3,298 research outputs found
Avaliação do desempenho dos componentes de cartão em embalagens
No full textMestrado em Engenharia QuímicaEsta dissertação tem como objetivo avaliar a influência de matérias-primas pré-selecionadas e das condições processuais utilizadas no fabrico de embalagens de cartão da Empresa Cartig, Cartão e Artigos para Embalagem, Lda. Propõe-se neste trabalho, melhorar a aparência do produto final, tendo em consideração a qualidade e a fiabilidade dos produtos, face aos seus clientes.
Inicialmente, determinou-se a composição química e morfológica de três cartolinas distintas pré-selecionadas, com gramagens diferentes, Barcelona 250 g∙m-2, Brasil 250 g∙m-2 e Brasil 225 g∙m-2. Estas cartolinas fazem parte da embalagem final de cartão.
Através da técnica de medição do ângulo de contacto, comparou-se o desempenho das cartolinas referidas anteriormente, a diferentes condições de humidade (40% e 80%) e temperatura (≈20°C e 35°C), para avaliar as condições processuais no fabrico das embalagens. A partir desta mesma técnica, estudou-se o desempenho de contracolagem e colagem das colas frias, Euroflex 5119 e INDU C 2065, usadas no processo contracolagem de cartolinas, e Aquence FB 7371 e Aquence FB 7362 utilizadas no processo colagem de embalagens da empresa.
Ainda neste trabalho, determinaram-se as propriedades e as características das colas frias utilizadas no processo de colagem e contracolagem, através do pH, teor de sólidos, viscosidade, assim como, das técnicas FTIR-ATR e TGA.
A análise térmica DCS foi aplicada apenas à cola quente Technomelt Supra Ultra GA 3920 usada na colagem das embalagens.
Estimaram-se as propriedades físico-mecânicas das cartolinas pré-selecionadas que são fundamentais para a caracterização da resistência e qualidade do material. O tempo de secagem ótimo das colas utilizadas no processo de colagem da empresa foi determinado através de ensaios fabris, com um estudo da humidade relativa ao longo do tempo das cartolinas China 200 g∙m-2 e Avelino Bastos 225 g∙m-2. O grau de adesividade foi determinado através do Teste de Adesividade (PAT) a todas as colas e cartolinas envolvidas no trabalho.
Verificou-se que as condições fabris (temperatura e humidade) influenciam bastante os resultados de contracolagem, especialmente a baixas temperaturas. Nesta dissertação conclui-se também que, a cola mais favorável para o processo de colagem da empresa é a cola Aquence FB 7371 e, no processo de contracolagem é a Euroflex 5119, sendo que estas impregnam-se pouco nas cartolinas e canelados em condições de temperaturas elevadas e humidades reduzidas (35ºC e 40%), evitando prejudicar a aparência da embalagem. Por último, face às três cartolinas pré-selecionadas, a Brasil 250 g∙m-2 é a cartolina com melhores características, propriedades de resistência, qualidade e relação cola/adesividade. Esta em condições de baixa humidade e temperaturas elevadas apresenta elevados ângulos de contacto com as colas estudadas, mantendo uma adesividade elevada e uma boa performance.This dissertation aims to evaluate the influence of pre-selected raw materials and the procedural conditions used in the manufacture of carton packs of the company Cartig, Cartão e Artigos para Embalagem, Lda. The objective of this work was to improve the appearance of the final product, considering the quality and reliability of the products, for the customers.
Initially, the chemical and morphological composition of three pre-selected different cardboards with different weights, namely, Barcelona 250 g∙m-2, Brazil 250 g∙m-2 and Brazil 225 g∙m-2, were determined. These cartons are part of the final carton package.
Through the contact angle measurement technique, the performance of the above-mentioned cardboards was compared to different humidity conditions (40% and 80%) and temperature (≈20 ° C and 35 ° C) to evaluate the procedural conditions in the manufacturing of packages. Using the same technique, the glue performance and gluing performance of the cold glues, Euroflex 5119 and INDU C 2065, used in the backed gluing process of cardboards, and Aquence FB 7371 and Aquence FB 7362 used in the gluing process of the company packaging were studied.
Also in this work, the properties and characteristics of cold glues used in the gluing and backed gluing processes were determined through pH, solids content, viscosity, as well as FTIR-ATR and TGA techniques. Thermal DCS analysis was applied only to the hot glue Technomelt Supra Ultra GA 3920 used in the gluing of packages.
The physical-mechanical properties of the pre-selected cardboards were determined, being these fundamental for the characterization of the strength and quality of the material. The optimal drying time of the glue used in the gluing process of the company was determined by manufacturing tests, the study of moisture over time, to the cardboards China 200 g∙m-2 and Avelino Bastos 225 g∙m-2. The degree of adhesiveness was determined through the Pin Adhesion Test (PAT) to all glues and cardboards involved in the work.
It has been found that the manufacturing conditions (temperature and humidity) greatly influence the results of the backed gluing, especially at low temperatures. In this dissertation, it is also concluded that the glue most favorable to the gluing process of the company is the glue Aquence FB 7371 and, in the process of back gluing is the Euroflex 5119, which impregnates less in the cardboards on conditions of high temperatures and reduced humidity (35ºC and 40%), avoiding to spoil the appearance of the packaging. Finally, comparing the three pre-selected cardboards, Brazil 250 g∙m-2 is the cardboard with the best characteristics, resistance properties, quality and glue/adhesion ratio. It is in conditions of low humidity and high temperatures that it has high angles of contact with the glues studied, maintaining a high adhesiveness and good performance
Parents studying medicine : the dichotomy of studying with a family
No full textIntroduction: In this article the personal study and life situation of parents who are also medical students at the Medical School of the Goethe University Frankfurt am Main is discussed. There is a special focus on the topics "studying with children" and "family-friendly university", which have been present in discussions about university development and in the daily life of academics, especially during the last decade. The workgroup "Individual Student Services" at the medical faculty at the Goethe University tries to meet the necessities of the individual study courses and to support the study success with a new counselling and student service concept.
Methods: The experience of parents studying medicine was recorded in semi-structured interviews (Date: April 2010), which were held as part of the sponsored pilot project on part-time medical studies ("Pilot Project Part-time Medical Studies"). Additionally, study results from the Medical School of the Goethe University Frankfurt am Main were integrated as well as a literature analysis.
Results: It was found that the teaching demands and support services, which have been suggested and needed for years now, have been partially implemented and are without sufficient support at the faculty level to date. Thus the current situation of medical students with children is still difficult and seems a big challenge for everyone involved.
Solution: As part of the "Individual Student Services" a new pilot project on part-time medical studies was established in November 2009. Only the use of new, unconventional and innovative ideas allows universities to adequately support the changing and heterogeneous student population and support them to successfully completing their medical studies
Manutenção do teor de carbono na sinterização por plasma Ar-H2-CH4 de injetados em aço ao carbono baixa liga /
No full textDissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Neste trabalho foi estudada a manutenção do teor de carbono na sinterização por plasma de injetados de aço ao carbono baixa liga, utilizando-se uma mistura gasosa de Ar-H2-CH4. Na sinterização de um aço ao carbono a mistura Ar-H2 favorece a descarbonetação. Por isso, foi necessária a utilização de um gás portador de carbono, a fim de estabelecer no plasma um potencial efetivo de carbono que tornasse nulo o fluxo líquido deste elemento entre o material e o volume gasoso. O plasma foi caracterizado através de medidas elétricas e por espectrosccopia ótica de emissão. A seguir, efetuaram-se sinterizações a 1150°C/60min, com diferentes teores de CH4 na mistura gasosa Ar-20%H2. Análises de microssonda WDS, ensaios metalográficos e de microdureza Vickers, permitiram obter uma relação entre a quantidade de carbono total em amostras de 1,35 mm de espessura, de um aço ao carbono baixa liga, foram relacionadas com o potencial efetivo de carbono do plasma em função da quantidade de metano injetado na mistura Ar-20%H2
Interpretations and implications of the top quark rapidity asymmetries A(FB)(t) and A(FB)(l)
No full textForward-backward asymmetries A(FB)(t) and A(FB)(l) are observed in the top-quark t rapidity distribution and in the rapidity distribution of charged leptons l from top-quark decay at the Tevatron proton-antiproton collider, and a charge asymmetry A(C) is seen in proton-proton collisions at the Large Hadron Collider (LHC). In this paper, we update our previous studies of the Tevatron asymmetries using the most recent data. We provide expectations for AC at the LHC based first on simple extrapolations from the Tevatron, and second based on new physics models that can explain the Tevatron asymmetries. We examine the relationship of the two asymmetries A(FB)(t) and A(FB)(l). We show their connection through the (V - A) spin correlation between the charged lepton and the top quark with different polarization states. We show that the ratio of the two asymmetries provides independent insight into the physics interpretation of the top-quark asymmetry. We emphasize the value of the measurement of both asymmetries, and we conclude that a model which produces more right-handed than left-handed top quarks is suggested by the present Tevatron data.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000322145600004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Astronomy & AstrophysicsPhysics, Particles & FieldsSCI(E)7ARTICLE1null8
Top Quark Production Asymmetries A(FB)(t) and A(FB)(l)
No full textA large forward-backward asymmetry is seen in both the top quark rapidity distribution A(FB)(t) and in the rapidity distribution of charged leptons A(FB)(l) from top quarks produced at the Tevatron. We study the kinematic and dynamic aspects of the relationship of the two observables arising from the spin correlation between the charged lepton and the top quark with different polarization states. We emphasize the value of both measurements, and we conclude that a new physics model which produces more right-handed than left-handed top quarks is favored by the present data.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000300247100002&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, MultidisciplinarySCI(E)EI20ARTICLE6null10
Depolarization and decreased surface expression of K+ channels contribute to NSAID-inhibition of intestinal restitution
No full textNon-steroidal anti-inflammatory drugs (NSAIDs) contribute to gastrointestinal ulcer formation by inhibiting epithelial cell migration and mucosal restitution; however, the drug-affected signaling pathways are poorly defined. We investigated whether NSAID inhibition of intestinal epithelial migration is associated with depletion of intracellular polyamines, depolarization of membrane potential (Em) and altered surface expression of K+ channels. Epithelial cell migration in response to the wounding of confluent IEC-6 and IEC-Cdx2 monolayers was reduced by indomethacin (100μM), phenylbutazone (100μM) and NS-398 (100μM) but not by SC-560 (1μM). NSAID-inhibition of intestinal cell migration was not associated with depletion of intracellular polyamines. Treatment of IEC-6 and IEC-Cdx2 cells with indomethacin, phenylbutazone and NS-398 induced significant depolarization of Em, whereas treatment with SC-560 had no effect on Em. The Em of IEC-Cdx2 cells was: −38.5±1.8mV under control conditions; −35.9±1.6mV after treatment with SC-560; −18.8±1.2mV after treatment with indomethacin; and −23.7±1.4mV after treatment with NS-398. Whereas SC-560 had no significant effects on the total cellular expression of Kv1.4 channel protein, indomethacin and NS-398 decreased not only the total cellular expression of Kv1.4, but also the cell surface expression of both Kv1.4 and Kv1.6 channel subunits in IEC-Cdx2. Both Kv1.4 and Kv1.6 channel proteins were immunoprecipitated by Kv1.4 antibody from IEC-Cdx2 lysates, indicating that these subunits co-assemble to form heteromeric Kv channels. These results suggest that NSAID inhibition of epithelial cell migration is independent of polyamine-depletion, and is associated with depolarization of Em and decreased surface expression of heteromeric Kv1 channels.ID: S0006295207001931; M3: Article; Accession Number: S0006295207001931; Author: L.C. Freeman (b); Author: D.F. Narvaez (a); Author: A. McCoy (a); Author: F.B. von Stein (c); Author: S. Young (b); Author: K. Silver (a); Author: S. Ganta (b); Author: D. Koch (b); Author: R. Hunter (b); Author: R.F. Gilmour (c); Author: J.D. Lillich (a, ⁎); Affiliation: Department of Clinical Sciences, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, United States; Keyword: Non-steroidal anti-inflammatory drugs; Keyword: Intestinal epithelial cells; Keyword: Membrane potential; Keyword: Potassium channels; Number of Pages: 12; Language: English;Source type: Electronic(1)http://search.ebscohost.com/login.aspx?direct=true&db=edselp&AN=S0006295207001931&site=eds-live&scope=sit
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
Retelling racialized violence, remaking white innocence: the politics of interlocking oppressions in transgender day of remembrance
No full textTransgender Day of Remembrance has become a significant political event among those resisting violence against gender-variant persons. Commemorated in more than 250 locations worldwide, this day honors individuals who were killed due to anti-transgender hatred or prejudice. However, by focusing on transphobia as the definitive cause of violence, this ritual potentially obscures the ways in which hierarchies of race, class, and sexuality constitute such acts. Taking the Transgender Day of Remembrance/Remembering Our Dead project as a case study for considering the politics of memorialization, as well as tracing the narrative history of the Fred F. C. Martinez murder case in Colorado, the author argues that deracialized accounts of violence produce seemingly innocent White witnesses who can consume these spectacles of domination without confronting their own complicity in such acts. The author suggests that remembrance practices require critical rethinking if we are to confront violence in more effective ways. Description from publisher's site: http://caliber.ucpress.net/doi/abs/10.1525/srsp.2008.5.1.2
Freeze-bond strength: Analysis of experiments and FE modeling of a shear test on freeze bonds
No full textThe objective of this study was to contribute to the knowledge on ice-ridges structures interactions. This work is a follow-up of previous research on simulations of ice-structure interaction using finite element method (Gürtner, 2009b; Konuk, et al., 2009a,b) and a preliminary study of freeze-bond (FB) shear strength (Repetto-Llamazares, et al., 2009b). The presented data should be regarded as illustrative rather than exhaustive. Many important aspects of ice-ridges structures interactions have not been addressed in this thesis. An analysis of experiments with FBs was performed, and a finite element model was built in order to simulate these experiments. Within the framework of the classical theory of elasticity, the numerical model incorporates a cohesive model in order to simulate ice fracture along the FB during shear test. The cohesive behavior of the FB was described by the bilinear traction-separation law. The approach of Camanho and Davila (2002) was applied in order to calculate stresses in the FB under mixed-mode loading conditions. A 6-node cohesive finite element was used for implementation of assumed behavior of the FB. Information obtained via detailed analysis of the FB shear strength experiments and via their numerical simulation can be used for a better understanding of FB failure processes and for a numerical modeling of ice-ridges. The results of numerical simulation confirmed that the finite element model could reproduce phenomena commonly observed in actual shear tests of FBs, including the shear strength hardening and partly softening behavior. The peak load in simulations was completely determined by the maximum traction strength and the initial part of a traction-separation law. This study also showed that from the conducted experiments intended to study FB strength in model ice, it is also possible to study ice fracture processes as well as post-failure behavior. By improving the experimental procedure as described in Repetto-Llamazares, et al. (2009b) it will be possible to study not only FB shear strength but also the frictional behavior of ice after the FB failure. By video monitoring of the crack initiation and growth it will be possible to study a fracture process inside the FB. This work is of appeal to different scientists actively participating in investigations in, and possibly also on the standardization of methods for, measuring strength of freeze-bonds in order to improve existing analytical and numerical models, which are used nowadays for calculation of loads for scenarios of ice-ridges interactions with structures.CoMEM - Coastal and Marine Engineering and ManagementHydraulic EngineeringCivil Engineering and Geoscience
Search for Diphoton Events with Large Missing Transverse Momentum in 1 fb^-1 of 7 TeV Proton-Proton Collision Data with the ATLAS Detector
No full textSee paper for full list of authors - 8 pages plus author list (21 pages total), 6 figures, 2 tables, submitted to Physics Letters BA search for diphoton events with large missing transverse momentum has been performed using 1.07 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded with the ATLAS detector. No excess of events was observed above the Standard Model prediction and 95% Confidence Level (CL) upper limits are set on the production cross section for new physics: sigma < (22-129) fb in the context of a generalised model of gauge-mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, sigma < (27-91) fb in the context of a minimal model of gauge-mediated supersymmetry breaking (SPS8) and (15-27) fb in the context of a specific model with one universal extra dimension (UED). A 95% CL lower limit of 805 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass. Lower limits of 145 TeV and 1.23 TeV are set on the SPS8 breaking scale Lambda and on the UED compactification scale 1/R, respectively. These limits provide the most stringent tests of these models to date
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