无人机载PolInSAR城区散射机制初步分析

极化干涉合成孔径雷达（PolInSAR）在城市遥感领域中扮演着重要角色。它能够提高图像的相干性并提高反演结果的精度,所以对于其散射机制的解释往往受到许多研究人员的关注。相关的研究多从极化分解的角度考虑,却少有人从散射中心高度方面进行分析。本文使用Ku波段无人机载极化干涉SAR系统,实现了使用无人机SAR系统对地面进行成像,比较了极化干涉最优分解与Pauli分解作用在不同人造目标时散射中心的关系。我们初步分析了极化干涉SAR的物理意义,并使用C波段的机载极化干涉SAR系统对结论进行验证。     

Effect of Low Energy Electron Exposure on Ion Scattering Spectroscopy

The effect of low energy electron (LEE) exposure on ISS, including on the sputter peak and scatter peak as well as on ion neutralization, has been investigated for different samples. Some new results are discussed.     

A New Triterpenoid from "Gualou-xiebai-baijiu-tang" Consisting of Fructus trichosanthis and Bulbus allii mtacrostemi

A new triterpenoid saponin was isolated by bioactivity-guided isolation from "Gualou-xiebai-baijiu-tang" consisting ofFructus trichosanthisi and Bulbus allii macrostemi. Its structure was determined as 3-O-β-D-galactopyranosyl-hederagenin 28-O-β-D-xylopyranosyl (1→6)- β-D-galactopyranosyl ester by means of chemical evidences and spectral analysis.     

Error of DIAL-measured Ozone Concentration and a Three-Wavelength Inversion Technique

Sensitivity of the error in the stratospheric ozone concentration measured by DIAL to the scattering property of the stratospheric aerosol is studied through both theoretical analysis and numerical experiment in this paper, and based on the sensitivity, a three-wavelength lidar inversion technique is proposed for a simultaneous determination of ozone concentration profile, aerosol backscatter coefficient profile and its size distribution in the stratosphere. It is found from the sensitivity study that there is a considerable effect of the stratospheric aerosol on accuracy of the ozone concentration solution. If the aerosol scattering is neglected, a large error of the solution can be obtained, especially when there is the stratospheric volcanic cloud, the error can be up to 100%. According to numerical experiments, a great improvement of the ozone concentration solution is obtained by using the present three-wavelenght inversion method.     

CHARACTERIZATION OF AMPHIPHILIC AND MICROPHASE SEPARATED GRAFT COPOLYMERS Ⅱ SURFACE CHARACTERIZATION AND IN VITRO BLOOD-COMPATIBILITY ASSESSMENT OF POLYSTYRENE-GRAFT-ω-STEARYLPOLY (ETHYLENE OXIDE)*

This paper reported the research results concerning the surface characterization ofpolystyrene-graft-w-stearyl poly(ethylene oxide) (PS-g-SPEO) by means of XPS,contactangle measurement and TEM, and its in vitro blood compatibility assessment by measuringthe plasma recalcification time (RT) and partial thromboplastin time (PTT). The XPSresults demonstrated that the surface and bulk composition of the PS-g-SPEO graftcopolymers differ remarkably from each other,and that SPEO component was constantlyenriched at the copolymer/air interface. Contact angle studies indicated that the surfacewater wettability can be adjusted effectively by changing the composition of the copolymer.PS-g-SPEO graft copolymers can undergo microphase separation as clearly illustrated byTEM photographs. The relationship between the surface properties of PS-g-SPEO graftcopolymer and its blood compatibility was also discussed.     

含氧膦结构的可溶性感光聚酰亚胺合成与表征

聚酰亚胺(PI)是一类综合性能优异的功能性材料,广泛应用于航天、航空及电子工业等领域[1].感光聚酰亚胺可以采用光刻工艺,大大简化了其应用加工程序[2,3],因而备受人们所青睐.含查尔酮结构的聚合物对UV辐射敏感度高和化学稳定性好,最近被广泛的研究和应用[4～7].主链含查尔酮结     

N-丙基-N-[2-(2,4,6-三氯苯氧基)乙基]-1H-咪唑-1-甲酰胺的合成

以2，4，6-三氯苯酚和1，2-二氯乙烷为初始原料，在相转移催化剂十六烷基三甲基溴化胺和弱碱性助剂三乙胺存在下合成了N-丙基-N-[2-(2，4，6-三氯苯氧基)乙基]-1H-咪唑-1-甲酰胺，其结构经元素分析,IR，^1H NMR分析证实。并对该合成路线的反应机理进行了讨论。     

高分子化学课程中若干论题的进展

高分子化学课程中下列五个论题被加以修正和补充:(1)1,2-二取代乙烯单体的聚合;(2)乙烯基单体聚合时的键连方式;(3)自由基聚合的自动加速;(4)引发转移和引发转移终止剂;(5)氢转移聚合和基因转移聚合。     

Y2O3, La2O3, Sm2O3对氧化铝瓷烧结及力学性能的影响

研究了3种稀土氧化物对氧化铝陶瓷烧结性能和力学性能的影响.结果表明 含Y2O3,La2O3,Sm2O3的添加剂促进了氧化铝瓷的烧结,提高了氧化铝瓷的力学性能.Y2O3和Sm2O3掺量为0.50%,La2O3掺量为0.75%时氧化铝瓷在1600或1620 ℃保温2 h烧结,相对密度达98.9%以上,强度超过439 MPa,断裂韧性达5.15 MPa·m1/2以上.微观结构分析表明,Y2O3,La2O3,Sm2O3抑止氧化铝晶粒生长,细化晶粒,使晶粒尺寸较均匀形成致密化结构.