Affinity genetic algorithm

Based on some phenomena from human society and nature, we propose a binary affinity genetic algorithm (aGA) by adopting the following strategies: the population is adaptively updated to avoid stagnation; the newly generated individuals will be ensured to survive for some generations in order for them to have time to show their good genes; new individuals and the old ones are balanced to have the advantages of both. In order to quantitatively analyze the selective pressure, the concept of selection degree and a simple linear control equation are introduced. We can maintain the diversity of the evolutionary population by controlling the value of the selection degree. Performance of aGA is further enhanced by incorporating local search strategies. Partially supported by a National Key Basic Research Project of China and by a USA NSF grant CCR-0201253.     

Optical characteristics of an afterglow extracted from an inductively coupled plasma

An inductively coupled plasma is extracted into a quartz vacuum chamber through an orifice to observe optical characteristics of the extracted afterglow. The Mach disk, the barrel shock and the zone of silence, which are familiar in supersonic molecular beam experiments with neutral gases, are clearly observed. Axial profiles of the emission of various lines are measured with a photodiode array spectrometer. Intensities of ionic lines as well as atomic lines are stronger at the Mach disk than in the zone of silence. The location of the Mach disk with varying chamber presure is in conformity with an experimental equation obtained in supersonic molecular beam experiments.     

(Eu2+,Nd3+)∶CaAl2O4的长余辉发光及机理的研究

采用高温固相反应法制备了Eu^2 ∶CaAl2O4、（Eu^2 ,Nd^3 )∶CaAl2O4，等系列材料。测量了其激发、发射光谱及余辉衰减曲线。分析了掺杂稀土离子对长余辉发光的作用。并对其发光机理进行了深入地探讨。     

战略导弹研制风险分析的仿真技术

本文以战略导弹研制风险分析为背景，对随机网络数据仿真技术原理进行了探讨，分析了曾广泛应用的仿真软件ＶＥＲＴＳＬＡＭ等的不足，并提出了改进方法，文中给出一种含信息流多层次综合网络仿真的构模框架，并用该构模框架对战略导弹风险分析的仿真模型作了研究。     

Temperature‐Correlated Afterglow of a Semiconducting Polymer Nanococktail for Imaging‐Guided Photothermal Therapy

Nanoparticles for photothermal therapy: Real‐time temperature monitoring is critical to reduce the nonspecific damage during photothermal therapy (PTT); however, PTT agents that can emit temperature‐related signals are rare and limited to few inorganic nanoparticles. We herein synthesize a semiconducting polymer nanococktail (SPN_CT) that can not only convert photo‐energy to heat but also emit temperature‐correlated luminescence after cessation of light excitation. Such an afterglow luminescence of the SPN_CT detects tumors more sensitively than fluorescence as a result of the elimination of tissue autofluorescence, while its temperature‐dependent nature allows tumor temperature to be optically monitored under near‐infrared (NIR) laser irradiation. Thus, SPN_CT represents the first organic optical nanosystem that enables optical‐imaging guided PTT without real‐time light excitation.     

CN chemiluminescence in N2 + CH4 Flowing afterglow at low temperatures

The spectra of flowing microwave post-discharge excited in N₂ and N₂ + CH₄(N₂ + C₂H₂) gas mixtures have been studied at low temperature (77 K). The molecular spectra of CN emitted by the collision-induced N + C and N + CH chemiluminescent reactions in the low-temperature afterglow system have been thoroughly investigated. The intensity of different CN (B²⁺-X²⁺) vibrational bands is very sensitive to low hydrocarbon concentration in nitrogen used as the working gas. Detection of hydrocarbon species has been demonstrated from concentrations of CH₄ and C₂H₂ in N₂ greater than 10¹⁰ molecules · cm^–3.     

大气氧谱带的实验研究

利用流动余辉装置,首次报道了金属镍表面催化基态氧原子O(3P)复合从而获得大气氧谱带O2 （b1Σg+→X3Σg-）的(0,0)电子跃迁光谱。并且对反应管壁去激活O2 (b1Σg+)的动力学过程进行了分析,间接证实了O2 (b1Σg+)的浓度在反应管中是非稳态的变化过程。最后对O2 (b1Σg+)的形成机理进行了简单的讨论。     

共掺La3+对Sr2SnO4∶Sm3+的余辉增强

研究了以La3+离子为辅助激活剂,对Sm3+掺杂的发光材料Sr2SnO4:Sm3+余辉性能的影响。采用传统的高温固相法合成Sr2SnO4∶Sm3+,La3+红色长余辉发光材料。利用X射线粉末衍射仪、荧光光谱仪、热释光剂量仪等手段对粉末样品进行了表征。分析结果表明,在1400℃得到了单相Sr2SnO4,Sr2SnO4∶Sm3+,La3+发光粉末有563、599和646 nm 3个发射峰,与Sm3+单掺杂的Sr2SnO4∶Sm3+相比,其光谱发射峰位没有明显变化。余辉亮度衰减曲线表明适量的La3+掺杂可以延长Sr2SnO4∶Sm3+的余辉时间。通过对热释光谱的分析,解释了双掺杂发光粉余辉性能增强的原因,La3+掺杂增加了更多适宜深度的陷阱(VSr″),可以有效存储光能,增强余辉的时间和强度。     

新型红色荧光粉NaLa_(0.7)(MoO_4)_(2-x)(WO_4)_x∶0.3Eu~(3+)的制备及发光性质研究

采用高温固相法合成具有余辉性能的发光材料NaLa_(0.7)(MoO_4)_(2-x)(WO_4)_x∶0.3Eu~(3+)(x=0,0.5,1,1.5,2)。用X射线衍射(XRD)和荧光光谱对样品的晶体结构和发光特性进行表征。测试结果表明,在900℃下烧结8 h所合成的NaLa_(0.7)(MoO_4)_(2-x)(WO_4)_x∶0.3Eu~(3+)样品为纯相Na La(Mo O_4)_2,样品可被近紫外光393nm和蓝光462 nm有效激发,其发射主峰位于615 nm处,属于Eu3+的5D0-7F2跃迁。Na La_(0.7)(Mo O_4)_(2-x)-(WO_4)_x∶0.3Eu~(3+)的发光强度随着W6+浓度的增加而增大,当W6+掺杂量x=1时发光最强,而后随W6+掺杂浓度的增加出现浓度猝灭现象。通过计算得到样品在393 nm和462 nm激发下的色坐标,当W6+的掺杂量x=1时,样品的红光色纯度最好。     

Accessing Tunable Afterglows from Highly Twisted Nonaromatic Organic AIEgens via Effective Through‐Space Conjugation

Nonaromatic, cross‐conjugated, and highly twisted luminogens consisting of acylated succinimides demonstrate aggregation‐induced emission characteristics along with tunable multicolor photoluminescence and afterglows in their single crystals. Effective through‐space conjugation among different moieties bearing n/π electrons promote the spin–orbit coupling and intersystem crossing and lead to diverse emissive clusters with concurrently rigidified conformations, thus allowing readily tunable emissions. Derived from it, the proof‐of‐concept application for advanced anti‐counterfeiting is illustrated. These results should spur the rational design of novel nonaromatic AIEgens, and moreover advance understandings of the non‐traditional intrinsic luminescence and the origin of tunable multicolor afterglows.