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Cardioprotective Potential of Cymbopogon citratus Essential Oil against Isoproterenol-induced Cardiomyocyte Hypertrophy:Possible Involvement of NLRP3 Inflammasome and Oxidative Phosphorylation Complex Subunits
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作者 Xiao-yun DING Hao ZHANG +7 位作者 Yu-mei QIU Meng-die XIE Hu WANG Zheng-yu XIONG Ting-ting LI Chun-ni HE Wei DONG Xi-lan TANG 《Current Medical Science》 SCIE CAS 2024年第2期450-461,共12页
Objective:Cymbopogon citratus(DC.)Stapf is a medicinal and edible herb that is widely used for the treatment of gastric,nervous and hypertensive disorders.In this study,we investigated the cardioprotective effects and... Objective:Cymbopogon citratus(DC.)Stapf is a medicinal and edible herb that is widely used for the treatment of gastric,nervous and hypertensive disorders.In this study,we investigated the cardioprotective effects and mechanisms of the essential oil,the main active ingredient of Cymbopogon citratus,on isoproterenol(ISO)-induced cardiomyocyte hypertrophy.Methods:The compositions of Cymbopogon citratus essential oil(CCEO)were determined by gas chromatography-mass spectrometry.Cardiomyocytes were pretreated with 16.9µg/L CCEO for 1 h followed by 10µmol/L ISO for 24 h.Cardiac hypertrophy-related indicators and NLRP3 inflammasome expression were evaluated.Subsequently,transcriptome sequencing(RNA-seq)and target verification were used to further explore the underlying mechanism.Results:Our results showed that the CCEO mainly included citronellal(45.66%),geraniol(23.32%),and citronellol(10.37%).CCEO inhibited ISO-induced increases in cell surface area and protein content,as well as the upregulation of fetal gene expression.Moreover,CCEO inhibited ISO-induced NLRP3 inflammasome expression,as evidenced by decreased lactate dehydrogenase content and downregulated mRNA levels of NLRP3,ASC,CASP1,GSDMD,and IL-1β,as well as reduced protein levels of NLRP3,ASC,pro-caspase-1,caspase-1(p20),GSDMD-FL,GSDMD-N,and pro-IL-1β.The RNA-seq results showed that CCEO inhibited the increase in the mRNA levels of 26 oxidative phosphorylation complex subunits in ISO-treated cardiomyocytes.Our further experiments confirmed that CCEO suppressed ISO-induced upregulation of mt-Nd1,Sdhd,mt-Cytb,Uqcrq,and mt-Atp6 but had no obvious effects on mt-Col expression.Conclusion:CCEO inhibits ISO-induced cardiomyocyte hypertrophy through the suppression of NLRP3 inflammasome expression and the regulation of several oxidative phosphorylation complex subunits. 展开更多
关键词 Cymbopogon citratus essential oil cardiac hypertrophy NLRP3 inflammasome oxidative phosphorylation complex subunits
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Preparation and characterization of Ce_(1-x)Fe_xO_2 complex oxides and its catalytic activity for methane selective oxidation 被引量:7
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作者 李孔斋 王华 +1 位作者 魏永刚 刘明春 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期245-249,共5页
A series of Ce1-xFexO2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) complex oxide catalysts were prepared using the coprecipitation method. The catalysts were characterized by means of XRD and H2-TPR. The reactions between methane ... A series of Ce1-xFexO2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) complex oxide catalysts were prepared using the coprecipitation method. The catalysts were characterized by means of XRD and H2-TPR. The reactions between methane and lattice oxygen from the complex oxides were investigated. The characteristic results revealed that the combination of Ce and Fe oxide in the catalysts could lower the temperature necessary to reduce the cerium oxide. The catalytic activity for selective CH4 oxidation was strongly influenced by dropped Fe species. Adding the appropriate amount of Fe2O3 to CeO2 could promote the action between CH4 and CeO2. Dispersed Fe2O3 first returned to the original state and would then virtually form the Fe species on the catalyst, which could be considered as the active site for selective CH4 oxidation. The appearance of carbon formation was significant and the oxidation of carbon appeared to be the rate-determining step; the amounts of surface reducible oxygen species in CeO2 were also relevant to the activity. Among all the catalysts, Ce0.6Fe0.402 exhibited the best activity, which converted 94.52% of CH4 at 900 ℃. 展开更多
关键词 Ce1-xFexO2 complex oxides H2-TPR lattice oxygen methane selective oxidation rare earths
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Catalytic performance of cerium iron complex oxides for partial oxidation of methane to synthesis gas 被引量:2
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作者 李孔斋 王华 +1 位作者 魏永刚 刘明春 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第5期705-710,共6页
The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. Th... The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. The reduced oxygen carder could be re-oxidized by air and its initial state could be restored. The characterizations of the oxygen carders were studied using XRD, O2-TPD, and H2-TPR. The results showed that the bulk lattice oxygen of CeO2-Fe2O3 was found to be suitable for the partial oxidation of methane to synthesis gas. There were two kinds of oxygen species on the oxygen carrier: the stronger oxygen species that was responsible for the complete oxidation of methane, and the weaker oxygen species (bulk lattice oxygen) that was responsible for the selective oxidation of methane to CO and H2 at a higher temperature. Then, the lost bulk lattice oxygen could be selectively supplemented by air re-oxidation at an appropriate reaction condition. CeFeO3 appeared on the oxygen carrier after 10 successive redox cycles, however, it was not bad for the selectivity of CO and H2. 展开更多
关键词 METHANE cerium iron complex oxides lattice oxygen selective oxidation SYNGAS cycles rare earths
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Synthesis and Electrocatalytic Properties of Complex Oxides Containing Lanthanum 被引量:2
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作者 林纪筠 赵孟科 陈康宁 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期231-233,共3页
A series of perovskite-type complex oxides LaNi1-xRuxO3 were prepared and studied by means of XRD. The effects of some factors on th complex oxides were discussed. Each kind of those perovskite-type complex oxides was... A series of perovskite-type complex oxides LaNi1-xRuxO3 were prepared and studied by means of XRD. The effects of some factors on th complex oxides were discussed. Each kind of those perovskite-type complex oxides was used to prepare cathode by composite-electroplating technique. The cathodes were electrochemically charactrized. The results show that these novel cathode exhibit high activities and excellent stabilities during long-term continuous electrolysis with some current interruptions. 展开更多
关键词 rare earths LANTHANUM NICKEL perovskite complex oxides active cathodes
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Eu(Ⅲ) complexes involving 1,3,5-triazine diphosphine oxides 被引量:1
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作者 O.Pietraszkiewicz M.Pietraszkiewicz +1 位作者 J.Karpiuk M.Jesień 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第4期584-587,共4页
The 1,3,5-triazine diphosphine oxide ligands with donor-acceptor properties formed strong complexes with europium(Ⅲ) ion in acetonitrile. Spectrophotometric titrations and mass spectra indicated that two ligands co... The 1,3,5-triazine diphosphine oxide ligands with donor-acceptor properties formed strong complexes with europium(Ⅲ) ion in acetonitrile. Spectrophotometric titrations and mass spectra indicated that two ligands coordinated to one europium ion. The stability constants varied from 11.64 to 14.60 (log 13). Binary complexes exhibited rather weak luminescence in solution. 1,3,5-triazine diphosphine oxides engaged as co-ligands in Eu(Ⅲ) (2-thenoyltrifluoroacetonate)3 complex contributed to the overall photoluminescence and allowed for excitation with longer wavelengths than the parent complex. 展开更多
关键词 Eu(Ⅲ) complexes 1 3 5-TRIAZINE diphosphine oxide SPECTROSCOPY rare earths
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Metal–Oleate Complex?Derived Bimetallic Oxides Nanoparticles Encapsulated in 3D Graphene Networks as Anodes for Efficient Lithium Storage with Pseudocapacitance 被引量:1
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作者 Yingying Cao Kaiming Geng +6 位作者 Hongbo Geng Huixiang Ang Jie Pei Yayuan Liu Xueqin Cao Junwei Zheng Hongwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第1期250-263,共14页
In this manuscript, we have demonstrated the delicate design and synthesis of bimetallic oxides nanoparticles derived from metal–oleate complex embedded in 3D graphene networks(MnO/CoMn_2O_4  GN), as an anode mater... In this manuscript, we have demonstrated the delicate design and synthesis of bimetallic oxides nanoparticles derived from metal–oleate complex embedded in 3D graphene networks(MnO/CoMn_2O_4  GN), as an anode material for lithium ion batteries. The novel synthesis of the MnO/CoMn_2O_4  GN consists of thermal decomposition of metal–oleate complex containing cobalt and manganese metals and oleate ligand, forming bimetallic oxides nanoparticles, followed by a selfassembly route with reduced graphene oxides. The MnO/CoMn_2O_4  GN composite, with a unique architecture of bimetallic oxides nanoparticles encapsulated in 3D graphene networks, rationally integrates several benefits including shortening the di usion path of Li^+ ions, improving electrical conductivity and mitigating volume variation during cycling. Studies show that the electrochemical reaction processes of MnO/Co Mn_2O_4  GN electrodes are dominated by the pseudocapacitive behavior, leading to fast Li^+ charge/discharge reactions. As a result, the MnO/CoMn_2O_4  GN manifests high initial specific capacity, stable cycling performance, and excellent rate capability. 展开更多
关键词 Metal–oleate complex Bimetallic oxides NANOPARTICLES Porous architecture 3D GRAPHENE NETWORKS Lithium ion batteries
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Study of engineering electronic structure modulated non-noble metal oxides for scaled-up alkaline blend seawater splitting
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作者 Natarajan Logeshwaran Subramanian Vijayapradeep +5 位作者 Ae Rhan Kim Prabhakaran Sampath Shanmugam Ramakrishnan Milan Babu Poudel Do Hwan Kim Dong Jin Yoo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期167-179,I0004,共14页
Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a sig... Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production. 展开更多
关键词 Waterel ectrolysis Mn-Ni oxide complex Chlorine evolution reaction Industrial seawater operations Density functional theory calculations
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Mass Transfer-Promoted Fe^(2+)/Fe^(3+)Circulation Steered by 3D Flow-Through Co-Catalyst System Toward Sustainable Advanced Oxidation Processes
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作者 Weiyang Lv Hao Li +6 位作者 Jinhui Wang Lixin Wang Zenglong Wu Yuge Wang Wenkai Song Wenkai Cheng Yuyuan Yao 《Engineering》 SCIE EI CAS CSCD 2024年第5期264-275,共12页
Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-c... Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-catalysts still suffer from the poor mass/electron transfer and non-durable promotion effect,giving rise to the sluggish Fe^(2+)/Fe^(3+)cycle and low dynamic concentration of Fe^(2+)for ROS production.Herein,we present a three-dimensional(3D)macroscale co-catalyst functionalized with molybdenum disulfide(MoS_(2))to achieve ultra-efficient Fe^(2+)regeneration(equilibrium Fe^(2+)ratio of 82.4%)and remarkable stability(more than 20 cycles)via a circulating flow-through process.Unlike the conventional batch-type reactor,experiments and computational fluid dynamics simulations demonstrate that the optimal utilization of the 3D active area under the flow-through mode,initiated by the convectionenhanced mass/charge transfer for Fe^(2+)reduction and then strengthened by MoS_(2)-induced flow rotation for sufficient reactant mixing,is crucial for oxidant activation and subsequent ROS generation.Strikingly,the flow-through co-catalytic system with superwetting capabilities can even tackle the intricate oily wastewater stabilized by different surfactants without the loss of pollutant degradation efficiency.Our findings highlight an innovative co-catalyst system design to expand the applicability of AOPs based technology,especially in large-scale complex wastewater treatment. 展开更多
关键词 Advanced oxidation processes 3D co-catalyst Flow-through mode Enhanced mass transfer complex wastewater treatment
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Mg/Al complex oxides-A new type of solid basic catalyst for epoxidation
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作者 Heng Miao Shi-Chao Xu +7 位作者 Hai-Nan Wang Wen-Xia Qin Lin Lin Zhang Ji-Mei Zhang Juan Yang Zhao Dai Guo Zheng En-Qi Tang 《Journal of Biomedical Science and Engineering》 2010年第2期213-216,共4页
Hydrotalcites known as anionic clays are found in nature. Hydrotalcites, hydrotalcite-like compounds, and calcined hydrotalcites (as mixed or complex oxides) as highly active, selective catalysts play an important rol... Hydrotalcites known as anionic clays are found in nature. Hydrotalcites, hydrotalcite-like compounds, and calcined hydrotalcites (as mixed or complex oxides) as highly active, selective catalysts play an important role in many base/catalyzed reactions. Mg/Al hydrotalcite (MAH) as precursor was used to prepare Mg/Al metal complex oxides (MAO), used as epoxidation catalysts in the current research. In this paper, some primary physical and catalytic properties of MAH and MAO were investigated. The results indicated that the qualified MAH (Mg/Al mol ratio of 3) can be achieved when the suspension was crystallized under 80°C for 16h, and after being filtered, dried at 100 °C for 5h in a oven. MAO was prepared by calcining MAH for 4h in a muffle furnace, and calcination temperature was determined to be 500 °C by a differential scanning calorimeter (DSC). Crystal structure and parameters of MAH and MAO were characterized by X/ray diffraction (XRD), good crystal structure was observed and typical peaks of MAH were detected when 2θ was at 11.5 (003), 23.0 (006), 35.0 (009), and 61.0 (110), respectively. The morphology of calcined precursor, i.e. MAO, was investigated with scanning electron microscopy (SEM);the finer lamellar structure and smaller average size of 3μm was observed. Molding research was performed and confirmed by SEM, the results indicated that the surface bulge and cavity with size of several micrometers were increased, which simultaneously suggested the increasing of specific surface area. The catalytic activity of molding MAO was finally examined by using octanol as starting reagent and ethylene oxide as reactant, and narrower molecular distribution was observed comparing with the traditional catalyst-KOH. 展开更多
关键词 Mg/Al HYDROTALCITES Mg/Al Metal complex oxides MOLDING EPoxidATION
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A Band Theory Perspective on Molecular Orbitals in Complex Oxides
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作者 Kateryna Foyevtsova George A. Sawatzky 《Journal of Modern Physics》 2019年第8期953-965,共13页
In view of the growing interest in molecular orbitals (MOs) encountered in certain complex oxides, we review some of their properties from the band theory perspective and provide detailed examples based on real materi... In view of the growing interest in molecular orbitals (MOs) encountered in certain complex oxides, we review some of their properties from the band theory perspective and provide detailed examples based on real materials. Our discussion includes some technical aspects of identifying MOs in electronic structure calculations and considers cases when MOs can be both orthogonal and non-orthogonal. We also describe orthonormalization of MOs, a procedure converting them into Wannier functions, and discuss the problem of Wannier functions possibly being rather spatially extended and how using MO, rather than atomic orbital, based effective Hamiltonians might be a better choice in describing certain strongly correlated systems as well as systems with strong electron-phonon coupling. Furthermore, we address the problem of strongly correlated MOs and how it can be treated in band theory calculations. 展开更多
关键词 Electronic Structure of SOLIDS MOLECULAR ORBITALS complex oxides NEGATIVE CHARGE-TRANSFER Insulators
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Preparations of Complex Bimetallic Oxides from Bimetallic Assemblies Containing Different Copper(Ⅱ) Precursors and Comparison of Some Related Systems
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作者 Masaki Kobayashi Satoshi Ehara Naoshi Hayashi Satoru Sonoki Takashiro Akitsu 《Journal of Chemistry and Chemical Engineering》 2014年第7期647-653,共7页
This is a mini-review-like article including our recent results and methods for (new) metal oxides and (previously reported) composite materials composed of metal complexes and metal oxides for comparison to enhan... This is a mini-review-like article including our recent results and methods for (new) metal oxides and (previously reported) composite materials composed of metal complexes and metal oxides for comparison to enhance anisotropic structural changes intentionally. Some complex inorganic oxides are known that they may be promising color materials (absorbing visible light of certain wavelengths region) having potential application for environmentally benign catalysts, for example, photocatalysts. Chiral copper(Ⅱ) complexes having bidentate amine ligands ([CuL2]2+) can be acted as cationic building blocks of bimetallic metal complexes. We have prepared some chiral bimetallic complexes with various anionic metal complexes such as [PtCl4]2-, [M02O7]2 and Mn12 clusters (typical single-molecule magnets) which characterized by means of solid-state electronic and CD (circular dichroism) spectra, IR (infrared) spectra, synchrotron XRD (X-ray diffraction) and XAS (soft X-ray absorption spectroscopy). By sintering these precursor chiral bimetallic complexes, we have prepared complex inorganic oxides from them. The IR spectra indicated substituting metal-ligand bonds and losing organic moieties. The XRD pattern indicated complete changes of crystal structures. The XAS revealed replacing coordination atoms as well as oxidation of valences of metal ions. Furthermore, we will also investigate possibility of patterning by homogeneous precipitation method as bimetallic complexes to prepare desirable complex inorganic oxides. 展开更多
关键词 Metal oxides metal complexes XRD structural changes anisotropy.
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SPECTRAL VARIATION AND CHARACTERISTICS OF LOW VALENCY RARE EARTH IONS IN COMPLEX OXIDESⅢ.EFFECT OF THE CRYSTAL ENVIRONMENT AND CHEMICAL FACTORS ON LUMINESCENCE PROPERTIES OF EUROPIUM (Ⅱ) ION
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作者 孙家跃 石春山 李有谟 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期110-116,共7页
In this paper,the influence of crystal-field on the Luminescence properties of Eu^(2+) in complex oxides are studied theoretically by using purely electrostatic model,the dependence of the 4f^65d levels on Eu-O bond d... In this paper,the influence of crystal-field on the Luminescence properties of Eu^(2+) in complex oxides are studied theoretically by using purely electrostatic model,the dependence of the 4f^65d levels on Eu-O bond distance is given.Quantum chemistry calculation shows that the splitting extent of 4f^65d energy band in cubic or in octahedral fields will be inversely proportional to R^5,where R is the distance of Eu^(2+) to oxygen ligand.The value of R affects slightly the location of the centre of 4f^65d energy band.According to the exper- imental spectrum data,we have discussed the influence of the host chemical composition,the replaced sites of Eu^(2+) and degree of covalency of Eu-O bond on luminescence properties of Eu^(2+).Some regularity of fluorescence spectrum was observed. In alkali-alkaline earth-phosphates,the splitting extent of 4f^65d band (△E) becomes smaller as the Eu-O bond distance (R) increases.In Na_(3-x)(PO_4)_(1-x)(SO_4)_x and Na_(2-x)CaSi_(1-x)P_xO_4 hosts,d-d emission peak of Eu^(2+) will shift to shorter wavelength with the increase of x's value. The crystal structure data show that Eu^(2+) in K_2Mg_2(SO_4)_3 is affected more strongly by crystal-field and covalancy than in KMgF_3,so K_2Mg_2(SO_4)_3:Eu^(2+) emits blue light (E_(em)~m=400nm) and KMgF_3:Eu^(2+) produces ultraviolet fluorescence. 展开更多
关键词 Eu SPECTRAL VARIATION AND CHARACTERISTICS OF LOW VALENCY RARE EARTH IONS IN complex oxides EFFECT OF THE CRYSTAL ENVIRONMENT AND CHEMICAL FACTORS ON LUMINESCENCE PROPERTIES OF EUROPIUM ION
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Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex 被引量:3
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作者 高洪成 颜岩 +5 位作者 徐晓弘 于杰辉 牛会玲 高文秀 张文祥 贾明君 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1811-1817,共7页
The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.... The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates. 展开更多
关键词 Supramolecular compound Molybdenum oxide cluster Copper complex Olefin Epoxidation
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Novel cobalt(Ⅱ) complexes of amino acids-Schiff bases catalyzed aerobic oxidation of various alcohols to ketones and aldehyde 被引量:13
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作者 Seyed Mohammad Seyedi Reza Sandaroos Gholam Hossein Zohuri 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第11期1303-1306,共4页
Two cobalt(Ⅱ) complexes 1 and 2 of Schiff bases derived from amino acids were synthesized and used for oxidation of benzyl alcohol with molecular oxygen at different conditions of pH,solvent,temperature and complex... Two cobalt(Ⅱ) complexes 1 and 2 of Schiff bases derived from amino acids were synthesized and used for oxidation of benzyl alcohol with molecular oxygen at different conditions of pH,solvent,temperature and complex/alcohol molar ratio to optimize reaction conditions and to evaluate the catalytic efficiency of new cobalt Schiff base complexes.Under obtained optimum conditions,various alcohols were oxidized to corresponding aldehydes and ketones. 展开更多
关键词 Cobalt(Ⅱ) complexes Alcohol oxidation Aerobic oxidation
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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance 被引量:13
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作者 YUAN Wei-ling CAO Cou-gui LI Cheng-fang ZHAN Ming CAI Ming-li WANG Jin-ping 《Agricultural Sciences in China》 CAS CSCD 2009年第10期1246-1255,共10页
Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and thei... Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials (GWPs), we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly (P〈 0.05) lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly (P〈0.05) higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK (5 997.6 and 5 391.5 RMB yuan ha^-1). Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits. 展开更多
关键词 methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem greenhouse effect economic benefit
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Synthesis of a new ordered mesoporous NiMoO_4 complex oxide and its efficient catalytic performance for oxidative dehydrogenation of propane 被引量:7
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作者 Xiaoqiang Fan Jianmei Li +4 位作者 Zhen Zhao Yuechang Wei Jian Liu Aijun Duan Guiyuan Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期171-178,共8页
Highly ordered mesoporous NiMoO4 material was successfully synthesized using mesoporous silica KIT-6 as hard template via vacuum nanocasting method. The structure was characterized by means of XRD, TEM, N2 adsorption-... Highly ordered mesoporous NiMoO4 material was successfully synthesized using mesoporous silica KIT-6 as hard template via vacuum nanocasting method. The structure was characterized by means of XRD, TEM, N2 adsorption-desorption, Raman and FT-IR. The mesoporous NiMoO4 with the coexistence of a-NiMoO4 and fl-NiMoO4 showed well-ordered mesoporous structure, a bimodal pore size distribution and crystalline framework. The catalytic performance of NiMoOa was investigated for oxidative dehydrogenation of propane. It is demonstrated that the mesoporous NiMoO4 catalyst with more surface active oxygen species showed better catalytic performance in oxidative dehydrogena- tion of propane in comparison with bulk NiMoO4. 展开更多
关键词 ----w 7ordered mesoporous structure NiMoO4 complex oxide vacuum nanocasting PROPANE oxidative dehydrogenation
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Catalytic combustion of diesel soot over K_2NiF_4-type oxides La_(2-x)K_xCuO_4 被引量:6
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作者 朱玲 王学中 梁存珍 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期254-257,共4页
Nanostructure K2NiF4 type oxides La2-xKxCuO4 complex oxides were prepared using the Sol-Gel method, characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared (FT-IR), and Scanning Electron Microscopy (... Nanostructure K2NiF4 type oxides La2-xKxCuO4 complex oxides were prepared using the Sol-Gel method, characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared (FT-IR), and Scanning Electron Microscopy (SEM). The catalytic activity for soot combustion was evaluated by the Temperature-Programmed Reaction (TPO) technique. The results demonstrated that the substitution quality of K^+ for La^3+ at the A-site would increase the catalytic activities of La2-xKxCuO4 for soot combustion greatly; the substitution quality affected the structure and catalytic activity obviously. The La1.8K0.2CuO4 complex oxides with tetrahedral structures had the best catalytic activity for soot combustion, and the ignition temperature of soot combustion was lowered from 490 to 320 ℃. 展开更多
关键词 K2NiF4-type complex oxides SOOT catalytic combustion rare earths
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Dioxygen Affinity and Catalytic Performance of Bis-(furaldehyde) Schiff Bases Co(II) Complexes in Cyclohexene Oxidation 被引量:4
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作者 Sun, B Chen, JR +1 位作者 Hu, JY Li, XJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期1043-1046,共4页
Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of th... Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed. 展开更多
关键词 Schiff base cobalt (II) complex OXYGENATION catalytic oxidation CYCLOHEXENE
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Baeyer-Villiger oxidation of ketones with hydrogen peroxide catalyzed by Sn-aniline complex 被引量:2
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作者 Qing Hua Zhang Shou Feng Wang Zi Qiang Lei 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第1期4-6,共3页
Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline com... Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline complex. 展开更多
关键词 Baeyer-Villiger oxidation Sn-aniline complex Ketone oxidation Hydrogen peroxide
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RANDOM COPOLYMER OF PROPYLENE OXIDE AND ETHYLENE OXIDE PREPARED BY DOUBLE METAL CYANIDE COMPLEX CATALYST 被引量:2
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作者 Yi-jun Huang Guo-rong Qi +1 位作者 Guan-xi Chen Department of Polymer Science and Engineering, Zhejiang University Hangzhou 310027,China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第5期453-459,共7页
Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H... Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition. 展开更多
关键词 propylene oxide ethylene oxide double metal cyanide complex
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