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Conventional welding poses significant challenges when directly joining titanium alloys and stainless steels due to their inherent physical and metallurgical properties variances. The primary challenge in achieving durable joints is to avoid the formation of brittle Ti–Fe intermetallic compounds (IMCs). In this study, Hf-doped amorphous filler material was employed to join TC4/SS316L dissimilar metals by vacuum brazing, achieving a maximum shear strength of 380 MPa under 910 °C/10 min at 1.25 at.% Hf. The interfacial microstructures consisted of the sequence: β-Ti/α-Ti/β-Ti + Ti2(Cu, Ni)/Ti2(Cu, Ni)/Ti2(Zr, Ni)+TiCu/Ti2(Ni, Cu, Fe)/γ-(Fe, Ni) + σ. This study presents a successful approach for the brazing of titanium alloy with stainless-steel alloy for high-precision components in the field of aerospace and nuclear sectors. [ABSTRACT FROM AUTHOR]

(1) Background-Realizing coordinated development of ecology and economy has become a new driving force for improving the quality of green economy development and promoting modernization. The existing researches are more inclined to make a single evaluation of the synergistic relationship between high-level protection of forestry ecology and high-quality development of forestry economy in a specific period, lack the judgment of the long-term change trend of this relationship and the discussion on the specific issues such as the change of forestry policies and the optimization of forestry systems according to the trend. (2) Methods-The paper first analyzed the rationality and necessity of the coordinated development of high-level protection of forestry ecology and high-quality development of forestry economy. Then, from the perspective of synergy between high-level protection and high-quality development, this paper evaluated the effect of high-level protection of forestry ecology and the level of high-quality development of forestry economy from 2007 to 2021 by using ecological footprint model and entropy method, and identified the types of synergistic relationship between the two through coupling coordination degree model. Finally, the gray prediction model was used to predict and analyze the coupling coordination degree between them. (3) Results-First, from 2007 to 2021, Chinas forestry ecosystem has always been in a state of ecological surplus and strong sustainability, and has achieved positive results in the construction of forestry ecology. Second, the development level of China s forestry economy shows a fluctuating growth trend on the whole from 2007 to 2021. Factor driving force has a significant long-board effect on the high-quality development of forestry economy, while environmental carrying capacity has a significant short-board effect on the high-quality development of forestry economy. The policy of reducing logging and limiting logging, especially the policy of "prohibiting logging", has had a certain impact on the high-quality development of forestry economy in a certain period of time. Third, from 2007 to 2021, the synergistic relationship between high-level protection of forestry ecology and high-quality development of forestry economy in China continues to improve, and the coupling development effect between the two is better than the coordinated development effect. Fourth, it is predicted that by 2030, the syner-gistic relationship between high-level protection of forestry ecology and high-quality development of forestry economy in China will maintain an excellent level of coordinated development for a long time. (4) Conclusions and Discussions-The level of high-quality development of China s forestry economy shows a trend of fluctuating growth on the whole. Factor driving force and environmental carrying capacity have significant long-board and short-board effects on the level of high-quality development of forestry economy, respectively. In addition, forest logging reduction and limiting, especially the policy of "forbidden logging", have caused a certain impact on the development of forestry economy in a certain period of time. With the improvement of the level of forestry ecological industrialization, the impact of this kind of impact is gradually alleviated. The synergistic relationship between high-level protection of forestry ecology and high-quality development of forestry economy continues to improve. It is predicted that by 2030, the synergistic relationship between high-level protection of forestry ecology and high-quality development of forestry economy in China will maintain an excellent level of coordinated development for a long time. In order to achieve overall and balanced development, it is necessary to pay attention to and support the transformation and upgrading of forestry economy and promote the cultivation and development of forestry ecological economy. Under the premise of consolidating the effect of forestry ecological protection, we must adhere to the development concept of green economy, explore the new impetus for the transformation and upgrading of forestry economy, and deepen the practice paths of forestry ecological industrialization innovation, so as to continuously improve the synergistic relationship between forestry ecological protection and forestry economic development. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) hampers plant growth and harms photosynthesis. Glutamate (Glu) responds to Cd stress and activates the Ca2+ signaling pathway in duckweed, emphasizing Glu's significant role in Cd stress. In this study, we overexpressed phosphoserine aminotransferase (PSAT), a crucial enzyme in Glu metabolism, in duckweed. We investigated the response of PSAT-transgenic duckweed to Cd stress, including growth, Glu metabolism, photosynthesis, antioxidant enzyme activity, Cd2+ flux, and gene expression. Remarkably, under Cd stress, PSAT-transgenic duckweed prevented root abscission, upregulated the expression of photosynthesis ability, and increased Chl a, Chl b, and Chl a + b levels by 13.9%, 7%, and 12.6%, respectively. Antioxidant enzyme activity (CAT and SOD) also improved under Cd stress, reducing cell membrane damage in PSAT-transgenic duckweeds. Transcriptomic analysis revealed an upregulation of Glu metabolism-related enzymes in PSAT-transgenic duckweed under Cd stress. Moreover, metabolomic analysis showed a 68.4% increase in Glu content in PSAT duckweed exposed to Cd. This study sheds novel insights into the role of PSAT in enhancing plant resistance to Cd stress, establishing a theoretical basis for the impact of Glu metabolism on heavy metal tolerance in plants. [ABSTRACT FROM AUTHOR]

Members of transition metal dichalcogenides, particularly molybdenum disulfide, have been recognized as promising efficient and durable earth‐abundant catalysts for the hydrogen evolution reaction (HER). Despite the recent significant progress, the HER performance of MoS2 is still far from satisfactory, especially at high current densities. Here, a simultaneous multilevel structural control strategy is reported to cooperatively boost hydrogen evolution on 2H‐MoS2, unlocking its potential for practical hydrogen evolution at ampere‐level current densities. By confining the epitaxial growth of few‐layered, curved MoS2 nanosheets within a tubular mesoporous graphitic framework, one can achieve deliberate structural control of MoS2 across seven orders of magnitude on the length scale. The resulting MoS2@C supertubes, benefiting from their unique structural features across atomic‐to‐microscopic scales, are characterized by abundant edge sites and sulfur vacancies, facilitated charge and mass transport, and rapid gas bubble removal. As a consequence, such MoS2@C supertubes exhibit exceptional high‐current‐density HER activity surpassing previously reported 2H‐MoS2 catalysts and even commercial Pt/C catalysts. This work demonstrates the validity of multilevel structural engineering of 2H‐MoS2 by confinement growth, opening a viable route of developing low‐cost catalysts toward practical hydrogen evolution. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) are promising anode materials for sodium-ion batteries (SIBs), but suffer from low rate capability and poor cycling stability. Here, we describe our efforts in designing a unique MoS2-based van der Waals (vdW) superstructure, namely mesoporous MoS2@graphene supraparticles, for realizing unprecedented high-rate, long-life sodium storage. The key to obtaining mesoporous MoS2@graphene vdW supraparticles is the high mass loading of the initially hydrophilic (NH4)2MoS4 precursor into the hydrophobic mesoporous graphene, which is realized through a novel phase-transfer assisted method. Subsequent precursor decomposition confined in ∼11 nm mesopores triggers the epitaxial growth of MoS2 nanosheets featuring a spherically curved geometry and an expanded interlayer spacing. Thanks to the greatly improved electron and ion transport properties enabled by the unique mesoporous vdW superstructure, the resulting MoS2@graphene vdW supraparticles exhibit arguably the best rate performance ever reported. [ABSTRACT FROM AUTHOR]

A facile and scalable exfoliation approach is developed to prepare large-flake, few-layer MoS2 nanosheets with the assistance of carbon nanotubes (CNTs). CNTs not only facilaite the efficient exfoliation of MoS2 nanosheets, but also benefit their subsequent electrochemical applications for both hydrogen evolution and sodium-ion storage. This CNT-mediated exfoliation approach can be extended to other kinds of 2D materials. [ABSTRACT FROM AUTHOR]

Velocity distribution of vertical pipes with large particle slurry plays an important role in pipeline transportation of minerals in hydraulic coal mining and ocean mining industry. The experiments of particle fluidization and particle vertical lift are conducted and the fluidization data of three kinds of large particles are analyzed. The results show that the vortex resistance prevents particles from moving as the coarse particles move in vertical pipes. An additional coefficient method is proposed to study the vortex resistance by increasing the coefficient of vortex resistance before interference. Mathematical model is established to describe the drag coefficient of the vortex by analyzing the influence factors of the experimental data and the drag coefficient of the vortex. In addition, calculation model of the velocity distribution of large particles in vertical pipe is proposed by analyzing the force, the fluid, and the solid momentum. Moreover, the experimental data of particle transport in vertical pipes are utilized to verify and analyze the proposed model.