Elastic stability of ring and stringer-stiffened cylindrical shells under axial, internal and external pressures is studied using Ritz method. The stiffeners are rings, stringers and their different arrangements at the inner and outer surfaces of the shell. Critical buckling loads are obtained using Ritz method. It has been found that the cylindrical shells with outside rings are more stable th...

The mol-ecule of the title compound, C(8)H(13)NO(6), a sucrose derivative, consists of two fused tetra-hydro-furan rings having the cis arrangement at the ring junctions, giving a V-shaped mol-ecule. An intra-molecular O-H⋯O inter-action occurs. Inter-molecular O-H⋯O hydrogen bonds help to stabilize the crystal structure.

We propose a polynomial time quantum algorithm for solving the discrete logarithm problem in matrices over finite group rings. The hardness of this problem was recently employed in the design of a key-exchange protocol proposed by D. Kahrobaei, C. Koupparis, and V. Shpilrain [4]. Our result implies that the Kahrobaei et al. protocol does not belong to the realm of post-quantum cryptography.

Using the concept of the λ-lattice introduced recently by V. Snášel we define λ-lattices with antitone involutions. For them we establish a correspondence to ring-like structures similarly as it was done for ortholattices and pseudorings, for Boolean algebras and Boolean rings or for lattices with an antitone involution and the so-called Boolean quasirings.

A microporous cadmium metal organic framework is synthesized and structurally characterized. The material possesses a 3-D framework with a 1-D sinusoidal chain and shows high selectivity for CO2 over N2. The selectivity is attributed to CO2 interacting with two phenyl rings of a V-shaped linker as estimated by the in situ XRD-DSC study.

Using the Luthar–Passi method, we investigate the possible orders and partial augmentations of torsion units of the normalized unit group of integral group rings of Conway simple groups Co1, Co2 and Co3. Let U(ZG) be the unit group of the integral group ring ZG of a finite group G, and V (ZG) be its normalized unit group

In this paper, we introduce a class of $J$-quasipolar rings. Let $R$ be a ring with identity. An element $a$ of a ring $R$ is called {it weakly $J$-quasipolar} if there exists $p^2 = pin comm^2(a)$ such that $a + p$ or $a-p$ are contained in $J(R)$ and the ring $R$ is called {it weakly $J$-quasipolar} if every element of $R$ is weakly $J$-quasipolar. We give many characterizations and investiga...

The title mol-ecule, C(14)H(12)N(2)O(2), exhibits a V-shaped conformation with a dihedral angle of 59.69 (3)° between the benzene and pyridine rings. In the crystal, O-H⋯N hydrogen bonds link the mol-ecules into zigzag chains along [010].

We establish some results in the theory of standard bases of differential ideals (also known as differential Gröbner bases) in differential polynomial rings. This work was stimulated by some articles of V. Weispfenning, devoted to the classification of term-orders and parametric Gröbner bases of ideals generated by monomials and binomials.

The title compound, C(33)H(18)F(6), has a V-shaped conjugated subunit. The dihedral angles between the central cyclo-pentene ring and the directly attached benzene rings are 32.7 (2) and 53.7 (2)°, respectively. The fluoro substituents are disordered, the occupancies refined to a 0.675 (2):0.325 (2) ratio.