Target tracking in infrared imagery using a novel particle filter

To address two challenging problems in infrared target tracking, target appearance changes and unpre- dictable abrupt motions, a novel particle filtering based tracking algorithm is introduced. In this method, a novel saliency model is proposed to distinguish the salient target from background, and the eigenspace model is invoked to adapt target appearance changes. To account for the abrupt motions efficiently, a two- step sampling method is proposed to combine the two observation models. The proposed tracking method is demonstrated through two real infrared image sequences, which include the changes of luminance and size, and the drastic abrupt motions of the target.     

Lattice dynamics of room temperature orthorhombic SrHfO3

The lattice dynamics of room temperature orthorhombic phase of SrHfO₃ has been computed, using density functional perturbation theory. The full set of zone center phonon frequencies and infrared reflectivity spectra were reported, providing benchmark theoretical results for the interpretation of future experimental phonon measurements. It is found that the static dielectric constant is relatively anisotropic. This anisotropy has been discussed in relationship to the oscillator strengths and contributions of the lowest IR active modes.     

Pyrolysis oil from fast pyrolysis of maize stalk

Maize stalk was fast pyrolysed at temperatures between 420 °C and 580 °C in a fluidized-bed, and the main product of pyrolysis oil was obtained. The experimental results showed that the highest pyrolysis oil yield of 66 wt.% was obtained at 500 °C for maize stalk. Chemical composition of the pyrolysis oil acquired was analyzed by GC–MS and its heat value, stability, miscibility and corrosion characteristics were determined. These results showed that the pyrolysis oil could be directly used as a fuel oil for combustion in a boiler or a furnace without any upgrading. Alternatively, the fuel could be refined to be used by vehicles.     

乙酸稀土盐催化缩聚合成聚(对苯二甲酸乙二酯-co-己二酸乙二酯)

合成了一系列乙酸稀土盐(乙酸钇,乙酸镧,乙酸钕,乙酸镝),作为单组分催化剂,采用熔融缩聚法催化对苯二甲酸二甲酯、乙二醇和1,6-己二酸的共缩聚反应,制备了芳香族脂肪族共聚酯——聚(对苯二甲酸乙二酯-co-己二酸乙二酯)(PETA).通过1H-NMR,SEC,DSC及力学性能测试表征了聚合物的序列结构,分子量及分布,热性能及机械性能.结果表明,乙酸稀土盐单组分可催化共缩聚反应,效果优良,能够合成高分子量和较窄分子量分布的共聚酯,共聚酯具有较高的拉伸强度和断裂伸长率.     

四氧化二氮微量水标准物质的研制

以四氧化二氮为原料,经预脱水、深度脱水和精馏等处理工艺制备了7种浓度的四氧化二氮微量水标准物质.两家实验室采用核磁共振方法对标准物质中的微量水含量进行定值分析.用方差统计方法对定值结果进行数据处理和不确定度评定.     

丙烯酰氯改性木质素模型物制备丙烯酸单体及聚合活性分析

以木质素模型化合物二氢丁香酚(DH)为原料,利用丙烯酰氯(AC)进行接枝改性制备丙烯酸二氢丁香酚酯(DH-AC)。采用傅里叶变换红外光谱(FTIR)、气相色谱-质谱联用仪(GC-MS)、核磁共振氢谱(1H-NMR)和凝胶色谱(GPC)等分析手段研究了丙烯酸二氢丁香酚酯的结构以及聚合活性。FTIR结果表明二氢丁香酚经过丙烯酰氯改性后,3 495 cm-1为酚羟基伸缩振动吸收峰完全消失,在1 762 cm-1处有新的酯基峰生成,同时在1 631和981 cm-1出现CC的特征吸收峰,表明丙烯酸酯官能团已成功接枝到二氢丁香酚上。1H-NMR分析结果显示DH-AC在δ=5.6的酚羟基质子峰完全消失,同时在δ=6.0,6.4和6.7出现了三个不同的质子峰,这主要是由于乙烯基CHCH₂结构的引入,该结果进一步证明目标产物丙烯酸二氢丁香酚酯结构的正确性。GC-MS结果表明目标产物丙烯酸二氢丁香酚酯的纯度为98.63%。GPC结果显示DH-AC在偶氮二异丁氰(AIBN)作为引发剂的存在下,DH-AC可以发生聚合反应,均聚物相对分子质量结果为：Mw(37400),Mn(23400),Mw/Mn=1.60,表明丙烯酸二氢丁香酚酯单体具有高的聚合活性。丙烯酸二氢丁香酚酯(DH-AC)的制备和性能研究为开发新型木质素基高分子材料奠定了理论基础。     

NO Adsorption on Ag/Pt(110)-(1×2) Bimetallic Surfaces: Unexpected Formation of Nitrite/nitrate Surface Species

NO adsorption on Ag/Pt(110)-(1×2) bimetallic surfaces at room temperature was inves-tigated by means of Auger electron spectroscopy, X-ray photoelectron spectroscopy and thermal desorption spectroscopy. An unexpected formation of nitrite/nitrate surface species on Ag/Pt(110)-(1×2) bimetallic surfaces is observed, then decompose at elevated tempera-tures to form N₂. However, such nitrite/nitrate surface species do not form on clean Pt(110) and Ag-Pt alloy surfaces upon NO exposure at room temperature. The formation of ni-trite/nitrate surface species on Ag/Pt(110)-(1×2) bimetallic surfaces is attributed to highreactivity of highly coordination-unsaturated Ag clusters and the synergetic effect between Ag clusters and Pt substrate.     

全氟壬烯氧基苯磺酸钠与烷基季铵盐的相互作用

通过六氟丙烯三聚体(全氟壬烯)氧基苯磺酸钠(C₉F₁₇OC₆H₄SO₃Na, OBS)与阳离子碳氢表面活性剂C_nNR[C_nH_2n+1N(CH₃)₃Br, C_nNM, n=8, 10和C_nH_2n+1N(CH₂CH₃)₃Br, C_nNE, n=8, 10, 12]复配, 研究了OBS与C_nNR的摩尔比、 C_nNR疏水链长及C_nNR亲水基团大小对此类阴、 阳离子碳氟-碳氢表面活性剂混合体系的临界胶束浓度(cmc)、 最低表面张力(γ_cmc)、 总饱和吸附量(Γ_tm)及极限分子面积(A_min)的影响. 结果表明, 通过与C_nNR复配, OBS的cmc和γ_cmc均大幅下降, 达到了全面增效的结果. 不同摩尔比的OBS-C₈NE混合体系中, 摩尔比为1:1时表面活性最好, cmc和γ_cmc均最小; 偏离等摩尔比时, OBS过量时混合体系的cmc小于C₈NE过量时混合体系的cmc, 但γ_cmc相差不大. 与单体系相比, OBS-C₈NE混合体系的Γ_tm明显增大、 A_min明显变小. OBS与不同疏水链长的C_nNE复配时, cmc的变化规律为C₈NE>C₁₀NE>C₁₂NE, 表明C_nNE疏水链长的增加能降低混合体系的cmc. 通过比较C_nNM和C_nNE(n=8, 10)的表面活性发现, 改变混合体系中C_nNR的亲水基团大小对混合体系的表面活性无明显影响.     

Periodic solutions and stability of a tethered satellite system

In this paper, several criteria on the existence of periodic solutions for a tethered satellite system (TSS) in an elliptical orbit, as well as the uniqueness of periodic solutions for the TSS in a circular orbit are presented on the basis of coincidence degree theory. In addition, the conditions on the global asymptotic stability of the equilibrium states for the TSS are also addressed in accordance with the Lyapunov stability theory and Barbashin–Krasovski theory.     

双脉冲注入式LD模块的红外能级寿命可见区测试系统

Er3+的4I_13/2能级寿命的长短对评估Er3+掺杂材料在光通讯波段的应用十分重要。基于980 nm双脉冲注入式LD激发下的Er3+激发态吸收上转换发光,测量在不同双脉冲时间间隔下的上转换红光发光强度,再根据上转换红光的发光强度随双脉冲时间间隔的变化关系,推导出了Er3+红外4I_13/2能级寿命的拟合公式,实现了红外能级寿命的可见区测量。因此,结合兼具时间间隔可调和同步脉冲取样的双脉冲注入式LD模块和光电倍增管(R2658),就可以实现所有Er3+红外能级寿命的测量,这是一种十分经济的微秒量级荧光寿命测试系统。