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Palladium (Pd) catalysts play a crucial role in facilitating Suzuki cross-coupling reactions for the synthesis of valuable organic compounds. However, conventional heterogeneous Pd catalysts often encounter challenges such as leaching and deactivation during reactions, leading to reduced catalytic efficiency. In this study, we employed an innovative intercalation templating strategy to prepare two-dimensional carbon nanosheets with high nitrogen doping derived from petroleum asphalt, which were utilized as a versatile support for immobilizing Pd nanoparticles (Pd/N-CNS) in efficient Suzuki cross-coupling reactions. The results indicate that the anchoring effect of high-pyridinic N species on the two-dimensional carbon nanosheets enhances interactions between Pd and the support, effectively improving both the dispersibility and stability of the Pd nanoparticles. Notably, the Pd/N-CNS catalyst achieved an overall turnover frequency (TOF) of 2390 h−1 for the Suzuki cross-coupling reaction under mild conditions, representing approximately a nine-fold increase in activity compared to commercial Pd/C catalysts. Furthermore, this catalyst maintained an overall TOF of 2294 h−1 even after five reaction cycles, demonstrating excellent stability. Theoretical calculations corroborate these observed enhancements in catalytic performance by attributing them to improved electron transfer from Pd to the support facilitated by abundant pyridinic N species. This work provides valuable insights into feasible strategies for developing efficient catalysts aimed at sustainable production of biaromatic compounds.

Abstract Developing efficient metal‐nitrogen‐carbon (M‐N‐C) single‐atom catalysts for oxygen reduction reaction (ORR) is significant for the widespread implementation of Zn‐air batteries, while the synergic design of the matrix microstructure and coordination environment of metal centers remains challenges. Herein, a novel salt effect‐induced strategy is proposed to engineer N and P coordinated atomically dispersed Fe atoms with extra‐axial Cl on interlinked porous carbon nanosheets, achieving a superior single‐atom Fe catalyst (denoted as Fe‐NP‐Cl‐C) for ORR and Zn‐air batteries. The hierarchical porous nanosheet architecture can provide rapid mass/electron transfer channels and facilitate the exposure of active sites. Experiments and density functional theory (DFT) calculations reveal the distinctive Fe‐N2P2‐Cl active sites afford significantly reduced energy barriers and promoted reaction kinetics for ORR. Consequently, the Fe‐NP‐Cl‐C catalyst exhibits distinguished ORR performance with a half‐wave potential (E1/2) of 0.92 V and excellent stability. Remarkably, the assembled Zn‐air battery based on Fe‐NP‐Cl‐C delivers an extremely high peak power density of 260 mW cm−2 and a large specific capacity of 812 mA h g−1, outperforming the commercial Pt/C and most reported congeneric catalysts. This study offers a new perspective on structural optimization and coordination engineering of single‐atom catalysts for efficient oxygen electrocatalysis and energy conversion devices.

Chinese cities are pursuing an energy transition to decouple energy-related carbon emissions (ERCEs) from economic growth. Despite numerous studies focusing on the factors influencing carbon emissions, few have quantitatively analyzed their respective contribution rates, thus leaving a gap in effectively guiding policies. This study took 16 cities in the Yangtze River Delta (YRD) as the study area. The decoupling between ERCEs and economic growth was analyzed during 2000–2020, and the contribution rates of different factors were explored. The results showed that the total ERCEs increased from 413.40 million to 1265.86 million tons during 2000–2020, increasing by over three times. Coal and oil were the dominant energy sources in most cities, but natural gas consumption increased from 0.15% to 5.96%. Moreover, 14 cities showed a decoupling status, indicating a certain win–win situation between economic growth and ERCE reduction. Economic growth greatly increased ERCEs, with its contribution rate ranging from 114.65% to 493.27% during 2000–2020. On the contrary, energy structure and energy intensity both contributed to reducing ERCEs in most cities, and their maximum contribution rates reached −32.29% and −449.13%, respectively, which were the main forces for the win–win situation. Finally, carbon reduction proposals are put forward, which provide theoretical support for achieving the “Double Carbon” goal in the YRD.

Formic acid has emerged as a highly promising hydrogen storage material, and the development of efficient catalysts to facilitate its dehydrogenation remains imperative. In this study, a novel catalyst consisting of palladium nanoparticles supported on boron-doped porous carbon (Pd/BPC) was successfully synthesized to enable efficient hydrogen production through the dehydrogenation of formic acid. The impacts of the boron doping ratio, doping temperature, and palladium reduction temperature on the catalyst’s performance were systemically investigated. The results demonstrated the Pd/BPC catalyst synthesized with a carbon-to-boron ratio of 1:5 by calcination at 900 °C and subsequent reduction at 60 °C exhibited superior formic acid dehydrogenation performance, being 2.9 and 3.8 times greater than that of the Pd/PC catalysts without boron doping and commercial Pd/C, respectively. Additionally, the catalyst showed excellent cycle stability with no significant activity reduction after five consecutive cycles. Experimental and theoretical results reveal that boron doping not only facilitates the homogenous distribution of Pd nanoparticles but also induces a stronger support–metal interaction, thereby reinforcing the catalytic performance. This research is expected to provide valuable insights into the economically viable and efficient production of environmentally friendly hydrogen energy.

Summary: In birds, little is known about how individuals choose nest sites based on their personality traits. Here, we investigate whether a female’s personality (activity and breathing rate) can affect patterns of nest site selection at different spatial scales in a wild population of chestnut thrush (Turdus rubrocanus) and determine whether nest site characteristics and female personality traits affect clutch size and nest success during incubation. We found that neither activity nor breathing rate were associated with large-scale nesting habitat variables. At the fine-scale level, more active females chose nest sites with greater nest lateral concealment. Females with higher breathing rates laid smaller clutch sizes than individuals with lower breathing rates. Nests of females with lower breathing rate had higher nest success during incubation. This work highlights the relationships between personality and nest site selection in birds, and the important role of female personality traits in reproductive success.

Abstract Dispersal affects the spatial distribution and population structure of species. Dispersal is often male‐biased in mammals while female‐biased in birds, with the notable exception of the Anatidae. In this study, we tested genetic evidence for sex‐biased dispersal (SBD) in the Swan Goose Anser cygnoides, an Asian endemic and IUCN vulnerable species, which has been increasingly restricted to breeding on Mongolian steppe wetlands. We analyzed the genotypes of 278 Swan Geese samples from 14 locations at 14 microsatellite loci. Results from assignment indices, analysis of molecular variance, and five other population descriptors all failed to support significant SBD signals for the Swan Goose at the landscape level. Although overall results showed significantly high relatedness within colonies (suggesting high levels of philopatry in both sexes), local male genetic structure at the 1,050 km distance indicated greater dispersal distance for females from the eastern sector of the breeding range. Hence, local dispersal is likely scale‐dependent and female‐biased within the eastern breeding range. These findings are intriguing considering the prevailing expectation for there to be female fidelity in most goose species. We suggest that while behavior‐related traits may have facilitated the local genetic structure for the Swan Goose, several extrinsic factors, including the decreasing availability of the nesting sites and the severe fragmentation of breeding habitats, could have contributed to the absence of SBD at the landscape level. The long‐distance molt migration that is typical of goose species such as the Swan Goose may also have hampered our ability to detect SBD. Hence, we urge further genetic sampling from other areas in summer to extend our results, complemented by field observations to confirm our DNA analysis conclusions about sex‐specific dispersal patterns at different spatial scales in this species.

Abstract Background The Oriental Stork (Ciconia boyciana) breeds in southeastern Siberia and parts of northeast China, and winters mainly in southeast China. Although the autumn migration pattern of Oriental Storks has been previously described, differences between spring and autumn migration travel speed in relation to wind assistance were unknown. Methods Using GPS/GSM transmitters, we tracked the full migrations of 18 Oriental Storks during 2015‒2018 to compare differences in autumn and spring migration patterns, and combined the satellite telemetry data with the National Center for Environmental Prediction Reanalysis data to explain the relationship between 850 mbar wind vectors and seasonal differences in travel speed. Results Differences in tailwinds contributed to significant differences in daily average Oriental Storks travel speed in spring (258.11 ± 64.8 km/day) compared to autumn (172.23 ± 49.7 km/day, p

Sex differences in plumage color are common in bird species. Some bird species are regarded as sexually monochromatic in human visual systems, and in recent years, some species are found to be of cryptic (to human) sexual dichromatism by spectrophotometric techniques. However, the functions of plumage color are still less understood in these species. Here, we focused on plumage color traits in the Chestnut Thrush (Turdus rubrocanus), which is considered as a sexually monochromatic bird by human observers. We used spectrometer analyses and avian visual modeling to investigate the color traits of males and females, and whether these color traits are involved in assortative mating. We found that Chestnut Thrush showed sexual dichromatism in bill, throat and wing, and pairs mated assortatively with colorations of throat, chest, crown and wing. We also found that color of tarsus was different between two consecutive years. These results revealed that Chestnut Thrush is sexually dichromatic in the avian visual system, and plumage color traits play important roles in mate choice.

Sympatric Chinese-wintering Eastern Tundra Bean Geese (Anser fabalis serrirostris, ETBG) breed in two widely separated Arctic areas (Central Russian Arctic and Anadyr region); South Korean-wintering birds (Chaun-South Korea) breed in a third discrete area between these two. Such winter/summer segregation likely structures the population, potentially resulting in distinct migration patterns and habitat-use throughout the annual cycle. We tracked individuals using GPS-GSM transmitters from all three of these geographically discrete ETBG subpopulations to see whether this was the case, testing for differences in migration patterns, seasonal and diurnal habitat-use using remotely sensed land-cover mapping. Mean migration distance of Central Arctic-China and Chaun-South Korea individuals did not differ significantly, but Anadyr-China birds travelled 15–24% further (mean: 1140 ​km, P ​

This study investigated the changes in the structure and properties of soybean protein after hydrolysis using two types of hybrid nanoflowers (alcalase@Cu3(PO4)2•3H2O (ACHNs) and dispase@Cu3(PO4)2•3H2O (DCHNs)) and examined the basic properties and oxidative stability of hydrolyzed soybean protein emulsions. The formations of the two hybrid nanoflowers were first determined using a scanning electron microscope, transmission electron microscope, and Fourier infrared spectroscopy. The structure and functional properties of soybean protein treated with hybrid nanoflowers were then characterized. The results indicated that the degree of hydrolysis (DH) of the ACHNs hydrolysates was higher than that of the DCHNs for an identical reaction time. Soybean protein hydrolysates treated with two hybrid nanoflowers showed different fluorescence and circular dichroism spectra. The solubility of the hydrolysates was significantly higher (p < 0.05) than that of the soybean protein (SPI) at all pH values tested (2.0–10.0)*: at the same pH value, the maximum solubility of ACHNs hydrolysates and DCHNs hydrolysates was increased by 46.2% and 42.2%, respectively. In addition, the ACHNs hydrolysates showed the highest antioxidant activity (DPPH IC50 = 0.553 ± 0.009 mg/mL, ABTS IC50 = 0.219 ± 0.019 mg/mL, and Fe2+ chelating activity IC50 = 40.947 ± 3.685 μg/mL). The emulsifying activity index of ACHNs and DCHNs hydrolysates reached its maximum after hydrolysis for 120 min at 61.38 ± 0.025 m2/g and 54.73 ± 0.75 m2/g, respectively. It was concluded that the two hydrolysates have better solubility and antioxidant properties, which provides a theoretical basis for SPI product development. More importantly, the basic properties and oxidative stability of the soybean-protein-hydrolysates oil-in-water emulsions were improved. These results show the importance of proteins hydrolyzed by hybrid nanoflowers as emulsifiers and antioxidants in the food and pharmaceutical industry.

Abstract Background Migration theory suggests, and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success, long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn. Methods Using GPS/GSM transmitters, we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic, to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population. Results We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ± 7 days). This difference in migration duration was mainly determined by significantly more time spent in spring (59 ± 16 days) than in autumn (23 ± 6 days) at significantly more stopover sites. Conclusions We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration. In autumn, they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring.

Epidemiological dynamics is a vital method in studying the spread of computer network viruses. In this paper, an optimal control measure is proposed based on the SEIR virus propagation model in point-to-group information networks. First, considering the need for antivirus measures in reality, an optimal control problem is introduced, and then a controlled computer virus spread model in point-to-group information networks is established. Second, the optimal control measure is formulated by making a tradeoff between control cost and network loss caused by virus intrusion. Third, optimal control strategies are theoretically investigated by Pontryagin’s maximum principle and the Hamiltonian function. Finally, through numerical simulations, effective measures for controlling virus spread in point-to-group information networks are proposed.

In order to solve the problems of security threats on workflow scheduling in cloud computing environments, the security of tasks and virtual machine resources are quantified using a cloud model, and the users’ satisfaction degree with the security of tasks assigned to the virtual resources is measured through the similarity of the security cloud. On this basis, combined with security, completion time and cost constraints, an optimized cloud workflow scheduling algorithm is proposed using a discrete particle swarm. The particle in the particle swarm indicates a different cloud workflow scheduling scheme. The particle changes its velocity and position using the evolution equation of the standard particle swarm algorithm, which ensures that it is a feasible solution through the feasible solution adjustment strategies. The simulation experiment results show that the algorithm has better comprehensive performance with respect to the security utility, completion time, cost and load balance compared to other similar algorithms.

The effect of (−)-epigallocatechin-3-gallate (EGCG) on protein structure and emulsion properties of glycosylated black bean protein isolate (BBPI-G) were studied and compared to native black bean protein isolate (BBPI). The binding affinity of BBPI and BBPI-G with EGCG belonged to non-covalent interaction, which was determined by fluorescence quenching. EGCG attachment caused more disordered protein conformation, leading to a higher emulsification property. Among the different EGCG concentrations (0.10, 0.25, 0.50 mg/mL), the result revealed that the highest level of the emulsification property was obtained with 0.25 mg/mL EGCG. Therefore, the BBPI-EGCG and BBPI-G-EGCG prepared by 0.25 mg/mL EGCG were selected to fabricate oil-in-water (O/W) emulsions. After the addition of EGCG, the mean particle size of emulsions decreased with the increasing absolute value of zeta-potential, and more compact interfacial film was formed due to the higher percentage of interfacial protein adsorption (AP%). Meanwhile, EGCG also significantly reduced the lipid oxidation of emulsions.

Developing efficient catalysts with good recyclability is of great importance for its practical applications. In this study, a novel magnetically retrievable nanocomposite (Au-SiO2@Fe3O4-RGO) was synthesized for catalyzing hydration reaction. Active Au nanoparticles are deposited on core-shell SiO2@Fe3O4, which are further supported by a two-dimensional reduced graphene oxide (RGO) platform. The prepared Au-SiO2@Fe3O4-RGO was proven to be efficient as well as recyclable. An excellent catalytic performance, with 97% yield towards the hydration of phenylacetylene, was achieved for the catalyst in dioxane. Remarkably, the catalyst can be readily recycled through magnetic separation and achieved superior catalyst recovery and stability after seven cycles without any metal leaching. This work provides a strategy to fabricate recyclable and durable catalysts for industrial applications.

The conjugates of black bean protein isolate (BBPI) and glucose (G) were prepared via the wet heating Maillard reaction with ultrasound pretreatment. The physicochemical properties of UBBPI-G conjugates prepared by ultrasound pretreatment Maillard reaction had been compared with classical Maillard reaction (BBPI-G). The reaction rate between BBPI and glucose was speeded up by ultrasound pretreatment. A degree of glycation (DG) of 20.49 was achieved by 2 h treatment for UBBPI-G, whereas 5 h was required using the classical heating. SDS-PAGE patterns revealed that the BBPI-G conjugates with higher molecular weight were formed after glycosylation. The results of secondary structure analysis suggested that the α-helix and β-sheet content of UBBPI-G were lower than that of BBPI-G. In addition, UBBPI-G conjugates had exhibited bathochromic shift compared with BBPI by fluorescence spectroscopy analysis. Finally, UBBPI-G achieved higher level of surface hydrophobicity, solubility, emulsification property and antioxidant activity than BBPI and BBPI-G (classical Maillard reaction).

The establishment of sown pasture is an important agricultural practice in many landscapes. Although both native grassland and sown pasture play a key role in the global carbon cycle, due to lack of data and field experiments, our understanding of grassland CH4 fluxes and CO2 emissions remains limited, especially when it comes to sown pasture. We measured ecosystem respiration and CH4 fluxes in response to a variety of potential drivers (soil temperature, soil moisture, ammonium nitrogen, nitrate nitrogen and dissolved organic carbon) in CG (continuous grazing), RG (rotational grazing) and UG (ungrazed) plots in sown grassland for one year in Inner Mongolia. Fluxes of CH4 and ecosystem respiration were measured using static opaque chambers and gas chromatography. Grazing significantly reduced ecosystem respiration (p < 0.01), and grazing pattern significantly influenced respiration in CG and RG plots (p < 0.01). We find that the sown grassland is a net sink for atmospheric CH4. No influence of grazing pattern was observed on CH4 flux in CG, RG and UG (p > 0.05). Soil temperature is the most important factor influencing ecosystem respiration and CH4 flux in the sown grassland, with soil moisture playing a secondary role to soil temperature. Variation in levels of ammonium nitrogen, nitrate nitrogen and dissolved organic carbon had little influence on ecosystem respiration or CH4 flux (except in UG plots). The values obtained for ecosystem respiration of grasslands have a large uncertainty range, which may be due to spatial variability as well as differences in research methods. Mean CH4 fluxes measured only during the growing season were much higher than the annual mean CH4 fluxes.

Understanding the mechanism of plant morphological plasticity in response to grazing and clipping of semiarid grassland can provide insight into the process of disturbance-induced decline in grassland productivity. In recent studies there has been controversy regarding two hypotheses: 1) grazing avoidance; and 2) growth limiting mechanisms of morphological plasticity in response to defoliation. However, the experimental evidence presented for the memory response to grazing and clipping of plants has been poorly reported. This paper reports on two experiments that tested these hypotheses in field and in a controlled environment, respectively. We examined the effects of long-term clipping and grazing on the functional traits and their plasticity for Leymus chinensis (Trin.) Tzvelev (the dominate species) in the typical-steppe grassland of Inner Mongolia, China. There were four main findings from these experiments. (i) The majority of phenotypic traits of L. chinensis tended to significantly miniaturize in response to long-term field clipping and grazing. (ii) The significant response of morphological plasticity with and without grazing was maintained in a hydroponic experiment designed to remove environmental variability, but there was no significant difference in L. chinensis individual size traits for the clipping comparison. (iii) Plasticity indexes of L. chinensis traits in a controlled environment were significantly lower than under field conditions indicating that plants had partial and slight memory effect to long-term grazing. (iv) The allometry of various phenotypic traits, indicated significant trade-offs between leaf and stem allocation with variations in plant size induced by defoliation, which were maintained only under grazing in the hydroponic controlled environment experiment. Taken together, our findings suggest that the morphological plasticity of L. chinensis induced by artificial clipping was different with that by livestock grazing. The miniaturization of plant size in long-term grazed grassland may reflect retained characteristics of dwarf memory for adaptation to long-term grazing by large herbivores.

Peer-to-peer (P2P) botnets have emerged as one of the serious threats to Internet security. To prevent effectively P2P botnet, in this paper, a mathematical model which combines the scale-free trait of Internet with the formation of P2P botnet is presented. Explicit mathematical analysis demonstrates that the model has a globally stable endemic equilibrium when infection rate is greater than a critical value. Meanwhile, we find that, in scale-free network, the critical value is very little. Hence, it is unrealistic to completely dispel the P2P botnet. Numerical simulations show that one can take effective countermeasures to reduce the scale of P2P botnet or delay its outbreak. Our findings can provide meaningful instruction to network security management.