Novel Proton-Conducting Oxygen-Deficient Complex Oxides: Synthesis, Hydration Processes, Transport Properties

2020 ◽  
Vol 998 ◽  
pp. 209-214
Author(s):  
Nataliia Tarasova ◽  
Irina Animitsa ◽  
Anzhelika Galisheva
Keyword(s):  
Electrical Properties ◽  
Transport Properties ◽  
Cell Volume ◽  
Water Uptake ◽  
Complex Oxides ◽  
Complex Oxide ◽  
Niobium Doping ◽  
Proton Current ◽  
Order Of Magnitude ◽  
First Time

The complex oxide BaLaIn0.9Nb0.1O4.1 with Ruddlesden-Popper structure was obtained for the first time. It was found that the introduction of niobium into indium sublattice leads to the increase in the cell volume. Hydration processes and electrical properties have been investigated. For BaLaIn0.9Nb0.1O4.1 it was proved the capability for water uptake and the appearance of proton current carriers. It was established that niobium doping leads to the increase of conductivity compared to undoped composition BaLaInO4 at ~1 order of magnitude in whole temperature range.

Structural Conductivity of Carbon Nanotubes

2008 ◽  
Vol 59 (10) ◽  
pp. 1169-1171 ◽  
Author(s):  
Zoltan Borsos ◽  
Viorel-Puiu Paun ◽  
Irinel Casian Botez ◽  
Cristina-Maria Stoica ◽  
Petrica Vizureanu ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Fractal Dimension ◽  
Electrical Properties ◽  
Transport Properties ◽  
Structural Form ◽  
Structural Symmetry

In this paper, the explicit connection between the high structural symmetry of the carbon nanotubes and the electrical properties is studied. An interesting path effect on the transport properties will be proved. For a bidimensional lattice, the conductivity sx depends on the structural form, which determines the shape of electron path, respectively it is direct proportional to the fractal dimension of this path.

Detection and Quantification of 7-Hydroxydehydroepiandrosterone Epimers in Three Body Fluids

2002 ◽  
Vol 67 (1) ◽  
pp. 10-18 ◽  
Author(s):  
Richard Hampl ◽  
Martin Hill ◽  
Luboslav Stárka
Keyword(s):  
Healthy Subjects ◽  
Serum Levels ◽  
Body Fluids ◽  
Gas Chromatography Mass Spectrometry ◽  
Specific Radioimmunoassay ◽  
Order Of Magnitude ◽  
Three Body ◽  
First Time ◽  
Nanomolar Range ◽  
Detection And Quantification

3β,7α-Dihydroxyandrost-5-en-17-one (1) (7α-OH-DHEA) and its 7β-hydroxy epimer 2 (7β-OH-DHEA) - 7α- and 7β-hydroxydehydroepiandrosterone - were detected and quantified in three human body fluids: in blood serum, saliva and ejaculate. Specific radioimmunoassay and gas chromatography-mass spectrometry have been used. For the first time the data on changes of these dehydroepiandrosterone metabolites are reported for a representative group of healthy subjects of both sexes (172 females and 217 males) during the life span. The serum levels of both 7-hydroxydehydroepiandrosterone epimers in serum and also in semen were in the low nanomolar range, while concentrations by one order of magnitude lower were found in saliva, but still within the detection limit. The results will serve as a basis for comparative studies of 7-hydroxydehydroepiandrosterone levels under various pathophysiological conditions, with a particular respect to autoimmune disorders.

Nanocellulose as Modifier for Hollow Fiber Ultrafiltration PSF Membranes

2019 ◽  
Vol 816 ◽  
pp. 238-243 ◽  
Author(s):  
Tatyana S. Anokhina ◽  
S.D. Bazhenov ◽  
Ilya L. Borisov ◽  
V.P. Vasilevsky ◽  
V.A. Vinokurov ◽  
...  
Keyword(s):  
Transport Properties ◽  
Hollow Fiber ◽  
Cellulose Nanofibrils ◽  
Membrane Modification ◽  
Selective Layer ◽  
Blue Dextran ◽  
First Time ◽  
Molding Solution

In the present work, a study was conducted for the first time on the modification of hollow fiber UF PSF membranes by cellulose nanofibrils. Two approaches to membrane modification were analyzed: 1) introduction of CNF into the molding solution; 2) additions of CNF to the internal coagulant. Analysis of the transport properties of the investigated membranes showed that the first approach allows increasing the porosity of hollow fiber PSF membranes, due to which the permeability increases from 82 to 287 l / m2 h bar compared to the original membranes. Rejection of dye Blue Dextran (MM = 69 kg / mole) is reduced by 20%. The addition of CNF to the outside coagulant led to the formation of not only the inside selective layer, but also the outer one, while the permeability increases 1.5 times, and the rejection of the dye also increases from 96 to 99%.

Ultra-Low Resistance Ni-Based Contacts to n-InP: the Dependence of Contact Resistivity on the Condition of the Metal-Semiconductor Interface

1993 ◽  
Vol 318 ◽  
Author(s):  
Navid S. Fatemi ◽  
Victor G. Weizer
Keyword(s):  
Deposition Process ◽  
Atomic Ratio ◽  
Contact Resistivity ◽  
Semiconductor Interface ◽  
Near Surface ◽  
Process Use ◽  
Fold Reduction ◽  
Specific Contact ◽  
Order Of Magnitude ◽  
First Time

ABSTRACTNear-theoretical-minimum values of specific contact resistivity, ρc (in the mid-to-low E-8 Ω-cm2 range) have been achieved for Ni-based contacts to moderately doped (2E18 cm−3) n-type InP. In each case these values are an order of magnitude lower than those previously achieved. These ultra-low resistivities are shown to result when the metallurgical interaction rate between the contact metal and the semiconductor is sufficiently reduced. Several methods of reducing the metal-InP reaction rate and thus achieving lowered resistivity values are demonstrated. We show, for instance, that the introduction of a thin (100Å) Au layer at the metal-InP interface retards metal-semiconductor intermixing during sintering and results in a ten-fold reduction in pc. Another method consists of ensuring the perfection of the near-surface InP lattice prior to and during contact deposition process. Use of this technique has enabled us to fabricate, for the first time, Ni-only contacts with pc values in the low E-8 Ω-cm2 range. We present an explanation for these observations that is based upon the magnitude of the In-to-P atomic ratio at the metal-InP interface.

A formalism for the indirect Auger effect. II

1976 ◽  
Vol 347 (1651) ◽  
pp. 565-573 ◽  
Keyword(s):  
Band Structure ◽  
Auger Recombination ◽  
Preceding Paper ◽  
Recombination Coefficient ◽  
Overlap Integrals ◽  
Estimated Parameters ◽  
Order Of Magnitude ◽  
Auger Effect ◽  
First Time ◽  
Auger Recombination Rate

The Auger recombination rate in indirect semiconductors with zincblende and diamond lattices is investigated, account being taken, for the first time, the properties of overlap integrals near symmetry points and axes. The effect of using theoretically estimated parameters is a reduction of the recombination coefficient by a factor 10. It is explained that the results, and those of the preceding paper, are still subject to uncertainties arising from the band structure so that only the order of magnitude of these coefficients can so far be regarded as known theoretically.

Transbilayer movement of fluorescent and spin-labeled phospholipids in the plasma membrane of human fibroblasts: a quantitative approach

1996 ◽  
Vol 109 (3) ◽  
pp. 687-698 ◽  
Author(s):  
T. Pomorski ◽  
P. Muller ◽  
B. Zimmermann ◽  
K. Burger ◽  
P.F. Devaux ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Initial Velocity ◽  
Plasma Membranes ◽  
Atp Hydrolysis ◽  
Human Fibroblasts ◽  
Atp Depletion ◽  
Aminophospholipid Translocase ◽  
Order Of Magnitude ◽  
Complicating Factors ◽  
First Time

All phospholipids in the plasma membrane of eukaryotic cells are subject to a slow passive transbilayer movement. In addition, aminophospholipids are recognized by the so-called aminophospholipid translocase, and are rapidly moved from the exoplasmic to the cytoplasmic leaflet of the plasma membrane at the expense of ATP hydrolysis. Though these principal pathways of transbilayer movement of phospholipids probably apply to all eukaryotic plasma membranes, studies of the actual kinetics of phospholipid redistribution have been largely confined to non-nucleated cells (erythrocytes). Experiments on nucleated cells are complicated by endocytosis and metabolism of the lipid probes inserted into the plasma membrane. Taking these complicating factors into account, we performed a detailed kinetic study of the transbilayer movement of short-chain fluorescent (N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl); NBD) and, for the first time, spin-labeled analogues of phosphatidylcholine (PC), -ethanolamine (PE), -serine (PS), and sphingomyelin (SM) in the plasma membrane of cultured human gingival fibroblasts. At 20 degrees C, the passive transbilayer diffusion of NBD analogues was very slow, and the choline-containing NBD analogues were internalized predominantly by endocytosis. Spin-labeled analogues of PC and SM showed higher passive transbilayer diffusion rates, and probably entered the cell by both passive transbilayer movement and endocytosis. In contrast, the rapid uptake of NBD- and spin-labeled aminophospholipid analogues could be mainly ascribed to the action of the aminophospholipid translocase, since it was inhibited by ATP depletion and N-ethylmaleimide pretreatment. The initial velocity of NBD-aminophospholipid translocation was eight to ten times slower than that of the corresponding spin-labeled lipid, and the half-times of redistribution of NBD-PS and spin-labeled PS were 7.2 and 3.6 minutes, respectively. Our data indicate that in human fibroblasts the initial velocity of aminophospholipid translocation is at least one order of magnitude higher than that in human erythrocytes, which should be sufficient to maintain the phospholipid asymmetry in the plasma membrane.

scholarly journals Size Distribution, Mechanical and Electrical Properties of CuO Nanowires Grown by Modified Thermal Oxidation Methods

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1051 ◽  
Author(s):  
Raitis Sondors ◽  
Jelena Kosmaca ◽  
Gunta Kunakova ◽  
Liga Jasulaneca ◽  
Matiss Martins Ramma ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Aspect Ratio ◽  
Electric Field ◽  
Thermal Oxidation ◽  
Size Distribution ◽  
High Aspect Ratio ◽  
Growth Conditions ◽  
Cuo Nanowires ◽  
Young’S Moduli ◽  
Order Of Magnitude

Size distribution, Young’s moduli and electrical resistivity are investigated for CuO nanowires synthesized by different thermal oxidation methods. Oxidation in dry and wet air were applied for synthesis both with and without an external electrical field. An increased yield of high aspect ratio nanowires with diameters below 100 nm is achieved by combining applied electric field and growth conditions with additional water vapour at the first stage of synthesis. Young’s moduli determined from resonance and bending experiments show similar diameter dependencies and increase above 200 GPa for nanowires with diameters narrower than 50 nm. The nanowires synthesized by simple thermal oxidation possess electrical resistivities about one order of magnitude lower than the nanowires synthesized by electric field assisted approach in wet air. The high aspect ratio, mechanical strength and robust electrical properties suggest CuO nanowires as promising candidates for NEMS actuators.

Graphite/UPE Nanocomposite: Transport, Thermal, Mechanical and Viscoelastic Properties

2019 ◽  
Vol 23 ◽  
pp. 201-212
Author(s):  
Shivkumari Panda ◽  
Dibakar Behera ◽  
Tapan Kumar Bastia
Keyword(s):  
Transport Properties ◽  
Unsaturated Polyester ◽  
Homogeneous Distribution ◽  
Thermo Gravimetric ◽  
New Class ◽  
The Matrix ◽  
Novel Method ◽  
Water Transport Properties ◽  
First Time

This chapter presents the preparation and characterization of some unique properties of nanocomposites by dispersing graphite flakes in commercial unsaturated polyester (UPE) matrix. The composite was prepared by a novel method with the use of solvent swelling technique. Three different specimens of UPE/graphite nanocomposites were fabricated with addition of 1, 2 and 3 wt% of graphite flakes. Except mechanical, viscoelastic and thermo gravimetric properties, transport properties like electrical conductivity, thermal conductivity and water transport properties were studied for the first time. Graphite flakes propose enhanced properties to the composites suggesting homogeneous distribution of the nanofiller in the matrix and strong interaction with the matrix. 2wt% nanofiller loading showed superior essential characteristics and after that the properties reduced may be due to the nucleating tendency of the nanofiller particles. The XRD pattern showed the compatibility of the graphite flakes by introducing a peak around 26.550 in the nanocomposites. SEM Properties are also in agreement with the compatibility. Nanocomposite with 2wt% graphite also showed remarkable enhancement in transport, mechanical, viscoelastic and thermo gravimetric properties. So by introduction of a small quantity of graphite endow the new class of multiphase nanocomposites with inimitable structure and tremendous application.

scholarly journals New metal-oxide composite materials as efficient catalysts of the partial oxidation of methane

2019 ◽  
Vol 484 (3) ◽  
pp. 299-302
Author(s):  
A. G. Dedov ◽  
O. A. Slyakhtin ◽  
A. S. Loktev ◽  
G. N. Mazo ◽  
S. A. Malyshev ◽  
...  
Keyword(s):  
Partial Oxidation ◽  
Single Phase ◽  
Complex Oxides ◽  
Partial Oxidation Of Methane ◽  
Metallic Nickel ◽  
Oxidation Of Methane ◽  
Nickel Cobalt ◽  
Phase Complex ◽  
First Time ◽  
Properties Of Composites

Single-phase complex oxides Nd2-yCayCoxNi1-xO4 have been synthesized for the first time. Composites prepared by the reduction of these compounds with hydrogen and containing Nd2O3, CaO, and cobalt and nickels metals have been used for the first time as catalysts of the partial oxidation of methane. The maximal methane conversions (97%) and syngas yields (96%) at 900 °С have been detected in the presence of the composite obtained from Nd1,5Ca0,5NiO4. At T < 850 °C, the nickel–cobalt composite synthesized from Nd1,3Ca0,7Co0,4Ni0,6O4 turned out to be more selective in the formation of syngas. Decreasing the partial oxidation temperature from 900 °С to 750 °С leads to the oxidation of metallic nickel and cobalt to oxides and to partial resynthesis of complex oxides with perovskite and K2NiF4 structures. The observed differences in temperature dependence of the catalytic properties of composites with various Ni/Co ratios can be associated with the participation of complex oxides in catalysis of the partial oxidation of methane at low temperatures.

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