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Conditions are given for a multiplicative lattice to be a finite Boolean algebra. Multiplicative lattices in which semiprimary elements are primary or in which prime elements are weak meet principal are studied. The lattice of filters of a bounded commutative semilattice are investigated. Finally, we study compactly packed lattices.  相似文献   
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This work synthesized and characterized the NOR-RIB 1:1 (mol–mol) cocrystal. During a study of the reagents, Riboflavin (RIB) melted at 304 °C, which is different from the temperature previously reported in the literature (280–290 °C); therefore, this compound was characterized individually. Subsequently, the cocrystal was synthesized with the active pharmaceutical ingredient (API) norfloxacin (NOR) with the RIB coformer, and the mechanochemical synthesis route was adopted. NOR, RIB, and the cocrystal were characterized by thermogravimetry–differential thermal analysis (TG–DTA), differential scanning calorimetry (DSC), DSC coupled to a microscope (photo-DSC), mid-infrared spectroscopy (MIR), and powder X-ray diffraction. The results of thermal analysis showed that the RIB starts decomposition process (260 °C) and then melts (304 °C). The MIR found that beginning at 295 °C, the RIB passes into the form of a decomposition intermediate; therefore, the melting point observed in the DSC curve is related to this decomposition material. The cocrystal presented thermal stability (200 °C) lower than the API (235 °C) and the coformer (260 °C). The DSC curve did not contain a melting peak. The bands at 1726 cm?1 (C=O of the carboxylic acid) for the NOR, and the band at 3326 cm?1 (stretch O–H), among others, were not visible for the cocrystal in the MIR spectrum, indicating interactions in these regions. The X-ray diffractograms showed a new diffraction pattern, which proved the obtainment of a new phase and cocrystal formation.

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The spin-momentum correlation parameter A(V)(ed) was measured for the 2H-->(e-->,e'p)n reaction for missing momenta up to 350 MeV/c at Q2 = 0.21 (GeV/c)(2) for quasielastic scattering of polarized electrons from vector-polarized deuterium. The data give detailed information about the deuteron spin structure and are in good agreement with the results of microscopic calculations based on realistic nucleon-nucleon potentials and including various spin-dependent reaction mechanism effects. The experiment reveals in a most direct manner the effects of the D state in the deuteron ground-state wave function and shows the importance of isobar configurations for this reaction.  相似文献   
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We report on first measurements with polarized electrons stored in a medium-energy ring and with a polarized internal target. Polarized electrons were injected at 442 MeV (653 MeV), and a partial (full) Siberian snake was employed to preserve the polarization. Longitudinal polarization at the interaction point and polarization lifetime of the stored electrons were determined with laser backscattering. Spin observables were measured for electrodisintegration of polarized 3He, with simultaneous detection of scattered electrons, protons, neutrons, deuterons, and 3He nuclei, over a large phase space.  相似文献   
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Journal of Thermal Analysis and Calorimetry - This work investigates the thermal polymerization process of a methylene diphenyl diisocyanate (MDI) monomer as well as its thermal degradation...  相似文献   
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