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1.
利用简易、绿色、一锅煮的水热法合成了花状氧化锌/银复合纳米材料。然后利用各种光谱和显微技术对复合物进行了表征,并讨论了其表面增强拉曼(SERS)性能和光催化性能。结果表明氢氧化钠的量对于这种复合纳米材料的形貌和性能具有重要的调节作用。和其他形貌的氧化锌/银复合纳米材料相比较,花状氧化锌/银复合纳米材料具有最佳的光催化性能。同时进一步以花状氧化锌/银复合纳米材料作为SERS基底研究其表面增强拉曼性能,结果表明这种复合材料同时具有很好的表面增强拉曼性能。光催化和表面增强拉曼结果表明这种花状氧化锌/银复合纳米材料有望在有机物检测中作为一种具有很好的可循环性的新表面增强拉曼基底材料。  相似文献   

2.
利用简易、绿色、一锅煮的水热法合成了花状氧化锌/银复合纳米材料。然后利用各种光谱和显微技术对复合物进行了表征,并讨论了其表面增强拉曼(SERS)性能和光催化性能。结果表明氢氧化钠的量对于这种复合纳米材料的形貌和性能具有重要的调节作用。和其他形貌的氧化锌/银复合纳米材料相比较,花状氧化锌/银复合纳米材料具有最佳的光催化性能。同时进一步以花状氧化锌/银复合纳米材料作为SERS基底研究其表面增强拉曼性能,结果表明这种复合材料同时具有很好的表面增强拉曼性能。光催化和表面增强拉曼结果表明这种花状氧化锌/银复合纳米材料有望在有机物检测中作为一种具有很好的可循环性的新表面增强拉曼基底材料。  相似文献   

3.
利用简易、绿色、一锅煮的水热法合成了花状氧化锌/银复合纳米材料。然后利用各种光谱和显微技术对复合物进行了表征,并讨论了其表面增强拉曼(SERS)性能和光催化性能。结果表明氢氧化钠的量对于这种复合纳米材料的形貌和性能具有重要的调节作用。和其他形貌的氧化锌/银复合纳米材料相比较,花状氧化锌/银复合纳米材料具有最佳的光催化性能。同时进一步以花状氧化锌/银复合纳米材料作为SERS基底研究其表面增强拉曼性能,结果表明这种复合材料同时具有很好的表面增强拉曼性能。光催化和表面增强拉曼结果表明这种花状氧化锌/银复合纳米材料有望在有机物检测中作为一种具有很好的可循环性的新表面增强拉曼基底材料。  相似文献   

4.
纳米氧化锌的固相合成及其气敏特性   总被引:28,自引:0,他引:28  
以酒石酸和乙二胺四乙酸为原料,分别与醋酸锌进行固相反应制得前驱化合物,进而热分解得到气敏材料氧化锌。用X射线粉末衍射和透射电镜对材料的陶瓷微结构进行了表征,并用静态配气法测试了材料在不同工作温度下对乙醇、氨气、液化石油气的灵敏度高,实验结果表明:用这种方法合成的氧化锌具有粒径小,工作温度低及对乙醇气体灵敏度高的特点。  相似文献   

5.
以介孔氧化硅薄膜为模板电沉积合成新型纳米结构   总被引:6,自引:0,他引:6  
施奇惠  杨海峰  程岩  闫妍  陈颖  屠波  赵东元 《化学学报》2004,62(20):2021-2024,F007
首次以不同孔道结构的介孔氧化硅薄膜为模板,采用电化学沉积的方法,合成了金属铜和半导体氧化锌的纳米材料,并对其结构进行了表征.以六方孔道结构的介孔氧化硅模板获得了直径为7nm的金属铜纳米线阵列;以笼状体心立方孔道结构的模板获得了具有哑铃状形貌的铜单质纳米颗粒.对于氧化锌纳米结构,电化学沉积过程使得氧化锌完全填充氧化硅模板的孔道,分别得到了具有六方和体心立方介孔结构的Zn0/SiO2纳米复合物薄膜.  相似文献   

6.
糠醛缩4-氨基安替比林与Ln(Ⅲ)配合物的合成、表征和热分解反应动力学;Ln(Ⅲ)配合物;希夫碱;合成;表征;热分解反应动力学  相似文献   

7.
用于筛膜反应器的γ-MnO2纳米粉的合成   总被引:1,自引:1,他引:1  
醋酸锰与柠檬酸发生沉淀反应生成锰配合物,经热分解和酸处理手段最终制备出γ-MnO2纳米材料,用X射线衍射、差热/热重分析、透射电镜及原子力显微镜等手段对合成的样品进行了表征.同时考察了反应条件对反应速度、最终产品粒度的影响.结果表明,通过对反应条件的控制可以在一定程度上控制产品的粒度,得到了均粒度和超细粒度的γ-MnO2纳米材料.对于异丙醇和环己烷等氧化脱氢反应,γ-MnO2纳米筛膜反应器与传统的固定床反应器相比反应物的转化率提高了20%.  相似文献   

8.
用于筛膜反应器的γ-MnO2纳米粉的合成   总被引:6,自引:0,他引:6  
醋酸锰与柠檬酸发生沉淀反应生成锰配合物,经热分解和酸处理手段最终制备出γ MnO2纳米材料,用X射线衍射、差热/热重分析、透射电镜及原子力显微镜等手段对合成的样品进行了表征.同时考察了反应条件对反应速度、最终产品粒度的影响.结果表明,通过对反应条件的控制可以在一定程度上控制产品的粒度,得到了均粒度和超细粒度的γ MnO2纳米材料.对于异丙醇和环己烷等氧化脱氢反应,γ MnO2纳米筛膜反应器与传统的固定床反应器相比反应物的转化率提高了20%.  相似文献   

9.
用于筛膜反应器的γ-MnO_2纳米粉的合成   总被引:4,自引:0,他引:4  
醋酸锰与柠檬酸发生沉淀反应生成锰配合物,经热分解和酸处理手段最终制备出γ-MnO2纳米材料,用X射线衍射、差热/热重分析、透射电镜及原子力显微镜等手段对合成的样品进行了表征.同时考察了反应条件对反应速度、最终产品粒度的影响.结果表明,通过对反应条件的控制可以在一定程度上控制产品的粒度,得到了均粒度和超细粒度的γ-MnO2纳米材料.对于异丙醇和环己烷等氧化脱氢反应,γ-MnO2纳米筛膜反应器与传统的固定床反应器相比反应物的转化率提高了20%.  相似文献   

10.
纳米钛酸钡生成的热分解机理   总被引:5,自引:0,他引:5  
钛酸钡作为重要的铁电材料 ,多年来一直被研究者们所关注.传统方法制备钛酸钡大多采用固相法或草酸盐法得到微米级基料.随着纳米材料研究与应用的发展 ,溶胶 凝胶技术成为制备各种金属氧化物纳米材料的较普遍方法.溶胶 凝胶法制备纳米钛酸钡就是其中之一.该法一般采用钛的有机醇盐与钡盐反应生成溶胶 ,然后形成凝胶 ,再以凝胶为先体进行热处理制得纳米钛酸钡.虽然已有人对溶胶 凝胶技术制备纳米钛酸钡进行了研究 ,并对所得产物进行了表征[1,2],但尚无人对该方法中凝胶的热分解过程作详细的研究.因凝胶的热分解过程对钛酸钡纳…  相似文献   

11.
《Solid State Sciences》2003,5(4):553-558
In this paper mechanical alloying has been used successfully to produce nanocrystalline powders of hydroxyapatite (HA) using five different experimental procedures in a pure dry process. The milled HA were studied by X-ray powder diffraction, infrared and Raman scattering spectroscopy. For four different procedures, HA was obtained after a couple of hours of milling (in average 60 hours of milling, depending in the reaction procedure). This milling process, used to produce HA, presents the advantage that melting is not necessary and the powder obtained is nanocrystalline with crystallite size in the range of 22 nm to 39 nm.  相似文献   

12.
采用离子交换法, 用十六烷基三甲基溴化铵处理钙基蒙脱土(MMT), 使蒙脱土的层间距由1.49 nm扩大到2.21 nm, 制备了环氧树脂/ BADK/MMT纳米复合材料, 并用XRD等手段研究了有机蒙脱土在环氧树脂中的插层及剥离行为. 研究结果表明, 蒙脱土含量及环氧树脂与有机土的混合温度和时间均对固化后复合材料的剥离产生影响, 只有在特定条件下才能得到剥离型纳米复合材料.  相似文献   

13.
One titrimetric and two spectrophotometric procedures have been reported for the determination of albendazole and its tablets. Using titrimetry, the drug was titrated directly with Chloramine-T under acidic conditions using a Methyl Orange indicator. The spectrophotometric procedures involve treating the sample solution with a measured excess of Chloramine-T in an acid medium, followed by an estimation of unreacted Chloramine-T by reacting with a fixed amount of either Methyl Orange or Indigo Carmine dye solution and measuring the absorbance at 510 nm or 610 nm. The stoichiometric ratio, which forms the basis for the calculations in titrimetry as well as the range of the applicability, are reported. The Beer's law range and sensitivity values for spectrophotometric procedures are included. The methods were applied to the determination of albendazole in tablets with satisfactory results.  相似文献   

14.
The preparation of nanoengineered materials with controlled nanostructures, for example, with an anisotropic phase segregated structure or a regular periodicity rather than with a broad range of interparticle distances, has remained a synthetic challenge for intermetallics. Artificially structured materials, including multilayers, amorphous alloys, quasicrystals, metastable crystalline alloys, or granular metals, are mostly prepared using physical gas phase procedures. We report a novel, powerful solution-mediated approach for the formation of nanoparticular binary antimonides based on presynthesized antimony nanoparticles. The transition metal antimonides M-Sb (M = Co, Ni, Cu(2), Zn) were obtained with sizes ranging from 20 and 60 nm. Through careful control of the reaction conditions, single-phase nanoparticular antimonides were synthesized. The nanophases were investigated by powder X-ray diffraction and (high resolution) electron microscopy. The approach is based on activated metal nanoparticles as precursors for the synthesis of the intermetallic compounds. X-ray powder diffraction studies of reaction intermediates allowed monitoring of the reaction kinetics. The small particle size of the reactants ensures short diffusion paths, low activation barriers, and low reaction temperatures, thereby eliminating solid-solid diffusion as the rate-limiting step in conventional bulk-scale solid-state synthesis.  相似文献   

15.
模板法室温合成CdS纳米棒   总被引:3,自引:0,他引:3  
模板法室温合成CdS纳米棒;模板法;硫化镉;一维CdS纳米材料  相似文献   

16.
The structure of microcrystalline cellulose (MCC) made by mild acid hydrolysis from cotton linter, flax fibres and sulphite or kraft cooked wood pulp was studied and compared with the structure of the starting materials. Crystallinities and the length and the width of the cellulose crystallites were determined by wide-angle X-ray scattering and the packing and the cross-sectional shape of the microfibrils were determined by small-angle X-ray scattering. The morphological differences were studied by scanning electron microscopy. A model for the changes in microfibrillar structure between native materials, pulp and MCC samples was proposed. The results indicated that from softwood or hardwood pulp, flax cellulose and cotton linter MCC with very similar nanostructures were obtained with small changes in reaction conditions. The crystallinity of MCC samples was 54–65%. The width and the length of the cellulose crystallites increased when MCC was made. For example, between cotton and cotton MCC the width increased from 7.1 nm to 8.8 nm and the length increased from 17.7 nm to 30.4 nm. However, the longest crystallites were found in native spruce wood (35–36 nm).  相似文献   

17.
Chalcopyrite ternary CuInS2 semiconductor nanocrystals have been synthesized via a facile one-pot chemical approach by using oleylamine and oleic acid as solvents.The as-prepared CuInS2 nanocrystals have been characterized by instrumental analyses such as X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM)/high-resolution TEM(HRTEM),energy-dispersive X-ray spectroscopy(EDS),UV-vis absorption spectroscopy(UV-vis) and photoluminescence(PL) spectroscopy.The particle sizes of the CuInS2 nanocrystals could be tuned from 2 to 10 nm by simply varying reaction conditions.Oleylamine,which acted as both a reductant and an effective capping agent,plays an important role in the size-controlled synthesis of CuInS2 nanocrystals.Based on a series of comparative experiments under different reaction conditions,the probable formation mechanism of CuInS2 nanocrystals has been proposed.Furthermore,the UV-vis absorption and PL emission spectra of the chalcopyrite CuInS2 nanocrystals have been found to be adjustable in the range of 527-815 nm and 625-800 nm,respectively,indicating their potential application in photovoltaic devices.  相似文献   

18.
溶剂热法合成CdS纳米晶及其光学性质研究   总被引:1,自引:0,他引:1  
以硫脲和醋酸镉为原料,采用溶剂热法在不同的反应介质和温度下合成了CdS纳米晶,比较了单胺与双胺对合成CdS纳米晶形貌的影响。采用透射电镜(TEM)、X射线粉末衍射仪(XRD)和荧光分光光度计(PL)对合成的CdS纳米晶结构和光学性能进行表征。结果表明:反应温度和反应介质对其形貌有影响,在双胺的条件下,60℃时合成了纯相的六方相CdS纳米棒;双胺条件下更易生成纳米棒,且高温下晶体的结晶性更好。PL分析表明,水(溶剂)热法制备的CdS的荧光光谱图与大多数CdS类似,均在440~480 nm和550 nm处存在发射峰,但较宽的发射峰蓝移说明材料的光学性质受到材料形貌和制备方法的影响。  相似文献   

19.
The calcium silicate systems were prepared by sol–gel methods—varying the synthesis conditions (precursor solutions, chemical compositions, catalysts, temperature and time of aging and heat treatment). The precursors of sol–gel procedures were calcium nitrate and tetraetoxysilane. Acetic acid, water, ammonia and nitric acid were applied as catalysts. The atomic and supramolecular structures of calcium silicate products have been varied from amorphous to crystalline phases depending strongly on the preparation conditions. The structures were investigated in atomic range with Fourier transform infrared (FTIR), X-ray diffraction (XRD) and in supramolecular ranges with small angle X-ray scattering (SAXS), ultra small angel X-ray scattering (USAXS) measurements. The mechanical properties could be most efficiently improved by heat treatments (min. 600 °C) and a post-treatment with tetraetoxysilane (TEOS). The mechanical strength of bulk biomaterials has been controlled by Brinell hardness test.  相似文献   

20.
Montmorillonite(MMT) was directly modified with hexadecyl trimethyl ammonium bromide. The interlayer spacing of the organophilic montmorillonite(organo-MMT) corresponding to the d(001) plane peak was 2.21 nm. The influences of the content of organo-MMT and mixing conditions including mixing temperature and mixing time on the intercalation and exfoliation structures of MMT/epoxy resin composites were investigated by wide X-ray diffraction(WXRD). The X-ray patterns reveal that organo-MMT was intercalated by the epoxy resin during mixing process. Only under certain mixing conditions, could the exfoliation nanocomposites be formed. The mechanical and thermal properties of the composites were measured. The results indicate that the composites have better mechanical properties and higher Tg than those of the pristine epoxy resin.  相似文献   

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