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There are detrimental effects of vehicle exhaust pollutants such as particulate matter (PM) and nitrogen oxides (NOx) on the environment and human health. In order to enhance the performance of woody LaCo0.7Fe0.3O3 perovskite-type catalysts for purifying PM and NOx, non-thermal plasma (NTP) generated by dielectric barrier discharge (DBD) was used as an assisted preparation method in this paper. The physicochemical properties of LaCo0.7Fe0.3O3 perovskite-type catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), and N2 adsorption–desorption. The LaCo0.7Fe0.3O3 perovskite-type catalysts prepared with and without NTP assisted method were tested and compared by a simulated test bench. The experimental results indicate that the purification efficiency of LaCo0.7Fe0.3O3 perovskite-type catalysts for PM and NOx with NTP assisted method is significantly higher than LaCo0.7Fe0.3O3 perovskite-type catalysts without NTP assisted method. When the input voltage and frequency are 15 kV and 10 kHz, the precursor of the catalyst sample is pretreated for 90 min, and the woody LaCo0.7Fe0.3O3 perovskite-type catalyst obtained shows the highest PM and NOx purification efficiency, within the range of approximately 96% and 50%, respectively. The PM and NOx purification mechanisms were deduced based on the experimental findings. [ABSTRACT FROM AUTHOR]

This paper mainly studies a detection method of dynamic load altering attacks (D‐LAAs) in smart grids. First, communication factors are considered, and a smart grid discrete system model under D‐LAA attack is established. Second, for closed‐loop D‐LAAs, an adaptive fading Kalman filter (AFKF) is designed to estimate the states of smart grids with Gaussian noise in real time, and a Euclidean distance ratio detection algorithm based on AFKF is proposed to detect D‐LAAs. Moreover, the proposed detection algorithm can identify D‐LAAs even in the presence of noise in the measurement data, significantly enhancing the speed of attack detection. Finally, take a smart grid with three generators and six buses as an example. Its feasibility and effectiveness of the Euclidean distance ratio detection algorithm are verified by simulations. The simulations are carried out through the real‐time hardware‐in‐the‐loop simulation platform, which is mainly composed of StarSim and multi‐tasking devices. [ABSTRACT FROM AUTHOR]

In this paper, LaCoO3 porous perovskite was synthesized using wood powder template combined with sol–gel process, while LaCoO3 prepared by traditional sol–gel method was used as a comparison. The catalysts prepared by different methods were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), N2 adsorption–desorption, and the particulate matter (PM) trapping and catalytic oxidation tests were carried out by engine bench test and thermogravimetric analyzer (TGA). The results showed that the porous LaCoO3 successfully replicated the structural features of wood powder from macroscopic to tracheid, forming a porous structure. Porous LaCoO3 exhibits better catalytic activity than powdered LaCoO3 with similar specific surface area, this can be attributed to the porous structure of LaCoO3, which increases the contact area and the number of contact points between PM and catalyst. [ABSTRACT FROM AUTHOR]

This paper develops a nonlinear shear-strength reduction technique for analyzing the stability of uniform slopes with the general nonlinear failure criterion. To incorporate the nonlinear power-law failure criterion into the finite-element slope stability analysis with the shear-strength reduction method (SSR-FEM), a general tangential approach is employed to obtain the instantaneous cohesive strength and internal friction angle from the power-law failure criterion iteratively. Therefore, the shear strength of the power-law criterion can be expressed by the instantaneous Mohr–Coulomb (MC) parameters related to stress within the slope soil. By this way, it is possible to use the linear MC failure criterion for the nonlinear slope stability analysis based on the conventional SSR-FEM. The proposed approach is applied to three typical examples including a homogenous 2D slope, a homogenous 3D slope, and a high rockfill embankment slope. The results show that the nonlinear shear-strength reduction technique presented in this paper can guarantee the accuracy and feasibility to determine the factor of safety (FOS) and provide an alternative way for stability analysis of simple uniform cohesive slopes with a general power-law criterion. [ABSTRACT FROM AUTHOR]

This paper presents a set of stability charts for the stability assessment of rock slopes that satisfy the Hoek–Brown (HB) criterion under various seismic loading conditions. The nonlinear Hoek–Brown strength reduction technique is used to conduct pseudostatic stability analysis of rock slopes subjected to horizontal seismic excitation. Based on an extensive parametric study, first, a set of stability charts with a slope angle of β = 45° under static and pseudostatic conditions are proposed by using ABAQUS 6.10 software. Second, the slope angle weighting factor (fβ) and the seismic weighting factor (fkh) are adopted to characterize the influence of slope angle (β) and horizontal seismic acceleration coefficient (kh) on the rock slope stability. Finally, the reliability of the proposed charts was validated by three typical examples and two case studies, and the results show that the values of the factor of safety (FOS) obtained from the proposed charts are consistent with the values from other methods. The proposed charts provide an efficient and convenient way to determine the FOS of rock slopes directly from the rock mass properties (γ and σci), the HB parameters (mi and GSI), the slope geometry (H and β), and the horizontal seismic coefficients (kh). [ABSTRACT FROM AUTHOR]

This paper uses the modified strength reduction finite element method to propose stability charts for pseudostatic stability analysis of three-dimensional (3D) homogeneous soil slopes subjected to seismic excitation. These charts are developed in a wide range of input parameters for purely cohesive slopes and cohesive-frictional slopes, respectively. Effect of the horizontal seismic load is approximately considered using the quasistatic approach. The stability charts allow to determine the factor of safety without any iterative procedure and identify the corresponding critical slope failure mechanism. A slope example is employed to illustrate the application and reliability of these stability charts. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) fluorescence imaging is an important imaging technology in deep-tissue biomedical imaging and related researches, due to the low absorption and scattering of NIR excitation and/or emission in biological tissues. Laser scanning confocal microscopy (LSCM) plays a significant role in the family of fluorescence microscopy. Due to the introduction of pinhole, it can provide images with optical sectioning, high signal-to-noise ratio and better spatial resolution. In this study, in order to combine the advantages of these two techniques, we set up a fluorescence microscopic imaging system, which can be named as NIR-LSCM. The system was based on a commercially available confocal microscope, utilizing a NIR laser for excitation and a NIR sensitive detector for signal collection. In addition, NIR fluorescent nanoparticles (NPs) were prepared, and utilized for fluorescence imaging of the ear and brain of living mice based on the NIR-LSCM system. The structure of blood vessels at certain depth could be visualized clearly, because of the high-resolution and large-depth imaging capability of NIR-LSCM. [ABSTRACT FROM AUTHOR]

Microscopic images of tissue sections from mice injected with PbS@CdS@SiO SB 2 sb @F-127 NPs (row 2 and row 4) and mice injected with PBS (1×) solution (row 1 and row 3) for 24 h (row 1 and row 2) and 4 weeks (row 3 and row 4). B 2018 b , I 28 i , 1703451 DOI: 10.1002/adfm.201703451 The originally published article contains an error for the H&E microscopic images of histopathological sections (Figures S18 in Supporting information). Ultrastable and Biocompatible NIR-II Quantum Dots for Functional Bioimaging. [Extracted from the article]

As a kind of novel porous ceramics, wood ceramics can be used for filtration, friction, energy storage and electrode materials, etc. In current work, the carbon based wood ceramics (C WCMs) was prepared using pine wood powder and phenolic resin as starting materials. The effects of filling rate of wood powder and resin concentration on pore characteristics and properties of C WCMs were characterized and analyzed with different techniques. Furthermore, the association among porosity of C WCMs, filling rate of wood powder and resin concentration was explored with multiple regression model. The results showed that: increasing the resin concentration and the filling rate of wood powder can improve the mechanical properties of C WCMs, but reduce the porosity and air permeability; when resin concentration is more than 50%, a large amount of caking will appear in the C WCMs, causing internal defects; changing the filling rate under a certain resin concentration can obtain the C WCMs with better pore structure; the porosity of C WCMs has a good linear relationship with resin concentration and filling rate, under the condition that sintering process and the size of wood powder are determined. [ABSTRACT FROM AUTHOR]

Vacuolar invertase is involved in sugar metabolism and plays a crucial role in plant growth and development, thus regulating seed size. However, information linking vacuolar invertase and seed size in rice is limited. Here we characterized a small grain mutant sg2 (grain size on chromosome 2) that showed a reduced in grain size and 1000-grain weight compared to the wild type. Map-based cloning and genetic complementation showed that OsINV3 is responsible for the observed phenotype. Loss-of-function of OsINV3 resulted in grains of smaller size when compared to the wild type, while overexpression showed increased grain size. We also obtained a T-DNA insertion mutant of OsINV2, which is a homolog of OsINV3 and generated double knockout (KO) mutants of OsINV2 and OsINV3 using CRISPR/Cas9. Genetic data showed that OsINV2, that has no effect on grain size by itself, reduces grain length and width in the absence of OsINV3. Altered sugar content with increased sucrose and decreased hexose levels, as well as changes vacuolar invertase activities and starch constitution in INV3KO, INV2KO, INV3KOINV2KO mutants indicate that OsINV2 and OsINV3 affect sucrose metabolism in sink organs. In summary, we identified OsINV3 as a positive regulator of grain size in rice, and while OsINV2 has no function on grain size by itself. In the absence of OsINV3, it is possible to detect a role of OsINV2 in the regulation of grain size. Both OsINV3 and OsINV2 are involved in sucrose metabolism, and thus regulate grain size. Our findings increase our understanding of the role of OsINV3 and its homolog, OsINV2, in grain size development and also suggest a potential strategy to improve grain yield in rice. [ABSTRACT FROM AUTHOR]

The reuse of rubber in concrete results in two major opposing effects: an enhancement in durability and a reduction in mechanical strength. In order to strengthen the mechanical properties of rubber concrete, steel fibers were added in this research. The compressive strength, the four-point bending strength, the mass loss rate, and the relative dynamic elastic modulus of steel fiber reinforced rubber concrete, subjected to cyclic freezing and thawing, were tested. The effects of the content of steel fibers on the freeze–thaw resistance are discussed. The microstructure damage was captured and analyzed by Industrial Computed Tomography (ICT) scanning. Results show that the addition of 2.0% steel fibers can increase the compressive strength of rubber concrete by 26.6% if there is no freeze–thaw effect, but the strengthening effect disappears when subjected to cyclic freeze–thaw. The enhancement of steel fibers on the four-point bending strength is effective under cyclic freeze–thaw. The effect of steel fibers is positive on the mass loss rate but negative on the relative dynamic elastic modulus. [ABSTRACT FROM AUTHOR]

Frost damage of concrete has significant effects on the safety and durability of concrete structures in cold regions, and the concrete structures after repair and reinforcement are still threatened by cyclic freezing and thawing. In this study, the new-to-old concrete interface was reinforced by steel bar. The shear strength of the new-to-old concrete interface was tested after the new-to-old combination was subjected to cyclic freeze–thaw. The effects of the diameter of the steel bar, the compressive strength of new concrete, the number of freeze–thaw cycles and the freezing temperatures on the shear properties of new-to-old concrete interface were studied. The results showed that, in a certain range, the shear strength of the interface was proportional to the diameter of the steel bar and the strength of the new concrete. Meanwhile, the shear strength of the reinforced interface decreased with the decreasing of the freezing temperature and the increasing of the number of freeze–thaw cycles. [ABSTRACT FROM AUTHOR]

Second near-infrared (NIR-II, 1000-1700 nm) fluorescence bioimaging has attracted tremendous scientific interest and already been used in many biomedical studies. However, reports on organic NIR-II fluorescent probes for in vivo photoinduced imaging and simultaneous therapy, as well as the long-term tracing of specific biological objects, are still very rare. Herein we designed a single-molecular and NIR-II-emissive theranostic system by encapsulating a kind of aggregation-induced emission luminogen (AIEgen, named BPN-BBTD) with amphiphilic polymer. The ultra-stable BPN-BBTD nanoparticles were employed for the NIR-II fluorescence imaging and photothermal therapy of bladder tumors in vivo. The 785 nm excitation triggered photothermal therapy could completely eradicate the subcutaneous tumor and inhibit the growth of orthotopic tumors. Furthermore, BPN-BBTD nanoparticles were capable of monitoring subcutaneous and orthotopic tumors for a long time (32 days). Single-molecular and NIR-II-emitted aggregation-induced emission nanoparticles hold potential for the diagnosis, precise treatment, and metastasis monitoring of tumors in the future.

Currently, a serious problem obstructing the large-scale clinical applications of fluorescence technique is the shallow penetration depth. Two-photon fluorescence microscopic imaging with excitation in the longer-wavelength near-infrared (NIR) region (>1100 nm) and emission in the NIR-I region (650-950 nm) is a good choice to realize deep-tissue and high-resolution imaging. Here, we report ultradeep two-photon fluorescence bioimaging with 1300 nm NIR-II excitation and NIR-I emission (peak ∼810 nm) based on a NIR aggregation-induced emission luminogen (AIEgen). The crab-shaped AIEgen possesses a planar core structure and several twisting phenyl/naphthyl rotators, affording both high fluorescence quantum yield and efficient two-photon activity. The organic AIE dots show high stability, good biocompatibility, and a large two-photon absorption cross section of 1.22 × 10 3 GM. Under 1300 nm NIR-II excitation, in vivo two-photon fluorescence microscopic imaging helps to reconstruct the 3D vasculature with a high spatial resolution of sub-3.5 μm beyond the white matter (>840 μm) and even to the hippocampus (>960 μm) and visualize small vessels of ∼5 μm as deep as 1065 μm in mouse brain, which is among the largest penetration depths and best spatial resolution of in vivo two-photon imaging. Rational comparison with the AIE dots manifests that two-photon imaging outperforms the one-photon mode for high-resolution deep imaging. This work will inspire more sight and insight into the development of efficient NIR fluorophores for deep-tissue biomedical imaging.