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51.
Characterization of the differences and algal-available fractions of P in soils, suspended solids, and bottom sediments have been the main topics of research during the past decade. However, the size distribution and properties of particulate matter in runoff have not been much studied in Japan. Here we study particle size distribution during runoff and the chemical characteristics of P in each soil size fraction and relate them to land use. The temporal variation of particulate sizes during rain events is different in each watershed. Most particles have the size in the range of 10-100 microm. Also, the percentage of BAP in TP as well as percentage of PCOD in SS also varies temporally and spatially during runoff. To investigate how soil particles characteristics depend on land use, soil samples from two watersheds are examined. For particle size distribution and specific gravity, no significant difference among watersheds is found. However, C, N, and P content are indirectly proportional to the particle size, which means smaller particle size results in larger. H2O-extracted P, NH4Cl-extracted P, NAI-P, Apatite-P, Organic-P, and TP contents in each soil particle sample vary depending on particle size, land use, and watershed. 相似文献
52.
53.
Yasuda K Nakamoto T Yasuhara M Okada H Nakajima T Kanzaki H Hori M Ozaki H 《Reproduction (Cambridge, England)》2007,133(4):797-806
To assess the role of protein kinase Cbeta (PKCbeta) in human myometrial contractions during pregnancy, we evaluated the effect of a PKCbeta inhibitor (LY333531) on the pregnant and nonpregnant myometrial contractions and compared the level of PKCbeta in the pregnant myometrium with that in the nonpregnant myometrium. The effects of LY333531 on the myometrial contractions were examined by measuring contractile activity (frequency and amplitude). PKCbeta in human myometrium was assessed at mRNA level using real-time PCR method. The characteristics of contractile activity were different between the pregnant and the nonpregnant myometrium. The amplitude of rhythmic contractions in the preterm and term myometrium was increased 2- to 2.5-fold when compared with that in the nonpregnant myometrium, but the frequency of rhythmic contractions was decreased by about half. LY333531 (10(-6) M) reduced the increased amplitude in the preterm and term myometrium by about 50%, and the inhibitory effects of LY333531 in the pregnant myometrium were significantly greater than that in the nonpregnant myometrium (about 50 vs 25%). However, the frequency in the pregnant and nonpregnant myometrium was not influenced by LY333531. Real-time PCR revealed a significant, five- to sevenfold increase in the expression of PKCbeta mRNA in the preterm and term myometrium when compared with the nonpregnant myometrium. These findings suggest that the increased amplitude of human myometrial contractions during pregnancy is related to the increased level of PKCbeta. A PKCbeta inhibitor may reduce preterm uterine contractions and prevent preterm delivery. 相似文献
54.
Isolation and characterization of poly(butylene succinate-co-butylene adipate)-degrading microorganism 总被引:1,自引:0,他引:1
Hayase N Yano H Kudoh E Tsutsumi C Ushio K Miyahara Y Tanaka S Nakagawa K 《Journal of Bioscience and Bioengineering》2004,97(2):131-133
Poly(butylene succinate-co-butylene adipate) (PBSA)-degrading bacterium, strain 1-A, was isolated from soil. Strain 1-A was identified as Bacillus pumilus on the basis of its physiological properties and partial 16S rRNA gene sequence. Strain 1-A also degraded poly(butylene succinate) (PBS) and poly(epsilon-caprolactone). On the other hand, poly(butylene adipate terephthalate) and poly(lactic acid) were minimally degraded by strain 1-A. The NMR spectra of degradation products from PBSA indicated that the adipate units were more rapidly degraded than 1,4-butanediol and succinate units. This seems to be one of the reasons why strain 1-A degraded PBSA faster than PBS. 相似文献
55.
Sho Shirakata Katsuhiko Ohkubo Yasuyuki Ishii Tokio Nakada 《Solar Energy Materials & Solar Cells》2009,93(6-7):988-992
Photoluminescence (PL) have been studied on Cu(In,Ga)Se2 (CIGS) thin films, CdS/CIGS and CIGS solar cells, to clarify the carrier recombination process. The chemical-bath deposition (CBD) of the CdS buffer layer on the CIGS thin film leads to (i) the enhancement of near-band-edge PL intensity by a factor of 2–3, (ii) change in energy of the defect-related PL and (iii) the slight change in the decay time. They are related not only to the minimization of the surface recombination but also to the modification of native defects at the Cu-poor surface of CIGS by the occupation of Cd atom at the Cu site. A donor–acceptor pair PL at low-temperature and temperature-dependent PL have been studied. They are discussed in terms of the impurity and defect levels created in the CIGS film during the CBD-CdS process. 相似文献
56.
Misao Kimura Hideki Hayashi Toshiyuki Kajihara Masakazu Kato Katsuhiko Kouchi 《Electrical Engineering in Japan》2008,165(4):11-20
Advanced energy storage systems have been widely applied to industries and are being installed at large buildings and factories to realize efficient energy usage. This paper presents a control method involving load frequency control and distribution network control (loss reduction control) using a part of customers' owned battery capacity. When 10% of total battery capacity of 100 MW in a network of 30‐GW generator capacities is used for load frequency control, a total of 1500‐MW generation units for load frequency control, at maximum, can be stopped without deterioration of power quality. In addition, when batteries are used for loss reduction in a distribution network, 2% of the loss on a summer day can be reduced. To realize both effects to their fullest, a novel integrated control algorithm is proposed and its economic effect is evaluated by numerical simulations. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 11–20, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20704 相似文献
57.
Harumi Yokokawa Natsuko Sakai Teruhisa Horita Katsuhiko Yamaji Yueping Xiong Takanori Otake Hiroo Yugami Tatsuya Kawada Junichiro Mizusaki 《Journal of Phase Equilibria》2001,22(3):331-338
Phase diagram calculations that were made previously for the ZrO2-MO m/2 (m = 2, 3, 4) systems and for the ZrO2-YO1.5-MO m/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic conductivity as a function of oxygen potential, and (3) a miscibility gap observed in air. The interaction parameters for the CeO2-CeO1.5-YO1.5 system were obtained from the reported oxygen nonstoichiometry in CeO2−x and rate earth doped ceria, (Ce,RE)O2−δ . The interaction parameters for the ZrO2-CeO2 subsystem were obtained so as to reproduce the observed miscibility gap at 1273 K. Those thermodynamic properties can reproduce consistently the experimental behaviors of the electronic conductivity and the TG results in the (Zr1−x Ce x )0.8Y0.2O1.9 solid solutions; these indicate the enhancement of reduction of CeO2. 相似文献
58.
Y Tanaka G Hosoi T Ishii T Shimoyama Y Fujimura M Sako 《Canadian Metallurgical Quarterly》1998,22(5):511-513
PURPOSE: To describe a case of Felty syndrome (FS) in a child with (JRA) and review the previous literature on this rare entity. METHODS: Review of clinical data including results of serial blood counts, bone marrow aspirate, human leukocyte antigen (HLA)-typing, and abdominal sonography. RESULTS: Serial blood counts over 2 years revealed persistent leukopenia and thrombocytopenia. Bone marrow aspirate showed normal trilineage hematopoiesis, abdominal sonography demonstrated an enlarged spleen, but normal liver and portal circulation. HLA-typing was most significant for positivity of the DR 1 allele. CONCLUSION: This is only the third child, and the first preadolescent, to be reported with FS complicating juvenile rheumatoid arthritis. This condition needs to be considered in the differential diagnosis when leukopenia, thrombocytopenia, or both develop in patients with JRA. 相似文献
59.
Effect of silver content on thermal fatigue life of Sn-xAg-0.5Cu flip-chip interconnects 总被引:5,自引:0,他引:5
Shinichi Terashima Yoshiharu Kariya Takuya Hosoi Masamoto Tanaka 《Journal of Electronic Materials》2003,32(12):1527-1533
The thermal fatigue properties of Sn-xAg-0.5Cu (x=1, 2, 3, and 4 in mass%) flip-chip interconnects were investigated to study
the effect of silver content on thermal fatigue endurance. The solder joints with lower silver context (x=1 and 2) had a greater
failure rate compared to those with higher silver content (x=3 and 4) in thermal fatigue testing. Cracks developed in the
solders near the solder/chip interface for all joints tested. This crack propagation may be mainly governed by the nature
of the solders themselves because the strain-concentrated area was similar for tested alloys independent of the silver content.
From the microstructural observation, the fracture was a mixed mode, transgranular and intergranular, independent of the silver
content. Higher silver content alloys (x=3 and 4) had finer Sn grains before thermal cycling according to the dispersion of
the Ag3Sn intermetallic compound, and even after the cycling, they suppressed microstructural coarsening, which degrades the fatigue
resistance. The fatigue endurance of the solder joints was strongly correlated to the silver content, and solder joints with
higher silver content had better fatigue resistance. 相似文献
60.
Arita K. Ito N. Hosoi N. Myamoto H. 《Semiconductor Manufacturing, IEEE Transactions on》2002,15(4):493-496
Developed a two-step copper (Cu) electroplating (EP) process using a seed-enhancement step with an alkali-metal-free Cu-pyrophosphate solution. The solution for the seed-enhancement step has low solubility of Cu compared with conventional Cu-sulfate solution and high macrothrowing power. As a result, the two-step EP solution provided a superior seed-enhancement effect and filling properties compared to conventional Cu sulfate EP. The seed-enhancement solution has excellent long-term stability of each component's concentration, and there is no change of process performance over a two-month period. The authors can easily control sheet resistance (Rs) of electroplated films which correlates with thickness and nonuniformity of seed-enhancement films with no maintenance other than the addition of de-ionized (DI) water to compensate for evaporated water. The two-step EP process achieved an excellent via-chain yield and a tight distribution of electromigration (EM) lifetime compared with the conventional EP process. Thus, the two-step EP process is a promising process for manufacturing technique of 0.1-/spl mu/m generation and beyond logic LSIs. 相似文献