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1.
A Box-Behnken design(BBD) of response surface methodology(RSM) was used to optimize the preparation of the Zn-Sm antibacterial white carbon black by the sol-gel method. The statistical analysis of the results showed that the particle size of the Zn-Sm antibacterial white carbon black was significantly affected by the reaction time, reaction temperature and the stirring speed. According to analysis of variance(ANOVA), the values of the determination coefficient(R2=0.9821) and the "Pred R-Squared" of 0.8227 were in reasonable agreement with the "Adj R-Squared" of 0.9591. It was indicated that this model could be used to navigate the design space. The optimized reaction time, temperature and the stirring speed were 0.88 h, 87.83 oC, and 473.45 r/min, respectively. In addition, the bacteriostasis rate of the product was about 97.92%. 相似文献
2.
Mechanism of antibacterial activity of silver and praseodymium-loaded white carbon black 总被引:1,自引:0,他引:1
This paper investigated the antibacterial mechanism of the Ag-Pr-antibacterial white carbon black.The sol-gel method was used to prepare the carrier:white carbon black.Silver ion was selected to be the antibacterial ion,and praseodymium nitrate was selected to be the additive.The structure and antibacterial mechanism of this new inorganic antibacterial material were characterized by laser particle size analyzer,scanning electron microscope(SEM) techniques,energy dispersive spectrum(EDS) analysis,and antibacterial activity test(Escherichia coli as experimental bacterium).Results showed that the particle size of Ag-Pr-antibacterial White carbon black was less than 30 μm with a narrow size distribution.Ag+ is combined into the white carbon black by both the mode of ion exchange and the mode of adsorption process.The bacteriostasis rate of the Ag-Pr-antibacterial white carbon black was higher than that of the general Ag-antibacterial white carbon black.The antibacterial activity of Ag-Pr-antibacterial white carbon black was caused by the combination of contact and stripping antibacterial mechanism.The result also indicated that this new inorganic antibacterial material had good thermal and light stability. 相似文献
3.
A novel kind of magnetically separable photocatalyst of cerrium-doped mesoporous titanium dioxide coated magnetite (Ce/MTiO2/ Fe3O4) was prepared and its activities under UV and visible light were reported. The catalysts with Ce/MTiO2 shell and Fe3O4 core were pre-pared by coating photoactive Ce/MTiO2 onto a magnetic Fe3O4 core through the hydrolysis of tetrabutyltitanate (Ti(OBu)4, TBT) with pre-cursors of ammonium ceric nitrate and TBT in the presence of Fe3O4 particles. The MTiO2 shell was for photocatalysis, the Fe3O4 core was for separation by the magnetic field and the doped Ce was used to enhance the photocatalytic activity of MTiO2. The morphological, struc-tural and optical properties of the prepared samples were characterized by Brunauer-Emmett-Teller (BET) surface area, transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-vis absorption spectroscopy. The effect of cerrium-doped content on the photocatalytic activity was studied and the result revealed that 0.5 mol.% Ce/MTiO2/Fe3O4 exhibited highest photoactivity. The photocatalytic activities of obtained photocatalysts under UV and visible light were estimated by measuring the degradation rate of methylene blue (MB, 50 mg/L) in an aqueous solution. The results showed that the prepared photocatalyst was activated by visible light and used as effective catalyst in photooxi-dation reactions. In addition, the possibility of cyclic usage of the prepared photocatalyst was also confirmed. Moreover, Ce/MTiO2 was tightly bound to Fe3O4 and could be easily recovered from the medium by an external magnetic filed. So, the photocatalyst can be reused without any mass loss. It can therefore be potentially applied for the treatment of water contaminated by organic pollutants. 相似文献
4.
In this paper a kind of new inorganic antibacterial material:Cu-antibacterial white carbon black containing lanthanum was synthesized.The characterization and antimicrobial effect of the Cu-antibacterial white carbon black containing lanthanum was investigated.Inorganic antibiotic materials comprised the carrier,the antibacterial ion and the additive.In this study,we choosed white carbon black as the carrier,which was compound by a sol-gel method.Copper ion was selected to be the antibacterial ion,and lanthanum nitrate was selected to be the additive.The as-synthesized Cu-La-antibacterial white carbon black was characterized by inductively coupled plasma(ICP),laser particle size analyzer,Fourier transform infra-red spectroscopy(FT-IR) and antibacterial activity test(Escherichia coli as experimental bacterium).Results showed that the amount of antibacterial ions of the Cu-La-antibacterial white carbon black was higher than that for the general Cu-antibacterial white carbon black.Its bacteriostasis rate was about 98%(when the content of Cu2+ was about 3%),and corresponded to Ag-antibacterial white carbon black(99%).The particle size of Cu-La-antibacterial white carbon black was under 30 μm with a narrow size distribution.Copper ion was bound to white carbon black by ion exchange process.Moreover,this new inorganic antibacterial material showed promising result on the coating surface of metal. 相似文献
5.
The self-assembly of HL(L=[5-(ethoxycarbonyl)-4-phenyl-3,4-dihydropyrimidin-2(1H)-one-6-yl]methanesulfonate) with Sm(ClO4)3·6H2O yielded a 2D coordination polymer {[SmL3(H2O)2]·4H2O}n(1).Its crystallographic data indicated that it belonged to a triclinic system,space group P-1,a=1.42233(8),b=1.47155(8),c=1.53868(9) nm,α=8.62710(10),β=6.35250(10),γ=71.5790(10)°,V=2.7241(3) nm3,Z=2,R1=0.0693,wR2=0.1054.X-ray analysis revealed that the local coordination environment around Sm(III) was a slightly distorted dodecahedron in which Sm center was eight-coordinate geometry with eight oxygen atoms from three sulfonic groups,three carbonyl groups and two aqua ligands.Each L-acted as a bidentate spacer to link two Sm centers,resulted in the formation of a 2D hexagonally grid network.The discrete 2D planes in 1 were assembled into a 3D supramolecular network via strong hydrogen bonds among noncoordinated aqua O atoms,coordinated aqua O atoms,and noncoordinated O atoms of sulfonic groups and carbonyl groups.Furthermore,this metal-organic polymer exhibited strong photoluminescence maximized at 379 nm upon 274 nm excitation in the solid state at room temperature. 相似文献
6.
A novel supported polyoxometalate(POM),phosphotungstic acid immobilized into yttrium-doped TiO2(HPW-Y-TiO2) nano photocatalyst was prepared via sol-gel and impregnation method.The samples were characterized using Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD) and N2 absorption-desorption analysis.The results showed that the supported POM exhibited Keggin structure and anatase phase with large BET surface area.The influences of inorganic anions and organic additives on the photocatalytic degradation of azo dye methyl orange with HPW-Y-TiO2 as photocatalyst under UV light(λ≥365 nm) were investigated.Results showed that inorganic anions Cl-,SO42-,CO32-and NO3-had inhibition effect on the degradation of methyl orange.A great enhancement of degradation rate was obtained while H2O2 and ethyl alcohol were applied.The degradation rates improved with the increase of H2O2 concentration.The optimum additive amount of ethyl alcohol was 0.5 mol/L.The possible mechanisms of the effects of additives on methyl orange degradation were discussed. 相似文献
7.
WU Xiaohong SU Peibo LIU Huiling QI Lili 《中国稀土学报(英文版)》2009,27(5):739-743
Microporous titanium dioxide films were prepared by the sol-gel methods on glass substrates, using tetrabutyl titanate as source material. In order to absorb the visible light and increase the photocatalytic activities, different concentrations of neodymium ions (Nd/Ti molar ratio was 0.5%, 0.7%, 0.9%, and 1.1% respectively) were added into the sol. X-ray diffraction (XRD), X-ray photoelectron spectros-copy (XPS), and atom force microscopy (AFM) were applied to characterize the modified films. A kind of typical textile industry pollutant (Rhodamine B) was used to evaluate the photocatalytic activities of the films under visible light. The results showed that the activities of the films were improved by doping Nd ions into the sol. 相似文献
8.
The microstructure and mechanical properties of AZ61 magnesium alloy with Ca, Sm addition were investigated. The results showed that the addition of 0.5 wt.% Ca reduced the quantity of Mg17Al12 phase, and formed a new Al4 Ca phase which is reticular in AZ61 alloy. With the addition of Ca and Sm, the microstructure was further refined and new Al-Sm rich phases were formed in AZ61 alloy with 0.6 wt.%–1.5 wt.% Sm addition, the TEM analysis confirmed that they were Al2 Sm and Al4 Sm. Tensile tests showed that 1.0 wt.% Sm addition contributed to the formation of the Al2 Sm and Al4 Sm and the improvement in the ambient strength, i.e., an ultimate tensile strength of 327 MPa and an elongation of 10.1%. However, excessive Sm addition led to the coarsening of Al2 Sm and Al4 Sm phases, thus resulted in the decline of strength and plasticity. 相似文献
9.
The nanocomposite materials containing rare earths, titanium dioxide and clay (RE/TiO2/Clay) were characterized and tested for the photocatalytic decomposition of formaldehyde. The results show that nanocomposite materials prepared by doping appropriate rare earth elements have better photocatalytic properties than that prepared by doping excessive rare earth elements. The photocatalytic mechanism of composite materials was studied by integrating the theory of photocatalysis with experiment results. Because the site of photocatalytic reaction was limited in the interspace of clay, photocatalytic reaction occurred by two steps: firstly, organic molecules dispersed into the interlayers of clay; secondly, organic molecules and photocatalyst of RE/TiO2 occurred photocatalytic reaction, resulting in forming carbon dioxide. 相似文献
10.
Alexander A.Maleev Anatoly P.Pushkarev Vasily A.Ilichev Mikhail A.Lopatin Maxim A.Samsonov Georgy K.Fukin Georgy L.Pakhomov Vladislav V.Travkin Ivan D.Grishin Mikhail N.Bochkarev 《中国稀土学报(英文版)》2014,32(12):1101-1108
The monophthalocyanine complexes of samarium and terbium containing axial 2-mercaptobenzothiazole(Pc Sm(MBT)(1)), 2-(2-benzoxazol-2-yl) phenolate(Pc Tb(OON)(2)) or 2-(2-benzothiazol-2-yl)phenolate(Pc Tb(SON)(3)) ligands were synthesized and identified by elemental, LDI-TOF and X-ray(for 1) analysis.Photoluminescence(PL) and electroluminescence(EL) spectra of the compounds contained only emission bands of phthalocyanine and axial ligands but did not contain the bands of f-f transitions.It was found that among the complexes 1, 2, 3 the latter had highest photoconductivity(~10–7 S/cm) and photovoltaic properties.An organic photovoltaic device(OPV) of configuration of ITO/3/C60/Alq3/Al revealed open-circuit voltage(VOC) of 0.24 V and short current density(ISC) of 0.3 μA/cm2 under illumination by a xenon lamp at 17 m W/cm2. 相似文献
11.
Preparation and Photocatalytic Property of Er_2O_3/TiO_2 Complex Photocatalyst 相似文献
12.
The Ce-TiO2/KL (diatomite) ball photocatalyst was prepared and characterized based on the pretreated diatomite. The resuits showed that comparing with the crude diatomite, proper pretreatment could significantly improve its SiO2 purity and specific surface area. The surface of diatomite was clear with uniform pore structure and big pore size. With diatomite ball as carder, the supported Ce-TiO2/KL ball photocatalyst was prepared by sol-gel method. The photocatalytic performances of the supported Ce-TiO2/ KL ball and Ce-TiO2/KL powder photocatalysts under various preparation conditions were studied in view of photocatalytic degrada- tion rate of Rhodamine B (Rh B) solution. The degradation rate of the ball photocatalysts for Rh B reached 94.6% and could be reused for many times, which showed much better photocatalytic performance and stability than powder photocatalysts. 相似文献
13.
14.
AlargenumberofM0 .5A0 .5M′O4 (M :rareearthion ,Bi3+,Fe3+,Cr3+,etc .A :alkaliion ,Cu+,Ag+,etc .M′ :Mo ,W )withtetragonalscheelite typestructurehavegoodcatalyticproperties .Aslumines centsubstrates ,theyhaveexcellentsensitizationtolu minescenceofrareearthion .Manyresearchesontheirstructure ,catalytic ,magneticandluminescentproper tieshavebeenmadesince 196 0s[1~ 10 ] .Thegeneralformulaforcompoundswiththetetragonalscheelite typestructureisAM′O4 wherethecationM′istetrahe drallycoordinat… 相似文献
15.
A series of zinc ions or/and cerium ions co-doped α-zirconium phosphate (Zn-Ce@ZrPs) were prepared. The novel Zn-Ce@ZrPs were characterized and the antibacterial activity on Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus were tested. The results showed that zinc ions (Zn2+) or/and cerium ions (Ce3+) were combined with ZrP, and the Ce3+ was adsorbed on the surface of ZrP through hydrogen bonds, while Zn2+ intercalated into the interlayer of ZrP. Zn-Ce@ZrPs showed excellent synergistic antibacterial activity. When Zn2+/Ce3+ atomic ratio was 0.6, the Zn-Ce@ZrP3 showed the highest synergistic antibacterial efficiency, suggesting great potential application as antibacterial agents in microbial control. 相似文献
16.
Preparation, Characterization and Photo-Catalytic Behavior of Y_2O_3/TiO_2 Composite Semiconductor Nanopowder 总被引:3,自引:0,他引:3
TiO2 photo catalysishasbeenafocusofnumerousinvestigationsinrecentyears ,par ticularlyowingtoitsapplicationforthecom pletemineralizationofundesirableorganiccon taminantstoCO2 ,H2 Oandinorganiccon stituent[1] .However,photo oxidationisalmostnotindustriallyapplie… 相似文献
17.
OUYANG Yousheng XIE Yushan TAN Shaozao SHI Qingshan CHEN Yiben 《中国稀土学报(英文版)》2009,27(5):858-863
Four kinds of Ce3+ exchanged montmorillonites(Ce/MMTs) were prepared by an ion-exchange reaction, and characterized with energy dispersive X-ray analysis (EDX), X-ray difference (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron micros-copy (SEM). The surface properties and antibacterial activity of Ce/MMTs were also investigated. The chemical compositions of Ce/MMTs were determined, and the cerium of Ce/MMTs was confirmed to be present as trivalent cerium state. The d001 basal spacings of Ce/MMTs were enlarged with the enhancement of the cerium contents, and the particles were formed with irregular shape. On increasing the Ce con-tents of Ce/MMTs, the special surface areas were decreased, but the total pore volumes and the average pore sizes were increased. The anti-bacterial activity of Ce/MMTs is increased with increasing the cerium contents, and 1.5g/L of Ce/MMT-3 containing 11.46wt.% of curium could remove all the Staphylococcus aureus and more than 99.9% of the Escherichia coli within 24.0 h of contact. Moreover, Ce/MMTs dis-played bactericidal activity. 相似文献
18.
Rare earth phosphate core/shell nanostructures were synthesized via facile ultrasound irradiation method.XRD and TEM were em-ployed to characterize the structure and morphology properties.The photoluminescence(PL) properties of TbPO4/CePO4 and CePO4/TbPO4 core/shell nanorods were studied to explore the energy transfers from Ce3+ to Tb3+.In the Ce0.9Tb0.1PO4/LaPO4 core/shell nanorods,the PL intensity of Ce0.9Tb0.1PO4 nanorods was enhanced when the LaPO4 shells were coated. 相似文献
19.
Synthesis, characterization, and biological properties of nano-rare earth complexes with L-glutamic acid and imidazole 总被引:1,自引:0,他引:1
Four nano-rare earth ternary complexes of L-glutamic acid and imidazole RE(Glu)3ImCl3·3H2O (RE=Ce^3+, Pr^3+, Sm^3+, Dy^3+, Glu= L-glutamic acid, and Im=imidazole) were synthesized. Their composition was characterized with elemental analysis, IR, and molar conductance. The TEM image indicated that the complexes were regular shaped and the length was about 30-60 nm. The antibacterial activity test showed that all these complexes exhibited better antibacterial ability against Escherichia coli, Staphylociccus aureus, and Candida albican (MIC were about 180, 100, and 310 μg/mi, respectively) and could be considered as broad-spectral antimicrobial. Their antitumor activity in vitro against leukemia K562 cells was measured using the MTr method. The results indicate that the four complexes possess strong inhibi- tion effect on leukemia K562 cells. An approximately linear relationship is discovered between the relative inhibition rate and concentration, with the correlation coefficients R〉0.7 and P〈0.05, which is considered statistically significant. 相似文献
20.
Sinceaza crownethershowsspecialcoordinationpropertiestotransitionmetalandheavymetalions[1,2 ] ,therearemanyreportsofthecomplexesinhost guestchemistry ,molecularrecognition[3 ,4] andionophoreinmembranetransportation[5] ,butthereislittlereportontheirrareearthscomplexesandthefluorescenceaboutthecomplexes[6] ,andthefluorescenceintensityoftheircomplexesarenotverystrong .Weinsetbenzoylgroupintothemacrocycle ,expectingthatitsrareearthscomplexeshavebetterfluorescenceproperties .Inthispaperthesynthesis… 相似文献