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P-induced electron transfer interaction for enhanced selective hydrogenation rearrangement of furfural to cyclopentanone
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作者 Weichen Wang Hongke Zhang +4 位作者 Yidan Wang Fangyuan Zhou Zhiyu Xiang Wanbin Zhu Hongliang Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期43-51,共9页
Optimizing the intrinsic activity of non-noble metal by precisely tailoring electronic structure offers an appealing way to construct cost-effective catalysts for selective biomass valorization.Herein,we reported a P-... Optimizing the intrinsic activity of non-noble metal by precisely tailoring electronic structure offers an appealing way to construct cost-effective catalysts for selective biomass valorization.Herein,we reported a P-doping bifunctional catalyst(Ni-P/mSiO_(2))that achieved 96.6%yield for the hydrogenation rearrangement of furfural to cyclopentanone at mild conditions(1 MPaH_(2),150°C).The turnover frequency of Ni-P/mSiO_(2)was 411.9 h^(-1),which was 3.2-fold than that of Ni/mSiO_(2)(127.2 h^(-1)).Detailed characterizations and differential charge density calculations revealed that the electron-deficient Niδ+species were generated by the electron transfer from Ni to P,which promoted the ring rearrangement reaction.Density functional theory calculations illustrated that the presence of P atoms endowed furfural tilted adsorb on the Ni surface by the C=O group and facilitated the desorption of cyclopentanone.This work unraveled the connection between the localized electronic structures and the catalytic properties,so as to provide a promising reference for designing advanced catalysts for biomass valorization. 展开更多
关键词 FURFURAL Hydrogenation rearrangement P-DOPING electron transfer Biomass valorization
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Balancing electron transfer and intermediate adsorption ability of metallic Ni-Fe-RE-P bifunctional catalysts via 4f-2p-3d electron interaction for enhanced water splitting
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作者 Hong-Rui Zhao Cheng-Zong Yuan +8 位作者 Chenliang Zhou Wenkai Zhao Lunliang Zhang Cong-Hui Li Lei Xin Fuling Wu Shufeng Ye Xiaomeng Zhang Yunfa Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期458-465,共8页
Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking ... Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking efficient strategies.Herein,one efficient and universal strategy is developed to greatly regulate electronic structures of the metallic Ni-Fe-P catalysts via in-situ introducing the rare earth(RE)atoms(Ni-Fe-RE-P,RE=La,Ce,Pr,and Nd).Accordingly,the as-prepared optimal Ni-Fe-Ce-P/CC self-supported bifunctional electrodes exhibited superior electrocatalytic activity and excellent stability with the low overpotentials of 247 and 331 mV at 100 mA cm^(-2) for HER and OER,respectively.In the assembled electrolyzer,the Ni-Fe-Ce-P/CC as bifunctional electrodes displayed low operation potential of 1.49 V to achieve a current density of 10 mA cm^(-2),and the catalytic performance can be maintained for 100 h.Experimental results combined with density functional theory(DFT)calculation reveal that Ce doping leads to electron decentralization and crystal structure distortion,which can tailor the band structures and d-band center of Ni-Fe-P,further increasing conductivity and optimizing intermediate adsorption energy.Our work not only proposes a valuable strategy to regulate the electron transfer and intermediate adsorption of electrocatalysts via RE atoms doping,but also provides a deep under-standing of regulation mechanism of metallic electrocatalysts for enhanced water splitting. 展开更多
关键词 RE atoms electron transfer Adsorption energy Oxygen evolution Hydrogen evolution
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An active learning workflow for predicting hydrogen atom adsorption energies on binary oxides based on local electronic transfer features
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作者 Wenhao Jing Zihao Jiao +2 位作者 Mengmeng Song Ya Liu Liejin Guo 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1489-1496,共8页
Machine learning combined with density functional theory(DFT)enables rapid exploration of catalyst descriptors space such as adsorption energy,facilitating rapid and effective catalyst screening.However,there is still... Machine learning combined with density functional theory(DFT)enables rapid exploration of catalyst descriptors space such as adsorption energy,facilitating rapid and effective catalyst screening.However,there is still a lack of models for predicting adsorption energies on oxides,due to the complexity of elemental species and the ambiguous coordination environment.This work proposes an active learning workflow(LeNN)founded on local electronic transfer features(e)and the principle of coordinate rotation invariance.By accurately characterizing the electron transfer to adsorption site atoms and their surrounding geometric structures,LeNN mitigates abrupt feature changes due to different element types and clarifies coordination environments.As a result,it enables the prediction of^(*)H adsorption energy on binary oxide surfaces with a mean absolute error(MAE)below 0.18 eV.Moreover,we incorporate local coverage(θ_(l))and leverage neutral network ensemble to establish an active learning workflow,attaining a prediction MAE below 0.2 eV for 5419 multi-^(*)H adsorption structures.These findings validate the universality and capability of the proposed features in predicting^(*)H adsorption energy on binary oxide surfaces. 展开更多
关键词 Machine learning Adsorption energy Binary oxide electron transfer Active learning
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Fe-lnduced Electronic Transfer and Structural Evolution of Lotus Pod-Like CoNiFeP_(x)@P,N-C Heterostructure for Sustainable Oxygen Evolution
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作者 Xiaojun Zeng Qingqing Zhang +2 位作者 Chulong Jin Hui Huang Yanfeng Gao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期182-189,共8页
Transition metal phosphides with metallic properties are a promising candidate for electrocatalytic water oxidation,and developing highly active and stable metal phosphide-based oxygen evolution reaction catalysts is ... Transition metal phosphides with metallic properties are a promising candidate for electrocatalytic water oxidation,and developing highly active and stable metal phosphide-based oxygen evolution reaction catalysts is still challenging.Herein,we present a facile ion exchange and phosphating processes to transform intestine-like CoNiP_(x)@P,N-C into lotus pod-like CoNiFeP_(x)@P,N-C heterostructure in which numerous P,N-codoped carboncoated CoNiFeP_(x)nanoparticles tightly anchors on the 2D carbon matrix.Meanwhile,the as-prepared CoNiFeP_(x)@P,N-C enables a core-shell structure,high specific surface area,and hierarchical pore structure,which present abundant heterointerfaces and fully exposed active sites.Notably,the incorporation of Fe can also induce electron transfer in CoNiP_(x)@P,IM-C,thereby promoting the oxygen evolution reaction.Consequently,CoNiFeP_(x)@P,IM-C delivers a low overpotential of 278 mV(vs RHE)at a current density of10 mA cm^(-1)and inherits excellent long-term stability with no observable current density decay after 30 h of chronoamperometry test.This work not only highlights heteroatom induction to tune the electronic structure but also provides a facile approach for developing advanced and stable oxygen evolution reaction electrocatalysts with abundant heterointerfaces. 展开更多
关键词 electronic transfer Fe exchange multi-metal phosphides OER electrocatalysts structural evolution
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The surface electron transfer strategy promotes the hole of PDI release and enhances emerging organic pollutant degradation
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作者 Yunchuan Yang Dongyu Wang +2 位作者 Jisheng Geng Jun Liu Jun Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第10期84-91,共8页
In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair rec... In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair recombination in perylene diimide(PDI)organic semiconductors,we loaded ferric hydroxyl oxide(FeOOH)on PDI materials,successfully prepared novel FeOOH@PDI photocatalytic materials,and constructed a photo-Fenton system.The system was able to achieve highly efficient degradation of BPA under visible light,with a degradation rate of 0.112 min^(−1)that was 20 times higher than the PDI system,and it also showed universal degradation performances for a variety of emerging organic pollutants and anti-interference ability.The mechanism research revealed that the FeOOH has the electron trapping property,which can capture the photogenerated electrons on the surface of PDI,effectively reducing the compounding rate of photogenerated carriers of PDI and accelerating the iron cycling and H2O2 activation on the surface of FeOOH at the same time.This work provides new insights and methods for solving the problem of easy recombination of carriers in semiconductor photocatalysts and degrading emerging organic pollutants. 展开更多
关键词 perylene diimide organic semiconductors emerging pollutants surface electron transfer strategy PHOTO-FENTON
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Analysis of the electron transfer pathway in small laccase by EPR and UV-vis spectroscopy coupled with redox titration
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作者 Lu Yu Aokun Liu +3 位作者 Jian Kuang Ruotong Wei Zhiwen Wang Changlin Tian 《Magnetic Resonance Letters》 2024年第3期52-59,共8页
Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer betwe... Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer between substrate, copper centers, and O2is one of the key steps in the catalytic turnover of SLAC. However, limited research has been conducted on the electron transfer pathway of SLAC and SLAC-catalyzed reactions, hindering further engineering of SLAC to produce tunable biocatalysts for novel applications. Herein, the combinational use of electron paramagnetic resonance(EPR) and ultraviolet-visible(UV-vis) spectroscopic methods coupled with redox titration were employed to monitor the electron transfer processes and obtain further insights into the electron transfer pathway in SLAC. The reduction potentials for type 1 copper(T1Cu), type 2 copper(T2Cu) and type 3copper(T3Cu) were determined to be 367 ± 2 mV, 378 ± 5 m V and 403 ± 2 mV,respectively. Moreover, the reduction potential of a selected substrate of SLAC, hydroquinone(HQ), was determined to be 288 mV using cyclic voltammetry(CV). In this way, an electron transfer pathway was identified based on the reduction potentials. Specifically,electrons are transferred from HQ to T1Cu, then to T2Cu and T3Cu, and finally to O2.Furthermore, superhyperfine splitting observed via EPR during redox titration indicated a modification in the covalency of T2Cu upon electron uptake, suggesting a conformational alteration in the protein environment surrounding the copper sites, which could potentially influence the reduction potential of the copper sites during catalytic processes. The results presented here not only provide a comprehensive method for analyzing the electron transfer pathway in metalloenzymes through reduction potential measurements, but also offer valuable insights for further engineering and directed evolution studies of SLAC in the aim for biotechnological and industrial applications. 展开更多
关键词 electron paramagnetic resonance Redox titration electron transfer Reduction Potential Small laccase
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Coupling ferromagnetic ordering electron transfer channels and surface reconstructed active species for spintronic electrocatalysis of water oxidation 被引量:3
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作者 Zexing He Xiaokang Liu +7 位作者 Minghui Zhang Lei Guo Muhammad Ajmal Lun Pan Chengxiang Shi Xiangwen Zhang Zhen-Feng Huang Ji-Jun Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期570-580,I0014,共12页
Sluggish reaction kinetics of oxygen evolution reaction(OER), resulting from multistep proton-coupled electron transfer and spin constriction, limits overall efficiency for most reported catalysts. Herein, using model... Sluggish reaction kinetics of oxygen evolution reaction(OER), resulting from multistep proton-coupled electron transfer and spin constriction, limits overall efficiency for most reported catalysts. Herein, using modeled ZnFe_(2-x)Ni_xO_(4)(0 ≤ x ≤ 0.4) spinel oxides, we aim to develop better OER electrocatalyst through combining the construction of ferromagnetic(FM) ordering channels and generation of highly active reconstructed species. The number of symmetry-breaking Fe–O–Ni structure links to the formation of FM ordering electron transfer channels. Meanwhile, as the number of Ni^(3+)increases, more ligand holes are formed, beneficial for redirecting surface reconstruction. The electro-activated ZnFe_(1.6)Ni_(0.4)O_(4) shows the highest specific activity, which is 13 and 2.5 times higher than that of ZnFe_(2)O_(4) and unactivated ZnFe_(1.6)Ni_(0.4)O_(4), and even superior to the benchmark IrO_(2) under the overpotential of 350 mV. Applying external magnetic field can make electron spin more aligned, and the activity can be further improved to 39 times of ZnFe_(2)O_(4). We propose that intriguing FM exchange-field interaction at FM/paramagnetic interfaces can penetrate FM ordering channels into reconstructed oxyhydroxide layers, thereby activating oxyhydroxide layers as spin-filter to accelerate spin-selective electron transfer. This work provides a new guideline to develop highly efficient spintronic catalysts for water oxidation and other spin-forbidden reactions. 展开更多
关键词 Oxygen evolution reaction Reconstruction mechanism Metal oxyhydroxides electron transfer channels Ferromagnetic exchange-field penetration
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Promoting and controlling electron transfer of furfural oxidation efficiently harvest electricity,furoic acid,hydrogen gas and hydrogen peroxide
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作者 Denghao Ouyang Daihong Gao +2 位作者 Jinpeng Hong Zhao Jiang Xuebing Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期135-147,共13页
Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidatio... Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidation needs input of external electric energy.Herein,we developed a liquid flow fuel cell(LFFC)system to achieve oxidation of furfural in anode for furoic acid production with co-production of hydrogen gas.By controlling the electron transfer in cathode for reduction of oxygen,efficient generation of electricity or production of H_(2)O_(2)were achieved.Metal oxides especially Ag_(2)O have been screened as the efficient catalyst to promote the oxidation of aldehydes,while liquid redox couples were used for promoting the kinetics of oxygen reduction.A novel alkaline-acidic asymmetric design was also used for anolyte and catholyte,respectively,to promote the efficiency of electron transfer.Such an LFFC system achieves efficient conversion of chemical energy of aldehyde oxidation to electric energy and makes full use the transferred electrons for high-value added products without input of external energy.With(VO_(2))_(2)SO_(4)as the electron carrier in catholyte for four-electron reduction of oxygen,the peak output power density(Pmax)at room temperature reached 261 mW/cm^(2)with furoic acid and H_(2)yields of 90%and 0.10 mol/mol furfural,respectively.With anthraquinone-2-sulfonate(AQS)as the cathodic electron carrier,Pmaxof 60 mW/cm^(2)and furoic acid,H_(2)and H_(2)O_(2)yields of 0.88,0.15 and 0.41 mol/mol furfural were achieved,respectively.A new reaction mechanism on furfural oxidation on Ag_(2)O anode was proposed,referring to one-electron and two-electron reaction pathways depending on the fate of adsorbed hydrogen atom transferred from furfural aldehyde group. 展开更多
关键词 Oxidation of furfural Liquid flow fuel cell Electricity generation Hydrogen production electron transfer
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Activating coordinative conjugated polymer via interfacial electron transfer for efficient CO_(2) electroreduction
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作者 Jing Zhang Jia-Jun Dai +13 位作者 De-Quan Cao Heng Xu Xing-Yu Ding Chun-Hua Zhen Beate Paulus Jin-Yu Ye Qian Liang Jun-Ke Liu Shi-Jun Xie Sai-Sai Deng Zhen Wang Jun-Tao Li Yao Zhou Shi-Gang Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期313-323,I0009,共12页
With tunable local electronic environment,high mass density of MN4sites,and ease of preparation,metal-organic conjugated coordinative polymer(CCP) with inherent electronic conductivity provides a promising alternative... With tunable local electronic environment,high mass density of MN4sites,and ease of preparation,metal-organic conjugated coordinative polymer(CCP) with inherent electronic conductivity provides a promising alternative to the well-known M-N-C electrocatalysts.Herein,the coordination reaction between Cu^(2+)and 1,2,4,5-tetraaminobenzene(TAB) was conducted on the surface of metallic Cu nanowires,forming a thin layer of CuN4-based CCP(Cu-TAB) on the Cu nanowire.More importantly,interfacial transfer of electrons from Cu core to the CuN4-based CCP nanoshell was observed within the resulting CuTAB@Cu,which was found to enrich the local electronic density of the CuN4sites.As such,the CuTAB@Cu demonstrates much improved affinity to the*COOH intermediate formed from the rate determining step;the energy barrier for C-C coupling,which is critical to convert CO_(2)into C2products,is also decreased.Accordingly,it delivers a current density of-9.1 mA cm^(-2)at a potential as high as 0.558 V(vs.RHE) in H-type cell and a Faraday efficiency of 46.4% for ethanol.This work emphasizes the profound role of interfacial interaction in tuning the local electronic structure and activating the CuN4-based CCPs for efficient electroreduction of CO_(2). 展开更多
关键词 Metal-organic solid compounds Conjugated coordinative polymer Solid-solid interfacial electron transfer MN_(4)sites Electrocatalysis
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Influence of dye molecular structure on electron transfer in 2,9,16,23-tetracarboxy zinc phthalocyanine sensitized solar cell 被引量:1
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作者 王育乔 崔霞 +4 位作者 马艺文 祁昊楠 张慧君 张远 孙岳明 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期452-457,共6页
2, 9, 16, 23-tetracarboxy zinc phthalocyanine (ZnTCPc) is synthesized and characterized by physicochemical and theoretical methods and it is used as a photosensitizer in dye-sensitized solar cells (DSSC). The exci... 2, 9, 16, 23-tetracarboxy zinc phthalocyanine (ZnTCPc) is synthesized and characterized by physicochemical and theoretical methods and it is used as a photosensitizer in dye-sensitized solar cells (DSSC). The excited lifetime, band gap and frontier orbital distribution of ZnTCPc are investigated by fluorescence spectra, cyclic voltammetry and quantum calculation. The results show that the excited lifetime and band gap are 0. 1 ns and 1.81 eV, respectively. Moreover, it is found that the highest occupied molecular orbital (HOMO) location is not shared by both the zinc metal and the isoindoline ligands, and the lowest unoccupied molecular orbital(LUMO) location does not strengthen the interaction coupling between ZnTCPc and TiO:. As a result, the ZnTCPc-DSSC gains a short-circuit current density of 0. 147 mA/cm2, an open-circuit photovoltage of 277 mV, a fill factor of 0. 51 and an overall conversion efficiency of 0. 021%. 展开更多
关键词 zinc phthalocyanine solar cell frontier orbital electron transfer
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Theoretical Studies on the Mechanism of the Proton-transfer-coupled Electron Transfer Reactions Between Menaquinone Q_A and Ubiquinone Q_B in the Bacterial Photosynthetic Reaction Center of Rhodopseudomona viridis 被引量:1
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作者 马淑华 徐红 +3 位作者 张汝波 屈正旺 张兴康 张启元 《Acta Botanica Sinica》 CSCD 2002年第12期1409-1417,共9页
The mechanism of the proton_transfer_coupled electron transfer (PT_ET) reactions between the menaquinone Q A (MQ 1) and ubiquinone Q B (UQ 1) in the bacterial photosynthetic reaction center of Rhodopseudomona vi... The mechanism of the proton_transfer_coupled electron transfer (PT_ET) reactions between the menaquinone Q A (MQ 1) and ubiquinone Q B (UQ 1) in the bacterial photosynthetic reaction center of Rhodopseudomona viridis was studied by using the B3LYP/6_31G(d) method. The changes of standard Gibbs free energy ΔG 0 of all possible reactions followed the ET reaction (1) were calculated. The results indicated that: (1) according to the ΔG 0 values of corresponding reactions, UQ 1 could not accept two electrons from MQ - 1 continually without the coupled proton transfer reactions. Because of ΔG 0 2b 0, ΔG 0 3b 0 and ΔG 0 4b 0, the corresponding PT_ET reactions could take place along with reactions (2b), (3b) and (4b) sequentially; (2) on the gaseous condition, the first and second transferred protons (H +(1) and H +(2)) from the surrounding amino acid residues or water molecules will combine with the oxygen No.7 and oxygen No.8 of UQ 1, respectively. On the condition of protein surroundings (by SCRF model, ε =4.0), the results are converse but the energy difference between the combination of H +(1) and H +(2) with UQ - 1 is quite small. The difference of ΔG 0 values between the corresponding reactions in gaseous surroundings and the SCRF model is not significant; (3) the PT_ET reactions between MQ 1 - and UQ 1 - should be as follows: MQ 1 -+UQ 1→MQ 1+UQ 1 - (1) UQ 1 - ( O (7) )+H +( HisL 190)→UQ 1H(2b) ( Gas ) or UQ 1 - ( O (8) )+H +(H 2O)→UQ 1H (2b') ( SCRF ) or UQ 1 - ( O (8) )+H + ( ArgL 217)→UQ 1H(2b') ( SCRF ) MQ 1 -+UQ 1H→MQ 1+UQ 1H - (3b) ( Gas ) MQ 1 -+UQ 1H→MQ 1+UQ 1H -(3b') ( SCR F) UQ 1H -+H +(H 2O)→UQ 1H 2(4b) ( Gas ) or UQ 1H -+H + ( ArgL 217)→UQ 1H 2 (4b) ( Gas ) or UQ 1H -+H + ( HisL 190)→UQ 1H 2 (4b') ( SCRF ) 展开更多
关键词 Rhodopseudomena viridis electron transfer proton transfer Q A and Q B DFT
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Effects of Membrane Lipids on the Electron Transfer Activity of Cytochrome b_6f Complex from Spinach 被引量:1
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作者 阎久胜 毛大璋 +2 位作者 陈晖 匡廷云 李良璧 《Acta Botanica Sinica》 CSCD 2000年第12期1267-1270,共4页
A lipid_depleted cytochrome b 6f (Cyt b 6f) preparation was obtained from spinach (Spinacia oleracea L.) chloroplasts. Upon reconstitution of this preparation with the membrane lipids purified from spinach thylakoid... A lipid_depleted cytochrome b 6f (Cyt b 6f) preparation was obtained from spinach (Spinacia oleracea L.) chloroplasts. Upon reconstitution of this preparation with the membrane lipids purified from spinach thylakoid, the effects of different membrane lipids on the electron transfer activity were studied. The results show that the electron transfer activity of Cyt b 6f is obviously stimulated to different extents, respectively, by monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), phosphatidylcholine (PC), phosphatidylglycerol (PG) and sulfoquinovosyldiacylglycerol (SQDG), and that the extents of stimulation may be closely related to the charge of the membrane lipids. The stimulation of non_charged lipids (MGDG, DGDG) and neutrally_charged lipid (PC) was high with a maximum enhancement of 89%, 75% and 77%, respectively; but the stimulation of two kinds of negatively_charged lipid (PG and SQDG) was relatively low with a maximum enhancement of 43% and 26%, respectively. 展开更多
关键词 cytochrome b_(6)f complex thylakoid membrane lipid RECONSTITUTION electron transfer
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Photochemical Hydrogen Abstraction and Electron Transfer Reactions of Tetrachlorobenzoquinone with Pyrimidine Nucleobases
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作者 刘坤辉 吴丽丹 +3 位作者 邹笑然 杨文 杜谦 苏红梅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期580-585,I0004,共7页
Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photoc... Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photochemical reaction dynamics of TCBQ with two pyrimidine type nucleobases (thymine and uracil) upon UVA (355 ran) excitation using the technique of nanosecond time-resolved laser flash photolysis. It has been found that 355 nm excitation populates TCBQ molecules to their triplet state 3TCBQ*, which are highly reactive towards thymine or uracil and undergo two parallel reactions, the hydrogen abstraction and electron transfer, leading to the observed photoproducts of TCBQH. and TCBQ.- in transient absorption spectra. The concomitantly produced nucleobase radicals and radical cations are expected to induce a series of oxidative or strand cleavage damage to DNA afterwards. By characterizing the photochemical hydrogen abstraction and electron transfer reactions, our results provide potentially important molecular reaction mechanisms for understanding the carcinogenic effects of pentachlorophenol and its metabolites TCBQ. 展开更多
关键词 Tetrachlorobenzoquinone THYMINE URACIL Triplet state Hydrogen abstraction electron transfer Laser flash photolysis
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GaN based transfer electron and avalanche transit time devices
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作者 R.K.Parida A.K.Panda 《Journal of Semiconductors》 EI CAS CSCD 2012年第5期32-37,共6页
A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices(TEDs),namely a Gunn diode and an impact avalanche transit time(IMPATT) device.Microwave ch... A new model is developed to study the microwave/mm wave characteristics of two-terminal GaNbased transfer electron devices(TEDs),namely a Gunn diode and an impact avalanche transit time(IMPATT) device.Microwave characteristics such as device efficiency and the microwave power generated are computed and compared at D-band(140 GHz center frequency) to see the potentiality of each device under the same operating conditions.It is seen that GaN-based IMPATT devices surpass the Gunn diode in the said frequency region. 展开更多
关键词 GaN transfer electron device avalanche transit time device
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Electrons Transfer Between Mercaptoacetic Acid and ZnO Nanocrystal Thin Film 被引量:2
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作者 SHANGui-ye LUQiang +2 位作者 ANLi-min WANGXin BAIYu-bai 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第2期201-204,共4页
ZnO nanoorystals thin film were prepared by means of the self-assembly mothed. The complex films of mercaptoacetic acid(MPA) and ZnO nanocrystals(ZNCs) were prepared by means of the self-assembly technique. The intera... ZnO nanoorystals thin film were prepared by means of the self-assembly mothed. The complex films of mercaptoacetic acid(MPA) and ZnO nanocrystals(ZNCs) were prepared by means of the self-assembly technique. The interaction between the MPA and ZnO within the MPA and ZnO nanocrystal thin film decreases the photoluminescence intensity of the ZnO. The interaction was manifested by the X-ray photoelectron spectra. The intensity change of the photoluminescence of the ZnO is discussed on the basis of taking into account the process of electron transfer on the interface between the ZnO and MPA. The electron transfer of ZnO depends on the distance between the ZnO and MPA. 展开更多
关键词 ZNO Mercaptoacetic acid electron transfer
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Enhancing the dynamic electron transfer of Au species on wormhole-like TS-1 for boosting propene epoxidation performance with H_(2) and O_(2) 被引量:3
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作者 Dong Lin Xiuhui Zheng +7 位作者 Xiang Feng Nan Sheng Zhaoning Song Yibin Liu Xiaobo Chen Zhenping Cai De Chen Chaohe Yang 《Green Energy & Environment》 SCIE CSCD 2020年第4期433-443,共11页
Engineering unique electronic structure of catalyst to boost catalytic performance is of prime scientific and industrial importance.Herein,the identification of intrinsic electronic sensitivity for direct propene epox... Engineering unique electronic structure of catalyst to boost catalytic performance is of prime scientific and industrial importance.Herein,the identification of intrinsic electronic sensitivity for direct propene epoxidation was first achieved over highly stable Au/wormhole-like TS-1 catalyst.Results show that the electron transfer of Au species can be regulated by manipulating the dynamic evolutions and contents of Au valence states,thus resulting in different catalytic performance in 100 h time-on-stream.By DFT calculations,kinetic analysis and multicharacterizations,it is found that the Au^(0) species with higher electronic population can easily transfer more electrons to activate surface O_(2) compared with Au^(1+) and Au^(3+) species.Moreover,there is a positive correlation between Au^(0) content and activity.Based on this correlation,a facile strategy is further proposed to boost Au^(0) percentage,resulting in the reported highest PO formation rate without adding promoters.This work harbors tremendous guiding significance to the design of highly efficient Au/Ti-containing catalyst for propene epoxidation with H_(2) and O_(2). 展开更多
关键词 electron transfer Valence states Evolution Propene epoxidation DFT
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Carbon dots regulate the interface electron transfer and catalytic kinetics of Pt-based alloys catalyst for highly efficient hydrogen oxidation 被引量:4
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作者 Jie Wu Yunjie Zhou +6 位作者 Haodong Nie Kaiqiang Wei Hui Huang Fan Liao Yang Liu Mingwang Shao Zhenhui Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期61-67,I0003,共8页
The regulation of interface electron-transfer and catalytic kinetics is very important to design the efficient electrocatalyst for alkaline hydrogen oxidation reaction(HOR).Here,we show the Pt-Ni alloy nanoparticles(P... The regulation of interface electron-transfer and catalytic kinetics is very important to design the efficient electrocatalyst for alkaline hydrogen oxidation reaction(HOR).Here,we show the Pt-Ni alloy nanoparticles(PtNi_(2))have an enhanced HOR activity compared with single component Pt catalyst.While,the interface electron-transfer kinetics of PtNi_(2)catalyst exhibits a very wide electron-transfer speed distribution.When combined with carbon dots(CDs),the interface charge transfer of PtNi_(2)-CDs composite is optimized,and then the PtNi_(2)-5 mg CDs exhibits about 2.67 times and 4.04 times higher mass and specific activity in 0.1 M KOH than that of 20%commercial Pt/C.In this system,CDs also contribute to trapping H^(+)and H_(2)O generated during HOR,tuning hydrogen binding energy(HBE),and regulating interface electron transfer.This work provides a deep understanding of the interface catalytic kinetics of Pt-based alloys towards highly efficient HOR catalysts design. 展开更多
关键词 Pt-based alloys Carbon dots Interface electron transfer Interface catalytic kinetics Hydrogen oxidation reaction
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Combined pretreatment using CaO and liquid fraction of digestate of rice straw: Anaerobic digestion performance and electron transfer 被引量:5
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作者 Ruolin Guan Hairong Yuan +2 位作者 Liang Zhang Xiaoyu Zuo Xiujin Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期223-232,共10页
To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice stra... To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice straw with CaOLFD pretreatment was optimal in different pretreatment methods of the CaO+LFD,CaOLFD,LFD+CaO,CaO,and LFD.The maximum methane yield(314 ml(g VS)^(-1))and the highest VFAs concentration(14851 mg·L^(-1) on day 3)of the CaOLFD pretreatment group were 81%and 118%higher than that of the control group,respectively.Under the action of solid alkaline CaO,the bacteria of Clostridium,Atopostipes,Sphaerochaeta,Tissierella,Thiopseudomonas,Rikenellaceae,and Sedimentibacter could build up co-cultures with the archaeal of Methanosaeta,Methanobacterium,and Methanosarcina performing direct interspecies electron transfer(DIET)and improving AD performance of rice straw.Therefore,the combined pretreatment using CaO and LFD could not only pretreat rice straw but also stimulate co-cultures of microorganism to establish DIET enhancing AD efficiency. 展开更多
关键词 CaO-LFD pretreatment Direct interspecies electron transfer(DIET) Rice straw Anaerobic digestion(AD) Methane
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The ORR electron transfer kinetics control via Co-N_(x) and graphitic N sites in cobalt single atom catalysts in alkaline and acidic media 被引量:3
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作者 Tong Shen Xiaoxiao Huang +3 位作者 Shibo Xi Wei Li Shengnan Sun Yanglong Hou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期184-194,共11页
Cost-effective 3d transition metal(TM) based single atom catalysts(SACs) for oxygen reduction reaction(ORR) are potential alternatives for Pt-based electrocatalysts in fuel cells and metal-air batteries.Understanding ... Cost-effective 3d transition metal(TM) based single atom catalysts(SACs) for oxygen reduction reaction(ORR) are potential alternatives for Pt-based electrocatalysts in fuel cells and metal-air batteries.Understanding the effects of SACs’ properties and active site composition on the catalytic performance is significant to construct highly efficient catalysts. Here, we successfully promote the activity of cobalt single atoms decorated on N-doped carbon nanosheets via tuning the content of different nitrogen components, which outperforms most reported cobalt SACs. The activity and kinetics show positive correlation trends with the content of Co-Nxand graphitic N, serving as the main active sites.Furthermore, ORR kinetics in alkaline media can be positively affected by the conductivity of catalysts while no similar relation is observed in acidic media. The slight loss of Co-Nxsites engenders a mild change of performance in alkaline media, while the decrease of Co-Nxsite activity due to chemical oxidation of carbon support and the loss of Co-Nxsites in acidic media exacerbate the degradation of performance. Our work provides an insight into the relation between ORR electron transfer kinetics and active sites in 3d TM based SACs. 展开更多
关键词 Oxygen reduction reaction Single-atom electrocatalysts electron transfer kinetics Active sites Degradation mechanism
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Kinetics study of ultrafast electron transfer from sensitized dyes to silver halide microcrystals 被引量:1
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作者 杨少鹏 范国志 +4 位作者 范闪闪 曹宁 李晓苇 江晓利 傅广生 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期1055-1059,共5页
Spectral sensitization micromechanism of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr microcrystals with different dye concentrations is studied by using picosecond time-resolved fluorescence spectr... Spectral sensitization micromechanism of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr microcrystals with different dye concentrations is studied by using picosecond time-resolved fluorescence spectroscopy, and the dependences of electron transfer and spectral efficiency sensitization on different conditions are analysed in detail, With the steady spectroscopy, the wavelengths of absorption and fluorescence of J-aggregate adsorbed on AgBr microcrystals are found to shift to red relative to dye monomer. The spectrum of fluorescence has a red shift relative to the absorption peak. With the time-resolved fluorescence spectroscopy, the fluorescence decay curves of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr grains are found to be fitted well by a double-exponential decay function. The fitting curves consist of a fast and a slow component. Because of the large amplitude of the fast component, this fast decay should be attributable mainly to the electron transfer from J-aggregate of dye to a conduction band of AgBr. 展开更多
关键词 spectral sensitization electron transfer fluorescence lifetime silver bromide
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