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161.
M. Abdel-Bary S. Abdel-Samad K-Th. Brinkmann H. Clement J. Dietrich E. Doroshkevich S. Dshemuchadse K. Ehrhardt A. Erhardt W. Eyrich D. Filges A. Filippi H. Freiesleben M. Fritsch W. Gast J. Georgi A. Gillitzer J. Gottwald D. Hesselbarth H. J?ger B. Jakob R. J?kel L. Karsch K. Kilian H. Koch M. Krapp J. Kre? E. Kuhlmann A. Lehmann S. Marcello S. Marwinski S. Mauro W. Meyer P. Michel K. M?ller H. P. Morsch H. M?rtel L. Naumann N. Paul L. Pinna C. Pizzolotto Ch. Plettner S. Reimann M. Richter J. Ritman E. Roderburg A. Schamlott P. Sch?nmeier W. Schroeder M. Schulte-Wissermann T. Sefzick F. Stinzig M. Steinke G. Y. Sun A. Teufel W. Ullrich G. J. Wagner M. Wagner R. Wenzel A. Wilms P. Wintz S. Wirth P. Wüstner P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2010,46(1):27-44
162.
J. I. Pacold J. A. Bradley B. A. Mattern M. J. Lipp G. T. Seidler P. Chow Y. Xiao Eric Rod B. Rusthoven J. Quintana 《Journal of synchrotron radiation》2012,19(2):245-251
Core–shell X‐ray emission spectroscopy (XES) is a valuable complement to X‐ray absorption spectroscopy (XAS) techniques. However, XES in the hard X‐ray regime is much less frequently employed than XAS, often as a consequence of the relative scarcity of XES instrumentation having energy resolutions comparable with the relevant core‐hole lifetimes. To address this, a family of inexpensive and easily operated short‐working‐distance X‐ray emission spectrometers has been developed. The use of computer‐aided design and rapid prototype machining of plastics allows customization for various emission lines having energies from ~3 keV to ~10 keV. The specific instrument described here, based on a coarsely diced approximant of the Johansson optic, is intended to study volume collapse in Pr metal and compounds by observing the pressure dependence of the Pr Lα emission spectrum. The collection solid angle is ~50 msr, roughly equivalent to that of six traditional spherically bent crystal analyzers. The miniature X‐ray emission spectrometer (miniXES) methodology will help encourage the adoption and broad application of high‐resolution XES capabilities at hard X‐ray synchrotron facilities. 相似文献
163.
We show that every strongly jump-traceable set is K-trivial. Unlike other results, we do not assume that the sets in question are computably enumerable. 相似文献
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Rod White 《Accreditation and quality assurance》2011,16(1):31-41
The latest version of the International Vocabulary of Metrology gives a meaning of measurement restricted to quantities that can be represented by numerical values and placed in an ordinal
sequence. This restrictive definition fits poorly with both the colloquial and the wider scientific understanding of measurement.
This paper suggests an extension to the metrological definition of measurement, based on the measurement classification scheme
of Stevens, to incorporate non-numerical and nominal measurements. The more inclusive definition and the classification scheme
offers insights into the utility, metrological traceability, and limitations of measurements and uncertainty treatments, and
enables clarification of other measurement-related definitions. 相似文献
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Bjrn Bohman Monica M. Y. Tan Ryan D. Phillips Adrian Scaffidi Alexandre N. Sobolev Stephen A. Moggach Gavin R. Flematti Rod Peakall 《Angewandte Chemie (International ed. in English)》2020,59(3):1124-1128
Bioactive natural products underpin the intriguing pollination strategy used by sexually deceptive orchids. These compounds, which mimic the sex pheromones of the female insect, are emitted in particular blends to lure male insect pollinators of specific species. By combining methods from field biology, analytical chemistry, electrophysiology, crystallography, and organic synthesis, we report that an undescribed β‐hydroxylactone, in combination with two specific hydroxymethylpyrazines, act as pollinator attractants in the rare hammer orchid Drakaea micrantha. This discovery represents an unusual case of chemically unrelated compounds being used together as a sexual attractant. Furthermore, this is the first example of the identification of pollinator attractants in an endangered orchid, enabling the use of chemistry in orchid conservation. Our synthetic blend is now available to be used in pollinator surveys to locate suitable sites for plant conservation translocations. 相似文献
170.
Electron diamagnetic effect on axial force in an expanding plasma: experiments and theory 总被引:1,自引:0,他引:1
The axial force imparted from a magnetically expanding current-free plasma is directly measured for three different experimental configurations and compared with a two-dimensional fluid theory. The force component solely resulting from the expanding field is directly measured and identified as an axial force produced by the azimuthal current due to an electron diamagnetic drift and the radial component of the magnetic field. The experimentally measured forces are well described by the theory. 相似文献