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41.
In this paper, we give a polytopal estimate of Mirkovi?–Vilonen polytopes lying in a Demazure crystal in terms of Minkowski sums of extremal Mirkovi?–Vilonen polytopes. As an immediate consequence of this result, we provide a necessary (but not sufficient) polytopal condition for a Mirkovi?–Vilonen polytope to lie in a Demazure crystal.  相似文献   
42.
rac‐Bis{μ‐trans‐2,2′‐[pentane‐1,5‐diylbis(azanediyl)]ditroponato}dipalladium(II), [Pd2(C19H20N2O2)2], has been synthesized and fully characterized using single‐crystal X‐ray diffraction, 1H NMR, FT–IR and mass spectroscopy. The trans coordination, vaulted structure and anti conformation have been unequivocally established from the X‐ray diffraction studies. This is the first example of a bis(aminotroponato)palladium complex. In the crystalline state, the molecule has twofold symmetry and each molecular unit undergoes intermolecular offset π‐stacking of the tropone rings to afford heterochiral interpenetrating dimers that are aligned in a lamellar manner with a herringbone packing motif.  相似文献   
43.
Anion‐responsive π‐conjugated compounds having chiral alkyl chains were synthesized. Circular dichroism (CD) and circularly polarized luminescence (CPL) were observed in the solution‐state assemblies of the chiral anion receptors and those of their anion complexes as salts of a planar triazatriangulenium cation. The CD and CPL spectral patterns of the ion‐pair‐based assemblies were completely opposite to those of the anion‐free assemblies, and this suggests that anion binding and subsequent ion pairing change the chirality of the assembly modes.  相似文献   
44.
1,3-Diarylpropenes 9 having a 1,3-dialkoxy-2-methylpropan-2-yl group were designed as tethering monomers for folded H-stacking polymers, and were readily synthesized from 2-ethoxymethylidene malonate in four- or five-steps, including a facile sequential addition–elimination–addition reaction of benzyl zinc reagents. The preference for the closed (stacked) conformation in the resulting 2-substituted 1,3-diarylpropanes 9 was evaluated using MM2 calculations, 1H NMR analyses, and fluorescence measurements. Copolymerization of the resulting monomers 9 with compounds containing π-units provided polymers with blue-shifted UV-absorptions both in solution and as films, compared with that of a model compound containing a single π-unit. This optical property is unique to H-aggregated π-units.  相似文献   
45.
α-Trifluoromethyl chalcones were prepared and evaluated for their antiproliferative activities against androgen-independent prostate cancer cell lines as well as five additional types of human tumor cell lines. The most potent chalcone 5 showed superior antitumor activity in vivo with both oral and intraperitoneal administration at 3 mg/kg. Cell-based mechanism of action studies demonstrated that 5 induced cell accumulation at sub-G1 and G2/M phases without interfering with microtubule polymerization. Furthermore, several cancer cell growth-related proteins were identified by using chalcone 5 as a bait for the affinity purification of binding proteins.  相似文献   
46.
Molecular functions depend on conformations and motions of the corresponding molecular species. An air–water interface is a suitable asymmetric field for the control of molecular conformations and motions under a small applied force. In this work, double‐paddled binuclear PtII complexes containing pyrazole rings linked by alkyl spacers were synthesized and their orientations and emission properties dynamically manipulated at the air–water interface. The complexes emerge from water with concurrent variation of interface orientation of the planes of the PtII complexes from perpendicular to parallel during mechanical compression suggesting a unique ‘submarine emission‘. Phosphorescence of the complexes is quenched at the air–water interface prior to monolayer formation with intensities subsequently rapidly increasing during monolayer compression. These results indicate that asymmetric reactions and motions might be controlled by applying mechanical force at the air–water interface.  相似文献   
47.
48.
The geophysical quantitative excitation on seasonal polar wobble of Earth Rotation has not been well achieved so far. The atmospheric, hydrologic and oceanic angular momentum variations are investigated from monthly values simulated by a coupled ocean-atmosphere general circulation model. The simulated equatorial AAM functions agree well with that from the JMA operational analysis in 90°:E direction, but disagree along Greenwich meridian. As for the annual cycle, not only the hydrologic and oceanic excitations partly match the residuals between geodetic functions of polar wobble and JMA AAM functions, but also the combinations with NCEP and JMA analysis AAM functions are better than those estimated from NCAR-CSM1 climate model.  相似文献   
49.
Evolution of the lower-hybrid(LH)-driven current profile was measured during the formation of an internal transport barrier (ITB) in a reversed magnetic shear discharge. As the ITB developed, the initially centrally peaked LH-driven current profile gradually turned hollow and was sometimes accompanied by an off-axis peak in the electron temperature profile. These observations indicate the concentration of LH power deposition to the ITB for this case as a result of nonlinear coupling between the LH waves and the target plasma.  相似文献   
50.
Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.  相似文献   
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