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Black phosphorus (BP), as a two-dimensional material, has exhibited unique optoelectronic properties due to its anisotropic plasmons. In the present work, we theoretically propose a radiative thermal switch (RTS) composed of BP gratings in the context of near-field radiative heat transfer. The simply mechanical rotation between the gratings enables considerable modulation of radiative heat flux, especially when combined with the use of non-identical parameters, i.e., filling factors and electron densities of BP. Among all the cases including asymmetric BP gratings, symmetric BP gratings, and BP films, we find that the asymmetric BP gratings possess the most excellent switching performance. The optimized switching factors can be as high as 90% with the vacuum separation d=50 nm and higher than 70% even in the far-field regime d=1 µm. The high-performance switching is basically attributed to the rotatable-tunable anisotropic BP plasmons between the asymmetric gratings. Moreover, due to the twisting principle, the RTS can work at a wide range of temperature, which has great advantage over the phase change materials-based RTS. The proposed switching scheme has great significance for the applications in optoelectronic devices and thermal circuits.

Nowadays, the requirement for achieving dynamic radiative cooling is more and more intense, so a cooling system is proposed and developed to meet the demand in this paper. This cooling system is composed of a filter and a periodic trapezoidal VO 2 -Ge multilayer absorber (VGMA). The filter on the top enables the VGMA to reflect most of the solar irradiation at daytime and the absorptance or emittance of the VGMA is very different in the spectrum band of 8-13 μm for insulating and metallic VO 2 due to the phase transition characteristic of VO 2 . With this cooling system, close-to-zero absorptance in the range of 0.3-2.5 μm and high (low) absorptance from 8 to 13 μm are achieved for metallic (insulating) VO 2 . Based on changing the temperature and absorptivity or emissivity simultaneously, radiative heat can be transferred dynamically to the outer space. When VO 2 is in the insulating phase, the absorption mechanism of the absorber is magnetic resonance and surface plasmon polariton resonance, and broadband high absorptivity is achieved by exciting slowlight waveguide mode at broadband wavelengths when VO 2 is in metallic phase. The spectral absorptance characteristics of the absorber in the two phase states are investigated as a function of the layer number and the incident angle of the electromagnetic waves. The results show that the absorber designed is insensitive to the incident angle. Moreover, the net cooling power of the VGMA of metallic VO 2 is instantly 4 times more than that of insulating VO 2 once the phase change temperature is reached. This work will be beneficial to the advancement of dynamic radiative cooling.

Agglomeration and dispersion of nanoparticles control many important environmental processes. In this study, the particle size and zeta potential of ferrihydrite nanoparticles (FHNPs) and goethite nanoparticles (GTNPs) under different pH, ion, and organic matter conditions were measured. These data were used to calculate the Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energy between nanoparticles to further investigate the stability of two nanoparticles. The results showed that Na + and Ca 2+ promoted FHNPs and GTNPs agglomeration due to their ionic strength. The PO 4 3- with low-concentration (2 mmol·L -1 ), humic acid and fulvic acid (2 mg·L -1 and 10 mg·L -1 ) loaded on iron mineral nanoparticles changed their surface charge and further improved the stability of FHNPs and GTNPs at medium and high pH. Although the PO 4 3- with high concentration (10 mmol·L -1 ) also changed the electrical properties of iron mineral nanoparticles, it had little contribution to the GTNP stability due to its ionic strength. When the zeta potentials of FHNPs or GTNPs were close to 0, the primary barrier and secondary minima were nonexistent simultaneously. The two kinds of nanoparticles irreversibly agglomerated in primary minima. When the primary barrier and secondary minima coexisted, the proportion of reversible aggregation of FHNPs and GTNPs in secondary minima increased. The results provided support for further investigation of the environmental behavior of FHNPs and GTNPs, and iron mineral nanoparticle-facilitated transport of pollutants.

A two-dimensional optical parameter mapping based on the time-domain radiative transfer equation (TD-RTE) is studied in this work. The finite element method with structured and unstructured grids is employed to solve TD-RTE and OpenMP parallel technology is employed to improve the computing efficiency. The sequential quadratic programming algorithm is used as a powerful optimization method to reconstruct absorption and scattering parameter fields and the maximum a posteriori estimation is employed by introducing the regularization term into the objective function to improve the ill-posed inverse problem. In addition, the effects of measurement errors on reconstruction accuracy are investigated thoroughly. All the simulation results demonstrate that the reconstructed scheme we developed is accurate and efficient in optical parameter mapping based on TD-RTE.

Autophagy is a protecting intracellular pathway to transmit unnecessary or dysfunctional components to the lysosome for degeneration. Autophagic imbalance is connected with neurodegeneration. Neurodegenerative diseases including Parkinson's disease, Alzheimer's disease, and Huntington's disease are closely related to excitotoxicity and neuronal loss. Activation of G-protein-coupled receptor 30 (GPR30), an estrogen membrane receptor, protects neurons from excitotoxicity-induced cell death. However, whether autophagy is involved in the neuroprotective effect of GPR30 activation is not well-known. In this study, methyl thiazolyl tetrazolium (MTT), Western blot, monodansylcadaverine (MDC) staining, and immunofluorescent staining were employed to detect the role of autophagy in cultured primary cortical neurons after glutamate exposure and G1 treatment. Pretreatment of G1 (GPR30 specific agonist) reduced neuronal loss through inhibiting excessive autophagy induced by glutamate exposure, which was blocked by GPR30 antagonist G15, phosphatidylinositol-3-kinase (PI3K), and the mammalian target of rapamycin (mTOR) inhibitors. These data suggest that GPR30 protects neurons from cell loss primarily by modulating PI3K-AKT-mTOR signaling pathway. In addition, G1 alone did not affect the basal autophagy and cell viability. We conclude that GPR30 activation reduces glutamate-induced excessive autophagy in neurons and protects neurons against excitotoxicity.

In the present work, the near-field radiative heat transfer of a multilayered graphene system is investigated within the framework of the many-body theory. For the first time, the temperature distribution corresponding to the steady state of the system is investigated. Unique temperature steps are observed near both boundaries of the system, especially in the strong near-field regime. By utilizing the effective radiative thermal conductance, the thermal freedom of heat flux in different regions of the system is analyzed quantitatively, and the cause of various temperature distributions is explained accordingly. To characterize the heat transfer ability of the whole system, we evaluate the system with two heat transfer coefficients (HTC), transient heat transfer coefficient (THTC), and steady heat transfer coefficient (SHTC). A unique many-body enhancement is observed, which causes a red-shift of resonance peak corresponding to graphene surface plasmon polaritons. Furthermore, a three-body enhancement of SHTC emerges thanks to the relay effect and the complexity of the system. The regime of heat transport can be tuned by changing the chemical potentials of graphene and undergoes a transition from diffusive to quasi-ballistic transport in the strong near-field regime.

Four mononuclear lanthanide complexes containing 4'-phenyl-2,2':6',2″-terpyridine (ptpy), [Ln(NO 3 ) 3 (ptpy) (H 2 O)] (Ln = Eu ( 1 ), Gd ( 2 ), Tb ( 3 ), Dy ( 4 )), were solvothermally synthesized and characterized via elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction, and powder X-ray diffraction. Hirshfeld surfaces and the solid-state luminescence properties of the complexes were investigated. The 3-D Hirshfeld surface and 2-D fingerprint plots show that the main interactions are the O H/H O intermolecular interactions in 1 - 4 . Solid-state luminescence investigation reveals that Gd III complex 2 displays a ligand-centered emission and the Eu III , Tb III and Dy III complexes 1 , 3 and 4 show the characteristic lanthanide-centered luminescence upon UV excitations. The Eu III and Tb III complexes exhibit red (CIE: 0.6549, 0.3447) and green (CIE: 0.3760, 0.5412) luminescence in the solid state with quantum yields of 16.8% and 0.8% and lifetimes of 0.545 and 0.043 ms, respectively. Density functional theory (DFT) calculations were conducted to unravel the HOMO-LUMO energy gaps of the structures of ptpy and complexes 1 and 3 .

Dust intake is an important source of children's metal exposure. To explore the contamination level and health risk of toxic metals in kindergartens, surface dust samples were collected with self-made sampler in representative kindergartens in urban Beijing and concentrations of Pb, Hg, Cd, As were analyzed. It was found that Cd, Hg, Pb accumulated in indoor dust in different degrees with a significant seasonal variation. The geometric means of Pb, Cd, Hg, As concentrations were 63.12 microg x g(-1), 1.67 microg x g(-1), 0.06 microg x g(-1), 0.22 microg x g(-1) in summer and 117.40 microg x g(-1), 4.52 microg x g(-1), 0.95 microg x g(-1), 0.88 microg x g(-1) in winter, respectively. Geo-accumulation indexes calculated for each metal showed a severe contamination of Pb and Cd in indoor surface dusts. The results of exposure and health risk assessment of target substances displayed that the oral intake of dust metals was much higher than that of dermal pathways for children. However, no obvious carcinogenic and non-carcinogenic risks were found for all metals. The Pb, against other species, had the highest non-carcinogenic risk to children, Hazard Index of which was 0.12. Therefore, the health risk of Ph in indoor dust should raise the concern.

Objective: To evaluate the beneficial effects of application of a self-designed reciprocating gait orthosis (RGO) combined with comprehensive rehabilitation training on bladder and bowel function in paraplegic patients sustaining spinal cord injuries (SCI)., Methods: Twelve paraplegic patients with complete spinal cord injury at the levels between T(4) and L(1) received the RGO with a comprehensive rehabilitation exercise program carried out before and after fixing. Cold water and colon excretion tests were performed before and 3 months after application of the RGO, and the bladder volume, residue bladder volume, and bladder and bowel pressures were measured in these patients., Results: The 12 paraplegic patients all showed positive results in cold water test before and after RGO application. Before RGO application, 11 of these patients were positive for urine bacteria and only 1 patient was still positive 3 months after the application. The bladder volume and bowel pressure of the patients were significantly increased (P<0.05), while the residue volume and pressure of the bladder were significantly reduced 3 months after RGO application (P<0.05)., Conclusion: RGO combined with comprehensive rehabilitation training can effectively improve the bladder and bowel function and the quality of life of patients with complete spinal cord injury, suggesting much clinical value for its extensive application.

This paper aims to describe the current situation of the work injury rehabilitation system in China with its drawbacks, especially relating to the employment services for workers with injuries and bringing up the topic of the need for more work to attempt to construct a modern work injury occupational rehabilitation system: perfecting the administration mechanism of policy, establishing an occupational rehabilitation pattern with Chinese characteristics, establishing the socialization service network as the core of occupational rehabilitation and establishing a practical professional team and academic communication platform. These creative thoughts may shed light on the development of the work injury rehabilitation system as well as the return to work for workers with injuries in China.