大气湍流图像像素偏差机理分析

对大气湍流导致图像畸变和像素偏差的因素进行了深入分析,对大气湍流状态下激光发射远距离光束的光束漂移均方值进行仿真,分析光束漂移均方值曲线,为后续对图像畸变、像素偏差校正及克服湍流影响提供有效的理论依据。     

CuO/SnO2-In2O3 sensor for monitoring CO concentration in a reducing atmosphere

The CO sensing property of CuO-loaded SnO₂-In₂O₃ sensor was investigated in a reducing atmosphere. The sensor response to CO for CuO/SnO₂-In₂O₃ (8/2) was much higher than that for CuO/SnO₂ in the range of 200-1000 ppm of CO concentration. Such a high sensor response of CuO/SnO₂-In₂O₃ may originate from the high dispersion of CuO playing a role as sensing site.     

The CM-SAF operational scheme for the satellite based retrieval of solar surface irradiance — A LUT based eigenvector hybrid approach

The radiation budget at the earth surface is an essential climate variable for climate monitoring and analysis as well as for verification of climate model output and reanalysis data. Accurate solar surface irradiance data is a prerequisite for an accurate estimation of the radiation budget and for an efficient planning and operation of solar energy systems.This paper describes a new approach for the retrieval of the solar surface irradiance from satellite data. The method is based on radiative transfer modelling and enables the use of extended information about the atmospheric state. Accurate analysis of the interaction between the atmosphere, surface albedo, transmission and the top of atmosphere albedo has been the basis for the new method, characterised by a combination of parameterisations and “eigenvector” look-up tables. The method is characterised by a high computing performance combined with a high accuracy. The performed validation shows that the mean absolute deviation is of the same magnitude as the confidence level of the BSRN (Baseline Surface Radiation Measurement) ground based measurements and significant lower as the CM-SAF (Climate Monitoring Satellite Application Facility) target accuracy of 10 W/m². The mean absolute difference between monthly means of ground measurements and satellite based solar surface irradiance is 5 W/m² with a mean bias deviation of − 1 W/m² and a RMSD (Root Mean Square Deviation) of 5.4 W/m² for the investigated European sites. The results for the investigated African sites obtained by comparing instantaneous values are also encouraging. The mean absolute difference is with 2.8% even lower as for the European sites being 3.9%, but the mean bias deviation is with − 1.1% slightly higher as for the European sites, being 0.8%. Validation results over the ocean in the Mediterranean Sea using shipboard data complete the validation. The mean bias is − 3.6 W/m² and 2.3% respectively. The slightly higher mean bias deviation over ocean is at least partly resulting from inherent differences due to the movement of the ship (shadowing, allocation of satellite pixel). The validation results demonstrate that the high accuracy of the surface solar irradiance is given in different climate regions. The discussed method has also the potential to improve the treatment of radiation processes in climate and Numerical Weather Prediction (NWP) models, because of the high accuracy combined with a high computing speed.     

Characteristics of an electron source of a surface‐conduction electron‐emitter display

Abstract— The electron source is an essential part of a surface‐conduction electron‐emitter display (SED). An electron source for an SED was obtained after certain procedures were performed. By introducing a carbon atmosphere, the electron‐emission characteristics of a SED were studied experimentally. The electron‐emission characteristic curves were drawn after comparing the experimental data of the electron source obtained in a vacuum environment with the data obtained in a carbon atmosphere, from which it had proved that a carbon atmosphere could significantly improve the electron‐emission characteristics of a SED. As a result, both the device current and the emission current had become stronger and the efficiency of surface‐conduction electron emission had been improved significantly. The possible reasons were analyzed: more carbon, which could possibly form the electron‐emission region of a SED, was produced from the carbon atmosphere during the electrical activation process.     

军校营造良好学风的几点思考

针对当前军校学风建设存在的问题,从加强思想教育、完善教学管理制度、发挥队干部良好的导向作用、加强教风建设及落实教学管理制度等方面提出了军队院校营造良好学风的对策.     

溶胶—凝胶法制备掺钛SnO2薄膜的气敏光学特性研究

采用溶胶—凝胶(sol—gel)法制备掺钛SnO2薄膜,通过制备过程中变化不同质量分数的钛掺杂来制备3种不同质量分数(5%,10%,15%)的掺钛SnO2薄膜。在常温下对膜片在丙酮、甲烷气氛中进行气敏光学特性测试。结果表明:掺钛SnO2薄膜在常温下对不同的测试气体具有不同的反应,并且薄膜的灵敏度与掺杂量有关;质量分数为5%钛掺杂SnO2薄膜在丙酮气氛下的灵敏度在1300～2500 nm波长范围保持在13%左右,而质量分数为15%钛掺杂SnO2薄膜在甲烷气氛下的灵敏度在1700～2300 nm范围内保持在7%左右。     

Preservation of strawberries by modified atmosphere packages with other treatments

The impact of modified atmosphere packaging (MAP), in combination with ozone treatment and an edible film coating, on the preservation of strawberries was studied. A combination of 2.5% O₂ with 15% CO₂ was the optimum gas composition for the MAP of strawberries and prolonged shelf‐life by 4–6 days. When the strawberries were pre‐treated with a 4.3 mg/m³ ozone water dip and an edible coating prior to packaging, the shelf‐life was extended to 8–10 days. The results showed that two treatments [No.1: polyvinyl alcohol 134 (2%); monostearatacylglycerol (0.5%); phytic acid (0.05%); sorbitol (0.05%); sodium alginate (0.1%); absolute alcohol (8%): No.2: polyvinyl alcohol 134(1%); soluble starch (1%); glucose (1%); sucrose (1%); sodium alginate (0.1%); sorbitol (0.05%)] gave the best effects on strawberry quality and shelf‐life. All treatments (Nos 1–4) were obviously superior to check experiments for soluble sugar, ascorbic acid, acidity and anthocyanin. Furthermore, the treatments gave superior results for browning index, commodity ratio and permeability of the cell membrane. Copyright © 2006 John Wiley & Sons, Ltd.     

NiCr合金在含氯氧化性气氛中的高温腐蚀

研究了纯Ni以及不同Cr含量的NiCr合金在5%O2-0.3%HCl-N2(体积分数)气氛中800℃的腐蚀行为,结果表明:在氧化膜/基体金属界面处有氯化物生成,合金的加速腐蚀机制为氯参与的"活化腐蚀"过程.NiCr合金在腐蚀初期表现为失重与生成Cr的氯化物和氯氧化物的挥发性有关,但Cr依然有益于合金的抗氯化-氧化腐蚀性.     

氮基气氛的研究进展

简要回顾了国内外研究氮基气氛热处理的历史，概述了氮基气氛在热处理和烧结中的作用，介绍了氮基气氛的主要类型及应用，列举了氮基气氛的成分和供氮方式，着重评述了深冷法、变吸附法和膜分离三种制氮方法。     

A continuous/discrete simulation of controlled atmosphere (CA) cool storage systems: evaluation of plant performance/design and product quality evolution

In this paper, a controlled atmosphere storage model, developed earlier, is validated using an industrial CA cool storage facility with stepwise product loading strategy. The proposed combined continuous and discrete CA cool storage simulation model was able to represent the step response transients and continuous events, with accuracy less than the observed variability or at best with accuracy level as set by the measurement instrument. Moreover, the handling of discrete/continuous events enabled the implementation of practical operational procedures and to investigate their implication on plant performance/design and directly on the product quality. The model is a valid working model for design and optimization of CA cool storage facilities both with respect to plant performance and final quality of the stored product.