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101.
Kaufman R. Gilbert Hadley Wayne B. Hersh Herbert N. 《IEEE transactions on nuclear science》1970,17(3):82-88
In the scintillation mechanism for alkali iodides doped with thallous iodide: 1. Most of the luminescence, and possibly all of it, is from recombination and therefore energy transfer is predominantly from charge transport to thallium. 2. There are two modes of recombination at thallium which differ in the sequence of charge trapping at Tl+. The electron may be trapped before a mobile hole recombines with it, or the hole may be trapped before recombination with a free electron. 3. Thermal hole diffusion is an important process at room temperature and determines which mode a recombination event follows. 4. Both modes of recombination are active. 5. There is non-thermal hole trapping which is a significant part of the scintillator mechanism. 相似文献
102.
Administered 300 items from major inventories of authoritarian and political attitudes (e.g., the Rokeach Dogmatism Scale) to 135 undergraduates. The 300 items were reduced to 77 by selecting those with major factor loadings. Refactoring the 77 produced 25 1st-order factors and 10 2nd-order factors. The 1st-order factors typically referred to groupings of specific attitudes while 2nd-order factors referred to broad patterns which transcend a variety of attitudes. 4 major 2nd-order factors were identified as Religiosity, Political-Economic Liberalism, Authoritarianism, and Restrictiveness; these were found to differentiate Ss according to political and religious affiliations. Examination of items loading on the factors was considered to support the concept of the authoritarian personality but provided less support for M. Rokeach's concepts. The Melvin-Eysenck 2-factor model did not offer enough dimensions to account for the major sources of authoritarian and political attitudes. (French summary) (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
The corrosion performance of both unencapsulated and plastic encapsulated parts has been studied under temperature-humidity-bias (THB) stresses using a patterned test chip with aluminum metallization. The effect of encapsulation materials and ionic contaminants purposely introduced on the chip surface has been determined for both accelerated THB and severe, real life conditions.Unencapsulated test chips exhibited very different THB performance characteristics from encapsulated parts including a near-zero induction time and a shallow post-induction slope on the % failures vs time curve. The induction time and mean-time-to-failure (MTF) for encapsulated devices were strong functions of both the polymeric class of encapsulant and the particular compound employed. At least part of the difference in performance between molding compounds has been attributed to impurities inherent in the compounds. Impurities contributed from conductive epoxies used for die attach also adversely affect the device's MTF, as do normal contaminants present on as-plated leadframes.The environmental factors of temperature, relative humidity and bias greatly affect the performance of encapsulated devices. In this study, the MTF decreased dramatically with bias between 5 and 30 volts, the range over which most devices operate. The acceleration factors relating device performance in an 85°C/85%RH environment to severe, real life conditions were surprisingly small and somewhat dependent on the encapsulant. 相似文献
104.
Attitude formation has been thought to require the characteristics of acquiring and accepting new information. However, some evidence exists to suggest that even though comprehension may be reduced by distracting stimuli, this distraction can actually aid persuasion. In order to test such a hypothesis, two experimental groups were tested under different conditions. Group A listened to an emotional message about segregation, and was tested for comprehension and attitude change. Group B was also exposed to the same persuasive message, but during the message presentation, subjects were shown 35mm color slides containing visual stimuli irrelevant to the message. Results indicated that the distracting stimuli produced a significant reduction in recall of information, while also producing a significant opinion shift. 相似文献
105.
In the upper layer of the global ocean, 2082 in situ chlorophyll biomass values (Chl) are retrieved by concurrent satellite-derived inherent optical properties (IOP). It is found that (1) the phytoplankton absorption coefficient IOP alone does not provide satisfactory (Chl) retrieval; (2) the chromophoric dissolved organic matter (CDOM) absorption coefficient IOP must also be used to obtain satisfactory retrieval through (Chl) alpha a ph + pa CDOM where p is a constant and a ph and aCDOM are, respectively, the phytoplankton and CDOM absorption coefficients; (3) the IOP-based (Chl) retrieval performance is comparable to standard satellite reflectance ratio retrievals (that have CDOM absorption intrinsically embedded within them); (4) inclusion of the total backscattering coefficient IOP does not contribute significantly to (Chl) retrieval; and (5) the new IOP-based algorithm may provide the possibility for future research to establish the actual role of extracellular CDOM from all sources in the intracellular production of chlorophyll biomass. 相似文献
106.
Dunnette Marvin D.; Kirchner Wayne K.; Degidio Joanne 《Canadian Metallurgical Quarterly》1958,42(3):178
The significant intercorrelations among scores on the EPPS, the CPI, and the SVIB are reported for a group of 102 salaried employees of the 3M Company. Comparison of the CPI and EPPS scales generally shows correlations in the expected directions, and correlations between occupational interests and personality variables make "good clinical sense." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
"In a study of Hopi children, a considerable proportion of the Ss apparently exhibited competitive behavior. In terms of scores for competition many Hopi Ss exceeded the mean scores of white groups." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
109.
Berendse F Owens SM Serlemitsos PJ Tueller J Chan KW Soong Y Krimm H Baumgartner WH Ogasaka Y Tamura K Okajima T Tawara Y Yamashita K Misaki K Kunieda H 《Applied optics》2003,42(10):1856-1866
The International Focusing Optics Collaboration for microCrab Sensitivity (InFOCmicroS) balloonborne hard x-ray telescope incorporates graded Pt/C multilayers replicated onto segmented Al foils to obtain the significant effective area at energies previously inaccessible to x-ray optics. Reflectivity measurements of individual foils demonstrate our capability to produce a mass quantity of multilayered foils with a rms roughness of 0.5 nm. The effective area of the completed mirror is 78 and 22 cm2 at 20 and 40 keV, respectively. The measured half-power diameter is 2.0 +/- 0.6 are min (90% confidence). The successful completion of this mirror demonstrates its applicability to future x-ray telescopes such as Constellation-X. 相似文献
110.
Microchip-based purification of DNA from biological samples 总被引:10,自引:0,他引:10
Breadmore MC Wolfe KA Arcibal IG Leung WK Dickson D Giordano BC Power ME Ferrance JP Feldman SH Norris PM Landers JP 《Analytical chemistry》2003,75(8):1880-1886
A microchip solid-phase extraction method for purification of DNA from biological samples, such as blood, is demonstrated. Silica beads were packed into glass microchips and the beads immobilized with sol-gel to provide a stable and reproducible solid phase onto which DNA could be adsorbed. Optimization of the DNA loading conditions established a higher DNA recovery at pH 6.1 than 7.6. This lower pH also allowed for the flow rate to be increased, resulting in a decrease in extraction time from 25 min to less than 15 min. Using this procedure, template genomic DNA from human whole blood was purified on the microchip platform with the only sample preparation being mixing of the blood with load buffer prior to loading on the microchip device. Comparison between the microchip SPE (microchipSPE) procedure and a commercial microcentrifuge method showed comparable amounts of PCR-amplifiable DNA could be isolated from cultures of Salmonella typhimurium. The greatest potential of the microchipSPE device was illustrated by purifying DNA from spores from the vaccine strain of Bacillus anthracis, where eventual integration of SPE, PCR, and separation on a single microdevice could potentially enable complete detection of the infectious agent in less than 30 min. 相似文献