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201.
202.
Regenerated cellulose films with water-resistance were obtained by an improved method ofpreparing cellulose cuoxam solution from pulps of agricultural wastes (linters, wheat straw, reedand Bamao). Experimental results showed that the mechanical properties of both the dry. and wetfilms were excellent. Data from IR, SEM and tensile strength measurements implied that thesignificant improvement of water-resistance of the films was due to the cohesion between the thinTung oil covers with hydrophobicity and the regenerated cellulose films. The films werecompletely biodegraded after being buried in soil for 100 days. The transmittance of the filmsderived from linter and reed in visible band range were 80-90%. 相似文献
203.
Metal (M) oxide (M: Ir, Os, Pd, Pt, Rh, Ru) together with MaO2 and MnO2 alone, were coated on SnO2 films and the anode behavior was examined in 1.0 N H2SO4, 1.0 N NaOH and 1.0, N NaCl aqueous solutions at 25°. The results are compared with those of DSA and of metallic Pt. 相似文献
204.
The nano-ZnFe2O4/TiO2 films possess the functions of desulfurization and degradation for organic pollutants. The sols of ZnFe2O4/TiO2 were prepared by sol-gel method and coated on glass and porous ceramic by vertical coating and dipping-lift processes, respectively, and the samples were obtained after drying and sintering. The composition, appearance, absorption spectrum of the films, and the influence of the film on porous ceramic performances were analyzed using SEM, AFM, UV-Vis spectrometer, and mercury porosimeter, respectively, to determine the operation parameters of the multifunction porous ceramic elements for gas-purification. 相似文献
205.
206.
Electropolymerized thin films of Co(III/II)- and Zn(II)-4,9,16,23-tetraaminophthalocyanine, immersed in solutions of relatively high pH, have been studied electro- and spectroelectrochemically. Cyclic voltammetry and chronocoulometry were used to characterize films deposited on glassy carbon electrodes. Spectroelectrochemistry and ellipsometry measurements were performed on indium tin oxide (ITO) surfaces coated with the zinc and cobalt complexes and correlated to the electrochemical information collected using glassy carbon electrodes. Studies at high pH are motivated by the efficient increase in luminol chemiluminescence at high OH− concentration, and by potential application in luminescence sensors. Although the films are not removed, some structural changes occur when they are exposed to solutions of high pH. In addition, an estimation of the number of monolayers has also been calculated. The atomic diameters of cobalt and zinc are very close in value, but the estimated number of monolayers, based on cyclic voltammetric data, for a given number of electropolymerization cycles is approximately four-fold higher in the zinc-based film. This would correspond to three-fold thicker films when zinc is the central metal ion. Ellipsometry measurements have been correlated with cyclic voltammetric data to confirm that film thickness varies among the different complexes, even though the conditions of electropolymerization are the same. 相似文献
207.
p—Si上电沉积Ni—W—P薄膜的结构与热稳定性 总被引:3,自引:0,他引:3
研究了p-Si上恒电流沉积Ni-W-P合金薄膜组成与结构的关系,讨论了镀层的组成、结构随沉积时间的变化.测定了非晶合金的晶体结构随热处理温度的改变以及DTA曲线,结果表明,非晶Ni-W-P合金在晶化过程中形成两个纳米超微晶相,非晶Ni-W-P薄膜的热稳定性远高于通常使用的非晶Ni-P薄膜. 相似文献
208.
209.
Fabrication of high performance thin films from metal fluorocomplex aqueous solution by the liquid phase deposition 总被引:1,自引:0,他引:1
Hnin Yu Yu Ko Minoru Mizuhata Akihiko Kajinami Shigehito Deki 《Journal of fluorine chemistry》2003,120(2):157-163
The hetro-structured oxide thin films from metal fluorocomplex solution have been prepared by the liquid phase deposition (LPD) method. The Pt/Nb2O5 and Au/Nb2O5 composite films can be prepared from a mixed solution of niobium source, H3BO3, Pt(NH3)4Cl2 and HAuCl4 aqueous solutions under the ambient temperature and atmosphere. In the case of Au/SiO2 composite film, (NH4)2SiF6 solution is used as a mother solution. The Pt and Au ionic species are deposited in Nb2O5 and SiO2 matrices. They are reduced to their metallic state after treatment above 200 °C. The size of dispersed particles can be controlled by heat treatment temperature. It is also clear that, gold nanoparticles are also found to interact with SiO2, although the interaction is smaller than that with Nb2O5 showing the size of Au nanoparticles remain smaller in Nb2O5 that in SiO2. 相似文献
210.
Lili Hu Marcus Wolf Michael Grätzel Zhonghong Jiang 《Journal of Sol-Gel Science and Technology》1995,5(3):219-226
The hydrolysis of niobium pentaethoxide precursor in the presence of triethylamine (TEA) is discussed. Three precursors with TEA/Nb(OEt)5 mole ratios of 0.25, 0.4 and 0.8 were prepared. Niobia colloids with different appearance were obtained after autoclaving the above precursors at 250°C during 12 h. The surface roughness and microstructure of niobia films prepared with the colloids by spread coating method are strongly dependent on the TEA/Nb(OEt)5 mole ratio. At a value of 0.4 TEA/Nb(OEt)5 mole ratio, a niobia film with large surface roughness can be achieved. It is opaque and mechanically stable and has differently ordered needle microstructure. The crystalline structure and photoelectrochemical property of niobia film with the largest surface roughness were examined. The effect of CO2 gas bubbling, reflux and addition of 2-methoxyethanol on the hydrolysis of Nb(OEt)5 and the nature of the Nb2O5 films is also discussed. 相似文献