普通高校开展脚斗士体育教学课程的可行性研究

在普通高校大学生中推广脚斗士运动,不仅可以丰富高校体育活动,而且也可促进学校体育向快乐体育方向发展.脚斗士运动规则简单,富有趣味性、竞技性、观赏性和安全性,适合高校体育课程的开展.探讨了脚斗士的起源、特点及在普通高校开展脚斗士的可行性.     

关于序列商π的（P）映射

建立了度量空间的序列商π的（P）映像的内在特征.     

不同喀斯特土壤类型下常见蕨类植物氮磷养分策略差异及其与土壤养分供给关系

蕨类植物是喀斯特生态系统的先锋植物,研究其对瘠薄的喀斯特地区土壤的适应策略,对退化生态系统的恢复与重建具有重要意义。本研究以贵州省植物园内地带性黄壤、非地带性石灰土上均有分布的常见蕨类植物毛蕨[Cyclosorus interruptus (Willd.) H.Ito]、剑叶凤尾蕨(Pteris ensiformis Burm.)和金粉蕨[Onychium siliculosum (Desv.) C.Chr.]为试验材料,研究2种喀斯特土壤类型下3种常见蕨类植物氮磷养分策略的差异,及其与土壤氮磷养分供给的关系。结果表明：①石灰土上蕨类植物根系分泌的有机酸主要为酒石酸、草酸和苹果酸,黄壤上为酒石酸、苹果酸和柠檬酸,且石灰土上根系分泌的有机酸总量远高于黄壤;②与黄壤上生长的蕨类植物相比,石灰土上蕨类植物干物质积累量、氮素与磷素吸收量均较高,分别高出2.7倍、30.8%和43.8%;③2种土壤条件下蕨类植物地上部分的氮(N)、磷(P)平均含量均较地下部分高;石灰土上蕨类植物地上部分N/P为13.17,黄壤上为11.35;④2种土壤条件下蕨类植物的氮素吸收量均与土壤有效磷含量呈显著正相关,说明蕨类植物对土壤氮素的吸收利用受土壤有效磷含量的限制。综上可知,蕨类植物在2种土壤类型上的氮磷养分利用与分配策略存在显著差异,其在石灰土上生长时对土壤养分循环的影响较黄壤上大。     

基于主成分分析和Fisher准则的脑电信号分类

脑-机接口(brain-computer interaction,BCI)利用脑电信号实现人脑与计算机或其它电子设备的通讯和控制,P300拼写范式是脑机接口中的一种常用方法.将遗传算法和支持向量机用于脑电信号的分类.选取三个实验者的实验数据作为处理对象,采用主成分分析和Fisher准则相结合提取特征.在用主成分分析降维后,Fisher准则进一步提取有效特征,提升分类准确率.采用支持向量机对特征数据分类.Fisher准则在特征提取中具有良好的效果.     

Mobility of small molecules in membrane materials based on copolyimide P84

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Beryllium(II) Complexes with Bis(dimethylamino)phosphorylfluoride: A Multinuclear NMR (31P, 19F,and 9Be) Characterization in Solution

Complexes of beryllium chloride and nitrate with (Me₂N)₂P(O)F were characterized in solution by multinuclear NMR spectroscopy and in some cases by IR spectroscopy and conductimetry. ³¹P and ¹⁹F NMR spectra were informative of changes associated with complex formation revealing resonances consistent with different species in solution and suggest an equilibrium between these species in both beryllium derivatives. These compounds show narrow lines in the solution ⁹Be NMR spectra, indicative of a highly symmetric environment for beryllium. The presence of the different species was more pronounced in beryllium chloride complexes. The results are compared to those reported in the literature for hexamethylphosphoramide (HMPA).     

1-(2′,2′,2′-Trifluoroethyl)-4-phosphopyrazoles: Synthese et Etude Spectroscopique ir et RMN 1H, 13C, 19F,et 31P

Seven new 1-fluorinated-4-phosphopyrazoles 2 have been prepared in 60–94% yield by cyclization of N-(2′,2′,2′-trifluoroethyl) phosphonyl β-hydrazones 1 with triethyl orthoformate in the presence of acetic acid. The IR data, the ¹H, ¹³C, ¹⁹F, ³¹P chemical shifts and coupling constants of the compounds 2 are reported.     

The Synthesis and 31P NMR Spectral Studies of Cyclophosphazenes

A modified method for preparing large-scale quantities of pure hexachlorocyclophosphazene (N₃P₃Cl₆) and octachlorocyclotetraphosphazene (N₄P₄Cl₈), phosphorus pentachloride with ammonium chloride, in the presence of zinc chloride, has been developed. The time of the reaction and the quantities of the catalyst are also studied. It is found that the optimum reaction time is 1.5 h and by-products are remarkably reduced by addition of 10% zinc chloride. As indicated by the ³¹ P NMR spectra, the synthesis and separation of cyclophosphazenes can be accomplished in moderate yield of tetramer (39%) and good yield of trimer (83%).