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Within the Bayesian framework using an explicitly isospin-dependent parametric equation of state (EOS) for the core of neutron stars (NSs), we study how the NS EOS behave when we confront them with the tidal deformabilities $\Lambda_{1.4}$ of canonical NSs with different error and different lower boundaries, and with the tidal deformabilities of the massive NSs. We found that it will not highly improve the constraints on the NS EOS but have a weak effect on narrowing down the slope parameter of the symmetry energy by decreasing the measurement errors of $\Lambda_{1.4}$. Both the isospin-dependent and isospin-independent parts of the NS EOS are significantly constrained and raised as the tidal deformabilities of the massive NSs are adopted in the calculations, especially in high-density regions. It is also found that $\Lambda_{1.4}$ is more competent to limit the curvature parameter than the slope parameter of the symmetry energy, whereas the opposite case happens for the radius of canonical NSs $R_{1.4}$. The tidal deformability of the NS with two times of solar mass $\Lambda_{2.0}$ is more sensitive to the skewness than curvature parameter of the symmetry energy, and $\Lambda_{1.4}$ and $R_{1.4}$ have no correlation with the former.

Au-n-octanedithiol-Au molecular junction (Au-SC8S-Au) has been investigated using density functional theory combined with the nonequilibrium Green’s function approach. Theoretically calculated results are used to build the relationship between the interface binding structures and single-molecule quantum conductance of n-octanedithiol (SC8S) embodied in a gold nanogap with or without stretching forces. To understand the electron transport mechanism in the single molecular nanojunction, we designed three types of Au-SC8S-Au nanogaps, including flat electrode through an Au atom connecting (Model I), top-pyramidal or flat electrodes with the molecule adsorbing directly (Model II), and top-pyramidal Au electrodes with Au atomic chains (Model III). We first determined the optimized structures of different Au-SC8S-Au nanogaps, and then predicted the distance-dependent stretching force and conductance in each case. Our calculated results show that in the Model I with an Au atom bridging the flat Au (111) gold electrodes and the SC8S molecule, the conductance decreases exponentially before the fracture of Au–Au bond, in a good agreement with the experimental conductance in the literature. For the top-pyramidal electrode Models II and III, the magnitudes of molecular conductance are larger than that in Model I. Our theoretical calculations also show that the Au–Au bond fracture takes place in Models I and III, while the Au–S bond fracture appears in Model II. This is explained due to the total strength of three synergetic Au–Au bonds stronger than an Au–S bond in Model II. This is supported from the broken force about 2 nN for the Au–Au bond and 3 nN for the Au–S bond.

The reduction of nitrogen-containing heterocyclic compounds in aqueous medium under mild condition is quite challenging. In view of metal–organic frameworks (MOFs) possess adjustable pore size and modifiable organic linkers, MOFs could be used in heterogeneous catalysis. Herein, Three Nano-Ni-MOFs, MOF-74-Ni, MOF-69-Ni, and Ni–NH2 (constructed from similar ligands and Ni2+ ions) are introduced for hydrogenating of azacyclo-compounds. As expected, Ni–NH2 shows outstanding activity of hydrogenation of quinoline under mild conditions, due to the moderate pore size and the modified –NH2 function group, which makes the substrate anchored on the surface of the framework facilitate the following catalysis process. Theoretical calculations identified that the –NH2 group at the catalyst facilitates the H2 heterolytic dissociation for the hydrogenation reactions. Compared to MOF-74-Ni and MOF-69-Ni, the catalyst of Ni–NH2 shows outstanding activity of hydrogenation of quinoline, due to the modified –NH2 function group which makes the substrate anchored on the surface of the framework facilitate the following catalysis process

A new chromene derivative, alternapyran (1), along with three known compounds (2–4), was isolated from the Alternaria sp. ZG22 obtained from a Dasymaschalon rostratum collected from the Hainan. The structure of the new compound 1 was elucidated by NMR and mass spectroscopic data. Compounds 2 and 3 showed broad spectrum antibacterial activity against four terrestrial pathogenic bacteria.

The development of nonprecious catalysts for hydrogenation of organic molecules is of great importance in heterogeneous catalysis. Herein, we report a series of N-doped hollow carbon frameworks encompassing cobalt nanoparticles (denoted as Co@NHF-900) constructed as a new kind of reusable catalyst for this purpose by pyrolysis of ZIF-8@Co-dopamine under Ar atmospheres. Notably, the framework of ZIF-8 is essential for efficient catalyst by providing a carbon framework to support Co-dopamine. The experimental results reveal that the ZIF-8 renders a large hollow place within the catalysts, allowing the enrichment of the substrate and windows of the hollow structure and the ease of mass transfer of products during the reaction. All of the virtues made Co@NHF-900 a good candidate for hydrogenation of quinolines with high activity (TOF value of 119 h-1, which is several times than that of akin catalysts) and chemoselectivity.

The aim of this study was to investigate the changes of retinal vessel density (VD) and choriocapillary blood flow area (CBFA) in macula after an acute intraocular pressure (IOP) elevation observed using optical coherence tomography angiography. This was a prospective comparative study of subjects with narrow anterior chamber angles who underwent laser peripheral iridotomies (LPIs). The IOP was measured before and 1 hour after the LPI. The retinal VDs and CBFAs of the macula were measured using optical coherence tomography angiography at the baseline and 1 hour after the LPI. A total of 88 eyes of 88 individuals were enrolled in our study, and 70 eyes of 70 individuals finally completed the study with a mean IOP rise of 10.2 ± 7.5 mm Hg after the LPI. The VDs and areas of foveal avascular zone of all of the subjects did not differ significantly between the measurements obtained at the baseline and 1 hour after the LPI (P > .05). However, there were statistically significant differences in the CBFAs at the baseline and 1 hour after the LPI (P 20 mmHg. The VDs of the macula measured at the baseline were significantly different from the measurements obtained 1 hour after the LPI in group C in either the superficial retinal layer or deep retinal layer (P

Finding a highly efficient electro-catalyst for ethanol oxidation is the central issue in the use of direct ethanol fuel cells. Recently, fabricating interfacial sites between two phases has been reported as an effective approach to boost the heterogeneous catalytic activity. In this work, a comprehensive understanding of how the Pt/Rh(1 1 1) interface promotes ethanol electro-oxidation for direct ethanol fuel cells at atomic levels is gained by employing density functional theory (DFT) calculations. It is found that the Pt/Rh(1 1 1) interface including (1 1 1) × (1 1 0) and (1 1 1) × (1 0 0) could effectively convert ethanol to CH3CO* and the Rh(1 1 1) surface could activate water at low potentials (

Using a pulsed laser deposition method, the electron-doped La0.85Hf0.15MnO3 (LHMO) film with the thickness of 90 nm was epitaxially grown on LaAlO3 (001) single crystal substrate. The structural, magnetic and electrical transport properties of the film have been studied comprehensively. The X-ray diffraction patterns confirm that LHMO film is of single phase, good quality and c axis orientation. The film undergoes a ferromagnetic-like ordering to paramagnetic states at T C =280 K. Moreover, a spin glass behavior observed in the film may be attributed to the strain effects. Using the percolation theory, we have analyzed the resistivity data ρ (T) of the film and given an excellent fit in the whole temperature range. Particularly, large temperature coefficient of resistance of 11.27% K− 1 has been discovered near sub-room-temperature, indicating that LHMO film could be useful for bolometric applications.