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31.
32.
K. Fischer und K. Alpers 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1909,17(4):181-190
Ohne ZusammenfassungMitteilung aus dem Chemischen Laboratorium der Auslandsfleischbeschaustelle Bentheim. 相似文献
33.
New Knowledge on Degradation of Starch by Hypochlorite. Part 5. Ageing of Pastes from Oxidized Starch . In order to obtain information on storability of pastes from hypochlorite-oxidized potato starches the changes of viscosity and retrogradation as a function of the degree of oxidation were analized. Apart from a comparison of these results with the pastes of starch dextrines the influence of adding formaldehyde and toluene was investigated. 相似文献
34.
van der Schalk Job; Fischer Agneta; Doosje Bertjan; Wigboldus Dani?l; Hawk Skyler; Rotteveel Mark; Hess Ursula 《Canadian Metallurgical Quarterly》2011,11(2):286
In the present research, we test the assumption that emotional mimicry and contagion are moderated by group membership. We report two studies using facial electromyography (EMG; Study 1), Facial Action Coding System (FACS; Study 2), and self-reported emotions (Study 2) as dependent measures. As predicted, both studies show that ingroup anger and fear displays were mimicked to a greater extent than outgroup displays of these emotions. The self-report data in Study 2 further showed specific divergent reactions to outgroup anger and fear displays. Outgroup anger evoked fear, and outgroup fear evoked aversion. Interestingly, mimicry increased liking for ingroup models but not for outgroup models. The findings are discussed in terms of the social functions of emotions in group contexts. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
35.
This paper uses four case studies to emphasize the fact that field engineering decisions cannot be made without a full understanding of all the technical problems involved. Two of the studies are taken from conventional design-bid-build projects and two are taken from design-build projects in which the ability to strongly influence design in the interest of construction efficiency places a new and increased emphasis on construction and field engineering skills. The cases also show that field engineering decisions frequently address new and unexpected realities, changed conditions, and transient loads, and thus they require high levels of understanding, technical analysis, and creative thought. We emphasize the need for universities and construction engineering programs to develop graduates who are capable of integrating design and construction considerations throughout the project delivery process. We also urge programs to continue to focus strongly on field engineering as the foundation for success in an increasingly complex and technically driven construction industry. 相似文献
36.
Janine Fischer Daniel PröfrockNorbert Hort Regine WillumeitFrank Feyerabend 《Materials Science and Engineering: B》2011,176(11):830-834
Metallic magnesium (Mg) and its alloys are highly suitable for medical applications as biocompatible and biodegradable implant materials. Magnesium has mechanical properties similar to bone, stimulates bone regeneration, is an essential non-toxic element for the human body and degrades completely within the body environment. In consequence, magnesium is a promising candidate as implant material for orthopaedic applications. Protocols using the guideline of current ISO standards should be carefully evaluated when applying them for the characterization of the cytotoxic potential of degradable magnesium materials. For as-cast material we recommend using 10 times more extraction medium than recommended by the ISO standards to obtain reasonable results for reliable cytotoxicity rankings of degradable materials in vitro. In addition primary isolated human osteoblasts or mesenchymal stem cells should be used to test magnesium materials. 相似文献
37.
M. Bieberle E. Schleicher F. Fischer D. Koch H.-J. Menz H.-G. Mayer U. Hampel 《Flow Measurement and Instrumentation》2010,21(3):233-239
Electron beam x-ray tomography is an imaging technique, which can provide cross-sectional images of an object of interest with about 1 mm spatial resolution at frame rates of up to 10,000 frames per second. As a non-intrusive method it is especially suited for studying multiphase flows. For this purpose we devised an experimental limited-angle scan setup which utilizes linear beam deflection to generate radiographic projections. This setup was employed in the study of gas–liquid flow in an experimental flow loop operated at different liquid and gas flow rates. Electron-beam tomography images were compared with image data of a wire-mesh sensor. The latter is a fast but intrusive imaging device which is commonly used in gas–liquid flow imaging and achieves comparable frame rates but at lower spatial resolution. As a novelty we implemented a dual-plane limited-angle electron beam x-ray tomography which allows us to gain information about the phase velocities using cross-correlation data analysis. 相似文献
38.
Richard P. Fischer Arne W. Fliflet 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(9):1297-1313
This paper presents the design and test of asymmetric quasioptical resonators for gyrotron applications, where most of the diffraction output coupling comes from the smaller of two mirrors. A computer code based on scalar diffraction theory is used to calculate the resonator losses and the electric field near the mirrors. Resonators with mirror separations approaching confocal have reduced side lobes in the diffraction patterns, which should allow for better power transmission and focusing. Cold tests have been performed at 94 and 141 GHz to measure the quality factor of the asymmetric resonators as a function of mirror separation and mirror misalignment. Typical resonator parameters include 65 cm mirror separation, 1-3% output coupling and 85% of the losses from the small mirror. A half-symmetric resonator with one flat and one curved mirror has also been investigated. The calculated values of Q are in reasonably good agreement with the cold test measurements. 相似文献
39.
Badeau R.W. Bahar R.I. Bernstein D. Biro L.L. Bowhill W.J. Brown J.F. Case M.A. Castelino R.W. Cooper E.M. Delaney M.A. Deverell D.R. Edmonson J.H. Ellis J.J. Fischer T.C. Fox T.F. Gowan M.K. Gronowski P.E. Herrick W.V. Jain A.K. Meyer J.E. Miner D.G. Partovi H. Peng V. Preston R.P. Somanathan C. Stamm R.L. Thierauf S.C. Uhler G.M. Wade N.D. Wheeler W.R. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1585-1598
A macropipelined CISC microprocessor was implemented in a 0.75-μm CMOS 3.3-V technology. The 1.3-million-transistor custom chip measures 1.62×1.46 cm2 and dissipates 16.3 W. The 100-MHz parts were benchmarked at 50 SPEC marks. The on-chip clocking system and several high-performance logic and circuit techniques are described. Macroinstruction handling, micropipeline management, and control store structures highlight the design architecture. The hierarchical array organization and fast tag comparison technique of the primary cache are discussed. Power estimation procedures are outlined, and the results are compared to measurements. Physical design and verification methods, and CAD tools are also described. After extensive functional verification efforts are described, chip and system test results are presented 相似文献
40.
S. V. Ivanov A. A. Toropov S. V. Sorokin T. V. Shubina I. V. Sedova P. S. Kop’ev Zh. I. Alferov A. Waag H. J. Lugauer G. Reuscher M. Keim F. F. Fischer G. Landwehr 《Semiconductors》1999,33(9):1016-1020
We report the results of an experimental study of molecular-beam epitaxy of ZnSe-based laser heterostructures with a new structure
of the active region, which contains a fractional-monolayer CdSe recombination region in an expanded ZnSe quantum well and
a waveguide based on a variably-strained, short-period superlattice are reported. Growth of a fractional-monolayer CdSe region
with a nominal thickness of 2–3 ML, i.e., less than the critical thickness, on a ZnSe surface (Δa/a∼7%) leads to the formation of self-organized, pseudomorphic, CdSe-enriched islands with lateral dimensions ∼10–30 nm and
density ∼2×1010 cm−2, which serve as efficient centers of carrier localization, giving rise to effective spatial separation of defective regions
and regions of radiative recombination and, as a result, a higher quantum efficiency. Laser structures for optical pumping
in the (Zn, Mg) (S, Se) system with a record-low threshold power density (less than 4 kW/cm2 at 300 K) and continuous-wave laser diodes in the system (Be, Mg, Zn) Se with a 2.5 to 2.8-ML-thick, fractional-monolayer
CdSe active region have been obtained. The laser structures and diodes have an improved degradation resistance.
Fiz. Tekh. Poluprovodn. 33, 1115–1119 (September 1999) 相似文献