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1.
由于具有较大的孔道尺寸、 丰富的化学组成以及广阔的应用前景, 大孔道介孔纳米材料近年来引起了科研工作者的广泛关注. 分别利用复合胶束和无机纳米晶作为结构基元进行可控自组装的软模板法和硬模板法是合成这类大孔道介孔纳米材料最有效的两类方法. 本文总结了一系列基于不同类型软模板或硬模板共组装形成大孔道介孔纳米材料的合成方法和策略, 并讨论了所获得的大孔道介孔纳米材料在催化、 能量转换与存储以及生物医学中的应用. 最后, 对利用新型嵌段聚合物或复杂结构纳米晶合成大孔道介孔纳米材料的前景和挑战进行了展望.  相似文献   

2.
采用电泳沉积法, 在FTO/介孔TiO2薄膜上制备了介孔TiO2/单壁碳纳米管(SWCNTs)薄膜电极, 用Raman和SEM等手段对薄膜电极进行了表征. 结果表明, SWCNTs已沉积到介孔TiO2薄膜上. 分别用四羧基苯基卟啉(TCPP)和联吡啶钌化合物N719对其进行敏化, 并组装成太阳能电池. 研究结果表明, 与单纯的TiO2粒子膜相比, 介孔TiO2和SWCNTs的紧密结合可使得光生电子更容易传输, 光电转换效率显著提高.  相似文献   

3.
阵列叉指式芯片研究细胞介电电泳富集过程   总被引:2,自引:0,他引:2  
采用阵列叉指电极介电电泳(Dielectrophoresis,DEP)芯片,构建了集成DEP芯片分析和操控系统,应用Coventorware有限元分析软件模拟分析了芯片表面的电场分布情况;以红细胞和结肠癌细胞样品为分析对象,实现了两种细胞样品在芯片上的正负介电电泳定位富集.实验发现,交流信号幅值Vp-p是决定DEP富集效率的主因,交流信号频率f和缓冲溶液是改变细胞介电电泳类型的参量;在0.9% NaCl中,施加频率为10和3 MHz、电压5 V的交流频率,结肠癌细胞的正介电电泳(Positive-dielectrophoresis, pDEP)和负介电电泳(Nagetive-dielectrophoresis, nDEP)富集效率分别为87.2%和84.8%.  相似文献   

4.
芯片介电电泳技术是以介电电泳(DEP)分离原理和微机电加工技术为依托发展起来的可用于生化样品分析的新型分析技术.本文概述了芯片介电电泳技术的发展和DEP芯片分析系统的构成,并以DEP操控模式为切入点,介绍了芯片介电电泳在生化样品分析中的应用情况.  相似文献   

5.
基于介电电泳的微流控细胞分离芯片的研究进展   总被引:2,自引:0,他引:2  
细胞分离技术是细胞分选和细胞种群纯化的重要手段,在生物、医学、农业、环境等许多领域都有重要的应用,是当前生化分析领域的国际研究热点。本文介绍了基于介电电泳的微流控细胞分离芯片的研究现状,阐述了介电电泳的工作原理,并依据细胞尺寸、电极形状、外加信号方式等影响细胞介电电泳的关键因素对不同类型的微流控细胞分离芯片进行了详细介绍,并对该技术的未来发展趋势做了展望。  相似文献   

6.
微流控芯片中微液滴的操控及其应用   总被引:3,自引:0,他引:3  
张凯  胡坪  梁琼麟  罗国安 《分析化学》2008,36(4):556-562
微流控芯片中微液滴的操控方法主要有多相流法、电润湿法、热毛细管法、介电电泳法和气动法;应用范围包括乳化、混合、包埋、萃取、微反应器以及生物鉴定等。论文展望了微液滴的发展前景。  相似文献   

7.
张晓东  董寒  王吟  崔立峰 《化学进展》2015,27(10):1374-1383
介孔分子筛材料具有高的比表面积和孔体积、发达的孔结构、可控的形貌、表面基团可功能化、耐热、无毒无害等特点,以其为研究核心,在学术界和工业界均具有广泛的应用前景。通过模板法合成孔径在纳米范围的有序介孔硅材料,其具有从一维到三维高度规整的孔道结构,在吸附、分离、催化、生物医药工程等领域展现出巨大的应用潜能。利用具有几何和电子束缚特性的有序规整孔道作为微反应器来进行纳米结构主-客体组装,势必会显著增强其应用价值。本文以有序介孔硅材料规整孔道为基础和出发点,结合本课题组多年的研究结果,系统概述了近几年客体在有序介孔硅材料孔道内组装的进展,探讨了主-客体组装过程中的影响因素和合成机理。最后,着重对主-客体组装材料在环境净化和生物医药工程领域的应用进行概述。  相似文献   

8.
介孔金属氧化物及其复合物由于其特有的组成与结构, 在催化、传感、光、电、磁等领域有着广泛的应用, 是近年来国内外跨学科领域研究的热点。本文对近几年来介孔金属氧化物及其复合物的合成方法进行了归纳总结, 其合成途径大致可以分为软模板法、硬模板法及纳米晶粒组装法。  相似文献   

9.
将电聚合和层层组装方法有效结合构筑了聚硫堇(PTH)电子介体修饰的碳纳米管(CNTs)/辣根过氧化物酶(HRP)多层膜无试剂H2O2传感器.利用电化学阻抗谱对CNTs/HRP多层膜的组装过程进行监测,用循环伏安法和计时电流法研究了该HRP电极的电化学行为.探讨了酶组装层数、工作电位、pH值和碳纳米管对电极响应的影响.该...  相似文献   

10.
在分离领域,纳米技术主要以两种形式改善分离效果,一种是利用金、二氧化硅、聚合物、金属氧化物和碳纳米管等纳米材料,二是通过微机电加工、化学方法或者自组装技术构筑纳米障碍物和纳通道等纳米结构。本文对两种不同形式的纳米技术在毛细管电泳和微流控芯片电泳生物分离中的应用进行了综述。并对该领域未来的发展进行了展望。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

19.
20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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