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61.
Bellotti R Cafagna F Caliccio M De Cataldo G De Marzo C Erriquez O Favuzzi C Giglietto N Nappi E Spinelli P Cecchini S Fabbri M Giacomelli G Mandrioli G Matteuzzi P Pal B Patrizii L Predieri F Sanzani GL Serra P Spurio M Ahlen S Ficenec D Hazen E Klein S Levin D Marin A Stone JL Sulak LR Worstell W Barish B Coutu S Hong J Liu G Peck C Solie D Steele J Lane C Steinberg R Battistoni G Bilokon H Bloise C Campana P Chiarella V Forti C Grillo A Iarocci E Marini A Patera V Reynoldson J Ronga F 《Physical review D: Particles and fields》1990,42(5):1396-1403
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A series of potassium aryloxides (KOAr) were isolated from the reaction of a potassium amide (KN(SiMe(3))(2)) and the desired substituted phenoxide (oMP, 2-methyl; oPP, 2-iso-propyl; oBP, 2-tert-butyl; DMP, 2,6-di-methyl; DIP, 2,6-di-iso-propyl; DBP, 2,6-di-tert-butyl) in tetrahydrofuran (THF) or pyridine (py) as the following: [([K(mu(4)-oMP)(THF)][K(mu(3)-oMP)])(5)]( infinity ) (1), [[K(6)(eta(6),mu(3)-oMP)(4)(eta(6),mu(4)-oMP)(2)(py)(4)].[K(6)(eta(6),mu(3)-oMP)(6)(eta(6)-py)(4)]]( infinity ) (2), [K(mu(3)-oPP)](4)(THF)(3) (3), [K(4)(eta(6),mu(3)-oPP)(2)(mu(3)-oPP)(2)(py)(3)]( infinity ) (4), [K(mu(3)-oBP)(THF)](6) (5), [K(6)(eta(6),mu(3)-oBP)(2)(mu(3)-oBP)(4)(py)(4)]( infinity ) (6), [K(3)(eta(6),mu(3)-DMP)(2)(mu-DMP)(THF)]( infinity ) (7), [[K(eta(6),mu-DMP)(py)](2)]( infinity ) (8), [K(eta(6),mu-DIP)]( infinity ) (9), [K(eta(6),mu-DBP)]( infinity ) (10). Further exploration of the aryl interactions led to the investigation of the diphenylethoxide (DPE) derivative which was isolated as [K(mu(3)-DPE)(THF)](4) (11) or [K(mu(3)-DPE)(py)](4).py(2) (12) depending on the solvent used. In general, the less sterically demanding ligands (oMP, oPP, oBP, and DMP) were solvated polymeric species; however, increasing the steric bulk (DIP and DBP) led to unsolvated polymers and not discrete molecules. For most of this novel family of compounds, the K atoms were pi-bound to the aryl rings of the neighboring phenoxide derivatives to fill their coordination sites. The synthesss and characterization of these compounds are described in detail. 相似文献
64.
Yue GE Roper MG Jeffery ED Easley CJ Balchunas C Landers JP Ferrance JP 《Lab on a chip》2005,5(6):619-627
In this study a novel glass membrane was prepared for conducting high voltage (HV) to solution in the channel of a microfabricated device for generation of liquid electrospray. Taylor cone formation and mass spectra obtained from this microdevice confirmed the utility of the glass membrane, but voltage conduction through the membrane could not be successfully explained based solely on the conductivity of the glass itself. This novel method for developing a high-voltage interface for microdevices avoids direct metal/liquid contact eliminating bubble formation in the channel due to water hydrolysis on the surface of the metal. Further, this arrangement produces no dead volume as is often found with traditional liquid junctions. At the same time, preliminary investigations into the outlet design of glass microdevices for interfacing with electrospray mass spectrometry, was explored. Both the exit shape and the use of hydrophobic coatings at the channel exit of the microdevice electrospray interface were evaluated using standard proteins with results indicating the utility of this type of design after further optimization. 相似文献
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This paper presents a study of a group of O.R. projects. The major emphasis of the research was on a comparison of both the managers' and the O.R. practitioners' perceptions and attitudes. The results show a large amount of agreement between the two groups, and the main disagreement concerned their confidence in the solution. A principal component analysis of the data followed by an orthogonal rotation produced a set of eight principal factors. These were then used for a regression analysis having implementation and success as dependent variables. The results indicate that major differences are seen in the relationship of the dependents to the factors when analysed separately for managers and practitioners. Most of the variance in the implementation score of practitioners is ‘explained’ by attitudinal variables, but this is not true for managers. Implications of the research for this Churchman/Schainblatt concept of "mutual understanding" are suggested. 相似文献
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A research-oriented gas chromatography—mass spectrometry data system for a quadrupole mass spectrometer has been developed based on a centrally located departmental computer facility. An overview of the hardware and software system is presented, emphasizing the important aspects of on-line computer data acquisition and control and the design philosophy used in the development of the system. The application of the system is demonstrated by the g.c.—m.s. analysis of a mixture of four transition metal β-diketonates (Al, Cr, Rh, and Ru tris-1,1,1-trifluoro-pentane-2,4-dionate). This analysis involved vacuum gas chromatography with a support-coated open tubular column and detection of the eluent by chemical ionization mass spectrometry. The results demonstrate the data system capabilities and indicate the utility of the combined methodologies. 相似文献
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Methods for the preparation of phosphonothioates, phosphonodithioates, phosphorothioates, phosphinothioates and related compounds are reviewed. The application of these compounds as synthetic intermediates is also discussed. 相似文献
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