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Analysis of Active Components of Hexane Extractives of Morus alba Leaves 被引量:2
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作者 刘志明 王海英 张爽 《Agricultural Science & Technology》 CAS 2011年第1期23-25,共3页
[Objective]The aim was to explore the active compound of Morus alba leaves with the analysis of active components of hexane extractives of M.alba leaves.[Method]Antibacterial assays of hexane extractives of M.alba lea... [Objective]The aim was to explore the active compound of Morus alba leaves with the analysis of active components of hexane extractives of M.alba leaves.[Method]Antibacterial assays of hexane extractives of M.alba leaves were done and the volatile components of hexane extractives of M.alba leaves with the strongest antibacterial activity were analyzed by gas chromatography-mass spectrometry(GC-MS).[Result]The results of inhibitory effect of hexane extractives of M.alba leaves on Staphylococcus aureus and Escherichia coli showed that hexane extractives of M.alba leaves collected in June,July and August had antibacterial activity against S.aureus and had no antibacterial effect against E.coli.Furthermore,hexane extractives of M.alba leaves collected in June had the strongest antibacterial activity against S.aureus(inhibition diameter 10.95 mm).The hexane extractives of M.alba leaves collected in June was analyzed by GC-MS,the main volatile components were tetradecane(16.76%),dodecane(13.20%),diisobutyl phthalate(10.26%),decane(9.10%),hexadecane(8.71%),linolenyl alcohol(7.25%),octadecane(5.88%),eicosane(3.26%),dibutyl phthalate(2.59%).[Conclusion]Linolenyl alcohol was the potential antibacterial compound. 展开更多
关键词 Morus alba Hexane extractives Active components Linolenyl alcohol Gas chromatography-mass spectrometry
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Inhibitory activities of Lignum Sappan extractives on growth and growth-related signaling of tumor cells 被引量:5
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作者 ZHANG Qing LIU Jing-Li +2 位作者 QI Xiao-Man QI Chun-Ting YU Qiang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2014年第8期607-612,共6页
AIM: To investigate the active constituents of Lignum Sappan(Caesalpinia sappan L.) on growth-related signaling and cell mitosis. METHOD: The influence of the ethyl acetate(EtOAc) extract of Lignum Sappan and its cons... AIM: To investigate the active constituents of Lignum Sappan(Caesalpinia sappan L.) on growth-related signaling and cell mitosis. METHOD: The influence of the ethyl acetate(EtOAc) extract of Lignum Sappan and its constituents on growth-related signaling were evaluated by a luciferase assay in cells stably- transfected with NF-κB, STAT1, or STAT3 responsive luciferase reporter plasmid. The inhibitory effect on the cell cycle was determined by flow cytometric analysis. The anti-tumor activities were assessed in vitro and in vivo. RESULTS: The EtOAc extract of Lignum Sappan had inhibitory activities on growth-related signaling and cell mitosis. Three major active compounds were sappanchalcone, brazilin, and butein. Sappanchalcone blocked cell cycle progression in the G2/M phase, brazilin inhibited TNFα/NF-κB signaling, while butein inhibited IL-6/STAT3 signaling, as well as TNFα/NF-κB signaling. The three compounds all demonstrated cytotoxic activities against human tumor cells in vitro. In a S180 tumor cell-bearing mice model, the anti-tumor efficacy of the EtOAc extract was better than the individual compounds acting alone. CONCLUSION: These results indicate that Lignum Sappan contains multiple active compounds with different antitumor activities, which act synergistically to enhance their anti-tumor effects. The EtOAc extract of Lignum Sappan may be better than individual active constituent as a novel medicine for the treatment of cancer. 展开更多
关键词 Caesalpinia sappan L. Lignum Sappan Anti-tumor activity Cell cycle blocker Signaling pathway inhibitor SYNERGY
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Dietary bioactives and essential oils of lemon and lime fruits 被引量:2
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作者 Siyu Liu Shiming Li Chi-Tang Ho 《Food Science and Human Wellness》 SCIE 2022年第4期753-764,共12页
Human beings have consumed lemon(Citrus limon)and lime(Citrus aurantifolia or Citrus latiflia)for thousands of years.Among the variety of citrus families,lemon and lime are originated from the hybridization of citron ... Human beings have consumed lemon(Citrus limon)and lime(Citrus aurantifolia or Citrus latiflia)for thousands of years.Among the variety of citrus families,lemon and lime are originated from the hybridization of citron with primitive papeda,hence they are similar from the nutritional and organoleptic standpoints,whereas very different from other citrus species such as orange and mandarin.Except for fresh produce,a signifi cant percentage of lemon and lime are processed and separated as juice,essential oils,pulps and other products.Lemon and lime juice or fruit itself is rich in vitamins,minerals and flavonoids which are rich sources for human nutrition.Consumption of lemon and lime fruit or juice are benefi cial for human health in the scope of urinary citrate increase,oxidative stress relief,improvement in lipid profi les and infl ammation markers,neuroprotective effects among others.These beneficial effects of lemon and lime are not only because of their high vitamin C content but also other bioactive micronutrients such as fl avonoids.Essential oils from lemon and lime have fresh and zesty aroma for perfumery and flavor applications for centuries.Compared with orange or mandarin,the integrated review for lemon and lime dietary bioactive compounds and essential oils is scarce.Therefore,in this review,we introduced the historical cultivation,consumption and process of lemon and lime,discussed the chemical and biological activities of phytochemicals in lemon and lime fruits and juice,and summarized volatile and non-volatile components in lemon and lime oil.This review may provide a comprehensive perspective for entire lemon and lime industry as well as their scientifi c values. 展开更多
关键词 LEMON LIME Essential oils FLAVONOIDS Biological activity
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Characterization and anticancer potential of Withania somnifera fruit bioactives(a native species to Pakistan)using gas chromatography-mass spectrometer,nuclear magnetic resonance and liquid chromatography-mass spectrometry-electrospray ionization 被引量:1
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作者 Qudsia Tabassam Tahir Mehmood +2 位作者 Sibtain Ahmed Farooq Anwar Abdul Rauf Raza 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2022年第6期908-914,共7页
INTRODUCTION:Withania somnifera(W.somnifera)is a plant with remarkable pharmacological properties.The plant has an impressive profile of medicinal uses in the folk medicine system of several civilizations.AIM:This com... INTRODUCTION:Withania somnifera(W.somnifera)is a plant with remarkable pharmacological properties.The plant has an impressive profile of medicinal uses in the folk medicine system of several civilizations.AIM:This comprehensive study is aimed to characterize phytochemicals in fruit of W.somnifera and tested for in vitro anticancer potential to find out active candidate in disease prevention and treatment.METHODS:The bioactive components from W.somnifera fruit were extracted with polar and non-polar solvents.Anticancer potential of the isolated bioactive was assessed against different cancer cell lines through MTT assay and Incucytes imaging analysis.The extracts were characterized for secondary metabolites using GCMS(gas chromatography-mass spectrometer),LCMS(liquid(electrospray Ionization)and 1H-NMR(electrospray Ionization)techniques.RESULTS:Both freeze-dried and rotary evaporator condensed extracts exhibited anticancer potential against MDA-MB-231,MCF7-SKOV3 and SKBR3 cell lines.The tested extracts have cell growth inhibition potential against mammalian cancer cell line.Hexacosanedioic acid purified from n-hexane extract through HPLC was investigated for its cytotoxicity against breast cancer cell line SKBR3 by using Incucytes imaging analysis.Conclusion:We found that a variety of bioactive compounds existed in this plant.One identified compound that was not investigated for cytotoxicity in previous studies was purified and its application showed cytotoxicity on breast cancer cell lines.A number of bioactive identified from W.somnifera fruit may have an effective potential for development into chemotherapy drugs. 展开更多
关键词 PHYTOCHEMICALS plants MEDICINAL anti-cancer activities purification state-of-the-art techniques
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Dead Sea Minerals-Induced Positive Stress as an Innovative Resource for Skincare Actives 被引量:1
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作者 Meital Portugal-Cohen Maria F. Dominguez +2 位作者 Miriam Oron Robert Holtz Ze’evi Ma’or 《Journal of Cosmetics, Dermatological Sciences and Applications》 2015年第1期22-35,共14页
Objective: Exposure to certain stresses in small doses might lead to a protective effect by improving resistance to other stressors. Dead Sea (DS) minerals can be a relevant source to induce positive stress due to the... Objective: Exposure to certain stresses in small doses might lead to a protective effect by improving resistance to other stressors. Dead Sea (DS) minerals can be a relevant source to induce positive stress due to their high salinity and unique mineral combination. This concept could be further optimized using advanced unique cell biotechnology. The purpose of this study was to elucidate the innovative concept of DS minerals (water extract and black mud) supplementation in small amount to Pichia pastoris yeast growth media as a positive stress by testing the capability of accepted fermentation compounds to affect the appearance of skin. Methods: Skin equivalents were topically applied with different Pichia pastoris fermentations (Metabiotics?). Skin elasticity biomarkers were tested, since loss of elasticity and suppleness is a natural skin aging process leading to deeper wrinkles and loss of firmness. A preliminary screening at the gene level using DNA microarray was performed and subsequently, the following proteins were detected using ELISA or immunoblotting assays: elastin, fibulin-1, lysyl oxidase (LOX), metalloproteinase 3 (MMP-3), E-cadherin, claudin 4, tight junction protein (TJP)-1 and TJP-2. UVB irradiation was selected as a stressor. Results: Fermentation compounds generated in the presence of small doses of DS minerals affected the expression of various elasticity-related genes in skin. Moreover, they significantly attenuated the abnormal UVB-induced alterations, the proteins elastin, fibulin-1, LOX, MMP-3, E-cadherin and TJP-2. Conclusions: The observations clearly demonstrate that when DS Metabiotics? compounds are topically applied, significant alterations in several biomarkers that contribute to skin elasticity occur. Thus, these novel compounds have the potential to serve as skincare actives. 展开更多
关键词 SKIN Elasticity Biomarkers SKIN Aging Active INGREDIENTS DEAD Sea MINERALS POSITIVE STRESS
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Bioguided Fractionation and Purification of Natural Bioactives Obtained from<i>Alpinia conchigera</i>Water Extract with Melanin Inhibition Activity
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作者 Zanariah Binti Ujang Thavamanithevi Subramaniam +4 位作者 Mazita Md Diah Harmayumi Binti Wahid Badariah Binti Abdullah Ahmad Hazri Bin Abd Rashid David Appleton 《Journal of Biomaterials and Nanobiotechnology》 2013年第3期265-272,共8页
Crude extracts of Alpinia conchigera a species from the Malaysian Ginger (Zingiberaceae) family and its fractions obtained from various extraction methods were assayed for melanogenesis inhibition activity and cell vi... Crude extracts of Alpinia conchigera a species from the Malaysian Ginger (Zingiberaceae) family and its fractions obtained from various extraction methods were assayed for melanogenesis inhibition activity and cell viability. The crude extract obtained from the ethanolic extraction and the super critical fluid extraction did not exhibit significant melanin inhibition activity and was shown to be toxic to the melanocyte cells in comparison to the water extract. The crude aqueous extracts displayed melanin inhibition of 96.38 ± 1.60% and cell viability 109.90 ± 8.32% at a concentration of 500 μg/mL. Bioassay guided fractionation was performed on the water extracts to isolate the active compounds. The actives were identified as trans-cinnamaldehyde and chavicol glucopyranoside with both compound showing potent anti-melanogenesis activity. At 4.9 μg/ml, both trans-cinnamaldehyde and chavicol glucopyranoside gave 85% inhibition of melanin formation in vitro with 77% and 97% cell viability respectively. In comparison, kojic acid, a known skin lightening agent showed 90.0% inhibition at 100 μg/mL. The bioactive composition comprising the extract, active fraction, purified compounds or mixture thereof of Alpinia conchigera may be used for cosmetic and pharmaceutical applications, particularly for the purposes of reducing skin pigmentation. 展开更多
关键词 ALPINIA Conchigera Preparatory HPLC FRACTIONATION Chavicol GLUCOPYRANOSIDE Trans Cinnamaldehyde Anti-Melanogenesis ACTIVITY
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Overexpression of the inwardly rectifying potassium channel Kir4.1 or Kir4.1 Tyr^(9)Asp in Müller cells exerts neuroprotective effects in an experimental glaucoma model 被引量:1
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作者 Fang Li Zhen Li +6 位作者 Shuying Li Hong Zhou Yunhui Guo Yongchen Wang Bo Lei Yanying Miao Zhongfeng Wang 《Neural Regeneration Research》 2026年第4期1628-1640,共13页
Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apopt... Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma. 展开更多
关键词 apoptosis chronic ocular hypertension glial cell activation Kir4.1 overexpression Kir4.1 Tyr^(9)Asp mutation microglia Müller cells NEUROINFLAMMATION neuroprotection retinal ganglion cells
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Pressurized physically activated carbon used as a high-performance,low cost cathode material in lithium–sulfur batteries
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作者 Minghao Wang Zhangxiao +4 位作者 Gao Hongye Hata Satoshi Nakabayashi Koji Yoon Seongho Miyawaki Jin 《新型炭材料(中英文)》 北大核心 2026年第1期127-141,共15页
Lithium–sulfur(Li–S)batteries are promisingcandidates for next-generation energy storagegiven their high energy density and potential low cost.Chemically activated carbon(CAC)is often used fortheir cathodes,because ... Lithium–sulfur(Li–S)batteries are promisingcandidates for next-generation energy storagegiven their high energy density and potential low cost.Chemically activated carbon(CAC)is often used fortheir cathodes,because it has a high specific surfacearea for sulfur loading.We have developed a pressurizedphysical activation(PPA)method that producedan activated carbon(PPAC)with a high specific surfacearea comparable to that of CAC.The pore structure of PPAC could be changed and its use as a cathode material for Li–Sbatteries was investigated.Battery tests at different capacity rates(C-rates)showed that it had a much improved high-rate performancewith a discharge capacity of 900 mAh/(g of sulfur)at 1 C,in contrast to only 600 mAh/(g of sulfur)for CAC.Porestructure analyses showed that PPAC prepared at a high activation temperature(1000℃)had unusual channel-like mesoporesbetween the microdomains that are the basic structural units of artificial carbon materials.These are connected to microporesdeveloped in each microdomain,and deliver ions from the surroundings to the internal pores and vice versa.The well-developedmicropores and mesopores of PPAC respectively ensured the high adsorption of lithium polysulfides and a high rate ofion diffusion.Compared to CAC,PPAC is a high-performance,low-cost cathode material that is promising for use in futureLi–S batteries. 展开更多
关键词 Activated carbon Pressurized physical activation Mesoporous channel Lithium-sulfur batteries MICRODOMAIN
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Hot Compression Deformation Behavior and Processing Maps of Mg-Zn-Mn(-Sn)-Ca Alloy
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作者 Chen Xia Zhu Yulong +2 位作者 Liu Quanyi Zhang Dingfei Pan Fusheng 《稀有金属材料与工程》 北大核心 2026年第3期627-635,共9页
The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from... The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from 0.001 s^(-1) to 1 s^(-1).The results show that the addition of Sn promotes dynamic recrystallization(DRX),and CaMgSn phases can act as nucleation sites during the compression deformation.Flow stress increases with increasing the strain rate and decreasing the temperature.Both the ZM61-0.5Ca and ZMT612-0.5Ca alloys exhibit obvious DRX characteristics.CaMgSn phases can effectively inhibit dislocation motion with the addition of Sn,thus increasing the peak fl ow stress of the alloy.The addition of Sn increases the hot deformation activation energy of the ZM61-0.5Ca alloy from 199.654 kJ/mol to 276.649 kJ/mol,thus improving the thermal stability of the alloy.For the ZMT612-0.5Ca alloy,the optimal hot deformation parameters are determined to be a deformation temperature range of 350–400℃and a strain rate range of 0.001–0.01 s^(-1). 展开更多
关键词 hot deformation constitutive equation processing map deformation activation energy magnesium alloy
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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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Health Phys.Abstracts,Volume 129,Number 4
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《辐射防护》 北大核心 2026年第1期87-91,共5页
Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,... Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,and Wei-hao Qin1(1.National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing,100088,China.) 展开更多
关键词 nuclear medicine workers health physics carbon cartridge internal dose assessment analysis method I activity
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Prescribed-Time Active Disturbance Rejection Control for Electromagnetic Formation Flight Under Model Uncertainties and Disturbances
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作者 SHEN Xixi MENG Bin HU Jiangping 《空间控制技术与应用(中英文)》 北大核心 2026年第1期94-102,共9页
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ... This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller. 展开更多
关键词 electromagnetic formation prescribed time active disturbance rejection control output feedback control
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A review of the surface activation and modification of biochars
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作者 Zhang Yihan Chen Longyi 《新型炭材料(中英文)》 北大核心 2026年第1期67-90,共24页
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen... Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed. 展开更多
关键词 Activation and modification Carbon material interface Surface functionalization Metal nanoparticle deposition Surface defect
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/AC catalyst NH_(3)-SCR performance
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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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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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Comprehensive review of the pharmacological potential of Passiflora incarnata L.:neuropsychiatric,antioxidant,antimicrobial,and anticancer activities
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作者 Balasubramanian Deepika Koyeli Girigoswami 《Traditional Medicine Research》 2026年第4期11-26,共16页
Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive com... Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine. 展开更多
关键词 Passiflora incarnata L ANTI-DEPRESSANT antioxidant activity antimicrobial activity anti-anxiety activity anticancer activity
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Pyrimidine derivatives in discovery of pesticides:A review
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作者 Haokun Yuan Anjing Liao +3 位作者 Shunhong Chen Yiming Tian Yaming Liu Jian Wu 《Chinese Chemical Letters》 2026年第2期145-158,共14页
Pyrimidine is a widely used compound in pesticides and medicine,with over 60 commercial pesticides containing a pyrimidine structure.Examples include the insecticide flufenerim,herbicide nicosulfuron,fungicide mepanip... Pyrimidine is a widely used compound in pesticides and medicine,with over 60 commercial pesticides containing a pyrimidine structure.Examples include the insecticide flufenerim,herbicide nicosulfuron,fungicide mepanipyrim,antiviral agent ningnanmycin,and plant growth regulator ancymidol.This paper reviews the characteristics from 2014 to 2024 of highly active pyrimidine-containing compounds and their biological activities,focusing on insecticidal,herbicidal,antibacterial,antiviral,and plant growth regulation properties.The goal is to provide insights for the design and synthesis of new pyrimidine-based pesticide candidates. 展开更多
关键词 Pyrimidine compounds Insecticidal activity Herbicidal activity Antifungicidal activity Antiviral activity Plant growth regulator
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An Overview of Drag Reduction Methods in Road Cars
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作者 Umberto Ravelli Silvia Ravelli 《Fluid Dynamics & Materials Processing》 2026年第2期1-41,共41页
Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection... Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection of studies was presented to focus on the most important aerodynamic features of the flow around realistic car body shapes.Then,the discussion was organized around three pillars related to passive flow control,active flow control and active aerodynamics.Both experimental and numerical investigations were included to provide a comprehensive overview.A clear distinction was made between simplified and realistic car models,as well as production vehicles(within the limits of restricted access information).Moreover,a short essay was dedicated to electric vehicles,for which aerodynamics matters,especially at highway speeds.Last,the impact of aerodynamic principles on the design of current and future vehicle fleet was assessed,honestly admitting that recent market trends must be reversed to turn decarbonization goals into reality and damp the effects of global warming. 展开更多
关键词 Road cars AERODYNAMICS drag coefficient passive flowcontrol active flowcontrol active aerodynamics
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