Experimental testing of correlations to calculate the atmospheric “transparency window” emissivity coefficient

An experimental verification of the correlations existing in literature for the calculation of the coefficient of emissivity inside the atmospheric transparency window, situated in the wavelength band 8–14 μm, has been performed. In addition, the authors propose a new correlation for the calculation of the coefficient ε_in, easily applicable since it presupposes the knowledge of the global emissivity of the sky, for which there are a lot of correlations in literature.     

The method Heliosat-2 for deriving shortwave solar radiation from satellite images

This article presents the method Heliosat-2 that converts observations made by geostationary meteorological satellites into estimates of the global irradiation at ground level. This new version integrates the knowledge gained by various exploitations of the original method Heliosat and its varieties in a coherent and thorough way. It is based upon the same physical principles but the inputs to the method are calibrated radiances, instead of the digital counts output from the sensor. This change opens the possibilities of using known models of the physical processes in atmospheric optics, thus removing the need for empirically defined parameters and of pyranometric measurements to tune them. The ESRA models are used for modeling the clear-sky irradiation. The assessment of the ground albedo and the cloud albedo is based upon explicit formulations of the path radiance and the transmittance of the atmosphere. The method Heliosat-2 is applied to Meteosat images of Europe for the months of January 1995, April 1995 and July 1994. Pyranometric measurements performed by thirty-five meteorological stations are used to assess the performances that are close to those of Heliosat-1 found in the literature. Possible improvements are discussed.     

我国大气环境PM2.5来源、分布、危害现状分析

从人体健康和环境影响两个方面分析了大气污染物PM10和PM2.5带来的危害。列举了我国部分大城市的PM2.5的检测数据、分析其污染源及环境的影响;通过对我国整体PM2.5的分析,指出各主要污染源所占的比重及存在的问题,为空气环境的治理提供参考。     

Compensation Method of Laser Drifting by Atmosphere Turbulence in Large Shafting Aligning

Instead of the rotor shafting line, visible laser beam, as a centering and adjusting benchmark of rotor bearing groove or static components, has been used to examine and repair the high precision shafting in many industry areas. Atmosphere turbulence is one of the important factors that affect shafting alignment precision. A correcting method is proposed in this paper, which monitors the light target to measure the drift of laser direetrix in real time and compensates the error using beeline correction.     

气调包装中的配气技术

介绍食品气调小包装中，简易的配气装置、原理和方法。     

激光在大气传输中的损耗和折射

激光束在大气中的损耗和折射是激光大气通信等实验研究的重要课题,以射线理论和数值计算为基础,给出了激光束在大气传输中的损耗和折射的求解方法,得出了相关的数学表达式,同时对不同的方法作了简单的比较。     

氧化焰烧成高强度电瓷材料的研究

用正交实验法，通过调整配方、改变工艺条件，在氧化气氛下烧制了高强度电瓷产品。同时用XRD、SEM等测试技术对瓷胎的显微结构进行了分析。结果表明：用氧化气氛烧制高强度电瓷是切实可行的，产品的机械强度达到了140MPa。     

大气相位屏的协方差冲激函数产生法

提出正交基为冲激函数的协方差法,在Matlab中仿真实现符合大气湍流统计分布(vonKarman谱和Kolmogorov谱)的大气相位屏。协方差冲激函数产生法对连续波前相位进行冲激函数正交分解,根据正交分解系数的协方差模拟平行光通过大气后的瞬时波前相位。计算多帧相位屏的波前结构函数,与理论值比对,验证产生大气相位屏的正确性。根据比对结果得,该方法产生的相位屏精度高,对于Kolmogorov谱,该方法产生的大气相位屏的波前结构函数误差约为理论波前结构函数均值的1%。     

The effect of modified atmosphere packaging on the quality of Honeoye and Korona strawberries

Strawberries (cultivars Honeoye and Korona) were stored in perforated polypropylene bags at 5 °C for 10 days. Unpackaged strawberries were used as a reference. Several quality parameters were monitored during the storage period. The packaged strawberries retained their weight throughout the experiment as opposed to the unpackaged samples which lost 1.5% of their weight per day because of dehydration. The aroma profile of Honeoye strawberries was not affected by storage in modified atmospheres. In Korona fruits, on the other hand, there was a considerable increase in ethyl acetate levels, indicating unwanted metabolism caused by the altered gas composition. The production of potential off-odours was, however, not possible to distinguish in the sensory analyses of the strawberries. The results indicated that storage in a modified atmosphere (11–14% O₂ and 9–12% CO₂) can be used to maintain the quality of Honeoye and Korona strawberries for a longer time, than if kept in air in open containers.     

Effect of atmosphere control on magnetic properties of CaO-Al2O3-SiO2-Fe3O4 glass ceramics

The influences of atmosphere during processes of melting and heat treatment, heat treatment temperature, Fe₃O₄ content and basicity on the magnetic properties of magnetite-based glass ceramics were investigated. For sample containing 20 % Fe₃O₄ melted in different atmospheres, the highest saturation magnetisation was realized in 20vol% air + 80 vol% Ar, due to the fact that ratio of Fe³⁺ to Fe²⁺ in melt obtained in this atmosphere was close to 2. However, it was found that the coercivity of glass ceramics was not affected by the melting atmosphere. A high sintering temperature led to the decrease of saturation magnetisation and the increase of coercivity. As increasing Fe₃O₄ content, the main crystal phase transformed from CaSiO₃ to CaFe_0.6Al_1.3Si_1.08O₆ and finally to magnetite phase, accompanied by the increase of saturation magnetisation and coercivity. In addition, the increase of basicity caused the decrease of saturation magnetisation and the increase of coercivity.