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Use of methanol as a precipitant to isolate saponified starch-g-polyacrylonitrile from an aqueous alkaline saponification mixture gives a product with a higher water absorbency and better storage stability than that from precipitation with either ethanol, acetone, or isopropanol. Storage stability of the material is strongly dependent on moisture content of the polymer and is enhanced if excess alkali is neutralized before the product is isolated. Absorbent polymers prepared from flour suffer a greater absorbency loss on storage than starch-based polymers. Storage stabilities of drum dried-, freeze dried-, and tray dried products are also examined.  相似文献   
3.
Initial testing on the Japan Atomic Energy Agency Gyrotron Test Stand of ITER-relevant TL components, has shown reasonable efficiencies, but identified that trapped modes between closely located miter bends, as well as mode conversion at miter bends can lead to excessive heating of the connecting waveguides. General Atomics has designed, built, and will test components to address this issue as well as ITER relevant components that have not been tested at the levels of 1 MW, 170 GHz, for extended pulse lengths. Some of the components that will be tested are ultra low loss miter bends, dc breaks, polarizers, power monitors, bellows, waveguide switches, waveguide cooling clamps, etc. Details of the components and test results will be presented.  相似文献   
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The HE11 mode in corrugated circular waveguide can be converted to the EH11 mode (surface wave) by a short, smooth-waveguide phase shift section followed by a short corrugation depth taper. Low-power measurements at 110 GHz in 1.25 in. aluminum waveguide demonstrated approximately 99% conversion with the proper phase shift length. As expected, the conversion efficiency versus length of the phase shifter varied periodically with the period of the TE11 to TM11 beat wavelength. Since the EH11 surface wave is highly attenuated, this type of converter can be used effectively in a compact high-power dummy load.  相似文献   
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A method for preparing and handling large, clean, distortion-free cut surfaces through small and delicate tissues for correlated SEM/TEM examination is described. In this method, tissues are fixed according to conventional protocols; however, instead of critical-point-drying after fixation, tissues are first embedded in polyethylene glycol (PEG), a water-soluble waxy solid. Tissue blocks are easily oriented and sectioned to the desired regions, immersed in a solvent to remove PEG, critical-point-dried, and examined with an SEM. The same tissue blocks can be reworked for TEM by immersing in propylene oxide and embedding in an epoxy resin.  相似文献   
7.
Investigated the correspondence between interview-assessed parental emotional attitudes toward a particular offspring (expressed emotion; EE) and parental affective behavior manifested in direct family interactions for 52 14–19 yr old disturbed but nonpsychotic adolescents. Individual parents who expressed an excessive number of critical comments during the interview (high EE) manifested significantly more mild and harsh criticisms in direct interactions with their offspring than did low-EE parents. A more complex relationship emerged between attitudes and behavior when both parents' emotional attitudes were considered simultaneously. When both parents were high EE, they expressed high levels of mild and harsh criticisms in direct interactions with their offspring. Parental affective behavior in families with only 1 high-EE parent was characterized by high levels of mild criticisms but low levels of harsh criticisms. When both parents were low EE, they manifested few mild or harsh criticisms in direct interactions. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The authors examine how the difficulty of initial training influences the acquisition and transfer of both stimulus-specific knowledge and strategic knowledge not tied to specific stimuli. Participants were asked to discriminate between random polygon stimuli. The order of exposure to very similar and less similar discriminations was varied, in which difficulty of discriminations was defined by the similarity of the stimuli being discriminated. Participants were then transferred to making discriminations between a completely novel set of random polygons. Exposure to discriminations between highly similar stimuli led to eventually faster and more accurate discriminations and superior transfer performance on novel stimuli. The results are explained by a theory of skill acquisition that includes both stimulus-specific knowledge and strategic knowledge that is driven by exposure to specific stimuli, but is not stimulus specific. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
Levels of parental communication deviance (CD), as measured on the Thematic Apperception Test (TAT), were compared among families of schizophrenic patients in two culturally distinct groups. Spanish-speaking Mexican-American parents of schizophrenics completed the TAT in their native language, and CD was coded from their stories by a Spanish-speaking rater. Mexican-American parents had levels of CD that were nearly identical to those of a carefully matched sample of English-speaking Anglo-American parents. Factor scores that measure distinct subtypes of CD also did not differ across groups. The data suggest that levels of CD, despite discriminating between parents of schizophrenics and nonschizophrenics, do not vary across different languages and cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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