Brief interviews with scientists: Christian Polak (Vacuumschmelze GmbH & Co. KG, Germany).

Christian Polak
Christian Polak

Christian Polak first interacted with Vacuumschmelze GmbH & Co when his PhD thesis on amorphous materials, defended in the Technical University of Vienna (TU Wien), aroused the company´s interest. In 1993, he began working in the research and development area of the company, where he remains.

Vacuumschmelze started its activities about 100 years ago with the development of the first vacuum melting furnace (as suggested by its name in German) in the city of Hanau (Germany). Today, the company is a manufacturer of advanced magnetic materials and related products with more than 4,000 employees located in dozens of countries. These materials are present in the daily lives of millions of people, being part of cars, airplanes, elevators, solar and wind energy systems, transformers and more.

Rapid solidification technology.
Rapid solidification technology.

Currently, Dr Christian Polak heads the company’s Department for Rapid Solidification Technology. This process makes it possible to produce micrometric thick metal strips with superior magnetic properties by processing molten metal in only one step. Further processes can transform these amorphous materials into nanocrystalline alloys, whose grains are nanometric.

At the XVII B-MRS Meeting, Dr Polak will offer a plenary lecture on nanocrystalline magnetic materials and their applications, especially in the segment of miniaturized electronic devices.

See some information that Dr Polak provided related to the subject of his plenary lecture.

Nanocrystalline Magnetic Materials.

More than twenty years ago, Yoshizawa, Oguma and Yamauchi introduced a new class of iron-based alloys exhibiting superior soft magnetic behavior. The properties were a unique combination of the low losses, high permeability and near zero magnetostriction achieved by permalloys and Co-based amorphous alloys, but with a saturation magnetization up to 1.2 Tesla – much higher than either of these materials can conventionally offer. The particular about the new material is its ultrafine microstructure of b.c.c. Fe–Si with grain sizes of 10–15 nm from which their soft properties lastly derive. Based on this, this new class of alloys was named “nanocrystalline”. The material id compounded by crystallization of an amorphous Fe–Si–B alloy with small additions of Cu and Nb. This composition is the key for an ultrafine grain structure and the associated soft magnetic properties.

Nanocrystalline structure of VITROPERM material.
Nanocrystalline structure of VITROPERM material.

It is well known that the microstructure, noticeably the grain size, essentially determines the hysteresis loop of a ferromagnetic material. Nevertheless, we had to build up a deeper understanding of the coercivity (Hc) in the whole range of structural correlation lengths starting from atomic distances in amorphous alloys over grain sizes (D) in the nanometer regime up to macroscopic grain sizes. The 1/D-dependence of coercivity for large grain sizes reflects the conventional rule that good soft magnetic properties require very large grains (D>100μm). Thus, the reduction of particle size to the regime of the domain wall width increases the coercivity Hc. On the other hand lowest coercivities are again found for smallest structural correlation lengths like in amorphous alloys and in nanocrystalline alloys for grain sizes D<20nm. The new nanocrystalline material fills in the gap between amorphous metals and conventional poly-crystalline alloys. The combination of small grain size and soft magnetic properties is surprising and fascinating from the classical point of view in magnetic engineering.

Role of Nanocrystalline Soft Magnetic Materials in electronic devices and other applications.

The strip shaped soft magnetic amorphous and nanocrystalline material is used to produce so-called tape wound cores (=magnetic cores). Adding copper windings lead to well-known inductive components for electronic industry.

VACCUMSCHMELZE is the market and technology leader in many applications with years of experience in the international market. The company’s expertise covers the entire development process from knowledge of the characteristics of the alloy to fabrication technology and low cost manufacturing sites.

VAC produces inductive components based on nanocrystalline material for the installation, the automotive and the industrial market.

Examples for the installation market: Total current converters for earth fault current protection switches and current converters for electronic energy meters.

Examples for the automotive market: Chokes and transformers for the power management, flexible antennas for Keyless-Entry-Systems, for hybrid and electric vehicles: Recuperation-Systems, Start-Stop-Systems and DC/DC converters.

Examples for the industrial market: Chokes, transformers and power sensors for power supplies and rectifiers. Common mode chokes and nanocrystalline cores pave the way for compact innovative filter designs with highest efficiency for superior electrical motor drives according to newest international regulations. Gate drive transformers provide highest safety, excellent reliability and long lifetime for specialty (high voltage) applications combining efficiently energy- and signal- transmission in one component resulting in lower total costs. Current sensors offer maximum accuracy.

Newer Developments: High Frequency Applications (size reduction).

Tape wound cores: a nanocrystalline material application.
Tape wound cores: a nanocrystalline material application.

Vacuumschmelze is traditionally a supplier for inductive components. Conventional inductive components, like magnetic cores, inductive components, chokes and transformers, as well as flexible antennas are big and placed on top of PCB’s. All these established products are generally used in the lower frequency range, e.g. at 50Hz or up to some kHz.

Responding to future challenges for electronic circuits we have been faced with new requirements – especially there was a trend to use higher frequencies and consequently the trend for miniaturisation. This enables the use of embedded components where caps, semiconductors, resistors and inductances find a place inside of the PCB, respectively on one layer of a multilayer PCB.

To do first steps in this direction we take part in a joint research project called VISA, which was founded by the German Federal Ministry of Education and Research. Where we had to improve our amorphous or nanocrystalline soft magnetic materials in order to make them ready for high frequencies and embedding. Such inductive components should be flat, the maximum height should not exceed 1mm, the iron losses should be as low as possible and a high quality factor at switching frequency up to the MHz range was requested. For application, we were focused to DC/DC converters for the small power range. In addition, we expected applications for cores, planar inductors, shielding materials and sensors for automotive industry e.g. e-drive systems, for power LED technology or photovoltaic chargers or for shielding applications, like wireless charging systems.

Newer Developments: High Saturation Materials (size reduction).

Nanocrystalline Fe-Cu-Nb-Si-B alloys are well known to exhibit excellent soft magnetic properties (low coercivity flield Hand high permeability µ) combined with low magnetostriction (ls) and high saturation polarization around Js ~ 1.2T. They are meanwhile widely used in magnetic applications.

Since their discovery, a major driving force for further alloy development has been to increase the saturation polarization in order to receive a higher effective flux change after reversing the magnetic excitation. Thus, a higher inductance level could be achieved at simultaneously smaller volume. The most recent development are Fe-Si-B-P-Cu alloys which are reported to show high saturation polarization around J~ 1.8 T as well as reasonably low coercivity (Hc<10 A m).

One problem associated with these new alloys is that they are located near the glass-forming boundary, leading to serious production issues. Newer compositions investigated in the last years have been recently shown to exhibit sufficient glass forming ability for large-scale production. However, the saturation magnetostriction of nanocrystalline Fe-Si-B-P-Cu alloys is still relatively high (ls≈14 ppm). Low magnetostriction, however, is important for good soft magnetic properties and stress insensitivity of the hysteresis loop. The objective of current development is to investigate application capability of such alloy systems and to provide the so far missing behavior of magnetic properties, particularly in the nanocrystalline state.

Young B-MRS member receives 4 awards from international scientific societies in 2017.

Navadeep Shrivastava at the E-MRS Spring Meeting 2017 presenting the awarded poster.
Navadeep Shrivastava at the E-MRS Spring Meeting 2017 presenting the awarded poster.

So far this year, B-MRS member Navadeep Shrivastava has won four awards for his work on materials with magnetic and luminescent properties developed in the context of his doctoral research being conducted at the Federal University of Maranhão (UFMA) under the guidance of Professor Surender Kumar Sharma.

In February, Shrivastava was selected to receive a registration exemption at the E-MRS 2017 Spring Meeting, within an existing agreement between B-MRS and the European Materials Research Society (E-MRS). The award allowed the participation of the doctoratal student in the event, which was held in Strasbourg (France) from 22 to 26 May 2017.

At the E-MRS event, Shrivastava won an award for the poster he presented at the symposium entitled “Luminescence and Magnetic Behavior of Color Tuned LaF3:RE3+  (RE= Ce, Gd, Eu) Nanoparticles”. In addition, he presented another contribution at symposium V (“Green emitting magneto-luminescent iron-oxide/ZnS coated by codoped lanthanum fluoride nanomaterials”), which drew the attention of the audience, initiated a collaborative relationship with a group from the Université de Strasbourg (France) and expanded his network of professional contacts. “I want to express my gratitude for the opportunity to participate in the E-MRS 2017 Spring Meeting,” says Shrivastava.

In third place, the doctoral student was one of the winners of the 2017 Bernhard Gross Award, awarded by SBPMat to the best works presented by students at the annual events of the society. Shrivastava was awarded for the work “Facile synthesis and magneto-luminescence study of aliance of iron oxide and NaGdF4:RE3+ into nanoentity”, presented in an oral session at symposium B. The award was delivered on September 14 this year in the city of Gramado, during the closing ceremony of the XVI B-MRS Meeting.

Finally, the UFMA PhD student has just been selected to receive a travel assistance from the IEEE Magnetics Society to present two papers at the 62nd edition of the International Conference on Magnetism and Magnetic Materials, called MMM 2017, to be held in Pittsburgh in November of this year.

SBPMat´s community people: interview with Marcelo Knobel.

Marcelo Knobel. Credits: Antonio Scarpinetti – Ascom – Unicamp.

Scientific research, magnetic materials, scientific dissemination and higher education would be perhaps the biggest expressions in a cloud of tags to represent Professor Marcelo Knobel.

Born in Buenos Aires (Argentina) in 1968, Marcelo Knobel came to live in Brazil, more specifically in Campinas (SP), by the age of 8 years-old, following his parents, the psychologist Clara Freud de Knobel and the psychiatrist Maurício Knobel. The family was escaping from the coup d’etat that had just established in Argentina a military dictatorship that fired Maurício from the University of Buenos Aires (UBA). In Brazil, which was also governed by a military dictatorship, Maurício had been contracted for the State University of Campinas (Unicamp).

Ten years after the arrival in Campinas, Marcelo Knobel joined Unicamp to a graduation in Physics. In parallel to the studies, he started to do research on magnetic properties of materials. After he obtained the bachelor´s degree, Knobel remained in Unicamp for the doctorate in the same area, receiving the diploma of doctor in Physics when he defended his dissertation on magnetism and structure of nanocrystalline materials in 1992. After that, he went to Europe, where he conducted two postdoctoral internships; one at Istituto Elettrotecnico Nazionale Galileo Ferraris, Italy, and the other at the Instituto de Magnetismo Aplicado, Spain.

Returning to Brazil and to Unicamp, in 1995, Marcelo Knobel started his career of professor and researcher of the Institute of Physics Gleb Wataghin (IFGW). From 1999 to 2009 he was the coordinator of the Laboratory of Materials and Low Temperatures, where he acts as researcher until the present moment, always investigating magnetism and magnetic materials. Together with his collaborators of the laboratory, Knobel have carried pioneering works in the study of the giant magnetoresistance and magnetoimpedance in certain materials – two different concepts that are related to the opposition that a material offers to the passage of the electricity in consequence of the application of an external magnetic field. In 2008, Knobel became Full Professor of the Department of Condensed Matter Physics at IFGW.

In the area of scientific dissemination, Marcelo Knobel started in the year 2000 to perform education and research activities at the Laboratory of Advanced Studies in Journalism (LABJOR) of Unicamp. Moreover, Knobel was one of the creators of NanoAventura, an interactive and itinerary exposition on nanotechnology that started in 2005 and was visited by more than 50 thousand people, mainly children, until now. NanoAventura received honorable mentions at Scientific Cine and Video Festival of Mercosur (2006) and at Mercosur Science and Technology Award (2015), as well as an award in 2009, from the Latin American and Caribbean Network for the Popularization of Science and Technology (RedPOP). From 2006 to 2008, Knobel was the first director of the Exploratory Museum of Science, linked to Unicamp. In 2008, he became editor in chief of the magazine Ciência & Cultura of the Brazilian Society for the Progress of Science (SBPC), position that he occupies until now. In the publishing field, Knobel coordinates a collection of science dissemination books of the Unicamp Publisher, called Meio de Cultura, released in 2008.

In 2007 Marcelo Knobel received the Young Scientist Prize from the TWAS-ROLAC (office of Latin America and the Caribbean of the The World Academy of Sciences for the advancement of science in developing countries), an awars for young scientists of the region. In the same year, he was selected, together with about 50 people of different professional areas and several countries of the world, to participate of the program Eisenhower Fellowships, which aims to strengthen the leadership potential of its fellows. The group travelled for the United States during 7 weeks complying with a schedule of meetings and seminars. In 2009, he was chosen as a fellow of John Simon Guggenheim Memorial Foundation, receiving resources for research.

From 2009 to 2013, he was Vice-President for Undergraduate Programs of Unicamp. In this position, he was responsible for the implantation of the Interdisciplinary Program of Higher Education (ProFIS). ProFIS is a higher education course of 4 semesters that provides a general, multidisciplinary and critical formation, and makes possible to its alumni (former students of public schools chosen by their good grades in the Brazilian National Exam of the Secondary School (ENEM) that they enter graduation courses at Unicamp without passing for Brazilian admission university exam). The program was distinguished in 2013 with the Prize Péter Murányi – Education, destined to actions that increase well-being of populations of the south hemisphere.

In 2010, with 42 years-old, Knobel was honored with the title of Commendatore of the Order of the Scientific Merit by the Brazilian Presidency of the Republic.

Holder of a productivity scholarship 1A (the highest) at CNPq, Marcelo Knobel has published about 300 scientific articles in peer-review international journals and 15 chapters of books on magnetic materials and properties, popularization of science, public perception of science and higher education. Also he is the author of articles about science and education published in diverse medias. He has 6.370 citations, according to Google Scholar.

Marcelo Knobel had just assumed, in August 3rd, the position of director of the Brazilian National Laboratory of Nanotechnology (LNNano), of the National Center of Research in Energy and Materiais (CNPEM).

Here follows a brief interview with the scientist.

SBPMat newsletter: – Tell us what made you become a researcher and work in the field of Materials.

Marcelo Knobel: – I chose the area of Physics because of the curiosity, without knowing exactly what this meant. But already in the first semester I realized that it was what I wanted for my life, to try to understand the nature. Early in the beginning of the graduation, I had a laboratory class with professor Reiko Sato, who later invited me to do scientific initiation in her laboratory. She worked with magnetic properties of amorphous metals, and that was the subject of my research. Later, I went to the doctorate also with her, already working with nanocrystals, and later I followed the postdoctoral in the same area.

SBPMat newsletter: – Which are, in your own evaluation, your main contributions to the field of Materials?

Marcelo Knobel: – I am acting in nanoscopic magnetic systems, mainly investigating dipole interactions in magnetic nanosystems, using several experimental techniques, theoretical models and computational simulations. These systems, beyond the interest in basic research, have many possible applications, mainly in systems of magnetic record and nanomedicine. The research group that I helped to consolidate develops new nanocrystalline materials and carries studies through the development of new magnetic, structural and transport techniques. In the scope of these researches, we were pioneer in the study of giant magnetoresistance in granular systems and in the research of giant magnetoimpedance in amorphous and nanocrystalline wires and ribbons. But I have also been dedicating myself to scientific dissemination, being one of the responsible for the creation of the Exploratory Museum of Sciences of Unicamp.  I was the coordinator of NanoAventura project, which is an interactive and itinerary exhibit on nanoscience and nanotechnology for children and adolescents. I still work in research in the area of public perception of science, I coordinate the series “Meio de Cultura” of Unicamp Publisher and I act as an editor in chief of the magazine Ciência & Cultura, of SBPC. Recently, I was Vice-President for Undergraduate Programs of Unicamp, where I highlight the implantation of the Interdisciplinary Program of Higher Education (ProFIS). Currently, I am initiating a new challenge, as Director of the National Laboratory of Nanotechnology (LNNano).

SBPMat newsletter: – You have an especially strong performance in dissemination of science and scientific culture. Comment with our readers, students and researchers, which is, for you, the importance to carry through this type of activity.

Marcelo Knobel: – I became a scientist after reading books and magazines of dissemination and visiting museums of sciences. I believe that we must stimulate the new generations to think critically, to have curiosity, to search to unmask the mysteries that surround them. For Brazil it is basic to stimulate young talents for science. Without them we will not have a future… Moreover, it is our obligation to give account to the society, which is the financer of the scientific research in public universities and research institutes. It is important to show the science that is done in our country, and the importance to follow investing, more and more, in science and technology.

SBPMat newsletter: – If you want, you can leave a message for the readers that are initiating their scientific careers.

Marcelo Knobel: – I do not have doubts that it is the passion that must guide the careers of everybody, and mainly of the scientists. But beyond the passion, a solid formation is necessary, not only in the specific content, but also in personal abilities, as work in team, communication (including Portuguese and English, scientific writing) and general knowledge. The scientific activity demands effort and devotion, but we are rewarded, I guess, with a life full of new challenges and opportunities.

Entrevista com o professor Sergio Machado Rezende, vencedor do Prêmio FCW de Ciência.

Crédito: Leo Ramos.

O professor Sergio Machado Rezende, pesquisador da área de Física de Materiais e ex-gestor (como ele diz) de ciência e tecnologia, recebeu, na noite de 17 de junho deste ano, o Prêmio FCW de Ciência, da Fundação Conrado Wessel. Membro da comunidade brasileira de pesquisa em Materiais, Rezende teve importante participação na criação da nossa SBPMat.

O prêmio recebido por Rezende em cerimônia na Sala São Paulo reconhece perfis renomados em ciência, com qualidades de talento inovador, liderança, abrangência social, trabalho incansável, integridade e ética. Os candidatos são indicados por instituições reconhecidas do país. No caso de Rezende, a indicação partiu da Universidade Federal de Pernambuco (UFPE), onde ele é professor titular do Departamento de Física desde 1972.

Nascido no Rio de Janeiro, Sergio Rezende se formou em Engenharia Eletrônica em 1963 pela Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio) e obteve o mestrado e o doutorado, ambos em Engenharia Eletrônica-Ciência de Materiais, no Massachusetts Institute of Technology (MIT), nos Estados Unidos. De volta ao Brasil, e antes de entrar na UFPE, foi professor associado da Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio) e professor titular da Universidade Estadual de Campinas (Unicamp).

Em gestão de ciência e tecnologia, foi presidente da Finep entre 2003 e 2005 e ministro da Ciência e Tecnologia de 2005 a 2010. Antes de assumir a Presidência da Finep, ocupou os cargos de diretor científico da Fundação de Amparo à Ciência e Tecnologia de Pernambuco (Facepe); secretário de Ciência, Tecnologia e Meio Ambiente do Estado de Pernambuco, e secretário do Patrimônio, Ciência e Cultura da Prefeitura de Olinda, além de chefe do Departamento de Física e diretor do Centro de Ciências Exatas da UFPE.

Dentro da sua atuação acadêmica, desenvolvida quase sempre em paralelo à sua atuação como gestor público, o professor Rezende orientou 36 trabalhos de mestrado e de doutorado e publicou mais de 230 artigos científicos em revistas de circulação internacional.

Entre outras distinções, Sergio Rezende recebeu, em 1995, a Comenda da Ordem do Mérito Científico, categoria Grã-Cruz, por suas relevantes contribuições à ciência e tecnologia, e, em 2001, o Prêmio Anísio Teixeira da Capes, homenagem a personalidades brasileiras que tenham contribuído de modo relevante para o desenvolvimento da pesquisa e formação de recursos humanos no país. Rezende também foi distinguido, em 2011, com a primeira palestra memorial “Joaquim Costa Ribeiro”, honraria outorgada pela SBPMat.

Segue uma breve entrevista com o professor.

Boletim da SBPMat (B. SBPMat): – Quais são, na sua avaliação, as suas principais contribuições/ ações de maior impacto para a ciência no Brasil, seja no seu papel de pesquisador e formador de pessoas, seja no seu papel de gestor público?

Sergio Machado Rezende (S.M.R.): – Eu gostaria de destacar duas, uma como pesquisador e outra como gestor no cargo mais alto que ocupei.
A primeira foi o meu papel na implantação de um grupo de pesquisa em Física na Universidade Federal de Pernambuco, iniciada em 1972, num lugar onde não havia pesquisa em Física anteriormente. Eu fui o primeiro doutor na área de Física da universidade. Com meus colegas conseguimos formar um grupo que faz pesquisa na fronteira do conhecimento, temos ótimos laboratórios e estamos contribuindo na formação de engenheiros (Física básica) e formando bons físicos em nossos programas de graduação e pós-graduação. Isso mostra que é possível fazer no Brasil uma instituição de ensino e pesquisa de bom nível, num local sem tradição na área, desde que haja determinação, pessoas qualificadas e apoio do governo.
A segunda foi na minha atuação no Ministério da Ciência e Tecnologia, onde, com grande articulação da comunidade científica, empresarial e do governo, fizemos um plano de ação de ciência, tecnologia e inovação que foi bem sucedido, com prioridades claras, linhas de ação abrangentes e programas bem articulados, que possibilitaram grande aumento nos recursos financeiros federais e estaduais.

B.SBPMat: – Após muitos anos conciliando o trabalho de gestor público com o de professor e pesquisador, já de volta à vida de cientista em tempo integral, conte-nos um pouco sobre seus projetos e interesses atuais, principalmente os referentes à pesquisa em Materiais.

S.M.R.: – Eu praticamente sempre trabalhei com materiais magnéticos. Fiz poucos trabalhos que não envolveram materiais magnéticos. Nos últimos tempos tenho me dedicado a uma área do magnetismo que se chama spintrônica. É uma área muito nova, que está desenvolvendo rapidamente. Já tem algumas aplicações tecnológicas muito difundidas, mas tem um potencial de aplicações muito grande. A spintrônica ainda está numa fase inicial de desenvolvimento, então seus desafios científicos são muito interessantes e estão na fronteira do conhecimento. É muito estimulante para um cientista ter a possibilidade de trabalhar numa área que é competitiva, que tem muita gente trabalhando e que está crescendo rapidamente.

B.SBPMat: – O senhor sempre pesquisou materiais magnéticos e propriedades magnéticas. Qual é a sua apreciação da evolução dessa área e de seus principais desafios?

S.M.R.: – Os materiais magnéticos, como se sabe, têm muitas aplicações tecnológicas, e algumas delas são muito antigas. Desde que o motor elétrico, o gerador e os transformadores foram inventados no século XIX, a eletricidade passou a ser muito presente em nossa vida. Os materiais magnéticos são essenciais para todos eles, assim como para muitos outros dispositivos e equipamentos, divididos em duas classes bem distintas, os ímãs permanentes, que retêm sua magnetização, e os materiais moles, que são facilmente desmagnetizados. Existe uma terceira categoria de aplicações de materiais magnéticos que exige propriedades intermediárias entre os dois, é na gravação magnética, usada hoje principalmente nos discos rígidos dos computadores. Nessas três áreas de aplicações, são os resultados da pesquisa em Física, Química e Engenharia de Materiais que têm possibilitado o desenvolvimento de materiais melhores, com maior capacidade e em volumes menores.
Por exemplo, hoje os ímãs de terras raras que foram desenvolvidos nos últimos quinze a vinte anos são essenciais para se fazer motores e geradores de alta eficiência, empregados nos carros elétricos e nos geradores de turbinas eólicas. As turbinas eólicas, que são usadas para gerar energia a partir do vento, hoje têm capacidade de geração muito alta, graças em grande parte ao desenvolvimento de ímãs de terras raras.
Na área de gravação magnética, nós vemos a evolução em nosso dia-a-dia. A cada ano, a capacidade de memória do disco rígido dos novos computadores é maior. E nós queremos mais memória para armazenar mais informação. A grande evolução na capacidade de armazenamento dos computadores é resultado, exatamente, da pesquisa e desenvolvimento dos materiais magnéticos usados na gravação e também da cabeça de leitura da informação gravada. Todos os computadores atuais usam na cabeça de leitura um sensor de spintrônica, que utiliza um fenômeno chamado magneto-resistência gigante (GMR). É interessante lembrar que a GMR foi descoberta em 1989 por uma equipe da Universidade de Paris em Orsay, do qual fazia parte Mario Baibich, físico da UFRGS, que foi o primeiro autor do artigo científico que relatou a descoberta.

B.SBPMat: – Gostaria de deixar alguma mensagem para nossos leitores que estão iniciando suas carreiras de cientistas?

S.M.R.: – Há quarenta anos, quando eu vim para Pernambuco, os recursos para ciência eram muito menores do que são agora, o ambiente na universidade não favorecia muito a pesquisa, havia muito poucos pesquisadores, não havia programas de pós-graduação. Mas a situação mudou muito nos últimos quarenta anos. Então, o que eu quero dizer para o jovem que começa sua carreira atualmente é que dificuldades ainda existem, mas elas são hoje muito menores do que na época em que eu estava começando minha carreira. E que a coisa mais importante para um jovem é não desanimar. É preciso enfrentar os problemas com disposição. É preciso entender que o Brasil tem um futuro muito amplo e que a ciência e a tecnologia vão ser cada vez mais importantes para nosso desenvolvimento. O jovem precisa ter consciência de que vai ter um papel importante no futuro e precisa ter confiança para não desanimar com as dificuldades que, como disse antes, são muito menores hoje do que no passado.