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Let R = K[x 1, x 2, x 3, x 4] be the polynomial ring over a field of characteristic zero. For the ideal (x1a, x2b, x3c, x4d) ì R{(x_1^a, x_2^b, x_3^c, x_4^d) \subset R}, where at least one of a, b, c and d is equal to two, we prove that its generic initial ideal with respect to the reverse lexicographic order is the almost revlex ideal corresponding to the same Hilbert function.  相似文献   
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In this paper, we investigated photoconductive characteristics of blue‐sensitive organic photoconductive devices with different silole derivatives. A most important finding is that an external quantum efficiency (EQE) increased with decreasing ionization potential of silole derivative. The significant improved EQE can be explained by the dislocation efficiency of photogenerated carriers in the organic layer, which is estimated from the photoluminescence (PL) quantum yield. A maximum EQE of 52% at −26 MV m−1 was obtained by optimizing the molecular structure and the concentration of silole derivative. This value is the highest EQE for the reported solution‐processed blue‐sensitive organic photoconductive device. Another interesting result is that the signal‐to‐noise ratio was drastically improved by doping silole derivative.  相似文献   
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The relationship between the coordination geometry and photophysical properties of trans-bis[(β-iminomethyl)naphthoxy]platinum(II) was investigated both experimentally and theoretically. A series of platinum(II) complexes with differently substituted iminomethyl groups were synthesized, and their photophysical properties were examined in solution, in the crystalline, and in the PMMA film-dispersed state, respectively (PMMA=poly(methyl methacrylate)). These complexes showed structure-dependent emission spectra, in which the color of the luminescence in the crystalline state varied over a range of about 40 nm depending on the specific bowl-shaped molecular structure. The chiral complexes with (R,R)- and (S,S)-configurations were found to have structure-dependent chiroptical properties both in solution and the PMMA film-dispersed state such that the intensity of circular dichroism (CD) and circularly polarized luminescence (CPL) were enhanced with bulky cyclic substituents at the nitrogen atoms. A theoretical study using density functional theory (DFT) and time-dependent (TD)-DFT calculations revealed that the enhancement of chiroptical responses is due to the amplification of the magnetic dipole moment caused by the distortion of the square planar geometry.  相似文献   
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Invited for this month's cover is the group of Shinji Inagaki from Toyota Central R&D Laboratories Inc. and Ken-ichi Fujita from Kyoto University. The image shows iridium complexes immobilized on the channel walls of periodic mesoporous organosilica, which catalyze the dehydrogenation of a methanol–water mixture to produce hydrogen and carbon dioxide. The Full Paper itself is available at 10.1002/cssc.202002557 .  相似文献   
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We designed and synthesized a new and novel octahedral hexamolybdenum(II) cluster bearing terminal pyridine-3-carboxylate (3L) or pyridine-4-carboxylate ligands (4L), [{Mo6Br8}(3L)6]2– (3) or [{Mo6Br8}(4L)6]2– (4), to demonstrate proton-switched emission behaviour of the cluster. X-ray crystal analysis of 4 demonstrated that the O-atom in the carboxylate group of 4L coordinates to each Mo atom in the {Mo6Br8}4+-core, indicating that the N-atom of 4L in 4 is open for protonation. Reflecting such structural characteristics of the cluster, both 3 and 4 showed proton-switched emission behaviour owing to the changes in the electron-donating abilities of the relevant terminal ligands upon protonation to the pyridine N atoms: blue shifts of the emission spectra and increases in the emission lifetimes of the clusters.  相似文献   
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