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71.
Herpin TF Morton GC Dunn AK Fillon C Menard PR Tang SY Salvino JM Labaudinière RF 《Molecular diversity》1998,4(4):221-232
A Lead Discovery Library ofpiperazine-2-carboxamide derivatives was produced forgeneral screening. This paper discloses two novelsolid phase synthetic routes used to produce 15 000single compounds via the Irori directed sortingtechnique. Computational methods such as reagentclustering and library profiling were used to maximizereagent diversity and optimize pharmacokineticparameters. The results of a four center pharmacophoreanalysis revealed the added diversity gained by usingtwo independent synthetic routes. 相似文献
72.
Morelos A Albuquerque IF Bondar NF Carrigan R Chen D Cooper PS Lisheng D Denisov AS Dobrovolsky AV Dubbs T Endler AM Escobar CO Foucher M Golovtsov VL Gottschalk H Gouffon P Grachev VT Khanzadeev AV Kubantsev MA Kuropatkin NP Lach J Lang Pengfei Lebedenko VN Li Chengze Li Yunshan Luksys M Mahon JR McCliment E Newsom C Pommot Maia MC Samsonov VM Schegelsky VA Shi Huanzhang Smith VJ Fukun T Terentyev NK Timm S Tkatch II Uvarov LN Vorobyov AA Yan Jie Wenheng Z Zheng Shuchen Zhong Yuanyuan 《Physical review D: Particles and fields》1995,52(7):3777-3780
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The synthesis and characterization for trifluoromethanesulfonate (triflate) salts of the first definitive examples of cyclotriphosphinophosphonium and cyclodiphosphinophosphonium cations are described, representing new prototypical frameworks in the rational and systematic development of catena-phosphorus chemistry. Addition of methyl triflate (MeOTf) or triflic acid (HOTf) to cyclotetraphosphines (tBuP)4 (1a) or (CyP)4 (1b) gives [(tBuP)3PtBuMe][OTf] (2a[OTf]), [(CyP)3PCyMe][OTf] (2b[OTf]), [(tBuP)3PtBuH][OTf] (3a[OTf]), and [(CyP)3PCyH][OTf] (3b[OTf]), respectively. Cyclotriphosphine (tBuP)3 (4a) reacts with HOTF or Me2PCl/Me3SiOTf to give the ring expanded cations 3a[OTf] and [(tBuP)3PMe2][OTf] (5[OTf]), respectively, but reactions with MeOTf and HCl give cyclic diphosphinophosphonium cation [(tBuP)2PtBuMe][OTf] (6a[OTf]) and ring-opened triphosphine HtBuP-PtBu-PtBuCl (7), respectively. The analogous diphosphinophosphonium cation [(CyP)2PCyMe][OTf] (6b[OTf]) is formed along with 2b[OTf] in reactions of MeOTf with (CyP)3 (4b). Compounds 2a[OTf], 2b[OTf], 3a[OTf], 5[OTf], and 6a[OTf] have been crystallographically characterized. 1H NMR spectra of 2a[OTf], 2b[OTf], 5[OTf], and 6a[OTf] demonstrate that 3JPH coupling is only observed for methyl protons if they are in a cis orientation to the lone pairs on the adjacent phosphine sites. 相似文献
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77.
S. I. Andronenko I. Stiharu D. Menard C. Lacroix Sushil K. Misra 《Applied magnetic resonance》2010,38(4):385-402
SiCN magnetic ceramics doped with Fe ions were synthesized at different pyrolysis temperatures in the range from 600 to 1600°C. Several phases of ceramics were detected using the techniques of electron paramagnetic resonance/ferromagnetic resonance, Raman, Fourier-transform infrared and X-ray diffractometry, listed as follows: (a) transformation to the ceramic state from the polymer state, where the Fe ions are in the paramagnetic state, as the temperature is increased from 600 to 800°C; (b) formation of two different Fe species in the range of 950–1150°C: nanocrystalline particles in the ferromagnetic state and Fe ions incorporated into the free-carbon state in the superparamagnetic state; (c) diminution of the free-carbon content above 1150°C, and, as a consequence, diminution of the intensity of the broad Fe signal related to this phase; (d) appearance of a new Fe phase at about 1200°C; (e) disappearance of the ferromagnetic phase at about 1400°C; (f) disappearance of all Fe ions above 1530°C. The samples exhibiting superparamagnetic behavior are potentially useful in developing high-temperature magnetic sensor devices. 相似文献
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Dubbs T Albuquerque IF Bondar NF Carrigan R Chen D Cooper PS Lisheng D Denisov AS Dobrovolsky AV Endler AM Escobar CO Foucher M Golovtsov VL Gottschalk H Gouffon P Grachev VT Khanzadeev AV Kubantsev MA Kuropatkin NP Lach J Pengfei L Chengze L Yunshan L Luksys M Mahon JR McCliment E Morelos A Newsom C Pommot Maia MC Samsonov VM Schegelsky VA Huanzhang S Smith VJ Fukun T Terentyev NK Timm S Tkatch II Uvarov LN Vorobyov AA Jie Y Wenheng Z Shuchen Z Yuanyuan Z 《Physical review letters》1994,72(6):808-811
80.
S. Menard M. Vampouille A. Desfarges-Berthelemot V. Kermene B. Colombeau C. Froehly 《Optics Communications》1999,160(4-6):344-353
We describe the mutual phase-locking of four Nd:YAG beams longitudinally end-pumped by four fiber-coupled diode lasers. Mutual phase-locking is performed by two types of diffractive components located inside a telescopic Fabry–Perot resonator. The control of the phase-locking is shown and the different spatial eigenmodes connected with the pumping geometry in the resonator are theoretically and experimentally studied. 1.2 W is obtained in a single mode stable pattern with 30% optical-to-optical conversion efficiency in the continuous wave regime. 相似文献