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Concise synthesis of NDP-activated uronic acid by an oxidation reaction insertion strategy
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作者 Nana Yang Rui Yuan +5 位作者 Xinyue Fu Xiao Tian Jin Yu Shengzhou Ma Liuqing Wen Jiabin Zhang 《Chinese Chemical Letters》 2025年第8期296-302,共7页
Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uro... Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research. 展开更多
关键词 NDP-uronic acids BIOCATALYSIS Enzyme-mediated biomimetic synthesis oxidation reaction insertion strategy
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Tuning negative thermal expansion in Sm_(0.85)Zn_(0.15)MnO_(3−δ)via synthesis optimization for enhancing the stability of heterostructured solid oxide fuel cell cathodes 被引量:1
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作者 Jakub Fudalewski Piotr Winiarz Kun Zheng 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2689-2698,共10页
Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with ne... Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with negative thermal expansion(NTE)have at-tracted significant attention as effective additives for tailoring the thermomechanical properties of electrodes and enhancing cell durability.In this work,for the first time,single-phase NTE perovskite Sm_(0.85)Zn_(0.15)MnO_(3−δ)(SZM15)was successfully synthesized via the sol-gel method,eliminating the unwanted ZnO phase typically observed in materials obtained through the conventional solid-state reaction route.The sol-gel approach proved highly advantageous,offering low cost,robustness,excellent chemical homogeneity,precise compositional control,and high phase purity.After optimization of synthesis parameters,a negative TEC of approximately−6.5×10^(−6)K^(−1)was achieved in the 400-850℃range.SZM15 was then incorporated as an additive(10wt%-50wt%)into a SmBa0.5Sr0.5CoCuO_(5+δ)(SBSCCO)cathode to tune the thermomechanical properties with a La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3−δ)(LSGM)electrolyte,achieving a minimal TEC mismatch of only 1%.Notably,the SBSCCO+10wt%SZM15 composite cathode exhibited the lowest polarization resistance of 0.019Ω·cm^(2)at 900℃,showing approximately 70%lower than that of the pristine cathode.Excellent long-term stability after 100 h of operation was achieved.In addition,a high peak power density of 680 mW·cm^(−2)was achieved in a Ni-YSZ(yttria-stabilized zirconia)|YSZ|Ce_(0.9)Gd_(0.1)O_(2−δ)(GDC10)|SBSCCO+10wt%SZM15 anode-supported fuel cell at 850℃,highlighting the effectiveness of incorporating NTE materials as a promising strategy for regulating the thermomechanical properties and improving the long-term stability of intermediate temperature solid oxide fuel cells(IT-SOFCs). 展开更多
关键词 negative thermal expansion solid oxide fuel cell cathodes for solid oxide fuel cells sol-gel synthesis method
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One-Step Synthesis of a Pyrene Dimer with Intense Excimer Circularly Polarized Luminescence
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作者 Qing-Yu Meng Xiao-Fang Hou +6 位作者 Jia-Qi Zhao Jun-Qing Luo Wen-Kai Chen Zhimin Sun Jiao-Mei Cheng Xu-Man Chen He-Lue Sun 《Chinese Journal of Chemistry》 2025年第20期2655-2660,共6页
The development of circularly polarized luminescence (CPL) materials from simple organic molecules is of critical importance for advancing their practical applications, yet it remains hindered by challenges such as lo... The development of circularly polarized luminescence (CPL) materials from simple organic molecules is of critical importance for advancing their practical applications, yet it remains hindered by challenges such as low dissymmetry factors (glum) and complex synthetic process. Herein, we report a facile one-step [2+2] condensation strategy to access a Schiff-base pyrene dimer featuring 1,6-substituted pyrenes and trans-1,2-diaminocyclohexane units in 77% yield. Taking advantages of face-to-face π-π stacking of pyrene rings in the constrained D_(2) symmetric structure, intense excimer CPL was successfully realized with a |glum| value of 0.021 and a CPL brightness, BCPL, value of 154.5 M-1·cm-1. The optimized excited state structures reveal that the high |glum| value arises from the parallel arrangement of electric and magnetic dipole transition moments. Importantly, the rigid pyrene dimer architecture ensures robust CPL performance invariant under diverse conditions, including changes in temperature, concentration, and solvents, as well as in polymer films. 展开更多
关键词 Circularly polarized luminescence Pyrene dimer Pyrene excimer one-step synthesis Chiral macrocycle
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Electrochemically Driven Nickel-Catalyzed Phenol Synthesis via Sustainable Oxygen Atom Transfer from Nitrous Oxide
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作者 Qiyu Zhang Wenbin Xie +3 位作者 Yasser M.A.Mohamed Hossam A.El Nazer Ahmed A.Elnazer Yinghui Han 《Journal of Electronic Research and Application》 2025年第2期18-22,共5页
The valorization of nitrous oxide(N_(2)O)as an oxygen atom donor presents an attractive opportunity for green chemistry applications,leveraging both its industrial abundance and thermodynamically favorable oxidation p... The valorization of nitrous oxide(N_(2)O)as an oxygen atom donor presents an attractive opportunity for green chemistry applications,leveraging both its industrial abundance and thermodynamically favorable oxidation potential.However,practical implementation has been constrained by the inherent kinetic inertness and poor coordinating ability of N_(2)O.While prior studies achieved N_(2)O-mediated conversion of aryl halides to phenols,such transformations necessitated stoichiometric chemical reductants and elevated pressure(2 atm),posing challenges in operational safety and process scalability.This study focuses on an electrochemical strategy that enables efficient oxygen atom transfer under ambient pressure through controlled current application.This methodology facilitates the selective transformation of aryl iodides to phenols without external reducing agents,establishing an environmentally benign synthetic pathway.By replacing traditional chemical reductants with electrons as the sole reducing equivalent,our approach addresses critical sustainability challenges in aromatic oxygenation chemistry while maintaining operational simplicity under mild conditions. 展开更多
关键词 Nitrous oxide Electrochemical synthesis Aryl iodides Revalorization Nickel-catalysis
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Ligand-Driven Electron-Defcient Cobalt Pentlandite Nanocrystals for Effcient Hydrogen Peroxide Electrosynthesis
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作者 Jeong-Hyun Kim Jeong-Gyu Lee +1 位作者 Chang Seong Kim Min-Jae Choi 《Energy & Environmental Materials》 2025年第2期176-182,共7页
Cobalt pentlandite(Co9S8)is a promising non-precious catalyst due to its superior oxygen reduction reaction activity and excellent stability.However,its oxygen reduction reaction catalytic activity has traditionally b... Cobalt pentlandite(Co9S8)is a promising non-precious catalyst due to its superior oxygen reduction reaction activity and excellent stability.However,its oxygen reduction reaction catalytic activity has traditionally been limited to the four-electron pathway because of strong*OOH intermediate adsorption.In this study,we synthesized electron-deficient Co9S8 nanocrystals with an increased number of Co^(3+)states compared to conventional Co9S8.This was achieved by incorporating a high density of surface ligands in small-sized Co9S8nanocrystals,which enabled the transition of the electrochemical reduction pathway from four-electron oxygen reduction reaction to two-electron oxygen reduction reaction by decreasing*OOH adsorption strength.As a result,the Co^(3+)-enriched Co9S8 nanocrystals exhibited a high onset potential of 0.64 V(vs RHE)for two-electron oxygen reduction reaction,achieving H_(2)O_(2) selectivity of 70-80%over the potential range from 0.05 to 0.6 V.Additionally,these nanocrystals demonstrated a stable H_(2)O_(2) electrosynthesis at a rate of459.12 mmol g^(-1) h^(-1) with a H_(2)O_(2) Faradaic efficiency over 90%under alkaline conditions.This study provides insights into nanoscale catalyst design for modulating electrochemical reactions. 展开更多
关键词 cobalt pentlandite ELECTROCATALYSIS hydrogen peroxide synthesis oxidation state oxygen reduction reaction
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Synthesis and Application of Zero-Dimensional Metal Oxide Composites in Energy Chemistry
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作者 Runtian Hu 《Journal of Electronic Research and Application》 2025年第5期185-191,共7页
Against the backdrop of increasingly prominent global energy shortages and environmental issues,the development of efficient energy conversion and storage technologies has become crucial.Zero-dimensional(0D)metal oxid... Against the backdrop of increasingly prominent global energy shortages and environmental issues,the development of efficient energy conversion and storage technologies has become crucial.Zero-dimensional(0D)metal oxide composites exhibit significant application value in the field of energy chemistry due to their unique properties,such as quantum size effect and high specific surface area.From a broad perspective,this paper reviews the main synthesis methods of these composites,including sol-gel method,hydrothermal/solvothermal method,precipitation method,and template method,while analyzing the characteristics of each method.It further discusses their applications in photocatalytic hydrogen production,fuel cells,lithium-ion batteries,and supercapacitors.Additionally,the current challenges,such as material dispersibility and interface bonding,are pointed out,and future development directions are prospected,aiming to provide references for related research. 展开更多
关键词 Zero-dimensional metal oxide Composite material synthesis method Energy chemistry Energy conversion Energy storage
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Reusable salt-template strategy for synthesis of porous nitrogen-rich carbon boosts H_(2)S selective oxidation
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作者 Xu Liu Liang Shan +3 位作者 Xiaoxue Sun Tianxin Wang Zhongqing Liu Yuefeng Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第12期1866-1877,共12页
Removing hydrogen sulfide(H_(2)S)via the selective oxidation has been considered an effective way to further purify the indusial sulfurcontaining due to it can completely transform residual H_(2)S into elemental sulfu... Removing hydrogen sulfide(H_(2)S)via the selective oxidation has been considered an effective way to further purify the indusial sulfurcontaining due to it can completely transform residual H_(2)S into elemental sulfur.While N-doped porous carbon was applied to H_(2)S selective oxidation,a sustainable methodology for the synthesis of efficient and stable N-doped carbon catalysts remains a difficulty,limiting its future development in large-scale applications.Herein,we present porous,honeycomb-like N-doped carbon catalysts with large specific surface areas,high pyridinic N content,and numerous structural defects for H_(2)S selective oxidation prepared using reusable NaCl as the template.The asprepared NC-10-800 catalyst exhibits excellent catalytic performance(sulfur formation rate of 784 g_(sulfur) kg_(cat.)^(-1) h^(-1)),outstanding stability(>100 h),and excellent anti-water vapor,anti-CO_(2) and anti-oxidation properties,suggesting significant potential for practical industrial application.The characterization results and kinetic study demonstrate that the large surface areas and structural defects created by the molten salt at high temperature enhance the exposure of pyridinic N sites and thus accelerate the catalytic activity.Importantly,the water-soluble NaCl template could be easily washed from the carbon nanomaterials,and thus the downstream salt-containing wastewater could be subsequently reused for the dissolution of carbon precursors.This environment-friendly,low-cost,reusable salt-template strategy has significant implications for the development of N-doped carbon catalysts for practical applications. 展开更多
关键词 H_(2)S selective oxidation Nitrogen-doped carbon Reusable salt-template Green synthesis Porous carbon nanomaterials
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Achievable dual-strategy to stabilize Li-rich layered oxide interface by a one-step wet chemical reaction towards long oxygen redox reversibility 被引量:2
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作者 Bin He Yujie Dai +7 位作者 Shuai Jiang Dawei Chen Xilong Wang Jie Song Dan Xiao Qian Zhao Yan Meng Wei Feng 《Journal of Energy Chemistry》 2025年第2期120-131,I0004,共13页
Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capac... Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials. 展开更多
关键词 Lithium-rich layered oxide cathode one-step wet chemical reaction Surface coating Local gradient doping Interfacial oxygen
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Hollow cerium nanoparticles synthesized by one-step method for multienzyme activity to reduce colitis in mice
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作者 Lin Mi Kai Zhang +3 位作者 Jian-Xia Ma Jian-Feng Yao Yi-Li Tong Zhi-Jun Bao 《World Journal of Gastroenterology》 2025年第5期94-104,共11页
BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity ... BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of colitis.AIM To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in IBD.METHODS H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic activity.Subsequently,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic inflammation.The effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,respectively.Finally,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood biochemistry.RESULTS H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy mice.No significant damage to major organs was observed in healthy mice following H-CeO2 administration.CONCLUSION The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS. 展开更多
关键词 Inflammatory bowel disease Nanozymes Hollow cerium nanoparticles one-step method Cerium oxide biosafety
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Effects of Co_3O_4 nanocatalyst morphology on CO oxidation:Synthesis process map and catalytic activity 被引量:9
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作者 曾良鹏 李孔斋 +2 位作者 黄樊 祝星 李宏程 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期908-922,共15页
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy... This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies(i.e.,nanorods,nanosheets,and nanocubes) were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures(≤ 140℃).Nanorods can be synthesized in CoCl2 solution,while Co(NO3)2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature(higher than 140 ℃) results in the formation of nanocubes in either Co(NO3)2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^(3+) on the surface,much higher reducibility,and better oxygen desorption capacity. 展开更多
关键词 Cobalt oxide nanocatalyst synthesis process map Morphology effect Catalytic activity Carbon monoxide oxidation
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Machine learning in electrochemical oxidation process:A mini-review
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作者 Zonglin Li Shihua Zou +3 位作者 Zining Wang Georgeta Postole Liang Hu Hongying Zhao 《Chinese Chemical Letters》 2025年第8期28-38,共11页
In recent years,machine learning(ML)techniques have demonstrated a strong ability to solve highly complex and non-linear problems by analyzing large datasets and learning their intrinsic patterns and relationships.Par... In recent years,machine learning(ML)techniques have demonstrated a strong ability to solve highly complex and non-linear problems by analyzing large datasets and learning their intrinsic patterns and relationships.Particularly in chemical engineering and materials science,ML can be used to discover microstructural composition,optimize chemical processes,and create novel synthetic pathways.Electrochemical processes offer the advantages of precise process control,environmental friendliness,high energy conversion efficiency and low cost.This review article provides the first systematic summary of ML in the application of electrochemical oxidation,including pollutant removal,battery remediation,substance synthesis and material characterization prediction.Hot trends at the intersection of ML and electrochemical oxidation were analyzed through bibliometrics.Common ML models were outlined.The role of ML in improving removal efficiency,optimizing experimental conditions,aiding battery diagnosis and predictive maintenance,and revealing material characterization was highlighted.In addition,current issues and future perspectives were presented in relation to the strengths and weaknesses of ML algorithms applied to electrochemical oxidation.In order to further support the sustainable growth of electrochemistry from basic research to useful applications,this review attempts to make it easier to integrate ML into electrochemical oxidation. 展开更多
关键词 Machine learning Electrochemical oxidation Pollutant removal Lithium-ion battery Material synthesis
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Hepatic SIRT6 protects against cholestatic liver disease primarily via inhibiting bile acid synthesis
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作者 Wen Zhang Jiahui Wang +4 位作者 Luyao Yang Yuyun Shao Hongjun Peng Longfeng Jiang Liang Sheng 《Journal of Biomedical Research》 2025年第4期340-355,I0002,I0003,共18页
Cholestatic liver disease,caused by the accumulation of hazardous bile acids in the liver,may result in cirrhosis,fibrosis,or liver failure.Activation of sirtuin 6(SIRT6)prevents cholestasis-associated pathological ev... Cholestatic liver disease,caused by the accumulation of hazardous bile acids in the liver,may result in cirrhosis,fibrosis,or liver failure.Activation of sirtuin 6(SIRT6)prevents cholestasis-associated pathological events,such as oxidative stress and mitochondrial biogenesis dysfunction,and inhibits bile acid synthesis to alleviate cholestatic liver injury.However,it remains uncertain which pathway mediates the therapeutic effect of SIRT6 in reducing cholestasis.Therefore,we treated liver-specific Sirt6 knockout mice with N-acetylcysteine,KEAP1-NRF2-IN-1,or acadesine to alleviate oxidative stress and/or promote mitochondrial biogenesis after modeling cholestatic liver disease,but these measures did not significantly improve cholestatic symptoms.However,MDL801,a SIRT6 agonist that downregulates cholesterol 7α-hydroxylase(CYP7A1,the key enzyme in bile acid synthesis)levels,exhibited favorable therapeutic effects.Additionally,the hepatic knockdown of Cyp7a1 further demonstrated that inhibiting hepatic bile acid synthesis might be the main pathway through which SIRT6 alleviates cholestatic liver disease.These findings provide a solid basis for the potential application of SIRT6 agonists in treating cholestatic liver disease. 展开更多
关键词 sirtuin 6 cholestatic liver disease oxidative stress mitochondrial biogenesis bile acid synthesis
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Ultrafast synthesis of nanocrystalline spinel oxides by Joule-heating method
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作者 Wenxuan Yang Long Shang +4 位作者 Xiaomeng Liu Sihan Zhang Haixia Li Zhenhua Yan Jun Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期517-521,共5页
Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to t... Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to the structure designments while methods are often energy-intensive and inefficient.Here,we devised a universal strategy to achieve rapid synthesis of nanocrystalline spinel materials with multiple components(Co_(3)O_(4),Mn_(3)O_(4),CoMn_(2)O_(4)and CoFe_(2)O_(4)are as examples),where phase formation is within 15 s.Under the Joule-heating shock,a crack-break process of microcosmic phase transformation is observed by in-situ transmission electron microscopy.The half-wave potential values of Co_(3)O_(4)-JH,Mn_(3)O_(4)-JH,CoMn_(2)O_(4)-JH and CoFe_(2)O_(4)-JH in the electrocatalytic oxygen reduction reaction were 0.77,0.78,0.79 and 0.76,respectively.This suggests that the Joule heating is a fast and efficient method for the preparation of spinel oxide electrocatalysts. 展开更多
关键词 Ultrafast synthesis Spinel oxides Joule-heating In-situ TEM Oxygen reduction
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CeO_2 as the Oxygen Carrier for Partial Oxidation of Methane to Synthesis Gas in Molten Salts: Thermodynamic Analysis and Experimental Investigation 被引量:14
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作者 Yonggang Wei Hua Wang Fang He Xianquan Ao Chiyuan Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期6-11,共6页
A new technique -- the direct partial oxidation of methane to synthesis gas using lattice oxygen in molten salts medium has been introduced. Using CeO2 as the oxygen carrier, thermodynamic data were calculated in the ... A new technique -- the direct partial oxidation of methane to synthesis gas using lattice oxygen in molten salts medium has been introduced. Using CeO2 as the oxygen carrier, thermodynamic data were calculated in the reaction process, and the results indicated that direct partial oxidation of methane to synthesis gas using lattice oxygen of cerium oxide is feasible in theory. In a stainless steel reactor, the effects of temperature and varying amounts of γ-Al2O3 supported CeO2 on cn4 conversion, H2 and CO selectivity, were investigated, respectively. The results show that 10% CeO2/γ-Al2O3 has the maximal reaction activity at a temperature of 865 ℃ and above, the H2/CO ratio in the gas that has been produced reaches 2 and the CH4 conversion, H2 and CO selectivity reached the following percentages: i.e. 61%, 89%, and 91% at 870 ℃, respectively. In addition, increase of reaction temperature is favorable for the partial oxidation of methane. 展开更多
关键词 partial oxidation METHANE cerium oxide synthesis gas molten salt
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Synthesis of mesoporous CeO_2-MnO_x binary oxides and their catalytic performances for CO oxidation 被引量:9
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作者 詹望成 张欣烨 +3 位作者 郭杨龙 王丽 郭耘 卢冠忠 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第2期146-152,共7页
Mesoporous CeO2-MnOx binary oxides with different Mn/Ce molar ratios were prepared by hydrothermal synthesis and characterized by scanning electron microscopy (SEM), N2 sorption, X-ray diffraction (XRD), X-ray pho... Mesoporous CeO2-MnOx binary oxides with different Mn/Ce molar ratios were prepared by hydrothermal synthesis and characterized by scanning electron microscopy (SEM), N2 sorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and H2 temperature-programmed reduction (H2-TPR). The characterization results indicated that the CeO2-MnOx catalysts exhibited flower-like microspheres with high specific surface areas, and partial Mn cations could be incorporated into CeO2 lattice to form solid solution. The CeO2-MnOx catalysts showed better catalytic activity for CO oxidation than that prepared by the coprecipitation method. Furthermore, the CeO2-MnOx catalyst with Mn/Ce molar ratio of 1 in the synthesis gel (Ce-Mn-1) exhibited the best catalytic activity, over which the conversion of CO could achieve 90% at 135 ℃. This was ascribed to presence of more Mn species with higher oxida- tion state on the surface and the better reducibility over the Ce-Mn-I catalyst than other CeO2-MnOx catalysts. 展开更多
关键词 mesoporous composite oxides CERIA manganese oxide hydrothermal synthesis CO oxidation rare earths
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Methane Oxidation to Synthesis Gas Using Lattice Oxygen of La_(1-x)Sr_xMO_(3-λ)(M =Fe,Mn) Perovskite Oxides Instead of Molecular Oxygen 被引量:10
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作者 LiRanjia YuChangchun ZhuGuangrong ShenShikong 《Petroleum Science》 SCIE CAS CSCD 2005年第1期19-23,共5页
In this paper, the partial oxidation of methane to synthesis gas using lattice oxygen of La1- SrxMO3-λ (M=Fe, x ... In this paper, the partial oxidation of methane to synthesis gas using lattice oxygen of La1- SrxMO3-λ (M=Fe, x Mn) perovskite oxides instead of molecular oxygen was investigated. The redox circulation between 11% O2/Ar flow and 11% CH4/He flow at 900℃ shows that methane can be oxidized to CO and H2 with a selectivity of over 90.7% using the lattice oxygen of La1- SrxFeO3-λ (x≤0.2) perovskite oxides in an appropriate reaction condition, while the lost lattice x oxygen can be supplemented by air re-oxidation. It is viable for the lattice oxygen of La1- SrxFeO3-λ (x≤0.2) perovskite x oxides instead of molecular oxygen to react with methane to synthesis gas in the redox mode. 展开更多
关键词 Partial oxidation METHANE synthesis gas lattice oxygen La1- xSrxFeO3-λperovskite oxides
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Synthesis of cerium-doped MCM-48 molecular sieves and its catalytic performance for selective oxidation of cyclohexane 被引量:8
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作者 詹望成 卢冠忠 +5 位作者 郭杨龙 郭耘 王艳芹 王筠松 张志刚 刘晓晖 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第4期515-522,共8页
Cerium-doped MCM-48 molecular sieves were synthesized hydrothermally and characterized by X-ray diffraction, nitrogen adsorption, transmission electron microscope, FT-IR spectroscopy, UV-visible spectroscopy, and Rama... Cerium-doped MCM-48 molecular sieves were synthesized hydrothermally and characterized by X-ray diffraction, nitrogen adsorption, transmission electron microscope, FT-IR spectroscopy, UV-visible spectroscopy, and Raman spectroscopy. The results showed that all the samples held the structure of MCM-48, and Ce could enter the framework of MCM-48. However, when Ce/Si molar ratio in the sampies was high (0.04 or 0.059), there were CeO2 crystallites as secondary phase in the extraframework of MCM-48. Ce-doped MCM-48 was a very efficient catalyst for the oxidation of cyclohexane in a solvent-free system with oxygen as an oxidant. In the conditions of 0.5 MPa 02 and 413 K for 5 h, the conversion of cyclohexane was 8.1% over Ce-MCM-48-0.02, the total selectivity of cyclohexanol and cyclohaxnone was 98.7%. With an increase of Ce content, the conversion of cyclohexane and the selectivity to cyclohexanol decreased somewhat, but the selectivity to cyclohexanone increased. 展开更多
关键词 Ce-doped MCM-48 synthesis CYCLOHEXANE catalytic oxidation rare earths
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"Green synthesis of zinc oxide nanoparticles:Eco-friendly advancements for biomedical marvels"
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作者 Nandhini J Karthikeyan E Rajeshkumar S 《Resources Chemicals and Materials》 2024年第4期294-316,共23页
This article explores an in-depth analysis of eco-friendly green synthesis methods to manufacture zinc oxide nanoparticles(ZnO NPs).Although chemical and/or physical approaches may initially provide better results;in ... This article explores an in-depth analysis of eco-friendly green synthesis methods to manufacture zinc oxide nanoparticles(ZnO NPs).Although chemical and/or physical approaches may initially provide better results;in the long term;a biological approach using green or natural pathways using plant extracts;enzymes;and mi-crobes may be eco-friendly and more cost-effective.This review addresses various green synthesis techniques and their potential biomedical applications;elucidating their mechanisms.Additionally;the article highlights the pivotal role of ZnO NPs in diabetes;cancer;wound healing;drug delivery;and other biomedical marvels.Overall;it highlights the importance of green-synthesized ZnO NPs in building a future of sustainable biomedical breakthroughs. 展开更多
关键词 Zinc oxide nanoparticles Green synthesis ANTIMICROBIAL Drug delivery Anti-cancer and biomedical applications
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One-step synthesis of Fe-Ni hydroxide nanosheets derived from bimetallic foam for efficient electrocatalytic oxygen evolution and overall water splitting 被引量:7
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作者 Lili Zeng Linjing Yang +5 位作者 Jia Lu Jin Jia Jiayuan Yu Yunqie Deng Mingfei Shao Weijia Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第12期1875-1878,共4页
The research of superior water oxidation electrodes is essential for the green energy in the form of hydrogen by way of electrolytic water splitting, and still remains challenging. Based upon dealloying foam, Fe-Ni hy... The research of superior water oxidation electrodes is essential for the green energy in the form of hydrogen by way of electrolytic water splitting, and still remains challenging. Based upon dealloying foam, Fe-Ni hydroxide nanosheets network structure is designed on the surface of Fe-Ni alloy foam. The ratio of Ni/Fe elements was adjusted to realize the optimal catalytic activities for oxygen evolution reaction(OER) and hydrogen evolution reaction(HER). The obtained electrode of Fe-Ni hydroxide nanosheets/Fe-Ni alloy foam-60% Fe(FN LDH/FNF-60, 60 is the percentage of Fe content) possess low overpotential of 261 mV to reach 10 mA/cm;, small Tafel slope(85.5 mV/dec), and superior long-term stability(remaining 10 mA/cm;for over 14 h without attenuation) toward OER in 1.0 mol/L KOH.Moreover, an alkaline water electrolyzer is constructed with the FN LDH/FNF-60 as anode and Ni(OH);/Fe-Ni alloy foam-25% Fe(Ni(OH);/FNF-25) as cathode, which displays superior electrolytic performance(affording 10 mA/cm;at 1.62 V) and lasting durability. 展开更多
关键词 one-step synthesis Bimetallic foam Water splitting Fe-Ni hydroxide Nanosheet array
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Crown ether-appended Fe(Ⅲ) porphyrin:Synthesis,characterization and catalytic oxidation of cyclohexene with molecular oxygen 被引量:4
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作者 Xiao Dong Li Yuan Cheng Zhu Ling Juan Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第3期375-378,共4页
A new crown ether appended Fe(Ⅲ) porphyrin complex was prepared by sulfuryl chloride appended benzo-15-crown-5 to the meso position of meso-5,10,15,20-tetra(4-hydrophenyl)porphyrin,and it was applied to catalytic... A new crown ether appended Fe(Ⅲ) porphyrin complex was prepared by sulfuryl chloride appended benzo-15-crown-5 to the meso position of meso-5,10,15,20-tetra(4-hydrophenyl)porphyrin,and it was applied to catalytic oxidation of cyclohexene with molecular oxygen without reductant,showing a remarkable catalytic activity(conversion is up to 94%) and selectivity for 2-cyclohexen-1-ol(73%). 展开更多
关键词 Crown ether-appended Fe(Ⅲ) porphyrin synthesis Catalytic oxidation CYCLOHEXENE Molecular oxygen
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