新型耐紫外光防腐涂料的开发研制

针对塔里木沙漠自然环境的特殊防护需求，研制出适合沙漠油气田工程使用的新型耐紫外光、耐风蚀涂料，并在塔里木油田进行了中试应用，表明该涂料完全能够满足沙漠油气田地面构筑物的外防腐需要。     

Comparison of the NIST and NPL Air Kerma Standards Used for X-Ray Measurements Between 10 kV and 80 kV

A direct comparison was made between the air kerma primary standards used for the measurements of low-energy x rays at the National Institute of Standards and Technology (NIST) and the National Physical Laboratory (NPL). The comparison was conducted at the NPL using NPL reference radiation qualities between 10 kV and 80 kV. The results show the primary air-kerma standards to agree within 0.6 % of their values for beam qualities up to 80 kV.     

海上稠油油田合理单井产能预测新方法

海上稠油油田开发具有特殊性,使得常规产能评价方法的应用受到限制。目前海上油田产能评价采用基于DST测试资料的比采油指数法,由于校正系数是经验值,取值具有人为性,往往导致产能评价结果过高或过低。通过分析层间干扰、DST测试时间及地层伤害等因素对产能的影响,提出了海上稠油油田合理单井产能预测的新方法,该方法将经验校正系数分解为3个分校正系数,即层间干扰校正系数、DST测试时间校正系数和地层伤害校正系数,并给出了各自的确定方法。实例应用表明,采用该方法能够得到较传统的比采油指数法更加客观的产能评价结果。     

Energetics of charged point defects in rutile TiO2 by density functional theory

The defect formation energies of all possible charge states of point defects in TiO₂, including titanium interstitials, titanium vacancies and oxygen vacancies, are calculated in the phase space of temperature, oxygen partial pressure and Fermi level by combining density functional theory (DFT) and thermodynamic calculations. The point defect phase diagram illustrates that fully charged defects dominate in most regimes. The calculations not only give reasonable defect formation energies compared with prior experimental measurements, but also predict n-type TiO₂ at high T and low P_O2, and p-type TiO₂ at low T and high P_O2, which agrees well with experimental data. In addition, we evaluate methods for correcting the effects of artificial electrostatic interactions caused by periodic boundary conditions in the DFT calculations, including the electrostatic potential alignment correction (ΔV correction) and the Makov–Payne correction.     

电力系统电磁/机电暂态实时混合仿真的关键技术

电力系统的巨大发展给仿真技术带来新的挑战，传统的仿真手段已不能满足实际大规模互联系统分析的要求。专家、学者结合电磁、机电暂态仿真的优点提出了混合仿真的技术路线。文中综述了国内外混合仿真技术的研究、发展情况，明确了混合仿真的2个基本要求以及现阶段面临的实质难题，包括分网方案制定、单侧计算时边界条件和对侧等值、故障时刻交互时序等;提出了预测校正的思路，阐明了其可行性，展望了混合仿真技术的发展方向。     

基于Bayes方法的航空子母炸弹制导精度分析

针对风修正系列航空子母炸弹的制导精度鉴定问题，根据炸弹的试验投放情况和毁伤机理，讨论了毁伤效能战术指标与制导精度指标之间的关系。在小子样条件下，运用Bayes理论方法，提出了航空子母炸弹的制导精度和布撒均匀度鉴定方案，研究了对Bayes SPRT序贯方法的改进。仿真结果表明：所提出的方案可以减少所需的试验样本量，可以用于小子样条件下航空子母炸弹的精度鉴定问题。     

基于脉冲控制的末段弾道修正弹点火相位优化研究

基于传统脉冲发动机点火控制逻辑，从理论上分析了点火相位特性和剩余误差，发现当脉冲发动机数量不足时，存在着较大的剩余误差。提出了一种在脉冲发动机数量不足条件下，以修正后剩余弹道偏差所需脉冲发动机数量最小为目标的点火相位控制优化策略，并采用6自由度弹道仿真验证了方法的有效性。     

A polysilazane coating protecting polyimide from atomic oxygen and vacuum ultraviolet radiation erosion

A polysilazane coating was prepared on polyimide substrate by the polymeric precursor method to protect space materials from attack of atomic oxygen (AO) and vacuum ultraviolet radiation (VUV) in low earth orbit (LEO) environment. Erosion kinetics, surface morphologies, and surface composition investigation indicate that this polysilazane coating possesses excellent AO resistance, and displays low shrinkage tendency in AO exposure. The erosion yield of the prepared polysilazane coating is 3.5 × and 2.1 × 10^− 26 cm³/atom during AO exposure and simultaneous AO and VUV exposure, respectively. The low AO erosion yield of the polysilazane coating results from the formation of a SiO₂-rich layer on its top surface during exposure, and the VUV radiation is able to create free radical sites on the exposed surface, promoting the formation of a uniform SiO₂-rich surface layer.     

Thermoelastic investigation of an aluminium helicopter component under non-adiabatic conditions

Thermoelastic Stress Analysis (TSA) has been used to analyze an aeronautic cross-shaped structural component, composed of several riveted parts, made of different aluminium alloys. Due to the high thermal diffusivity of aluminium, some parts of the component were not in adiabatic conditions during the test, causing an attenuation of the temperature peaks, linked to the stress distribution. Furthermore, the presence of a thick primer coating altered the TSA results on the component especially at high frequencies. After the removal of the primer from some parts of the surface, a correction procedure was applied to compensate for the heat diffusion, thus obtaining quantitative results, which proved to be in very good agreement with the stress values obtained by strain gauges.     

Climate change and viticulture: A European perspective on climatology, carbon dioxide and UV-B effects

Predicted changes in the climate of European viticultural regions over coming decades may alter significantly both the spectrum and the distribution of grape varieties currently used. Changes observed over recent years confirm those predictions. In particular, shifts in precipitation patterns will affect most European regions, with increased risk of drought, and given this scenario, the consequences would be most dramatic for the Iberian peninsula. Soil practices may have to be adapted to account for changes in soil moisture and decay rates of organic matter. Rising CO₂ concentration alone may increase grape production and water use efficiency, but more comprehensive studies predict decreases in yield when increasing temperature and changes in solar radiation are considered simultaneously. As part of those changes in solar radiation, levels of UV-B radiation will probably continue to rise, and will have a direct impact on grape composition and thus flavour development via alteration of secondary metabolites such as flavonoids, amino acids and carotenoids.