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Infrared detectors have broad application prospects in the fields of detection and communication. Using ideal materials and good device structure is crucial for achieving high-performance infrared detectors. Here, we utilized black phosphorus (BP) and single-walled carbon nanotube (SWCNT) films to construct a vertical van der Waals heterostructure, resulting in high-performance photovoltaic infrared detectors. In the device, a strong built-in electric field was formed in the heterojunction with a favored energy-band matching between the BP and the SWCNT, which caused a good photovoltaic effect. The fabricated devices exhibited a diode-like rectification behavior in the dark, which had a high rectification ratio up to a magnitude of 104 and a low ideal factor of 1.4. Under 1550 nm wavelength illumination, the 2D BP/SWCNT film photodetector demonstrated an open-circuit voltage of 0.34 V, a large external power conversion efficiency (η) of 7.5% and a high specific detectivity (D*) of 3.1 × 109 Jones. This external η was the highest among those for the photovoltaic devices fabricated with the SWCNTs or the heterostructures based on 2D materials and the obtained D* was also higher than those for most of the infrared detectors based on 2D materials or carbon materials. This work showcases the application potential of BP and SWCNTs in the detection field. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) black phosphorus (BP) is considered an ideal building block for field-effect transistors (FETs) owing to its unique structure and intriguing properties. To achieve high-performance BP-FETs, it is essential to establish a reliable and low-resistance contact between the BP and the electrodes. In this study, we employed a localized Joule heating method to improve the contact between the 2D BP and gold electrodes, resulting in enhanced BP-FET performance. Upon applying a sufficiently large source–drain voltage, the zero-bias conductance of the device increased by approximately five orders of magnitude, and the linearity of the current–voltage curves was also enhanced. This contact improvement can be attributed to the formation of gold phosphide at the interface of the BP and the gold electrodes owing to current-generated localized Joule heat. The fabricated BP-FET demonstrated a high on/off ratio of 4850 and an on-state conductance per unit channel width of 1.25 μS μm−1, significantly surpassing those of the BP-FETs without electrical annealing. These findings offer a method to achieve a low-resistance BP/metal contact for developing high-performance BP-based electronic devices. [ABSTRACT FROM AUTHOR]

Introduction:W. confusa has been known to cause various human infections. It is naturally resistant to vancomycin and is difficult to identify using traditional methods, which may lead to misidentification and delay treatment.Case Presentation: We present a case of a 42-year-old male patient with gastrointestinal bleeding and coronary heart disease who developed sepsis caused by Weissella confusa. The patient's blood cultures showed the presence of gram-positive coccobacilli, later identified as W. confusa through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing revealed that W. confusa had low minimum inhibitory concentrations (MICs) for some drugs (eg, ampicillin) and higher MICs for others (eg, cefotaxime). Empirical treatment with vancomycin was initially started, but after obtaining the identification and susceptibility results, the treatment was switched to meropenem combined with daptomycin, resulting in a successful outcome.Conclusion:Weissella confusa bacteremia is relatively rare, and accurate pathogenic diagnosis is essential for effective clinical treatment. [ABSTRACT FROM AUTHOR]

Three vanadium-based catalysts were used to remove high concentrations of nitrogen oxides, and the catalysts' performance of de-NOx and anti-H2O under the high concentrations of NOx were investigated. The V-Mo-W/TiO2 catalysts were tested under 1500 mL/min gas flow (GHSV = 500 h−1, 2.4% NO2, 4.78% NH3, 13% O2, 4% H2O, 5% CO2) and characterized by BET, SEM, EDS, XRD, XPS, H2-TPR, and NH3-TPD; then, their physical and chemical properties were analyzed. The results showed that under the influence of H2O, the NOx conversion of the V-Mo-W/TiO2 catalysts remained above 97% at 200–280 °C indicating that the catalysts had high catalytic activity and strong water resistance. The analysis of the characterization results showed that the larger specific surface area of the catalyst, the higher acid content, stronger redox ability, and higher V4+ and V3+ content were the reasons for the high NOx conversion. The surface area decreased and the microstructure become smoother after the reaction, which may be caused by thermal sintering, but the overall morphology did not change. Comparing the H2-TPR and NH3-TPD of V1.6Mo1.7W1.8/TiO2 before and after NH3-SCR reaction, it was found that the reduction peak and the intensity of the acid sites of the sample had not changed, which indicated that the catalyst had good anti-sintering performance and a long lifetime. This is significant for followup long-term engineering application experiments. [ABSTRACT FROM AUTHOR]

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The flexible piezoresistive sensors have versatile applications for healthcare. The fabrication procedures of these sensors are generally costly, complex, and environmentally unfriendly. Herein, we use L-cystine as the green reductant and templating agent to prepare 3D reduced graphene oxide (rGO) aerogel, and polyvinyl chloride tape as the substrates to encapsulate the aerogel for making the piezoresistive sensor. The sensor shows good linearity of resistance to logarithmic pressure value in a wide range of 170.4 kPa to 2.4 MPa, and it is capable to monitor the wrist pulse and human motion. Sensors fabricated by this facile and economical method have great potential application in electronic skin. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Deactivation of V 2 O 5 /TiO 2 catalysts during selective catalytic reduction (SCR) of NO by NH 3 , especially the alkali metal-induced deactivation, has received much attention in recent years. Many researches have been done using different poisoning methods to understand the deactivation behavior of catalyst in industry, but the results were somewhat inconsistent. This work compares the poisoning methods – wet impregnation, solid diffusion and vapor deposition from the viewpoint of deactivation rate and deactivation mechanism using V 2 O 5 –WO 3 /TiO 2 as the catalyst and KCl as the poisoning substance. Results indicate that deactivation extent of the catalyst depends not only on the quantity of KCl but also on how KCl is introduced to the catalyst, following an order of vapor deposition ≫ solid diffusion > wet impregnation. The presence of V 2 O 3 species due to interaction of K with oxygen in vanadium oxides is mainly responsible for the catalyst deactivation by wet impregnation. The formation of K 2 S 2 O 7 –V 2 O 5 eutectic is mainly responsible for the catalyst deactivation by solid diffusion at a higher K/V ratio and vapor deposition due to the significant decrease of NH 3 adsorption and increase in NH 3 oxidation activity. [ABSTRACT FROM AUTHOR]

Recoveryof vanadium from various sources is important to the environmentand industry. This work investigates vanadium leaching from a spentselective catalytic reduction catalyst by sulfuric acid at atmosphericpressure. It includes the effects of stirring speed, solid to liquidratio, temperature, and sulfuric acid concentration on the vanadiumrecovery yield. The results show that the vanadium recovery yieldincreases with increases in temperature, sulfuric acid concentration,and leaching time and decreases with an increase in solid to liquidratio. The leaching data can not be described well by kinetic modelscommonly adopted for similar processes in the literature. The Avramiequation, originally developed for crystallization, is found to bemost suitable. The leaching is controlled by diffusion in the solidwith an activation energy of 5.90 kJ/mol. [ABSTRACT FROM AUTHOR]

High-performance tracking trace amounts of NO2 with gas sensors could be helpful in protecting human health since high levels of NO2 may increase the risk of developing acute exacerbation of chronic obstructive pulmonary disease. Among various gas sensors, Graphene-based sensors have attracted broad attention due to their sensitivity, particularly with the addition of noble metals (e.g., Ag). Nevertheless, the internal mechanism of improving the gas sensing behavior through doping Ag is still unclear. Herein, the impact of Ag doping on the sensing properties of Graphene-based sensors is systematically analyzed via first principles. Based on the density-functional theory (DFT), the adsorption behavior of specific gases (NO2, NH3, H2O, CO2, CH4, and C2H6) on Ag-doped Graphene (Ag–Gr) is calculated and compared. It is found that NO2 shows the strongest interaction and largest Mulliken charge transfer to Ag–Gr among these studied gases, which may directly result in the highest sensitivity toward NO2 for the Ag–Gr-based gas sensor. [ABSTRACT FROM AUTHOR]

To handle nonlinear filtering problems with networked sensors in a distributed manner, a novel distributed hybrid consensus–based square-root cubature quadrature information filter is proposed. The proposed hybrid consensus–based square-root cubature quadrature information filter exploits fifth-order spherical simplex-radial quadrature rule to tackle system nonlinearities and incorporates a novel measurement update strategy into the hybrid consensus filtering framework, which takes the predicted measurement error into account and hence produces more accurate estimates. In addition, the proposed hybrid consensus–based square-root cubature quadrature information filter inherits the complementary positive features of both consensus on information and consensus on measurements methods and avoids sensitive matrix operations such as square-root decompositions and inversion of covariances, which is beneficial for numerical stability. Stability analysis with respect to consensus, convergence, and consistency for the proposed hybrid consensus–based square-root cubature quadrature information filter is also developed. The effectiveness of the proposed hybrid consensus–based square-root cubature quadrature information filter is validated through a maneuvering target tracking scenario. The simulation results show that the proposed hybrid consensus–based square-root cubature quadrature information filter outperforms the existing algorithms at the expense of a slight increase in computational cost. [ABSTRACT FROM AUTHOR]