Ball Joint (ball + joint)

Distribution by Scientific Domains


Selected Abstracts


Nanosized Ball Joints Constructed from C60 and Tribenzotriquinacene Sockets: Synthesis, Component Self-Assembly and Structural Investigations

CHEMISTRY - A EUROPEAN JOURNAL, Issue 35 2007
Björn Bredenkötter Dr.
Abstract The formation of supramolecular host,guest complexes of fullerene (C60) and two novel tribenzotriquinacene based hosts (5,a and 5,b) was investigated in solution and in the solid state. Stability constants for 1:1 and 2:1 complexes were obtained from spectroscopic (UV/Vis, 1H,NMR) titration experiments. Association constants of K1=(2908±360),L,mol,1 and K2=(2076±300),L,mol,1 for C60/5,a, and K1=(5608±220),L,mol,1 and K2=(673±160),L,mol,1 for C60/5,b were obtained. Single crystal X-ray structural analysis of compound C60,5,b,3,toluene revealed that a molecule of C60 was located at short van der Waals contact distances in the open pre-organised cavity of the rigid host. The supramolecular complex created resembles an engineered nanosized ball joint and represents the first member for a future nanomechanics construction kit. [source]


Morphology of deltoid origin and end tendons , a generic model

JOURNAL OF ANATOMY, Issue 6 2008
J. N. A. L. Leijnse
Abstract This study provides a model of the complex deltoid origin and end tendons, as a basis for further anatomical, biomechanical and clinical research. Although the deltoid is used in transpositions with upper limb paralysis, its detailed morphology and segmentation has not been object of much study. Morphologically, the deltoid faces two distinct challenges. It closely envelops a ball joint, and it reduces its width over a short distance from a very wide origin along clavicle, acromion and spina scapula, to an insertion as narrow as the humerus. These challenges necessitate specific morphological tendon adaptations. A qualitative model for these tendons is developed by the stepwise transformation of a unipennate muscle model into a functional deltoid muscle. Each step is the solution to one of the mentioned morphological challenges. The final model is of an end tendon consisting of a continuous succession of bipennate end tendon blades centrally interspaced by unipennate tendon parts. The origin tendon consists of lamellae that interdigitate with the end tendon blades, creating a natural segmentation. The model is illustrated by qualitative dissection results. In addition, in view of a proliferation of terms found in the literature to describe deltoid tendons, tendon concepts are reviewed and the systematic use of the unique and simple terminology of ,origin and end tendons' is proposed. [source]


Nanosized Ball Joints Constructed from C60 and Tribenzotriquinacene Sockets: Synthesis, Component Self-Assembly and Structural Investigations

CHEMISTRY - A EUROPEAN JOURNAL, Issue 35 2007
Björn Bredenkötter Dr.
Abstract The formation of supramolecular host,guest complexes of fullerene (C60) and two novel tribenzotriquinacene based hosts (5,a and 5,b) was investigated in solution and in the solid state. Stability constants for 1:1 and 2:1 complexes were obtained from spectroscopic (UV/Vis, 1H,NMR) titration experiments. Association constants of K1=(2908±360),L,mol,1 and K2=(2076±300),L,mol,1 for C60/5,a, and K1=(5608±220),L,mol,1 and K2=(673±160),L,mol,1 for C60/5,b were obtained. Single crystal X-ray structural analysis of compound C60,5,b,3,toluene revealed that a molecule of C60 was located at short van der Waals contact distances in the open pre-organised cavity of the rigid host. The supramolecular complex created resembles an engineered nanosized ball joint and represents the first member for a future nanomechanics construction kit. [source]


Direct meso-scale simulations of fibres in turbulent liquid flow

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010
J. J. Derksen
Abstract A procedure for direct, meso-scale simulations of flexible fibres immersed in liquid flow is introduced. The fibres are composed of chains of spherical particles connected through ball joints with the bending stiffness of the joints as a variable. The motion of the fibres and the liquid is two-way coupled with full resolution of the solid,liquid interface. First the simulation procedure is validated by means of an analytical solution for sphere doublets in zero-Reynolds simple shear flow. Subsequently we use the numerical method to study inertial flows with fibres, more specifically the interaction of a fibre with isotropic turbulence. Une procédure pour des simulations directes à la méso-échelle de fibres souples immergées dans la circulation de liquide est présentée. Les fibres sont composées de chaînes de particules sphériques reliées par des joints à rotule avec la rigidité à la flexion des joints comme variable. Le mouvement des fibres et du liquide est bidirectionnel avec une résolution intégrale de l'interface solide-liquide. D'abord, la procédure de simulation est validée au moyen d'une solution analytique pour les doublets de sphère dans un écoulement de cisaillement simple à nombre de Reynolds nul. Par la suite, nous utilisons la méthode numérique pour étudier les flux inertiels avec les fibres, plus précisément l'interaction d'une fibre avec la turbulence isotrope. [source]