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Introduction: In order to solve the inhibition of alkaline environment on plants growth at the initial stage of Eco-restoration of vegetation concrete technology, introducing AMF into vegetation concrete substrate is an effective solution. Methods: In this study, Glomus mosseae (GM), Glomus intraradices (GI) and a mixture of two AMF (MI) were used as exogenous inoculation agents. Festuca elata and Cassia glauca were selected as host plants to explore the relationship between the physiological characteristics of plants and the content of substrate cement under exogenous inoculation of AMF. Results: The experiment showed that, for festuca elata, the maximum mycorrhizal infection rates of inoculation with GM, MI were when the cement contents ranged 5-8% and that of GI inoculation was with the cement contents ranging 5-10%. Adversely, for Cassia glauca, substrate cement content had little effect on the root system with the exogenous inoculation of AMF. Compared with CK, the effects of AMF inoculation on the physiological characteristics of the two plants were different. When the cement content was the highest (10% and 8% respectively), AMF could significantly increase(p<0.05) the intercellular CO2 concentration (Ci) of Festuca elata. Moreover, for both plants, single inoculation was more effective than mixed inoculation. When the cement content was relatively low, the physiological characteristics of Cassia glauca were promoted more obviously by the inoculation of GI. At higher cement content level, inoculation of GM had a better effect on the physiological characteristics of the two plants. Conclusion: The results suggest that single inoculation of GM should be selected to promote the growth of Festuca elata and Cassia glauca in higher alkaline environment.

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Background: Soil erosion is a severe problem in the karst watershed, and analysis of soil erosion at the watershed scale is urgently needed. Methods: This study tried to estimate the soil erodibility factor (K-factor) using the Erosion Productivity Impact Calculator (EPIC) nomograph and evaluate the spatial distribution of the predicted K-factor in a karst watershed. Soil properties and K-factors of five land use types (NF: natural mixed forest, CF: cypress forest, EF: economic forest, ST: stone dike terrace, VF: vegetable land) in the Xialaoxi small watershed were compared and key factors affecting erodibility were analyzed. Results: Results showed that (1) The erodibility K-factor was unevenly distributed within different site types and strongly influenced by anthropogenic activities. The soil K-factors of sample sites subjected to frequent human disturbance (ST, VF) were high, ranging from 0.0480-0.0520 t hm2 h/(MJ mm hm2), while the soil K-factors of natural site types (NF, CF, and EF) were low, ranging from 0.0436-0.0448 t hm2 h/(MJ mm hm2). (2) The soil texture in the Xialaoxi watershed was mostly loamy, and that of the agricultural areas frequently disturbed by agricultural practices (ST, VF) was silty loam. (3) Soil carbon fractions were affected by land use types. Soil organic carbon storage of NF and CF had strong spatial heterogeneity. The soil organic carbon (SOC) and labile organic carbon (LOC) of the two were significantly higher than those of the disturbed EF and cultivated land soil. (4) There was a synergistic effect between the soil properties and the K-factor. K was significantly negatively related to sand fractions (2-0.05 mm) and non-capillary porosity, while positively related to silt content (0.05-0.002 mm). Overall, changes in bulk density (BD), total porosity (TP), non-capillary porosity (NCP), texture, and organic matter content caused by natural restoration or anthropogenic disturbance were the main reasons for soil erodibility. Natural care (sealing) and construction of stone dike planting practices were effective ways to reduce soil erosion in small karst watershed areas of western Hubei.

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The electronic properties of monolayer (ML) Ga2O3 and transport properties of ML Ga2O3-based n-type metal-oxide-semiconductor field-effect transistors (MOSFETs) are investigated by first-principles calculations under the framework of density functional theory (DFT) coupled with the nonequilibrium Green's function (NEGF) formalism. The results show that ML Ga2O3 has a quasi-direct band gap of 4.92 eV, and the x- and y-directed electron mobilities are 1210 and 816 cm2 V-1 s-1 at 300 K, respectively, under the full consideration of phonon scattering. The electron-phonon scattering mechanism shows a temperature-dependent behavior, with the acoustic modes dominating below 300 K and optical modes dominating above 300 K. At a gate length of Lg = 5 nm, the on-current of ML Ga2O3 n-MOSFET for high-performance (HP) application is 2890 µA/µm, which is more than those of the most reported two-dimensional (2D) materials. The delay time as well as the power delay product of ML Ga2O3 MOSFETs can meet the demands of the latest International Technology Roadmap for Semiconductors (ITRS) for HP and low-power (LP) applications until Lg is less than 4 and 5 nm, respectively. Through underlap structure and doping optimization strategies, ML Ga2O3 n-MOSFET can further fulfill the ITRS requirements for 1 nm. At last, we compare the performance of the 32-bit arithmetic logic unit (ALU) built on ML Ga2O3 MOSFETs with the recently reported beyond-CMOS devices. Our results indicate that ML Ga2O3 can serve as a promising channel material in the post-silicon era.

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Detection of anthrax biomarker dipicolinic acid (DPA) is of great importance upon the crisis of bioterrorism. Development of fluorescent materials for DPA detection, particularly one that fully depends on single luminescent response, faces the challenge of being susceptible to interferences. The accompanying accuracy problems offer great opportunities for the establishment of more reliable ratiometric analysis method. Herein, a ratiometric fluorescent probe based on terbium functionalized graphitic carbon nitride nanosheets (Tb-g-C3N4NS) is attempted for quantitative detection of DPA to address the distinct function of g-C3N4NS as both carrier and reference fluorophore, which is a so-far unexplored option in fluorescent detection approaches. We achieve the incorporation of Tb3+ into framework of g-C3N4NS by using a simple synthetic strategy comprised of thermal pyrolysis and ultrasonic exfoliation. Combining the reference signal over g-C3N4NS at 440 nm (I440) with the response signal of Tb3+ at 546 nm (I546), concentration of DPA can be easily calculated via its linear correlation with the intensity ratio (I546/I440), giving a precise measurement towards DPA with a detection limit as low as 9.9 nM. Besides enabling an excellent self-calibrating detection of DPA, this work also inspires broader use of g-C3N4NS for relevant process.

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The trivalent europium ion (Eu3+) has garnered a great deal of interest for the design of luminescent materials possessing compound-independent emission bands, strong luminescent intensity, and long emission lifetimes. We herein introduce a synthetic methodology capable of constructing visual luminescent probes from Eu3+ complex-functionalized silica nanocomposites and their Langmuir-Blodgett (LB) films at interfaces. In order to facilitate the coordinative stabilization of Eu3+ over carrier surfaces, silica nanoparticles (nanoSiO2) were pregrafted with terpyridyl (TPy) to make nanoSiO2TPy linkers. Then, a well-designed coordination reaction of nanoSiO2TPy with EuCl3 and 2,6-pyridinedicarboxylic acid (DPA) was carried out at solid-liquid and air-water interfaces, where our desired material (denoted as nanoSiO2TPy@EuDPA) and its corresponding LB film are obtained. The presence of TPy and DPA interacting with Eu3+ plays a key role in regulating the chemical nature of the particle surface, hence giving rise to closely packed nanocomposite arrays in the film. As a result, the improvement in uniformity and stability is achieved alongside the enhancement in emission intensity and lifetime. With such advantageous optical properties, we find them workable as facile, green, and affordable luminescent sensors, by which a range of common toxic anions (Cr2O72-, MnO4-, and PO43-) can be visually and quantitatively recognized. Notably, the LB film-based material could afford a higher Ksv value (1.53 × 105 M-1), a lower detection limit (0.157 µM), and better recyclability than its original powder analogue, showcasing its utility as a more promising candidate for practical use.

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For the on-orbit space zoom camera, the camera focal length is in a constant process of change; accordingly, compared with calibrating other camera intrinsic parameters, calibrating the focal length has a practical significance for the space zoom camera. With the vanishing points obtained from the solar panel of human-made space satellites, this paper introduces a focal length self-calibration method for the on-orbit space zoom camera. First, the geometrical relationship and infinite homography of vanishing points at various camera positions are used to derive the method. To improve the accuracy and robustness performance of this approach, an optimization method is then proposed to nonlinearly optimize the camera focal length. Finally, simulation and real physical experiments demonstrate that the proposed method is flexible and accurate with good anti-noise interference and real-time capacity. The method proposed in this paper makes more realistic sense for a number of important space tasks.