天文/卫星组合点校捷联惯性导航系统算法研究

捷联式惯性导航系统通常采用卫星导航系统的位置、速度信息对惯导解算误差进行校正,但对于水下载体惯性导航系统而言,由于只能获得点位置信息,对惯导的校正精度以及校正参量有限。针对上述问题,提出了基于天文/卫星组合校正捷联式惯导技术,通过卫星精确定位信息和天文快速观测信息,全面修正惯导系统误差、提高导航精度。仿真结果表明,基于天文/卫星组合校正算法对惯导进行校正,相对于传统校正算法精度可提高约50%。     

电感耦合等离子体原子发射光谱法测定钒铁中8个杂质元素含量和方法精密度的验证

提出了电感耦合等离子体原子发射光谱法(ICP-AES)测定钒铁中硅、磷、铝、锰、镍、铬、铜、钛共8个杂质元素含量的方法。钒铁样品(0.5000g),先后加入50%(体积分数)硝酸溶液20mL及50%(体积分数)盐酸溶液10mL,在100℃左右加热溶解,溶解过程中应注意保持溶液体积在25mL左右。将溶液过滤并置于200mL容量瓶中作为母液留用。将滤纸及不溶物一并移入铂坩埚中,置于马弗炉中,先于250℃灰化20min,稍冷后加入无水碳酸钠和硼酸(质量比2∶1)组成的混合熔剂0.3g,升温至950℃融熔15min。冷却,用体积比1∶10的盐酸溶液10mL浸出熔块,将此溶液与上述母液合并并加水定容至200mL。此溶液供ICP-AES在仪器工作条件下进行分析。绘制校准曲线时,加入纯铁和五氧化二钒作为基体,以消除基体干扰,然后加入上述8种元素的标准溶液,并按上述溶液最终稀释体积条件和仪器工作条件制作曲线(R大于0.999)。为验证所提出的分析方法的测定数据的精密度,约请了10个实验室对8个不同含量水平的钒铁样品对方法作协同试验,按GB/T 6379.2-2004所规定的方法求算了重复性标准偏差Sr和重复性限r,以及再现性标准偏差SR和再现性限R,并求得所测定的8种元素在各自的测定范围内的r与w之间和R与w之间的函数关系,说明该方法有较好的稳定性和准确性,而且证明此方法是可行的。     

复合材料失效判据有效性验证方法研究

为系统地验证复合材料失效判据计算精度和有效性范围,给出了4种材料体系、6种铺层形式的层合板在单轴、双轴载荷下的失效试验数据,用以评估复合材料失效判据在单向层合板失效包线、多向层合板初始失效包线、多向层合板最终失效包线、层合板变形及层合板的破坏特性等五个方面的预测能力。并根据验证方法和有效性评估策略对失效判据计算精度进行量化考核,给出了失效判据在五个层面上的计算精度。     

某型机进近段高精度相对姿态实时测量技术

某型机在飞行训练过程中,进近段的二维相对姿态数据对于该型机安全着陆有着至关重要的作用。基于无线网络电台的双向数据传输系统能够实时获取进近段飞机相对理想着陆点的水平、垂直相对位置数据。通过上行链路上传着陆点的姿态数据,下行链路实时下传动动差分后的差分数据,最后在中心控制站进行二次数据处理。该技术获得的进近段二维相对姿态精度达到厘米级,满足飞行训练的需求。同时结合飞机显控数据以及视景图,以多角化动态关联的方式将实时获取的姿态数据等呈现给指挥员,更好地辅助指挥员进行着陆指挥工作。     

一种提高极值点处收敛精度的三阶WENO-Z格式

为了提高三阶WENO-Z格式在极值点处的计算精度,通过理论推导给出三阶WENO格式满足收敛精度的充分条件。采用泰勒级数展开的方式,推导给出所构造格式非线性权重的计算公式,并综合权衡计算精度和计算稳定性确定所构造格式的参数。通过两个典型的精度测试,验证了改进格式在光滑流场极值点区域逼近三阶精度。进一步选用激波与熵波相互作用和Richtmyer-Meshkov不稳定性等经典算例,证实了本文提出的改进格式WENO-PZ3相较其他格式（WENO-JS3和WENO-Z3）不仅具有较高的精度,而且降低了格式的耗散,提高了对流场结构的分辨率。     

多维气相色谱法提高丙烯腈色谱分析速度的方法

采用多维气相色谱法,既可提高丙烯醛、丙酮、乙腈、丙烯腈相邻两组分的分离度,又可提高分析速度。按GDX-502与402的体积比为85∶15比例混装长4.5m、内径3mm的色谱柱;氢气作为载气,流速为65mL/min;柱箱初温140℃保持15min,以15℃/min的速率升至180℃保持12min。丙烯腈样品中7种组分即可全部出峰,总分析时间为30min,比原国标推荐的方法缩短了近50min。     

Influence of Fe2O3 and V2O5 on Crystalline Structure of Mg-Al Spinel Synthesized by Waste Aluminum Slag

Mg-Al spinel is synthesized by using industrial waste-residue and basic magnesium carbonate in the aluminum factory as the main raw materials. The influence of V2O5 and Fe2O3 mineralizers on the structure, cell parameters and microscopic morphology of synthesized Mg-Al spinel has been discussed. The Mg-Al spinel is characterized by using XRD, SEM and relevant analytical software, such as Philips plus, Rietveld quantification and so on. The experimental results show that certain amounts of V2O5 and Fe2O3 are beneficial to the formation of Mg-Al spinel, and the optimum addition of V2O5 and Fe2O3 is respectively 2wt% and 3wt%. V2O5 has few effects on cell parameters of Mg-Al spinel; but Fe2O3 can form solid solution with Mg-Al spinel in which Mg-Fe spinel can also dissolve to form continuous solid solution. Therefore, with the increase of Fe2O3 content, the cell parameters of Mg-Al approximately present linear increase.     

Effects of Halogen Substitution on Naphthazarin Tautomerism in the Ground and Excited States

5,8-Hihydroxyl-1,4-naphthazarin was taken as a model compound to explore the effect of halogen substitution on intramolecular proton transfer process. Calculations indicate that the substitution in the R2- and R4-positions far away from the active region has much weaker influence on the IPT process than that in the R1-and R3-positions. IPT barriers for substitution in the R1-position are higher than that of parent molecule. However, it is quite reverse for substitution in the R3-position. The IPT process is a proton transfer process coupled with charge separation and coulombic interaction would be dominant during this process. As for naphthazarin, halogen substitution would decrease the quantum yields of O2 but increase those of 1O2.     

Studies on Monodispersed Microspheres of Zinc Sulfide Doped with Mn^2＋

In this paper,zinc acetate,manganese acetate and thiacetamide are used as raw materials to successfully synthesize monodispersed ZnS:Mn2+ microspheres by using hydrothermal method and taking P123 surfactant as a template. The products were characterized by XRD,STEM,FT-IR and N2 adsorption-desorption. And the results show that the diameter of this microsphere is 1.0 μm or so,which is larger than that of ZnS microsphere without Mn2+ doping,and it has monodispersion,smooth surface and uniform size. The doping of Mn2+ does not obviously change the structure of monodispersed ZnS microsphere. The photoluminescence peak lies in a wide band ranging from 450 to 650 nm,and the microspheres emit orange light; with the increase of Mn2+ concentration,fluorescence intensity of ZnS:Mn2+ microsphere changes,and when the mole ratio of Mn2+:Zn2+ is 0.3:1,the fluorescence intensity is the strongest.