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1.
The grafting of acrylic acid onto electron beam‐irradiated polypropylene was carried out using preirradiation method. The stability of peroxy radicals was investigated by electron spin resonance. It was found that the decay of peroxy radicals is much faster at 70°C than at 40°C and ambient temperature. The grafting has been observed to be strongly dependent on the monomer dilution in the reaction medium. The grafting was ascertained by attenuated total reflectance (ATR). The distribution of grafts across the samples was monitored by infrared microscopy. It was found that the graft management is considerably influenced by composition of the grafting medium. The grafting involving pure monomer leads to the surface enrichment with the polyacrylic acid chains. The samples grafted in pure monomer led to much lower contact angles as compared to the diluted monomer solution. The swelling of the grafted samples also showed a trend that was governed by the graft management. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 546–553, 2006 相似文献
2.
Polarised attenuated total reflection FTIR spectroscopy has been used for detailed orientation mapping of 2l polyethylene terephthalate bottles subjected to different preform heating times. The results for the bottle with the standard preform heating time reveal significant surface orientation variations along the bottle hoop and length directions, with the inner bottle surface also showing consistently greater chain orientation in the hoop direction than found for the outer surface. Decreasing the preform heating time has less effect on the chain orientation than increasing the heating time, with the latter causing reduced chain orientation in the final bottle. The absorbance of the 1340 cm−1 band provides a quick and reliable indication of these chain orientation trends. In contrast, the extent of benzene ring orientation parallel to the bottle surface showed little variation and remained consistently high at the majority of the surface bottle positions probed. 相似文献
3.
C.?M.?SeubertEmail author M.?E.?Nichols A.?V.?Kucherov 《Journal of Coatings Technology and Research》2005,2(7):529-538
The long-term weathering performance of two UV-curable clearcoat systems was studied using in-plane microtomy in combination
with infrared spectroscopy, UV spectroscopy, and ESR spectroscopy. Oxygen transport characteristics were also studied using
the half-time method. The photooxidation versus depth profile was highly dependant on the presence of hindered amine light
stabilizers (HALS) for both coating systems. Ultraviolet light absorbers (UVA) had little effect on the photooxidation profile.
A photooxidation gradient was formed in both clearcoats due to a reduction in oxygen solubility when compared to standard
thermoset clearcoats. This gradient was only seen in formulations not containing HALS.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago,
IL. 相似文献
4.
Aziz Rezig Tinh Nguyen David Martin Lipiin Sung Xiaohong Gu Joan Jasmin Jonathan W. Martin 《Journal of Coatings Technology and Research》2006,3(3):173-184
The relationship between chemical degradation and thickness loss of an unpigmented, non UV-stabilized, crosslinked amine-cured
epoxy coating exposed to three UV conditions was investigated. Spin-coated samples having a thickness of approximately 7 μm
on an Si substrate were prepared from a stochiometric mixture of a bisphenol A epoxy resin and a tetra-functional amine curing
agent. Samples were exposed outdoors and to two accelerated laboratory UV environments. Chemical degradation and thickness
loss were measured by transmission Fourier transform infrared spectroscopy (FTIRS) and laser scanning confocal microscopy
(LSCM), respectively. In addition, surface roughness and morphological changes were measured by atomic forcemicrosocopy (AFM)
and LSCM. Substantial chemical degradation, thickness loss, and morpholocal changes occurred in the exposed films, and the
rate of chemical degradation was greater than that due to the thickness loss. This additional chemical loss was attributed
to an inhomogeneous degradation process in which nanoscale localized depressions initiate at certain sites on the surface,
which then enlarge and deepen with exposure time. The results of this study provide a better understanding of the degradation
mechanism and should lead to the development of scientific-based models for predicting the service life of crosslinked amine-cured
epoxy coatings.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago,
IL 相似文献
5.
简述了TCA2003测量机器人全圆观测法机载软件的组成与特点。以陈村水电站大坝的三角网观测为应用实例,基于对其测量平差成果的精度及测量时间分析,将其与传统人工观测的效率进行比较,证明了测量机器人测量的优越性。指出了一些仪器使用及机载软件存在的问题,对自动目标识别(ATR)仪器机载软件的应用开发具有指导作用。 相似文献
6.
In this article, we review the growth of AROB conferences, and assess the various contributions, which have covered digital
life, the artificial brain, artificial society, and evolutionary robots, etc. We analyze the relations between artificial
life, complexity, and intelligent robots, and finally give our view of the expected future of AROB.
This work was presented in part at the 5th International Symposium on Artificial Life and Robotics, Oita, Japan, January 26–28,
2000 相似文献
7.
8.
In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes. 相似文献
9.
Laura Cristóbal Andrade Miguel A. Bernal PampínM.C. Taboada Gómez Pastora M. Bello Bugallo 《Chemical Engineering Research and Design》2014
This paper proposes a methodology to improve the sustainability of industrial processes combining two tools: BAT Analysis and process simulation. Both tools are jointly applied to identify the IF of the analyzed process, so that the most appropriate candidate techniques from an inventory can be selected. The selected alternatives are tested in different scenarios that are evaluated using simulation, which would determine the configuration that best improves the sustainability of the process. The combination of both tools in an integrated methodology will help decision makers to select the most sustainable configuration for a given process. The methodology is validated in a case study: a hydrogen production plant. After analysing several scenarios where different candidate techniques are implemented, results show that the IF identified can be highly improved when the appropriate combination of BAT is applied. 相似文献
10.
《Journal of Nuclear Science and Technology》2013,50(2):183-195
The development work carried out on Fugen NPP is focused on detection of a small leakage on the reactor's inlet feeder pipes at an early stage by an acoustic leak detection method with usage of high-temperature resistant microphones. Specifically, the leak rate of 0.046 m3/h has been chosen as a target detection capability for this system. A cross-correlation technique has been studied for leak detection under low signal-noise ratios. The study shows that the sound diffusion on piping causes distortion of leak signals that results in their low correlation. A leak-location estimator and multi-channel correlation value, associated with estimated leak position, have been employed to detect such low-correlated leak signals. A method based on cross-correlation of signal spectral components has been proposed to deal with non-stationary leak signals. Joint-Time-Frequency-Analysis has been applied to analyze such signals, whilst a Wavelet decomposition technique has been used to extract their short-term spectral fluctuations. Since the spectral components are less affected by signal distortion, they provide higher correlation value and can be applied for leak detection under lower signal-noise ratios. The possibility of detecting and locating a small leakage by the methods proposed has been demonstrated by a number of simulation tests conducted on the Fugen NPP site. 相似文献