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In this work, two-dimensional crystalline C3N4 (CCN) was obtained by promoting the self-condensation reaction of dicyandiamide in an air atmosphere via the molten salt method. Studies show that compared with polymer-C3N4 (PCN) ((9.8 m2/g)), CCN has a larger specific surface area (77.1 m2/g)) and better crystallinity. Additionally, the resistance of CCN in the air is 40 MΩ, 1250 times lower than that of polymer-C3N4 (PCN) (∼50000 MΩ). Secondly, when 50 ppm toluene gas analysis flows into the CCN based gas sensor at room temperature, the gas response value is 350. The CCN based gas sensor works for 60 days, or after 25 cycles continuously, the gas response value remains at about 350 (Rg/Ra), which is due to the excellent crystallinity, optimized π conjugate system, and enhanced interlayer van der Waals of CCN. Additionally, the critical effect of crystallinity on the gas sensitivity of carbon nitride is also discussed in detail.

For improving the sensor performance of molybdenum disulfide (MoS2), the modification of surface properties is essential. In this study, the surfaces of MoS2 nanoparticles with a mixture of 1T (metallic) and 2H (semiconductor) (1T/2H-MoS2) prepared solvothermally were modified by O2 plasma irradiation to enhance their humidity-sensing properties. The O2 plasma irradiation of MoS2 induced MoO3 formation on the surfaces. The amount of MoO3 increased with increasing O2 plasma irradiation time. The specific surface area, as well as total pore volume, increased after O2 plasma irradiation from 28 m2/g and 0.089 cm3/g to 185 m2/g and 0.279 cm3/g, respectively. The pore size distribution shifted to a lower value after O2 plasma irradiation. These results suggest that the O2 plasma irradiation can modify the surface nature of 1T/2H-MoS2 nanoparticles. The humidity-sensing properties of the obtained samples were evaluated with various relative humidity (RH) values. When the O2 plasma-irradiated MoS2 sensor was exposed to a higher RH, a higher response was obtained. The sensor response of the O2 plasma-irradiated MoS2 nanoparticles was significantly enhanced to around 100% at 95% RH compared with the sample before the O2 plasma irradiation. As a demonstration of a practical application, the materials were used for the sensing of human breath. The breath testing indicated a good response, and the sensor also distinguished wet and dry hands clearly. These results strongly suggested that the O2 plasma-irradiated MoS2 can be applied for breath testing as well as in skin monitoring devices.

In general, a rapid quenching is required to obtain an amorphous metal. It is known that an intensive ultrasonication generates a very high temperature within cavitation bubbles in a very short moment, which enables a rapid quenching process in a liquid phase synthesis. In this study, the sonochemically-derived "amorphous iron" from Fe(CO)5 was carefully examined by XRD, TEM, TG-DTA. The product was found to be an amorphous containing a certain amount (∼15%) of volatile component that can be removed by heating in a nitrogen flow. After annealed in the inert atmosphere at 600°C, cooled down to room temperature, and then exposed in air (oxygen), the sample showed a strong exotherm accompanied by a weight gain. This is due to oxidation of fine metallic iron. Experimental operations of such a reactive material were examined.

Adsorption and photocatalytic decomposition behaviors of gas-phase acetaldehyde (CH3CHO), together with carbon dioxide (CO2) formation have been measured for pure titania (TiO2) powders with three types of polymorphs (anatase, brookite, and rutile) under UV-light illumination, and assessed by a kinetic model that takes into account the immediate decomposition of CH3CHO attached on the surface, and the gradual decomposition of CH3CHO adsorbed on the surface. Experimental data are well reproduced by the present model, highlighting how adsorption-related pathways markedly contribute to overall CH3CHO removal kinetics even for pure titanias. Although the initial removal rate depends on the surface area, which affects the adsorption capacity, it is suggested that specific surface area-based adsorbability and decomposition reactivity are enhanced by heightened crystallinity. Our kinetic analysis demonstrates that anatase exhibits the highest photocatalytic activity as a result of superior adsorbability, as well as superior decomposition reactivity, compared to other polymorphs.

The structure, porosity, and adsorption properties of mixed metal oxides (MMO) were investigated according to the physical property of the starting materials. Layered double hydroxides (LDH), the pristine MMO, were prepared to have the same composition of Mg2Al(OH)6(CO3)0.5, but with different particle size. The prepared LDH were calcined at 400 °C to obtain MMO named CMO, HMO, and UMO corresponding to the pristine MMO synthesized by coprecipitation, hydrothermal treatment, and urea hydrolysis method, respectively. The particle sizes of CMO, HMO, and UMO were comparable to those of the pristine MMO in the order UMO > HMO > CMO; on the other hand, the crystallite sizes were almost the same as each other, regardless of the pristine MMO. According to the high-resolution transmission electron microscopy and X-ray diffraction, we could suggest that a single particle of MMO was composed of smaller domains of metal oxide crystallite. Consequently, small MMO particle tended to have interparticulate macropore, while large MMO particle had more possibility of containing intraparticulate mesopores, which was cross-confirmed by the N2 adsorption–desorption isotherms. Toluene and water vapor adsorption tests on three different MMO showed that the intraparticulate mesopores were advantageous to adsorb a variety of adsorbate. It was therefore concluded that MMO obtained by calcination of LDH would have high adsorption property when the pristine LDH has large particle dimension, thanks to the large portions of intraparticulate mesopores.

Herein, we report the self-assembly of a synthetic vanilloid receptor (VR) peptide that selectively binds capsaicin. We synthesized a 26-mer peptide-YSEILFFVQS-HHHHHH-LAMGWTNMLY (S3HS4)-comprising two chemoreceptor domains of transient receptor potential channel (TRPV1) linked by a hexahistidine sequence. High-speed atomic force microscopy (AFM) imaging in water revealed that the peptide structures alternated rapidly between wedge shape and linear forms. Circular dichroism spectroscopy showed that 65% of the amide units in the peptide chain adopted an α-helix structure, which was ascribed to the chemoreceptor domains. S3HS4 developed well-packed monolayers at the Ni-treated thiolated nitrilotriacetic acid self-assembled monolayers by chelation of the hexahistidine segment, as characterized by infrared spectroscopy and AFM, which exhibited statistically constant specific height. Therefore, S3HS4 was expected to fold spontaneously upon chelation, and the resulting helix-turn-helix conformers developed films while uniformly oriented: the tilt angle was 69° from the surface normal to the substrate. According to microgravimetric analysis using a quartz crystal microbalance (QCM), the adsorption was 84 ± 47 pmol cm

JSFR is going to adopt an advanced fuel handling system. As for ex-vessel spent fuel handling, a transfer pot with two fuel subassembly positions has been developed so as to shorten refueling period increasing plant availability. The pot is required to provide sufficient cooling capability in case of transportation malfunction. In this study, a three dimensional analysis model for heat transfer evaluation of the JSFR fuel transfer pot has been developed. The heat transfer models inside and outside the pot have been validated by reference experiments. Using the developed three-dimensional model, the JSFR fuel transfer pot has been analyzed. For a simpler design tool, a two dimensional analysis model has been developed. Comparison of the three and two dimensional analyses shows that two dimensional analyses could estimate pot cooling performance conservatively.

Japan sodium-cooled fast reactor is going to adopt an advanced fuel handling system. As for ex-vessel spent fuel handling, a transfer pot with two fuel subassembly positions has been developed so as to shorten refueling period increasing plant availability. The pot is required to provide sufficient cooling capability in case of transportation malfunction. To evaluate cooling capacity of the transfer pot, a mockup pot has been fabricated and heat transfer experiments have been conducted on the mockup pot.

A conceptual design study of Japan Sodium-cooled Fast Reactor (JSFR) is in progress in the Fast Reactor Cycle Technology Development (FaCT) project in Japan. In the design of JSFR, a selector valve...

Two patients in whom accidental hepatic artery occlusion (HAO) occurred after hepatic resection (Hx) were reported. A 59-year-old female who underwent Hx for hepatocellular carcinoma with underlying liver cirrhosis developed HAO on postoperative day (POD) 14 and died of hepatic failure on POD 23. The autopsy findings showed multiple necrosis in the remnant liver and an extraluminal hematoma of the hepatic artery, suggesting an injury caused by Pringle's maneuver. The second case was a 53-year-old male who underwent Hx for cholangiocarcinoma without any underlying liver disease. He developed HAO on POD 6, and radiological studies indicated a pseudoaneurysma formation and severe stenosis of the hepatic artery. It was speculated that the cause of the HAO was intraluminal injury of the hepatic artery during an angiographic study conducted prior to Hx. Partial arterialization of the portal vein was performed, following which his liver function test results improved. In both cases, measuring the serum hepatocyte growth factor level and the hepatic vein oxygen saturation proved useful, not only for determining the degree of liver injury, but also for predicting the outcome after treatments for HAO. Furthermore, the partial arterialization of the portal vein for HAO after Hx may rescue the normal remnant liver.

A 62-year-old man developed a refractory duodeno-cutaneous fistula after undergoing an operation for postoperative adhesion. Five previous simple anastomotic closure failed at another hospital. He underwent long-term intraveous parental hyperalimentation and showed hypoablbuminemia. We started elementary diet and performed an adhesiotomy electively. After successful dissection of postoperative adhesion, the duodenal defect was covered with elevated jejunum, and side-to-side duodeno-jejunostomy was performed. To facilitate decompression of he duodenum, a cholecystostomy and insertion of a cannula into the pancreatic duct was carried out. His postoperative course was uneventful. The large duodenal defect was a good candidate for a side to side anastomosis using elevated jejunal segment in such as this case.

The incidence and circumstances of colonization by methicillin-resistant Staphylococcus aureus were prospectively investigated. Among 404 patients, 15 (3.7%) were carriers on admission, and 43 (10.6%) became colonized, mainly after surgical operation. A different mode of transmission was suggested in each ward.

The first loop operation tests of the Tritium Systems Test Assembly (TSTA) with 100 grams-level of tritium were performed at the Los Alamos National Laboratory (LANL) in June and July, 1987. The July run was resumption of the June run, which was halted because of a loss of cryogenic refrigerant in the hydrogen isotope separation system.

Cryogenic distillation experiments were performed at TSTA with H-D-T system by using a single column and a two-column cascade. In the single column experiment, fundamental engineering data such as the liquid holdup and the HETP were measured under a variety of operational conditions. The liquid holdup in the packed section was about 10--15% of its superficial volume. The HETP values were from 4 to 6 cm, and increased slightly with the vapor velocity. The reflux ratio had no effect on the HETP under the condition that the vapor velocity was almost constant. For the two-column experiment, dynamic behavior of the cascade was observed.

In March of 1988 full operation of the 4-column isotope separation system (ISS) was realized in runs that approximated the design load of tritium. Previous operations had been fraught with operating difficulties principally due to external systems. This report will examine the recent highly successful 6-day period of operation. During this time the system was cooled from room temperature, loaded with hydrogen isotopes including 109 grams of tritium, integrated with the transfer pumping, impurity injection, and impurity removal systems, as well as the remote computer control system. At the end of the operation 12 grams of tritium having a measured purity of 99.987% (remainder deuterium) were offloaded from the system. Observed profiles in the columns in general agree with computer models. A Height Equivalent to a Theoretical Plate (HETP) of 5.0 cm is confirmed.

An experimental apparatus has been developed to carry out tritium permeation experiments for candidate first-wall materials subjected to a high flux of low energy tritium ions, and installed in a g...