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141.
Toshiki Tsubota Kaori TakenakaNaoya Murakami Teruhisa Ohno 《Journal of power sources》2011,196(23):10455-10460
In order to investigate the performance of an electrochemical capacitor consisting of a nitrogen- and sulfur-containing carbon material, the carbon material derived from thiourea and urea was synthesized by a polymerization process of the urea resin. No solid appeared after the polymerization process. When the dried sample after the polymerization process was heated in flowing N2 gas, we obtained carbon material. However, there was no product when only thiourea was heated under the same conditions. The percentages of nitrogen and sulfur in all the samples synthesized from thiourea were roughly 5-20 wt.% and 3-8 wt.% even after washing with hot water, respectively. No specific peak derived from the redox reaction appeared in the CV graphs for the samples. The capacitance value of T-urea800W, which was synthesized by the heat treatment at 800 °C and then wash with hot water, was 138.8 F g−1 at the current density of 50 mA g−1 in a 1 M H2SO4 water solution whereas that value of a commercial activated carbon was 107.1 F g−1 under the same conditions. It was presumed from the XPS measurements that the status of the nitrogen and sulfur in the materials are a pyridine-like nitrogen at the edge part of the graphitic structure, a quaternary nitrogen in the graphitic-layered structure, and S0, S4+, and S2−, respectively. 相似文献
142.
143.
Modeling of NBTI saturation effect and its impact on electric field dependence of the lifetime 总被引:1,自引:0,他引:1
H. Aono E. Murakami K. Okuyama A. Nishida M. Minami Y. Ooji K. Kubota 《Microelectronics Reliability》2005,45(7-8):1109-1114
Negative Bias Temperature Instability of pMOSFETs is investigated under various stress gate voltages and temperatures. It is shown that degradation tends to saturate and the dependence of lifetime on electric field (Eox) is expressed as a power-law of Eox. We propose new empirical and kinetic models. The Eox dependence of the lifetime described by the power-law is derived from our empirical model describing the saturation of degradation. Moreover, our kinetic model explains the saturation behavior. 相似文献
144.
Hydrogels that contain phosphate groups in side chains were studied for their usefulness in drug‐delivery soft contact lenses (SCLs). Naphazoline, a model drug having a cationic group, was incorporated into an SCL because of its phosphate groups and was released over a period of about 14 h. For the SCL, the naphazoline content was equivalent to the phosphate group content. It is suggested that drug‐delivery SCLs can be designed to contain the needed amount of a drug through the choice of the ionic group for the ligand. Furthermore, the SCL having amide groups and phosphate groups had high transparency and an unchanged shape. It is suggested that amide groups and phosphate groups must be introduced into the polymer in equimolar amounts to give the necessary polymer–drug interaction. Therefore, hydrogels having a drug‐delivery system were synthesized by the inclusion of a phosphate group and an amide group. These hydrogels are also applicable to SCL materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 731–735, 2005 相似文献
145.
Brain histamine mediates the bombesin-induced central activation of sympatho-adrenomedullary outflow
Intracerebroventricular (i.c.v.) administration of bombesin (0.3 nmol) increased plasma levels of both adrenaline and noradrenaline in urethane anesthetized rats. These bombesin-induced increases were inhibited by i.c.v. pretreatment with pyrilamine, an H1-receptor antagonist. Ranitidine, an H2-receptor antagonist also inhibited the increase of adrenaline, however, its effective dose was much larger than that of pyrilamine. Furthermore, the bombesin-induced increase of noradrenaline was not effectively inhibited by ranitidine. In the next series, turnover of histamine was assessed by measuring accumulation of tele-methylhistamine (t-MH), a major metabolite of brain histamine. I.c.v. administration of bombesin (0.3-3 nmol) increased turnover of hypothalamic histamine, while its intravenous administration was without effect. The present results suggest that the bombesin-induced central activation of sympatho-adrenomedullary outflow is probably, at least in part, mediated through brain histaminergic neurons. 相似文献
146.
Masugi Inoue Khaled Mahmud Homare Murakami Mikio Hasegawa Hiroyuki Morikawa 《Wireless Personal Communications》2005,35(1-2):53-70
A context-based adaptive communication system is introduced for use in heterogeneous networks. Context includes the user's
presence, location, available network interfaces, network availability, network priority, communication status, terminal features,
and installed applications. An experimental system was developed to clarify the feasibility of using context information to
flexibly control networks and applications. The system operates on a seamless networking platform we developed for heterogeneous
networks. By using contexts, the system can inform the caller and callee of applications they can access, which are available
through the network before communication occurs. Changes in contexts can switch an on-going application to another during
actual communication. These functions provide unprecedented styles of communication. A business scenario for a seamless networking
provider is also presented.
Dr. Morikawa has also been in charge of NICT's Mobile Networking Group.
Masugi Inoue received his B.E. from Kyoto University in 1992 and his M.E. and D.E. from the University of Tokyo in 1994 and 1997, all
in the field of Electrical Engineering. He is currently a senior researcher at the Yokosuka Radio Communications Research
Center under the National Institute of Information and Communications Technology (NICT), Japan, and has been engaged in R&D
on ultrahigh-speed WLANs and mobile networking. He joined the Communications Research Laboratory (CRL) of the Ministry of
Posts and Telecommunications, Japan, in 1997, which was reorganized as NICT in April 2004. He was a visiting researcher at
Polytechnic University in Brooklyn, New York in 2000.
Khaled Mahmud received his B.Sc. (Eng.) in Electrical and Electronics Engineering from the Bangladesh University of Engineering and Technology
in Dhaka in 1991. He received his M.E. and Ph.D. in the same field from Shizuoka University in Japan, in 1997 and 2000, respectively.
He was a research fellow at NICT, Japan, from 2000 to 2004. He is currently an Assistant Professor in the Department of Computer
Science and Engineering at North South University, Bangladesh. His research interests include modulation-demodulation techniques,
software radio, mobile communication systems, wireless Internet, and IP mobility technologies.
Homare Murakami received his B.E. and M.E. in Electronic Engineering from Hokkaido University in 1997 and 1999. In 2004, he received the
Young Investigators Award from IEICE. He is currently a researcher at NICT's Mobile Networking Group. He is also an industrial
PhD student in Aalborg University since 2003. His interest areas are naming scheme, wireless TCP and new transport protocol,
IP mobility, fast handover method, and location management.
Mikio Hasegawa received his B. Eng, M. Eng., and Dr. Eng. in 1995, 1997, and 2000 from Science University of Tokyo. From 1997 to 2000, he
was a Research Fellow of the Japan Society for the Promotion of Science (JSPS). He is currently a senior researcher in Mobile
Networking Group, National Institute of Information and Communications Technology, and a technical advisor in ChaosWare Inc.
His research interests include applications of chaotic dynamical theory, combinatorial optimization, mobile networks, and
ubiquitous computing.
Hiroyuki Morikawa received his B.E., M.E., and D.E. in Electrical Engineering from the University of Tokyo in 1987, 1989, and 1992. He is currently
an Associate Professor in the Department of Frontier Informatics at the University of Tokyo and is in charge of NICT's Mobile
Networking Group. His research interests are in the areas of computer networks, mobile computing/networks, ubiquitous computing,
and network services. He serves as Editor of Transactions of the IEICE and has been on the technical program committees of
IEEE/ACM conferences and workshops. He sits on numerous telecommunications advisory committees and frequently serves as a
consultant to the government. 相似文献
147.
CN Kaneto AJ Costa AC Paulillo FR Moraes TO Murakami MV Meireles 《Canadian Metallurgical Quarterly》1997,69(3-4):203-210
To evaluate chicken toxoplasmosis both as an economic and a public health subject, 84 broiler chicks of a commercial strain, 30 days old, were distributed into seven groups of 12 birds (three replications of four chicks) experimentally infected with three developing T. gondii stages of the P strain as follows: tachyzoites, intravenous (two groups: 5.0 x 10(5) and 5.0 x 10(6)), cysts, per os (two groups: 1.0 x 10(2) and 1.0 x 10(3)) and oocysts, per os (three groups: 5.0 x 10(2), 5.0 x 10(3) and 5.0 x 10(4)). Twelve chicks received only a placebo (control group). During the next 30 days the following parameters were estimated: productivity (weight gain and feed conversion), clinical signs, including rectal temperature and parasitemia (bioassay). No clinical signs suggesting toxoplasmosis were seen and no statistical differences on productivity standards were found in comparison between inoculated and control chicks. However, fowls inoculated with tachyzoites and oocysts occasionally showed hyperthermia. Some haematological changes were detected in fowls inoculated with T. gondii. Anatomo-histopathological changes were not observed. From 14 parasitemias detected, 35.7% appeared on the 5th day after inoculation and 57.1% of them resulted from oocysts inoculation. After 30-35 days all birds were slaughtered: fragments from 12 organs or tissues from each of them were subjected to artificial peptic digestion and after that injected into T. gondii antibody-free mice (IIFR). T. gondii was detected in brain (12), pancreas (five), spleen (five), retina (five), kidney (two), heart (four), proventriculus (three), liver (two), intestine (two), lung (one), and skeletal muscle (one). Similar to observations with parasitemia, from 42 T. gondii isolations, 59.5% came from chicks which had received oocysts. It can thus be inferred that the developing form, expelled by cats, is the most important for T. gondii chicken infection and that brain is the most infected organ in birds. Attention must be paid to the potential importance of chicken meat in public health, since T. gondii was isolated from skeletal and heart muscles. 相似文献
148.
M Hibi A Matsuura H Ohshima Y Tomida F Murakami K Yoshida M Kawamura 《Canadian Metallurgical Quarterly》1998,51(2):106-107
A 24-year-old white man had a six-month history of nontender nodules on the dorsal aspect of the right hand. The lesions were diagnosed as lymphocutaneous sporotrichosis based on clinical appearance, histopathologic examinations, and fungal culture. Therapy with itraconazole was started. Considerable improvement was recorded after two months, when all of the lesions diminished in size and were no longer nodular in appearance. 相似文献
149.
150.
H Iwamoto F Katoh T Gotoh S Nishimura Y Ono Y Nishio E Fukuhara T Murakami 《Canadian Metallurgical Quarterly》1998,39(5):589-595
Histochemical studies of mammary gland sections obtained from healthy lactating Prim' Holstein cows contained numerous corpora amylacea, mainly located in active alveoli. Observations by electron microscopy revealed a cauliflower shape, with a fibrillar or multilayered organization. Mineral studies confirmed the presence of high calcium levels (12.3% of dry matter) and phosphorus (7.4%) in the corpora amylacea composition. These bodies stained positive to Von Kossa silver nitrate and to Periodic acid-Schiff. However, depending on the gland of origin, corpora amylacea stained positive or negative to Congo red. Histochemical studies seemed, therefore, insufficient to determine the presence or absence of amyloid. The amount of total protein varied by approximately 25%. Immunoblotting and analysis of the amino acid sequence of a peptidic fragment obtained from corpora amylacea gave clear evidence of the occurrence of caseins, beta-lactoglobulin and alpha-lactalbumin. However, the comparison between the amino acid composition of corpora amylacea and those of the main milk proteins indicated the presence of other proteins. Electrophoretic analysis also gave evidence of the presence of several other proteins, i.e. glycoproteins. Therefore, it is probable that corpora amylacea composition is much more complex than previously reported. 相似文献