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Simulation Analysis of the Extrusion Process for Complex Cross-Sectional Profiles of Ultra-High Strength AluminumAlloy
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作者 Tianxia Zou Yilin Sun +3 位作者 Fuhao Fan Zhen Zheng Yanjin Xu Baoshuai Han 《Computers, Materials & Continua》 2026年第4期471-491,共21页
Ultra-high-strength aluminumalloy profile is an ideal choice for aerospace structuralmaterials due to its excellent specific strength and corrosion resistance.However,issues such as uneven metal flow,stress concentrat... Ultra-high-strength aluminumalloy profile is an ideal choice for aerospace structuralmaterials due to its excellent specific strength and corrosion resistance.However,issues such as uneven metal flow,stress concentration,and forming defects are prone to occur during their extrusion.This study focuses on an Al-Zn-Mg-Cu ultra-high-strength aluminum alloy profile with a double-U,multi-cavity thin-walled structure.Firstly,hot compression experiments were conducted at temperatures of 350○C,400○C,and 450○C,with strain rates of 0.01 and 1.0 s^(−1),to investigate the plastic deformation behavior of the material.Subsequently,a 3D coupled thermo-mechanical extrusion simulation model was established using Deform-3D to systematically analyze the influence of die structure and process parameters on metal flow velocity,effective stress/strain,and temperature distribution.The simulation revealed significant velocity differences,stress concentration,and uneven temperature distribution.Key parameters,including mesh density,extrusion ratio,die fillet,and bearing length,were optimized through full-factorial experiments.This optimization,combined with a stepped flow-guiding die design,effectively improved the metal flow pattern during extrusion.Trial production based on both the initial and optimized parameters were carried out.A comparative analysis demonstrates that the optimized scheme results in a final profile whose cross-section matches the target design closely,with complete filling of complex features and no obvious forming defects.This research provides a valuable reference for the extrusion process optimization and die design of complex-section profiles made from ultra-high-strength aluminum alloys. 展开更多
关键词 Ultra-high-strength aluminum alloy EXTRUSION complex cross-section die optimization process optimization
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断块油藏SEC准则储量评估方法——以海拉尔油田复杂断块油藏为例
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作者 贾红兵 郭明日 +4 位作者 于东旭 杨慧 孙贻铃 孔凡顺 李亚光 《大庆石油地质与开发》 北大核心 2026年第1期80-86,共7页
海拉尔油田为陆相断陷盆地背景的复杂断块油藏群,具有多级序断层发育、多物源快速沉积、储集空间孔缝洞并存、多成因成藏等特点,为满足SEC准则证实储量评估需求,开展了断块油藏SEC储量评估方法研究。针对复杂断块油藏特点,从含油面积圈... 海拉尔油田为陆相断陷盆地背景的复杂断块油藏群,具有多级序断层发育、多物源快速沉积、储集空间孔缝洞并存、多成因成藏等特点,为满足SEC准则证实储量评估需求,开展了断块油藏SEC储量评估方法研究。针对复杂断块油藏特点,从含油面积圈定、有效储层识别、类比油藏采收率、分层储量确定等方面,探索研究适合断块油藏的容积法储量评估关键技术,提出了同沉积断层、遮挡型断层和渗透性断层不同级序断层边界含油面积圈定的量化方法,形成砂、砾、灰混杂储层的“三分法”储量参数解释技术,建立了断块油藏采收率全序列类比油藏,创建出合采压裂井的分层证实储量计算模型。研究形成的断块油藏评估可靠技术及合理性方法,在证实储量评估实践中得到有效应用,对同类油藏SEC储量科学评估具有一定借鉴意义。 展开更多
关键词 断块油藏 sec 含油面积 储量参数 类比油藏 分层储量
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致密油SEC储量评估技术及方法
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作者 王天煦 唐振兴 +3 位作者 赵家宏 王武学 江海英 孙立鹏 《大庆石油地质与开发》 北大核心 2026年第1期102-108,共7页
致密油藏与常规油藏在渗流特征和开发规律上存在显著差异。为了准确评估致密油的证券交易委员会(SEC)储量,建立了折耗与主要影响因素的理论模型,明确了折耗优化方向,并提出适合致密油藏的开发策略和储量评估方法。首先,分析了SEC储量对... 致密油藏与常规油藏在渗流特征和开发规律上存在显著差异。为了准确评估致密油的证券交易委员会(SEC)储量,建立了折耗与主要影响因素的理论模型,明确了折耗优化方向,并提出适合致密油藏的开发策略和储量评估方法。首先,分析了SEC储量对油气资产折耗的影响现状;其次,通过动态法和容积法评估致密油储量,建立了折耗与主要影响因素的理论模型;最后,提出快速建产、匀速建产和补充稳产3种开发策略,并探索了适合致密油的容积法储量评估方法,创新性地应用地球物理信息和水平井泄油半径来圈定含油面积,形成基于相似性数学模型确定采收率的类比方法。结果表明:补充稳产模式为最佳开发策略;证实已开发储量(PD储量)的最佳评估方式为油田级评估;建立了适合致密油两段式递减规律的储量起算标准计算模型,确定了应用相似性数学模型定性定量分析优选类比油藏的方法。研究成果对合理合规评估同类型致密油SEC储量具有重要的借鉴意义。 展开更多
关键词 致密油 sec储量 动态法评估 容积法评估
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禾谷镰孢磷脂酰肌醇转运蛋白FgSec14对磷脂分子转运的结构模型分析
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作者 尹延宗 赵雨薇 +4 位作者 陈紫阳 李佳琪 郑爽 刘颖超 赵斌 《河北农业大学学报》 北大核心 2026年第1期38-45,共8页
禾谷镰孢引起小麦赤霉病和玉米穗腐病等谷物病害,并产生真菌毒素威胁国家粮食安全。磷脂酰肌醇转运蛋白(Sec14)在生命过程中执行重要功能,但其在禾谷镰孢中的功能尚不清晰,本研究将获得FgSec14与磷脂分子的转运模型。利用ProtParam、Pro... 禾谷镰孢引起小麦赤霉病和玉米穗腐病等谷物病害,并产生真菌毒素威胁国家粮食安全。磷脂酰肌醇转运蛋白(Sec14)在生命过程中执行重要功能,但其在禾谷镰孢中的功能尚不清晰,本研究将获得FgSec14与磷脂分子的转运模型。利用ProtParam、ProtScale、WoLF PSORT和Clustal X等在线工具对FgSec14的生理生化特征及同源性进行了分析;通过原核表达和亲和镍柱层析方法获得了目的蛋白,利用荧光滴定技术检测了其与磷脂分子的结合情况,并通过Docking技术进行验证。结果表明,FgSec14为亲水性蛋白,其蛋白二级结构以α-螺旋和无规则卷曲为主,并在镰孢菌中高度保守,具有典型的Sec14和CRAL结构域;其主要通过与PA、PI、PS、PC和PE等分子的结合行驶磷脂转运功能,其中Arg^(50)、Arg^(206)、Arg^(58)为主要结合位点。研究结果将为靶向镰孢菌Sec14的新型杀菌剂开发提供了理论基础。 展开更多
关键词 禾谷镰孢 sec14 生物信息学分析 原核表达
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基于SEC模式的物理试题与课程标准一致性研究——以2022—2024年成都市中考为例
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作者 刘畅 兰小刚 《中学物理教学参考》 2026年第5期14-16,共3页
采用本土化的SEC模式,对2022—2024年成都市中考物理试题与课程标准进行一致性分析。结果表明:近三年成都市中考物理试题与课程标准一致性较强,其中2024年的最高。从内容主题分布来看,考查范围、重点分布与课程标准的要求基本一致;从核... 采用本土化的SEC模式,对2022—2024年成都市中考物理试题与课程标准进行一致性分析。结果表明:近三年成都市中考物理试题与课程标准一致性较强,其中2024年的最高。从内容主题分布来看,考查范围、重点分布与课程标准的要求基本一致;从核心素养角度来看,“物理观念”与“科学态度与责任”维度的考查占比基本与课程标准持平,“科学思维”维度的考查占比略高于课程标准,而“科学探究”维度的考查占比略低于课程标准。 展开更多
关键词 sec模式 课程标准 中考物理 一致性分析
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Full-dimensional complex coherence properties tomography for multi-cipher information security
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作者 Yonglei Liu Siting Dai +4 位作者 Yimeng Zhu Yahong Chen Peipei Peng Yangjian Cai Fei Wang 《Opto-Electronic Advances》 2025年第8期54-66,共13页
Optical coherence is a fundamental property of light,playing a key role in understanding interference,propagation,and light-matter interactions for both classical and quantum light.Measuring the coherence properties o... Optical coherence is a fundamental property of light,playing a key role in understanding interference,propagation,and light-matter interactions for both classical and quantum light.Measuring the coherence properties of an optical field is crucial for a wide range of applications.However,despite many proposed measurement schemes,significant challenges still remain.In this work,we present a protocol to measure the full-dimensional coherence properties of a partially coherent beam.The method is based on tomographing the complex coherent modes of the partially coherent field within its coherence time.Once the complex coherent modes are reconstructed,all coherence properties including field correlation and its higher-order correlations(e.g.,intensity correlation)can be recovered for beams that are either spatially uniformly or non-uniformly correlated.We perform a proof-of-principle experiment to measure the complex field correlation and intensity correlation of a structured partially coherent beam synthesized by random modes.Additionally,we discuss the application of full-dimensional complex coherence function tomography in coherence-based multi-cipher information security.The robustness of our system in complex environments is also evaluated. 展开更多
关键词 partially coherent light complex coherence measurement optical encryption structured light
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The role of psychological meaningfulness in the relationship between job complexity and work-family conflict among secondary school teachers in Nigeria
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作者 Gabriel C.Kanu Noah Adeji +3 位作者 Tobias C.Obi Elom S.Omena Raphael U.Anike Alexander U.Amaechi 《Journal of Psychology in Africa》 2025年第1期1-5,共5页
This study examined how psychological meaningfulness moderates job complexity and work-family conflict in Nigerian secondary school teachers.This study included 1694 teachers from 17 Nigerian secondary schools(female=6... This study examined how psychological meaningfulness moderates job complexity and work-family conflict in Nigerian secondary school teachers.This study included 1694 teachers from 17 Nigerian secondary schools(female=69.54%,mean age=33.19,SD=6.44 years).The participants completed the Work-family Conflict Scale,Job Complexity Scale,and Psychological Meaningfulness Scale.Study design was cross-sectional.Hayes PROCESS macro analysis results indicate a higher work-family conflict with job complexity among the secondary school teachers.While psychological meaningfulness was not associated with work-family conflict,it moderated the link between job complexity and work-family conflict in secondary school teachers such that a meaningful work endorsement is associated with lower employee’s work-life conflict.Thesefindings point to the importance of job functions to quality of family life.The studyfindings also suggest a need for supporting psychological meaningfulness for healthy work related quality of family life based on balancing work and family role demands. 展开更多
关键词 psychological meaningfulness job complexity work-family conflict secondary school TEACHERS
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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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Second overtone thickness-extensional vibrations in ZnO piezoelectric film bulk acoustic resonators:modified algorithm for 2D complex transcendental equations
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作者 Zinan Zhao Nian Li +1 位作者 Feng Zhu Weiqiu Chen 《Acta Mechanica Sinica》 2025年第11期89-100,共12页
This article investigates the second overtone thickness-extensional(TE2)vibrations and associated mode-coupling behaviors in ZnO piezoelectric film bulk acoustic resonator(FBAR),utilizing its wave dispersion relation ... This article investigates the second overtone thickness-extensional(TE2)vibrations and associated mode-coupling behaviors in ZnO piezoelectric film bulk acoustic resonator(FBAR),utilizing its wave dispersion relation and the higher-order stress balance principle.By superimposing the general wave solutions of multiple eigenmodes within the frequency range of the TE2 mode,mode-coupling solutions for ZnO FBAR are constructed.The substitution of these mode-coupling solutions into the higher-order stress balance principle,as laterally weak boundary conditions,leads to the frequency spectrogram equation,determining the relationship between resonance frequency and plate length-to-thickness ratio.A modified algorithm that combines the bisection method and the complex modulus ratio method is developed to solve the dispersion equation and frequency spectrogram equation(namely a kind of 2D complex transcendental equations)accurately and efficiently.The obtained results indicate that the operational TE2 mode may couple to unwanted 3^(rd)thickness-shear,fundamental thickness-shear,and flexural modes.Moreover,the mode-coupling behaviors depend strongly on resonance frequencies and plate length-to-thickness ratio.The displacement distributions of total displacement components,alongside the main displacement com-ponents of all considered eigenmodes,clearly demonstrate the variety of coupling behaviors.According to the obtained frequency spectrograms,the desirable values of plate length-to-thickness ratio for a clean operating mode with very weak coupling intensity are determined.These findings are of vital importance for the understanding of the mode-coupling me-chanism in overtone thickness-extensional FBARs,which will facilitate the structural design and optimization of FBAR devices. 展开更多
关键词 Piezoelectric film bulk acoustic resonator Overtone thickness-extensional mode Mode coupling Frequency spectrogram complex transcendental equation
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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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Acute zonal occult outer retinopathy complex and angioid streaks:a case report
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作者 Zhen-Yu Liu Hang Zhang +1 位作者 Xiu-Li Sun Xiao-Yan Peng 《International Journal of Ophthalmology(English edition)》 2026年第1期193-196,共4页
Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for mor... Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for more than 3y.She was diagnosed with ASs and choroiditis at a local hospital.She has a seven-year history of bilateral high myopia.A fundus examination confirmed the presence of ASs and myopic fundus changes in both eyes.Multimodal imaging revealed an AZOOR complex in the left eye. 展开更多
关键词 myopic fundus changes zonal occult outer retinopathy azoor complex Angioid Streaks Acute Zonal Occult Outer Retinopathy MYOPIA fundus examination angioid streaks ass azoor complex
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Non-equilibrium hydrogel with time-dependent ultrabright fluorescence fabricated by CB-mediated thermodynamic equilibrium host-vip complexes
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作者 Hanren Xu Hongyu An +1 位作者 Qian Wang Da-Hui Qu 《Science China Chemistry》 2026年第2期932-938,共7页
While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these fe... While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications. 展开更多
关键词 fluorescent hydrogel host-vip complexes information encryption dynamic fluorescence
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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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基于MRI-DWI参数联合血清sEC、HOTAIR构建浸润性乳腺癌复发风险预测模型
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作者 申玉霞 刘涛 +1 位作者 李建丽 李欢欢 《影像科学与光化学》 2026年第2期74-82,90,共10页
目的:探讨基于磁共振扩散加权成像(MRI-DWI)参数联合血清可溶性内皮细胞标志物(sEC)、HOTAIR构建浸润性乳腺癌复发风险预测模型的可行性及预测效能,为准确评估浸润性乳腺癌患者复发风险、制定个体化随访和干预策略提供依据。方法:纳入... 目的:探讨基于磁共振扩散加权成像(MRI-DWI)参数联合血清可溶性内皮细胞标志物(sEC)、HOTAIR构建浸润性乳腺癌复发风险预测模型的可行性及预测效能,为准确评估浸润性乳腺癌患者复发风险、制定个体化随访和干预策略提供依据。方法:纳入邯郸市中心医院2021年1月至2022年12月期间就诊的165例浸润性乳腺癌患者作为训练集,同期63例患者作为验证集(回顾性队列研究)。收集临床病理资料,检测血清sEC浓度、HOTAIR表达水平,行MRI-DWI检查获取表观扩散系数(ADC)、早期信号强化、峰值信号强化等参数。术后随访2年,记录复发情况。通过单因素分析筛选差异显著指标,纳入Cox回归模型构建列线图,并采用Bootstrap法进行内部(训练集)与外部(验证集)验证,以C-index、ROC曲线评估预测效能。结果:训练集165例中,术后2年复发41例(24.85%)。单因素分析显示,复发组淋巴结转移数目、临床TNM分期Ⅱ~Ⅲ期占比、Ki-67指数、早期信号强化、峰值信号强化、sEC、HOTAIR值显著更高,ADC值更低(P<0.05)。Cox回归表明,ADC值为独立保护因素,淋巴结转移数目、早期信号强化、峰值信号强化、sEC、HOTAIR为独立危险因素(P<0.05)。列线图模型在训练集的C-index为0.820(95%CI:0.781~0.864),AUC为0.806(95%CI:0.732~0.866);在验证集的C-index为0.805(95%CI:0.766~0.847),AUC为0.786(95%CI:0.678~0.893),校正曲线与理想曲线拟合良好。结论:基于MRI-DWI参数联合血清sEC、HOTAIR构建列线图模型具有良好复发风险预测效能,整合影像学功能特征与分子生物学标志物,能够准确评估浸润性乳腺癌患者的复发风险,为临床医生制定个体化的随访和干预策略提供重要依据。 展开更多
关键词 浸润性乳腺癌 磁共振成像 扩散加权成像 可溶性内皮细胞标志物 HOTAIR 复发风险
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Cisplatin-polyphenol complex liposomes reduce chemotherapy toxicity
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作者 Yizhi Ge Jiahui Zou +2 位作者 Hui Liu Wei He Huanfeng Zhu 《Chinese Chemical Letters》 2026年第1期492-496,共5页
Cisplatin(CDDP)-based chemotherapy is an effective strategy for the treatment of advanced nasopharyngeal carcinoma(NPC).However,serious toxic side effects of CDDP limit patient tolerance and treatment compliance,which... Cisplatin(CDDP)-based chemotherapy is an effective strategy for the treatment of advanced nasopharyngeal carcinoma(NPC).However,serious toxic side effects of CDDP limit patient tolerance and treatment compliance,which urgently needs to be addressed in clinical application.Liposomes have been considered ideal vehicles for reducing CDDP toxicity due to their high biocompatibility,low toxicity and passive targeting ability.Nevertheless,CDDP's poor water/lipid solubility usually results in a low liposome druglipid ratio,limiting tumor delivery ability.Herein,a CDDP-polyphenol complex liposome was designed to increase the drug loading capacity of CDDP to realize the reduction of toxicity and effective antitumor effect simultaneously.The complex was prepared via complexation reaction of different stoichiometric ratios of CDDP and polyphenolic substances(gallic acid,epigallocatechin gallate and tannic acid),followed by encapsulation of complex in liposomes to improve tumor targeting.Notably,the molecular interaction forces between CDDP and polyphenolic substances were intensively investigated through a binding force disruption assay.In vitro studies demonstrated that the optimal formulation of CDDP-epigallocatechin gallate complex liposome(CDDP-EGCG Lips) showed the highest CDDP encapsulation efficiency,favorable stability,pH-sensitive release,enhanced cellular uptake and apoptosis effect.In vivo studies revealed that CDDP-EGCG Lips retarded the elimination of CDDP to prolong their circulation time,inhibited the growth of tumors,and significantly reduced the toxic side effects compared to CDDP monotherapy.This delivery strategy holds great promise for improving the clinical use of platinum-based drugs. 展开更多
关键词 CISPLATIN Polyphenolic substances CDDP-polyphenol complex LIPOSOME Toxic side effect
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Diverse polyoxometalate-based cobalt complexes for catalyzing olefin epoxidation reaction at room temperature:regulation of active sites by polyoxometalate templates
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作者 Zhixuan An Xiaohui Li +3 位作者 Xuejiao Wang Chenlu Zhang Hui Li Xiuli Wang 《Science China Materials》 2026年第3期1573-1580,共8页
Enhancing the catalytic activity of catalysts is a core objective in their design and synthesis processes,and the accessibility of active sites is one of the crucial factors determining catalyst activity.Polyoxometala... Enhancing the catalytic activity of catalysts is a core objective in their design and synthesis processes,and the accessibility of active sites is one of the crucial factors determining catalyst activity.Polyoxometalate-based metal-organic complexes(POMOCs)with well-defined structures,which combine the advantages of POMs and MOCs,may offer the possibility to construct catalysts with highly accessible active sites.In this study,a series of POMOCs were successfully designed and synthesized using different POM templates,including[CoII1.5(L)1.5(PMo12O40)(H_(2)O)4]·3H_(2)O(Co-PMo12),[CoII1.5(L)1.5(PW12O40)(H_(2)O)4]·3H_(2)O(Co-PW12),[CoII2(L)2-(SiW12O40)(H_(2)O)4]·11H_(2)O(Co-SiW12),and H[CoII2.5(L)3-(P2W18O62)(H_(2)O)8]·10H_(2)O(Co-P2W18),which were characterized by Fourier transform infrared spectroscopy,powder X-ray diffraction,and single crystal X-ray diffraction.The differences in catalytic activity among the four POMOCs for olefin epoxidation were attributed to the distinct accessibility of Co(II)sites upon thermal activation.Among them,Co-P2W18 achieved a remarkable 99%yield of 1,2-epoxycyclooctane within 3 h at room temperature using O_(2)as the oxidant,owing to its highly accessible unsaturated Co(II)sites.Co-P2W18 exhibits significantly superior catalytic activity for the cyclooctene epoxidation reaction compared to most reported catalysts.Additionally,the reaction mechanism was investigated using density functional theory. 展开更多
关键词 polyoxometalate-based metal-organic complex coordination unsaturated Co polyoxometalate templates olefin epoxidation
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Rational design of n-type organic thermoelectric materials:Insights from CnBTBT-F_(m)TCNQ charge-transfer complexes
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作者 Hongchao Wang Wei Hao +6 位作者 Haowei Wu Qianyu Ding Yu Wei Hu Zhao Shuzhou Li Hanying Li Jia Zhu 《Chinese Chemical Letters》 2026年第2期489-493,共5页
Charge-transfer complexes(CTCs)have emerged as promising n-type organic thermoelectric(TE)materials due to their inherent high electrical conductivity and tunable transport polarities.In this study,we performed a comp... Charge-transfer complexes(CTCs)have emerged as promising n-type organic thermoelectric(TE)materials due to their inherent high electrical conductivity and tunable transport polarities.In this study,we performed a comprehensive first-principles investigation on the TE properties of nine CTCs comprised of 2,7-dialkyl[1]benzothieno[3,2-b][1]benzothiophenes(CnBTBT,n=4,8,12)as donors and fluorinated derivatives of tetracyanoquinodimethane(F_(m)TCNQ,m=0,2,4)as acceptors,aiming to identify high-performance n-type organic TE materials and elucidate the underlying structure-property relationships.Our calculation results,based on the Boltzmann transport equation and deformation potential theory,reveal that the length of the alkyl side chains and the number of fluorine substitutions significantly impact their electronic structures and TE properties.Notably,the CnBTBT-F_(m)TCNQ CTCs with shorter alkyl chains and more fluorine substitution demonstrate superior n-type characteristics,particularly C4BTBT-F4TCNQ,which achieves an excellent power factor of 671µW cm^(-1) K^(-2) at an optimal charge carrier concentration.Our findings not only clarify the critical role of molecular engineering in CTC-based TE materials but also provide valuable guidance for developing high-efficiency organic TE materials with versatile practical applications. 展开更多
关键词 Charge-transfer complexes Organic thermoelectric Power factor First-principles calculations Structure-property relationships
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The PbrMADS1-PbrMYB169 complex has uniquely emerged to regulate lignification of stone cells in pear
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作者 Yongsong Xue Shulin Chen +6 位作者 Yingyu Hao Meng Shan Pengfei Zheng Runze Wang Mingyue Zhang Jun Wu Cheng Xue 《Journal of Integrative Plant Biology》 2026年第1期239-256,共18页
Lignified stone cells are a unique feature of pear fruit,significantly affecting fruit texture.Even though some research efforts have already been made,the stone cell formation mechanism is complex,with many aspects y... Lignified stone cells are a unique feature of pear fruit,significantly affecting fruit texture.Even though some research efforts have already been made,the stone cell formation mechanism is complex,with many aspects yet to be elucidated.Here,through a genome-wide association analysis of stone cell traits,we identified PbrMADS1,a member of the SEPALLATA3(SEP3)subfamily,as a candidate gene specifically expressed in stone cells during early fruit development.Functional studies confirmed that PbrMADS1 promotes stone cell formation;however,it does not directly activate lignin-related genes.Instead,Pbr MADS1 interacts with PbrMYB169,enhancing PbrMYB169's binding to AC elements and amplifying downstream gene activation.Notably,homologous MADS1 and MYB169 proteins from closely related species such as apple and loquat do not form a similar complex.Sequence analysis revealed that the protein sequence of PbrMADS1 contains methionine(M)at the 63rdamino acid position,while apple and loquat homologs carry threonine(T)at the same site.Substituting M with T(PbrMADS1^(M63T))weakened its interaction with Pbr MYB169 and impaired its function in regulating stone cell formation.This study offers new insights into MADS gene-mediated stone cell formation and highlights functional divergence within the SEP3 subfamily among apple tribe species of the Rosaceae family. 展开更多
关键词 functional divergence PbrMADS1-PbrMYB169 complex PEAR stone cells
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