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121.
Yoshino K. Takeshita T. Kotaka I. Kondo S. Noguchi Y. Iga R. Wakita K. 《Lightwave Technology, Journal of》1999,17(9):1700-1707
Very compact electroabsorption optical modulator modules that demonstrate high coupling efficiency and high stability have been developed. The modules show very good potential such as an insertion loss as low as 5 dB, or ultrahigh speed modulation of up to 46 GHz. The module fabrication techniques are also applicable to other optical devices that require fiber connections at both facets 相似文献
122.
Iga Szpunar Sebastian Wachowski Tadeusz Miruszewski Kacper Dzierzgowski Karolina Górnicka Tomasz Klimczuk Magnus Helgerud Sørby María Balaguer José M. Serra Ragnar Strandbakke Maria Gazda Aleksandra Mielewczyk-Gryń 《Journal of the American Ceramic Society》2020,103(3):1809-1818
The cubic Ba0.5La0.5CoO3-δ was synthesized using solid state reaction. The structural properties were determined by the simultaneous refinement of Synchrotron Powder X-ray Diffraction and Neutron Powder Diffraction data. Iodometric titration was used to examine the oxygen stoichiometry and average cobalt oxidation state. Low-temperature magnetic studies show soft ferromagnetic character of fully oxidized material, with θP = 198(3) K and µeff = 2.11(2) µB. Electric measurements show the thermally activated nature of conductivity at low temperatures, whereas, due to the variable oxidation and spin state of cobalt, a single charge transport mechanism cannot be distinguished. Around room temperature, a wide transition from thermally activated conductivity to semi-metallic behavior is observed. Under the inert atmosphere, the oxygen content lowers and the cation ordering takes place, leading to coexistence of two, ordered and disordered, phases. As a result of this change, thermally activated conductivity is observed also at high temperatures in inert atmosphere. 相似文献
123.
Lactic acid bacteria have long been used in brewing to acidify mash or wort and in the production of traditional sour beer styles (Lambic, Gueuze) using spontaneous fermentation. This approach is time consuming (some sour beers are matured for three years to obtain the appropriate flavour), so many brewers choose a faster approach using mixed cultures (yeast and bacteria). In this study, the influence of the pitching sequence of bacteria and yeast on the fermentation process was evaluated (by rate of fermentation and acidification, attenuation degree and ethanol concentration). The trials were performed using three procedures: (i) the addition of bacteria followed by the yeast; (ii) the addition of the yeast followed by the bacteria and (iii) the simultaneous addition of yeast and bacteria. In each trial the following time intervals were applied: 24, 48 and 72 h. Weight loss of samples and drop in pH were measured daily, and ethanol content, real extract and lactic acid concentration measured at the end of the process. It was shown that the order of addition of yeast and bacteria determines the success of the lactic acid fermentation. The appropriate yield of lactic acid (ca. 6 g/L) and the drop in pH (<3.6) can be achieved by inoculating the bacteria prior to the inoculation of yeast. When yeast was pitched before the bacteria, the lactic acid content was ca. 2 g/L and pH was 3.9–4.2. © 2019 The Institute of Brewing & Distilling 相似文献
124.
Iwona Ben-Skowronek Joanna Sieniawska Emilia Pach Wiktoria Wrobel Anna Skowronek Zaklina Tomczyk Iga Rosolowska 《International journal of molecular sciences》2022,23(1)
The autoimmune reaction against the beta cells of the pancreatic islets in type 1 diabetes mellitus (T1DM) patients is active in prediabetes and during the development of the clinical manifestation of T1DM, but it decreases within a few years of the clinical manifestation of this disease. A key role in the pathogenesis of T1DM is played by regulatory T cell (Treg) deficiency or dysfunction. Immune interventions, such as potential therapeutic applications or the induction of the Treg-cell population in T1DM, will be important in the development of new types of treatment. The aim of this study was to evaluate innovative immune interventions as treatments for T1DM. After an evaluation of full-length papers from the PubMed database from 2010 to 2021, 20 trials were included for the final analysis. The analysis led to the following conclusions: Treg cells play an important role in the limitation of the development of T1DM, the activation or application of Tregs may be more effective in the early stages of T1DM development, and the therapeutic use of Treg cells in T1DM is promising but requires long-term observation in a large group of patients. 相似文献
125.
A systematic study of changing the reflectivity of a Si/SiO/sub 2/ mirror for 1.3- mu m GaInAsP/InP surface-emitting lasers is discussed. An effective threshold current of 4.5 mA at 77 K continuous operation has been obtained. This indicates a possibility of a submilliampere threshold at 77 K and approximately=20 mA at 300 K by optimizing the mirror reflectivity.<> 相似文献
126.
A 40-gb/s InGaAlAs-InAlAs MQW n-i-n Mach-Zehnder Modulator with a drive Voltage of 2.3 V 总被引:1,自引:0,他引:1
K. Tsuzuki T. Ishibashi T. Ito S. Oku Y. Shibata R. Iga Y. Kondo Y. Tohmori 《Photonics Technology Letters, IEEE》2005,17(1):46-48
We have developed a traveling-wave Mach-Zehnder modulator using an n-i-n heterostructure fabricated on an InP substrate. We obtained an extremely small /spl pi/ voltage (V/spl pi/) of 2.2 V, even for a short signal-electrode length of 3 mm. We confirmed that the device has an impedance-matched electrode and operates at 40 Gb/s with a single-ended drive voltage of 2.3 V. 相似文献
127.
Atsushi Iga 《Electrical Engineering in Japan》1993,113(6):17-34
This paper describes the water tree diagnoses of 6.6-kV class XLPE cables by the dc component method. The dc current component is measured by energizing the cable with ac high voltage, therefore, it would be suitable for on-line diagnoses. The dc component is considered to be caused by the rectifying effect of water trees inside the insulation. In laboratory tests, the dc component showed a good correlation with the degradation. However, almost no correlation was seen in the on-site measurement. The authors found that the cause of this bad correlation is the galvanic effect inside the jacket. This generates the noise current through the grounding circuit when the jacket resistivity is low. Based on this finding, the equivalent circuit of on-site measurement was proposed. Considering the equivalent circuit, this paper proposes nine methods for discriminating the dc component due to water tree from noise current. Also described are the analytical results of each method. Furthermore, the on-site or laboratory tests show that some of them are effective in separating the dc component due to water tree from noise current. 相似文献
128.
Hamamoto T. Furutani K. Kubo T. Kawasaki S. Iga H. Kono T. Konishi Y. Yoshihara T. 《Solid-State Circuits, IEEE Journal of》2004,39(1):194-206
This paper describes an all-digital delay-locked loop (DLL) architecture for over 667 Mb/s operating double-data-rate (DDR) type SDRAMs, which suppresses skews and jitters. Two novel replica adjusting techniques are introduced, in which timing skews caused by the clock input and data output circuits are reduced by a hierarchical phase comparing architecture and a replica check method with slow tester. Further, an improved phase interpolating method suppresses jitters caused by a boundary of the fine and coarse delays. A 512-Mb test device is fabricated using a 0.13-/spl mu/m DRAM process technology, in which skew and jitter suppressed 667-Mb/s (333-MHz) DDR operation has been verified. 相似文献
129.
Suzaki Y. Iga R. Kishi K. Kawaguchi Y. Matsumoto S. Okamoto M. Yamamoto M. 《Quantum Electronics, IEEE Journal of》1998,34(4):686-690
We have demonstrated an optical transceiver diode integrated with a spot-size converter. We clarify that the design of a detection layer is essential for the temperature- and polarization-insensitive characteristics of the responsivity. Because the detection layer was introduced, 0.65 dB of responsivity deviation was obtained in the wide temperature range of -10°C-85°C with a high laser performance. A spot-size converter enables the coupling loss to be 1.8 dB for a flat-end optical fiber. The frequency response was also obtained up to 1 GHz in both laser and detector modes 相似文献
130.
Sato H. Kashiwagi K. Niwano K. Iga T. Ikeda T. Mashiko K. Sumi T. Tsuchihashi K. 《Solid-State Circuits, IEEE Journal of》1996,31(12):1974-1980
A 1.9 GHz IF transceiver for the Japanese standard personal handy-phone system (PHS) is fabricated in a 0.8-μm BiCMOS process with 20 GHz npn. A down-mixer, up-mixer, variable attenuator, quadrature modulator, first and second PLL, and second VCO are included in the 3.4×3.0 mm2 chip. The chip draws 24 mA in receive mode and 44 mA in transmit mode, operating from 3.0 V. A total vector error of 4% for the π/4 QPSK PN9 pattern includes the up-mixer and the dual PLLs 相似文献