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1.
空间斜程能见度的影响因素分析   总被引:12,自引:4,他引:8       下载免费PDF全文
 空间斜程能见度是空间目标识别的重要参量。水平能见度与大气消光参数有明确的关系,而斜程能见度与大气消光参数、观测方向、太阳天顶角等多种因素有关,目前尚未有明确的结果。从辐射传输理论出发,通过δ-Eddington近似求解辐射传输方程,尝试推导了空间斜程能见度的表达式,探讨了斜程能见度与观察者视角、太阳高度角以及大气光学特性之间的关系。  相似文献   
2.
Research on Chemical Intermediates - Antibiotic-resistant penicillin binding protein (PBPs) production is one of the reasons why bacteria develop resistance to β-lactam antibiotics, and this...  相似文献   
3.
 提出了一种大气光学折射率结构常数的数值模式。通过敏感性分析发现,对折射率结构常数有显著影响的参数是:一年中的不同日期、土壤的热容量和含水量、雪地和水面上、云量等,风速大小几乎对折射率结构常数没有什么影响。  相似文献   
4.
An eco‐friendly coating system, which is largely biobased, has been developed from castor and cottonseed oil. Cottonseed oil was functionalized with maleic anhydride by “ene” reaction to give maleinized cottonseed oil (MACSO); the anhydride groups were reacted with isocyanates to yield –NCO terminated polyurethane prepolymer. The prepolymer was further chain extended with hydroxyl groups of castor oil to give polyurethane‐imides (PUIs). The cross‐linked films thus obtained had good mechanical properties, and the imide groups in the backbone improved the corrosion resistance of PUIs as revealed by potentiodynamic polarization study. With increasing content of MACSO, thermal stability, glass transition temperatures (Tg), tensile strength, and corrosion resistance of resulting PUIs significantly increased.  相似文献   
5.
Russian Journal of Organic Chemistry - A new series of fused tricyclic coumarin derivatives were designed, synthesized by a simple and convenient method, starting from 4-hydroxycoumarin and...  相似文献   
6.
Resonance Raman spectra of oxygenated and deoxygenated functional erythrocytes are calculated by using Lie algebraic technique at 785 nm. The results are obtained by this method is accuracy with the experimental data. So, the algebraic techniques are appropriate to the Raman spectra of red blood cells.  相似文献   
7.
Synthesis of 1-aryltetralins is described by the Fridel-Crafts arylation of 1-tetrols with phenol.  相似文献   
8.
 提出了一种大气光学折射率结构常数的数值模式。一次输入日期、时间、经纬度、温度、湿度、风速、粗糙度、土壤参数,云量等相关参数,可得到24h内的温度、湿度、风场、折射率结构常数等量。通过与实测对比表明,无论是月平均折射率结构常数还是某天的折射率结构常数,模式计算与实测数据都符合得很好。模式计算的向下总辐射通量与实测数据基本一致。  相似文献   
9.
We describe an electrochemiluminescence (ECL) immunoarray incorporated into a prototype microfluidic device for highly sensitive protein detection and apply this system to accurate, sensitive measurements of prostate-specific antigen (PSA) and interleukin-6 (IL-6) in serum. The microfluidic system employed three molded polydimethylsiloxane (PDMS) channels on a conductive pyrolytic graphite chip (2.5?×?2.5 cm) inserted into a machined chamber and interfaced with a pump, switching valve, and sample injector. Each of the three PDMS channels encompasses three 3 μL analytical wells. Capture-antibody-decorated single-wall carbon nanotube forests are fabricated in the bottom of the wells. The antigen is captured by these antibodies on the well bottoms. Then, a RuBPY-silica-secondary antibody (Ab2) label is injected to bind to antigen on the array, followed by injection of sacrificial reductant tripropylamine (TPrA) to produce ECL. For detection, the chip is placed into an open-top ECL measuring cell, and the channels are in contact with electrolyte in the chamber. Potential applied at 0.95 V versus Ag/AgCl oxidizes TPrA to produce ECL by redox cycling the RuBPY species in the particles, and ECL light is measured by a charge-coupled device camera. This approach achieved ultralow detection limits of 100 fg?mL?1 for PSA (9 zeptomole) and 10 fg?mL?1 (1 zeptomole) for IL-6 in calf serum, a 10–25-fold improvement of a similar non-microfluidic array. PSA and IL-6 in synthetic cancer patient serum samples were detected in 1.1 h and results correlated well with single-protein enzyme-linked immunosorbent assays.  相似文献   
10.
The structures of six new lignans isolated from the heartwood of Gmelina arborea have been determined. They are 6“ - bromo - isoarboreol, 4 - hydroxysesamin, 4,8 - dihydroxysesamin, 1,4 - dihydroxysesamin (gummadiol), 2 - piperonyl - 3 - hydroxymethyl - 4 - (α - hydroxy - 3,4 - methylenedioxybenzyl) - 4 - hydroxytetrahydrofuran, and the 4 - O - glucoside of 4 - epigummadiol. The 1H and 13C NMR and mass spectra of these compounds and their derivatives are discussed, and the structure previously assigned to a germination inhibitor from Aegilops ovata is questioned.  相似文献   
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