We present the design and performance of the High Dispersion Spectrograph (HDS) of the Subaru Telescope. HDS is an echelle spectrograph located at the Nasmyth focus of the telescope. The collimated beam size is 272 mm, and the echelle is 300 mm by 840 mm in total size ($31.6 \,\mathrm{gr} \,\mathrm{mm}^{-1}, R=2.8$). HDS has two cross-dispersing gratings with $400 \,\mathrm{gr} \,\mathrm{mm}^{-1}$ and $250 \,\mathrm{gr} \,\mathrm{mm}^{-1}$, which are optimized for the blue and red wavelength regions, respectively. The camera is of the catadioptric type system, consisting of three corrector lenses and a mirror. Two EEV-CCD’s with $4100 \times 2048$ pixels and a pixel size of 13.5 ${\mu \mathrm {m}}$ are used as the detector. A standard configuration with a ${0\rlap {.}{}^{\mathrm {\prime \prime }}4}$ slit gives a spectral resolution of $R=90000$, and a narrower slit width enables higher resolution of up to $R \sim 160000$. The spectrograph has sensitivities from 3000 ${Å}$ to 1 ${\mu \mathrm {m}}$, and one exposure covers a range of 1500–2500 ${Å}$, depending on the wavelength region. The throughput of the telescope and the spectrograph, including the efficiency of the detector, is about 13% in 5000–6000 ${Å}$ and about 8% at 4000 ${Å}$. The stability of the spectrograph and scattered light level are also reported.
Novel soft materials should comprise multiple supramolecular nanostructures whose responses (for example, assembly and disassembly) to external stimuli can be controlled independently. Such multicomponent systems are present in living cells and control the formation and break-up of a variety of supramolecular assemblies made of proteins, lipids, DNA and RNA in response to external stimuli; however, artificial counterparts are challenging to make. Here, we present a hybrid hydrogel consisting of a self-sorting double network of nanofibres in which each network responds to an applied external stimulus independent of the other. The hydrogel can be made to change its mechanical properties and rates of release of encapsulated proteins by adding NaSO or bacterial alkaline phosphatase. Notably, the properties of the gel depend on the order in which the external stimuli are applied. Multicomponent hydrogels comprising orthogonal stimulus-responsive supramolecular assemblies would be suitable for designing novel adaptive materials.
An overview of the current status of the 8.2 m Subaru Telescope constructed and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of Japan is presented. The basic design concept and the verified performance of the telescope system are described. Also given are the status of the instrument package offered to the astronomical community, the status of operation, and some of the future plans. The status of the telescope reported in a number of SPIE papers as of the summer of 2002 are incorporated with some updates included as of 2004 February. However, readers are encouraged to check the most updated status of the telescope through the home page, http://subarutelescope.org/index.html, and/or the direct contact with the observatory staff.
Self-assembly is promising for construction of a wide variety of supramolecular assemblies, whose 1D/2D/3D structures are typically relevant to their functions. In-depth understanding of their structure–function relationships is essential for rational design and development of functional molecular assemblies. Microscopic imaging has been used as a powerful tool to elucidate structures of individual molecular assemblies with subnanometer to millimeter resolution, which is complementary to conventional spectroscopic techniques that provide the ensemble structural information. In this review, we highlight the representative examples of visualization of molecular assemblies by use of electron microscopy, atomic force microscopy, confocal microscopy, and super-resolution microscopy. This review comprehensively describes imaging of supramolecular nanofibers/gels, micelles/vesicles, coacervate droplets, polymer assemblies, and protein/DNA assemblies. Advanced imaging techniques that can address key challenges, like evaluation of dynamics of molecular assemblies, multicomponent self-assembly, and self-assembly/disassembly in complex cellular milieu, are also discussed. We believe this review would provide guidelines for deeper structural analyses of molecular assemblies to develop the next-generation materials.
This paper describes the first light and subsequent test observations with the 8.2 m aperture Subaru Telescope constructed at the summit of Mauna Kea. Following the engineering first light, which started 1998 December, the astronomical first light and test observations were carried out in 1999 January with 4 testing instruments under seeing conditions of 0″.2*#x2013;0″.5 for near-infrared and 0″.3–0″.6 for optical wavelengths. The actively supported primary mirror was shown to achieve an overall imaging performance of 0″.1 (FWHM) or better in the absence of any atmospheric disturbance. The pointing accuracy of the telescope is about 1″ rms, and a closed-loop tracking accuracy of ≲ 0″.07 rms has been achieved. Infrared images of the Orion Nebula covering 5′ × 5′, obtained with J, K″, and H2v = 1–0 S(1) filters, have revealed much finer and fainter details of the BN/KL region, the bright bar, and other conspicuous features compared with previous observations. K′ band photometry of 516 point sources yielded a luminosity function with a peak at K′ ∼ 12 mag with a long tail in K′ ∼ 13 mag down to K″ ∼ 17 mag, suggesting a fairly large number of young brown dwarfs existing in the Trapezium cluster. Several new features around the Orion BN/KL region are also reported.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.