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The differences in rorqual feeding ecology have been linked to the presence of different morphological markers. The Antarctic minke whale (Balaenoptera bonaerensis Burmeister, 1867) and the common minke whale (Balaenoptera acutorostrata Lacepede, 1804) are closely related species, but their morphological differences have not been fully investigated. In this study, we compared 21 skull and 11 feeding apparatus (baleen and mouth-related parts) measurement points between these two species using hundreds of individuals covering a wide range of body lengths in both sexes. Their engulfment capacities were estimated using these measurements. Our results show that Antarctic minke whales have (i) proportionally larger skulls to the body length, (ii) more dorsoventrally and laterally curved rostra, (iii) proportionally larger feeding apparatuses to the condylobasal length, and (iv) significantly larger engulfment capacity than common minke whales. These differences could indicate that Antarctic minke whales have developed a feeding strategy suitable for feeding on krill, which forms large schools. In contrast, common minke whales have adapted to prey on small pelagic fishes that are agile and form small schools. Key words: Balaenoptera bonaerensis, Balaenoptera acutorostrata, Antarctic minke whale, common minke whale, skull morphology, feeding morphology, engulfment capacity. Les differences sur le plan de l'ecologie de l'alimentation chez les rorquals ont ete associees a la presence de differents marqueurs morphologiques. Bien que le rorqual antarctique (Balaenoptera bonaerensis Burmeister, 1867) et le petit rorqual (Balaenoptera acutorostrata Lacepede, 1804) soient des especes etroitement reliees, leurs differences morphologiques n'ont pas ete examinees de maniere exhaustive. Nous avons compare 21 et 11 mesures du crane et de l'appareil d'alimentation (fanons et parties buccales), respectivement, obtenues de centaines de specimens des deux especes couvrant une grande fourchette de longueurs du corps pour les deux sexes. La capacite d'engouffrement a ete estimee a la lumiere de ces mesures. Nos resultats montrent que les rorquals antarctiques ont (i) des cranes proportionnellement plus grands par rapport a la longueur du corps, (ii) des rostres a plus forte courbure dorsoventrale et laterale, (iii) des appareils d'alimentation proportionnellement plus grands par rapport a la longueur condylobasale et (iv) une capacite d'engouffrement significativement plus grande que les petits rorquals. Ces differences pourraient indiquer que les rorquals antarctiques ont developpe une strategie d'alimentation adaptee a la consommation de krill, qui forme de grands bancs, alors que les petits rorquals se sont adaptes a la consommation de petits poissons pelagiques agiles formant de petits bancs. [Traduit par la Redaction] Mots-cles : Balaenoptera bonaerensis, Balaenoptera acutorostrata, rorqual antarctique, petit rorqual, morphologie cranienne, morphologie de l'appareil alimentaire, capacite d'engouffrement., Introduction Feeding is one of the most fundamental aspects for any animal species, as it is directly tied to their survival. Each cetacean species has its own feeding ecology (i.e., [...]

We propose using zeolite filter in portable processing equipment to separate and recover S[F.sub.6] from S[F.sub.6]/[N.sub.2] mixtures. Testing of a prototype filter has shown that S[F.sub.6] is completely adsorbed by the filter, and the exhaust gas from the filter is pure [N.sub.2] (i.e., at an undetectable level of S[F.sub.6] measured by a gas chromatograph). The S[F.sub.6] fraction of the sorbate phase (solid phase) has been evaluated from the tests, and it is a high fraction as expected. For example, 70% sorbate corresponding to processing a mixture of 5% S[F.sub.6], and 83% sorbate corresponding to processing a mixture containing 10% S[F.sub.6]. The process of releasing the S[F.sub.6] from the filter and renewing the filter by thermal swing adsorption (TSA) technique has also been investigated to determine a commercial operating temperature of 150 [degrees] C. The feasibility of applying this new concept in a portable S[F.sub.6]/[N.sub.2] mixture processing equipment is discussed and compared with an alternative system that the authors developed previously which was based on pressure swing adsorption (PSA) technique and also using zeolite. Index Terms--Adsorption, green house effect, S[F.sub.6]/[N.sub.2] mixture, S[F.sub.6] recovery, zeolite.

This paper describes the results of tests and discussions carried out to develop a system for monitoring partial discharges generated in GIS. They include the propagation characteristics and the mechanisms of partial discharge pulses in the GIS, the results of computer simulation, and the results of comparisons with previous tests to verify the partial discharge locating method.

This paper describes detection and diagnostic techniques for partial discharges in GIS. Partial-discharge current waveforms of SF(sub 6) gas and external noise characteristics of actual substations were investigated, and a measuring system having sensors in GIS and employing frequency range of VHF band was developed. By this system, detecting very small partial discharges of several 10 pC level has become possible. Also, a neural network system, focusing attention as a method for recognizing patterns, was applied for determining causes for partial discharge in GIS, and its applicability has been proved.

This paper deals with the results of field tests carried out to develop an on-line sensor for monitoring partial discharges generated in the GIS. It covers noise distribution in the GIS tank, the propagation of partial-discharge pulses, and its mechanisms, while presenting applications of partial-discharge on-line monitoring sensors.

This paper deals with the results of various insulation fault simulation tests with a 300kV GIS installed in the field. It covers the levels and patterns of partial discharges generated by various faults and levels to be detected in the field.

This paper deals with the impulse breakdown characteristics of insulation models simulating static shields for coil ends of [SF.sub.6] gas-insulated transformers. The static shield is composed of a double-covered electrode and a filler between the coverings. If a filler made of elastomer material is fitted closely on the covered electrode to eliminate gas gaps between the filler and the covered electrode, the impulse breakdown voltage of the static shield is higher than with gas gaps. If a low-permittivity filler is used, the impulse breakdown voltage of the static shield is still higher. The breakdown voltage here can be explained by considering that the breakdown is caused by small gas gaps between the filler and the covered electrode. The dielectric strength of the coil end can be inereased by applying a static shield with an elastomer filler.

Syntheses of LDH (layered double hydroxides) substituted with [Fe.sup.3+] and [Ni.sup.2+] were attempted by a co-precipitation method and their products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and X-ray absorption fine structure (XAFS). XRD and FT-IR results indicated that obtained products were composed of a single phase of LDH with C[O.sup.2-.sub.3] anions at interlayer, suggesting the successful syntheses of various modified LDH, Mg-Fe/LDH and Ni-Fe/LDH. In addition, XAFS measurements of Mg-Fe/LDH indicated that substituted [Fe.sup.3+] located at octahedral site in LDH structure. For the application to water purification, these modified-LDH substituted with [Fe.sup.3+] and [Ni.sup.2+] as an adsorbent material were used for the magnetic separation system. As a results, these modified-LDH possessed the higher removal ability for As ions than ordinary Mg-Al/LDH and FeOOH, and furthermore were able to collect with high gradient magnetic separations. In addition, after As removal the existence conditions of As ions in LDH were examined by XANES. Index Terms--Crystal microstructure, magnetic materials, magnetic separation, nanostructured materials.

Shed materials for hollow composite insulators (low temperature vulcanized (LTV) silicone rubber, high temperature vulcanized (HTV) silicone rubber, ethylene vinyl acetate (EVA) and ethylene propylene diene monomer (EPDM)) were examined through accelerated weathering tests and their weathering resistances were evaluated from changes of surface and bulk properties. For silicone rubber, changes in the content of low molecular weight (LMW) silicone (silicone oil) related to maintaining water repellency were investigated. The results showed that silicone rubbers had excellent weathering resistance and kept high water repellency during long term weathering tests. Using an equivalent model, an investigation was also carried out on how non-soluble contaminations deposited on the surfaces of sheds in outdoor service could cut off UV rays.