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The development of a highly efficient, visible-light responsive catalyst for environment purification has been a long-standing exploit, with obstacles to overcome, including inefficient capture of near-infrared photons, undesirable recombination of photo-generated carriers, and insufficient accessible reaction sites. Hence, novel carbon quantum dots (CQDs) modified PbBiO2I photocatalyst were synthesized for the first time through an in-situ ionic liquid-induced method. The bridging function of 1-butyl-3-methylimidazolium iodide ([Bmim]I) guarantees the even dispersion of CQDs around PbBiO2I surface, for synchronically overcoming the above drawbacks and markedly promoting the degradation efficiency of organic contaminants: (i) CQDs decoration harness solar photons in the near-infrared region; (ii) particular delocalized conjugated construction of CQDs strength via the utilization of photo-induced carriers; (iii) π–π interactions increase the contact between catalyst and organic molecules. Benefiting from these distinguished features, the optimized CQDs/PbBiO2I nanocomposite displays significantly enhanced photocatalytic performance towards the elimination of rhodamine B and ciprofloxacin under visible/near-infrared light irradiation. The spin-trapping ESR analysis demonstrates that CQDs modification can boost the concentration of reactive oxygen species (O2•−). Combined with radicals trapping tests, valence-band spectra, and Mott–Schottky results, a possible photocatalytic mechanism is proposed. This work establishes a significant milestone in constructing CQDs-modified, bismuth-based catalysts for solar energy conversion applications. [ABSTRACT FROM AUTHOR]

• Simultaneously He+ and H 2 + irradiations were carried out in pure tungsten. • Three dose percentages of He and H were adopted at 1073 K. • Increasing dose percentages of He promoted loop nucleation. • Geometries of 1/2<111>loops were affected by dose percentages of He and H. • Habit planes of 1/2<111> loops were unaffected by dose percentages of He and H. The interaction among He, H, and irradiation-induced dislocation loops in pure tungsten was examined through 30 keV simultaneous He+ and H 2 + irradiation at 1073 K. Three different He/H concentration ratios (0.1, 1, and 5) were utilized. This study involved the characterization of the number density, average size, and size distribution of loops by varying the dose percentage of He and H. Increasing the dose percentage of He facilitated the loop nucleation. Increasing the total irradiation dose not only increased loop nucleation sites but also changed the loop size distribution from unimodal to bimodal. The specific Burgers vectors and habit planes of loops were carefully determined using the inside-outside method in combination with the g · b invisibility criterion and crystallographic map. The proportion of interstitial 1/2<111> loops exceeded 95 %, in which four Burgers vector variants of 1/2[111], 1/2 [ 1 ¯ 11 ] , 1/2 [ 1 ¯ 1 ¯ 1 ] , and 1/2 [ 1 1 ¯ 1 ] were identified. Increasing the dose percentage of He led to an even distribution of Burgers vector variants. The {110} habit planes were found to deviate at an angle of 35° from the {111} ones. A majority of {111} habit planes were found compared to {110} for 1/2<111> loops. Altering the dose percentage of He or H showed no apparent effect on the habit planes of {111} or {110} for 1/2<111>loops, nor did it affect their average size when situated on {111} or {110}. [ABSTRACT FROM AUTHOR]

Potassium-doped tungsten (KW), as an advanced candidate for first wall material, was developed to mitigate intrinsic embrittlement of bulk W. The addition of gaseous potassium bubbles (KBs) was known to act as effective barrier to the motion of irradiation damage and grain boundaries (GBs). The irradiation response to the He/H synergistic effect and the role of KBs on damage defects were two key issues when evaluating the performance of KW in future fusion reactors. In this work, KW was in-situ irradiated by 30 keV He+ and H 2 + with He/H ratios of 2.5, 0.5, and 0.1 at 823 K. The synergy of He, H, and damage defects were discussed. The number density and the average size of irradiation-induced loops and bubbles nearby KBs, nearby GBs, and within the matrix was quantified. Increasing the ratio of H to He enhanced the nucleation sites of loops and promoted the accumulation rates of bubbles. The formation of a loop denuded zone nearby a KB was related to the KB size. The difference between the loop denuded zones nearby KBs and GBs was found. The estimated sink strengths of KBs and GBs were in line with our experimental results. • Synergy of He/H and damage defects in KW was in-situ investigated firstly. • Effect of K bubble on irradiation damages was studied. • Evolution of loop denuded zones near K bubble and grain boundary was displayed. • Sink strengths of K bubble and grain boundary were evaluated. [ABSTRACT FROM AUTHOR]

The evolution of heavy-ion irradiation induced microstructures, followed by annealing experiments, was analyzed in situ and characterized systematically in tungsten via transmission electron microscopy. The formation and evolution of loop rafts, dislocation decoration, and tangled dislocation networks were analyzed during irradiation. Consisting of 1/2<111> loops, raft structures had a preferred orientation, which was dependent on loop geometry. Decoration of a near-edge line dislocation with loops led the line first to curve and then annihilate. Drastic loss of loops, loop-loop coalescence, glide of jogged line dislocations as well as untangling of dislocation networks were observed during post-annealing. The gliding of glissile loops varied with its size, while the motion of line dislocations depended on their nature. The glide distance for the small loops with a size range from 1 to 3 nm was 6 times larger than the large loops with a size range from 5 to 8 nm. A near-edge dislocation had the largest mobility, a near-screw one had the lowest mobility, and a mixed one had the mobility in between. The direct observation and comprehensive analysis of the complicated interaction among dislocations will offer insights into the bridge between the microstructural evolution and macroscopic response to irradiation damages. • Heavy-ion irradiation and post-irradiation annealing of W were studied in situ. • Raft structures had preferred orientations, which depended on loop geometry. • Decoration process of an edge-character line dislocation by loops was observed. • Annealing caused dislocation networks untangle to line dislocations. • Size affected loop motion, whereas dislocation nature determined line mobility. [ABSTRACT FROM AUTHOR]

The secondary metabolite Monacolin K (MK), derived from Monascus , exhibits potential lipid-lowering and anti-tumor effects. In this study, a mutant strain M. purpureus M400–6 was generated through X-ray treatment, resulting in an average MK production of 181.97 mg/L (a 54.20% increase compared to the parent strain M. purpureus M1) over five successive generations. Furthermore, optimization of medium compositions using response surface methodology led to a further enhancement in MK production by the mutant strain to 266.63 mg/L. Moreover, based on the outcomes of single-factor experiments, the addition of L-citrulline demonstrated a significantly higher level of enhancement in MK production. Therefore, a comparative transcriptome analysis was conducted to unveil the impact of L-citrulline on MK biosynthesis in M. purpureus. The data revealed a significant upregulation of glycolysis pathways, while oxidative phosphorylation including the TCA cycle and the electron transport chain, exhibited significant downregulation. Furthermore, the metabolisms of serine, glycine, threonine, alanine, aspartic acid and glutamate were found to be significantly disturbed. Additionally, the expressions of MPs and MK biosynthetic gene cluster showed a significant downregulation and upregulation respectively. Overall, these findings provide insights into enhancing MK production in submerged fermentation and elucidate the impact of L-citrulline on secondary metabolism. [Display omitted] • M. purpureus M400–6 with high MK production was generated through X-ray treatment. • L-citrulline can significantly enhance the MK production. • Response surface methodology was performed to further increase the MK production. • Transcriptome analysis reveals the impact of L-citrulline on MK biosynthesis. [ABSTRACT FROM AUTHOR]

The evolution of dislocation loops and helium bubbles in W-0.5ZrC alloy with different pre-existing dislocation densities was investigated by in-situ transmission electron microscopy during 30 keV He+ irradiation at 800 °C. The nucleation, migration, aggregation, and growth of dislocation loops and helium bubbles occurred with the whole irradiation process. The variation trends of average size and volume number density of dislocation loops and helium bubbles with the increase of irradiation dose in the regions with different pre-existing dislocation densities were obtained. It was found that the growth of dislocation loops was inhibited in the region with a low pre-existing dislocation density (about 5.2 × 1013 /m2), and the nucleation of dislocation loops was inhibited in the region with the dispersed medium density (about 1.6 × 1014 /m2, dislocations were crossed but dispersed), while both the nucleation and growth of dislocation loops were inhibited in the region with the compact medium density (about 1.5 × 1014 /m2, dislocations were crossed and compact). During the irradiation process, the pre-existing dislocations would interact with the irradiation-induced dislocation loops and helium bubbles, but their influence weakened with the increase of irradiation dose, and finally resulted in the disappearance or deformation of pre-existing dislocations. The irradiation hardening caused by dislocation loops and helium bubbles was increased with the increase of irradiation dose, and the corresponding mechanism was analyzed. [ABSTRACT FROM AUTHOR]

• The evolution of F/M steel during irradiation and annealing was studied by in-situ TEM. • Loop evolution was researched by in-situ TEM in the initial stage of He+ irradiation. • Bubble evolution and shape change during irradiation and annealing were in-situ studied. • Bubble lines formed at the dislocation and large bubbles appeared at the grain boundary. • Denuded zone width decreased with increasing helium fluence and annealing time. The evolution of helium bubbles in a newly developed Fe9Cr1.5W0.4Si alloy that is an important candidate used as fuel claddings in the Lead-cooled fast reactors was in-situ investigated by transmission electron microscopy during 30 keV He+ irradiation at 500 °C and subsequently annealed at 600 °C. Meanwhile, the evolution of dislocation loops was in-situ researched in the initial stage of irradiation. Two mechanisms including the absorption of irradiation defects and the combination of dislocation loops induced the loop growth. Both He+ irradiation and subsequently annealing induced the initiation, migration, aggregation, and growth of helium bubbles, and changed their shape from spherical to preferential faceted. But it was more obvious under the annealing condition. Helium bubbles would preferentially nucleate and grow at dislocation lines and grain boundaries and had large size. The bubble lines formed at dislocation line during helium irradiation, and annealing made them more obvious and larger. A denuded zone with few helium bubbles appeared near grain boundary, but its width decreased with the increase of helium fluence and annealing time. Meanwhile, annealing would lead to the appearance of super large helium bubbles at grain boundaries. The irradiation hardening and swelling were increased with the increase of helium fluence. The corresponding mechanism was analyzed based on in-situ experimental observation. [Display omitted] [ABSTRACT FROM AUTHOR]

Low mobility <100> loops significantly affect the mechanical properties of body-centered cubic materials and their generation and evolution have been a hot research topic recently. However, there is still a lack of direct observation on the reaction of the formed <100> loops during subsequent irradiation, which hinders a better understanding of the degradation of mechanical properties induced by irradiation. Here, we reported for the first time that the reaction between <100> loops produced 1/2<111> loop through in-situ TEM observation during 30 keV H 2 + & He+ dual-beam irradiation in tungsten. Molecular dynamics simulation showed that this reaction required appropriate relative position of the initial <100> loops and high temperature that could induce <100> loop split into 1/2<111> segments and then transformed into 1/2<111> loop. Meanwhile, the evolution of <100> loops was in-situ observed. The average size and areal number density of <100> loops were quantified as a function of irradiation fluence. [ABSTRACT FROM AUTHOR]

Image, graphical abstract In-situ irradiations with 30 keV He+ were performed on tungsten in an investigation of the influences of irradiation temperature and fluence, pre-existing dislocation and sample thickness on dislocation loop evolution including interaction, density and size. Dislocation loops with b = 1/2<111> and b =<100> were found to form in tungsten during irradiation. The ratio of 〈100〉 loops was obviously affected by irradiation temperature, fluence, sample thickness and pre-existing dislocation lines. The interaction between high density helium clusters could stimulate the formation of 〈100〉 loops in irradiated W, which was verified by Molecular Dynamic (MD) simulations. In addition, the driving force for the 〈100〉 loop formation should also be attributed to the reaction of two 1/2<111> loop variants driven by long-time and elevated temperature irradiation. The pre-existing dislocation lines were found to have a profound effect on the size, density and Burgers vector of dislocation loops. Additionally, irradiation-induced defects were likely to be absorbed by the surface sinks of thin foil during ion irradiation, resulting in the formation of a denuded zone near the surface. The in-situ observation of irradiation defect evolution will lead to an improved fundamental understanding of irradiation damage process of tungsten serviced in fusion reactor. [ABSTRACT FROM AUTHOR]