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21.
    
Ohne ZusammenfassungMitteilung aus dem Chemischen Laboratorium der Auslandsfleischbeschaustelle Bentheim.  相似文献   
22.
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   
23.
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   
24.
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   
25.
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   
26.
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   
27.
Gallium selenide (GaSe) is a layered compound, which has been exploited in nonlinear optical applications and photodetectors due to its anisotropic structure and pseudodirect optical gap. Theoretical studies predict that its 2D form is a potential photocatalyst for water splitting reactions. Herein, the photoelectrochemical (PEC) characterization of GaSe nanoflakes (single‐/few‐layer flakes), produced via liquid phase exfoliation, for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in both acidic and alkaline media is reported. In 0.5 m H2SO4, the GaSe photoelectrodes display the best PEC performance, corresponding to a ratiometric power‐saved metric for HER (Φsaved,HER) of 0.09% and a ratiometric power‐saved metric for OER (Φsaved,OER) of 0.25%. When used as PEC‐type photodetectors, GaSe photoelectrodes show a responsivity of ≈0.16 A W?1 upon 455 nm illumination at a light intensity of 63.5 µW cm?2 and applied potential of ?0.3 V versus reversible hydrogen electrode (RHE). Stability tests of GaSe photodetectors demonstrated a durable operation over tens of cathodic linear sweep voltammetry scans in 0.5 m H2SO4 for HER. In contrast, degradation of photoelectrodes occurred in both alkaline and anodic operation due to the highly oxidizing environment and O2‐induced (photo)oxidation effects. The results provide new insight into the PEC properties of GaSe nanoflakes for their exploitation in photoelectrocatalysis, PEC‐type photodetectors, and (bio)sensors.  相似文献   
28.
A nested taper structure in InGaAsP/InP, using only horizontally tapered waveguides, transforms the fundamental mode of an integrated waveguide to the mode profile of a singlemode fibre. Taper tips below 300 nm width have been achieved with standard technology. Very first measurement results show an insertion loss of only 4 dB for a 1 mm long device without any antireflective coating or immersion fluid.<>  相似文献   
29.
A semiconductor switching technique has been utilized to produce 30-300 ps variable duration CO2 laser pulses of 0.5-MW peak power. Eight passes through a 1.2-m long, UV-preionized, 3-atm TE CO2 amplifier raise the output laser peak power to the 1010 W level. Sampling the amplifier gain in linear and saturated regimes using CO2 laser radiation ranging from CW to 30 ps pulse length permits comparison with computer modeling of picosecond CO2 pulse amplification. The potential for further peak power scaling of picosecond molecular lasers is discussed  相似文献   
30.
Fischer  U. 《Electronics letters》1992,28(14):1305-1306
With low chirp direct modulation of a commercially available lambda =1.55 mu m BH DFB laser module at 10 Gbit/s, a transmission experiment over 69 km of non-dispersion-shifted singlemode fibre was successfully performed. The scheme is based on optical FM by modulation of the injection current with subsequent conversion into intensity modulation by means of a fibre Mach-Zehnder interferometer.<>  相似文献   
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