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71.
Paul Hirsch und Joseph Kiesgen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1928,55(5):415-423
Ohne Zusammenfassung 相似文献
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B. Gutschwager H. Driescher J. Herrmann H. Hirsch J. Hollandt H. Jahn P. Kuchling C. Monte M. Scheiding 《International Journal of Thermophysics》2011,32(7-8):1429-1439
The Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS) onboard the European?CJapanese space mission BepiColombo to Mercury will be launched in 2014. The MERTIS scientific objective is to identify rock-forming minerals and measure surface temperatures by infrared spectroscopy (7 ??m to 14 ??m) and spectrally unresolved infrared radiometry (7 ??m to 40 ??m). To achieve this goal, MERTIS utilizes two onboard infrared calibration sources, the MERTIS blackbody at 700 K (MBB7) and the MERTIS blackbody at 300 K (MBB3), together with deep space observations corresponding to 3 K. All three sources can be observed one after the other using a rotating mirror system. The leaders of the project MERTIS are the Westfälische University of Münster, institute for planetary investigation, Mr. Prof. Dr. H. Hiesinger (PI) and the DLR, Institute of Planetary Research Berlin-Adlershof, Mr. Dr. J. Helbert (CoPI). Both blackbody radiators have to fulfill the severe mass, volume, and power restrictions of MERTIS. The radiating area of the MBB3 is based on a structured surface with a high-emissivity space qualified coating. The relatively high emissivity of the coating was further enhanced by a pyramidal surface structure to values over 0.99 in the wavelength range from 5 ??m to 10 ??m and over 0.95 in the wavelength range from 10 ??m to 30 ??m. The MBB7 is based on a small commercially available surface emitter in a standard housing. The windowless emitter is an electrically heated resistor, which consists of a platinum structure with a blackened surface on a ceramic body. The radiation of the emitter is expanded and collimated through use of a parabolic mirror. The design requirements and the radiometric and thermometric characterization of these two blackbodies are described in this paper. 相似文献
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Carbon nanotubes and graphene are outstanding materials of the 21st century with a broad spectrum of applications. However, major challenges are faced such as the intrinsically low solubility of both sp2 carbon allotropes. To overcome this hurdle the potential of noncovalent functionalization is summarized with a special focus on the establishment of the perylene bisimide unit as aromatic anchor to the graphitic surface. Rational surfactant design is unmasked as the key to solubilization of the carbon allotropes, while at the same time tailoring their surface properties, or even electronic properties in a fully reversible fashion. 相似文献
76.
D. Thuau M. Abbas S. Chambon P. Tardy G. Wantz P. Poulin L. Hirsch I. Dufour C. Ayela 《Organic Electronics》2014,15(11):3096-3100
We report a low-cost piezoresistive nanocomposite based organic micro electro mechanical system (MEMS) strain sensor that has been combined to an organic field effect transistor (OFET) with the objective of amplifying the sensitivity of the sensor. When the MEMS cantilever is strained by a mechanical deflection, the resulting variation of resistivity influences the gate voltage (VGS) of the OFET and, hence, changes the drain current (IDS) of the transistor. The present combination allows an enhancement of sensitivity to strain by a factor 3.7, compared to the direct detection of resistance changes of the nanocomposite. As a consequence, a low limit of detection of 24 ppm has been estimated in terms of strain transduction efficiency. Furthermore, the organic microsystem exhibits a short response time and operates reversibly with an excellent robustness. 相似文献
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In 2 populations of fruit fly, bidirectional selection and single-pair matings for high and low expression of central excitatory state (CES) in 4 experiments succeeded in producing from one a high, but not a low, CES line, and from the other a low, but not a high, CES line. Compared with results from the selection studies of the blow fly, Phormia regina, in which 1 major gene correlate of CES has been found, the present results suggest that in D. melanogaster there are several gene correlates of CES, opposite alleles of some of which have become fixed in the divergent lines. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
We investigated the expression pattern of the endothelin-A receptor and endothelin 1 genes, the mutations of which affect the development of the mesectodermal derivatives of the neural crest. We show here that endothelin 1 is expressed by the environment of the cephalic neural crest cells invading branchial arches. Later on, while the neural crest-derived tissues of the head continue to express endothelin-A receptor, endothelin 1 is no longer expressed in their environment. 相似文献
79.
Dörte Schumacher Daniela Hirsch Bettina Cämmerer Lothar W. Kroh 《European Food Research and Technology》1996,203(4):385-390
The enzymatic degradation of thermal treated α-glucans with amylolytic enzymes depends on the reaction environment (T, pH, moisture), the degree of polymerisation (DP) and the branch of the substrates as well as on the presence of amino compounds. The chemical changes of the α-glucans due to thermolysis at 180 °C are characterized by means of the amount of reducing substances and the amount of maltooligosaccharides (HPLC). In general the enzymatic degradability of the thermal treated α-glucans is decreased with increasing time of thermolysis, temperature and moisture content. The enzyme activity with the thermal treated α-glucans is diminished in the same way. The addition of amino compounds reduces the enzymatic degradability only at the beginning of the reaction. With increasing time of thermolysis the thermolysates without glycine addition are hardly degradated. As reason for these differences in the enzymatic degradation transglycosylation and non-enzymatic browning reactions (caramalisation/ Maillard-reaction) are assumed. 相似文献
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