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Using Small Punch Test to Investigate the Mechanical Properties of X42 Exposed to Gaseous Hydrogen:Effect of Pressure,Pre-charge Time,Punch Velocity and Oxygen Content
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作者 Hu-Yue Wang Hong-Liang Ming +3 位作者 Dong-Ceng Hou Jian-Qiu Wang Wei Ke En-Hou Han 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第11期1961-1983,共23页
This study investigated the effect of pressure,pre-charge time,punch velocity and oxygen content on the mechanical properties of X42 pipeline steel in gaseous hydrogen environment by using small punch test.When expose... This study investigated the effect of pressure,pre-charge time,punch velocity and oxygen content on the mechanical properties of X42 pipeline steel in gaseous hydrogen environment by using small punch test.When exposed to nitrogen,the fracture mode of X42 pipeline steel undergoes ductile fracture,but in the presence of hydrogen,it shifts to brittle fracture.Moreover,an increase in hydrogen pressure or a decrease in punch velocity is found to enhance the hydrogen embrittlement susceptibility of X42 pipeline steel,as evidenced by the decrease of maximal load,displacement at failure onset and small punch energy.But the effect of pre-charge time on the hydrogen embrittlement susceptibility of X42 pipeline steel is not very obvious.Meanwhile,the presence of oxygen has been found to effectively inhibit hydrogen embrittlement.As the oxygen content in hydrogen increases,the hydrogen embrittlement susceptibility of X42 pipeline steel decreases. 展开更多
关键词 X42 pipeline steel Hydrogen embrittlement Mechanical properties Scanning electron microscopy(SEM) Small punch test
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A recyclable covalent organic framework for selective removal of Hg(Ⅱ)and sunlight-driven sterilization in water
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作者 Mei Zhao Fengyang Zhao +8 位作者 Jiantao Ping Wenli Wu Lingxi Zhao Xinyue Luan Li Yu Shuhua Liu Yongxian Guo Juyoung Yoon Qiongzheng Hu 《Chinese Chemical Letters》 2025年第10期512-517,共6页
Mercury ions(Hg^(2+))and bacteria are widely spread in water pollution and pose a great threat to human health and the environment.Herein,a multifunctional COF Dmta Tph with significant Hg^(2+)adsorption capability an... Mercury ions(Hg^(2+))and bacteria are widely spread in water pollution and pose a great threat to human health and the environment.Herein,a multifunctional COF Dmta Tph with significant Hg^(2+)adsorption capability and continuous sunlight-driven sterilization property is designed and synthesized by introducing thioether and photosensitive porphyrin in a single molecule.The obtained COF displays a high Hg^(2+)adsorption capacity of 657.9 mg/g at 298 K and a superior antibacterial effect toward Escherichia coli and Staphylococcus aureus under sunlight irradiation.Mechanistic studies reveal that the strong coordination between S species and Hg^(2+)is the main driving force for high Hg^(2+)adsorption capability.The sterilization mechanism clarifies that the inactivation of bacteria is caused by1O_(2)produced from Dmta Tph with the assistance of light irradiation.Noteworthy,when Dmta Tph is applied in the treatment of wastewater,it displays high Hg^(2+)removal efficiency and remarkable antibacterial effect under complex conditions.This study has demonstrated a promising strategy for designing multifunctional COF-based materials,offering great potential in tackling the problem of heavy metal ions and bacteria pollution in water. 展开更多
关键词 Water treatment Covalent organic frameworks(COFs) Hg^(2+)adsorption Photodynamic sterilization THIOETHER Porphyrin
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Functional metabolomics analysis of the protective mechanism of total flavonoids of Scutellaria baicalensis on acute myocardial ischemia rats
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作者 Fang-Ying Tang Ru-Yi Ma +4 位作者 An-Yao Xiong Si-Tong Lin Xiao Wang Hong-Jing Dong Jian-Yong Zhang 《Traditional Medicine Research》 2025年第3期21-31,共11页
Background:The study aimed to investigate the protective effect and mechanism of total flavonoids of Scutellaria baicalensis(TFSB)on acute myocardial ischemia(AMI)rats by using functional metabonomics.Methods:Rats wer... Background:The study aimed to investigate the protective effect and mechanism of total flavonoids of Scutellaria baicalensis(TFSB)on acute myocardial ischemia(AMI)rats by using functional metabonomics.Methods:Rats were divided into the Control,Model,AMI positive control(Propranolol hydrochloride,30 mg/kg),low dose TFSB(50 mg/kg),and high dose TFSB(100 mg/kg)groups.Rats received the corresponding treatment by intragastric administration once daily for 10 consecutive days.Electrocardiogram,myocardial enzyme,triphenyltetrazolium chloride staining,hematoxylin-eosin,and enzyme-linked immunosorbent assay were performed to evaluate the protective effect of TFSB on AMI rats.Then,the UHPLC-Q-Orbitrap MS method based on serum metabolomics was utilised to search for metabolic biomarkers and metabolic pathways.Subsequently,Western blot and RT-PCR techniques were employed to identify the respective genes and proteins.Results:Pharmacodynamics revealed that TFSB could ameliorate AMI in rats.The results of the metabolomics analysis indicated that the alterations in metabolic profile observed in rats with AMI were partially improved by treatment with TFSB.Moreover,the mRNA expression levels of 5-lipoxygenase(5-LOX)and 15-lipoxygenase(15-LOX)and the protein expression levels of 5-LOX,15-LOX,interleukin-1β(IL-1β),and NF-κB p65 were reduced following treatment with TFSB.Conclusion:The potential treatment of TFSB in AMI may be ascribed to its ability to regulate arachidonic acid metabolism. 展开更多
关键词 total flavonoids of Scutellaria baicalensis acute myocardial ischemia liquid chromatography-mass spectrometry functional metabolomics MECHANISM
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A scalable approach to Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)@carbon/expanded graphite as cathode for ultralong-lifespan and low-temperature sodium-ion batteries
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作者 Zheng Li Fangkun Li +9 位作者 Xijun Xu Jun Zeng Hangyu Zhang Lei Xi Yiwen Wu Linwei Zhao Jiahe Chen Jun Liu Yanping Huo Shaomin Ji 《Chinese Chemical Letters》 2025年第10期616-622,共7页
Mixed polyanion phosphate Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP)is regarded as the most promising cathode material for sodium-ion batteries(SIBs),due to its high structural stability and low-cost environmental frien... Mixed polyanion phosphate Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP)is regarded as the most promising cathode material for sodium-ion batteries(SIBs),due to its high structural stability and low-cost environmental friendliness.However,its intrinsic low conductivity and sluggish Na^(+)diffusion restricted the fast-charge and low-temperature sodium storage.Herein,an NFPP composite encapsulated by in-situ pyrolytic carbon and coupled with expanded graphite(NFPP@C/EG)was constructed via a sol-gel method followed by a ballmill procedure.Due to the dual-carbon modified strategy,this NFPP@C/EG only enhanced the electronic conductivity,but also endowed more channels for Na^(+)diffusion.As cathode for SIBs,the optimized NFPP(M-NFPP@C/EG)delivers excellent rate capability(capacity of~80.5 mAh/g at 50 C)and outstanding cycling stability(11000 cycles at 50 C with capacity retention of 89.85%).Additionally,cyclic voltammetry(CV)confirmed that its sodium storage behavior is pseudocapacitance-controlled,with in-situ electrochemical impedance spectroscopy(EIS)further elucidating improvements in electrode reaction kinetics.At lower temperatures(0℃),M-NFPP@C/EG demonstrated exceptional cycling performance(8800 cycles at 10 C with capacity retention of 95.81%).Moreover,pouch cells also exhibited excellent stability.This research demonstrates the feasibility of a dual carbon modification strategy in enhancing NFPP and proposes a low-cost,high-rate,and ultra-stable cathode material for SIBs. 展开更多
关键词 Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7) Expanded graphite Dual-carbon modified Polyanionic compounds cathode Sodium-ion batteries
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Facile synthesis of magnetic covalent organic framework nanocomposites for the enrichment and quantification of trace organophosphorus pesticides in fruit juice
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作者 Quanbin Fu Xin Sun +4 位作者 Lu Liu Hailong Jiang Geoffrey I.N.Waterhouse Shiyun Ai Rusong Zhao 《Food Science and Human Wellness》 2025年第3期1106-1114,共9页
Organophosphorus pesticides(OPPs)in foods pose a serious threat to human health,motivating the development of novel analytical methods for their rapid detection and quantification.A magnetic covalent organic framework... Organophosphorus pesticides(OPPs)in foods pose a serious threat to human health,motivating the development of novel analytical methods for their rapid detection and quantification.A magnetic covalent organic framework(M-COF)adsorbent for the magnetic solid-phase extraction(MSPE)of OPPs from foods was reported.M-COF was synthesized by the Schiff base condensation reaction of 1,3,5-tris(4-aminophenyl)benzene and 4,4-biphenyldicarboxaldehyde on the surface of amino-functionalized magnetic nanoparticles.Density functional theory(DFT)calculations showed that adsorption of OPPs onto the surface of M-COF involved hydrophobic effects,van der Waals interactions,π-πinteractions,halogen-N bonding,and hydrogen bonding.Combined with gas chromatography-mass spectrometry(GC-MS)technology,the MSPE method features low limits of detection for OPPs(0.002-0.015μg/L),good reproducibility(1.45%-6.14%),wide linear detection range(0.01-1μg/L,R≥0.9935),and satisfactory recoveries(87.3%-110.4%).The method was successfully applied for the trace analysis of OPPs in spiked fruit juices. 展开更多
关键词 Covalent organic framework Gas chromatography-mass spectrometry Magnetic solid-phase extraction Organophosphorus pesticides Fruit juice
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Characterization of arsenate transformation and identification of arsenate reductase in a green alga Chlamydomonas reinhardtii 被引量:6
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作者 Xixiang Yin Lihong Wang +1 位作者 Guilan Duan Guoxin Sun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第7期1186-1193,共8页
Arsenic (As) is a pervasive and ubiquitous environmental toxin that has created catastrophic human health problems world-wide. Chlamydomonas reinhardtii is a unicellular green alga, which exists ubiquitously in fres... Arsenic (As) is a pervasive and ubiquitous environmental toxin that has created catastrophic human health problems world-wide. Chlamydomonas reinhardtii is a unicellular green alga, which exists ubiquitously in freshwater aquatic systems. Arsenic metabolism processes of this alga through arsenate reduction and sequent store and efflux were investigated. When supplied with 10 μmol/L arsenate, arsenic speciation analysis showed that arsenite concentration increased from 5.7 to 15.7 mg/kg dry weight during a 7-day period, accounting for 18%–24% of the total As in alga. When treated with different levels of arsenate (10, 20, 30, 40, 50 μmol/L) for 7 days, the arsenite concentration increased with increasing external arsenate concentrations, the proportion of arsenite was up to 23%–28% of the total As in alga. In efflux experiments, both arsenate and arsenite could be found in the efflux solutions. Additionally, the efflux of arsenate was more than that of arsenite. Furthermore, two arsenate reductase genes of C. reinhardtii (CrACR2s) were cloned and expressed in Escherichia coli strain WC3110 (?arsC) for the first time. The abilities of both CrACR2s genes to complement the arsenate- sensitive strain were examined. CrACR2.1 restored arsenate resistance at 0.8 mmol/L. However, CrACR2.2 showed much less ability to complement. The gene products were demonstrated to reduce arsenate to arsenite in vivo. In agreement with the complementation results, CrACR2.1 showed higher reduction ability than CrACR2.2, when treated with 0.4 mmol/L arsenate for 16 hr incubation. 展开更多
关键词 ARSENATE ACCUMULATION REDUCTION EFFLUX arsenate reductase Chlamydomonas reinhardtii
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Visualizing the spatial distribution and alteration of metabolites in continuously cropped Salvia miltiorrhiza Bge using MALDI-MSI 被引量:5
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作者 Chenglong Sun Li Cui +3 位作者 Bingqian Zhou Xiao Wang Lanping Guo Wei Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第5期719-724,共6页
Salvia miltiorrhiza Bge(SMB)has long been used in traditional Chinese medicine to treat cardiovascular and cerebrovascular diseases.Growing clinical usage has led to a huge demand for artificial planting of SMB.Thus,c... Salvia miltiorrhiza Bge(SMB)has long been used in traditional Chinese medicine to treat cardiovascular and cerebrovascular diseases.Growing clinical usage has led to a huge demand for artificial planting of SMB.Thus,continuous cropping of SMB is an important challenge that needs to be addressed.Continuous cropping can alter the metabolic profile of plants,resulting in poor growth and low yield.In this study,we tried to image the spatial location and variation of endogenous metabolites in continuously cropped SMB using matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDIMSI).Spatially resolved expressions of tanshinones,salvianolic acids,polyamines,phenolic acids,amino acids,and oligosaccharides in normal and continuously cropped SMB roots were compared.The expressions of dihydrotanshinone Ⅰ,tanshinone Ⅱ A,dehydromiltirone,miltirone,dehydrotanshinone ⅡA,spermine,salvianolic acid B/E,tetrasaccharide,and pentasaccharide in continuously cropped SMB roots were much lower than those in normal roots.There was little difference in the expressions of caffeic acid and salvianolic acid A in normal and continuously cropped SMB roots.Ferulic acid was more widely distributed in xylem of normal SMB but strongly expressed in xylem,phloem,and cambium of continuously cropped SMB.The spatially resolved metabolite information enhances our understanding of the metabolic signature of continuously cropped SMB and also provides insights into the metabolic effects of continuous cropping in other plants. 展开更多
关键词 METABOLITES Spatial distribution and alteration Continuous cropping Salvia miltiorrhiza Bge MALDI-MSI
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Disaster reduction stick equipment: A method for monitoring and early warning of pipeline-landslide hazards 被引量:6
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作者 YAN Yan YANG Da-shen +4 位作者 GENG Dong-xian HU Sheng WANG Zi-ang HU Wang YIN Shu-yao 《Journal of Mountain Science》 SCIE CSCD 2019年第12期2687-2700,共14页
Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national e... Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national economy.Landslides are the most harmful type of pipeline accident,and have directed increasing public attention to safety issues.Although some useful results have been obtained in the investigation and prevention of pipeline-landslide hazards,there remains a need for effective monitoring and early warning methods,especially when the complexity of pipeline-landslides is considered.Because oil and gas pipeline-landslides typically occur in the superficial soil layers,monitoring instruments must be easy to install and must cause minimal disturbance to the surrounding soil and pipeline.To address the particular characteristics of pipelinelandslides,we developed a multi-parameter integrated monitoring system called disaster reduction stick equipment.In this paper,we detail this monitoring and early warning system for pipeline-landslide hazards based on an on-site monitoring network and early warning algorithms.The functionality of our system was verified by its successful application to the Chongqing Loujiazhuang pipeline-landslide in China.The results presented here provide guidelines for the monitoring,early warning,and prevention of pipeline geological hazards. 展开更多
关键词 Pipeline landslide hazards Multi parameter integrated monitor Monitoring Early warning Pipeline landslide
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Occurrence, distribution and risk assessment of antibiotics at various aquaculture stages in typical aquaculture areas surrounding the Yellow Sea 被引量:4
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作者 Jiachao Zhang Xuanrui Zhang +5 位作者 Yang Zhou Qianfan Han Xiaoli Wang Chao Song Shuguang Wang Shan Zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期621-632,共12页
The pollution of antibiotics commonly existed throughout the entire aquaculture process,but the residues of antibiotics at different aquaculture stages have rarely been studied.This study investigated the occurrence,d... The pollution of antibiotics commonly existed throughout the entire aquaculture process,but the residues of antibiotics at different aquaculture stages have rarely been studied.This study investigated the occurrence,distribution and risk assessment of antibiotics at different aquaculture stages (the non-aquaculture stage,the early aquaculture stage,the middle aquaculture stage,and the late aquaculture stage) in two typical marine aquaculture areas(Mahegang River and Dingzi Bay) surrounding the Yellow Sea.Fluoroquinolones and tetracyclines were commonly used antibiotics in the aquaculture of these areas with high detection frequencies (17%to 83%).Compared among four aquaculture stages,the highest concentration of antibiotics (9032.08 ng/L) in aquaculture ponds was detected at the late aquaculture stage.And the antibiotic pollution level of natural water was directly related to the aquaculture stages.Similarly,at the aquaculture stages,the detection frequency of antibiotics in sediments was higher than that at the non-aquaculture stage.Based on the correlation analysis,the concentration of main antibiotics in water showed a positive correlation with total nitrogen (p<0.05) and chlorophyll a (p<0.01),while it showed a negative correlation with salinity (p<0.01) in coastal water of the Dingzi Bay.According to the risk assessment,with the development of aquaculture stages,the selection pressure of fluoroquinolones and tetracyclines on resistant bacteria had increased.And the ecological risks caused by sulfonamides and tetracyclines to aquatic organisms had also increased markedly.Overall,this study may provide a reference for formulating regulatory policies regarding antibiotic use at different aquaculture stages. 展开更多
关键词 ANTIBIOTICS Aquaculture stages Correlation analysis Risk assessment
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Covalent organic nanospheres as a fiber coating for solid-phase microextraction of genotoxic impurities followed by analysis using GC-MS 被引量:2
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作者 Yanfang Zhao Jingkun Li +2 位作者 Hanyi Xie Huijuan Li Xiangfeng Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第4期583-589,共7页
Covalent organic nanospheres(CONs)were explored as a fiber coating for solid-phase microextraction of genotoxic impurities(GTIs)from active ingredients(AIs).CONs were synthesized by an easy solutionphase procedure at... Covalent organic nanospheres(CONs)were explored as a fiber coating for solid-phase microextraction of genotoxic impurities(GTIs)from active ingredients(AIs).CONs were synthesized by an easy solutionphase procedure at 25℃.The obtained nanospheres exhibited a high specific surface area,good thermostability,high acid and alkali resistance,and favorable crystallinity and porosity.Two types of GTIs,alkyl halides(1-iodooctane,1-chlorobenzene,1-bromododecane,1,2-dichlorobenzene,1-bromooctane,1-chlorohexane,and 1,8-dibromooctane)and sulfonate esters(methyl p-toluenesulfonate and ethyl ptoluenesulfonate),were chosen as target molecules for assessing the performance of the coating.The prepared coating achieved high enhancement factors(5097-9799)for the selected GTIs.The strong affinity between CONs and GTIs was tentatively attributed to π-π and hydrophobicity interactions,large surface area of the CONs,and size-matching of the materials.Combined with gas chromatography-mass spectrometry(GC-MS),the established analytical method detected the GTIs in capecitabine and imatinib mesylate samples over a wide linear range(0.2-200 ng/g)with a low detection limit(0.04-2.0 ng/g),satisfactory recovery(80.03%-109.5%),and high repeatability(6.20%-14.8%)and reproducibility(6.20%-14.1%).Therefore,the CON-coated fibers are promising alternatives for the sensitive detection of GTIs in AI samples. 展开更多
关键词 Covalent organic nanospheres Solid-phase microextraction Genotoxic impurities Gas chromatography-mass spectrometry
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Solvothermal Synthesis of ZnIn2S4 by Alcohol Solvents and Visible Light Photocatalytic Activity on Selective Oxidation and Dye Degradation 被引量:2
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作者 何运慧 陈志鑫 +2 位作者 许静静 吴艳 肖光参 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期753-762,共10页
A series of hexagonal ZnIn2S4 samples with different morphologies have been successfully prepared via a facile solvothermal approach using different alcohol solvents with the optimum synthesis time and temperature. X-... A series of hexagonal ZnIn2S4 samples with different morphologies have been successfully prepared via a facile solvothermal approach using different alcohol solvents with the optimum synthesis time and temperature. X-ray diffraction, field emission scanning electron microscopy, UV-vis diffuse reflection spectroscopy and photoelectrochemical measurements are employed to determine the properties of the samples. It is found that the solvent has a significant influence on the morphology, optical properties and electronic nature of the samples. The photocatalytic activities of the samples have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde to benzaldehyde and the degradation of methyl orange(MO) under visible light irradiation. The results reveal that the photocatalytic activities of ZnIn2S4 are closely related to the reaction solvent. The ethanol-mediated ZnIn2S4 exhibits the best photocatalytic performance toward selective oxidation of benzyl alcohol to benzaldehyde and the degradation of dye MO compared to the samples prepared in other solvents, which can be attributed to the integrative effect of the enhanced light absorption intensity and the prolonged lifetime of photogenerated carriers. In addition, a possible mechanism is proposed and discussed. It is expected that our current research could promote further interest on the synthesizing efficient ternary chalcogenides semiconducting materials for environment remediation and organic transformation. 展开更多
关键词 PHOTOCATALYST SOLVOTHERMAL selective oxidation methyl orange visible light
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Catalytic Oxidative Properties and Characterization of CuO/CeO_2 Catalysts 被引量:1
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作者 蒋晓原 周仁贤 +2 位作者 袁骏 吕光烈 郑小明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第1期55-59,共5页
The oxidative properties and characterization of CuO, CeO 2 and CuO/CeO 2 cata lysts were examined by means of a CO micro-reactor GC system, TPR, XPS and X-r ay diffraction Rietveld methods. The results show that ei... The oxidative properties and characterization of CuO, CeO 2 and CuO/CeO 2 cata lysts were examined by means of a CO micro-reactor GC system, TPR, XPS and X-r ay diffraction Rietveld methods. The results show that either CuO or CeO 2 ac tivity is quite low for CO oxidation. However, when CuO and CeO 2 are mixed, the oxidative activity of the catalyst increases significantly, probably owing to the valency status of copper species (Cu 2+ and Cu+) on the CeO 2 surfa ce, the dispersion and reducibility. XPS surface analysis shows that CuO loading is very important in forming of either Cu 2+ or Cu+. Rietveld analysis s hows that some CuO, which has smaller ion radius than Ce 4+, enters the Ce O 2 lattice after CuO and CeO 2 are mixed. When the CuO loading reaches 5.0%, the size of CuO crystals is a minimum (6.1 nm) and the micro-strain value i s a maximum (2.86×10 -3), resulting in high surface energy and the best ac tivity for CO oxidation. 展开更多
关键词 physical chemistry CuO/CeO 2 catalysts CO micro-reactor GC system rare earths
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Determination of Sparfloxacin in Human Urine by Reversed-Phase High Performance Liquid Chromatography With Nitrous Acid and Hydroiodic Pre-Column Derivatization 被引量:1
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作者 Li Ming DU Zhe Feng FAN +1 位作者 Jin Li QIAO Jing Ping WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期1007-1010,共4页
Sparfloxacin can be oxidized by nitrous acid, then react with hydroiodic acid to form a fluorescent derivative. Based on this, a reversed-phase high performance liquid chromatographic pre-column derivatization new met... Sparfloxacin can be oxidized by nitrous acid, then react with hydroiodic acid to form a fluorescent derivative. Based on this, a reversed-phase high performance liquid chromatographic pre-column derivatization new method is described for the determination of sparfloxacin in human urine. The linear range is 0.05 mg/L to 4.0 mg/L, the recoveries are 91.5%similar to 95.7% and the RSD is 1.2%similar to4.2%. The results showed that this method is suitable for the determination of sparfloxacin in human urine. 展开更多
关键词 SPARFLOXACIN HPLC pre-column derivatization human urine
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Effect of rolling deformation on microstructure and texture of spray-deposited magnesium alloy containing Mg-Nd-Zn typed LPSO 被引量:3
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作者 Zhenliang Li Fei Liu +3 位作者 Aiping Yuan Baoyu Duan Yiming Li Xiaowei Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第7期630-636,共7页
Billets of Mg-9Al-3Zn-1Mn-6Ca-2Nd alloy were produced by spray-deposition(the Osprey process).Effect of rolling deformation(T = 350?C, ε = 5%, 10%, and 15%, respectively) on microstructure and texture evolution ... Billets of Mg-9Al-3Zn-1Mn-6Ca-2Nd alloy were produced by spray-deposition(the Osprey process).Effect of rolling deformation(T = 350?C, ε = 5%, 10%, and 15%, respectively) on microstructure and texture evolution of the Mg-9Al-3Zn-1Mn-6Ca-2Nd alloy was investigated by scanning electron microscopy(SEM), transmission electron microscopy(TEM) and X-ray diffraction(XRD). Results show that at pass reduction of ε = 5%, 10% and 15% at 350?C respectively, Mg-Nd-Zn typed 24R-LPSO structure was formed in(Ca, Nd)Al2phase(C15 Laves phase). With the increase in pass reduction(i.e. 5%, 10% and 15%), the texture pole density level of basal texture(0002) changed little and pyramidal texture(10 1ˉ3) were increased.In contrast, those of prismatic texture {101ˉ0} 〈11 2ˉ0〉 were increased initially and followed by a reduction, indicating texture randomization in the grain-refined Mg alloy. The combined contribution of LPSO phase and C15 phase was key to randomize the texture of the grain-refined Mg alloy. It was noted that the microcosmic plastic deformation of LPSO phase and nanometer-sized dispersed C15 phase impeded dislocation movement, led to dislocation tangles, and facilitated recrystallization. 展开更多
关键词 Mg alloy Sub-cells Texture randomization LPSO phase Microcosmic plastic deformation
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Long-range atmospheric transport and alpine condensation of short-chain chlorinated paraffins on the southeastern Tibetan Plateau 被引量:1
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作者 Huijuan Li Duo Bu +7 位作者 Yan Gao Nali Zhu Jing Wu Xiangfeng Chen Jianjie Fu Yawei Wang Aiqian Zhang Guibin Jiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第1期275-280,共6页
Pristine alpine regions are ideal regions for investigating the long-range atmospheric transport and cold trapping effects of short chain chlorinated paraffins(SCCPs).The concentrations and alpine condensation of SCCP... Pristine alpine regions are ideal regions for investigating the long-range atmospheric transport and cold trapping effects of short chain chlorinated paraffins(SCCPs).The concentrations and alpine condensation of SCCPs were investigated in lichen samples collected from the southeastern Tibetan Plateau.The concentrations of SCCPs ranged from 3098 to 6999 ng/g lipid weight(lw)and appeared to have an increasing trend with altitude.For congeners,C10 dominated among all the congener groups.The different environmental behavior for different congener groups was closely related to their octanol-air partition coefficient(Koa).C10 congeners showed an increasing trend with altitude,whereas C13 congeners were negatively correlated with altitude.Volumetric bioconcentration factors(BCF)of SCCPs reached 8.71 in lichens,which were higher than other semivolatile organic compounds(SVOCs)such as organochlorine pesticides(OCPs),polybrominated diphenyl ethers(PBDEs),polychlorinated biphenyls(PCBs),and hexabromocyclododecane(HBCD).These results suggested that SCCPs were prone to accumulate in the lichen from the air and provided evidence for the role of lichens as a suitable atmospheric indicator in the Tibetan Plateau. 展开更多
关键词 Short-chain chlorinated paraffins Long-range atmospheric transport Alpine condensation Lichen-air accumulation
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Integrated spatial metabolomics and transcriptomics decipher the hepatoprotection mechanisms of wedelolactone and demethylwedelolactone on non-alcoholic fatty liver disease 被引量:1
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作者 Panpan Chen Zihan Zhu +8 位作者 Haoyuan Geng Xiaoqing Cui Yuhao Han Lei Wang Yaqi Zhang Heng Lu Xiao Wang Yun Zhang Chenglong Sun 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期552-561,共10页
Eclipta prostrata L.has been used in traditional medicine and known for its liver-protective properties for centuries.Wedelolactone(WEL)and demethylwedelolactone(DWEL)are the major coumarins found in E.prostrata L.How... Eclipta prostrata L.has been used in traditional medicine and known for its liver-protective properties for centuries.Wedelolactone(WEL)and demethylwedelolactone(DWEL)are the major coumarins found in E.prostrata L.However,the comprehensive characterization of these two compounds on non-alcoholic fatty liver disease(NAFLD)still remains to be explored.Utilizing a well-established zebrafish model of thioacetamide(TAA)-induced liver injury,the present study sought to investigate the impacts and mechanisms of WEL and DWEL on NAFLD through integrative spatial metabolomics with liver-specific transcriptomics analysis.Our results showed that WEL and DWEL significantly improved liver function and reduced the accumulation of fat in the liver.The biodistributions and metabolism of these two compounds in whole-body zebrafish were successfully mapped,and the discriminatory endogenous metabolites reversely regulated by WEL and DWEL treatments were also characterized.Based on spatial metabolomics and transcriptomics,we identified that steroid biosynthesis and fatty acid metabolism are mainly involved in the hepatoprotective effects of WEL instead of DWEL.Our study unveils the distinct mechanism of WEL and DWEL in ameliorating NAFLD,and presents a“multi-omics”platform of spatial metabolomics and liver-specific transcriptomics to develop highly effective compounds for further improved therapy. 展开更多
关键词 Spatial metabolomics TRANSCRIPTOMICS Non-alcoholic fatty liver disease Wedelolactone Demethylwedelolactone
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Chemical constituents of Hainan Syzygium myrsinifolium(Hance)Merr.et Perry based on ultra-high performance liquid chromatography-time-of-flight tandem mass spectrometry 被引量:1
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作者 Chaohai Pang Yuan Xu +4 位作者 Xionghui Ma Yuwei Wu Shuhuai Li Pingping Li Zhenshan Zhang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2022年第7期507-516,共10页
Syzygium myrsinifolium(Hance)Merr.et Perry is a unique plant resource on Hainan Island,and there are few reports on its chemical constituents.In the present study,we identified the major chemical constituents in the l... Syzygium myrsinifolium(Hance)Merr.et Perry is a unique plant resource on Hainan Island,and there are few reports on its chemical constituents.In the present study,we identified the major chemical constituents in the leaves of Syzygium myrsinifolium(Hance)Merr.et Perry using ultra-high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS).The chemical constituents in Syzygium myrsinifolium(Hance)Merr.et Perry were identified rapidly based on the accurate relative molecular mass and combined with literature data and reference substances.A total of 20 compounds,including organic acids,phenolic acids,and flavonoids,were identified.Among these 20 compounds,four organic acids,eight phenolic acids,seven flavonoids,and one coumarin were reported from the leaves of Syzygium myrsinifolium(Hance)Merr.et Perry for the first time.The established method was rapid and accurate,and some chemical constituents in the leaves of Syzygium myrsinifolium(Hance)Merr.et Perry have been identified.This research provided an experimental reference for the study of the constituents and utilization of Syzygium myrsinifolium(Hance)Merr.et Perry. 展开更多
关键词 Syzygium myrsinifolium(Hance)Merr.et Perry UPLC-Q-TOF-MS/MS Identification
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Rhizoma polygonati from Mount Tai:nutritional value and usefulness as a traditional Chinese medicine,source of herbzyme,and potential remediating agent for COVID-19 and chronic and hidden hunger 被引量:7
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作者 Lazzat Nurtay Qinglei Sun +7 位作者 Chenglin Mu Zhongshan Cao Qian Wang Zongsuo Liang Cuiping Ma Xugang Li Amr Amin Yingqiu Xie 《Acupuncture and Herbal Medicine》 2021年第1期31-38,共8页
Recently,traditional Chinese medicine-based treatment has succeeded in fighting coronavirus disease 2019(COVID-19),and Rhizoma polygonati(Huangjing)has been one of the recommended components.Its processed products pla... Recently,traditional Chinese medicine-based treatment has succeeded in fighting coronavirus disease 2019(COVID-19),and Rhizoma polygonati(Huangjing)has been one of the recommended components.Its processed products play antidiabetic,antiviral,antitumor,antioxidation,antifatigue,antiaging,and immune enhancement roles.The climate in Mount Tai is mild,and the dense forest is suitable for the growth of Rhizome polygonati,which has gradually evolved into a unique specie.Considering the important medicinal value and pleasant taste of Mount Tai-Rhizoma polygonati,various healthy and functional food products,controlled by quality markers with anti-COVID-19 potential,as well as emergency foods can be developed.The study aimed to review current evidence on the nutritional value of Rhizoma polygonati from Mount Tai and its usefulness as a traditional Chinese medicine,source of herbzyme,and potential remediating agent for COVID-19 and food shortage.Most recent findings regarding herbal nanomedicine have revealed that nanoscale chemical compounds are potentially efficient in drug delivery or nanozyme catalysis upon bioprocessing.Nanoflower structure is found in processed Rhizoma polygonati by self-assembly and has wide application in enzymatic events,particularly nanoscale herbzyme.The novel findings regarding Mount Tai-Rhizoma polygonati could enhance its novel applications in chronic and hidden hunger,clinical nanomedicine,and as an anti-COVID-19 agent. 展开更多
关键词 Chemical composition Coronavirus disease 2019 PHARMACOLOGY Rhizome polygonati
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Separation and Purification of Acetophenones from Cynanchum bengei Decne Root Bark by Combination of Silica Gel and High-speed Counter-current Chromatography 被引量:1
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作者 Huaizhi LI Lingchuan XU +4 位作者 Xiao WANG Qian LIU Jia LI Peng YANG Bingtian YANG 《Medicinal Plant》 2017年第2期8-11,共4页
[Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The ... [Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The crude extract of Cynanchum bengei Decne root bark was separated by silica gel column chromatography,and parts A and B containing acetophenones were obtained. Then,parts A and B were separated by HSCCC with a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water( 4∶ 6∶ 4. 5∶ 5. 5 and4∶ 6 ∶ 3 ∶ 7, V/V), respectively. [Results] From 260 mg of part A, four compounds with p-dihydroxybenzene 3. 9 mg(Ⅰ),4-hydroxyacetophenone 17. 1 mg( Ⅱ),2,5-di-hydroxyacetophenone 13. 3 mg(Ⅲ) and 2,4-dihydroxyaceto-phenone 21. 0 mg(Ⅳ) were obtained. And from 300 mg of part B,136 mg of Radix Cynanchi Bungei benzophenone(Ⅴ) was obtained. The purity of compounds determined by HPLC was 97. 0%,96. 6%,99. 2%,99. 7%,99. 5%,respectively. [Conclusions] The established method is simple and efficient. It can be used for separation of acetophenones from Cynanchum bengei Decne root bark and has better practical value,which could provide a reference basis for development and utilization of Cynanchum bengei Decne root bark. 展开更多
关键词 Silica GEL column CHROMATOGRAPHY High-speed COUNTER-CURRENT chromatography(HSCCC) Acetophenones CYNANCHUM bengei Decne root BARK
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Efficient One-pot Synthesis of Pyrrolo[2,1-a]isoquinoline and Pyrrolo[1,2-a]quinoline Derivatives
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作者 LIU Zhen-ming WU Lei +1 位作者 SUN Jing YAN Chao-guo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第6期990-993,共4页
A one-pot sequential reaction for efficient synthesis of pyrrolo[2,1-a]isoquinoline and pyrrolo[1,2-a]quinoline derivatives has been developed.The reaction included firstly the Cu-catalyzed three-component reaction of... A one-pot sequential reaction for efficient synthesis of pyrrolo[2,1-a]isoquinoline and pyrrolo[1,2-a]quinoline derivatives has been developed.The reaction included firstly the Cu-catalyzed three-component reaction of isoquinoline(quinoline),acetylenedicarboxylate and alkynylbenzene and then Cs 2 CO 3-promoted intramolecular cyclization reaction of initially formed 1-alkenyl-2-alkynyl-1,2-dihydroisoquinoline(1,2-dihydroquinoline). 展开更多
关键词 INDOLIZINE Pyrrolo[2 1-a]isoquinoline One-pot reaction Three-component reaction
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