考虑通货膨胀与最长顾客等待时间的变质性物品的库存模型

本文建立了一种考虑通货膨胀与时间价值的变质性物品的库存模型,在模型中允许短缺发生且拖后的需求速率与在缺货期间已经发生的缺货量有关.和已有相关模型的主要区别在于本模型把一个可重复的订货周期内的最大平均利润的净现值作为目标函数,且增加了在缺货期间最长顾客等待时间的限制,以确保库存系统拥有较高的服务水平.然后讨论了模型最优解的存在性与唯一性,并提供了寻求模型整体最优解的算法.最后用实例说明了此模型在实际中的应用.     

Existence of weak solution and semiclassical limit for quantum drift-diffusion model

The existence and semiclassical limit of the solution to one-dimensional transient quantum drift-diffusion model in semiconductor simulation are discussed. Besides the proof of existence of the weak solution, it is also obtained that the semiclassical limit of this solution solves the classical drift-diffusion model. The key estimates rest on the entropy inequalities derived from separation of quantum quasi-Fermi level.     

Synthesis and characterization of novel perfluorinated polyimides with 3D‐controlled structures for photonic applications

We have designed and synthesized novel perfluorinated polyimides with 3D controlled structure. At first, we successfully developed the new synthetic routes to diamines with pendant bulky perfluorinated aromatic units in a multi‐step synthetic procedure. Novel perfluorinated polyimides were prepared in a two‐step reaction in N‐methyl‐2‐pyrrolidinone (NMP) solution: The first step was for the synthesis of polyamic acids (PAAs) and the second reaction was for the imidization of PAA. The polymer yield was over 89% and the inherent viscosity of PAAs was in the range of 0.24–0.36 dL/g. The thin films were prepared by spin‐coating the PAA solution in NMP onto various substrates such as a Si wafer or a KBr pellet, dried at 80 °C and further cured at 230 °C. The resultant polyimides are thermally stable over 400 °C. The refractive index and birefringence of the resultant polyimides are 1.5858–1.6452 and 0.01–0.005, respectively. The refractive index of polyimide decreases with increasing the fluorine content. The copolymerization and the ether linkages into the backbone reduce the birefringence of polyimides. Surprisingly, the pendant ether linkage is not a crucial factor in reducing the polyimide birefringence. Their birefringence is comparatively very low, compared with that of previous polyimides. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1326–1342, 2006     

三种瓜环与4,4′-联吡啶及N,N′-二甲基4,4′-联吡啶盐酸盐相互作用的研究

以七元瓜环(Q[7])和新型椭圆型改性瓜环———对称四甲基取代六元瓜环(TM eQ[6])为主体,4,4′-联吡啶的盐酸盐(44)以及N,N′-二甲基4,4′-联吡啶的盐酸盐(dm44)为客体的主客体相互作用进行了考察.实验结果表明,Q[7]与客体44及dm44作用体系中,客体为了更有效地被主体Q[7]包结,在Q[7]内腔中呈倾斜状分布的几率最高.用核磁共振、循环伏安以及紫外吸收光谱对实验结果进行了印证和补充,验证了TM eQ[6]与客体44及dm44可发生较强的相互作用,形成一维的自组装超分子结构.核磁共振以及循环伏安方法的实验结果表明,没有观察到Q[6]与客体44及dm44的明显作用,而紫外吸收光谱方法证实,Q[6]与客体44确实存在一定的相互作用,比较主客体的结构特征,该作用体系也可能存在自组装的一维超分子结构等多种作用形式.     

Optical properties of In2O3 oxidized from InN deposited by reactive magnetron sputtering

Unintentionally doped and zinc-doped indium nitride (U-InN and InN:Zn) films were deposited on (0 0 0 1) sapphire substrates by radio-frequency reactive magnetron sputtering, and all samples were then treated by annealing to form In₂O₃ films. U-InN and InN:Zn films have similar photon absorption characteristics. The as-deposited U-InN and InN:Zn film show the absorption edge, ∼1.8-1.9 eV. After the annealing process at 500 °C for 20 min, the absorption coefficient at the visible range apparently decreases, and the absorption edge is about 3.5 eV. Two emission peaks at 3.342 eV (371 nm) and 3.238 eV (383 nm) in the 20 K photoluminescence (PL) spectrum of In₂O₃:Zn films were identified as the free-exciton (FE) or the near band-to-band (B-B) and conduction-band-to-acceptor (C-A) recombination, respectively.     

高分子阳离子絮凝剂用于炼油废水处理研究

用聚二甲基二烯丙基氯化铵型高分子阳离子絮凝剂处理炼油废水考察了险油和化学耗氧量的动态变化规律。对产生的浮渣性质及滤饼的成份进行了研究。并且与聚合铝的处理效果进行对照。研究结果表明，ＨＣＡ除油和化学耗管氧量的性能优于ＰＡＣ，ＨＣＡ产生的浮渣是ＰＡＣ的三分之一，而浮渣中的含油量则是ＰＡＣ的三倍。     

微粒大小及其分布的光电复合检测

叙述一种新的光电复合测量技术，它集ＣＣＤ摄像显示，微机信息采集与处理，光不投影放大，显微镜目视判读为一体，可对微粒大小及其空间分布实行多通道测量，观察和分析。     

冲击波处理的结晶MgO的化学分析正电子谱研究

冲击波处理的结晶ＭｇＯ的化学分析正电子谱研究＊张菊郑小明（杭州大学催化研究所，杭州３１００２８）常志向（抚顺石油化工研究院，抚顺１１３００１）关键词冲击波，化学分析正电子谱，结晶氧化镁，丁烯，脱氢冲击波是在介质中以超音速传播的压力脉冲．气体中的冲击波...     

多功能沸点仪的研究

本文提出了两种新型沸点仪——CP-Ⅰ型和CP-Ⅱ型沸点仪, 阐述了仪器各部分结构的设计思想和原理, 并对仪器的性能和各部分功能进行了较为完整的实验考核, 获得了预期的效果。