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121.
This paper describes a method for the efficient determination of maximally allowed shovel forces for a heavy-load faceshovel excavator through its workspace, based on the concept of “kinematical transformers”. In this concept, each multibody loop is regarded as a transmission element coupled by linear equations with the other multibody loops, allowing an efficient detection of closed-form kinematical solutions. Additionally, the method uses a graphical optimization approach to find the maximal digging forces for given positions of the shovel. An application-specific code has been realized using a combination of the object-oriented multibody library MBILE and symbolical equations. The method is applied to existing heavy-load excavators, showing that by the use of symbolical kinematics, the computational effort can be reduced substantially. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
122.
123.
Ohne ZusammenfassungAm Schlusse meiner Ausführung angelangt, bitte ich noch meinen verehrten Lehrer Hofrat Adolf Lieben, meinen ergebensten Dank entgegenzunehmen für die freundliche Unterstützung, die er meiner Arbeit durch seine Ratschläge angedeihen ließ, und für das Interesse, das er ihr entgegenbrachte.Auch danke ich hier dem Herrn Privatdozenten Dr. C. Pomeranz für seine freundliche Unterstützung. 相似文献
124.
Alois Smolka 《Monatshefte für Chemie / Chemical Monthly》1887,8(1):379-390
Ohne Zusammenfassung 相似文献
125.
126.
127.
Pavel Svoboda Pavel Javorský Fuminori Honda Vladimír Sechovský Alois A. Menovsky 《Central European Journal of Physics》2004,2(2):397-418
The tetragonal compound UNi2Si2 exhibits in zero magnetic field three different antiferromagnetic phases belowT
N
=124 K. They are formed by ferromagnetic basal planes, which are antiferromagnetically coupled along thec-axis with the propagation vectorq=(0, 0, q
z
). Two additional order-order magnetic phase transitions are observed below T
N
, namely atT
1=108 K and T
2=40 K in zero magnetic field. All three phases exhibit strong uniaxial anisotropy confining the U moments to a direction parallel
to the c-axis. UNi2Si2 single crystals were studied in detail by measuring bulk thermodynamic properties, such as thermal expansion, resistivity,
susceptibility, and specific heat. A microscopic study using neutron diffraction was performed in magnetic fields up to 14.5
T parallel to the c-axis, and a complex magnetic phase diagram has been determined. Here, we present the analysis of specific-heat data measured
in magnetic fields up to 14 T compared with the results of the neutron-diffraction study and with other thermodynamic properties
of UNi2Si2. 相似文献
128.
Dr. Alexander G. Tskhovrebov Dr. Richard Goddard Prof. Alois Fürstner 《Angewandte Chemie (International ed. in English)》2018,57(27):8089-8094
Two highly labile silver carbene cluster complexes are described, which are unique in that they mark the transition point at which the carbene center transmutes from a fairly common NHC‐like nucleophilic behavior to an electrophilic character befitting reactive silver carbene intermediates of relevance in various catalytic transformations. This amphoteric character is the distinguishing attribute of a μ‐bridged donor/donor carbene entity that connects two silver atoms of triangular or tetrahedral metallic core units. 相似文献
129.
Alois Würger 《Zeitschrift für Physik B Condensed Matter》1995,98(4):561-573
The dynamics of strongly interacting two-level tunnelling defects in mixed crystals as KCl: Li is investigated in the framework of Mori's projection method. Applying a mode-coupling scheme on the memory functions and performing the average over the random defect configuration in a mean-field type approximation, the ensueing self-consistent equations can be solved analytically. At low concentration this solution coincides with the exact dynamics of the pair model, whereas for higher concentration the motional spectrum shows several novel features. In particular we find a strong relaxation peak and a characteristic two-peak structure for the density of states; there is an additional feature at energies far below the bare tunnelling amplitude which accounts well for several experiments indicating the existence of such low-energy states. 相似文献
130.
Ferdinand Belaj Christoph Kratky Edgar Nachbaur Alois Popitsch 《Monatshefte für Chemie / Chemical Monthly》1987,118(3):349-354
An X-ray crystal structure analysis of colourless Ag3SO3N · 3NH3 · 2H2O was carried out at room temperature:M=504.79, orthorhombic, P212121,a=6.275 (1) Å,b=11.826 (2) Å,c=14.299 (12) Å,V=1061.10 Å3,Z=4,d
x=3.160 Mgm–3,F(000)=940, Mo K, =0.71069 Å (graphite monochromator), =5.60 mm–1,R=4.71%,R
w=4.96% (982 reflections, 120 parameters). The structure consists of Ag ribbons; each Ag atom is linearly co-ordinated to two N atoms with distances corresponding to covalent Ag-N bonds; no Ag-O coordination is observed; the N atom of the SO3N group is surrounded by three Ag atoms; compared to amidosulfuric acid, the SO3N group shows significant deformation. 相似文献