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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 complex dicarboxylic acid catalytic properties Knoevenagel reaction
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Syntheses,crystal structures,catalytic and anti-wear properties of zinc(Ⅱ),nickel(Ⅱ)and cadmium(Ⅱ)complexes constructed from a terphenyl-tricarboxylate ligand
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作者 ZHAO Zhenghua LIU Yufeng +2 位作者 ZHANG Qing SHI Zifa GU Jinzhong 《无机化学学报》 北大核心 2026年第1期170-180,共11页
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc... Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3. 展开更多
关键词 complexES tricarboxylic acid catalytic properties Knoevenagel condensation reaction anti-wear performance
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Crystal structures of complexes of cyclobutanocucurbit[5]uril with Na^(+)/K^(+): Coordination state in different anionic environments
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作者 CHEN Wang WU Guixian +6 位作者 XIONG Yingying CHENG Ming ZHOU Mingming ZHANG Hui LIANG Zhengyun HUANG Dejin CHEN Minghua 《无机化学学报》 北大核心 2026年第1期161-169,共9页
The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th... The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4. 展开更多
关键词 cucurbit[n]uril supramolecular chemistry uril cucurbit[n]uril-metal complexes
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Advancements in the diagnosis and management of complex trimalleolar ankle fractures:A comprehensive review
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作者 Lorenzo Lucchetta Giampiero Mastroeni +3 位作者 Giuseppe Rinonapoli Auro Caraffa Saran Singh Gill Valerio Pace 《World Journal of Orthopedics》 2026年第1期1-12,共12页
Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current ev... Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes. 展开更多
关键词 Trimalleolar ankle fractures complex ankle fractures Trimalleolar fractures Fibula fractures Tibia fractures
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大气压下均匀场氮气间隙纳秒脉冲放电过程的三维PIC/MCC仿真研究
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作者 王永亮 李俊娜 +3 位作者 史浩良 李好 蒋铭 邱爱慈 《高电压技术》 北大核心 2025年第4期2037-2048,I0025,共13页
为研究几十纳秒脉冲电压下放电参数对气体火花开关间隙放电过程的影响机理,基于场致发射假设,采用三维粒子仿真模型模拟了大气压下均匀场氮气间隙在不同条件下的纳秒脉冲放电通道的形成和发展过程。通过调整脉冲电压上升时间、种子电子... 为研究几十纳秒脉冲电压下放电参数对气体火花开关间隙放电过程的影响机理,基于场致发射假设,采用三维粒子仿真模型模拟了大气压下均匀场氮气间隙在不同条件下的纳秒脉冲放电通道的形成和发展过程。通过调整脉冲电压上升时间、种子电子数密度和场增强因子等参数,研究了放电参数对电子崩和流注形态结构的影响。模拟结果表明:电子崩向阳极发展,流注向阳极和阴极同时发展,流注通道存在明显分叉现象,放电参数不同时,流注通道传播速度和形态结构存在差异;种子电子数密度一定时,脉冲电压上升时间越大,流注通道传播速度越小,分叉现象越严重。脉冲电压上升时间一定时,高种子电子数密度可以促进流注的形成和发展,减弱流注通道的分叉现象;高场增强因子可实现显著的预电离效果,有效促进流注通道的形成和发展,最大程度地减弱流注通道的分叉现象。 展开更多
关键词 纳秒脉冲放电 三维粒子模拟 均匀场氮气间隙 气体火花开关 流注通道分叉
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基于MCC-PCKF的跟网型变流器时变虚拟惯量与状态估计
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作者 王渝红 王雪珂 +3 位作者 文玉玲 郑宗生 廖建权 刘咏玥 《电力系统自动化》 北大核心 2025年第13期103-112,共10页
新能源接入下,非同步机的惯量估计对于应对系统有功功率扰动、保障系统稳定运行具有重要意义。针对新能源虚拟惯量的时变特性,建立跟网型新能源非同步机动态惯量与状态估计模型,采用混沌多项式卡尔曼滤波(PCKF)算法对电力系统的惯量参... 新能源接入下,非同步机的惯量估计对于应对系统有功功率扰动、保障系统稳定运行具有重要意义。针对新能源虚拟惯量的时变特性,建立跟网型新能源非同步机动态惯量与状态估计模型,采用混沌多项式卡尔曼滤波(PCKF)算法对电力系统的惯量参数及状态进行联合估计。在此基础上,考虑到异常噪声环境下PCKF算法精度下降、鲁棒性差等问题,采用最大熵原则,引入新的代价函数捕捉高阶统计量,提出一种基于最大熵准则-混沌多项式卡尔曼滤波(MCC-PCKF)的新能源非同步机时变虚拟惯量估计方法,有效提高了估计方法的鲁棒性与精确性。为验证所提方法的性能,对改进的IEEE 39节点系统进行算例分析,并与PCKF方法进行对比,验证了所提MCC-PCKF算法在异常噪声环境下时变惯量估计的鲁棒性与精确性。 展开更多
关键词 跟网型变流器 虚拟惯量 惯量估计 状态估计 最大熵准则 混沌多项式卡尔曼滤波
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MCC950纳米药物晶体的制备及体外性质研究
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作者 史蓉英 傅佳丽 +3 位作者 殷志杰 贺珊珊 张志荣 林箐 《华西药学杂志》 北大核心 2025年第2期127-130,共4页
目的制备MCC950纳米药物晶体(nanoMCC950),并进行表征,初步研究小鼠巨噬细胞对其的摄取。方法采用高压均质法制备nanoMCC950,运用单因素筛选法依次筛选高压均质时间、高压均质压力、稳定剂的组合;并对所制得纳米晶体的粒度分布、Zeta电... 目的制备MCC950纳米药物晶体(nanoMCC950),并进行表征,初步研究小鼠巨噬细胞对其的摄取。方法采用高压均质法制备nanoMCC950,运用单因素筛选法依次筛选高压均质时间、高压均质压力、稳定剂的组合;并对所制得纳米晶体的粒度分布、Zeta电位、形态、晶型稳定性进行表征。同时,应用共聚焦技术研究细胞的摄取情况。结果筛选出最优处方,成功制备了均一稳定的nanoMCC950,其粒径为349±3.75 dnm,分数系数为0.212,Zeta电位-29.5±0.20 mV。细胞摄取实验表明:nanoMCC950能被脂多糖诱导的炎性巨噬细胞摄取。结论MCC950能够制备成为纳米药物晶体,可为MCC950制剂的开发提供一种结构简单、性质稳定的制剂类型或制剂中间体。 展开更多
关键词 mcc950 纳米药物晶体 高压均质 稳定剂 炎性巨噬细胞 细胞摄取
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MCC950对H_(2)O_(2)诱导的软骨细胞焦亡和基质降解的影响
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作者 白荟 韩琳 +4 位作者 刘凯 马天文 卢爱桃 高瑞峰 杜山 《东北农业大学学报》 北大核心 2025年第1期104-111,共8页
为探究MCC950经NLRP3/caspase-1信号级联对软骨细胞焦亡和基质降解的调控作用,试验将14~21日龄SD大鼠原代软骨细胞分为4组:对照组(C组,完全培养基)、过氧化氢组(H组,300μmol·L^(-1)H2O2,24 h)、MCC950组(MC组,10μmol·L^(-1)... 为探究MCC950经NLRP3/caspase-1信号级联对软骨细胞焦亡和基质降解的调控作用,试验将14~21日龄SD大鼠原代软骨细胞分为4组:对照组(C组,完全培养基)、过氧化氢组(H组,300μmol·L^(-1)H2O2,24 h)、MCC950组(MC组,10μmol·L^(-1)MCC950+完全培养基)、MC+H组(H2O2处理前1 h,10μmol·L^(-1)MCC950预处理),分析使用MCC950抑制NLRP3炎性小体激活,观察软骨细胞经典焦亡通路关键蛋白、炎性反应和基质降解标志物的变化情况。结果表明:经MCC950预处理后,细胞培养上清中LDH释放率、IL-1β、IL-18、TNF-α和COX-2水平降低,经典焦亡通路关键蛋白和mRNA(NLRP3、caspase-1和GSDMD)表达下调,软骨细胞表达胶原分解标志物COMP和CTX-Ⅱ质量浓度降低,蛋白多糖合成标志物GAG质量浓度升高。MCC950经NLRP3/caspase-1通路可抑制软骨细胞焦亡、炎症和基质降解,发挥软骨保护作用。 展开更多
关键词 软骨细胞 NLRP3/caspase-1信号通路 细胞焦亡 炎症 mcc950
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Copper complexes of anthrahydrazone bearing pyridyl side chain:Synthesis,crystal structure,anticancer activity,and DNA binding 被引量:1
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作者 HUANG Yao WU Yingshu +5 位作者 BAO Zhichun HUANG Yue TANG Shangfeng LIU Ruixue LIU Yancheng LIANG Hong 《无机化学学报》 北大核心 2025年第1期213-224,共12页
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp... To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2. 展开更多
关键词 anthrahydrazone metal complex crystal structure anticancer activity cell apoptosis
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NLRP-3抑制剂MCC950对胃酸刺激诱导HEECs氧化应激、抗氧化蛋白及炎症因子表达的作用
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作者 阿布力克木·吾拉音 麦麦提依明·买买吐尔逊 +3 位作者 买买提·依斯热依力 王永康 吴朝阳 克力木·阿不都热依木 《中国现代医学杂志》 2025年第12期31-36,共6页
目的 探讨NOD样受体蛋白3(NLRP-3)抑制剂MCC950对胃酸刺激诱导人食管上皮细胞(HEECs)氧化应激、抗氧化蛋白及炎症因子表达的作用。方法 HEECs细胞经传代培养,将细胞分为空白对照组、酸刺激组、胆盐刺激组、脂多糖(LPS)处理组、MCC950预... 目的 探讨NOD样受体蛋白3(NLRP-3)抑制剂MCC950对胃酸刺激诱导人食管上皮细胞(HEECs)氧化应激、抗氧化蛋白及炎症因子表达的作用。方法 HEECs细胞经传代培养,将细胞分为空白对照组、酸刺激组、胆盐刺激组、脂多糖(LPS)处理组、MCC950预处理+酸刺激组、MCC950预处理+胆盐刺激组、MCC950预处理+LPS刺激组、N-乙酰半胱氨酸(NAC)预处理+酸刺激组、NAC预处理+胆盐刺激组、NAC预处理+LPS组等,每组细胞孵育48 h;并提取总RNA,后进行逆转录聚合酶链反应检测并分析氧化应激、抗氧化蛋白和炎症因子指标mRNA表达水平。结果 酸刺激组、胆盐刺激组和LPS处理组Nox-4 mRNA相对表达量较空白对照组高(P <0.05),酸刺激组、胆盐刺激组和LPS处理组Nrf-2、HO-1 mRNA相对表达量较空白对照组低(P <0.05)。MCC950+酸刺激组、MCC950+胆盐刺激组、MCC950+胆盐刺激组Nox-4 mRNA相对表达量分别较酸刺激组、胆盐刺激组、LPS处理组低(P <0.05),MCC950+酸刺激组、NAC+酸刺激组、MCC950+胆盐刺激组、NAC+胆盐刺激组、MCC950+LPS处理组、NAC+LPS处理组Nrf-2、HO-1 mRNA相对表达量分别较酸刺激组、胆盐刺激组、LPS处理组高(P <0.05)。酸刺激组、胆盐刺激组和LPS处理组MCP-1、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α) mRNA相对表达量较空白对照组高(P <0.05),CC950+酸刺激组、NAC+酸刺激组、MCC950+胆盐刺激组、NAC+胆盐刺激组、MCC950+LPS处理组、NAC+LPS处理组MCP-1、IL-6、TNF-α mRNA相对表达量分别较酸刺激组、胆盐刺激组、LPS处理组低(P <0.05)。结论 胃酸诱导HEECs细胞Nox-4高表达和抗氧化蛋白低表达,促进炎症因子的过量表达,MCC950能有效抑制炎症损伤的发生。 展开更多
关键词 胃酸 人食管上皮细胞 氧化应激 抗氧化蛋白 炎症因子 mcc950
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Active polarization high-resolution imaging through complex scattering media 被引量:2
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作者 Meng Xiang Xue Dong +6 位作者 Tianyu Wang Sen Wang Jingjing Ge Jinpeng Liu Qianqian Liu Fei Liu Xiaopeng Shao 《Advanced Photonics Nexus》 2025年第1期127-137,共11页
High-resolution seeing through complex scattering media such as turbid water,biological tissues,and mist is a significant challenge because the strong scattering scrambles the light paths and forms the scattering wall... High-resolution seeing through complex scattering media such as turbid water,biological tissues,and mist is a significant challenge because the strong scattering scrambles the light paths and forms the scattering wall.We propose an active polarized iterative optimization approach for high-resolution imaging through complex scattering media.By acquiring a series of sub-polarized images,we can capture the diverse pattern-illuminated images with various high-frequency component information caused by the Brownian motion of complex scattering materials,which are processed using the common-mode rejection of polarization characteristics to extract target information from scattering medium information.Following that,our computational reconstruction technique employs an iterative optimization algorithm that commences with patternilluminated Fourier ptychography for reconstructing the high-resolution scene.It is extremely important that our approach for high-resolution imaging through complex scattering media is not limited by priori information and optical memory effect.The proposed approach is suitable for not only dynamic but also static scattering media,which may find applications in the biomedicine field,such as skin abnormalities,non-invasive blood flow,and superficial tumors. 展开更多
关键词 complex scattering media iterative optimization POLARIZATION Fourier ptychography.
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A mitochondria targeting Ir(Ⅲ)complex triggers ferroptosis and autophagy for cancer therapy:A case of aggregation enhanced PDT strategy for metal complexes 被引量:2
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作者 Panpan Wang Hongbao Fang +5 位作者 Mengmeng Wang Guandong Zhang Na Xu Yan Su Hongke Liu Zhi Su 《Chinese Chemical Letters》 2025年第1期374-380,共7页
Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxyge... Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxygen species(ROS),and aggregation-induced ROS quenching.To address these challenges,we present a molecular self-assembly strategy utilizing aggregation-induced emission(AIE)conjugates for metal complexes.As a proof of concept,we synthesized a mitochondrial-targeting cyclometalated Ir(Ⅲ)photosensitizer Ir-TPE.This approach significantly enhances the photodynamic effect while mitigating the dark toxicity associated with AIE groups.Ir-TPE readily self-assembles into nanoaggregates in aqueous solution,leading to a significant production of ROS upon light irradiation.Photoirradiated Ir-TPE triggers multiple modes of death by excessively accumulating ROS in the mitochondria,resulting in mitochondrial DNA damage.This damage can lead to ferroptosis and autophagy,two forms of cell death that are highly cytotoxic to cancer cells.The aggregation-enhanced photodynamic effect of Ir-TPE significantly enhances the production of ROS,leading to a more pronounced cytotoxic effect.In vitro and in vivo experiments demonstrate this aggregation-enhanced PDT approach achieves effective in situ tumor eradication.This study not only addresses the limitations of metal complexes in terms of low ROS production due to aggregation but also highlights the potential of this strategy for enhancing ROS production in PDT. 展开更多
关键词 Metal complex AIEgens Mitochondria targeting Enhanced photodynamic therapy Anticancer agent
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MCC引发的一次短时强降水环境场和云参数特征
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作者 乔丹杨 王瑾婷 +3 位作者 刘帆 卢晔 高萌 谢逸雯 《陕西气象》 2025年第2期1-8,共8页
利用常规观测资料、欧洲中心ERA5再分析资料以及FY-4A卫星定量产品,对2022年7月15日陕西关中东部中尺度对流复合体(mesoscale convective complex, MCC)引发的一次短时强降水过程发生的环境场和云特性参数进行了分析。结果表明:(1)此次... 利用常规观测资料、欧洲中心ERA5再分析资料以及FY-4A卫星定量产品,对2022年7月15日陕西关中东部中尺度对流复合体(mesoscale convective complex, MCC)引发的一次短时强降水过程发生的环境场和云特性参数进行了分析。结果表明:(1)此次过程发生在副高、短波槽和低涡切变线共同影响的环流背景下,前期受副高控制不稳定能量持续积累,水汽条件充沛,在地面辐合线动力抬升作用下触发对流,造成短时强降水。(2)大范围短时强降水发生在MCC成熟阶段,当≤-52℃冷云面积达到最大时,降水强度达到最大,当≤-52℃冷云面积开始减小时,降水强度开始减弱。(3)短时强降水主要分布在地面辐合线附近,且其上空对应的冷云区T_(BB)≤-72℃,同时云顶高度发展至16 km以上。短时强降水发生前,TBB呈波动下降、云顶高度呈波动上升的特征。当TBB(T_(BB))、TBB平均值(T_(BBavg))和TBB最小值(T_(BBmin))越小,最大TBB梯度(G)和TBB变化率(R)越大时,雨强越大。 展开更多
关键词 mcc 短时强降水 FY-4A 黑体亮度温度(TBB) 云顶高度(CTH)
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Data-Driven Prediction in Complex Systems of Virus Evolution and Global Warming 被引量:1
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作者 LUO Liaofu LÜJun 《内蒙古大学学报(自然科学版)》 2025年第1期1-7,共7页
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da... A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500. 展开更多
关键词 data-drivenprediction complex system virus evolution global warming
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Exploring the Effects of Background Image Complexity and Map Symbol Load on the Usability of Image-maps 被引量:1
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作者 PENG Qian XIA Yuxin QIU Zeren 《Journal of Geodesy and Geoinformation Science》 2025年第2期5-20,共16页
Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps i... Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps is influenced by the representations of background images and map symbols.Many researchers explored the optimizations for background images and symbolization techniques for symbols to reduce the complexity of image-maps and improve the usability.However,little literature was found for the optimum amount of symbol loading.This study focuses on the effects of background image complexity and map symbol load on the usability(i.e.,effectiveness and efficiency)of image-maps.Experiments were conducted by user studies via eye-tracking equipment and an online questionnaire survey.Experimental data sets included image-maps with ten levels of map symbol load in ten areas.Forty volunteers took part in the target searching experiments.It has been found that the usability,i.e.,average time viewed(efficiency)and average revisits(effectiveness)of targets recorded,is influenced by the complexity of background images,a peak exists for optimum symbol load for an image-map.The optimum levels for symbol load for different image-maps also have a peak when the complexity of the background image/image map increases.The complexity of background images serves as a guideline for optimum map symbol load in image-map design.This study enhanced user experience by optimizing visual clarity and managing cognitive load.Understanding how these factors interact can help create adaptive maps that maintain clarity and usability,guiding AI algorithms to adjust symbol density based on user context.This research establishes the practices for map design,making cartographic tools more innovative and more user-centric. 展开更多
关键词 remote sensing image map point label complexity
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基于MCC加权的LSSVR容控箱液位异常检测
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作者 周光荣 郑胜 +1 位作者 杨森权 易爽 《计算机仿真》 2025年第4期496-501,共6页
由于日益增长的运行安全需求,数字化和智能化的核电厂状态监测变得越来越重要。为了解决核电数据缺乏清晰的数据标签,影响模型精度的问题,提出了一种基于最大相关熵准则(Maximum Correntropy Criterion,MCC)加权的最小二乘法支持向量(Le... 由于日益增长的运行安全需求,数字化和智能化的核电厂状态监测变得越来越重要。为了解决核电数据缺乏清晰的数据标签,影响模型精度的问题,提出了一种基于最大相关熵准则(Maximum Correntropy Criterion,MCC)加权的最小二乘法支持向量(Least squares support vector regression,LSSVR)回归方法。首先,提取容积控制箱(Volume Control Tank,VCT)相关变量的数据并进行预处理;其次,利用MCC加权的LSSVR方法来建立VCT液位回归模型;最后,结合上述模型的回归值和真实值判断是否出现异常。实验结果表明,基于MCC加权的LSSVR方法相较于普通的LSSVR方法,其能够更有效的抑制训练数据中的异常,从而提高模型的鲁棒性,并能够准确地检测出测试集中的异常数据。 展开更多
关键词 核电运行安全 异常检测 最大相关熵 最小二乘法支持向量回归 容积控制箱
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Zircon U-Pb-Hf and Trace Element Signatures Reveal the Petrogenesis of the Jiuyishan Granitic Complex,South China:Implications for W-Sn and Rare Metal Mineralization 被引量:1
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作者 Wenzhou Xiao Chaoyun Liu +6 位作者 Kaixuan Tan Xianzhe Duan Qinglin Sui Kaituo Shi Peng Feng Mabrouk Sami Quan Ou 《Journal of Earth Science》 2025年第3期1069-1089,共21页
The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,... The Jiuyishan granitic complex,located in the Nanling Range,South China,is composed of five granitic plutons(Xuehuading,Jinjiling,Pangxiemu,Shaziling and Xishan).Zircon U-Pb dating of four plutons(Jinjiling,Pangxiemu,Shaziling and Xishan)yielded similar ages of approximately 153 Ma,indicating indistinguishable ages within error.Three plutons except the Shaziling pluton,have consistentε_(Nd)(t)(-7.8 to-5.8)andε_(Hf)(t)(-9.1 to-2.2)values,which are similar to those of the lower crustal granulitic metasedimentary and meta-igneous rocks in South China.Compared to other three plutons,the Shaziling pluton has consistentε_(Nd)(t)(-7.4 to-6.8)andε_(Hf)(t)(-7.5 to-4.7)values and shows similar source,but the Shaziling mafic microgranular enclaves(MMEs)show variableε_(Hf)(t)(-14.2 to 4.8)values,indicating a remarkable mantle magma injection of the Shaziling pluton.Zircon Ce/Sm-Yb/Gd,whole-rock CaO-P_(2)O_(5)and CaO-TiO_(2)linear trends reveal that from the Xishan to the Shaziling and from the Jinjiling to the Pangxiemu granites,they experienced apatite and titanite fractionation,respectively.Zircon Th,U,Nb,Ta,Hf,Ti,Y,P and rare earth element(REE)contents and whole-rock Sr,Ba and Rb contents also show that the Shaziling,Xishan,Jinjiling and Pangxiemu granites followed a discontinuous evolutionary series,but the Pangxiemu granites exhibit highly evolved nature.Four main controlling factors of W-Sn and rare metal mineralization in granitic rocks were discussed,and we found that the mineralization in Jiuyishan granitic complex was mainly controlled by the fractionation degree and crystallization temperature,but were rarely affected by oxygen fugacity and mantle material input.The Pangxiemu granites show particularly higher Rb and Ta contents than the other three plutons,implying that the ore deposits developed in the Jiuyishan Complex were directly related to the most evolved Pangxiemu pluton,with the occurrence of Rb and Ta as the most likely rare metal mineralization in the Jiuyishan District.A crystal mush model is proposed to interpret the petrogenetic and mineralizing processes of the Jiuyishan granitic complex. 展开更多
关键词 Jiuyishan granitic complex ZIRCON fractionation geochemistry rare metal mineralization
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基于FY-4A的中国东北地区两类MCC特征
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作者 于佳含 朱晓彤 +2 位作者 谭政华 王婷婷 李吉 《气象灾害防御》 2025年第4期1-7,共7页
基于FY-4A气象卫星数据、欧洲中心ERA5数据和三源融合实况格点降水数据,对2021—2022年6—8月中国东北地区的7个MCC,按影响区域分为北部类和南部类的基础上,对两类MCC及其强降水的时空演变特征进行详细分析。结果发现:对流层高层风对MC... 基于FY-4A气象卫星数据、欧洲中心ERA5数据和三源融合实况格点降水数据,对2021—2022年6—8月中国东北地区的7个MCC,按影响区域分为北部类和南部类的基础上,对两类MCC及其强降水的时空演变特征进行详细分析。结果发现:对流层高层风对MCC的移动有决定性作用,云顶最低亮温多偏于云团高层风迎风侧或接近云团中部,亮温梯度大值区多出现在初生阶段和发展成熟阶段中前期,较贴近云团高层风迎风侧或风向两侧的外围;云顶高度的极值和梯度在方位上与亮温特征相似,较高的云顶一般对应较低的亮温;强降水主要位于云团中部、高层风迎风侧及其左侧,其较大面积时段出现在MCC发展成熟阶段中后期至减弱阶段前期。此外,南部类MCC在最大面积、三阶段比例、生命史长度、生成和消散时刻等方面差异较大,且面积曲线快速增长时段较多,最大峰值更凸出,亮温梯度整体更大;北部类相反,并在发展成熟阶段中后期出现了≥50 mm·h^(-1)的强降水。 展开更多
关键词 中尺度对流复合体(mcc) 云顶最低亮温 亮温梯度 云顶高度
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Unraveling the cryogenic formability in high entropy alloy sheets under complex stress conditions 被引量:1
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作者 Ke-Yan Wang Zi-Jian Cheng +6 位作者 Zhi-Liang Ning Hai-Ping Yu Parthiban Ramasamy Jürgen Eckert Jian-Fei Sun Alfonso H.W.Ngan Yong-Jiang Huang 《Rare Metals》 2025年第2期1332-1341,共10页
This work investigates how temperature and microstructural evolution affect the formability of face-centered cubic(fcc)structured CoCrFeNiMn_(0.75)Cu_(0.25) high entropy alloy(HEA)sheets under complex stress condition... This work investigates how temperature and microstructural evolution affect the formability of face-centered cubic(fcc)structured CoCrFeNiMn_(0.75)Cu_(0.25) high entropy alloy(HEA)sheets under complex stress conditions.Erichsen cupping tests were conducted to quantitatively evaluate the deformation capacity at room temperature(298 K)and cryogenic temperatures.The findings reveal a strong temperature dependence on the formability of the HEA.A decrease in the deformation temperature from 298 to 93 K causes a significant increase in both the Erichsen index(IE)(from 9.8 to 12.4 mm)and the expansion rate(δ)of surface area(from 51.6%to 76.3%),as well as a reduction in the average deviation(η)of thickness(from 55.1%to 44.4%),signifying its ultrahigh formability and uniform deformation capability at cryogenic temperature.This enhancement is attributed to the transition in the deformation mechanism from single dislocation slip at 298 K to a cooperative of plastic deformation mechanisms at 93 K,involving dislocation slip,stacking faults(SFs),Lomer-Cottrell(L-C)locks and multi-scale nanotwins.The lower stacking fault energy of the alloy facilitates these deformation mechanisms,particularly the formation of SFs and nanotwins,which enhance ductility and strength by providing additional pathways for plastic deformation.These mechanisms collectively contribute to delaying plastic instability,thereby improving the overall formability.This work provides a comprehensive understanding of the underlying reasons for the enhanced formability of HEAs at cryogenic temperatures,offering valuable insights for their practical use in challenging environments. 展开更多
关键词 High entropy alloys Cryogenic formability Deformation mechanism complex stress
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