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正规子群中某些p-A正则元的G-共轭类长 被引量:2
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作者 赵先鹤 左红亮 陈贵云 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第4期104-108,共5页
设N0是有限群G的p-可解的正规子群,m>n≠1是2个互素的正整数.主要证明了当N0中p-正则的素元和双素元的G-共轭类长是1,n或m时,N0/N0∩Z(G)的p-补要么是素数幂阶群,要么是可解的Frobenius群.
关键词 有限群 G-共轭类长 p-正则元 素元 双素元
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Image edge detection based on nonsubsampled contourlet transform and mathematical morphology 被引量:1
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作者 何坤贤 王庆 +1 位作者 肖彦昌 王晓兵 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期445-450,共6页
A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled conto... A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled contourlet transform into multi-scale and multi-directional subbands. Then the edges in the high-frequency and low-frequency sub-bands are respectively extracted by the dualthreshold modulus maxima method and the mathematical morphology operator. Finally, the edges from the high- frequency and low-frequency sub-bands are integrated to the edges of the source image, which are refined, and isolated points are excluded to achieve the edges of the source image. The simulation results show that the proposed algorithm can effectively suppress noise, eliminate pseudo-edges and overcome the adverse effects caused by uneven illumination to a certain extent. Compared with the traditional methods such as LoG, Sobel, and Carmy operators and the modulus maxima algorithm, the proposed method can maintain sufficient positioning accuracy and edge details, and it can also make an improvement in the completeness, smoothness and clearness of the outline. 展开更多
关键词 image edge detection nonsubsampled contourlet transform NSCT modulus maxima DUAL-THRESHOLD mathematical morphology structural elements
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An Analysis of Anton Von Webem's Concerto for Nine Instruments
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作者 Esra Karaol 《Journal of Literature and Art Studies》 2014年第9期729-739,共11页
Anton Webem's (1883-1945) largest project of the early the 1930s, the Concerto for Nine (solo) Instrument's Op. 24, is for flute, oboe, clarinet, horn, trumpet, trombone, violin, viola, and piano. This serial w... Anton Webem's (1883-1945) largest project of the early the 1930s, the Concerto for Nine (solo) Instrument's Op. 24, is for flute, oboe, clarinet, horn, trumpet, trombone, violin, viola, and piano. This serial work's analysis became almost as famous as the concerto itself. Highly economical, short, concentrated and free relationship between the intervals take over from tonality as the main organizational principle "pontillistic" style. The clear and transparent frame "Klangfarbenmelodie", is a row, that was distributed among different instruments. So that, several notes can be heard in the same timbre. Like most of Webern works, there are quiet special effects like a whisper, string harmonics, pizzicato, muting, and athematic intevalic cells as the basic structural element. Concerto for Nine Instruments has succeeding series of twelve-tone works. Webern worked for a long time on the Concerto's raw, trying to arrive at an equivalent to the Latin word-square palindrome which reads the same left to right from the top, right to left from the bottom, downwards from the top left, or upwards from the bottom right.SATOR AREPO TENET OPERA ROTAS 展开更多
关键词 Webem twelve-tone serialism
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Effect of Phytoestrogen Activity on hFOB 1.19 Osteoblast Cells of Vanilla Siamensis
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作者 Phenphichar Wanachantararak Juraruk Thongpaeng +2 位作者 Fahsai Kantawong Chuenchit Boonchird Griangsak Chairote 《Journal of Chemistry and Chemical Engineering》 2012年第9期843-852,共10页
The unsaponifiable compounds derived from the fresh green beans of Vanilla siamens& Rol. ex. Dow were assayed for the first time to detect their estrogenic activity. We used a simple screening method using the yeast ... The unsaponifiable compounds derived from the fresh green beans of Vanilla siamens& Rol. ex. Dow were assayed for the first time to detect their estrogenic activity. We used a simple screening method using the yeast two hybrid system based on the binding of a ligand to estrogen receptors. Yeast cells carrying the hER (human estrogen receptor) gene, ERE (estrogen response elements) and lacZ (β-galactosidase gene) are very suitable for screening and sensitive analysis of estrogenic compound. Our results showed that V. siamensis plant extracts bind with relatively affinity to YES- hERa was 2.27-fold the relative potency ofestradiol (E2) in YES-hERa. The effects of phytoestrogen activity on the osteoblast cells were examined on the proliferation of hFOB 1.19 cells and the bone mineralization process. V. siamens& was a positive screening result and induced mineralization ofosteoblasts. This study indicated that V. siamensis plant extract exhibited the characteristic effects of a nature bone promoter compound as phytoestrogen. 展开更多
关键词 Vanilla siamensis PHYTOESTROGEN osteoblast cells.
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Bimetallic amine-bridged bis(phenolate) lanthanide aryloxides and alkoxides: synthesis, characterization, and application in the ring-opening polymerization of rac-lactide and rac-β-butyrolactone 被引量:3
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作者 NIE Kun FENG Tao +5 位作者 SONG FengKui ZHANG Yong SUN HongMei YUAN Dan YAO YingMing SHEN Qi 《Science China Chemistry》 SCIE EI CAS 2014年第8期1106-1116,共11页
A series of neutral bimetallic lanthanide aryloxides p-C6H4[OLnL(THF)n]2 [Ln = Y(1), Yb(2), Sm(3)(n = 1) and La(4)(n = 2), L = Me2NCH2CH2N{CH2-(2-O–C6H2–tBu2-3,5)}2] and alkoxides p-C6H4CH2[OLnL(THF)]2 [Ln = Y(5), Y... A series of neutral bimetallic lanthanide aryloxides p-C6H4[OLnL(THF)n]2 [Ln = Y(1), Yb(2), Sm(3)(n = 1) and La(4)(n = 2), L = Me2NCH2CH2N{CH2-(2-O–C6H2–tBu2-3,5)}2] and alkoxides p-C6H4CH2[OLnL(THF)]2 [Ln = Y(5), Yb(6)] supported by an amine-bridged bis(phenolate) ligand have been synthesized through one-pot reactions of Ln(C5H5)3(THF), LH2 with p-benzenediol and 1,4-benzenedimethanol, respectively. All complexes have been fully characterized by elemental analyses, single-crystal X-ray diffraction analysis, and IR and multi-nuclear NMR spectroscopy(in the cases of 1, 4 and 5). Study of their catalytic behavior revealed that, in general, all complexes are efficient initiators for the polymerization of rac-lactide(LA) and rac-β-butyrolactone(BBL), except for 3 and 4 in the case of BBL. The influence imposed by lanthanides of different ionic radii and initiating groups of different structures on the activity, controllability, and stereoselectivity of polymerization were systematically studied and compared. Highly heterotactic PLA(Pr up to 0.99) and syndiotactic PHB(Pr ≈ 0.81) with high molecular weight and narrow polydispersity formed and were automatically capped with hydroxyl functionality at both ends. 展开更多
关键词 amine-bridged bis(phenolate) ligand bimetallic lanthanide aryloxides and alkoxides ring-opening polymerization stereoselectivity
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