Abstract This paper is addressed to the laboratory spectroscopist who, although knowledgeable about spectrometers, is unfamiliar with solar research, especially that performed in space. G. K. Oertel has been a full-time science administrator for the past 5 years. He has participated in the Federal Executive Development Program since March 1974 and was first assigned to the Science and Technology Policy Office at the National Science Foundation. His outlook and approach to this review reflect these experiences in that he found it easier to survey the many facets of the field in general rather than in depth. G.K.O. has had the advantage of learning not just the conclusions, but also the thinking and plans of outstanding researchers in solar physics. In this regard he has had to balance his desire to give a timely picture against the need to protect ideas and developments that might not yet have received proper credit. 相似文献
The effect of the addition of NIR (near infrared reflective pigment filler, nickel antimony titanium yellow rutile) into the polyamide/metallocene-based polyethylene elastomer (mPE) blends on increasing the infrared reflection of PA6 (Polyamide 6) and limiting the thermal heat accumulation in light of environmental and energy conservation concerns was examined. The NIR was included in mPE or mPE-g-MA (maleic anhydride) to form NmPE or NmPE-g-MA masterbatches, respectively, which were used in combination with polyamide 6 (PA6) to prepare PA6/NmPE or PA6/NmPE-g-MA composites. The dispersed domains of mPE modifier were larger in dimension in comparison with those of the corresponding counterparts using mPE-g-MA as the NIR carrier due to the increased interfacial interactions of the anhydride groups of the MA and the amine groups in PA6. NIR tended to increase the crystallization temperature of PA6 of up to 3°C through the nucleation role of the NIR for the NmPE-filled samples. However, this increment was diminished at higher mPE-g-MA content for the NmPE-g-MA-filled samples, suggested to be due to the interaction of mPE-g-MA and PA6 impeding the chain mobility for crystallization growth, offsetting the nucleation role of NIR. The NmPE-g-MA modified samples resulted in the highest improvement in Young’s modulus compared with the NmPE modified samples. An increase of 2 times in the impact strength occurred for PA6/NmPE(60 phr) sample, which increased to a value of 80?±?5 (J/m). However, a non-break behavior was observed for the PA6/NmPE-g-MA samples at higher modifier contents. The values of infrared reflection increased significantly, indicating the effectiveness of NIR to improve the reflection properties of the prepared composite systems. 相似文献
Nanofabricated metallic tips are at the core of important research in single‐molecule imaging, near‐field scanning optical microscopy, tip‐enhanced Raman spectroscopy, as well as potential commercial applications such as heat‐assisted magnetic recording. While challenging to fabricate, much progress has been made towards the reliable production of extremely sharp (10 nm) metallic probes. In this review, the various factors that go into the design of metallic tips, their fabrication, packaging and system integration, characterization, passivation, and eventual use are discussed. Fabrication challenges, implementation issues, optical excitation schemes, and various current and emerging applications are also discussed. For the rapidly emerging fields of plasmonics and nanophotonics, the use of sharp metallic tips has generated significant scientific progress and will play an integral role well into the future. 相似文献
Recently, a large number of experimental and theoretical works have revealed a variety of plasmonic nanostructures with the capabilities of Fano resonance (FR) generation. Among these structures, plasmonic oligomers consisting of packed metallic nanoelements with certain configurations have been of significant interest. Oligomers can exhibit FR independently of the polarization direction based on dipole–dipole antiparallel modes without the need to excite challenging high‐order modes. The purpose of this review article is to provide an overview of recent achievements on FR of plasmonic nanostructures in recent years. Meanwhile, more attention is given to the optical properties of plasmonic oligomers due to the high potential of such structures in optical spectra engineering. 相似文献
Previous studies have shown that albumin has a high affinity towards tumours, and, as a result, many drug/albumin conjugates, as well as albumin nanoparticles, have been studied as antineoplastic drug carriers. Numerous studies have also shown the high affinity of cyanine dyes for albumin. This work combines the former and the latter for the preparation of NIR fluorescent and photostable nanoparticles as diagnostic biomaterials. Tumour‐specific labelling by NIR fluorescent polystyrene/albumin core/shell nanoparticles is demonstrated, without the presence of additional targeting moieties, and they possess great potential for clinical applications.
Fluorescence anisotropy in the near‐infrared (NIR) spectral range is challenging because of the lack of appropriate NIR fluorescent labels. We have evaluated polymethine fluorescent dyes to identify a leading candidate for NIR anisotropy applications. The NIR dye LS601 demonstrated low fluorescence anisotropy values (r) as a result of its relatively long fluorescent lifetime 1.3 ns. The r value of LS601 unbound and coupled to biological macromolecules was found to have a sufficient dynamic range from 0.24 to 0.37, demonstrating the feasibility of fluorescence anisotropy in the NIR. The viability of fluorescence anisotropy using a NIR label was demonstrated by characterization of dye–protein conjugates. These results open the door to a number of applications in drug discovery, fluorescence anisotropy imaging and contrast agent development. 相似文献