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81.
Jester SS Idelson A Schmitz D Eberhagen F Höger S 《Langmuir : the ACS journal of surfaces and colloids》2011,27(13):8205-8215
Shape-persistent rigid phenylene-ethynylene-butadiynylenes form lamellar self-assembled monolayers (SAMs) at the HOPG/TCB interface, which were studied by scanning tunneling microscopy (STM) with submolecular resolution. Substitution of the terminating acetylene functions with polar cyanopropyldimethylsilyl groups leads to 2D phase separation and defined rod-rod interactions, which determine the packing distances between the rigid rods. The results stimulated the connection of rigid rods via septiarylene clamp units. They covalently link two rigid rod units and define the intramolecular rod-rod distance that matches the alkoxy substituent chain lengths. The systems can be described as half-ring structures of two rigid rods connected via a rotatable joint unit. These acetylene-terminated half-ring structures were also oligomerized under Cu and Pd catalysis to yield defined acyclic and cyclic oligomers. Detailed STM studies decoded the molecular origin of the surface patterning of such systems. The dodecyloxy side chains are adsorbed along the HOPG main axes and, together with the alkoxy backbone angle, determine the adsorption direction of the adlayers. 相似文献
82.
83.
84.
Further development of a model for the production of strange particles in nucleus-nucleus collisions
A previously proposed model for the production of neutral strange particles in nucleus-nucleus collisions, based on the Additive Quark Model and nuclear cascading, is further developed. The model predictions on neutral strange particle multiplicities, transverse momentum and rapidity distributions are compared with the existing oxygen- and sulphur-nucleus data at 200 GeV per nucleon. The predictions for central PbPb collisions are presented and discussed in some detail. 相似文献
85.
86.
V. Blobel H. Fesefeldt P. Freund C. Geich-Gimbel B. Hellwig U. Idschok J.W. Lamsa D. Lüers D. Mönkemeyer N. Schmitz B. Schröder B.M. Schwarzschild 《Nuclear Physics B》1975,88(1):18-40
In this paper we study correlations in multiparticle final states from pp interactions at 12 and 24 GeV/c. In an attempt to distinguish true dynamical correlations from the consequences of kinematics together with PT damping and the leading-particle effect, we compare the data with an independent-emission model which reproduces the single-particle spectra and also with a model that simulates a fragmentation mechanism. We investigate the forward-backward particle configurations and in particular the multiplicity imbalance and charge transfer, defining forward-backward by the largest rapidity gap as well as simply by c.m.s. hemispheres. We also study clustering by looking at distributions of the dispersions in longitudinal rapidity. From the comparison of the data with the models we find clear evidence for dynamical correlations of a sort one would expect from fragmentation-type mechanisms. We also find indications of non-fragmentation formation of neutral meson clusters. 相似文献
87.
R. Brandelik W. Braunschweig K. Gather V. Kadansky K. Lübelsmeyer P. Mättig H.-U. Martyn G. Peise J. Rimkus H.G. Sander D. Schmitz A. Schultz von Dratzig D. Trines W. Wallraff H. Boerner H.M. Fischer H. Hartmann G. Zobernig 《Physics letters. [Part B]》1980,94(1):91-95
Inclusive K0-production has been measured in e+e- annihilation at a center of mass energy of about W = 30 GeV. The ratio of K0 + K0 production to μ+μ- production is RK0 = 5.6 ± 1.1 (statist. error) ± 0.8 (system.error) This value is about a factor of three higher than RK0 at W = 7 GeV. The cross sections (s/β) dσ/dx is consistent with a scaling behaviour. 相似文献
88.
R. Brandelik W. Braunschweig H.-U. Martyn H.G. Sander D. Schmitz W. Sturm W. Wallraff D. Cords R. Felst R. Fries E. Gadermann H. Hultschig P. Joos W. Koch U. Kotz H. Krehbiel D. Kreinick S. Yamada 《Physics letters. [Part B]》1977,67(3):358-362
Charged hadron production via has been measured for s values between 13 and 25 GeV2. Inclusive cross sections and the evidence for scaling are presented. 相似文献
89.
90.
The total hadronic cross section for e+e− annihilation between 3.1 and 4.8 GeV center of mass energy
J. Burmester L. Criegee H.C. Dehne K. Derikum R. Devenish J.D. Fox G. Franke G. Flügge Ch. Gerke G. Horlitz Th. Kahl G. Knies M. Rössler S. Wolff R. Schmitz T.N. Ranga Swamy U. Timm K. Wacker 《Physics letters. [Part B]》1977,66(4):395-400
Using the solenoidal magnetic detector PLUTO, we have measured the total cross section for e+e? annihilation into hadrons. Results are presented for center of mass energies between 3.6 and 4.8 GeV, and in the regions of the (3.1) and ψ(3.7) resonances. We also present results for the 2 prong cross section in the energy range 3.6 to 4.8 GeV. 相似文献