基于Hyperion数据的耕地土壤有机质含量遥感反演

为了探究耕地土壤有机质含量与卫星影像光谱间的关系,确定土壤有机质的光谱特征,构建土壤有机质含量反演模型.利用Hyperion高光谱卫星影像和福建省三明市80个土壤调查样点分析数据,对土壤有机质与光谱指数相关性进行了分析;在提取特征光谱指数的基础上,分别基于敏感波段和特征指数建立线性模型和多元逐步回归模型.结果表明:土壤有机质含量在Hyperion高光谱782.95~813.48 nm波段具有良好的响应能力;反射率的一阶导数所建立的模型拟合效果最优,其R2为0.777,RMSE为5.31,验证模型有机质实测值与预测值的R2为0.809,表明它能够用于区域有机质含量的快速测定.     

Spectral reflectivity of lunar samples

Twelve rock chips and two samples of fines all have electronic absorption bands in diffuse reflected light between 0.32 and 2.5 micrometers. Major bands occur between 0.94 and 1.00 micrometer and at 2.0 micrometers, and arise from Fe(2+) in clinopyroxene and to a lesser extent in olivine. A band at 0.95 micrometer and other details of curve slope and shape for the lunar surface fines match McCord's telescopic curve for an 18-kilometer area that includes the Apollo-il site. Results confirm mineralogical predictions based on telescopic data and support the feasibility of obtaining mineralogical information by remote and in glass content. reflectivity measurements.     

干旱区土壤含水量光谱特征分析与反演

[目的]建立土壤含水量遥感监测模型。[方法]选取陕西省横山县作为研究区,以野外原位光谱测量数据和实验室内测得的土壤含水量为基础,进行高光谱数据处理,分析土壤含水量的光谱特征;对实测土壤光谱反射率进行倒数、对数、均方根及其一阶导数微分等光谱变化换,计算高光谱指数,并与土壤样本含水量进行相关性分析,筛选对土壤含水量敏感的光谱特征波段,利用多元线性回归分析建立土壤含水量监测模型。[结果]随着土壤含水量的增加,土壤光谱反射率呈减小趋势。土壤含水量与光谱指数的特征波段呈良好的线性关系,所有模型均通过了0.01水平的显著性检验。模型精度验证表明,预测值与实测含水量相关系数较高,特别是反射率倒数一阶微分模型,在0.01显著性水平下,相关系数为0.886。[结论]该研究建立的土壤含水量遥感反演模型可行有效,通过了有效性检验,在一定程度上可以用来反演研究区土壤含水量。     

黄尾鲴不同组织中LDH同工酶的研究

[目的]研究黄尾鲴不同组织的LDH同工酶。[方法]采用垂直板聚丙烯酰胺凝胶电泳技术和特异性染色方法对黄尾鲴的肝、肾、眼、心4种组织的LDH同工酶进行分析。[结果]酶谱的表达具有明显的组织特异性。酶带由3个基因座位(LDH-A、LDH-B、LDHC)编码,在4种组织中共检测到14条带,其中,心和肾7条带,眼6条带,肝14条带。在PAGE胶趋向阴极侧检测到6条肝脏组织所特有的LDH-C基因编码带。在各组织LDH酶带表达活性上,心中LDH-2、LDH-3和LDH-5表达占优势,肾中LDH-2、LDH-7和LDH-3表达占优势,肝中LDH-13、LDH-9和LDH-12表达占优势,眼中LDH-5、LDH-2和LDH-7表达占优势。[结论]该研究为丰富黄尾鲴遗传学基础研究、遗传育种种质标准的建立和种群生化遗传结构分析提供科学依据。     

Asteroid vesta: spectral reflectivity and compositional implications

The spectral reflectivity (0.30 to 1.10 microns) of several asteroids has been measured for the first time. The reflection spectrum for Vesta contains a strong absorption band centered near 0.9 micron and a weaker absorption feature between 0.5 and 0.6 micron. The reflectivity decreases strongly in the ultraviolet. The reflection spectrum for the asteroid Pallas and probably for Ceres does not contain the 0.9-micron band. Vesta shows the strongest and best-defined absorption bands yet seen in the reflection spectrum for the solid surface of an object in the solar system. The strong 0.9-micron band arises from electronic absorptions in ferrous iron on the M2 site of a magnesian pyroxene. Comparison with laboratory measurements on meteorites and Apollo 11 samples indicates that the surface of Vesta has a composition very similar to that of certain basaltic achondrites.     

乌鳢不同组织的LDH同工酶的研究

本文报道了应用聚丙烯酰胺凝胶垂直板电泳分离和研究成体乌直脏、骨骼肌、肾脏、１心肌、卵巢、脑、脾脏,眼和血清９种组织器官中ＬＤＨ同工酶。结果表明：除眼、脾组织中的ＬＤＨ分别为７条和５条同工酶带;肝脏、骨骼肌为１条和２条酶带外,多数组织中ＬＤＨ表现为４条酶带。进一步的分析表明,ＬＤＨ同工酶在活力和组织分布方面具有明显的特异性;血清,卵巢,骨骼肌的ＬＤＨ１,活力最强,而在其它组织中则ＬＤＨ４的活力最强。     

西北地区极端降水事件及环流特征分析

选取我国西北地区99个气象站1959～2008年的逐日降水资料,定义了不同台站的极端降水阈值,据此分析了极端降雨日数时空分布特征,并分析了极端降水日数偏多年、偏少年的环流特征。结果表明,空间上,西北地区极端降水阈值、极端降水日数和极端降雨量均是自北向南逐渐增大;时间上,极端降水日数和极端降雨量除西北东南部呈减少趋势,其他地区均表现为增加趋势,且存在明显的年际变化特征;在西北地区极端降水日数偏多年和偏少年,其环流特征存在明显的差异。     

Saturn's temperature field from high-resolution middle-infrared imaging

Saturn was imaged between 8 and 24.5 micrometers at approximately 3000-kilometer resolution with the Keck I Telescope. Saturn's atmosphere has zonal temperature bands, which are mostly uncorrelated with visible cloud reflectivity, strong 100-millibar zonal temperature oscillations near 32 degrees S, a warm south polar cap, and a compact hot point within 3 degrees of the south pole.     

Lunar spectral reflectivity (0.30 to 2.50 microns) and implications for remote mineralogical analysis

The spectral reflectivity (0.30 to 2.50 microns) of several lunar areas was measured with ground-based telescopes. A narrow absorption band centered at 0.95 micron was revealed for the first time. No other absorption bands appear in the spectrum. The reflectivity continues to rise at longer wavelengths throughout the spectral region studied. A comparison of the telescope measurements of an area 15 kilometers in diameter that includes Tranquillity Base with laboratory measurements of Apollo 11 soil samples reveals remarkable agreement, an indication that properties determined for fairly large lunar areas are relevant to local conditions. The spectra are interpretable in terms of surface mineralogy. The absorption band varies in both depth and shape and the overall slope of the curve changes with lunar area, an indication of differences in the composition and opacity of surface material. However, the lack of variety in the band position suggests there are no major differences (say, from mostly pyroxenes to mostly olivines) in the mineralogy at those sites studied.     

口虾蛄乳酸脱氢酶同工酶组织特异性的研究

以口虾蛄为材料进行研究,用聚丙烯酰胶凝胶电泳法,对其肌肉、心胜、腹鳃、肝胰腺及眼球5种组织器官进行乳酸脱氢酶(LDH)同工酶的研究分析。结果表明：不同组织中乳酸脱氢酶(LDH)的同工酶谱带存在差异,具有明显的组织特异性。肌肉、腹鳃、肝胰腺和心脏中有2条酶带,眼球中只有1条酶带,心脏中的谱带表达最浓,而腹鳃中的酶带表达最弱。     

Two-dimensional electronic excitations in self-assembled conjugated polymer nanocrystals

Several spectroscopic methods were applied to study the characteristic properties of the electronic excitations in thin films of regioregular and regiorandom polythiophene polymers. In the regioregular polymers, which form two-dimensional lamellar structures, increased interchain coupling strongly influences the traditional one-dimensional electronic properties of the polymer chains. The photogenerated charge excitations (polarons) show two-dimensional delocalization that results in a relatively small polaronic energy, multiple absorption bands in the gap where the lowest energy band becomes dominant, and associated infrared active vibrations with reverse absorption bands caused by electron-vibration interferences. The relatively weak absorption bands of the delocalized polaron in the visible and near-infrared spectral ranges may help to achieve laser action in nanocrystalline polymer devices using current injection.     

Spatial Variability of Turbulent Mixing in the Abyssal Ocean

Ocean microstructure data show that turbulent mixing in the deep Brazil Basin of the South Atlantic Ocean is weak at all depths above smooth abyssal plains and the South American Continental Rise. The diapycnal diffusivity there was estimated to be less than or approximately equal to 0.1 x 10(-4) meters squared per second. In contrast, mixing rates are large throughout the water column above the rough Mid-Atlantic Ridge, and the diffusivity deduced for the bottom-most 150 meters exceeds 5 x 10(-4) meters squared per second. Such patterns in vertical mixing imply that abyssal circulations have complex spatial structures that are linked to the underlying bathymetry.     

Seeding cumulus in Florida: new 1970 results

In the Florida single cloud experiments, the main result of the statistical analyses is that the dynamic seeding effect on rainfall is large, positive, and significant. From all the 1968 and 1970 data together, the seeding effect is estimated to be larger than a factor of 3; that is, the seeded clouds rained more than three times as much as the controls after the seeding run. On fair days, defined objectively by percentage of area covered by showers, the seeding effect is shown to be larger than the overall average, but it may be negative on rainy days. Rainy days in the tropics are about 10 percent of the days with rain, but they produce about half the total rainfall. The applicability of our single cloud results to other areas is not established but seems hopeful for many tropical and subtropical regions. It can be assessed by cloud population studies together with our numerical model (25). Guidance for the next steps toward practical rainfall enhancement and toward the understanding and modification of cloud systems in storms may be provided by our study of merger clouds. Mergers are shown often to produce more than an order of magnitude more rain than isolated clouds on the same day, probably owing to dynamic invigoration of the merged cloud circulations. Results of our first small attempt toward inducing and documenting mergers in a multiple cloud seeding experiment appear promising. Although far from statistically conclusive, they have opened a new frontier in the science and technology of dynamic cloud modification. It is also hoped that the multiple cumulus seeding experiments will help to clarify the formation of "cloud clusters" and their role in large-scale circulations, thus contributing to the focal subject of the Global Atmospheric Research Program in the tropics.     

伊犁绢蒿荒漠草地3种主要植物光谱及植被指数改进

【目的】伊犁绢蒿荒漠草地是新疆草地生态系统的重要组成部分,研究其主要植物地面光谱和植被指数特征是实现物种识别的基础,准确而实时获得群落物种组成变化、提高草地监测的质量和效果。【方法】借助SOC710 VP成像光谱仪,采集4月伊犁绢蒿荒漠草地群落高光谱影像,提取伊犁绢蒿(Seriphidium transiliense)、角果藜(Ceratocarpus arenarius)、叉毛蓬(Petrosimonia sibirica)和群落的原始光谱数据,通过反射率(REF)、吸收率(ABS)及其一阶微分(GREF和GABS)的变换提高光谱辨析度,分析并筛选敏感波段;通过各波段之间的相互组合计算NDVI值和DVI值,并以全波段计算的NDVI值和RVI值作为参考,筛选出优于全波段且差值最大植被指数。【结果】(1)3种主要植物光谱曲线相近,差异主要体现在光谱值的大小,在可见光400~780 nm和近红外波段780~820 nm的反射率均表现出角果藜>伊犁绢蒿>叉毛蓬>群落的特征;(2)通过反射率REF、吸收率ABS、一阶微分反射率GREF和一阶微分吸收率GABS的变换能够进一步扩大其光谱特征,相对稳定的波段有蓝光波段490~530 nm,绿光波段510~560 nm,红光波段620~760 nm,近红外波段780~820 nm。(3)GABS和ABS变换下490~530 nm和780~820 nm波段组合计算的NDVI’和RVI’在3种主要植物间的差异大于全波段和其它波段计算的NDVI’和RVI’。【结论】对敏感波段的反射率和吸收率进行一阶微分处理,并用于改进植被指数,能够提高伊犁绢蒿荒漠3种主要植物的识别效果。     

卫星遥感中国西北区东部近地面参数和植被参数分析

基于NOAA-16/AVHRR的资料结合定西和兰州的地面反射率观测资料,推算中国西北区东部地表特征参数和植被指数的最佳方案,用2001~2003年4~8月作物生长季5个地表特征的图像,按不同的土地覆盖类型分析地面反射率、表面温度、地气温差、植被指数（NDVI）、修正的土壤调整植被指数（MSAVI）和植被覆盖度的区域分布特征。结果表明,NDVI和MSAVI两者在不同的土地类型之间变化差别明显,尤其是在黄土高原与秦岭山地和青藏高原交界处的变化差别更明显。     

Band gap of forsterite

Optical absorption and reflectivity measurements on synthetic forsterite show that this silicate has a wide band gap of the order of 8.4 electron volts; thus it resembles other pure insulating oxides such as MgO. For natural olivines, in which divalent cations, mainly Fe(2+), can replace Mg(2+), all the optical absorption bands between the lattice overtones in the infrared and the first excitonic transition at 8.4 electron volts are due to the presence of iron.     

平原水库微污染水溶解氧含量模型反演与验证

对沧州大浪淀水库水体遥感影像进行处理得到水体反射率,分析水体反射率与实测溶解氧含量的相关性,构建了溶解氧含量与TM2＋TM3的多光谱模型,并对模型进行了反演和验证,结果与实际情况较吻合,说明所建立的模型可用于大浪淀水库水体溶解氧含量监测。     

基于TM遥感影像的南京市水体信息提取

以南京市TM遥感影像为例,利用HOT最优云监测变换方法对遥感影像进行薄云的去除,然后通过分析典型地物在不同波段的光谱特征,引入多波段组合（TM2＋TM3）/（TM4＋TM5）并辅以单波段（TM5）阈值的方法对南京市的水体信息进行了提取。     

滇中地区冰雹天气雷达反射率强度及高度特征分析

通过对近几年滇中地区发生冰雹灾害时雷达反射率的强度及对应高度数据进行统计分析,得到冰雹灾害发生时雷达反射率强度达到一定值时对应高度的区间分布情况。对利用天气雷达反射率产品预报短时对流天气过程,特别是冰雹灾害的预报有一定的参考价值。     

昆明裂腹鱼不同组织乳酸脱氢酶同工酶研究

采用不连续聚丙烯酰胺凝胶电泳法,对昆明裂腹鱼的眼球、心脏、肾脏、性腺、脾脏、肝胰脏、脑、鳃和肌肉等9种组织的乳酸脱氢酶同工酶(LDH)进行了测定。结果表明:昆明裂腹鱼LDH共有15条酶带表现出特异性,在不同组织中检出的LDH酶带数量不同,以肝胰脏中最多,共检出9条;在酶活性方面,LDH在脑、鳃、肌肉和肾脏等组织中活性最强,而在眼球组织中最弱。