滑翔增程弹方案弹道特性的研究

阐述了滑翔增程弹的飞行原理，建立了滑翔增程弹的方案弹道模型，通过数值计算得到了滑翔增程弹方案弹道的形状特征、弹丸飞行速度沿全弹道的变化规律和最大射程角的特点，对今后进行滑翔增程弹的设计有重要促进作用。     

Conversion of coalbed methane surrogate into hydrogen and graphene sheets using rotating gliding arc plasma

The use of atmospheric rotating gliding arc(RGA) plasma is proposed as a facile, scalable and catalyst-free approach to synthesizing hydrogen(H_2) and graphene sheets from coalbed methane(CBM). CH_4 is used as a CBM surrogate. Based on a previous investigation of discharge properties, product distribution and energy efficiency, the operating parameters such as CH_4 concentration, applied voltage and gas flow rate can effectively affect the CH_4 conversion rate,the selectivity of H_2 and the properties of solid generated carbon. Nevertheless, the basic properties of RGA plasma and its role in CH_4 conversion are scarcely mentioned. In the present work, a 3D RGA model, with a detailed nonequilibrium CH_4/Ar plasma chemistry, is developed to validate the previous experiments on CBM conversion, aiming in particular at the distribution of H_2 and other gas products. Our results demonstrate that the dynamics of RGA is derived from the joint effects of electron convection, electron migration and electron diffusion, and is prominently determined by the variation of the gas flow rate and applied voltage. Subsequently,a combined experimental and chemical kinetical simulation is performed to analyze the selectivity of gas products in an RGA reaction, taking into consideration the formation and loss pathways of crucial targeted substances(such as CH_4, C_2H_2, H_2 and H radicals) and corresponding contribution rates. Additionally, the effects of operating conditions on the properties of solid products are investigated by scanning electron microscopy(SEM) and Raman spectroscopy. The results show that increasing the applied voltage and decreasing CH_4 concentration will change the solid carbon from its initial spherical structure into folded multilayer graphene sheets, while the size of the graphene sheets is slightly affected by the change in gas flow rate.     

Atmospheric pressure gliding arc discharge plasma treatments for improving germination,growth and yield of wheat

Wheat (Triticum aestivum) seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6min treatment was provided 95%–100% germination rate. For the treatment duration of 3 and 9 min the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were improved. The grain yield of wheat was increased ∼20% by 6min treatment with H ₂ O/O ₂ plasma with respect to control.     

OH and O radicals production in atmospheric pressure air/Ar/H2O gliding arc discharge plasma jet

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic(OES) diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx?≈?5550–9000 K, rotational Tr?≈?1350–2700 K and gas Tg?≈?850–1600 K temperatures, and electron density n?(1.1-1.9) ′101 4 cm~(-3) e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n e.The productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.     

滑翔增程弹稳定储备量的优化设计与仿真

稳定储备量是保证弹丸稳定飞行的前提.本文结合某滑翔增程弹的结构参数和数学模型,对有控滑翔增程弹的稳定储备量进行了优化仿真.通过仿真验证,得出了有控滑翔增程弹稳定储备量的最佳设计范围,对于气动力设计、控制系统的设计及总体结构设计具有重要价值.     

大气滑动弧放电对沙门氏菌的灭活机制及在鸡蛋保鲜中的应用

为了保持鸡蛋的新鲜度、延长其保质期,本研究提出了一种可在室温和大气环境中进行灭菌处理的新型冷杀菌技术,即滑动弧放电技术。首先,将配制好的沙门氏菌液均匀接种在鸡蛋表面,然后使鸡蛋以一定的自旋速率通过等离子体放电区域进行灭菌处理,从鸡蛋表面取得菌样后进行灭活机制研究,并将灭菌处理后的鸡蛋在37℃条件下进行贮藏,通过测定质量损失率和哈夫单位来评价大气放电技术对鸡蛋品质的影响。扫描电子显微镜观察和细胞外蛋白质质量浓度检测结果表明,大气滑动弧放电技术可对沙门氏菌产生有效的刻蚀作用,导致细胞膜破碎和胞内蛋白质泄漏。同时,鸡蛋品质检测表明,滑动弧放电处理组无论作用时间长短,鸡蛋质量损失率增大的程度均比对照组明显,但哈夫单位的降低程度小于对照组,说明大气滑动弧放电可在一定程度保持鸡蛋的新鲜度。     

Decontamination of infected plant seeds utilizing atmospheric gliding arc discharge plasma treatment

In agriculture production,plant health is threatened by pathogens parasitic on seeds;hence,it is necessary to disinfect harvested seeds before germination.In this study,a technique of gliding arc plasma treatment was proposed and investigated.The experiment was conducted to treat Astragalus membranaceus (A.membranaceus) seeds that were artificially infected with Fusarium oxysporum (F.oxysporum).The plasma treatment duration varied from 30 s to 270 s.Direct and indirect treatments were compared to evaluate the inactivation efficiency of the F.oxysporum spores on the surface of seeds.The results indicated that the direct treatment behaved significantly better in disinfection than the indirect way.Meanwhile,experiments of the quantitative assessment of seed germination were also conducted,including the germination rate,the germination potential,and the germination index.The results showed that the inactivation efficiency increased as the plasma treatment time was extended.When the treatment time was 90 s,the inactivation efficiency reached more than 98％.The plasma treatment of 270 s had a complete devitalization of F.oxysporum spores on the surface of the seeds.After the treatment of 30 s and 90 s,the seed germination parameters improved significantly.This study verified the inactivation efficacy of gliding arc discharge plasma under atmospheric pressure.The technique of gliding arc treatment shows advantages of energy saving and adaptation and has the potential to be utilized in industry.     

大机组通流间隙变化的研究

该文着重介绍了用实测高温管道位移并结合理论计算的办法来求出管道对汽缸的作用力的方法 ,而且在实际机组上应用成功。该方法相对于采用高温应变实测管道作用力的办法简易可行 ,易于实施。此外该文还对电站中较多发生的汽缸膨胀不畅故障作了分析研究。图 2表 1     

基于C/S体系结构的视频传输系统的实现方法

论述了基于C/S体系结构的视频传输系统的实现,提出了一种数据报方式下采用自定义滑动窗口协议实现视频的可靠传输。有效地解决了视频的动态传输。     

连续滑动窗的递推-Pruning-FFT算法

在信号谱线分析中,经常用到滑动窗的FFT计算,由于传统的FFT在N值较大和滑动步距较小时,计算量较大,在"实时"通信系统中难以实现,本文提出一种连续滑动窗的递推 PruningFFT算法,该算法充分利用了前窗的计算结果并将输入序列转换为一个输入端仅有少数非零点的特殊序列,不仅降低了计算量,而且提高了使用的灵活性和实时性。