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The copper (Cu)-beryllium (Be) alloy is a critical material for high-performance photomultiplier cathodes. The microstructure evolution of the β phase in the Cu-2.8Be alloy subjected to cooling rate ranging from 0.5 to 80 °C/s after heat treatment. The non-isothermal phase transformation kinetics equation of the alloy was derived. At a cooling rate of 0.5 °C/s, the β phase completely transformed into the α phase and γ phase through a eutectoid reaction (β → α + γ). The γ phase preferentially precipitates at locations with higher free energy, such as grain boundaries and defects in the parent phase. The orientation relationship between the α phase and the γ phase follows the Kurdjumov-Sachs (K–S) relationship ([110]α∥[111]γ; (11‾1‾)α∥(01‾1)γ), and the α phase nucleates and grows with a twin relationship to the Cu matrix. As the cooling rate increases, the transformation fraction of the β phase decreases. The critical cooling rate at which the β phase eutectoid reaction is completely suppressed is 80 °C/s. A non-isothermal phase transformation kinetics equation for the β phase eutectoid transformation was established: f(r)=1−exp{−{34.703r−1.062[exp(−0.9107r)−0.3575]}2.2}, elucidating the relationship between the phase transformation fraction and the cooling rate, which provides a theoretical basis for controlling the microstructure of Cu–Be alloy through heat treatment. Validated by the Cu-3.3Be alloy, this equation demonstrates excellent universality.

Copper-based alloys have garnered significant attention for their potential in antimicrobial applications aimed at mitigating medical-related infections. Nonetheless, the alloying elements in conventional copper alloys frequently exhibit biotoxicity. This study explored the corrosion behavior, antimicrobial activity, and ion release of Cu–Fe alloys with varying iron contents and aging treatment. The results indicate that increasing the iron content in Cu–Fe alloys and applying appropriate aging treatment can enhance both the antibacterial efficiency and corrosion rate. Transmission electron microscopy (TEM) observations revealed a corrosion mechanism in which dispersed iron phases act as nucleation sites. These nanoscale precipitates increase the Cu/Fe interfacial area, thereby promoting ion release at the interface. Furthermore, in-situ scanning electron microscopy (SEM) revealed that corrosion products are more likely to detach in iron-rich segregated areas, which effectively promotes the sustained release of copper ions.

Multistage thermomechanical treatment experiments were conducted on Cu–Ni–Co–Si–Mg alloy strip prepared by the Heating Cooling Combined Mold (HCCM) horizontal continuous casting-cold rolling process. Effects of various heat treatments on the microstructure, mechanical properties, and electrical conductivity of the alloy were studied. The strengthening mechanisms and factors influencing the performance of each process has been analyzed. The tensile strength, yield strength, and electrical conductivity of Cu–Ni–Co–Si–Mg alloy can reach 894 MPa, 855 MPa, and 47.1 %IACS after a third-stage of thermomechanical treatment (TTMT). The cold rolling in first-stage of thermomechanical treatment (FTMT) not only caused work hardening of the alloy but also promoted the precipitation of solute atoms and the growth of second phase particles, limiting the increase in strength. Second-stage of thermomechanical treatment (STMT) effectively hindered the excessive growth of second phase particles in FTMT but shortened recrystallization process. The superior performance of Cu–Ni–Co–Si–Mg alloy after TTMT was attributed to dispersive precipitation of Ni, Co, and Si elements as (Ni, Co) 2Si phases in the copper matrix, strengthening the interaction between the precipitates and dislocations. A short process of HCCM horizontal continuous casting-cold rolling-thermomechanical treatment was developed to produce a high strength and highly electrically conductive Cu–Ni–Co–Si alloy strip used in lead frames.

Complex mapping relationships between high-entropy alloy compositions and performances struggle to precisely elucidate by traditional machine learning models, hindering the accurate and efficient design of high-performance alloys. In this work, a novel alloy design strategy combined self-decision deep neural network, data reconstruction with network structure optimization was proposed, which effectively enhanced the model's ability to predict the mapping relationships between high-dimensional composition spaces and mechanical properties of alloy. Compared to other machine learning methods, significantly improves model prediction accuracy (hardness model: 97.98%; strength model: 94.40%). Through above model, the mechanical properties of 308 new (CuNiMn)-X high-entropy copper alloys was studied added other elements such as Al, Ti, Cr, and Fe, which designed and produced a novel (CuNiMn)60Al20Cr20 alloy with high hardness of 474 HV, high compressive strength of 2322 MPa, and high fracture strain of 25.20%. The primary factors influencing alloy performance and their respective thresholds were also quantitatively revealed (hardness: electronegativity deviation (0.02, 0.1) and nuclear charge deviation (0, 0.25); compressive strength: mean nuclear charge (25, 30) and mean atomic radius (134 p.m.)). These findings provide a new perspective and approach for the design and mechanism understanding of high-performance alloys with complex compositions.

Cu–Al2O3–TiB2 is an important high-performance dual-phase dispersion strengthened copper alloy. The problem of serious coarseness and agglomeration of TiB2 and Al2O3 particles is a bottleneck that restricts the preparation of high-performance Cu–Al2O3–TiB2 alloys by traditional liquid-phase in-situ reaction method. In this paper, an idea of combining the split cavity melting of complex reactants and efficient solidification of melt was proposed, and a new liquid phase in-situ reaction technology for dual-phase strengthened metal matrix composites was invented. Compared with the traditional liquid phase in-situ reaction method, the strengthening particles in the Cu-0.75Al2O3-0.75TiB2 (wt.%, nominal composition) prepared by the new liquid phase in-situ reaction technology were more uniform, and the tensile strength and hardness were significantly improved. Large-deformation cold rolling can improve distribution of particles. With the increase of deformation, the main deformation mode of the composite changed from matrix plastic deformation to matrix-particle shear deformation, with the main fracture mechanism changing from particle-matrix interface fracture to particle shear fracture. The new liquid phase in-situ reaction technology effectively solved the problem of particle coarsening and agglomeration in Cu–Al2O3–TiB2 composites. The new liquid phase in-situ reaction technology combined with large deformation is a new process with high efficiency and short flow for preparing dual-phase dispersion strengthened copper alloys.

In this study, the effects of differences in grain size, grain boundary type and misorientation on the initiation of discontinuous precipitates are investigated for the Cu–5Ni–1.25Si alloy. Samples with different grain sizes are obtained by thermomechanical treatment, and the smaller the grain size, the higher the percentage of discontinuous precipitate at the same aging time, while there is no significant difference in the growth rate of the reaction front of discontinuous precipitates. EBSD is used to study the effect of grain boundary misorientation on discontinuous precipitates, the characteristics of discontinuous precipitates initiation on different grain boundaries are investigated by multivariate statistical analysis. It is found that discontinuous precipitates only initiate from random grain boundaries instead of coincident site lattice boundaries, where random grain boundaries with misorientation angles of 30–50° are more prone to discontinuous precipitates. And the initiation of DPs at different misorientation axes is different. There is a clear borderline for the axes such as , , and . The grain boundaries below this borderline do not initiate DP, while all grain boundaries below this angle initiate DPs. The cases for axes such as , , and are more complicated. On these misorientation axes, grain boundaries with lower or higher misorientation angles do not initiate DPs, while grain boundaries at intermediate range misorientation angles do initiate DPs.

Recrystallization behaviour and texture evolution of Fe–3Si alloy strip by electropulsing treatment (EPT) were investigated through EBSD and X-ray diffraction techniques. It was found that EPT remarkably reduced recrystallization temperature of Fe–3Si alloy, induced full recrystallization at 550 °C in a short time (10 s), fine and uniform recrystallization grains accompanied with a small amount of Goss orientated grains were obtained. Compared with the conventional isothermal annealing, EPT effectively promoted the nucleation of Goss orientated recrystallization grains and suppressed swallowing of Goss orientated grains by other oriented grains due to both short treatment time and fast cooling rate of EPT, which was the main reason for EPT induced Goss orientated grains. EPT can work as a new heat treatment process for silicon steel to simultaneously obtain Goss orientated as well as fine and uniform grains, indicating the advantages of high efficiency, low energy consumption and low cost.

Cu-1.3 wt%Ni-1.0 wt%Co-0.9 wt%Si-0.1 wt%Mg alloy strip with 10 mm in thickness produced by heating-cooling combined mold (HCCM) horizontal continuous casting was cold rolled. Microstructure evolution and mechanical properties of the cold-rolled alloy strips with different reduction were studied, and the deformation mechanism was clarified. The results showed that the continuous casting strips had axial columnar grain with main orientations and straight small angle grain boundaries, the elongation after fracture was up to 25.0%, which can be directly processed by large deformation cold rolling, and the maximum cumulative cold deformation was up to 99%.When the reduction was 40% and 60%, the dislocation bands crossed each other and shear bands formed, and the alternating distribution of soft/hard oriented grains were conducive to improve the deformation coordination ability of micro-region under high strain. When the deformation exceeded 80%, deformation twins formed and the twins had strong interaction with the shear band and grain boundaries, resulting in strong shear and rotation of the local grains. The tensile strength and hardness increased from 464 MPa to 137HV of the as-cast strip to 629 MPa and 208HV with reduction 90%, respectively, while the elongation decreased from 25.0% to 4.1%. These results can lay a foundation for the development of compact method for producing high performance Cu–Ni–Co–Si alloy strips.

Improving high-temperature strength and resistance to high-temperature softening is an important method to promote the application of high-performance Cu-Cr-Zr alloy in fields such as resistance welding electrodes and high-speed railway contact wires. A Cu-1.0Cr-0.4Zn-0.1Zr-0.05Si alloy was designed and the combining effects of Zn and Si elements on the microstructure and high-temperature mechanical properties of the alloy were studied. The tensile strength of the alloy at room temperature was 556 MPa, and it was 349 MPa at 500℃ with a softening temperature of 620℃. The main strengthening phases of the alloy were submicron Cr3Si and nano-scaled Cr-rich precipitates. The Zn elements were uniformly solid-solved in the Cu matrix, and the addition of Zn and Si elements significantly retarded the phase transformation of the Cr-rich precipitates. Thermodynamics and kinetics analysis showed that Zn and Si elements promoted the dispersive precipitation of the nano-scaled FCC coherent Cr-rich precipitates by reducing the nucleation energy barrier, while the Si and Zr elements inhibited the coarsening of the Cr-rich precipitates by enriching at the phase boundaries, effectively impeding dislocation motion and grain boundary migration, which mainly contributed to good high-temperature strength and resistance to softening of the Cu-Cr-Zn-Zr-Si alloy.

60NiTi alloy is an important biomedical, structural and functional material. In this paper, the effects of heat treatment (temperature, time and cooling rate) on the microstructure and properties of 60NiTi alloy were studied, and the softening and hardening mechanisms were revealed. The results showed that the number of Ni4Ti3 phase enhanced with an increase of the cooling rate and the precipitation of Ni3Ti phase was inhibited after annealing at 950∼1075 °C followed by water-cooling. The orientation relationship between NiTi matrix and Ni4Ti3 phase obey the rule: [111]NiTi//[0001]Ni4Ti3 and (123¯)NiTi//(112¯0)Ni4Ti3. The faster the cooling rate was, the higher the hardness of the alloy was. The hardness of alloy under different cooling rate ranked from high to low was water-cooling, oil-cooling, liquid nitrogen-cooling, air-cooling and furnace-cooling. The hardness of the 60NiTi alloy was 316 HV after annealing at 1075 °C for 4 h followed by furnace-cooling, and the hardness sharply increased to 669 HV after annealing at 1075 °C for 4 h followed by water-cooling. The phase transformation of Ni4Ti3→Ni3Ti during cooling mainly contributed to the hardness decrease of the 60NiTi alloy.

A Cu-9Ni-6Sn alloy bar with axial columnar grains was prepared by directional solidification. The effects of aging on the microstructure and mechanical properties of the alloy were studied. The results showed that the alloy had columnar grains oriented along the axis and underwent continuous cold-drawing with a total deformation amount of 85%, a fibrous structure along the axis was formed. For the homogenized alloy, the tensile strength is 385 MPa, the hardness is 80 HV, and the elongation after fracture can reach 38.5%. After aging at 360 °C for 120 min, (Cu, Ni)3Sn phase precipitated intermittently along the grain boundary, and the tensile strength and elongation of the alloy were 1057 MPa and 7.1%, respectively. With increasing aging time to 240 min, the number of (Cu, Ni)3Sn phase increased and coarsened obviously, forming a precipitation-free zones, with occurrence of recrystallization of the Cu matrix. The preparation of Cu-9Ni-6Sn alloy billet by directional solidification, combined with large-deformation drawing and aging, is a new method to prepare high performance Cu-9Ni-6Sn alloy wire.

Criminals targeting and exploiting older adults in online environments are of great concern. This study systematically retrieved and analyzed articles on the psychological characteristics of older adult victims of online fraud. First, we found that there was no evidence that older adults were more prevalent than other individuals of other ages among online fraud victims, and current researchers have focused more on why older adults are easy targets for fraud (susceptibility to being cheated). Second, research on psychological factors of older adults' susceptibility to online fraud has mainly focused on cognitive function, trust traits, and other personality traits, such as social loneliness, the Big Five personality traits, and self-control. Among them, most researchers claim that the cyber-cheating of older adults may be due to a decline in their cognitive function. However, there has not been a consensus on how cognitive function and physical and mental conditions affect older people who are cheated. Third, techniques (i.e., methods and techniques used by fraudsters) and experience (i.e., familiarity with internet technology or fraud) may be related to the susceptibility of older adults to fraud, and these studies have also not yet generated a consensus supported by reliable data. Based on the above research uncertainties, we propose that fraud prevention and control strategies for older adults should be applied with caution.

Multicomponent solid forms of low molecular weight drugs, such as co-crystals, salts, and co-amorphous systems, are a result of the combination of an active pharmaceutical ingredient (API) with a pharmaceutically acceptable co-former. These solid forms can enhance the physicochemical and pharmacokinetic properties of APIs, making them increasingly interesting and important in recent decades. Nevertheless, predicting the formation of API multicomponent solid forms in the early stages of formulation development can be challenging, as it often requires significant time and resources. To address this, empirical and computational methods have been developed to help screen for potential co-formers more efficiently and accurately, thus reducing the number of laboratory experiments needed. This review provides a comprehensive overview of current screening and prediction methods for the formation of API multicomponent solid forms, covering both crystalline states (co-crystals and salts) and amorphous forms (co-amorphous). Furthermore, it discusses recent advances and emerging trends in prediction methods, with a particular focus on artificial intelligence.

Cancer has emerged as a leading cause of death worldwide. However, the pursuit of precise cancer therapy and high-efficiency delivery of antitumor drugs remains an enormous obstacle. The major challenge is the lack of a smart drug delivery system with the advantages of biodegradability, biocompatibility, stability, targeting and response release. Zein, a plant-based protein, possesses a unique self-assembly ability to encapsulate anticancer drugs directly or indirectly. Using zein as a nanotherapeutic pharmaceutic preparation can protect anticancer drugs from harsh environments, such as sunlight, stomach acid and pepsin. Moreover, the surface functionalization of zein is easily realized, which can endow it with targeting and stimulus-responsive release capacity. Hence, zein is an ideal nanocarrier for the precise delivery of anticancer drugs. Combined with our previous research experiences, we attempt to review the current state of the preparation of zein-based nanocarriers for anticancer drug delivery. The challenges, solutions and development trends of zein-based nanocarriers for precise cancer therapy are discussed. This review will provide a guideline for precise cancer therapy in the future.

Electropulsing process of magnesium alloy has attracted a substantial attention, owing to the advantage of the low consumption, high efficiency and short processing period. High-density multiple pulse treatment (HMPT) in the paper can be applied into the industry, due to the continuous process. Therefore, the evolution information of AZ 31 strips treated by HMPT, such as the surface temperature, the microhardness and the microstructure was observed. It was indicated that HMPT belonged to the process of the rapid temperature change. The thermal effect produced by high-density multiple pulse was investigated. On the basis, the linear model of maximum stable surface temperature of AZ 31 was deduced in theory and consistent with the experimental data; and its influence on the recrystallization nucleation in HMPT were investigated. Compared with the conventional heat treatment, the recrystallization temperature decreased from 483 K to 465 K (maximum surface temperature) during HMTP, as well as the recrystallization time was shortened by 102, resulting from the significant increase of dislocation climbing speed. The complex coupling between thermal effect and athermal effect made dislocation climbing motion remarkable increase through quantitative calculation and qualitative analysis, and the remarkable growth of dislocation climbing speed was calculated about 104 during HMPT.

Plant traits reflect the response and adaptation of plants to environmental changes and play important roles in the prediction of the effects of different environmental conditions on plants and plant-mediated processes. However, few studies have focused on the traits of nonvascular plants, such as bryophytes, although such plants are important participants in the primary productivity and biogeochemistry in harsh environments. In this study, the adaptive morphological traits and their interactions in the moss species that adapt to harsh and acute changeable environment were determined. Environmental factors that drive the changes in these traits were also evaluated. A total of 43 specimens of Didymodon rigidulus were collected from 38 sampling sites in arid and semi-arid regions in Tibet. Twelve morphological traits were investigated by microscope measurement, and then their interrelations and relations to environmental variables were quantified by employing Spearman’s correlation analysis, hierarchical partitioning analysis, and partial least squares path modeling. Results showed that along with the environmental gradient, the plant height, leaves, and cells of D. rigidulus had changed significantly, and these parameters were largely interpretable in functional and adaptive terms. The lower the mean annual temperature (MAT) was, the thicker was the surface cell wall and the wider was the cell cavity of D. rigidulus. The higher potential evapotranspiration (PET) was, the thicker was the surface cell wall but the smaller were the leaves. MAT and PET were the main driving forces for the development of such traits of D. rigidulus. These results provide important insight into the adaptive syndrome of nonvascular plants associated with stress tolerance in the varied and harsh environment in Tibet. This study indicated the importance of considering the effects of climate change, especially the warming temperature on species adaption and community assemblage.

Enzymes, as natural catalysts with remarkable catalytic activity and high region-selectivities, hold great promise in industrial catalysis. However, applications of enzymatic transformation are hampered by the fragility of enzymes in harsh conditions. Recently, metal–organic frameworks (MOFs), due to their high stability and available structural properties, have emerged as a promising platform for enzyme immobilization. Synthetic strategies of enzyme-MOF composites mainly including surface immobilization, covalent linkage, pore entrapment and in situ synthesis. Compared with free enzymes, most immobilized enzymes exhibit enhanced resistance against solvents and high temperatures. Besides, MOFs serving as matrixes for enzyme immobilization show extraordinary superiority in many aspects compared with other supporting materials. The advantages of using MOFs to support enzymes are discussed. To obtain a high enzyme loading capacity and to reduce the diffusion resistance of reactants and products during the reaction, the mesoporous MOFs have been designed and constructed. This review also covers the applications of enzyme-MOF composites in bio-sensing and detection, bio-catalysis, and cancer therapy, which is concerned with interdisciplinary nano-chemistry, material science and medical chemistry. Finally, some perspectives on reservation or enhancement of bio-catalytic activity of enzyme-MOF composites and the future of enzyme immobilization strategies are discussed.

A clear understanding of which factors play an important role in the development of the soil microbial community in orchards will benefit our understanding of ground cover impacts on soil nutrient cycling. Thus, in the present study, grass properties, soil properties, and soil microbial community structure were determined in a citrus orchard after 5 years of management with different types of ground cover (NG: natural grass, LP: monoculture of legumes, and NL: mixed culture of natural grasses and legumes) to evaluate how ground cover biomass and nitrogen-fixing ability drive soil physicochemical and microbial traits. Plant biomass carbon (BC) and nitrogen (BN) were significantly higher in LP and NL than NG and showed a significant (p < 0.01) positive relationship with soil total carbon (TC), NO3−-N (NN), and dissolved organic carbon (DOC) content. In addition, the amount of biologically fixed nitrogen (FixN) showed a significant positive relationship with soil total nitrogen (TN) (p < 0.05) and NH4+-N (AN) content (p < 0.01). We also observed a difference in the soil microbial community structure between plots with and without legumes. The TC and BN were the most influential factors driving bacterial and fungal communities, respectively. Nevertheless, FixN explained less than 9% of the differences in soil bacterial and fungal communities. Our results suggest that grass biomass and FixN are the strong drivers of soil chemical properties, whereas ground cover and soil properties both contribute significantly to the soil microbial community structure.

Tibet makes up the majority of the Qinghai-Tibet Plateau, often referred to as the roof of the world. Its complex landforms, physiognomy, and climate create a special heterogeneous environment for mosses. Each moss species inhabits its own habitat and ecological niche. This, in combination with its sensitivity to environmental change, makes moss species distribution a useful indicator of vegetation alteration and climate change. This study aimed to characterize the diversity and distribution of Didymodon (Pottiaceae) in Tibet, and model the potential distribution of its species. A total of 221 sample plots, each with a size of 10 × 10 m and located at different altitudes, were investigated across all vegetation types. Of these, the 181 plots in which Didymodon species were found were used to conduct analyses and modeling. Three noteworthy results were obtained. First, a total of 22 species of Didymodon were identified. Among these, Didymodon rigidulus var. subulatus had not previously been recorded in China, and Didymodon constrictus var. constrictus was the dominant species. Second, analysis of the relationships between species distributions and environmental factors using canonical correspondence analysis revealed that vegetation cover and altitude were the main factors affecting the distribution of Didymodon in Tibet. Third, based on the environmental factors of bioclimate, topography and vegetation, the distribution of Didymodon was predicted throughout Tibet at a spatial resolution of 1 km, using the presence-only MaxEnt model. Climatic variables were the key factors in the model. We conclude that the environment plays a significant role in moss diversity and distribution. Based on our research findings, we recommend that future studies should focus on the impacts of climate change on the distribution and conservation of Didymodon.