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In order to provide references for the safe use in engineering applications, the corrosion behavior and post-corrosion mechanical properties of HRB400 reinforcement steel, exposed to a 3.5% NaCl solution in two distinct environments-bare and embedded in concrete were investigated through immersion corrosion test. For HRB400 reinforcement steel embedded in concrete, two approaches were employed: the fabrication of reinforced concrete and the simulation of concrete pore fluid. Initially, HRB400 reinforcement steel, both in bare form and embedded in concrete, was immersed in a 3.5% (mass fraction, the same below) NaCl solution. And soaking the HRB400 reinforcement steel in a saturated calcium hydroxide solution (with addition of 3.5% NaCl solution). The weight loss rate and corrosion rate of the HRB400 reinforcement steel under different corrosion times were calculated separately. Subsequently, the mechanical properties of the corroded HRB400 reinforcement steel were assessed using MTS testing machine. Results showed that as the immersion corrosion time prolonged, the average corrosion rate of HRB400 reinforcement steel across the three environments gradually decreased, while the rate of weight loss increased. Additionally, there was a decline in yield strength, tensile strength, and elongation rate. In the 3.5%NaCl solution, the elongation of HBR400 reinforcement steel in bare form and embedded in concrete decreased with the extension of soak time. However, in the saturated calcium hydroxide solutionl (with addition of 3.5%NaCl solution), the elongation showed a trend of mcreasing and decreasing.

Indium phosphide is widely used in electronics and photovoltaic devices due to its high electro-optical conversion efficiency, high electron mobility, and good radiation resistance. Defects are the main limitation for the performance of InP devices. In this work, based on hybrid functional with finite size correction, electronic properties of intrinsic and H-related defects have been investigated in InP. We found that PIn defect is the most stable intrinsic defect with the lowest formation energy. Defect signals detected experimentally are defined by our calculated results. Experimentally observed electron traps with the energy level of EC −0.66 eV and EC −0.68 eV are ascribed to the transition level ɛ(−1/−2) and ɛ(−2/−3) of In vacancies. The hydrogenated vacancies in InP have been systematically reported in the present work. Formation energies of H-related defects indicate that hydrogen atoms prefer to bind to In vacancy than P vacancy. The formation energy of In vacancy decreases with the addition of H, while that of P vacancy increases. For hydrogenated In vacancies, it captures fewer electrons than bare In vacancies when the Fermi level is close to CBM. Especially for the VIn −3H structure, it is 0 charge state in all Fermi levels so that it will not tend to capture electron or hole. Our work is helpful to explain experimental phenomena and radiation-induced damages and improve the performance of InP devices. [ABSTRACT FROM AUTHOR]

Underwater optical communication (UOC) based on the novel photoelectrochemical (PEC) type photodetector has garnered substantial interest in the field of marine resource exploration and ocean investigation due to its strong operability, self‐powered capability, and large sensitive area in harsh underwater environments. To achieve high sensitivity, fast transmission speed, and broadband response characteristics, vertical‐GaS nanosheets‐based PEC photodetectors are prepared by chemical vapor deposition for UOC application. The GaS based PEC photodetector exhibits excellent self‐powered photodetection and a broad UV–vis photoresponse range as well as high stability performance in both Na2SO4 electrolyte and seawater. Notably, it also demonstrates an exceptional photoresponsivity of 11 mA W−1 coupled with a fast response and recovery time of 12.9 and 13 µs which are superior to those of 2D layered materials and conventional wide‐bandgap semiconductors. These improvements are mainly due to the large surface area, short diffusion length, as well as high carrier mobility of vertically‐oriented GaS nanosheets. Strikingly, the constructed GaS photodetector showcases a broad bandwidth exceeding the −3 dB cutoff frequency of 55.3 kHz during UOC testing, successfully enabling transmission and decoding of character information. This work establishes the groundwork for developing high‐performance, self‐powered UV–vis photodetectors adaptable to UOC using PEC technology. [ABSTRACT FROM AUTHOR]

The rational design of a semiconductor heterostructure plays a crucial role in achieving high-performance photoelectrochemical (PEC) applications, such as photodetectors and water splitting due to the diverse functions of the heterointerface in light absorption, corrosion protection, and carrier transportation. Herein, we propose an approach by fully attaching Bi2S3 nanoparticles onto Bi2MoO6 nanorods to fabricate a photoanode for efficient self-powered PEC photodetection and water splitting. This photoanode exhibits remarkable responsivity (11.50 mA/W), rapid response time (200 μs), excellent photon-to-electron conversion efficiency (32.02%), and long-term stability (30,000 s) even without an external bias voltage. These enhancements can be attributed to effective charge separation, unique nanostructural morphology, and an enhanced light capture ability. Leveraging these advantages, the Bi2S3/Bi2MoO6 heterostructure demonstrates an exceptionally high, stable, and bias-free PEC hydrogen evolution rate of 418.95 μmol/cm2/h, surpassing that of both pure Bi2S3 and Bi2MoO6 by factors of 249.38 and 55.38, respectively. Furthermore, compared to previously reported Bi2MoO6-related heterostructures, the Bi2S3/Bi2MoO6 heterostructure exhibits superior PEC catalytic performance. [ABSTRACT FROM AUTHOR]

Restricted by the existing construction technology, there are a lot of disconnections in the angle steel components of transmission towers. At present, there are more studies on single angle steel or cross bracing, but less on the main member containing disconnection joints. According to the disconnection position in the main member, an upper end disconnection, middle end disconnection, and lower end disconnection were designed in this paper. At the same time, a tower section model of a connected main member and a tower section model of a disconnected main member were established and analyzed by finite element analysis. Considering the loadings acting on transmission towers, the two load conditions of axial loading and tension–compression coupling are set. Considering the loadings acting on transmission towers, the influences of the combination form of the inner and outer steel cladding and the steel cladding area ratio on the ultimate bearing capacity of the main member were studied under 72 groups of different tower sections applied with axial loadings. The influence of the disconnection joints on the stability of the tower section was studied under 24 groups of different tower sections applied with tension and compression coupled loading conditions. Referring to the specifications, the slenderness ratio correction factor formula of the disconnect main member can be derived. The results indicate that when designing the disconnection joint in the main member, it is recommended to choose a middle end disconnection with a steel cladding area ratio of 1.0. [ABSTRACT FROM AUTHOR]

SUMMARY: Redox changes of pyridine nucleotides in cellular compartments are highly dynamic and their equilibria are under the influence of various reducing and oxidizing reactions. To obtain spatiotemporal data on pyridine nucleotides in living plant cells, typical biochemical approaches require cell destruction. To date, genetically encoded fluorescent biosensors are considered to be the best option to bridge the existing technology gap, as they provide a fast, accurate, and real‐time readout. However, the existing pyridine nucleotides genetically encoded fluorescent biosensors are either sensitive to pH change or slow in dissociation rate. Herein, we employed the biosensors which generate readouts that are pH stable for in planta measurement of NADH/NAD+ ratio and NADPH level. We generated transgenic Arabidopsis lines that express these biosensors in plastid stroma and cytosol of whole plants and pollen tubes under the control of CaMV 35S and LAT52 promoters, respectively. These transgenic biosensor lines allow us to monitor real‐time dynamic changes in NADH/NAD+ ratio and NADPH level in the plastids and cytosol of various plant tissues, including pollen tubes, root hairs, and mesophyll cells, using a variety of fluorescent instruments. We anticipate that these valuable transgenic lines may allow improvements in plant redox biology studies. Significant Statement: Monitoring dynamic changes in pyridine nucleotides (e.g., NADPH and NADH/NAD+ ratio) in plants at the subcellular level is a major obstacle in plant bioenergetics research. Genetically encoded fluorescent biosensors are considered to be the best option so far because they provide fast, accurate, and real‐time readouts. Here, we present a detailed study on the application of pyridine nucleotide biosensors, and we anticipate that these transgenic lines will be useful in plant redox biology studies. [ABSTRACT FROM AUTHOR]

Legumes perform symbiotic nitrogen fixation through rhizobial bacteroids housed in specialised root nodules. The biochemical process is energy‐intensive and consumes a huge carbon source to generate sufficient reducing power. To maintain the symbiosis, malate is supplied by legume nodules to bacteroids as their major carbon and energy source in return for ammonium ions and nitrogenous compounds. To sustain the carbon supply to bacteroids, nodule cells undergo drastic reorganisation of carbon metabolism. Here, a comprehensive quantitative comparison of the mitochondrial proteomes between root nodules and uninoculated roots was performed using data‐independent acquisition proteomics, revealing the modulations in nodule mitochondrial proteins and pathways in response to carbon reallocation. Corroborated our findings with that from the literature, we believe nodules preferably allocate cytosolic phosphoenolpyruvates towards malate synthesis in lieu of pyruvate synthesis, and nodule mitochondria prefer malate over pyruvate as the primary source of NADH for ATP production. Moreover, the differential regulation of respiratory chain‐associated proteins suggests that nodule mitochondria could enhance the efficiencies of complexes I and IV for ATP synthesis. This study highlighted a quantitative proteomic view of the mitochondrial adaptation in soybean nodules. [ABSTRACT FROM AUTHOR]