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PREPARING STUDENTS OF SCIENTIFIC AND TECHNICAL DEGREES FOR THEIR FUTURE
PROFESSIONAL CAREERS
E. Laguna-Gutierrez, B. Notario, J. Pinto, M. A. Rodriguez-Perez
CellMat Laboratory, Condensed Matter Physics Department, University of Valladolid (SPAIN)
ABSTRACT
After finishing their scientific and technical degrees, the professional development of the
students is mainly continued towards two different directions. On the one hand, an academic
path by performing a PhD and on the other hand, the direct incorporation into the working
world. In both options some experience in the development of scientific and research activities
is required. Nevertheless, in general the scientific and technical studies (at least in Spain) do
not give enough relevance neither to practical learning nor to the preparation of the students
for their integration into their professional careers.
According to this problematic in the year 2000 it was decided to develop an innovative
program for laboratory practices. This program was included into the subject “Extension of
Solid State Physics (ESSP)”, taught during the last year of the Physics degree in the University
of Valladolid. One of the main goals of these laboratory practices was to introduce the
students into real Research and Development (R&D) activities. After finishing this subject the
students acquired an experience which helped them to decide which way to follow (the
academic or the industrial one). Moreover, the integration of the students into their
professional careers was easier since they were able to develop different new skills (handling
of different equipment, interpretation of results, teamwork, oral defense, etc.).
In this communication the implementation and development of these laboratory practices are
described, providing some examples of the topics addressed in the practices. Moreover, the
effectiveness of this initiative is analyzed taking into account the subsequent academic or
industrial progress of the students implied in this innovative program.
1. INTRODUCTION
University should prepare the students for their future careers and encourage them for a
constant personal development. In particular, Spanish regulations define the functions of the
University as follows [1]:
Creation, development, and transmission of science, technique, and culture.
Preparation to perform professional activities that require the application of scientific
knowledge and methods, or artistic creation.
Diffusion, valorization, and transference of knowledge for culture, life quality, and
economic development.
Diffusion of knowledge and culture through the university extension and formation
along lifetime.
Focusing on the second point, the students should be able to perform professional activities
that require the application of their knowledge. As an example, it would be expected that
students with a scientific or technical degree have experience in the development of scientific
and research activities.
Previously to the introduction of the new European Higher Education Area system (EHEA), the
objectives of a scientific degree as the Physics Degree, from the University of Valladolid, were
the following [2]:
The student should master both, the physical theories and the most common
numerical and mathematical methods.
The student should be able to develop a model to describe a process or a complex
situation which also allows the prediction of its future evolution.
The student should know the physical laws, their applications and their limitations.
To provide students with a broad ability to learn different topics: electronics,
materials, information technology, etc.
To familiarize students with laboratory work, the experimental techniques and the
experimental methods.
To fulfill the last objective, only 10 % of the mandatory credits were focused on an
experimental/laboratory practicum. Normally, in these practical subjects the students followed
a guide to obtain the expected results. These guided practices are useful in the first years of
the Physics degree, as a first contact of the students with the laboratory. However, if this
approach is kept during the whole degree, the students will not face real situations where they
should make their own decisions, as will happen in their professional future.
Taking into account the previously-explained deficiencies in the Physics curriculum, the,
Condensed Physics Matter Department, belonging to this university, decided to include
laboratory practices, focused on real problems, in two of their subjects: Material Physics and
Extension of Solid State Physics. In a previous work Pinto et al. [3] described the characteristics
of the laboratory practices belonging to the Material Physics subject, as well as the results
obtained with this new strategy.
After fifteen years of development, this program of laboratory practices has come to an end,
as with the new EHEA the subject Extension of Solid State Physics has been eliminated.
Therefore, now is a good time to analyze this subject and make an assessment of this initiative
and its effectiveness.
2. EXTENSION OF SOLID STATE PHYSICS: SUBJECT DESCRIPTION
ESSP was a subject taught during the last year of the Physics degree in the University of
Valladolid [4]. This was an eligible subject which also was the continuation of a mandatory
subject called “Solid State Physics (SEP)”. As ESSP was an eligible subject, there was more
freedom to design the subject contents and to test new learning methodologies, such as the
laboratory practices.
Moreover, as ESSP was taught during the last year of the degree, the students taking the
subject had already the previous theoretical knowledge necessary to perform the
experimental practices. Therefore, they only needed a minimum supervision and also they
were able to take decisions and define their work strategies. Furthermore, another advantage
of being a final-year subject was that the students had already defined their specialization and
therefore the lessons taught in the subject were really useful for their future careers.
The aims of ESSP were on the one hand, to extend the concepts seen in SEP including both,
current topics and topics with an industrial interest. On the other hand, ESSP also included an
innovative program for laboratory practices focused on the development of real R&D activities.
Therefore, this subject aimed to train good physicists and to provide them with different skills
which facilitated their integration into their professional careers.
The subject ESSP was divided in six different lessons which are listed in Table 1.
LESSON
DESCRIPTION
1
Optical Properties of Solids
2
Quantum Magnetism in Magnetic Insulators
3
Superconductivity
4
Low Dimensional Systems
5
Characterization Techniques in Condensed Matter Physics
6
Characterization Methods in Solid State Physics
Table 1. Lessons of the Extension of Solid State Physics subject.
The first four lessons were theoretical lessons focused on expanding the SEP subject. The
lessons five and six were related to the laboratory practicum program which is described, in
more detail, in the following section.
3. CHARACTERISTICS OF THE LABORATORY PRACTICUM PROGRAM
As was mentioned previously, the laboratory practicum program was divided into two
different lessons which are described below.
3.1 Characterization Techniques in Condensed Matter Physics
Before entering the laboratory, the students should attend to several sessions (of
approximately five hours) in which the fundaments and work methodology of the
experimental techniques that they would use during the laboratory session were explained.
The laboratory made available to the students a wide set of experimental techniques which
are listed in the following tables. Micro-structural (Table 2), mechanical (Table 3) and thermal
(Table 4) characterization techniques as well as production techniques (Table 5) were available
in the laboratory.
MICRO-STRUCTURAL CHARACTERIZATION TECHNIQUES
Metallographic Microscope, Zeiss
Scanning Electron Microscope, Mod. JSM 820, Jeol
Stereoscopic Zoom Microscopy, Mod. SMZ-U, Nikon
EDX Microanalysis, Mod. QX 200, Brucker
Fourier Transform Infrared Spectroscopy, Mod. Tensor 27, Bruker
Air Pycnometer, Mod. P1.86, EijKelKamp
Gas Pycnometer, Mod. AccuPyc II 1340, Micromeritics
Table 2. Micro-structural characterization techniques available for the students of ESSP.
MECHANICAL CHARACTERIZATION TECHNIQUES
Universal Testing Machine, Mod. 5.500R6025, INSTRON
Dynamic mechanical analyzer, Mod DMA-861e, Mettler
Shore A and D Durometer, Mod. U/72, Bareiss
Vickers Microdurometer, Mod. MHO IB, Zeiss
Table 3. Mechanical characterization techniques available for the students of ESSP.
THERMAL CHARACTERIZATION TECHNIQUES
Melt Flow Index equipment, Mod. 3A, RAY-RAN
Calorimetric Bomb, Mod. 1341EE, Parr
Thermal conductivimeter, Mod. HDMD, Hotdisk
Thermogravimeter Analyzer, Mod. TGA/SDTA 861, Mettler
Differential Scanning Calorimetry, Mod. DSC 862, Mettler
Table 4. Thermal characterization techniques available for the students of ESSP.
PRODUCTION TECHNIQUES
Bench-top Co-rotating Twin-screw Extruder, Mod. ZK 25 T, Dr. Collin
Rheodrive, Mod. 5000, Haake
Micro-injection Moulding Machine, Mod. 6/10P, BabyPlast
Hot/cold plates Press, Talleres Remtex
Mixing Machine, Mod. T 25 Digital Ultra Turrax , IKA
Ultrasound Dispersive Tip, Mod. Vc-750, Sonics Vibra Cell
Electric Muffle Furnace, Mod. Select-Horn, P-Selecta
High Temperature Oven, Mod. 2001405, P-Selecta
Vacuum Drying Oven, Mod. VacioTem TV, P-Selecta
Vertical Tube Furnace, Mod. 100/250/1000, C.H.E.S.A.
High-temperature Oven (modified with sight windows), Mod.
Table 5. Production techniques available for the students of ESSP.
Furthermore, in this lesson the students also performed a bibliographic search related to their
laboratory practice. Through this initial search, the students became familiar with the topics
connected with their own research, which was very useful to perform both, the experimental
work in the lab and the final document including the results obtained during this work.
3.2 Characterization Methods in Solid State Physics
3.2.1 Objectives of the laboratory practicum
The main objectives of this laboratory practicum were the following:
To allow the students to contact with real R&D activities and with experienced
researchers.
To allow the students to develop new skills useful for their future careers.
To allow the students to become familiar with the preparation of technical reports and
oral presentation.
To help students to decide their future, either in an academic path or a direct
incorporation to industry.
Moreover, during these experimental sections the students were also instructed about the
need to develop the following skills:
Team work ability.
Self-learning ability.
Use of foreign languages.
3.2.2 Scheduling and organization of the laboratory practicum
Students were divided in groups of two people. They were always under the supervision of an
experienced researcher of the laboratory (tutor). The topic for each group was selected taking
into account the experience of the tutor.
The number of hours dedicated to this experimental research work was twenty five. Five of
these twenty five hours were dedicated to the explanation of the experimental techniques
(see section 2).
3.2.3 Practicum subjects
Different topics were considered to perform the experimental research. Over the years,
research works focused on superconductivity, metallurgy, foams, plastics, thermal treatments,
etc., have been developed by the students of ESSP. Examples of practicum topics carried out in
the last years are listed in Table 6.
EXPERIMENTAL WORK TITTLE
Thermal treatments of steel
Single-crystal growth by the Czochralski and solution methods
Thermal conductivity of polymeric foams
Optoelectronic characterization of GaAs on Si
Characterization of superconductors
Physical properties of PVC foams
Thermal treatments in brasses and bronzes
Thermal treatments of aluminium alloys
Physical characterization of polymeric foams
Electroluminescence
Packaging design using polymeric foams
Determination of the thermal conductivity of different materials
Mechanical characterization of polyolefin foams
Effect of the thermal treatments on the micro-structure and properties of LDPE
Table 6. Examples of practical topics carried out in the ESSP subject.
3.2.4 Contents of the final report and oral presentation
The development of both the final report and the oral presentation is as important as the
experimental research performed in the laboratory. For this reason, the student should
present the work twice. In the first meeting (mid-course) the students introduced the
objectives of their work, the experimental techniques selected and the first results obtained.
This presentation lasted 25 minutes. After this presentation both the teacher of the subject
and the laboratory tutor advised students so that they could continue with their work and also
asked them a series of questions related to their research. If the students did not answer
properly, they had another chance in the second meeting. Moreover, in this second meeting
(end of course) the students delivered the final report and they had 30 minutes to exhibit their
experimental work. After this presentation, relevant questions were asked.
The report and the presentation should follow the following scheme, which is the usual
scheme for the publications and presentations in this area.
1. Introduction
2. Materials
3. Experimental techniques
4. Results and discussion
5. Conclusions
6. Bibliography
The students got advice, from the tutor and the teacher, to perform the report and to prepare
the oral presentation. Moreover, the final presentation was recorded. In this way the students
could see their performance and analyze, with the teacher and tutor assistance, their failures
and how to improve the oral exposure.
3.2.5 Evaluation
The students evaluation was performed taking into account on the one hand, their theoretical
knowledge, through a written test, and on the other hand, their practical skills. The dedication
shown in the laboratory as well as the quality of both, the written report and the oral
presentation were the main parameters considered to evaluate the practical work. The final
mark combined the qualifications obtained in the exam and in the laboratory practice.
According to this, 50 % of the final mark of the subject was given by the laboratory practice.
3. EXAMPLE OF AN EXPERIMENTAL PRACTICE AND ITS DEVELOPMENT
In this section a description of a laboratory practice carried out in the year 2000 by students of
the subject ESSP is given. The title of this practice was: “Mechanical and Thermal Properties of
Polyvinyl Chloride (PVC) Foams”. Below, the objectives of the practice, the experimental
techniques employed and the results and conclusions obtained are summarized.
3.1 Objectives
The objectives of the practice were two:
To perform both, a microscopic and a macroscopic characterization (including thermal
and mechanical properties) of different PVC based foams:
- PVC + Polyurethane (PU) rigid foams
- Lineal PVC rigid foams
- PVC flexible foams
To fit the experimental data to theoretical models.
3.2 Experimental techniques employed
For the microscopic characterization the following techniques were employed:
Differential scanning calorimetry (DSC): To determine the thermal transitions of the
different materials.
Scanning electron microscopy (SEM): To analyze the cellular structure of the different
foams and determine the following parameters: cell size, cell wall thickness, cell
anisotropy and the mass fraction in the edges.
For the macroscopic characterization the following techniques were used:
Densimetry: To determine the density of the foamed materials.
Thermal conductivity: The thermal conductivity of the different materials was
determined by a stationary method.
Thermo-mechanical analysis (TMA): This analysis allows studying the changes
produced in the dimensions of the materials as a function of the temperature. From
this curve the linear expansion coefficient can be determined.
Dynamo-mechanical analysis (DMA): This analysis was performed to study the
viscoelastic behavior of the foamed materials (storage and loss moduli and loss
tangent). A throughout study of the viscoelastic behavior should be performed to
determine if the materials are suitable, or not, for certain applications.
3.3 Results
The students found the following results using the experimental techniques previously
described:
The glass transition temperature decreased when PU was added to the polymeric
matrix.
The cell size of the rigid foams was slightly higher than that of the flexible foams
(Figure 1).
There was a huge dependence between the parameters defining the cellular structure
(cell wall thickness, cell size and mass fraction in the edges) and the cellular materials
density.
In general, the thermal conductivity increased with the both, the temperature and the
density.
The foams with the lowest thermal conductivity were the Linear PVC rigid foams.
Therefore, they were the best materials for thermal insulation applications.
The thermal expansion coefficient remained constant with the temperature until the
glass transition temperature was reached. Moreover, for temperatures below the glass
transition temperature, this coefficient was also independent on the foam density.
For temperatures lower than the glass transition temperature, an increase in the
storage modulus with temperature was detected. However, for temperatures higher
than the glass transition temperature this modulus decreased with the temperature.
The experimental data, previously obtained, were fitted to a theoretical model to
determine the weight of the thermal conduction through the gaseous phase and the
solid phase and the weight of the thermal radiation in the thermal conductivity of the
foamed materials. It was determined that the heaviest term was that due to the
conduction through the gaseous phase.
Figure 1. SEM micrographs of the foamed materials. a) PVC + PU rigid foam. b) Linear PVC rigid foam. c)
PVC flexible foam.
3.4 Conclusions
From this experimental work it was concluded that a simple and systematic method was
employed to characterize the foamed materials and fit the experimental data to a theoretical
model in order to obtain the contributions of each of the mechanisms that take place in the
thermal conductivity of foamed materials.
4. CONCLUSIONS AND FUTURE PLAN
The professors of this subject consider that the development of this practical work in a real
R&D laboratory was essential to prepare the students for their future careers. The fact of
doing an experimental work similar to that performed by the PhD students and the laboratory
researchers, allowed students to develop new skills as well as to improve their Curriculum
Vitae including, for instance, experience in handling different experimental equipment.
Moreover, an important fact is that approximately 90 % of the students who have attended
the subject in the last five years are currently doing a PhD in fields related to the topics seen in
the subject. In this case most of the students chose the academic path. However, thanks to this
subject the students present higher aptitudes for the laboratory work and for the presentation
of their results, which are useful either for their PhD research or for an industrial work.
With the introduction of the new European Higher Education Area system (EHEA), the Degree
in Physics has been reduced from five to four years and therefore, some subjects have been
removed from the study program. ESSP is one of these removed subjects. However, taking into
account the previous results and the importance of this kind of subjects including experimental
works, it was decided not to eliminate this laboratory practicum. Therefore, a similar work to
that performed in ESSP is currently done in the subject of the new EHEA, “Final Year Project in
Physics Degree” [5].
4. ACKNOWLEDGEMENTS
Financial support from PIRTU contract of E. Laguna-Gutierrez by Junta of Castilla and Leon
(EDU/289/2011) and co-financed by the European Social Fund and financial support from FPI
grant BES-2013-062852 (B. Notario) from the Spanish Ministry of Education are gratefully
acknowledged.
a)
b)
c)
5. REFERENCES
[1] Ley Orgánica de Universidades (L.O.U.). 21 de diciembre de 2001. Spanish Government.
[2] www.uva.es
[3] J. Pinto, E. Solorzano, M. A. Rodriguez-Perez. The reality of industrial research applied to
experimental scientific studies. Proceeding EDULEARN 2014.
[4] Course syllabus of the subject “Extension of Solid State Physics”. University of Valladolid
[5] B. Notario, E. Laguna-Gutierrez, J. Pinto, M. A. Rodriguez-Perez. Final year project in
Physics´s degree: a new challenge for the scientific and technical training of students in their
last year of the Physic´s degree. Proceeding EDULEARN 2015.
