浑水中非均匀光场探测图像方法

分析了传统的水下观测和激光观测技术在能见度约为0.5~1.5 m的浑浊水域和0.2 m的特浑水域观测遇到的理论和技术上的局限性.叙述了一种非均匀光场集束光水下目标图像探测方法和系统,并在各种浑浊水质中进行其特性的试验.试验结果表明该系统基本上解决了浑浊水中的观测问题.     

A power law distribution in patients’ lengths of stay in hospital

The distribution of patients’ lengths of stay in English hospitals is measured by using routinely collected data from 11 years. It is found to be well approximated by a power law distribution spanning over more than three decades. To explain this observation, a theoretical resource allocation model is presented. It is based on iterative long-term scheduling of hospital beds, and its main assumption is that future beds are allocated preferentially. This represents a situation where different parts of the health care system compete for resources, with bargaining powers proportional to current resource levels.     

二次风率对分级进风燃烧室内湍流燃烧与NOx生成的影响

本文在分级进风燃烧室的热态实验装置上,测量了燃烧室内湍流燃烧的温度场和组分浓度场,研究了分级进风的流量比率即二次风率对燃烧及NOx生成的影响.得到了四组不同二次风率下燃烧室内气体温度和O2、CO2、CO与NO浓度的分布.     

Planar Line Processes for Void and Density Statistics in Thin Stochastic Fibre Networks

Using results for the distribution of perimeters of random polygons arising from random lines in a plane, we obtain new analytic approximations to the distributions of areas and local line densities for random polygons and compute various limiting properties of random polygons. Using simulation, we show that the lengths of adjacent sides of polygons generated by random line processes in the plane are correlated with ρ=0.616±0.001.     

Research of the planar optical fiber Bragg grating hydrophone probe

This paper presents the planar Fiber Bragg Grating （FBG） hydrophone probe sensing principle, and theoretically and experimentally researches the probe structure sensitivity, the receiving sensitivity frequency response characteristic and the acceleration response property. Planar sheet is made of stainless steel, its thickness is 0.15 mm, its diameter is 15mm, and the length of hollow circular shell is 20 mm. For this size of the structure, the probe structure sensitivity is up to 23 fm/Pa, which is about 7300 times of the value of the bare fiber. The resonance frequency is 6.5 kHz, and the amplitude-frequency curve of the receiving sensitivity response is relatively flat within the frequency range of 100 Hz to 5.5 kHz. The output yielded by one unit acceleration （1m/s2） is equivalent to （2.52 to 3.26 Pa） acoustic pressure acting output. This probe structure is easy to form FBG hydrophone array by multiplexing technique. The research shows that this planar structure not only can form FBG hydrophone probe, but also can constitute optical FBG laser hydrophone probe. The structure can realize different bandwidth, different range acoustic pressure measurement by adjusting the geometrical size of the sheet.     

新型4-氨基安替比林席夫碱的合成及对Cu2+的选择性识别

设计合成了一种新型安替比林-席夫碱衍生物M(4-氨基安替比林缩5-硝基水杨醛席夫碱),用IR、1H NMR及元素分析对其结构进行了表征。通过紫外光谱和荧光光谱研究了M对Cu2+的选择性识别作用。结果表明:M与Cu2+能够以1∶1的化学计量比形成配合物,结合常数为6.5×104L·mol-1;M和Cu2+的结合导致M在496 nm处的荧光猝灭,紫外可见吸收光谱红移,且M对Cu2+有较高的选择性,受常见离子的干扰较小。     

工程测量中光波干涉必须满足的几个条件

讨论了两列光波发生干涉现象的理想化条件和在实验中能否观察到干涉现象发生的操作性条件,推导了各种情况下的理论公式。从工程应用的角度出发,研究了检测仪器的响应时间T和光强分辨能力对观察光的干涉现象的影响,提出了观察光的干涉现象的第四个必要条件,对在各种情况下应用光的干涉现象有一定的指导作用。     

低能He~(2+)入射He原子转移电离实验中出射电子成像研究

利用反应显微谱仪对70keV He2+-He转移电离过程中的出射电子进行了成像,研究了出射电子的空间速度分布特征.结果表明:电子主要集中在散射平面内;在散射平面内,电子速度分布介于零与入射离子速度Vp之间(即前向出射)且在散射离子和靶核核间轴处有一极小值,呈现出典型的双峰结构.出射电子的上述分布特征可由出射电子波函数σ振幅和π振幅的干涉进行定性解释,σ振幅和π振幅对出射电子波函数的贡献与碰撞参数相关.在小碰撞参数下,π振幅的贡献更加明显;而在大碰撞参数下,σ振幅的贡献更加显著.     

碳量子点/曙红Y比率型荧光探针测定L-抗坏血酸

以天然生物质去皮的蓖麻为碳源,采用一步水热法合成了荧光性能优良的绿色荧光蓖麻碳量子点(CO-CQDs),对其形貌和发光性能进行了表征。通过将该CO-CQDs与荧光极强的卤代荧光素染料曙红Y(EY)复合,二者可形成荧光发射峰相距较远的新型CO-CQDs/EY复合物。在pH=4.00的Na₂HPO₄-柠檬酸缓冲溶液中,在320 nm的激发波长下,CO-CQDs/EY复合物于405 nm和540 nm处显示出两个独立的荧光发射峰。在该体系中加入Cr(Ⅵ),405 nm和540 nm两处的荧光信号均显著猝灭。L-抗坏血酸(L-ascorbic acid,AA)的加入可使复合物于540 nm的荧光信号恢复,而405 nm处的荧光强度基本不变。据此建立了一种以CO-CQDs/EY复合物为比率型荧光探针测定AA的新方法。实验测定了荧光信号恢复的最佳条件和影响荧光恢复的因素,初步探讨了反应机理。在优化的实验条件下,该探针于540 nm/405 nm两处的荧光强度比值与AA的浓度在5.0×10^-8～4.0×10^-6 ...     

Single top partner production in the tZ channel at eγ collision in the littlest Higgs model with T-parity

Introducing the top partner is a common way to cancel the largest quadratically divergent contribution to the Higgs mass induced by the top quark. In this work, we study single top partner production in the tZ channel at eγ collision in the littlest Higgs model with T-parity(LHT). Since it is well known that polarized beams can enhance the cross section, we analyze the signal via polarized electron beams,and photon beams. we have selected two decay modes for comparison, based on the leptonic or the hadronic decays of the W and Z from the top partner. We then construct a detailed detector simulation, and choose a set of cuts to enhance signal significance. For mode A(B), the capacity for exclusion in this process at s~(1/2)=3TeV is comparable to the current experimental limits with L=1000(500) fb~(-1). If the integrated luminosity can be increased to 3000 fb~(-1), the top partner mass+mTcan be excluded up to 1350(1440) GeV at 2σ level. We also considered the initial state radiation effect, and find that this effect reduces the excluding ability of the eγ collision on the the top partner mass by approximately 10 GeV. Moreover, the ability to exclude the LHT parameter space at eγ collision complements the existing research.