116 research outputs found

    Prediction Of Lateral Vibration Behavior Of Integrally Geared Centrifugal Compressor During Synchronous Motor Startup By Transient Torsional-Lateral Coupled Analysis

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    LectureStartup transients of both torsional and lateral vibration behaviors of an integrally geared centrifugal compressor driven by a synchronous motor are examined by transient torsional-lateral coupled analyses, and the numerical calculation results are evaluated using the field measurements as a benchmark. Since linear bearing coefficients are employed in the numerical simulation instead of more sophisticated nonlinear bearing model, bilinear stiffness is additionally considered to reflect the effects of the rotor confinement within the bearing clearance. Moreover, temporary teeth separation of the gear meshing and engagement at the backside during torque reversal is also considered in the numerical calculation. The transient lateral vibration behavior of the pinion rotor during the synchronous motor’s startup is successfully replicated. Both (a) bilinear stiffness of the pinion rotor bearings due to rotor restraint within the bearing clearance, and (b) effect of temporary teeth separation within the backlash and engagement at the backside because of torque reversal, are found to strongly influence the numerical predictions

    Experimental Evaluation of Mechanical Reliability of the Impeller Blade for Large Integrally Geared Compressors

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    Extended morphological processing: a practical method for automatic spot detection of biological markers from microscopic images.

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    BACKGROUND: A reliable extraction technique for resolving multiple spots in light or electron microscopic images is essential in investigations of the spatial distribution and dynamics of specific proteins inside cells and tissues. Currently, automatic spot extraction and characterization in complex microscopic images poses many challenges to conventional image processing methods. RESULTS: A new method to extract closely located, small target spots from biological images is proposed. This method starts with a simple but practical operation based on the extended morphological top-hat transformation to subtract an uneven background. The core of our novel approach is the following: first, the original image is rotated in an arbitrary direction and each rotated image is opened with a single straight line-segment structuring element. Second, the opened images are unified and then subtracted from the original image. To evaluate these procedures, model images of simulated spots with closely located targets were created and the efficacy of our method was compared to that of conventional morphological filtering methods. The results showed the better performance of our method. The spots of real microscope images can be quantified to confirm that the method is applicable in a given practice. CONCLUSIONS: Our method achieved effective spot extraction under various image conditions, including aggregated target spots, poor signal-to-noise ratio, and large variations in the background intensity. Furthermore, it has no restrictions with respect to the shape of the extracted spots. The features of our method allow its broad application in biological and biomedical image information analysis

    Selective syntheses of leuconolam, leuconoxine, and mersicarpine alkaloids from a common intermediate through regiocontrolled cyclizations by Staudinger reactions

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    Selective syntheses of leuconolam, leuconoxine, and mersicarpine alkaloids bearing distinctive core structures were achieved through Staudinger reactions using a common intermediate. In the key cyclization step, water functioned like a switch to control which core structure to produce. The chemistry allowed for selective syntheses of the group of alkaloids from a simple intermediate through straightforward chemical operations

    Experimental Evaluation of Mechanical Reliability of the Impeller Blade for Large Integrally Geared Compressors

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    Lectur

    Development of 1 MJ Conduction-Cooled LTS Pulse Coil for UPS-SMES

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    A 1 MW, 1 s UPS-SMES is being developed for a protection from a momentary voltage drop and an instant power failure. As a key technology of the UPS-SMES, we developed a prototype LTS pulse coil with a stored energy of 100 kJ and conducted cooling and excitation tests in 2005. The operation test of the prototype UPS-SMES using this 100 kJ coil with power converters have been performed in 2006. A 1 MJ coil was designed before the fabrication of the 100 kJ prototype coil. The superconductor, the electric insulation technique, the winding method, and the cooling structure used for the 100 kJ coil were based upon the 1 MJ coil design. The successful performance test results of the prototype 100 kJ coil validated the design concept and fabrication technique of the 1 MJ coil. According to the achievement of the prototype 100 kJ UPS-SMES, the 1 MJ conduction-cooled LTS pulse coil has been fabricated successfully. The successful experimental results of the 100 kJ prototype coil with power converters and the fabrication procedure of the 1 MJ full size coil are described

    Ultrasonication-based rapid amplification of α-synuclein aggregates in cerebrospinal fluid

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    Kakuda K., Ikenaka K., Araki K., et al. Ultrasonication-based rapid amplification of α-synuclein aggregates in cerebrospinal fluid. Scientific Reports 9, 6001 (2019); https://doi.org/10.1038/s41598-019-42399-0.α-Synuclein aggregates, a key hallmark of the pathogenesis of Parkinson’s disease, can be amplified by using their seeding activity, and the evaluation of the seeding activity of cerebrospinal fluid (CSF) is reportedly useful for diagnosis. However, conventional shaking-based assays are time-consuming procedures, and the clinical significance of the diversity of seeding activity among patients remains to be clarified. Previously, we reported a high-throughput ultrasonication-induced amyloid fibrillation assay. Here, we adapted this assay to amplify and detect α-synuclein aggregates from CSF, and investigated the correlation between seeding activity and clinical indicators. We confirmed that this assay could detect α-synuclein aggregates prepared in vitro and also aggregates released from cultured cells. The seeding activity of CSF correlated with the levels of α-synuclein oligomers measured by an enzyme-linked immunosorbent assay. Moreover, the seeding activity of CSF from patients with Parkinson’s disease was higher than that of control patients. Notably, the lag time of patients with Parkinson’s disease was significantly correlated with the MIBG heart-to-mediastinum ratio. These findings showed that our ultrasonication-based assay can rapidly amplify misfolded α-synuclein and can evaluate the seeding activity of CSF

    Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon

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    A search for new isotopes using in-flight fission of a 345 MeV/nucleon 238U beam has been carried out at the RI Beam Factory at the RIKEN Nishina Center. Fission fragments were analyzed and identified by using the superconducting in-flight separator BigRIPS. We observed 45 new neutron-rich isotopes: 71Mn, 73,74Fe, 76Co, 79Ni, 81,82Cu, 84,85Zn, 87Ga, 90Ge, 95Se, 98Br, 101Kr, 103Rb, 106,107Sr, 108,109Y, 111,112Zr, 114,115Nb, 115,116,117Mo, 119,120Tc, 121,122,123,124Ru, 123,124,125,126Rh, 127,128Pd, 133Cd, 138Sn, 140Sb, 143Te, 145I, 148Xe, and 152Ba
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