In situ measurements were carried out to quantify montmorillonite dissolution rates at a compaction pressure ranging from 0.04 to 10.00 MPa and temperature of 70°C in 0.3 M NaOH solution (pH 12.1 at 70°C) using vertical scanning interferometry (VSI) and an auto-compaction cell. Ex situ measurements of the reacted samples using atomic force microscopy (AFM) were performed to quantify the ratio of edge surface area (ESA) to total surface area (TSA) (XESA = ESA/TSA). Accordingly, the actual ESA for the montmorillonite examined by in situ VSI could be estimated. The XESA value increases as a function of run duration or compaction pressure. At atmospheric pressure, XESA is approximately 0.0054 and converges to ∼0.0107 at 10 MPa, An expression that relates reactive surface area and montmorillonite compaction (XESA/XESA initial = kXESA, k: variable factor) is kXESA = 1.0 + 0.64628 P0.1527 where P is in MPa. Using the calculated XESA, dissolution rates from the in situ VSI measurements are obtained. The early dissolution (<1500 min) at less compaction pressure tends to show faster rates (>1.0 × 10-11 mol/m2/s) than that at higher compaction pressure. The rates after >1500 min are slower, with values of less than 3×6 10-12 mol/m2/s, but there is no significant dependency on the density in the range from 1.0 to 1.7 Mg/m3. These observed rates for compacted montmorillonite are two-orders of magnitude slower (2.63×10-13 mol/m2/s) than dissolution rates in the suspended state.

In many countries, compacted bentonite is a candidate engineering barrier material for safe disposal of high-level radioactive waste. The Swedish Nuclear Fuel and Waste Management Company (SKB) set up an in situ experiment (the ABM project) to compare the stability of different bentonites under the conditions of exposure to an iron source and to elevated temperature (up to 130°C) at the Äspö Hard Rock Laboratory, Sweden. Results for the Japanese bentonite (Kunigel V1) are summarized in the present study.

Mineralogical investigation using X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) suggested no transformation of smectite or neoformed clay phases. However, a distinct change in exchangeable cations of smectite was indicated (i.e. from Na type to Fe type and/or Ca type) in the bentonite in the vicinity of the steel heater.

Measurements of hydraulic conductivity and swelling properties suggest that no significant changes occurred in the bentonite even in the vicinity of the steel heater. This is attributed to the limited portion of the bentonite affected by the iron–bentonite interactions and the incomplete ion-exchange reactions. The methylene blue cation exchange capacity and the determination of the exchangeable cations showed that the lateral distribution for these parameters was constant. However, the total exchangeable cation population has changed significantly compared to the initial sample.

We present recent observation results of Sgr A* at millimeter obtained with VLBI arrays in Korea and Japan.

7 mm monitoring of Sgr A* is part of our AGN large project. The results at 7 epochs during 2013-2014, including high resolution maps, flux density and two-dimensional size measurements are presented. The source shows no significant variation in flux and structure related to the G2 encounter in 2014. According to recent MHD simulations by kawashima et al., flux and magnetic field energy can be expected to increase several years after the encounter; We will keep our monitoring in order to test this prediction.

Astrometric observations of Sgr A* were performed in 2015 at 7 and 3.5 millimeter simultaneously. Source-frequency phase referencing was applied and a combined ”core-shift” of Sgr A* and a nearby calibrator was measured. Future observations and analysis are necessary to determine the core-shift in each source.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

We present VLBI maps of the 6.7 GHz methanol maser emission in 32 sources obtained using the Japanese VLBI Network (JVN) and the East-Asian VLBI Network (EAVN). All of the observed sources provide new VLBI maps, and the spatial morphologies have been classified into five categories similar to the results obtained from European VLBI Network observations (Bartkiewicz et al. 2009). The 32 methanol sources are being monitored to measure the relative proper motions of the methanol maser spots.

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

The sheet resistance and sheet carrier concentration for Si ion implanted GaN have been investigated as a function of Si ion dosages and ion's energy using van der Pauw method and Hall effect measurement. Si ion implanted GaN is annealed at 1200 °C for 10 sec in N2 gas flow with 50 nm-thick SiNx cap layer to avoid dissociation of GaN. For Si ion energy of 30 keV, the sheet resistance is decreased from 103 to 56 ohm/sq. for the dose ranging from 1 × 1014 to 2 × 1015/cm2. For the Si dose larger than 2 × 1015/cm2, the sheet carrier concentration is saturated around 1 ×s 1015/cm2. Si ion implanted GaN with energy of 50, 80, and 120 keV at a dose of 2 × 1015/cm2 also reveal the sheet carrier concentration of about 1 × 1015/cm2 with the decrease of electron mobility. It is suggested that the implanted Si donors are strongly compensated by the residual implantation-induced defects.

Summary

Background and objectives: Sodium bicarbonate is the most physiological alkalinizing agent. The effect of a new bicarbonated Ringer's solution (BRS) containing Mg2+, on metabolic acidosis and serum magnesium abnormality were evaluated and compared with those of acetated Ringer's (ARS), lactated Ringer's (LRS) and Ringer's (RS) solutions in an experimental haemorrhagic shock model with dogs. Methods: Animals were randomly divided into six groups (n = 6 in each group), a sham-operated group, an operated group without infusion, and 4 operated groups with infusion (BRS, ARS, LRS and RS groups). Each RS was intravenously administered at 60 mL kg−1 h−1 for 1.5 h. Arterial blood gases, plasma electrolytes and cardiovascular parameters were analysed. Results: BRS significantly improved blood base excess values, which were decreased by blood-letting, faster and more markedly than did LRS and RS (BRS −6.3 ± 0.5 mEq L−1; LRS −9.2 ± 1.1 mEq L−1; RS −12.4 ± 1.0 mEq L−1 at the end of infusion). The alkalinizing effect of BRS tended to be better than that of ARS but not significantly so. The serum Mg2+ concentration was well-maintained by BRS as compared to other RS (BRS 1.5 ± 0.0 mg dL−1; ARS 1.2 ± 0.0 mg dL−1; LRS 1.1 ± 0.0 mg dL−1; RS 1.3 ± 0.1 mg dL−1, at the end of infusion). Conclusions: These results suggest that BRS is a suitable perioperative solution for metabolic acidosis and serum electrolyte balance among RS tested.

Summary

Background and objective: The effects of bicarbonated Ringer's solution were evaluated and compared with those of acetated Ringer's, lactated Ringer's and Ringer's solutions in partially hepatectomized rabbits. Method: Animals were randomly divided into six groups (n = 6 in each group): a sham-operated group, an operated group without infusion, and four operated groups with infusions of each of the four Ringer's solutions. Each Ringer's solution was intravenously administered at 40 mL kg−1 h−1 for 1.5 h. Arterial blood gases, plasma magnesium concentrations and cardiovascular parameters were analysed. Results: The partial hepatectomy-induced decrement of base excess was inhibited by bicarbonated Ringer's solution more remarkably than by either lactated or plain solutions (P < 0.01). The alkalinizing effect of bicarbonated Ringer's solution tended to be more marked than that of the acetated solution but not significantly so. Plasma magnesium concentrations were well maintained by bicarbonated solution as compared to the other solutions (P < 0.01). Conclusions: These results suggest that bicarbonated Ringer's solution is the most suitable perioperative solution for metabolic acidosis and plasma electrolyte balance among the Ringer's solutions tested.

Summary

Background and objective: Isoflurane is commonly used for neurosurgery but the effects of sevoflurane on human cerebral blood flow and cerebral metabolic rate of oxygen have not been fully evaluated. We therefore assessed the effects of sevoflurane and isoflurane on global cerebral blood flow and cerebral metabolic rate of oxygen in patients without noxious stimuli or neurological disorders.

Methods: General anaesthesia was induced with midazolam (0.2 mg kg−1) and fentanyl (5 μg kg−1) in 20 ASA I patients undergoing knee joint endoscopic surgery. Epidural anaesthesia was also performed to avoid noxious stimuli during surgery. Cerebral blood flow and cerebral arteriovenous oxygen content difference was measured using the Kety–Schmidt method with 15% nitrous oxide as a tracer before and after administration of either sevoflurane or isoflurane (1.5 minimum alveolar concentration, 60 min) and cerebral metabolic rate of oxygen was then calculated.

Results: Sevoflurane and isoflurane both increased cerebral blood flow (17%, P < 0.05; 25%, P < 0.05, respectively) and decreased cerebral metabolic rate of oxygen (26%, P < 0.01; 38%, P < 0.01, respectively). There were no significant differences in cerebral blood flow and cerebral metabolic rate of oxygen between sevoflurane and isoflurane.

Conclusions: Sevoflurane and isoflurane similarly increased cerebral blood flow and decreased cerebral metabolic rate of oxygen in human beings anaesthetized with midazolam and fentanyl.

Summary

Background and objective: The mechanism underlying stable cuff pressure in the Brandt rediffusion endotracheal tube during anaesthesia with nitrous oxide is not fully understood. The present study assessed changes in gas concentrations in the cuff during and after nitrous oxide anaesthesia.

Methods: The pressure of an air-filled Brandt endotracheal tube cuff was measured; anaesthesia was maintained with nitrous oxide 67% and oxygen 33% for 6 h in the Continuous Group; oxygen was substituted for nitrous oxide after 3 h of nitrous oxide anaesthesia in the Discontinuous Group (n = 8 for each). In some other patients, the study was terminated at 90, 180, 270 and 360 min (n = 8 for each). Gas concentrations in the cuff were measured at the end of the study.

Results: Cuff pressures increased slightly during the first 180 min of anaesthesia (P < 0.001). Thereafter, the cuff pressure did not change significantly in the Control Group but decreased in the Discontinuous Group (P < 0.001); there was a significant difference between the two groups (P < 0.0001). Cuff pressure never exceeded 22 mmHg and there were no air leaks in either group during the 6 h anaesthesia. Nitrous oxide concentrations in the cuff were 11.3 ± 2.6% and 2.6 ± 0.8% in the Control Group and Discontinuous Groups, respectively; however, changes in carbon dioxide and oxygen concentrations in the cuff were within approximately 1%.

Conclusions: Small changes in the nitrous oxide concentration in the cuff contribute to a stable cuff pressure in the Brandt rediffusion system, but changes in carbon dioxide or oxygen concentrations have little effect.

Summary

Background and objective: Phosphodiesterase-III inhibitors and dobutamine effectively improve cardiac function in patients with cardiac failure, but they are limited by possible hypotensive effects. We tested the hypothesis that dopamine contributes to stabilizing milrinone-induced haemodynamic changes.

Methods: Nine patients undergoing major surgery were anaesthetized using nitrous oxide and oxygen supplemented with isoflurane 1–2%. After baseline haemodynamics were recorded, milrinone (25 or 50 μg kg−1) was administered over 10 min, followed by a continuous infusion (0.5 μg kg−1 min−1). The second set of haemodynamic values was measured 50 min after beginning the continuous infusion of milrinone. Dopamine (4 μg kg−1 min−1) was then administered with milrinone.

Results: Milrinone significantly increased the heart rate from 81 ± 8 to 102 ± 16 beats min−1, but it decreased the mean arterial pressure from 83 ± 10 to 66 ± 10 mmHg and systemic vascular resistance (P < 0.05 for each). The pulmonary capillary wedge pressure, cardiac index and pulmonary vascular resistance did not change significantly. The addition of dopamine to the milrinone infusion significantly decreased the heart rate (94 ± 12 beats min−1) and increased the mean arterial pressure (82 ± 11 mmHg). Dopamine and milrinone, but not milrinone alone, significantly increased the cardiac index and the rate–pressure product.

Conclusions: The combination regimen of milrinone and dopamine improved cardiac function, and changes in heart rate and mean arterial pressure induced by milrinone were attenuated by dopamine. The results suggest that a combination regimen of milrinone and dopamine rather than milrinone alone should be used to maintain arterial pressure.

Terahertz (THz) time-domain spectroscopy (TDS) has been used to study far infrared absorption spectra of chloroform confined within nanoporous glasses of various pore sizes. Intermolecular interactions and dynamics in the confined system are discussed.

Cu(In,Ga)Se2(CIGS) thin films were prepared at substrate temperatures of 350 to 500 °C. The (In,Ga)2Se2 precursor layers were deposited on Mo coated soda-lime glass and then exposed to Cu and Se fluxes to form CIGS films. The surface composition was probed by a real-time composition monitoring method. The CIGS films were characterized by x-ray diffraction, energy dispersive x-ray spectroscopy, secondary ion mass spectroscopy, and atomic force microscopy. The transient formation of a Cu–Se phase with a high thermal emissivity was observed during the deposition of Cu and Se at a substrate temperature of 350 °C. Faster diffusion of In than Ga from the (In,Ga)2Se3 precursor to the newly formed CIGS layer was observed. A growth model for CIGS films during the deposition of Cu and Se onto (In,Ga)2Se3 precursor is proposed. A solar cell using a CIGS film prepared at about 350 °C showed an efficiency of 12.4%.

We investigated the effect of a small dose of midazolam, ketamine, droperidol or lidocaine on the propofol dose required for hypnosis during induction of general anaesthesia. These drugs were randomly administered to 100 patients about to undergo scheduled surgery. Propofol was then infused at a rate of 250 μg kg−1 min−1 and the hypnotic dose to produce hypnosis was evaluated. Midazolam (20 μg kg−1) and droperidol (20 μg kg−1) significantly reduced the mean hypnotic dose of propofol (mean) S.D.) compared with the placebo (43.7 ± 17.8 mg, 61.9 ± 10.6 mg and 72.5 ± 27.7 mg after pretreatment with midazolam, droperidol and placebo, respectively), whereas ketamine (0.1 mg kg−1) and lidocaine (1 mg kg−1) did not significantly affect the hypnotic dose of propofol (63.1 ± 25.6 mg and 65.1 ± 24.8 mg, respectively). Only midazolam when compared with saline administration, (176 ± 66s and 298 ± 126s, respectively), shortened the time to achieve hypnosis. The changes in blood pressure (non-invasive) and heart rate were not significantly different in all groups during the induction of anaesthesia and oro-tracheal intubation. These results raise the possibility that new combinations of central nervous system drugs, such as droperidol and propofol, have a potential to reduce the dose of intravenous anaesthetics, including propofol, that produce hypnosis without significant adverse effects.

Growth of Cu(In,Ga)Se2 (CIGS) films from In–Ga–Se precursors was characterized by scanning Auger electron spectroscopy (SAES), secondary ion mass spectroscopy (SIMS), x-ray diffraction, scanning electron microscopy, and transmission electron microscopy (TEM). In–Ga–Se precursor layers were deposited on Mo-coated soda-lime glass, and then the layers were exposed to Cu and Se fluxes to form CIGS films. The SIMS and SAES analyses showed a homogeneous distribution of Cu throughout the CIGS films during the deposition of Cu and Se. The phase changes observed in the CIGS films during the deposition of Cu and Se on the In–Ga–Se precursor films were as follows: (In,Ga)2Se3 →[Cu(In,Ga)5Se8] →Cu(In,Ga)3Se5 →Cu(In,Ga)Se2. The grain size increased from the submicron grains of the (In,Ga)2Se3 precursor film to several micrometers in the stoichiometric Cu(In,Ga)Se2 film. A growth model of CIGS crystals is introduced on the basis of the results of TEM observations. CIGS crystals are mainly grown under (In,Ga)-rich conditions in the preparation from In–Ga–Se precursor films.

Ultrathin films of perovskite PbTiO3, 10–100nm thick, were epitaxially grown on miscut (001)SrTiO3 substrate by rf-magnetron sputtering at 600°C. The electron microscope and high resolution x-ray diffraction analysis suggested the evidence of epitaxial growth of (001)PbTiO3/(001)SrTiO3 with three dimensional crystal orientation. The stoichiometric film shows extremely smooth surface with the surface roughness less than 3nm. Deposition on a miscut substrate under stoichiometric conditions is essential to make continuous thin films of single crystal perovskite PbTiO3.

To examine the non-linear oscillation and period change of white dwarf variables, ZZ Psc is discussed observationally. As a result of data reduction we found two major periods, 680 seconds and 860 seconds, but could not find chaotic behavior of ZZ Psc.

Visual light curves of some Mira and semiregular variable stars are analyzed to search for their chaotic and statistical behaviour. Discussion are also given.