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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Study on Active Components from the Stems of Polyalthia plagioneura(II)
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作者 Bingjing LIU Guikun TANG 《Agricultural Biotechnology》 2026年第1期63-64,69,共3页
[Objectives]This study was conducted to isolate and identify the components from stems of Polyalthia plagioneura.[Methods]The compounds were isolated and purified by silica gel column,Sephadex LH-20,and C_(18) chromat... [Objectives]This study was conducted to isolate and identify the components from stems of Polyalthia plagioneura.[Methods]The compounds were isolated and purified by silica gel column,Sephadex LH-20,and C_(18) chromatography.Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.[Results]Five compounds were isolated and identified as:di(2-ethylhexyl)phthalate(1),cinnamic anhydride(2),phthalic acid(3),citric acid(4),and syringaldehyde(5).[Conclusions]All compounds were isolated from this plant for the first time. 展开更多
关键词 Polyalthia plagioneura Chemical component STEROID
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Microstructure and properties of HPDC AM60 based alloys for super-sized integrated automotive components
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作者 Jing WANG Xin GUO +8 位作者 Jiang-feng SONG Dang-he SHI He-cong XIE Chun-yu LI Heng-rui HU Gong CHEN Bin JIANG Dong-xia XIANG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第2期433-450,共18页
The commercial AM60(Mg−6Al−0.3Mn)die-casting alloy was modified through Mn,Ce,and La micro-alloying,each at a content below 0.2 wt.%.SEM,TEM,and Micro-CT were employed to characterize the microstructures and propertie... The commercial AM60(Mg−6Al−0.3Mn)die-casting alloy was modified through Mn,Ce,and La micro-alloying,each at a content below 0.2 wt.%.SEM,TEM,and Micro-CT were employed to characterize the microstructures and properties of AM60 based alloys.AM60-0.2La alloy showed excellent mechanical properties.The ultimate tensile strength,yield strength,and elongation of(288.0±1.7)MPa,(158.0±1.0)MPa,and(22.0±3.0)%were achieved in AM60-0.2La alloy.Besides,AM60-0.2La alloy exhibited the best corrosion resistance(0.29 mm/a)and fluidity among the investigated four alloys.The excellent mechanical properties and corrosion resistance are mainly attributed to the grain refinement strengthening,low porosity,and low content of large shrinkage porosity,promising for super-sized integrated automotive components. 展开更多
关键词 magnesium alloys microstructure mechanical properties high-pressure die-casting integrated automotive components
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Comprehensive quality evaluation and principal component analysis of Crassostrea gigas from North Yellow Sea,China:characterizing nutritional,flavor,and functional profiles
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作者 Shanqin HUO Jixing PENG +3 位作者 Xinnan ZHAO Yichen LIN Xudong LI Zhijun TAN 《Journal of Oceanology and Limnology》 2026年第1期406-418,共13页
Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characte... Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry. 展开更多
关键词 Crassostrea gigas nutritional quality principal component analysis comprehensive evaluation
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Criticality,resilience and prioritization of components in interdependent infrastructure systems:An overview of definitions and quantitative modelling approaches
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作者 Georgios Alexandros Chatzistefanou Albert S.Chen +2 位作者 Slobodan Djordjevic Lydia S.Vamvakeridou-Lyroudia Dragan A.Savic 《Resilient Cities and Structures》 2026年第1期118-132,共15页
Enhancing the resilience of critical infrastructure(CI)systems has become a focal point of national and inter-national policies.However,the formulation of resilience enhancement strategies often requires component-(i.... Enhancing the resilience of critical infrastructure(CI)systems has become a focal point of national and inter-national policies.However,the formulation of resilience enhancement strategies often requires component-(i.e.asset-)level prioritization,which entails many complexities.Acknowledging the complex and interdependent nature of infrastructure systems,this paper aims to aid researchers,practitioners and policy-makers by pre-senting a review of the relative literature and current state-of-the-art,and by identifying future research op-portunities to improve the applicability and operationalizability of CI component identification and prioritization methods.Theoretical and practical applications are reviewed for definitions,analysis and modelling approaches regarding the resilience of interdependent infrastructure systems.A detailed review of infrastructure criticality definitions,component criticality assessment and prioritization frameworks,from scientific,policy and other documents,is presented.A discussion on social justice and equity dimensions therein is included,which have the potential to greatly influence decisions and should always be incorporated in infrastructure planning and in-vestment discussions.The findings of this review are discussed in terms of applicability and operationalizability.Key recommendations for future research include:(i)developing quantification frameworks for CI component criticality based on formal definitions and multiple criteria,(ii)incorporating the entire resilience cycle of CI in component prioritization,(iii)accounting for the socio-technical nature of CI systems by integrating social di-mensions and their wider operating environment and(iv)developing comprehensive model validation,cali-bration and uncertainty analysis frameworks. 展开更多
关键词 Critical infrastructure Interdependencies CRITICALITY RESILIENCE component importance measures Cascading effects System-of-systems
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Multi-pass intermittent local loading process of large-scale rib-web component:Forming characteristics and implementing apparatus
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作者 Dawei ZHANG Peng DONG +2 位作者 Jingxiang LI Zijian YU Shengdun ZHAO 《Chinese Journal of Aeronautics》 2026年第1期601-625,共25页
The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and redu... The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and reduce forming loads.However,the absence of compatible forming equipment makes it difficult to control the constraint in the unloaded zones during the forming process.This difficulty complicates coordination and control of deformation,particularly for asymmetric rib-web components.Additionally,the current implementation involves multi-fire heating,a long process flow,and high energy consumption,which limits the popularization and application of the local loading process.In this study,a new multi-pass local loading hydraulic forming apparatus that can quickly and reliably switch between heavy-load deformation and low-load constraint for different local loading sub-dies was developed.A 10-tonne laboratory prototype was developed,and the forming characteristics during the forming process as well as the response characteristics of the hydraulic system during the multi-pass intermittent local loading of rib-web component were investigated using numerical simulations and physical experiments.Results indicated that,compared to a whole loading process with the same initial geometry of billet,the total forming load(i.e.,the sum of loaded and restrained loads)is reduced by more than 40%with the local loading process,and by nearly 50%with multi-pass local loading.The multi-pass local loading process allows for more effective control of material flow compared to single-pass local loading,leading to improved cavity filling and reduced flow line disturbance.For a large-scale,complex titanium alloy bulkhead,the cavity filling problem was addressed by optimizing the multi-pass local loading path with an unequal thickness billet.The dynamic performance of the multi-pass local loading hydraulic system was found to be robust,with stable pressure transitions during motion and load switching for the sub-die(s).The dynamic characteristic of the hydraulic cylinder when switching from non-moving/unloaded state to a moving/loading state are consistent whether a load is present or not.However,the dynamic characteristics differ when switching from a moving/loading state to non-moving/unloaded state,showing opposite behavior.The developed hydraulic drive mechanism provides a way for implementation of multi-pass local loading without auxiliary operation and extra heating.The results of the study provide a foundation for the industrial production of large-scale,complex components with reduced force requirement and low-energy consumption. 展开更多
关键词 Forming characteristics Hydraulic system Intermittent local loading process Material flow Rib-web component
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Advances in Component Separation Methods of Lignocellulosic Biomass
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作者 Lida Wang Qiang Zhi +1 位作者 Guoshun Liu Wenzhi Li 《Chinese Journal of Chemical Physics》 2026年第1期89-117,I0043,共30页
Lignocellulosic biomass is the most abundant re-newable resource on Earth,boasting advan-tages such as wide avail-ability and negative car-bon emissions.Especial-ly,efficient separation of lignocellulose into cellu-lo... Lignocellulosic biomass is the most abundant re-newable resource on Earth,boasting advan-tages such as wide avail-ability and negative car-bon emissions.Especial-ly,efficient separation of lignocellulose into cellu-lose,hemicellulose and lignin,and realizing val-orization of these compo-nents are more responsive to the development needs of biomass refinery and the green chem-istry era.This review outlines the main components of lignocellulose and briefly summerizes their utilization in chemical raw materials and energy production.It mainly focused on cur-rent advances in component separation methods of lignocellulose by organic solvents,ionic liquids and deep eutectic solvents.The design of separation methods,understanding of sepa-ration mechanisms,and optimization of reaction systems in each method are highlighted in detail.Furthermore,the ongoing challenges and future directions based on mechanism and in-dustrialization are critically discussed.Our goal is to elucidate the separation mechanisms and principles of method design,providing guidance for the development of highly efficient com-ponent separation methods of lignocellulose. 展开更多
关键词 Lignocellulosic biomass component separation Organic solvent Ionic liquid Deep eutectic solvent
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Two-Stage LightGBM Framework for Cost-Sensitive Prediction of Impending Failures of Component X in Scania Trucks
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作者 Si-Woo Kim Yong Soo Kim 《Computers, Materials & Continua》 2026年第3期1222-1240,共19页
Predictive maintenance(PdM)is vital for ensuring the reliability,safety,and cost efficiency of heavyduty vehicle fleets.However,real-world sensor data are often highly imbalanced,noisy,and temporally irregular,posing ... Predictive maintenance(PdM)is vital for ensuring the reliability,safety,and cost efficiency of heavyduty vehicle fleets.However,real-world sensor data are often highly imbalanced,noisy,and temporally irregular,posing significant challenges to model robustness and deployment.Using multivariate time-series data from Scania trucks,this study proposes a novel PdM framework that integrates efficient feature summarization with cost-sensitive hierarchical classification.First,the proposed last_k_summary method transforms recent operational records into compact statistical and trend-based descriptors while preserving missingness,allowing LightGBM to leverage its inherent split rules without ad-hoc imputation.Then,a two-stage LightGBM framework is developed for fault detection and severity classification:Stage A performs safety-prioritized fault screening(normal vs.fault)with a false-negativeweighted objective,and Stage B refines the detected faults into four severity levels through a cascaded hierarchy of binary classifiers.Under the official cost matrix of the IDA Industrial Challenge,the framework achieves total misclassification costs of 36,113(validation)and 36,314(test),outperforming XGBoost and Bi-LSTM by 3.8%-13.5%while maintaining high recall for the safety-critical class(0.83 validation,0.77 test).These results demonstrate that the proposed approach not only improves predictive accuracy but also provides a practical and deployable PdM solution that reduces maintenance cost,enhances fleet safety,and supports data-driven decision-making in industrial environments. 展开更多
关键词 Predictive maintenance two-stage classification cost-based evaluation LightGBM scania component X dataset
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Advanced forming technologies for integrated metal components with extreme size and structure:State-of-the-art and perspectives
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作者 Yizhe Chen Shilong Zhao +7 位作者 Yicheng Wang Yanxiong Liu Zhili Hu Dongsheng Qian Xinghui Han Hui Wang Jianguo Lin Lin Hua 《Chinese Journal of Mechanical Engineering》 2026年第1期211-235,共25页
In aerospace,nuclear power,and new energy vehicles industries,utilizing integrated metal components with extreme sizes and/or structures is crucial for achieving significant weight-saving,performance-improvement,and e... In aerospace,nuclear power,and new energy vehicles industries,utilizing integrated metal components with extreme sizes and/or structures is crucial for achieving significant weight-saving,performance-improvement,and excellent reliability.These components,made from metal sheets,rings,or tubes,exhibit characteristics like ultra-thin,ultra-thick,ultra-large,ultra-long,ultra-high ribs,and large variable diameters.During plastic de-formation in metal forming processes,defects such as ruptures,wrinkles,excessive strain differences,and un-expected weak performance areas are likely to occur due to the intersection of multiple effects in different research disciplines,including materials science,processes,and mechanics of materials.Consequently,the smooth forming of integrated parts is difficult.It is the first time to review,summarize,and analyze the ad-vancement of forming methods for producing integrated parts with extreme sizes and structures.The general academic ideas to change the process conditions and sequences to optimize stress state and improve plastic deformation ability for forming the components with extreme sizes/structures are introduced.Practical ex-amples,discussed in detail in the paper,include the forming of(i)integrated ultra-thin and ultra-thick sheet components;(ii)integrated ultra-large size ring components with thin wall and high ribs;and(iii)integrated ultra-long tube components with large perimeter difference.Various plasticity technologies and process se-quences have been developed.The key processes and applications of the technologies are discussed in detail,which achieve successful plastic forming of integrated components.This paper provides state-of-the-art and perspectives for the rapidly advancing material forming fields of key metal components for the next generation of equipment. 展开更多
关键词 Advanced forming technologies Integrated metal components Extreme size and structure
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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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Surface-immobilized cross-linking tetraalkylammonium cations networks mitigate hydrogen evolution for pure acidic CO_(2)reduction in proton-exchange membrane electrolyzers
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作者 Min Zhang Zengyi Tan +3 位作者 Mufan Xing Yang Wang Xun Zhu Qian Fu 《Journal of Energy Chemistry》 2026年第1期90-96,I0004,共8页
The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative... The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis. 展开更多
关键词 Pure acidic CO_(2)electroreduction Mitigate hydrogen evolution Polyelectrolyte cations MEA electrolyzer
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Overexpression of mitofusin 2 ameliorates inflammation and oxidative stress in lipopolysaccharide-induced mastitis model by regulating phosphofurin acidic cluster sorting protein 2
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作者 Xiechen Zhou Yufei Zhang +5 位作者 He Ma Shoupeng Fu Juxiong Liu Wenjin Guo Xiaofeng Tian Bingxu Huang 《Animal Models and Experimental Medicine》 2026年第1期154-167,共14页
Background:Mastitis seriously affects the mammary health of humans and animals.Studies have found that inflammation and oxidative stress play key roles in the occur-rence and development of mastitis.Therefore,in-depth... Background:Mastitis seriously affects the mammary health of humans and animals.Studies have found that inflammation and oxidative stress play key roles in the occur-rence and development of mastitis.Therefore,in-depth research on related molecular mechanisms is of great significance.Methods:Postpartum mice were anesthetized with pentobarbital and administered lipopolysaccharide to develop the mouse mastitis model.Proteomic analysis was per-formed to compare protein expression in mitochondria-associated endoplasmic retic-ulum membranes(MAM)from two mouse mammary gland groups.Western blot was used to detect the expression of MAM-related proteins in mitochondria.AlphaFold3 was used to predict the molecular structures of phosphofurin acidic cluster sorting protein 2(PACS2)and mitofusin 2(MFN2)and their interaction levels.The MFN2-PACS2 interaction was investigated using co-immunoprecipitation and small interfer-ing RNA.Results:The results showed that the inflammation level in the mammary gland tissue of mice with mastitis significantly increased,the total antioxidant capacity decreased,and the expression of MAM-related proteins MFN2 and PACS2 was significantly downregulated.In cell experiments,overexpression of MFN2 can inhibit inflamma-tion and oxidative stress responses,and promote the interaction between MFN2 and PACS2 to affect the formation of MAMs.Conclusion:In summary,this study suggests that mastitis can alter the expression of MAM-related proteins in mouse breast tissue.The interaction between MFN2 and PACS2 regulates the formation of MAMs.Overexpression of MFN2 can promote the formation of MAMs and inhibit inflammation and oxidative stress response in mam-mary epithelial cells.Our results provided a new theoretical basis and potential thera-peutic targets for the prevention and treatment of mastitis. 展开更多
关键词 MASTITIS mitochondria-associated endoplasmic reticulum membranes(MAM) mitofusin 2(MFN2) phosphofurin acidic cluster sorting protein 2(PACS2)
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Bronsted acidic ionic liquid [C_3SO_3HDoim]HSO_4 catalyzed one-pot three-component Biginelli-type reaction: An efficient and solvent-free synthesis of pyrimidinone derivatives and its mechanistic study 被引量:3
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作者 Zhi-Lei Zhou Peng-Cheng Wang Ming Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第2期226-230,共5页
A series of Bronsted acidic ionic liquids(ILs) were prepared and used for Biginelli-type condensation reaction among aromatic aldehydes, urea or thiourea and cyclopentanone. Through this reaction, the synthesis of v... A series of Bronsted acidic ionic liquids(ILs) were prepared and used for Biginelli-type condensation reaction among aromatic aldehydes, urea or thiourea and cyclopentanone. Through this reaction, the synthesis of various pyrimidinones could be achieved. Of interest, it was found that the reaction was efficiently catalyzed by a novel, eco-friendly functionalized IL [C3SO3HDoim]HSO4, which could be reused for at least 7 times without significantly loss of catalytic activity. The reaction proceeded efficiently at 80℃ to afford the desired products in good yield(up to 96%). In addition, a possible mechanism that accounted for the IL [C3SO3HDoim]HSO4-catalyzed reaction was proposed. 展开更多
关键词 Bronsted acidic ionic liquids Catalysis Biginelli-type reaction PYRIMIDINONE Organic synthesis Applied chemistry
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Leaching potential and changes in components of metals in two acidic ferrisols 被引量:16
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作者 郭朝晖 廖柏寒 黄昌勇 《Journal of Central South University of Technology》 EI 2006年第6期631-636,共6页
Two acidic ferrisols, i.e., red soil (RS) and yellow red soil (YRS), from the vicinity regions of non-ferrous ores in Hunan province of China, were leached with simulated acid rain through artificial column experi... Two acidic ferrisols, i.e., red soil (RS) and yellow red soil (YRS), from the vicinity regions of non-ferrous ores in Hunan province of China, were leached with simulated acid rain through artificial column experiments. The results show that the total leaching mass of metals are m(Zn)〉m(Cu)〉m(Cd) from the original soils and m(Cd)〉m(Zn)〉〉 m(Cu) from the contaminated soils with external metals after leaching for 60 d continuously, leaching quantities of Cd and Zn from the contaminated red soil (CRS) are more than that from the contaminated yellow red soil (CYRS), but for Cu, it is almost the same. The preferential fractions for leaching are mainly in exchangeable forms, and content of exchangeable forms decreases significantly in the contaminated soil profiles. The unstable fractions of Cd, Cu and Zn in the RS and YRS increase significantly with the decrease of pH value of simulated acid rain. Changes of fi, actions of external Cd, Cu, and Zn in the residual CRS and CYRS profiles are significantly affected by the acidity of acid rain, too. After leaching for 60 d continuously, Cd exists mostly in exchangeable form, Cu exists mainly in exchangeable, manganese oxide-occluded and organically bounding forms, and Zn exists in residual in CRS and CYRS profiles. Most of exchangeable Cd and Zn exist only small in surface layer (0-20 cm) and are transferred to the sub-layers, contrarily, Cu accumulates mostly in the topsoil (0-20 cm) with low translocation. 展开更多
关键词 acidic ferrisols leaching behavior metals contamination column experiment
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Bond engineering:weakening Ru-O covalency for efficient and stable water oxidation in acidic solutions 被引量:3
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作者 Yifan Yang Jingtong Guo +4 位作者 Lixiong Xu Chenyue Li Rongqian Ning Jun Ma Shuo Geng 《Journal of Energy Chemistry》 2025年第3期1-9,共9页
The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has ... The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has been recognized as a viable strategy to foster the stability of RuO_(2)for acidic OER applications.This study presented an ion that does not readily gain or lose electrons,Ba^(2+),into RuO_(2)(Ba-RuO_(2))nanosheet(NS)catalyst that increased the number of exposed active sites,achieving a current density of 10 mA/cm^(2)with an overpotential of only 229 mV and sustaining this output for over 250 h.According to density functional theory(DFT)and X-ray absorption spectroscopy,Ba doping resulted in a longer Ru-O bond length,which in turn diminished the covalency of the bond.This alteration curtailed the involvement of LO and the dissolution of ruthenium(Ru),thereby markedly improving the durability of the catalyst over extended periods.Additionally,attenuated total reflectance-surface enhanced infrared absorption spectroscopy analysis substantiated that the OER mechanism shifted from a LO-mediated pathway to an adsorbate evolution pathway due to Ba doping,thereby circumventing Ru over-oxidation and further enhancing the stability of RuO_(2).Furthermore,DFT findings uncovered that Ba doping optimizes the adsorption energy of intermediates,thus enhancing the OER activity in acidic environments.This study offers a potent strategy to guide future developments on Ru-based oxide catalysts'stability in an acidic environment. 展开更多
关键词 Oxygen evolution reaction in acid Bond covalency Rutheniumoxide Ba doping
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Therapeutic components of acupuncture stimulation based on characteristics of sensory nerve and nervous signaling pathway 被引量:1
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作者 Hyo-Sun Wie Seung-Nam Kim 《Journal of Integrative Medicine》 2025年第2期106-112,共7页
Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.Thi... Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.This review systematically explores the therapeutic components of acupuncture,emphasizing the interplay between sensory nerve characteristics and neural signaling pathways.Key factors such as acupoint location,needling depth,stimulation intensity,retention time,and the induction of sensations(e.g.,Deqi)are analyzed for their roles in neural activation and clinical outcomes.The review highlights how variations in spinal segment targeting,tissue-specific receptor activation,and stimulation modalities(e.g.,manual acupuncture,electroacupuncture,moxibustion)influence therapeutic effects.Emerging evidence underscores the significance of ion channels,dermatomes,myotomes,and genespecific pathways in mediating systemic effects.Additionally,the differential roles of mechanical,thermal and nociceptive stimuli and the temporal dynamics of sensory and immune responses are addressed.While insights from animal models have advanced our understanding,their translation to clinical practice requires further investigation.This comprehensive review identifies critical parameters for optimizing acupuncture therapy,advocating for individualized treatment strategies informed by neuroanatomical and neurophysiological principles,ultimately enhancing its precision and efficacy in modern medicine. 展开更多
关键词 Sensory nerve ACUPUNCTURE Nervous system Therapeutic component Acupuncture point MERIDIANS
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Insight into the sorption and desorption pattern of pyrrolizidine alkaloids and their N-oxides in acidic tea(Camellia sinensis)plantation soils 被引量:2
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作者 Yuting Lu Haolei Han +5 位作者 Yuexing Yi Yunfeng Chai ChenWang Xiangchun Zhang Xiangde Yang Hongping Chen 《Journal of Environmental Sciences》 2025年第2期350-363,共14页
Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci... Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology. 展开更多
关键词 Pyrrolizidine alkaloids Sorption-desorption behavior Tea plantation system acidic soil Linear regression model
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Selective flotation of ilmenite from titanaugite under weakly acidic pH conditions using 2-amino-1-propanol as novel depressant 被引量:1
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作者 Chuan DAI Pan CHEN +2 位作者 Yao-hui YANG Wei SUN Hong-bin WANG 《Transactions of Nonferrous Metals Society of China》 2025年第4期1325-1337,共13页
The potential of 2-amino-1-propanol(AP)as a novel depressant in selectively floating ilmenite from titanaugite under weakly acidic conditions was investigated.Micro-flotation results show that AP significantly reduces... The potential of 2-amino-1-propanol(AP)as a novel depressant in selectively floating ilmenite from titanaugite under weakly acidic conditions was investigated.Micro-flotation results show that AP significantly reduces the recovery of titanaugite while having no evident impact on ilmenite flotation.Subsequent bench-scale flotation tests further confirm a remarkable improvement in separation efficiency upon the introduction of AP.Contact angle and adsorption tests reveal a stronger affinity of AP towards the titanaugite surface in comparison to ilmenite.Zeta potential measurements and X-ray photoelectron spectroscopy(XPS)analyses exhibit favorable adsorption characteristics of AP on titanaugite,resulting from a synergy of electrostatic attraction and chemical interaction.In contrast,electrostatic repulsion hinders any significant interaction between AP and the ilmenite surface.These findings highlight the potential of AP as a highly efficient depressant for ilmenite flotation,paving the way for reduced reliance on sulfuric acid in the industry. 展开更多
关键词 ILMENITE titanaugite selective flotation weakly acidic condition depressant
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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing High dynamic MEMS components Multiscale control Process optimization High dynamic verification
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Sulfur poisoned PtNi/C catalysts toward two-electron oxygen reduction reaction for acidic electrosynthesis of hydrogen peroxide 被引量:1
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作者 Xin Yang Lijie Zhong +7 位作者 Songxin Ye Dequan He Shuxian Yuan Huixin Li Yuting Ma Xiaocheng Mo Shiyu Gan Li Niu 《Journal of Materials Science & Technology》 2025年第1期268-275,共8页
Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for ... Selective electrocatalysis of two-electron oxygen reduction reaction(2e^(-)ORR)has been recognized as a sustainable and on-site process for hydrogen peroxide(H_(2)O_(2))production.Great progress has been achieved for 2e^(-)ORR in alkaline media.However,it is challenged by insufficient activity and selectiv-ity of the catalysts in acidic electrolytes.Herein,we report sulfur-poisoned PtNi/C catalysts(PtNiSx/C)that could regulate ORR from the 4e^(-)to 2e^(-)pathway.The identified PtNiS0.6/C offers high activity in terms of onset potential of∼0.69 V(vs.RHE)and∼80%selectivity.The mass activity is also compara-ble and outperforms representative Pt-based precious and transition-metal-based catalysts.In addition,it is interestingly found that the Faradaic efficiency further increased to 95%during the long-term elec-trolysis test due to Ni atom surface migration.The electrochemical production of the H_(2)O_(2)system was applied to the electro-Fenton process,which has realized the effective degradation of organic pollutants.This work offers a strategy by sulfur poisoning PtNi/C catalyst to realize Pt-based 2e^(-)ORR active catalysts to electrolysis of H_(2)O_(2)in acidic media. 展开更多
关键词 Oxygen reduction reaction Hydrogen peroxide acidic media ELECTROCATALYSIS
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