Results 201 to 210 of about 22,919 (246)

An Introduction to Sieve Methods and Their Applications

2005
Sieve theory has a rich and romantic history. The ancient question of whether there exist infinitely many twin primes (primes p such that p+2 is also prime), and Goldbach's conjecture that every even number can be written as the sum of two prime numbers, have been two of the problems that have inspired the development of the theory.
Alina Carmen Cojocaru, M. Ram Murty
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Application of the Sieve Method to the Enumeration of Stable Stereo and Position Isomers of a Series of Deoxycyclitols

Journal of Chemical Information and Computer Sciences, 1997
A pattern inventory is developed for the enumeration of stable stereo and position isomers of any series of deoxycyclitols with the formula (CH2)p(CHOH)q where p(CH2) and q(CHOH) groups form a ring system of size n = (p + q). The counting method consists of two steps:  firstly the application of POLYA's counting theorem gives the number of permutation ...
Robert Martin Nemba, Maurice Fah
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Application of the seed-film method for the preparation of structured molecular sieve catalysts

Catalysis Today, 2001
Abstract The seed-film method has been applied for the preparation of various materials of potential interest as structured molecular sieve catalysts. The method has proven to be very flexible and allows for the reproducible preparation of a number of molecular sieve–substrate combinations as well as the control of the materials’ properties of ...
Johan Sterte, Jonas Hedlund, Derek Creaser, Olov Öhrman, Wang Zheng, Magdalena Lassinantti, Qinghua Li, Fredrik Jareman   +7 more
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Silicoaluminophosphate Molecular Sieves SAPO-11 and SAPO-41: Synthesis, Properties, and Applications for Hydroisomerization of C16+ n-Paraffins. Part 2: Current State of Research on Methods to Control the Crystal Morphology, Dispersion, Acidic Properties, Secondary Porous Structure, and Catalytic Properties of SAPO-11 and SAPO-41 in Hydroisomerization of C16+ n-Paraffins (A Review)

Petroleum Chemistry, 2021
The second part of the review presents the results of research on SAPO-11 and SAPO-41 molecular sieves over the last three decades, with particular emphasis on methods to control the acid properties, morphology, and secondary porous characteristics of these molecular sieves, as well as on the catalytic applications of SAPO-11 and SAPO-41 for ...
M. R. Agliullin, B. I. Kutepov, V. A. Ostroumova, A. L. Maximov   +3 more
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Sieve Methods, Exponential Sums, and their Applications in Number Theory

1997
This volume comprises the proceedings of the 1995 Cardiff symposium on sieve methods, exponential sums, and their applications in number theory. Included are contributions from many leading international figures in this area which encompasses the main branches of analytic number theory.
G. R. H. Greaves, G. Harman, M. N. Huxley   +2 more
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ChemInform Abstract: Application of the Seed‐Film Method for the Preparation of Structured Molecular Sieve Catalysts

ChemInform, 2001
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
J. Sterte, J. Hedlund, D. Creaser, O. Ohrman, W. Zheng, M. Lassinantti, Q. Li, F. Jareman   +7 more
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THE 'LARGE SIEVE' METHOD AND ITS APPLICATIONS IN THE THEORY OF NUMBERS

Russian Mathematical Surveys, 1966
CONTENTSNotationIntroduction § 1. The essence of the method. First applications § 2. The probabilistic interpretation of the 'large sieve' § 3. Composite moduli. Application to binary additive problems § 4. The non-vanishing of L-functions near the line σ = 1 § 5.
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ON SIEVE METHODS AND SOME OF THEIR APPLICATIONS

2005
Let \(v_k\) be a positive number such that between \(x - x^{1/v_k}\) and \(x\) for sufficiently large \(x\) there exists an integer with at most \(k\) prime factors. The author proves that \(k = v + w\) where \(v\) \((= v_k)\) is an integer and \(w\) is the least integer satisfying \[ \log [(5v-w)/(w+5)] \leq 1,3259 (w - 0,1665).
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ChemInform Abstract: Application of the Sieve Method to the Enumeration of Stable Stereo and Position Isomers of a Series of Deoxycyclitols.

ChemInform, 1997
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
R. M. NEMBA, M. FAH
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A new photo-sieving approach: quick and effective semi-automated method for gran size counting for gravel beds, and application to a Chilean Patagonia river

2022
<p>Many rivers in Chilean Patagonia are difficult to access, experience high flow variability and frequent sudden floods, which make traditional grain size distribution sampling and analysis extremely challenging. There are several diverse methods and software that attempt to determine grain size using analysis of photographs.
Amantu Jullian, Franco Fortini, Paulo Quezada, Alejandro Dussaillant, Cristian Gonzales, Pedro Chavez   +5 more
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