281 research outputs found

    Concurrent Determination of Magnesium and Calcium in Iron Ores by Atomic Absorption Spectroscopy

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    Examinations were made for the concurrent determination of magnesium and calcium in iron ores when present in about equal amounts, using the magnesium-calcium coupled type hollow-cathode lamp in atomic absorption spectroscopy, and a method of measurement was established. Concurrent determination was found to be easily possible by removal of the majority of iron by extraction with methyl isobutyl ketone and addition of strontium. Analytical precision was calculated and found to give satisfactory results (standard deviations : ±0.004% for Ca, ±0.006% for Mg)

    Method for Identifying Type of Eddy-Current Displacement Sensor

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    Eddy-current (EC) displacement sensors are used in a device for measuring the shaft vibration of turbines. An EC displacement sensor is composed of a sensor probe and an impedance/output voltage (Z/V) converter. In a power plant in the U. S., the type of the sensor probe and the displacement from the turbine shaft to the tip of the sensor probe (displacement x) are not controlled. For this reason, when only the Z/V converter breaks down, the plant is stopped and dismantled, and both the Z/V converter and the sensor probe are replaced. This results in two problems, i.e., the unstable supply of electric power when the power plant is stopped and the high cost of dismantling the plant. If both the type of the sensor probe and x are identified during turbine operation, the aforementioned problems could be solved. In this paper, we describe that the three types of the sensor probe and x can be identified by comparing the measured the maximum quality factor Q(EC) (max) and frequency f(o) at Q(EC) (max) with the Q(EC) (max) versus f(o) characteristics of sensor probes.ArticleIEEE TRANSACTIONS ON MAGNETICS. 47(10):3554-3557 (2011)journal articl

    An Al-doped SrTiO3 photocatalyst maintaining sunlight-driven overall water splitting activity for over 1000 h of constant illumination

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    Photocatalytic water splitting is a viable approach to the large-scale production of renewable solar hydrogen. The apparent quantum yield for this reaction has been improved, but the lifespan of photocatalysts functioning under sunlight at ambient pressure have rarely been examined, despite the critical importance of this factor in practical applications. Herein, we show that Al-doped SrTiO3 (SrTiO3: Al) loaded with a RhCrOx (rhodium chromium oxide) cocatalyst splits water with an apparent quantum yield greater than 50% at 365 nm. Moreover, following the photodeposition of CoOOH and TiO2, this material maintains 80% of its initial activity and a solar-to-hydrogen energy conversion efficiency greater than or equal to 0.3% over a span of 1300 h under constant illumination by simulated sunlight at ambient pressure. This result is attributed to reduced dissolution of Cr in the cocatalyst following the oxidative photodeposition of CoOOH. The photodeposition of TiO2 further improves the durability of this photocatalyst. This work demonstrates a concept that could allow the design of longterm, large-scale photocatalyst systems for practical sunlight-driven water splitting.ArticleCHEMICAL SCIENCE.10(11):3196-3201(2019)journal articl

    Quantitative Analysis of Macular Inner Retinal Layer Using Swept-Source Optical Coherence Tomography in Patients with Optic Tract Syndrome

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    Objective. To evaluate macular inner retinal layers using swept-source optical coherence tomography (SS-OCT) in patients with homonymous hemianopia due to optic tract syndrome (OTS). Methods. Sixteen eyes of 8 patients with OTS were studied. The macular retinal nerve fiber layer (mRNFL), ganglion cell layer and inner plexiform layer (GCL + IPL), and mRNFL and GCL + IPL (GCC) were measured by SS-OCT (DRI OCT-1 Atlantis®).The scanned area was divided into eight regions and two hemiretinae. Each retinal thickness of the OTS group was compared with that of the 25 control subjects. Results. The GCC thickness in the ipsilateral eyes was significantly reduced in all regions, although predominant thinning of the GCC in the contralateral eyes was found in the nasal region. The GCC + IPL thickness was preferentially reduced at the temporal regions in the ipsilateral eyes and at the nasal regions in the contralateral eyes. The reduction rate of the GCL + IPL thickness was 29.6% at the temporal hemiretina in the ipsilateral eyes and 35.2% at the nasal hemiretina in the contralateral eyes. Conclusion. We found preferential loss of the GCC + IPL thickness corresponding to the hemifield defects in each eye. Quantitative analysis by SS-OCT is capable of detecting the characteristic RGC loss due to OTS

    Testing the Nambu-Goldstone Hypothesis for Quarks and Leptons at the LHC

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    The hierarchy of the Yukawa couplings is an outstanding problem of the standard model. We present a class of models in which the first and second generation fermions are SUSY partners of pseudo-Nambu-Goldstone bosons that parameterize a non-compact Kahler manifold, explaining the small values of these fermion masses relative to those of the third generation. We also provide an example of such a model. We find that various regions of the parameter space in this scenario can give the correct dark matter abundance, and that nearly all of these regions evade other phenomenological constraints. We show that for gluino mass ~700 GeV, model points from these regions can be easily distinguished from other mSUGRA points at the LHC with only 7 fb^(-1) of integrated luminosity at 14 TeV. The most striking signatures are a dearth of b- and tau-jets, a great number of multi-lepton events, and either an "inverted" slepton mass hierarchy, narrowed slepton mass hierarchy, or characteristic small-mu spectrum.Comment: Corresponds to published versio
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