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The novel boron nitride coupled Bi-rich Bi4O5Br2 layered microspheres (h-BN/Bi4O5Br2-LMs) were successfully synthesized via a facile ionic liquid-in-water (IL/W) microemulsion-mediated route. The physical, chemical and optical properties of these heterojunction photocatalysts were thoroughly characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectroscopy (DRS). Their photocatalytic activities were primarily evaluated by degradation of 4-tert-butylphenol (PTBP), which found 1.0 wt% h-BN/Bi4O5Br2-LMs to be the best one. The photocurrent experiments showed that the photocurrent density of 1.0 wt% h-BN/Bi4O5Br2-LMs was four times higher than that of pure Bi4O5Br2-LMs due to enhanced charge transfer ability of the former. It revealed that the addition of h-BN was in favor of suppressing the photoinduced electron-hole pair recombination of Bi4O5Br2-LMs, so as to improve the photocatalytic activity of the composite. O2− and h+ were proved to be the main reactive species in the photocatalytic process by scavenger experiments and electron paramagnetic resonance (EPR) spectra. In addition, the photocatalytic mechanism of h-BN/Bi4O5Br2-LMs was further elaborated in this work. The probable degradation products were identified by GC–MS. The proposed conjugated addition and oxidation reactions were described to be the main pathways by combining the frontier electron density calculation and GC–MS results.

The novel Bi-rich Bi 4 O 5 Br 2 with tunable morphologies of two-dimentional (2D) nanosheets (NSs), three-dimentional (3D) monodisperse layered microspheres (LMs) and hollow spheres (HSs) have been successfully synthesized via an ionic liquid-in-water (IL/W) microemulsion method. Surfactant TX-100 served as the stabilizer of the IL/W microemulsion, and its concentration significantly influenced the morphology and size of the resulting Bi 4 O 5 Br 2 crystal. Possible formation mechanisms have also been discussed. UV–vis diffuse-reflectance spectra and Density function theory (DFT) calculations indicated that Bi 4 O 5 Br 2 possessed stronger visible light adsorption and more negative conduction band minimum (CBM), which is beneficial to effectively activate molecular oxygen to produce O 2 − . The photocatalytic activity of Bi-rich Bi 4 O 5 Br 2 with varied shapes was investigated and compared with BiOBr for the removal of fungicide o-phenylphenol (OPP) and antibacterial agent norfloxacin (NOR) and tetracycline hydrochloride (TC) under visible light irradiation. The as-prepared Bi 4 O 5 Br 2 HSs and LMs possess higher photocatalytic efficiency than Bi 4 O 5 Br 2 and BiOBr NSs, which is attributed to the hollow/layered spherical structures and Bi-rich strategies. The O 2 − and h + are identified to be the major photoactive species during the photo-degradation process by scavenger experiments and EPR methods. This study is expected to provide a stepping stone to purposively design and explore other novel hollow structures with controllable morphology and enhanced photocatalytic activity.

Magnetically separable bismuth ferrite (BiFeO3) nanoparticles were fabricated by a citrate self-combustion method and coated with titanium dioxide (TiO2) by hydrolysis of titanium butoxide (Ti(OBu)4) to form BiFeO3@TiO2 core–shell nanocomposites with different mass ratios of TiO2 to BiFeO3. The photocatalytic performance of the catalysts was comprehensively investigated via photocatalytic oxidation of methyl violet (MV) under both ultraviolet and visible-light irradiation. The BiFeO3@TiO2 samples exhibited better photocatalytic performance than either BiFeO3 or TiO2 alone, and a BiFeO3@TiO2 sample with a mass ratio of 1:1 and TiO2 shell thickness of 50–100 nm showed the highest photo-oxidation activity of the catalysts. The enhanced photocatalytic activity was ascribed to the formation of a p-n junction of BiFeO3 and TiO2 with high charge separation efficiency as well as strong light absorption ability. Photoelectrochemical Mott–Schottky (MS) measurements revealed that both the charge carrier transportation and donor density of BiFeO3 were markedly enhanced after introduction of TiO2. The mechanism of MV degradation is mainly attributed to hydroxyl radicals and photogenerated electrons based on energy band theory and the formation of an internal electrostatic field. In addition, the unique core–shell structure of BiFeO3@TiO2 also promotes charge transfer at the BiFeO3/TiO2 interface by increasing the contact area between BiFeO3 and TiO2. Finally, the photocatalytic activity of BiFeO3@TiO2 was further confirmed by degradation of other industrial dyes under visible-light irradiation.

Ultrathin BiOCl half-shells have been synthesized via an ionic liquid-in-water (IL/W) microemulsion, applying the liquid–liquid boundary of the emulsion system as a template. Surfactant TX-100 acted as the stabilizer of the IL-microemulsion, which is of critical importance for the formation of BiOCl half-shells. The hollow structures were characterized using X-ray diffraction, scanning and transmission electron microscopy, diffuse reflectance spectroscopy and specific surface area, respectively. Possible formation mechanisms for the BiOCl half-shells were discussed. Moreover, the ultrathin BiOCl half-shells exhibited distinctly enhanced photocatalytic efficiency toward the degradation of colourless ciprofloxacin (CIP, a representative broad-spectrum antibiotic agent) under solar light irradiation as compared to BiOCl nanosheets. The photogenerated reactive species are verified by scavenger experiments, which reveals that O2−and h+ were the two major photoactive species toward the photodegradation of CIP over ultrathin BiOCl half-shells under solar-light. The enhanced activities of ultrathin BiOCl half-shells were mainly ascribed to the synergistic effect of the increased light-harvesting, larger BET surface area, faster separation and transfer of electron-hole pairs. It is hoped that the ionic liquid microemulsion-mediated route can be extended to the purposive design and fabrication of other halogen-containing inorganic hollow materials.

Nitinol alloy occluders are widely used in the transcatheter intervention treatment of congenital heart diseases like patent ductus arteriosus (PDA). However, nitinol alloy contains high levels of nickel, which can lead to toxic effects in the immune and hematopoietic systems if released in sufficient quantities. A new type of single-rivet occluder coated with nano-film has been developed to limit the release of nickel. In total, 23 patients were recruited and randomly assigned to the experimental group (n=12) with the new nano-film single-rivet occluders or the control group (n=11) with the traditional occluders. One case in the control group was lost to follow-up. The remaining 22 cases were followed up at 24 h, 7 days, 1 month, 3 months, and 6 months after the procedure. There were no statistically significant differences in routine blood test, alanine aminotransferase, creatinine, and troponin between the experimental and control groups. Serum nickel concentration in both two groups increased at 24 h after the procedure, peaked at 1 month, and returned to preoperative levels at 6 months. Serum nickel levels in the experimental group were significantly lower than in the control group at 24 h, 7 days, 1 month, and 3 months after the procedure. These data suggested that the nano-film coating effectively prevented nickel release from the new occluders, and therefore has a preferable safety profile.

The purpose of this study was to validate a method for determine the glomerular filtration rate (GFR) in healthy cynomolgus monkeys by using iohexol. Eighteen healthy cynomolgus macaque monkeys (age, 4 to 6 y [mean, 5 y]; weight, 2 to 6 kg [mean, 4 kg]) were randomly entered into 3 different doses groups (3 male and 3 female macaques per group) of 30, 60, 90 mg I/kg to receive an intravenous bolus injection of iohexol. Serum iohexol concentrations were determined by using liquid chromatography–tandem mass spectrometry, and clearance rate were determined by using WinNonlin software. The GFR value (mean ± SD) of each dose group was 2.50 ± 0.321, 2.65 ± 0.529, and 2.75 ± 0.385 mL/min/kg. These values did not differ significantly between dose levels or sexes. Iohexol clearance is a simple, precise method that is suitable for the determination of GFR in cynomolgus monkeys.

It is a classical result that prime numbers of the form $x^2+ny^2$ can be characterized via class field theory for an infinite set of $n$. In this paper we derive the function field analogue of the classical result. Then we apply an effective version of the Chebotarev density theorem to bound the degree of the smallest irreducible of the form $x^2-dy^2$, where $x$, $y$, and $d$ are elements of a polynomial ring over a finite field.

Modern technology often generates data with complex structures in which both response and explanatory variables are matrix-valued. Existing methods in the literature are able to tackle matrix-valued predictors but are rather limited for matrix-valued responses. In this article, we study matrix-variate regressions for such data, where the response Y on each experimental unit is a random matrix and the predictor X can be either a scalar, a vector, or a matrix, treated as non-stochastic in terms of the conditional distribution Y|X. We propose models for matrix-variate regressions and then develop envelope extensions of these models. Under the envelope framework, redundant variation can be eliminated in estimation and the number of parameters can be notably reduced when the matrix-variate dimension is large, possibly resulting in significant gains in efficiency. The proposed methods are applicable to high dimensional settings., Comment: 28 pages, 4 figures