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排序方式: 共有395条查询结果,搜索用时 15 毫秒
1.
You Hui Er Cai Ru 《科技信息》2007,(33)
从设计定位、空间布局、技术细节三方面入手,详细介绍了华南理工大学建筑设计院创作室环境设计的理念和手法。论述了作为建筑设计事务所周边环境的设计,如何做到如寻常景观一般与原有环境相融合的协调,并从中总结经验和教训。 相似文献
2.
通过对孙悟空形象的分析,探讨了《西游助中所蕴含的禅宗重领悟贵言外的宗教哲理。尤其是它注重内心的感悟,擅长畜于哲理的启示,对中国小说创作的丰富和完备起到了重要的作用。 相似文献
3.
Pentacoordinate complex cations of the general formula [(C6F5)2SbL3]3+ stabilized as solid salts in combination with tetraphenylborate (BPh4), tetrafluorobroate (BF4) anions, where L=DMSO, Ph3AsO, PyO, DMF, α-, β- and γ-picoline have been isolated. The newly formed complexes were characterized by elemental analysis, molar conductance measurements, solid-state IR and and NMR. From these results, a five-fold coordination around antimony was required. 相似文献
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Anna B. DenisovaVyacheslav Ya. Sosnovskikh Wim Dehaen Suzanne ToppetLuc Van Meervelt Vasiliy A. Bakulev 《Journal of fluorine chemistry》2002,115(2):183-192
Reaction of 2-hydrazinothiazoles 1 with 1-thienyl- and 1-furyl-1,3-butanediones 2a,b in methanol in the presence of hydrochloric acid mainly leads to a mixture of pyrazoles 3 and pyrazolines 4 or pyrazoles 3 and 5 in strong acidic conditions. Isomeric hydrazones 6 and pyrazolines 4 were formed and isolated in these reactions in the absence of hydrochloric acid. It has been shown that the regioselectivity in the reaction of diketones 2 with hydrazine 1 is governed by both the concentration of acid and the nature of substituents in the 1,3-diketones 2. Cyclization of hydrazones 6 is shown to occur under milder conditions than dehydration for pyrazolines 4. The new heterocyclic compounds were prepared and fully characterized by NMR spectra and by X-ray analysis for 3c. 相似文献
6.
The molecular structure and absorption spectra of monothio- and dithio-naphthalimides were compared to their naphthalimide analogues using AM1, PM3 and ZINDO/S semiempirical quantum chemical methods. The substitution of the 4R-naphthalimide oxygen atoms by sulphur atoms resulted in a red-shift of the absorption spectra by Δλmax60-65 and 100-140 nm, respectively. The thionated naphthalimide derivatives do not show observable fluorescence due to intersystem crossing to the triplet -states localised at the CS groups. The -absorption bands of monothioimides are located at 525-580 nm (ε=60-80) and those for dithioimides at 535-560 nm (ε=140-390) and 628-686 nm (ε=34-68). None of these transitions are solvent sensitive. The -transitions of N-phenylthioimides have also a small contribution from -states due to a partial conjugation between CS group and π-electronic system of the N-phenyl ring. As a result, the bands of aromatic substituted N-phenylthioimides are red-shifted as compared to those of the aliphatic N-methyl-thioimides. 相似文献
7.
韩冰 《无锡职业技术学院学报》2005,4(2):4-6
课程观是课程开发、课程实施和课程评价的基本出发点,当前高职课程观从总体上可分为学科课程观和活动课程观两大类,二者均忽视作为课程存在基本条件的学生。要以学生的发展为视角,关注学生个体差异、关注学生认知、情感、态度的形成,树立开放的课程观。 相似文献
8.
遗传算法中交叉算子的配对策略研究 总被引:5,自引:0,他引:5
提出了一种称为“国王配对”的配对策略来选择进行交叉运算的父母体,在此基础上再执行改进的交叉运算.经过测试,证明国王配对策略比随机配对策略要优越,可以加速遗传算法的进化过程. 相似文献
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10.
Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm 总被引:1,自引:0,他引:1
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Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed, and a fitness function is provided. Simulations are conducted using the adaptive niche immune genetic algorithm, the simulated annealing algorithm, the quantum genetic algorithm and the simple genetic algorithm, respectively. The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation, and has quick convergence speed and strong global searching capability, which effectively reduces the system power consumption and bit error rate. 相似文献