分析电镜Cliff-Lorimer 因子测量及薄标样标准化探讨

采用电子探针矿物标样,即均匀性和稳定性符合显微定量分析要求的国标样品,制备成适于分析电镜（ＡＥＭ）成分分析的薄样品,测量了一组Ｃｌｉｆ－Ｌｏｒｉｍｅｒ（ＣＬ）因子,考察了用不同型号的分析电镜分析时ＣＬ因子的变化,提出了仪器校正因子ＫＩ＝εＢ／εＡ,对原子序数小于２０的较轻元素其ＣＬ应考虑作ＫＩ校正;作者建议采用易于制成薄晶片的黑云母标样来统一不同分析条件下的ＣＬ因子,并应建立适于分析电镜定量分析的无机薄标样通用技术条件。     

分数傅里叶变换全息图及其在防伪中的应用

提出分数傅里叶变换全息图,讨论了它的性质。拍摄分数傅里叶变换彩虹全息图。基于其再现条件的特殊性,可建立一种新型的伪全息术。     

衍射光学二维激光扫描器设计制作研究

提出、设计并采用激光直写和反应离子刻蚀技术制作出一种新型的衍射光学纯相位型二维激光扫描器,并进行了系统参数的实验测试,其扫描角度为２５°×２５°,衍射效率为４１％。     

Research Progress of Natural Small-Molecule Compounds Related to Tumor Differentiation

Tumor differentiation is a therapeutic strategy aimed at reactivating the endogenous differentiation program of cancer cells and inducing cancer cells to mature and differentiate into other types of cells. It has been found that a variety of natural small-molecule drugs can induce tumor cell differentiation both in vitro and in vivo. Relevant molecules involved in the differentiation process may be potential therapeutic targets for tumor cells. Compared with synthetic drugs, natural small-molecule antitumor compounds have the characteristics of wide sources, structural diversity and low toxicity. In addition, natural drugs with structural modification and transformation have relatively concentrated targets and enhanced efficacy. Therefore, using natural small-molecule compounds to induce malignant cell differentiation represents a more targeted and potential low-toxicity means of tumor treatment. In this review, we focus on natural small-molecule compounds that induce differentiation of myeloid leukemia cells, osteoblasts and other malignant cells into functional cells by regulating signaling pathways and the expression of specific genes. We provide a reference for the subsequent development of natural small molecules for antitumor applications and promote the development of differentiation therapy.     

Electrochemical behavior of thiamine on a self-assembled gold electrode and its square-wave voltammetric determination in pharmaceutical preparations.

The electrochemical behavior of thiamine on a self-assembled electrode of L-cysteine (Cys/SAM/Au) has been investigated and Cys/SAM/Au can be used to detect thiamine using square-wave voltammetry (SWV). At pH 11.40 Britton-Robinson buffer, thiamine exhibits a well-defined anodic peak on Cys/SAM/Au. Under the optimized conditions, the anodic peak current of SWV was linear with the content of thiamine in the range of 1.1 x 10(-8) - 2.2 x 10(-6) mol/L; the detection limit was 5.5 x 10(-9) mol/L. The method was successfully applied to the determination of thiamine in pharmaceutical preparations.     

各向异性超常材料的偏振分离特性

提出了一种利用含有负介电常量和磁导率张量的各向异性超常材料实现偏振分离的方法。通过分析电磁波在无损耗各向异性超常材料中的传输性质以及透射率与入射角度的关系,分类比较了由不同符号的介电常量和磁导率张量组合而成具有不同波矢面的各向异性超常材料的偏振分离特性,比较结果表明波矢面为单叶双曲面和椭球双叶双曲面的各向异性超常材料的偏振分离特性强。前者可以实现入射波中的s分量和p分量中某一分量正折射,另一分量负折射,且在一定条件下可以同时全透射,从而实现大角度偏振分离。后者在一定条件下可实现入射波中的s分量和p分量某一分量全反射,另一分量全透射,从而实现偏振分离。最后,对从各向同性介质入射到这两种各向异性超常材料中的高斯光波的传输进行了模拟计算,结果表明这两种各向异性超常材料可以实现很好的偏振分离功能,有潜力成为新型的偏振分离元件。     

Modeling and optimizing of high-concentration erbium-doped fiber amplifiers with consideration of ion-clusters

Starting from the modeling of isolated ions and ion-clusters, a closed form rate and power evolution equations for high-concentration erbium-doped fiber amplifiers are constructed. Based on the equations, the effects of the fraction of ion-clusters in total ions and the number of ions per cluster on the performance of high-concentration erbium-doped fiber amplifiers are analyzed numerically. The results show that the presence of the ion-clusters deteriorates amplifier performance, such as the signal power, signal gain, the threshold pump power for zero gain, saturated signal gain, and the maximum gain efficiency, etc. The optimum fiber length or other parameters should be modified with the ion-clusters being taken into account for the amplifiers to achieve a better performance.     

Hardy-Riesz拓广了的Hilbert不等式的一个改进

Let {a_n} and {b_n}be any two sequences of non-negative numbers such that 01).Then Hardy-Riesz′s extension of the Hilbert inequality can be sharpened to the form     

低雷诺数下串列布置双圆柱涡激振动特性研究

基于四步半隐式特征线分裂算子有限元方法,对串列布置双圆柱双自由度涡激振动问题进行了数值模拟计算,并分析了间距比、剪切率、频率比以及折减速度4个参数对圆柱结构动力响应的影响.研究发现:不同固有频率比与剪切率对下游圆柱振动幅值影响较大,然而对上游圆柱振动幅值影响较小.上游圆柱在两个自由度方向达到最大值的折减速度不同,然而下...