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101.
102.
A series of small angle neutron scattering measurements on blends of normal polystyrene (PSH) and labelled (deuterated) polystyrene (PSD) have been made with concentrations of PSD from 5 to 50 mol %. It is shown that the single chain form factor of the polymer in bulk can be obtained from a single concentration measurement for any concentration of labelled molecules, providing the molecular weights of the parent and labelled molecules are the same and the molecular weight distributions are narrow.  相似文献   
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The paper presents the results of research in the convection drying of unidirectional glass fibre bobbins on the basis of which the relations are suggested required to calculate the process of drying in the design of drying equipment.  相似文献   
106.
Field surveys of a series of conjugated diunsaturated straight-chain primary alcohols, acetates, and aldehydes (dienes), including the 3,5-dode-cadienyl, 8,10-dodecadienyl, 3,5-tetradecadienyl, 8,10-tetradecadienyl, 9,11-tetradecadienyl, and 10,12-tetradecadienyl primary alcohols, acetates, and most aldehydes, and the related monounsaturated straight-chain primary alcohols, acetates, and aldehydes (monoenes), including the 3-dodecadienyl alcohol and acetates, attracted the following species from the title families. Diene attractants have been demonstrated for at least onePhyllonorycter sp.,Chionodes lugubrella (Fabr.),Leptostales ferruminaria (Zell.),Drepana bilineata (Pack.),Pyrausta fodinalis (Led.),Notocelia purpurissatana Heinr.,Phaneta alterana Heinr. Monoene attractants were demonstrated forHedya separatana (Kft.),Cydia fletcherana (Kft.),Barbara mappana Free.,Ancylis burgessiana (Zell.),Ancylis nubeculana Clem.,Evippe prunifoliella Cham.,Phlyctaenia coronata tertialis (Gn.), aChionodes sp., a Gelechiidae sp., and an unidentifiedPhyllonorycter sp. Replicated field experiments showed attraction-inhibition relationships for most species. Electroantennagram data are presented forLeptostales ferruminaria andDrepana bilineata.  相似文献   
107.
An algorithm for construction of the reachability domain by the given time instant ? for a nonlinear third order system under the condition of preliminary approach to a predefined point is proposed. All possible cases of location of this point in the motion plane of the system for different values of the time instant ? are studied.  相似文献   
108.
No generally accepted principles and guidelines currently exist to help engineers design local interaction mechanisms that result in a desired global behavior. However, several communities have developed ways of approaching this problem in the context of niched application areas. Because the ideas underlying these approaches are often obscured or underemphasized in technical papers, the authors review the role of self-organization in their work. They provide a better picture of the status of the emerging field of self-organizing systems or autonomic computing.  相似文献   
109.
An all-optical multiplexing technique using wavelength division multiplexing (WDM)-time division multiplexing (TDM) conversion with an electroabsorption wavelength converter has been proposed and demonstrated. The effectiveness of this WDM-TDM conversion technique for various pulsewidth settings was experimentally investigated. The fluctuation of the signal performance, which was inevitably caused by the coherent crosstalk between adjacent pulses in the conventional optical time division multiplexing (OTDM) technique, were successfully suppressed, even in the case of wide pulse duration. High Q-factor performance has been maintained for a wide range of duty ration from 36% to 74%. By introducing this technique to the optical time division multiplexer, a highly stable and high-quality 40-Gb/s optical signal can be effectively produced without generating the short pulse or setting two tributaries at orthogonal polarization states, and without introducing high-speed electronics for signal multiplexing. The WDM-TDM conversion with an electroabsorption wavelength converter was extended to 60-Gb/s operation by using three 20-Gb/s tributaries. A clear eye opening was confirmed for a waveform after the WDM-TDM conversion of the 60-Gb/s signal  相似文献   
110.
C. Viney  A.M. Donald  A.H. Windle 《Polymer》1985,26(6):870-878
Banded textures produced in a thermotropic liquid crystal polymer by shearing between glass slides are examined by using both transmission electron and polarized light microscopy. The periodic variation in director orientation about the shear axis, as measured by light microscopy, is shown to be distinctly different from that indicated by electron diffraction. Measurements of birefringence and observation of Zernicke phase contrast indicate periodic variations in optical properties of the polymer, in step with the bands. Such effects are accounted for in terms of a synchronous rotation of the planar aromatic groups about the molecular chain axes. Evidence for an out-of-plane component of molecular orientation is also presented.  相似文献   
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