Flow supercritical synthesis of brucite and magnesian T-O, T-O-T phyllosilicates: an opportunity to tune the structure with the solvent composition

Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 497-503
Author(s):  
Marie Claverie ◽  
François Martin ◽  
Christel Careme ◽  
Christophe Le Roux ◽  
Pierre Micoud ◽  
...  
Keyword(s):  
Supercritical Water ◽  
Layered Structure ◽  
Direct Consequence ◽  
Layered Material ◽  
Solvent Composition ◽  
Ethanol Mixture ◽  
Tetrahedral Sheet ◽  
Supercritical Synthesis

ABSTRACTThis work presents the synthesis of minerals with a layered structure in supercritical water/ethanol mixtures to decrease the critical coordinates of the solvent regarding water. Depending on the water/ethanol ratio of the solvent, we obtained three different minerals adopting an octahedral brucitic sheet: (1) without a Si-tetrahedral sheet (O); (2) associated with one Si-tetrahedral sheet (T-O); or (3) intercalated between two Si-tetrahedral sheets (T-O-T). We have thus shown that ethanol in a supercritical water/ethanol mixture changes the solubility of silicon with a direct consequence on the formation of the tetrahedral silicon sheets and thus makes it possible to control the structure of the synthesized layered material.

scholarly journals Solvothermal Preparation of Spherical Bi2O3 Nanoparticles Uniformly Distributed on Ti3C2Tx for Enhanced Capacitive Performance

2021 ◽  
Author(s):  
Tao Li ◽  
Xuefeng Chang ◽  
Lifang Mei ◽  
Xiayun Shu ◽  
Jidong Ma ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Chemical Stability ◽  
Layered Structure ◽  
Layered Material ◽  
Two Dimensional ◽  
Capacitive Performance ◽  
Solvothermal Preparation

Ti3C2Tx is a promising new two-dimensional layered material for supercapacitors with good electrical conductivity and chemical stability. However, Ti3C2Tx has problems such as collapse of the layered structure and low...

scholarly journals Oxidation Behavior of Ferritic Steel T22 Exposed to Supercritical Water

2019 ◽  
Vol 38 (2019) ◽  
pp. 476-484 ◽  
Author(s):  
Zhongliang Zhu ◽  
Hasan Izhar Khan ◽  
Qi Cao ◽  
Naiqiang Zhang
Keyword(s):  
Iron Oxide ◽  
Supercritical Water ◽  
Layered Structure ◽  
Outer Layer ◽  
Ferritic Steel ◽  
Oxidation Behavior ◽  
Spinel Oxide ◽  
Initial Oxidation ◽  
Exposure Temperature ◽  
Oxidation Stage

AbstractThe oxidation tests of Ferritic Steel T22 exposed to supercritical water (SCW) at 540–620°C and 25 MPa was performed for up to 1000 h. The oxidation rate increased with increasing exposure temperature and time. Oxide films formed on T22 have a double-layered structure with an outer layer consisting of iron oxide and an inner layer consisting of spinel oxide. Numerous pores on the surface can be observed at the initial oxidation stage while they seemed to heal with increasing exposure time at 620°C. Cracks occurred along grain boundaries in the oxide scale when T22 exposed for 200 h at 620°C. The influence of time and temperature on the oxidation of Ferritic Steel T22 was discussed.

THE SIMULATION ASSESSMENT OF THE VENEERING LAYERS OF PROSTHETIC CROWNS IN CONCENTRATED CONTACT

Tribologia ◽  
2021 ◽  
Vol 293 (5) ◽  
pp. 39-50
Author(s):  
Wojciech Ryniewicz ◽  
Anna M. Ryniewicz ◽  
Łukasz Bojko ◽  
Konrad Mazur
Keyword(s):  
Shear Stress ◽  
Layered Structure ◽  
Layered Material ◽  
Strength Parameters ◽  
Metal Type ◽  
Cad Cam ◽  
Concentrated Loading ◽  
The Impact ◽  
External Loads ◽  
Distribution Of Stresses

The aim of the study is to simulate and analyse the distributions of stresses and resultant displacements during concentrated loading of the layered material compositions used in prosthetic crowns in order to assess their resistance and demonstrate the impact of strength parameters of the veneer and framework on the transfer of external loads. The research materials are samples replicating the layered structure of prosthetic crowns. The load-bearing layers were made using CAD/CAM technology, and the dedicated veneering layers were fired or polymerized on the frameworks and constituted the top structure for cooperation during occlusion. If the material of the veneering layer differs from the material building the framework, for example, in the ceramic-metal type, spreading of the resultant displacements to the framework and high values of shear stress at the border of the veneering layer and the framework may be unfavourable and cause the veneer layer to chip off. This distribution of stresses and displacements may have a much smaller impact on the ceramic veneering of a ceramic or glass-ceramic framework, as both layers are much more homogeneous in terms of material.

Synthesis and Characterization of Calcium Phosphate-AMP Layered Materials

2006 ◽  
Vol 317-318 ◽  
pp. 769-772
Author(s):  
Motoki Kaneno ◽  
Kiyoko Sakamoto ◽  
Shunro Yamaguchi ◽  
Katsuaki Suganuma
Keyword(s):  
Thermal Analysis ◽  
Cell Adhesion ◽  
Calcium Phosphate ◽  
Layered Structure ◽  
Layered Materials ◽  
Layered Material ◽  
Synthesis And Characterization ◽  
Spectroscopic Analyses ◽  
Hydrolysis Of

Calcium phosphate-AMP layered material was synthesized by the hydrolysis of α−TCP in the presence of AMP at pH=6.2. The resulting composite was a mixture of DCPD and calcium phosphate-AMP layered material. The composition and structures of the calcium phosphate-AMP layered material were estimated based on elemental analysis, thermal analysis, and spectroscopic analyses. About 30 wt% of the composite comprises AMP, which is oriented in alternately layered structure of AMP and calcium phosphate layers. Furthermore, the composite showed better cell adhesion than DCPD.

Electron Diffraction Analysis of Microtwin Structures in Regrown (III) Silicon

1982 ◽  
Vol 40 ◽  
pp. 460-461
Author(s):  
P. Ling ◽  
R. Gronsky ◽  
J. Washburn
Keyword(s):  
Electron Diffraction ◽  
Ion Implantation ◽  
Diffraction Analysis ◽  
Diffraction Pattern ◽  
Direct Consequence ◽  
The Other ◽  
Electron Diffraction Analysis ◽  
Defect Microstructures ◽  
Ion Implanted

The defect microstructures of Si arising from ion implantation and subsequent regrowth for a (111) substrate have been found to be dominated by microtwins. Figure 1(a) is a typical diffraction pattern of annealed ion-implanted (111) Si showing two groups of extra diffraction spots; one at positions (m, n integers), the other at adjacent positions between <000> and <220>. The object of the present paper is to show that these extra reflections are a direct consequence of the microtwins in the material.

In situ TEM Studies of agglomeration of sub-nanometer Ru layers in Ru/C multilayers

1992 ◽  
Vol 50 (1) ◽  
pp. 256-257
Author(s):  
Tai D. Nguyen ◽  
Ronald Gronsky ◽  
Jeffrey B. Kortright
Keyword(s):  
Layered Structure ◽  
Driving Force ◽  
High Energy ◽  
Superior Performance ◽  
In Situ Tem ◽  
Rayleigh Instability ◽  
Practical Applications ◽  
Transmission Electron ◽  
Diffraction Patterns

Nanometer period Ru/C multilayers are one of the prime candidates for normal incident reflecting mirrors at wavelengths < 10 nm. Superior performance, which requires uniform layers and smooth interfaces, and high stability of the layered structure under thermal loadings are some of the demands in practical applications. Previous studies however show that the Ru layers in the 2 nm period Ru/C multilayer agglomerate upon moderate annealing, and the layered structure is no longer retained. This agglomeration and crystallization of the Ru layers upon annealing to form almost spherical crystallites is a result of the reduction of surface or interfacial energy from die amorphous high energy non-equilibrium state of the as-prepared sample dirough diffusive arrangements of the atoms. Proposed models for mechanism of thin film agglomeration include one analogous to Rayleigh instability, and grain boundary grooving in polycrystalline films. These models however are not necessarily appropriate to explain for the agglomeration in the sub-nanometer amorphous Ru layers in Ru/C multilayers. The Ru-C phase diagram shows a wide miscible gap, which indicates the preference of phase separation between these two materials and provides an additional driving force for agglomeration. In this paper, we study the evolution of the microstructures and layered structure via in-situ Transmission Electron Microscopy (TEM), and attempt to determine the order of occurence of agglomeration and crystallization in the Ru layers by observing the diffraction patterns.

Audiology Service Models in a Family Physician Practice Setting

2010 ◽  
Vol 6 (1) ◽  
pp. 24-32 ◽  
Author(s):  
Sridhar Krishnamurti
Keyword(s):  
Pediatric Patients ◽  
Practice Patterns ◽  
Healthcare Delivery ◽  
Direct Consequence ◽  
Direct Access ◽  
Practice Setting ◽  
Pediatric Populations ◽  
Family Practice Physicians ◽  
Primary Focus ◽  
Balance Problems

This article illustrates the potential of placing audiology services in a family physician’s practice setting to increase referrals of geriatric and pediatric patients to audiologists. The primary focus of family practice physicians is the diagnosis/intervention of critical systemic disorders (e.g., cardiovascular disease, diabetes, cancer). Hence concurrent hearing/balance disorders are likely to be overshadowed in such patients. If audiologists get referrals from these physicians and have direct access to diagnose and manage concurrent hearing/balance problems in these patients, successful audiology practice patterns will emerge, and there will be increased visibility and profitability of audiological services. As a direct consequence, audiological services will move into the mainstream of healthcare delivery, and the profession of audiology will move further towards its goals of early detection and intervention for hearing and balance problems in geriatric and pediatric populations.

THE EFFECT OF GONADECTOMY ON THE RESPONSE OF THE PITUITARY I. C. S. H.-CONTENT TO STEROID SEX HORMONES

1960 ◽  
Vol XXXV (II) ◽  
pp. 245-252 ◽  
Author(s):  
G. P. van Rees ◽  
F. J. A. Paesi
Keyword(s):  
Sex Hormones ◽  
Sex Steroids ◽  
Low Dose ◽  
Testosterone Propionate ◽  
Preceding Paper ◽  
Direct Consequence ◽  
Two Factors ◽  
Reflex Stimulation ◽  
Steroid Sex Hormones ◽  
Stimulation Of

ABSTRACT In the experiments reported in this paper the hypothesis that the decrease in the pituitary I. C. S. H.-content, which occurs after administration of steroid sex hormones in gonadectomized animals, is counteracted by a reflex stimulation of the hypophysis initiated by the operation has been investigated. If treatment with a low dose of testosterone propionate (100 μg) was started immediately after castration, the resulting decrease in the pituitary I. C. S. H.-content became more marked if the reflex stimulation of the hypophysis had been prevented. If, however, two months were allowed to elapse before the beginning of treatment, the presence or absence of this reflex was no longer of importance for the effect of testosterone propionate on the pituitary I. C. S. H.-content. And yet, in this case too, the decrease in the pituitary I. C. S. H.-content by testosterone propionate was less than in intact animals (see preceding paper). Hence this decrease appears to be counteracted by two factors: one rapidly occurring and short lasting, resulting from a reflex elicited by gonadectomy; the other gradually increasing in potency and possibly a direct consequence of the continued absence of pituitary inhibiting sex steroids.

Scanning-tunneling spectroscopy on conjugated polymer films

2003 ◽  
Vol 771 ◽  
Author(s):  
M. Kemerink ◽  
S.F. Alvarado ◽  
P.M. Koenraad ◽  
R.A.J. Janssen ◽  
H.W.M. Salemink ◽  
...  
Keyword(s):  
Polymer Films ◽  
Conjugated Polymer ◽  
Three Dimensional ◽  
Field Enhancement ◽  
Direct Consequence ◽  
Scanning Tunneling Spectroscopy ◽  
Tunneling Spectroscopy ◽  
Band Alignment ◽  
Scanning Tunneling ◽  
Order Of Magnitude

AbstractScanning-tunneling spectroscopy experiments have been performed on conjugated polymer films and have been compared to a three-dimensional numerical model for charge injection and transport. It is found that field enhancement near the tip apex leads to significant changes in the injected current, which can amount to more than an order of magnitude, and can even change the polarity of the dominant charge carrier. As a direct consequence, the single-particle band gap and band alignment of the organic material can be directly obtained from tip height-voltage (z-V) curves, provided that the tip has a sufficiently sharp apex.

Sign in / Sign up

Export Citation Format

Share Document