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Heteroatoms Synergistic Anchoring Vacancies in Phosphorus-Doped CoSe_(2)Enable Ultrahigh Activity and Stability in Li-S Batteries
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作者 Xiaoya Zhou Wei Mao +4 位作者 Chengwei Ye Qi Liang Peng Wang Xuebin Wang Shaochun Tang 《Nano-Micro Letters》 2025年第12期305-318,共14页
Electrocatalyst activity and stability demonstrate a“seesaw”relationship.Introducing vacancies(Vo)enhances the activity by improving reactant affinity and increasing accessible active sites.However,deficient or exce... Electrocatalyst activity and stability demonstrate a“seesaw”relationship.Introducing vacancies(Vo)enhances the activity by improving reactant affinity and increasing accessible active sites.However,deficient or excessive Vo reduces polysulfide adsorption and lowers catalytic stability.Herein,a novel“heteroatoms synergistic anchoring vacancies”strategy is proposed to address the trade-off between high activity and stability.Phosphorus-doped CoSe_(2)with remained rich selenium vacancies(P-CS-Vo-0.5)was synthesized by producing abundant selenium Vo followed by controlled P atom doping.Atomic-scale microstructure analysis elucidated a dynamic process of surface vacancy generation and the subsequent partial occupation of these vacancies by P atoms.Density functional theory simulations and in situ Raman tests revealed that the Se vacancies provide highly active catalytic sites,accelerating polysulfide conversion,while P incorporation effectively reduces the surface energy of Se vacancies and suppresses their inward migration,enhancing structural robustness.The battery with the optimal P-CS-Vo-0.5 separator delivers an initial discharge capacity of 1306.7 mAh g^(-1)at 0.2C,and maintain 5.04 mAh cm^(-2)at a high sulfur loading(5.7 mg cm^(-2),5.0μL mg^(-1)),achieving 95.1%capacity retention after 80 cycles.This strategy of modifying local atomic environments offers a new route to designing highly active and stable catalysts. 展开更多
关键词 VACANCY Heteroatomic anchoring Vacancy migration activity/stability trade-off ELECTROCATALYSTS
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Strategies for balancing catalytic activity and stability in lithium-sulfur batteries
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作者 PENG Lin-kai SHI Ji-wei +3 位作者 CAO Yun LAN Jia-qi GENG Chuan-nan LV Wei 《新型炭材料(中英文)》 北大核心 2025年第4期889-908,共20页
Lithium-sulfur(Li-S)batteries have great promise for next-generation energy storage devices due to the high theoretical specific capacity(1675 mAh g^(-1))of sulfur with chemical conversion for charge storage.However,t... Lithium-sulfur(Li-S)batteries have great promise for next-generation energy storage devices due to the high theoretical specific capacity(1675 mAh g^(-1))of sulfur with chemical conversion for charge storage.However,their practical use is hindered by the slow redox kinetics of sulfur and the“shuttle effect”arising from dissolved lithium polysulfides(LiPSs).In recent years,various carbon-based materials have served as sulfur hosts and catalysts for accelerating sulfur conversion redox kinetics and alleviating LiPS shuttling.However,they often suffer from irreversible passivation and structural changes that destroy their long-term performance.We consider the main problems limiting their stability,including excessive LiPS adsorption,passivation by insulating Li2S,and surface reconstruction,and clarify how these factors lead to capacity fade.We then outline effective strategies for achieving long-term sulfur catalysis,focusing on functional carbon,such as designing suitable carbon-supported catalyst interfaces,creating well-distributed active sites,adding cocatalysts to improve electron transfer,and using carbon-based protective layers to suppress unwanted side reactions.Using this information should enable the development of stable,high-activity catalysts capable of long-term operation under practical conditions in Li-S batteries. 展开更多
关键词 Lithium-sulfur batteries CATALYSIS Catalyst poisoning Catalytic activity Catalytic stability
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Multi-metal synergistic integration for electronic structure regulation in schreibersite-type Mo_(2)Fe_(0.8)Ru_(0.2)P electrocatalysts:Exceptional enhancement of activity and stability for alkaline hydrogen evolution reaction 被引量:1
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作者 Peng Zhang Shiyu Xu +10 位作者 Hao Li Chenglin Cui Shengyang Huang Zhengyang Li Hyun Jun Song Lirui Mao Chan-Hwa Chung Ho Seok Park Jin Yong Lee Ji Man Kim Pil J.Yoo 《Journal of Energy Chemistry》 2025年第9期665-674,I0018,共11页
Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a... Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts. 展开更多
关键词 Hydrogen evolution reaction Multi-metallic regulation Schreibersite ELECTROCATALYSTS stability
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Enhanced stability and catalytic activity of subnanometric platinum cluster by surface doping of zirconium in CeO_(2)
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作者 Zheng Zhao Ziteng Mao +11 位作者 Weixin Zhao Zihao Xu Dongming Chen Bowen Wang Yongqi Zhang Meisheng Cui Yongke Hou Wenzheng Xia Yuqing Ling Juanyu Yang Zongyu Feng Xiaowei Huang 《Journal of Rare Earths》 2025年第4期719-725,I0003,共8页
There has been a continuous effort to improve the thermal stability of subnanometric platinum(Pt)cluster(<2 nm) catalyst because Pt cluster on CeO_(2) support can be mobile and aggregated into nanoparticle on heati... There has been a continuous effort to improve the thermal stability of subnanometric platinum(Pt)cluster(<2 nm) catalyst because Pt cluster on CeO_(2) support can be mobile and aggregated into nanoparticle on heating at elevated temperatures,yet this great challenge remains.In this study,a strategy is reported to improve the thermal stability of subnanometric Pt cluster by hydrothermal deposition method.Based on this method,zirconium(Zr) was precisely doped on surface of Ce_(0.95)Zr_(0.05)O_(2) by accurately controlling Pt subnanometric cluster size.The surface doping of Zr is favorable for forming the Zr-O-Ce site and activating surface lattice oxygen atoms,which results in strong electronic interactions to stabilize the Pt subnanometric cluster.After high-temperature aging treatment at 1000℃/4 h,the single atom Pt supported on CeO_(2) is aggregated into larger sized(>3 nm) nanoparticle.In contrast,the single atom Pt supported on Ce_(0.95)Zr_(0.0)5O_(2) displays less agglomeration into subnanometric cluster with size of(1.4±0.3) nm.Moreover,the CO oxide catalytic performance of Ce_(0.95)Zr_(0.0)5O_(2)-Pt is 26% and 31%higher than that of CeO_(2)-Pt and commercial Al_(2)O_(3)-Pt catalysts,respectively.The experimental and density functional theory(DFT) calculations indicate that the Zr-O-Ce site and Pt subnanometric cluster interface have more defect sites and active oxygen species than CeO_(2)-Pt interface,which activate the Mars van Krevelen(MvK) mechanism,facilitating the catalytic performance. 展开更多
关键词 CeO_(2) stability Rare earths Zr surface doping Subnanometric Pt cluster Catalytic activity
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Remarkable Enhancement of the Activity and Hydrothermal Stability of a CeO_(2)-Based NH_(3)-SCR Catalyst by Sn Modification
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作者 Ying Zhu Jingjing Liu +5 位作者 Guangzhi He Shaohua Xie Wenpo Shan Zhihua Lian Fudong Liu Hong He 《Engineering》 2025年第5期141-150,共10页
Catalytic activity and hydrothermal stability are both crucial for the application of the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR)catalyst in diesel vehicles.In this study,a tin(Sn)-modified Ce-N... Catalytic activity and hydrothermal stability are both crucial for the application of the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR)catalyst in diesel vehicles.In this study,a tin(Sn)-modified Ce-Nb mixed-oxide catalyst was synthesized as an NH_(3)-SCR catalyst for NO_(x)emission control.After the intro-duction of Sn,both the NH_(3)-SCR activity and the hydrothermal stability of the catalyst were remarkably promoted.Even after hydrothermal aging at 1000℃,the developed Ce_(1)Sn_(2)Nb_(1)O_(x)catalyst achieved more than 90%NO_(x)conversion at 325-500℃.Various methods,including N2-physisorption,X-ray diffraction,in-situ high-temperature X-ray diffraction,high-resolution transmission electron microscopy,X-ray pho-toelectron spectroscopy,X-ray absorption fine-structure spectroscopy,temperature-programmed reduc-tion of hydrogen,temperature-programmed desorption of ammonia,and density functional theory calculations were used to investigate the promotional effects induced by the Sn species.The characteri-zation results showed that the addition of Sn not only promoted the formation of the Ce-Nb active phase but also improved its thermal stability,contributing to the excellent NH_(3)-SCR performance and hydrothermal stability.This study provides an excellent sintering-resistance catalyst for the application of diesel engine NO_(x)emission control. 展开更多
关键词 SnO_(2) CeO_(2)-based catalyst NH_(3)-SCR Hydrothermal stability NO_(x)emission control
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Effects of silica additive on the NH_3-SCR activity and thermal stability of a V_2O_5/WO_3-TiO_2 catalyst 被引量:17
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作者 刘雪松 吴晓东 +3 位作者 许腾飞 翁端 司知蠢 冉锐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1340-1346,共7页
V2O5/WO3‐TiO2 and V2O5/WO3‐TiO2‐SiO2 catalysts were prepared by a wetness impregnation method, and both the catalysts were hydrothermally aged at 750℃ in 10 vol%H2O/air for 24 h. The catalysts were evaluated for N... V2O5/WO3‐TiO2 and V2O5/WO3‐TiO2‐SiO2 catalysts were prepared by a wetness impregnation method, and both the catalysts were hydrothermally aged at 750℃ in 10 vol%H2O/air for 24 h. The catalysts were evaluated for NOx conversion using NH3 as the reductant. Hydrothermal ageing decreased the NOx conversion of V2O5/WO3‐TiO2 catalyst severely over the entire measured tem‐perature range. Interestingly, the NH3‐SCR activity of the silica‐modified catalyst at 220–480℃ is enhanced after ageing. The catalysts were characterized by X‐ray diffraction, nitrogen adsorption, X‐ray fluorescence, Raman spectroscopy, H2 temperature‐programmed reduction, and NH3 temper‐ature‐programmed desorption. The addition of silica inhibited the phase transition from anatase to rutile titania, growth of TiO2 crystallite size and shrinkage of catalyst surface area. Consequently, the vanadia species remained highly dispersed and the hydrothermal stability of the V2O5/WO3‐TiO2 catalyst was significantly improved. 展开更多
关键词 V2O5/WO3-TiO2 SILICA NH3-SCR Hydrothermal stability Polymeric vanadia DE-NOX
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Structure-activity Relationships of the Coloration and Stability of Anthocyanidins 被引量:1
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作者 翁晨 赵昶灵 王崇德 《Agricultural Science & Technology》 CAS 2014年第4期526-532,共7页
Taking the six common anthocyanidins in nature, i.e. cyanidin, delphinidin, malvidin, pelargonidin, peonidin and petunidin, as examples, this paper summarized the main achievements about the structure-activity relatio... Taking the six common anthocyanidins in nature, i.e. cyanidin, delphinidin, malvidin, pelargonidin, peonidin and petunidin, as examples, this paper summarized the main achievements about the structure-activity relationships of the coloration and stability of anthocyanidins. The coloration and stability of anthocyanidins are funda- mentally determined by the chemical and spatial structures of the anthocyanidins. The electron-deficient state, hydroxylation and methylation patterns, especially the ones on the B-ring, and coplanarity of the three rings of anthocyanidins are inde- pendently or synergetically, positively and/or negatively, influence the coloration and stability of the anthocyanidins. Thereinto, the in vivo colorations of anthocyanins are also related to the organ-selective and crystal- or anthocyanic vacuolar inclusion- related existence of the anthocyanidins. This review could provide a reference for the researches of the structure-optimizing and function-exploiting of anthocyanidins and also for the selection of the crops and cultivars containing specific anthocyani- din profiles. 展开更多
关键词 Structure-activity relationship ANTHOCYANIDINS COLORATION stability
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Dynamics of the perturbed Calogero-Moser system:well-posedness,stability and blow up
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作者 LIU Qianle WANG Zhong ZHU Weipeng 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第1期157-168,共12页
We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separatio... We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separation condition for the particles.For suitably prepared initial configurations,local solutions can be extended globally via energy conservation;conversely,negative energy conditions induce(in)finite-time blowup.The linear(in)stability of stationary solutions is analyzed,with their energy serving as a threshold.Numerical investigations employ a fourth-order Runge-Kutta scheme with adaptive step-size control.Simulations demonstrate that the trajectories either converge to steady states or exhibit blowup,depending on the power exponent α and initial conditions.Increasingαaccelerates the convergence rate and dampens oscillatory dynamics,promoting a transition from periodic behavior to static equilibrium. 展开更多
关键词 Calogero-Moser system WELL-POSEDNESS blow up stability
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Systematic evaluation of reference gene stability across tissues and sexes in cuttlefish(Sepiella japonica)
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作者 LI Shuang GU Min +5 位作者 YE Xiaowen YE Bin LIU Siyu YU Jia ZHOU Xu CHI Changfeng 《水产学报》 北大核心 2026年第2期26-49,共24页
Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa su... Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa such as cephalopods,systematic evaluation of reference genes is limited,leading to potential bias.The cuttlefish Sepiella japonica is ecologically and economically important in China,yet previous molecular studies have often relied on single unvalidated reference genes,which may compromise data reliability.This study aimed to systematically evaluate the stability of five commonly used reference genes(18S,ef-1α,ef-1γ,gapdh,andβ-actin)across multiple tissues and sexes of S.japonica,and to identify the most suitable reference genes and optimal number for qPCR normalization.Fifteen to sixteen tissue types were collected from ten healthy adults(five males and five females).Total RNA was extracted,reverse-transcribed,and analyzed by qPCR.Gene stability was assessed using four algorithms(geNorm,NormFinder,BestKeeper,andΔCt)integrated with RefFinder,and the optimal gene number was determined using geNorm pairwise variation(V_(n/n+1)<0.15).Four transcriptome-derived genes(creld2,cd109,acy1,and miox)were used for validation.The C_(t)values of the five genes ranged from 15.47 to 20.83.β-actin and gapdh showed pronounced variability in expression stability among tissues and sexes,indicating their limited suitability for normalization.18S exhibited the highest expression(mean C_(t):15.47-16.29)and lowest variability but displayed sex-biased expression,whereas ef-1αand ef-1γremained consistently stable across most tissues in both sexes,with ef-1αbeing the most robust and showing no sex-related bias.Although specific rankings varied among tissues and sexes,the comprehensive results indicated that ef-1αand ef-1γpossessed the highest overall stability,followed by 18S,whileβ-actin and gapdh were the least stable.The final comprehensive rankings were ef-1γ>ef-1α>18S>gapdh>β-actin(male)and ef-1α>ef-1γ>18S>gapdh>β-actin(female).geNorm analysis(V2/3<0.15)indicated that two genes,mainly ef-1αand ef-1γ,were generally sufficient for reliable normalization in most tissues.Validation confirmed that normalization using the stable ef-1αand ef-1γaccurately reflected the expression differences among tissues,whereasβ-actin and gapdh can bias or confound statistical analyses.ef-1αand ef-1γare identified as the most reliable reference gene combination for qPCR analysis in S.japonica,while 18S can serve as an auxiliary gene for within-sex comparisons.The use ofβ-actin or gapdh alone is not recommended.This study establishes a systematic framework for selecting reliable reference genes in S.japonica,thereby facilitating robust qPCR normalization and providing a foundation for future gene expression research in S.japonica and other cephalopods. 展开更多
关键词 Sepiella japonica reference genes qPCR expression stability RefFinder
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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Silver chloride/chitosan‑based chloramine nanohybrid with excellent antibacterial activity:Design and structure characterization as well as Ag^(+)‑Cl^(-)synergistic antibacterial effect
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作者 ZHANG Xinzhe XU Jiarong +4 位作者 GAO Mochou LIU Yage ZHAO Yanbao CUI Jingzeng ZOU Xueyan 《无机化学学报》 北大核心 2026年第2期428-438,共11页
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle... Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests. 展开更多
关键词 AgCl@SiO_(2)/CTS‑Cl hybrid nanoparticle synergistic effect antibacterial activity
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Preoperative butyrylcholinesterase activity and risk of postoperative delirium:A meta-analysis
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作者 Yuan-Li Qiu Cheng Song +1 位作者 Cui-Wan Huang Wei-Gang Shen 《World Journal of Psychiatry》 2026年第1期385-399,共15页
BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate... BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate the association between preoperative serum cholinesterase(ChE)activity—specifically butyrylcholinesterase(BuChE)and acetylcholinesterase(AChE)—and the risk of POD in adult surgical patients in a meta-analysis.METHODS A systematic search was conducted in PubMed,EMBASE,and Web of Science up to March 28,2025 for studies reporting preoperative serum BuChE or AChE activity in relation to subsequent POD incidence.Standardized mean differences(SMDs)and odds ratios(ORs)with 95%confidence intervals(CIs)were pooled using random-effects models.Subgroup and sensitivity analyses were performed based on follow-up duration and analytic models.RESULTS Thirteen studies(n=2730 patients)were included.Patients who developed POD had significantly lower preoperative BuChE activity than those who did not(SMD=-0.28;95%CI:-0.39 to-0.16;I^(2)=18%).Higher BuChE activity was associated with a reduced risk of POD(OR per 100 unit increment=0.97;95%CI:0.95-0.99;I2=0%).In contrast,pooled AChE activity did not differ significantly between POD and non-POD groups(SMD=-0.25;95%CI:-0.53 to 0.03;P=0.08;I^(2)=80%),and the ORs per 1 unit increment in AChE activity were not statistically significant(OR=0.98;95%CI:0.95-1.01).CONCLUSION Lower preoperative serum BuChE activity is associated with an increased risk of POD in adults undergoing surgery.BuChE activity may serve as a potential preoperative biomarker for POD risk stratification. 展开更多
关键词 ACETYLCHOLINESTERASE BUTYRYLCHOLINESTERASE activity Postoperative delirium META-ANALYSIS
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Time-dependent ground stability of inclined backfilled stope characterized by creep behavior
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作者 Ruofan Wang Yujie Zhu +3 位作者 Lang Liu Mengbo Zhu Baoxu Yan Hao Cui 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期479-491,共13页
Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional... Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional assumption that the fill material exhibits a significantly lower stiffness than the host rocks.Significantly,a recent pioneering work revealed the time-dependent ground stability around a backfilled stope with vertical walls through numerical modeling.In practice,underground stopes typically exhibit a higher or lower degree of inclination.This alters the stress state in peripheral rocks and may induce severe instability and dilution,particularly in stope-hanging walls.Hence,it is imperative to analyze the time-dependent ground stability of inclined backfilled stopes for backfill structure design.Therefore,comprehensive numerical simulations were performed using FLAC3D to address this knowledge deficiency by incorporating a coupled analysis of the backfill consolidation behavior and long-term creep deformation in surrounding rocks.The ground stability was evaluated based on the confinement effectiveness,strength-stress ratio,stress path relative to the yield surface,and time-dependent stress redistribution in the rocks.A parametric study revealed that the inclination angle of the backfilled stope reduced the confinement effectiveness in the host rocks when the wall creep was minor.This exacerbated the rock mass sloughing potential.However,a backfilled stope with a shallower dip angle achieved superior ground stability enhancement when the creep deformation was substantial,by applying a more significant compression on the backfill and effectively mobilizing its passive support performance during consolidation.Additional simulations were conducted to analyze the effects of stope height and width,mine depth,mechanical properties of rocks,backfill compressibility,and filling gap on the time-dependent stress redistribution and stability around the inclined backfilled stope. 展开更多
关键词 inclined backfilled stope ground stability time-dependency creep CONSOLIDATION
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Study on the Extraction of Flavonoids from Hylocereus undatus(Haw.)Britton&Rose and Their Antioxidant Activity
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作者 Zhao LIU Deyun MA +1 位作者 Rimeng CHEN Meijiao MO 《Agricultural Biotechnology》 2026年第1期65-69,共5页
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r... [Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products. 展开更多
关键词 Hylocereus undatus FLAVONOIDS Antioxidant activity
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Positive/negative binocular fusional C-optotypes and 2D planar C-optotypes on transient accommodation and stability in adult eyes:implications for myopia prevention and control
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作者 Qing-Xia Fan Jing Lin +1 位作者 Ling Xu Wei He 《International Journal of Ophthalmology(English edition)》 2026年第3期539-548,共10页
AIM:To investigate the effects of binocular fusional C-optotypes(positive/negative)and 2D planar C-optotypes on the amplitude and stability of transient accommodation(TAC)in adults,and to provide a basis for non-conta... AIM:To investigate the effects of binocular fusional C-optotypes(positive/negative)and 2D planar C-optotypes on the amplitude and stability of transient accommodation(TAC)in adults,and to provide a basis for non-contact myopia intervention.METHODS:This was a self-controlled study.Using redblue 3D technology,four experimental stages were set up:Test A[fixating on the 1 m negative fusional C-optotypes,8△base-in(BI)],Test B(fixating on the 5 m planar C-optotypes),Test C(fixating on the 1 m planar C-optotypes),and Test D[fixating on the 1 m positive fusional C-optotypes,20△base-out(BO)].A WAM-5500 open-field autorefractor was used to measure TAC and accommodative microfluctuations[evaluated via interquartile range(IQR)and median-based coefficient of variation(CVmed)].Additionally,the convergence accommodation to convergence(CA/C)ratio was calculated,and a visual fatigue questionnaire was administered to assess participants’subjective visual comfort.RESULTS:A total of 21 subjects(7 males,14 females;aged 23-41y)with normal binocular visual function were enrolled.The results showed that the TAC increased gradually across the four stages,and these values were Test A(-0.35±0.26 D)<Test B(-0.46±0.24 D)<Test C(-0.77±0.32 D)<Test D(-1.38±0.31 D).There were significant overall differences(F=56.136,P<0.001).Compared with Test C,Test A reduced TAC by 0.42 D(P<0.05),while Test D increased it by 0.61 D(P<0.001).There was no significant intergroup difference in accommodative fluctuation amplitude(all P>0.05),but the fluctuation stability of Test D showed a significant difference between the first 20s and the second 20s(P=0.017).The CA/C ratio was significantly higher in Test D(0.05±0.02 D/△)than in Test A(0.03±0.02 D/△,P=0.007),indicating stronger accommodation-convergence linkage during positive fusional fixation.The visual fatigue scores of all stages were low(median 0-1),with Test D slightly higher than Test B and Test C(P<0.05).No linear correlation was found between TAC and age(all r<0.1,P>0.05).CONCLUSION:Negative fusional C-optotypes induce ciliary muscle relaxation to reduce TAC,while positive fusional C-optotypes enhance accommodation-convergence coordination to increase TAC.The red-blue 3D-based noncontact training mode exhibits good safety(median visual fatigue scores:0-1 across all tests)and provides a novel dual-directional(relaxation-activation)strategy for myopia prevention and control. 展开更多
关键词 fusional accommodation transient accommodation accommodative stability myopia control
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Innovative Strategies to Overcome Stability Challenges of Single‑Atom Nanozymes
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作者 Rong Guo Qiuzheng Du +3 位作者 Yaping He Haoan Wu Yu Zhang Ziwei Jing 《Nano-Micro Letters》 2026年第3期725-756,共32页
Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomed... Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomedical field.However,stability issues may impede the clinical translation of SAzymes.This review provides a comprehensive overview of the applications of SAzymes in various biomedical fields,including disease diagnosis(e.g.,biosensors and diagnostic imaging),antitumor therapy(e.g.,photothermal therapy,photodynamic therapy,sonodynamic therapy,and immunotherapy),antimicrobial therapy,and anti-oxidative stress therapy.More importantly,the existing challenges of SAzymes are discussed,such as metal atom clustering and active site loss,ligand bond breakage at high temperature,insufficient environment tolerance,biosecurity risks,and limited catalytic long-term stability.Finally,several innovative strategies to address these stability concerns are proposed—synthesis process optimization(space-limited strategy,coordination site design,bimetallic synergistic strategy,defect engineering strategy,atom stripping-capture),surface modification,and dynamic responsive design—that collectively pave the way for robust,clinically viable SAzymes. 展开更多
关键词 Single-atom nanozymes Clinical translation stability issues Innovative strategies BIOCOMPATIBILITY
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Global Stability of Traveling Wavefronts for a Belousov-Zhabotinsky Model with Mixed Nonlocal and Degenerate Diffusions
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作者 Yuting YANG Guobao ZHANG 《Journal of Mathematical Research with Applications》 2026年第1期87-102,共16页
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal... In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique. 展开更多
关键词 Belousov-Zhabotinsky model nonlocal diffusion stability comparison principle weighted energy
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Stability analysis of soft-hard interbedded anti-inclined rock slope under rainfall based on deformation compatibility
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作者 GUO Jianjun WU Zhenwei +2 位作者 CAO Heng ZHANG Wei WANG Junjie 《Journal of Mountain Science》 2026年第1期380-393,共14页
Rock slope instability is a prevalent geological hazard that imposes significant adverse impacts on engineering activities.Although existing studies have focused on homogeneous rock slopes,the theoretical models for q... Rock slope instability is a prevalent geological hazard that imposes significant adverse impacts on engineering activities.Although existing studies have focused on homogeneous rock slopes,the theoretical models for quantifying the stability of softhard interbedded anti-inclined slopes remain underdeveloped,primarily due to the complex force transfer mechanisms involved.This study proposed a novel theoretical model for the stability analysis of soft-hard interbedded anti-inclined slopes under rainfall conditions.The framework models stratified rock layers as layered cantilever beams with material heterogeneity.Based on the principle of deformation compatibility,it comprehensively accounted for interlayer force transfer and strength degradation resulting from differential deformations among rock layers.Furthermore,it integrated the critical instability length induced by the self-weight of rock layers to determine the fracture depth.The proposed method was validated against engineering case studies and physical model tests,with error falling within an acceptable range.Compared to existing theoretical methods,the proposed method provided a more realistic representation of the slope's stress field.The analysis results demonstrate that rainfall not only reduces the inclination angle of the failure surface but also leads to an approximate 30%decrease in the safety factor.The proposed theoretical model is particularly useful for quickly calculating the stability of soft-hard interbedded anti-inclined rock slope under rainfall conditions,compared to complex and time-consuming numerical simulation calculations. 展开更多
关键词 Soft-hard interbedded Anti-inclined slope RAINFALL stability analysis Theoretical method
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Physical activity and exercise within the context of obesity treatment:Enhancing health beyond weight loss
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作者 John M.Jakicic Christian E.Behrens +7 位作者 Sarah E.Deemer Bethany Forseth Christos S.Katsanos Brett S.Nickerson Wagner L.Prado Xuewen Wang Landon S.Deru Renee J.Rogers 《Journal of Sport and Health Science》 2026年第2期31-40,共10页
Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss... Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss to reduce the associated health burden.Physical activity is an important lifestyle behavior associated with enhanced health.Evidence supports that many of the benefits of physical activity are realized independent of initial weight status or whether weight loss is achieved,with some benefits additive to what is achieved with weight loss alone.These benefits include enhanced cardiometabolic,brain,cognitive and psychological health,and others.Moreover,in adults with overweight or obesity,physical activity has independent effects on cardiorespiratory fitness,muscular strength,physical function,and mobility.There are also benefits to body composition,with physical activity improving the quality of key tissues,such as skeletal muscle,which may not occur with diet-induced weight loss.Therefore,physical activity is an important public health target for adults with overweight or obesity to provide a wide range of health benefits that extend beyond those of weight loss alone.However,physical activity recommendations and programming efforts should consider the unique characteristics of adults with overweight or obesity to be most effective,and should support a focus on mobility,physical function,and other health outcomes. 展开更多
关键词 Physical activity EXERCISE OBESITY Body composition Health risk
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Sustainable fungicide delivery via imazalil-functionalized nano-coordination polymer carriers:Enhanced stability,environmental safety,and pH-responsive properties
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作者 Gao-Sheng Zhu Zhen-Hang Xu +6 位作者 Shao-Zhan Lan Long Li Yan-Ying Zheng Lu Zhang Qiao-Xia Shang Bao-Yi Yu Chong-Chen Wang 《Chinese Chemical Letters》 2026年第2期728-734,共7页
The preparation of a novel nanoscale imazalil(IMZ)-based coordination polymer[Zn(HBTC)(IMZ)_(2)]_(n)(PDCP1)(H_(3)BTC=1,3,5-benzenetricarboxylic acid),and its antifungal application within a sustainable delivery system... The preparation of a novel nanoscale imazalil(IMZ)-based coordination polymer[Zn(HBTC)(IMZ)_(2)]_(n)(PDCP1)(H_(3)BTC=1,3,5-benzenetricarboxylic acid),and its antifungal application within a sustainable delivery system was reported.The intermolecular interactions presented in the structure,and their contributions to crystal packing were studied by Hirshfeld,Fingerprint plot and Mayer bond order.The obtained PDCP1 had a relativelyhigh loadingrate of IMZ(68.5%).PDCP1 exhibitednotable antifungal activities againstColletotrichum gloeosporioides,Magnaporthe Oryzae,and Alternaria Nees strains,with EC_(50) values of 0.72,0.92,and 0.56μg/mL,respectively.The key benefits of the application of PDCP1 as a control release pesticide include high fungicide loading and offer nearly complete release,pH-responsive release,enhanced UV stability,exhibits favorable biosafety profiles.The remarkable inhibition of C.gloeosporioides growth by PDCP1 underscores a promising strategy for agrochemical material development,high loading of active ingredients and readily delivery fosters more efficient pesticides utilization in agricultural processes. 展开更多
关键词 Nano-fungicide Fungicide release Antifungal activity CP fungicide IMAZALIL
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