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纳米银负载的炭气凝胶制备及抗菌性能研究 总被引:3,自引:0,他引:3
以常压干燥法制备的酚醛有机气凝胶为原料,通过在硝酸银溶液中浸渍使银吸附或沉积在有机气凝胶上,在常压条件下干燥并炭化制得纳米银负载的炭气凝胶。利用扫描电镜(SEM)、透射电镜(TEM)、X-射线衍射(XRD),比表面积及孔径分析等方法研究了浸渍前后凝胶密度和结构的变化,以及制备条件对银负载炭气凝胶的载银量和凝胶结构的影响;研究了载银炭气凝胶对大肠埃氏杆菌(ATCC25922)和金黄色葡萄球菌(ATCC25923)的抗菌效果。结果表明,这类银负载炭气凝胶对大肠杆菌和金黄色葡萄球菌均有很强的杀灭能力,预期炭气凝胶在作为催化剂或吸附杀菌材料方面有良好的应用前景。 相似文献
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天然气吸附剂的开发及其储气性能的研究:Ⅰ.吸附剂制备与体积 … 总被引:16,自引:4,他引:12
报道了天然气吸附剂的基本制备技术,并采用体积法评定了吸附剂的储气性能。结果表明,采用作者开发的吸附剂制备工艺可获得性能优良的天然气吸附剂。以木质素为原料制备的粉状吸附剂,其比表面积可达2912m^2/g,微孔体积可达1.48cm^3/g,平均孔径为1.48nm,堆密度为0.30g/cm^3。在6.0MPa、25℃下,天然气的吸附储存量可达到140V/V。天然气吸附剂的储气性能与其比表面,微孔数量, 相似文献
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催化褪色光度法测定痕量钡 总被引:2,自引:0,他引:2
Ba^2+能在pH5弱酸性介质中催化十二烷基苯磺酸钠(DBS)对铬黑T(EBT0的褪色反应。详细研究了动力学条件,确立测定钡的最适宜催化动力学条件。表观摩尔吸光系数ε620=3.0×10^-6L.mol^-1cm^-1,校正曲线方程为logA0/A=0.006260+0.08704CBa^2+(μg/L);线性范围0-16μg/L(r=0.9991); 相似文献
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KBrO3—KBr紫外分光光度法测定痕量水杨酸 总被引:5,自引:0,他引:5
研究了HCl溶液中KBrO3-KBr紫外分光光度法测定水杨酸的条件,建立了测定痕量水杨酸的新方法。结果表明,在0.6mol/LHCl,3*10^-5mol/LKBrO3,5*10^-4mol/LKBr,6*10^-4mol/lKI溶中测定水杨酸,其线性范围为0.2-4.0mg/L,表观摩尔吸光系数为1.9*10^-4L.mol^-1.cm^-1,Sandell为7.3μg/cm^2。sg if e 相似文献
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K2CO3活化煤矸石制备活性炭吸附剂 总被引:5,自引:0,他引:5
用K2CO3化学活化煤矸石制备适用于废水处理的活性炭吸附剂.考察了活化条件对产物的比表面、孔体积及灰分的影响.增加了前处理和后处理步骤以改善产物的性能.最佳条件下获得的活性炭吸附剂BET比表面达1236m2/g,孔体积0.679cm3/g.所制得的吸附剂表面是疏水性的,对水溶液中的酚类污染物有良好的吸附性能. 相似文献
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NH3—PDS法焦炉气脱硫脱氰的模拟研究 总被引:2,自引:0,他引:2
本文介绍了以焦炉气中自有的NH3为碱源,在PDS的催化作用下,脱除煤气中H2S,HCN的工艺模拟研究,提出了新的焦炉气净化工流程,称为A-PDS工艺。选择出了适宜的工艺条件,可将煤气中H2S由5-7g/m^3脱至20mg/m^3以下,脱除率达99%以上;可将HCN由0.8-1.3g/m^3脱至20mg/m^3以下,脱除率达98%。 相似文献
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丁基罗丹明B—钼酸盐光度法连续测定铈和钪 总被引:4,自引:0,他引:4
在聚乙烯醇(PVA)存在下,丁基罗丹明B(BRB)分别与铈钼、钪钼杂多酸络阴离子形成离子缔合物,其最大吸收均位于570nm,表面摩尔吸光度分别为εCe=3.96×10^6L.mol^-1.cm^-1,εSc=4.71×10^5L.mol^-1.cm^-1,服从比耳定律范围分别为0-24μg/L Ce和0-60μg/LSc,测定极限为Ce1.0μg/L(n=12)和Sc1.9μg/L(n=10),对 相似文献
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Mn(Ⅲ)—苯甲酰丙酮缩乙二胺—有机碱配合物的合成及结构 总被引:1,自引:0,他引:1
合成了4种锰(Ⅲ)-苯甲酰丙酮缩乙二胺-有机碱配合物:Mn(bzacen)LClO4.(L为哌嗪,吡啶,γ-甲基吡啶和乙腈)。测定了配合物[Mn(bzacen)(CH3CN)ClO4]的结构,晶体属正交晶系。空间群Pnma。晶胞参数:a=0.9077(1),b=1.5563(1)nm,c=1.7205(2)nm,V=2.4305nm^3,Z=4,Dc=1.48g/cm^3,Dm=1.49g/cm^ 相似文献
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碳气凝胶的制备研究 总被引:3,自引:0,他引:3
气凝胶是由纳米量级超细粒子或高聚物分子聚结构成的多孔性轻质固态材料 ,它在声学、光学、电学、动力学和低温热学等方面具有独特性质 ,因此受到多方面研究者的重视 [1~ 4 ] .碳气凝胶最先是由 Pekala等 [5] 在 80年代末研制成功的 ,其突出特点是网络连续 ,电导率高 ,孔洞微小且相互贯通 ,比表面大 ,密度变化范围大 ,是制造高性能电容器和电池的新一代理想材料[6 ,7] .这种材料的低温电导率随温度连续单调变化 ,在一定温区范围内 ( <1 0 0 K)其电阻温度敏感度远大于传统的掺碳玻璃、锗以及其它金属电阻温度计材料 ,可望成为一种理想的低… 相似文献
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Si‐Cheng Li Bi‐Cheng Hu Dr. Yan‐Wei Ding Prof. Hai‐Wei Liang Chao Li Dr. Zi‐You Yu Dr. Zhen‐Yu Wu Prof. Wen‐Shuai Chen Prof. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2018,57(24):7085-7090
Carbon aerogels with 3D networks of interconnected nanometer‐sized particles exhibit fascinating physical properties and show great application potential. Efficient and sustainable methods are required to produce high‐performance carbon aerogels on a large scale to boost their practical applications. An economical and sustainable method is now developed for the synthesis of ultrathin carbon nanofiber (CNF) aerogels from the wood‐based nanofibrillated cellulose (NFC) aerogels via a catalytic pyrolysis process, which guarantees high carbon residual and well maintenance of the nanofibrous morphology during thermal decomposition of the NFC aerogels. The wood‐derived CNF aerogels exhibit excellent electrical conductivity, a large surface area, and potential as a binder‐free electrode material for supercapacitors. The results suggest great promise in developing new families of carbon aerogels based on the controlled pyrolysis of economical and sustainable nanostructured precursors. 相似文献
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制备出一系列不同结构的炭气凝胶和有机气凝胶。通过吸附实验,研究了其吸附茶碱的动力学行为。实验表明,炭气凝胶比有机气凝胶吸附速率快,吸附平衡时间短。炭气凝胶与文献报道的酚醛树脂对茶碱的吸附量相当,但吸附速率较快。茶碱在气凝胶上的吸附量随时间的变化规律遵从Langmuir方程,也符合假二级动力学吸附方程。 相似文献
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Resorcinol–formaldehyde aerogels (five samples, three of them with addition of nitrogen containing precursors—3-hydroxypyridine,
3-aminophenol and melamine) have been prepared by sol–gel polycondensation, subcritical drying and pyrolysis. The pyrolysis
of prepared organic aerogels has been studied by non-isothermal TG at constant heating rate. The process of pyrolysis has
been found to consist of three steps with the total mass loss 40.2–61.7% (room temperature—1,000 °C). The resulted carbon
aerogels have been tested as sorbents of Ni(II), Pb(II) and Cu(II) ions from aqueous solutions. Various relations have been
found among the results obtained from the pyrolysis experiments and properties affecting adsorption. Besides the expected
correlation between the mass loss gained from TG (isothermal step at 500 °C was applied) and from heating in the laboratory
oven, the relationship between the mass loss during pyrolysis and sorption capacities for all three metal ions has been found.
Other relations among pyrolysis behaviour, surface area and content of nitrogen have been also examined. Batch adsorption
experiments show (with an exception of one sample) that N-doped samples have higher adsorption capacity for metal ions. In
addition, changing of nitrogen functionalities during the pyrolysis has been considered and pyridinic-N (N-6) functionality
has been contemplated as a suitable structure for the adsorption process. 相似文献
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Metal–organic frameworks (MOFs) are promising alternative precursors for the fabrication of heteroatom‐doped carbon materials for energy storage and conversion. However, the direct pyrolysis of bulk MOFs usually gives microporous carbonaceous materials, which significantly hinder the mass transportation and the accessibility of active sites. Herein, N‐doped carbon aerogels with hierarchical micro‐, meso‐, and macropores were fabricated through one‐step pyrolysis of zeolitic imidazolate framework‐8/carboxymethylcellulose composite gel. Owing to the hierarchical porosity, high specific surface area, favorable conductivity, excellent thermal and chemical stability, the as‐prepared N‐doped carbon aerogel exhibits excellent oxygen reduction reaction (ORR) activity, long‐term durability, and good methanol tolerance in alkaline medium. This work thus provides a new way to fabricate new types of MOF‐derived carbon aerogels for various applications. 相似文献
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Ultralow-density nanostructured metal foams: combustion synthesis, morphology, and composition 总被引:1,自引:0,他引:1
Tappan BC Huynh MH Hiskey MA Chavez DE Luther EP Mang JT Son SF 《Journal of the American Chemical Society》2006,128(20):6589-6594
The synthesis of low-density, nanoporous materials has been an active area of study in chemistry and materials science dating back to the initial synthesis of aerogels. These materials, however, are most often limited to metal oxides, e.g., silica and alumina, and organic aerogels, e.g., resorcinol/formaldehyde, or carbon aerogels, produced from the pyrolysis of organic aerogels. The ability to form monolithic metallic nanocellular porous materials is difficult and sometimes elusive using conventional methodology. Here we report a relatively simple method to access unprecedented ultralow-density, nanostructured, monolithic, transition-metal foams, utilizing self-propagating combustion synthesis of novel transition-metal complexes containing high nitrogen energetic ligands. During the investigation of the decomposition behavior of the high-nitrogen transition metal complexes, it was discovered that nanostructured metal monolithic foams were formed in a post flame-front dynamic assembly having remarkably low densities down to 0.011 g cm(-3) and extremely high surface areas as high as 270 m(2) g(-1). We have produced monolithic nanoporous metal foams via this method of iron, cobalt, copper, and silver metals. We expect to be able to apply this to many other metals and to be able to tailor the resulting structure significantly. 相似文献
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Parkpoom Lorjai Thanyalak Chaisuwan Sujitra Wongkasemjit 《Journal of Sol-Gel Science and Technology》2009,52(1):56-64
New organic aerogels were successfully prepared from a new class of phenolic resins called polybenzoxazines synthesized via
conventional thermal curing reaction of a benzoxazine monomer using xylene as a solvent. Without the need for using supercritical
conditions to remove the solvent during the process, the carbon aerogels were obtained with a much shortened time. From two
different concentrations of benzoxazine solution, 20 and 40 wt%, the resulting polybenzoxazine aerogels, having densities
of 260 and 590 kg/m3, respectively, were obtained after the curing process. The subsequent carbon aerogels were prepared by the carbonization
of polybenzoxazine aerogels. The corresponding carbon aerogels exhibited a microporous structure with pore diameters less
than 2 nm, the densities of 300 and 830 kg/m3, and surface area of 384 and 391 m2/g, respectively. The texture of the carbon aerogels was denser than that of their organic aerogel precursor, as evidenced
by scanning electron microscopy. The transformation of the polybenzoxazine aerogel to the carbon aerogel was clearly observed
using fourier transform infrared spectroscopy. 相似文献
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《无机化学与普通化学杂志》2018,644(3):155-160
A series of carbon aerogels were synthesized by polycondensation of resorcinol and formaldehyde using cetyltrimethyl ammonium bromide (CTAB) as a catalyst. The structure and properties of carbon aerogels were characterized by X‐ray diffraction (XRD), Raman, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT‐IR), and N2 adsorption‐desorption technologies. Besides, the CO2 capture behavior of carbon aerogels was also investigated. It was found that the amount of CTAB affected the structure and morphology of carbon aerogels, thus influenced the CO2 adsorption behavior. The sample CA‐125 (the ratio of resorcinol and CTAB is 125) had the highest CO2 adsorption capacity (63.71 cm3 · g–1 at 1 bar and 24.14 cm3 · g–1 at 0.15 bar) at 25 °C. In addition, the higher CO2 adsorption capacity was ascribed to the higher surface area, pore volume and appropriate pore size, as well as the more defects over carbon aerogels. 相似文献