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71.
This is the first of a series of articles on ionic and molecular transport processes and related properties of paint films. The intention is to correlate adhesion and initiation of corrosion to these relevant physical and chemical properties. Chemical formulas and structure of three vinyl–three epoxy– and one polyurethane–paint system are given in this article. Each paint has been formulated to meet appropriate military specifications. Subsequent articles will deal with dynamic mechanical properties, small angle x-ray scattering measurements of porosity, and transport properties. 相似文献
72.
Reviews the book, Recent developments in psychoanalysis by Morris N. Eagle (see record 1987-98252-000). This volume is a timely and important addition to psychoanalytic literature. Eagle states that it is "intended as a systematic overview of recent ideas with the aim of providing a coherent account of the current status of psychoanalytic theory." His overview is generally fair, but penetrating, and exposes much of the irrationality and confusion that have plagued psychoanalytic thinking recently. He suggests that this confusion has arisen out of the tendency of psychoanalytic theorists to ignore advances in other areas of psychological research and related fields, particularly in the area of psychology of child development. Further confusion has been created by their attempt to formulate new concepts and ideas within the framework of classical Freudian metapsychology, which is rooted in instinct theory. These attempts, in many cases, have led to the use of a psychoanalytic language full of jargon, rendering theoretical formulations expressed in this way totally incomprehensible and aloof from logical consideration, while pretending to add metapsychological depth. Ultimately, however, he tries to elucidate the many real contributions to psychoanalytic theory by these theorists and to integrate their work into a coherent framework. His efforts in this regard reflect a sympathetic approach to the aims and ideals of psychoanalysis as a social science and a form of therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Mainstream American journalism rests on a pluralist model of democracy that conserves the status quo, essentializes culture, and trivializes diversity. A very different understanding of diversity emerges from a multiculturalist perspective that questions existing arrangements, posits a relational view of culture, and defines diversity in terms of patterns of discrimination and inequality. A case study of coverage of a local issue in the mainstream and minority press underpins a discussion of the importance of diversifying journalism by restructuring the American press. Journalism diversity matters most not only as it heightens sensitivity to cultural differences but as it strengthens the role of minority media in the struggle to achieve the social justice and political parity that a culturally diverse society demands. 相似文献
74.
Slagging coal gasifiers suffer corrosive attack on the refractory liner and these interactions were thermochemically simulated. The slag is observed to penetrate the refractory, which complicates modeling the phase behavior of the slag-penetrated interior of the refractory. A simple strategy was adopted such that stepwise changes in composition with decreasing slag content were assumed to account for the compositional changes as slag penetrates the refractory. The thermochemical equilibrium calculations following this strategy typically yielded three solution phases as well as the stoichiometric crystalline phases AlPO4 and Ca3(PO4)2 depending on composition/penetration. Under some conditions a slag liquid miscibility gap exists such that two slag liquids coexist. 相似文献
75.
In an attempt to understand the Schottky barrier behavior of Ti/Pt/GaAs and Pt/Ti/ GaAs bimetal Schottky diodes, we have investigated
the interfacial morphology of Ti and Pt thin films on GaAs(l00) substrate. The characterization was based on coverage profiling
of Auger electron spectroscopy in conjunction with transmission electron microscopy. Emphasis was placed on film uniformity
and atomic interdiffusion. The results showed Ga and As outdiffusion in Pt/GaAs interface and some oxygen incorporated in
Ti film, but no evidence of clustering for both metal/GaAs systems. 相似文献
76.
Marcus A. Worsley Peter J. Pauzauskie Sergei O. Kucheyev Joseph M. Zaug Alex V. Hamza Joe H. Satcher Theodore F. Baumann 《Acta Materialia》2009,57(17):5131-5136
Here, we present the synthesis and characterization of low-density single-walled carbon nanotube-based aerogels (SWNT-CA). Aerogels with varying nanotube loading (0–55 wt.%) and density (20–350 mg cm?3) were fabricated and characterized by four-probe method, electron microscopy, Raman spectroscopy and nitrogen porosimetry. Several properties of the SWNT-CAs were highly dependent upon nanotube loading. At nanotube loadings of 55 wt.%, shrinkage of the aerogel monoliths during carbonization and drying was almost completely eliminated. Electrical conductivities are improved by an order of magnitude for the SWNT-CA (55 wt.% nanotubes) compared to those of foams without nanotubes. Surface areas as high as 184 m2 g?1 were achieved for SWNT-CAs with greater than 20 wt.% nanotube loading. 相似文献
77.
Theodore H. H. Pian Pin Tong 《International journal for numerical methods in engineering》1986,22(1):173-181
An examination of the variational formulations confirms the similarity between the incompatible displacement model and the assumed stress hybrid model that was pointed out by Irons in 1972. But the basic differences between the two are also identified. For 8-node solid elements the assumed stress terms obtained through a rational procedure also agree with those deduced by Irons purely from his physical insight. 相似文献
78.
Cured samples of a nitrogen-containing acetylene-terminated resin, N,N′-(1,3-phenylene-dimethylidene)bis(3-ethynylaniline), have been heated at 10°C/min up to 900°C in a pyroprobe attached to a gas chromatograph/mass spectrometer (GC/MS). Analysis of the volatiles evolved during heating identified both gases and higher boiling compounds. The major higher boiling compounds are benzene, toluene, xylene, aniline, benzonitrile, m-methylaniline, and m-methylbenzonitrile; the gases include ammonia, methane, and traces of carbon dioxide. Correlations between sample temperature and the evolution of each of these compounds have been made. The onset of all volatile formation occurs between 450 and 500°C. The higher boiling volatiles peak, then end by approximately 700°C, while the gases peak then fall off but are still being evolved at 900°C. Average weight loss measurements of 13.6% at 700°C and 15.7% at 900°C agree with previously published thermogravimetric analysis (TGA) data. © 1993 John Wiley & Sons, Inc. 相似文献
79.
80.
S. Theodore Chandr N. B. Balamurugan M. Bhuvaneswari N. Anbuselvan N. Mohankumar 《半导体学报》2015,36(6):064003-6
A compact model is proposed to derive the charge density of the AlInSb/InSb HEMT devices by considering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with applied gate voltage. The proposed model considers the Fermi level dependence of charge density and vice versa. The analytical results generated by the proposed model are compared and they agree well with the experimental results. The developed model can be used to implement a physics based compact model for an InSb HEMT device in SPICE applications. 相似文献