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971.
J. Jens Wolff 《Nachrichten aus der Chemie》1995,43(12):1298-1298
972.
Dorina Trifonova‐Van Haeringen Jozsef Varga Gottfried W. Ehrenstein G. Julius Vancso 《Journal of Polymer Science.Polymer Physics》2000,38(5):672-681
The lamellar organization of melt‐crystallized β‐isotactic polypropylene was studied by atomic force microscopy (AFM) after permanganic etching. Hedritic objects grown at a high crystallization temperature (140–143 °C) were investigated. Essential features of the hedritic development were revealed by the characteristic projections exposed at the sample surface. A three‐dimensional view of the morphology was obtained by AFM. Hedritic growth proceeded mainly by branching around screw dislocations resulting in new lamellae that further developed. Successive lamellar layers often diverged. Deviation from the planar lamellar habit was observed, varying with the position within the hedrite. Twisting of the lamellae also was observed occasionally in the vicinity of the screw dislocations. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 672–681, 2000 相似文献
973.
Thomas Gasevic Dr. Marcel Bamberg Julius Wicke Dr. Michael Bolte Dr. Alexander Virovets Dr. Hans-Wolfram Lerner Prof. Dr. Stefan Grimme Dr. Andreas Hansen Prof. Dr. Matthias Wagner Dr. Markus Bursch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(6):e202314238
A joint theoretical and experimental study on 32 endohedral silafullerane derivatives [X@Si20Y20]− (X=F-I; Y=F-I, H, Me, Et) and -[Cl@Si20H12Y8]− (Y=F-I) is presented. First, we evaluated the structure-determining template effect of Cl− in a systematic series of concave silapolyquinane model systems. Second, we investigated the X−→Si20 interaction energy ( ) as a function of X− and Y and found the largest values for electron-withdrawing exohedral substituents Y. Given that X− ions can be considered as Lewis bases and empty Si20Y20 clusters as Lewis acids, we classify our inseparable host–guest complexes [X@Si20Y20]− as “confined Lewis pairs”. Third, 35Cl NMR spectroscopy proved to be highly diagnostic for an experimental assessment of the Cl−→Si20 interaction as the paramagnetic shielding and, in turn, (35Cl) of the endohedral Cl− ion correlate inversely with . Finally, we disclose the synthesis of [PPN][Cl@Si20Y20] (Y=Me, Et, Br) and provide a thorough characterization of these new silafulleranes. 相似文献
974.
Lukas Biesen Julius Krenzer Nithiya Nirmalananthan-Budau Ute Resch-Genger Thomas J. J. Müller 《Chemical science》2022,13(18):5374
Asymmetrically bridged aroyl-S,N-ketene acetals and aroyl-S,N-ketene acetal multichromophores can be readily synthesized in consecutive three-, four-, or five-component syntheses in good to excellent yields by several successive Suzuki-couplings of aroyl-S,N-ketene acetals and bis(boronic)acid esters. Different aroyl-S,N-ketene acetals as well as linker molecules yield a library of 23 multichromophores with substitution and linker pattern-tunable emission properties. This allows control of different communication pathways between the chromophores and of aggregation-induced emission (AIE) and energy transfer (ET) properties, providing elaborate aggregation-based fluorescence switches.A library of 23 asymmetrically linked aroyl-S,N-ketene acetal solid-state emissive multichromophores accessed by one-pot multicomponent reactions exhibits AIE- and AIEE-active behavior as well as dual emission and potential energy transfer. 相似文献
975.
E. Butter B. Jacobs H. Krmer W. Schmidt J. Stary W. Wolff 《Crystal Research and Technology》1975,10(5):553-560
Ga1–xInxAs epitaxial layers (0.02 ≦ × ≦ 0.12) are grown on (111)-oriented GaAs substrates from nonstoichiometric melts. The etch pit densities – determined by chemical etching – yield values between 2 · 105 cm−2 and 3 · 107 cm−2 and were found to be dependent on composition, layer thickness and cooling rate. X-ray topography of cleaved {110}-planes gives information on layer quality and indicates the existence of stress in the substrate lattice near the heterojunction. The validity of Vegard's law in the investigated concentration range was confirmed by X-ray determination of the lattice constants. The half width of double crystal spectrometer rocking-curves, the epd and the relative intensity of photoluminescence show similar dependence on the composition of the mixed crystal layers. 相似文献
976.
977.
978.
Ottomar Wolff 《Colloid and polymer science》1923,32(1):17-19
Ohne Zusammenfassung 相似文献
979.
L. Rosenthaler C. T. Bennett H. Wolff und Fromme 《Fresenius' Journal of Analytical Chemistry》1923,62(6):253-255
Ohne Zusammenfassung 相似文献
980.
H. Wolff 《Fresenius' Journal of Analytical Chemistry》1917,56(5):261
Ohne Zusammenfassung 相似文献