We classify the paracontact Riemannian manifolds that their Riemannian curvature satisfies in the certain condition and we show that this classification is hold for the special cases semi-symmetric and locally symmetric spaces. Finally we study paracontact Riemannian manifolds satisfying R(X, ξ).S = 0, where S is the Ricci tensor.

This paper reports on the synthesis and characterisation of polysulfone (PSf) ultrafltration (UF) membranes modifed with carbon coated alumina Ni-doped titanium dioxide (CCA/Ni-TiO2) nanoparticles. The syntheses of the membranes was carried out using the phase inversion process. The ...

Understanding ecological processes is a prerequisite for the management of rangelands; therefore, recognition of the relationship between environmental factors and vegetation is very important. The present research aims to investigate environmental and management factors affecting rangeland vegetation distribution in Saral rangelands of Kurdistan province, Iran, in 2017. Sampling was done...

Background: The high polymorphism in the human leukocyte antigen (HLA) genes can be used as an identity of individuals to compare with other populations. This extreme polymorphism in the HLA system is accountable for the differences in alleles and haplotypes among ethnic groups, populations, and the inhabitants of many regions. Objective: To define the frequency of HLA alleles and haplotypes am...

in this paper, we study a class of finsler metrics which contains the class of p-reducible andgeneral relatively isotropic landsberg metrics, as special cases. we prove that on a compact finsler manifold,this class of metrics is nothing other than randers metrics. finally, we study this class of finsler metrics withscalar flag curvature and find a condition under which these metrics reduce to r...

The performances of the optimized tree-type cylindrical-shaped nanoporous fltering membranes with six or seven branch pores in each pore tree are analytically studied. The radius Rb,1 of the branch pore for fltration is normally on the 1 or 10 nm scales. The larger trunk pore is for ...