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945.
An -factor pure product is a polynomial which can be expressed in the form for some natural numbers . We define the norm of a polynomial to be the sum of the absolute values of the coefficients. It is known that every -factor pure product has norm at least . We describe three algorithms for determining the least norm an -factor pure product can have. We report results of our computations using one of these algorithms which include the result that every -factor pure product has norm strictly greater than if is , , , or .

  相似文献   

946.
We build generalizations of the Grassmann algebras from a few following simple assumptions: the algebras are graded, maximally symmetric and contain an ordinary Grassmann algebra as a subalgebra. These algebras are graded by and display surprising properties that indicate their possible application to the modeling of quark fields. We build the generalized supersymmetry generators based on these algebras and their derivation operators. These generators are cubic roots of the usual supersymmetry generators.  相似文献   
947.
The nucleus 73 Se was studied by the reaction 51 V(28 Si,αpn)73 Se. The level scheme extended upto $\frac{{41}} {2}\bar h $ in both +ve and ?ve parity bands with 10 new transitions placed in the level scheme. Lifetimes of 17 high spin states measured by DSAM. The transitional quadrupole moment is found to drop down after the band crossing suggesting a less deformed configuration. At the band crossing region, Q t increases suddenly in both +ve and ?ve parity bands. It is argued that the +ve parity band is a decoupled band.  相似文献   
948.
Sonoluminescence (SL) refers to the generation of light through the energetic pulsations of acoustic cavitation bubbles in a liquid. For years, SL was observed primarily in cavitation fields. These bubbles are believed by many to undergo near-adiabatic compression, resulting in the heating of the bubble contents and the subsequent emission of light. Recently, researchers have discovered a 'new' form of sonoluminescence in which light is observed to emanate from a single bubble undergoing very large volume excursions. The mechanism for light production is unknown, but many believe it is due to a rapid heating of the central core by an imploding shock wave. Based in part on the emission time scales, there is a common belief that the two forms of SL are quite distinct. We address this issue by comparing the two phenomena with regards to their light-flash durations and emission spectra--leading to some surprising differences and similarities.  相似文献   
949.
Arthrichitin (1), C(33)H(46)N(4)O(9), is a new cell wall active depsipeptide isolated from the fermentation broth of Arthrinium phaeospermum (HIL Y-903022). Its structure was elucidated on the basis of spectroscopic and chemical degradation studies. Arthrichitin consists of serine, beta-keto tryptophan, glutamic acid, and 2,4-dimethyl-3-hydroxydodecanoic acid units.  相似文献   
950.
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