[en] Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [³H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [³H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

[en] Highlights: • Favorable regulatory policies are related 2.8 more start-ups and 1.6 more new subsidiaries. • Licensing policies are related to 2 fewer start-ups and 0.5 fewer new subsidiaries. • The relationship between financial incentives and new firm formation is not robust. • The distributional implication of policies indicates the importance of considering the fairness of policies in policy design. The relationship between energy policies and entrepreneurship has long been a keen interest of researchers and policymakers. This study seeks to understand whether and how public policies affect—promote or hinder—the founding of new firms by examining the impact of solar regulatory and financial incentive policies on two types of new firm formation (i.e., start-ups and new subsidiaries) in the U.S. solar photovoltaic (PV) installation industry. This study finds that favorable regulatory policies are associated with an increased number of 2.8 start-ups and 1.6 new subsidiaries, and restrictive regulations (i.e., licensing policies) are associated with 2 fewer start-ups and 0.5 fewer new subsidiaries in a state. This study also finds that third-party ownership policy seems to have no impact on new firm formation. Furthermore, the relationship between financial incentives and new firm formation is not robust. This study suggests that policies that create a favorable business environment (or increase the barriers to business entry) may benefit (or hinder) different types of firms to varying degrees, as firms may have different levels of motivations, incentives, resources, and capacity to leverage these policies. Therefore, the distributional implications of policies should be taken into account in policy designs.

[en] We investigate the kurtosis and skewness of net-baryon number fluctuations in the Polyakov loop extended Nambu-Jona-Lasinio (PNJL) model, and discuss the relations between fluctuation distributions and the phase structure of quark-gluon matter. The calculation shows that the traces of chiral and deconfinement transitions can be effectively reflected by the kurtosis and skewness of net-baryon number fluctuations not only in the critical region but also in the crossover region. The contour plot of baryon number kurtosis derived in the PNJL model can qualitatively explain the behavior of net-proton number kurtosis in the STAR beam energy scan experiments. Moreover, the three-dimensional presentations of the kurtosis and skewness in this study are helpful to understand the relations between baryon number fluctuations and QCD phase structure. (orig.)

[en] We choose a Si/Ge interface as a research object to investigate the influence of interface disorder on thermal boundary conductance. In the calculations, the diffuse mismatch model is used to study thermal boundary conductance between two non-metallic materials, while the phonon dispersion relationship is calculated by the first-principles density functional perturbation theory. The results show that interface disorder limits thermal transport. The increase of atomic spacing at the interface results in weakly coupled interfaces and a decrease in the thermal boundary conductance. This approach shows a simplistic method to investigate the relationship between microstructure and thermal conductivity. (general)

[en] In this paper, Mn:ZnSe/ZnS core/shell-doped quantum dots (d-dots) with 3-mercaptopropionic acid as the stabilizer are successfully synthesized through a simple one-pot synthesis procedure in aqueous solution. The average diameter of Mn:ZnSe/ZnS core/shell d-dots is about 2.9 nm, which is lager than that of Mn:ZnSe cores (about 1.9 nm). The optical features and structure of the obtained Mn:ZnSe/ZnS core/shell quantum dots have been characterized by UV–Vis and fluorescence spectroscopy, X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The photostability against UV irradiation and chemical stability against H₂O₂ etching have been studied, and the results showed that the prepared Mn:ZnSe/ZnS core/shell d-dots are more stable than CdTe quantum dots prepared in aqueous solution. Finally, the resulting core/shell quantum dots are used as fluorescent label in human osteoblast-like HepG2 cell imaging.

[en] Highlights: • Mechanical alloying process led to the formation of crystal Al(Fe) solid solution. • A degradation efficiency of 99% for X-3B was achieved within only a few min under Al-Fe alloys treatment process. • The electrochemical corrosion processes of the Al-Fe alloys significantly promote the degradation reaction. • The degradation of the X-3B solution was fit to the zero-order kinetic model. The present study described the excellent degrading ability of as-synthesized Al-Fe alloys for degradation of high-concentration X-3B in high salinity, alkaline aqueous solutions and its degradation mechanism. Al-Fe alloys were prepared by high-energy ball-milling of pure Fe and Al powders and further characterized by XRD, SEM, and BET. The results showed that the mechanical alloying process led to the formation of crystal Al(Fe) solid solution. Batch experimental results confirmed that a high concentration of X-3B could be completely removed from an aqueous solution with 2 g/L Al-Fe alloy particles within 3 min. The degradation of X-3B followed zero-order kinetics, for initial dye concentrations value from 100 to 2000 mg/L. The major factors that affect the degradation of X-3B were also investigated. Furthermore, the intermediate products were identified via UV–vis, FTIR, and GC–MS analysis, and the potential mechanism was discussed. It was also found that the biodegradability, as expressed by the BOD₅/COD ratio, was significantly increased following the degradation reaction. Therefore, the Al-Fe alloys system was confirmed as an effective and simple strategy for the pre-treatment of azo dye wastewater.

[en] Highlights: • The coupled effect of buoyancy and EHD forces on convection melting are studied. • An unified lattice Boltzmann model is extended to solving EHD melting. • The onset of convective flow and its transient evolution are tracked. • An approximate scaling law of heat transfer (Nu) is concluded based on results. • A maximum 60% of melting time saving can be observed under EHD. In this study, a lattice Boltzmann method (LBM) is extended for the problem of electrohydrodynamic (EHD) solid-liquid phase change in a square cavity. Four unified lattice Boltzmann equations (LBEs) are used to solve the fully coupled mathematical equations, including the Navier-Stokes equations, the energy conservation equation, the Poisson’s equation and the charge conservation equation. We first validate the numerical simulation by three cases in the hydrostatic state and two cases of natural convection melting in a square cavity. The numerical solution of the EHD melting is then presented entirely with a detailed analysis of the mechanisms of EHD enhancement. Results show that, for heating and injection from below, EHD enhances heat transfer by modifying the onset of the flow motion in the liquid zone; whereas for heating and injection from left side, strong enough Coulomb force will lead to the transition of the convection rolls which increases heat transfer at later times of the melting. With the analysis of melting dynamics with varying Rayleigh number Ra, we show that the buoyancy force which was neglected in previous EHD melting problems plays an important role in destabilizing the dynamical system and increasing heat transfer, especially for the case of melting from left. We also investigate the dependence of heat transfer enhancement on electric Rayleigh number Ta, and it is found that the melting time is indeed a decreasing function of Ta. When the values of Ta are high enough, the heat transfer becomes almost independent of Rayleigh number.

[en] Silver nanoparticle thin films with different average particle diameters are grown on silicon substrates. Boron nitride thin films are then deposited on the silver nanoparticle interlayers by radio frequency (RF) magnetron sputtering. The boron nitride thin films are characterized by Fourier transform infrared spectra. The average particle diameters of silver nanoparticle thin films are 126.6, 78.4, and 178.8 nm. The results show that the sizes of the silver nanoparticles have effects on the intensities of infrared spectra of boron nitride thin films. An enhanced infrared absorption is detected for boron nitride thin film grown on silver nanoparticle thin film. This result is helpful to study the growth mechanism of boron nitride thin film. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

[en] The influences of initial microstructures on the mechanical properties and the recrystallization texture of magnetostrictive 0.1at% NbC-doped Fe₈₃Ga₁₇ alloys were investigated. The directionally solidified columnar-grained structure substantially enhanced the tensile elongation at intermediate temperatures by suppressing fracture along the transverse boundaries. Compared with tensile elongations of 1.0% at 300°C and 12.0% at 500°C of the hot-forged equiaxed-grained alloys, the columnar-grained alloys exhibited substantially increased tensile elongations of 21.6% at 300°C and 46.6% at 500°C. In the slabs for rolling, the introduction of <001>-oriented columnar grains also promotes the secondary recrystallization of Goss grains in the finally annealed sheets, resulting in an improvement of the saturation magnetostriction. For the columnar-grained specimens, the inhomogeneous microstructure and disadvantage in number and size of Goss grains are improved in the primarily annealed sheets, which is beneficial to the abnormal growth of Goss grains during the final annealing process.

[en] Lithium–sulfur battery possesses a high energy density; however, its application is severely blocked by several bottlenecks, including the serious shuttling behavior and sluggish redox kinetics of sulfur cathode, especially under the condition of high sulfur loading and lean electrolyte. Herein, hollow molybdate (CoMoO${}_4$, NiMoO${}_4$, and MnMoO${}_4$) microspheres are introduced as catalytic hosts to address these issues. The molybdates present a high intrinsic electrocatalytic activity for the conversion of soluble lithium polysulfides, and the unique hollow spherical structure could provide abundant sites and spatial confinement for electrocatalysis and inhibiting shuttling, respectively. Meanwhile, it is demonstrated that the unique adsorption of molybdates toward polysulfides exhibits a "volcano-type" feature with the catalytic performance following the Sabatier principle. The NiMoO${}_4$ hollow microspheres with moderate adsorption show the highest electrocatalytic activity, which is favorable for enhancing the electrochemical performance of sulfur cathode. Especially, the S/NiMoO${}_4$ composite could achieve a high areal capacity of 7.41 mAh cm${}^{-<!--\; ???\; -->2}$ (906.2 mAh g${}^{-<!--\; ???\; -->1}$) under high sulfur loading (8.18 mg cm${}^{-<!--\; ???\; -->2}$) and low electrolyte/sulfur ratio (E/S, 4 µL mg${}^{-<!--\; ???\; -->1}$). This work offers a new perspective on searching accurate rules for selecting and designing effective host materials in the lithium–sulfur battery. (© 2021 Wiley-VCH GmbH)