The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A.
The synthesis used a convergent approach involving...
Performance-based design has gained interest in recent years among structural designers and researchers. Performance-based design includes selection of appropriate building sites, structural systems and configurations, as well as analytical procedures used in the design process, to confirm that the structure has adequate strength, stiffness and energy dissipation capacity to respond...
A two-dimensional numerical mesoscale model, which ic1udes
radiative and turbulent transfers, has been constructed to study the
formation, development and dissipation of coastal stratus cloud
under an inversion. In the model, the delta-Eddington and emissivity
approximations are used for the solar and thermal radiative
transfers, respectively. K-theory parameterization is adopted...
The relationships between types of wealth components and consumption
expenditures were investigated as a means of better understanding retired
elderly household well-being. Specifically, the concept of mental account was
used to identify the characteristics of different types of wealth components, and
four mental accounts were identified: flow of investment, current...
As microelectronic parts trend smaller so do their solder joints. The surface finish on a copper pad is expected to become a significant part of the total solder joint volume and therefore affect mechanical properties of the smaller solder joints. Two sample geometries and four different surface finishes for tin-silver-copper...
A complete solution, exact to second-order, for wave motion
forced by a hinged-wavemaker of variable-draft is presented. A
solution for a piston type wavemaker is also obtained as a special
case of a hinged-wavemaker with negative infinite draft. The
existing Stokes inviscid theories for mass transport is extended to
include...
Due to its high strength/weight ratio, 7075 aluminum alloy has
been widely used as an aerospace material. However, it has relatively low fatigue strength and low fracture toughness in the T6
condition. Thermomechanical processing, including pre-cyclic loading and stretching at high and ambient temperatures, has been investigated with the aim...