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Lateral profiles of electric field and ion current density at ground level were measured precisely in a unipolar/bipolar line to plane geometry under different wind conditions and different dc voltages. Furthermore, the relationship between the field and current density is discussed. In the case of unipolar line in still air, the normalized profiles are approximately independent of the magnitude of the applied voltage and the linear dimensions of the gap, but they are strongly influenced in the bipolar case. The wind effect on the current profile is greatest at voltages close to corona onset for each experimental arrangemeht. The experimental results suggest that the usual wind extends the region of the ionic current flowing . e. the right-of- ay required for HVDC transmis-sion lines) by a factor of two or more as compared with that with no wind.

The existence of four types of cells in the glomerular outgrowths from both normal and nephritic rabbits was confirmed, and their characteristics by phase contrast, scanning electron, and transmission electron microscopy are described. Type I (arborized), Type II (fusiform), Type III (round), and Type IV (paving stone-like) cells presumably originate from visceral epithelial cells, mesangial cells, monocytes, and parietal epithelial cells of Bowman's capsule, respectively, though conclusive evidence is still lacking. The Type III cells, unlike the other types of cells, have a remarkable phagocytic capacity as well as Fc and C3 receptors.

Recent advances in superconducting wire technology, together with economic advantage of superconducting magnets to produce high magnetic field, have stimulated increasing interest in large scale superconducting apparatus such as superconducting magnet energy storage in electric power systems, superconducting magnets for fusion reactors and superconducting power generators. Electrical insulations may become one of critical design factors because high voltages are produced by stringent energy discharge and quenching in large superconducting magnets. In this review, abnormal overvoltage, performance of coolant liquids under high electric field and dielectric performance of insulating components in superconducting apparatus are described.

The relationship among the waveform of corona current, the dripping manner of water drops from a conductor with high d.c. voltage, the corona discharge mechanism, the specific charge (the ratio of charge to mass of the drop) and the radius of water drops is investigated for a wide range of the drop conductivity, whilst the corona discharge mechanism on the drop is discussed. In addition to the corona and the specific charge modes described in a previous paper [1], Pulse-Less Corona (PLC) and the atomization of water is newly determined for highly resistive water. Moreover it is confirmed that with distilled water the maximum specific charge could reach 5 × 10 −3 C/kg and the duration of the current flowing is closely related to the mechanical parameters determining the deformation process of water drops.

Influence de la teneur en ion, de la taille de l'ion antagoniste, de la masse moleculaire. Cinetique de separation de phase de melange avec le polyoxyde de propene

One of the most effective precipitation methods for submicrometer particles is the charged droplet scrubber. The dust collection in the charged droplet scrubber is considered to consist of some processes with respect to the interaction between charged dust particles and a charged water droplet. That is, the charged dust particles are attracted to, collide with, adhere to, penetrate into, rebound from, accumulate on, and reentrain from a charged water droplet. The direct observation of the collection process for dust particles by a charged water droplet was conducted by using the experimental setup designed by the authors. It was found from the experiments that particles with good wettability were captured inside the water droplet, particles with poor wettability floated at regular intervals on the droplet surface, and particles with medium wettability were trapped on or inside the water droplet. When particles were trapped on the droplet surface the growth of dendritic depositions was found, and their behavior was very distinct from those obtained on the fibrous filter due to the fluidity of the droplet surface. The deposition mechanisms of charged particles on the charged water droplet are discussed qualitatively.

Some anomalies in light scattering from polyelectrolyte in semi-dilute solution have been investigated and compared with those observed in high-molecular-weight neutral polymer solutions. Three anomalous in behavior were found: (a) the c/Rθ vs. sin2(θ/2) curve was convex upward at a lower angle θ, (b) the c/Rθ vs. c curve was convex upward, and (c) the Z45 vs. c curve exhibited a minimum. Rθ is the reduced scattering intensity at the scattering angle θ, c the polymer concentration, and Z45 the dissymmetry ratio. Further, it has been pointed out that the plot of logarithm of correlation length ξ against logarithm of concentration c changes its slope at a polymer concentration at which Rθ vs. c curve shows a maximum, i.e., at the critical polymer concentration. In the polymer concentration range above the critical point, lumps of molecules are more certain to exist rather than microgels which are conventionally regarded as the origin of the anomalies.

The immunofluorescent localization of glomerular basement membrane (GBM) antigens was examined in 52 specimens from normal kidneys and in various renal diseases using antisera to human GBM (HGBM), IV type collagen (IV Col) and P3 antigen, a rat nephritogen. Anti-HGBM serum normally stained the GBM and the mesangium in a restrictive pattern, anti-IV Col serum stained the GBM and the mesangium in a wider pattern and anti-P3 serum stained only the GBM. In mesangial proliferative glomerulonephritis, including IgA nephropathy and Henoch-Schönlein nephritis, the widened mesangial areas were stained with anti-HGBM and anti-IV Col sera. In membranous nephropathy, the punched-out lesions of thickened GBM were demonstrated with the three antisera in moderate cases and a double linear distribution with fine granulation with anti-HGBM and anti-IV Col sera were revealed in one severe case. In membranoproliferative glomerulonephritis, the expanded mesangium and thickened capillary walls were stained with anti-HGBM and anti-IV Col sera, while the outer line of glomerular capillary walls was only positive with anti-P3 serum. In crescentic glomerulonephritis, the collapsed glomerular tufts were stained normally with anti-HGBM and anti-P3 sera and weakly with anti-IV Col serum. In diabetic nephropathy, anti-HGBM serum stained the GBM in a double linear distribution without reacting with the expanded mesangium; anti-IV Col serum stained the mesangium and the GBM in a less clear double linear fashion while anti-P3 serum stained the GBM as single line. Thin membrane disease and Alport's syndrome had normal reactivity with all antisera. However, in one case of Alport's syndrome anti-HGBM and anti-P3 sera stained the GBM in a focal and segmental pattern, while normal staining with anti-IV Col serum was found. In lesions with adhesions and crescents the staining was positive for HGBM and IV Col and negative for P3; obsolescent glomeruli were stained with anti-HGBM and anti-P3 sera, and had diminished staining with anti-IV Col serum. The identification of the various structural glomerular antigens is useful in the classification of certain types of glomerular diseases. Further insight into the mechanisms underlying these conditions may be obtained in this way.

The dc dielectric strength of uniaxially drawn polyethylene terephthalate (PET) film has been investigated under compressive stresses. The drawn samples are heat-set in a silicone oil bath over a temperature range from 100 to 220°C for durations of 1 and 60 min in order to control the degree of crystallinity of the samples. The dc dielectric strength under no mechanical stress is found to increase with heat-setting temperature regardless of the heat-setting time. The compressive stress value showing maximum dielectric strength under compression has decreased significantly with increase in the heat-setting time and heatsetting temperature. The results obtained are discussed in terms of the morphological and mechanical properties of the samples.

Results of an experimental study on the DC breakdown characteristics of liquid helium and nitrogen in the presence of thermally created bubbles are presented. These results show that the bubble shape is affected significantly by the application of an electric field, and that the breakdown voltage depends closely on the bubble shape and decreases down to the breakdown voltage of gas at the normal boiling temperature or lower voltages. >

La resistance diminue quand augmente la teneur en ion jusqu'a 5 mol% (reticulation de petits agregats ioniques)

The dc dielectric strength of heat-treated biaxially drawn polyethylene terephthalate (PET) is studied under mechanical stresses. The sample is prepared on films with a draw ratio of 3.3x3.9 obtained by a continuous process. To study the effect of crystallinity on the dielectric strength, the sample that is held to constant size is annealed for durations of 1 and 60 min in a silicone oil bath maintained at a fixed temperature within ±2°C. The annealing temperature range is from 100 to 2200C. The maximum dielectric strength of the sample under no mechanical stress is found to occur at an annealing temperature of about 1400C. But the compressive stress showing maximum dielectric strength under compressive stress increases with the annealing temperature, and its value is not significantly varied by the cooling process after annealing. Compared with undrawn and uniaxially drawn PET, the biaxially drawn sample has good mechanical properties and dielectric strength characteristics under mechanical stresses. However, it is believed that the best annealing condition should be decided by the requirements for the electrical and mechanical characters of the sample.

The force acting on a corona wire was investigated experimentally to understand quantitatively the driving force causing wire vibration in electrostatic precipitators. The force consists of three components; (i) the electrostatic force, (ii) the reactive force induced by the electric wind and (iii) the Coulombic force due to space charges. The two latter forces are opposed to the former and the sum of these is called the repulsive force. It was found from experiments that the repulsive force increased proportionally to the applied voltage above the corona onset voltage and to the wire displacement up to 0.4 S from the centre of two plates of separation 2 S . Moreover, an empirical formula of the repulsive force per unit length of wire, f r , was derived as a function of line corona current densities, j 1 and j 2 , measured at each plate and the dimensions of the electrode system including the two-plate separation, the wire diameter, d , and the wire displacement, X , i.e. f r = A 0 √ d [{( S − X ) j 1 } 0.8 − {( S + X ) j 2 } 0.8 ] (N/m), where A 0 is a constant depending slightly on the effective wire length. The repulsive force becomes stronger than the electrostatic force and is a dominant component in the driving force causing the wire vibration as the applied voltage is raised beyond about 1.2 times that of the corona onset voltage.

It has been proved that the similarity law holds in ion flow electrification phenomena under d.c. transmission lines. The results obtained for a given size of object and electric field strength can therefore be extended to any size of object and for any field strength by this law. The stored energy on an insulated spherical or spheroidal object and the amount of the leakage current from a grounded object have been calculated. It is found that the stored energy is severe enough for electrostatic shocks but the value of the leakage current is less important than that of the short-circuit current under a.c. transmission lines.

Autologous immune complex nephritis (Heymann nephritis) is mediated by the autoimmune mechanism and can be induced in certain rat strains by immunization with tubular brush border antigen (Fx1A). The present study was undertaken as a tentative approach to prevent this nephritis, by daily intraperitoneal injections of the solubilized Fx1A for the purpose of removing free antibody from the circulation. Administration of solubilized Fx1A was started a week after the immunization for the induction of Heymann nephritis and continued until the animals were sacrificed at 14 weeks. A control group of immunized animals, also observed for 14 weeks, received saline. The injections of the solubilized FX1A decreased the incidence of proteinuria, the amount of immunoglobulin and complement depositions in the glomeruli, and also the titer of antibody against the brush border. It is concluded that the administration of the solubilized antigen exerts a preventative effect on the course of Heymann nephritis, probably due to removing the antibody from the circulation.

This report describes induction of nephritis, which was concurrently mediated by [anti-glomerular basement membrane antibody (anti-GBM) and anti-brush border antibody, in the Wistar rat immunized with a solubilized renal antigen (S-RA). The antigen was prepared by digestion of rat cortical tissue with trypsin and pronase. Ouchterlony test using antisera to the rat GBM and brush border showed that the S-RA contained both antigens. From the S-RA the brush border antigen was isolated by affinity chromatography. At the 8th week rats injected with the S-RA showed a linear or combined linear and granular distribution of rat IgG and C3 along the GBM in immunofluorescence. The capillary granular pattern was only observed at the 16th week. In contrast rats injected with the brush border antigen remained in a capillary granular pattern throughout the experimental course. It was suggested that the rat nephritis injected with the S-RA was mediated by the antibodies capable of reacting with at least two different antigens, namely the GBM and the brush border. The possibility was confirmed by demonstrating the coexistence of these two kinds of antibodies in the serum and kidney eluate from the nephritic rats.

In this report, the authors describe a case of a 2-year, 11-month-old girl with glomerulonephritis and no family history of renal diseases and deafness. Immunofluorescent studies in the renal biopsy specimens with the use of anti-sera against human glomerular basement membrane (GBM) and P3 antigen (prepared from bovine GBM and inducible of Steblay’s type nephritis in rats) demonstrated focal and segmental distribution of the GBM antigen(s). Electron microscopic examination revealed splitting and thinning of the GBM. Indirect immunofluorescence showed that there was no binding of Goodpasture’s anti-GBM antibodies to the glomeruli. These findings are similar to those in patients with hereditary nephritis. The immunofluorescent examination of the fixation of the various anti-sera, including anti-types IV and V collagens, laminin, fibronectin, and actomyosin sera on the GBM, revealed normal reactivity. The abnormalities observed in this case may be a part of the spectrum of primary GBM defects.

In an attempt to reproduce “glycoprotein nephritis”, nephritogenic glycoprotein or glycopeptides were prepared from isologous renal cortices by the method of Shibata et al. Rats of Wistar Imamichi that were given a single injection with glycoprotein or glycopeptides in incomplete Freund's adjuvant (IFA) to the hind footpads developed glomerulonephritis. Light microscopic findings were essentially similar to those in their reports. However, in spite of similar materials and methods as they used, immuno-fluorescent findings were entirely different; localization of rat IgG and complement showed a “linear pattern” in contrast to their “mesangial pattern.” Linear pattern in immunofluorescent study supports a notion that we succeeded in induction of autoimmune anti-glomerular basement membrane glomerulonephritis (Steblay's type nephritis) by immunization with isologous renal antigen.

Commonly shared antigens between the renal tissue and lymphocytes, especially the thymocyte were studied In rats by immunofluorescent technique. To clarify the specificity of antisera, absorption analysis was carried out. The brain-associated thymocyte antigen, presumably Thy 1 antigen, was detected by anti-rat thymocyte serum (ATS) or anti-rat brain serum (ABS) not only on the surface of thymocytes but also in renal glomeruli. The distribution or localization of the antigen in glomeruli was considerably different between acetone-fixed and unfixed kidney sections. On the fixed section the antigen was shown exclusively in the glomerular mesangium. However, it appeared to be diffusely dispersed on glomerular tissue on the unfixed section. On the other hand, antisera against kidney-related antigens, anti-Fx1A, anti-GBM, and anti-CIG, did not react with the surface of thymocytes, or they were not absorbed with brain homogenate. ACTA PATHOL. JPN. 32: 483∼489, 1982.

This paper describes a simple production method for carbon nanoparticles by pulsed arc discharge in water, which is triggered by the electrical breakdown of water between graphite electrodes. High-resolution transmission electron microscopy (HRTEM) observation revealed that the main products obtained by the proposed method were onion-like nanoparticles; while carbon nanotubes were not formed. The carbon nanoonions uniformly dispersed in water forming micron-sized aggregates. The effects of the arc discharge mode (dc or pulse) on the nanoparticle formation mechanism are discussed.

Partial discharge (PD) characteristics within an artificial air-filled void contained in a solid insulator were experimentally investigated under 60 Hz ac voltages at liquid nitrogen temperature (77 K) and room temperature of 298 K. The results show that the first PD inception voltage at 77 K is about twice higher than that at 298 K while successive values at both temperatures are almost the same. The results also show that PD charge magnitude noticeably decreases and PD pulse number remarkably increases with the decrease in the temperature from 298 K to 77 K. The latter results are further discussed based on the observed remarkable decrease in the charged area by a single PD on an inner void surface with the decrease in the temperature.

Degradation and lifetime characteristics of solid insulators with an artificial air-filled void were investigated experimentally at liquid nitrogen temperature. As a result, it was found that the lifetime of a test sample decreased suddenly with increase in applied voltage. Observation of the PD characteristics showed that the decrease in lifetime at a higher applied voltage had a close relationship with the PD activity. The void surface subjected to the PDs was observed with SEM, and the degradation mechanism was discussed taking the experimental results into consideration.

This paper discusses the importance of the consideration of the electrical gradient force (or dielectrophoretic force) which has not been adequately considered in the particle deactivation methods in Gas Insulated System (GIS). The particle motion on bare and coated electrode in the presence of the electrical gradient force is investigated under DC voltage in atmospheric air. On the basis of the obtained results, the effectiveness of the particle traps installed on the spacer surface and in the grounded electrode is confirmed experimentally.

Corona discharge mechanism based on corona current pulse characteristics from a metallic floating particle was investigated in SF 6 gas under DC voltage as a basis for clearly understanding of corona discharge mechanism in SF6 gas gap with floating particle under AC voltage. Corona behavior and breakdown voltage were investigated by changing the particle position in the gap. It shows that active development of corona and local minimum in breakdown voltage characteristic were observed when the particle is in the vicinity of the electrode due to local arc bridges intermittently the minor gap between the particle and electrode. However, it is obscure as compared with the one in air gap, where the breakdown fell to corona onset voltage

This paper deals with free-conducting particle motion and particle-triggered breakdown mechanism in AC and DC electric fields between nonparallel plane electrodes. Particle motion is divided into several modes, and particle-triggered breakdown mechanisms are discussed for each motion mode theoretically and experimentally. The obtained results suggest that several types of particle-triggered breakdown can occur in gas insulated system.

This paper deals with breakdown voltage characteristics of saturated liquid helium, in the presence of a metallic particle in shape of needle or sphere to obtain insulation design data for the pool-cooled low temperature superconducting coil and to find the factors dominating the breakdown voltage. The results show that the lowest breakdown voltage appears at a free needle particle which produces bubble-generation, rich initial electrons and high stress electric field.

Dielectrophoresis (DEP) is the electrokinetic motion of dielectrically polarized particles in nonuniform electric fields. DEP has found many useful technological applications including separation, levitation and characterization of dielectric particles such as biological cells. In this study, the authors propose a new type of liquid filter, which utilizes dielectrophoretic force (DEP force) to capture fine particles suspended in liquid. The DEP filter consists of an electrode system that is filled up with many dielectric particles. These particles modify the electric field distribution in the electrode system so that strong DEP force is generated on their surfaces. If the DEP force is stronger than drag force exerted by liquid flow in the filter, the suspended particles can be trapped and eliminated from the flowing liquid. The DEP filter can control trapping and releasing process just by changing electrode energizing AC signal and the resultant DEP force. It was experimentally confirmed that the DEP filter could continuously eliminate yeast cells suspended in water. The cell density decreased from 10/sup 6/ cells/mL to 10/sup 1/ cells/mL in about an hour. The electrical conductivity of the medium was a crucial parameter that influenced the liquid temperature by Joule heating and DEP force. Furthermore, the selective separation of viable and nonviable yeast cells was demonstrated by utilizing viability dependency of the DEP force.

An inductive energy storage pulsed power generator needs an opening switch to immediately limit the circuit current and to achieve a high inductive voltage. Quench phenomena of a superconducting wire can be applicable to the opening switch because it provides a fast resistance increase of the wire. In this study, quench characteristics of a superconducting wire were investigated using pulsed current waveforms with various peak values. It has been found that quench of the wire occurred when the current exceeded a critical value. The resistance rise rate of the wire increases with the current: peak and wire length. An inductive pulsed power generator, which used a solenoid coil of the superconducting wire as an opening switch, was constructed to demonstrate that the switch could principally work to generate pulsed voltage and power with a fast rising rate.

Ionomeres(polydimethylaminostyrene quaternarise avec le bromo-1 ethane) ou les groupes ioniques sont localises seulement aux extremites de chaine