Facile and sustainable synthesis of sodium lignosulfonate derived carbon quantum dots for the detection of total Mn and ascorbic acid

A fluorescent nanoprobe based on sodium lignosulfonate derived carbon quantum dots (SLS-CQDs) was fabricated through a facile and sustainable one-step hydrothermal treatment. The obtained SLS-CQDs had excellent fluorescence properties and were applied to detect total Mn and ascorbic acid (AA). The fluorescence of SLS-CQDs could be effectively quenched by Mn based on a static quenching process and recovered by the addition of AA. An “on–off-on” fluorescent nanoprobe was established to determine total Mn and AA with the detection limits of 6.9 µg/L and 0.65 µM with the corresponding linear ranges of 0.25–2.25, 5–25 mg/L, and 5–110 µM, respectively. This nanoprobe could accurately detect total Mn in surface water and AA in Vitamin C effervescent tablet samples. The proposed method is simple and can be performed easily, indicating that SLS-CQDs might be used in environmental monitoring, food and drug testing.     

基于大气偏振光特性辅助定向的自主导航方法

针对惯性系统(INS)与卫星组合导航容易受到干扰的局限性,为提高海上作战船舰的自主导航能力,提出基于全天域大气偏振光特性辅助定向自主导航方法。在分析全天域偏振光中性点的运动规律的基础上,采用两点一线原理使用中性点确定载体航向角并结合电磁计程仪(LOG)测得的航速信息辅助惯性系统进行导航,采用卡尔曼滤波最优算法对组合导航系统进行了信息融合。matlab仿真结果表明基于全天域偏振光中性点/LOG/INS组合导航方法能够有效抑制INS导航定位误差,使船舰航向角误差稳定在0.6,水平速度误差稳定在0.7 m/s,水平位置误差稳定在10 m,增强了船舰的自主导航性能,并且具有高度的隐蔽性和抗干扰能力,具有一定的军事工程应用价值     

经由和型算子方法下共形分数阶微分方程正解的唯一性和迭代序列

本文研究了一类共形分数阶微分方程两点边值问题,通过利用定义在锥上的一类和型算子不定点定理,获得了微分方程正解存在唯一性,并构造一个迭代序列逼近唯一正解.最后,通过两个例子验证了本文获得的主要结论.     

Microwave synthesis of NiSe2 nanomaterials on carbon fiber felt for flexible supercapacitors and oxygen evolution reaction

Journal of Solid State Electrochemistry - In this paper, NiSe2 materials were synthesized on carbon fiber felts (CFF) using a convenient one-step microwave approach. Self-supporting NiSe2/CFF is a...