Mechanisms of femtosecond laser-induced damage in magnesium fluoride

We studied the single-shot damage in magnesium fluoride irradiated by 800 nm femtosecond (fs) laser. The dependence of damage thresholds on the laser pulse durations from 60 to 750 fs was measured. The pump-probe measurements were carried out to investigate the time-resolved electronic excitation processes. A coupled dynamic model was applied to study the microprocesses in the interaction between fs laser and magnesium fluoride. The results indicate that both multiphoton ionization and avalanche ionization play important roles in the femtosecond laser-induced damage in MgF₂.     

沥青混合料蠕变柔量的一种实用模型及其应用

通过分析沥青混合料加载时的“固结效应”和卸载时的“永久变形”等流变学特征,提出了一个较为实用的流变学模型,并给出了模型参数的确定方法,该模型参数数目可多可少,且能满足Blotzmann叠加原理,可应用于应力随时间变化以及其它各种复杂应力状态的情况。     

On the minimal periodic solutions of nonconvex superlinear Hamiltonian systems

This paper proves a multiplicity result for the minimal periodic solutions of Hamiltonian system under a superquadratic hypothesis on H weaker than the Ambrosetti-Rabinowitz-type condition. We also define a class of homogeneous functions, that are more general than the classical ones, and prove the Rabinowitz's conjecture in the case of H satisfying such new homogeneity.     

Igepal CO系列表面活性剂溶致液晶的结构特性

对壬基酚聚氧乙烯醚（IgepalCO）系列表面活性剂,生成何种溶致液晶与其EO基团数n有关,而在何浓度范围内生成溶致液晶则与生成溶致液晶的最低水含量及最大水增溶量有关．EO基团数n小于10时,生成层状液晶,n大于10时则生成六角状液晶,层状液晶两亲双层内,水与表面活性剂的最低摩尔比rmin和最高摩尔比rmax随EO基团数n增加分别是非线型增加与线型增加,在IgepalCO520（n＝5）中加入IgepalCO710（n＝10．5）,对层状液晶的生成无显著影响,在IgepalCO710中加入IgepalCO520,则对六角状液晶的生成产生显著影响,出现了六角状液晶向层状液晶的转变。     

典型表面活性物质在汞、镉汞齐和铅汞齐电极上的吸附行为

本文采用DD-1型电镀参数测试仪,测定了汞、镉汞齐和铅汞齐电极在1MKCl的基底溶液中,四下基碘化铵等十二种典型有机表面活性物质在三种电极上的脱附电位。由于镉汞齐和铅汞齐电极的阳极溶解电位比较负,未观测到F^-、Cl^-、Br^-离子的吸附现象。I^-离子及同一有机表面活性物质在三种电极上的吸附活性顺序为:Hg>Pb(Hg)>Cd(Hg)。测试结果表明:同浓度的同一种表面活性物质,在三种电极上的脱附峰电位值之差小于10mV。反映了镉汞齐和铅汞齐电极在脱附峰电位时的表面性质接近于纯汞。     

B-积分的Denjoy型定义

该文在Rπ空间中定义了一种Denjoy型非绝对积分,证明了这种Denjoy型积分与B-积分等价,从而给出了B-积分的Denjoy形式．     

石英玻璃中5.0 eV吸收带的起源

从吸收强度的角度出发研究石英玻璃中５．０ｅＶ光吸收带的起源。利用实验和理论给出的非驰豫氧空位缺陷态的能级,并以第一原理计算得到的石英玻璃导带电子态密度为基础,计算了５．０ｅＶ线性吸收系数。理论结果与实验结果符合得比较好,人而支持了非驰豫氧空位缺陷态是石英玻璃中５．０ｅＶ光吸收带的起源的观点。     

表面活性剂和助表面活性剂对镍的缓蚀作用

在ＨＣｌ水溶液中,三种典型的表面活性剂（ＣＴＡＢ、ＳＤＳ和Ｔｒｉｔｏｎ Ｘ－１００）对镍均有缓蚀作用,其缓蚀效率、腐蚀活化能的大小顺序是：ＣＴＡＢ〉Ｔｒｉｔｏｎ ｘ－１００〉ＳＤＳ。助表面活性剂正丁醇可作为缓蚀调节剂,其加入可控制金属镍在ＨＣｌ水溶液中的腐蚀速率。金属镍在各介质中腐蚀速率的顺序为ＨＣｌ（ａｑ）〉知性剂＋丁醇＋ＨＣｌ（ａｑ）〉表面活性剂＋ＨＣｌ（ａｑ）〉表面活性剂＋丁醇（ａｑ）〉表面     

飞秒激光对高反膜的破坏及其超快动力学过程

研究了800nm飞秒激光照射下45°高反膜ZrO2-Si O2的破坏及其超快动力学过程。利用原子力显微镜和扫描电镜观察了材料的烧蚀形貌,测量了破坏阈值与脉冲宽度、烧蚀深度与脉冲能量的依赖关系。随着脉冲宽度从50fs增加到900fs,其烧蚀阈值从0.35J/cm2增加到1.78J/cm2。烧蚀深度与激光能流密度近似成对数关系。当激光强度略高于烧蚀阈值时,材料很快被烧蚀到几百纳米,烧蚀深度表现出明显的层状特性。同时,利用建立的抽运探针实验系统,测量了高强度抽运脉冲作用下材料对探针光的反射率随延迟时间的变化,揭示了薄膜烧蚀的超快动力学过程。实验结果表明高反膜表层的材料对烧蚀特性有重要影响。     

Investigation of Coculture of Human Adipose-Derived Stem Cells and Mature Adipocytes

The purpose of this study was to evaluate the differentiation potential of human adipose-derived stem cells (hADSCs) into adipocytes by coculturing them with human mature adipocytes. The transwell culture system was utilized for indirect coculture of hADSCs and human mature adipocytes at four different hADSCs-to-mature adipocytes ratios, i.e., 1:5, 1:1, 2:1, and 5:1. After 8?days of coculture, the Oil Red O and Trypan Blue stainings were performed for the evaluation of adipogenic differentiation of hADSCs. In addition, flow cytometric analysis and Hoechst 33342/PI double staining were performed after 20?days of coculture. The Oil Red O and Trypan Blue stainings showed that hADSCs with high viability could not differentiate into mature adipocytes after 8 or 20?days of coculture. However, flow cytometric analysis indicated that CD105 expression of hADSCs decreased after 20?days of coculture. These results indicated that hADSCs cocultured with human adult adipocytes could not successfully differentiate into adipocytes.