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A review on electrocatalytic CO_(2) conversion via C-C and C-N coupling
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作者 Zhuangzhi Zhang Sijun Li +6 位作者 Zheng Zhang Zhou Chen Hua Wang Xianguang Meng Wenquan Cui Xiwei Qi Jiacheng Wang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期167-194,共28页
Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of... Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of CO_(2) reduction products.The development of high-performance catalysts is the key to the both electrocatalytic reactions.In this review,we present a systematic summary of the reaction systems for electrocatalytic CO_(2) reduction,along with the coupling mechanisms of C-C and C-N bonds over outstanding electrocatalytic materials recently developed.The key intermediate species and reaction pathways related to the coupling as well as the catalyst-structure relationship will be also discussed,aiming to provide insights and guidance for designing efficient CO_(2) reduction systems. 展开更多
关键词 C-C coupling C-N coupling CO_(2) conversion ELECTROCATALYSIS urea synthesis
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Photothermal catalytic C-C coupling to ethylene from CO_(2) with high efficiency by synergistic cooperation of oxygen vacancy and half-metallic WTe_(2)
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作者 Xiaoyue Zhang Yong Yang +4 位作者 Yingjie Hu Lijun Xiong Tianyu Wang Panjie Li Jinyou Shen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期547-556,I0014,共11页
Photothermal catalytic CO_(2) conversion provides an effective solution targeting carbon neutrality by synergistic utilization of photon and heat.However,the C-C coupling initiated by photothermal catalysis is still a... Photothermal catalytic CO_(2) conversion provides an effective solution targeting carbon neutrality by synergistic utilization of photon and heat.However,the C-C coupling initiated by photothermal catalysis is still a big challenge.Herein,a three-dimensional(3D)hierarchical W_(18)O_(49)/WTe_(2) hollow nanosphere is constructed through in-situ embodying of oxygen vacancy and tellurium on the scaffold of WO_(3).The light absorption towards near-infrared spectral region and CO_(2) adsorption are enhanced by the formation of half-metal WTe_(2) and the unique hierarchical hollow architecture.Combining with the generation of oxygen vacancy with strengthened CO_(2) capture,the photothermal effect on the samples can be sufficiently exploited for activating the CO_(2) molecules.In particular,the close contact between W_(18)O_(49)and WTe_(2) largely promotes the photoinduced charge separation and mass transfer,and thus the~*CHO intermediate formation and fixedness are facilitated.As a result,the C-C coupling can be evoked between tungsten and tellurium atoms on WTe_(2).The ethylene production by optimized W_(18)O_(49)/WTe_(2) reaches 147.6μmol g^(-1)with the selectivity of 80%.The in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and density functional theory(DFT)calculations are performed to unveil the presence and significance of aldehyde intermediate groups in C-C coupling.The half-metallic WTe_(2) cocatalyst proposes a new approach for efficient CO_(2) conversion with solar energy,and may especially create a new platform for the generation of multi-carbon products. 展开更多
关键词 Photothermal catalysis HALF-METAL WTe_(2) C–C coupling Carbon neutrality
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Insight into the synergistic effect of defect and strong interface coupling on ZnIn_(2)S_(4)/CoIn_(2)S_(4)heterostructure for boosting photocatalytic H_(2) evolution
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作者 Xuehua Wang Tianyu Shi +6 位作者 Xianghu Wang Aili Song Guicun Li Lei Wang Jianfeng Huang Alan Meng Zhenjiang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期151-161,共11页
Steering the directional carrier migration across the interface is a central mission for efficient photocatalytic reactions.In this work,an atomic-shared heterointerface is constructed between the defect-rich ZnIn_(2)... Steering the directional carrier migration across the interface is a central mission for efficient photocatalytic reactions.In this work,an atomic-shared heterointerface is constructed between the defect-rich ZnIn_(2)S_(4)(HVs-ZIS)and CoIn_(2)S_(4)(CIS)via a defect-guided heteroepitaxial growth strategy.The strong interface coupling induces adequate carriers exchanging passageway between HVs-ZIS and CIS,enhancing the internal electric field(IEF)in the ZnIn_(2)S_(4)/CoIn_(2)S_(4)(HVs-ZIS/CIS)heterostructure.The defect structure in HVs-ZIS induces an additional defect level,improving the separation efficiency of photocarriers.Moreover,promoted by the IEF and intimate heterointerface,photogenerated electrons trapped by the defect level can migrate to the valence band of CIS,contributing to massive photogenerated electrons with intense reducibility in HVs-ZIS/CIS.Consequently,the HVs-ZIS/CIS heterostructure performs a boosted H_(2)evolution activity of 33.65 mmol g^(-1)h^(-1).This work highlights the synergistic effects of defect and strong interface coupling in regulating carrier transfer and paves a brave avenue for constructing efficient heterostructure photocatalysts. 展开更多
关键词 Defect-guided heteroepitaxial growth Heterointerface coupling Photocatalytic H_(2)evolution Mechanism HVs-ZIS/CIS
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Dual-Schottky-junctions coupling device based on ultra-longβ-Ga_(2)O_(3)single-crystal nanobelt and its photoelectric properties
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作者 Haifeng Chen Xiaocong Han +9 位作者 Chenlu Wu Zhanhang Liu Shaoqing Wang Xiangtai Liu Qin Lu Yifan Jia Zhan Wang Yunhe Guan Lijun Li Yue Hao 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期90-98,共9页
High qualityβ-Ga_(2)O_(3)single crystal nanobelts with length of 2−3 mm and width from tens of microns to 132μm were synthesized by carbothermal reduction method.Based on the grown nanobelt with the length of 600μm... High qualityβ-Ga_(2)O_(3)single crystal nanobelts with length of 2−3 mm and width from tens of microns to 132μm were synthesized by carbothermal reduction method.Based on the grown nanobelt with the length of 600μm,the dual-Schottky-junctions coupling device(DSCD)was fabricated.Due to the electrically floating Ga_(2)O_(3)nanobelt region coupling with the double Schottky-junctions,the current I_(S2)increases firstly and rapidly reaches into saturation as increase the voltage V_(S2).The saturation current is about 10 pA,which is two orders of magnitude lower than that of a single Schottky-junction.In the case of solar-blind ultraviolet(UV)light irradiation,the photogenerated electrons further aggravate the coupling physical mechanism in device.I_(S2)increases as the intensity of UV light increases.Under the UV light of 1820μW/cm^(2),I_(S2)quickly enters the saturation state.At V_(S2)=10 V,photo-to-dark current ratio(PDCR)of the device reaches more than 104,the external quantum efficiency(EQE)is 1.6×10^(3)%,and the detectivity(D*)is 7.5×10^(12)Jones.In addition,the device has a very short rise and decay times of 25−54 ms under different positive and negative bias.DSCD shows unique electrical and optical control characteristics,which will open a new way for the application of nanobelt-based devices. 展开更多
关键词 β-Ga_(2)O_(3)nanobelt carbothermal reduction UV light dual-Schottky coupling device
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CAS-ESM2.0 Successfully Reproduces Historical Atmospheric CO_(2) in a Coupled Carbon−Climate Simulation
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作者 Jiawen ZHU Juanxiong HE +6 位作者 Duoying JI Yangchun LI He ZHANG Minghua ZHANG Xiaodong ZENG Kece FEI Jiangbo JIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期572-580,共9页
The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to... The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth system.Earth system models are widely used to investigate these interactions via coupled carbon-climate simulations.The Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the ocean.Using CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven experiment.This paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)product.The results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high latitudes.These agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes involved.This paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality. 展开更多
关键词 CAS-ESM atmospheric CO_(2) coupled carbon-climate simulation emissions-driven CMIP6 experiment
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Strongly Coupled Ag/Sn-SnO_(2)Nanosheets Toward CO_(2)Electroreduction to Pure HCOOH Solutions at Ampere‑Level Current
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作者 Min Zhang Aihui Cao +5 位作者 Yucui Xiang Chaogang Ban Guang Han Junjie Ding Li‑Yong Gan Xiaoyuan Zhou 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期212-226,共15页
Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance... Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance electrocatalysts.Herein,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible sites.As a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to formate.Additionally,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 h.This work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2). 展开更多
关键词 Electrochemical CO_(2)reduction coupled Ag/Sn-SnO_(2)nanosheets Electronic structure Porous solid electrolyte PURE
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A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm
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作者 苏静明 方士辉 +1 位作者 洪炎 温言 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期233-243,共11页
A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are con... A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc. 展开更多
关键词 color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling
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Recent advances in paired electrolysis coupling CO_(2) reduction with alternative oxidation reactions 被引量:1
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作者 Deng Li Jiangfan Yang +2 位作者 Juhong Lian Junqing Yan Shengzhong(Frank) Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期406-419,I0011,共15页
Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)holds great promise in green energy conversion and storage.However,for current CO_(2) electrolyzers that rely on the oxygen evolution reaction,a large portion of the... Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)holds great promise in green energy conversion and storage.However,for current CO_(2) electrolyzers that rely on the oxygen evolution reaction,a large portion of the input energy is"wasted"at the anode due to the high overpotential requirement and the recovery of low-value oxygen.To make efficient use of the electricity during electrolysis,coupling CO_(2)RR with anodic alternatives that have low energy demands and/or profitable returns with high-value products is then promising.Herein,we review the latest advances in paired systems for simultaneous CO_(2) reduction and anode valorization.We start with the cases integrating CO_(2)RR with concurrent alternative oxidation,such as inorganic oxidation using chloride,sulfide,ammonia and urea,and organic oxidation using alcohols,aldehydes and primary amines.The paired systems that couple CO_(2)RR with on-site oxidative upgrading of CO_(2)-reduced chemicals are also introduced.The coupling mechanism,electrochemical performance and economic viability of these co-electrolysis systems are discussed.Thereby,we then point out the mismatch issues between the cathodic and anodic reactions regrading catalyst ability,electrolyte solution and reactant supply that will challenge the applications of these paired electrolysis systems.Opportunities to address these issues are further proposed,providing some guidance for future research. 展开更多
关键词 ELECTROLYSIS coupling Reaction CO_(2)Utilization Co-Valorization
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Electro-enzyme coupling systems for selective reduction of CO_(2) 被引量:1
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作者 Yuman Guo Xueming Hong +1 位作者 Ziman Chen Yongqin Lv 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期140-162,I0005,共24页
To address the energy crisis and alleviate the rising level of CO_(2)in the atmosphere,various CO_(2)capture and utilization(CCU)technologies have been developed.The use of electro-enzyme coupling systems is a promisi... To address the energy crisis and alleviate the rising level of CO_(2)in the atmosphere,various CO_(2)capture and utilization(CCU)technologies have been developed.The use of electro-enzyme coupling systems is a promising strategy for the sustainable production of fuels,chemicals and materials using CO_(2)as the feedstock.In this review,the recent progresses in the development of electro-enzyme coupling systems for the selective reduction of CO_(2)are systematically summarized.We first provide a brief background about the significance and challenges in the direct conversion of CO_(2)into value-added chemicals.Next,we describe the materials and strategies in the design of electrodes,as well as the common enzymes used in the electro-enzyme coupling systems.Then,we focus on the state-of-the-art routes for the electro-enzyme coupling conversion of CO_(2)into a variety of compounds(formate,CO,methanol,C≥2chemicals)by a single enzyme or multienzyme systems.The emerging approaches and materials used for the construction of electro-enzyme coupling systems to enhance the electron transfer efficiency and the catalytic activity/stability are highlighted.The main challenges and perspectives in the integration of enzymatic and electrochemical strategies are also discussed. 展开更多
关键词 Electro-enzyme coupling CO_(2)reduction ELECTROCHEMISTRY ENZYME Electron transfer
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Charge-Transfer and SERS Coupling on TiO2
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作者 Syed K. Islam Antonio Ponte 《American Journal of Analytical Chemistry》 CAS 2023年第11期519-530,共12页
We report the SERS enhancements of Raman forbidden surface modes of TiO<sub>2</sub> in different sized TiO<sub>2</sub> crystals. This current study utilizes the relationship between the vibroni... We report the SERS enhancements of Raman forbidden surface modes of TiO<sub>2</sub> in different sized TiO<sub>2</sub> crystals. This current study utilizes the relationship between the vibronic coupling and the degree of charge-transfer to explain the differences of Surface Enhanced Raman Scattering (SERS) enhancements. Our study shows a direct correlation between the degree of charge-transfer and vibronic coupling. This relationship suggests that charge-transfer between the N-719 dye and TiO<sub>2</sub> due to vibronic coupling plays a fundamental role in SERS enhancements. Furthermore, this study shows a strong dependence of the enhancements of the N-719 dye molecular modes to that of the surface modes. This indicates that the mechanism that governs the enhancements of the surface modes in TiO<sub>2</sub> crystals most likely also dictates the enhancements of the N-719 dyes. 展开更多
关键词 CHARGE-TRANSFER Vibronic coupling Fano Profile TiO2 Sur-face Modes
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Multi-dimensional Simulation of Phase Change by a 0D-2D Model Coupling via Stefan Condition
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作者 Adrien Drouillet Romain Le Tellier +2 位作者 Raphaël Loubère Mathieu Peybernes Louis Viot 《Communications on Applied Mathematics and Computation》 2023年第2期853-884,共32页
Considering phase changes associated with a high-temperature molten material cooled down from the outside,this work presents an improvement of the modelling and the numerical simulation of such processes for an applic... Considering phase changes associated with a high-temperature molten material cooled down from the outside,this work presents an improvement of the modelling and the numerical simulation of such processes for an application pertaining to the safety of light water nuclear reactors.Postulating a core meltdown accident,the behaviour of the core melt(aka corium)into a steel vessel is of tremendous importance when evaluating the vessel integrity.Evaluating correctly the heat fluxes requires the numerical simulation of the interaction between the liquid material and its solid counterpart which forms during the solidification process,but also may melt back.To simulate this configuration,encoun-tered in various industrial applications,one considers a bi-phase model constituted by a liquid phase in contact and interaction with its solid phase.The liquid phase may solidify in presence of low energetic source,while the solid phase may melt due to an intense heat flux from the high-temperature liquid.In the frame of the in-house legacy code,several simplifying assumptions(0D multi-layer discretization,instantaneous heat transfer via a quadratic temperature profile in solids)are made for the modelling of such phase changes.In the present work,these shortcomings are illustrated and further overcome by solving a 2D heat conduction model in the solid by a mixed Raviart-Thomas finite element method coupled to the liquid phase due to heat and mass exchanges through Stefan condition.The liquid phase is modeled with a 0D multi-layer approach.The 0D-liquid and 2D-solid mod-els are coupled by a Stefan like phase change interface model.Several sanity checks are performed to assess the validity of the approach on 1D and 2D academical configurations for which exact or reference solutions are available.Then more advanced situations(genu-ine multi-dimensional phase changes and an"industrial-like scenario")are simulated to verify the appropriate behavior of the obtained coupled simulation scheme. 展开更多
关键词 Simulation of phase change FUSION SOLIDIFICATION 0D multi-layer model 2D heat conduction model Model coupling
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Recent progress in C-N coupling for electrochemical CO_(2) reduction with inorganic nitrogenous species in aqueous solution
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作者 Shuxia Liu Tanyuan Wang +1 位作者 Lior Elbaz Qing Li 《Materials Reports(Energy)》 2023年第1期65-77,I0003,共14页
The electrocatalytic CO_(2) reduction in aqueous solution mainly involves bond cleavage and formation between C,H and O,and it is highly desirable to expand the bond formation reaction of C with other atoms to obtain ... The electrocatalytic CO_(2) reduction in aqueous solution mainly involves bond cleavage and formation between C,H and O,and it is highly desirable to expand the bond formation reaction of C with other atoms to obtain novel and valuable chemicals.The electrochemical synthesis of N-containing organic chemicals in electrocatalytic CO_(2) reduction via introducing N sources is an effective strategy to expand the product scope,since chemicals con-taining C–N bonds(e.g.amides and amines)are important reactants/products for medicine,agriculture and in-dustry.This article focuses on the research progress of C–N coupling from CO_(2) and inorganic nitrogenous species in aqueous solution.Firstly,the reaction pathways related to the reaction intermediates for urea,formamide,acetamide,methylamine and ethylamine are highlighted.Then,the electrocatalytic performance of different catalysts for these several N-containing products are summarized and classified.Finally,the challenges and op-portunities are analyzed,aiming to provide general insights into future research directions for electrocatalytic C–N coupling. 展开更多
关键词 CO_(2) reduction C-N coupling Heterogeneous electrocatalysis AMIDE AMINE
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超声耦合TiO_(2)/UV光催化处理对玉米秸秆组分影响研究
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作者 陆佳 苏小红 +1 位作者 尤宏梅 刘泽 《化学工程师》 CAS 2024年第2期9-12,37,共5页
本文采用超声耦合Ti O_(2)/UV光催化处理玉米秸秆,探究处理条件对玉米秸秆组分及结构的影响。研究结果表明,在Ti O_(2)投加量为0.25g·L^(-1)、pH值为8.25、超声强度为0.625W·m L^(-1)、处理1h的条件下,玉米秸秆中木质素和半... 本文采用超声耦合Ti O_(2)/UV光催化处理玉米秸秆,探究处理条件对玉米秸秆组分及结构的影响。研究结果表明,在Ti O_(2)投加量为0.25g·L^(-1)、pH值为8.25、超声强度为0.625W·m L^(-1)、处理1h的条件下,玉米秸秆中木质素和半纤维素含量分别由未处理前的26.06%、20.58%降低到22.85%、18.39%,纤维素含量由37.67%增加到40.39%。超声耦合Ti O_(2)/UV光催化处理可以破坏玉米秸秆的结构,玉米秸秆断裂破碎成细小碎片,表面粗糙有褶皱。本研究可为超声耦合Ti O_(2)/UV光催化技术在玉米秸秆预处理中的应用提供技术参考。 展开更多
关键词 超声 耦合 TiO_(2)/UV光催化 玉米秸秆 组分变化
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Ga_(2-x)Fe_(x)O_(3) 单相多铁性及室温磁电耦合效应的研究进展
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作者 张军 马建春 薛武红 《中国陶瓷》 CAS CSCD 北大核心 2024年第3期1-11,共11页
在单相多铁材料中,利用电场代替磁场来可逆控制磁性这一手段是实现下一代高密度、低功耗磁电多功能器件的理想方法。然而,目前所发现的单相多铁材料大多数都表现出了弱的室温铁电性、铁磁性或者低于室温的磁电工作温度,这严重限制了其... 在单相多铁材料中,利用电场代替磁场来可逆控制磁性这一手段是实现下一代高密度、低功耗磁电多功能器件的理想方法。然而,目前所发现的单相多铁材料大多数都表现出了弱的室温铁电性、铁磁性或者低于室温的磁电工作温度,这严重限制了其在实际生产中的应用。近年来的研究发现,具有强磁电(ME)耦合的第Ⅱ类室温单相多铁Ga_(2-x)Fe_(x)O_(3),其剩余铁电极化强度(Pr)和饱和磁化强度(Ms)在最优的条件下分别可以达到25μC/cm^(2)和1.2μB/f.u.,因而是一种极有可能同时解决上述问题的新型替代材料。首先介绍了单相多铁材料的研究现状以及潜在的应用;然后总结了Ga_(2-x)Fe_(x)O_(3)材料单相多铁性和ME耦合效应的研究历程;最后,围绕Ga_(2-x)Fe_(x)O_(3)未来面临的关键科学问题和挑战进行了详细讨论。 展开更多
关键词 单相多铁性 Ga_(2-x)Fe_(x)O_(3) 铁电性 铁磁性 磁电耦合
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自旋-轨道耦合对双层钙钛矿Ba_(2)CoOsO_(6)电磁性质的影响
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作者 李洪苹 孙安 +1 位作者 张瑶明 郭宝昌 《江苏大学学报(自然科学版)》 CAS 北大核心 2024年第6期739-744,共6页
采用第一性原理计算方法,研究了双层钙钛矿氧化物Ba_(2)CoOsO_(6)的晶体结构、电子结构及自旋-轨道耦合作用(SOC)对其电磁性质的影响,并分析电子结构和自旋-轨道耦合作用对其宏观物理性质的影响.结果表明:Ba_(2)CoOsO_(6)为反铁磁窄带... 采用第一性原理计算方法,研究了双层钙钛矿氧化物Ba_(2)CoOsO_(6)的晶体结构、电子结构及自旋-轨道耦合作用(SOC)对其电磁性质的影响,并分析电子结构和自旋-轨道耦合作用对其宏观物理性质的影响.结果表明:Ba_(2)CoOsO_(6)为反铁磁窄带隙半导体,存在Os1/Co1反位缺陷;电子结构的分析结果证实了Ba_(2)CoOsO_(6)的电荷分布为Ba_(2)^(2+)Co^(2+)Os^(6+)O_(6)^(2-),确定了2价Co离子和6价Os离子的存在;SOC的存在减小了Co离子和Os离子的自旋磁矩,同时减小了带隙;根据第一性原理计算结果可知,自旋-轨道耦合作用对电子结构和电磁性质的影响不可忽视,相较于其他方法,该方法计算值与试验分析结果更接近,也验证了理论计算的准确性. 展开更多
关键词 Ba_(2)CoOsO_(6) 双层钙钛矿 自旋-轨道耦合 第一性原理计算 反铁磁耦合 半导体
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咪唑杂环与2-氨基苯并噻唑化合物交叉偶联产物探索合成
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作者 李术艳 《广州化工》 CAS 2024年第9期51-53,共3页
研究了咪唑杂环化合物与2-氨基苯并噻唑化合物在亚硝酸叔丁酯和醋酸钾条件下的交叉偶联反应,制备了系列苯并噻唑类咪唑杂环化合物,产率中等至优异。研究表明,苯环上带有较强吸电子基团的2-氨基苯并噻唑类化合物参与反应产率较低,甚至不... 研究了咪唑杂环化合物与2-氨基苯并噻唑化合物在亚硝酸叔丁酯和醋酸钾条件下的交叉偶联反应,制备了系列苯并噻唑类咪唑杂环化合物,产率中等至优异。研究表明,苯环上带有较强吸电子基团的2-氨基苯并噻唑类化合物参与反应产率较低,甚至不发生反应。而在咪唑杂环并[2,1-b]噻唑杂环化合物底物中,噻唑环上具有取代芳基的底物表现较好,产率可达到90%以上。通过核磁共振氢谱、核磁共振碳谱、红外光谱、高效液质联用仪等分析方法对合成产物的结构进行了表征,证明了合成方法的可靠性。 展开更多
关键词 咪唑并[2 1-b]噻唑 2-氨基苯并噻唑 偶联
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Evaluation of Ventricular-vascular Coupling in Patients with Type 2 Diabetes Mellitus Using 2-Dimensional Speckle Tracking Imaging 被引量:20
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作者 李朝军 杜联芳 罗向红 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第6期929-934,共6页
The elastic and functional coupling of heart and vessels makes the stroke work (SW) of the heart optimal. Speckle tracking imaging (STI) can evaluate the myocardial strain and function. We studied ventricular-vasc... The elastic and functional coupling of heart and vessels makes the stroke work (SW) of the heart optimal. Speckle tracking imaging (STI) can evaluate the myocardial strain and function. We studied ventricular-vascular coupling in 80 diabetic patients with different systolic function using STI. The patients were divided into two groups according to ejection fraction (EF): the diabetes mel- litus with normal EF (DMN) group and the diabetes mellitus with abnormal EF (DMA) group. Forty-two volunteers served as control group. The relative wall thickness (RWT), left ventricular mass index (LVMI), stroke volume (SV), SW, rate-pressure product (RPP), systemic vascular resis- tance index (SVRI), left ventricular end-systolic elastance (Ees), effective arterial elasticity (Ea) and ventricular-vascular coupling index (VVI) were measured and calculated by conventional echocardi- ography. The longitudinal strain (LS) at basement (LSBA), papillary muscle (LSvM) and cardiac apex (LSAv) was assessed with STI. It was found: (A) compared with control group, in DMN and DMA groups, LSBA, LSvM and LSAp decreased, and they were lower in DMA group. (B) VVI, RPP and SVRI increased, and they were higher in DMN group; Ees decreased, and it was lower in DMA group. (C) LSBA, LSpM, and LSAv had negative correlation with VVI. LSAp, RWT, LVMI and SW were independent predictors for VVI. The area under the receiver operating characteristic (ROC) curves was used for identification of DMA and DMN with LSBA, LSpM, and LSAp, and the area under the ROC of LSAp was the largest. This study supports that myocardial LS could reflect the ventricu- lar-vascular coupling. Different segments had an order to “respond to” the state of the coupling, and the cardiac apex might be the earliest. 展开更多
关键词 ventricular-vascular coupling type 2 diabetes myocardial dysfunction ECHOCARDIOGRAPHY speckle tracking imaging
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基于CO_(2)水基压裂液的煤体软化及降尘技术应用 被引量:1
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作者 黄辉龙 冯俊文 +2 位作者 邓广哲 李红健 李龙龙 《煤炭技术》 CAS 2024年第1期129-132,共4页
为解决坚硬煤层条件下,常规煤体注水方式效果不好,回采过程中顶煤可放性差、工作面截煤和放煤过程中粉尘大的难题,根据金川煤矿煤层的具体情况,基于煤体压裂软化-润渗除尘理论,利用CO_(2)活性水耦合液、液相与气相耦合液,代替传统注水... 为解决坚硬煤层条件下,常规煤体注水方式效果不好,回采过程中顶煤可放性差、工作面截煤和放煤过程中粉尘大的难题,根据金川煤矿煤层的具体情况,基于煤体压裂软化-润渗除尘理论,利用CO_(2)活性水耦合液、液相与气相耦合液,代替传统注水和注气技术,在金川煤矿开展了煤体软化及降尘技术应用研究。CO_(2)活性水压裂软化润渗技术,能够使煤体中裂隙和孔隙的容积以及结构发生变化,造成煤体的破裂和松动,降低了煤炭强度,达到对硬煤最佳的软化效果。试验表明:煤层CO_(2)水基压裂后,放煤循环速度提高了5.6%,顶煤破碎块度均衡,顶煤平均采出率提高了3.2%;截割浮尘浓度降低45%,工作面能见度提高,工作面转载运输点煤尘降低23%,润渗作用有效降低了煤体产生浮尘的能力。 展开更多
关键词 厚硬煤层 压裂软化 CO_(2)耦合 软化性 润湿性
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CO_(2)与液态物质耦合对沉香形成及成分的影响
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作者 赵威威 周再知 +3 位作者 刘高峰 张青青 黄桂华 庞圣江 《华南农业大学学报》 CAS CSCD 北大核心 2024年第1期60-70,共11页
【目的】探明CO_(2)与液态物质(无机盐、激素和真菌)耦合对土沉香Aquilaria sinensis结香的诱导效果,寻求高效诱导土沉香结香的新方法,为人工诱导结香技术促进结香提供理论依据。【方法】以13年生土沉香为研究对象,采用CO_(2)与3种液态... 【目的】探明CO_(2)与液态物质(无机盐、激素和真菌)耦合对土沉香Aquilaria sinensis结香的诱导效果,寻求高效诱导土沉香结香的新方法,为人工诱导结香技术促进结香提供理论依据。【方法】以13年生土沉香为研究对象,采用CO_(2)与3种液态物质(无机盐、激素和真菌)耦合的方法诱导处理树体,1年后,取样观察沉香树体结香部位切片组织结构和内含物变化,并检测醇溶性挥发油含量及化学成分。【结果】1)不同诱导处理对土沉香木质部中的淀粉颗粒均有不同程度的消耗。木薄壁细胞内侵填物质通过导管–薄壁细胞间半具缘纹孔进入相邻导管内积累至完全堵塞。2)CO_(2)与3种液态物质(无机盐、激素和真菌)诱导处理中,射线薄壁细胞、轴向薄壁细胞和导管内油脂类物质积累存在差异,CK-1(只充CO_(2))仅存有少量油脂类物质,CK-2(只打孔不充CO_(2))未观察到油脂类物质。3)诱导变色范围受诱导方法影响较大,处理孔位置越远诱导变色距离越短,CO_(2)与无机盐联合诱导处理变色范围最大。4)不同诱导处理的醇溶性挥发油含量存在差异,黑褐色树脂越多含量越高。GCMS结果显示,5种诱导处理后共鉴定出74种化合物,其中共有的成分主要为11种,且部分醇溶性挥发油成分的相对含量在不同处理间差异较大。【结论】5种诱导方式所产沉香样品的醇溶性挥发油含量、沉香特征性成分及含量存在差异,CO_(2)与无机盐耦合诱导的土沉香特征性成分和含量均高于其他处理,诱导所产沉香品质最好,其次为CO_(2)与真菌联合诱导所产沉香,仅填充CO_(2)所产沉香品质较差。 展开更多
关键词 CO_(2) 耦合 树脂 化学成分 沉香 诱导方式
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基于产量和N_(2)O排放的温室番茄灌溉模式 被引量:1
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作者 段琳博 蔡焕杰 +2 位作者 孙亚楠 马静 杨楠 《农业环境科学学报》 CAS CSCD 北大核心 2024年第1期202-213,共12页
为了揭示设施菜地N_(2)O排放的变化规律,了解水肥气耦合对设施菜地土壤N_(2)O的影响,对不同水肥气处理进行综合评价,提出合理的减排措施。试验以番茄为供试作物,设置了灌水水平(I)、施肥水平(F)和加气水平(A)3个因素,以不加气(CK)充分... 为了揭示设施菜地N_(2)O排放的变化规律,了解水肥气耦合对设施菜地土壤N_(2)O的影响,对不同水肥气处理进行综合评价,提出合理的减排措施。试验以番茄为供试作物,设置了灌水水平(I)、施肥水平(F)和加气水平(A)3个因素,以不加气(CK)充分灌溉条件下2个施肥水平为对照,设置I1和I2(分别为亏缺灌溉和充分灌溉,对应作物-皿系数(K_(cp))分别为0.8和1.0)2个灌水水平,F1和F2(分别为低肥和高肥,对应施氮量为180 kg·hm^(-2)和240 kg·hm^(-2))2个施肥水平,A1和A2(分别为1倍气和2倍气)2个加气水平,共10个处理。采用静态暗箱-气相色谱法对番茄全生育期N_(2)O排放进行监测分析,系统研究水肥气耦合对温室番茄土壤N_(2)O排放的影响及其影响因素。结果表明:灌水量和施肥量的增加均会增加土壤N_(2)O排放通量,I2处理的N_(2)O排放通量比I1处理平均增加14.79%(P>0.05),F2处理比F1处理平均增加34.90%(P<0.05)。加气灌溉对土壤N_(2)O排放通量有显著影响,与CK处理相比,A1和A2处理分别增加10.02%(P>0.05)和62.92%(P<0.05)。土壤N_(2)O排放通量与土壤充水孔隙度呈指数正相关关系,与NO_(3)^(-)-N含量呈指数正相关关系,当土壤温度小于等于26℃时,N_(2)O排放通量与土壤湿度呈指数正相关关系,土壤温度大于26℃时,呈线性负相关关系。综合考虑番茄产量、N_(2)O累积排放量、灌溉水分利用效率、氮肥偏生产力和单产N_(2)O累积排放量,推荐施肥量为180 kg·hm^(-2)的1倍气充分灌溉(K_(cp)=1.0)为温室番茄增产、节水、减排的较佳灌溉模式。 展开更多
关键词 N_(2)O排放 水肥气耦合 温室番茄 土壤 灌水量 施肥量
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