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991.
There is currently great interest in the potential use of carbon nanotubes as delivery vessels for nanotherapeutics and other
medical applications. However, no data are available on the effects of sterilization methods on the properties of nanotube
dispersions, the form in which most medical applications will be processed. Here we show the effects of gamma irradiation
from a 60Co source on the dispersion and optical properties of single-wall carbon nanotubes in aqueous dispersion. Samples of different
length-refined populations were sealed in ampoules and exposed to a dose of approximately 28 kGy, a level sufficient to ensure
sterility of the dispersions. In contrast to literature results for solid-phase nanotube samples, the effects of gamma irradiation
on the dispersion and optical properties of the nanotube samples were found to be minimal. Based on these results, gamma irradiation
appears sufficiently non-destructive to be industrially useful for the sterilization of nanotube dispersions. 相似文献
992.
Binder-free activated carbon/carbon nanotube paper electrodes for use in supercapacitors 总被引:1,自引:0,他引:1
Guanghui Xu Chao Zheng Qiang Zhang Jiaqi Huang Mengqiang Zhao Jingqi Nie Xianghua Wang Fei Wei 《Nano Research》2011,4(9):870-881
Novel inexpensive, light, flexible, and even rollup or wearable devices are required for multi-functional portable electronics
and developing new versatile and flexible electrode materials as alternatives to the materials used in contemporary batteries
and supercapacitors is a key challenge. Here, binder-free activated carbon (AC)/carbon nanotube (CNT) paper electrodes for
use in advanced supercapacitors have been fabricated based on low-cost, industrial-grade aligned CNTs. By a two-step shearing
strategy, aligned CNTs were dispersed into individual long CNTs, and then 90 wt%–99 wt% of AC powder was incorporated into
the CNT pulp and the AC/CNT paper electrode was fabricated by deposition on a filter. The specific capacity, rate performance,
and power density of the AC/CNT paper electrode were better than the corresponding values for an AC/acetylene black electrode.
The capacity reached a maximum value of 267.6 F/g with a CNT loading of 5 wt%, and the energy density and power density were
22.5 W·h/kg and 7.3 kW/kg at a high current density of 20 A/g. The AC/CNT paper electrode also showed a good cycle performance,
with 97.5% of the original capacity retained after 5000 cycles at a scan rate of 200 mV/s. This method affords not only a
promising paper-like nanocomposite for use in low-cost and flexible supercapacitors, but also a general way of fabricating
multi-functional paper-like CNT-based nanocomposites for use in devices such as flexible lithium ion batteries and solar cells.
相似文献
993.
采用溶液浸润AAO模板法,将自制的荧光稀土配合物Eu(aspirin)3 Phen掺杂到聚氯乙烯(PVC)溶液中,制备了有荧光特性的一维复合纳米线阵列。并采用扫描电镜(SEM)、能谱分析(EDS)及透射电镜(TEM)进行了结构分析,结果表明:掺杂稀土铕配合物的聚氯乙烯制备了规整的纳米线阵列,铕配合物存在于纳米线阵列中。此外,荧光发射光谱研究表明,复合纳米线阵列具有优并的发光性能,归因于稀土配合物在纳米阵列中能更好地分散。 相似文献
994.
995.
Niu JJ Schrlau MG Friedman G Gogotsi Y 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(4):540-545
Gold nanoparticle-decorated carbon nanotubes (CNTs) are used to study intracellular environments in situ using surface-enhanced Raman spectroscopy (SERS). CNTs are decorated with gold nanoparticles and assembled onto the tips of pulled glass capillaries to form a SERS-enabled endoscope. The sub-micrometer size and high mechanical strength of the endoscope make it possible to penetrate the cell membrane for intracellular probing and remain positioned inside during lengthy SERS measurements without causing damage to the cell. Using the SERS-enabled endoscope, DNA and other biomolecules are detected in situ within the nucleus of a single human cervical carcinoma cell in a minimally invasive manner. The SERS-enabled endoscopes exhibit high selectivity and sensitivity for detecting trace amounts of analytes (≈1 pM) in biofluid environments, highlighting their capabilities as label-free, biological sensors for real-time in situ cellular diagnostics, biological detection, and pharmaceutical research. 相似文献
996.
997.
998.
Carbon nanofibers (CNFs) and carbon nanotubes (CNTs) are new carbon-based materials. However, the production of CNFs and CNTs is very difficult due to the complicated processes and high temperature involved. Therefore, a method of fabrication is required that enables high throughput at a low cost.Our previous study reported that oxygen ion beam energy of 500 eV applied to glassy carbon (GC) forms the finest pitch conical anti-reflection (AR) structures, and that an irradiation time of more than 24 min fabricates conical AR structures with heights of more than 250 nm. After the fabrication of the AR structures, irradiation by an argon ion (Ar+ beam changes the surface morphology, and oblique angle irradiation can form CNFs. Thus, we carried out oblique Ar+ beam irradiation on conical carbon protrusions on GC fabricated by oxygen ion beam irradiation. As a result, CNFs have been formed using oxygen and argon ion beam irradiation at room temperature. In addition, multi-wall CNT can be obtained by two-step ion beam irradiation. 相似文献
999.
An implementation of adaptive null steering beamformer for flexible broad null control, based on constrained recursive updating of array response zeros and spatial FIR filters, is presented. The design allows the beamformer to form broad nulls and control their widths readily. The new method is of great advantage for sensor array in which the number of array elements is very large compared with the number of interferences the array is designed to suppress. The new beamformer is useful and effective in the environment where both stationary and moving interference signals exist since it can steer both sharp and controlled broad nulls in the appropriate directions. When compared with the conventional LMS covariance matrix taper (CMT) based broad null synthesis method, the proposed beamformer has a faster convergence rate; and compared with the QR-RLS CMT based broad null synthesis method, the proposed method has a lower complexity. 相似文献
1000.
在电子显微镜中对纳米材料和纳米结构进行原位测量是了解纳米材料的结构与性能关系的最重要手段,并且,在电子显微镜中操纵和加工纳米材料与纳米结构还可研究新结构和新器件.由于扫描电镜有大的样品室、可较容易地引入多个多种测量和操纵探针、并可配备多种探测器从多个角度对同一个样品进行表征,使得扫描电镜中的原位研究在纳米材料和纳米器件... 相似文献