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The Dragon-I injector based on the induction voltage adder technique is introduced. Twelve ferrite loaded induction cells are connected in a series through central conducting stalks to achieve a pulsed voltage higher than 3.5 MV across the diode. Electrons are extracted from the velvet emitter and guided through the anode pipe by the magnets placed inside the cathode and anode shrouds. Measurements at the exit of injector show that, with an electric field of 200 kV/cm near the velvet surface and suitable magnetic field distribution, an electron beam up to 2.8 kA can be obtained with a normalized emittance of 1040π mm mrad, and energy spread of 2.1% (3σ) around the central energy of 3.5 MeV.

A new in situ thermal piezocone penetration test (T-CPTU) system is developed to determine the thermal properties of soil. It is expected to overcome most of the shortcomings observed in existing in situ test techniques. Based on Fourier's heat conduction equation and pore pressure dissipation theoretical equation, a method for calculating the thermal conductivity, namely the predicted temperature method, was proposed. The accuracy of the T-CPTU probe testing process and thermal conductivity calculation results were verified by numerical simulation, laboratory large-scale model tank tests, and thermal needle tests. Finally, the field data of T-CPTUs at three sites in Nanjing, China, were collected and compared with the laboratory thermal needle tests. The results indicated that the thermal conductivities obtained using T-CPTU were accurate and closer to those of laboratory thermal needle tests for most soils. The thermal conductivities of the undisturbed soil samples measured in the laboratory were lower than those obtained by T-CPTU. Key words: thermal piezocone penetration test (T-CPTU), in situ tests, temperature distribution, thermal conductivity. Un nouveau systeme d'essai de penetration thermique in situ par piezocone (T-CPTU) est developpe pour determiner les proprietes thermiques du sol. Elle devrait permettre de surmonter la plupart des lacunes observees dans les techniques d'essai in situ existantes. Sur la base de l'equation de conduction thermique de Fourier et de l'equation theorique de dissipation de la pression des pores, une methode de calcul de la conductivite thermique, a savoir la methode de la temperature predite, a ete proposee. La precision du processus d'essai de la sonde T-CPTU et les resultats du calcul de la conductivite thermique ont ete verifies par simulation numerique, par des essais en laboratoire sur des reservoirs modeles a grande echelle et par des essais par aiguille thermique. Enfin, les donnees de terrain du T-CPTU sur trois sites a Nanjing, en Chine, ont ete collectees et comparees aux essais par aiguille thermique realises en laboratoire. Les resultats ont indique que les conductivites thermiques obtenues a l'aide du T-CPTU etaient precises et plus proches de celles des tests d'aiguille thermique en laboratoire pour la plupart des sols. Les conductivites thermiques des echantillons de sol non perturbes mesurees en laboratoire etaient inferieures a celles obtenues par T-CPTU. [Traduit par la Redaction] Mots-cles : essai de penetration thermique par piezocone (T-CPTU), essais in situ, distribution de la temperature, conductivite thermique., 1. Introduction With the rapid increase in demand for the utilization of geothermal energy resources, and the importance of soil thermal properties to the design of energy piles, ground source [...]

Aqueous zinc metal battery (AZMB) has received widespread attention due to the advantages of low cost and high safety. However, challenges of dendritic growth, hydrogen evolution reaction, and other side‐reaction impede the performance of the Zn anode. Herein, 4‐amino‐benzene‐sulfonic acid (ABSA) is proposed as an additive to the ZnSO4 electrolyte for improving the performance of AZMB. Combined analyses of theoretical calculations and experiment results, ABSA assumes a pivotal function in constructing an adsorptive layer, facilitating the subsequent formation of a stable sulfur‐rich solid‐electrolyte interphase (SEI). Consequently, the SEI layer modulates the pathway of Zn2+ electrodeposition/dissolution and effectively hinders the deleterious growth of dendrites and unwanted side reactions. As a result, the Zn||Zn cells stably cycles for 2500 h at 1 mAh cm−2/1 mA cm−2 and over 1000 h at 10 mAh cm−2/10 mA cm−2. Significantly, the pouch cell of Zn||VO2 can obtain the specific capacity of 151 mAh g−1 after 100 cycles. This work may provide a new perspective for designing advanced electrolytes from the prospect of interface protection for the AZMB and other metal ion batteries. [ABSTRACT FROM AUTHOR]

In this study, a multilevel drought-induced resistance and resilience analysis (MDRRA) approach was developed to investigate the stability of vegetation in the Yellow River Basin (YRB). MDRRA was quantified by utilizing the Normalized Difference Vegetation Index (NDVI). It was applied to YRB to assess vegetation resistance and resilience to various levels of drought by utilizing precipitation and NDVI data from 2000 to 2019. The results reveal that vegetation resistance and resilience in YRB are affected by drought severity. Monthly and annual changes in SPI over the warm–temperate humid zone of the YRB show a decreasing trend, with rates of 0.001 per decade and 0.034 per decade, respectively; however, the other climatic subregions exhibit an increasing trend, with rates ranging from 0.002 per decade to 0.82 per decade. Over 77.56% of the downstream areas show increases in the annual SPI averages. Drought severity differs across subregions in the YRB. More severe drought events occur in its upper and middle reaches, while less severe ones happen in its lower reaches. As the drought severity increases, the arid and semiarid regions of the mesothermal zone exhibit a decrease in the resistance and resilience indices. MDRRA can help improve the stability and resilience of the ecosystem in the YRB. [ABSTRACT FROM AUTHOR]

Solanum torvum, a wild relative of eggplant in the Solanaceae family, is widely used as a rootstock to prevent various soil-borne diseases. Despite this valued trait, S. torvum seeds exhibit strong seed dormancy, resulting in low-frequency germination and uneven emergence rates during agricultural production. In this study, exogenous gibberellin (GA) was applied to induce the germination of seeds, thereby enabling the application of transcriptome analysis to explore the effects of exogenous GA on germination. A total of 9723 genes were identified to be involved in GA-induced germination of S. torvum seeds. These GA-associated genes were enriched in amino sugar and nucleotide sugar metabolism, glycolysis, the citrate cycle, pyruvate metabolism, hormone biosynthesis, and signaling transduction. Further analysis of these genes reveals that exogenous GA impaired the endogenous biosynthesis of GA. Analysis of the 285 key genes influenced by GA, auxin, abscisic acid (ABA), and other hormones suggests mutual crosstalk in the signaling of various hormones, enabling the joint regulation of the germination of S. torvum seeds. Additionally, a total of 440 genes encoding transcription factors were identified to be responsible for transcriptional reprogramming during GA-induced seed germination, and putative candidate genes responsible for S. torvum seed dormancy and germination, including ABI5, DOG1, DRM1, LEC1, and PIF, were significantly down-regulated in germinated S. torvum seeds. These findings provide the first insights into transcriptome regulation during GA-induced germination of S. torvum seeds. [ABSTRACT FROM AUTHOR]

Addressing the challenges for detecting underwater damage to the structures with pile foundation, this study presents the design of an adsorption-operated robotic system. Initially, a prototype is proposed for an adsorption-operated robot that is equipped with an automatic movement mechanism. To account for the disturbance of the drag force in the control system, a hydrodynamic numerical model for the detection robot is established. The numerical results of the drag force are then integrated into the control system, leading to the design of a force-redeemed active disturbance rejection controller. Furthermore, a novel detection algorithm based on the image segmentation network UNet is developed for the automatic identification of damages. The performance of the controller and detection algorithm is evaluated against traditional methods. The results indicate that the proposed force-redeemed active disturbance rejection controller outperforms traditional PID and ADR controllers in terms of overshoot and adjustment time. Moreover, the developed detection algorithm exhibits superior performance in precision, F1 score, and mean intersection over union compared to the traditional algorithms of FCN, PSPnet, Deeplabv3, and UNet. Overall, this paper advances the technology of autonomous robots for underwater detection in the structures with pile foundation. [ABSTRACT FROM AUTHOR]

Calciumion batteries (CIBs) are an appealing energy storage technology owing to the low redox potential of Ca2+/Ca and the abundant Ca reserves in the earth's crust. However, suitable cathode materials with high capacity and long lifespan are scarce. Herein, VO2(B)/reduced graphene oxide (rGO) heterojunction formed by interfacial V─O─C bonds is constructed and first reported as a cathode material for CIBs, which exhibits an ultrahigh discharge capacity of 319.2 mAh g−1 and exceptional long lifespan (3000 cycles at 500 mA g−1 with capacity retention of 85%). In addition, VO2(B)/rGO heterojunction also shows an outstanding rate capability at 50 °C (127.1 mAh g−1 at 1000 mA g−1). The remarkable electrochemical performance is attributed to the big tunnel structures of VO2(B) and the role of rGO in enhancing electronic conductivity. Density functional theory calculations reveal a feasible Ca2+ diffusion path at the interface. Furthermore, a reversible single‐phase insertion/extraction reaction is revealed by in situ X‐ray diffraction, ex situ Raman, and ex situ X‐ray photoelectron spectroscopy. This work demonstrates that VO2(B)/rGO holds great potential for building high‐capacity and long‐lifespan CIBs. [ABSTRACT FROM AUTHOR]