Water-based green deep eutectic solvent: Application in liquid-liquid microextraction of trace bisphenol A in edible oils.

In this study, tetrabutylammonium chloride (TBAC), tetrabutylammonium bromide (TBAB), and choline chloride (ChCl) were innovatively applied in the liquid-liquid microextraction (LLME) of bisphenol A (BPA) from edible oil by forming water-based deep eutectic solvent (WDES). The presence of water is not only used in the synthesis of WDES, but also modulates the viscosity of DES and improve its diffusion and mass transfer properties. Several crucial parameters affecting the extraction efficiency were examined, including the type and amount of WDES and the extraction time.

Net energy of grains for dairy goats differed with processing methods and grain types.

Background: The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion, thereby impacting energy utilization. This study aimed to explore the impact of grain variety and processing methods on the net energy (NE) in dairy goats, analyzing these effects at the level of nutrient digestion and metabolism.

Methods: Eighteen castrated Guanzhong dairy goats (44.

The land of homesickness: The impact of homesteads on the social integration of rural migrants.

Promoting the social integration of rural migrants is key to improving the mechanism of rural-urban integration and development. This study utilizes the 2017 China Migrants Dynamic Survey and matched urban macro data to systematically explore the impact of homesteads on the social integration of rural migrants. Research has shown that social integration of rural migrants will be inhibited if they own homesteads.

Joint equalization and decoding with per-survivor processing based on super-trellis in time-varying underwater acoustic channels.

This Letter proposes a low-complexity joint equalization and decoding reception scheme based on super-trellis per-survivor processing, making it possible to apply maximum likelihood sequence estimation in high-order underwater acoustic communications under fast time-varying channels. The technique combines trellis-coded modulation states and intersymbol interference states and uses per-survivor processing to track channel parameters. Furthermore, a general trellis configuration for arbitrary order quadrature amplitude modulation signal is provided when truncate the channel is used to describe the intersymbol interference state to 1.

Comments on "Planar Tetracoordinate Hydrogen: Pushing the Limit of Multicentre Bonding".

In a recent communication (Angew. Chem. Int.

Tetracoordinate or tricoordinate? Planar tetracoordinate nitrogen in the NBe4H4- cluster stabilized by multicenter bonds.

Realization of planar tetracoordinate arrangements of nitrogen atoms is challenging because their preference for localized bonding (caused by its high electronegativity) makes them typically tricoordinate. This is especially true for the more electronegative oxygen atoms. Herein, we computationally designed two clusters NBe4H4- and OBe4H4; they contain a planar tetracoordinate nitrogen (ptN) and planar tetracoordinate oxygen (ptO) atom, respectively.

CBeH: a molecular rotor with a built-in on-off switch.

It is highly challenging to control (stop and resume as needed) molecular rotors because their intramolecular rotations are electronically enabled by delocalized σ bonding, and the desired control needs to be able to destroy and restore such σ bonding, which usually means difficult chemical manipulation (substitution or doping atom). In this work, we report CBeH, a molecular rotor that can be controlled independently of chemical manipulation. This molecule exhibited the uninterrupted free rotation of Be and H atoms around the central carbon in first-principles molecular dynamics simulations at high temperatures (600 and 1000 K), but the rotation cannot be witnessed in the simulation at room temperature (298 K).

CBSe: a planar tetracoordinate carbon CB core stabilized by peripheral Se/Se bridges.

Replacing one of the peripheral Se with a Se bridge is an effective strategy to flatten the CBSe cluster. The global minimum of CB4Se contains one fan-shaped planar tetracoordinate carbon (ptC) CB core, possessing double 2π + 6σ aromaticity. The peripheral Se bridge is dexterous and crucial for the stability of CBSe.

[(OB)-M©BO-BO] (M = Mn, Tc, Re): Chemically Stable and Triply Aromatic Ballet Rotors.

Single-molecule nanorotors are generally constructed based on boron atoms to obtain structural fluxionality via possessing the delocalized multicenter bonds. However, the electron-deficient boron atoms are commonly exposed in these nanorotors, which leads to extremely high chemical reactivity, which blocks the synthesis in the condensed phase. In this work, we computationally designed a series of transition-metal-doped boron oxide clusters MBO (in structural configuration of [(OB)-M©BO-BO], M = Mn, Tc, Re, © means "centered" in a planar or quasi-planar hypercoordinate environment), which can be vividly named as "ballet rotors" to label their anthropomorphic dynamic rotational behaviors.

Dynamic evolution and impact mechanism of human capital mismatch in strategic emerging industries: Evidence from the Yangtze River Delta region of China.

China's "demographic dividend" has gradually disappeared since 2013, but the problem of human capital mismatch prevails in various industries and sectors, and improving human capital mismatch and optimizing the allocation of human capital has become an important measure for high-quality economic development. This study uses panel data at the provincial level in the Yangtze River Delta region from 2012 to 2021 and employs spatial econometric models to quantitatively analyze the index of human capital mismatch, the impact mechanism, and spatial interaction effects in strategic emerging industries. The results show that the spatial agglomeration and dependence of human capital mismatch decreased in the Yangtze River Delta region, and the index of human capital mismatch in strategic emerging industries is generally insufficient.

Expectation-maximization vector approximate message passing-based frequency-domain turbo equalization for underwater acoustic communications.

Channel equalization plays a crucial role in single-carrier underwater acoustic (UWA) communications. Recently, a frequency-domain turbo equalization (FDTE) scheme enabled by the vector approximate message passing (VAMP) algorithm, was proposed, and it outperformed classic linear minimum mean square error FDTE at acceptable complexity cost. The operation of the VAMP-FDTE requires knowledge of noise power, which is predetermined before the equalization starts.

Rumen bacterial cluster identification and its influence on rumen metabolites and growth performance of young goats.

Enterotypes, which are defined as bacterial clusters in the gut microbiome, have been found to have a close relationship to host metabolism and health. However, this concept has never been used in the rumen, and little is known about the complex biological relationships between ruminants and their rumen bacterial clusters. In this study, we used young goats ( = 99) as a model, fed them the same diet, and analyzed their rumen microbiome and corresponding bacterial clusters.

Planar Hexacoordinate Beryllium: Covalent Bonding Between s-block Metals.

Achieving a planar hypercoordinate arrangement of s-block metals through covalent bonding with ligands is challenging due to the strong ionicity involved. Herein, we report the first case of a neutral binary global minimum containing a planar hexacoordinate beryllium atom. The central Be atom is coordinated by six active Be atoms, the latter in turn are enclosed by an equal number of more electronegative chlorine atoms in the periphery, forming a star-like phBe cluster (Be©Be Cl ).

[Cs©C] and [Na©C]: perfect planar alkaline-metal-centered polyynic cyclo[]carbon complexes with record coordination numbers.

Searching for the maximum coordination number (CN) in planar species with novel bonding patterns has fascinated chemists for many years. Using the experimentally observed polyynic cyclo[18]carbon C and theoretically predicted polyynic cyclo[14]carbon C as effective ligands and based on extensive first-principles theory calculations, we predict herein their perfect planar alkaline-metal-centered complexes Cs©C (1) and Na©C (4) which as the global minima of the systems possess the record coordination numbers of CN = 18 and 14 in planar polyynic species, respectively. More interestingly, detailed energy decomposition and adaptive natural density partitioning bonding analyses indicate that the hypercoordinate alkaline-metal centers in these complexes exhibit obvious transition metal behaviors, with effective in-plane (π-6s)σ, (π-7p)σ, and (π-5d)σ coordination bonds formed in Cs©C (1) and (π-3s)σ, (π-3p)σ, and (π-3d)σ coordination interactions fabricated in Na©C (4) to dominate the overall attractive interactions between the metal center and its cyclo[]carbon ligand.

Probabilistic constellation shaping-aided underwater acoustic communication with vector approximate message passing iterative equalization.

A probabilistic constellation shaping (PCS)-aided single-carrier transceiver is proposed to improve spectral efficiency for underwater acoustic (UWA) communications. At the transmitter, the information bits are input into a distribution matcher followed by a systematic binary encoder, which yields a sequence of sign bits with a uniform distribution and a sequence of amplitude bits with a non-uniform distribution. Based on these two sequences, the PCS is then realized by mapping coded bits onto a quadrature amplitude modulation constellation.

How hexafluoroisopropanol solvent promotes Diels-Alder cycloadditions: metadynamics simulations.

The solvent effects in Diels-Alder cycloadditions were studied by using molecular dynamics simulations with explicit molecular treatments for both substrates and solvents. Energy decomposition analysis was used to investigate the role of H-bonding networks of hexafluoroisopropanol solvent in promoting both reactivity and regioselectivity.

Rapid Adaptation for Active Pantograph Control in High-Speed Railway via Deep Meta Reinforcement Learning.

Active pantograph control is the most promising technique for reducing contact force (CF) fluctuation and improving the train's current collection quality. Existing solutions, however, suffer from two significant limitations: 1) they are incapable of dealing with the various pantograph types, catenary line operating conditions, changing operating speeds, and contingencies well and 2) it is challenging to implement in practical systems due to the lack of rapid adaptability to a new pantograph-catenary system (PCS) operating conditions and environmental disturbances. In this work, we alleviate these problems by developing a revolutionary context-based deep meta-reinforcement learning (CB-DMRL) algorithm.

NAlX (X = S, Se, Te): Clusters with a planar tetracoordinate nitrogen and significantly improved stability.

The design of clusters featuring non-classical planar hypercoordinate atoms (phAs) often depends on the delocalized multicenter bonds involving reactive electron-deficient elements, which both destabilize the clusters and lead to difficulty in achieving the phA arrangement for electronegative elements such as nitrogen due to their preference for localized bonds. In this work, we computationally designed a series of aluminum chalcogenide clusters NAlX (X = S, Se, Te) with a desired planar tetracoordinate nitrogen and meaningfully improved chemical stability, as evidenced by the wide gaps (6.51-7.

3-D molecular stars with covalent axial bonding.

In designing three-dimensional (3-D) molecular stars, it is very difficult to enhance the molecular rigidity through forming the covalent bonds between the axial and equatorial groups because corresponding axial groups will generally break the delocalized π bond over equatorial frameworks and thus break their star-like arrangement. In this work, exemplified by designing the 3-D stars Be ©Be E (E = Au, Cl, Br, I) with three delocalized σ bonds and delocalized π bond over the central Be ©Be moiety, we propose that the desired covalent bonding can be achieved by forming the delocalized σ bond(s) and delocalized π bond(s) simultaneously between the axial groups and equatorial framework. The covalency and rigidity of axial bonding can be demonstrated by the total Wiberg bond indices of 1.

Prediction of heptagonal bipyramidal nonacoordination in highly viable [OB-M©BO-BO] (M = Fe, Ru, Os) complexes.

Non-spherical distributions of ligand atoms in coordination complexes are generally unfavorable due to higher repulsion than for spherical distributions. To the best of our knowledge, non-spherical heptagonal bipyramidal nonacoordination is hitherto unreported, because of extremely high repulsion among seven equatorial ligand atoms. Herein, we report the computational prediction of such nonacoordination, which is constructed by the synergetic coordination of an equatorial hepta-dentate centripetal ligand (BO) and two axial mono-dentate ligands (-BO) in the gear-like mono-anionic complexes [OB-M©BO-BO] (M = Fe, Ru, Os).

Weak Electrostatic Interactions with Bisphosphine Ligands Facilitate Reductive Elimination of PhCF from Pd(II) Complexes.

The origins of ligand effects on PhCF reductive elimination from Pd complexes were computationally investigated by using energy decomposition analysis. The results indicate weak electrostatic interactions between ligands and Ph-Pd-CF lead to small barriers of PhCF reductive elimination. Two major factors affecting the electrostatic interactions are identified.

Ab Initio Metadynamics Simulations of Hexafluoroisopropanol Solvent Effects: Synergistic Role of Solvent H-Bonding Networks and Solvent-Solute C-H/π Interactions.

The solvent effects in Friedel-Crafts cycloalkylation of epoxides and Cope rearrangement of aldimines were investigated by using ab initio molecular dynamics simulations. Explicit molecular treatments were applied for both reactants and solvents. The reaction mechanisms were elucidated via free energy calculations based on metadynamics simulations.

A Reinforcement Learning-Based Pantograph Control Strategy for Improving Current Collection Quality in High-Speed Railways.

In high-speed railways, the pantograph-catenary system (PCS) is a critical subsystem of the train power supply system. In particular, when the double-PCS (DPCS) is in operation, the passing of the leading pantograph (LP) causes the contact force of the trailing pantograph (TP) to fluctuate violently, affecting the power collection quality of the electric multiple units (EMUs). The actively controlled pantograph is the most promising technique for reducing the pantograph-catenary contact force (PCCF) fluctuation and improving the current collection quality.