here, we propose an add-drop and a channel drop filter based on two-dimensional photonic crystal all circular ring resonators. these structures are made of a square lattice of silicon rods with the refractive index n1=3.464 surrounded by air (with refractive index n2=1). the broadest photonic band gap occurs at the filling ratio of r/a = 0.17. two linear defect w1 waveguides couple to the ring....

this paper presents an e-ring shaped printed monopole antenna for uwb applications with dual notched bands performance. in order to generate single frequency band notch function, we applied a u-ring shaped monopole antenna, and by inserting a rectangular ring in the centre of it an e-ring shaped radiating patch created and a dual band-notch function can be achieved. the measured bandwidth of th...

Sequential transformations1 allow the assembly of complex molecules in a simple manner, with a minimum of purification steps, and are accordingly ideal components of elegant and efficient synthetic strategies. In recent years, samarium diiodide2 has evolved as a unique single electron reducing agent that is especially well suited to promote sequential processes that combine radical and anionic ...

In the present work, B-ZSM-5 zeolite membranes were synthesized on porous tubular α-alumina supports by several subsequence in situ crystallization hydrothermal treatments. The TiO2- Bohmite and ɣ- alumina intermediate layers were applied to improve the lattice matching between zeolite layer and the support. The uniform membrane intermediate layers with low permeation resistance were...

a group of regioisomeric 5-oxo-1,4,5,6,7,8 hexahydroquinoline derivatives possessing a cox-2 so2me pharmacophore at the para position of the c-2 or c-4 phenyl ring, in conjunction with a c-4 or c-2 phenyl (4-h) or substituted-phenyl ring (4-f,4-cl,4-br,4-ome,4-me, 4-no2), were designed for evaluation as selective cyclooxygenase-2 (cox-2) inhibitors. these target 5-oxo-1,4,5,6,7,8 hexahydroquino...

A group of regioisomeric 5-oxo-1,4,5,6,7,8 hexahydroquinoline derivatives possessing a COX-2 SO2Me pharmacophore at the para position of the C-2 or C-4 phenyl ring, in conjunction with a C-4 or C-2 phenyl (4-H) or substituted-phenyl ring (4-F,4-Cl,4-Br,4-OMe,4-Me, 4-NO2), were designed for evaluation as selective cyclooxygenase-2 (COX-2) inhibitors. These target 5-oxo-1,4,5,6,7,8 hexahydroquino...

The reverse inter-shaft gas film seal is a path used in the intermediate bearing cavity of an aero-engine, which challenging to implement due its special installation and usage conditions. This paper proposes C/C (Carbon/Carbon) composite cylindrical structure carries out performance simulation analysis based on bidirectional fluid–solid coupling technology. results show that with double-layer ...

Abstract The vortex cavitation technology shows a great development potential for antibiotic wastewater treatment. We have designed novel swirling cavitator tetracycline degradation in aqueous solution. By Computational Fluid Dynamics (CFD) simulation using ANSYS CFX flow field calculation software, it was found that the could form low-pressure area far lower than saturated vapor pressure at ex...

The effect of ring size on the photo-Favorskii induced ring-contraction reaction of the hydroxybenzocycloalkanonyl acetate and mesylate esters (7a-d, 8a-c) has provided new insight into the mechanism of the rearrangement. By monotonically decreasing the ring size in these cyclic derivatives, the increasing ring strain imposed on the formation of the elusive bicyclic spirocyclopropanone 20 resul...

let r be an associative ring with identity, c(r) be the category of com-plexes of r-modules and flat(c(r)) be the class of all at complexes of r-modules. we show that the at cotorsion theory (flat(c(r)); flat(c(r))−)have enough injectives in c(r). as an application, we prove that for each atcomplex f and each complex y of r-modules, exti (f,x)= 0, whenever ris n-perfect and i > n.