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51.
This paper presents a novel built-in current sensor that uses two additional power supply voltages besides the system power supply voltage, and that is constructed by using a current mirror circuit to pick up an abnormal IDDQ. It is activated only by an abnormal quiescent power supply current and minimizes the voltage drop at the terminal of the circuit under test. Simulation results showed that it could detect 16-A IDDQ against 0.03-V voltage drop at 3.3-V VDD and that it reduced performance degradation in the circuit under test. It is therefore suitable for testing low-voltage integrated circuits. Moreover, we verified the behavior of the sensor circuit implemented on the board by using discrete devices. Experimental results showed that the real circuit of the sensor functioned properly. 相似文献
52.
Riku Kawasaki Kosuke Kondo Risako Miura Keita Yamana Hinata Isozaki Risako Shimada Shogo Kawamura Hidetoshi Hirano Tomoki Nishimura Naoki Tarutani Kiyofumi Katagiri Alexandra Stubelius Shin-ichi Sawada Yoshihiro Sasaki Kazunari Akiyoshi Atsushi Ikeda 《International journal of molecular sciences》2022,23(9)
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy. 相似文献
53.
Raimundo Almeida-Filho Fernando P. Miranda Tadashi Yamakawa 《International journal of remote sensing》2013,34(13):2683-2688
Mapping of a tonal anomaly in an area of hydrocarbon microseepage was possible using a Landsat-Thematic Mapper false-colour composite consisting of TM2/3, TM4/3 and of the difference TM2/3-TM4/3, displayed as red, green and blue, respectively. In this false-colour composite, green and yellow express variations in the vegetation cover, whereas hues of magenta are related to terrain conditions representing bleached materials, which occur close to the centre of a soil gas anomaly. Simultaneous occurrence of anomalous soil gas values with magnetic and radioactive minerals suggests that a reducing environment associated with the microseepage phenomenon created the bleached materials, identified as a tonal anomaly in the enhanced TM image. 相似文献
54.
Li-Ngee Ho Hiroshi Nishikawa Tadashi Takemoto 《Journal of Materials Science: Materials in Electronics》2011,22(5):538-544
The effects of different copper fillers with different morphology and particle size have been studied in terms of electrical resistivity and thermal stability on the electrically conductive adhesives. The copper fillers used in this study were prepared by wet chemical reduction, electrolytic and gas atomization method, respectively. The as cured ECAs filled with different type of Cu fillers showed significant difference in electrical resistivity. Cu filler with smaller particle size showed higher packing density and larger surface area, which would enhance formation of conductive channels and increased conductive network in the ECAs, leading to a lower electrical resistivity. In addition, thermal stability of the ECAs were investigated under high temperature exposure at 125 °C and high humidity aging at 85 °C/85% RH for 1,000 h. Results showed that ECAs with Cu fillers of relatively small particle size and rough particle surface have excellent thermal stability due to enhanced adhesion and contact area between Cu fillers and the polymer matrix. A very low resistivity at an order of magnitude of 10?4 ?? cm could be maintained for these ECAs after 1,000 h at 125 and 85 °C/85% RH. 相似文献
55.
Stabilization of a Power System Including Inverter‐Type Distributed Generators by a Virtual Synchronous Generator 下载免费PDF全文
The capacity of distributed generators (DGs) connected to the grid by inverters is growing year after year. The inverters are generally controlled by a phase locked loop (PLL) in order to achieve synchronization with the power system frequency. Power systems may become unstable as the capacity of the inverter‐type DGs continues to increase, because the inverter frequency is controlled just to follow the frequency determined by other synchronous generators. It has been suggested that inverters be controlled to behave like a synchronous generator. This concept is referred to as the virtual synchronous generator (VSG). In this paper, a control scheme for a VSG is presented, and the design method for the required energy storage and the capacity for grid stabilization control by a VSG is investigated by computer simulations. 相似文献
56.
The mere exposure effect refers to the phenomenon where previous exposures to stimuli increase participants’ subsequent affective preference for those stimuli. This study explored the effect of selective attention on the mere exposure effect. The experiments manipulated the to-be-attended drawings in the exposure period (either red or green polygons in Experiments 1 and 2; both red and green polygons in Experiments 3 and 4) and black to-be-evaluated drawings in the affective judgment period (morphologically identical to the red or green polygons in Experiments 1 and 4; morphologically identical to the composite drawings in Experiments 2 and 3). The results showed a significant mere exposure effect only for the target shapes involved in attentional selection, even when the participants could recognize the nontarget shapes. This indicates that selective attention modulated the mere exposure effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Fumio Yoshii Keizo Makuuchi Shingo Kikukawa Tadashi Tanaka Jun Saitoh Kiyohito Koyama 《应用聚合物科学杂志》1996,60(4):617-623
High-melt-strength polypropylene (PP) was achieved with irradiation by an electron beam generated from an accelerator in the presence of polyfunctional monomers (PFM). Among 16 PFMs, the relatively shorter molecular chain bifunctional monomers such as 1,4-butanediol diacrylate (BDDA) and 1,6-hexanediol diacrylate (HDDA) were the most effective for enhancing the melt strength of PP. The concentration and dose of the HDDA to obtain the high melt strength PP in irradiation under nitrogen gas atmosphere were 1.5 mmol/100 g PP and 1 kGy, respectively. DSC measurement and dynamic mechanical analysis showed that the thermal behavior of the high-melt-strength PP was different from that of the original PP. Crystallinity and crystallization temperature during cooling after heating were lower and higher in high melt strength PP than original PP, respectively. Elongational viscosity at 180°C of the high-melt-strength PP showed a remarkable increase at a certain elongational time with constant strain rate, demonstrating the typical property of high-melt-strength samples. This implies that a few higher molecular chains of PP, formed by intermolecular combination of its chain by HDDA in irradiation, give higher melt strength to induce entanglement of molecular chains. © 1996 John Wiley & Sons, Inc. 相似文献
58.
Kawase M Kurikawa N Higashiyama S Miura N Shiomi T Ozawa C Mizoguchi T Yagi K 《Journal of Bioscience and Bioengineering》1999,88(4):433-437
Cationic polyamidoamine dendrimers are known to be highly branched cascade polymers. Tripeptide growth factor, glycyl-L-histidyl-L-lysine (GHK), was employed as a ligand for activation or attachment of cells from a rat hepatoma cell line, H4-H-E-C3, and immobilized at the terminus of the dendrimer (GHK-dendrimer) to develop a suitable surface for use as a culture substratum in the bioartificial liver support system (BAL). The growth of cells was inhibited by increasing the number of generations of GHK-dendrimers. On the other hand, urea synthesis and lidocaine clearance of the cells adhered on fifth generation GHK-dendrimers were enhanced much more than on first generation GHK-dendrimers. GHK was shown to act as a growth inhibitor and an activator of hepatoma cells. These properties of GHK are advantageous for the utilization of hepatoma cells in BAL. Ligand-modified dendrimers are very promising for the creation of a high-performance substratum for cell culture and high performance bioartificial organs, as well as for high-performance bioartificial liver systems. GHK may have the potential to be a highly useful ligand. 相似文献
59.
Contrasting effects of water-soluble and water-insoluble dietary fibers on bile acid conjugation and taurine metabolism in the rat 总被引:2,自引:0,他引:2
The effect of the type of dietary fiber on the bile acid and taurine metabolism was examined in rats. Diets containing 10%
of various water-soluble fibers (citrus pectin, konjak mannan, guar gum) as compared to a fiber-free diet increased biliary
excretion of total bile acids. In contrast, water-insoluble dietary fibers (cellulose, corn bran, chitin; 10% in the diets)
as well as cholestyramine (5% in the diet) considerably, decreased bile acid excretion. Water-soluble dietary fibermediated
increases in bile acid excretion were totally attributable to increases in glycine-conjugates. Thus, these fibers greatly
increased by the bile acid glycine-to-taurine ratio (G/T). Excretio of glycine conjugates decreased more than that of taurine
conjugates in rats fed various water-insoluble dietary fibers. As a results, G/T in rats fed water-insoluble fibers was significantly
lowered as compared to G/T in animals fed a fiber-free diet. Cholestyramine did not affect the G/T ratio of bile acids. Fecal
bile acid excretion and the activities of hepatic cholesterol 7α-hydroxylase (EC 1.14.13.17) in rats fed various water-soluble
dietary fibers approximately doubled as compared to the respective values for rats fed a fiber-free diet. Whereas cholestyramine
greatly increased these parameters, water-insoluble fibers did not significantly affect them. Various water-soluble fibers
decreased hepatic concentration and urinary excretion of taurine as well as the activity of hepatic cysteine dioxygenase (EC
1.13.11.20). In contrast, water-insoluble fibers considerably increased hepatic taurine concentrations and enzyme activities.
The parameters for taurine metabolism were unaffected by cholestyramine. It was suggested that the types of dietary fiber
affected hepatic taurine synthesis and thus modified bile acid glycine/taurine ratios. 相似文献
60.
The thermal performance of a chemical heat pump that uses the reaction system of calcium oxide/lead oxide/carbon dioxide, which is developed for utilization of high‐temperature heat above 800°C, is studied experimentally. The thermal performance of a packed‐bed reactor of a calcium oxide/carbon dioxide reaction system, which stores and transforms a high‐temperature heat source in the heat pump operation, is examined under various heat pump operation conditions. The energy analysis based on the experiment shows that it is possible to utilize high‐temperature heat with this heat pump. This heat pump can store heat above 850°C and then transform it into a heat above 900°C under an approximate atmospheric pressure. An applied system that combines the heat pump and a high‐temperature process is proposed for high‐efficiency heat utilization. The scale of the heat pump in the combined system is estimated from the experimental results. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献