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Multiple phenolic compounds in the extract of Erigeron breviscapus synergistically contribute to the neurovascular protective effects. We conducted a phase I and pharmacokinetic study with the phenolic compound-enriched product extracted from Erigeron breviscapus, Erigerontis hydroxybenzenes injection (EHI), in healthy Chinese volunteers. A randomized, open-label, single-center, double-arm, dose-escalation study of EHI was conducted. The tolerability of intravenously EHI administrated in single- or multiple-dose (once daily for 7 days) was studied in 40 healthy Chinese volunteers and the pharmacokinetics of EHI was studied in additional 10 volunteers. The tolerated dose of intravenous infusion of EHI in healthy Chinese volunteers was 6 vials (equivalent to 90 mg bioactive phenolic compounds). The main limitations to dose escalation of EHI were transit changes in electrocardiogram and mild, transit increase in alanine aminotransferase. After intravenous administration of EHI, the average systemic clearance of multiple phenolic compounds of scutellarin, 1,3-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, and 3,4-dicaffeoylquinic acid were 131, 29, 262, 112 L/h for male volunteers and 202, 28, 252, 117 L/h for female volunteers. The intervention of intravenous infusion of EHI in healthy Chinese volunteers was generally tolerated. The findings from this study provide data on the tolerability and pharmacokinetics of the extract from Erigeron breviscapus and support further trials. [ABSTRACT FROM AUTHOR]

Density functional theory calculations have been performed to explore the potential energy surfaces of CO bond activation in CO2 molecule by gas‐phase Nb atom and Nb+ cation for better understanding the reaction mechanism of second‐row metal with CO2. The minimum‐energy reaction path is found to involve the spin inversion in the different reaction steps. This potential energy curve‐crossing dramatically affects the reaction energetic. The present results show that the mechanism is insertion‐elimination mechanism along the CO bond activation reaction. All theoretical results not only support the existing conclusions inferred from early experiment but also complement the pathway and mechanism for this reaction. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Solid complexes of lanthanide nitrates with an novel unsymmetrical tripodal ligand, butyl- N, N-bis[(2′-benzylaminofomyl)phenoxyl)ethyl]-amine () have been synthesized and characterized by elemental analysis, infrared spectra and molar conductivity measurements. At the same time, the luminescent properties of the Sm(III), Eu(III), Tb(III) and Dy(III) nitrate complexes in solid state were also investigated. Under the excitation of UV light, these complexes exhibited characteristic emission of central metal ions. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The potential energy surfaces for the La+SCO and La++ SCO reactions have been theoretically investigated by using the DFT (B3LYP/ECP/6-311+G(2 d)) level of theory. Both ground and excited state potential energy surfaces (PES) are discussed. The present results show that the reaction mechanism is insertion mechanism both along the C-S and C-O bond activation branches, but the C-S bond activation is much more favorable in energy than the C-O bond activation. The reaction of La atom with SCO was shown to occur preferentially on the ground state (doublet) PES throughout the reaction process, and the experimentally observed species, have been explained according to the mechanisms revealed in this work. While for the reaction between La+ cation with SCO, it involves potential energy curve-crossing which dramatically affects reaction mechanism, and the crossing points (CPs) have been localized by the approach suggested by Yoshizawa et al. Due to the intersystem crossing existing in the reaction process of La+ with SCO, the products SLa+(η2CO) and OLa+(η2CS) may not form. This mechanism is different from that of La + SCO system. All our theoretical results not only support the existing conclusions inferred from early experiment, but also complement the pathway and mechanism for this reaction. [ABSTRACT FROM AUTHOR]

Atomic and electronic structures of liquid and amorphous Ni81B19 and Ni80P20 alloys were simulated by ab initio molecular dynamics. Pair correlation function, bond pair analysis, electronic population analysis, and density of states were calculated. It was found that amorphous Ni81B19 and Ni80P20 alloys can be prepared by rapid quenching, and their structures are similar to those of liquid alloys. Bond pair analysis indicated that the environment of each atom in Ni81B19 system is dominated by icosahedral and distorted icosahedral inherent structures; however, in Ni80P20 system, the tetrahedral order is preponderant. Strong interactions occur between the d-electrons of Ni and the p-electrons of B (or P), which leads to the covalent interactions between Ni and B (or P) atoms. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [ABSTRACT FROM AUTHOR]

To elucidate the mechanism of reaction M+ + SCO, the reaction of Cr+ + SCO has been investigated using density functional theory (DFT) with the popular hybrid functional, B3LYP, in conjunction with 6-311+G* basis set on both the sextet and quartet potential energy surfaces (PESs). To obtain an accurate evaluation of the activation barrier and reaction energy, the coupled cluster single-point calculations using the B3LYP structures is performed. The crossing points (CPs) of the different PESs have been localized with the approach suggested by Yoshizawa and colleagues. The involving potential energy curve-crossing dramatically affects reaction mechanism. The present results show that the reaction mechanism is insertion-elimination mechanism both along the C&bond;S and C&bond;O bond activation branches, but the C&bond;S bond activation is much more favorable than the C&bond;O bond activation in energy. All theoretical results not only support the existing conclusions inferred from early experiment study, but also complement the pathway and mechanism for this reaction. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [ABSTRACT FROM AUTHOR]

AbstractTo address the durability of post-grouted piles in calcareous sand within marine environments, a series of tests including micro-cone penetration, unconfined compressive strength (UCS), scanning electron microscope, energy dispersive spectrometry, and X-ray diffraction was conducted to study the strength changes of cement-stabilized calcareous sand under different curing times and cement ratios. The relationship between UCS and penetration resistance was established and compared with similar tests on cement-stabilized siliceous sand, revealing the micro-erosion mechanisms specific to cement-stabilized calcareous sand. The results show that based on the distribution of penetration resistance, the cement-stabilized soil in a seawater environment can be divided into eroded and non-eroded layers, with erosion depth increasing as curing time extends and cement ratio decreases. After 90 days of curing, the eroded layer exhibited increased porosity, a 34.4% reduction in peak heights of hydration products, and a 16.4% decrease in Ca2+ content compared to the non-eroded layer. These findings highlight that strength changes under seawater erosion result from a balance between enhanced strength due to hydration and weakened strength due to erosion. The study provides insights into evaluating the durability and long-term stability of post-grouted piles in calcareous sand. [ABSTRACT FROM AUTHOR]

AbstractTo elucidate the horizontal bearing mechanism of distributed postside-grouted piles in sandy soil, this study undertakes comparative model tests on ungrouted piles, annular spot-grouted piles, and distributed grouted piles. Additionally, excavation tests and transparent soil experiments are conducted to analyze the diffusion behavior of injected cement grout, thereby illustrating the horizontal bearing mechanism of post-grouted piles. The results show that compared to annular spot-grouting, distributed post-grouting can effectively reform the coefficient of horizontal resistance (m) which recommended range is determined to be 9.0 to 12.7 MN/m4 and enhance the soil strength around the upper part of the pile, improving load transmission and the distribution of bending moments, thereby controlling lateral displacement of the pile shaft and improving the lateral earth resistance on piles. Furthermore, excavation tests and transparent soil experiments demonstrate that grout in sandy soil disseminates through compaction-type diffusion. Notably, distributed grouted piles exhibit more uniform grout coverage, forming a more comprehensive cover layer and exhibiting a more pronounced radial expansion effect. Additionally, the analysis of the horizontal bearing mechanism further confirms the test conclusions, providing theoretical support for the horizontal bearing mechanism of the distributed postside-grouted pile in sandy soil and facilitating practical engineering applications. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the effect of combined end-and-side grouting on the bearing properties of large-diameter rock-socketed bored piles in highly weathered rock layers. Eight full-scale pile load tests were conducted in the highly weathered rock layer to analyze the enhanced mechanism of the combined grouted bored piles. The test data from pile mechanical testing were compared with the recommended values in the current specification and geological survey report. The results demonstrate significant improvement in the side and end resistances of the combined grouted bored piles, resulting in a substantial increase in the bearing capacity and effective settlement control. It was observed that the construction of impact holes for bored piles can cause severe damage to highly weathered rock structures and weaken the mobilization of side and end resistances. Moreover, it was found that the calculation of the enhancement coefficient in the current specification underestimates the practical bearing capacity. The measured enhancement coefficients for the side and end resistance of piles in fully or highly weathered rock layers range from 2.49 to 3.05 and 2.24 to 2.43, respectively, which are more reasonable and feasible for the calculation. The research findings deepen the understanding of the bearing characteristics of large-diameter rock-socketed bored piles with combined grouting and provide valuable case references for the optimal design of large-diameter combined grouted piles for building foundations in Shenzhen, China. Highlights: Post-grouting had the potential to improve super high-building foundation reliability while reducing pile length and cost. The improvement effect and improvement mechanism of combined grouted bored piles embedded in highly rock strata were revealed. The influence of the size effect for large-diameter piles in highly weathered rock was revealed. The construction of impact holes for bored piles can cause severe damage to highly weathered rock structures and weaken the mobilization of side and end resistances. The enhancement coefficients for the side and end resistance of piles in fully or highly weathered rock layers were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-stimuli responsive materials based on triphenylethylene were prepared. • Temperature-triggered photochromism and emission wavelength shift were achieved in T-Br. • Gemini-information output shows great potential for advanced anti-counterfeiting. The development of multi-stimulus responsive materials, especially those capable of displaying multiple patterns within the same region, can significantly enhance information capacity and security. This study presents a novel strategy for gemini-information output activated by temperature and optical stimuli. We synthesized three triphenylethylene derivatives, designated S-Br, D-Br, and T-Br, with aggregation-induced enhanced emission characteristics by varying the number of bromine atom substituents. Notably, thermal activation can induce photochromic behavior of T-Br and achieve wavelength modulation of fluorescence by switching the aggregation state from crystalline to molten amorphous. In contrast, it only enhances the photochromic contrast and fluorescence quenching of S-Br and D-Br. By leveraging their distinct photophysical and photochemical properties, we developed a multi-responsive gemini-encrypted paper. This paper reveals two entirely different information in photochromic and photofluorochromic states when sequentially heated to the melting points of S-Br, D-Br, and T-Br. This gemini-information output triggered by temperature and optical stimuli offers a novel approach to encryption and anti-counterfeiting, and demonstrate enormous potential for enhancing the level of anti-counterfeiting. [ABSTRACT FROM AUTHOR]

An improved advanced oxidation process called MHACF-UiO-66(Zr) was established after the hydrogen and Pd/UiO-66(Zr) was added into the classic Fenton reaction system under normal temperature and pressure. The concentration of ferrous could be maintained more than 12 μM in the initial addition condition of trace level ferrous during the whole reaction process because the regeneration of ferric could be accelerated by the reduction of hydrogen. Through the direct detection and indirect quenching experiment, it could be confirmed that the target pollutant sulfamethazine was efficiently destructed by hydroxyl radical in the MHACF-UiO-66(Zr) system. The degradation pathway of this antibiotic, which was predicated by DFT calculation and further confirmed by the detection of intermediate products, followed by the cleavage of S–N bond. More than 98% of sulfamethazine could be degraded after 180 min reaction process. This removal efficiency was 4.8 times than that of Fenton system. Those parameters, such as the flow of H 2 , initial pH, concentration of sulfamethazine and dosage of Pd/UiO-66(Zr), hydrogen peroxide and ferrous, were systematically studied. Relied on the excellent stability of Pd/UiO-66(Zr) confirmed by morphological characterization, sulfamethazine could be efficiently degraded in this novel reaction system. [Display omitted] ► The novel MHACF-UiO-66(Zr) system was used to degrade sulfamethazine under normal temperature and pressure. ► The introduction of H 2 and Pd/UiO-66(Zr) accelerated the regeneration of FeII. ► Only trace level FeII was required. ► The sulfamethazine could be degraded rapidly by the hydroxyl radical though the cleavage of S–N bond. ► Based on the excellent stability of Pd/UiO-66(Zr), SMT could be efficiently degrade after several consecutive reaction cycles. [ABSTRACT FROM AUTHOR]

The high overpotentials are substantial obstacles for electrocatalytic nitrogen reduction reaction (NRR). The development of non-precious metal electrocatalysts with low overpotentials and high Faradaic efficiencies is crucial for NRR. In this study, we synthesized a series of cobalt-doped WC electrocatalysts by incorporating Co single-atoms into WC lattices. The NRR performance was evaluated using linear sweep voltammetry, cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry in a 0.10 mol/L H 2 SO 4 electrolyte.The results demonstrated that the potential onset for NRR on Co 0.05 W 0.95 C was −0.05 V vs RHE, and the ammonia yield of Co 0.05 W 0.95 C electrocatalyst reached 32.49 ± 0.06 µg·h−1·cm−2 with a Faradaic efficiency of 27.17 ± 0.5 % at a low overpotential of 192 mV under ambient conditions while the performance of the pure cobalt metal is very poor reported by the previous report for NRR. Furthermore,the addition of SCN- ions in the 0.10 mol/L H 2 SO 4 electrolyte reduced the current for NRR.This observation suggests that the Co atoms doped in WC lattices serve as active sites for N 2 reduction. Theory calculations further verified that N 2 molecules were adsorbed on cobalt atoms in Co-doped WC lattices by N 2 -bridge bonds, called enzymatic mechanism, nitrogen molecules were reduced to ammonia following the enzymatic mechanism, which resulted in an extremely low overpotential for NRR. [ABSTRACT FROM AUTHOR]