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Organic anions can uncouple bile salt secretion from the secretion of phospholipid and cholesterol. The uncoupling mechanism appears to be dependent on the type of anion present. To investigate the effect that different uncoupling mechanisms may have on the flow of bile and its composition, rats were depleted of bile salt pool by overnight biliary diversion and reinfused intravenously with sodium taurocholate (STC) at a constant rate (160 nmol/min per 100 g b.w.). After bile salt secretion had achieved a steady state, sulfobromophthalein (BSP) or papaverine was continuously administered at a rate of 100 nmol/min per 100 g b.w. with STC. During the intravenous infusion of BSP or papaverine, the output of biliary lecithin and cholesterol decreased without affecting bile salt output. The degree of fatty acyl chain saturation in biliary lecithin was increased by BSP infusion and decreased by papaverine infusion. The mechanism by which bile salt secretion is uncoupled from the secretion of phospholipid and cholesterol affects the acyl chain composition of secreted lecithin. The changes in composition of lecithin acyl chains may reflect the intervention by different anions at different points in the lipid transport pathway.

We have observed space charge profiles using the PEA (pulsed electro-acoustic) system in low density polyethylene (LDPE) and cross-linked polyethylene (XLPE) under high electric dc field to study a relationship between space charge behavior and dielectric breakdown. XLPE, which is used as an insulating material of ac power cable, is also expected to be applied as the insulating layer of DC long distance power cable. To apply the polymeric materials for the insulating layer of a dc power cable, it is necessary to understand the "space charge" effect under high dc stress. In our previous research works, we have found that a large amount of, so called, packet-like charge generates in LDPE under dc high electric field of more than 100 kV/mm and it enhances the electric field locally in balk of the sample, and finally it leads a breakdown. On the other hand, such breakdown process has not been reported for XLPE yet. Because it was difficult to get a thinner XLPE sample as LDPE was. However, since we need to understand the relationship between the space charge and the breakdown in XLPE, we tried to measure them using specially arranged PEA system for high voltage application. In this report, we investigate the space charge formation and electric breakdown characteristics in XLPE. As the results, it is found that the relationship between the space charge and the breakdown in XLPE is completely different from that in LDPE. Since the XLPE was chemically made from LDPE using cross-linked agent at high temperature. It is assumed that the breakdown strength in XLPE is strongly affected by both of the residues of the cross-linking by products and the heat history.

The space charge accumulation processes in polyimide film under corona discharge from spherical electrode are observed using improved open-electrode type PEA (pulsed electro-acoustic) measurement system. To reduce the electric power consumption, the efficient-energy motor is required to be developed. One of effective improvement of the efficiency of motors is to increase the driving voltage for it. However, if the driving voltage is increased, a large, so called “inverter serge voltage” is applied to the coating insulating material for the motor windings, then partial discharge (PD) occurs between the wires or the wire and the grounded metal of the motor. The partial discharge gives serious damages to the insulating material and it leads the breakdown finally in the insulating material. Therefore, it is important to understand the mechanism of the generation of partial discharge. Especially, the space charge formed in the insulating material under such condition is supposed to affect the generation of the partial discharge. However the relationship between the space charge and the PD haven't been cleared yet. Therefore, we have tried to measure the space charge accumulation in the material under corona discharge using PEA system. In this report, some typical results of space charge profiles measured after surface discharge are introduced. As the results, we have found that the space charge formation in polyimide film under corona discharge is easy to accumulate.

A large quantity of hetero charge was observed in polyimide (Kapton®-H) film subjected to high electrical stress of 100kV/mm and under the condition of high humidity. In order to investigate the hetero charge accumulation, Quantum Chemical Calculation was applied to a small piece of polyimide specimen for obtaining an energy band structure, a band gap and an electric carrier trap level. Furthermore, it is discussed that a dipole moment of a series of water molecules made a narrow band gap in the polyimide chain, which increased more hetero charge, and finally led to a thermal breakdown by increasing conductivity.

Space charge accumulation and conduction current in low density polyethylene (LDPE) incuding cumylalcohol under dc high electric field were investigated using improve PEA (pulsed electro-acoustic) measurement system. In the bulk of XLPE that is being used for power transmission cables, there remain some chemical residues of crosslinking by-products such as α-methylstyrene, acetophenone and cumylalcohol. Such residues are assumed to affect the space charge formation and the increase of the conduction current followed by the breakdown. Especially, cumylalcohol seems to remain in XLPE for long time even in thin test film because it is non-volatile at room temperature. Therefore, several kinds of research about the effect of cumylalcohol on the space charge behaviors in LDPE have been carried out. To elucidate the breakdown mechanism in the sample, we measured the space charge density distribution and the external current simultaneously using the improved PEA measurement system. Moreover, we discussed the process of the breakdown based on the conduction current and dissipation energy distributions which are calculated from the measurement results.

If a power semiconductor module becomes compact to enhance its wiring density, the electric field at its insulation part should become high. This in turn causes the increase in heat generation per unit volume. Therefore, epoxy resin with high thermal conductivity, a low thermal expansion rate and good anti-aging performance is required. In this regard, we made nano-micro composites (NMCs), namely epoxy resin samples containing both nano-silica filler having high insulating performance and micro-alumina filler having a high thermal conductivity, and observed electroluminescence (EL) and dissipation current waveforms under AC high electric fields for these NMCs simultaneously in order to examine the effects of addition of fillers with different sizes. As a result, it was found tCharge behaviorhat both dissipation current and the number of EL pulses depend on the sample thickness. It was also found that the addition of alumina-micro filler alone into epoxy resin increases the number of EL pulses compared to the neat epoxy and that the NMC shows improved insulating properties. It was also confirmed that the relative permittivity is around 4 for the neat resin and the NMCs, independent of the thickness and the type of fillers.

Effect of electron beam irradiation on dielectric properties in various insulating materials for spacecraft is investigated using PEA (Pulsed Electro-Acoustic) method. In space environment, spacecraft is exposed to plasma or radioactive-rays. In such condition, multilayer insulating materials covering the spacecraft are charged up. Sometimes the charge accumulation causes to the serious damage to the electric devices and degradation of insulating materials. To investigate the change of the electrical properties of dielectrics by electron beam irradiation, we measure the space charge distributions and the conduction current in some e-beam irradiated materials under dc stress. From the measurement results, it was found that the large amount of charges accumulated in some irradiated materials under dc stress, while almost no charges accumulated in the non-irradiated materials under the same stress.

Space charge distributions in multilayered polyimide films under dc high stress was measured using pulsed electro acoustic (PEA) method. Judging from our previous research works, the space charge accumulated in a single layer polyimide film under dc high electric field is closely related to electrical breakdown. However, there is almost no example to investigate the space charge accumulation characteristics in the multilayered polyimide films. Since the multi-layered films are usually used for a printed circuit board of electronic devices or a cover layer of motor windings, it is necessary to investigate the space charge accumulation properties in the multi-layered films to improve the insulating system for them. In this paper, we measured the space charge behavior in multilayered polyimide films using the PEA method under dc high electric field at 80°C. Furthermore, we measured the conductivity in the multilayered polyimide films to analyze the space charge degradation process. From the space charge distribution measurements, we found that the insulation performances of the multilayered samples are better than that of the single layer sample. From the conductivity measurements, we found that the conductivity increased after the voltage application which generated the space charge accumulation.

In rectal cancer, lateral lymphatic spread is considered to worsen the prognosis. Therefore, accurate determination of lymph node involvement preoperatively is helpful in assessing the malignant character of the tumor and in determining resectability. The present study was performed to evaluate the accuracy, limitations, and usefulness of endoluminal ultrasonography in preoperatively diagnosing the localization of lymph node metastasis in rectal cancer. Seventy-six patients with rectal cancer underwent preoperative endoscopic ultrasonography. Three of these patients had lateral lymphatic spread and all could be distinguished on endoscopic ultrasonography by the detection of involvement of lymph nodes in the anterior rectal space. These findings suggest that endoscopic ultrasonography plays a potentially useful role in the strategy for dealing with rectal cancer prior to surgery.

In this study, we develop a system for measuring the volume resistivity of a polyimide film in a simulated space environment and investigate the effect of sample temperature and incident electron beam energy on the volume resistivity of the film. The temperatures in the experiment range from 233 K to 353 K and are controlled by a temperature control system that uses Peltier devices. The incident electron energy is varied from 10 keV to 40 keV. The experimental results indicate that volume resistivity of the polyimide film decreases as its temperature increases in line with the Boltzmann model. The higher energy electrons penetrate deep into the experimental sample of spacecraft surface material and enhance conductivity, which results in a decrease in volume resistivity owing to radiation-induced conductivity (RIC).

Spacecraft have a serious damage due to the electrostatic discharge accident. Although the polymeric materials are used for surface materials of spacecraft as a multi layer insulator (MLI) and optical solar reflector (OSR), those materials are charged up due to radioactive rays, especially electrons and protons. The charge accumulation is the origin of aging and discharging phenomena, furthermore those become a trigger for spacecraft operation anomaly. Therefore, we need to obtain the dielectric property of those materials. As the dielectric property, for example conductivity, have a great relationship between charge accumulation in the bulks, we especially focused polyimide films (PI) for MLI and fluorinated ethylene propylene copolymer (FEP) for OSR irradiated by high energy proton. We measured the space charge distribution in the bulks during and after proton beam irradiation by the pulsed electroacoustic (PEA) method. From the results, it is found that positive charge accumulations are observed in the bulk at the position of proton penetration depth. Furthermore, we measured the current through the bulk and space charge behavior in irradiated and non-irradiated PI under HV-DC by ASTM and PEA methods. From the above results, we discuss and estimate the aging of electrical insulating characteristics on the polyimide films and the fluorinated ethylene propylene copolymer films irradiated by proton.

The space charge accumulation properties under dc high stress at various temperatures were investigated in cross-linked polyethylene (XLPE) and XLPE/Carbon composite. We have reported, earlier, that low density polyethylene (LDPE) including inorganic nano-size filler shows a good performance without accumulation of space charge even under very high dc electric field. Since it can be thought that the nano-size filler with the higher permittivity shows the superior effect of suppression of the charge injection from electrodes into the bulk of sample under dc high stress, we tried to use the conductive nano-size filler which has the infinite permittivity ideally. In this report, we have tried to investigate the space charge accumulation properties of XLPE with and without graphene nano-filler.

We studied how to measure the secondary electron emission (SEE) of metal and insulating materials used for satellite thermal insulation or other such purposes. SEE yield measurement is very important for analyzing charge accumulation on the satellite surfaces due to the space environment because electron emission for irradiated electrons influences the amount of surface charge. Therefore, we are developing the measurement system without the deceleration voltage and enable to obtain the characteristics of the SEE yield from insulation materials irradiated by an electron beam with energy of 300 eV to 5 keV. This report introduces the developed measurement system and the SEE yield measurement results of metal sample and Polymer (polyimide and FEP). From those results, we discuss the characteristics of SEE that depend on each material. Furthermore, we also propose a future plan of SEE measurement for satellite materials.

Recently, the switching frequency of motors for automotive and railway cars are increased according with the innovation of power semiconductor technology. When the switching speed is increased, so called “inverter surge voltage” is increased, then the coating insulating materials are degraded due to the high voltage phenomena like partial discharge, dielectric heating and space charge accumulation. Since the degradation of the insulating materials can lead to failure of motors, it is necessary to investigate the degradation for safety motor drive. While many researches of partial discharge affected on the insulating degradation of the coating materials for windings have been reported, the investigations of the degradation by the space charge accumulation have not been reported yet. Therefore, in this report, we have investigated the space charge behavior in polyamide-imide(PAI) and polyester-imide(PEI), which are usually used as the coating insulating materials for motor windings, under DC high voltage using PEA(Pulsed Electro-Acoustic method) method. It is found that the space charge formation depends on the polarity of applied voltage, and it is also found that the moisture in the sample promotes the space charge accumulation.

Dynamic two-dimensional discharge patterns on various polymeric materials under atmospheric and low pressures are carried out using a newly developed measurement system based on Pockels effect. Spacecraft in space environment are exposed to high energy particles and radio-active rays. When the high energy particles impinge onto the surfaces of spacecraft polymeric materials they are charged, bringing sometimes to surface discharges that often can cause serious accidents. Since many accidents due to such irradiation effects are reportedther is a need to investigate deeper the discharging effects on the surface of polymeric materials under low pressure.

We evaluate the dielectric characteristic of polymeric materials for MLI (Multi Layer Insulator, a kind of thermal insulation material) for spacecraft under high energy proton irradiation using results of space charge distribution. Spacecrafts have a serious damage due to the electro-static discharge accident. The electric charges are accumulated in the polymeric materials due to radioactive rays, especially electrons and protons. The charge accumulation is the origin of aging and discharging phenomena, furthermore those become trigger for spacecraft operation anomaly. Therefore, we need to obtain the space charge distribution in the bulks. In this study, we especially focused polyimide films for MLI irradiated by high energy proton. We measured the space charge distribution in the bulks during and after proton beam irradiation. From the results, it is found that positive charges accumulate in the bulk at the position of proton penetration depth. We also obtained same tendency from the results of conductivity measurement treated by ASTM method. From the above reason, we have studied the dielectric characteristics of MLI materials irradiated by radioactive rays, especially we focused the condition of proton irradiation. In this paper, we discuss the dielectric phenomena and the relationship between conductivity and charge accumulation in bulks.

It is found in our previous work that hetero space charges always observed before breakdown occurs in polyimide film under high DC electric field. We have also found that the time-to-breakdown and the accumulated amount of hetero space charges depend on the applied DC electric field. In this report, we have investigated whether the time-to-breakdown and the space charge accumulation depend on the applied voltage wave form or not. By measuring the space charge accumulation using PEA method, it is found that the very close space charge behavior in polyimide film is observed under rectangular voltage application to that observed under DC voltage application. Under high DC electric field, homo charges accumulate at first and they decrease. Following the decrease of homo space charges, the hetero charges appear near electrodes and finally the breakdown occurs. Such process to breakdown was also observed under the application of rectangular voltage wave form. Net voltage application time in rectangular voltage is sometimes close to the time-to-breakdown under DC electric field. However, the time-to-breakdown seems to strongly depend on the humidity of the experimental condition.

Space charge distribution and external current in low density polyethylene (LDPE) have been measured simultaneously using an improved PEA (pulsed electro-acoustic) measurement system. They are usually measured using different devices independently. However, to investigate the relationship between the space charge behavior and the conduction current, it is necessary to measure them simultaneously in the same sample. Therefore, we have developed an improved PEA system to measure them simultaneously. In this improved system, the space charge distribution and the external current measurements are carried out by switching connection of the lower electrode between electrometer and ground. As the result of simultaneous measurements, it is found that the external current increases during the injection and traveling of positive charge from the anode towards the cathode. To explain the phenomenon, we estimated displacement current, conduction current and conductivity distributions in the sample from the results of the measurements. Moreover, we examined the relationship between those distributions and charge behavior in LDPE.

We evaluate the dielectric characteristic of polymeric materials for MLI (Multi Layer Insulator, a kind of thermal insulation material) for spacecraft under high energy proton irradiation using results of space charge distribution. Spacecrafts have a serious damage due to the electro-static discharge accident. The electric charges are accumulated in the polymeric materials due to radioactive rays, especially electrons and protons. The charge accumulation is the origin of aging and discharging phenomena, furthermore those become trigger for spacecraft operation anomaly. Therefore, we need to obtain the space charge distribution in the bulks. In this study, we especially focused polyimide films for MLI irradiated by high energy proton. We measured the space charge distribution in the bulks during and after proton beam irradiation. From the results, it is found that positive charges accumulate in the bulk at the position of proton penetration depth. Furthermore, the characteristics of space charge accumulation are difference between the current and energy of irradiated proton. In case of comparison between high and low dose rate irradiation under same total dose condition of both irradiation, the mobility of accumulated charges increase with rate increment. We also obtained same tendency from the results of conductivity measurement treated by ASTM method. From the above our descriptions, we discuss and estimate the aging of dielectric properties on the polyimide films irradiated by proton in this paper.

We studied the measurement of photoelectron emission (PE) of metal and insulating materials used for thermal insulation on satellites or other such purposes. The PE measurement is very important for analyzing charge accumulation on satellite surfaces in a space environment because photoelectron emission is related to the amount of surface charge. Based on these photoemission characteristics, we deduce that the risk of electrostatic discharge for a satellite in the day position is lower than that in the night position.

Relationship between breakdown strength and space charge formation in polyimide film under dc high stress at various temperatures is investigated using pulsed electro-acoustic (PEA) method. Polyimide films are used for various electric and electronic devices as insulating materials. They are demanded to show a good performance at various condition like at high temperature, under high electric stress with high humidity. Furthermore, since the material is expected to be much thinner, the breakdown characteristic is one of important factors to estimate the material. On the other hand, the space charge formation sometimes strongly affects to dc breakdown strength. Therefore, we have been investigating the relationship between the breakdown and space charge formation in polyimide film. It is found that hetero space charges are always found before breakdown. Since it is always observed before breakdown at high temperature, it may be predictive information for breakdown.

We studied measurement of secondary electron emission (SEE) of metal and insulating materials used for satellite thermal insulation or other such purposes. The SEE yield measurement is very important for analyzing charge accumulation on satellite surfaces for a space environment because electron emission related to irradiated electrons influences the amount of surface charge. Therefore, we tried to measure the SEE yield. Furthermore, we must consider degradation phenomena of surface materials for spacecraft caused by radioactive rays. According to the degradation of materials, those SEE yields might change compared to a non‐degradation sample. Therefore, we tried to measure the SEE yields of surface materials for spacecraft which are treated using the degradation process. For preparing a degradation sample, those samples were irradiated by an electron beam and UV to simulate degradation in a space environment. We take three irradiation conditions for electron beam and UV irradiation that related with GEO ...

This paper describes the study framework for material property measurements related to spacecraft charging, methods, and measurement results. This work specifically addresses analyses and measurements of surface resistivity, volume resistivity, and the dielectric constant. We also explain measurements of secondary electron and photoelectron emissions in this framework.This review is based on joint experimental studies conducted for the Japan Aerospace Exploration Agency (JAXA) at the High Energy Accelerator Research Organization (KEK), at the Musashi Institute of Technology and at the Saitama University to investigate the relation to spacecraft charging. This report introduces a summary of some typical measurement results following a brief explanation of the measurement project.

Satellites have come to play many roles depending on their purpose, including communication, weather observation, astronomy observation, and space development. A satellite requires long life and high reliability in such a situation. However, at an altitude of several hundred kilometers, atomic oxygen (AO) is a destructive factor. With density of about 1015 atoms/m3, AO also has high reactivity. As the satellite collides with AO, surface materials of the satellite are degraded, engendering surface roughness and oxidation. Accordingly, it is necessary to monitor the surface conditions.In this study, photoemission characteristics of several materials, such as metals, glasses, and polymers are measured using a deuterium lamp and band pass filters. The threshold energy for photoemission and the quantum efficiency were evaluated from those measurements. Consequently, for the investigated materials the threshold energies for photoelectron emission were found to be 4.9–5.7 eV. The quantum efficiency of metals is ...

The purpose of our research work is to measure the space charge distribution in proton beam irradiated dielectric materials used for spacecraft. Spacecrafts sometimes have a serious damage due to the electro-static discharge accident. It is said that the charge accumulation in dielectric materials irradiated by high energy particles in space environment causes the discharge accident. Therefore, we need to measure the charge distribution in the bulk of dielectric materials. We have been developing a system for measuring internal charge distribution in dielectric materials using pulsed electro-acoustic (PEA) method. Using the system, we tried to measure the charge distribution after proton beam irradiated polyimide (PI) and Tetrafluoroethylene hexafluoropropylene copolymer, Fluorinated ethylene propylene copolymer (FEP) films which have been used as a thermal control layers or an optical solar reflector of the spacecraft. From the result, it is found that positive charges accumulate in bulk of PI and FEP films after irradiation of the proton beams. However, the amounts of accumulated positive charge in PI increase with increase of irradiation time, while those in FEP not increase. Therefore, it is found that the charge accumulation properties strongly depend on the kinds of irradiation materials.

We studied measurement of secondary electron emission (SEE) of metal and insulating materials used for satellite thermal insulation or other such purposes. The SEE yield measurement is very important for analyzing charge accumulation on satellite surfaces for a space environment because electron emission related to irradiated electrons influences the amount of surface charge. Therefore, we tried to measure the SEE yield. Furthermore, we must consider degradation phenomena of surface materials for spacecraft caused by radioactive rays. According to the degradation of materials, those SEE yields might change compared to a non-degradation sample. Therefore, we tried to measure the SEE yields of surface materials for spacecraft which are treated using the degradation process. For preparing a degradation sample, those samples were irradiated by an electron beam and UV to simulate degradation in a space environment. We take three irradiation conditions for electron beam and UV irradiation that related with GEO and operating period. This report introduce a few results of the SEE yield of the satellite materials applied degradation process simulated space environment and discuss the relationship between the SEE yields and sample degradation when irradiated by an e-beam and UV. Furthermore, we also introduce the new SEE measurement system which can irradiated electron with an energy under 0.6 keV.

Charge accumulation characteristics in dielectric materials for a spacecraft were studied to elucidate spacecraft charging problems in a high-energy radiation environment. This study especially addressed spacecraft charging accidents caused by internal charge accumulation in dielectric materials irradiated by electron and proton beams. Internal charge measurements of those bulk materials were carried out using Pulsed Electro-Acoustic (PEA) and Pressure Wave Propagation (PWP) methods. For internal charge accumulation in the bulk irradiated by a proton beam, results showed a positive charge accumulation in the bulk samples after irradiation. However, a positive charge accumulation was not observed for quartz glass with an Al evaporated layer on the surface of the proton beam irradiation side. Therefore, in this paper, we compare the PEA's internal charge measurement results and energy band model for discussion of the charge formation mechanism in the bulk irradiated by a proton beam. Furthermore, we measure the space charge distribution in bulk materials (e.g., polyimide film, FEP, and cover glass) which are used for spacecraft irradiated by a proton beam during a satellite's orbit. We also measured the space charge distribution in identical samples under electron beam irradiation. The electron beam irradiation conditions resembled those encountered in a GEO synchronous earth orbit (GEO). We compare and discuss internal charge measurement results and charge accumulation results in the same bulk with mono energy electron beam irradiation.

This paper reports on the result of space charge evolution in cross-linked polyethylene (XLPE) planar samples approximately 220 µm thick. The space charge measurement technique used in this study is the pulsed electroacoustic method. There are two phases to this experiment. In the first phase, the samples were subjected to dc 30 kVdc mm −1 and ac (sinusoidal) electric stress levels of 30 kVpk mm −1 at frequencies of 1, 10 and 50 Hz ac. In addition, ac space charge under 30 kVrms mm −1 and 60 kVpk mm −1 electric stress at 50 Hz was also investigated. The volts-off results showed that the amount of charge trapped in XLPE sample under dc electric stress is significantly bigger than samples under ac stress even when the applied ac stresses are substantially higher. The second phase of the experiment involves studying the dc space charge evolution in samples that were tested under ac stress during the first phase of the experiment. Ac ageing causes positive charge to become more dominant over negative charge. It was also discovered that ac ageing creates deeper traps, particularly for negative charge. This paper also gives a brief overview of the data processing methods used to analyse space charge under ac electric stress. (Some figures in this article are in colour only in the electronic version)

We report for the first time the simultaneous measurement of electroluminescence and space charge (SC) distribution in low density polyethylene films under a high dc field, using a specially developed pulsed electro-acoustic apparatus. An interpretation of the observed behaviour is proposed with the help of a numerical model of transport including the effect of charge trapping and recombination. It is shown that the two complementary approaches give consistent information about SC dynamics and charge recombination. This new kind of set-up should open the way for studying hot carrier transport in insulating materials.

This paper reports on space charge dynamics in XLPE samples, which have been pre-stressed under ac electric stress, when subjected to 30 kV/sub dc//mm dc electric stress for 24 hours. The samples used for this study were planar XLPE samples of /spl sim/220 /spl mu/m thick aged under 30 kV/sub pk//mm, 30 kV/sub rms//mm and 60 kV/sub pk//mm at 50 Hz ac condition for 24 hours. In addition, the experiments were also extended to samples that were pre-aged under 1 Hz and 10 Hz ac 30 kV/sub pk//mm for 24 hours.

Bulk charge accumulation in dielectric materials under electron beam irradiation was observed using acoustic measurement techniques. Recently, some accidents in spacecraft due to the charging up of electric potential have been reported. Some of them are caused by surface discharge normally happens in plasma environment. Some others seem to be caused by discharge due to an accumulation of charge in bulk of materials in relatively higher altitude environment. Surface charge is usually measured using surface potential meter. However, there had been no useful method to measure the bulk charge in the materials. Therefore, we have been developing the bulk charge measurement system. The developed system is applicable to measure the charge distribution in dielectrics in vacuum environment under electron beam irradiation. Using the systems, we carried out the measurements of bulk charge distributions in Kapton/spl reg/ film and glass materials under electron beam irradiation. In this paper, summary of some typical measurement results is introduced following the brief explanation of measurement principles.

A novel fat absorption test to clarify the malabsorption syndrome was developed using a micronephelometric technique and compared with the classic conventional technique using 131 I-triolein. An integrity of time-sequential light scattered from chylomicron-related turbidity in serum was determined between 0 and 300 min after butter fat load, being expressed in terms of the light scattering intensity (LSI). A good correlation was obtained between LSI and the serum level of chylomicron-triglyceride determined by an ultracentrifugation technique (r= 0.819, P< 0.001). The maximal LSI was consistently observed at 180 min after administration of a test meal in the normal group (n = 39), whereas the malabsorption syndrome group (n=35) was distinctly different and could be further classified according to four patterns of LSI changes. In addition, an inverse correlation was found between this fat absorption test and the l31 I-triolein absorption test. It was concluded that the micronephelometric technique which does not use a radionuclide is advantageous in its simple and safe evaluation of fat malabsorption syndrome.

We studied how to measure the secondary electron emission (SEE) of metal and insulating materials used for satellite thermal insulation or other such purposes. SEE yield measurement is very important for analyzing charge accumulation on the satellite surfaces due to the space environment because electron emission due to irradiated electrons influences the amount of surface charge. Therefore, we tried to measure the SEE yield. To measure SEE, we used an improved SEM system for SEE measurement that has a beam blanking unit and a Faraday cup. From this system, we can obtain the characteristics of the SEE yield from insulation materials irradiated by an electron beam with an energy of 600eV to 5keV. In this report, we introduce the SEE yield measurement results of reference materials (Au, Ag and Quartz glass) and insulating materials. From those results, we discuss the characteristics of SEE that depend on each material. Furthermore, we also propose a future plan of SEE measurement for satellite materials.

原発性肺癌50例と転移性肺癌5例の腫瘍細胞のケラチン (KR) に対する反応とランゲルハンス系細胞の出現をみるため, 免疫ペルオキシダーゼ法を施行した.細気管支肺胞癌 (BAC) の腫瘍細胞はしばしば抗KR抗体に陽性となり, 多数のS-100 (+) 樹状細胞 (DC) が14例中13例 (92*9%) に出現した.また, S-100 (+) DCは癌組織型に関わらず, 腫瘍周囲のリンパ球浸潤部に出現し, 腫瘍免疫機序に関与している可能性が示唆された.

A molybdenum(IV) aqua ion with sulfur bridges, Mo3OS34+, has been prepared and characterized. An X-ray structure analysis of the iminodiacetato complex prepared from the aqua ion has revealed the core structure of Mo3(μ-O)(μ-S)2(μ3-S).

Electron microscopy and both light and electron microscopic immunohistochemical tests for elastin were employed to study the morphogenesis of the unique elastinophilic fibers of an elastofibroma removed from the subscapular region of a 62-year-old woman. Ultrastructurally, as shown by tannic acid stain, elastinophilic fibers of the elastofibroma consisted of central cores and outer zones. The latter were composed of various sizes of vaguely demarcated, irregularly shaped amorphous components and compactly and randomly arranged large amounts of microfibrils. The electron microscopic immunohistochemical results showed that the small-sized amorphous components and microfibrils in the outer zones of the elastinophilic fibers were stained evenly and of granular texture, but the vaguely outlined large amorphous components were not stained. These findings were interpreted as indicating that the amorphous components of the outer zones of elastinophilic fibers were less compact and allowed the penetration of antielastin antibody. The unique elastinophilic fibers of elastofibromas appear not to be formed by the degeneration of the fibers but by abnormal elastogenesis, including an abnormal arrangement of microfibrils.