WorldWideScience

Sample records for vis vis asociada

  1. Atelier de vliegende vis

    NARCIS (Netherlands)

    W.P.H. Bosems

    2002-01-01

    Fontys Hogeschool SPH is in januari 2001 gestart met een atelier voor kunstzinnige vorming: 'de vliegende vis'. Bij de vliegende vis maken jongeren met een verstandelijke handicap kennis met hun creatieve mogelijkheden en ontwikkelen deze verder onder deskundige begeleiding. Studenten van de

  2. Virtual Interactive Space (VIS)

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2015-01-01

    This paper shares code that enables the making of a Virtual Interactive Space (VIS) where the skin of the invisible active sensor area is dynamically responsive to the velocity of a limb e.g. hand. Used in proprioception training of movement the patch is at the core of the author’s Reafferentation...

  3. emotionVis

    DEFF Research Database (Denmark)

    Zimmerman, Chris; Stein, Mari-Klara; Hardt, Daniel

    2016-01-01

    With increasingly high volumes of conversations across social media, the rapid detection of emotions is of significant strategic value to industry prac‐ titioners. Summarizing large volumes of text with computational linguistics and visual analytics allows for several new possibilities from general...... trend detection to specific applications in marketing practice, such as monitoring product launches, campaigns and public relations milestones. After collecting 1.6 million user-tagged feelings from 12 million online posts that mention emotions, we utilized machine learning techniques towards building...... an automatic ‘feelings meter’; a tool for both researchers and practitioners to automatically detect emotional dimensions from text. Following several iterations, the test version has now taken shape as emotionVis, a dashboard prototype for inferring emotions from text while presenting the results for visual...

  4. uVis Studio

    DEFF Research Database (Denmark)

    Pantazos, Kostas; Kuhail, Mohammad Amin; Lauesen, Søren

    2013-01-01

    developers to interact and view the visualization from the end-user's perspective without switching workspace, and Auto-Completion; a feature of the Property Grid that provides suggestions not only for the formula language syntax but also for the tables, the table elds and the relationships in the database......Vis Studio. Instead of programming, developers apply a Drag-Drop-Set-View-Interact approach. Developers bind controls to data, and the Studio gives immediate visual feedback in the Design Panel. This is a novel feature, called What-You-Bind-Is-What- You-Get. The Studio also provides Modes that allow....... We conducted a usability study with six developers to evaluate if the Studio and its features enhance cognition and facilitate the visualization development. The results show that developers appreciated the Drag-Drop-Set- View-Interact approach, the What-You-Bind-Is-What-You-Get, the Auto...

  5. Le juge constitutionnel colombien vis-

    Directory of Open Access Journals (Sweden)

    Marzia Dalto

    2011-12-01

    Full Text Available Esta contribución trata del desplazamiento forzado en Colombia. En particular, este artículo se enfoca sobre el papel específico de la Corte Constitucional colombiana como defensora de los derechos humanos de las personas desplazadas, como juez y al mismo tiempo como actor de políticas públicas. La Corte Constitucional colombiana ha declarado el “estado de cosas inconstitucional” vis-

  6. Gender and area of specialization vis-à-vis students' enrolments in ...

    African Journals Online (AJOL)

    Gender and area of specialization vis-à-vis students' enrolments in undergraduate degree programmes by platform in Public Universities in Kenya. ... The analysis undertook majorly the quantitative pathway using percentages and Chi Square. The overall findings have shown a discrepancy in students' enrolment per ...

  7. Rates and pattern of ovule abortion vis-à-vis in situ pollen ...

    Indian Academy of Sciences (India)

    The species under investigation also showed an appreciable amount of ovule abortion. The ovule abortion in pistils was found to be non-random, with the peduncular ovule aborting at a higher rate than the stylar one. The rates and patterns of ovule abortion were studied vis-à-vis in situ pollen germination and were ...

  8. The Equality of Sexes in J.S.Mill Vis-A-Vis the Participation of ...

    African Journals Online (AJOL)

    Taking from the data from this enquiry, an attempt is made at studying the situation vis-a-vis J. S Mill.s argument for the equality of sexes. While not suggesting any intention to trek all the allies of the experience of women in the Nigerian labour and economy, this piece adopts a new method to tackle the problem, by arguing ...

  9. SAHM:VisTrails (Software for Assisted Habitat Modeling for VisTrails): training course

    Science.gov (United States)

    Holcombe, Tracy

    2014-01-01

    VisTrails is an open-source management and scientific workflow system designed to integrate the best of both scientific workflow and scientific visualization systems. Developers can extend the functionality of the VisTrails system by creating custom modules for bundled VisTrails packages. The Invasive Species Science Branch of the U.S. Geological Survey (USGS) Fort Collins Science Center (FORT) and the U.S. Department of the Interior’s North Central Climate Science Center have teamed up to develop and implement such a module—the Software for Assisted Habitat Modeling (SAHM). SAHM expedites habitat modeling and helps maintain a record of the various input data, the steps before and after processing, and the modeling options incorporated in the construction of an ecological response model. There are four main advantages to using the SAHM:VisTrails combined package for species distribution modeling: (1) formalization and tractable recording of the entire modeling process; (2) easier collaboration through a common modeling framework; (3) a user-friendly graphical interface to manage file input, model runs, and output; and (4) extensibility to incorporate future and additional modeling routines and tools. In order to meet increased interest in the SAHM:VisTrails package, the FORT offers a training course twice a year. The course includes a combination of lecture, hands-on work, and discussion. Please join us and other ecological modelers to learn the capabilities of the SAHM:VisTrails package.

  10. Diferentes visões sobre a cidade

    Directory of Open Access Journals (Sweden)

    Veriano Takuji Miura

    2010-06-01

    Full Text Available A paisagem urbana sempre exerceu um fascínio sobre os homens. Ela tem sido, ao mesmo tempo, sonho e pesadelo de um tempo. Em diferentes momentos, a paisagem urbana tem sido abordada de modo a expressar as singularidades de seu tempo. Nesse sentido, o objetivo deste artigo é trazer uma discussão sobre as diferentes visões da cidade propostas por acadêmicos, cineastas e romancistas. Desde a visão romantizada das cidades da Idade Média, de Ítalo Calvino, até as “cidades virtuais” de Pierre Lévy, destaca-se o longo percurso da chamada “aventura da modernidade”.

  11. ODYSSEY THEMIS VIS ALB V2.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The THEMIS VIS-RDR data set contains the spatially registered, visible albedo images derived from the projected radiance (VIS-GEO) products. Each image header...

  12. Fisiologia da visão binocular

    OpenAIRE

    Bicas Harley E. A.

    2004-01-01

    A visão binocular de seres humanos resulta da superposição quase completa dos campos visuais de cada olho, o que suscita discriminação perceptual de localizações espaciais de objetos relativamente ao observador (localização egocêntrica) bem mais fina (estereopsia), mas isso ocorre em, apenas, uma faixa muito estreita (o horóptero). Aquém e além dela, acham-se presentes diplopia e confusão, sendo necessária supressão fisiológica (cortical) para evitá-las. Analisa-se a geometria do horóptero e ...

  13. Recent hydrogeologic study of the Vis island

    Directory of Open Access Journals (Sweden)

    Janislav Kapelj

    2002-12-01

    Full Text Available The Vis Island belongs to the group of the Middle Dalmatian islands. It comprises an area of about 90.2 km2. Morphologically, three belts of highlands and two depressions with karst poljes are significant. The highest point on the island is Hum with 587 m a.s.l. theisland’s water supply is organized from the water-supply station “Korita”, situated in the central part of island, in tectonically formed depression. There are two additional capturedobjects: the well K-1 above the Komiža town and the spring “Pizdica”. The most important hydrogeological role on the island have two hydrogeological barriers, one in the KomižaBay, completely made of impermeable igneous and clastic rocks, and another one, the recently recognized relative barrier in the area of Dra~evo, Plisko and Velo polje. Since the island karst aquifer is in permanent dynamic relation with seawater, classical geologic,structural and hydrogeologic investigations have been performed with application of hydrogeochemical methods taking into account the natural chemical tracer content of groundwater and its variations in different hydrologic and vegetation conditions. Precipitationregime is very unfavorable with regard to the recharging of island’s aquifer, because dry periods are usually very long. During the summer tourist season, when the number of inhabitants and fresh water consumption considerably increase, amounts of island’sgroundwater suitable for water supply and irrigation rapidly decrease. Sometimes, insufficient quantity of fresh water on the Vis Island causes restrictions. Concerning the development of tourist potential and the present agricultural activities, summer lack ofwater is a serious restrictive factor. Some results of the performed hydrogeological study, important as a basis for island’s fresh water potential assessment, will be presented.

  14. Visualization Software for VisIT Java Client

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    The VisIT Java Client (JVC) library is a lightweight thin client that is designed and written purely in the native language of Java (the Python & JavaScript versions of the library use the same concept) and communicates with any new unmodified standalone version of VisIT, a high performance computing parallel visualization toolkit, over traditional or web sockets and dynamically determines capabilities of the running VisIT instance whether local or remote.

  15. GenVisR: Genomic Visualizations in R.

    Science.gov (United States)

    Skidmore, Zachary L; Wagner, Alex H; Lesurf, Robert; Campbell, Katie M; Kunisaki, Jason; Griffith, Obi L; Griffith, Malachi

    2016-10-01

    Visualizing and summarizing data from genomic studies continues to be a challenge. Here, we introduce the GenVisR package to addresses this challenge by providing highly customizable, publication-quality graphics focused on cohort level genome analyses. GenVisR provides a rapid and easy-to-use suite of genomic visualization tools, while maintaining a high degree of flexibility by leveraging the abilities of ggplot2 and Bioconductor. GenVisR is an R package available via Bioconductor (https://bioconductor.org/packages/GenVisR) under GPLv3. Support is available via GitHub (https://github.com/griffithlab/GenVisR/issues) and the Bioconductor support website. obigriffith@wustl.edu or mgriffit@wustl.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  16. [Dr Lorenzo Dojmi di Delupis- the "Leopard" from Vis].

    Science.gov (United States)

    Jamnicki Dojmi, Mirko

    2011-01-01

    Dr Lorenzo Dojmi di Delupis (1845-1927) was a descendant of a respectful aristocratic family from Vis. His father was Peter Dojmi di Delupis (1809-1886), an attorney, a moderate pro-Italian autonomist, and a mayor of Vis, and his mother was Margherita Siminati. As soon as he graduated from the Medical University of Graz in 1870, he joined the Ottoman army as a physician for a two-year journey in which he reached as far as Baghdad and Basra. He left notes about this dramatic, juvenile adventure in his diaries. In 1878, he married a Viennese girl Maria Neidl and brought her home to Vis, where he got a position of municipal doctor. He had an extraordinary diagnosing acuity, great sympathy for patients, and was always willing to help, which is why he was adored by all the people of Vis, whether they agreed with his autonomist ideas or not, and soon became "the father of Vis". He was the first to warn of leprosy in Dalmatia, when he diagnosed two cases in Vis. Beside medicine and politics, he was also a passionate botanist. He was the first to seed palms in Vis and to grow a palm nursery with his agronomist son Peter Dojmi, for the whole of Dalmatia. He also tried breeding ostriches and growing Mexican coffee. He funded a small meteorological station in Vis, and planned to open a health resort with professor Schröter from Vienna. Even though Lorenzo Dojmi di Delupis held the great Italian culture very dear, his vocation as a physician and humanist inclination never let him burn with the fervour of a political extremist. Thanks to his psychophysical stability, he overcame numerous difficulties in life and retained faith in people. All these traits evoke Prince Salina, the leading character of the renowned novel Il gattopardo (The Leopard) by Giuseppe Tomasi di Lampedusa, which is why the author has so entitled this article "The Gattopardo of Vis".

  17. VisTool: A user interface and visualization development system

    DEFF Research Database (Denmark)

    Xu, Shangjin

    system – to simplify user interface development. VisTool allows user interface development without real programming. With VisTool a designer assembles visual objects (e.g. textboxes, ellipse, etc.) to visualize database contents. In VisTool, visual properties (e.g. color, position, etc.) can be formulas....... However, it is more difficult to follow the classical usability approach for graphical presentation development. These difficulties result from the fact that designers cannot implement user interface with interactions and real data. We developed VisTool – a user interface and visualization development...... interface objects and properties. We built visualizations such as Lifelines, Parallel Coordinates, Heatmap, etc. to show that the formula-based approach is powerful enough for building customized visualizations. The evaluation with Cognitive Dimensions shows that the formula-based approach is cognitively...

  18. Outcomes-based Teaching for Brain-based Learning Vis-à-vis Pedagogical Content Knowledge

    Directory of Open Access Journals (Sweden)

    Reynaldo B. Inocian

    2016-05-01

    Full Text Available The study determined the essential elements of an Outcomes-based Teaching and Learning (OBTL component of an Outcomes-based Education (OBE cycle. It sought to answer these objectives: (1 extrapolate notable teaching attributes based on the actual teaching demonstration of the 7 subjects; (2 describe each of the OBTL’s quadrant elements (3 design a prototype for an integrated arts-based OBTL.This study utilized a case analysis of the actual observation of recurring subtleties exhibited by the seven subject demonstrators during the In-service Training (INSET held last October 27, 2015 in one of the city divisions in Cebu, Philippines. Each of them was rated based on the specific skills used according to Hermann’s Learning Quadrants, after a short lecture on pedagogical content knowledge (PCK.A documentation of a sample Lesson Plan (LP for Quadrant Modelling for Teaching (QMT was juxtaposed as a noble exemplar.The quest for outcomes-based teaching for brain-based learning vis-à-vis pedagogical content knowledge or PCK cascaded with more brain-based inspired learning activities among teacher-demonstrators, with less emphasis on creativity, thus a teaching exemplar was created as part of its modelling. Though, an INSET in the public schools enhanced opportunities to exhibit teaching attributes such as: vivacity, sense of humor, creativity, inquisitiveness, concentration, cautiousness, and dynamism in the achievement of the 21st century skills, however these attributes remained uniquely apparent in every individual teacher. Dreaming to acquire many of these attributes among individual teachers propelled their authentic experience and sincerity to integrate appropriate OBTL activities, which emphasized its four spiral elements, by which the learners would:own knowledge in discovering experiences (sarili, master skills in critical evaluation (husay, engage understating and reflection in dialogical abstraction (saysay, and achieve wonderment in

  19. Le juge constitutionnel colombien vis-à-vis du déplacement forcé

    Directory of Open Access Journals (Sweden)

    Marzia Dalto

    2011-12-01

    Full Text Available Esta contribución trata del desplazamiento forzado en Colombia. En particular, este artículo se enfoca sobre el papel específico de la Corte Constitucional colombiana como defensora de los derechos humanos de las personas desplazadas, como juez y al mismo tiempo como actor de políticas públicas. La Corte Constitucional colombiana ha declarado el “estado de cosas inconstitucional” vis-à-vis de la situación de las personas desplazadas: esto implica que se trata de una situación dramática cuya solución necesita la intervención de muchas instituciones públicas. En el marco de este paper estaré demostrando cómo la Corte Constitucional colombiana se vuelve, de facto, como un actor que orienta las políticas públicas, para garantizar los derechos efectivos de las personas desplazadas. En particular, desde el 2004 el juez constitucional ha implementado un sistema de seguimiento al cumplimiento de las órdenes dictadas por la Sentencia T-025 del 2004, para que sea para las víctimas que son sujetos de especial protección constitucional, como mujeres, comunidades afrocolombianas, indígenas, niños y discapacitados. Consideramos que el caso colombiano es relevante porque el juez constitucional tiene un papel de suprema importancia, que podría contribuir a un nuevo modelo para otras experiencias que cuenten con instituciones del Estado íntegras, en el marco de un conflicto armado.

  20. UV-VIS-NIR spectroscopy and microscopy of heterogeneous catalysts.

    Science.gov (United States)

    Schoonheydt, Robert A

    2010-12-01

    This critical review article discusses the characterization of heterogeneous catalysts by UV-VIS-NIR spectroscopy and microscopy with special emphasis on transition metal ion containing catalysts. A review is given of the transitions, that can be observed in the UV-VIS-NIR region and the peculiarities of catalytic solids that have to be taken into account. This is followed by a short discussion of the techniques that have been developed over the years: diffuse reflectance spectroscopy, UV-VIS microscopy, in situ or operando spectroscopy, the combination of UV-VIS spectroscopy with other spectroscopic techniques, with chemometrics and with quantum chemistry. In the third part of this paper four successes of UV-VIS-NIR spectroscopy and microscopy are discussed; (1) coordination of transition metal ions to surface oxygens; (2) quantitative determination of the oxidation states of transition metal ions; (3) characterization of active sites and (4) study of the distribution of transition metal ions and carbocations in catalytic bodies, particles and crystals (104 references).

  1. UV-VIS absorption spectroscopy: Lambert-Beer reloaded

    Science.gov (United States)

    Mäntele, Werner; Deniz, Erhan

    2017-02-01

    UV-VIS absorption spectroscopy is used in almost every spectroscopy laboratory for routine analysis or research. All spectroscopists rely on the Lambert-Beer Law but many of them are less aware of its limitations. This tutorial discusses typical problems in routine spectroscopy that come along with technical limitations or careless selection of experimental parameters. Simple rules are provided to avoid these problems.

  2. TROPOMI and TROPI: UV/VIS/NIR/SWIR instruments

    NARCIS (Netherlands)

    Levelt, P.F.; Oord, G.H.J. van den; Dobber, M.; Eskes, H.; Weele, M. van; Veefkind, P.; Oss, R. van; Aben, I.; Jongma, R.T.; Landgraf, J.; Vries, J. de; Visser, H.

    2006-01-01

    TROPOMI (Tropospheric Ozone-Monitoring Instrument) is a five-channel UV-VIS-NIR-SWIR non-scanning nadir viewing imaging spectrometer that combines a wide swath (114°) with high spatial resolution (10 × 10 km 2). The instrument heritage consists of GOME on ERS-2, SCIAMACHY on Envisat and, especially,

  3. VIS/NIR imaging application for honey floral origin determination

    NARCIS (Netherlands)

    Minaei, Saeid; Shafiee, Sahameh; Polder, Gerrit; Moghadam-Charkari, Nasrolah; Ruth, van Saskia; Barzegar, Mohsen; Zahiri, Javad; Alewijn, Martin; Kuś, Piotr M.

    2017-01-01

    Nondestructive methods are of utmost importance for honey characterization. This study investigates the potential application of VIS-NIR hyperspectral imaging for detection of honey flower origin using machine learning techniques. Hyperspectral images of 52 honey samples were taken in

  4. Outlier detection in UV/Vis spectrophotometric data

    NARCIS (Netherlands)

    Lepot, M.J.; Aubin, Jean Baptiste; Clemens, F.H.L.R.; Mašić, Alma

    2017-01-01

    UV/Vis spectrophotometers have been used to monitor water quality since the early 2000s. Calibration of these devices requires sampling campaigns to elaborate relations between recorded spectra and measured concentrations. In order to build robust calibration data sets, several spectra must be

  5. UV/VIS/NIR imaging technologies: challenges and opportunities

    Science.gov (United States)

    Kuroda, Rihito; Sugawa, Shigetoshi

    2015-05-01

    Challenges and opportunities of ultraviolet (UV), visible (VIS) and near-infrared (NIR) light imaging technologies are overviewed in this paper. For light detectors and image sensors for UV/VIS/NIR imaging, it is required that they have high sensitivity for wide spectral light waveband or targeted narrow waveband as well as the high stability of light sensitivity toward UV light based on cost effective technology. Wide spectral response, high sensitivity and high stability advanced Si photodiode (PD) pn junction formation technology based on the flattened Si surface and high transmittance on-chip optical filter formation technology were developed. A linear photodiode array (PDA), wide dynamic range and ultrahigh speed CMOS image sensors employing the developed technology were fabricated and their advanced performances are described in this paper.

  6. Compact high-resolution VIS/NIR hyperspectral sensor

    Science.gov (United States)

    Hyvärinen, Timo; Herrala, Esko; Procino, Wes; Weatherbee, Oliver

    2011-06-01

    Current hyperspectral imagers are either bulky with good performance, or compact with only moderate performance. This paper presents a new hyperspectral technology which overcomes this drawback, and makes it possible to integrate extremely compact and high performance push-broom hyperspectral imagers for Unmanned Aerial Vehicles (UAV) and other demanding applications. Hyperspectral imagers in VIS/NIR, SWIR, MWIR and LWIR spectral ranges have been implemented. This paper presents the measured performance attributes for a VIS/NIR imager which covers 350 to 1000 nm with spectral resolution of 3 nm. The key innovation is a new imaging spectrograph design which employs both transmissive and reflective optics in order to achieve high light throughput and large spatial image size in an extremely compact format. High light throughput is created by numerical aperture of F/2.4 and high diffraction efficiency. Image distortions are negligible, keystone being gimbals. In addition to laboratory characterization, results from a flight test mission are presented.

  7. UV-VIS absorption spectroscopy: Lambert-Beer reloaded.

    Science.gov (United States)

    Mäntele, Werner; Deniz, Erhan

    2017-02-15

    UV-VIS absorption spectroscopy is used in almost every spectroscopy laboratory for routine analysis or research. All spectroscopists rely on the Lambert-Beer Law but many of them are less aware of its limitations. This tutorial discusses typical problems in routine spectroscopy that come along with technical limitations or careless selection of experimental parameters. Simple rules are provided to avoid these problems. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. VariVis: a visualisation toolkit for variation databases

    Directory of Open Access Journals (Sweden)

    Smith Timothy D

    2008-04-01

    Full Text Available Abstract Background With the completion of the Human Genome Project and recent advancements in mutation detection technologies, the volume of data available on genetic variations has risen considerably. These data are stored in online variation databases and provide important clues to the cause of diseases and potential side effects or resistance to drugs. However, the data presentation techniques employed by most of these databases make them difficult to use and understand. Results Here we present a visualisation toolkit that can be employed by online variation databases to generate graphical models of gene sequence with corresponding variations and their consequences. The VariVis software package can run on any web server capable of executing Perl CGI scripts and can interface with numerous Database Management Systems and "flat-file" data files. VariVis produces two easily understandable graphical depictions of any gene sequence and matches these with variant data. While developed with the goal of improving the utility of human variation databases, the VariVis package can be used in any variation database to enhance utilisation of, and access to, critical information.

  9. Migratory Trends in the Czech Republic: “Divergence or Convergence” vis-a-vis the Developed World?

    Directory of Open Access Journals (Sweden)

    Dušan Drbohlav

    2002-09-01

    Full Text Available The main goal of this paper is to analyse whether the geopolitical and socio-economic integration and “harmonisation” of the Czech Republic with Western Europe is accompanied by a divergence or convergence of the Czech migratory reality vis-a-vis the developed western world. When testing resemblance two kinds of measurements are used: 1 quantitative – (in terms of the numbers of international migrants, and 2 “qualitative” – a in terms of regularities linked with the migration itself and those that tackle mutual relationships among immigration, the socio-economic development of the destination country and subjective attitudes of the majority population towards minority groups: 3 hypotheses are tested in this regard; b in terms of migratory policies and practices. The results clearly show us that convergence rather than divergence is characteristic of the current migratory trends in the Czech Republic as compared to the developed world, mainly Western Europe.

  10. Assessment of the Awareness and Practice of Women vis-à-vis Breast Self-Examination in Fasa in 2011

    Directory of Open Access Journals (Sweden)

    Hadis Rastad

    2013-06-01

    Full Text Available Background & Objective: Breast cancer is one of the most important causes of women's mortality the world over. Breast self-examination (BSE is a method that often leads to detect breast cancer in the early stage. This study aimed at assessing the awareness and practice of women in the city of FASA vis-à-vis BSE.  Materials & Methods: In this descriptive-analytical study , 300 women over 15 years old who referred to the health centers of Fasa were chosen via the clustered method. A questionnaire comprising items about the patients’ demographics as well as their awareness and practice regarding BSE was completed for all the study population by a trained midwife through interviews. Subsequently, descriptive statistics , x2, and t-test were employed for analysis using SPSS Software ( version 15 .   Results: Fifty-five per cent of the cases had poor knowledge and 90% had poor practice. There was a significant correlation between knowledge and practice (p value < 0.0001. The highest level of knowledge was found among those with university levels of education. There was also a significant correlation between practice and educational levels (p value < 0.0001.   Conclusion: Given that the majority of the women under study had poor knowledge and function vis-à-vis BSE, it seems advisable that regular and systematic training programs be devised in relation to breast cancer prevention strategies such as practical classes on BSE , breast clinical examination, and mammography in order to raise awareness among women about the need to perform BSE.

  11. BirdVis: visualizing and understanding bird populations.

    Science.gov (United States)

    Ferreira, Nivan; Lins, Lauro; Fink, Daniel; Kelling, Steve; Wood, Chris; Freire, Juliana; Silva, Cláudio

    2011-12-01

    Birds are unrivaled windows into biotic processes at all levels and are proven indicators of ecological well-being. Understanding the determinants of species distributions and their dynamics is an important aspect of ecology and is critical for conservation and management. Through crowdsourcing, since 2002, the eBird project has been collecting bird observation records. These observations, together with local-scale environmental covariates such as climate, habitat, and vegetation phenology have been a valuable resource for a global community of educators, land managers, ornithologists, and conservation biologists. By associating environmental inputs with observed patterns of bird occurrence, predictive models have been developed that provide a statistical framework to harness available data for predicting species distributions and making inferences about species-habitat associations. Understanding these models, however, is challenging because they require scientists to quantify and compare multiscale spatialtemporal patterns. A large series of coordinated or sequential plots must be generated, individually programmed, and manually composed for analysis. This hampers the exploration and is a barrier to making the cross-species comparisons that are essential for coordinating conservation and extracting important ecological information. To address these limitations, as part of a collaboration among computer scientists, statisticians, biologists and ornithologists, we have developed BirdVis, an interactive visualization system that supports the analysis of spatio-temporal bird distribution models. BirdVis leverages visualization techniques and uses them in a novel way to better assist users in the exploration of interdependencies among model parameters. Furthermore, the system allows for comparative visualization through coordinated views, providing an intuitive interface to identify relevant correlations and patterns. We justify our design decisions and present case

  12. A Notation Based Approach To Film Pre-vis

    OpenAIRE

    Chakravarthy, Ajay; Beales, Richard; Jung, Yvonne; Wagner, Sebastian; Jung, Christoph; Yannopoulous, Angelos; Koutsoutos, Stefanos; Schiffmann, Rolf; Hedtke, Rolf; Saenen, Ignace

    2010-01-01

    This paper describes ANSWER which is a new approach to the creative process of film production. It is based on a symbolic notation system called Director Notation (DN) through which film directors are free to express their creative intent much like a music composer uses musical notation. The notation populates a semantic model which is machine processable and this input is automatically converted into a lightweight 3D pre-vis. ANSWER is integrated with DFT BONES Dailies, so that in post-produ...

  13. Os conteúdos das visões da ayahuasca

    OpenAIRE

    Shanon,Benny

    2003-01-01

    Este artigo examina os conteúdos das alucinações visuais induzidas pela infusão psicotrópica ayahuasca. Ele faz parte de uma investigação fenomenológica mais ampla que busca estudar a ayahuasca de uma perspectiva psicológico-cognitiva. (Até agora, quase todos os estudos da ayahuasca partiram das ciências naturais ou da antropologia.) Análises comparativas quantitativas revelam que certos itens de conteúdo específico são especialmente prevalescentes em visões da ayahuasca e se reencontram em r...

  14. In situ Vis NIR and Raman spectroelectrochemistry at fullerene peapods

    Science.gov (United States)

    Kavan, Ladislav; Dunsch, Lothar; Kataura, Hiromichi

    2002-07-01

    The population of valence-band electronic states of fullerene peapods (C 60@SWCNT) was tuned electrochemically in acetonitrile solutions. Electrochemistry of peapods was dominated by their capacitive charging without distinct faradaic processes. In situ Vis-NIR spectra of peapods showed similar features as those of empty nanotubes. Electrochemical charging caused reversible bleaching of the transitions between Van Hove singularities. This bleaching was mirrored by quenching of resonance Raman spectra of the tube-related modes. The A g(2) mode of C 60 exhibits considerable intensity increase upon anodic doping of peapods, but this mode is not enhanced at cathodic charging.

  15. Limewashed mural paintings as seen by VIS-IR reflectography

    Science.gov (United States)

    Fontana, R.; Striova, J.; Barucci, M.; Pampaloni, E.; Raffaelli, M.; Pezzati, L.; Mariotti, P.

    2015-06-01

    Near-Infrared (NIR) reflectography is a well-established technique for painting diagnostics, offering a fundamental contribution to the conservation of paintings. Since the '80s it has been routinely applied to study the execution technique of the author, as well as the presence of pentimenti, retouches, integrations or underdrawing. In the last decades IR reflectography has been extended to the visible (VIS) spectral range, providing information about the pigment composition. Up to now the multispectral analysis is still applied at an experimental level, as the processing of the image set is not straightforward. Rarely multispectral VIS-IR application has been applied to frescos, probably due to the lack, in most cases, of a scattering background. In this work we present the results provided by a multispectral scanning device based on single sensor acquisition, working in the 380-2500 nm spectral range, that is a laboratory prototype specifically built for research-grade imaging. The technique have been applied on a mock up simulating a mural painting substrate where an underdrawing, made of either carbon or iron-gall ink, was covered by different surface layers of limewash, the so-called scialbo.

  16. Uric acid detection using uv-vis spectrometer

    Science.gov (United States)

    Norazmi, N.; Rasad, Z. R. Abdul; Mohamad, M.; Manap, H.

    2017-10-01

    The aim of this research is to detect uric acid (UA) concentration using Ultraviolet-Visible (UV-Vis) spectrometer in the Ultraviolet (UV) region. Absorption technique was proposed to detect different uric acid concentrations and its UV absorption wavelength. Current practices commonly take a lot of times or require complicated structures for the detection process. By this proposed spectroscopic technique, every concentration can be detected and interpreted into an absorbance value at a constant wavelength peak in the UV region. This is due to the chemical characteristics belong to the uric acid since it has a particular absorption cross-section, σ which can be calculated using Beer’s Lambert law formula. The detection performance was displayed using Spectrasuite sofware. It showed fast time response about 3 seconds. The experiment proved that the concentrations of uric acid were successfully detected using UV-Vis spectrometer at a constant absorption UV wavelength, 294.46 nm in a low time response. Even by an artificial sample of uric acid, it successfully displayed a close value as the ones reported with the use of the medical sample. It is applicable in the medical field and can be implemented in the future for earlier detection of abnormal concentration of uric acid.

  17. Vis Medicatrix naturae: does nature "minister to the mind"?

    Directory of Open Access Journals (Sweden)

    Logan Alan C

    2012-04-01

    Full Text Available Abstract The healing power of nature, vis medicatrix naturae, has traditionally been defined as an internal healing response designed to restore health. Almost a century ago, famed biologist Sir John Arthur Thomson provided an additional interpretation of the word nature within the context of vis medicatrix, defining it instead as the natural, non-built external environment. He maintained that the healing power of nature is also that associated with mindful contact with the animate and inanimate natural portions of the outdoor environment. A century on, excessive screen-based media consumption, so-called screen time, may be a driving force in masking awareness of the potential benefits of nature. With global environmental concerns, rapid urban expansion, and mental health disorders at crisis levels, diminished nature contact may not be without consequence to the health of the individual and the planet itself. In the context of emerging research, we will re-examine Sir J. Arthur Thomson's contention that the healing power of the nature-based environment - green space, forests and parks in particular - extends into the realm of mental health and vitality.

  18. Vis Medicatrix naturae: does nature "minister to the mind"?

    Science.gov (United States)

    Logan, Alan C; Selhub, Eva M

    2012-04-03

    The healing power of nature, vis medicatrix naturae, has traditionally been defined as an internal healing response designed to restore health. Almost a century ago, famed biologist Sir John Arthur Thomson provided an additional interpretation of the word nature within the context of vis medicatrix, defining it instead as the natural, non-built external environment. He maintained that the healing power of nature is also that associated with mindful contact with the animate and inanimate natural portions of the outdoor environment. A century on, excessive screen-based media consumption, so-called screen time, may be a driving force in masking awareness of the potential benefits of nature. With global environmental concerns, rapid urban expansion, and mental health disorders at crisis levels, diminished nature contact may not be without consequence to the health of the individual and the planet itself. In the context of emerging research, we will re-examine Sir J. Arthur Thomson's contention that the healing power of the nature-based environment - green space, forests and parks in particular - extends into the realm of mental health and vitality.

  19. [Design of a portable UV-Vis spectrophotometer].

    Science.gov (United States)

    Wan, Feng; Sun, Hong-wei; Fan, Shi-fu

    2006-04-01

    In the present paper, a method for how to design a portable UV-Vis spectrophotometer is introduced. The Hamamatsu multichannel detector S3904-1024Q and a flat field concave grating are employed to design a miniaturized dispersion system. In order to solve the contradiction between the spectral width and energy-utilizing ratio of the light source, a multi-band optical fiber is employed, one side of which is arranged to be rectangle as the entrance slit. The touch screen is employed as the input and output system of the spectrophotometer, and the miniaturized fiber-optic UV-Vis light source is employed as the light source. The research results and testing results of the prototype show that the new spectrophotometer based on the authors' new method is of miniaturization in volume(190 mm x 170 mm x 100 mm), can realize multi-wavelength-detection on-line, and is easily handled (touch screen control), and its performance accords with the Chinese national standard.

  20. VIS/NIR imaging application for honey floral origin determination

    Science.gov (United States)

    Minaei, Saeid; Shafiee, Sahameh; Polder, Gerrit; Moghadam-Charkari, Nasrolah; van Ruth, Saskia; Barzegar, Mohsen; Zahiri, Javad; Alewijn, Martin; Kuś, Piotr M.

    2017-11-01

    Nondestructive methods are of utmost importance for honey characterization. This study investigates the potential application of VIS-NIR hyperspectral imaging for detection of honey flower origin using machine learning techniques. Hyperspectral images of 52 honey samples were taken in transmittance mode in the visible/near infrared (VIS-NIR) range (400-1000 nm). Three different machine learning algorithms were implemented to predict honey floral origin using honey spectral images. These methods, included radial basis function (RBF) network, support vector machine (SVM), and random forest (RF). Principal component analysis (PCA) was also exploited for dimensionality reduction. According to the obtained results, the best classifier (RBF) achieved a precision of 94% in a fivefold cross validation experiment using only the first two PCs. Mapping of the classifier results to the test set images showed 90% accuracy for honey images. Three types of honey including buckwheat, rapeseed and heather were classified with 100% accuracy. The proposed approach has great potential for honey floral origin detection. As some other honey properties can also be predicted using image features, in addition to floral origin detection, this method may be applied to predict other honey characteristics.

  1. Mapping Ecology of Literacies in Educational Setting: The Case of Local Mother Tongues Vis-a-Vis Urdu and English Languages in Pakistan

    Science.gov (United States)

    Manan, Syed Abdul; David, Maya Khemlani

    2014-01-01

    This study critically examines the literacy levels of undergraduate students in Pakistan to compare and contrast the proficiency levels, particularly reading and writing of their mother tongues versus Urdu and English, and to study real and perceived vitality of local/regional mother tongues vis-à-vis Urdu and English. The research investigated…

  2. Viz-A-Vis: toward visualizing video through computer vision.

    Science.gov (United States)

    Romero, Mario; Summet, Jay; Stasko, John; Abowd, Gregory

    2008-01-01

    In the established procedural model of information visualization, the first operation is to transform raw data into data tables [1]. The transforms typically include abstractions that aggregate and segment relevant data and are usually defined by a human, user or programmer. The theme of this paper is that for video, data transforms should be supported by low level computer vision. High level reasoning still resides in the human analyst, while part of the low level perception is handled by the computer. To illustrate this approach, we present Viz-A-Vis, an overhead video capture and access system for activity analysis in natural settings over variable periods of time. Overhead video provides rich opportunities for long-term behavioral and occupancy analysis, but it poses considerable challenges. We present initial steps addressing two challenges. First, overhead video generates overwhelmingly large volumes of video impractical to analyze manually. Second, automatic video analysis remains an open problem for computer vision.

  3. InfoVis Interaction Techniques in Animation of Recursive Programs

    Directory of Open Access Journals (Sweden)

    Antonio Pérez-Carrasco

    2010-02-01

    Full Text Available Algorithm animations typically assist in educational tasks aimed simply at achieving understanding. Potentially, animations could assist in higher levels of cognition, such as the analysis level, but they usually fail in providing this support because they are not flexible or comprehensive enough. In particular, animations of recursion provided by educational systems hardly support the analysis of recursive algorithms. Here we show how to provide full support to the analysis of recursive algorithms. From a technical point of view, animations are enriched with interaction techniques inspired by the information visualization (InfoVis field. Interaction tasks are presented in seven categories, and deal with both static visualizations and dynamic animations. All of these features are implemented in the SRec system, and visualizations generated by SRec are used to illustrate the article.

  4. Fabricating a UV-Vis and Raman Spectroscopy Immunoassay Platform.

    Science.gov (United States)

    Hanson, Cynthia; Israelsen, Nathan D; Sieverts, Michael; Vargis, Elizabeth

    2016-11-10

    Immunoassays are used to detect proteins based on the presence of associated antibodies. Because of their extensive use in research and clinical settings, a large infrastructure of immunoassay instruments and materials can be found. For example, 96- and 384-well polystyrene plates are available commercially and have a standard design to accommodate ultraviolet-visible (UV-Vis) spectroscopy machines from various manufacturers. In addition, a wide variety of immunoglobulins, detection tags, and blocking agents for customized immunoassay designs such as enzyme-linked immunosorbent assays (ELISA) are available. Despite the existing infrastructure, standard ELISA kits do not meet all research needs, requiring individualized immunoassay development, which can be expensive and time-consuming. For example, ELISA kits have low multiplexing (detection of more than one analyte at a time) capabilities as they usually depend on fluorescence or colorimetric methods for detection. Colorimetric and fluorescent-based analyses have limited multiplexing capabilities due to broad spectral peaks. In contrast, Raman spectroscopy-based methods have a much greater capability for multiplexing due to narrow emission peaks. Another advantage of Raman spectroscopy is that Raman reporters experience significantly less photobleaching than fluorescent tags(1). Despite the advantages that Raman reporters have over fluorescent and colorimetric tags, protocols to fabricate Raman-based immunoassays are limited. The purpose of this paper is to provide a protocol to prepare functionalized probes to use in conjunction with polystyrene plates for direct detection of analytes by UV-Vis analysis and Raman spectroscopy. This protocol will allow researchers to take a do-it-yourself approach for future multi-analyte detection while capitalizing on pre-established infrastructure.

  5. Calibration curves for quantifying praseodymium by UV-VIS; Curvas de calibracion para cuantificar praseodimio por UV-VIS

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, R.; Lopez G, H.; Rojas H, A. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: robertssd1199@yahoo.com.mx

    2007-07-01

    The UV-Vis spectroscopic technique was used to determine the absorption bands depending on the concentration from the praseodymium solutions at pH3. Those more appropriate were in the wavelength of 215 nm, for concentrations of 0.0001-0.026 M, of 481nm, 468 nm and 443 nm, for concentrations of 0.026-0.325 M, and of 589 nm, for concentrations of 0.026-0.65 M of the praseodymium. To these wavelengths the calibration curves were determined, which presented correlation coefficients between 0.9976 and 0.9999 except of the absorption of 589 nm that gave R{sup 2} = 0.9014. (Author)

  6. VisIVO: A Library and Integrated Tools for Large Astrophysical Dataset Exploration

    Science.gov (United States)

    Becciani, U.; Costa, A.; Ersotelos, N.; Krokos, M.; Massimino, P.; Petta, C.; Vitello, F.

    2012-09-01

    VisIVO provides an integrated suite of tools and services that can be used in many scientific fields. VisIVO development starts in the Virtual Observatory framework. VisIVO allows users to visualize meaningfully highly-complex, large-scale datasets and create movies of these visualizations based on distributed infrastructures. VisIVO supports high-performance, multi-dimensional visualization of large-scale astrophysical datasets. Users can rapidly obtain meaningful visualizations while preserving full and intuitive control of the relevant parameters. VisIVO consists of VisIVO Desktop - a stand-alone application for interactive visualization on standard PCs, VisIVO Server - a platform for high performance visualization, VisIVO Web - a custom designed web portal, VisIVOSmartphone - an application to exploit the VisIVO Server functionality and the latest VisIVO features: VisIVO Library allows a job running on a computational system (grid, HPC, etc.) to produce movies directly with the code internal data arrays without the need to produce intermediate files. This is particularly important when running on large computational facilities, where the user wants to have a look at the results during the data production phase. For example, in grid computing facilities, images can be produced directly in the grid catalogue while the user code is running in a system that cannot be directly accessed by the user (a worker node). The deployment of VisIVO on the DG and gLite is carried out with the support of EDGI and EGI-Inspire projects. Depending on the structure and size of datasets under consideration, the data exploration process could take several hours of CPU for creating customized views and the production of movies could potentially last several days. For this reason an MPI parallel version of VisIVO could play a fundamental role in increasing performance, e.g. it could be automatically deployed on nodes that are MPI aware. A central concept in our development is thus to

  7. O impacto da visão monocular congênita versus adquirida na qualidade de visão autorrelatada

    Directory of Open Access Journals (Sweden)

    Marcelo Caram Ribeiro Fernandes

    2010-12-01

    Full Text Available Objetivos: Quando a visão de um olho está preservada (visão monocular e há alto risco, baixo prognóstico e/ou recursos limitados para a cirurgia do olho contralateral, não é claro se o beneficio da binocularidade supera o da reorientação para visão monocular. O objetivo é quantificar o impacto da qualidade de visão referida entre a condição binocular e monocular e, nesse último caso, entre congênita e adquirida. Métodos: Pacientes com acuidade visual (AV com AV>0,5 em cada olho foram submetidos ao questionário estruturado de 14 perguntas (VF-14, onde a pontuação de 0 a 100 indica o nível de satisfação do paciente com sua visão, variando de baixo a alto respectivamente. Dados epidemiológicos e pontuações dos quatro grupos foram registrados e submetidos à análise estatística. Resultados: A entrevista pelo VF-14 com 56 indivíduos revelou que a pontuação mais alta foi similar entre os controles e os portadores de visão monocular congênita, e níveis intermediários e baixos foram obtidos por indivíduos com visão monocular adquirida e cegos bilaterais, respectivamente (p<0,001. As atividades mais difíceis para os indivíduos com visão monocular adquirida foram identificar letras pequenas, reconhecer pessoas, distinguir sinais de trânsito e assistir TV. Conclusão: O estudo confirmou que a perda da visão tem impacto desfavorável no desempenho referido das atividades sendo maior na visão monocular adquirida do que na congênita. Os dados sugerem que medidas de reabilitação devem ser consideradas para melhorar a qualidade da visão em doenças intratáveis ou de alto risco ou de baixo prognóstico.

  8. Os conteúdos das visões da ayahuasca

    Directory of Open Access Journals (Sweden)

    Benny Shanon

    2003-10-01

    Full Text Available Este artigo examina os conteúdos das alucinações visuais induzidas pela infusão psicotrópica ayahuasca. Ele faz parte de uma investigação fenomenológica mais ampla que busca estudar a ayahuasca de uma perspectiva psicológico-cognitiva. (Até agora, quase todos os estudos da ayahuasca partiram das ciências naturais ou da antropologia. Análises comparativas quantitativas revelam que certos itens de conteúdo específico são especialmente prevalescentes em visões da ayahuasca e se reencontram em relatos de informantes de diferentes origens socioculturais. Os resultados são discutidos teoricamente à luz de considerações tanto psicológicas como antropológicas.This paper examines the contents of the visual hallucinations induced by the Amazonian psychotropic brew ayahuasca. It is part of a comprehensive phenomenological investigation attempting to study ayahuasca from a cognitive-psychological perspective. (So far, practically all studies of ayahuasca pertained either to the natural sciences or to anthropology. Comparative quantitative analyses reveal that some specific content items are especially prevalent in ayahuasca visions, and that these are encountered in the reports of informants from different personal and socio-cultural backgrounds. Theoretically, the findings are discussed in light of both psychological and anthropological considerations.

  9. VisMashup: streamlining the creation of custom visualization applications.

    Science.gov (United States)

    Santos, Emanuele; Lins, Lauro; Ahrens, James; Freire, Juliana; Silva, Cláudio

    2009-01-01

    Visualization is essential for understanding the increasing volumes of digital data. However, the process required to create insightful visualizations is involved and time consuming. Although several visualization tools are available, including tools with sophisticated visual interfaces, they are out of reach for users who have little or no knowledge of visualization techniques and/or who do not have programming expertise. In this paper, we propose VisMashup, a new framework for streamlining the creation of customized visualization applications. Because these applications can be customized for very specific tasks, they can hide much of the complexity in a visualization specification and make it easier for users to explore visualizations by manipulating a small set of parameters. We describe the framework and how it supports the various tasks a designer needs to carry out to develop an application, from mining and exploring a set of visualization specifications (pipelines), to the creation of simplified views of the pipelines, and the automatic generation of the application and its interface. We also describe the implementation of the system and demonstrate its use in two real application scenarios.

  10. Design of VisSWIR continuous zoom optical system

    Science.gov (United States)

    Yang, Mingyang; Yang, Hongtao; Qu, Rui; Mei, Chao; Zhou, Zuofeng

    2017-02-01

    For 640 pixel×512 pixel cooled staring focal plane array detector, a VisSWIR wideband continuous zoom optical system with 7X zoom range is presented based on the pattern of the negative zoom group and compensating lens group. The zoom system provides continuous changed in the field of view from narrow to the wide. The zoom optical system works in the range of 0.4μm 1.7μm, F number is 4, the pixel of the detector is 15μm. It realizes 20mm 140mm continuous zoom with a smooth zoom path and provided high image quality with the whole zoom range, the zoom ratio is 7:1. The modulation transfer function(MTF) for the system is above 0.5 within the whole focal length range at spatial frequency of 34lp/mm and it almost approaches the diffraction limit. RMS value of spot diameter was investigation, the maximum distortion value is less than 5% and the surface type of all lens applied is spherical. Moreover, the cam curve after optimization is given by the optical design software Code V macro. The design results provide that the zoom system has the small size, high resolution, excellent image quality and the smooth cam curve etc.

  11. Medico - historical study of "Visŭcikă" (Cholera).

    Science.gov (United States)

    Prasad, P V V

    2005-01-01

    The Sanskrit word Visŭcikă refers to a condition in which vitiated văta dŏşa causes pain like pricking with a needle over the body. It occurs in a person suffering with ajĭrna (indigestion) and its detailed description is available in Ayurvedic literature. This disease has its existence in India since ancient times; it has also been referred in Mahăhărata and Tripitikas. Its etiology, signs, symptoms, complications, prognosis and treatment etc. as described in Ayurveda may be correlated with the disease Cholera, which is commonly known as "Haiza" in Hindi. In Greek language, the word Cholera means a flow of bile or the bilious disease. Cholera is an acute infectious diarrheal disease, caused by comma bacillus or vibrio cholerae sero groups 01 or 0139. Aretaetus, Benjamin Rush, Chadwick, John Snow, Robert Koch, etc. were some of the pioneers in Cholera research. Medico- historical importance of Cholera, its transmission, description and references from Ayurvedic texts etc., are being presented in this article.

  12. A tiny VIS-NIR snapshot multispectral camera

    Science.gov (United States)

    Geelen, Bert; Blanch, Carolina; Gonzalez, Pilar; Tack, Nicolaas; Lambrechts, Andy

    2015-03-01

    Spectral imaging can reveal a lot of hidden details about the world around us, but is currently confined to laboratory environments due to the need for complex, costly and bulky cameras. Imec has developed a unique spectral sensor concept in which the spectral unit is monolithically integrated on top of a standard CMOS image sensor at wafer level, hence enabling the design of compact, low cost and high acquisition speed spectral cameras with a high design flexibility. This flexibility has previously been demonstrated by imec in the form of three spectral camera architectures: firstly a high spatial and spectral resolution scanning camera, secondly a multichannel snapshot multispectral camera and thirdly a per-pixel mosaic snapshot spectral camera. These snapshot spectral cameras sense an entire multispectral data cube at one discrete point in time, extending the domain of spectral imaging towards dynamic, video-rate applications. This paper describes the integration of our per-pixel mosaic snapshot spectral sensors inside a tiny, portable and extremely user-friendly camera. Our prototype demonstrator cameras can acquire multispectral image cubes, either of 272x512 pixels over 16 bands in the VIS (470-620nm) or of 217x409 pixels over 25 bands in the VNIR (600-900nm) at 170 cubes per second for normal machine vision illumination levels. The cameras themselves are extremely compact based on Ximea xiQ cameras, measuring only 26x26x30mm, and can be operated from a laptop-based USB3 connection, making them easily deployable in very diverse environments.

  13. Interactive network visualization in Jupyter notebooks: visJS2jupyter.

    Science.gov (United States)

    Rosenthal, Sara Brin; Len, Julia; Webster, Mikayla; Gary, Aaron; Birmingham, Amanda; Fisch, Kathleen M

    2018-01-01

    Network biology is widely used to elucidate mechanisms of disease and biological processes. The ability to interact with biological networks is important for hypothesis generation and to give researchers an intuitive understanding of the data. We present visJS2jupyter, a tool designed to embed interactive networks in Jupyter notebooks to streamline network analysis and to promote reproducible research. The tool provides functions for performing and visualizing useful network operations in biology, including network overlap, network propagation around a focal set of genes, and co-localization of two sets of seed genes. visJS2jupyter uses the JavaScript library vis.js to create interactive networks displayed within Jupyter notebook cells with features including drag, click, hover, and zoom. We demonstrate the functionality of visJS2jupyter applied to a biological question, by creating a network propagation visualization to prioritize risk-related genes in autism. The visJS2jupyter package is distributed under the MIT License. The source code, documentation and installation instructions are freely available on GitHub at https://github.com/ucsd-ccbb/visJS2jupyter. The package can be downloaded at https://pypi.python.org/pypi/visJS2jupyter. sbrosenthal@ucsd.edu. Supplementary data are available at Bioinformatics online.

  14. VisFlow - Web-based Visualization Framework for Tabular Data with a Subset Flow Model.

    Science.gov (United States)

    Yu, Bowen; Silva, Claudio T

    2017-01-01

    Data flow systems allow the user to design a flow diagram that specifies the relations between system components which process, filter or visually present the data. Visualization systems may benefit from user-defined data flows as an analysis typically consists of rendering multiple plots on demand and performing different types of interactive queries across coordinated views. In this paper, we propose VisFlow, a web-based visualization framework for tabular data that employs a specific type of data flow model called the subset flow model. VisFlow focuses on interactive queries within the data flow, overcoming the limitation of interactivity from past computational data flow systems. In particular, VisFlow applies embedded visualizations and supports interactive selections, brushing and linking within a visualization-oriented data flow. The model requires all data transmitted by the flow to be a data item subset (i.e. groups of table rows) of some original input table, so that rendering properties can be assigned to the subset unambiguously for tracking and comparison. VisFlow features the analysis flexibility of a flow diagram, and at the same time reduces the diagram complexity and improves usability. We demonstrate the capability of VisFlow on two case studies with domain experts on real-world datasets showing that VisFlow is capable of accomplishing a considerable set of visualization and analysis tasks. The VisFlow system is available as open source on GitHub.

  15. Visible Color Properties of Mars at Sub-100 m Resolutions from Mars Odyssey THEMIS/VIS

    Science.gov (United States)

    Bell, J. F., III; McConnochie, T. H.; Wolff, M. J.; Savransky, D.; Stiglitz, B.; Malin, M.; Christensen, P. R.; Mehall, G. L.; Cherednik, L. L.; Bender, K. C.; THEMIS Science Team

    2003-05-01

    The Mars Odyssey THEMIS instrument's Visible Imaging Subsystem (VIS) has been acquiring one to five color visible wavelength images of Mars at spatial scales of 18 to 72 m/pixel since February 2002. As of late-June 2003 VIS had acquired approximately 8600 image sequences covering approximately 9% of the Martian surface. Roughly two thirds of the VIS images acquired to date have been single-band images (mostly 654 nm); the remaining have been acquired in two or more bands, with most of those acquired through all five VIS filters (425, 540, 654, 749, and 860 nm). Nearly all of the two nominal MER landing ellipses have been imaged by VIS in at least the 654 nm band. We have developed a VIS calibration pipeline using pre-flight and in-flight calibration data to correct for instrumental effects and convert the images to radiance units. Five-color radiance data are also being used to generate true color composite views of VIS scenes. Work is also underway to quantify the surface vs. atmospheric components of the observed radiances using radiative transfer modeling and simultaneous MGS/TES and THEMIS/IRS observations. Initial analyses of the VIS multispectral data are focusing on the search for and identification of anomalous color units associated with intercrater deposits, dunes, wind streaks, and gullies. In general,we are finding that color variability is subtle on Mars even at the fine spatial scale of VIS observations. These results have important implications for testing of competing hypotheses dealing with weathering or alteration of the martian surface, as well as for planning of future MRO CRISM or HiRISE observations at higher spectral or spatial resolution. This work is supported by the NASA Mars Odyssey Participating Scientist Program.

  16. A stretchable nanowire UV-Vis-NIR photodetector with high performance.

    Science.gov (United States)

    Yoo, Jewon; Jeong, Sanghwa; Kim, Sungjee; Je, Jung Ho

    2015-03-11

    A simple direct-writing technique can be used to fabricate a stretchable UV-vis-NIR nanowire photodetector (NWPD) consisting of PbS quantum dot (QD)-poly(3-hexylthiopehene) (P3HT) hybrid NWs. The hybrid NWPD shows superior sensitivity and response speed in the UV-vis to NIR range. The stretchable UV-vis-NIR NWPD shows a nearly identical photoresponse under extreme (up to 100%) and repeated (up to 100 cycles) stretching conditions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. REFLECTANCE UV-VIS AND UV RESONANCE RAMAN SPECTROSCOPY IN CHARACTERIZATION OF KRAFT PULPS

    OpenAIRE

    Anni Lähdetie; Tiina Liitiä; Tarja Tamminen; Anna-Stiina Jääskeläinen

    2009-01-01

    Reflectance UV-Vis spectroscopy and UV resonance Raman (UVRR) spectroscopy are both nondestructive techniques that are applicable to study trace concentrations of lignin in-situ. In this study, unbleached and bleached softwood kraft pulps were analyzed by reflectance UV-Vis (k/s) and UVRR spectroscopy to follow lignin and hexenuronic acid (HexA) contents and structural changes in residual lignin. The height of the lignin band in the UV-Vis spectra (280 nm) correlated well with the lignin band...

  18. VisBOL: Web-Based Tools for Synthetic Biology Design Visualization.

    Science.gov (United States)

    McLaughlin, James Alastair; Pocock, Matthew; Mısırlı, Göksel; Madsen, Curtis; Wipat, Anil

    2016-08-19

    VisBOL is a Web-based application that allows the rendering of genetic circuit designs, enabling synthetic biologists to visually convey designs in SBOL visual format. VisBOL designs can be exported to formats including PNG and SVG images to be embedded in Web pages, presentations and publications. The VisBOL tool enables the automated generation of visualizations from designs specified using the Synthetic Biology Open Language (SBOL) version 2.0, as well as a range of well-known bioinformatics formats including GenBank and Pigeoncad notation. VisBOL is provided both as a user accessible Web site and as an open-source (BSD) JavaScript library that can be used to embed diagrams within other content and software.

  19. High Spatial Resolution Visible Color Units on Mars from the Mars Odyssey THEMIS/VIS Instrument

    Science.gov (United States)

    Bell, J. F., III; McConnochie, T.; Savransky, D.; Stiglitz, B.; Wolff, M. J.; Christensen, P. R.; Mehall, G.; James, P. B.; Malin, M.; Caplinger, M.; Ravine, M.; Cherednik, L. L.; Bender, K. C.; Murray, K.; Themis Science Team

    2003-07-01

    This presentation describes the calibration and new results from the Mars Odyssey THEMIS/VIS instrument, which is obtaining five-color visible wavelength images from Mars orbit at scales of 18 72 m/pixel.

  20. VisTrails is an open-source scientific workflow and provenance management system

    CSIR Research Space (South Africa)

    Mthombeni, Thabo DM

    2011-12-01

    Full Text Available VisTrails is an open-source scientific workflow and provenance management system that provides support for simulations, data exploration and visualization. Whereas workflows have been traditionally used to automate repetitive tasks, for applications...

  1. Vispubdata.org: A Metadata Collection About IEEE Visualization (VIS) Publications.

    Science.gov (United States)

    Isenberg, Petra; Heimerl, Florian; Koch, Steffen; Isenberg, Tobias; Xu, Panpan; Stolper, Charles D; Sedlmair, Michael; Chen, Jian; Moller, Torsten; Stasko, John

    2017-09-01

    We have created and made available to all a dataset with information about every paper that has appeared at the IEEE Visualization (VIS) set of conferences: InfoVis, SciVis, VAST, and Vis. The information about each paper includes its title, abstract, authors, and citations to other papers in the conference series, among many other attributes. This article describes the motivation for creating the dataset, as well as our process of coalescing and cleaning the data, and a set of three visualizations we created to facilitate exploration of the data. This data is meant to be useful to the broad data visualization community to help understand the evolution of the field and as an example document collection for text data visualization research.

  2. Dense-shell glycodendrimers: UV/Vis and electron paramagnetic resonance study of metal ion complexation

    National Research Council Canada - National Science Library

    Dietmar Appelhans; Ulrich Oertel; Roberto Mazzeo; Hartmut Komber; Jan Hoffmann; Steffen Weidner; Bernhard Brutschy; Brigitte Voit; Maria Francesca Ottaviani

    2010-01-01

    ...(propyleneimine) glycodendrimers ranging up to the fifth generation that have either a dense maltose or maltotriose shell was investigated by UV/Vis spectroscopy and electron paramagnetic resonance (EPR...

  3. Utility values in the visually impaired: comparing time-trade off and VisQoL.

    Science.gov (United States)

    Gothwal, Vijaya K; Bagga, Deepak K

    2013-08-01

    Visual impairment (VI) negatively affects quality of life (QoL). Utilities represent a way of measuring the QoL impact associated with a particular health state, like VI, and are also useful in economic evaluations of health care interventions. Utilities can be determined either directly or indirectly. Here we determine whether the Vision and Quality of Life Index, VisQoL (indirect approach), is acceptable to use in patients with VI in an urban setting in South India; whether the VisQoL utility values, derived from an Australian sample of both visually impaired and normally sighted participants, demonstrate agreement (if any) with direct utilities, determined by time trade-off (TTO), from visually impaired South Indian patients; and determine the relationship between utilities and self-reported visual disability. Three hundred forty-nine adults with VI were administered the two-item TTO item, six-item VisQoL, and the 16-item Andhra Pradesh Eye Disease-Visual Function Questionnaire (APEDS-VFQ) in a face-to-face interview. The VisQoL utilities were derived from the utility scoring algorithm. Rasch-scaled scores of the APEDS-VFQ were obtained using the conversion scores sheets. Agreement between TTO and utilities VisQoL was assessed using the Bland-Altman method. All participants (response rate, 100%) completed the VisQoL as compared with 72% for the TTO. There was no statistically significant difference in the mean utilities from the two methods (0.65 ± 0.31 by TTO vs. 0.66 ± 0.27 by VisQoL, p = 0.67). However, the 95% limits of agreement on the Bland-Altman plot were wide (-0.65, 0.67), implying a lack of agreement between the methods. The VisQoL relates relatively strongly with APEDS-VFQ as compared with TTO (TTO vs. APEDS-VFQ, r = -0.23, VisQoL vs. APEDS-VFQ, r = -0.66, z = -6.70; p evaluation tend to disagree in our patients with VI. Given the high completion rates of the VisQoL as compared with the TTO, the VisQoL may be a suitable alternative for utility

  4. VisIt: An End-User Tool for Visualizing and Analyzing Very Large Data

    Energy Technology Data Exchange (ETDEWEB)

    Childs, Hank; Brugger, Eric; Whitlock, Brad; Meredith, Jeremy; Ahern, Sean; Pugmire, David; Biagas, Kathleen; Miller, Mark; Weber, Gunther H.; Krishnan, Hari; Fogal, Thomas; Sanderson, Allen; Garth, Christoph; Bethel, E. Wes; Camp, David; Ruebel, Oliver; Durant, Marc; Favre, Jean; Navratil, Paul

    2012-11-01

    VisIt is a popular open source tool for visualizing and analyzing big data. It owes its success to its foci of increasing data understanding, large data support, and providing a robust and usable product, as well as its underlying design that fits today's supercomputing landscape. This report, which draws heavily from an earlier publication at the SciDAC Conference in 2011 describes the VisIt project and its accomplishments.

  5. GridVis: Visualisation of Island-based parallel genetic algorithms

    OpenAIRE

    Lutton, Evelyne; Gilbert, Hugo; Cancino, Waldo; Bach, Benjamin; Parrend, Pierre; Pierre, Collet

    2014-01-01

    Island Model parallel genetic algorithms rely on various mi- gration models and their associated parameter settings. A fine under- standing of how the islands interact and exchange informations is an im- portant issue for the design of efficient algorithms. This article presents GridVis, an interactive tool for visualising the exchange of individuals and the propagation of fitness values between islands. We performed sev- eral experiments on a grid and on a cluster to evaluate GridVis' abilit...

  6. Integration of the HTC Vive into the medical platform MeVisLab

    Science.gov (United States)

    Egger, Jan; Gall, Markus; Wallner, Jürgen; de Almeida Germano Boechat, Pedro; Hann, Alexander; Li, Xing; Chen, Xiaojun; Schmalstieg, Dieter

    2017-03-01

    Virtual Reality (VR) is an immersive technology that replicates an environment via computer-simulated reality. VR gets a lot of attention in computer games but has also great potential in other areas, like the medical domain. Examples are planning, simulations and training of medical interventions, like for facial surgeries where an aesthetic outcome is important. However, importing medical data into VR devices is not trivial, especially when a direct connection and visualization from your own application is needed. Furthermore, most researcher don't build their medical applications from scratch, rather they use platforms, like MeVisLab, Slicer or MITK. The platforms have in common that they integrate and build upon on libraries like ITK and VTK, further providing a more convenient graphical interface to them for the user. In this contribution, we demonstrate the usage of a VR device for medical data under MeVisLab. Therefore, we integrated the OpenVR library into MeVisLab as an own module. This enables the direct and uncomplicated usage of head mounted displays, like the HTC Vive under MeVisLab. Summarized, medical data from other MeVisLab modules can directly be connected per drag-and-drop to our VR module and will be rendered inside the HTC Vive for an immersive inspection.

  7. HTC Vive MeVisLab integration via OpenVR for medical applications.

    Directory of Open Access Journals (Sweden)

    Jan Egger

    Full Text Available Virtual Reality, an immersive technology that replicates an environment via computer-simulated reality, gets a lot of attention in the entertainment industry. However, VR has also great potential in other areas, like the medical domain, Examples are intervention planning, training and simulation. This is especially of use in medical operations, where an aesthetic outcome is important, like for facial surgeries. Alas, importing medical data into Virtual Reality devices is not necessarily trivial, in particular, when a direct connection to a proprietary application is desired. Moreover, most researcher do not build their medical applications from scratch, but rather leverage platforms like MeVisLab, MITK, OsiriX or 3D Slicer. These platforms have in common that they use libraries like ITK and VTK, and provide a convenient graphical interface. However, ITK and VTK do not support Virtual Reality directly. In this study, the usage of a Virtual Reality device for medical data under the MeVisLab platform is presented. The OpenVR library is integrated into the MeVisLab platform, allowing a direct and uncomplicated usage of the head mounted display HTC Vive inside the MeVisLab platform. Medical data coming from other MeVisLab modules can directly be connected per drag-and-drop to the Virtual Reality module, rendering the data inside the HTC Vive for immersive virtual reality inspection.

  8. UV-Vis reflection spectroscopy under variable angle incidence at the air-liquid interface.

    Science.gov (United States)

    Roldán-Carmona, Cristina; Rubia-Payá, Carlos; Pérez-Morales, Marta; Martín-Romero, María T; Giner-Casares, Juan J; Camacho, Luis

    2014-03-07

    The UV-Vis reflection spectroscopy (UV-Vis-RS) in situ at the air-liquid interface provides information about tilt and aggregation of chromophores in Langmuir monolayers. This information is particularly important given in most cases the chromophore is located at the polar region of the Langmuir monolayer. This region of the Langmuir monolayers has been hardly accessible by other experimental techniques. In spite of its enormous potential, the application of UV-Vis-RS has been limited mainly to reflection measurements under light normal incidence or at lower incidence angles than the Brewster angle. Remarkably, this technique is quite sensitive to the tilt of the chromophores at values of incidence angles close to or larger than the Brewster angle. Therefore, a novel method to obtain the order parameter of the chromophores at the air-liquid interface by using s- and p-polarized radiation at different incidence angles is proposed. This method allowed for the first time the experimental observation of the two components with different polarization properties of a single UV-Vis band at the air-liquid interface. The method of UV-Vis spectroscopy under variable angle incidence is presented as a new tool for obtaining rich detailed information on Langmuir monolayers.

  9. HTC Vive MeVisLab integration via OpenVR for medical applications.

    Science.gov (United States)

    Egger, Jan; Gall, Markus; Wallner, Jürgen; Boechat, Pedro; Hann, Alexander; Li, Xing; Chen, Xiaojun; Schmalstieg, Dieter

    2017-01-01

    Virtual Reality, an immersive technology that replicates an environment via computer-simulated reality, gets a lot of attention in the entertainment industry. However, VR has also great potential in other areas, like the medical domain, Examples are intervention planning, training and simulation. This is especially of use in medical operations, where an aesthetic outcome is important, like for facial surgeries. Alas, importing medical data into Virtual Reality devices is not necessarily trivial, in particular, when a direct connection to a proprietary application is desired. Moreover, most researcher do not build their medical applications from scratch, but rather leverage platforms like MeVisLab, MITK, OsiriX or 3D Slicer. These platforms have in common that they use libraries like ITK and VTK, and provide a convenient graphical interface. However, ITK and VTK do not support Virtual Reality directly. In this study, the usage of a Virtual Reality device for medical data under the MeVisLab platform is presented. The OpenVR library is integrated into the MeVisLab platform, allowing a direct and uncomplicated usage of the head mounted display HTC Vive inside the MeVisLab platform. Medical data coming from other MeVisLab modules can directly be connected per drag-and-drop to the Virtual Reality module, rendering the data inside the HTC Vive for immersive virtual reality inspection.

  10. Study of Vis/NIR spectroscopy measurement on acidity of yogurt

    Science.gov (United States)

    He, Yong; Feng, Shuijuan; Wu, Di; Li, Xiaoli

    2006-09-01

    A fast measurement of pH of yogurt using Vis/NIR-spectroscopy techniques was established in order to measuring the acidity of yogurt rapidly. 27 samples selected separately from five different brands of yogurt were measured by Vis/NIR-spectroscopy. The pH of yogurt on positions scanned by spectrum was measured by a pH meter. The mathematical model between pH and Vis/NIR spectral measurements was established and developed based on partial least squares (PLS) by using Unscramble V9.2. Then 25 unknown samples from 5 different brands were predicted based on the mathematical model. The result shows that The correlation coefficient of pH based on PLS model is more than 0.890, and standard error of calibration (SEC) is 0.037, standard error of prediction (SEP) is 0.043. Through predicting the pH of 25 samples of yogurt from 5 different brands, the correlation coefficient between predictive value and measured value of those samples is more than 0918. The results show the good to excellent prediction performances. The Vis/NIR spectroscopy technique had a significant greater accuracy for determining the value of pH. It was concluded that the VisINIRS measurement technique can be used to measure pH of yogurt fast and accurately, and a new method for the measurement of pH of yogurt was established.

  11. Miniaturization of environmental chemical assays in flowing systems: The lab-on-a-valve approach vis-à-vis lab-on-a-chip microfluidic devices

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald

    2007-01-01

    The analytical capabilities of the microminiaturised lab-on-a-valve (LOV) module integrated into a microsequential injection (muSI) fluidic system in terms of analytical chemical performance, microfluidic handling and on-line sample processing are compared to those of the micro total analysis...... systems (muTAS), also termed lab-on-a-chip (LOC). This paper illustrates, via selected representative examples, the potentials of the LOV scheme vis-à-vis LOC microdevices for environmental assays. By means of user-friendly programmable flow and exploitation of the interplay between the thermodynamics...... and the kinetics of the chemical reactions at will, LOV allows accommodation of reactions which, at least at the present stage, are not feasible by application of microfluidic LOC systems. Thus, in LOV one may take advantage of kinetic discriminations schemes, where even subtle differences in reactions...

  12. Implementation of DSP Based Cost Effective Inverter Fed Induction Motor Drive with VisSim

    Science.gov (United States)

    Mohanty, Nalin K.; Muthu, Ranganath

    2012-03-01

    The implementation of a Digital Signal Processor (DSP) based high-performance cost effective fed Induction Motor drive with VisSim/Embedded Controls Developer (ECD) is presented in this paper. In the experimental work VisSim/ECD software automatically converts the in built block diagram to C code and compiles, links, and downloads the code to DSP processor TMS320F2812. The DSP processor generates the required PWM to a cost effective ie four switch 3-phase (FSTPI) inverter. The power circuit of FSTPI fed drive system consists of an IGBT based FSTPI bridge inverter module feeding to a 5 hp three-phase squirrel cage induction motor. In this work the speed of induction motor output is shown by the GUI of VisSim/ECD and SPWM pulses, line voltages and line current output curves are shown using digital storage oscilloscope to demonstrate the feasibility of the system.

  13. VisTrails SAHM: visualization and workflow management for species habitat modeling

    Science.gov (United States)

    Morisette, Jeffrey T.; Jarnevich, Catherine S.; Holcombe, Tracy R.; Talbert, Colin B.; Ignizio, Drew; Talbert, Marian; Silva, Claudio; Koop, David; Swanson, Alan; Young, Nicholas E.

    2013-01-01

    The Software for Assisted Habitat Modeling (SAHM) has been created to both expedite habitat modeling and help maintain a record of the various input data, pre- and post-processing steps and modeling options incorporated in the construction of a species distribution model through the established workflow management and visualization VisTrails software. This paper provides an overview of the VisTrails:SAHM software including a link to the open source code, a table detailing the current SAHM modules, and a simple example modeling an invasive weed species in Rocky Mountain National Park, USA.

  14. VisGraB: A Benchmark for Vision-Based Grasping. Paladyn Journal of Behavioral Robotics

    DEFF Research Database (Denmark)

    Kootstra, Gert; Popovic, Mila; Jørgensen, Jimmy Alison

    2012-01-01

    We present a database and a software tool, VisGraB, for benchmarking of methods for vision-based grasping of unknown objects with no prior object knowledge. The benchmark is a combined real-world and simulated experimental setup. Stereo images of real scenes containing several objects in different...... that a large number of grasps can be executed and evaluated while dealing with dynamics and the noise and uncertainty present in the real world images. VisGraB enables a fair comparison among different grasping methods. The user furthermore does not need to deal with robot hardware, focusing on the vision...

  15. Development of nondestructive sorting method for brown bloody eggs using VIS/NIR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hong Seock; Kim, Dae Yong; Kandpal, Lalit Mohan; Lee, Sang Dae; Cho, Byoung Kwan [Dept. of Biosystems Machinery Engineering, College of Agriculture and Life Science, Chungnam National University, Daejeon (Korea, Republic of); Mo, Chang Yeun; Hong, Soon Jung [Rural Development Administration, Jeonju (Korea, Republic of)

    2014-02-15

    The aim of this study was the non-destructive evaluation of bloody eggs using VIS/NIR spectroscopy. The bloody egg samples used to develop the sorting mode were produced by injecting chicken blood into the edges of egg yolks. Blood amounts of 0.1, 0.7, 0.04, and 0.01 mL were used for the bloody egg samples. The wavelength range for the VIS/NIR spectroscopy was 471 to 1154 nm, and the spectral resolution was 1.5nm. For the measurement system, the position of the light source was set to, and the distance between the light source and samples was set to 100 mm. The minimum exposure time of the light source was set to 30 ms to ensure the fast sorting of bloody eggs and prevent heating damage of the egg samples. Partial least squares-discriminant analysis (PLS-DA) was used for the spectral data obtained from VIS/NIR spectroscopy. The classification accuracies of the sorting models developed with blood samples of 0.1, 0.07, 0.04, and 0.01 mL were 97.9%, 98.9%, 94.8%, and 86.45%, respectively. In this study, a novel nondestructive sorting technique was developed to detect bloody brown eggs using spectral data obtained from VIS/NIR spectroscopy.

  16. Quantifying lycopene synthesis and chlorophyll breakdown in tomato fruit using remittance VIS spectroscopy

    NARCIS (Netherlands)

    Schouten, R.E.; Farneti, B.; Tijskens, L.M.M.; Algarra Alarcon, A.; Woltering, E.J.

    2014-01-01

    The aim of this study was to increase the understanding of chlorophyll breakdown and lycopene synthesis at a quantitative level in Solanum lycopersicum fruit. To accomplish this, a kinetic model is proposed describing the transition from chloro- to chromoplast. Remittance VIS spectroscopy was used

  17. UV/Vis and NIR Light-Responsive Spiropyran Self-Assembled Monolayers

    NARCIS (Netherlands)

    Ivashenko, Oleksii; Herpt, Jochem T. van; Feringa, Ben L.; Rudolf, Petra; Browne, Wesley R.

    2013-01-01

    Self-assembled monolayers of a 6-nitro BIPS spiropyran (SP) modified with a disulfide-terminated aliphatic chain were prepared on polycrystalline gold surfaces and characterized by UV/vis absorption, surface-enhanced Raman scattering (SEAS), and X-ray photoelectron spectroscopies (XPS). The SAMs

  18. Simultaneous Determination of Caffeine and Chlorogenic Acids in Green Coffee by UV/Vis Spectroscopy

    National Research Council Canada - National Science Library

    G. Navarra; M. Moschetti; V. Guarrasi; M. R. Mangione; V. Militello; M. Leone

    2017-01-01

    .... The method was based on the use of UV/Vis absorption. It is relevant that the quantification of both caffeine and chlorogenic acids was performed without their preliminary chemical separation despite their spectral overlap in the range 250–350 nm...

  19. Predicting water-holding capacity of intact chicken broiler breast fillets with Vis/NIR spectroscopy

    Science.gov (United States)

    The ability of using visible and near-infrared (Vis/NIR) spectroscopy to predict water-holding capacity (WHC) of intact chicken broiler breast fillets (pectoralis major) was assessed in this study. Boneless and skinless chicken fillets (214 in total) were procured from a commercial processing plant ...

  20. Monitoring en Evaluatie Pilot Zandmotor Fase 2: meetrapportage monstername benthos, vis en strand najaar 2011

    NARCIS (Netherlands)

    Boon, A.R.; Wijsman, J.W.M.

    2012-01-01

    Dit document beschrijft de werkzaamheden die in het najaar van 2011 zijn uitgevoerd ten behoeve van de monstername van sediment, benthos, vis in de vooroever en de lagune, en van sediment en bodemgebonden fauna van het strand ter plaatse van de Zandmotor.

  1. Instrumentation: Photodiode Array Detectors in UV-VIS Spectroscopy. Part II.

    Science.gov (United States)

    Jones, Dianna G.

    1985-01-01

    A previous part (Analytical Chemistry; v57 n9 p1057A) discussed the theoretical aspects of diode ultraviolet-visual (UV-VIS) spectroscopy. This part describes the applications of diode arrays in analytical chemistry, also considering spectroelectrochemistry, high performance liquid chromatography (HPLC), HPLC data processing, stopped flow, and…

  2. Instrumental Analysis in the High School Classroom: UV-Vis Spectroscopy

    Science.gov (United States)

    Erhardt, Walt

    2007-01-01

    Note is presented on the standard lab from a second year chemistry course. The lab "Determining which of the Seven FD&C Food-Approved Dyes are Used in Making Green Skittles", familiarizes students with the operation of the CHEM2000 UV-Vis spectrophorometer.

  3. Ozone Profile Retrieval Algorithm (OPERA) for nadir-looking satellite instruments in the UV-VIS

    NARCIS (Netherlands)

    Van Peet, J.C.A.; Van der A, R.J.; Tuinder, O.N.E.; Wolfram, E.; Salvador, J.; Levelt, P.F.; Kelder, H.M.

    2014-01-01

    For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA) has been further developed. The new version (1.26) of OPERA is capable of retrieving ozone profiles from UV–VIS observations of most nadir-looking satellite instruments like GOME,

  4. Interference-Blind Microfluidic Sensor for Ascorbic Acid Determination by UV/vis Spectroscopy

    DEFF Research Database (Denmark)

    Bi, Hongyan; Oliveira Fernandes, Ana Carolina; Cardoso, Susana

    2016-01-01

    the microfluidic channel, enzyme-catalyzed reaction occurs and only converts the target molecules to its products. The whole process is monitored by an end-channel UV/vis spectroscopic detection. Ascorbate oxidase and L-ascorbic acid (AA) are taken as enzyme-substrate model in this study to investigate...

  5. Flowering and vegetative propagation of pyrethrum (Chrysanthemum cinerariaefolium Vis.) in vivo and in vitro

    NARCIS (Netherlands)

    Roest, S.

    1976-01-01

    The influence of climatic conditions was investigated on flowering behaviour of pyrethrum ( Chrysanthemum cinerariaefolium Vis.). At low temperatures high numbers of plants initiated high numbers of flower heads. Both the development of the initiated flower heads and the

  6. Uma visão geral da gramática funcional

    Directory of Open Access Journals (Sweden)

    Maria Helena de Moura Neves

    2001-02-01

    Full Text Available

    O trabalho apresenta uma visão geral do que vem sendo chamado funcionalismo em lingüística. Contrapõem-se os modelos formalista e funcionalista e examinam-se, em especial, as propostas de gramática funcional de C. S. Dik e de M. A. K. Halliday.

  7. De vis wordt duur(zaam) vervoerd : Openbare eindrapportage AKK-project ACD-03.032

    NARCIS (Netherlands)

    Snels, J.C.M.A.

    2005-01-01

    The project `De vis wordt duur(zaam) vervoerd` focuses on the reduction of the amount of driven kilometres in de supply from producers (i.e. Prime Meat and Seafood Partners) to the wholesaler and the distribution routes of the wholesaler (i.e. Deli XL). The reduction can be reached through (1)

  8. Principal component analysis of UV-VIS-NIR transmission spectra of Moldavian matured wine distillates

    Science.gov (United States)

    Khodasevich, Mikhail A.; Trofimova, Darya V.; Nezalzova, Elena I.

    2011-02-01

    Principal component analysis of UV-VIS-NIR transmission spectra of matured wine distillates (1-40 years aged) produced by three Moldavian manufacturers allows to characterize with sufficient certainty the eleven chemical parameters of considered alcoholic beverages: contents of acetaldehyde, ethyl acetate, furfural, vanillin, syringic aldehyde and acid, etc.

  9. Spectral Estimation of UV-Vis Absorbance Time Series for Water Quality Monitoring

    Directory of Open Access Journals (Sweden)

    Leonardo Plazas-Nossa

    2017-05-01

    Full Text Available Context: Signals recorded as multivariate time series by UV-Vis absorbance captors installed in urban sewer systems, can be non-stationary, yielding complications in the analysis of water quality monitoring. This work proposes to perform spectral estimation using the Box-Cox transformation and differentiation in order to obtain stationary multivariate time series in a wide sense. Additionally, Principal Component Analysis (PCA is applied to reduce their dimensionality. Method: Three different UV-Vis absorbance time series for different Colombian locations were studied: (i El-Salitre Wastewater Treatment Plant (WWTP in Bogotá; (ii Gibraltar Pumping Station (GPS in Bogotá; and (iii San-Fernando WWTP in Itagüí. Each UV-Vis absorbance time series had equal sample number (5705. The esti-mation of the spectral power density is obtained using the average of modified periodograms with rectangular window and an overlap of 50%, with the 20 most important harmonics from the Discrete Fourier Transform (DFT and Inverse Fast Fourier Transform (IFFT. Results: Absorbance time series dimensionality reduction using PCA, resulted in 6, 8 and 7 principal components for each study site respectively, altogether explaining more than 97% of their variability. Values of differences below 30% for the UV range were obtained for the three study sites, while for the visible range the maximum differences obtained were: (i 35% for El-Salitre WWTP; (ii 61% for GPS; and (iii 75% for San-Fernando WWTP. Conclusions: The Box-Cox transformation and the differentiation process applied to the UV-Vis absorbance time series for the study sites (El-Salitre, GPS and San-Fernando, allowed to reduce variance and to eliminate ten-dency of the time series. A pre-processing of UV-Vis absorbance time series is recommended to detect and remove outliers and then apply the proposed process for spectral estimation. Language: Spanish.

  10. [On-line coupling of microcolumn electrophoresis and UV-Vis spectrophotometry].

    Science.gov (United States)

    Li, Lian; He, You-Zhao; Gan, Wu-Er; Wang, Xiao-Kui; Xie, Hai-Yang; Gao, Yong

    2010-03-01

    In the present paper, a laboratory-made high-performance electrophoresis microcolumn unit was prepared for UV-Vis spectrophotometer. X-ray diffraction was used in the preparation of electrophoretic microcolumns. And an analytical technique of microcolumn electrophoresis coupled with UV-Vis spectrophotometry was introduced. Uniform quartz microncrystals were prepared by hydrothermal synthesis. Their crystalline phase and morphology were identified by X-ray diffraction and scanning electron microscope, respectively. The quartz microncrystals were packed into a 2-mm i. d. fused-silica tube to prepare the electrophoretic microcolumn. With 1.5 mmol x L(-1) disodium phosphate buffer solution (pH 11.5) containing 25% (phi) methanol and 10% (phi) acetonitrile, tryptophan, phenylalanine and tyrosine were on-line separated on line and detected by microcolumn electrophoresis coupled with UV-Vis spectrophotometry without derivatization. The limits of detection were 0.037, 0.20 and 0.20 micromol x L(-1), respectively. The separation efficiency of tryptophan was 4.5 x 10(4) plates/m. The sample capacity of the electrophoretic microcolumn achieved 35 microL. It was found that the electrophoretic microcolumn packed with quartz microncrystals was able to limit Joule heat, increase sample capacity and enhance detection sensitivity. The laboratory-made electrophoretic microcolumn could be a high-performance separation unit for conventional UV-Vis spectrophotometer. The on-line coupling of microcolumn electrophoresis and UV-Vis spectrophotometry could separate and determine samples with complicated matrices, reduce zone broadening and enhance separation efficiency, so expand the analytical function of spectrophotometer in the trace analysis of mixed components with overlapped spectra.

  11. VisANT: an online visualization and analysis tool for biological interaction data

    Directory of Open Access Journals (Sweden)

    DeLisi Charles

    2004-02-01

    Full Text Available Abstract Background New techniques for determining relationships between biomolecules of all types – genes, proteins, noncoding DNA, metabolites and small molecules – are now making a substantial contribution to the widely discussed explosion of facts about the cell. The data generated by these techniques promote a picture of the cell as an interconnected information network, with molecular components linked with one another in topologies that can encode and represent many features of cellular function. This networked view of biology brings the potential for systematic understanding of living molecular systems. Results We present VisANT, an application for integrating biomolecular interaction data into a cohesive, graphical interface. This software features a multi-tiered architecture for data flexibility, separating back-end modules for data retrieval from a front-end visualization and analysis package. VisANT is a freely available, open-source tool for researchers, and offers an online interface for a large range of published data sets on biomolecular interactions, including those entered by users. This system is integrated with standard databases for organized annotation, including GenBank, KEGG and SwissProt. VisANT is a Java-based, platform-independent tool suitable for a wide range of biological applications, including studies of pathways, gene regulation and systems biology. Conclusion VisANT has been developed to provide interactive visual mining of biological interaction data sets. The new software provides a general tool for mining and visualizing such data in the context of sequence, pathway, structure, and associated annotations. Interaction and predicted association data can be combined, overlaid, manipulated and analyzed using a variety of built-in functions. VisANT is available at http://visant.bu.edu.

  12. Theoretical Virtual Observatory and Grid Web services: VisIVO and new capabilities

    Science.gov (United States)

    Costa, A.; Becciani, U.; Gheller, C.; Comparato, M.; Larsson, B.

    2007-08-01

    VisIVO is a tool for 3D visualization, it provides an effective and intuitive way of managing, visualizing and analysing the large amount of data produced by observations and numerical simulations. The software is specifically designed to deal with multidimensional data. Catalogues and numerical simulations represent the basic target of VisIVO. The package is written in C++. This poster describes VIsIVO's Grid Web Service (VWS) and its counterpart client side developed in VisIVO. VisIVO's Grid Web Service is developed as a part of the Italian Virtual Observatory, it allows to run applications in grid using the web service technology. The VWS has been designed to work within a Virtual Observatory environment so that the interface for the current application, shown in this poster, and the interfaces for other applications are described by a small and constant piece of WSDL code. Our first application is HOP: an algorithm for finding groups of particles based on the one developed and coded by Daniel Eisenstein & Piet Hut, Institute for Advanced Study, Princeton, NJ. We have developed VWS using Java AXIS libraries for the server side and C++ AXIS libraries for the client side. The access to the computational resources and storage areas is based on grid services in the INFN Production Grid and from this the VWS inherits asynchronous features, scheduling and matching algorithms. HOP was distributed as RPM Package and was installed in the Worker Node Elements of the INFN Production Grid. The idea is to use external tools through the grid avoiding the integration in our application. We can focus on the I/O management of the jobs and on the standardization of the access methods for the different analysis tools improving the scalability of our solution.

  13. Confiabilidade da avaliação da visão funcional para crianças com baixa visão de dois a seis anos: em busca de evidências

    OpenAIRE

    Luciana Drummond de Figueiredo Rossi; Galton Carvalho Vasconcelos; Grace Rego Saliba; Lívia de Castro Magalhães; Angela Maria Anselmo Soares; Silvia Santiago Cordeiro; Regina Helena Caldas de Amorim

    2012-01-01

    OBJETIVOS: Avaliar a confiabilidade interexaminadores, fazer o teste-reteste e verificar a consistência interna da avaliação da visão funcional para crianças com baixa visão de dois a seis anos de idade (AVIF-2 a 6 anos). MÉTODOS: Foram testados sete domínios: fixação visual, seguimento visual, campo visual de confrontação, coordenação olho-mão, visão de contraste, deslocamento no ambiente e visão de cores, em 40 crianças, 20 com baixa visão e 20 sem alterações visuais. A consistência interna...

  14. Spectroscopic (vibrational, NMR and UV-vis.) and quantum chemical investigations on 4-hexyloxy-3-methoxybenzaldehyde.

    Science.gov (United States)

    Abbas, Ashgar; Gökce, Halil; Bahçeli, Semiha

    2016-01-05

    In this study, the 4-hexyloxy-3-methoxybenzaldehyde compound as one of the derivatives of vanillin which is a well known flavoring agent, C14H20O3, has been investigated by experimentally and extensively utilizing density functional theory (DFT) at the B3LYP/6-311++G(d,p) level. In this context, the optimized geometry, vibrational frequencies, (1)H and (13)C NMR chemical shifts, UV-vis. (in gas phase and in methanol solvent) spectra, HOMO-LUMO analysis, molecular electrostatic potential (MEP), thermodynamic parameters and atomic charges of 4-hexyloxy-3-methoxybenzaldehyde have been calculated. In addition, theoretically predicted IR, Raman and UV-vis. (in gas phase and in methanol solvent) spectra of the mentioned molecule have been constructed. The results calculated were compared with the experimental data. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Synthesis, FTIR, UV-Vis and Photoluminescence characterizations of triethanolamine passivated CdO nanostructures.

    Science.gov (United States)

    Anandhan, K; Thilak Kumar, R

    2015-10-05

    In this study, triethanolamine (TEOA) capped CdO nanostructures had been synthesized by wet chemical method annealed at 648K were reported. The structural, morphological and optical properties of the samples were studied by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) with energy dispersive spectra (EDS) analysis, Fourier transform infrared (FTIR) spectroscopy, UV-Vis spectroscopy and Photoluminescence (PL) techniques. The XRD spectrum showed that all the samples were cubic in structure. The presence of functional groups and chemical bonding had been confirmed by FTIR. UV-Vis measurements showed decreased band gap energy for TEOA capped CdO, when compared with uncapped CdO. The PL spectra of the CdO systems showed the red emission. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Photodegradation of ibuprofen under UV-Vis irradiation: mechanism and toxicity of photolysis products.

    Science.gov (United States)

    Li, Fu Hua; Yao, Kun; Lv, Wen Ying; Liu, Guo Guang; Chen, Ping; Huang, Hao Ping; Kang, Ya Pu

    2015-04-01

    The photodegradation of ibuprofen (IBP) in aqueous media was studied in this paper. The degradation mechanism, the reaction kinetics and toxicity of the photolysis products of IBP under UV-Vis irradiation were investigated by dissolved oxygen experiments, quenching experiments of reactive oxygen species (ROS), and toxicity evaluation utilizing Vibrio fischeri. The results demonstrated that the IBP degradation process could be fitted by the pseudo first-order kinetics model. The degradation of IBP by UV-Vis irradiation included direct photolysis and self-sensitization via ROS. The presence of dissolved oxygen inhibited the photodegradation of IBP, which indicated that direct photolysis was more rapid than the self-sensitization. The contribution rates of ·OH and (1)O2 were 21.8 % and 38.6 % in self-sensitization, respectively. Ibuprofen generated a number of intermediate products that were more toxic than the base compound during photodegradation.

  17. FoamVis, A Visualization System for Foam Research: Design and Implementation

    Directory of Open Access Journals (Sweden)

    Dan R. Lipsa

    2015-03-01

    Full Text Available Liquid foams are used in areas such as mineral separation, oil recovery, food and beverage production, sanitation and fire fighting. To improve the quality of products and the efficiency of processes in these areas, foam scientists wish to understand and control foam behaviour. To this end, foam scientists have used foam simulations to model foam behaviour; however, analysing these simulations presents difficult challenges. We describe the main foam research challenges and present the design of FoamVis, the only existing visualization, exploration and analysis application created to address them. We describe FoamVis’ main features, together with relevant design and implementation notes. Our goal is to provide a global overview and individual feature implementation details that would allow a visualization scientist to extend the FoamVis system with new algorithms and adapt it to new requirements. The result is a detailed presentation of the software that is not provided in previous visualization research papers.

  18. An overview of liquid phase microextraction approaches combined with UV-Vis spectrophotometry.

    Science.gov (United States)

    Dehghani Mohammad Abadi, Malihe; Ashraf, Narges; Chamsaz, Mahmoud; Shemirani, Farzaneh

    2012-09-15

    Ultraviolet and visible spectrophotometer has become a popular analytical instrument in the modern day laboratories. However, the low concentrations of many analytes in samples make it difficult to directly measure them by UV-Vis spectrophotometry. This overview focuses on the combinations of microvolume UV-Vis spectrophotometry with miniaturized approaches to sample preparation, namely, single drop microextraction (SDME), dispersive liquid-liquid microextraction (DLLME), cold induced aggregation microextraction (CIAME), in situ solvent formation microextraction (ISSFME), ultrasound assisted emulsification microextraction (USAEME), solidified floating organic drop microextraction (SFODME), and hollow fiber based liquid phase microextraction (HF-LPME) to improve both the selectivity and sensitivity. Integration of these techniques provides unique advantages which include availability, simplicity of operation, low cost, speed, precision and accuracy; hence making them a powerful tool in chemical analysis. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. UV-Vis Action Spectroscopy Reveals a Conformational Collapse in Hydrogen-Rich Dinucleotide Cation Radicals.

    Science.gov (United States)

    Korn, Joseph A; Urban, Jan; Dang, Andy; Nguyen, Huong T H; Tureček, František

    2017-09-07

    We report the generation of deoxyriboadenosine dinucleotide cation radicals by gas-phase electron transfer to dinucleotide dications and their noncovalent complexes with crown ether ligands. Stable dinucleotide cation radicals of a novel hydrogen-rich type were generated and characterized by tandem mass spectrometry and UV-vis photodissociation (UVPD) action spectroscopy. Electron structure theory analysis indicated that upon electron attachment the dinucleotide dications underwent a conformational collapse followed by intramolecular proton migrations between the nucleobases to give species whose calculated UV-vis absorption spectra matched the UVPD action spectra. Hydrogen-rich cation radicals generated from chimeric riboadenosine 5'-diesters gave UVPD action spectra that pointed to novel zwitterionic structures consisting of aromatic π-electron anion radicals intercalated between stacked positively charged adenine rings. Analogies with DNA ionization are discussed.

  20. X-ray diffraction, FTIR, UV-VIS and SEM studies on chromium (III) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Ashutosh; Dwivedi, Jagrati, E-mail: hemu.dwi@gmail.com; Shukla, Kritika [School of Physics, Devi Ahilya University, Khandwa Road, Indore-452001 (India)

    2015-06-24

    Five Chromium (III) complexes have been prepared using Schiff base ligands which derived from benzoin and five different amino acids (H{sub 2}N-R). Samples were characterized by XRD, FTIR, UV-VIS and SEM method. X-Ray diffraction pattern analyzed that all chromium (III) complexes have hexagonal structure and crystalline, in nature, using Bruker D8 Advance instrument. Using VERTAX 70, FTIR spectroscopy reveals that Samples have (C=N), (C-O), (M-N) and (M-O) bonds in the range of 4000-400cm{sup −1}. UV-VIS spectroscopy give information that samples absorb the visible light which is in the range of 380-780nm. For this, Lambda 960 spectrometer used. SEM is designed for studying of the solid objects, using JEOL JSM 5600 instrument.

  1. UV/Vis, MCD and EPR Spectra of Mononuclear Manganese and Molybdenum Complexes

    OpenAIRE

    Westphal, Anne

    2012-01-01

    This PhD thesis deals with the spectroscopic characterization of the electronic structures of mononuclear manganese and molybdenum complexes. At this, in addition to UV/Vis absorption spectroscopy, electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) spectroscopy were applied in this work. Additionally, new procedures for the general analysis of MCD C-term intensities were developed within the scope of this thesis. It is divided into four parts. Following a general p...

  2. Simultaneous Determination of Caffeine and Chlorogenic Acids in Green Coffee by UV/Vis Spectroscopy

    OpenAIRE

    Navarra, G.; Moschetti, M,; Guarrasi, V.; Mangione, M.R.; Militello, V; Leone, M.

    2017-01-01

    A simple method for the simultaneous determination of caffeine and chlorogenic acids content in green coffee was reported. The method was based on the use of UV/Vis absorption. It is relevant that the quantification of both caffeine and chlorogenic acids was performed without their preliminary chemical separation despite their spectral overlap in the range 250–350 nm. Green coffee was extracted with 70% ethanol aqueous solution; then the solution was analyzed by spectroscopy. Quantitative det...

  3. Determination of total flavonoids in three Sedum crude drugs by UV-Vis spectrophotometry.

    Science.gov (United States)

    Chen, Yujie; Wang, Jing; Wan, Dingrong

    2010-10-01

    A simple, rapid UV-Vis spectrophotometry method for the determination of total flavonoids in Sedum sarmentosum Bunge., S. lineare Thunb., and S. erythrostictum Migo. was developed, with a good linearity, precision, and stability. The detection wavelength was set at 500 nm, and an extraction solvent was optimized. Through the comparative study of multiple samples of the three plant drugs, their collected seasons and the habitats can be preliminarily ascertained, which may help to control the quality of the medicines to some extent.

  4. [Alterations in intraocular pressure and the CorVis parameters after LASIK].

    Science.gov (United States)

    Anton, A; Neuburger, M; Jordan, J F; Wecker, T; Lübke, J; Heinzelmann, S; Lapp, T; Böhringer, D; Reinhard, T; Maier, P

    2017-05-01

    The reduction of corneal thickness following laser-assisted in-situ keratomileusis (LASIK) requires a correction of intraocular pressure (IOP) measurements. The corneal visualization Scheimpflug technology (CorVis ST, Oculus, Wetzlar, Germany) not only measures the IOP and central corneal thickness (CCT) but also determines 10 additional corneal parameters, such as the time to first and second applanation and velocity. Besides CCT we compared various corneal parameters before and after LASIK in order to detect possible correlations and to correct IOP measurements. Measurements with CorVis ST were made before and after LASIK in 45 myopic patients (45 left eyes). We compared the IOP and CorVis ST parameters using a paired t‑test before and after LASIK and corrected for possible correlations in a multifactorial linear model. Finally, we correlated the changes in IOP to changes in biomechanical parameters. We observed a direct correlation between the IOP measurements and the corneal thickness. The IOP was underestimated by 0.039 mm Hg per micrometer in reduction of corneal thickness. The multifactorial linear model showed a correlation of IOP change to A2 velocity and the radius of applanation. Surgical thinning of the central cornea via LASIK demonstrated a direct correlation between corneal thickness and IOP measurements using the CorVis ST technique. Postoperative changes of the A2 velocity and the applanation radius also had a statistically significant influence on post-LASIK IOP measurements. Our findings could be useful to obtain more precise post-LASIK IOP measurements.

  5. QuVis interactive simulations: tools to support quantum mechanics instruction

    Science.gov (United States)

    Kohnle, Antje

    2015-04-01

    Quantum mechanics holds a fascination for many students, but its mathematical complexity and counterintuitive results can present major barriers. The QuVis Quantum Mechanics Visualization Project (www.st-andrews.ac.uk/physics/quvis) aims to overcome these issues through the development and evaluation of interactive simulations with accompanying activities for the learning and teaching of quantum mechanics. Over 90 simulations are now available on the QuVis website. One collection of simulations is embedded in the Institute of Physics Quantum Physics website (quantumphysics.iop.org), which consists of freely available resources for an introductory course in quantum mechanics starting from two-level systems. Simulations support model-building by reducing complexity, focusing on fundamental ideas and making the invisible visible. They promote engaged exploration, sense-making and linking of multiple representations, and include high levels of interactivity and direct feedback. Simulations are research-based and evaluation with students informs all stages of the development process. Simulations are iteratively refined using student feedback in individual observation sessions and in-class trials. Evaluation has shown that the simulations can help students learn quantum mechanics concepts at both the introductory and advanced undergraduate level and that students perceive simulations to be beneficial to their learning. Recent activity includes the launch of a new collection of HTML5 simulations that run on both desktop and tablet-based devices and the introduction of a goal and reward structure in simulations through the inclusion of challenges. This presentation will give an overview of the QuVis resources, highlight recent work and outline future plans. QuVis is supported by the UK Institute of Physics, the UK Higher Education Academy and the University of St Andrews.

  6. The UV-VIS spectrophotometry applied to color and stability study in colored mortars

    OpenAIRE

    Alejandre, F. J.

    1999-01-01

    In the field of methodologies for color studying, a research of it has been done on colored mortars by applying uv-vis spectrophotometry, instrumental technique which can be used for solid materials works, and previously applied to building materials study. Results obtained show that the mentioned technique permits to evaluate quantitatively and qualitatively colors in an easy and objective way, besides nowadays advantages of the instrumental analysis: digital color register, computerized dat...

  7. Merleau-Ponty, Lacan e Pessoa: o esfacelamento pulsional da visão

    Directory of Open Access Journals (Sweden)

    Maicon Reus Engler

    2015-06-01

    Full Text Available Este artigo mostra como alguns temas que Merleau-Ponty e Lacan mantêm em comum são tratados poeticamente na Ode Triunfal de Álvaro de Campos (Fernando Pessoa. Trata-se de uma tentativa de exemplificar como a literatura pode expressar a seu modo várias ideias e posições que a filosofia alcança de forma teórica. Apresentamos brevemente os conceitos de Ser Bruto e de Carne, introduzidos por Merleau-Ponty para evitar os dualismos seculares da filosofia. Além disso, esboçamos como ele, em sua obra tardia, discute o visível e o invisível no interior da mesma estratégia de reabilitação da sensibilidade que já encetara em seus primeiros escritos. Em seguida, mostramos como Lacan apropria-se de tais considerações para ressaltar a existência de uma visão, proveniente das coisas mesmas e prenhe de elementos pulsionais, que antecede o olhar do vidente. Para Lacan, o vidente sujeita-se com prazer sacrificial a tal visão e nela aniquila. Por fim, comentamos partes do poema de Pessoa em que se exemplificam os principais pontos em apreço.

  8. Robust drone detection for day/night counter-UAV with static VIS and SWIR cameras

    Science.gov (United States)

    Müller, Thomas

    2017-05-01

    Recent progress in the development of unmanned aerial vehicles (UAVs) has led to more and more situations in which drones like quadrocopters or octocopters pose a potential serious thread or could be used as a powerful tool for illegal activities. Therefore, counter-UAV systems are required in a lot of applications to detect approaching drones as early as possible. In this paper, an efficient and robust algorithm is presented for UAV detection using static VIS and SWIR cameras. Whereas VIS cameras with a high resolution enable to detect UAVs in the daytime in further distances, surveillance at night can be performed with a SWIR camera. First, a background estimation and structural adaptive change detection process detects movements and other changes in the observed scene. Afterwards, the local density of changes is computed used for background density learning and to build up the foreground model which are compared in order to finally get the UAV alarm result. The density model is used to filter out noise effects, on the one hand. On the other hand, moving scene parts like moving leaves in the wind or driving cars on a street can easily be learned in order to mask such areas out and suppress false alarms there. This scene learning is done automatically simply by processing without UAVs in order to capture the normal situation. The given results document the performance of the presented approach in VIS and SWIR in different situations.

  9. AppVis: Enabling data-rich apps in app inventor

    Science.gov (United States)

    Harunani, Farzeen

    MIT App Inventor has enabled middle school students to learn computing while creating their own apps--including apps that serve community needs. However, few resources exist for building apps that gather and share data. There is a need for new tools and an instructional materials for students to build data-enabled, community-focused apps. We developed an extension for App Inventor, called AppVis, which allows app-makers to publish and retrieve data from iSENSE, our existing web-based collaborative data visualization platform. We used AppVis and supporting instructional materials in two one-week summer camps attended by a total of 33 middle school students. Based on student interview data and analysis of their final apps, our approach was broadly accessible to a diverse population of students. Students were motivated to build apps that could be used by their own communities. This thesis presents the design of AppVis and results from students' work in summer camps.

  10. Screening of oil sands naphthenic acids by UV-Vis absorption and fluorescence emission spectrophotometry.

    Science.gov (United States)

    Mohamed, Mohamed H; Wilson, Lee D; Headley, John V; Peru, Kerry M

    2008-12-01

    Oil sands extracted naphthenic acids fractions are known to contain impurities with various levels of unsaturation and aromaticity. These constituents contain functional groups that absorb ultraviolet-visible wavelength (UV-Vis) radiation and give intense fluorescence emission in contrast to the fully saturated alicyclic naphthenic acids. UV-Vis absorption and fluorescence emission spectrophotometry are presented here as inexpensive and quick screening methods that the detection of chromophoric surrogate compounds that serve as an internal standard for the indirect analysis of oil sands naphthenic acids. The method detection limit for the screening techniques was approximately 1 mg/L with an observed linear range of 1-100 mg/L. The precision of measurements was generally within 10% r.s.d. There was generally good agreement (within 20% r.s.d) for isotherm parameters from non-linear fitting of Langmuir, BET and Freundlich models for sorption of Athabasca oil sands naphthenic acid mixtures to activated carbon samples determined by UV-Vis absorption, fluorescence emission spectroscopy, and conventional direct injection electrospray ionization mass spectrometry.

  11. Artificial neural network associated to UV/Vis spectroscopy for monitoring bioreactions in biopharmaceutical processes.

    Science.gov (United States)

    Takahashi, Maria Beatriz; Leme, Jaci; Caricati, Celso Pereira; Tonso, Aldo; Fernández Núñez, Eutimio Gustavo; Rocha, José Celso

    2015-06-01

    Currently, mammalian cells are the most utilized hosts for biopharmaceutical production. The culture media for these cell lines include commonly in their composition a pH indicator. Spectroscopic techniques are used for biopharmaceutical process monitoring, among them, UV-Vis spectroscopy has found scarce applications. This work aimed to define artificial neural networks architecture and fit its parameters to predict some nutrients and metabolites, as well as viable cell concentration based on UV-Vis spectral data of mammalian cell bioprocess using phenol red in culture medium. The BHK-21 cell line was used as a mammalian cell model. Off-line spectra of supernatant samples taken from batches performed at different dissolved oxygen concentrations in two bioreactor configurations and with two pH control strategies were used to define two artificial neural networks. According to absolute errors, glutamine (0.13 ± 0.14 mM), glutamate (0.02 ± 0.02 mM), glucose (1.11 ± 1.70 mM), lactate (0.84 ± 0.68 mM) and viable cell concentrations (1.89 10(5) ± 1.90 10(5) cell/mL) were suitably predicted. The prediction error averages for monitored variables were lower than those previously reported using different spectroscopic techniques in combination with partial least squares or artificial neural network. The present work allows for UV-VIS sensor development, and decreases cost related to nutrients and metabolite quantifications.

  12. UV-Vis Ratiometric Resonance Synchronous Spectroscopy for Determination of Nanoparticle and Molecular Optical Cross Sections.

    Science.gov (United States)

    Nettles, Charles B; Zhou, Yadong; Zou, Shengli; Zhang, Dongmao

    2016-03-01

    Demonstrated herein is a UV-vis Ratiometric Resonance Synchronous Spectroscopic (R2S2, pronounced as "R-two-S-two" for simplicity) technique where the R2S2 spectrum is obtained by dividing the resonance synchronous spectrum of a NP-containing solution by the solvent resonance synchronous spectrum. Combined with conventional UV-vis measurements, this R2S2 method enables experimental quantification of the absolute optical cross sections for a wide range of molecular and nanoparticle (NP) materials that range optically from pure photon absorbers or scatterers to simultaneous photon absorbers and scatterers, simultaneous photon absorbers and emitters, and all the way to simultaneous photon absorbers, scatterers, and emitters in the UV-vis wavelength region. Example applications of this R2S2 method were demonstrated for quantifying the Rayleigh scattering cross sections of solvents including water and toluene, absorption and resonance light scattering cross sections for plasmonic gold nanoparticles, and absorption, scattering, and on-resonance fluorescence cross sections for semiconductor quantum dots (Qdots). On-resonance fluorescence quantum yields were quantified for the model molecular fluorophore Eosin Y and fluorescent Qdots CdSe and CdSe/ZnS. The insights and methodology presented in this work should be of broad significance in physical and biological science research that involves photon/matter interactions.

  13. Detection Limits of DLS and UV-Vis Spectroscopy in Characterization of Polydisperse Nanoparticles Colloids

    Directory of Open Access Journals (Sweden)

    Emilia Tomaszewska

    2013-01-01

    Full Text Available Dynamic light scattering is a method that depends on the interaction of light with particles. This method can be used for measurements of narrow particle size distributions especially in the range of 2–500 nm. Sample polydispersity can distort the results, and we could not see the real populations of particles because big particles presented in the sample can screen smaller ones. Although the theory and mathematical basics of DLS technique are already well known, little has been done to determine its limits experimentally. The size and size distribution of artificially prepared polydisperse silver nanoparticles (NPs colloids were studied using dynamic light scattering (DLS and ultraviolet-visible (UV-Vis spectroscopy. Polydisperse colloids were prepared based on the mixture of chemically synthesized monodisperse colloids well characterized by atomic force microscopy (AFM, transmission electron microscopy (TEM, DLS, and UV-Vis spectroscopy. Analysis of the DLS results obtained for polydisperse colloids reveals that several percent of the volume content of bigger NPs could screen completely the presence of smaller ones. The presented results could be extremely important from nanoparticles metrology point of view and should help to understand experimental data especially for the one who works with DLS and/or UV-Vis only.

  14. Online measurement of contents in compound fertilizer and application research using VIS-NIR spectroscopy

    Science.gov (United States)

    Lin, Zhidan; Wang, Yubing; Wang, Rujing; Liu, Jing; Lu, Cuiping; Wang, Liusan

    2015-10-01

    The on-line measurement of the main component contents is essential for production, detection and identification of compound fertilizer. Using developed VIS-NIR sensors for on-line measurement of the main component contents in compound fertilizer, primary results about nitrogen (N), phosphorus pentoxide (P2O5) and potassium oxide (K2O) were reported. A visible (VIS) and near infrared (NIR) spectrophotometer (Ocean Optics), with a measurement range of 360.18-2221.53 nm was used to measure fertilizer spectra in reflectance mode. By using principal component analysis (PCA) and mahalanobis distance method, 3 outlier samples were detected and eliminated from 174 samples firstly. Then these models of three components with the 124 samples in calibration set were established using principal component regress (PCR) and partial least squares regression (PLS) coupled respectively with the full cross-validation technique after preprocessing the original spectrum with different methods. These models were used to estimate the contents of N, P2O5 and K2O of the other 47 samples in predicted set. The research results showed that the method could be applied to rapid measurement to the main component contents in compound fertilizer. Compared with the traditional analysis method, the on-line measurement could do it rapidly, inexpensively and pollution-freely. It suggested the potential use of the VIS-NIR sensing system for on-line measurement in the production, detection and identification process of compound fertilizer.

  15. Speculative Practices: Utilizing InfoVis to Explore Untapped Literary Collections.

    Science.gov (United States)

    Hinrichs, Uta; Forlini, Stefania; Moynihan, Bridget

    2016-01-01

    In this paper we exemplify how information visualization supports speculative thinking, hypotheses testing, and preliminary interpretation processes as part of literary research. While InfoVis has become a buzz topic in the digital humanities, skepticism remains about how effectively it integrates into and expands on traditional humanities research approaches. From an InfoVis perspective, we lack case studies that show the specific design challenges that make literary studies and humanities research at large a unique application area for information visualization. We examine these questions through our case study of the Speculative W@nderverse, a visualization tool that was designed to enable the analysis and exploration of an untapped literary collection consisting of thousands of science fiction short stories. We present the results of two empirical studies that involved general-interest readers and literary scholars who used the evolving visualization prototype as part of their research for over a year. Our findings suggest a design space for visualizing literary collections that is defined by (1) their academic and public relevance, (2) the tension between qualitative vs. quantitative methods of interpretation, (3) result- vs. process-driven approaches to InfoVis, and (4) the unique material and visual qualities of cultural collections. Through the Speculative W@nderverse we demonstrate how visualization can bridge these sometimes contradictory perspectives by cultivating curiosity and providing entry points into literary collections while, at the same time, supporting multiple aspects of humanities research processes.

  16. Miniaturization of environmental chemical assays in flowing systems: The lab-on-a-valve approach vis-a-vis lab-on-a-chip microfluidic devices

    Energy Technology Data Exchange (ETDEWEB)

    Miro, Manuel [Department of Chemistry, Faculty of Sciences, University of the Balearic Islands, Carretera de Valldemossa, km. 7.5, E-07122-Palma de Mallorca, Illes Balears (Spain)], E-mail: manuel.miro@uib.es; Hansen, Elo Harald [Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, DK-2800 Kgs. Lyngby (Denmark)

    2007-09-26

    The analytical capabilities of the microminiaturized lab-on-a-valve (LOV) module integrated into a microsequential injection ({mu}SI) fluidic system in terms of analytical chemical performance, microfluidic handling and on-line sample processing are compared to those of the micro total analysis systems ({mu}TAS), also termed lab-on-a-chip (LOC). This paper illustrates, via selected representative examples, the potentials of the LOV scheme vis-a-vis LOC microdevices for environmental assays. By means of user-friendly programmable flow and the exploitation of the interplay between the thermodynamics and the kinetics of the chemical reactions at will, LOV allows accommodation of reactions which, at least at the present stage, are not feasible by application of microfluidic LOC systems. Thus, in LOV one may take full advantage of kinetic discriminations schemes, where even subtle differences in reactions are utilized for analytical purposes. Furthermore, it is also feasible to handle multi-step sequential reactions of divergent kinetics; to conduct multi-parametric determinations without manifold reconfiguration by utilization of the inherent open-architecture of the micromachined unit for implementation of peripheral modules and automated handling of a variety of reagents; and most importantly, it offers itself as a versatile front end to a plethora of detection schemes. Not the least, LOV is regarded as an emerging downscaled tool to overcome the dilemma of LOC microsystems to admit real-life samples. This is nurtured via its intrinsic flexibility for accommodation of sample pre-treatment schemes aimed at the on-line manipulation of complex samples. Thus, LOV is playing a prominent role in the environmental field, whenever the monitoring of trace level concentration of pollutants is pursued, because both matrix isolation and preconcentration of target analytes is most often imperative, or in fact necessary, prior to sample presentation to the detector.

  17. Should the Red Dragon arise? Assessing China's options vis-à-vis the enactment of a domestic space resources utilization law

    Science.gov (United States)

    Hao, L.; Tronchetti, F.

    2017-05-01

    The past couple of years have witnesses one of the most exciting, yet controversial, developments in the field of space law, namely the adoption of domestic laws authorizing the (private) appropriation and utilization of outer space resources. Even though the technology to effectively mine resources in outer space is still under development countries like the United States and Luxembourg have taken this legislative step as a mean to promote the growth of a domestic private space mining sector. The enactment of national space resources utilization laws has generated extensive interest both within academic circles and official fora, such as the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS). In this context, several countries have expressed their opinion about these initiatives, by often criticizing their legality vis-a-vis international space law. Despite this remarkable level of interest there is a country that throughout this process has maintained a low profile, namely China. Indeed, China has neither reacted to the US and Luxembourgish moves nor has officially commented on the lawfulness of domestic space mining laws. This conduct is particularly relevant not only in the light of the growing importance of the Chinese space program but also if one considers that China is the country most involved in the exploration and study of celestial bodies and their resources, particularly the Moon. For this reasons it would have been legitimate to expect China to have a more engaged behavior. However, China has acted otherwise. It seems thus worth evaluating whether China should maintain this 'wait and see' approach or should instead switch towards a more assertive position, both internationally and domestically, especially one which includes the adoption of a space resources utilization act.

  18. [Using UV-Vis Absorbance for Characterization of Maturity in Composting Process with Different Materials].

    Science.gov (United States)

    Zhao, Yue; Wei, Yu-quan; Li, Yang; Xi, Bei-dou; Wei, Zi-min; Wang, Xing-lei; Zhao, Zhi-nan; Ding, Jei

    2015-04-01

    The present study was conducted to assess the degree of humification in DOM during composting using different raw materials, and their effect on maturity of compost based on UV-Vis spectra measurements and chemometrics method. The raw materials of composting studied included chicken manure, pig manure, kitchen waste, lawn waste, fruits and vegetables waste, straw waste, green waste, sludge, and municipal solid waste. During composting, the parameters of UV-Vis spectra of DOM, including SUVA254 , SUVA280 , E250/E365, E4/E6, E2/E4, E2/E6, E253/E203, E253/E220, A226-400, S275-295 and S350-400 were calculated, Statistical analysis indicated that all the parameter were significantly changed during composting. SUVA254 and SUVA280 of DOM were continuously increased, E250/E365 and E4/E6 were continuously decreased in DOM, while A226-400, S275-295 and S350-400 of DOM at the final stage were significantly different with those at other stages of composting. Correlation analysis indicated that the parameters were significantly correlated with each other except for E2/E4 and E235/E203. Furthermore, principal component analysis suggested that A226-400, SUVA254, S350-400, SUVA280 and S275~295 were reasonable parameters for assessing the compost maturity. To distinguish maturity degree among different composts, hierarchical cluster analysis, an integrated tool utilizing multiple UV-Vis parameters, was performed based on the data (A226-400, SUVA254, S350-400, SUVA280 and S275-295) of DOM derived from the final stage of composting. Composts from different sources were clustered into 2 groups. The first group included chicken manure, pig manure, lawn waste, fruits and vegetables waste, green waste, sludge, and municipal solid waste characterized by a lower maturity degree, and the second group contained straw waste and kitchen waste associated with a higher maturity degree. The above results suggest that a multi-index of UV-Vis spectra could accurately evaluate the compost maturity

  19. Fisiologia da visão binocular Physiology of binocular vision

    Directory of Open Access Journals (Sweden)

    Harley E. A. Bicas

    2004-02-01

    Full Text Available A visão binocular de seres humanos resulta da superposição quase completa dos campos visuais de cada olho, o que suscita discriminação perceptual de localizações espaciais de objetos relativamente ao observador (localização egocêntrica bem mais fina (estereopsia, mas isso ocorre em, apenas, uma faixa muito estreita (o horóptero. Aquém e além dela, acham-se presentes diplopia e confusão, sendo necessária supressão fisiológica (cortical para evitá-las. Analisa-se a geometria do horóptero e suas implicações fisiológicas (o desvio de Hillebrand, a partição de Kundt, a área de Panum, assim como aspectos clínicos da visão binocular normal (percepção simultânea, fusão, visão estereoscópica e de adaptações a seus estados afetados (supressão patológica, ambliopia, correspondência visual anômala.The binocular vision of human beings is given by the almost complete superimposition of the monocular visual fields, which allows a finer perceptual discrimination of the egocentric localization of objects in space (stereopsis but only within a very narrow band (the horopter. Before and beyond it, diplopia and confusion are present, so that a physiologic (cortical suppression is necessary to avoid them to become conscious. The geometry of the horopter and its physiologic implications (Hillebrand's deviation, Kundt's partition, Panum's area, stereoscopic vision are analyzed, as well as some clinical aspects of the normal binocular vision (simultaneous perception, fusion, stereoscopic vision and of adaptations to abnormal states (pathologic suppression, amblyopia, abnormal retinal correspondence.

  20. Discrimination of Apple Liqueurs (Nalewka) Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy.

    Science.gov (United States)

    Śliwińska, Magdalena; Garcia-Hernandez, Celia; Kościński, Mikołaj; Dymerski, Tomasz; Wardencki, Waldemar; Namieśnik, Jacek; Śliwińska-Bartkowiak, Małgorzata; Jurga, Stefan; Garcia-Cabezon, Cristina; Rodriguez-Mendez, Maria Luz

    2016-10-09

    The capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different apple varieties is achieved using the e-tongue and UV-Vis spectroscopy. Raman spectra coupled to chemometrics have not been efficient in discriminating liqueurs. The calculated Euclidean distances and the k-Nearest Neighbors algorithm (kNN) confirmed these results. The main advantage of the e-tongue is that, using PLS-1, good correlations have been found simultaneously with the phenolic content measured by the Folin-Ciocalteu method (R² of 0.97 in calibration and R² of 0.93 in validation) and also with the density, a marker of the alcoholic content method (R² of 0.93 in calibration and R² of 0.88 in validation). UV-Vis coupled with chemometrics has shown good correlations only with the phenolic content (R² of 0.99 in calibration and R² of 0.99 in validation) but correlations with the alcoholic content were low. Raman coupled with chemometrics has shown good correlations only with density (R² of 0.96 in calibration and R² of 0.85 in validation). In summary, from the three holistic methods evaluated to analyze strong alcoholic liqueurs, the voltammetric electronic tongue using phthalocyanines as sensing elements is superior to Raman or UV-Vis techniques because it shows an excellent discrimination capability and remarkable correlations with both antioxidant capacity and alcoholic content-the most important parameters to be measured in this type of liqueurs.

  1. Fingerprinting Food Supplements and Their Botanical Ingredients by Coupled UV/Vis/FTIR Spectrometry

    Directory of Open Access Journals (Sweden)

    Anca Baciu

    2013-11-01

    Full Text Available Medicinal plants are used as ingredients for a large variety of herbal supplements. Their quality and safety versus efficacy, according to present legal requirements, need to meet the minimum quality criteria to support their use. Specific biomarkers to evaluate and screen their authenticity are phenolic derivatives, phtosterols, lipids or alkaloids. We report here the data obtained  for  two herbal food supplements (A and B obtained from  different mixtures of plants: Taraxacum officinalis, Cynara scolimus Silybum marianum as ingredients for product A  and Hypericum perforatum, Chelidonium majus and Lycopodium clavatum as ingredients for product B. The combination of UV-Vis and FTIR spectrometry allowed a specific fingerprint of biomarkers in individual plants and derived supplements ( A and B, by discriminating the specific areas and peaks of individual plants and  mixtures, the significant differences between the methanolic and water extracts. The data were compared using chemometry ( PCA and Cluster analysis. Using Vis spectrometry combined with FTIR  peak intensities at 1732 cm-1 and calibration with gallic acid,  the total phenolics concentrations ranged from 5.31 to 9.58 mg gallic acid eq/ml methanol, with a positive and significant correlation between the two methods (R2= 0.979. The phenolics’ concentration were 2.5 to 4 times lower in water extracts comparing with methanol extracts of  products A and B.  Finally, we assume that herbal supplements can be adequately characterized for their quality and safety by combined UV-Vis spectrometry/FTIR spectrometry, with good, fast and cheap informations about the main biomarkers of authenticity.

  2. Inferring DOC export mechanisms from high-frequency, instream UV-VIS concentration measurements

    Science.gov (United States)

    Oosterwoud, Marieke; Musolff, Andreas; Keller, Toralf; Fleckenstein, Jan

    2015-04-01

    The flux of soil-derived dissolved organic carbon (DOC) is a significant term in terrestrial carbon budgets and, as a result, a dominant link between terrestrial and aquatic ecosystems. Concentrations of dissolved organic carbon in streams and rivers have been increasing in many parts of the world. Providers of drinking water from surface water reservoirs are increasingly facing problems as elevated DOC concentrations cause higher costs for removal and potentially to toxic by-products during chlorination. Mitigating these problems requires a mechanistic understanding of the controls and dynamics of DOC export from catchments. High frequency measurements using UV-vis absorbance as a proxy for DOC concentrations allow for improved evaluation of DOC concentration-discharge relationships in catchments. In addition, several UV-vis absorbance proxies (both single and multiple wavelength) can be used as an indicator of DOC quality. These relationships allow quantification of net DOC export, and may additionally provide new insights into the mechanisms that control DOC export dynamics. We aimed to evaluate the response and interaction of DOC concentrations and quality between a riparian zone soil and stream under different hydrological conditions. UV-vis sensors were installed in both the riparian soil and stream of two headwater catchments, the Hassel and Rappbode, in the Harz Mountains in Germany. The two headwater catchments are approximately equal in size, however, differ in their land-use. The Hassel catchment is dominated by agricultural land-use, whereas the Rappbode catchment is mainly forested. The DOC concentration-discharge relationships show intricate hysteretic behavior, which differs between locations and shifts in time. The rich data-set will allow for a characterization of space and time patterns of DOC export as well as changes in its quality, providing valuable new insights into the hydrologic mechanisms that govern the delivery of DOC to streams.

  3. Discrimination of Apple Liqueurs (Nalewka Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Magdalena Śliwińska

    2016-10-01

    Full Text Available The capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different apple varieties is achieved using the e-tongue and UV-Vis spectroscopy. Raman spectra coupled to chemometrics have not been efficient in discriminating liqueurs. The calculated Euclidean distances and the k-Nearest Neighbors algorithm (kNN confirmed these results. The main advantage of the e-tongue is that, using PLS-1, good correlations have been found simultaneously with the phenolic content measured by the Folin–Ciocalteu method (R2 of 0.97 in calibration and R2 of 0.93 in validation and also with the density, a marker of the alcoholic content method (R2 of 0.93 in calibration and R2 of 0.88 in validation. UV-Vis coupled with chemometrics has shown good correlations only with the phenolic content (R2 of 0.99 in calibration and R2 of 0.99 in validation but correlations with the alcoholic content were low. Raman coupled with chemometrics has shown good correlations only with density (R2 of 0.96 in calibration and R2 of 0.85 in validation. In summary, from the three holistic methods evaluated to analyze strong alcoholic liqueurs, the voltammetric electronic tongue using phthalocyanines as sensing elements is superior to Raman or UV-Vis techniques because it shows an excellent discrimination capability and remarkable correlations with both antioxidant capacity and alcoholic content—the most important parameters to be measured in this type of liqueurs.

  4. The VIS-AD data model: Integrating metadata and polymorphic display with a scientific programming language

    Science.gov (United States)

    Hibbard, William L.; Dyer, Charles R.; Paul, Brian E.

    1994-01-01

    The VIS-AD data model integrates metadata about the precision of values, including missing data indicators and the way that arrays sample continuous functions, with the data objects of a scientific programming language. The data objects of this data model form a lattice, ordered by the precision with which they approximate mathematical objects. We define a similar lattice of displays and study visualization processes as functions from data lattices to display lattices. Such functions can be applied to visualize data objects of all data types and are thus polymorphic.

  5. Prescrição medicamentosa sob a visão de estudantes de Odontologia

    OpenAIRE

    Lúcio, Priscilla Suassuna Carneiro; Castro, Ricardo Dias de; Barreto, Rosimar de Castro

    2016-01-01

    Objetivo: Analisar, entre os acadêmicos de odontologia de duas universidades públicas da Paraíba, a visão que os mesmos tinham a respeito da prescrição de medicamentos, assim como verificar se os conhecimentos adquiridos na graduação são suficientes para o desempenho de uma correta e seguraprescrição medicamentosa. Materiais e Métodos: A amostra foi definida por conveniência, correspondendo a 132 alunos matriculados na Universidade Federal da Paraíba (UFPB) e Universidade Estadual da Paraíba ...

  6. Estratégias da ordem global: visões distintas num mundo globalizado

    OpenAIRE

    Daehnhardt, Patrícia

    2011-01-01

    No mundo do pós-Guerra Fria, que é simultaneamente um mundo de desordem e um mundo de visões confl itantes de ordem internacional, grandes potências estabelecidas e potências emergentes interagem para afi rmar-se no seu ambiente regional, nas instituições internacionais e no sistema internacional. Enquanto a maioria desses poderes se esforça para assegurar a estabilidade e a ordem internacional, nas interações entre eles fricções ocorrem inevitavelmente e produzem o potencial d...

  7. UV-vis spectroscopy for on-line monitoring of Au nanoparticles size during growth

    Energy Technology Data Exchange (ETDEWEB)

    Salvati, R. [Istituto per i Materiali Compositi e Biomedici-Consiglio Nazionale delle Ricerche, Piazzale Tecchio 80, 80125 Naples (Italy); Longo, A. [Istituto per i Materiali Compositi e Biomedici-Consiglio Nazionale delle Ricerche, Piazzale Tecchio 80, 80125 Naples (Italy); Carotenuto, G. [Istituto per i Materiali Compositi e Biomedici-Consiglio Nazionale delle Ricerche, Piazzale Tecchio 80, 80125 Naples (Italy); De Nicola, S. [Istituto di Cibernetica-Consiglio Nazionale delle Ricerche ' E Caianiello' , Via Campi Flegrei 34, 80078 Pozzuoli (Italy); Pepe, G.P. [Coherentia INFM, Universita di Napoli ' Federico II' -Dipartimento Scienze Fisiche, Fac. Ingegneria, P.le Tecchio n. 80, I-80125 Naples (Italy); Nicolais, L. [Istituto per i Materiali Compositi e Biomedici-Consiglio Nazionale delle Ricerche, Piazzale Tecchio 80, 80125 Naples (Italy); Barone, A. [Coherentia INFM, Universita di Napoli ' Federico II' -Dipartimento Scienze Fisiche, Fac. Ingegneria, P.le Tecchio n. 80, I-80125 Naples (Italy)

    2005-07-30

    Gold nanoparticles have been prepared by alcoholic reduction of Au(III) ions in presence of a polymeric stabilizer (poly(N-vinyl pyrrolidone), PVP). On-line UV-vis spectroscopic characterization and transmission electron microscopy (TEM) analysis are presented. Optical spectroscopy data show that the temporal evolution of absorption spectra and the absorbance peak properties are correlated to the off-line size measurements obtained at chemical reaction end by TEM micrographs. The Au cluster size behaves linearly with time above a threshold temperature (70 deg. C), according to a deposition-controlled growth mechanism.

  8. A quality control technique based on UV-VIS absorption spectroscopy for tequila distillery factories

    Science.gov (United States)

    Barbosa Garcia, O.; Ramos Ortiz, G.; Maldonado, J. L.; Pichardo Molina, J.; Meneses Nava, M. A.; Landgrave, Enrique; Cervantes, M. J.

    2006-02-01

    A low cost technique based on the UV-VIS absorption spectroscopy is presented for the quality control of the spirit drink known as tequila. It is shown that such spectra offer enough information to discriminate a given spirit drink from a group of bottled commercial tequilas. The technique was applied to white tequilas. Contrary to the reference analytic methods, such as chromatography, for this technique neither special personal training nor sophisticated instrumentations is required. By using hand-held instrumentation this technique can be applied in situ during the production process.

  9. [UV-Vis spectroscopic characterization of active components from Scutellaria baicalensis georgi].

    Science.gov (United States)

    Li, Yun-xia; Suo, Quan-ling; He, Wen-zhi; Li, Chun-ping; Huang, Yan-chun

    2007-01-01

    The molecular structures of three active components from scutellaria baicalensis have been studied by ultraviolet-visible spectra. The index flavonoid structures and substituted positions were deduced by analyzing the UV-Vis spectra in the methanol solution of three active components and the methanol solution with 5 diagnostic reagents, NaOMe, NaOAc, NaOAc/H3BO3, AlCl3, AlCl3/HCl respectively, which provided strong evidences for the structural characterization of the active components from natural products.

  10. Diabo versus salvação na visão de Túndalo

    Directory of Open Access Journals (Sweden)

    Adriana Maria de Souza Zierer

    2010-01-01

    Full Text Available Visio Tnugdali is an exemplum, a moral narrative with the task of convincing an audience for the purpose of conversion. Produced in the in twelfth century by an unknown Cistercian monk, it was translated to Portuguese in the fifteenth century (Visão de Túndalo. Through the image of the devil and of the torments in hell, the Christians would repent their sins and search for salvation, adopting the behavior indicated by the Catholic Church to conduct them to Paradise.

  11. Interação Humano - Computador usando Visão Computacional

    Directory of Open Access Journals (Sweden)

    Bernardo Bucher B. Barbosa

    2015-07-01

    Full Text Available Este trabalho visa estudar maneiras de se explorar a Interação Humano Computador, usando Visão Computacional. A idéia tem como objetivo um esforço para tornar o computador mais interativo com o usuário, sem a necessidade da compra de um hardware ou acessório específico para tal. O produto final deste trabalho em desenvolvimento é um software que contempla esta funcionalidade, tornando o computador mais interativo.

  12. SWIR, VIS and LWIR observer performance against handheld objects: a comparison

    Science.gov (United States)

    Adomeit, Uwe

    2016-10-01

    The short wave infrared spectral range caused interest to be used in day and night time military and security applications in the last years. This necessitates performance assessment of SWIR imaging equipment in comparison to the one operating in the visual (VIS) and thermal infrared (LWIR) spectral range. In the military context (nominal) range is the main performance criteria. Discriminating friend from foe is one of the main tasks in today's asymmetric scenarios and so personnel, human activities and handheld objects are used as targets to estimate ranges. The later was also used for an experiment at Fraunhofer IOSB to get a first impression how the SWIR performs compared to VIS and LWIR. A human consecutively carrying one of nine different civil or military objects was recorded from five different ranges in the three spectral ranges. For the visual spectral range a 3-chip color-camera was used, the SWIR range was covered by an InGaAs-camera and the LWIR by an uncooled bolometer. It was ascertained that the nominal spatial resolution of the three cameras was in the same magnitude in order to enable an unbiased assessment. Daytime conditions were selected for data acquisition to separate the observer performance from illumination conditions and to some extend also camera performance. From the recorded data, a perception experiment was prepared. It was conducted as a nine-alternative forced choice, unlimited observation time test with 15 observers participating. Before the experiment, the observers were trained on close range target data. Outcome of the experiment was the average probability of identification versus range between camera and target. The comparison of the range performance achieved in the three spectral bands gave a mixed result. On one hand a ranking VIS / SWIR / LWIR in decreasing order can be seen in the data, but on the other hand only the difference between VIS and the other bands is statistically significant. Additionally it was not possible

  13. UV–VIS and HPLC studies on Amphiroa anceps (Lamarck Decaisne

    Directory of Open Access Journals (Sweden)

    Johnson Marimuthu (a Antonisamy

    2016-09-01

    Full Text Available The present study was aimed to explore phytochemical constituents present in Amphiroa anceps (Lamarck Decaisne. The extracts of A. anceps were scanned in the wavelength ranging from 200 to 1100 nm by using Shimadzu Spectrophotometer. HPLC method was performed on a Shimadzu LC-10 AT VP HPLC system, which was equipped with a model LC-10AT pump, UV–VIS detector SPD-10AT, Rheodyne injector fitted with a 20 μl loop and auto injector SIL-10AT. Out of 156 (2 × 6 × 13 = 156 tests for the presence or absence of the above compounds, 42 tests gave positive results and the remaining 114 showed negative results. The 42 positive results showed the presence of alkaloids, steroids, phenolic groups, saponins, tannin, flavonoids, terpenoids, glycosides, proteins and sugars. The results of the ash analysis discovered the existence of sulphur, calcium, magnesium, iron, phosphorous and chlorine in all the extracts of A. anceps. The UV–VIS profile of A. anceps benzene extracts showed peaks at 670, 612, 536, 504, and 412 nm with the absorption 2.004, 0.333, 0.417, 0.608 and 3.311. The UV–VIS profile of A. anceps chloroform extracts showed the peaks at 666, 608, 538, 502 and 416 nm with the absorption 1.029, 0.39, 0.458, 0.552 and 2.648. The qualitative UV–VIS spectrum profile of A. anceps methanolic extracts showed peaks at 656 and 330 nm with the absorption 0.295 and 3.656. The HPLC profile of A. anceps aqueous extracts showed two prominent peaks at a retention time of 1.737 and 2.680 min and some moderate peaks were observed with the retention time 4.083, 6.387 and 1.490 min. The qualitative HPLC fingerprint profile of isopropanol extract of A. anceps showed one prominent peak at a retention time of 2.673 min. The HPLC profile of A. anceps methanolic extracts illustrated two prominent peaks at a retention time of 1.927 and 2.667 min and some moderate peaks were also observed with the retention time 2.347, 4.077 and 5.873 min, respectively.

  14. [On-site evaluation of raw milk qualities by portable Vis/NIR transmittance technique].

    Science.gov (United States)

    Wang, Jia-Hua; Zhang, Xiao-Wei; Wang, Jun; Han, Dong-Hai

    2014-10-01

    To ensure the material safety of dairy products, visible (Vis)/near infrared (NIR) spectroscopy combined with che- mometrics methods was used to develop models for fat, protein, dry matter (DM) and lactose on-site evaluation. A total of 88 raw milk samples were collected from individual livestocks in different years. The spectral of raw milk were measured by a porta- ble Vis/NIR spectrometer with diffused transmittance accessory. To remove the scatter effect and baseline drift, the diffused transmittance spectra were preprocessed by 2nd order derivative with Savitsky-Golay (polynomial order 2, data point 25). Changeable size moving window partial least squares (CSMWPLS) and genetic algorithms partial least squares (GAPLS) meth- ods were suggested to select informative regions for PLS calibration. The PLS and multiple linear regression (MLR) methods were used to develop models for predicting quality index of raw milk. The prediction performance of CSMWPLS models were similar to GAPLS models for fat, protein, DM and lactose evaluation, the root mean standard errors of prediction (RMSEP) were 0.115 6/0.103 3, 0.096 2/0.113 7, 0.201 3/0.123 7 and 0.077 4/0.066 8, and the relative standard deviations of prediction (RPD) were 8.99/10.06, 3.53/2.99, 5.76/9.38 and 1.81/2.10, respectively. Meanwhile, the MLR models were also cal- ibrated with 8, 10, 9 and 7 variables for fat, protein, DM and lactose, respectively. The prediction performance of MLR models was better than or close to PLS models. The MLR models to predict fat, protein, DM and lactose yielded the RMSEP of 0.107 0, 0.093 0, 0.136 0 and 0.065 8, and the RPD of 9.72, 3.66, 8.53 and 2.13, respectively. The results demonstrated the usefulness of Vis/NIR spectra combined with multivariate calibration methods as an objective and rapid method for the quality evaluation of complicated raw milks. And the results obtained also highlight the potential of portable Vis/NIR instruments for on-site assessing quality indexes of

  15. A flow-batch analyzer for UV-Vis spectrophotometric detection of adulteration in distilled spirits

    OpenAIRE

    Nascimento, Elaine C.L.; Araújo, Mário C. U.; Galvão,Roberto K. H.

    2011-01-01

    An automatic flow-batch analyzer is proposed for detection of adulteration in distilled spirits (whiskey, brandy, cachaça, rum and vodka) using UV-Vis spectrophotometry. The analyzer was employed to dilute the non-adulterated samples and to simulate adulteration with addition of 5 and 10% (v/v) of water, ethanol or methanol. SIMCA (soft independent modelling of class analogies) classification models were built using spectra of non-adulterated and adulterated samples in the region of 235-355 n...

  16. Visâlî Ali Çelebi ve Mevlid’i Visâlî Ali Çelebi And His Mevlid

    Directory of Open Access Journals (Sweden)

    Abdülmecit İSLAMOĞLU

    2013-03-01

    Full Text Available Visali Ali Çelebi is one of the XVIth century poets. On the basis of the poet’s work, limited information of his life can be reached. Of this kind of information is that Visali’s name was Ali and hi lived in the time of Suleiman the Magnificent. Poet’s work entitled “Mevlid-i Fahr-i Kâ’inât Muhammedini’l-Mustafâ” is a work composed in the form of mawlid that dealt with the birth of the Prophet, his childhood until seven years of age and some miracles taking place in this period. The only known manuscript copy of Visali Mevlidi is recorded in Türk Dil Kurumu Kütüphanesi, manuscript A/99 numbered. Though the mawlidmost of which was written in the masnawi form of verse, in order toavoid monotony and catch the attention of readers, the verses in theform of qasida/gazel were interspersed throughout text. In the work,intensely, Fâ‘ilâtün Fâ‘ilâtün Fâ‘ilün aruz prosody was used. In theparts written in verse, the language becomes more difficult. It can besaid that in the parts written in the form of masnawi, a plainer lenguageis used. Nevertheless, Arabic-Persian words and phrases are also seenin the Masnawis. In the Mawlid, there also existed completely Arabic orPersian verses. Considering these features, poet’s style and his power inthe field of poetry, it can be said that the work is not simple and fluent.The fat that Mawlid was suddenly finished in the childhood period ofthe Prophet gives the impression that the works was left half finished.However, when the work is compared with other texts written in theform of mawlid, with 1715 verses, it can be categorized among thevoluminous works. In this article, after giving some information aboutthe form and contents of Visali Ali Çelebi’s Mawlid, the transliteratedtext of the only copy of work we could find so far has been presented. Visâlî Ali Çelebi XVI. yüzyıl şairlerindendir. Şairin bilinen tek eseri olan Mevlid’inden yola çıkılarak adının Ali oldu

  17. A competitividade das universidades particulares à luz de uma visão baseada em recursos.

    Directory of Open Access Journals (Sweden)

    Vânia Maria Jorge Nassif

    2002-06-01

    Full Text Available A visão baseada em recursos defende que os recursos da organização constituem-se no principal determinante de vantagem competitiva sustentável. Assim, o objetivo da pesquisa é identificar as competências requeridas de docentes universitários de universidades privadas do Estado de São Paulo, como elemento primordial para elevar a competitividade destas instituições. As pesquisas qualitativa e quantitativa revelaram que a competência dos docentes não se evidencia como fator de competitividade. Os investimentos em infra-estrutura e preço de mensalidade constituem-se em uma vantagem competitiva. Esta visão é coerente com o papel operacional da área de RH destas instituições, que não desempenha ações para desenvolver as competências identificadas na pesquisa. A contratação de docentes baseia-se na titulação, no conhecimento da área de atuação e na experiência. As competências distintivas dos docentes deveriam ser foco de desenvolvimento primordial para constituir-se em fontes de vantagem competitiva sustentável para as universidades.

  18. Development of VIS/NIR spectroscopic system for real-time prediction of fresh pork quality

    Science.gov (United States)

    Zhang, Haiyun; Peng, Yankun; Zhao, Songwei; Sasao, Akira

    2013-05-01

    Quality attributes of fresh meat will influence nutritional value and consumers' purchasing power. The aim of the research was to develop a prototype for real-time detection of quality in meat. It consisted of hardware system and software system. A VIS/NIR spectrograph in the range of 350 to 1100 nm was used to collect the spectral data. In order to acquire more potential information of the sample, optical fiber multiplexer was used. A conveyable and cylindrical device was designed and fabricated to hold optical fibers from multiplexer. High power halogen tungsten lamp was collected as the light source. The spectral data were obtained with the exposure time of 2.17ms from the surface of the sample by press down the trigger switch on the self-developed system. The system could automatically acquire, process, display and save the data. Moreover the quality could be predicted on-line. A total of 55 fresh pork samples were used to develop prediction model for real time detection. The spectral data were pretreated with standard normalized variant (SNV) and partial least squares regression (PLSR) was used to develop prediction model. The correlation coefficient and root mean square error of the validation set for water content and pH were 0.810, 0.653, and 0.803, 0.098 respectively. The research shows that the real-time non-destructive detection system based on VIS/NIR spectroscopy can be efficient to predict the quality of fresh meat.

  19. ArtifactVis2: Managing real-time archaeological data in immersive 3D environments

    KAUST Repository

    Smith, Neil

    2013-10-01

    In this paper, we present a stereoscopic research and training environment for archaeologists called ArtifactVis2. This application enables the management and visualization of diverse types of cultural datasets within a collaborative virtual 3D system. The archaeologist is fully immersed in a large-scale visualization of on-going excavations. Massive 3D datasets are seamlessly rendered in real-time with field recorded GIS data, 3D artifact scans and digital photography. Dynamic content can be visualized and cultural analytics can be performed on archaeological datasets collected through a rigorous digital archaeological methodology. The virtual collaborative environment provides a menu driven query system and the ability to annotate, markup, measure, and manipulate any of the datasets. These features enable researchers to re-experience and analyze the minute details of an archaeological site\\'s excavation. It enhances their visual capacity to recognize deep patterns and structures and perceive changes and reoccurrences. As a complement and development from previous work in the field of 3D immersive archaeological environments, ArtifactVis2 provides a GIS based immersive environment that taps directly into archaeological datasets to investigate cultural and historical issues of ancient societies and cultural heritage in ways not possible before. © 2013 IEEE.

  20. Pi-dimer of an aniline dimer: an ESR-UV-vis spectroelectrochemical study.

    Science.gov (United States)

    Petr, Andreas; Wei, Di; Kvarnström, Carita; Ivaska, Ari; Dunsch, Lothar

    2007-11-01

    It is shown for the first time that the most important intermediate formed during aniline polymerization, the p-aminodiphenylamine, forms a pi-dimer under oxidation at room temperature in acidified organic solvents that are used in electropolymerization. N-Phenylquinonediimine, which is generally assumed to be formed under oxidation, is only formed in basic solutions and in ionic liquids. Most of the mechanistic studies reported so far take the formation of N-phenylquinonediimine under consideration, although it is not consistent with the UV-vis spectra measured during oxidation of p-aminodiphenylamine. The formation of a pi-dimer is very well consistent with the electronic spectra of the oxidation product. In this way the pi-dimer is very important for the interpretation of the UV-vis spectra of higher oligomers and polyaniline as well. Furthermore, it offers a new interpretation of the redox behavior of p-aminodiphenylamine as found by cyclic voltammetry and has to be considered in the mechanism of the electrochemical polyaniline formation.

  1. A Study of Photoluminiscence and UV-Vis in Enhanced GaN Nanofibers

    Science.gov (United States)

    Robles-Garcia, Joshua; Melendez-Zambrana, Anamaris; Ramos, Idalia

    2014-03-01

    The photoluminiscence (PL) and UV-Vis properties of Gallium Nitride (GaN) nanofibers were investigated for samples fabricated with a precursor solution containing Gallium Nitrate Hydrate, Cellulose Acetate, and Urea in the solvents Dimethylacetamide (DMA) and Acetone. GaN is a wide bandgap (3.4 eV) semiconductor that can be used in a variety of applications including solid-state lighting, high power, and high frequency devices. In previous work, we produced polycrystalline GaN nanofibers with wurtzite structure, using the electrospinning method and a thermal treatment in nitrogen and ammonia at 1000C. In this research we study the addition of urea to the precursor solution to enhance the crystallinity of the fibers at lower sintering temperatures. The molar ratios of urea added to the precursor range from 0 to 1.7 M. After electrospinning the fibers were sintered in Nitrogen at 450C for 3 hours and then, under ammonia gas flow at 900C for 5 hours. X-Ray Diffraction (XRD), UV-Vis spectroscopy, and PL measurements at room temperature were used to study the structural and optical properties of the fibers during the sintering process. This work was sponsored by UPRH PREM (NSF-DMR-0934195).

  2. Rapid non-destructive assessment of pork edible quality by using VIS/NIR spectroscopic technique

    Science.gov (United States)

    Zhang, Leilei; Peng, Yankun; Dhakal, Sagar; Song, Yulin; Zhao, Juan; Zhao, Songwei

    2013-05-01

    The objectives of this research were to develop a rapid non-destructive method to evaluate the edible quality of chilled pork. A total of 42 samples were packed in seal plastic bags and stored at 4°C for 1 to 21 days. Reflectance spectra were collected from visible/near-infrared spectroscopy system in the range of 400nm to 1100nm. Microbiological, physicochemical and organoleptic characteristics such as the total viable counts (TVC), total volatile basic-nitrogen (TVB-N), pH value and color parameters L* were determined to appraise pork edible quality. Savitzky-Golay (SG) based on five and eleven smoothing points, Multiple Scattering Correlation (MSC) and first derivative pre-processing methods were employed to eliminate the spectra noise. The support vector machines (SVM) and partial least square regression (PLSR) were applied to establish prediction models using the de-noised spectra. A linear correlation was developed between the VIS/NIR spectroscopy and parameters such as TVC, TVB-N, pH and color parameter L* indexes, which could gain prediction results with Rv of 0.931, 0.844, 0.805 and 0.852, respectively. The results demonstrated that VIS/NIR spectroscopy technique combined with SVM possesses a powerful assessment capability. It can provide a potential tool for detecting pork edible quality rapidly and non-destructively.

  3. Determination of polyphenolic compounds of red wines by UV-VIS-NIR spectroscopy and chemometrics tools.

    Science.gov (United States)

    Martelo-Vidal, M J; Vázquez, M

    2014-09-01

    Spectral analysis is a quick and non-destructive method to analyse wine. In this work, trans-resveratrol, oenin, malvin, catechin, epicatechin, quercetin and syringic acid were determined in commercial red wines from DO Rías Baixas and DO Ribeira Sacra (Spain) by UV-VIS-NIR spectroscopy. Calibration models were developed using principal component regression (PCR) or partial least squares (PLS) regression. HPLC was used as reference method. The results showed that reliable PLS models were obtained to quantify all polyphenols for Rías Baixas wines. For Ribeira Sacra, feasible models were obtained to determine quercetin, epicatechin, oenin and syringic acid. PCR calibration models showed worst reliable of prediction than PLS models. For red wines from mencía grapes, feasible models were obtained for catechin and oenin, regardless the geographical origin. The results obtained demonstrate that UV-VIS-NIR spectroscopy can be used to determine individual polyphenolic compounds in red wines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Experimental and theoretical studies on IR, Raman, and UV-Vis spectra of quinoline-7-carboxaldehyde.

    Science.gov (United States)

    Kumru, M; Küçük, V; Kocademir, M; Alfanda, H M; Altun, A; Sarı, L

    2015-01-05

    Spectroscopic properties of quinoline-7-carboxaldehyde (Q7C) have been studied in detail both experimentally and theoretically. The FT-IR (4000-50 cm(-1)), FT-Raman (4000-50 cm(-1)), dispersive-Raman (3500-50 cm(-1)), and UV-Vis (200-400 nm) spectra of Q7C were recorded at room temperature (25 °C). Geometry parameters, potential energy surface about CCH(O) bond, harmonic vibrational frequencies, IR and Raman intensities, UV-Vis spectrum, and thermodynamic characteristics (at 298.15K) of Q7C were computed at Hartree-Fock (HF) and density functional B3LYP levels employing the 6-311++G(d,p) basis set. Frontier molecular orbitals, molecular electrostatic potential, and Mulliken charge analyses of Q7C have also been performed. Q7C has two stable conformers that are energetically very close to each other with slight preference to the conformer that has oxygen atom of the aldehyde away from the nitrogen atom of the quinoline. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Ideologia, visões de mundo e práticas socioambientais no paisagismo

    Directory of Open Access Journals (Sweden)

    Luiz Pedro de Melo Cesar

    2003-12-01

    Full Text Available O artigo apresenta o paisagismo como prática socioambiental que expressa valores culturais e subordina-se a condicionantes ecológicos. Essa combinação revela relações entre sociedade e natureza e reflete visões de mundo predominantes. Interpretações sobre a realidade existem desde o início da história humana. Conceitos de ordem, racionalidade e controle impregnam o mundo ocidental, enquanto se manifestam no processo de urbanização e no paisagismo. A discussão estabelece um pano de fundo para a explorar o papel das visões de mundo na busca da cidade ideal e no paisagismo. Argumenta que diferentes modelos de paisagismo valorizam dimensões diferenciadas da realidade. Recentemente, o paisagismo evoluiu ao adotar princípios da ecologia e a compreensão ambiental. Ainda em construção, o paisagismo ambiental expressa muito das contradições da sociedade atual.

  6. Ionic liquid for in situ Vis/NIR and Raman spectroelectrochemistry: Doping of carbon nanostructures.

    Science.gov (United States)

    Kavan, Ladislav; Dunsch, Lothar

    2003-09-15

    1-butyl-3-methylimidazolium tetrafluoroborate (an ionic liquid) is an advantageous electrolyte for the study of charge-transfer reactions at single-walled carbon nanotubes (SWCNTs) and fullerene peapods (C60@SWCNT). Compared to traditional electrolyte solutions, this medium offers a broader window of electrochemical potentials to be applied, and favorable optical properties for in situ Vis/NIR and Raman spectroelectrochemistry of nano-carbon species. The electrochemistry of both nanotubes and peapods is dominated by their capacitive double-layer charging. Vis/NIR spectroelectrochemistry confirms the charging-induced bleaching of transitions between Van Hove singularities. At high positive potentials, new optical transitions were activated in partly filled valence band. The bleaching of optical transitions is mirrored by the quenching of resonance Raman scattering in the region of tube-related modes. The Raman frequency of the tangential displacement mode of SWCNT shifts to blue upon both anodic and cathodic charging in the ionic liquid. The Raman modes of intratubular C60 exhibit a considerable intensity increase upon anodic doping of peapods.

  7. Protonation effects on the UV/Vis absorption spectra of imatinib: a theoretical and experimental study.

    Science.gov (United States)

    Grante, Ilze; Actins, Andris; Orola, Liana

    2014-08-14

    An experimental and theoretical investigation of protonation effects on the UV/Vis absorption spectra of imatinib showed systematic changes of absorption depending on the pH, and a new absorption band appeared below pH 2. These changes in the UV/Vis absorption spectra were interpreted using quantum chemical calculations. The geometry of various imatinib cations in the gas phase and in ethanol solution was optimized with the DFT/B3LYP method. The resultant geometries were compared to the experimentally determined crystal structures of imatinib salts. The semi-empirical ZINDO-CI method was employed to calculate the absorption lines and electronic transitions. Our study suggests that the formation of the extra near-UV absorption band resulted from an increase of imatinib trication concentration in the solution, while the rapid increase of the first absorption maximum could be attributed to both the formation of imatinib trication and tetracation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. The UV-VIS spectrophotometry applied to color and stability study in colored mortars

    Directory of Open Access Journals (Sweden)

    Alejandre, F. J.

    1999-06-01

    Full Text Available In the field of methodologies for color studying, a research of it has been done on colored mortars by applying uv-vis spectrophotometry, instrumental technique which can be used for solid materials works, and previously applied to building materials study. Results obtained show that the mentioned technique permits to evaluate quantitatively and qualitatively colors in an easy and objective way, besides nowadays advantages of the instrumental analysis: digital color register, computerized data processing, and precision and exactness increment in chromatic comparisons.

    Dentro de las metodologías existentes para el estudio del color, se ha realizado una investigación del mismo en morteros coloreados por medio de la espectrofotometría UV-VIS, técnica instrumental que es adaptable al trabajo con materiales sólidos, y que ha sido aplicada anteriormente en el estudio de diversos materiales de construcción. Los resultados obtenidos muestran cómo la citada técnica permite además de evaluar cualitativamente y cuantitativamente los colores de forma sencilla y objetiva, el disponer de las ventajas que conlleva actualmente el análisis instrumental: registro digital del color, tratamiento informatizado de datos y aumento de precisión y exactitud en las comparaciones cromáticas.

  9. VisANT 4.0: Integrative network platform to connect genes, drugs, diseases and therapies.

    Science.gov (United States)

    Hu, Zhenjun; Chang, Yi-Chien; Wang, Yan; Huang, Chia-Ling; Liu, Yang; Tian, Feng; Granger, Brian; Delisi, Charles

    2013-07-01

    With the rapid accumulation of our knowledge on diseases, disease-related genes and drug targets, network-based analysis plays an increasingly important role in systems biology, systems pharmacology and translational science. The new release of VisANT aims to provide new functions to facilitate the convenient network analysis of diseases, therapies, genes and drugs. With improved understanding of the mechanisms of complex diseases and drug actions through network analysis, novel drug methods (e.g., drug repositioning, multi-target drug and combination therapy) can be designed. More specifically, the new update includes (i) integrated search and navigation of disease and drug hierarchies; (ii) integrated disease-gene, therapy-drug and drug-target association to aid the network construction and filtering; (iii) annotation of genes/drugs using disease/therapy information; (iv) prediction of associated diseases/therapies for a given set of genes/drugs using enrichment analysis; (v) network transformation to support construction of versatile network of drugs, genes, diseases and therapies; (vi) enhanced user interface using docking windows to allow easy customization of node and edge properties with build-in legend node to distinguish different node type. VisANT is freely available at: http://visant.bu.edu.

  10. Condutas reabilitacionais em pacientes com baixa visão Rehabilitational management of low vision patients

    Directory of Open Access Journals (Sweden)

    Micheline Borges Lucas

    2003-01-01

    Full Text Available OBJETIVO: Determinar os principais diagnósticos etiológicos dos pacientes com baixa visão e apresentar as condutas reabilitacionais mais indicadas de acordo com idade, acuidade visual e necessidades de cada grupo de acordo com a doença de base. MÉTODOS: Realizou-se estudo transversal, no qual pesquisaram-se 229 pacientes com baixa visão no período de dois anos, dos quais 27 (11,8% foram excluídos por apresentarem acuidade visual maior que 20/60. Os dados analisados foram idade, sexo, motivo de procura de serviço de visão subnormal, diagnóstico, acuidade visual para perto e para longe com e sem auxílio óptico, recurso óptico indicado, se houve indicação para adaptação de auxílio óptico e estimulação visual. RESULTADOS: O diagnóstico mais freqüente em crianças e adolescentes foi catarata congênita binocular; na faixa etária de 20 a 59 anos prevaleceu retinose pigmentar e no grupo de idade maior que 60 anos os diagnósticos mais freqüentes foram glaucoma e degeneração macular relacionada à idade. CONCLUSÃO: Entre os pacientes com idade de 7 a 39 anos o auxílio óptico para longe mais indicado foi telelupa monocular de 2,5X de aumento. Acima de 60 anos foram mais indicados os auxílios ópticos para perto do tipo lentes asféricas. Das 117 pessoas que receberam indicação de auxílio para perto, 71,0% atingiram visão de até 1,25M e dos 59 pacientes que receberam indicação de auxílio para longe, 56,0% atingiram visão de até 20/60.PURPOSE: To determine the principal etiological diagnoses in low vision patients and to analyze their rehabilitational management. The studies were performed according to age, visual accuracy and the needs of each group. METHODS: The transversal study observed 229 low vision patients for two years and 27 (11.8% patients were excluded because their vision was better than 20/60. The analysis was carried out according to the following factors: age, sex, reason for seeking help at a

  11. Validation of quantitative analysis method for triamcinolone in ternary complexes by UV-Vis spectrophotometry

    Directory of Open Access Journals (Sweden)

    GEORGE DARLOS A. AQUINO

    2011-06-01

    Full Text Available Triamcinolone (TRI, a drug widely used in the treatment of ocular inflammatory diseases, is practically insoluble in water, which limits its use in eye drops. Cyclodextrins (CDs have been used to increase the solubility or dissolution rate of drugs. The purpose of the present study was to validate a UV-Vis spectrophotometric method for quantitative analysis of TRI in inclusion complexes with beta-cyclodextrin (B-CD associated with triethanolamine (TEA (ternary complex. The proposed analytical method was validated with respect to the parameters established by the Brazilian regulatory National Agency of Sanitary Monitoring (ANVISA. The analytical measurements of absorbance were made at 242nm, at room temperature, in a 1-cm path-length cuvette. The precision and accuracy studies were performed at five concentration levels (4, 8, 12, 18 and 20μg.mL-1. The B-CD associated with TEA did not provoke any alteration in the photochemical behavior of TRI. The results for the measured analytical parameters showed the success of the method. The standard curve was linear (r2 > 0.999 in the concentration range from 2 to 24 μg.mL-1. The method achieved good precision levels in the inter-day (relative standard deviation-RSD <3.4% and reproducibility (RSD <3.8% tests. The accuracy was about 80% and the pH changes introduced in the robustness study did not reveal any relevant interference at any of the studied concentrations. The experimental results demonstrate a simple, rapid and affordable UV-Vis spectrophotometric method that could be applied to the quantitation of TRI in this ternary complex. Keywords: Validation. Triamcinolone. Beta-cyclodextrin. UV- Vis spectrophotometry. Ternary complexes. RESUMO Validação de método de análise quantitativa para a triancinolona a partir de complexo ternário por espectrofotometria de UV-Vis A triancinolona (TRI é um fármaco amplamente utilizado no tratamento de doenças inflamatórias do globo ocular e

  12. The future of VIS-IR hyperspectral remote sensing for the exploration of the solar system

    Science.gov (United States)

    Filacchione, Gianrico

    2017-06-01

    In the last 30 years our understanding of the Solar System has greatly advanced thanks to the introduction of VIS-IR imaging spectrometers which have provided hyperspectral views of planets, satellites, asteroids, comets and rings. By providing moderate resolution images and reflectance spectra for each pixel at the same time, these instruments allow to elaborate spectral-spatial models for very different targets: when used to observe surfaces, hyperspectral methods permit to retrieve endmembers composition (minerals, ices, organics, liquids), mixing state among endmembers (areal, intimate, intraparticle), physical properties (particle size, roughness, temperature) and to correlate these quantities with geological and morphological units. Similarly, morphological, dynamical and compositional studies of gaseous and aerosol species can be retrieved for planetary atmospheres, exospheres and auroras. To achieve these results, very different optical layouts, detectors technologies and observing techniques have been adopted in the last decades, going from very large and complex payloads, like ISM (IR Spectral Mapper) on russian mission Phobos to Mars and NIMS (Near IR Mapping Spectrometer) on US Galileo mission to Jupiter, which were the first hyperspectral imagers to flow aboard planetary missions, to more recent compact and performing experiments. The future of VIS-IR hyperspectral remote sensing is challenging because the complexity of modern planetary missions drives towards the realization of increasingly smaller, lighter and more performing payloads able to survive in harsh radiation and planetary protected environments or to operate from demanding platforms like landers, rovers and cubesats. As a development for future missions, one can foresee that apart instruments designed around well-consolidated optical solutions relying on prisms or gratings as dispersive elements, a new class of innovative hyperspectral imagers will rise: recent developments in

  13. A rapid approach for measuring silver nanoparticle concentration and dissolution in seawater by UV-Vis.

    Science.gov (United States)

    Sikder, Mithun; Lead, Jamie R; Chandler, G Thomas; Baalousha, Mohammed

    2017-04-12

    Detection and quantification of engineered nanoparticles (NPs) in environmental systems is challenging and requires sophisticated analytical equipment. Furthermore, dissolution is an important environmental transformation process for silver nanoparticles (AgNPs) which affects the size, speciation and concentration of AgNPs in natural water systems. Herein, we present a simple approach for the detection, quantification and measurement of dissolution of PVP-coated AgNPs (PVP-AgNPs) based on monitoring their optical properties (extinction spectra) using UV-vis spectroscopy. The dependence of PVP-AgNPs extinction coefficient (ɛ) and maximum absorbance wavelength (λmax) on NP size was experimentally determined. The concentration, size, and extinction spectra of PVP-AgNPs were characterized during dissolution in 30ppt synthetic seawater. AgNPs concentration was determined as the difference between the total and dissolved Ag concentrations measured by inductively coupled plasma-mass spectroscopy (ICP-MS); extinction spectra of PVP-AgNPs were monitored by UV-vis; and size evolution was monitored by atomic force microscopy (AFM) over a period of 96h. Empirical equations for the dependence of maximum absorbance wavelength (λmax) and extinction coefficient (ɛ) on NP size were derived. These empirical formulas were then used to calculate the size and concentration of PVP-AgNPs, and dissolved Ag concentration released from PVP-AgNPs in synthetic seawater at variable particle concentrations (i.e. 25-1500μgL(-1)) and in natural seawater at particle concentration of 100μgL(-1). These results suggest that UV-vis can be used as an easy and quick approach for detection and quantification (size and concentration) of sterically stabilized PVP-AgNPs from their extinction spectra. This approach can also be used to monitor the release of Ag from PVP-AgNPs and the concurrent NP size change. Finally, in seawater, AgNPs dissolve faster and to a higher extent with the decrease in NP

  14. Visible near infrared diffuse reflectance spectroscopy (VisNIR DRS) for rapid measurement of organic matter in compost.

    Science.gov (United States)

    McWhirt, Amanda L; Weindorf, David C; Chakraborty, Somsubhra; Li, Bin

    2012-10-01

    Commercial compost is the inherently variable organic product of a controlled decomposition process. In the USA, assessment of compost's physicochemical parameters presently relies on standard laboratory analyses set forth in Test Methods for the Examination of Composting and Compost (TMECC). A rapid, field-portable means of assessing the organic matter (OM) content of compost products would be useful to help producers ensure optimal uniformity in their compost products. Visible near infrared diffuse reflectance spectroscopy (VisNIR DRS) is a rapid, proximal-sensing technology proven effective at quantifying organic matter levels in soils. As such, VisNIR DRS was evaluated to assess its applicability to compost. Thirty-six compost samples representing a wide variety of source materials and moisture content were collected and scanned with VisNIR DRS under moist and oven-dry conditions. Partial least squares (PLS) regression and principal component regression (PCR) were used to relate the VisNIR DRS spectra with laboratory-measured OM to build compost OM prediction models. Raw reflectance, and first- and second-derivatives of the reflectance spectra were considered. In general, PLS regression outperformed PCR and the oven-dried first-derivative PLS model produced an r(2) value of 0.82 along with a residual prediction deviation value of 1.72. As such, VisNIR DRS shows promise as a suitable technique for the analysis of compost OM content for dried samples.

  15. Avaliação da Visão Funcional (AVIF) para crianças de dois a seis anos com baixa visão: exame de confiabilidade e de validade

    OpenAIRE

    Luciana Drummond de Figueiredo Rossi

    2010-01-01

    A AVIF-2 a 6 anos é um método de Avaliação da Visão Funcional para crianças com baixa visão. Ele foi elaborado por uma Fisioterapeuta e uma Terapeuta Ocupacional do Setor de Baixa Visão Infantil do Hospital São Geraldo (Hospital das Clínicas, da UFMG). No presente estudo, foram analisadas as propriedades psicométricas (confiabilidade e validade) da AVIF-2 a 6 anos e a capacidade desse teste para discriminar os diferentes níveis de resposta visual. Após realização de um painel com profissio...

  16. Confiabilidade da avaliação da visão funcional para crianças com baixa visão de dois a seis anos: em busca de evidências

    Directory of Open Access Journals (Sweden)

    Luciana Drummond de Figueiredo Rossi

    2012-08-01

    Full Text Available OBJETIVOS: Avaliar a confiabilidade interexaminadores, fazer o teste-reteste e verificar a consistência interna da avaliação da visão funcional para crianças com baixa visão de dois a seis anos de idade (AVIF-2 a 6 anos. MÉTODOS: Foram testados sete domínios: fixação visual, seguimento visual, campo visual de confrontação, coordenação olho-mão, visão de contraste, deslocamento no ambiente e visão de cores, em 40 crianças, 20 com baixa visão e 20 sem alterações visuais. A consistência interna foi examinada para o teste de todas as crianças e a confiabilidade interexaminadores e teste-reteste para 12 delas. RESULTADOS: Seis domínios apresentaram ao teste-reteste coeficiente de correlação intraclasse com valores de 0,5361 a 1,000. Para o domínio deslocamento no ambiente esse coeficiente foi de 0,37. Na confiabilidade interexaminadores, somente o campo visual de confrontação apresentou valor abaixo do esperado (0,3901. O coeficiente kappa ponderado obteve resultados que variaram de -0,087 a 1,000. O valor do alfa de Cronbach variou de 0,584 (no deslocamento no ambiente a 0,973 (na visão de contraste. CONCLUSÃO: A AVIF-2 a 6 anos apresentou bons índices de confiabilidade, mas a confiabilidade dos domínios, quando analisados isoladamente, precisa ser aprimorada.

  17. Growth and Stabilization of Silver Nanoplates in Aqueous Solvent Monitored Through UV-Vis Spectra

    Science.gov (United States)

    Tian, Xue-lin; Wang, Wei-hua; Chen, Kai; Cao, Geng-yu

    2006-08-01

    Silver nanoplates were prepared through a visible light induced reduction process by a reaction between sodium citrate and silver nitrate in an aqueous solvent at room temperature. UV-Vis spectra were employed to monitor the growth of the silver nanoplates. The resulting spectra indicated that, at an early stage, the products were spherical particles with planar nanoparticles appearing and growing subsequently. In the last stages of the process, some spherical particles were consumed by the growth of the nanoparticles, through an Ostwald ripening mechanism. Furthermore, it was found that the addition of either Poly(Vinyl Pyrrolidone) (PVP) or excessive citrate could stabilize the colloidal system effectively, and that rigorous stirring was necessary for the anticipant products. Introduction of a large quantities of sodium hydroxide can dramatically accelerate the reactive rate of the photoreduction process.

  18. Microreactors with integrated UV/Vis spectroscopic detection for online process analysis under segmented flow.

    Science.gov (United States)

    Yue, Jun; Falke, Floris H; Schouten, Jaap C; Nijhuis, T Alexander

    2013-12-21

    Combining reaction and detection in multiphase microfluidic flow is becoming increasingly important for accelerating process development in microreactors. We report the coupling of UV/Vis spectroscopy with microreactors for online process analysis under segmented flow conditions. Two integration schemes are presented: one uses a cross-type flow-through cell subsequent to a capillary microreactor for detection in the transmission mode; the other uses embedded waveguides on a microfluidic chip for detection in the evanescent wave field. Model experiments reveal the capabilities of the integrated systems in real-time concentration measurements and segmented flow characterization. The application of such integration for process analysis during gold nanoparticle synthesis is demonstrated, showing its great potential in process monitoring in microreactors operated under segmented flow.

  19. Discrimination of whisky brands and counterfeit identification by UV-Vis spectroscopy and multivariate data analysis.

    Science.gov (United States)

    Martins, Angélica Rocha; Talhavini, Márcio; Vieira, Maurício Leite; Zacca, Jorge Jardim; Braga, Jez Willian Batista

    2017-08-15

    The discrimination of whisky brands and counterfeit identification were performed by UV-Vis spectroscopy combined with partial least squares for discriminant analysis (PLS-DA). In the proposed method all spectra were obtained with no sample preparation. The discrimination models were built with the employment of seven whisky brands: Red Label, Black Label, White Horse, Chivas Regal (12years), Ballantine's Finest, Old Parr and Natu Nobilis. The method was validated with an independent test set of authentic samples belonging to the seven selected brands and another eleven brands not included in the training samples. Furthermore, seventy-three counterfeit samples were also used to validate the method. Results showed correct classification rates for genuine and false samples over 98.6% and 93.1%, respectively, indicating that the method can be helpful for the forensic analysis of whisky samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. UV-vis absorption spectroscopy and multivariate analysis as a method to discriminate tequila

    Science.gov (United States)

    Barbosa-García, O.; Ramos-Ortíz, G.; Maldonado, J. L.; Pichardo-Molina, J. L.; Meneses-Nava, M. A.; Landgrave, J. E. A.; Cervantes-Martínez, J.

    2007-01-01

    Based on the UV-vis absorption spectra of commercially bottled tequilas, and with the aid of multivariate analysis, it is proved that different brands of white tequila can be identified from such spectra, and that 100% agave and mixed tequilas can be discriminated as well. Our study was done with 60 tequilas, 58 of them purchased at liquor stores in various Mexican cities, and two directly acquired from a distillery. All the tequilas were of the "white" type, that is, no aged spirits were considered. For the purposes of discrimination and quality control of tequilas, the spectroscopic method that we present here offers an attractive alternative to the traditional methods, like gas chromatography, which is expensive and time-consuming.

  1. [UV-Vis spectroscopic characterization of Sudan series in organic solution].

    Science.gov (United States)

    Zhang, Jin-ping; Yang, Sheng-ke; Duan, Lei; Wang, Wen-ke

    2007-05-01

    The UV-Vis spectroscopic characterization of Sudan I, Sudan III and Sudan IV in nonpolar solvent ligarine, polar solvent acetonitrile, and acetonitrile-water mixture was studied. The characteristic absorption peaks of sudan series were a little red shifted in polar solvent compared to that in nonpolar solvent. In acetonitrile-water mixture the red shift of characteristic absorption peaks of sudan I and sudan III is respectively 13 and 8 nm, but the characteristic absorption peaks of sudan IV are red shifted before blue shifted. The increased adsorption strength of Sudan I, Sudan III and Sudan IV is 34.5%, 11% and 2.5% respectively. For these, the important reason is that the destroyed intramolecular hydrogen bond in Sudan series enlarges the scope of the pi delocalized bond in polar solvent.

  2. Defects in UV-vis-NIR reflectance spectra as method for forgery detections in writing documents

    Science.gov (United States)

    Somma, F.; Aloe, P.; Schirripa Spagnolo, G.

    2010-11-01

    Documents have taken up a very important place in our society. Frauds committed in connection with documents are not at all uncommon, and, in fact, represent a very large domain of the forensic science called "questioned documents". In the field of forensic examination of questioned documents, the legitimacy of an ink entry is often an essential question. A common type of forgery consists in materially altering an existing writing or adding a new writing. These changes can be characterized by means of optical spectroscopy. The aim of this work is to perform the UV-vis-NIR reflectance spectrophotometry to analyze a range of blue and black commercial ballpoint pens, in order to investigate the discriminating abilities of the different inks found on the same document.

  3. Method development and validation of potent pyrimidine derivative by UV-VIS spectrophotometer.

    Science.gov (United States)

    Chaudhary, Anshu; Singh, Anoop; Verma, Prabhakar Kumar

    2014-12-01

    A rapid and sensitive ultraviolet-visible (UV-VIS) spectroscopic method was developed for the estimation of pyrimidine derivative 6-Bromo-3-(6-(2,6-dichlorophenyl)-2-(morpolinomethylamino) pyrimidine4-yl) -2H-chromen-2-one (BT10M) in bulk form. Pyrimidine derivative was monitored at 275 nm with UV detection, and there is no interference of diluents at 275 nm. The method was found to be linear in the range of 50 to 150 μg/ml. The accuracy and precision were determined and validated statistically. The method was validated as a guideline. The results showed that the proposed method is suitable for the accurate, precise, and rapid determination of pyrimidine derivative. Graphical Abstract Method development and validation of potent pyrimidine derivative by UV spectroscopy.

  4. UV-vis spectroscopic Investigation on {gamma}-irradiated alkali aluminoborate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, N. [Department of Physics, K.M.V., Jalandhar (India); Singh, N.P. [Dean, Punjab Technical University, Jalandhar (India); Baccaro, S. [ENEA/FIM, Casaccia RC, Via Anguillarese 301, S. Maria di Galeria, Rome 00060 (Italy); Sharma, G., E-mail: sharmagopi28@yahoo.com [Department of Physics, K.M.V., Jalandhar (India)

    2012-04-15

    This research paper reports about the change in optical spectra of alkali aluminoborate glasses under high dose of gamma irradiation. Effect of irradiation on visible spectra finds remarkable applications in optoelectronic materials. Glasses with a host matrix composed of M{sub 2}O (where M=Na, K){sub ,} Al{sub 2}O{sub 3,} B{sub 2}O{sub 3} were prepared by conventional melt quench technique. Gamma irradiation was performed at a dose-rate of 573 Gy/h to a total dose of 50 kGy. Samples were characterised before and immediately after irradiation by UV-vis transmission spectra in the range of 200-800 nm. The induced absorption coefficient and loss of transmission due to irradiation were attributed to the nature of alkali metals as well as the host matrix.

  5. Four Brazilian Maytenus salicifolia Reissek (Celastraceae groups studied by TLC and UV/Vis spectrophotometry

    Directory of Open Access Journals (Sweden)

    Frederico N. Valladão

    Full Text Available The great variety of angiosperms shows the need to development of botanical classification systems supported by phytochemistry, biochemistry and others. Recently, techniques of analysis used for the isolation and characterization of secondary metabolites have been employed as auxiliary quick and efficient methods for the identification and classification of plant species. M. salicifolia is popularly known in Brazil, as "small coffee" and decoct obtained from its fresh leaves is topically used to alleviate itches and other skins allergic symptoms. This work presents the use of TLC and UV/Vis spectrophotomety processes to be applied like an auxiliary method in botanical taxonomy. The results demonstrate that this process can be used in differentiation of the same genera species, and in the selection of chemical variations between individuals of the same species.

  6. Defects in UV-vis-NIR reflectance spectra as method for forgery detections in writing documents

    Energy Technology Data Exchange (ETDEWEB)

    Somma, F; Aloe, P; Schirripa Spagnolo, G

    2010-11-01

    Documents have taken up a very important place in our society. Frauds committed in connection with documents are not at all uncommon, and, in fact, represent a very large domain of the forensic science called 'questioned documents'. In the field of forensic examination of questioned documents, the legitimacy of an ink entry is often an essential question. A common type of forgery consists in materially altering an existing writing or adding a new writing. These changes can be characterized by means of optical spectroscopy. The aim of this work is to perform the UV-vis-NIR reflectance spectrophotometry to analyze a range of blue and black commercial ballpoint pens, in order to investigate the discriminating abilities of the different inks found on the same document.

  7. Development and Evaluation of a VisSim/Comm Based Minimum Shift Keying Simulator

    Science.gov (United States)

    Baltzis, Konstantinos B.; Goudos, Sotirios K.

    2010-01-01

    One of the most prominent data transmission techniques in modern digital communications is minimum shift keying (MSK) modulation. In recent years, the method has gained popularity due to several features highly desirable in telecommunications. In this paper, we develop an MSK transceiver in the VisSim/Comm simulation environment. The main benefit of our proposal is the detailed and realistic representation of the transceiver; in contrast to MSK building blocks in the simulation libraries, users can gain information in time and spectral domain at any point in the structure. We present a detailed description of the simulator and give representative examples that exhibit the simulator's performance and accuracy. We also discuss an educational application of the simulator. In that way physics students can study the simulator characteristics and evaluate its efficiency.

  8. [Measurement of Water COD Based on UV-Vis Spectroscopy Technology].

    Science.gov (United States)

    Wang, Xiao-ming; Zhang, Hai-liang; Luo, Wei; Liu, Xue-mei

    2016-01-01

    Ultraviolet/visible (UV/Vis) spectroscopy technology was used to measure water COD. A total of 135 water samples were collected from Zhejiang province. Raw spectra with 3 different pretreatment methods (Multiplicative Scatter Correction (MSC), Standard Normal Variate (SNV) and 1st Derivatives were compared to determine the optimal pretreatment method for analysis. Spectral variable selection is an important strategy in spectrum modeling analysis, because it tends to parsimonious data representation and can lead to multivariate models with better performance. In order to simply calibration models, the preprocessed spectra were then used to select sensitive wavelengths by competitive adaptive reweighted sampling (CARS), Random frog and Successive Genetic Algorithm (GA) methods. Different numbers of sensitive wavelengths were selected by different variable selection methods with SNV preprocessing method. Partial least squares (PLS) was used to build models with the full spectra, and Extreme Learning Machine (ELM) was applied to build models with the selected wavelength variables. The overall results showed that ELM model performed better than PLS model, and the ELM model with the selected wavelengths based on CARS obtained the best results with the determination coefficient (R2), RMSEP and RPD were 0.82, 14.48 and 2.34 for prediction set. The results indicated that it was feasible to use UV/Vis with characteristic wavelengths which were obtained by CARS variable selection method, combined with ELM calibration could apply for the rapid and accurate determination of COD in aquaculture water. Moreover, this study laid the foundation for further implementation of online analysis of aquaculture water and rapid determination of other water quality parameters.

  9. The Lowest Triplet of Tetracyanoquinodimethane via UV-vis Absorption Spectroscopy with Br-Containing Solvents.

    Science.gov (United States)

    Khvostenko, Olga G; Kinzyabulatov, Renat R; Khatymova, Laysan Z; Tseplin, Evgeniy E

    2017-10-05

    This study was undertaken to find the previously unknown lowest triplet of the isolated molecule of tetracyanoquinodimethane (TCNQ), which is a widely used organic semiconductor. The problem is topical because the triplet excitation of this compound is involved in some processes which occur in electronic devices incorporating TCNQ and its derivatives, and information on the TCNQ triplet is needed for better understanding of these processes. The lowest triplet of TCNQ was obtained at 1.96 eV using UV-vis absorption spectroscopy with Br-containing solvents. Production of the triplet band with sufficient intensity in the spectra was provided by the capacity of the Br atom to augment the triplet excitation and through using a 100 mm cuvette. The assignment of the corresponding spectral band to the triplet transition was made by observation that this band appeared only in the spectra recorded in Br-containing solvents but not in spectra recorded in other solvents. Additional support for the triplet assignment came from the overall UV-vis absorption spectra of TCNQ recorded in various solvents, using a 10 mm cuvette, in the 1.38-6.5 eV energy range. Singlet transitions of the neutral TCNQ(o) molecule and doublet transitions of the TCNQ(¯) negative ion were identified in these overall spectra and were assigned with TD B3LYP/6-31G calculations. Determination of the lowest triplet of TCNQ attained in this work may be useful for theoretical studies and practical applications of this important compound.

  10. A study of the optical band gap of zinc phthalocyanine nanoparticles using UV-Vis spectroscopy and DFT function

    Science.gov (United States)

    Hamam, Khalil J.; Alomari, Mohammed I.

    2017-06-01

    In the present work, we used the ultraviolet-Visible (UV-Vis) spectroscopy technique to find the optical band gap of zinc phthalocyanine nanoparticles (ZnPc-NP) experimentally. Moreover, we used a time-dependent density functional theory (TDDFT) to simulate the UV-Vis absorption spectrum of ZnPc molecule in gas and solution phases. The ZnPc-NP absorption spectrum shows a shift toward higher energies compared to the bulk ZnPc. The simulated UV-Vis and the experimental nanoparticle's spectrum were found to have a good agreement. The ZnPc energy band gap from the DFT calculations shows how it's possible to get wider range of energy band gap for the ZnPc. The ZnPc-NP's size and shape were examined using the transmission electron microscope (TEM).

  11. Application of Principal Component Analysis to Classify Textile Fibers Based on UV-Vis Diffuse Reflectance Spectroscopy

    Science.gov (United States)

    Wang, C.; Chen, Q.; Hussain, M.; Wu, S.; Chen, J.; Tang, Z.

    2017-07-01

    This study provides a new approach to the classification of textile fibers by using principal component analysis (PCA), based on UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). Different natural and synthetic fibers such as cotton, wool, silk, linen, viscose, and polyester were used. The spectrum of each kind of fiber was scanned by a spectrometer equipped with an integrating sphere. The characteristics of their UV-Vis diffuse reflectance spectra were analyzed. PCA revealed that the first three components represented 99.17% of the total variability in the ultraviolet region. Principal component score scatter plot (PC1 × PC2) of each fiber indicated the accuracy of this classification for these six varieties of fibers. Therefore, it was demonstrated that UV diffuse reflectance spectroscopy can be used as a novel approach to rapid, real-time, fiber identification.

  12. Relação entre visão referida e visão aferida na primeira avaliação oftalmológica

    Directory of Open Access Journals (Sweden)

    Heloísa Silva de Avó

    2016-02-01

    Full Text Available RESUMO Objetivo: Comparar a acuidade visual referida com a aferida no primeiro exame oftalmológico e correlacionar os achados com as variáveis: idade, gênero, escolaridade e nível de acuidade visual. Métodos: Foram levantadas fichas de pacientes atendidos em primeira consulta oftalmológica em uma clínica particular no período de um ano. Comparou-se a acuidade visual referida na história clínica com a obtida no exame oftalmológico. Para a tomada da acuidade visual utilizou-se a tabela de Snellen. Os dados foram tabulados em planilha Excel e submetidos à análise estatística. Adotou-se o nível de significância p=0,05. Resultados: Dos 300 pacientes avaliados, 66 (22% apresentaram baixa visão (BV ao exame oftalmológico; destes 46 (69,69% referiram BV antes do exame e 20 (30,30% não. Em relação ao gênero, não houve diferença estatística na presença (p=0,78 nem na percepção de BV (p=0,30. Todos os pacientes acima dos 75 anos tinham BV (p<0, 0001; não houve diferença estatística significativa em relação à percepção de BV entre as faixas etárias (p=0, 166. O nível de escolaridade não influenciou na presença de BV (p=0, 112 e nem na percepção de BV (p=0, 945. Com relação ao nível da acuidade visual, todos os pacientes com perda visual severa haviam se apercebido deste fato e referiram BV na anamnese. Conclusão: Não houve diferença estatística significativa quanto à presença nem a percepção de BV entre gênero e escolaridade. No entanto, houve diferença estatística na presença de BV em relação às faixas etárias e na percepção de BV em relação ao nível de acuidade visual.

  13. On the Quantitative Potential of Viscoelastic Response (VisR) Ultrasound Using the One-Dimensional Mass-Spring-Damper Model.

    Science.gov (United States)

    Selzo, Mallory R; Moore, Christopher J; Hossain, Md Murad; Palmeri, Mark L; Gallippi, Caterina M

    2016-09-01

    Viscoelastic response (VisR) ultrasound is an acoustic radiation force (ARF)-based imaging method that fits induced displacements to a one-dimensional (1-D) mass-spring-damper (MSD) model to estimate the ratio of viscous to elastic moduli, τ, in viscoelastic materials. Error in VisR τ estimation arises from inertia and acoustic displacement underestimation. These error sources are herein evaluated using finite-element method (FEM) simulations, error correction methods are developed, and corrected VisR τ estimates are compared with true simulated τ values to assess VisR's relevance to quantifying viscoelasticity. With regard to inertia, adding a mass term in series with the Voigt model, to achieve the MSD model, accounts for inertia due to tissue mass when ideal point force excitations are used. However, when volumetric ARF excitations are applied, the induced complex system inertia is not described by the single-degree-of-freedom MSD model, causing VisR to overestimate τ. Regarding acoustic displacement underestimation, associated deformation of ARF-induced displacement profiles further distorts VisR τ estimates. However, median error in VisR τ is reduced to approximately -10% using empirically derived error correction functions applied to simulated viscoelastic materials with viscous and elastic properties representative of tissue. The feasibility of corrected VisR imaging is then demonstrated in vivo in the rectus femoris muscle of an adult with no known neuromuscular disorders. These results suggest VisR's potential relevance to quantifying viscoelastic properties clinically.

  14. Avaliação da visão funcional para crianças com baixa visão de dois a seis anos de idade - estudo comparativo

    Directory of Open Access Journals (Sweden)

    Luciana Drummond de Figueiredo Rossi

    2011-08-01

    Full Text Available OBJETIVO: O objetivo deste trabalho foi apresentar a capacidade da AVIF-2 a 6 anos para discriminar os diferentes níveis de resposta visual de crianças com baixa visão. A AVIF-2 a 6 anos foi criada no Setor de Baixa Visão Infantil do Hospital São Geraldo, Brasil. MÉTODOS: Após a discussão da adequação dos itens do teste, com especialistas de diversas áreas, a AVIF-2 a 6 anos foi aplicada em 40 crianças de dois a seis anos de idade, 20 das quais com baixa visão (Grupo 1 e 20, sem baixa visão (Grupo 2. O grupo 1 foi recrutado do Setor de Baixa Visão Infantil do Hospital São Geraldo. As crianças do grupo 2 foram selecionadas em duas creches públicas. Sete domínios foram estudados: fixação visual, seguimento visual, campo visual de confrontação, coordenação olho-mão, visão de contraste, deslocamento no ambiente e visão de cores. As crianças do grupo 1 foram submetidas a exame oftalmológico completo e as do grupo 2 a triagem oftalmológica. Crianças com baixa visão e alterações neurológicas foram excluidas. Os dois grupos foram emparelhados por idade, sexo e nível socioeconômico, e os dados comparados entre as crianças do grupo geral e dos subgrupos de idade (24 a 35 meses, 36 a 59 meses e 60 a 78 meses e de acuidade visual (1,0 logMAR. RESULTADOS: No total da AVIF-2 a 6 anos e dos domínios fixação visual, seguimento visual, campo visual de confrontação, coordenação olho-mão e deslocamento no ambiente foram constatadas diferenças com significância estatística (p<0,05 entre os dois grupos. As medianas da pontuação da AVIF-2 a 6 anos foram inferiores para as crianças com baixa visão nas três faixas etárias. CONCLUSÃO: A AVIF-2 a 6 anos demonstrou ter potencial para discriminar diferentes níveis de visão funcional, entretanto, serão necessários ainda novos estudos para que o teste possa ser disponibilizado para uso clínico. (ETIC 684/07

  15. ALTIUS: a spaceborne AOTF-based UV-VIS-NIR hyperspectral imager for atmospheric remote sensing

    Science.gov (United States)

    Dekemper, Emmanuel; Fussen, Didier; Van Opstal, Bert; Vanhamel, Jurgen; Pieroux, Didier; Vanhellemont, Filip; Mateshvili, Nina; Franssens, Ghislain; Voloshinov, Vitaly; Janssen, Christof; Elandaloussi, Hadj

    2014-10-01

    Since the recent losses of several atmospheric instruments with good vertical sampling capabilities (SAGE II, SAGE III, GOMOS, SCIAMACHY,. . . ), the scientific community is left with very few sounders delivering concentration pro les of key atmospheric species for understanding atmospheric processes and monitoring the radiative balance of the Earth. The situation is so critical that at the horizon 2020, less than five such instruments will be on duty (most probably only 2 or 3), whereas their number topped at more than 15 in the years 2000. In parallel, recent inter-comparison exercises among the climate chemistry models (CCM) and instrument datasets have shown large differences in vertical distribution of constituents (SPARC CCMVal and Data Initiative), stressing the need for more vertically-resolved and accurate data at all latitudes. In this frame, the Belgian Institute for Space Aeronomy (IASB-BIRA) proposed a gap-filler small mission called ALTIUS (Atmospheric Limb Tracker for the Investigation of the Upcoming Stratosphere), which is currently in preliminary design phase (phase B according to ESA standards). Taking advantage of the good performances of the PROBA platform (PRoject for On-Board Autonomy) in terms of pointing precision and accuracy, on-board processing ressources, and agility, the ALTIUS concept relies on a hyperspectral imager observing limb-scattered radiance and solar/stellar occultations every orbit. The objective is twofold: the imaging feature allows to better assess the tangent height of the sounded air masses (through easier star tracker information validation by scene details recognition), while its spectral capabilities will be good enough to exploit the characteristic signatures of many molecular absorption cross-sections (O3, NO2, CH4, H2O, aerosols,...). The payload will be divided in three independent optical channels, associated to separated spectral ranges (UV: 250- 450 nm, VIS: 440-800 nm, NIR: 900-1800 nm). This approach also

  16. Estimating Soil Organic Carbon Using VIS/NIR Spectroscopy with SVMR and SPA Methods

    Directory of Open Access Journals (Sweden)

    Xiaoting Peng

    2014-03-01

    Full Text Available With 298 heterogeneous soil samples from Yixing (Jiangsu Province, Zhongxiang and Honghu (Hubei Province, this study aimed to combine a successive projections algorithm (SPA with a support vector machine regression (SVMR model (SPA-SVMR model to improve the estimation accuracy of soil organic carbon (SOC contents using the laboratory-based visible and near-infrared (VIS/NIR, 350−2500 nm spectroscopy of soils. The effects of eight spectra pre-processing methods, i.e., Log (1/R, Log (1/R coupled with Savitzky-Golay (SG smoothing (Log (1/R + SG, first derivative with SG smoothing (FD, second derivative with SG smoothing (SD, SG, standard normal variate (SNV, mean center (MC and multiplicative scatter correction (MSC, on SPA-based informative wavelength selection were explored. The SVMR model (i.e., SVMR without SPA and SPA-PLSR model (i.e., SPA combined with partial least squares regression (PLSR were developed and compared with the SPA-SVMR model in order to evaluate the performance of SPA-SVMR. The results indicated that the variables selected by SPA and their distributions were strongly affected by different pre-processing methods, and SG was the optimal pre-processing method for SPA-SVMR model development; the SPA-SVMR model using SG pre-processing and 28 SPA-selected wavelengths obtained a better result (R2V = 0.73, RMSEV = 2.78 g∙kg−1 and RPDV = 1.89 and outperformed the SVMR model (R2V = 0.72, RMSEV = 2.83 g∙kg−1 and RPDV = 1.86 and the SPA-PLSR model (R2V = 0.62, RMSEV = 3.23 g∙kg−1 and RPDV = 1.63. Most of the spectral bands used by the SPA-SVMR model over the near-infrared region were important wavelengths for SOC content estimation. This study demonstrated that the combination of SPA and SVMR is feasible and reliable for estimating SOC content from the VIS/NIR spectra of soils in regions with multiple soil and land-use types.

  17. Vis-NIRS sensor fusion for local, regional and global calibrations of SOC content

    Science.gov (United States)

    Knadel, M.; Deng, F.; Thomsen, A.; Greve, M. H.

    2012-04-01

    The considerable potential of sensor fusion has been recognised and is finding application in soil mapping. Visible-near-infrared (Vis-NIR) diffuse reflectance spectroscopy (DRS) has proven to be an efficient method for measuring soil physical, chemical and biological properties. The objective of this study was to determine whether a Danish national soil spectral library spiked with local samples can give better SOC predictions than the regional or local calibrations alone. It was also investigated if the national library developed using a laboratory sensor can be used to predict field-generated data by the mobile sensor platform (MSP). Local and regional SOC models were based on data obtained from individual fields and from the compilation of the data obtained from six fields in one model, respectively. The prerequisite for using vis-NIR for soil analysis is the development of a soil spectral library. Such library should be based on representative samples for the future application. We selected 2851 samples from a diverse archive of Danish soils and perform a global calibration. Additionally, the national spectral library was spiked with some local samples obtained from the fields under study. Local, regional and global spiked SOC models were compared. The best results from the partial least squares regression (PLSR) were obtained for the regional calibration (RMSEP=0.39, r2=0.93 and RPD=4), followed by the calibrations from the library spiked with local MSP measurements (RMSEP=0.38, r2=0.84, RPD=2.5). Finally, kriging maps of SOC content were validated. The highest root mean square error of prediction (5.4) was generated by the map based on the regional calibration model. The lowest RMSEP (4.1), however, was found for the map generated from the global library spiked with the local samples acquired by MSP. The results from this study show that the national spectral library established using a laboratory sensor can deliver good predictive abilities of SOC on field

  18. Investigation of Temporal Changes in the Suburban Areas Using V-I-S Model

    Science.gov (United States)

    Kaya, S.; Seker, D. Z.; Tanik, A.

    2012-12-01

    Most studies and applications need data on the changes and percent distribution of land use/cover changes in a short period of time. Thus, satellite sensor data is used by different disciplines for determination of the dynamic temporal changes on the earth. Currently, Istanbul is ranked among the first 20 crowded cities of the world. Beyond its current population of around 13 million, this old and ancient city that has hosted many different civilizations during history, has gained an attraction for human settlement due to its geographical location. Today, most of the environmental problems have been overcome by accelerating the realization of infrastructural works; however, such improvement efforts caused a significant decline in the forest areas. Loss of forests has become even more important in the past few years. Forests of the city, particularly those existing in the northern part of the city that has been accepted as the main oxygen source of the city, are highly damaged. This study aims to examine the temporal impact of rapid urban growth on forest cover in the mega city of Istanbul between the years of 1987- 2007. Spatial distribution of forests and their temporal changes were analyzed and presented by using Remote Sensing and Geographical Information Systems (GIS) in the 6 different districts of Istanbul selected from both sides of the Bosphorus. While Fatih District was selected as the historical section of the European side of Istanbul, Bagcilar and Büyükcekmece Districts were chosen as the newly urbanized areas. In the Asian side of the city, Kadikoy District was chosen as an example for the old settlement of the city and the Maltepe and Sultanbeyli Districts were selected as the rapidly urbanized districts for the study. VIS model is applied to differentiate urban land from rural land and to conduct urban morphology of the developed areas under three basic components of Vegetation-Impervious land and Soil. In this study, Vegetation, Impervious

  19. Combined operando Raman/UV-Vis-NIR spectroscopy as a tool to study supported metal oxide catalysts at work

    NARCIS (Netherlands)

    Tinnemans, Stanislaus Josephus

    2006-01-01

    A novel set-up has been developed in which two complementary spectroscopic techniques, namely operando Raman and UV-Vis-NIR spectroscopy, are combined. With this set-up it is possible to characterize catalytic materials under reaction conditions (high temperature, normal pressure) and in this way on

  20. Using UV-VIS spectrophotometry for determining ecotoxicity of selected non-steroidal anti-inflammatory drugs

    OpenAIRE

    Čapka, L. (Lukáš); Zlámalová Gargošová, H.; Vávrová, M.

    2015-01-01

    This paper presents the use of UV-VIS spectrophotometry as a means of determining ecotoxicity. The method is based on spectrophotometric measuring of micro-algae Pseudokirchneriella subcapitata in water suspension. Six non-steroidal anti-inflammatory drugs were selected as target compounds.

  1. UV-Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 2: selected applications.

    Science.gov (United States)

    Antosiewicz, Jan M; Shugar, David

    2016-06-01

    In Part 2 we discuss application of several different types of UV-Vis spectroscopy, such as normal, difference, and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, of the side-chain of tyrosine residues in different molecular environments. We review the ways these spectroscopies can be used to probe complex protein structures.

  2. Development of an Age Band on the ManuVis for 3-Year-Old Children with Visual Impairments

    NARCIS (Netherlands)

    Reimer, A.M.; Barsingerhorn, A.D.; Overvelde, A.; Nijhuis-Van der Sanden, M.W.G.; Boonstra, F.N.; Cox, R.F.A.

    2017-01-01

    AIM: To compare fine motor performance of 3-year-old children with visual impairment with peers having normal vision, to provide reference scores for 3-year-old children with visual impairment on the ManuVis, and to assess inter-rater reliability. METHOD: 26 children with visual impairment (mean

  3. Vis-A-Ware: Integrating Spatial and Non-Spatial Visualization for Visibility-Aware Urban Planning.

    Science.gov (United States)

    Ortner, Thomas; Sorger, Johannes; Steinlechner, Harald; Hesina, Gerd; Piringer, Harald; Groller, Eduard

    2017-02-01

    3D visibility analysis plays a key role in urban planning for assessing the visual impact of proposed buildings on the cityscape. A call for proposals typically yields around 30 candidate buildings that need to be evaluated with respect to selected viewpoints. Current visibility analysis methods are very time-consuming and limited to a small number of viewpoints. Further, analysts neither have measures to evaluate candidates quantitatively, nor to compare them efficiently. The primary contribution of this work is the design study of Vis-A-Ware, a visualization system to qualitatively and quantitatively evaluate, rank, and compare visibility data of candidate buildings with respect to a large number of viewpoints. Vis-A-Ware features a 3D spatial view of an urban scene and non-spatial views of data derived from visibility evaluations, which are tightly integrated by linked interaction. To enable a quantitative evaluation we developed four metrics in accordance with experts from urban planning. We illustrate the applicability of Vis-A-Ware on the basis of a use case scenario and present results from informal feedback sessions with domain experts from urban planning and development. This feedback suggests that Vis-A-Ware is a valuable tool for visibility analysis allowing analysts to answer complex questions more efficiently and objectively.

  4. Inline UV-Vis spectroscopy to monitor and optimize cleaning-in-place (CIP) of whey filtration plants

    DEFF Research Database (Denmark)

    Berg, Thilo Heinz Alexander; Ottosen, Niels; van der Berg, Franciscus Winfried J.

    2017-01-01

    transferred to a pilot plant equipped with inline UV-Vis spectroscopy on both the retentate and permeate side. Then the dynamics of multiple fouling and cleaning of these membranes were investigated. The results indicate that the first CIP step, caustic cleaning could be shortened and possibly reduced...

  5. In situ, rapid, and temporally resolved measurements of cellulase adsorption onto lignocellulosic substrates by UV-vis spectrophotometry

    Science.gov (United States)

    Hao Liu; J. Y. Zhu; X. S. Chai

    2011-01-01

    This study demonstrated two in situ UV-vis spectrophotometric methods for rapid and temporally resolved measurements of cellulase adsorption onto cellulosic and lignocellulosic substrates during enzymatic hydrolysis. The cellulase protein absorption peak at 280 nm was used for quantification. The spectral interferences from light scattering by small fibers (fines) and...

  6. Prediction of quality attributes of chicken breast fillets by using Vis/NIR spectroscopy combined with factor analysis method

    Science.gov (United States)

    Visible/near-infrared (Vis/NIR) spectroscopy with wavelength range between 400 and 2500 nm combined with factor analysis method was tested to predict quality attributes of chicken breast fillets. Quality attributes, including color (L*, a*, b*), pH, and drip loss were analyzed using factor analysis ...

  7. NIR-Vis-UV Light-Responsive Actuator Films of Polymer-Dispersed Liquid Crystal/Graphene Oxide Nanocomposites.

    Science.gov (United States)

    Cheng, Zhangxiang; Wang, Tianjie; Li, Xiao; Zhang, Yihe; Yu, Haifeng

    2015-12-16

    To take full advantage of sunlight for photomechanical materials, NIR-vis-UV light-responsive actuator films of polymer-dispersed liquid crystal (PDLC)/graphene oxide (GO) nanocomposites were fabricated. The strategy is based on phase transition of LCs from nematic to isotropic phase induced by combination of photochemical and photothermal processes in the PDLC/GO nanocomposites. Upon mechanical stretching of the film, both topological shape change and mesogenic alignment occurred in the separated LC domains, enabling the film to respond to NIR-vis-UV light. The homodispersed GO flakes act as photoabsorbent and nanoscale heat source to transfer NIR or VIS light into thermal energy, heating the film and photothermally inducing phase transition of LC microdomains. By utilizing photochemical phase transition of LCs upon UV-light irradiation, one azobenzene dye was incorporated into the LC domains, endowing the nanocomposite films with UV-responsive property. Moreover, the light-responsive behaviors can be well-controlled by adjusting the elongation ratio upon mechanical treatment. The NIR-vis-UV light-responsive PDLC/GO nanocomposite films exhibit excellent properties of easy fabrication, low-cost, and good film-forming and mechanical features, promising their numerous applications in the field of soft actuators and optomechanical systems driven directly by sunlight.

  8. Evaluation of factors in development of Vis/NIR spectroscopy models for discriminating PSE, DFD and normal broiler breast meat

    Science.gov (United States)

    1. To evaluate the performance of visible and near-infrared (Vis/NIR) spectroscopic models for discriminating true pale, soft and exudative (PSE), normal and dark, firm and dry (DFD) broiler breast meat in different conditions of preprocessing methods, spectral ranges, characteristic wavelength sele...

  9. XRD and UV-Vis diffuse reflectance analysis of CeO 2-ZrO 2 solid ...

    Indian Academy of Sciences (India)

    The products were characterized by XRD and UV-Vis-NIR diffuse reflectance spectroscopy. The materials are crystalline in nature and the lattice parameters of the solid solution series follow Vegard's law. Diffuse reflectance spectra of the solid solutions in the UV region show two intense bands at 250 and 297 nm which are ...

  10. Late Viséan/early Serpukhovian conodont succession from the Triollo section, Palencia (Cantabrian Mountains, Spain)

    NARCIS (Netherlands)

    Nemyrovska, T.I.; Samankassou, E.

    2005-01-01

    The present study reports upon the conodont faunas of the uppermost lower Viséan (Carrión unit) through the lower Serpukhovian (Peña unit) deep water Triollo section, Cantabrian Mountains, Palencia, Spain. The condensed succession of grey, laminate, nodular and cherty limestones with marl

  11. Importance of Vibronic Effects in the UV-Vis Spectrum of the 7,7,8,8-Tetracyanoquinodimethane Anion.

    Science.gov (United States)

    Tapavicza, Enrico; Furche, Filipp; Sundholm, Dage

    2016-10-11

    We present a computational method for simulating vibronic absorption spectra in the ultraviolet-visible (UV-vis) range and apply it to the 7,7,8,8-tetracyanoquinodimethane anion (TCNQ(-)), which has been used as a ligand in black absorbers. Gaussian broadening of vertical electronic excitation energies of TCNQ(-) from linear-response time-dependent density functional theory produces only one band, which is qualitatively incorrect. Thus, the harmonic vibrational modes of the two lowest doublet states were computed, and the vibronic UV-vis spectrum was simulated using the displaced harmonic oscillator approximation, the frequency-shifted harmonic oscillator approximation, and the full Duschinsky formalism. An efficient real-time generating function method was implemented to avoid the exponential complexity of conventional Franck-Condon approaches to vibronic spectra. The obtained UV-vis spectra for TCNQ(-) agree well with experiment; the Duschinsky rotation is found to have only a minor effect on the spectrum. Born-Oppenheimer molecular dynamics simulations combined with calculations of the electronic excitation energies for a large number of molecular structures were also used for simulating the UV-vis spectrum. The Born-Oppenheimer molecular dynamics simulations yield a broadening of the energetically lowest peak in the absorption spectrum, but additional vibrational bands present in the experimental and simulated quantum harmonic oscillator spectra are not observed in the molecular dynamics simulations. Our results underline the importance of vibronic effects for the UV-vis spectrum of TCNQ(-), and they establish an efficient method for obtaining vibronic spectra using a combination of linear-response time-dependent density functional theory and a real-time generating function approach.

  12. ElVisML: an open data format for the exchange and storage of electrophysiological data in ophthalmology.

    Science.gov (United States)

    Strasser, Torsten; Peters, Tobias; Jägle, Herbert; Zrenner, Eberhart

    2018-02-01

    The ISCEV standards and recommendations for electrophysiological recordings in ophthalmology define a set of protocols with stimulus parameters, acquisition settings, and recording conditions, to unify the data and enable comparability of results across centers. Up to now, however, there are no standards to define the storage and exchange of such electrophysiological recordings. The aim of this study was to develop an open standard data format for the exchange and storage of visual electrophysiological data (ElVisML). We first surveyed existing data formats for biomedical signals and examined their suitability for electrophysiological data in ophthalmology. We then compared the suitability of text-based and binary formats, as well as encoding in Extensible Markup Language (XML) and character/comma-separated values. The results of the methodological consideration led to the development of ElVisML with an XML-encoded text-based format. This allows referential integrity, extensibility, the storing of accompanying units, as well as ensuring confidentiality and integrity of the data. A visualization of ElVisML documents (ElVisWeb) has additionally been developed, which facilitates the exchange of recordings on mailing lists and allows open access to data along with published articles. The open data format ElVisML ensures the quality, validity, and integrity of electrophysiological data transmission and storage as well as providing manufacturer-independent access and long-term archiving in a future-proof format. Standardization of the format of such neurophysiology data would promote the development of new techniques and open software for the use of neurophysiological data in both clinic and research.

  13. Simulated In Situ Determination of Soil Profile Organic and Inorganic Carbon With LIBS and VisNIR

    Science.gov (United States)

    Bricklemyer, R. S.; Brown, D. J.; Clegg, S. M.; Barefield, J. E.

    2008-12-01

    There is growing need for rapid, accurate, and inexpensive methods to measure, and verify soil organic carbon (SOC) change for national greenhouse gas accounting and the development of a soil carbon trading market. Laser Induced Breakdown Spectroscopy (LIBS) and Visible and Near Infrared Spectroscopy (VisNIR) are complementary analytical techniques that have the potential to fill that need. The LIBS method provides precise elemental analysis of soils, but generally cannot distinguish between organic C and inorganic C. VisNIR has been established as a viable technique for measuring soil properties including SOC and inorganic carbon (IC). As part of the Big Sky Carbon Sequestration Regional Partnership, 240 intact core samples (3.8 x 50 cm) have been collected from six agricultural fields in north central Montana, USA. Each of these core samples were probed concurrently with LIBS and VisNIR at 2.5, 7.5, 12.5, 17.5, 22.5, 27.5, 35 and 45 cm (+/- 1.5 cm) depths. VisNIR measurements were taken using an Analytical Spectral Devices (ASD, Boulder, CO, USA) Agrispec spectrometer to determine the partition of SOC vs. IC in the samples. The LIBS scans were collected with the LANL LIBS Core Scanner Instrument which collected the entire 200 - 900 nm plasma emission including the 247.8 nm carbon emission line. This instrument also collected the emission from the elements typically found in inorganic carbon (Ca and Mg) and organic carbon (H, O, and N). Subsamples of soil (~ 4 g) were taken from interrogation points for laboratory determination of SOC and IC. Using this analytical data, we constructed several full spectrum multivariate VisNIR/LIBS calibration models for SOC and IC. These models were then applied to independent validation cores for model evaluation.

  14. UV–Vis Light-induced Aging of Titan’s Haze and Ice

    Science.gov (United States)

    Couturier-Tamburelli, Isabelle; Piétri, Nathalie; Le Letty, Vincent; Chiavassa, Thierry; Gudipati, Murthy

    2018-01-01

    The study of the photochemical aging of aerosols is an important tool for understanding Titan’s stratosphere/troposphere composition and evolution, particularly the haze. Laboratory simulations of the photoreactivity of the haze aerosol analogs provide insight into the photochemical evolution of Titan’s atmosphere at and below the haze layers. Here we use experimental simulations to investigate the evolution of the laboratory analogs of these organic aerosols under ultraviolet (UV)–visible (Vis) photons, which make it through the haze layers during their sedimentation process. We present experimental results for the aging of Titan’s aerosol analogs obtained from two dominant nitrogen-containing organics, HC3N and HCN, under simulated Titan atmospheric conditions (photons and temperature). We report that volatile nitriles condensed on haze particles could be incorporated through photochemistry and provide one such sink mechanism for nitrile compounds. We provide laboratory evidence that the organic aerosols could photochemically evolve during their sedimentation through Titan’s atmosphere.

  15. Rendering and Compositing Infrastructure Improvements to VisIt for Insitu Rendering

    Energy Technology Data Exchange (ETDEWEB)

    Loring, Burlen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ruebel, Oliver [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-01-28

    Compared to posthoc rendering, insitu rendering often generates larger numbers of images, as a result rendering performance and scalability are critical in the insitu setting. In this work we present improvements to VisIt's rendering and compositing infrastructure that deliver increased performance and scalability in both posthoc and insitu settings. We added the capability for alpha blend compositing and use it with ordered compositing when datasets have disjoint block domain decomposition to optimize the rendering of transparent geometry. We also made improvements that increase overall efficiency by reducing communication and data movement and have addressed a number of performance issues. We structured our code to take advantage of SIMD parallelization and use threads to overlap communication and compositing. We tested our improvements on a 20 core workstation using 8 cores to render geometry generated from a $256^3$ cosmology dataset and on a Cray XC31 using 512 cores to render geometry generated from a $2000^2 \\times 800$ plasma dataset. Our results show that ordered compositing provides a speed up of up to $4 \\times$ over the current sort first strategy. The other improvements resulted in modest speed up with one notable exception where we achieve up to $40 \\times$ speed up of rendering and compositing of opaque geometry when both opaque and transparent geometry are rendered together. We also investigated the use of depth peeling, but found that the implementation provided by VTK is substantially slower,both with and without GPU acceleration, than a local camera order sort.

  16. Optofluidic UV-Vis spectrophotometer for online monitoring of photocatalytic reactions

    Science.gov (United States)

    Wang, Ning; Tan, Furui; Zhao, Yu; Tsoi, Chi Chung; Fan, Xudong; Yu, Weixing; Zhang, Xuming

    2016-01-01

    On-chip integration of optical detection units into the microfluidic systems for online monitoring is highly desirable for many applications and is also well in line with the spirit of optofluidics technology–fusion of optics and microfluidics for advanced functionalities. This paper reports the construction of a UV-Vis spectrophotometer on a microreactor, and demonstrates the online monitoring of the photocatalytic degradations of methylene blue and methyl orange under different flow rates and different pH values by detecting the intensity change and/or the peak shift. The integrated device consists of a TiO2-coated glass substrate, a PDMS micro-sized reaction chamber and two flow cells. By comparing with the results of commercial equipment, we have found that the measuring range and the sensitivity are acceptable, especially when the transmittance is in the range of 0.01–0.9. This integrated optofluidic device can significantly cut down the test time and the sample volume, and would provide a versatile platform for real-time characterization of photochemical performance. Moreover, its online monitoring capability may enable to access the usually hidden information in biochemical reactions like intermediate products, time-dependent processes and reaction kinetics. PMID:27352840

  17. A combined experimental (IR, Raman and UV-Vis) and quantum chemical study of canadine

    Science.gov (United States)

    Joshi, Bhawani Datt; Srivastava, Anubha; Tandon, Poonam; Jain, Sudha; Ayala, A. P.

    2018-02-01

    Plant based natural products cover a major sector of the medicinal field, as such focus on plant research has been increased all over the world. As an attempt to aid that research, we have performed structural and spectroscopic analysis of a natural product, an alkaloid: canadine. Both ab initio Hartree-Fock (HF) and density functional theory (DFT) employing B3LYP using 6-311 ++G(d,p) basis set were used for the calculations. The calculated vibrational frequencies were scaled and compared with the experimental infrared and Raman spectra. The complete vibrational assignments were made using potential energy distribution. The structure-activity relation has also been interpreted by mapping electrostatic potential surface and evaluating the reactivity descriptors, which are valuable information for quality control of medicines and drug-receptor interactions. Natural bond orbital analysis has also been performed to understand the stability and hyperconjugative interactions of the molecule. Furthermore, UV-Vis spectra have been recorded in an ethanol solvent (EtOH) and the electronic property has been analyzed employing TD-DFT for both gaseous and solvent phase. The HOMO and LUMO calculation with their energy gap show that charge transfer occurs within the molecule. Additionally, the nonlinear optical properties of the title compound have been interpreted that predicts it's the best candidate for the NLO materials.

  18. UV-VIS Spectroscopy Applied to Stratospheric Chemistry, Methods and Results

    Energy Technology Data Exchange (ETDEWEB)

    Karlsen, K.

    1996-03-01

    This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. Numerous observations and modeling have shown with a very high degree of certainty that the man-made emissions of chlorofluorocarbons (CFC) and halons are responsible for the Antarctica ozone hole. It is also evident that the ozone layer of the Northern Hemisphere has suffered a certain decline over the last 10-15 years, possibly because of CFC and halons. 20-30% of the observed reduction is ascribed to coupled chlorine and bromine chemistry via a catalytic cycle resulting in the net conversion of 2O{sub 3} to 3O{sub 2}. But the details are not fully understood. The author plans to assemble a UV-VIS spectrometer for measuring the species OClO and BrO and to compare and discuss measured diurnal variations of OClO and BrO with model calculations. The use of Differential Optical Absorption Spectroscopy (DOAS) is discussed and some results from late 1995 presented. 6 refs., 2 figs.

  19. Determination of solar optical properties of transparent polymer films using UV/vis spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oreski, G.; Tscharnuter, D. [Polymer Competence Center Leoben GmbH, Parkstrasse 11, A-8700 Leoben (Austria); Wallner, G.M. [Institute of Materials Science and Testing of Plastics, University of Leoben (Austria)

    2010-05-15

    In this paper, 4- and 5-flux models were implemented and used for the determination of absorption and scattering coefficients of transparent polymer films by UV/vis/NIR spectroscopy. The models were applied for a systematic characterization of polar ethylene copolymer films in the solar radiation range. The investigated ethylene copolymer films were highly transparent in the solar range of radiation, with hemispheric transmittance values above 91% and hemispheric reflectance values of about 8%. Both models revealed a significant forward scattering behavior of the films. The 4-flux model fitted hemispheric and diffuse transmittance far better than the 5-flux model. Hemispheric reflectance values were overestimated by both models. Similar absorption coefficient values ranging from 0.4 to 0.6 cm{sup -1} were obtained for all investigated films. While ethylene(acrylic acid/butylacrylate) terpolymer showed the lowest scattering coefficient (10.9 (5-flux) and 6.8 cm{sup -1} (4-flux)), the highest scattering coefficient (26.2 (5-flux) and 35.2 cm{sup -1} (4-flux)) was found for ethylene(butylacrylate) copolymer. (author)

  20. Course of poly(4-aminodiphenylamine)/Ag nanocomposite formation through UV-vis spectroscopy

    Science.gov (United States)

    Thanjam, Starlet; Philips, M. Francklin; Komathi, S.; Manisankar, P.; Sivakumar, C.; Gopalan, A.; Lee, Kwang-Pill

    2011-09-01

    Kinetics of chemical oxidative polymerization of 4-aminodiphenylamine (4ADPA) was followed in aqueous 1 M p-toluene sulfonic acid (p-TSA) using silver nitrate (AgNO 3) as an oxidant by UV-vis spectroscopy. The medium was found to be clear and homogeneous during the course of polymerization. The absorbances corresponding to the intermediate and the polymer were followed for different concentrations of 4ADPA and AgNO 3 and at different reaction time. The appearance of a band around 450 nm during the initial stages of polymerization corresponds to the plasmon resonance formed by the reduction of Ag + ions. Rate of poly(4-aminodiphenylamine)/Ag nanocomposite ( RP4ADPA/AgNC) was determined for various reaction conditions. RP4ADP/AgNC showed second order power dependence on 4ADPA and first order dependence on AgNO 3. The observed order dependences of 4ADPA and AgNO 3 on the formation of P4ADPA/AgNC were used to deduce a rate equation for the reaction. Rate constant for the reaction was determined through different approaches. The good agreement between the rate constants obtained through different approaches justifies the selection of rate equation.

  1. Study of PVDF/Graphene oxide nanocomposites by UV-Vis analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Juliana V., E-mail: jvp@cdtn.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Nascimento, Jefferson P.; Furtado, Clascidia A.; Faria, Luiz O. de, E-mail: farialo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    In this work we have prepared nanocomposites made by mixing Poly (vinylidene fluoride) [PVDF] and grapheme oxide nanosheets (GO) aiming to find dosimetric properties for applications in high dose dosimetry. Graphene Oxides (GO) nanosheets were synthesized by the Hummers method, using graphite supplied by Aldrich as the starting material. Nanocomposites were produced by mixing solved PDVF in DMAc with GO dispersed in an aqueous solution by sonication. The samples were irradiated with a Co-60 source at constant dose rate (12 kGy/h), with doses ranging from 50 to 1,000 kGy. The UV-Vis and spectrophotometry have been used to monitor the appearing of C=C conjugated bonds and radio-oxidation of carbon (C=O). The PVDF/OG nanocomposites prepared with 1.88 at.% of OG presented the best dosimetric properties. In this material, UVVis spectrometry has revealed that the absorbance intensities at 250 nm can be used for high dosimetry purposes for gamma doses ranging from 100 to 750 kGy. In this range, it is possible to observe a linear relationship between Abs and Dose. (author)

  2. Automated Cart with VIS/NIR Hyperspectral Reflectance and Fluorescence Imaging Capabilities

    Directory of Open Access Journals (Sweden)

    Alan M. Lefcourt

    2016-12-01

    Full Text Available A system to take high-resolution Visible/Near Infra-Red (VIS/NIR hyperspectral reflectance and fluorescence images in outdoor fields using ambient lighting or a pulsed laser (355 nm, respectively, for illumination purposes was designed, built, and tested. Components of the system include a semi-autonomous cart, a gated-intensified camera, a spectral adapter, a frequency-triple Nd:YAG (Neodymium-doped Yttrium Aluminium Garnet laser, and optics to convert the Gaussian laser beam into a line-illumination source. The front wheels of the cart are independently powered by stepper motors that support stepping or continuous motion. When stepping, a spreadsheet is used to program parameters of image sets to be acquired at each step. For example, the spreadsheet can be used to set delays before the start of image acquisitions, acquisition times, and laser attenuation. One possible use of this functionality would be to establish acquisition parameters to facilitate the measurement of fluorescence decay-curve characteristics. The laser and camera are mounted on an aluminum plate that allows the optics to be calibrated in a laboratory setting and then moved to the cart. The system was validated by acquiring images of fluorescence responses of spinach leaves and dairy manure.

  3. Quantitative characterization of the colloidal stability of metallic nanoparticles using UV-vis absorbance spectroscopy.

    Science.gov (United States)

    Ray, Tyler R; Lettiere, Bethany; de Rutte, Joseph; Pennathur, Sumita

    2015-03-31

    Plasmonic nanoparticles are used in a wide variety of applications over a broad array of fields including medicine, energy, and environmental chemistry. The continued successful development of this material class requires the accurate characterization of nanoparticle stability for a variety of solution-based conditions. Although many characterization methods exists, there is an absence of a unified, quantitative means for assessing the colloidal stability of plasmonic nanoparticles. We present the particle instability parameter (PIP) as a robust, quantitative, and generalizable characterization technique based on UV-vis absorbance spectroscopy to characterize colloidal instability. We validate PIP performance with both traditional and alternative characterization methods by measuring gold nanorod instability in response to different salt (NaCl) concentrations. We further measure gold nanorod stability as a function of solution pH, salt, and buffer (type and concentration), nanoparticle concentration, and concentration of free surfactant. Finally, these results are contextualized within the literature on gold nanorod stability to establish a standardized methodology for colloidal instability assessment.

  4. Study on fast discrimination of varieties of yogurt using Vis/NIR-spectroscopy

    Science.gov (United States)

    He, Yong; Feng, Shuijuan; Deng, Xunfei; Li, Xiaoli

    2006-09-01

    A new approach for discrimination of varieties of yogurt by means of VisINTR-spectroscopy was present in this paper. Firstly, through the principal component analysis (PCA) of spectroscopy curves of 5 typical kinds of yogurt, the clustering of yogurt varieties was processed. The analysis results showed that the cumulate reliabilities of PC1 and PC2 (the first two principle components) were more than 98.956%, and the cumulate reliabilities from PC1 to PC7 (the first seven principle components) was 99.97%. Secondly, a discrimination model of Artificial Neural Network (ANN-BP) was set up. The first seven principles components of the samples were applied as ANN-BP inputs, and the value of type of yogurt were applied as outputs, then the three-layer ANN-BP model was build. In this model, every variety yogurt includes 27 samples, the total number of sample is 135, and the rest 25 samples were used as prediction set. The results showed the distinguishing rate of the five yogurt varieties was 100%. It presented that this model was reliable and practicable. So a new approach for the rapid and lossless discrimination of varieties of yogurt was put forward.

  5. Simultaneous Determination of Caffeine and Chlorogenic Acids in Green Coffee by UV/Vis Spectroscopy

    Directory of Open Access Journals (Sweden)

    G. Navarra

    2017-01-01

    Full Text Available A simple method for the simultaneous determination of caffeine and chlorogenic acids content in green coffee was reported. The method was based on the use of UV/Vis absorption. It is relevant that the quantification of both caffeine and chlorogenic acids was performed without their preliminary chemical separation despite their spectral overlap in the range 250–350 nm. Green coffee was extracted with 70% ethanol aqueous solution; then the solution was analyzed by spectroscopy. Quantitative determination was obtained analytically through deconvolution of the absorption spectrum and by applying the Lambert-Beer law. The bands used for the deconvolution were the absorption bands of both caffeine and chlorogenic acids standards. The molar extinction coefficients for caffeine and chlorogenic acid in ethanol solution at 70% were calculated by using the chemical standards; the estimated values were ε(272 nm=12159±97 M−1 cm−1 for caffeine and ε(330 nm=27025±190 M−1 cm−1 for chlorogenic acids molecules, respectively. The estimate of concentration values was in agreement with the one obtained by High Performance Liquid Chromatography quantification. The method is fast and simple and allows us to realize routine controls during the coffee production. In addition, it could be applied on roasted coffee and espresso coffee.

  6. Universal calibration facility for VIS-TIR wide-angle videospectrometric airborne sensors

    Science.gov (United States)

    Oertel, Dieter; Morozova, Svetlana P.

    1994-06-01

    The European Union and DLR are funding a new 79-channel airborne imaging spectrometer: DAIS-7915, which is built by GER Corporation. Based on the requirements for ground calibration of the DAIS-7915, a Universal Calibration Facility (UCF) for VIS-TIR wide-angel videospectrometric airborne sensors has been developed at the DLR-Institute of Optoelectronic. The spectral coverage of the UCF is 0.4 - 14.5 micrometers . The UCF consists of the spectrometric-geometric calibration part (SCP), the relative diffuse radiometric source (RDRS), the thermal absolute calibration part (TACP) and the absolute radiometric calibration part (ARCP). The SCP, RDRS, and TACP can be used for laboratory calibration as well as for hangar calibration of the sensor installed in the aircraft. The ARCP consists of an integrating sphere with 165 cm diameter and an opening of 40 X 55 cm2. The sphere is intercalibrated by means of an absolute diffuse source (ADS) and a spectro- radiometer. The ADS has been recognized and admitted for application as a reference instrument for measuring the spectral radiance in the wavelength region of 0.4 - 2.5 micrometers .

  7. O teste-C de leitura: uma visão panorâmica

    Directory of Open Access Journals (Sweden)

    Grotjahn, Rüdiger

    1991-01-01

    Full Text Available O presente artigo dá uma visão geral sobre o campo de pesquisa do teste-C, uma variante do procedimento cloze. Primeiro, pormenorizará uma breve referência sobre o principio cloze e a teoria básica da redundância reduzida. Depois, segue, uma descrição e discussão crítica dos clássicos princípios de construção do Teste-C. A seguir, serão esboçados o desenvolvimento e a análise do Teste-C, assim como o seu emprego na pesquisa e na prática. Segue uma discussão da confiabilidade, objetividade, economia e validade do Teste-C, em que reside o ponto principal no âmbito da validade. Em contato com estes dados aprofundaremos relativa e minuciosamente a questão, se o Teste-C (também um teste de leitura. Neste contexto também serão referidas algumas pesquisas empíricas, que o autor realizou em resposta à questão

  8. Photodegradation study of nystatin by UV-Vis spectrophotometry and chemometrics modeling.

    Science.gov (United States)

    Hemmateenejad, Bahram; Nekoeinia, Mohsen; Absalan, Ghodratollah; Ansari, Mehdi

    2014-01-01

    Nystatin, one of the tetraene antifungal antibiotics, is very sensitive to light. Thus, when nystatin is exposed to natural daylight, it is photodegraded to products of lower biological activity. In this work, the photodegradation kinetics of nystatin was monitored by a UV-Vis spectrophotometry method. The absorbance spectra of the nystatin, exposed to a 366 nm UV lamp, were recorded at different periods of time. By application of factor analysis to the absorbance data matrix, three absorbing chemical species, coexisting in the reaction system, were detected. The soft-modeling multivariate curve resolution-alternating least squares analysis of the evolutionary absorbance data revealed that nystatin undergoes photodegradation in a two-step consecutive manner. Hard-modeling data analysis suggested that reaction has first-order kinetics in the first step and zero-order kinetics in the second step. The reaction rate constants of the first and second steps were estimated as 0.0929 (+/-0.0076) and 0.0052 (+/-0.0016)/min, respectively. Finally, the pure spectra of the resolved chemical species were calculated.

  9. Stationary cuvette: a new approach to obtaining analytical curves by UV-VIS spectrophotometry.

    Science.gov (United States)

    Silva, K G H; Júnior, F H Xavier; Farias, I E G; Silva, A K A; Neto, J A Caldas; Souza, L C A; Santiago, R R; Júnior, F Alexandrino; Júnior, T Nagashima; Soares, L A L; Santos-Magalhães, N S; Egito, E S T

    2009-01-01

    Investigations in the field of pharmaceutical analysis and quality control of medicines require analytical procedures that achieve suitable performance. An analytical curve is one of the most important steps in the chemical analysis presenting a direct relationship to features such as linearity. This study has the aim of developing a new methodology, the stationary cuvette, to derive analytical curves by spectroscopy for drug analysis. The method consists basically of the use of a cuvette with a path length of 10 cm, containing a constant volume of solvent in which increasing amounts of a stock solution of the sample are added, droplet by droplet. After each addition, the cuvette is stirred and the absorbance is measured. This procedure was compared with the currently used methodology, which requires a labour-intensive dilution process, and possible sources of variation between them were evaluated. The results demonstrated that the proposed technique presented high sensitivity and similar reproducibility compared with the conventional methodology. In addition, a number of advantages were observed, such as user-friendliness, cost-effectiveness, accuracy, precision and robustness. The stationary cuvette approach may be considered to be an appropriate alternative to derive analytical curves for analysing drug content in raw materials and medicines through UV-VIS spectrophotometry.

  10. John Langshaw Austin e a Visão Performativa da Linguagem

    Directory of Open Access Journals (Sweden)

    OTTONI Paulo

    2002-01-01

    Full Text Available Austin surge no cenário da discussão sobre a linguagem num momento histórico preciso e será o porta-voz de todo um processo histórico da filosofia contemporânea ao revolucionar não só a filosofia analítica naquele momento, como também a lingüística enquanto ciência autônoma. Neste artigo, questiono o caminho e a supremacia do positivismo lógico nos estudos da linguagem, procurando analisar qual é o papel de Austin, neste processo, através da discussão dos conceitos de performativo, de ato de fala, de uptake e de ilocucionário que estão vinculados na sua obra de modo muito especial. Parto da hipótese de que Austin é um "desconstrutor". Denomino sua abordagem da linguagem de "visão performativa", pelo fato de haver nas suas reflexões um espaço conflitante que põe em discussão as fronteiras entre a filosofia e a lingüística nos estudos da linguagem.

  11. Analysis of organophosphate-Zn metalloporphyrin interactions via UV-vis spectroscopy and molecular modeling.

    Science.gov (United States)

    Rompoti, A; Dalal, N; Athanasopoulos, D; Rutan, S; Helburn, R

    2015-01-25

    UV-vis absorption spectra of zinc tetraphenylporphine (ZnTPP) on interaction with six organophosphorus (OP) compounds in cyclohexane were compared using ab initio methods and the molecular and solvation ligand descriptors π(*), Vx, and σ. OPs with polarizable hydrocarbon substituents in the homologous series tri-ethyl, -pentyl, -octyl, and -phenyl phosphates and the toxicologically relevant methyl paraoxon (1a-e) each gave a red shift in the Soret band (λsor) of ZnTPP in the range of 8-10 nm. Sensitivity as ΔAsor-b/Δug OP for the spectral band of the ligand bound ZnTPP (λsor-b) decreased with increasing extent of alkyl and aromatic substitution. Calculated and combined energies for OP and ZnTPP examined as a function of distance (Å) between ligand and porphyrin center suggest increased steric crowding with increasing Vx, and aromatic content of the OP. Spectrally fitted K1:1 and ΔAsor-b/ug OP each vary exponentially with Vx/σ. Lack of a red shift in λsor-b where ZnTPP was titrated with the toxic diethyl chlorophosphate (1g) is consistent with a model in which the magnitude of ΔEsor is proportional to the donor capacity of the phosphoryl-O ligand. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Combined characterization of bovine polyhemoglobin microcapsules by UV-Vis absorption spectroscopy and cyclic voltammetry.

    Science.gov (United States)

    Knirsch, Marcos Camargo; Dell'Anno, Filippo; Salerno, Marco; Larosa, Claudio; Polakiewicz, Bronislaw; Eggenhöffner, Roberto; Converti, Attilio

    2017-03-01

    Polyhemoglobin produced from pure bovine hemoglobin by reaction with PEG bis(N-succynimidil succinate) as a cross-linking agent was encapsulated in gelatin and dehydrated by freeze-drying. Free carboxyhemoglobin and polyhemoglobin microcapsules were characterized by UV-Vis spectroscopy in the absorption range 450-650 nm and cyclic voltammetry in the voltage range from -0.8 to 0.6 mV to evaluate the ability to break the bond with carbon monoxide and to study the carrier's affinity for oxygen, respectively. SEM used to observe the shape of cross-linked gelatin-polyhemoglobin microparticles showed a regular distribution of globular shapes, with mean size of ~750 nm, which was ascribed to gelatin. Atomic absorption spectroscopy was also performed to detect iron presence in microparticles. Cyclic voltammetry using an Ag-AgCl electrode highlighted characteristic peaks at around -0.6 mV that were attributed to reversible oxygen bonding with iron in oxy-polyhemoglobin structure. These results suggest this technique as a powerful, direct and alternative method to evaluate the extent of hemoglobin oxygenation.

  13. Thermal edible oil evaluation by UV-Vis spectroscopy and chemometrics.

    Science.gov (United States)

    Gonçalves, Rhayanna P; Março, Paulo H; Valderrama, Patrícia

    2014-11-15

    Edible oils such as colza, corn, sunflower, soybean and olive were analysed by UV-Vis spectroscopy and Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS). When vegetable oils were heated at high temperatures (frying), oxidation products were formed which were harmful to human health in addition to degrading the antioxidants present, and this study aimed to evaluate tocopherol (one antioxidant present in oils) and the behaviour of oxidation products in edible oils. The MCR-ALS results showed that the degradation started at 110°C and 85°C, respectively, for sunflower and colza oils, while tocopherol concentration decreased and oxidation products increased starting at 70°C in olive oil. In soybean and corn oils, tocopherol concentration started to decrease and oxidation products increased at 50°C. The results suggested that sunflower, colza and olive oils offered more resistance to increasing temperatures, while soybean and corn oils were less resistant. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Measurement of Heme Ruffling Changes in MhuD Using UV-vis Spectroscopy.

    Science.gov (United States)

    Graves, Amanda B; Graves, Max T; Liptak, Matthew D

    2016-04-28

    For decades it has been known that an out-of-plane ruffling distortion of heme perturbs its UV-vis absorption (Abs) spectrum, but whether increased ruffling induces a red or blue shift of the Soret band has remained a topic of debate. This debate has been resolved by the spectroscopic and computational characterization of Mycobacterium tuberculosis MhuD presented here, an enzyme that converts heme, oxygen, and reducing equivalents to nonheme iron and mycobilin. W66F and W66A MhuD have been characterized using (1)H nuclear magnetic resonance, Abs, and magnetic circular dichroism spectroscopies, and the data have been used to develop an experimentally validated theoretical model of ruffled, ferric heme. The PBE density functional theory (DFT) model that has been developed accurately reproduces the observed spectral changes from wild type enzyme, and the underlying quantum mechanical origins of these ruffling-induced changes were revealed by analyzing the PBE DFT description of the electronic structure. Small amounts of heme ruffling have no influence on the energy of the Q-band and blue-shift the Soret band due to symmetry-allowed mixing of the Fe 3dxy and porphyrin a2u orbitals. Larger amounts of ruffling red-shift both the Q and Soret bands due to disruption of π-bonding within the porphyrin ring.

  15. Implante coclear em crianças: a visão dos pais

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida Rissi Yamanaka

    Full Text Available O objetivo do estudo foi analisar a visão que os pais têm do implante coclear, isto é, as informações que eles têm a respeito do implante, os riscos, os benefícios e suas expectativas em relação ao futuro dos filhos. Entrevistaram-se 10 pais de crianças surdas candidatas ao implante coclear no Hospital de Clínicas da Unicamp. Com base em uma abordagem qualitativa, procedeu-se à análise de conteúdo, sendo evidenciado que a maioria dos pais busca a cura da surdez por meio do implante coclear e, consequentemente, a aquisição da fala. Para essas famílias, o implante coclear é visto como uma solução para a surdez de seus filhos e como uma possibilidade deles terem um futuro melhor. Constatou-se que no processo de conhecimento do implante, os pais vivenciaram ansiedade e angústia frente às informações sobre os riscos e benefícios do procedimento e a necessidade de optarem pela realização ou não do implante coclear.

  16. Theoretical characterization of the BN and BP coronenes by IR, Raman, and UV-VIS spectra.

    Science.gov (United States)

    de Abreu, Leandro; López-Castillo, Alejandro

    2012-07-28

    Boron-nitrogen coronene (BNC) and boron-phosphorous coronene (BPC), not yet synthesized molecules and of possible interest for material science, are composed of six condensed rings of borazine and boraphosphabenzene molecules, respectively. They are similar to the carbon coronene molecule (CC). Moreover, CC and BNC are isoelectronic and the BPC is formally isoelectronic with respect to other coronenes, if only the valence electrons are considered. In this work, the BNC and BPC were theoretically characterized using IR, Raman, and UV-VIS spectroscopies. The coronenes studied have D(6h) and D(3h) symmetries for carbon and boron compounds, respectively. The calculated vibrational and electronic spectra for the CC are in good agreement with the experimental data, indicating that the calculations for BNC and BPC will be useful to identify these compounds, when synthesized. The main vibrational modes of the CC, BNC, and BPC are correlated. However, the BPC vibrational frequencies are substantially lower than the CC and BNC ones. The electronic ground state studies showed that the BPC has intermediate characteristics between the CC and BNC.

  17. Spectral characterization of yeast cells with an epitaxy-based UV-Vis optical sensor.

    Science.gov (United States)

    Bercu, M; Zhou, X; Lee, A C; Poenar, D P; Heng, C K; Tan, S N

    2006-06-01

    The optical spectra of yeast cells in phosphate buffer saline (PBS) were analyzed with an optical UV-vis sensor based on a shallow p(+)n junction realized in a low doped n-type epitaxial silicon layer grown on a strongly doped n(+) substrate. The presence of the n/n(+) interface allows a significantly enhanced sensitivity, due to an increased collection of carriers photogenerated both by short and large wavelengths in the range 250...800 nm. In our experiments the optical absorption of yeast cells was investigated in the wavelength range 250...500 nm as a function of the cells concentration in PBS in the range of 6 x 10(6)-2 x 10(8) cells/ml. The main absorption peaks were found at 310, 350, 400 and 427 nm, respectively. A significant red shift of the wide absorption band at 427 nm has been observed when increasing cell concentration. This red shift behaviour was nonlinear, with saturation observed for yeast concentrations larger than 5 x 10(7) cells/ml. The half-peak bandwidth of this peak also showed a most significant nonlinear variation. These findings suggest that monitoring the parameters of the absorption band at 427 nm versus cells concentration could be used, e.g. using a dedicated integrated spectrometric microsystem, for fast quantitative measurements of yeast cell concentrations in various bio-samples, with possible applications in the food industry.

  18. From pirazoloquinolines to annulated azulene dyes: UV-VIS spectroscopy and quantum chemical study

    Energy Technology Data Exchange (ETDEWEB)

    Gasiorski, P. [Faculty of Electrical Engineering, Czestochowa University of Technology, Al. Armii Krajowej 17, 42-200 Czestochowa (Poland); Danel, K.S. [Department of Chemistry, University of Agriculture, Balicka str. 122, 30-149 Krakow (Poland); Matusiewicz, M. [Faculty of Electrical Engineering, Czestochowa University of Technology, Al. Armii Krajowej 17, 42-200 Czestochowa (Poland); Uchacz, T. [Faculty of Chemistry, Jagiellonian University, Ingardena str. 3, 30-060 Krakow (Poland); Kityk, A.V., E-mail: kityk@ap.univie.ac.a [Faculty of Electrical Engineering, Czestochowa University of Technology, Al. Armii Krajowej 17, 42-200 Czestochowa (Poland)

    2010-12-15

    Paper reports UV-Vis absorption and photoluminescence spectra of 6-R derivatives (R=CH{sub 3}, O-CH{sub 3}, C(C{sub 6}H{sub 5}){sub 3}, C{sub 6}H{sub 5}-N-C{sub 10}H{sub 7}) of 4-(2-chlorophenyl)-1,3-diphenyl-1H-pyrazolo[3,4-b]quinoline, belonging to pyrazoloquinoline (PQ) family, likewise its regioisomeric products 10-R derivatives of 6-phenyl-6H-5,6,7-triazadibenzo[f,h]naphtho[3,2,1-cd]azulene representing cyclized seven-membered annulated azulene (AA) dyes. Cyclization of PQs into AAs is accompanied by a significant red shift of the first optical absorption band. This finding agrees with the results of quantum-chemical calculations performed by means of the semiempirical method PM3. As the solvent polarity rises all the dyes exhibit a blue shift of the first absorption band and a red shift of the fluorescence band. Such opposite trends in solvatochromic behavior have been reproduced within the semiempirical calculations in combination with the Lippert-Mataga dielectric polarization model. Depending on solvent polarity AA dyes emit light in the green, green-yellow or orange range of the visible spectrum what may be of interest for potential luminescent or electroluminescent applications.

  19. Capturing latent fingerprints from metallic painted surfaces using UV-VIS spectroscope

    Science.gov (United States)

    Makrushin, Andrey; Scheidat, Tobias; Vielhauer, Claus

    2015-03-01

    In digital crime scene forensics, contactless non-destructive detection and acquisition of latent fingerprints by means of optical devices such as a high-resolution digital camera, confocal microscope, or chromatic white-light sensor is the initial step prior to destructive chemical development. The applicability of an optical sensor to digitalize latent fingerprints primarily depends on reflection properties of a substrate. Metallic painted surfaces, for instance, pose a problem for conventional sensors which make use of visible light. Since metallic paint is a semi-transparent layer on top of the surface, visible light penetrates it and is reflected off of the metallic flakes randomly disposed in the paint. Fingerprint residues do not impede light beams making ridges invisible. Latent fingerprints can be revealed, however, using ultraviolet light which does not penetrate the paint. We apply a UV-VIS spectroscope that is capable of capturing images within the range from 163 to 844 nm using 2048 discrete levels. We empirically show that latent fingerprints left behind on metallic painted surfaces become clearly visible within the range from 205 to 385 nm. Our proposed streakiness score feature determining the proportion of a ridge-valley pattern in an image is applied for automatic assessment of a fingerprint's visibility and distinguishing between fingerprint and empty regions. The experiments are carried out with 100 fingerprint and 100 non-fingerprint samples.

  20. Optofluidic UV-Vis spectrophotometer for online monitoring of photocatalytic reactions.

    Science.gov (United States)

    Wang, Ning; Tan, Furui; Zhao, Yu; Tsoi, Chi Chung; Fan, Xudong; Yu, Weixing; Zhang, Xuming

    2016-06-29

    On-chip integration of optical detection units into the microfluidic systems for online monitoring is highly desirable for many applications and is also well in line with the spirit of optofluidics technology-fusion of optics and microfluidics for advanced functionalities. This paper reports the construction of a UV-Vis spectrophotometer on a microreactor, and demonstrates the online monitoring of the photocatalytic degradations of methylene blue and methyl orange under different flow rates and different pH values by detecting the intensity change and/or the peak shift. The integrated device consists of a TiO2-coated glass substrate, a PDMS micro-sized reaction chamber and two flow cells. By comparing with the results of commercial equipment, we have found that the measuring range and the sensitivity are acceptable, especially when the transmittance is in the range of 0.01-0.9. This integrated optofluidic device can significantly cut down the test time and the sample volume, and would provide a versatile platform for real-time characterization of photochemical performance. Moreover, its online monitoring capability may enable to access the usually hidden information in biochemical reactions like intermediate products, time-dependent processes and reaction kinetics.

  1. A new method for the absolute radiance calibration for UV-vis measurements of scattered sunlight

    Science.gov (United States)

    Wagner, T.; Beirle, S.; Dörner, S.; Penning de Vries, M.; Remmers, J.; Rozanov, A.; Shaiganfar, R.

    2015-10-01

    Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds, and the shortwave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV-vis instruments that measure the spectrally resolved sky radiance, for example zenith sky differential optical absorption spectroscopy (DOAS) instruments or multi-axis (MAX)-DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method, clear-sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about ozone column density during the measurements be constant and known.

  2. Electrochemical and UV-Vis/ESR spectroelectrochemical properties of thienylenevinylenes substituted by a 4-cyanostyryl group

    Energy Technology Data Exchange (ETDEWEB)

    Czichy, M., E-mail: Malgorzata.Czichy@polsl.p [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Stolarczyk, A. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Wagner, P. [Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Domagala, W. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Lapkowski, M. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Sklodowska-Curie Str., 41-819 Zabrze (Poland); Officer, D.L. [Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia)

    2011-04-30

    Highlights: {yields} Electropolymerisation of the cyanostyryl substituted thienylenevinylene derivative affords a polymer having an optical band gap of ca. 1.8 eV, supplemented by soluble oligomers. {yields} Vinyl bonds of the thienylenevinylene derivative were found unstable upon electrooxidation of the molecule to a radical cation. {yields} Two groups of spins of the radical cation of the thienylenevinylene derivative have been identified. - Abstract: The {pi}-electron delocalisation in conjugated thienylenevinylenes bearing arylethenyl chromophores, makes those materials interesting candidates for electro-optic applications. In this study, we report the results of electrochemical and UV-Vis/ESR spectroelectrochemical studies of a pair of thienylenevinylenes substituted by the 4-cyanostyryl group, bearing either a hydrogen, or methyl group terminated {alpha} carbons at the peripheral thiophene rings. The reactivity of various functional segments of investigated molecules was assessed by comparing the reactivity of the protected and unprotected counterparts and the behaviour of their electrooxidation products. For the capped derivative, two irreversible anodic redox processes giving electrochemically inactive products were observed, while the uncapped molecule yields electroactive materials already upon its first oxidation step.

  3. The identification of chromophores in ancient glass by the use of UV-VIS-NIR spectroscopy

    Science.gov (United States)

    Meulebroeck, W.; Baert, K.; Wouters, H.; Cosyns, P.; Ceglia, A.; Cagno, S.; Janssens, K.; Nys, K.; Terryn, H.; Thienpont, H.

    2010-04-01

    In this publication optical spectroscopy is considered to be a supplementary technique to study ancient colored glass. It results from a systematic study of the UV-VIS-NIR transmission spectra of intentionally colored glass fragments from various archaeological and historical sites and dated from the Roman period to the 21th century AD. The main goal consists of defining optical sensing parameters for this type of material. The considered colorants are iron, cobalt, manganese, copper and chromium. It is proved that many cases exist where optical spectroscopy can be seen as a straightforward, non-destructive, low-cost and in-situ applicable technique in identifying authentic material or to obtain information about the origin of the material. Possible sensing parameters are defined as the absence/presence of absorption bands characteristic for a specific coloring metal oxide and the spectral position of these bands. These parameters could reveal information about the applied furnace conditions and/or to the composition of the glass matrix. It is shown that the cobalt absorption band situated around 535 nm for soda rich glasses (Roman and industrial times) is shifted towards 526 nm for potash rich glasses (medieval and post-medieval times).

  4. Mathematical calculations of iron complex stoichiometry by direct UV-Vis spectrophotometry.

    Science.gov (United States)

    Filipský, Tomáš; Říha, Michal; Hrdina, Radomír; Vávrová, Kateřina; Mladěnka, Přemysl

    2013-08-01

    The effects of iron-chelating agents on miscellaneous pathologies are currently largely tested. Due to various indications, different properties for chelators are required. A stoichiometry of the complex in relation to pH is one of the crucial factors. Moreover, the published data on the stoichiometry, especially concerning flavonoids, are equivocal. In this study, a new complementary approach was employed for the determination of stoichiometry in 10 iron-chelating agents, including clinically used drugs, by UV-Vis spectrophotometry at relevant pH conditions and compared with the standard Job's method. This study showed that the simple approach based on absorbance at the wavelength of complex absorption maximum was sufficient when the difference between absorption maximum of substance and complex was high. However, in majority of substances this difference was much lower (9-73 nm). The novel complementary approach was able to determine the stoichiometry in all tested cases. The major benefit of this method compared to the standard Job's approach seems to be its capability to reveal a reaction stoichiometry in chelators with moderate affinity to iron. In conclusion, using this complementary method may explain several previous contradictory data and lead to a better understanding of the underlying mechanisms of chelator's action. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. A Morte Cansada na visão do cineasta Fritz Lang

    Directory of Open Access Journals (Sweden)

    Luciana Helena Mussi

    2015-02-01

    Full Text Available Este trabalho estuda a finitude no contexto do envelhecimento por meio do filme A Morte Cansada do cineasta Fritz Lang. Discute a visão do cineasta, especialmente a existência humana, tendo como eixo condutor uma reflexão sobre envelhecimento e morte, questões intrinsecamente ligadas ao tema do sentido da vida, remetendo às discussões sobre a imortalidade da alma e a existência de Deus. Neste filme Lang apresenta a história das três luzes: tentativas de esperança, conflitos sobre o amor, a conquista da vida e a aceitação da morte. A investigação realizada mostra que a arte que se faz através do cinema contribui na compreensão do caráter finito da vida, uma questão complexa na velhice, a constante busca de respostas para as inquietudes do que seja o morrer, o que representa para o velho ser definitivamente um ser finito.  

  6. FTIR and UV-Vis Spectroscopic Studies of Black Soap Film.

    Science.gov (United States)

    Du; Lu; Liang

    1998-11-01

    FTIR and UV-vis spectroscopies have been employed to investigate the self-assembly features of a black soap film (BSF) prepared from aqueous solution consisting of 10(-2) M cetyltrimethylammonium bromide (CTAB) and 10(-3) M thiazole yellow (TY) in the liquid-crystalline and gel states, respectively. The construction of two surfactant monolayers of the soap film is independent of the thickness of aqueous core, and the thickness is approximately 1.7 nm at equilibrium. In the liquid-crystalline state, the methylene segments of the hydrocarbon chains are averagely oriented at an angle of 70 degrees with respect to the film normal, and the alkyl chains take a long-range interaction to improve the film elasticity. The TY molecules in the film are horizontally aligned at the monolayer interface in the J-aggregate form. The double-negatively charged TY aggregate greatly enhances the film stability. Dye neutral red is further introduced into the CTAB soap film, the film lifetime is related to the type of the added dyes, in the order of cationic < nonionic < anionic. Copyright 1998 Academic Press.

  7. Theoretical characterization of the BN and BP coronenes by IR, Raman, and UV-VIS spectra

    Science.gov (United States)

    de Abreu, Leandro; López-Castillo, Alejandro

    2012-07-01

    Boron-nitrogen coronene (BNC) and boron-phosphorous coronene (BPC), not yet synthesized molecules and of possible interest for material science, are composed of six condensed rings of borazine and boraphosphabenzene molecules, respectively. They are similar to the carbon coronene molecule (CC). Moreover, CC and BNC are isoelectronic and the BPC is formally isoelectronic with respect to other coronenes, if only the valence electrons are considered. In this work, the BNC and BPC were theoretically characterized using IR, Raman, and UV-VIS spectroscopies. The coronenes studied have D6h and D3h symmetries for carbon and boron compounds, respectively. The calculated vibrational and electronic spectra for the CC are in good agreement with the experimental data, indicating that the calculations for BNC and BPC will be useful to identify these compounds, when synthesized. The main vibrational modes of the CC, BNC, and BPC are correlated. However, the BPC vibrational frequencies are substantially lower than the CC and BNC ones. The electronic ground state studies showed that the BPC has intermediate characteristics between the CC and BNC.

  8. A visão de escolares sobre drogas no uso de um jogo educativo

    Directory of Open Access Journals (Sweden)

    Sandra Rebello

    Full Text Available Este estudo enfatiza a relevância da mediação cultural no uso de tecnologias educacionais. Para tal, descreve a percepção de 62 escolares da rede pública do Rio de Janeiro sobre temas abordados no Jogo da Onda, um jogo sobre o uso de drogas, e o interesse do grupo pelo material. A partir de grupos focais, observação das partidas e questionários, foi observado que a iniciação ao uso de drogas está relacionada à: pressão social de grupo, fácil acesso às drogas e ao não reconhecimento de que o consumo pessoal, mesmo descontínuo, pode levar à dependência química. Dissonâncias entre a visão dos escolares e o discurso preventivo repressivo e/ou técnico informativo sugere que as ações educativas devem privilegiar formas de apreensão das informações transmitidas, focando a interatividade, a interlocução, a informação e a reflexão.

  9. A visão de escolares sobre drogas no uso de um jogo educativo

    Directory of Open Access Journals (Sweden)

    Sandra Rebello

    2001-02-01

    Full Text Available Este estudo enfatiza a relevância da mediação cultural no uso de tecnologias educacionais. Para tal, descreve a percepção de 62 escolares da rede pública do Rio de Janeiro sobre temas abordados no Jogo da Onda, um jogo sobre o uso de drogas, e o interesse do grupo pelo material. A partir de grupos focais, observação das partidas e questionários, foi observado que a iniciação ao uso de drogas está relacionada à: pressão social de grupo, fácil acesso às drogas e ao não reconhecimento de que o consumo pessoal, mesmo descontínuo, pode levar à dependência química. Dissonâncias entre a visão dos escolares e o discurso preventivo repressivo e/ou técnico informativo sugere que as ações educativas devem privilegiar formas de apreensão das informações transmitidas, focando a interatividade, a interlocução, a informação e a reflexão.

  10. Combined UV/vis and micro-tomography investigation of acetaminophen dissolution from granules.

    Science.gov (United States)

    Kašpar, Ondřej; Tokárová, Viola; Oka, Sarang; Sowrirajan, Koushik; Ramachandran, Rohit; Štěpánek, František

    2013-12-31

    The X-ray micro-tomography (micro-CT) technique has been used to visualize the microstructure of granules produced by high shear wet granulation and the dynamic evolution of porosity during granule dissolution. Using acetaminophen (paracetamol) as the active pharmaceutical ingredient (API) and microcrystalline cellulose (Avicel PH-200) as an excipient, the porosity of the granules was systematically influenced by the granulation process parameters (binder/solids ratio, impeller speed and wet massing time). An increase of granule porosity from 7% to 10% and 18% lead to a decrease of the dissolution time t90 from 435 min to 98 min and 37 min, respectively. The combination of time-resolved micro-CT imaging with UV/vis detection of the quantity dissolved made it possible to evaluate the effective diffusion coefficient of the API through the granule structure, and thus establish a quantitative structure–property relationship for dissolution. A power-law dependence of the effective diffusivity on porosity (Archie's law) was found to hold.

  11. New insight in the template decomposition process of large zeolite ZSM-5 crystals: an in situ UV-Vis/fluorescence micro-spectroscopy study

    NARCIS (Netherlands)

    Karwacki, L.; Weckhuysen, B.M.

    2011-01-01

    A combination of in situ UV-Vis and confocal fluorescence micro-spectroscopy was used to study the template decomposition process in large zeolite ZSM-5 crystals. Correlation of polarized light dependent UV-Vis absorption spectra with confocal fluorescence emission spectra in the 400–750 nm region

  12. Evaluation de l’opinion des étudiants de l’enseignement secondaire et supérieur de Bruxelles vis-à-vis des concepts d’évolution (humaine)

    OpenAIRE

    Perbal, Laurence; Slachmuylder, Jean-Louis; Susanne, Charles

    2006-01-01

    Le refus de la théorie de l’évolution semble principalement motivé par des raisons religieuses et les attaques anti-darwiniennes se multiplient en Europe. Nous avons donc entrepris d’évaluer l’opinion des étudiants bruxellois vis-à-vis du concept d’évolution et des théories darwinienne et néodarwinienne de l’évolution. Afin d’atteindre cet objectif, nous avons procédé à une enquête par questionnaire à choix multiples. Au sein de l’échantillon total (1163 individus), près d’un quart des répond...

  13. visCOS: An R-package to evaluate model performance of hydrological models

    Science.gov (United States)

    Klotz, Daniel; Herrnegger, Mathew; Wesemann, Johannes; Schulz, Karsten

    2016-04-01

    The evaluation of model performance is a central part of (hydrological) modelling. Much attention has been given to the development of evaluation criteria and diagnostic frameworks. (Klemeš, 1986; Gupta et al., 2008; among many others). Nevertheless, many applications exist for which objective functions do not yet provide satisfying summaries. Thus, the necessity to visualize results arises in order to explore a wider range of model capacities, be it strengths or deficiencies. Visualizations are usually devised for specific projects and these efforts are often not distributed to a broader community (e.g. via open source software packages). Hence, the opportunity to explicitly discuss a state-of-the-art presentation technique is often missed. We therefore present a comprehensive R-package for evaluating model performance by visualizing and exploring different aspects of hydrological time-series. The presented package comprises a set of useful plots and visualization methods, which complement existing packages, such as hydroGOF (Zambrano-Bigiarini et al., 2012). It is derived from practical applications of the hydrological models COSERO and COSEROreg (Kling et al., 2014). visCOS, providing an interface in R, represents an easy-to-use software package for visualizing and assessing model performance and can be implemented in the process of model calibration or model development. The package provides functions to load hydrological data into R, clean the data, process, visualize, explore and finally save the results in a consistent way. Together with an interactive zoom function of the time series, an online calculation of the objective functions for variable time-windows is included. Common hydrological objective functions, such as the Nash-Sutcliffe Efficiency and the Kling-Gupta Efficiency, can also be evaluated and visualized in different ways for defined sub-periods like hydrological years or seasonal sections. Many hydrologists use long-term water-balances as a

  14. Software design for the VIS instrument onboard the Euclid mission: a multilayer approach

    Science.gov (United States)

    Galli, E.; Di Giorgio, A. M.; Pezzuto, S.; Liu, S. J.; Giusi, G.; Li Causi, G.; Farina, M.; Cropper, M.; Denniston, J.; Niemi, S.

    2014-07-01

    The Euclid mission scientific payload is composed of two instruments: a VISible Imaging Instrument (VIS) and a Near Infrared Spectrometer and Photometer instrument (NISP). Each instrument has its own control unit. The Instrument Command and Data Processing Unit (VI-CDPU) is the control unit of the VIS instrument. The VI-CDPU is connected directly to the spacecraft by means of a MIL-STD-1553B bus and to the satellite Mass Memory Unit via a SpaceWire link. All the internal interfaces are implemented via SpaceWire links and include 12 high speed lines for the data provided by the 36 focal plane CCDs readout electronics (ROEs) and one link to the Power and Mechanisms Control Unit (VI-PMCU). VI-CDPU is in charge of distributing commands to the instrument sub-systems, collecting their housekeeping parameters and monitoring their health status. Moreover, the unit has the task of acquiring, reordering, compressing and transferring the science data to the satellite Mass Memory. This last feature is probably the most challenging one for the VI-CDPU, since stringent constraints about the minimum lossless compression ratio, the maximum time for the compression execution and the maximum power consumption have to be satisfied. Therefore, an accurate performance analysis at hardware layer is necessary, which could delay too much the design and development of software. In order to mitigate this risk, in the multilayered design of software we decided to design a middleware layer that provides a set of APIs with the aim of hiding the implementation of the HW connected layer to the application one. The middleware is built on top of the Operating System layer (which includes the Real-Time OS that will be adopted) and the onboard Computer Hardware. The middleware itself has a multi-layer architecture composed of 4 layers: the Abstract RTOS Adapter Layer (AOSAL), the Speci_c RTOS Adapter Layer (SOSAL), the Common Patterns Layer (CPL), the Service Layer composed of two subgroups which

  15. Penggunaan Vis-NIR untuk Deteksi Serangan Huanglongbing pada Daun Jeruk

    Directory of Open Access Journals (Sweden)

    Raden Arief Firmansyah

    2017-04-01

    Full Text Available Abstract Huanglongbing is citrus disease which is a major threat for citrus orchard. Neither disease has a cure nor an efficient means of control. Early detection is important to prevent development and spread of the disease. The most effective detection used DNA test by PCR. However, identification used DNA test required sample preparation, time-consuming and expensive. The objective of this study was to build detection of healthy and HLB-infected leaves software. The leaf samples collected from citrus orchard in Situgede village, Bogor. Sample leaves divided into three group, Huanglongbing-infected leaves, healthy leaves and asymptomatic leaves. All samples was tested by PCR for verification visual symptoms of huanglongbing. Vis-NIR spectrometer with a spectra range of 339 to 1022nm was used to acquisition HLB-infected and healthy leaves spectral data. MSC, SNV, baseline correction, first and second derivative were used for pretreatment method. Artificial neural network was used to build classification model. X-loading plot from principal component analysis was used to obtain sensitive wavelength. Classification for healthy and HLB-infected classs used sensitive wavelength baseline correction-based had the best performance and high accuracy (100%. The classification model was embedded in software PC-desktop based which was used visual basic programming language. Asymptomatic leaves spectral from HLB-positive tree were used to testing classification model. Model classified data into HLB-infected group, which was consistent with PCR test. The result from this study indicated that developed software could be used to HLB detection in early stage of disease. Abstrak Huanglongbing adalah penyakit jeruk yang merupakan ancaman utama bagi budidaya jeruk. Tidak ada pengendalian yang tepat untuk Huanglongbing. Deteksi dini penting untuk mencegah penyebaran dan pengembangan penyakit ini. Deteksi dini yang paling efektif menggunakan tes DNA dengan PCR

  16. UV-vis in situ spectrometry data mining through linear and non linear analysis methods

    Directory of Open Access Journals (Sweden)

    Liliana López-Kleine

    2014-01-01

    Full Text Available Los espectrómetros UV-visibles son captores que registran la absorbancia de luz emitida por partículas suspendidas en el agua a diferentes longitudes de onda y proporcionan mediciones en continuo, las cuales pueden ser interpretadas como concentraciones de parámetros comúnmente usados para evaluar el estado físico-químico de cuerpos de agua. Parámetros clásicos usados para detectar la presencia de contaminación en el agua son los sólidos suspendidos totales (TSS y la demanda química de oxígeno (CDO. Métodos de análisis flexibles y eficientes son necesarios para extraer información útil para fines de gestión y monitoreo a partir de los datos multivariados que proporcionan los captores. Se han usado métodos de calibración de tipo regresión parcial por mínimos cuadrados parciales (PLS. Varios autores han demostrado la necesidad de realizar la calibración para cada tipo de datos y cada cuerpo de agua, así como explorar métodos de análisis lineales y no lineales para el análisis de datos UV-visible y para determinar su relación con parámetros clásicos. En este trabajo se aplican métodos de análisis multivariado lineales y no lineales para la minería de datos UV-vis de alta dimensión, los cuales resultan útiles para la identificación de relaciones entre parámetros y longitudes de onda, la detección de muestras atípicas, así como la detección de estructuras no lineales en los datos.

  17. Contrasting UV-Vis Spectra of Terrestrial and Algal Derived Dissolved Organic Matter.

    Science.gov (United States)

    Adams, Jessica; Tipping, Edward; Scholefield, Paul; Feuchtmayr, Heidrun; Carter, Heather; Keenan, Patrick

    2016-04-01

    Dissolved organic matter (DOM) is an important freshwater component. It controls aquatic ecological and biochemical cycling, and can be problematic in industrial water treatment. Thus, the demand for effective and reliable monitoring is growing. The heterogeneity of the spectroscopic properties of DOM are such that measurements of absorbance at a single wavelength cannot provide accurate predictions of [DOC]. Previous construction of a two-component model, based on the combination of absorbance at two wavelengths and a constant accountable for non-absorbing DOM, resulted in good predictions of [DOC] across approximately 1800 different freshwater systems (R2=0.99). However, there were isolated cases where the model appreciably underestimated [DOC], including shallow lakes and reservoirs in the Yangtze basin, China where waters were deemed to be highly eutrophic. Here, we used a revised series of samples, from small scale algal dominated microcosms, mesocosms and catchment scale field samples to explore the capability of the two component model in situations where algae may be the dominant producer of aquatic DOC. Absorbances were measured using a laboratory based UV-Vis spectrometer and subsamples were also analysed through combustion and infra-red detection. In both the microcosms and mesocosms, the model failed to provide a reliable fit, and [DOC] was considerably underestimated. At the field scale, analysis of 55 samples from a combination of reservoirs, arable ponds, streams and rivers produced mostly reliable predictions of [DOC] (R2=0.96), which can be attributed to the dominant input of terrestrial DOM. Samples of shallow, enclosed meres from the North-West of the UK showed hints of similar behaviour to that of the Chinese lakes, suggesting some influences from algal DOM. Our results therefore provide evidence that algae may produce complex forms of DOM that harbour different spectroscopic properties to terrestrially derived material, in the UV spectral range.

  18. A Visão Baseada em Recursos da Inteligência Competitiva

    Directory of Open Access Journals (Sweden)

    Paulo Henrique de Oliveira

    2013-04-01

    Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2013v15n35p141   Neste artigo analisa-se a importância da Inteligência Competitiva (IC como uma capacidade estratégica para as organizações contemporâneas, especialmente para àquelas instaladas em ambientes caracterizados por uma intensa e dinâmica competição. A discussão acontece no contexto da Visão Baseada em Recursos (Resource-Based View, no inglês, uma das mais importantes correntes teóricas do campo da estratégica que busca explicar o fenômeno da vantagem competitiva a partir do controle de recursos e capacidades diferenciados pelas organizações. Como suposição inicial, acredita-se que o valor estratégico da IC está concentrado, principalmente, no conhecimento tácito dos seus profissionais e nos relacionamentos construídos ao longo do tempo (path dependence com seus pares e tomadores de decisões estratégicas de suas respectivas organizações, uma vez que os mesmos não podem ser imitados ou desenvolvidos rapidamente pelos concorrentes, conforme sugerem os estudos de autores como Wernerfelt (1984, Nonaka e Takeuchi (1995, Barney (1986a, 1991, 2001, Dierickx e Cool (1989, Mahoney e Pandian (1992, Amit e Schoemaker (1993 e Grant (1991, 1996.

  19. Responsividade do serviço de enfermagem na visão do cliente

    Directory of Open Access Journals (Sweden)

    Ana Vanessa Deffaccio Rodrigues

    Full Text Available A expectativa criada pelo indivíduo na hospitalização e a percepção que ele tem do cuidado que recebe quando hospitalizado são aspectos que definem seu grau de satisfação. Assim, surgiu o conceito responsividade no campo da avaliação em saúde. O objetivo deste estudo é mensurar a responsividade do serviço de enfermagem de uma unidade médico-cirúrgica de um hospital universitário público, na visão do cliente, por meio de um instrumento que aborda duas categorias: Expectativas e Percepções. Trata-se de pesquisa quantitativa que utilizou entrevistas. Para análise dos dados realizou-se o cálculo da taxa de satisfação relativa e do intervalo, o que possibilitou a classificação do serviço de enfermagem. Correlacionam-se as características socioeconômicas com as experiências prévias de internação dos entrevistados. Os resultados demonstraram que o serviço de enfermagem está com uma representação Adequada. Alguns fatores foram considerados responsáveis pelo fenômeno da alta satisfação, como viés de gratidão e de aquiescência.

  20. Responsividade do serviço de enfermagem na visão do cliente

    Directory of Open Access Journals (Sweden)

    Ana Vanessa Deffaccio Rodrigues

    2012-12-01

    Full Text Available A expectativa criada pelo indivíduo na hospitalização e a percepção que ele tem do cuidado que recebe quando hospitalizado são aspectos que definem seu grau de satisfação. Assim, surgiu o conceito responsividade no campo da avaliação em saúde. O objetivo deste estudo é mensurar a responsividade do serviço de enfermagem de uma unidade médico-cirúrgica de um hospital universitário público, na visão do cliente, por meio de um instrumento que aborda duas categorias: Expectativas e Percepções. Trata-se de pesquisa quantitativa que utilizou entrevistas. Para análise dos dados realizou-se o cálculo da taxa de satisfação relativa e do intervalo, o que possibilitou a classificação do serviço de enfermagem. Correlacionam-se as características socioeconômicas com as experiências prévias de internação dos entrevistados. Os resultados demonstraram que o serviço de enfermagem está com uma representação Adequada. Alguns fatores foram considerados responsáveis pelo fenômeno da alta satisfação, como viés de gratidão e de aquiescência.

  1. UV-Vis spectroscopy and solvatochromism of the tyrosine kinase inhibitor AG-1478.

    Science.gov (United States)

    Khattab, Muhammad; Wang, Feng; Clayton, Andrew H A

    2016-07-05

    The effect of twenty-one solvents on the UV-Vis spectrum of the tyrosine kinase inhibitor AG-1478 was investigated. The absorption spectrum in the range 300-360nm consisted of two partially overlapping bands at approximately 340nm and 330nm. The higher energy absorption band was more sensitive to solvent and exhibited a peak position that varied from 327nm to 336nm, while the lower energy absorption band demonstrated a change in peak position from 340nm to 346nm in non-chlorinated solvents. The fluorescence spectrum of AG-1478 was particularly sensitive to solvent. The wavelength of peak intensity varied from 409nm to 495nm with the corresponding Stokes shift in the range of 64nm to 155nm (4536cm(-1) to 9210cm(-1)). We used a number of methods to assess the relationship between spectroscopic properties and solvent properties. The detailed analysis revealed that for aprotic solvents, the peak position of the emission spectrum in wavenumber scale correlated with the polarity (dielectric constant or ET(30)) of the solvent. In protic solvents, a better correlation was observed between the hydrogen bonding power of the solvent and the position of the emission spectrum. Moreover, the fluorescence quantum yields were larger in aprotic solvents as compared to protic solvents. This analysis underscores the importance of polarity and hydrogen-bonding environment on the spectroscopic properties of AG-1478. These studies will assume relevance in understanding the interaction of AG-1478 in vitro and in vivo. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Experimental conditions affecting the kinetics of aqueous HCN polymerization as revealed by UV-vis spectroscopy.

    Science.gov (United States)

    Marín-Yaseli, Margarita R; Moreno, Miguel; de la Fuente, José L; Briones, Carlos; Ruiz-Bermejo, Marta

    2017-10-12

    HCN polymerization is one of the most important and fascinating reactions in prebiotic chemistry, and interest in HCN polymers in the field of materials science is growing. However, little is known about the kinetics of the HCN polymerization process. In the present study, a first approach to the kinetics of two sets of aqueous HCN polymerizations, from NH4CN and NaCN, at middle temperatures between 4 and 38°C, has been carried out. For each series, the presence of air and salts in the reaction medium has been systematically explored. A previous kinetic analysis was conducted during the conversion of the insoluble black HCN polymers obtained as gel fractions in these precipitation polymerizations for a reaction of one month, where a limit conversion was achieved at the highest polymerization temperature. The kinetic description of the gravimetric data for this complex system shows a clear change in the linear dependence with the polymerization temperature for the reaction from NH4CN, besides a relevant catalytic effect of ammonium, in comparison with those data obtained from the NaCN series. These results also demonstrated the notable influence of air, oxygen, and the saline medium in HCN polymer formation. Similar conclusions were reached when the sol fractions were monitored by UV-vis spectroscopy, and a Hill type correlation was used to describe the polymerization profiles obtained. This technique was chosen because it provides an easy, prompt and fast method to follow the evolution of the liquid or continuous phase of the process under study. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Chromatic correction for a VIS-SWIR zoom lens using optical glasses

    Science.gov (United States)

    Zhao, Yang; Williams, Daniel J. L.; McCarthy, Peter; Visconti, Anthony J.; Bentley, Julie L.; Moore, Duncan T.

    2015-09-01

    With the advancement in sensors, hyperspectral imaging in short wave infrared (SWIR 0.9 μm to 1.7 μm) now has wide applications, including night vision, haze-penetrating imaging, etc. Most conventional optical glasses can be material candidates for designing in the SWIR as they transmit up to 2.2 μm. However, since SWIR is in the middle of the glasses' major absorption wavebands in UV and IR, the flint glasses in SWIR are less dispersive than in the visible spectrum. As a result, the glass map in the SWIR is highly compressed, with crowns and flints all clustering together. Thus correcting for chromatic aberration is more challenging in the SWIR, since the Abbé number ratio of the same glass combination is reduced. Conventionally, fluorides, such as CaF2 and BaF2, are widely used in designing SWIR system due to their unique dispersion properties, even though they are notorious for poor manufacturability or even high toxicity. For lens elements in a zoom system, the ray bundle samples different sections of the each lens aperture as the lens zooms. This creates extra uncertainty in correcting chromatic aberrations. This paper focuses on using only commercially available optical glasses to color-correct a 3X dual-band zoom lens system in the VIS-SWIR. The design tools and techniques are detailed in terms of material selections to minimize the chromatic aberrations in such a large spectrum band and all zoom positions. Examples are discussed for designs with different aperture stop locations, which considerably affect the material choices.

  4. A portable device for detecting fruit quality by diffuse reflectance Vis/NIR spectroscopy

    Science.gov (United States)

    Sun, Hongwei; Peng, Yankun; Li, Peng; Wang, Wenxiu

    2017-05-01

    Soluble solid content (SSC) is a major quality parameter to fruit, which has influence on its flavor or texture. Some researches on the on-line non-invasion detection of fruit quality were published. However, consumers desire portable devices currently. This study aimed to develop a portable device for accurate, real-time and nondestructive determination of quality factors of fruit based on diffuse reflectance Vis/NIR spectroscopy (520-950 nm). The hardware of the device consisted of four units: light source unit, spectral acquisition unit, central processing unit, display unit. Halogen lamp was chosen as light source. When working, its hand-held probe was in contact with the surface of fruit samples thus forming dark environment to shield the interferential light outside. Diffuse reflectance light was collected and measured by spectrometer (USB4000). ARM (Advanced RISC Machines), as central processing unit, controlled all parts in device and analyzed spectral data. Liquid Crystal Display (LCD) touch screen was used to interface with users. To validate its reliability and stability, 63 apples were tested in experiment, 47 of which were chosen as calibration set, while others as prediction set. Their SSC reference values were measured by refractometer. At the same time, samples' spectral data acquired by portable device were processed by standard normalized variables (SNV) and Savitzky-Golay filter (S-G) to eliminate the spectra noise. Then partial least squares regression (PLSR) was applied to build prediction models, and the best predictions results was achieved with correlation coefficient (r) of 0.855 and standard error of 0.6033° Brix. The results demonstrated that this device was feasible to quantitatively analyze soluble solid content of apple.

  5. [UV-Vis spectrum characteristics of phycocyanin in water from Taihu lake].

    Science.gov (United States)

    Zhang, Jing; Wei, Yu-Chun; Wang, Guo-Xiang; Cheng, Chun-Mei; Xia, Xiao-Rui

    2014-05-01

    The present paper analyzed the UV-Vis spectrum characteristics of phycocyanin extracted from 75 water samples around Meiliang Bay of Taihu Lake, China in spring, summer and autumn, 2011, taking standard sample of phycocyanin, Micro-cystic aeruginosa and Anabaena cultured indoor as the reference, and discussed the difference and relation of spectrum among water samples, standard sample and single algae samples. According to the number of absorption peak in the wavelength range from 500 to 700 nm, phycocyanin spectrum of water sampling in Taihu Lake can be divided into three patterns: no peak, single peak and two peaks. In the first pattern, the absorbance changed smoothly and no absorption peak was observed around 620 nm. Depending on the absorption difference in the wavelength range from 300 to 450 nm, this pattern can be divided into type I and type II. Type I only had a absorption peak near 260 nm, with the similar spectrum of chromophoric dissolved organic matter (CDOM) in the wavelength range from 250 to 800 nm. Type II had absorption peak respectively near 260 and 330 nm. In single peak pattern and two peaks pattern, significant absorption peak of phycocyanin appeared around 620 nm. Compared to the other patterns, single peak pattern was more similar to that of standard sample and single algae samples, but different in their maximum absorption peaks position and relative absorption intensity in the wavelength range of 250 approximately 300, 300 approximately 450 and 500 approximately 700 nm, because of different algae species and purity after extraction. In the two peaks pattern, another absorption peak appeared at 670nm, with the absorption shoulder from 350 to 450 nm, and shared the absorption characteristics of phycocyanin and chlorophyll complex protein. The research can provide a basic support for the phycocyanin quantitation and blooms monitoring in Taihu Lake.

  6. Online in-tube microextractor coupled with UV-Vis spectrophotometer for bisphenol A detection.

    Science.gov (United States)

    Poorahong, Sujittra; Thammakhet, Chongdee; Thavarungkul, Panote; Kanatharana, Proespichaya

    2013-01-01

    A simple and high extraction efficiency online in-tube microextractor (ITME) was developed for bisphenol A (BPA) detection in water samples. The ITME was fabricated by a stepwise electrodeposition of polyaniline, polyethylene glycol and polydimethylsiloxane composite (CPANI) inside a silico-steel tube. The obtained ITME coupled with UV-Vis detection at 278 nm was investigated. By this method, the extraction and pre-concentration of BPA in water were carried out in a single step. Under optimum conditions, the system provided a linear dynamic range of 0.1 to 100 μM with a limit of detection of 20 nM (S/N ≥3). A single in-tube microextractor had a good stability of more than 60 consecutive injections for 10.0 μM BPA with a relative standard deviation of less than 4%. Moreover, a good tube-to-tube reproducibility and precision were obtained. The system was applied to detect BPA in water samples from six brands of baby bottles and the results showed good agreement with those obtained from the conventional GC-MS method. Acceptable percentage recoveries from the spiked water samples were obtained, ranging from 83-102% for this new method compared with 73-107% for the GC-MS standard method. This new in-tube CPANI microextractor provided an excellent extraction efficiency and a good reproducibility. In addition, it can also be easily applied for the analysis of other polar organic compounds contaminated in water sample.

  7. Mau desempenho escolar: uma visão atual Poor school performance: an updated review

    Directory of Open Access Journals (Sweden)

    Cláudia Machado Siqueira

    2011-02-01

    Full Text Available Este estudo tem como objetivo uma revisão atualizada sobre o tema de mau desempenho escolar para profissionais da área de saúde e educação. Aborda aspectos atuais da educação, de aprendizagem e das principais condições envolvidas em mau desempenho escolar. Apresenta dados atualizados sobre os principais aspectos da neurobiologia, epidemiologia, etiologia, quadro clínico, comorbidades, diagnóstico, intervenção precoce e tratamento das principais patologias envolvidas. Trata-se de uma revisão abrangente, não sistemática da literatura sobre aprendizagem, desempenho escolar, transtorno de aprendizagem (dislexia, discalculia e disgrafia, transtorno de déficit de atenção/hiperatividade (TDA/H e transtorno de desenvolvimento de coordenação (TDC. O mau desempenho escolar é um sintoma frequente em nossas crianças com graves repercussões emocionais, sociais e econômicas. Uma visão atualizada do tema facilita o raciocínio clínico, o diagnóstico correto e o tratamento adequado.This study aims to develop a comprehensive review on the issue of poor school performance for professionals in both health and education areas. It discusses current aspects of education, learning and the main conditions involved in underachievement. It also presents updated data on key aspects of neurobiology, epidemiology, etiology, clinical presentation, comorbidities and diagnosis, early intervention and treatment of the major pathologies comprised. It is a comprehensive, non-systematic literature review on learning, school performance, learning disorders (dyslexia, dyscalculia and dysgraphia, attention deficit / hyperactivity disorder (ADHD and developmental coordination disorder (DCD. Poor school performance is a frequent problem faced by our children, causing serious emotional, social and economic issues. An updated view of the subject facilitates clinical reasoning, accurate diagnosis and appropriate treatment.

  8. Experimental conditions affecting the kinetics of aqueous HCN polymerization as revealed by UV-vis spectroscopy

    Science.gov (United States)

    Marín-Yaseli, Margarita R.; Moreno, Miguel; de la Fuente, José L.; Briones, Carlos; Ruiz-Bermejo, Marta

    2018-02-01

    HCN polymerization is one of the most important and fascinating reactions in prebiotic chemistry, and interest in HCN polymers in the field of materials science is growing. However, little is known about the kinetics of the HCN polymerization process. In the present study, a first approach to the kinetics of two sets of aqueous HCN polymerizations, from NH4CN and NaCN, at middle temperatures between 4 and 38 °C, has been carried out. For each series, the presence of air and salts in the reaction medium has been systematically explored. A previous kinetic analysis was conducted during the conversion of the insoluble black HCN polymers obtained as gel fractions in these precipitation polymerizations for a reaction of one month, where a limit conversion was achieved at the highest polymerization temperature. The kinetic description of the gravimetric data for this complex system shows a clear change in the linear dependence with the polymerization temperature for the reaction from NH4CN, besides a relevant catalytic effect of ammonium, in comparison with those data obtained from the NaCN series. These results also demonstrated the notable influence of air, oxygen, and the saline medium in HCN polymer formation. Similar conclusions were reached when the sol fractions were monitored by UV-vis spectroscopy, and a Hill type correlation was used to describe the polymerization profiles obtained. This technique was chosen because it provides an easy, prompt and fast method to follow the evolution of the liquid or continuous phase of the process under study.

  9. Note: Enhanced production of He⁺ from the Versatile Ion Source (VIS) in off-resonance configuration.

    Science.gov (United States)

    Castro, G; Mascali, D; Celona, L; Gammino, S; Caliri, C; Di Bartolo, F; Lanaia, D; Mazzaglia, M; Miracoli, R; Neri, L; Torrisi, G; Altana, C; Ciavola, G

    2014-09-01

    The Versatile Ion Source (VIS) is a microwave discharge ion source installed at INFN-LNS and here used as test-bench for the production of high intensity low emittance proton beams and for studies on plasma physics. A series of measurements have been carried out with VIS in order to test the source with light ions. In particular a He(+) beam has been characterized in terms of plasma discharge parameters. The experiment has been triggered by the observation of X-radiation emission from the plasma for some configuration of the magnetic field profile. The plasma electron energy distribution function is in fact modified when in some regions of the plasma chamber under-resonance discharge takes place, fulfilling the condition that allows the electromagnetic wave to electrostatic wave conversion. These tests allowed obtaining more than 50 mA of He(+) beams.

  10. Characterization of Ag/Pt core-shell nanoparticles by UV-vis absorption, resonance light-scattering techniques.

    Science.gov (United States)

    Chen, Langxing; Zhao, Wenfeng; Jiao, Yufen; He, Xiwen; Wang, Jing; Zhang, Yukui

    2007-11-01

    The water-soluble Ag/Pt core-shell nanoparticles were prepared by deposition Pt over Ag colloidal seeds with the seed-growth method using K2PtCl4 with trisodium citrate as reduced agent. The Ag:Pt ratio is varied from 9:1 to 1:3 for synthesizing Pt shell layer of different thickness. A remarkable shift and broadening of Ag surface plasmon band around 410 nm was observed. The contrast of TEM images of Ag/Pt colloids has been obtained. Various techniques, such as transmission electron microscopy (TEM), UV-vis absorption and resonance light-scattering spectroscopy were used to characterize nanoparticles. The data of TEM, UV-vis and resonance light-scattering spectrum all confirm formation of Ag/Pt core-shell nanoparticles. Resonance light-scattering and emission spectrum show the Ag and Ag/Pt core-shell nanoparticles have a nonlinear light-scattering characteristic.

  11. Note: Enhanced production of He{sup +} from the Versatile Ion Source (VIS) in off-resonance configuration

    Energy Technology Data Exchange (ETDEWEB)

    Castro, G.; Mascali, D.; Celona, L.; Gammino, S.; Mazzaglia, M.; Neri, L.; Altana, C.; Ciavola, G. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Caliri, C. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, V. S. Sofia 64, 95123 Catania (Italy); Bartolo, F. Di [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Facoltà di Scienze MM.FF.NN., Università degli Studi di Messina, V.le F. Stagno D’Alcontres 31, 98166 S. Agata-Messina (Italy); Lanaia, D. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); CERN, Geneva (Switzerland); Miracoli, R. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); ESS Bilbao, Bilbao (Spain); Torrisi, G. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); DIIES, Università Mediterranea di Reggio Calabria, Via Graziella, I-89100 Reggio Calabria (Italy)

    2014-09-15

    The Versatile Ion Source (VIS) is a microwave discharge ion source installed at INFN-LNS and here used as test-bench for the production of high intensity low emittance proton beams and for studies on plasma physics. A series of measurements have been carried out with VIS in order to test the source with light ions. In particular a He{sup +} beam has been characterized in terms of plasma discharge parameters. The experiment has been triggered by the observation of X-radiation emission from the plasma for some configuration of the magnetic field profile. The plasma electron energy distribution function is in fact modified when in some regions of the plasma chamber under-resonance discharge takes place, fulfilling the condition that allows the electromagnetic wave to electrostatic wave conversion. These tests allowed obtaining more than 50 mA of He{sup +} beams.

  12. Evaluation of the release characteristics of covalently attached or electrostatically bound biocidal polymers utilizing SERS and UV-Vis absorption

    Directory of Open Access Journals (Sweden)

    G. N. Mathioudakis

    2016-09-01

    Full Text Available In this work, biocidal polymers with antimicrobial quaternized ammonium groups introduced in the polymer biocidal chains either through covalent attachment or electrostatic interaction have been separately incorporated in a poly (methyl methacrylate polymer matrix. The objective of present study was to highlight the release characteristics of biocidal polymers, primarily in saline but also in water ethanol solutions, utilizing UV-Vis absorption and Surface Enhanced Raman Scattering (SERS. It is shown that through the combination of UV-Vis and SERS techniques, upon the release process, it is possible the discrimination of the polymeric backbone and the electrostatically bound biocidal species. Moreover, it is found that electrostatically bound and covalently attached biocidal species show different SERS patterns. The long term aim is the development of antimicrobial polymeric materials containing both ionically bound and covalently attached quaternary ammonium thus achieving a dual functionality in a single component polymeric design.

  13. Optimization, validation and application of UV-Vis spectrophotometric-colorimetric methods for determination of trimethoprim in different medicinal products

    OpenAIRE

    Goran Stojković; Elizabeta Dimitrieska-Stojković; Marija Soklevska; Romel Velev

    2016-01-01

    Two simple, sensitive, selective, precise, and accurate methods for determination of trimethoprim in different sulfonamide formulations intended for use in human and veterinary medicine were optimized and validated. The methods are based on the trimethoprim reaction with bromcresol green (BCG) and 2,4-dinitro-1-fluorobenzene (DNFB). As extraction solvents we used 10 % N,N-dimethylacetamide in methanol and acetone for both methods, respectively. The colored products are quantified applying vis...

  14. Inter-laboratory comparisons of hexenuronic acid measurements in kraft eucalyptus pulps using a UV-Vis spectroscopic method

    Science.gov (United States)

    J.Y. Zhu; H.F Zhou; Chai X.S.; Donna Johannes; Richard Pope; Cristina Valls; M. Blanca Roncero

    2014-01-01

    An inter-laboratory comparison of a UV-Vis spectroscopic method (TAPPI T 282 om-13 “Hexeneuronic acid content of chemical pulp”) for hexeneuronic acid measurements was conducted using three eucalyptus kraft pulps. The pulp samples were produced in a laboratory at kappa numbers of approximately 14, 20, and 35. The hexeneuronic acid contents of the three pulps were...

  15. Roles of manganese oxides in degradation of phenol under UV-Vis irradiation: adsorption, oxidation, and photocatalysis.

    Science.gov (United States)

    Zhang, Qin; Cheng, Xiaodi; Zheng, Chen; Feng, Xionghan; Qiu, Guohong; Tan, Wenfeng; Liu, Fan

    2011-01-01

    Manganese oxides are known as one type of semiconductors, but their photocatalysis characteristics have not been deeply explored. In this study, photocatalytic degradation of phenol using several synthesized manganese oxides, i.e, acidic birnessite (BIR-H), alkaline birnessite (BIR-OH), cryptomelane (CRY) and todorokite (TOD), were comparatively investigated. To elucidate phenol degradation mechanisms, X-ray diffraction (XRD), ICP-AES (inductively coupled plasma-atomic emission spectroscopy), TEM (transmission electronic microscope), N2 physisorption at 77 K and UV-visible diffuse reflectance spectroscopy (UV-Vis DRS) were employed to characterize the structural, compositional, morphological, specific surface area and optical absorption properties of the manganese oxides. After 12 hr of UV-Vis irradiation, the total organic carbon (TOC) removal rate reached 62.1%, 43.1%, 25.4%, and 22.5% for cryptomelane, acidic birnessite, todorokite and alkaline birnessite, respectively. Compared to the reactions in the dark condition, UV-Vis exposure improved the TOC removal rates by 55.8%, 31.9%, 23.4% and 17.9%. This suggests a weak ability of manganese oxides to degrade phenol in the dark condition, while UV-Vis light irradiation could significantly enhance phenol degradation. The manganese minerals exhibited photocatalytic activities in the order of: CRY > BIR-H > TOD > BIR-OH. There may be three possible mechanisms for photochemical degradation: (1) direct photolysis of phenol; (2) direct oxidation of phenol by manganese oxides; (3) photocatalytic oxidation of phenol by manganese oxides. Photocatalytic oxidation of phenol appeared to be the dominant mechanism.

  16. A novel method for vicarious re-characterisation of the MVIRI VIS spectral response to facilitate climate monitoring

    OpenAIRE

    Quast, Ralf; Govaerts, Yves; Rüthrich, Frank; Giering, Ralf

    2017-01-01

    The Meteosat Visible and Infrared (MVIRI) sensors on board Meteosat First Generation (MFG) geostationary satellites (1982 - today) acquire radiance every 30 minutes in a broad spectral band, ranging approximately from 0.4 to 1.1 µm and referred to as the visible (VIS) band.The original objective of the MFG programme was the acquisition of Earth images to provide the meteorological community with information on atmospheric circulation and weather. One of the objectives of the H2020 Fidelity an...

  17. A novel method for vicarious re-characterisation of the MVIRI VIS spectral response to facilitate climate monitoring

    OpenAIRE

    Quast, Ralf; Govarts, Yves; Rüthrich, Frank; Giering, Ralf

    2017-01-01

    The Meteosat Visible and Infrared (MVIRI) sensors on board Meteosat First Generation (MFG) geostationary satellites (1982 - today) acquire radiance every 30 minutes in a broad spectral band, ranging approximately from 0.4 to 1.1 μm and referred to as the visible (VIS) band. The original objective of the MFG programme was the acquisition of Earth images to provide the meteoro- logical community with information on atmospheric circulation and weather. One of the ...

  18. A menopausa na visão gerontológica = The menopause in the gerontologic view

    Directory of Open Access Journals (Sweden)

    Poli, Marcelino Espírito Hofmeister

    2010-01-01

    Conclusões: a menopausa é um fenômeno inserido no processo de envelhecimento feminino e traz consigo consequências biológicas, psicológicas e sociais importantes. Na visão contemporânea, a terapêutica associada aos sinais e sintomas relacionados à menopausa está cada vez mais personalizada de acordo com o perfil de estilo de vida e saúde da mulher

  19. Improved analysis of Monascus pigments based on their pH-sensitive UV-Vis absorption and reactivity properties.

    Science.gov (United States)

    Shi, Kan; Chen, Gong; Pistolozzi, Marco; Xia, Fenggeng; Wu, Zhenqiang

    2016-09-01

    Monascus pigments, a mixture of azaphilones mainly composed of red, orange and yellow pigments, are usually prepared in aqueous ethanol and analysed by ultraviolet-visible (UV-Vis) spectroscopy. The pH of aqueous ethanol used during sample preparation and analysis has never been considered a key parameter to control; however, this study shows that the UV-Vis spectra and colour characteristics of the six major pigments are strongly influenced by the pH of the solvent employed. In addition, the increase of solvent pH results in a remarkable increase of the amination reaction of orange pigments with amino compounds, and at higher pH (≥ 6.0) a significant amount of orange pigment derivatives rapidly form. The consequent impact of these pH-sensitive properties on pigment analysis is further discussed. Based on the presented results, we propose that the sample preparation and analysis of Monascus pigments should be uniformly performed at low pH (≤ 2.5) to avoid variations of UV-Vis spectra and the creation of artefacts due to the occurrence of amination reactions, and ensure an accurate analysis that truly reflects pigment characteristics in the samples.

  20. Forecasting of UV-Vis absorbance time series using artificial neural networks combined with principal component analysis.

    Science.gov (United States)

    Plazas-Nossa, Leonardo; Hofer, Thomas; Gruber, Günter; Torres, Andres

    2017-02-01

    This work proposes a methodology for the forecasting of online water quality data provided by UV-Vis spectrometry. Therefore, a combination of principal component analysis (PCA) to reduce the dimensionality of a data set and artificial neural networks (ANNs) for forecasting purposes was used. The results obtained were compared with those obtained by using discrete Fourier transform (DFT). The proposed methodology was applied to four absorbance time series data sets composed by a total number of 5705 UV-Vis spectra. Absolute percentage errors obtained by applying the proposed PCA/ANN methodology vary between 10% and 13% for all four study sites. In general terms, the results obtained were hardly generalizable, as they appeared to be highly dependent on specific dynamics of the water system; however, some trends can be outlined. PCA/ANN methodology gives better results than PCA/DFT forecasting procedure by using a specific spectra range for the following conditions: (i) for Salitre wastewater treatment plant (WWTP) (first hour) and Graz West R05 (first 18 min), from the last part of UV range to all visible range; (ii) for Gibraltar pumping station (first 6 min) for all UV-Vis absorbance spectra; and (iii) for San Fernando WWTP (first 24 min) for all of UV range to middle part of visible range.

  1. UV/Vis Study of the Alkali Salts of Poly(thiophen-3-ylacetic acid) in Water.

    Science.gov (United States)

    Hostnik, Gregor; Vlachy, Vojko; Bondarev, Dmitrij; Vohlídal, Jiří; Cerar, Janez

    2012-09-01

    UV/Vis spectroscopic investigation of aqueous solutions of regio-irregular poly(thiophen-3-ylacetic acid) (PTAA) with and without methyl-ester groups in the presence of sodium and lithium ions as counterions is presented. The samples were carefully purified and characterized with respect to molar mass and the amount of -COOH groups present. We examined how the UV/Vis spectra of solution change with aging of PTAA solution, polymer concentration, addition of low molecular weight salt, temperature, and some other parameters. We show that results crucially depend on whether the spectra are taken for freshly prepared or mature solutions. We demonstrate the validity of the Beer-Lambert law for PTANa, PTAA/Na, and PTAA/Li (aged solution), and violation of this law for PTANa/Me (fresh) solutions in water; the latter system is instead found to exhibit an isosbetic point at 402 nm. We prove that UV/Vis spectra of polythiophene derivatives in water depend on the "age" (time after dissolution) of the solution. The inconsistencies among the spectroscopic data found in literature, as also the discrepancies with our own measurements on PTAA-based systems are discussed.

  2. Interactive reconstructions of cranial 3D implants under MeVisLab as an alternative to commercial planning software.

    Science.gov (United States)

    Egger, Jan; Gall, Markus; Tax, Alois; Ücal, Muammer; Zefferer, Ulrike; Li, Xing; von Campe, Gord; Schäfer, Ute; Schmalstieg, Dieter; Chen, Xiaojun

    2017-01-01

    In this publication, the interactive planning and reconstruction of cranial 3D Implants under the medical prototyping platform MeVisLab as alternative to commercial planning software is introduced. In doing so, a MeVisLab prototype consisting of a customized data-flow network and an own C++ module was set up. As a result, the Computer-Aided Design (CAD) software prototype guides a user through the whole workflow to generate an implant. Therefore, the workflow begins with loading and mirroring the patients head for an initial curvature of the implant. Then, the user can perform an additional Laplacian smoothing, followed by a Delaunay triangulation. The result is an aesthetic looking and well-fitting 3D implant, which can be stored in a CAD file format, e.g. STereoLithography (STL), for 3D printing. The 3D printed implant can finally be used for an in-depth pre-surgical evaluation or even as a real implant for the patient. In a nutshell, our research and development shows that a customized MeVisLab software prototype can be used as an alternative to complex commercial planning software, which may also not be available in every clinic. Finally, not to conform ourselves directly to available commercial software and look for other options that might improve the workflow.

  3. Non-contact assessment of COD and turbidity concentrations in water using diffuse reflectance UV-Vis spectroscopy.

    Science.gov (United States)

    Agustsson, Jon; Akermann, Oliver; Barry, D Andrew; Rossi, Luca

    2014-08-01

    Water contamination is an important environmental concern underlining the need for reliable real-time information on contaminant concentrations in natural waters. Here, a new non-contact UV-Vis spectroscopic approach for monitoring contaminants in water, and especially wastewater, is proposed. Diffuse reflectance UV-Vis spectroscopy was applied to measure simultaneously the chemical oxygen demand (COD) and turbidity (TUR) concentrations in water. The measurements were carried out in the wavelength range from 200-1100 nm. The measured spectra were analysed using partial-least-squares (PLS) regression. The correlation coefficient between the measured and the reference concentrations of COD and TUR in the water samples were R(2) = 0.85 and 0.96, respectively. These results highlight the potential of non-contact UV-Vis spectroscopy for the assessment of water contamination. A system built on the concept would be able to monitor wastewater pollution continuously, without the need for laborious sample collection and subsequent laboratory analysis. Furthermore, since no parts of the system are in contact with the wastewater stream the need for maintenance is minimised.

  4. Application of UV/VIS spectrophotometry and multivariate analysis to characterization of the species of Solanum sect. Erythrotrichum CHILD.

    Science.gov (United States)

    Basílio, Ionaldo José L D; Moura, Renata K P; Bhattacharyya, Jnanabrata; de Fátima Agra, Maria

    2012-06-01

    The UV/VIS spectral characteristics of the standardized extracts of the leaves of 22 Solanum species of the Leptostemonum clade were investigated in the presence of shift reagents with the aid of multivariate analysis, to obtain data in support of the interspecific and subsectional delimitation proposed for Solanum sect. Erythrotrichum. Of these species, 20 belong to the section Erythrotrichum, S. paniculatum is assigned to the section Torva, and S. robustum is not attributed to a defined section. The results indicated characteristic λ(max) (absorbance maxima) for each species as well as the presence of phenolic compounds like flavonoids such as 5-hydroxy flavonols. Hierarchical cluster analysis (HCA) of the data obtained by UV/VIS analysis of the extracts or the extracts with the added shift reagents AlCl₃ and HCl showed a cophenetic correlation coefficient above 0.92 and the classification of the data into three groups. The principal-component analysis (PCA) revealed that the first three principal components accounted for over 98% of the total variance and showed results similar to those obtained by HCA. The present results supported the current proposal for interspecific delimitation of the studied species and partially supported the division of the section into two subsections. The UV/VIS spectral characteristics along with multivariate analysis appear to be a useful approach for distinguishing among species of the genus Solanum. Copyright © 2012 Verlag Helvetica Chimica Acta AG, Zürich.

  5. Interactive reconstructions of cranial 3D implants under MeVisLab as an alternative to commercial planning software.

    Directory of Open Access Journals (Sweden)

    Jan Egger

    Full Text Available In this publication, the interactive planning and reconstruction of cranial 3D Implants under the medical prototyping platform MeVisLab as alternative to commercial planning software is introduced. In doing so, a MeVisLab prototype consisting of a customized data-flow network and an own C++ module was set up. As a result, the Computer-Aided Design (CAD software prototype guides a user through the whole workflow to generate an implant. Therefore, the workflow begins with loading and mirroring the patients head for an initial curvature of the implant. Then, the user can perform an additional Laplacian smoothing, followed by a Delaunay triangulation. The result is an aesthetic looking and well-fitting 3D implant, which can be stored in a CAD file format, e.g. STereoLithography (STL, for 3D printing. The 3D printed implant can finally be used for an in-depth pre-surgical evaluation or even as a real implant for the patient. In a nutshell, our research and development shows that a customized MeVisLab software prototype can be used as an alternative to complex commercial planning software, which may also not be available in every clinic. Finally, not to conform ourselves directly to available commercial software and look for other options that might improve the workflow.

  6. xVis: a web server for the schematic visualization and interpretation of crosslink-derived spatial restraints.

    Science.gov (United States)

    Grimm, Maximilian; Zimniak, Tomasz; Kahraman, Abdullah; Herzog, Franz

    2015-07-01

    The identification of crosslinks by mass spectrometry has recently been established as an integral part of the hybrid structural analysis of protein complexes and networks. The crosslinking analysis determines distance restraints between two covalently linked amino acids which are typically summarized in a table format that precludes the immediate and comprehensive interpretation of the topological data. xVis displays crosslinks in clear schematic representations in form of a circular, bar or network diagram. The interactive graphs indicate the linkage sites and identification scores, depict the spatial proximity of structurally and functionally annotated protein regions and the evolutionary conservation of amino acids and facilitate clustering of proteins into subcomplexes according to the crosslink density. Furthermore, xVis offers two options for the qualitative assessment of the crosslink identifications by filtering crosslinks according to identification scores or false discovery rates and by displaying the corresponding fragment ion spectrum of each crosslink for the manual validation of the mass spectrometric data. Our web server provides an easy-to-use tool for the fast topological and functional interpretation of distance information on protein complex architectures and for the evaluation of crosslink fragment ion spectra. xVis is available under a Creative Commons Attribution-ShareAlike 4.0 International license at http://xvis.genzentrum.lmu.de/. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  7. [BPNN simulation of photocatalytic degradation of reactive scarlet BES by UV-Vis spectrophotometer].

    Science.gov (United States)

    Zhang, Yun-Tao; He, Guo-Li; Xiang, Ming-Li

    2009-10-01

    The use of chemometric techniques and multivariate experimental designs for the photocatalytic reaction of reactive scarlet BES in aqueous solution under ultraviolet light irradiation is described. The efficiency of photocatalytic degradation was evaluated by the analysis of the parameter of decoloration efficiency determined by UV absorption at 540 nm using a UV-Vis spectrophotometer in different conditions. Five factors, such as the amount of titanium oxide ([TiO2]), the concentrations of reactive scarlet BES (c(0)), irradiation time (t), the pH value (pH) and temperature (T), were studied. [TiO2]. c(0), t and pH selected on the basis of the results of variance analysis by Plackett-Burman design were used as independent variables. Training sets and test sets of back propagation neural network (BPNN) were formed by Box-Behnken design and uniform design U10 (10 x 5(2) x 2) respectively. The process of photocatalytic degradation of the target object was simulated by the BPNN model. The correlation coefficient (r) of the calculation results for training set and test set by BPNN is 0.996 4 and 0.963 6 respectively, and the mean relative errors between the predictive value and experimental value of decoloration efficiency are 6.14 and 7.76, respectively. The modeled BPNN was applied to analyze the influence of four factors on decoloration efficiency. The results showed that the initial conditions of c(0) being lower, pH 5.0 and appropriate amount of [TiO2] contribute to improving the decoloration efficiency of reactive scarlet BES. Under the condition of c(0) = 40 mg x L(-1), the optimized experimental condition of the system was obtained: [TiO2] = 1.20 g x L(-1) and pH 5.0. Under the optimized experimental condition, the experimental value of decoloration efficiency is 98.20% when irradiation time is 35 minutes and the predictive value of decoloration efficiency is 99.16% under the same condition. The relative error of decoloration efficiency between the predictive

  8. Adaptações curriculares para o ensino-aprendizagem de alunos com baixa visão

    Directory of Open Access Journals (Sweden)

    Ricardo Souza da Silva

    2015-04-01

    Full Text Available A visão é um dos sentidos mais importante para o ser humano é através dela que se obtém uma imagem integrada do mundo, é responsável por cerca de oitenta e cinco por cento das informações que recebemos, por meio dela apreendemos o mundo. A visão reduzida causa inúmeros prejuízos à pessoa, a área mais afetada é a aprendizagem. Considerando que o aluno com baixa visão necessita de adaptações pedagógicas nos diferentes aspectos da organização do espaço escolar, neste trabalho se buscou verificar as adaptações curriculares realizadas no interior da sala de aula comum e em atendimento especializado para deficiência visual, pertencentes a rede municipal de ensino de Sinop/MT. Constatou-se que a inclusão e atendimento ao aluno com deficiência visual, não corresponde ao discurso político e pedagógico do Plano Municipal de Educação de Sinop. Vários fatores contribuem para a não efetivação deste modelo de educação, dentre eles: acessibilidade física, escassez ou inexistência de materiais pedagógicos adaptados, falta de recursos tecnológicos e ópticos, inadequação do mobiliário, iluminação precária, paredes escuras e sujas, espaços pequenos, destinação à escola de verbas insuficientes para as adaptações necessárias, morosidade no cadastro do aluno no censo escolar nacional, e ainda, instalações provisórias e improvisadas, alocadas para funcionamento de salas de aula, inadequadas, principalmente para o aluno com baixa visão. Palavras-chave: educação; educação especial; baixa visão; adaptações curriculares; aprendizagem.

  9. Face validity of VIS-Ed: a visualization program for teaching medical students and residents the biomechanics of cervical spine trauma.

    Science.gov (United States)

    Courteille, Olivier; Ho, Johnson; Fahlstedt, Madelen; Fors, Uno; Felländer-Tsai, Li; Hedman, Leif; Möller, Hans

    2013-01-01

    This RCT study aimed to investigate if VIS-Ed (Visualization through Imaging and Simulation - Education) had the potential to improve medical student education and specialist training in clinical diagnosis and treatment of trauma patients. The participants' general opinion was reported as high in both groups (lecture vs. virtual patient (VP)). Face validity of the VIS-Ed for cervical spine trauma was demonstrated and the VP group reported higher stimulation and engagement compared to the lecture group. No significant difference in the knowledge test between both groups could be observed, confirming our null hypothesis that VIS-Ed was on par with a lecture.

  10. Ozone retrievals from MAGEAQ GEO TIR+VIS for air quality

    Science.gov (United States)

    Quesada-Ruiz, Samuel; Attié, Jean-Luc; Lahoz, William A.; Abida, Rachid; El-Amraoui, Laaziz; Ricaud, Philippe; Zbinden, Regina; Spurr, Robert; da Silva, Arlindo M.

    2016-04-01

    Nowadays, air quality monitoring is based on the use of ground-based stations (GBS) or satellite measurements. GBS provide accurate measurements of pollutant concentrations, especially in the planetary boundary layer (PBL), but usually the spatial coverage is sparse. Polar-orbiting satellites provide good spatial resolution but low temporal coverage -this is insufficient for tracking pollutants exhibiting a diurnal cycle (Lahoz et al., 2012). However, pollutant concentrations can be measured by instruments placed on board a geostationary satellite, which can provide sufficiently high temporal and spatial resolutions (e.g. Hache et al., 2014). In this work, we investigate the potentiality of a possible future geostationary instrument, MAGEAQ (Monitoring the Atmosphere from Geostationary orbit for European Air Quality), for retrieving ozone measurements over Europe. In particular, MAGEAQ can provide 1-hour temporal sampling at 10x10km pixel resolution for measurements in both visible (VIS) and thermal infrared (TIR) bands -thus, we will be able to measure during the day and at night. MAGEAQ synthetic radiance observations are obtained through radiative transfer (RT) simulations using the VLIDORT discrete ordinate RT model (Spurr, 2006) based on output from the GEOS-5 Nature Run (Gelaro et al., 2015) providing optical information, plus a suitable instrument model. Ozone is retrieved from these synthetic measurements using the optimal estimation inversion scheme of Levenberg-Marquardt. Finally, we examine an application of the air quality concept based on these ozone retrievals during the heatwave event of July 2006 over Europe. REFERENCES Gelaro, R., Putman, W. M., Pawson, S., Draper, C., Molod, A., Norris, P. M., Ott, L., Privé, N., Reale, O., Achuthavarier, D., Bosilovich, M., Buchard, V., Chao, W., Coy, L., Cullather, R., da Silva, A., Darmenov, A., Errico, R. M., Fuentes, M., Kim, M-J., Koster, R., McCarty, W., Nattala, J., Partyka, G., Schubert, S., Vernieres, G

  11. Vis-NIR characterization of particulate matter in urban and industrial sites in the Mediterranean area

    Science.gov (United States)

    Salzano, R.; Montagnoli, M.; Salvatori, R.; Perrino, C.

    2010-12-01

    The optical properties of particulate matter are key parameters for the definition of the radiative balance of the atmosphere and require a deeper comprehension for improving modelling. Considering the cognitive gap evidenced by IPCC guidelines, additional tools are necessary for understanding how size distribution and mineralogy contribute to the complexity of a matrix such as particulate matter. Knowing that concentration and chemical composition are nowadays features that are “traditionally” investigated, the role of mineralogy and size distribution on the physico-chemical behaviour of airborne particles represent evidently primary goals for emerging approaches. From this point of view Vis-NIR spectroscopy could be considered an innovative technique. It is in fact a non-destructive and a relatively low-cost technique that provide information on the optical properties of materials. It is largely applied for Earth sciences purposes (for example: Pedology, Geology and Remote sensing) and requires a “calibration” with chemical or physical parameters. The difference between this technique and already developed methods (such as Aethalometry or other optical systems) consists on the simultaneous investigation of several wavelengths of the visible and near infrared regions instead of single bands. The development of this approach, focused on the relationship between light scattering and properties of materials, can provide important knowledge on the mineralogical composition of airborne particles and on the size distribution of particles. In addition of that the development of a database, constituted by airborne materials collected in different sites, can represent the link between remote or ground observations, radiative modelling and in situ sampling. The work carried out until now is based on field campaigns performed in the Mediterranean basin where PM10 and PM2.5 samples were collected in urban, traffic, industrial and background sites. Samples were

  12. Development and validation of a FIA/UV-vis method for pK(a) determination of oxime based acetylcholinesterase reactivators.

    Science.gov (United States)

    Musil, Karel; Florianova, Veronika; Bucek, Pavel; Dohnal, Vlastimil; Kuca, Kamil; Musilek, Kamil

    2016-01-05

    Acetylcholinesterase reactivators (oximes) are compounds used for antidotal treatment in case of organophosphorus poisoning. The dissociation constants (pK(a1)) of ten standard or promising acetylcholinesterase reactivators were determined by ultraviolet absorption spectrometry. Two methods of spectra measurement (UV-vis spectrometry, FIA/UV-vis) were applied and compared. The soft and hard models for calculation of pK(a1) values were performed. The pK(a1) values were recommended in the range 7.00-8.35, where at least 10% of oximate anion is available for organophosphate reactivation. All tested oximes were found to have pK(a1) in this range. The FIA/UV-vis method provided rapid sample throughput, low sample consumption, high sensitivity and precision compared to standard UV-vis method. The hard calculation model was proposed as more accurate for pK(a1) calculation. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. UV/VIS SPECTROMETER DETERMINATION OF CAFFEINE IN GREEN COFFEE BEANS FROM HARARGHE, ETHIOPIA, USING BEER-LAMBERT'S LAW AND INTEGRATED ABSORPTION COEFFICIENT TECHNIQUES

    National Research Council Canada - National Science Library

    Ephrem G Demissie; Girma W Woyessa; Arayaselassie Abebe

    2016-01-01

      A total of fifteen samples of green coffee (Coffea arabica L.) beans from the major producing region of Hararghe Ethiopia were studied using UV-Vis spectrometer measurement caffeine quantitative analysis from coffee beans...

  14. UV/VIS SPECTROMETER DETERMINATION OF CAFFEINE IN GREEN COFFEE BEANS FROM HARARGHE, ETHIOPIA, USING BEER-LAMBERT’S LAW AND INTEGRATED ABSORPTION COEFFICIENT TECHNIQUES

    National Research Council Canada - National Science Library

    EPHREM G. DEMISSIE; GIRMA W. WOYESSA; ARAYASELASSIE ABEBE

    2016-01-01

    A total of fifteen samples of green coffee (Coffea arabica L.) beans from the major producing region of Hararghe Ethiopia were studied using UV-Vis spectrometer measurement caffeine quantitative analysis from coffee beans...

  15. AquaScan: A miniaturized UV/VIS/IR hyperspectral imager for autonomous airborne and underwater imaging spectroscopy of coastal & oceanic environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AquaScan, a miniaturized UV/VIS/NIR hyperspectral imager will be built for deployment on a UAV or small manned aircraft for ocean coastal remote sensing...

  16. visPIG--a web tool for producing multi-region, multi-track, multi-scale plots of genetic data.

    Directory of Open Access Journals (Sweden)

    Matthew Scales

    Full Text Available We present VISual Plotting Interface for Genetics (visPIG; http://vispig.icr.ac.uk, a web application to produce multi-track, multi-scale, multi-region plots of genetic data. visPIG has been designed to allow users not well versed with mathematical software packages and/or programming languages such as R, Matlab®, Python, etc., to integrate data from multiple sources for interpretation and to easily create publication-ready figures. While web tools such as the UCSC Genome Browser or the WashU Epigenome Browser allow custom data uploads, such tools are primarily designed for data exploration. This is also true for the desktop-run Integrative Genomics Viewer (IGV. Other locally run data visualisation software such as Circos require significant computer skills of the user. The visPIG web application is a menu-based interface that allows users to upload custom data tracks and set track-specific parameters. Figures can be downloaded as PDF or PNG files. For sensitive data, the underlying R code can also be downloaded and run locally. visPIG is multi-track: it can display many different data types (e.g association, functional annotation, intensity, interaction, heat map data,…. It also allows annotation of genes and other custom features in the plotted region(s. Data tracks can be plotted individually or on a single figure. visPIG is multi-region: it supports plotting multiple regions, be they kilo- or megabases apart or even on different chromosomes. Finally, visPIG is multi-scale: a sub-region of particular interest can be 'zoomed' in. We describe the various features of visPIG and illustrate its utility with examples. visPIG is freely available through http://vispig.icr.ac.uk under a GNU General Public License (GPLv3.

  17. H-aggregate analysis of P3HT thin films-Capability and limitation of photoluminescence and UV/Vis spectroscopy

    OpenAIRE

    Philipp Ehrenreich; Susanne T. Birkhold; Eugen Zimmermann; Hao Hu; Kwang-Dae Kim; Jonas Weickert; Thomas Pfadler; Lukas Schmidt-Mende

    2016-01-01

    Polymer morphology and aggregation play an essential role for efficient charge carrier transport and charge separation in polymer-based electronic devices. It is a common method to apply the H-aggregate model to UV/Vis or photoluminescence spectra in order to analyze polymer aggregation. In this work we present strategies to obtain reliable and conclusive information on polymer aggregation and morphology based on the application of an H-aggregate analysis on UV/Vis and photoluminescence spect...

  18. visPIG--a web tool for producing multi-region, multi-track, multi-scale plots of genetic data.

    Science.gov (United States)

    Scales, Matthew; Jäger, Roland; Migliorini, Gabriele; Houlston, Richard S; Henrion, Marc Y R

    2014-01-01

    We present VISual Plotting Interface for Genetics (visPIG; http://vispig.icr.ac.uk), a web application to produce multi-track, multi-scale, multi-region plots of genetic data. visPIG has been designed to allow users not well versed with mathematical software packages and/or programming languages such as R, Matlab®, Python, etc., to integrate data from multiple sources for interpretation and to easily create publication-ready figures. While web tools such as the UCSC Genome Browser or the WashU Epigenome Browser allow custom data uploads, such tools are primarily designed for data exploration. This is also true for the desktop-run Integrative Genomics Viewer (IGV). Other locally run data visualisation software such as Circos require significant computer skills of the user. The visPIG web application is a menu-based interface that allows users to upload custom data tracks and set track-specific parameters. Figures can be downloaded as PDF or PNG files. For sensitive data, the underlying R code can also be downloaded and run locally. visPIG is multi-track: it can display many different data types (e.g association, functional annotation, intensity, interaction, heat map data,…). It also allows annotation of genes and other custom features in the plotted region(s). Data tracks can be plotted individually or on a single figure. visPIG is multi-region: it supports plotting multiple regions, be they kilo- or megabases apart or even on different chromosomes. Finally, visPIG is multi-scale: a sub-region of particular interest can be 'zoomed' in. We describe the various features of visPIG and illustrate its utility with examples. visPIG is freely available through http://vispig.icr.ac.uk under a GNU General Public License (GPLv3).

  19. Tantalum (oxy)nitrides nanotube arrays for the degradation of atrazine in vis-Fenton-like process.

    Science.gov (United States)

    Du, Yingxun; Zhao, Lu; Chang, Yuguang; Su, Yaling

    2012-07-30

    In order to overcome the limitation of the application of nanoparticles, tantalum (oxy)nitrides nanotube arrays on a Ta foil were synthesized and introduced in vis (visible light)-Fenton-like system to enhance the degradation of atrazine. At first, the anodization of tantalum foil in a mild electrolyte solution containing ethylene glycol and water (v:v=2:1) plus 0.5wt.% NH(4)F produced tantala nanotubes with an average diameter of 30nm and a length of approximately 1μm. Then the nitridation of tantala nanotube arrays resulted in the replacement of N atoms to O atoms to form tantalum (oxy)nitrides (TaON and Ta(3)N(5)), as testified by XRD and XPS analyses. The synthesized tantalum (oxy)nitrides nanotubes absorb well in the visible region up to 600nm. Under visible light, tantalum (oxy)nitrides nanotube arrays were catalytically active for Fe(3+) reduction. With tantalum (oxy)nitrides nanotube arrays, the degradation of atrazine and the formation of the intermediates in vis/Fe(3+)/H(2)O(2) system were significantly accelerated. This was explained by the higher concentration of Fe(2+) and thus the faster decomposition of H(2)O(2) with tantalum (oxy)nitrides nanotubes. In addition, tantalum (oxy)nitrides nanotubes exhibited stable performance during atrazine degradation for three runs. The good performance and stability of the tantalum (oxy)nitrides nanotubes film with the convenient separation, suggest that this film is a promising catalyst for vis-Fenton-like degradation. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Educação, um processo de humanização na visão frankliana

    Directory of Open Access Journals (Sweden)

    Emiliana Aparecida de Souza

    2013-12-01

    Full Text Available A educação tem um papel fundamental no desenvolvimento dos indivíduos e das sociedades, não só como transmissora de conhecimentos como meio para alcançar um fim, mas como formadora de um ser humano que responda aos seus anseios de profundidade com sentido. Este estudo objetiva investigar a noção de educação, não só como ensinamentos, mas também como promotora do desenvolvimento humano na Análise Existencial de Viktor Frankl, na visão de homem que ele transmite e buscar compreender a relevância da Análise Existencial para a educação. Fundamenta-se esse trabalho, em uma revisão bibliográfica de publicações e textos científicos. A Análise Existencial de Frankl e sua visão de homem, que compreende o ser humano como uma unidade antropológica, embora se considerem as diferentes dimensões de tipo ontológico, estão em oferecer uma contribuição intelectual que pode melhor promover relações interpessoais, reumanização da educação e da ciência em geral. Recibido: 09/01/2013 / Aceptado: 15/01/2013Cómo referenciar este artículoAparecida de Souza, E.; Salvino Gomes, E. (2013. Educação, um processo de humanização na visão frankliana. Foro de Educación, 11(15, pp. 215-228. doi: http://dx.doi.org/10.14516/fde.2013.011.015.010

  1. The effect of different propolis harvest methods on its lead contents determined by ET AAS and UV-visS

    Energy Technology Data Exchange (ETDEWEB)

    Sales, A. [Department of Analytical Chemistry, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucuman, Ayacucho 471, 4000 Tucuman (Argentina)]. E-mail: amsales@fbqf.unt.edu.ar; Alvarez, A. [National Institute of Agricultural Technology (INTA), Experimental Station Famailla, Ruta 301, Km 32, Famailla, Tucuman (Argentina); Areal, M. Rodriguez [Department of Analytical Chemistry, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucuman, Ayacucho 471, 4000 Tucuman (Argentina); Maldonado, L. [National Institute of Agricultural Technology (INTA), Experimental Station Famailla, Ruta 301, Km 32, Famailla, Tucuman (Argentina); Marchisio, P. [Department of Analytical Chemistry, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucuman, Ayacucho 471, 4000 Tucuman (Argentina); Rodriguez, M. [Department of Analytical Chemistry, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucuman, Ayacucho 471, 4000 Tucuman (Argentina); Bedascarrasbure, E. [National Institute of Agricultural Technology (INTA), Experimental Station Famailla, Ruta 301, Km 32, Famailla, Tucuman (Argentina)

    2006-10-11

    Argentinean propolis is exported to different countries, specially Japan. The market demands propolis quality control according to international standards. The analytical determination of some metals, as lead in food, is very important for their high toxicity even in low concentrations and because of their harmful effects on health. Flavonoids, the main bioactive compounds of propolis, tend to chelate metals as lead, which becomes one of the main polluting agents of propolis. The lead found in propolis may come from the atmosphere or it may be incorporated in the harvest, extraction and processing methods. The aim of this work is to evaluate lead level on Argentinean propolis determined by electrothermal atomic absorption spectrometry (ET AAS) and UV-vis spectrophotometry (UV-visS) methods, as well as the effect of harvest methods on those contents. A randomized test with three different treatments of collection was made to evaluate the effect of harvest methods. These procedures were: separating wedges (traditional), netting plastic meshes and stamping out plastic meshes. By means of the analysis of variance technique for multiple comparisons (ANOVA) it was possible to conclude that there are significant differences between scraped and mesh methods (stamped out and mosquito netting meshes). The results obtained in the present test would allow us to conclude that mesh methods are more advisable than scraped ones in order to obtain innocuous and safe propolis with minor lead contents. A statistical comparison of lead determination by both, ET AAS and UV-visS methods, demonstrated that there is not a significant difference in the results achieved with the two analytical techniques employed.

  2. Micro-Raman and UV-VIS Studies of 100 MeV Ni4+ Irradiated Cadmium Telluride Thin Films

    OpenAIRE

    Neelam Pahwa; A.D. Yadav; Dubey, S.K.; Patel, A. P.

    2011-01-01

    CdTe thin films grown by thermal evaporation on quartz substrates were irradiated with Swift (100 MeV) Ni 4 + ions for fluences in the range 1.0 × 1011 - 1.0 × 1013 cm – 2. The modification in the structure and optical properties has been studied as a function of ion fluence using Micro-Raman spectroscopy and UV-VIS spectroscopy. In Micro Raman spectrum, weak LO and TO modes of CdTe and A1 & E modes of Te were observed with blue shift which was found to increase with increase in fluence. Inte...

  3. Development of a UV/Vis spectrophotometric method for analysis of total polyphenols from Caesalpinia peltophoroides Benth

    Directory of Open Access Journals (Sweden)

    Fernanda G. Bueno

    2012-01-01

    Full Text Available Caesalpinia peltophoroides is a domesticated tree found in Brazil. It was necessary to develop an analytical method to determine the content of total polyphenols (TP in this herbal drug. The pre-analytical method was standardized for analysis time, wavelength, and the best standard to use. The optimum conditions were: pyrogallol, 760 nm, and 30 min respectively. Under these conditions, validation by UV/Vis spectrophotometry proved to be reliable for TP of the crude extract and semipurified fractions from C. peltophoroides. Standardization is required for every herbal drug, and this method proved to be linear, precise, accurate, reproducible, robust, and easy to perform.

  4. Effects of slash-and-burn land management on soil spectral properties estimated with VIS-NIR-SWIR spectroscopy

    Science.gov (United States)

    Rosero-Vlasova, Olga Alexandra; Vlassova, Lidia; Rosero Tufiño, Pedro; Pérez-Cabello, Fernando; Montorio Llovería, Raquel

    2017-04-01

    Slash-and-burn land management is typical for low-income tropical countries, such as Ecuador. It involves conversion of forest into areas used for agriculture. At first trees are cut and the wood debris is burnt. After initial clearing, biomass burning is performed after each production cycle. Usually, cultivation cycles are followed by the fallow period. In the medium and long term, these practices have negative effect on soil fertility and there is the need for clearing more forest for agricultural use. This is one of the reasons for continuing deforestation with the consequent loss of biodiversity. Changes in physico-chemical properties due to periodic burning are accompanied by changes in soil spectral properties and can be determined using VIS-NIR-SWIR spectroscopy, which can be a cost-effective alternative for traditional methods of soil analysis. The purpose of the study is to assess the viability of VIS-NIR-SWIR spectroscopy for characterization of soils from land areas under slash-and-burn management system. Eighteen samples from soil surface layer were collected from two corn fields in the province of Los Rios, Ecuador, in September 2015. One of the areas has experienced six slash-and-burn cycles, while in the other the samples were collected at the end of the first corn cultivation cycle. Spectral measurements of sieved and air-dried samples were performed in the laboratory of the University of Zaragoza using ASD Fieldspec®4 spectroradiometer (350-2500nm spectral range) and ASD Illuminator Lamp as a light source. Statistically significant differences were observed between soil spectra of the samples from two soil groups. Reflectance of repeatedly burnt soils was 20% higher (mean value for the entire spectrum) for 65% of the samples, being especially important in VIS (>45%) and NIR ( 35%), probably due to the lower organic matter (OM) content. OM models built using Partial least Squares Regression demonstrated high predictive capacity (R2>0.8). Thus, the

  5. Vis-NIR Hyperspectral and Terahertz Imaging Investigations on a Fresco Painting on "Tavella" by Alessandro Gherardini

    Science.gov (United States)

    Doria, A.; Gallerano, G. P.; Giovenale, E.; Casini, A.; Cucci, C.; Picollo, M.; Poggesi, M.; Stefani, L.; Fukunaga, K.; Tamassia, M.

    2017-04-01

    In this paper, we report on Vis-IR hyperspectral and terahertz imaging investigations carried out on a fresco painting on tavella depicting St. John Baptist, by Alessandro Gherardini (1655-1726). Measurements took place at the Restoration Laboratories of the former "Polo Museale della Toscana," in Florence, in the framework of the Italy-Japan collaborative project THz-ARTE. We show how the hyperspectral data made it possible to determine the state-of-conservation of Gherardini's painting, while reflection imaging measurements performed at 97 GHz provided a qualitative evaluation of the position of defects inside the tavella.

  6. UV-Vis optoelectronic properties of α-SnWO4: A comparative experimental and density functional theory based study

    KAUST Repository

    Ziani, Ahmed

    2015-09-03

    We report a combined experimental and theoretical study on the optoelectronic properties of α-SnWO4 for UV-Vis excitation. The experimentally measured values for thin films were systematically compared with high-accuracy density functional theory and density functional perturbation theory using the HSE06 functional. The α-SnWO4 material shows an indirect bandgap of 1.52 eV with high absorption coefficient in the visible-light range (>2 × 105 cm−1). The results show relatively high dielectric constant (>30) and weak diffusion properties (large effective masses) of excited carriers.

  7. La espectrofotometría UV-VIS aplicada al estudio del color y estabilidad en morteros coloreados

    OpenAIRE

    Alejandre, F. J.

    1999-01-01

    Dentro de las metodologías existentes para el estudio del color, se ha realizado una investigación del mismo en morteros coloreados por medio de la espectrofotometría UV-VIS, técnica instrumental que es adaptable al trabajo con materiales sólidos, y que ha sido aplicada anteriormente en el estudio de diversos materiales de construcción. Los resultados obtenidos muestran cómo la citada técnica permite además de evaluar cualitativamente y cuantitativamente los colores de forma sencilla y objeti...

  8. Parâmetros de avaliação da visão: os campos visuais

    OpenAIRE

    Poças, Ilda

    2015-01-01

    Campo visual - Zona do espaço perceptível por um olho fixo, toda a área que é visível com os olhos fixados num determinado ponto, área passível de ser vista para a frente, para os lados (direito e esquerdo), para cima e para baixo, quando o olho se encontra imóvel num ponto fixo. Pode ser monocular (um só olho) ou binocular (os dois olhos simultaneamente.

  9. Estudio por espectrofotometria uv-vis de la reacción entre los iones cianuro y el picrato. un ejemplo práctico de aplicaciones analiticas y estudios cinéticos

    OpenAIRE

    Oliveros-Bastidas, Alberto de J; Carrera, Ceferino A.; Marín, David

    2009-01-01

     La cinética de la reacción entre el ión cianuro y el picrato de sodio se estudió por espectrofotometría UV-Vis. Se observó una reacción de orden uno para ambos reactivos, así como un desplazamiento batocrómico de la señal de máxima absorbancia, incrementando la concentración de cualquiera de los reactivos, asociada a la formación de complejos de diferente estequiometría y resultando en los consiguientes cambios en los parámetros espectrométricos. Estos resultados sustentan una interacción de...

  10. Application of Genetic Algorithm in the Modeling of Leaf Chlorophyll Level Based on Vis/Nir Reflection Spectroscopy

    Science.gov (United States)

    Yang, Haiqing; Yang, Haiqing; He, Yong

    In order to detect leaf chlorophyll level nondestructively and instantly, VIS/NIR reflection spectroscopy technique was examined. In the test, 70 leaf samples were collected for model calibration and another 50 for model verification. Each leaf sample was optically measured by USB4000, a modular spectrometer. By the observation of spectral curves, the spectral range between 650nm and 750nm was found significant for mathematic modeling of leaf chlorophyll level. SPAD-502 meter was used for chemometrical measurement of leaf chlorophyll value. In the test, it was found necessary to put leaf thickness into consideration. The procedure of shaping the prediction model is as follows: First, leaf chlorophyll level prediction equation was created with uncertain parameters. Second, a genetic algorithm was programmed by Visual Basic 6.0 for parameter optimization. As the result of the calculation, the optimal spectral range was narrowed within 683.24nm and 733.91nm. Compared with the R2=0.2309 for calibration set and R2=0.5675 for on the spectral modeling is significant: the R2 of calibration set and verification set has been improved as high as 0.8658 and 0.9161 respectively. The test showed that it is practical to use VIS/NIR reflection spectrometer for the quantitative determination of leaf chlorophyll level.

  11. Characteristics of compounds in hops using cyclic voltammetry, UV-VIS, FTIR and GC-MS analysis.

    Science.gov (United States)

    Masek, Anna; Chrzescijanska, Ewa; Kosmalska, Anna; Zaborski, Marian

    2014-08-01

    The article presents the antioxidant properties of the extracts of hop EI and EII, by the electrochemical methods on a platinum electrode and comparative analysis of the composition of the extracts of hops using UV-VIS, FTIR and GC-MS methods. The hops extract EI, was obtained from the waste of the hops cone. The hops extract EII, was obtained from the hops cone itself. Hops contain a wide range of polyphenolic compounds with antioxidant properties divided in various chemical classes. Flavonoids and other polyphenolic compounds contained in hops show antioxidant capacity because of the presence of hydroxyl groups in various configurations and numbers within their molecules. The electrochemical properties and antioxidant capacity of hop samples were determined to select the most effective antioxidant. Based on the cyclic and pulse voltammograms, it was observed that hop extract EI contains polyphenols that are oxidised at a less positive potential than extract EII, i.e., it shows better antioxidant capacity. From the analysis of the UV-VIS and FTIR spectra and the GC-MS analysis, it was observed that extract EI contains less phenyl compounds than EII. In addition to flavonoids, EII contains hop acids and chlorophyll. The solutions of hop extracts show very good antioxidant capacities; therefore, they can effectively inhibit or slow negative oxidation reactions and scavenge free radicals and reactive oxygen species (ROS). Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Determination of antioxidant capacity of diverse fruits by electron spin resonance (ESR) and UV-vis spectrometries.

    Science.gov (United States)

    Zang, Shuang; Tian, Sizhu; Jiang, Jia; Han, Dandan; Yu, Xinyu; Wang, Kun; Li, Dan; Lu, Dayong; Yu, Aimin; Zhang, Ziwei

    2017-04-15

    Twenty-one kinds of fruits including strawberry, mulberry, lemon, banana, etc. were measured for antioxidant capacity based on their ability to scavenge 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical. Vitamin C equivalent antioxidant capacity (VCEAC) was used to quantify antioxidant capacity of the studied fruits. The results were expressed as mg of ascorbic acid equivalent per 100g fruit. Each fruit was divided into two parts: harvest part (fresh fruit analyzed immediately), and liquid nitrogen frozen part (fruit frozen and pulverized in liquid nitrogen). Antioxidant capacities of both fresh and frozen fruits were determined, and VCEAC values were proved to have no significant difference. For the frozen fruits, the antioxidant capacities were measured by electron spin resonance spectroscopy (ESR) and UV-vis spectrometry. VCEAC values obtained with UV-vis and ESR range from 11.48 to 345.75mg/100g and 7.01 to 366.26mg/100g. Experimental results indicated that VCEAC values obtained by two methods were highly correlated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Ultrafast Dynamics of Sb-Corroles: A Combined Vis-Pump Supercontinuum Probe and Broadband Fluorescence Up-Conversion Study

    Directory of Open Access Journals (Sweden)

    Clark Zahn

    2017-07-01

    Full Text Available Corroles are a developing class of tetrapyrrole-based molecules with significant chemical potential and relatively unexplored photophysical properties. We combined femtosecond broadband fluorescence up-conversion and fs broadband Vis-pump Vis-probe spectroscopy to comprehensively characterize the photoreaction of 5,10,15-tris-pentafluorophenyl-corrolato-antimony(V-trans-difluoride (Sb-tpfc-F2. Upon fs Soret band excitation at ~400 nm, the energy relaxed almost completely to Q band electronic excited states with a time constant of 500 ± 100 fs; this is evident from the decay of Soret band fluorescence at around 430 nm and the rise time of Q band fluorescence, as well as from Q band stimulated emission signals at 600 and 650 nm with the same time constant. Relaxation processes on a time scale of 10 and 20 ps were observed in the fluorescence and absorption signals. Triplet formation showed a time constant of 400 ps, with an intersystem crossing yield from the Q band to the triplet manifold of between 95% and 99%. This efficient triplet formation is due to the spin-orbit coupling of the antimony ion.

  14. Assessment of Corneal Biomechanical Properties by CorVis ST in Patients with Dry Eye and in Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Qin Long

    2015-01-01

    Full Text Available Purpose. To investigate corneal biomechanical properties in patients with dry eye and in healthy subjects using Corneal Visualization Scheimpflug Technology (CorVis ST. Methods. Biomechanical parameters were measured using CorVis ST in 28 eyes of 28 patients with dry eye (dry eye group and 26 normal subjects (control group. The Schirmer I test value, tear film break-up time (TBUT, and corneal staining score (CSS were recorded for each eye. Biomechanical properties were compared between the two groups and bivariate correlation analysis was used to assess the relationship between biomechanical parameters and dry eye signs. Results. Only one of the ten biomechanical parameters was significantly different between the two groups. Patients in the dry eye group had significantly lower highest concavity time (HC-time (P=0.02 than the control group. Correlation analysis showed a significant negative correlation between HC-time and CSS with marginal P value (ρ=-0.39, P=0.04 in the dry eye group. Conclusions. The corneal biomechanical parameter of HC-time is reduced in dry eyes compared to normal eyes. There was also a very weak but significant negative correlation between HC-time and CSS in the dry eye group, indicating that ocular surface damage can give rise to a more compliant cornea in dry eyes.

  15. Development of an Age Band on the ManuVis for 3-Year-Old Children with Visual Impairments.

    Science.gov (United States)

    Reimer, A M; Barsingerhorn, A D; Overvelde, A; Nijhuis-Van der Sanden, M W G; Boonstra, F N; Cox, R F A

    2017-08-01

    To compare fine motor performance of 3-year-old children with visual impairment with peers having normal vision, to provide reference scores for 3-year-old children with visual impairment on the ManuVis, and to assess inter-rater reliability. 26 children with visual impairment (mean age: 3 years 7 months (SD 3 months); 17 boys) and 28 children with normal vision (mean age: 3 years 7 months (SD 4 months); 14 boys) participated in the study. The ManuVis age band for 3-year-old children comprised two one-handed tasks, two two-handed tasks, and a pre-writing task. Children with visual impairment needed more time on all tasks (p children with normal vision (p Children aged 42-47 months performed significantly faster on two tasks and had better total scores than children aged 36-41 months (p children is appropriate to assess fine motor skills, and is sensitive to differences between children with visual impairment and normal vision and between half-year age groups. Reference scores are provided for 3-year-old children with visual impairment to identify delayed fine motor development.

  16. Growth of block copolymer stabilized metal nanoparticles probed simultaneously by in situ XAS and UV-Vis spectroscopy.

    Science.gov (United States)

    Nayak, C; Bhattacharyya, D; Jha, S N; Sahoo, N K

    2016-01-01

    The growth of Au and Pt nanoparticles from their respective chloride precursors using block copolymer-based reducers has been studied by simultaneous in situ measurement of XAS and UV-Vis spectroscopy at the energy-dispersive EXAFS beamline (BL-08) at INDUS-2 SRS at RRCAT, Indore, India. While the XANES spectra of the precursor give real-time information on the reduction process, the EXAFS spectra reveal the structure of the clusters formed at the intermediate stages of growth. The growth kinetics of both types of nanoparticles are found to be almost similar and are found to follow three stages, though the first stage of nucleation takes place earlier in the case of Au than in the case of Pt nanoparticles due to the difference in the reduction potential of the respective precursors. The first two stages of the growth of Au and Pt nanoparticles as obtained by in situ XAS measurements could be corroborated by simultaneous in situ measurement of UV-Vis spectroscopy also.

  17. Interaction between a cationic porphyrin and ctDNA investigated by SPR, CV and UV-vis spectroscopy.

    Science.gov (United States)

    Xu, Zi-Qiang; Zhou, Bo; Jiang, Feng-Lei; Dai, Jie; Liu, Yi

    2013-10-01

    The interaction between ctDNA and a cationic porphyrin was studied in this work. The binding process was monitored by surface plasmon resonance (SPR) spectroscopy in detail. The association, dissociation rate constants and the binding constants calculated by global analysis were 2.4×10(2)±26.4M(-1)s(-1), 0.011±0.0000056s(-1) and 2.18×10(4)M(-1), respectively. And the results were confirmed by cyclic voltammetry and UV-vis absorption spectroscopy. The binding constants obtained from cyclic voltammetry and UV-vis absorption spectroscopy were 8.28×10(4)M(-1) and 6.73×10(4)M(-1) at 298K, respectively. The covalent immobilization methodology of ctDNA onto gold surface modified with three different compounds was also investigated by SPR. These compounds all contain sulfydryl but with different terminated functional groups. The results indicated that the 11-MUA (HS(CH2)10COOH)-modified gold film is more suitable for studying the DNA-drug interaction. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Investigation of Antioxidant Activity of Pomegranate Juices by Means of Electron Paramagnetic Resonance and UV-Vis Spectroscopy.

    Science.gov (United States)

    Kozik, Violetta; Jarzembek, Krystyna; Jędrzejowska, Agnieszka; Bąk, Andrzej; Polak, Justyna; Bartoszek, Mariola; Pytlakowska, Katarzyna

    2015-01-01

    Pomegranate fruit (Punica granatum L.) is a source of numerous phenolic compounds, and it contains flavonoids such as anthocyanins, anthocyanidins, cyanidins, catechins and other complexes of flavonoids, ellagitannins, and hydrolyzed tannins. Pomegranate juice shows antioxidant, antiproliferative, and anti-atherosclerotic properties. The antioxidant capacity (TEAC) of the pomegranate juices was measured using electron paramagnetic resonance (EPR) spectroscopy and 1,1-diphenyl-2-picrylhydrazyl (DPPH•) as a source of free radicals, and the total phenolic (TP) content was measured using UV-Vis spectroscopy. All the examined pomegranate juices exhibited relatively high antioxidant properties. The TEAC values determined by means of EPR spectroscopy using Trolox (TE) as a free radical scavenger were in the range of 463.12 to 1911.91 μmol TE/100 mL juice. The TP content measured by the Folin-Ciocalteu method, using gallic acid (GA) as a free radical scavenger, widely varied in the investigated pomegranate juice samples and ranged from 1673.62 to 5263.87 mg GA/1 L juice. The strongest antioxidant properties were observed with the fresh pomegranate juices obtained from the fruits originating from Israel, Lebanon, and Azerbaijan. Correlation analysis of numerical data obtained by means of EPR spectroscopy (TEAC) and UV-Vis spectroscopy (TP) gave correlation coefficient (r)=0.90 and determination coefficient (r2)=0.81 (P<0.05).

  19. Interactions of the baicalin and baicalein with bilayer lipid membranes investigated by cyclic voltammetry and UV-Vis spectroscopy.

    Science.gov (United States)

    Zhang, Ying; Wang, Xuejing; Wang, Lei; Yu, Miao; Han, Xiaojun

    2014-02-01

    The baicalin and baicalein are the major flavonoids found in Radix Scutellariae, an essential herb in traditional Chinese medicine for thousands of years. The interactions of the baicalin and baicalein with lipid bilayer membranes were studied using cyclic voltammetry and UV-Vis spectroscopy. The thickness d of supported bilayer lipid membranes was calculated as d=4.59(±0.36) nm using AC impedance spectroscopy. The baicalein interacted with egg PC bilayer membranes in a dose-dependent manner. The responses of K3Fe(CN)6 on lipid bilayer membrane modified Pt electrode linearly increased in a concentration range of baicalein from 6.25μM to 25μM with a detection limit of 0.1μM and current-concentration sensitivity of 0.11(±0.01) μA/μM, and then reached a plateau from 25μM to 50μM. However the baicalin showed much weaker interactions with egg PC bilayer membranes. UV-Vis spectroscopy also confirmed that the baicalein could interact with egg PC membranes noticeably, but the interaction of baicalin with membranes was hard to be detected. The results provide useful information on understanding the mechanism of action of Radix Scutellariae in vivo. © 2013.

  20. Probing the behaviors of gold nanorods in metastatic breast cancer cells based on UV-vis-NIR absorption spectroscopy.

    Science.gov (United States)

    Zhang, Weiqi; Ji, Yinglu; Meng, Jie; Wu, Xiaochun; Xu, Haiyan

    2012-01-01

    In this work, behaviors of positively-charged AuNRs in a highly metastatic tumor cell line MDA-MB-231 are examined based on UV-vis-NIR absorption spectroscopy in combination with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy (TEM) and dark-field microscopic observation. It is found that characteristic surface plasmon resonance (SPR) peaks of AuNRs can be detected using spectroscopic method within living cells that have taken up AuNRs. The peak area of transverse SPR band is shown to be proportionally related to the amount of AuNRs in the cells determined with ICP-MS, which suggests a facile and real time quantification method for AuNRs in living cells. The shape of longitudinal SPR band in UV-vis-NIR spectrum reflects the aggregation state of AuNRs in the cells during the incubation period, which is proved by TEM and microscopic observations. Experimental results reveal that AuNRs are internalized by the cells rapidly; the accumulation, distribution and aggregation of AuNRs in the cells compartments are time and dose dependent. The established spectroscopic analysis method can not only monitor the behaviors of AuNRs in living cells but may also be helpful in choosing the optimum laser stimulation wavelength for anti-tumor thermotherapy.

  1. [UV-vis spectrometric characterization of the composition of active complex in the Ni-P plating solution].

    Science.gov (United States)

    Xu-cheng, Wang; Wen-bin, Cai; Wei-jiang, Wang

    2004-07-01

    A strong complex agent is normally used in the alkaline chemical plating solution for Ni-P plating in order to prevent Ni ion from precipitation by hydrolysis. To keep a stable pH condition, an NH3-NH4Cl buffer system is used. Traditionally, it is considered that NH3 does not participate in the complex because of the relatively low Ni-NH3 complexing constant, but some experimental results cannot be explained reasonably. Touhami etc. have proposed a ternary Ni-citrate-NH3 complex involved in the discharge process, however they cannot give the direct support on the presence of this complex in solution. In this paper, a UV-Vis spectrometric study was carried out to identify the nickel complex in the Ni-P plating solution, and the results indicated the presence of both Ni-cit binary complex and Ni-cit-ammonia ternary complex. After the systematic investigation of the dependence of UV-Vis spectra on the two ligands (cit and ammonia), the composition of this Ni-cit-ammonia ternary complex was supposed to be Ni(II)(C6H5O(7)3-)(NH3)3.

  2. TiO{sub 2}/WO{sub 3} photoactive bilayers in the UV-Vis light region

    Energy Technology Data Exchange (ETDEWEB)

    Vasilaki, E. [University of Crete, Department of Chemistry, Heraklion, Crete (Greece); Technological Educational Institute of Crete, Center of Materials Technology and Photonics, School of Engineering, Heraklion, Crete (Greece); Vernardou, D. [Technological Educational Institute of Crete, Center of Materials Technology and Photonics, School of Engineering, Heraklion, Crete (Greece); Kenanakis, G.; Katsarakis, N. [Technological Educational Institute of Crete, Center of Materials Technology and Photonics, School of Engineering, Heraklion, Crete (Greece); Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, Vassilika Vouton, P.O. Box 1385, Heraklion, Crete (Greece); Vamvakaki, M. [Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, Vassilika Vouton, P.O. Box 1385, Heraklion, Crete (Greece); University of Crete, Department of Materials Science and Technology, Heraklion, Crete (Greece)

    2017-04-15

    In this work, photoactive bilayered films consisting of anatase TiO{sub 2} and monoclinic WO{sub 3} were synthesized by a sol-gel route. Titanium isopropoxide and tungsten hexachloride were used as metal precursors and deposition was achieved by spin-coating on Corning glass substrates. The samples were characterized by X-ray diffraction, photoluminescence, UV-Vis, and Raman spectroscopy, as well as field emission scanning electron microscopy. The prepared immobilized catalysts were tested for their photocatalytic performance by the decolorization of methylene blue in aqueous matrices, under UV-Vis light irradiation. The annealing process influenced the crystallinity of the bilayered films, while the concentration of the tungsten precursor solution and the position of the tungsten trioxide layer further affected their photocatalytic performance. In particular, the photocatalytic performance of the bilayered films was optimized at a concentration of 0.1 M of the WO{sub 3} precursor solution, when deposited as an overlying layer on TiO{sub 2} by two annealing steps (∝76% methylene blue decolorization in 300 min of irradiation versus ∝59% in the case of a bare TiO{sub 2} film). In general, the coupled layer catalysts exhibited superior photoactivity compared to that of bare TiO{sub 2} films with WO{sub 3} acting as an electron trap, resulting, therefore, in a more efficient electron-hole separation and inhibiting their recombination. (orig.)

  3. Luminescence of Er3+ doped double lead halide crystals under X-ray, UV, VIS and IR excitation

    Science.gov (United States)

    Serazetdinov, A. R.; Smirnov, A. A.; Pustovarov, V. A.; Isaenko, L. I.

    2017-09-01

    Er3+ doped double lead halide crystals incorporate a number of properties making them interesting for practical use in light conducting materials. X-ray excited luminescence (XRL) spectra, photoluminescence (PL) spectra in region of 1.5-3.5 eV, photoluminescence excitation (PLE) spectra (2.75-5 eV) and anti-stokes luminescence (ASL) spectra were measured at room temperature in KPb2Cl5 (KPC) and RbPb2Br5 (RPB) matrices doped with Er3+ (1%) ions and in KPC doped with Er3++ Yb3+ ions(1:3 ratio concentration). Intraconfigurational f→f transitions are observed in Er3+ ions in most of the cases. The concrete spectrum form is strongly dependent on the excitation energy. Under 980 nm excitation upper Er3+ levels are excited, showing upconversional processes. In case of 313 nm (UV) and 365 nm (VIS) excitation self trapped exciton luminescence was detected in RPB crystal. Additional Yb3+ doping ions strongly increase quantum yield under 980 nm excitation and this doping cause insignificant influence on quantum yield under VIS or UV excitation.

  4. Structure and UV-vis spectrum of C(60) fullerene in ethanol: a sequential molecular dynamics/quantum mechanics study.

    Science.gov (United States)

    Malaspina, Thaciana; Fileti, Eudes E; Rivelino, Roberto

    2007-10-18

    A molecular dynamics simulation combined with semiempirical quantum mechanics calculations has been performed to investigate the structure, dynamical, and electronic properties of pure C60 in liquid ethanol. The behavior of the fullerene alcoholic solution was obtained by using the NPT ensemble under ambient conditions, including one C60 fullerene immersed in 1000 ethanol molecules. Our analyzed center-of-mass pairwise radial distribution function indicated that, on average, there are 32, 72, 132, and 187 ethanol molecules around, respectively, the first, second, third, and fourth solvation shells of the C60 molecule. To investigate the UV-vis transition energies of C60 in the presence of ethanol, we have considered constituents of the time uncorrelated supramolecular structures of the first solvation shell, i.e., clusters of C60@{EtOH}32 types. The semiempirical calculations were performed at the intermediate neglect of differential overlap level with configuration interaction singles (INDO/CIS). Our results have pointed out that the characteristic C60 UV-vis absorbance peaks are slightly shifted to longer wavelengths, as compared to the isolated molecule. These findings are in connection with the weak donor-acceptor character of the interactions involving electron lone pairs of oxygen atoms on the solvent and the fullerene surface.

  5. BasinVis 1.0: A MATLAB®-based program for sedimentary basin subsidence analysis and visualization

    Science.gov (United States)

    Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

    2016-06-01

    Stratigraphic and structural mapping is important to understand the internal structure of sedimentary basins. Subsidence analysis provides significant insights for basin evolution. We designed a new software package to process and visualize stratigraphic setting and subsidence evolution of sedimentary basins from well data. BasinVis 1.0 is implemented in MATLAB®, a multi-paradigm numerical computing environment, and employs two numerical methods: interpolation and subsidence analysis. Five different interpolation methods (linear, natural, cubic spline, Kriging, and thin-plate spline) are provided in this program for surface modeling. The subsidence analysis consists of decompaction and backstripping techniques. BasinVis 1.0 incorporates five main processing steps; (1) setup (study area and stratigraphic units), (2) loading well data, (3) stratigraphic setting visualization, (4) subsidence parameter input, and (5) subsidence analysis and visualization. For in-depth analysis, our software provides cross-section and dip-slip fault backstripping tools. The graphical user interface guides users through the workflow and provides tools to analyze and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the results using the full range of available plot options in MATLAB. We demonstrate all functions in a case study of Miocene sediment in the central Vienna Basin.

  6. Integrated field testing of planetary robotics vision processing: the PRoVisG campaign in Tenerife 2011

    Science.gov (United States)

    Paar, G.; Waugh, L.; Barnes, D. P.; Pajdla, T.; Woods, M.; Graf, H.-R.; Gao, Y.; Willner, K.; Muller, J.-P.; Li, R.

    2012-01-01

    In order to maximize the use of a robotic probe during its limited lifetime, scientists immediately have to be provided the best achievable visual quality of 3D data products. The EU FP7-SPACE Project PRoVisG (2008-2012) develops technology for the rapid processing and effective representation of visual data by improving ground processing facilities. In September 2011 PRoVisG held a Field Trials campaign in the Caldera of Tenerife to verify the implemented 3D Vision processing mechanisms and to collect various sets of reference data in representative environment. The campaign was strongly supported by the Astrium UK Rover Bridget as a representative platform which allows simultaneous onboard mounting and powering of various vision sensors such as the Aberystwyth ExoMars PanCam Emulator (AUPE). The paper covers the preparation work for such a campaign and highlights the experiments that include standard operations- and science- related components but also data capture to verify specific processing functions. We give an overview of the captured data and the compiled and envisaged processing results, as well as a summary of the test sites, logistics and test assets utilized during the campaign.

  7. Internet vis-a-vis marine biology

    Digital Repository Service at National Institute of Oceanography (India)

    Chavan, V.S.

    stream_size 6 stream_content_type text/plain stream_name Indian_J_Mar_Sci_27_463.pdf.txt stream_source_info Indian_J_Mar_Sci_27_463.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  8. Application of Time-Dependent Density Functional and Natural Bond Orbital Theories to the UV-vis Absorption Spectra of Some Phenolic Compounds.

    Science.gov (United States)

    Marković, Svetlana; Tošović, Jelena

    2015-09-03

    The UV-vis properties of 22 natural phenolic compounds, comprising anthraquinones, neoflavonoids, and flavonoids were systematically examined. The time-dependent density functional theory (TDDFT) approach in combination with the B3LYP, B3LYP-D2, B3P86, and M06-2X functionals was used to simulate the UV-vis spectra of the investigated compounds. It was shown that all methods exhibit very good (B3LYP slightly better) performance in reproducing the examined UV-vis spectra. However, the shapes of the Kohn-Sham molecular orbitals (MOs) involved in electronic transitions were misleading in constructing the MO correlation diagrams. To provide better understanding of redistribution of electron density upon excitation, the natural bond orbital (NBO) analysis was applied. Bearing in mind the spatial and energetic separations, as well as the character of the π bonding, lone pair, and π* antibonding natural localized molecular orbitals (NLMOs), the "NLMO clusters" were constructed. NLMO cluster should be understood as a part of a molecule characterized with distinguished electron density. It was shown that all absorption bands including all electronic transitions need to be inspected to fully understand the UV-vis spectrum of a certain compound, and, thus, to learn more about its UV-vis light absorption. Our investigation showed that the TDDFT and NBO theories are complementary, as the results from the two approaches can be combined to interpret the UV-vis spectra. Agreement between the predictions of the TDDFT approach and those based on the NLMO clusters is excellent in the case of major electronic transitions and long wavelengths. It should be emphasized that the approach for investigation of UV-vis light absorption based on the NLMO clusters is applied for the first time.

  9. Using UHPLC and UV-vis Fingerprint Method to Evaluate Substitutes for Swertia mileensis: An Endangered Medicinal Plant

    Science.gov (United States)

    Li, Jie; Zhang, Ji; Jin, Hang; Wang, Yuan-Zhong; Huang, Heng-Yu

    2017-01-01

    Background: Millions of people are killed by viral hepatitis every year in the world, whereas many relevant medicines are too expensive to purchase. Swertia mileensis, a medicinal plant for hepatitis in the system of traditional Chinese medicine, has been vanishing gradually because of overexploitation. Objective: To find substitutes of S. mileensis and reduce the cost of purchasing drugs for hepatitis patients, the similarity of phytochemical constituents between S. mileensis and other three Swertia species was compared. Materials and Methods: Both ultra high performance liquid chromatographies and ultraviolet-vis fingerprints of four Swertia species were developed. Methanol extracts of the stems and leaves were used as samples to establish the fingerprint. The calibration curve was drawn for quantitative analysis of swertiamarin. The data of ultra high performance liquid chromatographies were evaluated statistically using similarity analysis and principal component analysis. Results: The result shows a significant difference at area of 204–290 nm in the ultraviolet fingerprint. Swertiamarin, the only one common peak, was defined in chromatographic fingerprints of four Swertia species. The quantitative analysis suggested that the highest concentration of swertiamarin is in S. davidii. The similarity indexes between different samples were almost under 0.60. In the principal component analysis, separate points not only represent the distinction among different species, but also perform chemical discrepancies in content between stems and leaves of one same species. Conclusions: S. angustifolia, S. davidii, and S. punicea are not suitable as substitutes of S. mileensis because of their remarkable differences in entirety and local part. In order to address issues about substitutes and high cost of purchasing drugs, more studies need to undertake. SUMMARY The UHPLC fingerprint method indicated the significant difference on chemical ingredients in four plants from

  10. Interaction between morin and AOT reversed micelles--studies with UV-vis at 25 °C.

    Science.gov (United States)

    Bhattarai, Ajaya; Wilczura-Wachnik, H

    2014-01-30

    The precise measurements of morin absorbance in presence of surfactant/solvent/water systems at 25 °C by UV-vis technique are reported. The surfactant used in presented study was sodium bis(2-ethylhexyl) sulfosuccinate called Aerosol-OT or AOT. The solvents selected were: ethanol, ethylene glycol, and n-decanol. The concentrations of AOT were varied between 0.001 and 0.4 mol/kg. Morin concentration in quvette during UV-vis registration was not equals in all solvent because of its different solubility and absorption intensity depending on the solvent. Water concentration in the studied systems was defined by R parameter according to relation: R=[H2O]/[AOT] and was equal 0, 30 and 40 in ethanol; 0, 10, 20 and 30 in ethylene glycol and 0, 10, 20, 30, and 40 in n-decanol. In presented work a Nernstian distribution of morin between the organic and micellar phases was assumed. The intensity of morin absorbance as a function of AOT concentration was analyzed. Using Non-linear Regression Procedure (NLREG) morin binding constant (K' [mol/kg]), and morin distribution constant (K) between organic phase and AOT micellar phase have been calculated. The experimental results have shown a significant influence of solvent, surfactant and water presence on morin UV-vis spectrum. Calculated data pointed out on different transfer of morin molecules from the organic to micellar phase depending on the solvent. Moreover, results of calculations indicate on competition between morin and water molecules interacting with AOT polar heads. Morin molecules privileged location in AOT reversed micelles strongly depends on the solvent. In case of systems with ethylene glycol as solvent is possible morin molecules location in polar cores of AOT reversed micelles as results of strong interaction between AOT polar heads and morin hydroxyl groups, whereas in case of ethanol and n-decanol morin molecules are located in palisade layer. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Compositional and surface characterization of HULIS by UV-Vis, FTIR, NMR and XPS: Wintertime study in Northern India

    Science.gov (United States)

    Kumar, Varun; Goel, Anubha; Rajput, Prashant

    2017-09-01

    This study (first attempt) characterizes HULIS (Humic Like Substances) in wintertime aerosols (n = 12 during day and nighttime each) from Indo-Gangetic Plain (IGP, at Kanpur) by using various state-of-the art techniques such as UV-VIS, FTIR, 1H NMR and XPS. Based on UV-Vis analysis the absorption coefficient at 365 nm (babs-365) of HULIS was found to average at 13.6 and 28.8 Mm-1 during day and nighttime, respectively. Relatively high babs-365 of HULIS during the nighttime is attributed to influence of fog-processing. However, the power fit of UV-Vis spectrum provided near similar AAE (absorption Angstrom exponent) value of HULIS centering at 4.9 ± 1.4 and 5.1 ± 1.3 during daytime and nighttime, respectively. FTIR spectra and its double derivative revealed the presence of various functional groups viz. alcohols, ketones aldehydes, carboxylic acids as well as unsaturated and saturated carbon bonds. 1H NMR spectroscopy was applied to quantify relative percentage of various types of hydrogen atoms contained in HULIS, whereas XPS technique provided information on surface composition and oxidation states of various elements present. A significantly high abundance of H‒C‒O group has been observed in HULIS (based on 1H NMR); 41.4± 2.7% and 30.9± 2.4% in day and nighttime, respectively. However, aromatic protons (Ar-H) were higher in nighttime samples (19.3± 1.8%) as compared to that in daytime samples (7.5 ± 1.9). XPS studies revealed presence of various species on the surface of HULIS samples. Carbon existed in 7 different chemical states while total nitrogen and sulfur exhibited 3 and 2 different oxidation states (respectively) on the surface of HULIS. This study reports structural information and absorption properties of HULIS which has implications to their role as cloud condensation nuclei and atmospheric direct radiative forcing.

  12. Vibrational effects on UV/Vis laser-driven π-electron ring currents in aromatic ring molecules

    Science.gov (United States)

    Mineo, H.; Lin, S. H.; Fujimura, Y.

    2014-10-01

    We present the results of a theoretical study of vibrational effects on UV/Vis laser-driven π-electron ring currents in aromatic ring molecules. We consider vibrational effects on both coherent and non-coherent (single quantum state) ring currents. The coherent ring current originates from an excitation of a pair of quasi-degenerate electronic states by an ultrashort linearly polarized UV/Vis laser pulse, while the non-coherent ring current originates from by an excitation of a degenerated electronic state of an aromatic ring molecule with high symmetry by a circularly polarized electric field of a UV/Vis laser pulse. The magnitude of a generated ring current can be expressed as an average of those of the bond currents for both the coherent and non-coherent cases. We derive an analytical expression for the magnitude of the bond currents in the adiabatic approximation. Using the expression, we performed calculations of a non-coherent ring current generated in the optically allowed excited state (1E1U) of benzene and the time evolution of coherent ring current of (P)-2,2-biphenol. Vibrational effects on the non-coherent ring current of benzene were found to be negligibly small. We paid particular attention to the vibrational effects induced by the torsion mode on time evolution of the coherent ring current along the bond bridging between the two aromatic rings of (P)-2,2-biphenol. By comparing the time evolution of the coherent ring current with that in the frozen-nuclear approximation, we found that inclusion of the low-frequency torsion mode brings about modulations in the beating in the ring current. The modulations in the time evolution of the coherent ring current were brought about by contribution of several pairs of the coherently excited vibronic states. Coherent vibronic ring currents generated from pairs of the coherently excited vibronic states interfere each other. The existence of the pairs originates from relatively large potential displacement of the

  13. Chemical composition and surfactant characteristics of marine foams investigated by means of UV-vis, FTIR and FTNIR spectroscopy.

    Science.gov (United States)

    Mecozzi, Mauro; Pietroletti, Marco

    2016-11-01

    In this study, we collected the ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR) and Fourier transform near-infrared (FTNIR) spectra of marine foams from different sites and foams produced by marine living organisms (i.e. algae and molluscs) to retrieve information about their molecular and structural composition. UV-vis spectra gave information concerning the lipid and pigment contents of foams. FTIR spectroscopy gave a more detailed qualitative information regarding carbohydrates, lipids and proteins in addition with information about the mineral contents of foams. FTNIR spectra confirmed the presence of carbohydrates, lipids and proteins in foams. Then, due to the higher content of structural information of FTIR spectroscopy with respect to FTNIR and UV-vis, we join the FTIR spectra of marine foams to those of humic substance from marine sediments and to the spectra of foams obtained by living organisms. We submitted this resulting FTIR spectral dataset to statistical multivariate methods to investigate specific aspects of foams such as structural similarity among foams and in addition, contributions from the organic matter of living organisms. Cluster analysis (CA) evidenced several cases (i.e. clusters) of marine foams having high structural similarity with foams from vegetal and animal samples and with humic substance extracted from sediments. These results suggested that all the living organisms of the marine environment can give contributions to the chemical composition of foams. Moreover, as CA also evidenced cases of structural differences within foam samples, we applied two-dimensional correlation analysis (2DCORR) to the FTIR spectra of marine foams to investigate the molecular characteristics which caused these structural differences. Asynchronous spectra of two-dimensional correlation analysis showed that the structural heterogeneity among foam samples depended reasonably on the presence and on the qualitative difference of

  14. A portable nondestructive detection device of quality and nutritional parameters of meat using Vis/NIR spectroscopy

    Science.gov (United States)

    Wang, Wenxiu; Peng, Yankun; Wang, Fan; Sun, Hongwei

    2017-05-01

    The improvement of living standards has urged consumers to pay more attention to the quality and nutrition of meat, so the development of nondestructive detection device for quality and nutritional parameters is commercioganic undoubtedly. In this research, a portable device equipped with visible (Vis) and near-infrared (NIR) spectrometers, tungsten halogen lamp, optical fiber, ring light guide and embedded computer was developed to realize simultaneous and fast detection of color (L*, a*, b*), pH, total volatile basic nitrogen (TVB-N), intramuscular fat (IF), protein and water content in pork. The wavelengths of dual-band spectrometers were 400 1100 nm and 940 1650 nm respectively and the tungsten halogen lamp cooperated with ring light guide to form a ring light source and provide appropriate illumination intensity for sample. Software was self-developed to control the functionality of dual-band spectrometers, set spectrometer parameters, acquire and process Vis/NIR spectroscopy and display the prediction results in real time. In order to obtain a robust and accurate prediction model, fresh longissimus dorsi meat was bought and placed in the refrigerator for 12 days to get pork samples with different freshness degrees. Besides, pork meat from three different parts including longissimus dorsi, haunch and lean meat was collected for the determination of IF, protein and water to make the reference values have a wider distribution range. After acquisition of Vis/NIR spectra, data from 400 1100 nm were pretreated with Savitzky-Golay (S-G) filter and standard normal variables transform (SNVT) and spectrum data from 940 1650 nm were preprocessed with SNVT. The anomalous were eliminated by Monte Carlo method based on model cluster analysis and then partial least square regression (PLSR) models based on single band (400 1100 nm or 940 1650 nm) and dual-band were established and compared. The results showed the optimal models for each parameter were built with correlation

  15. Discrimination of Brazilian propolis according to the seasoning using chemometrics and machine learning based on UV-Vis scanning data.

    Science.gov (United States)

    Tomazzoli, Maíra Maciel; Pai Neto, Remi Dal; Moresco, Rodolfo; Westphal, Larissa; Zeggio, Amélia Regina Somensi; Specht, Leandro; Costa, Christopher; Rocha, Miguel; Maraschin, Marcelo

    2015-10-21

    Propolis is a chemically complex biomass produced by honeybees (Apis mellifera) from plant resins added of salivary enzymes, beeswax, and pollen. The biological activities described for propolis were also identified for donor plant's resin, but a big challenge for the standardization of the chemical composition and biological effects of propolis remains on a better understanding of the influence of seasonality on the chemical constituents of that raw material. Since propolis quality depends, among other variables, on the local flora which is strongly influenced by (a)biotic factors over the seasons, to unravel the harvest season effect on the propolis' chemical profile is an issue of recognized importance. For that, fast, cheap, and robust analytical techniques seem to be the best choice for large scale quality control processes in the most demanding markets, e.g., human health applications. For that, UV-Visible (UV-Vis) scanning spectrophotometry of hydroalcoholic extracts (HE) of seventy-three propolis samples, collected over the seasons in 2014 (summer, spring, autumn, and winter) and 2015 (summer and autumn) in Southern Brazil was adopted. Further machine learning and chemometrics techniques were applied to the UV-Vis dataset aiming to gain insights as to the seasonality effect on the claimed chemical heterogeneity of propolis samples determined by changes in the flora of the geographic region under study. Descriptive and classification models were built following a chemometric approach, i.e. principal component analysis (PCA) and hierarchical clustering analysis (HCA) supported by scripts written in the R language. The UV-Vis profiles associated with chemometric analysis allowed identifying a typical pattern in propolis samples collected in the summer. Importantly, the discrimination based on PCA could be improved by using the dataset of the fingerprint region of phenolic compounds (λ = 280-400ηm), suggesting that besides the biological activities of those

  16. Formic acid enhanced effective degradation of methyl orange dye in aqueous solutions under UV-Vis irradiation.

    Science.gov (United States)

    Wang, Jingjing; Bai, Renbi

    2016-09-15

    Developing efficient technologies to treat recalcitrant organic dye wastewater has long been of great research and practical interest. In this study, a small molecule, formic acid (FA), was applied as a process enhancer for the degradation of methyl orange (MO) dye as a model recalcitrant organic pollutant in aqueous solutions under the condition of UV-Vis light irradiation and air aeration at the ambient temperature of 25 °C. It was found that the decolouration of the dye solutions can be rapidly achieved, reducing the time, for example, from around 17.6 h without FA to mostly about less than 2 h with the presence of FA. The mineralization rate of MO dye reached as high as 81.8% in 1.5 h in the case of initial MO dye concentration at 25 mg L(-1), which is in contrast to nearly no mineralization of the MO dye for a similar system without the FA added. The study revealed that the generation of the H2O2 species in the system was enhanced and the produced OH radicals effectively contributed to the degradation of the MO dye. Process parameters such as the initial concentration of MO dye, FA dosage and solution pH were all found to have some effect on the degradation efficiency under the same condition of UV-Vis light irradiation and air aeration. The MO dye degradation performance was found to follow a first-order reaction rate to the MO dye concentration in most cases and there existed a positive correlation between the reaction rate constant and the initial FA concentration. Compared to the traditional H2O2/UV-Vis oxidation system, the use of FA as a process-enhancing agent can have the advantages of low cost, easy availability, and safe to use. The study hence demonstrates a promising approach to use a readily available small molecule of FA to enhance the degradation of recalcitrant organic pollutants, such as MO dye, especially for their pre-treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Frentes de ondas (wavefronts e limites da visão humana Parte 2: aplicações

    Directory of Open Access Journals (Sweden)

    Jankov Mirko

    2002-01-01

    Full Text Available Os valores médios de todos os coeficientes de Zernike são de aproximadamente zero, ao passo que a variabilidade individual é muito grande, o que significa que os seres humanos, como espécie em geral, têm sistema óptico muito bom, mas individualmente imperfeito. Certa instabilidade temporal das aberrações de alta ordem foi descrita em função da acomodação. Este fato leva a uma nova pergunta: a correção de todas as aberrações para visão em estado não acomodado será benéfica para visão de perto também? É possível modificar e diminuir as aberrações ópticas por meio de foto-ablação por "scanning spot LASER" tendo os dados das frentes de ondas como a base para perfil de ablação individualizado. É fundamental a fixação perfeita do feixe de "LASER" em relação ao olho, obtida com os "eye-trackers" de alta freqüência. O benefício visual teórico da correção das aberrações de alta ordem seria de até 12 vezes. A meta principal dos tratamentos guiados pelas frentes de onda é de não permitir a piora da visão depois do tratamento cirúrgico refrativo, como pode ocorrer hoje em dia com os tratamentos tradicionais a "LASER"; em seguida, a meta se es-tenderia aos melhoramentos visuais, bem como ao tratamento dos casos de córneas extremamente irregulares (ablações primárias irregulares, pequenas ou descentradas, a presença das ilhas centrais ou irregularidades após transplante de córnea. O entendimento da terminologia e das bases da nova evolução tecnológica, bem como o constante acompanhamento crítico dos resultados publicados é fundamental para a abordagem moderna dos problemas relativos à refração e à cirurgia refrativa.

  18. Tantalum (oxy)nitrides nanotube arrays for the degradation of atrazine in vis-Fenton-like process

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingxun, E-mail: yxdu@niglas.ac.cn [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China); Zhao, Lu [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China); Chang, Yuguang [School of Biochemical and Environmental Engineering, Nanjing Xiaozhuang Univeristy, Nanjing 211171 (China); Su, Yaling [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China)

    2012-07-30

    Highlights: Black-Right-Pointing-Pointer Tantala nanotubes on a Ta foil were formed by anodization in a NH{sub 4}F-containing electrolyte. Black-Right-Pointing-Pointer Tantalum (oxy)nitrides nanotubes were active for Fe{sup 3+} reduction under visible light. Black-Right-Pointing-Pointer Atrazine degradation by {center_dot}OH was accelerated with tantalum (oxy)nitrides nanotubes. Black-Right-Pointing-Pointer Tantalum (oxy)nitrides nanotubes display stable performance for atrazine degradation. - Abstract: In order to overcome the limitation of the application of nanoparticles, tantalum (oxy)nitrides nanotube arrays on a Ta foil were synthesized and introduced in vis (visible light)-Fenton-like system to enhance the degradation of atrazine. At first, the anodization of tantalum foil in a mild electrolyte solution containing ethylene glycol and water (v:v = 2:1) plus 0.5 wt.% NH{sub 4}F produced tantala nanotubes with an average diameter of 30 nm and a length of approximately 1 {mu}m. Then the nitridation of tantala nanotube arrays resulted in the replacement of N atoms to O atoms to form tantalum (oxy)nitrides (TaON and Ta{sub 3}N{sub 5}), as testified by XRD and XPS analyses. The synthesized tantalum (oxy)nitrides nanotubes absorb well in the visible region up to 600 nm. Under visible light, tantalum (oxy)nitrides nanotube arrays were catalytically active for Fe{sup 3+} reduction. With tantalum (oxy)nitrides nanotube arrays, the degradation of atrazine and the formation of the intermediates in vis/Fe{sup 3+}/H{sub 2}O{sub 2} system were significantly accelerated. This was explained by the higher concentration of Fe{sup 2+} and thus the faster decomposition of H{sub 2}O{sub 2} with tantalum (oxy)nitrides nanotubes. In addition, tantalum (oxy)nitrides nanotubes exhibited stable performance during atrazine degradation for three runs. The good performance and stability of the tantalum (oxy)nitrides nanotubes film with the convenient separation, suggest that this film is

  19. Ultraviolet-Visible (UV-Vis) Microspectroscopic System Designed for the In Situ Characterization of the Dehydrogenation Reaction Over Platinum Supported Catalytic Microchannel Reactor.

    Science.gov (United States)

    Suarnaba, Emee Grace Tabares; Lee, Yi Fuan; Yamada, Hiroshi; Tagawa, Tomohiko

    2016-11-01

    An ultraviolet visible (UV-Vis) microspectroscopic system was designed for the in situ characterization of the activity of the silica supported platinum (Pt) catalyst toward the dehydrogenation of 1-methyl-1,4-cyclohexadiene carried out in a custom-designed catalytic microreactor cell. The in situ catalytic microreactor cell (ICMC) with inlet/outlet ports was prepared using quartz cover as the optical window to facilitate UV-Vis observation. A fabricated thermometric stage was adapted to the UV-Vis microspectrophotometer to control the reaction temperature inside the ICMC. The spectra were collected by focusing the UV-Vis beam on a 30 × 30 µm area at the center of ICMC. At 393 K, the sequential measurement of the spectra recorded during the reaction exhibited a broad absorption peak with maximum absorbance at 260 nm that is characteristic for gaseous toluene. This result indicates that the silica supported Pt catalyst is active towards the dehydrogenation of 1-methyl-1,4-cyclohexadiene at the given experimental conditions. The onset of coke formation was also detected based on the appearance of absorption bands at 300 nm. The UV-Vis microspectroscopic system developed can be used further in studying the mechanism of the dehydrogenation reaction. © The Author(s) 2016.

  20. A comparison of antioxidative capacities of fruit juices, drinks and nectars, as determined by EPR and UV-vis spectroscopies

    Science.gov (United States)

    Bartoszek, Mariola; Polak, Justyna

    2016-01-01

    The differences in the Trolox Equivalent Antioxidant Capacity (TEAC) values at the same incubation time obtained by two different techniques: electron paramagnetic resonance (EPR) spectroscopy and ultraviolet visible (UV-vis) spectroscopy, which use the same antioxidant-free radical reaction mechanism, were determined for fruit juices, nectars and drinks. For this study, the stable free radical 1,1-Diphenyl-2-picryl-hydrazyl (DPPH•) was used. The antioxidant capacity was presented in Trolox Equivalents, e.g., μM trolox per 100 ml of sample. All of the studied fruit juices, drinks and nectars showed antioxidative properties. Dependencies between TEAC values and the percent fruit content and sample color were observed for the studied beverages. It was found that EPR spectroscopy is the more adequate method for determining TEAC values for these kinds of samples.

  1. Investigation on intermolecular interaction between berberine and β-cyclodextrin by 2D UV-Vis asynchronous spectra.

    Science.gov (United States)

    He, Anqi; Kang, Xiaoyan; Xu, Yizhuang; Noda, Isao; Ozaki, Yukihiro; Wu, Jinguang

    2017-10-05

    The interaction between berberine chloride and β-cyclodextrin (β-CyD) is investigated via 2D asynchronous UV-Vis spectrum. The occurrence of cross peaks around (420nm, 420nm) in 2D asynchronous spectrum reveals that specific intermolecular interaction indeed exists between berberine chloride and β-CyD. In spite of the difficulty caused by overlapping of cross peaks, we manage to confirm that the 420nm band of berberine undergoes a red-shift, and its bandwidth decreases under the interaction with β-CyD. The red-shift of the 420nm band that can be assigned to n-π* transition indicates the environment of berberine becomes more hydrophobic. The above spectral behavior is helpful in understanding why the solubility of berberine is enhanced by β-CyD. Copyright © 2017. Published by Elsevier B.V.

  2. Microenvironmental pH measurement during sodium naproxenate dissolution in acidic medium by UV/vis imaging

    DEFF Research Database (Denmark)

    Ostergaard, Jesper; Jensen, Henrik; Larsen, Susan W

    2014-01-01

    Variable dissolution from sodium salts of drugs containing a carboxylic acid group after passing the acidic environment of the stomach may affect oral bioavailability. The aim of the present proof of concept study was to investigate pH effects in relation to the dissolution of sodium naproxenate...... in 0.01M hydrochloric acid. For this purpose a UV/vis imaging-based approach capable of measuring microenvironmental pH in the vicinity of the solid drug compact as well as monitoring drug dissolution was developed. Using a pH indicating dye real-time spatially resolved measurement of pH was achieved....... Sodium naproxenate, can significantly alter the local pH of the dissolution medium, is eventually neutralized and precipitates as the acidic species naproxen. The developed approach is considered useful for detailed studies of pH dependent dissolution phenomena in dissolution testing....

  3. Using vis-NIR to predict soil organic carbon and clay at national scale: validation of geographically closest resampling strategy

    DEFF Research Database (Denmark)

    Peng, Yi; Knadel, Maria; Greve, Mette Balslev

    2016-01-01

    with the uncertainties of traditional laboratory wet chemistry analysis. However, for organic soils (48 samples SOC >7%) originating from wetland or forested areas the SOC predictions were generally under-estimated and not satisfactory. For prediction of clay content, only 12 out of 442 predictions were unsatisfactory......The Danish soil visible-near infrared (vis-NIR) spectral library has proved capable of predicting soil properties in Denmark such as soil organic carbon (SOC) at field scale using the geographically closest resampling strategy. However, this strategy has only been tested on one Danish local field....../farm and for future application it is necessary to extend this approach to all types of Danish soils and evaluate the predictive capabilities of the library at national scale. In the present study, partial least squares regression was used to develop models and predict topsoil SOC (490 samples) and clay contents (442...

  4. Following a Chemical Reaction on the Millisecond Time Scale by Simultaneous X-ray and UV/Vis Spectroscopy.

    Science.gov (United States)

    Olivo, Giorgio; Barbieri, Alessia; Dantignana, Valeria; Sessa, Francesco; Migliorati, Valentina; Monte, Manuel; Pascarelli, Sakura; Narayanan, Theyencheri; Lanzalunga, Osvaldo; Di Stefano, Stefano; D'Angelo, Paola

    2017-07-06

    An innovative approach aimed at disclosing the mechanism of chemical reactions occurring in solution on the millisecond time scale is presented. Time-resolved energy dispersive X-ray absorption and UV/vis spectroscopies with millisecond resolution are used simultaneously to directly follow the evolution of both the oxidation state and the local structure of the metal center in an iron complex. Two redox reactions are studied, the former involving the transformation of FeII into two subsequent FeIII species and the latter involving the more complex FeII-FeIII-FeIV-FeIII sequence. The structural modifications occurring around the iron center are correlated to the reaction mechanisms. This combined approach has the potential to provide unique insights into reaction mechanisms in the liquid phase and represents a new powerful tool to characterize short-lived intermediates that are silent to common spectroscopic techniques.

  5. A data analysis workflow to enhance clay and organic carbon models using proximal Vis-NIR data

    DEFF Research Database (Denmark)

    Tabatabai, Salman; Knadel, Maria; Greve, Mogens Humlekrog

    data preprocessing (preprocessing survey) and two variable selection methods to significantly increase visible near-infrared spectroscopy (Vis-NIRS) model performance and stability. Spectra of eight agricultural fields were measured in the range of 350-2200 nm using a mobile sensor platform (Veris......Modelling proximal sensors data is becoming a norm in soil characterization and mapping. In many cases, these models still have low predictive capabilities and lack robustness due to the large amount of noise from several environmental factors. In this study we proposed a combination of extensive...... Technologies, USA) towed by a tractor. A fuzzy c-means clustering was performed based on the first 3 principal components to select 15 representative sampling locations in each field. Clay and organic carbon (OC) were determined for all calibration samples using pipette and ignition methods, respectively...

  6. UV-vis absorption spectroscopy of carbon nanotubes: Relationship between the π-electron plasmon and nanotube diameter

    Science.gov (United States)

    Rance, Graham A.; Marsh, Dan H.; Nicholas, Robin J.; Khlobystov, Andrei N.

    2010-06-01

    The position and intensity of the π plasmon absorbance of a series of single-walled and multi-walled carbon nanotubes has been systematically investigated for the first time using ultraviolet-visible (UV-vis) absorption spectroscopy. All nanotube samples obey the Lambert-Beer law and exhibit similar extinction coefficients (˜50 mL/mg cm) regardless of their structure or method of preparation. The absolute wavelength (energy) of the π plasmon absorbance has been shown to vary with nanotube diameter as Eπ = 4.80 + 0.70/( dNT) 2. This empirical relationship when correlated with nanotube pyramidalisation angle can be used to estimate the energy range for the π plasmon in a single sheet of graphene to be 4.8-4.9 eV.

  7. Visão das cores em escolares: avaliação de um novo teste

    OpenAIRE

    Martins,Guilherme M.; Bordaberry,Marcela F.; Corrêa,Zélia M.S; Mânica,Michel B.; Costa,Juliano C.; Telichevesky,Nelson; Marcon,Ítalo M.

    2001-01-01

    OBJETIVO: comparar os resultados de um teste de visão de cores padrão (teste de Ishihara) com um teste criado pelos autores (teste do giz de cera) na detecção da discromatopsia congênita. MÉTODOS: foi realizado um estudo transversal com 712 crianças da rede escolar pública (3 escolas) e privada (1 escola) de Porto Alegre, Rio Grande do Sul. Desta amostra aleatória, haviam sido excluídas crianças com dificuldades na alfabetização e doenças sistêmicas e oculares reconhecidas. Foram aplicados se...

  8. A comparison of antioxidative capacities of fruit juices, drinks and nectars, as determined by EPR and UV-vis spectroscopies.

    Science.gov (United States)

    Bartoszek, Mariola; Polak, Justyna

    2016-01-15

    The differences in the Trolox Equivalent Antioxidant Capacity (TEAC) values at the same incubation time obtained by two different techniques: electron paramagnetic resonance (EPR) spectroscopy and ultraviolet visible (UV-vis) spectroscopy, which use the same antioxidant-free radical reaction mechanism, were determined for fruit juices, nectars and drinks. For this study, the stable free radical 1,1-Diphenyl-2-picryl-hydrazyl (DPPH(•)) was used. The antioxidant capacity was presented in Trolox Equivalents, e.g., μM trolox per 100 ml of sample. All of the studied fruit juices, drinks and nectars showed antioxidative properties. Dependencies between TEAC values and the percent fruit content and sample color were observed for the studied beverages. It was found that EPR spectroscopy is the more adequate method for determining TEAC values for these kinds of samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. SAXS Combined with UV-vis Spectroscopy and QELS: Accurate Characterization of Silver Sols Synthesized in Polymer Matrices.

    Science.gov (United States)

    Bulavin, Leonid; Kutsevol, Nataliya; Chumachenko, Vasyl; Soloviov, Dmytro; Kuklin, Alexander; Marynin, Andrii

    2016-12-01

    The present work demonstrates a validation of small-angle X-ray scattering (SAXS) combining with ultra violet and visible (UV-vis) spectroscopy and quasi-elastic light scattering (QELS) analysis for characterization of silver sols synthesized in polymer matrices. Polymer matrix internal structure and polymer chemical nature actually controlled the sol size characteristics. It was shown that for precise analysis of nanoparticle size distribution these techniques should be used simultaneously. All applied methods were in good agreement for the characterization of size distribution of small particles (less than 60 nm) in the sols. Some deviations of the theoretical curves from the experimental ones were observed. The most probable cause is that nanoparticles were not entirely spherical in form.

  10. Conformational analysis, UV-VIS, MESP, NLO and NMR studies of 6-methoxy-1,2,3,4-tetrahydronaphthalene.

    Science.gov (United States)

    Arivazhagan, M; Kavitha, R; Subhasini, V P

    2014-07-15

    The detailed HF and B3LYP/6-311++G(d,p) comparative studies on the complete FT-IR and FT-Raman spectra of 6-methoxy-1,2,3,4-tetrahydronaphthalene [MTHN] have been studied. In view of the special properties and uses, the present investigation has been undertaken to provide a satisfactorily vibrational analysis of 6-methoxy-1,2,3,4-tetrahydronaphthalene. Therefore, a thorough Raman, IR, molecular electrostatic potential (MESP), non-linear optical (NLO) properties, UV-VIS, HOMO-LUMO and NMR spectroscopic investigation are reported complemented by B3LYP theoretical predictions with basis set 6-311++G(d,p) to provide novel insight on vibrational assignments and conformational stability of MTHN. Potential energy surface scans (PES) of the CH3 group are undertaken to shed light on the rather complicated conformational interchanges in the compound under investigation. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Reactions of cytotoxic metallodrugs with lysozyme in pure DMSO explored through UV-Vis absorption spectroscopy and ESI MS.

    Science.gov (United States)

    Marzo, Tiziano; Savić, Aleksandar; Massai, Lara; Michelucci, Elena; Sabo, Tibor J; Grguric-Šipka, Sanja; Messori, Luigi

    2015-04-01

    The reactions of four representative metallodrugs with the model protein HEWL were investigated within a non-aqueous environment-i.e. in pure DMSO- through UV-Vis absorption spectroscopy and ESI MS analysis. Notably, formation of a variety of metallodrug-protein adducts was clearly documented. This is the first example for this kind of protein metalation reactions carried out within a pure organic solvent. It is shown that the applied solution conditions greatly affect the nature of the formed adducts, this being well accounted for by the fact that the overall protein conformation is greatly perturbed within pure DMSO; in addition, the activation profiles of the studied metallodrugs are also highly dependent on the nature of the solvent. The implications of these results are discussed.

  12. Chemical Speciation of the System Cu(II-Indomethacin in Ethanol and Water by UV-Vis Spectrophotometry

    Directory of Open Access Journals (Sweden)

    Norma Rodríguez-Laguna

    2016-01-01

    Full Text Available It has been proposed that the metal-drug complexes could be in fact the active agents displaying therapeutic effects of drugs. The characterization of the global formation equilibrium of complexes formed between metal ions and species with biological activity such as nonsteroidal anti-inflammatory drugs provides essential information to understand the mechanism of action of drugs. Since equilibrium constants determine the relative predominance of species, they provide crucial information to identify what complexes are more likely to be present in the system being responsible for the therapeutic effects of the drug. In this paper, the systems formed between copper and Indomethacin of different concentrations in ethanol or water were studied by UV-Vis spectrophotometry. The stoichiometry of the complexes Cu(II–Indomethacin and their formation constants were investigated. Moreover, molecular structures of the Cu(II–Indomethacin complexes were explored by means of the molecular modeling within the frame of the density functional theory.

  13. UV-vis, IR and 1H NMR spectroscopic studies and characterization of ionic-pair crystal violet-oxytetracycline.

    Science.gov (United States)

    Orellana, Sandra; Soto, César; Toral, M Inés

    2010-01-01

    The present study shows the formation and characterization of the ionic-pair between the antibiotic oxytetracycline and the dye crystal violet in ammonia solution pH 9.0+/-0.2 extracted into chloroform. The characterization was demonstrated using UV-vis spectrophotometry, (1)H NMR, measurement of relaxation times T(1) and IR spectroscopy, using a comparison between the signals of individual pure compounds with the signals with the mixture CV-OTC in different alkaline media. The formation of ionic-pair was also corroborated by new signals and chemical shifts. (2D) NMR spectroscopy experiments show that the interaction is electrostatic. Copyright 2009 Elsevier B.V. All rights reserved.

  14. SAXS Combined with UV-vis Spectroscopy and QELS: Accurate Characterization of Silver Sols Synthesized in Polymer Matrices

    Science.gov (United States)

    Bulavin, Leonid; Kutsevol, Nataliya; Chumachenko, Vasyl; Soloviov, Dmytro; Kuklin, Alexander; Marynin, Andrii

    2016-01-01

    The present work demonstrates a validation of small-angle X-ray scattering (SAXS) combining with ultra violet and visible (UV-vis) spectroscopy and quasi-elastic light scattering (QELS) analysis for characterization of silver sols synthesized in polymer matrices. Polymer matrix internal structure and polymer chemical nature actually controlled the sol size characteristics. It was shown that for precise analysis of nanoparticle size distribution these techniques should be used simultaneously. All applied methods were in good agreement for the characterization of size distribution of small particles (less than 60 nm) in the sols. Some deviations of the theoretical curves from the experimental ones were observed. The most probable cause is that nanoparticles were not entirely spherical in form.

  15. Density functional theory, restricted Hartree - Fock simulations and FTIR, FT-Raman and UV-Vis spectroscopic studies on lamotrigine

    Science.gov (United States)

    Ramya, T.; Gunasekaran, S.; Ramkumaar, G. R.

    2013-10-01

    The Fourier Transform Infrared (FTIR) and FT Raman spectra of lamotrigine have been recorded in the region 4000-450 cm-1 and 4000-50 cm-1, respectively. The title compound is used as Antiepileptic drug. The optimized geometry, frequency, and intensities of the vibrational bands of the lamotrigine were obtained by Density Functional Theory (DFT) using B3LYP/631G** basis set and ab initio method at the restricted Hartree Fock/6-31** level. The harmonic vibrational frequencies, Natural population analysis, HOMO-LUMO energy gap, infra red intensities and Raman scattering activities, force constant were calculated by DFT and RHF methods. The quality of lamotrigine under different storage containers were analyzed using UV-Vis spectral technique.

  16. UV/Vis Spectroscopy Studies of the Photoisomerization Kinetics in Self-Assembled Azobenzene-Containing Adlayers.

    Science.gov (United States)

    Krekiehn, N R; Müller, M; Jung, U; Ulrich, S; Herges, R; Magnussen, O M

    2015-08-04

    Direct comparative studies of the photoisomerization of azobenzene derivatives in self-assembled adlayers on Au and as free molecules in dichloromethane solution were performed using UV/vis spectroscopy. For all studied systems a highly reversible trans-cis isomerization in the adlayer is observed. Quantitative studies of the absorbance changes and photoisomerization kinetics reveal that in azobenzenes mounted as freestanding vertical groups on the surface via triazatriangulene-based molecular platforms photoswitching is nearly uninhibited by the local environment in the adlayer. The blue-shift of the π-π* transition in adlayers of these molecules is in good agreement with theoretical studies of the effect of excitonic coupling between the molecules. In contrast, in azobenzene-containing thiol self-assembled monolayers the fraction of photoswitching molecules and the photoisomerization kinetics are significantly reduced compared to free molecules in solution.

  17. Ambiente e saúde: visão de profissionais da saúde da família

    OpenAIRE

    Ana Flávia Quintão Fonseca

    2012-01-01

    A temática saúde e ambiente vem sendo amplamente discutida através de disciplinas tanto do campo da saúde quanto das ciências ambientais. No âmbito de uma visão ampliada de saúde, torna-se desejável que os profissionais desse campo de conhecimento apresentem um maior envolvimento na discussão acerca da temática saúde e ambiente. O objetivo deste trabalho é identificar e compreender as percepções, ideias e imagens de alguns profissionais da Saúde da Família sobre a articulação entre saúde e am...

  18. Prediction of SOC content by Vis-NIR spectroscopy at European scale using a modified local PLS algorithm

    Science.gov (United States)

    Nocita, M.; Stevens, A.; Toth, G.; van Wesemael, B.; Montanarella, L.

    2012-12-01

    In the context of global environmental change, the estimation of carbon fluxes between soils and the atmosphere has been the object of a growing number of studies. This has been motivated notably by the possibility to sequester CO2 into soils by increasing the soil organic carbon (SOC) stocks and by the role of SOC in maintaining soil quality. Spatial variability of SOC masks its slow accumulation or depletion, and the sampling density required to detect a change in SOC content is often very high and thus very expensive and labour intensive. Visible near infrared diffuse reflectance spectroscopy (Vis-NIR DRS) has been shown to be a fast, cheap and efficient tool for the prediction of SOC at fine scales. However, when applied to regional or country scales, Vis-NIR DRS did not provide sufficient accuracy as an alternative to standard laboratory soil analysis for SOC monitoring. Under the framework of Land Use/Cover Area Frame Statistical Survey (LUCAS) project of the European Commission's Joint Research Centre (JRC), about 20,000 samples were collected all over European Union. Soil samples were analyzed for several physical and chemical parameters, and scanned with a Vis-NIR spectrometer in the same laboratory. The scope of our research was to predict SOC content at European scale using LUCAS spectral library. We implemented a modified local partial least square regression (l-PLS) including, in addition to spectral distance, other potentially useful covariates (geography, texture, etc.) to select for each unknown sample a group of predicting neighbours. The dataset was split in mineral soils under cropland, mineral soils under grassland, mineral soils under woodland, and organic soils due to the extremely diverse spectral response of the four classes. Four every class training (70%) and test (30%) sets were created to calibrate and validate the SOC prediction models. The results showed very good prediction ability for mineral soils under cropland and mineral soils

  19. Evaluation of clinoptilolite for removal of ammoniacal nitrogen produced in aquaculture by Neutron activation analysis and UV-VIS spectrophotometry

    Energy Technology Data Exchange (ETDEWEB)

    Bibiano C, L.; Iturbe G, J.L.; Lopez M, B.E.; Martinez M, V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    In fish culture system, ammonia is excreted in the water as a metabolic by-product. In this work, sorption properties of clinoptilolite were determined and it was applied in culture of the rainbow trout Oncorhynchus mykiss for the removal of the ammoniacal nitrogen. The original clinoptilolite was treated with 1N NaCl solution from 24 to 192 h, for exchange NH{sub 4} ions produced in fish culture. The content of Na in the clinoptilolite was determined by neutron activation analysis. The ammonium ion content in the exchange was analysed by UV-VIS spectrophotometry. Maximum uptake of sodium was reached between 24 and 48 hours at neutral pH with granules of the clinoptilolite from 14 to 24 mesh size. The adsorption capacity was from 3.28 to 6.8 mg of ammonium per gram of clinoptilolite. (Author)

  20. Evaluation of factors in development of Vis/NIR spectroscopy models for discriminating PSE, DFD and normal broiler breast meat.

    Science.gov (United States)

    Jiang, Hongzhe; Yoon, Seung-Chul; Zhuang, Hong; Wang, Wei; Yang, Yi

    2017-12-01

    1. To evaluate the performance of visible and near-infrared (Vis/NIR) spectroscopic models for discriminating true pale, soft and exudative (PSE), normal and dark, firm and dry (DFD) broiler breast meat in different conditions of preprocessing methods, spectral ranges, characteristic wavelength selection and water-holding capacity (WHC) indexes were assessed. 2. Quality attributes of 214 intact chicken fillets (pectoralis major), such as lightness (L*), pH and WHC indicators including drip loss (DL), water gain and expressible fluid were measured. Fillets were grouped into PSE, normal and DFD categories based on combination of L*, pH and WHC threshold criteria. Classification models were developed using support vector machine based methods on characteristic wavelengths selected from the unprocessed or 2nd-derivative spectra, respectively, in three spectral subsets of 400-2500, 400-1100 and 1100-2500 nm. 3. Better classification of three meat groups was obtained based on unprocessed spectra (72-94%) than 2nd-derivative spectra (55-72%). The classification based on 400-2500 nm (91% average) and 400-1100 nm (89% average) performed better than that on 1100-2500 nm (78% average). In terms of the three different WHC indicators, the combination of L*, pH and DL produced better results than the other two groups, with recognition accuracy of 94.4% using 400-2500-nm range. 4. These analytical results suggest that for a better classification of true PSE, normal and DFD broiler breast meat with Vis/NIR spectra, unprocessed spectra wavelengths should be used, ranges of 400-1000 nm should be included in the data collection, and DL as an indicator of WHC might provide a better prediction model.

  1. Unveiling the Aggregation of Lycopene in Vitro and in Vivo: UV-Vis, Resonance Raman, and Raman Imaging Studies.

    Science.gov (United States)

    Ishigaki, Mika; Meksiarun, Phiranuphon; Kitahama, Yasutaka; Zhang, Leilei; Hashimoto, Hideki; Genkawa, Takuma; Ozaki, Yukihiro

    2017-08-31

    The present study investigates the structure of lycopene aggregates both in vitro and in vivo using ultraviolet-visible (UV-vis) and Raman spectroscopies. The electronic absorption bands of the J- and H-aggregates in vitro shift to lower and higher energies, respectively, compared to that of the lycopene monomer. Along with these results, the frequencies of the ν1 Raman bands were shifted to lower and higher frequencies, respectively. By plotting the frequencies of the ν1 Raman band against the S0 → S2 transition energy, a linear relationship between the data set with different aggregation conformations can be obtained. Therefore, the band positions depending on the different conformations can be explained based on the idea that the effective conjugated C═C chain lengths within lycopene molecules are different due to the environmental effect (site-shift effect) caused by the aggregation conformation. Applying this knowledge to the in vivo measurement of a tomato fruit sample, the relationship between the aggregation conformation of lycopene and the spectral patterns observed in the UV-vis as well as Raman spectra in different parts of tomato fruits was discussed in detail. The results showed that the concentration of lycopene (particularly that of the J-aggregate) specifically increased, whereas that of chlorophyll decreased, with ripening. Furthermore, Raman imaging indicated that lycopene with different aggregate conformations was distributed inhomogeneously, even within one sample. The layer formation in tomato tissues with high concentrations of J- and H-aggregates was successfully visualized. In this manner, the presence of lycopene distributions with different aggregate conformations was unveiled in vivo.

  2. UV-vis spectra as an alternative to the Lowry method for quantify hair damage induced by surfactants.

    Science.gov (United States)

    Pires-Oliveira, Rafael; Joekes, Inés

    2014-11-01

    It is well known that long term use of shampoo causes damage to human hair. Although the Lowry method has been widely used to quantify hair damage, it is unsuitable to determine this in the presence of some surfactants and there is no other method proposed in literature. In this work, a different method is used to investigate and compare the hair damage induced by four types of surfactants (including three commercial-grade surfactants) and water. Hair samples were immersed in aqueous solution of surfactants under conditions that resemble a shower (38 °C, constant shaking). These solutions become colored with time of contact with hair and its UV-vis spectra were recorded. For comparison, the amount of extracted proteins from hair by sodium dodecyl sulfate (SDS) and by water were estimated by the Lowry method. Additionally, non-pigmented vs. pigmented hair and also sepia melanin were used to understand the washing solution color and their spectra. The results presented herein show that hair degradation is mostly caused by the extraction of proteins, cuticle fragments and melanin granules from hair fiber. It was found that the intensity of solution color varies with the charge density of the surfactants. Furthermore, the intensity of solution color can be correlated to the amount of proteins quantified by the Lowry method as well as to the degree of hair damage. UV-vis spectrum of hair washing solutions is a simple and straightforward method to quantify and compare hair damages induced by different commercial surfactants. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. UV-Vis microspectrophotometry as a method of differentiation between cotton fibre evidence coloured with reactive dyes.

    Science.gov (United States)

    Was-Gubala, Jolanta; Starczak, Roza

    2015-05-05

    The main purposes of this study was to assess the usefulness of microspectrophotometry (MSP), both in the ultraviolet (UV) and visible (Vis) range for discriminating single cotton fibres dyed with reactive dyes coming from the same manufacturer, as well as the possibility of evaluation of the concentration of dye in an examine fibre. This study utilised woven cotton fabrics dyed with different concentrations of one-compound reactive dyes with the commercial name Cibacron® (at present Novacron®) as the focus of the MSP analysis. The spectra were recorded in the UV-Vis range between 200 and 800nm, in transmission mode. The results from this study illustrated that all of the analysed cotton samples dyed with reactive dyes were distinguishable between each other with the use of MSP, mostly in the visible, and also in ultraviolet range. The limit for applied MSP techniques was 0.18% of the concentration of a dye in the textile sample. The results indicate that based on the absorbance measurements for fibres constituting e.g. forensic traces it was not possible to estimate the concentration of the dye in the fibre because Beer's law did not obey. The intra-sample, and inter- sample variation, as well as dichroism effect in a case of a cotton fibres dyed with reactive dye were observed. On the basis of the results obtained for each analysed cotton sample, it was concluded that there was no correlation between colour uniformity in cotton fabric (changes in lightness, red/green and yellow/blue colour) and concentration of the reactive dye. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. The DisVis and PowerFit Web Servers: Explorative and Integrative Modeling of Biomolecular Complexes.

    Science.gov (United States)

    van Zundert, G C P; Trellet, M; Schaarschmidt, J; Kurkcuoglu, Z; David, M; Verlato, M; Rosato, A; Bonvin, A M J J

    2017-02-03

    Structure determination of complex molecular machines requires a combination of an increasing number of experimental methods with highly specialized software geared toward each data source to properly handle the gathered data. Recently, we introduced the two software packages PowerFit and DisVis. These combine high-resolution structures of atomic subunits with density maps from cryo-electron microscopy or distance restraints, typically acquired by chemical cross-linking coupled with mass spectrometry, respectively. Here, we report on recent advances in both GPGPU-accelerated software packages: PowerFit is a tool for rigid body fitting of atomic structures in cryo-electron density maps and has been updated to also output reliability indicators for the success of fitting, through the use of the Fisher z-transformation and associated confidence intervals; DisVis aims at quantifying the information content of distance restraints and identifying false-positive restraints. We extended its analysis capabilities to include an analysis of putative interface residues and to output an average shape representing the putative location of the ligand. To facilitate their use by a broad community, they have been implemented as web portals harvesting both local CPU resources and GPGPU-accelerated EGI grid resources. They offer user-friendly interfaces, while minimizing computational requirements, and provide a first interactive view of the results. The portals can be accessed freely after registration via http://milou.science.uu.nl/services/DISVIS and http://milou.science.uu.nl/services/POWERFIT. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  5. Detection of Outliers and Imputing of Missing Values for Water Quality UV-VIS Absorbance Time Series

    Directory of Open Access Journals (Sweden)

    Leonardo Plazas-Nossa

    2017-01-01

    Full Text Available Context: The UV-Vis absorbance collection using online optical captors for water quality detection may yield outliers and/or missing values. Therefore, data pre-processing is a necessary pre-requisite to monitoring data processing. Thus, the aim of this study is to propose a method that detects and removes outliers as well as fills gaps in time series. Method: Outliers are detected using Winsorising procedure and the application of the Discrete Fourier Transform (DFT and the Inverse of Fast Fourier Transform (IFFT to complete the time series. Together, these tools were used to analyse a case study comprising three sites in Colombia ((i Bogotá D.C. Salitre-WWTP (Waste Water Treatment Plant, influent; (ii Bogotá D.C. Gibraltar Pumping Station (GPS; and, (iii Itagüí, San Fernando-WWTP, influent (Medellín metropolitan area analysed via UV-Vis (Ultraviolet and Visible spectra. Results: Outlier detection with the proposed method obtained promising results when window parameter values are small and self-similar, despite that the three time series exhibited different sizes and behaviours. The DFT allowed to process different length gaps having missing values. To assess the validity of the proposed method, continuous subsets (a section of the absorbance time series without outlier or missing values were removed from the original time series obtaining an average 12% error rate in the three testing time series. Conclusions: The application of the DFT and the IFFT, using the 10% most important harmonics of useful values, can be useful for its later use in different applications, specifically for time series of water quality and quantity in urban sewer systems. One potential application would be the analysis of dry weather interesting to rain events, a feat achieved by detecting values that correspond to unusual behaviour in a time series. Additionally, the result hints at the potential of the method in correcting other hydrologic time series.

  6. DFT calculations and experimental FT-IR, FT-Raman, NMR, UV-Vis spectral studies of 3-fluorophenylboronic acid.

    Science.gov (United States)

    Karabacak, M; Kose, E; Sas, E B; Kurt, M; Asiri, A M; Atac, A

    2015-02-05

    The spectroscopic (FT-IR, FT-Raman, (1)H and (13)C NMR, UV-Vis), structural, electronic and thermodynamical properties of 3-fluorophenylboronic acid (C6H4FB(OH)2), 3FPBA) were submitted by using both experimental techniques and theoretical methods (quantum chemical calculations) in this work. The experimental infrared and Raman spectra were obtained in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. The equilibrium geometry and vibrational spectra were calculated by using DFT (B3LYP) with 6-311++G(d,p) basis set. The vibrational wavenumbers were also corrected with scale factor to take better results for the calculated data. The total energy distributions (TED) of the vibrational modes were performed for the assignments of the title molecule by using scaled quantum mechanics (SQM) method. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The (1)H and (13)C NMR spectra were computed by using the gauge-invariant atomic orbital (GIAO) method, showing a good agreement with the experimental ones. The last one UV-Vis absorption spectra were analyzed in two solvents (ethanol and water), saved in the range of 200-400 nm. In addition these, HOMO and LUMO energies, the excitation energies, density of states (DOS) diagrams, thermodynamical properties and molecular electrostatic potential surface (MEPs) were presented. Nonlinear optical (NLO) properties and thermodynamic features were performed. The experimental results are combined with the theoretical calculations using DFT calculations to fortification of the paper. At the end of this work, the results were proved our paper had been indispensable for the literature backing. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Evolving Synergy between UV and VIS instruments for Aerosol Remote Sensing- Implications for Suomi NPP and Future Instruments

    Science.gov (United States)

    Bhartia, P. K.; Torres, O.

    2014-12-01

    Satellite remote sensing of aerosols started in 1979 using data from the AVHRR series of instruments on NOAA polar orbiters. Though limited to the oceans only, AVHRR clearly showed the basic latitudinal, longitudinal, and seasonal patterns in global aerosol fields that have been confirmed by more advanced instruments. In the early 90s a surprising discovery was made that UV instruments, such as TOMS, designed primarily to measure atmospheric ozone, can enhance this information by tracking the aerosol absorption signal of smoke and dust plumes over both land and water, as well as over bright surfaces covered by low level clouds, snow and ice. While more recent VIS/IR mapping instruments, such as SeaWIFS, MISR, MODIS, and VIIRS have greatly enhanced aerosol remote sensing capability compared to AVHRR, similar improvements have been made in UV remote sensing of aerosols, particularly with the launch of OMI on Aura in 2004. More recently, several successful approaches have been developed to combine MODIS and OMI data to estimate aerosol single scattering albedo over cloud-free areas and aerosol optical thickness over cloudy areas. I will discuss how these advanced techniques could be applied to combine VIIRS and OMPS data from Suomi NPP and what improvements are planned for JPSS-1. These techniques could also be applied to process data from the EPIC instrument, scheduled to be launched on the DSCOVR satellite next year. It will be located 1.5 million km from the Earth along the Sun-Earth axis at the first Lagrange point. Several other UV/VIS instruments are planned to be launched in LEO and GEO orbits in this decade that can take advantage of this synergy.

  8. Balloon-borne limb profiling of UV/vis skylight radiances, O3, NO2, and BrO: technical set-up and validation of the method

    Directory of Open Access Journals (Sweden)

    F. Weidner

    2005-01-01

    Full Text Available A novel light-weight, elevation scanning and absolutely calibrated UV/vis spectrometer and its application to balloon-borne limb radiance and trace gas profile measurements is described. Its performance and the novel method of balloon-borne UV/vis limb trace gas measurements has been tested against simultaneous observations of the same atmospheric parameters available from either (a in-situ instrumentation (cf., by an electrochemical cell (ECC ozone sonde also deployed aboard the gondola or (b trace gas profiles inferred from UV/vis/near IR solar occultation measurements performed on the same payload. The novel technique is also cross validated with radiative transfer modeling. Reasonable agreement is found (a between measured and simulated limb radiances and (b inferred limb O3, NO2, and BrO and correlative profile measurements when properly accounting for all relevant atmospheric parameters (temperature, pressure, aerosol extinction, and major absorbers.

  9. Clusters de startups no Brasil: uma análise multicasos a partir da visão baseada em recursos

    OpenAIRE

    Dalcin, Thais

    2015-01-01

    O presente estudo busca compreender o desenvolvimento e a competitividade de clusters de startup no Brasil. Para a compreensão desses arranjos tecnológicos pode-se utilizar diferentes lentes teóricas, porém para o presente trabalho utilizar-se-á a Visão Baseada em Recursos e a Visão Relacional, uma vez que dirigem a atenção aos recursos-chave para o desenvolvimento desses aglomerados. Desta forma, identificaram-se na literatura treze recursos-chave relacionados aos clusters de startups, sendo...

  10. Deviation in “Vis and Rāmin” by Fakhruddin As'ad Gurgani

    Directory of Open Access Journals (Sweden)

    Masoud Forouzandeh

    2016-09-01

     Finally, from among all the norm deviations proposed by Leech, temporal, style, written, lexical and, particularly, semantic norm deviations are the ones that can be considered norm deviations to compose poems. It should be said that there were no evidence to indicate the existence of written and style norm deviations in Vis and Ramin. Totally, by analyzing the verses order of occurrence of norm deviations in Vis and Ramin is as follow: syntactic, phonetic, semantic, lexical, temporal and dialectic norm deviations. It is worth mentioning that the poet has observed the elements of conductivity and aesthetic in applying norm deviations.

  11. Uso de espectroscopia de ultravioleta visível (UV-VIS para a detecção de quercetina em plantas por meio da formação do complexo quercetina-alumínio

    Directory of Open Access Journals (Sweden)

    Fabiele BERNARDI

    2017-09-01

    Full Text Available Foram estudadas nove amostras de plantas a partir da reação de complexação que ocorre entre alumínio, proveniente do cloreto de alumínio (AlCl3 e quercetina, presente no material botânico avaliado. A reação é caracterizada pela formação de uma solução amarela, evidenciada espectroscopicamente pelo deslocamento batocrômico da região de 360-370 nm para 420-430 nm. Foram investigadas quatro amostras de pétalas: azaleia branca e magenta, lírio amarelo queimado e dente-de-leão; três amostras de folhas: babosa, laranja e lima; e duas amostras de cascas de frutos: laranja e lima. Dentre as amostras analisadas, apenas as pétalas de azaleia (Rhododendron sp. branca e magenta apresentaram concentração de quercetina suficiente para ser detectada e analisada por espectroscopia de UV-Vis pela formação do complexo quercetina-alumínio. A interação entre o alumínio e a quercetina apresenta estequiometria 2:1, com uma constante de ligação de 3,94 ± 0,34 x 103 mol L-1.

  12. Visão complexa para uma forma complexa de agir / Complex vision for a complex form of action

    Directory of Open Access Journals (Sweden)

    Maria Cecilia de Souza Minayo

    2013-02-01

    Full Text Available Este artigo contém uma introdução à abordagem científi ca denominada “pensamento complexo”, complementa a visão tradicional e racionalista da ciência, oriunda do século XVII. Os autores mostram que coexistem hoje várias formas de se pensar a produção de conhecimento. Evidenciam também que a forma com que se organiza essa produção tem muito a ver com a própria organização da sociedade, da economia e do trabalho. Por exemplo, a ciência tradicional se desenvolveu a partir da lógica da revolução industrial. Já o pensamento complexo é fruto tanto das transformações sociais como de descobertas científi cas atuais e relevantes na Física, na Matemática, na Biologia, na Cibernética e nas Ciências Sociais. O texto termina mostrando que a visão complexa da ciência é fundamental para transformar as formas de pensar e de agir em saúde, particularmente, para a vigilância sanitária, para a formação de pessoas e para a gestão dos serviços. ------------------------------------------------------- This article contains an introduction to the scientifi c approach called “complex thought” that complements the traditional view of science and rationalism, coming from the seventeenth century. The authors show that coexist today several ways of thinking about knowledge production. Also show that the way that production is organized has a lot to do with the very organization of society, economy and labor. For example, the rationalist science has developed from traditional logic of the industrial revolution. Already, complex thinking is fruit of contemporary social changes and relevant scientifi c discoveries in physics, mathematics, biology, cybernetics and social sciences. The text ends by showing that the complex view of science is essential to transform the ways of thinking and acting on health, particularly for surveillance, to train people and for the management of services.

  13. Assessing Pearl Quality Using Reflectance UV-Vis Spectroscopy: Does the Same Donor Produce Consistent Pearl Quality?

    Science.gov (United States)

    Mamangkey, Noldy Gustaf F.; Agatonovic, Snezana; Southgate, Paul C.

    2010-01-01

    Two groups of commercial quality (“acceptable”) pearls produced using two donors, and a group of “acceptable” pearls from other donors were analyzed using reflectance UV-Vis spectrophotometry. Three pearls with different colors produced by the same donor showed different absorption spectra. Cream and gold colored pearls showed a wide absorption from 320 to about 460 nm, while there was just slight reflectance around 400 nm by the white pearl with a pink overtone. Cream and gold pearls reached a reflectance peak at 560 to 590 nm, while the white pearl with pink overtone showed slightly wider absorption in this region. Both cream and gold pearls showed an absorption peak after the reflectance peak, at about 700 nm for the cream pearl and 750 nm for the gold pearl. Two other pearls produced by the same donor (white with cream overtone and cream with various overtones) showed similar spectra, which differed in their intensity. One of these pearls had very high lustre and its spectrum showed a much higher percentage reflectance than the second pearl with inferior lustre. This result may indicate that reflectance is a useful quantitative indicator of pearl lustre. The spectra of two white pearls resulting from different donors with the same color nacre (silver) showed a reflectance at 260 nm, followed by absorption at 280 nm and another reflectance peak at 340 nm. After this peak the spectra for these pearls remained flat until a slight absorption peak around 700 nm. Throughout the visible region, all white pearls used in this study showed similar reflectance spectra although there were differences in reflectance intensity. Unlike the spectral results from white pearls, the results from yellow and gold pearls varied according to color saturation of the pearl. The results of this study show that similarities between absorption and reflectance spectra of cultured pearls resulting from the same saibo donor are negligible and could not be detected with UV-Vis

  14. Assessing pearl quality using reflectance UV-Vis spectroscopy: does the same donor produce consistent pearl quality?

    Science.gov (United States)

    Mamangkey, Noldy Gustaf F; Agatonovic, Snezana; Southgate, Paul C

    2010-09-20

    Two groups of commercial quality ("acceptable") pearls produced using two donors, and a group of "acceptable" pearls from other donors were analyzed using reflectance UV-Vis spectrophotometry. Three pearls with different colors produced by the same donor showed different absorption spectra. Cream and gold colored pearls showed a wide absorption from 320 to about 460 nm, while there was just slight reflectance around 400 nm by the white pearl with a pink overtone. Cream and gold pearls reached a reflectance peak at 560 to 590 nm, while the white pearl with pink overtone showed slightly wider absorption in this region. Both cream and gold pearls showed an absorption peak after the reflectance peak, at about 700 nm for the cream pearl and 750 nm for the gold pearl. Two other pearls produced by the same donor (white with cream overtone and cream with various overtones) showed similar spectra, which differed in their intensity. One of these pearls had very high lustre and its spectrum showed a much higher percentage reflectance than the second pearl with inferior lustre. This result may indicate that reflectance is a useful quantitative indicator of pearl lustre. The spectra of two white pearls resulting from different donors with the same color nacre (silver) showed a reflectance at 260 nm, followed by absorption at 280 nm and another reflectance peak at 340 nm. After this peak the spectra for these pearls remained flat until a slight absorption peak around 700 nm. Throughout the visible region, all white pearls used in this study showed similar reflectance spectra although there were differences in reflectance intensity. Unlike the spectral results from white pearls, the results from yellow and gold pearls varied according to color saturation of the pearl. The results of this study show that similarities between absorption and reflectance spectra of cultured pearls resulting from the same saibo donor are negligible and could not be detected with UV-Vis

  15. Ten years of OMI observations: scientific highlights and impacts on the new generation of UV/VIS satellite instrumentation

    Science.gov (United States)

    Levelt, Pieternel; Veefkind, Pepijn; Bhartia, Pawan; Joiner, Joanna; Tamminen, Johanna; OMI Science Team

    2014-05-01

    On July 15, 2004 Ozone Monitoring Instrument (OMI) was successfully launched from the Vandenberg military air force basis in California, USA, on NASA's EOS-Aura spacecraft. OMI is the first of a new generation of UV/VIS nadir solar backscatter imaging spectrometers, which provides nearly global coverage in one day with an unprecedented spatial resolution of 13 x 24 km2. OMI measures solar irradiance and Earth radiances in the wavelength range of 270 to 500 nm with a spectral resolution of about 0.5 nm. OMI is designed and built by the Netherlands and Finland and is also a third party mission of ESA. The major step that was made in the OMI instrument compared to its predecessors is the use of 2-dimensional detector arrays (CCDs) in a highly innovative small optical design. These innovations enable the combination of a high spatial resolution and a good spectral resolution with daily global coverage. OMI measures a range of trace gases (O3, NO2, SO2, HCHO, BrO, OClO, H2O), clouds and aerosols. Albeit OMI is already 5 years over its design lifetime, the instrument is still fully operational. The successor of OMI is TROPOMI (TROPOspheric Monitoring Instrument) on the Copernicus Sentinel-5 precursor mission, planned for launch in 2015. OMI's unique capabilities rely in measuring tropospheric trace gases with a small footprint and daily global coverage. The unprecedented spatial resolution of the instrument revealed for the first time tropospheric pollution maps on a daily basis with urban scale resolution leading to improved air quality forecasts. The OMI measurements also improve our understanding of air quality and the interaction between air quality and climate change by combining measurements of air pollutants and aerosols. In recent years the data are also used for obtaining high-resolution global emission maps using inverse modelling or related techniques, challenging the bottom-up inventories based emission maps. In addition to scientific research, OMI also

  16. Aerosol radiative effect in UV, VIS, NIR, and SW spectra under haze and high-humidity urban conditions

    Science.gov (United States)

    Zhang, Ming; Ma, Yingying; Gong, Wei; Wang, Lunche; Xia, Xiangao; Che, Huizheng; Hu, Bo; Liu, Boming

    2017-10-01

    Aerosol properties derived from sun-photometric observations at Wuhan during a haze period were analyzed and used as input in a radiative transfer model to calculate the aerosol radiative effect (ARE) in ultraviolet (UV), visible (VIS), near-infrared (NIR), and shortwave (SW) spectra. The results showed that the aerosol optical depth (AOD) at 440 nm increased from 0.32 under clear-air conditions to 0.85 during common haze and 1.39 during severe haze. An unusual inverse relationship was found between the Ångström exponent (AE) and AOD during the haze period at Wuhan. Under high-humidity conditions, the fine-mode median radius of aerosols increased from 0.113 μm to approximately 0.2-0.5 μm as a result of hygroscopic growth, which led to increases in the AOD and decreases in the AE simultaneously. These changes were responsible for the inverse relationship between AE and AOD at Wuhan. The surface ARE in the UV (AREUV), VIS (AREVIS), NIR (ARENIR), and SW (ARESW) spectra changed from -4.46, -25.37, -12.15, and -41.99 W/m2 under clear-air conditions to -9.48, -53.96, -29.81, and -93.25 W/m2 during common hazy days and -12.89, -80.16, -55.17, and -148.22 W/m2 during severe hazy days, respectively, and the percentages of AREUV, AREVIS, and ARENIR in ARESW changed from 11%, 61%, and 28%-9%, 54%, and 37%, respectively. Meanwhile, the ARE efficiencies (REE) in SW varied from -206.5 W/m2 under clear-air conditions to -152.94 W/m2 during the common haze period and -131.47 W/m2 during the severe haze period. The smallest decreasing rate of the REE in NIR was associated with the increase of ARENIR. The weakened REE values were related to the strong forward scattering and weak backward scattering of fine aerosol particles with increasing size resulting from hygroscopic growth, while the variation of the single scattering albedo showed less impact. Source region analysis by back trajectories and the concentration weighted trajectory (CWT) method showed that black carbon came

  17. [Identification methods of crop and weeds based on Vis/NIR spectroscopy and RBF-NN model].

    Science.gov (United States)

    Zhu, Deng-Sheng; Pan, Jia-Zhi; He, Yong

    2008-05-01

    The automated recognition of crop and weed by using Vis/NIR spectral in field is one of hottest research branches of agriculture engineering. If the recognition is efficient and effective, then the variate operations of herbicide or fertilizer spraying in field could be realized. Many researches have pointed out that the reflectance rate of green plant leaves could be used to identify the varieties. As the colors and surface textures of crop and weed were change in different living phases, these changes may exert great influence on the reflectance spectral of plant leaves. Vis/NIR spectra of three weeds and one crop in two different terms were recorded by spectral meter ASD FieldSpec Pro FR. Its wave band is from 325 to 1 075 nm. The scan time was 270 ms. The scanning times of per sample was set to 30 times. Firstly, 23 days after the planting of soybean, some soybean leaves and weeds leave were picked from the field, and brought to lab to record spectral. The lighting condition was controlled by an artificial halogen bulb. Secondly, on the 45th day, the same experiment was done. The three weeds were goose grass, alligator alternanthera and emarginate amaranth. The crop was soybean seedling. Totally 378 samples were drawn for two terms. As one original reflectance spectrum contains 651 float numbers, the total data volume was huge. Using wavelet transform to compress data volume and extract characteristic spectral data was tried. The result was 114 float numbers per sample. Among them, 250 samples from two terms were used as input data to build artificial neural network model, and those left were used to check the validation. Radial basis function neural network model is widely used in pattern recognition problems. It is a nonlinear and self adaptive parallel. By assigning a 1 by 4 vector to each spectral samples, the source data could be used to build an RBF-NN model. All the samples were assigned these standard output data. Then, the left 128 samples were used to

  18. Assessing Pearl Quality Using Reflectance UV-Vis Spectroscopy: Does the Same Donor Produce Consistent Pearl Quality?

    Directory of Open Access Journals (Sweden)

    Paul C. Southgate

    2010-09-01

    Full Text Available Two groups of commercial quality (“acceptable” pearls produced using two donors, and a group of “acceptable” pearls from other donors were analyzed using reflectance UV-Vis spectrophotometry. Three pearls with different colors produced by the same donor showed different absorption spectra. Cream and gold colored pearls showed a wide absorption from 320 to about 460 nm, while there was just slight reflectance around 400 nm by the white pearl with a pink overtone. Cream and gold pearls reached a reflectance peak at 560 to 590 nm, while the white pearl with pink overtone showed slightly wider absorption in this region. Both cream and gold pearls showed an absorption peak after the reflectance peak, at about 700 nm for the cream pearl and 750 nm for the gold pearl. Two other pearls produced by the same donor (white with cream overtone and cream with various overtones showed similar spectra, which differed in their intensity. One of these pearls had very high lustre and its spectrum showed a much higher percentage reflectance than the second pearl with inferior lustre. This result may indicate that reflectance is a useful quantitative indicator of pearl lustre. The spectra of two white pearls resulting from different donors with the same color nacre (silver showed a reflectance at 260 nm, followed by absorption at 280 nm and another reflectance peak at 340 nm. After this peak the spectra for these pearls remained flat until a slight absorption peak around 700 nm. Throughout the visible region, all white pearls used in this study showed similar reflectance spectra although there were differences in reflectance intensity. Unlike the spectral results from white pearls, the results from yellow and gold pearls varied according to color saturation of the pearl. The results of this study show that similarities between absorption and reflectance spectra of cultured pearls resulting from the same saibo donor are negligible and could not be detected

  19. Identification of Intermediates in Zeolite-Catalyzed Reactions Using In-situ UV/Vis Micro- Spectroscopy and a Complementary Set of Molecular Simulations

    NARCIS (Netherlands)

    Hemelsoet, K.L.J.; Qian, Q.; De Meyer, T.; De Wispelaere, K.; De Sterck, B.; Weckhuysen, B.M.; Waroquier, M.; Van Speybroeck, V.

    2013-01-01

    The optical absorption properties of (poly)aromatic hydrocarbons occluded in a nanoporous environment were investigated by theoretical and experimental methods. The carbonaceous species are an essential part of a working catalyst for the methanol-toolefins (MTO) process. In situ UV/Vis microscopy

  20. LC-MS of Metmyoglobin at pH = 2: Separation and Characterization of Apomyoglobin and Heme by ESI-MS and UV-Vis

    Science.gov (United States)

    Stynes, Helen Cleary; Layo, Araceli; Smith, Richard W.

    2004-01-01

    The protein species of apomyoglobin (apoMb) and heme are freed and segregated from the aqueous protein solution of metmyoglobin by liquid chromatography, and are distinguished by UV-Vis absorption or electrospray ionization mass spectrometry (ESI-MS). This is an ingenious and effective approach to characterize apomyoglobin and heme, while students…

  1. The Catalytic Conversion of Thiophenes over Large H-ZSM-5 Crystals: An X-Ray, UV/Vis, and Fluorescence Microspectroscopic Study

    NARCIS (Netherlands)

    Kox, M.H.F.; Mijovilovich, A.E.; S ättler, J.J.H.B.; Stavitski, I.; Weckhuysen, B.M.

    2013-01-01

    X-ray absorption, UV/Vis, and fluorescence microspectroscopy have been used to characterize the catalytic conversion of thiophene derivatives within the micropores of an individual H-ZSM-5 zeolite crystal. Space-resolved information into the Si/ Al ratios and sulfur content was provided by X-ray

  2. Predicting the Shifts of Absorption Maxima of Azulene Derivatives Using Molecular Modeling and ZINDO CI Calculations of UV-Vis Spectra

    Science.gov (United States)

    Patalinghug, Wyona C.; Chang, Maharlika; Solis, Joanne

    2007-01-01

    The deep blue color of azulene is drastically changed by the addition of substituents such as CH[subscript 3], F, or CHO. Computational semiempirical methods using ZINDO CI are used to model azulene and azulene derivatives and to calculate their UV-vis spectra. The calculated spectra are used to show the trends in absorption band shifts upon…

  3. Combined Operando UV/Vis/IR Spectroscopy Reveals the Role of Methoxy and Aromatic Species during the Methanol-to-Olefins Reaction over H-SAPO-34

    NARCIS (Netherlands)

    Qian, Qingyun; Vogt, Charlotte; Mokhtar, Mohamed; Asiri, Abdullah M.; Al-Thabaiti, Shaeel A.; Basahel, Suliman N.; Ruiz-Martinez, Javier; Weckhuysen, Bert M.

    2014-01-01

    The methanol-to-olefins (MTO) process over H-SAPO-34 is investigated by using an operando approach combining UV/Vis and IR spectroscopies with on-line mass spectrometry. Methanol, methoxy, and protonated dimethyl ether are the major species during the induction period, whereas polyalkylated benzenes

  4. Operando UV-Vis spectroscopy of a catalytic solid in a pilos-scale reactor: deactivation of a CrOx/Al2O3 propane dehydrogenation catalyst

    NARCIS (Netherlands)

    Sattler, J.J.H.B.; Gonzalez-Jimenez, I.D.; Mens, A.J.M.; Arias, M.J.; Visser, T.; Weckhuysen, B.M.

    2013-01-01

    A novel operando UV-Vis spectroscopic set-up has been constructed and tested for the investigation of catalyst bodies loaded in a pilot-scale reactor under relevant reaction conditions. Spatiotemporal insight into the formation and burning of coke deposits on an industrial CrOx/Al2O3 catalyst during

  5. A novel combined approach of diffuse reflectance UV-Vis-NIR spectroscopy and multivariate analysis for non-destructive examination of blue ballpoint pen inks in forensic application.

    Science.gov (United States)

    Kumar, Raj; Sharma, Vishal

    2017-03-15

    The present research is focused on the analysis of writing inks using destructive UV-Vis spectroscopy (dissolution of ink by the solvent) and non-destructive diffuse reflectance UV-Vis-NIR spectroscopy along with Chemometrics. Fifty seven samples of blue ballpoint pen inks were analyzed under optimum conditions to determine the differences in spectral features of inks among same and different manufacturers. Normalization was performed on the spectroscopic data before chemometric analysis. Principal Component Analysis (PCA) and K-mean cluster analysis were used on the data to ascertain whether the blue ballpoint pen inks could be differentiated by their UV-Vis/UV-Vis NIR spectra. The discriminating power is calculated by qualitative analysis by the visual comparison of the spectra (absorbance peaks), produced by the destructive and non-destructive methods. In the latter two methods, the pairwise comparison is made by incorporating the clustering method. It is found that chemometric method provides better discriminating power (98.72% and 99.46%, in destructive and non-destructive, respectively) in comparison to the qualitative analysis (69.67%). Copyright © 2016 Elsevier B.V. All rights reserved.

  6. UV-Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 1: basic principles and properties of tyrosine chromophore.

    Science.gov (United States)

    Antosiewicz, Jan M; Shugar, David

    2016-06-01

    Spectroscopic properties of tyrosine residues may be employed in structural studies of proteins. Here we discuss several different types of UV-Vis spectroscopy, like normal, difference and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, and corresponding optical properties of the tyrosine chromophore, phenol, which are used to study protein structure.

  7. Corneal biomechanical characteristics measured by the CorVis Scheimpflug technology in eyes with primary open-angle glaucoma and normal eyes.

    Science.gov (United States)

    Tian, Lei; Wang, Dajiang; Wu, Ying; Meng, Xiaoli; Chen, Bing; Ge, Mei; Huang, Yifei

    2016-08-01

    To evaluate the biomechanical properties of the cornea using Corneal Visualization Scheimpflug Technology (CorVis ST, Oculus) in eyes with primary open-angle glaucoma (POAG) and normal control eyes. A comparative cross-sectional study that included 42 patients with POAG and 60 normal control subjects matched for intraocular pressure (IOP) and central corneal thickness (CCT). IOP was measured with a Goldmann applanation tonometer (GAT). Corneal tomography and biomechanical parameters were measured with Pentacam (Oculus) and CorVis ST, respectively. Corneal biomechanical properties were compared between groups, and the associations between corneal biomechanical parameters and ocular characteristics were evaluated. Receiver operating characteristic (ROC) curves were used to establish a cut-off value for the biomechanical parameters. The following parameters of the CorVis ST showed a significant difference between eyes with POAG and normal eyes: first applanation velocity (Vin ), second applanation time (A-time2 ), peak distance (PD) and deformation amplitude (DA). In the univariate analysis, DA was negatively correlated with IOP in both groups. For all biomechanical parameters, the areas under the ROC curve were corneal biomechanical properties. Eyes with POAG exhibit a faster Vin , longer A-time2 , lower DA and longer PD than do IOP- and CCT-matched normal control eyes. The biomechanical parameters of the CorVis ST cannot readily be used for diagnosis of POAG in the individual patient. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  8. Data of fluorescence, UV–vis absorption and FTIR spectra for the study of interaction between two food colourants and BSA

    OpenAIRE

    LI, Tian; Cheng, Zhengjun; Cao, Lijun; Jiang, Xiaohui; Fan,Lei

    2016-01-01

    In this data article, the fluorescence, UV–vis absorption and FTIR spectra data of BSA-AR1/AG50 system were presented, which were used for obtaining the binding characterization (such as binding constant, binding distance, binding site, thermodynamics, and structural stability of protein) between BSA and AR1/AG50.

  9. Synthesis of a novel camphorquinone derivative having acylphosphine oxide group, characterization by UV-VIS spectroscopy and evaluation of photopolymerization performance

    National Research Council Canada - National Science Library

    IKEMURA, Kunio; ICHIZAWA, Kensuke; JOGETSU, Yoshiyuki; ENDO, Takeshi

    2010-01-01

    .... Newly synthesized CQ-APO showed as a pale yellow crystal (mp 365K). UV-VIS spectrum of CQ-APO showed two maximum absorption wavelengths (λmax) [372 nm (from APO group) and 475 nm (from CQ moiety)] within 350-500 nm...

  10. A novel combined approach of diffuse reflectance UV-Vis-NIR spectroscopy and multivariate analysis for non-destructive examination of blue ballpoint pen inks in forensic application

    Science.gov (United States)

    Kumar, Raj; Sharma, Vishal

    2017-03-01

    The present research is focused on the analysis of writing inks using destructive UV-Vis spectroscopy (dissolution of ink by the solvent) and non-destructive diffuse reflectance UV-Vis-NIR spectroscopy along with Chemometrics. Fifty seven samples of blue ballpoint pen inks were analyzed under optimum conditions to determine the differences in spectral features of inks among same and different manufacturers. Normalization was performed on the spectroscopic data before chemometric analysis. Principal Component Analysis (PCA) and K-mean cluster analysis were used on the data to ascertain whether the blue ballpoint pen inks could be differentiated by their UV-Vis/UV-Vis NIR spectra. The discriminating power is calculated by qualitative analysis by the visual comparison of the spectra (absorbance peaks), produced by the destructive and non-destructive methods. In the latter two methods, the pairwise comparison is made by incorporating the clustering method. It is found that chemometric method provides better discriminating power (98.72% and 99.46%, in destructive and non-destructive, respectively) in comparison to the qualitative analysis (69.67%).

  11. A integralidade na visão dos fisioterapeutas de um município de médio porte

    Directory of Open Access Journals (Sweden)

    Angela Carla Ghizoni

    Full Text Available Objetivou-se conhecer a visão dos fisioterapeutas acerca da integralidade em um município de médio porte. Foram utilizados questionários autoaplicados e entrevistas em profundidade com seis deles. Optou-se pela análise de conteúdo para tratamento dos dados. Emergiram seis diferentes faces da integralidade: holística (visão do paciente como um todo, ampliada (consideração do contexto e determinantes sociais da saúde-doença, interdisciplinar (visão interdisciplinar contrastada com a sua ausência prática, oculta (desconhecimento do termo; com indícios de prática da integralidade no cotidiano, fragmentária (visão mecânica do corpo e face nula (desconhecimento e indiferença. Essas diversas e contraditórias faces indicam que a adoção de práticas mais integrais pelos fisioterapeutas deve ser fomentada nos serviços privados e públicos. Para tanto, ressalta-se a importância da formação profissional e da educação permanente e continuada como duas das várias dimensões que configuram o exercício profissional como uma prática socialmente construída.

  12. Hydration effects on the molecular structure of silica-supported vanadium oxide catalysts: A combined IR, Raman, UV–vis and EXAFS study

    NARCIS (Netherlands)

    Keller, D.E.; Visser, T.|info:eu-repo/dai/nl/110288327; Soulimani, F.|info:eu-repo/dai/nl/313889449; Koningsberger, D.C.|info:eu-repo/dai/nl/073704342; Weckhuysen, B.M.|info:eu-repo/dai/nl/285484397

    2007-01-01

    The effect of hydration on the molecular structure of silica-supported vanadium oxide catalysts with loadings of 1–16 wt.% V has been systematically investigated by infrared, Raman, UV–vis and EXAFS spectroscopy. IR and Raman spectra recorded during hydration revealed the formation of V–OH groups,

  13. A mid-Tournaisian-late Viséan carbonate ramp reconstructed from nappes and olistolites in the southern Montagne Noire (France)

    Science.gov (United States)

    Cózar, P.; Izart, A.; Vachard, D.; Coronado, I.

    2017-08-01

    The mainly calcareous succession from the mid Tournaisian to the lower part of the upper Viséan in the Southern Montagne Noire Mont Peyroux nappes and Cabrières slices is sedimentologically revised. From the late Viséan, the Variscan orogeny affected the area, and the studied Mississippian part of the succession was considered as part (together with the Devonian) of a period of tectonic quiescence, later included as nappes and olistolites in a wildflysch. This study presents the facies from pelagic limestones, calciturbidites, bioclastic limestones and microbial limestones, and the relationship between platform and calciturbidites in the pre-orogenic context of the Montagne Noire basin during the Mississippian. The differences in the lithostratigraphy is analyzed by means of four tectonostratigraphical units (Mont Peyroux nappe, Roquessels band, Cabrières area and La Serre band) previously defined by other authors, that together with the deep-water Vieussan-Caragnas unit (not studied here due to the poverty in chronostratigraphical data) allow reconstructing the original carbonate platform. The latter seems to correspond to a ramp for the latest Tournaisian to early Viséan, and a distally-steppened ramp from the middle Viséan to the early late Viséan, including basin plain to slope as the deepest water environments, and middle ramp as the shallowest, except for the uppermost part of the succession, where the inner ramp is recognized. During this period, the shallowing tendency in the tectonostratigraphic units is well marked: Mont Peyroux nappe - Roquessels band - Cabrières area - La Serre band (from deeper to shallower), which differs from the shallowing trend defined by previous authors during the Devonian. Strong similarities are observed with the preserved Mississippian carbonates in the Mouthoumet Massif to the south, which might represent the shallowest water deposits of the ramp, not preversed in the Cabrières-La Serre areas.

  14. ESTIMACIÓN DEL EXPONENTE DE HURST Y DIMENSIÓN FRACTAL PARA EL ANÁLISIS DE SERIES DE TIEMPO DE ABSORBANCIA UV-VIS

    Directory of Open Access Journals (Sweden)

    Leonardo Plazas Nossa

    2014-01-01

    Full Text Available El objetivo de este trabajo es estimar el exponente o parámetro de Hurst y la dimensión fractal para el análisis de series de tiempo de espectrometría UV-Vis, utilizando el análisis de componentes principales PCA (Principal Component Analysis. El análisis se realiza para comprender si las series de tiempo de absorbancia UV-Vis son persistentes, anti-persistentes, determinísticas o si son ruido blanco. Se utilizaron tres diferentes series de tiempo de absorbancia UV-Vis para tres diferentes sitios de estudio: (i Planta de tratamiento de aguas residuales Salitre (PTAR en Bogotá; (ii Estación elevadora de Gibraltar en Bogotá (EEG; y (iii Planta de tratamiento de aguas residuales San Fernando (PTAR en Itagüí (sur de Medellín. Cada una de las series de tiempo tiene igual número de muestras (5705. Se redujo la dimensionalidad de los espectros de absorbancia, dada su alta correlación, con PCA y se utilizó para cada sitio de estudio la primera componente principal. Esta componente principal explicó entre el 82% al 94% de la variabilidad para los tres sitios de estudio. Se determinaron los exponentes de Hurst: (i 0.8 para PTAR Salitre; (ii 0.85 para EEG; y (iii 0.89 para PTAR San Fernando. A partir de los valores de los exponentes de Hurst se determinan las dimensiones fractales para las tres series de tiempo de absorbancia UV-Vis en los tres sitios de estudio y se obtiene en promedio una dimensión fractal de 1153. Las tres series de tiempo de absorbancia UV-Vis son persistentes y con alta auto-similitud, dado que el exponente de Hurst es mayor a 0.5.

  15. VisIO: enabling interactive visualization of ultra-scale, time-series data via high-bandwidth distributed I/O systems

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Christopher J [Los Alamos National Laboratory; Ahrens, James P [Los Alamos National Laboratory; Wang, Jun [UCF

    2010-10-15

    Petascale simulations compute at resolutions ranging into billions of cells and write terabytes of data for visualization and analysis. Interactive visuaUzation of this time series is a desired step before starting a new run. The I/O subsystem and associated network often are a significant impediment to interactive visualization of time-varying data; as they are not configured or provisioned to provide necessary I/O read rates. In this paper, we propose a new I/O library for visualization applications: VisIO. Visualization applications commonly use N-to-N reads within their parallel enabled readers which provides an incentive for a shared-nothing approach to I/O, similar to other data-intensive approaches such as Hadoop. However, unlike other data-intensive applications, visualization requires: (1) interactive performance for large data volumes, (2) compatibility with MPI and POSIX file system semantics for compatibility with existing infrastructure, and (3) use of existing file formats and their stipulated data partitioning rules. VisIO, provides a mechanism for using a non-POSIX distributed file system to provide linear scaling of 110 bandwidth. In addition, we introduce a novel scheduling algorithm that helps to co-locate visualization processes on nodes with the requested data. Testing using VisIO integrated into Para View was conducted using the Hadoop Distributed File System (HDFS) on TACC's Longhorn cluster. A representative dataset, VPIC, across 128 nodes showed a 64.4% read performance improvement compared to the provided Lustre installation. Also tested, was a dataset representing a global ocean salinity simulation that showed a 51.4% improvement in read performance over Lustre when using our VisIO system. VisIO, provides powerful high-performance I/O services to visualization applications, allowing for interactive performance with ultra-scale, time-series data.

  16. O cuidado de enfermagem: uma visão fenomenológica do ser leucêmico

    Directory of Open Access Journals (Sweden)

    Catarina Aparecida Sales

    1999-06-01

    Full Text Available Este trabalho é uma investigação sobre o cuidado de enfermagem na visão do ser leucêmico. A pesquisadora parte de inquietações emergidas em seu cotidiano enquanto, enfermeira assistencial e docente de enfermagem, buscando a apreender o sentido do cuidado no existir diário do ser leucêmico, enquanto um ser-no-mundo. Apresenta uma reflexão sobre o caminho a ser percorrido, e encontra na pesquisa qualitativa fenomenológica, no enfoque hermenêutico, fundamentado no pensar de Martin Heidegger, o método para desvelar o velado no discurso dos sujeitos, demonstrando que o ser leucêmico percebe o cuidado de enfermagem como: forma inautêntica de estar-com, assistir de forma diferenciada, paciência e compreensão e forma autêntica de estar-com. Ao desvelar o sentido emergido nos discursos, a pesquisadora percebe-se re-aprendendo a cuidar, através da linguagem dos sujeitos investigados.

  17. Solvent dependency of the UV-Vis spectrum of indenoisoquinolines: role of keto-oxygens as polarity interaction probes.

    Directory of Open Access Journals (Sweden)

    Andrea Coletta

    Full Text Available Indenoisoquinolines are the most promising non-campthotecins topoisomerase IB inhibitors. We present an integrated experimental/computational investigation of the UV-Vis spectra of the IQNs parental compound (NSC314622 and two of its derivatives (NSC724998 and NSC725776 currently undergoing Phase I clinical trials. In all the three compounds a similar dependence of the relative absorption intensities at 270 nm and 290 nm on solvent polarity is found. The keto-oxygens in positions 5 and 11 of the molecular scaffold of the molecule are the principal chromophores involved in this dependence. Protic interactions on these sites are also found to give rise to absorptions at wavelength <250 nm observed in water solution, due to the stabilization of highly polarized tautomers of the molecule. These results suggest that the keto-oxygens are important polarizable groups that can act as useful interactors with the molecular receptor, providing at the same time an useful fingerprint for the monitoring of the drug binding to topoisomerase IB.

  18. Solvent Dependency of the UV-Vis Spectrum of Indenoisoquinolines: Role of Keto-Oxygens as Polarity Interaction Probes

    Science.gov (United States)

    Coletta, Andrea; Castelli, Silvia; Chillemi, Giovanni; Sanna, Nico; Cushman, Mark; Pommier, Yves; Desideri, Alessandro

    2013-01-01

    Indenoisoquinolines are the most promising non-campthotecins topoisomerase IB inhibitors. We present an integrated experimental/computational investigation of the UV-Vis spectra of the IQNs parental compound (NSC314622) and two of its derivatives (NSC724998 and NSC725776) currently undergoing Phase I clinical trials. In all the three compounds a similar dependence of the relative absorption intensities at 270 nm and 290 nm on solvent polarity is found. The keto-oxygens in positions 5 and 11 of the molecular scaffold of the molecule are the principal chromophores involved in this dependence. Protic interactions on these sites are also found to give rise to absorptions at wavelength <250 nm observed in water solution, due to the stabilization of highly polarized tautomers of the molecule. These results suggest that the keto-oxygens are important polarizable groups that can act as useful interactors with the molecular receptor, providing at the same time an useful fingerprint for the monitoring of the drug binding to topoisomerase IB. PMID:24086299

  19. Q-mode curve resolution of UV-vis spectra for structural transformation studies of anthocyanins in acidic solutions

    Energy Technology Data Exchange (ETDEWEB)

    Marco, Paulo Henrique [Laboratorio de Quimiometria em Ciencias Naturais, Departamento de Quimica, Universidade Estadual de Londrina, Caixa Postal 6001, CEP 86051-970 Londrina, Parana (Brazil); Scarminio, Ieda Spacino [Laboratorio de Quimiometria em Ciencias Naturais, Departamento de Quimica, Universidade Estadual de Londrina, Caixa Postal 6001, CEP 86051-970 Londrina, Parana (Brazil)]. E-mail: ieda@qui.uel.br

    2007-01-30

    Chemometric analysis of ultraviolet-visible (UV-vis) spectra for pH values 1.0, 3.3, 5.3, and 6.9 was used to investigate the kinetics and the structural transformations of anthocyanins in extracts of calyces of hibiscus flowers of the Hibiscus acetosella Welw. ex Finicius for the first time. Six different species were detected: the quinoidal base (A), the flavylium cation (AH{sup +}), the pseudobase or carbinol pseudobase (B), cis-chalcone (C{sub C}), trans-chalcone (C{sub t}), and ionized cis-chalcone (C{sub C}{sup -}). Four equilibrium constant values were calculated using relative concentrations, hydration, pK{sub h}=2.60+/-0.01, tautomeric, K{sub T}=0.14+/-0.01, acid-base, pK{sub a}=4.24+/-0.04, and ionization of the cis-chalcone, pK{sub C{sub C}}=8.74+/-1.5x10{sup -2}. The calculated protonation rate of the tautomers is K{sub H{sup +}}=0.08+/-7.6x10{sup -3}. These constants are in excellent agreement with those measured previously in salt form. From a kinetic viewpoint, the situation encountered is interesting since the reported investigation is limited to visible light absorption in acid medium. These models have not been reported in the literature.

  20. UV-Vis spectroscopic study and DFT calculation on the solvent effect of trimethoprim in neat solvents and aqueous mixtures

    Science.gov (United States)

    Almandoz, M. C.; Sancho, M. I.; Duchowicz, P. R.; Blanco, S. E.

    2014-08-01

    The solvatochromic behavior of trimethoprim (TMP) was analyzed using UV-Vis spectroscopy and DFT methods in neat and binary aqueous solvent mixtures. The effects of solvent dipolarity/polarizability and solvent-solute hydrogen bonding interactions on the absorption maxima were evaluated by means of the linear solvation energy relationship concept of Kamlet and Taft. This analysis indicated that both interactions play an important role in the position of the absorption maxima in neat solvents. The simulated absorption spectra of TMP and TMP:(solvent)n complexes in ACN and H2O using TD-DFT methods were in agreement with the experimental ones. Binary aqueous mixtures containing as co-solvents DMSO, ACN and EtOH were studied. Preferential solvation was detected as a nonideal behavior of the wavenumber curve respective to the analytical mole fraction of co-solvent in all binary systems. TMP molecules were preferentially solvated by the organic solvent over the whole composition range. Index of preferential solvation, as well as the influence of solvent parameters were calculated as a function of solvent composition.

  1. TelCoVis: Visual Exploration of Co-occurrence in Urban Human Mobility Based on Telco Data.

    Science.gov (United States)

    Wu, Wenchao; Xu, Jiayi; Zeng, Haipeng; Zheng, Yixian; Qu, Huamin; Ni, Bing; Yuan, Mingxuan; Ni, Lionel M

    2016-01-01

    Understanding co-occurrence in urban human mobility (i.e. people from two regions visit an urban place during the same time span) is of great value in a variety of applications, such as urban planning, business intelligence, social behavior analysis, as well as containing contagious diseases. In recent years, the widespread use of mobile phones brings an unprecedented opportunity to capture large-scale and fine-grained data to study co-occurrence in human mobility. However, due to the lack of systematic and efficient methods, it is challenging for analysts to carry out in-depth analyses and extract valuable information. In this paper, we present TelCoVis, an interactive visual analytics system, which helps analysts leverage their domain knowledge to gain insight into the co-occurrence in urban human mobility based on telco data. Our system integrates visualization techniques with new designs and combines them in a novel way to enhance analysts' perception for a comprehensive exploration. In addition, we propose to study the correlations in co-occurrence (i.e. people from multiple regions visit different places during the same time span) by means of biclustering techniques that allow analysts to better explore coordinated relationships among different regions and identify interesting patterns. The case studies based on a real-world dataset and interviews with domain experts have demonstrated the effectiveness of our system in gaining insights into co-occurrence and facilitating various analytical tasks.

  2. The ammonoids from the Argiles de Timimoun of Timimoun (Early and Middle Viséan; Gourara, Algeria

    Directory of Open Access Journals (Sweden)

    J. Bockwinkel

    2010-02-01

    Full Text Available Twenty-seven ammonoid species are described from the Argiles de Timimoun of Timimoun (Gourara, Algeria. The following taxa are newly described: Rhnetites n. gen., Rhnetites rhnetensis n. sp., Rhnetites ouladallalensis n. sp., Parahammatocyclus mutaris n. sp., Bollandoceras nitens n. sp., Bollandoceras subangulare n. sp., Bollandoceras politum n. sp., Bollandoceras aridum n. sp., Bollandoceras zuhara n. sp., Bollandoceras mirrih n. sp., Benimehlalites n. gen., Benimehlalites benimehlalensis n. sp., Benimehlalites belkassemensis n. sp., Benimehlalites brinkmanni n. sp., Pachybollandoceras n. gen., Pachybollandoceras intraevolutum n. sp., Pachybollandoceras repens n. sp., Bollanditinae n. subfam., Gourarites n. gen., Gourarites hagaraswad n. sp., Gourarites hagarkarim n. sp., Gourarites mustari n. sp., Gourarites zuhal n. sp., Semibollandites n. gen., Semibollandites kamil n. sp., Semibollandites pauculus n. sp., Semibollandites qawiy n. sp., Timimounia n. gen., Timimounia timimounensis n. sp., Timimounia lunula n. sp., Daaitidae n. fam., Daaites n. gen., Daaites daaensis n. sp., Dimorphoceras lanceolobatum n. sp., Nomismoceras salim n. sp., and Nomismoceras waltoni n. sp. The species occur in three successive horizons and can be attributed to the Bollandites-Bollandoceras Genus Zone (Early and Middle Viséan. They represent the most diverse ammonoid fauna known from this time interval. doi:10.1002/mmng.200900013

  3. Simultaneous UV-Vis spectrophotometric quantification of ternary basic dye mixtures by partial least squares and artificial neural networks.

    Science.gov (United States)

    Hassaninejad-Darzi, Seyed Karim; Torkamanzadeh, Mohammad

    2016-11-01

    One of the main difficulties in quantification of dyes in industrial wastewaters is the fact that dyes are usually in complex mixtures rather than being pure. Here we report the development of two rapid and powerful methods, partial least squares (PLS-1) and artificial neural network (ANN), for spectral resolution of a highly overlapping ternary dye system in the presence of interferences. To this end, Crystal Violet (CV), Malachite Green (MG) and Methylene Blue (MB) were selected as three model dyes whose UV-Vis absorption spectra highly overlap each other. After calibration, both prediction models were validated through testing with an independent spectra-concentration dataset, in which high correlation coefficients (R 2 ) of 0.998, 0.999 and 0.999 were obtained by PLS-1 and 0.997, 0.999 and 0.999 were obtained by ANN for CV, MG and MB, respectively. Having shown a relative error of prediction of less than 3% for all the dyes tested, both PLS-1 and ANN models were found to be highly accurate in simultaneous determination of dyes in pure aqueous samples. Using net-analyte signal concept, the quantitative determination of dyes spiked in seawater samples was carried out successfully by PLS-1 with satisfactory recoveries (90-101%).

  4. Simple and Selective HPLC-UV/Vis Bioanalytical Method to Determine Aluminum Phthalocyanine Chloride in Skin Permeation Studies

    Directory of Open Access Journals (Sweden)

    Thaiene Avila Reis

    2018-01-01

    Full Text Available Considering the feasibility of the aluminum phthalocyanine chloride (AlPcCl application in the topical photodynamic therapy of cutaneous tumors and the lack of HPLC methods capable of supporting skin permeation experiments using this compound, the aim of this study was to obtain a simple and selective chromatographic method for AlPcCl determination in skin matrices. A HPLC-UV/Vis method was developed using a normal-phase column operating at 30°C, an isocratic mobile phase of methanol : phosphoric acid (0.01 M at 1.5 mL/min, and detection at 670 nm. The method exhibited (i selectivity against various contaminants found in the different skin layers, (ii high drug extraction capacity from the hair follicle (>70% and remaining skin (>80%, and (iii low limits of detection and of quantification (0.03 and 0.09 μg/mL, resp.. The method was also linear in the range from 0.1 to 5.0 µg/mL (r = 0.9994 and demonstrated robustness with regard to experimental chromatographic parameters according to a factorial design. Lastly, the developed method was successfully tested in in vitro skin permeation studies of AlPcCl, proving its effectiveness in the development of pharmaceutical delivery systems containing this drug for topical photodynamic therapy of skin cancers.

  5. Chlorine Dioxide-Iodide-Methyl Acetoacetate Oscillation Reaction Investigated by UV-Vis and Online FTIR Spectrophotometric Method

    Directory of Open Access Journals (Sweden)

    Laishun Shi

    2012-01-01

    Full Text Available In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide-iodide ion-methyl acetoacetate reaction system, a series of experiments were done by using UV-Vis and online FTIR spectrophotometric method. The initial concentrations of methyl acetoacetate, chlorine dioxide, potassium iodide, and sulfuric acid and the pH value have great influence on the oscillation observed at wavelength of 289 nm. There is a preoscillatory or induction period, and the amplitude and the number of oscillations are associated with the initial concentration of reactants. The equations for the triiodide ion reaction rate changing with reaction time and the initial concentrations in the oscillation stage were obtained. Oscillation reaction can be accelerated by increasing temperature. The apparent activation energies in terms of the induction period and the oscillation period were 26.02 KJ/mol and 17.65 KJ/mol, respectively. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

  6. Living matter observations with a novel hyperspectral supercontinuum confocal microscope for VIS to near-IR reflectance spectroscopy.

    Science.gov (United States)

    Bertani, Francesca R; Ferrari, Luisa; Mussi, Valentina; Botti, Elisabetta; Costanzo, Antonio; Selci, Stefano

    2013-10-25

    A broad range hyper-spectroscopic microscope fed by a supercontinuum laser source and equipped with an almost achromatic optical layout is illustrated with detailed explanations of the design, implementation and data. The real novelty of this instrument, a confocal spectroscopic microscope capable of recording high resolution reflectance data in the VIS-IR spectral range from about 500 nm to 2.5 μm wavelengths, is the possibility of acquiring spectral data at every physical point as defined by lateral coordinates, X and Y, as well as at a depth coordinate, Z, as obtained by the confocal optical sectioning advantage. With this apparatus we collect each single scanning point as a whole spectrum by combining two linear spectral detector arrays, one CCD for the visible range, and one InGaAs infrared array, simultaneously available at the sensor output channel of the home made instrument. This microscope has been developed for biomedical analysis of human skin and other similar applications. Results are shown illustrating the technical performances of the instrument and the capability in extracting information about the composition and the structure of different parts or compartments in biological samples as well as in solid statematter. A complete spectroscopic fingerprinting of samples at microscopic level is shown possible by using statistical analysis on raw data or analytical reflectance models based on Abelés matrix transfer methods.

  7. A portable nondestructive real-time detection system for inspection of pork quality attributes using Vis/NIR spectral technique

    Science.gov (United States)

    Sun, Hongwei; Peng, Yankun

    2016-05-01

    There are many preferences expressing the quality of pork: color, pH, especially TVB-N content. Different quality pork has different spectral feature (in range of 400 to 1000nm). To detect quality attributes of pork easily, real-time, nondestructively, a portable device based on Vis/NIR spectral technique was developed. The device is mainly made up of four units: light source, spectrometer, controller and display screen. After hardware platform established, reflectance spectra of 44 samples were collected from this system. And their physicochemical characteristics such as color parameters, pH value and the content of total volatile basic-nitrogen (TVB-N) were measured in standard methods. Spectrum data acquired were processed by Savitzky-Golay filter(S-G) for noise removal, and then operated by standard normal variable transformation (SNV) for baseline drifts relieving. The partial least squares regression (PLSR) was used to build prediction models for L*, a*, b* pH* and TVB-N content, which could gain good prediction results with Rp of 0.92, 0.91, 0.92, 0.95 and 0.96 respectively. The results demonstrated that this device could be a promising tool applied to detecting pork quality attributes portably, real-time and nondestructively.

  8. Determination of cmc of imidazolium based surface active ionic liquids through probe-less UV-vis spectrophotometry.

    Science.gov (United States)

    Rather, Mudasir Ahmad; Rather, Ghulam Mohammad; Pandit, Sarwar Ahmad; Bhat, Sajad Ahmad; Bhat, Mohsin Ahmad

    2015-01-01

    In the first of its kind we herein report the results of our studies undertaken on the micellization behaviour of imidazolium based surface active ionic liquids (SAILs) to prove that their critical micelle concentration (cmc) can be estimated through ultraviolet-visible (UV-vis) spectroscopy without using any external probe. Tensiometric and spectrophotometric investigations of a series of freshly prepared SAILs viz. 1-octyl-3-methylimidazolium chloride ([OMIM][Cl]), 1-octyl-3-methylimidazolium dodecylsulphate ([OMIM][DS]), 1-octyl-3-methylimidazolium benzoate ([OMIM][Bz]), 1-octyl-3-methylimidazolium salicylate ([OMIM][Sc]), 1-octyl-3-methylimidazolium acetate ([OMIM][Ac]) are presented as a case study in support of the said claim. The cmcs estimated through spectrophotometric method were found to be close to the values estimated through tensiometry for the said SAILs. The cmcs for the investigated SAILS were found to vary in order of [OMIM][Cl]>[OMIM][Ac]>[OMIM][Bz]>[OMIM][Sc]>[OMIM][DS]. To the best of our knowledge the present communication will be the first report about the synthesis, characterization and micellization behaviour of [OMIM][Bz] and [OMIM][Sc]. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Host-Guest Inclusion Complexation of α-Cyclodextrin and Triiodide Examined Using UV-Vis Spectrophotometry.

    Science.gov (United States)

    Pursell, Janet L; Pursell, Christopher J

    2016-04-07

    The historically relevant host-guest complexation of α-cyclodextrin (α-CD) and triiodide (I3(-)) in aqueous solution was examined using a systematic UV-vis spectrophotometric approach. This particular system is experimentally challenging because of the coupled equilibria, namely, I2 + I(-) ⇌ I3(-) and α-CD + I3(-) ⇌ α-CD·I3(-). We therefore developed a unique experimental approach that allowed us to determine the concentration of all iodine species. This enabled us to unequivocally demonstrate that the large increase in the UV absorbance with added α-cyclodextrin is due to an increase in the overall triiodide concentration as α-CD essentially converts iodine to triiodide according to the coupled equilibria. Herein we report (a) the complexation stoichiometry is 1:1 (i.e., the host-guest complex is α-CD·I3(-)), (b) the binding constant is KH-G = (1.35 ± 0.05) × 10(5) M(-1) at room temperature, and (c) the binding constant is temperature dependent with ΔH = -31.0 ± 0.9 kJ/mol.

  10. In situ, rapid, and temporally resolved measurements of cellulase adsorption onto lignocellulosic substrates by UV-vis spectrophotometry.

    Science.gov (United States)

    Liu, Hao; Zhu, J Y; Chai, X S

    2011-01-04

    This study demonstrated two in situ UV-vis spectrophotometric methods for rapid and temporally resolved measurements of cellulase adsorption onto cellulosic and lignocellulosic substrates during enzymatic hydrolysis. The cellulase protein absorption peak at 280 nm was used for quantification. The spectral interferences from light scattering by small fibers (fines) and particulates and from absorptions by lignin leached from lignocelluloses were corrected using a dual-wavelength technique. Wavelengths of 500 and 255 nm were used as secondary wavelengths for correcting spectral interferences from light scattering and absorption of leached lignin. Spectral interferences can also be eliminated by taking the second derivative of the measured spectra of enzymatic hydrolysate of cellulose or lignocelluloses. The in situ measured cellulase adsorptions in cellulose and lignocellulose suspensions by these two spectrophotometric methods showed general agreement with batch sampling assayed by the Bradford method. The in situ methods not only eliminated tedious batch sampling but also can resolve the kinetics of the initial adsorption process. The measured time-dependent cellulase adsorptions were found to follow pseudo-second-order kinetics.

  11. Standardization of fluorescence measurements in the UV/vis/NIR/IR: needs for and requirements on calibration tools (Conference Presentation)

    Science.gov (United States)

    Resch-Genger, Ute; Pauli, Jutta; Hoffmann, Katrin; Würth, Christian; Behnke, Thomas

    2017-02-01

    Photoluminescence techniques are amongst the most widely used tools in the life sciences, with new and exciting applications in medical diagnostics and molecular imaging continuously emerging. Advantages include their comparative ease of use, unique sensitivity, non-invasive character, and potential for multiplexing, remote sensing, and miniaturization. General drawbacks are, however, signals, that contain unwanted wavelength- and polarization contributions from instrument-dependent effects, which are also time-dependent due to aging of instrument-components, and difficulties to measure absolute fluorescence intensities [1]. Moreover, scattering systems require special measurement geometries [2] and the interest in new optical reporters with emission > 1000 nm strategies for reliable measurements in the second diagnostic for the comparison of material performance and the rational design of new fluorophores with improved properties [3]. Here, we present strategies to versatile method-adaptable liquid and solid fluorescence standards for different fluorescence parameters including traceable instrument calibration procedures and the design of integrating sphere setups for the absolute measurement of emission spectra and quantum yields in the wavelength region of 350 to 1600 nm [4,5]. Examples are multi-emitter glasses, spectral fluorescence standards, and quantum yield standards for the UV/vis/NIR.

  12. Fluorescence Lifetime and UV-Vis Spectroscopy to Evaluate the Interactions Between Quercetin and Its Yeast Microcapsule.

    Science.gov (United States)

    Pham-Hoang, Bao-Ngoc; Winckler, Pascale; Waché, Yves

    2017-09-09

    Quercetin is a fragile bioactive compound. Several works have tried to preserve it by encapsulation but the form of encapsulation (mono- or supra-molecular structure, tautomeric form), though important for stability and bioavailability, remains unknown. The present work aims at developing a fluorescence lifetime technique to evaluate the structure of quercetin during encapsulation in a vector capsule that has already proven efficiency, yeast cells. Molecular stabilization was observed during a 4-month storage period. The time-correlated single-photon counting (TCSPC) technique was used to evaluate the interaction between quercetin molecules and the yeast capsule. The various tautomeric forms, as identified by UV-Vis spectroscopy, result in various lifetimes in TCSPC, although they varied also with the buffer environment. Quercetin in buffer exhibited a three-to-four longer long-time after 24 h (changing from 6-7 to 18-23 ns), suggesting an aggregation of molecules. In yeast microcapsules, the long-time population exhibited a longer lifetime (around 27 ns) from the beginning and concerned about 20% of molecules compared to dispersed quercetin. This shows that lifetime analysis can show the monomolecular instability of quercetin in buffer and the presence of interactions between quercetin molecules and their microcapsules. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Identification of different species of Bacillus isolated from Nisargruna Biogas Plant by FTIR, UV-Vis and NIR spectroscopy.

    Science.gov (United States)

    Ghosh, S B; Bhattacharya, K; Nayak, S; Mukherjee, P; Salaskar, D; Kale, S P

    2015-09-05

    Definitive identification of microorganisms, including pathogenic and non-pathogenic bacteria, is extremely important for a wide variety of applications including food safety, environmental studies, bio-terrorism threats, microbial forensics, criminal investigations and above all disease diagnosis. Although extremely powerful techniques such as those based on PCR and microarrays exist, they require sophisticated laboratory facilities along with elaborate sample preparation by trained researchers. Among different spectroscopic techniques, FTIR was used in the 1980s and 90s for bacterial identification. In the present study five species of Bacillus were isolated from the aerobic predigester chamber of Nisargruna Biogas Plant (NBP) and were identified to the species level by biochemical and molecular biological (16S ribosomal DNA sequence) methods. Those organisms were further checked by solid state spectroscopic absorbance measurements using a wide range of electromagnetic radiation (wavelength 200 nm to 25,000 nm) encompassing UV, visible, near Infrared and Infrared regions. UV-Vis and NIR spectroscopy was performed on dried bacterial cell suspension on silicon wafer in specular mode while FTIR was performed on KBr pellets containing the bacterial cells. Consistent and reproducible species specific spectra were obtained and sensitivity up to a level of 1000 cells was observed in FTIR with a DTGS detector. This clearly shows the potential of solid state spectroscopic techniques for simple, easy to implement, reliable and sensitive detection of bacteria from environmental samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Spectral analysis, vibrational assignments, NBO analysis, NMR, UV-Vis, hyperpolarizability analysis of 2-aminofluorene by density functional theory.

    Science.gov (United States)

    Jone Pradeepa, S; Sundaraganesan, N

    2014-05-05

    In this present investigation, the collective experimental and theoretical study on molecular structure, vibrational analysis and NBO analysis has been reported for 2-aminofluorene. FT-IR spectrum was recorded in the range 4000-400 cm(-1). FT-Raman spectrum was recorded in the range 4000-50 cm(-1). The molecular geometry, vibrational spectra, and natural bond orbital analysis (NBO) were calculated for 2-aminofluorene using Density Functional Theory (DFT) based on B3LYP/6-31G(d,p) model chemistry. (13)C and (1)H NMR chemical shifts of 2-aminofluorene were calculated using GIAO method. The computed vibrational and NMR spectra were compared with the experimental results. The total energy distribution (TED) was derived to deepen the understanding of different modes of vibrations contributed by respective wavenumber. The experimental UV-Vis spectra was recorded in the region of 400-200 nm and correlated with simulated spectra by suitably solvated B3LYP/6-31G(d,p) model. The HOMO-LUMO energies were measured with time dependent DFT approach. The nonlinearity of the title compound was confirmed by hyperpolarizabilty examination. Using theoretical calculation Molecular Electrostatic Potential (MEP) was investigated. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Ozone ProfilE Retrieval Algorithm (OPERA for nadir-looking satellite instruments in the UV–VIS

    Directory of Open Access Journals (Sweden)

    J. C. A. van Peet

    2014-03-01

    Full Text Available For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA has been further developed. The new version (1.26 of OPERA is capable of retrieving ozone profiles from UV–VIS observations of most nadir-looking satellite instruments like GOME, SCIAMACHY, OMI and GOME-2. The setup of OPERA is described and results are presented for GOME and GOME-2 observations. The retrieved ozone profiles are globally compared to ozone sondes for the years 1997 and 2008. Relative differences between GOME/GOME-2 and ozone sondes are within the limits as specified by the user requirements from the Climate Change Initiative (CCI programme of ESA (20% in the troposphere, 15% in the stratosphere. To demonstrate the performance of the algorithm under extreme circumstances, the 2009 Antarctic ozone hole season was investigated in more detail using GOME-2 ozone profiles and lidar data, which showed an unusual persistence of the vortex over the Río Gallegos observing station (51° S, 69.3° W. By applying OPERA to multiple instruments, a time series of ozone profiles from 1996 to 2013 from a single robust algorithm can be created.

  16. UV-Vis spectroscopic study and DFT calculation on the solvent effect of trimethoprim in neat solvents and aqueous mixtures.

    Science.gov (United States)

    Almandoz, M C; Sancho, M I; Duchowicz, P R; Blanco, S E

    2014-08-14

    The solvatochromic behavior of trimethoprim (TMP) was analyzed using UV-Vis spectroscopy and DFT methods in neat and binary aqueous solvent mixtures. The effects of solvent dipolarity/polarizability and solvent-solute hydrogen bonding interactions on the absorption maxima were evaluated by means of the linear solvation energy relationship concept of Kamlet and Taft. This analysis indicated that both interactions play an important role in the position of the absorption maxima in neat solvents. The simulated absorption spectra of TMP and TMP:(solvent)n complexes in ACN and H2O using TD-DFT methods were in agreement with the experimental ones. Binary aqueous mixtures containing as co-solvents DMSO, ACN and EtOH were studied. Preferential solvation was detected as a nonideal behavior of the wavenumber curve respective to the analytical mole fraction of co-solvent in all binary systems. TMP molecules were preferentially solvated by the organic solvent over the whole composition range. Index of preferential solvation, as well as the influence of solvent parameters were calculated as a function of solvent composition. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Evaluation of electrochemical, UV/VIS and Raman spectroelectrochemical detection of Naratriptan with screen-printed electrodes.

    Science.gov (United States)

    Hernández, Carla Navarro; Martín-Yerga, Daniel; González-García, María Begoña; Hernández-Santos, David; Fanjul-Bolado, Pablo

    2018-02-01

    Naratriptan, active pharmaceutical ingredient with antimigraine activity was electrochemically detected in untreated screen-printed carbon electrodes (SPCEs). Cyclic voltammetry and differential pulse voltammetry were used to carry out quantitative analysis of this molecule (in a Britton-Robinson buffer solution at pH 3.0) through its irreversible oxidation (diffusion controlled) at a potential of +0.75V (vs. Ag pseudoreference electrode). Naratriptan oxidation product is an indole based dimer with a yellowish colour (maximum absorption at 320nm) so UV-VIS spectroelectrochemistry technique was used for the very first time as an in situ characterization and quantification technique for this molecule. A reflection configuration approach allowed its measurement over the untreated carbon based electrode. Finally, time resolved Raman Spectroelectrochemistry is used as a powerful technique to carry out qualitative and quantitative analysis of Naratriptan. Electrochemically treated silver screen-printed electrodes are shown as easy to use and cost-effective SERS substrates for the analysis of Naratriptan. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Raman, IR, UV-vis and EPR characterization of two copper dioxolene complexes derived from L-dopa and dopamine.

    Science.gov (United States)

    Barreto, Wagner J; Barreto, Sônia R G; Ando, Rômulo A; Santos, Paulo S; DiMauro, Eduardo; Jorge, Thiago

    2008-12-15

    The anionic complexes [Cu(L(1-))3](1-), L(-)=dopasemiquinone or L-dopasemiquinone, were prepared and characterized. The complexes are stable in aqueous solution showing intense absorption bands at ca. 605 nm for Cu(II)-L-dopasemiquinone and at ca. 595 nm for Cu(II)-dopasemiquinone in the UV-vis spectra, that can be assigned to intraligand transitions. Noradrenaline and adrenaline, under the same reaction conditions, did not yield Cu-complexes, despite the bands in the UV region showing that noradrenaline and adrenaline were oxidized during the process. The complexes display a resonance Raman effect, and the most enhanced bands involve ring modes and particularly the nuCC+nuCO stretching mode at ca. 1384 cm(-1). The free radical nature of the ligands and the oxidation state of the Cu(II) were confirmed by the EPR spectra that display absorptions assigned to organic radicals with g=2.0005 and g=2.0923, and for Cu(II) with g=2.008 and g=2.0897 for L-dopasemiquinone and dopasemiquinone, respectively. The possibility that dopamine and L-dopa can form stable and aqueous-soluble copper complexes at neutral pH, whereas noradrenaline and adrenaline cannot, may be important in understanding how Cu(II)-dopamine crosses the cellular membrane as proposed in the literature to explain the role of copper in Wilson disease.

  19. Synthesis, characterization, and UV-vis linear absorption of centrosymmetric pi-systems incorporating closo-dodecaborate clusters.

    Science.gov (United States)

    Bernard, Rémy; Cornu, David; Scharff, Jean-Pierre; Chiriac, Rodica; Miele, Philippe; Baldeck, Patrice L; Caslavský, Josef

    2006-10-16

    Single- and multibranched centrosymmetric derivatives incorporating B12 clusters [B12H11-N(H)=C(H)-C6H4-C6H4-C(H)=(H)N-B12H11]2- (3) and [1,3,5-(4-(B12H11-N(H)=C(H))-C6H4)-C6H3]3- (5) have been synthesized. Both derivatives were characterized by multinuclear NMR and ESI-MS analyses. To the best of our knowledge, compound 5 is the first example of a multicage derivative bearing three B12 units. Compounds 3 and 5 are only slightly yellowish colored. The UV-vis absorption curves of 3 and 5 show intense absorption bands at 360 and 314 nm, respectively. This result permits us to confirm the strong donor effect of the B12 cluster. The hypsochrome effect observed for compound 5 compared to that of compound 3 confirms the interest in multibranched derivatives for the preparation of two-photon absorption materials active in the visible range.

  20. Phytochemical Composition and Antioxidant Activities of the Essential Oil and Extracts of Satureja subspicata Vis. Growing in Bosnia and Herzegovina.

    Science.gov (United States)

    Bektašević, Mejra; Carev, Ivana; Roje, Marin; Jurin, Mladenka; Politeo, Olivera

    2017-10-01

    The phytochemical composition and the antioxidant activities of the essential oil, as well as methanol and hot water extracts of endemic Satureja subspicata Vis. growing in Bosnia and Herzegovina (BiH), were described. β-Caryophyllene, cis-β-ocimene, and α-pinene, identified by GC/MS and GC-FID, were the dominant oil components. The major compound of both of extracts, identified by HPLC-DAD, was rosmarinic acid. The analyzed essential oil showed moderate antioxidant activity. In this first report on the extracts of S. subspicata growing in BiH, the obtained results showed a high content of rosmarinic acid, as well as considerable amount of total phenols and flavonoids. Compared to the hot water extract, the methanol extract exhibits higher antioxidant potential, measured by DPPH and FRAP assay (IC 50 = 0.45 g/l and 1879.43 equiv. Fe 2+ μm), while the hot water extract showed higher potential in inhibition of linoleic acid oxidation (51.7% and 61.5% for 1 and 10 g/l). A good antioxidant potential of the tested extracts indicates their potential use as antioxidants, particularly for lipid protection, and partly explains the justification of the use of this plant in traditional medicine of BiH. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  1. Identification of different species of Bacillus isolated from Nisargruna Biogas Plant by FTIR, UV-Vis and NIR spectroscopy

    Science.gov (United States)

    Ghosh, S. B.; Bhattacharya, K.; Nayak, S.; Mukherjee, P.; Salaskar, D.; Kale, S. P.

    2015-09-01

    Definitive identification of microorganisms, including pathogenic and non-pathogenic bacteria, is extremely important for a wide variety of applications including food safety, environmental studies, bio-terrorism threats, microbial forensics, criminal investigations and above all disease diagnosis. Although extremely powerful techniques such as those based on PCR and microarrays exist, they require sophisticated laboratory facilities along with elaborate sample preparation by trained researchers. Among different spectroscopic techniques, FTIR was used in the 1980s and 90s for bacterial identification. In the present study five species of Bacillus were isolated from the aerobic predigester chamber of Nisargruna Biogas Plant (NBP) and were identified to the species level by biochemical and molecular biological (16S ribosomal DNA sequence) methods. Those organisms were further checked by solid state spectroscopic absorbance measurements using a wide range of electromagnetic radiation (wavelength 200 nm to 25,000 nm) encompassing UV, visible, near Infrared and Infrared regions. UV-Vis and NIR spectroscopy was performed on dried bacterial cell suspension on silicon wafer in specular mode while FTIR was performed on KBr pellets containing the bacterial cells. Consistent and reproducible species specific spectra were obtained and sensitivity up to a level of 1000 cells was observed in FTIR with a DTGS detector. This clearly shows the potential of solid state spectroscopic techniques for simple, easy to implement, reliable and sensitive detection of bacteria from environmental samples.

  2. Effect of Soil Use and Coverage on the Spectral Response of an Oxisol in the VIS-NIR-MIR Region

    Directory of Open Access Journals (Sweden)

    Javier M. Martín-López

    2017-02-01

    Full Text Available In this study, the spectral responses obtained from a Typic Red Hapludox (oxisol were analyzed under different uses and occupations: Ficus elastica cultivation, Citrus + Arachis association cultivation, transitional crops, forest, Mangifera indica, Anacardium occidentale, Elaeis guineensis (18 years, Brachiaria decumbens, Brachiaria brizantha, and Musa × paradisiaca + Zea mays at the La Libertad Research Center in the department of Meta in Colombia (4°04′ North latitude, 73°30′ West longitude, 330 MAMSL. Sampling was performed with four random replicates of the horizon A and B to determine the contents of organic carbon (CO, pH, exchangeable acidity (Ac. I, cation exchange capacity (Cc, P, Ca, Mg, K, Na, sand, lime, and clay and spectral responses were obtained in the visible band (VIS, near infrared (NIR, and infrared (MIR for each sample under laboratory conditions. A comparison was made between the obtained spectra, determining the main changes in soil properties due to their use and coverage. Variation of soil characteristics such as color, organic carbon content, presence of ferrous compounds, sand, silt, and clay content and mineralogy allow the identification of the main spectral changes of soils, demonstrating the importance of the use of reflectance spectroscopy as a tool of comparison and estimation between physical-chemical properties of the soils.

  3. Exploring the limits of morphospace: Ontogeny and ecology of late Viséan ammonoids from the Tafilalt, Morocco

    Directory of Open Access Journals (Sweden)

    Christian Klug

    2016-02-01

    Full Text Available Early late Viséan ammonoid assemblages in Morocco are composed of diverse and well-preserved specimens. The material was found in a plain in the Tafilalt (eastern Anti-Atlas. Here, we describe mass-occurrences of juvenile specimens, in which subadult and adult specimens occur in low numbers. The juveniles of some species display a conch morphology that differs fundamentally from the adult stages. Accordingly, we emend the species diagnoses of Goniatites lazarus as well as Calygirtyoceras darkaouaense, introduce the species Entogonites bucheri sp. nov., and discuss possible ecological implications of the morphologic changes throughout ontogeny. In particular, we compare the changes in conch morphology through ontogeny in the light of Pareto Optimiality according to which the morphology of organisms would fill a polygon or polyhedron in morphospace. Data points in one of the vorteces of the polyhedron indicate optimisation for the corresponding task. Although shape is not a proof of function, it appears plausible that juvenile conchs were selected rather for compactness while adult conchs were positively selected for conchs with improved hydrodynamic properties. This appears plausible because at small conch diameters, swimming movements will not suffice for effective translocation and a planktonic mode of life is likely.

  4. Theoretical Calculation of the Uv-Vis Spectral Band Locations of Pahs with Unknown Syntheses Procedures and Prospective Carcinogenic Activity

    Science.gov (United States)

    Ona-Ruales, Jorge Oswaldo; Ruiz-Morales, Yosadara

    2017-06-01

    Annellation Theory and ZINDO/S semiempirical calculations have been used for the calculation of the locations of maximum absorbance (LMA) of the Ultraviolet-Visible (UV-Vis) of 31 C_{34}H_{16} PAHs (molecular mass 424 Da) with unknown protocols of synthesis. The presence of benzo[a]pyrene bay-like regions and dibenzo[a,l]pyrene fjord-like regions in several of the structures that could be linked to an enhancement of the biological behavior and carcinogenic activity stresses the importance of C_{34}H_{16} PAHs in fields like molecular biology and cancer research. In addition, the occurrence of large PAHs in oil asphaltenes exemplifies the importance of these calculations for the characterization of complex systems. The C_{34}H_{16} PAH group is the largest molecular mass group of organic compounds analyzed so far following the Annellation Theory and ZINDO/S methodology. Future analysis using the same approach will provide evidence regarding the LMA of other high molecular mass PAHs.

  5. Dimensões psicológicas do aquecimento global conforme a visão de adolescentes brasileiros

    Directory of Open Access Journals (Sweden)

    Hellen Chrystianne Lucio Barros

    2013-06-01

    Full Text Available Evidências científicas sugerem o envolvimento das ações humanas nas mudanças climáticas globais (MCGs - seja como intensificadoras, mitigadoras ou adaptadoras diante dos seus efeitos - situação que evidencia a relevância de se investigar os aspectos psicológicos envolvidos no tema. O objetivo deste estudo foi investigar a visão de adolescentes sobre o aquecimento global (AG, que é uma parte importante das MCGs. Participaram 323 estudantes do Ensino Fundamental e Médio, sendo 202 garotas e 121 rapazes, com idades entre 12 e 19 anos, e média de 15 anos, que responderam a um questionário, contendo uma pergunta aberta sobre AG. Evidenciou-se que o conhecimento do assunto é superficial; os estudantes o percebem como um problema ambiental genérico, e o confundem com outros problemas, como a poluição. A cadeia interdependente de fenômenos relacionados às MCGs, como os gases do efeito estufa, foi mencionada por raríssimos participantes, assim como as implicações locais do problema.

  6. Living Matter Observations with a Novel Hyperspectral Supercontinuum Confocal Microscope for VIS to Near-IR Reflectance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Francesca R. Bertani

    2013-10-01

    Full Text Available A broad range hyper-spectroscopic microscope fed by a supercontinuum laser source and equipped with an almost achromatic optical layout is illustrated with detailed explanations of the design, implementation and data. The real novelty of this instrument, a confocal spectroscopic microscope capable of recording high resolution reflectance data in the VIS-IR spectral range from about 500 nm to 2.5 μm wavelengths, is the possibility of acquiring spectral data at every physical point as defined by lateral coordinates, X and Y, as well as at a depth coordinate, Z, as obtained by the confocal optical sectioning advantage. With this apparatus we collect each single scanning point as a whole spectrum by combining two linear spectral detector arrays, one CCD for the visible range, and one InGaAs infrared array, simultaneously available at the sensor output channel of the home made instrument. This microscope has been developed for biomedical analysis of human skin and other similar applications. Results are shown illustrating the technical performances of the instrument and the capability in extracting information about the composition and the structure of different parts or compartments in biological samples as well as in solid statematter. A complete spectroscopic fingerprinting of samples at microscopic level is shown possible by using statistical analysis on raw data or analytical reflectance models based on Abelés matrix transfer methods.

  7. A new method for the absolute radiance calibration for UV/vis measurements of scattered sun light

    Science.gov (United States)

    Wagner, T.; Beirle, S.; Dörner, S.; Penning de Vries, M.; Remmers, J.; Rozanov, A.; Shaiganfar, R.

    2015-05-01

    Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds and the short wave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV/vis instruments that measure the spectrally resolved sky radiance, like for example zenith sky Differential Optical Absorption Spectroscopy (DOAS-) instruments or Multi-AXis (MAX-) DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method clear sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about ozone column density during the measurements is constant and known.

  8. A Workflow for Simulation and Visualization Of Seismic Wave Propagation Using SeisSol, VisIt and Avizo

    KAUST Repository

    Passone,Luca

    2011-08-01

    Ground motion estimation and subsurface exploration are main research areas in computational seismology, they are fundamental for implementing earthquake engineering requirements and for modern subsurface reservoir assessment. In this study we propose a workflow for discretizing, simulating and visualizing near source ground motion due to earthquake rupture. For data generation we use an elastic wave equation solver called SeisSol based on the Discontinuous Galerkin formulation with Arbitrary high-order DERivatives (ADER-DG). SeisSol is capable of highly accurate treatment of any earthquake source characterization, occurring on geometrically complex fault systems embedded in geologically complicated earth structures. We then visualize the results with two tools: VisIt (“a free interactive parallel visualization and graphical analysis tool for viewing scientific data”) and Avizo (“The 3D Analysis Software for Scientific and Industrial data”). We investigate each approach, include our experiences from model generation to visualization in highly immersive environments and conclude with a set of general recommendations for earthquake visualization.

  9. Transformations of methyl orange dimers in aqueous-acid solutions, according to UV-Vis spectroscopy data

    Science.gov (United States)

    Mikheev, Yu. A.; Guseva, L. N.; Ershov, Yu. A.

    2017-10-01

    The effect acidity has on the UV-Vis absorption spectra of azo dye methyl orange (MOD) in aqueous solutions of hydrochloric acid in the pH range of 1.7 to 7 and sulfuric acid in the 0.24 to 18 mol/L range of concentrations is investigated. The spectral transformations of MOD solutions are compared to the corresponding spectral transformations of solutions of dimethylaminoazobenzene (DAB), which is an azo dye akin to MOD. A close resemblance between the spectral transformations of MOD and dimers DAB2 is revealed. It is concluded that the ground state of MOD, like the ground state of DAB, consists of not individual molecules but of supramolecular dimers MOD2. It is found that dimers MOD2 in aqueous low-acidic solutions are reversibly protonated with the formation of di- and triprotonated forms, which reversibly dissociate into diprotonated monomers upon an increase in acidity. The structural formulas of the chromogenic groups responsible for the spectral transformations, and the mechanisms of their reversible transformations, are given.

  10. UV/VIS spektrofotometrie a možnosti jejího využití v rámci vzdělávání učitelů chemie

    OpenAIRE

    Hejsková, Veronika

    2016-01-01

    This master's thesis discusses the use of UV/VIS spectrophotometry in chemistry teacher education. Optical methods principles are described in theoretical part of the thesis, and. the main part is dedicated to UV-VIS spectrophotometry. Tasks for quantifying and qualifying substances determination are described in experimental part. Educational tasks are described in a way so that chemistry teachers could use for instructions.

  11. Predicting soil properties for sustainable agriculture using vis-NIR spectroscopy: a case study in northern Greece

    Science.gov (United States)

    Tsakiridis, Nikolaos L.; Tziolas, Nikolaos; Dimitrakos, Agathoklis; Galanis, Georgios; Ntonou, Eleftheria; Tsirika, Anastasia; Terzopoulou, Evangelia; Kalopesa, Eleni; Zalidis, George C.

    2017-09-01

    Soil Spectral Libraries facilitate agricultural production taking into account the principles of a low-input sustainable agriculture and provide more valuable knowledge to environmental policy makers, enabling improved decision making and effective management of natural resources in the region. In this paper, a comparison in the predictive performance of two state of the art algorithms, one linear (Partial Least Squares Regression) and one non-linear (Cubist), employed in soil spectroscopy is conducted. The comparison was carried out in a regional Soil Spectral Library developed in the Eastern Macedonia and Thrace region of Northern Greece, comprised of roughly 450 Entisol soil samples from soil horizons A (0-30 cm) and B (30-60 cm). The soil spectra were acquired in the visible - Near Infrared Red region (vis- NIR, 350nm-2500nm) using a standard protocol in the laboratory. Three soil properties, which are essential for agriculture, were analyzed and taken into account for the comparison. These were the Organic Matter, the Clay content and the concentration of nitrate-N. Additionally, three different spectral pre-processing techniques were utilized, namely the continuum removal, the absorbance transformation, and the first derivative. Following the removal of outliers using the Mahalanobis distance in the first 5 principal components of the spectra (accounting for 99.8% of the variance), a five-fold cross-validation experiment was considered for all 12 datasets. Statistical comparisons were conducted on the results, which indicate that the Cubist algorithm outperforms PLSR, while the most informative transformation is the first derivative.

  12. A atualidade da visão de Ab’Sáber / The current view of Ab’Sáber

    Directory of Open Access Journals (Sweden)

    Claudio Antonio Di Mauro

    2012-04-01

    Full Text Available A produção científica⃰ pela lavra do Professor Aziz Nacib Ab´Sáber é revisitada em, pelo menos, três aspectos considerados fundamentais: 1 a geomorfologia e a evolução paleoclimática no terciário e quaternário, quando o autor reconhece que os estudos de fisiologia de paisagens, ainda que essenciais para os objetivos dos geomorfologistas, somente podem ser esclarecidos à custa de pesquisas marcadamente interdisciplinares; 2 as mudanças climáticas em processos, que são ignoradas nos conhecimentos sobre o presente, e as heranças obtidas ao longo da história do Planeta Terra, para planejar, com cuidados, as ações que as sociedades promoveriam em busca do “desenvolvimento”; 3 o sítio urbano de São Paulo, em meados do século passado, quando, em menos de 15 anos, a cidade que nasceu e cresceu sobre colinas, e que elegeu as colinas como seu tipo ideal de sítio topográfico, desceu para as várzeas, ocupando setores e glebas importantes das planícies recém enxugadas pelas obras da Companhia Light. As contribuições, inicialmente elaboradas sob a perspectiva geomorfológica, tinham, em suas essências, a visão geográfica do cidadão do mundo.

  13. [Study on photocatalytic decomposition of azo-dyes by ZnO/carbon nanotubes composites by UV-Vis spectroscopy].

    Science.gov (United States)

    Xu, Jing; Song, Xiao-jie; Wei, Xian-wen

    2007-12-01

    ZnO/carbon nanotubes composites were prepared by hydrothermal treatment of the mixture of zinc nitrate and acid-treated multiwalled carbon nanotubes and characterized by transmission electron microscope (TEM) and X-ray powder diffraction (XRD). The TEM image indicated that ZnO nanoparticles with a diameter about 28 nm covered the carbon nanotubes. The XRD pattern shows that ZnO nanoparticles attached to the MWNTs exhibit a hexagonal phase. The diffraction peaks can be assigned to (100), (002), (101), (102), (110), (103), (200), (112) and (201) planes of the crystalline ZnO, respectively. The average size of the crystalline ZnO, calculated from the half-width of the (100) diffraction peak by the Scherrer equation, is 27.8 nm, which accords with the TEM observation. The ZnO/carbon nanotubes composites were used as a photocatalyst under sunlight for the decomposition of azo-dye, which was studied by UV-Vis spectroscopy. The effects of the illumination time, catalyst amount, initial dye concentration and the different structures of the dye on the photocatalytic process were investigated. It was noted that the intensity of the absorption peak corresponding to the azo-dye decreased rapidly at 400 nm during the photolysis process and the decomposition of azo-dye was a quasi-first order reaction. The decomposition rates for azo-dyes such as acid orange, Acid bright red, Acid light yellow are 0.09, 0.28 and 0.22 mg x L(-1) x min(-1), respectively, which maybe resulted from their different functional groups. It can be stated that the complete removal of color, after selection of optimum operation parameters, can be achieved in relatively short time by using ZnO/carbon nanotubes composites. After recycling 5 times, the catalyst still has more than 50% efficiency.

  14. Sobre a identidade profissional na Enfermagem: reconsiderações pontuais em visão filosófica

    Directory of Open Access Journals (Sweden)

    Vilma de Carvalho

    2013-09-01

    Full Text Available Trata-se, neste artigo, de contribuição aos 80 anos da Revista Brasileira de Enfermagem, órgão oficial da Associação Brasileira de Enfermagem (ABEn, antes designado Annaes de Enfermagem e criado em maio de 1932. À época, valeram os propósitos de assegurar a divulgação de assuntos e interesses da Classe Profissional entre os associados, e entre a entidade - Associação Nacional de Enfermeiras Diplomadas Brasileiras (ANEDB - e o público em geral. Assim, impulsionou-se a liderança associativa aliada aos avanços profissionais e à gênese de produções pertinentes ao Saber/Conhecimento, à educação e prática assistencial de Enfermagem. O trabalho foi escrito com abordagem em discussão e apreciação analítica sobre a identidade profissional mirada em reconsiderações pontuais e visão filosófica. Ao invés de protocolos de investigação, a autora se destaca pelo estilo pragmático tomando três exemplos de situações-problema da prática, como eixos para apreciação crítica sobre a arte de enfermeira e definição do perfil profissional na trajetória histórico-evolutiva - com início na modernidade nightingaleana e conceitos advindos de proposições parsonianas -, como referenciados na Enfermagem brasileira. Sem esgotar o assunto, apenas as questões pertinentes são levantadas.

  15. Web-based Data Exploration, Exploitation and Visualization Tools for Satellite Sensor VIS/IR Calibration Applications

    Science.gov (United States)

    Gopalan, A.; Doelling, D. R.; Scarino, B. R.; Chee, T.; Haney, C.; Bhatt, R.

    2016-12-01

    The CERES calibration group at NASA/LaRC has developed and deployed a suite of online data exploration and visualization tools targeted towards a range of spaceborne VIS/IR imager calibration applications for the Earth Science community. These web-based tools are driven by the open-source R (Language for Statistical Computing and Visualization) with a web interface for the user to customize the results according to their application. The tool contains a library of geostationary and sun-synchronous imager spectral response functions (SRF), incoming solar spectra, SCIAMACHY and Hyperion Earth reflected visible hyper-spectral data, and IASI IR hyper-spectral data. The suite of six specific web-based tools was designed to provide critical information necessary for sensor cross-calibration. One of the challenges of sensor cross-calibration is accounting for spectral band differences and may introduce biases if not handled properly. The spectral band adjustment factors (SBAF) are a function of the earth target, atmospheric and cloud conditions or scene type and angular conditions, when obtaining sensor radiance pairs. The SBAF will need to be customized for each inter-calibration target and sensor pair. The advantages of having a community open source tool are: 1) only one archive of SCIAMACHY, Hyperion, and IASI datasets needs to be maintained, which is on the order of 50TB. 2) the framework will allow easy incorporation of new satellite SRFs and hyper-spectral datasets and associated coincident atmospheric and cloud properties, such as PW. 3) web tool or SBAF algorithm improvements or suggestions when incorporated can benefit the community at large. 4) The customization effort is on the user rather than on the host. In this paper we discuss each of these tools in detail and explore the variety of advanced options that can be used to constrain the results along with specific use cases to highlight the value-added by these datasets.

  16. Weed mapping using a machine vision system Mapeamento de plantas daninhas utilizando um sistema de visão artificial

    Directory of Open Access Journals (Sweden)

    M.C. Silva Junior

    2012-03-01

    Full Text Available Weed mapping is a useful tool for site-specific herbicide applications. The objectives of this study were (1 to determine the percentage of land area covered by weeds in no-till and conventionally tilled fields of common bean using digital image processing and geostatistics, and (2 to compare two types of cameras. Two digital cameras (color and infrared and a differential GPS were affixed to a center pivot structure for image acquisition. Sample field images were acquired in a regular grid pattern, and the images were processed to estimate the percentage of weed cover. After calculating the georeferenced weed percentage values, maps were constructed using geostatistical techniques. Based on the results, color images are recommended for mapping the percentage of weed cover in no-till systems, while infrared images are recommended for weed mapping in conventional tillage systems.Mapeamento de plantas daninhas é uma ferramenta útil em aplicações localizadas de herbicidas. Os objetivos deste trabalho foram: determinar o percentual da cobertura vegetal de plantas daninhas em uma lavoura de feijão sob os sistemas de plantio direto e convencional, usando processamento digital de imagens e geoestatística; e comparar dois tipos de câmera. O sistema de visão artificial era composto por duas câmeras digitais (colorida e infravermelha, acopladas à estrutura móvel do pivô central, e um DGPS. As imagens adquiridas representavam amostras da área, em uma malha regular de pontos, e elas foram processadas para estimar a porcentagem da cobertura das plantas daninhas. De posse desses valores georreferenciados, foi possível construir mapas usando técnicas de geoestatística. Com base nos resultados, as imagens coloridas foram as mais adequadas para o mapeamento da cobertura vegetal de plantas daninhas em plantio direto, enquanto as imagens infravermelhas foram mais adequadas para o mapeamento em plantio convencional.

  17. A global view of industrial logistics Uma visão global da logística industrial

    Directory of Open Access Journals (Sweden)

    Lilian Barros

    1997-08-01

    Full Text Available The term "industrial logistics" is a wide-reaching concept which incorporates various forms of supporting activities. In this paper, an attempt is made to provide a definition of the term which is broad enough to incorporate these various views. In a few words, there are three large categories of logistic support: (i product support; (ii production support, and (iii industrial sector support. Although not new as a concept, there has been a recent surge of interest about industrial logistics, for good reasons. One of them might be that the absence of explicit integrated logistic considerations may explain the widening technological gap between the developed and developing worlds.O termo "logística industrial" é um conceito amplo que incorpora várias formas de atividades de suporte. Neste artigo, uma tentativa é feita para fornecer uma definição deste termo, ampla o suficiente para incorporar estas várias visões. Resumidamente, existem três grandes categorias de atividades de suporte logístico: (i suporte de produto; (ii suporte de produção, e (iii suporte do setor industrial. Embora não seja um conceito novo, tem havido um surto recente de interesse em logística industrial, por boas razões. Uma delas poderia ser que a falta de considerações explícitas de logística integrada devem explicar a ampla defasagem tecnológica entre mundos desenvolvidos e em desenvolvimento.

  18. Genesis and properties of wetland soils by VIS-NIR-SWIR as a technique for environmental monitoring.

    Science.gov (United States)

    Demattê, José Alexandre Melo; Horák-Terra, Ingrid; Beirigo, Raphael Moreira; Terra, Fabrício da Silva; Marques, Karina Patrícia Prazeres; Fongaro, Caio Troula; Silva, Alexandre Christófaro; Vidal-Torrado, Pablo

    2017-07-15

    Wetlands are important ecosystems characterized by redoximorphic environments producing typical soil forming processes and organic carbon accumulation. Assessments and management of these areas are dependent on knowledge about soil characteristics and variability. By reflectance spectroscopy, information about soils can be obtained since their spectral behaviors are directly related to their chemical, physical, and mineralogical properties reflecting the pedogenetic processes and environment conditions. Our aims were: (a) to characterize the main soil classes of wetlands regarding their spectral behaviors in VIS-NIR-SWIR (350-2500 nm) and relate them to pedogenesis and environmental conditions, (b) to determine spectral ranges (bands) with greater expression of the main soil properties, (c) to identify spectral variations and similarities between hydromorphic soils from wetlands and other soils under different moisture conditions, and (d) to propose spectral models to quantify some chemical and physical soil properties used as environmental quality indicators. Nine soil profiles from the Pantanal region (Mato Grosso State, Brazil) and one from the Serra do Espinhaço Meridional (Minas Gerais State, Brazil) were investigated. Spectral morphology interpretation allowed identifying horizon differences regarding shape, absorption features and reflectance intensity. Some pedogenetic processes of wetland soils related to organic carbon accumulation and oxide iron variation were identified by spectra. Principal Component Analysis allowed discriminating soils from wetland and outside this area (oxidic environment). Quantification of organic carbon was possible with R 2 of 0.90 and low error. Quantification of clay content was masked by soils with organic carbon content over 2% where it was not possible to quantify with high R 2 and low error both properties when dataset has soil samples with high organic carbon content. By reflectance spectroscopy, important

  19. Interrelating meteorite and asteroid spectra at UV-Vis-NIR wavelengths using novel multiple-scattering methods

    Science.gov (United States)

    Martikainen, Julia; Penttilä, Antti; Gritsevich, Maria; Muinonen, Karri

    2017-10-01

    Asteroids have remained mostly the same for the past 4.5 billion years, and provide us information on the origin, evolution and current state of the Solar System. Asteroids and meteorites can be linked by matching their respective reflectance spectra. This is difficult, because spectral features depend strongly on the surface properties, and meteorite surfaces are free of regolith dust present in asteroids. Furthermore, asteroid surfaces experience space weathering which affects their spectral features.We present a novel simulation framework for assessing the spectral properties of meteorites and asteroids and matching their reflectance spectra. The simulations are carried out by utilizing a light-scattering code that takes inhomogeneous waves into account and simulates light scattering by Gaussian-random-sphere particles large compared to the wavelength of the incident light. The code uses incoherent input and computes phase matrices by utilizing incoherent scattering matrices. Reflectance spectra are modeled by combining olivine, pyroxene, and iron, the most common materials that dominate the spectral features of asteroids and meteorites. Space weathering is taken into account by adding nanoiron into the modeled asteroid spectrum. The complex refractive indices needed for the simulations are obtained from existing databases, or derived using an optimization that utilizes our ray-optics code and the measured spectrum of the material.We demonstrate our approach by applying it to the reflectance spectrum of (4) Vesta and the reflectance spectrum of the Johnstown meteorite measured with the University of Helsinki integrating-sphere UV-Vis-NIR spectrometer.Acknowledgments. The research is funded by the ERC Advanced Grant No. 320773 (SAEMPL).

  20. Compact, integrable, and long life time Raman multiline UV-Vis source based on hypocycloid core Kagome HC-PCF

    Science.gov (United States)

    Chafer, M.; Lekiefs, Q.; Gorse, A.; Beaudou, B.; Debord, B.; Gérôme, F.; Benabid, F.

    2017-02-01

    Raman-gas filled HC-PCF has proved to be an outstanding Raman-convertor, as illustrated by the generation of more than 5 octaves wide Raman comb using a hydrogen-filled Kagome HC-PCF pumped with high power picosecond-laser, or the generation of multiline Raman-source in the UV-Vis using a very compact system pumped with micro-chip laser. Whilst these demonstrations are promising, a principal challenge for the industrialization of such a Raman source is its lifetime as the H2 diffusion through silica is high enough to leak out from the fiber within only a few months. Here, we report on a HC-PCF based Raman multiline source with a very long life-span. The system consists of hydrogen filled ultra-low loss HC-PCF contained in highly sealed box, coined CombBox, and pumped with a 532 nm micro-chip laser. This combination is a turnkey multiline Raman-source with a "shoe box" size. The CombBox is a robust and compact component that can be integrated and pumped with any common pulsed laser. When pumped with a 32 mW average power and 1 ns frequency-doubled Nd:Yag microchip laser, this Raman-source generates 24 lines spanning from 355 to 745 nm, and a peak power density per line of 260 mW/nm for the strongest lines. Both the output power and the spectrum remained constant over its monitoring duration of more than six months. The spectrum of this multiline laser superimposes with no less than 17 absorption peaks of fluorescent dyes from the Alexa Fluor family used as biological markers.

  1. Primeira infância: a visão do Banco Mundial The World Bank's view of early childhood

    Directory of Open Access Journals (Sweden)

    Helen Penn

    2002-03-01

    Full Text Available Este artigo examina a visão do Banco Mundial sobre a primeira infância como exemplo da globalização da infância. Argumenta que a globalização é caracterizada por um ponto de vista econômico neoliberal que exacerba a desigualdade entre nações ricas e pobres e entre ricos e pobres, dentro de cada país, bem como por um otimismo tecnológico-científico que enfatiza os benefícios das intervenções tecnológicas. O artigo mostra como esses dois aspectos da globalização influenciaram as políticas para crianças pequenas que o Banco Mundial vem promovendo ativamente. Recorre aos indícios apresentados pelo Banco Mundial para exemplificar as contradições inerentes a essa abordagem.This paper explores the World Bank's view of early childhood as an example of the globalization of childhood. It argues that globalization is characterized by a particular neo-liberal economic approach which exacerbates the gap between rich and poor nations and between the rich and poor within countries; and by a technological/scientific optimism which stresses the benefits of technological interventions. It traces how these two aspects of globalization have influenced the policies towards young children that the World Bank is now actively promoting. It will draw on evidence presented by the World Bank to illustrate the contradictions inherent in such an approach.

  2. Prediction of SOC content at European scale by coupling Vis-NIR spectroscopy and a modified local PLSR algorithm

    Science.gov (United States)

    Nocita, M.; Stevens, A.; De Brogniez, D.; Bampa, F.; Toth, G.; Panagos, P.; van Wesemael, B.; Montanarella, L.

    2012-04-01

    The spatial variability of soils still represents an important challenge to accurately report the soil status. Visible near infrared soil spectroscopy (VNIRS) has been shown to be an efficient tool for the prediction of soil organic carbon (SOC) at fine scales. However, when applied to regional or country scales, VNIRS did not provide sufficient accuracy as an alternative to standard laboratory soil analysis for SOC monitoring. Under the framework of LUCAS project of the Joint Research Centre (JRC), about 20,000 samples were collected all over European Union. Soil samples were analyzed for several physical and chemical parameters, and scanned with a Vis-NIR spectrometer in the same laboratory. The scope of our research was to predict SOC content at European scale using LUCAS spectral library. We implemented a modified local partial least square regression (l-PLSR) including, in addition to spectral distance, other potentially useful covariates (geography, texture, etc.) to select for each unknown sample a group of k predicting neighbors. The dataset was divided into tuning (15%), training (60%), and validation (25%) subsets. The tuning subset was used to find the most performing combination of model parameters. The best model was then calibrated and validated on training and validation subsets. Although the high variability of land-use systems covered by LUCAS sampling campaign, the chosen methodology resulted in a fair prediction ability (RMSE: 5-6 g C kg-1) at continental scale, but not precise enough to be used for SOC monitoring on a point by point basis. The results indicated that a local approach might improve the ability of VNIRS in predicting SOC trends, with the increasing variability of land managements at larger scales.

  3. Elinor Ostrom, a premiação da visão unificada das ciências humanas

    Directory of Open Access Journals (Sweden)

    Amilcar Baiardi

    Full Text Available Sempre houve preocupações no sentido de estabelecer uma conexão histórica e paradigmática entre a sociologia, a economia e a política, sustentando a unificação dos campos científicos e trazendo de volta aquilo que para Weber era a Ciência Social como "Ciência da Realidade", voltada para a compreensão da significação cultural atual dos fenômenos e para o entendimento de sua origem histórica e que, para Marx, era a busca da totalidade, fundamental porque não seria possível compreender as partes sem uma visão do todo. Neste texto, explora-se esse "approach", focando a obra de Elinor Ostrom, vencedora do Prêmio Nobel de Economia de 2009, que sempre se recusou a ver a esfera das ciências humanas como uma "Torre de Babel", mas sim como um ambiente com amplas possibilidades de integração, sendo sua práxis um exemplo completo e eloquente de convergência e de síntese nas ciências sociais. Após o breve exame de alguns casos emblemáticos de tentativas de integração das ciências sociais, analisam-se a trajetória acadêmica de Elinor Ostrom e suas principais contribuições para as pesquisas sobre os recursos e bens de propriedade comum.

  4. Determination of fatty alcohol ethoxylates by derivatization with phthalic anhydride followed by liquid chromatography with UV-vis detection.

    Science.gov (United States)

    Micó-Tormos, A; Simó-Alfonso, E F; Ramis-Ramos, G

    2008-08-29

    The esterification of fatty alcohol ethoxylates (FAEs) with phthalic anhydride in 1,4-dioxane was studied. At 110 degrees C and in the presence of urea, which increased the reaction rate, esterification was completed in 60 min. The reaction yield did not decrease when the sample contained up to 50% water. For the non-ethoxylated alcohols, the UV-vis response factors of the derivatives were not significantly different from each other (f=1 for C12E0 as reference). The response factors decreased when the number of ethylene oxide units, m, increased, reaching constant values of ca. 0.40 and 0.65 for the n=8 and 18 series, respectively, when m>or=3. Using a C8 column and gradient elution with acetonitrile/water plus 0.1% acetic acid, FAEs in industrial mixtures and cleaning products were characterized. At column temperatures of 25 and 35 degrees C, homologous series with even values of n from 8 up to 20, were resolved up to m=14 and 18, respectively, and at 25 degrees C, series with consecutive even and odd values of n were resolved up to m=7. Within the series, superior resolution of the ethoxymers with large values of m was achieved; however, the elution order was reversed for the m=1 and 0 ethoxymers, which produced overlapping of a few peaks within the series. A simple procedure for the accurate prediction of the concentrations of all the ethoxymers in industrial samples was described. After preconcentration with C18 solid-phase extraction cartridges, FAEs were also characterized and quantified in environmental samples (river and sea water). The LODs were ca. 2 microM (S/N=3) in the injected solutions.

  5. Cidades visíveis: fragmentos da vida urbana brasileira em cinema e TV contemporâneos

    Directory of Open Access Journals (Sweden)

    Angela Prysthon

    2008-09-01

    Full Text Available O propósito deste ensaio é pontuar a discussão sobre a existência das cidades midiáticas (especialmente aquelas do cinema e da televisão e sua relação com as cidades reais. Uma das hipóteses é que as cidades visíveis nos media não são necessariamente um reflexo do real, não correspondem a simulacros exatos do real, mas muitas vezes transformam o real, modificam o real. Visamos também investigar como se dá a relação entre a memória urbana midiática e a experiência concreta. Vamos comparar as cidades apresentadas em telenovelas e filmes de ficção com as cidades dos telejornais e documentários para, por meio de suas diferenças e, sobretudo, de suas semelhanças, entender como se processa a experiência urbana nos media. Palavras-chave: Cidades; representação; media; experiência; televisão; cinema. Abstract Our purpose with this essay is to discuss the existence of mediatic cities (particularly the cinema and television cities and their relation with real cities. One of the hypotheses is that the cities that are visible in the media do not necessarily reflect reality, they do not correspond to exact simulacraof the real, but in many occasions, they transform reality, they modify the real. We also seek to investigate the relations between the mediatic urban memory and the concrete experience, contrasting the cities presented by the news and documentaries with the cities formatted by soap operas and movies, and through their differences and similarities, understand how urban experience is processed by the media. Keywords: Cities; representation; media; experience; television; cinema.

  6. Uma visão da Europa em expressões plásticas ameríndias

    Directory of Open Access Journals (Sweden)

    Eduardo Peñuela Cañizal

    1994-08-01

    Full Text Available Os códices mesoamericanos têm o mérito adicional de nos fazer ver traços inesperados de imagens de Europa de maneira mais precisa quando ganham nova expressão em outras culturas. Com isso em mente, o objetivo de nossa apresentação é explorar determinadas formas que surgem quando o intérprete dos códices mesoamericanos pára para pensar sobre o tipo de relação que os diferentes sistemas semióticos - pictográfico, ideográfico e fonético - mantêm no espaço plástico do texto. Dessa perspectiva poderemos valorizar o significado poético das metáforas nas quais os ameríndios expressam visões peculiares das gentes e coisas européias.The Mesoamerican codices enable us to see, with a certain degree of precision, unexpected traits of images of Europe when shaped in other cultures. With this in mind, our paper aims to explore certain forms that show up when the interpreter of the afore mentioned codices focuses his interest in the type of relationship that the different semiotic systems - pictographic, ideographic and phonetic - maintain in the plastic space of the texts. From this perspective, it is possible to enjoy the poetic meaning of the metaphors used by the Amerindians in order to exprees unusual visions of European people and things.

  7. An Enhanced UV-Vis-NIR an d Flexible Photodetector Based on Electrospun ZnO Nanowire Array/PbS Quantum Dots Film Heterostructure.

    Science.gov (United States)

    Zheng, Zhi; Gan, Lin; Zhang, Jianbing; Zhuge, Fuwei; Zhai, Tianyou

    2017-03-01

    ZnO nanostructure-based photodetectors have a wide applications in many aspects, however, the response range of which are mainly restricted in the UV region dictated by its bandgap. Herein, UV-vis-NIR sensitive ZnO photodetectors consisting of ZnO nanowires (NW) array/PbS quantum dots (QDs) heterostructures are fabricated through modified electrospining method and an exchanging process. Besides wider response region compared to pure ZnO NWs based photodetectors, the heterostructures based photodetectors have faster response and recovery speed in UV range. Moreover, such photodetectors demonstrate good flexibility as well, which maintain almost constant performances under extreme (up to 180°) and repeat (up to 200 cycles) bending conditions in UV-vis-NIR range. Finally, this strategy is further verified on other kinds of 1D nanowires and 0D QDs, and similar enhancement on the performance of corresponding photodetecetors can be acquired, evidencing the universality of this strategy.

  8. Phase separation of in situ forming poly (lactide-co-glycolide acid) implants investigated using a hydrogel-based subcutaneous tissue surrogate and UV-vis imaging

    DEFF Research Database (Denmark)

    Sun, Yu; Jensen, Henrik; Petersen, Nickolaj J

    2017-01-01

    Phase separation of in situ forming poly (lactide-co-glycolide acid) (PLGA) implants with agarose hydrogels as the provider of nonsolvent (water) mimicking subcutaneous tissue was investigated using a novel UV-vis imaging-based analytical platform. In situ forming implants of PLGA-1-methyl-2......, water, to the in situ forming PLGA implants simulating the injection site environment. The resulting implant morphology depended on the stiffness of hydrogel matrix, indicating that the matrix in which implants are formed is of importance. Overall, the work showed that the UV-vis imaging-based platform...... with an agarose hydrogel mimicking the subcutaneous tissue holds potential in providing bio-relevant and mechanistic information on the phase separation processes of in situ forming implants....

  9. Aqueous-Phase Synthesis of Silver Nanodiscs and Nanorods in Methyl Cellulose Matrix: Photophysical Study and Simulation of UV–Vis Extinction Spectra Using DDA Method

    Directory of Open Access Journals (Sweden)

    Sarkar Priyanka

    2010-01-01

    Full Text Available Abstract We present a very simple and effective way for the synthesis of tunable coloured silver sols having different morphologies. The procedure is based on the seed-mediated growth approach where methyl cellulose (MC has been used as soft-template in the growth solution. Nanostructures of varying morphologies as well as colour of the silver sols are controlled by altering the concentration of citrate in the growth solution. Similar to the polymers in the solution, citrate ions also dynamically adsorbed on the growing silver nanoparticles and promote one (1-D and two-dimensional (2-D growth of nanoparticles. Silver nanostructures are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of the UV–vis extinction spectra of our synthesized silver nanostructures has been carried out using discrete dipole approximation (DDA method.

  10. Theoretical interpretation of the UV-vis spectrum of the CS2/Cl complex in the spectral region 320-550 nm.

    Science.gov (United States)

    Camacho, Cristopher; Cheng, Chi-Wen; Witek, Henryk A; Lee, Yuan-Pern

    2010-10-21

    Accurate multireference configuration interaction and time-dependent density functional calculations have been performed to interpret the experimental UV-vis spectrum of the CS(2)/Cl complex in the spectral region 320-550 nm. The molecular structure of the complex responsible for the previously observed UV-vis spectrum is recognized as ClSCS, not ClCS(2). Two low-lying excited states of ClSCS, responsible for its optical absorption, have been identified and analyzed. Optical excitation of ClSCS leads to the excitation-specific bond elongation that may lead to photofragmentation of the molecule. In addition, experimental conditions for verifying the presence of ClCS(2) are identified and detailed characterization of its optically active excited states with possible photofragmentation pathways is given.

  11. dd excitations in CPO-27-Ni metal-organic framework: comparison between resonant inelastic X-ray scattering and UV-vis spectroscopy.

    Science.gov (United States)

    Gallo, Erik; Lamberti, Carlo; Glatzel, Pieter

    2013-05-20

    We identify the dd excitations in the metal-organic framework CPO-27-Ni by coupling resonant inelastic X-ray scattering (RIXS) and UV-vis spectroscopy, and we show that the element selectivity of RIXS is crucial to observing the full dd multiplet structure, which is not visible in UV-vis. The combination of calculations using crystal-field multiplet theory and density functional theory can reproduce the RIXS spectral features, crucially improving interpretation of the experimental data. We obtain the crystal-field splitting and magnitude of the electron-electron interactions and correct previously reported values. RIXS instruments at synchrotron radiation sources are accessible to all researchers, and the technique can be applied to a broad range of systems.

  12. A new on-axis micro-spectrophotometer for combining Raman, fluorescence and UV/Vis absorption spectroscopy with macromolecular crystallography at the Swiss Light Source.

    Science.gov (United States)

    Pompidor, Guillaume; Dworkowski, Florian S N; Thominet, Vincent; Schulze-Briese, Clemens; Fuchs, Martin R

    2013-09-01

    The combination of X-ray diffraction experiments with optical methods such as Raman, UV/Vis absorption and fluorescence spectroscopy greatly enhances and complements the specificity of the obtained information. The upgraded version of the in situ on-axis micro-spectrophotometer, MS2, at the macromolecular crystallography beamline X10SA of the Swiss Light Source is presented. The instrument newly supports Raman and resonance Raman spectroscopy, in addition to the previously available UV/Vis absorption and fluorescence modes. With the recent upgrades of the spectral bandwidth, instrument stability, detection efficiency and control software, the application range of the instrument and its ease of operation were greatly improved. Its on-axis geometry with collinear X-ray and optical axes to ensure optimal control of the overlap of sample volumes probed by each technique is still unique amongst comparable facilities worldwide and the instrument has now been in general user operation for over two years.

  13. Two snakes from eastern Australia (Serpentes: Elapidae); a revised concept of Antaioserpens warro (De Vis) and a redescription of A. albiceps (Boulenger).

    Science.gov (United States)

    Couper, Patrick J; Peck, Stephen R; Emery, Jon-Paul; Keogh, J Scott

    2016-03-31

    Antaioserpens warro sensu lato is known from two populations, one in north-eastern Queensland (Qld), the other from south central Qld. Morphological and genetic assessments demonstrate that these widely separated populations represent two species. A re-examination of museum specimens and the type descriptions show that the name A. warro (De Vis) has been erroneously applied to the north-eastern Qld species. The type specimen of A. warro, from the Gladstone district in south-east Qld, is badly faded but the colour pattern as described by De Vis (1884a) is consistent with that of recently collected specimens from south central Qld and it is this species to which the name applies. The earliest available name for the species from north-eastern Qld is A. albiceps (Boulenger, 1898). Both A. warro and A. albiceps are redescribed herein.

  14. Multiconfigurational and DFT analyses of the electromeric formulation and UV-vis absorption spectra of the superoxide adduct of ferrous superoxide reductase.

    Science.gov (United States)

    Attia, Amr A A; Cioloboc, Daniela; Lupan, Alexandru; Silaghi-Dumitrescu, Radu

    2016-12-01

    The putative initial adduct of ferrous superoxide reductase (SOR) with superoxide has been alternatively formulated as ferric-peroxo or ferrous-superoxo. The ~600-nm UV-vis absorption band proposed to be assigned to this adduct (either as sole intermediate in the SOR catalytic cycle, or as one of the two intermediates) has recently been interpreted as due to a ligand-to-metal charge transfer, involving thiolate and superoxide in a ferrous complex, contrary to an alternative assignment as a predominantly cysteine thiolate-to-ferric charge transfer in a ferric-peroxo electromer. In an attempt to clarify the electromeric formulation of this adduct, we report a computational study using a multiconfigurational complete active space self-consistent field (MC-CASSCF) wave function approach as well as modelling the UV-vis absorption spectra with time-dependent density functional theory (TD-DFT). The MC-CASSCF calculations disclose a weak interaction between iron and the dioxygenic ligand and a dominant configuration with an essentially ferrous-superoxo character. The computed UV-vis absorption spectra reveal a marked dependence on the choice of density functional - both in terms of location of bands and in terms of orbital contributors. For the main band in the visible region, besides the recently reported thiolate-to-superoxide charge transfer, a more salient, and less functional-dependent, feature is a thiolate-to-ferric iron charge transfer, consistent with a ferric-peroxo electromer. By contrast, the computed UV-vis spectra of a ferric-hydroperoxo SOR model match distinctly better (and with no qualitative dependence on the DFT methodology) the 600-nm band as due to a mainly thiolate-to-ferric character - supporting the assignment of the SOR "600-nm intermediate" as a S=5/2 ferric-hydroperoxo species. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Hydration effects on the molecular structure of silica-supported vanadium oxide catalysts: A combined IR, Raman, UV–vis and EXAFS study

    OpenAIRE

    Keller, D.E.; Visser, T; Soulimani, F.; Koningsberger, D. C.; Weckhuysen, B.M.

    2007-01-01

    The effect of hydration on the molecular structure of silica-supported vanadium oxide catalysts with loadings of 1–16 wt.% V has been systematically investigated by infrared, Raman, UV–vis and EXAFS spectroscopy. IR and Raman spectra recorded during hydration revealed the formation of V–OH groups, characterized by a band at 3660 cm−1. Hydroxylation was found to start instantaneously upon exposure to traces of water, reflecting a very high sensitivity of the supported vanadium oxide catalysts ...

  16. UV/VIS SPECTROMETER DETERMINATION OF CAFFEINE IN GREEN COFFEE BEANS FROM HARARGHE, ETHIOPIA, USING BEER-LAMBERT’S LAW AND INTEGRATED ABSORPTION COEFFICIENT TECHNIQUES

    OpenAIRE

    EPHREM G. DEMISSIE; GIRMA W. WOYESSA; ARAYASELASSIE ABEBE

    2016-01-01

    A total of fifteen samples of green coffee (Coffea arabica L.) beans from the major producing region of Hararghe Ethiopia were studied using UV-Vis spectrometer measurement caffeine quantitative analysis from coffee beans. The number density of caffeine in green coffee beans has been reported using Beer-Lambert’s law and integrating absorption coefficient technique. Our results obtained using integrated absorption and Beer-Lambert’s law has a good agreement and we observed a maximum differenc...

  17. An operando optical fiber UV–vis spectroscopic study of the catalytic decomposition of NO and N2O over Cu-ZSM-5

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Groothaert, M.H.; Lievens, K.; Leeman, H.; Schoonheydt, R.A.

    2003-01-01

    The role of the bis(μ-oxo)dicopper core, i.e., [Cu2(μ-O)2]2+, in the decomposition of NO and N2O by the Cu-ZSM-5 zeolite has been studied with combined operando UV–vis monitoring of the catalyst and on-line GC analysis. An optical fiber was mounted on the outer surface of the quartz wall of the

  18. Use of UV-vis-NIR spectroscopy to monitor label-free interaction between molecular recognition elements and erythropoietin on a gold-coated polycarbonate platform.

    Science.gov (United States)

    Citartan, Marimuthu; Gopinath, Subash C B; Tominaga, Junji; Chen, Yeng; Tang, Thean-Hock

    2014-08-01

    Label-free-based detection is pivotal for real-time monitoring of biomolecular interactions and to eliminate the need for labeling with tags that can occupy important binding sites of biomolecules. One simplest form of label-free-based detection is ultraviolet-visible-near-infrared (UV-vis-NIR) spectroscopy, which measure changes in reflectivity as a means to monitor immobilization and interaction of biomolecules with their corresponding partners. In biosensor development, the platform used for the biomolecular interaction should be suitable for different molecular recognition elements. In this study, gold (Au)-coated polycarbonate was used as a platform and as a proof-of-concept, erythropoietin (EPO), a doping substance widely abused by the athletes was used as the target. The interaction of EPO with its corresponding molecular recognition elements (anti-EPO monoclonal antibody and anti-EPO DNA aptamer) is monitored by UV-vis-NIR spectroscopy. Prior to this, to show that UV-vis-NIR spectroscopy is a suitable method for measuring biomolecular interaction, the interaction between biotin and streptavidin was demonstrated via this strategy and reflectivity of this interaction decreased by 25%. Subsequent to this, interaction of the EPO with anti-EPO monoclonal antibody and anti-EPO DNA aptamer resulted in the decrease of reflectivity by 5% and 10%, respectively. The results indicated that Au-coated polycarbonate could be an ideal biosensor platform for monitoring biomolecular interactions using UV-vis-NIR spectroscopy. A smaller version of the Au-coated polycarbonate substrates can be derived from the recent set-up, to be applied towards detecting EPO abuse among atheletes. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Antimicrobial Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (VIS + wIRA Alters In Situ Oral Biofilms.

    Directory of Open Access Journals (Sweden)

    A Al-Ahmad

    Full Text Available Recently, growing attention has been paid to antimicrobial photodynamic therapy (aPDT in dentistry. Changing the microbial composition of initial and mature oral biofilm by aPDT using visible light plus water-filtered infrared-A wavelengths (VIS + wIRA has not yet been investigated. Moreover, most aPDT studies have been conducted on planktonic bacterial cultures. Therefore, in the present clinical study we cultivated initial and mature oral biofilms in six healthy volunteers for 2 hours or 3 days, respectively. The biofilms were treated with aPDT using VIS+wIRA (200 mW cm(-2, toluidine blue (TB and chlorine e6 (Ce6 for 5 minutes. Chlorhexidine treated biofilm samples served as positive controls, while untreated biofilms served as negative controls. After aPDT treatment the colony forming units (CFU of the biofilm samples were quantified, and the surviving bacteria were isolated in pure cultures and identified using MALDI-TOF, biochemical tests and 16S rDNA-sequencing. aPDT killed more than 99.9% of the initial viable bacterial count and 95% of the mature oral biofilm in situ, independent of the photosensitizer. The number of surviving bacterial species was highly reduced to 6 (TB and 4 (Ce6 in the treated initial oral biofilm compared to the 20 different species of the untreated biofilm. The proportions of surviving bacterial species were also changed after TB- and Ce6-mediated aPDT of the mature oral biofilm, resulting in a shift in the microbial composition of the treated biofilm compared to that of the control biofilm. In conclusion, aPDT using VIS + wIRA showed a remarkable potential to eradicate both initial and mature oral biofilms, and also to markedly alter the remaining biofilm. This encourages the clinical use of aPDT with VIS + wIRA for the treatment of periimplantitis and periodontitis.

  20. UV–vis spectroscopy study of plasma-activated water: Dependence of the chemical composition on plasma exposure time and treatment distance

    Science.gov (United States)

    Oh, Jun-Seok; Szili, Endre J.; Ogawa, Kotaro; Short, Robert D.; Ito, Masafumi; Furuta, Hiroshi; Hatta, Akimitsu

    2018-01-01

    Plasma-activated water (PAW) is receiving much attention in biomedical applications because of its reported potent bactericidal properties. Reactive oxygen and nitrogen species (RONS) that are generated in water upon plasma exposure are thought to be the key components in PAW that destroy bacterial and cancer cells. In addition to developing applications for PAW, it is also necessary to better understand the RONS chemistry in PAW in order to tailor PAW to achieve a specific biological response. With this in mind, we previously developed a UV–vis spectroscopy method using an automated curve fitting routine to quantify the changes in H2O2, NO2 ‑, NO3 ‑ (the major long-lived RONS in PAW), and O2 concentrations. A major advantage of UV–vis is that it can take multiple measurements during plasma activation. We used the UV–vis procedure to accurately quantify the changes in the concentrations of these RONS and O2 in PAW. However, we have not yet provided an in-depth commentary of how we perform the curve fitting procedure or its implications. Therefore, in this study, we provide greater detail of how we use the curve fitting routine to derive the RONS and O2 concentrations in PAW. PAW was generated by treatment with a helium plasma jet. In addition, we employ UV–vis to study how the plasma jet exposure time and treatment distance affect the RONS chemistry and amount of O2 dissolved in PAW. We show that the plasma jet exposure time principally affects the total RONS concentration, but not the relative ratios of RONS, whereas the treatment distance affects both the total RONS concentration and the relative RONS concentrations.

  1. Antimicrobial Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (VIS + wIRA) Alters In Situ Oral Biofilms

    Science.gov (United States)

    Al-Ahmad, A.; Bucher, M.; Anderson, A. C.; Tennert, C.; Hellwig, E.; Wittmer, A.; Vach, K.; Karygianni, L.

    2015-01-01

    Recently, growing attention has been paid to antimicrobial photodynamic therapy (aPDT) in dentistry. Changing the microbial composition of initial and mature oral biofilm by aPDT using visible light plus water-filtered infrared-A wavelengths (VIS + wIRA) has not yet been investigated. Moreover, most aPDT studies have been conducted on planktonic bacterial cultures. Therefore, in the present clinical study we cultivated initial and mature oral biofilms in six healthy volunteers for 2 hours or 3 days, respectively. The biofilms were treated with aPDT using VIS+wIRA (200 mW cm-2), toluidine blue (TB) and chlorine e6 (Ce6) for 5 minutes. Chlorhexidine treated biofilm samples served as positive controls, while untreated biofilms served as negative controls. After aPDT treatment the colony forming units (CFU) of the biofilm samples were quantified, and the surviving bacteria were isolated in pure cultures and identified using MALDI-TOF, biochemical tests and 16S rDNA-sequencing. aPDT killed more than 99.9% of the initial viable bacterial count and 95% of the mature oral biofilm in situ, independent of the photosensitizer. The number of surviving bacterial species was highly reduced to 6 (TB) and 4 (Ce6) in the treated initial oral biofilm compared to the 20 different species of the untreated biofilm. The proportions of surviving bacterial species were also changed after TB- and Ce6-mediated aPDT of the mature oral biofilm, resulting in a shift in the microbial composition of the treated biofilm compared to that of the control biofilm. In conclusion, aPDT using VIS + wIRA showed a remarkable potential to eradicate both initial and mature oral biofilms, and also to markedly alter the remaining biofilm. This encourages the clinical use of aPDT with VIS + wIRA for the treatment of periimplantitis and periodontitis. PMID:26162100

  2. ANALITICAL METHOD VALIDATION OF ANIONIC SURFACTANT SODIUM DODECYL BENZENE SULFONATE (SDBS) IN CATFISH BY UV-VIS SPECTROPHOTOMETRY USING ACRIDINE ORANGE

    OpenAIRE

    Monica Cahyaning Ratri; Adhitasari Suratman; Roto Roto

    2017-01-01

    The analytical method development on an anionic surfactant of sodium dodecylbenzenesulfonate (SDBS) in a catfish using spectrophotometer UV-Vis using acridine orange (AO) has been conducted. This research aims to determine the optimum conditions of analysis and to determine validation parameters of sodium dodecylbenzenesulfonate (SDBS) analysis in a catfish. This study was divided into two steps, isolation of sodium dodecyl benzene sulfonate (SDBS) in the catfish with soxhlet extraction and t...

  3. ESTUDIO POR ESPECTROFOTOMETRIA UV-VIS DE LA REACCIÓN ENTRE LOS IONES CIANURO Y EL PICRATO. UN EJEMPLO PRÁCTICO DE APLICACIONES ANALITICAS Y ESTUDIOS CINÉTICOS

    Directory of Open Access Journals (Sweden)

    Alberto de J Oliveros-Bastidas

    2009-06-01

    Full Text Available  La cinética de la reacción entre el ión cianuro y el picrato de sodio se estudió por espectrofotometría UV-Vis. Se observó una reacción de orden uno para ambos reactivos, así como un desplazamiento batocrómico de la señal de máxima absorbancia, incrementando la concentración de cualquiera de los reactivos, asociada a la formación de complejos de diferente estequiometría y resultando en los consiguientes cambios en los parámetros espectrométricos. Estos resultados sustentan una interacción de tipo p para el complejo resultante, resultado que se pudo generalizar utilizando otras moléculas donadoras que muestran las posibles interferencias de algunos compuestos químicos en las determinaciones cualitativas y cuantitativas de la frecuencia cianogénica y la determinación cuantitativa de glucósidos cianogénicos en plantas.

  4. In situ UV–vis investigation of growth of gold nanoparticles prepared by solution plasma sputtering in NaCl solution

    Energy Technology Data Exchange (ETDEWEB)

    Mizutani, Tsuyoshi, E-mail: mizutani.tsuyoshi@g.mbox.nagoya-u.ac.jp [Division of Quantum Science and Energy Engineering, Department of Materials, Physics and Energy Engineering, School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Ogawa, Satoshi [Division of Quantum Science and Energy Engineering, Department of Materials, Physics and Energy Engineering, School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Murai, Takaaki; Nameki, Hirofumi [Aichi Center for Industry and Science Technology, Onda, Kariya, Aichi 448-0013 (Japan); Yoshida, Tomoko; Yagi, Shinya [EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2015-11-01

    Highlights: • In situ UV–vis measurement reveals diameters of gold nanoparticles and concentrations of gold. • Ostwald ripening of gold nanoparticles occurs in NaCl solution. • We estimate equilibrium diameters of gold nanoparticles in various concentrations of NaCl solution. - Abstract: Gold nanoparticles are prepared in various concentrations of NaCl solutions by solution plasma sputtering. The absorption spectra of these solutions during and after the plasma process are measured by in situ ultraviolet–visible (UV–vis) spectroscopy to estimate the particle diameters and concentrations of gold. The distributions of particle diameters are obtained by transmission electron microscope (TEM) observations. These experiments indicate the gold nanoparticles with about 2.2 nm are directly formed by plasma phase and the diameters are increasing over time. These increases of particle diameters are caused by Ostwald ripening of gold nanoparticles in NaCl solution. We estimate the equilibrium diameter at which the gold nanoparticles are not solved in NaCl solution using in situ UV–vis spectroscopy. These diameters are about 5, 7 and 10 nm in 3, 5 and 10 mM NaCl solution, respectively. We make it possible to control the diameter of gold nanoparticles prepared by solution plasma sputtering in NaCl solution.

  5. Molecular dynamics simulation and TDDFT study of the structures and UV-vis absorption spectra of MCT-β-CD and its inclusion complexes.

    Science.gov (United States)

    Lu, Huijuan; Wang, Yujiao; Xie, Xiaomei; Chen, Feifei; Li, Wei

    2015-01-01

    In this research, the inclusion ratios and inclusion constants of MCT-β-CD/PERM and MCT-β-CD/CYPERM inclusion complexes were measured by UV-vis and fluorescence spectroscopy. The inclusion ratios are both 1:1, and the inclusion constants are 60 and 342.5 for MCT-β-CD/PERM and MCT-β-CD/CYPERM, respectively. The stabilities of inclusion complexes were investigated by MD simulation. MD shows that VDW energy plays a vital role in the stability of inclusion complex, and the destruction of inclusion complex is due to the increasing temperature. The UV-vis absorption spectra of MCT-β-CD and its inclusion complexes were studied by time-dependent density functional theory (TDDFT) method employing BLYP-D3, B3LYP-D3 and M06-2X-D3 functionals. BLYP-D3 well reproduces the UV-vis absorption spectrum and reveals that the absorption bands of MCT-β-CD mainly arise from n→π(∗) and n→σ(∗) transition, and those of inclusion complexes mainly arise from intramolecular charge transfer (ICT). ICT results in the shift of main absorption bands of MCT-β-CD. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. The color of complexes and UV-vis spectroscopy as an analytical tool of Alfred Werner's group at the University of Zurich.

    Science.gov (United States)

    Fox, Thomas; Berke, Heinz

    2014-01-01

    Two PhD theses (Alexander Gordienko, 1912; Johannes Angerstein, 1914) and a dissertation in partial fulfillment of a PhD thesis (H. S. French, Zurich, 1914) are reviewed that deal with hitherto unpublished UV-vis spectroscopy work of coordination compounds in the group of Alfred Werner. The method of measurement of UV-vis spectra at Alfred Werner's time is described in detail. Examples of spectra of complexes are given, which were partly interpreted in terms of structure (cis ↔ trans configuration, counting number of bands for structural relationships, and shift of general spectral features by consecutive replacement of ligands). A more complete interpretation of spectra was hampered at Alfred Werner's time by the lack of a light absorption theory and a correct theory of electron excitation, and the lack of a ligand field theory for coordination compounds. The experimentally difficult data acquisitions and the difficult spectral interpretations might have been reasons why this method did not experience a breakthrough in Alfred Werner's group to play a more prominent role as an important analytical method. Nevertheless the application of UV-vis spectroscopy on coordination compounds was unique and novel, and witnesses Alfred Werner's great aptitude and keenness to always try and go beyond conventional practice.

  7. Detection of olive oil adulteration by low-field NMR relaxometry and UV-Vis spectroscopy upon mixing olive oil with various edible oils

    Directory of Open Access Journals (Sweden)

    S. Ok

    2017-03-01

    Full Text Available Adulteration of olive oil using unhealthy substitutes is considered a threat for public health. Low-field (LF proton (1H nuclear magnetic resonance (NMR relaxometry and ultra-violet (UV visible spectroscopy are used to detect adulteration of olive oil. Three different olive oil with different oleoyl acyl contents were mixed with almond, castor, corn, and sesame oils with three volumetric ratios, respectively. In addition, Arbequina olive oil was mixed with canola, flax, grape seed, peanut, soybean, and sunflower seed oils with three volumetric ratios. Transverse magnetization relaxation time (T2 curves were fitted with bi-exponential decaying functions. T2 times of each mixture of olive oils and castor oils, and olive oils and corn oils changed systematically as a function of volumetric ratio. To detect the adulteration in the mixtures with almond and sesame oils, both LF 1H NMR relaxometry and UV-Vis spectroscopy were needed, where UV-Vis-spectroscopy detected the adulteration qualitatively. In the mixtures of Arbequina olive oil and flax, peanut, soybean, and sunflower seed oils, both T21 and T22 values became longer systematically as the content of the olive oil was decreased. The unique UV-Vis maximum absorbance of flax oil at 320.0 nm shows the adulteration of olive oil qualitatively.

  8. ANALISA FLAVONOID DARI EKSTRAK ETANOL 96% KULIT BUAH OKRA MERAH (Abelmoschus esculentus L. Moench SECARA KROMATOGRAFI LAPIS TIPIS DAN SPEKTROFOTOMETRI UV-VIS

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    Nia Lisnawati

    2016-03-01

    Full Text Available Has done research on flavonoids Analysis of Ethanol Extract 96% Fruit Leather Red Okra In Thin Layer Chromatography and Spectrophotometer UV-Vis. The purpose of this study was to analyze the content of the fruit skin red okra (Abelmoschus esculentus L. Moench by using the method of thin layer chromatography (TLC under UV light and spectrophotometry UV-Vis. Reference standards used in this study is the Standard Solution Routine Quercetin. The results of the research that has been done by the method of thin layer chromatography obtained Rf values of 0.81 and produces the color orange. And the results of research conducted by spectrophotometry UV-Vis method obtained 333,117 mg.L-1 or 421,629 mg.kg-1 or 0,84339 %. The conclusion from this study is that the 96% ethanol extract of the fruit leather red okra (Abelmoschus esculentus L. Moench positive (+ contains flavonoids with levels of 0,84339 %.

  9. Using UV-vis absorbance spectral parameters to characterize the fouling propensity of humic substances during ultrafiltration.

    Science.gov (United States)

    Zhou, Minghao; Meng, Fangang

    2015-12-15

    Ultrafiltration (UF) can achieve excellent removal of natural organic matter (NOM), but the main challenge for this process is the limited understanding of membrane fouling. The objective of this study is to explore the potential of UV-vis spectroscopic analysis for the detection of membrane fouling caused by humic acids (HA) at different solution chemistries (i.e., calcium ions (Ca(2+)) and pH). In the presence of Ca(2+), several spectral parameters, including the DSlope(325-375) (the slope of the log-transformed absorbance spectra over 325-375 nm), S(275-295) (the slope of the absorption coefficient over 257-295 nm) and S(R) (the ratio of S(275-295) to S(350-400)) of various HA solutions, were correlated with the molecule aggregation and the membrane fouling potential. Interestingly, increased DSlope(325-375) and decreased S(275-295) and S(R) were observed for the HA-Ca(2+) interaction under alkaline conditions (i.e., pH = 9) relative to those in lower pH environments (i.e., pH = 7 or 6), suggesting that spectral parameters were able to predict HA-Ca(2+) interactions under varying pH conditions. The strong correlations between the spectral parameters and the unified membrane fouling index (UMFI) obtained from UF experiments further corroborated that the spectral parameters were able to predict the membrane fouling potential. Moreover, the spectral parameters were also found to well reveal the fouling extent of the mixture of HA and Suwannee River NOM (SRNOM) or the pure SRNOM added with varying calcium concentrations, implying that the spectroscopic analysis was also available for the indication of practical NOM fouling. In addition, the measurement of S(275-295) and S(R) of the permeate solution suggests an increasing proportion of small-molecule HA in the permeate during the UF process. This study not only expands our knowledge of NOM-Ca(2+) aggregates as well as their role in membrane fouling behavior but also provides an approach for the in situ

  10. Trajetória de carreira: a pessoa e a carreira em uma visão contextualista.

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    Marcos Aurélio de Araujo Ferreira

    2013-06-01

    Full Text Available Observa-se a recorrente discussão sobre carreira na perspectiva do indivíduo ouda organização à luz do plano de carreira institucional. Contudo, particularmente nastrês últimas décadas, as recorrentes e cada vez mais freqüentes mudanças têm criadoreais rupturas sócio-políticas, econômicas e, talvez mais intensa, tecnológica. Adicionesea este fato as fusões, aquisições e outros tipos de combinações de empresase temos empiricamente evidências suficientes para revisitar o olhar da carreiraconsiderando a pessoa e a organização, sujeitos a um contexto em transformação.Cabe, portanto, analisar o que representa e como é representado o contexto, uma vezque os profissionais tanto são sujeitos como estão sujeitos ao contexto, assim comoas empresas na condição de organizações sociais, compostas por aqueles mesmoprofissionais, dentre outros interlocutores. Assim sendo, a proposta desta pesquisafoi de analisar em profundidade a interrelação da visão de carreira de uma executivaorganizacional que acelera sua trajetória de carreira como consequência de mudançassignificativas no modelo de negócios na organização em que atua. De analista semmuitas perspectivas passa a ocupar em prazos muito curtos posições superiores –coordenadora, gerente de projeto e gerente executiva, indicada como potencial para afunção de superintendência. Surpreende-se com o fato de que o tempo de ocupaçãode uma posição operacional é o tempo equivalente em que ascendeu à posição táticoestratégica.Percebe-se pela narrativa e o “enredo” de Isabel (pseudônimo que talaceleração pode ser viabilizada pela história construída também fora da organização,que lhe permitiu dar conta de novos níveis de complexidade em tempo reduzido,principalmente quando comparado com seus colegas – pares, equipe e superiores.

  11. Monitoring changes in the structure and properties of humic substances following ozonation using UV-Vis, FTIR and (1)H NMR techniques.

    Science.gov (United States)

    Rodríguez, Francisco J; Schlenger, Patrick; García-Valverde, María

    2016-01-15

    The main objective of this work is to conduct a comprehensive structural characterization of humic substances using the following experimental techniques: FTIR, 1H NMR and several UV–Vis parameters (Specific UV Absorbance at 254 nm or SUVA254, SUVA280, A400, the absorbance ratios A210/254, A250/365, A254/203, A254/436, A265/465, A270/400, A280/350, A465/665, the Absorbance Slope Index (ASI), the spectral slopes S275–295, S350–400 and the slope ratio SR). These UV–Vis parameters have also been correlated with key properties of humic substances such as aromaticity, molecular weight (MW) and trihalomethane formation potential (THMFP). An additional objective of this work is also to evaluate the usefulness of these techniques to monitor structural changes in humic substances produced by the ozonation treatment. Four humic substances were studied in this work: three of them were provided by the International Humic Substances Society (Suwannee River Fulvic Acid Standard: SRFA, Suwannee River Humic Acid Standard: SRHA and Nordic Reservoir Fulvic Acid Reference: NLFA) and the other one was a terrestrial humic acid widely used as a surrogate for aquatic humic substances in various studies (Aldrich Humic Acid: AHA). The UV–Vis parameters showing the best correlations with aromaticity in this study were SUVA254, SUVA280, A280/A350 ratio and A250/A364 ratio. The best correlations with molecular weight were for SUVA254, SUVA280 and A280/A350 ratio. Finally, in the case of the THMFP it was STHMFP-per mol HS the parameter showing good correlations with most of the UV–Vis parameters studied (especially with A280/A350 ratio, A265/A465 ratio and A270/A400 ratio) whereas STHMFP-per mg C showed poor correlations in most cases. On the whole, the UV–Vis parameter showing the best results was A280/A350 ratio as it showed excellent correlations for the three properties studied (aromaticity, MW and THMFP). A decrease in aromaticity following ozonation of humic substances can

  12. Visão retrospectiva em fibras alimentares com ênfase em beta-glucanas no tratamento do diabetes

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    Giane Sprada Mira

    2009-03-01

    Full Text Available Fibra alimentar refere-se aos componentes de plantas ou carboidratos análogos que são resistentes à digestão e absorção no intestino delgado humano. A American Dietetic Association recomenda ingestão de 20-35g de fibras ao dia. Evidências sugerem que uma dieta rica em fibras traz benefícios à manutenção da saúde, redução de risco e tratamento de doenças crônicas como a obesidade, doenças cardiovasculares, diverticulite e diabetes. As fibras são classificadas de acordo com a sua solubilidade em solúveis e insolúveis, com efeitos fisiológicos distintos. As insolúveis são responsáveis pelo aumento do bolo fecal e diminuição do tempo de trânsito intestinal. As solúveis retardam o esvaziamento gástrico e a absorção de glicose diminuindo a glicemia pós-prandial e reduzem o colesterol sérico devido à sua característica física de conferir viscosidade ao conteúdo luminal. As beta-glucanas são fibras altamente viscosas e seu consumo está relacionado à atenuação da resposta glicêmica e insulínica pós-prandial. A beta-glucana tem efeito sobre a degradação do amido e sobre o carboidrato disponível e conseqüentemente, sobre o índice glicêmico dos alimentos ingeridos. Recomenda-se sua ingestão com o objetivo de modular a glicemia e a necessidade de insulina, no tratamento da obesidade, doenças cardiovasculares e do diabetes. Este trabalho visa fornecer uma visão geral sobre beta-glucanas no tratamento do diabetes.Dietary fibers are defined as the component of the plants or analog carbohydrates that are resistant to digestion and absorption in the human small bowel. The America Dietetic Association recommends an ingestion of 20-30g of fiber per day. Evidences suggest that a diet rich in fibers brings benefits to health maintenance, by reducing the risk and the time of treatment of chronic diseases such as obesity, cardiovascular diseases, diverticulitis and diabetes. Fibers are classified as a soluble and

  13. Estudo eletrorretinográfico de visão cromática Electroretinographic study of chromatic vision

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    Daniela Cavalcanti Ferrara de Almeida Cunha

    2006-12-01

    Full Text Available OBJETIVO: O objetivo deste estudo é descrever o traçado eletrorretinográfico no gambá sul-americano (Didelphis aurita obtido com estímulo cromático de comprimento de onda seletivo. O eletrorretinograma é o registro das variações de voltagem nas células retinianas, desencadeadas por estímulo luminoso. O eletrorretinograma representa a atividade elétrica combinada de diferentes células, e sofre variações dependendo da fisiologia retiniana e do método de exame. MÉTODOS: Foram registrados os eletrorretinogramas de seis animais em adaptação ao escuro utilizando filtros cromáticos Kodak Wratten®, e registrada a sensibilidade espectral para comprimentos de onda específicos nas faixas de cores do azul, verde, amarelo, laranja e vermelho. RESULTADOS: Os resultados eletrorretinográficos mais consistentes foram obtidos quando o animal foi estimulado por faixas espectrais seletivas, ao invés de luz branca; e são consistentes com a curva de absorbância das opsinas descritas em fotorreceptores de marsupiais. Estudos prévios sugeriram a tricromacia dos marsupiais por microespectrofotometria de opsinas e imuno-histoquímica de retina. Esse fundamento morfológico não tinha demonstração fisiológica eletrorretinográfica, até este estudo. CONCLUSÃO: O gambá sul-americano tem se mostrado interessante como animal experimental no estudo comparativo da fisiologia visual em mamíferos, especialmente no estudo filogenético da visão cromática. Os marsupiais apresentam um modelo retiniano que superpõe os sistemas fotópico e escotópico; e o gênero Didelphis conserva características encontradas em fósseis do período pleoceno. Portanto, o sistema visual de um marsupial resgata características dos primórdios da evolução dos mamíferos, até o desenvolvimento dos padrões retinianos modernos.PURPOSE: To describe the electroretinogram of the South-American opossum (Didelphis aurita obtained by chromatic stimulus of specific

  14. Soil Organic Matter to Soil Organic Carbon ratios in recovered mountain peatlands using Vis-Nir spectroscopy approach.

    Science.gov (United States)

    Fernandez, Susana del Carmen; Valderrabano, Jesus; Peon, Juan Jose; Bueno, Alvaro

    2015-04-01

    The present research is part of a Life Project title "Inland Wetlands North of the Iberian Peninsula: Management and restoration of wetlands and hygrophilous environments" TREMEDAL (LIFE 11/ENV/ES/707) in which 25 wetland sites distributed by Galicia, Asturias, Castilla and León, País Vasco and Navarra were selected to be protected, restore or improve their conservation status and store seeds of bog plant species in the gene bank of Atlantic Botanic Garden of Gijon City, Spain. In Cantabrian Mountain Range two Poldjes (Glacio-Karstic depressions) site in Picos de Europa National Park were selected to develop an experimental action in the framework of the Life project. The selected sites harboring the most biodiverse peatland plant communities in the Cantabrian Mountain Range thus are in danger of extinction due to overgrazing. The action proposes the exclusion of livestock and wild herbivores in 5 parcels in order to contrast the differences in evolution of plant communities, hydrology and soil organic matter between grazed and non-grazed areas; and to determine future management measures that can reconcile traditional livestock raising with a better conservation of peatlands. The peatland are Vega of Liordes (Castilla-Leon) at an average altitude of 1868 m and filled mainly by clayed ferruginous sediments and Vega of Comella (Principality of Asturias) at an average altitude of 850 m and filled by at least 49 m of glacial and lacustrine sediments and 8 m of necromass from peatland vegetation. The soils developed are histosols under seasonal hydric regime in which the phreatic level suffers fluctuations over 30 cm along the year. At the time 0 (time fences were) 45 samples of the upper 15 cm of the histosols inside and outside the fences were taken. At the time 1 ( one year later) were re-sampled. Total organic carbon (TOC), Oxidizable Organic Carbon (OC), Carbonates presence and pH were analysis by chemical procedures. Also the Vis-Nir spectral analysis of the

  15. OMI/Aura Level 1B VIS Global Geolocated Earth Shine Radiances 1-orbit L2 Swath 13x24 km V003 (OML1BRVG) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Aura Ozone Monitoring Instrument (OMI) Level-1B (L1B) Geo-located Earth View VIS Radiance, Global-Mode (OML1BRVG) Version-3 product is now available to public...

  16. Charge-Transfer Complexes and Photochemistry of Ozone with Ferrocene and n-Butylferrocene: A UV-vis Matrix-Isolation Study.

    Science.gov (United States)

    Pinelo, Laura F; Kugel, Roger W; Ault, Bruce S

    2015-10-15

    The reactions of ozone with ferrocene (cp2Fe) and with n-butylferrocene (n-butyl cp2Fe) were studied using matrix isolation, UV-vis spectroscopy, and theoretical calculations. The codeposition of cp2Fe with O3 and of n-butyl cp2Fe with O3 into an argon matrix led to the production of 1:1 charge-transfer complexes with absorptions at 765 and 815 nm, respectively. These absorptions contribute to the green matrix color observed upon initial deposition. The charge-transfer complexes underwent photochemical reactions upon irradiation with red light (λ ≥ 600 nm). Theoretical UV-vis spectra of the charge-transfer complexes and photochemical products were calculated using TD-DFT at the B3LYP/6-311G++(d,2p) level of theory. The calculated UV-vis spectra were in good agreement with the experimental results. MO analysis of these long-wavelength transitions showed them to be n→ π* on the ozone subunit in the complex and indicated that the formation of the charge-transfer complex between ozone and cp2Fe or n-butyl cp2Fe affects how readily the π* orbital on O3 is populated when red light (λ ≥ 600 nm) is absorbed. 1:1 complexes of cp2Fe and n-butyl cp2Fe with O2 were also observed experimentally and calculated theoretically. These results support and enhance previous infrared studies of the mechanism of photooxidation of ferrocene by ozone, a reaction that has considerable significance for the formation of iron oxide thin films for a range of applications.

  17. UV-Vis/FT-NIR in situ monitoring of visible-light induced polymerization of PEGDA hydrogels initiated by eosin/triethanolamine/O2.

    Science.gov (United States)

    Kaastrup, Kaja; Aguirre-Soto, Alan; Wang, Chen; Bowman, Christopher N; Stansbury, Jeffery; Sikes, Hadley D

    In conjunction with a tertiary amine coinitiator, eosin, a photoreducible dye, has been shown to successfully circumvent oxygen inhibition in radical photopolymerization reactions. However, the role of O2 in the initiation and polymerization processes remains inconclusive. Here, we employ a UV-Vis/FT-NIR analytical tool for real-time, simultaneous monitoring of chromophore and monomer reactive group concentrations to investigate the eosin-activated photopolymerization of PEGDA-based hydrogels under ambient conditions. First, we address the challenges associated with spectroscopic monitoring of the polymerization of hydrogels using UV-Vis and FT-NIR, proposing metrics for quantifying the extent of signal loss from reflection and scattering, and showing their relation to microgelation and network formation. Second, having established a method for extracting kinetic information by eliminating the effects of changing refractive index and scattering, the coupled UV-Vis/FT-NIR system is applied to the study of eosin-activated photopolymerization of PEGDA in the presence of O2. Analysis of the inhibition time, rate of polymerization, and rate of eosin consumption under ambient and purged conditions indicates that regeneration of eosin in the presence of oxygen and consumption of oxygen occur via a nonchain process. This suggests that the uniquely high O2 resilience is due to alternative processes such as energy transfer from photo-activated eosin to oxygen. Uncovering the intricacies of the role of O2 in eosin-mediated initiation aids the design of O2 resistant free radical polymerization systems relevant to photonics, optoelectronics, biomaterials, and biosensing.

  18. Combination of UV-vis spectroscopy and chemometrics to understand protein-nanomaterial conjugate: a case study on human serum albumin and gold nanoparticles.

    Science.gov (United States)

    Wang, Yong; Ni, Yongnian

    2014-02-01

    Study of the interactions between proteins and nanomaterials is of great importance for understanding of protein nanoconjugate. In this work, we choose human serum albumin (HSA) and citrate-capped gold nanoparticles (AuNPs) as a model of protein and nanomaterial, and combine UV-vis spectroscopy with multivariate curve resolution by an alternating least squares (MCR-ALS) algorithm to present a new and efficient method for comparatively comprehensive study of evolution of protein nanoconjugate. UV-vis spectroscopy coupled with MCR-ALS allows qualitative and quantitative extraction of the distribution diagrams, spectra and kinetic profiles of absorbing pure species (AuNPs and AuNPs-HSA conjugate are herein identified) and undetectable species (HSA) from spectral data. The response profiles recovered are converted into the desired thermodynamic, kinetic and structural parameters describing the protein nanoconjugate evolution. Analysis of these parameters for the system gives evidence that HSA molecules are very likely to be attached to AuNPs surface predominantly as a flat monolayer to form a stable AuNPs-HSA conjugate with a core-shell structure, and the binding process takes place mainly through electrostatic and hydrogen-bond interactions between the positively amino acid residues of HSA and the negatively carboxyl group of citrate on AuNPs surface. The results obtained are verified by transmission electron microscopy, zeta potential, circular dichroism spectroscopy and Fourier transform infrared spectroscopy, showing the potential of UV-vis spectroscopy for study of evolution of protein nanoconjugate. In parallel, concentration evolutions of pure species resolved by MCR-ALS are used to construct a sensitive spectroscopic biosensor for HSA with a linear range from 1.8 nM to 28.1 nM and a detection limit of 0.8 nM. © 2013 Published by Elsevier B.V.

  19. UV-vis spectroscopy and colorimetric models for detecting anthocyanin-metal complexes in plants: An overview of in vitro and in vivo techniques.

    Science.gov (United States)

    Fedenko, Volodymyr S; Shemet, Sergiy A; Landi, Marco

    2017-05-01

    Although anthocyanin (ACN) biosynthesis is one of the best studied pathways of secondary metabolism in plants, the possible physiological and ecological role(s) of these pigments continue to intrigue scientists. Like other dihydroxy B-ring substituted flavonoids, ACNs have an ability to bind metal and metalloid ions, a property that has been exploited for a variety of purposes. For example, the metal binding ability may be used to stabilize ACNs from plant food sources, or to modify their colors for using them as food colorants. The complexation of metals with cyanidin derivatives can also be used as a simple, sensitive, cheap, and rapid method for determination concentrations of several metals in biological and environmental samples using UV-vis spectroscopy. Far less information is available on the ecological significance of ACN-metal complexes in plant-environment interactions. Metalloanthocyanins (protocyanin, nemophilin, commelinin, protodelphin, cyanosalvianin) are involved in the copigmentation phenomenon that leads to blue-pigmented petals, which may facilitate specific plant-pollinator interactions. ACN-metal formation and compartmentation into the vacuole has also been proposed to be part of an orchestrated detoxification mechanism in plants which experience metal/metalloid excess. However, investigations into ACN-metal interactions in plant biology may be limited because of the complexity of the analytical techniques required. To address this concern, here we describe simple methods for the detection of ACN-metal both in vitro and in vivo using UV-vis spectroscopy and colorimetric models. In particular, the use of UV-vis spectra, difference absorption spectra, and colorimetry techniques will be described for in vitro determination of ACN-metal features, whereas reflectance spectroscopy and colorimetric parameters related to CIE L(*)a(*)b(*) and CIE XYZ systems will be detailed for in vivo analyses. In this way, we hope to make this high-informative tool

  20. Determination of Hexavalent Chromium (Cr(VI Concentrations via Ion Chromatography and UV-Vis Spectrophotometry in Samples Collected from Nacogdoches Wastewater Treatment Plant, East Texas (USA

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    Kefa K. Onchoke

    2016-01-01

    Full Text Available The concentration of hexavalent chromium (Cr(VI, a toxic environmental pollutant and carcinogen, was determined in samples collected from Nacogdoches Wastewater Treatment Plant (NWWTP using ion chromatography and UV-visible spectrophotometry (IC, UV-Vis. On reaction with 1,5-diphenylcarbazide (DPC Cr+6 forms a 1,5-diphenylcarbazide-Cr(VI complex, which is then analyzed at 530 nm and 540 nm, respectively. Via ion chromatography Cr(VI concentrations were in the range of 0.00190±0.0020 and 0.0010±0.0006 ppm at the influent and effluent, respectively. With the use of standard addition wastewater samples were spiked with a 0.5 ppm Cr(VI standard of various amounts and subsequently analyzed with UV-Vis spectrophotometry. The spiked concentrations gave Cr(VI concentrations in the range of 0.0090±0.0060 ppm and 0.0040±0.0061 ppm at the influent and influent wastewater, respectively. The determined Cr(VI concentrations through the ion chromatography and UV-Vis spectrophotometry are below the maximum USEPA contaminant concentration of 0.1 ppm. From the analysis, the NWWTP efficiently removes Cr(VI before discharge into the environment through La Nana Creek. The removal efficiency for Cr(VI was determined to be ≥92.8% along the wastewater treatment stages from the influent (aeration stage to the effluent stages prior to discharge into the La Nana Creek.

  1. Analysis of pure tar substances (polycyclic aromatic hydrocarbons) in the gas stream using ultraviolet visible (UV-Vis) spectroscopy and multivariate curve resolution (MCR).

    Science.gov (United States)

    Weide, Tobias; Guschin, Viktor; Becker, Wolfgang; Koelle, Sabine; Maier, Simon; Seidelt, Stephan

    2015-01-01

    The analysis of tar, mostly characterized as polycyclic aromatic hydrocarbons (PAHs), describes a topic that has been researched for years. An online analysis of tar in the gas stream in particular is needed to characterize the tar conversion or formation in the biomass gasification process. The online analysis in the gas is carried out with ultraviolet-visible (UV-Vis) spectroscopy (190-720 nm). This online analysis is performed with a measuring cell developed by the Fraunhofer Institute for Chemical Technology (ICT). To this day, online tar measurements using UV-Vis spectroscopy have not been carried out in detail. Therefore, PAHs are analyzed as follows. The measurements are split into different steps. The first step to prove the online method is to vaporize single tar substances. These experiments show that a qualitative analysis of PAHs in the gas stream with the used measurement setup is possible. Furthermore, it is shown that the method provides very exact results, so that a differentiation of various PAHs is possible. The next step is to vaporize a PAH mixture. This step consists of vaporizing five pure substances almost simultaneously. The interpretation of the resulting data is made using a chemometric interpretation method, the multivariate curve resolution (MCR). The verification of the calculated results is the main aim of this experiment. It has been shown that the tar mixture can be analyzed qualitatively and quantitatively (in arbitrary units) in detail using the MCR. Finally it is the main goal of this paper to show the first steps in the applicability of the UV-Vis spectroscopy and the measurement setup on online tar analysis in view of characterizing the biomass gasification process. Due to that, the gasification plant (at the laboratory scale), developed and constructed by the Fraunhofer ICT, has been used to vaporize these substances. Using this gasification plant for the experiments enables the usage of the measurement setup also for the

  2. Abordagens semiquantitativa e quantitativa na avaliação da textura do solo por espectroscopia de reflectância bidirecional no VIS-NIR-SWIR

    Directory of Open Access Journals (Sweden)

    Marston Héracles Domingues Franceschini

    2013-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o potencial da espectroscopia de reflectância no VIS-NIR-SWIR, para a caracterização granulométrica de amostras de solos de diferentes classes texturais, e obter modelos de predição dos teores de argila, silte e areia no solo. Utilizou-se um conjunto de amostras representativas de Latossolos e Argissolo de cinco locais do Estado do Mato Grosso do Sul. Os espectros do visível e do infravermelho próximo ao infravermelho de ondas curtas (de 350 a 2.500 nm das amostras foram obtidos e analisados. Empregaram-se a análise de componentes principais (ACP, agrupamento por "fuzzy c-means", regressão logística multinomial (RLM e regressão por mínimos quadrados parciais. Espectros característicos para as diferentes classes texturais e a segregação de amostras de classes texturais e de locais de coleta com características distintas, por meio da ACP, "fuzzy c-means" e RLM, mostram o potencial semiquantitativo dos dados de reflectância no VIS-NIR-SWIR. Obteve-se quantificação satisfatória quanto à argila (R²=0,92, RPD=3,59, ao silte (R²=0,80, RPD=2,15 e à areia (R²=0,87, RPD=2,62. As técnicas de espectroscopia de reflectância podem auxiliar na determinação da textura e da variabilidade espacial do solo com metodologias semiquantitativas ou quantitativas.

  3. UV-Vis/FT-NIR in situ monitoring of visible-light induced polymerization of PEGDA hydrogels initiated by eosin/triethanolamine/O2

    Science.gov (United States)

    Kaastrup, Kaja; Aguirre-Soto, Alan; Wang, Chen; Bowman, Christopher N.; Stansbury, Jeffery; Sikes, Hadley D.

    2016-01-01

    In conjunction with a tertiary amine coinitiator, eosin, a photoreducible dye, has been shown to successfully circumvent oxygen inhibition in radical photopolymerization reactions. However, the role of O2 in the initiation and polymerization processes remains inconclusive. Here, we employ a UV-Vis/FT-NIR analytical tool for real-time, simultaneous monitoring of chromophore and monomer reactive group concentrations to investigate the eosin-activated photopolymerization of PEGDA-based hydrogels under ambient conditions. First, we address the challenges associated with spectroscopic monitoring of the polymerization of hydrogels using UV-Vis and FT-NIR, proposing metrics for quantifying the extent of signal loss from reflection and scattering, and showing their relation to microgelation and network formation. Second, having established a method for extracting kinetic information by eliminating the effects of changing refractive index and scattering, the coupled UV-Vis/FT-NIR system is applied to the study of eosin-activated photopolymerization of PEGDA in the presence of O2. Analysis of the inhibition time, rate of polymerization, and rate of eosin consumption under ambient and purged conditions indicates that regeneration of eosin in the presence of oxygen and consumption of oxygen occur via a nonchain process. This suggests that the uniquely high O2 resilience is due to alternative processes such as energy transfer from photo-activated eosin to oxygen. Uncovering the intricacies of the role of O2 in eosin-mediated initiation aids the design of O2 resistant free radical polymerization systems relevant to photonics, optoelectronics, biomaterials, and biosensing. PMID:26755925

  4. Qualidade de vida relacionada com a visão em pacientes com degeneração macular relacionada à idade neovascular

    Directory of Open Access Journals (Sweden)

    Maria Picoto

    2015-08-01

    Full Text Available RESUMO Objetivo: Avaliar o impacto da degeneração macular relacionada à idade (DMRI na qualidade de vida relacionada com a visão (QVRV numa amostra de pacientes portugueses. Métodos: Estudo observacional em corte transversal, não comparativo no qual foram incluídos 68 pacientes seguidos no departamento de Retina Médica do Serviço de Oftalmologia do Centro Hospitalar de Lisboa Ocidental, entre janeiro e abril de 2011. A QVRV foi avaliada por meio do questionário National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25, traduzido para o português. Os scores obtidos foram analisados e correlacionados com os seguintes parâmetros idade, sexo, lateralidade da doença, tempo de follow-up, acuidade visual (AV e EFC iniciais e finais do melhor (MO e pior olho (PO. Resultados: A AV do PO apresentou valor preditivo nos scores global, atividade para longe, visão cromática, visão periférica, desempenho, função social e saúde mental (p<0,05. Num modelo de multivariáveis com inclusão de todos os parâmetros clínicos analisados, as variáveis estudadas explicaram 60% da variância do score global (SG com um valor preditivo de 0,08 (R2 0,57, p=0,088. Conclusões: A DMRI NV está associada a uma diminuição da QVRV. A AV do PO tem valor preditivo nos scores do NEI-VFQ-25.

  5. Entre orquídeas e girassóis :o laboratório de Enfermagem na visão de estudantes

    OpenAIRE

    Gomes, Cleide Oliveira

    2004-01-01

    Estudar o processo ensino/aprendizagem acerca dos procedimentos de Enfermagem desenvolvidos no laboratório, apreendendo as dimensões sapiens e demens desse processo, é o propósito principal deste estudo. Tem como objetivos identificar as principais contribuições do laboratório de Enfermagem no processo ensino/aprendizagem, a partir da visão de estudantes de graduação, os sentimentos que eles expressam, descrever as dificuldades identificadas por estes e analisar a importância do laboratório n...

  6. DFT/TDDFT investigation on the chemical reactivities, aromatic properties, and UV-Vis absorption spectra of 1-butoxy-4-methoxybenzenepillar[5]arene constitutional isomers.

    Science.gov (United States)

    Zhang, Jian; Ren, Shuqing

    2016-09-01

    We investigate the chemical reactivities, aromatic properties, and UV-Vis absorption spectra of four constitutional isomers of 1-butoxy-4-methoxybenzenepillar[5]arene with the DFT and TDDFT methods. These characteristics in the gas and solvent phases are discussed on the basis of electronic energy, the highest occupied molecular orbital energy, electrophilicity, global hardness, chemical potential, and nucleus-independent chemical shift. The out-of-plane component of the NICS values reveals that there is a great contrast between aromatic rings of the isomer and benzene. The most intense wavelengths of BMpillar[5]arenes are all made up of delocalized-delocalized π → π* transition.

  7. Effects of Subsetting by Parent Materials on Prediction of Soil Organic Matter Content in a Hilly Area Using Vis-NIR Spectroscopy.

    Directory of Open Access Journals (Sweden)

    Shengxiang Xu

    Full Text Available Assessment and monitoring of soil organic matter (SOM quality are important for understanding SOM dynamics and developing management practices that will enhance and maintain the productivity of agricultural soils. Visible and near-infrared (Vis-NIR diffuse reflectance spectroscopy (350-2500 nm has received increasing attention over the recent decades as a promising technique for SOM analysis. While heterogeneity of sample sets is one critical factor that complicates the prediction of soil properties from Vis-NIR spectra, a spectral library representing the local soil diversity needs to be constructed. The study area, covering a surface of 927 km2 and located in Yujiang County of Jiangsu Province, is characterized by a hilly area with different soil parent materials (e.g., red sandstone, shale, Quaternary red clay, and river alluvium. In total, 232 topsoil (0-20 cm samples were collected for SOM analysis and scanned with a Vis-NIR spectrometer in the laboratory. Reflectance data were related to surface SOM content by means of a partial least square regression (PLSR method and several data pre-processing techniques, such as first and second derivatives with a smoothing filter. The performance of the PLSR model was tested under different combinations of calibration/validation sets (global and local calibrations stratified according to parent materials. The results showed that the models based on the global calibrations can only make approximate predictions for SOM content (RMSE (root mean squared error = 4.23-4.69 g kg-1; R2 (coefficient of determination = 0.80-0.84; RPD (ratio of standard deviation to RMSE = 2.19-2.44; RPIQ (ratio of performance to inter-quartile distance = 2.88-3.08. Under the local calibrations, the individual PLSR models for each parent material improved SOM predictions (RMSE = 2.55-3.49 g kg-1; R2 = 0.87-0.93; RPD = 2.67-3.12; RPIQ = 3.15-4.02. Among the four different parent materials, the largest R2 and the smallest RMSE

  8. Visões cibertemporais: a inserção do cyberpunk nos estudos de comunicação e cibercultura

    Directory of Open Access Journals (Sweden)

    Amaral, Adriana

    2005-01-01

    Full Text Available O trabalho apresenta uma leitura arque-genealógica do cyberpunk a partir de duas vertentes: como subgênero literário da ficção-científica e como uma visão do mundo contemporâneo, através de seu impacto cultural que engloba, além da literatura, uma subcultura de ordem da rebeldia juvenil, ou seja, a ficção-científica cyberpunk como uma teoria pré-figurativa social e cultural.

  9. Performance of an in-plane detection cell with integrated waveguides for UV/Vis absorbance measurements on microfluidic separation devices

    DEFF Research Database (Denmark)

    Petersen, Nickolaj Jacob; Mogensen, Klaus Bo; Kutter, Jörg Peter

    2002-01-01

    A microfluidic device with integrated waveguides and a long path length detection cell for UV/Vis absorbance detection is presented. The 750 mum U-cell detection geometry was evaluated in terms of its optical performance as well as its influence on efficiency for electrophoretic separations...... in the microdevice. Stray light was found to have a strong effect on both, the sensitivity of the detection and the available linear range. The long path length U-cell showed a 9 times higher sensitivity when compared to a conventional capillary electrophoresis (CE) system with a 75 mum inner diameter (ID) capillary...

  10. Pobreza, natureza e desenvolvimento: visões da América Latina nas páginas do The New York Times (1952-1961)

    OpenAIRE

    Saraiva, João Gilberto Neves

    2016-01-01

    Resumo: Este artigo trata das visões da América Latina enquanto espaço subdesenvolvido, demarcado pela pobreza e domínio da natureza, publicadas em matérias do jornal The New York Times. Analisa como a região foi construída em artigos, reportagens e editoriais como um lugar a ser transformado pelo conhecimento científico, tecnologia e capital dos Estados Unidos. Depois do fim da Segunda Guerra Mundial, a publicação atravessou um período de profundas transformações no seu quadro de funcionário...

  11. UV-VIS absorption spectra of molten AgCl and AgBr and of their mixtures with group I and II halide salts

    Energy Technology Data Exchange (ETDEWEB)

    Greening, Giorgio G.W. [Technische Universitaet Darmstadt (Germany). Eduard-Zintl-Institut fuer Anorganische und Physikalische Chemie

    2015-07-01

    The UV-VIS absorption spectra of (Ag{sub 1-X}[Li-Cs, Ba]{sub X})Cl and of (Ag{sub 1-X}[Na, K, Cs]{sub X})Br at 823 K at the concentrations X=0.0, 0.1, 0.2 have been measured. The findings show that on adding the respective halides to molten silver chloride and silver bromide, shifts of the fundamental absorption edge to shorter wavelengths result. A correlation between the observed shifts and the expansion of the silver sub-lattice is found, which is valid for both silver halide systems studied in this work.

  12. A questão da deterioração da qualidade de vida no trabalho na visão dos "bem-sucedidos"

    OpenAIRE

    Sanchez da Costa, Maria Carolina

    2010-01-01

    A presente dissertação visa investigar, dentro de uma abordagem dialética, a visão do trabalhador-executivo, pertencente ao grupo dos "bem-sucedidos", a cerca da realidade de deterioração da qualidade de vida no trabalho. Definimos como "bem-sucedidos" aqueles cuja alta qualificação acadêmica e profissional lhes possibilitam maior poder de escolha dentro do mercado de trabalho e, teoricamente, acesso a empregos por eles considerados mais próximos do ideal. No âmbito dessa dissertação nossos "...

  13. A experimentação problematizadora na visão de Delizoicov: Aplicabilidade em modelos atômicos

    OpenAIRE

    Lins, Vinícius de Sousa

    2016-01-01

    Este trabalho tem como objetivo analisar a experimentação problematizadora no ensino de Modelos Atômicos com base na visão de Delizoicov, verificando suas contribuições metodológicas no aprendizado dos alunos do 1º ano do ensino médio. Realizamos a exposição de alguns pontos teóricos, que buscam oferecer aportes para o tema abordado, criando assim meios e significados para o caminho escolhido. Caracterizando o tema, apresentamos a compreensão de que o aluno pode utilizar de seus prévios conhe...

  14. Estudio poblacional del visón americano ("Mustela vison") en Cataluña: ecología y control de una especie invasora

    OpenAIRE

    Melero Cavero, Yolanda

    2007-01-01

    Desde la introducción del visón americano en Europa, esta especie se ha convertido en un problema ecológico que implica la necesidad de su control. Existen varios métodos de control; sin embargo, actualmente, la opción más práctica y factible de control es el trampeo, combinado con la monitorización de las poblaciones para conocer su estado y dinámica poblacional. De ahí, que el objetivo principal de este estudio es proporcionar estrategias eficaces para el control de la población en Cataluña...

  15. CURRÍCULO INTEGRADO EM UM PROGRAMA DE INCLUSÃO SOCIAL: a visão dos gestores

    Directory of Open Access Journals (Sweden)

    Ilma Vieira do Nascimento Vieira do Nascimento

    2017-05-01

    Full Text Available RESUMO  Neste artigo, discute-se sobre o currículo integrado do Projovem na visão dos gestores do programa desenvolvido na cidade de São Luís-MA. Reflete-se sobre diferentes concepções do currículo e especificamente sobre a proposta de currículo integrado para analisar a concepção de currículo integrado que embasa a proposta curricular do Projovem, cuja organização contempla três dimensões: escolarização, qualificação profissional e ação comunitária. A partir dessa revisão teórica da produção acadêmica que aborda o currículo integrado, discute-se as percepções dos gestores sobre o desenvolvimento desse currículo no Projovem. Para tanto, realizou-se estudo exploratório, pesquisa de campo com os gestores, por meio de entrevistas. A análise dos dados evidencia que a integração acontece na perspectiva das três dimensões curriculares do programa, porém não há percepção clara de currículo integrado percebido no discurso dos gestores das escolas. Por fim, ressalta-se a importância do currículo integrado para formação integral do aluno, sendo que os conteúdos trabalhados devem se constituir em elementos concretos na sua formação, de modo a lhe favorecer possibilidades de compreensão e intervenção na realidade. Palavras-chave: Currículo integrado. Projovem. Dimensões curriculares. CURRICULUM INTEGRATED IN A SOCIAL INCLUSION PROGRAMME: the vision of managers ABSTRACT This article discusses about the integrated curriculum Projovem in view of Program Managers developed in São Luis-MA. Reflected on different conceptions of the curriculum and specifically on the proposed integrated curriculum to analyze the design of integrated curriculum that supports the curriculum proposal Projovem, whose organization has three dimensions: education, professional training and community action. From this theoretical review of academic literature that addresses the integrated curriculum, discusses the perceptions of

  16. Potential of VIS-NIR-SWIR Spectroscopy from the Chinese Soil Spectral Library for Assessment of Nitrogen Fertilization Rates in the Paddy-Rice Region, China

    Directory of Open Access Journals (Sweden)

    Shuo Li

    2015-05-01

    Full Text Available To meet growing food demand with limited land and reduced environmental impact, soil testing and formulated fertilization methods have been widely adopted around the world. However, conventional technology for investigating nitrogen fertilization rates (NFR is time consuming and expensive. Here, we evaluated the use of visible near-infrared shortwave-infrared (VIS-NIR-SWIR: 400–2500 nm spectroscopy for the assessment of NFR to provide necessary information for fast, cost-effective and precise fertilization rating. Over 2000 samples were collected from paddy-rice fields in 10 Chinese provinces; samples were added to the Chinese Soil Spectral Library (CSSL. Two kinds of modeling strategies for NFR, quantitative estimation of soil N prior to classification and qualitative by classification, were employed using partial least squares regression (PLSR, locally weighted regression (LWR, and support vector machine discriminant analogy (SVMDA. Overall, both LWR and SVMDA had moderate accuracies with Cohen’s kappa coefficients of 0.47 and 0.48, respectively, while PLSR had fair accuracy (0.37. We conclude that VIS-NIR-SWIR spectroscopy coupled with the CSSL appears to be a viable, rapid means for the assessment of NFR in paddy-rice soil. Based on qualitative classification of soil spectral data only, it is recommended that the SVMDA be adopted for rapid implementation.

  17. Computing UV/vis spectra using a combined molecular dynamics and quantum chemistry approach: bis-triazin-pyridine (BTP) ligands studied in solution.

    Science.gov (United States)

    Höfener, Sebastian; Trumm, Michael; Koke, Carsten; Heuser, Johannes; Ekström, Ulf; Skerencak-Frech, Andrej; Schimmelpfennig, Bernd; Panak, Petra J

    2016-03-21

    We report a combined computational and experimental study to investigate the UV/vis spectra of 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridine (BTP) ligands in solution. In order to study molecules in solution using theoretical methods, force-field parameters for the ligand-water interaction are adjusted to ab initio quantum chemical calculations. Based on these parameters, molecular dynamics (MD) simulations are carried out from which snapshots are extracted as input to quantum chemical excitation-energy calculations to obtain UV/vis spectra of BTP ligands in solution using time-dependent density functional theory (TDDFT) employing the Tamm-Dancoff approximation (TDA). The range-separated CAM-B3LYP functional is used to avoid large errors for charge-transfer states occurring in the electronic spectra. In order to study environment effects with theoretical methods, the frozen-density embedding scheme is applied. This computational procedure allows to obtain electronic spectra calculated at the (range-separated) DFT level of theory in solution, revealing solvatochromic shifts upon solvation of up to about 0.6 eV. Comparison to experimental data shows a significantly improved agreement compared to vacuum calculations and enables the analysis of relevant excitations for the line shape in solution.

  18. Phase separation of in situ forming poly (lactide-co-glycolide acid) implants investigated using a hydrogel-based subcutaneous tissue surrogate and UV-vis imaging.

    Science.gov (United States)

    Sun, Yu; Jensen, Henrik; Petersen, Nickolaj J; Larsen, Susan W; Østergaard, Jesper

    2017-10-25

    Phase separation of in situ forming poly (lactide-co-glycolide acid) (PLGA) implants with agarose hydrogels as the provider of nonsolvent (water) mimicking subcutaneous tissue was investigated using a novel UV-vis imaging-based analytical platform. In situ forming implants of PLGA-1-methyl-2-pyrrolidinone and PLGA-triacetin representing fast and slow phase separating systems, respectively, were evaluated using this platform. Upon contact with the agarose hydrogel, the phase separation of the systems was followed by the study of changes in light transmission and absorbance as a function of time and position. For the PLGA-1-methyl-2-pyrrolidinone system, the rate of spatial phase separation was determined and found to decrease with increasing the PLGA concentration from 20% to 40% (w/w). Hydrogels with different agarose concentrations (1% and 10% (w/v)) were prepared for providing the nonsolvent, water, to the in situ forming PLGA implants simulating the injection site environment. The resulting implant morphology depended on the stiffness of hydrogel matrix, indicating that the matrix in which implants are formed is of importance. Overall, the work showed that the UV-vis imaging-based platform with an agarose hydrogel mimicking the subcutaneous tissue holds potential in providing bio-relevant and mechanistic information on the phase separation processes of in situ forming implants. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Quantification of Coffea arabica and Coffea canephora var. robusta concentration in blends by means of synchronous fluorescence and UV-Vis spectroscopies.

    Science.gov (United States)

    Dankowska, A; Domagała, A; Kowalewski, W

    2017-09-01

    The potential of fluorescence, UV-Vis spectroscopies as well as the low- and mid-level data fusion of both spectroscopies for the quantification of concentrations of roasted Coffea arabica and Coffea canephora var. robusta in coffee blends was investigated. Principal component analysis was used to reduce data multidimensionality. To calculate the level of undeclared addition, multiple linear regression (PCA-MLR) models were used with lowest root mean square error of calibration (RMSEC) of 3.6% and root mean square error of cross-validation (RMSECV) of 7.9%. LDA analysis was applied to fluorescence intensities and UV spectra of Coffea arabica, canephora samples, and their mixtures in order to examine classification ability. The best performance of PCA-LDA analysis was observed for data fusion of UV and fluorescence intensity measurements at wavelength interval of 60nm. LDA showed that data fusion can achieve over 96% of correct classifications (sensitivity) in the test set and 100% of correct classifications in the training set, with low-level data fusion. The corresponding results for individual spectroscopies ranged from 90% (UV-Vis spectroscopy) to 77% (synchronous fluorescence) in the test set, and from 93% to 97% in the training set. The results demonstrate that fluorescence, UV, and visible spectroscopies complement each other, giving a complementary effect for the quantification of roasted Coffea arabica and Coffea canephora var. robusta concentration in blends. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A novel method to quantify the adulteration of extra virgin olive oil with low-grade olive oils by UV-vis.

    Science.gov (United States)

    Torrecilla, José S; Rojo, Ester; Domínguez, Juan C; Rodríguez, Francisco

    2010-02-10

    A simple and novel method to quantify adulterations of extra virgin olive oil (EVOO) with refined olive oil (ROO) and refined olive-pomace oil (ROPO) is described here. This method consists of calculating chaotic parameters (Lyapunov exponent, autocorrelation coefficients, and two fractal dimensions, CPs) from UV-vis scans of adulterated EVOO samples. These parameters have been successfully linearly correlated with the ROO or ROPO concentrations in 396 EVOO adulterated samples. By an external validation process, when the adulterating agent concentration is less than 10%, the integrated CPs/UV-vis model estimates the adulterant agent concentration with a mean correlation coefficient (estimated versus real concentration of low grade olive oil) greater than 0.97 and a mean square error of less than 1%. In light of these results, this detector is suitable not only to detect adulterations but also to measure impurities when, for instance, a higher grade olive oil is transferred to another storage tank in which lower grade olive oil was stored that had not been adequately cleaned.

  1. UV-Vis spectrophotometry of quinone flow battery electrolyte for in situ monitoring and improved electrochemical modeling of potential and quinhydrone formation.

    Science.gov (United States)

    Tong, Liuchuan; Chen, Qing; Wong, Andrew A; Gómez-Bombarelli, Rafael; Aspuru-Guzik, Alán; Gordon, Roy G; Aziz, Michael J

    2017-12-06

    Quinone-based aqueous flow batteries provide a potential opportunity for large-scale, low-cost energy storage due to their composition from earth abundant elements, high aqueous solubility, reversible redox kinetics and their chemical tunability such as reduction potential. In an operating flow battery utilizing 9,10-anthraquinone-2,7-disulfonic acid, the aggregation of an oxidized quinone and a reduced hydroquinone to form a quinhydrone dimer causes significant variations from ideal solution behavior and of optical absorption from the Beer-Lambert law. We utilize in situ UV-Vis spectrophotometry to establish (a), quinone, hydroquinone and quinhydrone molar attenuation profiles and (b), an equilibrium constant for formation of the quinhydrone dimer (KQHQ) ∼ 80 M-1. We use the molar optical attenuation profiles to identify the total molecular concentration and state of charge at arbitrary mixtures of quinone and hydroquinone. We report density functional theory calculations to support the quinhydrone UV-Vis measurements and to provide insight into the dimerization conformations. We instrument a quinone-bromine flow battery with a Pd-H reference electrode in order to demonstrate how complexation in both the negative (quinone) and positive (bromine) electrolytes directly impacts measured half-cell and full-cell voltages. This work shows how accounting for electrolyte complexation improves the accuracy of electrochemical modeling of flow battery electrolytes.

  2. Design and experience with the WS/HS assembly movement using labview VIS, national instrument motion controllers, and compumotor electronic drive units and motors

    Energy Technology Data Exchange (ETDEWEB)

    Day, L. A. (Lisa A.); Gilpatrick, J. D. (John Douglas); Gruchalla, M. (Michael); Martinez, D. G. (Derwin G.); O' Hara, J. F. (James F.); Shurter, R. B. (Robert B.); Stettler, M. W. (Matthew W.); Valdiviez, R. (Robert); Barr, D. S. (Dean S.)

    2001-01-01

    The Low-Energy Demonstration Accelerator (LEDA), designed and built at the Los Alamos National Laboratory, is part of the Accelerator Production of Tritium (APT) program and provides a platform for measuring high-power proton beam-halo formation. The technique used for measuring the beam halo employs nine combination Wire Scanner and Halo Scraper (WS/HS) devices. This paper will focus on the experience gained in the use of National Instrument (NI) LabVIEW VIs and motion controllers, and Compumotor electronic drive units and motors. The base configuration couples a Compumotor motor driven by a Parker-Hannifin Gemini GT Drive unit. The drive unit is controlled by a NI PXI-7344 controller card, which in turn is controlled by a PC running custom built NI LabVIEW VIs. The function of the control VI's is to interpret instructions from the main control system, the Experimental Physics and Industrial Control System (EPICS), and carry out the corresponding motion commands. The main control VI has to run all nineteen WS/HS motor axes used in the accelerator. A basic discussion of the main accelerator control system, EPICs which is hosted on a VXI platform, and its interface with the PC based LabVIEW motion control software will be included.

  3. DESIGN AND EXPERIENCE WITH THE WS/HS ASSEMBLY MOVEMENT USING LABVIEW VIS, NATIONAL INSTRUMENT MOTION CONTROLLERS, AND COMPUMOTOR ELECTRONIC DRIVE UNITS AND MOTORS

    Energy Technology Data Exchange (ETDEWEB)

    D.S. BARR; L.A. DAY; ET AL

    2001-06-01

    The Low-Energy Demonstration Accelerator (LEDA), designed and built at the Los Alamos National Laboratory, is part of the Accelerator Production of Tritium (APT) program and provides a platform for measuring high-power proton beam-halo formation. The technique used for measuring the beam halo employs nine combination Wire Scanner and Halo Scraper (WS/HS) devices. This paper will focus on the experience gained in the use of National Instrument (NI) LabVIEW VIs and motion controllers, and Compumotor electronic drive units and motors. The base configuration couples a Compumotor motor driven by a Parker-Hannifin Gemini GT Drive unit. The drive unit is controlled by a NI PXI-7344 controller card, which in turn is controlled by a PC running custom built NI LabVIEW VIs. The function of the control VI's is to interpret instructions from the main control system, the Experimental Physics and Industrial Control System (EPICS), and carry out the corresponding motion commands. The main control VI has to run all nineteen WS/HS motor axes used in the accelerator. A basic discussion of the main accelerator control system, EPICs which is hosted on a VXI platform, and its interface with the PC based LabVIEW motion control software will be included.

  4. Assessment of repeatability of composition of perfumed waters by high-performance liquid chromatography combined with numerical data analysis based on cluster analysis (HPLC UV/VIS - CA).

    Science.gov (United States)

    Ruzik, L; Obarski, N; Papierz, A; Mojski, M

    2015-06-01

    High-performance liquid chromatography (HPLC) with UV/VIS spectrophotometric detection combined with the chemometric method of cluster analysis (CA) was used for the assessment of repeatability of composition of nine types of perfumed waters. In addition, the chromatographic method of separating components of the perfume waters under analysis was subjected to an optimization procedure. The chromatograms thus obtained were used as sources of data for the chemometric method of cluster analysis (CA). The result was a classification of a set comprising 39 perfumed water samples with a similar composition at a specified level of probability (level of agglomeration). A comparison of the classification with the manufacturer's declarations reveals a good degree of consistency and demonstrates similarity between samples in different classes. A combination of the chromatographic method with cluster analysis (HPLC UV/VIS - CA) makes it possible to quickly assess the repeatability of composition of perfumed waters at selected levels of probability. © 2014 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  5. [Study of pH measuring based on i-motif DNA conformation switch and UV-Vis absorption spectroscopy of gold nanoparticles].

    Science.gov (United States)

    Zhong, Jian-hai; Guo, Liang-qia; Wu, Jin-mei; Chen, Jin-feng; Chen, Zhang-jie

    2012-04-01

    A fast, sensitive, colorimetric method for the detection of pH based on the differentiate effect of gold nanoparticles to the configuration of DNA was developed in this study. The UV-Vis absorption spectroscopy of the i-motif DNA-Au NPs system has been investigated, and the effect of the concentration of salt and i-motif DNA, reaction time and DNA sequence on the pH response of the system have been also optimized. Under the optimum conditions, the UV-Vis absorption spectroscopy of the Au NPs is changed regularly with pH in the range of 5.3 - 7.0, the absorbance at 520 nm is increased gradually while at 700 nm decreased. Correspondingly, the color of the Au NPs is varied from violet to red. The pH sensor is no need to modification, low cost, fast and can be carried out by naked eyes. It is promising to use in monitoring some life process which associated with pH variation.

  6. The characterization of the concentration of the single-walled carbon nanotubes in aqueous dispersion by UV-Vis-NIR absorption spectroscopy.

    Science.gov (United States)

    Yang, Bing; Ren, Lingling; Li, Luming; Tao, Xingfu; Shi, Yunhua; Zheng, Yudong

    2013-11-07

    Current and future applications of single-wall carbon nanotubes (SWCNTs) depend on the dispersion of the SWCNTs in aqueous solution and their quantitation. The concentration of SWCNTs is an important indicator to evaluate the dispersibility of the surfactant-dispersed SWCNTs suspension. Due to the complexity of the SWCNTs suspension, it is necessary to determine both the total concentration of the dispersed SWCNTs and the concentration of individually dispersed SWCNTs in aqueous suspensions, and these were evaluated through the absorbance and the resonance ratios of UV-Vis-NIR absorption spectra, respectively. However, there is no specific and reliable position assigned for either calculation of the absorbance or the resonance ratio of the UV-Vis-NIR absorption spectrum. In this paper, different ranges of wavelengths for these two parameters were studied. From this, we concluded that the wavelength range between 300 nm and 600 nm should be the most suitable for evaluation of the total concentration of dispersed SWCNTs in the suspension; also, wavelengths below 800 nm should be most suitable for evaluation of the concentration of individually dispersed SWCNTs in the suspension. Moreover, these wavelength ranges are verified by accurate dilution experiments.

  7. Effect of the solvent on the size of clay nanoparticles in solution as determined using an ultraviolet-visible (UV-Vis) spectroscopy methodology.

    Science.gov (United States)

    Alin, Jonas; Rubino, Maria; Auras, Rafael

    2015-06-01

    Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ nanoscale measurement of the size of mineral clay agglomerates in various liquid suspensions. The clays studied were organomodified and unmodified montmorillonite clays (I.44p, Cloisite 93a, and PGN). The methodology was compared and validated against dynamic light scattering (DLS) analysis. The method was able to measure clay agglomerates in solvents in situations where DLS analysis was unsuccessful due to the shapes, polydispersity, and high aspect ratios of the clay particles and the complexity of the aggregates, or dispersion medium. The measured clay agglomerates in suspension were found to be in the nanometer range in the more compatible solvents, and their sizes correlated with the Hansen solubility parameter space distance between the clay modifiers and the solvents. Mass detection limits for size determination were in the range from 1 to 9 mg/L. The methodology thus provides simple, rapid, and inexpensive characterization of clays or particles in the nano- or microsize range in low concentrations in various liquid media, including complex mixtures or highly viscous fluids that are difficult to analyze with DLS. In addition, by combining UV-VIS spectroscopy with DLS it was possible to discern flocculation behavior in liquids, which otherwise could result in false size measurements by DLS alone.

  8. Novel methodology for the extraction and identification of natural dyestuffs in historical textiles by HPLC-UV-Vis-ESI MS. Case study: chasubles from the Wawel Cathedral collection.

    Science.gov (United States)

    Lech, Katarzyna; Jarosz, Maciej

    2011-03-01

    High-performance liquid chromatography coupled with spectrophotometric and electrospray mass spectrometric detection (HPLC-UV-Vis-ESI MS) was used for characterization of natural dyes present in historical art works. The gradient program was developed for identification of 29 colorants of various polarities. Dual detection system (UV-Vis and ESI MS) allowed differentiation of all compounds, even if they were not completely separated. This enabled examination of more color compounds over a substantially shorter time in comparison with previously recommended methods. Moreover, for extraction of colorants from historical textiles a two-step sequential procedure was proposed, excluding evaporation used in earlier procedures. The developed method was successfully applied to identification of indigotin, carminic, kermesic, flavokermesic, dcII, dcIV, dcVII, and ellagic acids as well as luteolin, apigenin, and genistein in red, violet, and green fibers taken from three selected historical chasubles which belong to the collection of the Wawel Cathedral treasury (Cracow, Poland). Italian textiles from the fifteenth and sixteenth centuries, of which chasubles were made, were dyed with a limited number of dyestuffs, consistently used for all batches of fabrics. The obtained results also allowed confirmation of the structure of the so-called "dcII" component of cochineal as a C-glucose derivative of flavokermesic acid.

  9. Characterization and dating of blue ballpoint pen inks using principal component analysis of UV-Vis absorption spectra, IR spectroscopy, and HPTLC.

    Science.gov (United States)

    Senior, Samir; Hamed, Ezzat; Masoud, Mamdouh; Shehata, Eman

    2012-07-01

    The ink of pens and ink extracted from lines on white photocopier paper of 10 blue ballpoint pens were subjected to ultraviolet-visible (UV-Vis) spectroscopy, infrared (IR), and high-performance thin-layer liquid chromatography (HPTLC). The R(f) values and color tones of the bands separated by thin-layer chromatography (TLC) analysis used to classify the writing inks into three groups. The principal component analysis (PCA) investigates the pen responsible for a piece of writing, and how time affects spectroscopy of written ink. PCA can differentiate between pen ink and ink line indicates the influence of solvent extraction process on the results. The PCA loadings are useful in individualization of a questioned ink from a database. The PCA of ink lines extracted at different times can be used to estimate the time at which a questioned document was written. The results proved that the UV-Vis spectra are effective tool to separate blue ballpoint pen ink in most cases rather than IR and HPTLC. © 2012 American Academy of Forensic Sciences.

  10. As dobras semióticas do ciberespaço: da web visível à invisível

    Directory of Open Access Journals (Sweden)

    Silvana Drumond Monteiro

    Full Text Available Após a instituição do ciberespaço, na década de 1990, a Web tornou-se o seu principal constructo e vem dobrando e desdobrando-se em vários sentidos: Web Invisível, Web Visível, Web Semântica, Web Pragmática, Web Social ou 2.0, entre outras. Em relação à Web Invisível, de acordo com os autores que escrevem sobre o tema, existe a inquietante questão: que nome dar a esse (desterritório? Web Invisível, Profunda, Oculta, Escura? A partir da compreensão do conceito de dobra, criado por Leibniz e ressignificado por Deleuze, que explica os agenciamentos maquínicos e a visão pragmática dos aspectos técnicos e materiais das semióticas, fez-se uma prospecção conceitual da Web Invisível e de alguns mecanismos de busca que fazem a dobra com essa Web no ciberespaço. Para além da literatura, descobriu-se uma Web verdadeiramente escura, a DarkWeb, paralela e underground utilizada para o bem e para o mal, como previsível da espécie humana.

  11. LC-MS profiling of glucosinolates in the seeds of Brassica elongata Ehrh., and of the two stenoendemic B. botteri Vis and B. cazzae Ginzb. & Teyber.

    Science.gov (United States)

    Montaut, Sabine; Blažević, Ivica; Ruščić, Mirko; Rollin, Patrick

    2017-01-01

    The glucosinolates (GLs) present in seed extracts of Brassica elongata Ehrh., B. botteri Vis and B. cazzae Ginzb. & Teyber from Croatia were identified by LC-MS. 4-Hydroxyindol-3-ylmethyl GL (3) was the major GL in the seeds of B. elongata, along with the four minor GLs 2-(R)-hydroxy-3-butenyl- (1), 3-butenyl- (2), 4-pentenyl- (4) and indol-3-ylmethyl (5). The seeds of B. botteri (Vis island) and B. cazzae (Sušac island) contained 2 as the major GL as well as 1, 3, 5 and 4-methoxyindol-3-ylmethyl GL (6). However, the GLs in B. botteri (Palagruža island) differed from other varieties having 2-propenyl GL (7) as the major GL in the seeds, and the four minor GLs 2, 3, 5 and 6. This first report of the GL content in the seeds of B. elongata, B. botteri and B. cazzae indicates that the unique GL profiles could be specific to the geographical origin of the plant.

  12. Time dependent profile retrieval of UV/vis absorbing radicals from balloon-borne limb measurements – a case study on NO2 and O3

    Directory of Open Access Journals (Sweden)

    R. Schofield

    2010-07-01

    Full Text Available A new "Bayesian" minimization algorithm for the retrieval of the diurnal variation of UV/vis absorbing radicals (O3, NO2, BrO, OClO and HONO from balloon-borne limb scattered skylight observations is discussed. The method evaluates spectroscopic measurements in combination with radiative transfer calculations to drive a mathematical inversion on a discrete time and height grid. Here, the proposed method is applied to data obtained during two deployments of the mini-DOAS instrument on different balloon payloads in northern Brazil in June 2005. The retrieval is tested by comparing the inferred profiles to in-situ ozone sounding data and to measurements of the ENVISAT/SCIAMACHY satellite instrument performed during a collocated overpass. The comparison demonstrates the strength and validity of our approach. In particular for time-varying radical concentrations, photochemical corrections due to temporal mismatch of the corresponding observations are rendered dispensable. Thus, limb scanning UV/vis spectrometry from balloon platforms offers a more direct and concise approach for satellite validation of radical measurements than solar occultation measurements. Furthermore, monitoring of the diurnal variation of stratospheric radicals allows us to constrain photochemical parameters which are critical for stratospheric ozone chemistry, such as the photolysis frequency of N2O5 by observations of the diurnal variation of NO2.

  13. Comparative evaluation of natural and acid-modified layered mineral materials as rimifon-carriers using UV/VIS, FTIR, and equilibrium sorption study

    Directory of Open Access Journals (Sweden)

    Nedyalka Georgieva

    2015-12-01

    Full Text Available The encapsulation of rimifon on natural (NZ and acid-modified (AMZ zeolites was investigated by UV/VIS, FTIR, and equilibrium sorption studies in aqueous medium. The UV/VIS and FTIR spectral investigations provided data on the nature and characteristics of the drug–zeolite complexes. The probable host–guest interactions during rimifon encapsulation in AMZ include van der Waals interactions, as well as H-bonds established between the O-atom from the carbonyl (>C=O group and N-pyridine/N-hydrazine atoms in rimifon and zeolite OH-groups. The maximum experimental equilibrium sorption capacity of AMZ (qmax = 7.17 mg/g was approximately 24 times higher than that of NZ. Baudu and Fritz–Schlunder isotherms almost overlapped and seemed to be the best-fitting models with regard to the experimental equilibrium data of rimifon sorption on AMZ. The unique properties of AMZ and the established high extend of rimifon encapsulation proved the possibility of its successful application as rimifon-carrier for environmental and medical purposes.

  14. Corneocyte quantification by NIR densitometry and UV/Vis spectroscopy for human and porcine skin and the role of skin cleaning procedures.

    Science.gov (United States)

    Schwarz, J C; Klang, V; Hoppel, M; Wolzt, M; Valenta, C

    2012-01-01

    Optical methods of corneocyte quantification during tape stripping experiments on the skin are useful tools for the rapid evaluation of the skin penetration potential of dermally applied substances. However, a comparative investigation of the different methods proposed for this task, namely NIR densitometry and UV/Vis spectroscopy, is still missing. Thus, the aim of the present work was to employ these two techniques in comparative tape stripping experiments both in vivo on human forearm skin and in vitro on porcine ear skin. Standard tape stripping experiments were performed in the absence and presence of a marketed formulation containing flufenamic acid as a model drug. In the context of these methodological investigations, different methods of skin cleaning prior to the tape stripping procedure were evaluated to identify the most appropriate working protocol among the approaches proposed in the respective literature. The results showed that the investigated methods of NIR densitometry and UV/Vis spectroscopy deliver highly comparable results. Both optical methods are suitable to determine the skin penetration profiles of active substances during in vivo and in vitro tape stripping, especially if a simple working protocol without any cleaning procedures is maintained. Copyright © 2012 S. Karger AG, Basel.

  15. Ambiente e saúde: visão de profissionais da saúde da família

    Directory of Open Access Journals (Sweden)

    Ana Flávia Quintão Fonseca

    2012-08-01

    Full Text Available A temática saúde e ambiente vem sendo amplamente discutida através de disciplinas tanto do campo da saúde quanto das ciências ambientais. No âmbito de uma visão ampliada de saúde, torna-se desejável que os profissionais desse campo de conhecimento apresentem um maior envolvimento na discussão acerca da temática saúde e ambiente. O objetivo deste trabalho é identificar e compreender as percepções, ideias e imagens de alguns profissionais da Saúde da Família sobre a articulação entre saúde e ambiente. A presente pesquisa foi realizada na perspectiva das Ciências Sociais sendo desenvolvida no contexto da abordagem qualitativa. Realizou-se a análise das informações obtidas de profissionais pertencentes a uma regional de Saúde de Belo Horizonte. Para a definição do número de participantes, foi utilizado o critério de saturação. Como técnica de análise das informações, utilizou-se a análise de conteúdo, desenvolvida na perspectiva da representação social. A coleta de informações foi realizada através de entrevistas semiestruturadas. A partir da análise das informações obtidas, foram apreendidas duas categorias de análise. Foi possível observar que, apesar da significativa percepção em relação à interação entre saúde e ambiente, essa percepção se mostra limitada e reducionista. A despeito de toda a complexidade do sistema de organização da Saúde da Família na atenção à saúde, a discussão sobre saúde e ambiente, como um saber necessário à prática ampliada da saúde, parece não se fazer presente de maneira abrangente e integrada com a discussão atual. Encontra-se, ainda, desvinculada de um enfoque ecossistêmico de saúde.La temática salud y ambiente ha sido ampliamente discutida en todas las disciplinas del campo de las ciencias de la salud y del medio ambiente. Dentro de una visión ampliada de la salud, es deseable que los profesionales en este campo del conocimiento tienen una

  16. Influência dos estímulos ambientais domiciliares na mobilidade de crianças com baixa visão: habilidade funcional e assistência do cuidador

    Directory of Open Access Journals (Sweden)

    Janaine Brandão Lage

    Full Text Available RESUMO Objetivo: Analisar e correlacionar a influência dos estímulos presentes no ambiente domiciliar nas habilidades funcionais e no nível de assistência do cuidador na mobilidade de crianças com baixa visão e visão normal. Métodos: Participaram sete crianças com diagnóstico de baixa visão (32,29 ± 7,09 meses e sete com visão normal (31,57 ± 6,90 meses. Os instrumentos utilizados foram Affordances in the Home Environment for Motor Development - Self Report (AHEMD-SR e Inventário de Avaliação Pediátrica de Incapacidade (PEDI referente à parte I (habilidades funcionais e II (assistência do cuidador da área de mobilidade. Resultados: De acordo com o PEDI, não houve diferença significativa entre crianças com baixa visão e visão normal nas habilidades funcionais (U=13,5; p=0,076 e na assistência do cuidador (U=13,0; p=0,083 na área de mobilidade, porém houve correlação moderada (r=+0,756; p=0,049 entre as partes I e II para crianças com baixa visão. No AHEMD-SR, crianças com baixa visão apresentaram diferenças significativas nas subescalas: motricidade fina (U=7,5; p=0,024, motricidade grossa (U=7,5; p=0,024 e AHEMD total (U=8,0; p=0,035. Porém ambas receberam a classificação "média" para as oportunidades de estimulação do ambiente domiciliar. Conclusão: O ambiente domiciliar das crianças com baixa visão apresentou razoáveis oportunidades de estímulos, no entanto seu desempenho estava dentro dos padrões de normalidade para as habilidades funcionais e assistência do cuidador em mobilidade.

  17. Revealing Lattice Expansion of Small-Pore Zeolite Catalysts during the Methanol-to-Olefins Process Using Combined Operando X-ray Diffraction and UV–vis Spectroscopy

    KAUST Repository

    Goetze, Joris

    2018-02-06

    In small-pore zeolite catalysts, where the size of the pores is limited by eight-ring windows, aromatic hydrocarbon pool molecules that are formed inside the zeolite during the Methanol-to-Olefins (MTO) process cannot exit the pores and are retained inside the catalyst. Hydrocarbon species whose size is comparable to the size of the zeolite cage can cause the zeolite lattice to expand during the MTO process. In this work, the formation of retained hydrocarbon pool species during MTO at a reaction temperature of 400 °C was followed using operando UV–vis spectroscopy. During the same experiment, using operando X-ray Diffraction (XRD), the expansion of the zeolite framework was assessed, and the activity of the catalyst was measured using online gas chromatography (GC). Three different small-pore zeolite frameworks, i.e., CHA, DDR, and LEV, were compared. It was shown using operando XRD that the formation of retained aromatic species causes the zeolite lattice of all three frameworks to expand. Because of the differences in the zeolite framework dimensions, the nature of the retained hydrocarbons as measured by operando UV–vis spectroscopy is different for each of the three zeolite frameworks. Consequently, the magnitude and direction of the zeolite lattice expansion as measured by operando XRD also depends on the specific combination of the hydrocarbon species and the zeolite framework. The catalyst with the CHA framework, i.e., H-SSZ-13, showed the biggest expansion: 0.9% in the direction along the c-axis of the zeolite lattice. For all three zeolite frameworks, based on the combination of operando XRD and operando UV–vis spectroscopy, the hydrocarbon species that are likely to cause the expansion of the zeolite cages are presented; methylated naphthalene and pyrene in CHA, 1-methylnaphthalene and phenalene in DDR, and methylated benzene and naphthalene in LEV. Filling of the zeolite cages and, as a consequence, the zeolite lattice expansion causes the

  18. Use of High-Frequency, In-Stream, Ultraviolet-Visual (UV-vis) Spectroscopy to Characterize Organic Carbon and Nitrogen Species in Watershed Runoff

    Science.gov (United States)

    Winters, C. G.; Rowland, R. D.; Inamdar, S. P.

    2014-12-01

    Natural or anthropogenic episodic events such as snowmelt, floods, fire, insect-defoliation, pollutant spills, etc. can result in sudden and unexpected changes in runoff water quality from watersheds. Depending on the magnitude and intensity of the change, such events which are also occasionally referred to as "hot moments", can have significant ecological and environmental consequences. Measuring and recording such rapid and unexpected changes in runoff quality has always been a logistical challenge. However, the advent of in-situ, UV- and fluorescence-based spectrometers that can continuously measure water quality changes at high-frequency (minutes to hours) show considerable promise. We implemented a UV-vis spectrometer (Spectrolyser, S::CAN Inc.) to characterize the stream water quality at every 30 minutes from a small (12 ha) forested watershed located in the Piedmont region of Maryland. The spectrometer recorded the UV-Vis spectrum (200-750 nm), turbidity (NTU), nitrate-N (mgN/L), and total and dissolved organic carbon (TOC and DOC, respectively; mgC/L). To evaluate the accuracy of the sensor values, water sampling was also performed simultaneously using automated ISCO samplers for multiple storms since November 2013. Water samples have been analyzed for suspended solids, particulate and dissolved forms of organic carbon (OC), and nitrate-N. In addition, water samples were also analyzed on laboratory spectrometers to develop a variety of UV and fluorescence metrics that characterize the lability and recalcitrance of DOC. Key questions that we address here are: How reliable and accurate are the spectrometer values for dissolved and particulate species of OC and nitrate-N? How does the magnitude of the storms and the amount of suspended sediment influence the accuracy of sensor readings? Can the sensor UV-vis data provide insights into DOC character/composition similar to those derived from lab-based UV and fluorescence metrics? Addressing these questions is

  19. Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (vis+wIRA and Chlorine e6 (Ce6 eradicates Planktonic Periodontal Pathogens and Subgingival Biofilms

    Directory of Open Access Journals (Sweden)

    Ali Al-Ahmad

    2016-11-01

    Full Text Available Alternative treatment methods for pathogens and microbial biofilms are required due to the widespread rise in antibiotic resistance. Antimicrobial photodynamic therapy (aPDT has recently gained attention as a novel method to eradicate pathogens. The aim of this study was to evaluate the antimicrobial effects of a novel aPDT method using visible light (vis and water infiltrated infrared A (wIRA in combination with chlorine e6 (Ce6 against different periodontal pathogens in planktonic form and within in situ subgingival oral biofilms. Eight different periodontal pathogens were exposed to aPDT using vis+wIRA and 100 µg/ml Ce6 in planktonic culture. Additionally, pooled subgingival dental biofilm was also treated by aPDT and the number of viable cells determined as colony forming units (CFU. Live/dead staining was used in combination with confocal laser scanning microscopy (CLSM to visualize and quantify antimicrobial effects within the biofilm samples. Untreated negative controls as well as 0.2 % chlorhexidine (CHX-treated positive controls were used. All eight tested periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Eikenella corrodens, Actinomyces odontolyticus, Fusobacterium nucleatum, Parvimonas micra, Slackia exigua and Atopopium rimae and the aPDT-treated subgingival biofilm were eliminated over the ranges of 3.43 - 8.34 and 3.91 - 4.28 log10 CFU in the log10 scale, respectively. Thus, aPDT showed bactericidal effects on the representative pathogens as well as on the in situ subgingival biofilm. The live/dead staining also revealed a significant reduction (33.45 % of active cells within the aPDT-treated subgingival biofilm. Taking the favorable tissue healing effects of vis+wIRA into consideration, the significant antimicrobial effects revealed in this study highlight the potential of aPDT using this light source in combination with Ce6 as an adjunctive method to treat periodontitis as well as

  20. Discrimination of various paper types using diffuse reflectance ultraviolet-visible near-infrared (UV-Vis-NIR) spectroscopy: forensic application to questioned documents.

    Science.gov (United States)

    Kumar, Raj; Kumar, Vinay; Sharma, Vishal

    2015-06-01

    Diffuse reflectance ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy is applied as a means of differentiating various types of writing, office, and photocopy papers (collected from stationery shops in India) on the basis of reflectance and absorbance spectra that otherwise seem to be almost alike in different illumination conditions. In order to minimize bias, spectra from both sides of paper were obtained. In addition, three spectra from three different locations (from one side) were recorded covering the upper, middle, and bottom portions of the paper sample, and the mean average reflectivity of both the sides was calculated. A significant difference was observed in mean average reflectivity of Side A and Side B of the paper using Student's pair >t-test. Three different approaches were used for discrimination: (1) qualitative features of the whole set of samples, (2) principal component analysis, and (3) a combination of both approaches. On the basis of the first approach, i.e., qualitative features, 96.49% discriminating power (DP) was observed, which shows highly significant results with the UV-Vis-NIR technique. In the second approach the discriminating power is further enhanced by incorporating the principal component analysis (PCA) statistical method, where this method describes each UV-Vis spectrum in a group through numerical loading values connected to the first few principal components. All components described 100% variance of the samples, but only the first three PCs are good enough to explain the variance (PC1 = 51.64%, PC2 = 47.52%, and PC3 = 0.54%) of the samples; i.e., the first three PCs described 99.70% of the data, whereas in the third approach, the four samples, C, G, K, and N, out of a total 19 samples, which were not differentiated using qualitative features (approach no. 1), were therefore subjected to PCA. The first two PCs described 99.37% of the spectral features. The discrimination was achieved by using a loading plot between