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Intercalation-enabled bonding design for La_(2)Bi_(4)Cu_(2)Se_(2)Te_(2)O_(6)with high thermoelectric performance
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作者 Pengfei Zhang Yufei Meng +7 位作者 Shulin Bai Da Wan Peng Ai Zhiwei Zhang Yunzhuo Zhang Zhanpeng Xu Yujie Bao Shuwei Tang 《Journal of Energy Chemistry》 2026年第1期243-250,I0006,共9页
Thermoelectric (TE) materials enable precise, noiseless, and moving-part-free waste heat recovery and solid-state refrigeration through the Seebeck and Peltier effects [1–3]. The efficiency of TE materials is typical... Thermoelectric (TE) materials enable precise, noiseless, and moving-part-free waste heat recovery and solid-state refrigeration through the Seebeck and Peltier effects [1–3]. The efficiency of TE materials is typically evaluated by a dimensionless figure of merit (ZT = S2σT/(κe+ κl)), which depends on the delicate interplay among the electrical conductivity (σ), Seebeck coefficient (S), lattice thermal conductivity (κl), and electronic thermal conductivity (κe) [4]. 展开更多
关键词 intercalation strategy Interlayer static insulation Two-channel model Thermoelectric materials
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Nanoreactor-Structured Defective MoS_(2):Suppressing Intercalation-Induced Phase Transitions and Enhancing Reversibility for Potassium-Ion Batteries
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作者 Chunrong Ma Cyrus Koroni +3 位作者 Jiacheng Hu Ji Qian Guangshuai Han Hui Xiong 《Nano-Micro Letters》 2026年第4期771-786,共16页
Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible s... Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering. 展开更多
关键词 Potassium ion batteries Phase transitions Structure reversibility Intercalated heterostructure Defect engineering
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Sr^(2+)and choline chloride cointercalation in V_(2)O_(5) for aqueous zinc-ion batteries
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作者 Shiyuan Chen Yongchun Zhu 《中国科学技术大学学报》 北大核心 2025年第3期20-26,19,I0001,共9页
V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve th... V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries. 展开更多
关键词 aqueous Zn-ion batteries vanadium oxides ion intercalation
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Dynamic hydrogen intercalation catalysis
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作者 Hao Zhang Xiaosong Xiong +1 位作者 Tao Wang Yuping Wu 《Chinese Journal of Catalysis》 2025年第7期1-3,共3页
Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalyti... Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalytic reaction efficiency and selectivity[1–3].This technique has achieved significant progress in areas such as electrocatalysis,catalytic cracking,and energy conversion,especially in reactions like hydrogen generation,oxygen reduction,nitrogen reduction,and carbon dioxide reduction[4–6].Intercalation catalysis can enhance catalyst activity and selectivity,but challenges remain regarding stability,reusability,and industrial application.Future research will focus on developing new intercalation materials,optimizing catalyst design,and exploring their potential applications in complex environments[7]. 展开更多
关键词 metal ionsmoleculesor carbon dioxide adjust their electronic structure surface propertiesthereby electrocatalysiscatalytic crackingand intercalation catalysis energy conversionespecially dynamic hydrogen intercalation ionic liquids
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Hard Lewis acid CeO_(2)and Cl^(-)intercalation induce OH-enriched and strong Cl^(-)repulsive microenvironment for ultra-stable industrialized seawater electrolysis
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作者 Xueran Shen Wenchao Liu +8 位作者 Mingzhe Liu Haibo Jin Yuefeng Su Ning Li Jingbo Li Zhiyong Xiong Caihong Feng Jianxin Kang Lin Guo 《Journal of Energy Chemistry》 2025年第9期567-576,I0015,共11页
Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chlori... Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chloride oxidation reactions make oxygen evolution reaction(OER)in seawater extremely challenging.Herein,the low-cost and scalable CoFe layered double hydroxides with Cl^(-)intercalation and decorated with Ce(OH)_(3)(named as CoFe-Cl^(-)/Ce(OH)_(3))catalyst is synthesized via rapid electrodeposition under ambient conditions,which is quickly reconstructed into a CeO_(2)decorated and Cl^(-)intercalated CoFeOOH(CoFeOOH-Cl^(-)/CeO_(2))during OER.Theoretical investigation reveals that Cl^(-)intercalation weakens the adsorption ability of Cl^(-)on Co/Fe atoms and hinders unfavorable coupling with chloride,thereby preventing the chlorine corrosion process and enhancing catalytic stability and activity.The CeO_(2)with hard Lewis acidity preferentially binds to OH-with harder Lewis base to ensure the OH-rich microenvironment around catalyst even under high current operating conditions,thus further enhancing stability and improving OER activity.The functionalized CoFe-Cl^(-)/Ce(OH)_(3)delivers 1000 mA cm^(-2)current density at only 329 mV overpotential with excellent stability for 1000 h under alkaline seawater.Electrochemical experiments elucidate the OER catalytic mechanism in which CeO_(2)serves as a co-catalyst for enriching OH-and CoFeOOH-Cl^(-)is the active species.Our work is a substantial step towards achieving massive and sustainable production of hydrogen fuel from immense seawater. 展开更多
关键词 Seawater oxidation CoFe-LDH ELECTROCATALYSIS Lewis acidity Chloride intercalation
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Formamidine intercalation to broaden photoresponsive range in alternating-cations-interlayered hybrid perovskite
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作者 Yaru Geng Ruiqing Li +6 位作者 Tingting Zhu Xinling Li Qianwen Guan Huang Ye Peng Wang Junlin Li Junhua Luo 《Chinese Chemical Letters》 2025年第8期538-541,共4页
Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an imp... Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an important parameter for photodetection,the photoresponsive range of 2D OIHPs is usually modulated by finite metal-halide combinations,constraining their further development.The emerging aromatic amine-based alternating-cations-interlayered(A-ACI)hybrid perovskites that exhibit excellent charge transport and additional interlayered structural designability,provide an extra solution for achieving ideal photoresponsive range.Herein,for the first time,the photoresponsive range is successfully broadened in A-ACI hybrid perovskites(NMA)_(4)(FA)_(2)Pb_(3)Br_(12)(2)remolding from(NMA)_(4)(MA)_(2)Pb_(3)Br_(12)(1)(NMA=N-methylbenzylaminium,FA=formamidinium and MA=methylammonium).Particularly,1 and 2adopt an unprecedented configuration that NMA and MA/FA are alternately arranged in the interlayer in a 4:2 manner.Importantly,2 exhibits a narrower bandgap than 1,which can be ascribed to the lowlying conduct band composed of intercalation FAπ*orbitals.Meanwhile,2 possesses a shorter interlayer distance and flatter inorganic skeleton,synergistically facilitating the wider photo-absorption range and further endowing a broadening photoresponsive range(70 nm).This research not only enriches the perovskite family but also provides insights into structure-property relationships. 展开更多
关键词 Hybrid perovskites Alternating-cations-interlayered Formamidine intercalation Broadening photoresponsive range Photodetection
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AI-driven accelerated discovery of intercalation-type cathode materials for magnesium batteries
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作者 Wenjie Chen Zichang Lin +2 位作者 Xinxin Zhang Hao Zhou Yuegang Zhang 《Journal of Energy Chemistry》 2025年第9期40-46,I0003,共8页
Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performa... Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performance Mg cathode materials.Utilizing the common characteristics of various ionic intercalation-type electrodes,we design and train a Crystal Graph Convolutional Neural Network model that can accurately predict electrode voltages for various ions with mean absolute errors(MAE)between0.25 and 0.33 V.By deploying the trained model to stable Mg compounds from Materials Project and GNoME AI dataset,we identify 160 high voltage structures out of 15,308 candidates with voltages above3.0 V and volumetric capacity over 800 mA h/cm^(3).We further train a precise NequIP model to facilitate accurate and rapid simulations of Mg ionic conductivity.From the 160 high voltage structures,the machine learning molecular dynamics simulations have selected 23 cathode materials with both high energy density and high ionic conductivity.This Al-driven workflow dramatically boosts the efficiency and precision of material discovery for multivalent ion batteries,paving the way for advanced Mg battery development. 展开更多
关键词 Magnesium-ion batteries Interpretable machine learning AI-driven workflow Material screening intercalation cathode materials
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Unlocking uniform and stable SEI formation through optimizing oxygen vacancies in SnO_(2) enables reversible lithium intercalation
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作者 Pinxian Jiang Yuxin Fan +4 位作者 Mohamed Ait Tamerd Jianlong Cong Zhengkun Xie Menghao Yang Jiwei Ma 《Journal of Materials Science & Technology》 2025年第29期202-208,共7页
Despite its high capacity behavior as the anode for lithium-ion batteries (LIBs), SnO_(2) suffers the poorelectronic conductivity and high volume expansion, which lead to poor cycling stability and rate capability. In... Despite its high capacity behavior as the anode for lithium-ion batteries (LIBs), SnO_(2) suffers the poorelectronic conductivity and high volume expansion, which lead to poor cycling stability and rate capability. In this study, we employ defect engineering to design SnO_(2−x)(x = 0, 0.12, 0.2, and 0.3) nanoparticleswith varied oxygen vacancies. Notably, the SnO1.80 electrode with 20 % oxygen vacancies exhibits excellent electrochemical performance. Advanced physical characterizations combined with density functionaltheory (DFT) simulations demonstrate that the improved electrochemical performance can be attributedto the formation of a stable, uniform, and LiF-rich solid-electrolyte interface (SEI) layer through the optimization of oxygen vacancies. This study shows novel insights into the application of defect engineeringwithin oxides for the rational design of the uniform surface layer toward high-energy-density LIBs. 展开更多
关键词 SnO_(2) Oxygen vacancy SEI Reversible intercalation Li-ion batteries
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Manipulating the magnetic properties of MnBi_(2)Te_(4)through electrochemical organic molecule intercalation
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作者 Yu Du Heng Zhang +7 位作者 Fuwei Zhou Tianqi Wang Jiajun Li Wuyi Qi Yiying Zhang Yefan Yu Fucong Fei Fengqi Song 《Chinese Physics B》 2025年第8期427-433,共7页
MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties en... MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties enables the observation of exotic quantum phenomena such as the quantum anomalous Hall effect,axion insulator states,and Majorana fermions.While the intercalation of Bi_(2)Te_(3)can tune its magnetism,synthesizing pure-phase MnBi_(2)Te_(4)with uniform Bi_(2)Te_(3)intercalation remains challenging,and the fixed interlayer spacing of Bi_(2)Te_(3)limits magnetic coupling tunability.Here,we utilize electrochemical organic molecule intercalation to expand the van der Waals gap of MnBi_(2)Te_(4)and modulate its magnetic properties.Through x-ray diffraction(XRD)characterizations,we confirm that the interlayer spacing of MnBi_(2)Te_(4)is expanded from 13.6°A to 30.5°A and 61.0°A by intercalating quaternary ammonium cations(THA^(+)and CTA^(+)),respectively.The THA-MnBi_(2)Te_(4)exhibits dual complex magnetic behavior,combining AFM ordering with a Neel temperature(T_(N))of 12 K and a small ferromagnetic hysteresis loop at 2 K.The CTA-MnBi_(2)Te_(4)shows robust ferromagnetism,with a Curie point(T_(C))of 15 K,similar to that of the MnBi_(2)Te_(4)monolayer.These results demonstrate that remarkable changes in the magnetic properties of MnBi_(2)Te_(4)can be achieved via electrochemical intercalation,providing new insights into manipulating magnetism in layered magnetic materials. 展开更多
关键词 topological insulators electrochemical intercalation magnetism tuning van der Waals magnetic materials
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Lithium-intercalation-induced structural evolution and superconductivity modulation in 2H-Li_(x)TaSe_(2)
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作者 Lijia Zhou Xiangjiang Dong +2 位作者 Qiang Li Xiaojun Kuang Xianran Xing 《Chinese Physics B》 2025年第11期514-520,共7页
We systematically investigated the structural and superconducting properties of polycrystalline 2H-Li_(x)TaSe_(2)(0.1≤x≤1.0)synthesized via a high-temperature solid-state reaction.Lithium(Li)intercalation induces an... We systematically investigated the structural and superconducting properties of polycrystalline 2H-Li_(x)TaSe_(2)(0.1≤x≤1.0)synthesized via a high-temperature solid-state reaction.Lithium(Li)intercalation induces an expansion along the c-axis and intralayer distortions within the Ta-Se coordination network.The superconducting transition temperature(T_(c))is increased to 2.95 K at x=0.1 driven by the synergistic enhancement of the electronic density of states at the Fermi level,N(EF),and strengthened electron-phonon coupling.With further Li doping,although N(EF)continues to increase,lattice stiffening and pronounced distortions in the Ta-Se coordination polyhedra weaken the electron-phonon interaction,ultimately suppressing superconductivity.These findings highlight the critical role of intralayer structural modulation in governing structure-tunable superconductivity in layered materials. 展开更多
关键词 SUPERCONDUCTIVITY Li intercalation local structural distortion
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Tungsten carbide-reduced graphene oxide intercalation compound as co-catalyst for methanol oxidation 被引量:3
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作者 施梅勤 章文天 +2 位作者 李影影 褚有群 马淳安 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1851-1859,共9页
Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The met... Highly dispersed tungsten carbide(WC) nanoparticles(NPs) sandwiched between few-layer reduced graphene oxide(RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent.The metatungstate ion,[H2W(12)O(40)]^6-,is assembled on thiourea-modified graphene oxide(GO) by an impregnation method.The WC NPs,with a mean diameter of 1.5 nm,are obtained through a process whereby ammonium metatungstate first turns to WS2,which then forms an intercalation compound with RGO before growing,in situ,to WC NPs.The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method.The intimate contacts between Pt,WC,and RGO are confirmed by X-ray diffraction,scanning electron microscope,transmission electron microscope,and Raman spectroscopy.For methanol oxidation,the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m^2/g Pt and a peak current density of1364.7 mA/mg Pt,which are,respectively,3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst(67.2 m^2/g Pt,286.0 mA/mg Pt).The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping,chronoamperometry,and accelerated durability testing.Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C,as a result of its intercalated structure and synergistic effect,less Pt will be required for the same performance,which in turn will reduce the cost of the fuel cell.The present method is facile,efficient,and scalable for mass production of the nanomaterials. 展开更多
关键词 Tungsten carbide-reduced graphene oxide intercalation compound THIOUREA ANCHORING Methanol oxidation
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典型腮腺闰管腺瘤1例
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作者 孙永红 李增佑 +3 位作者 金鑫瑶 张翠 杨敏 王勇 《临床与实验病理学杂志》 北大核心 2026年第1期135-137,共3页
闰管腺瘤(intercalated duct adenoma,IDA)是第5版WHO涎腺肿瘤分类中新增的肿瘤类型,临床罕见报道。组织学上肿瘤主要由闰管状小管构成,小管由两种细胞构成,位于腔面的增生的立方形导管细胞和外周的肌上皮细胞。肌上皮标志物可以显示导... 闰管腺瘤(intercalated duct adenoma,IDA)是第5版WHO涎腺肿瘤分类中新增的肿瘤类型,临床罕见报道。组织学上肿瘤主要由闰管状小管构成,小管由两种细胞构成,位于腔面的增生的立方形导管细胞和外周的肌上皮细胞。肌上皮标志物可以显示导管周围肌上皮细胞,导管细胞显示CK7弥漫阳性,多数病例S-100阳性,溶菌酶和雌激素受体局灶阳性,腺泡和闰管的特异性标志物SOX10弥漫阳性。本例IDA需要与纹管腺瘤和基底细胞腺瘤相鉴别。 展开更多
关键词 闰管腺瘤 腮腺 鉴别诊断 病例报道
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Reducing bentonite usage in iron ore pelletization through synergistic modification with mechanical force and DMSO:Effects and mechanisms
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作者 Yinrui Dong Yongbin Yang +4 位作者 Lin Wang Qianqian Duan Qian Li Yan Zhang Tao Jiang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期177-190,共14页
Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pell... Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders. 展开更多
关键词 PELLETS bentonite modification mechanical force dimethyl sulfoxide organic intercalation
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Calf Thymus DNA Intercalation by Anionic Ru(Ⅲ) Complexes Containing Tridentate Schiff Bases Derived from 5-X-Substituted Salicyladehyde and 2-Aminophenol
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作者 Emlra Kahrowc Adnan Zahirovic Emir Turkusic 《Journal of Chemistry and Chemical Engineering》 2014年第4期335-343,共9页
Sodium bis[N-2-oxyphenyl-5-substituted-salicylideneiminato-ONO]ruthenate(Ⅲ) hemitriethylamine compounds of general formula Na[Ru(N-R-5-X-salim)2]'0.5Et3N, where, R = C6H40, X = El, Br, NO2, salim = salicylidenei... Sodium bis[N-2-oxyphenyl-5-substituted-salicylideneiminato-ONO]ruthenate(Ⅲ) hemitriethylamine compounds of general formula Na[Ru(N-R-5-X-salim)2]'0.5Et3N, where, R = C6H40, X = El, Br, NO2, salim = salicylideneiminato, Et3N triethylamine, were synthesized and characterized on the basis of elemental analysis, MALDI-TOF (matrix-assisted laser desorption/ionization/time-of-flight) mass spectra, IH NMR (nuclear magnetic resonance), electronic spectra and cyclic voltammograms. Ru(Ⅲ) is chelated with two O2N anionic tridentate Schiff bases derived from 5-X-salicyladehyde and 2-aminophenol. Spectroscopic titrations of the Ru(Ⅲ) compounds with CT DNA (calf thymus DNA) in the LMCT (ligand metal charge transfer) region have shown moderate intercalation properties of compounds with binding constants KD = 2.06-3.85 × 104 Ml. Electrochemical evidence of intercalative mode of binding is based on the decrease of current and shift of anodic and cathodic peaks towards higher values of potential with IxL-increment of CT DNA in Ru(Ⅲ) compound solution. 展开更多
关键词 RUTHENIUM Schiff bases salicylideneimine CT DNA intercalation.
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基于不对称Aldol反应的插层磁性水滑石的制备及催化研究
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作者 唐慧嘉 葛源怡 +2 位作者 吴紫薇 李龙波 张慧恩 《广东化工》 2026年第4期5-10,共6页
针对水滑石催化Aldol缩合反应时回收利用率低、产物手性特异性不足的问题,本研究制备了磁性水滑石(LDH-M)及其脯氨酸插层复合材料(LDH-M-Pro),并用于催化对硝基苯甲醛与丙酮的Aldol缩合反应,通过XRD、SEM、FT-IR等手段对其进行表征。结... 针对水滑石催化Aldol缩合反应时回收利用率低、产物手性特异性不足的问题,本研究制备了磁性水滑石(LDH-M)及其脯氨酸插层复合材料(LDH-M-Pro),并用于催化对硝基苯甲醛与丙酮的Aldol缩合反应,通过XRD、SEM、FT-IR等手段对其进行表征。结果显示,两种磁性水滑石晶型、形貌及催化性能优良,脯氨酸插入会增加层间距但不改变结构与形貌。在对硝基苯甲醛1.00 g、催化剂0.05 g、50℃反应2.5 h的条件下,LDH-M转化率96.4%(产率83.3%),LDH-M-Pro转化率97.9%(产率90.9%),且后者提升了产物手性特异性。本实验解决了水滑石催化剂回收难题,其循环使用5次仍保持85.0%以上初始活性,还增强了反应产物手性特异性,实现ee值>50.0%的手性产物合成,为新型手性催化剂体系发展提供理论与实践参考。 展开更多
关键词 层状双金属氢氧化物 磁性固体碱 Aldol缩合 手性催化 脯氨酸插层
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Lithium intercalation/de-intercalation behavior of a composite Sn/C thin film fabricated by magnetron sputtering 被引量:8
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作者 ZHAO Lingzhi HU Shejun +2 位作者 LI Weishan LI Liming HOU Xianhua 《Rare Metals》 SCIE EI CAS CSCD 2008年第5期507-512,共6页
A tin film of 320 nm in thickness on Cu foil and its composite film with graphite of-50 nm in thickness on it were fabricated by magnetron sputtering. The surface morphology, composition, surface distributions of allo... A tin film of 320 nm in thickness on Cu foil and its composite film with graphite of-50 nm in thickness on it were fabricated by magnetron sputtering. The surface morphology, composition, surface distributions of alloy elements, and lithium intercalation/de-intercalation behaviors of the fabricated films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe microanalyzer (EPMA), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectrometry (ICP), cyclic voltammetry (CV), and galvanostatic charge/discharge (GC) measurements. It is found that the lithium intercalation/de-intercalation behavior of the Sn film can be significantly improved by its composite with graphite. With cycling, the discharge capacity of the Sn film without composite changes from 570 mAh/g of the 2nd cycle to 270 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 90% and 95%. Nevertheless, the discharge capacity of the composite Sn/C film changes from 575 mAh/g of the 2nd cycle to 515 mAh/g of the 20th cycle, and its efficiency for the discharge and charge is between 95% and 100%. The performance improvement of tin by its composite with graphite is ascribed to the retardation of the bulk tin cracking from volume change during lithium intercalation and de-intercalation, which leads to the pulverization of tin. 展开更多
关键词 lithium-ion battery ANODE magnetron sputtering composite film lithium intercalation/de-intercalation
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Physical Blocking Neural Tube Closure Affects Radial Intercalation and Neural Crest Midline-directed Migration in Xenopus Dorsal Explants
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作者 石宇 赵树华 毛炳宇 《Zoological Research》 CAS CSCD 北大核心 2009年第6期639-644,共6页
Neural tube defects (NTDs) are severe congenital malformation diseases, which occur in 1 out of 1000 births in human. In Xenopus, several tissue movements are involved in the neural tube closure process. Immediately... Neural tube defects (NTDs) are severe congenital malformation diseases, which occur in 1 out of 1000 births in human. In Xenopus, several tissue movements are involved in the neural tube closure process. Immediately after the neural tube fusion, the neural crest cells get monopolar protrusion toward dorsal midline and migrate to form the roof of the neural tube. At the same time, radial intercalation takes place from the ventral neural tube and forces it to be single-layered. Here, we physically block the neural tube closure to test the cell movements and the following patterning in Xenopus laevis explants. The results show that the single-layered neural tube fails to form and the neural crest cells remain at the lateral regions in the explants with NTDs. However, the patterning of the neural tube is not affected as indicated by the normal expression of the preneural genes. These results indicate a requirement of the neural tube fusion for the radial intercalation and the dorsal midline directed neural crest migration, but not for the dorsal-ventral patterning of the neural tube. 展开更多
关键词 Xenopus laevis Neural tube defect Neural tube closure Neural crest Morghogenesis intercalation Dorsoventral patterning
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Preparation and Properties of Phenolic Resin/Montmorillonite Intercalation Nanocomposites 被引量:6
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作者 余剑英 WEILian-qi CAOXian-kum 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第4期64-67,共4页
Phenolic resin/montmorillonite intercalation composites were prepared by using the methods of pressing intercalation and melt intercalation.Properties and structure of the composites were investigated by using XRD,TG ... Phenolic resin/montmorillonite intercalation composites were prepared by using the methods of pressing intercalation and melt intercalation.Properties and structure of the composites were investigated by using XRD,TG and test of softening point.It is indicated that both the pressing intercalation and melt intercalation can be used to prepare the phenolic resin/organo-montmorillonite intercalation nanocomposites.Compared with phenolic resin,the intercalation nanocomposites have better heat-resistance,higher decomposition temperatures and less thermal weight-loss.However,these two intercalation methods have different effects on the softening point of the intercalation nanocomposites.Pressing intercalation almost does not affect the softening point of the intercalation nanocomposites,while melt intercalation significantly increases the softening point of the intercalation nanocomposites, probably due to the chemical actions happening in the process of melt intercalation. 展开更多
关键词 MONTMORILLONITE phenolic resin pressing intercalation melt intercalation NANOCOMPOSITE
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K+alkalization promoted Ca2+intercalation in V2CTx MXene for enhanced Li storage 被引量:8
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作者 Ming Lu Yaopeng Zhang +5 位作者 Junnan Chen Wenjuan Han Wei Zhang Haibo Li Xia Zhang Bingsen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第10期358-364,共7页
Although MXenes is highly attractive as anode materials of lithium ion batteries,it sets a bottleneck for higher capacity of the V2CTxMXene due to the limited interlayer space and the derived surface terminations.Here... Although MXenes is highly attractive as anode materials of lithium ion batteries,it sets a bottleneck for higher capacity of the V2CTxMXene due to the limited interlayer space and the derived surface terminations.Herein,the cation intercalation and ion-exchange were well employed to achieve a K+and Ca2+intercalated V2CTxMXene.A larger interlayer distance and low F surface terminations were thereof obtained,which accelerates the ion transport and promotes the delicate surface of V2CTx MXene.As a result,a package of enhanced capacity,rate performance and cyclability can be achieved.Furthermore,the ion exchange approach can be extended to other 2 D layered materials,and both the interlayer control and the surface modification will be achieved. 展开更多
关键词 V2CTx MXenes Calcium ion Interlayer distance intercalation Lithium storage
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STUDY ON INTERCALATION MECHANISM OF GELATIN/MMT NANOCOMPOSITE
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作者 李萍 郑俊萍 姚康德 《Transactions of Tianjin University》 EI CAS 2001年第4期294-296,共3页
A gelatin/MMT nanocomposite was prepared in an aqueous solution and investigated by XRD,FTIR and 13 C NMR,and then the intercalation mechanism was discussed.The result of XRD indicated that the gelatin molecule... A gelatin/MMT nanocomposite was prepared in an aqueous solution and investigated by XRD,FTIR and 13 C NMR,and then the intercalation mechanism was discussed.The result of XRD indicated that the gelatin molecule had already inserted into the interlayer of MMT,and the intercalation or exfoliation structure had been achieved.The result of 13 C NMR demonstrated that the ions interaction between gelatin and MMT was attributed to the driving force for intercalation.In order to confirm the role of -COO - of gelatin in the combination with MMT,lauric sodium was brought in as a model to react with MMT,and was characterized by XRD and FTIR,the result proved that there existed a kind of strong interaction between -COO - and ions of MMT. 展开更多
关键词 GELATIN MMT NANOCOMPOSITE intercalation mechanism
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