Amorphous system

Continued part 1, part 2 of ebook "Energy conservation in buildings - The achievement of 50% energy saving: An environmental challenge?" provides readers with contents including: parametric steady state solar pond analyses - a numerical approach; central solar heating plants with seasonal storage - a site specific feasibility study for 8 locations; developments in wave energy; a solar heating plant with seasonal storage; solar DHW system evaluation with F-chart;...

246p dongmelo 20-05-2024 6 2   Download

Ebook "Electron paramagnetic resonance (Volume 21)" highlights major developments in this area, with results being set into the context of earlier work and presented as a set of critical yet coherent overviews. The topics covered describe contrasting types of application, ranging from biological areas such as EPR studies of free-radical reactions in biology and medically-related systems, to experimental developments and applications involving EPR imaging, the use of very high fields, and time-resolved methods.

232p coduathanh1122 27-03-2024 2 1   Download

Ebook "Applications of EPR in radiation research" presented in eight themes: elementary radiation processes (in situ and low temperature radiolysis, quantum solids); solid state radiation chemistry (crystalline, amorphous and heterogeneous systems); biochemistry, biophysics and biology applications (radicals in biomaterials, spin trapping, free-radical-induced DNA damage); materials science (polymeric and electronic materials, materials for treatment of nuclear waste, irradiated food);...

766p nhanphanguyet 28-01-2024 5 2   Download

This purpose of this work was to investigate the patient radiation doses and image quality of a Philips/Agfa computed radiographic (CR) system and a Philips indirect-capture digital radiographic (DR) system in a paediatric setting. A CDRAD digital radiographic contrast-detail phantom was used to assess radiographic image quality. Perspex slabs of three different thicknesses (6, 11 and 16 cm) were used to simulate paediatric patients of three arbitrary ages.

159p runthenight05 01-03-2023 3 2   Download

In particular, the system undergoes three stages. At first stage the relaxation proceeds slowly so that the energy of system slightly decreases and the samples structure remains amorphous. Within second stage a structural transformation occurs which significantly changes PRDF and DCN for the relatively short time. The energy of the system is dropped considerably and the amorphous structure transforms into the crystalline. Finally, the crystalline sample undergoes the slow relaxation which reduces the energy of system and eliminates structural defects in crystal lattices.

17p runordie3 27-06-2022 18 3   Download

This work presents the effect of pressure on the local microstructure of amorphous Germania (GeO2). The Molecular Dynamics simulation was performed on systems at 900 K and high pressure up to 70 GPa. The structural properties have been analyzed through the pair correlation function, coordination number distribution, and structure factors.

7p meyerowitz 25-12-2021 20 0   Download

Oganov potentials and period boundary condition to perform molecular dynamics simulation of amorphous and liquid Mg2SiO4 systems under pressures 0 GPa and 40 GPa. We clarify structure of amorphous Mg2SiO4 at 0 and 40 GPa and compared with the one of Mg2SiO4 at liquid state. Especially, the origin of sub-peaks in radial distribution function of O-O, Si-Si and Mg-Mg pairs is explained clearly. The change of radial distribution functions, coordination number and the number of all types of bonds including the corner-, edge- and face-sharing bonds is also discussed in detail in this paper.

9p nguaconbaynhay11 07-04-2021 11 1   Download

In this paper we use a new method based on Einstein’s equation to calculate the diffusion coefficient of impurity atoms in the disorder systems. Simulation results show that the diffusion coefficient D obeys the Arrhenius law. The dependence of the diffusion coefficient D on temperature for regular disordered lattice is also examined and discussed.

7p larachdumlanat127 20-12-2020 10 1   Download

The calculation of particular cases of two levels and uniform distributions of site and transition energies shows the applicability of the constructed expressions not only for site disorder system, but also for mixed system with both site and transition disorders. The blocking effect is studied and also discussed.

9p tamynhan8 04-11-2020 7 1   Download

To improve the solubility and oral bioavailability of erlotinib, a poorly water-soluble anticancer drug, solid self-emulsifying drug delivery system (SEDDS) was developed using solid inert carriers such as dextran 40 and Aerosil® 200 (colloidal silica). The preliminary solubility of erlotinib in various oils, surfactants, and co-surfactants was determined. Labrafil M2125CS, Labrasol, and Transcutol HP were chosen as the oil, surfactant, and co-surfactant, respectively, for preparation of the SEDDS formulations. The ternary phase diagram was evaluated to show the self-emulsifying area.

8p caothientrangnguyen 09-05-2020 13 1   Download

Drug–polymer miscibility is one of the fundamental prerequisite for the successful design and development of amorphous solid dispersion formulation. The purpose of the present work is to provide an example of the theoretical estimation of drug–polymer miscibility and solubility on the basis of Flory– Huggins (F–H) theory and experimental validation of the phase diagram.

10p caothientrangnguyen 09-05-2020 10 0   Download

In this paper, we present the results of studying magnetic properties and magnetocaloric effect of Fe90-xPrxZr10 (x = 1, 2 and 3) rapidly quenched alloys. The alloy ribbons with thickness of about 15 µm were prepared by melt-spinning method on a single roller system. X-ray diffraction patterns of the ribbons manifest their almost amorphous structure. Thermomagnetization measurements show that the Curie temperature of the alloys can be controlled to be near room temperature by changing concentration of Pr (x).

7p abcxyz123_02 03-03-2020 20 1   Download

A solid polymer electrolyte system based on poly(vinyl alcohol) (PVA) and poly(3,4-Etylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) complexed with magnesium bromide (MgBr2) salt was prepared using solution cast technique. The ionic conductivity is observed to increase with increasing MgBr2 concentration. The maximum conductivity was found to be 9.89 • 106 S/cm for optimum polymer composite film (30 wt.% MgBr2) at room temperature. The increase in the conductivity is attributed to the increase in the number of ions as the salt concentration is increased.

7p trinhthamhodang1 16-11-2019 17 3   Download

BCS class III drugs suffer from a drawback of low permeability even though they have high aqueous solubility. The objective of current work was to screen the suitability of glyceryl monooleate (GMO)/Pluronic F127 cubic phase liquid crystals precursors for permeation enhancement and in turn the bioavailability of tenofovir disoproxil fumarate (TDF), a BCS class III drug. Spray-drying method was used for preparation of TDF loaded liquid crystal precursors (LCP) consisting of GMO/Pluronic F127 and lactose monohydrate with an ability to in situ transform into stable cubic phases upon hydration.

10p trinhthamhodang1 14-11-2019 13 0   Download

This paper reports on the synthesis and characterisation of Dy2 O3 -doped magnesium borate (MB) glasses containing different modifiers, lithium, calcium, and sodium oxides. Glasses composed of (70-z)B2 O3 -20Li2 O; CaO; Na2 O-10MgO-zDy2 O3 (where 0.05≤z≤0.7 mol%) were prepared using the melt-quenching method. X-ray diffraction (XRD) pattern of the as-quenched samples verified their amorphous character. Differential thermal analysis (DTA) confirmed excellent glass-forming ability and thermal stability in the range of 0.60-0.67 and 0.18- 0.82, respectively.

6p caygaocaolon1 13-11-2019 20 1   Download

Acicular BaTiO3 particles were developed using solution systems. The morphology of BaC2O4 0.5H2O was controlled to acicular shape. Its phase transition to BaTiO3 was realized by introducing Ti ions from the coprecipitated amorphous phase. Acicular BaTiO3 particles have an aspect ratio as high as 18 and the particle size can be controlled by varying the growth period of BaC2O4 · 0.5H2O which governs the size of BaC2O4 · 0.5H2O particles. Acicular particles of crystalline BaTiO3 can be used for ultra-thin multilayer ceramic capacitors. ...

128p contentnew 10-04-2012 157 43   Download