Investigation on the Structure and Dynamics of Lithium Ion Solvation Shell by Linear and Non-Linear Infrared Spectroscopy

Lithium ion battery (LIB) is a lightweight, rechargeable and powerful battery that is used widely from mobile phones to laptops to electric cars. It has many exceptional advantages such as high energy density, high output power, relatively low self-discharge, etc. However, it has some disadvantages such as safety issues, capacity loss, and expensive manufacture. LIB is composed of three main components: electrolytes, positive and negative electrodes. Researchers have been working on improving the performance of LIB for the past decade, but only a few have focused on investigating the electrolytes at the molecular level. In addition, the molecular mechanisms behind the macroscopic properties of LIB are yet to be explored. The vibrational stretch of the solvent molecule is selected as the infrared probe in order to investigate the structure and dynamics in LIE at the molecular level via linear and non-linear infrared spectroscopies. Ultrafast laser spectroscopy has emerged as a powerful tool of studying the structure and dynamics at the molecular level because it offers unique advantages of time and frequency resolutions. DFT calculation, classical and ab initio MD simulations are also employed to assist the interpretation of experimental data. Three projects of LIE are detailed in this dissertation. The first project focused on lowering the flammability of the electrolyte by replacing carbonate solvent with urea solvent, where it is found that the molecular interactions in urea-based electrolytes are similar to the carbonate-based electrolytes. The aim of second project was to reveal the molecular mechanism behind the dynamics of solvent molecules around Li ion in acetonitrile-based electrolytes, where it is shown that the angle between Li ion and acetonitrile plays the most important role in the molecular dynamics around Li ion. The last project investigated a less conventional LIE, which is the concentrated electrolyte composed of Li sulfonylimide salt and acetonitrile, where a highly correlated network is proposed to form in the mixtures. In addition, the molecular origin of the macroscopic properties in a family of concentrated electrolytes is studied through both experimental and theoretical methods

Space-and-time-synchronized simultaneous vehicle tracking/formation using cascaded prescribed-time control

In this paper, we present a space-and-time-synchronized control method with application to the simultaneous tracking/formation. In the framework of polar coordinates, through correlating and decoupling the reference/actual kinematics between the self vehicle and target, time and space are separated, controlled independently. As such, the specified state can be achieved at the predetermined terminal time, meanwhile, the relative trajectory in space is independent of time. In addition, for the stabilization before the predesigned time, a cascaded prescribed-time control theorem is provided as the preliminary of vehicle tracking control. The obtained results can be directly extended to the simultaneous tracking/formation of multiple vehicles. Finally, numerical examples are provided to verify the effectiveness and superiority of the proposed scheme.Comment: 10 pages, 5 figures. International Journal of Robust and Nonlinear Control 202

CircZNF652 accelerates the proliferation and migration of primary lung carcinoma cells by downregulating miR-766

Purpose: To explore the biological functions and molecular mechanism of circZNF652 involvement in primary lung carcinoma.Methods: CircZNF652 levels in primary lung carcinoma cases and controls were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Its prognostic value in primary lung carcinoma was examined by depicting it with Kaplan-Meier curves. The biological functions of circZNF652 in regulating proliferative and migratory capacities in A549 and SPC-A-1 cells were analyzed from the curves. Interaction between circZNF652 and its downstream gene, miR-766, wasassessed, and their co-regulation on primary lung carcinoma was determined by rescue experiments.Results: CircZNF652 was abnormally and significantly upregulated in primary lung carcinoma cases (p< 0.05), resulting in a poor prognosis. The knockdown effect of circZNF652 attenuated the proliferative and migratory capacities of A549 and SPC-A-1 cells, and downregulated epithelial-mesenchymal transition (EMT)-associated genes. CircZNF652 bound and negatively regulated miR-766, a keydownstream gene involved in circZNF652-induced aggravation of primary lung carcinoma.Conclusion: CircZNF652 serves as an oncogene, triggering the aggravation of primary lung carcinoma by negatively regulating miR-766. The results of this study may provide new insights into the treatment of lung carcinoma

A Numerical Study of Heat and Mass Transfer in Porous-Fluid Coupled Domains

Ph.DDOCTOR OF PHILOSOPH

Reconfi guration analysis of carrier security system for IPv6

With the continuous development of the Internet, IPv6 planning and deployment has become the current “accelerate the construction of network power, to win the future international competition of new advantages” an urgent requirement, and the current security system reconstruction in the implementation of IPv6 planning and deployment plan has a very important practical promotion signifi cance. However, we should pay attention to one point is that compared with the Internet construction and operation and maintenance, the operator IPv6 network construction and its security operation and maintenance is a certain difference. Therefore, based on the background of the new era, it is very necessary to actively explore the path of IPv6 oriented carrier security system reconstruction planning. Based on this, this paper fi rst describes the application advantages of IPv6, and briefl y analyzes the status quo of the carrier security system, and discusses the reconstruction direction and planning of the IPv6 oriented carrier security system, for reference only

The Application of OCTA in Assessment of Anti-VEGF Therapy for Idiopathic Choroidal Neovascularization

Purpose. To assess the morphology of idiopathic choroidal neovascularization (ICNV) by optical coherence tomography angiography (OCTA) and determine the therapeutic effects of intravitreal antivascular endothelial growth factor (anti-VEGF). Method. Patients with naive ICNV were assessed by spectral domain optical coherence tomography (SD-OCT) and OCTA in this observational study. The timing of observation was before treatment, 1 day after treatment with intravitreal anti-VEGF injection, and 1 month after the treatment. The central retina thickness (CRT) on SD-OCT, selected CNV area, and flow area on OCTA were measured. Results. A total of 17 eyes from 17 patients with ICNV were included in this study. OCTA showed visible irregular choroidal neovascularization with “tree-in-bud” form on outer retinal layer. After treatment, as well as in the 1-day follow-up, CNV decreased in size from the periphery, and the vessel density was reduced. As shown on OCTA, the selected CNV area and flow area were significantly reduced compared to pretreatment. The rate of CNV vessel area changes was higher on OCTA than the changes in CRT on SD-OCT at 1-day and 1-month follow-up. Conclusion. Intravitreal injection of anti-VEGF is effective for idiopathic choroidal neovascularization, and the treatment outcomes are observable after 1 day. OCTA provides a useful approach for monitoring and evaluating the treatment of intravitreal anti-VEGF for CNV

Controlled pumping of matter-wave solitons in a one-dimensional optical superlattice

We study the pumping of matter-wave solitons formed in Bose-Einstein condensates (BECs) with attractive atomic interactions that are loaded into optical superlattices in which one of the lattices is moving with respect to the other. We find that solitons exhibit the remarkably similar pumping properties in both shallow and deep lattices, and that for exactly the same soliton initially excited, switching between integer (fractional) pumping and trapping can be achieved by simply adjusting the lattice parameters. In addition, we find that the gap solitons, which bifurcate from the lowest energy band in a semi-infinite band gap, also exhibit this lattice-parameter-dependent pumping and trapping. The treatment of solitons as classical particles with effective centre-of-mass equations of motion provides a good description of this parameter-dependent integer (fractional) pumping and trapping of solitons.Comment: 11 pages,13 figure

Assessing the Location of Ionic and Molecular Solutes in a Molecularly Heterogeneous and Nonionic Deep Eutectic Solvent

Copyright © 2020 American Chemical Society. Deep eutectic solvents (DES) are emerging sustainable designer solvents viewed as greener and better alternatives to ionic liquids. Nonionic DESs possess unique properties such as viscosity and hydrophobicity that make them desirable in microextraction applications such as oil-spill remediation. This work builds upon a nonionic DES, NMA-LA DES, previously designed by our group. The NMA-LA DES presents a rich nanoscopic morphology that could be used to allocate solutes of different polarities. In this work, the possibility of solvating different solutes within the nanoscopically heterogeneous molecular structure of the NMA-LA DES is investigated using ionic and molecular solutes. In particular, the localized vibrational transitions in these solutes are used as reporters of the DES molecular structure via vibrational spectroscopy. The FTIR and 2DIR data suggest that the ionic solute is confined in a polar and continuous domain formed by NMA, clearly sensing the direct effect of the change in NMA concentration. In the case of the molecular nonionic and polar solute, the data indicates that the solute resides in the interface between the polar and nonpolar domains. Finally, the results for the nonpolar and nonionic solute (W(CO)6) are unexpected and less conclusive. Contrary to its polarity, the data suggest that the W(CO)6 resides within the NMA polar domain of the DES, probably by inducing a domain restructuring in the solvent. However, the data are not conclusive enough to discard the possibility that the restructuring comprises not only the polar domain but also the interface. Overall, our results demonstrate that the NMA-LA DES has nanoscopic domains with affinity to particular molecular properties, such as polarity. Thus, the presented results have a direct implication to separation science