环形障碍物-轴棱锥产生局域空心光束

提出一种产生局域空心光束(bottle beam)的新方法,它是在传统的轴棱锥底面上放置一个环形障碍物.平面波入射到带有环形障碍物的轴棱锥底面时,将在轴棱锥产生的最大无衍射距离内形成bottle beam,而在bottle beam的前后仍然保持无衍射贝塞尔光.通过变化障碍物大小及轴棱锥底角实现bottle beam尺寸的控制.利用衍射理论描述了平面波经带有环形障碍物的轴棱锥产生bottle beam的原理,分析和模拟了传输过程中不同位置的截面光强分布及整个过程的三维光强分布,并给出相关的实验结果.研究结果对bottlebeam的实际应用具有积极的意义.     

Advanced optical trapping by complex beam shaping

Optical tweezers, a simple and robust implementation of optical micromanipulation technologies, have become a standard tool in biological, medical and physics research laboratories. Recently, with the utilization of holographic beam shaping techniques, more sophisticated trapping configurations have been realized to overcome current challenges in applications. Holographically generated higher‐order light modes, for example, can induce highly structured and ordered three‐dimensional optical potential landscapes with promising applications in optically guided assembly, transfer of orbital angular momentum, or acceleration of particles along defined trajectories. The non‐diffracting property of particular light modes enables the optical manipulation in multiple planes or the creation of axially extended particle structures. Alongside with these concepts which rely on direct interaction of the light field with particles, two promising adjacent approaches tackle fundamental limitations by utilizing non‐optical forces which are, however, induced by optical light fields. Optoelectronic tweezers take advantage of dielectrophoretic forces for adaptive and flexible, massively parallel trapping. Photophoretic trapping makes use of thermal forces and by this means is perfectly suited for trapping absorbing particles. Hence the possibility to tailor light fields holographically, combined with the complementary dielectrophoretic and photophoretic trapping provides a holistic approach to the majority of optical micromanipulation scenarios.     

基于关键链方法的多项目共享人力资源均衡问题及其遗传算法

通过对多项目管理瓶颈的分析,结合关键链方法,设置了瓶颈缓冲,建立了基于关键链方法的多项目管理,为多项目管理提供了一种新的管理方法.将基于关键链方法的多项目管理方法应用于并行多项目共享人力资源冲突管理,建立了基于遗传算法的多项目共享人力资源均衡模型,为缓解多项目共享人力资源供求矛盾提供了一种具体的量化管理方法,并进行了算例分析,证明了模型的有效性、实用性.     

Semi-equivelar maps on the torus and the Klein bottle are Archimedean

If the face-cycles at all the vertices in a map on a surface are of same type then the map is called semi-equivelar. There are eleven types of Archimedean tilings on the plane. All the Archimedean tilings are semi-equivelar maps. If a map $X$ on the torus is a quotient of an Archimedean tiling on the plane then the map $X$ is semi-equivelar. We show that each semi-equivelar map on the torus or on the Klein bottle is a quotient of an Archimedean tiling on the plane.Vertex-transitive maps are semi-equivelar maps. We know that four types of semi-equivelar maps on the torus are always vertex-transitive and there are examples of other seven types of semi-equivelar maps which are not vertex-transitive. We show that the number of $\mathrm{Aut}\left(Y\right)$-orbits of vertices for any semi-equivelar map $Y$ on the torus is at most six. In fact, the number of orbits is at most three except one type of semi-equivelar maps. Our bounds on the number of orbits are sharp.     

TC2模型下底夸克对产生的研究

在顶色辅助的technicolor模型下, 计算了来自赝标哥得斯通玻色子和新规范玻色子对e⁺e^－→bb的截面贡献. 发现由technipions和新规范玻色子产生截面的修正足够小以至于可以忽略, 在合理的参数范围内, top pions起主要作用, 在质心能量√s=500GeV, 修正的最大值可以达到43%; 在√s=1500GeV, 最大的相对修正却只有3.1%. 这为我们在下一代直线对撞机实验中探测顶色辅助的technicolor模型下(TC2模型)提供了可行的方法.     

NaY沸石超笼中合成12-钼磷杂多酸

针对负载杂多酸催化剂在极性反应体系中活性组分易溶脱的难题, 用“瓶中造船(ship in the bottle)”的方法在NaY沸石超笼中合成了12-钼磷酸. 将机械混和的MoO₃晶体和NaY沸石在高温下焙烧, 使MoO₃在沸石表面高度分散, 以此复合物在磷酸水溶液中反应, 得到的固体样品用X射线衍射仪(XRD)、³¹P核磁共振谱(³¹P NMR)和红外光谱(IR)进行了表征, 并测试了其在醋酸和正丁醇的酯化反应中的催化性能. 结果表明, MoO₃质量分数为10%的MoO₃/NaY 中载体仍保持Y沸石的结构, 以此为原料合成的样品呈现出Keggin结构杂多酸的红外特征峰, 并且在核磁共振磷谱中杂多酸的化学位移峰向负值方向发生了较大程度的位移, 说明杂多阴离子与Y沸石羟基发生了强相互作用, 样品在醋酸与正丁醇的酯化反应中显示出了较高的催化活性和优异的重复使用性能. 这些充分说明在NaY沸石超笼中成功合成了12-钼磷酸.     

New Technology for Solid-state Polymerization of Polymers: Polyethylene terephthalate–Solid-state Polyaddition

This article introduces the new M&G technology for Solid state polyaddition (SSPA) of polyethylene terephthalate (PET). The new SSPA is characterized by the following: (1) It is based on a novel chemical process, SSPA. (2) It is suitable for high-performance polyesters. (3) It enables separate control of many different key properties of the polyester (molecular weight, rheology, crystallinity, etc.). This intrinsic flexibility has already been exploited to produce tailor-made polyesters suitable for most important applications in packaging and related fields. It is also a powerful tool for the upgrading of recycled PET. The SSPA reaction has a much faster kinetic than the standard solid-state upgrading process so that accordingly the intrinsic viscosity (I.V.) built up in the solid state is much faster than that of solid-state polycondensation. This raises the possibility of solid-state upgrading at lower temperatures, where standard solid-state polycondensation reactions are barely noticeable. The accelerating reactions used in this process could be utilized to de-bottleneck the existing production plants in order to attain greater productivity, more flexibility, lower costs and higher quality. © 1997 John Wiley & Sons, Ltd.     

The Elemental Profile of Beer Available on Polish Market: Analysis of the Potential Impact of Type of Packaging Material and Risk Assessment of Consumption

Twenty-five elements, including the most essential and toxic metals, were determined in fifty beer samples stored in cans and bottles by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Cold Vapor Atomic Absorption Spectroscopy (CVAAS) techniques. The packaging material was analyzed using the Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) technique. The control of the level of individual metals is necessary, not only to maintain the organoleptic properties of the product, but also to fulfill the standards regarding the permissible maximum concentrations. Metals can originate from different sources, including the brewing water, malt grains, hops, adjuncts, fruits, and spices. They may also come from contamination from the brewery equipment, i.e., vessels and tanks, including beer packing, storing and transporting (kegs, casks, cans). Discriminant analysis revealed that the differentiation of three types of beer (Lager, Ale, Craft) was possible, based on elemental concentrations, for the reduced data set after their selection using the Kruskal-Wallis test. The analysis of the impact of the packaging material (can or bottle) proved that when this parameter was used as a differentiating criterion, the difference in the content of Na, Al, Cu and Mn can be indicated. The risk assessment analysis showed that the consumption of beer in a moderate quantity did not have any adverse effect in terms of the selected element concentrations, besides Al. However, in the case of Al, the risk related to consumption can be considered, but only for the beer stored in cans produced from aluminum.     

基于图像处理的玻璃瓶口裂纹检测系统设计与实现

为了快速、准确地对玻璃瓶口裂纹进行无接触检测,基于图像处理技术设计与开发了一个玻璃瓶口裂纹检测系统。首先对获取的玻璃瓶口图像进行降噪与分割处理,并利用重心法获取玻璃瓶口圆心的粗定位,然后利用边界跟踪算法对玻璃瓶口进行边界跟踪,并通过 最小二乘拟合获取玻璃瓶口圆心的精确位置,最后利用深度优先遍历算法对裂纹点集进行聚群,从而实现对玻璃瓶口裂纹的检测。实验结果表明,该系统操作简单、效率高、抗干扰能力强,能满足实际使用的要求。     

产生不同类型局域空心光束的可拆式组合轴棱锥

提出一种产生尺寸可调局域空心光束的新型光学元件——可拆式组合轴棱锥,这种新型光学元件是在传统轴棱锥的中部沿其轴线方向贯通开设一圆孔,在圆孔内嵌设一第二轴棱锥组成。通过更换不同底角的第二轴棱锥(或第一轴棱锥),可形成不同尺寸的单个局域空心光束或周期性局域空心光束。从几何光学出发分析了产生局域空心光束的原理,计算了局域空心光束的相关参量。由衍射积分理论分析和模拟了新型光学元件的光强分布特性。几何光学和衍射理论所得分析结果基本吻合。