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71.
Supachai Ngamsinlapasathian Thammanoon Sreethawong Yoshikazu Suzuki Susumu Yoshikawa 《Solar Energy Materials & Solar Cells》2006,90(14):2129-2140
The effects of indium tin oxide (ITO) and ITO/SnO2 conducting substrates on photovoltaic properties of dye-sensitized solar cells (DSCs) using nanocrystalline TiO2 were studied. The decrease in fill factor of the DSCs was correlated to the increase in resistance of conducting substrate. The heat stability of ITO conducting glass was improved by depositing SnO2 on ITO layer. The efficiency of the cells using double layered ITO/SnO2 substrate remarkably increased comparing with that of the cells using ITO substrates. It is worth mentioning that increasing in sintering time, which enhanced the electronic contact between substrate and TiO2, also modified the cell performance of MP-TiO2 cells. Our experimental finding suggests that 3000 Å ITO substrate, which was covered by 1000 Å SnO2 layer, exhibited the best properties for the DSCs. 相似文献
72.
Scintillation properties of Tm-doped Lu3Al5O12 single crystals 总被引:1,自引:0,他引:1
Makoto Sugiyama Yutaka Fujimoto Takayuki Yanagida Daisuke Totsuka Yuui Yokota Akira Yoshikawa 《Optical Materials》2011,34(2):439-443
Using the micro-pulling-down (μ-PD) method, Tm-doped Lu3Al5O12 (Tm:LuAG) single crystals were grown to examine their scintillation properties. In transmittance spectra, they exhibited about 80% transparency in the wavelengths longer than 320 nm and five absorption lines due to Tm3+ 4f–4f transitions were observed. 241Am α-ray excited radioluminescence spectra were measured and intense 4f–4f emission peaks were observed with the host emission. When excited by 137Cs γ-Ray to obtain pulse height spectra, Tm 1% doped LuAG showed the highest light yield coupled with a photomultiplier (PMT) or a silicon avalanche photodiode (Si-APD). The light yield was estimated to be 5800 and 7300 photons/MeV for PMT and Si-APD, respectively. Decay time profiles consist of two exponential components and the fast and slow components are considered to be attributed to the host and the combination of the host and Tm3+ 4f–4f emission, respectively. 相似文献
73.
Makoto Sugiyama Yutaka FujimotoTakayuki Yanagida Yuui YokotaJan Pejchal Yuki FuruyaHidehiko Tanaka Akira Yoshikawa 《Optical Materials》2011,33(6):905-908
Nd 0.1%, 0.5%, 1% and 3% doped Lu3Al5O12 (Nd:LuAG) single crystals were grown in the nitrogen atmosphere by the micro-pulling down (μ-PD) method. The grown crystals had a single-phase confirmed by powder XRD analysis. In absorption spectra, some weak absorption lines due to Nd3+ 4f-4f transitions were observed and their intensity increased with the increase of Nd concentration. When excited by 241Am α-ray, a broad emission peak due to defects in the host lattice at 320 nm and some sharp lines due to Nd3+ 4f-4f transitions at wavelength longer than 400 nm were observed. The decay time profiles of Nd:LuAG under γ-ray excitation were well approximated by two exponential function of 340-760 ns and 3-5 μs for each sample. By pulse height measurement using 137Cs, Nd 0.5%:LuAG showed the highest light yield of 7600 ± 760 photons/MeV. 相似文献
74.
Kumaki Y Ogawa M Hirano T Yoshikawa K Iwasawa N Yagi T Hakamata W Oku T Nishio T 《Journal of Bioscience and Bioengineering》2011,111(2):134-139
The chromosomal DNA of the syntrophic thermophile Symbiobacterium thermophilum contains open reading frames of the genes encoding family M42 aminopeptidases, Pep1079, Pep1080, and Pep1081. To characterize these peptidases, the genes were cloned into Escherichia coli and overexpressed. Our experiments using the recombinant proteins confirmed that Pep1079, Pep1080, and Pep1081 are components of arginyl or lysinyl aminopeptidases that require Co2+ for enzymatic activity. Coexistence of Pep1079 and Pep1080 is necessary for expressing high peptidase activity. Pep1081 enhances the activity of Pep1079 and Pep1080. 相似文献
75.
Yoshikawa M Seki H Inoue K Matsuda K Tanahashi Y Sako H Nanen Y Kato M Kimoto T 《Applied spectroscopy》2011,65(5):543-548
We used Fourier transform infrared (FT-IR) spectroscopy to characterize silicon dioxide (SiO(2)) films on a 4H-SiC(0001) Si face. We found that the peak frequency of the transverse optical (TO) phonon in SiO(2) films grown on a 4H-SiC substrate agrees well with that in SiO(2) films grown on a Si substrate, whereas the peak frequency of the longitudinal optical (LO) phonon in SiO(2) films on a 4H-SiC substrate is red-shifted by approximately 50 cm(-1) relative to that in SiO(2) films on a Si substrate. We concluded that this red-shift of the LO phonon is mainly caused by a change in inhomogeneity due to a decrease in density in the SiO(2) films. Furthermore, cathodoluminescence (CL) spectroscopy results indicated that the channel mobility of the SiC metal-oxide-semiconductor field-effect transistor (MOSFET) decreases roughly in proportion to the increase in the intensity of the CL peak at 460 and 490 nm, which is attributed to the increase in the number of oxygen vacancy centers (OVCs). FT-IR and CL spectroscopies provide us with a large amount of data on OVCs in the SiO(2) films on a 4H-SiC substrate. 相似文献
76.
Y Makino K Okamoto N Yoshikawa M Aoshima K Hirota J Yodoi K Umesono I Makino H Tanaka 《Canadian Metallurgical Quarterly》1996,98(11):2469-2477
77.
Y Inoue T Ohtake Y Homma K Yoshikawa J Nishikawa Y Sasaki 《Canadian Metallurgical Quarterly》1998,39(10):1784-1788
We describe a method to evaluate glomerular filtration rate (GFR) in both children and adults using 99mTc-diethylenetriamine pentaacetic acid (DTPA) and a gamma camera. METHODS: Renal scintigraphy with 99mTc-DTPA was performed in 40 children and 92 adults with various degrees of renal function. The percent renal uptake at 2-2.5 min after tracer arrival in the kidney was determined with background subtraction and correction for soft-tissue attenuation and was correlated by linear regression analysis with GFR measured from two blood samples. A perirenal region of interest was used for background subtraction. Renal depth was computed using the equations determined or validated on the basis of CT measurements, and the attenuation coefficient was set at 0.12. The obtained regression equation was used to predict GFR. Renal function was also assessed by the Gates' method. RESULTS: Percent renal uptake was closely correlated with GFR normalized for body surface area in all patients (y = 15.958x - 2.94; r = 0.939). GFR was successfully predicted using the regression equation in both children and adults. Gates' method severely overestimated GFR in children and provided less accurate values even in adults than our method. CONCLUSION: The method presented here requires neither blood sampling nor additional imaging and allows estimation of GFR in both children and adults. 相似文献
78.
The adherence of neutrophils to the endothelium is a crucial early event in the inflammatory and immunological reaction. Neutrophil-endothelial cell interactions are known to be mediated by adhesion molecules that are expressed on each cell. Among the adhesion molecules expressed on leukocytes, the CD11/CD18 integrin family plays a major role in the adhesion and transendothelial migration of neutrophils. The two most extensively characterized endothelial cell adhesion molecules are intercellular adhesion molecule-1 and E-selectin. These adhesion molecules are involved in the pathogenesis of several digestive diseases such as Helicobacter pylori, non steroidal anti inflammatory drug- or stress-induced gastric mucosal injury, inflammatory bowel diseases. 相似文献
79.
Kirihata T. Dhong S.H. Kitamura K. Sunaga T. Katayama Y. Scheuerlein R.E. Satoh A. Sakaue Y. Tobimatsu K. Hosokawa K. Saitoh T. Yoshikawa T. Hashimoto H. Kazusawa M. 《Solid-State Circuits, IEEE Journal of》1992,27(9):1222-1228
A 4-Mb high-speed DRAM (HSDRAM) has been developed and fabricated by using 0.7-μm L eff CMOS technology with PMOS arrays inside n -type wells and p-type substrate plate trench cells. The 13.18-mm×6.38-mm chip, organized as either 512 K word×8 b or 1 M word×4 b, achieves a nominal random-access time of 14 ns and a nominal column-access time of 7 ns, with a 3.6-V V cc and provision of address multiplexing. The high level of performance is achieved by using a short-signal-path architecture with center bonding pads and a pulsed sensing scheme with a limited bit-line swing. A fast word-line boosting scheme and a two-stage word-line delay monitor provide fast word-line transition and detection. A new data output circuit, which interfaces a 3.6-V V cc to a 5-V bus with an NMOS-only driver, also contributes to the fast access speed by means of a preconditioning scheme and boosting scheme. Limiting the bit-line voltage swing for bit-line sensing results in a low power dissipation of 300 mW for a 60-ns cycle time 相似文献
80.
OBJECTIVE: To investigate the prevalence of coronary artery disease (CAD), atherothrombotic brain infarction (ABI), and peripheral arterial disease (PAD) in older Hispanics and the association with risk factors in this population. DESIGN: A retrospective analysis of charts from all Hispanics seen during January 1996 through July 1997 at an academic hospital-based geriatrics practice. SETTING: An academic, hospital-based, primary care geriatrics practice staffed by fellows in a geriatrics training program and by full-time faculty geriatricians. PATIENTS: One hundred sixty women and 53 men, mean age 80 +/- 8 years (range 64 to 100), were included in the study. MEASUREMENTS AND MAIN RESULTS: Of 213 Hispanics in the study, 59 (28%) had documented CAD, 43 (20%) had ABI, 34 (16%) had PAD, and 90 (42%) had either CAD, ABI, or PAD. Serum total cholesterol and triglycerides were measured in 202 of 213 subjects (95%). Serum high-density lipoprotein cholesterol was measured in 137 of 213 patients (64%). Other risk factor data were documented in all patients. Multiple logistic regression analysis performed in 202 patients using the variables age, gender, cigarette smoking, hypertension, diabetes mellitus, obesity, serum total cholesterol, and serum triglycerides showed statistically significant associations between prevalent CAD, ABI, or PAD and age (P = .002, odds ratio (OR) = 1.083), cigarette smoking (P = .002, (OR) = 3.865), hypertension (P = .007, (OR) = 2.749), diabetes mellitus (P = .028, (OR) = 2.386), obesity (P = .014, (OR) = 2.608), serum total cholesterol (P < 0.001, (OR) = 1.025), and serum triglycerides (P = .017, (OR) = .993). CONCLUSIONS: Either CAD, ABI, or PAD was present in 42% of 213 older Hispanics. There were statistically significant associations between prevalent CAD, ABI, or PAD in older Hispanics and risk factors, including age, cigarette smoking, hypertension, diabetes mellitus, obesity, and serum total cholesterol. 相似文献