The possibility of chemical metallization of the surface of poly(ethylene terephthalate) (lavsan) fibers in solutions using hydrazine sulfate as a reducing agent is shown. As a result, a conductive ...material is obtained. The surface of lavsan fibers is activated by treating the fibers in caustic ammonia with ultrasound treatment and processed in alkaline solutions. The elemental composition and surface morphology of the metalized fibers are characterized using X-ray diffraction, microprobe analysis, and scanning electron microscopy. The surfaces of metallized fibers treated with various copper-plating solutions are shown to be coated by copper layers of 4 μm thickness, having good adhesion. The coating is uniform and defect-free over the entire length of the fibers. The fiber electrical resistivity is 0.4–0.9 Ω/cm.
Chemical Copper Coating of Lavsan Fibers Pakuro, N. I.; Rybakova, L. F.; Nakhmanovich, B. I. ...
Fibre chemistry,
11/2017, Letnik:
49, Številka:
4
Journal Article
Recenzirano
A method for chemical deposition of thin copper coatings on lavsan fibers was developed using reduction of copper salts in alkaline solution in the presence of complexants. Sodium borohydride was ...used as the reductant. A nondestructive method for preliminary modification of the lavsan fibers with surface polar groups was found. Studies of the effect of the copper-salt anion on fiber metallization found that the use of copper acetate was most effective. X-ray phase analysis and electron-probe microanalysis found that the formed coating consisted of pure copper without impurities of oxides or other elements. SEM studies of the surface morphology of the copper-coated fibers showed that the obtained continuous coating consisted of Cu crystal agglomerates of dimensions ~500 nm. The metallized lavsan fibers had high electrical conductivity.
Bismuth ferrite films on single-crystal lanthanum aluminate substrates have been grown for the first time through spray pyrolysis of iron and bismuth methacrylate solutions. The film growth process ...comprises two steps: liquid-phase and crystalline (including pyrolysis). In the liquid-phase step, we analyzed the elemental composition and surface morphology of the coatings as functions of substrate temperature. In the pyrolytic and high-temperature steps, we analyzed the elemental composition and crystal structure of the films as functions of substrate and annealing temperatures. Conditions were established for the growth of partially oriented films.
Solid solutions of Bi
1 −
x
Pb
x
Fe
1 −
x
Zr
x
O
3
(
x
= 0.1−0.2) are synthesized by the methods of liquid-phase and modified solid-phase synthesis. Also, solid solutions of Bi
0.9
(Pb
0.9
Ln
0.1
)
...0.1
Fe
0.9
(Zr
0.65
Ti
0.35
)
0.1
O
3
, and Bi
0.9
(Pb
0.9
Ln
0.1
)
0.1
Fe
0.9
(Zr
0.53
Ti
0.47
)
0.1
O
3
(Ln - La, Pr, Gd, Yb) are made, including synthesis of their precursors with organic ligands. Comprehensive investigations involving thermal analysis, IR spectroscopy, X-ray powder diffraction, atomic force microscopy, dielectric and magnetic measurements, and neutron powder diffraction are performed. The full-profile analysis of X-ray and neutron diffraction patterns by the Rietveld method shows that, over the whole temperature interval of 10–700 K under study, the Bi
0.9
Pb
0.1
Fe
0.9
Zr
0.1
O
3
and Bi
0.8
Pb
0.2
Fe
0.8
Zr
0.2
O
3
compounds are characterized by the perovskite structure (space group
R
3
c
). The magnetic measurements reveal an antiferromagnetic phase transition in the Bi
0.9
Pb
0.1
Fe
0.9
Zr
0.1
O
3
and Bi
0.8
Pb
0.2
Fe
0.8
Zr
0.2
O
3
solid solutions. The Néel temperature (
T
N
) decreases considerably with growing PbZrO
3
concentration as compared to the Néel point in pure BiFeO
3
(
T
N
= 633 K). The perovskite structure with a hexagonal distortion is found in lanthanide-substituted solid solutions and specific features of the surface morphology of the ceramics are analyzed. The magnetic measurements suggest the presence of an antiferromagnetic phase transition in the solid solutions under study, with a considerable drop of
T
N
in the Ln-alloyed compound as compared to the
T
N
value in pure BiFeO
3
(Pb
1 −
x
Ln
x
)(Zr
0.53
Ti
0.47
)O
3
and (Pb
1 −
x
Ln
x
)(Zr
0.65
Ti
0.35
)O
3
(
x
= 0.02, 0.06; Ln = La, Pr, Gd, Yb) solid solutions have been prepared by modified solid-state synthesis using ...organic-ligand precursors. The solid solutions have been characterized by thermal analysis, IR spectroscopy, x-ray powder diffraction, and atomic force microscopy. All of them have a rhombohedrally distorted perovskite structure (sp. gr.
R
3
c
).
The polymerization of 1-butene over the TiCl
4
/MgCl
2
(TMC) catalyst with the use of substituted phosphine oxides R
n
P(O)(CH
2
OR′)
3 −
n
(R = alkyl, R′ = methyl or acyl,
n
= 0–2)—new external ...electron donors-has been investigated. The electron-donating (coordinating) centers in these compounds are the phosphoryl group (P=O) and the oxygen atoms of the substituents at the phosphorus atom. The dependence of the 1-butene polymerization activity of TMC on the nature of the substituents in the phosphine oxides has been studied. The microstructure, degree of crystallinity, molecular weight, and strain-strength characteristics of the synthesized polybutene-1 and the effect of hydrogen on these properties are reported. The most efficient external donor is Me
2
P(O)CH
2
OAc.
Continuous, phase-pure, oriented yttrium barium cuprate (YBa
2
Cu
3
O
7
) films have been grown by deposition from metalorganic solutions onto lanthanum aluminate substrates and a nickel-tungsten ...tape with a barrier ceria layer. A “through” process has been used in which a ceria barrier layer and yttrium barium cuprate film grow from chemical solutions. In all steps of the process, the elemental composition of the deposits (Y: Ba: Cu molar ratio) was close to 1: 2: 3. The nanometer-scale structural evolution and phase formation in the YBa
2
Cu
3
O
7
films have been studied in detail. Depending on synthesis conditions, yttrium barium cuprate films may consist of three-dimensional, platelike, or flaky micro- and nanocrystallites. The degree of orientation of the atomic lattice of the targeted film may vary from partial ordering to a planar texture with an 〈001〉 axis normal to the substrate and with a pronounced azimuthal orientation of the crystallites. The degree of orientation was higher when trifluoroacetate solutions were used.
Ferroelectric-superconductor heterostructures consisting of a ferroelectric Pb-Ti-Zr-O film on a superconducting Bi-Sr-Ca-Cu-0 ceramic substrate or a superconducting Bi-Sr-Ca-Cu-O film on a ...ferroelectric Pb-Ti-Zr-O ceramic substrate with Ag, Au, Pd, and Pt barrier layers are prepared and investigated. Thinfilm Bi2Sr2CaCu2O8+x/ZrO2/Pb(Ti0.6Zr0.4)O3 (superconductor/barrier/ferroelectric) heterostructures on LaAlO3 substrates are for the first time produced and characterized. The superconducting and ferroelectric transition temperatures in the heterostructures are 80 and 638 K, respectively.
8-Hydroxy(methoxy)-substituted 2-6-(1-methylindol-3-yl)pyridin-2-ylquinoline ligands were synthesized by means of combination of S
N
H
reaction between 8-methoxy-substituted ...2-(6-aryl-1,2,4-triazin-3-yl)quinolones and indole and aza-Diels–Alder reaction of the obtained 1,2,4-triazines with 2,5-norbornadiene. The demethylation of quinoline moiety of 1,2,4-triazine precursor during aza-Diels–Alder reaction in autoclave was demonstrated.
We have studied nanoscale structural evolution processes and phase formation in barrier cerium oxide layers grown from methacrylate solutions on lanthanum aluminate and a nickel-tungsten tape by dip ...coating. The layers were characterized by atomic force microscopy, scanning electron microscopy, precision electron diffraction, X-ray microanalysis, and X-ray diffraction (including texture analysis). We have investigated nanostructured morphological forms of buffer cerium oxide layers in all synthesis steps: liquid-phase, pyrolytic, and crystalline. We have established a granular character of the nanostructure and determined the type of orientation of the films: 〈111〉 texture with a 〈200〉 additional orientation. Optimal conditions for the synthesis of a barrier layer several tens of nanometers in thickness are proposed.
