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Nanoscale imaging applications of soft X-ray microscope based on a gas-puff target source
Get PDFA compact microscope based on nitrogen double stream gas puff target soft X-ray source, which emits radiation in the water-window spectral range, at the wavelength of λ = 2.88 nm, is presented. The microscope, employing ellipsoidal grazing incidence condenser and a Fresnel zone plate objective, is capable of capturing images with a 60 nm spatial resolution and exposure time as low as a few seconds. Examples of different applications of the SXR microscopy, and its applicability for various fields of science, are presented and discussed
A desktop extreme ultraviolet microscope based on a compact laser-plasma light source
Get PDFA compact, desktop size microscope, based on laser-plasma source and equipped with reflective condenser and diffractive Fresnel zone plate objective, operating in the extreme ultraviolet (EUV) region at the wavelength of 13.8 nm, was developed. The microscope is capable of capturing magnified images of objects with 95-nm full-pitch spatial resolution (48 nm 25–75% KE) and exposure time as low as a few seconds, combining reasonable acquisition conditions with stand-alone desktop footprint. Such EUV microscope can be regarded as a complementary imaging tool to already existing, well-established ones. Details about the microscope, characterization, resolution estimation and real sample images are presented and discussed
Soft X-ray microscope with nanometer spatial resolution and its applications
No full textA compact size microscope based on nitrogen double stream gas puff target soft X-ray source, which emits radiation in water-window spectral range at the wavelength of λ = 2.88 nm is presented. The microscope employs ellipsoidal grazing incidence condenser mirror for sample illumination and silicon nitride Fresnel zone plate objective for object magnification and imaging. The microscope is capable of capturing water-window images of objects with 60 nm spatial resolution and exposure time as low as a few seconds. Details about the microscopy system as well as some examples of different applications from various fields of science, are presented and discussed
Characterization and optimization of images acquired by a compact soft X-ray microscope based on a double stream gas-puff target source
No full textUsing a table-top size soft X-ray (SXR) microscope, based on a laser plasma source with a double stream gas-puff target and a Fresnel zone plate objective, series of images of test samples were acquired. Characterization and optimization of the acquisition parameters were studied and evaluated in terms of signal to noise ratio (SNR). Conclusions for the optimization of SXR imaging were reached. Similar SNR measurements might be performed to characterize other SXR imaging systems as well. Software enabling live calculation of the SNR during the image acquisition might be introduced in future in the compact imaging systems for optimal image acquisition or for benchmarking purposes
Nanoimaging using soft X-ray and EUV sources based on double stream gas-puff targets
No full textIn this work we present recent results on nanoscale imaging in the extreme ultraviolet and soft X-ray spectral ranges, describing three novel imaging systems dedicated for high spatial resolution imaging of nanoscale objects with the extreme ultraviolet and soft X-ray radiations. The extreme ultraviolet and soft X-ray full field microscopes operate at 13.8 nm and 2.88 nm wavelengths and are capable of imaging of nanostructures with a sub-50 nm spatial resolution. A soft X-ray contact microscope operates in the “water-window” spectral range from 2.3 to 4.4 nm wavelength, to obtain images of an internal structure of the investigated object in a thin surface layer of soft X-ray light sensitive photoresist. The development of such compact imaging systems may, in the near future, be important from the point of view of new research related to biological, material science, and nanotechnology applications. Such preliminary applications are also shown in the studies of biological samples, including carcinoma cells, diatoms, and neurons
Biological and material science applications of EUV and SXR nanoscale imaging systems based on double stream gas puff target laser plasma sources
No full textIn the last 30 years much effort was made in order to develop compact laser-produced plasma sources emitting short wavelength radiation, from the soft X-ray (SXR, λ = 0.1–10 nm), especially in the so-called “water window” (λ = 2.3–4.4 nm) and in the extreme ultraviolet (EUV, λ = 10–120 nm) spectral ranges. Investigations in the nanometer scale, employing short wavelengths, drive the need for developing table-top microscopes, to overpass the limitations imposed by large facilities, such as their high complexity, maintenance costs and the limited user access. In this paper we present our recent results related to nanoscale imaging using such table-top and desk-top EUV/SXR microscopes. Their construction is based on a double stream gas puff target laser plasma source. The double stream gas puff target EUV and SXR sources, coupled with Fresnel zone plates (FZPs) represent a suitable platform for microscopy experiments in transmission mode, employing SXR and EUV radiation. It represents a possible complementary technique to synchrotrons and free-electron laser facilities. The sources, which are very easy to be used by a single user, allow for efficient generation of plasma radiation with high SXR/EUV flux. Presented herein compact microscopes, based on that source, allow one to capture SXR and EUV images of various samples, with 50–60 nm half-pitch spatial resolution (corresponding to a Rayleigh resolution of 100–120 nm) and exposure time of the order of few seconds. Thus, herein, we would like to present our recent developments and progress in compact desk-top SXR/EUV microscopy employing laser plasma gas puff target sources, showing examples of acquired images and possible applications
Biological Applications of Short Wavelength Microscopy Based on Compact, Laser-Produced Gas-Puff Plasma Source
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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