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排序方式: 共有157条查询结果,搜索用时 15 毫秒
11.
Kazuo Umemura Ryo Hamano Hiroaki Komatsu Takashi Ikuno Eko Siswoyo 《Molecules (Basel, Switzerland)》2021,26(10)
Solubilization of carbon nanotubes (CNTs) is a fundamental technique for the use of CNTs and their conjugates as nanodevices and nanobiodevices. In this work, we demonstrate the preparation of CNT suspensions with “green” detergents made from coconuts and bamboo as fundamental research in CNT nanotechnology. Single-walled CNTs (SWNTs) with a few carboxylic acid groups (3–5%) and pristine multi-walled CNTs (MWNTs) were mixed in each detergent solution and sonicated with a bath-type sonicator. The prepared suspensions were characterized using absorbance spectroscopy, scanning electron microscopy, and Raman spectroscopy. Among the eight combinations of CNTs and detergents (two types of CNTs and four detergents, including sodium dodecyl sulfate (SDS) as the standard), SWNTs/MWNTs were well dispersed in all combinations except the combination of the MWNTs and the bamboo detergent. The stability of the suspensions prepared with coconut detergents was better than that prepared with SDS. Because the efficiency of the bamboo detergents against the MWNTs differed significantly from that against the SWNTs, the natural detergent might be useful for separating CNTs. Our results revealed that the use of the “green” detergents had the advantage of dispersing CNTs as well as SDS. 相似文献
12.
竹木质素的红外光谱与X射线光电子能谱分析 总被引:2,自引:0,他引:2
应用傅里叶转换红外光谱(FTIR)和X射线光电子能谱(XPS), 研究了3种提纯方法得到的竹木质素及其化学反应产物的化学结构特性. 确定竹木质素C1s的电子结合能分别为283.52 (C—H或C—C), 284.58~285.72 (C—OR或C—OH), 286.10~286.44 (C=O或HO—C—OR), 287.65~287.72 (O—C=O) eV. O1s的电子结合能分别为530.31(羟基氧原子), 531.45~531.72(醛或酮的羰基氧原子), 532.73~533.74(酯键或羧酸中的羰基氧原子) eV. 竹木质素中的结构单元之间主要是通过醚键和碳碳单键连接, 慈竹磨木木质素结构单元中醚键、碳碳单键、酯键、羰基和烯双键的比例为100∶63∶32∶40∶32 (49.3∶31.0∶16.0∶19.9∶16.0) 相似文献
13.
Bo Liu Shan Liu Ling-Yan Meng Ya-Yu Li Bin Wang Ming-Guo Ma 《Journal of Saudi Chemical Society》2018,22(5):509-518
Biomass charcoal-doped titanium dioxide (C/TiO2) composites were proposed by microwave-hydrothermal and calcination method using tetrabutyl titanate as the titanium source and lignin as the carbon source. TiO2 crystals with different morphologies could be successfully adsorbed onto the surface of biomass charcoal. These products were investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TG), derivative thermogravimetric (DTG), UV–vis diffuser flection spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FT-IR), and Brunauer–Emmett–Teller (BET). The photocatalytic activities of the as-obtained composites were checked under visible light irradiation. The results showed that both the microwave-hydrothermal temperature and time played an important role in the microstructure and photocatalytic activity of the samples. The rapid microwave-hydrothermal with the thermal post-treatment provides a promising route for the fabrication of biomass charcoal-doped nanocomposites materials. 相似文献
14.
F. Burstein M. Borisover I. Lapides S. Yariv 《Journal of Thermal Analysis and Calorimetry》2008,92(1):35-42
In the present research we studied the effect of the solvent used, whether it was polar water or a non-polar organic solvent
(n-hexane or n-hexadecane), on the basal-spacing and bulk structure of the sorbate-sorbent complexes obtained by the secondary adsorption
of nitrobenzene and m-nitrophenol by two types of organo-montmorillonites. X-ray measured basal spacings before and after thermal treatments up
to 360°C. The organo-clays were synthesized, with 41 and 90% replacement of the exchangeable Na+ by hexadecyltrimethylammonium (HDTMA), with mono-and bilayers of HDTMA cations in the interlayer space, labelled OC-41 and
OC-90, respectively. After heating at 360°C both organo-clays showed spacing at 1.25–1.28 nm, due to the presence of interlayer-charcoal,
indicating that in the preheated organo-clays the HDTMA was located in the interlayer.
The thermo-XRD-analysis of Na-clay complexes showed that from organic solvents both sorbates were adsorbed on the external
surface but from water they were intercalated. m-Nitrophenol complexes of both organo-clays obtained in aqueous suspensions contain water molecules. Spacings of nitrobenzene
complexes of OC-41 and OC-90 and those of nitrophenol complexes of OC-41 showed that the adsorbed molecules were imbedded
in cavities in the HDTMA layers. Adsorption of m-nitrophenol by OC-90 from water and n-hexane resulted in an increase of basal spacing (0.21 and 0.29 nm, respectively) suggesting the existence of a layer of nitrophenol
molecules sandwiched between two parallel HDTMA layers. 相似文献
15.
The versatility of palladium(II) acetate and palladium on activated charcoal catalysts with triethylsilane has been investigated in the hydrogenation and the isomerization of carbon–carbon double bond of 1‐alkenes. The reduction of 1‐alkenes was carried out in the presence of triethylsilane, ethanol and a catalytic amount of palladium(II) acetate or palladium on activated charcoal, at room temperature. This facile and efficient method affords high yields for hydrogenation of unsaturated alkenes to the corresponding alkanes. Then the carbon–carbon double bond isomerization of 1‐alkenes was tested using the same catalysts in the absence of solvent. The system palladium(II) acetate‐triethylsilane was found to be more effective compared with palladium on an activated charcoal–triethylsilane system at room temperature, while comparable results were obtained at 50 °C for both catalysts. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
16.
描述了一种单向连续竹纤维增强聚合物试件的制作工艺过程:研究了该型竹纤维增强复合材料的拉伸力学性能。将该性能与单向连续玻璃纤维增强聚合物的拉伸力学性能进行了比较,发现竹纤维增强聚合物的拉伸模量要明显高于玻璃纤维增强聚合物的对应值,而其拉伸强度和玻璃纤维增强聚合物的相当。同时发现竹纤维增强聚合物的纵向延展性较小,呈现一次性单界面脆性断裂状况,相对地,连续玻璃纤维增强聚合物的拉伸断裂是多次多界面分段断裂。 相似文献
17.
18.
Bin Yang Chen-Wu Liang Fei-Xue Lu Qin-Ting Chen Jin Chen 《Journal of Macromolecular Science: Physics》2019,58(2):341-354
The effects of bamboo flour (BF) content on the dynamic rheological properties of BF-filled HDPE composites were investigated. Our findings showed that the addition of BF caused an enhancement of the non-Newtonianism of wood-plastic composites (WPCs) melt as well as the appearance of some new relaxation processes. In addition, the viscosity and modulus of the BF-filled HDPE composites showed a remarkable increase at 170?°C and 190?°C when the BF content exceeded 30%, which could be associated with the solid-like property of the WPCs at high BF loading, we propose. The present study we suggest will be useful to the formula design as well as the optimization of processing parameters for WPCs in general. 相似文献
19.
《Surface and interface analysis : SIA》2018,50(2):234-239
This paper is concerned with the effects of the air plasma surface treatment of bamboo fiber on the tribological properties of the bamboo fiber reinforced polyimide (bamboo/polyimide) composites filled with graphite. Plasma treatment and graphite bring positive effect on the improvement of friction reducing and antiwear of bamboo/polyimide composites. And Fourier transform infrared spectroscopy analysis shows that the bamboo fibers have been oxidized and etched by the air plasma treatment. The presence of active groups makes the polarity of the fiber increase, and so the bond property between the fiber and matrix is improved. 相似文献
20.
D. A. Bykov A. N. Zaderko A. M. Datsyuk V. E. Diyuk V. K. Yatsimirskii V. V. Lobanov 《Theoretical and Experimental Chemistry》2008,44(1):32-36
LCAO MO SCF calculations using the 3-21G basis were used to study the electronic and three-dimensional structure of several
polycyclic aromatic hydrocarbons as models for the surface of activated charcoal. Localized carbon-carbon double bonds capable
of adding electrophilic reagents were found on the periphery of these molecules. The reactivity of the peripheral C=C bonds
was evaluated relative to consecutive bromination reactions of the C54H18 molecule.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 44, No. 1, pp. 30–34, January–February, 2008. 相似文献