High-temperature stability multilayers for extreme-ultraviolet condenser optics

We investigate the thermal stability of Mo/SiC multilayer coatings at elevated temperatures. Transmission electron microscopy and x-ray diffraction studies show that, upon annealing, a thermally induced structural relaxation occurs that transforms the polycrystalline Mo and amorphous SiC layers in as-deposited multilayers into an amorphous Mo-Si-C alloy and crystalline SiC, respectively. After this relaxation process is complete, the multilayer is stable at temperatures up to 400 degrees C.     

Coexistence of Vortex Liquid and Solid in Rotating Bose-Einstein Condensate

No Heading We perform computer simulations for the Gross-Pilaevskii equation with a tiny damping in order to study the condensate wave-function in 3-D rotating Bose-Einstein condensate under the trapping potential. We find that the wave-function is divided into two kinds of phases in terms of its coherent feature. The first one is a coherent phase which is characterized by the static vortex lattice located close to the center of the trapping potential, and the second one is an incoherent one which lies outside the first coherent phase and shows vortex liquid like behaviors. The boundary between the two phases is quite sharp like the phase interface as seen in the first-order phase transition. This result suggests that the melting seen in type II superconductors spatially occurs in the rotating Bose-Einstein condensate since the wave-function amplitude decreases with departing from the center of the trap and its coherent feature is overcome by intrinsic fluctuations at a certain distance.PACS numbers: 03.75.Lm, 03.75.Kk, 74.25.Qt, 74.40.+k     

Wood and bark of some poplar and willow clones as fuelwood

Poplars and willows are widely used to produce biomass for energy. Calorific values of wood and bark, as well as for whole tree of Populus × euramericana (cl. I-214), Populus deltoides (cl.PE 19/66) and white willow Salix alba (cl.378) of different ages were determined. one- and 2-year-old rooted cuttings were grown in plantations with high planting density, in order to produce a high biomass yield per hectare. Mature trees in both species (poplar and willow) originated from the corresponding plantations; willow 14-year old, and poplar 12 years (cl.I-214) and 8 years (cl.PE 19/66). As the share of bark depends on the age of wood, calorific values were determined separately for bark and for wood. The share of bark (proportion of total weight) in 1- and 2-year-old rooted cuttings ranged between 18% and 27%, and in older trees it was from 10% to 15%. The higher heating values of oven dry poplar wood (calculated for the whole tree, based on the proportion of bark) were from 15,787 (cl. I-214 1-year old) to 24,275 kJ/kg (cl.I-214 2-year old). The average calorific values of willow wood (whole tree with bark) were from 16,169 (14-year old) to 22,572 kJ/kg (2-year old). It should be pointed out that the calorific value of wood is more favorable than that of bark, and the highest calorific values refer to 2-year-old trees.     

Time integrated detection of femtosecond laser pulses scattered by small droplets

Scattering of femtosecond laser pulses by small droplets has been measured and compared with predictions, yielding some interesting new applications for time integrated detection of the scattered field. The scattering intensity of integrated detection becomes monotonic with droplet size over large regions of scattering angle and morphology dependent resonances are surpressed, opening the way for particle sizing using the scattered intensity. Furthermore, the ripple structure no longer appears in the rainbow region of scattering, simplifying rainbow refractometry significantly. These scattering proporties of femtosecond laser pulses have been demonstrated in the laboratory using a novel Paul trap for levitating single droplets.     

红外热像仪外场性能测试系统

为了满足部队外场条件下进行红外热像仪技术性能检测的设备需求,设计一套红外热像仪外场性能测试系统。在现有几种典型的检测系统的产品基础上,通过等效条带图案的方法,预测热成像系统在多种概率下的可探测、识别和认清距离的数学模型,确定各种红外装备的检测修正因子,得到测试参数精确性能指标,并设计了红外热像仪外场性能测试系统的总体设计方案及实现的方法。实测数据分析表明：该测试系统在结构设计上有一定的创造性,可满足部队维修保障需求,具有应用价值。