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991.
992.
The influence of the grain size of metallic surfaces on nucleate boiling was investigated experimentally. Surfaces of electrodeposited copper, nickel, brass and chromium were studied with particular emphasis on copper (146 grains per inch to 1678 grains per inch). The pool boiling heat transfer studies were conducted by transferring heat produced electrically through a 6-in. diameter heating surface to a pool of boiling water contained in a glass boiler. A log-log plot of the Q/A versus δTm data showed a definite effect of the grain size of the surface on nucleate boiling heat transfer, the heat transferred at a given δTm increasing as the grain size increased. For copper plated surfaces, the Rohsenow Equation for nucleate pool boiling gave values for Cst and r, which showed a linear relationship when plotted separately against the number of grains per unit length of the surface. A slightly modified form of the Rohsenow correlation has been proposed which takes into account the influence of the grain size of the surface metal for predicting boiling heat transfer. 相似文献
993.
994.
Demonstrates the kinship between M. Buber's (1958, 1966) philosophy of dialog and the contextual therapy (CTH) and family psychiatry of I. Boszormenyi-Nagy (published 1973–1987). Topics discussed, which demonstrate the central issues in Buber's philosophy, include the common order of human existence and existential guilt, meeting others and holding one's ground, distancing and relating, inclusion, and the normative limitation of mutuality between therapist and patient for CTH. The author concludes with an overview of CTH grounded in the concepts of "a dialog of touchstones" and "confirmation of otherness." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
996.
A group (Group A) of 119 college freshmen whose quantitative (Q) scores on the ACE Psychological Examination were 20 or more points higher than their language (L) scores, were compared with a group (Group B) of 110 students (equated with Group A on Q scores) whose Q and L scores did not differ by more than 4 percentile points. Strong VIB scores for 6 occupational scales and for 3 non-occupational scales were compared for the 2 groups. The Group B, with equal Q and L scores, scored significantly higher than Group A on the Interest Maturity VIB scale. No other differences were significant. "In view of the findings… , IM appears to be related to a balance in development between verbal and quantitative abilities." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Fergenson DP Pitesky ME Tobias HJ Steele PT Czerwieniec GA Russell SC Lebrilla CB Horn JM Coffee KR Srivastava A Pillai SP Shih MT Hall HL Ramponi AJ Chang JT Langlois RG Estacio PL Hadley RT Frank M Gard EE 《Analytical chemistry》2004,76(2):373-378
The rapid chemical analysis of individual cells is an analytical capability that will profoundly impact many fields including bioaerosol detection for biodefense and cellular diagnostics for clinical medicine. This article describes a mass spectrometry-based analytical technique for the real-time and reagentless characterization of individual airborne cells without sample preparation. We characterize the mass spectral signature of individual Bacillus spores and demonstrate the ability to distinguish two Bacillus spore species, B. thuringiensis and B.atrophaeus, from one another very accurately and from the other biological and nonbiological background materials tested with no false positives at a sensitivity of 92%. This example demonstrates that the chemical differences between these two Bacillus spore species are consistently and easily detected within single cells in seconds. 相似文献
998.
In the framework of environmental studies, it is important to understand the interaction of humic substances with cations (heavy metals, radionuclides) and to determine their complexation constants in order to evaluate their potential impact on their fate. For this purpose, two techniques have been used: electrospray ionization mass spectrometry, a newly used technique in speciation studies, and time-resolved laser-induced fluorescence spectrometry, a well-known technique for such studies. As a first step, for simplification purposes and to compare both techniques, simple molecules having functional groups present in humic substances have been selected, such as acetic, glycolic, and 4-hydroxyphenylacetic acids. Both techniques have been used to obtain stoichiometries and complexation constants between these simple molecules and europium (III). 相似文献
999.
1000.
Multiplexed liquid arrays for simultaneous detection of simulants of biological warfare agents 总被引:5,自引:0,他引:5
McBride MT Gammon S Pitesky M O'Brien TW Smith T Aldrich J Langlois RG Colston B Venkateswaran KS 《Analytical chemistry》2003,75(8):1924-1930
Liquid array-based multiplexed immunoassays designed for rapid, sensitive, specific, and simultaneous detection of multiple simulants of biological warfare agents have been developed. In both blind and standard laboratory trials, we demonstrate the simultaneous detection of four simulant agents from a single sample. The challenge agents comprise broad classes of pathogens (virus, protein toxins, bacterial spores, vegetative cells). Assay performance of each analyte was optimized, and dose-response curves and the limits of detection (LODs) for individual analytes are presented. Assay performance, including dynamic range, sensitivity, and LODs for liquid arrays and enzyme-linked immunosorbant assay were compared and are shown to be similar. Maximum assay sensitivity is obtained in approximately 1 h, and good sensitivity is achieved in as little as 30 min. Although the sample matrixes are very complex, even for highly multiplexed assays the samples do not exhibit evidence of nonspecific binding, demonstrating that the assays also have high specificity. 相似文献