The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
D. H. Liebenberg - One of the best experts on this subject based on the ideXlab platform.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, S. L. Bud’ko, Terry M. Tritt, Paul C. Canfield, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, Terry M. Tritt, Paul C. Canfield, S. L. Bud’ko, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
A. L. Pope - One of the best experts on this subject based on the ideXlab platform.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, S. L. Bud’ko, Terry M. Tritt, Paul C. Canfield, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, Terry M. Tritt, Paul C. Canfield, S. L. Bud’ko, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
Paul C. Canfield - One of the best experts on this subject based on the ideXlab platform.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, S. L. Bud’ko, Terry M. Tritt, Paul C. Canfield, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, Terry M. Tritt, Paul C. Canfield, S. L. Bud’ko, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
Terry M. Tritt - One of the best experts on this subject based on the ideXlab platform.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, S. L. Bud’ko, Terry M. Tritt, Paul C. Canfield, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
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Thermal conductivity in large Residual Resistance ratio MgB2 wire
Journal of Applied Physics, 2003Co-Authors: A. L. Pope, Terry M. Tritt, Paul C. Canfield, S. L. Bud’ko, D. H. LiebenbergAbstract:We measured the thermal conductivity in MgB2 wires, with Tc=39.5 K, in both the superconducting and normal state regimes between 10–70 K. As expected, the thermal conductivity is increased for this sample, which has a Residual Resistance ratio (RRR) of about 32, as compared with earlier measurements on bulk samples with much lower RRR values. Over the measured temperature range, this more metallic material exhibits a temperature dependence of the thermal conductivity in the superconducting state that is different from that in previous reports and can be ascribed primarily to defect scattering. Unusual results are presented for the magnetic field dependence of the thermal conductivity around Tc for fields up to 9 T.
Teruo Matsushita - One of the best experts on this subject based on the ideXlab platform.
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Round Robin Test of Residual Resistance Ratio of Nb3Sn Composite Superconductors
IEEE Transactions on Applied Superconductivity, 2018Co-Authors: Teruo Matsushita, Taejong Hwang, Daniele Turrioni, Edmund Soji Otabe, L.d. Cooley, Michael John RaineAbstract:A round robin test of Residual Resistance ratio (RRR) was performed for Nb 3Sn composite superconductors prepared by internal tin method by six institutes with the international standard test method described in IEC 61788-4. It was found that uncertainty mainly resulted from determination of the cryogenic Resistance from the intersection of two straight lines drawn to fit the voltage vs. temperature curve around the resistive transition. As a result, the measurement clarified that RRR can be measured with expanded uncertainty not larger than 5% with the coverage factor 2 by using this test method.
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Round Robin Test of Residual Resistance Ratio of Nb3Sn Composite Superconductors
IEEE Transactions on Applied Superconductivity, 2018Co-Authors: Teruo Matsushita, Taejong Hwang, Daniele Turrioni, Lance Cooley, Michael John Raine, Edmund Soji Otabe, Damian P. HampshireAbstract:In this paper, a round robin test of Residual Resistance ratio (RRR) is performed for Nb3Sn composite superconductors prepared by an internal tin method by six institutes with the international standard test method described in IEC 61788-4. It was found that uncertainty mainly resulted from determination of the cryogenic Resistance from the intersection of two straight lines drawn to fit the voltage versus temperature curve around the resistive transition. The measurement clarified that RRR can be measured with expanded uncertainty not larger than 5% with the coverage factor 2 by using this test method.
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Residual Resistance Ratio Measurement Method of Cu/Nb3Sn Composite Conductors
Advances in Superconductivity XII, 2000Co-Authors: Satoru Murase, Takashi Saitoh, Hideki Moriai, Teruo Matsushita, Rikuo Ogawa, Kozo OsamuraAbstract:To submit Residual Resistance ratio (RRR) measurement method of Cu/Nb3Sn composite conductor as one of new work items to IEC-TC90 in the near future, inter-comparison tests have been carried out. Four laboratories joined the tests using the bronze-processed Cu/Nb3Sn with the external stabilizer as a sample. Laboratory W reacted and measured samples A, B and C, then they were distributed to the other three laboratories (X, Y and Z). Laboratories X, Y and Z measured samples A, B and C, respectively and those data were compared with those of W. As a result, coefficient of variation, COV, of RRR values of 6.7% was obtained. Thermoelectric voltages were also measured in the tests and it was found that it did not affect scattering of RRR measurement if we changed the polarity. If allowable target precision is extended up to around 10%, we will reach the goal of the standardization in RRR measurement method of Cu/Nb3Sn in a year.
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Inter-Comparison Test Results for Residual Resistance Ratio of Cu/Nb3Sn Composite Conductors
Advances in Superconductivity XI, 1999Co-Authors: Satoru Murase, Takashi Saitoh, Hideki Moriai, Teruo Matsushita, Kozo OsamuraAbstract:The Residual Resistance ratio (RRR) measurement method for Cu/Nb3Sn was selected to be one of the next new work proposal items for submission to IEC-TC90 in the near future. Inter-comparison tests have been carried out for some years in Japan and show that the RRR of Cu/Nb3Sn for the external Cu type is very sensitive to heat-treatment conditions and has large scattering. On the other hand, a relatively low scattering factor of under 9% was obtained in the test in which the scattering problems at heat-treatment were removed. If pre-reacted Cu/Nb3Sn is treated, the goal of the standardization in RRR measurement method will be attained before long.
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Results of Round Robin Test of Residual Resistance Ratio in Cu/Nb-Ti Composite Superconductor
Advances in Superconductivity XI, 1999Co-Authors: Teruo Matsushita, Satoru Murase, Edmund Soji Otabe, Kozo OsamuraAbstract:An international round robin test of the Residual Resistance ratio (RRR) measurement was carried out on a Cu/Nb-Ti composite superconductor following a Working Draft for the test method prepared by Working Group 4 in IEC/TC90. Thirteen institutes from five countries participated in the round robbin test. The effect of the bending strain on the Resistance at cryogenic temperatures was corrected using an empirical formula. The average and the standard deviation of RRR were 178.5 and 4.4, respectively. As a result the coefficient of variation (COV) was 2.44 %. Since the target of COV is 5 %, it is concluded that RRR can be correctly measured following the method in the Working Draft.
