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41.
Broadband four-wave mixing generation in short optical fibres 总被引:1,自引:0,他引:1
Aso O. Shin-Ichi Arai Yagi T. Tadakuma M. Suzuki Y. Namiki S. 《Electronics letters》2000,36(8):709-711
Several advantages of using a short length of fibre to generate broadband four-wave mixing are proposed and verified using wavelength conversion experiments for different lengths of a previously developed high-nonlinearity fibre with a nonlinear coefficient of 13.8 W-1 km-1. Consequently, 91.3 nm broadband simultaneous wavelength conversion is demonstrated using a 100 m long section of the developed fibre 相似文献
42.
We investigated slip and unstable flow phenomena of polystyrene melts in capillaries from the view of the effects of temperature and molecular weight by using three polystyrene samples with different molecular weights (Mw = 192,000, Mw = 258,000, and Mw = 321,000). The slip velocities are estimated by the Mooney method and the modified Mooney method. We found that the slip velocity increases and the critical slip stress above which a slip starts to occur decreases with the temperature. We also observed the melt-fracture at above a critical melt-fracture stress higher than . We found that the onset of melt fracture is affected by the extensional stress near the entry region to the capillary in the barrel and the melt-fracture tends to easily occur with increase of the molecular weight, but is not sensitive to the temperature. 相似文献
43.
Effects of rice straw returning methods on N<Subscript>2</Subscript>O emission during wheat-growing season 总被引:1,自引:0,他引:1
Erdeng Ma Guangbin Zhang Jing Ma Hua Xu Zucong Cai Kazuyuki Yagi 《Nutrient Cycling in Agroecosystems》2010,88(3):463-469
A field experiment was conducted in Jurong of Nanjing, Jiangsu Province, China from 2006 to 2008 to investigate N2O emission during the wheat-growing season as affected by various rice straw returning methods prior to wheat cultivation.
The study was designed to have four treatments: no rice straw applied (CK), rice straw burnt in situ (RB), rice straw evenly
incorporated into the topsoil (RI), rice straw evenly spread over the field as mulch (RM). Results showed that N2O emission was decreased by 24–29% in Treatment RB and by 3–18% in Treatment RI, but increased by 15–39% in Treatment RM,
compared with that in Treatment CK. The contents of soil total C and N at wheat harvest were significantly increased by 7–13%
and by 8–12% in Treatment RI, respectively, compared with that in Treatment CK. The wheat grain yield in Treatment RI was
1.0–1.2 times that in the Treatment CK. Based on these results, the best management practice of returning rice straw to the
soil prior to wheat cultivation is evenly incorporating rice straw into the topsoil, as the method tended to reduce N2O emission during the wheat-growing season and increase wheat yield and soil fertility. 相似文献
44.
Novel transdermal drug delivery system with polyhydroxyalkanoate and starburst polyamidoamine dendrimer 总被引:1,自引:0,他引:1
Wang Z Itoh Y Hosaka Y Kobayashi I Nakano Y Maeda I Umeda F Yamakawa J Kawase M Yag K 《Journal of Bioscience and Bioengineering》2003,95(5):541-543
In search of an efficient transdermal drug delivery system (TDDS), a polyhydroxyalkanoate (PHA)-based system with a polyamidoamine dendrimer was examined. Tamsulosin was used as the model drug. The dendrimer was found to act as the weak enhancer. By adding the dendrimer, the dendrimer-containing PHA matrix achieved the clinically required amount of tamsulosin permeating through the skin model. This is also the first report of the application of PHA and dendrimer to the TDDS. 相似文献
45.
Y Mizukami T Nagashima K Ikuta E Chikamatsu K Kurachi H Kanemoto T Yagi S Ohhira Y Nimura 《Canadian Metallurgical Quarterly》1998,45(23):1462-1467
Gallbladder carcinoid is a rare disease. In previous reports, classical carcinoid, an entity with a good prognosis, has not been distinguished from endocrine cell carcinoma, a tumor associated with marked cell atypia and mitosis, and a poor prognosis. The patient was a 66 year old woman who presented to our hospital with a chief complaint of jaundice. Pre-operatively, she was diagnosed as having advanced gallbladder carcinoma invading the liver and the hepatic hilus. The patient underwent right hepatic trisegmentectomy with en bloc resection of the caudate lobe and extrahepatic bile ducts, extended lymph node clearance and left hepaticojejunostomy. Histopathological examination showed positive Grimelius staining, marked mitosis, and intense atypism, hence, the tumor was diagnosed as an endocrine cell carcinoma. Twelve years after surgery, the patient is healthy, without any sign of recurrence. We present this novel case of long-term survival and review the literature. 相似文献
46.
Hiroyuki Fujishiro Manabu Ikebe Masayuki Yagi Kiminari Nakasato Yuzo Shibazaki Tetsuo Fukase 《Journal of Low Temperature Physics》1996,105(3-4):981-986
The thermal conductivity of high density La2–xMxCuO4 (M=Ba, Sr) sintered materials was measured between 15K and 150K for the various concentrations of Ba and the phonon thermal conductivity was analyzed comparing with that of Nd2–xCexCuO4. The pretty large value for pure La2CuO4 was drastically diminished by substituting La by a small amount of Ba atoms especially at low temperatures. It was found that a new type of the phonon scattering center such as a two-level tunneling must be taken account of in order to explain the observed reduction. 相似文献
47.
We address the balanced clustering problem where cluster sizes are regularized with submodular functions. The objective function for balanced clustering is a submodular fractional function, i.e., the ratio of two submodular functions, and thus includes the well-known ratio cuts as special cases. In this paper, we present a novel algorithm for minimizing this objective function (submodular fractional programming) using recent submodular optimization techniques. The main idea is to utilize an algorithm to minimize the difference of two submodular functions, combined with the discrete Newton method. Thus, it can be applied to the objective function involving any submodular functions in both the numerator and the denominator, which enables us to design flexible clustering setups. We also give theoretical analysis on the algorithm, and evaluate the performance through comparative experiments with conventional algorithms by artificial and real datasets. 相似文献
48.
Keita Yagi Junji Murata Yasuhisa Sano Hidekazu Goto 《Science and Technology of Advanced Materials》2007,8(3):166-169
The copper damascene process is one of the most promising technologies for fabricating Cu wirings for electronic devices such as LSIs. In this research, the fabrication of damascene Cu wirings was conducted using solid acidic catalyst. When a Cu-plated wafer, whose oxide is a basic oxide is dipped into a mixture of oxidizing solution and acidic solution, surface atoms are ionized and etched off into the solution. However, because conventional nonelectrolytic etching does not have a reference surface, it is difficult to utilize for planarization. Therefore, a new nonelectrolytic machining method using a cation-exchange fabric instead of an acidic solution was developed. To be more precise, the planarization of a Cu-plated wafer was carried out by rubbing with the cation-exchange fabric in ozone water. Basically, this method exploits chemical reactions so that the physical properties of the workpiece surface are not deteriorated. Furthermore, this method uses no chemicals except for ozone water, which easily dissociates into water and oxygen molecules; thus, this method is a low-cost, environmentally friendly process. In this paper, as a preliminary experiment, the nonelectrolytic etching of a Cu sample using solutions of O3 and CO2 was carried out to inspect the dependence of the etching rate on [O3] and [H+]. The results indicate that the etching rate increased as [O3] and [H+] increased. When [H+] was high relative to [O3], a smooth etch-pit-free surface was achieved. Next, nonelectrolytic etching using a cation-exchange fabric was carried out, and properties similar to those in the case of etching using solutions were obtained. Finally, damascene Cu wirings were fabricated using ozone water and a cation-exchange catalyst. 相似文献
49.
H Wakita Y Tokura H Yagi K Nishimura F Furukawa M Takigawa 《Canadian Metallurgical Quarterly》1994,286(6):350-354
Antibody titres against Plasmodium falciparum and P. vivax were examined using the indirect fluorescent antibody test (IFAT) for 183 Gidra-speaking adults and adolescents in four ecologically different villages of lowland Papua New Guinea. The findings highlight that 1) in Gidraland P. falciparum was more prevalent than P. vivax, 2) the proportion of antibody titres of 1:64 or higher markedly differed among the villages, ranging from 35.3% to 100% for males and from 31.6% to 100% for females, and 3) in the two villages with high prevalences, these were higher among males than females. The inter-village and sex differences can be largely explained by microenvironmental conditions and behavioural patterns of the population. The population-based analyses of this study intend to contribute to a better understanding of the prevalence of malaria in human-environment settings and thus to the planning of malaria prevention. 相似文献
50.
In order to obtain information on the lattice location of B atoms in graphite, channelling experiments have been performed at room temperature with a proton beam of an energy of 0.65-0.77 MeV for the 〈0 0 0 1〉 axial channel in highly oriented pyrolytic graphite (HOPG) crystals doped with 0.32 at.% B. The B atoms are detected by measuring α-particles which are emitted as a result of a nuclear reaction 11B(p,α)αα. It is clearly demonstrated that most of B atoms are shadowed behind the 〈0 0 0 1〉 C atomic rows. Taking account of the already reported experimental results on a change of lattice parameters by B-doping, it is concluded that most of B atoms are located at substitutional sites. It is also observed that B-doping introduces lattice strain on the c-plane. In addition, the presence of a small portion of interstitial B atoms is suggested. 相似文献