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GEOLOGY AND METALLOGENY OF PRECAMBRIAN ACTIVIZATION (PROTODIWA) IN CONCERN OF PRECAMBRIAN EARTHCRUST EVOLUTION 被引量:1
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作者 L. V. Grigorieva and N. F. Shinlarev(St. Petersburg State University , Russia) 《Geotectonica et Metallogenia》 1995年第4期39-47,共9页
The beginning of intraplate (diwa type) activization must be attributed to Early Proterozoic, When thick continental earthcrust and thermodynamic conditions close to the present had estahlished.Precambrian activizatio... The beginning of intraplate (diwa type) activization must be attributed to Early Proterozoic, When thick continental earthcrust and thermodynamic conditions close to the present had estahlished.Precambrian activization (protodiwa) induced hypogene structural recaworking, deepseated laults and troughs development, gabbro-granite and subalkaline magtnatizm, zone metamorphism, magmatogenic and hydrothermal ore production,whicll proceeded regularly, that allows their timing.Protodiwa metallogeny contrasts with the previous Precambrian due to relatively increased petrogenic and ore elements differentiation. Elements of various geochemical origins and noncharacteristic of Early Precambrian are found.ore deposition appears determined by gabbro-diorite-granite, gabbroumonzonite-syenite-granite, gabbro-anorthosite-rapakivi granite differentiated magmatic series. Elements mode is controlled both by fractional crystallization and the alliance with fluid phase.Throughout Late Proterozoic diwa geodynamics remained uniform, the most intensive on the fringe of Early Proterozoic folded belts. This allows us suggest the post-collisional subduction activating mantle and lower litosphere, and mantle diapirs formation the motive forces of protodiwa activization. 展开更多
关键词 activization DIWA EVENTS protodiwa
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METAMORPHISM AND FORMATION IN DIWA (TECTONO-PETROGENIC ACTIVIZATION) STRUCTURES
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作者 KULISH 《Geotectonica et Metallogenia》 1994年第Z2期19-21,共3页
关键词 Ta TR METAMORPHISM AND FORMATION IN DIWA STRUCTURES TECTONO-PETROGENIC activization HG Ag Pb
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Overexpression of the inwardly rectifying potassium channel Kir4.1 or Kir4.1 Tyr^(9)Asp in Müller cells exerts neuroprotective effects in an experimental glaucoma model 被引量:1
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作者 Fang Li Zhen Li +6 位作者 Shuying Li Hong Zhou Yunhui Guo Yongchen Wang Bo Lei Yanying Miao Zhongfeng Wang 《Neural Regeneration Research》 2026年第4期1628-1640,共13页
Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apopt... Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma. 展开更多
关键词 apoptosis chronic ocular hypertension glial cell activation Kir4.1 overexpression Kir4.1 Tyr^(9)Asp mutation microglia Müller cells NEUROINFLAMMATION neuroprotection retinal ganglion cells
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Pressurized physically activated carbon used as a high-performance,low cost cathode material in lithium–sulfur batteries
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作者 Minghao Wang Zhangxiao +4 位作者 Gao Hongye Hata Satoshi Nakabayashi Koji Yoon Seongho Miyawaki Jin 《新型炭材料(中英文)》 北大核心 2026年第1期127-141,共15页
Lithium–sulfur(Li–S)batteries are promisingcandidates for next-generation energy storagegiven their high energy density and potential low cost.Chemically activated carbon(CAC)is often used fortheir cathodes,because ... Lithium–sulfur(Li–S)batteries are promisingcandidates for next-generation energy storagegiven their high energy density and potential low cost.Chemically activated carbon(CAC)is often used fortheir cathodes,because it has a high specific surfacearea for sulfur loading.We have developed a pressurizedphysical activation(PPA)method that producedan activated carbon(PPAC)with a high specific surfacearea comparable to that of CAC.The pore structure of PPAC could be changed and its use as a cathode material for Li–Sbatteries was investigated.Battery tests at different capacity rates(C-rates)showed that it had a much improved high-rate performancewith a discharge capacity of 900 mAh/(g of sulfur)at 1 C,in contrast to only 600 mAh/(g of sulfur)for CAC.Porestructure analyses showed that PPAC prepared at a high activation temperature(1000℃)had unusual channel-like mesoporesbetween the microdomains that are the basic structural units of artificial carbon materials.These are connected to microporesdeveloped in each microdomain,and deliver ions from the surroundings to the internal pores and vice versa.The well-developedmicropores and mesopores of PPAC respectively ensured the high adsorption of lithium polysulfides and a high rate ofion diffusion.Compared to CAC,PPAC is a high-performance,low-cost cathode material that is promising for use in futureLi–S batteries. 展开更多
关键词 Activated carbon Pressurized physical activation Mesoporous channel Lithium-sulfur batteries MICRODOMAIN
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Research on Secondary Metabolites from a Mangrove-Derived Fungus Penicillium janthinellum XLN32122 and Their Biological Activities
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作者 Shi Jueying Qiu Yikang +6 位作者 Lan Jing Xu Zhenyang Wang Yi Li Jiaxiang Luo Youping Huang Guolei Zheng Caijuan 《有机化学》 北大核心 2026年第2期678-683,共6页
new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the... new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the mangrovederived fungus Penicillium janthinellum XLN32122.The structure of 1 was elucidated on the basis of extensive 1D and 2D NMR spectra data analysis,HR-ESI-MS,electronic circular dichroism(ECD)calculations.Trichodermamide B(3)exhibited better inhibitory effect on nitric oxide(NO)production in lipopolysaccharide(LPS)induced RAW 264.7 cells with an IC_(50)value of(13.13±0.005)μmol/L than that of the positive control dexamethasone[IC_(50)=(136.84±1.33)μmol/L].Compound 3 exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus(MRSA)with an IC_(50)value of 12.5μg/mL,while the positive control vancomycin showed an IC_(50)value of 1.563μg/mL. 展开更多
关键词 mangrove-derived fungi secondary metabolites anti-inflammatory activity antibacterial activity
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美国《保健物理》(Health Physics)杂志英文摘要(2025年129卷第6期)
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《辐射防护》 北大核心 2026年第2期170-174,共5页
Neutron Activation Dose Assessment Based on a Human Head Phantom Post-BNCT Guanchao Wu1,2, Zuokang Lin2, Zijian Zhang1,2, Zhiyuan Lin1,2, Yinan Zhu2, Ye Dai2 and Zhimin Dai2(1.ShanghaiTech University, Shanghai, 201210... Neutron Activation Dose Assessment Based on a Human Head Phantom Post-BNCT Guanchao Wu1,2, Zuokang Lin2, Zijian Zhang1,2, Zhiyuan Lin1,2, Yinan Zhu2, Ye Dai2 and Zhimin Dai2(1.ShanghaiTech University, Shanghai, 201210, China;2.Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China) 展开更多
关键词 neutron activation dose assessment dose assessment zhimin dai shanghaitech human head phantom yinan zhu ye dai zuokang lin neutron activation
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Co(Ⅱ) and Ni(Ⅱ) complexes of 3,3-diphenylpropionic acid and 2,2′-dipyridylamine: Structures and biological activities
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作者 FENG Jing WANG Renshu +1 位作者 WANG Hu LIU Hailong 《无机化学学报》 北大核心 2026年第3期617-631,共15页
Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(... Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(PAm)]·2H_(2)O(2)were determined by single-crystal X-ray diffraction,IR spectroscopy,and powder X-ray diffraction.Hirshfeld surface analysis provided quantitative insights into the intermolecular interactions within the complexes,while molecular docking studies elucidated their binding modes and affinities toward urease.Furthermore,the biological activities of both complexes were systematically evaluated through a range of assays,including DNA binding,urease inhibition,antibacterial activity,and in vitro cytotoxicity against cancer cells.Both complexes exhibited binding affinity for DNA and displayed notable urease inhibitory activity.Under in vitro conditions,both complexes showed appreciable cytotoxicity toward HepG2 cells with efficacy comparable to clinically used platinumbased anticancer agents.CCDC:2479943,1;2479944,2. 展开更多
关键词 crystal structure computational analysis urease inhibition antibacterial activity CYTOTOXICITY
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Characterization of Glutarimide Derivatives from Agrimonia pilosa-Associated Endophytic Streptomyces sp.YINM00048
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作者 Su Yuying Wang Yingfang +4 位作者 Yi Mengzhuo Zhao Lixing Li Jiaxuan Ma Ling Yin Min 《有机化学》 北大核心 2026年第1期289-294,共6页
Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 k... Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively. 展开更多
关键词 Agrimonia pilosa endophytic Streptomyces glutarimide structural elucidation anti-tumor activity
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Fe-modified MoS_(2)/NC catalyst for hydrodeoxygenation of lignin into aviation fuel-range arenes
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作者 CHEN Lu DENG Yacong +6 位作者 WU Zifan QIU Yuting YANG Xin SUI Guoyong LIU Bin YU Yingmin CHAI Yongming 《燃料化学学报(中英文)》 北大核心 2026年第4期45-57,共13页
Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a ... Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes. 展开更多
关键词 activated carbon FeMoS/NC HYDRODEOXYGENATION 4-ethylguaiacol LIGNIN aromatic hydrocarbon
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Hot Compression Deformation Behavior and Processing Maps of Mg-Zn-Mn(-Sn)-Ca Alloy
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作者 Chen Xia Zhu Yulong +2 位作者 Liu Quanyi Zhang Dingfei Pan Fusheng 《稀有金属材料与工程》 北大核心 2026年第3期627-635,共9页
The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from... The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from 0.001 s^(-1) to 1 s^(-1).The results show that the addition of Sn promotes dynamic recrystallization(DRX),and CaMgSn phases can act as nucleation sites during the compression deformation.Flow stress increases with increasing the strain rate and decreasing the temperature.Both the ZM61-0.5Ca and ZMT612-0.5Ca alloys exhibit obvious DRX characteristics.CaMgSn phases can effectively inhibit dislocation motion with the addition of Sn,thus increasing the peak fl ow stress of the alloy.The addition of Sn increases the hot deformation activation energy of the ZM61-0.5Ca alloy from 199.654 kJ/mol to 276.649 kJ/mol,thus improving the thermal stability of the alloy.For the ZMT612-0.5Ca alloy,the optimal hot deformation parameters are determined to be a deformation temperature range of 350–400℃and a strain rate range of 0.001–0.01 s^(-1). 展开更多
关键词 hot deformation constitutive equation processing map deformation activation energy magnesium alloy
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Two New Linear Furocoumarins from Notopterygium incisum and Their Anti-inflammatory Activity
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作者 Hu Su Zhao Lilian +4 位作者 Li Xinyu Ye Yubei Deng Yun Huang Lijun Guo Dale 《有机化学》 北大核心 2026年第1期300-303,共4页
Two new linear furocoumarins were isolated from Notopterygium incisum using silica gel,gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.The structures of the new compound... Two new linear furocoumarins were isolated from Notopterygium incisum using silica gel,gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.The structures of the new compounds were elucidated through analysis of spectroscopic evidence,including data obtained from high-resolution electrospray ionization mass spectrometry(HRESIMS)and nuclear magnetic resonance(NMR).The absolute configurations of Notoprenylate L(1)and Nototerprinol K(2)were further confirmed using electronic circular dichroism(ECD)calculations.Compound 1 demonstrated the ability to inhibit the expression of nitric oxide(NO),a pro-inflammatory factor,in lipopolysaccharide-induced RAW264.7 macrophages at a concentration of 7.5μmol/L,indicating its potential for anti-inflammatory activity. 展开更多
关键词 Notopterygium incisum linear furocoumarin anti-inflammatory activity
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Side-chain Engineering of“Bridging”Polymer Acceptors with Donor/Acceptor Dual Similarity for High-performance Ternary Organic Solar Cells
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作者 LIU Miaomiao FU Mengran +8 位作者 GAO Die ZHANG Wanpeng LIANG Ying HE Yuanyuan ZHAO Qiaoqiao ZHAO Tingxing LI Hongbo DING Zicheng HAN Yanchun 《高等学校化学学报》 北大核心 2026年第4期111-121,共11页
The morphology of active layer plays a critical role in determining the photovoltaic performance of organic solar cells(OSCs).However,binary blends often suffer from suboptimal phase separation,which limits the effici... The morphology of active layer plays a critical role in determining the photovoltaic performance of organic solar cells(OSCs).However,binary blends often suffer from suboptimal phase separation,which limits the efficiency of OSCs.Herein,two bridging polymer acceptors(PAs)—benzodithiophene-(2-ethylhexyl)oxy(BDT-C2C4)and benzodithiophene-octyloxy(BDT-C_(8))—are designed and synthesized by combining a benzodithiophene(BDT)unit as the donor moiety[poly({4,8-bis[5-(2-ethylhexyl)-4-fluorothiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl}){5,8-bis[4-(2-butyloctyl)thiophen-2-yl]dithieno[3',2':3,4]},D18],and a 2,2′-((2Z,2′Z)-{[12,13-Bis(2-butyloctyl)-12,13-dihydro-3,9-dinonylthieno[2,3]thieno[3,2-b]pyrrolo[4,5-g]thieno[2,3-b]indole-2,10-diyl]bis(methanylylidene)}bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(Y6)derivative as the acceptor moiety.BDT-C2C4 and BDT-C_(8) are functionalized with(2-ethylhexyl)oxy and octyloxy side chains on the BDT unit,respectively.Both PAs show complementary absorption and cascaded energy levels with the donor D18 and the acceptor 2,2′-((2Z,2′Z)-{[12,13-bis(3-ethylheptyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″∶4′,5′]thieno[2′,3′∶4,5]pyrrolo[3,2-g]thieno[2′,3′∶4,5]thieno[3,2-b]indole-2,10-diyl]bis(meth⁃aneylylidene)}bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(N3),but BDT-C_(8) exhibits better compatibility with D18 and N3 compared to BDT-C2C4.When incorporated as a third component into the D18∶N3 blend,both PAs improve the active layer morphology.In particular,the D18∶N3∶BDT-C_(8) blend shows significantly optimized morphology,featuring reduced phase separation and a fibrous network structure.As a result,the device based on D18∶N3∶BDT-C_(8) achieves a power conversion efficiency of 18.18%,significantly higher than that of the device based on D18∶N3(ca.17.37%).This work presents a compatibilizer strategy for optimizing blend morphology towards high-performance ternary OSCs. 展开更多
关键词 Organic solar cell Ternary strategy Polymer acceptor Active layer morphology
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Study on Secondary Metabolites of Marine-Derived Fungus Cladosporium sp. MDW-211
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作者 Wang Jianjian Zheng Shengyan +5 位作者 Zhang Jie Gao Wenpeng Kong Fandong Li Peihai Wang Cong Cao Shugeng 《有机化学》 北大核心 2026年第2期684-688,共5页
study was conducted on the biologically active secondary metabolites produced by the marine fungus Cladosporium sp.MDW-211.Preparative high performance liquid chromatography(HPLC)and other techniques were used to isol... study was conducted on the biologically active secondary metabolites produced by the marine fungus Cladosporium sp.MDW-211.Preparative high performance liquid chromatography(HPLC)and other techniques were used to isolate and purify the compounds,the structures of the compounds 1 were determined by high-resolution electrospray ionization mass spectrometry(HR-ESI-MS),nuclear magnetic resonance(NMR)spectroscopy,X-ray and other methods,and the pro-angiogenic activity of the compounds was evaluated by zebrafish model.One new dihydroisocoumarin 1(4'S-hydroxyasperentin)and three known dihydroisocoumarins 2~4 were obtained and identified.Bioactivity assays revealed that compound 3 exhibited pro-angiogenic activity at concentrations of 20 and 40μmol/L,which is reported here for the first time. 展开更多
关键词 marine fungus Cladosporium sp.MDW-211 DIHYDROISOCOUMARINS pro-angiogenic activity
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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The role of copper valence states in CuZnAl catalysts for CO_(2)-to-methanol conversion
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作者 QIU Zhengpu XU Yunzhao +11 位作者 WANG Peng TAO Xiaoxia ZHANG Huimin CHEN Yang LIU Yi YANG Hua CAO Fenghai FU Yajie WU Lizhi TANG Yu XU Xiaoying TAN Li 《燃料化学学报(中英文)》 北大核心 2026年第4期58-67,共10页
CuZnAl(CZA)is a classic industrial catalyst widely used for the synthesis of methanol from syngas,but its catalytic performance is not optimal for the hydrogenation of CO_(2) to methanol.Meanwhile,understanding the ca... CuZnAl(CZA)is a classic industrial catalyst widely used for the synthesis of methanol from syngas,but its catalytic performance is not optimal for the hydrogenation of CO_(2) to methanol.Meanwhile,understanding the catalytic mechanism of Cu species in the CZA catalyst remains a great challenge.In this study,we systematically investigated the valence state change of active Cu species in CZA catalyst and their influence on catalytic performance by modifying the catalysts with varying amounts of electron donor K,thus identifying the catalytic function of Cu species with different valence states.H2-TPR,XPS and HR-TEM characterizations reveal that the highly dispersed K species supported on CZA catalysts will inhibit the reduction of CuO,resulting in a small amount of Cu_(2)O active species being produced under reaction conditions thus causing a decrease in catalytic activity.Furthermore,XRD and Cu LMM spectra show that the proportion of Cu^(0) in K-modified CZA catalysts increases with K loading,but a higher proportion of Cu^(0) species on the surface obviously promotes the reverse water gas shift(RWGS)reaction.According to the results of in situ infrared spectroscopy,CZA catalyst follows the reaction pathway mediated by HCOO^(*)in the hydrogenation of CO_(2) to methanol. 展开更多
关键词 CO_(2)hydrogenation CuZnAl catalysts METHANOL active species electronic promoter
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Health Phys.Abstracts,Volume 129,Number 4
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《辐射防护》 北大核心 2026年第1期87-91,共5页
Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,... Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,and Wei-hao Qin1(1.National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing,100088,China.) 展开更多
关键词 nuclear medicine workers health physics carbon cartridge internal dose assessment analysis method I activity
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Rapid determination of DHA in sturgeon caviar extracts and its correlation with bioactive efficacy
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作者 Xiaoling Tan Jiaxin Kang 《日用化学工业(中英文)》 北大核心 2026年第3期347-353,共7页
A reversed-phase high-performance liquid chromatography(HPLC)method was developed for the direct determination of docosahexaenoic acid(DHA)in sturgeon caviar extract.The assay employed n-hexane extraction combined wit... A reversed-phase high-performance liquid chromatography(HPLC)method was developed for the direct determination of docosahexaenoic acid(DHA)in sturgeon caviar extract.The assay employed n-hexane extraction combined with gradient elution(ZORBAX SB-C18 column),with data collected using a diode array detector.The content was calculated by external standard method and validated against the national standard(GB 5009.168-2016).The study also measured DPPH free radical scavenging capacity and moisture retention rate across different DHA concentration groups.The results demonstrate that the proposed method exhibits excellent linearity(r=0.9997),with recovery rates ranging from 92.1% to 101.1% and relative standard deviations(RSD)of 2.23% to 3.92%.Compared to the national standard method,the relative deviation was 0.67% to 1.68%.At specific test concentrations,the high-DHA group shows significantly higher moisture retention(100.48%),hygroscopicity(100.85%),and DPPH scavenging efficiency(57.46%)than the low-DHA group(10.33%,11.76%,and 3.71%).The RP-HPLC method developed in this study simplifies DHA detection procedures with simple reagents and reliable results,making it suitable for rapid qualitative identification and quantitative analysis of target components in caviar extract quality control.The DPPH experiment further reveals the correlation between DHA content and antioxidant efficacy in sturgeon caviar extracts,providing scientific evidence for developing functional cosmetics. 展开更多
关键词 reverse-phase high-performance liquid chromatography DHA sturgeon roe extract moisturizing capacity antioxidant activity method validation
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Prescribed-Time Active Disturbance Rejection Control for Electromagnetic Formation Flight Under Model Uncertainties and Disturbances
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作者 SHEN Xixi MENG Bin HU Jiangping 《空间控制技术与应用(中英文)》 北大核心 2026年第1期94-102,共9页
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ... This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller. 展开更多
关键词 electromagnetic formation prescribed time active disturbance rejection control output feedback control
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Pd-catalyzed B—H bond activation and annulation of nido-carborane with terminal olefins: Facile construction of 2D-3D fused polycyclic compounds
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作者 SUN Fangxiang ZHANG Qing +6 位作者 ZHANG Yifan SUN Haoyi Akim VShmal′ko Sergey AAnufriev Igor BSivaev TU Deshuang YAN Hong 《无机化学学报》 北大核心 2026年第3期467-478,共12页
To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nido... To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d. 展开更多
关键词 CARBORANE B—H bond activation polycyclic compounds
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A review of the surface activation and modification of biochars
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作者 Zhang Yihan Chen Longyi 《新型炭材料(中英文)》 北大核心 2026年第1期67-90,共24页
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen... Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed. 展开更多
关键词 Activation and modification Carbon material interface Surface functionalization Metal nanoparticle deposition Surface defect
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