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91.
Hideki Wada Fumio YamamotoKenji Ueta Toshiyuki Yamaguchi 《Solar Energy Materials & Solar Cells》2011,95(1):382-385
We report analysis about generation data of a 100 kW PV system. The system consists of seven polycrystalline silicon arrays and three thin-film arrays. The rated power of each array is 10 kW. Thin-film is made of tandem structure comprising amorphous silicon and microcrystalline silicon. For each array, tilt angles are arranged in 10°, 20° or 30°. And directions are facing due south, south-south east 30° and south-south west 30°.We have been analyzing generation data of the system since 2007 to understand the influence of system arrangement. The knowledge we have got until now is below.
- (a)
- Seasonal annealing occurs in thin-film arrays because thin-film cells contain amorphous silicon. Thus, theoretically, as for reduction of conversion efficiency in high temperature season, reduction of thin-film arrays is smaller than polycrystalline’s. We analyzed the ratio of seasonal generation energy (kWh) by using measured data of the system. Generation energy ratio in summer of thin-film is larger than polycrystalline’s. This is same trend as the theory.
- (b)
- There is a simulated data of solar irradiation that had been calculated by using meteorological data of 30 years. According to this simulated data, optimum condition of the system is arranged in tilt angle of 28.4° and facing due south. (The system is situated at latitude 33° north.) And simulation data shows that yearly irradiation decreases as tilt angle and direction become far from optimum condition. We analyzed yearly generation energy of each array in the system. Each array’s reduction percentages of generated energy from optimum condition were smaller than simulation value.
92.
Kumata H Mori M Takahashi S Takamiya S Tsuzuki M Uchida T Fujiwara K 《Environmental science & technology》2011,45(23):9990-9997
To propose new molecular markers for tire-wear emissions, four dihydroresin acids, that is, 8-isopimaren-18-oic acid (I), 8-pimaren-18-oic acid (II), 13β(H)-abieten-18-oic acid (III), and 13α(H)-abiet-8-en-18-oic acid (IV), were identified and investigated for source specificities, distributions, and environmental stabilities. The absence of I-IV in natural sources and the linear correlations between dihydroresin acids with different skeletons in tires and in environmental samples demonstrated that I-IV are specific markers for synthetic rubbers. The ratio of III + IV to the sum of III + IV plus abietic acid showed the resin acids distribution between different environmental compartments receiving contributions from traffic and natural sources. The physicochemical properties and results of photolysis experiments suggested that I-IV can set lower limits for tire-wear contributions to environmental loads of particulate matter (PM) and polycyclic aromatic hydrocarbons with molecular weight ≥202. By comparing III + IV concentrations or (III+IV)/pyrene or (III+IV)/benzo[a]pyrene ratios in tires and those in environmental matrices, the contributions of tire-wear emissions to PM, pyrene, and benzo[a]pyrene were estimated to be 0.68 ± 0.54%, 6.9 ± 4.8%, and 0.37 ± 0.18% in roadside PM and 0.83 ± 0.21%, 0.88 ± 0.52%, and 0.08 ± 0.06% in rooftop PM. 相似文献
93.
Ryohei?MoriEmail author Tsutomu?Ueta Kazuo?Sakai Yasuhiro?Niida Yasuko?Koshiba Li?Lei Katsuhiko?Nakamae Yasukiyo?Ueda 《Journal of Materials Science》2011,46(5):1341-1350
In order to prepare the TiO2 liquid dispersions for the electrodes of dye-sensitized solar cells with industrial mass production level at a reasonable
cost, the present study investigates the preparation of TiO2 liquid dispersions by a general industrial dispersion technique using readily available P25. To determine the TiO2 dispersion offering the best light–electricity energy conversion efficiency, the suitability of various types of solvents
and resins for use in TiO2 dispersion are tested. In general, organic solvent based TiO2 dispersions are found to allow the formation of more uniform thin films in comparison with water-based dispersions. A preparation
using ethyl cellulose as the resin and the terpineol as the solvent is found to exhibit the best conversion efficiency. We
have also found that using two kinds of resins of different molecular weights gave rise to better efficiency. Among 26 metal
compounds tested in this study, the best metal dopant was Ag. XRD and XPS measurements confirm that the Ag exists as metal
Ag and silver oxide. 相似文献
94.
Shinya Aikawa Rong Xiang Erik Einarsson Shohei Chiashi Junichiro Shiomi Eiichi Nishikawa Shigeo Maruyama 《Nano Research》2011,4(6):580-588
Field-effect transistors (FETs) have been fabricated using as-grown single-walled carbon nanotubes (SWNTs) for the channel
as well as both source and drain electrodes. The underlying Si substrate was employed as the back-gate electrode. Fabrication
consisted of patterned catalyst deposition by surface modification followed by dip-coating and synthesis of SWNTs by alcohol
chemical vapor deposition (CVD). The electrodes and channel were grown simultaneously in one CVD process. The resulting FETs
exhibited excellent performance, with an I
ON/I
OFF ratio of 106 and a maximum ON-state current (I
ON) exceeding 13 μA. The large I
ON is attributed to SWNT bundles connecting the SWNT channel with the SWNT electrodes. Bundling creates a large contact area,
which results in a small contact resistance despite the presence of Schottky barriers at metallic-semiconducting interfaces.
The approach described here demonstrates a significant step toward the realization of metal-free electronics.
相似文献
95.
Naofumi Ohtsu Manabu Hayashi Junpei Ueta Toru Kanno 《Progress in Organic Coatings》2011,70(4):353-357
The present study investigates the effect of the heating temperature on the characteristics of the surface layer in a simple treatment process using calcium-hydroxide slurry. Furthermore, biofunctions of the treated titanium surfaces, such as bioactivity in a simulated body fluid and corrosion resistance under a bio-environment, are also investigated. Our treatment process using calcium-hydroxide slurry is as follows: a titanium substrate is buried in calcium hydroxide slurry, and the slurry is then heated in air. The calcium hydroxide slurry was prepared by mixing of calcium hydroxide powder and water. When treated at heating temperature beyond 873 K, a crystallized calcium titanate coating is formed on a titanium substrate and further, the thickness increases with the increase of heating temperature. On the crystallized calcium titanate coating, calcium phosphate is precipitated in a simulated body fluid; therefore, the treated titanium surface has bioactivity. Furthermore, anodic current density of the treated surface is 10–103 times lower than that of the non-treated surface. 相似文献
96.
Intraarterial chemotherapy combined with radiation therapy for advanced cancer of the uterine cervix
M Noguchi R Murata T Sagoh M Yamamoto H Ueda K Kinoshita M Ueta H Honda K Miyazaki T Sasaki T Tachibana 《Canadian Metallurgical Quarterly》1998,25(9):1314-1317
The results of intraarterial chemotherapy (IACT) combined with definitive radiation therapy for 23 advanced and bulky carcinomas of uterine cervix are reported. IA-CT with cisplatin 50 mg and doxorubicin 30 mg was administered by one shot method in bilateral internal iliac arteries. The protocol consisted of one to three treatment session every 3 weeks. Nine of eleven patients with clinical stage III achieved a complete local response (82%), and the 3- and 5-year survival in these cases were 72% and 72%, respectively. These results were superior to the response (58%), 3- and 5-year survivals (68%, 58%) obtained in 19 patients treated mainly with radiation therapy alone. The side effect of grade 2 and 3 for the intestine, such as ileus and hemorrhagic colitis, was noted in 3 patients (15%). In addition, 3 of 8 patients with radical surgery and postoperative radiation therapy after IA-CT developed insufficient fracture of pelvic bone. These complications accompanied by IA-CT combined with radiation therapy and/or surgery increased slightly, compared with that by the previous therapy without IA-CT, but were not critical. The results suggest that IA-CT following radiation therapy is effective to improve the prognosis of patients with Stage III cervical cancer. 相似文献
97.
98.
I Shibuya N Kabashima K Tanaka VS Setiadji J Noguchi N Harayama Y Ueta H Yamashita 《Canadian Metallurgical Quarterly》1998,10(10):759-768
In neurosecretory cells of the supraoptic nucleus (SON) of rats, pituitary adenylate cyclase activating polypeptide (PACAP) causes an increase in [Ca2+]i, and stimulates somatodendritic vasopressin (VP) release. In this report, to elucidate the ionic mechanism of the action of PACAP, membrane potentials and ionic currents were measured from SON neurones in slice preparations or from dissociated SON neurones. In the current clamp mode, PACAP depolarized membrane potentials of both phasic and non-phasic neurones and increased the firing rate. Moreover, simultaneous measurements of membrane potentials and [Ca2+]i revealed that the membrane depolarization correlated well with increases in [Ca2+]i. In the voltage-clamp mode, PACAP induced inward currents at a holding potential of -70 or -80 mV in a dose-dependent manner and the time course of the currents was similar to that of the PACAP-induced membrane depolarization. The averaged reversal potential of the PACAP-induced currents obtained from dissociated SON neurones was -33 mV, which was close to the reversal potential of non-selective cation currents in SON neurones. The currents were rapidly and reversibly inhibited by a cation-channel blocker, gadolinium. Analysis of synaptic inputs into SON neurones in slice preparations revealed that PACAP had little or no effects on the frequency of spontaneous excitatory and inhibitory postsynaptic currents. These results suggest that pituitary adenylate cyclase activating polypeptide (PACAP) activates PACAP receptors in the postsynaptic membrane of the supraoptic nucleus (SON) neurones, and that the activation of PACAP receptors leads to opening of non-selective cation channels, depolarization of the membrane potential, and increase in the firing rate in SON neurones. Such mechanisms may account for the PACAP-induced increase in [Ca2+]i and vasopressin (VP) release observed in SON neurones. 相似文献
99.
100.
Yoshinobu Naoshima Hiroshi Mukaidani Shohei Shibayama Toshiya Murata 《Journal of chemical ecology》1986,12(1):127-133
A nine-step synthesis is described for a diastereomeric mixture of 15,19,23-trimethylheptatriacontane, a contact sex pheromone ofGlossina morsitans morsitans Westwood. The compound has been synthesized by means of double alkylation of diethyl 3-oxoglutarate (DEOG) with 3-methyl-2-heptadecenyl methanesulfonate, which was readily prepared from 1-hexadecene, as the key step.This study constitutes Part XII of Selective Alkylation of Diethyl 3-Oxoglutarate. Part XI of this series, see Naoshima et al. (1984). 相似文献