氨基化硅藻基As(Ⅴ)印迹复合材料的制备与性能

采用硅藻作为材料载体、选取氨基丙基三甲氧基硅烷(APS)作为功能单体、As(Ⅴ)为模板离子、环氧氯丙烷(ECH)为交联剂通过表面印迹组合,制备了砷离子印迹复合材料,并将其应用于二元体系中对砷离子的选择吸附。采用扫描电镜、X射线光电子能谱、傅立叶变换红外光谱及N_2吸附-脱附实验对材料进行表征,探究了硅藻基表面印迹法的搭接方式:氨基丙基三甲氧基硅烷首先通过缩合反应脱去甲氧基,与硅藻表面的活性羟基形成了(Si-O)_3≡Si-R结构,在硅藻表面形成有效接枝,通过环氧氯丙烷与APS中的氨基交联形成印迹结合位点,从而在硅藻表面形成了具有As(Ⅴ)选择性的复合印迹孔穴。采用选择性系数法,得出离子印迹复合材料对砷离子(As(Ⅴ))的去除率为98%,相对选择性系数(k′)均大于1.5。     

化学职前教师PCK的结构与水平研究

本研究基于定量的研究方式测查189名化学职前教师PCK的结构与水平,结果表明（1）化学职前教师的PCK结构主要包括KoC、KoL、KoS、KoA等4个组分,且该结构具有良好的信度与效度;（2）化学职前教师PCK的4个组分之间存在显著相关,且显性的PCK教学方式比隐性的更有利于职前教师对PCK组分间的整合;（3）化学职前教师的PCK水平除KoS组分水平较为理想,其他知识组分水平均处于中等或中下水平;（4）在不同的PCK教学方式（显性或隐性）下,化学职前教师的PCK水平存在显著性差异。     

甲基膦酸(濒)哪酯分子印迹聚合物的合成与识别特性研究

利用~(31)P{~1H}NMR谱和~1H NMR谱、FT-IR谱等技术手段,研究了化学毒剂梭曼的降解产物(甲基膦酸■哪酯)与甲基丙烯酸、丙烯酰胺功能单体的分子间作用力。通过预组装体系设计,合成了多孔性材料甲基膦酸■哪酯分子印迹聚合物。通过Scatchard模型分析,得到该聚合物对甲基膦酸■哪酯的最大表观结合量Q_(max)为661μg/g(AM为单体),在低吸附量(Q500μg/g)范围内,吸附量对模板浓度的比值与吸附量呈线性相关。通过静态吸附分配实验发现,该聚合物对同系的5种烷基膦酸单烷基酯存在选择性,对结构不同的其他化合物的识别因子显著降低。将该分子印迹聚合物制成固相萃取柱,用于含大量背景干扰的样品中痕量甲基膦酸■哪酯的萃取分离,取得显著效果。该研究为复杂基质中该类化合物的痕量分析鉴定提供了技术手段。     

Carboxyl-functionalized Nanocellulose Reinforced Nanocomposite Proton Exchange Membrane

Nanocellulose(NCC) was prepared through the acid hydrolysis of microcellulose(MCC) and was reacted with maleic anliydride to obtain carboxyl-functionized nanocellulose(MA-NCCs). The presence of .OH and .SO3H on the surface of rod-like MA-NCC was confirmed by Fourier transfonn infrared spectrometry(FTIR). Sulfonated poly(aryl ether ether ketone ketone)(Ph-SPEEKK) was synthesized with bis(4-fluorophenyl-methanone) and 2-phenylhydroquinone as monomer. MA-NCC/Ph-SPEEKK nanocomposite membranes with different MA-NCCs content were prepared, and their properties were characterized. Compared with Ph-SPEEKK, MA-NCC/Ph-SPEEKK nanocomposite membrane showed better mechanical and thermal properties and higher proton conductivity. The proton conductivity of the composite membrane with 4%(mass fraction) MA-NCCs under 80℃ was 0.095 S/cm. And its tensile strength reached 30.3 MPa, which was 21.2% higher than that of Ph-SPEEKK pure polymer membrane.     

Analytic Study of a Bose-Einstein Condensate in Waveguide with an Obstacle Potential

We investigate the exact solutions of one-dimensional （1D） time-independent Gross-Pitaevskii equation （GPE）, which governs a Bose-Einstein condensate （BEC） in the magnetic waveguide with a square-Sech potential. Both the bound state and transmission state are found and the corresponding spatial configurations and transport properties of BEC are analyzed. It is shown that the well-known absolute transmission of the linear system can occur in the considered nonlinear system.     

Collisions of Two Soatial Solitons in Inhomogeneous Nonlinear Media

Collisions of spatial solitons occurring in the nonlinear Schroeinger equation with harmonic potential are studied, using conservation laws and the split-step Fourier method. We find an analytical solution for the separation distance between the spatial solitons in an inhomogeneous nonlinear medium when the light beam is self-trapped in the transverse dimension. In the self-focusing nonlinear media the spatial solitons can be transmitted stably, and the interaction between spatial solitons is enhanced due to the linear focusing effect （and also diminished for the linear defocusing effect）. In the self-defocusing nonlinear media, in the absence of self-trapping or in the presence of linear self-defocusing, no transmission of stable spatial solitons is possible. However, in such media the linear focusing effect can be exactly compensated, and the spatial solitons can propagate through.     

Investigation on Rijke pipe＇s acoustic characteristics by numerical simulation： modeling the pulsing flow field coupled the inner of pipe with its outer space

Based on the results of fluid dynamics, heat transfer and acoustics, a Computational Fluid Dynamics （CFD） method was utilized to study the acoustic characteristics and self-excited pulsation mechanism inside a Rijke pipe. To avoid settling the irrational boundary conditions of the finite-amplitude standing wave in the Rijke thermo-acoustic system, the simulation modeling in the flow field, which coupled the inner of pipe with its outer space, was carried out to replace the traditional way in form of internal flow field numerical investigations. A hypothesis for heat source in energy equation including the relationship on unsteady heat of air around heat source, oscillation pressure and oscillation velocity was presented. To reflect the essence of Rijke pipe, simulation on self-excited oscillation was conducted by means of its own pulsation of pressure, velocity and temperature. This method can make the convergence process steady and effectively avoid divergence. The physical phenomenon of the self-excited Rijke pipe was analyzed. Moreover, the mechanisms on the Rijke pipe＇s self-excited oscillation were explained. Based on this method, comparative researches on the acoustic characteristic of the Rijke pipe with different size and different shape of nozzle were performed. The simulation results agreed with the experimental data satisfactorily. The results show that this numerical simulation can be used to study the sound pressure of nozzle for the engineering application of Rijke pipes.     

Reactive Ion Etching as Cleaning Method Post Chemical Mechanical Polishing for Phase Change Memory Device

In order to improve nano-scale phase change memory performance, a super-clean interface should be obtained after chemical mechanical polishing （CMP） of Ge2Sb2Te5 phase change films. We use reactive ion etching （RIE） as the cleaning method. The cleaning effect is analysed by scanning electron microscopy and an energy dispersive spectrometer. The results show that particle residue on the surface has been removed. Meanwhile, Ge2Sb2Te5 material stoichiometric content ratios are unchanged. After the top electrode is deposited, currentvoltage characteristics test demonstrates that the set threshold voltage is reduced from 13 V to 2.7V and the threshold current from 0.1 mA to 0.025 mA. Furthermore, we analyse the RIE cleaning principle and compare it with the ultrasonic method.     

Two-Dimensional Laguerre--Gaussian Asymmetric Soliton Family in Strongly Nonlocal Media

We demonstrate the existence of a broad class of higher-order Laguerre Gaussian asymmetric spatial optical solitons in strongly nonlocal nonlinear media. Furthermore, we discuss specific values （q = 0） of the modulation depth parameter for different rational values of the topological charge in detail. Our results show that higherorder asymmetry spatial sofiton family can exist in various forms, such as two-dimensional defect haff-solitons, asymmetric single-layer and multi-layer necklace solitons.     

Remote Generation of Entanglement for Individual Atoms via Optical Fibres

The generation of atomic entanglement is discussed in a system that atoms are trapped in separate cavities which are connected via optical fibres. Two distant atoms can be projected to Bell-state by synchronized turning off of the local laser fields and then performing a single quantum measurement by a distant controller. The distinct advantage of this scheme is that it works in a regime where Δ≈κ〉〉g, which makes the scheme insensitive to cavity strong leakage. Moreover, the fidelity is not affected by atomic spontaneous emission.