SORCE XPS Level 3 Solar Spectral Irradiance 6-Hour Means V010

Data.gov (United States)

National Aeronautics and Space Administration — The SORCE XUV Photometer System (XPS) Solar Spectral Irradiance (SSI) 6-Hour Data Product SOR3XPS6 contains solar XUV irradiances in the 0.1 to 27 nm range, as well...

XPS, AES and laser raman spectroscopy: A fingerprint for a materials surface characterisation

International Nuclear Information System (INIS)

Zaidi Embong

2011-01-01

This review briefly describes some of the techniques available for analysing surfaces and illustrates their usefulness with a few examples such as a metal and alloy. In particular, Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and laser Raman spectroscopy are all described as advanced surface analytical techniques. In analysing a surface, AES and XPS would normally be considered first, with AES being applied where high spatial resolution is required and XPS where chemical state information is needed. Laser Raman spectroscopy is useful for determining molecular bonding. A combination of XPS, AES and Laser Raman spectroscopy can give quantitative analysis from the top few atomic layers with a lateral spatial resolution of < 10 nm. (author)

PLA-PMMA blends: A study by XPS and ToF-SIMS

International Nuclear Information System (INIS)

Cossement, D.; Gouttebaron, R.; Cornet, V.; Viville, P.; Hecq, M.; Lazzaroni, R.

2006-01-01

This paper reports which are the possibilities of quantification by time of flight secondary ion mass spectrometry (ToF-SIMS) for some polymer blends. In order to assess the composition of the mixtures, we studied first different poly(L-lactide)/polymethylmethacrylate (PLA/PMMA) blends by X-ray photoelectron spectroscopy (XPS), this technique being quantitative. By XPS fitting of the C 1s level, we found a very good agreement of the measured concentrations with the initial compositions. Concerning ToF-SIMS data treatment, we used principal component analysis (PCA) on negative spectra allowing to discriminate one polymer from the other one. By partial least square regression (PLS), we found also a good agreement between the ToF-SIMS predicted and initial compositions. This shows that ToF-SIMS, in a similar way to XPS, can lead to quantitative results. In addition, the observed agreement between XPS (60-100 A depth analyzed) and ToF-SIMS (10 A depth analyzed) measurements show that there is no segregation of one of the two polymers onto the surface

Quantitative analysis of satellite structures in XPS spectra of gold and silver

Energy Technology Data Exchange (ETDEWEB)

Pauly, N., E-mail: nipauly@ulb.ac.be [Université libre de Bruxelles, Service de Métrologie Nucléaire (CP 165/84), 50 av. F. D. Roosevelt, B-1050 Brussels (Belgium); Yubero, F. [Instituto de Ciencia de Materiales de Sevilla, Univ. Sevilla – CSIC, av. Américo Vespucio 49, E-41092 Sevilla (Spain); Tougaard, S. [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M (Denmark)

2016-10-15

Highlights: • Accurate determination of the energy loss functions for Au and Ag. • Calculation of effective inelastic electron scattering cross sections for Au and Ag. • Convolution of these cross sections with varying model primary spectra F(E). • Variation of F(E) until a good agreement with experimental XPS spectra is reached. • Quantitative determination of Au 4f and Ag 3d characteristics. - Abstract: Identification of specific chemical states and local electronic environments at surfaces by X-ray photoelectron spectroscopy (XPS) is often difficult because it is not straightforward to quantitatively interpret the shape and intensity of shake-up structures that originate from the photoexcitation process. Indeed the shape and intensity of measured XPS structures are strongly affected by both extrinsic excitations due to electron transport out of the surface and intrinsic excitations induced by the sudden creation of the static core hole. These processes must be taken into account to quantitatively extract, from experimental XPS, the primary excitation spectrum of the considered transition which includes all effects that are part of the initial photo-excitation process, i.e. lifetime broadening, spin–orbit coupling, and multiplet splitting. It was previously shown [N. Pauly, S. Tougaard, F. Yubero, Surf. Sci. 620 (2014) 17] that both extrinsic and intrinsic excitations could be included in an effective energy-differential inelastic electron scattering cross section for XPS which is then convoluted with the primary excitation spectrum to model the full XPS spectrum. This method can thus be applied to determine the primary excitation spectrum from any XPS spectrum. We use this approach in the present paper to determine the Au 4f and Ag 3d photoemission spectra from pure metals. We observe that characteristic energy loss features of the XPS spectra are not only due to photoelectron energy losses. We thus prove the existence of a double shake-up process

Generalized molybdenum oxide surface chemical state XPS determination via informed amorphous sample model

Energy Technology Data Exchange (ETDEWEB)

Baltrusaitis, Jonas, E-mail: job314@lehigh.edu [Department of Chemical Engineering, Lehigh University, B336 Iacocca Hall, 111 Research Drive, Bethlehem, PA 18015 (United States); PhotoCatalytic Synthesis group, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Meander 229, P.O. Box 217, 7500 AE Enschede (Netherlands); Mendoza-Sanchez, Beatriz [CRANN, Chemistry School, Trinity College Dublin, Dublin (Ireland); Fernandez, Vincent [Institut des Matériaux Jean Rouxel, 2 rue de la Houssinière, BP 32229, F-44322 Nantes Cedex 3 (France); Veenstra, Rick [PhotoCatalytic Synthesis group, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Meander 229, P.O. Box 217, 7500 AE Enschede (Netherlands); Dukstiene, Nijole [Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Radvilenu pl. 19, LT-50254 Kaunas (Lithuania); Roberts, Adam [Kratos Analytical Ltd, Trafford Wharf Road, Wharfside, Manchester, M17 1GP (United Kingdom); Fairley, Neal [Casa Software Ltd, Bay House, 5 Grosvenor Terrace, Teignmouth, Devon TQ14 8NE (United Kingdom)

2015-01-30

Highlights: • We analyzed and modeled spectral envelopes of complex molybdenum oxides. • Molybdenum oxide films of varying valence and crystallinity were synthesized. • MoO{sub 3} and MoO{sub 2} line shapes from experimental data were created. • Informed amorphous sample model (IASM) developed. • Amorphous molybdenum oxide XPS envelopes were interpreted. - Abstract: Accurate elemental oxidation state determination for the outer surface of a complex material is of crucial importance in many science and engineering disciplines, including chemistry, fundamental and applied surface science, catalysis, semiconductors and many others. X-ray photoelectron spectroscopy (XPS) is the primary tool used for this purpose. The spectral data obtained, however, is often very complex and can be subject to incorrect interpretation. Unlike traditional XPS spectra fitting procedures using purely synthetic spectral components, here we develop and present an XPS data processing method based on vector analysis that allows creating XPS spectral components by incorporating key information, obtained experimentally. XPS spectral data, obtained from series of molybdenum oxide samples with varying oxidation states and degree of crystallinity, were processed using this method and the corresponding oxidation states present, as well as their relative distribution was elucidated. It was shown that monitoring the evolution of the chemistry and crystal structure of a molybdenum oxide sample due to an invasive X-ray probe could be used to infer solutions to complex spectral envelopes.

Research and industrial application of x-ray photoelectron spectroscopy (XPS) in Malaysia

International Nuclear Information System (INIS)

Mohd Ambar Yarmo; Abd Razak Daud; Abdul Kariem Arof

2000-01-01

As a developing country, Malaysia is fully committed to research and development especially for industrial development. One of priority fields is advanced materials and surface analysis of such materials is an important aspect in research. Among the tools for surface science analysis is x-ray photoelectron spectroscopy (XPS) which can be considered new to this country. The industrial sector is also keen to solve their problems and developing their products using XPS. The microelectronic and electrical industries are interested in solving problems related to metal-metal joining , gold silica peeling, surface corrosion and surface coating. The glove industry uses XPS to solve problems due to staining and color fading of their products. Research conducted in universities and research institutes that mainly deal with catalysis, membranes for fuel cells, sensors, batteries, corrosion phenomena and interface interaction in coating finds XPS a useful technique for surface studies. Specific examples from various sectors will be presented in this paper. (Author)

Thorough XPS analyses on overlithiated manganese spinel cycled around the 3V plateau

Energy Technology Data Exchange (ETDEWEB)

Grissa, R. [IPREM ECP − UMR CNRS 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau-Pyrénées, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France); Martinez, H., E-mail: herve.martinez@univ-pau.fr [IPREM ECP − UMR CNRS 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau-Pyrénées, 2 Avenue du Président Angot, 64053 Pau Cedex 9 (France); Cotte, S.; Galipaud, J.; Pecquenard, B. [CNRS, Université de Bordeaux, ICMCB–UPR 9048 and Bordeaux INP, 87 Avenue du Dr. Schweitzer, F-33600 Pessac (France); Cras, F.Le [CEA LETI, 17 rue des Martyrs, F-38054 Grenoble (France); Université Grenoble Alpes, F-38000 Grenoble (France)

2017-07-31

Highlights: • Mn2p XPS spectra of Li{sub 1+x}Mn{sub 2-x}O{sub 4} (0 < x < 0.25) fitted with reference samples. • XPS Mn mean oxidation states agrees with XRD structural study. • Li{sub 1.2}Mn{sub 1.8}O{sub 4} thin films cycled versus lithium arounds 3 V in liquid electrolyte. • Electrochemical results (over 20 cycles) related to Mn oxidation states evolution. • Irreversible capacity explained on the basis of XPS by active material delamination. - Abstract: Lithium-rich spinel Li{sub 1.2}Mn{sub 1.8}O{sub 4} thin film electrodes operated at 3 V/Li{sup +}/Li are studied by means of X-ray photoelectron spectroscopy (XPS), mainly on the basis of the evolution of the Mn2p XPS peak during the electrode cycling. The analysis of this core peak has long been debated in literature given its complex character. Based on manganese oxide references, MnO (Mn{sup 2+}), Mn{sub 2}O{sub 3}(Mn{sup 3+}) and Li{sub 2}MnO{sub 3}(Mn{sup 4+}), we propose a deconvolution method to identify each Mn oxidation state. This method is then used for the deconvolution of Mn2p XPS peaks of bulk lithium-rich spinels Li{sub 1+x}Mn{sub 2-x}O{sub 4} (0 ≤ x ≤ 0.25) for validation before proceeding to the study of cycled Li{sub 1.2}Mn{sub 1.8}O{sub 4} thin film electrodes. Electrochemical measurements exhibit significant capacity loss during the first cycle. Based on XPS analyses, this phenomenon could be explained by mechanical breakup of parts of the electrode. A stable behavior during subsequent cycles is then observed. The presence of Mn{sup 2+} species (XPS) at the most top surface of the electrode and the significant polarization observed during the discharge illustrate the kinetical limitation of the two-phase reaction, despite the reduced thickness of the electrode material.

Comparison of the equivalent width, the autocorrelation width, and the variance as figures of merit for XPS narrow scans

Energy Technology Data Exchange (ETDEWEB)

Singh, Bhupinder [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States); Velázquez, Daniel; Terry, Jeff [Department of Physics, Illinois Institute of Technology, Chicago, IL 60616 (United States); Linford, Matthew R., E-mail: mrlinford@chem.byu.edu [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States)

2014-12-15

Highlights: • We apply the equivalent and autocorrelation widths and variance to XPS narrow scans. • This approach is complementary to traditional peak fitting methods. • It is bias free and responsive to subtle chemical changes in spectra. • It has the potential for machine interpretation of spectra and quality control. • It has the potential for analysis of complex spectra and tracking charging/artifacts. - Abstract: X-ray photoelectron spectroscopy (XPS) is widely used in surface and materials laboratories around the world. It is a near surface technique, providing detailed chemical information about samples in the form of survey and narrow scans. To extract the maximum amount of information about materials it is often necessary to peak fit XPS narrow scans. And while indispensable to XPS data analysis, even experienced practitioners can struggle with their peak fitting. In our previous publication, we introduced the equivalent width (EW{sub XPS}) as both a possible machine automated method, one that requires less expert judgment for characterizing XPS narrow scans, and as an approach that may be well suited for the analysis of complex spectra. The EW{sub XPS} figure of merit was applied to four different data sets. However, as previously noted, other width functions are also regularly employed for analyzing functions. Here we evaluate two other width functions for XPS narrow scan analysis: the autocorrelation width (AW{sub XPS}) and the variance (σ{sub XPS}{sup 2}). These widths were applied to the same four sets of spectra studied before: (a) four C 1s narrow scans of ozone-treated carbon nanotubes (CNTs) (EW{sub XPS}: ∼2.11–2.16 eV, AW{sub XPS}: ∼3.9–4.1 eV, σ{sub XPS}{sup 2}: ∼5.0–5.2 eV, and a modified form of σ{sub XPS}{sup 2}, denoted σ{sub XPS}{sup 2*}: ∼6.3–6.8 eV), (b) silicon wafers with different oxide thicknesses (EW{sub XPS}: ∼1.5–2.9 eV, AW{sub XPS}: ∼2.28–4.9, and σ{sub XPS}{sup 2}: ∼0.7–4.9 eV), (iii

Análise comparativa entre a refração clínica subjetiva e a automatizada obtida por sensor de frentes de onda

OpenAIRE

Freitas,Wilson de; Melo Júnior,Luiz Alberto Soares; Schor,Paulo; Campos,Mauro

2007-01-01

OBJETIVO: Avaliar e comparar os resultados obtidos da refração estática clínica com a obtida por sensor de frentes de onda. MÉTODOS: Estudo prospectivo, não seqüencial, de 279 olhos de 147 pacientes. Todos os pacientes foram examinados sob cicloplegia. Primeiro realizamos a refração clínica e a seguir a automatizada por sensor de frentes de onda. Os dados refracionais obtidos foram decompostos para análise vetorial. Foram analisados separadamente os dados de um olho por paciente e dos dois ol...

Loss of residual monomer from resilient lining materials processed by different methods = Perda de monômero residual de reembasadores resilientes processados por diferentes métodos

Directory of Open Access Journals (Sweden)

León, Blanca Liliana Torres

2008-01-01

Full Text Available Objetivo: Avaliar o monômero residual liberado de materiais resilientes para reembasamento polimerizados por diferentes métodos. Metodologia: Dois materiais foram testados: Ever-Soft polymerizado por banho quente de água ou por energia de microondas, e Light Liner polimerizado quimicamente e por luz visível (polimerização dual. O monômero residual liberado foi mensurado em 12 espécimes (40x10x0,3mm fabricados com cada material e método de polimerização. Os espécimes foram armazenados em água destilada por 168 horas a 37ºC, e analisados diariamente por espectrometria ultravioleta (Light Liner: 204nm, Ever-Soft: 206nm. Os dados foram analisados por ANOVA de fator único e teste de Bonferroni (a=0,05. O monômero residual liberado em relação ao tempo foi determinado por análise de regressão polinomial. Resultados: O monômero residual liberado em 168 horas do teste (µg/cm2 em espécimes polimerizados por banho de água quente (0,27±0,01µg/cm2 foi significativamente maior (P < 0,05 que em espécimes processados por energia de microondas (0,25±0,02µg/cm2. Ever-Soft mostrou uma redução na liberação de monomer residual com o tempo, tendendo a se estabilizar em 96 horas. Light Liner continuou a liberar monômero com o tempo. Conclusão: Ever-Soft pode ser polimerizado por energia de microondas. Os valores de monômero residual liberado foram baixos, e os níveis de monômero diminuíram com o tempo

Surface functional group characterization using chemical derivatization X-ray photoelectron spectroscopy (CD-XPS)

Energy Technology Data Exchange (ETDEWEB)

Jagst, Eda

2011-03-18

Chemical derivatization - X-ray photolectron spectroscopy (CD-XPS) was applied successfully in order to determine different functional groups on thin film surfaces. Different amino group carrying surfaces, prepared by spin coating, self-assembly and plasma polymerization, were successfully investigated by (XPS) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. Amino groups were derivatized with the widely used primary amino group tags, pentafluorobenzaldehyde (PFB) and 4-(trifluoromethyl)-benzaldehyde (TFBA), prior to analysis. Primary amino group quantification was then carried out according to the spectroscopical data. Self-assembled monolayers (SAMs) of different terminal groups were prepared and investigated with XPS and spectra were compared with reference surfaces. An angle resolved NEXAFS measurement was applied to determine the orientation of SAMs. Plasma polymerized allylamine samples with different duty cycle, power and pressure values were prepared in order to study the effects of external plasma parameters on the primary amino group retention. CD-XPS was used to quantify the amino groups and experiments show, that the milder plasma conditions promote the retention of amino groups originating from the allylamine monomer. An interlaboratory comparison of OH group determination on plasma surfaces of polypropylene treated with oxygen plasma, was studied. The surfaces were investigated with XPS and the [OH] amount on the surfaces was calculated. (orig.)

XPS - an essential tool in biomaterial research

International Nuclear Information System (INIS)

StJohn, H.A.W.; Greisser, H.J.

1999-01-01

Full text: Increased life expectancy has markedly enhanced the need for biomedical devices to combat life-threatening conditions (e.g., pacemakers, artificial blood vessels) or improve the quality of life (e.g., intraocular lenses, artificial ligaments, contact lenses). While the biomedical device industry has delivered remarkable benefits, many existing and emerging needs and applications are not adequately met with existing synthetic materials. Depending on the application, a biomaterial needs to meet a number of requirements to be 'biocompatible', such as appropriate mechanical properties, transparency, resistance to enzymatic degradation, and appropriate biological responses by the host environment. Surface science and surface analysis plays a key role in understanding and optimizing the molecular interfacial interactions between synthetic materials surfaces and biological media which lead to biological responses to implants. Many biological molecules such as proteins and lipids have surfactant activity and respond to interfaces on contact. Thus, an important part of achieving 'biocompatibility' is to produce an appropriate surface chemical composition that avoids undesirable biological consequences triggered by biological molecules recognizing a 'foreign' material interface. XPS surface analysis has proved uniquely suitable for studying several aspects of biomaterials. In order to interpret biological responses in terms of surface chemistry, it is essential that the surface be well characterized. However, for polymers this can be quite a challenge due to the inherent mobility of polymer chains. For instance, polyurethanes present a surface chemistry that differs from the 'bulk' chemistry. It is often desirable to utilize a bulk material with desirable bulk properties and improve its biocompatibility by the application of a surface modification or a thin coating. XPS has been used to verify the intended coating chemistry and the uniformity of thin coatings. On

XPS - an essential tool in biomaterial research

Energy Technology Data Exchange (ETDEWEB)

StJohn, H.A.W.; Greisser, H.J. [Commonwealth Scientific and Industrial Research Organization (CSIRO), Clayton, VIC (Australia). Molecular Science

1999-12-01

Full text: Increased life expectancy has markedly enhanced the need for biomedical devices to combat life-threatening conditions (e.g., pacemakers, artificial blood vessels) or improve the quality of life (e.g., intraocular lenses, artificial ligaments, contact lenses). While the biomedical device industry has delivered remarkable benefits, many existing and emerging needs and applications are not adequately met with existing synthetic materials. Depending on the application, a biomaterial needs to meet a number of requirements to be `biocompatible`, such as appropriate mechanical properties, transparency, resistance to enzymatic degradation, and appropriate biological responses by the host environment. Surface science and surface analysis plays a key role in understanding and optimizing the molecular interfacial interactions between synthetic materials surfaces and biological media which lead to biological responses to implants. Many biological molecules such as proteins and lipids have surfactant activity and respond to interfaces on contact. Thus, an important part of achieving `biocompatibility` is to produce an appropriate surface chemical composition that avoids undesirable biological consequences triggered by biological molecules recognizing a `foreign` material interface. XPS surface analysis has proved uniquely suitable for studying several aspects of biomaterials. In order to interpret biological responses in terms of surface chemistry, it is essential that the surface be well characterized. However, for polymers this can be quite a challenge due to the inherent mobility of polymer chains. For instance, polyurethanes present a surface chemistry that differs from the `bulk` chemistry. It is often desirable to utilize a bulk material with desirable bulk properties and improve its biocompatibility by the application of a surface modification or a thin coating. XPS has been used to verify the intended coating chemistry and the uniformity of thin coatings. On

Speciation of uranium in minerals by Sem, Tem, μ-PIXE, XPS and XAFS

International Nuclear Information System (INIS)

Toshihiko Ohnuki; Hiroshi Isobe; Tomihiro Kamiya; Takuro Sakai; Takashi Murakami

2001-01-01

Many kinds of electromagnetic waves and particle beams are used as analytical probes for the investigation of uranium-mineralogy and speciation. The representatives of the probes are SEM, TEM, μ-PIRE, XPS and XAFS. Each of these analytical probes has its own advantages and disadvantages. We have performed studies to compare the advantages and disadvantages on the basis of the analysis of the distribution and speciation of U containing rock samples collected at the Koongarra uranium deposit, Australia. The spatial resolutions of the probes are in the order of TEM>SEM, μ-PIXE>XFAS, XPS. The lower detection limits of the probes are in the order of μ-PIXE< TEM, SEM< XFAS, XPS. Oxidation state of U was determined by XFAS and XPS. These results indicate that combination of the above probes can give us sufficient data on U speciation not only in natural rock samples but in solid samples obtained in the laboratory. (authors)

Combined PIXE and XPS analysis on republican and imperial Roman coins

International Nuclear Information System (INIS)

Dacca, A.; Prati, P.; Zucchiatti, A.; Lucarelli, F.; Mando, P.A.; Gemme, G.; Parodi, R.; Pera, R.

2000-01-01

A combined PIXE and XPS analysis has been performed on a few Roman coins of the republican and imperial age. The purpose was to investigate via XPS the nature and extent of patina in order to be capable of extracting PIXE data relative to the coins bulk. The inclusion of elements from the surface layer, altered by oxidation and inclusion, is a known source of uncertainty in PIXE analyses of coins, performed to assess the composition and the provenance

Characterization of fossil remains using XRF, XPS and XAFS spectroscopies

International Nuclear Information System (INIS)

Zougrou, I M; Katsikini, M; Pinakidou, F; Paloura, E C; Brzhezinskaya, M; Papadopoulou, L; Vlachos, E; Tsoukala, E

2016-01-01

Synchrotron radiation micro-X-Ray Fluorescence (μ-XRF), X-ray photoelectron (XPS) and X-ray Absorption Fine Structure (XAFS) spectroscopies are applied for the study of paleontological findings. More specifically the costal plate of a gigantic terrestrial turtle Titanochelon bacharidisi and a fossilized coprolite of the cave spotted hyena Crocuta crocuta spelaea are studied. Ca L 2,3 -edge NEXAFS and Ca 2p XPS are applied for the identification and quantification of apatite and Ca containing minerals. XRF mapping and XAFS are employed for the study of the spatial distribution and speciation of the minerals related to the deposition environment. (paper)

Representações sociais sobre história por jovens e adultos

Directory of Open Access Journals (Sweden)

Carina Cavaletti de Carvalho Pedroso

2014-08-01

Full Text Available A pesquisa teve por objetivos analisar as representações sociais sobre História por alunos da Educação de Jovens e Adultos e compreender como esses estudantes se percebem inseridos na História. Participaram da pesquisa sessenta e dois alunos do 3º ano do Ensino Médio, modalidade EJA, de escola pública do Estado de São Paulo. Os dados foram coletados pela pesquisadora, por meio de questionário semiestruturado, e foram analisados pela técnica de análise de conteúdo. Os resultados indicam que os participantes representam história como disciplina escolar construída por grandes heróis, ignorando sua participação efetiva na mesma enquanto sujeitos históricos. Esses jovens e adultos apresentam uma concepção que se aproxima da perspectiva tradicional da História, isto é, de uma história essencialmente política e voltada para os grandes acontecimentos. Os resultados sugerem, ainda, que as representações sociais sobre História estariam relacionadas a uma permanência de práticas pouco problematizadoras, presentes na escola dos pesquisados.

A visibilidade dos esportes e jogos por meio da filatelia brasileira

Directory of Open Access Journals (Sweden)

Júlio César Penereiro

2013-12-01

Full Text Available Este artigo trata da divulgação dos esportes e jogos por meio das imagens impressas nos selos postais. Os selos comemorativos podem ser um poderoso meio de divulgação científica para sensibilizar as sociedades, de um modo geral, sobre a importância das pesquisas científicas que foram realizadas, por exemplo, no campo dos esportes. Foram analisados todos os selos brasileiros emitidos entre 1843 e 2010, separando e classificando aqueles com conotações nos esportes. Apresenta-se uma estatística da distribuição dos selos postais segundo as várias modalidades esportivas e a descrição de alguns deles, além de uma proposta do uso desse rico material no ensino do esporte, e para uma maior divulgação do patrimônio esportivo brasileiro.

Round robin: Quantitative lateral resolution of PHI XPS microprobes Quantum 2000/Quantera SXM

International Nuclear Information System (INIS)

Scheithauer, Uwe; Kolb, Max; Kip, Gerard A.M.; Naburgh, Emile; Snijders, J.H.M.

2016-01-01

Highlights: • The quantitative lateral resolution of 7 PHI XPS microprobes has been estimated in a round robin. • An ellipsoidally shaped quartz crystal monochromatizes the Alkα radiation and refocuses it from the Al anode to the sample surface. • The long tail contributions of the X-ray beam intensity distribution were measured using a new and innovative approach. • This quantitative lateral resolution has a significantly larger value than the nominal X-ray beam diameter. • The quantitative lateral resolution follows a trend in time: The newer the monochromator so much the better the quantitative lateral resolution. - Abstract: The quantitative lateral resolution is a reliable measure for the quality of an XPS microprobe equipped with a focused X-ray beam. It describes the long tail contributions of the X-ray beam intensity distribution. The knowledge of these long tail contributions is essential when judging on the origin of signals of XPS spectra recorded on small-sized features. In this round robin test the quantitative lateral resolution of 7 PHI XPS microprobes has been estimated. As expected, the quantitative lateral resolution has significantly larger values than the nominal X-ray beam diameter. The estimated values of the quantitative lateral resolution follow a trend in time: the newer the monochromator of an XPS microprobe so much the better the quantitative lateral resolution.

Round robin: Quantitative lateral resolution of PHI XPS microprobes Quantum 2000/Quantera SXM

Energy Technology Data Exchange (ETDEWEB)

Scheithauer, Uwe, E-mail: scht.uhg@googlemail.com [82008 Unterhaching (Germany); Kolb, Max, E-mail: max.kolb@airbus.com [Airbus Group Innovations, TX2, 81663 Munich (Germany); Kip, Gerard A.M., E-mail: G.A.M.Kip@utwente.nl [Universiteit Twente, MESA+ Nanolab, Postbus 217, 7500AE Enschede (Netherlands); Naburgh, Emile, E-mail: e.p.naburgh@philips.com [Materials Analysis, Philips Innovation Services, High Tech Campus 11, 5656 AE Eindhoven (Netherlands); Snijders, J.H.M., E-mail: j.h.m.snijders@philips.com [Materials Analysis, Philips Innovation Services, High Tech Campus 11, 5656 AE Eindhoven (Netherlands)

2016-07-15

Highlights: • The quantitative lateral resolution of 7 PHI XPS microprobes has been estimated in a round robin. • An ellipsoidally shaped quartz crystal monochromatizes the Alkα radiation and refocuses it from the Al anode to the sample surface. • The long tail contributions of the X-ray beam intensity distribution were measured using a new and innovative approach. • This quantitative lateral resolution has a significantly larger value than the nominal X-ray beam diameter. • The quantitative lateral resolution follows a trend in time: The newer the monochromator so much the better the quantitative lateral resolution. - Abstract: The quantitative lateral resolution is a reliable measure for the quality of an XPS microprobe equipped with a focused X-ray beam. It describes the long tail contributions of the X-ray beam intensity distribution. The knowledge of these long tail contributions is essential when judging on the origin of signals of XPS spectra recorded on small-sized features. In this round robin test the quantitative lateral resolution of 7 PHI XPS microprobes has been estimated. As expected, the quantitative lateral resolution has significantly larger values than the nominal X-ray beam diameter. The estimated values of the quantitative lateral resolution follow a trend in time: the newer the monochromator of an XPS microprobe so much the better the quantitative lateral resolution.

EXTRAÇÃO DE ISÓTOPOS ESTÁVEIS DE CO2 POR SUBLIMAÇÃO PARA DETERMINAÇÃO DO BALANÇO DE CARBONO DA BACIA AMAZÔNICA

Directory of Open Access Journals (Sweden)

Stephane Palma Crispim

2017-05-01

Full Text Available Apresentamos neste trabalho a implementação de um sistema de extração de isótopos estáveis de CO2 por sublimação, que esta sendo aplicado em amostras coletadas em dois diferentes pontos Rio Branco e Alta Floresta, localidades escolhidas através de estudos para a realização do balanço de carbono na Amazônia. As coletas são feitas por meio de aviões de pequeno porte, utilizando um sistema semiautomático desenvolvido pelo GMD/ESRL/NOAA que posteriormente é analisado no laboratório localizado no Instituto Nacional de Pesquisas Espaciais em São José dos Campos e encaminhado para a realização das extrações. As amostras contendo apenas CO2 puro, são seladas em chama e encaminhadas para a Holanda onde serão analisados δ¹³C e Δ17O.

XPS and NEXAFS study of tyrosine-terminated propanethiol assembled on gold

CERN Document Server

Petoral, R M

2003-01-01

Tyrosine-terminated propanethiol (TPT), tyrosine linked to 3-mercaptopropionic acid through an amide bond, is adsorbed to gold surfaces. The adsorbates are characterized by means of X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). XPS is used to investigate the chemical binding and electronic structure of the monolayer. Strong molecular binding of the tyrosine derivative on the gold surface through the sulfur atom is attained. Angle-dependent XPS results shows that TPT molecules are oriented with the sulfur atoms molecularly oriented close to the gold surface and that the phenol moiety is oriented away from the gold surface. Average orientation of the adsorbate on gold is deduced using the NEXAFS results. It shows that the main molecular axis is tilted approximately 38 deg. relative to the Au surface normal. The ring plane of the phenol moiety exhibits a preferential orientation with an average tilt angle of the normal of the ring plane from the surfa...

Surface chemical characterization of PM{sub 10} samples by XPS

Energy Technology Data Exchange (ETDEWEB)

Atzei, Davide, E-mail: datzei@unica.it [Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Complesso Universitario di Monserrato, S.S. 554 Bivio per Sestu, I-09042 Monserrato, Cagliari (Italy); Fantauzzi, Marzia; Rossi, Antonella [Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Complesso Universitario di Monserrato, S.S. 554 Bivio per Sestu, I-09042 Monserrato, Cagliari (Italy); Fermo, Paola [Dipartimento di Chimica, Università degli Studi Milano, Via Golgi 19, I-20133 Milano (Italy); Piazzalunga, Andrea [Dipartimento di Chimica, Università degli Studi Milano, Via Golgi 19, I-20133 Milano (Italy); Dipartimento di Scienze dell’Ambiente e del territorio, Università degli Studi di Milano-Bicocca, Piazza della Scienza 1, I-20122 Milano (Italy); Valli, Gianluigi; Vecchi, Roberta [Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, I-20133 Milano (Italy)

2014-07-01

Samples of particulate matter (PM) collected in the city of Milan during wintertime were analyzed by X-ray photoelectron spectroscopy (XPS), thermal optical transmittance (TOT), ionic chromatography (IC) and X-ray fluorescence (XRF) in order to compare quantitative bulk analysis and surface analysis. In particular, the analysis of surface carbon is here presented following a new approach for the C1s curve fitting aiming this work to prove the capability of XPS to discriminate among elemental carbon (EC) and organic carbon (OC) and to quantify the carbon-based compounds that might be present in the PM. Since surface of urban PM is found to be rich in carbon it is important to be able to distinguish between the different species. XPS results indicate that aromatic and aliphatic species are adsorbed on the PM surface. Higher concentrations of (EC) are present in the bulk. Also nitrogen and sulfur were detected on the surfaces and a qualitative and quantitative analysis is provided. Surface concentration of sulfate ion is equal to that found by bulk analysis; moreover surface analysis shows an additional signal due to organic sulfur not detectable by the other methods. Surface appears to be also enriched in nitrogen.

XPS Studies of LSCF Interfaces after Cell Testing

Directory of Open Access Journals (Sweden)

Gianfranco DiGiuseppe

2018-01-01

Full Text Available The motivation of this investigation is to explore the possibility of using the depth profile capability of XPS to study interfaces after SOFC button cell testing. The literature uses XPS to study various cathode materials but has devoted little to the understanding of various cathode interfaces especially after testing. In this work, an SOFC button cell is first tested, and then, the LSCF cathode, barrier layer, and electrolyte are sputtered away to study the behavior of different interfaces. This work has shown that some elements have moved into other layers of the SOFC cell. It is argued that the migration of the elements is partly due to a redeposition mechanism after atoms are sputtered away, while the rest is due to interdiffusion between the SDC and YSZ layers. However, additional work is needed to better understand the mechanism by which atoms move around at different interfaces. The cell electrochemical performance is also discussed in some details but is not the focus.

The use of XPS and i.r. spectroscopy in zinc mineral flotation studies

International Nuclear Information System (INIS)

Garbassi, F.; Morabini, A.; Cozza, C.

1985-01-01

In this work, XPS (X-ray photoelectron spectroscopy) is applied to the study of the interaction of dodecylamine acetate with smithsonite ZnCo 3 , in relation with the problem of flotation of the mineral. This study confirms that, in spite of ultra-high conditions during analysis XPS is a technique offering a very valuable contribution to the elucidation of mineral flotation problems

APS- and XPS-investigations of vanadium, vanadium carbide and graphite

Energy Technology Data Exchange (ETDEWEB)

Bradshaw, A M; Krause, U [Technische Univ. Muenchen (F.R. Germany). Inst. fuer Physikalische Chemie und Theoretische Chemie

1975-11-01

Soft X-ray appearance potential spectroscopy (APS) and X-ray photoelectron spectroscopy (XPS) have been used to study vanadium, vanadium carbide, and graphite. The chemical shifts for vanadium carbide with respect to metallic vanadium and graphite are compared for the two methods. The Csub(K) structure in APS and the valence band in XPS for vanadium carbide show good agreement with the band structure calculations of Neckel and co-workers. Using the band structure calculations of Painter et al. it is also shown how the multi-peak structure in the APS spectrum of graphite is possibly due to density of states effects. It would therefore appear that plasmon coupling plays only a minor role.

XPS and bioactivity study of the bisphosphonate pamidronate adsorbed onto plasma sprayed hydroxyapatite coatings

International Nuclear Information System (INIS)

McLeod, Kate; Kumar, Sunil; Smart, Roger St.C.; Dutta, Naba; Voelcker, Nicolas H.; Anderson, Gail I.; Sekel, Ron

2006-01-01

This paper reports the use of X-ray photoelectron spectroscopy (XPS) to investigate bisphosphonate (BP) adsorption onto plasma sprayed hydroxyapatite (HA) coatings commonly used for orthopaedic implants. BPs exhibit high binding affinity for the calcium present in HA and hence can be adsorbed onto HA-coated implants to exploit their beneficial properties for improved bone growth at the implant interface. A rigorous XPS analysis of pamidronate, a commonly used nitrogenous BP, adsorbed onto plasma sprayed HA-coated cobalt-chromium substrates has been carried out, aimed at: (a) confirming the adsorption of this BP onto HA; (b) studying the BP diffusion profile in the HA coating by employing the technique of XPS depth profiling; (c) confirming the bioactivity of the adsorbed BP. XPS spectra of plasma sprayed HA-coated discs exposed to a 10 mM aqueous BP solution (pamidronate) for periods of 1, 2 and 24 h showed nitrogen and phosphorous photoelectron signals corresponding to the BP, confirming its adsorption onto the HA substrate. XPS depth profiling of the 2 h BP-exposed HA discs showed penetration of the BP into the HA matrix to depths of at least 260 nm. The bioactivity of the adsorbed BP was confirmed by the observed inhibition of osteoclast (bone resorbing) cell activity. In comparison to the HA sample, the HA sample with adsorbed BP exhibited a 25-fold decrease in primary osteoclast cells

Quantitative XPS analysis of thin iron-oxide films

DEFF Research Database (Denmark)

Graat, P.C.J.; Somers, Marcel A. J.

1997-01-01

Over the last decade Tougaard et al. (see e.g. Ref. 1) provided a formalism to calculate the contribution of inelastically scattered electrons to an XPS or AES spectrum. In that formalism it was assumed that the signal electrons move along straight lines to the surface. Recently, Werner et al. pr...

Surface studies on uranium monocarbide using XPS and SIMS

International Nuclear Information System (INIS)

Asuvathraman, R.

1995-01-01

The air-exposed surfaces of sintered and arc-melted UC samples were examined by XPS and SIMS. XPS results indicate that the surface is covered with a very thin layer of UO 2 mixed with free carbon, which would have formed along with the oxide during the reaction between UC and oxygen or moisture. From the SIMS depth profile of oxygen, the thickness of the oxide layer is found to be approximately 10 nm. The SIMS oxygen images of the surface as a function of etching time reveal that the surface of UC consists of a top layer of adsorbed moisture/oxygen; this contamination layer is followed by a layer containing uranium oxide, uranium hydroxide and free carbon and then grain boundary oxide and finally bulk UC. The behaviour of sintered and arc-melted samples is similar. ((orig.))

XPS and surface resistivity measurements of plasma - treated FEP co-polymer

International Nuclear Information System (INIS)

Pitrus, R.K.; Brack, N.; Liesegang, J.; Pigram, P.J.

2002-01-01

Full text: Fluorinated polymers such as fluorinated ethylene propylene (FEP) and poly(tetrafluoroethylene) (PTFE) play an important role in many applications due to their many desirable properties such as chemical resistivity, inertness, electrical stability and low dielectric constant; however, one disadvantage of fluorinated polymers is their extreme surface hydrophobicity. Previous studies show that plasma treatment will modify the surface by increasing the surface free energy and also offer a rapid and convenient method for pre-treating the polymers for many purposes. This paper, through resistivity and XPS (x-ray photoelectron spectroscopy) measurements, attempts to discover basic effects of such plasma treatment. Fluorinated ethylene propylene (FEP) co-polymer film of (0.05) mm thickness (obtained commercially) and with the following structure (CF 2 -CF 2 )-(CF(CF 3 )CF 2 )- was used. A suitable cleaning procedure was used to remove adventitious carbon from the surface. XPS has been used to study FEP film properties. The spectra of XPS were analyzed with the main focus on carbon and fluorine as they compose the elemental component of FEP film. A value of 2.05 was obtained for the F/C ratio, which is slightly higher than the theoretical F/C value estimated from the chemical structure of FEP (F/C 2). The clean film was then air plasma treated (pressure 10 -1 torr and power 30W) for various treatment times to produce a higher energy fluoropolymer surface. XPS studies investigated changes to the polymer surface and determined that oxidation occurs on the FEP surface. The oxidation reactions on the FEP surface form oxygen functional groups such as C-O and C=O groups. The results also show that the percentage of CF 2 and CF 3 in the co-polymer surface decreased with exposure time and the percentage of CF, C-C, C-O and C=O increased. There is a sharp decrease in F/C ratio and increase in O/C ratio. In addition to XPS, the resistivity of FEP-film was measured by a

XPS and NEXAFS analysis of dimethyl sulfide adsorbed on the Rh(PVP) nanoparticle surface

International Nuclear Information System (INIS)

Niwa, Hironori; Ogawa, Satoshi; Yagi, Shinya; Kutluk, Galif

2010-01-01

We have studied the adsorption reaction of dimethyl sulfide (DMS: (CH 3 ) 2 S) on the surface of Rh(PVP) nanoparticles by using AFM, XPS and NEXAFS techniques. The AFM images show the degree of dispersion of the Rh(PVP) nanoparticles depends on the amount of them. The in-situ XPS results indicate that the dissociation reaction of DMS into atomic S does not depend upon the existence of the Rh(PVP) nanoparticles. The NEXAFS results show that there is a strong chemical bonding between Rh(PVP) nanoparticle and atomic S. The ex-situ XPS results show the atomic S adsorbed on the Rh(PVP) nanoparticles partially desorb by exposing to the air. (author)

Upgrade of the Surface Spectrometer at NEPOMUC for PAES, XPS and STM Investigations

Science.gov (United States)

Zimnik, S.; Lippert, F.; Hugenschmidt, C.

2014-04-01

The characterization of the elemental composition of surfaces is of great importance for the understanding of many surface processes, such as surface segregation or oxidation. Positron-annihilation-induced Auger Electron Spectroscopy (PAES) is a powerful technique for gathering information about the elemental composition of only the topmost atomic layer of a sample. The upgraded surface spectrometer at NEPOMUC (NEtron induced POsitron source MUniCh) enables a comprehensive surface analysis with the complementary techniques STM, XPS and PAES. A new X-ray source for X-ray induced photoelectron spectroscopy (XPS) was installed to gather additional information on oxidation states. A new scanning tunneling microscope (STM) is used as a complementary method to investigate with atomic resolution the surface electron density. The combination of PAES, XPS and STM allows the characterization of both the elemental composition, and the surface topology.

XPS studies of ceramics with pyrochlore structure for radioactive wastes disposal

International Nuclear Information System (INIS)

Teterin, Yu.A.; Vukchevich, L.; Ivanov, K.E.; Utkin, I.O; Teterin, A. Yu.; Maslakov, K.I.; Yudintseva, T.S.; Yudintsev, S.V.; Stefanovsky, S.V.; Lapina, M.I. . E-mail address of corresponding author: vukas@rc.pmf.cg.ac.yu; Vukchevich, L.)

2005-01-01

X-ray photoelectron spectroscopy (XPS) study of ceramics CaThSn 2 O 7 and CaThZr 2 O 7 with pyrochlore structure used as matrixes for the disposal of long lived high level radioactive wastes was done. On the basis of the XPS parameters of the core and outer electrons in the binding energy range 0 - 1000 eV the oxidation states of the included metals were determined, quantitative elemental and ionic analysis was carried out and a conclusion on the monophaseness of the studied samples was drawn. The obtained data agree with the X-ray diffraction and scanning electron microscopy results. (author)

Theoretical modeling of the uranium 4f XPS for U(VI) and U(IV) oxides

Energy Technology Data Exchange (ETDEWEB)

Bagus, Paul S. [Department of Chemistry, University of North Texas, Denton, Texas 76203-5017 (United States); Nelin, Connie J. [Consulting and Services, 6008 Maury' s Trail, Austin, Texas 78730 (United States); Ilton, Eugene S. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

2013-12-28

A rigorous study is presented of the physical processes related to X-Ray photoelectron spectroscopy, XPS, in the 4f level of U oxides, which, as well as being of physical interest in themselves, are representative of XPS in heavy metal oxides. In particular, we present compelling evidence for a new view of the screening of core-holes that extends prior understandings. Our analysis of the screening focuses on the covalent mixing of high lying U and O orbitals as opposed to the, more common, use of orbitals that are nominally pure U or pure O. It is shown that this covalent mixing is quite different for the initial and final, core-hole, configurations and that this difference is directly related to the XPS satellite intensity. Furthermore, we show that the high-lying U d orbitals as well as the U(5f) orbital may both contribute to the core-hole screening, in contrast with previous work that has only considered screening through the U(5f) shell. The role of modifying the U-O interaction by changing the U-O distance has been investigated and an unexpected correlation between U-O distance and XPS satellite intensity has been discovered. The role of flourite and octahedral crystal structures for U(IV) oxides has been examined and relationships established between XPS features and the covalent interactions in the different structures. The physical views of XPS satellites as arising from shake processes or as arising from ligand to metal charge transfers are contrasted; our analysis provides strong support that shake processes give a more fundamental physical understanding than charge transfer. Our theoretical studies are based on rigorous, strictly ab initio determinations of the electronic structure of embedded cluster models of U oxides with formal U(VI) and U(IV) oxidation states. Our results provide a foundation that makes it possible to establish quantitative relationships between features of the XPS spectra and materials properties.

Theoretical modeling of the uranium 4f XPS for U(VI) and U(IV) oxides

Science.gov (United States)

Bagus, Paul S.; Nelin, Connie J.; Ilton, Eugene S.

2013-12-01

A rigorous study is presented of the physical processes related to X-Ray photoelectron spectroscopy, XPS, in the 4f level of U oxides, which, as well as being of physical interest in themselves, are representative of XPS in heavy metal oxides. In particular, we present compelling evidence for a new view of the screening of core-holes that extends prior understandings. Our analysis of the screening focuses on the covalent mixing of high lying U and O orbitals as opposed to the, more common, use of orbitals that are nominally pure U or pure O. It is shown that this covalent mixing is quite different for the initial and final, core-hole, configurations and that this difference is directly related to the XPS satellite intensity. Furthermore, we show that the high-lying U d orbitals as well as the U(5f) orbital may both contribute to the core-hole screening, in contrast with previous work that has only considered screening through the U(5f) shell. The role of modifying the U-O interaction by changing the U-O distance has been investigated and an unexpected correlation between U-O distance and XPS satellite intensity has been discovered. The role of flourite and octahedral crystal structures for U(IV) oxides has been examined and relationships established between XPS features and the covalent interactions in the different structures. The physical views of XPS satellites as arising from shake processes or as arising from ligand to metal charge transfers are contrasted; our analysis provides strong support that shake processes give a more fundamental physical understanding than charge transfer. Our theoretical studies are based on rigorous, strictly ab initio determinations of the electronic structure of embedded cluster models of U oxides with formal U(VI) and U(IV) oxidation states. Our results provide a foundation that makes it possible to establish quantitative relationships between features of the XPS spectra and materials properties.

ISS Assessment of the Influence of Nonpore Surface in the XPS Analysis of Oil-Producing Reservoir Rocks

Science.gov (United States)

Leon; Toledo; Araujo

1997-08-15

The application of X-ray photoelectron spectroscopy (XPS) to oil-producing reservoir rocks is new and has shown that pore surface concentrations can be related to rock wettability. In the preparation of fresh fractures of rocks, however, some nonpore surface corresponding to the connection regions in the rocks is created and exposed to XPS. To assess the potential influence of this nonpore surface in the XPS analysis of rocks here we use ion scattering spectroscopy (ISS), which has a resolution comparable to the size of the pores, higher than that of XPS, with an ion gun of He+ at maximum focus. Sample charging effects are partially eliminated with a flood gun of low energy electrons. All the ISS signals are identified by means of a formula which corrects any residual charging on the samples. Three rock samples are analyzed by XPS and ISS. The almost unchanged ISS spectra obtained at different points of a given sample suggest that the nonpore surface created in the fracture process is negligibly small, indicating that XPS data, from a larger surface spot, represents the composition of true pore surfaces. The significant changes observed in ISS spectra from different samples indicate that ISS is sample specific. Copyright 1997Academic Press

XPS studies of the oxide formed on pure Ti

International Nuclear Information System (INIS)

Cremery, P.; David, D.; Beranger, G.; Oviedo, C.; Garcia, E.A.

1980-01-01

The XPS technique was used to study titanium samples oxidized at 200 ton of pure oxigen at different times and temperatures with the aim of producing variable oxide thicknesses. The thicknesses of different oxigen layers were determined by the nuclear reaction O 16 (d,p) O 17 *. (author) [pt

Charge compensation and binding energy referencing in XPS analysis

International Nuclear Information System (INIS)

Metson, J.B.

1999-01-01

Full text: The past decade has seen a number of significant advances in the capabilities of commercial X-ray Photoelectron spectrometers. Of note have been the near universal adoption of monochromatised X-ray sources, very useful advances in spatial resolution, particularly in spectroscopy, and radical developments in sample handling and automation. However one of the most significant advances has been the development of several relatively new concepts in charge compensation. Throughout the evolution of XPS, the ability to compensate for surface charging and accurately determine binding energies, particularly with electrically inhomogenous samples, has remained one of the most intractable problems. Beginning perhaps with the Kratos, 'in the lens' electrostatic mirror/electron source coupled with a magnetic snorkel lens, a number of concepts have been advanced which take a quite different conceptual approach to charge compensation. They differ in a number of quite fundamental ways to the electron flood type compensators widely used and absolutely essential with instruments based on monochromatised sources. The concept of the local return of secondary electrons to their point of emission, largely negates the problems associated with differential charging across different regions of the surface, and suggests the possibility of overcoming one of the central limitations of XPS, that is the inability to compare absolute binding energies of species in different electrical as well as chemical environments. The general status of charge compensation and the use of internal binding energy references in XPS will be reviewed, along with some practical examples of where these techniques work, and where there is clearly still room for further development. Copyright (1999) Australian X-ray Analytical Association Inc

Quantitative XPS analysis of high Tc superconductor surfaces

International Nuclear Information System (INIS)

Jablonski, A.; Sanada, N.; Suzuki, Y.; Fukuda, Y.; Nagoshi, M.

1993-01-01

The procedure of quantitative XPS analysis involving the relative sensitivity factors is most convenient to apply to high T c superconductor surfaces because this procedure does not require standards. However, a considerable limitation of such an approach is its relatively low accuracy. In the present work, a proposition is made to use for this purpose a modification of the relative sensitivity factor approach accounting for the matrix and the instrumental effects. The accuracy of this modification when applied to the binary metal alloys is 2% or better. A quantitative XPS analysis was made for surfaces of the compounds Bi 2 Sr 2 CuO 6 , Bi 2 Sr 2 CaCu 2 O 8 , and YBa 2 Cu 3 O Y . The surface composition determined for the polycrystalline samples corresponds reasonably well to the bulk stoichiometry. Slight deficiency of oxygen was found for the Bi-based compounds. The surface exposed on cleavage of the Bi 2 Sr 2 CaCu 2 O 8 single crystal was found to be enriched with bismuth, which indicates that the cleavage occurs along the BiO planes. This result is in agreement with the STM studies published in the literature

Direct formation of a polyamide on Ag(111): Joint XPS and STM studies

Energy Technology Data Exchange (ETDEWEB)

Schmid, Martin; Steinrueck, Hans-Peter; Gottfried, J. Michael [Lehrstuhl fuer Physikalische Chemie II, Universitaet Erlangen-Nuernberg (Germany); Schmitz, Christoph H.; Ikonomov, Julian; Sokolowski, Moritz [Institut fuer Physikalische und Theoretische Chemie, Universitaet Bonn (Germany)

2011-07-01

The polymer poly(p-phenylene terephthalamide) (PPTA) was synthesized on Ag(111) by co-adsorption of the reactive monomer compounds terephthaloyl chloride (TPC) and p-phenylenediamine (PPD) at 300 K. The resulting adsorbate phases were characterised by photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). A detailed study of the chemical composition and morphology revealed a complex reaction mechanism, by which the formation of amide bonds leads to folded PPTA polymer chains. According to XPS, the chloride of the TPC precursor is not released as HCl as in the bulk reaction, but remains on the surface as chemisorbed Cl or AgCl. Further temperature-programmed XPS studies of pure TPC on Ag(111) reveal that the molecule decomposes already above 130 K, forming chemisorbed Cl (or AgCl) and a phenylene-dicarbonyl species, which is presumably stabilized by the substrate. The adsorbed chlorine partially desorbs above 800 K as molecular AgCl.

De um escritor escrevente: “O amor de Pedro por João”

Directory of Open Access Journals (Sweden)

Maria Iraci Cardoso Tuzzin

2017-03-01

Full Text Available O romance O amor de Pedro por João publicado no Brasil, em 1982, e escrito durante o exílio do escritor brasileiro Tabajara Ruas (1942 é analisado a partir da relação escritor/escrita. Tal correspondência é discutida por um viés que inclui as anotações de pesquisadores, como Avelar, Silverman e Santiago, entre outros. A observação da forma, do estilo e das temáticas empregadas pelo artista aponta para a complexidade de questões referentes à profissão “escritor” em um contexto histórico pleno de cerceamento de liberdades situado entre os anos 1960 e 1980. Além disso, suscita reflexões sobre procedimentos literários experimentais em um meio social em que se ampliaram o grau e o controle da informação, apontando, deste modo, ligações entre a Literatura e a História.

Cotidiano da gravidez de risco por cardiopatia: estudo fenomenológico das relações assistenciais

Directory of Open Access Journals (Sweden)

Thaís Vasconselos Amorim

Full Text Available RESUMO Objetivo: Desvelar o cotidiano das relações assistenciais do ser-aí-mulher na gravidez de alto risco por doença cardíaca. Métodos: Pesquisa qualitativa fenomenológica. Dezessete participantes foram entrevistadas em instituição referência para risco materno e os significados expressos foram analisados à luz do pensamento de Martin Heidegger. Resultados: As mulheres significaram terem sido cobradas pelos médicos por engravidarem e; saberem que o cardiologista dá o parecer, mas o obstetra é quem vai decidir a via de parto. Conclusão: Evidenciaram-se relações assistenciais pautadas na ótica fisiopatológica de acompanhamento gestacional e invisibilidade da equipe de enfermagem junto à gestante. Se por um lado os resultados apontam a necessidade de transcender para uma relação existencial que considera a mulher como ser-aí dotada de possibilidades, por outro anuncia a importância do cuidado de enfermagem congruente às necessidades de gestantes portadoras de cardiopatia na perspectiva de se fazer percebido e anunciado pelo ser-cuidado.

XPS studies of nitrogen doping niobium used for accelerator applications

Science.gov (United States)

Yang, Ziqin; Lu, Xiangyang; Tan, Weiwei; Zhao, Jifei; Yang, Deyu; Yang, Yujia; He, Yuan; Zhou, Kui

2018-05-01

Nitrogen doping study on niobium (Nb) samples used for the fabrication of superconducting radio frequency (SRF) cavities was carried out. The samples' surface treatment was attempted to replicate that of the Nb SRF cavities, which includes heavy electropolishing (EP), nitrogen doping and the subsequent EP with different amounts of material removal. The surface chemical composition of Nb samples with different post treatments has been studied by XPS. The chemical composition of Nb, O, C and N was presented before and after Gas Cluster Ion Beam (GCIB) etching. No signals of poorly superconducting nitrides NbNx was found on the surface of any doped Nb sample with the 2/6 recipe before GCIB etching. However, in the depth range greater than 30 nm, the content of N element is below the XPS detection precision scope even for the Nb sample directly after nitrogen doping treatment with the 2/6 recipe.

XPS investigation of copper corrosion in hydro-carbonate electrolytes

Energy Technology Data Exchange (ETDEWEB)

Sieber, I.; Hildebrand, H.; Schmuki, P. [University Erlangen-Nuremberg, Martensstr.7, D-91058 Erlangen (Germany); Kaluzhina, S.A. [Voronezh State University, University Sq.1, 394006 Voronezh (Russian Federation)

2004-07-01

Problems of corrosion and effective methods of metal protection are still actual in the present days. Special interest is in copper material, which as basic component of heat exchanger constructions can corrode in contact with carbonate water. The intensity of the corrosion destruction depends on the carbon water concentration and thermal conditions in the system. The present paper provides new insights into the role of the HCO{sub 3}{sup -} - ions in the corrosion process of copper. Copper samples after anodic oxidation in 0.02 and 0.1 M NaHCO{sub 3} have been studied using XPS and SEM. The presence of carbonate compounds in the passive film in 0.1 M NaHCO{sub 3} was established by XPS analysis all over the surface. These compounds are responsible for the protective character of the passive film towards local destruction. In the 0.02 M NaHCO{sub 3} electrolyte carbonate compounds were not found at places of pit formation after multi-cycling of the sample. (authors)

ESTUDIO DE MEZCLA DE NANOPARTÍCULAS SULFURADAS Y OXIDADAS DE Mo Y DE Ni SOPORTADAS EN ALÚMINA, OBTENIDAS POR EL MÉTODO DE DESCOMPOSICIÓN TÉRMICA

Directory of Open Access Journals (Sweden)

Susana Martínez

2011-01-01

Full Text Available Se sintetizó una mezcla de nanopartículas sulfuradas y oxidadas de Mo y de Ni por el método de descomposición térmica, empleando un sistema de reflujo, dimetil disulfuro como agente sulfidizante, nonano como disolvente y una alúmina comercial que fungía como soporte. El sólido gris resultante se eliminó primero por decantación y luego por evaporación del líquido remanente bajo condiciones de vacío con el fin de evitar cambios, específicamente en las nanopartículas obtenidas. Una vez obtenidas las nanopartículas soportadas en alúmina se determinaron sus propiedades fisicoquímicas (morfología, estructura cristalina, estado de oxidación y composición elemental empleando las técnicas de HR-TEM, XPS e ICP. Los resultados de XPS y MET-HR muestran que el sólido esta conformado por nanopartículas de los metales seleccionados en sus formas oxidadas y sulfuradas tales como MoO3, MoS2, Ni2O3 y NiS, siendo la fase mayoritaria el MoO3. En los resultados no se evidenciaron fases mixtas o aleaciones de Mo y Ni.

Infarto cerebral e edema avaliação prognóstico-evolutiva por sinais neurológicos

Directory of Open Access Journals (Sweden)

Rubens José Gagliardi

1991-03-01

Full Text Available Trata-se de estudo prospectivo abrangendo 92 doentes com infarto cerebral (IC. O seguimento foi feito durante 10 dias com avaliação diária, sendo os doentes analisados por escala de notas para diferentes sinais costumeiramente pesquisados nesses casos. A metodologia foi especialmente desenvolvida no sentido de analisar exclusivamente alterações devidas ao edema oriundo da isquemia e IC. As conclusões foram obtidas por comparação isolada das médias das notas de cada sinal com a média do total das notas. Os resultados mostram que o exame da «consciência», isoladamente, é o melhor parâmetro clínico para averiguar a evolução do doente após um IC, sem outras complicações que não o edema.

Applications Performance on NAS Intel Paragon XP/S - 15#

Science.gov (United States)

Saini, Subhash; Simon, Horst D.; Copper, D. M. (Technical Monitor)

1994-01-01

The Numerical Aerodynamic Simulation (NAS) Systems Division received an Intel Touchstone Sigma prototype model Paragon XP/S- 15 in February, 1993. The i860 XP microprocessor with an integrated floating point unit and operating in dual -instruction mode gives peak performance of 75 million floating point operations (NIFLOPS) per second for 64 bit floating point arithmetic. It is used in the Paragon XP/S-15 which has been installed at NAS, NASA Ames Research Center. The NAS Paragon has 208 nodes and its peak performance is 15.6 GFLOPS. Here, we will report on early experience using the Paragon XP/S- 15. We have tested its performance using both kernels and applications of interest to NAS. We have measured the performance of BLAS 1, 2 and 3 both assembly-coded and Fortran coded on NAS Paragon XP/S- 15. Furthermore, we have investigated the performance of a single node one-dimensional FFT, a distributed two-dimensional FFT and a distributed three-dimensional FFT Finally, we measured the performance of NAS Parallel Benchmarks (NPB) on the Paragon and compare it with the performance obtained on other highly parallel machines, such as CM-5, CRAY T3D, IBM SP I, etc. In particular, we investigated the following issues, which can strongly affect the performance of the Paragon: a. Impact of the operating system: Intel currently uses as a default an operating system OSF/1 AD from the Open Software Foundation. The paging of Open Software Foundation (OSF) server at 22 MB to make more memory available for the application degrades the performance. We found that when the limit of 26 NIB per node out of 32 MB available is reached, the application is paged out of main memory using virtual memory. When the application starts paging, the performance is considerably reduced. We found that dynamic memory allocation can help applications performance under certain circumstances. b. Impact of data cache on the i860/XP: We measured the performance of the BLAS both assembly coded and Fortran

Efectos de fotodegradación propiciados por recubrimientos de TiO2 y TiO2-SiO2 obtenidos por Sol-Gel

Directory of Open Access Journals (Sweden)

Rodriguez Paez, J. E.

2008-10-01

Full Text Available Photodegradation effect is widely used for water purification this contributes to preservation and protection of environment. Titanium oxide, (TiO2, is a compound that shows up this phenomenon. TiO2 is a semiconductor which may degradate pollutants through of a oxidation process. It permit the treatment of the residual water. It this work we has conformed coatings of TiO2 y TiO2-SiO2, utilized Sol-Gel method and investigated the degradation of the blue Methylene. For this, we introduced these coatings in the blue methylene solution which was illuminated with radiation of λ=365nm to activate its photocatilist properties. The structures of the coatings were characterized using Atomic Force Microscopy (AFM and X-ray Photoelectron Spectroscopy (XPS.El efecto de fotodegradación es ampliamente utilizado para la purificación del agua, acción que contribuye a la conservación y protección del medio ambiente; el óxido de titanio (TiO2 es uno de los semiconductores que pueden degradar contaminantes mediante procesos de oxidación, lo que lo hace apto para el tratamiento de aguas residuales. En este trabajo se conformaron recubrimientos de TiO2 y TiO2-SiO2, por el método Sol-Gel, y se estudio la degradación que experimentaba una solución de azul de metileno al introducirle estos recubrimientos e iluminarlos con una radiación de λ=365nm para activar su propiedad fotocatalítica. Los recubrimientos fueron caracterizados microestructuralmente utilizando Microscopía de Fuerza Atómica (MFA y Espectroscopía de Fotoelectrones de rayos X (XPS. Los resultados obtenidos de los ensayos de fotodegradación indican que los recubrimientos con una cantidad pequeña de silicio presentan un mayor efecto de fotodegradación indicando que el silicio puede generar puntos de anclaje que facilitan las reacciones de fotocatálisis. Por otro lado, la formación de centros activos, constituidos principalmente por carbono, también contribuyeron al desarrollo de estas

Uso de medicamentos por pessoas com deficiências em áreas do estado de São Paulo

OpenAIRE

Castro,Shamyr Sulyvan; Pelicioni,Americo Focesi; Cesar,Chester Luiz Galvão; Carandina,Luana; Barros,Marilisa Berti de Azevedo; Alves,Maria Cecilia Goi Porto; Goldbaum,Moisés

2010-01-01

OBJETIVO: Analisar o consumo de medicamentos e os principais grupos terapêuticos consumidos por pessoas com deficiências físicas, auditivas ou visuais. MÉTODOS: Estudo transversal em que foram analisados dados do Inquérito Multicêntrico de Saúde no Estado de São Paulo (ISA-SP) em 2002 e do Inquérito de Saúde no Município de São Paulo (ISA-Capital), realizado em 2003. Os entrevistados que referiram deficiências foram estudados segundo as variáveis que compõem o banco de dados: área, sexo, rend...

XPS study of palladium sensitized nano porous silicon thin film

Indian Academy of Sciences (India)

Keywords. Porous silicon; passivation; palladium; oxidation; XPS. Abstract. Nano porous silicon (PS) was formed on -type monocrystalline silicon of 2–5 cm resistivity and (100) orientation by electrochemical anodization method using HF and ethanol as the electrolytes. High density of surface states, arising due to its ...

Tl Cuprate Superconductors Studied by XPS

Energy Technology Data Exchange (ETDEWEB)

Vasquez, R. P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099 (United States); Siegal, M. P. [Sandia National Laboratories, Albuquerque, NM 87185-1421 (United States); Overmyer, D. L. [Sandia National Laboratories, Albuquerque, NM 87185-1421 (United States); Ren, Z. F. [Department of Chemistry, State University of New York, Buffalo, NY 14260-3000 (United States); Lao, J. Y. [Department of Chemistry, State University of New York, Buffalo, NY 14260-3000 (United States); Wang, J. H. [Department of Chemistry, State University of New York, Buffalo, NY 14260-3000 (United States)

1999-07-01

XPS measurements on epitaxial thin films of the Tl cuprate superconductors Tl2Ba2CaCu2O8, Tl2Ba2Ca2Cu3O10, and Tl0.78Bi0.22Ba0.4Sr1.6Ca2Cu3O9-{delta} are presented. These data, together with previous measurements in this lab on Tl2Ba2CuO6-{delta} and TlBa2CaCu2O7-{delta}, comprise a comprehensive data set for comparison of Tl cuprates in which the number of Tl-O and Cu-O layers, and hence the chemical and electronic properties, vary. (c) 2000 American Vacuum Society.

Tl Cuprate Superconductors Studied by XPS

International Nuclear Information System (INIS)

Vasquez, R. P.; Siegal, M. P.; Overmyer, D. L.; Ren, Z. F.; Lao, J. Y.; Wang, J. H.

1999-01-01

XPS measurements on epitaxial thin films of the Tl cuprate superconductors Tl2Ba2CaCu2O8, Tl2Ba2Ca2Cu3O10, and Tl0.78Bi0.22Ba0.4Sr1.6Ca2Cu3O9-δ are presented. These data, together with previous measurements in this lab on Tl2Ba2CuO6-δ and TlBa2CaCu2O7-δ, comprise a comprehensive data set for comparison of Tl cuprates in which the number of Tl-O and Cu-O layers, and hence the chemical and electronic properties, vary. (c) 2000 American Vacuum Society

Práticas não convencionais em saúde por familiares e vínculos afetivos de pacientes críticos Unconventional health practices by family and affective bonds of critic patients

OpenAIRE

Jocelly de Araújo Ferreira; Alana Dionízio Carneiro; Priscilla Tereza Lopes de Souza; Nayda Babel Alves de Lima

2017-01-01

Objetivo: averiguar a aplicabilidade das práticas não convencionais na saúde de visitantes com vínculos afetivos e/ou familiares de pacientes críticos. Métodos: Estudo descritivo, quantitativo, realizado nos ambientes de atendimento ao paciente crítico do Hospital Estadual de Emergência e Trauma, na cidade de João Pessoa – Paraíba. A amostra foi composta por 100 familiares. Os dados foram coletados por meio de entrevista semiestruturada e analisados pelo Software Statistical Package for Socia...

Análise da qualidade superficial e dimensional em peças produzidas por modelagem por deposição de material fundido (FDM

Directory of Open Access Journals (Sweden)

Carlos Henrique Pereira Mello

2010-08-01

Full Text Available A prototipagem rápida vem crescendo cada vez mais como uma opção na busca de redução do tempo e dos riscos no processo de desenvolvimento de produtos. Contudo, as peças produzidas por modelagem por deposição de material fundido (FDM podem sofrer variações na rugosidade e precisão dimensional, dependendo de parâmetros como espessura do filete depositado, sentido da orientação da fabricação da peça, tipo de deposição de camada e geometria do corpo de prova. A literatura é rica em trabalhos dessa natureza a respeito de protótipos rápidos produzidos por outras tecnologias de prototipagem, mas o mesmo não acontece com o FDM. Portanto, a presente pesquisa busca analisar a qualidade superficial e dimensional de protótipos rápidos produzidos com a tecnologia de FDM, por meio de um projeto experimental. De acordo com os dados analisados, foi possível afirmar que algumas variáveis selecionadas como fator principal, ou a interação entre elas, tiveram efeito sobre a resposta rugosidade e nenhum efeito sobre a resposta precisão dimensional. Conclui-se que, na produção de protótipos onde o acabamento superficial for importante, cuidados devem ser tomados na especificação dos parâmetros da máquina, uma vez que a rugosidade da peça final prototipada vai depender fortemente da interação entre os mesmos.

The hidden radiation chemistry in plasma modification and XPS analysis of polymer surfaces

International Nuclear Information System (INIS)

George, G.A.; Le, T.T.; Elms, F.M.; Wood, B.J.

1996-01-01

Full text: The surface modification of polymers using plasma treatments is being widely researched to achieve changes in the surface energetics and consequent wetting and reactivity for a range of applications. These include i) adhesion for polymer bonding and composite material fabrication and ii) biocompatibility of polymers when used as orthopedic implants, catheters and prosthetics. A low pressure rf plasma produces a variety of species from the introduced gas which may react with the surface of a hydrocarbon polymer, such as polyethylene. In the case of 0 2 and H 2 0, these species include oxygen atoms, singlet molecular oxygen and hydroxyl radicals, all of which may oxidise and, depending on their energy, ablate the polymer surface. In order to better understand the reactive species formed both in and downstream from a plasma and the relative contributions of oxidation and ablation, self-assembled monolayers of n-alkane thiols on gold are being used as well characterised substrates for quantitative X-ray photoelectron spectroscopy (XPS). The identification and quantification of oxidised carbon species on plasma treated polymers from broad, asymmetric XPS signals is difficult, so derivatisation is often used to enhance sensitivity and specificity. For example, trifluoroacetic anhydride (TFAA) selectively labels hydroxyl functionality. The surface analysis of a modified polymer surface may be confounded by high energy radiation chemistry which may occur during XPS analysis. Examples include scission of carbon-halogen bonds (as in TFM adducts), decarboxylation and main-chain polyene formation. The extent of free-radical chemistry occurring in polyethylene while undergoing XPS analysis may be seen by both ESR and FT-IR analysis

Quantitative Surface Analysis by Xps (X-Ray Photoelectron Spectroscopy: Application to Hydrotreating Catalysts

Directory of Open Access Journals (Sweden)

Beccat P.

1999-07-01

Full Text Available XPS is an ideal technique to provide the chemical composition of the extreme surface of solid materials, vastly applied to the study of catalysts. In this article, we will show that a quantitative approach, based upon fundamental expression of the XPS signal, has enabled us to obtain a consistent set of response factors for the elements of the periodic table. In-depth spadework has been necessary to know precisely the transmission function of the spectrometer used at IFP. The set of response factors obtained enables to perform, on a routine basis, a quantitative analysis with approximately 20% relative accuracy, which is quite acceptable for an analysis of such a nature. While using this quantitative approach, we have developed an analytical method specific to hydrotreating catalysts that allows obtaining the sulphiding degree of molybdenum quite reliably and reproducibly. The usage of this method is illustrated by two examples for which XPS spectroscopy has provided with information sufficiently accurate and quantitative to help understand the reactivity differences between certain MoS2/Al2O3 or NiMoS/Al2O3-type hydrotreating catalysts.

Partos domiciliares planejados assistidos por enfermeiras obstétricas: transferências maternas e neonatais

Directory of Open Access Journals (Sweden)

Joyce Green Koettker

Full Text Available O presente trabalho trata-se de estudo exploratório-descritivo que teve como objetivo descrever a taxa e as causas de transferência intraparto para o hospital de mulheres assistidas no domicílio por enfermeiras obstétricas e os desfechos desses nascimentos. A amostra foi composta por onze mulheres e seus recém-nascidos, de janeiro de 2005 a dezembro de 2009. Os dados foram coleta-dos em prontuários e cadernetas de saúde e analisados por estatística descritiva. A taxa de transferência foi de 11%, a maioria de nulíparas (63,6%, e todas foram transferidas durante o primeiro período clínico do parto. Os motivos mais frequentes de transferência foram parada de dilatação cervical e progressão da apresentação fetal, e desproporção cefalopélvica. Os escores de Apgar no 1º e 5º minutos foram >7 em 81,8% dos casos e não houve internação em unidade de terapia intensiva neonatal. Neste estudo constatou-se que o parto domiciliar planejado assistido por enfermeiras obstétricas, com protocolo assistencial, apresentou bons resultados maternos e neonatais, mesmo quando a transferência para o hospital foi necessária.

Al2O3 e-Beam Evaporated onto Silicon (100)/SiO2, by XPS

Energy Technology Data Exchange (ETDEWEB)

Madaan, Nitesh; Kanyal, Supriya S.; Jensen, David S.; Vail, Michael A.; Dadson, Andrew; Engelhard, Mark H.; Samha, Hussein; Linford, Matthew R.

2013-09-25

We report the XPS characterization of a thin film of Al2O3 (35 nm) deposited via e-beam evaporation onto silicon (100). The film was characterized with monochromatic Al Ka radiation. An XPS survey scan, an Al 2p narrow scan, and the valence band spectrum were collected. The Al2O3 thin film is used as a diffusion barrier layer for templated carbon nanotube (CNT) growth in the preparation of microfabricated thin layer chromatography plates.

X-ray photoemission spectroscopy (XPS) study of uranium, neptunium and plutonium oxides in silicate-based glasses

International Nuclear Information System (INIS)

Lam, D.J.; Veal, B.W.; Paulikas, A.P.

1982-11-01

Using XPS as the principal investigative tool, we are in the process of examining the bonding properties of selected metal oxides added to silicate glass. In this paper, we present results of XPS studies of uranium, neptunium, and plutonium in binary and multicomponent silicate-based glasses. Models are proposed to account for the very diverse bonding properties of 6+ and 4+ actinide ions in the glasses

XPS characterization of surface and interfacial structure of sputtered TiNi films on Si substrate

International Nuclear Information System (INIS)

Fu Yongqing; Du Hejun; Zhang, Sam; Huang Weimin

2005-01-01

TiNi films were prepared by co-sputtering TiNi and Ti targets. X-ray photoelectron spectroscopy (XPS) was employed to study surface chemistry of the films and interfacial structure of Si/TiNi system. Exposure of the TiNi film to the ambient atmosphere (23 deg. C and 80% relatively humidity) facilitated quick adsorption of oxygen and carbon on the surface. With time, carbon and oxygen content increased drastically at the surface, while oxygen diffused further into the layer. After a year, carbon content at the surface became as high as 65.57% and Ni dropped below the detection limit of XPS. Depth profiling revealed that significant inter-diffusion occurred between TiNi film and Si substrate with a layer of 90-100 nm. The detailed bond changes of different elements with depth were obtained using XPS and the formation of titanium silicides at the interface were identified

XPS and electrochemical studies of the dissolution and passivation of molybdenum-implanted austenitic stainless steels

International Nuclear Information System (INIS)

De Vito, E.; Marcus, P.

1993-01-01

X-ray Photoelectron Spectroscopy (XPS) was used to investigate the chemical composition and the chemical states of the passive film formed on austenitic stainless steels (Fe-19Cr-10Ni (at.%)) which have been implanted with molybdenum (Mo + , 100 keV, 2.5 x 10 16 at./cm 2 ). Prior to passivation the implanted alloy was characterized by RBS (Rutherford Backscattering Spectroscopy) and XPS. Alloys with well-defined surface concentrations of molybdenum were prepared by ion sputtering the implanted alloy in the preparation chamber of the spectrometer, to a fixed point in the implantation profile. The samples were then transferred without air exposure to a glove box with inert gas in which the electrochemical measurements were performed. After passivation, return transfer of the passivated samples was done with the same transfer device to avoid exposure to air. In 0.5 M H 2 SO 4 , the anodic dissolution current density decreases with increasing Mo content on the alloy surface. Surface analysis by XPS showed that the surface is enriched with molybdenum in the Mo 4+ chemical state. The current density in the passive state is similar for both the non-implanted and the implanted alloys. Surface analysis by XPS showed that the passive film has a bilayer structure (inner oxide and outer hydroxide) and that the hydroxide layer present on the surface of the passive film is markedly enriched with molybdenum in the Mo 6+ chemical state. The XPS measurements indicate that the presence of molybdenum favors the formation of chromium hydroxide at the expense of chromium oxide. A significant enrichment of the alloyed (Cr, Ni) and implanted (Mo) elements was also observed in the metallic phase under the passive film. The possible mechanisms of the effect of molybdenum on the corrosion resistance of stainless steels are discussed in light of the obtained surface analytical results

Diamond/carbon nanotube composites: Raman, FTIR and XPS spectroscopic studies

Czech Academy of Sciences Publication Activity Database

Varga, Marián; Ižák, Tibor; Vretenár, V.; Kozak, Halyna; Holovský, Jakub; Artemenko, Anna; Hulman, M.; Skákalová, V.; Lee, D. S.; Kromka, Alexander

2016-01-01

Roč. 111, Jan (2016), s. 54-61 ISSN 0008-6223 R&D Projects: GA ČR GC15-22102J; GA MŠk(CZ) 7AMB14SK037 Institutional support: RVO:68378271 Keywords : diamond * carbon nanotubes * spectroscopy * Raman * FTIR * XPS Subject RIV: JI - Composite Materials Impact factor: 6.337, year: 2016

Structural and XPS studies of PSi/TiO2 nanocomposites prepared by ALD and Ag-assisted chemical etching

International Nuclear Information System (INIS)

Iatsunskyi, Igor; Kempiński, Mateusz; Nowaczyk, Grzegorz; Jancelewicz, Mariusz; Pavlenko, Mykola; Załęski, Karol; Jurga, Stefan

2015-01-01

Highlights: • Porous silicon/TiO 2 nanocomposites have been investigated. • Morphology and chemical composition of PSi/TiO 2 nanocomposites were established. • Valence-band XPS maximums for PSi/TiO 2 nanocomposites were found and analyzed. - Abstract: PSi/TiO 2 nanocomposites fabricated by atomic layer deposition (ALD) and metal-assisted chemical etching (MACE) were investigated. The morphology and phase structure of PSi/TiO 2 nanocomposites were studied by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM) with an energy dispersive X-ray spectroscopy (EDX) and Raman spectroscopy. The mean size of TiO 2 nanocrystals was determined by TEM and Raman spectroscopy. X-ray photoelectron spectroscopy (XPS) was used to analyze the chemical elemental composition by observing the behavior of the Ti 2p, O 1s and Si 2p lines. TEM, Raman spectroscopy and XPS binding energy analysis confirmed the formation of TiO 2 anatase phase inside the PSi matrix. The XPS valence band analysis was performed in order to investigate the modification of PSi/TiO 2 nanocomposites electronic structure. Surface defects states of Ti 3+ at PSi/TiO 2 nanocomposites were identified by analyzing of XPS valence band spectra

Expressão da emoção por meio do desenho de uma criança hospitalizada

Directory of Open Access Journals (Sweden)

Souza Simone Vieira de

2003-01-01

Full Text Available O que desejamos com este trabalho é relatar a experiência de um estudo de caso de uma criança em idade pré-escolar hospitalizada. O foco do estudo é a expressão da emoção por meio de desenhos realizados pela criança em sessões de psicoterapia. Considera-se o desenho como uma atividade expressiva. Os desenhos acompanhados da fala são analisados à luz da teoria histórico-cultural. Os resultados evidenciaram ser o desenho um dos meios utilizados pela criança para expressar sua vivênciaemocional.

Synchrotron radiation as a source for quantitative XPS: advantages and consequences

International Nuclear Information System (INIS)

Rosseel, T.M.; Carlson, T.A.; Negri, R.E.; Beall, C.E.; Taylor, J.W.

1986-01-01

Synchrotron radiation (SR) has a variety of properties which make it an attractive source for quantitative x-ray photoelectron spectroscopy (XPS). Among the most significant are high intensity and tunability. In addition, the intensity of the dispersed radiation is comparable to laboratory line sources. Synchrotron radiation is also a clean source, i.e., it will not contaminate the sample, because it operates under ultra-high vacuum conditions. We have used these properties to demonstrate the advantages of SR as a source for quantitative XPS. We have also found several consequences associated with this source which can either limit its use or provide unique opportunities for analysis and research. Using the tunability of SR, we have measured the energy dependence of the 3p photoionization cross sections of Ti, Cr, and Mn from 50 to 150 eV above threshold at the University of Wisconsin's Tantalus electron-storage ring

Valence band structure of binary chalcogenide vitreous semiconductors by high-resolution XPS

International Nuclear Information System (INIS)

Kozyukhin, S.; Golovchak, R.; Kovalskiy, A.; Shpotyuk, O.; Jain, H.

2011-01-01

High-resolution X-ray photoelectron spectroscopy (XPS) is used to study regularities in the formation of valence band electronic structure in binary As x Se 100−x , As x S 100−x , Ge x Se 100−x and Ge x S 100−x chalcogenide vitreous semiconductors. It is shown that the highest occupied energetic states in the valence band of these materials are formed by lone pair electrons of chalcogen atoms, which play dominant role in the formation of valence band electronic structure of chalcogen-rich glasses. A well-expressed contribution from chalcogen bonding p electrons and more deep s orbitals are also recorded in the experimental valence band XPS spectra. Compositional dependences of the observed bands are qualitatively analyzed from structural and compositional points of view.

Valence band structure of binary chalcogenide vitreous semiconductors by high-resolution XPS

Energy Technology Data Exchange (ETDEWEB)

Kozyukhin, S., E-mail: sergkoz@igic.ras.ru [Russian Academy of Science, Institute of General and Inorganic Chemistry (Russian Federation); Golovchak, R. [Lviv Scientific Research Institute of Materials of SRC ' Carat' (Ukraine); Kovalskiy, A. [Lehigh University, Department of Materials Science and Engineering (United States); Shpotyuk, O. [Lviv Scientific Research Institute of Materials of SRC ' Carat' (Ukraine); Jain, H. [Lehigh University, Department of Materials Science and Engineering (United States)

2011-04-15

High-resolution X-ray photoelectron spectroscopy (XPS) is used to study regularities in the formation of valence band electronic structure in binary As{sub x}Se{sub 100-x}, As{sub x}S{sub 100-x}, Ge{sub x}Se{sub 100-x} and Ge{sub x}S{sub 100-x} chalcogenide vitreous semiconductors. It is shown that the highest occupied energetic states in the valence band of these materials are formed by lone pair electrons of chalcogen atoms, which play dominant role in the formation of valence band electronic structure of chalcogen-rich glasses. A well-expressed contribution from chalcogen bonding p electrons and more deep s orbitals are also recorded in the experimental valence band XPS spectra. Compositional dependences of the observed bands are qualitatively analyzed from structural and compositional points of view.

Limpeza clonal de mudas de videira infectadas por Xanthomonas campestris pv. viticola

Directory of Open Access Journals (Sweden)

Adriano Márcio Freire Silva

2013-03-01

Full Text Available O cancro bacteriano da videira é causado por Xanthomonas campestris pv. viticola (Xcv. Visando à limpeza clonal de mudas de 'Red Globe', foram estudados: tamanho ideal de ápices e gemas axilares para cultivo em meio de Galzy modificado (MGM; efeito da termoterapia (38ºC/30 dias; e ação de antibióticos na eliminação de Xcv em videiras infectadas. Os percentuais de contaminação por Xcv e de regeneração foram analisados, e as plantas obtidas foram indexadas em meio ágar nutritivo-dextrose-extrato de levedura-ampicilina (NYDAM, seguindo-se teste de patogenicidade. O cultivo de explantes com 3 mm possibilitou a obtenção de plantas livres da bactéria, com regeneração 14,3 vezes maior que explantes com 1 mm. A termoterapia de mudas infectadas, associada ao cultivo in vitro, não eliminou o patógeno. O cultivo de explantes com 10 mm, durante 40 dias em MGM + cefotaxima (300 mg L-1, proporcionou limpeza clonal das mudas. A indexação de plantas de videira regeneradas in vitro, quanto à infecção por Xcv utilizando NYDAM, seguida de teste de patogenicidade, é uma alternativa econômica e eficiente para produção de mudas de alta qualidade fitossanitária.

Vergamento da madeira de Eucalyptus grandis plasticizada por vaporização e cozimento

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Matheus Lemos Peres

Full Text Available O vergamento de madeira foi utilizado ao longo dos séculos para a produção de objetos grandes, como estruturas de embarcações ou pequenos utensílios. Mesmo com constantes estudos de vergamento, há carência de melhorias de processo e inclusão de madeiras de baixo valor comercial. Assim, o presente trabalho analisou a madeira vergada de Eucalyptus grandis tratada por diferentes tempos de exposição à vaporização e ao cozimento. Foram analisados o número de tipos de defeitos por peça vergada (Nºdef, a variação no teor de umidade perante os tratamentos (∆Tu, a pressão de extremidade (Pe e a perda de forma circular (Pf. Verificou-se que as variáveis diferem significativamente entre os tipos de tratamento de vaporização e cozimento, exceto para o Nºdef. Os tempos de tratamento não apresentaram efeito significativo. Concluiu-se que a espécie é aceitável para vergamentos em raios inferiores ao utilizado no presente estudo. Adicionalmente, a vaporização mostrou ser o melhor tratamento, por apresentar melhores parâmetros de qualificação.

Quantitative depth profiling of K-doped fullerene films using XPS and SIMS

Czech Academy of Sciences Publication Activity Database

Oswald, S.; Janda, Pavel; Dunsch, L.

2003-01-01

Roč. 141, 1-2 (2003), s. 79-85 E-ISSN 1436-5073 Institutional research plan: CEZ:AV0Z4040901 Keywords : XPS * SIMS * depth profiling * fullerenes * doping Subject RIV: CG - Electrochemistry Impact factor: 0.784, year: 2003

XPS and SEM studies of chromium oxide films chemically formed on stainless steel 316 L

International Nuclear Information System (INIS)

Stefanov, P.; Marinova, T.

2000-01-01

The structure and composition of chromium oxide films formed on stainless steel by immersion in a chromium electrolyte have been studied by SEM and XPS. Cr 2 O 3 crystallites in the range 30-150 nm are fully developed and cover the whole surface. The chemical composition in the depth and the thickness of the oxide layer have been determined by XPS sputter profiles. The oxide film can be described within the framework of a double layer consisting of a thin outer hydrated layer and an inner layer of Cr 2 O 3 . (orig.)

Pd adsorption on Si(1 1 3) surface: STM and XPS study

International Nuclear Information System (INIS)

Hara, Shinsuke; Yoshimura, Masamichi; Ueda, Kazuyuki

2008-01-01

Pd-induced surface structures on Si(1 1 3) have been studied by scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). In the initial process of the Pd adsorption below 0.10 ML, Pd silicide (Pd 2 Si) clusters are observed to form randomly on the surface. By increasing the Pd coverage to 0.10 ML, the clusters cover the entire surface, and an amorphous layer is formed. After annealing the Si(1 1 3)-Pd surface at 600 deg. C, various types of islands and chain protrusions appears. The agglomeration, coalescence and crystallization of these islands are observed by using high temperature (HT-) STM. It is also found by XPS that the islands correspond to Pd 2 Si structure. On the basis of these results, evolution of Pd-induced structures at high temperatures is in detail discussed

Visualization of Gas Distribution in a Model AP-XPS Reactor by PLIF: CO Oxidation over a Pd(100 Catalyst

Directory of Open Access Journals (Sweden)

Jianfeng Zhou

2017-01-01

Full Text Available In situ knowledge of the gas phase around a catalyst is essential to make an accurate correlation between the catalytic activity and surface structure in operando studies. Although ambient pressure X-ray photoelectron spectroscopy (AP-XPS can provide information on the gas phase as well as the surface structure of a working catalyst, the gas phase detected has not been spatially resolved to date, thus possibly making it ambiguous to interpret the AP-XPS spectra. In this work, planar laser-induced fluorescence (PLIF is used to visualize the CO2 distribution in a model AP-XPS reactor, during CO oxidation over a Pd(100 catalyst. The results show that the gas composition in the vicinity of the sample measured by PLIF is significantly different from that measured by a conventional mass spectrometer connected to a nozzle positioned just above the sample. In addition, the gas distribution above the catalytic sample has a strong dependence on the gas flow and total chamber pressure. The technique presented has the potential to increase our knowledge of the gas phase in AP-XPS, as well as to optimize the design and operating conditions of in situ AP-XPS reactors for catalysis studies.

Formation of titanium nitride layers on titanium metal: Results of XPS and AES investigations

International Nuclear Information System (INIS)

Moers, H.; Pfennig, G.; Klewe-Nebenius, H.; Penzhorn, R.D.; Sirch, M.; Willin, E.

1988-09-01

The reaction of titanium metal with gaseous nitrogen and ammonia at temperatures of 890 0 C leads to the formation of nitridic overlayers on the metallic substrate. The thicknesses of the overlayers increase with increasing reaction time. Under comparable conditions ammonia reacts much slower than nitrogen. XPS and AES depth profile analyses show continuous changes of the in-depth compositions of the overlayers. This can be interpreted in terms of a very irregular thickness of the overlayers, an assumption which is substantiated by local AES analyses and by the observation of a pronounced crystalline structure of the substrate after annealing pretreatment, which can give rise to locally different reaction rates. The depth profile is also influenced by the broad ranges of stability of the titanium nitride phases formed during the reaction. The quantitative analysis of the titanium/nitrogen overlayers by AES is difficult because of the overlap of titanium and nitrogen Auger peaks. In quantitative XPS analysis problems arise due to difficulties in defining Ti 2p peak areas. This work presents practical procedures for the quantitative evaluation by XPS and AES of nitridic overlayers with sufficient accuracy. (orig.) [de

Research on the surface chemical behavior of uranium metal in hydrogen atmosphere by XPS

International Nuclear Information System (INIS)

Fu Xiaoguo; Wang Xiaolin; Yu Yong; Zhao Zhengping

2001-01-01

The surface chemical behavior clean uranium metal in hydrogen atmosphere at 100 and 200 degree C is studied by X-ray photoelectron spectroscopy (XPS), respectively. It leads to hydriding reaction when the hydrogen exposure is 12.0 Pa·s, and the U4f 7/2 binding energy of UH 3 is found to be 378.7 eV. The higher temperature (200 degree C) is beneficial to UH 3 formation at the same hydrogen exposures. XPS elemental depth profiles indicate that the distribution of uranium surface layer is UO 2 , UH 3 and U after exposure to 174.2 Pa·s hydrogen

Detergency of stainless steel surface soiled with human brain homogenate: an XPS study

International Nuclear Information System (INIS)

Richard, M.; Le Mogne, Th.; Perret-Liaudet, A.; Rauwel, G.; Criquelion, J.; De Barros, M.I.; Cetre, J.C.; Martin, J.M.

2005-01-01

In the detergency field of re-usable medical devices, a special attention is focused on the non conventional transmissible agent called prions which is a proteinaceous infectious agent. Few cleaning procedures are effective against prions and few techniques are available to study cleaning effectiveness with respect to proteins in general. In our study, X-ray photoelectron spectroscopy (XPS) has been used to evaluate the effectiveness of detergent formulations to remove proteins from stainless steel surface soiled with a brain homogenate (BH) from human origin. Our results showed that XPS is a reliable surface analysis technique to study chemical species remaining on surface and substrate properties after cleaning procedures. A semi-quantitative evaluation of the detergency effectiveness could also be performed

Detergency of stainless steel surface soiled with human brain homogenate: an XPS study

Energy Technology Data Exchange (ETDEWEB)

Richard, M. [Ecole Centrale de Lyon, UMR 5513 LTDS, 69 134 Ecully (France) and Laboratoires ANIOS, 59 260 Lille-Hellemmes (France)]. E-mail: marlene.richard@ec-lyon.fr; Le Mogne, Th. [Ecole Centrale de Lyon, UMR 5513 LTDS, 69 134 Ecully (France); Perret-Liaudet, A. [Hopital Neurologique de Lyon et INSERM U512, 69 394 Lyon (France); Rauwel, G. [Laboratoires ANIOS, 59 260 Lille-Hellemmes (France); Criquelion, J. [Laboratoires ANIOS, 59 260 Lille-Hellemmes (France); De Barros, M.I. [Ecole Centrale de Lyon, UMR 5513 LTDS, 69 134 Ecully (France); Cetre, J.C. [Unite d' Hygiene et d' Epidemiologie, Hopital de la Croix Rousse, 69 317 Lyon (France); Martin, J.M. [Ecole Centrale de Lyon, UMR 5513 LTDS, 69 134 Ecully (France)

2005-02-15

In the detergency field of re-usable medical devices, a special attention is focused on the non conventional transmissible agent called prions which is a proteinaceous infectious agent. Few cleaning procedures are effective against prions and few techniques are available to study cleaning effectiveness with respect to proteins in general. In our study, X-ray photoelectron spectroscopy (XPS) has been used to evaluate the effectiveness of detergent formulations to remove proteins from stainless steel surface soiled with a brain homogenate (BH) from human origin. Our results showed that XPS is a reliable surface analysis technique to study chemical species remaining on surface and substrate properties after cleaning procedures. A semi-quantitative evaluation of the detergency effectiveness could also be performed.

Soft X-ray-induced decomposition of amino acids: An XPS, mass spectrometry, and NEXAFS study

International Nuclear Information System (INIS)

Zubavichus, Yan; Fuchs, Oliver; Weinhardt, Lothar; Heske, Clemens; Umbach, Eberhard; Denlinger, Jonathan D.; Grunze, Michael

2003-01-01

Decomposition of five amino acids, alanine, serine, cysteine, aspartic acid, and asparagine, under irradiation with soft X-rays (magnesium Ka X-ray source) in ultra-high vacuum was studied by means of X-ray photoelectron spectrometry (XPS) and mass spectrometry. A comparative analysis of changes in XPS line shapes, stoichiometry and residual gas composition indicates that the molecules decompose by several pathways. Dehydration, decarboxylation, decarbonylation,deamination and desulfurization of pristine molecules accompanied by desorption of H2, H2O, CO2, CO, NH3and H2S are observed with rates depending on the specific amino acid. NEXAFS spectra of cysteine at the carbon, oxygen and nitrogen K-shell and sulfur L2,3 edges complement the XPS and mass spectrometry data and show that the exposure of the sample to an intense soft X-ray synchrotron beam results in the formation of C-C and C-N double and triple bonds. Qualitatively, the amino acids studied can be arranged in the following ascending order of radiation stability:serine< alanine< aspartic acid< cysteine< asparagine

Silicon (100)/SiO2 by XPS

Energy Technology Data Exchange (ETDEWEB)

Jensen, David S.; Kanyal, Supriya S.; Madaan, Nitesh; Vail, Michael A.; Dadson, Andrew; Engelhard, Mark H.; Linford, Matthew R.

2013-09-25

Silicon (100) wafers are ubiquitous in microfabrication and, accordingly, their surface characteristics are important. Herein, we report the analysis of Si (100) via X-ray photoelectron spectroscopy (XPS) using monochromatic Al K radiation. Survey scans show that the material is primarily silicon and oxygen, and the Si 2p region shows two peaks that correspond to elemental silicon and silicon dioxide. Using these peaks the thickness of the native oxide (SiO2) was estimated using the equation of Strohmeier.1 The oxygen peak is symmetric. The material shows small amounts of carbon, fluorine, and nitrogen contamination. These silicon wafers are used as the base material for subsequent growth of templated carbon nanotubes.

Cryogenic XPS study of fast-frozen sulfide minerals: Flotation-related adsorption of n-butyl xanthate and beyond

Energy Technology Data Exchange (ETDEWEB)

Mikhlin, Yuri, E-mail: yumikh@icct.ru [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk 660036 (Russian Federation); Karacharov, Anton; Tomashevich, Yevgeny [Institute of Chemistry and Chemical Technology of the Siberian Branch of the Russian Academy of sciences, Akademgorodok, 50/24, Krasnoyarsk 660036 (Russian Federation); Shchukarev, Andrey [Department of Chemistry, Umeå University, Umeå SE-901 87 (Sweden)

2016-01-15

Highlights: • Mineral/aqueous solution interfaces were studied with quasi in situ cryo-XPS. • Dibutyl dixanthogen was the major xanthate adsorption product on pyrite. • Dixanthogen and minor cuprous xanthate were uptaken by chalcopyrite. • Xanthate was chemisorbed at PbS. • Ice-repellent character of hydrophobic particles caused charging effects in XPS. - Abstract: Cryogenic XPS of wet particulate samples separated via centrifugation and fast-frozen allows quasi in situ examination of solid surfaces, adsorbates, and reaction products, largely preventing the loss both of volatiles and hydrated species at mineral/water interfaces. Here, the cryo-XPS has been applied to characterize the surfaces and interfacial layers of natural pyrite (FeS{sub 2}), chalcopyrite (CuFeS{sub 2}), and galena (PbS) in solutions of a common flotation collector, potassium n-butyl xanthate (KBX), in conjunction with zeta-potential measurement. It was found, in particular, that dibutyl dixanthogen was the major adsorbate at pyrite in 0.1 mM KBX and 10 mM KBX solutions; dixanthogen and cuprous xanthate in the next stage were formed on chalcopyrite, and predominant chemisorbed butyl xanthate was present at galena, including in 10 mM KBX solution. The results may suggest that the production of dixanthogens at the interface has been underestimated while the quantities of surface metal xanthates could be over evaluated in previous studies. Pronounced differential charging effects were observed in the XPS experiment for the samples moderately hydrophobized by the xanthate treatment; we proposed that the effect was due to electrically isolated mineral particles with hydrophobic and ice-repellent surfaces, which retained, however, some frozen water islets.

XPS analysis of boron doped heterofullerenes

Energy Technology Data Exchange (ETDEWEB)

Schnyder, B; Koetz, R [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Muhr, H J; Nesper, R [ETH Zurich, Zurich (Switzerland)

1997-06-01

Boron heterofullerenes were generated through arc-evaporation of doped graphite rods in a helium atmosphere. According to mass spectrometric analysis only mono-substituted fullerenes like C{sub 59}B, C{sub 69}B and higher homologues together with a large fraction of higher undoped fullerenes were extracted and enriched when pyridine was used as the solvent. XPS analysis of the extracts indicated the presence of two boron species with significantly different binding energies. One peak was assigned to borid acid. The second one corresponds to boron in the fullerene cage, which is mainly C{sub 59}B, according to the mass spectrum. This boron is in a somewhat higher oxidation state than that of ordinary boron-carbon compounds. The reported synthesis and extraction procedure opens a viable route for production of macroscopic amounts of these compounds. (author) 2 figs., 1 tab., 7 refs.

SEM and XPS study of layer-by-layer deposited polypyrrole thin films

Science.gov (United States)

Pigois-Landureau, E.; Nicolau, Y. F.; Delamar, M.

1996-01-01

Layer-by-layer deposition of thin films (a few nm) of polypyrrole was carried out on various substrates such as silver, platinum, electrochemically oxidized aluminum and pretreated glass. SEM micrographs showed that the deposited layers nucleate by an island-type mechanism on hydrated alumina and KOH-pretreated (hydrophilic) glass before forming a continuous film. However, continuous thin films are obtained on chromic acid pretreated (hydrophobic) glass and sputtered Ag or Pt on glass after only 3-4 deposition cycles. The mean deposition rate evaluated by XPS for the first deposition cycles on Ag and Pt is 3 and 4 nm/cycle, respectively, in agreement with previous gravimetric determinations on thicker films, proving the constancy of the deposition rate. The XPS study of the very thin films obtained by a few deposition cycles shows that the first polypyrrole layers are dedoped by hydroxydic (basic) substrate surfaces.

Rondorfite-type structure — XPS and UV–vis study

Energy Technology Data Exchange (ETDEWEB)

Dulski, M., E-mail: mateusz.dulski@smcebi.edu.pl [Institute of Material Science, University of Silesia, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Bilewska, K., E-mail: kbilewska@us.edu.pl [A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); Institute of Non-Ferrous Metals, Sowińskiego 5, 44-100 Gliwice (Poland); Wojtyniak, M., E-mail: marcin.wojtyniak@us.edu.pl [Institute of Material Science, University of Silesia, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); Szade, J., E-mail: jacek.szade@us.edu.pl [A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); Kusz, J., E-mail: joachim.kusz@us.edu.pl [A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Nowak, A., E-mail: ana.maria.nowak@gmail.com [A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); Wrzalik, R., E-mail: roman.wrzalik@us.edu.pl [A.Chelkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzow (Poland); and others

2015-10-15

Highlights: • Structural and spectroscopic characterization of chlorosilicate mineral, rondorfite. • Characterization of main photoemission lines and valence band spectra. • The study of color origin’s using UV–vis spectroscopy. • Analysis of structural changes in context of origin of natural fluorescence. • Discussion of a new application possibilities of analyzed mineral - Abstract: This paper focuses on X-ray diffraction, X-ray photoelectron and UV–vis spectroscopy of two different (green, orange) rondorfite samples. The differences in the sample color originate from various O/Cl ratios. The orange color was found to be related either to the isomorphic substitution of Fe{sup 3+}/Al{sup 3+} for Mg{sup 2+}, the presence of atypical [MgO{sub 4}] tetrahedrons in crystal structure or electronegativity of the sample. The tetrahedron is known to be very prone to accumulation of impurities and substitute atoms. Moreover, the XPS data showed tetrahedrally coordinated Mg{sup 2+} and isomorphic substitution of Al{sup 3+}/Fe{sup 3+} for Mg{sup 2+}, which influences local disordering and the point defects density and distribution. Non-equilibrium chlorine positions inside the crystal cages as well as Ca-Cl bonds have also been found. The XPS measurements as a function of temperature indicate occurrence of a structural transformation at about 770 K which is accompanied by a rotation of silicate tetrahedra within magnesiosilicate pentamer and luminescence disappearance.

An in situ XPS study of L-cysteine co-adsorbed with water on polycrystalline copper and gold

Science.gov (United States)

Jürgensen, Astrid; Raschke, Hannes; Esser, Norbert; Hergenröder, Roland

2018-03-01

The interactions of biomolecules with metal surfaces are important because an adsorbed layer of such molecules introduces complex reactive functionality to the substrate. However, studying these interactions is challenging: they usually take place in an aqueous environment, and the structure of the first few monolayers on the surface is of particular interest, as these layers determine most interfacial properties. Ideally, this requires surface sensitive analysis methods that are operated under ambient conditions, for example ambient pressure x-ray photoelectron spectroscopy (AP-XPS). This paper focuses on an AP-XPS study of the interaction of water vapour and l-Cysteine on polycrystalline copper and gold surfaces. Thin films of l-Cysteine were characterized with XPS in UHV and in a water vapour atmosphere (P ≤ 1 mbar): the structure of the adsorbed l-Cysteine layer depended on substrate material and deposition method, and exposure of the surface to water vapour led to the formation of hydrogen bonds between H2O molecules and the COO- and NH2 groups of adsorbed l-Cysteine zwitterions and neutral molecules, respectively. This study also proved that it is possible to investigate monolayers of biomolecules in a gas atmosphere with AP-XPS using a conventional laboratory Al-Kα x-ray source.

Concepções sobre drogas por adolescentes escolares

Directory of Open Access Journals (Sweden)

Edson Arantes Faria Filho

2015-06-01

Full Text Available RESUMOObjetivo:analisar concepções de adolescentes escolares da educação básica sobre drogas em geral.Método:abordagem qualitativa de grupos focais com 16 adolescentes estudantes. Os dados coletados foram analisados por Análise de Conteúdo, onde emergiram as seguintes categorias “Significado de drogas”; “Convivendo com o uso de drogas”; “Opiniões, crenças e atitudes em relação ao uso de drogas” e “Prevenindo o uso indevido de drogas na adolescência”.Resultados:os adolescentes conhecem algumas drogas associando o uso à marginalidade e à criminalidade. Identifi caram fatores que levam ao consumo abusivo de drogas como fácil acesso, uso familiar e com grupos de amigos, ociosidade, abandono escolar e vulnerabilidade característica da adolescência.Conclusão:os resultados demonstram a necessidade da implementação de trabalhos educativos no contexto em que os adolescentes vivem, seja escolar, social e familiar de modo a apoiar e minimizar as diversas vulnerabilidades dos adolescentes.

Gold/silver core-shell 20 nm nanoparticles extracted from citrate solution examined by XPS

Energy Technology Data Exchange (ETDEWEB)

Engelhard, Mark H.; Smith, Jordan N.; Baer, Donald R.

2016-06-01

Silver nanoparticles of many types are widely used in consumer and medical products. The surface chemistry of particles and the coatings that form during synthesis or use in many types of media can significantly impact the behaviors of particles including dissolution, transformation and biological or environmental impact. Consequently it is useful to be able to extract information about the thickness of surface coatings and other attributes of nanoparticles produced in a variety of ways. It has been demonstrated that X-ray Photoelectron Spectroscopy (XPS) can be reliably used to determine the thickness of organic and other nanoparticles coatings and shells. However, care is required to produce reliable and consistent information. Here we report the XPS spectra from gold/silver core-shell nanoparticles of nominal size 20 nm removed from a citrate saturated solution after one and two washing cycles. The Simulation of Electron Spectra for Surface Analysis (SESSA) program had been used to model peak amplitudes to obtain information on citrate coatings that remain after washing and demonstrate the presence of the gold core. This data is provided so that others can compare use of SESSA or other modeling approaches to quantify the nature of coatings to those already published and to explore the impacts particle non-uniformities on XPS signals from core-shell nanoparticles.

Conversion electron Moessbauer and XPS study on the effect of polishing of a stainless steel sample

International Nuclear Information System (INIS)

Vertes, Cs.; Kuzmann, E.; Lakatos-Varsanyi, M.; Vertes, A.; Vass, G.; Romhanyi, K.

1994-01-01

Conversion electron Moessbauer spectroscopy (CEMS) and XPS has been used for the surface analysis of an 'X10CrNiTi 18/9 (DIN 1.7440)'-type stainless steel in order to determine the supposed structural and/or chemical changes in the surface layer caused by polishing. Both, CEMS and XPS results can be associated with the appearance of Fe nitride in the outer layer of steel samples after polishing, while no sing of nitrogen was detected in the bulk material. (author) 9 refs.; 3 figs.; 1 tab

SEM and XPS study of layer-by-layer deposited polypyrrole thin films

International Nuclear Information System (INIS)

Pigois-Landureau, E.; Nicolau, Y.F.; Delamar, M.

1996-01-01

Layer-by-layer deposition of thin films (a few nm) of polypyrrole was carried out on various substrates such as silver, platinum, electrochemically oxidized aluminum and pretreated glass. SEM micrographs showed that the deposited layers nucleate by an island-type mechanism on hydrated alumina and KOH-pretreated (hydrophilic) glass before forming a continuous film. However, continuous thin films are obtained on chromic acid pretreated (hydrophobic) glass and sputtered Ag or Pt on glass after only 3 endash 4 deposition cycles. The mean deposition rate evaluated by XPS for the first deposition cycles on Ag and Pt is 3 and 4 nm/cycle, respectively, in agreement with previous gravimetric determinations on thicker films, proving the constancy of the deposition rate. The XPS study of the very thin films obtained by a few deposition cycles shows that the first polypyrrole layers are dedoped by hydroxydic (basic) substrate surfaces. copyright 1996 American Institute of Physics

Chemical state analysis of conversion coatings by SR-XPS and TEY-XANES

CERN Document Server

Noro, H; Nagoshi, M

2002-01-01

Chromate coatings on galvanized steel have been studied by Synchrotron Radiation (SR) based techniques that include X-ray Photoelectron Spectroscopy (XPS) and Total-Electron-Yield X-ray Absorption Near Edge Structure (TEY-XANES). Non-destructive depth profiling of the coatings by SR-XPS reveals the enhancement of Cr sup 6 sup + in the outer surface. TEY-XANES spectroscopy based on simple specimen current measurement is demonstrated as an effective technique for analyzing chemical states of conversion coatings on general bulk substrates. The sampling depth of this technique, which exceeds several tens of nanometer, is determined by the penetration length of Auger electrons excited by X-ray and the inelastic mean free path of secondary electrons excited by inelastically scattered Auger electrons. The chemical states of phosphoric acid added chromate coatings are studied using this technique. The phosphoric acid is taken into the chromate coatings as partially changed into zinc and chromium phosphates, and the r...

Speciation of uranium after microbial action by XANES and XPS

International Nuclear Information System (INIS)

Dodge, C.J.; Francis, A.J.; Lu, F.; Halada, G.P.; Kagwade, S.V.; Clayton, C.R.

1993-01-01

The speciation of radionuclides and toxic metals in wastes subjected to microbial action is important in determining the extent of stabilization in a disposal environment. As part of an ongoing study, we investigated the reduction of uranium by a Clostridium sp. using X-ray absorption neat edge spectroscopy (XANES) at the National Synchrotron Light Source (NSLS) and X-ray photoelectron spectroscopy (XPS). XPS analysis of uranyl acetate containing hexavalent uranium exhibited a binding energy of 382.0eV at the U 4f 7/2 peak. The sample incubated in the presence of bacteria was shifted to lower binding energy (380.6eV), confirming the reduction of U 6+ to U 4+ at the bacterial surface. XANES analysis, using an electron yield detector, was performed at the M v absorption edge (3d-->5f). The absorption peak energy of the sample exhibited a shift from 3551.1eV to 3550.1eV which is higher than uranium metal (3549.6eV ) but lower than U 4+ (3550.4eV). This indicates the presence of U 3+ which is probably located beneath the surface within the biomass. Anaerobic bacterial treatment of wastes containing uranyl ion can result in the stabilization of uranium

XPS/STM study of model bimetallic Pd–Au/HOPG catalysts

Energy Technology Data Exchange (ETDEWEB)

Bukhtiyarov, Andrey V., E-mail: avb@catalysis.ru [Boreskov Institute of Catalysis, Lavrentieva Ave. 5, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation); Prosvirin, Igor P., E-mail: prosvirin@catalysis.ru [Boreskov Institute of Catalysis, Lavrentieva Ave. 5, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation); Bukhtiyarov, Valerii I., E-mail: vib@catalysis.ru [Boreskov Institute of Catalysis, Lavrentieva Ave. 5, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation)

2016-03-30

Graphical abstract: - Highlights: • The model Pd–Au/HOPG catalysts preparation has been studied by XPS and STM. • Model “core–shell” type Pd–Au/HOPG catalysts with different Pd/Au ratios were prepared. • Heating of the “core–shell” Pd–Au/HOPG samples up to 400 °C leads to alloy formation. • Contribution of parameters controlling the properties of Pd–Au alloyed particles has been discussed. - Abstract: The preparation of model bimetallic Pd–Au/HOPG catalysts has been investigated using scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) techniques. Initially, model “core–shell” type Pd–Au/HOPG catalysts with similar particle size distribution (5–8 nm), but with different densities of particle locations on the HOPG surface and Pd/Au atomic ratios are prepared. Further, their thermal stability is studied within a temperature range of 50–500 °C at UHV conditions. It has been shown that annealing the model catalysts at a temperature range of 300–400 °C leads to formation of Pd–Au alloyed particles. Enhancement of heating temperature up to 500 °C results in sintering of bimetallic nanoparticles. Contribution of different parameters controlling the properties of Pd–Au alloyed particles has been discussed.

Investigating early stages of biocorrosion with XPS: AISI 304 stainless steel exposed to Burkholderia species

Science.gov (United States)

Johansson, Leena-Sisko; Saastamoinen, Tuomas

1999-04-01

We have investigated the interactions of an exopolymer-producing bacteria, Burkholderia sp. with polished AISI 304 stainless steel substrates using X-ray photoelectron spectroscopy (XPS). Steel coupons were exposed to the pure bacteria culture in a specially designed flowcell for 6 h during which the experiment was monitored in situ with an optical microscope. XPS results verified the formation of biofilm containing extracellular polymer on all the samples exposed to bacteria. Sputter results indicated that some ions needed for metabolic processes were trapped within the biofilm. Changes in the relative Fe concentration and Fe 2p peak shape indicated that also iron had accumulated into the biofilm.

The Psychology of Music, editado por Diana Deutsch, 3ª edição: resenha dos capítulos 10 a 13

Directory of Open Access Journals (Sweden)

Ricieri Carlini Zorzal

2016-03-01

Full Text Available O presente texto traz uma resenha de quatro capítulos da terceira edição do livro The Psychology of Music, editado por Diana Deutsch. Nominalmente, são analisados os seguintes capítulos: 10 Performance musical: movimento e coordenação, de autoria de Caroline Palmer; 11 Desenvolvimento musical, de autoria de Laurel Trainor e Erin Hannon; 12 Música e habilidades cognitivas, de autoria de Glenn Schellenberg e Michael Weiss; e 13 As fundações biológicas da música: insights da amusia congênita, de autoria de Isabelle Peretz.

GESTÃO POR COMPETÊNCIAS UM ESTUDO DOS IMPACTOS GERADOS NA AVALIAÇÃO DE DESEMPENHO E REMUNERAÇÃO

Directory of Open Access Journals (Sweden)

Leila Vaz Silva

2011-03-01

Full Text Available A abordagem relacionada à gestão de pessoas baseada em competências tem sido um tema freqüente no ambiente organizacional. Considerando o cenário de constantes mudanças torna-se um desafio a manutenção da vantagem competitiva, o que justifica o interesse pelo tema. Este estudo teve o objetivo de descrever e identificar como é realizada a avaliação de desempenho em uma empresa do ramo de mineração que adotou a gestão de competências, analisando os reflexos do seu resultado na remuneração. Realizou-se uma pesquisa qualitativa por meio da estratégia do estudo de caso, sendo os dados coletados por meio de entrevistas e analisados adotando-se a análise do conteúdo. Como técnica auxiliar utilizou-se ainda a análise de desenhos, procurando retratar a percepção dos participantes sobre a gestão por competências. Os resultados indicam que a opção pela implantação do sistema de gestão por competências permitiu que os funcionários entendessem de modo mais claro o seu papel organizacional

Structural, photoluminescence and XPS properties of Tm3þ ions in ZnO nanostructures

CSIR Research Space (South Africa)

Kabongo, GL

2017-07-01

Full Text Available of photoluminescence (PL) spectroscopy. Finally, Tm 4d core level was detected in ZnO: 0.5 mol% Tm(sup3+) sample from high resolution X-Ray Photoelectron Spectroscopy (XPS) scan....

XPS characterization of the anodic oxide film formed on uranium metal in sodium hydroxide solution

International Nuclear Information System (INIS)

Fu Xiaoguo; Wang Xiaolin; Guo Huanjun; Wang Qingfu; Zhao Zhengping; Zhong Yongqiang

2002-01-01

X-ray photoelectron spectroscopy (XPS) is used to examine the anodic oxide film formed on uranium metal in 0.8 mol/L NaOH solution. The U4f 7/2 fitting spectra suggests that the anodic oxide film is composed of uranium trioxide and a small amount of UO 2+x . Under UHV condition, the U4f peak shifts to the lower binding energy, while a gradual increase in the intensity of U5f peak and the broad of U4f peak are also observed. All of these changes are due to reduction of uranium trioxide in the anodic oxide film. XPS quantitative analysis confirms the occurrence of reduction reaction

Effects of Mn Ion Implantation on XPS Spectroscopy of GaN Thin Films

Science.gov (United States)

Majid, Abdul; Ahmad, Naeem; Rizwan, Muhammad; Khan, Salah Ud-Din; Ali, Fekri Abdulraqeb Ahmed; Zhu, Jianjun

2018-02-01

Gallium nitride (GaN) thin film was deposited onto a sapphire substrate and then implanted with 250 keV Mn ions at two different doses of 2 × 1016 ions/cm2 and 5 × 1016 ions/cm2. The as-grown and post-implantation-thermally-annealed samples were studied in detail using x-ray photoelectron spectroscopy (XPS). The XPS peaks of Ga 3 d, Ga 2 p, N 1 s, Mn 2 p and C 1 s were recorded in addition to a full survey of the samples. The doublet peaks of Ga 2 p for pure GaN were observed blue-shifted when compared with elemental Ga, and appeared further shifted to higher energies for the implanted samples. These observations point to changes in the bonds and the chemical environment of the host as a result of ion implantation. The results revealed broadening of the N 1 s peak after implantation, which is interpreted in terms of the presence of N-Mn bonds in addition to N-Ga bonds. The XPS spectra of Mn 2 p recorded for ion-implanted samples indicated splitting of Mn 2 p 1/2 and Mn 2 p 3/2 peaks higher than that for metallic Mn, which helps rule out the possibility of clustering and points to substitutional doping of Mn. These observations provide a framework that sheds light on the local environment of the material for understanding the mechanism of magnetic exchange interactions in Mn:GaN based diluted magnetic semiconductors.

GD-OES and XPS coupling: A new way for the chemical profiling of photovoltaic absorbers

Energy Technology Data Exchange (ETDEWEB)

Mercier, Dimitri, E-mail: dimitri.mercier@uvsq.fr [Institut Lavoisier de Versailles, 45 av. des Etats-Unis, 78035 Versailles Cedex (France); Bouttemy, Muriel; Vigneron, Jackie [Institut Lavoisier de Versailles, 45 av. des Etats-Unis, 78035 Versailles Cedex (France); Chapon, Patrick [HORIBA Jobin Yvon SAS, F-91165 Longjumeau (France); Etcheberry, Arnaud [Institut Lavoisier de Versailles, 45 av. des Etats-Unis, 78035 Versailles Cedex (France)

2015-08-30

Highlights: • The coupling between GD-OES and XPS analysis is a promising way for fine characterization of thin layers. • Crater surface modifications obtained after GD-OES sputtering depend to the plasma gas. • Inversion of the gas flow improves the surface of the crater. • The modified layer is totally eliminated a few seconds after restarting GD-OES sputtering. - Abstract: In this paper, we examine the complementarity of Glow Discharge Optical Emission Spectroscopy (GD-OES) and X Ray Photoelectron Spectroscopy (XPS) for the realization of fine chemical depth profiling of photovoltaic absorbers using Cu(In,Ga)Se{sub 2} (CIGS) materials. The possibility to use sequentially these two techniques is discussed in this paper. We have evaluated the chemical modifications of the crater after GD-OES analyses which depend on the manner of finishing the plasma etching sequence; and we propose different ways to limit or eliminate this effect. For the moment, an intermediate step (wet chemical etching or weak sputtering) is required to obtain a CIGS phase in the crater. Finally, we have demonstrated the possibility to restart the GD-OES analyses of the materials after XPS quantification or GD-OES breaking without modifying the profile shape.

Expressão de colageno IV e laminina urinarios no diabetes mellitus induzidos por drogas (aloxana e estreptozotocina) e avaliação morfo-funcional renal

OpenAIRE

Elizabeth João Pavin

1995-01-01

Resumo: A excreção urinária de componentes da membrana basal, especificamente colágeno IV e laminina, foi determinada através de "immunoblotting", e estudada em ratos Wistar machos, diabéticos-induzido por drogas (aloxana e estreptozotocina) EV, e comparada a controles, em função do tempo de doença. Estudamos, também, as funções renais: glomerular e tubular, avaliando, respectivamente, clearance de creatinina e de lítio. Além disso, aspectos morfológicos renais foram analisados utilizando-se ...

XPS study of the passive layers formed on lead in aqueous nitrate solutions

International Nuclear Information System (INIS)

Uchida, Miho; Okuwaki, Akitsugu

1997-01-01

The analysis of the lead surface immersed in aqueous nitrate solutions by X-ray photoelectron spectroscopy (XPS) shows the formation of passive oxide layer containing nitrogen compound. The oxide layer formed on the lead surface in aqueous ammonium nitrate solution was hydrolyzed and cracked. (author)

Comparing XPS on bare and capped ZrN films grown by plasma enhanced ALD: Effect of ambient oxidation

Science.gov (United States)

Muneshwar, Triratna; Cadien, Ken

2018-03-01

In this article we compare x-ray photoelectron spectroscopy (XPS) measurements on bare- and capped- zirconium nitride (ZrN) films to investigate the effect of ambient sample oxidation on the detected bound O in the form of oxide ZrO2 and/or oxynitride ZrOxNy. ZrN films in both bare- and Al2O3/AlN capped- XPS samples were grown by plasma-enhanced atomic layer deposition (PEALD) technique using tetrakis dimethylamino zirconium (TDMAZr) precursor, forming gas (5% H2, rest N2) inductively coupled plasma (ICP), and as received research grade process gases under identical process conditions. Capped samples were prepared by depositing 1 nm thick PEALD AlN on ZrN, followed by additional deposition of 1 nm thick ALD Al2O3, without venting of ALD reactor. On bare ZrN sample at room temperature, spectroscopic ellipsometry (SE) measurements with increasing ambient exposure times (texp) showed a self-limiting surface oxidation with the oxide thickness (dox) approaching 3.7 ± 0.02 nm for texp > 120 min. In XPS data measured prior to sample sputtering (tsput = 0), ZrO2 and ZrOxNy were detected in bare- samples, whereas only ZrN and Al2O3/AlN from capping layer were detected in capped- samples. For bare-ZrN samples, appearance of ZrO2 and ZrOxNy up to sputter depth (dsput) of 15 nm in depth-profile XPS data is in contradiction with measured dox = 3.7 nm, but explained from sputtering induced atomic inter-diffusion within analyzed sample. Appearance of artifacts in the XPS spectra from moderately sputtered (dsput = 0.2 nm and 0.4 nm) capped-ZrN sample, provides an evidence to ion-bombardment induced modifications within analyzed sample.

Heat capacity measurements and XPS studies on uranium-lanthanum mixed oxides

International Nuclear Information System (INIS)

Venkata Krishnan, R.; Mittal, V.K.; Babu, R.; Senapati, Abhiram; Bera, Santanu; Nagarajan, K.

2011-01-01

Research highlights: → Heat capacity measurements were carried out on (U 1-y La y )O 2±x (y = 0.2, 0.4, 0.6, and 0.8) using differential scanning calorimeter (DSC) in the temperature range 298-800 K. → Enthalpy increment measurements were carried out on the above solid solution using high temperature drop calorimetry in the temperature range 800-1800 K. → Chemical states of U and La in the solid solutions of mixed oxides were determined using X-ray photoelectron spectroscopy (XPS). → The anomalous increase in the heat capacity is attributed to certain thermal excitation process namely Frenkel pair defect of oxygen. → From the XPS investigation, it is observed that the O/M ratio at the surface is higher than that to the bulk. → In uranium rich mixed oxide samples, the surface O/M is greater than 2 whereas that in La rich mixed oxides, it is less than 2, though the bulk O/M in all the samples are less than 2. - Abstract: Heat capacity measurements were carried out on (U 1-y La y )O 2±x (y = 0.2, 0.4, 0.6, and 0.8) using differential scanning calorimeter (DSC) in the temperature range 298-800 K. Enthalpy increment measurements were carried out on the above solid solutions using high temperature drop calorimetry in the temperature range 800-1800 K. Chemical states of U and La in the solid solutions of mixed oxides were determined using X-ray photoelectron spectroscopy (XPS). Oxygen to metal ratios of (U 1-y La y )O 2±x were estimated from the ratios of different chemical states of U present in the sample. Anomalous increase in the heat capacity is observed for (U 1-y La y )O 2±x (y = 0.4, 0.6 and 0.8) with onset temperatures in the range of 1000-1200 K. The anomalous increase in the heat capacity is attributed to certain thermal excitation process, namely, Frenkel pair defect of oxygen. The heat capacity value of (U 1-y La y )O 2±x (y = 0.2, 0.4, 0.6, and 0.8) at 298 K are 65.3, 64.1, 57.7, 51.9 J K -1 mol -1 , respectively. From the XPS investigations

Positive XPS binding energy shift of supported Cu{sub N}-clusters governed by initial state effects

Energy Technology Data Exchange (ETDEWEB)

Peters, S.; Peredkov, S. [Technische Universität Berlin, IOAP, Strasse des 17. Juni 135, 10623 Berlin (Germany); Al-Hada, M. [Department of Physics, College of Education and Linguistics, University of Amran (Yemen); Neeb, M., E-mail: matthias.neeb@helmholtz-berlin.de [Helmholtz-Zentrum Berlin, Wilhelm-Conrad-Röntgen-Campus Adlershof, Elektronenspeicherring BESSY II, Albert-Einstein-Straße 15, 12489 Berlin (Germany); Eberhardt, W. [Technische Universität Berlin, IOAP, Strasse des 17. Juni 135, 10623 Berlin (Germany); DESY, Center for Free Electron Laser Science (CFEL), Notkestr. 85, 22607 Hamburg (Germany)

2014-01-01

Highlights: • Size dependent initial and final state effects of mass-selected deposited clusters. • Initial state effect dominates positive XPS shift in supported Cu-clusters. • Size dependent Coulomb correlation shift in the Auger final state of Cu cluster. • Size-dependent Auger parameter analysis. • Positive XPS shift differs from negative surface core level shift in crystalline copper. - Abstract: An initial state effect is established as origin for the positive 2p core electron binding energy shift found for Cu{sub N}-clusters supported by a thin silica layer of a p-doped Si(1 0 0) wafer. Using the concept of the Auger parameter and taking into account the usually neglected Coulomb correlation shift in the Auger final state (M{sub 4,5}M{sub 4,5}) it is shown that the initial state shift is comparable to the measured XPS shift while the final state relaxation shift contributes only marginally to the binding energy shift. The cluster results differ from the negative surface core-level shift of crystalline copper which has been explained in terms of a final state relaxation effect.

XANES and XPS studies of the reduction of ammonium paramolybdate

International Nuclear Information System (INIS)

Halada, G.P.; Clayton, C.R.

1991-01-01

in situ glancing-angle x-ray reflectivity experiments were performed on electrochemical reduction products formed in a dilute paramolybdate solution on a platinum electrode. These data were compared with x-ray photoelectron spectra which showed formation of simple molybdate, pentavalent and tetravalent species at increasingly negative potentials. X-ray absorption data demonstrated changes in edge position, pre-edge structure and edge height corresponding to reduction and subsequent growth of the reduction product film at a number of the potentials examined with XPS

A comparative study on defect estimation using XPS and Raman spectroscopy in few layer nanographitic structures.

Science.gov (United States)

Ganesan, K; Ghosh, Subrata; Gopala Krishna, Nanda; Ilango, S; Kamruddin, M; Tyagi, A K

2016-08-10

Defects in planar and vertically oriented nanographitic structures (NGSs) synthesized by plasma enhanced chemical vapor deposition (PECVD) have been investigated using Raman and X-ray photoelectron spectroscopy. While Raman spectra reveal the dominance of vacancy and boundary type defects respectively in vertical and planar NGSs, XPS provides additional information on vacancy related defect peaks in the C 1s spectrum, which originate from non-conjugated carbon atoms in the hexagonal lattice. Although an excellent correlation prevails between these two techniques, our results show that estimation of surface defects by XPS is more accurate than Raman analysis. Nuances of these techniques are discussed in the context of assessing defects in nanographitic structures.

Growth of TiC films by Pulsed Laser Evaporation (PLE) and characterization by XPS and AES

International Nuclear Information System (INIS)

Rist, O.; Murray, P.T.

1991-01-01

Thin films of TiC with a thickness of some 100 nm have been grown on Si(100) substrates by Pulsed Laser Evaporation (PLE). Advantages of PLE in comparison with more conventional growth methods e.g. PVD or CVD are reported. The feasibility of growing stoichiometric thin films of TiC by PLE was investigated. These films produced have been analysed in situ by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). XPS results and Auger sputter depht profiles indicate that the films grown between RT and 500degC are stoichiometric TiC. Film/substrate interdiffusion is observed at 600degC substrate temperature and higher. (orig.)

Aposentadoria por invalidez de trabalhadores da área da saúde de um hospital universitário Disability retirement of workers in the health field at a university hospital

Directory of Open Access Journals (Sweden)

Júlia Trevisan Martins

2017-01-01

Full Text Available Objetivo: Identificar as causas da aposentadoria por invalidez de trabalhadores da área da saúde de um hospital universitário. Método: Estudo seccional retrospectivo, realizado em 2014, por meio da análise dos registros dos prontuários de saúde dos trabalhadores da área da saúde do hospital universitário de uma universidade pública paranaense que se aposentaram por invalidez, no período de 2000 a 2013. Os dados foram analisados por meio de estatística descritiva e inferencial, considerando o nível de significância de 5% (p<0,05. Resultados: Foram concedidas 40 aposentadorias por invalidez. As principais causas da aposentadoria por invalidez foram os transtornos mentais e comportamentais (45,0%, seguidos pelas doenças osteomusculares (25,0%, as doenças do aparelho circulatório (7,5% e as neoplasias (7,5%. Não ouve associação significativa entre as variáveis estudadas. Conclusão: Os grupos de doenças que levaram a aposentadoria por invalidez são as mais comuns entre a população brasileira e passíveis de prevenção.

Quantitative analysis of Fe and Co in Co-substituted magnetite using XPS: The application of non-linear least squares fitting (NLLSF)

Energy Technology Data Exchange (ETDEWEB)

Liu, Hongmei, E-mail: hmliu@gig.ac.cn [CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640 (China); Wei, Gaoling [Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou, 510650 (China); Xu, Zhen [School of Materials Science and Engineering, Central South University, Changsha, 410012 (China); Liu, Peng; Li, Ying [CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China)

2016-12-15

Highlights: • XPS and Auger peak overlapping complicates Co-substituted magnetite quantification. • Disrurbance of Auger peaks was eliminated by non-linear least squares fitting. • Fitting greatly improved the accuracy of quantification for Co and Fe. • Catalytic activity of magnetite was enhanced with the increase of Co substitution. - Abstract: Quantitative analysis of Co and Fe using X-ray photoelectron spectroscopy (XPS) is of important for the evaluation of the catalytic ability of Co-substituted magnetite. However, the overlap of XPS peaks and Auger peaks for Co and Fe complicate quantification. In this study, non-linear least squares fitting (NLLSF) was used to calculate the relative Co and Fe contents of a series of synthesized Co-substituted magnetite samples with different Co doping levels. NLLSF separated the XPS peaks of Co 2p and Fe 2p from the Auger peaks of Fe and Co, respectively. Compared with a control group without fitting, the accuracy of quantification of Co and Fe was greatly improved after elimination by NLLSF of the disturbance of Auger peaks. A catalysis study confirmed that the catalytic activity of magnetite was enhanced with the increase of Co substitution. This study confirms the effectiveness and accuracy of the NLLSF method in XPS quantitative calculation of Fe and Co coexisting in a material.

13C NMR and XPS characterization of anion adsorbent with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse

International Nuclear Information System (INIS)

Cao, Wei; Wang, Zhenqian; Zeng, Qingling; Shen, Chunhua

2016-01-01

Highlights: • 13 C NMR and XPS were successfully used to characterize quaternary ammonium groups in the surface of crop straw based anion adsorbents. • The results obtained from different kinds of crop straw material clearly confirmed the presence of quaternary ammonium groups. • The composition of C-groups and N-groups also were determined by curving fitting of high-resolution XPS C1 and N1 spectra. - Abstract: Despite amino groups modified crop straw has been intensively studied as new and low-cost adsorbent for removal of anionic species from water, there is still a lack of clear characterization for amino groups, especially quaternary ammonium groups in the surface of crop straw. In this study, we used 13 C NMR and XPS technologies to characterize adsorbents with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse. 13 C NMR spectra clearly showed the presence of quaternary ammonium groups in lignocelluloses structure of modified crop straw. The increase of nitrogen observed in XPS survey spectra also indicated the existence of quaternary ammonium group in the surface of the adsorbents. The curve fitting of high-resolution XPS N1s and C1s spectra were conducted to probe the composition of nitrogen and carbon contained groups, respectively. The results showed the proportion of quaternary ammonium group significantly increased in the prepared adsorbent’s surface that was dominated by methyl/methylene, hydroxyl, quaternary ammonium, ether and carbonyl groups. This study proved that 13 C NMR and XPS could be successfully utilized for characterization of quaternary ammonium modified crop straw adsorbents.

Uma investigação dos sentidos de um phrasal verb por meio dos corpora e dicionários on-line

Directory of Open Access Journals (Sweden)

Emiliana Fernandes Bonalumi

2014-06-01

Full Text Available Nesta pesquisa analisamos o uso do phrasal verbs throw up encontrado em dois corpora on-line originalmente escritos em língua inglesa, a saber: British National Corpus (BNC e Corpus of Contemporary American English (COCA, bem como no livro didático adotado em sala de aula New English File Upper-Intermediate, com o suporte dos dicionários on-line Cambridge Online Dictionary e Macmillan Dictionary. Objetivamos identificar, classificar e generalizar o uso e significados do phrasal verb selecionado para a análise nos respectivos corpora on-line em relação ao seu uso e significado no livro didático anteriormente mencionado. Por meio dos corpora e dicionários on-line, o aluno expandirá seu conhecimento acerca do uso e significados de um determinado phrasal verb, como o analisado nesta investigação. Palavras-chave: linguística de corpus; ensino movido por dados; phrasal verbs.

XPS STRUCTURE ANALYSIS OF TiN/TiC BILAYERS PRODUCED BY PULSED VACUUM ARC DISCHARGE

Directory of Open Access Journals (Sweden)

ELISABETH RESTREPO PARRA

2010-01-01

Full Text Available se crecieron bicapas de TiN/TiC sobre sustratos de acero inoxidable 304 usando un sistema de deposición física de vapor asistida por plasma en forma de arco pulsado a dos diferentes temperaturas del sustrato (50º C y150º C. Para el análisis de la composición química se empleó la técnica de la espectroscopía de fotoelectrones de rayos X (XPS. Se observó el comportamiento de las líneas Ti2p, N1s y C1s. Los análisis de energía de enlace confirmaron la conformación de TiN y TiC. Los picos C1s y Ti2p sufrieron un corrimiento a medida que se incrementó el tiempo de esputtering, revelando contaminación debido a la presencia de hidrocarburos. Además, los perfiles de profundidad de las bicapas de TiN/TiC mostraron que las películas crecidas a una temperatura de 150 ° C tienen una capa de TiN más gruesa que las muestras crecidas a 50º C. El nitrógeno se difundió en la capa de TiC y el carbón en la capa de TiN para ambas temperaturas.

Morphological, chemical and structural characterisation of deciduous enamel: SEM, EDS, XRD, FTIR and XPS analysis.

Science.gov (United States)

Zamudio-Ortega, C M; Contreras-Bulnes, R; Scougall-Vilchis, R J; Morales-Luckie, R A; Olea-Mejía, O F; Rodríguez-Vilchis, L E

2014-09-01

The purpose of this study was to characterise the enamel surface of sound deciduous teeth in terms of morphology, chemical composition, structure and crystalline phases. The enamel of 30 human deciduous teeth was examined by: Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). Chemical differences between incisors and canines were statistically evaluated using the Mann-Whitney U test (p ≤ 0.05). Three enamel patterns were observed by SEM: 'mostly smooth with some groves', 'abundant microporosities' and 'exposed prisms'. The average Ca/P molar ratios were 1.37 and 1.03 by EDS and XPS, respectively. The crystallite size determined by XRD was 210.82 ± 16.78 Å. The mean ratio between Ca bonded to phosphate and Ca bonded to hydroxyl was approximately 10:1. The enamel of sound deciduous teeth showed two main patterns: 'mostly smooth with some groves' and 'abundant microporosities'. 'Exposed prisms' was a secondary pattern. There were slight variations among the Ca/P molar ratios found by EDS and XPS, suggesting differences in the mineral content from the enamel surface to the interior. The crystalline phases found in enamel were hydroxyapatite and carbonate apatite, with major type B than type A carbonate incorporation.

XPS investigations on the UV-laser ablation mechanism of poly(ether imide)

Energy Technology Data Exchange (ETDEWEB)

Wambach, J; Kunz, T; Schnyder, B; Koetz, R; Wokaun, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

UV-Laser ablated samples of poly(ether imide) [Kapton{sup TM}] were studied with small-spot XPS. Applying fluences above the threshold level (0.167 J/cm{sup 2}) resulted in the expected behaviour of a decline of both nitrogen and oxygen. Below the threshold level a hint for an altered ablation mechanism was found. (author) 1 fig., 5 refs.

XPS and EPXMA investigation and chemical speciation of aerosol samples formed in LWR core melting experiments

International Nuclear Information System (INIS)

Moers, H.; Jenett, H.; Kaufmann, R.; Klewe-Nebenius, H.; Pfennig, G.; Ache, H.J.

1985-09-01

Aerosol samples consisting of fission products and elements of light water reactor structural materials were collected during simulating in a laboratory scale the heat-up phase of a core melt accident. The aerosol particles were formed in a steam atmosphere at temperatures between 1200 and 1900 0 C of the melting charge. The investigation of the samples by use of X-ray photoelectron spectroscopy (XPS) permitted the chemical speciation of the detected aerosol constituents silver, cadmium, indium, tellurium, iodine, and cesium. A comparison of the elemental analysis results obtained from XPS with those achieved from electron probe X-ray micro analysis (EPXMA) revealed that aerosol particle surface and aerosol particle bulk are principally composed of the same elements and that these compositions vary with release temperature. In addition, quantitative differences between the composition of surface and bulk have only been observed for those aerosol samples which were collected at higher melting charge temperatures. In order to obtain direct information on chemical species below the surface selected samples were argon ion bombarded. Changes in composition and chemistry were monitored by XPS, and the results were interpreted in light of the effects, which were observed when appropriate standard samples were sputtered. (orig.) [de

Multicenter study on costs associated with two surgical procedures: GreenLight XPS 180 W versus the gold standard transurethral resection of the prostate.

Science.gov (United States)

Benejam-Gual, J M; Sanz-Granda, A; Budía, A; Extramiana, J; Capitán, C

2014-01-01

To analyze the costs associated with two surgical procedures for lower urinary tract symptoms secondary to benign prostatic hyperplasia: GreenLight XPS 180¦W versus the gold standard transurethral resection of the prostate. A multicenter, retrospective cost study was carried out from the National Health Service perspective, over a 3-month time period. Costs were broken down into pre-surgical, surgical and post-surgical phases. Data were extracted from records of patients operated sequentially, with IPSS=15, Qmax=15 mL/seg and a prostate volume of 40-80mL, adding only direct healthcare costs (€, 2013) associated with the procedure and management of complications. A total of 79 patients sequentially underwent GL XPS (n: 39) or TURP (n: 40) between July and October, 2013. Clinical outcomes were similar (94.9% and 92.5%, GL XPS and TURP, respectively) without significant differences (P=.67). The average direct cost per patient was reduced by €114 in GL XPS versus TURP patients; the cost was higher in the surgical phase with GL XPS (difference: €1,209; P<.001) but was lower in the post-surgical phase (difference: €-1,351; P<.001). The GreenLight XPS 180-W laser system is associated with a reduction in costs with respect to transurethral resection of prostate in the surgical treatment of LUTS secondary to PBH. This reduction is due to a shorter inpatient length of stay that offsets the cost of the new technology. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

Use of XPS to clarify the Hall coefficient sign variation in thin niobium layers buried in silicon

Energy Technology Data Exchange (ETDEWEB)

Demchenko, Iraida N., E-mail: demch@ifpan.edu.pl [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw (Poland); Lisowski, Wojciech [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland); Syryanyy, Yevgen [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw (Poland); Melikhov, Yevgen [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw (Poland); School of Engineering, Cardiff University, Newport Rd., Cardiff, CF24 3AA (United Kingdom); Zaytseva, Iryna; Konstantynov, Pavlo [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw (Poland); Chernyshova, Maryna [Institute of Plasma Physics and Laser Microfusion, Hery Street 23, 01-497 Warsaw (Poland); Cieplak, Marta Z. [Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw (Poland)

2017-03-31

Highlights: • HR XPS spectra of Nb 3d, Si 2p, O 1s were probed for Si/Nb/Si trilayers prepared by magnetron sputtering to clarify the Hall coefficient variation as a function of Nb layer thickness. • Strong boundary scattering, enhanced by the presence of silicon ions in the layer close to the interface/s is a main factor leading to sign change of the Hall coefficient. • Theoretical concentration/depth profile as a function of sputtering determined by SESSA after optimization of the model system gives good agreement with experiment. - Abstract: Si/Nb/Si trilayers formed with 9.5 and 1.3 nm thick niobium layer buried in amorphous silicon were prepared by magnetron sputtering and studied using XPS depth-profile techniques in order to investigate the change of Hall coefficient sign with thickness. The analysis of high-resolution (HR) XPS spectra revealed that the thicker layer sample has sharp top interface and metallic phase of niobium, thus holes dominate the transport. In contrast, the analysis indicates that the thinner layer sample has a Nb-rich mixed alloy formation at the top interface. The authors suggest that the main effect leading to a change of sign of the Hall coefficient for the thinner layer sample (which is negative contrary to the positive sign for the thicker layer sample) may be related to strong boundary scattering enhanced by the presence of silicon ions in the layer close to the interface/s. The depth-profile reconstruction was performed by SESSA software tool confirming that it can be reliably used for quantitative analysis/interpretation of experimental XPS data.

Relação entre solos afetados por sais e concentração de metais pesados em quatro perímetros irrigados no Ceará

Directory of Open Access Journals (Sweden)

Cleyton S. M. Cunha

Full Text Available RESUMO O trabalho teve como objetivo verificar a relação entre atributos químicos relacionados com a salinidade (CTC, pH, PST e CE e concentrações de metais pesados (Fe, Al, Si, Ti, Mn, Zn, Cr, V, Ni, Cu, Co, B, Pb, Se, Cd, Mo, Zr e suas inter-relações em solos afetados por sais relativo a quatro perímetros irrigados no Ceará. Foram coletadas amostras de solo, de diferentes texturas, nas profundidades de 0–10 e 10-20 cm em 10 pontos dentro de cada perímetro, totalizando oitenta (80 amostras. Foram utilizadas a análise de correlação canônica (ACC e a análise fatorial com extração dos fatores em componentes principais (AF para verificar as possíveis relações entre os dois conjuntos de variáveis. Os atributos do solo relacionadas com a salinidade contribuíram para explicar as concentrações de metais pesados nos solos dos quatro perímetros irrigados, quando analisados em conjunto; todavia, não foram capazes de explicar quando analisados de forma individual; seguindo a ordem de importância: CTC > pH > PST > CE. Foram verificadas correlações entre os elementos metálicos analisados neste estudo (B, Mo, Si, Zr, Cr, Ni, Pb, Ti, Zn, Cd, Co, Se e Cu com o Fe, Mn, Al, Ti e V, ou, ainda, afinidades geoquímicas entre os elementos.

A dor como quinto sinal vital: utilização da escala de avaliação por enfermeiros de um hospital geral

OpenAIRE

Bottega, Fernanda Hanke; Fontana, Rosane Teresinha

2010-01-01

Pesquisa descritiva, que objetivou descrever as impressões dos enfermeiros sobre o uso de uma escala visual analógica de avaliação da dor em adultos. Os dados foram coletados por meio de um questionário aplicado a 14 enfermeiros de um hospital e analisados mediante análise temática, resultando em seis categorias: a avaliação da dor e sua importância; a avaliação da dor oportunizando humanização do cuidado; a escala da dor medindo subjetividade; a avaliação da dor oportunizando humanização do ...

Evaluación de la calidad de los registros de enfermería en la historia clínica por medio de la auditoría

OpenAIRE

Setz, Vanessa Grespan; D'Innocenzo, Maria

2009-01-01

OBJETIVO: Desse modo o objetivo deste estudo foi avaliar por meio da auditoria, a qualidade dos registros de enfermagem nos prontuários de pacientes atendidos em unidades de um hospital universitário do município de São Paulo. MÉTODOS: O estudo é descritivo, retrospectivo e o método foi pesquisa documental. Dos 424 prontuários analisados entre novembro de 2006 a janeiro de 2007, em diferentes unidades clinicas e cirúrgicas de um hospital universitário, 43,9% se referiam a óbitos e 56,1% a alt...

Quantitative analysis of Si1-xGex alloy films by SIMS and XPS depth profiling using a reference material

Science.gov (United States)

Oh, Won Jin; Jang, Jong Shik; Lee, Youn Seoung; Kim, Ansoon; Kim, Kyung Joong

2018-02-01

Quantitative analysis methods of multi-element alloy films were compared. The atomic fractions of Si1-xGex alloy films were measured by depth profiling analysis with secondary ion mass spectrometry (SIMS) and X-ray Photoelectron Spectroscopy (XPS). Intensity-to-composition conversion factor (ICF) was used as a mean to convert the intensities to compositions instead of the relative sensitivity factors. The ICFs were determined from a reference Si1-xGex alloy film by the conventional method, average intensity (AI) method and total number counting (TNC) method. In the case of SIMS, although the atomic fractions measured by oxygen ion beams were not quantitative due to severe matrix effect, the results by cesium ion beam were very quantitative. The quantitative analysis results by SIMS using MCs2+ ions are comparable to the results by XPS. In the case of XPS, the measurement uncertainty was highly improved by the AI method and TNC method.

Characterization of carbonated serpentine using XPS and TEM

International Nuclear Information System (INIS)

Schulze, Roland K.; Hill, Mary Ann; Field, Robert D.; Papin, Pallas A.; Hanrahan, Robert J.; Byler, Darrin D.

2004-01-01

With the increasing concentration volume of carbon dioxide in the atmosphere, there has been an increasing interest in carbon dioxide sequestration. One method is to store the carbon dioxide in mineral form, reacting solution dissolved CO 2 to precipitate carbonates. In order to understand whether or not such an endeavor is feasible, the carbonation reaction must first be understood. In this study, the surface of ground serpentine, untreated, heat treated and following a carbonation experiment, has been characterized using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results indicate that the mechanism for the reaction involves dissolution of the serpentine through the formation of an amorphous phase and subsequent precipitation of magnesite. The rate limiting step appears to be the diffusion of Mg out of the amorphous phase

Study of electron beam effects on surfaces using x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS)

International Nuclear Information System (INIS)

Gettings, M.; Coad, J.P.

1976-02-01

Discrepancies in the surface analyses of oxidised or heavily contaminated materials have been observed between X-ray Photoelectron Spectroscopy (XPS) and techniques using electron beams (primarily Auger Electron Spectroscopy (AES)). These discrepancies can be ascribed to the influence of the primary electron beam and to illustrate the various types of electron effects different materials were analysed using XPS and Secondary Ion Mass Spectroscopy (SIMS) before and after large area electron bombardment. The materials used included chrome and stainless steels, nickel, platinum, glass and brass. (author)

{sup 13}C NMR and XPS characterization of anion adsorbent with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse

Energy Technology Data Exchange (ETDEWEB)

Cao, Wei, E-mail: weicao@hqu.edu.cn; Wang, Zhenqian; Zeng, Qingling; Shen, Chunhua

2016-12-15

Highlights: • {sup 13}C NMR and XPS were successfully used to characterize quaternary ammonium groups in the surface of crop straw based anion adsorbents. • The results obtained from different kinds of crop straw material clearly confirmed the presence of quaternary ammonium groups. • The composition of C-groups and N-groups also were determined by curving fitting of high-resolution XPS C1 and N1 spectra. - Abstract: Despite amino groups modified crop straw has been intensively studied as new and low-cost adsorbent for removal of anionic species from water, there is still a lack of clear characterization for amino groups, especially quaternary ammonium groups in the surface of crop straw. In this study, we used {sup 13}C NMR and XPS technologies to characterize adsorbents with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse. {sup 13}C NMR spectra clearly showed the presence of quaternary ammonium groups in lignocelluloses structure of modified crop straw. The increase of nitrogen observed in XPS survey spectra also indicated the existence of quaternary ammonium group in the surface of the adsorbents. The curve fitting of high-resolution XPS N1s and C1s spectra were conducted to probe the composition of nitrogen and carbon contained groups, respectively. The results showed the proportion of quaternary ammonium group significantly increased in the prepared adsorbent’s surface that was dominated by methyl/methylene, hydroxyl, quaternary ammonium, ether and carbonyl groups. This study proved that {sup 13}C NMR and XPS could be successfully utilized for characterization of quaternary ammonium modified crop straw adsorbents.

XPS studies of Mg doped GDC (Ce0.8Gd0.2O2-δ) for IT-SOFC

Science.gov (United States)

Tyagi, Deepak; Rao, P. Koteswara; Wani, B. N.

2018-04-01

Fuel Cells have gained much attention as efficient and environment friendly device for both stationary as well as mobile applications. For intermediate temperature SOFC (IT-SOFC), ceria based electrolytes are the most promising one, due to their higher ionic conductivity at relatively lower temperatures. Gd doped ceria is reported to be having the highest ionic conductivity. In the present work, Mg is codoped along with Gd and the electronic structure of the constituents is studied by XPS. XPS confirm that the Cerium is present in +4 oxidation state only which indicates that electronic conduction can be completely avoided.

Formation of carboxy- and amide-terminated alkyl monolayers on silicon(111) investigated by ATR-FTIR, XPS, and X-ray scattering: Construction of photoswitchable surfaces

DEFF Research Database (Denmark)

Rück-Braun, Karola; Petersen, Michael Åxman; Michalik, Fabian

2013-01-01

-FTIR and XPS studies of the fulgimide samples revealed closely covered amide-terminated SAMs. Reversible photoswitching of the headgroup was read out by applying XPS, ATR-FTIR, and difference absorption spectra in the mid-IR. In XPS, we observed a reversible breathing of the amide/imide C1s and N1s signals......We have prepared high-quality, densely packed, self-assembled monolayers (SAMs) of carboxy-terminated alkyl chains on Si(111). The samples were made by thermal grafting of methyl undec-10-enoate under an inert atmosphere and subsequent cleavage of the ester functionality to disclose the carboxylic...... zigzag-like substitution pattern for the ester- and carboxy-terminated monolayer. Hydrolysis of the remaining H-Si(111) bonds at the surface furnished HO-Si(111) groups according to XPS and attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) studies. The amide-terminated alkyl...

Gravidade das coinfecções virais em lactentes hospitalizados com infecção por vírus sincicial respiratório

Directory of Open Access Journals (Sweden)

Milena De Paulis

2011-08-01

Full Text Available OBJETIVO: Comparar a gravidade de infecções causadas por um único vírus (VSR com a gravidade de coinfecções. MÉTODOS: Este estudo avaliou uma coorte histórica de lactentes com infecção aguda por VSR. Secreção de nasofaringe foi coletada de todos os pacientes rotineiramente para pesquisa viral usando técnicas de biologia molecular. Os seguintes desfechos foram analisados: tempo total de internação, duração da oxigenioterapia, admissão em unidade de terapia intensiva e uso de ventilação mecânica. Os resultados foram ajustados para os fatores confundidores (prematuridade, idade e aleitamento materno. RESULTADOS: Foram incluídos no estudo 176 lactentes com idade média de 4,5 meses e diagnósticos de bronquiolite e/ou pneumonia. Cento e vinte e um tinham infecção única por VSR, e 55 tinham coinfecções (24 VSR + adenovírus, 16 VSR + metapneumovírus humano e 15 outras associações menos frequentes. Os quatro desfechos de gravidade avaliados foram semelhantes entre o grupo com infecção única por VSR e os grupos com coinfecções, independente do tipo de vírus associado com o VSR. CONCLUSÃO: As coinfecções virais não parecem alterar o prognóstico de lactentes hospitalizados com infecção aguda por VSR.

ÂNCORAS DE CARREIRA: POR ONDE CAMINHAM AS GERAÇÕES?

Directory of Open Access Journals (Sweden)

Fabio Santarossa Dante

2017-05-01

Full Text Available Frente aos desafios em gestão de pessoas na década presente, os conflitos geracionais alimentam uma discussão sobre quais fatores definem as carreiras e motivam os profissionais. O objetivo deste artigo é apresentar um estudo que identifique tendências de cada geração presente no mercado de trabalho a partir das âncoras de carreira. Ao final do estudo, tais tendências identificadas poderão ser trabalhadas como insumos informacionais a empregadores, organizações e profissionais quanto ao entendimento de expectativas de tais profissionais e âncoras que os direcionam em suas carreiras. Como método de estudo de coleta e análise dos resultados, utilizou-se um questionário desenvolvido por Shein (1996, aplicado a 105 pessoas. Os dados coletados foram analisados em formaquantitativa.Os resultados apresentam que as três gerações estudadas possuem as mesmas primeiras âncoras de carreira (Estilo de Vida, apenas diferenciando-se na segunda e na terceira âncoras, com oportunidades de aprofundamento quanto às tendências atuais.

XPS analysis of aluminosilicate microspheres bioactivity tested in vitro

Energy Technology Data Exchange (ETDEWEB)

Todea, M.; Vanea, E. [Faculty of Physics and Institute of Interdisciplinary Research on Bio-Nano-Sciences, Babes Bolyai University, Cluj-Napoca 400084 (Romania); Bran, S. [University of Medicine and Pharmacy “Iuliu Haţieganu”, Department of Cranio-Maxillofacial Surgery, 400029 Cluj-Napoca (Romania); Berce, P. [Technical University of Cluj-Napoca, Faculty of Machine Building and National Centre of Rapid Prototyping, 400641 Cluj-Napoca (Romania); Simon, S., E-mail: simons@phys.ubbcluj.ro [Faculty of Physics and Institute of Interdisciplinary Research on Bio-Nano-Sciences, Babes Bolyai University, Cluj-Napoca 400084 (Romania)

2013-04-01

The study aims to characterize surface properties of aluminosilicate microspheres incorporating yttrium, with potential biomedical applications. Micrometric particles of spherical shape were obtained by spray drying method. The behavior of aluminosilicate microspheres without yttrium and with yttrium was investigated under in vitro conditions, by seven days incubation in simulated body fluid (SBF). The surface elemental composition and the atomic environments on outermost layer of the microspheres, prior to and after incubation in SBF were evaluated by X-ray photoelectron spectroscopy (XPS) in order to investigate their bioactivity. The results were analyzed to underline the effect of yttrium addition on surface properties of the aluminosilicate microspheres and implicitly on the behavior of the samples in simulated body environments.

XPS and EELS characterization of Mn{sub 2}SiO{sub 4}, MnSiO{sub 3} and MnAl{sub 2}O{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Grosvenor, A.P., E-mail: andrew.grosvenor@usask.ca [Department of Chemistry, University of Saskatchewan, Saskatoon, SK S7N 5C9 (Canada); Bellhouse, E.M., E-mail: erika.bellhouse@arcelormittal.com [Global R & D—Hamilton, ArcelorMittal Dofasco, 1330 Burlington St. E, Hamilton, ON L8N 3J5 (Canada); Korinek, A., E-mail: korinek@mcmaster.ca [Canadian Centre for Electron Microscopy, Brockhouse Institute for Materials Research, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4M1 (Canada); Bugnet, M., E-mail: bugnetm@mcmaster.ca [Canadian Centre for Electron Microscopy, Brockhouse Institute for Materials Research, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4M1 (Canada); McDermid, J.R., E-mail: mcdermid@mcmaster.ca [Steel Research Centre, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4M1 (Canada)

2016-08-30

Graphical abstract: XPS and EELS spectra were acquired from Mn2Al2O4, MnSiO3 and Mn2SiO4 standards and unique features identified that will allow unambiguous identification of these compounds when studying the selective oxidation of advanced steels. - Highlights: • Mn2Al2O4, MnSiO3 and Mn2SiO4 standards were synthesized and characterized using both XPS and EELS. • Unique features in both the XPS high resolution and EELS spectra were identified for all compounds. • The spectra can be used to identify these compounds when studying the selective oxidation of steels. - Abstract: X-ray Photoelectron Spectroscopy (XPS) and Electron Energy Loss Spectroscopy (EELS) are strong candidate techniques for characterizing steel surfaces and substrate-coating interfaces when investigating the selective oxidation and reactive wetting of advanced high strength steels (AHSS) during the continuous galvanizing process. However, unambiguous identification of ternary oxides such as Mn{sub 2}SiO{sub 4}, MnSiO{sub 3}, and MnAl{sub 2}O{sub 4} by XPS or EELS, which can play a significant role in substrate reactive wetting, is difficult due to the lack of fully characterized standards in the literature. To resolve this issue, samples of Mn{sub 2}SiO{sub 4}, MnSiO{sub 3} and MnAl{sub 2}O{sub 4} were synthesized and characterized by XPS and EELS. The unique features of the XPS and EELS spectra for the Mn{sub 2}SiO{sub 4}, MnSiO{sub 3} and MnAl{sub 2}O{sub 4} standards were successfully derived, thereby allowing investigators to fully differentiate and identify these oxides at the surface and subsurface of Mn, Si and Al alloyed AHSS using these techniques.

Thermally Annealed Iron (Oxide) Thin Film on an Alumina Barrier Layer, by XPS

Energy Technology Data Exchange (ETDEWEB)

Madaan, Nitesh; Kanyal, Supriya S.; Jensen, David S.; Vail, Michael A.; Dadson, Andrew; Engelhard, Mark H.; Linford, Matthew R.

2013-09-06

Herein we show characterization of an Fe thin film on Al_2O_3 after thermal annealing under H_2 using Al Ka X-rays. The XPS survey spectrum, narrow Fe 2p scan, and valence band regions are presented. The survey spectrum shows aluminum signals due to exposure of the underlying Al_2O_3 film during Fe nanoparticle formation.

13C NMR and XPS characterization of anion adsorbent with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse

Science.gov (United States)

Cao, Wei; Wang, Zhenqian; Zeng, Qingling; Shen, Chunhua

2016-12-01

Despite amino groups modified crop straw has been intensively studied as new and low-cost adsorbent for removal of anionic species from water, there is still a lack of clear characterization for amino groups, especially quaternary ammonium groups in the surface of crop straw. In this study, we used 13C NMR and XPS technologies to characterize adsorbents with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse. 13C NMR spectra clearly showed the presence of quaternary ammonium groups in lignocelluloses structure of modified crop straw. The increase of nitrogen observed in XPS survey spectra also indicated the existence of quaternary ammonium group in the surface of the adsorbents. The curve fitting of high-resolution XPS N1s and C1s spectra were conducted to probe the composition of nitrogen and carbon contained groups, respectively. The results showed the proportion of quaternary ammonium group significantly increased in the prepared adsorbent's surface that was dominated by methyl/methylene, hydroxyl, quaternary ammonium, ether and carbonyl groups. This study proved that 13C NMR and XPS could be successfully utilized for characterization of quaternary ammonium modified crop straw adsorbents.

Study on the surface chemical properties of UV excimer laser irradiated polyamide by XPS, ToF-SIMS and CFM

International Nuclear Information System (INIS)

Yip, Joanne; Chan, Kwong; Sin, Kwan Moon; Lau, Kai Shui

2002-01-01

Polyamide (nylon 6) was irradiated by a pulsed ultraviolet (UV) excimer laser with a fluence below its ablation threshold. Chemical modifications on laser treated nylon were studied by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (Tof-SIMS) and chemical force microscopy (CFM). XPS study provides information about changes in chemical composition and the chemical-state of atom types on the fiber surface. The high sensitivity of ToF-SIMS to the topmost layers was used to detect crosslinking after the laser treatment. Gold-coated AFM tips modified with -COOH terminated self-assembled alkanethiol monolayers (SAMs) were used to measure adhesion forces on the untreated and laser treated samples. XPS results revealed that the irradiated samples have higher oxygen content than prior to laser irradiation. Tof-SIMS analysis illustrated that carbonyl groups in nylon 6 decrease significantly but hydroxyl groups increase after low-fluence laser irradiation. The adhesion force measurements by CFM showed spatial distribution of hydroxyl groups on nylon 6 after the laser treatment

Efeito sobre a morfologia do esmalte dental e análise físico-química de medicamentos utilizados por pacientes pediátricos com paralisia cerebral

Directory of Open Access Journals (Sweden)

Vanessa Feitosa ALVES

Full Text Available Resumo Introdução Muitos medicamentos pediátricos líquidos são considerados fatores de risco para a estrutura dentária. Esse potencial pode aumentar quando ingeridos de forma crônica, como é o caso do tratamento de algumas condições, tal como a paralisia cerebral. Objetivo Avaliar o efeito sobre a morfologia do esmalte dental e as propriedades físico-químicas de medicamentos de uso contínuo indicados a pacientes infantis com Paralisia Cerebral. Material e método A amostra foi constituída por quatro medicamentos: Fenobarbital (M1, Carbamazepina (M2, Oxcarbazepina (M3 e Domperidona (M4, todos em suspensão oral. Analisaram-se o pH, o teor de Sólidos Solúveis Totais (SST e a viscosidade dos medicamentos. Todos os testes foram realizados em duplicata. Para análise em microscopia eletrônica de varredura (MEV, 15 blocos de esmalte bovino foram distribuídos aleatoriamente e imersos em oxcarbamazepina (n=5, carbamazepina (n=5 e saliva artificial (n=5. Os ciclos de imersão foram feitos por seis dias, durante cinco minutos, duas vezes ao dia, com intervalos de 12 horas, quando ficavam mantidos em saliva artificial. O grupo controle permaneceu em saliva artificial. Os dados foram analisados descritivamente. Resultado Em relação ao pH endógeno, os valores variaram de 2,82 (M3 a 9,60(M1. Para o SST, as médias de maior e menor valor foram, respectivamente, de 20,5% (M3 e 46% (M1. A viscosidade variou de 6,89 mm2/s (M1 a 58 mm2/s (M3. Em MEV, observaram-se alterações sugestivas de perda de estrutura no esmalte dental em oxcarbamazepina e carbamazepina, proveniente da ação dos medicamentos analisados. Conclusão Concluiu-se que os medicamentos líquidos pediátricos analisados, indicados a pacientes com paralisia cerebral, apresentam potencial cariogênico e erosivo, destacando-se a Oxcarbazepina.

Structural, optical, XPS and magnetic properties of Zn particles capped by ZnO nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Morozov, Iu.G., E-mail: yugmor@hotmail.com [Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences, Academician Osipyan Street 8, Chernogolovka, Moscow Region 142432 (Russian Federation); Belousova, O.V. [Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences, Academician Osipyan Street 8, Chernogolovka, Moscow Region 142432 (Russian Federation); Ortega, D., E-mail: daniel.ortega@imdea.org [Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Cantoblanco 28049, Madrid (Spain); Mafina, M.-K., E-mail: m.k.mafina@qmul.ac.uk [School of Engineering and Materials Science, Queen Mary University of London, Mile End, Eng, 231, London E1 4NS (United Kingdom); Kuznetcov, M.V., E-mail: maxim1968@mail.ru [Department of Chemistry, Materials Chemistry Research Centre, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

2015-06-05

Highlights: • Levitation-jet aerosol synthesis of Zn particles capped by ZnO nanoparticles (NPs). • TEM, XRD, UV–vis, FT-IR, Raman, XPS and magnetic characterization of the NPs. • Correlation between unit-cell volume of crystal lattice and maximum magnetization. - Abstract: Spherical zinc particles ranging from 42 to 760 nm in average size and capped with plate-like zinc oxide particles of 10–30 nm in sizes have been prepared by levitation-jet aerosol synthesis through condensation of zinc vapor in an inert/oxidizer gas flow. The nanoparticles have been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), BET measurements, ultra violet visible (UV–vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray electron spectroscopy (XPS), superconducting quantum interference device (SQUID), and vibrating-sample magnetometer (VSM). Magnetic and XRD data indicate that the observed ferromagnetic ordering related to the changes in unit-cell volume of Zn in the Zn/ZnO interface of the nanoparticles. These results are in good correlation with the optical measurements data.

Direct correlations between XPS analyses and growth film by chronopotentiometry on InP in liquid ammonia (−55 °C)

Energy Technology Data Exchange (ETDEWEB)

Gonçalves, A.-M., E-mail: anne-marie.goncalves@uvsq.fr; Njel, C.; Aureau, D.; Etcheberry, A.

2017-01-01

Highlights: • Anodic galvannostatic treatment on n‐InP is carried out in liquid ammonia (−55 °C) under illumination. • Whatever the anodic charge, a phosphazene like film is revealed by XPS without thickening of the layer. • The film growth requires a nucleation step which is followed by a phosphazene coalescence phenomenon in the two dimensions of the surface. • A monolayer film of phosphazene is suggested and an excess of charge is observed which can be assigned to ammonia oxidation. - Abstract: This paper is based on the understanding of the formation of a reproducible polyphosphazene-like film (−[(H{sub 2}N)−P=N]{sub n}−) obtained on InP by anodic treatment in liquid ammonia. The approach is innovative as it combines indications from the coulometric charges and the related chemical information from XPS analyses. Anodic charges are accurately monitored by galvanostatic treatment between 0.05 mC cm{sup −2} and 12.5 mC cm{sup −2}. XPS investigation of the treated surfaces demonstrates the presence of an anodic film on InP. Whatever the spent charge, the specific P{sub 2p} and N{sub 1s} signals agree with the growth of an ultrathin phosphazene layer. From 0.25 mC cm{sup −2} to 12.5 mC cm{sup −2}, a quasi constant XPS response is revealed without thickening of the film. However a gradual chemical evolution of the modified surface is clearly observed for the lower anodic charges (from 0.04 mC cm{sup −2} to 0.5 mC cm{sup −2}). In this case, the surface is entirely recovered by the film as soon as 0.25 mC cm{sup −2} is consumed at the interface. Same atomic surface ratios are indeed revealed indicating that a constant chemical composition is consistent with a polyphosphazene film. On the basis of atomic surface ratios evolutions determined by XPS, a mechanism of the film growth is deduced. It requires a nucleation step which is followed by a phosphazene coalescence phenomenon in the two dimensions of the surface. A final phosphazene

XPS utilization in the characterization of glycerol based polyesters; Utilizacao de XPS na caracterizacao de poliesteres a base de glicerol

Energy Technology Data Exchange (ETDEWEB)

Brioude, M.M.; Miranda, C.S.; Pereira, R.; Ohara, L.; Bargiela, P.; Rocha, M.G.M.C.; Jose, N.M., E-mail: mgcr@ufba.b [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Escola Politecnica. Inst. de Quimica

2010-07-01

X-ray photoelectron spectroscopy-XPS allows the determination of all elements of the periodical table, except hydrogen and helium, and is a very used technique for the polymers characterization, its spectra constitutes a 'fingerprint' of the material. Two samples of polymers were prepared from glycerol and fumaric acid and glycerol and terephthalic acid, with a molar ratio of 1:1 and 1:1.5. The general spectra show the presence of carbon and oxygen, the main components of the polymer. From the binding energies values of the C1s and O1s high resolution spectra it was possible to determine the carbon functional groups. Their concentration were determined and the presence of the aromatic carbon in the terephthalic polyesters was observed, and also similar proportions of aliphatic carbon and ester groups in the fumaric acid polyesters. For both polyesters, an amount of carboxyl group appears, indicating the terminal non-reacted groups. These results were confirmed qualitatively by FTIR. (author)

Representações sociais de família por crianças na cidade de Recife

Directory of Open Access Journals (Sweden)

Fernanda Siqueira Ribeiro

2013-01-01

Full Text Available A pesquisa compreendeu as representações sociais de família compartilhadas por 69 crianças, de 9 a 10 anos, alunos de escolas pública e privada, na cidade de Recife. A perspectiva teórica adotada foi a Teoria das Representações Sociais e a abordagem qualitativa plurimetodológica: questionários de associação livre e hierarquização de palavras; produção de desenho individual da família; e grupos focais. Nos resultados, analisados segundo Bardin e o software EVOC, acessamos o núcleo central das representações sociais de família ancoradas em sentidos positivados próximos ao modelo nuclear. Nos elementos periféricos nos dois contextos de pertença, emergiram múltiplos arranjos familiares e diferenciações funcionais: nas crianças da escola pública, sentidos de família objetivados no afeto e nas figuras de parentesco; e nas crianças da escola privada, sentidos de família idealizados em harmonia e paz, e vínculos afetivos estendidos aos amigos e aos animais de estimação, por vezes, considerados como integrantes da família.

Co-ordination properties of diglycol-amide (DGA) to trivalent curium and lanthanides studied by XAS, XRD and XPS methods

International Nuclear Information System (INIS)

Yaita, T.; Hirata, M.; Narita, H.; Tachimori, S.; Yamamoto, H.; Edelstein, N.M.; Bucher, J.J.; Shuh, D.K.; Rao, L.

2001-01-01

Co-ordination properties of diglycol-amide (DGA) to trivalent curium and to the trivalent lanthanides were studied by the EXAFS, the XRD and the XPS methods. The structural determinations by both the crystal XRD and the solution EXAFS methods showed that the DGA co-ordinated to the trivalent lanthanide ion in a tridentate fashion: co-ordination of three oxygen atoms of each ligand to the metal ion. The bond distances of Er-O (carbonyl) and Er-O (ether) in the Er-DGA complex were 2.35 Angstrom, and 2.46 Angstrom, respectively, while the atom distances of Cm-O (carbonyl) and Cm-O (ether) in the Cm-DGA complex were 2.42 Angstrom and 3.94 Angstrom, respectively from the EXAFS data for the Cm-DGA complex. Accordingly, the DGA would behave only as a semi-tridentate in the co-ordination to trivalent curium in solution. We determined the valence band structures of the Er-DGA complex by the XPS in order to clarify the bond properties of the complex, and assigned the XPS spectrum by using the DV-DS molecular orbital calculation method. (authors)

Avaliação do metabolismo oxidativo e da histopatologia renal e hepática de ovinos intoxicados por cobre e tratados com tetratiomolibdato e vitaminas antioxidantes

OpenAIRE

Rebeca Alves Weigel

2008-01-01

Para avaliar o benefício da utilização parenteral das vitaminas C e/ou E associadas ao quelante de cobre, tetratiomolibdato de amônio (TTM), na recuperação de ovinos com intoxicação cumulativa por cobre (ICC), foram analisados os parâmetros vitais; o metabolismo oxidativo, através das concentrações séricas de ácido úrico e malondialdeído, atividade sanguínea da glutationa reduzida, habilidade de redução férrica plasmática, atividade urinária de N-acetil-β-D-glucosamidase; peso vivo, hema...

Spectroellipsometric, AFM and XPS probing of stainless steel surfaces subjected to biological influences

Science.gov (United States)

Vinnichenko, M.; Chevolleau, Th; Pham, M. T.; Poperenko, L.; Maitz, M. F.

2002-11-01

Surface modification of austenitic stainless steel (SS) 316L after incubation in growing cell cultures and cell-free media as control has been studied. The following treatments were applied: mouse fibrosarcoma cells L929 for 3 and 7 days, polymorphonuclear neutrophils for 3 and 7 days and human osteosarcoma cells SAOS-2 for 7 and 14 days. Cells were enzymatically removed in all cases. The modified surfaces were probed in comparison with untreated ones by means of spectroscopic ellipsometry (SE), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). XPS shows the appearance of the peak of bonded nitrogen at 400.5 eV characteristic for adsorbed proteins on the surface for each type of cells and for the cell-free medium. Migration of Ni in the adsorbed layer is observed in all cases for samples after the cell cultures. The protein layer thickness is ellipsometrically determined to be within 2.5-6.0 nm for all treated samples with parameterization of its optical constants in Cauchy approach. The study showed that for such biological treatments of the SS the protein layer adsorption is the dominating process in the first 2 weeks, which could play a role in the process of corrosion by complex forming properties with metal ions.

Spectroellipsometric, AFM and XPS probing of stainless steel surfaces subjected to biological influences

International Nuclear Information System (INIS)

Vinnichenko, M.; Chevolleau, Th.; Pham, M.T.; Poperenko, L.; Maitz, M.F.

2002-01-01

Surface modification of austenitic stainless steel (SS) 316L after incubation in growing cell cultures and cell-free media as control has been studied. The following treatments were applied: mouse fibrosarcoma cells L929 for 3 and 7 days, polymorphonuclear neutrophils for 3 and 7 days and human osteosarcoma cells SAOS-2 for 7 and 14 days. Cells were enzymatically removed in all cases. The modified surfaces were probed in comparison with untreated ones by means of spectroscopic ellipsometry (SE), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). XPS shows the appearance of the peak of bonded nitrogen at 400.5 eV characteristic for adsorbed proteins on the surface for each type of cells and for the cell-free medium. Migration of Ni in the adsorbed layer is observed in all cases for samples after the cell cultures. The protein layer thickness is ellipsometrically determined to be within 2.5-6.0 nm for all treated samples with parameterization of its optical constants in Cauchy approach. The study showed that for such biological treatments of the SS the protein layer adsorption is the dominating process in the first 2 weeks, which could play a role in the process of corrosion by complex forming properties with metal ions

XPS and μ-Raman study of nanosecond-laser processing of poly(dimethylsiloxane) (PDMS)

Energy Technology Data Exchange (ETDEWEB)

Armyanov, S., E-mail: armyanov@ipc.bas.bg [Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, Sofia 1113 (Bulgaria); Stankova, N.E.; Atanasov, P.A. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Shose, Sofia 1784 (Bulgaria); Valova, E.; Kolev, K.; Georgieva, J. [Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, Sofia 1113 (Bulgaria); Steenhaut, O.; Baert, K.; Hubin, A. [Vrije Universiteit Brussels, Faculty of Engineering, Research Group, SURF “Electrochemical and Surface Engineering” (Belgium)

2015-10-01

Data about the chemical status of poly(dimethylsiloxane) (PDMS) after nanosecond Q-switched Nd:YAG laser treatment with near infrared, visible and ultraviolet radiation are presented. The μ-Raman spectroscopy analyses reveal as irradiation result a new sharp peak of crystalline silicon. In addition, broad bands appear assigned to D band of amorphous carbon and G band of microcrystalline and polycrystalline graphite. The μ-Raman spectra are variable taken in different inspected points in the trenches formed by laser treatment. The XPS surface survey spectra indicate the constituent elements of PDMS: carbon, oxygen and silicon. The spectra of detail XPS scans illustrate the influence of the laser treatment. The position of Si 2p peaks of the treated samples is close to the value of non-treated except that irradiated by 1064 nm 66 pulses, which is shifted by 0.9 eV. Accordingly, a shift by 0.4 eV is noticed of the O 1s peak, which reflects again a stronger oxidation of silicon. The curve fitting of Si 2p and O 1s peaks after this particular laser treatment shows the degree of conversion of organic to inorganic silicon that takes place during the irradiation.

Study of gadolinia-doped ceria solid electrolyte surface by XPS

International Nuclear Information System (INIS)

Datta, Pradyot; Majewski, Peter; Aldinger, Fritz

2009-01-01

Gadolinia-doped ceria (CGO) is an important material to be used as electrolyte for solid oxide fuel cell for intermediate temperature operation. Ceria doped with 10 mol% gadolinia (Ce 0.9 Gd 0.1 O 1.95 ) was prepared by conventional solid state synthesis and found to be single phase by room temperature X-ray diffraction (XRD). The chemical states of the surface of the prepared sample were analyzed by X-ray photoelectron spectroscopy (XPS). Though Gd was present in its characteristic chemical state, Ce was found in both Ce 4+ and Ce 3+ states. Presence of Ce 3+ state was ascribed to the differential yield of oxygen atoms in the sputtering process

Study of the local structure of binary surfaces by electron diffraction (XPS, LEED)

OpenAIRE

Gereová, Katarína

2006-01-01

Study of local structure of binary surface with usage of ultra-thin film of cerium deposited on a Pd (111) single-crystal surface is presented. X-ray photoelectron spectroscopy and diffraction (XPS, XPD), angle resolved UV photoemission spectroscopy (ARUPS) and low energy electron diffraction (LEED) was used for our investigations. LEED and X-ray excited photoemission intensities results represent a surface-geometrical structure. As well, mapping of ultra-violet photoelectron intensities as a...

XPS and Raman study of zinc containing silica microparticles loaded with insulin

Energy Technology Data Exchange (ETDEWEB)

Vanea, E.; Simon, V., E-mail: viorica.simon@phys.ubbcluj.ro

2013-09-01

Zinc–silica microparticles obtained by sol–gel method solely or by combining sol–gel chemistry with freeze-drying and spray-drying procedures were explored as potential insulin drug delivery carriers for their improved loading efficiency. Zinc containing silica hosts of different specific surface area and mean pore volume loaded with insulin under similar conditions were investigated by X-ray photoelectron spectroscopy (XPS) and confocal micro-Raman spectroscopy in order to assess the insulin adherence to these matrices and the biologically active state of the insulin after embedding.

A transferência do poder no império romano: a sucessão de Nerva por Trajano

Directory of Open Access Journals (Sweden)

Alex Aparecido da Costa

2013-01-01

Full Text Available O problema da questão sucessória durante o Alto Império romano chama-nos a atenção, sobretudo, pelo fato de que no período as mudanças dos césares acarretaram não só distúrbios políticos e conflitos militares, elas impuseram também problemas de legitimação que buscaram respaldo nas instituições tradicionais por conta da escassez de mecanismos jurídicos que as amparassem. No caso analisado neste artigo, a partir do estudo do Panegírico de Trajano de Plínio, o Jovem, com o auxílio de uma análise comparativa dos casos da sucessão de Augusto por Tibério e da tentativa de sucessão de Galba por Pisão Liciniano, percebemos que o sucesso de uma solução pacífica obtida através da passagem do poder de Nerva a Trajano por meio da adoção simbolizou o abandono de dois recursos, o dinástico tradicional, e o restrito à aristocracia de Roma e introduziu a opção da escolha do governante para além das fronteiras da Itália. Assim a presença de Trajano como primeiro provincial a tornar-se imperador representou a renúncia de um sistema que reservava o poder aos indivíduos do centro do império e também o fortalecimento político de camadas mais vastas das populações que viviam sob a égide de Roma.

The effect of particle-hole interaction on the XPS core-hole spectrum

International Nuclear Information System (INIS)

Ohno, Masahide; Sjoegren, Lennart

2004-01-01

How the effective particle-hole interaction energy, U, or the polarization effect on a secondary electron in a final two-hole one-particle (2h1p) state created by the Coster-Kronig (CK) transition can solely affect the density of the CK particle states and consequently the core-hole spectral function, is discussed. The X-ray photoelectron spectroscopy (XPS) core-hole spectrum is predominantly governed by the unperturbed initial core-hole energy relative to the zero-point energy. At the latter energy, the real part of the initial core-hole self-energy becomes zero (no relaxation energy shift) and the imaginary part (the lifetime broadening) approximately maximizes. The zero-point energy relative to the double-ionization threshold energy is governed by the ratio of U relative to the bandwidth of the CK continuum. As an example, we study the 5p XPS spectra of atomic Ra (Z=88), Th (Z=90) and U (Z=92). The spectra are interpreted in terms of the change in the unperturbed initial core-hole energy relative to the zero-point energy. We explain why in general an ab initio atomic many-body calculation can provide an overall good description of solid-state spectra predominantly governed by the atomic-like localized core-hole dynamics. We explain this in terms of the change from free atom to metal in both U and the zero-point energy (self-energy)

XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

International Nuclear Information System (INIS)

Omran, Mamdouh; Fabritius, Timo; Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A.; El-Aref, Mortada; Elmanawi, Abd El-Hamid

2015-01-01

Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe 2 O 3 and P 2 O 5 contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe 3+ ) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases

The determination of acid-base properties of polymer surfaces by XPS: Present status and future prospects

International Nuclear Information System (INIS)

Chehimi, M.M.; Delamar, M.; Shahidzadeh-Ahmadi, N.; Arefi-Khonsari, F.; Amouroux, J.; Watts, J.F.

1996-01-01

The use of the molecular probe technique in conjunction with X-ray photoelectron spectroscopy (XPS) for the assessment of acid-base properties of polymer surfaces is reviewed. The method is based on the determination of the concentration and chemical shifts of Lewis acids (bases) sorbed in polymers of basic (acidic) character. In the case of chloroform (Lewis acid) sorbed in polymers of Lewis basic character, C12p binding energy is linearly correlated with ΔH AB , the heat of acid-base complex formation chloroform-polymer. This relationship has been used to determine the acid-base properties of poly(phenylene oxide), a homopolymer, and ammonia plasma-treated polypropylene. This work shows that XPS can now indeed be used to quantitatively assess the acid-base properties of modified polymer surfaces and perhaps be extended to map acid-base properties of polymer surfaces at the micron or submicron scale. copyright 1996 American Institute of Physics

Applications of high lateral and energy resolution imaging XPS with a double hemispherical analyser based spectromicroscope

International Nuclear Information System (INIS)

Escher, M.; Winkler, K.; Renault, O.; Barrett, N.

2010-01-01

The design and applications of an instrument for imaging X-ray photoelectron spectroscopy (XPS) are reviewed. The instrument is based on a photoelectron microscope and a double hemispherical analyser whose symmetric configuration avoids the spherical aberration (α 2 -term) inherent for standard analysers. The analyser allows high transmission imaging without sacrificing the lateral and energy resolution of the instrument. The importance of high transmission, especially for highest resolution imaging XPS with monochromated laboratory X-ray sources, is outlined and the close interrelation of energy resolution, lateral resolution and analyser transmission is illustrated. Chemical imaging applications using a monochromatic laboratory Al Kα-source are shown, with a lateral resolution of 610 nm. Examples of measurements made using synchrotron and laboratory ultra-violet light show the broad field of applications from imaging of core level electrons with chemical shift identification, high resolution threshold photoelectron emission microscopy (PEEM), work function imaging and band structure imaging.

Reciclagem de Cavacos de Titânio para a Deposição de Revestimentos Duros por Soldagem

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José Gedael Fagundes Júnior

2015-03-01

Full Text Available O titânio é um metal nobre e possui excelentes propriedades biomecânicas, podendo assim ser plenamente aceito pelo organismo humano. A grande demanda na utilização de implantes dentários, fabricados a partir de ligas de titânio traz consigo um aumento significativo na geração de resíduos (cavacos, resultantes dos processos de usinagem empregados. Com o objetivo de reduzir os impactos ambientais, soluções alternativas para a reutilização de tais resíduos têm sido estudadas. O carboneto de titânio (TiC possui elevada dureza, o que potencialmente permitiria a sua utilização como reforço em revestimentos antidesgaste aplicados em equipamentos das indústrias sucroalcooleira e mineradoras. Neste trabalho cavacos de ligas a base de titânio foram processados e utilizados como matéria prima para a fabricação de consumíveis experimentais de soldagem. Cordões de solda foram produzidos sobre amostras de aço-carbono por soldagem a arco elétrico com proteção gasosa e eletrodo de tungstênio (tradução do termo inglês GTAW. A caracterização microestrutural do metal de solda foi realizada por MEV e difração de raios-X. O comportamento mecânico dos revestimentos foi analisado por meio de um ultramicrodurômetro digital. Verificou-se que a microestrutura do metal de solda era composta por partículas não prismáticas de alta dureza distribuídas em uma matriz ferrítica. Medidas feitas por microanálise EDS mostraram diferenças na concentração de titânio entre a matriz e as partículas duras, onde maiores teores deste elemento foram identificados. A análise cristalográfica confirmou que houve a formação de carbonetos de titânio envoltos por uma matriz de ferrita.

Secondary electron measurement and XPS characterization of NEG coatings

International Nuclear Information System (INIS)

Sharma, R. K.; Sinha, Atul K.; Gupta, Nidhi; Nuwad, J.; Jagannath,; Gadkari, S. C.; Singh, M. R.; Gupta, S. K.

2014-01-01

Ternary alloy coatings of IVB and VB materials provide many of benefits over traditional material surfaces such as creation of extreme high vacuum(XHV), lower secondary electron yield(SEY), low photon desorption coefficient. XHV (pressure −10 mbar) is very useful to the study of surfaces of the material in as it is form, high energy particle accelerators(LHC, Photon Factories), synchrotrons (ESRF, Ellectra) etc.. Low secondary electron yield leads to very low multi-pacting utilizes to increase beam life time. In this paper preparation of the coatings and a study of secondary electron yield measurement after heating at different temperatures has been shown also results of their surface characterization based on shift in binding energy has been produced using the surface techniques XPS. Stoichiometry of the film was measured by Energy dispersive x-ray analysis (EDX)

Comparison of optical models and signals from XPS and VASE characterized titanium after PBS immersion

Czech Academy of Sciences Publication Activity Database

Penttinen, N.; Hasoň, Stanislav; Silvennoinen, M.; Joska, L.; Silvennoinen, R.

2012-01-01

Roč. 285, č. 6 (2012), s. 965-968 ISSN 0030-4018 Grant - others:GA ČR(CZ) GAP108/10/1782 Program:GA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : permittivity * XPS titanium * diffractive optical element-based sensor Subject RIV: BO - Biophysics Impact factor: 1.438, year: 2012

Morphology and Chemical Composition of soot particles emitted by Wood-burning Cook-Stoves: a HRTEM, XPS and Elastic backscattering Studies.

Science.gov (United States)

Carabali-Sandoval, G. A., Sr.; Castro, T.; Peralta, O.; De la Cruz, W.; Días, J.; Amelines, O.; Rivera-Hernández, M.; Varela, A.; Muñoz-Muñoz, F.; Policroniades, R.; Murillo, G.; Moreno, E.

2014-12-01

The morphology, microstructure and the chemical composition on surface of soot particles were studied by using high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and elastic backscattering spectrometry. In order to obtain freshly soot particles emitted by home-made wood-burning cook stoves, copper grids for Transmission Electron Microscope (TEM) were placed on the last two of an 8-stages MOUDI cascade impactor. The analysis of HRTEM micrographs revealed the nanostructure and the particle size of soot particles. The XPS survey spectra show a large carbon peak around 285 eV and the oxygen signal at 533 eV. Some differences observed in the carbon/oxygen (C/O) ratio of the particles probably depend on the combustion process efficiency of each cook-stove analyzed. The C-1s XPS spectra show an asymmetric broad peak and other with low intensity that corresponds to sp2 and sp3hybridization, which were fitted with a convolution using Gaussian functions. Elastic backscattering technique allows a chemical elemental analysis of samples and confirms the presence of C, O and Si observed by XPS. Additionally, the morphological properties of soot aggregates were analyzed calculating the border-based fractal dimension (Df). Particles exhibit complex shapes with high values of Df. Also, real-time absorption (σabs) and scattering (σsct) coefficients of fine (with aerodynamic diameter < 2.5 µm) soot particles were measured. The trend in σabs and σsct indicate that the cooking process has two important combustion stages which varied in its flaming strength, being vigorous in the first stage and soft in the second one.

Arsenopyrite and pyrite bioleaching: evidence from XPS, XRD and ICP techniques.

Science.gov (United States)

Fantauzzi, Marzia; Licheri, Cristina; Atzei, Davide; Loi, Giovanni; Elsener, Bernhard; Rossi, Giovanni; Rossi, Antonella

2011-10-01

In this work, a multi-technical bulk and surface analytical approach was used to investigate the bioleaching of a pyrite and arsenopyrite flotation concentrate with a mixed microflora mainly consisting of Acidithiobacillus ferrooxidans. X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and X-ray-induced Auger electron spectroscopy mineral surfaces investigations, along with inductively coupled plasma-atomic emission spectroscopy and carbon, hydrogen, nitrogen and sulphur determination (CHNS) analyses, were carried out prior and after bioleaching. The flotation concentrate was a mixture of pyrite (FeS(2)) and arsenopyrite (FeAsS); after bioleaching, 95% of the initial content of pyrite and 85% of arsenopyrite were dissolved. The chemical state of the main elements (Fe, As and S) at the surface of the bioreactor feed particles and of the residue after bioleaching was investigated by X-ray photoelectron and X-ray excited Auger electron spectroscopy. After bioleaching, no signals of iron, arsenic and sulphur originating from pyrite and arsenopyrite were detected, confirming a strong oxidation and the dissolution of the particles. On the surfaces of the mineral residue particles, elemental sulphur as reaction intermediate of the leaching process and precipitated secondary phases (Fe-OOH and jarosite), together with adsorbed arsenates, was detected. Evidence of microbial cells adhesion at mineral surfaces was also produced: carbon and nitrogen were revealed by CHNS, and nitrogen was also detected on the bioleached surfaces by XPS. This was attributed to the deposition, on the mineral surfaces, of the remnants of a bio-film consisting of an extra-cellular polymer layer that had favoured the bacterial action. © Springer-Verlag 2011

An XPS study on the attachment of triethoxsilylbutyraldehyde to two titanium surfaces as a way to bond chitosan

Energy Technology Data Exchange (ETDEWEB)

Martin, Holly J. [Dave C. Swalm School of Chemical Engineering, James Worth Bagley College of Engineering, Mississippi State University, Box 9595, Mississippi State, MS 39762 (United States)], E-mail: hjp2@msstate.edu; Schulz, Kirk H. [Dave C. Swalm School of Chemical Engineering, James Worth Bagley College of Engineering, Mississippi State University, Box 9595, Mississippi State, MS 39762 (United States); Bumgardner, Joel D. [Department of Biomedical Engineering, Herff College of Engineering, University of Memphis, 330 Engineering Technology Building, Memphis, TN 38152 (United States); Walters, Keisha B. [Dave C. Swalm School of Chemical Engineering, James Worth Bagley College of Engineering, Mississippi State University, Box 9595, Mississippi State, MS 39762 (United States)

2008-05-30

A bioactive coating has the ability to create a strong interface between bone tissue and implant. Chitosan, a biopolymer derived from the exoskeletons of shellfish, exhibits many bioactive properties that make it an ideal material for use as a coating such as antibacterial, biodegradable, non-toxic, and the ability to attract and promote bone cell growth and organized bone formation. A previous study reported on the bonding of chitosan to a titanium surface using a three-step process. In the current study, 86.4% de-acetylated chitosan coatings were bound to implant quality titanium in a two-step process that involved the deposition of triethoxsilylbutyraldehyde (TESBA) in toluene, followed by a reaction between the aldehyde of TESBA with chitosan. The chitosan coatings were examined on two different metal treatments to determine if any major differences in the ability of titanium to bind chitosan could be detected. The surface of the titanium metal and the individual reaction steps were examined using X-ray photoelectron spectroscopy (XPS). Following the deposition of TESBA, significant changes were seen in the amounts of oxygen, silicon, carbon, and titanium present on the titanium surface, which were consistent with the anticipated reaction steps. It was demonstrated that more TESBA was bound to the piranha-treated titanium surface as compared to the passivated titanium surface. The two different silane molecules, aminopropyltriethoxysilane (APTES) and TESBA, did not affect the chemistry of the resultant chitosan films. XPS showed that both the formation of unwanted polysiloxanes and the removal of the reactive terminal groups were prevented by using toluene as the carrier solvent to bond TESBA to the titanium surfaces, instead of an aqueous solvent. Qualitatively, the chitosan films demonstrated improved adhesion after using toluene, as the films remained attached to the titanium surface even when placed under the ultra-high vacuum necessary for XPS, unlike the

An XPS study on the attachment of triethoxsilylbutyraldehyde to two titanium surfaces as a way to bond chitosan

International Nuclear Information System (INIS)

Martin, Holly J.; Schulz, Kirk H.; Bumgardner, Joel D.; Walters, Keisha B.

2008-01-01

A bioactive coating has the ability to create a strong interface between bone tissue and implant. Chitosan, a biopolymer derived from the exoskeletons of shellfish, exhibits many bioactive properties that make it an ideal material for use as a coating such as antibacterial, biodegradable, non-toxic, and the ability to attract and promote bone cell growth and organized bone formation. A previous study reported on the bonding of chitosan to a titanium surface using a three-step process. In the current study, 86.4% de-acetylated chitosan coatings were bound to implant quality titanium in a two-step process that involved the deposition of triethoxsilylbutyraldehyde (TESBA) in toluene, followed by a reaction between the aldehyde of TESBA with chitosan. The chitosan coatings were examined on two different metal treatments to determine if any major differences in the ability of titanium to bind chitosan could be detected. The surface of the titanium metal and the individual reaction steps were examined using X-ray photoelectron spectroscopy (XPS). Following the deposition of TESBA, significant changes were seen in the amounts of oxygen, silicon, carbon, and titanium present on the titanium surface, which were consistent with the anticipated reaction steps. It was demonstrated that more TESBA was bound to the piranha-treated titanium surface as compared to the passivated titanium surface. The two different silane molecules, aminopropyltriethoxysilane (APTES) and TESBA, did not affect the chemistry of the resultant chitosan films. XPS showed that both the formation of unwanted polysiloxanes and the removal of the reactive terminal groups were prevented by using toluene as the carrier solvent to bond TESBA to the titanium surfaces, instead of an aqueous solvent. Qualitatively, the chitosan films demonstrated improved adhesion after using toluene, as the films remained attached to the titanium surface even when placed under the ultra-high vacuum necessary for XPS, unlike the

O acesso a informacao sobre higiene bucal e as perdas dentarias por carie entre adultos

Directory of Open Access Journals (Sweden)

Desiree Sant'Ana Haikal

2014-01-01

Full Text Available Objetivou-se testar a associação entre perdas dentárias por cárie (PDC e variáveis relativas ao acesso a informações em saúde bucal. Foram analisados dados de 780 adultos (35-44 anos participantes de um estudo epidemiológico. A variável dependente foi o total de PDC e as independentes foram reunidas em blocos de variáveis: demográficas e socioeconômicas; utilização dos serviços odontológicos; acesso a informações em saúde bucal (informações sobre como evitar problemas bucais, sobre higiene bucal e sobre dieta e; comportamentais. Conduziu-se regressão linear múltipla hierarquizada. O número médio de PDC foi de 7,03 (EP= 0,31 e 83% dos adultos haviam perdido algum dente por cárie. As PDC foram maiores entre os mais velhos, os com menor escolaridade, as mulheres, os que raramente ou nunca receberam informações sobre higiene bucal, os que escovavam os dentes uma vez ou menos ao dia e entre os que não usavam fio dental. Adultos que raramente/nunca receberam informações dos serviços odontológicos sobre higiene bucal perderam 2,15 dentes a mais por cárie que aqueles que sempre/frequentemente receberam tais informações (p = 0,000. Assim, sugere-se que a garantia do acesso à informação deva ser incentivada a fim de contribuir com maior equidade em saúde bucal.

An IR and XPS spectroscopy assessment of the physico-chemical surface properties of alumina–YAG nanopowders

Energy Technology Data Exchange (ETDEWEB)

Spina, Giulia; Bonelli, Barbara, E-mail: barbara.bonelli@polito.it; Palmero, Paola, E-mail: paola.palmero@polito.it; Montanaro, Laura

2013-12-16

Well-dispersed nano-crystalline transition alumina suspensions were mixed with yttrium chloride aqueous solutions, with the aim of producing by spray-drying Al{sub 2}O{sub 3}–Y{sub 3}Al{sub 5}O{sub 12} (YAG) composite powders of increasing YAG vol.%. Two samples were prepared, with different Y content, corresponding to 5 and 20 YAG vol.%, respectively. Both samples were then treated at either 600 or 1150 °C. The obtained powders were characterized by X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infra Red (FT-IR) spectroscopy and compared to three reference samples: commercial nano-crystalline transition alumina, YAG and Y{sub 2}O{sub 3}. YAG powders were obtained by co-precipitation route whereas Y{sub 2}O{sub 3} powders were yielded by spray-drying of a yttrium chloride aqueous solution. Modification of physico-chemical properties of the surface of alumina nanoparticles were assessed by combining XPS and FT-IR spectroscopies. On the basis of the results obtained, a possible model is proposed for the structure of the obtained composites, in which Y basically reacts with more acidic hydroxyls of alumina, by forming Y-rich surface grains, the extension of which depends on the thermal treatment. - Highlights: • Al{sub 2}O{sub 3}–Y{sub 3}Al{sub 5}O{sub 12} (YAG) composite nanopowders were prepared by spray drying. • Combined XPS and IR spectroscopy: effective tools to study surface modifications. • Y reacts with more acidic hydroxyls at alumina surface. • Y-rich surface grains form: their extension depends on the thermal treatment.

Condicionamento térmico primário de instalações rurais por meio de diferentes tipos de cobertura

Directory of Open Access Journals (Sweden)

Thaisa A. Carneiro

2015-11-01

Full Text Available RESUMOObjetivou-se, com este trabalho, avaliar o conforto térmico proporcionado por diferentes tipos de cobertura, com base nas análises térmicas e nos índices de conforto térmico humano e zootécnico. A pesquisa foi realizada no período de 20 de março a 29 de maio de 2014, na UFRPE, no município de Recife, PE. Os tipos de cobertura analisados foram: telha de fibrocimento (Tfib, telha reciclada (Trec, telhado verde, grama, Zoysia japonica (Tgra e telhado verde, amendoim, Arachis repens (Tame, com quatro repetições cada um; as variáveis meteorológicas foram registradas interna e externamente aos modelos. A análise térmica das coberturas foi realizada por meio de imagens termográficas e o conforto térmico das instalações foi obtido por meio dos índices de conforto, carga térmica radiante, índice de temperatura de globo negro e umidade, índice de conforto humano, índice de temperatura e umidade e temperatura efetiva. Os telhados verdes (Tame; Tgra reduziram a temperatura da superfície interna das coberturas (5,3 e 4,4 ºC, promoveram maior atenuação da temperatura dos ambientes (1,37 e 1,35 ºC e, consequentemente, promoveram também maior conforto térmico, em comparação com a Tfib e Trec.

Uso da proteção do complexo dentino-pulpar por discentes de odontologia

Directory of Open Access Journals (Sweden)

Daiane Casarin

2016-10-01

Full Text Available A proteção do complexo dentino pulpar depende de vários fatores, dentre eles, a idade do paciente, a condição pulpar prévia e a profundidade da lesão cariosa ou mesmo do preparo cavitário. Os materiais utilizados para a proteção, por sua vez, devem ser biocompatíveis, ter capacidade de induzir a formação de dentina reparadora dentre outros requisitos. O objetivo deste estudo foi conhecer o material de proteção do complexo dentino pulpar utilizado pelos discentes de odontologia tanto em nível de graduação, bem como em nível de pós-graduação. A metodologia utilizada foi quantitativa observacional do tipo descritiva e não probabilística, a qual envolveu 125 estudantes do último ano de graduação em odontologia e cirurgiões dentistas cursando pós-graduação em Dentística Restauradora em centros de estudos da cidade de Passo Fundo. A coleta de dados foi realizada por meio de um questionário adaptado de Takanashi (4 e os resultados foram analisados descritivamente no Excel, sendo que para cavidades rasas 88,8 % dos profissionais usam técnica adesiva convencional, cavidades médias 60,8% também opta por técnica adesiva convencional, para cavidades profundas 50,4% usa Hidróxido de Cálcio e nos casos de exposição pulpar 59,2% faz uso de pó de Hidróxido de Cálcio. Pode-se concluir que o hidróxido de cálcio foi o material de proteção pulpar mais usado tanto nas cavidades profundas, bem como, nas com exposição pulpar, já em cavidades médias e rasas a maioria optou por técnica adesiva convencional.

XPS and TEM study of W-DLC/DLC double-layered film

International Nuclear Information System (INIS)

Takeno, Takanori; Komiyama, Takao; Miki, Hiroyuki; Takagi, Toshiyuki; Aoyama, Takashi

2009-01-01

A double-layered film of tungsten-containing diamond-like carbon (W-DLC) and DLC, (W-DLC)/DLC, was investigated. A film of 1.6 μm in thickness was deposited onto silicon substrate. The investigate double-layered coating was deposited by using the combination of PECVD and co-sputtering of tungsten metal target. Structure, interface and chemical bonding state of the investigated film were analyzed by Transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). From the results of the analyses, the structure of double-layered film is that amorphous phase of carbon is continued from DLC to W-DLC and tungsten metal clusters are dispersed in W-DLC layer.

EXAFS and XPS Study of Rutile-Type Difluorides of First-Row Transition Metals

International Nuclear Information System (INIS)

Murai, Kei-ichiro; Suzuki, Yohei; Moriga, Toshihiro; Yoshiasa, Akira

2007-01-01

Although most rutile-type difluorides (MnF2, CoF2 and NiF2) have a positive thermal expansion coefficient, FeF2 has a negative thermal expansion (NTE) along the c-axis in the high temperature region. In this study, we give an explanation of that behavior with Extended X-ray Absorption Fine Structure (EXAFS) and X-ray Photoelectron Spectroscopy (XPS) techniques. From EXAFS results, it has become apparent that the length of the share-edge (Fe-Fe) of FeF6 octahedra increased with the rise of temperature in the high temperature region. We have revealed that the force constant between nearest neighbor atoms (Fe-F) was much larger than that between second-nearest neighbor atoms (Fe-Fe) in FeF2. In XPS measurements, it was discovered that the peak of F 1s of FeF2 was located at the lowest binding energy position as compared to that of other difluorides. This means that the charge density around the F atom in FeF2 was higher than that in other difluorides. It follows from this that the share-edge repulsive force in FeF2 is larger than that in other difluorides. On account of the large repulsive force and the large force constant between nearest neighbor atoms, Fe atoms are attracted to share-edge with the rise of temperature

Investigation of CoPd alloys by XPS and EPES using the pattern recognition method

Czech Academy of Sciences Publication Activity Database

Lesiak, B.; Zemek, Josef; Jiříček, Petr; Jozwik, A.

2007-01-01

Roč. 428, - (2007), s. 190-196 ISSN 0925-8388 R&D Projects: GA ČR GA202/06/0459 Institutional research plan: CEZ:AV0Z10100521 Keywords : CoPd alloys * x-ray photoelectron spectroscopy (XPS) * elastic peak electron spectroscopy (EPES) * pattern recognition method * fuzzy k-nearest neighbour rule (fkNN) * quantitative analysis * surface segregation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.455, year: 2007

Lead-silicate glass surface sputtered by an argon cluster ion beam investigated by XPS

Czech Academy of Sciences Publication Activity Database

Zemek, Josef; Jiříček, Petr; Houdková, Jana; Jurek, Karel; Gedeon, O.

2017-01-01

Roč. 469, Aug (2017), s. 1-6 ISSN 0022-3093 R&D Projects: GA MŠk LM2015088; GA ČR(CZ) GA15-12580S Institutional support: RVO:68378271 Keywords : lead-silicate glass * XPS * BO * NBO * Argon duster ion beam sputtering * X-ray irradiation Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.124, year: 2016

Análise do método de medição de viscosidade de líquidos por ultra-som usando a reflexão de ondas de cisalhamento.

OpenAIRE

Édiguer Enrique Franco Guzmán

2006-01-01

Neste trabalho é analisada a medição de viscosidade de líquidos por ultrasom pelo método da reflexão de ondas de cisalhamento. O método baseiase na medição da magnitude e fase do coeficiente de reflexão quando as ondas de cisalhamento incidem na interface entre um sólido e o líquido testado. Foram analisados os conceitos teóricos do método da medição de viscosidade e desenvolvida a metodologia experimental a fim de evitar a influência indesejada de fatores externos, como a temperatura e a ins...

A comparative study of Mg and Pt contacts on semi-insulating GaAs: Electrical and XPS characterization

Energy Technology Data Exchange (ETDEWEB)

Dubecký, F., E-mail: elekfdub@savba.sk [Institute of Electrical Engineering, SAS, Dúbravská cesta 9, Bratislava, SK-84104 (Slovakia); Kindl, D.; Hubík, P. [Institute of Physics CAS, v.v.i., Cukrovarnická 10, CZ-16200 Prague (Czech Republic); Mičušík, M. [Polymer Institute, SAS, Dúbravská cesta 9, Bratislava, SK-84541 (Slovakia); Dubecký, M. [Department of Physics, Faculty of Science, University of Ostrava, 30. dubna 22, CZ-70103 Ostrava 1 (Czech Republic); Boháček, P.; Vanko, G. [Institute of Electrical Engineering, SAS, Dúbravská cesta 9, Bratislava, SK-84104 (Slovakia); Gombia, E. [IMEM-CNR, Parco area delle Scienze 37/A, Parma, I-43010 (Italy); Nečas, V. [Faculty of Electrical Engineering and Information Technology, SUT, Ilkovičova 3, Bratislava, SK-81219 (Slovakia); Mudroň, J. [Department of Electronics, Academy of Armed Forces, Demänová 393, Liptovský Mikuláš, SK-03106 (Slovakia)

2017-02-15

Highlights: • Explored were diodes with full-area low/high work function metal contacts on semi-insulating GaAs (S). • The Mg-S-Mg diode is promising for radiation detectors for its low high-field current. • The XPS analysis of Mg-S interface shows presence of MgO instead of Mg metal. - Abstract: We present a comparative study of the symmetric metal-SI GaAs-metal (M-S-M) diodes with full-area contacts on both device sides, in order to demonstrate the effect of contact metal work function in a straightforward way. We compare the conventional high work function Pt contact versus the less explored low work function Mg contact. The Pt-S-Pt, Mg-S-Mg and mixed Mg-S-Pt structures are characterized by the current-voltage measurements, and individual Pt-S and Mg-S contacts are investigated by the X-ray photoelectron spectroscopy (XPS). The transport measurements of Mg-S-Pt structure show a significant current decrease at low bias while the Mg-S-Mg structure shows saturation current at high voltages more than an order of magnitude lower with respect to the Pt-S-Pt reference. The phenomena observed in Mg-containing samples are explained by the presence of insulating MgO layer at the M-S interface, instead of the elementary Mg, as confirmed by the XPS analysis. Alternative explanations of the influence of MgO layer on the effective resistance of the structures are presented. The reported findings have potential applications in M-S-M sensors and radiation detectors based on SI GaAs.

Temperature dependent structural, luminescent and XPS studies of CdO:Ga thin films deposited by spray pyrolysis

International Nuclear Information System (INIS)

Moholkar, A.V.; Agawane, G.L.; Sim, Kyu-Ung; Kwon, Ye-bin; Choi, Doo Sun; Rajpure, K.Y.; Kim, J.H.

2010-01-01

Research highlights: → The CdO:Ga thin films seems an alternative to traditional TCO materials used in photovoltaic applications. This work deals the effect of deposition temperature on sprayed CdO:Ga films with respect to the structural, luminescent and XPS studies. → The crystalline quality of the GCO films improves with deposition temperature. → The oxygen vacancies are responsible for n-type conductivity and green emission. → The minimum resistivity, highest carrier concentration and mobility are 1.9 x 10 -4 Ω cm, 11.7 x 10 21 cm -3 and 27.64 cm 2 V -1 s -1 , respectively. - Abstract: The structural, compositional, photoluminescent and XPS properties of CdO:Ga thin films deposited at temperatures ranging from 275 to 350 o C, using spray pyrolysis are reported. X-ray diffraction characterization of as-deposited GCO thin films reveals that films are of cubic structure with a (2 0 0) preferred orientation. The crystalline quality of the GCO films improves and the grain size increases with deposition temperature. The EDS analyses confirm oxygen deficiency present in the film and are responsible for n-type conductivity. The photoluminescence spectra demonstrated that the green emission peaks of CdO thin films are centered at 482 nm. The relative intensity of these peaks is strongly dependent on the deposition temperature. Oxygen vacancies are dominant luminescent centers for green emission in CdO thin films. The XPS measurement shows the presence of Cd, Ga, O and C elements and confirms that CdO:Ga films are cadmium-rich.

Identificação do circovírus suíno tipo 2 por reação em cadeia da polimerase e por imunoistoquímica em tecidos suínos arquivados desde 1988 no Brasil

Directory of Open Access Journals (Sweden)

Ciacci-Zanella Janice Reis

2006-01-01

Full Text Available A síndrome multissistêmica do definhamento dos suínos (SMDS é uma doença de importância econômica causada pelo circovírus suíno tipo 2 (PCV2. Uma pesquisa retrospectiva foi realizada em amostras de órgãos de suínos fixados em blocos de parafina arquivados, que haviam sido submetidos à Embrapa Suínos e Aves entre 1985 e 1998 para o diagnóstico histopatológico. Vinte e cinco casos foram selecionados com base nas lesões histológicas características da SMDS, tais como linfoadenopatia, pneumonia intersticial, hepatite e nefrite intersticial. A presença de PCV2 nos cortes histológicos foi pesquisada por reação em cadeia da polimerase interna (nested-PCR, na qual utilizou-se primers específicos para a seqüência da ORF2 do PCV2 e também por imunoistoquímica, utilizando um anticorpo monoclonal específico para o capsídeo do PCV2. O DNA viral e os antígenos específicos do PCV2 foram detectados em amostras de tecidos de dois dos 25 casos analisados, sendo um desses datado de 1988. Esses resultados indicam que o PCV2 já estava presente no Brasil desde 1988.

Characterization of Desulfovibrio desulfuricans biofilm on high-alloyed stainless steel: XPS and electrochemical studies

Energy Technology Data Exchange (ETDEWEB)

Dec, Weronika [Institute of Industrial Organic Chemistry, Branch Pszczyna, Doświadczalna Street 27, 43-200 Pszczyna (Poland); Mosiałek, Michał; Socha, Robert P. [Jerzy Haber Institute of Catalysis and Surface Chemistry PAS, Niezapominajek Street 8, 30-239 Kraków (Poland); Jaworska-Kik, Marzena [Department of Biopharmacy, Medical University of Silesia, Jedności Street 8, 41-200 Sosnowiec (Poland); Simka, Wojciech [Faculty of Chemistry, Silesian University of Technology, B. Krzywoustego 6 Street, 44-100 Gliwice (Poland); Michalska, Joanna, E-mail: joanna.k.michalska@polsl.pl [Faculty of Chemistry, Silesian University of Technology, B. Krzywoustego 6 Street, 44-100 Gliwice (Poland)

2017-07-01

Results on D. desulfuricans biofilm formation on austenitic-ferritic duplex (2205 DSS) and superaustenitic (904L) stainless steels are presented. Surface characterization including the structure, configuration and chemical composition of biofilms were carried out using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Electrochemical impedance spectroscopy (EIS) measurements were used to monitor the attachment activity of bacteria on the steels' surface and to determine the effect of bacteria on passivity. It was proved that investigated steels are rapidly colonized by bacteria. The presence of biofilm caused significant ennoblement of 904L steel surface, while retarded the attainment of high passive state of 2205 DSS. XPS analysis revealed significant sulphidation of the biofilm and its layered structure. Accumulation of sulphides and hydroxides was proved in the outermost layer, while the increasing contents of disulphides, organometallic and C-N bonds were detected in the internal part of the biofilm. Irreversible bondings between steel matrix and biofilm had also been observed. - Highlights: • High-alloyed steels are rapidly colonized by sulphate-reducing bacteria. • Higher Ni content stimulates more intensive biofilm growth. • Extracellular polymeric substances indelibly bind to the high-alloyed steels. • Sulphate-reducing bacteria caused irreversible sulphidation of passive films.

Characterization of Desulfovibrio desulfuricans biofilm on high-alloyed stainless steel: XPS and electrochemical studies

International Nuclear Information System (INIS)

Dec, Weronika; Mosiałek, Michał; Socha, Robert P.; Jaworska-Kik, Marzena; Simka, Wojciech; Michalska, Joanna

2017-01-01

Results on D. desulfuricans biofilm formation on austenitic-ferritic duplex (2205 DSS) and superaustenitic (904L) stainless steels are presented. Surface characterization including the structure, configuration and chemical composition of biofilms were carried out using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Electrochemical impedance spectroscopy (EIS) measurements were used to monitor the attachment activity of bacteria on the steels' surface and to determine the effect of bacteria on passivity. It was proved that investigated steels are rapidly colonized by bacteria. The presence of biofilm caused significant ennoblement of 904L steel surface, while retarded the attainment of high passive state of 2205 DSS. XPS analysis revealed significant sulphidation of the biofilm and its layered structure. Accumulation of sulphides and hydroxides was proved in the outermost layer, while the increasing contents of disulphides, organometallic and C-N bonds were detected in the internal part of the biofilm. Irreversible bondings between steel matrix and biofilm had also been observed. - Highlights: • High-alloyed steels are rapidly colonized by sulphate-reducing bacteria. • Higher Ni content stimulates more intensive biofilm growth. • Extracellular polymeric substances indelibly bind to the high-alloyed steels. • Sulphate-reducing bacteria caused irreversible sulphidation of passive films.

Studies of irradiated zircaloy fuel sheathing using XPS

Energy Technology Data Exchange (ETDEWEB)

Chan, P K; Irving, K G [Atomic Energy of Canada Ltd., Chalk River, ON (Canada); Hocking, W H; Duclos, A M; Gerwing, A F [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

1996-12-31

The preliminary results reported here support the hypothesis that CANLUB graphite coating reduces the rate at which oxygen can react with fuel sheathing. X-ray photoelectron spectroscopic (XPS) characterization of Zircaloy sheathing obtained from extended-burnup Bruce-type elements (BDL-406-XY (555 MW.h/kgU) and BDL-406-AAH (731 MW.h/kgU)) irradiated in NRU indicates that CANLUB may reduce fuel sheath oxidation, and hence that fission-liberated oxygen may remain in the fuel. Chemical shifts in the Zr 3d spectra suggest that a stoichiometric (ZrO{sub 2}) oxide film was formed only on Zircaloy in direct contact with fuel. Particulate fuel adhering to the sheath was also determined to be systematically more oxidized on surfaces with CANLUB than on those without it. The unique association of tin on sheathing specimens with the non-CANLUB-coated specimens might also suggest that the tin had segregated from the sheathing. It must be emphasized that further experiments are required to better define the effect of CANLUB on fuel oxidation. (author). 14 refs., 1 tab., 3 figs.

Studies of irradiated zircaloy fuel sheathing using XPS

International Nuclear Information System (INIS)

Chan, P.K.; Irving, K.G.; Hocking, W.H.; Duclos, A.M.; Gerwing, A.F.

1995-01-01

The preliminary results reported here support the hypothesis that CANLUB graphite coating reduces the rate at which oxygen can react with fuel sheathing. X-ray photoelectron spectroscopic (XPS) characterization of Zircaloy sheathing obtained from extended-burnup Bruce-type elements (BDL-406-XY (555 MW.h/kgU) and BDL-406-AAH (731 MW.h/kgU)) irradiated in NRU indicates that CANLUB may reduce fuel sheath oxidation, and hence that fission-liberated oxygen may remain in the fuel. Chemical shifts in the Zr 3d spectra suggest that a stoichiometric (ZrO 2 ) oxide film was formed only on Zircaloy in direct contact with fuel. Particulate fuel adhering to the sheath was also determined to be systematically more oxidized on surfaces with CANLUB than on those without it. The unique association of tin on sheathing specimens with the non-CANLUB-coated specimens might also suggest that the tin had segregated from the sheathing. It must be emphasized that further experiments are required to better define the effect of CANLUB on fuel oxidation. (author). 14 refs., 1 tab., 3 figs

The assessment of metal surface cleanliness by XPS

CERN Document Server

Scheuerlein, C

2006-01-01

The most commonly used quantity to characterize surface cleanliness through X-ray photoemission spectroscopy (XPS) measurements is the so-called relative atomic surface concentration of carbon (at.% C). We have investigated the relationship between at.% C values and the C 1s peak area on Cu and we find a nearly linear behaviour in the range 15–80 at.% C. Correction factors for the measured at.% C values that enable a comparison of the cleanliness level of different materials, notably Cu, Al and stainless steel, have been determined experimentally. The influence of the storage time and method on the degree of re-contamination of initially clean Cu has been examined. The carbon contamination on clean metallic Cu increases abruptly to some 20 at.% C upon air exposure and continues to increase with storage time in air. Storage in polymer bags can lead to up to 70 at.% C after 1 month, whereas storage in aluminium foil can preserve an acceptable surface cleanliness for a similar storage time.

An XPS study on ruthenium compounds and catalysts

International Nuclear Information System (INIS)

Bianchi, C.L.; Ragaini, V.; Cattania, M.G.

1991-01-01

The binding energy (BE) of the relevant peaks of several ruthenium compounds have been measured with a monochromatic small spot XPS. The BE of the 3d 5/2 level of ruthenium is in the range 279.91-282.88 eV. The variation of BE is due either to the variation of the oxidation state or to the different counter-ion. A series of catalysts with varying amounts of ruthenium supported on alumina and prepared using different precursors was also analyzed. The presence of more ruthenium species other than the metal was observed. On the basis of the values previously obtained on unsupported compounds, the species with higher BE were assigned to oxides. On all the samples prepared from RuCl 3 , an additional peak at a very high BE (283.79 eV) has been observed. This peak is related to the presence of chlorine on the surface: it is suggested that it is related to a charge transfer interaction. The influence of this species on the CO reactivity in the Fischer-Tropsch reaction is discussed. (orig.)

XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

Energy Technology Data Exchange (ETDEWEB)

Omran, Mamdouh, E-mail: mamdouh.omran@oulu.fi [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); Fabritius, Timo [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A. [Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); El-Aref, Mortada; Elmanawi, Abd El-Hamid [Geology Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

2015-08-01

Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe{sub 2}O{sub 3} and P{sub 2}O{sub 5} contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe{sup 3+}) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases.

An XPS study of tarnishing of a gold mask from a pre-Columbian culture

International Nuclear Information System (INIS)

Bastidas, D.M.; Cano, E.; Gonzalez, A.G.; Fajardo, S.; Lleras-Perez, R.; Campo-Montero, E.; Belzunce-Varela, F.J.; Bastidas, J.M.

2008-01-01

The tarnishing originated on a hammered gold mask was analysed. Red tarnishing was observed after three years of storage in an indoor environment in the Gold Museum of Banco de la Republica, Bogota, Colombia. Silver sulphide (Ag 2 S) and silver sulphate (Ag 2 SO 4 ) compounds were identified as the origin of the tarnishing phenomenon, which is attributed to environmental contamination. Atomic absorption spectroscopy (AAS) and X-ray photoelectron spectroscopy (XPS) techniques were used

Formation of complexes between functionalized chitosan membranes and copper: A study by angle resolved XPS

Energy Technology Data Exchange (ETDEWEB)

Jurado-López, Belén [Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga (Spain); Vieira, Rodrigo Silveira [Chemical Engineering Department, Universidade Federal do Ceará, UFC, 60455-760 Fortaleza, CE (Brazil); Rabelo, Rodrigo Balloni; Beppu, Marisa Masumi [School of Chemical Engineering, University of Campinas, UNICAMP, P.O. Box 6066, 13081-970 Campinas, SP (Brazil); Casado, Juan [Departamento de Química-Física, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga (Spain); Rodríguez-Castellón, Enrique, E-mail: castellon@uma.es [Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga (Spain)

2017-01-01

Chitosan is a biopolymer with potential applications in various fields. Recently, it has been used for heavy metals removal like copper, due to the presence of amino and hydroxyl groups in its structure. Chitosan membranes were crosslinked with epichlorohydrin and bisoxirano and functionalized with chelating agents, such as iminodiacetic acid, aspartic acid and tris-(2-amino-ethyl) polyamine. These membranes were used for copper adsorption and the formed complexes were characterized. Thermal and crystalline properties of chitosan membranes were studied by TG-DCS and X-ray diffraction. Raman, XPS and FT-IR data confirmed that copper is linked to the modified chitosan membranes by the amino groups. The oxidation state of copper-chitosan membranes were also studied by angle resolved XPS, and by UV–Vis diffuse reflectance spectroscopy. - Highlights: • Chitosan membranes were crosslinked with epichlorohydrin and bisoxirano and functionalized with chelating agents. • The chelating agent were iminodiacetic acid, aspartic acid and tris-(2-amino-ethyl) polyamine. • The functionalized membranes were used for copper adsorption and studied by ARXPS, Raman, TG-DCS, FT-IR and XRD. • Spectroscopic data confirmed that copper is linked to the modified chitosan membranes by the amino groups.

Combined DFT and XPS investigation of iodine anions adsorption on the sulfur terminated (001) chalcopyrite surface

Energy Technology Data Exchange (ETDEWEB)

Li, Kui, E-mail: likui9606@stu.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Zhao, Yaolin, E-mail: zhaoyaolin@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Zhang, Peng, E-mail: zp32@qq.com [Sino Shaanxi Nuclear Industry Group, Xi’an 710100 (China); He, Chaohui, E-mail: hechaohui@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Deng, Jia, E-mail: djkokocase@stu.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Ding, Shujiang, E-mail: dingsj@mail.xjtu.edu.cn [Department of Applied Chemistry, School of Science, Xi’an Jiaotong University, Xi’an 710049 (China); Shi, Weiqun, E-mail: shiwq@ihep.ac.cn [Key Laboratory of Nuclear Radiation and Nuclear Energy Technology and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

2016-12-30

Highlights: • Metal surface sites of (001)-S surface of chalcopyrite show significant chemical affinity to iodide and iodate. • The energetically favorable active site is copper for iodide adsorption and iron for iodate adsorption, respectively. • Iodate undergoes a dissociative adsorption on the copper site of chalcopyrite surface. - Abstract: The adsorption of iodine anions (iodide and iodate) on the sulfur terminated (001) chalcopyrite surface has been systematically investigated combining first-principles calculations based on density functional theory (DFT) with X-ray photoelectron spectroscopy (XPS) measurements. Based on the total energy calculations and geometric optimization, the thermodynamically preferred site was copper atom for iodide adsorption and iron atom for iodate adsorption, respectively. In the case of Cu site mode, the iodate underwent a dissociative adsorption, where one I−O bond of iodate ion was broken and the dissociative oxygen atom adsorbed on the adjacent sulphur site. Projected density of states (PDOS) analysis further clarified the interaction mechanism between active sites of chalcopyrite surface and adsorbates. In addition, full-range XPS spectra qualitatively revealed the presence of iodine on chalcopyrite surface. High resolution XPS spectra of the I 3d peaks after adsorption verified the chemical environment of iodine. The binding energies of 618.8 eV and 623.5 eV for I 3d{sub 5/2} peaks unveiled that the adsorption of iodide and iodate ions on copper-iron sulfide minerals was the result of formation of low solubility metal iodides precipitate. Also two I 3d peaks with low intensity around 618 eV and 630 eV might be related to the inorganic reduction of iodate to iodide by reducing S{sup 2−} ion of chalcopyrite.

Resistencia a la corrosión y desgaste de recubrinnientos deTiN obtenidos por PVD

Directory of Open Access Journals (Sweden)

Conde, A.

2005-12-01

Full Text Available Surface hardening techniques for metallic alloys are widely used to achieve layers of very high hardness and corrosion and wear resistance. In the present paper TiN coatings are obtained by PVD on a tool steel. The films are characterized by SEM, X-ray diffraction and XPS. Corrosion behaviour in NaCl solution showed the importance of the presence of defects on the PVD coating due to the different electrochemical behaviour of the steel base. Pin-on-disk measurements at approximately 40% RH against a corundum (Al₂O₃ ball showed a significant decrease in the wear rate compared with the results for the standard tool steel.

Los tratamientos de endurecimiento superficial de aleaciones metálicas se utilizan para lograr capas de muy elevada dureza, resistencia a la corrosión y desgaste. En este trabajo, se estudia el comportamiento de recubrimientos de TiN obtenidos mediante PVD sobre aceros de herramientas. Las capas obtenidas se caracterizan mediante microscopía electrónica de barrido, difracción de rayos X y XPS. Se analiza el comportamiento frente a la corrosión de las capas protectoras, así como la influencia del substrato en su comportamiento en soluciones de NaCl. Finalmente, se realizan ensayos de desgaste por deslizamiento en seco mediante la técnica de pin-on-disk, comprobándose la mayor resistencia de estas capas.

ÍNDICE DE SUSTENTABILIDADE AMBIENTAL NO MUNICÍPIO DE ARUANÃ, GOIÁS, CALCULADO COM BASE NO MÉTODO DASHBOARD OF SUSTAINABILITY: UMA ANÁLISE MULTIDISCIPLINAR VOLTADA À PROMOÇÃO DO DESENVOLVIMENTO SUSTENTÁVEL.

OpenAIRE

Barbosa, Camilla Di Ribeiro

2014-01-01

O Município de Aruanã em Goiás é referência não só regional, como também nacional quando se pensa em turismo de pesca. Por esta característica, foi analisado o grau de desenvolvimento sustentável do município de Aruanã, através do método do Painel de Sustentabilidade (DashboardofSustainability), que se caracteriza por abordar quatro dimensões, ambiental, econômica, social e institucional. Foram analisados 3 indicadores para a dimensão ambiental, 5 indicadores para a dimensão...

A XPS Study of the Passivity of Stainless Steels Influenced by Sulfate-Reducing Bacteria.

Science.gov (United States)

Chen, Guocun

The influence of sulfate-reducing bacteria (SRB) on the passivity of type 304 and 317L stainless steels (SS) was investigated by x-ray photoelectron spectroscopy (XPS), microbiological and electrochemical techniques. Samples were exposed to SRB, and then the resultant surfaces were analyzed by XPS, and the corrosion resistance by potentiodynamic polarization in deaerated 0.1 M HCl. To further understand their passivity, the SRB-exposed samples were analyzed by XPS after potentiostatic polarization at a passive potential in the hydrochloric solution. The characterization was performed under two surface conditions: unrinsed and rinsed by deaerated alcohol and deionized water. Comparisons were made with control samples immersed in uninoculated medium. SRB caused a severe loss of the passivity of 304 SS through sulfide formation and possible additional activation to form hexavalent chromium. The sulfides included FeS, FeS_2, Cr_2S _3, NiS and possibly Fe_ {rm 1-x}S. The interaction took place nonuniformly, resulting in undercutting of the passive film and preferential hydration of inner surface layers. The bacterial activation of the Cr^{6+ }^ecies was magnified by subsequent potentiostatic polarization. In contrast, 317L SS exhibited a limited passivity. The sulfides were formed mainly in the outer layers. Although Cr^{6+}^ecies were observed after the exposure, they were dissolved upon polarization. Since 317L SS has a higher Mo content, its higher passivity was ascribed to Mo existing as molybdate on the surface and Mo^{5+} species in the biofilm. Consequently, the interaction of SRB with Mo was studied. It was observed that molybdate could be retained on the surfaces of Mo coupons by corrosion products. In the presence of SRB, however, a considerable portion of the molybdate interacted with intermediate sulfur -containing proteins, forming Mo(V)-S complexes and reducing bacterial growth and sulfate reduction. The limited insolubility of the Mo(V)-S complexes in 0

XNAES and XPS studies on modification of SWCNTS upon gas-phase purification treatments

International Nuclear Information System (INIS)

Liang Xianqing; Wu Ziyu; Zhong Jun; Zhao Ting; Yao Peng; Ibrahim, K.; Qian Haijie

2009-01-01

A systematic characterization of single-walled carbon nanotubes (SWCNTs) after successive purification steps, including air oxidation at 350 degree C, hydrochloric acid etching and 600 degree C annealing in Ar, have been performed combining X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy (XPS). The results indicated that the modification degree of SWCNTs increased after the purification procedures, but decreased significantly by annealing in Ar. It also showed that the SWCNTs could bond with chlorine atoms during the hydrochloric acid etching and suggested this modification may be importance for the applications. (authors)

Mediastinite por perfuração e ruptura do esôfago torácico

Directory of Open Access Journals (Sweden)

Geraldo Roger Normando Jr.

Full Text Available OBJETIVO: Avaliar a mortalidade por mediastinite e sepse originadas por perfuração e ruptura do esôfago torácico, de acordo o tempo de evolução da doença. MÉTODO: Estudo retrospectivo de 14 anos (1992 a 2006, com pacientes portadores de ruptura e perfuração do esôfago. Foi avaliado sexo, idade, mecanismo de lesão, evolução ( 24 horas e tratamento. RESULTADOS: Foram analisados 44 pacientes, sendo 10 do sexo feminino (22,73% e 34 do sexo masculino (77,27%. A variação da idade foi de dois meses a 77 anos e a média de 33,2. Os ferimentos estiveram presentes em 19 casos (43,18%: Arma branca em cinco e projétil de arma de fogo 14. A instrumentação endoscópica foi detectada em nove casos (20,45%. Nos pacientes submetidos à esofagorrafia (diagnóstico precoce, menos de 24 horas a mortalidade esteve presente três casos (20%. Em pacientes submetidos à esofagectomia (diagnóstico tardio, mais de 24 horas a mortalidade ocorreu em oito casos (36,36%, e essa diferença não foi estatisticamente significante (p 0,05. No tratamento conservador, a mortalidade foi em cinco de sete casos a a diferença foi estatisticamente significativa quando comparado com o tratamento cirúrgico. CONCLUSÕES: O tratamento conservador para mediastinite por ruptura e perfuração do esôfago mostrou mortalidade alta quando comparada com tratamento cirúrgico. Entre os pacientes operados, a diferença não foi estatisticamente significante, confirmando a indicação de esofagectomia para casos de infecção avançada e a esofagorrafia para casos precoces.

Práticas não convencionais em saúde por familiares e vínculos afetivos de pacientes críticos Unconventional health practices by family and affective bonds of critic patients

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Jocelly de Araújo Ferreira

2017-01-01

Full Text Available Objetivo: averiguar a aplicabilidade das práticas não convencionais na saúde de visitantes com vínculos afetivos e/ou familiares de pacientes críticos. Métodos: Estudo descritivo, quantitativo, realizado nos ambientes de atendimento ao paciente crítico do Hospital Estadual de Emergência e Trauma, na cidade de João Pessoa – Paraíba. A amostra foi composta por 100 familiares. Os dados foram coletados por meio de entrevista semiestruturada e analisados pelo Software Statistical Package for Social Sciences. Aprovado pelo Comitê de Ética em Pesquisa, sob o número 328.320.  Resultados: Observou-se aplicabilidade, conhecimento e boa aceitação na utilização de algumas práticas não convencionais, por familiares e por vínculos afetivos de pacientes críticos. Conclusão: As práticas não convencionais proporcionam um cuidado integral ao indivíduo, aos familiares e vínculos afetivos. Os familiares e vínculos afetivos transmitem uma grande confiabilidade destas práticas, reconhecendo-as e integrando-as como componente fundamental para a influência do seu uso. Descritores: Terapias complementares, Cuidados críticos, Ações terapêuticas.

Dificuldade sexual vivenciada por mulheres em crise de HIV-1 La dificultad sexual vivida por mujeres en crisis de HIV-1 Sexual problems experienced by women in an HIV-1 crisis

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Mara Rúbia Ignácio de Freitas

2000-07-01

Full Text Available Esta pesquisa de caráter descritivo insere-se nos pressupostos dos métodos qualitativos de investigação, sendo fundamentada pela Teoria da Crise preconizada por CAPLAN (1966. Teve como objetivo identificar as dificuldades sexuais vivenciadas por mulheres em crise de HIV-1. Os dados foram coletados através de entrevista semi-estruturada, gravada segundo FREITAS et al. (1992 e analisados segundo MEIHY (1996. Concluímos que as mulheres mantiveram o desequilíbrio, apresentando mecanismos de enfrentamento negativo. Acreditamos que é possível ajudá-las através de ações de enfermagem adequadas tais como atividades educativas, de orientação mas principalmente aquelas dirigidas para atender as necessidades apresentadas pela pessoa em crise de HIV-1.Esta investigación de carácter descriptivo se inserta en los presupuestos de los métodos cualitativos de investigación, y se base en la teoría de la crisis defendida por CAPLAN (1966. Tuvo como objetivo identificar las dificultades sexuales vividas por las mujeres en crisis de HIV-1. Los datos fueron recolectados a través de una entrevista semi-estructurada, grabada según FREITAS et. al. (1992 y analizados según MEIHY (1996. Concluimos que las mujeres mantuvieron el desequilibrio, presentando mecanismos de enfrentamiento negativo. Creemos que es posible ayudarlas a través de acciones de enfermería adecuadas tales como actividades educativas, de orientación y principalmente aquellas dirigidas para la atención de las necesidades presentadas por la persona en crisis de HIV-1.This descriptive study was based on the assumptions of qualitative investigation methods and on the Crisis Theory formulated by CAPLAN (1966. The objective of the study was to identify the sexual problems experienced by women undergoing an HIV-1 crisis. Data were collected through a semi-structured interview recorded by the method of FREITAS et al. (1992 and analyzed by the method of MEIHY (1996. Authors concluded

AVALIAÇÃO DA ATIVIDADE ANTIOXIDANTE IN VITRO DOS CHÁS MATE E VERDE ANTES E APÓS A BIOTRANSFORMAÇÃO POR LIPASES

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Camila Morais Gonçalves da SILVA

2012-12-01

Full Text Available Os chás mate e verde, comuns na dieta brasileira, foram avaliados primeiramente quanto a sua composição: os polifenóis totais e os flavonóides totais das matrizes alimentares in natura foram quantificados por espectrofotometria, enquanto o perfil de composição foi analisado por espectrometria de massas (ESI-MS. Posteriormente, a atividade antioxidante foi avaliada por ensaios in vitro, antes e após a biotransformação enzimática por lipase de pâncreas de porco e lipase de Aspergillus niger comerciais, nas condições de reação estabelecidas pelo fabricante. Amostras dessas matrizes foram avaliadas por diferentes métodos: FRAP, DPPH, co-oxidação β-caroteno/ ácido linoléico, ORAC e a peroxidação lipídica foi avaliada pelo índice de TBARS. Subsequentemente foi realizada uma comparação entre o potencial antioxidante dos chás in natura, sem biotransformação, com os chás liofilizados também não biotransformados, a fim de avaliar se o processo de liofilização poderia comprometer a capacidade antioxidante da amostra, já que este poderia ser utilizado como método de conservação das amostras para futuros testes. A biotransformação enzimática aumentou a atividade antioxidante de ambos os chás, enquanto o processo de liofilização não promoveu alterações no potencial antioxidante das matrizes estudadas, quando comparadas as amostras in natura.

Reduction of mixed Mn-Zr oxides: in situ XPS and XRD studies.

Science.gov (United States)

Bulavchenko, O A; Vinokurov, Z S; Afonasenko, T N; Tsyrul'nikov, P G; Tsybulya, S V; Saraev, A A; Kaichev, V V

2015-09-21

A series of mixed Mn-Zr oxides with different molar ratios Mn/Zr (0.1-9) have been prepared by coprecipitation of manganese and zirconium nitrates and characterized by X-ray diffraction (XRD) and BET methods. It has been found that at concentrations of Mn below 30 at%, the samples are single-phase solid solutions (MnxZr1-xO2-δ) based on a ZrO2 structure. X-ray photoelectron spectroscopy (XPS) measurements showed that manganese in these solutions exists mainly in the Mn(4+) state on the surface. An increase in Mn content mostly leads to an increase in the number of Mn cations in the structure of solid solutions; however, a part of the manganese cations form Mn2O3 and Mn3O4 in the crystalline and amorphous states. The reduction of these oxides with hydrogen was studied by a temperature-programmed reduction technique, in situ XRD, and near ambient pressure XPS in the temperature range from 100 to 650 °C. It was shown that the reduction of the solid solutions MnxZr1-xO2-δ proceeds via two stages. During the first stage, at temperatures between 100 and 500 °C, the Mn cations incorporated into the solid solutions MnxZr1-xO2-δ undergo partial reduction. During the second stage, at temperatures between 500 and 700 °C, Mn cations segregate on the surface of the solid solution. In the samples with more than 30 at% Mn, the reduction of manganese oxides was observed: Mn2O3 → Mn3O4 → MnO.

An XPS round robin investigation on analysis of wood pulp fibres and filter paper

Science.gov (United States)

Johansson, Leena-Sisko; Campbell, J. M.; Fardim, Pedro; Hultén, Anette Heijnesson; Boisvert, Jean-Philippe; Ernstsson, Marie

2005-06-01

X-ray photoelectron spectroscopy (XPS) has been applied to pulp and paper research for decades. However, there has been no attempt to standardise or even systematically compare experimental and analysis procedures, even though it is known that fibrous, nature-derived and insulating fibre materials pose remarkable challenges to reliable surface analysis. The experimental problems are mainly linked with neutralisation, energy resolution, contamination and X-ray induced degradation. We have tested applicability, reliability and reproducibility of XPS analysis on real pulp samples with varying lignin and extractives contents in a small round robin investigation. We also tested the instrumental set-ups with an acetone-extracted filter paper, used as a reference sample. The data, collected at four different laboratories with state-of-the-art instruments indicate that reproducible results can be obtained, despite minor differences in experimental and analysis procedures. However, we found that a specified sample handling procedure and limited X-ray exposure are crucial for reproducible, reliable data. Based on the round robin data we recommend dose restricted monochromatic measurements, a cellulosic in situ reference and a consistent sample handling procedure. The data confirms that a paper-based reference material and the correlation of high-resolution C 1s data with O/C atomic ratios can be used in testing instruments and experimental set-ups for pulp and paper materials.

Rotary friction welding of dissimilar joints and bonding interface characterization by EDX and XPS

Energy Technology Data Exchange (ETDEWEB)

Alves, Eder Paduan; Dollinger, Christian Avila [Instituto de Aeronautica e Espaco (IAE), Sao Jose dos Campos, SP (Brazil); Marcuzzo, Jossano Saldanha; Baldan, Mauricio Ribeiro; Toledo, Rafael Cardoso; Piorino Neto, Francisco; An, Chen Ying, E-mail: eder.padua@yahoo.com.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)

2016-07-01

Full text: Welding of dissimilar materials has been a challenge to engineering. The study and development of new union processes that meet the requirements of projects in the aerospace, nuclear and aviation sector are of great importance to the scientific and productive means. The Rotary friction welding process (RFW) is a process of union that occurs in the solid state, without occurrence of fusion between the parties, and that have like the main bonding mechanisms the diffusion and mechanical mixture. This work has as objective the obtaining of dissimilar joints involving AA 6351-T6 alloy and stainless steel AISI 304l for applications in the aerospace area. The joints obtained by RFW who had procedures and qualified welding process have undergone the techniques of Energy Dispersive X-Ray Spectroscopy (EDX) and X-Ray Photoelectron Spectroscopy (XPS) for analysis of the bonding interface. Were obtained joints with superior mechanical properties the AA 6351-T6 alloy, with the fracture occurring in aluminum away from the bonding interface. The analyses carried out by EDX and XPS have shown the occurrence of interdiffusion among the main elements of the materials involved. The Rotary friction welding process proved to be a great method for obtaining of joints between dissimilar materials that are not possible by fusion welding processes. (author)

Rotary friction welding of dissimilar joints and bonding interface characterization by EDX and XPS

International Nuclear Information System (INIS)

Alves, Eder Paduan; Dollinger, Christian Avila; Marcuzzo, Jossano Saldanha; Baldan, Mauricio Ribeiro; Toledo, Rafael Cardoso; Piorino Neto, Francisco; An, Chen Ying

2016-01-01

Full text: Welding of dissimilar materials has been a challenge to engineering. The study and development of new union processes that meet the requirements of projects in the aerospace, nuclear and aviation sector are of great importance to the scientific and productive means. The Rotary friction welding process (RFW) is a process of union that occurs in the solid state, without occurrence of fusion between the parties, and that have like the main bonding mechanisms the diffusion and mechanical mixture. This work has as objective the obtaining of dissimilar joints involving AA 6351-T6 alloy and stainless steel AISI 304l for applications in the aerospace area. The joints obtained by RFW who had procedures and qualified welding process have undergone the techniques of Energy Dispersive X-Ray Spectroscopy (EDX) and X-Ray Photoelectron Spectroscopy (XPS) for analysis of the bonding interface. Were obtained joints with superior mechanical properties the AA 6351-T6 alloy, with the fracture occurring in aluminum away from the bonding interface. The analyses carried out by EDX and XPS have shown the occurrence of interdiffusion among the main elements of the materials involved. The Rotary friction welding process proved to be a great method for obtaining of joints between dissimilar materials that are not possible by fusion welding processes. (author)

A comparative study of Mg and Pt contacts on semi-insulating GaAs: electrical and XPS characterization

Czech Academy of Sciences Publication Activity Database

Dubecký, F.; Kindl, Dobroslav; Hubík, Pavel; Mičušík, M.; Dubecký, M.; Boháček, P.; Vanko, G.; Gombia, E.; Nečas, V.; Mudroň, J.

2017-01-01

Roč. 395, Feb (2017), s. 131-135 ISSN 0169-4332 Institutional support: RVO:68378271 Keywords : semi-insulating GaAs * metal -semiconductor contact * interface * work function * electron transport * XPS Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.387, year: 2016

Antibiótico antifungico produzido por um estreptomiceto da região de Araraquara

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K. Ujikawa

2009-01-01

Full Text Available

Com o aumento significativo na incidência de infecções fúngicas invasivas durante a última década, principalmente em pacientes com câncer, AIDS, ou hospitalizados por período prolongado em unidades de terapia intensiva, há a necessidade da pesquisa de novos agentes antifúngicos com qualidade superior aos existentes. Esta pesquisa objetivou a procura de um microrganismo produtor de substâncias antibacterianas e antifúngicas. Microrganismos das amostras de solo da região de Araraquara, Brasil, foram coletados e analisados quanto ao seu potencial antimicrobiano contra microrganismos padrões (Staphylococcus aureus, Escherichia coli, Candida albicans, Aspergillus oryzae. Das 64 cepas isoladas, 34 apresentaram atividade antimicrobiana. A cepa Ar 4014 foi escolhida para dar continuidade ao trabalho por apresentar boa atividade antimicrobiana contra Candida albicans. Estudos fermentativos mostraram que os Meios 608-K e 602- B foram os melhores para produção e extração de substâncias antifúngicas de Ar 4014. Após cromatografia em coluna de sílica do extrato bruto, as frações ativas obtidas mostraram picos de absorção UV-VIS característicos de pentaenos normais. O antibiótico foi denominado provisoriamente Ara 4014-75. Palavras-chave: Antibiótico Ara 4014-75, Streptomyces, pentaenos, antifúngico, rastreamento.

An XPS [x-ray photoelectron spectroscopy] study of the sulfidation-regeneration cycle of a hydroprocessing catalyst

Energy Technology Data Exchange (ETDEWEB)

Shang, D.Y.; Adnot, A.; Kaliaguine, S. (Laval Univ., Ste-Foy, PQ (Canada)); Chmielowiec, J. (Petro Canada Products Co., Mississauga, ON (Canada))

1993-10-01

The formation of sulfates in an industrial Ni-W hydroprocessing (HP) catalyst was investigated by x-ray photoelectron spectroscopy (XPS). A small fluidized bed test unit with on-line sampling device was constructed to simulate industrial sulfidation and oxyregeneration processes of HP catalysts. The results obtained show that the sulfates observed on the surface of sulfided catalysts are not formed during the sulfidation process. Two oxidation processes seem to be responsible for the formation of sulfates: one happens when the catalyst is exposed to air before it is properly cooled and the other is a slow conversion at ambient temperature. The two different processes might be associated to different sulfidic species formed during the sulfidation processes, with the sulfides in the bulk of catalyst particles being more easily oxidized than the ones on the external surface of the catalyst particles. The sulfate formed during the air oxidation of sulfided catalysts, as well as that after oxyregeneration, is not aluminum sulfate but nickel sulfate in both cases. XPS results also indicate that oxygenates in the feedstock are not directly involved in the sulfate formation. 18 refs., 9 figs., 6 tabs.

XPS/NEXAFS spectroscopic and conductance studies of glycine on AlGaN/GaN transistor devices

Science.gov (United States)

Myers, Matthew; Khir, Farah Liyana Muhammad; Home, Michael A.; Mennell, Christopher; Gillbanks, Jeremy; Tadich, Anton; Baker, Murray V.; Nener, Brett D.; Parish, Giacinta

2018-03-01

We report on a study using a combination of XPS/NEXAFS and conductivity measurements to develop a fundamental understanding of how dipolar molecules interact with the heterostructure device surface and affect the device conductivity of AlGaN/GaN heterostructure-based transistors. In such structures, which are increasingly being investigated for chemical and biological sensing, a 2-dimensional electron gas spontaneously forms at the layer interface that is sensitive to the charge characteristics of the exposed surface. Glycine, chosen for this study because it is the simplest of the amino acids and is known to form a zwitterionic configuration when stabilized through intermolecular interactions, was evaporated under ultra-high vacuum conditions onto the device surface and subsequently both XPS/NEXAFS and conductivity measurements were conducted. NEXAFS spectra show a preferential orientation for the Glycine molecules on the surface and evidence for both neutral and zwitterionic species on the surface. In situ conductivity measurements suggest that the negatively charged carboxylate group is closest to the surface. These results are a unique and pivotal contribution to the previous and at times conflicting literature on the zwitterionic nature of Glycine.

XPS study of U, UNi5, UCu5 and UNisub(0.5)Cusub(4.5)

International Nuclear Information System (INIS)

Grohs, H.; Hoechst, H.; Steiner, P.; Huefner, S.; Buschow, K.H.J.

1980-01-01

Core and valence band spectra of U metal and the intermetallic compounds UNi 5 , UCu 5 and UNisub(0.5)Cusub(4.5) have been measured by X-ray excited photoelectron spectroscopy (XPS). The data indicate that in UNi 5 the configuration is 5f 3 , and in UCu 5 and UNisub(0.5)Cusub(4.5) a mixed valence configuration with fewer 5f electrons than in UNi 5 is present. (author)

Sorteio de domicílios em favelas em inquéritos por amostragem

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Maria Cecilia Goi Porto Alves

2011-12-01

Full Text Available OBJETIVO: Identificar vantagens e desvantagens do uso de segmentos em relação ao sorteio feito a partir da lista completa de endereços, para o sorteio de domicílios em amostragem por conglomerados em múltiplos estágios em favelas. PROCEDIMENTOS METODOLÓGICOS: Estudo qualitativo realizado em quatro favelas sorteadas no Inquérito de Saúde do Município de São Paulo, SP, 2008, nas quais foram aplicadas as duas técnicas. Foram realizados grupos focais com pesquisadores de campo - "arroladores" e entrevistadores do inquérito. Os conteúdos das conversações foram analisados, agrupados em categorias e organizados em núcleos temáticos. ANÁLISE DOS RESULTADOS: A utilização de segmentos de domicílios foi associada a numerosas vantagens e poucas desvantagens. Entre as vantagens, constaram a rapidez e facilidade na elaboração do cadastro de endereços e na localização e identificação de domicílios na etapa de realização das entrevistas, maior segurança dos entrevistadores e da população, maior acesso aos entrevistados, maior estabilidade e maior cobertura do cadastro produzido, e menor ocorrência de erros na identificação dos domicílios sorteados. CONCLUSÕES: A construção de cadastro de domicílios por meio da criação de segmentos é vantajosa em relação à listagem completa de endereços, quando feita em favelas. Por ter se mostrado uma opção econômica e fácil de ser aplicada, constitui alternativa para a simplificação do processo de amostragem em áreas com as suas características de desorganização e adensamento de domicílios.

Study by X-ray photoelectron spectroscopy (XPS) and radiochemistry (Cl36) of the interaction of chloride ions with a passive film formed on nickel

International Nuclear Information System (INIS)

Herbelin, Jean-Marc

1990-01-01

This research thesis reports the study of the influence of chlorides on nickel passivation by using a radiochemical method based on the use of the Cl 36 isotope and the X-ray photoelectron spectroscopy (XPS). The first one allows the in-situ determination of the adsorption of chlorides on the surface, or their inclusion in surface films during the electrochemical treatment. The XPS analysis allows the characterization of modifications induced by chlorides in passive films. The obtained results allow a better understanding in the interpretation of the mechanisms of corrosion induced by chloride ions [fr

Surface refinement and electronic properties of graphene layers grown on copper substrate: An XPS, UPS and EELS study

Czech Academy of Sciences Publication Activity Database

Siokou, A.; Ravani, F.; Karakalos, S.; Frank, Otakar; Kalbáč, Martin; Galiotis, C.

2011-01-01

Roč. 257, č. 23 (2011), s. 9785-9790 ISSN 0169-4332 R&D Projects: GA MŠk LC510; GA AV ČR IAA400400911 Institutional research plan: CEZ:AV0Z40400503 Keywords : graphene * XPS * EELS Subject RIV: CG - Electrochemistry Impact factor: 2.103, year: 2011

XPS and SIMS study of aluminium native oxide modifications induced by Q-switched Nd :YAG laser treatment

CSIR Research Space (South Africa)

Barnier, V

2006-04-01

Full Text Available with fluences between 0.7 and 1.7 J/cm2, X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) revealed thermal oxidation with an increase of the oxide-layer thickness for 0.7–1.3 J/cm2. Above a threshold at about 1.3 J/cm2 the oxide...

Reaproveitamento do concentrado gerado por sistema de tratamento de água por osmose reversa em uma clínica de hemodiálise

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Paulo Gil Siqueira de Faria

Full Text Available RESUMO: O principal tratamento à doença renal crônica no Brasil, segundo o Censo Brasileiro de Nefrologia de 2013, é a hemodiálise, para a qual é necessária a utilização de água purificada em acordo com a Agência Nacional de Vigilância Sanitária (ANVISA e com os padrões internacionais do FDA, Food and Drugs Adminstration e da Association for Advancement of Medicine Instrumentation (AAMI. Para atender aos parâmetros estabelecidos, utiliza-se processo de purificação por osmose reversa (OR, onde ocorre a separação do afluente, através da membrana semipermeável, restando de um lado a água purificada e do outro lado o concentrado. O presente estudo visa abordar a viabilidade qualitativa e quantitativa do reaproveitamento deste concentrado, através de estudo de caso em unidade de OR instalada em uma clínica de hemodiálise na cidade de Curitiba. Foi realizada a avaliação experimental, através de análises físico-químicas e microbiológicas do concentrado, buscando atender as quatro classes de reuso sugeridas pela ABNT NBR 13969/97. Também foram analisados os parâmetros amônia, cloreto, cloro residual livre, dureza e ferro totais, fluoreto, nitratos, nitritos, sulfatos, sólidos totais dissolvidos e coliformes totais e comparados com o padrão de potabilidade. O volume de concentrado foi medido através do uso de hidrômetros em pontos estratégicos. Observou-se que a clínica reaproveita cerca de 23% do concentrado. Os resultados obtidos atendem às quatro classes de reuso, porém deve-se observar o parâmetro fluoreto cujo valor mostrou-se igual ao limite imposto pela norma de água potável.

Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology

International Nuclear Information System (INIS)

Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

2016-01-01

Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH_3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH_3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. - Highlights: • Hazardous AMFR material was treated by slow pyrolysis reaction. • TG-FTIR-MS were used to study the N conversion for pyrolysis gas and bio-oil. • NH_3 and HCN were observed as the main N-containing gas species. • XPS were used to study the N conversion for pyrolysis char. • Stable species, such as N-oxide and quaternary-N, were

Effects of XPS operational parameters on investigated sample surfaces

International Nuclear Information System (INIS)

Mrad, O.; Ismail, I.

2013-04-01

In this work, we studied the effects of the operating conditions of the xray photoelectron spectroscopy analysis technique (XPS) on the investigated samples. Firstly, the performances of the whole system have been verified as well as the accuracy of the analysis. Afterwards, the problem of the analysis of insulating samples caused by the charge buildup on the surface has been studied. The use of low-energy electron beam (<100 eV) to compensate the surface charge has been applied. The effect of X-ray on the samples have been assessed and was found to be nondestructive within the analysis time. The effect of low- and high-energy electron beams on the sample surface have been investigated. Highenergy electrons were found to have destructive effect on organic samples. The sample heating procedure has been tested and its effect on the chemical stat of the surface was followed. Finally, the ion source was used to determine the elements distribution and the chemical stat of different depths of the sample. A method has been proposed to determine these depths (author).

Geochemistry of the Cigar Lake uranium deposit: XPS studies

International Nuclear Information System (INIS)

Sunder, S.; Cramer, J.J.; Miller, N.H.

1996-01-01

Samples of uranium ore from the Cigar Lake deposit in northern Saskatchewan, Canada, were analyzed using XPS. High-resolution spectra were recorded for the strongest bands of the major elements (U 4f, C 1 s, O 1 s, Pb 4 f, S 2 p, Cu 2 p, Fe 2 p, and the valence region (0-20 eV)) to obtain chemical state information for these samples. In general, the U VI /U IV ratio was very low, i.e., much less than 0.5, the threshold for the oxidative dissolution of UO 2 . The low values of the U VI /U IV ratio observed for samples from the Cigar Lake deposit indicate thermodynamic stability of the uranium ore in the reduced aqueous environment. Similarities between the disposal vault envisaged in the Canadian Nuclear Fuel Waste Management Program and the Cigar Lake deposit suggest that, if geochemical conditions in the vault were to be similar to those in the deposit, the long-term dissolution of UO 2 fuel would be very minimal. (orig.)

Surtos de intoxicação por salinomicina em chinchilas (Chinchilla lanigera

Directory of Open Access Journals (Sweden)

Ricardo B. Lucena

2012-01-01

Full Text Available Quatro surtos de intoxicação por salinomicina são descrito em chinchilas de três municípios do Estado do Rio Grande do Sul. Uma semana após a ingestão de ração contendo 37 ppm de salinomicina, aproximadamente duas mil chinchilas de quatro fazendas expostas diminuíram o consumo da ração. Quatrocentos e vinte sete chinchilas demonstraram apatia. Dessas, duzentos e setenta e sete desenvolveram decúbito esternal e lateral, dispneia e coma, seguidos de morte. As primeiras mortes ocorreram oito dias após a ingestão da ração. A evolução dos sinais clínicos até a morte ou eutanásia foi de 2-5 dias. Os exames bioquímicos do soro sanguíneo em quatro chinchilas revelaram níveis aumentados da alanina aminotransferase, aspartato transaminase, fosfatase alcalina, creatina cinase, glicose, triglicerídeos e colesterol total. Quarenta e cinco chinchilas foram submetidas à necropsia. Os achados macroscópicos consistiam de marcada lipidose hepática em todas as chinchilas necropsiadas; fetos em estado de decomposição em doze chinchilas que estavam prenhes. Microscopicamente, múltiplas fibras musculares esqueléticas estavam hipereosinofílicas, tumefeitas e com perda das estriações. Nas chinchilas que sobreviveram por mais dias era possível observar segmentos fragmentados de miofibras afetadas (necrose flocular e regeneração de miofibras. No fígado foi observada marcada degeneração gordurosa. Não foram observadas anormalidades microscópicas nos demais órgãos analisados. Análises à procura de aflatoxinas, resíduos de pesticidas e isolamento bacteriano foram negativos. A análise da ração por cromatografia líquida revelou 37ppm de salinomicina na ração. A ração suspeita foi administrada a 12 chinchilas, três das quais (25% morreram apresentando lesões semelhantes às observadas nas chinchilas com a doença natural. O diagnóstico de intoxicação por salinomicina foi baseado na epidemiologia, lesões histol

Electrochemical capacity fading of polyaniline electrode in supercapacitor: An XPS analysis

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Jinxing Deng

2017-04-01

Full Text Available To understand the electrochemical capacity fading of the polyaniline (PANI electrodes in supercapacitors, for the first time, their chemical structure change during electrochemical cycles was traced with XPS analysis after the HCl doped PANI electrodes were subjected to the cyclic voltammetry test in 1.0 M H2SO4 electrolyte for different cycle numbers. The results showed that the chlorine disappeared in the electrode surface, while the surface element contents of sulfur and oxygen increased with the electrochemical cycles increased. It demonstrated that the hydrolytic degradation of the PANI chains and exchange of dopant occurred during the electrochemical cycling, causing the fading in the mechanical and electrochemical performance of the PANI electrodes. This understanding should lead to better design of the conductive polymer-based energy storage devices.

XPS analysis of the carbon fibers surface modified via HMDSO to carbon nanotube growth

International Nuclear Information System (INIS)

Cardoso, L.D.R.; Gomes, M.C.B.; Trava-Airoldi, V.J.; Corat, E.J.; Lugo, D.C.

2016-01-01

Full text: Carbon fibers (CF) have been widely used to reinforce structural composites. Due to their strength-to-weight properties, CF composites are finding increased structural uses in areas such as aerospace, aeronautical, automobile and others. The strength of the fiber-resin interface bond has been found to be the limiting factor to the mechanical properties of CF-epoxy materials, due to their non-polar nature that limit the affinity of CF to bind chemically to any matrix. The growth of carbon nanotubes (CNTs) on the surface of CF is a promising approach for improving mechanical, electrical and thermal properties of structural composites. However growing CNTs on CF presents some obstacles, such as diffusion of metal catalyst particles on CF, uneven CNT growth and loss of mechanical properties of CF. To avoid the diffusion of catalyst particles we modified the CF surface with hexamethyldisiloxane (HMDSO) at low temperature (400 °C), also preventing the loss of mechanical properties and allowing uniform CNTs growth. We deposited CNTs via floating catalyst method, with ferrocene providing the catalyst particle and the oxidative dehydrogenation reaction of acetylene providing the carbon. The CF surface modification was analyzed via X-ray photoelectron spectroscopy (XPS) and CNTs growth via scanning electron microscopy with field emission gun. The XPS analysis showed that HMDSO promotes the binding of oxygen to carbon and silicon present on CF surface, the chemical modification of the surface of the CF enables the uniform growth of carbon nanotubes. (author)

XPS analysis of the carbon fibers surface modified via HMDSO to carbon nanotube growth

Energy Technology Data Exchange (ETDEWEB)

Cardoso, L.D.R.; Gomes, M.C.B.; Trava-Airoldi, V.J.; Corat, E.J.; Lugo, D.C. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)

2016-07-01

Full text: Carbon fibers (CF) have been widely used to reinforce structural composites. Due to their strength-to-weight properties, CF composites are finding increased structural uses in areas such as aerospace, aeronautical, automobile and others. The strength of the fiber-resin interface bond has been found to be the limiting factor to the mechanical properties of CF-epoxy materials, due to their non-polar nature that limit the affinity of CF to bind chemically to any matrix. The growth of carbon nanotubes (CNTs) on the surface of CF is a promising approach for improving mechanical, electrical and thermal properties of structural composites. However growing CNTs on CF presents some obstacles, such as diffusion of metal catalyst particles on CF, uneven CNT growth and loss of mechanical properties of CF. To avoid the diffusion of catalyst particles we modified the CF surface with hexamethyldisiloxane (HMDSO) at low temperature (400 °C), also preventing the loss of mechanical properties and allowing uniform CNTs growth. We deposited CNTs via floating catalyst method, with ferrocene providing the catalyst particle and the oxidative dehydrogenation reaction of acetylene providing the carbon. The CF surface modification was analyzed via X-ray photoelectron spectroscopy (XPS) and CNTs growth via scanning electron microscopy with field emission gun. The XPS analysis showed that HMDSO promotes the binding of oxygen to carbon and silicon present on CF surface, the chemical modification of the surface of the CF enables the uniform growth of carbon nanotubes. (author)

Colloidal diatomite, radionickel, and humic substance interaction: a combined batch, XPS, and EXAFS investigation.

Science.gov (United States)

Sheng, Guodong; Shen, Runpu; Dong, Huaping; Li, Yimin

2013-06-01

This work determined the influence of humic acid (HA) and fulvic acid (FA) on the interaction mechanism and microstructure of Ni(II) onto diatomite by using batch experiments, X-ray photoelectron spectroscopy (XPS), and extended X-ray absorption fine structure (EXAFS) methods. Macroscopic and spectroscopic experiments have been combined to see the evolution of the interaction mechanism and microstructure of Ni(II) in the presence of HA/FA as compared with that in the absence of HA/FA. The results indicated that the interaction of Ni(II) with diatomite presents the expected solution pH edge at 7.0, which is modified by addition of HA/FA. In the presence of HA/FA, the interaction of Ni(II) with diatomite increased below solution pH 7.0, while Ni(II) interaction decreased above solution pH 7.0. XPS analysis suggested that the enrichment of Ni(II) onto diatomite may be due to the formation of (≡SO)2Ni. EXAFS results showed that binary surface complexes and ternary surface complexes of Ni(II) can be simultaneously formed in the presence of HA/FA, whereas only binary surface complexes of Ni(II) are formed in the absence of HA/FA, which contribute to the enhanced Ni(II) uptake at low pH values. The results observed in this work are important for the evaluation of Ni(II) and related radionuclide physicochemical behavior in the natural soil and water environment.

Combined application of XANES and XPS to study oxygen species adsorbed on Ag foil

CERN Document Server

Bukhtiyarov, V I; Kaichev, V V; Knop-Gericke, A; Mayer, R W; Schloegl, R

2001-01-01

Adsorbed oxygen species realized in the course of ethylene epoxidation over polycrystalline silver have been characterized by X-ray absorption near the edge structure and X-ray photoelectron spectroscopy. Namely, the combined application of XANES and XPS in similar UHV conditions using the same sample allowed us to assign an XAS feature to the nucleophilic and electrophilic oxygen. This is of great significance, since these species are suggested to be included into the active center for ethylene epoxidation. The differences in the oxygen-silver bonding of these oxygen species are discussed.

Atomic and nuclear analytical methods. XRF, Moessbauer, XPS, NAA and ion-beam spectroscopic techniques

International Nuclear Information System (INIS)

Verma, H.R.

2007-01-01

This book is a blend of analytical methods based on the phenomenon of atomic and nuclear physics. It comprises comprehensive presentations about X-ray Fluorescence (XRF), Moessbauer Spectroscopy (MS), X-ray Photoelectron Spectroscopy (XPS), Neutron- Activation Analysis (NAA), Particle Induced X-ray Emission Analysis (PIXE), Rutherford Backscattering Analysis (RBS), Elastic Recoil Detection (ERD), Nuclear Reaction Analysis (NRA), Particle Induced Gamma-ray Emission Analysis (PIGE), and Accelerator Mass Spectrometry (AMS). These techniques are commonly applied in the fields of medicine, biology, environmental studies, archaeology or geology et al. and pursued in major international research laboratories. (orig.)

Mulheres em situação de violência pelo parceiro íntimo: tomada de decisão por apoio institucional especializado

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Leônidas de Albuquerque Netto

Full Text Available RESUMO Objetivo Propõe-se analisar fatores envolvidos na tomada de decisão de mulheres em situação de violência interpessoal, praticada pelo parceiro íntimo, na busca por apoio institucional de referência. Métodos Pesquisa qualitativa, descritiva e exploratória. Dezesseis mulheres foram entrevistadas, entre junho e setembro de 2012, em um Centro de Referência à Mulher de Duque de Caxias, Rio de Janeiro, Brasil, por meio de instrumento semiestruturado e individual. Os relatos foram analisados pelo método do Discurso do Sujeito Coletivo. Resultados As mulheres buscaram suporte psicossocial quando a violência interpessoal alcançou o limite da tolerância. Este suporte possibilitou o resgate da autoestima e da confiança, além da tomada de consciência para a necessidade de mudança de vida e de autonomia econômica. Conclusões As mulheres alcançaram sua autoconfiança com a superação da violência, o que possibilitou o resgate da autoestima e a tomada de decisão para a saída da situação de violência interpessoal praticada pelo parceiro íntimo.

Motivações e Ações Sustentáveis Implementadas por Empreendedores do Setor Hoteleiro

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Maralysa Correia de Souza Cavalcanti

2015-06-01

Full Text Available O empreendedorismo segue um novo curso, no qual as empresas modificam seus processos produtivos, produtos e serviços, minimizando os impactos sociais e ambientais, utilizando mais eficientemente a energia e os recursos naturais. Tais ações iniciaram-se a partir da descoberta de oportunidades de mercado, as quais, além de gerar valor, preservam o ambiente, a sociedade e atendem as expectativas do público de interesse. O objetivo principal deste estudo é analisar as motivações e ações sustentáveis implementadas pelos empreendedores do setor hoteleiro em Aracaju, no Estado de Sergipe, considerando as dimensões da sustentabilidade econômica, ambiental e social. De natureza exploratória e descritiva, utiliza o método de estudo de casos múltiplos. Os dados foram coletados por meio de entrevistas semiestruturadas com empreendedores e também foram utilizadas evidências documentos e observação direta não participante. Foram escolhidos dois hotéis situados em Aracaju, por possuírem evidencias de atuação sustentável.  Os resultados mostraram que as motivações para abrir seus negócios confundem-se com as motivações para adotar e praticar ações sustentáveis. Nos casos analisados são desenvolvidas ações nas as dimensões econômica, social e ambiental, tendo como principal propósito a redução de custos e o alcance de vantagens competitivas.

Surface Propensity of Atmospherically Relevant Amino Acids Studied by XPS.

Science.gov (United States)

Mocellin, Alexandra; Gomes, Anderson Herbert de Abreu; Araújo, Oscar Cardoso; de Brito, Arnaldo Naves; Björneholm, Olle

2017-04-27

Amino acids constitute an important fraction of the water-soluble organic nitrogen (WSON) compounds in aerosols and are involved in many processes in the atmosphere. In this work, we applied X-ray photoelectron spectroscopy (XPS) to study aqueous solutions of four amino acids, glycine, alanine, valine, and methionine, in their zwitterionic forms. We found that amino acids with hydrophilic side chains and smaller size, GLY and ALA, tend to stay in the bulk of the liquid, while the hydrophobic and bigger amino acids, VAL and MET, are found to concentrate more on the surface. We found experimental evidence that the amino acids have preferential orientation relative to the surface, with the hydrophobic side chain being closer to the surface than the hydrophilic carboxylate group. The observed amino acid surface propensity has implications in atmospheric science as the surface interactions play a central role in cloud droplet formation, and they should be considered in climate models.

Influence of oxygen incorporation on the defect structure of GaN microrods and nanowires. An XPS and CL study

International Nuclear Information System (INIS)

Guzmán, G; Herrera, M; Silva, R; Vásquez, G C; Maestre, D

2016-01-01

We report a cathodoluminescence (CL) and x-ray photoelectron spectroscopy (XPS) study of the influence of oxygen incorporation on the defect structure of GaN microrods and nanowires. The micro- and nanostructures were synthesized by a thermal evaporation method, which enables us to incorporate oxygen at different concentrations by varying the growth temperature. HR-TEM measurements revealed that oxygen generates stacking fault defects and edge dislocations along the GaN nanowires. Amorphous GaO x N y compounds were segregated on the surface of the nanowires. XPS, XRD and CL measurements suggests that the microrods and nanowires were composed of amorphous oxynitride compounds at their surface and GaN at their inner region. CL measurements revealed that the nanostructures generated an emission of 2.68 eV that increased in intensity proportionally to their oxygen content. We have attributed this emission to electronic transitions between donor substitutional-oxygen (O N ) and acceptor interstitial-oxygen (O i ) state levels. (paper)

Mortalidade por armas de fogo no estado do Rio de Janeiro, Brasil: uma análise espacial

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Szwarcwald Célia Landman

1998-01-01

Full Text Available O aumento da mortalidade por armas de fogo no estado do Rio de Janeiro, Brasil, tem tomado um aspecto alarmante. O objetivo deste estudo foi caracterizar a evolução temporal da mortalidade por armas de fogo neste estado, no período de 1979 a 1992, conforme sexo, idade e região de residência (capital, cinturão metropolitano e interior do estado e estudar a propagação da epidemia ao longo do tempo e do espaço, com a utilização de técnicas de análise estatística espacial. No período analisado, a mortalidade por armas de fogo teve o seu maior crescimento entre adolescentes de 15 a 19 anos, do sexo masculino; estas taxas variaram de 13 a 16% para este grupo, conforme a região de residência. Para o grupo das crianças de 10 a 14 anos, a mortalidade por armas de fogo teve um acréscimo de 10% ao ano. Foi nítida a interiorização da mortalidade por armas de fogo. No início da série, observou-se uma direção preferencial de disseminação, ao longo dos municípios situados na costa leste do estado, acompanhando o trajeto de uma rodovia federal. Entre 1990 e 1992, entretanto, a difusão ocorreu em praticamente todas as direções. A constatação empírica da expansão generalizada da mortalidade por armas de fogo nega as afirmações corriqueiras de concentração da violência nos bolsões de pobreza das metrópoles brasileiras. Os programas para prevenir e controlar a epidemia devem abordar o problema sob diferentes aspectos, enfocando questões tanto no plano coletivo (proliferação de armas entre a população vinculada ao contrabando internacional de armas, aumento da criminalidade, expansão do tráfico de drogas e exclusão de oportunidades sociais, assim como no plano individual (relações e interações dos jovens com seu ambiente, em nível da família, da escola e da sociedade.

Modification of composite por -Si/SnOx power ion beam of nanosecond duration

International Nuclear Information System (INIS)

Korusenko, P.M.; Bolotov, V.V.; Knyazev, E.V.; Kovivchak, V.S.; Korepanov, A.A.; Nesov, S.N.; Povoroznyuk, S.N.

2011-01-01

The results of XPS (X-ray photoelectron spectroscopy), AES (Auger electron spectroscopy) and SEM (Scanning electron microscopy) investigation of tin oxide nanolayers on the samples of the composite por-Si/SnO x with different porosity of the matrix, formed under the influence of a powerful ion beam of nanosecond duration was presented. It is shown that fast melting and crystallization of the surface leads to the formation of globular structures with a typical size of 200 nm. Established that the tin is included in structure of the nanocomposite in the oxidized state with little inclusion of metallic β-tin. With increasing porosity, phase composition of nanolayers of tin is close to the state corresponding to the higher tin oxide SnO 2 . Also shows that with increasing porosity, the intensity of subvalent 4d lines of tin, which is apparently associated with an increased degree of hybridization of the tin atoms and oxygen atoms. According to the results stratified etching was to evaluate the changes of the elemental structure of the composite and the depth of penetration of tin. (authors)

Characterization of SiC in DLC/a-Si films prepared by pulsed filtered cathodic arc using Raman spectroscopy and XPS

International Nuclear Information System (INIS)

Srisang, C.; Asanithi, P.; Siangchaew, K.; Pokaipisit, A.; Limsuwan, P.

2012-01-01

DLC/a-Si films were deposited on germanium substrates. a-Si film was initially deposited as a seed layer on the substrate using DC magnetron sputtering. DLC film was then deposited on the a-Si layer via a pulsed filtered cathodic arc (PFCA) system. In situ ellipsometry was used to monitor the thicknesses of the growth films, allowing a precise control over the a-Si and DLC thicknesses of 6 and 9 nm, respectively. It was found that carbon atoms implanting on a-Si layer act not only as a carbon source for DLC formation, but also as a source for SiC formation. The Raman peak positions at 796 cm -1 and 972 cm -1 corresponded to the LO and TO phonon modes of SiC, respectively, were observed. The results were also confirmed using TEM, XPS binding energy and XPS depth profile analysis.

XPS, UV–vis spectroscopy and AFM studies on removal mechanisms of Si-face SiC wafer chemical mechanical polishing (CMP)

International Nuclear Information System (INIS)

Zhou, Yan; Pan, Guoshun; Shi, Xiaolei; Xu, Li; Zou, Chunli; Gong, Hua; Luo, Guihai

2014-01-01

Highlights: • CMP removal mechanism of Si-face SiC wafer is investigated through XPS analysis. • UV–vis spectroscopy is used to study CMP removal mechanisms. • CMP removal model of Si-face SiC wafer is proposed. • The variations of atomic step morphology on ultra-smooth surface via AFM is studied. - Abstract: Chemical mechanical polishing (CMP) removal mechanisms of on-axis Si-face SiC wafer have been investigated through X-ray photoelectron spectroscopy (XPS), UV–visible (UV–vis) spectroscopy and atomic force microscopy (AFM). XPS results indicate that silicon oxide is formed on Si-face surface polished by the slurry including oxidant H 2 O 2 , but not that after immersing in H 2 O 2 solution. UV–vis spectroscopy curves prove that • OH hydroxyl radical could be generated only under CMP polishing by the slurry including H 2 O 2 and abrasive, so as to promote oxidation of Si-face to realize the effective removal; meanwhile, alkali KOH during CMP could induce the production of more radicals to improve the removal. On the other side, ultra-smooth polished surface with atomic step structure morphology and extremely low Ra of about 0.06 nm (through AFM) is obtained using the developed slurry with silica nanoparticle abrasive. Through investigating the variations of the atomic step morphology on the surface polished by different slurries, it's reveals that CMP removal mechanism involves a simultaneous process of surface chemical reaction and nanoparticle atomic scale abrasion

XPS response in the corrosion products analysis for copper exposed at clean air environment

International Nuclear Information System (INIS)

Mariaca, L.; Morcillo, M.; Feliu Jr, S.; Gonzalez, J.A.

1998-01-01

In this work is presented the obtained response for superficial analysis technique by X-ray photoelectron spectroscopy (XPS or ESCA), to determine the corrosion products formed during the copper exposure at environment without pollutants (clean air) at 50, 70 and 90 % of relative humidity at 35 Centigrade. One of the copper corrosion products most knew is Cu 2 O. This oxide is formed instantly to be exposed the copper at air. However in function of the exposure time and the relative humidity at it is exposed, the Cu 2 O oxide is transformed at Cu O and Cu(OH) 2 (Author)

Sub-nanometer resolution XPS depth profiling: Sensing of atoms

Energy Technology Data Exchange (ETDEWEB)

Szklarczyk, Marek, E-mail: szklarcz@chem.uw.edu.pl [Faculty of Chemistry, University of Warsaw, ul. Pasteura 1, 02-093 Warsaw (Poland); Shim-Pol, ul. Lubomirskiego 5, 05-080 Izabelin (Poland); Macak, Karol; Roberts, Adam J. [Kratos Analytical Ltd, Wharfside, Trafford Wharf Road, Manchester, M17 1GP (United Kingdom); Takahashi, Kazuhiro [Kratos XPS Section, Shimadzu Corp., 380-1 Horiyamashita, Hadano, Kanagawa 259-1304 (Japan); Hutton, Simon [Kratos Analytical Ltd, Wharfside, Trafford Wharf Road, Manchester, M17 1GP (United Kingdom); Głaszczka, Rafał [Shim-Pol, ul. Lubomirskiego 5, 05-080 Izabelin (Poland); Blomfield, Christopher [Kratos Analytical Ltd, Wharfside, Trafford Wharf Road, Manchester, M17 1GP (United Kingdom)

2017-07-31

Highlights: • Angle resolved photoelectron depth profiling of nano thin films. • Sensing atomic position in SAM films. • Detection of direction position of adsorbed molecules. - Abstract: The development of a method capable of distinguishing a single atom in a single molecule is important in many fields. The results reported herein demonstrate sub-nanometer resolution for angularly resolved X-ray photoelectron spectroscopy (ARXPS). This is made possible by the incorporation of a Maximum Entropy Method (MEM) model, which utilize density corrected electronic emission factors to the X-ray photoelectron spectroscopy (XPS) experimental results. In this paper we report on the comparison between experimental ARXPS results and reconstructed for both inorganic and organic thin film samples. Unexpected deviations between experimental data and calculated points are explained by the inaccuracy of the constants and standards used for the calculation, e.g. emission factors, scattering intensity and atomic density through the studied thickness. The positions of iron, nitrogen and fluorine atoms were determined in the molecules of the studied self-assembled monolayers. It has been shown that reconstruction of real spectroscopic data with 0.2 nm resolution is possible.

Forame Mentual: verificação da localização por meio de radiografia panorâmica

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Ingrid Macedo de Oliveira

2017-05-01

Full Text Available A topografia do forame mentual é de grande importância na clínica odontológica, porque proporciona a realização de procedimentos seguros na mandíbula; no entanto, sua localização e características podem variar entre as populações. O objetivo do presente estudo foi descrever a topografia e as variações anatômicas do forame mental por meio de radiografias panorâmicas. Sendo um estudo retrospectivo transversal, feito por examinador previamente calibrado, foram analisados os antímeros direito e esquerdo de 100 radiografias panorâmicas, totalizando 200 forames. O forame foi classificado quanto à posição, em relação aos dentes inferiores, e quanto à altura, em relação à base da mandíbula. A análise das radiografias foi realizada sob negatoscópio e com auxílio de paquímetro digital. A estatística foi do tipo descritiva. Quanto à posição dos dentes, observou-se que o forame classe III (62% foi o de maior prevalência, seguido pelos de classe IV (23,5%, classe V (10,5%, classe VI (2% e classes I (1% e II (1%. As maiores alturas encontradas foram de 13mm e 14mm para os lados esquerdo e direito respectivamente. Houve variações na localização do forame mental, com maior prevalência do forame situado entre o primeiro e o segundo pré-molar. Porém houve proximidade entre as dimensões e a localização do forame mental nos dois lados de um mesmo exame radiográfico.

Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

International Nuclear Information System (INIS)

Nelson, O.D.; Keller, G.M.

1997-01-01

This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

XPS and AES investigations of the adhesive bonding properties of thin titanium coatings

International Nuclear Information System (INIS)

Moers, H.; Mohr, J.; Klewe-Nebenius, H.; Pfennig, G.

1988-07-01

The bonding properties of PMMA-microstructures on Ti-coated Cu-substrates after an oxidative treatment in alkaline hydrogenperoxide solution were investigated. In order to clarify the basic mechanism, surface analytical investigations by XPS-, AES-, and depth profile measurements have been performed. It was demonstrated that for optimum bonding a TiO 2 surface layer of ca. 30 nm thickness is necessary. Chemical effects as well as a mechanical bonding with open grain boundary structures (dimensions in the μm-range) could be ruled out as bonding mechanisms. A mechanical interlocking of the polymer with micropores (dimensions in the nm-range) of the oxidic overlayer is adopted as the most probable bonding mechanism. (orig.)

Número mínimo de colheitas em pepino híbrido estimado por meio do coeficiente de repetibilidade Minimum harvest number in hybrid cucumber estimated by repeatability coefficient

Directory of Open Access Journals (Sweden)

Antonio Ismael Inácio Cardoso

2006-01-01

Full Text Available O objetivo deste trabalho foi estimar o número mínimo de colheitas em experimento com a cultura do pepino. Foram analisados dados de um experimento onde avaliaram-se 14 híbridos de pepino japonês, no delineamento em blocos ao acaso, com quatro repetições e cinco plantas por parcela, conduzidas sob ambiente protegido. Foram efetuadas 32 colheitas, três colheitas por semana, por um período de 72 dias e estimados os coeficientes de repetibilidade, com base na análise de componentes principais para os caracteres produção de frutos por planta, em massa e número, total e comercial. Os resultados permitiram concluir que menos de nove colheitas foram suficientes para analisar as diferenças de produtividade entre os diferentes híbridos, com 95% de certeza de serem eleitos os mais produtivos.The objective of this work was to estimate the minimum harvest number in experiments with cucumber. Data of an experiment comparing 14 japanese cucumber hybrids in the randomized block design, with four replications and five plants per plot, under protected cultivation, were analyzed. Thirty-two harvestings were made, three harvests a week, during 72 days to estimate repeatability coefficient based on analysis of the principal components for number and weight of total and commercial fruits per plant. Results allowed to conclude that less than nine harvestings were enough to verify yield differences among hybrids, with 95% of probability to identify the highest yielding ones.

Atomic and Nuclear Analytical Methods XRF, Mössbauer, XPS, NAA and Ion-Beam Spectroscopic Techniques

CERN Document Server

Verma, H R

2007-01-01

This book is a blend of analytical methods based on the phenomenon of atomic and nuclear physics. It comprises comprehensive presentations about X-ray Fluorescence (XRF), Mössbauer Spectroscopy (MS), X-ray Photoelectron Spectroscopy (XPS), Neutron- Activation Analysis (NAA), Particle Induced X-ray Emission Analysis (PIXE), Rutherford Backscattering Analysis (RBS), Elastic Recoil Detection (ERD), Nuclear Reaction Analysis (NRA), Particle Induced Gamma-ray Emission Analysis (PIGE), and Accelerator Mass Spectrometry (AMS). These techniques are commonly applied in the fields of medicine, biology, environmental studies, archaeology or geology et al. and pursued in major international research laboratories.

Producción y tratamiento de películas de Si_1-xGe_x mediante técnicas asistidas por láser de excímero

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Castro, J.

1998-04-01

Full Text Available Heterostructures of Si_1-xGe_x alloys on Si (100 have been achieved using two different excimer laser techniques. The first one, the Laser Induced Chemical Vapour Deposition (LCVD, was used in order to deposit germanium on Si (100 substrates via photolysis of GeH₄ as precursor gas. The resulting films show a very homogeneous and amorphous structure as determined by HREM, XRD and Raman analysis. These deposited amorphous germanium films and a part of their underlaying Si (100 substrate were melted using the second technique, the Pulsed Laser Induced Epitaxy (PLIE, inducing an epitactic recrystallization of a Si-Ge alloy. The analysis of the obtained alloys by HREM, XRD, and XPS, reveals a strong dependence of the crystal quality and of the germanium concentration profile from the number of pulses.

El creciente interés que suscita la búsqueda de nuevas técnicas para la obtención de materiales semiconductores, compatibles con la tecnología del silicio, ha llevado a desarrollar un sistema de depósito y postprocesado en alto vacío (HV de Si-Ge mediante técnicas asistidas por láser excímero. Se han obtenido películas amorfas de germanio mediante el depósito químico en fase vapor inducido por láser (LCVD, que posteriormente han sido recristalizadas con uso de la inducción de epitaxia por medio de láser pulsado (PLIE. Las películas depositadas sobre substratos de silicio fueron caracterizadas mediante XRD, HREM y Raman, revelándose que son amorfas con un alto grado de homogeneidad. Se ha estudiado la morfología y la estequiometría de las muestras por medio de XRD, HREM y XPS tras el tratamiento para inducir la cristalinidad de la aleación sobre el substrato de silicio, observándose la dependencia del grado de heteroepitaxia y variación de la composición en la aleación, con el número y la energía de los pulsos del láser.

A construção e a compreensão de sentido em discursos por crianças entre 10 e 12 anos

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Cristiane Dall Cortivo Lebler

2017-07-01

Full Text Available O presente artigo é fruto de uma pesquisa, de igual nome, que partiu da ideia de que compreender a palavra e as possibilidades que ela delimita ao discurso e que este delimita a ela é essencial para o entendimento do próprio discurso. Sendo assim, este artigo se propõe a pensar sobre a construção e a compreensão de sentido da palavra em discursos, com o embasamento da Teoria da Argumentação na Língua de Oswald Ducrot, Jean-Claude Anscombre e Marion Carel. Escolheu-se observar esse processo em alunos com idade entre 10 e 12 anos e que estão no 5º, 6º ou 7º ano do Ensino Fundamental. Como procedimentos metodológicos, foram realizados estudos teóricos e construção do corpus, a partir do qual houve a elaboração de uma aula introdutória e de um teste. Ambos foram realizados com alunos da faixa etária selecionada e, posteriormente, tiveram seus resultados analisados a fim de encontrar respostas para os objetivos delimitados. Pôde-se constatar que há um olhar crítico dos alunos com relação ao sentido das palavras e das suas diversas possibilidades de significação, mas que ele é, por muitas vezes, encoberto por experiências anteriores com essas palavras, revelando, portanto, uma grande dificuldade, por parte dos alunos, em considerar o contexto discursivo na apreensão do sentido.

Surface modification of pyrolyzed carbon fibres by cyclic voltammetry and their characterization with XPS and dye adsorption

International Nuclear Information System (INIS)

Georgiou, P.; Walton, J.; Simitzis, J.

2010-01-01

Commercial carbon fibres were pyrolyzed up to 1000 deg. C and were then electrochemically treated by cyclic voltammetry in aqueous electrolyte solutions of H 2 SO 4 , in two potential sweep ranges: a narrow region, N, and a wide region, W, avoiding and including water decomposition, respectively. The anodic and cathodic peaks were correlated with oxide formation and their partial reduction, respectively. The nature of oxygen containing groups on the fibre surfaces was determined by XPS. Wide scan spectra and high energy resolution spectra were recorded through the C 1s, O 1s, N 1s and S 2p photoelectron regions. The ability of the fibres to adsorb methylene blue and alizarin yellow dyes from their aqueous solutions indicates the presence of electron acceptor or donor groups on the fibres, respectively. The carbon fibres were classified into two categories. The first includes electrochemically untreated and treated in the N region, and the second those treated in the W region. The high oxygen concentration and effective dye adsorption on the carbon fibres in the second category indicates that their surfaces were effectively modified. The adsorption of dyes on carbon fibres constitutes a complementary method to XPS for an indirect estimation of oxygen and other groups present on the carbon fibre surfaces.

Visita ??ntima na unidade prisional feminina de regime fechado e provis??rio de Palmas/TO: sentidos e significados analisados sob o enfoque fenomenol??gico

OpenAIRE

Paro, Marcelo Laurito

2016-01-01

Relat??rio t??cnico de pesquisa aplicada que teve por objetivo analisar o fen??meno da visita ??ntima na Unidade Prisional Feminina de Palmas/TO, sob a perspectiva das pr??prias mulheres encarceradas. O m??todo fenomenol??gico utilizado mostrou-se o mais adequado aos objetivos propostos de desvelar e revelar os sentidos e significados atribu??dos pelas presidi??rias ?? visita. A coleta de dados deu-se por question??rio semiestruturado e entrevista aberta com uso de pergunta dis...

OTIMIZAÇÃO DO PROCESSO DE PRODUÇÃO DE LEITE CONDENSADO EMPREGANDO PRÉ-CONCENTRAÇÃO POR MEMBRANAS

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Paula Nunes Mendes

2012-06-01

Full Text Available O leite condensado é um dos produtos que apresenta maior crescimento em produção no Brasil, favorecendo o desenvolvimento de novas tecnologias e a adaptação de indústrias de médio e pequeno porte para fabricação deste produto. O objetivo central do presente trabalho foi avaliar os atributos de dois processos de fabricação distintos, sendo o primeiro utilizandose leite padronizado com aproximadamente 12 % de sólidos totais e o segundo leite préconcentrado por osmose reversa, identificando a diferença entre os produtos e o impacto do processo de concentração por membrana em suas características desejáveis. Os experimentos foram realizados numa indústria da Zona da Mata Mineira, com avaliações físico-químicas e sensoriais. Os produtos foram analisados com 1, 30, 60 e 120 dias de fabricação. Concluiu-se que o leite condensado com osmose não apresentou diferença estatisticamente significativa em comparação ao leite condensado sem osmose quanto aos atributos avaliados e foi possível estabelecer relações entre constituintes, com aplicação prática, permitindo definir o teor mínimo de sólidos solúveis para obtenção de uma viscosidade mínima.

Monitoramento do percevejo marrom Euschistus heros (Hemiptera: Pentatomidae por feromônio sexual em lavoura de soja

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Valvenarg Pereira da Silva

2014-11-01

Full Text Available O objetivo deste trabalho foi avaliar a eficiência das formulações septo de borracha e lure do feromônio sexual do percevejo marrom Euschistus heros e compará-la ao método do pano de batida, para o monitoramento dessa praga em lavoura de soja. Os tratamentos foram: feromônio em septo de borracha, feromônio em lure e amostragem com pano de batida. As amostragens foram realizadas semanalmente durante a fase reprodutiva da soja (dez semanas. Para estimar a densidade populacional de percevejos e compará-la à captura nas armadilhas de feromônio, foram efetuados quatro panos de batida por semana em todas as parcelas; além disso, foi determinado o número de percevejos capturados nas armadilhas por semana. Os danos provocados pelos percevejos nas sementes foram analisados pelo teste de tetrazólio. As formulações do feromônio foram eficientes na captura de E. heros, e a formulação em lure capturou mais percevejos. O controle precoce da população, indicado pelo nível de controle nas armadilhas com feromônio, resultou em sementes com maior qualidade do que as provenientes das parcelas monitoradas pelo pano de batida. Assim, as armadilhas com feromônio são mais eficientes que o pano de batida para o monitoramento das populações de percevejos durante a fase crítica do ataque deste inseto nas lavouras de soja.

Estudo da degradação do fármaco Nabumetona por fotólise direta Study of Nabumetone degradation through direct photolysis

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Florangela Maionchi

2002-03-01

Full Text Available O presente trabalho teve por objetivo estudar a degradação do fármaco Nabumetona por fotólise direta. Soluções etanólicas de amostras (20 mg/mL foram preparadas e divididas em cubetas de quartzo com tampas de teflon. Estas foram colocadas em uma câmara de fotólise à temperatura de 35ºC. As quantificações das fotodegradações foram analisadas por Cromatografia Líquida de Alta Eficiência (CLAE; após 47 dias de fotólise, a degradação da amostra foi de 67%, após 73 dias 88,5% e após 111 dias 89,5%. Determinações espectrofotométricas (240 a 360 nm foram realizadas após 28, 47 e 73 dias de fotólise. Os fotoprodutos foram separados por CLAE e analisados por Cromatografia Gasosa Acoplada ao Espectro de Massa de Baixa Resolução (CG-EM. A análise em CG-EM da Nabumetona fotolisada durante 111 dias permitiu a sugestão de duas substâncias.The present work aims to study the degradation of Nabumetone through direct photolysis. Solutions of Nabumetone in ethanol (20 mg/mL were prepared and divided in quartz cuvettes with teflon lids. These were placed in the photolysis cabinet at 35ºC. The photodegradation quantifications were analyzed in High Performance Liquid Cromatography (HPLC; after 47 days of photolysis the sample degradation was 67%, after 73 days 88.5% and after 111 days 89.5%. Spectrophotometers determinations (240 to 360 nm were accomplished after 28, 47 and 73 days of photolysis. The photoproducts were separate for HPLC and analyzed by Gas Cromatograph coupled to Mass Spectrometer (GC-MS. The analysis in GC-MS of the Nabumetona photolyseded for 111 days allowed the suggestion of two substances.

XPS and ToF-SIMS analysis of natural rubies and sapphires heat-treated in a reducing (5 mol% H 2/Ar) atmosphere

Science.gov (United States)

Achiwawanich, S.; James, B. D.; Liesegang, J.

2008-12-01

Surface effects on Mong Hsu rubies and Kanchanaburi sapphires after heat treatment in a controlled reducing atmosphere (5 mol% H 2/Ar) have been investigated using advanced surface science techniques including X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Visual appearance of the gemstones is clearly affected by the heat treatment in a reducing atmosphere. Kanchanaburi sapphires, in particular, exhibit Fe-containing precipitates after the heat treatment which have not been observed in previous studies under an inert atmosphere. Significant correlation between changes in visual appearance of the gemstones and variations in surface concentration of trace elements, especially Ti and Fe are observed. The XPS and ToF-SIMS results suggest that; (1) a reducing atmosphere affects the oxidation state of Fe; (2) dissociation of Fe-Ti interaction may occur during heat treatment.

Quantification of the toxic hexavalent chromium content in an organic matrix by X-ray photoelectron spectroscopy (XPS) and ultra-low-angle microtomy (ULAM)

Energy Technology Data Exchange (ETDEWEB)

Greunz, Theresia, E-mail: theresia.greunz@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Duchaczek, Hubert; Sagl, Raffaela [voestalpine Stahl GmbH, voestalpine-Straße 3, 4031 Linz (Austria); Duchoslav, Jiri; Steinberger, Roland [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Strauß, Bernhard [voestalpine Stahl GmbH, voestalpine-Straße 3, 4031 Linz (Austria); Stifter, David [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria)

2017-02-28

Highlights: • Common methods are not suitable for a reliable determination of Cr(VI) in organic coatings on steel. • Our proposed method is a combination of XPS and ultra-low-angle microtomy (ULAM). • The results allow referring to legal regulations of the Cr(VI) concentration. • For this method no accurate sample parameters are required. - Abstract: Cr(VI) is known for its corrosion inhibitive properties and is, despite legal regulations, still a potential candidate to be added to thin (1–3 μm) protective coatings applied on, e.g., electrical steel as used for transformers, etc. However, Cr(VI) is harmful to the environment and to the human health. Hence, a reliable quantification of it is of decisive interest. Commonly, an alkaline extraction with a photometric endpoint detection of Cr(VI) is used for such material systems. However, this procedure requires an accurate knowledge on sample parameters such as dry film thickness and coating density that are occasionally associated with significant experimental errors. We present a comprehensive study of a coating system with a defined Cr(VI) pigment concentration applied on electrical steel. X-ray photoelectron spectroscopy (XPS) was employed to resolve the elemental chromium concentration and the chemical state. Turning to the fact that XPS is extremely surface sensitive (<10 nm) and that the lowest commonly achievable lateral resolution is a number of times higher than the coating thickness (∼2 μm), a bulk analysis was achieved with XPS line scans on extended wedge-shaped tapers through the coating. For that purpose a special sample preparation step performed on an ultra-microtome was required prior to analysis. Since a temperature increase leads to a reduction of Cr(VI) we extend our method on samples, which were subjected to different curing temperatures. We show that our proposed approach now allows to determine the elemental and Cr(VI) concentration and distribution inside the coating.

Abordagens semiquantitativa e quantitativa na avaliação da textura do solo por espectroscopia de reflectância bidirecional no VIS-NIR-SWIR

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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.

Stability of boron-doped graphene/copper interface: DFT, XPS and OSEE studies

Science.gov (United States)

Boukhvalov, D. W.; Zhidkov, I. S.; Kukharenko, A. I.; Slesarev, A. I.; Zatsepin, A. F.; Cholakh, S. O.; Kurmaev, E. Z.

2018-05-01

Two different types of boron-doped graphene/copper interfaces synthesized using two different flow rates of Ar through the bubbler containing the boron source were studied. X-ray photoelectron spectra (XPS) and optically stimulated electron emission (OSEE) measurements have demonstrated that boron-doped graphene coating provides a high corrosion resistivity of Cu-substrate with the light traces of the oxidation of carbon cover. The density functional theory calculations suggest that for the case of substitutional (graphitic) boron-defect only the oxidation near boron impurity is energetically favorable and creation of the vacancies that can induce the oxidation of copper substrate is energetically unfavorable. In the case of non-graphitic boron defects oxidation of the area, a nearby impurity is metastable that not only prevent oxidation but makes boron-doped graphene. Modeling of oxygen reduction reaction demonstrates high catalytic performance of these materials.

Chemical state analysis of heat-treated 6, 13-bis(triisopropylsilylethynyl) pentacene investigated by XPS valence band spectra, XANES spectra and first-principles calculation

International Nuclear Information System (INIS)

Muro, Maiko; Natsume, Yutaka; Kikuma, Jun; Setoyama, Hiroyuki

2014-01-01

X-ray photoelectron spectroscopy (XPS) valence band spectra reflect the chemical bonding states. To take this advantage, we tried to interpret experimental spectra by the occupied density of states (DOS) based on first principles calculation. In this work, we discussed XPS and X-ray Absorption Near Edge Structure (XANES) spectra of 6, 13-bis(triisopropylsilylethynyl) pentacene (TIPS-Pen), which is well known as an organic semiconductor. We studied chemical structure change of TIPS-Pen caused by heat-treatment at 300degC under nitrogen and under the air. It has been suggested that the structural change of pentacene skeleton by Diels-Alder type reaction occurs in both cases. In addition, the sample heat-treated under the air showed desorption of the isopropyl group and increase of oxygen concentration. (author)

CUANTIFICACIÓN DE ARSÉNICO POR ABSORCIÓN ATÓMICA EN TERMOFORMADOS Y PELÍCULAS FLEXIBLES BIODEGRADABLES QUANTIFICAÇÃO DE ARSÊNIO POR ABSORÇÃO ATÔMICA EM TERMOFORMADOS E PELÍCULAS FLEXÍVEIS BIODEGRADÁVEIS QUANTIFICATION OF ARSENIC BY ATOMIC ABSORPTION SPECTROMETRY IN FLEXIBLE THERMOFORMED AND BIODEGRADABLE FILMS

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LEIDY FERNANDA ALVIRA M

2012-06-01

Full Text Available Se determinó la concentración de arsénico en siete muestras de termoformados y seis muestras de películas flexibles biodegradables, por espectrometría de absorción atómica con generador de hidruros; el método de cuantificación fue curva de calibración a 193,7 nm. Previamente a ésta cuantificación, se optimizó el proceso de digestión ácida mediante reflujo (HNO3:HClO4, relación 3:1, 70°C, 3 horas para termoformados y 45 minutos para películas flexibles y se implementaron y estandarizaron los parámetros de calidad estadística (Límite de detección y cuantificación, intervalo lineal, sensibilidad de calibración, precisión y exactitud. Los resultados obtenidos fueron analizados empleando el paquete estadístico SPSS. Las concentraciones de arsénico en termoformados fueron detectables en el rango de las partes por billón mientras que las películas flexibles fueron no detectables. Hoy en día, no existe una normativa vigente que establezca los valores permitidos de Arsénico para los biopolímeros analizados.Determinou-se a concentração de arsênio em sete amostras de termoformados e seis amostras de películas flexíveis biodegradáveis, por espectrometria de absorção atômica com gerador de hidretos. O método de quantificação foi por Curva de Calibração a 193,7nm. Previamente a esta quantificação, otimizou-se o processo de digestão ácida mediante refluxo (HNO3:HClO4, relação 3:1, 70°C, 3 horas para termoformados e 45 minutos para películas flexíveis implementando e padronizando os parâmetros de qualidade estatística (Limite de detecção e quantificação, intervalo linear, sensibilidade de calibração, precisão e exatidão. Os resultados obtidos foram analisados empregando o pacote estatístico SPSS. As concentraçôes de arsênio em termoformados foram detectáveis no intervalo das partes por milhão enquanto as películas flexíveis não foram detectáveis. Hoje em dia, não existe uma normativa

Multiwalled Carbon Nanotube Forest Grown via Chemical Vapor Deposition from Iron Catalyst Nanoparticles, by XPS

Energy Technology Data Exchange (ETDEWEB)

Jensen, David S.; Kanyal, Supriya S.; Madaan, Nitesh; Vail, Michael A.; Dadson, Andrew; Engelhard, Mark H.; Linford, Matthew R.

2013-09-25

Carbon nanotubes (CNTs) have unique chemical and physical properties. Herein, we report an XPS analysis of a forest of multiwalled CNTs using monochromatic Al Kα radiation. Survey scans show only one element: carbon. The carbon 1s peak is centered 284.5 eV. The C 1s envelope also shows the expected π → π* shake-up peak at ca. 291 eV. The valence band and carbon KVV Auger signals are presented. When patterned, the CNT forests can be used as a template for subsequent deposition of metal oxides to make thin layer chromatography plates.1-3

Barreiras no tratamento da infecção latente por tuberculose (ILTB na criança: um estudo de caso

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Adriana Rodrigues da Silva

2014-09-01

Full Text Available Objetivo: Analisar as barreiras enfrentadas pelo familiar no tratamento da infecção latente por tuberculose (ILTB na criança. Métodos: Estudo descritivo, em duas etapas. Na primeira, analisados prontuários de crianças de 0 a 11 anos tratadas para ILTB em um centro municipal de saúde no Município do Rio de Janeiro. Na segunda, entrevista com os familiares. Nas duas etapas buscou-se identificar barreiras pessoais, familiares, econômicas, sociais e do serviço. Resultados: Primeira etapa; houve barreiras (47/228: no serviço - 4 (8,5%; pessoais - 4 (8,5%; familiares - 21 (44,7%; fisiológicas - 12 (25,5%. Na segunda; houve barreiras (50/85: econômicas - 19 (38%; sociais - 13 (26%; pessoais e familiares - 18 (36%. Conclusão: Fatores socioeconômicos desfavoráveis afetaram o cuidado da criança nas duas etapas do estudo. Repensar na forma de lidar com os determinantes sociais associados à tuberculose pode ser o caminho para evitar abandono e interrupções deste tratamento.

Análise do produtor-consumidor enquanto interveniente da rede elétrica inteligente

OpenAIRE

Pereira, David Miguel Gonçalves

2014-01-01

Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia Neste trabalho é analisado o desempenho dos intervenientes da rede elétrica, desde os consumidores aos produtores, prosumers, operadores de rede e reguladores de sistemas. Entende-se por prosumer, qualquer utilizador que é simultaneamente consumidor e produtor de energia elétrica. É também analisado o comportamento dosprosumers baseado em cenários. É realizada a previsão ...

XPS study on the electronic structure of hydrided Ti-V, Ti-Nb and Ti-Mo alloys

International Nuclear Information System (INIS)

Tanaka, Kazuhide; Aoki, Hiromasa

1989-01-01

Effects of hydrogenation on the core and valence electronic structures of β(bcc)-stabilized Ti-25at%V, Ti-50at%Nb and Ti-20at%Mo alloys are studied with XPS technique using monochromatized Al K α radiation. Small but uniform binding-energy shifts are observed upon hydrogenation for all the core spectra measured. Their valence-band spectra are significantly distorted, providing an evidence of the formation of metal-hydrogen bonding bands in these Ti alloys. Interrelations between the core binding-energy shifts and the valence-band distortion are discussed. (orig.)

XPS study on the surface reaction of uranium metal with carbon monoxide at 200 degree C

International Nuclear Information System (INIS)

Wang Xiaoling; Fu Yibei; Xie Renshou; Huang Ruiliang

1996-12-01

The surface reaction of uranium metal with carbon monoxide at 200 degree C has been studied by X-ray photoelectron spectroscopy (XPS). The carbon monoxide adsorption on the surface oxide layer resulted in U4f peak shifting to the lower binding energy and the content of oxygen in the oxide is decreased. O/U radio decreases with increasing the exposure of carbon monoxide to the surface layer. The investigation indicated the surface layer of uranium metal was further reduced in the atmosphere of carbon monoxide at high temperature. (3 refs., 5 figs.)

Celulitis por citomegalovirus

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A. Ruiz Lascano

2002-12-01

Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

Characterization of Sr2+ uptake on natural minerals of kaolinite and magnesite using XRPD, SEM/EDS, XPS, and DRIFT

International Nuclear Information System (INIS)

Shahwan, T.; Erten, H.N.

2005-01-01

The sorption behavior of Sr 2+ ions on natural minerals rich in kaolinite and magnesite was studied using SEM/EDS, XPS, XRPD, AAS/AES and DRIFT techniques. Quantitative analysis of the XPS data shows that magnesite is more effective in Sr 2+ uptake than kaolinite. DRIFT spectra and XRPD patterns indicate that the structures of both minerals were not affected upon Sr 2+ sorption. Intercalation of DMSO in kaolinite lamellae aiming at increasing the interlayer space did not significantly enhance the sorption capacity of the clay towards Sr 2+ probably due to the lack of a negative charge on the accessible sites. EDS mapping indicated that while the sorbed Sr is equally distributed on surface of natural kaolinite, it was associated - to a larger extent - with the regions richer in Mg in the case of natural magnesite. Comparing the uptake mechanisms of natural magnesite with that of pure MgCO 3 , it was seen that while natural magnesite sorbed Sr 2+ mainly through an ion exchange type mechanism, the formation of SrCO 3 coprecipitate was detected on the surface of the MgCO 3 at higher loadings. (orig.)

Initial surface film on magnesium metal: A characterization by X-ray photoelectron spectroscopy (XPS) and photocurrent spectroscopy (PCS)

International Nuclear Information System (INIS)

Santamaria, M.; Di Quarto, F.; Zanna, S.; Marcus, P.

2007-01-01

A detailed investigation of the initial film grown on mechanically polished Mg electrodes has been carried out by ex situ X-ray Photoelectron Spectroscopy (XPS) and in situ Photocurrent Spectroscopy (PCS), allowing to reach a detailed picture of the passive layer structure. The XPS data show that the films formed soon after mechanical treatment and immersion in aqueous electrolyte have a bilayer structure, consisting of an ultra-thin MgO inner layer (∼2.5 nm) and a Mg(OH) 2 external layer. The thickness of the Mg(OH) 2 layer is a function of immersion time and solution temperature. After mechanical treatment and immersion in aqueous solution at room temperature, the MgO/Mg(OH) 2 layer in some area of electrodes is so thin to allow an electron photoemission process from the Mg Fermi level to the electrolyte conduction band. Only internal photoemission processes are evidenced for Mg electrodes aged in NaOH at 80 deg. C, due the formation of a thicker Mg(OH) 2 layer. From anodic photocurrent spectra an optical band gap of ∼4.25 eV has been estimated for Mg(OH) 2 , lower with respect to the optical gap of the corresponding anhydrous counterpart

XPS study of the passive films formed on nitrogen-implanted austenitic stainless steels

International Nuclear Information System (INIS)

Marcus, P.; Bussell, M.E.

1992-01-01

Austenitic stainless steels (304-type) have been implanted with nitrogen ions in order to investigate the effects of implanted nitrogen on their electrochemical behaviour and on the nature of the passive film formed on the steels in acid (0.5M H 2 SO 4 ). Alloys with two nitrogen doses have been prepared (2.5x10 16 and 2x10 17 N atoms/cm 2 ). The implanted alloys have been characterized by 15 N-NRA (nuclear reaction analysis) and XPS (X-ray photoelectron spectroscopy). Alloy surfaces with well-defined N concentrations were prepared, prior to the electrochemical measurements, by argon-ion sputtering of the implanted material for a fixed time in order to reach a well-defined point on the nitrogen depth profile. The samples were then transferred without exposure to air to an electrochemical cell mounted in an inert gas glove box. The implanted nitrogen modifies the electrochemical behaviour of the alloy. The anodic dissolution in the active state is enhanced, and the current density in the passive state is increased. Surface analysis of the alloys by XPS after passivation shows that implanted nitrogen is enriched on the surface during dissolution and passivation of the alloys. The process by which N is enriched on the surface is anodic segregation, which was first observed and characterized for S on Ni and Ni-Fe alloys. The passive films formed on both the unimplanted and implanted alloys have a bilayer structure with an inner oxide layer and an outer hydroxide layer, but on the nitrogen-implanted alloy, a chromium nitride phase is formed at the expense of the chromium oxide. After passivation of the implanted alloys, three chemical states of nitrogen are detected in the N 1s spectrum. The high binding energy (399.4 eV) peak corresponds to a nitrogen species located on the surface of the passive film, which is produced by reaction of the implanted nitrogen with the solution. (orig./WL)

An Auger and XPS survey of cerium active corrosion protection for AA2024-T3 aluminum alloy

Energy Technology Data Exchange (ETDEWEB)

Uhart, A. [IPREM-ECP-UMR CNRS 5254, Université de Pau et des Pays de l' Adour, Technopole Hélioparc, 2 Avenue Président Pierre Angot, 64053 Pau Cedex 09 (France); Ledeuil, J.B. [IPREM-ECP-UMR CNRS 5254, Université de Pau et des Pays de l' Adour, Technopole Hélioparc, 2 Avenue Président Pierre Angot, 64053 Pau Cedex 09 (France); Université de Toulouse, UPS-INP-CNRS, Institut Carnot CIRIMAT, 118 Route de Narbonne, 31062 Toulouse Cedex 09 (France); Gonbeau, D. [IPREM-ECP-UMR CNRS 5254, Université de Pau et des Pays de l' Adour, Technopole Hélioparc, 2 Avenue Président Pierre Angot, 64053 Pau Cedex 09 (France); Dupin, J.C., E-mail: dupin@univ-pau.fr [IPREM-ECP-UMR CNRS 5254, Université de Pau et des Pays de l' Adour, Technopole Hélioparc, 2 Avenue Président Pierre Angot, 64053 Pau Cedex 09 (France); Bonino, J.P.; Ansart, F. [Université de Toulouse, UPS-INP-CNRS, Institut Carnot CIRIMAT, 118 Route de Narbonne, 31062 Toulouse Cedex 09 (France); Esteban, J. [Messier-Bugatti-Dowty, Etablissement de Molsheim, 3, rue Antoine de St Exupéry, 67129 Molsheim (France)

2016-12-30

Graphical abstract: Coupled SAM/SEM survey of cerium inhibitor migration towards corrosion pits in a conversion coating over AA2024-T3 substrate. - Highlights: • XPS evidenced the proximity of the inhibitor with the surface AA2024 alloy. • Cerium conversion coatings with [Ce] = 0.1 M offer the best corrosion resistance. • SAM shown the migration of Ce + III entities towards the corrosion pits or crevices. • High resolution analyses (Auger) connecting the nano-scale order with the chemical distribution.

XPS and ToF-SIMS analysis of natural rubies and sapphires heat-treated in a reducing (5 mol% H{sub 2}/Ar) atmosphere

Energy Technology Data Exchange (ETDEWEB)

Achiwawanich, S. [Department of Physics, La Trobe University, VIC 3086 (Australia); Centre for Materials and Surface Science, La Trobe University, VIC 3086 (Australia); James, B.D. [Centre for Materials and Surface Science, La Trobe University, VIC 3086 (Australia); Department of Chemistry, La Trobe University, VIC 3086 (Australia); Liesegang, J. [Department of Physics, La Trobe University, VIC 3086 (Australia); Centre for Materials and Surface Science, La Trobe University, VIC 3086 (Australia)], E-mail: J.Liesegang@latrobe.edu.au

2008-12-30

Surface effects on Mong Hsu rubies and Kanchanaburi sapphires after heat treatment in a controlled reducing atmosphere (5 mol% H{sub 2}/Ar) have been investigated using advanced surface science techniques including X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Visual appearance of the gemstones is clearly affected by the heat treatment in a reducing atmosphere. Kanchanaburi sapphires, in particular, exhibit Fe-containing precipitates after the heat treatment which have not been observed in previous studies under an inert atmosphere. Significant correlation between changes in visual appearance of the gemstones and variations in surface concentration of trace elements, especially Ti and Fe are observed. The XPS and ToF-SIMS results suggest that; (1) a reducing atmosphere affects the oxidation state of Fe; (2) dissociation of Fe-Ti interaction may occur during heat treatment.

On the nature of oxygen-containing surface groups on carbon nanofibers and their role for platinum deposition—an xps and titration study

NARCIS (Netherlands)

Plomp, A.J.; Su, D.S.; de Jong, K.P.; Bitter, J.H.

2009-01-01

XPS and acid−base titrations were used to investigate the nature and stability of oxygen-containing surface groups on carbon nanofibers (CNF) and platinum-containing CNF. During heat treatments in inert atmosphere at 973 K all acidic (carboxylic) oxygen surface groups were removed for CNF.

Plasma-oxidation of Ge(100)-surfaces characterized by MIES, UPS and XPS

Energy Technology Data Exchange (ETDEWEB)

Wegewitz, Lienhard; Dahle, Sebastian; Maus-Friedrichs, Wolfgang [Institut fuer Energieforschung und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstr. 4, 38678 Clausthal-Zellerfeld (Germany); Hoefft, Oliver; Endres, Frank [Institut fuer Mechanische Verfahrenstechnik, Technische Universitaet Clausthal, Arnold-Sommerfeld-Str. 6, 38678 Clausthal-Zellerfeld (Germany); Vioel, Wolfgang [HAWK Goettingen, Fakultaet Naturwissenschaften und Technik, Von-Ossietzky-Str. 99, 37085 Goettingen (Germany)

2011-07-01

Cleaning and passivation of Germanium surfaces is of tremendous technological interest. Germanium has various applications, for example in complementary metal-oxide-semiconductor elements. It turned out to be difficult to prepare contamination free Germanium surfaces by methods of wet chemistry. Several attempts have been made preparing such surfaces by different plasma treatments. We report cleaning and passivation of Ge(100)-surfaces by dielectric barrier discharge plasma at ambient temperature in oxygen and in air studied by Metastable Induced Electron Spectroscopy (MIES) and Photoelectron Spectroscopy (UPS(He I) and XPS). The plasma treatment is carried out in a special high-vacuum chamber which operates up to ambient pressure and is directly connected to the ultra-high vacuum chamber including the analysis equipment. In summary the air plasma treatment as well as the oxygen plasma treatment result in contamination free GeO{sub 2} covered surfaces.

Corrosion behaviour of Ni in aprotic solvents an electrochemical, XPS and AFM study

International Nuclear Information System (INIS)

Bellucci, F.; Monetta, T.; Capobianco, G.; Deganello, A.; Glisenti, A.; Moretti, G.

1998-01-01

Electrochemical and X-ray photoelectron spectroscopic (XPS) techniques have been used to study the passivation of nickel in 0.1 M H 2 SO 4 DMF and ACN solutions with different water content. Electrochemical results indicate the anodic formation of a thin, poor protective layer and the possibility of salt precipitation onto the metallic surface. ARXPS results indicate that while in the anodic film formed in DMF, Ni(OH) 2 constitute the superficial component under which a discontinuous layer of NiO and NiSO 4 is present. Ni(OH) 2 and NiSO 4 are the more superficial constituents in the passivation layer formed in ACN, while NiO becomes prevalent in the underlying layers. AFM images show that in both the solvents the sample surface is very dishomogeneous with flakes and fractures. (orig.)

Study on the surface reaction of uranium metal in hydrogen atmosphere with XPS

International Nuclear Information System (INIS)

Wang Xiaolin; Fu Yibei; Xie Renshou; Zuo Changming; Zhao Chunpei; Chen Hong

1998-01-01

The surface reactions of uranium metal in hydrogen atmosphere at 25 degree C and 200 degree C and effects of temperature and carbon monoxide to the hydriding reaction have been studied by X-ray photoelectron spectroscopy (XPS). The reaction between H 2 and uranium metal at 25 degree C leads to the further oxidation of surface layer of metal due to traces of water vapor. At 200 degree C, it may lead to the hydriding reaction of uranium and the hydriding increases with increasing exposure to H 2 in the initial stages. The U4f 7/2 binding energy of UH 3 has been found to be 378.6 eV. Investigation indicates carbon monoxide inhibits both the hydriding reaction and oxidation on the condition of H 2 -CO atmosphere

Surface analysis of glass fibres using XPS and AFM: case study of glass fibres recovered from the glass fibre reinforced polymer using chemical recycling

Science.gov (United States)

Nzioka, A. M.; Kim, Y. J.

2018-01-01

In this study, we present the results of an experimental study of the use of the X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) to characterise the coatings of the recovered E - glass fibres. The recovered E - glass fibres were obtained using chemical recycling process coupled with ultrasound cavitation. The objective of this study was to analyse the impact of chemical recycling and the ultrasound cavitation process on the sizing properties of the recovered fibres. We obtained the recovered fibres and sized using 1 wt% 3 - aminopropyltriethoxysilane (APS). Part of the sized fibres was washed with acetone and analysed all the sample fibres using AFM and XPS. Results showed the different composition of sizing after extraction using acetone. We compared the results of this study with that of virgin clean glass fibres.

Utilização dos equipamentos de proteção individual por mototaxistas: percepção dos fatores de risco e associados

Directory of Open Access Journals (Sweden)

Jules Ramon Brito Teixeira

2014-04-01

Full Text Available Este estudo objetivou analisar as práticas e percepções de mototaxistas a respeito do uso dos equipamentos de proteção individual (EPI por meio de pesquisa de campo, exploratório- descritiva, de abordagem qualitativa. Foram entrevistados trinta mototaxistas do Município de Jequié, Bahia, Brasil. Para a coleta dos dados, foi utilizada a entrevista semiestruturada, e, como instrumento, o questionário. Os dados foram analisados pela Análise de Conteúdo Temático. Os resultados evidenciaram: Categoria 1 – percepção de risco, subcategoria – condicionantes/determinantes para o uso do EPI; Categoria 2 – adesão, subcategoria – adesão ao uso do equipamento de proteção ocupacional; Categoria 3 – o uso do EPI como fator de proteção em acidentes no trânsito, subcategorias 1 – acidentes ocupacionais, 2 – uso do EPI no momento do acidente, 3 – não uso do EPI no momento do acidente. Por fim, tornou-se explícito que os mototaxistas têm algum conhecimento acerca dos equipamentos de proteção ocupacional e, inclusive, atribuem importância ao devido uso desses instrumentos, entretanto, nem sempre fazem o uso adequado deles.

In-situ XPS analysis of oxidized and reduced plasma deposited ruthenium-based thin catalytic films

Science.gov (United States)

Balcerzak, Jacek; Redzynia, Wiktor; Tyczkowski, Jacek

2017-12-01

A novel in-situ study of the surface molecular structure of catalytically active ruthenium-based films subjected to the oxidation (in oxygen) and reduction (in hydrogen) was performed in a Cat-Cell reactor combined with a XPS spectrometer. The films were produced by the plasma deposition method (PEMOCVD). It was found that the films contained ruthenium at different oxidation states: metallic (Ru0), RuO2 (Ru+4), and other RuOx (Ru+x), of which content could be changed by the oxidation or reduction, depending on the process temperature. These results allow to predict the behavior of the Ru-based catalysts in different redox environments.

XPS Analysis of Ni and Oxygen in Single-Sintered SrTiO3 Multifunction Ceramic

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

XPS analyses have been performed to investigate the chemical conditions of Ni and oxygen on grain surfaces in single-sintered SrTiO3 capacitor-varistor ceramic doped with Nb2O5 and NiO. It is ascertained that Ni is in form of Ni2+ ions, which substitute for Ti4+ ions on grain surfaces during the oxidizing annealing. Moreover, it is confirmed that three kinds of chemically adsorbed oxygen such as O2-, O- and O~ are formed on grain surfaces. It is proposed that these behaviors contribute greatly to the generation of multiple types of grain boundary acceptor states in the ceramic.

Execução de Projetos de REDD+ no Brasil Por Meio de Diferentes Modalidades de Financiamento

Directory of Open Access Journals (Sweden)

Guilherme Piffer Salles

Full Text Available Resumo: No âmbito dos acordos globais sobre mudanças climáticas, o mecanismo para Redução de Emissões por Desmatamento e Degradação Florestal (REDD+ tem sido colocado como central para o incentivo econômico às medidas de mitigação envolvendo os ecossistemas florestais. O presente trabalho objetiva analisar as diferenças e as semelhanças dos projetos de REDD+ no Brasil sob distintas modalidades de financiamento, baseadas em fundos públicos ou no mercado de carbono. Utilizando testes de hipótese, dados são analisados, coletados em bases de dados de acesso público, para 18 variáveis de 89 projetos piloto, aprovados sob o mercado voluntário de carbono e sob o Fundo Amazônia. Verifica-se que os projetos sob cada modalidade de financiamento têm várias diferenças entre si, como as relativas a participantes, prazos, abrangência e práticas de Monitoramento, Relato e Verificação. Por outro lado, como aspecto semelhante, recorrem tanto aos pagamentos em dinheiro quanto aos incentivos não monetários, como fortalecimento institucional e provimento de infraestrutura. Isso explicita os esforços destes projetos em adaptar-se às complexidades do contexto florestal e à eficiência necessária para garantir resultados esperados do REDD+. Argumenta-se, assim, em favor da adoção de modalidades mistas de financiamento, capazes de incentivar simultaneamente projetos sob fundos públicos e sob mercados de carbono.

Electronic state of cerium-based catalysts studied by spectroscopic methods (XPS, XAS)

International Nuclear Information System (INIS)

Le Normand, F.; Bernhardt, P.; Hilaire, L.; Kili, K.; Maire, G.; Krill, G.

1987-01-01

X-ray Photoelectron Spectroscopy (XPS) of the 3d core level of cerium and X-ray Absorption Spectroscopy (XAS) of the L III absorption edge of cerium have been used to study Pd/CeO 2 , Pd-Ce/γAl 2 O 3 and Ce/γAl 2 O 3 catalysts. The oxidation state of cerium was found to decrease with decreasing amounts of cerium on the surface. It was quite close to III for very low contents of cerium (2-3%). For higher cerium contents the oxidation state was nearer to IV but differences between the two methods were found, owing to the fact that XAS is a volume sensitive probe. The oxidation state of cerium was also lower for Pd-Ce/γAl 2 O 3 than for Ce/γAl 2 O 3 , suggesting the formation of Ce III OCl, chlorine coming from the precursor salt of palladium. 15 refs.; 5 figs.; 1 table

Portable exhauster POR-007/Skid E and POR-008/Skid F storage plan

International Nuclear Information System (INIS)

Nelson, O.D.

1998-01-01

This document provides storage requirements for 1,000 CFM portable exhausters POR-O07/Skid E and POR-008/Skid F. These requirements are presented in three parts: preparation for storage, storage maintenance and testing, and retrieval from storage. The exhauster component identification numbers listed in this document contain the prefix POR-007 or POR-008 depending on which exhauster is being used

XPS-nanocharacterization of organic layers electrochemically grafted on the surface of SnO_2 thin films to produce a new hybrid material coating

International Nuclear Information System (INIS)

Drevet, R.; Dragoé, D.; Barthés-Labrousse, M.G.; Chaussé, A.; Andrieux, M.

2016-01-01

Graphical abstract: An innovative hybrid material layer is synthesized by combining two processes. SnO_2 thin films are deposited by MOCVD on Si substrates and an organic layer made of carboxyphenyl moieties is electrochemically grafted by the reduction of a diazonium salt. XPS characterizations are carried out to assess the efficiency of the electrochemical grafting. Display Omitted - Highlights: • An innovative hybrid material layer is synthesized by combining two processes. • SnO_2 thin films are deposited by MOCVD on Si substrates. • An organic layer is electrochemically grafted by the reduction of a diazonium salt. • The efficiency of the grafting is accurately assessed by XPS. • Three electrochemical grafting models are proposed. - Abstract: This work presents the synthesis and the characterization of hybrid material thin films obtained by the combination of two processes. The electrochemical grafting of organic layers made of carboxyphenyl moieties is carried out from the reduction of a diazonium salt on tin dioxide (SnO_2) thin films previously deposited on Si substrates by metal organic chemical vapor deposition (MOCVD). Since the MOCVD experimental parameters impact the crystal growth of the SnO_2 layer (i.e. its morphology and its texturation), various electrochemical grafting models can occur, producing different hybrid materials. In order to evidence the efficiency of the electrochemical grafting of the carboxyphenyl moieties, X-ray Photoelectron Spectroscopy (XPS) is used to characterize the first nanometers in depth of the synthesized hybrid material layer. Then three electrochemical grafting models are proposed.

Surface state modulation through wet chemical treatment as a route to controlling the electrical properties of ZnO nanowire arrays investigated with XPS

International Nuclear Information System (INIS)

Lord, Alex M.; Maffeis, Thierry G.; Allen, Martin W.; Morgan, David; Davies, Philip R.; Jones, Daniel R.; Evans, Jonathan E.; Smith, Nathan A.; Wilks, Steve P.

2014-01-01

Highlights: • Direct measurement of the surface band bending exhibited by ZnO nanowires using monochromatic XPS. • Modulation of the surface depletion region using wet chemical treatment (EtOH, H 2 O 2 ). • The measured surface potential barrier agrees with electrical measurements of individual nanowires. • H 2 O 2 depletes the nanowire of charge carriers while EtOH donates electrons at the surface. • EtOH has the effect of restoring the surface potential barrier of oxidised nanowires. - Abstract: ZnO is a wide bandgap semiconductor that has many potential applications including solar cell electrodes, transparent thin film transistors and gas/biological sensors. Since the surfaces of ZnO materials have no amorphous or oxidised layers, they are very environmentally sensitive, making control of their semiconductor properties challenging. In particular, the electronic properties of ZnO nanostructures are dominated by surface effects while surface conduction layers have been observed in thin films and bulk crystals. Therefore, the ability to use the ZnO materials in a controlled way depends on the development of simple techniques to modulate their surface electronic properties. Here, we use monochromatic x-ray photoelectron spectroscopy (XPS) to investigate the use of different wet chemical treatments (EtOH, H 2 O 2 ) to control the electronic properties of ZnO nanowires by modulating the surface depletion region. The valence band and core level XPS spectra are used to explore the relationship between the surface chemistry of the nanowires and the surface band bending

Papel dos medicamentos nas intoxicações causadas por agentes químicos em município da Bahia, no período de 2007 a 2010

Directory of Open Access Journals (Sweden)

Amanda dos Santos Teles

2013-04-01

Full Text Available A intoxicação medicamentosa é um problema de grande relevância para a saúde pública. No Brasil, os medicamentos são os principais agentes responsáveis por intoxicações humanas. Este artigo objetivou descrever o perfil e a evolução das intoxicações no município de Feira de Santana, Bahia, nos anos 2007 a 2010, e analisar a morbimortalidade causada por medicamentos. Neste estudo transversal, com caráter descritivo, foram analisados 631 casos registrados no SINAN. As variáveis utilizadas foram: sexo; faixa etária; raça; escolaridade; ocupação; evolução do caso notificado; zona de ocorrência da intoxicação; circunstância determinante para a ocorrência da intoxicação; tipo de exposição; frequência deste agravo; e tipo de unidade notificadora. Constatou-se que a intoxicação por medicamentos representou 33% das intoxicações, seguida de “raticidas” (18%, sendo a “tentativa de suicídio”, circunstância responsável, em 2010, por 81% das notificações. O sexo ‘feminino’ apresentou o maior número de casos registrados, bem como as crianças de 1 a 4 anos e os adultos jovens. A letalidade observada em Feira de Santana foi muito maior do que a média regional e nacional, excetuando-se o ano de 2009. A Vigilância em Saúde deve priorizar ações educativas, preventivas e intersetoriais, que assegurem o uso correto de medicamentos e melhorem seu impacto na saúde, bem como investir na sensibilização continuada dos profissionais da Atenção Básica para melhorar a notificação deste importante agravo.

An AFM and XPS study of corrosion caused by micro-liquid of dilute sulfuric acid on stainless steel

International Nuclear Information System (INIS)

Wang Rongguang

2004-01-01

Micro-liquid of dilute sulfuric acid deposited on SUS304 steel surface were observed with the ac non-contact mode of an atomic force microscopy (AFM), and the detail of the corrosion process caused by them was investigated with the contact mode of the AFM, X-ray photoelectron spectroscopy (XPS) and wavelength dispersive X-ray spectroscopy (WDXS). As a result, even not applying bias voltages between the tip of the cantilever and the specimen, micro-liquid of sulfuric acid can be successfully imaged using the ac non-contact mode of AFM. Two shapes of micro-acid, i.e., micro-droplets and micro-films, were found to co-exist on the specimen surface. On areas covered by micro-films of acid, only small corrosion product particles appeared and no corrosion pits were found. Beneath micro-droplets, corrosion reaction continue to produce pits until they were all consumed to form a corrosion product (mainly iron oxides) with almost the same shape with the droplet. The total corrosion reaction time was speculated to be between 690 and 1500 ks. The corrosion product formed from micro-droplets was believed to be a process of accumulating small corrosion product particles from the liquid/substrate interface to the surface of the formerly produced corrosion product. The XPS and WDXS analysis also supports the above results

Infecções por vírus respiratórios em lactentes com suspeita clínica de coqueluche

Directory of Open Access Journals (Sweden)

Angela E. Ferronato

2013-12-01

Full Text Available OBJETIVO: avaliar a frequência das infecções por vírus respiratórios em lactentes hospitalizados com suspeita clínica de coqueluche e analisar suas características admissionais e evolutivas. MÉODOS: foi realizado um estudo de coorte histórica, em um serviço sentinela para coqueluche, no qual a pesquisa de vírus respiratórios também foi rotineira para os lactentes hospitalizados com problemas respiratórios. Foram incluídos todos os lactentes submetidos à notificação compulsória de suspeita de coqueluche. Foram realizadas pesquisas para Bordetela pertussis - BP (PCR/cultura e vírus respiratórios - VR (imunofluorescência. Foram excluídos os pacientes que haviam recebido macrolídeos previamente à internação. Os dados clínicos foram obtidos dos prontuários. RESULTADOS: dentre os 67 pacientes analisados, a pesquisa para BP foi positiva em 44% e para VR em 26%. Não houve identificação etiológica em 35% e em 5% houve codetecção de VR e BP. Todos os pacientes apresentaram características demográficas semelhantes. A presença de tosse seguida de guincho inspiratório ou cianose foi um forte preditor de coqueluche, assim como, leucocitose e linfocitose evidentes. Coriza e dispneia foram mais frequentes nas infecções virais. Houve suspensão do uso de macrolídeos em 40% dos pacientes com pesquisa positiva para VR e negativa para BP. CONCLUSÃO: os resultados sugerem que lactentes hospitalizados com suspeita de coqueluche podem apresentar infecção viral e a pesquisa etiológica pode possibilitar a redução do uso de macrolídeos em alguns casos. No entanto, salienta-se que o diagnóstico etiológico de infecção por vírus respiratórios, por si só, não exclui a possibilidade de infecção por Bordetella pertussis.

The influence of oxygen adsorption on the NEXAFS and core-level XPS spectra of the C60 derivative PCBM

International Nuclear Information System (INIS)

Brumboiu, Iulia Emilia; Eriksson, Olle; Brena, Barbara; Ericsson, Leif; Hansson, Rickard; Moons, Ellen

2015-01-01

Fullerenes have been a main focus of scientific research since their discovery due to the interesting possible applications in various fields like organic photovoltaics (OPVs). In particular, the derivative [6,6]-phenyl-C 60 -butyric acid methyl ester (PCBM) is currently one of the most popular choices due to its higher solubility in organic solvents compared to unsubstituted C 60 . One of the central issues in the field of OPVs is device stability, since modules undergo deterioration (losses in efficiency, open circuit voltage, and short circuit current) during operation. In the case of fullerenes, several possibilities have been proposed, including dimerization, oxidation, and impurity related deterioration. We have studied by means of density functional theory the possibility of oxygen adsorption on the C 60 molecular moiety of PCBM. The aim is to provide guidelines for near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) measurements which can probe the presence of atomic or molecular oxygen on the fullerene cage. By analysing several configurations of PCBM with one or more adsorbed oxygen atoms, we show that a joint core level XPS and O1s NEXAFS investigation could be effectively used not only to confirm oxygen adsorption but also to pinpoint the bonding configuration and the nature of the adsorbate

XPS Spectra Analysis of Ti2+, Ti3+ Ions and Dye Photodegradation Evaluation of Titania-Silica Mixed Oxide Nanoparticles

Science.gov (United States)

Chinh, Vu Duc; Broggi, Alessandra; Di Palma, Luca; Scarsella, Marco; Speranza, Giorgio; Vilardi, Giorgio; Thang, Pham Nam

2018-04-01

TiO2-SiO2 mixed oxides have been prepared by the sol-gel technique from tetrabutyl orthotitanate and tetraethyl orthosilicate. The prepared materials were characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, nitrogen physisorption, Fourier-transform infrared spectroscopy (FT-IR) and x-ray photoelectron spectroscopy (XPS). The results indicate that the TiO2-SiO2 mixed oxides have a large surface area and a nanoscale size. FT-IR spectra show that Ti atoms are bonded to silica by oxygen bridging atoms in Ti-O-Si bonds. The titanium valence states in TiO2-SiO2 mixed oxides were investigated by XPS, and their spectra report the presence of Ti2+ and Ti3+ cations for high silica concentration, suggesting the formation of oxygen vacancies. The photocatalytic activity of the prepared materials has been evaluated for the photodegradation of methylene blue (MB). The mixed oxides were activated by means of a UV light source, and the concentration of MB was monitored by UV-Vis spectroscopy. The synthesized TiO2-SiO2 shows significantly higher MB removal efficiency in comparison with that of the commercial TiO2 Degussa, P25.

Percepção de segurança no bairro e tempo despendido em frente à tela por adolescentes de Curitiba, Brasil

Directory of Open Access Journals (Sweden)

Crisley Vanessa Prado

Full Text Available RESUMO: Objetivo: Analisar a associação entre a percepção de segurança (PS no bairro e o tempo despendido em frente à tela pelos adolescentes e verificar o papel moderador das variáveis sexo, idade e nível socioeconômico nessa relação. Métodos: Trata-se de um estudo transversal, com inquérito escolar realizado em Curitiba, Paraná. Inicialmente foram selecionadas, de modo intencional, seis escolas (três públicas e três privadas, e em seguida foi sorteada uma turma de cada período de ensino (sexto ano do ensino fundamental ao terceiro ano do ensino médio. A PS foi avaliada com a escala NEWS-Y, e o tempo diário despendido em frente à tela foi definido por aquele passado diante da televisão/vídeo/DVD, jogando videogame e utilizando a internet. Modelos de regressão logística multinomial foram utilizados para testar a associação entre a PS e essa atividade, ajustando para as variáveis moderadoras. Resultados: Participaram do estudo 776 adolescentes, com idade entre 11 e 18 anos. A PS relacionada aos crimes foi associada com o uso de videogame por adolescentes mais velhos, no sentido contrário ao esperado (p < 0,05. A PS relacionada ao tráfego de pedestres foi associada inversamente ao uso de videogame por adolescentes de maior nível socioeconômico (p < 0,05. Conclusão: A associação entre PS e tempo despendido em frente à tela é complexa para os adolescentes e difere em relação às variáveis sociodemográficas e o desfecho analisado (televisão/vídeo/DVD, videogame e internet.

Cuidado paliativo e enfermeiros de terapia intensiva: sentimentos que ficam

OpenAIRE

Silveira, Natyele Rippel; Nascimento, Eliane Regina Pereira do; Rosa, Luciana Martins da; Jung, Walnice; Martins, Sabrina Regina; Fontes, Moisés dos Santos

2016-01-01

RESUMO Objetivo: conhecer os sentimentos dos enfermeiros acerca dos cuidados paliativos em unidades de terapia intensiva de adultos. Método: estudo qualitativo, cujo referencial teórico adotado foi o das Representações Sociais, realizado com 30 enfermeiros do estado de Santa Catarina incluídos por amostragem Bola de Neve. Os dados foram coletados por meio de entrevistas semiestruturadas realizadas de abril a agosto de 2015, organizados e analisados por meio do Discurso do Sujeito Coletivo. ...

New insights into micro/nanoscale combined probes (nanoAuger, μXPS) to characterize Ag/Au@SiO2 core-shell assemblies

Science.gov (United States)

Ledeuil, J. B.; Uhart, A.; Soulé, S.; Allouche, J.; Dupin, J. C.; Martinez, H.

2014-09-01

This work has examined the elemental distribution and local morphology at the nanoscale of core@shell Ag/Au@SiO2 particles. The characterization of such complex metal/insulator materials becomes more efficient when using an initial cross-section method of preparation of the core@shell nanoparticles (ion milling cross polisher). The originality of this route of preparation allows one to obtain undamaged, well-defined and planar layers of cross-cut nano-objects. Once combined with high-resolution techniques of characterization (XPS, Auger and SEM), the process appears as a powerful way to minimize charging effects and enhance the outcoming electron signal (potentially affected by the topography of the material) during analysis. SEM experiments have unambiguously revealed the hollow-morphology of the metal core, while Auger spectroscopy observations showed chemical heterogeneity within the particles (as silver and gold are randomly found in the core ring). To our knowledge, this is the first time that Auger nano probe spectroscopy has been used and successfully optimized for the study of some complex metal/inorganic interfaces at such a high degree of resolution (~12 nm). Complementarily, XPS Au 4f and Ag 3d peaks were finally detected attesting the possibility of access to the whole chemistry of such nanostructured assemblies.This work has examined the elemental distribution and local morphology at the nanoscale of core@shell Ag/Au@SiO2 particles. The characterization of such complex metal/insulator materials becomes more efficient when using an initial cross-section method of preparation of the core@shell nanoparticles (ion milling cross polisher). The originality of this route of preparation allows one to obtain undamaged, well-defined and planar layers of cross-cut nano-objects. Once combined with high-resolution techniques of characterization (XPS, Auger and SEM), the process appears as a powerful way to minimize charging effects and enhance the outcoming

XPS and NRA investigations during the fabrication of gold nanostructured functionalized screen-printed sensors for the detection of metallic pollutants

Energy Technology Data Exchange (ETDEWEB)

Jasmin, Jean-Philippe [Laboratoire Analyse et Modélisation pour la Biologie et l’Environnement, UMR 8587, CNRS-Université Evry Val d’Essonne-CEA, 1 rue du père Jarlan, 91025 Evry Cedex (France); Miserque, Frédéric [Den-Service de la Corrosion et du Comportement des Matériaux dans leur Environnement (SCCME), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Dumas, Eddy [Institut Lavoisier de Versailles, UMR 8180, CNRS-Université de Versailles Saint-Quentin-en-Yvelines, 78035 Versailles (France); Vickridge, Ian; Ganem, Jean-Jacques [INSP, UMR 7588, CNRS- Université Pierre et Marie Curie, 4 place Jussieu, boîte courrier 840 75252 Paris, Cedex 05 (France); Cannizzo, Caroline, E-mail: caroline.cannizzo@univ-evry.fr [Laboratoire Analyse et Modélisation pour la Biologie et l’Environnement, UMR 8587, CNRS-Université Evry Val d’Essonne-CEA, 1 rue du père Jarlan, 91025 Evry Cedex (France); Chaussé, Annie [Laboratoire Analyse et Modélisation pour la Biologie et l’Environnement, UMR 8587, CNRS-Université Evry Val d’Essonne-CEA, 1 rue du père Jarlan, 91025 Evry Cedex (France)

2017-03-01

Highlights: • Functionalized nanostructured SPEs were made by multi-step diazonium salt chemistry. • Investigation of SPEs surface by XPS and NRA shows monolayer coverage by aminobenzyl groups. • Complete conversion of aminobenzyl groups into diazonium functions was also evidenced. • Covalent grafting of AuNPs onto SPEs lead to an unusual modification of Au-4f core level spectrum. • Ligand and lead signals showed the interest of nanostructurated SPEs for trace metals detection. - Abstract: An all covalent nanostructured lead sensor was built by the successive grafting of gold nanoparticles and carboxylic ligands at the surface of self-adhesive carbon screen-printed electrodes (SPEs). Surface analysis techniques were used in each step in order to investigate the structuration of this sensor. The self-adhesive surfaces were made from the electrochemical grafting of p-phenylenediamine at the surface of the SPEs via diazonium salts chemistry. The quantity of grafted aniline functions, estimated by Nuclear Reaction Analysis (NRA) performed with p-phenylenediamine labelled with {sup 15}N isotope, is in agreement with an almost complete coverage of the electrode surface. The subsequent diazotization of the aniline functions at the surface of the SPEs was performed; X-ray Photoelectron Spectroscopy (XPS) allowed us to consider a quantitative conversion of the aniline functions into diazonium moieties. The spontaneous grafting of gold nanoparticles on the as-obtained reactive surfaces ensures the nanostructuration of the material, and XPS studies showed that the covalent bonding of the gold nanoparticles at the surface of the SPEs induces a change both in the Au-4f (gold nanoparticles) and Cl-2p (carbon ink) core level signals. These unusual observations are explained by an interaction between the carbon ink constituting the substrate and the gold nanoparticles. Heavy and toxic metals are considered of major environmental concern because of their non

XPS and NRA investigations during the fabrication of gold nanostructured functionalized screen-printed sensors for the detection of metallic pollutants

International Nuclear Information System (INIS)

Jasmin, Jean-Philippe; Miserque, Frédéric; Dumas, Eddy; Vickridge, Ian; Ganem, Jean-Jacques; Cannizzo, Caroline; Chaussé, Annie

2017-01-01

Highlights: • Functionalized nanostructured SPEs were made by multi-step diazonium salt chemistry. • Investigation of SPEs surface by XPS and NRA shows monolayer coverage by aminobenzyl groups. • Complete conversion of aminobenzyl groups into diazonium functions was also evidenced. • Covalent grafting of AuNPs onto SPEs lead to an unusual modification of Au-4f core level spectrum. • Ligand and lead signals showed the interest of nanostructurated SPEs for trace metals detection. - Abstract: An all covalent nanostructured lead sensor was built by the successive grafting of gold nanoparticles and carboxylic ligands at the surface of self-adhesive carbon screen-printed electrodes (SPEs). Surface analysis techniques were used in each step in order to investigate the structuration of this sensor. The self-adhesive surfaces were made from the electrochemical grafting of p-phenylenediamine at the surface of the SPEs via diazonium salts chemistry. The quantity of grafted aniline functions, estimated by Nuclear Reaction Analysis (NRA) performed with p-phenylenediamine labelled with "1"5N isotope, is in agreement with an almost complete coverage of the electrode surface. The subsequent diazotization of the aniline functions at the surface of the SPEs was performed; X-ray Photoelectron Spectroscopy (XPS) allowed us to consider a quantitative conversion of the aniline functions into diazonium moieties. The spontaneous grafting of gold nanoparticles on the as-obtained reactive surfaces ensures the nanostructuration of the material, and XPS studies showed that the covalent bonding of the gold nanoparticles at the surface of the SPEs induces a change both in the Au-4f (gold nanoparticles) and Cl-2p (carbon ink) core level signals. These unusual observations are explained by an interaction between the carbon ink constituting the substrate and the gold nanoparticles. Heavy and toxic metals are considered of major environmental concern because of their non

XPS studies of SiO2 surface layers formed by oxygen ion implantation into silicon

International Nuclear Information System (INIS)

Schulze, D.; Finster, J.

1983-01-01

SiO 2 surface layers of 160 nm thickness formed by 16 O + ion implantation into silicon are examined by X-ray photoelectron spectroscopy measurements into the depth after a step-by-step chemical etching. The chemical nature and the thickness of the transition layer were determined. The results of the XPS measurements show that the outer surface and the bulk of the layers formed by oxygen implantation and subsequent high temperature annealing consist of SiO 2 . There is no evidence for Si or SiO/sub x/ (0 2 and Si is similar to that of thin grown oxide layers. Only its thickness is somewhat larger than in thermal oxide

Quantification of the toxic hexavalent chromium content in an organic matrix by X-ray photoelectron spectroscopy (XPS) and ultra-low-angle microtomy (ULAM)

Science.gov (United States)

Greunz, Theresia; Duchaczek, Hubert; Sagl, Raffaela; Duchoslav, Jiri; Steinberger, Roland; Strauß, Bernhard; Stifter, David

2017-02-01

Cr(VI) is known for its corrosion inhibitive properties and is, despite legal regulations, still a potential candidate to be added to thin (1-3 μm) protective coatings applied on, e.g., electrical steel as used for transformers, etc. However, Cr(VI) is harmful to the environment and to the human health. Hence, a reliable quantification of it is of decisive interest. Commonly, an alkaline extraction with a photometric endpoint detection of Cr(VI) is used for such material systems. However, this procedure requires an accurate knowledge on sample parameters such as dry film thickness and coating density that are occasionally associated with significant experimental errors. We present a comprehensive study of a coating system with a defined Cr(VI) pigment concentration applied on electrical steel. X-ray photoelectron spectroscopy (XPS) was employed to resolve the elemental chromium concentration and the chemical state. Turning to the fact that XPS is extremely surface sensitive (distribution inside the coating.

XPS investigations of ruthenium deposited onto representative inner surfaces of nuclear reactor containment buildings

Energy Technology Data Exchange (ETDEWEB)

Mun, C. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Direction de la Prevention des Accidents Majeurs (DPAM), Centre de Cadarache, BP3-13115 Saint-Paul-lez-Durance (France)]. E-mail: christian.mun@irsn.fr; Ehrhardt, J.J. [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME) UMR 7564, CNRS-Nancy University-405, rue de Vandoeuvre 54600 Villers-les-Nancy (France)]. E-mail: ehrhardt@lcpe.cnrs-nancy.fr; Lambert, J. [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME) UMR 7564, CNRS-Nancy University-405, rue de Vandoeuvre 54600 Villers-les-Nancy (France); Madic, C. [Commissariat a l' Energie Atomique (CEA), Direction de l' Energie Nucleaire, Centre de Saclay, 91191 Gif-sur-Yvette Cedex (France)]. E-mail: charles.madic@cea.fr

2007-07-15

In the case of a hypothetical severe accident in a nuclear power plant, interactions of gaseous RuO{sub 4} with reactor containment building surfaces (stainless steel and epoxy paint) could possibly lead to a black Ru-containing deposit on these surfaces. Some scenarios include the possibility of formation of highly radiotoxic RuO{sub 4}(g) by the interactions of these deposits with the oxidizing medium induced by air radiolysis, in the reactor containment building, and consequently dispersion of this species. Therefore, the accurate determination of the chemical nature of ruthenium in the deposits is of the high importance for safety studies. An experiment was designed to model the interactions of RuO{sub 4}(g) with samples of stainless steel and of steel covered with epoxy paint. Then, these deposits have been carefully characterised by scanning electron microscopy (SEM/EDS), electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). The analysis by XPS of Ru deposits formed by interaction of RuO{sub 4}(g), revealed that the ruthenium is likely to be in the IV oxidation state, as the shapes of the Ru 3d core levels are very similar with those observed on the RuO{sub 2}.xH{sub 2}O reference powder sample. The analysis of O 1s peaks indicates a large component attributed to the hydroxyl functional groups. From these results, it was concluded that Ru was present on the surface of the deposits as an oxyhydroxide of Ru(IV). It has also to be pointed out that the presence of 'pure' RuO{sub 2}, or of a thin layer of RuO{sub 3} or Ru{sub 2}O{sub 5}, coming from the decomposition of RuO{sub 4} on the surface of samples of stainless steel and epoxy paint, could be ruled out. These findings will be used for further investigations of the possible revolatilisation phenomena induced by ozone.

DESAJUSTE EDUCATIVO POR REGIONES EN COLOMBIA: ¿COMPETENCIA POR SALARIOS O POR PUESTOS DE TRABAJO?

Directory of Open Access Journals (Sweden)

Maribel Castillo Caicedo

2007-06-01

Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación, entendida como un desajuste por exceso, entre el nivel educativo alcanzado por el individuo y el exigido por el puesto de trabajo en el cual se desempeña; esto se debe a que existe una demanda laboral estrecha de puestos de trabajo para personas calificadas en Colombia. Se analizan las contribuciones empíricas existentes y el debate sobre las mismas; se examinan las teorías que permiten explicar la existencia de un desajuste educativo y se realiza una revisión de la literatura internacional y nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis para desarrollar un esquema que permita determinar el comportamiento del individuo en el fenómeno de la sobreeducación.

In situ NAP-XPS spectroscopy during methane dry reforming on ZrO2/Pt(1 1 1) inverse model catalyst

Science.gov (United States)

Rameshan, C.; Li, H.; Anic, K.; Roiaz, M.; Pramhaas, V.; Rameshan, R.; Blume, R.; Hävecker, M.; Knudsen, J.; Knop-Gericke, A.; Rupprechter, G.

2018-07-01

Due to the need of sustainable energy sources, methane dry reforming is a useful reaction for conversion of the greenhouse gases CH4 and CO2 to synthesis gas (CO  +  H2). Syngas is the basis for a wide range of commodity chemicals and can be utilized for fuel production via Fischer–Tropsch synthesis. The current study focuses on spectroscopic investigations of the surface and reaction properties of a ZrO2/Pt inverse model catalyst, i.e. ZrO2 particles (islands) grown on a Pt(1 1 1) single crystal, with emphasis on in situ near ambient pressure x-ray photoelectron spectroscopy (NAP-XPS) during MDR reaction. In comparison to technological systems, model catalysts facilitate characterization of the surface (oxidation) state, surface adsorbates, and the role of the metal-support interface. Using XPS and infrared reflection absorption spectroscopy we demonstrated that under reducing conditions (UHV or CH4) the ZrO2 particles transformed to an ultrathin ZrO2 film that started to cover (wet) the Pt surface in an SMSI-like fashion, paralleled by a decrease in surface/interface oxygen. In contrast, (more oxidizing) dry reforming conditions with a 1:1 ratio of CH4 and CO2 were stabilizing the ZrO2 particles on the model catalyst surface (or were even reversing the strong metal support interaction (SMSI) effect), as revealed by in situ XPS. Carbon deposits resulting from CH4 dissociation were easily removed by CO2 or by switching to dry reforming conditions (673–873 K). Thus, at these temperatures the active Pt surface remained free of carbon deposits, also preserving the ZrO2/Pt interface.

Evaluation of process influences on surface chemistry of epoxy acrylate based solder mask via XPS, ToF-SIMS and contact angle measurement

Energy Technology Data Exchange (ETDEWEB)

Hofmeister, Caroline, E-mail: caroline.hofmeister@de.bosch.com [Robert Bosch GmbH, Postfach 30 02 40, 70442 Stuttgart (Germany); Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Str. 12, 28359 Bremen (Germany); Maaß, Sebastian [Robert Bosch GmbH, Postfach 30 02 40, 70442 Stuttgart (Germany); Fladung, Thorsten; Mayer, Bernd [Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Str. 12, 28359 Bremen (Germany)

2017-01-01

Epoxy acrylate based solder mask formulations were conditioned by different printed circuit board (PCB) manufacturing and PCB assembly process stages. Depending on these different influences the chemistry of the solder mask surface was investigated regarding adhesion to possible adhesion partners. The combination of X-ray photoelectron spectrometry (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and the contact angle method, for surface energy determination, provided a detailed understanding of the surface near region up to the topmost monolayer, which forms the contact zone in which adhesion takes place. The combination of ToF-SIMS and XPS provided molecular information of surface components comprising quantitative information. The influences of all process steps, like UV, chemical and thermal treatment, on the chemical surface composition and appearance were identified. Based on the results a chemical surface model could be created regarding the different adhesion mechanisms. It has been shown that an enrichment of siloxanes at the surface is generated by different mechanisms that were distinguished based on ToF-SIMS. Even though an oxidation process in the surface near region (10 nm) was indicated by XPS, no increase of the surface polar groups and thus no polarity increase could be observed within the first monolayer. A surface model derived from the analysis results shows generation and occupation of free sites at the surface through all stages of the process. An occupation of free sites by siloxanes from additives in the solder mask formulation results in a siloxane dominated topmost monolayer. - Highlights: • A surface model describing the process influences is proposed. • Detailed siloxane reaction analysis was possible with ToF-SIMS. • Photo-chemical, chemical and thermal surface modification occur during PCB manufacturing.

XPS and STEM study of the interface formation between ultra-thin Ru and Ir OER catalyst layers and perylene red support whiskers

Directory of Open Access Journals (Sweden)

Atanasoska Ljiljana L.

2013-01-01

Full Text Available The interface formation between nano-structured perylene red (PR whiskers and oxygen evolution reaction (OER catalysts ruthenium and iridium has been studied systematically by XPS and STEM. The OER catalyst over-layers with thicknesses ranging from ~0.1 to ~50 nm were vapor deposited onto PR ex-situ. STEM images demonstrate that, with increasing thickness, Ru and Ir transform from amorphous clusters to crystalline nanoparticles, which agglomerate with increased over-layer thickness. XPS data show a strong interaction between Ru and PR. Ir also interacts with PR although not to the extent seen for Ru. At low coverages, the entire Ru deposit is in the reacted state while a small portion of the deposited Ir remains metallic. Ru and Ir bonding occur at the PR carbonyl sites as evidenced by the attenuation of carbonyl photoemission and the emergence of new peak assigned to C-O single bond. The curve fitting analysis and the derived stoichiometry indicates the formation of metallo-organic bonds. The co-existence of oxide bonds is also apparent.

XPS-nanocharacterization of organic layers electrochemically grafted on the surface of SnO{sub 2} thin films to produce a new hybrid material coating

Energy Technology Data Exchange (ETDEWEB)

Drevet, R., E-mail: richarddrevet@yahoo.fr [Univ. Paris Sud, SP2M-ICMMO, CNRS UMR 8182, Bât. 410, 91405 Orsay Cedex (France); Université d’Evry Val d’Essonne, LAMBE, CNRS-CEA UMR 8587, Boulevard François Mitterrand, 91025 Evry Cedex (France); Dragoé, D.; Barthés-Labrousse, M.G. [Univ. Paris Sud, SP2M-ICMMO, CNRS UMR 8182, Bât. 410, 91405 Orsay Cedex (France); Chaussé, A. [Université d’Evry Val d’Essonne, LAMBE, CNRS-CEA UMR 8587, Boulevard François Mitterrand, 91025 Evry Cedex (France); Andrieux, M. [Univ. Paris Sud, SP2M-ICMMO, CNRS UMR 8182, Bât. 410, 91405 Orsay Cedex (France)

2016-10-30

Graphical abstract: An innovative hybrid material layer is synthesized by combining two processes. SnO{sub 2} thin films are deposited by MOCVD on Si substrates and an organic layer made of carboxyphenyl moieties is electrochemically grafted by the reduction of a diazonium salt. XPS characterizations are carried out to assess the efficiency of the electrochemical grafting. Display Omitted - Highlights: • An innovative hybrid material layer is synthesized by combining two processes. • SnO{sub 2} thin films are deposited by MOCVD on Si substrates. • An organic layer is electrochemically grafted by the reduction of a diazonium salt. • The efficiency of the grafting is accurately assessed by XPS. • Three electrochemical grafting models are proposed. - Abstract: This work presents the synthesis and the characterization of hybrid material thin films obtained by the combination of two processes. The electrochemical grafting of organic layers made of carboxyphenyl moieties is carried out from the reduction of a diazonium salt on tin dioxide (SnO{sub 2}) thin films previously deposited on Si substrates by metal organic chemical vapor deposition (MOCVD). Since the MOCVD experimental parameters impact the crystal growth of the SnO{sub 2} layer (i.e. its morphology and its texturation), various electrochemical grafting models can occur, producing different hybrid materials. In order to evidence the efficiency of the electrochemical grafting of the carboxyphenyl moieties, X-ray Photoelectron Spectroscopy (XPS) is used to characterize the first nanometers in depth of the synthesized hybrid material layer. Then three electrochemical grafting models are proposed.

Características tecnológicas de farinhas de arroz pré-gelatinizadas obtidas por extrusão termoplástica Technological properties of pre-gelatinized rice flour obtained by thermoplastic extrusion

Directory of Open Access Journals (Sweden)

Maria Teresa Pedrosa Silva Clerici

2008-10-01

Full Text Available A farinha de arroz tem sido um ingrediente atrativo para a indústria de extrusados, devido à suas qualidades como sabor suave, cor branca e hipoalergenicidade. Objetivou-se, neste trabalho, produzir e analisar farinha de arroz pré-gelatinizada (FPG por extrusão termoplástica. As FPG foram produzidas num extrusor termoplástico monorosca Brabender, variando-se a umidade (19,2 a 24,8% e a temperatura de extrusão (108 a 192ºC. As características de torque, índice de expansão, propriedades viscoamilográficas, índice de absorção em água (IAA e índice de solubilidade em água (ISA das FPG foram analisadas por metodologia de superfície de resposta (MRS e análise de componentes principais (ACP. Os resultados analisados por MRS e ACP indicaram que o torque e o índice de expansão dos extrusados apresentaram os maiores valores quando foram usados os menores teores de umidade. As FPG apresentaram, dentro das propriedades viscoamilográficas, a viscosidade inicial de pasta maior em temperaturas mais altas, já a viscosidade a 95ºC e a 50ºC foram maiores quando temperatura e umidade estavam em extremos opostos. O IAA foi menor quando se usaram baixas temperaturas e maiores teores de umidades; no entanto, o ISA, quando analisado pela MRS, não apresentou influência da temperatura e umidade, mas quando analisado pela ACP, foi maior quando as temperaturas estavam entre 120 - 150ºC e os teores de umidade entre 19,2 e 22%. Concluindo, as análises de MRS e de ACP mostraram que a variação das propriedades tecnológicas das FPG foram relacionadas aos extremos de temperatura e/ou umidade utilizados durante o processo de extrusão, e a ACP foi capaz de complementar a análise feita através da MRS.The rice flour has become an attractive ingredient in the extrusion industry due to its unique attributes such as bland taste, white color and hypoallergenicity. The purpose of this research was to produce and analyze pre-gelatinized rice flour (GRF

Desajuste educativo por regiones en Colombia: ¿competencia por salarios o por puestos de trabajo?

Directory of Open Access Journals (Sweden)

Castillo Caicedo Maribel

2007-08-01

Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación,
entendida como un desajuste por exceso, entre el nivel educativo alcanzado
por el individuo y el exigido por el puesto de trabajo en el cual se
desempeña; esto se debe a que existe una demanda laboral estrecha de
puestos de trabajo para personas calificadas en Colombia. Se analizan las
contribuciones empíricas existentes y el debate sobre las mismas; se
examinan las teorías que permiten explicar la existencia de un desajuste
educativo y se realiza una revisión de la literatura internacional y
nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis
para desarrollar un esquema que permita determinar el comportamiento
del individuo en el fenómeno de la sobreeducación.

Perda e luto: vivências de mulheres que interromperam a gestação por malformação fetal letal

Directory of Open Access Journals (Sweden)

Elenice Bertanha Consonni

2013-09-01

Full Text Available O presente estudo teve por objetivo conhecer as vivências de luto de mulheres que interromperam a gestação sob autorização judicial, devido à malformação fetal incompatível com a vida. Participaram do estudo dez mulheres atendidas no Setor de Medicina Fetal do Hospital das Clínicas de Botucatu. Para coleta dos dados foi realizada entrevista semiestruturada quarenta dias após a interrupção. As entrevistas foram audiogravadas, transcritas na íntegra e tiveram os dados analisados na perspectiva da análise temática de conteúdo. Os resultados revelaram que as mães buscaram explicações e significados para a perda, sendo muito frequentes respostas religiosas e autoculpabilizantes. Os relatos marcaram sentimentos de tristeza, saudade e sensação de vazio pela perda do filho, revelando também a necessidade das mães de manterem-se ligadas a ele. As mães estavam e continuaram vinculadas aos seus filhos e a interrupção da gestação, embora tenha sido uma escolha para minimizar a dor de uma perda inevitável, não as poupou de vivências de grande sofrimento. O estudo traz subsídios para a discussão e planejamento de abordagens e cuidados com a saúde de mulheres que interrompem a gestação por malformação fetal letal, mediante autorização judicial.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

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Dhana G Gorasia

2016-08-01

Full Text Available The type IX secretion system (T9SS has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

Science.gov (United States)

Gorasia, Dhana G; Veith, Paul D; Hanssen, Eric G; Glew, Michelle D; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C

2016-08-01

The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

The PorX response regulator of the Porphyromonas gingivalis PorXY two-component system does not directly regulate the Type IX secretion genes but binds the PorL subunit.

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Maxence S Vincent

2016-08-01

Full Text Available The Type IX secretion system (T9SS is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion of surface attachment of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY and PorX encode typical two-component system (TCS sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of the porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we showed that PorX does not bind and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

Demandas judiciais por medicamentos antineoplásicos: a ponta de um iceberg?

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Thaís Jeronimo Vidal

Full Text Available Resumo Ações judiciais com medicamentos antineoplásicos geram custos elevados aos governos e demandam análises criteriosas para garantir resultados eficientes e adequados em saúde. Este trabalho analisou processos enviados por entes federados a um instituto referência no tratamento de câncer para emissão de parecer técnico. Coletou-se dados das cópias dos processos analisados entre julho e dezembro/2013 e avaliou-se: subgrupos terapêuticos, presença em lista de medicamentos essenciais, registro sanitário, indicação off label, indicações constantes em diretrizes clínicas, incorporação do medicamento no sistema público de saúde e valor estimado das causas. Foram examinados 158 processos, com 164 solicitações de 35 antineoplásicos. A maioria dos medicamentos eram inibidores da tirosinoquinase, dez figuravam em lista de medicamentos essenciais, três não continham registro sanitário, dez tinham indicação de uso off label, 56,7% estavam descritas em diretrizes clínicas, quatro tinham recomendação para incorporação e o valor estimado das causas foi de R$ 18.110.504,89. Identificou-se que os instrumentos técnico-sanitários disponíveis para subsidiar as decisões parecem ser insuficientes e que há a necessidade de se estabelecer estratégias para minimizar o comprometimento da integralidade do cuidado.

Quantitative chemical state XPS analysis of first row transition metals, oxides and hydroxides

International Nuclear Information System (INIS)

Biesinger, M C; Payne, B P; McIntryre, N S; Hart, B R; Lau, L Wm; Grosvenor, A P; Smart, R StC

2008-01-01

Practical quantitative chemical state X-ray photoelectron spectroscopy (XPS) analysis of first row transition metals, oxides and hydroxides is challenging due to the complexity of their M 2p spectra. Complex multiplet splitting, shake-up and plasmon loss structure can play a role in the interpretation of the chemical states present. This paper will show practical curve fitting procedures for the quantitative measurement of different chemical states for metal oxides and hydroxides from a survey of transition metals. It will also discuss some of the limitations and pitfalls present as well as give practical examples of their successful use. These curve-fitting procedures are based on 1) standard spectra from quality reference samples, 2) a survey of appropriate literature databases and/or a compilation of literature references, 3) fitting of multiplet split spectra based on spectra of numerous reference materials and theoretical modelling, 4) spectral subtractions routines, again using reference spectra, and 5) specific literature references where fitting procedures are available

Quantitative chemical state XPS analysis of first row transition metals, oxides and hydroxides

Energy Technology Data Exchange (ETDEWEB)

Biesinger, M C; Payne, B P; McIntryre, N S [Department of Chemistry, University of Western Ontario, London, Ontario, N6A 5B7 (Canada); Hart, B R; Lau, L Wm [Surface Science Western, Room G1, Western Science Centre, University of Western Ontario, London, Ontario, N6A 5B7 (Canada); Grosvenor, A P [Department of Chemistry, Gunning/Lemieux Chemistry Centre, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada); Smart, R StC [ACeSSS, Applied Centre for Structural and Synchrotron Studies, University of South Australia, Mawson Lakes, SA 5095 (Australia)], E-mail: biesingr@uwo.ca

2008-03-15

Practical quantitative chemical state X-ray photoelectron spectroscopy (XPS) analysis of first row transition metals, oxides and hydroxides is challenging due to the complexity of their M 2p spectra. Complex multiplet splitting, shake-up and plasmon loss structure can play a role in the interpretation of the chemical states present. This paper will show practical curve fitting procedures for the quantitative measurement of different chemical states for metal oxides and hydroxides from a survey of transition metals. It will also discuss some of the limitations and pitfalls present as well as give practical examples of their successful use. These curve-fitting procedures are based on 1) standard spectra from quality reference samples, 2) a survey of appropriate literature databases and/or a compilation of literature references, 3) fitting of multiplet split spectra based on spectra of numerous reference materials and theoretical modelling, 4) spectral subtractions routines, again using reference spectra, and 5) specific literature references where fitting procedures are available.

The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit

Science.gov (United States)

Vincent, Maxence S.; Durand, Eric; Cascales, Eric

2016-01-01

The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS. PMID:27630829

Identification of the silver state in the framework of Ag-containing zeolite by XRD, FTIR, photoluminescence, 109Ag NMR, EPR, DR UV-vis, TEM and XPS investigations.

Science.gov (United States)

Popovych, Nataliia; Kyriienko, Pavlo; Soloviev, Sergiy; Baran, Rafal; Millot, Yannick; Dzwigaj, Stanislaw

2016-10-26

Silver has been identified in the framework of Ag x SiBEA zeolites (where x = 3-6 Ag wt%) by the combined use of XRD, 109 Ag MAS NMR, FTIR, diffuse reflectance UV-visible, EPR and XPS spectroscopy. The incorporation of Ag ions into the framework of SiBEA zeolite has been evidenced by XRD. The consumption of OH groups as a result of their reaction with the silver precursor has been monitored by FTIR and photoluminescence spectroscopy. The changes in the silver state as a function of Ag content and thermal and hydrogen treatment at 573 K have been identified by 109 Ag MAS NMR, EPR, DR UV-visible, TEM and XPS investigations. The acidity of AgSiBEA has been investigated by FTIR spectroscopy of adsorbed CO and pyridine used as probe molecules.

Partos domiciliares planejados assistidos por enfermeiras obstétricas: transferências maternas e neonatais Partos domiciliarios planificados atendidos por enfermeras obstétricas: traslados maternales y neonatales Planned home births assisted by nurse midwives: maternal and neonatal transfers

Directory of Open Access Journals (Sweden)

Joyce Green Koettker

2013-02-01

Full Text Available O presente trabalho trata-se de estudo exploratório-descritivo que teve como objetivo descrever a taxa e as causas de transferência intraparto para o hospital de mulheres assistidas no domicílio por enfermeiras obstétricas e os desfechos desses nascimentos. A amostra foi composta por onze mulheres e seus recém-nascidos, de janeiro de 2005 a dezembro de 2009. Os dados foram coleta-dos em prontuários e cadernetas de saúde e analisados por estatística descritiva. A taxa de transferência foi de 11%, a maioria de nulíparas (63,6%, e todas foram transferidas durante o primeiro período clínico do parto. Os motivos mais frequentes de transferência foram parada de dilatação cervical e progressão da apresentação fetal, e desproporção cefalopélvica. Os escores de Apgar no 1º e 5º minutos foram >7 em 81,8% dos casos e não houve internação em unidade de terapia intensiva neonatal. Neste estudo constatou-se que o parto domiciliar planejado assistido por enfermeiras obstétricas, com protocolo assistencial, apresentou bons resultados maternos e neonatais, mesmo quando a transferência para o hospital foi necessária.Estudio exploratorio descriptivo que objetivó describir la tasa y causas de traslados hospitalarios intraparto a mujeres atendidas en domicilio por enfermeras obstétricas y los desenlaces de tales nacimientos. Muestra compuesta por once mujeres y sus recién nacidos, de enero 2005 a diciembre 2009; datos recolectados a partir de historia clínicas y carpetas de salud, analizadas por estadística descriptiva. La tasa de traslado fue 11,0%, mayoritariamente de nulíparas (63,3%, todas ellas trasladadas durante el primer período clínico del parto. Los motivos más frecuentes obedecieron a interrupción de dilatación cervical, progresión de presentación fetal y desproporción cefalopélvica. Los puntajes de Apgar en minutos 1 y 5 fueron >7 en 81,8% de los casos, no produciéndose internación en unidad de terapia

Mortalidade por raça/cor: evidências de desigualdades sociais em Vitória (ES, Brasil Mortality by race/color: evidence of social inequalities in Vitória (ES, Brazil

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Nathalia Modenesi Fiorio

2011-09-01

Full Text Available OBJETIVO: Analisar a mortalidade por causa básica, sexo e raça/cor a partir do sistema de informações sobre mortalidade (SIM, em Vitória (ES, no período de 2003 a 2006. MÉTODOS: Foram calculados e analisados os coeficientes de mortalidade, segundo causa básica e sexo por raça/cor, bem como a idade média e mediana de óbito por causa básica, sexo e raça/cor. Foi calculado o risco relativo (RR por sexo, idade e causa básica (pOBJECTIVE: To analyze mortality by cause and sex among groups of race or color from the mortality information system (MIS in Vitória (Brazil, in the period from 2003 to 2006. METHODS: We calculated and analyzed the mortality rates according to underlying cause, sex and race/color, and the mean and median age of death by underlying cause, sex and race. We calculated the relative risk (RR for age, sex and underlying cause (p<0.05 and CI 95%. RESULTS: The completeness of race/color in SIM ranged from 1% in 1996 to 81% in 2006. There was a greater RR of death among blacks for mental and behavioral disorders (RR=9.29, Ill-defined causes (RR=8.71, and external causes (RR=5.71. For black women, we highlight the external causes (RR=2.38. We found a variation of up to 33 years (nervous system between whites and blacks. CONCLUSION: This study confirms the existence of unequal racial/ethnic mortality, highlighting the mortality from mental disorders and external causes, in addition to early mortality that occurs in the black population.

Extended study on oxidation behaviors of UN0.68 and UN1.66 by XPS

Science.gov (United States)

Luo, Lizhu; Hu, Yin; Pan, Qifa; Long, Zhong; Lu, Lei; Liu, Kezhao; Wang, Xiaolin

2018-04-01

The surface oxidation behaviors of UN0.68 and UN1.66 thin films are investigated by X-ray photoelectron spectroscopy (XPS), and the traditional U4f/N1s, O1s, valence band spectra as well as the unconventional U4d and U5d spectra are collected for the understanding of their oxidation behavior in-depth. Similar asymmetrical peak shape of the U4f spectra to uranium is observed for both uranium nitrides, despite of a slight shift to higher energy side for UN1.66 clean surface. However, significant difference among the corresponding spectra of UN0.68 and UN1.66 during oxidation reveals the distinctive properties of each own. The coexistence of UO2-x, UO2 and UO2-x.Ny on UN0.68 surface results in the peculiar features of U4f spectra as well as the others within the XPS energy scale, where peaks of the oxidized species firstly shift to higher energy side compared to the clean surface, and then return closely towards those of stoichiometric UO2. For UN1.66, the generation of U-N-O ternary compounds on the surface is identified with the symmetrical U4f peaks at 379.9eV and 390.8 eV, which locate intermediate between UO2 and UN1.66, and gradually expanding to higher energy side during the progressive oxidation. Furthermore, the formation of N-O species on UN1.66 surface is also detected as an oxidation product. The metallic character of UN1.66 is identified by the intense signal at Fermi level, which is greatly suppressed by the increasing oxygen exposure and implies the weakening metallic properties of the as-generated U-N-O compounds. Higher uranium oxides, such as UO3 and U4O9, are deduced to be the final oxidation products, and a multistage mechanism for UN1.66 following the exposure to oxygen is discussed.

The 4s- and 4p- XPS spectra of Xe, XeF2 and XeF4

International Nuclear Information System (INIS)

Ohno, Masahide

2003-01-01

The 4s- and 4p- XPS spectra of Xe gas, XeF 2 molecule and XeF 4 molecule are calculated by an ab-initio atomic many-body theory. The 4s-peak and the prominent '4p'-peak are predicted well by the present theory. In XeF 2 and XeF 4 the spectral lines observed below the 4d-double ionization threshold are the 4d -2 4f multiplet states strongly perturbed by the interaction with the initial 4p 1/2 -hole state. They are very similar to the spectral lines which emerge with an increase in atomic number (e.g. Ba)

Investigation of the CANLUB/sheath interface in CANDU fuel at extended burnup by XPS and SEM/WDX

International Nuclear Information System (INIS)

Hocking, W.H.; Behnke, R.; Duclos, A.M.; Gerwing, A.F.; Chan, P.K.

1997-01-01

A systematic investigation of the fuel-sheath interface in CANDU fuel as a function of extended burnup has been undertaken by XPS and SEM/WDX analysis. Adherent deposits of UO 2 and fission products, including Cs, Ba, Rb, I, Te, Cd and possibly Ru, have been routinely identified on CANLUB coated and bare Zircaloy surfaces. Some trends in the distribution and chemistry of key fission products have begun to emerge. Several potential mechanisms for degradation of the CANLUB graphite layer at high burnup have been practically excluded. New evidence of carbon relocation within the fuel element and limited reaction with excess oxygen has also been obtained. (author)

XPS study on the surface reaction of uranium metal in H2 and H2-CO atmospheres

International Nuclear Information System (INIS)

Wang Xiaolin; Fu Yibei; Xie Renshou

1996-04-01

The surface reactions of uranium metal in H 2 and H 2 -CO atmospheres and the effects of temperature and CO on the hydriding reaction have been studied by X-ray photoelectron spectroscopy (XPS). The reaction between commercial H 2 and uranium metal at 25 degree C leads mainly to the further oxidation of surface layer of metal due to traces of water vapour. At 200 degree C, it may lead to the hydriding reaction of uranium and the hydriding increases with increasing the exposure of H 2 . Investigation indicates CO inhibits both the hydriding reaction and oxidation on the condition of H 2 -CO atmospheres. (13 refs., 10 figs.)

Depth profile analysis of polymerized fluorine compound on photo-resist film with angle-resolved XPS

International Nuclear Information System (INIS)

Iijima, Yoshitoki; Kubota, Toshio; Oinaka, Syuhei

2013-01-01

Angle-resolved XPS (ARXPS) is an observation technique which is very effective in chemical depth analysis method less than photoelectron detected depth. For the analysis of depth profile, several analysis methods have been proposed to calculate the depth profile using the ARXPS method. The present report is the measurements of depth profile of the fluorine in a fluorine-containing photo-resist film using the ARXPS method and the depth profile of concentration have been successfully determined using the ARCtick 1.0 software. It has been observed that thickness of the fluorocarbon enriched surface layer of the photo-resist was 2.7 nm, and so that the convert of the ARXPS data from the angle profile to the depth profile was proved to be useful analysis method for the ultrathin layer depth. (author)

Desenvolvimento corporal e testicular em machos de codornas de corte e de postura de 25 a 360 dias

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Tatiana C. Santos

2012-11-01

Full Text Available Codornas do tipo carne e tipo ovos foram analisadas para determinar o desenvolvimento reprodutivo, a puberdade e o início da senilidade. Para tal, 288 codornas (144 codornas de corte e 144 de postura foram acompanhadas desde a eclosão até os 360 dias de idade. As aves foram distribuídas por idade em 18 grupos, sendo 8 codornas/grupo/tipo de codorna. Após 35 dias as codornas foram mantidas em condições de fotoperíodo de dias longos (17luz: 7escuro. O peso vivo e os valores morfométricos e histológicos testiculares foram determinados em cada período. Os dados obtidos foram analisados para determinar a curva de crescimento e o comportamento dos parâmetros analisados. O modelo que mais se adequou aos dados foi o modelo não linear de Gompertz (Y=A exp [-B e (-kt]. O peso vivo e as características testiculares macro e microscópicas apresentaram comportamento alométrico entre si, sendo que, aproximadamente aos 60 dias os machos apresentaram-se sexualmente desenvolvidos, e estabilizaram o peso corporal por volta dos 100 dias. O testículo direito é mais cranial que o esquerdo e diferem em relação a comprimento e largura, porém não foi observada diferenças (P>0,05 para peso testicular. As codornas de corte apresentaram peso corporal e peso testicular maiores que as codornas de postura, porém as codornas de postura apresentaram peso relativo testicular maior. Durante todo o período analisado os machos puderam ser considerados sexualmente aptos. Os reprodutores apresentaram características sexuais ativas até os 360 dias de idade, representadas pelo tamanho testicular e pela atividade celular nos túbulos seminíferos.

XPS study of the Ln 5p,4f-electronic states of lanthanides in Ln2O3

International Nuclear Information System (INIS)

Teterin, Yu.A.; Teterin, A.Yu.; Utkin, I.O.; Ryzhkov, M.V.

2004-01-01

The present work analyses the fine structure of the low binding energy (E b , 0-50 eV) X-ray photoelectron spectra XPS of lanthanide (La through Lu excepted for Pm) oxides, and compares it with the non-relativistic X α -discrete variation calculation results for the clusters reflecting the close environment of lanthanides in oxides. The obtained results show that the Ln 4f n -electrons of lanthanides in oxides by their spectral parameters have much in common with the M 3d-electrons in oxides of the 3d-transition metals. According to these data, the Ln 4f shell of lanthanides is rather outer and can participate in the formation of molecular orbitals in compounds. The XPS data at least do not contradict the theoretical suggestion about the significant participation of the Ln 4f-electrons in formation of the molecular orbitals in the studied materials. The spectra in the Ln 5p-O 2s binding energy region of the studied lanthanide oxides were found to exhibit the complicated structure instead of separated peaks due to the electrons of the Ln 5p 3/2,5/2 and O 2s atomic shells. Taking into account the energy differences between the inner (Ln 3d) and outer (Ln 5p) electronic shells for some metallic lanthanides and their oxides, the Ln 5p atomic shells were shown to participate in the formation of the inner valence molecular orbitals (IVMO). That agrees qualitatively with the calculation results

An XPS study of bromine in methanol etching and hydrogen peroxide passivation treatments for cadmium zinc telluride radiation detectors

International Nuclear Information System (INIS)

Babar, S.; Sellin, P.J.; Watts, J.F.; Baker, M.A.

2013-01-01

Highlights: ► CdZnTe single crystal etched in bromine-in-methanol and passivated in H 2 O 2 . ► XPS depth used to accurately determine enriched Te layer and TeO 2 thickness. ► For 0.2 and 2.0 (v/v) % bromine-in-methanol treatments, enriched Te layer thickness determined to be 1.3 and 1.8 nm, respectively. ► After passivation in 30 wt.% H 2 O 2 , the oxide thickness varies between 1.0 and 1.25 nm depending on the calculation method. - Abstract: The performance of single crystal CdZnTe radiation detectors is dependent on both the bulk and the surface properties of the material. After single crystal fabrication and mechanical polishing, modification of the surface to remove damage and reduce the surface leakage current is generally achieved through chemical etching followed by a passivation treatment. In this work, CdZnTe single crystals have been chemically etched using a bromine in methanol (BM) treatment. The BM concentrations employed were 0.2 and 2.0 (v/v) % and exposure times varied between 5 and 120 s. Angle resolved XPS and sputter depth profiling has been employed to characterize the surfaces for the different exposure conditions. A Te rich surface layer was formed for all exposures and the layer thickness was found to be independent of exposure time. The enriched Te layer thickness was accurately determined by calibrating the sputter rate against a CdTe layer of known thickness. For BM concentrations of 0.2 (v/v) % and 2 (v/v) %, the Te layer thickness was determined to be 1.3 ± 0.2 and 1.8 ± 0.2 nm, respectively. The BM etched surfaces have subsequently been passivated in a 30 wt.% H 2 O 2 solution employing exposure time of 15 s. The oxide layer thickness has been calculated using two standard XPS methodologies, based on the Beer–Lambert expression. The TeO 2 thickness calculated from ARXPS data are slightly higher than the thickness obtained by the simplified Beer–Lambert expression. For BM exposures of 30–120 s followed by a passivation

Core-level XPS studies of Ce and La intermetallic compounds and their implications for the 4f levels of Ce compounds

International Nuclear Information System (INIS)

Freiburg, C.; Fuggle, J.C.; Hillebrecht, F.U.; Zolnierek, Z.; Laesser, R.

1983-01-01

The 3d core hole X-ray photoelectron spectra (XPS) of approximately 30 intermetallic compounds of La and Ce are reported. Transitions to final states with approximately f 0 , f 1 and f 2 character are observed in some Ce compounds (f 0 and f 1 for La compounds). The results are discussed in terms of the current ideas of the influence of f-counts and f-levels hybridization on core level lineshapes. We cannot find an explanatoin of the observed spectra consisted with the ''promotial model'' where the 4f-count varies and 4f electron was thought to be entirely promoted to the Ce 5d6s valence bands in some compounds. There may be some small charge transfer from the f level, however. In conjunction with ideas on screening processes in XPS the observed lineshapes suggest coupling of the 4f electrons to other states is strongest in those compounds previously thought to have f 0 character. This coupling increases despite a large increase in the Ce-Ce distance when Ce is diluted with Ni or Pd. Thus it cannot be due to direct f-f interaction and must be attributed to coupling with the other valence electrons; possibly those centred on the partner sites. (orig./EZ) [de

Synthesis, structural, X-ray photoelectron spectroscopy (XPS) studies and IR induced anisotropy of Tl{sub 4}HgI{sub 6} single crystals

Energy Technology Data Exchange (ETDEWEB)

Parasyuk, O.V. [Department of Inorganic and Physical Chemistry, Lesya Ukrainka Eastern European National University, Voli Ave. 13, Lutsk, 43025 (Ukraine); Khyzhun, O.Y. [Frantsevych Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, 3 Krzhyzhanivsky St., 03142, Kyiv (Ukraine); Piasecki, M. [Institute of Physics, J. Dlugosz University Częstochowa, Armii Krajowej 13/15, Częstochowa (Poland); Kityk, I.V., E-mail: iwank74@gmail.com [Electrical Engineering Department, Czestochowa University Technology, Armii Krajowej 17, PL-42-217, Czestochowa (Poland); Lakshminarayana, G. [Wireless and Photonic Networks Research Centre, Faculty of Engineering, Universiti Putra Malaysia, 43400, Serdang, Selangor (Malaysia); Luzhnyi, I. [Frantsevych Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, 3 Krzhyzhanivsky St., 03142, Kyiv (Ukraine); Fochuk, P.M. [Yuriy Fed’kovych Chernivtsi National University, 2 Kotziubynskoho Str., 58012, Chernivtsi (Ukraine); Fedorchuk, A.O. [Department of Inorganic and Organic Chemistry, Lviv National University of Veterinary Medicine and Biotechnologies, Pekarska Street 50, 79010, Lviv (Ukraine); Levkovets, S.I.; Yurchenko, O.M.; Piskach, L.V. [Department of Inorganic and Physical Chemistry, Lesya Ukrainka Eastern European National University, Voli Ave. 13, Lutsk, 43025 (Ukraine)

2017-02-01

In the present work, we report on the synthesis and structural properties including X-ray protoelectron spectroscopy (XPS) analysis of Tl{sub 4}HgI{sub 6} crystals that were grown by Bridgman-Stockbarger method up to 80 mm in length and 18 mm in diameter. The existence of the ternary compound Tl{sub 4}HgI{sub 6} that melts incongruently at 641 K was confirmed. Phase equilibria and structural properties for the TlI–HgI{sub 2} system were investigated by differential thermal analysis (DTA) and X-ray diffraction (XRD) methods. X-ray photoelectron spectra were measured for both pristine and Ar{sup +} ion-bombarded Tl{sub 4}HgI{sub 6} single crystal surfaces. The data reveal that the Tl{sub 4}HgI{sub 6} single crystal is sensitive with respect to Ar{sup +} ion-bombardment as 3.0 keV Ar{sup +} irradiation over 5 min at an ion current density 14 μA/cm{sup 2} induces changes to the elemental stoichiometry of the Tl{sub 4}HgI{sub 6} surface, leading to a decrease of the mercury content in the topmost surface layers. X-ray photoelectron spectroscopy (XPS) measurements indicate very low hygroscopic nature of the Tl{sub 4}HgI{sub 6} single crystal surface. The IR coherent bicolor laser treatment at wavelengths 10.6/5.3 μm has shown an occurrence of anisotropy at wavelengths 1540 nm of Er:glass laser. This may open the applications of Tl{sub 4}HgI{sub 6} as a material for IR laser triggering. - Highlights: • Phase diagram of the HgI{sub 2}–TlI system was built. • Tl{sub 4}HgI{sub 6} single crystals were grown by Bridgman Stockbarger method. • XRD, XPS analysis was done. • Ir induced anisotropy was established. • The compounds may be proposed as Ir laser operated polarizers.

Encefalopatía por priones

Directory of Open Access Journals (Sweden)

Carlos Colegial

1999-01-01

Full Text Available Las encefalopatías espongiformes por priones son enfermedades neurodegenerativas que pueden ser esporádicas o transmisibles, ya sea por mecanismos infecciosos o hereditarios. Su investigación ha planteado enormes retos y en el recorrido histórico en busca de su causa dos médicos han recibido el premio Nobel de Medicina: Carleton Gajdusek, por sus trabajos en Nueva Guinea donde describió la transmisión infecciosa por ritos canibalísticos, que llevó a estudios de transmisión experimental en chimpancés y a su teoría de los "virus lentos" (por el largo período de incubación de la enfermedad.

Characterization of uranium bioaccumulation on a fungal isolate Geotrichum sp. dwc-1 as investigated by FTIR, TEM and XPS

International Nuclear Information System (INIS)

Changsong Zhao; Congcong Ding; Jiali Liao; Jijun Yang; Yuanyou Yang; Jun Tang; Ning Liu; Qun Sun

2016-01-01

In this paper, TEM-EDX, FTIR, XPS, PIXE, and EPBS were employed to identify the uranium biosorption behavior and the potential mechanism on cells of Geotrichum sp. dwc-1, isolated from soils. These results displayed that the biosorption behavior was greatly dependent on pH and uranium was absorbed by bounding to amino, phosphate as well as carboxyl functional groups. Uranium biosorption behavior on Geotrichum sp. dwc-1 involves bioaccumulation, electrostatic interaction and ion exchange process. This work throws further light on potential fungal roles these mechanisms for elemental recovery and bioremediation. (author)

Fatores associados à procura de serviços de saúde entre escolares brasileiros: uma análise da Pesquisa Nacional de Saúde do Escolar (PeNSE), 2012

OpenAIRE

Oliveira, Max Moura de; Andrade, Silvânia Suely Caribé de Araújo; Campos, Maryane Oliveira; Malta, Deborah Carvalho

2015-01-01

Os objetivos foram descrever a procura por serviços/profissionais de saúde por escolares brasileiros e identificar fatores associados. Foram analisados dados da Pesquisa Nacional de Saúde do Escolar 2012; estimadas as prevalências e seus respectivos intervalos de 95% de confiança (IC95%) do uso de serviços de saúde entre os escolares. Foi feita regressão logística ajustada por idade. Metade dos estudantes buscaram serviços de saúde; a procura foi maior no sexo feminino; os fatores associados ...

XPS analysis of PE and EVA samples irradiated at different γ-doses

Science.gov (United States)

Dorey, Samuel; Gaston, Fanny; Marque, Sylvain R. A.; Bortolotti, Benjamin; Dupuy, Nathalie

2018-01-01

The principal plastic materials used for the fluid contact and storage in the biopharmaceutical industry are mainly made up of semi-crystalline polymers, polyolefins, PVC, Siloxane and PET. The polyethylene (PE) and the polypropylene (PP) are often used as fluid contact in multi-layer materials like films. As one sterilisation way of single-use plastic devices used in medical and pharmaceutical fields can take place via γ-irradiation, the effect of sterilization on plastics must be investigated. The irradiation process leads to the production of radicals, which can generate changes in the polymer structure and on the polymer surface. It is well known that the presence of oxygen with free radicals precede the generation of peroxide species so called ROS (reactive oxygen species) which are highly reactive. The purpose of this work is to investigate the γ-rays impact on the surface of PE (polyethylene) and EVA (polyethylene vinyl alcohol) based films when ionized at different doses. X-ray Photoelectron Spectroscopy (XPS) was applied to determine the surface compositions of the polymers to highlight the different chemical moieties generated during the γ-irradiation process and to monitor the potential presence of the ROS.

X ray photoelectron spectroscopy (XPS) analysis of Photosensitive ZrO2 array

Science.gov (United States)

Li, Y.; Zhao, G.; Zhu, R.; Kou, Z.

2018-03-01

Based on organic zirconium source as the starting material, by adding chemical modifiers which are made up with photosensitive ZrO2 sol. A uniformed ZrO2 array dot was fabricated with a mean diameter of around 800 nm. By using UV-vis spectra and X-ray photoelectron spectroscopy analysis method, studies the photosensitive ZrO2 gel film of photochemical reaction process and the photosensitive mechanism, to determine the zirconium atom centered chelate structure, reaction formed by metal chelate Zr atom for the center, and to establish the molecular model of the chelate. And studied the ultraviolet light in the process of the variation of the XPS spectra, Zr3d5/2 to 184.9 eV corresponding to the binding energy of the as the combination of state peak gradually reduce; By combining with the status of Zr-O peak gradually increase; The strength of the peak is gradually decline. This suggests that in the process of ultraviolet light photo chemical reaction happened. This study is of great significance to the micro fabrication of ZrO2 array not only to the memory devices but also to the optical devices.

Casipoemas por Navidad : (1969-2010)

OpenAIRE

Sena Medina, Guillermo

2011-01-01

PRESENTACIÓN AL AIRE DE LA POESÍA RELIGIOSA Y NAVIDEÑA DE GUILLERMO SENA MEDINA Constituye un gran honor hacer la presentación de Guillermo Sena Medina por un doble motivo; por la larga y sincera amistad que nos une desde hace muchos años al socaire de nuestra común afición por la Historia, como cronistas oficiales de nuestros municipios; y, sobre todo y particularmente, por su rica y profunda personalidad como hombre de letras, nacida de su aún más rica y profunda personalidad humana. A...

Similaridade genética entre clones de seringueira (Hevea brasiliensis, por meio de marcadores RAPD Genetic similarity among rubber tree (Hevea brasiliensis clones using RAPD markers

Directory of Open Access Journals (Sweden)

Karine Cristina Bicalho

2008-10-01

Full Text Available A seringueira [Hevea brasiliensis (Willd. ex. Adr. de Juss Muell.-Arg.] é uma espécie nativa da região amazônica e compreende a maior fonte produtora de borracha natural do mundo. Na busca de condições mais favoráveis ao cultivo, além da busca pela auto-suficiência na produção de borracha natural, o cultivo da seringueira migrou para outras regiões do país. Objetivou-se, com o presente trabalho, estimar a similaridade genética de genótipos de seringueira, provenientes de regiões distintas do país, Lavras-MG (UFLA e Campinas-SP (IAC, por meio de marcadores moleculares RAPD. A análise foi efetuada em 41 indivíduos, representados por 17 genótipos diferentes, com base em 19 primers, que geraram 121 fragmentos polimórficos. Os dados foram analisados utilizando o software NTSYS-pc - 2.1, por meio do coeficiente de Dice e pelo método das médias (UPGMA. A similaridade genética entre o material analisado variou de 0,56 a 1,00. Na análise do dendrograma, foram observados 18 grupos. Os clones (RRIM600, GT1, PB235, PL PIM e FX2261, utilizados em diferentes repetições, foram idênticos, quando comparados entre si, entretanto o mesmo não foi observado para os clones identificados como RRIM 701. Os resultados obtidos sugerem que o material avaliado na UFLA é o mesmo implantado no IAC, exceto o RRIM 701, mostrando uma ampla variabilidade genética, disponível para estudos e propagação da cultura.The rubber tree [Hevea brasiliensis (Willd. ex. Adr. de Juss Muell.-Arg.] is a native species from Amazon region, and represents the biggest source of natural rubber in the world.. However, the rubber tree culture has had an expansion to other brazilian regions, in search of more favorable conditions for its cultivation and self-sufficiency in natural rubber. The aim of this work was to estimate genetic similarity among rubber tree clones, from different Brazilian regions, Lavras (UFLA and Campinas (IAC, by using RAPD molecular markers

XPS study of influence of exposure to air on thermal stability and kinetics of hydrogen decomposition of MgH{sub 2} films obtained by direct hydrogenation from gaseous phase of metallic Mg

Energy Technology Data Exchange (ETDEWEB)

Dobrovolsky, V.D., E-mail: dobersh@ipms.kiev.ua; Khyzhun, O.Y.; Sinelnichenko, A.K.; Ershova, O.G.; Solonin, Y.M.

2017-02-15

Highlights: • Air influence on thermal stability of MgH{sub 2} have been studied by XPS. • XPS spectra of MgH{sub 2} films obtained at different hydrogen pressures have been studied. • Changes in the chemical state of MgH{sub 2} films depending on time of exposure to air are analyzed. • Correlation exists between chemical surface condition of MgH{sub 2} films and their thermal stableness. • Process of hydrogen desorption from MgH{sub 2} films is studied using TDS for model samples. - Abstract: Mechanism of influence of exposure to air on thermal stability of MgH{sub 2} obtained by direct hydrogenation from the gas phase, the nature of the hydride sensitivity to the negative impact of air and the role of its surface chemical state have not been studied enough. The present article presents data of X-ray photoelectron spectroscopy (XPS) measurements of the Mg 2s, O 1s, C 1s core-level spectra of surface of hydride MgH{sub 2} films derived by gas phase hydrogenation of model samples of metallic Mg, and the evolution of changes in the chemical state of the surface of the hydride films depending on the time of exposure to air and formation conditions (hydrogen pressure and hydrogenation regime). Based on results of XPS, X-ray diffraction (XRD), and thermodesorption spectroscopy (TDS), the existence of a relationship (correlation) between chemical surface condition of hydride MgH{sub 2} films obtained at different hydrogen pressures (3.0 MPa and 11.5 MPa) and their thermal stableness and temperature of the beginning of hydride decomposition has been established.

XPS and XANES studies of biomimetic composites based on B-type nano-hydroxyapatite

Science.gov (United States)

Goloshchapov, D. L.; Gushchin, M. S.; Kashkarov, V. M.; Seredin, P. V.; Ippolitov, Y. A.; Khmelevsky, N. O.; Aksenenko, A. Yu.

2018-06-01

The paper presents an investigation of the local atomic structure of nanocrystalline carbonate-substituted hydroxyapatite (CHAP) contained in biomimetic composites - analogues of intact human tooth tissues. Using the XPS technique, the presence of impurity Mg and F atoms and structurally bound carbon in CHAP, at the concentrations typical of apatite enamel and dentine was determined. The XANES method was used to study the changes occurring in P L2,3 spectra of biocomposites with CHAP, depending on the percentage of the amino acid matrix. The appearance of maxima in the spectra of XANES P L2,3 near 135.7 eV for the samples with the composition of amino acid complex/hydroxyapatite - 5/95, 25/75 and the splitting of a broad peak of 146.9 eV in the spectrum of a biocomposite with a composition of 40/60 indicates at the interaction of molecular complex of amino acids with atomic environment of phosphorus. This fact can be used in the fundamental medicine for synthesizing of new biomaterials in dentistry.

RBS and XPS analyses of the composite calcium phosphate coatings for biomedical applications

International Nuclear Information System (INIS)

Ide-Ektessabi, Ari; Yamaguchi, Tetsuro; Tanaka, Yoshikazu

2005-01-01

The calcium phosphate coatings on metallic implants are widely used for biomedical applications. The calcium phosphate coatings require mechanical strength, strong adhesion to the metallic implants, chemical stability and low dissolution into the human body fluid for stable functioning in the corrosive environment of the human body. In this study, a novel approach for improving the calcium phosphate coatings is utilized by adding trace metallic element into the coatings. We focused on teeth enamel, which is the hardest calcium phosphate tissue in the human body. Zn concentration increases exponentially from the interior to the surface of the enamel. As the Zn concentration increases, so the local hardness increases. Our previous studies suggest that Zn has influence on the hardness and other properties of enamel, calcium phosphate tissue. Calcium phosphate coatings doped with Zn was fabricated and characterized. The atomic composition and chemical state were investigated by using Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectrometer (XPS), respectively. Scratch test was also carried out for measuring the adhesion of the coatings

Vacancy ordered γ-Fe{sub 2}O{sub 3} nanoparticles functionalized with nanohydroxyapatite: XRD, FTIR, TEM, XPS and Mössbauer studies

Energy Technology Data Exchange (ETDEWEB)

Ramos Guivar, Juan A., E-mail: juan.ramos5@unmsm.edu.pe [Faculty of Physical Sciences, National University of San Marcos, P. O. Box 14- 0149, Lima 14 (Peru); Sanches, Edgar A., E-mail: sanches.ufam@gmail.com [Federal University of Amazonas, Department of Physics, Manaus/AM (Brazil); Bruns, Florian, E-mail: f.bruns@tu-braunschweig.de [Institut für Physik der Kondensierten Materie, Technische Universität Braunschweig, 38110 Braunschweig (Germany); Sadrollahi, Elaheh, E-mail: elahe.sadrollahi@gmail.com [Institut für Physik der Kondensierten Materie, Technische Universität Braunschweig, 38110 Braunschweig (Germany); Morales, M.A., E-mail: marco.moralestorres@gmail.com [Department of Theoretical and Experimental Physics, UFRN, Natal, RN 59078- 970 (Brazil); López, Elvis O., E-mail: lopmezel@gmail.com [Brazilian Center for Research in Physics (CBPF), Rio de Janeiro, RJ 22290-180 (Brazil); Litterst, F. Jochen, E-mail: litterst@cbpf.br [Institut für Physik der Kondensierten Materie, Technische Universität Braunschweig, 38110 Braunschweig (Germany); Brazilian Center for Research in Physics (CBPF), Rio de Janeiro, RJ 22290-180 (Brazil)

2016-12-15

Graphical abstract: Possible bonding configuration in the γ-Fe{sub 2}O{sub 3} nanoparticles functionalized with nanoHAp. - Highlights: • Coprecipitation in alkaline medium for the synthesis of vacancy ordered γ-Fe{sub 2}O{sub 3}@HAp nanocomposite. • Samples were characterized by XRD, FTIR, XPS, TEM, VSM and Mössbauer spectroscopy. • The functionalization is explained with the binding of two oxygens of chemisorbed H{sub 2}O molecules at the common interface of HAp/C{sub 6}H{sub 8}O{sub 7}/γ-Fe{sub 2}O{sub 3}. - Abstract: Vacancy ordered maghemite (γ-Fe{sub 2}O{sub 3}) nanoparticles functionalized with nanohydroxyapatite (HAp – Ca{sub 10}(PO{sub 4}) {sub 6}(OH){sub 2}) have been successfully synthesized using an inexpensive co-precipitation chemical route. Evidence for the presence of vacancy order in maghemite was shown by the superstructure lines observed in X-ray diffraction. The adsorption of carboxyl groups of citric acid (C{sub 6}H{sub 8}O{sub 7}) onto γ-Fe{sub 2}O{sub 3} nanoparticles was investigated by FTIR, XPS and Mössbauer spectroscopy. From XPS surface analysis, two binding energies related to oxygen were attributed to bindings between C{sub 6}H{sub 8}O{sub 7}/γ- Fe{sub 2}O{sub 3} and C{sub 6}H{sub 8}O{sub 7}/HAp from an interfacial reaction promoted by strongly adsorbed H{sub 2}O molecules at the surface of these nanomaterials. Le Bail refinement of the XRD patterns showed the formation of well-crystallized pure tetragonal maghemite before and after functionalization with nanoHAp. The temperature dependence of hyperfine parameters of pure and functionalized γ-Fe{sub 2}O{sub 3} nanoparticles was investigated via Mössbauer spectroscopy. TEM revealed the formation of quasi-spherical γ- Fe{sub 2}O{sub 3} nanoparticles with an average diameter of ca. 12 nm and 16 nm before and after functionalization with nanoHAp in agreement with Le Bail refinement. Magnetometry measurements showed a saturation magnetization of 12 emu/g and a blocking

Metodología de Gestión por Competencias Asumiendo la Norma Cubana sobre Gestión de Capital HumanoMetodologia de Gestão por Competências Assumindo a Norma Cubana sobre Gestão de Capital HumanoMethodology of Competences Management Assuming the Cuban Norm about Management of Human Capital

Directory of Open Access Journals (Sweden)

SANTOS, Armando Ramón Cuesta

2011-09-01

Full Text Available RESUMOO presente estudo se consiste em uma pesquisa realizada em oito empresas cubanas que seguiam o enfoque de competências na gestão estratégica de recursos humanos segundo a norma cubana NC:3000-3002:2007 sobre gestão do capital humano visando um desempenho de maior produtividade. O objetivo do estudo é apresentar um modelo de gestão de desempenho por competências com base nas normas citas e nos casos analisados. Para o desenvolvimento do modelo procurou-se relacionar o desempenho individual por competências com o desempenho organizacional. Como resultado pode-se apresentar um modelo de gestão de desempenho por competências dos diversos níveis organizacionais com base nas Normas Cubanas mencionadas.ABSTRACTAn applied research conducted in eight Cuban companies which follow the approach of skills in strategic management of human resources according to the standard Cuban CN: 3000-3002:2007 on human capital management, seeking a superior performance to higher productivity. It sought to manage the connection of individual work with the responsibilities for the strategic organizational performance. As a result we have obtained a metodology to manage the various skill levels expressed in this companies, which acceptance of the competence concept in the position is fundamental in the NC mentioned. Presenting this methodology for performance management competence is the mais purpose of this article.RESUMENUna investigación aplicada realizada en ocho empresas cubanas que estaban siguiendo el enfoque de competencias en gestión estratégica de recursos humanos, asumiendo la norma cubana NC: 3000-3002: 2007 sobre gestión de capital humano, en aras de un desempeño superior o de mayor productividad, buscó gestionar el vínculo del desempeño individual por competencias con el desempeño organizacional o estratégico. Como resultado se obtuvo una metodología de gestión de los distintos niveles de competencias que se expresan en esas

O LUGAR DE OCUPAÇÃO DO SUJEITO EM PEÇAS PUBLICITÁRIAS

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Maria Ieda Almeida Muniz

2011-03-01

Full Text Available Partindo dos conceitos de enunciação postulados por Benveniste (1989, Ducrot (1987, 2002 e Guimarães (1989; 1995; 1996 e 2002, associados aos estudos de Dias (2002, entre outros; procuramos evidenciar os lugares de ocupação do sujeito e recortamos um exemplário de ocorrências extraídas de anúncios publicitários veiculados em fontes diversas. Por meio dos dados analisados, verificamos o caráter multifacetado que a língua pode apresentar, não fazendo sentido porfiar por uma formulação exata, estrita e restritiva de uma só possibilidade de análise, o que não caracteriza a abordagem como falha, ou imprecisa. Nessa direção, concluímos que o estudo da linguagem, do ponto de vista de uma sintaxe de bases enunciativas, contempla o uso relativo a tempo, espaço e sujeito da enunciação e a consideração de que enunciar é um ato singular de utilização da língua e como tal deve ser analisado.

XPS and XAES measurements on trapped rare gases in transition metals

International Nuclear Information System (INIS)

Baba, Y.; Yamamoto, H.; Sasaki, T.A.

1992-01-01

Electronic structures of rare gases implanted in various transition metals have been investigated by means of an X-ray photoelectron spectroscopy (XPS) and X-ray-induced Auger electron spectroscopy (XAES). The Auger-parameter method is applied to the evaluation of electronic relaxation energy of rare gas atoms due to the surrounding metal potential. The extra-atomic relaxation energy of four kinds of rare gases (Ne, Ar, Kr, Xe) in the same metal matrix (Ti) increases with the atomic mass of the rare gases. On the other hand, the extra-atomic relaxation energy of the same rare gas (Xe) in different metal matrices ranges from 3.0 eV (in Mo). These values increase with the number of d-electrons in the metals. This tendency and the absolute values of the relaxation energies are in good agreement with those calculated for 3d transition metals referenced to their gas-phase values. Based on these results, it is concluded that the energetically implanted rare gases are trapped at the substitution site in the metal lattice as an isolated atom, and the trapped atoms feel the surrounding metal potential. It is also made clear that the potential affecting the implanted atom is d-like, and the relaxation energy of the implanted rare gas during the photoemission process is almost equal to those of the metal itself. (orig.)

Incorporation of low energy activated nitrogen onto HOPG surface: Chemical states and thermal stability studies by in-situ XPS and Raman spectroscopy

Science.gov (United States)

Chandran, Maneesh; Shasha, Michal; Michaelson, Shaul; Hoffman, Alon

2016-09-01

In this paper we report the chemical states analysis of activated nitrogen incorporated highly oriented pyrolytic graphite (HOPG) surface under well-controlled conditions. Nitrogen incorporation is carried out by two different processes: an indirect RF nitrogen plasma and low energy (1 keV) N2+ implantation. Bonding configuration, concentration and thermal stability of the incorporated nitrogen species by aforesaid processes are systematically compared by in-situ X-ray photoelectron spectroscopy (XPS). Relatively large concentration of nitrogen is incorporated onto RF nitride HOPG surface (16.2 at.%), compared to N2+ implanted HOPG surface (7.7 at.%). The evolution of N 1s components (N1, N2, N3) with annealing temperature is comprehensively discussed, which indicates that the formation and reorganization of local chemical bonding states are determined by the process of nitridation and not by the prior chemical conditioning (i.e., amorphization or hydrogenation) of the HOPG surface. A combined XPS and Raman spectroscopy studies revealed that N2+ implantation process resulted in a high level of defects to the HOPG surface, which cannot be annealed-out by heat treatment up to 1000 °C. On the other hand, the RF nitrogen plasma process did not produce a high level of surface defects, while incorporating nearly the same amount of stable nitrogen species.

Microstructural study by XPS and GISAXS of surface layers formed via phase separation and percolation in polystyren/tetrabutyl titanate/alumina composite films

International Nuclear Information System (INIS)

Zeng Yanwei; Tian Changan; Liu Junliang

2006-01-01

The XPS and GISAXS have been employed as useful tools to probe the chemical compositional and microstructural evolutions in the surface layers formed via phase separation and percolation in polystyren/Ti(OBut) 4 /alumina composite thick films. The surface enrichment of Ti species due to the migration of Ti(OBut) 4 molecules in the films was found to show an incubation period of ∼15 h while the samples were treated at 100 deg. C before a remarkable progress can be identified. According to the XPS and GISAXS data, Key mechanism to govern this surface process is phenomenologically considered to be the specific phase separation behavior in Ti(OBut) 4 /PS blend and the subsequent percolating process. The extended thermal treatment was found to make the surface layer microstructure evolve from local phase separation featured with an increasing population of individual microbeads of Ti(OBut) 4 (∼1.5 nm in radius) to the formation of large size clusters of microbeads due to their interconnections, accompanied by the growth of every microbead itself to ∼10 nm on the average, which provokes and then enhances the surface enrichment of Ti(OBut) 4 since these clusters act as a fast diffusion network due to percolation effect

Interaction of cysteine and copper ions on the surface of iron: EIS, polarization and XPS study

International Nuclear Information System (INIS)

El-Deab, Mohamed S.

2011-01-01

Highlights: → The current study demonstrates a comprehensive study for Cysteine + Cu(II) ions as an efficient inhibitor as demonstrated by EIS, XPS and potentiodynamic polarization measurements, in addition to traditional weight loss measurements. → The novelty of the current work originates from the combined use of an eco-friendly compound (i.e., cysteine) with a minute amount of copper ions (in the micro molar range) as a corrosion inhibitor for low carbon steel in acidic medium. To this end, cysteine shows only moderate inhibition ca. 60% for iron which jumps up to more than 95% in the presence of micro molar range of Cu(II) ions. → Cysteine-Cu(II) blends are found superior to benzotriazole (BTAH)-Cu(II) blends in terms of their long-term stability in addition to the avoidance of the use of the well-reported highly toxic BTAH. - Abstract: This study addresses the enhancing effect of copper ions on the inhibition efficiency (IE) of cysteine (an eco-friendly compound) against the corrosion of iron in 0.5 M sulphuric acid. Electrochemical impedance spectroscopy (EIS) data revealed a significant increase in the polarization resistance (R p ) of the iron/solution interface in the presence of cysteine and Cu(II) ions instead of cysteine alone. That is, IE of 95% is obtained in the presence of 5 mM cysteine and 25 μM Cu(II) ions, compared to 66% in absence of Cu(II) ions. Moreover, electrochemical polarization measurements indicate that cysteine and Cu(II) ions blends act as mixed-type inhibitors for the corrosion of iron. The formation of Cu(I)-cysteinate complex and/or cysteine SAM at Cu atop the iron surface (as evident from X-ray photoelectron spectroscopy (XPS)) blocks the underlying iron surface and imparts a pronounced protection against its corrosion. IE of cysteine-Cu(II) blend remains effectively unchanged with immersion time indicating its high stability in the used acidic medium.

Evolution of NADPH-cytochrome P450 oxidoreductases (POR) in Apiales - POR 1 is missing

DEFF Research Database (Denmark)

Andersen, Trine Bundgaard; Hansen, Niels Bjørn; Laursen, Tomas

2016-01-01

The NADPH-dependent cytochrome P450 oxidoreductase (POR) is the obligate electron donor to eukaryotic microsomal cytochromes P450 enzymes. The number of PORs within plant species is limited to one to four isoforms, with the most common being two PORs per plant. These enzymes provide electrons to ...... (available from the SRA at NCBI). All three genes were shown to be functional upon reconstitution into nanodiscs, confirming that none of the isoforms are pseudogenes....

Sinalizando com os Terena: um estudo do uso da LIBRAS e de sinais nativos por indígenas surdos

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Priscilla Alyne Sumaio

2016-04-01

Full Text Available O povo terena habita os estados de Mato-Grosso do Sul e São Paulo. Essa etnia conta com 28.845 pessoas (dados do IBGE, 2010, que estão divididas em 17 terras. Constataram-se terena surdos primeiramente na Comunidade Indígena de Cachoeirinha, de 9.507 habitantes e, em segunda viagem a campo, também em aldeias vizinhas, próximas ao município de Miranda-MS. A língua oral terena é amplamente falada, e também foi observado o uso de sinais pelos surdos terena, o que deu origem a esta pesquisa. O projeto envolveu o estudo da(s língua(s utilizadas por surdos terena de diferentes faixas etárias, sendo a maioria jovens. É notável que parte dessas pessoas não conheça a língua brasileira de sinais (LIBRAS. Alguns nunca frequentaram a escola ou tiveram contato com surdos usuários de LIBRAS. De maneira geral, os familiares dos surdos são ouvintes e falantes de português e terena, e os mais próximos conhecem os sinais terena. Alguns jovens estudam na cidade e estão avançando no uso e conhecimento da LIBRAS, porém estes mesmos jovens utilizam outros sinais na aldeia, com seus familiares ouvintes, amigos e outros surdos, que não sabem LIBRAS. Em última viagem a campo, em 2012, foram coletados sinais terena por meio de fotografia e vídeo, que foram analisados. Avaliou-se então a estrutura, a morfologia no uso desses sinais, e se chegam realmente a constituir uma língua. Entretanto, nesse momento, os aspectos linguísticos não puderam ser mais aprofundados, pois ainda está coletada uma quantidade reduzida de dados, que deverá ser aumentada para a pesquisa do doutorado. Observei também a cultura, educação, cosmovisão terena e surda, as relações dos surdos com seus familiares, professores, intérpretes, amigos e sociedade ouvinte. 

XPS studies of SiO/sub 2/ surface layers formed by oxygen ion implantation into silicon

Energy Technology Data Exchange (ETDEWEB)

Schulze, D.; Finster, J. (Karl-Marx-Universitaet, Leipzig (German Democratic Republic). Sektion Chemie); Hensel, E.; Skorupa, W.; Kreissig, U. (Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic))

1983-03-16

SiO/sub 2/ surface layers of 160 nm thickness formed by /sup 16/O/sup +/ ion implantation into silicon are examined by X-ray photoelectron spectroscopy measurements into the depth after a step-by-step chemical etching. The chemical nature and the thickness of the transition layer were determined. The results of the XPS measurements show that the outer surface and the bulk of the layers formed by oxygen implantation and subsequent high temperature annealing consist of SiO/sub 2/. There is no evidence for Si or SiO/sub x/ (0

Análise da positividade da esquistossomose mansoni em Regionais de Saúde endêmicas em Pernambuco, 2005 a 2010

OpenAIRE

Barreto, Ana Virgínia Matos Sá; Melo, Nobélia Duarte; Ventura, Jéssica Valença Torres; Santiago, Rosimery Tavares; Silva, Maria Beatriz Araújo

2015-01-01

OBJETIVO: analisar a tendência da positividade da esquistossomose em exames coproscópicos na população de área endêmica do estado de Pernambuco, Brasil, de 2005 a 2010. MÉTODOS: estudo ecológico de serie temporal, com dados secundários do Sistema de Informação do Programa de Controle da Esquistossomose, analisados por Regional de Saúde; foram avaliadas as tendências por regressão linear, considerando-se p

Diabetes gestacional na perspectiva de mulheres grávidas hospitalizadas

OpenAIRE

Araújo, Márcio Flávio Moura; Pessoa, Sarah Maria Fraxe; Damasceno, Marta Maria Coelho; Zanetti, Maria Lúcia

2013-01-01

Estudo qualitativo fenomenológico, que teve como objetivo compreender o significado das experiências vivenciadas por mulheres com diabetes mellitus gestacional. Participaram 12 pacientes internadas em uma maternidade de Fortaleza-CE, Brasil, que manifestaram seus sentimentos e percepções por meio de entrevista aberta e desenhos. O material empírico foi transcrito na íntegra e, posteriormente, organizado e analisado pelo método fenomenológico. Os resultados evidenciaram dois temas: (1) Vivenci...

Diabetes gestacional na perspectiva de mulheres grávidas hospitalizadas Diabetes gestacional desde la perspectiva de mujeres embarazadas hospitalizadas Gestational diabetes from the perspective of hospitalized pregnant women

OpenAIRE

Márcio Flávio Moura Araújo; Sarah Maria Fraxe Pessoa; Marta Maria Coelho Damasceno; Maria Lúcia Zanetti

2013-01-01

Estudo qualitativo fenomenológico, que teve como objetivo compreender o significado das experiências vivenciadas por mulheres com diabetes mellitus gestacional. Participaram 12 pacientes internadas em uma maternidade de Fortaleza-CE, Brasil, que manifestaram seus sentimentos e percepções por meio de entrevista aberta e desenhos. O material empírico foi transcrito na íntegra e, posteriormente, organizado e analisado pelo método fenomenológico. Os resultados evidenciaram dois temas: (1) Vivenci...

Análise do gene PTEN por hibridização in situ fluorescente no carcinoma de células renais

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Eurico Cleto Ribeiro de Campos

Full Text Available OBJETIVO: avaliar a frequência de deleção do gene PTEN no carcinoma de células renais e o impacto da deleção nas taxas de sobrevida global e livre de doença. MÉTODOS: foram analisados 110 pacientes portadores de carcinoma de células renais submetidos à nefrectomia radical ou parcial entre os anos de 1980 e 2007. Em 53 casos foi possível a análise do gene PTEN pelo método de hibridização in situ fluorescente através da técnica de "tissue microarray". Para a análise estatística, os pacientes foram classificados em dois grupos, de acordo com a presença ou ausência de deleção. RESULTADOS: o tempo médio de seguimento foi de 41,9 meses. Deleção hemizigótica foi identificada em 18 pacientes (33,9%, ao passo que deleção homozigótica esteve presente em três (5,6%. Em aproximadamente 40% dos casos analisados havia deleção. Monossomia e trissomia foram detectadas, respectivamente, em nove (17% e dois pacientes (3,8%. Em 21 pacientes (39,6%, a análise por hibridização in situ do gene PTEN foi normal. Não houve diferenças estatisticamente significativas nas taxas de sobrevida global (p=0,468 e livre de doença (p=0,344 entre os pacientes portadores ou não de deleção. Foram fatores independentes para a sobrevida global: estádio clínico TNM, sintomatologia ao diagnóstico, alto grau de Fuhrmann performance status (Ecog e recorrência tumoral. A livre de doença foi influenciada unicamente pelo estádio clínico TNM. CONCLUSÃO: deleção do gene PTEN no CCR foi detectada com frequência de aproximadamente 40% e sua presença não foi determinante de menores taxas de sobrevida, permanecendo os fatores prognósticos tradicionais como determinantes da evolução dos pacientes.

Por que ocorre? Como lidar? A percepção de professores de graduação em Administração sobre o assédio moral

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Roberto Brazileiro Paixão

2013-09-01

Full Text Available Tem-se observado em muitas pesquisas que o assédio moral do aluno para com o professor tem sido incrementado com o processo de mercantilização do ensino superior. Tal processo insere-se num cenário de desvalorização da figura do professor e de exaltação da concepção do aluno-cliente. Nesse sentido, abre-se espaço para práticas de assédio moral na relação aluno-professor. O propósito neste artigo é compreender por que acontece o assédio moral no vetor aluno-professor e o que pode ser feito para que esse comportamento seja evitado. Para cumprir o objetivo da investigação, foram coletados e analisados, pelo método do discurso do sujeito coletivo (DSC de caráter qualiquantitativo, os depoimentos provenientes de 51 questionários respondidos por professores universitários. A análise das respostas dos professores universitários às questões de pesquisa oferece uma percepção do por quê da ocorrência do assédio moral aluno-professor na visão dos pesquisados, os quais identificam motivos que vão desde valores sociais não apreendidos até a mercantilização do ensino. A partir das respostas, verificam-se possibilidades de ação que apontam prioritariamente a discussão institucional como meio de suporte à vítima e como alicerce para ações preventivas, dentre outras atitudes individuais que influenciam positivamente esse tipo de assédio, e mesmo a disputa judicial como última instância para a solução do problema.

Novel immobilizations of an adhesion peptide on the TiO2 surface: An XPS investigation

International Nuclear Information System (INIS)

Iucci, G.; Dettin, M.; Battocchio, C.; Gambaretto, R.; Bello, C. Di; Polzonetti, G.

2007-01-01

The covalent attachment of an adhesive peptide, reproducing the 351-359 sequence of human vitronectin, to oxidized titanium surfaces was investigated by XPS spectroscopy. The peptide enhances osteoblast adhesion to titanium, the most used biomaterial for implants and prostheses. Core level spectra of the TiO 2 surface and of the biomimetic surface were investigated. Novel selective covalent immobilization of (351-359) HVP was carried out by treatment of the TiO 2 surface with (3-aminopropyl) triethoxysilane, glutaric anhydride and a side chain protected peptide sequence presenting only a free terminal amino group, followed by side chain deprotection. An alternative strategy for covalent attachment consists in photoactivation of physisorbed (351-359) HVP directly on the TiO 2 surface; samples were incubated with HVP solution and subsequently irradiated with UV light. A comparison with the results previously obtained for non-selective HVP immobilization will be discussed

InP/ZnS nanocrystals: coupling NMR and XPS for fine surface and interface description.

Science.gov (United States)

Virieux, Héloïse; Le Troedec, Marianne; Cros-Gagneux, Arnaud; Ojo, Wilfried-Solo; Delpech, Fabien; Nayral, Céline; Martinez, Hervé; Chaudret, Bruno

2012-12-05

Advanced (1)H, (13)C, and (31)P solution- and solid-state NMR studies combined with XPS were used to probe, at the molecular scale, the composition (of the core, the shell, and the interface) and the surface chemistry of InP/ZnS core/shell quantum dots prepared via a non-coordinating solvent strategy. The interface between the mismatched InP and ZnS phases is composed of an amorphous mixed oxide phase incorporating InPO(x) (with x = 3 and predominantly 4), In(2)O(3), and InO(y)(OH)(3-2y) (y = 0, 1). Thanks to the analysis of the underlying reaction mechanisms, we demonstrate that the oxidation of the upper part of the InP core is the consequence of oxidative conditions brought by decarboxylative coupling reactions (ketonization). These reactions occur during both the core preparation and the coating process, but according to different mechanisms.

Escolha de destino para eventos: uma análise dos atributos considerados na tomada de decisão por organizadores e promotores de eventos

Directory of Open Access Journals (Sweden)

Bruna Dorabiallo Oliveira

2017-06-01

Full Text Available O turismo de eventos provoca grande atratividade econômica para as localidades receptoras, uma vez que os eventos geram fluxo programado de visitantes e o turista tem um gasto médio superior aos demais tipos de turista. Compreender os atributos que a localidade deve apresentar para ser atrativa aos organizadores e promotores de eventos é uma maneira de planejar e desenvolver o turismo em uma região. Com o objetivo de analisar os conjuntos de atributos considerados na escolha de um destino para evento, o presente estudo apresenta uma pesquisa exploratória e através de pesquisa bibliográfica indica os estudos publicados nessa temática na perspectiva dos organizadores e promotores de eventos. Foram analisados 27 artigos que discutem os atributos inerentes à tomada de decisão de destinos para eventos e descritos os 21 diferentes conjuntos de atributos identificados. Verificou-se que se pode categorizar os atributos entre os relacionados ao evento ou ao destino, sendo que estrutura para eventos, hospedagem e custos são predominantes nos estudos, enquanto existem outros atributos são considerados por autores específicos.

Osteomalacia inducida por tumor: hemangiopericitoma rinosinusal

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Enriqueta M. Serafini

2013-02-01

Full Text Available La osteomalacia inducida por tumor es una rara enfermedad del metabolismo óseo caracterizada por el aumento en la excreción de fosfato a nivel renal seguido de hipofosfatemia. Es causada por agentes fosfatúricos producidos por determinados tumores. La resección total del tumor resulta en la completa reversión de las anormalidades bioquímicas, la desaparición de las manifestaciones clínicas y los hallazgos en los estudios por imágenes. Presentamos el caso de un varón de 61 años con cuadro clínico y laboratorio compatibles con osteomalacia oncogénica inducida por tumor mesenquimático de localización rinosinusal. En nuestro caso el diagnóstico histológico correspondió a una neoplasia de tipo vascular: hemangiopericitoma.

Motivações políticas e econômicas da integração energética na América do Sul: o caso de Itaipu * Economic and political motivations for South America energy integration: the case of Itaipu

OpenAIRE

OXILIA, VICTORIO; SAUER, ILDO LUIS; RODRIGUES, LARISSA ARAUJO

2015-01-01

Resumo: O presente artigo analisa o projeto Itaipu Binacional, identificando os grupos de interesse que foram por ele beneficiados. Inicialmente, é apresentado o contexto histórico, político e econômico à época do projeto. Em seguida, são analisados pontos específicos do projeto, como, por exemplo, a evolução dos custos diretos, meios de financiamento e comportamento da dívida, os processos de contratação de empresas para a construção da obra e a provisão de equipamentos. Por fim, é mostrado ...

Comparative analyses between clinical refraction and automatic refraction obtained through a wave front sensor

OpenAIRE

Freitas, Wilson de; Melo Júnior, Luiz Alberto Soares; Schor, Paulo; Campos, Mauro

2007-01-01

OBJETIVO: Avaliar e comparar os resultados obtidos da refração estática clínica com a obtida por sensor de frentes de onda. MÉTODOS: Estudo prospectivo, não seqüencial, de 279 olhos de 147 pacientes. Todos os pacientes foram examinados sob cicloplegia. Primeiro realizamos a refração clínica e a seguir a automatizada por sensor de frentes de onda. Os dados refracionais obtidos foram decompostos para análise vetorial. Foram analisados separadamente os dados de um olho por paciente e dos dois ol...

Ganho de força e função em idosos por treino isométrico com e sem resposta visual

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Mauricio Ferraz de Arruda

2014-07-01

Full Text Available INTRODUÇÃO: A remediação das alterações fisiológicas que sofrem os idosos é um problema com o qual a saúde pública se defronta com frequência. A premência deste trabalho está em minimizar essa remediação e as alterações que ela propicia no âmbito músculo-esquelético, por meio de um trabalho físico condicionante, que busca aumentar a qualidade de vida dessa população. OBJETIVO: Avaliar o efeito do treinamento físico sob duas ópticas de comando terapêutico, com e sem resposta visual por unidade de pressão, bem como seus possíveis benefícios quanto ao ganho de torque muscular, inerente à funcionalidade citada no questionário de qualidade de vida SF-36, avaliando assim a influência do treinamento físico. MÉTODOS: A avaliação foi realizada por meio de um questionário de qualidade de vida SF-36 e do teste de levantar e sentar, além da aferição da força por meio do esfigmomanômetro modificado (EM. O individuo foi submetido a duas sessões semanais de exercícios durante um mês, com o protocolo de treinamento que constou de três séries de 10 repetições na cadeira flexora e extensora para ambos os joelhos de maneira isométrica. Os dados foram estatisticamente analisados pela análise de variância e desvio padrão (p < 0,05 e correlação de Pearson (p < 0,05. RESULTADOS: Notou-se melhora no quadro geral dos idosos, sendo que houve aumento estatisticamente significante no estado geral de saúde, redução da limitação por aspectos físicos, redução da dor e no aumento da capacidade funcional, bem como um incremento da força de flexão e extensão, que teve reflexo positivo no teste funcional. CONCLUSÃO: Houve correlação extremamente válida entre o ganho de força em flexão com o teste de sentar e levantar, com o qual, apesar de ganho menor comparado ao ganho de força em extensão, estabeleceu-se correlação com o ganho funcional, independentemente da resposta visual ao exercício.

Envenenamento por Tityus stigmurus (Scorpiones; Buthidae no Estado da Bahia, Brasil Envenomation by Tityus stigmurus (Scorpiones; Buthidae in Bahia, Brazil

Directory of Open Access Journals (Sweden)

Rejâne Maria Lira-da-Silva

2000-06-01

Full Text Available A presente investigação é um estudo descritivo dos aspectos clínicos dos acidentes causados pelo escorpião Tityus stigmurus no Estado da Bahia, Brasil. Foram analisados 237 casos confirmados, tratados pelo Centro de Informações Antiveneno da Bahia (CIAVE, no período de 1982-1995. O envenenamento por T. stigmurus caracterizou-se por manifestações locais: dor (94,4%, dormência (30%, edema (17,8%, eritema (17,8% e parestesia (15,6% e gerais: cefaléia (14%, vômitos (4,4% e sudorese (3,3%. A maioria dos envenenamentos (94% foi leve e todos evoluíram para cura. A ausência de letalidade, com o restabelecimento dos pacientes, inclusive casos graves, sugere a eficácia do tratamento com o antiveneno específico, apesar do veneno desta espécie não estar presente no pool de produção nacional do soro. Há necessidade de revisão dos critérios regionais nos esquemas atuais de soroterapia. Os dados apontam para a semelhança da gravidade do envenenamento por T. serrulatus, com exceção da ocorrência de óbitos e complicações sistêmicas.The present investigation is a descriptive study regarding the clinical aspects of accidents caused by the scorpion Tityus stigmurus in Bahia, Brazil. We analyzed 237 confirmed cases treated by the Antivenom Information Centre (CIAVE from 1982 to 1995. Envenomation by T. stigmurus was mainly characterized by local symptoms: pain (94.4%, dormancy (30.0%, edema (17.8%, erythema (17.8, paresthesia (15.6% and general manifestations such as headache (4.4%, vomiting (4.4% and sudoresis (3.3%. Most of the envenomation cases were mild (94% and all were successfully cured. Although T. stigmurus venom is not in the pool of anti-venom serum (SAE, the absence of lethality and benign nature of the cases suggest the efficiency of SAE. With the exception of deaths and systemic complications, envenoming gravity was similar to those of Tityus serrulatus.

In Situ Studies of Surface Mobility on Noble Metal Model Catalysts Using STM and XPS at Ambient Pressure

Energy Technology Data Exchange (ETDEWEB)

Butcher, Derek Robert [Univ. of California, Berkeley, CA (United States)

2010-06-01

High Pressure Scanning Tunneling Microscopy (HP-STM) and Ambient Pressure X-ray Photoelectron Spectroscopy were used to study the structural properties and catalytic behavior of noble metal surfaces at high pressure. HP-STM was used to study the structural rearrangement of the top most atomic surface layer of the metal surfaces in response to changes in gas pressure and reactive conditions. AP-XPS was applied to single crystal and nanoparticle systems to monitor changes in the chemical composition of the surface layer in response to changing gas conditions. STM studies on the Pt(100) crystal face showed the lifting of the Pt(100)-hex surface reconstruction in the presence of CO, H₂, and Benzene. The gas adsorption and subsequent charge transfer relieves the surface strain caused by the low coordination number of the (100) surface atoms allowing the formation of a (1 x 1) surface structure commensurate with the bulk terminated crystal structure. The surface phase change causes a transformation of the surface layer from hexagonal packing geometry to a four-fold symmetric surface which is rich in atomic defects. Lifting the hex reconstruction at room temperature resulted in a surface structure decorated with 2-3 nm Pt adatom islands with a high density of step edge sites. Annealing the surface at a modest temperature (150 C) in the presence of a high pressure of CO or H₂ increased the surface diffusion of the Pt atoms causing the adatom islands to aggregate reducing the surface concentration of low coordination defect sites. Ethylene hydrogenation was studied on the Pt(100) surface using HP-STM. At low pressure, the lifting of the hex reconstruction was observed in the STM images. Increasing the ethylene pressure to 1 Torr, was found to regenerate the hexagonally symmetric reconstructed phase. At room temperature ethylene undergoes a structural rearrangement to form ethylidyne. Ethylidyne preferentially binds at the three-fold hollow sites, which

A perspective on two chemometrics tools: PCA and MCR, and introduction of a new one: Pattern recognition entropy (PRE), as applied to XPS and ToF-SIMS depth profiles of organic and inorganic materials

Science.gov (United States)

Chatterjee, Shiladitya; Singh, Bhupinder; Diwan, Anubhav; Lee, Zheng Rong; Engelhard, Mark H.; Terry, Jeff; Tolley, H. Dennis; Gallagher, Neal B.; Linford, Matthew R.

2018-03-01

X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) are much used analytical techniques that provide information about the outermost atomic and molecular layers of materials. In this work, we discuss the application of multivariate spectral techniques, including principal component analysis (PCA) and multivariate curve resolution (MCR), to the analysis of XPS and ToF-SIMS depth profiles. Multivariate analyses often provide insight into data sets that is not easily obtained in a univariate fashion. Pattern recognition entropy (PRE), which has its roots in Shannon's information theory, is also introduced. This approach is not the same as the mutual information/entropy approaches sometimes used in data processing. A discussion of the theory of each technique is presented. PCA, MCR, and PRE are applied to four different data sets obtained from: a ToF-SIMS depth profile through ca. 100 nm of plasma polymerized C3F6 on Si, a ToF-SIMS depth profile through ca. 100 nm of plasma polymerized PNIPAM (poly (N-isopropylacrylamide)) on Si, an XPS depth profile through a film of SiO2 on Si, and an XPS depth profile through a film of Ta2O5 on Ta. PCA, MCR, and PRE reveal the presence of interfaces in the films, and often indicate that the first few scans in the depth profiles are different from those that follow. PRE and backward difference PRE provide this information in a straightforward fashion. Rises in the PRE signals at interfaces suggest greater complexity to the corresponding spectra. Results from PCA, especially for the higher principal components, were sometimes difficult to understand. MCR analyses were generally more interpretable.

XPS\\KOUADIO KOUASSI.xps

African Journals Online (AJOL)

HP Pro 2000

éclaircie dans les impénétrables régénérations de chêne. Dans la forêt tropicale guyanaise, Guitet et al. (2009) ont montré que l'application mixte des éclaircies sélective et systématique a permis une forte croissance en diamètre des tiges des ...

Study of the temperature dependent nitrogen retention in tungsten surfaces by XPS-analysis

Energy Technology Data Exchange (ETDEWEB)

Plank, Ulrike [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany); Fakultaet fuer Physik der Ludwig-Maximilians-Universitaet Muenchen, Schellingstrasse 4, D-80799 Muenchen (Germany); Meisl, Gerd; Hoeschen, Till [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)

2016-07-01

To reduce the power load on the divertor of fusion experiments, nitrogen (N) is puffed into the plasma. As a side effect, nitrogen gets implanted into the tungsten (W) walls of the reactor and forms nitride layers. Their formation and, therefore, the N accumulation in W showed an unexpected temperature dependence in previous experiments. To study the nitrogen retention, we implanted N ions with an energy of 300 eV into W and observed the evolution of the surface composition by X-ray photoelectron spectroscopy (XPS). We find that the N content does not change when the sample is annealed up to 800 K after implantation at lower temperatures. In contrast, the N concentration decreases with increasing implantation temperature. At 800 K implantation temperature, the N saturation level is about 5 times lower compared to 300 K implantation. A possible explanation for this difference is an enhanced diffusion during ion bombardment due to changes in the structure or in the chemical state of the tungsten nitride system. Ongoing tungsten nitride erosion experiments shall help to clarify whether the strong temperature dependence is the result of enhanced diffusion or of phase changes.

An XPS study of pulsed plasma polymerised allyl alcohol film growth on polyurethane

Energy Technology Data Exchange (ETDEWEB)

Watkins, Lucy [Department of Chemistry, University of York, Heslington, York YO10 5DD (United Kingdom); Bismarck, Alexander [Department of Chemical Engineering, Polymer and Composite Engineering (PaCE) Group, Imperial College London, London SW7 2AZ (United Kingdom); Lee, Adam F. [Department of Chemistry, University of York, Heslington, York YO10 5DD (United Kingdom); Wilson, Darren [Smith and Nephew Research Centre, York Science Park, Heslington, York YO10 5DF (United Kingdom); Wilson, Karen [Department of Chemistry, University of York, Heslington, York YO10 5DD (United Kingdom)]. E-mail: kw13@york.ac.uk

2006-09-30

The growth of highly functionalised poly allyl alcohol films by pulsed plasma polymerisation of CH{sub 2} =CHCH{sub 2}OH on biomedical grade polyurethane has been followed by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. Film thickness is observed to increase approximately linearly with plasma modification time, suggesting a layer-by-layer growth mode of poly allyl alcohol. Water contact angle measurements reveal the change in the surface free energy of wetting decreases linearly with plasma modification up to the monolayer point after which a constant limiting value of -24 mJ m{sup -2} was attained. Films prepared at 20 W plasma power with a duty cycle of 10 {mu}s:500 {mu}s exhibit a high degree of hydroxyl (-OH) retention with minimal fragmentation of the monomer observed. Increasing the plasma power up to 125 W is found to improve -OH retention at the expense of ether formation generating films close to the monomer stoichiometry. Duty cycle plays an important role in controlling both film composition and thickness, with longer off times increasing -OH retention, while longer on times enhance allyl alcohol film growth.

Surface science approach to Pt/carbon model catalysts: XPS, STM and microreactor studies

Science.gov (United States)

Motin, Abdul Md.; Haunold, Thomas; Bukhtiyarov, Andrey V.; Bera, Abhijit; Rameshan, Christoph; Rupprechter, Günther

2018-05-01

Pt nanoparticles supported on carbon are an important technological catalyst. A corresponding model catalyst was prepared by physical vapor deposition (PVD) of Pt on sputtered HOPG (highly oriented pyrolytic graphite). The carbon substrate before and after sputtering as well as the Pt/HOPG system before and after Pt deposition and annealing were examined by XPS and STM. This yielded information on the surface density of defects, which serve as nucleation centres for Pt, and on the size distribution (mean size/height) of the Pt nanoparticles. Two different model catalysts were prepared with mean sizes of 2.0 and 3.6 nm, both turned out to be stable upon UHV-annealing to 300 °C. After transfer into a UHV-compatible flow microreactor and subsequent cleaning in UHV and under mbar pressure, the catalytic activity of the Pt/HOPG model system for ethylene hydrogenation was examined under atmospheric pressure flow conditions. This enabled to determine temperature-dependent conversion rates, turnover frequencies (TOFs) and activation energies. The catalytic results obtained are in line with the characteristics of technological Pt/C, demonstrating the validity of the current surface science based model catalyst approach.

Chemistry Characterization of Jet Aircraft Engine Particulate by XPS: Results from APEX III

Science.gov (United States)

Vander Wal, Randy L.; Bryg, Victoria M.

2014-01-01

This paper reports XPS analysis of jet exhaust particulate from a B737, Lear, ERJ, and A300 aircraft during the APEX III NASA led field campaign. Carbon hybridization and bonding chemistry are identified by high-resolution scans about the C1s core-shell region. Significant organic content as gauged by the sp3/sp2 ratio is found across engines and platforms. Polar oxygen functional groups include carboxylic, carbonyl and phenol with combined content of 20 percent or more. By lower resolution survey scans various elements including transition metals are identified along with lighter elements such as S, N, and O in the form of oxides. Burning additives within lubricants are probable sources of Na, Ba, Ca, Zn, P and possibly Sn. Elements present and their percentages varied significantly across all engines, not revealing any trend or identifiable cause for the differences, though the origin is likely the same for the same element when observed. This finding suggests that their presence can be used as a tracer for identifying soots from aircraft engines as well as diagnostic for monitoring engine performance and wear.

Caracterização tecnológica de cookies produzidos com diferentes concentrações de farinha de algaroba durante armazenamento por 120 dias

Directory of Open Access Journals (Sweden)

Rennan Pereira de Gusmão

2018-02-01

Full Text Available Resumo O objetivo deste trabalho foi avaliar os parâmetros de qualidade (firmeza, fraturabilidade, atividade de água e cor de biscoitos enriquecidos com diferentes percentuais de farinha de algaroba (5%, 15% e 25%, durante o armazenamento por 120 dias, além de determinar as características físicas (espessura, diâmetro, fator de expansão, volume específico e massa, físico-químicas (teor de água, cinzas, proteínas, açúcares, lipídios e fibras e minerais (cálcio, fósforo e ferro. Os parâmetros de qualidade desses produtos foram acompanhados durante 120 dias de armazenamento, com intervalo de 15 dias entre as medições. Foram realizadas as caracterizações física e físico-química, e os minerais foram determinados por espectroscopia de difração de raios X por energia dispersiva. Os parâmetros de qualidade foram analisados estatisticamente, utilizando-se um delineamento experimental fatorial, com dois fatores: nove períodos de armazenamento e três formulações de biscoitos. Conclui-se que, após o período de 120 dias de armazenamento, houve diferença significativa entre os parâmetros de qualidade dos biscoitos. Os biscoitos elaborados com farinha de algaroba tiveram sua atividade de água, fraturabilidade e luminosidade aumentada, e sua firmeza e intensidade de amarelo e vermelho, reduzidas. Com o aumento da concentração de farinha de algaroba na formulação dos biscoitos, ocorreu uma variação maior entre a atividade de água inicial e a atividade de água final, e entre luminosidade inicial e luminosidade final. Os biscoitos enriquecidos com farinha de algaroba apresentaram nutrientes, como cálcio, ferro e fósforo, e características de qualidade aceitáveis durante o armazenamento, com comportamento similar a produtos já existentes no mercado.

Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

Science.gov (United States)

Lou, Leo; Nelson, Alan E.; Heo, Giseon; Major, Paul W.

2008-08-01

The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found ( p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength.

Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

Energy Technology Data Exchange (ETDEWEB)

Lou, Leo [Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta (Canada); Nelson, Alan E. [Department of Chemical and Materials Engineering, University of Alberta (Canada)], E-mail: aenelson@dow.com; Heo, Giseon [Department of Statistics, Department of Dentistry, University of Alberta (Canada); Major, Paul W. [Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta (Canada)

2008-08-30

The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found (p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength.

Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

International Nuclear Information System (INIS)

Lou, Leo; Nelson, Alan E.; Heo, Giseon; Major, Paul W.

2008-01-01

The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found (p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength

Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology.

Science.gov (United States)

Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

2016-04-01

Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Por entre as linhas: imaginário, saberes e fazeres docente = Between the lines: imagination, knowledge and teachers practices

Directory of Open Access Journals (Sweden)

Voos, Jordelina Beatriz Anacleto

2014-01-01

Full Text Available Este artigo trata de uma experiência, na prática de pesquisa em educação sobre o exercício de reflexão de um professor de educação física, referente à sua prática, mediante o registro de atividades. À luz dos procedimentos da Análise de Conteúdo, referencial construído por Bardin (2002, foram analisados os textos de oito diários de classe. Emergiram muitos elementos sobre a prática do professor, dentre eles, destacou-se o significado do espaço físico escolar e a relação, desse espaço, com os saberes e fazeres docentes, trazidos pelo seu autor. Ao analisar os textos dos diários, isto é, apreender, pela e na narração, o que o professor pensa, sente, sabe e faz, enquanto profissional, incorpora-se à interlocução a produção de texto fundamentador, como possibilidade de traduzir, teoricamente, os posicionamentos do pesquisado, produtores de sentido, implícitos e/ ou explícitos na reflexão. Esse exercício, realizado (análise, interpretação e interlocução mediadas, pela devida fundamentação teórica constituiu o processo de investigação

XPS and GDOES Characterization of Porous Coating Enriched with Copper and Calcium Obtained on Tantalum via Plasma Electrolytic Oxidation

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Krzysztof Rokosz

2016-01-01

Full Text Available XPS and GDOES characterizations of porous coatings on tantalum after Plasma Electrolytic Oxidation (PEO at 450 V for 3 minutes in electrolyte containing concentrated (85% phosphoric acid with calcium nitrate and copper (II nitrate are described. Based on the obtained data, it may be concluded that the PEO coating consists of tantalum (Ta5+, calcium (Ca2+, copper (Cu2+  and Cu+, and phosphates (PO43-. It has to be pointed out that copper and calcium are distributed throughout the volume. The authors also propose a new model of PEO, based on the derivative of GDOES signals with sputtering time.

Utilization of the statistics techniques for the analysis of the XPS (X-ray photoelectron spectroscopy) and Auger electronic spectra's deconvolutions

International Nuclear Information System (INIS)

Puentes, M.B.

1987-01-01

For the analysis of the XPS (X-ray photoelectron spectroscopy) and Auger spectra, it is important to performe the peaks' separation and estimate its intensity. For this purpose, a methodology was implemented, including: a spectrum's filter; b) substraction of the base line (or inelastic background); c) deconvolution (separation of the distribution that integrates the spectrum) and d) error of calculation of the mean estimation, comprising adjustment quality tests. A software (FORTRAN IV plus) that permits to use the methodology proposed from the experimental spectra was implemented. The quality of the methodology was tested with simulated spectra. (Author) [es

Porøse materialer

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2000-01-01

Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

LEVANTAMENTO EPIDEMIOLÓGICO DE INFECÇÃO POR ACINETOBACTER SPP EM AMOSTRAS DE HEMOCULTURAS DE UM LABORATÓRIO DE SÃO JOSÉ DOS CAMPOS

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Vânia Waleska Sousa da Cunha

2015-01-01

Full Text Available A presença de infecções na corrente sanguínea representa uma grave complicação na situação de pacientes críticos, podendo aumentar os riscos de morbidade e mortalidade, sendo a hemocultura um importante recurso no diagnóstico do agente microbiano. Entre as bactérias causadoras de bacteriemia, encontramos, frequentemente, a Acinetobacter spp, sendo um patógeno de grande importância clínica devido ao aumento de sua frequência como causa de infecções hospitalares e, também, por, normalmente, apresentar multirresistência aos agentes antimicrobianos de prática clínica. O presente estudo teve como finalidade o levantamento epidemiológico de infecções em hemoculturas causadas pelo gênero Acinetobacter spp em pacientes internados, em hospitais de São José dos Campos-SP, demonstrando sua prevalência no munícipio. Os dados analisados foram fornecidos pelo sistema de um laboratório de análises microbiológicas e utilizados para o levantamento de infecções por Acinetobacter spp em hemoculturas, no período de agosto de 2012 a agosto de 2013. Foram avaliados 5.759 exames de hemocultura, com 1.019 resultados positivos, sendo que Acinetobacter baumannii foi identificada em 31 amostras, correspondendo ao sexto patógeno mais isolado (3,04% das hemoculturas positivas. A. baumannii se tornou um patógeno de grande preocupação hospitalar, devido à sua crescente colonização nas Unidades de Tratamento Intensivo e sua multirresistência aos antimicrobianos.

Difference in surface reactions between titanium and zirconium in Hanks' solution to elucidate mechanism of calcium phosphate formation on titanium using XPS and cathodic polarization

International Nuclear Information System (INIS)

Tsutsumi, Y.; Nishimura, D.; Doi, H.; Nomura, N.; Hanawa, T.

2009-01-01

Titanium and zirconium were immersed in Hanks' solution with and without calcium and phosphate ions, and the surfaces were characterized with X-ray photoelectron spectroscopy (XPS) to determine the mechanism of calcium phosphate formation on titanium in simulated body fluids and in a living body. In addition, they were cathodically polarized in the above solutions. XPS characterization and cathodic polarization revealed differences in the surface properties in the ability of calcium phosphate formation between titanium and zirconium. The surface oxide film on titanium is not completely oxidized and is relatively reactive; that on zirconium is more passive and protective than that on titanium. Neither calcium nor phosphate stably exists alone on titanium, and calcium phosphate is naturally formed on it; calcium phosphate formed on titanium is stable and protective. On the other hand, calcium is never incorporated on zirconium, while zirconium phosphate, which is easily formed on zirconium, is highly stable and protective. Our study presents new information regarding the surface property of titanium and demonstrates that the characteristics of titanium and zirconium may be applied to various medical devices and new surface modification techniques.

Gerenciamento de medicamentos em desuso devolvidos por pacientes ambulatoriais de um hospital universitário

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Lilian Pereira Primo

2014-04-01

Full Text Available O presente trabalho teve como objetivo avaliar o perfil das devoluções de medicamentos não utilizados à farmácia do Componente Especializado da Assistência Farmacêutica do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, da Universidade de São Paulo, bem como o perfil de sua destinação final. Tratase de um estudo transversal e descritivo que teve como ferramenta a coleta dos seguintes dados: identificação do paciente ou responsável, motivo da devolução e dados dos medicamentos devolvidos (lote, validade, quantidade devolvida e condições de armazenamento. Realizou-se a análise dos dados por meio de avaliação do questionário aplicado e, além disso, avaliou-se o aspecto visual dos medicamentos devolvidos que foram classificados como aptos para reuso por outros pacientes ou enviados para descarte. Os custos relacionados com as devoluções à instituição foram calculados e analisados. A coleta de dados foi realizada no mês de julho de 2011. Durante este período, foram recebidas 34 devoluções, correspondendo a 2149 unidades de medicamentos. Destes, 82,4% estavam íntegros, 6,0% eram termolábeis e apenas 3,0% estavam vencidos, sendo reaproveitados 76,5% de todos os medicamentos. O valor financeiro do total dos itens devolvidos foi de R$ 5.759,90 e a economia com o repasse a outros pacientes representou R$ 4.743,34. O estímulo à devolução a partir da implementação de um sistema de gerenciamento de medicamentos efetivo oferece segurança ao paciente e ao meio ambiente e economia ao sistema de saúde. Para que isso ocorra, a equipe de saúde deve estar capacitada a orientar sobre o armazenamento correto a fim de garantir a integridade e qualidade do princípio ativo, visando um resultado terapêutico ótimo àqueles pacientes que reutilizarem os mesmos.

Adição de soro de leite e café na qualidade do doce de leite pastoso

OpenAIRE

Ferreira,Larissa de Oliveira; Pimenta,Carlos José; Santos,Gabriella; Ramos,Thaís de Melo; Pereira,Patrícia Aparecida Pimenta; Pinheiro,Ana Carla Marques

2012-01-01

Este trabalho foi realizado com o objetivo de verificar o efeito da substituição de leite por soro de leite e o efeito da adição de café na qualidade química e sensorial do doce de leite. Foi utilizado um fatorial completo 2², com dois níveis (±1) com a adição de três pontos centrais (0) e dois níveis de pontos axiais (±1,41). Os resultados obtidos foram analisados pela metodologia estatística de superfície de resposta e os dados do teste de aceitação foram analisados pela metodologia de mapa...

E-Commerce no Brasil: Se o Segmento é Promissor, Por Que Empresas Atuantes Estão no Vermelho?

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Adriana Serafim dos Santos

2015-04-01

Full Text Available A mudança de perfil dos novos consumidores tem exigido das organizações inovação em suas operações. Nesse contexto, uma nova modalidade de negócios tem modificado o cenário brasileiro, o e-commerce. Este segmento está em pleno crescimento, com projeções elevadas de faturamento (EBIT, 2013. No entanto, um paradoxo tem intrigado pesquisadores da área. Se o segmento é promissor, por que as empresas do ramo têm resultados negativos? Diante disso, o objetivo do estudo foi verificar o que revela a análise das demonstrações contábeis sobre o desempenho econômico-financeiro da B2W Digital (que atua no varejo on-line em comparação com outras empresas classificadas no mesmo setor na BM&FBovespa (atuantes no varejo tradicional. Na plataforma teórica foram discutidos os principais indicadores financeiros e econômicos e apresentado um histórico sobre o e-commerce no Brasil. Posteriormente foi realizada análise documental nas demonstrações contábeis das referidas empresas no período de 2007 a 2012. Foi constatado que as principais causas para o baixo desempenho da B2W Digital no período analisado foram: desequilíbrio na gestão dos prazos médios, ou seja, a organização paga seus fornecedores em prazos bem menores do que recebe de seus clientes, por isso a necessidade de financiar sua operação com recursos onerosos de curto prazo, principalmente empréstimos e antecipações de recebíveis, o que acarreta em despesas com taxas e juros; elevado grau de endividamento; baixa margem bruta, devido ao custo da mercadoria vendida que consome mais de 70% de sua receita líquida; e, finalmente, aumento das despesas operacionais, principalmente em distribuição.

Verdad por definición

OpenAIRE

Garrido Garrido, Julián

1997-01-01

Not available.La verdad por definición es un tipo peculiar de verdad científica, distinguible de las verdades lógicas, matemáticas y empíricas. La definición, por su parte, designa diversos procedimientos de asignación de significado, cuyas diferencias exigen una adjetivación cuidadosa: definiciones ostensivas y operacionales, definiciones de diccionario y definiciones teóricas. Pero sólo las del último tipo son verdaderas por definición. En el presente artículo se precisa el concepto formal ...

Remoção da fração oleosa de embalagens de lubrificantes automotivos pós-consumo por drenagem gravitacional

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Harley Moraes Martins

Full Text Available RESUMO: Este trabalho aborda a questão do gerenciamento de embalagens pós-consumo de lubrificantes automotivos, considerando as dificuldades inerentes à implementação do sistema de logística reversa - prática compulsória por força de lei (Brasil, Lei 12.305/2010 - e a ineficácia dos atuais métodos utilizados para remoção da fração oleosa residual, necessária ao reprocessamento do material plástico por reciclagem mecânica direta. Para determinar metodologia apropriada para limpeza dos frascos de lubrificantes foram conduzidos experimentos para avaliar a influência do aquecimento e da posição das embalagens durante o processo de drenagem gravitacional. O procedimento analítico realizado proporcionou a escolha de uma combinação de variáveis capaz de assegurar remoção de elevado teor do resíduo oleoso com menor gasto energético. A otimização foi feita utilizando um planejamento experimental do tipo composto central com triplicata no ponto central. Os dados obtidos nos ensaios foram analisados com recursos estatísticos e demonstraram que ambos os parâmetros avaliados interferem, de forma significativa, no processo em estudo. Os resultados apontaram aumento da eficácia do processo quando a drenagem é realizada em temperaturas superiores a 35ºC e com a embalagem inclinada em ângulos próximos a 70º em relação à horizontal. Nessas condições, percentuais de remoção de óleo residual superaram 95% após 35 minutos de drenagem.

XPS study of Li/Nb ratio in LiNbO{sub 3} crystals. Effect of polarity and mechanical processing on LiNbO{sub 3} surface chemical composition

Energy Technology Data Exchange (ETDEWEB)

Skryleva, E.A., E-mail: easkryleva@gmail.com; Kubasov, I.V., E-mail: kubasov.ilya@gmail.com; Kiryukhantsev-Korneev, Ph.V., E-mail: kiruhancev-korneev@yandex.ru; Senatulin, B.R., E-mail: borisrs@yandex.ru; Zhukov, R.N., E-mail: rom_zhuk@mail.ru; Zakutailov, K.V., E-mail: zakkonst@gmail.com; Malinkovich, M.D., E-mail: malinkovich@yandex.ru; Parkhomenko, Yu.N., E-mail: parkh@rambler.ru

2016-12-15

Highlights: • XPS Li/Nb ratio measurement uncertainty in LNbO3 specimens was obtained. • The effect of polarization on surface chemistry was observed only on cleaves. • Li/Nb ratio on positive cleave surface is higher than on negative one. • The positive cleave surface adsorbs fluorine more efficiently than negative one. • Mechanical processing of crystals reduces surface Li/Nb. - Abstract: Different sections of congruent lithium niobate (CLN) crystals have been studied using X-ray photoelectron spectroscopy (XPS). We have developed a method for measuring the lithium-to-niobium atomic ratio Li/Nb from the ratio of the Li1s and Nb4s spectral integral intensities with an overall error of within 8 %. Polarity and mechanical processing affect the Li/Nb ratio on CLN crystal surfaces. The Li/Nb ratio is within the tolerance (0.946 ± 0.074) on the negative cleave surface Z, and there is excess lithium (Li/Nb = 1.25 ± 0.10) on the positive surface. The positive surfaces of the 128° Y cut plates after long exposure to air exhibit LiOH formation indications (obvious lithium excess, higher Li1s spectral binding energy and a wide additional peak in the O1s spectrum produced by nonstructural oxygen). XPS and glow discharge optical electron spectroscopy showed that mechanical processing of differently oriented crystals (X, Z and 128° Y) and different polarities dramatically reduces the Li/Nb ratio. In situ fluorine adsorption experiments revealed the following regularities: fluorine adsorption only occurred on crystal cleaves and was not observed for mechanically processed specimens. Positive cleave surfaces have substantially higher fluorine adsorption capacity compared to negative ones.

Electrocardiografo por computadora

OpenAIRE

Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

2009-01-01

El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

ANÁLISE ESPACIAL DA TEMPERATURA E DA PRECIPITAÇÃO MEDIA ANUAL NO ESTADO DE SÃO PAULO / SPATIAL ANALYSIS OF MEAN ANNUAL TEMPERATURE AND RAINFALL FOR THE SÃO PAULO STATE

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SIDNEY R. VIEIRA

2009-11-01

Full Text Available O objetivo deste trabalho foi analisar a variabilidade espacial da temperatura e da precipitação média anual no Estado de São Paulo. Foram utilizados dados de 416 estações climatológicas, referente ao período de 1936 a 1992 e analisados dois parâmetros climatológicos (temperatura média anual e precipitação pluvial média anual. Os dados foram analisados por meio da estatística descritiva e dageoestatística, para posterior construção de mapas de variabilidade espacial. Os resultados evidenciam que a altitude (m e a temperatura média anual (ºC apresentaram baixos valores de efeito pepita enquanto que a precipitação pluvial média anual (mm apresentou um maior pra esseparâmetro. A temperatura média anual (ºC e a precipitação pluvial média anual (mm apresentaram periodicidade detectada por meio do semivariograma experimental. Os mapas de distribuição espacial evidenciam a influencia da altitude sobre os valores estimados por krigagem para temperatura médiaanual (ºC e precipitação pluvial média anual (mm.

Análise comparativa entre a refração clínica subjetiva e a automatizada obtida por sensor de frentes de onda Comparative analyses between clinical refraction and automatic refraction obtained through a wave front sensor

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Wilson de Freitas

2007-08-01

Full Text Available OBJETIVO: Avaliar e comparar os resultados obtidos da refração estática clínica com a obtida por sensor de frentes de onda. MÉTODOS: Estudo prospectivo, não seqüencial, de 279 olhos de 147 pacientes. Todos os pacientes foram examinados sob cicloplegia. Primeiro realizamos a refração clínica e a seguir a automatizada por sensor de frentes de onda. Os dados refracionais obtidos foram decompostos para análise vetorial. Foram analisados separadamente os dados de um olho por paciente e dos dois olhos. RESULTADOS: A diferença entre a refração clínica e a automatizada foi de -0,19 DE combinada com -0,06 DC no eixo de 15º para os dados de um olho por paciente e -0,17 DE combinada com -0,05 DC no eixo de 3º para todos os olhos da amostra. CONCLUSÃO: Os dados da refração clínica são comparáveis com os da refração obtida por um sensor de frentes de onda.PURPOSE: To evaluate and compare refractive errors obtained through clinical subjective and automatized wavefront refraction analyses in eyes under cycloplegia. METHODS: Prospective study of 147 patients, 279 eyes, undergoing preoperative examination for refractive surgery. Clinical subjective refraction was performed first followed by wavefront refraction. Results on astigmatism obtained from refraction were decomposed in power vectors for statistical analyses. Data were first analyzed in one eye and then in both eyes. RESULTS: The mean difference between clinical subjective refraction and automatized wavefront refraction on cycloplegic eyes was of -0.19 SD combined with -0.06 CD in the 15º axis for data in one eye, and -0.17 SD combined with -0.05 CD in the 3º axis for data in both eyes of the same patient. CONCLUSION: In the present study clinical subjective refraction and automatized wavefront refraction under cycloplegia had similar numerical values.

Significados de violência familiar contra o idoso na perspectiva de profissionais da Atenção Primária à Saúde

OpenAIRE

Wanderbroocke,Ana Claudia Nunes de Souza; Moré,Carmen Leontina Ojeda Ocampo

2012-01-01

O presente estudo de cunho qualitativo buscou analisar os significados atribuídos à violência familiar contra o idoso, por profissionais que atuam na atenção primária à saúde. Participaram 10 profissionais com diferentes formações, de uma unidade de saúde de referencia para idosos, sendo os dados coletados por meio de entrevistas semiestruturadas e analisados segundo os princípios da Grounded Theory. Os dados foram integrados e organizados em categorias, subcategorias e elementos de análise. ...

Adolescência em Conflito com a Lei: A Intensidade da História de Vida em Ato

OpenAIRE

Tomasi,Laura Oliveira; Macedo,Mônica Medeiros Kother

2015-01-01

A pesquisa aborda o ato infracional a partir da história de vida de adolescentes em conflito com a lei e dos significados atribuídos por eles aos atos cometidos. Realizaram-se entrevistas semiestruturadas com quatro adolescentes com processo judicial em andamento devido a atos transgressivos. Os dados foram analisados por meio da Análise de Conteúdo e interpretados com aportes da Psicanálise. Quatro categorias finais constataram, na história de vida dos jovens, vivências extremas e recorrente...

Extração e quantificação de alumínio trocável em Organossolos

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José Ricardo da Rocha Campos

2014-03-01

Full Text Available O objetivo deste trabalho foi avaliar diferentes métodos de extração e quantificação de alumínio trocável em Organossolos. As amostras foram coletadas em três perfis de turfeira e, então, secas ao ar e passadas em peneira de malha de 2 mm. Foram feitas extrações com KCl 1 mol L-1 , Ca(OAc2 1 mol L-1 e CuCl2 0,5 mol L-1 . Em seguida, os extratos obtidos por KCl e Ca(OAc2 foram analisados por titulação com NaOH 0,025 mol L-1 e por espectrômetro de absorção atômica com forno de grafite (GF-AAE. Os extratos obtidos por CuCl2 foram analisados por GF-AAE. Na quantificação por GF-AAE, os extratores KCl e Ca(OAc2 tiveram capacidade semelhante de extrair alumínio trocável, enquanto o CuCl2 foi capaz de extrair também o Al reativo. Os elevados teores de alumínio trocável observados na titulação após extração com KCl podem estar relacionados aos elevados teores do íon H+ presente nas amostras. O método indicado para determinação do teor de alumínio trocável em Organossolos é a extração com KCl ou com Ca(OAc2 e, para quantificação, a espectrofotometria de absorção atômica com forno de grafite.

XPS study of surface state of novel perovskite system Dy{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3-δ} as cathode for solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Kautkar, Pranay R.; Acharya, Smita A., E-mail: saha275@yahoo.com; Tumram, Priya V. [Depatment of Physics, Rashtrasant Tukadoji Maharaj Nagpur University Campus, Nagpur-440033 (India); Deshpande, U. P. [UGC-DAE Consortium for scientific Research, University Campus, Khandwa Road, Indore-452001, Madhya Pradesh,India (India)

2016-05-06

In the present attempt,novel perovskite oxide Dy{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3–δ} (DSCF) as cathode material has been synthesized by an Ethylene glycol-citrate combined sol-gel combustion route. Orthorhombic symmetry structure is confirmed by X-ray diffraction (XRD) and data is well fitted using Rietveld refinement by Full-Prof software suite. Chemical natureof surface of DSCF has been analyzed by using X-ray photoelectron spectroscopy (XPS). XPS result shows that Dy ions are in +3 oxidation state and Sr in +2 states. However Co2p and Fe2p spectra indicates partial change in oxidation state from Co3+/Fe3+ to Co4+/Fe4+. These attribute to develop active sites on the surface for oxygen ions. O1s XPS spectra shows two oxygen peaks relatedto lattice oxygen in perovskite and absorbed oxygen in oxygen vacancy are detected. O1s spectra demonstrate the existence of adsorbed oxygen species on the surface of DSCF oxide which is quite beneficial for intermediate temperature of Solid Oxide Fuel Cell.

XPS and NRA investigations during the fabrication of gold nanostructured functionalized screen-printed sensors for the detection of metallic pollutants

Science.gov (United States)

Jasmin, Jean-Philippe; Miserque, Frédéric; Dumas, Eddy; Vickridge, Ian; Ganem, Jean-Jacques; Cannizzo, Caroline; Chaussé, Annie

2017-03-01

An all covalent nanostructured lead sensor was built by the successive grafting of gold nanoparticles and carboxylic ligands at the surface of self-adhesive carbon screen-printed electrodes (SPEs). Surface analysis techniques were used in each step in order to investigate the structuration of this sensor. The self-adhesive surfaces were made from the electrochemical grafting of p-phenylenediamine at the surface of the SPEs via diazonium salts chemistry. The quantity of grafted aniline functions, estimated by Nuclear Reaction Analysis (NRA) performed with p-phenylenediamine labelled with 15N isotope, is in agreement with an almost complete coverage of the electrode surface. The subsequent diazotization of the aniline functions at the surface of the SPEs was performed; X-ray Photoelectron Spectroscopy (XPS) allowed us to consider a quantitative conversion of the aniline functions into diazonium moieties. The spontaneous grafting of gold nanoparticles on the as-obtained reactive surfaces ensures the nanostructuration of the material, and XPS studies showed that the covalent bonding of the gold nanoparticles at the surface of the SPEs induces a change both in the Au-4f (gold nanoparticles) and Cl-2p (carbon ink) core level signals. These unusual observations are explained by an interaction between the carbon ink constituting the substrate and the gold nanoparticles. Heavy and toxic metals are considered of major environmental concern because of their non-biodegradability. In a final step, the grafting of the carboxylic ligands at the surface of the SPEs and an accumulation step in the presence of lead(II) cations allowed us to evidence the interest of nanostructured materials as metallic pollutants sensors.

XPS-UPS, ISS characterization studies and the effect of Pt and K addition on the catalytic properties of MoO2-x(OH)y deposited on TiO2

International Nuclear Information System (INIS)

Al-Kandari, H.; Mohamed, A.M.; Al-Kharafi, F.; Katrib, A.

2011-01-01

Highlights: → Surface electronic structure-catalytic activity correlation is presented in this research work. → In situ characterization by XPS-UPS and ISS techniques were employed at the same experimental conditions applied for catalytic reactions. → Catalytic reactions of Mo deposited on titanium oxide for the isomerization and hydrogenation reactions using 1-hexene and n-hexane were studied. → The bifunctional properties of the molybdenum dioxide phase were modified by the addition of potassium. - Abstract: Characterization by XPS-UPS, ISS surface techniques of MoO 3 /TiO 2 catalysts before and after addition of Pt (PtMo) 2.5% by weight of MoO 3 and potassium (KMo) enabled to identify different chemical species present on the outermost surface layer at different reduction temperatures. Catalytic activities of these systems using 1-hexene and n-hexane reactants were studied. Correlation between catalytic activity and surface electronic structure enabled us to identify the chemical species, active site(s), responsible for specific catalytic reaction(s).

Mudança de marca: o rebranding da Algar Telecom

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Lucas Borges Kappel

2016-03-01

Full Text Available As alterações nas marcas (rebranding podem impactar consumidores e organizações. O objeto de estudo é a empresa CTBC, que está passando pelo processo de rebranding para Algar Telecom. São descritos e analisados os impactos organizacionais dessa mudança da marca segundo o modelo proposto por Muzellec e Lambkin (2006, no qual foram identificados fatores ligados à necessidade de realização do rebranding, objetivos destas mudanças e processos. Por intermédio do estudo de caso, com triangulação de dados (entrevistas individuais, análise de documentos e análise de registros em arquivos, os dados foram analisados segundo a técnica de análise de conteúdo (BARDIN, 1977 e pela técnica snowball sampling (BIERNACKI, WALDORF, 1981. Identificou-se como fator do rebranding a mudança na estratégia corporativa; como objetivo do rebranding, a reflexão de uma nova marca e a sua revolução; e, como o processo de rebranding, o foco nos colaboradores.

Comparação Entre Os Modelos Residual Income Valuation (RIV, Abnormal Earnings Growth (AEG e Fluxo de Caixa Livre (FCF: Um estudo empírico no mercado de capitais brasileiro

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Eric Serrano Ferreira

2008-01-01

Full Text Available O objetivo deste estudo foi comparar os modelos Residual Income Valuation (RIV, Abnormal Earnings Growth (AEG e Fluxo de Caixa Livre (FCF no mercado brasileiro. Fez-se um teste empírico para comparar os três modelos, utilizando dados das empresas listadas na BOVESPA e testando a afirmação para o mercado de capitais brasileiro. Cada modelo foi analisado por meio da técnica estatística de regressão múltipla, anualmente, observando assim o comportamento dos modelos ao longo dos anos de 1995 a 2002. Ao serem realizados os testes, pode-se concluir que, de 1995 à 1999, o modelo RIV possuía poder explicativo superior aos outros dois modelos e a partir de 2000, os modelos AEG e RIV se equivalem, ilustrando o desenvolvimento do mercado brasileiro nos últimos anos. O modelo FCF apresentou o menor poder explicativo em todos os anos analisados. Os resultados encontrados se confirmaram por meio da análise de dados em painel.

Infection rates of pentastomids on lizards in urban habitats in the Brazilian northeast Níveis de infecção por pentastomídeos em lagartos de habitats urbanos no nordeste brasileiro

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WO. Almeida

2008-11-01

Full Text Available The rates of pentastomid infections in the syntopic lizards Hemidactylus mabouia and Tropidurus hispidus inhabiting buildings at the Federal University of Paraiba, in João Pessoa, NE Brazil were examined. A total of 30 specimens of Hemidactylus mabouia and 55 specimens of Tropidurus hispidus were examined. The animals were sacrificed by freezing and then fixed and conserved in 70% alcohol. Analyses of the respiratory tract of Hemidactylus mabouia demonstrated that these lizards were infected by Raillietiella frenatus at a rate of 20% (6/30 with an average infection intensity of 1.33 ± 0.21, 1-2. None of the specimens of T. hispidus analyzed were infected. Hemidactylus mabouia and R. frenatus are of African origin and it is possible that there are specific relationships, or preferences, between these two species.Foram analisadas as taxas de infecção por pentastomídeos nos lagartos simpátricos Hemidactylus mabouia e Tropidurus hispidus, habitando prédios da Universidade Federal da Paraíba, em João Pessoa, Nordeste do Brasil. Para tanto, foram examinados 30 espécimes de Hemidactylus mabouia e 55 de Tropidurus hispidus. Os espécimes coletados foram eutanizados por congelamento, fixados e conservados em álcool 70%. A análise do trato respiratório dos Hemidactylus mabouia mostrou que estavam infectados por Raillietiella frenatus, com prevalência de 20% (6/30 e intensidade de infecção média de 1,33 ± 0,21, 1-2. Nenhum espécime de T. hispidus analisado estava infectado. Hemidactylus mabouia e R. frenatus possuem origem africana e é possível que haja alguma relação de especificidade ou preferência entre essas espécies.

Celulitis por citomegalovirus Cytomegalovirus cellulitis

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A. Ruiz Lascano

2002-12-01

Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation

O CONCEITO DE PSICOPATIA ANALISADO PELA CRIMINOLOGIA CRÍTICA

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Bruno dos Santos Silva

2015-01-01

Full Text Available The present investigation aims at the concept of psychopathy, from its creation, in the XIX century, to the authors who gave it the structure conceived by scientific community nowadays. Further, that concept will be analyzed by the means of some authors of the critical criminology. For that reason, this paper will employ Criminology concepts to interpret the conformation of the object psychopathy and the institutional consequences of its application.

Solar Ion Processing of Major Element Surface Compositions of Mature Mare Soils: Insights from Combined XPS and Analytical TEM Observations

Science.gov (United States)

Christoffersen, R.; Dukes, C.; Keller, L. P.; Baragiola, R.

2012-01-01

Solar wind ions are capable of altering the sur-face chemistry of the lunar regolith by a number of mechanisms including preferential sputtering, radiation-enhanced diffusion and sputter erosion of space weathered surfaces containing pre-existing compositional profiles. We have previously reported in-situ ion irradiation experiments supported by X-ray photoelectron spectroscopy (XPS) and analytical TEM that show how solar ions potentially drive Fe and Ti reduction at the monolayer scale as well as the 10-100 nm depth scale in lunar soils [1]. Here we report experimental data on the effect of ion irradiation on the major element surface composition in a mature mare soil.

A XPS study of the Mo effect on passivation behaviors for highly controlled stainless steels in neutral and alkaline conditions

International Nuclear Information System (INIS)

Mesquita, Thiago J.; Chauveau, Eric; Mantel, Marc; Nogueira, Ricardo P.

2013-01-01

The objective of this work is to study the effect of Mo additions on film passive properties of three different stainless steels (SS) types (austenitic, ferritic and duplex alloys). A comparison between Mo containing (3 wt% Mo) and free Mo (0 wt% Mo) grades of highly controlled laboratory heats was done considering their passive film formed in different aggressive conditions, from neutral to alkaline pH. The presence of oxidized Mo on the passive layer was confirmed by X-ray photoelectron Spectroscopy (XPS). The presence of Mo within the passive film improved the passivity breakdown potential for the duplex and ferritic SS, but seemed to have no effect for austenitic SS.

A XPS study of the Mo effect on passivation behaviors for highly controlled stainless steels in neutral and alkaline conditions

Energy Technology Data Exchange (ETDEWEB)

Mesquita, Thiago J., E-mail: thiago.mesquita@ugitech.com [Ugitech Research Center, Avenue Paul Girod, 73403 Ugine Cedex (France); Chauveau, Eric; Mantel, Marc [Ugitech Research Center, Avenue Paul Girod, 73403 Ugine Cedex (France); Nogueira, Ricardo P. [LEPMI UMR 5279 CNRS – Grenoble INP–Université de Savoie–Université Joseph Fourier BP 75, 38402 St Martin d’Hères (France)

2013-04-01

The objective of this work is to study the effect of Mo additions on film passive properties of three different stainless steels (SS) types (austenitic, ferritic and duplex alloys). A comparison between Mo containing (3 wt% Mo) and free Mo (0 wt% Mo) grades of highly controlled laboratory heats was done considering their passive film formed in different aggressive conditions, from neutral to alkaline pH. The presence of oxidized Mo on the passive layer was confirmed by X-ray photoelectron Spectroscopy (XPS). The presence of Mo within the passive film improved the passivity breakdown potential for the duplex and ferritic SS, but seemed to have no effect for austenitic SS.

Desempenho de vacas Girolando mantidas em pastejo de Tifton 85 irrigado ou sequeiro

OpenAIRE

Teixeira, A.M.; Jayme, D.G.; Sene, G.A.; Fernandes, L.O.; Barreto, A.C.; Rodrigues Júnior, D.J.; Coutinho, A.C.; Glória, J.R.

2013-01-01

Objetivou-se com este trabalho avaliar a taxa de lotação e a produção de leite de vacas mestiças Holandês x Zebu em pastagens de Tifton 85 irrigadas e em sequeiro, em Uberaba-MG. Os dados foram analisados em um delineamento de blocos inteiramente ao acaso, com três repetições por tratamento, num esquema fatorial 2x10 (dois tratamentos e 10 épocas). Foi utilizado um lote de 11 vacas em lactação por tratamento para avaliação do desempenho animal. As médias foram comparadas por meio do teste de ...

Microstructure and electrical properties of slug-type resistors based on B4C and TiC - ESCA - XPS and impedance spectroscopy investigations

International Nuclear Information System (INIS)

Klimiec, E.; Zaraska, W.; Stobiecki, T.; Bak, W.; Starzyk, F.

2000-01-01

The microstructure and electrical properties of slug-type resistors based on B 4 C and TiC were investigated. From XPS measurements was deducted that Ti in TiO 2 is in intermediate oxidation number between Ti +4 and Ti +3 . The impedance of both type of resistors is independent on frequency in the range from 10 3 to 10 4 Hz, only very subtle differences above 10 4 Hz are observed. The metallic type conductivity in TiC and semiconducting in B 4 C was established. (author)

Tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional, 2000-2010

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Cristian A. Herrera Riquelme

2015-01-01

Full Text Available Objetivo. Caracterizar la tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional en el período 2000-2010 en la población mayor de 20 años. Métodos. Cálculo de las tasas de mortalidad específica por cáncer ajustadas por edad para diferentes niveles educacionales (NE, para el período 2000-2010. Las tasas obtenidas se analizaron con un modelo de regresión de Poisson, calculando el índice de desigualdad relativa (IDR y el índice de desigualdad de la pendiente (IDP para cada año. Resultados. Se registraron 232 541 muertes por cáncer en el período 2000-2010. Los tipos de cáncer más frecuentes fueron de mama, estómago y vesícula biliar en mujeres; y estómago, próstata y pulmón en hombres. Las tasas de mortalidad por cáncer estandarizadas por edad fueron mayores en los NE más bajos, excepto para el de mama en mujer y el de pulmón en hombres. Las mayores diferencias se encontraron en el de vesícula biliar en mujeres y el de estómago en hombres, con mayores tasas de mortalidad específica de hasta 49 y 63 veces respectivamente, para NE bajo respecto al NE alto. Entre 2000 y 2010, las diferencias en mortalidad por NE se redujeron para todos los cánceres combinados en ambos géneros, mama en mujeres, y pulmón y estómago en hombres. Conclusiones. Durante el período estudiado, la mortalidad por cáncer en Chile estuvo fuertemente asociada al NE de la población. Esta información debe ser considerada al definir estrategias nacionales para reducir la mortalidad específica por cáncer en los grupos más desprotegidos.

Conhecimento popular: impactos e métodos de controle de Achatina fulica em Valença – RJ, Brasil

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Evelyn Chicarino Durço

2012-12-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2013v26n1p189 O objetivo deste estudo foi verificar a incidência do caramujo africano Achatina fulica no bairro Cambota, Valença-RJ, Brasil, e investigar as estratégias de controle adotadas pela população. Questionários epidemiológicos aplicados a 105 moradores averiguaram a existência de contato deles com o animal, o risco de contágio por parasitos, por conta dos hábitos de higiene, e os métodos de controle adotados. A presença dos moluscos foi relatada em 52,5% das residências visitadas. Dessas, 51,4% apresentaram roedores. Moluscos coletados foram analisados quanto à presença de nematoides. Nas residências positivas para a presença de A. fulica foi relatado contato direto com os moluscos (21,9% por manuseio (muitas vezes inadequado ou por ingestão. Todos os entrevistados disseram utilizar alguma técnica para higienização dos alimentos e 67,6% relataram conhecer a angiostrongilíase. Todos os entrevistados disseram praticar o extermínio dos moluscos, 28,5% desses efetuando a quebra da concha. Apesar da alta incidência de A. fulica, não foram encontradas larvas de Angiostrongylus sp. ou de outros nematoides de importância médico-veterinária nos espécimes analisados.

Muerte materna por malaria grave por Plasmodium vivax

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Nancy Arróspide

Full Text Available Se presenta el caso de una mujer de 19 años con 29 semanas de gestación, procedente de Llumpe (Ancash con antecedentes de viajes a las localidades de Chanchamayo (Junín y Rinconada (Ancash. Ingresó al Hospital de Chacas (Ancash por presentar mal estado general, deshidratación, dificultad respiratoria, ictericia, sensación de alza térmica y dolor abdominal, tuvo reporte de: hemoparásitos 60% en frotis sanguíneo. Fue transferida al Hospital Ramos Guardia (Huaraz donde presentó mayor dificultad respiratoria, coluria, hematuria, disminución del débito urinario y reporte de Plasmodium (+, luego fue transferida al Hospital Cayetano Heredia (Lima donde ingresó a la Unidad de Cuidados Intensivos (UCI, con evolución a falla multiorgánica, óbito fetal y muerte materna. Se confirmó infección por Plasmodium vivax. Destacamos la importancia de mejorar nuestras capacidades de diagnóstico y manejo para brindar un tratamiento adecuado y oportuno.

Desenvolvimento de um kit de irrigação por microtubos com moto-bomba propulsionada por energia solar

OpenAIRE

Luiz Ricardo Sobenko

2016-01-01

O bombeamento de água por meio da energia solar vem se mostrando uma alternativa para localidades onde outras fontes de energia não estão disponíveis ou são limitadas. Torna-se interessante aliar essa alternativa a um sistema de irrigação que opera com vazão e pressão relativamente baixas, como a irrigação localizada por microtubos, possibilitando assim a obtenção de alta eficiência. No presente trabalho teve-se por objetivo dimensionar e avaliar um kit de irrigação por microtubos, alimentado...

Tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional, 2000-2010

OpenAIRE

Cristian A. Herrera Riquelme; Lucy Kuhn-Barrientos; Roberto Rosso Astorga; Jorge Jiménez de la Jara

2015-01-01

Objetivo. Caracterizar la tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional en el período 2000-2010 en la población mayor de 20 años. Métodos. Cálculo de las tasas de mortalidad específica por cáncer ajustadas por edad para diferentes niveles educacionales (NE), para el período 2000-2010. Las tasas obtenidas se analizaron con un modelo de regresión de Poisson, calculando el índice de desigualdad relativa (IDR) y el índice de desigualdad de la pendiente (ID...

Polución por material particulado fino (PM 2,5) incrementa las hospitalizaciones por insuficiencia cardiaca

OpenAIRE

Castro, Pablo; Vera, Jeanette; Cifuentes, Luis; Wellenius, Gregory; Verdejo, Hugo; Sepúlveda, Luis; Vukasovic, José Luis; Llevaneras, Silvana

2010-01-01

Antecedentes: Estudios recientes han reportado una asociación entre la contaminación ambiental por material particulado (PM) y el riesgo de hospitalizaciones de pacientes con insuficiencia cardiaca (IC). La región metropolitana de nuestro país constituye un área geográfica en la cual la contaminación es especialmente relevante, asociándose a incrementos periódicos en la morbimortalidad por causa respiratoria. Sin embargo el efecto de la polución por PM en la morbilidad de pacientes con IC no ...

Avaliação das intoxicações por domissanitários em uma cidade do Nordeste do Brasil Evaluación de las intoxicaciones por productos domésticos en una ciudad del Nordeste de Brasil Poisoning with household cleaning products in a city in Northeast Brazil

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Gerson Bragagnoli

2013-05-01

Full Text Available Este trabalho analisa as exposições tóxicas a domissanitários registradas pelo Centro de Informação e Assistência Toxicológica de Campina Grande, Paraíba, Brasil, no período de 2007 a 2010. Os dados foram coletados das fichas de notificação do Sistema de Informação de Agravos de Notificação (SINAN, analisados pelo software SPSS (Versão 17, e a identificação química em amostras de urina foi feita por técnicas cromatográficas de alta resolução (CG-MS e HPLC-UV. Foram registradas 660 intoxicações e, considerando as variáveis de estudo, observados como principais agentes causais os agrotóxicos (42,2%.Os intoxicados por saneantes domésticos na região são predominantemente crianças (30,1%, e/ou do gênero feminino (55,21%, que se expõem ao produto acidentalmente (55,4% pela via oral (82%. Diante desses dados, conclui-se que a intoxicação por domissanitários em Campina Grande e região deve ser tratada com ações específicas de prevenção e controle junto à população, como a avaliação da facilidade de acesso aos venenos agrícolas, para que se consiga atingir as metas estabelecidas pelo Plano Nacional de Saúde, para o quadriênio 2012-2015.Este trabajo analiza las exposiciones tóxicas a productos domésticos registradas por el Centro de Información y Asistencia Toxicológica de Campina Grande, Paraíba, Brasil, durante el periodo de 2007 hasta 2010. Los datos fueron recogidos mediante la información proporcionada por el Sistema de Notificación de Enfermedades (SINAN y analizados por el software SPSS (versión 17. La identificación química en muestras de orina fue realizada mediante alta resolución con técnicas de cromatografía (GC-MS y HPLC-UV. Se registraron 660 intoxicaciones y, teniendo en consideración las variables del estudio, se observó que los principales agentes causales eran los pesticidas (42,2% y que los envenenados por productos domésticos de limpieza en la región eran en su mayor

Fobia específica: um estudo transversal com 103 pacientes tratados em ambulatório

OpenAIRE

Terra,Mauro Barbosa; Garcez,Joana Presser; Noll,Betina

2007-01-01

OBJETIVOS: Este estudo tem por objetivo investigar a presença de fobia específica (FE) entre pacientes atendidos em um ambulatório de psiquiatria. MÉTODOS: Foi realizado um estudo transversal, no qual foi aplicado o SCID-I em 103 pacientes, para se examinar a ocorrência de fobia específica. Os dados foram analisados por meio de medidas descritivas e mediante os testes de independência baseados na estatística qui-quadrado de Pearson ou no teste exato de Fisher. RESULTADOS: Foi verificada FE em...

Guilty victims: a model to perpetuate impunity for work-related accidents

OpenAIRE

Vilela, Rodolfo Andrade Gouveia; Iguti, Aparecida Mari; Almeida, Ildeberto Muniz

2004-01-01

Neste artigo analisam-se os laudos e dados obtidos das investigações de acidentes graves e fatais do trabalho efetuadas pelo Instituto de Criminalística (IC), Regional de Piracicaba. Foram analisados 71 laudos de acidentes ocorridos em 1998, 1999 e 2000. Os acidentes envolvendo máquinas representam 38,0%, seguido pelas quedas de altura (15,5%) e em terceiro lugar os causados por corrente elétrica (11,3%). Os laudos concluem que 80,0% dos acidentes são causados por "atos inseguros" cometidos p...

Distrofia miotônica: análise clínico-genética de uma família

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Jeová Barros da Silva

1970-03-01

Full Text Available Mediante o estudo de um caso probando foi possível fazer levantamento genealógico de uma família com 12 membros de ambos os sexos, afetados por distrofia miotônica. São analisados aspectos clínicos e laboratoriais, muitos dos quais confirmam trabalhos publicados anteriormente. Algumas novas contribuições são feitas uma vez que alguns dados são discrepantes dos já anteriormente registrados. A hereditariedade desta anomalia caracteriza-se por transmissão de um fator dominante e autossômico.

Salvia officinalis (Lamiaceae) Lin. : caracterização química, atividade citotóxica e apoptótica em células de mamíferos

OpenAIRE

Garcia, Charlene Silvestrin Celi

2014-01-01

Salvia officinalis (Lamiaceae), conhecida popularmente como sálvia, tem sido muito utilizada no sul do Brasil como condimento nos alimentos, tintura hidroalcoólica e chá para o tratamento de vários distúrbios de saúde. As propriedades dessa planta são estudadas por apontar possíveis mecanismos de ação antioxidante e antitumoral. Neste trabalho, o extrato hidroalcoólico e aquoso de sálvia foram analisados quimicamente por meio de cromatografia gasosa acoplada a espectrômetro de massas (GC-MS) ...

Os óleos essenciais das folhas e galhos finos de Aniba canelilla (Kunth) Mez coletados em Manaus, B

OpenAIRE

Lima, Maria da Paz; Silva, Tatiana Maria D.; Silva, João Domingos da; Zoghbi, Maria das Graças B.; Andrade, Eloisa Helena A.

2004-01-01

The essential oil of the leaves and fine stems of Aniba canelilla (Kunth) Mez collected in the city of Manaus, AM, Brazil, were obtained by hydrodistillation and analyzed by GC/MS. Forty-two components were identified, of which 1-nitro-2-phenylethane, as expected, was the major (71.2%-68.2%).Os óleos essenciais das folhas e dos galhos finos de Aniba canelilla (Kunth) Mez coletada na cidade de Manaus, AM, Brasil, foram obtidos por hidrodestilação e analisados por CG-EM. Quarenta e dois compone...

Caracterização acústica de vogais orais na fala infantil: o falar florianopolitano = Acoustic characterization of oral vowels on children speech: the dialect from Florianopolis

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Brod, Lilian Elisa Minikel

2014-01-01

Full Text Available Este artigo teve como objetivo apresentar uma descrição acústica de vogais orais tônicas do português brasileiro produzidas por crianças florianopolitanas de 10 e 11 anos de idade, a partir dos parâmetros de duração relativa e primeiro e segundo formantes. Para evitar os efeitos das diferenças fisiológicas entre crianças do sexo masculino e feminino, os dados foram normalizados a partir do método Lobanov. Duas análises foram realizadas. Primeiro, os dados normalizados das sete vogais orais foram analisados em função do gênero e os resultados mostraram diferenças significativas para a vogal baixa, sendo mais centralizada para crianças do sexo masculino. Segundo, os dados normalizados das vogais [e, a, o] foram analisados em função da tonicidade e ponto de articulação. Foram observadas diferenças significativas em relação à tonicidade e ponto de articulação para ambos os grupos analisados

Quantitative analysis of Ni2+/Ni3+ in Li[NixMnyCoz]O2 cathode materials: Non-linear least-squares fitting of XPS spectra

Science.gov (United States)

Fu, Zewei; Hu, Juntao; Hu, Wenlong; Yang, Shiyu; Luo, Yunfeng

2018-05-01

Quantitative analysis of Ni2+/Ni3+ using X-ray photoelectron spectroscopy (XPS) is important for evaluating the crystal structure and electrochemical performance of Lithium-nickel-cobalt-manganese oxide (Li[NixMnyCoz]O2, NMC). However, quantitative analysis based on Gaussian/Lorentzian (G/L) peak fitting suffers from the challenges of reproducibility and effectiveness. In this study, the Ni2+ and Ni3+ standard samples and a series of NMC samples with different Ni doping levels were synthesized. The Ni2+/Ni3+ ratios in NMC were quantitatively analyzed by non-linear least-squares fitting (NLLSF). Two Ni 2p overall spectra of synthesized Li [Ni0.33Mn0.33Co0.33]O2(NMC111) and bulk LiNiO2 were used as the Ni2+ and Ni3+ reference standards. Compared to G/L peak fitting, the fitting parameters required no adjustment, meaning that the spectral fitting process was free from operator dependence and the reproducibility was improved. Comparison of residual standard deviation (STD) showed that the fitting quality of NLLSF was superior to that of G/L peaks fitting. Overall, these findings confirmed the reproducibility and effectiveness of the NLLSF method in XPS quantitative analysis of Ni2+/Ni3+ ratio in Li[NixMnyCoz]O2 cathode materials.

XPS and SIMS characterisation of TiOxNy solar absorber films

International Nuclear Information System (INIS)

Metson, J.B.; Prince, K.E.; Bittar, A.; Tornquist, J.

1999-01-01

Full text: TiO x N y thin films have useful properties as selective solar absorbers when used in tandem with a collector substrate. Such films are transparent across a reasonable window of the solar spectrum, but have low thermal emissivity. They are however limited by their thermal stability under the typical operating conditions they experience. In this study, TiO x N y films have been deposited on Si and Cu substrates using ion beam assisted deposition. The films are amorphous and x and y were controlled by altering the O 2 /N 2 ratio in the gas source. After annealing at temperatures of 200 - 400 deg C, films have been depth profiled using Secondary Ion Mass Spectrometry. Profiles reveal the degradation of the film by migration of the substrate atoms through the films, to the sample surface. In general, films with x 1 show improved stability, ultimately at the expense of a reduced transmission window. Thermal stability is also improved by the use of diffusion barriers either at the substrate film interface or at the surface of the film. However contrary to previous suggestions, the degradation mechanism involves the formation not of an oxide at the film surface but a phase which is nitrogen rich. The nature of this phase, formed by diffusion of the substrate atoms, has been investigated by X-ray photoelectron spectroscopy (XPS). These investigations reveal very complex behaviour in the early stages of film failure, with an almost intact TiO x N y layer surviving, but being progressively buried by the growth of the reaction layer at the film surface. Copyright (1999) Australian X-ray Analytical Association Inc

Síndrome de Munchausen por mandato

OpenAIRE

Esteban, Miguel A.; Pérez, Miriam R.; Bracco, Anahí

2006-01-01

El Síndrome de Munchausen por mandato, "un trastorno ficticio, por el cual la enfermedad del niño es inducida, promovida o provocada por la persona más próxima a él, generalmente su madre", es todavía mal conocido y su génesis imperfectamente comprendida. Esta comunicación está destinada a esclarecer al pediatra esta patología, con elevada morbilidad y secuelas, como así también de altísima mo...

Análise desagregada da inflação por setores industriais da economia brasileira entre 1996 e 2011

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Carlos Pinkusfeld Monteiro Bastos

2015-08-01

Full Text Available RESUMO Este artigo reporta uma investigação empírica sobre a dinâmica inflacionária de dezessete setores industriais da economia brasileira entre 1996 e 2011. A partir de uma breve discussão teórica sobre a relação entre a inflação e a demanda agregada nas abordagens convencional (modelo do Novo Consenso, pós-keynesiana e do conflito distributivo, buscaram-se evidências de inflação de excesso de demanda e de pressões de custo nesses setores. As séries temporais utilizadas foram o Índice de Preço ao Produtor Amplo por Origem (IPA-OG, o grau de Utilização da Capacidade Instalada (ambos da FGV, o Índice deCommodities Internacionais (IFS/FMI, a taxa de juros e a taxa de câmbio nominal (ambas do Banco Central do Brasil − BCB. As equações foram estimadas a partir da Metolodogia ADL (Autoregressive Distributed Lags . Os resultados apontaram para a ausência de uma relação forte e sistemática entre a inflação e a demanda agregada e para evidência de pressões de custo, sobretudo os preços internacionais das commodities e o câmbio, como determinantes da dinâmica inflacionária dos setores e período analisados.

PTA hardfacing of Nb/Al coatings Revestimentos Nb/Al depositados por PTA

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Karin Graf

2012-06-01

caracterizados revestimentos utilizando uma liga fundida e triturada de Nb40wt%Al e analisado o efeito do Fe e do C nas características dos revestimentos. O trabalho confirmou que é possível processar revestimentos íntegros de Nb40wt%Al por PTA e que ocorre uma forte interação com o substrato, que vai determinar a microestrutura final e as propriedades do revestimento. Destaca-se que na customização de revestimentos de Nb-Al a diluição tem de ser considerada logo nos estágios iniciais do projeto do revestimento.

Morphology and chemical characteristics of micro- and Nano-particles in the haze in Beijing studied by XPS and TEM/EDX

Energy Technology Data Exchange (ETDEWEB)

Xu, Peng [Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, and Laboratory of Catalysis Chemistry and Nanoscience, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing, 100190 (China); Xu, Jianxun; He, Meng [CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing, 100190 (China); Song, Lexin [Department of Chemistry, University of Science and Technology of China, Hefei, 230026 (China); Chen, Dongliang, E-mail: chendl@mail.buct.edu.cn [College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Guo, Guangsheng, E-mail: guogs@bjut.edu.cn [Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, and Laboratory of Catalysis Chemistry and Nanoscience, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Dai, Hongxing, E-mail: hxdai@bjut.edu.cn [Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, and Laboratory of Catalysis Chemistry and Nanoscience, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China)

2016-09-15

X-ray Photoelectron Spectroscopy (XPS) is a useful surface sensitive tool to explore the particulate matter with different particle sizes. In this work, we report the analysis of elemental species in particulate matter with size ranging from 100 nm to 10 μm during the autumn haze of 2014 in Beijing. The size dependence of element composition and chemical state distribution on the particle surface was investigated. It was found that the number of investigated element species decreased from 8 (at stage 2) to 4 (at stage 10) with the decrease of particle sizes down to 100 nm, which is in accordance with the result from Transmission electron microscopy (TEM/EDX) observations. Three chemical states of nitrogen, the amide group (399.9 eV), the ammonium group (401.6 eV), and the nitrate group (407.2 eV), were confirmed according to the different binding energies. Nitrate was the main composition on the coarse particles, while the percentage of amide and ammonium at stage 3 (13.9% and 10.8% respectively) increased on the fine particles at stage 9 (46.8% and 38.8% respectively). The relative ratio of sulfate and ammonium (calculated 1:1) in the fine particles suggests that there is no enough NH{sub 4}{sup +} to neutralize the sulfuric acid and the surface of the PM is acidic. The result is useful to investigate the generation processes and the sources of collected particles. - Highlights: • The element composition of particles from 100 nm to 10 μm in haze was discussed • The chemical state was dominated by the particle size • The surface of PM was acidity • XPS was shown a useful tool in the aerosol research.

DESGASTE POR ABRASIÓN DEL ACERO API 5L X65 REVESTIDO CON NIOBIO POR ASPERSIÓN TÉRMICA A PLASMA Y CON INCONEL 625 POR SOLDADURA

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JOSE MATOS

2012-01-01

Full Text Available El objetivo de este trabajo fue evaluar y caracterizar el comportamiento mecánico en desgaste del acero API 5L X65, revestido con niobio en comparación al desempeño del revestimiento de la aleación de inconel 625 empleados en la industria de petróleo y gas. El revestimiento de niobio fue obtenido por el proceso de aspersión térmica a plasma de arco no transferido y el revestimiento inconel 625 por soldadura con electrodo revestido. La resistencia al desgaste por abrasión fue evaluada según la norma Petrobras N-2568, en un tribómetro CTER, la rugosidad y el volumen de material desgastado se determinó a través de perfilometría y la dureza de los revestimientos por microscopia Vickers. Los revestimientos obtenidos fueron caracterizados respecto a su morfología por microscopia electrónica de barrido (MEB y microscopía óptica (MO. La mayor dureza del revestimiento con niobio obtenido puede haber contribuido a reducir la tasa de desgaste en comparación con el revestimiento de inconel 625.

Nurses' attitudinal and normative beliefs concerning hemodynamic assessement by pulmonary artery catheterization Creencias normativas y de actitud de los enfermeros sobre el estudio hemodinámico por medio del catéter de arteria pulmonar Crenças atitudinais e normativas dos enfermeiros sobre o estudo hemodinâmico por meio do cateter de artéria pulmonar

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Cristiano José Mendes Pinto

2006-12-01

artéria pulmonar (CAP. A coleta de dados foi realizada por meio de entrevista semi-estruturada junto a 23 enfermeiros de unidades de terapia intensiva de três hospitais do município de Campinas, SP. Os dados foram analisados segundo metodologia qualitativa. Dentre as crenças de atitude destacaram-se as crenças afetivas e aquelas relativas às vantagens e desvantagens da realização do comportamento. Nas crenças normativas foram evidenciados os referentes sociais para a execução do comportamento, bem como fatores estimuladores e desestimuladores da realização do EH.

Nursing Intervention Classifications (NIC validated for patients at risk of pressure ulcers Intervenciones de la Clasificación de Enfermería NIC validadas para pacientes en riesgo de úlcera por presión Intervenções da Classificação de Enfermagem NIC validadas para pacientes em risco de úlcera por pressão

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Taline Bavaresco

2012-12-01

Full Text Available OBJECTIVE: to validate the Nursing Intervention Classifications (NIC for the diagnosis 'Risk of Impaired Skin Integrity' in patients at risk of pressure ulcers (PU. METHOD: the sample comprised 16 expert nurses. The data was collected with an instrument about the interventions and their definitions were scored on a Likert scale by the experts. The data was analyzed statistically, using the calculation of weighted averages (WA. The study was approved by the Research Ethics Committee (56/2010. RESULTS: nine interventions were validated as 'priority' (WA ≥0.80, among them Prevention of PU (MP=0.92; 22 as 'suggested' (WA >0.50 and OBJETIVO: validar las intervenciones de la clasificación de enfermería NIC para el diagnóstico Riesgo de Integridad de la Piel Perjudicada en pacientes en riesgo de úlcera por presión (UP. MÉTODO: la muestra fue compuesta por 16 enfermeras experts. Los datos colectados en instrumento con las intervenciones, su definición y una escala Likert puntuada por las experts. Los datos analizados estadísticamente, utilizándose cálculo de media ponderada (MP. Estudio aprobado en Comité de Ética e Investigación (56/2010. RESULTADOS: se validaron nueve intervenciones como prioritarias (MP ≥0,80, entre ellas Prevención de UP (MP=0,92; 22 como sugeridas (MP >0,50 OBJETIVO: validar as intervenções da classificação de enfermagem NIC para o diagnóstico Risco de Integridade da Pele Prejudicada, em pacientes em risco de úlcera por pressão (UP. MÉTODO: a amostra foi composta por 16 enfermeiras experts. Os dados foram coletados em instrumento contendo a caracterização das participantes, além de uma tabela com as intervenções e a definição de cada uma delas, bem como uma escala Likert que foi pontuada pelas experts. Os dados foram analisados estatisticamente, utilizando-se cálculo de média ponderada (MP. O estudo foi aprovado em Comitê de Ética e Pesquisa (56/2010. RESULTADOS: validaram-se nove interven

CARACTERÍSTICAS DA VIOLÊNCIA SEXUAL SOFRIDA POR CRIANÇAS ASSISTIDAS POR UM PROGRAMA DE APOIO

OpenAIRE

KELLY LINHARES VASCONCELOS; ADRIANA GOMES NOGUEIRA FERREIRA; ELIANY NAZARÉ OLIVEIRA; DANIELLE D\\u2019ÁVILA SIQUEIRA; PATRÍCIA NEYVA DA COSTA PINHEIRO

2010-01-01

En Brasil, las estadísticas de la violencia sexual contra niños están lejos de reflejar la verdadera realidad actual debido a la baja notificación de los casos. La finalidad de este estudio fue caracterizar el abuso sexual sufrido por niños asistidos por el Programa Sentinela y el perfil del agresor, en Sobral-Ceará, en el periodo que va del 2002 al 2006. La muestra no probabilística intencional fue compuesta por 50 víctimas de abuso sexual y de las mismas, el 66% es del sexo femenino, con pr...

Análise das variações climáticas na ocorrência de doenças respiratórias por influenza em idosos na região metropolitana de João Pessoa – PB / Analysis of climatic variations in the occurrence of Respiratory diseases by influenza in elderly people in the metropolitan region of João Pessoa – PB

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Jullianna Vitorio Vieira de Azevedo

2017-05-01

Full Text Available Neste trabalho objetivou-se avaliar os efeitos das variações sazonais do clima na ocorrência de internações por doenças respiratórias por Influenza e Pneumonia (PI na população idosa da Região Metropolitana de João Pessoa (RMJP no Estado da Paraíba. Para isso, foram usados modelos lineares generalizados a partir da regressão linear de Poisson para relacionar a variável dependente configurada como os registros de internações por causas associadas à influenza e as variáveis independentes (precipitação pluvial, temperatura média do ar e umidade relativa do ar, para análise das relações instituídas pela modelagem foi aplicado o teste de variância ANOVA com nível de significância de 0,05 de probabilidade para determinar que variáveis independentes eram mais significativas na modelagem. Também foram analisados os resíduos gerados pelo ajuste dos modelos no intuito de identificar a distribuição que melhor se ajustasse aos dados. Toda análise estática foi realizada no software R. De forma geral verificou-se que os maiores picos de internações por PI ocorrem no outono e inverno. Portanto, esses resultados sugerem uma associação entre o frio e as internações por PI. A modelagem estatística se apresentou satisfatória para análise dos casos de internações por PI, no entanto, é necessário o aprofundamento dessas análises temporais, visto que o problema de internações é multicausal e não, necessariamente, consequência somente de alterações climáticas.

Abdome agudo por obstrução por ileobiliar

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Márcia Cristina de Alencastro

Full Text Available OBJETIVO: descrever a experiência na abordagem dos doentes com abdome agudo por obstrução por IB, desde o diagnóstico até o tratamento definitivo. MÉTODOS: estudo retrospectivo incluindo todos os casos de IB tratados em um período de 23 anos. De acordo com a abordagem cirúrgica realizada, os pacientes foram divididos em dois grupos (1 enterolitotomia com colecistectomia no segundo momento; e (2 enterolitotomia, colecistectomia e abordagem da fístula. RESULTADOS: Doze pacientes foram incluídos, sendo 11 mulheres (91,6%, com média de idade de 72,2 anos. Todos os pacientes apresentavam doenças associadas, principalmente hipertensão arterial sistêmica (75%. Dois pacientes não apresentavam sintomas significativos de obstrução intestinal. O diagnóstico de IB foi realizado em seis pacientes (50% antes da laparotomia. O grupo 1 foi constituído de oito pacientes e o grupo 2 de quatro, e a morbidade foi, respectivamente, 33,3% e 8,3%. A mortalidade foi 16,6% (um paciente de cada grupo. CONCLUSÃO: O manejo do IB deve ser individualizado. O tratamento da obstrução mediante remoção do cálculo biliar por enterotomia proximal é a escolha inicial para o tratamento do IB. A colecistectomia e a correção da fístula bilioentérica podem ser realizadas juntamente com a remoção do cálculo, no entanto, em pacientes com comorbidades significativas, esses procedimentos devem ser realizados posteriormente.

An in situ XPS study of growth of ITO on amorphous hydrogenated Si: Initial stages of heterojunction formation upon processing of ITO/a-Si:H based solar cell structures

Energy Technology Data Exchange (ETDEWEB)

Diplas, Spyros; Thoegersen, Annett; Ulyashin, Alexander [SINTEF Materials and Chemistry, Oslo (Norway); Romanyuk, Andriy [University of Basel, Basel (Switzerland)

2015-01-01

In this work we studied the interface growth upon deposition of indium-tin oxide (ITO) on amorphous hydrogenated Si (a-Si:H)/crystalline Si (c-Si) structures. The analysis methods used were X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) in combination with in situ film growth with magnetron sputtering. The analysis was complemented with transmission electron microscopy (TEM) of the deposited films. The sputtering equipment was attached to the XPS spectrometer and hence early stage film growth was observed without breaking the vacuum. It was shown that during early deposition stages ITO is reduced by a-Si:H. The reduction is accompanied with formation of metallic In and Sn at the interface. Formation of Sn is more enhanced on a-Si substrates whilst formation of In is more dominant on c-Si substrates. The reduction effect is less intense for amorphous hydrogenated Si as compared to crystalline Si and this is attributed to stronger presence of dangling bonds in the latter than the former. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Uso das diretrizes para tratamento da úlcera por pressão por enfermeiros de um hospital geral

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Elaine Maria Leite Rangel

2009-03-01

Full Text Available Este estudo objetivou identificar a freqüência do uso das diretrizes para o tratamento da úlcera por pressão(UP por enfermeiros de um hospital geral no interior do estado de São Paulo. É transversal de caráterdescritivo com análise quantitativa de dados. Amostra de 25 enfermeiros. Para a coleta de dados utilizou-se uminstrumento, construído a partir das diretrizes para o tratamento da UP. As questões foram relacionadas aostipos de intervenções usadas pelos enfermeiros para o tratamento da UP em estágio I, II, com necrose e comtecido de granulação. Para UP em estágio I, 24 (96% enfermeiros sempre realizavam a mudança de decúbito.Nas úlceras em estágio II a utilização de óleos vegetais na ferida era realizada sempre por 10 (40%enfermeiros e o curativo de hidrocolóide nunca era utilizado por 12 (57,1% enfermeiros. Em UP com necrose alimpeza com povidine era realizada por 4 (17,4% enfermeiros às vezes. Para o desbridamento, 16 (64% àsvezes utilizavam papaína e 15 (71,4% às vezes utilizavam colagenase. Em úlceras com tecido de granulaçãosempre era utilizado o soro fisiológico por 25 (100% enfermeiros. Houve variação nas práticas para otratamento da UP e falta de adesão às diretrizes.

Mortalidad por causas externas en Medellín, 1999-2006

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Doris Cardona Arango

2008-01-01

Full Text Available Caracterizar el comportamiento de la mortalidad por causas externas en la ciudad de Medellín, Colombia, entre 1999-2006, según sexo, edad y causa básica de muerte fue el objetivo de este estudio descriptivo longitudinal, con fuente de información secundaria de 22 128 registros de defunción por causas externas. El análisis realizado es univariado y bivariado por sexo, grupos de edad y causa de muerte. Las causas externas registradas en el periodo fueron: 72.9 por ciento por homicidio; 15.3 por ciento, accidente de transporte; 7.3 por ciento, traumatismos; 4.2 por ciento, por suicidio, y por otras causas, 0.4 por ciento. La mayor tasa de mortalidad se presentó en el grupo de edad de 20 a 24 años (27.6 por cien mil habitantes, hecho que merece especial consideración por las implicaciones sociales, familiares y laborales que representa el fallecimiento de una persona en su etapa productiva.

Hanseníase: estigma e preconceito vivenciados por pacientes institucionalizados em Santa Catarina (1940-1960 Lepra: estigma y prejuicio vivido por pacientes institucionalizados en Santa Catarina, Brasil (1940-1960 Leprosy: stigma and prejudice lived by institucionalized patients in Santa Catarina State, Brazil (1940-1960

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Miriam Süssking Borenstein

2008-11-01

Full Text Available Trata-se de uma pesquisa qualitativa com abordagem sócio-histórica cujo objetivo foi conhecer o estigma e preconceito vivenciado por pacientes/residentes institucionalizados acometidos pela hanseníase. Para tanto, foram entrevistados três pacientes que viveram em um hospital colônia no período do estudo, utilizando-se o método de história oral. Os dados foram coletados e posteriormente analisados, utilizando-se do referencial de estigma. Os resultados evidenciaram que após o ingresso na instituição, esses doentes tiveram seus laços familiares rompidos, perderam seus direitos como cidadãos, em decorrência dessa situação, assumiram novas vidas em um novo contexto. Concluindo, o isolamento nosocomial por um longo período de tempo (anos de internação e afastamento, provocou a morte simbólica de muitos pacientes que viviam com a esperança de um retorno ao convívio familiar e/ou social.El presente es un estudio de investigación cualitativa con abordaje socio-histórica. Tuvo como objetivo conocer el estigma y el prejuicio vivido por los pacientes institucionalizados portadores de lepra. Utilizándose el método de história oral, fueran entrevistados tres pacientes, que vivieron en un hospital en el período del estudio. Los datos fueran colectados y después analizados utilizándose el referencial del estigma. Los resultados colocaran en evidencia que, después del ingreso en la instituición, las personas tuvieran sus lazos familiares rotos, perdieran sus derechos como ciudadanos y asumiran nuevas vidas en un nuevo contexto. En conclusión, el aislamiento nosocomial por uno largo período de tiempo (años de internación y aislamiento, provocó la muerte simbólica de muchos que vivian con la esperanza del regreso a la convívencia familial y social.This study is a qualitative research with a socio-historic approach whose objective was to know the prejudice and stigma lived by the institutionalized patients/residents with

Aproveitamento teórico-prático da disciplina anatomia humana do curso de fisioterapia

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Rodrigo Moreira Arruda

Full Text Available A Anatomia Humana estuda as estruturas do corpo humano e as relações entre elas. Assim, seu ensino a estudantes da área da saúde, incluindo alunos de Fisioterapia, é de extrema importância. É necessário um bom aproveitamento nesta disciplina para se tornar um bom profissional, porém as estratégias de ensino-aprendizagem nesta disciplina têm sido bastante discutidas. Com base nesta premissa, este estudo teve por objetivos avaliar o aproveitamento teórico-prático dos discentes do curso de Fisioterapia na disciplina Anatomia Humana, bem como descrever as facilidades e dificuldades enfrentadas e suas implicações durante o curso. Para tanto, foi elaborado um questionário específico e utilizada também a avaliação dos professores realizada pelo Colegiado de Fisioterapia. O tratamento estatístico foi composto por análise descritiva e correlação de Pearson, sendo os dados analisados pelos programas Microsoft Excel® 2007 e Graphpad Prism®. Não se observou correlação entre desempenho do aluno e grau de satisfação diante de diferentes parâmetros analisados neste trabalho. O estudo revelou que os alunos apresentam aproveitamento satisfatório, mas há grandes insatisfações quanto à forma como a disciplina é conduzida.

Comprometimento organizacional: um estudo no Tribunal de Justiça do Estado de Minas Gerais

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Renata Dias Botelho

2011-10-01

Full Text Available O objetivo deste estudo foi descrever e analisar como se encontra configurado o comprometimento organizacional dos servidores do Fórum Lafayette, Belo Horizonte (MG, em face das dificuldades enfrentadas pela organização diante da substituição e diminuição do quadro funcional, fruto do cumprimento de dispositivos legais. O modelo analítico adotado foi a abordagem multidimensional de Meyer e Allen (1991. A pesquisa empírica se caracteriza como de campo, descritiva, com abordagens quantitativa e qualitativa. Como técnicas de coleta de dados foram utilizados: levantamento documental (dados secundários que foram analisados por meio de análise documental, questionários (dados primários tabulados estatisticamente, de forma uni e bivariada e entrevistas (dados primários analisados por meio das técnicas de análise de conteúdo, caracterizando uma triangulação entremétodos. Observaram-se fragilidades no que tange ao comprometimento dos servidores abordados, os quais se pautam substancialmente em sua estabilidade, e correlações entre dados demográficos e dimensões normativa e calculativa do comprometimento em vários sentidos, além de contradições entre dados obtidos por meio de diferentes instrumentos. Diante das limitações do estudo, diversas sugestões para pesquisas futuras foram listadas.

Rearranjo estrutural de PET durante compressão plana

OpenAIRE

Elton Luis Gasparotto Denardin

2004-01-01

As características da tensão – deformação do Poli(tereftalato de etileno) (PET) durante o processo de deformação por compressão plana tem sido estudadas. Amostras de PET com e sem tratamento térmico obtidas por injeção foram deformadas a diferentes temperaturas de deformação, abaixo e acima da temperatura de transição vítrea (Tg) utilizando diferentes taxas de deformação e tensões finais aplicadas. O comportamento mecânico foi analisado através das curvas de tensão – deformação obtidas por de...

Apendicitis por Paracoccidioides brasiliensis

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Ana Beatriz MUÑOZ URRIBARRI

2006-01-01

Full Text Available La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis por esta patología. (Rev Med Hered 2006;17:58-60.

Raman and XPS characterization of vanadium oxide thin films with temperature

Energy Technology Data Exchange (ETDEWEB)

Ureña-Begara, Ferran, E-mail: ferran.urena@uclouvain.be [Université catholique de Louvain, Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Louvain-la-Neuve (Belgium); Crunteanu, Aurelian [XLIM Research Institute, UMR 7252, CNRS/Université de Limoges, Limoges (France); Raskin, Jean-Pierre [Université catholique de Louvain, Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Louvain-la-Neuve (Belgium)

2017-05-01

Highlights: • Comprehensive study of the oxidation of VO{sub 2} thin films from R.T. up to 550 °C. • Phase changes and mixed-valence vanadium oxides formed during the oxidation process. • Reported Raman and XPS signatures for each vanadium oxide. • Monitoring of the current and resistance evolution at the surface of the films. • Oxidation model describing the evolution of the vanadium oxides and phase changes. - Abstract: The oxidation mechanisms and the numerous phase transitions undergone by VO{sub 2} thin films deposited on SiO{sub 2}/Si and Al{sub 2}O{sub 3} substrates when heated from room temperature (R.T.) up to 550 °C in air are investigated by Raman and X-ray photoelectron spectroscopy. The results show that the films undergo several intermediate phase transitions between the initial VO{sub 2} monoclinic phase at R.T. and the final V{sub 2}O{sub 5} phase at 550 °C. The information about these intermediate phase transitions is scarce and their identification is important since they are often found during the synthesis of vanadium dioxide films. Significant changes in the film conductivity have also been observed to occur associated to the phase transitions. In this work, current and resistance measurements performed on the surface of the films are implemented in parallel with the Raman measurements to correlate the different phases with the conductivity of the films. A model to explain the oxidation mechanisms and phenomena occurring during the oxidation of the films is proposed. Peak frequencies, full-width half-maxima, binding energies and oxidation states from the Raman and X-ray photoelectron spectroscopy experiments are reported and analyzed for all the phases encountered in VO{sub 2} films prepared on SiO{sub 2}/Si and Al{sub 2}O{sub 3} substrates.

Measurements of Chlorine by XPS and SIMS in Nuclear-Grade Graphite. Effect of Treatment by UV, Heat and Moisture

International Nuclear Information System (INIS)

Grossiord, C.; Amalric, J.; Rahmani, L.

2016-01-01

Pieces of historical nuclear-grade graphite from the same block were submitted to a treatment involving soft or hard UV and heating in moist air. XPS investigations before treatment have shown that – at the geometric surface at least – chlorine binds more commonly by covalent (30 to 100% depending on spots) than ionic bonds. After treatment, bond types are more balanced, though hardly more uniform. Shifts of the ionic peak indicating an oxidised bond were not found. Surface chlorine was measured up to 0.04% atomic. Treatment by hard UV and heating in moist air for 1 ½ hours up to 122°C led to a decrease of surface chlorine by a factor of 2 as measured by ToF and XPS, helped by an etching technique that ensured the accurate positioning of the spots under analysis. Treatment for 8 hours up to 151°C resulted in a decrease of the ToF Cl/ 13 C signal for surface chlorine from 0.73 to 0.20 and of the atomic fraction from 0.02% to 0% as measured by XPS. SIMS investigations reveal that in the first 6 μm from the geometric surface, chlorine, hydrogen and oxygen have a decreasing profile suggestive of diffusion from the surface. In the vicinity to the surface the amounts of all three elements are much greater than in the bulk, possibly due to the availability of dangling bonds. It is speculated that when these are not saturated, back diffusion from the bulk under treatment may increase the quantity of surface chlorine. Treatment in moist air by hard UV for to 1 ½ hours has no marked effect on chlorine in the bulk, although it alters the quantities of hydrogen and oxygen. Treatment for 8 hours decreases chlorine by a factor of about 5 throughout the analysed depth of 6 μm and possibly farther to 15 μm, suggesting its diffusivity to be at least an order greater than 3.10 -16m 2 /s and possibly than 2.10 -15 m²/s, although a range of values is expected owing to the diverse tortuosity and constrictivity of pores. Ratios of hydrogen to oxygen and of chlorine to

The Activation of Non-evaporable Getters Monitored by AES, XPS, SSIMS and Secondary Electron Yield Measurements

CERN Document Server

Scheuerlein, C

2002-01-01

In this thesis the potential of the three classical surface analysis techniques Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and static secondary ion mass spectrometry (SSIMS) for the characterisation of non-evaporable getter (NEG) materials is assessed and artefacts are described. The various NEG samples have been analysed in the context of the development of NEG thin film coatings for use in accelerator ultra high vacuum (UHV) systems. The secondary electron yield (SEY), which is a functional surface property of great importance for the application of NEG to accelerators, has been measured. The maximum SEY of an air exposed TiZr and TiZrV coating can be reduced from above 2.0 to below 1.1 during a 2 h heat treatment at 250 and 200 °C, respectively. Saturating an activated TiZrV surface in UHV increases the maximum SEY by about 0.1. Thus, in UHV the SEY of an activated NEG coating does not exceed the threshold value of 1.35, above which multipacting is predicted to occur in th...

Histórias de perdas fetais contadas por mulheres: estudo de análise qualitativa

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Alba Lúcia Dias dos Santos

2004-04-01

Full Text Available OBJETIVO: (Reconhecer o significado da perda fetal para mulheres que vivenciaram a experiência, a partir da compreensão do processo de gravidez, com base em seus relatos. MÉTODOS: Pesquisa de análise qualitativa com base nas histórias de sete mulheres que vivenciaram a experiência de perda fetal, no município de Arujá, SP, no período de julho de 1998 a junho de 1999. As mulheres foram identificadas a partir de atestados de óbito de nascidos mortos no período de estudo, obtidos no Cartório de Registro Civil de Arujá. Como procedimentos metodológicos, foram utilizadas a técnica de história oral para a coleta de dados e a técnica de análise de conteúdo do material coletado. As entrevistas realizadas foram gravadas e transcritas integralmente, e posteriormente recortadas para análise. RESULTADOS: Os achados foram analisados, contemplando dois momentos: o contexto circunstancial da gravidez e o impacto após a perda, adotando-se categorias temáticas específicas. A primeira parte aborda a percepção da gravidez, a notícia da vinda do bebê, os problemas de saúde até a perda e o atendimento do serviço de saúde. O significado da perda do bebê para as mulheres desse estudo foi evidenciado por três eixos centrais: perda de parte dela, fatalidade atribuída ao divino e mudanças de atitude perante a vida. A rede social de apoio a essas mulheres foi constituída sobre dois pilares: a família e a igreja, sendo praticamente inexistente o apoio de serviços de saúde. Ao final, todas elas expressaram a vontade de viver, a necessidade de trabalhar, de estudar e, até mesmo, de ter nova gravidez. CONCLUSÕES: Faz-se necessária uma mudança de paradigma nessa missão de atender pessoas; é preciso humanizar o atendimento nos serviços de saúde. Ficou muito evidente a necessidade do acompanhamento de usuárias de serviços de saúde que tiveram uma perda fetal, por uma equipe multiprofissional. Foi evidenciada, também, a import

Histórias de perdas fetais contadas por mulheres: estudo de análise qualitativa

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Santos Alba Lúcia Dias dos

2004-01-01

Full Text Available OBJETIVO: (Reconhecer o significado da perda fetal para mulheres que vivenciaram a experiência, a partir da compreensão do processo de gravidez, com base em seus relatos. MÉTODOS: Pesquisa de análise qualitativa com base nas histórias de sete mulheres que vivenciaram a experiência de perda fetal, no município de Arujá, SP, no período de julho de 1998 a junho de 1999. As mulheres foram identificadas a partir de atestados de óbito de nascidos mortos no período de estudo, obtidos no Cartório de Registro Civil de Arujá. Como procedimentos metodológicos, foram utilizadas a técnica de história oral para a coleta de dados e a técnica de análise de conteúdo do material coletado. As entrevistas realizadas foram gravadas e transcritas integralmente, e posteriormente recortadas para análise. RESULTADOS: Os achados foram analisados, contemplando dois momentos: o contexto circunstancial da gravidez e o impacto após a perda, adotando-se categorias temáticas específicas. A primeira parte aborda a percepção da gravidez, a notícia da vinda do bebê, os problemas de saúde até a perda e o atendimento do serviço de saúde. O significado da perda do bebê para as mulheres desse estudo foi evidenciado por três eixos centrais: perda de parte dela, fatalidade atribuída ao divino e mudanças de atitude perante a vida. A rede social de apoio a essas mulheres foi constituída sobre dois pilares: a família e a igreja, sendo praticamente inexistente o apoio de serviços de saúde. Ao final, todas elas expressaram a vontade de viver, a necessidade de trabalhar, de estudar e, até mesmo, de ter nova gravidez. CONCLUSÕES: Faz-se necessária uma mudança de paradigma nessa missão de atender pessoas; é preciso humanizar o atendimento nos serviços de saúde. Ficou muito evidente a necessidade do acompanhamento de usuárias de serviços de saúde que tiveram uma perda fetal, por uma equipe multiprofissional. Foi evidenciada, também, a import

Avaliação dos modos de falha sob impacto de compósitos de matriz polimérica reforçados por fibras

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Marcelo M. M. Naglis

1998-03-01

Full Text Available RESUMO: Neste trabalho é feita uma avaliação dos modos de falha de compósitos de matriz polimérica reforçados por fibras de vidro, carbono ou aramida, submetidos a carregamento dinâmico. Os compósitos unidirecionais analisados foram fabricados por prensagem e cura à vácuo de lâminas de pré-impregnados. A energia total absorvida na fratura mostrou uma correlação inversamente proporcional ao módulo elástico das fibras usadas como reforço. Os compósitos com fibras de carbono falharam de um modo frágil. Para estes compósitos o comportamento ao impacto pode ser modelado usando-se uma análise puramente elástica. Para os compósitos com fibras de vidro a falha foi controlada por um mecanismo misto de cisalhamento ao longo da interface fibra-matriz e tensão normal trativa atuando perpendicularmente às fibras. O modelo elástico empregado para simular o comportamento ao impacto subestima a energia absorvida por estes compósitos, porém, a diferença entre os valores experimentais e os calculados não ultrapassou 20 %. A falha dos compósitos com fibras aramidas foi atribuída, principalmente, ao componente de tensão trativa atuando perpendicularmente às fibras. Nestes compósitos foi observado arrancamento superficial nas fibras aramidas e o comportamento ao impacto não obedece o modelo elástico empregado.ABSTRACT: In this work an evaluation of the fracture mode of fiber reinforced resin matrix composites submitted to three point bending dynamic impact testing was undertaken. The unidirectional glass, carbon and aramid fiber-epoxy matrix composites used were fabricated by vacuum bagging prepreg laminas. The energy absorbed to fracture the composites had an inverse correlation to the fibres' elastic modulus. The carbon fiber composites failed in a brittle mode. The analysis of the fracture surfaces showed that for the glass fiber composites, the failure is controlled by a coupled mechanism of shear along the fiber

Tatuaje por amalgama. Reporte de un caso

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Luis Fang Mercado

2012-01-01

Full Text Available El tatuaje por amalgama se origina por el depósito en el tejido conectivo subepitelial de fragmentos de amalgama resultado de procedimientos iatrogénicos por parte del operador. La profundidad a la que se encuentren albergados los residuos de este material influye en la presentación clínica de las lesiones. Radiográficamente se pueden identificar los fragmentos mientras tengan diámetros razonables; histológicamente se pueden observar las partículas de amalgama como gránulos oscuros, sólidos e irregulares dispuesto entre los haces de colágeno y vasos sanguíneos. Este artículo refiere el caso clínico de un paciente que presentó pigmentación por amalgama en mucosa vestibular, originada por una porción de amalgama usada como material obturador en una apicectomía del 11 realizada con anterioridad. Teniendo en cuenta las consideraciones clínicas y radiográficas se optó por realizar una segunda apicectomía con obturación retrógrada con MTA del 11. Durante el procedimiento quirúrgico se cureteó y adelgazó la cara interna del colgajo mucoperióstico para tratar de disminuir el grado de pigmentación.

Proton transfer and hydrogen bonding in the organic solid state: a combined XRD/XPS/ssNMR study of 17 organic acid-base complexes.

Science.gov (United States)

Stevens, Joanna S; Byard, Stephen J; Seaton, Colin C; Sadiq, Ghazala; Davey, Roger J; Schroeder, Sven L M

2014-01-21

The properties of nitrogen centres acting either as hydrogen-bond or Brønsted acceptors in solid molecular acid-base complexes have been probed by N 1s X-ray photoelectron spectroscopy (XPS) as well as (15)N solid-state nuclear magnetic resonance (ssNMR) spectroscopy and are interpreted with reference to local crystallographic structure information provided by X-ray diffraction (XRD). We have previously shown that the strong chemical shift of the N 1s binding energy associated with the protonation of nitrogen centres unequivocally distinguishes protonated (salt) from hydrogen-bonded (co-crystal) nitrogen species. This result is further supported by significant ssNMR shifts to low frequency, which occur with proton transfer from the acid to the base component. Generally, only minor chemical shifts occur upon co-crystal formation, unless a strong hydrogen bond is formed. CASTEP density functional theory (DFT) calculations of (15)N ssNMR isotropic chemical shifts correlate well with the experimental data, confirming that computational predictions of H-bond strengths and associated ssNMR chemical shifts allow the identification of salt and co-crystal structures (NMR crystallography). The excellent agreement between the conclusions drawn by XPS and the combined CASTEP/ssNMR investigations opens up a reliable avenue for local structure characterization in molecular systems even in the absence of crystal structure information, for example for non-crystalline or amorphous matter. The range of 17 different systems investigated in this study demonstrates the generic nature of this approach, which will be applicable to many other molecular materials in organic, physical, and materials chemistry.

XPS-UPS, ISS characterization studies and the effect of Pt and K addition on the catalytic properties of MoO{sub 2-x}(OH){sub y} deposited on TiO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Al-Kandari, H. [Public Authority of Applied Education and Training (Kuwait); Mohamed, A.M.; Al-Kharafi, F. [Kuwait University, Department of Chemistry, P.O. Box 5969, Safat 13060 (Kuwait); Katrib, A., E-mail: ali.katrib@ku.edu.kw [Kuwait University, Department of Chemistry, P.O. Box 5969, Safat 13060 (Kuwait)

2011-11-15

Highlights: {yields} Surface electronic structure-catalytic activity correlation is presented in this research work. {yields} In situ characterization by XPS-UPS and ISS techniques were employed at the same experimental conditions applied for catalytic reactions. {yields} Catalytic reactions of Mo deposited on titanium oxide for the isomerization and hydrogenation reactions using 1-hexene and n-hexane were studied. {yields} The bifunctional properties of the molybdenum dioxide phase were modified by the addition of potassium. - Abstract: Characterization by XPS-UPS, ISS surface techniques of MoO{sub 3}/TiO{sub 2} catalysts before and after addition of Pt (PtMo) 2.5% by weight of MoO{sub 3} and potassium (KMo) enabled to identify different chemical species present on the outermost surface layer at different reduction temperatures. Catalytic activities of these systems using 1-hexene and n-hexane reactants were studied. Correlation between catalytic activity and surface electronic structure enabled us to identify the chemical species, active site(s), responsible for specific catalytic reaction(s).

Electronic structure of Ar{sup +} ion-sputtered thin-film MoS{sub 2}: A XPS and IPES study

Energy Technology Data Exchange (ETDEWEB)

Santoni, Antonino, E-mail: antonino.santoni@enea.it [Department FSN-TECFIS-MNF, ENEA, Frascati Research Center, via E. Fermi 45, 00044 Frascati (Italy); Rondino, Flaminia [Department FSN-TECFIS-MNF, ENEA, Frascati Research Center, via E. Fermi 45, 00044 Frascati (Italy); Malerba, Claudia [Department DTE-FSN-TEF, ENEA, Casaccia Research Center, via Anguillarese 301, 00123, Roma (Italy); DICAM, University of Trento, via Mesiano 77, 38123, Trento (Italy); Valentini, Matteo [Department DTE-FSN-TEF, ENEA, Casaccia Research Center, via Anguillarese 301, 00123, Roma (Italy); Department of Physics, University of Rome “Sapienza”, P.le Aldo Moro 5, 00156 Roma (Italy); Mittiga, Alberto [Department DTE-FSN-TEF, ENEA, Casaccia Research Center, via Anguillarese 301, 00123, Roma (Italy)

2017-01-15

Polycrystalline MoS{sub 2} grown by Mo sulphurization was exposed to increasing doses of Ar{sup +} ions at 250 eV starting from 2.2 × 10{sup 15} ions/cm{sup 2} to 3.92 × 10{sup 17} ions/cm{sup 2}. Electronic structure changes were monitored by X-Ray Photoelectron Spectroscopy (XPS) and Inverse Photolectron Spectroscopy (IPES). No change in the Fermi level position was observed with Ar{sup +} dosing. Ion bombardment resulted in a new visible feature at lower binding energy in the Mo3d core level, while the S2p lineshape showed little changes. The formation of a steady state from 2.49 × 10{sup 17} ions/cm{sup 2} has been detected. The investigation of the occupied and unoccupied states on the steady-state surface pointed to the simultaneous presence of metallic-like Mo with amorphous MoS{sub 2-x}.

Thorium effect on the oxidation of uranium: Photoelectron spectroscopy (XPS/UPS) and cyclic voltammetry (CV) investigation on (U1 − xThx)O2 (x = 0 to 1) thin films

NARCIS (Netherlands)

Cakir, P.; Eloirdi, R; Huber, F.; Konings, R.J.M.; Gouder, T

2017-01-01

Thin films of U_1− xTh_xO₂ (x = 0 to 1) have been deposited via reactive DC sputter technique and characterized by X-ray/Ultra-violet Photoelectron Spectroscopy (XPS/UPS), X-ray Powder Diffractometer (XRD) and Cyclic Voltammetry (CV) in order to understand the

La pintura vista por un pintor joven

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Fuentes Pozo, Pedro

2000-01-01

Full Text Available Not available

El pintor se define a lo largo del tiempo como un artista en mutación influenciado por la sociedad de su momento y por su propio mundo interior Esto ha contribuido a la creación de distintos estilos pictóricos y a una evolución que conlleva la despreocupación por el aspecto formal en aras de una introspección al mundo interior En el cambio constante se refleja la búsqueda del artista que valida la intemporalidad del arte. Así, el verdadero artista sobrevive al aplauso o rechazo de la crítica, convirtiéndose en un verdadero hombre renancentista preocupado por el hallazgo del conocimiento universal.

Experiência inicial com terapia por pressão negativa por instilação em feridas complexas

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Dimas André Milcheski

Full Text Available RESUMO Objetivo: relatar a experiência inicial com a terapia por pressão negativa por instilação em feridas complexas infectadas ou contaminadas. Métodos: a terapia por pressão negativa por instilação utilizada foi o V.A.C. Ulta com instilação Veraflo (Kinetic Concepts, Inc. O modo de operação foi contínuo com pressão sub-atmosférica ajustada em 125 mmHg por duas horas e instilação entre as pausas. O tempo de instilação foi de 20 minutos (tempo de contato do agente tópico com a ferida e a substância instilada foi solução salina padrão a 0,9%. Após obtenção de preparo adequado da ferida, ela foi coberta com enxerto ou retalho. Resultados: foram operados dez pacientes com feridas complexas contaminadas ou infectadas. O número médio de trocas da TPNi foi 1,4, o número médio total de cirurgias foi de 2,4, o intervalo até a cobertura da ferida foi de 6,3 dias e o intervalo até a alta foi de 11,4 dias. Conclusão: a comparação da terapia por pressão negativa por instilação com dois estudos prévios (controle histórico evidenciou um tempo de internação menor, favorecendo a TPNi. Este estudo teve um caráter inicial, fazendo-se necessário conduzir um trabalho randomizado e controlado para confirmar a eficácia desta terapia e verificar a sua custo-efetividade.

Neuropatia experimental por DDT: análise de nervo por microdissecção de fibras

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Edison Matos Nóvak

1984-09-01

Full Text Available Estudou-se o nervo gênito-femural do rato albino submetido a intoxicação crônica por DDT, administrado por 180 dias na dose de 5 mg/kg de peso via oral. Os resultados mostraram proporção anormal de fibras tipo C, sendo sugerido ocorrer degeneração tipo axonal determinada pelo DDT.

Ptose palpebral causada por Paquidermoperiostose

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Patricia Regina de Pinho Tavares

2014-08-01

Full Text Available A paquidermoperiostose é uma síndrome caracterizada por acometimento cutâneo e ósseo, e em alguns casos ocorre comprometimento palpebral leve. É uma síndrome rara, idiopática ou hereditária, com provável herança autossômica dominante de penetrância variável. Descreve-se o caso de um paciente com ptose grave por paquidermoperiostose elucidando sua fisiopatologia e conduta cirúrgica aplicada.

Acceptability of sweetened and low calorie dairy desserts: affective tests and internal preference mapping

OpenAIRE

Oliveira, Ana Paula Vital de; Frasson, Karina; Almeida, Tereza Cristina Avancini de; Benassi, Marta de Toledo

2004-01-01

A aceitação de sobremesas lácteas de chocolate (três pudins com açúcar, cinco pudins dietéticos e dois flans comerciais) foi avaliada por 56 consumidores utilizando delineamento de blocos completos balanceados e empregando-se uma escala hedônica estruturada de nove pontos. Os provadores foram caracterizados através de um questionário para coleta de informações pessoais e hábitos de consumo de produtos dietéticos e pudins. Os dados de aceitação foram analisados por ANOVA e teste de médias. Emp...

Desenvolvimento e aplicação do Litterae: um sistema para marcação, etiquetação, estatística e busca de unidades textuais e processuais

OpenAIRE

Daniel Couto Vale

2009-01-01

Esta dissertação, desenvolvida no âmbito do projeto SEGTRAD (Segmentação Cognitiva e Sistemas de Memória de Tradução) e vinculada ao LETRA (Laboratório Experimental de Tradução) da Faculdade de Letras da Universidade Federal de Minas Gerais, propõe um novo método de anotação de registros de teclado (keylog) gravados pelo Translog® com a ferramenta Litterae. Usando os registros do SEGTRAD analisados por Renata R. Rodrigues (2009) de 12 tradutores profissionais nos pares lingüísticos alemão-por...

Torre de Hanói virtual e a constucâo do conceito de funcâo exponencial no ensino médio: um processo que parte da intuicâo a caminho da formalizacâo

OpenAIRE

Breda, Adriana; Hummes, Viviane

2013-01-01

Este trabalho tem como objetivo apresentar uma reflexão sobre o processo de aprendizagem do conceito de Função Exponencial no Ensino Médio, a partir da utilização do jogo Torre de Hanói virtual, através do uso de laptops educacionais. Os dados foram coletados por meio de um questionário inicial, para identificação das ideias prévias dos estudantes e por meio de registros em um diário de campo. Em seguida, os dados foram analisados conforme a metodologia Análise Textual Discursiva. A partir da...

Transformações espaciais na zona costeira : um estudo das relações entre economia, turismo e urbanização no Brasil, Espanha e Marrocos

OpenAIRE

Andréa Máximo Espínola

2013-01-01

Esta tese investiga a correlação entre os ciclos econômicos, os ciclos urbanos e os ciclos turísticos. O litoral foi escolhido como lócus de investigação por apresentar especificidades em sua trajetória econômica e urbana e três estudos de caso foram analisados: Brasil, Espanha e Marrocos. Para abordar o tema proposto optou-se por uma análise baseada em teorias que tratam o ambiente construído como elemento central da dinâmica do capitalismo associados a constante criação de novas localidades...

Vocal complaints and degree of dysphonia in elementary school teachers

OpenAIRE

Azevedo, Luciana Lemos de; Vianello, Luciana; Oliveira, Hellen Glayce Pereira de; Oliveira, Igor de Alvarenga; Oliveira, Bruna Ferreira Valenzuela de; Silva, Carla Menezes da

2009-01-01

OBJETIVO: Realizar o levantamento das queixas vocais e grau de disfonia encontradas em professoras de uma Escola Municipal da Cidade de Betim. MÉTODOS: Foi realizada coleta de dados de 13 professoras do ensino fundamental, com idade entre 20 a 50 anos (média de 36 anos) e carga horária mínima de 20 horas semanais, por meio de questionário aplicado e gravação de voz, no programa de análise acústica GRAM 5.7. Os dados foram analisados e as vozes classificadas por três fonoaudiólogas com experiê...

Ocorrência de fungos em amostras recebidas no laboratório de micologia e proteção de plantas da Universidade Federal de Uberlândia no período de 2001 a 2008

OpenAIRE

Barros, Fernanda Carvalho

2010-01-01

O presente trabalho tem por objetivo relatar a ocorrência de fungos em plantas nas principais culturas de importância econômica na região de Uberlândia, Alto Paranaíba e algumas cidades de Goiás, através da análise dos laudos de amostras de sementes ou partes de plantas encaminhadas ao Laboratório de Micologia e Proteção de Plantas LAMIP, da Universidade Federal de Uberlândia, no período de 2001 a 2008. Os laudos analisados foram separados por cultura e posteriormente foram f...

Vygotsky e a Mediação Computacional no Processo Educacional

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Maria Stela de A. Albuquerque Bergo

2007-06-01

Full Text Available Este artigo aborda a questão da comunicação mediada pelo computador no contexto educacional, tendo por base os conceitos de Vygotsky e Luria, e as abordagens afins que ajudam a explicar o processo e a prever conseqüências dessa prática. O aperfeiçoamento de novos recursos educacionais, desenvolvidos para computadores, bem como o advento da Internet, modificam e sofrem as modificações nas comunicações mediadas por esse novo instrumento. O artigo aponta alguns tópicos a serem analisados pelos interessados sobre o assunto.

Suppression of cytochrome P450 reductase (POR) expression in hepatoma cells replicates the hepatic lipidosis observed in hepatic POR-null mice.

Science.gov (United States)

Porter, Todd D; Banerjee, Subhashis; Stolarczyk, Elzbieta I; Zou, Ling

2011-06-01

Cytochrome P450 reductase (POR) is a microsomal electron transport protein essential to cytochrome P450-mediated drug metabolism and sterol and bile acid synthesis. The conditional deletion of hepatic POR gene expression in mice results in a marked decrease in plasma cholesterol levels counterbalanced by the accumulation of triglycerides in lipid droplets in hepatocytes. To evaluate the role of cholesterol and bile acid synthesis in this hepatic lipidosis, as well as the possible role of lipid transport from peripheral tissues, we developed a stable, small interfering RNA (siRNA)-mediated cell culture model for the suppression of POR. POR mRNA and protein expression were decreased by greater than 50% in McArdle-RH7777 rat hepatoma cells 10 days after transfection with a POR-siRNA expression plasmid, and POR expression was nearly completely extinguished by day 20. Immunofluorescent analysis revealed a marked accumulation of lipid droplets in cells by day 15, accompanied by a nearly 2-fold increase in cellular triglyceride content, replicating the lipidosis seen in hepatic POR-null mouse liver. In contrast, suppression of CYP51A1 (lanosterol demethylase) did not result in lipid accumulation, indicating that loss of cholesterol synthesis is not the basis for this lipidosis. Indeed, addition of cholesterol to the medium appeared to augment the lipidosis in POR-suppressed cells, whereas removal of lipids from the medium reversed the lipidosis. Oxysterols did not accumulate in POR-suppressed cells, discounting a role for liver X receptor in stimulating triglyceride synthesis, but addition of chenodeoxycholate significantly repressed lipid accumulation, suggesting that the absence of bile acids and loss of farnesoid X receptor stimulation lead to excessive triglyceride synthesis.

Consanguinidad por isonimia en Salta

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Albeza, María V.

2007-01-01

Full Text Available Se estimó el coeficiente de parentesco por isonimia para localidades de la Puna, Valle Calchaquí y Valle de Lerma, a fin de evaluar diferentes factores evolutivos que podrían estar afectando la composición genética de la población. A partir de los apellidos de las parejas consignadas en fuentes primarias de información, se estimó la isonimia conyugal o marital, el coeficiente total Ft y sus componentes Fr (inbreeding azaroso y Fn (inbreeding no azaroso. De las localidades estudiadas, en la Puna se ha detectado sólo una pareja isónima en una de ellas, en el Valle Calchaquí, tres y ninguna en el Valle de Lerma. Tanto en el Valle Calchaquí como en el de Lerma, se han estimado valores negativos de Ft, y en la Puna se registran los valores más elevados. En las localidades estudiadas no se cumple el supuesto de transmisión patrilineal de apellidos por lo que los valores de Fr y por ende de Ft podrían estar subestimados. Es por ello que sería necesario contar con información desde otras vertientes metodológicas para corroborar, complementar y manejar cuidadosamente el análisis de los datos y las conclusiones que se obtienen.

Nefrectomía simple por puerto único (LESS) asistida por robot (da Vinci)

OpenAIRE

CASTILLO C,OCTAVIO A; VIDAL M,IVAR; SEPÚLVEDA T,FRANCISCO

2011-01-01

Introducción: La cirugía mínimamente invasiva en urología avanza rápidamente y la cirugía laparo-endoscópica a través de puerto único (LESS) no es la excepción. Esta técnica por vía laparoscópica presenta mucha dificultad y requiere de un cirujano laparoscópico experimentado debido a la falta de triangulación y el cruce de los instrumentos. Los beneficios del sistema quirúrgico da Vinci® han sido introducidos recientemente en LESS. Presentamos dos casos de nefrectomía LESS asistida por robot....

[XPS analysis of beads formed by fuse breaking of electric copper wire].

Science.gov (United States)

Wu, Ying; Meng, Qing-Shan; Wang, Xin-Ming; Gao, Wei; Di, Man

2010-05-01

The in-depth composition of beads formed by fuse breaking of the electric copper wire in different circumstances was studied by XPS with Ar+ ion sputtering. In addition, the measured Auger spectra and the calculated Auger parameters were compared for differentiation of the substances of Cu and Cu2O. Corresponding to the sputtering depth, the molten product on a bead induced directly by fuse breaking of the copper wire without cover may be distinguished as three portions: surface layer with a drastic decrease in carbon content; intermediate layer with a gentle change in oxygen content and gradually diminished carbon peak, and consisting of Cu2O; transition layer without Cu2O and with a rapid decrease in oxygen content. While the molten product on a bead formed by fuse breaking of the copper wire after its insulating cover had been burned out may be distinguished as two portions: surface layer with carbon content decreasing quickly; subsurface layer without Cu2O and with carbon and oxygen content decreasing gradually. Thus, it can be seen that there was an obvious interface between the layered surface product and the substrate for the first type of bead, while as to the second type of bead there was no interface. As a result, the presence of Cu2O and the quantitative results can be used to identify the molten product on a bead induced directly by fuse breaking of the copper wire without cover and the molten product on a bead formed by fuse breaking of the cupper wire after its insulating cover had been burned out, as a complementary technique for the judgments of fire cause.

XPS investigation of monatomic and cluster argon ion sputtering of tantalum pentoxide

Energy Technology Data Exchange (ETDEWEB)

Simpson, Robin, E-mail: r.simpson@surrey.ac.uk [The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, University of Surrey (United Kingdom); Thermo Scientific, East Grinstead (United Kingdom); White, Richard G. [Thermo Scientific, East Grinstead (United Kingdom); Watts, John F.; Baker, Mark A. [The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, University of Surrey (United Kingdom)

2017-05-31

Highlights: • Ion beam induced oxide reduction from monatomic and gas cluster ion beam exposure are compared. • Lower relative level of preferential sputtering is shown in gas cluster ion beam depth profiling. • A lack of “steady state” is observed in gas cluster ion beam depth profiles of tantalum pentoxide. • Possible mechanisms behind the observed results, including temperature effects are proposed. - Abstract: In recent years, gas cluster ion beams (GCIB) have become the cutting edge of ion beam technology to sputter etch organic materials in surface analysis. However, little is currently known on the ability of argon cluster ions (Ar{sub n}{sup +}) to etch metal oxides and other technologically important inorganic compounds and no depth profiles have previously been reported. In this work, XPS depth profiles through a certified (European standard BCR-261T) 30 nm thick Ta{sub 2}O{sub 5} layer grown on Ta foil using monatomic Ar{sup +} and Ar{sub 1000}{sup +} cluster ions have been performed at different incident energies. The preferential sputtering of oxygen induced using 6 keV Ar{sub 1000}{sup +} ions is lower relative to 3 keV and 500 eV Ar{sup +} ions. Ar{sup +} ions exhibit a steady state O/Ta ratio through the bulk oxide but Ar{sub 1000}{sup +} ions show a gradual decrease in the O/Ta ratio as a function of depth. The depth resolution and etch rate is substantially better for the monatomic beam compared to the cluster beam. Higher O concentrations are observed when the underlying Ta bulk metal is sputtered for the Ar{sub 1000}{sup +} profiles compared to the Ar{sup +} profiles.

Análisis de costos por ausentismo laboral atribuibles a licencias médicas por enfermedad. Hospital Nacional Arzobispo Loayza 2015

OpenAIRE

Jave Escalante, Gladys Lizeth

2015-01-01

Determina el costo generado por el ausentismo laboral atribuible a licencias médicas por enfermedad en el Hospital Nacional Arzobispo Loayza 2015. METODOLOGÍA: Estudio no experimental. La muestra estuvo conformada por 118 médicos asistenciales y personal de enfermería. Para el análisis de los costos se utilizó el costo de tiempo perdido del paciente, ingresos dejados de percibir por el hospital y descuento económico al trabajador. Además se realizó un análisis económico y de sensibilidad. ...

AS DIFERENTES REPRESENTAÇÕES SEMIÓTICAS ELABORADAS POR CRIANÇAS DO ENSINO FUNDAMENTAL UTILIZANDO JOGOS DIGITAIS. DIFFERENT SEMIOTIC REPRESENTATIONS PRODUCED BY ELEMENTARY SCHOOL CHILDREN FROM DIGITAL GAMES

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Valdinei Cezar Cardoso

2013-11-01

Full Text Available A Teoria das Representações Semióticas de Duval foi o referencial teórico norteador desta pesquisa, que teve como objetivo principal identificar, por meio de registros obtidos em atividades mediadas por jogos digitais, as possíveis representações mentais elaboradas por crianças do primeiro ano do Ensino Fundamental. A coleta de dados, feita durante o trabalho de conclusão de um curso de Pedagogia, deu-se por meio de gravações em vídeo e de registros escritos produzidos pelos estudantes. A análise dos dados identificou a elaboração e a manifestação de representações de conceitos matemáticos. Os dados foram analisados de acordo com a proposta de Henry (2006 e sob as lentes da teoria de Duval (2003. Os resultados apontam que os diversos registros apresentados pelos estudantes têm uma estreita relação com as competências desenvolvidas durante o jogo e a resolução de atividades escritas na mesma categoria. Dessa forma, esta pesquisa possibilita o estudo de situações nas quais os estudantes precisam interpretar e converter diferentes tipos de representações semióticas, a fim de compreender o complexo processo da construção de conceitos matemáticos pelas crianças. Duval’s Semiotic Representations Theory was the guiding theoretical reference to the present research, which mainly focused on identifying the possible mental representations elaborated by first grade students of Elementary School, by means of records obtained in activities mediated by digital games. The data collection methods, carried out as a research at the Pedagogy undergraduate level as a requirement for graduation were video recordings and written registers produced by students. The data analysis identified the formulation and manifestation of mathematical concepts representations. The data were analyzed according to the methodology proposed by Henry (2006, under Duval’s theory (2003, and the results indicated that the registers presented by

Indice por Materias

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Montoya H Luz Marina

1982-09-01

Full Text Available Un índice es una lista de palabras o frases indicadores asociados que permite la ubicación de material al interior de un libro o una publicación, en este caso será por el nombre de la materia.

Análise e reflexão sobre a educação especial inclusivo em Maringá/BR e em Guadalajara/ES

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Maria de Jesus Cano Miranda

2013-12-01

Full Text Available O objetivo do presente estudo é conhecer o percurso da Educação Especial em contextos distintos, cidade de Maringá/Brasil e Guadalajara/Espanha e analisar as bases que fundamentam a organização, estrutura e o funcionamento dessa modalidade de ensino tendo como ponto de partida o processo de escola inclusiva. Os pressupostos que embasam este trabalho fundamentam-se na concepção Histórico Cultural proposta por Vygotski que defende a existência de princípios essenciais que embasam o desenvolvimento da criança com deficiência. Se, por um lado, a deficiência impõe limitações ao indivíduo, dificultando seu desenvolvimento, por outro, justamente por ocasionar dificuldades, possibilita o movimento para a compensação, ampliando o desenvolvimento de outras capacidades. O déficit em si é o de menos. Portanto, trata-se de uma pesquisa de campo, realizada por meio de observações, pesquisa na literatura e análise documental em instituições de educação infantil visitadas, nas cidades já referidas. Os resultados mostraram que há peculiaridades quanto ao percurso, organização e funcionamento da Educação Especial em cada um dos contextos analisados. Referentemente ao movimento de educação inclusiva, evidencia-se que a Espanha é precursora desse processo, por consequência apresenta condições adequadas nas diferentes formas de conduzir o atendimento às crianças com necessidades especiais, e por outro lado, as escolas dispõem dos recursos humanos e materiais especializados de que necessitam. Enquanto no Brasil a operacionalização dessas medidas ocorre mais lentamente. Assim, podese dizer que esse processo de educação inclusiva não acontece de forma linear dentro das escolas regulares e tão pouco nas diferentes formas de ação da educação especial nos dois contextos analisados.

Mortalidad intrahospitalaria por accidente cerebrovascular

OpenAIRE

Federico Rodríguez Lucci; Virginia Pujol Lereis; Sebastián Ameriso; Guillermo Povedano; María F. Díaz; Alejandro Hlavnicka; Néstor A. Wainsztein; Sebastián F. Ameriso

2013-01-01

La mortalidad global por accidente cerebrovascular (ACV) ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Str...

Fatores associados ao acesso anterior à gestação a serviços de saúde por adolescentes gestantes Factores asociados con el acceso anterior a la gestación a los servicios de salud por adolescentes gestantes Factors associated with access to health services prior to pregnancy by pregnant adolescents

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Ingrid Espejo Carvacho

2008-10-01

Full Text Available OBJETIVO: Analisar os fatores determinantes do acesso de adolescentes gestantes a serviços de atenção primária à saúde, anterior à ocorrência da gestação. MÉTODOS: Estudo transversal baseado em referencial teórico. O acesso a serviços foi analisado em cinco dimensões: geográfico, econômico, administrativo, psicossocial e de informação. Participaram 200 adolescentes primigestas (10 a 19 anos atendidas em uma unidade básica de saúde do município de Indaiatuba (SP, em 2003. Um questionário com perguntas abertas e fechadas referentes ao acesso ao último serviço de saúde utilizado, anterior à gestação, foi aplicado às participantes no momento de sua primeira consulta de pré-natal. Os dados foram analisados por meio do teste de qui-quadrado de Pearson ou exato de Fisher e por regressão logística múltipla, considerando as cinco dimensões de acesso. RESULTADOS: Mais da metade (63,7% das adolescentes utilizou algum serviço de saúde para consulta ginecológica. Entre as que nunca consultaram um ginecologista, as justificativas dadas foram falta de informação (43,8% ou sentimento de medo ou vergonha (37,0%. A principal dificuldade de acesso ao serviço esteve relacionada a barreiras psicossociais, identificadas por 77,0% das adolescentes. CONCLUSÕES: Entre as barreiras de acesso ao serviço de saúde, foram significativas apenas as psicossociais. São necessárias novas estratégias para facilitar o acesso ao serviço de saúde às adolescentes, incluindo ações que diminuam as barreiras de gênero e que se considerem suas características sociodemográficas e o vínculo com seus parceiros.OBJETIVO: Analizar los factores determinantes del acceso de adolescentes gestantes a los servicios de atención primaria a la salud, anterior a la ocurrencia de la gestación. MÉTODOS: Se efectuó estudio transversal basado en referencial teórico. El acceso a servicios fue analizado en cinco dimensiones: geográfico, econ

Corrosion inhibition performance of 2,5-bis(4-dimethylaminophenyl)-1,3,4-oxadiazole for carbon steel in HCl solution: Gravimetric, electrochemical and XPS studies

Energy Technology Data Exchange (ETDEWEB)

Bouanis, M.; Tourabi, M.; Nyassi, A. [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Zarrouk, A. [LCAE-URAC 18, Faculty of Science, First Mohammed University, PO Box 717, M-60 000 Oujda (Morocco); Jama, C. [UMET-ISP, CNRS UMR 8207, ENSCL, Université Lille Nord de France, CS 90108, F-59652 Villeneuve d' Ascq Cedex (France); Bentiss, F., E-mail: fbentiss@gmail.com [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); UMET-ISP, CNRS UMR 8207, ENSCL, Université Lille Nord de France, CS 90108, F-59652 Villeneuve d' Ascq Cedex (France)

2016-12-15

Highlights: • 2,5-Bis(4-dimethylaminophenyl)-1,3,4-oxadiazole is good corrosion inhibitor for carbon steel in 1 M HCl. • XPS analysis has provided the composition of adsorbed protective layer on the steel surface. • The adsorption of the investigated 1,3,4-oxadiazole is mainly due to chemisorption. - Abstract: Corrosion inhibition of carbon steel in normal hydrochloric acid solution at 30 °C by 2,5-bis(4-dimethylaminophenyl)-1,3,4-oxadiazole (DAPO) has been studied by weight loss measurements and electrochemical techniques (polarization and AC impedance). The experimental results showed that DAPO acted as an efficient inhibitor against the carbon steel corrosion in 1 M HCl, and its inhibition efficiency increased with the inhibitor concentration reaching a value up to 93% at 1 mM. Polarization studies showed that the DAPO was a mixed-type inhibitor. The adsorption of this 1,3,4-oxadiazole derivative on the carbon steel surface in 1 M HCl solution followed the Langmuir adsorption isotherm and the corresponding value of the standard Gibbs free energy of adsorption (ΔG°{sub ads}) is associated to a chemisorption mechanism. Scanning Electron Microscopy (SEM) and X-Ray Photoelectron Spectroscopy (XPS) analyses were carried out to characterize the chemical composition of the inhibitive film formed on the steel surface. The surfaces studies showed that the inhibitive layer is composed of an iron oxide/hydroxide mixture where DAPO molecules are incorporated. The cytotoxicity of DAPO was also determined using cell culture system.

Avaliação postural por fotogrametria em pacientes com escoliose idiopática submetidos à artrodese: estudo piloto

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Lucas de Macedo dos Santos

Full Text Available INTRODUÇÃO: A escoliose é uma alteração tridimensional das vértebras, caracterizada por um desvio lateral. A quantificação do desvio lateral após correção cirúrgica poderia auxiliar quanto ao prognóstico da doença e direcionar na reabilitação. OBJETIVOS: Comparar as alterações posturais no pré e pós-operatório de artrodese da coluna vertebral em pacientes com escoliose idiopática do adolescente. MATERIAIS E MÉTODOS: Foram avaliados nove pacientes com escoliose idiopática entre 11 e 18 anos de idade. Eles foram fotografados no pré-operatório e após quatro semanas. Os pontos anatômicos foram marcados sobre a pele por meio de fixação de bolas de isopor. Para análise das fotografias, estas foram enviadas para um computador com o programa SAPO previamente instalado. Os dados foram analisados utilizando o teste t pareado. RESULTADOS: Foram observados: diminuição significante no ângulo axilar esquerdo (EACE e no ângulo Q esquerdo (AQE, aumento no ângulo de inclinação do tronco na vista anterior (ITA, no ângulo formado entre o ponto mais alto do trapézio e o manúbrio esquerdo (TAME, no ângulo da cifose torácica direita (CTD e lordose lombar direita e esquerda (LLD e LLE e no ângulo tibiotársico esquerdo (ATTE. Houve aumento nas distâncias entre C7, T3 e T7 à espinha ilíaca póstero-superior direita (DC7, DT3 e T7 e C7, T3 e L4 à espinha ilíaca póstero-superior esquerda (EC7, ET3 e EL4. CONCLUSÃO: Foi constatada alteração significativa nos ângulos EACE, AQE, ITA, TAME, CTD, LLD, LLE, ATTE e nas distâncias DC7, DT3, DT7, EC7, ET3 e EL4 quatro semanas após a cirurgia de artrodese.

CARACTERÍSTICAS DA VIOLÊNCIA SEXUAL SOFRIDA POR CRIANÇAS ASSISTIDAS POR UM PROGRAMA DE APOIO

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KELLY LINHARES VASCONCELOS

2010-01-01

Full Text Available En Brasil, las estadísticas de la violencia sexual contra niños están lejos de reflejar la verdadera realidad actual debido a la baja notificación de los casos. La finalidad de este estudio fue caracterizar el abuso sexual sufrido por niños asistidos por el Programa Sentinela y el perfil del agresor, en Sobral-Ceará, en el periodo que va del 2002 al 2006. La muestra no probabilística intencional fue compuesta por 50 víctimas de abuso sexual y de las mismas, el 66% es del sexo femenino, con predominio de rango de edad entre 8-12 años incompletos, (58%; en el 36% de los casos los padres están separados, siendo la madre la principal responsable por la familia (62%. La mayoría de los agresores es del sexo masculino (78%. En el ambiente fuera de la familia los agresores son conocidos o amigos de la familia (14%; dentro del seno familiar el padrastro es identificado como siendo el agresor más frecuente (18%. Los datos destacan características similares a las de otros estudios, definiendo una cierta igualdad en este tipo de violencia.

Application of XPS and nuclear technique to the study of the gel layers formed under different redex conditions on leached glasses

International Nuclear Information System (INIS)

Manara, A.; Lanza, F.; Ceccone, G.; Della Mea, G.; Salvagno, G.

1984-01-01

Surface analysis has been conducted on samples leached in a Soxhlet apparatus at 100 0 C in presence and in absence of air. The XPS and RBS techniques were applied to analyse the content of the silicon, iron and uranium while the nuclear reaction method was utilized to analyse the hydrogen content. The anoxic environment favors the release of iron while decreasing the dissolution of uranium. Hydrogen content is always higher in samples leached in presence of air. Silicon depletion is evident in all cases. The diffusion process seems to regulate the growth of the layer on the glass surface. After long leaching time a detachment, at least partial, of this layer is observed. 14 refs., 9 figs., 1 tab

Anos potenciais de vida perdidos por mulheres vítimas de homicídio na cidade do Recife, Pernambuco, Brasil Years of potential life lost by female homicide victims in Recife, Pernambuco State, Brazil

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Leonildo Severino da Silva

2011-09-01

Full Text Available Estudo epidemiológico, transversal, objetivando calcular os anos potenciais de vida perdidos por mulheres vítimas de homicídio na cidade do Recife, Pernambuco, Brasil, no quinquênio 2003-2007. Utilizou-se de um banco de dados da Gerência Operacional de Informação de Mortalidade e Natalidade da Secretaria de Saúde do Recife, e foram revisadas todas as declarações de óbitos das vítimas de homicídio, com idade fértil no quinquênio analisado. Os resultados revelaram que houve 12.120 anos potenciais de vida perdidos, no período, por mulheres jovens, negras (88%, de escolaridade desconhecida (78,2%, solteiras (80%, mortas na Região Político-administrativa III, que foram assassinadas com uso de arma de fogo, no próprio domicílio. A taxa de mortalidade específica, no período, correspondeu a 10,8 por 100 mil mulheres em idade fértil. Os 43,3 anos de vida perdidos por cada vítima refletem, entre outros aspectos, as características do município, relativas ao nível de pobreza, desemprego, densidade populacional, instabilidade residencial, desigualdade social, que expõem seus habitantes a crises sociais, crimes e violência.This cross-sectional epidemiological study aimed to calculate the potential years of life lost by female homicide victims in Recife, Pernambuco State, Brazil, in 2003-2007. A database was used from the Operational Division for Information on Births and Deaths under the Recife Municipal Health Department. All death certificates for childbearing-age women were reviewed for the five-year period. The results showed a total of 12,120 potential years of life lost by these women, mostly young, black (88%, with unknown levels of schooling (78.2%, single (80%, in District III of the city, and murdered with firearms in their own homes. The specific mortality rate was 10.8 homicides per 100,000 childbearing-age women. The 43.3 years of life lost per woman express the city's characteristics, poverty levels, unemployment

Análise da eficiência energética nos países do BRICS: um estudo envolvendo a Análise por Envoltória de Dados

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Flávia de Castro Camioto

2015-01-01

Full Text Available Num período de mudanças climáticas e restrições a emissões cada vez maiores, é importante focar o desenvolvimento das nações na direção de uma economia de baixo carbono. Neste contexto, o crescimento do consumo de energia tornou-se um problema grave; logo, medidas que garantam a eficiência energética tornaram-se prioritárias para qualquer nação que esteja disposta a desenvolver sua economia. Considerando que o grupo do BRICS tem apresentado rápido desenvolvimento econômico e desempenhado importante papel na economia mundial, este trabalho teve como principal objetivo medir e analisar a eficiência energética total de fatores nos países que compõem o BRICS (Brasil, Rússia, Índia, China e África do Sul, propiciando informações sobre países benchmark dentro desse grupo e sobre como o Brasil se encontra nesse cenário. Para isso, foi utilizada a Análise Envoltória de Dados (DEA, modelo SBM variante e análise de janela, e, a partir das folgas fornecidas por esta ferramenta, foi calculado o índice de eficiência energética total de fatores (EETF para os países analisados. Como inputs foram utilizados a formação bruta de capital fixo, trabalho e consumo energético e como outputs, a emissão de CO2(output indesejável e o Produto Interno Bruto – PIB (outputdesejável. A partir dos resultados, observou-se que o Brasil é o país com melhor índice de EETF dentro do BRICS, seguido por África do Sul, China, Índia e Rússia.

ESTRATÉGIAS PEDAGÓGICAS EMPREGADAS POR PROFESSORES DE EDUCAÇÃO ESPECIAL AOS SEUS ALUNOS COM DEFICIÊNCIA INTELECTUAL SEVERA: UM ESTUDO DESCRITIVO DA PRÁTICA DOCENTE

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Patricia Moralis CARAMORI

2015-12-01

Full Text Available RESUMO Esta pesquisa aborda a temática da educação de indivíduos com deficiência intelectual severa a partir das estratégias pedagógicas utilizadas por professoras de Educação Especial. Justifica-se por abordar o processo educacional de uma população pouco investigada, além de unir dois eixos de discussão de forma inovadora: a Teoria da Modificabilidade Cognitiva Estrutural (MCE de Reuven Feuerstein e a educação de alunos severamente prejudicados. Segundo essa Teoria, o professor atua como mediador, interpondo-se entre os estímulos do ambiente e o aluno. Seu objetivo pauta-se na descrição e análise da implementação do processo educacional de alunos com deficiência intelectual severa, enfocando as estratégias pedagógicas de professoras de Educação Especial na cidade de Araraquara. Os procedimentos iniciais indicam o estabelecimento dos perfis das professoras, seu mapeamento e localização. Definidos os participantes, a coleta dos dados se deu por meio de três instrumentos: entrevista semiestruturada realizada com as professoras e observação, registrada em protocolo e em diário de campo. Os dados foram analisados qualitativamente a fim de permitir a extração de detalhes do cotidiano observado. Os resultados apresentam uma descrição do trabalho das quatro professoras participantes, evidenciando suas opiniões sobre suas práticas, além de arrolar as estratégias pedagógicas utilizadas. Oferece-se como conclusão a identificação de estratégias pedagógicas que se relacionam com os critérios que regem a mediação. Isso mostra que é possível associar as idéias de Feuerstein às práticas pedagógicas voltadas aos alunos com deficiência intelectual severa, já que determinados procedimentos empregados demonstram trazer em seu cerne alguns preceitos essenciais à mediação.

Angle-dependent XPS study of the mechanisms of 'high-low temperature' activation of GaAs photocathode

International Nuclear Information System (INIS)

Du Xiaoqing; Chang Benkang

2005-01-01

The surface chemical compositions, atomic concentration percentage and layer thickness after 'high-temperature' single-step activation and 'high-low temperature' two-step activation were obtained using quantitative analysis of angle-dependent X-ray photoelectron spectroscopy (XPS). It was found that compared to single-step activation, the thickness of GaAs-O interface barrier had a remarkable decrease, the degree of As-O bond became much smaller and the Ga-O bond became dominating, and at the same time the thickness of (Cs, O) layer also had a deduction while the ratio of Cs to O had no change after two-step activation. The measured spectral response curves showed that a increase of 29% of sensitivity had been obtained after two-step activation. To explore the inherent mechanisms of influences of the evolution of GaAs(Cs, O) surface layers on photoemission, surface electric barrier models based on the experimental results were built. By calculation of electron escape probability it was found that the decrease of thickness of GaAs-O interface barrier and (Cs, O) layer is the main reasons, which explained why higher sensitivity is achieved after two-step activation than single-step activation

Characterization study of native oxides on GaAs(100) surface by XPS

Science.gov (United States)

Feng, Liu; Zhang, Lian-dong; Liu, Hui; Gao, Xiang; Miao, Zhuang; Cheng, Hong-chang; Wang, Long; Niu, Sen

2013-08-01

In order to know more about the surface state of GaAs(100) epitaxial wafer during a storage period of two years, the XPS analysis was carried out four times on the surface, respectively polished by chemical etching, stored in desiccator for half a year, one year and two years. The results indicated that even after cleaned by proper etchant solutions, the fresh surface was slightly oxidized with Ga2O3, As2O3 and organic contaminant. The epi-wafer was always exposed to air during the storage period, so more and more oxides turned out. The mixed oxide layer comprised of C-OR, COOR, Ga2O3, As2O3 and As2O5 appeared after only half a year. In the ageing process of two years, the oxide types of gallium or arsenic did not change with stable content of Ga2O3 and remarkably fluctuating relative contents of As2O3 and As2O5. Based on the intensity ratio of Ga 3d-Ga2O3 to Ga 3d-GaAs, the thickness of oxide layer was estimated. The oxide layer generated after chemical polishing was very thin, just only 0.435nm thick, and then it grew rapidly, approximately 1.822nm after one year while almost no change any more subsequently. It was indicated that after the epi-wafer was stored for one year, because of volatile As2O3 or As2O5, there remained a large amount of Ga2O3 in oxide layer, which prevented the reactions between bulk material and oxide layer with oxygen. So native oxide layer plays a role as passive film to protect epi-wafer against the environment during a long storage period.

Vivencias psicosociales reveladas por niños que reciben tratamiento con quimioterapia por cáncer

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BLANCA CECILIA VANEGAS DE AHOGADO

2009-12-01

Full Text Available Se realizó un estudio cualitativo con el propósito de descubrir las vivencias psicosociales de niños y niñas de 9 a 12 años que recibían tratamiento con quimioterapia por cáncer. La recolección de la información se hizo mediante encuentros lúdicos con el apoyo de algunas preguntas básicas que facilitaron las revelaciones narrativas. Tres aspectos se destacan en los hallazgos del estudio: vivencias desfavorables, vivencias relacionadas con la autoestima y vivencias favorables; las dos primeras, de diversa manera, afectan en estos niños su vida personal, familiar, escolar y, en general, todo su entorno. Es de resaltar que, como consecuencia de la caída del cabello, con frecuencia han sido objeto de burla y de rechazo por sus compañeros de estudio, lo que produce el más notorio efecto sobre su autoimagen; por otra parte, el ausentismo escolar conlleva dificultades académicas y sentimientos de tristeza en estos niños, situación que empeora cuando, por motivos de tratamiento, su lugar de residencia está alejado de la ciudad, viéndose sometidos a largos periodos de separación, no solo de su familia sino de sus pares. Se concluye que la mayor parte de las revelaciones son impactantes por su gran contenido de sufrimiento y dolor para estos niños, lo que demuestra la urgencia de retomar los hallazgos del estudio para orientar el cuidado de enfermería de manera más integral y apoyar para que se haga lo propio en el hogar y en las instituciones educativas.

ESTRUTURALISTA, PÓS-ESTRUTURALISTA OU PÓS-MODERNO? APROPRIAÇÕES DO PENSAMENTO DE MICHEL FOUCAULT POR PESQUISADORES DA ÁREA DE ADMINISTRAÇÃO NO BRASIL

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Alessandra de Sá Mello Costa

2012-06-01

Full Text Available O presente artigo busca identificar as aproximações e os afastamentos entre as abordagens estruturalistas, pós-estruturalistas e pós-modernistas por meio da investigação das categorizações epistemológicas do pensamento de Michel Foucault feitas por pesquisadores da área de administração no Brasil. Os procedimentos metodológicos de investigação foram divididos em dois momentos. Primeiro, foram pesquisados os artigos publicados nos últimos dez anos nos anais de dois dos mais representativos encontros científicos da academia de administração no Brasil: o Encontro Nacional da ANPAD (EnANPAD, encontro anual, e o Encontro de Estudos Organizacionais (EnEO, que ocorre de dois em dois anos. A pesquisa foi feita nos artigos que referenciavam Michel Foucault no título ou no escopo do resumo. No que diz respeito ao número de ocorrências encontradas, os resultados obtidos totalizaram 41 artigos. Em um segundo momento, após a identificação dos artigos, estes foram lidos e analisados de forma a identificar como Michel Foucault é categorizado por cada um dos pesquisadores em questão. Os resultados obtidos na pesquisa levam a crer que as questões epistemológicas ainda não fazem parte do corpo de preocupações de grande parte dos pesquisadores brasileiros na área de administração. Tal ausência apresenta-se, ao mesmo tempo, significativa e preocupante. Significativa, porque mostra que os pesquisadores brasileiros não estão preocupados com o contexto teórico de produção e disseminação das idéias, incorporando-as como verdades em suas pesquisas de forma descontextualizada e acrítica. E preocupante, uma vez que a luta por poder no campo das idéias não significa apenas um embate em torno dos melhores postos acadêmicos, posições institucionais e governamentais de financiamento ou um lugar de destaque nos comitês editoriais dos periódicos mais influentes. O perigo reside em uma dimensão complementar e inerente a essa

Wavefront-guided refractive surgery results of training-surgeons Resultados das cirurgias refrativas guiadas por frentes de ondas de cirurgiões em treinamento

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Iane Stillitano

2010-08-01

Full Text Available PURPOSE: To assess clinical outcomes and changes on higher-order aberrations (HOA after wavefront-guided laser in situ keratomileusis (LASIK and photorefractive keratectomy (PRK for correction of myopia and myopic astigmatism performed by training-surgeons. METHODS: One hundred and seventy patients had customized LASIK (207 eyes and PRK (103 eyes performed by surgeons in-training using the LADARVision 4000 (Alcon, Fort Worth, TX. Preoperative and 1, 3, 6 and 12 months postoperative data of spherical equivalent (SE, best spectacle-corrected visual acuity (BSCVA and uncorrected visual acuity (UCVA were analysed. Wavefront changes were determined using the LADARWave Hartmann-Shack wavefront aberrometer and the pupil size was scaled for 6.5 mm. RESULTS: The mean SE in the LASIK group was -3.04 ±1.07 D and in the PRK group was -1.60 ± 0.59 D. At 1-year follow-up, (80.6% (LASIK and (66.7% (PRK were within ± 0.50 D of the intended refraction. The UCVA was 20/20 or better in (58.1% (LASIK and (66.7% (PRK of the operated eyes. A statistically significant positive correlation was found between achieved versus attempted refractive correction in both groups: LASIK (r=0.975, POBJETIVO: Avaliar os resultados clínicos e mudanças nas aberrações de alta-ordem (HOA, após ceratomileuse assistida por excimer laser in situ (LASIK e ceratectomia fotorrefrativa (PRK guiados por frentes de onda para correção da miopia e astigmatismo miópico realizada por cirurgiões em treinamento. MÉTODOS: Estudo prospectivo de 170 pacientes submetidos a LASIK personalizado (207 olhos e PRK (103 olhos realizados por cirurgiões em treinamento utilizando o LADARVision 4000 (Alcon, Fort Worth, TX. Dados do equivalente esférico (SE, melhor acuidade visual corrigida (BSCVA e acuidade visual não corrigida (UCVA foram analisados no pré-operatório e com 1, 3, 6 e 12 meses de pós-operatório. As alterações de frentes de onda foram determinadas usando o aberrômetro Hartmann

Pedro Teixeira y su viaje por Mesopotamia

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Fuente del Pilar, José Javier

2005-04-01

Full Text Available Pedro Teixeira es un integrante notable de la ilustre nómina de los viajeros portugueses que, a finales del s, XVI y principios del XVII, ensancharon para Occidente las fronteras del mundo. Su conocimiento en España se debe a la publicación en 1994 de su obra «Relaciones del Origen, Descendencia y Sucesión de los Reyes de Persia, y de Harmuz, y de un viaje hecho por el autor dende la India hasta Italia por tierra», en edición realizada por el profesor Eduardo Barajas Sala, lamentablemente fallecido en 1997. En este artículo se ofrece una reseña biográfica de Pedro Teixeira, y un análisis del viaje narrado por el autor en la última parte de sus «Relaciones »: el que desde Ormuz le conducirá, a través de Mesopotamia, hasta la costa del Mediterráneo.…

Violência e mortes por causas externas

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Graciete Oliveira Vieira

2003-02-01

Full Text Available Através de um estudo ecológico caracterizou-se a violência e as mortes por causas externas em Salvador e Bahia utilizando-se dados da Fundação Nacional de Saúde-Ministério da Saúde, dos registros de mortalidade e das estimativas populacionais do IBGE. O risco de morrer por homicídio no Brasil é 3 vezes o do Estados Unidos, chegando a ser 40 vezes superior ao do Japão. Homicídio foi a primeira causa de anos potenciais de vidas perdidos (13,4% no Brasil (1997, seguido por acidentes de trânsito (10,6%. Causas externas foi a segunda causa de morte em Salvador e Bahia (1996. A violência tem raízes sócio-culturais e político-ideológicas e pode ser prevenida por ações intersetoriais e multidisciplinares.

Associação entre violência por parceiro íntimo contra a mulher e infecção por HIV

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Claudia Barros

2011-04-01

Full Text Available OBJETIVO: Analisar a associação entre a violência por parceiro íntimo contra mulheres e a infecção ou suspeita de infecção pelo vírus da imunodeficiência humana (HIV. MÉTODOS: Estudo transversal com base em dados de questionários aplicados face-a-face e de prontuários médicos de 2.780 mulheres de 15 a 49 anos, atendidas em unidades do sistema único de saúde da Grande São Paulo, SP, em 2001-2002. As mulheres foram categorizadas em: usuárias em tratamento por serem "soropositivas para o HIV", com "suspeita de HIV" e aquelas que procuraram os serviços por outros motivos. A violência por parceiro íntimo contra mulheres na vida foi categorizada por gravidade e recorrência dos episódios de violência. A associação com o desfecho foi testada pelo modelo de Poisson com variância robusta e ajustada por variáveis sociodemográficas, sexuais e reprodutivas. RESULTADOS: A prevalência de violência foi de 59,8%. Sofrer violência reiterada e grave apresentou maior associação de infecção confirmada pelo HIV (RP = 1,91. A violência independente da gravidade e da recorrência dos episódios apresentou maior associação para a suspeita de infecção por HIV (RP = 1,29. CONCLUSÕES: A violência por parceiro íntimo contra mulheres tem papel relevante nas situações de suspeita e confirmação da infecção pelo HIV, sendo essencial incluir sua detecção, controle e prevenção como parte da atenção integral à saúde das mulheres.

Predominant porB1A and porB1B genotypes and correlation of gene mutations with drug resistance in Neisseria gonorrhoeae isolates in Eastern China

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Tang Renxian

2010-11-01

Full Text Available Abstract Background Variations of porB1A and porB1B genes and their serotypes exist in Neisseria gonorrhoeae isolates from different geographical areas, and some site mutations in the porB1B gene correlate with drug resistance. Methods The β-lactamase production of N. gonorrhoeae isolates was determined by paper acidometric test and nitrocefin discs. The porB1A and porB1B genes of 315 non-penicillinase-producting N. gonorrhoeae (non-PPNG strains were amplified by PCR for sequencing to determine serotypes and site mutations. A duplex PCR was designed to simultaneously detect both porB1A and porB1B genes. Penicillin and tetracycline resistance was assessed by an in vitro drug sensitivity test. Results Of the N. gonorrhoeae isolates, 31.1% tested positive for porB1A and 68.9% for porB1B genes. All the 98 porB1A+ isolates belonging to IA6 serotype with either no mutation at the 120 and 121 sites (88.8% or a D120G (11.2% mutation and were no resistance to both penicillin and tetracycline. Among the 217 porB1B+ isolates, 26.7%, 22.6% and 11.5% belonged to IB3, IB3/6 and IB4 serotypes, respectively. Particularly, two novel chimeric serotypes, IB3/6-IB2 and IB2-IB4-IB2, were found in 77 and 8 porB1B+ isolates. Two hundred and twelve (97.7% of the porB1B+ isolates were presented G120 and/or A121 mutations with 163 (76.9% at both sites. Interestingly, within the 77 porB1B+ isolates belonging to IB3/6-IB2 serotype, 15 were discovered to possess novel deletions at both A121 and N122 sites. All the replacement mutations at these sites in PorB1B were correlated with resistance and the deletion mutation showed the highest resistance. Conclusion N. gonorrhoeae isolates circulating in Eastern China include a sole PorB1A serotype (IA6 and five PorB1B serotypes. Multiple mutations in porB1B genes, including novel A121 and N122 deletions, are correlated with high levels of penicillin and tetracycline resistance.

Propiedades fisicoquimicas de sistemas La/TiO2 empleados en la fotodegradación de 2-nitrofenol con luz visible en un simulador solar

OpenAIRE

Giuliante, Adriana; Marrero, Santiago; Carrillo, Valentina; Fuentes, Keyla; Albornoz, Alberto; Brito, Joaquín; Betancourt, Paulino

2011-01-01

Una serie de sólidos de La/TiO2 fueron preparados empleando un método de impregnación convencional. Estas muestras fueron caracterizadas por difracción de rayos X, adsorción de nitrógeno, determinación del punto de carga cero, adsorción de piridina seguida por FTIR y espectroscopía fotoelectrónica de rayos-X (XPS). Los resultados arrojados por dichas técnicas indicaron que la presencia de La como dopante acelera parcialmente la transformación de fase anatasa a rutilo al incorporar 1% del meta...

Conservación por calor

OpenAIRE

Cobos García, Angel; Díaz Rubio, Olga

2011-01-01

Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

Las cosas por su nombre

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Storani, Emilia

2017-01-01

El artículo propone indagar sobre los modos y diferentes formatos que se utilizan tanto en la escritura como en la lectura, para articular con las luchas por la identidad de género. La Ley de Identidad de Género ha sido un puntapié clave para pensarnos a nosotros mismos culturalmente y para pensar a los demás. Pero, ¿cómo mencionamos, escribimos y leemos las diferentes identidades? La escritura, también es un mundo transformador para quienes bregan por una sociedad más libre y sin prejuicios....

Diverticulitis yeyunal perforada por enterolito.

OpenAIRE

Marenco De la Cuadra, Beatriz; Gomez-Rosado, Juan-Carlos; Capitan-Morales, Luis-Cristobal; Valdés Hernández, Javier; Reyes-lopera, N.J. De los

2012-01-01

La diverticulosis yeyunal es una enfermedad adquirida rara. Casi el 60-70% keeps asymptomátic or Con síntomas crónicos inespecíficos, aunque puede presentarse como un abdomen agudo. La perforación debida a enterolitos es una causa extremadamente rara do complicación, y puede producirse por la impactación de ésta contra la pared intestinal. Presentamos caso de un varón de 82 años que acude a urgencias por un dolor súbito abdominal, difuso, con irritación peritoneal, leucocitosis con neutro...

Por y para en los manuales de ELE

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Sidoti, Rossana

2008-12-01

Full Text Available La oposición por / para es una de las cuestiones gramaticales que comportan mayor dificultad a la hora de acercarse al estudio del español como L2 sobre todo cuando remiten a conceptos lingüísticos difíciles de entender por no tener ésta referente alguno en el mundo extralingüístico. Si, por un lado, nos resulta fácil entender lo que tiene un referente en el mundo concreto; por otro, no podemos advertir el referente extralingüístico de preposiciones como por / para, si este no existe. Si las preposiciones son elementos abstractos, difíciles de aferrar de por sí, podemos sólo examinar los elementos que éstas ponen en relación y en qué contextos esta relación se determina. Para poder utilizar con precisión las dos preposiciones, es importante no reducirlas a una sola preposición como ocurre en otros idiomas, y sobre todo no relacionarlas sólo a los conceptos de causa y finalidad. Este trabajo se propone individualizar los manuales de español como lengua extranjera más utilizados en las universidades italianas para luego comparar las distintas fuentes de información sobre por / para y exponer comentarios, reflexiones y sugerencias sobre el tema con el fin de precisar en qué medida se puede mejorar lo que los manuales reducen o generalizan, puesto que para los estudiantes de ELE estos representan una herramienta valiosa a la que acudir.

A IDENTIFICAÇÃO DE TIPOS DE LIDERANÇA A PARTIR DE ARQUÉTIPOS

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Adriana Nunes Lacerda e Prestupa

2009-09-01

junguianos analisados por Moore e Gillette (1993 foram relacionados com características de líderes dentro do contexto organizacional. Desta forma foi possível apresentar uma tipologia rica e aplicável, onde o individuo pode se identificar e também entender o processo e a maturação das características dos arquétipos estudados para melhor desempenho dentro das organizações.

XPS and STM study of the growth and structure of passive films in high temperature water on a nickel-base alloy

Energy Technology Data Exchange (ETDEWEB)

Machet, A.; Galtayries, A.; Zanna, S.; Klein, L.; Maurice, V.; Jolivet, P.; Foucault, M.; Combrade, P.; Scott, P.; Marcus, P

2004-09-15

The early stages of passivation in high temperature water of a nickel-chromium-iron alloy (Alloy 600) have been investigated by X-ray Photoelectron Spectroscopy (XPS) and Scanning Tunneling Microscopy (STM). The samples (polycrystal Ni-16Cr-9Fe (wt. %) and single crystal Ni-17Cr-7Fe (1 1 1)) have been exposed for short time periods (0.4-8.2 min) to high temperature (325 deg. C) and high pressure water, under controlled hydrogen pressure, in a microautoclave designed to transfer the samples from and to the XPS spectrometer without air exposure. In the early stages of oxidation of the alloy (0.4-4 min), an ultra-thin oxide layer (about 1 nm) is formed, which consists of chromium oxide (Cr{sub 2}O{sub 3}), according to the Cr 2p{sub 3/2} core level spectrum. An outer layer of Cr(OH){sub 3} with a very small amount of Ni(OH){sub 2} is also revealed by the Cr 2p{sub 3/2}, Ni 2p{sub 3/2}, and O 1s core level spectra. At this early stage, there is a temporary blocking of the growth of Cr{sub 2}O{sub 3}. For longer exposures (4-8 min), the Cr{sub 2}O{sub 3} inner layer becomes thicker, at the expense of the outer Cr(OH){sub 3} layer. This implies the transport of Cr and Ni through the oxide layer, and release of Ni{sup 2+} in the solution. The structure of the ultra-thin oxide film formed on a single crystal Ni-17Cr-7Fe(1 1 1) alloy was analysed by STM in the constant current mode; STM images reveal that, in the early stages of oxidation, the oxide is crystalline, and the observed structure is consistent with the hexagonal structure of the oxygen sub-lattice in the basal plane (0 0 0 1) of {alpha}-Cr{sub 2}O{sub 3}.

Thorium effect on the oxidation of uranium: Photoelectron spectroscopy (XPS/UPS) and cyclic voltammetry (CV) investigation on (U{sub 1−x}Th{sub x})O{sub 2} (x = 0 to 1) thin films

Energy Technology Data Exchange (ETDEWEB)

Cakir, P., E-mail: pelincakir@outlook.com [European Commission, Joint Research Centre, P.O. Box 2340, D-76125, Karlsruhe (Germany); Department of Radiation Science and Technology, Delft University of Technology, Mekelweg 15, 2629, JB Delft (Netherlands); Eloirdi, R.; Huber, F. [European Commission, Joint Research Centre, P.O. Box 2340, D-76125, Karlsruhe (Germany); Konings, R.J.M. [European Commission, Joint Research Centre, P.O. Box 2340, D-76125, Karlsruhe (Germany); Department of Radiation Science and Technology, Delft University of Technology, Mekelweg 15, 2629, JB Delft (Netherlands); Gouder, T. [European Commission, Joint Research Centre, P.O. Box 2340, D-76125, Karlsruhe (Germany)

2017-01-30

Highlights: • XRD and XPS data of U{sub x}Th{sub 1-x}O{sub 2} films are in agreement with data obtained on bulk. • Oxygen affinity of thorium is much stronger than uranium. • Oxidation of uranium decreases as a function of thorium in the matrix. • XPS made pre and post CV shows thorium enrichment indicating a protective layer. • Higher initial uranium content is directly proportional to higher oxidation states. - Abstract: Thin films of U{sub 1−x}Th{sub x}O{sub 2} (x = 0 to 1) have been deposited via reactive DC sputter technique and characterized by X-ray/Ultra-violet Photoelectron Spectroscopy (XPS/UPS), X-ray Powder Diffractometer (XRD) and Cyclic Voltammetry (CV) in order to understand the effect of Thorium on the oxidation mechanism. During the deposition, the competition between uranium and thorium for oxidation showed that thorium has a much higher affinity for oxygen. Deposition conditions, time and temperature were also the subject of this study, to look at the homogeneity and the stability of the films. While core level and valence band spectra were not altered by the time of deposition, temperature was affecting the oxidation state of uranium and the valence band due to the mobility increase of oxygen through the film. X-ray diffraction patterns, core level spectra obtained for U{sub 1−x}Th{sub x}O{sub 2} versus the composition showed that lattice parameters follow the Vegard's law and together with the binding energies of U-4f and Th-4f are in good agreement with literature data obtained on bulk compounds. To study the effect of thorium on the oxidation of U{sub 1−x}Th{sub x}O{sub 2} films, we used CV experiments at neutral pH of a NaCl solution in contact with air. The results indicated that thorium has an effect on the uranium oxidation as demonstrated by the decrease of the current of the oxidation peak of uranium. XPS measurements made before and after the CV, showed a relative enrichment of thorium at the extent of uranium at

Efeito da saturação por bases sobre a atividade de fosfatases em um solo de tabuleiro costeiro cultivado com citros. I. Correlações entre a atividade enzimática e as diferentes características do solo alteradas pela calagem

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M. F. Fernandes

1998-09-01

Full Text Available Neste trabalho, utilizaram-se amostras de um Podzol cultivado com citros, na Estação Experimental de Umbaúba, Umbaúba-SE (Centro de Pesquisa Agropecuária dos Tabuleiros Costeiros-EMBRAPA, para avaliar a atividade de fosfatases ácidas e alcalinas em solo de tabuleiro costeiro submetido a diferentes porcentagens de saturação por base (32, 45, 68 e 76,6%, bem como as relações entre essas atividades e algumas características do solo. Respostas positivas ao incremento da saturação por bases foram observadas para pH, teor de matéria orgânica, fósforo disponível e atividade de fosfatases ácidas e alcalinas, em seus respectivos valores de pH ótimo de 6,5 e 11,0, ao passo que a biomassa microbiana não foi alterada significativamente por esse fator. Observou-se que a atividade da fosfatase ácida apresentou correlação significativa e positiva com a matéria orgânica e teores de cálcio e de magnésio trocáveis. A resposta das fosfatases alcalinas à saturação foi influenciada pelo pH, pela matéria orgânica, pelos teores de cálcio e de magnésio e pela biomassa microbiana do solo. Nenhuma das duas enzimas apresentou correlação com os teores de fósforo encontrados no solo analisado. No entanto, observou-se inibição da atividade das enzimas, quando a análise foi realizada em uma solução de reação com concentração de 124 ∝g mL-1 de P.

Evolução da mortalidade por câncer cérvico-uterino em Salvador - BA, 1979-1997 Evolution of the mortality for cervico-uterine cancer in Salvador - BA, 1979-1997

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Susanne Andrade Derossi

2000-12-01

Full Text Available O câncer cérvico-uterino, quando diagnosticado e tratado precocemente, constitui-se em uma causa de morte perfeitamente evitável. Entretanto, no Brasil, a mortalidade por esta causa ainda é elevada, persistindo como problema de saúde pública. O objetivo deste trabalho é descrever a evolução da mortalidade e estimar os anos potenciais e produtivos de vida perdidos por esta neoplasia, em Salvador-Bahia, entre 1979 e 1997. Trata-se de um estudo de agregados de série temporal, no qual foram considerados todos os óbitos de mulheres com idade igual ou superior a 20 anos, que tiveram como causa básica de morte o câncer de colo uterino e de porção não especificada do útero. Utilizou-se como fontes de dados o CD ROM: DATA SUS/ MS, o IBGE e a Secretaria de Saúde do Estado da Bahia/SESAB. Os indicadores empregados foram as taxas de mortalidade específicas por idade, brutas e padronizadas por idade. Houve um decréscimo de 50,6% na taxa padronizada de mortalidade por este tipo de câncer, no período analisado, cujos valores variaram de 17,6/100.000 mulheres em 1979 a 8,7 em 1997. Observou-se ainda que o risco de morte por esta causa cresce à medida que aumenta a idade e que a sua magnitude torna-se mais expressiva a partir de 40 anos. A variação da média de anos potenciais de vida perdidos por mulher foi de 15,5 no ano de 1986 a 20,4 em 1980. Os autores concluem que a mortalidade por câncer cérvico-uterino neste município ainda é alta e discutem os possíveis fatores determinantes da evolução desta mortalidade. Destacam a necessidade de ações efetivas na prevenção da morbi-mortalidade por esta causa.When early diagnosed and treated, cervical cancer is a perfectly avoidable cause of death. In Brazil, however, mortality from cervical cancer is still high and remains a public health problem. This study is aimed at both describing the evolution of such mortality and estimating the potential and productive years of life lost due

Padrão de refeições realizadas por adolescentes que frequentam escolas técnicas de São Paulo Estándar de comidas realizadas por adolescentes que frecuentan escuelas técnicas de São Paulo Pattern of meals eaten by adolescents from technical schools of São Paulo, SP, Brazil

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Erica Lie Araki

2011-06-01

Full Text Available OBJETIVO: Avaliar e caracterizar o consumo de refeições realizadas por adolescentes. MÉTODOS: Estudo transversal com 71 adolescentes do ensino médio de escolas técnicas de São Paulo. Foi utilizado um questionário que avalia atitudes alimentares de ado-lescentes. As variáveis estudadas foram: frequência, local, com quem realiza as refeições e substituição de refeições por lanches. Os dados foram analisados descritivamente e o teste do qui-quadrado comparou as variáveis segundo gênero, considerando nível de significância de 5%. RESULTADOS: Do total, 58% eram do gênero feminino. A maioria relatou realizar as principais refeições em casa (88% café da manhã, 91% almoço e 96% jantar. Quanto à frequência do consumo, 49% realizavam todos os dias o café da manhã, 65% o almoço e 51% o jantar. Os adolescentes consumiam tanto o café da manhã (48% quanto o almoço (39% sozinhos, enquanto o jantar (77% era realizado com os pais, havendo, para o jantar, diferença entre gêneros (p=0,022. Observou-se que 29% substituíam o almoço por lanches e, destes, 17% o faziam uma a duas vezes por semana. No jantar, uma porcentagem maior de adolescentes o subs-tituía por lanche (62%, sendo a frequência de substituição de uma a duas vezes por semana para 42% deles. CONCLUSÕES: Apesar de os adolescentes realizarem as re-feições em casa, as mesmas não são feitas diariamente nem acompanhadas pelos pais.OBJETIVO: Evaluar y caracterizar el consumo de comidas realizadas por adolescentes. MÉTODOS: Estudio transversal con 71 adolescentes de la secundaria de escuelas técnicas de São Paulo (Brasil, prove-nientes de un estudio transversal. Se utilizó un cuestionario que evalúa actitudes alimentares de adolescentes. Las variables estudiadas fueron: frecuencia, local, con quién realiza las co-midas y la sustitución de comidas por meriendas. Los datos fueron analizados descriptivamente y se utilizó la prueba del Chi-Cuadrado para

Effect of nitrogen plasma afterglow on the surface charge effect resulted during XPS surface analysis of amorphous carbon nitride thin films

Science.gov (United States)

Kayed, Kamal

2018-06-01

The aim of this paper is to investigate the relationship between the micro structure and the surface charge effect resulted during XPS surface analysis of amorphous carbon nitride thin films prepared by laser ablation method. The study results show that the charge effect coefficient (E) is not just a correction factor. We found that the changes in this coefficient value due to incorporation of nitrogen atoms into the carbon network are related to the spatial configurations of the sp2 bonded carbon atoms, order degree and sp2 clusters size. In addition, results show that the curve E vs. C(sp3)-N is a characteristic curve of the micro structure. This means that using this curve makes it easy to sorting the samples according to the micro structure (hexagonal rings or chains).

Pronóstico de la diarrea por rotavirus

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Mota-Hernández Felipe

2001-01-01

Full Text Available Objetivo. Comparar la gravedad de la diarrea por rotavirus (RV y por no rotavirus. Material y métodos. Estudio transversal en 520 lactantes con diarrea aguda, efectuado entre octubre de 1994 y marzo de 1995 en siete centros del primer nivel de atención en cinco estados de México. El diagnóstico de RV se realizó con ensayo inmunoenzimático o por electroforesis. El análisis se hizo a través de medidas de tendencia central. Los resultados se presentan como promedio y desviación estándar o mediana o variación. Resultados. Se aisló RV en 264 lactantes (50.7% con predominio en varones de 6 meses a un año. Las manifestaciones clínicas fueron significativamente diferentes entre el grupo rotavirus positivo y el grupo rotavirus negativo en mediana de evacuaciones por 24 horas, frecuencia de vómitos, temperatura > 38° C, deshidratación y calificación de gravedad, respectivamente. Conclusiones. Estos resultados mostraron peor pronóstico por mayor gravedad de la diarrea por RV en lactantes, con relación a otra etiología. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html

ANÁLISE DE UMA ORGANIZAÇÃO FAMILIAR À LUZ DO MODELO MULTIDIMENSIONAL-REFLEXIVO

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Isabela Neves Ferraz

2015-10-01

Full Text Available O principal objetivo deste trabalho consiste em analisar, a partir da realização de um estudo de caso, uma organização familiar, tendo como referência o Modelo Multidimensional-Reflexivo de Alves (2003. Todos os característicos retratados no presente artigo, obtidos através da pesquisa documental, entrevistas e observação não-participante, e analisados por meio da técnica de análise de conteúdo, permitiram, como principal achado, o enquadramento da empresa familiar analisada como uma organização, de fato, equiparativo-adaptadora, à luz do modelo formulado por Alves (2003.

Miasis cutanea por cordylobia anthropophaga

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Alkorta Gurrutxaga Miriam

2001-01-01

Full Text Available El incremento progresivo en el número de personas que viajan a países tropicales ha hecho que las enfermedades importadas adquieran una relevancia cada vez mayor. Las miasis (o infestaciones por larvas de moscas cutáneas se encuentran entre este tipo de enfermedades siendo especialmente frecuentes en países tropicales. A propósito de la observación de un caso de miasis cutánea masiva por Cordylobia antropophaga, que ocurrió en una mujer de 34 años de edad al volver de un viaje a Senegal, se ha efectuado una revisión de los casos de miasis cutáneas forunculoides importadas publicados en España, así como de la biología, patología, tratamiento y prevención de la miasis humana por Cordylobia anthropophaga. El caso referido, se caracterizó por la infestación con un número inusualmente elevado de larvas, no sospechándose su etiología hasta la fase final de la enfermedad. La emergencia continuada de larvas (se recogieron 91 generó en la paciente un estado de ansiedad importante. Finalmente, la eliminación de las larvas provocó una rápida mejoría de la paciente. Aunque los casos de miasis cutánea no tienen la gravedad de otras enfermedades importadas, su conocimiento es necesario desde el punto de vista preventivo, diagnóstico y terapeútico. Es importante proceder a la identificación morfológica de las larvas diferenciándolas de otro tipo de miasis con implicaciones terapéuticas diferentes.

Associação entre violência por parceiro íntimo contra a mulher e infecção por HIV Asociación entre violencia contra la mujer por pareja íntima e infección por VIH Association between intimate partner violence against women and HIV infection

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Claudia Barros

2011-04-01

Full Text Available OBJETIVO: Analisar a associação entre a violência por parceiro íntimo contra mulheres e a infecção ou suspeita de infecção pelo vírus da imunodeficiência humana (HIV. MÉTODOS: Estudo transversal com base em dados de questionários aplicados face-a-face e de prontuários médicos de 2.780 mulheres de 15 a 49 anos, atendidas em unidades do sistema único de saúde da Grande São Paulo, SP, em 2001-2002. As mulheres foram categorizadas em: usuárias em tratamento por serem "soropositivas para o HIV", com "suspeita de HIV" e aquelas que procuraram os serviços por outros motivos. A violência por parceiro íntimo contra mulheres na vida foi categorizada por gravidade e recorrência dos episódios de violência. A associação com o desfecho foi testada pelo modelo de Poisson com variância robusta e ajustada por variáveis sociodemográficas, sexuais e reprodutivas. RESULTADOS: A prevalência de violência foi de 59,8%. Sofrer violência reiterada e grave apresentou maior associação de infecção confirmada pelo HIV (RP = 1,91. A violência independente da gravidade e da recorrência dos episódios apresentou maior associação para a suspeita de infecção por HIV (RP = 1,29. CONCLUSÕES: A violência por parceiro íntimo contra mulheres tem papel relevante nas situações de suspeita e confirmação da infecção pelo HIV, sendo essencial incluir sua detecção, controle e prevenção como parte da atenção integral à saúde das mulheres.OBJETIVO: Analizar la asociación entre la violencia contra mujeres por pareja íntima y la infección o sospecha de infección por el virus de inmunodeficiencia humana (VIH. MÉTODOS: Estudio transversal con base en datos de cuestionarios aplicados cara-a cara y de prontuarios médicos de 2.780 mujeres de 15 a 49 años, atendidas en unidades del sistema único de salud de la Gran Sao Paulo, Sureste de Brasil, en 2001-2002. Las mujeres fueron categorizadas en: usuarias en tratamiento por ser

SEM, Scanning Auger and XPS characterization of chemically pretreated Ti surfaces intended for biomedical applications

Energy Technology Data Exchange (ETDEWEB)

Pisarek, M. [Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw (Poland); Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland)], E-mail: marcinp@ichf.edu.pl; Lewandowska, M. [Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw (Poland); Roguska, A. [Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw (Poland); Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland); Kurzydlowski, K.J. [Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw (Poland); Janik-Czachor, M. [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw (Poland)

2007-07-15

Titanium is known as a biocompatible metal characterized by biological and corrosion immunity and good mechanical properties, including a high fracture toughness. In a variety of environments, this metal undergoes 'natural' oxidation which determine its resistance to corrosion. It can also be exposed to chemical treatments in acidic or alkaline solutions which 'enforces' chemical and morphological changes of Ti surface. Those methods, if well controlled, may increase the effective Ti surface area, making it more biocompatible. However, the morphological and chemical factors responsible for their interactions with biological cells are still not well known. The aim of this work was to compare surface chemical and morphological changes introduced by commonly used aqueous NaOH pretreatment with those occurring in a new 'piranha' acidic solution. Particular attention was paid to possible changes which may be decisive for the biocompatibility of the Ti-elements subjected to these surface modifications. Surface analytical techniques such as Auger electron spectroscopy (AES) or X-ray photoelectron spectroscopy (XPS) combined with Ar{sup +} ion sputtering allowed us to investigate in detail the chemical composition of Ti oxide layers. SEM examinations provided morphological characterization of the surface of Ti samples. The results revealed large difference in morphology of Ti surfaces pretreated with different procedures whereas only minor difference in the chemistry of the surfaces were detected.

XPS analysis of the effect of fillers on PTFE transfer film development in sliding contacts

Science.gov (United States)

Blanchet, T. A.; Kennedy, F. E.; Jayne, D. T.

1993-01-01

The development of transfer films atop steel counterfaces in contact with unfilled and bronze-filled PTFE has been studied using X-ray photoelectron spectroscopy. The sliding apparatus was contained within the vacuum of the analytical system, so the effects of the native oxide, hydrocarbon, and adsorbed gaseous surface layers of the steel upon the PTFE transfer behavior could be studied in situ. For both the filled and the unfilled PTFE, cleaner surfaces promoted greater amounts of transfer. Metal fluorides, which formed at the transfer film/counterface interface, were found solely in cases where the native oxide had been removed to expose the metallic surface prior to sliding. These fluorides also were found at clean metal/PTFE interfaces formed in the absence of frictional contact. A fraction of these fluorides resulted from irradiation damage inherent in XPS analysis. PTFE transfer films were found to build up with repeated sliding passes, by a process in which strands of transfer filled in the remaining counterface area. Under these reported test conditions, the transfer process is not expected to continue atop previously deposited transfer films. The bronze-filled composite generated greater amounts of transfer than the unfilled PTFE. The results are discussed relative to the observed increase in wear resistance imparted to PTFE by a broad range of inorganic fillers.