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Andrographolide inhibits NF-KB activation and attenuates neointimal hyperplasia in arterial restenosis 被引量:11
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作者 YuJiu Wang Jin Tao Wang +1 位作者 QuanXin Fan Jian Guo Geng 《Cell Research》 SCIE CAS CSCD 2007年第11期933-941,共9页
The NF-kB transcription factors modulate the expression of tissue factor (TF), E-selectin (CD62E) and vascular cell adhesion molecule-1 (VCAM-1), which are essential for thrombosis and inflammation. We have prev... The NF-kB transcription factors modulate the expression of tissue factor (TF), E-selectin (CD62E) and vascular cell adhesion molecule-1 (VCAM-1), which are essential for thrombosis and inflammation. We have previously shown that andrographolide (Andro) covalently modifies the reduced cysteine^62 of p50-a major subunit of NF-kB transcription factors, thus blocking the binding of NF-kB transcription factors to the promoters of their target genes, preventing NF-kB activation and inhibiting inflammation in vitro and in vivo. Here we report that Andro, but not its inactive structural analog 4H-Andro, significantly suppressed the proliferation of arterial neointima (-60% reduction) in a murine model of arterial restenosis. Consistently, p50^-/- mice manifested attenuated neointimal hyperplasia upon arterial ligation. Notably, the same dosage of Andro did not further reduce neointimal formation in p50^-/- mice, which implicates the specificity of Andro on p50 for treating experimental arterial restenosis. The upregulation of NF-kB target genes, including TF, E-selectin and VCAM-1, and the increased deposition of leukocytes (mainly CD68^+ macrophages) were clearly detected within the injured arterial walls, all of which were significantly abolished by treatment with Andro or genetic deletion of p50. The expression ofTF, E-selectin and VCAM-I was also markedly upregulated in the patient sample of thrombotic vasculitis, indicating the clinical relevance of NF-kB activation in the pathogeneses of occlusive arterial diseases. Our data thus indicate that, by the downregulation of the NF-kB target genes that are critical in thrombosis and inflammation, specific inhibitors of p50, such as Andro, may be therapeutically valuable for preventing and treating thrombotic arterial diseases, including neointimal hyperplasia in arterial restenosis. 展开更多
关键词 nf-kb transcription factors ANDROGRAPHOLIDE neointimal hyperplasia arterial restenosis TF E-SELECTIN VCAM-I
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4', 6-Dihydroxy-4-methoxyisoaurone inhibits TNF-α-induced NF-KB activation and expressions of NF-KB-regulated target gene products
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期27-27,共1页
The nuclear factor-KB (NF-KB) transcription factors control many physiological processes including in- flammation, immunity, apoptosis, and angiogenesis. In our search for NF-KB inhibitors from natural resources, we... The nuclear factor-KB (NF-KB) transcription factors control many physiological processes including in- flammation, immunity, apoptosis, and angiogenesis. In our search for NF-KB inhibitors from natural resources, we identified 4',6-dihydroxy-4-methoxyisoaurone (ISOA) as an inhibitor of NF-KB activation from the seeds of Tricho- santhes kirilowii. However, the mechanism by which ISOA inhibits NF-KB activation is not fully understood. In the present study, we demonstrated the effect of ISOA on NF-KB activation in TNF-α-stimulated HeLa cells. This com- pound suppressed NF-KB activation through the inhibition of IKB kinase (IKK) activation. ISOA also has an influ- ence on upstream signaling of IKK through the inhibition of expression of adaptor proteins, TNF receptor-associated factor 2 (TRAF2) and receptor interacting protein 1 (RIP1). Consequently, ISOA blocked the phosphorylation and degradation of the inhibitor of NF-KB alpha (IKBα) , and subsequent phosphorylation and nuclear translocation of p65. The suppression of NF-KB activation by ISOA led to the down-regulation of target genes involved in inflam- mation, proliferation, angiogenesis and invasion, as well as potentiation of TNF-α-induced apoptosis at least in part through activation of caspase-8. Taken together, this study extends our understanding on the mechanisms underly- ing the anti-inflammatory and anti-cancer activities of ISOA. Our findings provide new insight into the molecular mechanisms and a potential application of ISOA for inflammatory diseases as well as certain cancers associated with abnormal NF-KB activation. 展开更多
关键词 4' 6-dihydroxy-4-methoxyisoaurone nf-kb IKK IKBΑ P65 apoptosis
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Tuning beneficial calcineurin phosphatase activation to counterα-synuclein toxicity in a yeast model of Parkinson’s disease
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作者 Srishti Chawla Mikael Molin Thomas Nystrom 《Neural Regeneration Research》 SCIE CAS 2025年第1期199-200,共2页
Calcineurin(CN)is a calcium-and calmodulindependent serine/threonine that has been studied in many model organisms including yeast,filamentous fungi,plants,and mammals.Its biological functions range from ion homeostas... Calcineurin(CN)is a calcium-and calmodulindependent serine/threonine that has been studied in many model organisms including yeast,filamentous fungi,plants,and mammals.Its biological functions range from ion homeostasis and virulence in lower eukaryotes to T-cell activation in humans by human nuclear factors of activated T-cells.CN is a heterodimeric protein consisting of a catalytic subunit,calcineurin A(Cna1p),which contains an active site with a dinuclear metal center,and a regulatory Ca^(2+) binding subunit called calcineurin B(Cnb1p)required to activate Cna1p.The calcineurin B subunit has been highly conserved through evolution:For example,the mammalian calcineurin B shows 54%identity with calcineurin B from Saccharomyces cerevisiae. 展开更多
关键词 activation DINUCLEAR CONSERVED
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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes
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作者 Ying Wang Kai Zhang +10 位作者 Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期548-558,共11页
Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid ... Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid boron.In this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B system.This approach can be adopted to form various low-melting-point AM–Mg–B–O growth systems.These growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN chains.These findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs. 展开更多
关键词 Boron nitride nanotubes LOW-TEMPERATURE Boron activation Density functional theory
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Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test
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作者 Skyla Stifter Jessie McCaffrey +2 位作者 Tyler Nichols Ayse Ozcan Edeer Justine Ward 《World Journal of Methodology》 2025年第1期95-104,共10页
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor... BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing. 展开更多
关键词 External cue Internal cue Muscle activation Core muscles Lumbopelvic stability Pressure biofeedback unit
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Strategies to achieve effective nitrogen activation 被引量:2
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作者 Bin Chang Huabin Zhang +1 位作者 Shuhui Sun Gaixia Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期137-163,共27页
Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few... Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few years.Although some achievements have been revealed in aqueous NRR,significant challenges have also been identified.The activity and selectivity are fundamentally limited by nitrogen activation and competitive hydrogen evolution.This review focuses on the hurdles of nitrogen activation and delves into complementary strategies,including materials design and system optimization(reactor,electrolyte,and mediator).Then,it introduces advanced interdisciplinary technologies that have recently emerged for nitrogen activation using high-energy physics such as plasma and triboelectrification.With a better understanding of the corresponding reaction mechanisms in the coming years,these technologies have the potential to be extended in further applications.This review provides further insight into the reaction mechanisms of selectivity and stability of different reaction systems.We then recommend a rigorous and detailed protocol for investigating NRR performance and also highlight several potential research directions in this exciting field,coupling with advanced interdisciplinary applications,in situ/operando characterizations,and theoretical calculations. 展开更多
关键词 activation via mediators catalyst optimization electrochemical nitrogen fixation high-energy activation of nitrogen NITROGEN
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Brain-wide activation involved in 15 mA transcranial alternating current stimulation in patients with first-episode major depressive disorder 被引量:1
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作者 Jie Wang Wenfeng Zhao +8 位作者 Huang Wang Haixia Leng Qing Xue Mao Peng Baoquan Min Xiukun Jin Liucen Tan Keming Gao Hongxing Wang 《General Psychiatry》 CSCD 2024年第2期265-273,共9页
Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely un... Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely unknown.Aims To investigate which intracranial brain structures are engaged in the tACS at 77.5 Hz and 15 mA,delivered via the forehead and the mastoid electrodes in the human brain.Methods Actual human head models were built using the magnetic resonance imagings of eight outpatient volunteers with drug-naïve,first-episode major depressive disorder and then used to perform the electric field distributions with SimNIBS software.Results The electric field distributions of the sagittal,coronal and axial planes showed that the bilateral frontal lobes,bilateral temporal lobes,hippocampus,cingulate,hypothalamus,thalamus,amygdala,cerebellum and brainstem were visibly stimulated by the 15 mA tACS procedure.Conclusions Brain-wide activation,including the cortex,subcortical structures,cerebellum and brainstem,is involved in the 15 mA tACS intervention for first-episode major depressive disorder.Our results indicate that the simultaneous involvement of multiple brain regions is a possible mechanism for its effectiveness in reducing depressive symptoms. 展开更多
关键词 STIMULATION INVOLVEMENT activation
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Salidroside Attenuates LPS-stimulated Activation of THP-1 Cell-derived Macrophages through Down-regulation of MAPK/NF-kB Signaling Pathways 被引量:10
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作者 王洪武 吴婷 +3 位作者 齐俊英 王亚琦 罗小平 宁琴 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第4期463-469,共7页
Summary: Excessive activation of macrophages is implicated in various inflammatory injuries. Salidroside (Sal), one of the main bioactive components ofRhodiola Sachalinensis, has been reported to possess anti-infla... Summary: Excessive activation of macrophages is implicated in various inflammatory injuries. Salidroside (Sal), one of the main bioactive components ofRhodiola Sachalinensis, has been reported to possess anti-inflammatory activities. This study aimed to examine the effect of Sal on the activa- tion of macrophages and the possible mechanism. The lipopolysaccharide (LPS)-stimulated phrobol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophage models were established. The changes in the inflammatory profiles of THP-l-derived macrophages were determined. The results showed that Sal significantly decreased the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), interleukin-lbeta (IL-1β), interleukin-6 (IL-6) and tumor necrosis fac- tor-or (TNF-a) at both mRNA and protein levels in THP-l-derived macrophages, and the effect was dose-depedent. Moreover, NF-B activation was significantly suppressed and the phosphorylation of ERK, p38 and JNK was substantially down-regulated after Sal treatment. The findings suggested that Sal can suppress the activation of LPS-stimulated PMA-differetiated THP-1 cells, as evidenced by the decreased expression of iNOS, COX2, IL-1β, IL-6 and TNF-a, and the mechanism involves the inhibition of NF-r,B activation and the phosphorylation of the MAPK signal pathway. 展开更多
关键词 SALIDROSIDE THP-1 MAPK LPS nf-kb
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Thermal pretreatment of willow branches impacts yield and pore development of activated carbon in subsequent activation with ZnCl_(2) via modifying cellulose structure
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作者 Linghui Kong Chao Li +7 位作者 Runxing Sun Shu Zhang Yi Wang Jun Xiang Song Hu Dong Wang Chuanjun Leng Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期227-237,共11页
Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce d... Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce dehydration and/or aromatization to change the structure of cellulose/hemicellulose.This might interfere with evolution of structures of AC,which was investigated herein via thermal pretreatment of willow branch(WB)from 200 to 360℃and the subsequent activation with ZnCl_(2) at 550℃.The results showed that thermal pretreatment at 360℃(WB-360)could lead to substantial pyrolysis to form biochar,with a yield of 31.9%,accompanying with nearly complete destruction of cellulose crystals and remarkably enhanced aromatic degree.However,cellulose residual in WB-360 could still be activated to form AC-360 with specific surface area of 1837.9 m~2·g^(-1),which was lower than that in AC from activation of untreated WB(AC-blank,2077.8 m~2·g^(-1)).Nonetheless,the AC-200 from activation of WB-200 had more developed pores(2113.9 m~2·g^(-1))and superior capability for adsorption of phenol,due to increased permeability of ZnCl_(2) to the largely intact cellulose structure in WB-200.The thermal pretreatment did increase diameters of micropores of AC but reduced the overall yield of AC(26.8%for AC-blank versus 18.0%for AC-360),resulting from accelerated cracking but reduced intensity of condensation.In-situ infrared characterization of the activation showed that ZnCl_(2) mainly catalyzed dehydration,dehydrogenation,condensation,and aromatization but not cracking,suppressing the formation of derivatives of cellulose and lignin in bio-oil.The thermal pretreatment formed phenolic-OH and C=O with higher chemical innerness,which changed the reaction network in activation,shifting morphology of fibrous structures in AC-blank to“melting surface”in AC-200 or AC-280. 展开更多
关键词 Thermal pretreatment activation with ZnCl_(2) Willow branch activated carbon Biochar
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Acid mine drainage activation mechanism on lime-depressed pyrite flotation from copper sulfide ore
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作者 Jia-qiao YUAN Zhan DING +3 位作者 Yun-xiao BI Jie LI Shu-ming WEN Shao-jun BAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2987-3001,共15页
The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of l... The lime-depressed pyrite from Cu differential flotation tailings with acid mine drainage(AMD)as a natural activator was recovered.The effect of AMD on lime-depressed pyrite flotation was investigated by a series of laboratory flotation tests and surface analytical techniques.Flotation test results indicated that AMD could effectively activate the pyrite flotation with a sodium butyl xanthate(SBX)collector,and a high-quality sulfur concentrate was obtained.Pulp ion concentration analysis results indicated that AMD facilitated desorption of Ca^(2+)and adsorption of Cu^(2+)on the depressed-pyrite surface.Adsorption measurements and contact angle analysis results confirmed that adding AMD improved the adsorption amount of SBX collector on the pyrite surface and increased the contact angle by 31°.Results of Raman spectroscopy and X-ray photoelectron spectroscopy analysis indicated that AMD treatment promoted the formation of hydrophobic species(S^(0) hydrophobic entity and copper sulfides)and the removal of hydrophilic calcium and iron species on the pyrite surface,which reinforced the adsorption of collector.The findings of the present research provide important theoretical basis and technical support for a cleaner production of copper sulfide ores. 展开更多
关键词 copper sulfur ore acid mine drainage lime-depressed pyrite FLOTATION natural activator activation mechanism
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Zonal activation of molecular carbon dioxide and hydrogen over dual sites Ni-Co-MgO catalyst for CO_(2) methanation:Synergistic catalysis of Ni and Co species
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作者 Zonglin Li Jianjun Chen +8 位作者 Yu Xie Junjie Wen Huiling Weng Mingxue Wang Jingyi Zhang Jinyan Cao Guocai Tian Qiulin Zhang Ping Ning 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期213-225,共13页
An in-depth mechanism in zonal activation of CO_(2)and H2molecular over dual-active sites has not been revealed yet.Here,Ni-Co-MgO was rationally constructed to elucidate the CO_(2)methanation mechanism.The abundant s... An in-depth mechanism in zonal activation of CO_(2)and H2molecular over dual-active sites has not been revealed yet.Here,Ni-Co-MgO was rationally constructed to elucidate the CO_(2)methanation mechanism.The abundant surface nickel and cobalt components as active sites led to strong Ni-Co interaction with charge transfer from nickel to cobalt.Notably,electron-enriched Coδ-species participated in efficient chemisorption and activation of CO_(2)to generate monodentate carbonate.Simultaneously,plentiful available Ni0sites facilitated H2dissociation,thus CO_(2)and H2were smoothly activated at zones of Coδ-species and Ni0,respectively.Detailed in situ DRIFTS,quasi situ XPS,TPSR,and DFT calculations substantiated a new formate evolution mechanism via monodentate carbonate instead of traditional bidentate carbonate based on synergistic catalysis of Coδ-species and Ni0.The zonal activation of CO_(2)and H2by tuning electron behaviors of double-center catalysts can boost heterogeneous catalytic hydrogenation performance. 展开更多
关键词 Zonal activation CO_(2) methanation Dual active sites Synergistic effect
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Using microglia-derived extracellular vesicles to capture diversity of microglial activation phenotypes following neurological injury
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作者 Austyn D.Roseborough Nikita Ollen-Bittle Shawn NWhitehead 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1633-1634,共2页
Microglia are one of the three glial cell populations in the central nervous system(CNS),along with astrocytes and oligodendrocytes.While microglia are unique among brain cells due to their hematologic origin and perf... Microglia are one of the three glial cell populations in the central nervous system(CNS),along with astrocytes and oligodendrocytes.While microglia are unique among brain cells due to their hematologic origin and perform immune functions similar to peripheral macrophages,they are not simply macrophages of the CNS. 展开更多
关键词 NEUROLOGICAL cytes activation
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The impact of maternal immune activation on the morphology and electrophysiological properties of postnatally-born neurons in the offspring
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作者 Emilio J.Galván Angelica Zepeda 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期399-400,共2页
Pregnancy comes with a combination of physical changes and physiological immunosuppression that increases the susceptibility of women to pathogens and in turn,rises the prevalence of infectious diseases.
关键词 PREVALENCE activation impact
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Experimental study on the activation of coal gasification fly ash from industrial CFB gasifiers
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作者 Qiyao Yang Xiaobin Qi +1 位作者 Qinggang Lyu Zhiping Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期8-18,共11页
Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environmen... Coal gasification fly ash(CGFA)is an industrial solid waste from the coal circulating fluidized bed(CFB)gasification process,and it needs to be effectively disposed to achieve sustainable development of the environment.To realize the application of CGFA as a precursor of porous carbon materials,the physicochemical properties of three kinds of CGFA from industrial CFB gasifiers are analyzed.Then,the activation potential of CGFA is acquired via steam activation experiments in a tube furnace reactor.Finally,the fluidization activation technology of CGFA is practiced in a bench-scale CFB test rig,and its advantages are highlighted.The results show that CGFA is characterized by a high carbon content in the range of 54.06%–74.09%,an ultrafine particle size(d50:16.3–26.1 μm),and a relatively developed pore structure(specific surface area SSA:139.29–551.97 m^(2)·g^(-1)).The proportion of micropores in CGFA increases gradually with the coal rank.Steam activation experiments show that the pore development of CGFA mainly includes three stages:initial pore development,dynamic equilibrium between micropores and mesopores and pore collapse.The SSA of lignite fly ash(LFA),subbituminous fly ash(SBFA)and anthracite fly ash(AFA)is maximally increased by 105%,13%and 72%after steam activation;the order of the largest carbon reaction rate and decomposition ratio of steam among the three kinds of CGFA is SBFA>LFA>AFA.As the ratio of oxygen to carbon during the fluidization activation of LFA is from 0.09 to 0.19,the carbon conversion ratio increases from 14.4%to 26.8%and the cold gas efficiency increases from 6.8%to 10.2%.The SSA of LFA increases by up to 53.9%during the fluidization activation process,which is mainly due to the mesoporous development.Relative to steam activation in a tube furnace reactor,fluidization activation takes an extremely short time(seconds)to achieve the same activation effect.It is expected to further improve the activation effect of LFA by regulating the carbon conversion ratio range of 27%–35%to create pores in the initial development stage. 展开更多
关键词 Circulating fluidized bed Coal gasification fly ash Steam activation Pore structure evolution Fluidization activation
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Properties of Activated Carbons from Sugarcane Leaves and Rice Straw Derived Charcoals by Activation at Low Temperature via KMnO_(4)Pre-Oxidation-Hydrolysis
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作者 Sumrit Mopoung Narissara Namkaew and Sasiwan Srikasaem 《Journal of Renewable Materials》 EI CAS 2024年第8期1433-1454,共22页
Activated carbon preparation from sugarcane leaves and rice straw by carbonization(250℃–400℃)and activation at 500℃were studied.The effects of pre-oxidation,hydrolysis of derived charcoals by boiled KMnO4 aqueous ... Activated carbon preparation from sugarcane leaves and rice straw by carbonization(250℃–400℃)and activation at 500℃were studied.The effects of pre-oxidation,hydrolysis of derived charcoals by boiled KMnO4 aqueous solution were evaluated.The derived charcoals products were pretreated using oxidation-hydrolysis with 1–5 wt.%KMnO4 at 100℃and then activated at 500℃.The derived charcoal and activated carbon products were characterized by FTIR,XRD,SEM-EDS and BET.Iodine number and methylene blue number of derived products were also used for the analysis of the products.It was found that fabricated charcoal materials made at 350℃–400℃possess good characteristics with low content of surface functional groups and high carbon content.After pre-oxidation-hydrolysis and activation at 500℃,the resulting derived activated carbon materials from charcoals with 400℃carbonization temperature have high content of oxygen containing surface functional groups such as Mn-O,Si-O,Si-O-Si,C-O,or O-H.In addition,MnO_(2) accumulated on the surface of the derived activated carbon products.The surface area and pore volume of the activated carbon products have also increased with increasing of KMnO_(4) concentration from 1 to 3 wt.%and then decreased with 5 wt.%used during activation.Therefore,activated carbon products made by pre-oxidation-hydrolysis with 3 wt.%KMnO_(4) were used for Fe(Ⅲ)adsorption experiments.It was found that Fe(Ⅲ)adsorption on the activated carbon materials can be fitted with both the Freundlich and the Langmuir models.The calculated maximum Fe(Ⅲ)adsorption capacities of sugarcane leaves derived activated carbon and rice straw derived activated carbon products were 50.00 and 39.37 mg/g,respectively.It was shown that the effect of pre-oxidation-hydrolysis by KMnO_(4) and activation at 500℃are beneficial for activated carbon preparation with environmentally friendly and low-cost simplified operation. 展开更多
关键词 activated carbon potassium permanganate pre-oxidation-hydrolysis low carbonization temperature low activation temperature
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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan Zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang Ping Zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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Activation of IP10/CXCR3 Signaling is Highly Coincidental with PrP^(Sc)Deposition in the Brains of Scrapie-Infected Mice
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作者 Chen Jia Chen Cao +6 位作者 Hu Chao Yang Wei Wang Lin Chen Dongdong Wu Yuezhang Shi Qi Dong Xiaoping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第11期1235-1251,共17页
Objective To analyze the relationship between Chemokine IP10 and its receptor CXCR3 during prion infection.Methods We investigated the increases in IP10 signals,primarily localized in neurons within the brains of scra... Objective To analyze the relationship between Chemokine IP10 and its receptor CXCR3 during prion infection.Methods We investigated the increases in IP10 signals,primarily localized in neurons within the brains of scrapie-infected mice,using western blotting,ELISA,co-immunoprecipitation,immunohistochemistry,immunofluorescence assays,and RT-PCR.Results Both CXCR3 levels and activation were significantly higher in the brains of scrapie-infected mice and prion-infected SMB-S15 cells.Enhanced CXCR3 expression was predominantly observed in neurons and activated microglia.Morphological colocalization of PrPC/PrPSc with IP10/CXCR3 was observed in scrapie-infected mouse brains using immunohistochemistry and immunofluorescence.immunohistochemistry(IHC)analysis of whole brain sections further revealed increased accumulation of IP10/CXCR3 specifically in brain regions with higher levels of PrPSc deposits.Co-immunoprecipitation and biomolecular interaction assays revealed the molecular interactions between PrP and IP10/CXCR3.Notably,a significantly larger amount of IP10 accumulated within prion-infected SMB-S15 cells than in the normal partner cell line,SMB-PS.Importantly,resveratrol treatment effectively suppressed prion replication in SMB-S15 cells,thereby restoring the accumulation and secretion pattern of cellular IP10 similar to that observed in SMB-PS cells.Conclusion Our data demonstrate that the activation of IP10/CXCR3 signaling in prion-infected brain tissues coincides with PrPSc deposition.Modulation of IP10/CXCR3 signaling in the brain represents a potential therapeutic target for mitigating the progression of prion diseases. 展开更多
关键词 PRION Chemokine IP10 CXCR3 activation
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Ultra-high specific surface area activated carbon from Taihu cyanobacteria via KOH activation for enhanced methylene blue adsorption
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作者 Yifang Mi Wenqiang Wang +4 位作者 Sen Zhang Yalong Guo Yufeng Zhao Guojin Sun Zhihai Cao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期106-116,共11页
Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu cyanobacteria.When the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs ... Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu cyanobacteria.When the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs possessed an ultra-high specific surface(2178.90 m^(2)·g^(-1))and plenty of micro-and meso-pores,as well as a high pore volume(1.01 cm^(3)·g^(-1)).Ascribed to ultra-high surface area,π-π interaction,electrostatic interaction,as well as hydrogen-bonding interactions,the CBACs displayed huge superiority in efficient dye removal.The saturated methylene blue adsorption capacity by CBACs could be as high as 1143.4 mg·g^(-1),superior to that of other reported biomass-activated carbons.The adsorption was endothermic and modeled well by the pseudo-second-order kinetic,intra-particle diffusion,and Langmuir models.This work presented the effectiveness of Taihu cyanobacteria adsorbent ascribed to its super large specific surface area and high adsorption ability. 展开更多
关键词 activated carbon BIOMASS Dye adsorption Taihu cyanobacteria
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Effect of Na_(2)CO_(3)Roasting Activation on Acid Leaching Property of Fly Ash
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作者 LIU Chenjia ZHAO Aichun +4 位作者 YE Xin ZHAO Zi ZHANG Tingan YANG Xiaorong QIN Yanmei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1613-1620,共8页
By using high-alumina fly ash as raw material,a process was proposed for activating the fly ash with Na_(2)CO_(3)calcination and extracting aluminum from activated clinker with sulfuric acid leaching.The feasibility o... By using high-alumina fly ash as raw material,a process was proposed for activating the fly ash with Na_(2)CO_(3)calcination and extracting aluminum from activated clinker with sulfuric acid leaching.The feasibility of roasting process of activated fly ash by Na_(2)CO_(3)was discussed based on thermodynamic analysis.The experimental results showed that Na_(2)CO_(3)gradually reactes with mullite over 700 K to produce NaAlSiO_(4).The optimal process conditions for the activation stage are:a material ratio of 1:1 between sodium carbonate and fly ash,a calcination temperature of 900℃,and a calcination time of 2.5 hours.Under these conditions,the leaching rate of aluminum is 90.3%.By comparing the SEM and XRD analysis of raw and clinker materials,it could be concluded that the mullite phase of fly ash is almost completely destroyed and transformed into sodium aluminosilicate with good acid solubility. 展开更多
关键词 fly ash calcination activation acid leaching ALUMINUM
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Importance of V^(4)and optimal acid environment in the hydroxylation of inert benzene via activation of C_(sp2)-H bond
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作者 Peng Dong Yang Xin +6 位作者 Yanwei Li Xiaohui Zhang Xiaorui Wang Yu Zhao Dongqiang Zhang Haowen Ma Guixian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期216-226,共11页
Hydroxylation of inert benzene through the activation of the C_(sp2)-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds,which has far-reaching guiding significance but remains a cha... Hydroxylation of inert benzene through the activation of the C_(sp2)-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds,which has far-reaching guiding significance but remains a challenging scientific problem.To overcome this problem,a series of VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)were prepared to achieve an efficient and economical hydroxylation path of benzene to phenol.The results showed that the phenol yield was 72.89%(selectivity>98.1%)under the optimum conditions.The reason is that the C-H bond in the benzene ring is activated by heterolysis over a VOx-Ga_(2)O_(3)/SiO_(2)-Al_(2)O_(3)catalyst.Meanwhile,the introduction of aluminum(Al)and gallium(Ga)made a qualitative change in the catalyst,enhancing the electron motion and spin motion of vanadium species,resulting in the increase of V4^(+)/V5^(+)ratio.In addition,the catalyst can provide an optimal acidic environment and a threedimensional cross-linked surface structure that facilitates product diffusion. 展开更多
关键词 C_(sp2)-H activation V4^(+)/V5^(+)ratio Acid microenvironment Catalysis Support Catalyst activation
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