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Integrating active Pt clusters into transition-metal oxides with water-dissociation ability is effective to prepare a bifunctional electrocatalyst for water splitting in alkaline. However, the additional utilization of a reductant and/or the operation at the elevating temperature causes the over-growth and agglomeration of Pt clusters, thus losing the high catalytic performance. Herein, we report that V dopant not only favors self-reducing Pt clusters on NiFe layered double hydroxide (LDH) (Pt/NiFeV) at room temperature, but also regulates interfacial charge redistribution to enhance the water-splitting performance. Experimental and theoretical studies reveal that V dopant into NiFe LDH triggers more electrons to transfer to adjacent Fe atoms, thus leading to a higher reducing ability compared to that without V-doping. When used as water-splitting electrocatalyst, V doping promotes electron loss of Pt clusters in Pt/NiFeV, optimizing the free energy of hydrogen adsorption and proton recombination kinetics at the cathode. Meanwhile, it also moves the d-band center of Ni away from the Fermi level to optimize the adsorption of *OH intermediates and facilitate the desorption of oxygen molecules at the anode. Thereby, Pt/NiFeV exhibits much higher bifunctional performance than V-free Pt/NiFe LDH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). This work can spark inspiration of designing other bifunctional electrocatalysts for energy conversion and storage.

A nitridation route to synthesize Ru/TiOxNy with fast HER kinetics is successfully developed; this not only optimizes the adsorption energy of hydrogen intermediates, but it also improves electron transfer via forming Ru–N bonds at the interfaces.

This study aims to predict the productivity of an open-hole horizontal gas well (OHHGW) in a gas reservoir with closed bottom and top boundaries (GRCBTBs). First, according to the theory of mirror imaging, an OHHGW in GRCBTBs is transformed into an infinite well array in infinite formation. Second, based on conformal transformation principle, the infinite well array is transformed into two production and two injection wells in the complex plane. Finally, according to the superposition principle of potential, a new productivity prediction method, which is suitable for the horizontal well in GRCBTBs, was developed. The field measured data of Jingbian gas field of Ordos Basin demonstrate the ability of the method to accurately predict the productivity of the OHHGW in GRCBTBs, and the prediction relative error of absolute open flow of well Longping 1 is only 1.03%, that is to say that the method proposed in this study has a certain guiding significance for the development of horizontal wells in GRCBTBs.

Context Total Glucosides of Paeony (TGP) capsule possesses various hepatoprotective activities. No study is available concerning TGP’s concentration–effect relationship on hepatoprotection. Objective To establish a pharmacokinetics–pharmacodynamics (PK-PD) modelling on TGP capsule’s hepatoprotection after a single oral administration in hepatic injury rats. Materials and methods Male Sprague-Dawley rats were divided into five groups (n = 6): control, model (hepatic injury), treated-H (2.82 g/kg), treated-M (1.41 g/kg), and treated-L (0.705 g/kg) groups. All treated groups rats were intragastrically administered a single dose. An LC-MS/MS method was applied to determine paeoniflorin (Pae) and albiflorin (Alb) in rat serum. The effects of single-dose TGP on serum alanine transaminase (ALT), aspartate transaminase (AST) and total bile acid (TBA) were evaluated in hepatic injury rats. Results Single dose (2.82, 1.41, or 0.705 g/kg) TGP capsule could real-time down-regulate serum TBA but not ALT and AST in hepatic injury rats within 20 h. An inhibitory effect Sigmoid Emax of PK-PD modelling was established using Pae and Alb as PK markers and serum TBA as effect index. Pharmacodynamic parameters were calculated. For treated-H, treated-M and treated-L group, respectively, E0 were 158.1, 226.9 and 245.4 μmol/L for Pae, 146.1, 92.9 and 138.4 μmol/L for Alb, Emax were 53.0, 66.0, and 97.1 μmol/L for Pae, 117.4, 249.7 and 60.0 μmol/L for Alb, and EC50 were 9.3, 5.2 and 2.7 μg/mL for Pae, 2.3, 0.8, and 0.8 μg/mL for Alb. Discussion and conclusions Serum TBA is a sensitive effect index for TGP’s single dose PK-PD modelling, and it is potential for further multi-dose studies of TGP’ effect on hepatic injury. The study provides valuable information for TGP’s mechanistic research and rational clinical application.

Based on analysis of NMR T2 spectral characteristics, a new method for identifying fluid properties by decomposing T2 spectrum through signal analysis has been proposed. Because T2 spectrum satisfies lognormal distribution on transverse relaxation time axis, the T2 spectrum can be decomposed into 2 to 5 independent component spectra by fitting the T2 spectrum with Gauss functions. By analyzing the free relaxation response characteristics of crude oil and formation water, the dynamic response characteristics of the core mutual drive between oil and water, the petrophysical significance of each component spectrum is clarified. T2 spectrum can be decomposed into clay bound water component spectrum, capillary bound fluid component spectrum, micropores fluid component spectrum and macropores fluid component spectrum. According to the nature of crude oil in the target area, the distribution range of T2 component spectral peaks of oil-bearing reservoir is 165–500 ms on T2 time axis. This range can be used to accurately identify fluid properties. This method has high adaptability in identifying complex oil and water layers in low porosity and permeability reservoirs.

This study aims to interpret the temperature and pressure behavior of an open-hole horizontal gas well (OHHGW) in a low-permeability gas reservoir in order to obtain the permeability and production profile of the OHHGW. First, the mathematical model, which is comprised of viscous dissipation, friction, the Joule–Thomson effect, and several other micro-thermal effects, was developed under a single-phase condition. Second, during the process of solving the numerical model, the drilling skin, heterogeneity, and non-Darcy effect were taken into consideration. In addition, the reservoir and wellbore models were coupled. Third, the testing temperature and pressure data were inverted using the Levenberg–Marquardt (LM) or Markov Chain simulated annealing algorithms, and the permeability and production profiles of the wellbore were obtained. The synthetic cases demonstrate the models’ ability to predict the temperature profile, and the results show the following: (a) The inversion results are in good agreement with the actual data, that is, the model can provide effective guidance for horizontal well development. (b) The wellbore temperature is lower than that of the reservoir boundary, so the micro-thermal effects for the horizontal gas well cannot be ignored during production. (c) As the gas production, the relative density of the gas, and the drilling skin factor increase, the wellbore temperature profile gradually decreases. The wellbore temperature increases with increasing horizontal permeability. (d) The trend of the temperature profile is contrary to the flow path of the wellbore fluid. (e) Reservoir heterogeneity has a significant influence on the temperature profile.

NiFe layered double hydroxides (LDHs) usually exhibit high water-dissociation ability in the alkaline media and also provide an ideal substrate for anchoring noble metals, such as platinum (Pt), due to the 2D microstructure. Appropriate regulation of the interaction between Pt and substrate could enhance the intrinsic activity of composite catalysts toward the hydrogen evolution reaction (HER) in the alkaline media. Herein, we electrodeposit Pt nanoparticles on amorphous NiFe LDH (Pt/NiFe-ED) or crystalline NiFe LDH (Pt/NiFe-HD) to regulate the interaction between Pt and NiFe LDH. Experimental results reveal that Pt nanoparticles on NiFe-ED are smaller than those on NiFe-HD and possess a narrower size distribution. Thus, Pt/NiFe-ED (300 μM) exhibits a much lower overpotential of 81 mV at 100 mA cm-2 than Pt/NiFe-HD. In contrast, Pt/NiFe-HD exhibits a higher intrinsic activity than Pt/NiFe-ED, which could be caused by the easily elongated Pt-O bond. These findings provide new opportunities to understand the relationship between activity and crystallinity of substrates in the composite electrocatalyst.

Developing biodegradable photothermal agent holds great significance for potential clinical translation of photothermal therapy. In the current study, one-pot hydrothermal synthesis of MoS2 nanoflakes with desirable degradation capability was presented. The participation of poly(acrylic acid) (PAA) in hydrothermal process could not only facilitate the modification of polyethylene glycol (PEG), but also bestow degradability to the prepared MoS2 nanoflakes. Moreover, the PEGylated hybrid nanoflakes (MoS2–PPEG) also exhibited excellent stability in various medium and outstanding photothermal properties. Interestingly, MoS2–PPEG behaved distinctly different degradation rate in diverse condition. The rapid degradation of MoS2–PPEG was observed in neutral pH solution, whereas much slower degradation occurred in an acidic tumor microenvironment. Furthermore, data indicated that the major degradation product of MoS2–PPEG was water-soluble Mo-based ion. Meanwhile, the good in vitro biocompatibility of MoS2–PPEG wa...