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991.
Kawanishi M Takamura-Enya T Ermawati R Shimohara C Sakamoto M Matsukawa K Matsuda T Murahashi T Matsui S Wakabayashi K Watanabe T Tashiro HY Yagi T 《Environmental science & technology》2004,38(23):6424-6429
The estrogenic activity in water at various localities on Lake Biwa-Yodo River, a representative watershed in Japan, was measured using a recombinant yeast that expresses the human estrogen receptor. The yeast bioassay revealed that the activities of 13 water samples had an average value of 14 pmol/L (3.8 ng/L) (17beta-estradiol equivalent) with a very wide range from 0 to 72 pmol/L (0-19.6 ng/ L), and two of the samples had prominent levels of activity (72 pmol/L (19.6 ng/L) and 56 pmol/L (15.2 ng/L)). We analyzed these two samples with instrumental approaches. A high-performance liquid chromatogram profile showed that the strong activity in one sample, which was collected just downstream of a sewage-treatment plant, would be due to 17beta-estradiol and estrone, whose source is considered to be human urine contained in the effluent of the plant. The activity in the other sample, which was obtained from a tributary river in a primarily residential area with some industrial development (i.e., Osaka City), however, did not correspond to 17beta-estradiol, estrone, or synthetic chemicals known as estrogenic. Analysis of a fraction with estrogenic activity by liquid chromatography-mass spectrometry (LC-MS) provided evidence that the activity in the water sample resulted from the presence of genistein, an isoflavone compound of plant origin. 相似文献
992.
120 nm period gratings were fabricated by a novel method using ECR-CVD SiNx films. SiNx films deposited on photoresist have a higher etching rate than that on the flat semiconductor substrate. Good use of this difference was made to fabricate gratings whose period is one-half that of the original, formed by a holographic exposure technique 相似文献
993.
Effects of chlorine on the decrease of estrogenic chemicals 总被引:4,自引:0,他引:4
The effects of chlorination on the elimination of three estrogenic chemicals such as 17beta-estradiol, nonylphenol and bis-phenol A were investigated using yeast two-hybrid assay (YTA), estrogen receptor (ER) competition assay (ER-CA), and high-performance liquid chromatography/mass spectrometry (LC/MS). The results of YTA, ER-CA and the analysis of LC/MS indicated that the estrogenic activity of the above-mentioned three endocrine disruptors were significantly reduced as a result of chlorination. The decrease in estrogenic activity paralleled a decrease in estrogenic chemicals under the influence of free chlorine. One common characteristic of estrogenic chemicals is the presence of a phenolic ring. Considering that a phenolic ring is likely to undergo some sort of transformation in an aqueous chlorination solution, the above-mentioned results may be applied to the rest of the estrogenic chemicals in natural waters. 相似文献
994.
Medium temperature carbon dioxide gas turbine reactor 总被引:1,自引:0,他引:1
A carbon dioxide (CO2) gas turbine reactor with a partial pre-cooling cycle attains comparable cycle efficiencies of 45.8% at medium temperature of 650 °C and pressure of 7 MPa with a typical helium (He) gas turbine reactor of GT-MHR (47.7%) at high temperature of 850 °C. This higher efficiency is ascribed to: reduced compression work around the critical point of CO2; and consideration of variation in CO2 specific heat at constant pressure, Cp, with pressure and temperature into cycle configuration. Lowering temperature to 650 °C provides flexibility in choosing materials and eases maintenance through the lower diffusion leak rate of fission products from coated particle fuel by about two orders of magnitude. At medium temperature of 650 °C, less expensive corrosion resistant materials such as type 316 stainless steel are applicable and their performance in CO2 have been proven during extensive operation in AGRs. In the previous study, the CO2 cycle gas turbomachinery weight was estimated to be about one-fifth compared with He cycles. The proposed medium temperature CO2 gas turbine reactor is expected to be an alternative solution to current high-temperature He gas turbine reactors. 相似文献
995.
In this research, a computational model that simulates the mental function of multicolor aesthetic evaluation through backpropagation neural networks was constructed. Helmut Leder's psychological model served as the theoretical framework. We determined the macro‐architecture of the computational model through two psychological experiments using the semantic differential (SD) method. The aesthetic score of a multicolor stimulus is defined as the inverse of its factor score on the factor “Pleasure” extracted in the first experiment, and each of the three factors extracted in the second experiment—i.e., “Stability,” “Heaviness,” and “Presence”—is regarded as a simple perceptual feature. The genetic algorithm was then employed to optimize the hidden layer node number, the learning rate, and the momentum constant of each neural network. In two simulation tests, this computational model exhibited some predictive power, implying that the model can be regarded as a relatively successful approximation of the psychological mechanism of multicolor aesthetic evaluation. In addition, the results of the second simulation also show that the perceptual feature “Heaviness” possesses the principal impact on the aesthetic evaluation of multicolor objects, whereas the other two perceptual features “Stability” and “Presence” have a minor influence. The heavier and/or more stable a multicolor object is perceived to be, the less aesthetically pleasing it is. Conversely, the stronger the sense of matter presence a multicolor object elicits, the more aesthetically appealing it is. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 216–235, 2017 相似文献
996.
Makoto Toba Yasuo Miki Takashi Matsui Masaru Harada Yuji Yoshimura 《Applied catalysis. B, Environmental》2007,70(1-4):542-547
To achieve selective hydrodesulfurization (HDS) of fluid catalytic-cracked (FCC) gasoline for producing sulfur-free gasoline (S < 10 ppm), the reactivity of various olefins contained in FCC gasoline on CoMoP/Al2O3 sulfide catalysts was investigated. Isomerization of the CC double bond from the terminal position to an internal position was observed. The steric hindrance around the CC double bond suppresses the reactivity of olefin hydrogenation. The sulfidation temperature of the catalyst has a major influence on olefin hydrogenation active sites. Addition of the appropriate amount of cobalt (Co/Mo ratio approximately 0.6) contributes to the suppression of olefin hydrogenation at high reaction temperature (260 °C). From the comparison of catalytic performance and characterization of our CoMoP/Al2O3 catalyst with an analogous commercial catalyst, it is suggested that the hydrogenation of olefins depends not only on the state of the Mo CUS but also on the steric effects of both olefin structure and MoS2 crystalline structure. 相似文献
997.
This paper presents a simple nonlinear magnetic analysis for a surface-mounted permanent-magnet synchronous motor as an assistant design tool of finite-element analysis (FEA). The equivalent magnetic circuit of the motor used in the proposed analysis is composed of the saturable permeance tips in the stator teeth for considering the local magnetic saturation. As a result, the proposed analysis is capable of calculating the flux distribution and the torque characteristics in the presence of magnetic saturation. The effectiveness of the proposed analysis is verified by comparing with three-dimensional (3-D) FEA in terms of the analytical accuracy. The computation time is greatly reduced as short as 1.5 s while the 3-D FEA requires as much as 32 min for the same evaluation. 相似文献
998.
The co‐helicity merging operations of compact toroid (CT) and spherical tokamak (ST) have been performed with external toroidal fields in the CT/ST merging device TS‐4. The low‐q (safety factor) CT merging as the compact RFP merging and the spheromak merging show the flux conversion from toroidal to poloidal in the course of the reconstruction of the Taylor force free state. The relaxation to the Taylor state proceeds through the following three states: (1) axisymmetric merging with increasing toroidal flux; (2) increase in the poloidal flux Ψ; and (3) relaxation to the Taylor state. The high‐q ST merging shows different relaxation process from those of the compact RFP and the spheromak mergings. Increases in Ψ were not clearly observed in the ST merging. The measured eigenvalues λ show that ST's, especially high‐q ST's, approach a unique intrinsic equilibrium state that has a λ proportional to Ψ with a longer lifetime than that of CT's. When external toroidal field is set in a certain range between the low‐q operation and the high‐q operation for ST's, an abnormal phenomenon was found in the ST formation, namely, a drastic decrease in the plasma lifetime. This phenomenon is characterized by very weak poloidal flux generations during the initial plasma production phase and the subsequent plasma separation phase when the plasma starts detaching from the flux core. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(4): 7–15, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20069 相似文献
999.
Plasma-polymerized hexafluoropropene (PPHFP) film had adhesive strength that was low enough for use as a release coating, but a small amount of PPHFP peeled off from a poly(ethylene terephthalate) (PET) film substrate. The insertion of a soft and elastic polymer, polyethylene glycol, between the two layers prevented the PPHFP peeling off from PET. The results also showed that the polymerization degree of PPHFP was low. 相似文献
1000.
Maekawa Takuya Yanagisawa Yutaka Kishino Yasue Kamei Koji Sakurai Yasushi Okadome Takeshi 《Pervasive Computing, IEEE》2008,7(4):20-27
The Object-Blog service application automatically converts raw sensor data to environment-generated content (EGC), including texts, graphs, and figures. This conversion facilitates data searching and browsing. Generated content can serve several purposes, including memory aids, security, and communication media. In Object-Blog, personified objects automatically post entries to a weblog about sensor data obtained from sensors attached to the objects. Feedback thus far from participants working with Object-Blog in an experimental environment has been positive. 相似文献