基于EMD和PCA的暂态电能质量消噪

针对电能质量扰动的消噪问题,提出一种基于经验模态分解(EMD)和主成分分析(PCA)的消噪方法.方法先用EMD将信号分解为一组内蕴模态函数(IMF),对第一层IMF进行细节信息提取,然后对第二层及其后面的IMF进行PCA变换,根据噪声能量选择合适的主成分分量重构,去除各层IMF中的噪声.分别用电压聚降、电压中断、暂态脉冲、谐波及其组合进行数字仿真,和SureShrink小波阈值法、BayesShrink小波阈值法去噪结果比较,所用的方法去噪效果优于SureShrink小波阈值法、BayesShrink小波阈值法去噪结果,尤其对于电压暂降、电压中断、电压聚升这几个最重要的暂态电能质量问题消噪效果更为明显,结果证实了其有效性.     

线性代数与空间解析几何新形态教材建设的实践与思考

从线性代数与空间解析几何课程发展历史引入,对比分析传统教材内容与体系的差异,在此基础上探讨信息技术与教育教学深度融合背景下新形态教材出版的必要性,进而阐述线性代数与空间解析几何新形态教材出版创新的探索与实践,最后浅谈新形态教材建设的几点思考.     

Molecular dynamics simulation of latent track formation in α-quartz

The latent ion track in α-quartz is studied by molecular dynamics simulations. The latent track is created by depositing electron energies into a cylindrical region with a radius of 3nm. In this study, the electron stopping power varies from 3.0keV/nm to 12.0keV/nm, and a continuous latent track is observed for all the simulated values of electron stopping power except 3.0keV/nm. The simulation results indicate that the threshold electron stopping power for a continous latent track lies between 3.0keV/nm and 3.7 keV/nm. In addition, the coordination defects produced in the latent track are analyzed for all the simulation conditions, and the results show that the latent track in α-quartz consists of an O-rich amorphous phase and Si-rich point defects. At the end of this paper, the influence of the energy deposition model on the latent track in α-quartz is investigated. The results indicate that different energy deposition models reveal similar latent track properties. However, the values of the threshold electron stopping power and the ion track radius are dependent on the choice of energy deposition model.     

具有聚集荧光增强性质的双(4-二乙氨基水杨醛)缩偶氮二甲酰肼二丁基锡的合成和晶体结构

在甲醇溶液中,卡巴肼、(4-二乙氨基)水杨醛和二乙酸二丁基锡"一锅法"反应,合成了一个新颖的基于双(4-二乙氨基水杨醛)缩偶氮二甲酰肼(L)的七配位有机锡配合物[Sn(L)(n-butyl)_2]n(T)。经元素分析、IR、(1H,119Sn,13C)NMR和X射线衍射晶体结构表征,T的晶体属单斜晶系C2/c空间群,中心锡周围由双(4-二乙氨基水杨醛)缩偶氮二甲酰肼的O,N配位原子占据赤道位置和2个丁基占据顶端位置形成畸变五角双锥构型。通过烯醇式氧原子的桥联配位作用,T向一维带状无限扩展产生"竹筏状"超分子结构。配合物T在二甲基甲酰胺、四氢呋喃、乙醇、甲醇和甲苯有机溶剂及其有机溶剂-水混合物中具有强荧光发射峰,当含水量的体积分数在0～10%(V/V)时具有良好的聚集荧光增强效应,含水量大于10%(V/V)时发生荧光淬灭。     

Syntheses,Structures and Herbicidal Activity of Bis(5-R-2-hydroxybenzylidene) Thiocarbohydrazide Monobutyltin Complexes [R: H(T1), Me(T2)]

The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes, [(5-R-2-hydroxy)ArCH=NNH]_2 CS(n-BuSnCl)_2, R = H(T1); R = Me(T2), based on the1,5-disubstituted thiocarbohydrazide were obtained by microwave-assisted solvothermal reaction of n-butyltintrichloride precursor with the ligands in methanol environments, which have been structurally characterized by elemental analysis, IR and(~1 H, ~(13) C) NMR spectra. The crystals belong to monoclinic system, space groups C2/c(T1) and Pc(T2), respectively. The Sn atom is six-coordinated with distorted octahedral geometry by O, N and S atoms from ligand, C atom of butyl and two Cl atoms. In the crystal, complex T1 forms three-dimensional supramolecular assembly mediated by noncovalent interactions such as C–H···Cl and π-stacking interactions.Similarly, T2 forms an interesting two-dimensional supramolecular structure by noncovalent interactions(e.g. C–H×××Cl and N–H×××Cl) of one-dimensional band-like chain. These ligands and its butyltin complexes have growth effect on the target plants, such as Portulaca oleracea L.,Amaranthus spinosus L., Cassia tora L., Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee and Amaranthus tricolor L. The ligand L1 has a good inhibitory effect on the growth of Cassia tora L., and complex T2 has selective inhibition on the growth of Portulaca oleracea L. and Amaranthus tricolor L., which can be used as a candidate compound for Cassia tora L., Portulaca oleracea L.and Amaranthus tricolor L. herbicide.     

超声促进2-磺酰基氮杂环化合物的合成研究

探索了一种超声促进合成2-磺酰基氮杂环化合物的反应.以氮杂环氮氧化物和亚磺酸为原料,以三吡咯烷基溴化鏻六氟磷酸盐(Py Bro P)为催化剂,室温下超声反应1.0 h,能够以良好的收率得到2-磺酰基氮杂环化合物.该反应具有底物适用性好,反应时间短,反应产率高等优点,为高效合成2-磺酰基氮杂环化合物及其衍生物提供了一种新的途径.     

环状二聚三(邻甲基苄基)氢氧化锡的合成、结构及量子化学研究

三(邻甲基苄基)锡氯化锡在氢氧化钠溶液中水解, 合成了环状二聚三(邻甲基苄基)氢氧化锡, 经X射线衍射方法测定了化合物的晶体结构, 属三斜晶系, 空间群为P-1, 晶体学参数: a＝1.00530(18) nm, b＝1.03580(18) nm, c＝1.08182(18) nm, α＝90.151(3)°, β＝108.317(3)°, γ＝94.871(3)°, V＝1.0650(3) nm3, Z＝1, Dc＝1.380 g/cm3, m(Mo Kα)＝0.1205 cm－1, F(000)＝451, R1＝0.0330, Rw＝0.0822. 化合物为由Sn2O2构成的平面四元环结构, 锡原子为五配位的三角双锥构型. 对其结构进行量子化学从头计算, 探讨了化合物的稳定性、分子轨道能量以及一些前沿分子轨道的组成特征.     

基于化学模式识别和熵权TOPSIS法分析鱼腥草不同部位的差异

基于高效液相色谱（HPLC）指纹图谱比较鱼腥草不同部位（茎、叶）化学成分的差异性,并综合评价鱼腥草不同部位的质量。建立鱼腥草不同部位的HPLC指纹图谱,通过相似度评价、化学模式识别及熵权TOPSIS法对其化学成分进行差异性研究,并对其质量标志物（槲皮苷）进行含量测定。建立的HPLC指纹图谱中鱼腥草药材及其茎叶均确定了8个共有峰,指认了其中6个成分;聚类分析（CA）和主成分分析（PCA）结果表明鱼腥草叶和茎的质量差异大,叶和药材的质量较接近;偏最小二乘法-判别分析（OPLS-DA）发现4种成分是造成不同批次样品差异性的主要标志物;熵权TOPSIS法分析显示同批次鱼腥草药材与其茎叶既有相关性也有差异性,且四川产地的鱼腥草药材质量较佳;含量测定结果显示,同批次鱼腥草中的槲皮苷含量由高到低均依次为叶、药材、茎。鱼腥草不同部位HPLC指纹图谱存在显著差异。该方法可反映鱼腥草不同部位质量差异性,为鱼腥草药材的质量控制及资源开发利用提供参考。     

[Zn(phen)3]·2Bsesa·4H2O配合物的合成及其晶体结构

在水醇溶液中合成了配合物[Zn(phen)3]·2Bsesa·4H2O(1,phen=邻菲咯啉,BsesaH=苯磺酰牛磺酸),其结构经IR,元素分析和X-射线衍射表征.1属三斜晶系,P-1空间群,晶胞参数:a=1.111 5(3)nm,b=1.415 5(4)nm,c=1.748 6(5)nm,α=80.764(5)°,β=87.237(5)°,γ=88.081(5)°,V=2.711 3(14)nm3,Z=2,Dc=1.478 g·cm-3,μ=0.681 mm-1,F(000)=1 252.1为变形的八面体构型,Zn(Ⅱ)与3个邻菲咯啉配位,未与苯磺酰牛磺酸中的氧原子配位.     

表面活性剂增敏3'-甲氧基-4'-羟基苯基荧光酮光度法测锗的研究

研究了阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下3'-甲氧基-4'羟基苯基荧光酮(MHPF)与Ge(Ⅳ)的显色反应.在HCl介质中,CTMAB的存在对MHPF与Ge(Ⅳ)的显色反应有显著的增敏作用,Ge(Ⅳ)与MHPF形成稳定的1:2红色配合物.配合物最大吸收波长位于505 nm,表观摩尔吸光系数为1.72×105L·mol-1·cm-1.锗量在0～0.48 mg/L范围符合比耳定律.方法已用于铅锌矿渣中微量锗的测定.