表阿霉素及其相关物质在反相离子对色谱中的色谱行为

以表阿霉素及其6种相关物质为研究对象,系统评价了其在反相离子对色谱模式下的色谱行为.分别考察了流动相中有机相种类、有机相比例、水相中离子对试剂浓度、pH值对表阿霉素及其相关物质的影响.结果表明,使用乙腈作为有机相洗脱能力及分离效果优于甲醇,保留时间随乙腈比例增大而减小;随着离子对试剂十二烷基硫酸钠浓度增加,杂质阿霉素酮及柔红霉酮几乎无影响,其他5种物质保留时间增加.同时,表阿霉素及其杂质的保留行为受流动相pH值影响较大,当pH不高于4时可获得较好的分离效果.通过对表阿霉素及其相关物质反相离子对模式下的保留行为进行了系统的评价和定量描述,研究结果将有助于该类化合物液相色谱分离方法的发展.     

LSSC内物流服务集成商管理策略对提供商安全生产行为的影响研究

考虑由“功能型物流服务提供商—物流服务集成商—客户”构成的物流服务供应链(Logistics Service Supply Chain, LSSC),针对链内提供商安全生产问题的动态性与复杂性，探究集成商不同管理策略对提供商安全生产行为的影响。采用计算实验方法，抽象模拟出二者在选择与合作阶段的交互活动，分别进行集成商订单配置决策中安全因素权重、安全生产考评标准、安全风险抵押金对提供商安全生产行为的影响实验。研究结果表明：在客户具有安全偏好情况下，集成商通过合理的订单配置决策可实现提供商安全生产水平与自身收益的协同提升；当安全生产考评标准超过提供商可接受阈值时，其安全生产水平反而将会降低；收取安全风险抵押金可使提供商安全生产水平有所提高，但效果有限。     

Photoluminescence of Nanoporous GaN Films Prepared by Electrochemical Etching

Nanoporous （NP） CaN is prepared by electrochemical etching on a CaN epilayer grown on a sapphire substrate by metal-organic chemical vapor deposition. Scanning electron microscopy reveals that the average pore diameter and inter-pore spacing are approximately 25 and 45 nm, respectively. The photoluminescence （PL） spectra show that in contrast to the initial as-grown CaN epilayer, the NP CaN exhibits a high near-band-edge UV intensity, significant relaxation of compressive strain, and a lower yellow luminescence intensity. Both the line shape and line width of the PL spectra are almost the same for these two samples. The high quality of the NP CaN can be explained by the enhancement of the PL extraction efficiency and the decrease of impurity and defect density after etching.     

纳米流控能量吸收耗散系统

基于纳米流控行为设计的新一代能量吸收耗散系统(nanofluidic en-ergy absorption system,NEAS)将会比传统吸能材料具有更高的能量吸收密度,而且还可以重复使用,特别是在小体积应用环境下具有显著的优势.本文从实验和计算模拟两方面综述了目前关于NEAS能量吸收耗散行为的最新研究进展,其中实验研究主要包括准静态压缩和动态压缩测试,计算模拟研究主要是采用基于经验势的分于动力学模拟方法.通过准静态压缩实验,可以测量NEAS模型的载荷–位移关系曲线,从而获得NEAS模型的临界渗透压强,了解卸载后系统是否能够恢复到加载前的状态(即是否可以重复使用),井通过载荷–位移关系曲线下面积估算NEAS模型的吸能密度;通过动态压缩实验可以测量NEAS模型对脉冲载荷的缓冲保护作用,主要体现为降低脉冲载荷幅值和扩展脉冲宽度.计算模型研究可以明确给出NEAS对外载荷的微观响应,从而可以准确了解NEAS的能量吸收耗散机制以及吸能密度的主要影响因素.本研究可以帮助我们全面了解NEAS的研究进展,为NEAS的设计与优化提供重要指导.     

连续Josephson结系统解的长时间行为

讲座了超导中连续Josephson结系统解的渐近行为，利用先验估计证明了当时间趋于无穷时解收敛于对应稳态问题的解。     

一类Euler方程解的渐近行为

给出了一类Ginzburg-Landau型泛函的极小元所满足的Euler方程的解的某些弱收敛性质。     

Bifurcations and the penetrating rate analysis of a model for percussive drilling

In this paper, we investigate a low dimensional model of percussive drilling with vibro-impact to mimic the nonlinear dynamics of the bounded progression. Non- holonomity which arises in the stick-slip caused by the impact during drilling fails to be correctly identified via the classical techniques. A reduced model without non-holono- mity is derived by the introduction of a new state variable, of which averaging technique is employed successfully to detect the periodic motions. Local bifurcations are presented directly by using C-L method. Numerical simulations and the penetrating rate analysis along different choices of parame- ters have been carried out to probe the nonlinear behaviour and the optimal penetrating rate of the drilling system.     

Solitons with Periodic Behavior in an SBN：75 Photorefractive Crystat

We study the formation of spatial solitons in an SBN： 75 photorefractive crystal by a 532 nm continuous-wave laser beam. The output beam from the crystal cannot be compressed proportionally to the voltage of the applied electric field. Quasi-steady-state spatial solitons are formed instantaneously at a voltage of 900 V. Interestingly, the quasi- steady-state solitons exhibit a periodic behavior consisting of formation/broken/reformation cycles. If we increase the input intensity of the soliton beam but keep the same signal-to-background intensity ratio, the solitons stay for a longer time in the quasi-steady state and a longer period of soliton formation/broken/reformation cycle is also observed.