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The health-promoting properties and chemical profiles of 30 Jew’s ear mushroom varieties were investigated. The antioxidant properties were determined by ferric reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging, and metal chelating ability (MCA) assays, while phenolic profiles were determined by total phenol content (TPC) and total flavonoid content (TFC) colorimetric assays. Total carbohydrate, β-glucan, and melanin contents were determined by colorimetric methods. 5'-Nucleotides, vitamin D2, ergosterol, and ergothioneine contents were determined by high performance liquid chromatography (HPLC). Anti-inflammation activities of Jew’s ear were evaluated by the colorimetric protease inhibitory method. The results showed that Jew’s ear mushrooms possessed substantial phenolics and antioxidant properties. All the Jew’s ear varieties contain high amount of total carbohydrate, β-glucan, reducing sugar, melanin, pectin, vitamin D2, ergosterol, and ergothioneine. The current findings could provide scientific information for breeders to nurture desired varieties and for food industry to develop new health promoting products.

Chromium iodide monolayers, which have different magnetic properties in comparison to the bulk chromium iodide, have been shown to form skyrmionic states in applied electromagnetic fields or in Janus-layer devices. In this work, we demonstrate that spin-canted solutions can be induced into monolayer chromium iodide by select substitution of iodide atoms with isovalent impurities. Several concentrations and spatial configurations of halide substitutional defects are selected to probe the coupling between the local defect-induced geometric distortions and orientation of chromium magnetic moments. This work provides atomic-level insight into how atomically precise chemical doping can be used to create and control complex magnetic patterns in chromium iodide layers and lays out the foundation for investigating the field- and geometric-dependent magnetic properties in similar two-dimensional materials.

Abstract

Defects within nanodiamonds have enabled a variety of quantum sensors based on optical properties that are sensitive to pressure, optical/electric fields, and the configuration of both electronic and nuclear of spins. The presence of dopants can introduce midgap states influencing their optical properties. Complex defects based on nitrogen aggregates have been shown to form in nitrogen-containing diamonds; as such, it is important to differentiate these systems from pure diamond and single nitrogen vacancy (NV) systems. Here we report the effect of N4VxB- and H4-aggregate defects on the infrared vibrational, optical, and X-ray absorption spectroscopies of nanodiamonds. It is found that the presence of these polyatomic nitrogen-aggregate defects introduces unique vibrational responses, as well as electronic levels giving rise to unique optical and X-ray absorption features.

To advance the utilization of solar thermal energy, a novel solar-driven microcapsule was designed by the combination of high-performance CuS nanoconverter and the microencapsulated n-Eicosane with a brookite TiO2shell via in situsol–gel method. The resultant n-Eicosane@TiO2/CuS microcapsules possessed excellent thermal properties with high latent heat density (171.7 J/g), high encapsulation efficiency (71.7%), and increased thermal conductivity (0.730 W/(m K)). SEM analysis clearly verified that CuS nanoparticles exhibited a uniform distribution on the surfaces. Most of all, the addition of CuS not only enlarged the absorption spectra from the UV to the visible and NIR region but also achieved high solar-to-thermal conversion efficiency (94.41%). Due to the high heat storage capability and solar irradiation utilization efficiency, this solar-driven microcapsule possesses great potential for the solar energy utilization.

The homotopy perturbation method with an auxiliary term is applied to obtain an approximate analytical solution for the tangent nonlinear packaging system. To further raise the accuracy of the solution, this work has expanded the possibility of the energy method for the homotopy perturbation method with an auxiliary term. And then, the amplitude and frequency of the tangent nonlinear packaging system can be calculated. The results show that the solution is in good consistent with the numerical solution solved by the Runge–Kutta method. It can be concluded that the proposed method is suitable for the optimal design of a tangent nonlinear packaging system.

This study conducted a comparative analysis to characterize crude polysaccharides from seven selected strains of Auricularia corneain China, including commercial, hybrid, and wild domesticated strains. The obtained crude polysaccharide samples were analyzed using electron microscope-energy dispersive X-ray (SEM-EDX), Fourier transform infrared (FTIR) spectroscopy, and for their monosaccharide composition. The results revealed that crude polysaccharide samples were mainly composed of 85.9% mannose and 12.3% glucose. Among the strains tested, Ac1 and Ac33 exhibited significantly higher total polysaccharide content (215.9±2.4 mg/g and 200.3±1.5 mg/g, respectively) and phenolic content (40.2±4.0 mg GAE/g and 44.2±2.7 mg GAE/g, respectively). Additionally, Ac33 and Ac24 showed the highest levels of DPPH radical scavenging and ABTS scavenging ability among the strains tested. Overall, the results suggest that the crude polysaccharides from A. corneahave the potential as a natural source of antioxidant and antimicrobial agents and could be developed into functional nutritional foods.

To achieve long-term effective protection of food by continuously controlling the release of active substances in an active film, IRMOF-3 was post-synthetic modified with benzoic acid (BA) to obtain BA-IRMOF-3. This modification enhanced the loading capacity of carvacrol (CA) and slowed down its release rate. Research on IRMOF-3 synthesis has found that increasing the proportion of metal nodes can improve its crystallinity. The post-synthesis modification of IRMOF-3 through amide reaction successfully enhanced the binding energy with CA from −5.1 kcal/mol to −6 kcal/mol, resulting in an improved CA loading rate of 28.62% ± 0.15% and delayed release. Furthermore, the BA-IRMOF-3/CA assembly was added to the sodium alginate matrix to prepare the active film BMC@SA, which improved the mechanical and physical properties of the film. The release and antibacterial/antioxidant properties were investigated. The results demonstrated that the active film BMC@SA exhibited significant sustained-release properties and antibacterial/antioxidant activities, reducing the growth of E. coliand S. aureusby 61.95% and 49.33% respectively. In refrigerated pork experiments, the film BMC@SA slowed down the color, weight, pH changes and inhibited microbial growth of fresh pork effectively, and extended the shelf life of pork from 6 d to 12 d, which demonstrated the potential application of active film BMC@SA in food preservation.

The direct probing of photochemical dynamics by detecting the electronic coherence generated during passage through conical intersections is an intriguing challenge. The weak coherence signal and the difficulty in preparing purely excited wave packets that exclude coherence from other sources make it experimentally challenging. We propose to use time-resolved X-ray magnetic circular dichroism to probe the wave packet dynamics around the conical intersection. The magnetic field amplifies the relative strength of the electronic coherence signal compared to populations through the magnetic field response anisotropy. More importantly, since the excited state relaxation through conical intersections involves a change of parity, the magnetic coupling matches the symmetry of the response function with the electronic coherence, making the coherence signal only sensitive to the conical intersection induced coherence and excludes the pump pulse induced coherence between the ground state and excited state. In this theoretical study, we apply this technique to the photodissociation dynamics of a pyrrole molecule and demonstrate its capability of probing electronic coherence at a conical intersection as well as population transfer. We demonstrate that a magnetic field can be effectively used to extract novel information about electron and nuclear molecular dynamics.

Advanced shape-stable phase change materials (SSPCMs) with environment self-adaptation are becoming more meaningful in regulating temperature in diverse applications. In this manuscript, a series of self-healing SSPCMs containing ionic liquids were fabricated by temperature-responsive polymers (PNIPAM) through the free radical polymerization method. 1-ethyl-3-methylimidazolium dicyanamide ([Emim][DCA]) ionic liquid was selected as the cooling agent and PCM. 2-ureido-4[1H]-pyrimidinone (UPy) and chitosan oligosaccharide (COS) were chosen as modifiers. Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy were used to determine the chemical structure. The surface morphology of SSPCMs was observed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and polarizing optical microscopy (POM). A rotational rheometer and electronic universal testing machine were used to assess the self-healing effectiveness and mechanical properties of SSPCMs. Thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to examine the thermal characteristics and thermal reliabilities of self-healing SSPCMs. The results indicate that the self-healing efficiency of SSPCM is 91.04 % within 5 min, and compressive strength is improved by 65.7 % by the ionic liquid. The SSPCMs perform thermo-sensitive properties, which allow SSPCMs to maintain a stable shape in response to temperature change and reduce PCMs leakage. Furthermore, the SSPCMs can quickly and effectively recover their mechanical properties after damage thanks to the excellent self-healing properties. Meanwhile, the SSPCMs have a longer lifespan for improving recycling efficiency and are more environmentally friendly. The developed SSPCMs with recycle stability have a high energy density (251.5 J/g) and adjustable phase change temperature properties. The developed SSPCMs can be made to fit various temperature applications by changing the concentration of ionic liquids in the phase change system. Overall, the SSPCMs show promising potential for cold energy storage and thermal management.

AbstractThe land-atmosphere interaction processes are unique at Mt. Everest as a result of high elevation. Based on turbulent data collected from April 2005 to March 2006 with the eddy covariance method at Quzong in the Rongbu Valley on the northern slope of Mt. Everest, land-atmosphere energy budget before and after the southwest monsoon onset and surface layer turbulent characteristics are studied for the first time. It is found that energy budget components (net radiation flux, sensible heat flux, latent heat flux, and soil heat flux) and surface heating field have strong diurnal and seasonal variations. In particular, under the influence of the southwest monsoon, the characteristics of surface parameters can be clearly identified. From pre-monsoon to monsoon season, the sensible heat flux decreases whereas the latent heat flux increases. The latent heat flux and Evaporative Fraction at Quzong are relatively high most of the year. Furthermore, the intensity of heating source in the wet season (from June to August) is much greater than that in the dry season (from October to December). The relationship between normalized standard deviation of wind speed and atmospheric stability, variations of normalized standard deviation of temperature, and humidity with atmospheric stability are analyzed using the Monin-Obukhov similarity theory. The result reveals that the normalized standard deviation of velocity components of the three-dimensional wind speed follows similarity relationships in the convective and near-neutral surface layer, but does not seem to be valid in stable surface layer. However, the normalized standard deviation of temperature and humidity does not obey Monin-Obukhov similarity theory in the entire interval of atmospheric stratifications.

In this work we develop a variational relativistic density matrix renormalization group (DMRG) approach within the exact-two-component (X2C) framework (X2C-DMRG), using spinor orbitals optimized with the two-component relativistic complete active space self-consistent field. We investigate fine-structure splittings of p- (Ga, In, Tl) and d-block (Sc, Y, La) atoms and excitation energies of monohydride molecules (GeH, SnH, and TlH) with X2C-DMRG calculations using an all-electron relativistic Hamiltonian in a Kramers-unrestricted basis. We find that X2C-DMRG yields accurate 2P and 2D splittings compared to multireference configuration interaction with singles and doubles (MRCISD). We also investigated the degree of symmetry breaking in the atomic multiplets and convergence of electron correlation in the total energies. Symmetry breaking can be large in some cases (∼30 meV); however, increasing the number of renormalized block states mfor the DMRG optimization recovers the symmetry breaking by several orders of magnitude. Encouragingly, we find the convergence of electron correlation to be close to MRCISDTQ5 quality. Relativistic X2C-DMRG approaches are important for cases where spin–orbit coupling is significant and the underlying reference wave function requires a large determinantal space. We are able to obtain quantitatively correct fine-structure splittings for systems up to 1019number of determinants with traditional CI approaches, which are currently unfeasible to converge for the field.

As the relativistic corrections become stronger for late-row elements, the fully perturbative treatment of spin–orbit coupling and dynamic correlation may become inadequate for accurate descriptions of chemical properties. In this work, we introduce a determinant-based Kramers-unrestricted exact-two-component multireference second-order perturbation (X2C-MRPT2) method which variationally includes relativistic corrections with a perturbative dynamic correlation. The restricted active space partitioning scheme is employed to provide an adjustable correlation space for the second-order perturbation treatment. The multistate perturbation theory is also developed to improve the descriptions of ground and excited states. Benchmark studies of atomic fine-structure splittings and spectroscopic constants of molecular monohydrides using X2C-MRPT2 are compared to the other perturbative and variational approaches. The results suggest that X2C-MRPT2 is a highly accurate alternative to the fully variational multireference configuration interaction method at only a small fraction of the computational cost.

ABSTRACTThe Normalized Difference Vegetation Index (NDVI) derived from NOAA AVHRR Global Vegetation Index (GVI) for Lhasa area in the central Tibetan Plateau from 1985 to 1999 and its relationship with climate conditions (precipitation and temperature) are established in this study. Climate data from the Lhasa meteorological station provided by the Tibet Climate Data Center are used for this analysis. The NDVI-derived vegetation growth patterns show very strong seasonal cycles and interannual variations. The growing season length varies between years. The correlation between NDVI and precipitation (r= 0.75, P< 0.01) in Lhasa area is higher than the correlation between NDVI and temperature (r= 0.63, P< 0.01), suggesting that NDVI is more sensitive to precipitation than temperature in this semiarid climate zone. Furthermore, the time series of NDVI demonstrate a positive trend from 1985 to 1999, which means that the vegetation biomass present on land surface is increasing. This trend is strongly correlated to increased rainfall and temperature from mid-1980s to 1990s in the Lhasa area of the Tibetan Plateau.

X-ray absorption spectroscopy is a powerful probe of local electronic and nuclear structures, providing insights into chemical processes. The theoretical prediction and interpretation of metal L-edge X-ray absorption spectra are complicated by both relativistic effects, including spin–orbit coupling and the multiconfigurational nature of the states involved. This work details an exact two-component multireference restricted active space (RAS) configuration interaction scheme that uses an exact two-component state-averaged complete active space self-consistent-field method, which includes the spin–orbit coupling in a variational manner, for the accurate description of the electronic structure before using a RAS configuration interaction method to describe the core excited states of the X-ray spectrum. Benchmark calculations are presented for a series of iron-containing complexes, with results showing key features of the spectrum being reproduced, including ligand-to-metal charge transfer and shake-up excitations.