[Objectives] To examine the mechanisms underlying the anti-inflammatory, anti-pruritic, and anti-allergic effects of the Fuyanjie Chinese herbal formula, which comprises Radix Sophorae Flavescentis, Stemonae Radix, Fr...[Objectives] To examine the mechanisms underlying the anti-inflammatory, anti-pruritic, and anti-allergic effects of the Fuyanjie Chinese herbal formula, which comprises Radix Sophorae Flavescentis, Stemonae Radix, Fructus Cnidii, and Phellodendri Chinensis Cortex, on sensitive skin using network pharmacology.[Methods] The TCMSP database was employed to identify and extract the active ingredients and corresponding targets of the Fuyanjie formula. The collective targets were then intersected with the disease targets "pruritus", "dermatitis", and "skin allergy", which were obtained from the GeneCards database, in order to identify the core targets. The String database, Cytoscape software, and the cytoHubba plug-in were utilized to construct and analyze the protein-protein interaction (PPI) network, and the key hub genes were subsequently identified and quantified. A GO function analysis and KEGG enrichment analysis of core action targets were conducted utilizing the DAVID database.[Results] A total of 87 active ingredients were identified from the Fuyanjie formula through a screening process, which corresponded to a total of 254 targets of action. Through intersection analysis, 41 core targets of the Fuyanjie Chinese herbal formula were identified, which contribute to its anti-inflammatory, anti-pruritic, and anti-allergic effects. The findings indicated that quercetin, beta-sitosterol, stigmasterol, formononetin, luteolin, and other bioactive compounds present in the Fuyanjie Chinese herbal formula may interact with the targets IL-6, MMP-9, TNF, and IL-1β. These compounds were suggested to exert anti-inflammatory, anti-pruritic, and anti-allergic effects through pathways associated with the inflammatory response, including the IL-17 signaling pathway, TNF signaling pathway, NF-κB signaling pathway, etc.[Conclusions] Fuyanjie Chinese herbal formula may modulate skin conditions through a multifaceted mechanism of action that involves multiple components, targets, and pathways.展开更多
Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sarga...Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum gramini- folium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.展开更多
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer...Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.展开更多
The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmiss...The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms.These findings were discussed with the local strain measurements via digital image correlation.The results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of yielding.The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier effect.The volume fraction of RA gradually decreased from 26.8%to 8.2%prior to fracture.In the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.展开更多
van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type phot...van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered mode.Herein,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly.The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction.Notably,the strain-tunable photodetection performances of device have been demonstrated.Impressively,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible photodetectors.This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors.展开更多
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c...The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics.展开更多
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac...Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines.展开更多
BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity va...BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically.展开更多
Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads ...Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics.The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation.Based on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established.The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition.In contrast,an increase in altitude accelerated the propagation speed of the shock wave in the tunnel.The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.展开更多
BACKGROUND Routinely separating the ligamentum teres uteri(LTU)intraoperatively remains an unresolved issue for female children undergoing surgery for indirect inguinal hernia(IIH).AIM To identify the effect of LTU pr...BACKGROUND Routinely separating the ligamentum teres uteri(LTU)intraoperatively remains an unresolved issue for female children undergoing surgery for indirect inguinal hernia(IIH).AIM To identify the effect of LTU preservation in laparoscopic high hernia sac ligation(LHSL)in children with IIH.METHODS The participants were 100 female children with unilateral IIH admitted from April 2022 to January 2024 to the Pediatric Surgery Department of Zhangzhou Municipal Hospital of Fujian Province.They were categorized based on LTU retention into the control group(n=45 cases),which underwent LTU ligation intraoperatively,and the experimental group(55 cases),which had the LTU preserved intraoperatively.All children underwent LHSL.RESULTS This study comparatively analyzed the operation time,hospitalization time,blood loss,postoperative recurrence rate,and complications(repeated pain in the inguinal region,foreign body sensation in the inguinal region,bloody exudation at the inguinal incision,and incision infection),which were all comparable between the two groups.CONCLUSION The above results indicate that LTU preservation during LHSL exerts certain therapeutic benefits for children with IIH.LTU preservation does not increase hospitalization time,blood loss,postoperative recurrence rate,and complications,which is safe and feasible,compared with conventional LTU ligation.LHSL with LTU preservation should be performed if conditions permit,which is worth popularizing.展开更多
[Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracte...[Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracted. Effects of extraction conditions including extraction temperature, ethanol concentration, extraction time and liquid-to-solid ratio on extraction were explored with single-factor experiment, and the extrac- tion process was optimized with orthogonal experiment. [Result] Based on the single- factor experiment and orthogonal experiment, the optimal extraction condition for crude anti-allergic active extracts of citrus peels were determined to be under extraction temperature of 60℃, ethanol concentration of 70%, extraction time of 60 min, liquid-to-solid ratio of 1:25 and twice extraction. [Concluslon] This process condition is of simple operation and high extraction efficiency, which is environment-friendly and suitable for the extraction of crude anti-allergic active extracts from citrus peels. This study provided a new approach and research ideas for the effective and rapid extraction of anti-allergic active ingredient in citrus peels.展开更多
Natural polyphenol has been widely believed to be effective in allergy remission. Currently, most of the natural poly- phenol products come from terrestrial sources such as tea, grape seeds among others, and few polyp...Natural polyphenol has been widely believed to be effective in allergy remission. Currently, most of the natural poly- phenol products come from terrestrial sources such as tea, grape seeds among others, and few polyphenols have been developed from algae for their anti-allergic activity. The aim of the study was to screen some commercial seaweed for natural extracts with anti-al- lergic activity. Five algae including Laminaria japonica, Porphyra sp., Spirulina platensis, Chlorella pyrenoidosa and Scytosiphon sp were extracted with ethanol, and the extracts were evaluated for total polyphenol contents and anti-allergic activity with the hyalu- ronidase inhibition assay. Results showed that the total polyphenol contents in the ethanol extracts ranged from 1.67% to 8.47%, while the highest was found in the extract from Scytosiphon sp. Hyaluronidase inhibition assay showed that the extracts from Scyto- siphon sp. had the lowest IC50, 0.67 mg mL-1, while Chlorella pyrenoidosa extract had the highest IC50, 15.07 mg mL-1. The anti-allergic activity of Scytosiphon sp. extract was even higher than the typical anti-allergic drug Disodium Cromoglycate (DSCG) (IC50=1.13 mg mL-1), and was similar with natural polyphenol from Epigallocatechin gallate (EGCG) (IC50 = 0.56 mg mL-l). These results indicated that the ethanol extract of Scytosiphon sp. contains a high concentration of polyphenol with high anti-allergic activ- ity. Potentially Scytosiphon sp. can be developed to a natural anti-allergic compound for allergy remission.展开更多
The production of β-maltooligosaccharides of capsaicin was investigated using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase) as biocatalysts. The cells of L. delbrueckii glucosylated capsaicin...The production of β-maltooligosaccharides of capsaicin was investigated using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase) as biocatalysts. The cells of L. delbrueckii glucosylated capsaicin to give its β-glucoside. The β-glucoside of capsaicin was converted into the corresponding β-maltoside and β-maltotrioside by CGTase. On the other hand, β-melibioside and β-isomaltoside of capsaicin, which were two new compounds, were synthesized by chemical glycosylation. The β-glucoside, β-maltoside, β-melibioside, and β-isomaltoside of capsaicin showed inhibitory effects on IgE antibody production.展开更多
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef...240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs.展开更多
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect...Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries.展开更多
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat...Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.展开更多
Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Ta...Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth.展开更多
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ...To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.展开更多
The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fou...The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.展开更多
Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency a...Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe_(2) vertical heterostructure where the WSe_(2) layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe_(2), as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×10~4A/W and external quantum efficiency of 1.3 × 10~7%.This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices.展开更多
基金Supported by Shanghai Putuo District Science and Technology R&D Platform Project(2024QX04).
文摘[Objectives] To examine the mechanisms underlying the anti-inflammatory, anti-pruritic, and anti-allergic effects of the Fuyanjie Chinese herbal formula, which comprises Radix Sophorae Flavescentis, Stemonae Radix, Fructus Cnidii, and Phellodendri Chinensis Cortex, on sensitive skin using network pharmacology.[Methods] The TCMSP database was employed to identify and extract the active ingredients and corresponding targets of the Fuyanjie formula. The collective targets were then intersected with the disease targets "pruritus", "dermatitis", and "skin allergy", which were obtained from the GeneCards database, in order to identify the core targets. The String database, Cytoscape software, and the cytoHubba plug-in were utilized to construct and analyze the protein-protein interaction (PPI) network, and the key hub genes were subsequently identified and quantified. A GO function analysis and KEGG enrichment analysis of core action targets were conducted utilizing the DAVID database.[Results] A total of 87 active ingredients were identified from the Fuyanjie formula through a screening process, which corresponded to a total of 254 targets of action. Through intersection analysis, 41 core targets of the Fuyanjie Chinese herbal formula were identified, which contribute to its anti-inflammatory, anti-pruritic, and anti-allergic effects. The findings indicated that quercetin, beta-sitosterol, stigmasterol, formononetin, luteolin, and other bioactive compounds present in the Fuyanjie Chinese herbal formula may interact with the targets IL-6, MMP-9, TNF, and IL-1β. These compounds were suggested to exert anti-inflammatory, anti-pruritic, and anti-allergic effects through pathways associated with the inflammatory response, including the IL-17 signaling pathway, TNF signaling pathway, NF-κB signaling pathway, etc.[Conclusions] Fuyanjie Chinese herbal formula may modulate skin conditions through a multifaceted mechanism of action that involves multiple components, targets, and pathways.
基金Project supported by the Hi-Tech Research and Development Program(863)of China(No.2006AA09Z427)the National Natural Science Foundation of China(Nos.30800859 and 30871948)
文摘Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum gramini- folium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.
基金supported by the Shenzhen Science and Technology Program(JCYJ20230808105111022,JCYJ20220818095806013)Natural Science Foundation of Guangdong(2023A1515012267)+1 种基金the National Natural Science Foundation of China(22178223)the Royal Society/NSFC cost share program(IEC\NSFC\223372).
文摘Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.
基金supported by the National Key R&D Program of China(No.2017YFB0304402)。
文摘The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms.These findings were discussed with the local strain measurements via digital image correlation.The results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of yielding.The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier effect.The volume fraction of RA gradually decreased from 26.8%to 8.2%prior to fracture.In the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.
基金supported by the National Key Research and Development Program of China(No.2022YFB3604500,No.2022YFB3604501)the National Natural Science Foundation of China(No.52172141)the Technology Development Project of Shanxi-Zheda Institude of Advanced Materials and Chemical Engineering(No.2022SX-TD017).
文摘van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered mode.Herein,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly.The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction.Notably,the strain-tunable photodetection performances of device have been demonstrated.Impressively,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible photodetectors.This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors.
文摘The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics.
基金funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan(Grant No.AP19680589).
文摘Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines.
基金Supported by Science and Technology Innovation 2030-Major Projects,No.2021ZD0202000National Key Research and Development Program of China,No.2019YFA0706200+2 种基金National Natural Science Foundation of China,No.82371535Science and Technology Innovation Program of Hunan Province,No.2023RC3083Fundamental Research Funds for the Central Universities of Central South University,No.2023ZZTS0838.
文摘BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically.
基金financially supported by National Natural Science Foundation of China(Grant Nos.52378401,52278504)the Fundamental Research Funds for the Central Universities(Grant No.30922010918)。
文摘Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics.The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation.Based on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established.The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition.In contrast,an increase in altitude accelerated the propagation speed of the shock wave in the tunnel.The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.
基金Supported by the Startup Fund for Scientific Research,Fujian Medical University,No.2021QH1262.
文摘BACKGROUND Routinely separating the ligamentum teres uteri(LTU)intraoperatively remains an unresolved issue for female children undergoing surgery for indirect inguinal hernia(IIH).AIM To identify the effect of LTU preservation in laparoscopic high hernia sac ligation(LHSL)in children with IIH.METHODS The participants were 100 female children with unilateral IIH admitted from April 2022 to January 2024 to the Pediatric Surgery Department of Zhangzhou Municipal Hospital of Fujian Province.They were categorized based on LTU retention into the control group(n=45 cases),which underwent LTU ligation intraoperatively,and the experimental group(55 cases),which had the LTU preserved intraoperatively.All children underwent LHSL.RESULTS This study comparatively analyzed the operation time,hospitalization time,blood loss,postoperative recurrence rate,and complications(repeated pain in the inguinal region,foreign body sensation in the inguinal region,bloody exudation at the inguinal incision,and incision infection),which were all comparable between the two groups.CONCLUSION The above results indicate that LTU preservation during LHSL exerts certain therapeutic benefits for children with IIH.LTU preservation does not increase hospitalization time,blood loss,postoperative recurrence rate,and complications,which is safe and feasible,compared with conventional LTU ligation.LHSL with LTU preservation should be performed if conditions permit,which is worth popularizing.
基金Supported by Analysis and Testing Technology Program of Zhejiang Science and Technology Agency (2007F70027)Xinmiao Talent Program of Zhejiang Province(2008R40G2080020)Hangzhou Science and Technology Program (20091832B50,20101032B18)~~
文摘[Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracted. Effects of extraction conditions including extraction temperature, ethanol concentration, extraction time and liquid-to-solid ratio on extraction were explored with single-factor experiment, and the extrac- tion process was optimized with orthogonal experiment. [Result] Based on the single- factor experiment and orthogonal experiment, the optimal extraction condition for crude anti-allergic active extracts of citrus peels were determined to be under extraction temperature of 60℃, ethanol concentration of 70%, extraction time of 60 min, liquid-to-solid ratio of 1:25 and twice extraction. [Concluslon] This process condition is of simple operation and high extraction efficiency, which is environment-friendly and suitable for the extraction of crude anti-allergic active extracts from citrus peels. This study provided a new approach and research ideas for the effective and rapid extraction of anti-allergic active ingredient in citrus peels.
基金financially supported by Shandong Province Young and Middle-Aged Scientists Research Awards Fund(BS2011HZ020)the National Natural Science Foundation of China(No.31371730)Program for Changjiang Scholars and Innovative Research Team in University
文摘Natural polyphenol has been widely believed to be effective in allergy remission. Currently, most of the natural poly- phenol products come from terrestrial sources such as tea, grape seeds among others, and few polyphenols have been developed from algae for their anti-allergic activity. The aim of the study was to screen some commercial seaweed for natural extracts with anti-al- lergic activity. Five algae including Laminaria japonica, Porphyra sp., Spirulina platensis, Chlorella pyrenoidosa and Scytosiphon sp were extracted with ethanol, and the extracts were evaluated for total polyphenol contents and anti-allergic activity with the hyalu- ronidase inhibition assay. Results showed that the total polyphenol contents in the ethanol extracts ranged from 1.67% to 8.47%, while the highest was found in the extract from Scytosiphon sp. Hyaluronidase inhibition assay showed that the extracts from Scyto- siphon sp. had the lowest IC50, 0.67 mg mL-1, while Chlorella pyrenoidosa extract had the highest IC50, 15.07 mg mL-1. The anti-allergic activity of Scytosiphon sp. extract was even higher than the typical anti-allergic drug Disodium Cromoglycate (DSCG) (IC50=1.13 mg mL-1), and was similar with natural polyphenol from Epigallocatechin gallate (EGCG) (IC50 = 0.56 mg mL-l). These results indicated that the ethanol extract of Scytosiphon sp. contains a high concentration of polyphenol with high anti-allergic activ- ity. Potentially Scytosiphon sp. can be developed to a natural anti-allergic compound for allergy remission.
文摘The production of β-maltooligosaccharides of capsaicin was investigated using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase) as biocatalysts. The cells of L. delbrueckii glucosylated capsaicin to give its β-glucoside. The β-glucoside of capsaicin was converted into the corresponding β-maltoside and β-maltotrioside by CGTase. On the other hand, β-melibioside and β-isomaltoside of capsaicin, which were two new compounds, were synthesized by chemical glycosylation. The β-glucoside, β-maltoside, β-melibioside, and β-isomaltoside of capsaicin showed inhibitory effects on IgE antibody production.
基金This work was supported by National Key R&D Program of China(2022YFB3605103)the National Natural Science Foundation of China(62204241,U22A2084,62121005,and 61827813)+3 种基金the Natural Science Foundation of Jilin Province(20230101345JC,20230101360JC,and 20230101107JC)the Youth Innovation Promotion Association of CAS(2023223)the Young Elite Scientist Sponsorship Program By CAST(YESS20200182)the CAS Talents Program(E30122E4M0).
文摘240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs.
基金support from the “Joint International Laboratory on Environmental and Energy Frontier Materials”“Innovation Research Team of High-Level Local Universities in Shanghai”support from the National Natural Science Foundation of China (22209103)
文摘Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries.
基金financially supported by the National Key Research and Development Program of China(2021YFD2100904)the National Natural Science Foundation of China(31871729,32172147)+2 种基金the Modern Agriculture key Project of Jiangsu Province of China(BE2022317)the Modern Agricultural Industrial Technology System Construction Project of Jiangsu Province of China(JATS[2021]522)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.
基金supported by the National Natural Science Foundation of China(Grant No.42077244).
文摘Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth.
基金The financial support from the National Natural Science Foun-dation of China(Grant Nos.52074299 and 41941018)the Fundamental Research Funds for the Central Universities of China(Grant No.2023JCCXSB02)are gratefully acknowledged.
文摘To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.
基金supported by the National Natural Science Foundation of China(Nos.12022515 and 11975304)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.Y202063)。
文摘The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.
基金Project supported by the National Natural Science Foundation of China (Grant No.11974379)the National Key Basic Research and Development Program of China (Grant No.2021YFC2203400)Jiangsu Vocational Education Integrated Circuit Technology “Double-Qualified” Famous Teacher Studio (Grant No.2022-13)。
文摘Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe_(2) vertical heterostructure where the WSe_(2) layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe_(2), as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×10~4A/W and external quantum efficiency of 1.3 × 10~7%.This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices.