多层次二氧化硅材料的仿生矿化研究进展

系统地介绍了仿生合成二氧化硅(SiO2)材料的研究进展,综述了仿生合成SiO2材料的模板分子特点及体外模拟方法,阐述了阴离子的存在、浓度、种类以及人工合成模板基质的不同类型对SiO2的尺寸和形貌的影响,并提出了新的实验思路,即设计合成具有催化活性的稳定的聚氨基酸多肽,在温和条件下,利用这种聚氨基酸多肽作为模板矿化SiO2材料,从而设计合成出具有特殊结构和性能的无机SiO2材料,并将此仿生材料应用到生物催化、药物载体等各个领域。     

γ-吡啶甲酸及其同位素衍生物的谐性力场和振动光谱的从头计算研究

本文采用TEXAS分析梯度法从头计算程序, 以STO-4-21G基组计算了γ-吡啶甲酸的谐性力场和振动光谱。直接理论计算的谐性力场经由相关分子转移来的校正因子校正后, 得到的振动基频的预测值和固体样品红外光谱实验值之间的平均偏差为20cm^-^1(面内振动23cm^-^1, 面外振动11cm^-^1)。用这组校正因子得到的力场预测了γ-吡啶甲酸的两个同位素衍生物(-C^1^8O~2H和-C^1^6O~2D)的振动光谱, 所得同位素位移值与实验数据符合良好。对平面内振动的个别校正因子依据实验光谱进行了优化, 平面内振动的平均偏差降为15cm^-^1, 总的偏差为14cm^-^1。对预测中的偏差和某些基频的指认进行了讨论。     

离子排斥色谱法同时测定果汁中11种有机酸

 用离子排斥色谱法实现了对果汁中 11种有机酸 (草酸、柠檬酸、酒石酸、苹果酸、抗坏血酸、乳酸、琥珀酸、甲酸、乙酸、戊二酸、富马酸 )的分离测定。以 17mmol/L硫酸为淋洗液 ,样品在ICE ION 30 0离子排斥柱上分离后 ,用紫外检测器在 2 10nm处测定其中的有机酸。各组分质量浓度测定的相对标准偏差在 1.5 %～ 9.8% (n =10 )。     

Homomorphic partial differential equation filtering method for electronic speckle pattern interferometry fringes based on fringe density

Noise reduction is one of the most exciting problems in electronic speckle pattern interferometry. We present a homomorphic partial differential equation filtering method for interferometry fringe patterns. The diffusion speed of the equation is determined based on the fringe density. We test the new method on the computer-simulated fringe pattern and experimentally obtain the fringe pattern, and evaluate its filtering performance. The qualitative and quantitative analysis shows that this technique can filter off the additive and multiplicative noise of the fringe patterns effectively, and avoid blurring high-density fringe. It is more capable of improving the quality of fringe patterns than the classical filtering methods.     

聚合物基超疏水材料制备技术的研究进展

聚合物基超疏水材料由于制备工艺简单、制备方法多样,正逐步成为最主要的仿生疏水材料,为工农业生产和人们的日常生活带来极大的便利。文章综述了聚合物基超疏水材料制备技术的最新研究进展,介绍了国内外有关聚合物基超疏水材料的制备工艺和制备方法,包括模板法(生物模板法、多孔阳极氧化铝法、多孔CO2微球层模板法)、化学气相沉积法、蒸汽诱导相分离法、电纺法、激光和等离子刻蚀法等,并指出了今后超疏水材料将面临的挑战。     

叶绿素a分子在乙醇溶剂中的瞬态吸收研究

The excited state of Chlorophyll a is investigated by femtosecond transient absorption. The transient absorption spectra of Q band and By band of Chlorophyll a in ethanol have been observed. The fast kinetics of Chlorophyll a which exhibit two ultrafast components were also measured. The one is assigned to transient absorption of the inhomogeneously broadened ground state absorption spectrum, while the other is the response of the solvent to the change of the electron configuration in the excited state due to salvation dynamics of the polar solvent molecules. To understand the anisotropy of Chlorophyll a in ethanol, the anisotropy profile was also performed by 405 nm excitation and found that the anisotropy profile is 0.143. The possible combination of θda, θdb and η at excitation of By band has been simulated.     

叶绿素a分子在乙醇溶剂中的瞬态吸收研究

采用飞秒瞬态吸收方法研究叶绿素a分子在乙醇溶液的的激发态性质。观测到叶绿素a的Q带和B_y带的瞬态吸收谱。并且观测到了叶绿素a分子的两个超快动力学过程。认为一个来源于基态吸收谱的非均匀展宽,而另一个则来源于溶剂对于激发态分子结构变化的响应。同时,为了了解叶绿素a在乙醇溶剂中的各相异性,采用405nm激发叶绿素a分子得到了各相异性值为0.143,并通过模拟得到可能的θ_(da)、θ_(db)和η。