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Lanthanide complexes with β-diketones and coumarin derivates:synthesis,thermal behaviour,optical and pharmacological properties and immobilisation 被引量:2
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作者 Maria Milanova Joana Zaharieva +2 位作者 Iliya Manolov Miroslava Getzova Dimitr To dorovsky 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第S1期66-74,共9页
The paper presents the results of the synthesis of complexes of the ty pe Eu(DBM) 3 and Eu(DBM) 3·Q(DBM-dibenzoylmethane,Q-1,10-phenantroline or 4,7-d iphenyl-1,10-phenantroline) and of Tb-and Nd-complexes with t... The paper presents the results of the synthesis of complexes of the ty pe Eu(DBM) 3 and Eu(DBM) 3·Q(DBM-dibenzoylmethane,Q-1,10-phenantroline or 4,7-d iphenyl-1,10-phenantroline) and of Tb-and Nd-complexes with the newly-synthesis ed coumarin derivates 3,3’-[(4-chlorphenyl) methylene) bis(4-hydroxy-2H-chromen-2-one) ,3,3’-[(3,5-dimethoxy-4-hydroxy) methylene) bis(4-hydroxy-2H-chromen-2-one) ,etc. Elemental and thermogravimetric analysis,IR,UV,NMR and fluorescence spe ctroscopy and X-ray analysis were applied for characterisation of the complexes. Some peculiarities of the synthetic procedures for both types of complexes were discussed and the influence of the synthetic approach,pH of the reaction mediu m,temperature of synthesis and drying of the complexes on the composition,stab ility and optical properties was reported. The immobilisation of the complexes i n thin films based on sol-gel produced SiO2 and on polymethylmethacrylate was st udied. The optimal conditions for preparation of the matrices(composition of th e starting system,temperature and time of sol aging,etc.) were recommended. Th e film morphology was evaluated by fluorescence,scanning electron and atomic fo rce microscopy. The interaction of the lanthanide ions with the matrices and the influence of their nature,the effect of the in-situ polymerisation and other f actors on photoluminescent excitation and emission spectra and excited state lif e-times of the complexes were followed. The effect of the second ligand on the p hotoluminescence properties of the immobilised diketonates was further elucidate d. Processes involved in the thermal decomposition of the complexes and microcom posites produced on their base were proposed. Preliminary results on the pharmac ological properties of the coumarin complexes reported showed unambiguously high er cytotoxicity of the Nd complex in comparison with that of the respective ligand. 展开更多
关键词 rare earths COMPLEXES thin films β-diketones coumarin derivates optical properties pharmacological properties MORPHOLOGY
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Corrosion Inhibition of Imidazoline Derivates with Benzene Rings on Mild Steel in CO_2-Saturated Brine Solution 被引量:2
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作者 CHEN Guo-hao ZHAO Jing-mao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期691-695,共5页
Corrosion inhibition of three imidazoline derivates with different numbers of benzene rings,namely 2-phenyl-1-ethylamino imidazoline(CI-1),2-phenyl-1-ethylamino-1-methylbenzyl quaternary imidazoline(CI-12) and 2-p... Corrosion inhibition of three imidazoline derivates with different numbers of benzene rings,namely 2-phenyl-1-ethylamino imidazoline(CI-1),2-phenyl-1-ethylamino-1-methylbenzyl quaternary imidazoline(CI-12) and 2-phenyl-1-benzoyl ethylamino imidazoline(CI-13),on mild steel in CO2-saturated brine solution was evaluated by mass-loss method and potentiodynamic polarization method.The results show that the three imidazoline derivates can inhibit CO2 corrosion effectively with CI-12 ranking the highest.They mainly restrain the anodic dissolution and act as anodic-type inhibitors.The adsorptions of these derivates on the mild steel surface follow the Langmuir adsorption isothermal equation and belong to chemical adsorption. 展开更多
关键词 Corrosion inhibitor CO2 corrosion Langmuir adsorption Imidazoline derivate
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Trinuclear Metal Complexes Based on 1,10-Phenanthroline Derivates as Catalysts for Cleavage of a RNA-Model Substrate
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作者 XU Xin-he LIN Hai LIN Hua-kuan  《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期493-499,共7页
Two multidentate ligands 2,9-di[6'-(2″-hydroxyl-3″-methoxyphenyl)-n-2',5'-diazahexyl]-1,10-phenanthroline(LA)and 2,9-di(6'-α-phenol-n-2',5'-diazahexyl)-1,10-phenanthroline(LB)were synthesized and full... Two multidentate ligands 2,9-di[6'-(2″-hydroxyl-3″-methoxyphenyl)-n-2',5'-diazahexyl]-1,10-phenanthroline(LA)and 2,9-di(6'-α-phenol-n-2',5'-diazahexyl)-1,10-phenanthroline(LB)were synthesized and fully characterized.Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated.The trinuclear metal complexes [Cu(Ⅱ)and Zn(Ⅱ)] of the ligands were studied,as catalysts,for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p-nitrophenyl phosphate(HPNP).The second-order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained,which indicated that Zn3LBH-1 was the most efficient catalyst among them.The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP. 展开更多
关键词 (:eywords Trinuclear metal complex 1 10-Phenanthroine derivate Catalyst Cleavage of RNA-model substrate
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Corrosion Inhibition Studies of Benzoxazole Derivates for N80 Steel in 1 M HCl Solution: Synthesis, Experimental, and DTF Studies
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作者 Dongqiu Yang Xiaojun Feng +5 位作者 Ning Yan Yanqun Wang Lilin Lu Ping Mei Wu Chen Lu Lai 《Open Journal of Yangtze Oil and Gas》 2022年第2期101-123,共23页
Three benzoxazole corrosion inhibitors, namely 2-(benzo [d]oxazol-2-yl)phenol (BOP), 6-(benzo [d]oxazol-2-yl)pyridin-2-ol (BOPO), and 2-(quinolin-2-yl) benzo [d]oxazole (QBO), were synthesized. Moreover, their corrosi... Three benzoxazole corrosion inhibitors, namely 2-(benzo [d]oxazol-2-yl)phenol (BOP), 6-(benzo [d]oxazol-2-yl)pyridin-2-ol (BOPO), and 2-(quinolin-2-yl) benzo [d]oxazole (QBO), were synthesized. Moreover, their corrosion inhibition performance for N80 steel in 1 M HCl solution at 303 K was measured by the electrochemical measurements and surface analysis studies. The results show that the inhibition efficiency of all corrosion inhibitors increases with the increase of concentration. At the same concentration, the order of inhibition efficiency is BOP < BOPO < QBO. Moreover, the studied inhibitors act as mixed-type inhibitors, and the adsorption of all inhibitors on N80 steel followed the Langmuir adsorption isotherm. Further, we have examined the effect of iodide ions on inhibition efficiency. The results show that BOP and KI are synergistic, BOPO and QBO are competitive adsorptions with KI. The quantum chemical parameters such as highest occupied molecular orbital, lowest unoccupied molecular orbital energy levels, and energy gap were calculated by the density functional theory (DTF). The relations between the inhibition efficiency and some quantum parameters have been discussed. The protective effect of the three inhibitors followed the sequence of BOP < BOPO < QBO. The results obtained from quantum chemicals and electrochemical were in reasonable agreement. 展开更多
关键词 N80 Steel Benzoxazole Derivatives Corrosion Inhibition Electrochemical Measurements DFT
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Application of metal-organic frameworks,covalent organic frameworks and their derivates for the metal-air batteries 被引量:7
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作者 Yunyun Xu Hairong Xue +6 位作者 Xijuan Li Xiaoli Fan Peng Li Tengfei Zhang Kun Chang Tao Wang Jianping He 《Nano Research Energy》 2023年第2期130-150,共21页
Metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)as the novel porous materials have the merits of diverse,adjustable functionality,high porosity and surface area,which have great application prospect... Metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)as the novel porous materials have the merits of diverse,adjustable functionality,high porosity and surface area,which have great application prospects in the gas storage,separation and catalysis.In addition,their derivates make up for the insufficient of electronic conductivity and chemical stability of MOFs and COFs,and provide a new ideal for accurate control of material structure.Up to now,many efficient electrocatalysts have been designed based on MOFs,COFs and their derivates for O_(2)reduction/evolution reactions(ORR/OER)and CO_(2)reduction/evolution reactions(CO_(2)RR/CO_(2)ER)in the metal-air batteries.In this review,the latest development of MOFs,COFs and their derivates in the metal-air batteries is summarized,and we discuss the structural characteristics of these materials and their corresponding mechanisms of action.By comprehensively reviewing the advantages,challenges and prospects of MOFs and COFs,we hope that the organic framework materials will shed more profound insights into the development of electrocatalysis and energy storage in the future. 展开更多
关键词 metal-organic frameworks covalent organic frameworks the derivates ELECTROCATALYSIS metal-air batteries
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Mitochondria-derived vesicles:New players in the game of neurodegeneration
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作者 Laura Palumbo Domenico Nuzzo +1 位作者 Antonella Girgenti Pasquale Picone 《Neural Regeneration Research》 2026年第2期679-680,共2页
Introduction:One of the main events that regulate a cell’s well-being is cell-to-cell communication.This intercellular mechanism of information transfer is often mediated by vesicular trafficking.Mitochondrial-derive... Introduction:One of the main events that regulate a cell’s well-being is cell-to-cell communication.This intercellular mechanism of information transfer is often mediated by vesicular trafficking.Mitochondrial-derived vesicles(MDVs)are an emerging subpopulation of extracellular vesicle(EV)first discovered in 2008 that allow mitochondria to communicate with their surroundings. 展开更多
关键词 extracellular vesicles cell cell communication vesicular traffickingmitochondrial derived NEURODEGENERATION mitochondria derived vesicles vesicular trafficking extracellular vesicle ev first
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Spray-dried MOF-derived bimetallic oxide/carbon hybrids with superior electron transfer capability for catalyzing ammonium perchlorate decomposition
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作者 Tianjin Zhi Dongze Li +3 位作者 Yan Li Zhenxin Yi Shunguan Zhu Lin Zhang 《Defence Technology(防务技术)》 2026年第1期224-240,共17页
The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performa... The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performance improvement of kinds of catalysts.In this study,bimetallic metal-organic frameworks(MOFs),such as CuCo-BTC(BTC=1,3,5-Benzenetricarboxylic acid,H_(3)BTC),CuNi-BTC,and CoNi-BTC,were synthesized by solvothermal(ST)and spray-drying(SD)methods,and then calcined at 400℃for 2 h to form metal oxides.The catalysts as well as their catalytic effects for AP decomposition were characterized by FTIR,XRD,SEM,XPS,TG,DSC,TG-IR,EIS,CV,and LSV.It was found that the rapid coordination of metal ions with ligands during spray drying may lead to catalytic structural defects,promoting the exposure of reactive active sites and increasing the catalytic active region.The results showed that the addition of 2 wt%binary transition metal oxides(BTMOs)as catalysts significantly reduced the high-temperature decomposition(HTD)temperature of AP and enhanced its heat release.Of particular significance is the observation that SD-CoNiO_(x),prepared by spray-drying,reduced the decomposition temperature of AP from 413.26℃(pure AP)to 306℃and enhanced the heat release from 256.79 J/g(pure AP)to 1496.82 J/g,while concomitantly reducing the activation energy by 42%.By analysing the gaseous products during the decomposition of AP+SD-CoNiO_(x)and AP+ST-CoNiO_(x),it was found that SD-CoNiO_(x)could significantly increase the content of high-valent nitrogen oxides during the AP decomposition reaction,which indicates that the BTMOs prepared by spray-drying in the reaction system are more conducive to accelerating the electron transfer in the thermal decomposition process of AP,and can provide a high concentration of reactive oxygen species that oxidize AP to high-valent nitrogen oxide-containing compounds.The present study shows that the structure selectivity of the spray-drying technique influences surfactant molecular arrangement on catalyst surfaces,resulting in their ability to promote higher electron transfer during the catalytic process.Therefore,BTMOs prepared by spray drying method have higher potential for application. 展开更多
关键词 Metal-organic framework derivatives Combustion catalyst Binary transition metal oxides Ammonium perchlorate
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Electrochromic Devices with High Stability from Colorless to Green Conversion Based on Viologen Derivatives
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作者 PENG Yuyi QIAN Chao +3 位作者 WANG Peng GUO Xu JIANG Chuanyu LIU Ping 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期258-267,共10页
Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)... Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]di-hexafluorophosphate(Bn-FPV),were synthesized.These viologen derivatives as active materials were used to assemble both flexible and rigid electrochromic devices(ECDs).ECDs based on DFPV exhibited reversible color change from colorless to deep green and ECDs based on Bn-FPV exhibited reversible color change from colorless to blue-green within applied voltage.It was found that the devices based on DFPV showed cycle stability,which could still maintain more than 90% after 1000 cycles.In addition,the modulation rate of the device to the solar irradiance is also calculated to characterize its application potential in smart windows.Among them,the rigid device(R-DFPV)based on the DFPV has a large solar irradiance modulation rate of 54.66%,which has the potential to be used as smart windows. 展开更多
关键词 viologen derivatives electrochromic material flexible electrochromic devices rigid electrochromic device smart windows
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Effects and mechanisms of adipose tissue-derived extracellular vesicles in vascular inflammation and dysfunction
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作者 Daphne Lintsen Bieke Broux 《Neural Regeneration Research》 2026年第5期2005-2006,共2页
Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated ... Neuroinflammation is a key process in the pathogenesis of various neurodegenerative diseases,such as multiple sclerosis(MS),Alzheimer's disease,and traumatic brain injury.Even for disorders historically unrelated to neuroinflammation,such as Alzheimer's disease,it is now shown to precede pathological protein aggregations. 展开更多
关键词 pathological protein aggregations vascular inflammation NEUROINFLAMMATION neurodegenerative diseasessuch multiple sclerosis Alzheimers disease adipose tissue derived extracellular vesicles alzheimers diseaseit
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Effect of Magnetic Hysteresis on Magnon-Magnon Coupling Induced by Interlayer Dzyaloshinskii-Moriya Interaction
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作者 Jihao Xia Yuqiang Wang +8 位作者 Guibin Lan Jiyang Ou Weizhou Wu Jiafeng Feng Caihua Wan Guanxiang Du Syed Rizwan Xiufeng Han Guoqiang Yu 《Chinese Physics Letters》 2026年第1期231-247,共17页
Based on the Smit-Suhl formula,we propose a universal approach for solving the magnon-magnon coupling problem in bilayer coupled systems(e.g.,antiferromagnets).This method requires only the energy expression,enabling ... Based on the Smit-Suhl formula,we propose a universal approach for solving the magnon-magnon coupling problem in bilayer coupled systems(e.g.,antiferromagnets).This method requires only the energy expression,enabling the automatic derivation of analytical expressions for the eigenmatrix elements via symbolic computation,eliminating the need for tedious manual calculations.Using this approach,we investigate the impact of magnetic hysteresis on magnon-magnon coupling in a system with interlayer Dzyaloshinskii-Moriya interaction(DMI).The magnetic hysteresis leads to an asymmetric magnetic field dependence of the resonance frequency and alters the number of degeneracy points between the pure optical and acoustic modes.Moreover,it can result in the coupling strength at the gap of the f–H phase diagram being nearly vanishing,contrary to the conventionally expected maximum.These results deepen the understanding of the effect of interlayer DMI on magnon–magnon coupling and the proposed universal method significantly streamlines the solving process of magnon–magnon coupling problems. 展开更多
关键词 universal approach magnon magnon coupling symbolic computationeliminating magnetic hysteresis bilayer coupled systems egantiferromagnets energy expressionenabling derivation analytical expressions interlayer Dzyaloshinskii Moriya interaction
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Induced pluripotent stem cell-derived mesenchymal stem cells enhance acellular nerve allografts to promote peripheral nerve regeneration by facilitating angiogenesis
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作者 Fan-Qi Meng Chao-Chao Li +14 位作者 Wen-Jing Xu Jun-Hao Deng Yan-Jun Guan Tie-Yuan Zhang Bo-Yao Yang Jian Zhang Xiang-Ling Li Feng Han Zhi-Qi Ren Shuai Xu Yan Liang Wen Jiang Jiang Peng Yu Wang Hai-Ying Liu 《Neural Regeneration Research》 2026年第5期2050-2059,共10页
Previous research has demonstrated the feasibility of repairing nerve defects through acellular allogeneic nerve grafting with bone marrow mesenchymal stem cells.However,adult tissue–derived mesenchymal stem cells en... Previous research has demonstrated the feasibility of repairing nerve defects through acellular allogeneic nerve grafting with bone marrow mesenchymal stem cells.However,adult tissue–derived mesenchymal stem cells encounter various obstacles,including limited tissue sources,invasive acquisition methods,cellular heterogeneity,purification challenges,cellular senescence,and diminished pluripotency and proliferation over successive passages.In this study,we used induced pluripotent stem cell-derived mesenchymal stem cells,known for their self-renewal capacity,multilineage differentiation potential,and immunomodulatory characteristics.We used induced pluripotent stem cell-derived mesenchymal stem cells in conjunction with acellular nerve allografts to address a 10 mm-long defect in a rat model of sciatic nerve injury.Our findings reveal that induced pluripotent stem cell-derived mesenchymal stem cells exhibit survival for up to 17 days in a rat model of peripheral nerve injury with acellular nerve allograft transplantation.Furthermore,the combination of acellular nerve allograft and induced pluripotent stem cell-derived mesenchymal stem cells significantly accelerates the regeneration of injured axons and improves behavioral function recovery in rats.Additionally,our in vivo and in vitro experiments indicate that induced pluripotent stem cell-derived mesenchymal stem cells play a pivotal role in promoting neovascularization.Collectively,our results suggest the potential of acellular nerve allografts with induced pluripotent stem cell-derived mesenchymal stem cells to augment nerve regeneration in rats,offering promising therapeutic strategies for clinical translation. 展开更多
关键词 acellular nerve allograft ANGIOGENESIS bioluminescence imaging conditioned medium induced pluripotent stem cell–derived mesenchymal stem cells micro-CT scanning Microfil perfusion peripheral nerve injury
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Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
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作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
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戊糖片球菌CQFP202437对抗生素诱导小鼠运动机能失调的调节作用机制
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作者 李科 易若琨 《食品工业科技》 北大核心 2025年第10期383-390,共8页
本研究旨在探究戊糖片球菌CQFP202437对抗生素诱导小鼠运动失调的保护作用,探讨益生菌的作用效果和机理。使用无菌处理后的混合抗生素溶液腹腔注射构建小鼠运动失调模型,造模结束后测定各组小鼠跑步和游泳等运动参数的变化以及小鼠血清... 本研究旨在探究戊糖片球菌CQFP202437对抗生素诱导小鼠运动失调的保护作用,探讨益生菌的作用效果和机理。使用无菌处理后的混合抗生素溶液腹腔注射构建小鼠运动失调模型,造模结束后测定各组小鼠跑步和游泳等运动参数的变化以及小鼠血清和脑组织中丙二醛(Malondialdehyde,MDA),超氧化物歧化酶(Superoxide Dismutase,SOD)、还原型谷胱甘肽(Reduced Glutathione,GSH),小鼠白细胞介素(Interleukin-6,IL-6、Interleukin-10,IL-10)和肿瘤坏死因子(Tumor Necrosis Factor-α,TNF-α);小鼠盲肠肠道屏障基因Occludin-1、ZO-1和Claudin-1的mRNA相对表达量;小鼠脑组织中CREB、ERK1/2和BDNF基因的mRNA相对表达量。结果显示,与模型组相比,戊糖片球菌CQFP202437显著提升了小鼠游泳和跑步的时间(P<0.01),显著(P<0.05)降低小鼠大脑中炎症因子IL-6、TNF-α的水平,增加小鼠大脑中SOD的表达,减少小鼠大脑和血清中MDA的累积。并且戊糖片球菌CQFP202437能提升小鼠大脑组织中BDNF代谢通路相关基因BDNF、ERK1/2、CREB的表达,增强BDNF的作用,还能上调盲肠组织中Occludin-1基因表达。结果表明,戊糖片球菌CQFP202437对抗生素诱导小鼠运动机能失调有调节作用,为提升运动机能益生菌制剂的研制和开发提供理论依据。 展开更多
关键词 戊糖片球菌 跑台运动 负重游泳 脑源性神经因子(Brain Derived Neurophic Factor BDNF)
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Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis 被引量:2
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作者 Xiahong Tang Nan Zheng +8 位作者 Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1103-1123,共21页
Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to impr... Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning. 展开更多
关键词 bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria NEUROINFLAMMATION oxidative stress PYROPTOSIS reactive oxygen species
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Impact of pitch fraction oxidation on the structure and sodium storage properties of derived carbon materials 被引量:1
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作者 QI Su-xia YANG Tao +6 位作者 SONG Yan ZHAO Ning LIU Jun-qing TIAN Xiao-dong WU Jin-ru LI Hui LIU Zhan-jun 《新型炭材料(中英文)》 北大核心 2025年第2期421-439,共19页
Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation ac... Pitch produced by the lique-faction of coal was divided into two frac-tions:soluble in toluene(TS)and insol-uble in toluene but soluble in pyridine(TI-PS),and their differences in molecu-lar structure and oxidation activity were studied.Several different carbon materi-als were produced from them by oxida-tion in air(350℃,300 mL/min)fol-lowed by carbonization(1000℃ in Ar),and the effect of the cross-linked structure on their structure and sodium storage properties was investigated.The results showed that the two pitch fractions were obviously different after the air oxidation.The TS fraction with a low degree of condensation and abundant side chains had a stronger oxidation activity and thus introduced more cross-linked oxygen-containing functional groups C(O)―O which prevented carbon layer rearrangement during the carbonization.As a result,a disordered hard carbon with more defects was formed,which improved the electrochemical performance.Therefore,the carbon materials derived from TS(O-TS-1000)had an obvious disordered structure and a larger layer spacing,giving them better sodium storage perform-ance than those derived from the TI-PS fraction(O-TI-PS-1000).The specific capacity of O-TS-1000 was about 250 mAh/g at 20 mA/g,which was 1.67 times higher than that of O-TI-PS-1000(150 mAh/g). 展开更多
关键词 Pitch fractions Air oxidation Derived carbon materials Na^(+)storage
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SiCN吸波陶瓷制备及改性方法的研究进展
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作者 杨一江 董永朋 +4 位作者 刘有云 唐舒 薛继梅 叶昉 范晓孟 《现代技术陶瓷》 2025年第3期360-376,共17页
新一代武器装备对高温隐身性能需求迫切,亟需发展高温吸波材料。SiCN陶瓷因其低密度、耐高温、介电性能可调等优势,作为高温吸波材料备受关注。本文对于SiCN陶瓷的研究进展进行了综述,首先介绍了SiCN陶瓷的制备方法,其中化学气相沉积制... 新一代武器装备对高温隐身性能需求迫切,亟需发展高温吸波材料。SiCN陶瓷因其低密度、耐高温、介电性能可调等优势,作为高温吸波材料备受关注。本文对于SiCN陶瓷的研究进展进行了综述,首先介绍了SiCN陶瓷的制备方法,其中化学气相沉积制备SiCN陶瓷所需温度较低,且制备出的SiCN陶瓷均匀致密;而聚合物转化陶瓷法具有良好的成型性和可加工性,近些年对于吸波SiCN陶瓷的研究制备主要是基于在此方法,故本文将重点围绕先驱体转化SiCN及其改性方法进行介绍。聚硅氮烷是聚合物先驱体转化SiCN的前驱体,可用来制备不同形态的SiCN陶瓷,其中SiCN气凝胶中的孔隙有利于电磁波的多次反射和散射,具有良好的吸波性能,而SiCN块体陶瓷以极化损耗为主,主要依赖自由碳和SiC纳米晶处形成的偶极子损耗电磁波,损耗机制单一,可从微观和宏观进行设计来优化吸波性能。根据损耗机制的不同,微观尺度改性可分为两类:一类是以磁性相改性为主,通过在聚硅氮烷前驱体中引入Fe、Co、Ni等实现磁电耦合以调节阻抗匹配并改善吸波性能;另一种以引入导电相或介电损耗相为主,通过引入碳纳米管、石墨烯和SiC纤维等来优化SiC陶瓷的吸波性能。宏观尺度上主要是通过对SiCN陶瓷进行周期性结构设计,构筑如由蜂窝状、空心球体状等亚波长结构单元组成的超材料,通过优化结构单元尺寸和形状以达到优化SiCN陶瓷吸波性能的目的。最后本文对于SiCN陶瓷及其复合材料未来发展趋势进行了展望。 展开更多
关键词 吸波 SiCN陶瓷 聚合物转化陶瓷(Polymer derived ceramic PDC) 陶瓷基复合材料
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Phase changes and electromagnetic wave absorption performance of XZnC(X=Fe/Co/Cu)loaded on melamine sponge hollow carbon composites 被引量:3
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作者 Xiubo Xie Ruilin Liu +4 位作者 Chen Chen Di Lan Zhelin Chen Wei Du Guanglei Wu 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期566-577,共12页
Non-stoichiometric carbides have been proven to be effective electromagnetic wave(EMW)absorbing materials.In this study,phase and morphology of XZnC(X=Fe/Co/Cu)loaded on a three dimensional(3D)network structure melami... Non-stoichiometric carbides have been proven to be effective electromagnetic wave(EMW)absorbing materials.In this study,phase and morphology of XZnC(X=Fe/Co/Cu)loaded on a three dimensional(3D)network structure melamine sponge(MS)carbon composites were investigated through vacuum filtration followed by calcination.The FeZnC/CoZnC/CuZnC with carbon nanotubes(CNTs)were uniformly dispersed on the surface of melamine sponge carbon skeleton and Co-containing sample exhibits the highest CNTs concentration.The minimum reflection loss(RL_(min))of the CoZnC/MS composite(m_(composite):m_(paraffin)=1:1,m represents mass)reached-33.60 dB,and the effective absorption bandwidth(EAB)reached 9.60 GHz.The outstanding electromagnetic wave absorption(EMWA)properties of the CoZnC/MS composite can be attributed to its unique hollow structure,which leads to multiple reflections and scattering.The formed conductive network improves dielectric and conductive loss.The incorporation of Co enhances the magnetic loss capability and optimizes interfacial polarization and dipole polarization.By simultaneously improving dielectric and magnetic losses,ex-cellent impedance matching performance is achieved.The clarification of element replacement in XZnC/MS composites provides an effi-cient design perspective for high-performance non-stoichiometric carbide EMW absorbers. 展开更多
关键词 electromagnetic wave absorption three dimensional network structure melamine sponge derived carbon non-stoichiometric carbide
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Curvularin derivatives from hydrothermal vent sediment fungus Penicillium sp.HL-50 guided by molecular networking and their antiinflammatory activity 被引量:2
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作者 Chunxue Yu Zixuan Xia +6 位作者 Zhipeng Xu Xiyang Tang Wenjuan Ding Jihua Wei Danmei Tian Bin Wu Jinshan Tang 《Chinese Journal of Natural Medicines》 2025年第1期119-128,共10页
Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid ... Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid of curvularin and purine.The structures and absolute configurations of compounds 1-9 were elucidated via nuclear magnetic resonance(NMR)spectroscopy,X-ray diffraction,electronic circular dichroism(ECD)calculations,^(13)C NMR calculation,modified Mosher's method,and chemical derivatization.Investigation of anti-inflammatory activities revealed that compounds 7-9,11,12,14,15,and 18 exhibited significant suppressive effects against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in murine macrophage RAW264.7 cells,with IC_(50)values ranging from 0.44 to 4.40μmol·L^(-1).Furthermore,these bioactive compounds were found to suppress the expression of inflammation-related proteins,including inducible NO synthase(i NOS),cyclooxygenase-2(COX-2),NLR family pyrin domain-containing protein 3(NLRP3),and nuclear factor kappa-B(NF-κB).Additional studies demonstrated that the novel compound 7 possessed potent antiinflammatory activity by inhibiting the transcription of inflammation-related genes,downregulating the expression of inflammation-related proteins,and inhibiting the release of inflammatory cytokines,indicating its potential application in the treatment of inflammatory diseases. 展开更多
关键词 Penicillium sp.HL-50 Curvularin derivatives Molecular networking Anti-inflammatory activity
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M2 macrophages-derived exosomes for osteonecrosis of femoral head treatment:modulating neutrophil extracellular traps formation and endothelial phenotype transition 被引量:2
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作者 Guanzhi Liu Ruomu Cao +5 位作者 Qimeng Liu Heng Li Peng Yan Kunzheng Wang Run Tian Pei Yang 《Bone Research》 2025年第4期855-865,共11页
Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed t... Exosomes have shown good potential in ischemic injury disease treatments.However,evidence about their effect and molecular mechanisms in osteonecrosis of femoral head(ONFH)treatment is still limited.Here,we revealed the cell biology characters of ONFH osteonecrosis area bone tissue in single cell scale and thus identified a novel ONFH treatment approach based on M2 macrophages-derived exosomes(M2-Exos).We further show that M2-Exos are highly effective in the treatment of ONFH by modulating the phenotypes communication between neutrophil and endothelium including neutrophil extracellular traps formation and endothelial phenotype transition.Additionally,we identified that M2-Exos’therapeutic effect is attributed to the high content of miR-93-5p and constructed miR-93-5p overexpression model in vitro and in vivo based on lentivirus and adenoassociated virus respectively.Then we found miR-93-5p can not only reduce neutrophil extracellular traps formation but also improve angiogenic ability of endothelial cells.These results provided a new theoretical basis for the clinical application of ONFH therapeutic exosomes. 展开更多
关键词 modulating phenotypes comm cell biology characters ischemic injury disease miR p osteonecrosis femoral neutrophil extracellular traps macrophages derived exosomes endothelial phenotype transition
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Co-regulation effect of solvation and interface of pyridine derivative enabling highly reversible zinc anode 被引量:1
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作者 Binrui Xu Guangbin Wang +3 位作者 Yong Liu Quanan Li Fengzhang Ren Jianmin Ma 《Journal of Materials Science & Technology》 2025年第1期1-9,共9页
The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions durin... The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions during cycling.Electrolyte additive modification is considered one of the most effective and simplest methods for solving the aforementioned problems.Herein,the pyridine derivatives(PD)including 2,4-dihydroxypyridine(2,4-DHP),2,3-dihydroxypyridine(2,3-DHP),and 2-hydroxypyrdine(2-DHP),were em-ployed as novel electrolyte additives in ZnSO_(4)electrolyte.Both density functional theory calculation and experimental findings demonstrated that the incorporation of PD additives into the electrolyte effectively modulates the solvation structure of hydrated Zn ions,thereby suppressing side reactions in AZIBs.Ad-ditionally,the adsorption of PD molecules on the zinc anode surface contributed to uniform Zn deposi-tion and dendrite growth inhibition.Consequently,a 2,4-DHP-modified Zn/Zn symmetrical cell achieved an extremely long cyclic stability up to 5650 h at 1 mA cm^(-2).Furthermore,the Zn/NH_(4)V_(4)O_(10)full cell with 2,4-DHP-containing electrolyte exhibited an outstanding initial capacity of 204 mAh g^(-1),with a no-table capacity retention of 79%after 1000 cycles at 5 A g^(-1).Hence,this study expands the selection of electrolyte additives for AZIBs,and the working mechanism of PD additives provides new insights for electrolyte modification enabling highly reversible zinc anode. 展开更多
关键词 Zn anode Pyridine derivative Electrolyte additive Solvation regulation Interface modification
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