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11.
The precipitation of droplets was directly observed on a BaO–B2O3 melt in a drop shaft experiment. This is the first time that precipitation of droplets has been observed in a 4.5 s drop test. The melt film of 4BaOz96B2O3 (mol%) held on a platinum wire loop was heated above the critical tem-perature to produce uniformity and was cooled down to the phase separation temperature range. Phase separation of the melt was observed directly with a video camera. The IR image of the melt was simultaneously detected with a CCD array and was converted into a two-dimensional thermograph.  相似文献   
12.
Crosslinked poly(N-benzyl-4-vinyipyridinium bromide) has been found to be digested by activated sludge obtained from sewage works. As an extension of this work, the authors attempted to make poly(methyl methacrylate) biodegradable by incorporation of a pyridinium group. Poly(methyl methacrylate) containing a small amount of N-benzyl-4-vinylpyridinium chloride in the main chain showed remarkable reduction in molecular weight and gravimetric weight when placed in an aeration tank of a sewage works. Molecular weight reduction by activated sludge was more conspicuous when content of the pyridinium group was larger and the original molecular weight before the biological treatment was lower. Since insoluble pyridinium-type polymer captures microbial cells alive, this biodegradation appears to be facilitated by enhancement of affinity of the synthetic hydrophobic polymer with cells of microogranisms. © 1994 John Wiley & Sons, Inc.  相似文献   
13.
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three.  相似文献   
14.
Barium titanate ultrafine particles were synthesized from amorphous titania by a hydrothermal method. The mean size of the barium titanate particles prepared at a hydrothermal treatment time of 4 h, was nearly equal to 0.04 5 m in the range of barium-to-titanium molar ratio (BT) 2, and approximately agreed well with the crystallite size. At a BT molar ratio of 1.0, the mean particle size increased to 0.2 m, while the crystallite size remained constant at 0.045 m. When the particle size ranged from 0.12–0.20 m, prepared for the BT molar ratio of 1.0–1.4, the specific dielectric constant for a sintered disc composed of these particles attained a value of 5000 or more. As the BT molar ratio increased to exceed 1.5, when the mean particle size decreased from 0.13 m to 0.045 m, the specific dielectric constant for the sintered disc was decreased greatly. The specific dielectric constant for the sintered disc can be correlated well with the size of the composing particles.  相似文献   
15.
We developed a method to improve the quantitative precision of FDG-PET scans in cancer patients. The total-lesion evaluation method generates a correlation coefficient (r) constrained Patlak parametric image of the lesion together with three calculated glucose metabolic indices: (a) the total-lesion metabolic index ("KT-tle", ml/min/lesion); (b) the total-lesion voxel index ("VT-tle", voxels/lesion); and (c) the global average metabolic index ("KV-tle", ml/min/voxel). METHODS: The glucose metabolic indices obtained from conventional region of interest (ROI) and multiplane evaluation were used as standards to evaluate the accuracy of the total-lesion evaluation method. Computer simulations and four patients with metastatic melanoma before and after chemotherapy were studied. RESULTS: Computer simulations showed that the total-lesion evaluation method has improved precision (% s.d. < 0.6%) and accuracy (approximately 10% error) compared with the conventional ROI method (% s.d. approximately 5%; approximately 25% error). The KT-tle and VT-tle indices from human FDG-PET studies using the total-lesion evaluation method showed excellent correlations with the corresponding values obtained from the conventional ROI methods and multiplane evaluation (r approximately 1.0) and CT lesion volume measurements. CONCLUSION: This method is a simple but reliable way to quantitatively monitor tumor FDG uptake. The method has several advantages over the conventional ROI method: (a) less sensitive to the ROI definition, (b) no need for image registration of serial scan data and (c) includes tumor volume changes in the global tumor metabolism.  相似文献   
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Since cash flow of asset in the long run is generally subject to economic fluctuation, and also to potential damage due to seismic hazard risk, asset pricing is more relevantly evaluated, provided that uncertainties of both cash flow and seismic risk are properly taken into account. This study will propose a discounted cash flow method to evaluate asset pricing, in which incomes gained from asset are modeled as a Markov process and seismic loss is modeled due to only one earthquake event during the service time. A numerical example is demonstrated for an 11 story steel reinforced commercial building considering the service time of 50 years. Various risk–asset price curves are numerically obtained in the form of probability of excess versus asset price with discount rate as a parameter for cases with and without earthquake loss taken into account, and for a case in which earthquake strengthening measure is implemented. These curves contribute information to decision makers in charge of risk and investment management.  相似文献   
18.
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.  相似文献   
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It has been reported that an anisotropic magnetic field could produce the three-dimensional alignment of fine single-crystal particles with the orthorhombic crystal structure.However,the three-dimensional alignment was achieved only in suspensions.Fabrication of bulk"single"materials that have the three-dimensional alignment of grains has been desired.This study proposes a procedure for the fabrication,which consists of slip casting under an oscillating magnetic field and sintering.Optimization of casting and sintering conditions achieved the three-dimensionally aligned bulkβ-FeSi2.  相似文献   
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