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721.
The chelating membranes for adsorption of metal ions were prepared by the photografting of glycidyl methacrylate (GMA) onto a polyethylene (PE) film and the subsequent modification of the resultant GMA‐grafted PE (PE‐g‐PGMA) films with disodium iminodiacetate in an aqueous solution of 55% DMSO at 80°C. The adsorption and desorption properties of the iminodiacetate (IDA) group‐appended PE‐g‐PGMA (IDA‐(PE‐g‐PGMA)) films to Cu2+ ions were investigated as functions of the grafted amount, pH value, Cu2+ ion concentration, and temperature. The amount of adsorbed Cu2+ ions increased with an increase in the pH value in the range of 1.0–5.0. The time required to reach the equilibrium adsorption decreased with an increase in the temperature, although the degree of adsorption stayed almost constant. The amount of Cu2+ ions desorbed from the (IDA‐(PE‐g‐PGMA)) films increased and the time required to reach the equilibrium desorption decreased with an increase in the HCl concentration. About 100% of Cu2+ ions were desorbed in the aqueous HCl solutions of more than 0.5M. The amounts of adsorbed and desorbed Cu2+ ions were almost the same in each cyclic process of adsorption in a CuCl2 buffer at pH 5.0 and desorption in an aqueous 1.0M HCl solution. These results indicate that the IDA‐(PE‐g‐PGMA) films can be applied to a repeatedly generative chelating membrane for adsorption and desorption of metal ions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99:1895–1902, 2006 相似文献
722.
Feeding rats beans with resistant starch reduces their serum cholesterol concentration; however, the mechanism by which this
occurs is not fully understood. We examined the effects of enzyme-resistant fractions of adzuki (Vigna angularis) and tebou (Phaseolus vulgaris, var.) beans on serum cholesterol and hepatic mRNA in rats. Rats were fed a cholesterol-free diet with 50 g of cellulose
powder (CP)/kg, 50 g of an enzyme-resistant fraction of adzuki starch (AS)/kg, or 50 g of an enzyme-resistant fraction of
tebou starch (TS)/kg diet for 4 wk. There were no significant differences in body weight, liver weight, and cecum contents
among the groups, nor was there a significant difference in food intake among the groups. The levels of serum total cholesterol,
VLDL + intermediate density lipoprotein + LDL-cholesterol, and HDL cholesterol in the AS and TS groups were significantly
(P<0.05) lower than in the CP group throughout the feeding period. Total hepatic cholesterol in the CP group was significantly
(P<0.05) lower than in the AS and TS groups, fecal cholesterol excretion in the TS group was significantly (P<0.05) greater than in the CP and AS groups, and the fecal total bile acid concentrations in the AS and TS groups were significantly
(P<0.05) higher than in the CP group. Cecal acetate, propionate, and n-butyrate concentrations in the AS and TS groups were significantly (P<0.05) higher than in the CP group. The level of hepatic scavenger receptor class B1 (SR-B1) mRNA in the TS group was significantly
(P<0.05) higher than in the CP group, and the levels of hepatic cholesterol 7α-hydroxylase mRNA in the AS and TS groups were
significantly (P<0.05) higher than in the CP group. These results suggest that AS and TS have a serum cholesterol-lowering function due to
the enhanced levels of hepatic SR-B1 and cholesterol 7α-hydroxylase mRNA. 相似文献
723.
Hiroyuki Oguma Isamu Morino Hiroshi Suto Yukio Yoshida Nawo Eguchi Akihiko Kuze 《International journal of remote sensing》2013,34(24):9033-9049
This article describes the results of a field experiment performed to confirm the feasibility of measuring the solar spectra absorbed by carbon dioxide (CO2) using a short wavelength infrared Fourier transform spectrometer (SWIR-FTS) installed onboard an airship. These airship-borne observations, conducted on 7 April 2005, represent the first aircraft-borne spectroscopic experiment on greenhouse gases (GHGs) in Japan and were performed as part of the Greenhouse Gases Observing Satellite (GOSAT) project. To develop and demonstrate an effective retrieval algorithm to derive CO2 column amounts from spectroscopic observations, ground-surface scattered solar absorption spectra were observed by SWIR-FTS installed onboard the airship. This instrument is a breadboard model (BBM) of the Thermal and Near-infrared Sensor for Carbon Observation (TANSO) of GOSAT, which was successfully launched on 23 January 2009. The spectra of CO2 observed using the BBM were compared with the simulated spectra calculated by a radiative transfer code based on airship-borne in situ measurement data, which were obtained at the time of FTS measurements. The two sets of spectra are in agreement within 5%, and we identified solutions to several technical problems related to the FTS instrument, thereby improving the signal-to-noise ratio (SNR). 相似文献
724.
The interest about recovery of used products and materials have been increased. Therefore, reverse logistics network problem (rLNP) will be powerful and get a great potential for winning consumers in a more competitive context in the future.We formulate a mathematical model of remanufacturing system as three-stage logistics network model for minimizing the total of costs to reverse logistics shipping cost and fixed opening cost of the disassembly centers and processing centers. And we consider a multi-stage, multi-product and some attach condition for disassembly centers and processing centers, respectively.For solving this problem, we propose a genetic algorithm (GA) with priority-based encoding method consisting of 1st and 2nd stages combined a new crossover operator called as weight mapping crossover (WMX). A heuristic approach is applied in the 3rd stage to transportation of parts from processing center to manufacturer. Numerical experiments with various scales of rLNP models show the effectiveness and efficiency of our approach by comparing the recent researches. 相似文献
725.
The vision for surveillance is an important task in many computer vision applications. The monitoring system concerns the tracking and recognition of people, and more generally, the understanding of human behaviors, from image sequences involving humans. Several methods for human tracking and human behavior recognition have been proposed by various researchers. But most of those do not have versatility and flexibility. In this paper, we propose an efficient and robust object tracking algorithm which use the color features, the distance features and count feature based on an evolutionary techniques to measure the observation similarity. And then we will track each person and classify their behavior properties by analyzing their trajectory pattern. We propose multi-layer perceptron based on hybrid genetic algorithm using Gaussian synapse make the recognition algorithm very efficient and robust for classify human behavior by trajectory pattern. 相似文献
726.
Silicon oxynitride films have been grown with thermally excited N2O gas, which has a low toxicity in comparison with other oxynitridation agents. Dependences of reaction rates on excitation temperature and substrate temperature have been investigated by Auger electron and photoelectron spectroscopies. These results show that the thermal excitation of N2O obviously promotes the oxynitridation of the silicon surface, especially the oxidation reaction. At higher substrate temperatures, the nitridation of the silicon surface increases and the oxidation is reduced. By mass analysis of the residual gas in the reaction chamber, it was also found that the thermal excitation of N2O causes N2O to be decomposed into N2 and O. This is consistent with the obtained effect that the thermal excitation of N2O promotes especially the oxidation reaction, because atomic oxygen (O) acts as a strong oxidant. 相似文献
727.
A genetic algorithm with modified crossover operator and search area adaptation for the job-shop scheduling problem 总被引:11,自引:0,他引:11
The genetic algorithm with search area adaptation (GSA) has a capacity for adapting to the structure of solution space and controlling the tradeoff balance between global and local searches, even if we do not adjust the parameters of the genetic algorithm (GA), such as crossover and/or mutation rates. But, GSA needs the crossover operator that has ability for characteristic inheritance ratio control. In this paper, we propose the modified genetic algorithm with search area adaptation (mGSA) for solving the Job-shop scheduling problem (JSP). Unlike GSA, our proposed method does not need such a crossover operator. To show the effectiveness of the proposed method, we conduct numerical experiments by using two benchmark problems. It is shown that this method has better performance than existing GAs. 相似文献
728.
To examine the polar effect on spin trapping with 2,4,6-tri-tert-butyl-1-nitrosobenzene (BNB), propagating radicals from monomers were allowed to react with BNB to provide anilino radicals and nitroxides of which the amounts were determined by ESR spectroscopy. The proportion of the anilino radical increased with an increase in the steric congestion and electron donating character of the radical. Poly(vinyl ether) radicals exclusively gave the respective anilino radicals. Poly(vinyl ester) radicals yielded large amounts (>50%) of the anilino radicals, although the nitroxides were the main products (>85%) from the poly(alkyl acrylate) radicals. The polymer radicals of methyl methacrylate and ethyl itaconate only yielded the anilino radicals. The polymer radicals from ethyl -chloroacrylate and acrylonitrile reacted preferentially with the respective monomers leading to polymer formation, and the ESR spectra of the adducts were not observed. 相似文献
729.
The rehabilitation inpatients in hospitals often complain about the service quality due to the long waiting time between the therapeutic processes. To enhance service quality, this study aims to propose an intelligent solution to reduce the waiting time through solving the rehabilitation scheduling problem. In particular, a bi-objective genetic algorithm is developed for rehabilitation scheduling via minimizing the total waiting time and the makespan. The conjunctive therapy concept is employed to preserve the partial precedence constraints between the therapies and thus the present rehabilitation scheduling problem can be formulated as an open shop scheduling problem, in which a special decoding algorithm is designed. We conducted an empirical study based on real data collected in a general hospital for validation. The proposed approach considered both the hospital operational efficiency and the patient centralized service needs. The results have shown that the waiting time of each inpatient can be reduced significantly and thus demonstrated the practical viability of the proposed bi-objective heuristic genetic algorithm. 相似文献
730.
Effect of addition of salt on the viscometric behavior of the dilute or concentrated aqueous solution of hydroxypropyl cellulose (HPC) was determined by means of an Ubbelohde or a cone-plate viscometer. That effect on the turbidity of the dilute system was also determined. As salts, NaCl, LiCl, and thiourea were chosen. The turbidity and viscometric behavior for the dilute system, and the viscometric behavior for the concentrated system were greatly affected by salt type and concentration. With increasing NaCl or LiCl concentration, the cloud point decreased, [η] showed a maximum, Huggins' constant k′ showed a minimum, and the shear viscosity for concentrated isotropic solutions showed a maximum. The 45 wt % solution with no salt showed a viscometric behavior which was characteristic of lyotropic liquid crystals; however, with increasing NaCl concentration, a critical temperature at which the shear viscosity showed a maximum with respect to temperature shifted to lower temperature. This behavior was due to an increase in the turbidity, not due to a phase transformation. On the other hand, an addition of thiourea did not affect so greatly the turbidity and viscometric behavior as an addition of NaCl or LiCl did. We speculated different actions of NaCl and thiourea. 相似文献