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.     

某型榴弹炮海上运输及存放中炮膛的防护处理

对4种炮膛防护工艺进行了中性盐雾试验以及大气暴露试验，通过试验对比得到了优选品种，说明了推荐原因。     

Preparation and characterization of SiC fibers with diverse electrical resistivity through pyrolysis under reactive atmospheres

Due to their fantastic mechanical and high-temperature resistant properties, SiC fibers with electrical resistivity of different orders of magnitude are of great interest for the fabrication of advanced composites with electromagnetic wave absorbent performance as both structural and functional materials. On the basis of well-developed route to prepare SiC fibers, in this work, we demonstrated a facile strategy to fabricate SiC fibers with electrical resistivity of 10⁻¹–10⁶ Ω cm by simply employing hydrogen and ammonia as the reactive atmospheres. The SiC fibers with different electrical resistivity had favorable morphologies, with uniform elemental distribution and stable C/Si ratio towards the fiber interior. Moreover, these fibers exhibited excellent mechanical strength and high temperature performance. Due to the innovative strategy, convenient operation and scalable preparation, the method in this work can be further extended to prepare SiC base fibers with adjustable electrical resistivity from other precursors.     

Approaches adopted to assess environmental impacts of PCDD/F emissions from a municipal solid waste incinerator

Different approaches were carried out in this work to assess environmental impacts of a municipal solid waste incinerator. A total of seven sites in the vicinity of the facility were chosen to collect air, banyan leaf and soil samples for analyses of PCDD/Fs by high-resolution gas chromatography/high-resolution mass spectrometry. Based on the PCDD/F concentrations of the three matrices determined at sites upwind, downwind and area of maximum ground concentration, it was found that the environmental impact of the MSWI was not obvious. PCDD/F concentration isopleths of the three environmental compartments coupled with wind rose of the region proved that the influence of the MSWI on the environment was also rather limited. It clarified emission sources by confirming that the PCDD/F concentrations originated mostly from the existing stationary emission sources in the vicinity. Through principal component and cluster analyses on congener profiles, the influence of metallurgical facilities and medical waste incinerators on the ambient air was assessed. Moreover, the modeling of ISCST3 demonstrated also that the contribution of the MSWI to ambient atmospheric PCDD/Fs was minimal. The approaches studied have led to identical conclusions, and thus are useful to cross-evaluate the environmental impact of an MSWI.