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91.
Hidenori Katsurada 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2010,80(1):37-45
In (Katsurada in Math. Z. 259:97–111, 2008), we gave a certain type of normalization of the standard zeta values for Siegel modular forms, and considered the relationship between such values and congruence of cuspidal Hecke eigenforms. In this paper we give more reasonable normalization for such values and improve our previous result. 相似文献
92.
93.
Yoichi Kamihara Hidenori Hiramatsu Hiroshi Yanagi Hideo Hosono 《Journal of Physics and Chemistry of Solids》2008,69(11):2916-2918
Effects of the replacement of La with Ce on the electronic and magnetic properties of a layered superconductor LaFePO (Tc=∼5 K) were studied. Polycrystalline samples of CeFePO, prepared by a solid-state reaction, showed metallic conduction down to 2 K without exhibiting superconducting transition, although the resistivity decreased largely at temperatures below 30 K. Further, they showed an apparent positive magnetoresistance (MR) below ∼2 K, superposed on a negative MR. Temperature dependence of magnetic susceptibility is decomposed to a temperature-sensitive Curie-Weiss component presumably due to the Ce3+ ions with a magnetic moment of 1.98μB and a less temperature-sensitive component attributable to itinerant electrons. The magnetic interaction between Ce3+ ions and itinerant electrons in CeFePO likely suppresses the superconducting transition observed in LaFePO. 相似文献
94.
Alleviation of thermally induced phase mismatch in CsLiB6O10 crystal by means of temperature-profile compensation 总被引:1,自引:0,他引:1
A new mechanism was found to alleviate the thermally induced phase mismatch of nonlinear optical crystals. By cooling CsLiB>(6)O(10) at an elevated crystal temperature with gas, we improved laser conversion efficiency from green (532 nm) to UV (266 nm) 2.3 times compared with that without cooling. In situ observation of the temperature profile on the output surface revealed that such cooling initiates a negative temperature profile that compensates for the positive profile generated from laser absorption. A 10.6-W UV output with excellent stability was generated. The optimum crystal length was substantially extended. 相似文献
95.
Suetsuna T Dragoe N Harneit W Weidinger A Shimotani H Ito S Takagi H Kitazawa K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(22):5079-5083
We describe the HPLC separation and identification of N@C60 and N2@C60. These species were observed after eleven sequential HPLC separations. Their retention times are in the same range as those of the other noninteractive endohedral species of C60, such as noble gas endohedral C60. The separation factors of these endohedrals were evaluated by using a mixture of hexane/toluene as eluent. We note that this is the first evidence for the N2@C60 molecule existing in the form of endohedral C60 complex. 相似文献
96.
Niko Radulovi? Gordana Stojanovi? Rastko Vuki?evi? Vidoslav Deki? Biljana Deki? Radosav Pali? 《Monatshefte für Chemie / Chemical Monthly》2006,10(3):1477-1486
The one pot reaction preparation, spectral analysis, and molecular modeling experiments on the new 3,4-annelated coumarin
systems with bioactivity associated structural features are described. These provided the insight into the equilibrium of
the respective tautomeric forms making possible the reconciliation of previously published spectral data with the structure
assignments as well as the correction of erroneously established structures. The synthesized compounds were tested in a standard
disk diffusion assay and displayed strong to moderate antimicrobial activity, with a promising new lead prototype compound
(7-amino-9-hydroxy-5-oxa-7a,8,11-triazacyclopenta[b]phenanthren-6-one (5)) possessing greater activity that the antibiotics Ampicillin and Nystatin. Antioxidant capacities of the compounds, determined
spectrophotometrically using a phosphomolybdenum method, were greater, and in the case of compound 5 four times the activity of α-tocopherol acetate. 相似文献
97.
[chemical reaction: see text]. Diorganophosphide anions, which usually function as nontransferable ligands on mixed cuprates, undergo smooth 1,2-migration on ate-type copper carbenoids. Phosphinodisilylmethylcoppers prepared by this protocol are converted into the corresponding phosphines, which can be used as bulky, highly basic and air-stable ligands. 相似文献
98.
Cobalt/N-heterocyclic carbene system or cobalt/diamine combination effectively catalyzes sequential cyclization/cross-coupling reactions of 6-halo-1-hexene derivatives with trialkylsilylmethyl, 1-alkynyl, and aryl Grignard reagents. The sequential cyclization/cross-coupling reactions are applied to the synthesis of 1,3-diols starting from siloxy-tethered 6-halo-1-hexene derivatives. 相似文献
99.
Fixed bed adsorption experiments were performed using four granular activated carbon (GAC) columns designed by packing two
size ranges of pulverized and sieved Filtrasorb 400 (d=0.5-0.59 and 1.0-1.19 mm) to two bed depths (L=10 and 20 cm), respectively. Continuous supplying of river water containing a lower content of natural organic matter (NOM)
allowed investigation of the breakthrough of aqueous natural organic matrices assessed with lumped quality indices of total
dissolved organic carbon (DOC) and ultraviolet absorbance at 260 nm (UV260). The capability of GAC columns in dealing with
sudden rise in the load of influent NOM was also displayed by intermittently adding to the influent river water a peaty field
groundwater that contained a higher content of NOM. Besides, assisted by the size-exclusion HPLC (SEHPLC), changes in the
apparent molecular weight distribution of NOM along the bed depth of GAC columns were evaluated, and an important finding
revealing relatively even adsorption for adsorbable NOM constituents within the entire molecular weight range of 1000-5200 g mol−1 as PSS (polystyrene sulfonates) detected for the river and groundwater NOM was obtained. Furthermore, using a previously
proposed hypothetical multi-component approach incorporating the ideal adsorbed solution theory and a plug flow homogeneous
surface diffusion model, the observed concentration profiles of the river water NOM were predicted. 相似文献
100.
Noguchi H Yoda E Ishizawa N Kondo JN Wada A Kobayashi H Domen K 《The journal of physical chemistry. B》2005,109(36):17217-17223
The reaction dynamics of trans-2-butene adsorbed to acidic hydroxyl groups on the surface of ferrierite zeolite is examined by time-resolved spectroscopy using a tunable infrared picosecond pulse laser system. The transient absorption spectra measured by a two-color pump-probe technique at 188-243 K reveal bleaching and hot bands of the OD stretching mode 2 ps after excitation. This vibrationally excited state relaxes within 20 ps at 188 K, while the bleaching band includes a long-lifetime component that lasts for more than 100 ps at 243 K. Thus, the OD (isotope-exchanged hydroxy groups) stretching band does not entirely recover in this period and is mirrored by an analogous weakening of the CH bending band of the adsorbed trans-2-butene. Simultaneously, three new bands in CH stretching region were observed at 3045, 3095, and 3130 cm(-1). This result suggests the presence of a short-lived intermediate formed by reaction between the acidic hydroxyl groups and adsorbed trans-2-butene. 相似文献