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981.
In the improvement of a rotating tilted liquid column (RTC) method (closed and open-bottom column systems), we have developed a method for rapid selective separation of particulate materials in a continuous or semi-continuous process: a rotating tilted open column with steady flow (RSF) method. The separation power of the RSF method is represented as (aj/ai)n(RSF), where ai and aj are radii of particles with the same density. The power index n(RSF) will increase with increase of the column rotation ω within the practical range of 1.3 ? Aω/V0 ? 7, where A is the radius of the column and V0 is the free falling velocity of the particle.From the relationship between particle loci and distribution of liquid flow speed, we derive an approximate equation to calculate n(RSF) practically and demonstrate the relationship 2 < n(RTC) < n(RSF). Further, n(RSF) takes a maximum value at θ = 0° when ω is fixed, and it sometimes exceeds the upper limit (= 4) of n(RTC) in the RTC method.This method can be of use for the separation of fine particles, easily degenerated micro-organisms, etc. 相似文献
982.
Kato T Aoki K Yokoyama S Ejiri K Minami K Yashima H Taniguchi A Nakamura T Hirayama H 《Radiation protection dosimetry》2011,146(1-3):202-205
The conversion coefficients, H'(d,α)/Φ, for monoenergetic positrons and positron-emitting radionuclides were calculated by using the user code UCICRPM of the Monte Carlo code EGS5 to estimate the radiation dose for medical staff involved in positron emission tomography examinations. From these coefficients, the dose equivalent rates per unit activity at 0.07 and 10 mm depths in a soft tissue for a straight-line source of 2-deoxy-2-[(18)F]fluoro-d-glucose ((18)F-FDG) were calculated by using the developed user code UCF18DOSE. The dose equivalent rates per unit activity at 0.07 and 10 mm depths were measured by using a personal dosemeter (DOSE(3)) under the same conditions as those considered in the calculation. The calculated dose equivalent rates per unit activity at 0.07 and 10 mm depths were 0.116 and 0.0352 pSv min(-1) Bq(-1), respectively, at 20 cm from the (18)F-FDG injection tube. 相似文献
983.
Nakanishi H Walker DA Bishop KJ Wesson PJ Yan Y Soh S Swaminathan S Grzybowski BA 《Nature nanotechnology》2011,6(11):740-746
Switchable nanomaterials--materials that can change their properties and/or function in response to external stimuli-have potential applications in electronics, sensing and catalysis. Previous efforts to develop such materials have predominately used molecular switches that can modulate their properties by means of conformational changes. Here, we show that electrical conductance through films of gold nanoparticles coated with a monolayer of charged ligands can be controlled by dynamic, long-range gradients of both mobile counterions surrounding the nanoparticles and conduction electrons on the nanoparticle cores. The internal gradients and the electric fields they create are easily reconfigurable, and can be set up in such a way that electric currents through the nanoparticles can be modulated, blocked or even deflected so that they only pass through select regions of the material. The nanoion/counterion hybrids combine the properties of electronic conductors with those of ionic gels/polymers, are easy to process by solution-casting and, by controlling the internal gradients, can be reconfigured into different electronic elements (current rectifiers, switches and diodes). 相似文献
984.
Cinthio M Hasegawa H Kanai H 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(4):853-857
To detect minute roughness, we utilized the phase change that occurs in a radio frequency echo from the rough surface of an object during its lateral motion. The new method was optimized and validated using saw-tooth-shaped silicone phantoms sized from 13 to 33 μm; results were compared to those obtained using a confocal laser scanning microscope. 相似文献
985.
Nagaoka H Sato Y Xie X Hata H Eguchi M Sakurai N Watanabe T Saitoh H Kondo A Sugita S Ohnishi N 《Analytical chemistry》2011,83(24):9197-9200
Because current homogeneous immunoassays show some limitations, particularly low sensitivity, we developed a new immunoassay to overcome these limitations. The approach was based on magnetic nanoparticles with a thermoresponsive polymer layer, a negatively charged polymer, and streptavidin-biotin-based antibody-antigen detection and yielded higher sensitivity than commonly used heterogeneous immunoassays. Because no special equipment is needed, it can be applied to currently available absorbance-based systems for high-throughput assays. 相似文献
986.
In-solution enzymatic and nonenzymatic digestion methods have been successfully implemented in matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS)-based virus identification, extending to typing/subtyping of deadly influenza viruses. However, these methods are inefficient in obtaining more precise information on surface proteins of myxovirus particles, not only the hemagglutinin and neuraminidase of influenza virus but also the hemagglutinin-neuraminidase of Newcastle disease virus (NDV). Imbalances in viral protein composition cause ion suppression of tryptic fragments from low-abundant target proteins (surface proteins), adversely affecting reproducibility of mass spectra. Additionally, the coexistence of tryptic peptides from several proteins requires sophisticated statistical solutions for precise result interpretations. To circumvent these, we apply detergent-based (gel-free) partitioning of whole viruses into soluble surface proteins and insoluble virus materials, using differential centrifugation. MALDI-TOF or MALDI-TOF/TOF MS was applied to analyze tryptic peptides from separated viral proteins. In this study, we achieved type/subtype of avian influenza virus (AIV) within 5 h, based on 4 major proteins, by significantly reducing ion suppression and signal overlap from various protein sources. Hence, our approach can both yield dependable results and allow Web-based search engines to be directly employed, obviating the need for additional statistical strategy. Additionally, we demonstrate the utility of the method using NDV. 相似文献
987.
Hideyuki Okuma Kentaro Mori Suguru Nakamura Tetsuo Sekine Yoshihiro Ogawa Kyoichiro Tsuchiya 《International journal of molecular sciences》2021,22(14)
Sodium glucose cotransporter-2 (SGLT2) inhibitors inhibit the development of diabetic nephropathy (DN). We determined whether changes in perirenal fat (PRAT) by a SGLT2 inhibitor ipragliflozin (Ipra) contribute to the suppression of DN development. High-fat diet (HFD)-fed mice were used as a DN model and were treated with or without Ipra for 6 weeks. Ipra treatment reduced urinary albumin excretion (UAE) and glomerular hypertrophy in HFD-fed mice. In the PRAT of Ipra-treated mice, adipocyte size was increased, and inflammation, fibrosis, and adipocyte death were suppressed. In conditioned medium made from PRAT (PRAT-CM) of Ipra-treated mice, the concentration of leptin was significantly lower than PRAT-CM of mice without Ipra treatment. Serum leptin concentration in renal vein positively correlated with UAE. PRAT-CM from HFD-fed mice showed greater cell proliferation signaling in mouse glomerular endothelial cells (GECs) than PRAT-CM from standard diet-fed mice via p38MAPK and leptin-dependent pathways, whose effects were significantly attenuated in PRAT-CM from Ipra-treated mice. These findings suggest that Ipra-induced PRAT expansion may play an important role in the improvement of DN in HFD-fed mice. In vitro experiments suggest that reduced PRAT-derived leptin by Ipra could inhibit GECs proliferation, possibly contributing to the suppression of DN development. 相似文献
988.
Santosh Prasad Sah Yasuhiro Tatsuno Yoshitaka Aoki Hiroki Habazaki 《Corrosion Science》2011,53(5):1838-1844
Single pulse anodizing of aluminium micro-electrode has been employed to study the behaviour of dielectric breakdown and subsequent oxide formation on aluminium in alkaline silicate and pentaborate electrolytes. Current transients during applying pulse voltage have been measured, and surface has been observed by scanning electron microscopy. Two types of current transients are observed, depending on the electrolyte and applied voltage. There is a good correlation between the current transient behaviour and the shape of discharge channels. In alkaline silicate electrolyte, circular open pores are healed by increasing the pulse width, but such healing is not obvious in pentaborate electrolyte. 相似文献
989.
Kosuke O. Hara Eiji Yamasue Hideyuki Okumura Keiichi N. Ishihara 《Journal of Alloys and Compounds》2011
The phase transformation of α-MoSi2 into β-MoSi2 induced by mechanical milling (MM) was studied. Planetary ball milling was performed on an α-MoSi2 powder under six different milling conditions. The X-ray diffraction results show that the dynamic equilibrium between α-MoSi2 and β-MoSi2 is reached at low milling intensities, while a single phase of β-MoSi2 is formed when milled at high milling intensities. The single-phase β-MoSi2 formation is found to be due to Fe impurity. The mechanism of the phase transformation of MoSi2 is discussed, and the phase fractions under the dynamic equilibrium are explained by the redistribution of the close-packed layers via synchroshear processes. 相似文献
990.
Toan Thanh Dao Toshinori Matsushima Rainer Friedlein Hideyuki Murata 《Organic Electronics》2013,14(8):2007-2013
The authors report controllable threshold voltage (Vth) in a pentacene field-effect transistor based on a double-dielectric structure of poly(perfluoroalkenyl vinyl ether) (CYTOP) and SiO2. When a positive switching voltage is applied to the gate electrode of the transistor, electrons traverse through the pentacene and CYTOP layers and subsequently trapped at the CYTOP/SiO2 interface. The trapped electrons induce accumulation of additional holes in the pentacene conducting channel, resulting in a large Vth shift from ?4.4 to +4.6 V. By applying a negative switching voltage, the trapped electrons are removed from the CYTOP/SiO2 interface, resulting in Vth returning to an initial value. The Vth shift caused by this floating gate-like effect is reversible and very time-stable allowing the transistor to be applicable to a nonvolatile memory that has excellent retention stability of stored data. 相似文献