Julian Gonzalez

Prof. Julian Gonzalez

Department of Materials Physics, University of the Basque Country, Barrio Sarriena, s/n, 48940 Leioa, BI, Spain

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 June 2025 in Batteries
Verified
Journal Article
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MHMohamed Salaheldeen Mohamed Hassan
Mohamed Salaheldeen Mohamed Hassan
TEThomas Nady A. Eskander
Thomas Nady A. Eskander
MFMaher Fathalla
Maher Fathalla
Valentina ZhukovaValentina Zhukova
Valentina Zhukova
JBJuan Mari Blanco
Juan Mari Blanco
Ahmed Abu-Dief MohammedAhmed Abu-Dief Mohammed
Ahmed Abu-Dief Mohammed
The accelerating global demand for sustainable and efficient energy storage has driven substantial interest in supercapacitor technology due to its superior power density, fast charge–discharge capability, and long cycle life. However, the low energy density of supercapacitors remains a key bottleneck, limiting their broader application. This review provides a comprehensive and focused overview of the latest breakthroughs in supercapacitor research, emphasizing strategies to overcome this limitation through advanced material engineering and device design. We explore cutting-edge developments in electrode materials, including carbon-based nanostructures, metal oxides, redox-active polymers, and emerging frameworks such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). These materials offer high surface area, tunable porosity, and enhanced conductivity, which collectively improve the electrochemical performance. Additionally, recent advances in electrolyte systems—ranging from aqueous to ionic liquids and organic electrolytes—are critically assessed for their role in expanding the operating voltage window and enhancing device stability. The review also highlights innovations in device architectures, such as hybrid, asymmetric, and flexible supercapacitor configurations, that contribute to the simultaneous improvement of energy and power densities. We identify persistent challenges in scaling up nanomaterial synthesis, maintaining long-term operational stability, and integrating materials into practical energy systems. By synthesizing these state-of-the-art advancements, this review outlines a roadmap for next-generation supercapacitors and presents novel perspectives on the synergistic integration of materials, electrolytes, and device engineering. These insights aim to guide future research toward realizing high-energy, high-efficiency, and scalable supercapacitor systems suitable for applications in electric vehicles, renewable energy storage, and next-generation portable electronics.

18 February 2016 in BMC Public Health
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MGMara Gallastegi
Mara Gallastegi
MGMonica Guxens
Monica Guxens
AJAna Jiménez-Zabala
Ana Jiménez-Zabala
ICIrene Calvente
Irene Calvente
MFMarta Fernández
Marta Fernández
LSLoreto Santa-Marina
Loreto Santa-Marina
Analysis of the association between exposure to electromagnetic fields of non-ionising radiation (EMF-NIR) and health in children and adolescents is hindered by the limited availability of data, mainly due to the difficulties on the exposure assessment. This study protocol describes the methodologies used for characterising exposure of children to EMF-NIR in the INMA (INfancia y Medio Ambiente- Environment and Childhood) Project, a prospective cohort study. Indirect (proximity to emission sources, questionnaires on sources use and geospatial propagation models) and direct methods (spot and fixed longer-term measurements and personal measurements) were conducted in order to assess exposure levels of study participants aged between 7 and 18 years old. The methodology used varies depending on the frequency of the EMF-NIR and the environment (homes, schools and parks). Questionnaires assessed the use of sources contributing both to Extremely Low Frequency (ELF) and Radiofrequency (RF) exposure levels. Geospatial propagation models (NISMap) are implemented and validated for environmental outdoor sources of RFs using spot measurements. Spot and fixed longer-term ELF and RF measurements were done in the environments where children spend most of the time. Moreover, personal measurements were taken in order to assess individual exposure to RF. The exposure data are used to explore their relationships with proximity and/or use of EMF-NIR sources. Characterisation of the EMF-NIR exposure by this combination of methods is intended to overcome problems encountered in other research. The assessment of exposure of INMA cohort children and adolescents living in different regions of Spain to the full frequency range of EMF-NIR extends the characterisation of environmental exposures in this cohort. Together with other data obtained in the project, on socioeconomic and family characteristics and development of the children and adolescents, this will enable to evaluate the complex interaction between health outcomes in children and adolescents and the various environmental factors that surround them.

28 April 2000 in Journal of Applied Physics
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Julian GonzalezJulian Gonzalez
Julian Gonzalez
Arcady ZhukovArcady Zhukov
Arcady Zhukov
JBJuan Maria Blanco
Juan Maria Blanco
ACAntxon F. Cobeño
Antxon F. Cobeño
MVManuel Vazquez
Manuel Vazquez
KKKrzysztof Kułakowski
Krzysztof Kułakowski
Measurements of the saturation magnetostriction λs of glass-coated covered (Co1−xMnx)75Si10B15 (x=0.09, 0.10 and 0.105) and Co56.5Fe6.5Ni10B16Si11 amorphous microwires carried out by means of the stress dependence of initial magnetic susceptibility method are reported. The conditions of applicability of this method to the microwires have been analyzed, taking into account the domain structure expected for very low negative magnetostriction of the metallic nucleus. The experimental data of λs obtained in those amorphous microwires are in agreement with those reported in amorphous ribbons with similar compositions.

20 August 2019 in Materials
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ATAhmed Talaat
Ahmed Talaat
Valentina ZhukovaValentina Zhukova
Valentina Zhukova
MIMihail Ipatov
Mihail Ipatov
JBJuan María Blanco
Juan María Blanco
Julian GonzalezJulian Gonzalez
Julian Gonzalez
Arcady ZhukovArcady Zhukov
Arcady Zhukov
The domain wall (DW) dynamics of amorphous and nanocrystalline Co-based glass-coated microwires are explored under the influence of stress annealing. Different annealing profiles have enabled remarkable changes in coercivity and magnetostriction values of Co-based amorphous microwires with initially negative magnitude, allowing induced magnetic bistability in stress-annealed samples and, consequently, high DW velocity has been observed. Similarly, Co-based nanocrystalline microwires with positive magnetostriction and spontaneous bistability have featured high DW velocity. Different values of tensile stresses applied during annealing have resulted in a redistribution of magnetoelastic anisotropy showing a decreasing trend in both DW velocities and coercivity of nanocrystalline samples. Observed results are discussed in terms of the stress dependence on magnetostriction and microstructural relaxation.

23 July 2022 in Chemosensors
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ACAlexander Chizhik
Alexander Chizhik
Julian GonzalezJulian Gonzalez
Julian Gonzalez
Arcady ZhukovArcady Zhukov
Arcady Zhukov
PGPrzemyslaw Gawronski
Przemyslaw Gawronski
We provide an overview of the helical magnetic structures in magnetic microwires. Having analyzed the experimental data describing the magnetic behavior of magnetic microwires since the 1990s, we found indirect evidence of the existence of various types of helical magnetic structures. Purposeful research has allowed us to discover the spiral magnetic structure as one of the most unusual helical structures. A comparison of the spiral structure with another type of helical structure—elliptical—was carried out. In the analysis, emphasis was placed on the length of the domain wall as one of the most important parameters. The difference in the dynamic properties of the spiral and elliptical domain walls has been demonstrated.

13 March 2023 in Sensors
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ACAlexander Chizhik
Alexander Chizhik
PCPaula Corte-Leon
Paula Corte-Leon
Valentina ZhukovaValentina Zhukova
Valentina Zhukova
Julian GonzalezJulian Gonzalez
Julian Gonzalez
PGPrzemyslaw Gawronski
Przemyslaw Gawronski
Arcady ZhukovArcady Zhukov
Arcady Zhukov
We studied the magnetic properties of a glass-covered amorphous microwire that was stress-annealed at temperatures distributed along the microwire length. The Sixtus-Tonks, Kerr effect microscopy and magnetic impedance techniques have been applied. There was a transformation of the magnetic structure across the zones subjected to annealing at different temperatures. The annealing temperature distribution induces the graded magnetic anisotropy in the studied sample. The variety of the surface domain structures depending on the longitudinal location has been discovered. Spiral, circular, curved, elliptic and longitudinal domain structures coexist and replace each other in the process of magnetization reversal. The analysis of the obtained results was carried out based on the calculations of the magnetic structure, assuming the distribution of internal stresses.