Phase transition and hydrogenation properties of Ce2Ni7-type Pr2Co7 during the hydrogen absorption process

The crystal structure and hydrogenation properties of Pr₂Co₇ with a Ce₂Ni₇-type structure were investigated by X-ray diffraction (XRD) and observation of the pressure–composition (PC) isotherms. The reversible hydrogen capacity reached 0.8 H/M, and two plateaus were observed in the absorption–desorption process. The two observed hydride phases, Pr₂Co₇H_2.7 and Pr₂Co₇H_7.2, were determined to have hexagonal (space group: P6₃/mmc) and orthorhombic (space group: Pbcn) crystal structures, respectively. The crystal structure transformed in the order of hexagonal with a Ce₂Ni₇-type structure (original alloy) → same Ce₂Ni₇-type structure (Pr₂Co₇H_2.7) → orthorhombic (Pr₂Co₇H_7.2). The crystal lattice of the Pr₂Co₇H_2.7 underwent anisotropic expansion along the c-axis of the original alloy, whereas that of Pr₂Co₇H_7.2 exhibited isotropic expansion. The full width at half maximum (FWHM) values for the original alloy and hydride phases during the hydrogen absorption–desorption process were evaluated based on the XRD data. The FWHM values for the main peaks decreased as the hydrogen content increased during the absorption process, indicating that the number of lattice defects did not increase upon hydrogenation. The plateau pressures during the absorption process of the second cycle were the same as those of the first cycle, which also suggests that there were no lattice defects.     

Comparison of Gelation Mechanism of Surimi between Heat and Pressure Treatment by Using Rheological and NMR Relaxation Measurements

ABSTRACT: The stress-relaxation and nuclear magnetic resonance (NMR) proton spin-spin relaxation time (¹H T₂) measurements were performed to elucidate the gelation mechanism of heated and pressurized surimi gels. Numerical inverse Laplace transformation of the stress-relaxation data showedlarge distributions of stress-relaxation times and the Kohlrauch-Williams-Watts (KWW) equation described well the stress-relaxation process for each gel. NMR measurement gave information about the content of the exposed protein surface. From these results it is considered that the heat treatment induces the denaturation and re-aggregation of protein, which contribute to the formation of strong network structure. On the other hand, the pressure treatment contributes to the formation of weak cross-links made by the aggregation of protein in native form.     

Pulmonary actinomycosis with "balls-in-a hole" appearance diagnosed by examination of bronchial lavage fluid

A 49-year-old man was referred to our hospital because of abnormal chest X-ray findings. Chest X-ray films showed infiltrative opacities in the right lung, and histological findings of a transbronchial biopsy specimen showed non-specific inflammation. The patient was treated with Ofloxacin for one month. After the treatment, chest X-ray films showed that the infiltrative opacities in the right upper lobe had decreased, but that opacities in the right lower lobe had increased, with an air meniscus sign. A chest computed tomography scan at the same time revealed that the remaining opacities contained multiple mass-like lesions within a cavity in the right S6, appearing as "balls in a hole". One year after the first visit, the patient visited the hospital again because of cough and sputum. A chest X-ray film showed that the size of the cavity in the right lower lobe had increased. The histological findings from a fresh transbronchial biopsy specimen revealed a non-specific inflammation again; however, black clots obtained from bronchial lavage fluid after biopsy were histologically identified as sulfur granules, a classic pathological indication of actinomycosis. This confirmed the diagnosis of pulmonary actinomycosis. The patient was treated with penicillin, and the opacities in the right lower lobe subsided.     

A Lower Irradiation Dose of 308 nm Monochromatic Excimer Light Might Be Sufficient for Vitiligo Treatment: A Novel Insight Gained from In Vitro and In Vivo Analyses

A 308 nm monochromatic excimer light (MEL) is widely used to treat patients with vitiligo. However, dose optimization still needs to be clarified. This study aimed to obtain objective evidence regarding various doses of MEL irradiation, induced cell level changes in vitro, and skin level alterations in vivo. Cultured human keratinocytes were irradiated with MEL using various doses. After irradiation at low doses, stem cell factor, endothelin-1, and glycoprotein nonmetastatic melanoma protein B, factors that activate and protect melanocytes, were found to be significantly elevated in keratinocytes. After irradiation using medium and high doses, inflammatory cytokines were induced. The amount of ATP released and the level of inflammasome activation, which are known to be related to interleukin-1β activation, were also increased. The back skin of guinea pigs and mice were irradiated with MEL at varying doses. After irradiation, an increase of epidermal melanin and epidermal melanocytes was confirmed, using the minimal erythemal dose or less. In rhododendrol-induced leukoderma guinea pigs, a much lower dose of MEL irradiation was effective, when compared with the effective dose for control guinea pigs. Our results suggest that a lower irradiation dose of MEL might be sufficient and more suitable for repigmentation in vitiligo treatment.     

Peak load forecasting using multiple-year data with trend data processing techniques

This paper presents a regression-based daily peak load forecasting method using multiple-year data with trend cancellation and trend estimation techniques. Daily peak load heavily depends on daytime temperature and is influenced by the other weather factors such as humidity. Since the characteristic of the load is varying, peak loads just before a forecasting day are more significant for the forecasting. The regression model can represent relationships between these weather factors and peak loads. However, the forecasting model is sometimes not adequate for precise load forecasting. The regression model is well matched with the late data, but the model causes large forecasting errors in transitional seasons because of seasonal change of load characteristics. In order to forecast precisely through a year, a method of using seasonal or whole year data from past years is proposed. In this paper, two kinds of trend data processing techniques are described. The first is trend cancellation. The second is trend estimation. The trend cancellation technique removes annual load growth by means of division or subtraction processes with morning load on the forecasting day. The trend estimation technique estimates the trend between the forecasting year's load and the past year's load by using the variable transformation techniques. The performance of both techniques, verified with simulations on actual load data, is also described. © 1998 Scripta Technica, Electr Eng Jpn, 124(1): 7–16, 1998     

Asymmetrical modulation and overmodulation of parallel-connected NPC-PWM inverters

The neutral point clamped (NPC)-PWM inverter has significant advantages, such as its ability to operate motors with nearly sinusoidal current waveforms. For this reason, in larger-capacity inverter systems, NPC-PWM inverters using GTOs and the like have been put into practical use, because of great advantages to large-capacity ac motor drives, such as lower ripple currents and higher output voltages. With the spread of applications, inverters of still larger capacity are expected. However, since the capacities of such switching devices are insufficient, a certain technique and controlling method are proposed for the parallel connection of NPC inverters. In this paper, conventional modulation techniques are extended to improve the inverter characteristics; asymmetrical modulation and overmodulation techniques are introduced for the parallel-connected NPC inverter. In the proposed modulation strategies, the waveforms become more complicated, so that it is difficult to analyze the output waveforms. For those waveforms, an analytical waveform analysis method using the switching function is proposed. With such a method, the physical meaning of harmonic generation can be realized to some extent. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(2): 49–58, 1997     

Improvement in heat transfer performance by employing unique screen inserts in a horizontal heat pipe under small heat flux conditions

Two kinds of screen mesh inserts were produced with unique cross-sectional shapes (NW2 and NW3) to improve heat transfer in a horizontal evaporating tube under small heat flux conditions. These inserts were expected to supply liquid from the thick bottom layer to the upper (top) part of a heated horizontal round tube, which is the most difficult part to wet. In the present work, heat transfer performances were investigated experimentally by using a horizontal heat pipe with a visual observation capability. The experimental results showed that NW2 and NW3 worked well if the heat flux was less than 8 kW/m². This improvement was confirmed by comparison with both the data for an ordinary screen-mesh wick and calculated results based on an analytical model. © 1998 Scripta Technica, Heat Trans Jpn Res, 26(8): 529–540, 1997     

Microstructure of TiO2 and ZnO Films Fabricated by the Sol-Gel Method

Titanium dioxide and zinc oxide films were fabricated by spin-on and dip-coating methods. Both types of films exhibited columnar grains when the single coating was thin, ∼10 nm. The columnar TiO₂ films were dense, as confirmed by their density values calculated from the refractive index and TEM results. The addition of Al cations into the ZnO suppressed grain growth, because Zn had a lower diffusivity in the doped films. The doped ZnO films had nearly the same electrical resistivity as that of the undoped films.     

Primary biliary cirrhosis: symptoms, laboratory data and diagnosis

The most frequent and important symptoms in primary biliary cirrhosis (PBC) are pruritus and jaundice. In the majority, jaundice appears within one half to two years of onset of pruritus. Xanthoma, bone change and sicca syndrome are often observed. The recent increase in number of asymptomatic PBC is the result of progagation of medical examination. In the biochemical tests, elevation of the biliary enzymes, such as ALP and gamma-GTP, is characteristic, as well as, a high level of serum IgM. Serum bilirubin values are gradually raised along with the clinical course of the disease. Positive antimitochondrial antibody (AMA) is the most valuable immunological finding for the diagnosis of PBC. Anti-pyruvate dehydrogenase complex E2 component E2 has the same significance as AMA. Diagnostic criteria si shown in this paper.