小型无人直升机的纵向横向解耦优化控制

论文根据小型无人直升机的机理建立了数学模型,并在悬停状态下近似线性化,运用Matlab的非线性控制工具箱(NCD)设计了具有很强鲁棒性的控制器,实现了对于小型无人直升机的纵向和横向的解耦控制,仿真结果证明了方法的有效性。     

电弧作用下 AgMeO 触头材料的物理冶金过程分析

本文分析了ＡｇＭｅＯ触头材料电弧侵蚀机理,对电弧的热力作用下触头材料的各种响应从物理冶金本质角度进行全面研究,在此基础上对ＡｇＭｅＯ触头材料组元和组织的优化设计作了完整的分析讨论,提出优化设计判据,最后提出能充分表征触头材料电气使用性能的材料物理性能参数。     

带屏蔽的多平行微带线分析公式及其应用

本文利用带状线的电容分布特点给出了带屏蔽的多平行耦合微带线的分布电容模拟分析公式,并采用Weeks给出的超松弛差分数值计算方法进行了验算,误差不超过2％。最后,给出了本公式的两个应用实例,实验结果表明,效果令人满意。     

Effect of feed array configuration on the Field-of-View of radio telescope antenna

Phased Array Feed (PAF) is a small two-dimensional phased array antenna, playing a role as the multi-beam feed for the reflector antenna. The prominent capability of large continuous Field-of-View (FoV) coverage and fast survey speed makes PAF the promising feed for radio telescopes. In this paper, the effect of feed array of PAF on the gain fluctuations over FoV is analyzed on a simplified model of the Five-hundred-meter Spherical Aperture radio Telescope (FAST), including illumination pattern edge taper, element spacing, element arrangement and element amount. And the differences between rectangular and hexagonal array arrangements are compared. The relationship between the FoV and array configuration are concluded at last.     

Multifunctional picoliter droplet manipulation platform and its application in single cell analysis

We developed an automated and multifunctional microfluidic platform based on DropLab to perform flexible generation and complex manipulations of picoliter-scale droplets. Multiple manipulations including precise droplet generation, sequential reagent merging, and multistep solid-phase extraction for picoliter-scale droplets could be achieved in the present platform. The system precision in generating picoliter-scale droplets was significantly improved by minimizing the thermo-induced fluctuation of flow rate. A novel droplet fusion technique based on the difference of droplet interfacial tensions was developed without the need of special microchannel networks or external devices. It enabled sequential addition of reagents to droplets on demand for multistep reactions. We also developed an effective picoliter-scale droplet splitting technique with magnetic actuation. The difficulty in phase separation of magnetic beads from picoliter-scale droplets due to the high interfacial tension was overcome using ferromagnetic particles to carry the magnetic beads to pass through the phase interface. With this technique, multistep solid-phase extraction was achieved among picoliter-scale droplets. The present platform had the ability to perform complex multistep manipulations to picoliter-scale droplets, which is particularly required for single cell analysis. Its utility and potentials in single cell analysis were preliminarily demonstrated in achieving high-efficiency single-cell encapsulation, enzyme activity assay at the single cell level, and especially, single cell DNA purification based on solid-phase extraction.     

基于服务蓝图的网上零售业感知服务质量

通过绘制网上零售业的服务蓝图和相关的企业调研识别了所涉及到的服务接触点,以此为基础概括出网上零售业中的服务接触因素,并运用模糊综合评价方法对网上零售业的顾客感知服务质量进行测评,分析网上零售业中的失败服务接触点,目的在于通过改进失败的服务接触点,提高网上零售业的顾客体验。通过测评,顾客对网上零售业的物流配送和在线服务感知一般。     

Enhanced Reversible Zinc Ion Intercalation in Deficient Ammonium Vanadate for High-Performance Aqueous Zinc-Ion Battery

Ammonium vanadate with bronze structure (NH4V4O10) is a promising cathode material for zinc-ion batteries due to its high specific capacity and low cost. Howeve...     

核电厂设备闸门外压极限承载特性研究

采用有限元分析方法对设备闸门外压极限承载特性进行研究。在ANSYS程序中建立参数化计算模型,通过非线性屈曲分析得到设备闸门封头的外压极限载荷。计算结果与经验公式结果相近,验证了有限元分析方法的可靠有效性。对影响外压极限承载特性的设计参数进行了敏感性研究,总结出其影响变化规律。优化设计示例表明该研究方法具有实用性,可为设备闸门的结构设计提供优化方案。     

火花点火式天然气发动机燃烧系统的研究

本介绍了天然气发动机预燃室燃烧系统的研制过程，新设计的燃烧系统工作可靠、性能优良。试验结果表明：预燃室内混合气着火稳定、火焰传播迅速；主燃室燃烧速度高、持续期短、无后燃现象，整机性能比原机有较大的提高。     

除草剂吡嘧磺隆的合成方法

总结了除草剂吡嘧磺隆合成方法,并从反应步骤、总产率、反应条件和原料等方面对合成方法进行了比较和分析。寻找到经济合理,高效环保,适合工业化大生产的生产方法。