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排序方式: 共有10000条查询结果,搜索用时 9 毫秒
961.
M F Haisman 《Ergonomics》1988,31(7):1049-1063
962.
Blanchard Edward B.; Appelbaum Kenneth A.; Guarnieri Patricia; Neff Debra F.; Andrasik Frank; Jaccard James; Barron Kevin D. 《Canadian Metallurgical Quarterly》1988,56(3):427
Tension and vascular headache patients, initially treated with biofeedback and/or relaxation training in either a minimal therapist contact protocol (3 visits) or an intensive individual protocol (10 or 16 visits) were followed-up prospectively for 2 years. In the first study, for the first 6 months of follow-up, half of all patients continued to keep headache diaries and were seen monthly and the other half had only minimal contact. The results at 1-year follow-up, based on 4 weeks of daily headache diaries, revealed equally good maintenance from both treatment protocols and from both follow-up conditions. In Study 2, we found that patients remained improved over pretreatment baseline levels at the 2-year follow-up regardless of initial treatment intensity. Approximately three quarters of vascular patients who were initially improved at posttreatment remained improved at 2 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
963.
Novel aspects of the microstructure of PP/PA blends prepared by reactive compounding as studied by microhardness 总被引:1,自引:0,他引:1
H. G. Fritz Q. Cai M. E. Cagiao L. Giri F. J. Baltá Calleja 《Journal of Materials Science》1995,30(13):3300-3306
The microhardness of injection-moulded i-polypropylene/polyamide (iPP/PA) blends prepared by reactive compounding was determined. The formulation rules and processing technology for the preparation of these alloys was reported previously. iPP/PA compositions between 100/0 and 50/50 using functionalized PP with various degrees of mainchain grafting, were investigated. It is shown that the deviation of microhardness from the additivity law of the single components is mainly due to a decrease in the crystallinity of the iPP phase. The results are discussed in the light of the microstructural variations as revealed by X-ray diffraction methods. 相似文献
964.
William F. Kaukler 《Metallurgical and Materials Transactions A》1988,19(11):2625-2630
An interfluid meniscus oscillates within a cylindrical container when suddenly released from earth's gravity and taken into
a microgravity environment. Oscillations damp out from energy dissipative mechanisms such as viscosity and interfacial friction.
Damping out of the oscillations by the latter mechanism is affected by the nature of the interfacial junction between the
fluid-fluid interface and the container wall. Perfluoromethylcyclohexane and isopropanol in glass were the materials used
for the experiment. The wetting condition of the fluids against the wall changes at the critical wetting transition temperature.
This change in wetting causes a change in the damping characteristics.
This paper is based on a presentation made in the symposium “Experimental Methods for Microgravity Materials Science Research”
presented at the 1988 TMS-AIME Annual Meeting in Phoenix, Arizona, January 25–29, 1988, under the auspices of the ASM/MSD
Thermodynamic Data Committee and the Material Processing Committee. 相似文献
965.
Lang G.R. Dharssi M. Longstaff F.M. Longstaff P.S. Metford P.A.S. Rimmer M.T. 《Computer》1988,21(2):47-57
The authors describe a parallel processing architecture for real-time digital signal processing that has demonstrated virtually 100% data processing efficiency in a number of areas. The Teamed-Architecture Signal Processor (T-ASP) is a field-proven, commercially available optimal system solution to the extremely high computational and I/O rates encountered in modern digital-signal-processing environments. The design of T-ASP involves the consideration and implementation of many architectural concepts used to enhance the performance of a computer, including programmability, parallel processing, vector processing and pipelining, memory interleaving, double cache memories, multiple high-speed I/O interfaces, and segmentation of the processors for elimination of both CPU and data-handling overhead. The authors discuss hardware architecture design and implementation; hardware management; and software architecture design and implementation.<> 相似文献
966.
967.
968.
Maher F. El-Zohry Mohamed A. Abd-Alla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,55(3):209-215
3-(2′-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one was reacted with acetylacetone, ethyl acetoacetate and diethylmalonate in the presence of sodium ethoxide to afford the alkylation products IV, V and VI , Compounds IV, V and VI were reacted with hydrazine hydrate, phenylhydrazine, hydroxylamine hydrochloride, urea and thiourea to yield 3-(2′-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-one derivatives VII-XV . The structures of the synthesized compounds were elucidated by elemental analyses and spectroscopic (IR and XH-NMR) analyses. The prepared compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound. 相似文献
969.
970.