以香豆素为母体快速检测内源性甲醛的荧光探针

基于甲醛(FA)与肼易发生亲核加成反应,从而阻断肼与荧光母体间电子传递的光诱导电荷转移(PET)机理,设计合成了以香豆素为母体的甲醛荧光探针3-苯并噻唑-7-肼香豆素(Coun)。 实验结果显示,Coun与FA的最佳反应时间为4 min,极大地提高了检测效率,检测限为5×10^-6 μmol/L。 该探针具有良好的细胞膜通透性,可应用于生物领域,检测细胞内的甲醛含量。     

干扰背景非瑞利混响参数估计

提出了一种基于模糊统计归一化处理(FSNP)的K分布混响形状参数自适应估计方法。该方法首先对混响进行归一化处理,然后对不同归一化处理强度的处理数据进行形状参数估计,最后,取适中归一化处理强度数据形状参数估计值作为最终估计值。仿真结果表明,所提方法在参杂干扰背景和均匀背景下,都具有很好的参数估计性能。实测带宽4000 Hz声呐同区域混响参数估计结果显示,混响参杂强干扰时,所提方法形状参数估计值的最小值、最大值、标准差、极差分别为1.13,25.76, 4.36, 24.63,混响均匀时分别为2.54, 20.78, 3.84, 18.24。相比于传统抑制干扰和均匀背景参数估计算法,无论是同区域参杂干扰混响,还是均匀混响,所提方法参数估计结果的标准差和极差都明显下降。     

突发公共事件网络舆情引导研究

突发公共事件网络舆情是信息时代背景下比较重要的传播现象,在网络社交媒体不断发展的背景下,突发公共事件由于突发性、破坏性、公共性等特点引发的网络舆情也日益增加。突发公共事件网络舆情具有群体极化、标签效应、蝴蝶效应等特点,在进行网络舆情引导时往往需要结合其具体的效应特点,进行综合分析和讨论。面对突发公共事件舆情,需要主动进...     

锐钛矿型TiO2水溶胶的低温制备及其表征

Anatase titanium dioxide hydrosol was prepared at low temperature by a simple method. The title material was characterized by TEM, XRD, FTIR and BET, respectively. The photocatalytic activity of the as-prepared TiO₂ was evaluated by the degradation of methyl orange solution under sunlight and the photocatalytic oxidation of acetone in air. The results showed that the titanium dioxide hydrosol was composed of anatase phase with average grain size of about 7 nm, and the crystallinity became more perfect with the increase of temperature. The BET surface areas were more than 220 m²·g^-1 for these samples. It is found that the photocatalytic activity was much better for the higher heat processing temperature. Especially, the photocatalytic activity of the sample with a heat treatment of 110 ℃ was better than that of P25. In addition, TiO₂ hydrosol also possessed good photocatalytic activity under the sunlight illumination.     

高速A/D转换器ADS5400板级验证动态参数测试研究

某型号AD采集板调试故障率较高,经排查均与数字通道中AD器件ADS5400部分关键参数失效有关。本文通过开发板级测试系统,对ADS5400关键性能指标进行检测筛选,剔除了早期失效,显著改善了产品质量。     

COIL中碘气动阀可靠性增长试验的初步研究

对COIL中的碘气动阀进行可靠性增长试验,主要包括可靠性增长模型的讨论,试验方案设计、数据分析与处理等工作,提出了基于碘气动阀密封组件的改造措施,并进行了可靠性验证试验,试验结果表明经可靠性增长试验后,碘气动阀的可靠性有了较大提高。在此基础上分析得出了基于碘气动阀的可靠性增长模型。     

Physical properties and phase diagram of NaFe_(1-x)V_xAs

We grew a series of NaFe_1-xV_x As(0 ≤ x ≤ 0.03) single crystals and performed the measurements of resistance,magnetic susceptibility, and specific heat to study the superconducting phase diagram by doping V into Na Fe As. Both the structural and the spin-density-wave(SDW) transitions are slightly suppressed by V-doping. While superconducting transition temperature is enhanced to the maximum value of 15 K when the optimal doping level x = 0.007 and then is suppressed rapidly with further V-doping, displaying a small superconducting dome. Our results suggest that V-impurities should act as strong magnetic scattering centers which cause the sharp suppression of superconductivity in NaFe_1-xV_x As.     

紧缩场静区幅相性能现场校准系统

针对国内军用及民用各类型天线及目标特性测量常用的紧缩场静区平面波幅相性能现场校准需求,开展了0.3~110 GHz紧缩场现场校准系统的优化设计。研制了微波幅相收发系统、一体化接收探头天线和八自由度、高精确度可移动大型极坐标扫描设备(半径3 m,平面度均方根值0.04 mm),完成了大型紧缩场静区性能校准系统的研制。利用某航天单位的紧缩场对系统性能进行了现场试验验证,结果表明,研制的校准系统功能强,指标高,可以满足各类型紧缩场校准需求。     

AHP-模糊综合评价法在电视台频道部门绩效考核中的应用

本文以大众传媒绩效考核评价系为研发背景,从电视台频道绩效评价体系的制定入手,透过层次分析法和模糊综合评价法两种决策方法,探索一种适用于一般频道部门绩效考核的科学思路。     

超细长银纳米线的制备及其导电薄膜性能优化

以硝酸银为银源、聚乙烯吡咯烷酮(PVP)为形貌导向剂、硫酸铁为诱导剂、葡萄糖为还原剂,采用高效便捷的水热法制备银纳米线(AgNWs),通过调控PVP用量和热处理时间致使其长径比大于1000;将异丙醇与乙醇按照一定比例混合,配制出分散性良好的AgNWs墨水,并采用变速旋涂法在玻璃衬底上制备透明导电薄膜;通过低温低压烧结和聚乙烯醇(PVA)固化处理优化薄膜的光学及导电性能,制得方块电阻为(19±2)Ω·sq-1、透过率大于86;透明导电薄膜.