Hitachi, Ltd.

Shin-kobe Electric Machinery Co., Ltd.

Other

Hitachi Metals, Ltd.

Kyoko Honbo

Masanori Sakai

Katsumi Mabuchi

Yasushi Muranaka

Yasuo Kondo

Akihiro Gotoh

Masahiro Kasai

Tokiyoshi Hirasawa

Yoshiji Hotta

Motoko Harada

Masayuki Terada

Takanori Yamazaki

Yoshiaki Nakamura

Seiji Takeuchi

Hideto Momose

Hirofumi Takahashi

Mina Amo

Daisuke Abe

Eiji Hoshi

This invention provides a magnetic recording medium excellent in terms of corrosion resistance. The magnetic recording medium comprises a magnetic recording layer, a protective layer and a lubricant layer provided on a nonmagnetic substrate, and the lubricant layer comprises a compound having a heterocyclic ring.

Magnetic recording media and magnetic recording system

Disclosed is a method for estimating, within a short time, the life of a cable insulating coating material containing an antioxidant in a suitable concentration based on the rate of decrease of the antioxidant and on the critical concentration of the antioxidant at which oxidative degradation rapidly proceeds. The method tests the coating material to examine its life, the coating material including a base polymer, and an antioxidant having a functional group suppressing an oxidative deteriorative reaction of the base polymer. The method includes performing a thermal degradation test on the coating material; determining the degradation levels and degradation rates of the coating material at two or more time points in the thermal degradation test, based on the ratio of the absorbance of the functional group of the antioxidant to the absorbance of the base polymer; and thereby evaluating the life of the coating material.

Method for evaluating life of cable insulating coating material

The present invention allows simple and sensitive detection of microimpurities, microdefects, and corrosion starting points which may be present in a material. A probe microscope has a function to sense ions diffused from a specimen in a liquid. A probe is caused to scan over a predetermined range on a specimen. Then, the probe is fixed to a particular position in a liquid so as to set the distance between the specimen and the probe to a given value at which the microstructure of the specimen surface cannot be observed. Thereafter, one of the current between the probe and a counter electrode and the potential between the probe and a reference electrode is controlled, and the other of the current and potential which varies in accordance with the control is measured. Thus, ions diffused from the specimen are sensed.

Probe microscope and measurement method using the same

A secondary battery comprises a single-plate lead acid battery (Va), a positive electrode capacitor layer and a negative electrode capacitor layer, which are formed on the respective surfaces of a positive electrode plate, and a negative electrode plate. Each of the positive electrode plate and negative electrode plate contains an active material, to have a configuration in which activated carbon has a concentration gradient. The electronic resistance between a collector terminal and the center of a portion where activated carbon is present at a high concentration is lower than the electronic resistance between the collector terminal and the center of a portion where activated carbon is present at a low concentration. In the single-plate lead acid battery, charges are accumulated in the positive electrode capacitor layer and in the negative electrode capacitor layer.

Energy conversion device

An object of the present invention is to take fundamental measures against the phenomenon that the positive current collector of a lead-acid battery elongates due to corrosion, in consideration of a mechanism, and to inhibit corrosion elongation. A current collector is prepared by the steps of: mixing a lead oxide of pinning compounds for inhibiting recrystallization with the atomized powder of lead or a lead alloy; and then powder-rolling the mixture. A lead-acid battery is composed with the use of the current collector.

Current collector of lead-acid storage battery, and lead-acid storage battery

A lead-acid battery superior in high-efficiency charging characteristic to conventional lead-acid batteries and a carbon material used in the lead-acid battery having excellent charge acceptability are disclosed. The lead-acid battery uses, as an additive to the anode active material, a simple substance and/or compound thereof, both having a catalysis for desulfurization or a catalyst for SOoxidation by adding to, or loading on, a carbon material such as active carbon, carbon black, or the like. When the lead-acid battery with an anode containing carbon material is applied to electric cars, various hybrid cars, power storage systems, elevators, electromotive tools and power source systems such as uninterruptible power source, distributed power source and the like, all having high input and output requirements, stable control can be obtained.

Lead-acid battery

A lithium secondary battery characterized by a high power capacity and a long service life has a negative electrode , a positive electrode and a non-aqueous electrolyte containing lithium salt. The lithium secondary battery is characterized by further comprising multiple oxide represented by a general formula Li Mn M Q O (where M denotes at least one element selected from among Ni, Fe, Co, Cu and Cr; Q denotes at least one element selected from among C, N, S, P, Si, F, Cl, I and Br; and x, a, b, c and d are within the range of 0&lE;x&lE;) 1.1, 0&lE;a&lE;0.5, 0.05&lE;b&lE;1.0, 0.000001&lE;c<0.05 and 0&lE;d&lE;0.1, respectively) as a positive electrode activator.

Positive electrode activator for lithium secondary battery and lithium secondary battery

A lithium secondary battery having a longer life than conventional battery at a high temperature for electric power storage and electric vehicles is obtained. A lithium secondary battery having a long life at a high temperature can be obtained by using a material specified in Li/Mn atomic ratio, lattice constant, half value width, specific surface area, and average primary particle size as the positive electrode active material; and a material specified in density.

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Hitachinaka, Japan

Kyoko Honbo