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In this paper, using the solid-state reaction technique, high-temperature nanomaterial's superconductors HgBa2Ca2Cu3O8+δ and HgBa2CaCu2O6+δ, have been effectively created. At 850 °C, samples were sintered. By calculating the current and voltage as a function of temperature using the four probes method to determine the transition temperatures Tc(onset) and Tc(offset), the continuous electrical properties were explored. Where it was discovered that for the HgBa2Ca2Cu3O8+δ compound, the electrical resistivity has a gradient Tc(onset) (the beginning) at 145 K but zeroes out at Tc(offset) = 128 K. The temperature Tc(onset) (beginning) for the HgBa2CaCu2O6+δ compound was 137 K, whereas the temperature Tc(offset) was zero at 115 K. Using a Lee disk, thermal conductivity was measured. It was found that the thermal conductivity increased in direct proportion to temperature. The sample of the compound (HgBa2Ca2Cu3O8+δ) (Hg-1223) has a curve that begins at a temperature (40 ° C), thermal conductivity (0.878970388), and ends at a point (0.901118234) with a temperature (280 °C). This curve is higher than the curve of the compound (HgBa2CaCu2O6+δ) (Hg-1212) has a curve that begins at a temperature (40 ° C), thermal conductivity (0.878027444), and ends at a point (0.895530) with a temperature (280 °C). In order to analyze the structural qualities, X-ray diffraction analysis was used. The findings demonstrated that both compounds have a tetragonal crystal structure with distinct differences in the crystal lattice characteristics. [ABSTRACT FROM AUTHOR]

In this study, the molten method was used to prepare the chalcogenide compound Ge35−S65-X−CdX. Five samples were obtained by partial replacement of sulfur with cadmium in the weight ratios x = 0, 5, 10, 15and 20, respectively. The materials were mixed separately, ground, placed in quartz ampoules, and heated to 900 degrees Celsius. After conducting several operations on the samples, their insulating properties were studied, represented by the real dielectric constant and the imaginary dielectric constant. The loss remained in a frequency range ranging from (50_1000000 Hz). It was found that partial replacement plays an important role in enhancing the insulating properties. [ABSTRACT FROM AUTHOR]

In order to analyze the structural properties of the HgBa2Ca2Cu3O8+δ sample, X-ray diffraction was used. To determine the type of crystal structure, the results showed that the compound has a tetragonal crystal structure. The crystal lattice constants (a, b, c) were calculated with obvious differences in the crystal lattice properties. The crystal size was calculated by four different methods (Scherrer, Williamson-Hall, Halder-Wagner and size-strain plot), which showed the best result using the (Halder-Wagner) method, where the crystal size (C.S=22.27 nm) and determination coefficient (R=0.9903), which is the best method among the four methods for preparing this compound. The titration method of the samples (HgBa2Ca2Cu3O8+δ) was used to find out the percentages of oxygen content (δ) and it was found that the oxygen content was (δ=0.269). And by using the four probes method to determine the transition temperature, it was found that the transition temperature (Tconset) is equal to (147K), where the electrical resistance begins with a strong gradient and becomes zero at the critical temperature (Tcoffset = 128K). The thermal properties were studied using the(Lee's disk) method, the results showed that the thermal conductivity of the sample decreases whenever the temperature is applied to it, as the compound is characterized by a thermal curve that begins to show thermal conductivity at (0.12945) at temperature (313K) and the curve decreases to (0.09888) at temperature (553K). The dielectric properties of the compound were examined using a device (LCR counter) which included: dielectric constant (real and imaginary), loss factor and alternating electrical conductivity, the dielectric properties were studied as a function of frequency and range (50 Hz) to (1 MHz) at room temperature. [ABSTRACT FROM AUTHOR]

The current work includes studying the effect of partial substitution of antimony nanoparticles instead of bismuth on the electrical and structural properties of the superconducting compound Bi2-xSbxBa2Ca2Cu3O10+δ, where x = 0, 0.1, 0.2, 0.3, and the samples were prepared by the solid state reaction (SSR) method. The samples were sintered in normal air and at a temperature of 800°C for 48 hours at a heating rate of 10°C/min. X-ray diffraction tests were carried out on the four samples of different antimony concentrations. The results showed that all samples had a orthotropic structure, with differences in the lattice constants (a, b and c,)with a clear increase in the dimension c = 36.6899 A° for the second sample when x = 0.1, as well as an increase in the percentage of the high phase HTP%, which equals 68.16%, and the formation of And the structure (morphology) by the SEM device for the samples, the formation of a granular size with Nano-dimensions was observed, and the element analysis for each sample was examined through EDS examination, as the results showed the presence of the elements and their different proportions in each sample. [ABSTRACT FROM AUTHOR]

In this paper, Se60Te40-xSnx chalcogenide glasses with different concentrations of Tin (x=0, 5, 10, 15 and 20) were prepared) by melting point method. The electrical properties, i.e. electrical conductivity as a function of temperature, were studied. The activation energy was calculated and was found that at the extended state it changes from 0.223 to 0.281, local state, the activation energy changes from 0.159 to 0.306 and at the Fermi level; it is found that it changes from 0.151 to 0.231. As for the width of energy tails, they are decreasing, and this indicates that the randomness of the compound is decreased, meaning that it has become more crystalline. The Energy density of state the extended, localized, at Fermi energy and the effect of adding Sn on it also was calculated. The increase in Tin (Sn) concentration led to a change in the density of extended, localized, and at Fermi level. it was found that the extended levels changed from 1.650x1024 to 6.226x1025, localize state, they change from 2.881x1020 to 2.113x1024, as for Fermi level, the density of states changed from 5.033x1021 to 1.942x1023 when the Tin concentration increased from 0 to 20. [ABSTRACT FROM AUTHOR]

In this paper, the Se60Te40-xsbx compound was prepared with different concentrations of antimony (Sb) (where x = 0, 5, 10, 15, 20) by melting point method. The electrical measurements of semiconductors were studied by analyzing the results of electrical conductivity as a function of temperature. The Moot-Davis model has been adopted as the emblem of three mechanisms that can control the conduction of electrons through amorphous semiconductors. The densities of energy states extended, localized and at Fermi level were calculated for different samples of antimony. It was Found that the extended states changed from 1.650 × 1024 to 2.159 × 1027, while local states, it changed from 2.881 × 1020 to 5.259 × 1023, as for the Fermi level, the density of states changed from 5.033 × 1021 to 1.571 × 1021 when the antimony concentration increased from 0 to 20 respectively. The activation energy was also calculated and found that in the extended state it changes from 0.223 to 0.557, and for the local case, the activation energy changes from 0.159 to 0.515 and at the Fermi level it changes from 0.151 to 0.332 when the antimony concentration is increased from zero to 20. As for the width of the energy tails, it was found that they are in a decreasing state, and this indicates that the randomness of the compound is decreasing, that is, it has become more crystalline. [ABSTRACT FROM AUTHOR]

In this paper, the Se60Te40-xsbx compound was prepared with different concentrations of antimony (Sb) (where x = 0, 5, 10, 15, 20) by melting point method. The electrical measurements of semiconductors were studied by analyzing the results of electrical conductivity as a function of temperature. The Moot-Davis model has been adopted as the emblem of three mechanisms that can control the conduction of electrons through amorphous semiconductors. The densities of energy states extended, localized and at Fermi level were calculated for different samples of antimony. It was Found that the extended states changed from 1.650 × 1024 to 2.159 × 1027, while local states, it changed from 2.881 × 1020 to 5.259 × 1023, as for the Fermi level, the density of states changed from 5.033 × 1021 to 1.571 × 1021 when the antimony concentration increased from 0 to 20 respectively. The activation energy was also calculated and found that in the extended state it changes from 0.223 to 0.557, and for the local case, the activation energy changes from 0.159 to 0.515 and at the Fermi level it changes from 0.151 to 0.332 when the antimony concentration is increased from zero to 20. As for the width of the energy tails, it was found that they are in a decreasing state, and this indicates that the randomness of the compound is decreasing, that is, it has become more crystalline. [ABSTRACT FROM AUTHOR]

In this paper, the Tl1-xHgxSr2Ca2Cu3O8+δ compound with X=(0.0, 0.1, 0.2, 0.3 and 0.4) was prepared by using the method of solid-state. The electrical resistivity was studied using the four probes technique to find the transition temperature at zero resistance Tc(off) and at translation Tc(on). Tc (off) and Tc (on) increased from 103 to 133 K and 112 to 135 K with an increase in mercury concentration from 0 to 0.4, respectively. The sample crystal structure was studied using an X-ray diffraction device. The X-ray diffraction (XRD) study of the crystalline nature confirmed that the sample of the compound has a lattice structure of a mixture of different phases, it has a tetragonal. The traditional Debye-Scherrer method and the methods modified for it were calculated and investigated from the crystal size. It is noted the approximate values of crystal size and crystallinity in percentage between the two modified Scherer methods and the traditional Scherer method change depending on the intensity picks of the XRD diagram. Furthermore, the sample was taken into account to determine the physical and microstructure factors such as strain. [ABSTRACT FROM AUTHOR]

This article is focused on studies of partially substituted mercury by red lead for Hg 1-x Pb x Ba 2 Ca 2 Cu 3 O 8+δ compound with X= (0.05, 0.1, 0.15, 0.2 and 0.25) was prepared by the solid state reaction method. The electrical properties were studied using the four points probe technique to determine the critical temperatures of the samples and to know the effect of partial substitution of mercury with red lead on them. It was found that both the critical temperatures and the energy gap were slightly affected by partial substitution. Where the values of the critical temperatures were obtained (critical temperature, Tc(offset) = 117.1, 121.9, 121.1, 120.1, 117.6 and 113.4 K with X= (0.05, 0.1, 0.15, 0.2 and 0.25), respectively. And the maximum value of critical temperature Tc(offset) is 121.9 K for the compound Hg0.95Pb0.05Ba2Ca2Cu3O8+δ. Energy gap increase to 3.71x 10−3 when the Red Lead concentration increasing from 0 to 0.15, after this state noted rapid down until 0.25 concentration. [ABSTRACT FROM AUTHOR]

Five samples of Bi2-xPbxSr2Ca.2Cu3O10+δ with x=0, 0.1, 0.2, 0.3 and 0.4 have been prepared by solid state reaction process. The powder was pressed to pellets with (one cm) in diameter under a hydrostatic pressure about (8 tons/cm2). The pellets were then put in a furnace which has a programmable controller for sintering, and were sintered in air at 855-860 °C for 72 hours with a rate of '100 °C /h, and then were cooled to room temperature by same rate of heating. Electrical properties were studied., Electrical resistivity, using the four probe technique, was used to find the transition temperature at zero resistivity (Tc(off)) and on set (Tc(on)), The transition temperature Tc(off) and Tc(on) were increasing from 106 to 131 K and 113 to 138 K by increasing lead from 0 to 0.4, respectively. X-ray diffraction (XRD) analysis showed all our samples have orthorhombic structure correspond to the 2223 phase, with increasing of the intensity by increasing lead. [ABSTRACT FROM AUTHOR]

In the present study we have reported realization simultaneous effect substitution of Hg at the Tl layer of Cu0.5 (TL0.5-xHgx) Ba2Ca2Cu3+O10+δ superconductor. Samples have been prepared using solid state reaction method. The partial substitution of the Hg in Tl metal of the compound has been investigated where x = 0 , 0.1 , 0.2,0.3 and 0.4. Four probe techniques was using to find the transition temperature Tc. It was found that the critical temperatures at zero resistivity Tc(Offset) were 127.75, 131.95, 137.07, 136.3 and 117.2K and Tc(on) were 96.0,115.0, 135.15, 122.4 and 119.1K for x=0, 0.1,0.2, 0.3 and 0.4 respectively. The X-ray diffraction study showed that all prepared samples have a tetragonal structure, with a clear change in the constants of lattice with Tl-substituted samples compared to this without Tl. It has also been found that a change in the concentrations of Tl leads to a change in, c / a. Cu0.5 (TL0.5-xHgx) Ba2Ca2Cu3+O10+δ phase development was observed. [ABSTRACT FROM AUTHOR]