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排序方式: 共有1021条查询结果,搜索用时 31 毫秒
61.
Toshihiro Tsuchiyama Kyoka Tsugumi Tianze Ma Takuro Masumura Yoshinori Ono 《国际钢铁研究》2023,94(10):2200428
62.
H Kagawa Y Komiyama S Nakamura T Miyake Y Miyazaki K Hamamoto M Masuda H Takahashi S Nomura S Fukuhara 《Canadian Metallurgical Quarterly》1998,91(6):297-304
An autopsy case of Sj?gren-Larsson syndrome (SLS), an 8-year-old boy, is presented with neuropathological investigations. Widespread deposition of 2 different types of unusual substances, stained lightly or strongly with periodic acid Schiff (PAS) was most conspicuous in this case. The first type of them, lightly stained with PAS at room temperature, was widely distributed in the central nervous system (CNS): the white matter of cerebrum and brainstem, subpial and subependymal glial layers, subpial space, perivascular space of small blood vessels, and their adjacent nervous tissue. The second type, strongly stained with PAS, small round or ellipsoid bodies, was found in the subpial, subependymal and perivascular glial layers. The first type of PAS-positive substances might be fatty alcohols or their metabolites, and the second type, some degraded products of lipids in astrocytic processes. Lipofuscin-like substances were accumulated in perivascular macrophages located around small blood vessels. Spheroid bodies (axonal swellings) were frequently observed in relay nuclei: lateral geniculate body (LGB), pontine nuclei, inferior olivary nuclei, posterior funicular nuclei, or cerebellar dentate nuclei. A lot of PAS-positive fine granules were contained in a spheroid body of LGB. Scarcity of myelinated nerve fibers was recognized in the cerebral and cerebellar white matter and the corticospinal tracts of spinal cord. Focal cortical dysgenesis, resembling that of unlayered polymicrogyria, was observed in bilateral insular cortices. Further histochemical studies are needed to explore the exact pathogenesis, but widespread deposition of PAS-positive substances in CNS may support the supposition that SLS is one of congenital errors of lipid metabolism. 相似文献
63.
Khutoryan Eduard Kuleshov Alexei Ponomarenko Sergey Lukin Konstantin Tatematsu Yoshinori Tani Masahiko 《Journal of Infrared, Millimeter and Terahertz Waves》2021,42(6):671-683
Journal of Infrared, Millimeter, and Terahertz Waves - Various regimes of hybrid, bulk-surface, modes being excited in the clinotron oscillator with a sheet electron beam and nonuniform grating... 相似文献
64.
65.
Keisuke Ueda Yoh Matsuki Toshimichi Fujiwara Yoshinori Tatematsu Isamu Ogawa Toshitaka Idehara 《Journal of Infrared, Millimeter and Terahertz Waves》2016,37(9):825-836
A 394-GHz gyrotron, FU CW GII, has been designed at the University of Fukui, Japan, for dynamic nuclear polarization (DNP)-enhanced solid-state nuclear magnetic resonance (SSNMR) experiments at 600-MHz 1H resonant frequency. After installation at the Institute for Protein Research (IPR), Osaka University, Japan, a PID feedback control system was equipped to regulate the electron gun heater current for stabilization of the electron beam current, which ultimately achieved stabilization of output power when operating in continuous wave (CW) mode. During exploration to further optimize operating conditions, a continuous tuning bandwidth of approximately 1 GHz was observed by varying the operating voltage at a fixed magnetic field. In the frequency range required for positive DNP enhancement, the output power was improved by increasing the magnetic field and the operating voltage from their initial operational settings. In addition, fine tuning of output frequency by varying the cavity cooling water temperature was demonstrated. These operating conditions and ancillary enhancements are expected to contribute to further enhancement of SSNMR signal. 相似文献
66.
The cell leakage of a stacked trench capacitor (STT) cell has been investigated. The major leakage mechanisms of the STT are trench-to-trench leakage, trench junction leakage, and LOCOS isolation leakage. It is shown that compared to a conventional trench capacitor, the trench-to-trench leakage current is reduced and high punchthrough voltage is obtained. Therefore, the trench-to-trench spacing can be reduced 0.1 μm shorter than that of the trench capacitor. These reductions result from the STT structure itself. The surface leakage current, which is the dominant leakage current in the trench capacitor, does not flow in the STT. This paper also describes the effect of the sidewall damage caused by trench etching on the trench junction leakage. Reactive ion etching (RIE) produces deep levels just beneath the trench surface. But, the trench junction of the STT is not influenced by these deep levels because the trench surface is covered by a n-diffused layer. This paper also investigates the relationship between the cell leakage and the retention time. At DRAM operation temperatures, LOCOS isolation leakage is dominant rather than trench junction leakage. Therefore, the deeper trench can increase the storage capacitance and improve the retention time 相似文献
67.
Akira Akahira K. C. A. Alam Yoshinori Hamamoto Atsushi Akisawa Takao Kashiwagi 《International Journal of Refrigeration》2004,27(3):530
The study investigates the performance of two-bed, silica gel-water adsorption refrigeration cycle with mass recovery process. The cycle with mass recovery can be driven by the relatively low temperature heat source. In an adsorption refrigeration cycle, the pressures in adsorber and desorber are different. The chiller with mass recovery process utilizes the pressure difference to enhance the refrigerant mass circulation. Cooling capacity and coefficient of performance (COP) were calculated by cycle simulation computer program to analyze the influences of operating conditions. The mass recovery cycle was compared with conventional cycle such as the single stage adsorption cycle in terms of cooling capacity and COP. The results show that the cooling capacity of mass recovery cycle is superior to that of conventional cycle and the mass recovery process is more effective for low regenerating temperature. 相似文献
68.
Qiang Dong Nobuhiro Kumada Yoshinori Yonesaki Takahiro Takei Nobukazu Kinomura Dan Wang 《Journal of Materials Science》2010,45(20):5685-5691
Hollow hematite (α-Fe2O3) microspheres with an average diameter of 3-4 μm and a shell thickness of approximate 150 nm was synthesized by a simple hydrothermal route using FeCl3·6H2O solution and acetic acid without using any templates. The hollow microspheres were composed of α-Fe2O3 nanoparticles with the diameter range from 20 to 40 nm. The effects of reaction parameters such as reaction time, temperature, concentration of FeCl3·6H2O solution, and initial pH on the morphology of the final products were investigated. A possible formation mechanism of hollow α-Fe2O3 microspheres was also proposed, where the acetic acid played a role of etching in the formation of hollow structure. 相似文献
69.
T. Takeuchi T. Sasaki M. Hayashi K. Hamamoto K. Makita K. Taguchi K. Komatsu 《Photonics Technology Letters, IEEE》1996,8(3):361-363
A transceiver PIC consisting of a DFB-LD, a receiver PD and a Y-shaped branch waveguides is realized by in-plane bandgap energy controlled selective MOVPE. Both active and passive core layers are formed in one step selective growth, and complicated fabrication procedure is no longer required. More than 1 mW fiber coupled power and 7 GHz receiver bandwidth are obtained. The modulation and detection operations at 500 Mb/s are successfully demonstrated. 相似文献
70.
Praneeth Wickramarachchi Kaushalya Ranasinghe Shoichiro Hamamoto Ken Kawamoto Udeni P. Nawagamuwa Per Moldrup Toshiko Komatsu 《Canadian Metallurgical Quarterly》2011,15(4):285-295
Gas exchange through the compacted final cover soil at landfill sites plays a vital role for emission, fate, and transport of toxic landfill gases. This study involved measuring the soil-gas diffusivity (Dp/Do, the ratio of gas diffusion coefficients in soil and free air) and air permeability (ka) for differently compacted soil samples (reddish-brown soil) from the final cover at the Maharagama landfill in Sri Lanka. The samples were prepared by either standard Proctor compaction or hand compaction to dry bulk densities of 1.60–1.94??g?cm-3. Existing and modified models for predicting Dp/Do and ka were tested against the measured data. The simple, single-parameter Buckingham model predicted measured Dp/Do values across compaction levels equally well or better than a dry bulk density (DBD) dependent model and a soil-water retention (SWR) dependent model. The measured ka values for differently compacted samples were highly affected by the compaction level and the sample moisture preparation method. Also, for air permeability, a single-parameter Buckingham-type ka model was most accurate in predicting ka in the differently compacted soil samples. Equivalent air-filled pore diameters (the effective diameter of the drained pores active in leading air through the sample) for gas flow, deq, were calculated from the measured Dp/D0 and ka values. The deq increased with compaction level, suggesting that a very high compaction level creates well-connected macropores in the reduced total pore space of the cover soil. This is an important consideration when designing cover soils for optimally low water and high oxygen exchange while minimizing climate and toxic gas emissions from the waste layer to the atmosphere. 相似文献