Dissertations / Theses on the topic 'Ptai'
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Ebner, Fabian [Verfasser], and Lutz [Akademischer Betreuer] Greb. "Planare Silizium(IV)-Verbindungen (ptSi) und planare Aluminate (ptAl-). Von strukturellen Kuriositäten hin zu anwendbaren Reaktivitäten / Fabian Ebner ; Betreuer: Lutz Greb." Heidelberg : Universitätsbibliothek Heidelberg, 2021. http://d-nb.info/122853988X/34.
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Solt, Katalin. "Ultraviolet sensitive PtSi-n-Si photodiodes with sputtered PtSi Schottky contacts /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10917.
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Bengtsson, Christofer, and Kristoffer Madsen. "PTAG - aktiv RFID-tag med GPS." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1648.
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Free2Move AB is developing products for the market within wireless communication
and identification, among those active RFID-tags. The company had an idea about
providing one of their active RFID tags with a GPS receiver and transmit positions via
an existing RFID protocol. Desire from the company was also the possibility to log
positions and measure temperature. The finished prototype should also be able to be
activated by movement. The company had proposal about components that were to be
used in the project. A large part of the work was to understand how these worked and
how to combine them to fulfill the requirements established in agreement with
supervisor at Free2Move. A PIC microcontroller was used in the design of the prototype
and software implemented for communication with GPS, RFID tag and other
components. The result was a working prototype where an existing RFID tag was
integrated in the same printed circuit board layout as the GPS receiver and other
components that were used in the project.
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Lu, Kuo-Chang. "Nano-silicide formation through point contact reaction, NiSi/Si/NiSi and PtSi/Si/PtSi nanowire heterostructures for nanodevices." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1779690511&sid=4&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Maystre, Charles. "Les grands prêtres de Ptah de Memphis /." Freiburg (Schweiz) : Göttingen : Universitätsverl. ; Vandenhoek & Ruprecht, 1992. http://catalogue.bnf.fr/ark:/12148/cb36664259n.
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Golod, Taras. "Hybrid superconductor junctions with diluted PtNi ferromagnetic interlayer." Licentiate thesis, Stockholms universitet, Fysikum, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-54847.
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This thesis describes experimental investigation of thin films made of diluted Pt 1-x Ni x ferromagnet alloy and Nb-Pt 1-x -Nb Josephson junctions. Such Hybrid Superconductor-Ferromagnet (S-F) Structures are of significant interest because of the new physics involved and possible applications in low temperature and spintronic devices. In many cases, such devices require components with small monodomain ferromagnetic layers, which requires development of specific nano-fabrication techniques. Pt 1-x Ni x alloy is used as the ferromagnet layer due to very good solubility of the two components which results in homogeneous diluted ferromagnet. Systematic analysis of both chemical composition, and ferromagnetic properties of Pt 1-x Ni x thin films for Ni concentrations ranging between 0 and ~70 at.% is performed. The energy-dispersive X-ray spectroscopy (EDS) technique is employed to study chemical composition of Pt 1-x Ni x thin films. To eliminate possible errors during EDS characterization, EDS is used with different electron beam energies, different electron beam incident angles and on the free standing Pt 0.59 Ni 0.41 flakes. Ferromagnetic properties of Pt 1-x Ni x thin films are analyzed by studying the anomalous Hall effect. The Curie temperature of Pt 1-x Ni x films decreases in a non-linear manner with the Ni concentration and has the onset at ~27 at.% of Ni. It is observed that the critical concentration of Ni is lower and the Curie temperature is higher than it had been observed early for the bulk PtNi alloys. The 3D Focused ion Beam Nanosculpturing is used to fabricate nanoscale S-F-S Josephson junctions providing the uniform, monodomain structure of the ferromagnet layer within the junction. The detailed studies of S-F-S Josephson junctions are carried out depending on the size of junction, thickness and composition of the ferromagnet layer. The obtained Fraunhofer modulation of the critical current as a function of in-plane magnetic field serves as evidence for uniformity of the junction properties and monodomain structure of ferromagnet layer. The junction critical current density decreases in spin glass state with increasing Ni concentration. In the ferromagnetic state the maximum current density of the junction starts to increase. The latter is attributed to switching into the pi state as a function of Ni concentration. Simultaneously it is observed that the critical current can completely disappear presumably as the result of stray fields from the F layer in contact leads. The Josephson junction is used as a phase sensitive detector for analysis of vortex states in mesoscopic superconductors. By changing the bias current at constant magnetic field the vortices can be manipulated and the system can be switched between two consecutive vortex states. A mesoscopic superconductor can thus act as a memory cell in which the junction is used both for reading and writing information (vortex).
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West, Nathan M. Templeton J. L. "Bond activation by nitrogen ligated PtII/PtIV complexes." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2307.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Jun. 26, 2009). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry.
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Scheuermann, Margaret L. "Reactivity of PtII "Pincer" Complexes with Carbon Monoxide." Scholarship @ Claremont, 2008. https://scholarship.claremont.edu/scripps_theses/6.
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ABSTRACT Upon addition of carbon monoxide (CO) to a solution of (k-N, C, N-2, 6-bis(diethylaminomethyl)-phenyl)methyl platinum(II),[NCN]PtMe,(1), a ligand arm is displaced to form [SP-4-2] ((k-N,C-2,6-bis(diethylaminomethyl)-phenyl) carbonmethyl platinum(II), N[CN]Pt(CO)(Me),(2). Addition of CO to a THF solution of 2 results in the formation of [SP-4-3]((k-N,C-2,6-bis(diethylaminomethyl)-phenyl)acylcarbonyl platinum(II),N[CN]pt(Ac)(CO),(3). In THF ,2 partially isomerizes in the presence of CO to form [SP-4-4]((k-N,C-2,6-bis(diethylaminomethyl)-phenyl)carbonylmethyl platinum(II), N[CN]Pt(Me)(CO).(2’).in equilibrium with 2(K=ca.2 at 100 degree celcius). In the absence of CO, only trace isomerization was observed. Thermolysis of 3 results in the formation of 2 and 2’ , while a reaction of 3 with trimethylamine N-oxide results exclusively in the formation of 2. Both three and five-coordinate intermediates have been shown to be accessible ,leading to two proposed mechanisms for the thermolysis of 3 and the microscopic reverse of this reaction.
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Straukaitė, Erika. "UAB "PTA Group" vartotojų lojalumo tyrimas." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100903_001321-49819.
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SANTRAUKA
Bakalauro baigiamajame darbe pateikiama užsienio ir lietuvių autorių suformuotos vartotojų lojalumo sampratos ir esmė, atskleisti ir analizuojami vartotojų lojalumą formuojantys veiksniai, lojalių klientų nauda įmonei, nagrinėjami lojalumo tipai ir lojalumo matavimo metodai. Remiantis išanalizuota literatūra lojalumo formavimo aspektu ir naudojantis lojalumo ekspertų F. Reicheldo bei J. J. Ellingo ir S. Jorgenseno lojalumo matavimo metodais atlikta UAB „PTA Group“ vartotojų lojalumo analizė.
Šio bakalauro sudedamosios dalys: 1. vartotojų lojalumo sampratų, formavimo, naudos ir matavimo analizės teoriniu aspektu; 2. UAB „PTA Group“ vartotojų lojalumo Šiaulių mieste tyrimo analizė.
Tyrime dalyvavo 100 Šiaulių miesto moterų, kurios žino ir bent kartą buvo apsilankiusios, pirko PTA rūbų parduotuvėje. Atlikus ne tik esamų ir pastovių, bet ir potencialiai lojalių PTA klienčių apklausą, nustatyta, ne tik kokie veiksniai labiausiai įtakoja prisirišimą ir teigiamą požiūrį PTA atžvilgiu bet atskleistos ir nelojalumo, nepirkimo PTA priežastys bei kas paskatintų neutralių ir potencialiai lojalių vartotojų grupes pirkti PTA. Atsižveldama į atitinkamą lojalumo lygį pasiekusius vartotojus, PTA įmonė gali kurti marketingo strategijas, teikti skirtingus pasiūlymus ir skatinimo priemones. Šio tyrimo duomenys gali būti naudingi tobulinant savo įmonės marketingo strategiją, plečiant aptarnaujamą segmentą, atsižvelgiant į klientų nuomones, poreikius ir į daugumą, kuri neša įmonei... [toliau žr. visą tekstą]SUMMARY In this final work of Bachelor studies are submitted the concept and essence in customer loyalty structured by foreign and Lithuanian authors, analyzing the factors, witch form customer loyalty, benefits of the company of loyal customers, examined the types of loyalty and loyalty measurement methods. According to literature reviewed in the formation of loyalty and respect through loyalty expert F. Reicheldo, J. J. Elling, S. Jorgensen loyalty measurement approaches was taken UAB “PTA Group's” customer loyalty analyze. Component parts of final work of Bachelor studies are: 1. customer loyalty concepts, formation, value and measurement analysis of the theoretical aspect; 2. customer loyalty study analysis on UAB “PTA Group” in the city of Siauliai. The study included 100 women in the city of Siauliai, which know and have been visited at least once or bought in PTA clothing shop. After not only current and stable, but potentially loyal customers survey done, was found not only what factors most affect the attachment and a positive attitude to PTA but also was founded the reasons of disloyalty and what neutral and potentially loyal consumers groups lead to buy PTA. Considering to permitted level of loyal consumers, PTA can create marketing strategies to differentiate their offerings and incentives. These studies may be useful in improving PTA company's marketing strategy, expanding the catchment segment according to customer opinions and needs and of the majority of the... [to full text]
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Werry, Arnaud. "Développement de matériaux multi échelles anti usure et anticorrosion pour remplacement des stellites en milieu nucléaire." Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0111/document.
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Le remplacement des Stellites, un superalliage base cobalt, en milieu nucléaire dans certaines parties du réacteur en milieu primaire a été étudié depuis les années soixante. Plusieurs nuances de revêtements base Fer et Nickel, sans ou avec très peu de cobalt, ont été développées dans ce sens. La quatrième génération de centrale impose également des conditions de fonctionnement très sévère pour les revêtements durs. L’idée principale de ce travail de thèse est de renforcer des nuances commerciales de superalliages base nickel avec des particules micrométriques et sub-micrométriques d’alumine par plasma d’arc transféré, Cold Spray et coprojection plasma simultanée de poudre et de suspension.Pour les dépôts PTA, l’analyse des dépôts a montré un raffinement de la microstructure mais une répartition inhomogène de l’alumine. L’ajout d’alumine n’a pas influé sur la microdureté des dépôts mais a permis d’améliorer la résistance à l’usure abrasive sous air. Les dépôts obtenus par projection plasma, en combinant projection classique de poudre et de suspension d’alumine, ont montrés un meilleur comportement tribologique sous conditions particulières. Les effets de l’ajout d’alumine dans la matrice ont été étudiés en observant la microstructure et en comparant les propriétés mécaniques des dépôts (micro dureté, et tests tribologiques représentatifs de l’application) pour différents taux de renforts (de 0 à 13% pds)In nuclear plants, the replacement of hardfacing Stellite, a cobalt-base alloy, on parts of the piping system in connection with the reactor has been investigated since the late 60’s. Various Fe-base or Ni-base alloys, Co-free or with a low content of Co, have been developed in this aim. The 4th generation nuclear plants impose additional or more stringent requirements for hardfacing materials. The idea developed in this work is to reinforce commercial nickel base alloy with addition of micrometric and sub-micrometric alumina particles by Plasma Transferred Arc welding, Cold Spray and simultaneous conventional and suspension plasma spray.For PTA Coatings, the examination of coatings revealed a refinement of the microstructure but an inhomogeneous alumina distribution. The addition of alumina particles did not improve the micro-hardness of coatings but improve their resistance to ambient air abrasive wear.The coatings prepared by plasma spraying, combining powder of metallic matrix and suspension of ceramic particles, showed better tribological performance under particular conditions. The effect of the addition of ceramic particles in the matrix was investigated by observing the microstructure of coatings, and comparing their mechanical behavior (micro hardness and tribological tests representative of the application) for different ceramic particle contents (from 0 to 13 wt%)
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Sudikas, Saulius. "Treatment of iliac and femoral artery atherosclerotic lesions by compound endovascular and open surgery methods. Evaluation of results." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20121024_114311-83183.
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The aim of the study is to evaluate the efficacy of percutaneous transluminal angioplasty in reduction of the lower limb ischemia and to investigate the influence of this procedure on the lower limb salvage rate. The introduction defines the objectives and tasks of the study, includes a literature review, a summary of the main problems related to the theme. A separate chapter describes the research methodology. The study analysed the treatment results of 146 patients who underwent the iliac artery percutaneous transluminal angioplasty. The following PTA efficacy criteria were determined - the increase of ankle-brachial index and the decrease of ischemia according to Fontaine stages of limb ischemia. It was also found that the substantial PTA effect of the iliac artery and the need for additional interventions become evident during the early postoperative period (1–7 days after PTA), and the effect of angioplasty decreases gradually during one year follow-up after the procedure. To arrest the progression of ischemia an additional endovascular procedure or an open surgery of femoral, popliteal and the crural arteries is necessary. The majority of these operations or procedures are reconstructive operations of the femoral, popliteal and the crural arteries. The effectiveness of the iliac artery PTA depends on the stage of lower limb ischemia. The need of an additional intervention is determined by the nature of lesion of the femoral arteries and the increase in ankle-brachial... [to full text]Tyrimo tikslas – nustatyti klubo arterijų perkutaninės transliuminalinės angioplastikos veiksmingumą mažinant apatinių galūnių išemiją ir ištirti, kokios įtakos ši gydomoji procedūra turi galūnių amputacijos dažniui. Įvade išdėstomi tyrimo tikslai bei uždaviniai, pateikiama literatūros apžvalga, kurioje apibendrinamos pagrindinės su nagrinėjama tema susijusios problemos. Atskirame skyriuje aprašyta tyrimo metodika. Disertacijoje išnagrinėti 146 pacientų, kuriems atlikta klubo arterijų perkutaninė transliuminalinė angioplastika, gydymo rezultatai. Nustatyta, kad kriterijai angioplastikos veiksmingumui įvertinti – kulkšnies-žasto indekso pokytis, išemijos sumažėjimas pagal Fontaine’o galūnės išemijos stadijas. Taip pat nustatyta, kad klubo arterijos PTA pakankamas efektas ir papildomų intervencijų poreikis daugiausia išryškėja ankstyvuoju pooperaciniu laikotarpiu (iki 7 dienų po PTA), o PTA rezultatai laipsniškai blogėja per vienerius metus. Išemijos progresavimui sustabdyti reikalinga šlaunies, pakinklio ir blauzdos arterijų papildoma endovaskulinė arba atviroji operacija, dažniausiai – rekonstrukcinės arterijų operacija. Klubo arterijų angioplastikos veiksmingumas priklauso nuo išemijos stadijos. Papildomos intervencijos poreikį po PTA lemia šlaunies arterijų pažeidimo pobūdis, kulkšnies-žasto indekso pokytis mažiau negu 0,15. Bendras pacientų sergamumas kitomis ligomis pakankamos angioplastikos ir papildomų intervencijų grupėje buvo vienodas. Iš tirtų periferinių arterijų... [toliau žr. visą tekstą]
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Ibenthal, Miriam [Verfasser], Thomas [Akademischer Betreuer] Ptak, Thomas [Gutachter] Ptak, and Gudrun [Gutachter] Massmann. "Marine and terrestrial influence on submarine groundwater discharge in coastal waters connected to a peatland / Miriam Ibenthal ; Gutachter: Thomas Ptak, Gudrun Massmann ; Betreuer: Thomas Ptak." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1211556824/34.
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Hinostroza, Segura Darryl Helmut. "Proyecto constructivo Planta de Tratamiento de Aguas Residuales Taboada – PTAR Taboada." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2013. https://hdl.handle.net/20.500.12672/14297.
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Describe del Proyecto Planta de Tratamiento de Aguas Residuales Taboada - PTAR TABOADA, la cual permitirá el tratamiento de las aguas residuales, vertidas por 27 distritos de Lima y Callao a través de los colectores Interceptor Norte, Comas-Chillón y de la Línea de Impulsión Sarita Colonia, antes de su vertimiento final hacia el mar a través de un emisario submarino, cumpliendo con los parámetros de calidad exigidos en la zona costera del cuerpo receptor, según lo establecido en la Ley de Recursos Hídricos(Ley 29338), que regula el uso y gestión integrada de los recursos hídricos.
Trabajo de suficiencia profesional
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Sbardelloto, Gabriela. "Propriedades psicométricas da versão em português do Posttraumatic Cognitions Inventory (PTCI)." Pontifícia Universidade Católica do Rio Grande do Sul, 2010. http://hdl.handle.net/10923/4859.
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Previous issue date: 2010The main goal of this study was to adapt and validate the Brazilian Portuguese version of the Posttraumatic Cognitions Inventory (PTCI). In order to achieve this purpose, the present dissertation is presented in four articles. The first theoretical article describes stressful events, Acute Stress Disorder (ASD), Posttraumatic Stress Disorder (PTSD), including information on historical development, conceptualization, symptomathology and prevalence. The second theoretical article debates on the PTSD cognitive processing. The most relevant theories related to the development of this disorder are presented. The relationship between the cognitive processing of the traumatic experience and the development of PTSD is argued. The third article presents the process of translation, adaptation and content validation of the Brazilian Portuguese version of the PTCI, named Inventário de Cognições Pós-Traumáticas. This process involved five steps: (1) translation; (2) back translation; (3) correction and semantic adaptation; (4) content validation by professional experts (judges); and (5) evaluation by a target population sample through a verbal-numbered scale. A good comprehension of the instrument was demonstrated. The fourth article presents the data of the PTCI psychometric properties analysis due to compose the inventory construct validation through techniques of internal consistency, factorial, convergent and discriminative analysis. To investigate the differences regarding posttraumatic cognitions three groups were created: (a) 20 individuals with a trauma history and PTSD diagnosis (PTSD group); (b) 20 individuals with a trauma history without PTSD diagnosis (TRAUMA+ group); and (c) 20 individuals without trauma history within the last three years and without PTSD diagnosis(TRAUMA- group).The following instruments were used: Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Childhood Trauma Questionnaire (CTQ), Davidson Trauma Scale (DTS) and Screen for Posttraumatic Stress Symptoms (SPTSS). The data suggests that the Brazilian version of the PTCI is sensitive enough to discriminate dysfunctional trauma-related cognitions involved in the development and maintenance of PTSD.
O objetivo principal deste estudo foi adaptar e validar a versão em português do Posttraumatic Cognitions Inventory (PTCI). Para alcançar esse propósito, a presente dissertação é apresentada em quatro artigos. O primeiro artigo teórico descreve eventos estressores, Transtorno de Estresse Agudo (TEA) e Transtorno de Estresse Pós-Traumático (TEPT), incluindo informações sobre desenvolvimento histórico, conceitualização, sintomatologia e prevalência. O segundo artigo teórico discute o processamento cognitivo no TEPT. São apresentadas as teorias mais relevantes relacionadas ao desenvolvimento desse transtorno. Discute-se a relação entre o processamento cognitivo da experiência traumática e o desenvolvimento do TEPT. O terceiro artigo apresenta o processo de tradução, adaptação e validação de conteúdo da versão em português do PTCI, denominada Inventário de Cognições Pós-Traumáticas. O processo envolveu cinco etapas: (1) tradução; (2) retradução; (3) correção e adaptação semântica; (4) validação do conteúdo por profissionais da área (juízes); e (5) avaliação por amostra de população-alvo, por intermédio de uma escala verbal-numérica. Uma boa compreensão do instrumento foi demonstrada. O quarto artigo apresenta os dados da análise das propriedades psicométricas do PTCI para compor a validação de construto do inventário através de técnicas de consistência interna, análise fatorial, convergente e discriminante. Para investigar as diferenças referentes às cognições pós-traumáticas foram criados três grupos: (a) 20 indivíduos com histórico de trauma e diagnóstico de TEPT ( grupo TEPT); (b) 20 indivíduos com histórico de trauma e sem diagnóstico de TEPT(grupo TRAUMA +) e (c) 20 indivíduos sem histórico de trauma nos últimos três anos e sem diagnóstico de TEPT (grupo TRAUMA -).Os seguintes instrumentos foram utilizados: Inventário Beck de Depressão (BDI), Inventário Beck de Ansiedade (BAI), Questionário de Traumas na Infância (CTQ), Escala Davidson de Trauma (DTS) e o Instrumento de Rastreio para Sintomas de Estresse Pós-Traumático (SPTSS). Os dados sugerem que a versão brasileira do PTCI é suficientemente sensível para discriminar cognições disfuncionais relacionadas ao trauma envolvidas no desenvolvimento e na manutenção do TEPT.
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Sanikommu, Ramanarayana Reddy. "Design and Implementation of Bandgap Reference Circuits." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-398.
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An important part in the design of analog integrated circuits is to create reference voltages and currents with well defined values. To accomplish this on-chip, so called bandgap reference circuits are commonly used. A typical application for reference voltages is in analog-to-digital conversion, where the input voltage is compared to several reference levels in order to determine the corresponding digital value. The emphasis in this thesis work lies on theoretical understanding of the performance limitations as well as the design of a bandgap reference circuit, BGR.
In this project, a comprehensive study of bandgap circuits is done in the first stage. Then investigations on parameter variations like Vdd, number of bipolars, W/L of PMOS, DC gain of Opamp, RL and CL are done for a PTAT current generator circuit. This PTAT current generator circuit is a part of the implemented BGR circuit based on [10], which is capable of producing an output reference voltage of 0.75 V when the supply voltage is 1 V. All of these circuits are implemented in a 0.35u CMOS technology.
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Ruiz, Samira Lea Medina [UNESP]. "Efeito do oxigênio nas propriedades anelásticas e biocompatibilidade das ligas de Ti-8%pTa e Ti-16%pTa utilizadas como biomaterial." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/94393.
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ruiz_slm_me_bauru.pdf: 2192479 bytes, checksum: 69f94a0515d295047a14f126eaa6fb64 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O crescente aumenta na expectativa de vida da população tem resultado numa igual demanda e procura por biomateriais metálicos. Biomateriais metálicos são utilizados na substituição ou recuperação de ombros, joelhos, quadril e cotovelos. As ligas a base de Ti são materiais promissores para tais fins, pois apresentam uma excelente biocompatibilidade, ótima resistência à corrosão em meio biológico. Essas características são grandemente influenciadas pela presença de elementos substitucionais e oxigênio intersticial e a técnica do atrito interno constitui um aliado bastante importante na análise dos resultados deste trabalho. Dessa forma, o objetivo deste trabalho é analisar a influência do exigênio intersticial nas propriedades das ligas Ti-8Ta e Ti-16Ta (% em peso). As medidas de atrito interno foram utilizadas para obtenção do módulo de elasticidade dinâmico das ligas estudadas, pois esta grandeza está experimentalmente associada ao amortecimento das vibrações livres do sistema, a dissipação de energia elástica e a frequencia de oscilação do sistema. Para tais medidas empregou-se um Pêndulo de Torção com frequencia de oscilação de aproximadamente 30Hz e temperatura na faixa de 230 a 350K. As ligas estudadas passaram por processos de tratamento térmico e dopagens com oxigênio e foram caracterizadas por medidas de densidade, difração de raios X e posterior refinamento de Rietveld, microdureza, módulo de elasticidade e testes de citotoxicidade in vitro. Os testes iniciais de biocompatibilidade mostram que não houve nenhuma resposta citotóxica, originando resposta celular satisfatória. As medidas de microdureza apresentam valores menores que os encontrados na literatura e as medidas de raios X mostram picos característicos da fase 'alfa' do titânio. Na análise de Rietveld verificou-se a presença de estrutura martensítica 'alfa' e fase 'beta' para...
The accelerating increase in life expectancy of the population has resulted in greater demand and more searches for metallic biomaterials. Metallic are extensively used in the replacement or restoration fo shoulders, knees, hips and elbows. Ti-based alloys are promising materials for such purposes, because they present excellent biocompatibility, a great mechanical strengh/density relation and a high corrosion resistance in a biological medium. These characteristics are greatly influenced by the presence of substitutional elements and interstitial oxygen. The internal friction technique is a very important ally in the analysis of the results of this work. Thus, the purpose of this work is to analyze the influence of insterstitial oxygen on the properties of Ti-8Ta and Ti-16Ta alloys (wt%). Internal friction measurements were used to obtain the dynamic elasticity modulus of the alloys studied, because this quantity is experimentally associated with the damping of free vibration of the sytem, which is related to the elastic energy dissipation and the oscillation frequency of the system. For such measurements, a torsion pendulum was employed, with an oscillation frequency of approximately 30 Hz and temperature in the range of 230-350 K. The alloys underwent heat treatment and oxygen doping processes, and were characterized by density, x-ray diffraction and subsequent refinement of Rietveld, microhardness and elasticity modulus measurements, and in vitro cytotoxicity tests. The initial biocompatibility tests showed that there was no cytotoxic answer, giving origin to a satisfactory cellular response. Microhardness measurements had values less than found in the literature, and x-rays showed characteristic peak of the titanium 'alfa' phase. In the Rietveld analysis, observed were the presence of martensitic 'alfa' structure and a 'beta' phase for all sample and conditions studied. The ... (Complete abstract click electronic access below)
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Ruiz, Samira Lea Medina. "Efeito do oxigênio nas propriedades anelásticas e biocompatibilidade das ligas de Ti-8%pTa e Ti-16%pTa utilizadas como biomaterial /." Bauru : [s.n.], 2010. http://hdl.handle.net/11449/94393.
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Orientador: Carlos Roberto GrandiniBanca: Paulo Afonso Silveira Francisconi
Banca: Ana Paula Rosifini Alves Claro
O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp
Resumo: O crescente aumenta na expectativa de vida da população tem resultado numa igual demanda e procura por biomateriais metálicos. Biomateriais metálicos são utilizados na substituição ou recuperação de ombros, joelhos, quadril e cotovelos. As ligas a base de Ti são materiais promissores para tais fins, pois apresentam uma excelente biocompatibilidade, ótima resistência à corrosão em meio biológico. Essas características são grandemente influenciadas pela presença de elementos substitucionais e oxigênio intersticial e a técnica do atrito interno constitui um aliado bastante importante na análise dos resultados deste trabalho. Dessa forma, o objetivo deste trabalho é analisar a influência do exigênio intersticial nas propriedades das ligas Ti-8Ta e Ti-16Ta (% em peso). As medidas de atrito interno foram utilizadas para obtenção do módulo de elasticidade dinâmico das ligas estudadas, pois esta grandeza está experimentalmente associada ao amortecimento das vibrações livres do sistema, a dissipação de energia elástica e a frequencia de oscilação do sistema. Para tais medidas empregou-se um Pêndulo de Torção com frequencia de oscilação de aproximadamente 30Hz e temperatura na faixa de 230 a 350K. As ligas estudadas passaram por processos de tratamento térmico e dopagens com oxigênio e foram caracterizadas por medidas de densidade, difração de raios X e posterior refinamento de Rietveld, microdureza, módulo de elasticidade e testes de citotoxicidade in vitro. Os testes iniciais de biocompatibilidade mostram que não houve nenhuma resposta citotóxica, originando resposta celular satisfatória. As medidas de microdureza apresentam valores menores que os encontrados na literatura e as medidas de raios X mostram picos característicos da fase 'alfa' do titânio. Na análise de Rietveld verificou-se a presença de estrutura martensítica 'alfa' e fase 'beta' para ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The accelerating increase in life expectancy of the population has resulted in greater demand and more searches for metallic biomaterials. Metallic are extensively used in the replacement or restoration fo shoulders, knees, hips and elbows. Ti-based alloys are promising materials for such purposes, because they present excellent biocompatibility, a great mechanical strengh/density relation and a high corrosion resistance in a biological medium. These characteristics are greatly influenced by the presence of substitutional elements and interstitial oxygen. The internal friction technique is a very important ally in the analysis of the results of this work. Thus, the purpose of this work is to analyze the influence of insterstitial oxygen on the properties of Ti-8Ta and Ti-16Ta alloys (wt%). Internal friction measurements were used to obtain the dynamic elasticity modulus of the alloys studied, because this quantity is experimentally associated with the damping of free vibration of the sytem, which is related to the elastic energy dissipation and the oscillation frequency of the system. For such measurements, a torsion pendulum was employed, with an oscillation frequency of approximately 30 Hz and temperature in the range of 230-350 K. The alloys underwent heat treatment and oxygen doping processes, and were characterized by density, x-ray diffraction and subsequent refinement of Rietveld, microhardness and elasticity modulus measurements, and in vitro cytotoxicity tests. The initial biocompatibility tests showed that there was no cytotoxic answer, giving origin to a satisfactory cellular response. Microhardness measurements had values less than found in the literature, and x-rays showed characteristic peak of the titanium 'alfa' phase. In the Rietveld analysis, observed were the presence of martensitic 'alfa' structure and a 'beta' phase for all sample and conditions studied. The ... (Complete abstract click electronic access below)
Mestre
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Yovanovich, Marcos. "Oxidação eletroquímica do ácido fórmico em eletrólito ácido e básico utilizando eletrocatalisadores PtBi/C e PdBi/C preparados pelo método de redução via borohidreto de sódio adição rápida." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-22082016-155447/.
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PtBi/C e PdBi/C foram preparados em diferentes razões atômicas (100:0, 90:10, 80:20, 70:30, 60:40 e 50:50) pelo método de redução via borohidreto de sódio (com adição total da solução de borohidreto em uma única etapa) utilizando H2PtCl6.6H2O, Pd(NO3)2, (BiNO3)3.5H2O como fonte de metais, Vulcan® (XC72-Cabot) como suporte de carbono e com uma carga metálica correspondente a 20% em massa. Os eletrocatalisadores obtidos foram caracterizados por difração de raios-X (DRX), microscopia eletrônica de transmissão (MET) e voltametria cíclica (VC). A atividade dos diferentes materiais preparados para a oxidação eletroquímica do ácido fórmico foi realizada em eletrólito ácido e alcalino utilizando-se as técnicas de voltametria cíclica, e cronoamperometria. Para estes estudos foi utilizado a técnica do eletrodo de camada fina porosa. A caracterização eletroquímica permitiu comparar o desempenho eletroquímico da platina e paládio, além de avaliar o benefício da presença do bismuto nas razões atômicas propostas. Os difratogramas de raio-X (DRX) confirmaram para todos os compostos de PtBi/C e PdBi/C a formação da estrutura cúbica de face centrada (cfc) característicos da rede cristalina da platina e do Paládio respectivamente. Outros picos encontrados foram associados a presença de fases de óxido de bismuto em ambos os compostos, PtBi/C e PdBi/C. A microscopia eletrônica de transmissão (MET) indicou que a presença de maiores teores de bismuto não acarretaram em aumento do tamanho médio da partícula. Os resultados eletroquímicos em meio alcalino indicaram que ainda é necessário uma otimização da concentração de ácido fórmico para que possamos observar melhores resultados quanto à adição de bismuto na platina ou paládio, no entanto os estudos em meio ácido mostraram o efeito benéfico da adição de bismuto tanto para platina quanto para o paládio.PtBi/C and PdBi/C were prepared with different atomic ratios (100:0, 90:10, 80:20, 70:30, 60:40 and 50:50) by sodium borohydride reduction method (with total addition of the borohydride solution in just one step) using H2PtCl6.6H2O, Pd(NO3)2, (BiNO3)3.5H2O as source of metals, Vulcan® (XC72-Cabot) as carbon support and a metallic charge correspondent to 20% mass. The obtained electrocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and cyclic voltammetry (CV). The activity of the different materials used for the formic acid electrochemical oxidation was performed in acid and alkaline electrolyte through cyclic voltammetry and chronoamperometry, using the porous thin-film electrode technique. The electrochemical characterization allowed for the comparison between the platinum and palladium electrochemical performance, as well as the evaluation of the benefit of having bismuth in the proposed atomic ratios. The X-ray diffraction (XRD) diffractograms confirmed, for every PtBi/C and PdBi/C compounds, the formation of the face-centered cubic structure (fcc) distinctive to platinum and palladiums crystalline net, respectively. Other peaks were found associated to the presence of bismuth oxide phases in both compounds, PtBi/C and PdBi/C. The transmission electron microscopy (TEM) indicated that a higher bismuth presence did not result in a larger particle size. The electrochemical results in alkaline medium indicated that an optimization on formic acid concentration is still necessary so that better results concerning bismuth addition to platinum or palladium could be observed, although the studies done in acid medium presented the beneficial effect of bismuth addition to both platinum and palladium.
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Kamdi, Zakiah. "Characterisation, wear and corrosion of tungsten carbide based HVOF and PTAW coating." Thesis, University of Nottingham, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.659208.
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In this study, three types of WC based coating were characterised in terms of both microstructure and performance in abrasive wear, corrosion and a combination of both. The coating types were high velocity oxy-fuel (HVOF) sprayed WC-Co and WC-CoCr and a tungsten carbide-nickel alloy weld-overlay plasma transferred arc welded (PTAW) coating . For the PTAW deposit, the nominal carbide content was varied. All coatings were characterised using x-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) analysis. The abrasive wear behaviour of the coatings was examined using micro-scale abrasion and dry sand rubber wheel (DSRW) abrasive testing. Corrosion behaviour of the coatings in sulphuric acid and alkaline drilling fluid were assessed through potentiodynamic testing. In addition, the combined effect of abrasion and corrosion was assessed through the use of micro-scale abrasion. Both HVOF coatings contained angular carbides with size of N 0.5 to 5 ~lm. The main carbide is WC in both HVOF sprayed coatings. In contrast, the carbides in the PTAW coating are a combination of WC and W2C, are spherical in shape and are much larger than those in the HVOF-sprayed coatings, being N 40 to 150 f.lm in diameter. Due to variation of carbide distribution through the coating resulting from carbide sinking during solidification in PTAW coatings, the local carbide content is considered when discussing the coating behaviour. It has been shown that the wear behaviour is strongly dependent on the relative size of the carbide and the abrasive employed in the test. The wear rate was shown to decrease with increasing local carbide content in the PTAW coatings. The precipitates in the matrix phase of the PTAW coating actively contribute to increasing the wear resistance of these materials. Both HVOF coatings have similar wear resistances to each other when abraded with either alumina or silica abrasive in both the micro-scale abrasion and DSRW test. In micro-scale abrasion, the wear rate of PTAW with the largest fraction of carbides (65 wt%) was approximately 1.5 times that of the HVOF-sprayed coatings when abraded with alumina, but was more than ten times that of the HVOF-sprayed coatings when abraded with silica. In contrast, in DSRW abrasion, the wear rate of PTAW with the largest fraction of carbides (65 wt%) was approximately twice that of the HVOF-sprayed coatings when abraded with alumina, but was only around half of that of the HVOFsprayed coatings when abraded with silica.
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Cappello, Franck. "Ptah : etude d'une architecture massivement parallele a ressources equilibrees et communications compilees." Paris 11, 1994. http://www.theses.fr/1994PA112283.
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Les etudes realisees dans cette these ont pour objet de definir l'architecture d'un calculateur massivement parallele original, de verifier sa faisabilite et d'etudier ses performances. L'objectif est d'obtenir une architecture extensible comme les architectures massivement paralleles et dont l'efficacite reste proche de celle des calculateurs vectoriels. Apres avoir etudie les parametres de l'extensibilite et de l'efficacite, nous proposons une architecture massivement parallele a memoire distribuee dont les ressources sont equilibrees en performance. L'equilibrage des performances du cpu, de la memoire et du reseau consiste a augmenter les performances du reseau de 2 ordres de grandeurs. Il est possible d'obtenir un tel gain en combinant l'utilisation de liaisons series a haut debit et celle d'un nouveau modele de communication: la compilation des communications. La faisabilite de cette approche repose sur plusieurs points. D'abord, la majorite des references aux donnees dans les applications numeriques doivent etre compilables. Ceci est verifie par une analyse statistique qui rapporte que plus de 80% des references d'un ensemble representatif d'applications sont connues des la compilation. Ensuite, il faut determiner les contraintes architecturales. Notre etude indique que l'architecture doit etre fortement synchrone, que la memoire ne peut etre hierarchisee et que le processeur elementaire est de type vliw. Enfin, il faut verifier que la technologie actuelle permet d'obtenir les performances requises. Nous etudions donc en detail la structure des elements determinants du reseau. Les performances obtenues par simulation montrent que l'architecture remplit l'objectif initial et offre un gain en performance du reseau de communication d'un a deux ordres de grandeur par rapport aux architectures comparables
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Toledo, Quiñonez Jorge Hernán, and Quiñonez Freddy Julián Toledo. "Propuesta de la aplicación de la metodología beneficio costo (B/C) para la evaluación económica de proyectos de plantas de tratamiento de aguas residuales (PTAR): Caso PTAR del Cusco." Universidad Nacional de Ingeniería. Programa Cybertesis PERÚ, 2010. http://cybertesis.uni.edu.pe/uni/2010/toledo_qj/html/index-frames.html.
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Hadley, Julia C. "Glycation of Type I collagen in ocular tissues and tendon." Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286926.
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Lucizani, Jonhey Nazario. "O impacto econômico regional do Parque Tecnológico Itaipu (PTI)." Universidade Estadual do Oeste do Parana, 2012. http://tede.unioeste.br:8080/tede/handle/tede/2310.
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Previous issue date: 2012-09-06This work has prospected and analyzed the economic impacts of the Itaipu Technological Park (PTI), hereinafter referred to as impacts on income generation, production and jobs in the Parana, as the economy of the PTI. For this, we used the input-output matrix, using the search field in the PTI organizations to collect accounting information. This information led to the final demand by economic sector of the park, making it possible to design the input-output matrix. The results showed that as the value added to the economy of the PTI was R $ 27,186,350.04, with 55.5% went to employees, the final demand of the PTI was R $ 48,211,646.08, which enabled identify the income multipliers of the PTI is equal to 2.23, 1.52 employment and production equal to 2.28. The PTI was identified as a Park Structuring because accumulated regional experience and is intimately associated with the process of economic and technological development.
Este trabalho prospectou e analisou os impactos econômicos do Parque Tecnológico Itaipu (PTI), doravante denominado de impactos na geração de renda, produção e empregos na economia Paranaense, a partir da economia do PTI. Para isto, utilizou-se da matriz insumo-produto, utilizando pesquisa a campo nas organizações do PTI para coletar as informações contábeis. Estas informações geraram a demanda final do PTI por setor econômico, tornando-a possível projetar na matriz insumo produto. Os resultados apontaram que o valor adicionado do PTI para a economia foi de R$ 27.186.350,04, com 55,5 % foi destinado aos colaboradores, a demanda final do PTI foi R$ 48.211.646,08, a qual possibilitou identificar os multiplicadores de renda do PTI é igual a 2,23, emprego 1,52 e produção igual a 2,28. O PTI foi identificado como um Parque Estruturante, pois acumulou as experiências regionais e está intimamente associado ao processo de desenvolvimento econômico e tecnológico.
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Engelman, Kristi L. Templeton J. L. "Probing the influence of the Tp ligand on reactions of PtII and PtIV." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2010. http://dc.lib.unc.edu/u?/etd,2882.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2010.Title from electronic title page (viewed Jun. 23, 2010). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry. On t.p., Tp is followed by the symbol for prime.
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Wang, Chinhua. "Laser induced purely-thermal-wave interferometry (PTWI) using a novel photopyroelectric (PPE) instrument." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/NQ53796.pdf.
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McCafferty, Patrick Gabriel. "Optical and electrical investigation of the interfacial properties of PtSi Schotty barrier photodiodes." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295417.
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Adamson, Janet. "Structure and function of the platelet and T-cell activation antigen-1 (PTA1)." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367096.
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Gross, Abby Alicea-Ruth. "Evaluation of Amyloid Inhibitors: Cotinine, PTI-00703®, and Tetracycline." Thesis, Boston College, 2010. http://hdl.handle.net/2345/3764.
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Thesis advisor: Daniel A. KirschnerIn the present study, the ability of small compounds to inhibit the fibrillogenesis of beta-amyloid 12-28 was explored. Beta-amyloid 12-28 is a synthetic fragment of Alzheimer's beta-amyloid, which contains the core hydrophobic residues thought to be significant for fiber formation. Using x-ray diffraction, preliminary screening of over sixteen compounds was performed. Cotinine, PTI-00703®, and tetracycline were chosen because of their ease of solubility, the effect on the coherent domain size of the beta-crystallite subunit in the presence of chosen small molecules as shown by x-ray diffraction, as well as their presence in previously published literature. This conformational-driven inhibition of fibrillogenesis was explored in the current research using circular dichroism spectroscopy and x-ray diffraction. Circular dichroism spectroscopy revealed the nascent beta-sheet structure of beta-amyloid12-28 when first dissolved and only cotinine, out of all three inhibitors, was able to shift the equilibrium away from the fibrillogenic beta-sheet structure toward a random coil secondary structure after 36 hours of incubation. X-ray diffraction in this study demonstrated no change in hydrogen bond spacing at ~4.7Å and intersheet spacing at ~10-12Å both alone and in the presence of all small molecules. With increasing concentration of inhibitor, however, the widths of these reflections increased, indicating a decrease in the coherent domain size
Thesis (MS) — Boston College, 2010
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Biology
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Ribeiro, Hélio Ormeu. "Desenvolvimento de ligas para revestimento por PTA resistentes à cavitação." Florianópolis, SC, 2007. http://repositorio.ufsc.br/xmlui/handle/123456789/90341.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Ciências e Engenharia de MateriaisMade available in DSpace on 2012-10-23T08:50:21Z (GMT). No. of bitstreams: 1 210336.pdf: 6041832 bytes, checksum: 7041aad6235affc1f4899d991f0a0831 (MD5)
A erosão por cavitação deteriora componentes em serviço, tais como partes metálicas de bombas de água, válvulas e, em especial, pás de turbinas hidráulicas, sendo nesse último caso responsável por elevados prejuízos, ligados tanto aos custos da manutenção direta, como sobretudo às enormes perdas devido à interrupção na geração de energia elétrica. As pás de turbinas hidráulicas necessitam, portanto serem protegidas para que apresentem um maior tempo de operação e, um maior intervalo entre as intervenções de manutenção. Atualmente a principal solução consiste no revestimento superficial do substrato, em geral de aço carbono ou baixa-liga, pelo depósito de um material mais nobre por soldagem Dentre os materiais aplicados para revestimentos incluem-se aços inoxidáveis austeníticos, destacando-se os aços inoxidáveis ao Co, e ligas à base de Co, no entanto esses últimos são mais sensíveis a trincas, difíceis de esmerilhar e de mais alto custo. Nesse contexto este trabalho buscou formular, depositar e avaliar aços inoxidáveis ao Fe-Cr-Mn-Si-N, depositados pelo processo PTA, que tem como uma de suas principais características a grande flexibilidade na formulação e deposição de novas ligas. A resistência à erosão por cavitação avaliada segundo a norma ASTM G 32-85, ao lado da microestrutura caracterizada por microscopia ótica e MEV, da composição química determinada por ASS, da análise das fases presentes nos revestimentos antes e após a erosão por cavitação avaliadas no EDX, da qualidade da superfície dos depósitos avaliados por END, serviram como critérios para avaliar os revestimentos depositados. Verificou-se que os revestimentos apresentaram boa soldabilidade (sem trincas de solidificação, baixa porosidade, boa molhabilidade, bom acabamento superficial), baixo custo de produção e especialmente a liga L03* (0,03%C; 0,35% N; 13,2%Cr; 11,8% Mn; 2,8%Si; bal %Fe), dureza e resistência à erosão por cavitação bem próxima as principais ligas comerciais destinadas a essa função.
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RAMÍREZ, CEDEÑO MONSERRAT. "EFECTOS DEL TURISMO EN LA ACTIVIDAD AGRÍCOLA Y EL PATRIMONIO BIOCULTURAL: EL PTI LITIBÚ Y LA COMUNIDAD DE HIGUERA BLANCA, NAYARIT." Tesis de Licenciatura, UNIVERSIDAD AUTÓNOMA DEL ESTADO DE MÉXICO, 2018. http://hdl.handle.net/20.500.11799/98758.
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En la presente investigación se analiza los efectos del turismo en la actividad agrícola y el patrimonio biocultural a partir del surgimiento del Proyecto Turístico Integral (PTI) Litibú en la comunidad de Higuera Blanca, Nayarit. Esto porque el turismo como fenómeno social, de acuerdo con Monterrubio (2011) genera efectos que transforman positiva o negativamente las condiciones de vida de los individuos que participan directa e indirectamente en esta actividad.
Los efectos generados en la comunidad local se reflejan en las dimensiones ambiental, económica y sociocultural, por ejemplo el cambio de uso de suelo, la transformación del paisaje y la competencia intersectorial están asociados al cambio de actividades como el turismo por la agricultura, siendo esta última una actividad que hace uso de conocimientos desarrollados por las personas para la producción de alimentos como verduras, frutos, granos, entre otros, y productos no comestibles, pero importantes para la reproducción social de estas, de ahí que sea una de las actividades más importantes tanto para las comunidades rurales como para la sociedad, esto porque la actividad agrícola no sólo provee alimentos que satisfaces las necesidades básicas de la sociedad y de los animales (ganado), sino que además en esta se hace uso de saberes, conocimientos y prácticas para el uso, manejo y aprovechamiento de los recursos naturales, de ahí que Wolf (citado en Rojas, 1990) llamaba a la agricultura “un aspecto esencial de la existencia”.
Por tanto la relación entre el turismo y la agricultura se da a partir de que esta última forma parte del patrimonio biocultural que dan vida a la identidad y diversidad de cada uno de los pueblos. Sin embargo esta relación puede ser positiva o negativa de acuerdo a la modalidad de turismo que se realice en la comunidad de destino.
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Para conocer los efectos que tiene el turismo sobre la actividad agrícola y el patrimonio biocultural a partir del surgimiento del PTI Litibú desde la opinión de la población de Higuera Blanca, Nayarit, se hizo uso de la investigación cualitativa y sus técnicas como la entrevista a profundidad y la observación no participativa, lo que permitió alcanzar el objetivo general y los específicos del presente trabajo. Cabe señalar que una de las ventajas de la investigación cualitativa es que permite recoger datos descriptivos, es decir, las propias palabras, habladas o escritas así como entender los fenómenos sociales desde la propia perspectiva del actor, esto se hizo a partir de entrevistas a profundidad a residentes locales, como agricultores de la comunidad Higuera Blanca, Nayarit.
Algunos de los resultados de la presente investigación son:
1. cambios generados en la actividad agrícola y el patrimonio biocultural, que se reflejan en la disminución de cultivos agrícolas para la producción de alimentos, el cambio de zonas de cultivos, el fin de la producción, en el trabajo de campo de las personas responsables y los conocimientos y prácticas que se usan esta actividad;
2.cambios ambientales negativos del turismo como transformación y aprovechamiento del paisaje natural-cultural, cambio de uso de suelo y la rivalidad de los recursos naturales (turismo-agricultura) como resultado de la construcción de la superestructura del PTI Litibú;
3.cambios económicos positivos del turismo como la generación de empleos y los ingresos económicos de manera directa (PTI Litibú) e indirecta (Rancho Montalbena/vista paraíso tours & activities, rentas de cuartos, venta de alimentos y bebidas [cocinas económicas, restaurantes, puestos de comida y tiendas] a trabajadores del rancho, hoteles y a turistas) en la población receptora; y los negativos como el cambio de actividades económicas tradicionales debido a la competencia intersectorial entre la agricultura y turismo;
4.cambios socioculturales positivos del turismo como el desarrollo de infraestructura (carreteras, transporte, el empedrado de calles, obras de agua potable, drenaje, energía eléctrica, puentes, banquetas, acceso al mar, ampliación
iv
de telesecundaria y centro de salud, remodelación de plaza pública, jardines y unidad deportiva), y negativos como el desplazamiento de la actividad agrícola que insidió en la perdida de los conocimientos, practicas, usos y manejos de los recursos relacionados con la actividad desplazada, y al mismo tiempo generó una vulnerabilidad del patrimonio biocultural (diversidad biológica y cultural), debido a la inserción de los jóvenes a la actividad turística de manera directa e indirecta ocasiono que este patrimonio ya no se transmitiera de generación en generación.SEP, UAEMEX
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Chang, Xiaoli [Verfasser], and P. [Akademischer Betreuer] Nick. "PTI versus ETI - Defence signalling diverges at stilbenic biosynthesis in PTI and ETI, and in resistant and susceptible Vitis cells / Xiaoli Chang. Betreuer: P. Nick." Karlsruhe : KIT-Bibliothek, 2012. http://d-nb.info/1022123912/34.
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Sbardelloto, Gabriela. "Propriedades psicom?tricas da vers?o em portugu?s do Posttraumatic Cognitions Inventory (PTCI)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2010. http://tede2.pucrs.br/tede2/handle/tede/714.
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Previous issue date: 2010-01-27O objetivo principal deste estudo foi adaptar e validar a vers?o em portugu?s do Posttraumatic Cognitions Inventory (PTCI). Para alcan?ar esse prop?sito, a presente disserta??o ? apresentada em quatro artigos. O primeiro artigo te?rico descreve eventos estressores, Transtorno de Estresse Agudo (TEA) e Transtorno de Estresse P?s-Traum?tico (TEPT), incluindo informa??es sobre desenvolvimento hist?rico, conceitualiza??o, sintomatologia e preval?ncia. O segundo artigo te?rico discute o processamento cognitivo no TEPT. S?o apresentadas as teorias mais relevantes relacionadas ao desenvolvimento desse transtorno. Discute-se a rela??o entre o processamento cognitivo da experi?ncia traum?tica e o desenvolvimento do TEPT. O terceiro artigo apresenta o processo de tradu??o, adapta??o e valida??o de conte?do da vers?o em portugu?s do PTCI, denominada Invent?rio de Cogni??es P?s-Traum?ticas. O processo envolveu cinco etapas: (1) tradu??o; (2) retradu??o; (3) corre??o e adapta??o sem?ntica; (4) valida??o do conte?do por profissionais da ?rea (ju?zes); e (5) avalia??o por amostra de popula??o-alvo, por interm?dio de uma escala verbal-num?rica. Uma boa compreens?o do instrumento foi demonstrada. O quarto artigo apresenta os dados da an?lise das propriedades psicom?tricas do PTCI para compor a valida??o de construto do invent?rio atrav?s de t?cnicas de consist?ncia interna, an?lise fatorial, convergente e discriminante. Para investigar as diferen?as referentes ?s cogni??es p?s-traum?ticas foram criados tr?s grupos: (a) 20 indiv?duos com hist?rico de trauma e diagn?stico de TEPT ( grupo TEPT); (b) 20 indiv?duos com hist?rico de trauma e sem diagn?stico de TEPT(grupo TRAUMA +) e (c) 20 indiv?duos sem hist?rico de trauma nos ?ltimos tr?s anos e sem diagn?stico de TEPT (grupo TRAUMA -). Os seguintes instrumentos foram utilizados: Invent?rio Beck de Depress?o (BDI), Invent?rio Beck de Ansiedade (BAI), Question?rio de Traumas na Inf?ncia (CTQ), Escala Davidson de Trauma (DTS) e o Instrumento de Rastreio para Sintomas de Estresse P?s-Traum?tico (SPTSS). Os dados sugerem que a vers?o brasileira do PTCI ? suficientemente sens?vel para discriminar cogni??es disfuncionais relacionadas ao trauma envolvidas no desenvolvimento e na manuten??o do TEPT.
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Eychmüller, Alexander, Wei Liu, Danny Haubold, Bogdan Rutkowski, Martin Oschatz, Rene Hübner, Matthias Werheid, et al. "Self – supporting Hierarchical Porous PtAg Alloy Nanotubular Aerogels as Highly Active and Durable Electrocatalysts." American Chemical Society, 2018. https://tud.qucosa.de/id/qucosa%3A30955.
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Developing electrocatalysts with low cost, high activity, and good durability is urgently demanded for the wide commercialization of fuel cells. By taking advantage of nanostructure engineering, we fabricated PtAg nanotubular aerogels (NTAGs) with high electrocatalytic activity and good durability via a simple galvanic replacement reaction between the in situ spontaneous gelated Ag hydrogel and the Pt precursor. The PtAg NTAGs have hierarchical porous network features with primary networks and pores from the interconnected nanotubes of the aerogel and secondary networks and pores from the inter-connected thin nanowires on the nanotube surface, and show very high porosities and large specific surface areas. Due to the unique structure, the PtAg NTAGs exhibit greatly enhanced electrocatalytic activity towards formic acid oxidation, reaching 19 times higher metal based mass current density as compared to the commercial Pt black. Furthermore, the PtAg NTAGs show outstanding structural stability and electrochemical durability during the electrocatalysis. Noble metal based NTAGs are promising candidates for applications in electrocatalysis not only for fuel cells, but also for other energy related systems.
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Prakash, N. Swamy. "Cristallographie de surfaces par diffraction de photoélectrons W(110), Pt(111) et PtNi(111) /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37617711v.
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Dickinson, Mark Patrick. "Constructing a Culture Cycle : an Upcycling Waste Centre in PTA CBD." Diss., University of Pretoria, 2018. http://hdl.handle.net/2263/63629.
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Upcycling in today’s society is still relatively rare, with most
upcycling occurring in works by artists and product designers.
This ‘creative reuse’ is a form of minimising waste products in a
more effective process than recycling. This study deals with the
design of an upcycling centre and how interior architecture is a
framework for the upliftment of the host building in the Pretoria
CBD, the model inhabitants (namely waste pickers and crafts
people), waste materials and the surrounding environment.
Many people perceive the self-starter occupation of streetwaste
picking as being dirty and inferior. However, those who
practice waste picking usually do so as a means of survival,
and can offer valuable assistance in environmental sustainability.
Waste pickers are often isolated as a social group – unable
to reach higher income levels or living conditions. Ignorance
around this informal economic sector has led to a divided
and fragmented society, particularly within the Pretoria CBD
(identified as the location for the intervention).
Finding sustainable solutions to waste reuse and job creation,
such as this proposed upcycling centre, which actively engage
various members of society (in this case, waste pickers, crafts
people and the broader community) is important. This is
because such programmes can be beneficial to communities
living in dense neighbourhoods, as they can provide the key
blocks of cohesiveness and symbiosis for building a prosperous
future.
The interior architecture discipline is relevant here as being
a tangible framework to enable cultural production of new
objects, environmental sustainability, cultivation of human
capital and a support system for model inhabitants. Waste
material and discarded products can inform the character of
an interior space, and reflect user intervention with built forms
that echo the activity and daily routines within the community.
As a facilitator, the interior architecture has been imagined to
stimulate, inspire, revive and be perceived as a cyclic journey
of renewal. This is the concept which governs the experience,
activity and process for users entering the proposed upcycling
centre.
This proposed intervention of the identified Minty’s Tyres
building utilises three theories to guide and inform its
responses. Firstly, environmental psychology theory guides
the alteration of the building to respond to community and
social inclusion strategies. Secondly, adaptive reuse theory
informs the alteration of the building in response to the new
programme as a form of upcycling and improving the building’s
user experience and resource efficiency. Finally, regenerative
design theory based on restorative actions and technology
is consulted to produce a system that is both efficient and
sustainable. The architecture itself (i.e. the physical building,
materials and structure) is developed alongside the actual
site and ecological surroundings.Mini Dissertation MInt(Prof)--University of Pretoria 2018.
Architecture
MInt(Prof)
Unrestricted
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Lechner, Olga [Verfasser], and Emil [Akademischer Betreuer] Roduner. "Spectroscopic investigation of zeolite supported PdAg and PtAg bimetallic clusters / Olga Lechner. Betreuer: Emil Roduner." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2012. http://d-nb.info/1024490750/34.
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Hall, Audrey Rose. "Nonstandardized Assessment of Cognitive-Communication Abilities Following Pediatric Traumatic Brain Injury (pTBI): A Scoping Review." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1588149045710777.
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Filho, Adroaldo Josà Silva de Moura. "AvaliaÃÃo de juntas soldadas dos aÃos AISI 8630M e ASTM A182 F22 amanteigadas pelo processo PTA com a liga de nÃquel UNS N06625." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13420.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoGrande parte do petrÃleo nacional encontra-se em ambiente offshore, onde suas condiÃÃes de extraÃÃo apresentam nÃveis crÃticos de tensÃo e um alto potencial corrosivo. Um dos grandes desafios do setor à assegurar as propriedades de juntas submarinas de aÃos soldadas quanto à resistÃncia mecÃnica, tenacidade e dureza, onde as mesmas, expostas a proteÃÃo catÃdica, podem sofrer fragilizaÃÃo por hidrogÃnio. Com o objetivo de evitar a necessidade de tratamento tÃrmico pÃs-soldagem no amanteigamento das juntas, uma alternativa à o emprego da tÃcnica dupla camada, a qual por meio da relaÃÃo adequada de energia de soldagem da primeira e segunda camada, visa-se obter o revenimento e o refino da estrutura com a sobreposiÃÃo de ciclos tÃrmicos. Para selecionar os parÃmetros utilizados nas camadas foram realizados os Testes Higuchi, depositando a liga de nÃquel UNS N06625 no aÃo baixa liga alta resistÃncia AISI 8630M com o processo de soldagem plasma com arco transferido, empregando material de adiÃÃo na forma de pà (PTA). As soldagens foram realizadas variando-se a energia de soldagem, a tÃcnica de soldagem e o gÃs de proteÃÃo. A partir das extensÃes de zona dura (ZD), zona macia (ZM), regiÃo grÃo grosso (ZACGG) e regiÃo grÃo fino (ZACGF) da zona afetada pelo calor obtidas com realizaÃÃo de perfis de microdureza e microscopia Ãtica, foi encontrada uma melhor relaÃÃo de energia, que promovesse o revenimento e o refino da microestrutura da ZAC. Juntas dos aÃos AISI 8630M e ASTM A182 F22 foram amanteigadas com as relaÃÃes de energia obtidas utilizando o processo PTA e enchidas utilizando o processo MIG. Nas interfaces dissimilares geradas entre os aÃos baixa liga alta resistÃncia e a liga de nÃquel UNS N06625 do amanteigamento foi realizada caracterizaÃÃo microestrutural e suas propriedades mecÃnicas foram medidas com a realizaÃÃo de microdureza, dureza e ensaio de fratura, visando avaliar a eficiÃncia dos Testes Higuchi. TambÃm foram analisadas a interface gerada entre a liga de nÃquel na forma de pà (amanteigamento) e na forma de arame (enchimento da junta) com microscopia Ãtica e dureza. As juntas amanteigadas na condiÃÃo indicada pelos testes Higuchi apresentaram um intenso refino na ZAC do aÃo baixa liga. A interface dissimilar apresentou uma composiÃÃo quÃmica intermediÃria entre os aÃos utilizados e a liga de nÃquel. A zona afetada pelo calor (ZAC) das amostras amanteigadas apresentaram uma diminuiÃÃo nos valores de dureza, no entanto para ambos os aÃos esses valores foram superiores aos estabelecidos pelas normas que regem a sua aplicaÃÃo. Os ensaios de fratura indicam que o fator de intensidade de tensÃo (K) encontrado para as amostras amanteigadas foram condizentes com a literatura.
Much of the domestic oil is located offshore environment where their extraction conditions have critical levels of strain and a high corrosion potential. One of the major challenges the sector is to ensure the properties of underwater joints welded steel as the mechanical strength, toughness and hardness, where the same exposed to cathodic protection can suffer hydrogen embrittlement. With the aim of avoiding the need for post-welding heat treatment of the buttering joints, an alternative is the use of double layer technique, which by means of suitable welding power ratio of the first and second layer, the aim is to obtain the tempering and refining structure with overlapping thermal cycles. To select the parameters used in the tests Higuchi layers were carried out by depositing nickel alloy UNS N06625 in high strength low alloy steel AISI 8630M with the process of welding plasma transferred arc, employing filler metal in powder form (PTA). The weldments were performed varying the welding energy, the welding technique and the shielding gas. From extensions harsh zone (HZ), soft zone (SZ), rough grain region (HAZRG) and fine grain region (HAZFG) of the heat affected zone obtained by performing microhardness and optical microscopy, better energy ratio was found, which promotes tempering and refining the microstructure of HAZ. Joints of AISI 8630M and ASTM A182 F22 were buttery with energy ratios obtained using the PTA process and filled using the MIG process. In the dissimilar interfaces generated between the low alloy high strength steels and nickel alloy UNS N06625 buttering the microstructural characterization was performed, and their mechanical properties were measured by carrying out hardness, hardness and fracture test, to evaluate the efficiency of tests Higuchi. The generated interface between the nickel alloy in powder form (buttering) and in the form of wire (joint filler) were anayzed using optical microscopy and hardness tests. The buttery joints in the condition indicated by Higuchi tests showed an intense refining HAZ of the low alloy steel. The dissimilar interface had a chemical composition intermediate between the steel used and nickel alloy. The heat affected zone (HAZ) of buttery showed a decrease in hardness, however for both steels these values of hardness test were higher than those established by the rules governing its application. The fracture test indicate that the fracture stress intensity factor (K) found for the buttery samples were consistent with the literature.
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SILVA, L. R. R. "Estudo do Desgaste por Erosão a Quente de Revestimentos WC-Cr-Co." Universidade Federal do Espírito Santo, 2013. http://repositorio.ufes.br/handle/10/4202.
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Previous issue date: 2013-10-30Este trabalho estuda o comportamento da erosão causada pelo impacto de partículas sólidas em revestimentos WC-Cr-Co, depositados pelos processos de Plasma Transferred Arc Powder (PTAP) e manta sinterizada. Esses revestimentos cobriram componentes sujeitos a desgaste erosivo, pois contêm fases duras distribuídas em uma matriz dúctil. Os ensaios ocorreram no erosímetro do Laboratório de Tribologia, Corrosão e Materiais (TRICORRMAT) da Universidade Federal do Espírito Santo (UFES) em três diferentes condições: na primeira, a partícula abrasiva utilizada foi alumina com um ângulo de incidência de 90°, em temperatura ambiente; na segunda e terceira, ensaiadas em temperatura elevada de 375ºC, houve utilização da hematita como abrasivo, sendo a variável o ângulo de impacto, consistindo em 90º e 30º, respectivamente. Nas três condições estudadas, a velocidade de impacto foi de 70 m/s, e o fluxo de partículas impactando a amostra dos ensaios seguiu a norma ASTM G 76. As microestruturas geradas pelos processos de deposição influenciaram diretamente a taxa de desgaste. Para a primeira condição, todos os materiais apresentaram microtrincamento no carboneto e microssulcamento e microcorte no ligante, o que foi devido à dureza do abrasivo alumina. Já para a segunda e terceira condições, nas quais os ensaios ocorreram com partículas abrasivas de hematita, houve redução do número de microtrincas presentes nos carbonetos e o desgaste da fase ligante ao redor do carboneto, contribuindo nos dois principais mecanismos de perda de massa. Nos ângulos rasos, observou-se que o desgaste do ligante na direção de impacto do abrasivo havia arrancado os carbonetos. Nos ensaios com hematita a 375ºC, o processo de revestimento por manta sinterizada proporcionou resistência ao desgaste quatro vezes maior, aproximadamente, que os revestimentos depositados por soldagem PTAP, independentemente do ângulo de impacto. Procedeu-se à caracterização das partículas abrasivas e das amostras por meio de microscopia eletrônica de varredura e micrografia qualitativa. Houve macro e microdureza das amostras relacionando-as com o comportamento em erosão. Palavras-chave: revestimento WC-Cr-Co, soldagem PTAP, manta sinterizada, erosão por partículas sólidas, abrasivo.
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BRAGANCA, B. C. "Comportamento em Desgaste Erosivo de Revestimentos Wc-cr-co Depositados Via Processos de Soldagem Pta-p e Por Manta Sinterizada." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/9811.
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Previous issue date: 2016-04-18Este trabalho estuda o comportamento em desgaste erosivo, causado pelo impacto de partículas sólidas, de revestimentos WC-Co-Cr depositados pelos processos de soldagem PTAP (Plasma Transferred Arc Powder) e manta sinterizada. O revestimento trata-se de um compósito cermet, em que a fase dura é coberta por carboneto de tungstênio (WC) e a fase ligante coberta por cromo (Cr) e cobalto (Co). Os ensaios foram realizados em erosímetro a jato de ar, com velocidade de impacto de 70 m/s e taxa de partículas de 2 mg/mm².s. Partículas de alumina e hematita foram utilizadas nos ensaios. Duas temperaturas de ensaio (23°C e 375 °C) e dois ângulos de impacto (30° e 90°) variavam as condições de ensaio. Os resultados indicaram que as microestruturas geradas nos processos de deposição influenciam fortemente na taxa de erosão. A fração volumétrica e o livre caminho médio de carbonetos, além da microdureza destes, são os principais parâmetros microestruturais que afetam a taxa de erosão. Também, devido ao processo de deposição, a influência de cada um dos parâmetros estudados (temperatura do ensaio, dureza da partícula e ângulo de impacto) pode ter maior ou menor influência no desgaste erosivo. Palavras chave: WC-Co-Cr; Erosão por partículas sólidas; Soldagem PTA-P; manta sinterizada.
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Schwessinger, Benjamin. "Genetic analysis of signalling components of PAMP-triggered immunity (PTI) in plants." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/25632/.
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FLORES, ALAMO NICOLAS 208394, and ALAMO NICOLAS FLORES. "Modelación de la PTAR “dulces nombres” : características hidráulicas de los reactores y modelación de la sedimentación." Tesis de maestría, Universidad Autónoma del Estado de México, 2008. http://hdl.handle.net/20.500.11799/94533.
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El número de plantas de tratamiento de aguas residuales (PTARs) con que cuenta la ciudad de Monterrey, México, les ha permitido el tratamiento del 100% de sus aguas residuales. Entre ellas, destaca la planta “Dulces Nombres” con una capacidad nominal de 18,000 m3/h, operada por el Servicio de Agua y Drenaje de Monterrey (SADM).
Los objetivos del presente trabajo fueron determinar el modelo hidráulico y de sedimentación de la PTAR “Dulces Nombres” de Monterrey, esto, a partir de pruebas de trazador y de sedimentación en columna.
Sin duda la modelación de la parte biológica del proceso de lodos activados es de suma importancia, sin embargo, para que un modelo de una PTAR este completo, es necesario establecer la plataforma de operación del modelo biológico, es decir, establecer el modelo hidráulico que mejor describa el funcionamiento de la PTAR. Para determinar el modelo hidráulico, se realizaron dos pruebas de trazador (rodamina WT), una en el reactor 1 y otra en el reactor 5, la cantidad de trazador (8 litros) agregado y el programa de muestreo fueron determinados mediante una presimulación en el simulador AQUASIM. A partir de los datos de concentración de rodamina WT obtenidos experimentalmente y el uso de AQUASIM, se logró determinar un modelo de 4 tanques de mezcla completa en serie, con un volumen de 4,780 m3, que describen el funcionamiento hidráulico de los reactores bajo estudio. Para validar el modelo obtenido fue necesario implementar otros modelos en AQUASIM con diferente número de tanques de mezcla completa en serie, que fueron desde 2, 3, 5 y 7 tanques.
La sedimentación secundaria juega un papel muy importante en buen funcionamiento del proceso de lodos activados. Para diseñar un sistema de sedimentación secundaria eficiente, es necesario determinar la velocidad de sedimentación del lodo. Los tres modelos de velocidad de sedimentación más utilizados son: el de Vesilind, Cho y Takács, siendo el primero de estos tres el más utilizado en la modelación debido a su simplicidad y a los buenos resultados que se han obtenido con este modelo. En el presente trabajo, se determinaron los parámetros de ajuste de los tres modelos, realizándose 5 corridas de sedimentación para cada uno de los sedimentadores bajo estudio. Para cada corrida se generaron 6 curvas de velocidad de sedimentación, cada prueba tuvo una duración de 35 minutos y el intervalo de concentración en que se realizaron las pruebas fue de 2 a 12 g/L de SST aproximadamente. Los parámetros n (0.36 m3/kg) y Vo (9.68 m/h) obtenidos para el modelo de Vesilind, permitieron obtener coeficientes de determinación, R2, para cada corrida en el intervalo de 0.96 a 0.99, lo que permitió establecer que el modelo de Vesilind se ajusta bien a los datos experimentales de velocidad de sedimentación. El análisis de sensibilidad para el modelo de Vesilind permitió determinar que los parámetros n y Vo obtenidos son identificables como valores únicos.
Se realizó un análisis de punto de estado con el que se estableció que la alta concentración promedio de sólidos suspendidos totales (5.1 g/L), con que operaba la PTAR “Dulces Nombres”, la pone en un alto riesgo de pérdidas de biomasa por arrastre, lo cual implica una disminución en la calidad del efluente. Las condiciones óptimas de operación encontradas, consistieron en mantener el caudal de recirculación medido (Q_rec) (2462.4 y 2286.6 m3/h reactor 1 y 5, respectivamente) y reducir la concentración de SST en los reactores mediante la manipulación del caudal de purga y recirculación de lodos hasta la concentración de diseño de 3.8 g/L. Esto permitiría operar con cargas hidráulicas de hasta el doble de Q_rec para ambos reactores y aun así operar sin riesgo de arrastre o pérdida de lodo.
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Chauca, Solgorré Michelly. "Análisis de ciclo de vida de una planta de tratamiento de aguas residuales (PTAR) en Lima." Civilizate, 2016. http://repositorio.pucp.edu.pe/index/handle/123456789/114630.
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El presente proyecto busca analizar la viabilidad medioambiental de la implementación de las etapas de tratamiento faltantes en la planta de tratamiento de aguas residuales (PTAR) Taboada. El estudio se realizará empleando la herramienta Análisis de Ciclo de Vida (ACV). El objetivo es comparar el impacto ambiental relacionado al ciclo de vida de la actual PTAR Taboada con unaplanta de procesos de tratamiento más avanzados. Cabe resaltar que la actual planta solo cuenta con la infraestructura necesaria para realizar un pretratamiento y tratamiento primario, cuando una planta avanzada posee adicionalmente los procesos secundario y terciario.
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Silva, Marcelo José de Oliveira. "Ânodos baseados em PtBi/C e PtPb/C para oxidação de ácido fórmico : um estudo comparativo." reponame:Repositório Institucional da UFABC, 2013.
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Chattot, Raphaël. "Surface Distortion and Electrocatalysis : Structure-Activity Relationships for the Oxygen Reduction Reaction on PtNi/C Nanocatalysts." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI093/document.
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Cette thèse a été initialement motivée par la compréhension de l’activité électrocatalytique particulière de particules PtNi/C creuses pour l’electroréduction du dioxygène (ORR). L’étude des mécanismes de formation et croissance de ces particules creuses, grâce à des techniques operando basées sur l’interaction rayons X- et/ou électrons-matière, a permis de montrer que les défauts cristallins améliorent les propriétés électrocatalytiques de nanomatériaux bimétalliques pour l’ORR. Le concept de « catalyseur défectueux » a pu être progressivement étendu à d’autres nanostructures PtNi, notamment des nanocatalyseurs à forme contrôlée, grâce à de fructueuses collaborations avec d’autres laboratoires européens. Ce travail montre, qu’en raison de la distorsion de leur surface, les nanomatériaux défectueux présentent des propriétés de chimisorption uniques, définissant ainsi une nouvelle classe de catalyseurs prometteurs et stablesThis PhD thesis was initially motivated by the understanding of the peculiar electrocatalytic activity of hollow PtNi/C nanoparticles for the oxygen reduction reaction (ORR). Investigations on the formation and growth mechanism of this novel class of nanocatalysts using operando X-ray and electron-based techniques revealed that, beyond alloying effects, structural disorder is a lever to boost the ORR kinetics on bimetallic nanomaterials. The ‘defects do catalysis’ concept was progressively extended to various PtNi catalyst nanostructures, namely to advanced shape-controlled nanocatalysts from the ORR electrocatalysis landscape thanks to fruitful collaborations with European laboratories. This work shows that, through their distorted surface, microstrained nanomaterials feature unprecedented adsorption chemisorption properties and represent a viable approach to sustainably enhance the ORR activity
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Krusemark, Thomas Wayne. "Service-Disabled Veteran-Owned Small Business Perceptions of Subcontracting Training Within the Department of Defense." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7548.
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Veteran-owned small businesses that possess ratings as service-disabled companies (i.e., service-disabled, veteran-owned small businesses [SDVOSB] are 1 of 5 socioeconomic small business contracting goals that U.S. government agencies seek to comply with U.S. Small Business Administration (SBA) set-aside goals. Little is known about collaborative strategies for improving training regarding single point of entry into Department of Defense (DOD) subcontracting. The research questions in this study focus on how veteran-owned small businesses pursue acquisition opportunities from training opportunities. Sabatier's advocacy coalition theory was used as the theoretical foundation for this study. This qualitative study was employed using 6 semistructured interviews of small business owners who possessed SDVOSB status and a content analysis of training policies from corporate supplier diversity offices, procurement assistance centers, small business development centers, and DOD Office of Small Business programs from a midwestern city. The emergent themes were (a) availability of training from procurement support assistance agencies is of limited value to mature small businesses; (b) additional support and training are needed for subcontractors desiring to enter the DOD subcontracting market; (c) significant obstacles are present in gaining access to federal subcontracting opportunities, including complex acquisition strategies and selection of contract type; and (d) understanding and enforcement of SDVOSB regulations were perceived as insufficient. SDVOSB entities can use these findings to comprehend what questions to ask about subcontracting training.
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Sjöström, Jenny. "Regulation of Plant Defense Genes Against Bacterial Pathogens." Thesis, KTH, Proteinvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293983.
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Sjukdom på grödor orsakad av bakterier kan bidra till ekonomiska förluster för bönder samt brist på mat, därför är det viktigt att utveckla nya hållbara sätt att motverka och behandla grödor mot bakterier. Idag är det mest vanliga tillvägagångssättet antibiotika men detta är inte hållbart p.g.a uppkomst av antibiotikaresistens. Antibiotika är inte heller tillgängligt för alla bönder och grödor då kostnaden blir för hög. Världsbefolkningen växer och om 80 år beräknas det bo mellan 9.9 och 12.7 biljoner (95% konfidens) människor på jorden. Växande befolkning samt ökande klimatförändringar, som torka och höjda temperaturer kräver nya bekämpningsmetoder mot bakterier för att tillgodose behoven i framtiden. Det saknas information om hur växter hanterar och reglerar bakteriella hot, därför är målet med denna studie att bidra med kunskap kring den transkriptionella regleringen av växters immunsystem mot bakterier. För att göra detta har promotorsekvenser hos gener som är förknippade med immunförsvaret i växter undersökts efter konserverade regulatoriska element. En känd receptor, FLS2 har en stor roll i växters försvar mot bakterier och känner igen en peptid från bakteriers flagell. Denna studie har undersökt FLS2 och den sammankopplade receptorn SERK1. Hos FLS2 kunde ingen konserverad modul hittas i uppströmsekvensen, däremot observerades ett 8 bp långt motiv, CAACTTG, i alla undersökta arter. I SERK1 hittades en lång konserverad modul bestående av flera motiv. Både FLS2-motifet och två motiv i SERK1-modulen binds av transkriptionsfaktorn MYC2. För att testa hypotesen att MYC2 bidrar till den transkriptionella regleringen av FLS2 och SERK1 har en experimentell plan utformats, där Nicotiana benthamiana transfekteras av Agrobacterium tumefaciens innehållandes promotorsekvenserna samt generna till transkriptionsfaktorn MYC2. En ökad förståelse kring de olika delarna och mekanismerna som medverkar inom växters immunförsvar kan bidra till den fortsatta forskningen mot hållbara lösningar till att säkra mat i framtiden.Several factors contribute to the demand of new, sustainable solutions to bring food security to the world population. The United Nations predicts, with a confidence of 95%, that the world population will be between 9.9 and 12.7 billion by year 2100. At the same time plant agriculture as seen today is threatened by climate changes e.g., rising temperatures and more extreme weather conditions. In addition, plant bacterial pathogens reduce yields, and cause losses of over $1 billion dollars worldwide every year to the food production chain. The currently most used and effective treatment against bacterial infections on crops is antibiotics, but this is not a viable alternative for most growers due to increasing antibiotic resistance and the high development, production, and distribution cost. During the upcoming years development of new approaches against bacterial infections on crops is of high importance but currently there are information gaps in the field of plant defense regulation systems. This study was aimed to provide knowledge about the transcriptional regulation of genes that are included in plant immune system towards bacteria. To investigate this, conserved regulatory elements of the upstream sequences of two defense-related plant receptor kinases, FLS2 and SERK1, was searched for in different species. FLS2 is a surface receptor that recognizes a peptide derived from the bacterial flagellin protein, and is part of the pathogen-triggered immunity response of most of higher plants. In FLS2 no conserved module was found but a single motif, CAACTTG, is conserved in all chosen species. In SERK1 a strikingly long and conserved module was found. Both the FLS2 motif and two motifs in the SERK1 module are recognition motifs with MYC2, a transcription factor involved in different plant mechanisms and the regulation of phytohormones like abscisic acid and auxin. To address whether MYC2 is involved in the transcriptional regulation of FLS2, an experimental approach is described, involving transactivation by MYC2 of FLS2 reporter constructs, studies using agroinfiltration in Nicotiana benthamiana. An increased knowledge about the different components and mechanisms of plant defense regulation will help the research towards new bactericides, transgenic plants, and other ways to secure food for upcoming generations.
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Collado, González Diego Andrés. "Generación de un Plan de Acción para el PTI Salmón Aysén de la XI Región para enfrentar la expansión de la industria." Tesis, Universidad de Chile, 2007. http://repositorio.uchile.cl/handle/2250/104780.
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La presente memoria tiene como objetivo generar un Plan de Acción que sería utilizado el próximo año 2008 en el inicio de las actividades de diseño y planificación del Programa Territorial Integrado Salmón Aysén (PTISA), instrumento de fomento de la Corporación de Fomento de la Producción (CORFO)
Cabe destacar que esta memoria se realizó en el marco del "Estudio de caracterización y determinación del potencial de atracción de inversiones del sector salmón en la XI Región" y del "Estudio para la determinación de la Línea Base de la Industria del Salmón en la XI Región de Aysén", trabajo que la empresa Knowledge Management Technology (KMT Consultores) realizó por encargo de CORFO, y en los cuales el autor de esta memoria fue miembro del equipo de trabajo.
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Wittern, Hanna Lena [Verfasser], and Horst [Akademischer Betreuer] Weller. "Investigation into PtNi Nanoparticles as Electrocatalyst for the Methanol Oxidation Reaction / Hanna Lena Wittern. Betreuer: Horst Weller." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://d-nb.info/1076866638/34.
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Makarova, Anna A., Elena V. Grachova, Dorota Niedzialek, Anastasia I. Solomatina, Simon Sonntag, Alexander V. Fedorov, Oleg Yu Vilkov, et al. "A curious interplay in the films of N-heterocyclic carbene PtII complexes upon deposition of alkali metals." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-215966.
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The recently synthesized series of PtII complexes containing cyclometallating (phenylpyridine or benzoquinoline) and N-heterocyclic carbene ligands possess intriguing structures, topologies, and light emitting properties. Here, we report curious physicochemical interactions between in situ PVD-grown films of a typical representative of the aforementioned PtII complex compounds and Li, Na, K and Cs atoms. Based on a combination of detailed core-level photoelectron spectroscopy and quantum-chemical calculations at the density functional theory level, we found that the deposition of alkali atoms onto the molecular film leads to unusual redistribution of electron density: essential modification of nitrogen sites, reduction of the coordination PtII centre to Pt0 and decrease of electron density on the bromine atoms. A possible explanation for this is formation of a supramolecular system "Pt complex-alkali metal ion"; the latter is supported by restoration of the system to the initial state upon subsequent oxygen treatment. The discovered properties highlight a considerable potential of the PtII complexes for a variety of biomedical, sensing, chemical, and electronic applications.