منابع مشابه
The unit sum number of Baer rings
In this paper we prove that each element of any regular Baer ring is a sum of two units if no factor ring of R is isomorphic to Z_2 and we characterize regular Baer rings with unit sum numbers $omega$ and $infty$. Then as an application, we discuss the unit sum number of some classes of group rings.
متن کاملThe unit sum number of discrete modules
In this paper, we show that every element of a discrete module is a sum of two units if and only if its endomorphism ring has no factor ring isomorphic to $Z_{2}$. We also characterize unit sum number equal to two for the endomorphism ring of quasi-discrete modules with finite exchange property.
متن کاملA novel method of determining the number of macromolecules per asymmetric unit from accurate crystal-volume measurements.
Knowledge of the number of macromolecules per crystallographic asymmetric unit is frequently useful in the determination of crystal structures. A method has been developed to establish this number directly from measurements of the volume and macromolecular contents of a crystal. The volume of a crystal is determined by measuring the volume of solvent that it displaces in a fine capillary tube. ...
متن کاملHow much biomass do plant communities pack per unit volume?
Aboveground production in terrestrial plant communities is commonly expressed in amount of carbon, or biomass, per unit surface. Alternatively, expressing production per unit volume allows the comparison of communities by their fundamental capacities in packing carbon. In this work we reanalyzed published data from more than 900 plant communities across nine ecosystems to show that standing dry...
متن کاملActivity per unit volume: a pitfall in predicting size.
TO THE EDITOR: A number of texts and articles indicate that dilatation of the hepatobiliary ducts may be suggested from findings on the HIDA study. This should be tempered by the well-known fact that an increase in radioactivity per unit volume in an object makes the image of an object appear larger (1). When there is stasis in the hepatobiliary tree, not necessarily accompanied by dilatation t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1946
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/106.2.121