Velocity measurement of start-up flow of polymeric solutions in a planar contraction channel

The start-up flow of polymeric solutions in an abrupt contraction channel with a rectangular cross-section was experimentally studied. Aqueous solutions with 0.2 wt% and 1.0 wt% of polyacrylamide were used as test fluids. Temporal changes in velocity were measured with a laser Doppler velocimeter. The velocity overshot just after the onset of the flow. The changes in velocity caused by the rearrangement of the velocity distribution were observed. A three-dimensional flow structure and the development of a vortex region were found near the entrance to the contraction. A decrease in the axial velocity just upstream from the contraction was observed. The velocity profile is related to the three-dimensional nature of the flow and the elongational rheological properties of the test fluid. The experimental results indicate that three-dimensional analysis of viscoelastic flows is required especially for the flow in rectangular channels. Received: 6 July 1998 Accepted: 1 December 1998     

In‐situ Fabrication of Functional Materials inside Porous Fiber using Microwave Selective Heating

We developed a simple fabrication method, which can emplace functional materials inside porous fibers. In contrast to conventional impregnation methods or surface coating, various functions can be included inside of natural or synthetic fibers. This fabrication method has three steps. First, the raw material solution is absorbed to the fiber. Then the fiber is immersed and pressurized in immiscible liquids with the raw material solution. Finally, the functional particles are fabricated in‐situ inside of the fiber by a chemical reaction such as microwave selective heating. As a model reaction, we fabricated silver‐nanoparticle‐containing cotton fiber. The elemental silver was distributed inside of the fiber in a cross‐sectional distribution as confirmed by SEM‐EDS. Furthermore, we fabricated fibers with zeolite particles inside of porous PTFE fibers.     

Comprehensive 3D-RISM analysis of the hydration of small molecule binding sites in ligand-free protein structures

Hydration is a critical factor in the ligand binding process. Herein, to examine the hydration states of ligand binding sites, the three-dimensional distribution function for the water oxygen site, g_O( r ) , is computed for 3,706 ligand-free protein structures based on the corresponding small molecule–protein complexes using the 3D-RISM theory. For crystallographic waters (CWs) close to the ligand, g_O( r ) reveals that several CWs are stabilized by interaction networks formed between the ligand, CW, and protein. Based on the g_O( r ) for the crystallographic binding pose of the ligand, hydrogen bond interactions are dominant in the highly hydrated regions while weak interactions such as CH-O are dominant in the moderately hydrated regions. The polar heteroatoms of the ligand occupy the highly hydrated and moderately hydrated regions in the crystallographic (correct) and wrongly docked (incorrect) poses, respectively. Thus, the g_O( r ) of polar heteroatoms may be used to distinguish the correct binding poses.     

Existence of Tangential Limits for α-Harmonic Functions on Half Spaces

Our aim in this paper is to prove the existence of tangential limits for Poisson integrals of the fractional order of functions in the L ^p Hölder space on half spaces.     

New solanocapsine-type tomato glycoside from ripe fruit of Solanum lycopersicum

A new solanocapsine-type tomato glycoside, a novel and interesting natural steroidal glycoside, was isolated from a mini tomato, Solanum lycopersicum L. The chemical structure of the new minor glycoside, esculeoside B-5 (3), was determined to be (5S,22R,23S,24R,25S)-22,26-epimino-16β,23-epoxy-3β,23,24-trihydroxycholestane 3-O-β-lycotetraoside.     

Four new iridoid glucosides from Ajuga reptans

Four new iridoid glucosides were isolated from the whole plant of Ajuga reptans L. (Labiatae) along with four known iridoid glucosides, one known diterpenoid glycoside, one known aliphatic alcohol glycoside, and three known ecdysteroids. Their chemical structures were determined on the basis of spectroscopic data and chemical evidence. The diterpenoid glycoside exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and H?O? scavenging activities.     

Iterated maximal functions in variable exponent Lebesgue spaces

In this paper we study the iterated Hardy?CLittlewood maximal operator in variable exponent Lebesgue spaces with exponent allowed to reach the value 1. We use modulars where the L ^p(·)-modular is perturbed by a logarithmic-type function, and the results hold also in the more general context of such Musielak?COrlicz spaces.     

A Montel Type Result for Super-Polyharmonic Functions on R<Superscript><Emphasis Type="Italic">N</Emphasis></Superscript>

Our aim in this paper is to discuss a Montel type result for a family F{\mathcal F} of super-polyharmonic functions on R ^N . We give a condition on spherical means to assure that F{\mathcal F} contains a sequence converging outside a set of capacity zero.     

Sobolev's inequality for Riesz potentials of functions in Morrey spaces of integral form

Morrey spaces have become a good tool for the study of existence and regularity of solutions of partial differential equations. Our aim in this paper is to give Sobolev's inequality for Riesz potentials of functions in Morrey spaces (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)