The sterically encumbered pyrrolyl KPyr(tBu2) (1-K, Pyr(tBu2) = 2,5-(Me3C)2C4H2N) reacts with PCl3, (iPr)2PCl and Ph2PCl exclusively at the C3-position to yield a series of phosphine-substituted pyrroles HPyr(tBu2R) (R = PCl2 (2-H), (iPr)2P (4-H) and Ph2P (5-H)). Pyrrole 2-H can further be functionalized with MeLi (3 equiv.) to yield LiPyr(tBu2PMe2) (3-Li). The coordination chemistry of these p...

Application of water stress to isolated spinach (Spinacia oleracea) chloroplasts by redutcion of the osmotic potentials of CO(2) fixation media below -6 to -8 bars resulted in decreased rates of fixation regardless of solute composition. A decrease in CO(2) fixation rate of isolated chloroplasts was also found when leaves were dehydrated in air prior to chloroplast isolation. An inverse respons...

This paper presents the fomulation of the inverse kinematics and dvnamics of the1 3-RRS parallel platform with three degrees of freedom. For inverse kinematics, The position analysis is f irs f ly performed. Then the differential motion constraint vquations of the movable platform are established, based on which the velocity and acceleration formulae of leg actuators are derived. In inverse dyn...

Despite the huge progress made in interactive physics-based mesh deformation, manipulating a geometrically complex mesh or posing a detailed character is still a tedious and time-consuming task. Example-driven methods significantly simplify the modeling process by incorporating structural or anatomical knowledge learned from example poses. However, these approaches yield counter-intuitive, non-...

5.1 ROOT MOTION .....................................................................................................................................................4 5.2 KINEMATIC CONSTRAINTS....................................................................................................................................5 5.3 MOTION CYCLIFICATION .................................................

The present paper studies Plücker coordinates for line elements in Euclidean three-space. The well known relation between line geometry and kinematics is generalized to equiform motions and the geometry of line elements. We consider bundles and linear complexes of line elements and survey their properties. MSC 2000: 51M30, 53A17

After writing programs for a production robot, an operator must manually teach hundreds or thousands of poses. Teaching poses is extremely time consuming and, unfortunately, periodic reteaching is necessary. The need to reteach is commonly due to: wear, repair, slight movements of workpieces, or replacement of the robot and its tools. Our experience has shown that conventional methods of adjust...