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21.
We present a simple method of guiding, distributing, and storing of a train of shape-dependent droplets by using side flows, cavity guiding tracks, and storage chambers. The squeezing flow makes a train of flattened droplets to align to one side of the wall and the pushing flow guides it to one of the designated guiding tracks. Then the guided droplets move along the guiding track due to the lowered surface energy when they flow along the track. In addition, simultaneous droplet guiding and storing process has been demonstrated. An array of storage chambers placed in each track could store each train containing differently concentrated droplets. The proposed method will be useful for distribution of droplets for further processes or storing for multiplex, large-scale, dynamic assays over time. 相似文献
22.
An external-cavity diode laser (ECDL) has been used to investigate pressure-induced self-broadening as well as frequency shift of 2v3 band R9 manifold of methane. A phase sensitivity detection technology has been employed to determine the pressure induced frequency shift coefficient, however, which is obtained by line shape analyses of the recorded absorption spectrum. F1 and F2 unresolved double lines near 6105.626 cm-1 were measured as an object because they are often used to the high sensitivity detection of trace methane. The results show that the self-broadening and pressure induced frequency shift coefficients are 0.0232±0.003 and 0.0055±0.0007 MHz/Pa, respectively. 相似文献
23.
Linfeng Wang 《中国科学 数学(英文版)》2018,61(5):943-954
In this paper, we work on compact quasi-Einstein metrics and prove several gap results. In the first part, we get a gap estimate for the first nonzero eigenvalue of the weighted Laplacian, by establishing a comparison theorem for the weighted heat kernel. In the second part, we establish two gap results for the Ricci curvature and the scalar curvature, based on which some rigid properties can be derived. 相似文献
24.
高温气冷堆燃料元件的基体石墨是一种多孔复合材料,是燃料元件的主要组成部分,其结构影响燃料元件的性能和裂变产物在燃料元件中的扩散。 本文利用压汞法表征基体石墨的孔隙结构,并讨论了基体石墨制备工艺中最大压制压强与热处理过程对孔隙结构的影响。 结果表明,基体石墨大孔孔径分布为6001900 nm,高温热处理使基体石墨的总孔隙率、中值孔径、大孔孔容均减小;基体石墨热处理样品的大孔孔容随最大压制压强的增加而呈线性减少,热处理过程单质Ag在石墨基体中的扩散速度与大孔孔容变化具有正相关性。 相似文献
25.
过渡金属磷化物电位低且比容量高, 是有发展前景的锂离子电池(LIBs)负极材料. 其中, ZnP2属于双活性负极材料, Zn与P都能与Li+发生反应, 储Li+性能更具有竞争力. 但是, 对于ZnP2的锂化机理及产物尚不明确. 采用第一性原理计算和电化学测试方法研究了ZnP2的电子性质和电化学性能, 通过理论计算和实验测试相结合阐述了ZnP2的锂化机制. 首先, 以密度泛函理论(DFT)计算揭示了ZnP2的锂化机理、Li+扩散路径、势垒和理论比容量(1477 mAh/g). 其次, 通过直流电弧等离子体法及固相烧结法合成ZnP2, 并测试其首圈放电曲线, 显示放电容量为1439 mAh/g, 与理论计算结果相近. 此外, 薄膜X射线衍射(XRD)检测最终产物成分为LiZn和Li3P, 与DFT计算结果一致. 相似文献
26.
1,2,3-Triazolium salts draw much attentions in recent years. We developed a new synthetic method to heteroatom-functionalized triazoliums via nucleophilic substitution of 4-bromomethyltriazolium. This method afforded triazoliums with different S, N, and O heteroatom-substituents. Moreover, SN2′ reaction was observed with alcohols or hydroxides. In addition, debromination and debromomethylation reaction occurred in some cases. 相似文献
27.
Cong Liu Chunshao Mo Linfeng Zhong Xiaoqi Gong Yang Zhang Xiaotong Wang Fan Yang Jing Li Prof. Jiang Lu Prof. Dingshan Yu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202312016
Here, we for the first time introduce ethoxylation chemistry to develop a new octupolar cyano-vinylene-linked 2D polymer framework (Cyano-OCF-EO) capable of acting as efficient mixed electron/ion conductors and metal-free sulfur evolution catalysts for dual-promoted Li and S electrochemistry. Our strategy creates a unique interconnected network of strongly-coupled donor 3-(acceptor-core) octupoles in Cyano-OCF-EO, affording enhanced intramolecular charge transfer, substantial active sites and crowded open channels. This enables Cyano-OCF-EO as a new versatile separator modifier, which endows the modified separator with superior catalytic activity for sulfur conversion and rapid Li ion conduction with the high Li+ transference number up to 0.94. Thus, the incorporation of Cyano-OCF-EO can concurrently regulate sulfur redox reactions and Li-ion flux in Li−S cells, attaining boosted bidirectional redox kinetics, inhibited polysulfide shuttle and dendrite-free Li anodes. The Cyano-OCF-EO-involved Li−S cell is endowed with excellent overall electrochemical performance especially large areal capacity of 7.5 mAh cm−2 at high sulfur loading of 8.7 mg cm−2. Mechanistic studies unveil the dominant multi-promoting effect of the triethoxylation on electron and ion conduction, polysulfide adsorption and catalytic conversion as well as previously-unexplored −CN/C−O dual-site synergistic effect for enhanced polysulfide adsorption and reduced energy barrier toward Li2S conversion. 相似文献
28.
Zongming Guo Linfeng Mei Fangshu Wan 《NoDEA : Nonlinear Differential Equations and Applications》2016,23(6):59
We obtain non-radial bifurcation from radial solutions of a semilinear elliptic equation in expanding annuli of \(\mathbb {R}^N\). To obtain the main results, we use a blow-up argument via the Morse index of the regular entire solutions of the equation The main results of this paper can be seen as applications of the properties of regular entire solutions of (0.1).
相似文献
$$\begin{aligned} -\Delta u=\lambda u^p \quad \text {in}\quad \mathbb {R}^N. \end{aligned}$$
(0.1)
29.
30.
Zhou Jiawen Zhu Weiya Zeng Miao Yang Qingqing Li Ping Lan Linfeng Peng Junbiao Li Yuan Huang Fei Cao Yong 《中国科学:化学(英文版)》2019,62(12):1656-1665
Stable radicals are challenging to prepare due to their intrinsic high reactivity. Herein, three trisphenolamine radicals were readily synthesized and exhibited unexpected thermal/electrochemical stability and semiconductor property. These three nitroxide radicals could be considered as a class of aromatized nitro groups or HNO_3 derivatives. The closed-shell nitro-like and open-shell nitroxide resonance structure contribute to their outstanding stability. Furthermore, the tunable ground states, extremely low band gap and p-type charge transport properties were systematically investigated. More importantly, the work presents the concept of aromatic inorganic acid radical(AIAR) and aggregation-induced radical(AIR) mechanism to understand the intrinsic structureproperty relationship of these radicals. In addition, we provide a novel strategy for the design of stable and low bandgap radicals for organic electronics, magnetics, spintronics, etc. 相似文献