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1.
Science China Mathematics - This paper studies exact synchronization and asymptotic synchronization problems for a controlled linear system of ordinary differential equations. In this paper, we... 相似文献
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We numerically solve the time-dependent Ginzburg–Landau equations for two-gap superconductors using the finite-element technique. The real-time simulation shows that at low magnetic field, the vortices in small-size samples tend to form clusters or other disorder structures. When the sample size is large, stripes appear in the pattern. These results are in good agreement with the previous experimental observations of the intriguing anomalous vortex pattern, providing a reliable theoretical basis for the future applications of multi-gap superconductors. 相似文献
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本文主要讨论带有分数阶耗散项的quasi-geostrophic(QG)方程的周期解的大时间性态,并且对初值θ_0没有小性的要求.对于次临界(1/2α1)和临界(α=1/2)两种情况,证明了方程的周期解均具有指数级的衰减性. 相似文献
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Lijuan Shen Li Li Sheng Lu Xiaohan Zhang Jie Liu Junlin An Guojun Zhang Bo Wu Fei Wang 《中国颗粒学报》2015,(3):10-15
We conducted measurements of black carbon(BC) aerosol in Jiaxing,China during autumn from September 26 to November 30,2013.We investigated temporal and diurnal variations of BC,and its correlations with meteorological parameters and other major pollutants.Results showed that hourly mass concentrations of BC ranged from 0.2 to 22.0 μg/m3,with an average of 5.1 μg/m3.The diurnai variation of BC exhibited a bimodal distribution,with peaks at 07:00 and 18:00.The morning peak was larger than the evening peak.The mass percentages of BC in PM2.5 and PM10 were 7.1%and 4.8%,respectively.The absorption coefficient of BC was calculated to be 44.4 Mm-1,which accounted for 11.1%of the total aerosol extinction.BC was mainly emitted from local sources in southwestern Jiaxing where BC concentrations were generally greater than 11 μg/m3 during the measurement period.Correlation analysis indicated that the main sources of BC were motor vehicle exhaust,and domestic and industrial combustion. 相似文献
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在水热环境下,将Na10[α-SiW9O34]爛18H2O和CuCl2爛2H2O在2,2′-联咪唑和4,4′-联吡啶存在下反应合成一种饱和Keggin硅钨酸盐杂化物[Cu(biim)2]4[α-SiW12O40]2爛4H2O(1),并通过红外光谱,X射线光电子能谱和X射线单晶衍射进行了结构表征.化合物1分子包含2个中性的Keggin[Cu(biim)2]2[α-SiW12O40]单元和4个结晶水分子.值得注意的是在[α-SiW12O40]4-单元中,与硅原子相连的每个氧原子无序排列在两个位置,这导致了硅原子呈现立方体的几何构型.中性Keggin型[Cu(biim)2]2[α-SiW12O40]单元具有中心对称性,两个[Cu(biim)2]2+配离子对称连接在[α-SiW12O40]4-的两端.邻近的[Cu(biim)2]2[α-SiW12O40]单元之间通过氢键作用形成三维的超分子结构. 相似文献
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"教-学-评一体化"的课堂是指围绕教学目标,教师的教学、学生的学习以及教师对学生的评价组成一个有机的、整体的有效课堂.教学"有效"的唯一证据在于目标的达成,在于学生学习结果的质量,在于何以证明学生学会了什么.因此,教学中要关注对学生的评价.本文以"示波器的原理——带电粒子在电场中的偏转"为例,论述在"教-学-评一体化"的课堂中如何用评价促进学生思维发展. 相似文献
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Bioanalysis assays that reliably quantify biotherapeutics and biomarkers in biological samples play pivotal roles in drug discovery and development. Liquid chromatography coupled with mass spectrometry (LC–MS), owing to its superior specificity, faster method development and multiplex capability, has evolved as one of the most important platforms for bioanalysis of biotherapeutics, particularly new scaffolds such as half-life extension platforms for proteins and peptides, as well as antibody drug conjugates. Intact LC–MS analysis is orthogonal to bottom-up surrogate peptide approach by providing whole molecule quantitation and high-level sequence and structure information. Here we review the latest development in LC–MS bioanalysis of intact proteins and peptides by summarizing recent publications and discussing the important topics such as the comparison between top-down intact analysis and bottom-up surrogate peptide approach, as well as simultaneous quantitation and catabolite identification. Key bioanalytical issues around intact protein bioanalysis such as sensitivity, data processing strategies, specificity, sample preparation and LC condition are elaborated. For peptides, topics including quantitation of intact peptide vs. digested surrogate peptide, metabolites, sensitivity, LC condition, assay performance, internal standard and sample preparation are discussed. 相似文献