Modulating the electronic structure of VS2via Ru decoration for an efficient pH-universal electrocatalytic hydrogen evolution reaction.

High-efficiency water electrolysis over a broad pH range is desirable but challenging. Herein, Ru-decorated VS2 on carbon cloth (Ru-VS2/CC) has been in situ synthesized, which features the regulated electronic structure of VS2 by introducing Ru. It is remarkable that the optimal Ru-VS2/CC displays excellent electrocatalytic hydrogen evolution activity with overpotentials of 89 and 87 mV at -10 mA cm-2 in 0.5 M H2SO4 and 1.0 M KOH, respectively. Theoretical calculations and electrocatalytic measurements have demonstrated that introducing Ru induces an enhanced charge density around the Fermi level, facilitating charge transfer and speeding up the electrocatalytic HER kinetics. The Gibbs free energy of the hydrogen intermediate (ΔGH*) of Ru-VS2/CC (0.23 eV) is much closer to zero than that of pure VS2 (0.51 eV) and Ru (-0.37 eV), demonstrating an easier hydrogen adsorption and desorption process for Ru-VS2/CC. The more favorable ΔGH*, differential charge density and the d-band center endow Ru-VS2 with enhanced intrinsic electrocatalytic activity. This study presents a feasible strategy for enhancing electrocatalytic HER activity by the regulation of the electronic structure and the rational integration of dual active components.

Hierarchical antibiotic delivery system based on calcium phosphate cement/montmorillonite-gentamicin sulfate with drug release pathways.

Antibiotic-loaded calcium phosphate cement (CPC) has emerged as a promising biomaterial for drug delivery in orthopedics. However, there are problems such as the burst release of antibiotics, low cumulative release ratio, inappropriate release cycle, inferior mechanical strength, and poor anti-collapse properties. In this research, montmorillonite-gentamicin (MMT-GS) was fabricated by solution intercalation method and served as the drug release pathways in CPC to avoid burst release of GS, achieving promoted cumulative release ratios and a release cycle matched the time of inflammatory response. The results indicated that the highest cumulative release ratio and release concentration of GS in CPC/MMT-GS was 94.1 ± 2.8 % and 1183.05 µg/mL, and the release cycle was up to 504 h. In addition, the hierarchical GS delivery system was divided into three stages, and the kinetics followed the Korsmeyer-Peppas model, the zero-order model, and the diffusion-dissolution model, respectively. Meanwhile, the compressive strength of CPC/MMT-GS was up to 51.33 ± 3.62 MPa. Antibacterial results demonstrated that CPC/MMT-GS exhibited excellent in vitro long-lasting antibacterial properties to E. coli and S. aureus. Furthermore, CPC/MMT-GS promoted osteoblast proliferation and exhibited excellent in vivo histocompatibility. Therefore, CPC/MMT-GS has favorable application prospects in the treatment of bone defects with bacterial infections and inflammatory reactions.

Interfacial Interaction in NiFe LDH/NiS2/VS2 for Enhanced Electrocatalytic Water Splitting.

A bifunctional electrocatalyst with high efficiency and low costs for overall water splitting is critical to achieving a green hydrogen economy and coping with the energy crisis. However, developing robust electrocatalysts still faces huge challenges, owing to unsatisfactory electron transfer and inherent activity. Herein, NiFe LDH/NiS2/VS2 heterojunctions have been designed as freestanding bifunctional electrocatalysts to split water, exhibiting enhanced electron transfer and abundant catalytic sites. The optimum NiFe LDH/NiS2/VS2 electrocatalyst exhibits a small overpotential of 380 mV at 10 mA cm-2 for overall water splitting and superior electrocatalytic performance in both hydrogen and oxygen evolution reactions (HER/OER). Specifically, the electrocatalyst requires overpotentials of 76 and 286 mV at 10 mA cm-2 for HER and OER, respectively, in alkaline electrolytes, which originate from the synergistic interaction among the facilitated electron transfer and increasingly exposed active sites due to the modulation of interfaces and construction of heterojunctions.

Interface engineering of 0D/2D Cu2O/BiOBr Z-scheme heterojunction for efficient degradation of sulfamethoxazole: Mechanism, degradation pathway, and DFT calculation.

Constructed heterojunction has been considered an efficient strategy to enhance the migration and transfer of photoinduced charge carriers. Herein, a Z-scheme Cu2O/BiOBr heterojunction with 0D/2D structure was fabricated by microwave hydrothermal method. It was found that the optimal composites photocatalyst showed excellent activity for sulfamethoxazole (SMZ) illumination, and the removal rate reached 90.7%, which was higher than pristine Cu2O (53.0%) and BiOBr (60.0%). Subsequently, the operational parameters such as catalyst dosage, concentrations of pollutants, and pH of solution were investigated. According to the ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRs), Mott-Schottky curve, and density functional theory (DFT) analysis, the Z-scheme degradation mechanism of Cu2O/BiOBr heterostructure was proposed. Among them, the interface structure of 0-dimensions/2-dimensions (0D/2D) can significantly increase the number of heterojunctions in the composite catalyst, and Z-scheme heterostructures can accelerate the generation and migration of photoinduced charge carriers, which has a facilitation effect on improving the decomposition activity of the photocatalyst. Moreover, three possible pathways for SMZ degradation were inferred. This study provides a promising strategy for constructing novel heterojunctions with high photocatalytic performance.

Preparation and Photoelectric Properties of Pr-Doped p-Cu2O Thin Films Photocatalyst Based on Energy Band Structure Regulation.

A Pr-doped p-Cu2O thin film was prepared on indium tin oxide conductive glass by electrochemical deposition; the effect of Pr doping on the structure, morphology, and physicochemical properties of p-Cu2O was investigated. The results show that with the increase in Pr doping amount, the particle size of p-Cu2O increases, the absorption boundary redshifts, and the band-gap width decreases. Pr doping increases the flat band potential and carrier concentration of p-Cu2O; when the doping amount is 1.2 mM, the carrier concentration reaches 1.14 × 1024 cm-3. Compared with pure p-Cu2O, the charge transfer resistance of Pr-doped p-Cu2O decreases and the photocurrent and open circuit voltage increase, indicating that the carrier transfer rate is accelerated, and the separation efficiency of photogenerated electrons and holes is effectively improved. The result of a norfloxacin photocatalytic degradation experiment showed that the degradation rate of norfloxacin increased from 52.3% to 76.2% and Pr doping effectively improved the photocatalytic performance of p-Cu2O. The main reasons for enhancing the photocatalytic performance are that the band gap of Pr-doped p-Cu2O decreases, the Fermi level of Cu2O is closer to the valence band position, the hole concentration near the valence band, and the oxidation capacity increases, and more h+ oxidize norfloxacin molecules. In addition, the Pr in Pr-Cu2O acts as a conductor to guide electrons on the guide band to the crystal surface, which increases the contact between photogenerated electrons and dissolved oxygen, which is conducive to the formation of the active species ·O2- and can effectively reduce the recombination of photogenerated carriers. In the process of photocatalytic degradation of norfloxacin, the main active species are ·O2-, ·OH, and h+, which play auxiliary roles. TOC tests show that the norfloxacin molecules can be effectively degraded into small molecule organic matter, CO2, and H2O in the presence of Pr-doped p-Cu2O.

Study on the poly(methyl methacrylate-acrylic acid)/calcium phosphate cement composite bound by chelation with enhanced water absorption and biomechanical properties.

Polymethylmethacrylate (PMMA) bone cement has been widely used as a critical material for fixing prostheses and filling bone defects. The shrinkage of PMMA bone cement was addressed by the additives, however, the uneven integral water absorption and expansion performance as well as the deteriorated mechanical properties of the modified bone cement after immersion in phosphate buffered saline (PBS) and simulation body fluid (SBF) affected the long-term stability after implantation. Calcium phosphate cement (CPC) is a biomaterial with promising applications in orthopedics, whose hydration reaction provides an important driving force for the transfer of water. Besides, the mechanical properties of CPC can be enhanced with the curing process. In this study, CPC was utilized to modify the poly(methyl methacrylate-acrylic acid) [P(MMA-AA)] bone cement. The results demonstrated the successful construction of interconnected CPC water delivery networks in the P(MMA-AA)/CPC composite, the water absorption ratio and expansion ratio of the composite were up to 131.18 ± 9.14% and 168.19 ± 5.44%, respectively. Meanwhile, the transformation of CPC water delivery networks into rigid mechanical support networks as well as the chelation interaction between organic-inorganic enhanced the mechanical properties of the composite after immersion, the compressive strength after immersion reached 62.97 ± 0.97 MPa, which was 27.65% higher than that before immersion. The degradation ratio of the composite was up to 13.76 ± 0.23% after 9 days of immersion, which was 16.4% higher than that of CPC. Furthermore, composites exhibited superior biocompatibility as the release of Ca2+. Therefore, P(MMA-AA)/CPC composite serves as a promising medical filling material for clinical use.

Hybrid Nano-Phase Ion/Electron Dual Pathways of Nickel/Cobalt-Boride Cathodes Boosting Intercalation Kinetics for Alkaline Batteries.

Nickel-based hydroxides and their derivatives exhibit relatively low capacities and unsatisfactory durability as cathode materials for rechargeable alkaline batteries. In this work, a hybrid NiCo-B nanosheet cathode, integrating electrolyte ion-shuttling channels and electron-transferring networks into a metal-organic framework (MOF), was devised delicately. In the structure, the hybrid ion/electron dual pathways were constructed by NiCo-MOF frameworks and NiCo-B interpenetration networks. It revealed that nano-phase electron-transferring pathways in the MOF obviously boosted ion intercalation kinetics. The as-obtained hybrid NiCo-B nanosheets as cathode materials exhibited reversible capacity as high as 280 mA h g-1 at a current density of 1 A g-1 and excellent rate capability with a capacity retention of 78% from 1 to 10 A g-1. After 2000 charge/discharge cycles at 4 A g-1, the capacity still remained at 94% of the initial one. A full battery assembled with a hybrid NiCo-B cathode and a Fe2O3 anode showed a high capacity of 250 mA h g-1 and a considerable stability of 89% after 1000 cycles. Ragone plots indicated the highest energy density of 409 W h kg-1 and the lowest power density of 1.5 kW kg-1, outperforming other aqueous batteries. It revealed that a syngenetic structure of ion/electron hybrid dual pathways integrated into an MOF could be a potential strategy to optimize ion intercalation electrode materials for alkaline batteries.

Construction of SrTiO3-BiOCl composite catalyst via facial microwave hydrothermal for highly efficient photocatalytic activity towards organic compounds degradation.

This work mainly focuses on the preparation and performance study of SrTiO3-BiOCl composite photocatalysis. The SrTiO3-BiOCl photocatalysts are prepared via the facial microwave hydrothermal method. XRD, UV-vis DRS, SEM, TEM, XPS, N2 adsorption and desorption isothermal experiment, FT-IR, and PL are applied to characterize the prepared samples. The spherical particles of SrTiO3 grow on the flaky BiOCl, and the crystal size is uniform and evenly disperses on the BiOCl. The catalytic performance of the samples was evaluated over the degradation rates of methylene blue(MB). Typically, the clearance rates of MB reached to 99.65% over SrTiO3-BiOCl-50% under visible light, which was much higher than that of SrTiO3 and BiOCl (55.86%, 79.79%, respectively). The active species capturing experiments and ESR showed that the holes (h+) and ·OH are playing the main roles in the degradation process.

The chromosome-level genome of Akebia trifoliata as an important resource to study plant evolution and environmental adaptation in the Cretaceous.

The environmental adaptation of eudicots is the most reasonable explanation for why they compose the largest clade of modern plants (>70% of angiosperms), which indicates that the basal eudicots would be valuable and helpful to study their survival and ability to thrive throughout evolutionary processes. Here, we detected two whole-genome duplication (WGD) events in the high-quality assembled Akebia trifoliata genome (652.73 Mb) with 24 138 protein-coding genes based on the evidence of intragenomic and intergenomic collinearity, synonymous substitution rate (KS ) values and polyploidization and diploidization traces; these events putatively occurred at 85.15 and 146.43 million years ago (Mya). The integrated analysis of 16 species consisting of eight basal and eight core eudicots further revealed that there was a putative ancient WGD at the early stage of eudicots (temporarily designated θ) at 142.72 Mya, similar to the older WGD of Akebia trifoliata, and a putative core eudicot-specific WGD (temporarily designated ω). Functional enrichment analysis of retained duplicate genes following the θ event is suggestive of adaptation to the extreme environment change in both the carbon dioxide concentration and desiccation around the Jurassic-Cretaceous boundary, while the retained duplicate genes following the ω event is suggestive of adaptation to the extreme droughts, possibly leading to the rapid spread of eudicots in the mid-Cretaceous. Collectively, the A. trifoliata genome experienced two WGD events, and the older event may have occurred at the early stage of eudicots, which likely increased plant environmental adaptability and helped them survive in ancient extreme environments.

Identification and Characterization of NBS Resistance Genes in Akebia trifoliata.

Akebia trifoliata is an important multiuse perennial plant that often suffers attacks from various pathogens due to its long growth cycle, seriously affecting its commercial value. The absence of research on the resistance (R) genes of A. trifoliata has greatly limited progress in the breeding of resistant varieties. Genes encoding proteins containing nucleotide binding sites (NBSs) and C-terminal leucine-rich repeats (LRRs), the largest family of plant resistance (R) genes, are vital for plant disease resistance. A comprehensive genome-wide analysis showed that there were only 73 NBS genes in the A. trifoliata genome, including three main subfamilies (50 coiled coil (CC)-NBS-LRR (CNL), 19 Toll/interleukin-1 receptor (TIR)-NBS-LRR (TNL) and four resistance to powdery mildew8 (RPW8)-NBS-LRR (RNL) genes). Additionally, 64 mapped NBS candidates were unevenly distributed on 14 chromosomes, most of which were assigned to the chromosome ends; 41 of these genes were located in clusters, and the remaining 23 genes were singletons. Both the CNLs and TNLs were further divided into four subgroups, and the CNLs had fewer exons than the TNLs. Structurally, all eight previously reported conserved motifs were identified in the NBS domains, and both their order and their amino acid sequences exhibited high conservation. Evolutionarily, tandem and dispersed duplications were shown to be the two main forces responsible for NBS expansion, producing 33 and 29 genes, respectively. A transcriptome analysis of three fruit tissues at four developmental stages showed that NBS genes were generally expressed at low levels, while a few of these genes showed relatively high expression during later development in rind tissues. Overall, this research is the first to identify and characterize A. trifoliata NBS genes and is valuable for both the development of new resistant cultivars and the study of molecular mechanisms of resistance.

p-Cu2O/n-ZnO heterojunction thin films with enhanced photoelectrochemical properties and photocatalytic activities for norfloxacin.

A two-step electrochemical deposition technique was applied to fabricate p-Cu2O/n-ZnO heterojunction thin films. The influence of the deposition potential upon photoelectric performance of the prepared samples was examined utilizing XRD, XPS, SEM, UV-Vis, and electrochemical tests. The results show that the deposition potential has a substantial influence on the properties of the prepared samples. When the deposition potential is -0.45 V, the peak intensity of the (111) crystal plane of the prepared heterojunction is the highest, the band gap increased, and the morphology changes obviously compared to those of Cu2O. The transient photocurrent value is three times that of pure Cu2O, and the charge transfer resistance significantly reduced. The p-Cu2O/n-ZnO heterojunction has a high carrier concentration. Photocatalytic degradation experiments show that degradation rate of norfloxacin increases by 14.4%-76.6%. The enhanced photocatalytic performance of Cu2O is mainly due to the formation of a high-quality heterojunction and the change in the energy band structure, which promotes the transfer rate of the carrier and the separation of photogenic electron hole pairs, thus effectively improving the catalytic efficiency of photocatalysts. Active species detection experiments reveal that positive hole and superoxide anion radical play leading roles in norfloxacin molecule decomposition. In addition, a possible mechanism for the photocatalytic performance of p-Cu2O enhanced by n-ZnO is proposed according to the analysis of the bandgap of p-Cu2O and n-ZnO, along with the built-in electric field formed in the p-n heterojunction. This study provides an effective and alternative method for removing norfloxacin residues in wastewater.

Preparation and performance of Cu2O/TiO2 nanocomposite thin film and photocatalytic degradation of Rhodamine B.

A constant current electrodeposition approach was employed to prepare Cu2O/TiO2 nanocomposite thin film. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Raman, ultraviolet visible light spectrophotometer (UV-Vis), and photoluminescence (PL) measurements were used to characterize and analyze the thin film microstructure, surface morphology, and photoelectric properties. The effect of annealing treatment on the thin film properties is discussed. The response surface methodology (RSM) was employed to optimize the Rhodamine B (RhB) photocatalytic degradation by thin films, and the quadratic multinomial mathematical model was established. The photocatalytic degradation process of RhB was also studied. The results indicate that the prepared Cu2O thin film was of high purity, with a (111) crystal plane preferred orientation. The average particle diameter was approximately 100-200 nm, and the absorbing boundary was approximately 600 nm. After annealing treatment, the absorbing boundary and open-circuit voltage increased, and Cu2O thin film exhibited an obvious absorbance response in the visible-light range. The established model has better fitness and higher reliability, and the R2 value of established quadratic model is 0.9818. The optimal degradation conditions were obtained by RSM. Under optimum conditions, the RhB degradation rate could reach 98.4% in 3 h and the total organic carbon (TOC) removal rate was 48.2%. Recycling results reveal that RhB degradation rate can still reach 94.5% after eight cycles.

CO2 Laser-assisted Deep Sclerectomy Combined With Phacoemulsification in Patients With Primary Open-angle Glaucoma and Cataract.

PURPOSE: To assess the safety and efficacy of CO2 laser-assisted sclerectomy surgery (CLASS) combined with phacoemulsification in patients with primary open-angle glaucoma (POAG) and visually significant cataracts. MATERIALS AND METHODS: This was a prospective, uncontrolled, interventional case series. Seventeen patients (17 eyes) diagnosed with POAG and cataracts were enrolled starting from November 2015. All subjects underwent CLASS combined with phacoemulsification surgery by the same surgeon. After the surgery, all patients were followed for 12 months. The preoperative to postoperative changes in intraocular pressure (IOP), glaucoma medication requirements, best-corrected visual acuity and adverse events were recorded. RESULTS: The results of 17 eyes of 17 patients were included in the statistical analysis. The baseline mean IOP was 23.94±8.57 mm Hg (mean±SD), and patients used 2.18±0.88 types of antiglaucoma medication. At 12 months postsurgery, the mean IOP was 14.67±2.97 mm Hg, and patients used 0.59±0.87 types of antiglaucoma medication (both P<0.001). The logarithm of the minimal angle of resolution of the best-corrected visual acuity improved from 0.77±0.42 preoperatively to 0.33±0.47 postoperatively (P<0.05). Two patients experienced intraoperative perforation accompanied by iris prolapse. One patient exhibited postoperative choroidal detachment. CONCLUSIONS: CLASS with phacoemulsification may become a safe and effective intervention for patients with POAG and visually significant cataracts.

Preparation and characterization of Cu2O nano-particles and their photocatalytic degradation of fluroxypyr.

Cu2O nano-particles were prepared by the liquid-phase reduction method and the effect of the dispersant was studied. The microstructure, surface morphology and optical properties of Cu2O nano-particles were characterized by X-ray diffractometer, X-ray photoelectron spectroscopy, nitrogen static adsorption, scanning electron microscope, particle size analysis, ultraviolet visible light spectrophotometer and photoluminescence spectrometer. The photocatalytic degradation of fluroxypyr using Cu2O was studied by the response surface methodology, and the quadratic multinomial mathematical model was established. The results indicated that the Cu2O crystal particles prepared using the dispersant of polyvinylpyrrolidone were of high purity with the preferential orientation of (111). The average particle size was 605.4 ± 124.8 nm, the specific surface area was 22.641 m2/g, the band gap was approximately 2.04 eV and the absorption edge was about 650 nm. R2 of the established quadratic model was 0.9973 and had good fitness, indicating that the established model was reliable. The optimal degradation conditions were obtained as follows: the initial concentration of fluroxypyr was 11.17 mg/L, the pH of the solution was 12.0 and the H2O2 concentration was 15 mg/L. The degradation rate of fluroxypyr could reach 83.2% and the relative error was 1.20%. After nine times of recycling, more than 75% of fluroxypyr could be degraded.

Design of Nanoparticle-Based Carriers for Targeted Drug Delivery.

Nanoparticles have shown promise as both drug delivery vehicles and direct antitumor systems, but they must be properly designed in order to maximize efficacy. Computational modeling is often used both to design new nanoparticles and to better understand existing ones. Modeled processes include the release of drugs at the tumor site and the physical interaction between the nanoparticle and cancer cells. In this article, we provide an overview of three different targeted drug delivery methods (passive targeting, active targeting and physical targeting), compare methods of action, advantages, limitations, and the current stage of research. For the most commonly used nanoparticle carriers, fabrication methods are also reviewed. This is followed by a review of computational simulations and models on nanoparticle-based drug delivery.

[Transport kinetics of Pb(II) through bulk liquid membrane using PC-88A as carrier].

The effects of stirring speed, carrier concentration and reaction temperature on the transport of Pb(II) ion through bulk liquid membrane were studied with chloroform as membrane solvent and 2-ethylhexyl phosphonic acid-mono-2-ethylhexylester as carrier. The Pb(II) ions concentrations of feed phase and stripping phase were assayed by atomic absorption spectroscopy. The kinetic parameters, including apparent rate constants of Pb(II) ion extraction and re-extraction reactions, the maximum concentration of Pb(II) ion in the liquid membrane, the time of the maximum value of maximum concentration of Pb(II) ion in the liquid membrane and the maximum entry and exit fluxes of Pb(II) ion through the liquid membrane of the extraction and stripping reactions, were evaluated. The apparent activation energy value is 31.65 kJ x mol(-1) for extraction and 23.11 kJ mol(-1) for stripping. The results indicate that good agreement between experimental data and theoretical predictions could be achieved and the kinetics of Pb(II) transport could be evaluated by two consecutive irreversible pseudo-first order reactions. In this condition the chemical reaction is a procedure of controlled reaction rates.

[Study on chemical constituents from Delphinium honanense var. piliteram].

OBJECTIVE: To study the chemical constituents from Delphinium honanense var. piliteram. METHOD: The constituents were isolated and purified with chromatographic methods, identified by NMR, MS and IR. RESULT: Six compounds were isolated and elucidated as siwanine E (1), isoatisine (2), 12-epi-napelline (3), acontine (4), ajadelphinine (5) and beta-sitosterol (6). CONCLUSION: Compounds 1-6 are all isolated from the plant for the first time.

[A study on preparation and characteristic of RuO2/TiO2 coupled photocatalyst].

RuO2/TiQ2 coupled photocatalyst was prepared by sol-gel-dipping method. Being a model reaction, the photocatalytic degradation of direct fast black G was investigated in RuO2/TiO2 powder suspension irradiated by UV-lamp. The results showed that the addition of RuO2 to TiO2 greatly enhanced its photocatalytic activity, and the optimum dipped content of RuO2 was 0.16%, the optimum value of the calcinations temperature and the addition of RuO2/TiO2 powder were 500 degrees C and 5.00 g x L(-1), respectively. The photocatalytic degradation of direct fast black G was experimentally demonstrated to follow the Langmuir-Hinshelwood kinetic model, and the adsorption constant (14.22 L x mmol(-1)) and the reaction rate constant [4.94 x 10(-3) mmol(L x min)(-1)] were determined, respectively.

[Transfer of Pb(II) through the liquid membrane with alkylphosphonic acid as carrier].

The transfer behavior of Pb(II) through the bulk liquid membrane system of PC-88A-CHCl3 was studied. The study include to analysis the effect of Pb(II) transport rate of the pH values in external aqueous phase, carrier concentration, temperature and external aqueous phase concentration. The results showed that the transport rate of Pb(II) markedly raised with the carrier concentration and temperature. The transfer rate can reach 100% under the condition of pH values 2.8-4.0, carrier concentration 5.00%-7.00% and temperature 289 K-303 K.