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Ni catalysts decorated with trace Rh supported on γ-Al2O3 were prepared by the co-impregnation method. To obtain the Ni–Rh nanoparticles with different nanostructures and chemical compositions, bimetallic catalysts with varied Ni/Rh molar ratios were prepared. For comparison, monometallic Ni/γ-Al2O3 and Rh/γ-Al2O3 catalysts were also prepared by the impregnation method. The selective gas phase catalytic hydrodechlorination of 1,2-dichloroethane to ethylene was used to evaluate catalytic performances of the catalysts. The catalysts were characterized by X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, H2 temperature-programmed reduction, transmission electron microscopy–energy-dispersive X-ray, and CO chemisorption. It was found that the introduction of Rh to Ni catalyst facilitated the generation of spillover hydrogen which could enhance the ability of the Ni catalyst for H2 activation. In bimetallic catalysts, there was an intimate interaction between Ni and Rh, and isolated Rh sites were formed due to the dilution effect of Ni. Accordingly, compared with the monometallic Ni catalyst for gas phase catalytic hydrodechlorination of 1,2-dichloroethane, the bimetallic Ni–Rh(800)/γ-Al2O3 catalyst exhibited markedly higher 1,2-dichloroethane conversion (37%) and comparable selectivity to ethylene (95%). The findings in this study indicate that Ni–Rh/γ-Al2O3 with trace Rh can be used as a promising catalyst for highly effective and selective catalytic hydrodechlorination of chlorinated hydrocarbons. [ABSTRACT FROM AUTHOR]

Highly active, low-cost, and stable photocatalysts are the key point for the development of photocatalysis technology, which is one of the most promising advanced approaches to a greener future. As a nonmetallic polymer with high performance, graphitic carbon nitride (g-C3N4) has a notable effect on photocatalytic CO2 reduction. However, the narrow light absorption limits its photocatalytic efficiency. In this work, we prepared red g-C3N4 with the oxygen bridge structure (CSCN) using a grinding thermal polymerization method. The oxygen bridge structure provides more active sites, broadens the light absorption range, and improves the charge separation efficiency. Benefiting from the combined above advantages, CSCN exhibited a rate of photocatalytic reduction of CO2 to CO of 28.5 μmol g−1 h−1. This work proposes a way to enhance the light absorption efficiency and CO2 reduction properties of g-C3N4. [ABSTRACT FROM AUTHOR]

WDR proteins in plants regulate multiple aspects of plant growth and development, as well as plant responses to environmental stimuli. Here, we report the identification of AIW1 (ABA-induced WD40-repeat 1) and AIW2 as novel regulators of salt responses in Arabidopsis. RT-PCR results show that the expression of AIW1 and AIW2 were induced by ABA. Transfection assays in protoplasts show that AIW1 and AIW2 were nucleus proteins and functioned as transcription repressors. When overexpressed in Arabidopsis, AIW1 promoted root elongation, and reduced seedlings sensitivity to ABA. On the other hand, aiw1 aiw2 double mutants showed an increased sensitivity to ABA in seed germination assays. In addition, salt tolerance was reduced in the 35S:AIW1 transgenic plants in root elongation assays. Taken together, our results suggest that AIW1 and AIW2 are ABA-induced plant specific WD40 repeat-containing transcription repressors, and AIW1 and AIW2 function redundantly to regulate ABA and salt responses in Arabidopsis. [ABSTRACT FROM AUTHOR]

EAR motif-containing proteins are able to repress gene expression, therefore play important roles in regulating plants growth and development, plant response to environmental stimuli, as well as plant hormone signal transduction. ABA is a plant hormone that regulates abiotic stress tolerance in plants via signal transduction. ABA signaling via the PYR1/PYLs/RCARs receptors, the PP2Cs phosphatases, and SnRK2s protein kinases activates the ABF/AREB/ABI5-type bZIP transcription factors, resulting in the activation/repression of ABA response genes. However, functions of many ABA response genes remained largely unknown. We report here the identification of the ABA-responsive gene SlEAD1 (Solanum lycopersicum EAR motif-containing ABA down-regulated 1) as a novel EAR motif-containing transcription repressor gene in tomato. We found that the expression of SlEAD1 was down-regulated by ABA treatment, and SlEAD1 repressed reporter gene expression in transfected protoplasts. By using CRISPR gene editing, we generated transgene-free slead1 mutants and found that the mutants produced short roots. By using seed germination and root elongation assays, we examined ABA response of the slead1 mutants and found that ABA sensitivity in the mutants was increased. By using qRT-PCR, we further show that the expression of some of the ABA biosynthesis and signaling component genes were increased in the slead1 mutants. Taken together, our results suggest that SlEAD1 is an ABA response gene, that SlEAD1 is a novel EAR motif-containing transcription repressor, and that SlEAD1 negatively regulates ABA responses in tomato possibly by repressing the expression of some ABA biosynthesis and signaling genes. [ABSTRACT FROM AUTHOR]

To avoid signal interference in L1 frequency and provide various services, GPS has updated a modern signal, called L1C, which has been tested with three QZSS satellites launched in 2017. In December 2018, the first GPS III satellite was launched, which implies improved joint positioning using GPS and QZSS L1C signal. The L1C signal offers a series of advanced designs in signal modulation, message structure and coding. We present complete methodologies for joint L1C signal receiving and processing. For the transmitted signals, we present a methodology and results from collecting and assessing Binary Offset Carrier (BOC) modulation and time-multiplexed BOC (TMBOC) modulation used in the L1C signal. Using the same omnidirectional antenna and test equipment, we collected the L1C signal in Xi'an and Sanya, China, respectively. The experiments in Xi'an verify the joint positioning method to complement the GPS III and QZSS satellite constellations. Our methodology evaluates the ranging difference and positioning error of BOC and TMBOC modulation under the same environment and satellite constellation configuration in Sanya. It is also verified that the joint positioning error is less than the QZSS-only positioning due to the optimization of the satellite constellation. [ABSTRACT FROM AUTHOR]

A biochar (BC) harbored Ag 3 PO 4 /α-Fe 2 O 3 type-Ⅰ heterojunction (Ag-Fe-BC) was prepared by a hydrothermal-impregnation method to transfer active center of heterojunctions. The electrochemical and spectroscopic tests demonstrated that BC enhanced the catalytic performance of the heterojunction by enhancing photocurrent, reducing fluorescence intensity, and facilitating separation of electron-hole pairs. The photocatalytic activity showed the Ag-Fe-BC (5:1:3) could degrade Rhodamine B (20 mg/L) by up to 92.7%, which was 3.35 times higher than Ag 3 PO 4 /α-Fe 2 O 3 . Tetracycline and ciprofloxacin (20 mg/L) were degraded efficiently by 58.3% and 79.4% within 2 h, respectively. Electron paramagnetic resonance and scavenging experiments confirmed the major reactive oxygen species (ROS) consisted of singlet oxygen ( 1 O 2 ) and superoxide (·O 2 - ). Excellent RhB adsorption and electrons capturing capacity of BC facilitated electron-hole pairs separation and ROS transferring to target organics followed by elevated degradation. Thus, a facile method was proposed to synthesize a highly efficient visible-light responsive photocatalyst for degradation of various organics in water., (Copyright © 2022 Elsevier Ltd. All rights reserved.)