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排序方式: 共有1595条查询结果,搜索用时 203 毫秒
1.
In a plant consisting of parallelized microreactors (MRs), the product quality is lowered because of a lack of flow uniformity among them when blockage occurs. It is not practical to install sensors in every MR from the viewpoint of cost when detecting the blocked MRs. In the previous study, the multiple blockage detection (MBD) method using a small number of sensors was proposed, but its performance became low when the number of sensors decreased. Here, the conventional algorithm for MBD is improved by considering the process behavior on blockage occurrence, and the effectiveness of the improved algorithm is demonstrated through a numerical case study. The effects of flow distributor types and sensor types on the MBD performance are numerically investigated. 相似文献
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3.
Asakawa K. Matake S. Hotta Y. Hiraoka T. 《Advanced Packaging, IEEE Transactions on》2006,29(2):211-217
A new type of a flexible printed circuit board with landless vias is developed using a novel method called interconnection via nanoporous structure (INPS). This method can make wires and vias of the printed circuit board simultaneously by a single photo-exposure process. A new photo-induced selective plating method was used to impregnate a nanoporous substrate with copper, and a new photomask was designed, which constitutes of a completely vacant large hole for via and aggregation patterns of very fine holes for wire. Because of the simple process, the INPS board is characterized by landless vias and very fine circuit. Owing to the structure, it is also characterized by flexibility and detachable wires. 相似文献
4.
T Murate K Yamashita H Ohashi Y Kagami K Tsushita T Kinoshita T Hotta H Saito S Yoshida KJ Mori 《Canadian Metallurgical Quarterly》1993,21(1):169-176
The erythroid-potentiating activity (EPA) of the tissue inhibitor of metalloproteinase-1 (TIMP-1) was re-examined using ELM-I-1-3, a mouse erythroleukemia cell line, which responded well to erythropoietin. Depletion of pre-existing TIMP-1 from fetal calf serum in culture medium using monoclonal antibody suppressed erythropoietin-induced differentiation as measured by the induction of hemoglobin, commitment assay and globin mRNAs. The removal of TIMP-1 also suppressed the proliferation of ELM-I-1-3 as measured by cell number and de novo DNA synthesis. These changes were reversed by the addition of purified TIMP-1 to the culture medium. Anti-TIMP-1 antibody also blocked both hexamethylene bisacetamide (HMBA)-induced erythroid differentiation and the proliferation of both ELM-I-1-3 and Friend erythroleukemia cells. Considering previous reports analyzing the chemical induction of Friend mouse erythroleukemia cell differentiation, our results suggest that erythropoietin- or HMBA-induced erythroid differentiation might also be coupled with cell proliferation. Our 3H thymidine-uptake experiment shows that TIMP-1 removal was also effective in the inhibition of cell growth of various other cell lines in addition to erythroleukemia cell lines. These results suggest that EPA action of TIMP-1 on erythroid leukemia cell lines is closely related to its activity to promote the cell growth of various cell lines and cells including erythroleukemia cell lines. 相似文献
5.
On an earthspace propagation path with the low elevation angle of 10 deg, the phase between co- and crosspolar signals occasionally showed rapid and irregular fluctuations during fine weather. These fluctuations were generally significant during the daytime, and were strongly in phase with the occurrence of the copolar amplitude scintillations. This could be attributed to the combined effects of the crosspolar phase pattern of the receiving antenna and small fluctuations of the angle of arrival of the radiowaves. 相似文献
6.
Shingo Hirano Akio Kawabata Masaru Yoshinaka Ken Hirota Osamu Yamaguchi 《Journal of the American Ceramic Society》1995,78(5):1414-1416
A compound denoted as (Ce0.75 Zr0.25 )O2 (Ce, ZrO8 ) is formed near room temperature from cerium and zirconium nitrates using hydrazine monohydrate. It has a cubic unit cell with a = 0.5342 nm. Characterization of powders heated to various temperatures at 10°C/min demonstrates that the specific surface area does not decrease below 20 mVg until >1000°C. 相似文献
7.
Masafumi Itoh Osamu Sakurada Minoru Hashiba Kouichi Hiramatsu Yukio Nurishi 《Journal of Materials Science》1996,31(12):3321-3324
An average shell volume occupied in the adsorption layer on alumina by a polyacrylic acid ammonium salts molecule (PAA) defined as the average area occupied by an adsorbed PAA on alumina multiplied by the average thickness of the water layer at the limit of thickening, has been calculated from the adsorbed amount of PAA and from the flow points of alumina in the presence of PAA of different molecular weights. A steric effect of the PAA dispersant on the dispersion of alumina resulted in a flow with no yield stress. This was due to the change of the extension of PAA in the adsorption shell from a sphere to an ellipsoid with a long axis which exceeded the effective distance that the van der Waals attraction force reaches at a molecular weight for the PAA of between 10 000–20 000. 相似文献
8.
Low-threshold, highly reliable 630 nm-band AlGaInP visible laser diodes have been developed by employing a low-loss optical waveguide buried in the AlInP layer. A low-threshold current of 19 mA at 25°C is obtained with a cavity length of 310 μm. This current is the lowest value for 630 nm-band AlGaInP visible laser diodes, to our knowledge. Our AlInP-buried laser diodes with a cavity length of 500 μm operated over 7000 h without significant degradation at 60°C and 5 mW 相似文献
9.
Toshimitsu Suzuki Osamu Yamada Yasuhiko Takahashi Yoshihisa Watanabe 《Fuel Processing Technology》1985,10(1):33-43
Hydroliquefaction of low-sulfur Australian coals (Wandoan and Yallourn) was studied using iron carbonyl complexes as catalyst. The addition of Fe(CO)5 (2.8 wt% Fe of coal) increased coal conversion from 48.6 to 85.2% for Wandoan coal, and from 36.7 to 69.7% for Yallourn coal in 1-methylnaphthalene at 425°C under an initial hydrogen pressure of 50 kg cm?2. When molecular sulfur was added to iron carbonyls (Fe(CO)5, Fe2(CO)9 and Fe3(CO)12), higher coal converions ( > 92%) and higher oil yields (>46%) were obtained, along with an increase in the amount of hydrogen transferred to coal from the gas phase (0.2 to 2.8%, d.a.f. coal basis). In the liquefaction studies using a hydrogen donor solvent, tetralin, Fe(CO)5S catalyst increased the amount of hydrogen absorbed from the gaseous phase and decreased the amount of naphthalene dehydrogenated from tetralin. The direct hydrogen transfer reaction from molecular hydrogen to coal fragment radicals seems to be a major reaction pathway. Organic sulfur compounds, dimethyldisulfide and benzothiophene, and inorganic FeS2 and NiS were found to be good sulfur sources to Fe(CO)5. From X-ray diffraction analyses of liquefaction residues, it is concluded that Fe(CO)5 was converted into pyrrhotite (Fe1?xS) when sulfur was present, but into Fe3O4 in the absence of sulfur. 相似文献
10.
K Toyama K Ohyashiki Y Yoshida T Abe S Asano H Hirai K Hirashima T Hotta A Kuramoto S Kuriya 《Canadian Metallurgical Quarterly》1993,7(4):499-508
It is well known that cytogenetic analysis in patients with myelodysplastic syndrome (MDS) provides information useful in determining their prognosis. Based on the chromosomal results obtained from 401 MDS patients by a multicentric study in Japan, we studied correlations between chromosomal findings and prognosis or leukemic transformation in MDS patients. Patients with complex aberrations (cytogenetic abnormalities at more than three chromosomes), of any subtype, had a poor prognosis; for example, > 60% of patients with refractory anemia (RA) showing complex aberrations died within one year, but only 11% of them developed leukemia. In patients with RA with ringed sideroblasts (RARS), > 70% of those with complex aberrations evolved into the leukemic phase and survived for less than one year, suggesting a biologic heterogeneity in RARS patients. By contrast, about 5% of patients with RA or RARS exhibiting chromosomal findings other than -7/7q-, +8, two aberrations, and complex aberrations, developed leukemia and had a favorable prognosis. Therefore, the presence of chromosome abnormalities alone in patients with RA or RARS is not a factor in predicting leukemic transformation or poor prognosis. In patients with refractory anemia with an excess of blasts (RAEB), the presence of chromosome aberrations at MDS diagnosis affected the occurrence of leukemic transformation (24% versus 43%), however, no particular difference was noted in patients with RAEB in transformation with regard to whether they had chromosome changes or not, and about 60% of them evolved into leukemia. The poor prognosis related to complex aberrations was consistently noted in all MDS subtypes or age-matched groups, indicating that this cytogenetic anomaly is an independent risk factor for a poor prognosis in MDS patients. The duration between MDS diagnosis and development of the leukemic phase and that between the latter and death were significantly shorter in patients with complex aberrations than those without this change. Although the clinical significance of certain chromosomal abnormalities differs among subtypes of MDS, a new scoring system for predicting prognosis by cytogenetic changes, in combination with hematologic parameters, was proposed. 相似文献