Search for the rare decays K(L)→π0π0μ+μ- and K(L)→π0π0X0→π0π0μ+μ-

The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)μ(+)μ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-)) < 1.0 × 10(-10) and Br(K(L)→π(0)π(0)μ(+)μ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.     

Instability of a rotating disk with a support under the action of a static in-plane load

Summary Vibrations of a rotating disk with a clamped inner circle, a free outer periphery and an elastic support at one point are analyzed under the action of a static in-plane load. A solution of the equation of motion is described in form of series by orthogonal eigenfunctions of a non-rotating disk with the same boundary conditions. Relations between natural frequencies and angular velocity and then those between regions of instability of vibrations and the magnitude of static load are shown.

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Instabilität einer drehenden Scheibe mit einer Stütze unter der Wirkung einer ebenen statischen Belastung

Übersicht Schwingungen einer drehenden Scheibe mit einem befestigten inneren Umfang, einem freien äußeren Umfang und einer elastischen Stütze in einem Punkt werden unter der Wirkung einer ebenen statischen Belastung analysiert. Eine Lösung der Bewegungsgleichung wird in der Form von Reihen mit orthogonalen Eigenfunktionen einer nicht drehenden Scheibe mit den gleichen Randbedingungen beschrieben. Beziehungen zwischen Eigenfrequenzen und der Drehgeschwindigkeit sowie zwischen instabilen Bereichen und der Größe der statischen Belastung werden gezeigt.

     

Determination of the parity of the neutral pion via its four-electron decay

We present a new determination of the parity of the neutral pion via the double Dalitz decay pi0-->e+e-e+e-. Our sample, which consists of 30,511 candidate decays, was collected from KL-->pi0pi0pi0 decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative pi0 parity and place a limit on scalar contributions to the pi0-->e+e-e+e- decay amplitude of less than 3.3% assuming CPT conservation. The pi0gamma*gamma* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase-space distribution. Additionally, we have measured the branching ratio of this mode to be B(pi0-->e+e-e+e-)=(3.26+/-0.18)x10(-5).     

Capillary zone electrophoretic determination of iodide in seawater using transient isotachophoresis with artificial seawater as the background electrolyte

We describe an application of capillary zone electrophoresis (CZE) with transient isotachophoresis (ITP) as the on-line concentration procedure for the determination of iodide in seawater. The effective mobility of iodide was decreased by the addition of 10 mM cetyltrimethylammonium chloride (CTAC) to an artificial seawater background electrolyte (BGE) so that transient ITP functioned and iodide was separated from other coexisting anions such as bromide, nitrite, and nitrate in seawater samples. After sample injection, 600 mM acetate was separately injected into the capillary as the terminating ion to generate transient ITP. The limit of detection (LOD) for iodide was 3.0 microg/L. The LOD was obtained at a signal-to-noise ratio (S/N) of 3. The values of the relative standard deviation (RSD) of peak area, peak height, and migration time for iodide were 2.9, 2.1, and 0.6%. The proposed method was applied to the determination of iodide in seawater collected around the Osaka Bay. The results obtained by use of the calibration graph were agreed with those obtained by the addition of the standard solutions for iodide.     

Photochemical reactions of high polymers. XIV. Syntheses and photochemical reactions of copolymers bearing O-acyloxime groups

Copolymers bearing pendant O-acyloxime groups were synthesized by two methods: copolymerizations of oxime acrylate (methyl β-naphthyl ketone oxime acrylate or benzophenone oxime acrylate) and styrene, condensation of acrylic acid—styrene copolymer with oximes (benzophenone oxime, p-nitrobenzophenone oxime, methyl β-naphthyl ketone oxime, benzalacetone oxime or 9-fluorenone oxime). The photochemical behavior of the O-acyloxime copolymers changed markedly with the irradiation conditions: irradiation of benzene solutions led to degradation in air and crosslinking under nitrogen, while irradiation of solid films in air resulted in simultaneous degradation and crosslinking. Photolysis of methyl β-naphthyl ketone oxime acetate, a model for the O-acyloxime copolymer, in benzene solution under nitrogen resulted in scission of the N? O bond. The same reaction was observed in the irradiation of the O-acyloxime copolymers. It is suggested that formation of free radicals on the polymer chains via scission of the N? O bond is followed by decarboxylation. In the absence of oxygen, crosslinking of the polymer by recombination of the free radicals competes with degradation via β-scission. In the presence of oxygen, autoxidative degradation predominates.     

Multifunctional photo acid generator for fluorescence imaging based on self-contained photoreaction

We present N-(p-anilinesulfonyloxy)-1,8-naphthalimide (ASNI) as fluorescence imaging material based on a novel fluorescence imaging mechanism. ASNI is composed of two functional moieties in one molecule: an acid-reactive fluorescence probe and a photoacid generator (PAG). When ASNI is photoirradiated, a bond in the PAG moiety breaks and an acid is generated. The fluorescence probe moiety then detects the acid and fluoresces. We call this novel mechanism a self-contained photoreaction (SCP). The photophysical properties and photoreactivity of ASNI were measured and compared with those of a prototype PAG, N-(phenylsulfonyloxy)-1,8-naphthalimide. These were well represented by density functional theory calculations. SCP permits one-step fluorescence imaging without any wet or dry developing process.     

Inkjet-printed paperfluidic immuno-chemical sensing device

This paper reports on an inkjet printing method for the fabrication of lateral flow immunochromatographic devices made from a single piece of filter paper by patterning microfluidic channels and dispensing immunosensing inks, requiring only a single printing apparatus. This “paperfluidic” immunosensing device allows for a less time-consuming and more low-cost fabrication compared with the conventional immunochromatographic strips requiring multiple pads, plastic or nylon backing, and a plastic case. A sandwich immunoreaction was performed on the patterned immunosensing paper device, and the sensitivity of the device was optimized with an IgG model analyte. Inkjet-printed antibodies on the test line and the control line were immobilized by physical adsorption, resulting in a very simple fabrication method applicable for pure cellulose surfaces. The color intensity in the test line and the control line was determined both by naked eye and by means of a color scanner in combination with a simple computer program. With the resulting paperfluidic immunosensing device, human IgG concentrations at least down to 10 μg/l could be detected within 20 min. Additionally, in order to demonstrate the feasibility of a total multianalyte sensing system, a combined immuno-chemical sensing device was also fabricated by patterning an additional microfluidic channel for a chemical assay onto the same paper substrate. This low-cost multianalyte paperfluidic sensing device thus demonstrates the feasibility of simple, portable, and disposable tools for pathogen detection in the field of medical, environmental, and food analyses, possibly resulting in useful devices in remote settings and less-industrialized countries.     

First total synthesis of (+/-)-Linderol A,a tricyclic hexahydrodibenzofuran constituent of Lindera umbellata bark,with potent inhibitory activity on melanin biosynthesis of cultured B-16 melanoma cells

The first total synthesis of (+/-)-Linderol A, a hexahydrodibenzofuran constituent of Lindera umbellata bark, with potent inhibitory activity on the melanin biosynthesis of cultured B-16 melanoma cells, was achieved through 19 steps of reaction in 6.6% overall yield, in which the critical step was a tandem reaction of a 3-ethoxycarbonylcoumarin derivative with dimethylsulfoxonium methylide to yield the 2-ethoxycarbonylcyclopenta[b]benzofuran-3-ol derivative.     

Asymmetric synthesis of anti- and syn-beta-amino alcohols by reductive cross-coupling of transition metal-coordinated planar chiral arylaldehydes with aldimines

Samarium iodide-mediated cross-coupling of N-tosyl ferrocenylideneamine with planar chiral ferrocenecarboxaldehydes or benzaldehyde chromium complexes gave diastereoselectively the corresponding anti-beta-amino alcohol derivatives in good yields, while N-tosyl benzylideneamine produced syn-beta-amino alcohols by coupling with planar chiral arylaldehydes. Dynamic kinetic resolution of a configurationally equilibrated reactive species generated from achiral N-tosyl ferrocenilideneamine and benzylideneamine by reduction with samarium iodide was observed in the cross-coupling with planar chiral arylaldehydes giving both antipodes of beta-amino alcohols depending on the planar chirality. The obtained anti-beta-amino alcohol with the ferrocene ring was utilized as a chiral ligand for catalytic asymmetric reduction of acetophenone.