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61.
Shao Su Xinpan Wei Yuanyuan Guo Yiling Zhong Yuanyuan Su Qing Huang Chunhai Fan Yao He 《Particle & Particle Systems Characterization》2013,30(4):326-331
A new kind of silicon nanowire (SiNWs)‐based nanoelectrode assembly, a gold‐nanoparticle‐decorated silicon nanowire array (AuNPs@SiNWsAr), is employed for the construction of high‐performance electrochemical sensors. Significantly, the electrochemical nanosensors are capable of sensitive detection of various electroactive molecules (e.g., dopamine (DA), ascorbic acid (AA), hydrogen peroxide (H2O2), and glucose). Further, DA molecules loaded on the surface of AuNPs@SiNWsAr preserve stable high electroactivity overnight without special protection, while free DA molecules may lose their biological activity due to severe oxidization in ambient environment. These findings may offer new opportunities for the design of high‐performance electrochemical nanosensors with high sensitivity and robust stability. 相似文献
62.
A. M. El-Agramy B. A. Henaish A. A. Shabaka 《Isotopes in environmental and health studies》2013,49(10):479-482
Radiophotolumenescence (RPL) of irradiated and non irradiated thin films of polymethylmethacrylate (PMMA) doped with anthracene (Anth) as a donor, and tetracyanoquinodimethane (TCNQ) as an acceptor, has been investigated. The RPL – glow spectrum was recorded to study the characterizing emission bands from the point of view of glow peak position and intensity and hence the prospective relative sensitivities. RFL – signal fading after one month storage in dark at room temperature post gamma irradiation was also studied. PMMA doped with 6:4 donor to acceptor ratio has been proved to be the most sensitive one with less fading regarding gamma detection. On the other hand 2 Anth: 8 TCNQ was found to be the proper dopant concentration ratio for thermal neutron detection. 相似文献
63.
Die Feinverteilung des Kalkes im Kalk-Quarzsand-Gemisch ist eine notwendige Bedingung fur hohe erreichbare Festigkeit der Silikatbaustoffe. Vergleiehende Untersuchungen über die Kalkverteilung an neutronenaktivierten feinkörnigen Baustoffproben mit Hilfe von Szintillationsmessungen des 47Ca-Gehaltes und mittels autoradiographischer Darstellung der Kalkverteilung in kleinen Prüfkörpern unter Ausnützung der relativ weichen β-Strahlung des 45Ca ergaben, daβ die autoradiographischen Aussagen über die Homogenität der Proben am besten mit den Festigkeitsiwerten der Prüfkörper korrespondieren. 相似文献
64.
The development of technology of new semiconductor devices requires fundamental studies of a number of phenomena taking place in semiconductors during the doping process or accompanying the doping process. These studies are concerned with the following problems: 1. Diffusion of gold in silicon and the effect of diffusion layers (particularly phosphorus layers) and epitaxial silicon layers on the distribution of gold in thin silicon plates. 2. Distribution of admixtures in silicon introduced with the aid of the ion implantation technique. Our studies concerned with the second of the above mentioned problems comprised an autoradiographic examination of the homogeneity of the beam of phosphorus ions implanted in silicon, and a study of some apparatus factors and of the purity of the basic material on the implantation. 相似文献
65.
66.
K. Irmer 《Isotopes in environmental and health studies》2013,49(10):417-418
Bei der kontinuierlichen Durchstrahlungsprüfung von Werkstücken werden überwiegend Meßeinrichtungen, bestehend aus 60Co-Strahlungsquelle, Szintillationsdetektor und schreibendem Meßgerät, verwendet 1. 相似文献
67.
We present an integrated algorithm on a Eulerian grid, for multimaterial simulations of energetic and inert materials modelled by non-ideal equations of state. We employ high-resolution shock capturing numerical algorithms for each material inside its domain and use an overlap domain method across the interface, maintained by a recently developed, hybrid, level-set algorithm. For applications to condensed explosives we implement a non-ideal, wide-ranging equation of state and reaction rate law. For inert materials, like plastic, metal, water, etc., we implement a (linear in the pressure) Mie–Grüneisen, (U p ?U s ), equation of state. We present a series of verifications of the integrated multimaterial code and show validations against experiment. We show examples of simulations of various experiments associated with real or planned experiments, some of which contain energetic materials (specifically the condensed explosives PBX-9502 and PBX-9501). 相似文献
68.
We report the inverse Meyer–Neldel (MN) rule in the thermally activated crystallization of a hybrid composite of phenol formaldehyde using two experimental approaches. In the first experiment, the annealing time dependence of the pre-exponential factor K 0 and the activation energy of crystallization E c were studied. In the second experiment, the annealing temperature dependence of the same parameters was investigated. We observed the inverse Meyer–Neldel rule between the pre-exponential factor K 0 and the activation energy of crystallization E c in both cases. 相似文献
69.
The FePt system has important perspectives as high-temperature corrosion-resistant magnets. In the form of rapidly solidified melt-spun ribbons, FePt-based magnets may exhibit in certain cases a two-phase hard–soft magnetic behaviour. The present paper deals with a microstructural and magnetic study of FePtAgB alloys with increasing Ag content. The aim is to identify and confirm the effect of Ag addition in decreasing the temperature of the FePt disorder–order structural phase transformation. A detailed high-resolution transmission electron microscopy study is employed, and the alternative disposal of hard and soft regions within the two-phase microstructure is observed and interpreted with respect to the X-ray diffraction results. In the as-cast Ag-containing samples, it is shown that there is an optimum of the Ag content for which best magnetic properties are obtained. Ag addition creates a nonlinear behaviour of the coercive field and the ordering parameter, similar to the RKKY interaction-induced interlayer exchange coupling (IEC) observed in magnetic layers separated by non-magnetic spacer layers. Direct formation of the L10 phase from the as-cast state in the FePtAgB alloys is reported with magnetic parameters compatible to other exchange spring permanent nanomagnets. These findings open novel perspectives into utilization of such alloys in applications requiring magnets operating in high-temperature industrial environments. 相似文献
70.
Thomas Hellweg 《Journal of polymer science. Part A, Polymer chemistry》2013,51(14):1073-1083
Core–shell microgels are of increasing interest as smart carriers of catalysts, as sensors, or as building blocks for colloidal superstructures. In the context of colloidal assemblies, photonic applications are probably the most promising ones. This progress report presents and discusses the most recent results in this area focusing on the last 2–3 years, and also gives some background information. In addition, potential perspectives of this area will be outlined. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1073–1083 相似文献