Showing papers by "Mitsubishi published in 1989"

Stacked-type semiconductor device

Abstract: In a method of manufacturing a stacked-type semiconductor device, firstly, a first semiconductor substrate having a first device formed thereon is covered with an interlayer insulating layer and a planarized polycrystalline silicon layer is formed on the interlayer insulating layer. The first semiconductor substrate and a second semiconductor substrate are joined together by putting the surface of the polycrystalline silicon layer in close contact with the surface of a refractory metal layer formed on the second semiconductor substrate, applying thermal treatment at 700° C. or below and changing the refractory metal layer to silicide.

Multimedia data transmission system

Abstract: A vector quantizer which transmits the input vector of the time when the minimum distortion is larger than the preset distortion threshold value and stores such input vector into the second code book as the new quantizing representative vector for the use in the successive vector quantizing processes. Further, since the first and second code book constitute in the form of tree-structure, calculation for search may be executed at a high speed.

Identification of a gene conferring resistance to zinc and cadmium ions in the yeast Saccharomyces cerevisiae

Abstract: A DNA fragment conferring resistance to zinc and cadmium ions in the yeast Saccharomyces cerevisiae was isolated from a library of yeast genomic DNA. Its nucleotide sequence revealed the presence of a single open reading frame (ORF; 1326 bp) having the potential to encode a protein of 442 amino acid residues (molecular mass of 48.3 kDa). A frameshift mutation introduced within the ORF abolished resistance to heavy metal ions, indicating the ORF is required for resistance. Therefore, we termed it the ZRC1 (zinc resistance conferring) gene. The deduced amino acid sequence of the gene product predicts a rather hydrophobic protein with six possible membrane-spanning regions. While multiple copies of the ZRC1 gene enable yeast cells to grow in the presence of 40 mM Zn2+, a level at which wild-type cells cannot survive, the disruption of the chromosomal ZRC1 locus, though not a lethal event, makes cells more sensitive to zinc ions than are wild-type cells.

Detection of a new circumstellar carbon chain molecule, C4Si

Abstract: A new interstellar carbon chain molecule, C4Si, has been detected in the envelope of the evolved star IRC + 10216. This molecule is the carrier of six unidentified lines which had been detected during the molecular line survey at Nobeyama Radio Observatory. The identification was made through astronomical detections followed by quantum chemical calculations and laboratory spectroscopic experiments. The rotational constant and the centrifugal distortion constant were B(0) = 1533.77206(146) MHz and D(0) = 0.00005827(35) MHz, respectively, where the numbers in parentheses represent one standard deviation in units of the last significant digits. The rotation temperature and the column density were 15 + or - 2 K and (7 + or - 1) x 10 to the 12th/sq cm, respectively, assuming a source size of 25 arcsec.

Effect of MCI-186 on brain edema in rats.

Abstract: We induced brain edema in 72 rats by injecting 5 microliters of 3.0% wt:vol polyvinyl acetate into the left internal carotid artery, producing permanent embolization in the left cerebral hemisphere, which developed ipsilateral brain edema reproducibly. Edema was assessed 24 hours after embolization by determining the brain water content and the sodium and potassium concentrations. In this model, the free radical scavenger MCI-186 at 1.0 and 3.0 mg/kg i.v. prevented brain edema in a dose-dependent manner. At 3.0 mg/kg i.v., MCI-186 significantly reduced water content by 1.5% and improved the sodium-potassium balance to within the normal range in the embolized left hemisphere. Dexamethasone at 1.0 mg/kg i.v. did but at 3.0 mg/kg i.v. did not significantly inhibit the development of brain edema. Indomethacin at 4.0 mg/kg i.p. had no effect on brain edema. We suggest that the cyclooxygenase metabolites of arachidonic acid liberated from neuronal cell membrane phospholipids are not likely to be involved in the pathogenesis of permanent brain edema induced by polyvinyl acetate. Our results suggest that MCI-186 attenuates brain edema by suppressing the production of lipoxygenase metabolites, including free radicals or lipid peroxides, and that it may prove valuable for the treatment of brain edema associated with cerebral ischemia.

Dynamic semiconductor memory device of a twisted bit line system having improved reliability of readout

Abstract: An arrangement for providing a compensation of capacitance coupling between word lines and bit lines in a memory structure including twisted bit lines. Two dummy word lines maintained at a predetermined potential are formed at a twisted portion of a pair of bit lines. Dummy cells are provided at respective twisted portions of the dummy word lines and the bit lines. A plurality of word lines are formed in a direction intersecting with the bit lines and the word lines are divided into four word line groups according to positions of the twisted portions of the bit line pairs. When an arbitrary word line is selected, a potential of at least one dummy word line corresponding to the word line group to which the selected word line belongs is lowered. Consequently, the rise of the potential of the bit lines caused by the selection of the word line is compensated for by the lowering of the potential of at least one dummy word line, making it possible to decrease errors in reading. Particular cell layer arrangements simplify increase in integration density in the combination of dummy cell compensation with the twisted bit line balancing of capacitance coupling.

Nitrification rates and 15 N abundances of N 2 O and NO 3 − in the western North Pacific

Abstract: NITROUS oxide plays an important part in atmospheric chemistry; it is a 'greenhouse' gas and has the potential to destroy ozone. Concentrations of N2O in surface waters of the oceans are generally close to equilibrium with the atmosphere, but sub-surface sea water is supersaturated with N2O1–5. The oceans are now regarded as a source4 for atmospheric N2O by production through the oxidation of ammonium ('nitrification')1,3, except in extremely oxygen-deficient waters6. Nevertheless, the possibility that N2O might be produced through the reduction of nitrate ('denitrification') cannot be ruled out5,7. The distribution of 15N in atmospheric and oceanic N2O can be used to investigate the behaviour of N2O in the oceans8,9. Here we report simultaneous measurements of the nitrification rates and nitrogen isotope data for N2O and NO3– produced in the western North Pacific Ocean. The amount of N2O produced by nitrification is much lower than that expected from the production of NO3–. The N2O in the oxygen-deficient layer is more enriched in 15N than NO3–. These results imply that the contribution of nitrification to the production of N2O is lower than previously thought and that denitrification is primarily responsible for the production of N2O.

Shape memory polymer foam

Abstract: A shape memory polymer foam which takes on a deformed shape and an as-molded shaped, said deformed shape being produced when the polymer foam is compressed at a temperature higher than the glass transition point (Tg) of the polymer and then kept compressed at a temperature lower than the Tg until compression sets, said as-molded shape being produced when the compressed polymer foam is heated again to a temperature higher than the Tg until it recovers its original shape.

Shape memory polyurethane elastomer molded article

Abstract: A shape memory polyurethane elastomer molded article formed from a polyurethane elastomer which has a degree of crystallinity of 3∼50 wt%, contains approximately equal amounts of [NCO] groups and [OH] groups at the terminals of the polymer, and is polymerized by the prepolymer method from a difunctional diisocyanate, a difunctional polyol, and a difunctional chain extender containing active hydrogen groups, which are formulated in a molar ratio of diisocyanate : polyol : chain extender = 2.00∼1.10 : 1.00 : 1.00∼0.10, preferably 1.80∼1.20 : 1.00 : 0.80∼0.20. It is capable of melt molding such as injec­tion molding, extrusion molding, and blow molding, and ean be manufactured freely without being restricted by the shape of the molded article.

Cognition device for battery residual capacity

Abstract: In a cognition device for battery residual capacity, battery voltage information and battery ambient temperature information are input to a microprocessor through an A/D converter. In the microprocessor, the voltage information is corrected with load information; the data conforming to the ambient temperature information are read out of the battery discharge characteristic data which are previously stored in memory, and the readout data are compared with the corrected voltage information so that the battery residual capacity can be computed from the result of the above comparison data. In this arrangement, it is therefore possible to accurately recognize battery residual capacity at an arbitrary point in time.

Apparatus for forming thin film

Abstract: Apparatus for forming a thin film on a substrate surface by a CVD (Chemical Vapor Deposition) method which includes diffusing pipes for diffusing and supplying a first reactive gas, and uniformizing plates for supplying uniformly an active species formed through excitation of a second reactive gas The first reactive gas and the active species are mixed uniformly with each other, and the resultant uniform mixture is supplied uniformly to the substrate surface, whereby a uniform film deposition rate is obtained in a reaction zone in which the thin film is formed, and a uniform thin film is formed over the entire substrate surface even when the area of the substrate surface is large

Mobile telephone device with low power consumption

Abstract: A mobile telephone device comprises a separate paging signal channel in addition to the conventional transceiver channels which process voice signals The paging signal channel has a lower power consumption level than the transceiver channels A power supply control device shuts off power to the conventional transceiver channels when in a standby mode, ie when waiting for an incoming call, and applies power to the paging signal channel instead Therefore, power consumption is reduced in the standby mode and consequently, the operating time of the battery is extended Power is applied to the transceiver channels during voice communication periods A calling party's telephone number received in the paging signal channel is stored and displayed A control unit has the capability of immediately returning the calling party's call from the telephone number so stored and displayed

Method of resin sealing semiconductor devices

Abstract: A method of resin sealing semiconductor devices wherein semiconductor devices, such as semiconductor chips, are placed in cavities provided in a pair of chase blocks which are clamped by a press machine through support members capable of elastic compressive deformation. Plastic is then injected into the cavities of the chase blocks to resin seal the semiconductor devices.

Shape memory film

Abstract: A shape memory film formed from a shape memory transparent polymer, said shape memory film being capable of remembering a basic shape such as plane configuration and dead folds, taking on a second shape when the basic shape is modified (by changing the plane configuration and adding dead folds, twists, three-dimensional configurations, etc.) at a temperature higher than the glass transition point of the polymer and lower than the molding temperature of the polymer, and having the second shape set when cooled to a temperature lower than the glass transition point while being kept in the second shape; and a method of using said shape memory film by setting the second shape and subsequently heating the film to a temperature higher than the glass transition point, thereby causing the film to restore its basic shape.

Electronic device housing with temperature management functions

Abstract: The electronic device housing employs unique temperature management functions. Thermally sensitive electronic components are thermally isolated from the environment and from temperature generating components provided within the housing through the use of an insulative case material. Furthermore, heat generating components are connected to the outside environment with a conductive thermal path which is isolated from the remaining components provided within the case, thereby efficiently transferring undesired heat to the environment without allowing the heat to substantially affect remaining components in the housing. The electronic device housing includes a case and a cover formed by molding using a synthetic resin, and a metallic layer formed on the surface of the case which cooperates with the cover to provide an electromagnetic shield for the case. Further, a waterproof seal is provided in the abutment between the case and the cover and the heat radiating effect of the case is enhanced by a heat radiation plate provided outside the case and connected to any heat generating components. The electronic device of such construction is easy to machine, light in weight and inexpensive.

Solid electrolytic capacitor

Abstract: PROBLEM TO BE SOLVED: To increase capacitance and moreover reduce impedance at a high frequency region by a method, wherein this capacitor is composed of a conductive high polymer in which alkylsulfonate ions are doped in a high polymer having a heterocyclic monomer unit represented by a specific formula as a repetition unit. SOLUTION: A porous tantalum sintered body is anode-oxidized to form a dielectric film composed of a tantalum oxide on the surface. Next, after a tantalum sintered body formed with the dielectric film on the surface is dipped in a hydrogen peroxide solution and a vihiolic aqueous solution, it is taken out, and a high polymer film having a heterocyclic monomer unit as the repetition unit represented by a formula [R1, R2 are each independently an alkyl base or H, and X is S or NR3 (R3 is an alkyl base or H)] is formed on the dielectric film. Dodecylsulfonate ions and vitriolic ions are doped on the high polymer film to form a solid electrolytic layer composed of a conductive high polymer.

Process for producing highly water absorptive polymer

Abstract: A process for producing a highly water-absorbing polymer, which comprises treating a water-absorbing polymer containing a carboxyl group and/or a carboxylate group with a silane coupling agent in the presence of water.

Central administration of muscimol phase-shifts the mammalian circadian clock.

Abstract: The suprachiasmatic nucleus (SCN) of the hypothalamus contains a neural oscillatory system which regulates many circadian rhythms in mammals. Immunohistochemical evidence indicates that a relatively high density of GABAergic neurons exist in the suprachiasmatic region. Since intraperitoneal injections of the benzodiazepine, triazolam, have been shown to induce phase shifts in the free-running circadian rhythm of locomotor activity in the golden hamster, the extent to which microinjections of muscimol, a specific agonist for gamma-aminobutyric acid (GABA), may cause phase-shifts in hamster activity rhythms was investigated. Stereotaxically implanted guide cannulae aimed at the region of the SCN were used to deliver repeated microinjections in individual animals. A phase-response curve (PRC) generated from microinjections of muscimol revealed that the magnitude and direction of permanent phase-shifts in the activity rhythm were associated with the time of administration. The PRC generated for muscimol was characterized by maximal phase-advances induced 6 h before activity onset and by maximal phase-delays which occurred 6 h after activity onset. The PRC for muscimol had a shape similar to a PRC previously generated for the short-acting benzodiazepine, triazolam. Single microinjections of different doses of muscimol given 6 h before activity onset induced phase-advances in a dose-dependent fashion. Histological analysis revealed that phase shifts induced by the administration of muscimol were associated with the proximity of the injection site to the SCN area. These data indicate that a GABAergic system may exist within the suprachiasmatic region as part of a central biological clock responsible for the regulation of the circadian rhythm of locomotor activity in the golden hamster.

Device for accelerating and storing charged particles

Abstract: A device for accelerating and storing charged particles of the present invention comprises a vacuum duct which has two opposite linear portions and two opposite curved portions respectively connected to the linear portions and which functions to maintain the orbit of revolution of the charged particles in a vacuum; an accelerating device for accelerating charged particles which is disposed on the orbit of the charged particles; a pair of bending magnets which are respectively disposed on the curved portions of the vacuum duct; and a pair of quadrupole electromagnets which are respectively disposed on the linear portions of the vacuum duct and at least one of which is disposed at a position at a given distance from the center of the corresponding linear portion.

A method for finding a pair of multiple load flow solutions in bulk power systems

Abstract: The authors discovered that the convergent characteristic of load flow calculation by the Newton-Raphson method in rectangular coordinates has a unique linearity. It tends to converge straight toward two multiple solutions when they are located close to each other. On the basis of this feature, the authors propose a method for solving two close solutions in bulk power systems. The results of applying this method to a heavily loaded practical 233-bus system and the Klos-Kerner 11-bus system verify its robustness and ability to find solutions successfully and quickly. The proposed method is so fast that it can be applied to an online voltage security system. >

Method for producing a three-dimensional type semiconductor device

Abstract: A method for producing a three-dimensional type semiconductor device comprises a first semiconductor integrated circuit layer comprising active regions, insulating layers, gate electrodes, and interconnection layers; an insulating layer formed thereon; and a second semiconductor integrated circuit layer comprising active regions, insulating layers, gate electrodes and interconnection layers. Active regions in the second layer are directly coupled to an interconnection layer, and active region and a gate electrode in the first layer, which are located immediately thereunder, by interlayer interconnections through a contact hole formed straight, so that a distance of each interlayer interconnection can be reduced.

Twisted bit-line architectures for multi-megabit DRAMs

Abstract: As the memory cell array of DRAM has been scaled down, inter-bit-line coupling noise has emerged as a serious problem. The signal loss due to this noise is estimated at about 40% of the signal amplitude in a polycide-bit-line 16-Mb DRAM with a technologically attainable scaling scheme. Twisted bit-line architectures to reduce or eliminate the noise are proposed and demonstrated by the soft-error rate improvement of a 1-Mb DRAM. The effective critical charge is improved by 35%, which is attributed not only to the improvement of the signal amplitude but also to the elimination of large coupling noise during the sensing operation. The impact of these twisted bit-line architectures from a scaling viewpoint is also examined, and they are shown to be promising candidates for overcoming the scaling problems of DRAMs. >