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11.
Reuse of wastewater is regarded as one important way to deal with the world's shortage of potable water. The authors focused on a disinfection system using micro-bubbles and evaluated its capability for wastewater reuse. This paper reports experimental results from examination of the basic characteristics of micro-bubbles and disinfection of secondary effluent by air or ozone micro-bubbles. The results suggest that when micro-bubbles are applied in an ozonation system it is possible to reduce the reactor size, the amount of ozone decomposition equipment needed and the ozone dose rate.  相似文献   
12.
Local orientations of superconducting YBa2Cu3O x (123) and embedded Y2BaCuO5 (211) particles within bulk, melt-textured 123 samples are studied on a local scale by means of electron backscatter diffraction (EBSD). The embedded Y2BaCuO5 (211) particles do not show any preferred texture, but their presence within the 123-matrix alters the growth of the 123-phase, independent of the orientation. EBSD enables to analyse the interactions between the 123- and 211-phases in detail.  相似文献   
13.
In accord with the increasing concern about the global environmental issues, the absorption refrigeration heat-pump systems are currently being considered very promising and attractive. For the purpose of supporting the advanced R&D technology in this area, we have developed a novel correlation to represent the bubble-point pressures of LiBr H2O solutions. The developed correlation covers the most extensive range of validity ever proposed: 273–483 K for temperatures, 0.05 kPa to 1.0 MPa for pressures. and 29 76 wt% LiBr for concentrations.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994. Boulder, Colorado, U.S.A.  相似文献   
14.
It has recently been reported that there exists a new 'RING-finger' protein family among the zinc-finger (Zf) proteins. Previously, we had isolated the mouse Mel-18 cDNA (mMel-18) encoding the nuclear RING-finger protein that exhibits an ability to bind to a nonspecific DNA column. Here, we have isolated and characterized the human Mel-18 cDNA (hMel-18) using the mMel-18 cDNA as a probe. The deduced hMel-18 protein contains 344 amino acids (38 kDa) with a RING-finger motif, a helix-loop-helix (HLH)-like structure and a Pro/Ser-rich region. The hMel-18 gene is conserved among vertebrates. Its mRNA is highly expressed in placenta, lung and kidney, but the level is low in liver, pancreas and skeletal muscle. Using in situ hybridization, we mapped hMel-18 to band q22 of chromosome 12. It is possible that the Mel-18/bmi-1 gene family represents a mammalian homologue of the Drosophila polycomb gene group.  相似文献   
15.
In order to evaluate the significance of repeat transurethral resection (TUR) in differentiating stage A1 prostatic adenocarcinoma from those with stage A2, we performed repeat TUR in 34 patients with an initial diagnosis of stage A1 prostatic adenocarcinoma. It was found that residual adenocarcinoma was present in five cases (14.7%), but the diagnosis was changed from stage A1 to stage A2 in only one case (2.9%). In one patient with final diagnosis of stage A1 carcinoma, bone metastases were detected seven months after the repeat TUR. It was concluded that repeat TUR for stage A1 prostatic adenocarcinoma did not yield clinically significant information.  相似文献   
16.
Schottky barrier heights (SBHs) of a variety of metals (In, Cd, Nb, Ti, W, Cu, Ag, Au, Ni, Pt, and Se) contacting to p-ZnSe grown by a molecular beam epitaxy method were determined by analyzing capacitance-voltage (C-V) and/or current density-voltage (J-V) curves. The SBH values of the Au and Ni contacts were determined from intersections of straight lines of the C−2-V curves to be 1.23 and 1.13 eV, respectively. The J-V calculations provided a large SBH value of 1.2 ± 0.1 eV for a variety of metals, indicating that the Fermi-level could be pinned at the contact interface. Reduction of the SBH values to a level lower than 0.4 eV and/or increase of doping concentrations to a level higher than 1020 cm−3 are essential to obtain an ohmic contact with contact resistivity of around 10−3 Ω·cm2.  相似文献   
17.
18.
By employing a single thick molybdenum fibre-copper matrix composite with very weak interfacial bonding, it was confirmed that flow stress, internal stress, effective stress and change in flow stress due to change in strain rate of the composite obey the simple rule of mixtures; strain-hardening exponent, stress exponent of strain rate, effective stress exponent of dislocation velocity and activation volume obey the modified rule of mixtures in the whole range of plastic deformation of the composite. This means that the inherent features of the fibre in the present composite were conserved beyond the failure strain of the fibre tested alone, and the above deformation parameters of the composite were, to a first approximation, determined by the inherent parameters of the fibre and the matrix.  相似文献   
19.
Since the natural estrogens 17 beta-estradiol (E2) and estron (E1), and the synthetic estrogen 17 alpha-ethynyl estradiol (EE2) have strong endocrine disrupting effects and the tendency to persist in effluent from wastewater treatment plants, effective measures are needed to remove them from wastewater. In this research, to gain an understanding of the characteristics of estrogen decomposition by ozonation, experiments were conducted using effluent from an actual wastewater treatment plant. In this experiment, estrogen was added to effluent at a concentration of 200 ng/l and 20 ng/l before the ozonation experiments. The results showed 90% or more of estrogen concentration and estrogenic activity of E2, El and EE2 to be removed at an ozone dose of 1 mg/l. At an ozone dose of 3 mg/l, the estrogen concentration and estrogenic activity of E2, El and EE2 in the treated water fell below the detection limit. The removal rate was not influenced by the kind of estrogen. No generation of byproducts with estrogenic activity was observed. The authors conclude that estrogen in secondary treated wastewater can be almost entirely removed at the practical ozone dose rate applied for the purpose of disinfection, which is up to about 5 mg/l.  相似文献   
20.
The effects of leukotrienes C4 and D4 on ciliary activity of human paranasal sinus mucosa were investigated in vitro. Normal mucosa was surgically obtained from human paranasal sinuses and incubated in the form of tissue culture. Ciliated cells were magnified under an inverted microscope, and ciliary activity was photoelectrically measured. LTD4 progressively inhibited ciliary activity, and showed a more potent effect on ciliary activity compared to LTC4. The concentrations of LTC4 and LTD4 in the incubation medium were determined by radioimmunoassay when the mucosa was incubated with 10(-8) M LTC4. The concentration of LTD4 gradually increased and after 90 min reached the maximum of 0.71 x 10(-8) M, while that of LTC4 was reduced to about 10% of its initial concentration within 60 min. These results suggested the possible conversion of LTC4 to LTD4 on the mucosa, and that LTC4 can inhibit ciliary activity by means of LTD4.  相似文献   
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