X-ray diffraction studies on oxide-superconductors under pressure by a new X-ray detection system

Charged-coupled device (CCD) detectors have been widely accepted as detectors for collecting X-ray diffraction images. The CCD detector offers a sensitive detection system well suited for diffraction analysis and, compared with other detectors on the market, a relatively rapid system for read-out of the collected image. The two predominant markets for the CCD detector have been those in which relatively short exposure times are used,i.e.small-molecule X-ray diffraction and large-molecule crystallography at high-intensity synchrotron sources. CCD detectors have not been commonly used on rotating-anode X-ray sources for large-molecule crystallography. Comparison of the performance of the CCD detectors with commercially available image-plate detectors shows that the CCD detectors function in a similar fashion to image-plate-based detectors.

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Fluorescent lamp tungsten filament thermionic emission gun as a novel humidity optical sensor

10.21203/rs.3.rs-434123/v1 ◽

2021 ◽

Author(s):

Leila Sherafat ◽

Hossein Torabi-Monfared ◽

Mohammad Mahdi Doroodmand ◽

Fazlolah Eshghi

Keyword(s):

Optical Sensor ◽

Food Processing ◽

Detection System ◽

Thermionic Emission ◽

Fluorescent Lamp ◽

Health Food ◽

X Ray Diffraction ◽

Tungsten Filament ◽

X Ray ◽

Relative Standard

Abstract Detecting humidity is a continuing concern within important area such as structural health, food processing, industrial as well agricultural products. In this study, a novel humidity optical sensor is introduced based on the thermionic emission of tungsten filament of a fluorescent lamp. Estimated blue compliant using a charged coupling device camera (CCD) in optical image of the tungsten filament is considered as appropriate detection system for relative humidity (RH) sensing. . The fabricated optical sensor has acceptable linear range (2.0- 98 % RH), improved detection limit (<5.0 % RH), acceptable saturated limit (> 99.0 % RH), improved percentage of relative standard deviation (4.18%, n=2), adequate hysteresis (<4.0 % RH) and a shorter rise time (<5.0 s), respectively. The mechanism behind this detection system was based on the interaction between H2O and tungsten filament during formation of WO3.x H2O (x = 1-2) based on the patented X-ray diffraction analysis.

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EFFECT OF SUBSTITUTION OF Na, Cd, Bi for Ca in Bi-Sr-Ca-Cu OXIDE SUPERCONDUCTORS

Modern Physics Letters B ◽

10.1142/s0217984989001448 ◽

1989 ◽

Vol 03 (12) ◽

pp. 939-944 ◽

Cited By ~ 5

Author(s):

YU MEI ◽

S.M. GREEN ◽

C. JIANG ◽

H.L. LUO ◽

C. POLITIS

Keyword(s):

Solid State ◽

Normal State ◽

Solid State Reaction ◽

Oxide Superconductors ◽

X Ray Diffraction ◽

Normal State Resistivity ◽

X Ray

Samples with compositions Bi 1.8 Pb 0.2 Sr 2( Ca 2−x Na x) Cu 3 O y, BiSr(Ca 1−x Cd x) Cu 2 O y and BiSr ( Ca 1−x Bi x) Cu 2 O y were prepared through solid state reaction. The X-ray diffraction results were analyzed and their resistivity behavior was studied. In general, all such substitution adversely affected their superconductive properties. All samples are of multiphase. The normal state resistivity behaves quite differently with the substitution of electropositive Na as compared with the replacement of electronegative Bi.

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OXIDE SUPERCONDUCTIVITY RESEARCH AT NORTHWESTERN UNIVERSITY

International Journal of Modern Physics B ◽

10.1142/s0217979287001183 ◽

1987 ◽

Vol 01 (03n04) ◽

pp. 829-829

Author(s):

J.B. KETTERSON

Keyword(s):

Electrical Transport ◽

Short Review ◽

Argon Atmosphere ◽

Oxide Superconductors ◽

X Ray Diffraction ◽

X Ray ◽

Transport Studies ◽

Wide Range ◽

Northwestern University ◽

Zero Resistance

A short review was presented of a wide range of activities involving the high Tc oxide superconductors at the Northwestern University. Calculations of the charge density associated with the d9 shell of the copper atom in the Cu-O planes and the d8 shell of the copper atoms along the Cu-O lines of the unit cell of YBa2Cu3O7 performed by Freeman, Massida and Yu were presented. Results of a detailed study of the pseudoternery phase diagram involving CuO, BaO and YO1.5 were shown which verify the existence of three compounds having the Y:Ba:Cu ratios 123 (the high Tc superconductor), 211 (the so-called green phase) and 132 (a new insulating compound). This work, performed by Mason and coworkers, involved X-ray diffraction, optical spectroscopy, magnetic susceptibility, and electrical transport studies. Transport measurements by Poeppelmeier, Song, Hwu and coworkers on the assembledges YBaSrCu3O7 anf YBa2Cu3O5F2 were reported; no evidence of superconducting behavior at temperatures above 90K was seen in the latter. A detailed study of the magnetic and transport properties of the YBa2−xLaxCu3−xNixO7±δ system was reported. For small Ni concentration (x<0.3) a continuous drop in Tc was observed. For x= 0.4 and 0.5 evidence of two separate transitions, near 75K and 25K, were seen in the resistance (with the resistance going to zero at about 15K); for x=0.7 semiconducting behavior was observed. A continuous drop in the normalized diamagnetic signal was seen with increasing x with the diamagnetic fraction being below 5 % for x=0.7 and above. X-ray diffraction showed a continuous decrease in the orthorhombic fraction and an increase in the tetragonal fraction with increasing x. Results on d.c. magnetron sputtering of thin films on MgO from a stoichiometric 123 target in an argon atmosphere were shown. With proper annealing films with onset temperature of 90K and zero resistance at 68K have been prepared; this work was done by Jin, Lee, Song and coworkers. A brief report on the effect of O-stoichiometry on EPR and susceptibility measurements in the 123 compound performed by Hoffman and coworkers and NMR in the La2−xSrxCuO4 compound by Halpern and coworkers was presented.

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Fluorescent lamp tungsten filament thermionic emission gun as a novel humidity optical sensor

Scientific Reports ◽

10.1038/s41598-021-97688-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hossein Torabi-Monfared ◽

Leila Sherafat ◽

Mohammad Mahdi Doroodmand ◽

Fazlolah Eshghi

Keyword(s):

Optical Sensor ◽

Detection System ◽

Thermionic Emission ◽

Fluorescent Lamp ◽

Health Food ◽

X Ray Diffraction ◽

Tungsten Filament ◽

X Ray ◽

Relative Standard ◽

Set Up

AbstractDetecting humidity have been remained a continuing concern within some important areas such as structural health, food processing, industrial as well as agricultural products. In this study, a novel humidity optical sensor is introduced based on the thermionic emission of tungsten filament using the fluorescent lamp set-up. Estimated blue compliant using a charged coupling device camera in optical image of the tungsten filament was confirmed as an appropriate detection system for relative humidity (RH) sensing. The fabricated optical sensor has wide linear range (2.0–98% RH), improved detection limit (< 5.0% RH), acceptable saturated limit (> 99.0% RH), improved percentage of relative standard deviation (4.18%, n = 2), adequate hysteresis (< 4.0% RH) and a shorter rise time (< 5.0 s), respectively. The mechanism behind this detection system is based on the interaction between H2O and tungsten filament during formation of W$${\mathrm{O}}_{3}$$ O 3 .x $${\mathrm{H}}_{2}$$ H 2 O (x = 1–2) in terms of some spectroscopic obtained evidences as well as Fourier transform infrared and X-ray diffraction spectrometries.

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Improvement in Fabrication of Hg-1223 Superconductor by Te-Doping

MRS Proceedings ◽

10.1557/proc-659-ii9.9 ◽

2000 ◽

Vol 659 ◽

Author(s):

K.K. Yau ◽

C.C. Lam ◽

L.J. Shen ◽

S.H. Li

Keyword(s):

Critical Temperature ◽

Vapour Pressure ◽

Quartz Tube ◽

Mercury Vapour ◽

Oxide Superconductors ◽

Mass Ratio ◽

X Ray Diffraction ◽

Laboratory Environment ◽

X Ray ◽

Copper Oxide Superconductors

ABSTRACTThe sealed quartz tube method is one of the usual methods used for sintering mercury-based copper oxide superconductors. By this method, precursor pellets are inserted into the quartz tube together with certain mass ratio to the reagent sample pellets for controlling the mercury vapour pressure. A certain amount of excess HgO is required to ensure the fabricated sample to have the desired composition. In our research, it was found that if a small amount of TeO2 is added and mixed with the pulverized precursor after first calcination, Hg-1223 superconductors can be fabricated without using the precursor pellet and no excess HgO is required. Thus, the fabrication process can be simplified. As mercury and its oxide are toxic, if no excess Hg is involved, it is safe and good for the laboratory-environment. In this research, some amounts of 0.10 and 0.18 wt% (weigh percentage) of TeO2 were added into the precursor, it is shown that the critical temperature of the fabricated samples is comparable to that of the undoped Hg-1223 samples. For 0.10 wt% of TeO2, the Tc of the as-synthesized sample is about 116.7 K whereas the annealed Te-doped Hg-1223 is about 134.2 K. For 0.18 wt% of TeO2, the Tc of the as- synthesized and annealed samples are 115.8 K and 134.6 K, respectively. The phase structure of samples fabricated in this research has been analyzed by the X-ray diffraction technique. It shows that the Hg-1223 phase is dominated.

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Grazing Incidence X-ray Diffraction Studies of Thin Films Using an Imaging Plate Detection System

Langmuir ◽

10.1021/la950454n ◽

1996 ◽

Vol 12 (3) ◽

pp. 774-777 ◽

Cited By ~ 8

Author(s):

Garry J. Foran ◽

Jian Bang Peng ◽

Roland Steitz ◽

Geoffrey T. Barnes ◽

Ian R. Gentle

Keyword(s):

Thin Films ◽

Detection System ◽

Grazing Incidence ◽

Imaging Plate ◽

X Ray Diffraction ◽

X Ray

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NUCLEAR MAGNETIC RESONANCE STUDY OF 205Tl IN MULTIPHASE Tl-Ba-Ca-Cu OXIDE SUPERCONDUCTORS

International Journal of Modern Physics B ◽

10.1142/s0217979288001074 ◽

1988 ◽

Vol 02 (05) ◽

pp. 1227-1234 ◽

Cited By ~ 1

Author(s):

L. Mihály ◽

K. Tompa ◽

I. Bakonyi ◽

P. Bánki ◽

É. Zsoldos ◽

...

Keyword(s):

Room Temperature ◽

Relaxation Times ◽

Lattice Relaxation ◽

Nuclear Magnetic Resonance Study ◽

Spin Lattice Relaxation ◽

Oxide Superconductors ◽

X Ray Diffraction ◽

Magnetic Resonance Study ◽

X Ray ◽

Spin Lattice

Several batches of T l- Ba - Ca - Cu oxide superconductors have been synthesized and characterized by resistivity, magnetic susceptibility and X-ray diffraction measurements. The 205 T l NMR line snifts (K), the spin-lattice and spin-spin relaxation times have been measured at room temperature. The temperature dependence of the spin-lattice relaxation rate is also reported. The resonance around K = 0.25 % has a composite line shape indicating the presence of two T l sites. The two sites are tentatively assigned to thallium atoms in the (2223) and (2212) T l- Ba - Ca - Cu phases.

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ANOMALIES OF CELL PARAMETERS BEFORE SUPERCONDUCTING TRANSITION FOR BISMUTH BASED OXIDE SUPERCONDUCTOR

Modern Physics Letters B ◽

10.1142/s0217984989001084 ◽

1989 ◽

Vol 03 (09) ◽

pp. 685-693 ◽

Cited By ~ 2

Author(s):

S.L. YUAN ◽

W.Y. GUAN ◽

Z.J. CHEN ◽

Y.L. HUANG ◽

Y.B. JIA ◽

...

Keyword(s):

Phase Transition ◽

Diffraction Analysis ◽

Low Temperatures ◽

Structural Phase ◽

Oxide Superconductors ◽

Superconducting Transition ◽

Oxide Superconductor ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters

The results of X-ray diffraction analysis at low temperatures for bismuth-based high-Tc oxide superconductors are reported in this letter. There is no significant structural phase transition during superconducting transition. However, it appears that the cell parameters change anomalously before superconducting transition. This anomalous change in cell parameters is repeated for different bismuth-based high-Tc oxide superconductors.

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Electrical, Chemical, and Structural Properties of Plasma Sprayed Y-Ba-Cu-Oxide Superconducting Coatings

MRS Proceedings ◽

10.1557/proc-99-689 ◽

1987 ◽

Vol 99 ◽

Cited By ~ 9

Author(s):

R. A. Neiser ◽

J. P. Kirkland ◽

W. T. Elam ◽

H. Herman ◽

S. Rangaswamy ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Chemical Composition ◽

Oxide Superconductors ◽

X Ray Diffraction ◽

Properties Of Coatings ◽

X Ray ◽

Lattice Constants ◽

Spray Processing ◽

Plasma Sprayed ◽

Thick Coatings

ABSTRACTThick coatings of Y-Ba-Cu-oxide superconductors have been prepared by plasma spray processing. This paper reports a number of the important properties of coatings sprayed at two different power levels. The microstructure, porosity, and chemical composition of the coatings were studied in their as-sprayed and annealed states. Critical current and magnetic susceptibility measurements were made on the annealed coatings. X-ray diffraction was used to identify non-superconducting phases present in the coatings and to determine the superconducting phase's lattice constants.

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