Fossil Hystrichospheres concentrated by Sieving Techniques

Determination by Analytical Sieving

ow that some of the general precepts of particle size and shape have been outlined (1) and the all-important topic of powder sampling has been addressed (2), it is appropriate to move into a discussion of the experimental methods used to deduce information about particle size. Analytical sieving is one of the most conceptually simple methods for deducing the particle-size distribution of a powd...

Isolation and Enrichment of Glomeruli Using Sieving Techniques

Block Sieving Algorithms Block Sieving Algorithms

Quite similiar to the Sieve of Erastosthenes, the best-known general algorithms for fac-toring large numbers today are memory-bounded processes. We develop three variations of the sieving phase and discuss them in detail. The fastest modiication is tailored to RISC processors and therefore especially suited for modern workstations and massively parallel supercomputers. For a 116 decimal digit c...

Sieving the Positive Integers by Small Primes

Let Q be a set of primes tha t has relative density 6 among the primes, and let 4 (x,y, Q ) be the number of positive integers 5 x tha t have no prime factor 5 y from the set Q. Standard sieve methods do not seem to give an asymptotic formula for 4 (x,y , Q ) in the case tha t 5 6 < 1. We use a method of Hildebrand to prove that as x -+ w, where u = !S2 and f ( u ) is defined by log Y This may ...

Sieving the Positive Integers by Large Primes

Let Q be a set of primes having relative density 6 among the primes, with 0~6 < 1, and let $(x. y. Q) be the number of positive integers <x that have no prime factors from Q exceeding y. We prove that if y-t cc, then r&x, y, Q) w xp6(u), where u = (log x)/(log y), and ps is the continuous solution of the differential delay equation up&(u) = -6p,(u 1 ), p&(u) = 1, 0 < I( < 1. This generalizes wo...