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Abstract: This paper describes stability of CICC superconducting magnets related with RRL (Ramp-Rate Limitations). Although RRL is known as a significant obstacle for successful operation of field-varying AC superconducting magnets, its precise investigation is difficult due to complex unknown parameters and difficulties of experimental measurements. To investigate RRL for practical multi-strand CICC, a simplified analysis model is suggested with some reasonable assumptions. This model considers accurate current diffusion phenomenon inside CICC and realistic transient convection heat transfer by supercritical helium. Parametric study is also performed with the analysis model to investigate the effect of the strand parameters. Summarizing the quench recovery or cable quench result after a local quench for given simulation parameters, a new stability evaluation method is suggested and it can give some design criterion by guaranteeing the stable operation regime of superconducting magnets. The new evaluation method, which is called ‘RRL quench recovery map’, is applied to the previous experimental results and it shows that this map can be used as a design criterion for practical superconducting magnets. [Copyright &y& Elsevier]

Ramp-rate limitation, which is known as a serious obstacle for fast charging of a superconducting magnet, is investigated by an experiment with a two-strand sample conductor and numerical analysis. During the experiment, typical ramp-rate limitation results were observed. The sample showed quench recovery by current redistribution or irreversible `cable quench' according to the operation conditions. To investigate the recovery or quench criterion, numerical analysis is performed considering both electro-magnetic and thermal interaction. The simulation results show that the status of the low-current strands determines `recovery' or `cable quench' when the `local quench' first occurs at the high-current strand. From the analysis, heat transfer conditions such as boiling heat transfer and contact heat transfer between the strands as well as current nonuniformity are the most governing factors for the stability criterion. Therefore, it is possible to propose a stability criterion for the ramp-rate limitation according to the operation condition of the superconducting magnet. Moreover, the effect of heat transfer conditions to overcome the ramp-rate limitation for the given operation conditions is investigated quantitatively. [ABSTRACT FROM AUTHOR]

Describes an experimental apparatus and measurement results of the individual cable-in-conduit conductor (CICC) magnet constructed at the Korea Advanced Institute of Science and Technology in Taejon. Unbalanced current distribution from the shunt resistor voltage date; Current redistribution inside the conduit due to minimal surface contact resistance of the superconducting strands.

Although safflower seed extract exhibits pharmacological activity against various diseases, the effects of its individual compounds on osteoarthritis (OA) have not been elucidated. Here, we evaluated the effects of these extracts and their single compounds on OA. N-(p-Coumaroyl) serotonin and N-feruloyl serotonin, main components of safflower seed extract, were isolated by high-performance liquid chromatography. Under in vitro OA mimic conditions, the expression of the matrix metalloproteinases (MMPs) MMP3/13 and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) ADAMTS5 were reduced in mouse chondrocytes treated with safflower seed extract. Furthermore, the oral administration of safflower seed extract attenuated cartilage destruction in a mouse OA model induced by destabilization of the medial meniscus. N-(p-Coumaroyl) serotonin and N-feruloyl serotonin, but not serotonin, reduced MMP3, MMP13, and ADAMTS5 expression in IL-1β-treated chondrocytes. Additionally, they significantly blocked the nuclear factor-κB (NF-κB) pathway by inhibiting IκB degradation and p65 phosphorylation. Our results suggest that safflower seed extract and its single compounds can attenuate cartilage destruction by suppressing MMP and ADMATS5 expression. The anti-arthritic effects are mediated by NF-κB signaling and involve the inhibition of IκB degradation and p65 phosphorylation. These results indicate that safflower seed extract may serve as a novel therapeutic agent against OA. [ABSTRACT FROM AUTHOR]

The ITER facility is an international research project that is under construction in Cadarache, France. US ITER is responsible for the design, engineering, and procurement of the Tokamak Cooling Water System (TCWS). TCWS piping size varies from DN40 to DN500. A design guideline specifies that piping smaller than DN150 must have a fluid velocity below 6 m/s, while a fluid velocity of up to 9 m/s is permitted for piping larger than DN150. Fluid velocity affects pipe size, pressure drop, pump size, piping support, etc. Factors considered when determining maximum allowable fluid velocity include erosion and corrosion, pump capacity, cavitation, hydrodynamic instability, and actual nuclear plant experience. The previous study performed to support the ITER piping design indicated that the hydrodynamic instability was a reason to limit maximum allowable fluid velocity below 6 m/s regardless of the piping size. However, the later study found that, when properly supported, pipe buckling and fluttering from hydrodynamic force would not cause instability. Instead, cavitation erosion—a pipeline phenomenon that forms vapor cavities in pipe—may limit allowable fluid velocity. Cavitation is a pipeline phenomenon that forms vapor cavities, which then go unstable and collapse violently in low-pressure, turbulent, flow-separation regions inside valves, elbows, pipe expansions, and other fluid handling components. Considering the cavitation issue, pressure drop, and a typical practice in a nuclear plant system, fluid velocity is to limit below 6 m/s for piping smaller than DN150 and 9 m/s for piping larger than DN150. This paper describes a hydraulic stability analysis, the fluid velocity generally accepted in nuclear plants and the cavitation-erosion limit in fluid velocity. [ABSTRACT FROM AUTHOR]

Parallel flow heat exchangers with manifolds are widely used in various industries owing to their compact size and ease of application. Research has been conducted to understand their flow characteristics and improve flow distribution and pressure drop performance; however, it is difficult to derive generalized improvements under different conditions for each application. This study proposes a novel design to improve the flow characteristics of a compact heat exchanger with a sudden expansion area of a dividing manifold and uses computational fluid dynamics simulation to verify it. The abrupt cross-sectional area change in the dividing manifold induces a jet flow near the entry region, which causes the flow maldistribution of the first few parallel tubes. To improve the efficiency of the dividing manifold, simple and novel designs with a converging-diverging area in the manifold header have been proposed. Parametric studies on the novel designs show improvements of up to 37.5% and 52.0% flow uniformity and 2.65% and 0.74% pressure drop performance for U- and Z-types, respectively, compared to the base model. Thus, the simple and easily fabricated quadrilateral shape can improve the flow maldistribution and pressure drop caused by a dividing manifold with a sudden area expansion. [ABSTRACT FROM AUTHOR]

Lightweight reactor materials that simultaneously possess low heat capacity and large surface area are desirable for various applications such as catalytic supports, heat exchangers, and biological scaffolds. However, they are challenging to satisfy this criterion originating from their structural property in most porous cellular solids. Microlattices have great potential to resolve this issue in directing transport phenomena because of their hierarchically ordered design and controllable geometrical features such as porosity, specific surface, and tortuosity. In this study, we report hollow ceramic microlattices comprising a 10 μm thick hollow nickel oxide beam in an octet-truss architecture with low heat capacity and high specific surface area. Our microarchitected reactors exhibited a low heat capacity for a rapid thermal response with a small Biot number (Bi << 1) and large intertwined surface area for homogeneous flow mixing and chemical reactions, which made them ideal candidates for various energy applications. The hollow ceramic microlattice was fabricated by digital light three-dimensional (3D) printing, composite electroless plating, polymer removal, and subsequent thermal annealing. The transient thermal response and fluidic properties of the 3D-printed microstructures were experimentally investigated using a small-scale thermal and fluid test system, and analytically interpreted using simplified models. Our findings indicate that hollow microarchitected reactors provide a promising platform for developing multifunctional materials for thermal and fluid applications. [ABSTRACT FROM AUTHOR]

A complete understanding of single electron behavior in mesoscopic conjugated polymers is necessary for the development of advanced organic light emitting diodes, spintronics, flexible electronics and bioelectronics. In this study, we investigate the charge dynamics of conjugated polymer nanowires (CPNWs), synthesized using polypyrrole (PPy) and poly (3, 4- ethylenedioxythiophene) (PEDOT) and having diameters of 100 and 200 nm. The electrical properties and magnetic behavior of charges at the localized doping sites are probed using temperature dependent I–V analysis and electron paramagnetic resonance (EPR) spectroscopy. The I–V curves indicate that the applied bias and the diameter of the CPNWs, as well as their crystallinity, are important factors for charge injection and transport along the polymer chain. The EPR experiments show a relative increase in the spin relaxation time of PPy whereas a corresponding decrease is observed for PEDOT, as the diameter decreases. Based on the experimental results, the size effect and the interaction between charge carriers within the one-dimensional conducting polymer are discussed considering the doping states. These results are expected to extend the understanding of electronic behaviors in mesoscopic conjugated polymers. Image 1 • Two sized crystalline conjugated polymer nanowires (CPNWs) were synthesized. • Temperature dependent dc conductivity is analyzed by 3-D variable range hopping model. • Electron paramagnetic resonance shows that polaron is dominant charge carrier in CPNWs. [ABSTRACT FROM AUTHOR]

This study was conducted to identify the composition and diversity of the microbiome in tissues of pancreatic cancer and to determine its role. First, extracellular vesicles (EVs) were obtained from the paired tumor and normal tissues, and 16s rRNA gene sequencing was performed. We identified the microbiomes, compared the diversity between groups, and found that Tepidimonas was more abundant in tumors. Second, larger tumors resulted in lower levels of Leuconostoc and Sutterella, and increased lymph node metastasis resulted in higher levels of Comamonas and Turicibacter in tumor tissues. Moreover, in the case of tumor recurrence, the levels of Streptococcus and Akkermansia were decreased in tumor tissues. Finally, with the supernatant of Tepidimonasfonticaldi, proliferation and migration of cells increased, and epithelial-mesenchymal transition and the Tricarboxylic Acid (TCA) cycle-related metabolites were enhanced. The composition and diversity of EV-derived microbiomes are important for providing novel insights into theragnostic approaches in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Various high-temperature superconducting (HTS) power cables are being developed or are ready for commercial operation to help energy suppliers meet the growing power demand in urban areas. Recently, triaxial HTS power cables have been developed by Korea Electric Power Corporation (KEPCO) and LS Cable & System. Further, KEPCO has been planning to install a 2 km long 23 kV/60 MVA triaxial HTS power cable to connect the Munsan and Seonyu substations and increase the stability of the power grid. The HTS power cables should be cooled down to a cryogenic temperature near 77 K. A thermo-hydraulic analysis of the cooling system considering the geographical characteristics of the installation site is essential for long-distance sections. This paper describes the thermo-hydraulic analysis of the triaxial HTS power cable to determine the proper mass flow rates of subcooled liquid nitrogen that meet the operating temperature and pressure of the cable for four configurations of cooling systems: (1) a single cooling system with an external return path, (2) a dual cooling system with an external return path, (3) a single cooling system with an internal return path, and (4) a dual cooling system with internal return path. Since the flow characteristics in a corrugated cable cryostat differ significantly from those in a typical annular tube, a computational fluid dynamics (CFD) analysis was conducted to estimate the pressure drop along the cable cryostat. With the CFD analysis and given heat loads in the cable, the temperature and the pressure variations along the cable were calculated and their pros and cons were compared for each configuration of the cooling system. This thermo-hydraulic analysis will be referenced in the actual installation of the HTS power cable between the Munsan and Seonyu substations. [ABSTRACT FROM AUTHOR]

Infrared detectors on satellites and spacecraft require cooling to increase their measurement sensitivity. To efficiently cool infrared detectors in a zero gravity environment and in limited spaces, a cryogenic loop heat pipe (CLHP) can be used to transfer heat over a certain distance by the capillary forces generated from porous wicks without a mechanical power source. The CLHP presented in this study transfers the heat load to a condenser 0.5 m away from an evaporator at temperatures below −150 °C. The CLHP with two evaporators includes a subloop for initial start-up, and uses a pressure reduction reservoir (PRR) for the supercritical start-up from room to cryogenic temperature. Nitrogen is used as the working fluid to verify the thermal behavior of the CLHP, and the heat-transfer capacity according to the nitrogen charging pressure of the PRR is investigated. To simulate a cryogenic environment, the CLHP is installed inside a space environment simulator, including a single-stage GM (Gifford McMahon) cryocooler to cool the condenser. The CLHP is horizontally installed to simulate zero gravity. The heat-transfer characteristics are experimentally evaluated through the loop circulation of the CLHP. [ABSTRACT FROM AUTHOR]

Herein, we reported on the precise growth and optical waveguide characteristics of hexagonal tris(8-hydroxyquinoline)aluminum(Ⅲ) (Alq3) micro-crystals (MCs). The hexagonal Alq3 MCs were prepared using surfactant-assisted assembly growth with the help of cetyltrimethylammoniumbromide (CTAB), in which the crystallization occurred as a result of molecular assembly and packing. Also, we adjusted the molar ratio of Alq3 and CTAB for the control degree of crystallization. The formation and structure of Alq3 MCs were investigated using field-emission scanning electron microscopy and X-ray diffraction pattern experiments, respectively. The solid-state laser confocal microscope-photoluminescence spectra and charge-coupled device images for the Alq3 MCs were measured to study the luminescence efficiency and colors, respectively. The optical waveguide performance of the hexagonal Alq3 MCs was measured for each side direction. According to our results, crystalline Alq3 micro-crystals are promising materials for application to the development of optical communication devices. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate the simultaneous enhancement of Raman and photoluminescence (PL) of core-shell hybrid nanoparticles consisting of Ag (core) and polydiacetylene (PDA, shell) through the assistance of localized surface plasmon (LSP) effect for the effective biosensor. Core-shell nanoparticles (NPs) are fabricated in deionized water through a sequential process of reprecipitation and self-assembly. The Raman signal of PDA on core-shell NPs is enhanced more than 100 times. Also, highly enhanced photoluminescence is observed on Ag/PDA hybrid NPs after coupling of the complementary t-DNA with p-DNA which are immobilized on PDA shell. This indicates that the core Ag affects the Raman and PL of PDA through the LSP resonance, which can be caused by the energy and/or charge transfer caused by the LSP coupling and the strong electromagnetic field near Ag NP surface. Only electrons present on the surface interact with the PDA shell, not involving the electrically neutral part of the electrons inside the Ag NP. Furthermore, this work shows that as prepared Ag/PDA NPs functionalized by probe DNA can sense the target DNA with an attomolar concentration (100 attomole). [ABSTRACT FROM AUTHOR]

Yes-associated protein (YAP)-1 is highly upregulated in pancreatic cancer and associated with tumor progression. However, little is known about the role of YAP1 and related genes in pancreatic cancer. Here, we identified target genes regulated by YAP1 and explored their role in pancreatic cancer progression and the related clinical implications. Analysis of different pancreatic cancer databases showed that Neuromedin U (NMU) expression was positively correlated with YAP1 expression in the tumor group. The Cancer Genome Atlas data indicated that high YAP1 and NMU expression levels were associated with poor mean and overall survival. YAP1 overexpression induced NMU expression and transcription and promoted cell motility in vitro and tumor metastasis in vivo via upregulation of epithelial–mesenchymal transition (EMT), whereas specific inhibition of NMU in cells stably expressing YAP1 had the opposite effect in vitro and in vivo. To define this functional association, we identified a transcriptional enhanced associate domain (TEAD) binding site in the NMU promoter and demonstrated that YAP1–TEAD binding upstream of the NMU gene regulated its transcription. These results indicate that the identified positive correlation between YAP1 and NMU is a potential novel drug target and biomarker in metastatic pancreatic cancer. [ABSTRACT FROM AUTHOR]

We fabricated hybrid nanoparticles consisting of organic semiconducting material with peptide sequence to reflect the target protein interaction. A phosphorescent OLED material, platinum octaethylporphyrin (PtOEP) was self-assembled by reprecipitation with the A17 peptide (YCAYYSPRHKTTF) selected as a probe ligand in order to recognize heat shock protein 70 (HSP70). The phosphorescence intensity of the PtOEP-A17 assembly was enhanced by 125 % after treatment with HSP70. The specificity of the protein interaction was confirmed in both solution and solid states of the PtOEP-A17 assembly against to BSA and nucleolin. We figured out that the phosphorescence lifetime of PtOEP-A17 assembly after exposed to HSP70 increased significantly to 153 ns from initial 115 ns. These simultaneous enhancements in phosphorescence and lifetime triggered by the specific protein interaction would open new applications of PtOEP, a representative material of light-emitting device fields. [Display omitted] [ABSTRACT FROM AUTHOR]

The original version of this Article contained errors in Figs. 4, 5, and 6. In Fig. 4d, the x-axis label incorrectly read ‘blank, +, blank, +’, and in Fig. 5e, the bars of the second graph from the left were coloured blue-orange-blue-orange. Both of these errors have been fixed in the PDF and HTML versions of the Article. Furthermore, in Fig. 6a, the right-hand image of AGS cells treated with 5 µM DY131 was inadvertently replaced with a duplicate of the left-hand image. The correct version of this figure panel appears in the Author Correction associated with this Article. For transparency, the error has not been corrected in the PDF or HTML versions of the Article. [ABSTRACT FROM AUTHOR]

Pancreatic adenocarcinoma upregulated factor (PAUF) is a ligand of toll-like receptors (TLRs) and has been reported to be involved in pancreatic tumor development. However, the significance of PAUF expression in epithelial ovarian cancer remains unclear. We aimed to investigate the possible clinical significance of PAUF in epithelial ovarian cancer. We examined the link between PAUF and TLR4 in ovarian cancer cell lines. Recombinant PAUF induced cell activation and proliferation in ovarian cancer cell lines, whereas PAUF knockdown inhibited these properties. Subsequently, we assessed PAUF and TLR4 expression by immunohistochemistry on tissue microarray of 408 ovarian samples ranging from normal to metastatic. PAUF expression positively correlated with TLR4 expression. Overexpression of PAUF was associated with high-grade tumor (p = 0.014) and chemoresistant tumor (p = 0.017). Similarly, high expression of TLR4 correlated with advanced tumor stage (p = 0.002) and chemoresistant tumor (p = 0.001). Multivariate analysis indicated that PAUFhigh, TLR4high, and PAUFhigh/TLR4high expression are independent prognostic factor for progression-free survival, while TLR4high and PAUFhigh/TLR4high expression were independent prognostic factors for overall survival. Our results suggest that PAUF has a role in ovarian cancer progression and is a potential prognostic marker and novel chemotherapeutic target for ovarian cancer. [ABSTRACT FROM AUTHOR]

In this study, an artificial neural network (ANN) model was applied to predict the thermo-hydraulic performance of the offset-strip fin heat exchanger. The ANN model was used for predicting the thermo-hydraulic performance to improve the prediction accuracy and extend the applicable range compared to the results of using the empirical equations reported in previous studies. The main parameters of these empirical equations were fin height (0.134 < α < 0.997), fin length (0.012 < δ < 0.048), fin width (0.041 < γ < 0.121), and Reynolds number (120 < Re <104). In addition, the Fanning friction factor f and the Colburn factor j were considered as the outputs of the ANN model. The impact of the parameters on the thermo-hydraulic performance of the heat exchanger was quantitatively evaluated, and the prediction accuracy was improved over a wide range for the thermo-hydraulic performance generated by the ANN model. Thus, the results obtained using the ANN model agreed well with the experimental data over a wider range than possible for the previous empirical correlations, showing extremely high accuracy and validity of the ANN model in comparison to the empirical equations. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a chronic inflammatory skin disease that results from eczema, itching, disrupted barrier function and aberrant cutaneous immune responses. The aim of the present study was to assess the efficacy of kushenol F as an effective treatment for AD via the suppression of thymic stromal lymphopoietin (TSLP) production. The results of the present study demonstrated that the clinical symptoms of AD were less severe and there was reduced ear thickening and scratching behavior in kushenol F-treated Dermatophagoides farinae extract (DFE)/1-chloro-2,4-dinitrochlorobenzene (DNCB)-induced AD mice. Histopathological analysis demonstrated that kushenol F decreased the DFE/DNCB-induced infiltration of eosinophil and mast cells and TSLP protein expression levels. Furthermore, kushenol F-treated mice exhibited significantly lower concentrations of serum histamine, IgE and IgG2a compared with the DFE/DNCB-induced control mice. Kushenol F also significantly decreased phosphorylated NF-κB and IKK levels and the mRNA expression levels of IL-1β and IL-6 in cytokine combination-induced human keratinocytes. The results of the present study suggested that kushenol F may be a potential therapeutic candidate for the treatment of AD via reducing TSLP levels. [ABSTRACT FROM AUTHOR]

Primary cilia start forming within the G1 phase of the cell cycle and continue to grow as cells exit the cell cycle (G0). They start resorbing when cells re-enter the cell cycle (S phase) and are practically invisible in mitosis. The mechanisms by which cilium biogenesis and disassembly are coupled to the cell cycle are complex and not well understood. We previously identified the centrosomal phosphoprotein NDE1 as a negative regulator of ciliary length and showed that its levels inversely correlate with ciliogenesis. Here, we identify the tumor suppressor FBW7 (also known as FBXW7, CDC4, AGO, or SEL-10) as the E3 ligase that mediates the destruction of NDE1 upon entry into G1. CDK5, a kinase active in G1/G0, primes NDE1 for FBW7-mediated recognition. Cells depleted of FBW7 or CDK5 show enhanced levels of NDE1 and a reduction in ciliary length, which is corrected in cells depleted of both FBW7 or CDK5 and NDE1. These data show that cell cycle-dependent mechanisms can control ciliary length through a CDK5- FBW7- NDE1 pathway. [ABSTRACT FROM AUTHOR]

This study analyzes the quench behavior of No-insulation (NI) REBCO pancake. An quench analysis simulation model considering the complex critical current density distribution was developed and validated experimentally. The developed model includes an equivalent circuit model, a thermal model, a magnetic model, and a magnet critical current estimation model. The simulation model is based on a co-simulation using MATLAB and COMSOL, considering the balance of accuracy and computation time. The lumped parameter of the NI magnet was used to solve the governing equations of the equivalent circuit module and thermal module in MATLAB. To accurately calculate the non-uniform electromagnetic field distribution over the coil, a magnetic finite element method was used in COMSOL. A neural network was used to predict the temperature-field-angle dependent magnet critical current. Considering the numerical convergence at different over-current phases, adaptive simulation was used to reduce the total simulation time. The quench behavior was analyzed using the proposed model, and the results were verified experimentally. The simulation results showed that when the azimuthal current is greater than the magnet critical current, it will gradually saturate and approach the magnet critical current, and then decrease at a similar speed. The rate of decrease is equal to the rate of decrease of the magnet critical current. Through the analyses, the corresponding sudden-discharging behavior was simulated and analyzed. The proposed model can be used to perform the post-quench and sudden discharging analyses of pancake coil and has promising applications in multi-pancake post-quench studies. [ABSTRACT FROM AUTHOR]

For the conduction cooling application, epoxy impregnation is inevitable to enhance the thermal conduction. However, there have been several research results on the delamination problem with coated conductor and the main cause of the delamination is related with the different thermal contraction between epoxy, the insulation layer and the weak conductor. To avoid this problem, the amount of epoxy and insulation layer between conductors should be minimized or removed. Therefore, no insulation (NI) winding method and impregnation after dry winding can be considered to solve the problem. The NI coil winding method is very attractive due to high mechanical/thermal stability for the special purpose of DC magnets by removing the insulation layer. In this paper, the NI coil winding method and vacuum impregnation are applied to a HTS coil to avoid the delamination problem and enhance the mechanical/thermal stability for the conduction cooling application. Through the charging/discharging operation, electric/thermal characteristics are investigated at 77 K and 30 K. [ABSTRACT FROM AUTHOR]

• The feasibility of the CLHP as a cryogenic heat switch was experimentally validated. • The switching-off process of the CLHP heat switch was investigated. • The effects of some parameters governing the on/off thermal conductance ratio of the CLHP heat switch were studied. The nitrogen-charged cryogenic loop heat pipe (CLHP) was utilized as an effective cryogenic heat switch operating at around 100 K by thermally connecting or blocking a cryogenic heat source and a cryogenic heat sink. The switching-off function of the CLHP heat switch was achieved by eliminating heat load on the secondary evaporator without any dedicated support of additional components or mechanisms during a normal operation. The removal of heat load on the secondary evaporator leads to the dry-out of the primary evaporator, which causes the thermal switching-off ultimately. The on/off thermal conductance ratios of the CLHP heat switch were obtained in various operational conditions such as different heat loads on the primary and secondary evaporators and different initial charging-pressures of nitrogen. The switching-off process divided into the on-state, transient state, and off-state was investigated experimentally, and the characteristics in the unsteady off-state were specially analyzed in detail. The obtained on/off thermal conductance ratios of the CLHP heat switch were in the range from 400 to 3900 in the experiments which are exceedingly larger than those of the conventional heat switches. The ratio becomes larger when the initial charging-pressure of working fluid is low but the heat loads on the primary evaporator and/or the secondary evaporator are large because the effective thermal conductance in the on-state is dominantly affected by the mass flow rate of working fluid. Between the heat loads on the primary and secondary evaporators, the on/off thermal conductance ratio of the CLHP heat switch is more sensitively affected by the heat load on the PE. [ABSTRACT FROM AUTHOR]

In this paper, we describe a cooling system for a high temperature superconducting (HTS) magnet of 10 MW class superconducting wind power generator (SWPG). To cool the HTS magnet below 35 K, a novel neon-helium hybrid cooling system is proposed. Neon cools the heat exchanger based on the thermosiphon principle and a cryogenic blower forcibly circulates helium gas between the heat exchanger, attached to a rotating neon vessel, and the HTS magnets. This cooling system has two advantages: applicability to large rotating HTS magnets and high reliability by removing a cryogenic or a high-pressure rotating coupling. To verify the performance of this cooling system, a lab-scale performance evaluation system(PES) is designed. The PES will be proved by cooling the generated heat and penetrated heat of the HTS magnets during operation. This paper describes the detail design process and the preliminary test results of the fabricated cooling system. [ABSTRACT FROM AUTHOR]

No-insulation (NI) winding techniques are widely used in fabricating thermally, mechanically, and electrically robust REBCO magnets. However, NI coils have disadvantages during charging operation, such as charging delay and heat loss due to leakage current. Leakage current can be reduced by increasing contact resistance. Metal-insulation (MI) winding methods are also used by co-winding high-resistive metal insulators between the winding turns of REBCO wires. Although the contact resistance of MI coils can be substantially increased, quantitative estimation of the magnet contact resistance is difficult owing to the dry-contact between the winding turns. Moreover, special care is needed during epoxy impregnation of MI or NI magnets owing to delamination problems induced by the epoxy layer between the winding turns. In this study, a soldered metal insulation (SMI) method is proposed to remove the drawbacks of the MI coil, such as the hardly predictable contact resistance and the delamination issue during conduction cooling applications. The SMI coils were wound using a tin-plated stainless-steel (SS) tape between the REBCO wires as in the MI coil and they were heated in a furnace to produce soldered contacts between winding turns. To investigate the electric characteristics, sudden discharge and charge/discharge experiments were conducted at 77 K. In this paper, the test coils were fabricated using the NI, MI, and SMI winding methods and the contact resistance of each coil was investigated. The results show that the SMI winding method can be used to create expected or controllable contact resistance. [ABSTRACT FROM AUTHOR]

Quadrupole magnets located at the front end of an in-flight fragment (IF) separator in a heavy ion accelerator have large heat loads due to neutron radiation. Thus, high-temperature superconducting (HTS) magnets are used instead of low-temperature superconducting (LTS) magnets because of their high cooling efficiency and thermal stability. The cooling system of the HTS magnet uses circulation of cold helium gas. The circulating helium gas is provided from the distribution box, where helium gas lines are divided into 7 pairs of small helium lines corresponding to 7 HTS magnets. To cool down the 7 HTS magnets with different heat loads, the mass flow rate of each magnet should be individually controlled by monitoring the temperature of the magnets. This paper describes the cooling system for the 7 HTS magnets considering the heat load of each magnet and the thermohydraulic characteristics of the cooling system, including a heat exchanger, a cryogenic blower, control valves, etc. The helium mass flow rates for each magnet and the temperature at the outlet of the magnet are determined so that the magnets operate below 45 K. The optimal helium mass flow rates for each magnet were determined by analyzing the correlation between the magnet outlet temperature and flow rate. [ABSTRACT FROM AUTHOR]

The authors have proposed a performance evaluation system (PES) for large-scale high temperature superconducting (HTS) wind power generators, which produces strong electromagnetic force and high torque due to the high excitation current and the high magnetic load of the machine, based on the computer simulation results. The PES can physically test the structural stability of HTS coils and armatures against high torque and the effect of the magnetic field before mounting the HTS coil on the generator. This paper deals with the design, fabrication, and performance testing of a full-scale HTS coil to be installed in the PES, a performance analysis system for a 10 MW HTS wind power generator. The HTS coil with metal-insulation consists of four racetrack-type single coils with 310 turns per layer. The manufactured HTS coil was tested at 77 K with and without an iron-core. As a result, the critical currents of the tested HTS coils with and without the iron-core were 90 A and 106 A, respectively. Compared to the simulation results, it was found that the magnitude of the magnetic field was the same. These results will be effectively used to study and fabricate high magnetic field coils for HTS applications, as well as the PES being fabricated. [ABSTRACT FROM AUTHOR]

Aqueous graphene oxide inks are promising to fabricate a large-area thin film which can be utilized in various applications such as sensors and energy storage and conversion. In this work, we experimentally demonstrate a facile way to controllably fabricate wrinkled structures on the surface of graphene oxide films by using a drop-casting method. Simple drop-casting of the graphene oxide ink enabled to fabricate randomly distributed wrinkles uniformly over the entire film deposited after water was totally evaporated. Deposition mechanism after a single drop-casting was clearly demonstrated, which involves graphene oxide flake transport, aggregation/deposition at the pinned contact edge of a sessile droplet during water solvent evaporation and also buckled deformation(wrinkle formation) of the deposited graphene oxide thin film due to compressive stress by the receding water droplet contact line. Multiple drop-casting on the initially formed wrinkled structures of the graphene oxide film allowed the wrinkles to grow in their width and height linearly by increasing the number of drop-casting, which resulted in the increase of the size polydispersity and area density of wrinkles. The wrinkle growth mechanism during multiple drop-casting was explained in the perspective of collision and accumulation of graphene oxide flakes dispersed within additional dropped droplet on the initially formed wrinkles during water evaporation and droplet contact line recession, which was supported by high-resolution imaging of the films using scanning electron microscopy (SEM) and atomic force microscopy (AFM). This work suggests that the behavior of the graphene oxide flakes dispersed within a sessile droplet can affect surface structures of deposited thin films, and it can be foundational to extend the simple multiple drop-casting strategy to controlled fabrication of various 2D nanomaterial thin films with wrinkled structures by appropriately controlling ink solution and evaporation conditions, which can be used in a variety of functional applications. [Display omitted] • A facile way is demonstrated to controllably fabricate wrinkled structures on the surface of graphene oxide thin films. • Deposition mechanism of graphene oxide thin films is clearly demonstrated, involving graphene oxide transport, aggregation/deposition, solvent evaporation and wrinkle formation. • The wrinkle growth mechanism during multiple drop-casting is explained in the perspective of collision and accumulation of graphene oxide flakes. [ABSTRACT FROM AUTHOR]

There is a paucity of research characterizing suicide-related factors in victims of early trauma (ET). This cross-sectional study investigated an increase in trait impulsivity of ET victims with suicidal ideation or behavior and its role in severity of psychopathologies and experienced stress. Using data of 401 Korean suicidal ideators and attempters, trait impulsivity, severity of psychopathologies, and stress levels in addition to sociodemographic and clinical characteristics were compared between the ET group and the no ET group. Three first-order factors of trait impulsivity measured in Barratt Impulsive Scale-11 (cognitive instability, motor, and [lack of] perseverance) as well as depression, anxiety, overall stress level, and stress from social relationships were significantly elevated in the ET group. Owing to the long-lasting neurobiological influences of ET, it is recommended clinically that victims be carefully monitored for the development of mental distress, such as depression and anxiety, even in adulthood. [ABSTRACT FROM AUTHOR]

To date, many transgenic (TG) chicken lines have been developed, but few studies have performed a comparative analysis of their mortality, growth, and egg productivity. Previously, we reported the production of 3D8 scFv TG chickens showing antiviral activity. Here, we performed a biometric characterization of TG offspring female chickens. We selected 40 TG and 40 non-TG offspring female chicks among newly hatched chicks produced via artificial insemination of semen from heterotypic 3D8 scFv males into wild-type female chickens. Serum was collected at 14 wk of age, and serum concentrations of biochemical parameters, cytokines, and sex hormones were analyzed. Mortality and growth were monitored daily from 1 to 34 wk, egg productivity was monitored daily from 20 to 34 wk, and the weekly average values were used for analyses. Some serum parameters and cytokines were significantly different between non-TG and TG offspring female chickens. The levels of phosphorus ( PHOS ), total protein ( TP ), albumin ( ALB ), globulin ( GLOB ), and alanine aminotransferase ( ALT ) were significantly higher in non-TG chickens (P < 0.05). The levels of alkaline phosphatase ( ALP ) and gamma-glutamyltransferase ( GGT ) were significantly higher in TG chickens (P < 0.05). The levels of insulin growth factor-1 ( IGF-1 ), interferon-gamma ( INF-γ ), interleukin-4 ( IL-4 ), and IL-8 were significantly lower in TG chickens (P < 0.05). Despite these differences, the mortality rates, body weight, egg production rates, and egg weight were not significantly different in the experimental groups of non-TG and TG offspring female chickens (P > 0.05). In conclusion, ubiquitous expression of the 3D8 scFv gene in TG offspring female chickens does not affect some biometric characteristics, including mortality, growth, and egg productivity. [ABSTRACT FROM AUTHOR]

This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application. [ABSTRACT FROM AUTHOR]

The authors presented practical fabricated specifications of a prototype 10kW class high-temperature superconductor (HTS) direct current (DC) induction heating machine and analyzed its operational characteristics including the system's efficiency and the temperature distribution of the aluminum billet in detail In this paper, we discussed the fabrication process and focused particularly on the practical operating results of the HTS DC induction heating machine. The major operating characteristics of the HTS magnet under each stage were analyzed in detail. Detailed efficiency was investigated through the measuring of the realtime motor input and the billet temperature. Through a monitoring system, critical parameters were measured in real-time operation. The total heating time to 500 C of the billet's temperature was 400 s at 0.25 T at the center of the billet. These research outcomes are expected to be useful for the commercial design of a large-scale 2G HTS DC induction furnace for industrial fields. [ABSTRACT FROM AUTHOR]

Conventional induction heaters have been in operation in metal and related industries with poor energy efficiencies of only 50–60%. Also, the efficiency of atmosphere furnace, one of the various heating facilities for metal billets, is about 20%. Hence, a high temperature superconducting (HTS) DC induction heating machine to heat a rotating metal billet under uniform magnetic field generated by the 2G HTS magnet with about 80–90% of the system energy efficiency has been researched in this paper. We presented practical design specification, operational characteristics, and temperature distribution on a 10 kW class HTS DC induction heating machine which had been built and tested. The saturated temperature of an HTS no-insulated(NI) coil in the cryostat fabricated with 100 A of the operating current reached 45.9 K and the magnetic field at the centre point between two iron cores measured 0.2 T. The rotating machine for 4.1 kg of the aluminum billet was tested on 1760 rpm of the rated rotating speed. The final temperature of the aluminum billet has risen up to 500 °C for 480 s. The research outcomes are expected to be useful for the design of a large scale HTS DC induction heating machine in industries. [ABSTRACT FROM AUTHOR]

This paper describes the design specifications and performance of a real toroid-type high temperature superconducting (HTS) DC reactor. The HTS DC reactor was designed using 2G HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The target inductance of the HTS DC reactor was 400 mH. The expected operating temperature was under 20 K. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. Performances of the toroid-type HTS DC reactor were analyzed through experiments conducted under the steady-state and charge conditions. The fundamental design specifications and the data obtained from this research will be applied to the design of a commercial-type HTS DC reactor. [ABSTRACT FROM AUTHOR]