电磁感应透明的非线性理论

考虑双激发态三能级原子系统，探讨了该系统小电磁感应透明的非线性理论。得到由于探测场非线性项的影响，尽管此时介质对探测光的透明依然存在，但是介质的色散率减小，从而使得探测光在介质中传播时，其群速度变大。     

Mos: A multicomputer distributed operating system

This paper describes the goals and the internal structure of MOS, a Multicomputer distributed Operating System. MOS is a general-purpose time-sharing operating system which makes a cluster of loosely connected independent homogeneous computers behave as a single-machine UNIX system. The main goals of the system include network transparency, decentralized control, site autonomy and dynamic process migration. The main objective in the design of the system was to reduce the complexity of the system, while maintaining good performance. The internal structure of the system can be characterized by modularity, a high degree of information hiding, hierarchical organization and remote procedure calls.     

相干二能级原子系统的自感应透明

本文讨论相干脉冲在共振相干二能级原子系统传播时，所产生的自感应透明现象，并获得了推广的面积定理以及椭圆余弦函数型稳态脉冲。     

氧化程度对羧酸型两性淀粉性能的影响

氧化型两性淀粉是一种新型的两性淀粉,同时包含羧基和阳离子基团。其制备采用两步法,先将淀粉阳离子化,再将阳离子淀粉氧化。阳离子淀粉最佳制备工艺为:淀粉乳浓度35%,醚化剂的用量为5%,pH11.6,反应先在50℃活化2h,再降温到45℃反应8h。通过添加不同量的NaClO到阳离子淀粉中制得羧基含量不同的两性淀粉,所得淀粉洁白,糊透明度高,稳定性强,凝沉性弱,热糊粘度也较阳离子淀粉明显下降,且这些性能均随羧基含量的增加而增强。     

Polymerization of fluoroacrylate and guar gum copolymer as a new pretreatment paste for ink‐jet printing of polyester

A novel pretreatment paste containing fluoroacrylate copolymer and modified Guar Gum was carried out on the polyester fabric to provide partial water repellency and printability after inkjet printed with water‐based disperse dye inks. The stable fluorinated pastes were prepared via miniemulsion polymerization of fluoroalkyl acrylates, styrene, 2‐ethylhexyl acrylate, and modified guar gum in the presence of AIBN as initiator, CTAB and polyoxyethylene polyaryl ether as surfactants under suitable reaction conditions. In the analysis of monomer conversion and particle size, the highest polymerization rate with smallest particle size was obtained with increasing concentration of surfactants and initiator but the decreasing degree of substitution of guar gum to imply stronger interactions between fluoroacrylate monomers, hydroxyl groups of modified guar gum and EO units of nonionic surfactants. The 30% of stock fluorinated paste with urea concentration of 6% provided the prints with highest K/S value, satisfactory edge acuity and least color difference between front and back sides of the fabric to show more transparency. The rating 80 of water repellency tested on the best treated polyester fabric demonstrated stain proof properties after sprayed with water and dried. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Polypropylene/linear low‐density polyethylene blends: Morphology,crystal structure,optical, and mechanical properties

The morphology, crystal structure, crystallization behavior, optical, and mechanical properties of isotactic polypropylene (iPP) blended with metallocene linear low‐density polyethylene (mLLDPE) and Ziegler–Natta linear low‐density polyethylene (zLLDPE), with and without nucleating agents, were investigated. The correlation between the structures and optical properties was investigated. The addition of linear low‐density polyethylenes (LLDPEs), nucleating agents, and poly(ethylene‐co‐octene) (POE) had little influence on the crystal form of the iPP. The growth along the b axis was favorable in the presence of nucleating agents and LLDPEs. The LLDPEs led to much finer crystal morphologies, and the nucleating agents further prohibited spherulite formation; consequently, light scattering from the bulk crystalline structure was reduced. In all blends, biphase morphology was observed, and POE could improve the adhesion between the iPP and mLLDPE. After blending with LLDPEs, the haze and stiffness decreased, and the gloss increased. mLLDPE enhanced the toughness whereas zLLDPE had a slight influence on it. The nucleating agents decreased the haze, increased the gloss more, and ameliorated the stiffness; however, they changed the toughness little. POE increased the toughness of the blend significantly, accompanied by a much lower haze, higher gloss, and almost the same stiffness. When the concentration of 1,3 : 2,4‐bis(3,4‐dimethyl‐benzylidene sorbitol) exceeded 0.25 wt %, the optical properties and mechanical properties leveled off. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

辽宁地区水平面年总太阳辐照量的多元线性回归估算研究

太阳辐照量数据在太阳能热利用中具有关键作用,为了较准确得到辽宁省内7个无据可查的城市的水平面年总太阳辐照量,本文在对影响水平面年总太阳辐照量的多种因素进行分析的基础上,结合其它相关已知信息,建立了由城市的纬度、海拔和年日照时数构成的多元线性回归模型,并利用与待求数据城市处于同一大气透明度分区的国内49个已知各项数据的城市作为回归样本,从而获得具体的回归方程.误差分析结果表明,此时最大相对误差可控制在±6.8%以内.另外,还利用太阳辐照量估算值与回归用样本数目的变化关系曲线,对省内各城市的太阳辐照情况进行了聚类分析,结果表明,此时可将估算值的参考误差缩小至±2.2%.     

Investigation on electromagnetically induced transparency and slowdown of group velocity in an Eu3+:Y2Si05 crystal

Electromagnetically induced transparency (EIT) and slowdown of group velocity (SGV) in Eu3+: Y2SiO5 were investigated by using density matrix equations of the interaction between light and matter and their numerical solutions. The relationship of the probe transmission with different probe detuning and coupling Rabi frequency was obtained. The influence of inhomogeneous line width on electromagnetically induced transparency and slowdown of group velocity were analyzed. Such transparency was restrained when inhomogeneous line width increased. The center transmission did not homogeneously change with an increase in ion-doped concentration. There is an optimal concentration which can make the electromagnetically induced transparency significant. It is evident that the group velocity of the probe has a minimum value for a certain level of coupling field strength.     

电磁诱导透明中探测光量子噪声的研究

首先研究了处在热平衡条件下的A型三能级原子与环境(热辐射场)的涨落耗散,利用马尔科夫近似下的系统 - 源相互作用理论精确推导出A型三能级原子衰减态密度矩阵元的演化方程组.在此基础上进一步研究了热平衡稳定态.最后利用全量子理论对光场失谐时电磁诱导透明中探测光的量子噪声进行了研究.结果表明量子噪声主要来源于激发态的原子态密度以及驱动光的失谐量,因此在冷原子系统中实现EIT并且减少驱动光的失谐量将是控制量子噪声的关键.