新型二元致孔剂Pluronic F127/十二胺用于辛基杂化整体柱的合成与色谱性能评价

采用新型二元致孔剂Pluronic F127/十二胺,通过两步溶胶-凝胶法合成了辛基杂化整体柱,并用于稠环物质、苯系物以及水体中8种生物毒素的毛细管液相色谱分离分析.在整体柱的形貌方面,F127的加入使材料由聚集球状结构转变成双连续孔结构,并实现了对材料通孔、骨架以及骨架上介孔的尺寸调节,得到了更适于小分子分离的结构.此外,通过减少十二胺用量使凝胶化时间延长,显著降低了灌柱的难度以及灌柱时可能引起的材料不均匀和重复性差的问题.优化后的辛基杂化整体柱保持了良好的机械稳定性和高渗透性,塔板数为49000/m,与传统的制备方法相比柱效明显提高.在对稠环物质、苯系物等典型小分子的测试中均得到了良好的分离效果.新型二元致孔剂的辛基杂化整体柱制备更容易,形貌控制简单,稳定性好,实用性显著增强.     

Two Polynuclear Fe Complexes with Boat-like Core:Syntheses,Structures and Magnetic Properties

Two novel polynuclear complexes{NaFe4（μ₄-O）(L)4（μ₂-Cl）[Fe（CN）₅NO]（H₂O）(DMF)2}（1） and{NaFe4（μ₄-O）(L)4（μ₂-OEt）[Fe（CN）₅NO]（H₂O）(DMF)₂}（2） have been prepared using the tetradentate N-（2-hydroxyethyl）-3-methoxysalicylaldimine Schiff-base ligand （H₂L） with the help of[Fe（CN）₅NO]^2-linkers,where the ligand was in situ synthesized through the condensation of o-vanillin and e...     

贵州凤冈县宜茶区土壤重金属含量状况及污染评价

对贵州凤冈县14个乡镇的宜茶土壤中汞、镉、铅、砷、铬、铜6种重金属含量进行统计分析,根据NY/T 5020-2001《无公害食品茶叶产地环境条件》、NY 5199-2002《有机茶产地环境条件》、NY/T 5295-2004《无公害食品产地环境评价准则》进行评价,为凤冈县茶园建设规划提供理论依据。     

半导体InAs量子点单光子发射器件

文章概述了量子点单光子源的研究现状,综述了微腔量子点耦合单光子发射器件制备中关键的低密度InAs量子点外延技术,单量子点单光子发射二阶关联函数HBT检测方法,分布布拉格反馈微腔结构的制备以及实现液氮温度下电驱动微腔量子点单光子发射器件等研究结果.     

Growth of aligned single-walled carbon nanotubes under ac electric fields through floating catalyst chemical vapour deposition

Through floating catalyst chemical vapour deposition(CVD) method,well-aligned isolated single-walled carbon nanotubes (SWCNTs) and their bundles were deposited on the metal electrodes patterned on the SiO₂/Si surface under ac electric fields at relatively low temperature(280℃). It was indicated that SWCNTs were effectively aligned under ac electric fields after they had just grown in the furnace.The time for a SWCNT to be aligned in the electric field and the effect of gas flow were estimated. Polarized Raman scattering was performed to characterize the aligned structure of SWCNTs. This method would be very useful for the controlled fabrication and preparation of SWCNTs in practical applications.     

对“一维链状冠醚配合物[K(B18-C-6)]_2[M(SCN)_4](M=Pd,Pt)的合成与结构”一文的更正

我们合成、表征了苯并 1 8 冠 6(B1 8 C 6)与K2 [Pd (SCN) 4 ],K2 [Pt(SCN) 4 ]生成的一维链状配合物 [K(B1 8 C 6) ]2 [Pd(SCN) 4 ]( 1 ) ,[K(B1 8 C 6) ]2 [Pt(SCN) 4 ]( 2 )和[K(B1 8 C 6) ]2 [Pt(SCN) 4 ]·C2 H4Cl2 ( 3 ) .其中 3为三斜晶系 ,空间群P1 [化学学报 2 0 0 2 ,60 ( 8) ,1 465 ].厦门大学胡盛志教授认为该化合物的空间群应为P 1 .经将原始数据重新还原、修正 ,3的空间群的确为P 1 ,现予以更正 .配合物 3部分结构数据由表 1给出 ,其非氢原子坐标和热参数列于表 2 ,部分键长和键角列于表 3 .晶体结构和堆积图…     

基于InAs单量子点的单光子干涉

利用分子束外延生长 InAs 单量子点样品,测量了温度为 5 K 时单量子点的荧光(PL)光谱.采用时间关联光子强度测量(HBT)验证了 PL 光谱具有单光子发射特性.单光子通过马赫曾德尔 (MZ) 干涉仪,验证了单光子自身具有干涉特性.测量了当 MZ 干涉仪两臂偏振方向的夹角改变时对应的单光子干涉及条纹可见度的变化. 关键词： 量子点单光子源 反群聚效应 马赫曾德尔干涉     

Cu/SBA-1的合成及其对苯羟化反应的催化性能

以正硅酸乙酯(TEOS)为硅源,十六烷基三乙基溴化铵(CTEABr)为模板剂,在强酸性条件下采用溶胶-凝胶法合成了Cu掺杂SBA-1分子筛.用XRD、SEM、N2吸附/脱附、红外光谱对所制备的样品进行表征.XRD测定结果显示所合成的Cu/SBA-1具有明显的立方介孔结构,Cu/SBA-1比表面积达931 m2·g-1,...     

Pressure- and temperature-dependent luminescence from Tm3+ ions doped in GdYTaO4

Luminescent properties of Tm³⁺-doped GdYTaO₄ are studied for exploring their potential applications in temperature and pressure sensing.Two main emission peaks from ³H₄→³H₆ transition of Tm³⁺are investigated.Intensity ratio between the two peaks evolves exponentially with temperature and has a highest sensitivity of 0.014 K^?1 at 32 K.The energy difference between the two peaks increases linearly with pressure increasing at a rate of 0.38 meV/GPa.Intensity ratio between the two peaks and their emission lifetimes are also analyzed for discussing the pressure-induced variation of the sample structure.Moreover,Raman spectra recorded under high pressures indicate an isostructural phase transition of GdYTaO₄ occurring at 4.46 GPa.     

Gate tunable Rashba spin-orbit coupling at CaZrO3/SrTiO3 heterointerface

High mobility quasi two-dimensional electron gas (2DEG) found at the CaZrO₃/SrTiO₃ nonpolar heterointerface is attractive and provides a platform for the development of functional devices and nanoelectronics. Here we report that the carrier density and mobility at low temperature can be tuned by gate voltage at the CaZrO₃/SrTiO₃ interface. Furthermore, the magnitude of Rashba spin-orbit interaction can be modulated and increases with the gate voltage. Remarkably, the diffusion constant and the spin-orbit relaxation time can be strongly tuned by gate voltage. The diffusion constant increases by a factor of ～ 19.98 and the relaxation time is reduced by a factor of over three orders of magnitude while the gate voltage is swept from -50 V to 100 V. These findings not only lay a foundation for further understanding the underlying mechanism of Rashba spin-orbit coupling, but also have great significance in developing various oxide functional devices.