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The target vessel, which enclosing liquid mercury, for the pulsed spallation neutron source at the J-PARC is severely damaged by cavitation caused by proton beam-induce pressure waves in mercury. To mitigate the cavitation damage, we adopted a double-walled structure with a narrow channel for the mercury at the beam window of the target vessel. The narrow channel disturbs the growth of cavitation bubbles due to the pressure gradient. In addition, gas microbubbles are injected into the mercury to suppress the pressure waves. After finishing service operation, the front end of the target vessel was cut out to inspect the effect of those cavitation damage mitigation technologies on the interior surface. The damage depth of the cutout specimens for the original design type and double-walled target vessels were quantitatively investigated by the replica method. The results showed that the double-walled target facing mercury with gas microbubbles operate 1812 MWh for an average power of 434 kW is equivalent to the damage of original design target operated 1048 MWh for average power of 181 kW. The erosion depth due to cavitation in the narrow channel is clearly smaller than on the wall facing bubbly mercury.

Neutron flux per pulse reached world record at neutron source in Japan Proton Accelerator Research Complex (J-PARC). In the J-PARC, mercury target system is used as a spallation neutron source. A t...

A mercury target vessel made of 316L SS is damaged due to the cavitation caused by the pressure waves in mercury. Cavitation damage reduces the structural integrity of the target front, called "beam window", being major factor to determine the lifetime of target vessel. Aiming at mitigating the cavitation damage by faster mercury flow in narrow channel, we employed a target vessel with a double-walled structure at the beam window along with a gas microbubbles injection. After operating the double-walled target vessel with a beam power of 300 to 500 kW, we cut out the beam window using an annular cutter to examine the damage inside it, and found that damages with maximum pit depth of approximately 25 $\mu$m distributed in a belt on the specimen facing narrow channel. Furthermore, numerical simulation result showed that the distribution of negative pressure period from beam injection to 1 ms was correlated with the damage distribution in the narrow channel. It was suggested that the cavitation induced by relatively short negative pressure period contributed to the damage formation., J-PARCの核破砕中性子源の水銀ターゲット容器(SUS316L製)は、ビーム窓と呼ばれる厚さ3mmの先端部分が、陽子線励起圧力波よるキャビテーションにより壊食損傷する。この損傷は容器の構造健全性を低下させ、容器の寿命の決定因子となっている。我々は、2014年からキャビテーション損傷及びそれを誘発する圧力波を低減するために、気泡注入に加えて狭隘流路を設置することで、ビーム窓の水銀流速を速める2重壁構造を採用し、300$\sim$500kWの強度で運転を行った。使用済みの容器を切断し、内壁を観察した結果、狭隘流路の内側で最大深さ約25$\mu$mの帯状の損傷が観測された。この原因を調べるために、負圧の持続時間に着目した圧力波伝ぱ解析を実施した結果、ビーム入射直後から1msまでに生じる負圧の持続する時間をマッピングした結果と、形成された損傷の分布がよく対応しており、比較的短時間の負圧によって生じるキャビテーションが損傷形成に寄与していることを示唆した。

The spallation neutron source at the Japan Proton Accelerator Research Complex (J-PARC) mercury target vessel is used for various materials science studies, work is underway to achieve stable operation at 1 MW. This is very important for enhancing the structural integrity and durability of the target vessel, which is being developed for 1 MW operation. In the present study, to reduce thermal stress and relax stress concentrations more effectively in the existing target vessel in J-PARC, an optimization approach called the Taguchi method (TM) is applied to thermo-mechanical analysis. The ribs and their relative parameters, as well as the thickness of the mercury vessel and shrouds, were selected as important design parameters for this investigation. According to the analytical results of 18 model types designed using the TM, the optimal design was determined. It is characterized by discrete ribs and a thicker vessel wall than the current design. The maximum thermal stresses in the mercury vessel and the outer shroud were reduced by 14% and 15%, respectively. Furthermore, it was indicated that variations in rib width, left/right rib intervals, and shroud thickness could influence the maximum thermal stress performance. It is therefore concluded that the TM was useful for optimizing the structure of the target vessel and to reduce the thermal stress in a small number of calculation cases.

A silver-indium-cadmium (Ag-In-Cd, or AIC) alloy with a 1 eV high neutron cut-off energy was originaly developed as a decoupler to provide a narrow neutron pulse width with a short tail for the J-PARC 1-MW short-pulsed spallation neutron source. As a result of later studies, gold (Au) was chosen as a substitute for Ag for the production of spare decoupled moderators and reflector in order to reduce residual radioactivity thus easing handling and disposal of the spent moderator and reflector. The decoupler material Au-In-Cd (AuIC) was therefore investigated and developed. To implement it into an actual moderator-reflector assembly many critical engineering issues needed to be resolved with regard to large-sized bonding between AuIC and aluminum alloy A5083 by the hot isostatic pressing process (HIP). The HIP process for AuIC and aluminum was investigated in terms of surface condition, size, and heat capacity. Implementation of an AuIC decoupler into a spare reflector assembly was successfuly achieved and will result in a remarkable reduction of radioactivity compared to AIC without sacrificing neutronic performance.

Mercury target vessel in the JSNS, which is made of 316L SS, is damaged owing to the pressure wave-induced cavitation resulting from the proton beam bombardment. The cavitation damage decreases the structural integrity of the target vessel and is currently a dominant factor to decide the service life in compared with the radiation damage. Injecting microbubbles into mercury is one of the prospective techniques to mitigate the pressure waves and cavitation damage. In the JSNS, a microbubble generator with a gas circulation system was installed and has been operated since October 2012. The effects of microbubble injection into mercury on pressure wave mitigation were studied using a laser Doppler vibrometer. The result showed that the vibrational velocity of the target vessel is clearly reduced according to the increase of void fraction. An average peak vibrational velocity under 340 kW operation with the void fraction of 0.1\% was reduced to 1/4 of that without injecting microbubbles., J-PARCの核破砕中性子源(JSNS)水銀ターゲット容器は、陽子線入射励起圧力波により励起されるキャビテーションによる損傷を受ける。キャビテーションによる損傷は、容器の構造健全性を低下させるため現在のところ容器の交換寿命を決める支配因子となっている。圧力波及びキャビテーションによる損傷を低減するためには、水銀中にガスマイクロバブルを注入することが効果的な手法である。JSNSでは、ガスマイクロバブルを注入するためのシステムを2012年10月に設置し、レーザードップラー振動計を用いて容器の振動をモニタリングすることによって水銀中へのバブル注入の効果をした。その結果、振動速度は気泡注入量の増加に伴って減少することを確認した。また長期間の運転では、気泡注入によって平均でバブル注入無しの1/4程度の振動速度を維持した。

AIM: To investigate the occurrence and severity of pruritus in chronic hepatitis C patients treated with or without interferon (IFN) therapy. METHODS: A total of 89 patients with chronic hepatitis C and 55 control (non-hepatitis) patients were asked to rate their experience of diurnal and nocturnal pruritus in the preceding week using a visual analogue scale (VAS) and a five-point scale, respectively. Blood samples were taken and serum thymus and activation-regulated chemokine (TARC) levels were measured by enzyme-linked immunosorbent assay. RESULTS: A significantly greater proportion of chronic hepatitis C patients experienced nocturnal pruritus compared with control (58.4% vs 5.5%, P < 0.0001). Chronic hepatitis C patients also had more severe pruritus compared with control patients, indicated by the higher mean VAS scores in both the IFN-treated and non-IFN-treated groups. In particular, patients who received combined peginterferon alfa-2b and ribavirin had significantly higher mean VAS scores than those receiving peginterferon alfa-2a or no IFN treatment. Serum TARC levels did not correlate with pruritus scores, and no significant differences in TARC levels were observed between the IFN-treated and non-IFN-treated groups. CONCLUSION: Patients with chronic hepatitis C experience pruritus more than those without. Serum TARC levels do not correlate with pruritus severity in chronic hepatitis C patients.

Microfluidics is a rapidly growing field in which small volumes of liquid are moved through channels in a large variety of applications. Fabricating such channels can be expensive. Here, we describe an inexpensive method for making 3D channels in fluidic chips by using a sacrificial template made of coated metal wire or metal tubes. A 3D template is embedded in polymer or glass and then dissolved, leaving channels in the chip, without the need for expensive instruments. By changing the mold, chips of various shapes can be made.

An off-gas processing system was installed in the J-PARC spallation neutron source to reduce radioactivity of xenon-127 and tritium contained in a helium cover gas in a surge tank of a mercury circulation system to obey the regulation by law. In addition to this role it has been utilized to a purging process before the target vessel replacement and an air-flow control procedure to minimize uncontrollable radioactivity release during the replacement. An standard and urgent model plans of the off-gas processing system operation were established indicating that 31 days were required at least to replace the target vessel.

In the present study, a sooting flame was formed in a reduced-pressure combustion chamber using the vitiated coflow burner with a premixed flame of methane and oxygen for the surrounding flame and premixed flame of toluene, methane and oxygen for the center flame. Collected soot samples were analyzed using the high performance liquid chromatography (HPLC) and a gas chromatography to determine the fullerene content of soot and the species of PAHs under various conditions. Effects of pressure and equivalence ratio to the formation of the PAHs and fullerenes and the branching mechanism between fullerene and soot were discussed. When the fullerene content in soot samples was relatively high, the fractions of anthracene and benzo [a] anthracene were relatively high. When the fullerene content in soot samples was relatively low, the fractions of phenanthrene, flouranthene and pyrene were relatively high. Under the same pressure condition, there was an optimal flow rate of toluene in the center flame for formation of C60 and C70 of which range became wider with the decrease of pressure condition.

A ceramic micro fabrication process has been developed for the 1-3 piezo-electric composites which is suitable for high frequency, wideband ultrasonic transducer. This process employs synchrotron radiation (SR) lithography and a micro molding process. This process realized an array of lead zirconate titanate (PZT) rods whose cross section is 25 microns. The material is expected to improve the resolution of the ultrasonic diagnosis, because composites can transmit a short ultrasonic pulse and have high sensitivity. In addition, when circular shape PZT rods is arranged at the apex of the regular triangle, the internal resonant mode became clear to be suppressed.

Double-differential cross sections (DDXs) have been measured for light-charged particle production in proton-induced reactions on 12C, 27Al, 58Ni, 90Zr, 197Au, and 209Bi at incident energies of 42 and 68 MeV. The measured DDXs for 12C, 27Al, and 58Ni are compared with the LA150 evaluation. Good overall agreement is found except for the (p, xd) reaction. The dependence of total yields of secondary charged-particles on target mass number is investigated.

For validation of calculation codes that are employed in the design of pulse spallation neutron source and accelerator driven system, spectrum of neutrons produced from a thick target plays an important role. However, appropriate experimental data were scarce for the incident energies higher than 0.8 GeV. In this study, the spectrum from a thick tungsten target was measured The experiment was carried out at the π2 beam line of the 12-GeV proton synchrotron at KEK. The tungsten target was bombarded by the 0.5- and 1.5-GeV secondary protons. Spectrum of neutrons was measured by the time-of-flight technique using organic scintillators of NE213, The calculated result with NMTC/JAM and MCNP-4A is compared with the measured data. It is found that the NMTC/JAM generally gives a good agreement with experiment. The NMTC/JAM, however, gives 50 % lower neutron flux in the energy region 20~80 MeV, which is consistent with the results in previous comparison of lead target. For the neutrons between 20 and 80 MeV, the c...

Background. Recently, careful attention has been paid to multiple risk factor syndromes, such as syndrome X, insulin-resistance syndrome, and visceral-fat syndrome, in terms of the development of coronary artery disease, which is also the major cause of death in hemodialysis patients. The purpose of this study was to evaluate the impact of visceral fat accumulation on these multiple risk factors in hemodialysis patients. Methods. Seventy-two stable outpatients (35 men, 37 women) participated in this study. After determination of the visceral fat area and the subcutaneous fat area by a computed tomography scanning technique, they were classified into two groups according to the value of the visceral fat area. Fasting blood samples were drawn for lipid and carbohydrate data. Results. The high-visceral fat group exhibited a significantly (1) higher insulin resistance index, (2) higher level of triglyceride, (3) lower level of high-density lipoprotein cholesterol, and (4) a higher atherogenic index, in comparison with the low-visceral fat group. Moreover, they had (5) a higher frequency of a history of coronary artery disease (33.3% vs 8.3%; P < 0.01). These findings are completely in accordance with the visceral fat syndrome. Conclusions. Visceral fat accumulation in hemodialysis patients has effects on lipid and carbohydrate metabolism, and it may increase the risk of coronary artery disease.

Effects of O2 gas on reaction mechanisms in the chemical vapor deposition (CVD) of (Ba, Sr)TiO3 [BST] film were studied by investigating the atomic incorporation rates of Ba, Sr, and Ti. The atomic incorporation rates were measured using an X-ray fluorescence method for BST film prepared for several molar source supply ratios with different O2 flow rates of 0.1, 0.5, and 1.0 slm. In the experiments, these rates were found to increase monotonically with increasing O2 flow rate in flux regions where incorporation reactions might be dominated kinetically. This suggested that the supplied O2 gas might affect the adsorption of film precursors onto the film surface in the CVD of BST. From the obtained experimental results, we proposed a CVD model, in which some precursors adsorbed on the film surface form adsorptive sites, and that successive precursors are adsorbed thereon. The supplied O2 gas contributes towards the formation of the adsorptive sites; the Ba and Sr precursors release their own oxygen and receive oxygen from the supplied O2 gas, and then the oxidized precursors form adsorptive sites. On the other hand, the Ti precursors form adsorptive sites by holding their own oxygen on the film surface. Then, under the proposed model, atomic incorporation rates and overall sticking coefficients for BST film depositions were numerically calculated. The calculated results were found to be in good agreement with the experimental results for several molar source ratios with different O2 flow rates of 0.1, 0.5, and 1.0 slm.

A plasma treatment for controlling the relative dielectric constant (e r ) of fine-scale lead zirconate titanate (PZT) rods was developed. This new method made it easy to control e r of 1-3 piezoelectric composites, which were made up of fine-scale PZT rods in epoxy resin. The PZT rods were fabricated using the LIGA process, realizing an array of PZT rods with a cross section, height and volume fraction of 25 μm square, 250 μm and 25%, respectively. The new method consists of a plasma treatment applied before sintering of the PZT rods. By controlling the output RF power and duration of the plasma treatment, e r could be controlled between 250 and 400. Although extended plasma etching reduced e r , there were no changes in the piezoelectric properties and no defects in the sintered body. The ability to control e r of piezoelectric composites allows good electrical impedance matching with the electric circuit of diagnostic systems, thereby reducing signal transmission losses. Changing e r by varying the piezoelectric material or the sintering conditions requires lengthy process optimization. In contrast, controlling e r to establish a good impedance match can be done relatively easily with this new plasma technique because the piezoelectric properties are not affected.

Summary Background: There is compelling evidence for the pivotal role of Helicobacter pylori in the pathogenesis of gastrointestinal ulcer disease. However, despite the bacterium's toxicity, the majority of H. pylori infections are not accompanied by gastric ulcers. This implies the existence of a host mechanism offsetting H. pylori toxicity. Aims: To evaluate gastric fibroblasts' expression of hepatocyte growth factor (HGF), which is known to facilitate gastric ulcer healing, in the presence of H. pylori; to compare the effect on H. pylori-induced HGF expression of a COX-2 selective inhibitor with that of nonselective nonsteroidal anti-inflammatory drugs (NSAIDs). Methods: Human gastric fibroblasts were cultured from human gastric mucosa obtained at surgery. Prostaglandin E2 (PGE2) and HGF were measured by EIA. The expression of COX-2 mRNA was assessed by the TaqMan quantitative RT-PCR system. Results: H. pylori increased PGE2 release in gastric fibroblasts. H. pylori induced expression of COX-2 mRNA, which indicates that PG induction by H. pylori is through COX-2. Sulindac sulphide, etodolac and NS 398 all inhibited H. pylori-induced PGE2 release to the same extent. These agents also inhibited H. pylori-induced HGF release. Conclusion: Gastric fibroblasts produce PG and HGF in response to the presence of H. pylori, which may be considered part of the human body's defensive reaction to H. pylori toxicity. This defensive mechanism is inhibited not only by COX-2 nonselective NSAIDs but also by a COX-2 selective inhibitor. These findings indicate the importance of COX-2 in chronic H. pylori infection.

Neutron spectra produced from a thick lead target bombarded with 0.5 and 1.5 GeV protons have been measured in order to provide experimental data for benchmarking the medium-energy particle transport calculations. The accurate neutron spectra were obtained in the energy region between 1.6 and 150 MeV. The measured data have been compared with the calculated results of an NMTC/JAERI-MCNP-4A code system. The calculation reproduces the experiment fairly well for the lower energy less than 10 MeV. It, however, gives about 50% lower neutron flux in the energy region between 20 and 80 MeV. By using the in-medium nucleon–nucleon scattering cross sections, this disagreement has been reduced.

Double differential (n, xp), (n, xd) cross sections of carbon and aluminum were measured for 65 and 75 MeV neutrons at angles between 12° and 70° using ΔE-E telescopes at a 7Li(p, n) neutron source...

Gamma-ray production double-differential cross sections have been measured for 0.8, 1.5 and 3.0 GeV protons incident on C, Al, Fe, In and Pb targets. Gamma-rays were detected by NEZ13 liquid scintillators and gamma-ray signals were separated from neutron ones by a two-gate integration method. The photomultiplier-charge data of gamma-rays were unfolded with the FERDo-U code. Because of rather thick targets, effects of secondary particles on gamma-ray generation had to be removed and they were evaluated by particle transport calculations with the NMTC/JAERI, MCNP4A and HETC-KFAZ codes. Attenuation of gamma-rays in the target was calculated by the EGS4 code. Gamma-ray production cross sections were obtained in a gamma-ray energy range up to 60MeV. The experimental results were compared with calculated values by the HETC-KFAZ code. At gamma-ray energies up to 10MeV, the calculated cross sections agree with experimental data for the Fe, In, and Pb targets typically within a factor of two.

This paper describes the LIGA process using a 600-MeV superconducting compact synchrotron light source. Deep-etch X-ray lithography is conducted using a new resist and mask. The resist is composed of a copolymer of methyl methacrylate (MMA) and methacrylic acid (MAA). Its main benefit is its high sensitivity, which is one order of magnitude greater than that of polymethyl methacrylate (PMMA) conventionally used in the LIGA process. The mask is composed of a 2-μm-thick silicon nitride membrane with high transparency, supporting a 5-μm-thick tungsten absorber. Experimental results for deep-etch X-ray lithography, electroplating, and molding techniques are presented. A micro-ultrasonic transmitter obtained using these techniques is also described. The purpose of this study is the realization of low-cost microcomponents for a variety of industrial applications. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(1): 40–48, 1997

Neutron-production double-differential cross sections were measured for the spallation reaction induced by 0.8, 1.5 and 3.0GeV protons on C, Al, Fe, In and Pb targets. The experiments were performed by time-of-flight technique with a typical flight path length of 1 m, and the cross sections were obtained with energy resolutions better than 8% at neutron energies below 100MeV. The experimental data were compared with the results of calculation codes based on an intranuclear-cascade-evaporation model. Adoption of the in-medium effect on nucleon-nucleon cross section in the cascade calculation improves the agreement between the calculated results and experimental data particularly in the case of 0.8-GeV proton incidence. For protons above 1GeV, however, the calculations typically twice overestimate the cross sections in the emitted neutron energy region of 10 to 30MeV.

The copolymer of methyl methacrylate and methacrylic acid was developed as a new sensitive resist for the LIGA (Lithographie, Galvanoformung, Abformtechnik) process. The resist exposures were carried out at the LIGA beamline of a superconducting compact light source NIJI-III. The absorbed energy density required to remove the entire exposed resist and produce a defect-free microstructure was between 0.4 and 7 kJ/cm3 (4 and 20 kJ/cm3 for PMMA). The sensitivity and patterning depth of the copolymer were 10 times and 3.5 times, respectively, those of poly methyl methacrylate (PMMA) assuming that both resists were exposed to synchrotron radiation (SR) of the same wavelength. Moreover, the copolymer showed high contrast and process stability.

To elucidate the role of Kupffer cells in ischemia-reperfusion-induced hepatic injury, hepatic injury induced by ischemia-reperfusion was analyzed after modulation of Kupffer cell function. Ischemia of the liver was performed by occlusion of both the portal vein and hepatic artery, which enter into the left lateral and median lobes of the liver. Blood flow in the ischemic lobe was reduced, in contrast to an increased blood flow in the nonischemic lobe during occlusion of the veins. Although hepatocyte damage was not demonstrated by ischemia for

In a previous paper, we demonstrated proteinous chemotactic factors released from hepatocytes exposed to ethanol. In this study, we further characterized the chemotactic factors released from ethanoltreated hepatocytes. After fractionating the conditioned medium with gel chromatography, we demonstrated chemotactic activity at molecular weights of around 20 and 40 kD. When the conditioned medium was mixed with antiserum against interleukin-8, chemotactic activity was almost completely abolished. In addition, antiserum against interleukin-8 completely reduced chemotactic activity of the 20-kD chemotactic factor but did not influence the chemotactic activity of the 40-kD chemotactic factor. After gel electrophoresis of the conditioned medium, the protein reacted with antibody against interleukin-8 was demonstrated at a molecular weight of 20 kD but was not found at a molecular weight of 40 kD. These results suggest that a major part of the proteinous chemotactic factors released from hepatocytes exposed to ethanol could be a dimer form of interleukin-8, one of the proinflammatory cytokines, possibly contributing to the pathogenesis of alcoholic hepatitis. (HEPATOLOGY 1993;18:1477–1482.)

We have been following a male case of congenital sodium diarrhea (CNaD), who had a distended abdomen, passed watery stools with high sodium concentration, and showed metabolic acidosis in the first week of life. He also showed hyponatremia, low urine sodium, high serum aldosterone and high renin activity. Other possible causes of secretory diarrhea were ruled out. The initial effective treatment was oral supplements of water and electrolytes lost in the fecal fluid: with this he gained weight, and hyponatremia and metabolic acidosis were corrected. Loperamide hydrochloride was administered to increase intestinal absorption of sodium, as the serum prostaglandin was high. Watery diarrhea then improved, but as he passed acholic stools, we stopped and postponed the treatment for a while; the stools then became watery again. Although diarrhea has persisted, he has not shown any abnormalities in growth or psychomotor development for the first two years of life.

In an attempt to clarify a mechanism of macrophage infiltration in galactosamine-induced hepatic injury, we investigated chemotactic factor(s) generated by murine hepatocytes exposed to galactosamine. Hepatocytes, isolated from murine liver by perfusion and digestion with collagenase, were incubated with galactosamine. Conditioned medium was collected 24 h later and chemotaxis of murine spleen cells was measured by stimulation of the conditioned medium using a modified Boyden chamber. Chemotactic activity was demonstrated in the conditioned medium of hepatocytes exposed to more than 3 mM galactosamine. Chemotactic activity of the conditioned medium was not reduced after freeze-thawing, and found to be dialyzable (molecular weight12,000). Trypsin (0.25%, 37 degrees C, 30 min) or heat (56 degrees C, 30 min) treatment reduced chemotactic activity of the conditioned medium. Furthermore, chemotaxis of spleen cells was decreased in the presence of lipoxygenase inhibitors (azelastine, ketotifen). These results suggest that accumulation of macrophages in the liver could be mediated by chemotactic factor produced by the galactosamine-treated hepatocytes, and that this mechanism may contribute to the pathogenesis of hepatic injury induced by galactosamine.

Polycyclic Aromatic Hydrocarbons generated in the combustion processes of fuel rich hydrocarbon flames are considered to be important precursors of soot that causes environmental pollution. On the other hand, in a combustion process under low pressure conditions, the generation of fullerenes which are one of large cage-shaped carbon clusters was reported. Combustion synthesis of fullerenes is expected to be one of the mass production methods of fullerenes and a premixed flame of toluene and oxygen is utilized in real mass production process of fullerenes. However, the fullerene formation mechanism from PAH in toluene and oxygen premixed flames has not been clarified yet. Therefore, in the present study, contents of PAH and fullerene in the total soot obtained from premixed flames of toluene and oxygen surrounded with premixed flame of methane and oxygen under various physical conditions were analyzed through gas and liquid chromatography. In the present study over 5 weight percent PAHs were found in the collected soot samples and 22 kinds of substances in PAHs can be specified by using the standard sample and 10 isometric structures of PAHs can be specified by using a gas chromatograph system. When the flame fluctuation was small because of low flow rate of the center and outer flames, the fullerene content in the soot sample increased and the PAH contents of lower molecular weight increased with the increase of the pressure in the chamber. When the flame fluctuation was relatively large because of high flow rate of the center and outer flames, the fullerene content in the soot sample had the maximum peak and the PAH contents of lower molecular weight were dramatically changed from those in the case with small flame fluctuation. Contents of C60 in the total fullerenes increased and those of C70 decreased with the increase of the pressure in the chamber.Copyright © 2007 by ASME

We investigated the reduction mechanism of surface oxide on aluminum alloy powders containing magnesium, by x-ray photoelectron spectroscopy using synchrotron radiation (SR-XPS). The reduction is the initial reaction in a new aluminum nitridation method developed by one of the authors. In heating the powders to 823 K, magnesium soluted in the powders moves from the inner region to the surface at temperatures below 573 K, and finally, above 773 K, the magnesium reduces the aluminum oxide of powder surfaces by chemical reaction, which breaks the surface oxide films, and metallic aluminum appears on the topmost surface of the powders. These results suggest that the SR-XPS system is very useful for dynamic chemical reaction analysis of the surface via in situ measurement.

In an attempt to clarify the mechanisms of neutrophil-accumulation in the liver of alcoholics, release of KC/gro protein (intercrine cytokine family) from hepatocytes in the chronically ethanol fed rats was examined. Chemotactic activity for rat neutrophils was demonstrated in the culture supernatant of hepatocytes isolated from the ethanol fed rats, which was then inhibited in the presence of antibody against rat KC/gro protein. Immunoblot analysis revealed that the peptide reacted with antiserum against KC/gro protein was demonstrated at a molecular weight of 20-23kDa, and an amount of KC/gro protein released from the hepatocytes of the chronically ethanol fed rats was increased, as compared with that of the control rats.

We investigated the exchange-coupling fields of CoFe/Ru (tRu)/CoFe synthetic antiferromagnetic (SyAF) structures with a Ru underlayer and capping layer before and after annealing at 300 and 350 °C. Exchange-coupling field Hex decreased after annealing and distribution increases in Hex were observed in the structure of smaller tRu, especially at tRu≤0.7 nm. Remanence magnetizations increased at smaller tRu. These results indicate that distribution is caused by the existence of the antiferromagnetic coupling of locally various coupling fields due to annealing. A larger exchange-coupling field after high temperature annealing can be obtained by suppressing the distribution of the exchange coupling in the SyAF structure.

A partir de derives de malonates de diallyle ou d'allyle et d'ethyle, synthese d'acides carboxyliques et de monoesters

An array of lead zirconate titanate (PZT) rods whose cross section is 25 µ m square was fabricated using synchrotron radiation (SR) lithography, and the effects of the aspect ratio (height/width) of the PZT rod on 1-3 piezoelectric composite properties were studied. The aspect ratio was between 3 and 9. Mechanical quality factor and acoustic impedance were found to depend weakly on the aspect ratio. However, electromechanical coupling coefficients were found to increase as the aspect ratio increased. Based on the result of deformation simulation by the finite element method (FEM), this dependence was found to be caused by the increase in piezoelectric coefficients as the aspect ratio increased.

The (111) faces of photographic tabular emulsion grains (AgBr microcrystals) have been studied by atomic force microscopy (AFM). The oriented single layers of tabular emulsion grains were formed on indium tin oxide (ITO) bases, and atomic images of the surfaces of microcrystals were observed in air as well as in water. Although the atomic images of (111) surfaces of tabular emulsion grains observed in water coincide with the ideal atomic arrangement of the (111) face of an AgBr crystal, those observed in air do not.

The structure of the Au clusters dispersed on the AgBr microcrystals is investigated by fluorescence EXAFS technique. The results show the definite similarity between the sample and Au metal foil. The formation of small Au metal clusters on the surface of the AgBr microcrystals is suggested.

Response of trapped ions when a clearing voltage was turned off was observed with a charge coupled device (CCD), detecting the time variation of the synchrotron radiation (SR) intensity from the central density of electrons in the stored beam. This enabled us to estimate the neutralization factor and compare it to that obtained from measurements of the betatron tune shift. It is expected that this new method will contribute to the study of ion trapping.

The effects of synchrobetatron resonance on a low-energy beam were studied using a compact storage ring. The beam profile and lifetime were measured on and off the resonance line. Although the first and second resonances were dangerous, the beam lifetime became long on the third and fourth resonances due to the vertical beam size enlargement. Through DC ion clearing, it was also found that the betatron tune shift and spread, which are caused by trapped ions, were reduced with a decrease in beam energy, contrary to expectations. These results indicate that the operating point for injection is not particularly limited in narrow regions. Moreover, the possibility of high current beam storage at low energy is suggested by making full use of the third and fourth resonances.

Stereoregular polymethacrylates containing adenine, uracil, or theophylline residues in the side chains (4a–c), were prepared starting from isotactic and syndiotactic poly[1-(2-bromoethoxycarbonyl)-1-methylethylene] (2) by reaction with the sodium salts of the corresponding nucleic bases. NMR- and UV-spectroscopic studies of the polymers were carried out.

Oxygen-derived free radical generating capacity of polymorphonuclear cells in 27 patients with ulcerative colitis, 10 with acute bacterial diarrhea and 20 healthy volunteers, was measured by the luminol-dependent chemiluminescence method by stimulation of formyl-methionyl-leucyl-phenylalanine. Oxidative free radical generating capacity of polymorphonuclear cells in patients with active ulcerative colitis was markedly enhanced as compared with control (p less than 0.01), while this enhanced free radical production by the cells was not detected at remission stage. Serial analyses revealed that oxidative free radical production by the cells in patients with ulcerative colitis was markedly enhanced with clinical deterioration of the disease, but it returned to normal level with an improvement of clinical features. These results suggest that the increased oxidative free radical production by polymorphonuclear cells could be related to the pathogenesis or aggravation of ulcerative colitis.

In the polymerization of acrylonitrile initiated with α,α′-azobisisobutyronitrile, triphenylphosphite exhibited two different effects on the rate of polymerization, a decreasing effect and an increasing effect. The decrease is due to the phosphoranyl radical formed by the addition of a 2-cyanopropyl radical to triphenylphosphite. The increase is due to the formation of a weak n-π complex between triphenylphosphite and acrylonitrile, which was confirmed from the UV absorption spectra. Triphenylphosphite had no significant effect on the molecular weight of the polymer. The phosphorus content in the polymer was small (0.02–0.06%), the number of phosphorus units in one polymer chain being 1–4. Bei der radikalischen, durch Azoisobuttersauredinitril initiierten Polymerisation von Acrylnitril (AN) bewirkt zugesetztes Triphenylphosphit (TPP) je nach der angewendeten Menge entweder eine Verlangsamung oder eine Beschleunigung der Reaktion. Es wird angenommen, das die Verlangsammung auf der Bildung relativ reaktionstrager Phosphoranylradikale aus TPP und 2-Cyanoisopropylradikalen beruht. Die Beschleunigung der Reaktion bei groperem Zusatz von TPP wird mit der Bildung eines lockeren Komplexes aus AN und TPP erklart, der durch UV-Spektren nachgewiesen wurde und der schneller polymerisiert als das reine AN. TPP hat keinen signifikanten Einflus auf die Molekulargewichte der Polymeren. Der sehr geringe Phosphorgehalt (0,02–0,06%) entspricht einer Menge von nur 1–4 Atomen P pro Makromolekul.

A partir de derives de malonates de diallyle ou d'allyle et d'ethyle, synthese d'acides carboxyliques et de monoesters

Tyrosine hydroxylase (TH) activity has been determined in 22 neuroblastoma tumors from 15 patients, in 1 pheochromocytoma, 20 adrenal glands, 10 other tumors and organs, and 4 specimens of sera. The enzyme activity was found only in the neural crest tumors and adrenal glands, but the levels were too low to be detected in the other tumors and in normal liver and kidney tissues. The average specific activity (mean +/- SE) of TH in 23 neural crest tumors was 0.559 +/- 0.101; in 20 adrenal glands was 0.418 +/- 0.124 nmol/mg protein/minute. In 13 patients with neuroblastoma and 1 patient with pheochromocytoma, both TH levels in the primary tumors and urinary excretion of vanillylmandelic acid (VMA) and homovanillic acid (HVA) were studied. The urinary excretion of VMA by 10 of 13 neuroblastoma patients and by the patient with pheochromocytoma was significantly to markedly elevated above normal levels; excretion of HVA by 12 of 13 neuroblastoma patients was similarly elevated. These results indicate that tyrosine hydroxylase, an enzyme specifically located in the adrenal medulla and monoaminergic neurons, is also present in neuroblastoma, a malignant tumor of similar embryologic origin, and in pheochromocytoma. Not only can TH activity in these tumors be demonstrated in vitro, but the elevated urinary excretion of VMA and/or HVA by the majority of patients with these tumors also indicates TH activity of the tumors in vivo.

The design parameters of a compact synchrotron radiation (SR)ring dedicated to industrial X-ray lithography are discussed. Further studies have been continued for making the SR ring and its injector smaller to complete a practical SR system. The Electrotechnical Laboratory and Sumitomo Electric Industries, Ltd. jointly completed a conventional compact test ring "NIJI-1 (rainbow-1 in English)" and succeeded in SR generation on February 1986. Presented here are useful results indispensable for the development of a compact SR system.