency and good room temperature performance and are well suited for the development of compact and reliable detection systems. In this paper, we review the current status of research in the development of CdTe and CdZnTe detectors by a comprehensive survey on the material properties, the device characteristics, the different techniques for improving the overall detector…
Computational modeling of molecularly imprinted polymers as a green approach to the development of novel analytical sorbents
2018
Abstract The development of novel molecularly imprinted polymers (MIP) sorbents for specific chemical compounds require a lot of tedious and time-consuming laboratory work. Significant quantities of solvents and reagents are consumed in the course of the verification of appropriate configurations of polymerization reagents. Implementation of molecular modeling in the MIP sorbent development process appears to provide a solution to this problem. Appropriate simulations and computations facilitate the determination of the nature of interaction between the reagents and thus the selection of the best configuration of chemicals for the preparation of the sorbent. The article presents literature …
Zakres informacyjny uproszczonego sprawozdania finansowego jednostki małej
2015
W związku z implementacją zapisów nowej dyrektywy rachunkowości celem artykułu jest prezentacja zmian wprowadzonych w nowelizacji ustawy o rachunkowości z dnia 23 września 2015 r. Autorka określa ich wpływ na zakres informacyjny uproszczonego sprawozdania finansowego jednostki małej. Do rozwiązania przedstawionego problemu badawczego wykorzystano metodę analizy treści regulacji prawnych (krajowych i międzynarodowych) oraz metody porównań i wnioskowania. Nowelizacja ustawy o rachunkowości, wprowadzona w życie 23 września 2015 r., w myśl implementacji dyrektywy 2013/34/UE, ma na celu poprawę warunków wykonywania działalności gospodarczej oraz zniesienie bądź zminimalizowanie barier hamujących…
Electrocatalytic properties of manganese and cobalt polyporphine films toward oxygen reduction reaction
2018
International audience; Novel member of polymetalloporphines, namely manganese polymetalloporphine of type I (pMnP-I) obtained by ion exchange from magnesium polyporphine of type I (pMgP-I) is reported for the first time and compared to its cobalt analogue (pCoP-I). Both polymer films have been obtained via two-step procedure: demetaladon of the pMgP-I electrode film via its exposure to trifluoroacetic acid solution, resulting in formation of the metal-free polyporphine of type I (pH(2)P-I) followed by electrochemically induced incorporation of Co or Mn ions from the acetonitrile solution of cobalt and manganese perchlorates. A further oxidative transformation of pCoP-I, polymer films has l…
Le mortier de tuileau en France de l’Antiquité à l’époque moderne : héritage ou réinvention permanente ?
2020
International audience; Le mortier de tuileau, parfois appelé « ciment romain » ou « béton romain », est un mortier de chaux additionné d’une part de fragments de terre cuite architecturale qui confère au matériau des propriétés hydrauliques. Pouvant prendre sous l’eau, le produit final présente une résistance mécanique et une imperméabilité remarquables. De l’Antiquité à l’époque moderne, il fut alors d’usage courant dans la construction de structures liées à l’eau, de certains sols, ou encore de murs aux fonctions architecturales particulières. Les recommandations formulées par Vitruve dans son traité d’architecture au sujet de l’élaboration de ces mortiers sont bien souvent évoquées par …