A series of 8 new complexes of titanium and zirconium with diamido ligands bearing an ethylene and propylene bridge between the two amido groups were synthesized and tested for ethylene polymerization. Titanium complexes bearing an ethylene bridge between the two amido groups showed higher activities than the derivatives with a propylene bridge. In the case of the zirconium complexes, the p...

We consider the problem of finding an orientation with minimum diameter of a connected bridgeless graph. Fomin et. al. [7] discovered a relation between the minimum oriented diameter an the size of a minimal dominating set. We improve their upper bound.

We examine and compare several different classes of “balanced” block codes over q-ary alphabets, namely symbolbalanced (SB) codes, charge-balanced (CB) codes, and polaritybalanced (PB) codes. Known results on the maximum size and asymptotic minimal redundancy of SB and CB codes are reviewed. We then determine the maximum size and asymptotic minimal redundancy of PB codes and of codes which are ...

Irregularities in bridge pier stiffness concentrate the ductility demand on short piers; while not operating on the longer and more flexible ones. The existence of non-uniform, ductility demand distribution in bridges significantly influences seismic response. As such, this paper proposes a new approach for balancing the ductility demand in irregular bridges by utilizing shape memory alloys (SM...

Highway bridges are frequently constructed as simple span structures with steel or concrete girders and a cast-in-place concrete deck, spanning from one pier to another. At each end of the simple span deck, a joint is provided for deck movement due to temperature, shrinkage, and creep. Bridge deck joints are expensive and pose many problems with regard to bridge maintenance. Elimination of deck...

local scouring around bridge piers is a natural phenomenon caused by the erosive process of flowing stream on alluvial beds. the 3d flow field around bridge piers interacting with the bed materials increases complexity of local scour process. the local scour depth develops in accelerated flows and if it is not predicted correctly, the bottom level of local scour hole will exceed the original le...

abstract background: the loop colostomy is one of the most popular techniques used as a protective maneuver for a distal anastomosis and/or temporary fecal diversion. we are introducing the use of a full thickness skin bridge under the large bowel instead of a glass rod which alleviates problems such as protrusion of the large bowel, retraction of the bowel into the abdomen after removing the r...

The folding and assembly of sequence-defined polymers into precisely ordered nanostructures promises a class of well-defined biomimetic architectures with specific function. Amphiphilic diblock copolymers are known to self-assemble in water to form a variety of nanostructured morphologies including spheres, disks, cylinders, and vesicles. In all of these cases, the predominant driving force for...