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Syntheses,crystal structures,catalytic and anti-wear properties of zinc(Ⅱ),nickel(Ⅱ)and cadmium(Ⅱ)complexes constructed from a terphenyl-tricarboxylate ligand
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作者 ZHAO Zhenghua LIU Yufeng +2 位作者 ZHANG Qing SHI Zifa GU Jinzhong 《无机化学学报》 北大核心 2026年第1期170-180,共11页
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc... Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3. 展开更多
关键词 COMPLEXES tricarboxylic acid catalytic properties Knoevenagel condensation reaction anti-wear performance
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Antibacterial agrochemicals:Recent research progress and outlook
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作者 Shaobo Wang Honggui Yang +2 位作者 Chunni Zhao Deyu Hu Baoan Song 《Chinese Chemical Letters》 2026年第1期10-24,共15页
Plant bacterial diseases cause significant harm to agricultural production because of their frequent,intermittent and regional outbreaks.Currently,chemical control is still a more effective method for bacterial diseas... Plant bacterial diseases cause significant harm to agricultural production because of their frequent,intermittent and regional outbreaks.Currently,chemical control is still a more effective method for bacterial disease.To develop new,efficient and safe antibacterial agrochemicals,we summarize the research progress of compounds with antibacterial activities in the past ten years,classify them according to their active skeletons,and discuss their structure-activity relationships and mechanisms of action.Finally,the development trend of antibacterial agrochemicals was prospected.This review provides valuable information for the development of antibacterial agrochemicals. 展开更多
关键词 Agrochemicals BACTERICIDES ANTIBACTERIAL Active skeleton Structure-activity relationships Mechanism of action
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In situ analysis and mechanistic understanding of gas species generated in battery cells during thermal abuse
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作者 Vamakshi Yadav Michelle H.Wiebenga +5 位作者 Daad Haddad James R.Salvador Nicholas P.W.Pieczonka Robert D.Schmidt Hernando J.Gonzalez Malabet Lei Wang 《Journal of Energy Chemistry》 2026年第3期699-708,共10页
Understanding gas generation in lithium-ion batteries during thermal runaway is critical to designing safer electric vehicles.We developed an in situ gas analysis system capable of measuring gases as they are generate... Understanding gas generation in lithium-ion batteries during thermal runaway is critical to designing safer electric vehicles.We developed an in situ gas analysis system capable of measuring gases as they are generated inside a lab-scale battery cell during thermal abuse.Two phases of gas-generating reactions were observed in charged Lithium Nickel Cobalt Manganese Aluminum Oxide(NCMA)-graphite cells.By adding a lithium iron phosphate(LFP)-based reference electrode inside the cell,we find that reactions occurring between the anode and electrolyte generate H_(2) and CO_(2) in the 80–130℃ temperature range.These reactions are correlated with the self-heating onset observed in accelerated rate calorimetry(ARC)and involve both solid electrolyte interphase(SEI)and intercalated lithium.Above 160℃,reactions occurring due to cathode decomposition accelerate thermal runaway and generate large amounts of carbon dioxide,and to a lesser extent,hydrogen and ethylene.The methods presented herein can be used to evaluate cell thermal stability for the design of safer batteries. 展开更多
关键词 Thermal runaway Lithium-ion battery In situ gas analysis Three-electrode gas cell
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Comparative Study of Clinical Efficacy of Two Skin Health Programs under Massage Intervention
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作者 Zhao Xuehua Liu Jianwei +2 位作者 Zi Yusha Hu Weiren Peng Xianwu 《China Detergent & Cosmetics》 2026年第1期18-26,共9页
Instrumental and expert assessments were used to assess the effect of massage on facial skin blood perfusion,as well as the effects of the long-term use of the two skin health programs on the water content of the stra... Instrumental and expert assessments were used to assess the effect of massage on facial skin blood perfusion,as well as the effects of the long-term use of the two skin health programs on the water content of the stratum corneum,F4,L^(*),dermal and epidermal thickness and density,facial wrinkles,and so on.Sixty healthy Chinese women were selected as the study subjects,which were subsequently divided into G1 non-massage group and G2 massage group.The results show that massage can increase the blood perfusion of facial skin.Group G2 solution is found to be more effective in improving the skin structural barrier(epidermal density),skin elasticity,firmness(dermal thickness)and forehead wrinkles. 展开更多
关键词 skin health program facial massage skin blood perfusion skin thickness skin density ANTI-WRINKLE
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Development of silicon carbide fiber-reinforced silicon oxycarbide composites for low-observable unmanned aerial vehicle exhaust nozzles via filament winding,and polymer infiltration and pyrolysis
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作者 Byeong-Joo Kim Ji Eun Lee +4 位作者 Chang-Bin Oh Doo Hyun Choi Man Young Lee Dae Young Jo Shin Kim 《Defence Technology(防务技术)》 2026年第2期49-65,共17页
Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance b... Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance. 展开更多
关键词 Filament winding Polymer infiltration and pyrolysis Ceramic matrix composites Exhaust nozzle Low observability
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HDFPM:A Heterogeneous Disk Failure Prediction Method Based on Time Series Features
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作者 Zhongrui Jing Hongzhang Yang Jiangpu Guo 《Computers, Materials & Continua》 2026年第2期2187-2211,共25页
Hard disk drives(HDDs)serve as the primary storage devices in modern data centers.Once a failure occurs,it often leads to severe data loss,significantly degrading the reliability of storage systems.Numerous studies ha... Hard disk drives(HDDs)serve as the primary storage devices in modern data centers.Once a failure occurs,it often leads to severe data loss,significantly degrading the reliability of storage systems.Numerous studies have proposed machine learning-based HDD failure prediction models.However,the Self-Monitoring,Analysis,and Reporting Technology(SMART)attributes differ across HDD manufacturers.We define hard drives of the same brand and model as homogeneous HDD groups,and those from different brands or models as heterogeneous HDD groups.In practical engineering scenarios,a data center is often composed of a heterogeneous population of HDDs,spanning multiple vendors and models.Existing research predominantly focuses on homogeneous datasets,ignoring the model’s generalization capability across heterogeneous HDDs.As a result,HDD models with limited samples often suffer from poor training effectiveness and prediction performance.To address this issue,we investigate generalizable SMART predictors across heterogeneous HDD groups.By extracting time-series features within a fixed sliding time window,we propose a Heterogeneous Disk Failure Prediction Method based on Time Series Features(HDFPM)framework.This method is adaptable to HDD models with limited sample sizes,thereby enhancing its applicability and robustness across diverse drive populations.Experimental results show that the proposed model achieves an F1-score of 0.9518 when applied to two different Seagate HDD models,while maintaining the False Positive Rate(FPR)below 1%.After incorporating the Complexity-Ratio Dynamic Time Warping(CDTW)based feature enhancement method,the best prediction model achieves a True Positive Rate(TPR)of up to 0.93 between the two models.For next-day failure prediction across various Seagate models,the model achieves an F1-score of up to 0.8792.Moreover,the experimental results also show that within the same brand,the higher the proportion of shared SMART attributes across different models,the better the prediction performance.In addition,HDFPMdemonstrates the best stability andmost significant performance in heterogeneous environments. 展开更多
关键词 Heterogeneous hard disk drives failure prediction time series feature constrained dynamic time warping sensitivity analysis
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Manipulating and unveiling contributions of the reactive oxygen species dramatically promote selective photo-oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid in aqueous solution
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作者 Runqing Xiao Qingmao Yang +3 位作者 Yanjie Li Wei Zhang Gang Xiao Chun Shen 《Green Energy & Environment》 2026年第2期488-499,共12页
Achieving high selectivity to 2,5-furandicarboxylic acid(FDCA)in the photocatalytic oxidation of 5-hydroxymethylfurfural(HMF)in aqueous solution advocates the principle of green and sustainable chemistry,but still rem... Achieving high selectivity to 2,5-furandicarboxylic acid(FDCA)in the photocatalytic oxidation of 5-hydroxymethylfurfural(HMF)in aqueous solution advocates the principle of green and sustainable chemistry,but still remains a significant challenge.Herein,manipulating the reactive oxygen species(ROS)has been realized and dramatically promotes the selective photocatalytic oxidation of HMF in aqueous solution.A high FDCAyield of 98.6% has been achieved after 3 h of visible light irradiation over the as-prepared FeO_(x)-Au/TiO_(2) catalyst,being one of the leading photocatalytic performances.Furthermore,satisfactory FDCA yields of higher than 80%could be realized even in the outdoor environment under natural sunlight irradiation,regardless of sunny or cloudy weather.A combination study including physical characterization,kinetic analysis,radical trapping experiments and density functional theory calculations unveils the rate-determining step(oxidation of hydroxyl group)and respective contributions of the generated ROS(1O_(2) and·O_(2)-)in each step of the entire reaction network.The present work would push ahead the understanding of HMF photocatalytic oxidation and contribute to the rational design of high-performance photocatalysts. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL 2 5-Furandicarboxylic acid Reactive oxygen species Singlet oxygen Photocatalytic oxidation
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Ultra-high-temperature resistant water-based drilling fluid technology for ten-kilometer ultra-deep wells
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作者 LIU Fengbao YIN Da +3 位作者 LUO Xuwu SUN Jinsheng HUANG Xianbin WANG Ren 《Petroleum Exploration and Development》 2026年第1期221-234,共14页
Two types of ultra-high-temperature resistant water-based drilling fluid additives were designed and developed:an ultra-high-temperature resistant salt-tolerant polymer fluid loss reducer,and an ultra-high-temperature... Two types of ultra-high-temperature resistant water-based drilling fluid additives were designed and developed:an ultra-high-temperature resistant salt-tolerant polymer fluid loss reducer,and an ultra-high-temperature resistant micro-nano plugging agent.An ultra-high-temperature resistant water-based drilling fluid system meeting the requirements of ultra-deep well drilling was established.Laboratory test and field application were employed for performance evaluation.The ultra-high-temperature and high-salt resistant polymer fluid loss reducer exhibits a mesh-like membrane structure with numerous cross-linking points,and its high-temperature and high-pressure(HTHP)loss was 28.2 m L after aging at 220℃under saturated salt conditions.The ultra-high-temperature resistant micro-nano plugging agent adaptively filled mud cake pores/fractures through deformation,thus reducing the fluid loss.At elevated temperatures,it transitioned to a viscoelastic state to effectively cement the rock on wellbore wall and enhanced wall stability.The ultra-high-temperature resistant water-based drilling fluid system with a density of 1.6 g/cm^(3)exhibits excellent rheological properties at high temperature and high pressure.Its HTHP fluid loss at 220℃was only 9.6 m L.It maintains a stable performance under high-temperature and high-salt conditions,with a sedimentation factor below 0.52 after holding at high temperature for 7 d,and generates no H_(2)S gas after aging,demonstrating good lubricity and safety.This drilling fluid system has been successfully applied in the 10000-meter ultra-deep well of China,Shenditake 1,in Tarim Oilfield,ensuring the well's successful drilling to a depth of 10910 m. 展开更多
关键词 ultra-high-temperature resistant water-based drilling fluid fluid loss reducer plugging agent ten-kilometer ultra-deep well Shenditake 1 well
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A reservoir rock wettability modifier for ultra-high temperature and high salinity environment
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作者 Ling Lin Yulong Bai +2 位作者 Yue Feng Yuanzhi Qu Taigang Zhou 《Energy Geoscience》 2026年第1期81-89,共9页
During drilling process,the water phase in drilling fluids infiltrates rock fractures through capillary action.The surface wettability of dolomite is governed by multiple factors,resulting in an unstable wetting state... During drilling process,the water phase in drilling fluids infiltrates rock fractures through capillary action.The surface wettability of dolomite is governed by multiple factors,resulting in an unstable wetting state.Studies have shown that altering the surface wettability of reservoir rocks to an intermediate wetting state can effectively reduce the damage of drilling fluids to oil and gas reservoirs and improve oil and gas recovery.Therefore,it is necessary to develop a reservoir protectant to prevent the water phase in the drilling fluid from intruding into the oil and gas reservoirs.Given this,a modified polysiloxane was synthesized to alter the surface wettability of dolomite.Tetramethylcyclotetrasiloxane(D^(H)_(4))and octamethylcyclotetrasiloxane(D_(4))were ring-opened copolymerized to obtain the hydrogencontaining polysiloxane,which in turn reacted with unsaturated hydrocarbons to obtain the modified polysiloxane.The ability of reservoir protectants to regulate the surface wettability of dolomite under high-temperature and high-salinity conditions was tested.The experimental results show that the reservoir protectant is able to alter the wettability of the dolomite surface to an intermediate wetting state by adsorption on the rock surface even after 16 h of aging at 240℃ and 15% salt concentration. 展开更多
关键词 Rreservoir protectant POLYSILOXANE WETTABILITY Heat resistance Salt tolerance
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Development of AI-Based Monitoring System for Stratified Quality Assessment of 3D Printed Parts
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作者 Yewon Choi Song Hyeon Ju +1 位作者 Jungsoo Nam Min Ku Kim 《Computer Modeling in Engineering & Sciences》 2026年第1期661-679,共19页
The composite material layering process has attracted considerable attention due to its production advantages,including high scalability and compatibility with a wide range of raw materials.However,changes in process ... The composite material layering process has attracted considerable attention due to its production advantages,including high scalability and compatibility with a wide range of raw materials.However,changes in process conditions can lead to degradation in layer quality and non-uniformity,highlighting the need for real-time monitoring to improve overall quality and efficiency.In this study,an AI-based monitoring system was developed to evaluate layer width and assess quality in real time.Three deep learning models Faster Region-based Convolutional Neural Network(R-CNN),You Only Look Once version 8(YOLOv8),and Single Shot MultiBox Detector(SSD)were compared,and YOLOv8 was ultimately selected for its superior speed,flexibility,and scalability.The selected model was integrated into a user-friendly interface.To verify the reliability of the system,bead width control experiments were conducted,which identified feed speed and extrusion speed as the key process parameters.Accordingly,a Central Composite Design(CCD)experimental plan with 13 conditions was applied to evaluate layer width and validate the system’s reliability.Finally,the proposed system was applied to the additive manufacturing of an aerospace component,where it successfully detected bead width deviations during printing and enabled stable fabrication with a maximum geometric deviation of approximately 6 mm.These findings demonstrate the critical role of real-time monitoring of layer width and quality in improving process stability and final product quality in composite material additive manufacturing. 展开更多
关键词 Large-scale material extrusion additive manufacturing vision-based process monitoring aerospace composite tooling real-time quality control deep learning
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Influence of Nb addition on microstructure evolution and superplastic behavior of Ti-5Al-5Mo-5Cr-2Zr-xNb titanium alloy at 923 K
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作者 Shi-chen Sun Hong-ze Fang +3 位作者 Jia-qi Hao Bao-hui Zhu Xian-fei Ding Rui-run Chen 《China Foundry》 2026年第1期55-61,共7页
Ti-5Al-5Mo-5Cr-2Zr-xNb with different Nb(abbreviated as Ti-5552-xNb,x=3,6,9,12,wt.%)contents were stretched at 923 K to study their superplastic behavior and mechanical properties below recrystallization temperature.T... Ti-5Al-5Mo-5Cr-2Zr-xNb with different Nb(abbreviated as Ti-5552-xNb,x=3,6,9,12,wt.%)contents were stretched at 923 K to study their superplastic behavior and mechanical properties below recrystallization temperature.The microstructure of as-cast Ti-5552-xNb alloy is consisted of a singleβphase,and theβgrain size increases slightly with the increase of Nb content.The thermal effect in the process of high temperature drawing leads to the precipitation ofαphase.The addition of Nb in Ti-5552 titanium alloys reduces theα/βphase transformation temperature,which causes a decrease in the volume fraction ofαphase.Reducing theαphase content reduces incompatibility,but too low a proportion ofαphase will lead to premature fracture,so tensile strength and plasticity firstly increase and then decrease.The results show that Ti-5552-9Nb titanium alloy shows the best tensile strength(307.2 MPa)and superplasticity(106%).The superplastic mechanism of Ti-5552-9Nb alloy is mainly caused by relative sliding ofβgrain boundaries and dislocation movement. 展开更多
关键词 titanium alloy niobium element SUPERPLASTIC mechanical properties
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Impact of sidewall passivation on reliability in InGaN-based micro-LEDs
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作者 Tae Kyoung Kim Abu Bashar Mohammad Hamidul Islam +8 位作者 Jongil Kim Hyeondong Lee Minji Kim Joohan Bae June-O Song Dong-Soo Shin Jong-In Shim Sang Ho Oh Joon Seop Kwak 《Advanced Photonics Nexus》 2026年第1期186-201,共16页
The performance degradation of micro light-emitting diodes(micro-LEDs)is closely associated with the deterioration of sidewall passivation layers under prolonged electrical bias.We investigate reliability improvements... The performance degradation of micro light-emitting diodes(micro-LEDs)is closely associated with the deterioration of sidewall passivation layers under prolonged electrical bias.We investigate reliability improvements in 20μm×20μm InGaN/GaN blue micro-LEDs by suppressing the formation of an unstable interfacial layer during sidewall passivation.SiO_(2)is deposited on the etched mesa sidewalls using either Sputtering or plasma-enhanced chemical vapor deposition(PECVD).Comparative analysis reveals that PECVD-passivated devices experience more severe performance degradation,primarily due to the increased leakage current.After 100 h of accelerated aging,external quantum efficiency decreases by 44%in PECVD-passivated samples,whereas Sputter-passivated devices exhibit only an11%reduction.This discrepancy is attributed to the formation of a thicker and chemically unstable gallium oxynitride(Ga-O_(X)-N_(1-X))interfacial layer at the SiO_(2)∕GaN-based interface,which facilitates the generation of sidewall defects.Suppressing the formation of this interlayer enhances the crystallinity and structural stability of the passivation layer,thereby mitigating the activation of point defects.Notably,Sputter deposition is more effective in minimizing the formation of Ga-O-N interlayer.These findings emphasize the critical role of achieving low-defect-density sidewall passivation to improve the reliability of micro-LEDs for next-generation high-resolution display applications. 展开更多
关键词 micro light-emitting diode SPUTTER plasma-enhanced chemical vapor deposition PASSIVATION external quantum efficiency point defect RELIABILITY interfacial layer
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An overview of the advantageous effects and underlying mechanisms of natural polysaccharides in inflammatory bowel disease
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作者 Yating Shao Bo Li +6 位作者 Yongfang Wang Chuanjie Zhou Yunlong Qiao Xinglishang He Shengqiang Tong Guiyuan Lv Suhong Chen 《Chinese Journal of Natural Medicines》 2026年第1期45-58,共14页
Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continu... Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continue to increase.While multiple clinical treatments exist,conventional therapies frequently present limitations and adverse effects.Natural polysaccharides(PSs)have emerged as a significant focus of research interest due to their therapeutic potential and applications in functional foods and health products.This review synthesizes current understanding of IBD pathophysiology and the mechanisms by which natural PSs counter IBD,including their capacity to restore immune homeostasis and intestinal barrier function,modulate gut microbiota and metabolites,reduce oxidative stress,and address irregularities in autophagy and endoplasmic reticulum stress(ERS).The review examines the structure-activity relationships of PSs demonstrating anti-IBD effects and identifies promising therapeutic products.The discussion encompasses pharmacokinetics,safety evaluations,and clinical applications of these compounds.This comprehensive review establishes a theoretical foundation for developing natural PS-based therapeutic approaches for IBD management. 展开更多
关键词 Natural polysaccharides Inflammatory bowel disease PATHOGENESIS Therapeutic effect Research progress
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Synthesis and insecticidal activity evaluation of sulfonamide derivatives oriented by atom replacement strategy
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作者 Hao Qian Xinru Tan +8 位作者 Guixun Wu Lei Wang Ziyu Wang Hongxiang Liu Mei Tian Minjie Zhang Keyin Yu Wenjun Wu Jiwen Zhang 《Advanced Agrochem》 2026年第1期49-57,共9页
The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify t... The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify the sulfonamide scaffold identified in our previous work,and resulting in the synthesis of 40 novel sulfonamide derivatives not previously reported in the literature.The insecticidal activities of these compounds against the Mythimna separata and Plutella xylostella were assessed.Our findings indicate that the pyridine sulfonamide structure significantly enhances insecticidal efficacy.Specifically,compound 7c exhibited LC 50 values of 0.157 and 0.256 mg/mL against the M.separata and P.xylostella,which significantly increased 97-and 41-fold compared to celangulin V,respectively.The experimental results revealed that pyridine sulfonamide analogues could serve as potential green insecticides. 展开更多
关键词 SULFONAMIDE SYNTHESIS Insecticidal activity Atom replacement Celangulin V
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TGF-β/BMP signaling in skeletal biology:molecular mechanisms,regulatory networks,and therapeutic implications in development,regeneration,and disease
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作者 Junguang Liao Taofen Wu +9 位作者 Qi Zhang Panpan Shen Ziyi Huang Jiaqi Wang Pengxiang Zhang Sisi Lin Jiashun Pi Nenghua Zhang Haidong Wang Guiqian Chen 《Bone Research》 2026年第1期109-140,共32页
The transforming growth factor-β(TGF-β)and bone morphogenetic protein(BMP)signaling pathways are pivotal regulators of cellular processes,playing indispensable roles in embryogenesis,postnatal development,and tissue... The transforming growth factor-β(TGF-β)and bone morphogenetic protein(BMP)signaling pathways are pivotal regulators of cellular processes,playing indispensable roles in embryogenesis,postnatal development,and tissue homeostasis.These pathways are particularly critical within the skeletal system,as they coordinate osteogenesis,chondrogenesis,and bone remodeling through intricate molecular mechanisms.TGF-β/BMP signaling is primarily transduced via canonical Smad-dependent pathways(e.g.,ligands,receptors,and intracellular Smads)and the non-canonical Smad-independent(e.g.,p38 mitogen-activated protein kinase,MAPK)cascade.Both pathways converge on master transcriptional regulators,including Runx2 and Osterix,and their precise coordination is indispensable for skeletal development,maintenance,and repair.The dysregulation of TGF-β/BMP signaling contributes to a spectrum of skeletal dysplasia and bone pathologies.Advances in molecular genetics,particularly gene-targeting strategies and transgenic mouse models,have deepened our understanding of the spatiotemporal control of TGF-β/BMP signaling in bone and cartilage development.Moreover,emerging research underscores extensive crosstalk between TGF-β/BMP and other critical pathways,such as Wnt/β-catenin,mitogen-activated protein kinase(MAPK),parathyroid hormone(PTH)/PTH-related protein(PTHrP),fibroblast growth factors(FGF),Hedgehog,Notch,insulin-like growth factors(IGF)/insulin-like growth factors receptor(IGFR),Mammalian target of rapamycin(mTOR),and autophagy,forming an integrated regulatory network that ensures skeletal integrity.Our review synthesizes the current knowledge on the molecular components,regulatory mechanisms,and functional integration of TGF-β/BMP signaling in skeletal biology,with an emphasis on its roles in development,regeneration,and disease.By elucidating the molecular underpinnings of TGF-β/BMP pathways and their contextual interactions,we aim to highlight translational opportunities and novel therapeutic strategies for treating skeletal disorders. 展开更多
关键词 transforming growth factor molecular mechanismstgf bmp tissue homeostasisthese bone remodeling skeletal systemas skeletal biology molecular mechanisms bone morphogenetic
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Effect of Ta addition on microstructure and mechanical properties of Ti46Al1.5Cr8Nb alloy
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作者 Jiang-shan Liang Liao Mi +4 位作者 Hong-ze Fang Xin Ding Xian-fei Ding Bao-hui Zhu Rui-run Chen 《China Foundry》 2026年第1期37-44,共8页
The microstructure of high Nb-TiAl alloys was optimized by the addition of a small amount of Ta elements to further improve their properties.A series of Ti46Al1.5Cr8Nb-xTa(x=0.2,0.4,0.6,0.8,1.0,at.%)alloys were prepar... The microstructure of high Nb-TiAl alloys was optimized by the addition of a small amount of Ta elements to further improve their properties.A series of Ti46Al1.5Cr8Nb-xTa(x=0.2,0.4,0.6,0.8,1.0,at.%)alloys were prepared by vacuum arc melting.The microstructure,mechanical properties,and related influencing mechanisms were systematically investigated.The results indicate that the solidification microstructure of the Ti46Al1.5Cr8Nb-xTa alloys comprises theγ-TiAl phase,α_(2)-Ti_(3)Al phase,and B2 phase.As the Ta content increases from 0.2 at.%to 1.0 at.%,the content ofα_(2)phase and B2 phase increases,while theγphase content decreases.Among them,the B2 phase shows the most pronounced change,being significantly refined,with its content increasing from 12.49%to 21.91%.In addition,the average size of the lamellar colony decreases from 160.65 to 94.44μm.The addition of the Ta element shifts the solidification path toward lower aluminum concentrations,leading to changes in phase content.The tantalum-induced increase in the B2 phase and enhanced supercooling at the solidification front provide the basis for lamellar colony refinement.Compressive testing at room temperature reveals that the Ti46 Al1.5 Cr8 Nb0.4 Ta alloy exhibits optimal compressive properties,achieving a compressive strength of 2,434 MPa and a compressive strain of 33.1%.The improvement of its properties is attributed to a combination of lamellar colony refinement,solid solution strengthening resulting from the incorporation of Ta element,and a reduction in the c/a of theγphase. 展开更多
关键词 TiAl alloy Ta element microstructure mechanical properties lamellar colony
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Process analysis of nuclear hydrogen production via intermediate temperature SOEC electrolysis
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作者 Qing Shao Yue Lu +7 位作者 Dun Jin Ling-Hong Luo Xiu-Lin Wang Hui-Chao Yao Ruo-Yun Dai Cheng-Zhi Guan Guo-Ping Xiao Jian-Qiang Wang 《Nuclear Science and Techniques》 2026年第2期122-133,共12页
When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.Howe... When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges. 展开更多
关键词 Nuclear hydrogen production SOEC STABILITY Intermediate temperature
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Marine fungal metabolite butyrolactone Ⅰ improves Aβ_(1-42)-induced cognitive impairment in mice via gut-brain axial microbiota remodeling,anti-inflammation,and antioxidation
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作者 Fuyan YANG Longjian ZHOU +5 位作者 Jiahang DENG Yuan WANG Zhiyou YANG Yongping ZHANG Yayue LIU Yi ZHANG 《Journal of Oceanology and Limnology》 2026年第1期386-405,共20页
Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-infla... Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis. 展开更多
关键词 Alzheimer’s disease butyrolactoneⅠ cognitive deficit microbiota composition oxidative stress NEUROINFLAMMATION
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Fuel-Powered Soft Actuators:Emerging Strategies for Autonomous and Miniaturized Robots
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作者 Cheng Zhou Zhoutao Li +9 位作者 Hailong Wei Guorong Zhang Fengrui Zhang Xiaoshuang Zhou Hongwei Hu Guanggui Cheng Jianning Ding Shi Hyeong Kim Ray H.Baughman Xinghao Hu 《Nano-Micro Letters》 2026年第4期598-620,共23页
Soft actuators,capable of producing mechanical work in response to external stimuli,have potential applications in robotics and exoskeletons.However,they face major challenges related to energy supply,especially in lo... Soft actuators,capable of producing mechanical work in response to external stimuli,have potential applications in robotics and exoskeletons.However,they face major challenges related to energy supply,especially in long-distance and miniaturized environments.Fuel-driven actuators offer a promising solution by enabling the conversion of chemical energy into mechanical energy,supporting selfsustaining operations.Chemical energy from fuel can be converted into mechanical energy either directly or indirectly through methods such as electron transfer-induced charge injection,structural changes,fuel-to-electricity conversion,fuel combustioninduced heat,or fuel-induced pneumatic actuation.This paper provides a comprehensive review of recent developments in fuel-powered actuators,covering their fundamental principles,advancements,and challenges.It concludes with an outlook for miniaturized and autonomous robots,highlighting the great potential of integrating fuel-powered actuators. 展开更多
关键词 Fuel-powered soft actuators Fuel electrochemical actuators Fuel thermal actuators Fuel-pneumatic actuators
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Enhanced visible light response and cytocompatibility of TiO_(2)-TiC shell-core structured S-scheme photocatalyst
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作者 Yuanyuan Li Sujun Guan +6 位作者 Yingda Qian Liang Hao Sheikh Mohamed Mohamed Lijun Wang Takaomi Itoi Yun Lu Xinwei Zhao 《International Journal of Minerals,Metallurgy and Materials》 2026年第3期999-1011,共13页
To enhance the visible light response of titanium dioxide(TiO_(2)),titanium carbide(TiC)nanoparticles(NPs)were thermally treated in carbon powder,effectively overcoming the challenges associated with conventional dopi... To enhance the visible light response of titanium dioxide(TiO_(2)),titanium carbide(TiC)nanoparticles(NPs)were thermally treated in carbon powder,effectively overcoming the challenges associated with conventional doping methods.During the treatment,a TiO_(2)thin shell with oxygen vacancies(OVs)formed around the TiC NPs,creating a shell-core structure S-scheme photocatalyst.Transmission electron microscopy(TEM)and ultraviolet-visible(UV-vis)spectroscopy confirmed the successful formation of the TiO_(2)shell.By optimizing the shell thickness,the TiO_(2)-TiC shell-core structure achieved an ideal shell-core ratio,resulting in strong visible light absorption(400-800 nm),and the degradation rate constant of Rhodamine B(RhB)of sample cHT500 reached 0.0687 min^(−1),which is 20.8times higher than that of pristine TiO_(2)(0.0033 min^(−1))under visible-light irradiation.In addition,cytocompatibility tests showed that sample cHT500 exhibits favorable cell viability,which is comparable to that of TiO_(2)nanoparticles,and thus remarkably mitigates the poor biocompatibility inherent to TiC,making them promising candidates for biomedical and photocatalytic applications. 展开更多
关键词 S-scheme heterojunction PHOTOCATALYSIS titanium dioxide shell-core structure CYTOCOMPATIBILITY
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