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Synthesis of a novel carbon microsphere with multi-cavity mesoporous structure for CO_(2) adsorption
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作者 Li Liu Qunyan Li +3 位作者 Qi Wei Yan Mei Wenjuan Chen Zuoren Nie 《Journal of Environmental Sciences》 2026年第1期199-209,共11页
Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspher... Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption. 展开更多
关键词 Porous carbon CO_(2)adsorption Multi-cavity structure Carbon sphere
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Electrochemical phase reconstruction of biomimetic MnO_(2)structure to enhance sodium-ion storage kinetics in aqueous systems
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作者 Weijie Zheng Jingzhou Ling +7 位作者 Shiru Li Tian Wen Zhibiao Cui Dong Shu Xiuhua Li Honghong Cheng Fan Zhang Tao Meng 《Journal of Energy Chemistry》 2026年第1期29-38,I0003,共11页
The application of conventional manganese dioxide(MnO_(2))materials in sodium-ion supercapacitors(Na-SCs)is considerably limited by their low conductivity and structural instability.Biomimetic morphology engineering c... The application of conventional manganese dioxide(MnO_(2))materials in sodium-ion supercapacitors(Na-SCs)is considerably limited by their low conductivity and structural instability.Biomimetic morphology engineering can optimize the electrochemical performance of MnO_(2).Here,based on the metal-organic frameworks(MOFs)-derived method and electrochemical reconstruction,a coral-like MnO_(2)structure integrated with a functional nitrogen-doped carbon(NC)coating is designed for Na-SC application.The bioinspired coral-like structure captures numerous electrolyte ions and increases the Na+concentration on the electrode surface,which is beneficial for optimizing the Na+transport pathway and accelerating the electrode reaction kinetics.Moreover,the coral-like crosslinked structure effectively enhances the mechanical properties,enabling the maintenance of the structure of MnO_(2)-based electrodes during long-term operation.Furthermore,in/ex-situ characterizations are performed to elucidate the mechanism of lattice transformation during electrochemical phase reconstruction.Additionally,the theoretical calculation and simulation results reveal the ion/electron dynamics in the fabricated electrode.The prepared electrode demonstrates excellent capacitance storage ability(340.7 F g^(−1)at 0.5 A g^(−1))and cycling stability(85.1%capacitance retention after 10,000 cycles).The assembled hybrid device exhibits exceptional life-span(82.0%capacitance retention after 10,000 cycles)and exceptional energy density(36.5 Wh kg^(−1)).This study provides a reliable biomimetic morphology design strategy for MnO_(2)cathodes,paving the way for the fabrication of high-performance Na-SCs. 展开更多
关键词 Biomimetic structure Coral-like Mno_(2) Electrochemical phase reconstruction Nitrogen-doped carbon Sodium-ion supercapacitors
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Cu-ZnO催化CO_(2)加氢制甲醇反应构效关系研究进展
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作者 魏新煜 苏暐光 +3 位作者 白永辉 宋旭东 吕鹏 于广锁 《石油学报(石油加工)》 北大核心 2026年第1期107-117,共11页
CO_(2)转化为甲醇可缓解温室效应并满足能源需求,而高效转化的关键在于催化剂设计。Cu-ZnO催化剂具有高转化率、良好甲醇选择性、低成本和易调控组成等优点,成为CO_(2)加氢制甲醇的主流催化体系。从甲酸盐路径和逆水煤气变换路径2种反... CO_(2)转化为甲醇可缓解温室效应并满足能源需求,而高效转化的关键在于催化剂设计。Cu-ZnO催化剂具有高转化率、良好甲醇选择性、低成本和易调控组成等优点,成为CO_(2)加氢制甲醇的主流催化体系。从甲酸盐路径和逆水煤气变换路径2种反应路径综述了不同Cu-ZnO催化剂上CO_(2)加氢制甲醇的研究进展,并对加氢反应中所涉及的活性位点及构效关系,如金属价态、界面相互作用、尺寸效应与限域效应等方面进行分析探讨。总结了近年来利用金属有机框架、分子筛、层状双金属氢氧化物和类水滑石化合物等材料制备的新型结构Cu-ZnO、Cu-ZnO-M_(x)O_(y)复合三元催化剂的甲醇生成活性。Cu基催化剂的活性和稳定性仍需提升,且反应中的关键中间体尚不明确,未来Cu-ZnO催化剂的研究应聚焦于原位分析与机器学习相结合,优化催化剂尺寸、形状及载体性能,整合酸碱与氧化还原功能,明确CO_(2)转化机理并提高催化效率。 展开更多
关键词 Cu-Zno催化剂 CO_(2)加氢制甲醇 反应机理 活性位点 构效关系
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CeMnO_(x)@TiO_(2)核壳催化剂的制备及其性能研究
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作者 张荣海 王建海 沈岳松 《工业催化》 2026年第1期31-37,共7页
通过控制水解法制备了CeMnO_(x)@TiO_(2)核壳催化剂,并通过调节钛酸四丁酯的水解时间实现了不同厚度的TiO_(2)壳层的包裹。利用XRD、SEM和TEM等表征手段,对催化剂的物相及其微观形貌特征进行了分析。H_(2)-TPR和NH_(3)-TPD实验结果表明,... 通过控制水解法制备了CeMnO_(x)@TiO_(2)核壳催化剂,并通过调节钛酸四丁酯的水解时间实现了不同厚度的TiO_(2)壳层的包裹。利用XRD、SEM和TEM等表征手段,对催化剂的物相及其微观形貌特征进行了分析。H_(2)-TPR和NH_(3)-TPD实验结果表明,TiO_(2)壳层的引入一定程度上会降低催化剂的氧化还原能力,但显著增强了其表面酸性。催化剂的性能测试表明,适量的TiO_(2)壳层能够在不损害催化剂低温脱硝活性的同时扩宽脱硝温度窗口并提高N_(2)选择性,而过厚的TiO_(2)壳层则会抑制反应传质过程,导致催化活性下降。该研究结果为构筑稳定高效和高N_(2)选择性的低温SCR脱硝催化剂提供重要的理论和技术支撑。 展开更多
关键词 催化剂工程 CeMno_(x)@TiO_(2) 核壳结构 低温脱硝 表面酸性 N_(2)选择性
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Genetic diversity and population structure of the Fujian oyster Crassostrea angulata revealed by mitochondrial COI gene and nuclear gene ITS2 sequences
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作者 Shiqi YU Ziqiang HAN Huayong QUE 《Journal of Oceanology and Limnology》 2026年第1期419-432,共14页
The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai... The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata. 展开更多
关键词 Crassostrea angulata genetic diversity population structure mitochondrial COⅠgene nuclear gene ITS2 sequence
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Molecular dynamics investigation on structure and crystallization characteristics of MgO-CaO-Al_(2)O_(3)-SiO_(2) oxides
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作者 Zheng-Tao Li Wen Yang +4 位作者 Li-Feng Zhang Wu-San Liang Guo-Li Du Yong-Wu Li Yao Zeng 《Journal of Iron and Steel Research International》 2026年第1期469-481,共13页
MgO has been shown to facilitate the precipitation of MgO-rich crystalline phases within the MgO-CaO-Al_(2)O_(3)-SiO_(2)(MCAS)glassy inclusion system,which possesses a high liquidus temperature and a significant Young... MgO has been shown to facilitate the precipitation of MgO-rich crystalline phases within the MgO-CaO-Al_(2)O_(3)-SiO_(2)(MCAS)glassy inclusion system,which possesses a high liquidus temperature and a significant Young’s modulus.The underlying linkage between the structural evolution and the crystallization characteristics of the MCAS system was systematically investigated using molecular dynamics simulation and thermodynamic calculation.The results revealed that Mg^(2+) ions played a dual role,constructing networks through the formation of tricluster oxygens while consuming bridging oxygens(BOs)in a mechanism similar to Ca^(2+) ions.However,despite this dual role,the network connectivity was still decreased with the increase in MgO/(MgO+Al_(2)O_(3))(M/(M+A))and CaO/(CaO+SiO_(2))(C/(C+S))ratios,primarily due to the reduction in BOs.This microscopic structural evolution resulted in a reduction in viscosity and an enhancement of crystallization ability.Furthermore,the remarkable diffusion capability of Mg^(2+) ions,coupled with the increased proportion of 6-coordinated Mg^(2+)ions,unveiled the mechanism underlying the precipitation of MgSiO_(3) and Mg_(2)SiO_(4) crystals,which exhibited high Young’s moduli of 165.23 and 196.67 GPa,respectively.To prevent the precipitation of MgO-rich crystalline phases,it was crucial to maintain the M/(M+A)ratio below 0.42 and the C/(C+S)ratio below 0.16 within the MCAS system. 展开更多
关键词 MgO-CaO-Al_(2)O_(3)-SiO_(2)system Molecular dynamics Thermodynamic calculation Structural evolution Crystallization characteristic Young’s modulus
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In situ directly grown carboxylated UiO-66-infused separator as a comprehensive regulator of Zn solvation structure enabling dendrite-and corrosion-free Zn metal anode
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作者 Jung Bin Park Bo Keun Park +4 位作者 Ji Woo Han Sung Joon Park Seungyeop Kang Dong-Joo Yoo Ki Jae Kim 《Journal of Energy Chemistry》 2026年第1期634-644,I0014,共12页
Aqueous zinc ion batteries(AZIBs)are considered promising candidates owing to their inherent safety and low cost.However,the conventional glass fiber(GF)separator used in AZIBs suffers from poor physicochemical proper... Aqueous zinc ion batteries(AZIBs)are considered promising candidates owing to their inherent safety and low cost.However,the conventional glass fiber(GF)separator used in AZIBs suffers from poor physicochemical properties,leading to uncontrolled zinc(Zn)dendrite formation and undesirable side reactions.To address these limitations and enhance the electrochemical performance of AZIBs,a precisely designed functional separator is developed by incorporating UiO-66-(COOH)_(2)into a poly(vinylidene fluoride)(PVDF)framework(U-PVDF)via a direct in situ growth method.This approach enables uniform distribution of UiO-66-(COOH)_(2)both on the surface and within the PVDF backbone,without increasing separator thickness.Owing to the strong interaction between Zn^(2+)and the abundant carboxyl groups in UiO-66-(COOH)_(2),the U-PVDF separator regulates the Zn^(2+)solvation structure toward a contact ion pair-dominated structure by reducing coordinated water molecules,which effectively mitigates water-induced parasitic reactions and promotes compact Zn deposition.Consequently,a Zn/Zn symmetric cell employing the U-PVDF separator demonstrates superior cycling stability over 1500 cycles without internal short-circuiting at a current density of 6 mA cm^(−2)and an areal capacity of 2 mAh cm^(−2).Moreover,Zn/NaV_(3)O_(8)·xH_(2)O(NVO)cell with the U-PVDF separator exhibits markedly improved cyclability and rate performance compared with those using conventional GF separator. 展开更多
关键词 Zn metal anode Metal organic framework Zn2+solvation structure Zn dendrites Aqueous zinc ion battery Separator modification
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Self-powered horizontally structured n–n heterojunction photodetector based on Si–GaN/β-Ga_(2)O_(3) for UV detection
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作者 Muzi Li Maolin Zhang +3 位作者 Xueqiang Ji Shan Li Lili Yang Weihua Tang 《Chinese Physics B》 2026年第2期639-646,共8页
With the rapid advancement of optoelectronic technology,high-performance photodetectors are increasingly in demand in fields such as environmental monitoring,optical communication,and defense systems,where ultraviolet... With the rapid advancement of optoelectronic technology,high-performance photodetectors are increasingly in demand in fields such as environmental monitoring,optical communication,and defense systems,where ultraviolet detection is critical.However,conventional semiconductor materials suffer from limited UV-visible detection capabilities owing to their narrow bandgaps and high dark currents.To address these challenges,wide-bandgap semiconductors have emerged as promising alternatives.Here,we fabricated a horizontally structured n–n heterojunction photodetector by growingβ-Ga_(2)O_(3) on Si–GaN via plasma-enhanced chemical vapor deposition.The device exhibits a self-powered photocurrent of 3.5 nA at zero bias,enabled by the photovoltaic effect of the space charge region.Under 254-nm and 365-nm illumination,it exhibits rectification behavior,achieving a responsivity of 0.475 m A/W(0 V,220??W/cm~2 at 254 nm)and 257.6 mA/W(-5 V),respectively.Notably,the photodetector demonstrates a high photocurrent-to-dark current ratio of 10~5 under-5-V bias,highlighting its potential for self-powered and high-performance UV detection applications. 展开更多
关键词 Si–GaN/β-Ga_(2)O_(3) horizontally structured n–n heterojunction SELF-POWERED
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TDO2-Associated Tryptophan Metabolism Correlates with Impaired Tertiary Lymphoid Structure Maturation and Reduced B Cell Class Switching in Breast Cancer
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作者 Weiping Yang Wei Xiao +4 位作者 Wenhao Xu Lijun Ren Xian Li Junhua Yu Ronghua Wang 《Oncology Research》 2026年第3期667-690,共24页
Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryp... Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryptophan metabolism influences TLS maturation and B cell class switching in breast cancer.Methods:Bulk transcriptomic data from The Cancer Genome Atlas-Breast Invasive Carcinoma(TCGA-BRCA,n=1055)were analyzed using Gene Set Variation Analysis(GSVA)-based metabolic scoring,immune deconvolution,and TLS quantification.Single-cell RNA sequencing(scRNA-seq,n=26)and spatial transcriptomics(n=1)were applied to map TDO2 expression and TLS spatial organization.Validation was performed by immunohistochemistry(n=38)and multiplex immunofluorescence(n=12).Results:We identified that elevated tryptophan metabolism was predominantly enriched in the Luminal A subtype and delineates an immune-cold phenotype with less immunogenicity,associated with a distinct immune-dominant cellular microenvironment,particularly enriched in T and plasma cells.High expression of the tryptophan-metabolizing enzyme TDO2 was significantly enriched in TLS-low tumors and negatively correlated with TLS maturation signatures.Functional enrichment revealed suppressed B cell class switching and attenuated C-X-C motif chemokine ligand 9(CXCL9)expression in TLS-deficient tumors.Spatial transcriptomics and hotspot analysis demonstrated an inverse spatial correlation between TDO2 expression and TLS core components.Tumors with high tryptophan metabolism showed decreased cluster of differentiation 20(CD20)^(+)and CXCL9^(+)cell infiltration within TLS zones.Tumors with strong TDO2-kynurenine activity displayed impaired TLS organization and attenuated humoral immunity.Conditional spatial co-occurrence modeling confirmed reduced proximity between tryptophan metabolism hotspots and TLS-related immune features.Conclusion:In conclusion,our findings suggest that TDO2-associated tryptophan metabolism is linked to impaired TLS maturation and suppressed B cell class switching in breast cancer.Targeting the TDO2-kynurenine axis may represent a promising strategy to restore TLS formation and enhance immunotherapy responsiveness in breast cancer. 展开更多
关键词 Spatial transcriptomics KYNURENINE aryl hydrocarbon receptor(AhR) tryptophan 2 3-dioxygenase(TDO2) tertiary lymphoid structures(TLS) breast cancer tumor immune microenvironment
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A DFE2-SPCE Method for Multiscale Parametric Analysis of Heterogenous Piezoelectric Materials and Structures
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作者 Qingxiang Pei Fan Li +2 位作者 Ziheng Fei Haojie Lian Xiaohui Yuan 《Computers, Materials & Continua》 2025年第4期79-96,共18页
This paper employs the Direct Finite Element Squared(DFE2)method to develop Sparse Polynomial Chaos Expansions(SPCE)models for analyzing the electromechanical properties of multiscale piezoelectric structures.By incor... This paper employs the Direct Finite Element Squared(DFE2)method to develop Sparse Polynomial Chaos Expansions(SPCE)models for analyzing the electromechanical properties of multiscale piezoelectric structures.By incorporating variations in piezoelectric and elastic constants,the DFE2 method is utilized to simulate the statistical characteristics—such as expected values and standard deviations—of electromechanical properties,including Mises stress,maximum in-plane principal strain,electric potential gradient,and electric potential,under varying parameters.This approach achieves a balance between computational efficiency and accuracy.Different SPCE models are used to investigate the influence of piezoelectric and elastic constants on multiscale piezoelectric materials.Additionally,the multiscale parameterization study investigates how microscale material properties affect the macroscopic response of these structures and materials. 展开更多
关键词 DFE2 SPCE piezoelectric structures parameter analyses
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Construction of novel spherical ZnIn_(2)S_(4)-Ag-LaFeO_(3) heterostructures for enhancing photocatalytic efficiency
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作者 Dongsheng Jia Jiaxuan Pan +2 位作者 Dongliang Zhang Mitang Wang Ying Li 《Journal of Rare Earths》 2025年第2期295-303,I0003,共10页
Herein we report novel photocatalysts ZnIn_(2)S_(4)-Ag-LaFeO_(3) with the core-shell structured materials prepared by hydrothermal method.In order to improve the efficiency of photocatalytic degradation of pollutants,... Herein we report novel photocatalysts ZnIn_(2)S_(4)-Ag-LaFeO_(3) with the core-shell structured materials prepared by hydrothermal method.In order to improve the efficiency of photocatalytic degradation of pollutants,LaFeO_(3) was prepared by hydrothermal followed by calcination,and further Ag nanoparticle(NP)was loaded onto the spherical structure of LaFeO_(3) by photolysis of silver nitrate,and finally the spherical Znln_(2)S_(4)-Ag-LaFeO_(3) photocatalyst was prepared by hydrothermal method again.The structure and properties of the as-prepared materials were characterized by X-ray photoelectron spectroscopy,ultraviolet-visible absorption spectroscopy,X-ray diffraction,scanning electron microscopy and fluorescence spectra.The results show that the synthesized composite photocatalysts display a significant improvement in photocatalytic efficiency relative to the single LaFeO_(3) and ZnIn_(2)S_(4)and form a core-shell structure.Furthermore,the effect of the ratio of each component on the photocatalytic efficiency was investigated in detail,and it is discovered that at an Methylene Blue(MB)concentration of 0.219 mol/L,the degradation rate of MB is 95%at 120 min using 0.02 g of catalyst with an ideal ZnIn_(2)S_(4):Ag:LaFeO_(3)ratio of 10:0.5:1.The possible mechanisms to improve the photocatalytic efficiency were explored. 展开更多
关键词 ZnIn_(2)S_(4) LaFeO_(3) PHOTOCATALYSIS DEGRADATION Core-shell structure Rare earths
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Sulphur anion induced electronic structure regulation of RuO_(2) nanodots for efficient electrocatalytic overall water splitting
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作者 Xi-Zheng Fan Jing-Peng Hu +2 位作者 Xin Du Zhong-Yi Liu Xin-Zheng Yue 《Journal of Materials Science & Technology》 2025年第28期77-85,共9页
Developing bifunctional electrocatalysts with enhanced efficiency for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)remains a significant challenge.Herein,we constructed S-doped ultra-fine RuO... Developing bifunctional electrocatalysts with enhanced efficiency for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)remains a significant challenge.Herein,we constructed S-doped ultra-fine RuO_(2) nanodots that were uniformly dispersed on carbon nanotubes.The incorporation of S effectively induces local rearrangement of the electronic structure of RuO_(2),thereby enhancing the dispersion of RuO_(2) as active sites and optimizing the adsorption free energy of H^(∗)intermediate.As ex-pected,the as-synthesized S-RuO_(2)/CNT delivers remarkable HER activity in all pH electrolytes,achieving lower overpotentials of 136,159,and 396 mV at 100 mA cm^(-2) in acidic,neutral,and basic solutions,respectively.Moreover,a unitary S-RuO_(2)/CNT electrolytic cell requires only a lower voltage(1.476 V)to achieve a current density of 10 mA cm^(-2) in 1.0 mol/L KOH.This ingenious work represents a significant breakthrough in the rational design of bifunctional electrocatalysts,enabling remarkable performance in electrochemical water electrolysis. 展开更多
关键词 RuO_(2)nanodots Electrocatalytic overall water splitting Sulphur anion doping Electronic structure regulation
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Recent development of LiNi_xCo_yMn_zO_2:Impact of micro/nano structures for imparting improvements in lithium batteries 被引量:8
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作者 潘成迟 Craig E.BANKS +3 位作者 宋维鑫 王驰伟 陈启元 纪效波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期108-119,共12页
The recent advancement in the design,synthesis,and fabrication of micro/nano structured LiNixCoyMnzO2 with one-,two-,and three-dimensional morphologies was reviewed.The major goal is to highlight LiNixCoyMnzO2 materia... The recent advancement in the design,synthesis,and fabrication of micro/nano structured LiNixCoyMnzO2 with one-,two-,and three-dimensional morphologies was reviewed.The major goal is to highlight LiNixCoyMnzO2 materials,which have been utilized in lithium ion batteries with enhanced energy and power density,high energy efficiency,superior rate capability and excellent cycling stability resulting from the doping,surface coating,nanocomposites and nano-architecturing. 展开更多
关键词 lithium-ion battery micro/nano structures LiNixCoyMnzO2 DOPING surface coating composite materials
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掺杂和点缺陷调控MoS_(2)/ZnO异质结光解水性能的第一性原理研究 被引量:1
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作者 温俊青 王嘉辉 张建民 《高等学校化学学报》 北大核心 2025年第2期143-154,共12页
采用第一性原理计算方法研究了C,Pd元素掺杂及点缺陷MoS_(2)/ZnO异质结的电子结构、光学性质及光催化性能.计算结果表明,本征MoS_(2)/ZnO异质结具有0.66 eV的直接带隙,带边位置呈现Ⅱ型能带排列.掺杂和缺陷可以有效减小MoS_(2)/ZnO异质... 采用第一性原理计算方法研究了C,Pd元素掺杂及点缺陷MoS_(2)/ZnO异质结的电子结构、光学性质及光催化性能.计算结果表明,本征MoS_(2)/ZnO异质结具有0.66 eV的直接带隙,带边位置呈现Ⅱ型能带排列.掺杂和缺陷可以有效减小MoS_(2)/ZnO异质结的带隙,Pd@Zn为磁性半导体,V_(Mo)和V_(Zn)体系具有磁性半金属特性.掺杂和缺陷使MoS_(2)/ZnO异质结禁带之中出现杂质能级,有利于电子跃迁,吸收范围扩展至红外波段,在可见光范围(500~760 nm)内的光吸收系数提高.本征、掺杂与缺陷MoS_(2)/ZnO异质结体系界面处均存在由ZnO层指向MoS_(2)层的内建电场,促使本征MoS_(2)/ZnO异质结,C@S_(2),Pd@Zn,V_(S1),V_(S2)和V_(O)体系形成直接Z型异质结,促进了光生电子-空穴对的有效分离.异质结的带边电位跨过pH=0和7时的氧化还原电位,表明这些异质结可以在强酸溶液与中性溶液条件下进行氧化还原反应,且载流子具有较强的氧化还原能力.研究结果为基于MoS_(2)/ZnO异质结的设计提供了理论参考. 展开更多
关键词 MoS_(2)/Zno异质结 掺杂缺陷 电子结构 光催化性能
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SnO_(2)的异质结构构建及光催化性能研究
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作者 赵丽 董婷 +1 位作者 杨文龙 陈其虎 《辽宁化工》 2025年第1期6-9,共4页
随着工业不断发展,各类污染物急剧增加,低成本、高效降解污染物成了研究人员的研究重点。光催化技术是处理水污染的最佳手段之一,SnO_(2)因廉价、无毒、稳定、耐酸碱等特点备受瞩目,但由于其带隙较宽应用受限。相关研究表明SnO_(2)的异... 随着工业不断发展,各类污染物急剧增加,低成本、高效降解污染物成了研究人员的研究重点。光催化技术是处理水污染的最佳手段之一,SnO_(2)因廉价、无毒、稳定、耐酸碱等特点备受瞩目,但由于其带隙较宽应用受限。相关研究表明SnO_(2)的异质结构复合材料表现出很好的协同效应。本论文对SnO_(2)的异质结构的构建、使用现状、应用进展进行了论述,并对其发展前景进行了展望。 展开更多
关键词 Sno_(2) 异质结构 光催化
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ScCO_(2)作用下含水性对煤化学组成和结构的影响
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作者 张小东 孙泽源 +3 位作者 张瑜 张硕 李勇 杜志刚 《煤炭学报》 北大核心 2026年第1期678-688,共11页
深部煤层封存CO_(2)过程中,CO_(2)常处于超临界状态(ScCO_(2)),与水、煤存在复杂的物理化学反应,促使煤的化学组成和结构发生变化,进而影响CO_(2)地质封存的效果。为研究不同含水条件下ScCO_(2)对煤化学组成和结构的影响,以焦煤为研究对... 深部煤层封存CO_(2)过程中,CO_(2)常处于超临界状态(ScCO_(2)),与水、煤存在复杂的物理化学反应,促使煤的化学组成和结构发生变化,进而影响CO_(2)地质封存的效果。为研究不同含水条件下ScCO_(2)对煤化学组成和结构的影响,以焦煤为研究对象,开展了不同含水率下ScCO_(2)-煤反应试验,对比反应前后煤的化学组成和结构的差异,探讨含水性对ScCO_(2)-煤反应的影响机制。结果表明:ScCO_(2)对煤中碳酸盐矿物溶解性较强,其次是黏土矿物,随含水率增大,反应残余煤中碳酸盐矿物的质量分数先增后减;较大含水率时,ScCO_(2)与煤中碳酸盐矿物的反应强于黏土矿物,故碳酸盐矿物减少更为显著。ScCO_(2)与H_(2)O对煤化学结构中含氧官能团的影响较大,而对芳香烃、脂肪烃的影响较小;ScCO_(2)导致煤中含氧官能团含量降低,随水分增加,富氧指数(I_(2))显著增大,而富氢指数(I_(1))、芳香度(I_(3))和缩聚度(I_(4))变化较小。ScCO_(2)的溶胀作用,使芳香层间距(d_(002))增大,同时延展度(L_(a))、芳香层数(N_(c))、芳碳率(f_(a)')和脂碳率(f_(al))均减小;随水分增加,d_(002)、L_(a)和f_(a)'先增后减,L_(c)、N_(c)和f_(al)的变化趋势则相反。水分在一定程度上可提升ScCO_(2)对煤低分子化合物的萃取效果,促进煤芳香结构无序化,但随水分含量进一步增大,水分将会阻止CO_(2)进入煤体,煤中碳酸盐矿物先一步与ScCO_(2)反应,进而弱化ScCO_(2)对煤有机质的萃取效应,表现为空气干燥基态时ScCO_(2)对煤有机质的溶出量和化学结构破坏的影响更明显,饱水态时矿物质的溶蚀更显著。 展开更多
关键词 ScCO_(2) 含水率 矿物组成 官能团 化学结构
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Na_(2)SO_(4)溶液对滨海软土压缩及微观特性的影响
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作者 雷华阳 战持润 章纬地 《地下空间与工程学报》 北大核心 2026年第1期150-158,170,共10页
为了研究水化学环境对滨海软土力学性质的影响,对孔隙水环境为Na_(2)SO_(4)、不同含盐量的饱和土体开展了一维固结试验和微观扫描电镜试验。结果表明:随着含盐量的增加,滨海软土结构屈服应力减小,最大减小幅度为9.5%,压缩指数呈线性增大... 为了研究水化学环境对滨海软土力学性质的影响,对孔隙水环境为Na_(2)SO_(4)、不同含盐量的饱和土体开展了一维固结试验和微观扫描电镜试验。结果表明:随着含盐量的增加,滨海软土结构屈服应力减小,最大减小幅度为9.5%,压缩指数呈线性增大,渗透系数增大;当含盐量大于4%时,析出的芒硝晶体赋存于颗粒孔隙之间,土体骨架效应明显,导致土体结构屈服应力增大,压缩指数与渗透系数减小;扫描电镜图像显示含盐量的增加使滨海软土平均粒径增大,絮凝结构土颗粒增多。此外,建立了考虑含盐量和固结压力的滨海软土结构性参数,结果表明:随着固结压力的增加结构性参数减小;当固结压力小于结构屈服应力时,随着含盐量的增大,结构性参数先减小后增大,当固结压力大于结构屈服应力时,结构性参数随含盐量的增加变化不显著。 展开更多
关键词 Na_(2)SO_(4) 含盐量 压缩特性 结构性参数 微观孔隙结构
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MOF基材料光催化CO_(2)还原为C1产物的研究进展
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作者 马晓宇 张更新 +3 位作者 贾宇桐 支凯旋 周阿武 李建荣 《北京工业大学学报》 北大核心 2026年第1期107-116,共10页
光催化CO_(2)还原技术清洁环保,被认为是最有希望的解决方案之一。近年来,金属-有机框架(metalorganic frameworks,MOF)在光催化CO_(2)还原应用中取得了一些研究成果,同时,其明确结构也有利于研究光催化过程中的构效关系。系统总结了MO... 光催化CO_(2)还原技术清洁环保,被认为是最有希望的解决方案之一。近年来,金属-有机框架(metalorganic frameworks,MOF)在光催化CO_(2)还原应用中取得了一些研究成果,同时,其明确结构也有利于研究光催化过程中的构效关系。系统总结了MOF基催化剂在光催化CO_(2)还原为C1产物方面的最新研究进展,重点阐述了MOF基光催化剂制备策略,其中包括缺陷工程、形态学控制、配体和取代基功能化、掺杂和引入助催化剂、金属簇/纳米粒子修饰、异质结设计与带隙工程和封装量子点等,以及探讨了MOF基光催化剂在光催化CO_(2)还原反应中的构效关系。最后,对MOF基光催化CO_(2)还原研究方向进行了展望。 展开更多
关键词 光催化 金属-有机框架(MOF) CO_(2)还原 碳中和 制备方法 构效关系
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NaOH-Na_(2)SO_(3)协同预处理调控桉木孔隙结构及树脂改性性能研究
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作者 覃引鸾 庞小莉 +2 位作者 陈龙海 郑小蓉 龙大军 《森林防火》 2026年第1期137-144,共8页
针对人工林桉树(Eucalyptus spp.)木材密度高、微纤丝角大导致的干燥开裂率高及吸湿膨胀率大等问题,提出分步改性策略:1)采用NaOH—Na_(2)SO_(3)混合溶液预处理优化孔隙结构;2)通过三聚氰胺改性脲醛树脂(MUF)浸渍增强疏水性。以大花序桉... 针对人工林桉树(Eucalyptus spp.)木材密度高、微纤丝角大导致的干燥开裂率高及吸湿膨胀率大等问题,提出分步改性策略:1)采用NaOH—Na_(2)SO_(3)混合溶液预处理优化孔隙结构;2)通过三聚氰胺改性脲醛树脂(MUF)浸渍增强疏水性。以大花序桉(Eucalyptus cloeziana)和尾叶桉(Eucalyptus urophylla)为对象,以及压汞法等方法分析预处理对木材细胞壁孔隙结构、化学成分及树脂浸渍性能的影响。结果表明:3%~5%NaOH与Na_(2)SO_(3)(比例0.83)混合溶液预处理可脱除55%以上木质素,同时抑制纤维素氧化降解,孔隙率提升至50.60%(大花序桉)和42.83%(尾叶桉);树脂改性后木材抗吸水率(WRE)达63.71%,抗膨胀率(ASE)提高至67.42%,尺寸稳定性显著改善。研究揭示了预处理-树脂改性协同作用机制,为速生桉木高值化利用提供了理论支持与技术路径。 展开更多
关键词 桉木 NaOH—Na_(2)SO_(3)预处理 孔隙结构 树脂改性 尺寸稳定性
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Synthesis,Crystal Structure and Antimicrobial Study of a New Schiff Base 2-{(2'-Benzyl)iminoethyl}-5-methoxyphenol 被引量:10
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作者 XU Tong-Tao GAO Jian +4 位作者 XU Xing-You NIU Shao-Rui YANG Xu-Jie LU Lu-De WANG Xin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期801-804,共4页
The Schiff base, 2-{(2′-benzyl)iminoethyl}-5-methoxyphenol (C6H4CH2N=C(CH3)C6H3- (OMe-5)OH) 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound cr... The Schiff base, 2-{(2′-benzyl)iminoethyl}-5-methoxyphenol (C6H4CH2N=C(CH3)C6H3- (OMe-5)OH) 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the orthorhombic system, space group Pbca with a = 8.9849(10), b = 13.2699(15), c = 22.975(2) A ,V= 2739.3(5) A^3, Mr= 255.31, Z= 8, F(000) = 1088, Dc = 1.238 g/cm^3, T= 293 K, μ = 0.082 mm^-1, λ = 0.71073 .A, the final R = 0.0596 and wR = 0.1575 for 1934 observed reflections with I 〉 2σ(I). The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms. 展开更多
关键词 2-hydroxyi-4-methoxyacetophenone benzyi amine crystal structure antimicrobiai activity
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