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<jats:p>Lithium-ion battery packs are made by many batteries, and the difficulty in heat transfer can cause many safety issues. It is important to evaluate thermal performance of a battery pack in designing process. Here, a multiscale method combining a pseudo-two-dimensional model of individual battery and three-dimensional computational fluid dynamics is employed to describe heat generation and transfer in a battery pack. The effect of battery arrangement on the thermal performance of battery packs is investigated. We discuss the air-cooling effect of the pack with four battery arrangements which include one square arrangement, one stagger arrangement and two trapezoid arrangements. In addition, the air-cooling strategy is studied by observing temperature distribution of the battery pack. It is found that the square arrangement is the structure with the best air-cooling effect, and the cooling effect is best when the cold air inlet is at the top of the battery pack. We hope that this work can provide theoretical guidance for thermal management of lithium-ion battery packs.</jats:p>

<jats:p>Na-ion batteries (NIBs) have been attracting growing interests in recent years with the increasing demand of energy storage owing to their dependence on more abundant Na than Li. The exploration of the industrialization of NIBs is also on the march, where some challenges are still limiting its step. For instance, the relatively low initial Coulombic efficiency (ICE) of anode can cause undesired energy density loss in the full cell. In addition to the strategies from the sight of materials design that to improve the capacity and ICE of electrodes, presodiation technique is another important method to efficiently offset the irreversible capacity and enhance the energy density. Meanwhile, the slow release of the extra Na during the cycling is able to improve the cycling stability. In this review, we would like to provide a general insight of presodiation technique for high-performance NIBs. The recent research progress including the principles and strategies of presodiation will be introduced, and some remaining challenges as well as our perspectives will be discussed. This review aims to exhibit the basic knowledge of presodiation to inspire the researchers for future studies.</jats:p>

<jats:p>DNA polymerases are an essential class of enzymes or molecular motors that catalyze processive DNA syntheses during DNA replications. A critical issue for DNA polymerases is their molecular mechanism of processive DNA replication. We have proposed a model for chemomechanical coupling of DNA polymerases before, based on which the predicted results have been provided about the dependence of DNA replication velocity upon the external force on Klenow fragment of DNA polymerase I. Here, we performed single molecule measurements of the replication velocity of Klenow fragment under the external force by using magnetic tweezers. The single molecule data verified quantitatively the previous theoretical predictions, which is critical to the chemomechanical coupling mechanism of DNA polymerases. A prominent characteristic for the Klenow fragment is that the replication velocity is independent of the assisting force whereas the velocity increases largely with the increase of the resisting force, attains the maximum velocity at about 3.8 pN and then decreases with the further increase of the resisting force.</jats:p>

<jats:p>Using a procedure based on interpolation via continued fractions supplemented by statistical sampling, we analyze proton magnetic form factor data obtained via electron+proton scattering on <jats:italic>Q</jats:italic> <jats:sup>2</jats:sup> ∈ [0.027, 0.55] GeV<jats:sup>2</jats:sup> with the goal of determining the proton magnetic radius. The approach avoids assumptions about the function form used for data interpolation and ensuing extrapolation onto <jats:italic>Q</jats:italic> <jats:sup>2</jats:sup> ≃ 0 for extraction of the form factor slope. In this way, we find <jats:italic>r</jats:italic> <jats:sub>M</jats:sub> = 0.817(27) fm. Regarding the difference between proton electric and magnetic radii calculated in this way, extant data are seen to be compatible with the possibility that the slopes of the proton Dirac and Pauli form factors, <jats:italic>F</jats:italic> <jats:sub>1,2</jats:sub>(<jats:italic>Q</jats:italic> <jats:sup>2</jats:sup>), are not truly independent observables; to wit, the difference <jats:inline-formula> <jats:tex-math> <?CDATA $F{^{\prime} }_{1}(0)-F{^{\prime} }_{2}(0)/{\kappa }_{{\rm{p}}}=[1+{\kappa }_{{\rm{p}}}]/[4{m}_{{\rm{p}}}^{2}]$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>F</mml:mi> <mml:msub> <mml:mrow> <mml:mo>′</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy="false">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="false">)</mml:mo> <mml:mo>−</mml:mo> <mml:mi>F</mml:mi> <mml:msub> <mml:mrow> <mml:mo>′</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy="false">(</mml:mo> <mml:mn>0</mml:mn> <mml:mo stretchy="false">)</mml:mo> <mml:mrow> <mml:mo stretchy="false">/</mml:mo> </mml:mrow> <mml:msub> <mml:mrow> <mml:mi>κ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">p</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:mo stretchy="false">[</mml:mo> <mml:mn>1</mml:mn> <mml:mo>+</mml:mo> <mml:msub> <mml:mrow> <mml:mi>κ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">p</mml:mi> </mml:mrow> </mml:msub> <mml:mo stretchy="false">]</mml:mo> <mml:mrow> <mml:mo stretchy="false">/</mml:mo> </mml:mrow> <mml:mo stretchy="false">[</mml:mo> <mml:mn>4</mml:mn> <mml:msubsup> <mml:mrow> <mml:mi>m</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">p</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo stretchy="false">]</mml:mo> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpl_38_12_121401ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>, viz., the proton Foldy term.</jats:p>

<jats:p>A Stark decelerator can slow down polar molecules to very low velocities. When the velocities are very low, the number of cold molecules obtained is very small. In order to obtain a higher quantity of cold molecules, inspired by the work of Reens et al. [Phys. Rev. Res. 2 (2020) 033 095], we propose an alternative method of operating a Stark decelerator. Through the trajectory simulation of OH molecules in the decelerator, we find that the number of cold molecules can be greatly increased by one order of magnitude at both low and high final velocities on a Stark decelerator consisting of around 150 electrodes. This development is due to the improved longitudinal and the transverse focusing property provided by the new switching schemes and the high-voltage configurations on the decelerator unit.</jats:p>

<jats:p>We propose a method to retrieve the angle-dependent strong-field ionization of highest occupied molecular orbital (HOMO) from high-order harmonic generation (HHG) of aligned molecules. This method is based on the single-molecule quantitative rescattering model with known alignment distribution and photo-recombination cross sections of fixed-in-space molecules. With the macroscopic HHG of aligned N<jats:sub>2</jats:sub> molecules, we show that angle-dependent ionization of HOMO can be successfully retrieved at both low and high degrees of alignment. We then show that the error in the retrieved angular dependence of ionization becomes larger if the uncertainty in the alignment distribution is introduced in the retrieval procedure. We also examine that the retrieved ionization of HOMO is much deviated from the accurate one if the intensity of probe laser becomes higher such that inner HOMO-1 can contribute to HHG.</jats:p>

<jats:p>Taking heat positively as the information carrier, thermotronics can exempt the long-lasting thermal issue of electronics fundamentally, yet has been faced with the challenging multiplexing integration of diverse functionalities. Here, we demonstrate a spatiotemporal modulation platform to achieve multiplexing thermotronics functionalities based on the thermal-hysteresis vanadium dioxide, including negative-differential thermal emission, thermal diode, thermal memristor, thermal transistor, and beyond. The physics behind the multiplexing thermotronics lies in the thermal hysteresis emission characteristics of the phase-changing vanadium dioxide during the spatiotemporal modulation. The present spatiotemporal modulation is expected to stimulate more exploration on novel functionalities, system integration, and practical applications of thermotronics.</jats:p>

<jats:p>Room-temperature thermoelectric materials are important for converting heat into electrical energy. As a wide-bandgap semiconductor material, CuI has the characteristics of non-toxicity, low cost, and environmental friendliness. In this work, CuI powder was synthesized by a wet chemical method, then CuI film was formed by vacuum assisted filtration of the CuI powder on a porous nylon membrane, followed by hot pressing. The film exhibits a large Seebeck coefficient of 600 μV · K<jats:sup>−1</jats:sup> at room temperature. In addition, the film also shows good flexibility (∼95% retention of the electrical conductivity after being bent along a rod with a radius of 4 mm for 1000 times). A finger touch test on a single-leg TE module indicates that a voltage of 0.9 mV was immediately generated within 0.5 s from a temperature difference of 4 K between a finger and the environment, suggesting the potential application in wearable thermal sensors.</jats:p>

<jats:p>Lithium deposition on graphite electrode not only reduces fast-charging capability of lithium ion batteries but also causes safety trouble. Here, a low-field <jats:sup>7</jats:sup>Li dynamic nuclear polarization (DNP) is used to probe Li plating on the surfaces of three types of carbon electrodes: hard carbon, soft carbon and graphite. Owing to the strong Fermi contact interaction between <jats:sup>7</jats:sup>Li and conduction electrons, the <jats:sup>7</jats:sup>Li nuclear-magnetic-resonance (NMR) signal of Li metal deposited on electrode surface could be selectively enhanced by DNP. It is suggested that low-field <jats:sup>7</jats:sup>Li DNP spectroscopy is a sensitive tool for investigating Li deposition on electrodes during charging/discharging processes.</jats:p>

<jats:p>In recent years, great success has been achieved on the classification of symmetry-protected topological (SPT) phases for interacting fermion systems by using generalized cohomology theory. However, the explicit calculation of generalized cohomology theory is extremely hard due to the difficulty of computing obstruction functions. Based on the physical picture of topological invariants and mathematical techniques in homotopy algebra, we develop an algorithm to resolve this hard problem. It is well known that cochains in the cohomology of the symmetry group, which are used to enumerate the SPT phases, can be expressed equivalently in different linear bases, known as the resolutions. By expressing the cochains in a reduced resolution containing much fewer basis than the choice commonly used in previous studies, the computational cost is drastically reduced. In particular, it reduces the computational cost for infinite discrete symmetry groups, like the wallpaper groups and space groups, from infinity to finity. As examples, we compute the classification of two-dimensional interacting fermionic SPT phases, for all 17 wallpaper symmetry groups.</jats:p>