Anbindung von Fluoreszenzfarbstoffen an plasmachemisch funktionalisierte und Cucurbituril‐modifizierte Oberflächen

Coupling of fluorescence labels to plasma‐chemically functionalized and cucurbituril modified surfaces Plasma polymerized allylamine layers (50 nm thick) were deposited on polypropylene foils. The in this way with amino groups functionalized polymer surface was reacted with fluorophors of xanthene type resulting in surfaces with relatively low fluorescence intensities. To increase the fluorescence of the labelled foils two ways of decoupling of the fluorescence dye molecules from the surface were tested. At first a spacer was introduced by reaction of the primary amino groups with glutaraldehyde followed by reaction of the residual aldehyde group with diaminohexane. The fluorescence of foils produced by subsequent reaction of the spacer bonded amino‐functionalized surface with the fluorescence dyes was compared with that of the directly labelled allylamine layer. As a second method of amplification a suited supramolecular encapsulation molecule the cucurbit[6]uril (CB6) was applied. The CB6 modified and labelled foils showed enhanced fluorescence intensity.     

Blotching in roll coating

After thermoforming, plastic parts are stacked for shipping, and these parts tend to stick together. Called nesting, sheet stock is often first coated with a silicone compound before thermoforming to prevent this. The coating usually consists of a small amount of lubricant dispersed in a majority of carrier fluid, and this fluid must then dry before reaching the sheet winder or else the coating blotches. This coupling of coating and drying to determine when to expect blotching is examined. Roll coating involves a dimensionless group called the elasticity number that governs the thickness of the coating to be dried. The drying section involves the evaporation of the coating carrier fluid, and then diffusion into the dry surrounding atmosphere. When analyzing the drying, a new dimensionless group that governs blotching is discovered, called blotchability. The result of this analysis allows practitioners to determine which operating conditions cause blotching, and how to eliminate it. Roll coating uses a deflecting rubber roll to apply vanishingly thin coatings (≤1 μm), an interesting elastohydrodynamic problem.     

Good clinical practice

Nine new phenylpropanoids (2-7, 10, 12, and 14) and two compounds representing novel structural classes of 7-O-8' and 7-O-8'.8-O-7' lignans (8 and 9, respectively) have been isolated from Illicium verum and their structures established by two-dimensional NMR. Most of these compounds appear to be biogenetically derived from threo-anethole glycol: relative stereochemistries for some members of this series were established by NOESY; absolute stereochemistries of others were determined by formation of Mosher esters.     

Salzschmelzkorrosion gerichtet erstarrter eutektischer CO-Cr-C-Basis Superlegierungen bei hohen Temperaturen

Corrosion of directionally solidified eutectic Co-Cr-C-Superalloys by molton salts at high temperatures The corrosion behaviour of various directionally solidified 73C-class eutectic alloys (Co-Cr₇C₃) and the conventionally cast nickel base alloy IN 738* were investigated using a eutectic sulphate melt (sodium, calcium, and magnesium with 2% sodium chloride). As these materials are designed for high temperature applications, tests were carried out at 900°, 1000°, and 1100°. The additions to 73C were nickel, aluminium, and manganese. Corrosion surface attack for 73C and IN 738 was found to be similar. The grain boundary formation of sulphides and oxides in IN 738 is shown up as a disadvantage when compared with 73C as 73C has no grain boundaries perpendicular to the surface. This could possibly be compensated by directionally solidifying IN 738. A 10% nickel addition to 73C was found to increase the corrosion resistance, a 2% aluminium addition showed a minor improvement, and a 4.7 or 10% manganese addition to 73C to influence the corrosion resistance considerably.     

Concept for on orbit liquid hydrogen test bed

There is growing interest in the utilization of cryogenic propellants for future space missions. The utilization of these propellants for long duration in space presents substantial challenges in fluid management in the low g environment. Lockheed Martin (LM) is developing the concept for a space borne system for demonstration of long term storage, various fluid management tests involving control of tank pressure, location and identification of vapor and liquid phases, venting in low g, mass gauging, and extension of life with cryocoolers and location of liquid for transfer. In addition the concept includes autonomous coupling and hydrogen transfer from tank to tank. The concept is based on a flight qualified flight proven hydrogen Dewar design from a previous program The concept for this system is described.     

Psychology’s role in mathematics and science education.

Improving mathematics and science education in the United States has been a matter of national concern for over half a century. Psychology has a vital role to play in this enterprise. In this article, the authors review the kinds of contributions that psychology can make in four areas: (a) early understanding of mathematics, (b) understanding of science, (c) social and motivational aspects of involvement in mathematics and science, and (d) assessment of learning in mathematics and science. They also examine challenges to psychology’s playing a central and constructive role and make recommendations for overcoming those challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Computational and experimental study of a microwave electromagnetic bandgap structure with waveguiding defect for potential use as a bandpass wireless interconnect

As clock rates continue to rise, problems with signal integrity, cross-coupling, and radiation may render impractical the baseband metallic interconnects presently used in computers. A potential means to address this problem is to use bandpass wireless interconnects operating at millimeter-wave center frequencies. We have conducted experimental and finite-difference time-domain (FDTD) computational studies scaled to a 10 GHz center frequency of single-row and double-row waveguiding defects within an electromagnetic bandgap structure. Our initial experimental results scaled to 10 GHz have verified the feasibility of achieving an approximately 80% bandwidth with excellent stopband, gain flatness, and matching characteristics. When scaled to millimeter-wave center frequencies above 300 GHz, this technology appears feasible of supporting data rates in the hundreds of Gb/s.     

Adherence of Liquid Crystalline TDI-Polyurethanes to Steel

Linear liquid crystalline polyurethane (LC-PU) were synthesized by the reaction of 2,4-toluene diisocyanate (TDI), 4,4'-bis-(6-hydroxyhexoxy)biphenyl (BHHBP), and poly(butylene adipate) (PBA). The BHHBP as mesogenic unit was incorporated into the hard segment formed by the reaction with the TDI. The hard segments are incompatible with the PBA soft segments. The mesomorphic behaviour is influenced by both the soft segment length and the hard segment concentration.

The adhesion of such polyurethanes used as primer in composites based on steel as substrate and alkyd melamine resin as coating is dependent on the polyurethane structure, the thickness of the polyurethane layer and its drying conditions. The highest wet adhesion stability is achieved by the hard-segment-type polyurethane composed of TDI and the mesogenic unity BHHBP. Partial substitution of BHHBP by 2,2-bis-(hydroxymethyl)propionic acid (BHMPA) in this LC polyurethane enhances the effectiveness of the primer.     

A Nonspurious 3-D Vector Discontinuous Galerkin Finite-Element Time-Domain Method

We propose a nonspurious vector discontinuous Galerkin finite-element time-domain (DG-FETD) method for 3-D electromagnetic simulation. To facilitate the implementation of numerical fluxes for domain decomposition, we construct the DG-FETD scheme based on the first-order Maxwell's equations with variables ${bf E}$ and ${bf H}$. The LT/QN and the CT/LN edge elements are employed to represent ${bf E}$ and ${bf H}$, respectively (or vice versa), to suppress spurious modes, and the Riemann solver is utilized as the numerical flux to correct fields on the interfaces between adjacent subdomains. Numerical experiments show the nonspurious property of the proposed method.