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Compatibility of cold herb CP and hot herb AZ in Huanglian Ganjiang decoction alleviates colitis mice through M1/M2 macrophage polarization balance via PDK4-mediated glucose metabolism reprogramming
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作者 Yanyang Li Chang Liu +6 位作者 Yi Wang Peiqi Chen Shihua Xu Yequn Wu Lingzhi Ren Yang Yu Lei Yang 《Chinese Journal of Natural Medicines》 2025年第10期1183-1194,共12页
Ulcerative colitis(UC)is a chronic and non-specific inflammatory bowel disease(IBD).Huanglian Ganjiang decoction(HGD),derived from ancient book Beiji Qianjin Yao Fang,has demonstrated efficacy in treating UC patients ... Ulcerative colitis(UC)is a chronic and non-specific inflammatory bowel disease(IBD).Huanglian Ganjiang decoction(HGD),derived from ancient book Beiji Qianjin Yao Fang,has demonstrated efficacy in treating UC patients traditionally.Previous research established that the compatibility of cold herb Coptidis Rhizoma+Phellodendri Chinensis Cortex(CP)and hot herb Angelicae Sinensis Radix+Zingiberis Rhizoma(AZ)in HGD synergistically improved colitis mice.This study investigated the compatibility mechanisms through which CP and AZ regulated inflammatory balance in colitis mice.The experimental colitis model was established by administering 3%dextran sulphate sodium(DSS)to mice for 7 days,followed by CP,AZ and CPAZ treatment for an additional 7 days.M1/M2 macrophage polarization levels,glucose metabolites levels and pyruvate dehydrogenase kinase 4(PDK4)expression were analyzed using flow cytometry,Western blot,immunofluorescence and targeted glucose metabolomics.The findings indicated that CP inhibited M1 macrophage polarization,decreased inflammatory metabolites associated with tricarboxylic acid(TCA)cycle,and suppressed PDK4 expression and pyruvate dehydrogenase(PDH)(Ser-293)phosphorylation level.AZ enhanced M2 macrophage polarization,increased lactate axis metabolite lactate levels,and upregulated PDK4 expression and PDH(Ser-293)phosphorylation level.TCA cycle blocker AG-221 and adeno-associated virus(AAV)-PDK4 partially negated CP’s inhibition of M1 macrophage polarization.Lactate axis antagonist oxamate and PDK4 inhibitor dichloroacetate(DCA)partially reduced AZ’s activation of M2 macrophage polarization.In conclusion,the compatibility of CP and AZ synergistically alleviated colitis in mice through M1/M2 macrophage polarization balance via PDK4-mediated glucose metabolism reprogramming.Specifically,CP reduced M1 macrophage polarization by restoration of TCA cycle via PDK4 inhibition,while AZ increased M2 macrophage polarization through activation of PDK4/lactate axis. 展开更多
关键词 Compatibility COLITIS Cold herb Hot herb Huanglian Ganjiang decoction M1/M2 macrophage polarization PDK4 Glucose metabolism reprogramming
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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H_(2)O_(2) synthesis coupled with biomass valorization
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作者 Jiaye Li Shuang Pan +1 位作者 Yihuang Chen Qiong Liu 《Journal of Energy Chemistry》 2025年第1期215-225,共11页
Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating ... Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization. 展开更多
关键词 Atomic economy Radical pathway regulation Photocatalytic H_(2)O_(2)synthesis Rubidium atom coordination Biomass valorization
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Phase formation mechanism of Cr_(2)AlC MAX phase coating:In-situ TEM characterization and atomic-scale calculations
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作者 Guanshui Ma Haichen Wu +6 位作者 Zhi Fang Xiaohui Zhou Rende Chen Wei Yang Jiayue Zhang Zhenyu Wang Aiying Wang 《Journal of Materials Science & Technology》 2025年第3期176-184,共9页
Cr_(2)AlC,a representative MAX phase,gains increasing attention for the excellent oxidation tolerance and corrosion resistance used in harsh high temperature and strong radiation environments.However,the lack of the p... Cr_(2)AlC,a representative MAX phase,gains increasing attention for the excellent oxidation tolerance and corrosion resistance used in harsh high temperature and strong radiation environments.However,the lack of the phase formation mechanism has become the key bottleneck to the practical applications for Cr_(2)AlC synthesis with high purity at low temperatures.In this work,we fabricated the amorphous Cr-Al-C coating by a hybrid magnetron sputtering/cathodic arc deposition technique,in which the in-situ heating transmission electron microscopy(TEM)was conducted in a temperature range of 25-650℃ to address the real-time phase transformation for Cr_(2)AlC coating.The results demonstrated that increas-ing the temperature from 25 to 370℃ led to the structural transformation from amorphous Cr-Al-C to the crystalline Cr_(2)Al interphases.However,the high-purity Cr_(2)AlC MAX phase was distinctly formed at 500℃,accompanied by the diminished amorphous feature.With the further increase of temperature to 650℃,the decomposition of Cr_(2)AlC to Cr_(7)C_(3)impurities was observed.Similar phase evolution was also evidenced by the Ab-initio molecular dynamics calculations,where the bond energy of Cr-Cr,Cr-Al,and Cr-C played the key role in the formed crystalline stability during the heating process.The observa-tions not only provide fundamental insight into the phase formation mechanism for high-purity Cr_(2)AlC coatings but also offer a promising strategy to manipulate the advanced MAX phase materials with high tolerance to high-temperature oxidation and heavy ion radiations. 展开更多
关键词 Cr_(2)AlC MAX phases In-situ heating transmission electron microscopy Phase formation Bond energy
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Pressure-induced metallization and Lifshitz transition in quasi-one-dimensional TiSe_(3)single crystal
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作者 Zhenhai Yu Yunguan Ye +14 位作者 Pengtao Yang Yiming Wang Liucheng Chen Chenglin Li Jian Yuan Ziyi Liu Zhiwei Shen Shaojie Wang Mingtao Li Chaoyang Chu Xia Wang Jun Li Lin Wang Wenge Yang Yanfeng Guo 《Chinese Physics B》 2025年第8期314-322,共9页
The transition metal trichalcogenides(TMTs)with quasi-one-dimensional(quasi-1D)layered crystal structure represent a unique platform to explore intriguing physical properties.Herein,we report the successful growth of ... The transition metal trichalcogenides(TMTs)with quasi-one-dimensional(quasi-1D)layered crystal structure represent a unique platform to explore intriguing physical properties.Herein,we report the successful growth of a new TMT TiSe_(3)single crystal by using a high-pressure and high-temperature technique.The crystal structure of TiSe_(3)was determined by measuring the single-crystal x-ray diffraction and selected area electron diffraction.The 1D chain-like structure along the b-axis is formed by the TiSe_(6)prisms which share their tops and bottoms with each other.TiSe_(3)is a narrow band gap semiconductor with electron-type carriers under ambient conditions identified by the electrical and Hall effect measurements.It exhibits a pressure-induced semiconductor-to-metal transition around 4 GPa.As the pressure further increases to~6 GPa,a pressure-induced Lifshitz transition occurs,as indicated by the electrical transport measurements,high-pressure crystal structure characterizations,and electronic band structure calculations. 展开更多
关键词 high-pressure synthesis transition metal trichalcogenides quasi-one-dimensional layered crystal structure Lifshitz transition
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An Analytical Expression of Magic Angle Spinning Nuclear Magnetic Resonance Free Induction Decay in Two-Site Exchange Problem 被引量:1
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作者 SHEN Yi-min KAJI Hironori HORII Fumitaka 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第6期453-454,共2页
An analytical expression of free induction decay has been derived for calculating the magic angle spinning sideband patterns of nuclear magnetic resonance spectra in a two-site exchange problem.The expression has been... An analytical expression of free induction decay has been derived for calculating the magic angle spinning sideband patterns of nuclear magnetic resonance spectra in a two-site exchange problem.The expression has been confirmed by comparing the calculated spinning sideband patterns for powdered crystalline dimethyl sulfone at different exchange rates with experimentally measured spectra at various temperatures. 展开更多
关键词 EXCHANGE SPECTRA CRYSTALLINE
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Automatic analytical approach for the determination of 12 illicit drugs and nicotine metabolites in wastewater using on-line SPE-UHPLC-MS/MS 被引量:8
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作者 Jingyuan Wang Likai Qia +8 位作者 Chenzhi Hou Tingting Zhang Mengyi Chen Haitao Meng Mengxiang Su Hui Xu Zhendong Hua Youmei Wang Bin Di 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第6期739-745,共7页
In this study,we developed a novel on-line solid phase extraction(SPE)-ultra-high-performance liquid chromatography tandem mass spectrometry(UHPLC-MS/MS)-based analytical method for simultaneously quantifying 12 illic... In this study,we developed a novel on-line solid phase extraction(SPE)-ultra-high-performance liquid chromatography tandem mass spectrometry(UHPLC-MS/MS)-based analytical method for simultaneously quantifying 12 illicit drugs and metabolites(methamphetamine,amphetamine,morphine,codeine,6-monoacetylmorphine,benzoylecgonine,3,4-methylenedioxymethamphetamine,3,4-methylenedioxyamphetamine,cocaine,ketamine,norketamine,and methcathinone)and cotinine(COT)in wastewater samples.The analysis was performed by loading 2 m L of the sample onto an Oasis hydrophilic-lipophilic balance cartridge and using a cleanup step(5%methanol)to eliminate interference with a total run time of 13 min.The isotope-labeled internal standard method was used to quantify the target substances and correct for unavoidable losses and matrix effects during the on-line SPE process.Typical analytical characteristics used for method validation were sensitivity,linearity,precision,repeatability,recovery,and matrix effects.The limit of detection(LOD)and limit of quantification(LOQ)of each target were set at 0.20 ng/L and 0.50 ng/L,respectively.The linearity was between 0.5 ng/L and250 ng/L,except for that of COT.The intra-and inter-day precisions were<10.45%and 25.64%,respectively,and the relative recovery ranged from 83.74%to 162.26%.The method was used to analyze various wastewater samples from 33 cities in China,and the results were compared with the experimental results of identical samples analyzed using off-line SPE.The difference rate was between 19.91%and-20.44%,and the error range could be considered acceptable.These findings showed that on-line SPE is a suitable alternative to off-line SPE for the analysis of illicit drugs in samples. 展开更多
关键词 Illicit drugs and metabolites Wastewater analysis On-line solid phase extraction Ultra-high-performance liquid CHROMATOGRAPHY Mass spectrometry
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Regulating^(*)COOH intermediate via amino alkylation engineering for exceptionally effective photocatalytic CO_(2) reduction 被引量:2
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作者 Chengcheng Chen Qiaoyu Zhang +3 位作者 Fangting Liu Zhengguo Zhang Qiong Liu Xiaoming Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期282-291,共10页
Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate ... Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate and retarded desorption of target products.Engineering the interface microenvironment of catalysts has been proposed as a strategy to exert a significant influence on reaction outcomes,yet it remains a significant challenge.In this study,amino alkylation was successfully integrated into the melem unit of polymeric carbon nitrides(PCN),which could efficiently drive the photocatalytic CO_(2) reduction.Experimental characterization and theoretical calculations revealed that the introduction of amino alkylation lowers the energy barrier for CO_(2) reduction into^(*)COOH intermediate,transforming the adsorption of^(*)COOH intermediate from the endothermic to an exothermic process.Notably,the as-prepared materials demonstrated outstanding performance in photocatalytic CO_(2) reduction,yielding CO_(2)at a rate of 152.8μmol h^(-1) with a high selectivity of 95.4%and a quantum efficiency of 6.6%. 展开更多
关键词 Polymeric carbonnitride Regulate intermediate Photocatalytic CO_(2)reduction Amino alkylation ^(*)COOH adsorption
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Three-dimensional heterogeneous electro-Fenton system with reduced graphene oxide based particle electrode for Acyclovir removal 被引量:1
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作者 Nan Cai Ge Bai +4 位作者 Ting Zhang Yongqian Lei Pengran Guo Zhiliang Chen Jingwei Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期424-430,共7页
New pollutant pharmaceutical and personal care products(PPCPs),especially antiviral drugs,have received increasing attention not only due to their increase in usage after the outbreak of COVID-19 epidemics but also du... New pollutant pharmaceutical and personal care products(PPCPs),especially antiviral drugs,have received increasing attention not only due to their increase in usage after the outbreak of COVID-19 epidemics but also due to their adverse impacts on water ecological environment.Electro-Fenton technology is an effective method to remove PPCPs from water.Novel particle electrodes(MMT/rGO/Fe_(3)O_(4))were synthesized by depositing Fe3O4 nanoparticles on reduced graphene oxide modified montmorillonite and acted as catalysts to promote oxidation performance in a three-dimensional electro-Fenton(3D-EF)system.The electrodes combined the catalytic property of Fe3O4,hydrophilicity of montmorillonite and electrical conductivity of graphene oxides,and applied for the degradation of Acyclovir(ACV)with high efficiency and ease of operation.At optimal condition,the degradation rate of ACV reached 100%within 120 min,and the applicable pH range could be 3 to 11 in the 3D-EF system.The stability and reusability of MMT/rGO/Fe_(3)O_(4)particle electrodes were also studied,the removal rate of ACV remained at 92%after 10 cycles,which was just slightly lower than that of the first cycle.Potential degradation mechanisms were also proposed by methanol quenching tests and FT-ICR-MS. 展开更多
关键词 Advanced oxidation Three-dimensional electro-Fenton Reduced graphene oxide Acyclovir(ACV) Degradation
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Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(17)-type magnet
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作者 Zhuang Liu Hai-Chen Wu +5 位作者 Chao-Yue Zhang Chao-Qun Zhu Guo-Xin Chen Huan-Ming Lu Ren-Jie Chen Aru Yan 《Rare Metals》 SCIE EI CAS CSCD 2024年第4期1724-1735,共12页
Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvemen... Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvement of magnetic energy product.In this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary phase.Long strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering treatment.After solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H(TbCu_(7)-type structure)phase between the separated strip-like ordered micro-domains.This disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the length.Furthermore,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is proposed.Antiphase boundaries enriched in Cu have already existed in the precursor with long strip-like ordered micro-domains.Therefore,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(17)-type magnet.Our results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm_(2)Co_(17)-type magnets. 展开更多
关键词 Sm_(2)Co_(17) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure
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Study of HCP→FCC phase transformation mechanism under different hot compression rates of AZ31 magnesium alloy
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作者 Chun Xue Tingzhuang Han +3 位作者 Bo Gao Qianhua Yang Zhibing Chu Leifeng Tuo 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3685-3697,共13页
At present,there are few studies on the phase transition during the thermocompression plastic deformation of magnesium alloy.In this study,the evolution model of thermal compression plastic of AZ31 magnesium alloy was... At present,there are few studies on the phase transition during the thermocompression plastic deformation of magnesium alloy.In this study,the evolution model of thermal compression plastic of AZ31 magnesium alloy was constructed by molecular dynamics,and the phase transition relationship between HCP and FCC at different thermal compression rates was studied.By combining GLEEBLE thermal compression experiment with transmission electron microscopy experiment,high-resolution transmission electron microscopy images were taken to analyze the transition rules between HCP and FCC during plastic deformation at different thermal compression rates,and the accuracy of molecular dynamics analysis was verified.It is found that the slip of Shockley’s incomplete dislocation produces obvious HCP→FCC phase transition at low strain rate and base plane dislocation at high strain rate,which makes the amorphous phase transition of HCP→OTHER more obvious,which provides theoretical guidance for the formulation of forming mechanism and preparation process of magnesium alloy. 展开更多
关键词 AZ31 magnesium alloy Compression ratio Phase transition MD simulation TEM analysis
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The flavonoids from Pentorum chinense Pursh.mediates ferroptosis to alleviate sorafenib-induced liver injury in BRL-3A cells
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作者 Di Yang Bo-Wen Zhang +6 位作者 Shan Lei Jin-Tao Li Mei-Hao Peng Jia-Qing Liao Xue Tang Qi Zhao Qiu-Xia Lu 《Traditional Medicine Research》 2024年第2期18-26,共9页
Background:Drug-induced liver damage is a severe medical issue that affects people all over the world.Sorafenib has some side effects that cause liver injury.A dietary medicinal plant called Penthorum chinense Pursh.(... Background:Drug-induced liver damage is a severe medical issue that affects people all over the world.Sorafenib has some side effects that cause liver injury.A dietary medicinal plant called Penthorum chinense Pursh.(PCP)has hepatoprotective properties.There are currently few reports on PCP’s protective impact and mechanism against sorafenib-induced liver injury.Methods:To create a liver injury model,sorafenib was administered to BRL-3A cells.Cell viability assays,immunofluorescence tests,Western blotting,real-time quantitative PCR,and high-content imaging systems were utilized to examine PCP’s effect and mechanism.Results:In this study,PCP treatment mitigated the liver damage caused by sorafenib by enhancing cell survival,lowering lipid reactive oxygen species and malondialdehyde levels,and elevating glutathione levels.In addition,PCP can enhance the protein expression of cystine/glutamate transporter xCT and glutathione peroxidase 4,reduce iron content and alleviate mitochondrial toxicity.Further mechanism studies revealed that PCP inhibited ferroptosis by promoting the production of nuclear factor E2-related factor 2 nuclear translocation and subsequently affecting target genes(HO-1 and NQO1).Conclusion:Together,PCP regulates the nuclear factor E2-related factor 2 pathway,which helps to lessen ferroptosis brought on by sorafenib. 展开更多
关键词 SORAFENIB Pentorum chinense Pursh. ferroptosis oxidative stress NRF2
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Bismuth-based halide double perovskite Cs_(2)KBiCl_(6): Disorder and luminescence
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作者 Pan Liu Yanming Sun +6 位作者 Alberto J.Fernández-Carrión Bowen Zhang Hui Fu Lunhua He Xing Ming Congling Yin Xiaojun Kuang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期504-508,共5页
A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron diffraction.Rather than an ordered structure,the crystal st... A new bismuth-based halide double perovskite Cs_(2)KBiCl_(6) was isolated successfully through solid-state reactions and investigated using X-ray and neutron diffraction.Rather than an ordered structure,the crystal structure consists of shifted Cs,K,Bi,and Cl sites from the ideal positions with fractional occupancy in compensation,leading to variable local coordination of Cs^(+)ions,as revealed by^(133)Cs solid-state nuclear magnetic resonance spectroscopy.Cs_(2)KBiCl_(6) displays volume hysteresis at 5-298 K range upon heating and cooling.The Cs_(2)KBiCl_(6) has a direct bandgap of 3.35(2)eV and red-shift luminescence of around 600 nm upon Mn doping compared with the Na analogue.The stabilization of disordered structure in Cs_(2)KBiCl_(6) is related to two factors including the large-sized K^(+)cation which prefers to coordinate with more than six Cl^(-),and the Bi^(3+)with 6s^(2) lone pair which has a preference for a local asymmetric environment.These findings could have general application and help to understand the structure and property of halide perovskites. 展开更多
关键词 Halide perovskite Double perovskite LUMINESCENCE Disordered structure Direct bandgap
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The hybrid Pt nanoclusters/Ru nanowires catalysts accelerating alkaline hydrogen evolution reaction
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作者 Jingjing Yan Rundong Wu +3 位作者 Guoqiang Jin Litao Jia Gang Feng Xili Tong 《Advanced Powder Materials》 2024年第5期23-32,共10页
Water electrolysis via alkaline hydrogen evolution reaction(HER)is a promising approach for large-scale production of high-purity hydrogen at a low cost,utilizing renewable and clean energy.However,the sluggish kineti... Water electrolysis via alkaline hydrogen evolution reaction(HER)is a promising approach for large-scale production of high-purity hydrogen at a low cost,utilizing renewable and clean energy.However,the sluggish kinetics derived from the high energy barrier of water dissociation impedes seriously its practical application.Herein,a series of hybrid Pt nanoclusters/Ru nanowires(Pt/Ru NWs)catalysts are demonstrated to accelerate alkaline HER.And the optimized Pt/Ru NWs(10%wt Pt)exhibits exceptional performance with an ultralow overpotential(24 mV at 10 mA cm^(-2)),a small Tafel slope(26.3 mV dec^(-1)),and long-term stability,outperforming the benchmark commercial Pt/C-JM-20%wt catalyst.This amazing performance also occurred in the alkaline anion-exchange membrane water electrolysis devices,where it delivered a cell voltage of about 1.9 V at 1 A cm^(-2)and an outstanding stability(more than 100 h).The calculations have revealed such a superior performance exhibited by Pt/Ru NWs stems from the formed heterointerfaces,which significantly reduce the energy barrier of the decisive rate step of water dissociation via cooperative-action between Pt cluster and Ru substance.This work provides valuable perspectives for designing advanced materials toward alkaline HER and beyond. 展开更多
关键词 Cooperative-action Pt nanoclusters Ru nanowires Hydrogen evolution reaction HETEROINTERFACE
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低氧预处理对低氧/复氧心肌能量代谢的作用 被引量:4
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作者 吴昌琳 林立政 +4 位作者 LU Zhi 卢智 黄永仁 庄建国 周兆年 《中国应用生理学杂志》 CAS CSCD 北大核心 2001年第1期43-46,共4页
目的 :研究低氧预处理 (HPC)对心肌的保护作用。方法 :借助31P NMR图谱技术 ,在模拟Langendorff离体灌流大鼠心脏的正常生理条件下 ,跟踪心肌高能磷酸化合物含量的动态变化。结果 :在 30min低氧期 ,PCr、ATP相对含量及PCr/Pi值逐渐减小 ... 目的 :研究低氧预处理 (HPC)对心肌的保护作用。方法 :借助31P NMR图谱技术 ,在模拟Langendorff离体灌流大鼠心脏的正常生理条件下 ,跟踪心肌高能磷酸化合物含量的动态变化。结果 :在 30min低氧期 ,PCr、ATP相对含量及PCr/Pi值逐渐减小 ,但HPC组减小的速度比对照组慢 ;而在复氧期 ,HPC组能提高心肌高能磷酸化合物含量的恢复程度 ,特别在复氧初期 ,HPC组PCr、ATP相对含量及PCr/Pi值立即有了恢复 ;在本实验中 ,HPC对pHi的改善不显著。 结论 :HPC能降低后续长时间低氧及复氧阶段的心肌能量代谢 ,对心肌的低氧 展开更多
关键词 ^31P-NMR 低氧预处理 高能磷酸化合物 大鼠心脏 低氧/复氧 心肌缺血
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用微芯片实现流动注射化学发光方法测定水样中铬(Ⅲ) 被引量:12
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作者 徐溢 Bessoth F Manz A 《分析化学》 SCIE EI CAS CSCD 北大核心 2000年第7期876-878,共3页
在微化学反应器上首次实现了流动注射 Cr(Ⅲ)-鲁米诺-H2O2化学发光反应测定,并 定量测试水样中微量Cr(Ⅲ),检出限达到 10-7 mol/L。
关键词 微芯片 流动注射 化学发光 微量分析
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微型全分析系统 被引量:8
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作者 徐溢 Jan C.T. Eijkel A.Manz 《分析化学》 SCIE EI CAS CSCD 北大核心 2000年第10期1295-1299,共5页
系统阐述了分析化学新兴研究领域微型全化学分析系统(μ-TAS)的概念和原理,并
关键词 微型全化学分析系统 微芯片 自动分析
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Twinning,phase boundary structure and development of high coercivity in Fe-rich Sm_(2)Co_(17)-type magnets 被引量:5
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作者 Haichen Wu Zhuang Liu +7 位作者 Chaoyue Zhang Qiqi Yang Huanming Lu Guoxin Chen Xinming Wang Yong Li Renjie Chen Aru Yan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第1期102-111,共10页
The microstructure of twinning as well as the phase boundary between 1:5 H and 2:17 R phase in Fe-rich Sm_(2)Co_(17)-type magnets was characterized at atomic scale using nanobeam diffraction and highresolution STEM-HA... The microstructure of twinning as well as the phase boundary between 1:5 H and 2:17 R phase in Fe-rich Sm_(2)Co_(17)-type magnets was characterized at atomic scale using nanobeam diffraction and highresolution STEM-HAADF imaging,and the reason for the dramatic increase of coercivity during slow cooling was investigated based on the microchemistry analysis.The twinning relationship in the 2:17 R phase originates from ordered substitution of Sm atoms by Co-Co atomic pairs on every three(3033)and(3033)planes,leading to formation of two corresponding equivalent twin variants.The basal plane of the 2:17 R phase,the 1:3 R platelet phase across the 2:17 R cell and the 1:5 H cell boundary phase between two adjacent 2:17 R cells all can act as effective twin boundary.The cell boundary phase is precipitated along the pyramidal habit plane,and a fully coherent phase boundary(PB)is formed between the 1:5 H and 2:17 R phases with the orientation relationship to be PB//(1121)1:5 H//(1011)_(2):17 R.The phase boundary may either be parallel to or intersect with the pyramidal planes occupied by Co-Co atomic pairs.The substantial increase of coercivity during slow cooling is ascribed to the development of large gradient of the elements concentration within the cell boundary phase,resulting in large gradient of domain wall energy,and thus the pinning strength of the cell boundary phase against magnetic domain wall motion is significantly enhanced. 展开更多
关键词 Sm_(2)Co_(17)-type magnets Microstructure TWINNING Phase boundary COERCIVITY Rare earths
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Integration of cryogenic trap to gas chromatography-sulfur chemiluminescent detection for online analysis of hydrogen gas for volatile sulfur compounds 被引量:7
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作者 Yi Pan Fan-Feng Deng +3 位作者 Zheng Fang Han-Jiao Chen Zhou Long Xian-Deng Hou 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第11期3440-3445,共6页
Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative byproducts.However,sulfur compounds(SCs)ev... Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative byproducts.However,sulfur compounds(SCs)even at trace level(nmol/mol)are usually involved in cell construction and further H_(2)production,which would cause degradation of the catalysts and shorten the lifetime of the fuel cells.Moreover,the highly reactive SCs could cause varied species and concentrations of them in complex matrices,so online rather than offline analysis of SCs in H_(2)would be preferred.In this context,we developed a new system combining online cryogenic preconcentration of nine SCs and subsequent determination by GC-SCD(sulfur chemiluminescent detector),with the correlation coefficients of the calibration curves higher than 0.999,calculated limits of detection no higher than 0.050 nmol/mol,analytical time around 30 min per sample,and satisfactory precision and accuracy(RSD<5%and SD<15%).The analytical performance was much better than or at least comparable to the previously reported and the developed system was successfully applied for real sample analysis. 展开更多
关键词 GAS-CHROMATOGRAPHY Hydrogen fuel cell Online cryogenic trap Sulfur chemiluminescent detector Volatile sulfur compounds
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Effects of Pr-Cu-Ti intergranular addition on microstructure and magnetic properties of heavy-rare-earth-free Nd-Fe-B sintered magnets 被引量:5
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作者 Jinhao Zhu Guangfei Ding +6 位作者 Bo Zheng Haichen Wu Lei Jin Zhehuan Jin Shuai Guo Renjie Chen Aru Yan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第5期778-783,I0004,共7页
By intergranular addition of Pr-Cu-Ti alloy powders in the Nd-Fe-B sintered magnets with the normal B component,we propose an approach to the optimization of grain boundary and local Nd-Fe-B composition system.The coe... By intergranular addition of Pr-Cu-Ti alloy powders in the Nd-Fe-B sintered magnets with the normal B component,we propose an approach to the optimization of grain boundary and local Nd-Fe-B composition system.The coercivity is enhanced from 1.42 to 1.86 T,while further addition leads to a reduction in remanence and coercivity.The analyses of phase composition reveal that Ti mainly exists in the form of metallic Ti alloy,and part of Ti combines with B to form the TiB2 phase after the liquid phase sintering process.This process results in a consumption of B in the local Nd-Fe-B composition system and a change of the grain boundary component,which contributes to the formation process of the RE_(6)(Fe,M)_(14) phase after the annealing process.Therefore,with the modification of grain boundary and composition system,the intergranular addition of Pr-Cu-Ti induces the generation of continuous thin grain boundary phases.It promotes the intergrain exchange decoupling,increasing the coercivity in the annealed magnet.While the excess addition results in the segregation of TiB_(2),as well as the precipitation of TiB_(2) into the Nd-Fe-B phase,which leads to structural defects.Thus,the further effort for the addition alloy with Ti to reduce the deterioration of the microstructure will lead to further improvement in magnetic properties. 展开更多
关键词 Nd-Fe-B sintered magnet Magnetic properties Grain boundary Microstructures Rare earths
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Prevalence and methodologies for detection,characterization and subtyping of Listeria monocytogenes and L.ivanovii in foods and environmental sources 被引量:7
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作者 Jin-Qiang Chena Patrick Regan +2 位作者 Pongpan Laksanalamai Stephanie Healey Zonglin Hua 《Food Science and Human Wellness》 SCIE 2017年第3期97-120,共24页
Listeria monocytogenes,one of the most important foodborne pathogens,can cause listeriosis,a lethal disease for humans.L.ivanovii,which is closely related to L.monocytogenes,is also widely distributed in nature and in... Listeria monocytogenes,one of the most important foodborne pathogens,can cause listeriosis,a lethal disease for humans.L.ivanovii,which is closely related to L.monocytogenes,is also widely distributed in nature and infects mainly warm-blooded ruminants,causing economic loss.Thus,there are high priority needs for methodologies for rapid,specific,cost-effective and accurate detection,characterization and subtyping of L.monocytogenes and L.ivanovii in foods and environmental sources.In this review,we(A)described L.monocytogenes and L.ivanovii,world-wide incidence of listeriosis,and prevalence of various L.monocytogenes strains in food and environmental sources;(B)comprehensively reviewed different types of traditional and newly developed methodologies,including culture-based,antigen/antibody-based,LOOP-mediated isothermal amplification,matrix-assisted laser desorption ionization-time of flight-mass spectrometry,DNA microarray,and genomic sequencing for detection and characterization of L.monocytogenes in foods and environmental sources;(C)comprehensively summarized different subtyping methodologies,including pulsed-field gel electrophoresis,multi-locus sequence typing,ribotyping,and phage-typing,and whole genomic sequencing etc.for subtyping of L.monocytogenes strains from food and environmental sources;and(D)described the applications of these methodologies in detection and subtyping of L.monocytogenes in foods and food processing facilities. 展开更多
关键词 Foodborne pathogens Listeria monocytogenes Listeria ivanovii Molecular characterization SUBTYPING
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