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141.
Using different reduction conditions Pd powders have been prepared and characterized by chemisorption and TPO (Temperature Programmed Oxidation) measurements. The amount of carbon deposits introduced during preparation seems to be peculiar to the preparation procedure. The O2 consumption curves attributed to PdO formation have shown two peak minima suggesting strong differences in the accessibility of Pd particles. 相似文献
142.
Prof. Dr. Peter Jeschke Dr. Ralf Nauen Dr. Michael Edmund Beck 《Angewandte Chemie (International ed. in English)》2013,52(36):9464-9485
The destruction of crops by invertebrate pests is a major threat against a background of a continuously rising demand in food supply for a growing world population. Therefore, efficient crop protection measures in a vast range of agricultural settings are of utmost importance to guarantee sustainable yields. The discovery of synthetic agonists selectively addressing the nicotinic acetylcholine receptors (nAChRs), located in the central nervous system of insects, for use as insecticides was a major milestone in applied crop protection research. These compounds, as a result of their high target specificity and versatility in application methods, opened a new innovative era in the control of some of the world′s most devastating insect pests. These insecticides also contributed massively to extending our knowledge of the biochemistry of insect nicotinic acetylcholine receptors. The global economic success of synthetic nAChR agonists as insecticides renders the nicotinic acetylcholine receptor still one of the most attractive target sites for exploration in insecticide discovery. 相似文献
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144.
Zeitschrift für Physik A Hadrons and nuclei - Es werden die Theorien, welche zur Erklärung der Wirkungsweise des schwingenden und selbsttönenden Kristalls bisher aufgestellt worden... 相似文献
145.
K. Beck und H. Beck 《Fresenius' Journal of Analytical Chemistry》1930,82(6-7):266-267
Ohne Zusammenfassung 相似文献
146.
147.
Co(CH3)(PMe3)4 forms 100 % regioselectively with (2‐(2‐diphenylphosphanyl)phenyl)‐1,3‐dioxalane and 2‐diphenylphosphanyl‐pyridine, by elimination of methane, the four‐membered metallacycles Co{(C3O2HC6H3)P(C6H5)2}(PMe3)3 ( 1 ) and Co{(CNC4H3)P(C6H5)2}(PMe3)3 ( 4 ). The regioselectivity is independent of the steric requirement of the ortho substituent in the 2‐diphenylphosphanylaryl‐ligands. Oxidative addition with iodomethane transforms 1 and 4 into octahedral, diamagnetic low‐spin d6 complexes Co(CH3)I‐{(C3O2HC6H3)P(C6H5)2}(PMe3)2 ( 2 ) and Co(CH3)I‐{(CNC4H3)P(C6H5)2}(PMe3)2 ( 5 ). Under an atmosphere of carbon monoxide, insertion into the Co‐C bond results in ring expansion by forming the new assembled phosphanylbenzoyl complexes Co{(C4O3HC6H3)‐P(C6H5)2}CO(PMe3)2 ( 3 ) and Co{(OCNC4H3)P(C6H5)2}CO(PMe3)2 ( 6 ). The three different types of cobaltacycles are supported by X‐ray diffraction of 1 , 3 , 5 and 6 . 相似文献
148.
G. Bollen F. Ames G. Audi D. Beck J. Dilling O. Engels S. Henry F. Herfurth A. Kellerbauer H.-J. Kluge A. Kohl E. Lamour D. Lunney R. B. Moore M. Oinonen C. Scheidenberger S. Schwarz G. Sikler J. Szerypo C. Weber 《Hyperfine Interactions》2001,132(1-4):213-220
Penning trap mass spectrometry has reached a state that allows its application to very short-lived nuclides available from
various sources of radioactive beams. Mass values with outstanding accuracy are achieved even far from stability. This paper
illustrates the state of the art by summarizing the status of the ISOLTRAP experiment at ISOLDE/CERN. Furthermore, results
of mass measurements on unstable rare earth isotopes will be given.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
149.
Anatole Beck 《Israel Journal of Mathematics》1964,2(4):221-228
A man in an automobile searches for another man who is located at some point of a certain road. He starts at a given point and knows in advance the probability that the second man is at any given point of the road. Since the man being sought might be in either direction from the starting point, the searcher will, in general, have to turn around many times before finding his target. How does he search so as to minimize the expected distance travelled? When can this minimum expectation actually be achieved? This paper answers the second of these questions. 相似文献
150.