任意长圈覆盖指定的独立的点

An invariant σ2（G） of a graph is defined as follows： σ2（G） ：= min{d（u） ＋ d（v）｜u, v ∈V（G）,uv ∈ E（G）,u ≠ v} is the minimum degree sum of nonadjacent vertices （when G is a complete graph, we define σ2（G） = ∞）. Let k, s be integers with k ≥ 2 and s ≥ 4, G be a graph of order n sufficiently large compared with s and k. We show that if σ2（G） ≥ n ＋ k- 1, then for any set of k independent vertices v1,..., vk, G has k vertex-disjoint cycles C1,..., Ck such that ｜Ci｜ ≤ s and vi ∈ V（Ci） for all 1 ≤ i ≤ k.
The condition of degree sum σs（G） ≥ n ＋ k - 1 is sharp.     

Crystal Structure and Fluorescent Study of a Binuclear Europium（Ⅲ） Complex

A novel binuclear Eu（Ⅲ） complex [Eu2（dpa dioxide）2（NO3）4（bpdioxide）-（EtOH）] （dpa dioxide = di-2-pyridylamine N,N＇-dioxide, bpdioxide = 2,2＇-bipyridine N,N＇-dioxide） has been synthesized and it exhibits strong and sharp fluorescent emission at 614 nm under UV radiation of 245 nm at room temperature. X-ray structural determination indicates two independent Eu（Ⅲ） ions in the structure with different EuO8N and EuOgN environments. The compound crystallizes in the triclinic system, space group P1, with a = 10.8089（7）, b = 11.4670（8）, c = 17.1440（12） A, α = 92.834（2）, β = 93.854（3）, γ = 95.433（2）°, Z = 2, Dc = 1.876 g/cm3, V= 2107.3（2） A3, F（000） = 1168.0, the final R = 0.032 and wR = 0.086 for 6331 observed reflections with I 〉 2σ（I）.     

Strong labelings of linear forests

A （p, q）-graph G is called super edge-magic if there exists a bijective function f ： V（G） U E（G） →{1, 2 p＋q} such that f（u）＋ f（v）＋f（uv） is a constant for each uv C E（G） and f（Y（G）） = {1,2,...,p}. In this paper, we introduce the concept of strong super edge-magic labeling as a particular class of super edge-magic labelings and we use such labelings in order to show that the number of super edge-magic labelings of an odd union of path-like trees （mT）, all of them of the same order, grows at least exponentially with m.     

络合沉淀法合成纳米二氧化铈及其表征

由于其独特的物理化学性质,纳米二氧化铈是一种良好的无机紫外线屏蔽剂。纳米二氧化铈的制备方法有水热法、溶胶–凝胶法、均相沉淀法、电化学方法等,这些方法通常有操作流程复杂、周期较长等缺点。本文旨在探索一种操作简单,周期短的纳米二氧化铈制备方法。本文以氯化铈为铈源、柠檬酸为沉淀剂,采用络合沉淀法成功合成了纳米二氧化铈。通过元素分析计算了前驱体的组成,并采用比表面积测试、显微组织观察、紫外-可见光透过率曲线研究了纳米二氧化铈的物理性能、微观组织与紫外屏蔽性能的关系。研究结果表明,随着pH的升高,前驱体中Ce(H₂Cit)₃的比例下降,而Ce(OH)₃的比例上升,当pH = 6.5时,前驱体由CeCit和Ce(OH)₃组成;随着柠檬酸与Ce3+的摩尔比(n)的增加,前驱体中Ce(H₂Cit)₃的比例升高,而Ce(OH)₃的比例下降。当柠檬酸与Ce3+的摩尔比(n)为0.25、pH为5.5时,纳米二氧化铈在长波紫外线波段的平均透过率为4.42%,在中波紫外线波段的平均透过率为1.56%。良好的紫外屏蔽性能离不开纳米二氧化铈的物理性能和微观组织:比表面积的增大可以提高纳米二氧化铈的紫外屏蔽性能,当柠檬酸与Ce3+的摩尔比(n)为0.25、pH为5.5时,纳米二氧化铈的比表面积最大,为83.17 m2/g。纳米二氧化铈低指数晶面的晶面间距也影响着纳米二氧化铈的紫外屏蔽性能,在合理变化区间内,晶面间距越大,原子排列越密集,紫外屏蔽性能越好。由此得出这样的结论:络合沉淀法制备出的纳米二氧化铈具有优异的紫外屏蔽性能,但是,柠檬酸与Ce3+的摩尔比(n)不宜过大,pH不宜超过5.5。     

纳米LED在生物医学设备中的潜在应用

基于液相无机纳米晶体的发光二极管（LED）因为廉价且化学性质稳定而有望应用于生物医学诊断中,但由于难以实现紫外线发射,其研究一直未取得大的突破。     

2-nm narrow band pass filter in standard configuration evaporate coating machine

High sophisticated optical monitoring systems like the OMS 5000 from Leyboldoptics are commonly used in vacuum coating system to improve the capabilities and reliability of production processes concerning optical performance and repeatability optics. This letter describes a method to perform high end optical filters with additional backside blocking over a wide spectral range. The direct monitoring with intermittent measurement on a large area rotating substrate holder is used to facilitate a narrow band pass filter of 2-nm half bandwidth at 532 nm and high transmittance together with a complex blocking filter to retard disturbing radiation from the ultraviolet （UV） range to the near infrared range. The machine is an ARES 1350 coating system with basically standard configuration.     

From De Sitter Special Relativity and Snyder＇s Model to Complete Yang Model

The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder＇s model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantum levels, which are related by the proposed Killing quantization. It is actually a special relativity based on the principle of relativity of three universal constants （c, ρp, R）.     

宽温区内ZnO纳米线的CVD可控生长方法研究

以Zn粉为材料,采用CVD法在宽温区内可控生长ZnO纳米线.利用SEM对产物进行了微观分析,考察了反应温度与升温时间对ZnO纳米线形貌的影响.用ZnO纳米线制成光电导型紫外光探测器,并测试了该器件的性能,考察了所得ZnO纳米线的光电特性.研究工作表明:用CVD法制备ZnO纳米线时的反应温度不限于某一个特定值,而是常压下在419.5℃以上的温区内均可进行,该宽温区ZnO纳米线CVD合成法的关键在于优化和匹配生长温度与加热时间两个参数.对紫外光探测器的性能测试结果表明,ZnO纳米线具有良好的紫外光电响应特性.     

应用全波段CCD拍摄紫外光下金属类表面上汗液指印的研究

金属类客体上的汗液指印，在刑事技术工作中经常遇到，以前的拍照法都有一定的缺陷。全波段CCD出现后，就弥补了这个缺陷。实验中用全波段CCD在254nm短波紫外光下，通过不断变换打光方向拍摄金属类客体上的汗液指印，确定哪个打光方向下拍摄指印效果最好。通过实验印证了应用全波段CCD在紫外光下拍摄金属类客体上的汗液指印，是目前比较好的无损光学检验方法。     

Mechanisms of near-ultraviolet, nanosecond-pulse-laser damage in HfO2/SiO2- based multilayer coatings

The possible role of metal clusters and electronic defects in the near-ultraviolet, nanosecond-pulse-laser damage in HfO2/SiO2-pair - based coatings is analyzed using experimental results on absorption and damage in HfO2 monolayers with and without artificially introduced Hf nanoscale absorbers. These studies reveal a damage mechanism specific to HfO2/SiO2 pair combination comprised of a high-melting-point material （HfO2）, where absorption starts, and a lower-melting-point material （SiO2）, where absorption can be initiated upon reaching the critical temperature. Based on this analysis we discuss possible modifications to coating designs and desirable properties of high- and low-index materials that might lead to improve nanosecond, near-ultraviolet laser-damage performance.