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New environmental-friendly yellow pigments Y4-xAxMoO9+δ(A =Ta,Tb)
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作者 Mengjun Cai Shuaifeng Chen +1 位作者 Xinsheng Ma Jianding Chen 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第7期741-749,共9页
A series of inorganic yellow pigments with general formula Y4-xAxMoO9+δ(A = Ta, Tb), where x = 0,0.05,0.1,0.2, 0.4 for Ta and χ = 0, 0.005, 0.01.0.03, 0.05 for Tb,were synthesized by a conventional ceramic method at... A series of inorganic yellow pigments with general formula Y4-xAxMoO9+δ(A = Ta, Tb), where x = 0,0.05,0.1,0.2, 0.4 for Ta and χ = 0, 0.005, 0.01.0.03, 0.05 for Tb,were synthesized by a conventional ceramic method at 1400 ℃ for 6 h in air. The samples were characterized by XRD,EDS,XPS,SEM,TG-DSC,UV-vis-NIR reflectance spectroscopy and CIE L*a*b* color scales. It is found that the substitution of A(A = Ta, Tb) for Y3+ in Y4 MoO9 decreases the NIR reflectance of the pigment samples, but the developed pigments Y4-xAxMoO9+δ(A = Ta, Tb) still exhibit impressive NIR solar reflectance. The brighter yellow color of inorganic pigments Y4-xAxMoO9+δ(A = Ta, Tb) is available when x is about 0.1 for Ta and 0.01 for Tb. The results make them a series of potential candidates as ecological yellow pigments because of their high reflectance, lightness, intense coloration and excellent thermal and chemical stability. 展开更多
关键词 YTTRIUM OXIDE Molybdenum OXIDE TANTALUM OXIDE TERBIUM OXIDE INORGANIC yellow PIGMENT Rare earths
Synthesis, properties, and applications of graphene oxide/reduced graphene oxide and their nanocomposites 预览
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作者 Andrew T. Smith Anna Marie LaChance +2 位作者 Songshan Zeng Bin Liu Luyi Sun 《纳米材料科学(英文版)》 CAS 2019年第1期31-47,共17页
Thanks to their remarkable mechanical, electrical, thermal, and barrier properties, graphene-based nanocomposites have been a hot area of research in the past decade. Because of their simple top-down synthesis, graphe... Thanks to their remarkable mechanical, electrical, thermal, and barrier properties, graphene-based nanocomposites have been a hot area of research in the past decade. Because of their simple top-down synthesis, graphene oxide (GO) and reduced graphene oxide (rGO) have opened new possibilities for gas barrier, membrane separation, and stimuli-response characteristics in nanocomposites. Herein, we review the synthesis techniques most commonly used to produce these graphene derivatives, discuss how synthesis affects their key material properties, and highlight some examples of nanocomposites with unique and impressive properties. We specifically highlight their performances in separation applications, stimuli-responsive materials, anti-corrosion coatings, and energy storage. Finally, we discuss the outlook and remaining challenges in the field of practical industrial-scale production and use of graphene-derivative-based polymer nanocomposites. 展开更多
关键词 GRAPHENE OXIDE Reduced GRAPHENE OXIDE GRAPHENE quantum DOTS polymer NANOCOMPOSITES SYNTHESIS PROPERTIES of GRAPHENE and GRAPHENE OXIDE Applications
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Electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O system for Dy–Cu intermediate alloy production 预览
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作者 Shu-mei Chen Chun-fa Liao +3 位作者 Jue-yuan Lin Bo-qing Cai Xu Wang Yun-fen Jiao 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第6期701-709,共9页
Dy–Cu intermediate alloys have shown substantial potential in the field of magnetostrictive and magnetic refrigerant materials.Therefore,this study focused on investigating the electrical conductivity of molten-salt ... Dy–Cu intermediate alloys have shown substantial potential in the field of magnetostrictive and magnetic refrigerant materials.Therefore,this study focused on investigating the electrical conductivity of molten-salt systems for the preparation of Dy–Cu alloys and on optimizing the corresponding operating parameters.The electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O systems was measured from 910 to 1030°C using the continuously varying cell constant method.The dependencies of the LiF–DyF3–Dy2O3–Cu2O system conductivity on the melt composition and temperature were examined herein.The optimal operating conditions for Dy–Cu alloy production were determined via analyses of the electrical conductivity and activation energies for conductance,which were calculated using the Arrhenius equation.The conductivity of the molten system regularly increases with increasing temperature and decreases with increasing concentration of Dy2O3 or Cu2O or both.The activation energy Eκof the LiF–DyF3–Dy2O3 and LiF–DyF3–Cu2O molten-salt systems increases with increasing Dy2O3 or Cu2O content.The regression functions of conductance as a function of temperature(t)and the addition of Dy2O3(W(Dy2O3))and Cu2O(W(Cu2O))can be expressed asκ=-2.08435+0.0068t-0.18929W(Dy2O3)-0.07918W(Cu2O).The optimal electrolysis conditions for preparing the Dy–Cu alloy in LiF–DyF3–Dy2O3–Cu2O molten salt are determined to be 2.0wt%≤W(Dy2O3)+W(Cu2O)≤3.0wt%and W(Dy2O3):W(Cu2O)=1:2 at 970 to 1000°C. 展开更多
关键词 electrical conductivity MOLTEN salt Dy–Cu alloy DYSPROSIUM OXIDE cuprous OXIDE
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Investigation of Al2O3 and Fe2O3 transmission and transformation during the decomposition of phosphogypsum
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作者 Jie Yang Bin Zhu +1 位作者 Liping Ma Hongpan Liu 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1125-1131,共7页
Phosphogypsum(PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful.The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims ... Phosphogypsum(PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful.The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims at enriching the basic theory of coal decomposition process of PG. The emphasis was laid on the exploration of impact of main impurities on the process. On the other hand, according to Reaction Module, Equilib Module, and Phase Diagram Module of FactS age, the simulation computation was done on the systems of pure gypsum mixed with coal,with or without impurities for avoiding other impurities interference. Later, possible reactions in the process were deduced. Additionally, experiments were conducted in a TG-DTA integrated thermal gravimetric analyzer and a tube furnace. The products from the experiments were characterized and analyzed to verify the accuracy of theoretical calculations. The results showed that these impurities can change the decomposition process of PG. For example, aluminum oxide was transformed to calcium sulfoaluminate, while iron oxide was transformed to dicalcium ferrite. Furthermore, the results help to further improve the basic theory of phosphogypsum decomposition. 展开更多
关键词 PHOSPHOGYPSUM REDUCTIVE DECOMPOSITION Simulation calculations Aluminum OXIDE Iron OXIDE TERNARY DIAGRAM
Compound Oxide Catalysis CO-SCR Mechanism Research 预览
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作者 Shuting Wang Chen Yihui 《探索-环境科学与技术》 2019年第1期6-9,共4页
A series. Ce-co-oX Catalysts. prepared by co-precipitation method, CO-SCR performance.Studied. influence CO, CE ratio. activity. CO-SCR. investigated, Ce (0.3)-Co (0.7)-OXSample showed Highest NO conversion efficiency... A series. Ce-co-oX Catalysts. prepared by co-precipitation method, CO-SCR performance.Studied. influence CO, CE ratio. activity. CO-SCR. investigated, Ce (0.3)-Co (0.7)-OXSample showed Highest NO conversion efficiency 84% at 250℃. according. characterization: it. proposed, active sites.CO-SCR. Co. Ce (0.3)-Co (0.7)-OX. There. two reasons responsible. enhanced catalytic performance by Ce doping.Ce-co-oX Catalyst. firstly, specific surface area, pressureswing capacity. increased. Ce doping. Secondly a solidSolution. formed. Ce-co-oX Catalyst, resulting in the enhanced oxygen migration rate.The CO-SCR is lively to follow a mechanism that gaseous or weakly-adsorbed CO returns with adsorbed NO specialties in the forms Bridging bidendate nitrite and chelate nitrate. 展开更多
关键词 Cerium OXIDE Cobalt OXIDE CO-SCR Weak adsorbed CO BRIDGING BIDENTATE NITRITE species
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Effect of Fe2O3 on the size and components of spinel crystals in the CaO–SiO2–MgO–Al2O3–Cr2O3 system 预览
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作者 Qi-qiang Mou Jian-li Li +1 位作者 Qiang Zeng Hang-yu Zhu 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第9期1113-1119,共7页
The stability of chromium in stainless steel slag can be enhanced by increasing the spinel crystal size. The effect of Fe2O3 on the size of spinel crystals in the CaO–SiO2–MgO–Al2O3–Cr2O3 system was investigated u... The stability of chromium in stainless steel slag can be enhanced by increasing the spinel crystal size. The effect of Fe2O3 on the size of spinel crystals in the CaO–SiO2–MgO–Al2O3–Cr2O3 system was investigated using lab experiments carried out in a carbon tube fur-nace. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS) and X-ray diffraction (XRD) were used to ana-lyze the microstructure, components, and the mineral phases of synthetic slags. FactSage 7.1 was used to calculate the crystallization process of the molten slag. The results showed that the addition of Fe2O3 promoted the precipitation of spinel crystals and inhibited the formation of dicalcium silicate. The size of spinel crystals increased from 2.74 to 8.10μm and the contents of chromium and iron in the spinel varied as the Fe2O3 addition was increased from 0 to 20wt%. Fe2O3 thermodynamically provided the spinel-forming components to enhance the for-mation of FeCr2O4, MgFe2O4, and Fe3O4. The addition of Fe2O3 increased the fraction of liquid phase in a certain temperature range and promoted diffusion by decreasing the slag's viscosity. Therefore, Fe2O3 is beneficial to the growth of spinel crystals in stainless steel slag. 展开更多
关键词 ferric OXIDE STAINLESS steel SLAG SPINEL crystal SIZE chromic OXIDE
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A novel ZnO/reduced graphene oxide and Prussian blue modified carbon paste electrode for the sensitive determination of Rutin
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作者 Ozma J D'Souza Ronald J Mascarenhas +1 位作者 Ashis K Satpati Basavanakote M Basavaraja 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第2期262-270,共9页
A carbon paste modified sensor based on a novel composite of zinc oxide nanoparticles deposited on reduced graphene oxide(ZnO-rGrO) and Prussian blue(PB) was drop-cast(ZnO-rGrO-PB/MCPE) for the sensitive estimation of... A carbon paste modified sensor based on a novel composite of zinc oxide nanoparticles deposited on reduced graphene oxide(ZnO-rGrO) and Prussian blue(PB) was drop-cast(ZnO-rGrO-PB/MCPE) for the sensitive estimation of Rutin(Rtn) at pH 7.0.The high surface area of ZnO-rGrO and electrocatalytic property of PB promotes the oxidation of Rtn. Field emission scanning electron microscope(FE-SEM) and energy-dispersive X-ray spectroscopy(EDX) techniques were employed to confirm the deposition of ZnO-rGrO and PB on carbon paste electrode(CPE). The ability of ZnO-rGrO-PB/MCPE in charge transfer at the interface was investigated using electrochemical impedance spectroscopy(EIS). The heterogeneous rate constant(ks) and the charge transfer coefficient(α) have been calculated as 6.08 s-1 and 0.74 respectively. This sensor showed a wide linear response for Rtn from 7.0×10^-8to 7.0×10^-6 M and 7.0×10^-6 to 1.0×10^-4 M with a limit of detection(2.05±0.04)×10^-8 M(S/N=3). The application of ZnO-rGrO-PB/MCPE was found in the analysis of Rtn in fruit juice samples using standard addition method. This sensor showed good reproducibility, stability, selectivity and sensitivity. 展开更多
关键词 RUTIN zinc OXIDE nanoparticles REDUCED graphene OXIDE Prussian BLUE modified carbon PASTE ELECTRODE ascorbic acid
Sevoflurane postconditioning protects against myocardial ischemia/reperfusion injury by restoring autophagic flux via an NO-dependent mechanism
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作者 Shi-gang Qiao Ying Sun +6 位作者 Bo Sun An Wang Jia Qiu Lei Hong Jian-zhong An Chen Wang Hui-ling Zhang 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第1期35-45,共11页
Volatile anesthetics improve postischemic cardiac function and reduce infarction even when administered for only a brief-time at the onset of reperfusion.A recent study showed that sevoflurane postconditioning (SPC)at... Volatile anesthetics improve postischemic cardiac function and reduce infarction even when administered for only a brief-time at the onset of reperfusion.A recent study showed that sevoflurane postconditioning (SPC)attenuated myocardial reperfusion injury, but the underlying mechanisms remain unclear,in this study,we examined the effects of sevoflurane on nitric oxide (NO)release and autophagic flux during the myocardial ischemia/reperfusion (I/R)injury in rats in vivo and ex vivo.Male rats were subjected to 30 min ischemia and 2 h reperfusion in the presence or absence of sevoflurane (1.0 minimum alveolar concentration)during the first 15 min of reperfusion.We found that SPC significantly improved hemodynamic performance after reperfusion,alleviated postischemic myocardial infarction,reduced nicotinamide adenine dinucleotide content loss,and cytochrome c.release in heart tissues.Furthermore,SPC significantly increased the phosphorylation of endothelial nitric oxide synthase (NOS)and neuronal nitric oxide synthase,and elevated myocardial NOS activity and NO production.All these effects were abolished by treatment with an NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME,10 mg/kg,i.v.).We also observed myocardial I/R-induced accumulation of autophagosomes in heart tissues,as evidenced by increased ratios of microtubule:associated protein 1 light chain 3 Ⅱ/Ⅰ,upregulation of Beclin 1 and P62,and reduced lysosome-assciated membrane protein-2 expression.SPC significantly attenuated I/R- impaired autophagic flux,which were blocked by L-NAME.Moreover,pretreatment with the autophagic flUX blocker chloroquine (10 mg/kg,i.p.)increased autophagosome accumulation in SPC-treated heart following I/R and blocked SPC-induced cardioprotection.The same results were also observed in a rat model of myocardial I/R injury ex vivo,suggesting that SPC protects rat hearts against myocardial reperfusion injury by restoring I/R-impaired autophagic flux yia an NO-dependent mechanism. 展开更多
关键词 myocardial REPERFUSION injury autophagy NITRIC OXIDE NITRIC OXIDE SYNTHASE SEVOFLURANE NG-nitro-L-arginine methyl ester CHLOROQUINE
Electrochemical performance of Al2O3 pre-coated spinel LiMn2O4
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作者 Hong-Ming Zhou Yu-Hua Zhu +2 位作者 Jian Li Wen-Jiao Sun Zhong-Zhong Liu 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第2期128-135,共8页
Al2O3-coated spinel LiMn2O4 cathode materials, presintered LiMn2O4(P-LMO), and calcined LiMn2O4(C-LMO) were synthesized by chemical deposition and thermal treating method using presintered and calcined LiMn2O4 as prec... Al2O3-coated spinel LiMn2O4 cathode materials, presintered LiMn2O4(P-LMO), and calcined LiMn2O4(C-LMO) were synthesized by chemical deposition and thermal treating method using presintered and calcined LiMn2O4 as precursors. The crystal structure, morphology,the thickness of the coating layer, and particle size of prepared samples were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), high-resolution transmission electron microscopy(HRTEM), and Malvern instruments. The average particle size of P-LMO with like-spheres(0.3 μm) is much smaller than that of C-LMO(0.5 μm). The Al2O3 layer of P-LMO can effectively reduce the charge transfer resistance and inhibit the Mn dissolution. The electrochemical performance of P-LMO is better than that of C-LMO. It is found that the LiMn2O4 cathode materials have excellent electrochemical cyclability by coated 2 mol% Al2O3 at the surface of presintered material. The initial discharge capacity of the material with 2 mol% Al2O3-coated is 114.0 m Ah·g-1 at 0.1 C rate and 55 ℃, and the capacity retention is 87.3 % at 0.5 C rate. 展开更多
关键词 Cathode materials Lithium MANGANESE OXIDE Pre-coated Aluminum OXIDE CYCLING stability
Synthesis, Crystal Structure and Antitumor Activities of 1,2,3,4-Tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) Derivatives 预览
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作者 李亦彪 杨志海 +2 位作者 王宗成 朱忠智 陈修文 《结构化学》 SCIE CAS CSCD 2019年第5期713-718,668共7页
A novel and efficient Ir-catalyzed 1,4-and 1,2-addition of diphenylphosphine oxide to quinolines was developed to obtain various 1,2,3,4-tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) derivatives. The struct... A novel and efficient Ir-catalyzed 1,4-and 1,2-addition of diphenylphosphine oxide to quinolines was developed to obtain various 1,2,3,4-tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) derivatives. The structures of these derivatives were characterized by H-RMS and NMR analysis. X-ray crystallography showed that 3 a is in a monoclinic system, space group of P21/c with a = 13.0464(16), b = 12.6244(16), c = 20.210(3)A,β= 105.215(2)o, V =3211.9(7)A^3, Z = 4, F(000)= 1352,μ= 0.42 mm^–1, S = 1.07, the final R = 0.059 and wR = 0.195.The in vitro antitumor activities of target compounds were evaluated by MTT assay against human cancer K562, HL-60, HeLa and BGC-823. The target compounds demonstrated weak or moderate antitumor activity against these cell lines. 展开更多
关键词 1 2 3 4-tetrahydroquinoline-2 4-diyl(bisdiphenylphosphine oxide) DERIVATIVES SYNTHESIS crystal structure antitumor activity
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氧化物纳米管制备工艺研究与性能比较 预览
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作者 路绍琰 张文燕 +4 位作者 武海虹 柴澍靖 骆碧君 张琦 黄西平 《应用化工》 CAS CSCD 北大核心 2019年第8期1930-1933,共4页
综述了国内外几种典型氧化物纳米管的制备方法,研究比较了不同制备方法的优缺点,评估了不同工艺的差别及对产品质量的影响,最终建议水热法作为优选的制备工艺,以促进国内氧化物纳米管的工业化生产。
关键词 氧化物 纳米管 制备方法 水热法
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Influence of coating and dew point on hearth roll pickup
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作者 Xiao-fei Zheng Yong-lin Kang Jian Zhou 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第6期647-652,共6页
Thermal spray coatings have been widely used on hearth rolls in a continuous annealing line to improve steel sheet quality and prolong the roll service life. One of the common defects formed on a working hearth roll i... Thermal spray coatings have been widely used on hearth rolls in a continuous annealing line to improve steel sheet quality and prolong the roll service life. One of the common defects formed on a working hearth roll is the oxide pickup. The most common cause of the pickup formation is that the active Mn oxide reacts with coating. The potentials of two different coatings, CoCrAlYTa-Al2O3 (No. 1) and CoCrYNi-Y2O3 (No. 2), to duplicate pickups by reacting with Fe and Mn oxides were studied. There are three stages during pickup producing and growing. No. 2 coating effectively reduced the corrosion of Mn oxide. The characterization and modification of the surface oxide formed can be changed with different dew points. The results indicate that the dew point from — 53 to — 10 ℃ can change the depth of Mn oxide, such that an alteration can prevent the first stage and second stage and is good for preventing the pickup growing. 展开更多
关键词 PICKUP COATING DEW point Surface OXIDE HEARTH ROLL
Effects of Lead on the Initial Corrosion Behavior of 316LN Stainless Steel in High-Temperature Alkaline Solution
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作者 Jia-Min Shao Cui-Wei Du +1 位作者 Xin Zhang Li-Ying Cui 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期89-97,共9页
The effect of lead on the initial corrosion behavior of 316 LN stainless steel has been investigated by U-bend immersion experiments in 4 wt% NaOH solutions at 300 °C. Follow-up studies after soaking were carried... The effect of lead on the initial corrosion behavior of 316 LN stainless steel has been investigated by U-bend immersion experiments in 4 wt% NaOH solutions at 300 °C. Follow-up studies after soaking were carried out by scanning electron microscope, energy dispersive X-ray spectrometer, X-ray photoelectron spectrometer, Auger electron spectroscopy and Raman spectroscopy. The results show that lead affects the properties of the oxide film by changing the thickness and composition, which leads to an increase in the sensitivity of stress corrosion cracking of 316 LN stainless steel. Pits and cracks appeared on the surface of 316 LN stainless steel under both lead-free and lead-containing conditions. The corrosion products were oxides of Fe, Cr and Ni, and the main spinel structure on the surface of the film was NiCr2O4 under both conditions. However, in the presence of lead, the cracks and pits were more obvious, the thickness of the film increased from 50 to 200 nm, and the amount of protective NiCr2O4 decreased. Lead was concluded to be involved in the dehydration reactions in the form of Pb(OH)2, which affected the normal dehydration process of the hydroxides and inhibited the formation of spinel structures. Because of the above characteristics of lead, the stability of the oxide film and its protection of 316 LN stainless steel were reduced. 展开更多
关键词 PbSCC OXIDE FILM 316LN High temperature
Coral?Like Yolk–Shell?Structured Nickel Oxide/Carbon Composite Microspheres for High?Performance Li?Ion Storage Anodes
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作者 Min Su Jo Subrata Ghosh +2 位作者 Sang Mun Jeong Yun Chan Kang Jung Sang Cho 《纳微快报:英文版》 CAS CSCD 2019年第1期46-63,共18页
In this study,coral-like yolk–shell-structured NiO/C composite microspheres(denoted as CYS-NiO/C)were prepared using spray pyrolysis.The unique yolk–shell structure was characterized,and the formation mechanism of t... In this study,coral-like yolk–shell-structured NiO/C composite microspheres(denoted as CYS-NiO/C)were prepared using spray pyrolysis.The unique yolk–shell structure was characterized,and the formation mechanism of the structure was proposed.Both the phase separation of the polyvinylpyrrolidone and polystyrene(PS)colloidal solution and the decomposition of the size-controlled PS nanobeads in the droplet played crucial roles in the formation of the unique coral-like yolk–shell structure.The CYS-NiO/C microspheres delivered a reversible discharge capacity of 991 mAh g?1 after 500 cycles at the current density of 1.0 A g?1.The discharge capacity of the CYS-NiO/C microspheres after the 1000th cycle at the current density of 2.0 A g?1 was 635 mAh g?1,and the capacity retention measured from the second cycle was 91%.The final discharge capacities of the CYS-NiO/C microspheres at the current densities of 0.5,1.5,3.0,5.0,7.0,and 10.0 A g?1 were 753,648,560,490,440,and 389 mAh g?1,respectively.The synergetic effect of the coral-like yolk–shell structure with well-defined interconnected mesopores and highly conductive carbon resulted in the excellent Li+-ion storage properties of the CYS-NiO/C microspheres. 展开更多
关键词 Yolk–shell Nickel oxide Carbon composite Anode materials Spray pyrolysis Lithium?ion batteries
Etomidate affects the anti-oxidant pathway to protect retinal ganglion cells after optic nerve transection 预览
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作者 Xuan Zhao Fang Kuang +2 位作者 Yi-Yan You Ming-Mei Wu Si-Wei You 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第11期2020-2024,共5页
Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is relat... Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018. 展开更多
关键词 NERVE REGENERATION ETOMIDATE retinal ganglion cells optic NERVE TRANSECTION anti-oxidative stress nitric oxide MALONALDEHYDE glutathione neural REGENERATION
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Semi-interpenetrating polymer networks toward sulfonated poly(ether ether ketone) membranes for high concentration direct methanol fuel cell
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作者 Xupo Liu Yunfeng Zhang +6 位作者 Shaofeng Deng Cuicui Li Jiaming Dong Jiaying Wang Zehui Yang Deli Wang Hansong Cheng 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期299-304,共6页
Low methanol permeability of proton exchange membranes (PEMs) is greatly important for direct methanol fuel cells (DMFCs). Here, sulfonated poly (ether ether ketone) (SPEEK) based semiinterpenetrating polymer networks... Low methanol permeability of proton exchange membranes (PEMs) is greatly important for direct methanol fuel cells (DMFCs). Here, sulfonated poly (ether ether ketone) (SPEEK) based semiinterpenetrating polymer networks (semi-IPNs) are successfully prepared by interpenetrating SPEEK into the in-situ synthesized crosslinking networks. The polymeric networks are formed by the covalent bonds between bromobenzyl groups of bro mo methylated poly (phenylene oxide) and amine groups of diamine linkers as well as the ionic bonds between amine species and sulfonated groups. Two linkers without and with sulfonated groups are applied to fabricate the semi-IPNs. The core properties of the membranes, like phase separation, water uptake, proton conductivity and methanol permeability, are systematically studied and compared. The DMFCs assembled by using the semi-IPN membranes display better performance than Nafion 117 in high concentration methanol solutions. The present work provides a facile way to prepare PEMs with enhanced DMFC performance. 展开更多
关键词 Direct methanol fuel cell PROTON exchange membrane Semi-interpenetrating polymer networks SULFONATED poly(ether ETHER ketone) Bromomethylated poly(phenylene oxide)
Carbon deposition in porous nickel/yttria-stabilized zirconia anode under methane atmosphere 预览
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作者 Zhi-yuan Chen Li-jun Wang +3 位作者 Xiao-jia Du Zai-hong Sun Fu-shen Li Kuo-Chih Chou 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期350-359,共10页
A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exc... A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exceeded 700℃. The reactivity of carbon decreased with increasing deposition temperature. Filamentous carbon was deposited from 400 to 600℃, whereas flake carbon was deposited at 700 and 800℃. With increasing temperature, the intensity ratio of the D band over the sum of the G and D bands was constant at the beginning and then decreased with the transformation of the carbon morphology. The crystallite size increased from 2.9 to 13 nm with increasing temperature. The results also indicated that the structure of the deposited carbon was better ordered with increasing deposition temperature. In comparison with pure Ni powders, the interaction between the YSZ substrate and Ni particles could not only modify the carbon deposition kinetics but also reduce the temperature effect on the structure and reactivity variation of carbon. 展开更多
关键词 solid oxide FUEL cell COKING RAMAN spectrum HYDROCARBON FUEL ANODE
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Structure,rheology and electrospinning of zein and poly(ethylene oxide) in aqueous ethanol solutions
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作者 Ce Shi Shixia Xi +3 位作者 Yingchun Han Hao Zhang Jingsheng Liu Yunqi Li 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期305-310,共6页
Electrospun fiber mats (EFM) integrated proteins and biocompatible polymers have been widely used as tissue scaffold, wound dressing and food packaging. The morphology of EFM has strong correlation with the structure ... Electrospun fiber mats (EFM) integrated proteins and biocompatible polymers have been widely used as tissue scaffold, wound dressing and food packaging. The morphology of EFM has strong correlation with the structure and rheology of the solutions. We studied the structure and rheology of polyethylene oxide (PEO) and zein in 80% ethanol aqueous solutions and the resulted EFM. In solutions, zein with rod-like conformation tends to aggregate and form oligomer, the number of proteins in the oligomer spans from 2.5 to 55.2, while PEO always behaves like Gaussian chain in good solvent. Zein preferred to distribute along PEO chains in their mixed solutions, and the structures decomposed from small angle X-ray scattering have consistent relaxation spatial-temporal characteristics with rheological behaviors.Further, the aging of zein solutions enhanced shear thinning and resulted thicker fibers in EFM, which are attributed to the rod-like growth of zein aggregates. Aggregates in viscous media with long enough relaxation time are probably crucial for the formation of continuous electrospun fibers or ribbons. This study provides a clear correlation of the structure, rheology of solutions with the morphologies of EFM made up of proteins and polymers. 展开更多
关键词 Small angle X-ray SCATTERING ZEIN Poly(ethylene oxide) Viscosity Electrospin
Novel BiVO4@C3N4@GO Composites with Higher Photocatalytic Performance 预览
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作者 Liu Yanxiu Guo Zhi +3 位作者 Wang Lijuan Lyu Wenxue Song Hua Wang Xueqin 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第2期50-57,共8页
BiVO4, BiVO4@C3N4 and BiVO4@C3N4@GO composite photo-catalysts were synthesized, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), transmission elec... BiVO4, BiVO4@C3N4 and BiVO4@C3N4@GO composite photo-catalysts were synthesized, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) surface area techniques. The photocatalytic activity was evaluated on the degradation of methylene blue (MB) under visible light irradiation, which denoted that the BiVO4@C3N4@GO ternary composite outperformed the binary composite BiVO4@C3N4 and BiVO4. Then the effects of catalyst dosage, initial pH value, and initial methylene blue concentration on the degradation process were investigated systematically. The improvement of visible-light photocatalytic degradation performance was attributed to the enhanced visible light absorption, larger surface area, higher adsorption ability, and prolonged lifetime of photo-generated electron-hole pairs. The recycle experiments results showed that the BiVO4@C3N4@GO composite had excellent photo-stability for MB photocatalytic degradation. 展开更多
关键词 BIVO4 C3N4 graphene OXIDE VISIBLE light PHOTOCATALYST
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Improved electrochemical performance of Li(Ni0.6Co0.2Mn0.2)O2 at high charging cut-off voltage with Li1.4Al0.4Ti1.6(PO4)3 surface coating
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作者 王怡 刘柏男 +4 位作者 周格 聂凯会 张杰男 禹习谦 李泓 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期446-452,共7页
Ba0.8Sr0.2FeO3-δhas been surface-modified by the lithium-ion conductor Li1.4Al0.4Ti1.6(PO4)3via a facile mechanical fusion method. The annealing temperature during coating process shows a strong impact on the surface... Ba0.8Sr0.2FeO3-δhas been surface-modified by the lithium-ion conductor Li1.4Al0.4Ti1.6(PO4)3via a facile mechanical fusion method. The annealing temperature during coating process shows a strong impact on the surface morphology and chemical composition of Li(Ni0.6 Co0.2 Mn0.2)O2. The 600-?C annealed material exhibits the best cyclic stability at high charging cut-off voltage of 4.5 V(versus Li+/Li) with the capacity retention of 90.9% after 100 cycles, which is much higher than that of bare material(79%). Moreover, the rate capability and thermal stability are also improved by Li1.4Al0.4Ti1.6(PO4)3coating. The enhanced performance can be attributed to the improved stability of interface between Ba0.8Sr0.2FeO3-δand electrolyte by Li1.4Al0.4Ti1.6(PO4)3modification. The results of this work provide a possible method to design reliable cathode materials to achieve high energy density and long cycle life. 展开更多
关键词 LITHIUM-ION batteries cathode Ni-rich oxide solid electrolyte coating
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