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Montmorillonite (MMT), as a naturally sourced and FDA-approved biomaterial, has attracted considerable attention due to its extensive application in biomedical areas, such as intestinal ailments, drug delivery, and additive manufacturing. In this work, two-dimensional montmorillonite (2D-MMT) ultrathin nanosheets were successfully prepared from sodium montmorillonite (Na-MMT) by utilizing a freeze-drying assisted method. Possessing a large specific surface area and increased number of exposed hydroxyl groups, 2D-MMT nanosheets exhibited better antibacterial ability than the original Na-MMT. More strikingly, we found that both 2D-MMT nanosheets and Na-MMT could generate reactive oxygen species (ROS) upon visible light illumination, which could promote their antibacterial efficiency. As a result, 2D-MMT nanosheets showed efficient antibacterial performance in the presence of light towards Escherichia coli with a simultaneous enhancement of surface adsorption and photodynamic ablation. What's more, a possible mechanism for ROS generation by MMT upon light illumination was first proposed in this work. The combination of the increased physical adsorption capacity and ROS generation ability of 2D-MMT nanosheets would help inspire the development of MMT as a promising antimicrobial candidate in the future.

Calcium ions (Ca2+) are extremely important for efficiently improving the mechanical properties of alginate dual-crosslinked hydrogels through the synergy of crack bridging of covalent crosslinking and hysteresis of ionic crosslinking, but it is hard to achieve a high content of Ca2+ (>5 wt%) in these hydrogels for the following reasons. The low solubility and poor dispersion of CaSO4 in the gelling solution lead to a low Ca2+ content (

The substitution of noble metal platinum catalyst is one of the important research contents for sustainable development and is also the key to the practical application of photoelectrochemical (PEC) hydrogen production. In this work, we loaded the 1T-2H mixed phase MoS2 on the hydrogenated anatase/rutile heterophase TiO2 (A-H-RTNA) by hydrothermal method to prepare a new MoS2/A-H-RTNA electrode material. The prepared material exhibited higher carrier density, lower PL intensity and higher conductivity than Pt/A-H-RTNA because 1T-MoS2 has more active sites and lower charge transfer resistance than Pt. With the bias voltage of −0.4 V, the optimized 16MoS2/A-H-RTNA as photocathode shows the largest PEC hydrogen production rate of 1840 mmol m−2 h−1, which is 2.9 and 2.2 times higher than those of A-H-RTNA (625 mmol m−2 h−1) and Pt/A-H-RTNA (848 mmol m−2 h−1), respectively. We innovatively used the prepared 16MoS2/A-H-RTNA film as counter electrode instead of Pt electrode to construct a PEC system without any noble-metal. The result demonstrates that the noble-metal-free MoS2 loaded on TiO2 electrode as counter electrode has 75% PEC activity of noble metal Pt electrode. This study develops a PEC method for hydrogen evolution, which no longer depends on precious metal platinum as cathode.

Tree peony (Paeonia section Moutan DC.) has recently been recognised as an important woody oil plant of high economic value, with its seeds containing high levels of α-linolenic acids (ALA,...

Tree peony has been widely planted as an excellent oil crop with high proportion of α-linolenic acid (ALA) in its seeds. It was reported that pollen sources have clear effects on fatty acid (FA) composition of its kernels. Nevertheless, the molecular basis of this novel phenomenon is poorly understood. In this study, four Paeonia suffruticosa cultivars whose pollen caused significant differences in ALA content of Paeonia rockii were selected as pollen donors and grouped under high and low ALA groups. After pollination, total FAs content, composition and expression profiles of 10 genes involved in the FA and triacylglycerol (TAG) biosynthetic pathways were investigated during seed development. During the rapid oil accumulation in seeds, three desaturase genes (SAD, FAD2, FAD3) showed much higher expression in high ALA group, and their differential expression profiles corresponded well with the variations in ALA content among different pollen sources. Overall, pollen sources could affect the expression level of genes associated with fatty acid modification and subsequently affect the composition of FA in the kernels.

Let p be a prime with $p\equiv1\bmod8$ , ψ be an eighth character modp, and $\tau(\psi)$ denote the classical Gauss sum modp. The main purpose of this paper is using the analytic method and the properties of the classical Gauss sum to study the computational problem of one kind rational polynomial of $\tau(\psi)$ . In the end, we prove an interesting second-order linear recursive formula for it.

In this paper, we propose a 3D object pose estimation method based on the frustum point cloud for industrial picking robot to grab the express. The core of our idea is to segment the point cloud of the object which should to be pick up first, then extract the best grab plane and grab point on the object point cloud. First of all, a mature 2D detection framework Faster RCNN is used to detect the object in RGB images. Then the 2D bounding box and category of the object closest to the camera will be output. On the basis of this, the frustum point cloud data of the detected object is generated by the combination of the depth map and the projection relationship of the RGB-D camera. Then we used PointNet network to extract the feature of each point in the generated frustum point cloud. Finally, the instance segmentation of the point cloud and the subsequent extraction of the best grab plane and grab point are performed. We show results on both real dataset and synthetic dataset which we collected by ourselves, and our 3D instance segmentation network accuracy on real dataset reached 88%.

In the past few years, anatase/rutile TiO2 heterophase junction structures with highly efficient photocatalytic performance have been explored widely, while their activities are still unsatisfactory in solar-to-hydrogen energy conversion. In this study, a novel anatase/rutile TiO2 photoelectrode with hydrogenated heterophase interface structures (A-H-RTNA) was successfully designed and synthesized for the first time via hydrothermal synthesis–hydrogenation–branching growth. Structure characterization indicated that the hydrogenated interfaces between anatase–branches and rutile–TiO2–nanorod hold appropriate oxygen vacancies and Ti3+ and inferred that new energy levels of oxygen vacancy and Ti–OH lie below the band edge positions of conduction band and valence band of rutile TiO2 nanorod, respectively. The matching energy levels between anatase–branches and hydrogenated rutile–nanorod obviously reduce the recombination of the photogenerated carriers, resulting in a superior photoelectrochemical (PEC) perfo...

We used the algebraic manipulations and the properties of Chebyshev polynomials to obtain an interesting identity involving the power sums of the integral of the first-kind Chebyshev polynomials and solved an open problem proposed by Wenpeng Zhang and Tingting Wang.

The main purpose of this paper is using the analytic methods and a relation between the two-term cubic exponential sums and general Kloosterman sums to study the computational problem of one kind high-th power mean of general Kloosterman sums for some special non-principal character $$\chi \bmod p$$ , and give four exact computational formulae for them. As applications of these results, we obtained four interesting asymptotic formulae for the 6th, 8th, 10th and 12th power mean of general Kloosterman sums with a special character $$\chi \bmod p$$ .

Two kinds of branched TiO 2 nanorods arrays (TNRs), i.e. rutile nanorod covered with rutile branches (BTNRs) and rutile nanorod covered with anatase branches (ATNRs), were synthesized on FTO films as photoanodes. Photoelectrochemical (PEC) performances of the both photoanodes were comparably evaluated. The PEC hydrogen production rate of ATNRs photoanode is 4.2 and 2.7 times those of the TNRs and BTNRs photoanodes, respectively. The ATNRs showed a highly PEC response because of a lower intrinsic resistance and a heterophase structure between rutile nanorod and anatase branches. The study explicitly ascertains a kind of more effective structure for photoelectrical materials and gives new insight into intrinsic resistance based on PEC analyses.

Purpose The purpose of this paper was to study the corrosion control of B10 copper-nickel alloy using the LiOH-N2H4 compound inhibitors and to evaluate the feasibility of replacing the original inhibitors (NaNO2-Na2MoO4) with the new ones (LiOH-N2H4) for the chilled water system in a nuclear unit. Design/methodology/approach The corrosion resistance performance of B10 copper-nickel alloy was evaluated during the whole replacement process of inhibiters using electrochemical tests and surface analysis techniques. Findings The results indicated that the corrosion of B10 copper-nickel alloy could be prevented effectively using LiOH to increase the pH value of solution higher than 10.0 and using N2H4 to consume dissolved oxygen. During the replacement process of inhibitors from NaNO2-Na2MoO4 to LiOH-N2H4, the corrosion resistance performance of B10 copper-nickel alloy had not decreased greatly. The new LiOH-N2H4 inhibitor, which could enhance the compactness of rust, was able to reduce the corrosion rate of rusted B10 metal. Originality/value It is feasible and operable to replace the NaNO2-Na2MoO4 inhibitors with the LiOH-N2H4 inhibitors for the corrosion prevention of B10 copper-nickel alloy. The research results can provide guidelines for the inhibitor selection of chilled water system in a nuclear unit.

In this paper, wavelet transform profilometry (WTP) method is studied to achieve a train wheel surface 3-D topography reconstruction and defects inspection. A structured light illumination is used to generate periodic fringes, and a CCD camera is used to capture the image of deformed fringes caused by a 3-D topography. The Complex Morlet wavelet is used to transform the deformed fringes image. By extracting the maximum value of wavelet transform ridge, distribution of wrapped phase caused by cliffy surface variation is obtained. A reliability algorithm is used for phase unwrapping. Simulation is done to manifest the feasibility of the method, and the maximal deviation of a 3-D reconstructed surface is 0.15 mm, so comparing with traditional 3-D reconstruction method, this method achieves a higher accuracy. Validation test on a train wheel shows that this method performs a precise 3-D reconstruction of large dimension object such as wheel surface, while small dimension object such as surface defects is also fine recognized simultaneously. Comparing with light section method, this method achieves a faster 3-D reconstruction.

The phytochemical investigation on the acetone extract of Euphorbia milii afforded thirteen new ent-rosane diterpenoids (1–13) through bioassay guided fractionation for evaluating its effect on Epstein–Barr virus (EBV) DNA lytic replication. Structures were determined by comprehensive spectroscopic analyses including 1D & 2D NMR techniques, chemical methods, and experimental and calculated electronic circular dichroism (ECD) data. The absolute configuration of euphominoid A (1) was established by single crystal X-ray diffraction analysis of its p-bromobenzoate derivative 1a. Compounds 1–3, and 10 displayed inhibitory activity with EC50 values ranging from 5.4 to 29.1 μM and selective index (SI) values varied from 4.5 to 9.3. Compound 2 showed the most potent inhibitory activity with an EC50 value of 5.4 μM comparing with the positive control (+)-rutamarin (EC50 = 5.4 μM). This is the first report of ent-rosane-type diterpenoids exhibiting significant inhibition of EBV lytic replication.

(+)-Rutamarin inhibits EBV lytic DNA replication with an IC50 of 7.0 μM. (−)-Chalepin, a (−)-rutamarin derivative, was isolated from the whole plant of Ruta graveolens and used as a precursor of (−)-rutamarin. Altogether, 28 (−)-rutamarin derivatives were synthesized starting from (−)-chalepin. Of these, 16 compounds (2a–e, 3b–e, 3g, 4f, 4k, 4m–p) were found to be more potent against EBV lytic DNA replication than (−)-chalepin. Compounds 4m, 4n, and 4p exhibited IC50 values of 1.5, 0.32, and 0.83 μM and showed selectivity index values (SI) of 801, 211, and >120, respectively. Thus, compounds 4m, 4n, and 4p are considered promising leads for further laboratory investigation.

Tree peony is a perennial deciduous shrub with great ornamental and medicinal value. A limitation of its current functional genomic research is the lack of effective molecular genetic tools. Here, the first application of a Tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) in the tree peony species Paeonia ostii is presented. Two different approaches, leaf syringe-infiltration and seedling vacuum-infiltration, were utilized for Agrobacterium-mediated inoculation. The vacuum-infiltration was shown to result in a more complete Agrobacterium penetration than syringe-infiltration, and thereby determined as an appropriate inoculation method. The silencing of reporter gene PoPDS encoding phytoene desaturase was achieved in TRV-PoPDS-infected triennial tree peony plantlets, with a typical photobleaching phenotype shown in uppermost newly-sprouted leaves. The endogenous PoPDS transcripts were remarkably down-regulated in VIGS photobleached leaves. Moreover, the green fluorescent protein (GFP) fluorescence was detected in leaves and roots of plants inoculated with TRV-GFP, suggesting the capability of TRV to silence genes in various tissues. Taken together, the data demonstrated that the TRV-based VIGS technique could be adapted for high-throughput functional characterization of genes in tree peony.