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The detection of the high-energy (∼290 TeV) neutrino coincident with the flaring blazar TXS 0506+056, the first and only 3σ neutrino-source association to date, provides new, multimessenger tests of the weak equivalence principle (WEP) and Lorentz invariance. Assuming that the flight time difference between the TeV neutrino and gamma-ray photons from the blazar flare is mainly caused by the gravitational potential of the Laniakea supercluster of galaxies, we show that the deviation from the WEP for neutrinos and photons is conservatively constrained to have an accuracy of 10 − 6 – 10 − 7 , which is 3–4 orders of magnitude better than previous results placed by MeV neutrinos from supernova 1987A. In addition, we demonstrate that the association of the TeV neutrino with the blazar flare sets limits on the energy scales of quantum gravity for both linear and quadratic violations of Lorentz invariance (LIV) to E QG , 1 > 3.2 × 10 15 – 3.7 × 10 16 GeV and E QG , 2 > 4.0 × 10 10 – 1.4 × 10 11 GeV. These improve previous limits on both linear and quadratic LIV energy scales in neutrino propagation by 5–7 orders of magnitude.

Charge-transfer (CT) is an important enhancement mechanism in the field of surface-enhanced Raman scattering (SERS) that typically increases the Raman intensity of molecules by as much as 10-100 times. Herein, a low-cost Ag2O aggregates substrate was prepared via a facile chemical precipitation method, and the calculated CT-based enhancement factor of the uranyl ions adsorbed on it reached as high as 105, a metal-comparable value. The efficient photoinduced CT process from the valence band of Ag2O to the LUMO of uranyl ions under appropriate excitation sources resulted in the repulsion of the axial oxygen atoms of the O U O bond, which enhanced its polarizability, creating a more intense Raman mode. To the best of our knowledge, this study firstly reports such a strong photoinduced CT enhancement of uranyl ions, with concentrations of 10−8 mol L−1 or lower being detected using this Ag2O substrate. Most importantly, this research has shown that the photoinduced CT enhancement also contributes to the SERS of uranyl ions on pure Ag substrates which have often been ascribed to the electromagnetic enhancement in previous studies. In addition, Ag2O can be used to selectively detect uranyl ions without interference from many other molecules or ions because of the energy matching rule of the photoinduced CT process, which was readily available for uranyl detection in the environmental aqueous solution.

In this work, C-In2O3/BiOI composite is synthesized and used as a high performance photocatalyst for photocatalytic degradation of methyl blue (MB) in wastewater. The C-In2O3/BiOI composites demonstrate 5 times higher photocatalytic performance than the pristine BiOI and In2O3 for MB degradation under the irradiation of visible light. Furthermore, the C-In2O3/BiOI composites have excellent cycling stability. Such enhanced photoactivity is due to the significantly enhanced separation efficiency of photogenerated. This work provides some significance in the design and construction of environmentally benign catalysts with excellent photocatalytic degradation of toxic pollutants.

The rapid and efficient identification of uranium oxides is of great significance in the field of nuclear security. A feasible SERS strategy assisted by Ag2O for rapid detection of trace amount of uranium oxides (∼1.8 μg/mL for UO2 and ∼ 3.6 μg/mL for U3O8) was proposed and described. The effects of laser power on the Raman and SERS of uranium oxides were investigated. And the SERS mechanism was discussed by constructing several types of SERS substrates. Uranyl ions produced from hydrolysis and oxidation of uranium oxides are the key components for their SERS, where efficient photoinduced charge transfer process from Ag2O to uranyl ions occurs, resulting in a more intense Raman mode. The easily obtained but clearly distinguished SERS signals allow us to selectively and quickly detect the uranium oxides from mixtures, which may be practically applied to nuclear antiterrorism.

The main scientific goal of the LHAASO WFCTA experiment is to measure the cosmic ray energy spectra and composition from 10 TeV to 1 EeV. Cherenkov photons in the extensive air shower measured by the SiPM camera of Cherenkov telescopes can be used to reconstruct the cosmic ray energy. The absolute calibration of the camera is a crucial step to achieve the accurate measurement of the cosmic ray energy spectrum. A multi-wavelength cylindrical illuminator based on LEDs is developed and mounted inside the telescope to calibrate and monitor the camera, and the illuminator’s stability is better than 0.5% under the temperature variation from -26 to 26 ° C. A portable probe with a single photoelectron resolution of 21.6% is developed. After calibration by National Institute of Metrology, China (NIM), the probe is taken to the LHAASO site to measure the absolute photon density of the cylindrical illuminator inside the telescope. Based on the illuminator with known photon density, the photon conversion factor of the camera can be calibrated, and the overall calibration uncertainty is less than 2.6%.

In this paper, a kind of graphene gel loading TBP inside, named as G-TBP-Gel was prepared via by mildly reducing the graphene oxide (GO) sheets in TBP/GO/water emulsion using ascorbic acid, which is facile and time-consuming. The G-TBP-Gel was constructed by approximately spherical pores built by reduced graphene oxide (rGO) sheets disorderly. The TBP droplets are fixed in the pores, and the total volume of TBP occupies nearly 90% volume of the G-TBP-Gel. We studied the capacities and distribution ratios of G-TBP-Gel in the application of uranium extraction under different conditions. Moreover, the G-TBP-Gel could be easily separated from the aqueous phase due to the fixation of the TBP. The residual oxygenated groups on the rGO sheets construct a network of water nano-channels, via which uranyl migrates in the process of extraction or stripping. Compared with traditional liquid-liquid extraction, the rates of extraction or stripping are much slower due to the structural factors, which still need promotion in the future.

U3O8, the most stable state of uranium oxides, is a key intermediate compound for pyroprocessing of used nuclear fuel. However, compared to UO2, the electro-deoxidation mechanism of U3O8 is still cursory due to the complicated U-O intermediate phases. In this paper, the electro-deoxidation processes of U3O8 were investigated via diverse methods. A molybdenum metallic cavity electrode loaded with U3O8 powder was adopted to investigate the electrochemical behavior via cyclic voltammetry and square wave voltammetry. Sintered U3O8 pellets were used as cathodes to obtain electrolytic products with varying applied voltages or duration time. The composition and microstructure of electrolytic products were characterized by Raman spectroscopy, X-ray diffraction, scanning electron microscope and energy dispersive spectrometer. Based on above analysis results, electro-reduction processes of porous U3O8 pellets were proposed. First, U3O8 undergoes a rapid transition to U4O9 (U4O9-y). Then, the intermediate compound was gradually reduced to UO2 from the outer layer to the center of the bulk due to the limited migration rate of O2−. Before the transformation completed, metallic U generated on the surface of the bulk through direct electro-deoxidation and Li metal thermal reduction. With the increase of porosity and the propagation of metal-oxide-electrolyte three-phase interline, the U3O8 pellet was finally reduced to metallic U bulk.

The electrochemical behavior of Pr(III) and formation process of Pr-Al intermetallics were investigated by different electrochemical methods. The reduction of Pr(III) ion to metallic Pr is an one-step three-electrons reaction. The reversibility of Pr(III)/Pr(0) system was evaluated by cyclic voltammograms with different scan rates. The co-reduction of Pr(III) and Al(III) ions formed three different Pr-Al intermetallics at electrode potentials around −1.40, −1.80, and −1.95 V vs. Ag/AgCl at 723 K, respectively. Open-circuit chronopotentiometry and electromotive force (emf) measurements were carried out to estimate the relative molar Gibbs energies of Pr for the formation of different Pr-Al intermetallics in the temperature range of 723–843 K. The activities of Pr in the Pr-Al intermetallic compounds were calculated.

We report on the facile, reliable fabrication of novel magnetic cucurbit[6]uril/graphene oxide (CB[6]/GO/Fe3O4) composite by using an in-situ co-precipitation method, for which the formation process and possible formation mechanism were also investigated. Moreover, the composite was used as an adsorbent for the removal of uranium(VI) from aqueous solution. Herein, GO nanosheets were chosen as a substrate to immobilize CB[6] and Fe3O4. During the co-precipitation of Fe3O4 nanoparticles on surface of GO nanosheets, CB[6] molecules was fixed through hydrogen bonding simultaneously. The as-prepared composite exhibited a high efficiency of magnetic separability, competitive adsorption performance and acceptable reusability and stability for U(VI) removal, indicating a potential application in uranium-bearing wastewater treatment.

Iron(II)-substituted LAU-zeotype aluminophosphate molecular sieve (denoted as FeAPO-LAU) was synthesized successfully by using imidazole as template in the solvothermal system. The detemplation process was studied to elucidate the stability and microporous characteristics of FeAPO-LAU. In situ temperature-dependent X-ray diffraction analyses indicated that the framework of FeAPO-LAU possessed higher thermal stability and maintained the framework integrity until 923 K. The organic templates could be removed by stage-temperature-programmed calcination using lower heating rate in O 2 atmosphere, which gave rise to the sample with surface areas of ca. 105 m 2 /g. NH 3 -temperature programmed desorption (NH 3 -TPD) analysis showed that detemplated FeAPO-LAU had a weak acidity. Magnetic measurement revealed that both as-synthesized and detemplated FeAPO-LAU showed antiferromagnetic behaviour.

In order to study the effect of dust extinction on the afterglow of gamma-ray bursts (GRBs), we carry out numerical calculations with high precision based on the rigorous Mie theory and the latest optical properties of interstellar dust grains, and analyze the different extinction curves produced by dust grains with different physical parameters. Our results indicate that the absolute extinction quantity is substantially determined by the medium density and metallicity. However, the shape of the extinction curve is mainly determined by the size distribution of the dust grains. If the dust grains aggregate to form larger ones, they will cause a flatter or grayer extinction curve with lower extinction quantity. On the contrary, if the dust grains are disassociated to smaller ones due to some uncertain processes, they will cause a steeper extinction curve with larger amount of extinction. These results might provide an important insight into understanding the origin of the optically dark GRBs.

A new open-framework aluminum-iron phosphate (C4H12N2)(2)[Fe2Al5(PO4)(8)(H2O)] (denoted as FeAPO-CJ51), with mixed-valence iron (II, III) has been hydrothermally synthesized by using piperazine as the template. The three-dimensional framework of FeAPO-CJ51 is constructed by the connection of metal-centered MOn (M = Fe/Al, n = 4, 5, 6) polyhedra and PO4 tetrahedra, which contains interconnecting 8-ring channels along the [010] and [001] directions. Diprotonated piperazine cations locate in the 8-ring channels to compensate the negative charge of the anionic framework. Mossbauer and magnetic susceptibility measurements show that equal amounts of Fe2+ and Fe3+ are present in FeAPO-CJ51, which undergo the long-range antiferromagnetic interactions.

The aim of this study was to compare the roles of dihydropyridine calcium antagonists nifedipine, nitrendipine, amlodipine on doxorubicin (DXR)-induced nephrotoxicity in rats using biochemical, histopathological and immunohistochemical approaches. Male Sprague-Dawley rats were randomly divided into five experimental groups: control; DXR; DXR+nifedipine (15 mg/kg); DXR+nitrendipine (10 mg/kg); DXR+amlodipine (5 mg/kg). Results showed that treatment with DXR alone caused significant changes in the levels of urinary protein, serum creatinine (SCr), and blood urea nitrogen (BUN). Co-administration with amlodipine effectively reversed the effect of DXR on these parameters. In contrast, nifedipine and nitrendipine either had no effect or worsened DXR induced changes in the levels of urinary protein, SCr and BUN. Furthermore, DXR treatment caused significant increases in the levels of malondialdehyde (MDA), nitric oxide (NO), nitric oxide synthase (NOS) and significant decreases in the levels of reduced glutathione (GSH), glutathione-S-transferase (GST), and superoxide dismutase (SOD). These effects were significantly reduced by co-administration with amlodipine but not affected by nifedipine and worsened by nitrendipine. In addition to the biochemical changes, histopathological studies showed that DXR caused significant structural damages in the kidneys. Glomerular cell apoptosis, a decrease in Bcl-2 expression and an increase in Bax expression were observed in all rats treated with DXR. Co-administration with amlodipine effectively reversed the effect of DXR while nifedipine and nitrendipine had no effect. In conclusion, this study clearly indicated that amlodipine protected against DXR-induced nephrotoxicity while nifedipine and nitrendipine had no effect.