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Huang GS Miller DH Pavlunin V Sanghi B Shipsey IP Adams GS Cravey M Cummings JP Danko I Napolitano J He Q Muramatsu H Park CS Thorndike EH Coan TE Gao YS Liu F Artuso M Boulahouache C Blusk S Butt J Dorjkhaidav O Li J Menaa N Mountain R Nandakumar R Randrianarivony K Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Briere RA Chen GP Chen J Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Crede V 《Physical review letters》2006,96(3):032003
Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present searches for 25 charmless decay modes of the psi(3770), mostly multibody final states. No evidence for charmless decays is found. 相似文献
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The first all‐solid‐contact paper‐based single‐use polyion‐sensitive ion‐selective electrodes (ISEs) are described. These polyion‐sensitive ISEs are fabricated using cellulose filter paper coated with a carbon ink conductive layer. A polyanion sensing membrane is cast on a section of the coated paper and the sensor is insulated, resulting in a disposable, single‐use device. Various polyanions are shown to yield large negative potentiometric responses when using these disposable devices for direct polyanion detection. These new sensors are further demonstrated to be useful in indirect polycation detection when polycations (i. e., polyquaterniums (PQs)) are titrated with polyanionic dextran sulfate (DS). Titrations monitored using these paper‐based, all‐solid‐contact devices yield endpoints proportional to the given PQ concentration present in the test sample. 相似文献
167.
Simultaneous detection of ultraviolet and infrared radiation in a single GaN/GaAlN heterojunction 总被引:1,自引:0,他引:1
Jayasinghe RC Ariyawansa G Dietz N Perera AG Matsik SG Yu HB Ferguson IT Bezinger A Laframboise SR Buchanan M Liu HC 《Optics letters》2008,33(21):2422-2424
Results are presented for a dual-band detector that simultaneously detects UV radiation in the 250-360 nm and IR radiation in the 5-14 microm regions with near zero spectral cross talk. In this detector having separate UV- and IR-active regions with three contacts (one common contact for both regions) allows the separation of the UV and IR generated photocurrent components, identifying the relative strength of each component. This will be an important development in UV-IR dual-band applications such as fire-flame detection, solar astronomy, and military sensing, eliminating the difficulties of employing several individual detectors with separate electronics-cooling mechanisms. 相似文献
168.
Jillian S. K. Clark Michael J. Ferguson Robert McDonald Mark Stradiotto 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6457-6461
Base‐metal catalysts capable of enabling the assembly of heteroatom‐dense molecules by cross‐coupling of primary heteroarylamines and (hetero)aryl chlorides, while sought‐after given the ubiquity of unsymmetrical di(hetero)arylamino fragments in pharmacophores, are unknown. Herein, we disclose the new “double cage” bisphosphine PAd2‐DalPhos ( L2 ). The derived air‐stable NiII pre‐catalyst C2 functions well at low loadings in challenging test C?N cross‐couplings with established substrates, and facilitates the first Ni‐catalyzed C?N cross‐couplings of primary five‐ or six‐membered ring heteroarylamines and activated (hetero)aryl chlorides, with synthetically useful scope that is competitive with Pd catalysis. 相似文献
169.
Summary 1,2-Cycloheptanedionedioxime (heptoxime), previously reported as a water-soluble gravimetric reagent for nickel, has been applied succesfully to the micro-gravimetric determination of this ion. The procedure, modified from the macro-determination, consists of precipitating nickelheptoxime in a micro-filter beaker and weighing the precipitate after drying at 110–120° C. The commonly encountered cations and metallic ions do not interfere or may be masked by complexing agents. The method has been tested on standard nickel solutions and standard steel samples.
Zusammenfassung Über die Eignung des 1,2-Cycloheptandiondioxims (Heptoxim) als wasserlösliches Reagens für die gravimetrische Bestimmung von Nickel wurde in einer früheren Arbeit berichtet. Nun wird gezeigt, daß es sich auch für die Mikrobestimmung des Nickels eignet. Das Nickelheptoxim wird in einem Filterbecher gefällt und nach Trocknen bei 110 bis 120° C gewogen. Die gewöhnlich das Nickel begleitenden Metalle hindern die Bestimmung entweder nicht oder können durch Überführung in geeignete Komplexe zufriedenstellend maskiert werden. Das Mikroverfahren wurde an Nickellösungen bekannten Gehaltes und an Stahlproben des National Bureau of Standards geprüft.
Résumé On a rapporté dans un travail précédent, la possibilité d'emploi de la cyclo-1,2 heptanedionedioxime (heptoxime) comme réactif hydrosoluble pour le dosage gravimétrique du nickel. On a montré maintenant qu'elle est convenable pour le microdosage du nickel. L'heptoximate de nickel est précipité au bécher-filtre et pesé après séchage à 110–120°. Les métaux qui accompagnent habituellement le nickel, ou bien ne gênent pas ou bien peuvent être masqués d'une façon satisfaisante. Le procédé microchimique a été essayé sur des solutions de nickel de titre connu ou sur des échantillons d'acier du National Bureau of Standards.相似文献
170.
Polymethoxyflavones (PMFs), which exist exclusively in the citrus genus, have biological activities including anti-inflammatory, anticarcinogenic, and antiatherogenic properties. A validated RPLC method was developed for quantitative analysis of six major PMFs, namely nobiletin, tangeretin, sinensetin, 5,6,7,4'-tetramethoxyflavone, 3,5,6,7,3',4'-hexamethoxyflavone, and 3,5,6,7,8,3',4'-heptamethoxyflavone. The polar embedded LC stationary phase was able to fully resolve the six analogues. The developed method was fully validated in terms of linearity, accuracy, precision, sensitivity, and system suitability. The LOD of the method was calculated as 0.15 microg/mL and the recovery rate was between 97.0 and 105.1%. This analytical method was successfully applied to quantify the individual PMFs in four commercially available citrus peel extracts (CPEs). Each extract shows significant difference in the PMF composition and concentration. This method may provide a simple, rapid, and reliable tool to help reveal the correlation between the bioactivity of the PMF extracts and the individual PMF content. 相似文献