Droplet-Based Microfluidic Preparation of Shape-Variable Alginate Hydrogel Magnetic Micromotors

This article introduces a facile droplet-based microfluidic method for the preparation of Fe3O4-incorporated alginate hydrogel magnetic micromotors with variable shapes. By using droplet-based microfluidics and water diffusion, monodisperse (quasi-)spherical microparticles of sodium alginate and Fe3O4 (Na-Alg/Fe3O4) are obtained. The diameter varies from 31.9 to 102.7 µm with the initial concentration of Na-Alginate in dispersed fluid ranging from 0.09 to 9 mg/mL. Calcium chloride (CaCl2) is used for gelation, immediately transforming Na-Alg/Fe3O4 microparticles into Ca-Alginate hydrogel microparticles incorporating Fe3O4 nanoparticles, i.e., Ca-Alg/Fe3O4 micromotors. Spherical, droplet-like, and worm-like shapes are yielded depending on the concentration of CaCl2, which is explained by crosslinking and anisotropic swelling during the gelation. The locomotion of Ca-Alg/Fe3O4 micromotors is activated by applying external magnetic fields. Under the rotating magnetic field (5 mT, 1–15 Hz), spherical Ca-Alg/Fe3O4 micromotors exhibit an average advancing velocity up to 158.2 ± 8.6 µm/s, whereas worm-like Ca-Alg/Fe3O4 micromotors could be rotated for potential advancing. Under the magnetic field gradient (3 T/m), droplet-like Ca-Alg/Fe3O4 micromotors are pulled forward with the average velocity of 70.7 ± 2.8 µm/s. This article provides an inspiring and timesaving approach for the preparation of shape-variable hydrogel micromotors without using complex patterns or sophisticated facilities, which holds potential for biomedical applications such as targeted drug delivery.

A Shape-Variable, Aqueous, Low-Temperature Liquid Metal–Conductive Polymer Secondary Battery

A shape-variable aqueous secondary battery operating at low temperature is developed using Ga68In22Sn10 in wt% liquid metal anode and conductive polymer (polyaniline (PANI)) cathode. While in the GaInSn alloy anode, Ga is the active constituent; Sn and In increase the acid resistance and decrease the eutectic point to -19°C. This enables the use of strongly acidic aqueous electrolytes (here, pH 0.9), thereby improving the activity and stability of the PANI cathode. Consequently, the battery exhibits remarkable excellent electrochemical performance and mechanical stability. The GaInSn–PANI battery operates via a hybrid mechanism of Ga3+ stripping/plating and Cl− insertion/extraction and delivers a high initial capacity of over 324.6 mAh g− 1 and a 52.4% retention rate at 0.2 A g− 1 after 500 cycles, and outstanding power and energy densities of 4300 mW g− 1 and 98.7 mWh g− 1, respectively. Because of the liquid anode, the battery without packaging can be deformed with a small force of several millinewtons without any capacity loss. Moreover, at approximately − 5°C, the battery delivers a capacity of 67.8 mAh g− 1 at 0.2 A g− 1 with 100% elasticity. Thus, the battery is promising as a deformable energy device at low temperatures and in demanding environments.

Energy-energy correlation in hadronic Higgs decays: analytic results and phenomenology at NLO

In this work we complete the investigation of the recently introduced energy-energy correlation (EEC) function in hadronic Higgs decays at next-to-leading order (NLO) in fixed-order perturbation theory in the limit of vanishing light quark masses. The full analytic NLO result for the previously unknown EEC in the H → $$ q\overline{q} $$ q q ¯ + X channel is given in terms of classical polylogarithms and cross-checked against a numerical calculation. In addition to that, we discuss further corrections to predictions of the Higgs EEC event shape variable, including quark mass corrections, effects of parton shower and hadronization. We also estimate the statistical error on the measurements of the Higgs EEC at future Higgs factories and compare with the current perturbative uncertainty.

Prediction of MTTF of Rotary Microcryogenic Gas Machines (Microcryocoolers) based on the Weibull Distribution Law

In this paper, we analyze the methods for predicting the MTTF of microcryocoolers of various manufacturers based on the Weibull law. The values of the shape and scale parameters of the Weibull distribution law for rotary microcryocoolers of various foreign manufacturers and a method for calculating the shape and scale parameters of this law are applied to the data obtained from experimental studies of microcryocooler samples. The limiting values of the shape variable were estimated and the methods for calculating the scale parameter needed to predict the MTTF of the microcryocooler both at the stage of improving existing models and at the stage of designing newly developed samples are presented. It seems that the approach to predicting the MTTF of the microcryocooler described in the work will allow us to determine the parameters of the Weibull distribution function for specific values set by the customer of the MTTF of the created microcryocooler sample, which in turn will allow the selection of machine components (assemblies and details) also for a specific values of MTTF

Soft-Collinear Effective Theory

The lectures that appear within this chapter provide an introduction to soft-collinear effective theory (SCET). It begins by discussing resummation for soft-photon effects in QED, including soft photons in electron–electron scattering and the expansion of loop integrals and the method of regions event-shape variables. It then covers SCET specifically, including the method of regions for the Sudakov form factor, effective Lagrangians, the vector current in SCET, and resummation by renormalization group (RG) evolution. It covers applications of SCET in jet physics, describes the characteristic feature in jet processes of Sudakov logarithms, and discusses factorization for the event-shape variable thrust and factorization and resummation for jet cross sections.