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61.
62.
Reactions of tBu2P? P?P(Br)tBu2 with Phosphanes A Route to Variously Substituted Phosphinophosphinidene-phosphoranes tBu2P? P?P(Br)tBu2 1 reacts with PR3 [R3 = Et3, tBu3, Ph3, (NMe2)3, (NEt2)3, (NEt2)2Me, Me2SiMe3] according to tBu2P? P?P(Br)tBu2 + PR3 → tBu2P? P?PR3 + tBu2PBr While 1 decomposes above ?30°C yielding tBu2PBr and the cyclophosphanes (tBu2P)3P3 and (tBu2P)4P4, there is no condensation to give any cyclophosphanes from the intermediately formed tBu2P? P in the presence of PR3. The chlorophosphanes tBu2PCl, tBuPPhCl, (Et2N)2PCl and Ph2PCl as well as (CF3)2PBr react quite analogously to the above equation yielding tBu2P? P?P(Cl)tBu2, tBu2P? P?PtBuPhCl, tBu2P? P?P(NEt2)2Cl and tBu2P? P?P(NEt2)2Br. 相似文献
63.
U. Müller K. Sattler J. Xhie N. Venkateswaran G. Raina 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,19(4):319-321
We report a topographic study of platinum clusters on highly-oriented pyrolytic graphite (HOPG) using a scanning tunneling microscope operating in air. The particles were produced by evaporation of platinum onto the graphite-surface in high vacuum. The simultaneous finding of single platinum atoms, clusters and small particles on an otherwise clean and atomically flat surface shows that the platinum-HOPG surface interaction is strong enough to yield stable images of Pt atoms and yet is not strong enough to annihilate the Pt-Pt interaction. Small flat platinum clusters on HOPG can be imaged with atomic resolution of the cluster and the surrounding graphite lattice. We show the adsorption site distribution for the monomers. The Pt-dimers show a very broad bond length distribution on graphite with an average of 2.46 Å. We found two types of Pt-trimers, one which is almost linear and one of triangular form. The average nearest neighbour distance of the trimers is 2.61 Å. 相似文献
64.
Crystal Structure of Sodium Dihydrogencyamelurate Tetrahydrate Na[H2(C6N7)O3] · 4 H2O Sodium dihydrogencyamelurate‐tetrahydrate Na[H2(C6N7)O3]·4 H2O was obtained by neutralisation of an aqueous solution, previously prepared by hydrolysis of the polymer melon with sodium hydroxide. The crystal structure was solved by single‐crystal X‐ray diffraction ( a = 6.6345(13), b = 8.7107(17), c = 11.632(2) Å, α = 68.96(3), β = 87.57(3), γ = 68.24(3)°, V = 579.5(2) Å3, Z = 2, R1 = 0.0535, 2095 observed reflections, 230 parameters). Both hydrogen atoms of the dihydrogencyamelurate anion are directly bound to nitrogen atoms of the cyameluric nucleus, thus proving the preference of the keto‐tautomere in salts of cyameluric acid in the solid‐state. The compound forms a layer‐like structure with an extensive hydrogen bonding network. 相似文献
65.
66.
G. J. Simonis J. P. Sattler T. L. Worchesky R. P. Leavitt 《International Journal of Infrared and Millimeter Waves》1984,5(1):57-72
We have used non-dispersive Fourier-transformspectroscopic techniques to measure the complex indices of refraction of materials between frequencies of 120 and 550 GHz. Results are presented for crystal quartz, crosslinked polystyrene (Rexolite 1422), glass-loaded polytetrafluoroethylene (Duroid 5880) and a nickel ferrite (Trans-Tech 2-111). These results are compared with other data on these materials in this frequency range. The accuracy of these measurements yields a considerable improvement in the near-millimeter-wave characterization of several of these materials. For materials other than crystal quartz, our results are the first measurements of their properties over the entire frequency range studied. 相似文献
67.
68.
H. Sattler 《Colloid and polymer science》1963,187(1):12-18
Zusammenfassung Die molekulare Orientierung von Spinnf?den aus Poly?thylenterephthalat wird durch die Doppelbrechung und durch das Schrumpfverm?gen
der F?den bei Temperaturen um 100‡ beschrieben. Aus der Abh?ngigkeit dieser Kenngr?\en von den Spinndaten und ihrem gegenseitigen
Zusammenhang ergeben sich Vorstellungen über Natur und Entstehung der molekularen Orientierung der Spinnf?den.
Ver?ffentlicht anl?\lich des 100j?hrigen Bestehens der Farbwerke Hoechst AG. am 11. Januar 1963. 相似文献
69.
Daniel Kolbe Anna Beczkowiak Thomas Diehl Andreas Koglbauer Matthias Sattler Matthias Stappel Ruth Steinborn Jochen Walz 《Hyperfine Interactions》2012,212(1-3):213-220
We demonstrate a reliable continuous-wave (cw) laser source at the 1 S–2 P transition in (anti)hydrogen at 121.56 nm (Lyman-α) based on four-wave sum-frequency mixing in mercury. A two-photon resonance in the four-wave mixing scheme is essential for a powerful cw Lyman-α source and is well investigated. 相似文献
70.
Lars E. Sattler Prof. Dr. Gerhard Hilt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(2):605-608
The synthesis of 1,3-oxazoles from symmetrical and unsymmetrical alkynes was realized by an iodonium cation-pool electrolysis of I2 in acetonitrile with a well-defined water content. Mechanistic investigations suggest that the alkyne reacts with the acetonitrile-stabilized I+ ions, followed by a Ritter-type reaction of the solvent to a nitrilium ion, which is then attacked by water. The ring closure to the 1,3-oxazoles released molecular iodine, which was visible by the naked eye. Also, some unsymmetrical internal alkynes were tested and a regioselective formation of a single isomer was determined by two-dimensional NMR experiments. 相似文献