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Determining the phase-transition temperature is crucial in the design of molten salt reactors, as operational temperatures need to be established considering the safety margins related to the thermodynamic stability of the molten salt system. This study introduces a novel approach to determine the phase-transition temperature based on rapid electrical conductivity measurements using a microsecond-scale staircase voltammetry technique. The phase-transition temperature is determined near distinct points where the electrical conductivity abruptly changes, indicating phase transitions. The phase-transition temperatures of three LiCl–KCl molten salt systems, determined using the proposed approach based on electrical conductivity measurements, are with relative errors less than 3% compared with reported phase transition data based on conventional thermal analysis techniques.

Abstract The magnetic and interface properties of [Pt/Co/Pt] were investigated. First, the magnetic properties were determined from the magnetic dead layer plots, in which the Co layer was considered as two distinct parts representing different magnetic properties. The two parts with low and high t Co ranges are close to and away from the top interface (Co/Pt), respectively. The part close to the top interface shows a smaller magnetization (M) value and nonlinear behavior. However, the other part shows a higher M value closer to the bulk value and a linear behavior. The nonlinear behavior of the M values of the low t Co range was converted to an impurity level using simple assumptions. The results showed the effect of the top Pt layer on the magnetic properties of the Co layer. The results clearly demonstrate that magnetometry could be utilized as a means to understand the interface quality of magnetic multilayer systems.

Most thickness measurement techniques using X-ray radiation are unsuitable in field processes involving fast-moving organic films. Herein, we propose a Compton scattering X-ray radiation method, which probes the light elements in organic materials, and a new simple, non-destructive, and non-contact calibration-free real-time film thickness measurement technique by setting up a bench-top X-ray thickness measurement system simulating a field process dealing with thin flexible organic films. The use of X-ray fluorescence and Compton scattering X-ray radiation reflectance signals from films in close contact with a roller produced accurate thickness measurements. In a high-thickness range, the contribution of X-ray fluorescence is negligible, whereas that of Compton scattering is negligible in a low-thickness range. X-ray fluorescence and Compton scattering show good correlations with the organic film thickness (R2 = 0.997 and 0.999 for X-ray fluorescence and Compton scattering, respectively, in the thickness range 0–0.5 mm). Although the sensitivity of X-ray fluorescence is approximately 4.6 times higher than that of Compton scattering, Compton scattering signals are useful for thick films (e.g., thicker than ca. 1–5 mm under our present experiment conditions). Thus, successful calibration-free thickness monitoring is possible for fast-moving films, as demonstrated in our experiments.

For ensuring nuclear safeguards, we report the analytical signal-detection performance of thermal ionization mass spectrometry (TIMS) with continuous heating for the measurement of isotopic ratios in samples containing ultra-trace amounts of uranium. As methods for detecting uranium signals, peak-jumping mode using a single detector and static mode using multiple detectors were examined with U100 (10% 235U-enriched) uranium standard samples in the femtogram-to-picogram range. Uranium isotope ratios, n(235U)/n(238U), were measured down to levels of 1 fg and 3 fg in static and peak-jumping modes, respectively, while n(234U)/n(238U) and n(236U)/n(238U) values were measured down to levels of 100 fg in both modes. In addition, the dependency of the 238U signal intensity on sample quantity exhibited similar tendencies in both modes. The precisions of the isotope ratios obtained in the static mode over all sample ranges used in this study were overall slightly higher than those obtained in peak-jumping mode. These results indicate that isotope ratio measurements by TIMS with continuous heating are almost independent of the detection method, i.e., peak-jumping mode or static mode, which is characteristic of isotope-ratio measurements using the TIMS method with continuous heating. TIMS with continuous heating is advantageous as it exhibits the properties of multiple detectors within a single detector, and is expected to be used in various fields in addition to ensuring nuclear safeguards.

Abstract The coverage and temperature dependence of ZIRLO cladding with H2O adsorption are studied using synchrotron-based high-resolution photoemission spectroscopy (HRPES). Based on the analytical results of the Zr 3d, O 1 s, C 1 s, and Sn 3d HRPES profiles prior to H2O adsorption, we determine the surface compositions of O2−, hydroxyl OH−, chemisorbed H2O, zirconium carbide, adventitious carbon, Sn metal, and SnO2 in ZIRLO. When ZIRLO is exposed to H2O molecules, the relative proportion of zirconium metal decreases, whereas that of the total zirconium oxides increases, suggesting the reaction between H2O and the zirconium metal in ZIRLO. On annealing a sample with 1000 L H2O on ZIRLO at 300 °C, Zr2O3 and ZrO2 decompose, and oxygen diffuses into the bulk, thereby reducing the oxidation states of zirconium on the surface. Moreover, at this temperature, the excess H2O molecules on ZIRLO are thoroughly desorbed and tin element is diffused into the bulk in ZIRLO.

Isotopic analyses of plutonium and low-enriched uranium mixtures with particle sizes of 0.6–3.3 μm were performed using thermal ionization mass spectrometry with a continuous heating method to verify its effectiveness for the accurate analysis of minor isotopes without sample pretreatment. The mixed particles used in this study were prepared from a mixed solution of plutonium (SRM 947) and uranium (U010, 235U 1% enriched) reference materials. The isotope ratios for plutonium in the individual mixed particles, including 238Pu/239Pu, 241Pu/239Pu as well as 240Pu/239Pu, and 242Pu/239Pu, were in good agreement with the certified values despite the isobaric interference of 238U and 241Am. The isotope ratios for uranium in the mixed particles also agreed well with the certified values within the range of error. However, the isotope ratios for minor isotopes, such as 234U and 236U, in the particles with diameters of less than approximately 1.8 μm could not be measured because numbers of 234U and 236U atoms in analyzed particles are too low. These results indicate that thermal ionization mass spectrometry with a continuous heating method is applicable for the analysis of trace amounts of plutonium isotopes, including 238Pu and 241Pu, despite the presence of the respective isobars 238U and 241Am in the microsamples.

Abstract In this study, we derive analytical expressions for the critical switching current density induced by spin Hall effect in magnetic structures with the first- and second-order perpendicular magnetic anisotropy. We confirm the validity of the expressions by comparing the analytical results with those obtained from a macrospin simulation. Moreover, we find that for a particular thermal stability parameter, the switching current density can be minimized for a slightly positive second-order perpendicular magnetic anisotropy and the minimum switching current density can further be tuned using an external magnetic field. The analytical expressions are of considerable value in designing high-density magnetic random access memory and cryogenic memory.

Left ventricular aneurysm (LVA) and false aneurysm are complications of acute myocardial infarction, trauma, and cardiac surgery. Left ventricular false aneurysm (LVFA) is a particularly catastrophic complication owing to its high propensity for rupture. Surgical resection should be considered for LVFA occurring within three months after myocardial infarction or development of congestive heart failure. In this report, we describe a case of acute heart failure with LVA and LVFA occurring in stage as a complication of myocardial infarction in a 55-year-old man. The patient was also at risk of brain ischemia due to abnormal vessel status and a previous cerebrovascular accident with left-sided weakness. Successful perioperative anesthetic management was achieved by focusing on maintaining marginal upper normal blood pressure to ensure cerebral perfusion and to reduce the risk of false aneurysm rupture.

Massive air leakage through a lacerated lung produces inadequate ventilation and hypoxemia. Tube exchange from a single to double lumen endotracheal tube (DLT), and lung separation to maintain oxygenation, are challenging for seriously injured patients. In this case report, we aim to describe how a bronchial blocker (BB) makes it easier to perform a lung separation in this situation; it also increases the overall safety of the procedure. A 35-year-old female (163 cm, 47 kg) suffered from blunt chest trauma due to a traffic accident; the accident caused right-sided lung laceration with massive air leakage. Paradoxically, positive ventilation worsened SaO2 and leakage increased through a chest tube. We introduced BB while the patient was still awake: Left-side one-lung ventilation (OLV) was established and anesthesia was induced. After PaO2 was maximized with OLV, we changed the endotracheal tube to DLT without a hypoxic event. By BB placement, we maintained PaO2 at a secure level, conducted mechanical ventilation and exchanged the tube without deterioration.

BackgroundSevoflurane anesthesia commonly causes emergence agitation (EA) in children. One previous study has reported that the use of nitrous oxide (N2O) during the washout of sevoflurane may reduce EA by decreasing the residual sevoflurane concentration, while many animal studies suggest that N2O poses a potential risk to children. The present study was designed to compare EA in children assigned to receive sevoflurane with N2O (group N) or sevoflurane alone (group S).MethodsWe enrolled 80 children aged 3-10 years. Anesthesia was induced with 5 mg/kg thiopental sodium, 0.6 mg/kg rocuronium and 0.5 mg/kg ketorolac, and was maintained with 50% N2O and sevoflurane in group N or with sevoflurane alone in group S. The sevoflurane concentration was adjusted with a bispectral index (BIS) of 40-60. After completion of the surgery, N2O and sevoflurane were simultaneously discontinued and replaced with oxygen (O2) at 6 L/min. End-tidal sevoflurane concentration (Et Sevo) (%), BIS at the end of surgery, Et Sevo at recovery of self-respiration and emergence profiles were recorded. EA occurrence, pain score and rescue fentanyl consumption were assessed in the postanesthesia care unit.ResultsEt Sevo was significantly lower in group N (1.9%) than in group S (2.3%) at the end of surgery. However, there were no differences in Et Sevo at recovery of self-respiration, emergence times, the incidence of EA, pain score or dose of rescue fentanyl between the groups.ConclusionsIn children undergoing adenotonsillectomy with preemptive ketorolac, anesthetic maintenance using sevoflurane alone does not affect the incidence of EA or emergence profiles compared to anesthetic maintenance using sevoflurane with N2O.

Unexpected tracheal narrowing was observed in a patient with Duchenne muscular dystrophy during a corrective operation for thoracolumbar scoliosis. As the operating time progressed, peak airway pressure and end-tidal CO2 increased gradually in the prone position. We found a floppy portion of the trachea using fiberoptic bronchoscopy (FB) in the prone position. We advanced a wire-reinforced tube toward the carina beyond the lesion. This allowed correction of the ventilatory abnormalities. We encountered another patient scheduled for the same operation. We performed FB in advance before the position change and observed a narrowed portion of trachea. We advanced the tracheal tube under FB beyond the pathologic portion and then moved the patient into the prone position. The operation was done successfully without any problems.

Strong interlayer exchange coupling (IEC) and high post-annealing stability are demonstrated for perpendicular synthetic ferrimagnets (p-SyFs) with [Pt/Co]6/Ru/[Co/Pt]3 structures. The observed IEC strength was 2.55 ergs/cm2 for a Ru thickness of 0.35 nm, representing the highest value achieved up to date for similar structures. The IEC remained strong even after annealing at 450oC, for the practically important Ru layer thickness of 0.85 nm. The biquadratic IEC, a parameter quantifying the pinhole effects in SyFs, was confirmed by analyzing the experimental results by using the total energy functional, and its strength increased with decreasing the temperature and Ru layer thickness.

BackgroundThe aim of this study was to compare the streamlined liner of the pharynx airway (SLIPA) with the classic laryngeal mask airway when used by novice personnel.MethodsThere were 114 patients enrolled into this study who underwent general anesthesia were randomly allocated into one of 2 groups; LMA group (n = 57) or SLIPA group (n = 57). After insertion, insertion success rate, insertion time, and hemodynamic responses to insertion were accessed. After surgery, postoperative airway morbidity (sore throat, dysphonia, dysphagia) were evaluated.ResultsThe SLIPA was successfully inserted in 96% of patients (55/57) and the LMA in 93% (53/57) (P = 0.408). First attempt success rates were 88% (44/57) and 77% (50/57) in the SLIPA and the LMA (P = 0.142). The successful insertion time in SLIPA group (33.4 ± 11.0 sec) was significantly shorter than that of LMA group (38.8 ± 16.6 sec) (P = 0.048) and the insertion time at the first attempt was also shorter in SLIPA group (31.0 ± 6.3 sec) than LMA group (34.7 ± 8.6 sec) (P = 0.013). There was no statistically significant difference between the two groups in hemodynamic responses and postoperative airway morbidity.ConclusionsThe SLIPA was similar to the LMA in insertion success rate, hemodynamic response, and postoperative airway morbidity by novice personnel. The insertion time at the first attempt and successful insertion time of the SLIPA were significantly shorter than those of the LMA. Therefore, the SLIPA could be a useful alternative to the LMA as primary SGA for novice personnel.

BackgroundHydrogen sulfide (H2S) produces a protective effect against myocardial ischemia and reperfusion injury. Sevoflurane, which is used for anesthesia in cardiac problem patients, also has a protective effect. This study is designed to reveal the effects of H2S under sevoflurane using rat hearts.MethodsThe hearts were Langendorff-perfused, subjected to 30 minutes ischemia and 60 minutes reperfusion. Group I was a control group. The other groups were pretreated for 15 minutes before ischemia as follows: 1.6% sevoflurane for group S; 18.5 µM H2S S for group H; and 1.6% sevoflurane and 18.5 µM H2S simultaneously for group HS. Hemodynamics and the infarct size were measured.ResultsGroup HS presented depressed hemodynamics during pretreatment. LV function in group HS achieved better recovery than group I after reperfusion. The infarct size of groups S, H and HS was smaller than group I, while there were no differences between groups S, H and HS.ConclusionsExogenous H2S did not enhance the preconditioning effects of sevoflurane. Rather, the results suggest that H2S under sevoflurane might depress hemodynamics.

BackgroundLipid-emulsion propofol (LP) has cardioprotective effects against ischemia-reperfusion injury, but it has lipid-related side effects. Microemulsion propofol (MP) is a lipid-free propofol emulsified with 10% purified poloxamer 188 (PP188). PP188 is a nonionic surfactant and has cardioprotective effects. However, some reports have suggested that reduced cardioprotective effects were observed when the cardioprotective agents were used in combination even though each cardioprotective agent has cardioprotective effects. The aims of this study were to examine and compare the cardioprotective effects of MP and LP.Methods50 isolated rat hearts were perfused with modified Kreb's solution. They were divided into 4 groups and underwent 30 minutes of ischemia and 60 minutes of reperfusion. Control group: ischemia-reperfusion was performed without treatment. LP, MP and PP groups: LP, MP and PP188 were infused during the pre-ischemic and reperfusion period, respectively. Hemodynamic parameters and coronary effluent flow rate (CEFR) were measured. Infarct size was determined using triphenyl-tetrazolium staining.ResultsIn the MP group, systolic pressure was maintained near baseline, the systolic pressure was higher than that in the other groups and HR was lower than that in the other groups during reperfusion. Diastolic pressure was transiently increased in the PP group after treatment and at 5 minutes after reperfusion compared with that in the control group and in the the LP group. There were no differences in dP/dtmax and CEFR between groups. Infarct size in the LP, MP and PP groups was smaller than that in the control group, but there were no significant differences between these three groups.ConclusionsMP has cardioprotective effects similar to those of LP. MP can be used for cardiac anesthesia in cases with ischemia-reperfusion injury to avoid the lipid-related side effects of LP.

Elbow tuberculosis is a rare disease which accounts for 1-3% of all cases of osteoarticular tuberculosis. The diagnosis of tuberculous arthritis is very difficult in most clinical situations because of the insidious onset, indolent process, and mild and non-specific local or systemic symptoms. Thus, the confirmatory diagnosis and effective treatment for tuberculous arthritis are delayed until the disease progresses to an advanced stage in many clinical settings. Herein we report a case of septic arthritis of the elbow due to Mycobacterium tuberculosis as a result of misdiagnosis and delayed treatments.

Tracheal bronchus (TB) is an aberrant, accessary or ectopic bronchus arising almost exclusively from the right side of the tracheal wall above the carina. In our center, 673 bronchoscopic examinations were performed from 2009 to 2011 in patients undergoing one lung ventilation (OLV) and 3 TB were found. The incidence of a TB at bronchoscopy was 0.45% in our research, which is consistent with the reported incidence range from 0.1-5%. The clinician should consider the possibility of anomalous right upper lobe bronchus and perform bronchoscopy prior to the right bronchial blocker insertion, when left-sided OLV using bronchial blocker is planned. Also, for the patient with TB, a double lumen tube insertion is recommended than a blocker insertion to achieve OLV completely.