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Poor air quality arises by and large from inadequate ventilation and presence of contaminants. In particular to hospital environments, it exercises direct and significant influence over infections occurrence. The purpose of this paper is to research, through computational fluid dynamics, how ceiling (four-way supply) and sidewall (conventional high supply) inlets systems, as well as outlet (exhaust) positioning, effect air motion and distribution in operating rooms. By the assistance of numerical modeling, four alternative scenarios of a operating room were investigated, maintaining flow rates and varying inlet system and outlet position. The results are presented in terms of velocity vectors and temperatures, which were compared to the experimental data available. Subsequently, a qualitative analysis regarding conformity to sanitary requirements was conducted.

Area densities of Au/Ni/Cu layers on a Cr-coated quartz substrate were characterized to certify a multiple-metal-layer certified reference material (NMIJ CRM5208-a) that is intended for use in the analysis of the layer area density and the thickness by an X-ray fluorescence spectrometer. The area densities of Au/Ni/Cu layers were calculated from layer mass amounts and area. The layer mass amounts were determined by using wet chemical analyses, namely inductively coupled plasma mass spectrometry (ICP-MS), isotope-dilution (ID-) ICP-MS, and inductively coupled plasma optical emission spectrometry (ICP-OES) after dissolving the layers with diluted mixture of HCl and HNO3 (1:1, v/v). Analytical results of the layer mass amounts obtained by the methods agreed well with each another within their uncertainty ranges. The area of the layer was determined by using a high-resolution optical scanner calibrated by Japan Calibration Service System (JCSS) standard scales. The property values of area density were 1.84 ± 0.05 μg/mm2 for Au, 8.69 ± 0.17 μg/mm2 for Ni, and 8.80 ± 0.14 μg/mm2 for Cu (mean ± expanded uncertainty, coverage factor k = 2). In order to assess the reliability of these values, the density of each metal layer calculated from the property values of the area density and layer thickness measured by using a scanning electron microscope were compared with available literature values and good agreement between the observed values and values obtained in previous studies.

This work deals with the development of a numerical technique to simulate 3D complex turbulent free surface flows. This technique is based on the finite-difference GENSMAC methodology coupled with high Reynolds $$\kappa -\varepsilon$$ turbulence model and the ADBQUICKEST upwind scheme to deal with the advective terms. The computations are performed using the 3D version of the Freeflow simulation system, in which the effectiveness of the numerical technique is analyzed for the dam-break flow and a turbulent jet impinging orthogonally onto a flat surface. The numerical results are compared with existing analytical and experimental data. To demonstrate applicability of the Freeflow-3D simulation system for solving complex free surface flows at high Reynolds numbers, a case of the fluid–structure interaction was simulated.

In this paper, we present a numerical technique for the simulation of two-dimensional incompressible turbulent flows. In particular, the performance of the realizable Reynolds stress algebraic equation model and the high-order polynomial upwind scheme, TOPUS, is assessed for free surface incompressible turbulent flows. The Reynolds averaged Navier–Stokes equations and continuity equations are solved using the finite difference methodology on a staggered grid system. The numerical method is investigated by solving two free surface fluid flow problems, namely, a turbulent free jet impinging onto a flat surface and a broken dam. The method is then applied to simulate a sluice gate and a horizontal jet penetrating a quiescent fluid from an entry port beneath the free surface.

The STJ array detectors with an effective detection area of 4 mm2, which consist of 100 Nb/Al-AlOx/Al/Nb junctions with a size of 200×200 μm, have been fabricated. In order to improve the reproducibility of the STJ array fabrication, we investigated a correlation between the junction surface structures and the leakage currents. It has been found that the junctions near the fringe of the array detectors have a step of about 5 nm at the middle of the array detector, of which leakage currents are considerably larger than 1 μA. The step structure was formed after the etching of the bottom Nb layer for complete separation of Nb/Al/AlOx/Al/Nb/Si. In case of the sputtered Nb/Al/Nb/Si multilayers without 1 nm-thick tunneling barrier, no stepped surface was observed even after the bottom Nb layer etching. Therefore, it is apparent that the 5 nm step structure is a cause of the large leakage currents. We solved the step-fringe problem by a kind of extra patterning along the fringe of the array or lift-off patterning of the Nb/Al multilayers. It is concluded that the number of the junctions with the step structure depends on a slight difference in film deposition or etching conditions.

We investigated the ozone oxidation characteristics on a hydrogen-terminated Si substrate. A high-concentration ozone gas generator with an ozone condensation unit was specially designed and assembled for this study. During the oxidation by ozone with the concentration of 25 vol.% in the temperature range from 340°C to 625°C at 8 Torr (1.1 kPa), the formed oxide film thickness increased with oxidation time in accordance with the parabolic law, which suggests a diffusion-controlled step, while the oxidation by pure oxygen attained saturated states within 3 min of initiating oxidation. The activation energy for parabolic constants in the ozone oxidation was determined to be 0.52 eV. This value is much smaller than the activation energy for dry oxidation with oxygen, while it is almost the same as that in the plasma oxidation with the mixture of rare gas and oxygen. Moreover, the quality of the ozone oxidation film was evaluated by estimating the amount of suboxides (Si3++Si2++Si+) using x-ray photoelectron spectroscopy (XPS) analysis and the compressive stress using Fourier transform infrared (FT-IR) spectroscopic analysis. Both results showed that the quality of film subjected to ozone oxidation at 500°C is equal or superior to that of the film subjected to pyrogenic oxidation at 750°C in spite of the faster oxidation rate, and thus, the significant advantages of ozone oxidation at low oxidation temperatures could be confirmed.

We have investigated the characteristics of silicon oxidation by concentrated ozone gas through the comparison of the oxidation by oxygen molecules. A sophisticated high-concentration ozone generator, which exploits the ozone/oxygen gas separation technique with silica gel, has been developed for the study. The generator can continuously supply ozone-oxygen mixtures with ozone concentrations up to 30 at.% at one atmospheric pressure. Ozone gas with a concentration of 25 at.% from the generator formed SiO2 films as thick as 2 nm and 6 nm on Si for a 30 min. exposure at 200°C and 600°C, respectively. On the other hand, oxygen gas by itself could form SiO2 films with only 1 nm and 3 nm thickness, respectively, at the same conditions. Moreover, in the oxide film formation at 600°C, the oxide film growth by ozone was proceeded with an oxidation time in excess of 240 min., while it saturated within very short time in the oxidation by oxygen. These phenomena verify the strong oxidation power of ozone. In addition, we confirmed that the growth rate of the silicon oxide with ozone dramatically changed when the substrate temperature was over 500°C, and this suggested the change of oxidation mechanism at this point. However, such a characteristic was not found in oxidation with oxygen.

A rare case of traumatic injury of the distal descending aorta associated with thoracic spine injury is reported. A 21-year-old man was admitted after a traffic accident. Thoracic CT and angiography demonstrated a false aneurysm of the distal descending aorta and a compression fracture of the eleventh thoracic vertebra. At emergency surgery, a transverse linear tear at the level of the aortic hiatus was confirmed and repaired.

We prepared an atomically flat silicon substrate which had a step-terrace structure and observed the topography of the ozone-oxidized surface to clarify whether homogeneous oxidation occurs with ozone. The oxide was formed with high-concentration ozone gas with a thickness of 2.5nm at a temperature of 350°C. The oxide surface still maintained the same step-terrace structure as observed before oxidation, which revealed that ozone-oxidation occurs layer-by-layer and produces an atomically flat oxide. XPS and MEIS analyses show that the stoichiometry of ozone oxide grown at 350°C is the same as that of an oxide grown thermally at 750°C.

A high-concentration ozone generator operating at atmospheric pressure has been developed for fabrication of ultra thin silicon oxide films. The generator can supply atmospheric pressure of ozone jet with ozone concentration up to 80 vol%. The ozone jet is generated by desorbing ozone at nearbyn room temperature, which has been condensed on silica-gel by passing ozone/oxygen mixture gas from a commercial ozonizer at a low temperature (2 film as thick as 3.3 nm grew on a Si surface after 60 min exposure at 375°C. The density of the film was equivalent to that of the film formed by a conventional thermal oxidation process, judging from etching rate with dilute HF solution.

The oxidation of H/Si(100) and H/Si(111) with high concentration ozone gas was investigated with X-ray photoelectron spectroscopy(XPS). The ozone oxidation of partially hydride-covered surface was observed. The hydrogen termination reduced the rate of oxygen insertion into silicon backbond. The reduction of oxygen insertion rate by the H-termination for H/Si(100) was larger than that for HSi(111). The dissociation rate of ozone molecule on H/Si was estimated to be ≃0.2 with a directional mass analyzer.

The oxidation of Si(111) and Si(100) surfaces with the high-purity ozone(more than 98 mole %) was investigated with X-ray photoelectron spectroscopy (XPS). Thin oxide less than 3nm thickens was formed in an experimental chamber and the results showed that ozone oxidizes the (111) surface faster than (100) surface. Ozone does not show the temperature dependence on oxidation within the temperature range of 250–500 degree C for both (111) and (100) surfaces. Ozone proceeds the oxide formation at 700 degree C where oxygen does not proceed oxide formation rapidly.

IL-10 is an anti-inflammatory cytokine. Its blood concentration is said to rise in response to various invasive stimuli together with inflammatory cytokines. Studies on the effects of hemorrhagic shock on cytokine production are few, and they refer mainly to inflammatory cytokines. In this study, IL-10 was measured in patients with hemorrhagic shock. Its transition over time and its relation to inflammatory cytokines was investigated. The subjects were four patients in hemorrhagic shock due to non-trauma and 17 patients in hemorrhagic shock due to trauma. Their average age was 40.1 years. The APACHE-II score for the trauma subjects was 18.6 and 25.8 for non-trauma, with an average of 20.0 for all subjects. The average ISS of the trauma subjects was 26.1. A positive correlation was found between IL-10 and IL-6 (r = 0.777). IL-6 is generally regarded as reflecting the severity of a patient's condition, and as a consequence of our findings, IL-10 should also be useful as a marker of patient severity. Changes in cytokine levels were assessed in relation to the cause of hemorrhage. IL-6 and IL-10 levels were high in hemorrhagic shock due to trauma but did not rise remarkably in shock due to non-trauma, indicating that tissue injury is an important factor in causing high cytokine levels.