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1.
通过改装多旋翼无人机(UAV)和搭载各类载荷以及联合地基观测设备对大柴旦地区大气、环境以及气溶胶参数进行测量。利用获得的数据资料,对该地区近地层气溶胶粒子数浓度(即单位体积空气中气溶胶粒子的数目)、消光系数以及气象要素等特征进行了分析。结果表明,在大柴旦地区,近地层气溶胶粒子数浓度日变化显著,呈现双峰形态,气溶胶粒子数浓度的变化范围为75~220 cm-3,消光系数的变化范围为0.004~0.038 km-1;当风速小于6 m/s时,气溶胶粒子数浓度与风速呈负相关关系;当风速大于6 m/s时,二者呈正相关关系;相对湿度对气溶胶粒子的影响较小,这可能是由于该地区以沙尘型气溶胶为主,吸湿性较弱。本研究基于多旋翼无人机探测平台,可以有效地获得近地层精细化大气、环境结构,有助于研究人员了解该地区气溶胶的结构、变化特征以及建立气溶胶模式,同时也为气溶胶及大气环境参数探测方法提供了技术支撑及思路拓展。 相似文献
2.
Yin Qingqing Xu Fen Sun Lixian Li Yaying Liao Lumin Wang Tao Guan Yanxun Xia Yongpeng Zhang Chenchen Wei Sheng Zhang Huanzhi Li Bin 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6583-6592
Journal of Thermal Analysis and Calorimetry - Polyethylene glycol (PEG) is widely used as phase change materials (PCMs). However, the leakage and low thermal conductivity issues restrict its... 相似文献
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5.
Dr. Qing Xu Dr. Shanshan Tao Dr. Qiuhong Jiang Prof. Donglin Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4587-4593
A strategy based on covalent organic frameworks for ultrafast ion transport involves designing an ionic interface to mediate ion motion. Electrolyte chains were integrated onto the walls of one-dimensional channels to construct ionic frameworks via pore surface engineering, so that the ionic interface can be systematically tuned at the desired composition and density. This strategy enables a quantitative correlation between interface and ion transport and unveils a full picture of managing ionic interface to achieve high-rate ion transport. Moreover, the effect of interfaces was scaled on ion transport; ion mobility is increased in an exponential mode with the ionic interface. This strategy not only sets a benchmark system but also offers a general guidance for designing ionic interface that is key to systems for energy conversion and storage. 相似文献
6.
通过微波法制备了CaMoO4:Tb3+,Eu3+白色荧光粉.采用X射线粉末衍射仪、扫描电子显微镜和荧光光谱仪对样品材料的结构、形貌和发光性能进行了表征.分别讨论了在不同助剂、不同反应浓度、不同反应温度及稀土离子Eu3+和Tb3+共掺比例变化对荧光粉的发光性能的影响.结果表明:不加活性剂所得CaMoO4:Tb3+,Eu3+样品在反应浓度为0.06 mol/L、反应温度为120℃时发光性能最好;通过调节CaMoO4:Tb3+,Eu3+荧光粉中稀土离子Eu3+和Tb3+共掺比例荧光粉的发光颜色可以很容易地从冷白光变为暖白光. 相似文献
7.
Removal of iodate from aqueous solution using diatomite/nano titanium dioxide composite as adsorbent
Liu Piao Chen Tao Zheng Jin-guang 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1179-1188
Journal of Radioanalytical and Nuclear Chemistry - Highly deficient strontium cobaltite (SrCoOx), as a new nanomaterial that is thermally treated at low temperature... 相似文献
8.
Jinhua Gao Yuanfang Tao Dr. Jian Zhang Nannan Wang Xin Ji Dr. Jinling He Prof. Yubing Si Prof. Weili Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11246-11256
Our previous discovery suggested that substituents on the 1,7 positions delicately modulate the sensing ability of the meso-arylmercapto boron-dipyrromethene (BODIPY) to biothiols. In this work, the impact of delicate modulations on the sensing ability is investigated. Therefore, 1,7-dimethyl, 3,5-diaryl substituted BODIPY is designed and developed and its conformationally restricted species with a meso-arylmercapto moiety ( DM-BDP-SAr and DM-BDP-R-SAr ) as selective fluorescent probes for Cys. Moreover, the lysosome-target probes ( Lyso-S and Lyso-D ) based on DM-BDP-SAr carrying one or two morpholinoethoxy moieties were developed. They were able to detect Cys selectively in vitro with low detection limits. Both Lyso-S and Lyso-D localized nicely in lysosomes in living HeLa cells and exhibited red fluorescence for Cys. Moreover, a novel fluorescence quenching mechanism was proposed from the calculations by density functional theory (DFT). The probes may go through intersystem crossing (from singlet excited state to triplet excited state) to result in fluorescence quenching. 相似文献
9.
Introducing plasmonic metals into semiconductor materials has been proven to be an attractive strategy for enhancing photocatalytic activity in the visible region. In this work, a novel and efficient Ag/Ag2WO4/g‐C3N4 (AACN) ternary plasmonic photocatalyst was successfully synthesized using a facile one‐step in situ hydrothermal method. The composition, structure, morphology and optical absorption properties of AACN were investigated using X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and UV–visible diffuse reflectance spectroscopy, respectively. Photocatalytic performance of AACN was evaluated via rhodamine B and tetracycline degradation. The results indicated that AACN had excellent photocatalytic performance for rhodamine B degradation with a rate constant of 0.0125 min?1, which was higher than those of Ag2WO4 and Ag/Ag2WO4. Characterization and photocatalytic tests showed that the strong coupling effect between the Ag/Ag2WO4 nanoparticles and the exfoliated ultrathin g‐C3N4 nanosheets was superior for visible‐light responsivity and reduced the recombination rate of photogenerated electrons and holes. A proposed mechanism is also discussed according to the band energy structure and the experimental results. 相似文献
10.
现有考核评价方式侧重期末考试而忽略过程考核,结合材料力学课程,探索一套注重过程考核的评价体系,综合评价学生对本课程的掌握程度,即将期末考试成绩在总评中的占比由70%降低至50%,平时作业、随堂测验、模块测验、实验考核和案例分析成绩各占比10%。新评价方式更加注重对学生学习过程的考核,使学生在整个课程学习过程中保持高度紧张感,提高学习的时效性和目的性,进而提高学生学习材料力学的热情和材料力学课堂教学效果。 相似文献