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We report the magnetic field and temperature dependence of the critical current density {Jc(H) and Jc(T)} flowing in a 5 μm thick sample of SmBa2Cu3O7−δ (SmBCO) film. The film is a coated conductor (CC) deposited on an IBAD-MgO textured metallic template. For a range of intermediate fields, we find J c α H - α with values of α between 0.44 and 0.49. These values are lower than those reported for other CC in the literature. The sample has a Jc of 13.6 MA/cm2 at 5 K and self-field. Such high-Jc wires should find applications in large-scale energy applications of high-temperature superconductors. The temperature dependence of Jc at self-field and different applied fields is also analyzed.

Structural and transport properties of high performance SmBa2Cu3O7−x coated conductors produced by a dual-chamber co-evaporation are presented. The 5 μm-thick SmBCO coated conductors grown on IBAD-MgO based Hastelloy metal templates show critical currents larger than 1020–1560 A/cm at 77 K and self-field. The current transport characteristics of the conductors are investigated by room-temperature thermoelectric microscopy and low-temperature bolometric microscopy. The local thermoelectric images show the tilted grains, grain boundaries, and microstructural defects on the surface of the coated conductors. The bias current-dependent bolometric response at low temperature displays the current of the local flux flow dissipation as an increasing bias. Furthermore, we measured micro-Raman scattering microscopic imaging on oxygen-related peaks of the conductors. Comparing the Raman signal images with the low temperature optical scanning maps, it is remarkable that the structural disorders represented by oxygen-related Raman peaks are closely related to the low temperature bolometric abnormalities. From this result, a nature of the dissipative current distribution in coated conductors is revealed. The scanning optical microscopic study will provide a promising method for quality assurance of coated conductors.

The relationship between reproductive breast risk factors and breast cancer survival in patients with different breast cancer subtypes is not well known.We examined a large-sized, retrospective study of 23,882 subjects from the Korean Breast Cancer Registry. The breast cancer subtype was determined by immunohistochemical staining for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). Information regarding reproductive factors, including breastfeeding, age at first birth (AFB), and parity, was gathered. Multivariate Cox regression analysis was used to estimate the association among breast cancer subtypes, such as luminal A, luminal B, Her-2/neu overexpressing, and triple negative breast cancer (TNBC), and breast cancer survival as dependent variables and adjusting for age and stage.High parity (≥ 5) increased the recurrence risk of luminal A and B breast cancer (hazard ratio [HR], 1.95; 95% confidence interval [CI], 0.96-3.97; P = .0055 and HR, 1.12; 95% CI, 0.42-3.02, respectively; P = .0073) in breast cancer-specific survival (BCSS), but 1 to 3 child births decreased the recurrence risk of luminal A breast cancer (HR, 0.56; 95% CI, 0.34-0.91; P = .0055) and luminal B breast cancer (HR, 0.32; 95% CI, 0.17-0.61; P = .0073) in BCSS. Early AFB (20 years) increased the recurrence risk of luminal A breast cancers (HR, 1.61; 95% CI, 0.62-4.26; P = .039) in BCSS and of TNBC (HR, 1.31; 95% CI, 0.78-2.21; P = .0006) in overall survival. Her-2/neu overexpressing breast cancer had no correlation with parity and AFB in breast cancer survival.High parity (≥ 5) and early AFB (20 years) were correlated with worse clinical outcomes in patients with luminal breast cancer, but not with other subtyped breast cancers.

This paper reviews recent progress in research and development (R&D) of reactive co-evaporation for high performance REBCO coated conductors in Korea. Two types of reactive co-evaporation methods were developed for the deposition of SmBCO and GdBCO superconducting layers respectively on the IBAD (Ion Beam Assisted Deposition)-MgO template in the Korean coated conductor project. Batch type reactive co-evaporation equipment and its processing were developed for SmBCO coated conductors at Korea Electrotechnology Research Institute (KERI) in conjunction with the Korea Advanced Institute of Science and Technology (KAIST), and a very high critical current exceeding 1,000 A/cm at 77 K in the self field was achieved through the optimization of deposition parameters. Reel-to-reel type reactive co-evaporation processing with a high conversion rate was also developed, while long length GdBCO coated conductors have been routinely produced by SuNAM Co. The minimum critical current of 422 A/cm-w at 77 K in self field was confirmed for 1 km-long GdBCO tape.

In this study, the homogeneity of critical current, , along the lengthwise direction in the coated conductor (CC) tape under uniaxial tension was investigated using a multiple voltage tap configuration. Initially, a gradual and homogeneous degradation occurred in all subsections of the tape up to a certain strain value. This was followed by an abrupt degradation in some subsections, which caused scattering in values along the length with increasing tension strain. The degradation behaviour was also explained through n-value as well as microstructure analyses. Subsections showed scattering corresponding to damaged areas of the CC tape revealed that transverse cracks were distributed throughout the gauge length. This homogeneous degradation behaviour under tension is similar with the case under torsion strain but different with the case under hard bending which were previously reported. This behaviour is also different with the case using Bi-2223 HTS tapes under tension strain.

Sm 1+ x Ba 2− x Cu 3+ y O 7− δ (SmBCO) films were directly deposited on the epi-MgO/IBAD-MgO/Y 2 O 3 /Al 2 O 3 /Hastelloy template by co-evaporation using the evaporation using drum in dual chambers (EDDC) system without the buffer layer in order to investigate the effect of the composition ratios on superconducting property, microstructure and texture of SmBCO film. The films with gradient composition ratios of Sm:Ba:Cu were deposited using a shield with an opening which was placed between the substrate and the boats. The highest I c of 52 A (corresponding to J c = 1.6 MA/cm 2 and a thickness of 800 nm) was observed at 77 K in self field at a composition x = 0.01–0.05 and y = −0.23 to −0.46. When the composition ratio is outside this range, the I c value rapidly decreased. The superconducting critical current was highly dependent on the composition ratio. As the composition ratio is farther away from that of the highest I c , the SmBCO (1 0 3) peak intensity increased and the amount of a -axis oriented parts increased. A dense microstructure with round-shape grains was observed in the region showing the highest I c . The optimum composition ratio can be found by analyzing films deposited with variable deposition rates of each depositing element.

It was attempted to reproduce the measured critical current ( I c ) distributions of the Bi2223 composite tape bent by 0–0.833% by simulation. Simulation was carried out with a Monte Carlo method in combination with a model that correlates the critical current to damage evolution. Two variables that differ from specimen to specimen were input in the simulation. One was the damage strain parameter, with which the difference in extent of damage among specimens was expressed. Another was the original critical current ( I c 0 ) values at zero bending strain. With the present simulation approach, the measured distributions of critical current at various bending strains, and the measured variations of average and coefficient of variation of critical current values with increasing bending strain were reproduced well.

The magnetic properties of high T c superconductor (HTS) SmBa 2 Cu 3 O 7− δ (SmBCO) coated conductors (CCs) which are based on IBAD (ion-beam-assisted deposition) templates were investigated. The SmBCO CCs were fabricated on LaMnO 3 (LMO)/epi-MgO/IBAD-MgO/Hastelloy substrates by Evaporation using Drum in Dual Chamber (EDDC) processing. The measurements of isothermal magnetizations M ( H ) for the prepared SmBCO-CCs were carried out at various temperatures in magnetic fields up to 8.5 T. The magnetic properties for the applied magnetic fields parallel to the ab -plane show non-conventional behaviors when compared to those parallel to both c -axis and c -axis + 45°. These normal and anomalous properties can be explained by introducing the magnetic flux pinning effects related to the direction of the applied magnetic fields.

The magnetic properties of SmBa2Cu3O7-x (SmBCO) coated conductor (CC) that was fabricated on LaMnO3(LMO)/IBAD-MgO substrates using Evaporation using Drum in Dual Chamber (EDDC), which is a batch type co-evaporation system, was investigated. LMO buffer layer was deposited on IBAD-MgO templates by PLD method. The measurements of both the magnetization M(H) and the resistance R(T) for the SmBCO CC, were carried out at temperatures between 10 and 120 K in fields up to 8.5 T, using a PPMS-9T (with both ACMS and DCR options, Quantum Design). The SmBCO CC exhibited Tc (onset temperature) of 94.7 K with a narrow transition width of 0.6 K, which indicates a good homogeneity of the superconducting properties. The upper critical field Hc2 near Tc of the SmBCO CC has been estimated by the resistance R(T) approaches. The magnetization curves M(H) are symmetric about the line M = 0 for the SmBCO CC with the field applied parallel to both the c-axis and c-axis +45°. For the SmBCO CC with the field applied parallel to the ab-plane, they are asymmetric. These symmetric and asymmetric curves can be explained by introducing the bulk pinning of 1-D flux lines and surface barrier-dominated system of 2-D pancake vortices.

SmBa2Cu3O7 (SmBCO)-coated conductors were grown on IBAD-MgO templates by in-situ co-evaporation using a drum-in-dual-chambers system. The conductors, which had a coating thickness of up to 3 μm, showed a critical temperature of 92 ~ 94 K and a critical current of 150 ~ 625 A/cm-w at 77 K in a self-field. The phonon modes and cation disorder of the SmBCO-coated conductors were examined by polarized Raman scattering spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy. XRD showed (00l) peaks for the SmBCO phase. The Raman spectra revealed common vibration modes, including Ba-Ba stretching, Cu2-Cu2 stretching, O(2)+/O(3)-, and apical O(4) modes. In addition, polarized-Raman spectra were obtained to examine the crystal orientation and grain growth behavior. Structural information from the Raman spectra turned out to be useful to determine the optimal thickness of SmBCO-coated conductors with high critical currents.

In superconducting cable applications using the HTS tapes, striation of ReBCO coated conductor (CC) is being considered to reduce ac loss. The striation of ReBCO coating film with laser patterned filaments has been tried. In practical applications, the striated ReBCO CC tapes should also exhibit acceptable tolerance to mechanical stress/strains. However, reports on the electromechanical properties of striated CC tapes in bending or torsion mode are limited. In this study, the critical current degradation behavior of the striated Cu stabilized SmBCO CC tapes in pure torsion mode was investigated using a sample holder which gives torsional deformation to CC tapes. The CC tape has been laser scribed to produce multi-filaments. The Ic/Ic0 and n-value-torsional angle (θ) behaviors in the striated SmBCO CC tapes were examined and compared with the case of non-striated ones. According to the location of the coating film strip striated within the cross-section, there existed some difference in the Icf degradation behavior indicating that a non-uniform deformation was induced on each striated strip.

The (BHO) buffer layer on the IBAD MgO template was turned to be effective for a successful fabrication of (GdBCO) films with high critical current density (). Both the BHO buffer layers and GdBCO films were prepared by pulsed laser deposition (PLD). The effects of the PLD conditions, including substrate temperature (), oxygen partial pressure (), and deposition time on the in-plane texture, surface roughness, and microstructures of the BHO buffer layers on the IBAD MgO template were systematically studied for processing optimization. The c-axis oriented growth of BHO layers was insensitive to the deposition temperature and the film thickness, while the in-plane texture and surface roughness of those were improved with increasing from 700 to . On the optimally processed BHO buffer layer, the highest value (77 K, self-field) of 3.68 could be obtained from GdBCO film deposited at , representing that BHO is a strong candidate for the buffer layer on the IBAD MgO template.

We report a successful fabrication of c -axis oriented GdBa 2 Cu 3 O 7− δ (GdBCO) films on the BaSnO 3 (BSO) buffer layers on ion-beam assisted deposition (IBAD)-MgO template by pulsed-laser deposition (PLD). The (0 0 l ) growth and in-plane textures of BSO buffer layers were found sensitive to the substrate temperature ( T s ). With increasing the BSO layer thickness up to ∼165 nm, in-plane texture (Δ ϕ ∼ 6.2°) of BSO layers was almost unaltered while completely c -axis oriented BSO layers were obtainable from samples with the thickness below ∼45 nm. On the BSO buffer layers showing in-plane texture of 6.2° and RMS surface roughness of ∼8.6 nm, GdBCO films were deposited at 780–800 °C. All GdBCO films exhibited Δ ϕ values of 4.6–4.7°, T c,zero of ∼91 K, and critical current density ( J c ) over 1 MA/cm 2 at 77 K in a self-field. The highest J c value of 1.82 MA/cm 2 ( I c of 51 A/cm-width) was achieved from the GdBCO film deposited at T s of 790 °C. These results support that BSO can be a promising buffer layer on the IBAD-MgO template for obtaining high- J c GdBCO coated conductors.

When many multi-filamentary Bi2223 composite specimens with different irreversible bending strain to each other are tested, number of damaged specimens among all increases with bending strain in the low bending strain region near the average irreversible strain. The present work attempted to predict the distribution of critical current among many specimens in such a low bending strain region with a proposed simulation method that uses the damage evolution model, Monte Carlo method and the experimental data measured at limited strains. With the proposed simulation method, statistical features in variation of distribution of critical current values among specimens near the average irreversible bending strain were elucidated.

The influences of bending strain on the critical current, I c in stabilized YBa 2 Cu 3 O 7− δ (YBCO) and SmBCO coated conductor (CC) tapes in different modes of easy and hard bending were investigated at 77 K and self-field. Under easy bending, the influences of the compressive and tensile bending strains on the I c in REBCO (rare earth element, Barium and Copper oxide) CC tapes were investigated. Under tensile bending strain, when the I c was plotted against the strain on the YBCO film layer, the 95% I c retention strain limit under bending was comparable to the value obtained in the axial-tension test. Under the hard bending of YBCO CC tape, I c started to degrade when the bending strain exceeded 0.6% and the recovery of I c did not occur when the bending strain applied was released. This might be a result of the generation of a new type of damage such as local buckling during hard bending which is different from the damage type experienced in Bi-2223 tapes. The n -value behavior showed a good agreement with the I c degradation behavior. On the other hand, the SmBCO CC tape showed a superior strain tolerance under hard bending resulted from its flexibility to in-plane deformation due to thin geometry compared to other copper stabilized YBCO CC tapes.

The deposition conditions of LaMnO3 (LMO) buffer layer on Ion Beam Assisted Deposition (IBAD)-MgO template by reactive DC sputtering were investigated. We developed a specially designed chamber for reactive DC magnetron sputtering. The deposition chamber was composed of two sputtering guns with the mixed metallic target of La (50 at%) + Mn (50 at%), halogen lamp heater, QCM (Quartz Crystal Microbalance), RGA (Residual Gas Analyzer) and reel to reel tape moving system. We investigated the effect of oxygen flow rate on the deposition rate of LMO layer. We found that there was an optimal range of oxygen flow rate to have the desired layer. Above the range, the deposition rate decreased sharply and plasma was unstable. Below the range, the deposited layer was partially metallic. We investigated the effect of substrate temperature on the texturing of LMO layer. The texturing of LMO layer was improved by increasing the substrate temperature. We investigated the effect of deposition rate on the texturing of LMO layer. The LMO layer has a good texture in the deposition rate range of 0.07–0.21 nm/s. We confirmed that deposition rate had little effect on the texturing of LMO layer in the deposition rate range. Sm1Ba2Cu3O7−d superconducting layer was deposited on the LMO(reactive)/IBAD-MgO template. Ic and Jc were 81.6 A and 1 MA/cm2. This means that LMO layer deposited by reactive DC sputtering shows a good performance in superconductor coated conductor.

Using two different IBAD-MgO templates with the in-plane textures of ∼8.5° and ∼6.5° for MgO (2 2 0), respectively, we tried to identify the correlation between the LaMnO 3 (LMO) buffer layer and IBAD-MgO template and also to optimize the PLD processing conditions for the LMO layer. Better in-plane texture of the LMO buffer layer less than 7° was obtained from the IBAD-MgO template of ∼6.5° in-plane texture over almost all deposition temperature and time, supporting that the processing window is very wide, although the in-plane texture of LMO buffer layers was somewhat sensitive not only to deposition temperature but also to deposition time (or layer thickness). Optimally processed LMO buffer layer at deposition temperature of 775 °C in P O 2 of 100 mTorr for 10 min exhibited the Δ φ value of 5.2°.

It was attempted to estimate the Young’s modulus, thermally induced residual strain, intrinsic fracture strain and the coefficient of thermal expansion at room temperature of the Bi2212 filaments in Bi2212/Ag/Ag alloy composite wire by combining the results of tensile test, X-ray diffraction measurement and thermomechanical analysis. The Young’s modulus of the Bi2212 filaments was estimated to be 66.3 GPa from the analysis of the stress–strain curve of the composite. The thermally induced residual strain of Bi2212 filaments introduced during cooling due to the difference in thermal expansion among the constituents (Bi2212, Ag and Ag alloy) was estimated to be −0.14% by in situ synchrotron-radiation diffraction. The intrinsic fracture strain of Bi2212 filaments was 0.11–0.13% from the analysis of the stress–strain curve of the composite wire, in which the estimated residual strain was substituted. The coefficient of thermal expansion of the Bi2212 filaments was estimated to be 11.5 × 10−6 K−1 from the analysis of the thermal expansion of Bi2212 composite wire measured between 300 K and 400 K in combination with the property values estimated from the tensile test results.

Influences of bending strain on the critical current, Ic, in Cu-stabilized IBAD/EDDC processed SmBCO coated conductor (CC) tapes were investigated at 77 K and self-field using a small-scale Goldacker type bending test rig. Considering the location of the superconducting layer against the neutral axis, tensile and compressive bending strains were applied to the SmBCO coating layer and the strain effect on Ic degradation was discussed. Under tensile bending strain, the Ic decreased monotonically but recovered reversibly up to the irreversible strain limit. Under compressive bending strain, however, the Ic increased but in some cases it suddenly dropped after straightening due to the delamination of the copper stabilizer. Also, repeated bending strains were applied to Cu-stabilized SmBCO CC samples in order to observe the behavior of Ic under cyclic loading. Ic Initially decreased with the application of 0.7% bending strain, but when the tape was subjected to repeated bending up to 100 cycles, no more degradation occurred. And finally, the Ic almost recovered to Ic0 when the tape was straightened.

Effect of filament configuration and heat treatment of Bi2212/Ag round wire with low Ag ratio on the engineering critical current density (Je) was reported. We have fabricated 557, 85 7, and 121 7 wires with different Ag ratio and evaluated at various wire diameters. We have also changed the parameters of heat treatment. The effects of maximum process temperature (Tmax)and soaking time at Tmax and average filament diameter on the Je were also studied. 121 7 wire of 0.95 mm diameter heat-treated at showed Je of 858mm2 at 4.2K, 0 T.

The goal of this study was to develop a novel cooking method for fried meat products, to improve their nutritional value, and to provide superior taste and texture. We used the fat derived from each individual meat source during radiant heat roasting (alternate roasting with its own fat: AROF) without deep-fat frying (DFF), first without any air flow and subsequently with an exposure to air flow. We then compared these roasted chicken samples to breaded fried chicken samples that were deep-fat fried in 3 types of fat: soybean oil (SB), partially hydrogenated soybean oil (PSB), and lard. The final fat contents of both the skin and lean parts of the AROF samples of chicken were less than half of those of the DFF groups. The total trans-fatty acids (TFA) contents were significantly lower in the AROF samples compared to the DFF samples. The cholesterol levels of the samples did not show any significant differences among the tested groups, except for the sample fried in lard, which was significantly higher. Moreover, the sensory evaluation results showed that the crispy texture of the AROF samples was not significantly different from that of the DFF samples (P < 0.05); the AROF samples had higher scores for the characteristic fried flavor and for overall acceptability (P < 0.05). This study shows the potential value of products prepared by AROF, which can successfully replace DFF methods used for chicken and other meat products and improve their nutritional value.

To examine the effect of solvent treatments on the superconducting properties of MgB 2 , solvent-treated MgB 2 powders were prepared by mixing with water, acetone, or ethanol. No degradation of the superconductivity of MgB 2 by the acetone or ethanol treatments was observed. Appreciable change which accompanies degradation of superconducting properties was observed only when MgB 2 was mixed with water. In addition, to investigate the variation of the flux pinning effect due to the aging, the Ag 8 –MgB 2 , (SiC) 4 –MgB 2 , and sintered pure-MgB 2 pellets were kept at room temperature for two and half years in air. The aged Ag 8 –MgB 2 composite superconductor has showed degradation of flux pinning effect. The in-field superconducting properties of (SiC) 4 –MgB 2 , however, did not change after aging.

We have fabricated SmBCO coated conductor on IBAD-MgO substrates using unique co-evaporation method. The batch type co-deposition system was specially designed and was named EDDC (evaporation using drum in dual chamber) that is possible to deposit superconducting layer with optimum composition ratio of materials at temperature over 700 °C and several mTorr of oxygen. In this study, we have investigated the influence of SmBCO phase composition ratio on the critical current density of coated conductor. We have optimized the composition ratio by changing the deposition rates of Ba and Cu during co-evaporation for better critical current density. A higher critical current density was measured at the composition ratio of Ba deficiency (1.9–2.0) and Cu rich (3.2–3.4) compared to the Sm 1 Ba 2 Cu 3 O y stoichiometry. Especially, highest critical current density of 2.6 MA/cm 2 was measured at the composition of Sm 1 Ba 1.9 Cu 3.2 O y that has dense surface morphology.

SrRuO 3 thin films have been grown in situ on single crystal LaAlO 3 substrates and textured metal templates which contain an MgO layer produced by an ion-beam growth method. Deposition was made of oxygen partial pressure in a range from 50 m Torr to 250 m Torr with laser repetition rate of 5 Hz. Substrate temperature was between 600 °C and 800 °C. Dependence of out-of-plane and in-plane orientation of SrRuO 3 thin films on pressure and growth temperature was investigated by X-ray diffraction. The surface morphology and grain growth behaviors of SrRuO 3 thin films were analyzed by atomic force microscopy and scanning electron microscopy. In addition, the transverse magnetoresistance value in a field of 4 and 8 T was measured in temperature range of 50–200 K and the ferromagnetic transition at ∼140 K of SrRuO 3 films on LaAlO 3 was detected by resistivity measurement.

The tensile strain dependence of the critical current, I c , in two kinds of commercially available YBCO coated conductors (CC) and another one fabricated at KERI, which were processed by using the rolling-assisted biaxially textured substrates (RABiTS) and the ion-beam assisted deposition (IBAD) techniques, have been investigated. The mechanical properties including the Young’s modulus and 0.2% offset yield stress at 77 K have been derived. The IBAD-processed samples showed a higher yield stress than the RABiTS/MOD processed one. Also, the irreversible strain/stress limits of I c have been investigated at 77 K and self-field. The influence of stabilizer on the I c degradation behavior in YBCO CC tapes with IBAD substrates was discussed. The irreversible strain limits defined by unloading could be explained well by the variation in the n -value-strain relation.

Highly textured long-length MgO template was successfully deposited on a polycrystalline metal tape using ion-beam-assisted deposition (IBAD). To increase the speed of the IBAD processing, tape moving system was modified from a single-turn to multi-turn system with 14-pass and five heating zones, which leads to larger deposition area. The overall process consists of reel-to-reel electro-polishing of a Hastelloy C276 tape, deposition of Al 2 O 3 diffusion layer and Y 2 O 3 seed layer, deposition of IBAD*-MgO and homo-epi MgO layer, and deposition of LaMnO 3 (LMO) buffer layer and YBa 2 Cu 3 O 7-δ (YBCO) superconducting layer using pulsed laser deposition (PLD). Recently, 100 m long IBAD-MgO tape with in-plane texture of Δ∅ < 7° has been successfully fabricated. Critical current density (J c ) of 0.94 MA/cm 2 at 77 K in self field was obtained from the YBCO coated conductor grown on 20 cm long LMO-buffered IBAD-MgO template by the PLD process.

Round shape Bi2212/Ag wire is isotropic, while Bi2212/Ag or Bi2223/Ag tape has anisotropic characteristics or performances with respect to magnetic field orientation, which is the only HTS wires that can be used to make Rutherford cable to transport high current. In this work, two different Bi2212/Ag round wires with different Ag ratio were fabricated using powder-in-tube method and processing factor at each step was investigated. Double stacked 385 (55 × 7) filamentary wires of various final diameter were heat treated at different melting temperatures. Microstructure after pre-annealing was investigated. Wires which have Ag ratio (silver area/superconductor area) of 0.3 and 0.42 after powder filling show similar critical current density. Higher Ag ratio wire at 0.74 mm diameter heat treated at melting temperature 890 °C shows critical current density of 2750 A/mm2 at 4.2 K, 0 T.