Comparative pharmacokinetic study of four major bioactive components after oral administration of Zhi‐Zi‐Hou‐Po decoction in normal and corticosterone‐induced depressive rats

A highly selective and efficient LC–MS/MS method was developed to determine the plasma concentration of magnolol, hesperidin, neohesperidin and geniposide following oral administration of Zhi‐Zi‐Hou‐Po decoction in normal and depressed rats. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an XTerra^® MS C₁₈ column using a gradient elution with a mobile phase composed of acetonitrile–0.1% aqueous formic acid. The proposed method was validated to be specific, accurate and precise for the analytes determination in plasma samples. The calibration curves displayed good linearity over definite concentration ranges for the analytes. The intra‐ and inter‐day precision of the proposed method at three different levels were all within <11.13% and the relative errors ranged from ?8.46 to 8.93%. The recovery of the four compounds ranged from 82.72 to 89.08% and no apparent matrix effect was observed during sample analysis. After full validation, the established method was successfully applied for comparing the pharmacokinetics of four components between normal and depressed rats. The results showed that the AUC and C_max of four analytes in depressed rats were significantly different from those in normal rats and might provide helpful information to guide the clinical use of Zhi‐Zi‐Hou‐Po to treat depression.     

Synthetic Humic Acids Solubilize Otherwise Insoluble Phosphates to Improve Soil Fertility

Artificial humic acids (A‐HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the ‐COOH and phenolic groups of humic acids, but also illustrated the importance of the redox properties of humic matter on the nanoscale. The combined effects result in the formation of then bioavailable phosphate nanoparticles stabilized by humic matter. Typical agricultural chemical tests indicate that the content of total P and directly plant‐available P improved largely. Comparative pot planting experiments before and after treatment of phosphates with A‐HA demonstrate significantly enhanced plant growth, as quantified in higher aboveground and belowground plant biomass.     

A stable pillared metal–organic framework constructed by H4TCPP ligand as luminescent sensor for selective detection of TNP and Fe3+ ions

A novel luminescent metal–organic framework ( Zn‐TCPP/BPY ) with pillared structure based on 2,3,5,6‐tetrakis(4‐carboxyphenyl)pyrazine (H₄TCPP) and 4,4′‐bipyridine (BPY) has been designed and synthesized through a solvothermal reaction. The [Zn₂(COO)₄] paddlewheel units are linked by TCPP^4? ligands to form two‐dimensional layers and further connected by BPY ligands as pillars to construct the twofold interpenetrating three‐dimensional framework. Interestingly, Zn‐TCPP/BPY possesses outstanding stability in organic solvents and water as well as maintains its structural rigidity in aqueous solutions of different pH values (3–12). After activation, Zn‐TCPP/BPY possesses permanent porosity with Brunauer–Emmett–Teller surface area of 630 m² g^–1. Remarkably, Zn‐TCPP/BPY displays excellent fluorescent property in virtue of the aggregation‐induced emission effect of the H₄TCPP ligand, which can be highly active and quenched by small amounts of 2,4,6‐trinitrophenol (TNP) and Fe³⁺ ions. Furthermore, the detection effect of Zn‐TCPP/BPY remains basically the same even after five cycles. The excellent stability, high sensitivity, and recyclability of Zn‐TCPP/BPY make it an outstanding chemical sensor for detecting TNP and Fe³⁺ ions.     

Lone-Pair Enhanced Birefringence in an Alkaline-Earth Metal Tin(II) Phosphate BaSn2(PO4)2

The first alkaline-earth metal tin(II) phosphate, BaSn₂(PO₄)₂, has been discovered, which consists of layered structures constructed from strictly alternating [SnO₃]⁴⁻ and [PO₄]³⁻ moieties. This compound is expected to have a large birefringence with Δn≈0.071 at 1064 nm, owing to the presence of stereochemically active lone pair metal cations.     

Finite-time boundedness of uncertain Hamiltonian systems via sliding mode control approach

Nonlinear Dynamics - This paper seeks to address the problem of finite-time stabilization for a class of uncertain Hamiltonian systems via sliding mode control approach. A novel sliding function in...     

BiVO4/TiO2 heterojunction with rich oxygen vacancies for enhanced electrocatalytic nitrogen reduction reaction

The large-scale production of ammonia mainly depends on the Haber–Bosch process, which will lead to the problems of high energy consumption and carbon dioxide emission. Electrochemical nitrogen fixation is considered to be an environmental friendly and sustainable process, but its efficiency largely depends on the activity and stability of the catalyst. Therefore, it is imperative to develop highefficient electrocatalysts in the field of nitrogen reduction reaction (NRR). In this paper, we developed a BiVO₄/TiO₂ nanotube (BiVO₄/TNT) heterojunction composite with rich oxygen vacancies as an electrocatalytic NRR catalyst. The heterojunction interface and oxygen vacancy of BiVO₄/TNT can be the active site of N₂ dynamic activation and proton transition. The synergistic effect of TiO₂ and BiVO₄ shortens the proton transport path and reduces the over potential of chemical reaction. BiVO₄/TNT has high ammonia yield of 8.54 μg·h⁻¹·cm⁻² and high Faraday efficiency of 7.70% in −0.8 V vs. RHE in 0.1 M Na₂SO₄ solution.     

Rate sensitivity and deformation mechanism of semi-crystalline polymers during instrumented indentation

Instrumented indentation tests using both constant loading rate (CLR) and continuous stiffness measurement (CSM) operation modes were performed to investigate the deformation mechanism and their sensitivity to the deformation rate in semi-crystalline polymers through the quantitative analysis of load-depth loading and unloading curves. The strain rate was constant during the CSM tests, while the strain rate decreased with the increasing of loading time in CLR tests. The mechanical response mechanism of the semi-crystalline polymers to these tests was very complicated because of the combined effects of strain-hardening in the crystal phase and strain-softening in the amorphous phase. Results show that the loading index m reflects the strain-hardening or strain-softening response during indentation. When m > 2, the mechanical response was due to the strain-hardening, and when m < 2, the response was due to strain-softening. A method based on the measured contact hardness was proposed to obtain the unloading stiffness, and the other mechanical parameters could then be determined according to the unloading stiffness.     

Electrodeposited molybdenum-doped Co3O4 nanosheet arrays for high-performance and stable hybrid supercapacitors

Journal of Solid State Electrochemistry - Long-cycle stability and high-energy density are big challenges for developing high-performance hybrid supercapacitor (HSC) electrode materials. In this...     

Metal–Organic Framework (MOF)-Derived Carbon-Mediated Interfacial Reaction for the Synthesis of CeO2−MnO2 Catalysts

CeO₂-based catalysts are widely studied in catalysis fields. Developing one novel synthetic approach to increase the intimate contact between CeO₂ and secondary species is of particular importance for enhancing catalytic activities. Herein, an interfacial reaction between metal–organic framework (MOF)-derived carbon and KMnO₄ to synthesize CeO₂−MnO₂, in which carbon is derived from the pyrolysis of Ce-MOFs under an inert atmosphere, is described. The MOF-derived carbon is found to restrain the growth of CeO₂ crystallites under a high calcination temperature and, more importantly, intimate contact within CeO₂/C is conveyed to CeO₂/MnO₂ after the interfacial reaction; this is responsible for the high catalytic activity of CeO₂−MnO₂ towards CO oxidation.     

Entropic effect implication for change in polymer coils swelling state in the demixing enthalpy recovery of aqueous poly(vinyl methyl ether) solutions

Time‐dependent demixing enthalpy recovery behavior of aqueous poly(vinyl methyl ether) (PVME) solutions exhibits distinct recovery characteristics in three concentration regions. The absence of recovery behavior below a water concentration of 38.3 wt % indicates that the PVME coil is in a globular state. The typically sigmoidal recovery behavior of demixing enthalpy above 38.3 wt % is ascribed to the reswelling of the collapsed polymer coils induced by the entropic effect. The increase in difference between the upper and lower limits indicates the continued swelling of the PVME coils. Above 65 wt %, a dominant diluting effect can be observed, and a much longer phase separation time is needed to reach the expected lower limit. In contrast, the recovery of demixing enthalpy in a wide range of water concentration (from 38.3 to 90 wt %) exhibits the same feature. The infrared spectroscopy results are in agreement with the above macroscopic differential scanning calorimetry results. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 142–151