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641.
E. A. Aramaki P. Porto L. Berni R. Y. Honda M. Ueda I. Doi M. Machida 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1989,280(2-3):597-601
The best operation condition on the field-reversed theta-pinch TC-I at UNICAMP is studied by analysis of the helium-plasma light emission and electromagnetic signals observed during the preionization and implosion phase of FRC plasma. The TC-I device can be operated with a crowbar switch on the preionization and main capacitor banks, in order to fix the number of oscillations as well as the time interval between the end of the preionization and the main discharge phase. A detailed study of the plasma implosion has been carried out by changing the above parameters and also the working gas pressure by using a photodiode, a visible spectrometer, magnetic probes, a Faraday cup and a streak camera. 相似文献
642.
Akitoshi Hotta Miyuki Akiba Yuki Doi Akinobu Morita 《Journal of Nuclear Science and Technology》2019,56(1):55-69
ABSTRACTA framework of the modular code system, THERMOS, aiming to evaluate cooling of a debris bed having complex configurations was introduced with a focus on one of the major modules, DPCOOL, which models heating or non-heating porous media of particulate debris in a two-phase pool. In DPCOOL, pool and debris bed regions are discretized in a three-dimensional Cartesian coordinate system. A pool region is formulated based on the two-fluid model. A two-phase flow in the debris bed region is formulated based on the Tung & Dhir model with modifications for smaller particles proposed by Schmidt. In order to synthesize the momentum equations of the two regions, interpolation factors as piecewise linear functions of porosity are introduced. The interfacial friction model was validated based on Chu’s test using a debris bed composed of non-heating SUS spheres in a water pool with air injection from below where the net water flow in the layer became zero so that pressure loss of the layer was governed by interfacial friction. The sum of the two-phase flow friction and the interfacial friction models was validated based on top flooding and bottom flooding tests conducted in IKE’s DEBRIS test facility loaded with mixed steel and alumina spheres that were heated by an induction coil system. 相似文献
643.
Structure ignition by wind-driven firebrand showers is an important fire spread mechanism in large outdoor fires. Experiments were conducted with three common mulch types (shredded hardwood mulch, Japanese Cypress wood chips, and pine bark nuggets) placed adjacent to realistic-scale re-entrant corners. In the first series of experiments, mulch beds were placed adjacent to a re-entrant corner constructed with wood studs and lined with oriented strand board (OSB) as the sheathing. The premise behind conducting experiments with no siding treatments applied was predicated on the notion that bare OSB mulch contact would be a worst-case scenario, and therefore, a wall assembly in the most vulnerable state to mulch ignition. In the second series of experiments, vinyl siding was applied to the re-entrant corner assemblies (wood studs/OSB/moisture barrier/vinyl siding), and the influence of vertical separation distance (102 mm or 203 mm) on wall ignition from adjacent mulch beds was determined. The vertical separation distance was maintained by applying gypsum board to the base of the re-entrant corner. The siding itself did not influence the ignition process for the mulch beds, as the mulch beds were the first to ignite from the firebrand showers. In all experiments, it was observed that firebrands produced smoldering ignition in the mulch beds, this transitioned to flaming ignition, and the re-entrant corner assembly was exposed to the flaming mulch beds. With no siding treatments applied, the flaming mulch beds ignited the re-entrant corner, and ignition was observed to propagate to the back side of re-entrant corner assembly under all wind speeds (6 m/s to 8 m/s). With respect to the re-entrant corners fitted with vinyl siding, the mulch type, vertical separation distance, and wind speed were important parameters as to whether flaming ignition was observed to propagate to the back-side of a re-entrant corner assembly. Mulches clearly pose an ignition hazard to structures in large outdoor fires. 相似文献
644.
Dr. Shuhei Takatani Dr. Tsuyoshi Tahara Dr. Mieko Tsuji Daiki Ozaki Nina Shibata Dr. Yoshinobu Hashizume Prof. Masaaki Suzuki Prof. Hirotaka Onoe Prof. Yasuyoshi Watanabe Dr. Hisashi Doi 《ChemMedChem》2021,16(21):3271-3279
The efficient synthesis of L-[5-11C]leucine and L-α-[5-11C]methylleucine has been investigated using a continuous two-step sequence of rapid reactions consisting of Pd0-mediated 11C-methylation and microfluidic hydrogenation. The synthesis of L-[5-11C]leucine and L-α-[5-11C]methylleucine was accomplished within 40 min with a decay-corrected radiochemical yield of 15–38 % based on [11C]CH3I, radiochemical purity of 95–99 %, and chemical purity of 95–99 %. The Pd impurities in the injectable solution measured using inductively coupled plasma mass spectrometry met the international criteria for human use. Positron emission tomography scanning after an intravenous injection of L-[5-11C]leucine or L-α-[5-11C]methyl leucine in A431 tumor-bearing mice was performed. As a result, L-α-[5-11C]methylleucine was found to be a potentially useful probe for visualizing the tumor. Tissue distribution analysis showed that the accumulation value of L-α-[5-11C]methylleucine in tumor tissue was high [12±3% injected dose/g tissue (%ID/g)]. 相似文献
645.
Fanlong Meng Jeff Z. Y. Chen Masao Doi Zhongcan Ouyang 《American Institute of Chemical Engineers》2014,60(4):1393-1399
When a cylindrical balloon is inflated, inflation often takes place nonuniformly, inflated near one end first and followed by the growth of this part along the entire cylinder. This phenomenon is discussed from the phase‐transition perspective in terms of the Gent model, a free‐energy model that has the same structure as that of the gas–liquid transition in normal fluids. A phase diagram which describes the inflation behavior is constructed, showing the binodal and spinodal curves terminated at a critical point. The hysteresis effects are discussed based on the phase diagram. The interface between the coexisting inflated and weakly inflated regions along the cylindrical balloon is also examined, and the interfacial thickness and the interfacial energy are numerically calculated. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1393–1399, 2014 相似文献
646.
Sayaka Shimizu Yuri Yamauchi Atsushi Ishikawa 《International journal of molecular sciences》2021,22(9)
In plant–pathogen interactions, a proper light environment affects the establishment of defense responses in plants. In our previous experiments, we found that nonhost resistance (NHR) to Pyricularia oryzae Cav. in Arabidopsis thaliana (L.) Heynh. (Arabidopsis), in diurnal conditions, varies with the inoculation time. Moreover, we indicated that the circadian clock plays an important role in regulating time-of-day differences in NHR to P. oryzae in Arabidopsis. However, the involvement of photoperiod in regulating NHR was still not understood. To determine the photoperiod role, we performed the experiments in continuous light and darkness during the early Arabidopsis–P. oryzae interaction. We found that the light period after the inoculation in the evening enhanced the resistance to penetration. However, the dark period after the inoculation in the morning suppressed the penetration resistance. Furthermore, the genetic analysis indicated that jasmonic acid, reactive oxygen species, and tryptophan-derived metabolite(s) contribute to the photoperiod regulation of NHR in Arabidopsis. The present results denote that photoperiod plays an important role in regulating time-of-day differences in NHR to P. oryzae in Arabidopsis. 相似文献
647.
Oda Naoki Kurashina Seiji Miyoshi Masaru Doi Kohei Ishi Tsutomu Sudou Takayuki Morimoto Takao Goto Hideki Sasaki Tokuhito 《Journal of Infrared, Millimeter and Terahertz Waves》2015,36(10):947-960
Journal of Infrared, Millimeter, and Terahertz Waves - A pixel in an uncooled microbolometer terahertz (THz) focal plane array (FPA) has a suspended structure above read-out integrated circuit... 相似文献
648.
Although anycast communication supports service-oriented addresses, many of its current definitions in IPv6 are unclear. Furthermore, since there are no protocol standards or even a consensus on controlling routing, intersegment anycast communications are not yet available. In this article we first review IPv6-based anycast communication. At present, there are several possible applications that are suited to this. We then raise several problems and provide possible solutions to these. Based on this background, we present the Anycast Address Resolving Protocol (AARP) to establish TCP connections with a specific anycast address, and then propose a routing protocol for intersegment anycasts. Our proposed architecture makes anycast addresses.more useful without (or with at most minimal) need for modifications/extensions to existing applications and/or upper-layer protocols. 相似文献
649.
Toshiyuki Kawai Mitsuru Takemoto Shunsuke Fujibayashi Haruhiko Akiyama Seiji Yamaguchi Deepak K. Pattanayak Kenji Doi Tomiharu Matsushita Takashi Nakamura Tadashi Kokubo Shuichi Matsuda 《Journal of materials science. Materials in medicine》2013,24(7):1707-1715
Bone ingrowth into porous Ti metal is important for stable fixation of Ti metal implants to surrounding bone. However, without surface treatment this is limited to only a thin region of the outer surface of the Ti metal. In the present study, a porous Ti metal with a porosity of ~60 % and interpore connections of 70–200 micrometers in diameter was investigated in terms of its chemical and heat treatments, by implanting it into rabbit femur for periods varying from 3 to 12 weeks. The porous Ti metal subjected to heat treatment at 600 °C after H2SO4/HCl mixed acid treatment showed the largest bone ingrowth in comparison with those subjected to no treatment, only acid treatment, and only heat treatment even at an early stage after implantation, and remained as such even 12 weeks after implantation. Their bone ingrowths were well interpreted in terms of apatite-forming abilities of the Ti metals in body environment. Their apatite-forming abilities did not depend upon their surface roughness nor type of crystalline phase, but upon the positive surface charge. 相似文献
650.
Use of the anion gap and intermittent hemodialysis following continuous hemodiafiltration in extremely high dose acute‐on‐chronic lithium poisoning: A case report 下载免费PDF全文
Yohei Komaru Ryota Inokuchi Yoshihiro Ueda Masaomi Nangaku Kent Doi 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(1):E15-E18
A 35‐year‐old woman intentionally took 40,000 mg of lithium carbonate, and she was transferred to our hospital with nausea, vomiting, and diarrhea. She was diagnosed as having bipolar disorder 10 years ago and was receiving oral lithium therapy. Blood test results on arrival were remarkable for a negative anion gap of ?2.1 and later, the serum lithium level turned out to be as high as 15.4 mEq/L. Intubation was required because of disrupted consciousness, and continuous hemodiafiltration (CHDF) was immediately started in the intensive care unit to obtain constant removal of lithium. After adding intermittent hemodialysis (IHD) twice during the daytime to accelerate the lithium clearance, CHDF became unnecessary on day 4, and she was extubated on day 6 with complete recovery of consciousness. Close monitoring of the patient data showed recovery of the decreased anion gap as indicator of the serum lithium level reduction. On day 36, she was discharged without any complication and sequela. The current case highlighted the effective use of CHDF between IHD sessions to prevent the rebound elevation of lithium and the role of the anion gap as a surrogate marker of serum lithium concentration during the treatment. 相似文献