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Invariance and Noises of Shannon Entropy for Information on Oxidative Activity of DNA in All Living Cells for Medical Diagnostics
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作者 Nikolay E. Galich 《American Journal of Operations Research》 2014年第2期72-89,共18页
We analyze oxidative activity of DNA due to fluorescence of chromosomes inside cells, using flow cytometry method with nanometer spatial resolution. Statistics of fluorescence is presented in histogram as frequency di... We analyze oxidative activity of DNA due to fluorescence of chromosomes inside cells, using flow cytometry method with nanometer spatial resolution. Statistics of fluorescence is presented in histogram as frequency distributions of flashes in the dependence on their intensity and in distributions of Shannon entropy, which was defined on the base of normalized distribution of information in original histogram for frequency of flashes. We show that overall sum of entropy, i.e. total entropy E , for any histogram is invariant and has identical trends of changes all values of E(r) = lnr at reduction of histogram’ rank r. This invariance reflects informational homeostasis of chromosomes activity in multi-scale networks of entropy inside all cells in various samples of blood for DNA inside neutrophils, lymphocytes, inside all leukocytes of human and inside chicken erythrocytes for various dyes, colors and various excitations of fluorescence. Informational homeostasis of oxidative activity of 3D DNA in the full set of chromosomes inside living cells exists for any Shannon-Weaver index of biodiversity of cells, at any state of health different beings. Regulation perturbations in information activity DNA provides informational adaptability and vitality of cells at homeostasis support. Noises of entropy, during regulation of informational homeostasis, depend on the states of health in real time. The main structural reconstructions of chromosomal correlations, corresponding to self-regulation of homeostasis, occur in the most large-scale networks of entropy, for rank r<32. We show that stability of homeostasis is supported by activity of all 46 chromosomes inside cells. Patterns, hidden switching and branching in sequences of averages of H?lder and central moments for noises in regulation of homeostasis define new opportunities in diagnostics of health and immunity. All people and all aerobic beings have one overall homeostatic level for countdown of information activity of DNA inside cells. We noted very bad and dangerous properties of artificial cells with other levels of informational homeostasis for all aerobic beings in foods, medical treatment and in biotechnologies. 展开更多
关键词 Averages of Holder for Noises of Shannon Entropy in Homeostasis Regulation of Total Shannon Entropy Entropy and Information of DNA activity in Cells Information Entropy for oxidizing activity of DNA Informational Homeostasis and Self-Regulation of DNA activity in Cells Noise of Information Entropy
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Electron Donating Property and Catalytic Activity ofPerovskite-type Mixed Oxides (ABO_3) Consisting of Rare Earth and 3d Transition Metals
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作者 S.Sugunant and V.Meera(Dept. of Applied Chemistry, Cochin University of Science and Technology, Kochi-682022, India) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第3期229-231,共3页
The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have... The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have been correlated with the surface electron donor properties of these mixed oxides 展开更多
关键词 activity type ABO3 Consisting of Rare Earth and 3d Transition Metals Electron Donating Property and Catalytic activity ofPerovskite-type Mixed Oxides
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Enhanced cycle performance of Li/S battery with the reduced graphene oxide/activated carbon functional interlayer 被引量:8
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作者 Haipeng Li Liancheng Sun +3 位作者 Yongguang Zhang Taizhe Tan Gongkai Wang Zhumabay Bakenov 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1276-1281,共6页
The high-energy lithium/sulfur(Li/S) battery has become a very popular topic of research in recent years due to its high theoretical capacity of 1672 m Ah/g. However, the polysulfide shuttle effect remains of great co... The high-energy lithium/sulfur(Li/S) battery has become a very popular topic of research in recent years due to its high theoretical capacity of 1672 m Ah/g. However, the polysulfide shuttle effect remains of great concern with a great number of publications dedicated to its mitigation. In this contribution, a three-dimensional(3D) reduced graphene oxide/activated carbon(RGO/AC) film, synthesized by a simple hydrothermal method and convenient mechanical pressing, is sandwiched between the separator and the sulfur-based cathode, acting as a functional interlayer to capture and trap polysulfide species. Consequently, the Li/S cell with this interlayer shows an impressive initial discharge capacity of 1078 m Ah/g and a reversible capacity of 655 m Ah/g even after 100 cycles. The RGO/AC interlayer impedes the movement of polysulfide while providing unimpeded channels for lithium ion mass transfer. Therefore, the RGO/AC interlayer with a well-designed structure represents strong potential for high-performance Li/S batteries. 展开更多
关键词 Lithium/sulfur battery Shuttle effect Functional interlayer Reduced graphene oxide/activated carbon composite
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Immobilized reactor for rapid destruction of recalcitrant organics and inorganics in tannery wastewater 被引量:4
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作者 A.Ganesh Kumar G.Sekaran +1 位作者 S.Swarnalatha B.Prasad Rao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第4期681-685,共5页
The wastewater discharged from tanneries lack biodegradability due to the presence of recalcitrant compounds at significant concentration. The focal theme of the present investigation was to use chemo-autotrophic acti... The wastewater discharged from tanneries lack biodegradability due to the presence of recalcitrant compounds at significant concentration. The focal theme of the present investigation was to use chemo-autotrophic activated carbon oxidation(CAACO) reactor, an immobilized cell reactor using chemoautotrophs for the treatment of tannery wastewater. The treatment scheme comprised of anaerobic treatment, sand filtration, and CAACO reactor, which remove COD, BOD, TOC, VFA and sulphides respectively by 86%, 95%, 81%, 71% and 100%. Rice bran mesoporous activated carbon prepared indigenously and was used for immobilization of chemoautotrophs. The degradation of xenobiotic compounds by CAACO was confirmed through HPLC and FT-IR techniques. 展开更多
关键词 chemo-autotrophic activated carbon oxidation(CAACO) mesoporous rice bran activated carbon XENOBIOTIC
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Effects of selenium and sulfur on antioxidants and physiological parameters of garlic plants during senescence 被引量:3
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作者 CHENG Bo LIAN Hai-feng +5 位作者 LIU Ying-ying YU Xin-hui SUN Ya-li SUN Xiu-dong SHI Qing-hua LIU Shi-qi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期566-572,共7页
A hydroponic study was conducted to determine the effects of selenium(Se: 0, 3, 6 μmol L^-1) on senescence-related oxidative stress in garlic plants grown under two sulfur(S) levels. We evaluated the yields of p... A hydroponic study was conducted to determine the effects of selenium(Se: 0, 3, 6 μmol L^-1) on senescence-related oxidative stress in garlic plants grown under two sulfur(S) levels. We evaluated the yields of plants harvested at 160 and 200 days after sowing. Plants grown under a low Se dose(0.3 μmol L^-1) at low S level showed higher yields(12.0% increase in fresh weight yield, 13.7% increase in dry weight yield) than the controls, despite a decrease in chlorophyll concentration. Compared with control plants, the Se-treated plants showed lower levels of lipid peroxidation. The Se-treated plants also showed higher activities of glut athione peroxidase and catalase, but lower superoxide dismutase activities. Changes in Fv/Fm values and proline contents were affected more strongly by S than by Se. On the basis of our results, we can conclude that Se plays a key role in the antioxidant systems in garlic seedlings. It delays senescence by alleviating the peroxide stress, but it can be toxic at high levels. A high S level may increase tolerance to high Se concentrations through reducing Se accumulation in plants. 展开更多
关键词 selenium sulfur garlic antioxidant activity oxidative stress senescence
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Reduction of chromium oxides in stainless steel dust 被引量:1
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作者 Yan-ling Zhang Wen-ming Guo Xin-lei Jia 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第6期573-581,共9页
The recovery of metal oxides from stainless steel dust using C(graphite), SiFe, and Al as reductants was investigated under various conditions. The apparent distribution ratio of Cr(L Cr ′^m/s ) in the recovered ... The recovery of metal oxides from stainless steel dust using C(graphite), SiFe, and Al as reductants was investigated under various conditions. The apparent distribution ratio of Cr(L Cr ′^m/s ) in the recovered metal and residual slag phases was defined as the major performance metric. The results show that the recovery ratio of metals increases as the ratio of CaO :SiO2 by mass in the residual slag increases to 1.17. The residual content of metals in the slag decreases as the Al2O3 content of the slag is increased from approximately 8wt% to 10wt%. The recovery ratio of Cr increases with increasing L Cr ′^ m/s , and a linear relationship between L Cr ′^m/s and the activity coefficient ratio of CrO in the slag and the recovered metal phase is observed. The combination of C and SiFe or Al as the reducing agents reveals that Si is the more effective coreductant. 展开更多
关键词 stainless steel dust chromium oxides recovery apparent distribution ratio activity coefficient
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Effect of CeO_2 on Crystal Structures and Catalytic Properties of the Mn_2O_3 Catalysts
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作者 罗孟飞 朱波 袁贤鑫 《Journal of Rare Earths》 SCIE EI CAS CSCD 1994年第4期259-263,共5页
The manganese-cerium complex oxide catalysts were prepared by coprecipitation.The crystal structures,the desorption properties of surface oxygen and reducibility of these catalysts were investigated by means of X-ray ... The manganese-cerium complex oxide catalysts were prepared by coprecipitation.The crystal structures,the desorption properties of surface oxygen and reducibility of these catalysts were investigated by means of X-ray diffraction analysis (XRD),temperature-programmed desopotion-mass spectrography (TPD-MS) and temperature-programmed reduction (TPR).The crystal structure of Mn-O and Mn-Ce-O catalysts are bixbyite-Mn2O3 and γ-Mn2O3 respectively.The presence of CeO2 can not change the position of the feature peaks of Mn2O3 on the TPD or profiles,but can increase evidently the amount of the adsorbed surface oxygen,which are correlated with the catalytic activity for methanol oxidation.The activity of the catalyst is optimum when Mn/Ce atom ratio is 4:1.The presence of CeO2 brings a change of the reducibility,which reveals that there is an interaction between Mn2O3 and CeO2. 展开更多
关键词 Mn_2O_3 CeO_2 Surface oxygen Oxidation activity Crystal structure
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Effect of Addition of Sm_2O_3 on Property of CuO-γ-Al_2O_3 Catalyst
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作者 蒋晓原 周仁贤 +1 位作者 毛建新 郑小明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第3期20-26,共7页
Effect of the addition of Sm 2O 3 on CuO γ Al 2O 3 catalyst for CO oxidation reaction was investigated. The result shows that the right amount of Sm 2O 3 can promote the adsorption of the surface oxygen a... Effect of the addition of Sm 2O 3 on CuO γ Al 2O 3 catalyst for CO oxidation reaction was investigated. The result shows that the right amount of Sm 2O 3 can promote the adsorption of the surface oxygen and recovery of CuO γ Al 2O 3 catalyst. Sm 2O 3 plays an important role in change of γ Al 2O 3 phase into θ Al 2O 3 phase. In addition, the right amount of Sm 2O 3(5%) can improve the oxidation activity of the CuO γ Al 2O 3 catalyst. Whereas an excess of Sm 2O 3(10%) makes the CuO crystal in CuO γ Al 2O 3 catalyst become bigger and restrain the oxidation activity of the CuO γ Al 2O 3 catalyst. 展开更多
关键词 Rare earths CuO γ Al 2O 3 catalyst Sm 2O 3 Oxidation activity
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Intensification of bituminous coal and lignite oxidation by copper-based activating additives
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作者 K.B.Larionov I.V.Mishakov +1 位作者 K.V.Slyusarskiy A.A.Vedyagin 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第1期141-153,共13页
The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by the... The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region. 展开更多
关键词 Coal Activated oxidation Copper nitrate Copper sulfate Copper acetate Thermo-gravimetric and mass spectrometry analysis
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Experimental Design Technique on Removal of Hydrogen Sulfide using CaO-eggshells Dispersed onto Palm Kernel Shell Activated Carbon:Experiment,Optimization,Equilibrium and Kinetic Studies
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作者 OMAR Abed Habecb RAMESH Kanthasamy +1 位作者 GOMAA A. M. Ali ROSLI bin Mohd Yunus 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期305-320,共16页
This study presents the use of chicken eggshells waste utilizing palm kernel shell based activated carbon(PKSAC) through the modification of their surface to enhance the adsorption capacity of H2S. Response surface ... This study presents the use of chicken eggshells waste utilizing palm kernel shell based activated carbon(PKSAC) through the modification of their surface to enhance the adsorption capacity of H2S. Response surface methodology technique was used to optimize the process conditions and they were found to be: 500 mg/L for H2S initial concentration, 540 min for contact time and 1 g for adsorbent mass. The impacts of three arrangement factors(calcination temperature of impregnated activated carbon(IAC), the calcium solution concentration and contact time of calcination) on the H2S removal efficiency and impregnated AC yield were investigated. Both responses IAC yield(IACY, %) and removal efficiency(RE, %) were maximized to optimize the IAC preparation conditions. The optimum preparation conditions for IACY and RE were found as follows: calcination temperature of IAC of 880 ℃, calcium solution concentration of 49.3% and calcination contact time of 57.6 min, which resulted in 35.8% of IACY and 98.2% RE. In addition, the equilibrium and kinetics of the process were investigated. The adsorbent was characterized using TGA, XRD, FTIR, SEM/EDX, and BET. The maximum monolayer adsorption capacity was found to be 543.47 mg/g. The results recommended that the composite of PKSAC and Ca O could be a useful material for H2S containing wastewater treatment. 展开更多
关键词 water treatment hydrogen sulfide response surface methodology optimization activated carbon adsorption isotherm kinetics calcium oxide
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Regeneration of Spent Catalyst and Impregnation of Catalyst by Supercritical Fluid
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作者 Farid M. Gumerov Bernard Le Neindre +1 位作者 Timur R. Bilalov Ajrat A. Sagdeev 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第4期51-65,共16页
The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The an... The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book. 展开更多
关键词 Palladium Catalyst G-58E Nickel/Kieselguhr/Diatomite Catalyst Active Aluminum Oxide Catalyst Palladium Catalyst LD-265 Nickel-Molybdenum Catalysts DN-3531 and Criterion 514 Catalyst Regeneration Catalyst activity Benzonitrile Complex of Palladium Chloride Styrene Complex of Palladium Chloride Cyclohexene Complex of Palladium Chloride
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Facile synthesis and excellent catalytic activity of gold nanoparticles on graphene oxide 被引量:4
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作者 Yong Qiang He Na Na Zhang +4 位作者 Yu Liu Jian Ping Gao Mao Cong Yi Qiao Juan Gong Hai Xia Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期41-44,共4页
For the first time,Au nanoparticles on graphene oxide(GO-AuNPs) were successfully fabricated without applying any additional reductants,just by the redox reaction between AuCl_4^(-1) and GO.Their structure was cha... For the first time,Au nanoparticles on graphene oxide(GO-AuNPs) were successfully fabricated without applying any additional reductants,just by the redox reaction between AuCl_4^(-1) and GO.Their structure was characterized by transmission electron microscopy and X-ray powder diffraction.The results show that flower-like AuNPs were successfully dispersed on GO surface.Importantly,they showed a high catalytic activity for the Suzuki-Miyaura coupling reaction in an aqueous medium. 展开更多
关键词 Graphene oxide Au nanoparticles Catalytic activity Suzuki-Miyaura coupling reaction
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Synthesis of α-Mo_2C by Carburization of α-MoO_3 Nanowires and Its Electrocatalytic Activity towards Tri-iodide Reduction for Dye-Sensitized Solar Cells 被引量:3
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作者 J.Theerthagiri R.A.Senthil +2 位作者 M.H.Buraidah J.Madhavan A.K.Arof 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第12期1339-1344,共6页
Nanowire-shaped α-Mo O3 was synthesized on a large scale by hydrothermal route.Nanocrystalline α-Mo2 C phase was obtained by the carburization of α-Mo O3 nanowires with urea as a carbon source precursor.The phase p... Nanowire-shaped α-Mo O3 was synthesized on a large scale by hydrothermal route.Nanocrystalline α-Mo2 C phase was obtained by the carburization of α-Mo O3 nanowires with urea as a carbon source precursor.The phase purity and crystalline size of the synthesized materials were ascertained by using powder X-ray diffraction.The shape and morphology of synthesized materials were characterized by field-emission scanning electron microscopy(FE-SEM) and high resolution transmission electron microscopy(HR-TEM).The electrocatalytic activity of α-Mo2 C for I-/I3^-redox couple was investigated by the cyclic voltammetry.The synthesized α-Mo2 C was subsequently applied as counter electrode in dye-sensitized solar cells to replace the expensive platinum. 展开更多
关键词 Counter electrode Dye-sensitized solar cells Electrocatalytic activity Molybdenum carbide Molybdenum oxide
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Activity Calculation by Application of Sub-Regular Solution Model in Binary Oxide Systems 被引量:1
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作者 HOU Yan-qing XIE Gang +2 位作者 TAO Dong-ping LI Rong-xing YU Xiao-hua 《Journal of Iron and Steel Research(International)》 SCIE CAS CSCD 2012年第7期33-38,共6页
To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been s... To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2 % and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16 % and 1088 % in the systems presenting saturation concentration. The results show that sub-regular solu- tion model is not good for predicting the systems presenting saturation concentration, especially for the systems con- taining acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example (SiO4)4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub- regular solution model is closer to the characteristics of actual solution and the calculated results are superior. 展开更多
关键词 sub-regular solution models binary oxide system activity
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Theoretical Study on the Antioxidant Activity of Curcumin
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作者 孙友敏 王若曦 +2 位作者 苑世领 林宪杰 刘成卜 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第8期827-830,共4页
The computational results for curcumin at the B3LYP/6-31G(d,p) level show that the enol form of curcumin is more stable than the diketo form because of an intramolecular hydrogen bond, which extends the conjugation e... The computational results for curcumin at the B3LYP/6-31G(d,p) level show that the enol form of curcumin is more stable than the diketo form because of an intramolecular hydrogen bond, which extends the conjugation effect in the enol chain, formed in the enol structure. Cis-diketone form can not be obtained, presumably due to the strong repulsion between the carbonyl dipoles aligned in parallel. According to the phenolic O—H bond dissociation en- thalpy, curcumin in its most stable form can be suggested to be a relatively good antioxidant. In order to avoid overcoming H-bond interaction and to improve the antioxidant activity of curcumin, a catechol moiety was incor- porated into curcumin for designing a novel antioxidant. It is found that the designed molecule is much more effi- cient to scavenge radical than curcumin, comparable to vitamin E. Moreover, the ionization potential of the de- signed molecule is similar to that of curcumin, indicating that the designed molecule can not display the prooxidant effect. 展开更多
关键词 CURCUMIN density functional theory O—H bond dissociation enthalpy ionization potential anti- oxidant activity
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Cerium(Ⅳ)ammonium nitrate(CAN)-mediated regioselective synthesis and anticancer activity of 6-substituted 5,8-dimethoxy-1,4-naphthoquinone
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作者 Guang Huang Hui-Ran Zhao +5 位作者 Qing-Qing Meng Wen Zhou Qi-Jing Zhang Jin-Yun Dong Jia-Hua Cui Shao-Shun Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第7期1553-1558,共6页
6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones(6-DMNQ),the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H... 6-Substituted 5,8-O-dimethyl-1,4-naphthoquinones(6-DMNQ),the promising anticancer scaffolds,were selectively generated by oxidative demethylation of 2-substituted 1,4,5,8-tetramethoxynaphthalenes with CAN in EtOAc/H2O in comparatively high yields.An interesting finding was that apart from the reported electron-withdrawing effects of substituents on position 2 of naphthalene ring,regioselective synthesis of 6-DMNQ was largely dependent on the steric effects in CAN-mediated oxidation.The selective cytotoxicities of 6-DMNQ from the in vitro cell-based assays were exhibited between the cancer cells and normal cells.Moreover,most of sulfur-containing 6-DMNQ derivatives displayed better anticancer activities than the corresponding oxygen-containing ones,which could provide an available strategy for the design of 6-DMNQ derivatives as potential anticancer agents. 展开更多
关键词 6-Substituted 5 8-O-dimethyl-1 4- naphthoquinone Cerium(Ⅳ) ammonium nitrate Regioselective oxidation Steric effects Antitumor activity Sulfur-containing
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Shape design of cerium oxide nanoparticles for enhancement of enzyme mimetic activity in therapeutic applications
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作者 Tamaki Naganuma 《Nano Research》 SCIE EI CAS CSCD 2017年第1期199-217,共19页
Cerium oxide nanoparticles (CONPs), widely used in catalytic applications owing to their robust redox reaction, are now being considered in therapeutic applications based on their enzyme mimetic properties such as c... Cerium oxide nanoparticles (CONPs), widely used in catalytic applications owing to their robust redox reaction, are now being considered in therapeutic applications based on their enzyme mimetic properties such as catalase and super oxide dismutase (SOD) mimetic activities. In therapeutic applications, the emerging demand for CONPs with low cytotoxicity, high cost efficiency, and high enzyme mimetic capability necessitates the exploration of alternative synthesis and effective material design. This study presents a room temperature aqueous synthesis for low-cost production of shape-selective CONPs without potentially harmful organic substances, and additionally, investigates cell viability and catalase and SOD mimetic activities. This synthesis, at room temperature, produced CONPs with particular planes: {111}/{100} nanopolyhedra, {100} nano/submicron cubes, and {111}/{100} nanorods that grew in [110] longitudinal direction. Enzymatic activity assays indicated that nanopolyhedra with a high concentration of Ce4+ ions promoted catalase mimetic activity, while nanocubes and nanorods with high Ce3+ ion concentrations enhanced SOD mimetic activity. This is the first study indicating that shape and facet configuration design of CONPs, coupled with the retention of dominant, specific Ce valence states, potentiates enzyme mimetic activities. These findings may be utilized for CONP design aimed at enhancing enzyme mimetic activities in therapeutic applications. 展开更多
关键词 super oxide dismutase(SOD) and catalasemimetic activity shape and facetconfiguration Ce valence states room temperature aqueoussynthesis
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Further study on the synthesis of F-containing porphyrins and their catalytic activity on oxidation of cyclohexene
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作者 HUANG,Wei-Yuan YING,Wei-Wen MA,Wu-Ping Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1993年第5期464-471,共8页
Reaction of tetrakis(p-allyloxyphenyl)porphyrin and perfluoroalkanesulfonyl bromides gives tetrakis(p-polyfluoroalkoxylphenyl)substituted porphyrins.The yields are over 90%.The synthesis of the metal ion complexes of ... Reaction of tetrakis(p-allyloxyphenyl)porphyrin and perfluoroalkanesulfonyl bromides gives tetrakis(p-polyfluoroalkoxylphenyl)substituted porphyrins.The yields are over 90%.The synthesis of the metal ion complexes of these F-containing porphyrins is also reported.Preliminary results on the study of the catalytic activity of the manganese(Ⅲ)complexes of various fluorinated porphyrins on oxidation of cyclohexene indicate that the introduction of R_F group into porphyrin contributes to the stability of the catalysts. 展开更多
关键词 meta Further study on the synthesis of F-containing porphyrins and their catalytic activity on oxidation of cyclohexene
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Selective and effective oxidation of 5-hydroxymethylfurfural by tuning the intermediates adsorption on Co-Cu-CN_(x) 被引量:1
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作者 Tianyun Jing Shaokang Yang +3 位作者 Yonghai Feng Tingting Li Yunpeng Zuo Dewei Rao 《Nano Research》 SCIE EI CSCD 2023年第5期6670-6678,共9页
Co-based catalysts are promising alternatives to precious metals for the selective and effective oxidation of 5-hydroxymethylfurfural(HMF)to the higher value-added 2,5-furandicarboxylic acid(FDCA).However,these cataly... Co-based catalysts are promising alternatives to precious metals for the selective and effective oxidation of 5-hydroxymethylfurfural(HMF)to the higher value-added 2,5-furandicarboxylic acid(FDCA).However,these catalysts still suffer from unsatisfactory activity and poor selectivity.A series of N-doped carbon-supported Co-based dual-metal nanoparticles(NPs)have been designed,among which the Co-Cu_(1.4)-CN_(x) exhibits enhanced HMF oxidative activity,achieving FDCA formation rates 4 times higher than that of pristine Co-CN_(x),with 100%FDCA selectivity.Density functional theory(DFT)calculations evidenced that the increased electron density on Co sites induced by Cu can mediate the positive electronegativity offset to downshift the dband center of Co-Cu_(1.4)-CN_(x),thus reducing the energy barriers for the conversion of HMF to FDCA.Such findings will support the development of superior non-precious metal catalysts for HMF oxidation. 展开更多
关键词 Co-based materials 5-hydroxymethylfurfural(HMF)oxidative activity 2 5-furandicarboxylic acid(FDCA)selectivity electronegativity offset d-band center
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MIL-101(Cr)-decorated Ti/TiO_(2) anode for electrochemical oxidation of aromatic pollutants from water 被引量:1
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作者 Zepeng Zhang Yunyun Li +4 位作者 Longzhang Dong Zhonglong Yin Ziqi Tian Weiben Yang Zhen Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期301-305,共5页
Hydroxyl radicals(·OH) generated on anode play a vital role in electrochemical oxidation(EO) of organic pollutants for water treatment. Inspired by the four-electron oxygen evolution reaction(OER), we supposed an... Hydroxyl radicals(·OH) generated on anode play a vital role in electrochemical oxidation(EO) of organic pollutants for water treatment. Inspired by the four-electron oxygen evolution reaction(OER), we supposed an anode-selection strategy to stabilize deeply oxidized states(*O and*OOH) which are beneficial to generating·OH. To verify the hypothesis, a candidate anode component(MIL-101(Cr), a well-known metal-organic framework with active variable-valence transition metal centers) was used to coat Ti/TiO_(2)plate to fabricate anodes. Compared to TiO_(2)(101) plane on undecorated anode surface, fast and complete removal of aniline and phenol, and improved energy utilization were achieved on MIL-101(Cr)-coatedTi/TiO_(2)anode. Mechanism investigation, including pollutant degradation pathways, showed the predominate contribution(69.60%–75.13%) of·OH in pollutant mineralization. Density functional theory(DFT)computations indicated Cr site in MIL-101(Cr) was more conducive to stabilizing*O and*OOH, leading to thermodynamical spontaneous generation of·OH. This work opens up an exciting avenue to explore·OH production, and supplies a useful guidance to the development of anode materials for EO process. 展开更多
关键词 Active oxidation species Electrocatalytic oxidation DFT computation MOF Hydroxyl radical Composite anode
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