A method of calculating the normal vibrations of polymer molecules
is presented in detail. The method is based on that used by
Schachtschneider and Snyder in their analysis of polypropylene but
has not heretofore been published. The factoring of the infinite matrix
and reduction to the coordinates of the unit...
The velocity of sound in gases was measured, using an ultrasonic
wave train as a diffraction grating. The fundamental problems
involved in the optical technique are discussed. An apparatus utilizing
an objective lens of focal length 1.5 m and aperture f/20 was constructed
and used at an ultrasonic frequency close...
Metal-oxo clusters can be described as soluble pieces of metal-oxide frameworks. Currently, metal-oxo clusters are being considered as solution-based precursors for extreme ultraviolet (EUV, 13.5 nm) photoresist materials, which are a crucial component in the fabrication of microelectronic devices. Two different photoresist precursor systems have been investigated – alkyltin clusters...
Traditional approaches for the direct preparation of alkenes are unable to fully control either the stereochemical configuration of the carbon-carbon double bond or else the regiochemistry of the substituents surrounding it. The recently introduced concept of carbenoid eliminative cross-coupling (CEXC) offers a remedy to these deficiencies by providing for a...
The use of an adjacency matrix to determine distant (not maximal or
minimal) subgroup and supergroup relationships between crystallographic spacegroup
types is described. Full lists of space-group types that are supergroups and
subgroups for every space-group type were compiled. A list of the space-group
types connected to each space-group type...
Inorganic structures play an important role in materials due to their versatility and diversity. A complete understanding of the structure of a material is vital to enhance the creation of new materials that fill voids in research. The rational design of these compounds is driven by the exploitation of structure-property...