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排序方式: 共有240条查询结果,搜索用时 31 毫秒
61.
Selective removal of nitrate by using a novel macroporous acrylic anion exchange resin 总被引:1,自引:0,他引:1
Sandra Mueller 《中国化学快报》2012,23(5):603-606
An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO42-/ NO3- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features. 相似文献
62.
The binary random in-chain silyl-hydride multi-functionalized poly(styrene/butadiene/isoprene and dimethyl[4-(1-phenylvinyl) phenyl]silane)(PS-DPESiH,PB-DPESiH,PI-DPESiH) copolymers were successfully synthesized.These functionalized copolymers were prepared in hexane with n-BuLi as the initiator at 50℃for 4 h.The silyl-hydride groups were introduced into polymer backbones quantitatively by living anionic polymerization.The copolymers were determined through ’H NMR,size exclusion chromatography(SEC) and differential scanning calorimetry(DSC) techniques,while the number of silyl-hydride groups was calculated and discussed. 相似文献
63.
Giordano C Saino E Rimondini L Pedeferri MP Visai L Cigada A Chiesa R 《Colloids and surfaces. B, Biointerfaces》2011,88(2):648-655
Bacterial contamination of implanted devices is a common cause of their failure. The aim of the present study was to assess the capability of electrochemical procedures to: (a) promote the formation of anatase on the surface of commercially pure Grade 2 Ti and Ti Grade 5 (Ti6Al4V) alloy; (b) inhibit in vitro biofilm formation of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans and Porphyromonas gingivalis and oral plaque in vivo, (c) preserve favorable response of osteoblasts and fibroblasts to materials surfaces. Ti Grade 2 and Ti Grade 5 were respectively anodized at two different voltages: 90 and 130V for pure titanium; 100 and 120V for Ti6Al4V alloy. Surface characterization was performed by scanning electron microscopy (SEM) equipped with EDS probe, laser profilometry and X-ray diffractometry. Bacterial adhesion characterization was performed either in vitro and in vivo in patients. Osteoblast and fibroblast response was evaluated by metabolic activity assessment. The higher voltage applied in the anodization treatment of pure titanium (130V) and Ti6Al4V alloy (120V) surfaces, compared to the untreated pure titanium and Ti6Al4V and to lower voltage treatments, resulted in a greater decrease in bacterial attachment and biofilm formation in both in vitro and in vivo experiments. In contrast, the high voltage treatments were found to promote osteoblasts and fibroblasts proliferation. The observations indicated that the experimented high voltage anodization treatments may contribute to preserve the tissue integration and reduce bacteria colonization of titanium and titanium alloy for implantable applications. 相似文献
64.
The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed Sonogashira reaction in the absence of copper and amine.The coupling of various aryl bromides and aryl chlorides with phenylacetylene gave moderate to excellent yields. 相似文献
65.
Cross-linkedβ-cyclodextrin polymer/Fe3O4 composite nanoparticles with core-shell structures were prepared via cross linking reaction on the surface of carboxymethylβ-cyclodextrin(CM-β-CD) modified Fe3O4 nanoparticles inβ-cyclodextrin alkaline solution by using epichlorohydrin as crosslinking agent.The morphology,structure and magnetic properties of the prepared composite nanoparticles were investigated by transmission electron microscopy(TEM),Fourier transform infrared(FTIR) spectrometry,X-ray diffraction(XRD) measurement,thermogravimetric analysis(TGA) and Vibrating sample magnetometry (VSM),respectively. 相似文献
66.
Ming Ming Yu Xia Li Miao Luan Jun Na Gao Qiu Zhi Shi Ming Sheng Tang Liu He Wei 《中国化学快报》2010,21(10):1157-1161
<正>An improved strategy for the synthesis of 3,3'-(oxy-p-phenylene)bis(2,4,5-triphenylcyclopentadienone) was developed,which includes three steps:Friedel-Crafts reaction,oxidation and condensation.Importantly,the use of KMnO_4 made the second step simple and efficient,which has potential application to synthesis of bis(cyclopentadienone)s.The course of oxidation has been confirmed by isolated intermediates. 相似文献
67.
Synthesis and application of a hydrophobic hypercrosslinked polymeric resin for removing VOCs from humid gas stream 总被引:1,自引:0,他引:1
A hydrophobic hypercrosslinked polymeric resin LC-1 was prepared and characterized.The properties of LC-1 resin were compared with those of a commercial hypercrosslinked polymer NDA-201 resin.In addition,the dynamic adsorption of trichloroethylene(TCE)onto LC.1 under dry and humid conditions at 303 K was investigated,the result shows that LC-1possesses high hydrophobic property and can remove TCE from gas stream without effect of high humidity efficiently. 相似文献
68.
Jian Feng Liu Kang Ping Xu De Jian Jiang Fu Shuang Li Jian Shen Ying Jun Zhou Ping Sheng Xu Bin Tan Gui Shan Tan 《中国化学快报》2009,20(5):595-597
6-(2-Hydroxy-5-acetylphenyl)-apigenin (1),a new flavonoid with a phenyl substituent,was first isolated from Selaginella tamariscina.Its structure was elucidated on the basis of 1D and 2D NMR as well as ESI-HR-MS spectroscopic analysis. 相似文献
69.
In an attempt to search for more potent positive inotropic agents,a series of 1-(benzylamino)-3-(4,5-dihydro[1,2,4]trizaolo[4,3- a]quinolin-7-yloxy)propan-2-ol derivatives was synthesized in four steps using 6-hydroxy-3,4-dihydro-2(1H)-quinolinone as a starting material,and their positive inotropic activities were evaluated by measuring the coronary blood flow(CBF)and the left ventricular pressure(LVP)followed by calculating the rate of pressure development(dp/dt_(max)values)in the preparation of rat Lan... 相似文献
70.
A Keggin-type tungstosilicate compound [Co^Ⅱ(2,2′-bipy)2(H2O)]2[SiW^Ⅵ12O40]·2H2O 1 (bipy = bipyridine) was prepared by a hydrothermal method for the first time. Single-crystal X-ray diffraction revealed that 1 (C40H40Co2N8O44SiW12) crystallizes in the triclinic system, space group P1 with a = 10.4979(6), b = 13.3946(7), c = 13.5756(8)A, α= 70.0769(18), β = 68.910(3), γ = 74.186(4)°, V = 1649.84(16)A^3, Mr = 3688.95, Z = 1, Dc = 3.713 mg·m^-3, μ = 21.432 mm^-1, F(000) = 1644, S = 1.058, the final R = 0.0511 and wR =0.1023 for 6523 observed reflections (I 〉 2σ(I)). Compound 1 consists of two coordinated cation fragments [Co^Ⅱ(2,2′-bipy)2(H2O)]^2+, one normal Keggin polyanion unit [SiW^Ⅵ12O40]^4- and two lattice water molecules. To be noted, each polyanion unit is linked to two cation fragments by its two surface terminal oxygen atoms and two cobalt atoms of two cation fragments forming an organic-inorganic hybrid unit in 1. Furthermore, the compound shows strong photoluminescence property in the solid state at room temperature. 相似文献