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991.
992.
RM Bionta G Blewitt CB Bratton D Casper A Ciocio R Claus M Crouch ST Dye S Errede GW Foster W Gajewski KS Ganezer M Goldhaber TJ Haines TW Jones D Kielczewska WR Kropp JG Learned JM LoSecco J Matthews HS Park LR Price F Reines J Schulz S Seidel E Shumard D Sinclair HW Sobel JL Stone L Sulak R Svoboda G Thornton van der Velde JC C Wuest 《Canadian Metallurgical Quarterly》1987,36(1):30-36
993.
F. Hapla 《Holz als Roh- und Werkstoff》1985,43(1):9-15
From two experimental areas with different thinning grades of a mixed stand of Douglas-fir and spruce, increment cores were taken from 40 Douglas-fir trees, chosen at random in a height of 1.3 m. The properties ring width, latewood percentage, average density, maximum and minimum density were examined from one part of the material by the x-ray densitometric method. The oven-dry density of the remaining part of increment core was examined for additional control. Based on the existing sample data, a significantly higher ovendry density was determined in the untreated area of higher stand density (376 stems/acre) than for the thinned stand (214 stems/acre). The specific gravity (at 10% moisture content) determined by x-ray densitograms shows no statistically valid difference on the average. The possible factors for this result are still being discussed. Further investigations of interactions between individual properties of the Douglas-fir samples obtained by the x-ray densitometric method are being carried out by multiple linear regression analysis. 相似文献
994.
995.
N. F. Starodub 《Journal of Water Chemistry and Technology》2007,29(6):269-276
A brief review of existing methods designed to determine hydrogen peroxide in aqueous media has been presented. Particular attention has been given to biosensor devices enabling us to exercise simple and express control of concentration of the specified compound. 相似文献
996.
A Graphene Field-Effect Device 总被引:2,自引:0,他引:2
In this letter, a top-gated field-effect device (FED) manufactured from monolayer graphene is investigated. Except for graphene deposition, a conventional top-down CMOS-compatible process flow is applied. Carrier mobilities in graphene pseudo-MOS structures are compared to those obtained from the top-gated Graphene-FEDs. The extracted values exceed the universal mobility of silicon and silicon-on-insulator MOSFETs 相似文献
997.
This article provides a brief overview of the history of autonomous mental development as a discipline 相似文献
998.
F. -U. Gast P. S. Dittrich P. Schwille M. Weigel M. Mertig J. Opitz U. Queitsch S. Diez B. Lincoln F. Wottawah S. Schinkinger J. Guck J. Käs J. Smolinski K. Salchert C. Werner C. Duschl M. S. Jäger K. Uhlig P. Geggier S. Howitz 《Microfluidics and nanofluidics》2006,2(1):21-36
We describe a novel microfluidic perfusion system for high-resolution microscopes. Its modular design allows pre-coating of
the coverslip surface with reagents, biomolecules, or cells. A poly(dimethylsiloxane) (PDMS) layer is cast in a special molding
station, using masters made by photolithography and dry etching of silicon or by photoresist patterning on glass or silicon.
This channel system can be reused while the coverslip is exchanged between experiments. As normal fluidic connectors are used,
the link to external, computer-programmable syringe pumps is standardized and various fluidic channel networks can be used
in the same setup. The system can house hydrogel microvalves and microelectrodes close to the imaging area to control the
influx of reaction partners. We present a range of applications, including single-molecule analysis by fluorescence correlation
spectroscopy (FCS), manipulation of single molecules for nanostructuring by hydrodynamic flow fields or the action of motor
proteins, generation of concentration gradients, trapping and stretching of live cells using optical fibers precisely mounted
in the PDMS layer, and the integration of microelectrodes for actuation and sensing. 相似文献
999.
1000.
A method for obtaining accurate reduced order models for hydro-turbines with long penstocks is presented. The inadequacy of the customary first order model is demonstrated. It is also shown that an appropriately chosen second order model provides the necessary accuracy while preserving model simplicity which is essential for ease in controller design, in assessing stability margins, and in power system simulation. 相似文献