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181.
182.
Ott S Borgström M Kritikos M Lomoth R Bergquist J Akermark B Hammarström L Sun L 《Inorganic chemistry》2004,43(15):4683-4692
A model of the iron hydrogenase active site with the structure [(mu-ADT)Fe2(CO)6] (ADT = azadithiolate (S-CH2-NR-CH2-S), (2: R = 4-bromophenyl, 3: R = 4-iodophenyl)) has been assembled and covalently linked to a [Ru(terpy)2]2+ photosensitizer. This trinuclear complex 1 represents one synthetic step toward the realization of our concept of light-driven proton reduction. A rigid phenylacetylene tether has been incorporated as the linking unit in 1 in order to prolong the lifetime of the otherwise short-lived [Ru(terpy)2]2+ excited state. The success of this strategy is demonstrated by comparison of the photophysical properties of 1 and of two related ruthenium complexes bearing acetylenic terpyridine ligands, with those of [Ru(terpy)2]2+. IR and electrochemical studies reveal that the nitrogen heteroatom of the ADT bridge has a marked influence on the electronic properties of the [Fe2(CO)6] core. Using the Rehm-Weller equation, the driving force for an electron transfer from the photoexcited *[Ru(terpy)2]2+ to the diiron site in 1 was calculated to be uphill by 0.59 eV. During the construction of the trinuclear complex 1, n-propylamine has been identified as a decarbonylation agent on the [(mu-ADT)Fe2(CO)6] portion of the supermolecule. Following this procedure, the first azadithiolate-bridged dinuclear iron complex coordinated by a phosphine ligand [(mu-ADT)Fe2(CO)5PPh3] (4, R = 4-bromophenyl) was synthesized. 相似文献
183.
W. A. Taylor D. J. Jamriska V. T. Hamilton R. C. Heaton D. R. Phillips R. C. Staroski J. B. Garcia J. G. Garcia M. A. Ott 《Journal of Radioanalytical and Nuclear Chemistry》1995,195(2):287-295
Since the mid-1970s the Los Alamos Medical Radioisotope Program has been irradiating target materials to produce and recover radioisotopes for applications in medicine, environmental science, biology, physics, materials research, and other disciplines where radiotracers find utility. By necessity, the chemical processing of targets and the isolation of radioisotopes generates radioactive waste materials. In recent years there have been federal mandates requiring us to discontinue the use of hazardous materials and to minimize radioactive waste volumes. As a result, substantial waste reduction measures have been introduced at the irradiation facility, in processing approaches, and even in the ways the product isotopes are supplied to users. 相似文献
184.
Miniaturized magnetic guide for neutral atoms 总被引:1,自引:0,他引:1
J. Fortagh H. Ott A. Grossmann C. Zimmermann 《Applied physics. B, Lasers and optics》2000,70(5):701-708
We describe the principle and realization of a miniaturized magnetic guide for neutral atoms. The magnetic guide in our experiment
is formed by a micrometer-sized current-carrying wire which is attached to a second, thick wire. The conductors are electrically
insulated from each other. The combined magnetic field of both conductors provides an approximately linear trapping potential
which establishes a magnetic guide along the surface of the thin wire. The miniaturized waveguide is filled with rubidium
atoms from a magneto-optical trap (MOT) by first loading the atoms into a spherical magnetic quadrupole trap which is subsequently
transformed into the linear potential of the waveguide. As thermal source for Rb atoms we use an alkali metal dispenser which
is located close to the center of the MOT. This novel method is compatible with ultrahigh vacuum conditions and we achieved
lifetimes of the magnetically trapped atoms up to 100 s.
Received: 18 October 1999 / Published online: 24 March 2000 相似文献
185.
186.
Ohne Zusammenfassung
Adolf Ott, Diss. (1923). 相似文献
187.
stud. phil. Hans Ott 《Monatshefte für Chemie / Chemical Monthly》1905,26(3):335-348
Ohne ZusammenfassungZum SchlÜsse sei mir gestattet, meinem hochverehrten Lehrer, Herrn Prof. Dr. Guido Goldschmiedt, fÜr die UnterstÜtzung, die er mir bei der AusfÜhrung dieser Arbeit in Rat und Tat in so reichem Ma\e angedeihen lie\, meinen aufrichtigsten und innigsten Dank zu sagen. 相似文献
188.
189.
190.
Ott Biermann 《Mathematische Annalen》1896,48(3):393-400
Ohne Zusammenfassung 相似文献