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Lithium iron phosphate (LiFePO4) with an olivine-type structure has garnered great interest due to its electrochemical activity. It is considered one of the most promising cathode materials for lithium-ion batteries because of its high discharge platform, large theoretical capacity, and excellent cycling performance and stability. However, the typical crystal structure of LiFePO4 restricts the formation of efficient electron conduction pathways and hampers the embedding and removal motion of lithium ions, resulting in low electron conductivity and a low ion diffusion rate. The experimental results show that element doping can reduce the activation energy of diffusion, increase the diffusion rate of lithium ions, improve the rate capability of lithium-ion batteries, and contribute to the improvement of its conductivity. In this work, the electronic structure and diffusion mechanism of a S/Co/Mn co-doped LiFePO4 system are systematically studied. The introduction of S, Co, and Mn atoms leads to the formation of impurity bands, resulting in a significant reduction in the bandgap from 3.593 eV to 0.190 eV, which is beneficial for improving the conductivity of LiFePO4. Moreover, the diffusion activation energy of lithium ions decreases from 0.73 eV to 0.34 eV, and the diffusion rate of lithium ions increases from 2.7 × 109 cm/s to 1.0 × 1016 cm/s. These results demonstrate that co-doping of S, Co, and Mn can effectively enhance the conductivity and diffusion rate of lithium ions in LiFePO4, providing a reliable reference for improving the electrochemical performance of lithium iron phosphate.

Spiroorthocarbonates (SOCs) exhibit good shrinkage resistance with ring-opening polymerization initiated by a cationic photoinitiator, with potential application in reducing the volume shrinkage by C=C double bond polymerization on three-dimensional (3D) printing. However, SOCs as an additive dealing with volume shrinkage in 3D printing are rarely reported. Moreover, little progress has been made in the kinetics study on its ring-opening polymerization. In this study, we presented an effective strategy to reduce 3D printing volume shrinkage based on SOCs chemistry and systematically studied the ring-opening photopolymerization kinetics. 3,9-diethyl-3,9-bis(allyloxymethyl)-1,5,7,11-tetraoxastetraoxaspiro undecane (DB-TOSU), one kind of SOCs, was adopted as an expanding monomer. Initiated by cationic photoinitiator with sensitizer under 405 nm LED light, the maximum conversion of DB-TOSU is up to 84%. As a volume-control agent for 3D printing, volume shrinkage reduction is 71.2% when adding DB-TOSU into 3D printing resin based on SOCs chemistry. Moreover, the toughness of resin was enhanced. In the 3D printing application test, DB-TOSU displayed a good application prospect owing to its good compatibility with the printing resin and printing accuracy after volume expansion.

Many previous studies have shown that multiangle, multispectral polarimetric remote sensing can provide valuable information on aerosol microphysical and optical properties, in which the aerosol layer height (ALH) is an important parameter but with less studies, especially in the near-ultraviolet (near-UV) and visible (VIS) wavelength bands. Based on the optimal estimation (OE) theory and information content analysis method, we focus on the sensitivity study of ALH with the synthetic data in the near-UV and VIS wavelength in the range of 410–865 nm, and further to assess the capability of multiangle intensity and polarization measurements for the retrieval of ALH. Unified Linearized Vector Radiative Transfer Model (UNL-VRTM) has been used as the forward model to simulate the intensity and polarized radiance at the top of atmosphere (TOA), as well as the Jacobians of TOA results with respective to corresponding parameters. The degree of freedom for signal (DFS) and a posteriori error are introduced to quantity the information content of ALH from the intensity and polarization measurements, respectively. By assuming the surface type, aerosol model, aerosol loads, prior errors and observation geometries, the sensitivity of ALH has been preliminarily investigated. The sensitivity study results show that the near-UV and polarization measurements are the important source of information content for the aerosol height retrieval in satellite remote sensing.

Aerosols play an important role in climate changes and environmental changes as well as on human health. ADV v3.11, ORAC v4.10, and SU v4.32 was three new versions of Advanced Along-Track Scanning Radiometer (AATSR) aerosol datasets which are published on Climate Change Initiative (CCI). In order to evaluate the accuracy of three AATSR aerosol optical depth (AOD) datasets, and to improve the spatial coverage and accuracy of AATSR AOD dataset, this study completed two works: the first part is validated the accuracy of three AOD datasets; the second part is fused three AATSR AOD datasets based on uncertainty of each dataset. After comparing with AERONET and CARSNET ground-based data over China, results show that the root-mean-square error (RMSE) for ADV v3.11, ORAC v4.10, SU v4.32 and fused AOD are 0.22, 0.17, 0.18, 0.17 respectively.

Fine-mode aerosol usually comes from anthropogenic emissions. The fine-mode aerosol optical depth (AODf) is an important parameter for estimating the particulate matter with an aerodynamic diameter little than 2.5 μm (PM2.5). Compared to the ground-based observations, AODf products from satellite remote sensing have an advantage of high spatial coverage, which is suitable for monitoring the air quality at a regional or global scale. Up to now, AODf products have been released by several sensors, such as the single-angle multi-spectral intensity sensor MODIS and multi-angle multi-spectral polarization sensor POLDER, then what’re the different performances of AODf products from them? In this study, the different spatial resolution AODf products respectively from MODIS latest Collection 6.1 (C6.1, 3 and 10 km) and POLDER latest level 2 version 1.01 (L2, 18 km) were firstly compared with each other in Beijing-Tianjin-Hebei (BTH) domains. Then those products were validated against the ground-based AERosol RObotic NETwork (AERONET) measurements, where has been suffering the severe air pollution since decades ago. The comparison of yearly averaged AODf products between MODIS and POLDER shows a good consistency on the spatial distribution, the higher spatial resolution products of MODIS show more details, both low values of AODf appeared in the northwest area with small population and industry, high values appeared in the southeast area with lots of cities, industries, and large population. However, the whole yearly AODf average values of MODIS are higher than that of POLDER. The results of validation against AERONET show that the accuracy of AODf products at 865 nm from POLDER (R = 0.94, RMSE = 0.05) is high than that at 550 nm of MODIS (3 km: R = 0.69, RMSE = 0.32; 10 km: R = 0.76, RMSE = 0.3). In this study, the performance of different spatial resolutions AODf products retrieved from the intensity (MODIS 3 and 10 km) and polarized sensors (POLDER 18 km) were evaluated. Those results not only have a great significance to provide users amore appropriate choice of the AODf products in the BTH region but also display that the accuracy and spatial resolution of MODIS and POLDER AODf products need to be improved.

This paper evaluates the information content for the retrieval of key aerosol microphysical and surface properties for multispectral single-viewing satellite polarimetric measurements cantered at 410, 443, 555, 670, 865, 1610 and 2250 nm over bright land. To conduct the information content analysis, the synthetic data are simulated by the Unified Linearized Vector Radiative Transfer Model (UNLVTM) with the intensity and polarization together over bare soil surface for various scenarios. Following the optimal estimation theory, a principal component analysis method is employed to reconstruct the multispectral surface reflectance from 410 nm to 2250 nm, and then integrated with a linear one-parametric BPDF model to represent the contribution of polarized surface reflectance, thus further to decouple the surface-atmosphere contribution from the TOA measurements. Focusing on two different aerosol models with the aerosol optical depth equal to 0.8 at 550 nm, the total DFS and DFS component of each retrieval aerosol and surface parameter are analysed. The DFS results show that the key aerosol microphysical properties, such as the fine- and coarse-mode columnar volume concentration, the effective radius and the real part of complex refractive index at 550 nm, could be well retrieved with the surface parameters simultaneously over bare soil surface type. The findings of this study can provide the guidance to the inversion algorithm development over bright surface land by taking full use of the single-viewing satellite polarimetric measurements.

The phase function and polarized phase function are important optical parameters, which describe scattering properties of atmospheric aerosol particles. Polarization of skylight induced by the scattering processes is sensitive to the scattering properties of aerosols. The Stokes parameters I, Q, U and the polarized radiance Lp of skylight measured by the CIMEL dual-polar sun-sky radiometer CE318- DP can be use to retrieve the phase function and polarized phase function, respectively. Two different observation geometries (i.e., the principal plane and almucantar) are preformed by the CE318-DP to detect skylight polarization. Polarization of skylight depends on the illumination and observation geometries. For the same solar zenith angle, retrievals of the phase function and the polarized phase function are still affected by the observation geometry. The performance of the retrieval algorithm for the principal plane and almucantar observation geometries was assessed by the numerical experiments at two typical high and low sun’s positions (i.e. solar zenith angles are equal to 45° and 65°). Comparing the results for the principal plane and almucantar geometries, it is recommended to utilize the principal plane observations to retrieve the phase function when the solar zenith angle is small. The Stokes parameter U and the polarized radiance Lp from the almucantar observations are suggested to retrieve the polarized phase function, especially for short wavelength channels (e.g., 440 and 500 nm).

The halophyte Thellungiella salsuginea is a new model plants due to its small genome size, short life cycle, and copious seed production. Although T. salsuginea shares a high sequence identity with its close relative Arabidopsis thaliana, it shows a greater tolerance to salinity, drought, freezing, heat, and cold. To elucidate the mechanism of abiotic stress resistance in T. salsuginea, we characterized its cytosolic Apx1 gene (TsApx1) and established A. thaliana transgenic lines overexpressing TsApx1. Under 300 mM NaCl, the content of H2O2, malondialdehyde, and proline were lower and the activities of superoxide dismutase, catalase, glutathione peroxidase, and ascorbate peroxidase were all higher in the transgenic plants overexpressing TsApx1 (35S:TsApx1-GFP) than in the wild-type plants. The atapx1 mutant plants of A. thaliana had a NaCl/mannitol-sensitive phenotype. The ectopic expression of TsApx1 in the atapx1 mutant effectively remedied the phenotype. These results suggest that TsApx1 plays an important role in scavenging reactive oxygen species in the cytoplasm under salinity or drought. Although TsApx1 in T. salsuginea was constantly expressed at a high level, this gene was clearly inducible. In summary, the high constitutive expression and rapid induction of TsApx1 may contribute to the tolerance to abiotic stresses in T. salsuginea.

The structural and magnetic properties of as-deposited and 550 degree Celsius annealed Fe-C granular films were investigated. Findings reveal that the as-deposited samples are composed of amorphous Fe granules dispersed in an amorphous C matrix.

We study the magnetotransport property of a (In, Zn)As/InAs p-n junction and observe a breakdown behavior in the reverse bias region. This breakdown behavior can be attributed to two different electronic processes: the trap-assisted tunneling at moderate reverse voltage and the impact ionization at high reverse voltage. The former gives rise to a positive magnetoresistance, and a maximum of 226% is obtained at room temperature. The latter induces a very large positive magnetoresistance and its maximum of 428% is observed at a reverse voltage of 1.32V. [ABSTRACT FROM AUTHOR]

FeNiN thin films with good soft magnetic properties were synthesized on Si (1?0?0) substrates at 473?K by RF magnetron sputtering; all the films have a thickness of around 500?nm. The dependence of phase structure and magnetic properties on nickel concentrations and RF power were systematically investigated. With increasing nickel contents from XNi= 5.0% to XNi= 65.5%, FeNiN thin films deposited at turn from a main bcc ?-(Fe,Ni) phase coexisting with ?'-phase to fcc ?-(FeNi3)4N phase. With the RF power larger than 160?W, the samples deposited at all show clear reproducible striped domains at the films' surfaces, which is explained by the high enough perpendicular anisotropy and the small stress in the film. A completely ordered structure of (FeNi)N0.0324-phase forms at PW= 300?W. The FeNiN thin films prepared at different RF power show smooth surfaces and good soft magnetic properties compared with corresponding FeN compounds. The optimum soft magnetic properties with MSof ? 1900?emu?cm?3, HCof ?1?Oe are obtained at and PW= 300?W at 473?K. [ABSTRACT FROM AUTHOR]

Polycrystalline Fe3O4/Al bilayers with Al underlayers (ULs) of different thicknesses were fabricated using facing-target reactive sputtering. Structure analyses revealed that Al ULs improve the crystallinity and reduce the thickness of the Fe3O4amorphous initial layer. Room-temperature magnetization of the Fe3O4films with 30?nm thick Al ULs is ?450?emu?cm?3at 50?kOe fields, which is much larger than that of the polycrystalline Fe3O4monolayer deposited under the same conditions. The field-cooled hysteresis loop of Fe3O4films on the 30?nm thick Al layer shows a 50?Oe exchange bias field at 5?K, much smaller than 256?Oe detected in polycrystalline Fe3O4monolayer and the exchange bias fields in the samples with and without 30?nm Al UL decrease with the increasing temperature. The enhancement of the magnetization and the sharp decrease in the exchange bias field observed in the Fe3O4films with Al ULs can be attributed to the decoupling of the antiferromagnetic domains and the thickness reduction of the amorphous Fe-O layers between the polycrystalline Fe3O4films and the Al ULs. [ABSTRACT FROM AUTHOR]

We report on infrared (IR) spectromicroscopy of the electronic excitations in nanometer-thick accumulation layers in field-effect transistor (FET) devices based on poly(3-hexylthiophene). IR data allows us to explore the charge injection landscape and uncovers the critical role of the gate insulator in defining relevant length scales. This work demonstrates the unique potential of IR spectroscopy for the investigation of physical phenomena at the nanoscale occurring at the semiconductor−insulator interface in FET devices. [ABSTRACT FROM AUTHOR]

The electronic structure and optical properties of pure and Nb-doped TiO2 with anatase structure were calculated using local-density approximation based on the density-functional theory. For the undoped TiO2, the Fermi level locates in the band gap between the conduction band and valence band, while it moves into the conduction band and shows metal-like characteristic after Nb atom was introduced into the TiO2 supercell. The optical absorption coefficients for both compounds are very small in the visible light range. Our calculations provide electronic structure evidence that the Nb-doped anatase TiO2 is a new type transparent conducing metal. [ABSTRACT FROM AUTHOR]

A kind of circularly-polarised radial line slot antenna for high-power microwave application is proposed by contriving a kind of radial line slow-wave structure, an improved circularly-polarised radiator unit and a reflection cancelling slot. An antenna prototype with a length of 12 cm and an aperture diameter of 54 cm is designed, which has a gain of 29.0 dBi and an axial ratio of 1.12 at 9.42 GHz. The highpower experiment proves that this antenna has a power-handling capacity of more than 600 MW. [ABSTRACT FROM AUTHOR]

The electronic structure and optical properties of pure and Nb-doped TiO2 with anatase structure were calculated using local-density approximation based on the density-functional theory. For the undoped TiO2, the Fermi level locates in the band gap between the conduction band and valence band, while it moves into the conduction band and shows metal-like characteristic after Nb atom was introduced into the TiO2 supercell. The optical absorption coefficients for both compounds are very small in the visible light range. Our calculations provide electronic structure evidence that the Nb-doped anatase TiO2 is a new type transparent conducing metal. [ABSTRACT FROM AUTHOR]

High spin states in 108Ag have been studied via in-beam γ spectroscopy techniques using the 104Ru(7Li, 3n) reaction. The previously known level scheme has been extended, and a new band structure has been established. The configurations have been tentatively assigned to all observed rotational bands. The signature splitting behavior of the p g9/2 ⊗ νg7/2 band has been discussed and interpreted as a change in shape from near-oblate to prolate. A systematic study of the nearly degenerate negative-parity bands in the A ~ 110 mass region has been performed and it is found that the yrast band in 108Ag and its side band show different behaviors with those expected from a pair of chiral bands. [ABSTRACT FROM AUTHOR]