where two particular combinations of the rate constants for primary nucleation (kn), elongation (k+), and fibril-catalysed secondary nucleation (k2) define much of the macroscopic behaviour; these parameters are related to the rate of formation of new aggregates through primary pathways λ = �2k+knm(0)c and through secondary pathways κ = �2k+k2m(0)2. Indeed, Eq. 1 depends on the rate constants t...

We shall develop here a galois theory for difference equations. In the PicardVessiot galois theory for differential equations, the basic objects of study are the Picard-Vessiot extension of a field and its associated galois group. Recall that a Picard-Vessiot extension of a differential field k is an extension K generated by a fundamental set of solutions of a linear differential equation and h...

This paper proposes a data-driven turbulence model for predicting the mean flow in turbulent circular jets over wide range of Reynolds numbers (Re). The main formulation is adapted from well-known k–ε (where k kinetic energy, and ε dissipation rate) with set Re-dependent variation constants. Tam–Thies correction applied constants optimized using data assimilation based on ensemble Kalman filter...

In this theoretical research, the mechanism of the C2H + C2H2 reaction is studied by high-level quantum-chemical methods and kinetics of the reaction is investigated by statistical rate theories. High-level electronic structure calculation methods including M06-2X, CCSD(T), CBS-Q and G4 methods are employed to explore the doublet potential energy surface of the reaction and compute the molecula...

in this article, we consider the uniqueness of the difference monomials $f^{n}(z)f(z+c)$. suppose that $f(z)$ and $g(z)$ are transcendental meromorphic functions with finite order and $e_k(1, f^{n}(z)f(z+c))=e_k(1, g^{n}(z)g(z+c))$. then we prove that if one of the following holds (i) $n geq 14$ and $kgeq 3$, (ii) $n geq 16$ and $k=2$, (iii) $n geq 22$ and $k=1$, then $f(z)equiv t_1g(z)$ or $f(...

We consider Landau’s type inequalities of the form ‖Aku‖n ≤ Cn,k‖u‖n−k‖Anu‖k, u ∈ D(A), 0 < k < n, where A is the infinitesimal generator of either a strongly continuous semigroup or a strongly continuous cosine function of linear contractions on a Banach space X. The constants Cn,k are computed for n ≤ 6.

There exist constants c k > 0, c k ! 0 as k ! 1, such that every DLL algorithm for the satissability of sets of disjunctions of size k using m variables runs for at least (2 m(1?c k)) steps on some inputs. Our proof is based on proving such a lower bound on the tree-like resolution proofs of generalized Tseitin tautologies.

Our main objective is to study some qualitative behavior of the solutions of the difference equation xn+1 = γxn−k + (axn + bxn−k) / (cxn − dxn−k) , n = 0, 1, 2, ..., where the initial conditions x−k,..., x−1, x0 are arbitrary positive real numbers and the coefficients γ, a, b, c and d are positive constants, while k is a positive integer number.

the kinetics and mechanism of the reaction of 5-nitro-1h-benzo[d] imidazole to produce 6-nitro-1h-benzo[d] imidazole was studied by employing hybrid meta-density functional theory. mpwblk/6-31+g** level calculations were carried out to obtain energies and optimize the geometries of all stationary points along the pes, and determine the harmonic vibrational frequencies. two transition states (ts...

interactions of cationic tetrakis (n,n´,n´´,n´´´-tetramethyltetra-3,4-pyridinoporphyrazinatocobalt(ii) (co(tmtppa)) with synthetic polynucleotides, poly(a-t), poly(g-c) and calf thymus dna have been characterized in 5 mm phosphate buffer, ph 7.2, by optical absorption and fluorescence spectroscopy. the appearance of hypochromicity effect and the red shift in uv-vis spectrum of porphyrazine was ...