23 research outputs found

    Synthesis and structural analysis of 2-mercaptonicotinic acid oxovanadium(Ⅴ)

    Get PDF
    目的合成新型有机羧酸氧钒配合物——2-巯基烟酸氧钒(V)配合物。方法以V2O5、2-巯基烟酸等为原料,采用水热法制备,以热重分析法、红外光谱、紫外光谱、原子吸收光谱和质谱对其结构进行初步确证。结果合成产物为淡黄色结晶,其红外光谱图上有3 093--2 879、1 566、1 683、1 446、881 CM-1等多处特征吸收峰,紫外吸收光谱在350 nM出现强的π→πx吸收,配合物元素分析数据、结构参数与计算值相符合。结论所合成的配合物为目标配合物。Objective To synthesize and identify 2-mercaptonicotinic acid oxovanadium(Ⅴ) complex.Methods 2-mercaptonicotinic acid oxovanadium(Ⅴ) complex were synthesized with the hydrothermal method.Its chemical structure was determined by thermogravimetric analysis,IR,UV and atomic absorption spectra.Results Pale yellow crystals of 2-mercaptonicotinic acid oxovanadium(Ⅴ) complex were obtained with characteristic absorption peaks at 3 093-2 879、1 566、1 683、1 446、881 cm-1 in IR,and along with strong π→π× absorption at 350 nm in UV.The complex′s elemental analysis and structural data were identical with calculated results.The crystals had special morphometry through preliminary study,and its diagrammatic sketch of crystal structure was simulated.Conclusions 2-mercaptonicotinic acid oxovanadium(Ⅴ) complex were synthesized successfully

    Acceleration Feedback Enhanced Controller forWind Disturbance Rejection of Rotor Unmanned Aerial Vehicle

    No full text
    为了提高无人机的风扰抑制能力,实现无人机安全飞行和精准控制,提出了一种基于加速度反馈的旋翼无人机抗风扰方法.该方法不需要改变原有的控制器结构,在原有的控制器基础上引入角加速度和线加速度反馈,从而实现更快速且更高精度的角度和位置跟踪,提升系统的扰动抑制能力.同时,为了将该算法部署在实际的无人机平台上,提出了一种简单、快速以及适用于加速度反馈的无人机参数辨识方法.结合该方法,将加速度反馈应用到一个六旋翼机上,并在户外持续风和阵风扰动环境下进行了实验验证.实验结果表明,加速度反馈增强型控制器可以有效地抑制这两种风扰,极大地提高了风扰条件下的无人机控制精度.</p

    激光辐射烧结法制备铁/铜梯度复合材料

    No full text

    One man's watering hole

    No full text
    Mr Alade from the Animal Science Department of the University of Maiduguri in Nigeria wants more attention for his favourite topic. 'Every copy has interesting articles that address farmers problems through the use of modern and local methods of farming. However it is a pity that few articles are featured on livestock production. It is of little use to people engaged in animal production. Future editions should address this.' Don t stampede us, Mr Alede, but we get quite a lot of requests like this. In 2001, we had an opening article (Spore 94), six news items, five readers letters and 12 publications on livestock issues. Not enough, it seems, but we have to cover all sorts of topics for all sorts of aspects of farming and food. We shall try harder!Mr Alade from the Animal Science Department of the University of Maiduguri in Nigeria wants more attention for his favourite topic. 'Every copy has interesting articles that address farmers problems through the use of modern and local methods of..

    香溪河库湾春季水华期间浮游轮虫昼夜垂直分布及迁移的研究

    No full text
    为了了解香溪河库湾春季水华期间浮游轮虫的昼夜垂直分布和迁移情况及其影响因子,在春季甲藻(Peridiniopsis sp.)水华暴发期间,于2007年2月26日08:00至27日06:00对浮游轮虫的昼夜垂直分布进行调查研究。结果表明,轮虫虽在各个水层中均有分布,但是呈聚集分布形式。轮虫密度的垂直分布因种类和时间而异,优势种类广布多肢轮虫(Polyarthra vulgaris)、矩形龟甲轮虫(Keratella quadrata)和曲腿龟甲轮虫(Keratellavalga)白天都存在一定的垂直迁移运动,且都是先向下、再向上的迁移过程,夜晚则不存在垂直迁移现象,且聚集程度明显低于白天。光照强度的变化是轮虫垂直迁移运动的重要影响因子。由于溶解氧和叶绿素a的浓度都很高,二者对轮虫的昼夜垂直变化影响不显著

    香溪河库湾春季水华期间浮游轮虫昼夜垂直分布及迁移的研究

    No full text
    为了了解香溪河库湾春季水华期间浮游轮虫的昼夜垂直分布和迁移情况及其影响因子,在春季甲藻(Peridiniopsis sp.)水华暴发期间,于2007年2月26日08:00至27日06:00对浮游轮虫的昼夜垂直分布进行调查研究。结果表明,轮虫虽在各个水层中均有分布,但是呈聚集分布形式。轮虫密度的垂直分布因种类和时间而异,优势种类广布多肢轮虫(Polyarthra vulgaris)、矩形龟甲轮虫(Keratella quadrata)和曲腿龟甲轮虫(Keratellavalga)白天都存在一定的垂直迁移运动,且都是先向下、再向上的迁移过程,夜晚则不存在垂直迁移现象,且聚集程度明显低于白天。光照强度的变化是轮虫垂直迁移运动的重要影响因子。由于溶解氧和叶绿素a的浓度都很高,二者对轮虫的昼夜垂直变化影响不显著

    香溪河库湾春季水华期间浮游轮虫昼夜垂直分布及迁移的研究

    No full text
    为了了解香溪河库湾春季水华期间浮游轮虫的昼夜垂直分布和迁移情况及其影响因子,在春季甲藻(Peri-diniopsis sp.)水华暴发期间,于2007年2月26日08∶00至27日06∶00对浮游轮虫的昼夜垂直分布进行调查研究。结果表明,轮虫虽在各个水层中均有分布,但是呈聚集分布形式。轮虫密度的垂直分布因种类和时间而异,优势种类广布多肢轮虫(Polyarthra vulgaris)、矩形龟甲轮虫(Keratella quadrata)和曲腿龟甲轮虫(Keratella valga)白天都存在一定的垂直迁
    corecore