Benzimidazolium 2-(2,4-dichloro­phen­oxy)acetate monohydrate

In the crystal of the title hydrated mol­ecular salt, C7H7N2 +·C8H5Cl2O3·H2O, the components inter­act by way of N—H⋯O and O—H⋯O hydrogen bonds, leading to chains propagating in [100]

Polysaccharides from the Medicinal Mushroom Cordyceps taii Show Antioxidant and Immunoenhancing Activities in a D-Galactose-Induced Aging Mouse Model

Cordyceps taii, an edible medicinal mushroom native to south China, is recognized as an unparalleled resource of healthy foods and drug discovery. In the present study, the antioxidant pharmacological properties of C. taii were systematically investigated. In vitro assays revealed the scavenging activities of the aqueous extract and polysaccharides of C. taii against various free radicals, that is, 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and superoxide anion radical. The EC50 values for superoxide anion-free radical ranged from 2.04 mg/mL to 2.49 mg/mL, which was at least 2.6-fold stronger than that of antioxidant thiourea. The polysaccharides also significantly enhanced the antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase) and markedly decreased the malondialdehyde production of lipid peroxidation in a D-galactose-induced aging mouse model. Interestingly, the immune function of the administration group was significantly boosted compared with the D-galactose-induced aging model group. Therefore, the C. taii polysaccharides possessed potent antioxidant activity closely associated with immune function enhancement and free radical scavenging. These findings suggest that the polysaccharides are a promising source of natural antioxidants and antiaging drugs. Consequently, a preliminary chemical investigation was performed using gas chromatography-mass spectroscopy and revealed that the polysaccharides studied were mainly composed of glucose, mannose, and galactose. Fourier-transform infrared spectra also showed characteristic polysaccharide absorption bands

Molecular states from BˉN\bar{B}N interactions

In 2019, two new structures $\Lambda_b(6146)^0$ and $\Lambda_b(6152)^0$ at the invariant mass spectrum of $\Lambda_b^0\pi^{+}\pi^{-}$ observed by the LHCb Collaboration triggers a hot discussion about their inner structure. Although many works study seem to indicate that these two states are conventional three-quark states, $\Lambda_b(6146)^0$ and $\Lambda_b(6152)^0$ might still be $\bar{B}N$ hadronic molecule state, because the mass of $\Lambda_b(6146)^0$ and $\Lambda_b(6152)^0$ are close to the $\bar{B}N$ threshold. In this work, we perform a systematical investigation of the possible heavy molecular states from the interaction of $\bar{B}N$ in a one-boson-exchange approach. The interaction of the system considered is described by the $t$-channel $\sigma$, $\omega$, and $\rho$ mesons exchange. With the one-boson-exchange potentials obtained, the $\bar{B}N$ bound states with different quantum number configurations are got by solving the non-relativistic Schr\"{o}dinger equation. Our calculation suggests that recently observed $\Lambda_b(6146)^0$ can be assigned as a $P$-wave molecular state of $\bar{B}N$ with $I(J^P)=0(3/2^{+})$. However, the $\Lambda_b(6152)^0$ state cannot be accommodated in the current $F$-wave $\bar{B}N$ molecular picture. The calculation also favors the existence of a $S$-wave $\bar{B}N$ state that can not be associated with the $\Lambda_b(5912)^0$. The results in this work are helpful for understanding the high wave molecular states, and future experimental search for the new molecular states

Development of a thiophene derivative modified LDH coating for Mg alloy corrosion protection.

A new thiophene derivative corrosion inhibitor (CI) was developed to functionalize the layered double hydroxide (LDH) primer on Mg alloy to enhance corrosion protection. Compared with bare LDH coating, the composite coatings consisting of a MgAl-LDH primer and an outer CI layer showed highly compact surface structures without large pores and gaps, thereby indicating the enhanced capability to resist the penetration of corrosive species. Electrochemical tests revealed that the MgAl-LDH film modified with the newly synthesized CI exhibited higher charge transfer resistance and lower corrosion current density than films modified with commercial CIs. The highest enhancement in corrosion resistance was linked to the film's ability to repair physical damage by forming precipitates through chemical complexation and adsorption of the CIs. These findings open up new opportunities for the design and synthesis of a thiophene-contained inhibitor to modify LDH films and to obtain a composite coating with superior corrosion protection

Stochastic Electron Acceleration in Shell-Type Supernova Remnants II

We discuss the generic characteristics of stochastic particle acceleration by a fully developed turbulence spectrum and show that resonant interactions of particles with high speed waves dominate the acceleration process. To produce the relativistic electrons inferred from the broadband spectrum of a few well-observed shell-type supernova remnants in the leptonic scenario for the TeV emission, fast mode waves must be excited effectively in the downstream and dominate the turbulence in the subsonic phase. Strong collisionless non-relativistic astrophysical shocks are studied with the assumption of a constant Aflven speed. The energy density of non-thermal electrons is found to be comparable to that of the magnetic field. With reasonable parameters, the model explains observations of shell-type supernova remnants. More detailed studies are warranted to better understand the nature of supernova shocks.Comment: 5 pages, 7 figures, submitted to Proceedings of the Conference on "2008 Heidelberg International Symposium on High Energy Gamma-Ray Astronomy