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51.
GFFs with less than 0.4 dB peak-to-peak error functions are routinely fabricated using commercially available coating machines by utilizing the natural error compensation mechanism of wavelength variable turning point optical monitoring method. 相似文献
52.
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54.
A new porphyrin, peroxyacetic acid uroporphyrin I, has been isolated from the urine of patients with congenital erythropoietic porphyria by reversed phase high performance liquid chromatography. The porphyrin was characterized by high resolution mass spectrometry and by typical chemical reactions of a peroxyacid. 相似文献
55.
This paper tries to introduce the reader to the method of using photochemical re-action to copy holographic optical elements(HOEs)in relief.The holographic blazing gratingso copied is groove depth adjustable phase modulability enlarged through copying and 3.3times the diffraction efficiency(DE)of the original grating.It is expected that the newmethod will lead to the mass production of the light-weight HOEs at low cost. 相似文献
56.
We reported controllable synthesis of ZnS nanocrystal-polymer transparent hybrids by using polymethylmethacrylate (PMMA) as
a polymer matrix. In a typical run, the appropriate amounts of zinc chloride (ZnCl2) and sodium sulfide (Na2S) in the presence of 2-mercaptoethanol (ME) as the organic ligand were well dispersed in H2O/dimethylformamide solution without any aggregation. In addition, the Mn-doped ZnS nanocrystals (NCs) were synthesized with
similar method. Then, ZnS-PMMA hybrids were obtained via free radical polymerization in situ by using ZnS NCs functionalized
with methacryloxypropyltrimethoxysilane (MPS). FT-IR characterization indicates the formation of robust bonding between ZnS
NCs and the organic ligand. The TEM images show that ZnS NCs are well dispersed in PMMA matrix, and particle size of as-prepared
ZnS NCs is about 2.6 nm, in agreement with the computing results of Brus’s model and Debye–Scherrer formula. The photoluminescence
measurements present that ZnS NCs, Mn-doped ZnS NCs, and ZnS/PMMA hybrid show good optical properties. 相似文献
57.
Yaping Guo 《European Polymer Journal》2007,43(6):2292-2297
Polyaniline (PANI) nanofibers with interconnected network-like structures were electropolymerized on stainless steel substrates by galvanostatic electrolysis. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FTIR). The results show that PANI and gels (mixtures of oligomer, dopant and aniline) form simultaneously during the electrochemical deposition. The gels play an important role in the formation of PANI nanofibers. The PANI formed in the early stage of polymerization is subject to secondary growth along one dimension, since the nucleation sites are suppressed by the wrapped gels. The dendritic degree of PANI nanofibers is related to dopants, and the order is as follows: PANI-H3PO4 > PANI-H2SO4 > PANI-HNO3. No nanofibers are obtained using CH3COOH as dopants due to the high solubility of PANI-CH3COOH. 相似文献
58.
An interval-parameter fuzzy linear programming method (IFMOLP) is proposed in this study for multiple objective decision-making
under uncertainty. As a hybrid of interval-parameter and fuzzy methodologies, the IFMOLP incorporates interval-parameter linear
programming and fuzzy multiobjective programming approaches to form an integrated optimization system. The method inherits
advantages of interval-parameter programming, and allows uncertainties and decision-makers’ aspirations to be effectively
communicated into its programming processes and resulting solutions. Membership functions for both objectives and constraints
are formulated to reflect uncertainties in different system components and their interrelationships. An interactive solution
procedure has been developed based on solution approaches of the interval-parameter and fuzzy programming techniques, plus
necessary measures for handling the multiobjective feature. A didactic example is provided in the paper to illustrate the
detailed solution process. Possibilities of further improvements by seeking Pareto optimum and incorporating flexible preference
within constraints are also discussed. 相似文献
59.
Liangqi Gui Wei Guo ZuYin Zhang Shu Duan 《International Journal of Infrared and Millimeter Waves》2004,25(1):63-70
The image displaying methods used in a millimeter wave radiometric imaging system have great influence on its imaging quality. In order to obtain high quality millimeter wave radiometric images, intensive studies on the image displaying methods are needed. This paper describes the image displaying method of Ground-based 8mm Millimeter Wave Radiometric Imaging (GMWRI) system and compares two different image displaying methods. The experimental results prove the unequal size element arc displaying method fits GMWRI system better. 相似文献
60.