Παρουσίαση Μεταπτυχιακής Διπλωματικής Εργασίας της κ. Μαρίας Συσκάκη

25 Ιουνίου 2024

ΠΑΝΕΠΙΣΤΗΜΙΟ ΚΡΗΤΗΣ

ΤΜΗΜΑ ΕΠΙΣΤΗΜΗΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ ΥΛΙΚΩΝ

ΠΑΡΟΥΣΙΑΣΗ ΜΕΤΑΠΤΥΧΙΑΚΗΣ ΔΙΠΛΩΜΑΤΙΚΗΣ ΕΡΓΑΣΙΑΣ

Τίτλος

«Cs₂AgBiBr₆ Perovskites & 2D Material Conjugations for Gas Sensing Applications»  

της Μαρίας Συσκάκη

μεταπτυχιακής φοιτήτριας του Τμήματος Επιστήμης και Μηχανικής Υλικών του Πανεπιστημίου Κρήτης

 Επιβλέπων: Εμμανουήλ Στρατάκης

 Πέμπτη 27 Ιουνίου 2024, Ώρα 13:00

H παρουσίαση θα πραγματοποιηθεί στην αίθουσα Τηλε-εκπαίδευσης (Ε130), στο κτήριο του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών, του Πανεπιστημίου Κρήτης

Abstract

Gas sensors are devices capable of detecting the presence and concentration of various gases, playing a crucial role in applications such as air-quality monitoring, public safety, agriculture, and medical diagnosis. The most common sensing materials are metal oxide semiconductors, which have low-cost production and high sensitivity, albeit necessitate high temperatures or other external stimuli to operate. Therefore, there is need to develop new sensing materials that can overcome this limitation, while maintaining or offering better sensing performance. An alternative and promising candidate material for gas sensing is the group of all-inorganic metal halide perovskites, having the general formula ABX₃, where A is an organic or inorganic cation, B is a metal cation, and X is a halide anion. They have exhibited the ability to detect gases (O3 and H2) at very low concentrations (a few ppb), featuring fast response times (few hundreds of seconds) without the demand of external triggering. However, challenges persist, including environmental instability and toxicity of lead, commonly utilized as the metal cation. Taking into account the aforementioned properties and needs, this project aimed to fabricate lead-free double halide perovskite gas sensing elements (Cs₂AgBiBr₆) in the form of nano- or micro-crystals, employing a straightforward and room-temperature ligand-free precipitation method. Furthermore, the perovskites were conjugated with 2D graphene-based materials and Transition Metal Dichalcogenides (TMDs) to enhance their conductivity and their sensing ability. Diverse synthesis methods and characterization techniques were used to optimize the fabrication process and understand the sensing mechanisms of those novel materials. Cs2AgBiBr6 nanocrystals found to be capable of detecting low O3 concentrations down to 50 ppb, having response and recovery times around 1 minute.

Παρουσίαση της Διδακτορικής Διατριβής του κ. Κωνσταντίνου Λουκέλη

12 Ιουνίου 2024

Invitation to a Public Presentation of his Doctoral Thesis

Mr. Konstantinou Loukelis

Supervising Professor: Maria Chatzinikolaidou

(According to article 95, par. 3 of Law 4957/2022, Official Gazette 141 vol. A/21.7.2022)

On Wednesday, June 19, 2024 at 12:00 in the E-Learning room E130 of the Department of Mathematics and Applied Mathematics of the University of Crete, there will be a public presentation and support of the Doctoral Thesis of the PhD candidate of the Department of Materials Science and Engineering, Mr. Konstantinos Loukelis, on the subject :

«Fabrication of Electrospun and 3D Bioprinted Scaffolds for Bone Tissue Engineering Using Natural and Synthetic Biomaterials»

Abstract

Bone tissue engineering (BTE) is a broad research field that focuses on the use of biomaterial-based platforms combined with regeneration competent cell types and biochemical stimulants such as growth factors towards the fabrication of scaffolds and constructs that can restore, improve, or regenerate bone tissues. These biomaterial-based scaffolds should have a biocompatible character, controllable degradation rate, low immunogenicity, and mechanical attributes that are equivalent to those met in the native bone. State of the art biomaterials processing techniques such as electrospinning and 3D bioprinting have enabled the production of such scaffolds of varying 2D or 3D dimensionality, with topological and chemical structure that closely mimics that of bone tissue. The main objective of this thesis was the development of innovative bone regeneration promoting scaffolds and constructs based on the combination of two water soluble polymers, gellan gum (GG) and polyvinyl alcohol (PVA), via the state of the art technologies of electrospinning and 3D bioprinting. Through optimization of biomaterials composition, we produced stable GG:PVA nanofibrous scaffolds of various concentration ratios and verified that increased GG concentration and thermal treatment of scaffolds led to significantly reduced degradation rates, matching those of flat bones, while all compositions showed excellent osteogenic responses in the presence of pre-osteoblastic cells. We then biofabricated 3D bioprinted constructs, containing PVA:GG at different ratios, with and without the implementation of nano-hydroxyapatite (nHA), an osteogenic inorganic material present in human bone, and examined their biomechanical responses. It was corroborated that lower GG:PVA ratio compositions presented enhanced printability and cell viability than the stiffer counterparts, while the presence of nHA resulted in significantly enhanced printing fidelity and osteogenic capacity. Based on the optimization of the GG:PVA bioprinting conditions, we bioprinted constructs with human adipose derived stem cells (ADSCs), by incorporating zinc substituted mesoporous bioactive glasses (Zn-MBGs) in the same polymeric matrix, and observed excellent osteogenesis and chondrogenesis related cellular responses showcasing promising aspects for further use of these composite bioinks as potential personalized human osteochondral implants.

Παρουσίαση Διδακτορικής Διατριβής κ. Κωνσταντίνου Μαυράκη

07 Ιουνίου 2024

Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής του

κ. Κωνσταντίνου Μαυράκη

Επιβλέπων: Ιωάννης Ζαχαράκης

(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)

Την Τρίτη 11 Ιουνίου 2024 και ώρα 14:00

στην αίθουσα Τηλεεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Κωνσταντίνου Μαυράκη, με θέμα:

«Development of a Multiparametric Label-Free Imaging System for the Early Diagnosis of Neurodegenerative Disorders through the Ocular Cavity»

Περίληψη

“In this novel imaging system, we have combined three non-invasive and label-free imaging techniques: Optoacoustic microscopy (OAM) , non-linear microscopy (NLM) and Stimulated Raman Scattering (SRS) microscopy. OAM exhibits resolution comparable to that of optical microscopy, but can penetrate deeper into high-scattering tissue. The increased possibilities stem from the fundamental scattering difference between light and sound, which constitute the signal for optical microscopy and OAM, respectively. NLM includes two photon excitation fluorescence (TPEF) and Second Harmonic Generation (SHG). OAM, TPEF, SHG and SRS are combined complementary and thus reveal a wide range of discrete and non overlapping information. TPEF presents crisp contrast between bio-molecules that possess different excitation or emission spectra. SHG can provide information about biological structures such as lipid depositions while OAM pinpoints photon absorbing molecules with non-radiative relaxation. SRS imaging provides chemical information with high specificity allowing molecular pattern recognition inside tissues and their association with diseases and pathological conditions. Using these techniques, even sensitive and unreachable structures like the retina and the ocular cavity can be investigated with high resolution. The nerve fibers in the ocular cavity are essentially an extension of the central nervous system and since several neurodegenerative disorders present symptoms in the cavity, they could be diagnosed before the manifestation of conventional symptoms. The presence of possible bio-markers was investigated with TPEF, SHG and OAM in retina samples from mouse models of Alzheimer's disease."

Παρουσίαση Διδακτορικής Διατριβής κ. Ευάγγελου Ανδρέου

06 Ιουνίου 2024

Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής του

κ. Ευάγγελου Ανδρέου

Επιβλέπων Καθηγητής: Γεράσιμος Αρματάς

(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)

Την Πέμπτη 13 Ιουνίου 2024 και ώρα 10:00 στην αίθουσα Τηλεεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Ευάγγελου Ανδρέου, με θέμα:

«Porous Mesoscopic Assemblies of Spinel Chalcogenide and Transition Metal Phosphide Nanoparticles for Photocatalytic Energy Conversion Applications»

Περίληψη

The persistent rise in fossil fuel consumption, driven by the need to satisfy current energy demands, poses a significant environmental hazard, primarily due to the substantial emissions of hazardous gases into the atmosphere. While it is evident that renewable energy sources must replace a significant portion of fossil fuels, existing renewable energy production methods often lack efficiency and still present environmental challenges. Photocatalytic water splitting for hydrogen production stands out as a low-cost technique, offering a high solar to chemical conversion efficiency while emitting zero hazardous gases. Over the last few decades, the research community has explored various photocatalysts, including metal oxides, chalcogenides, nitrides, and more. Despite considerable progress in the development of photocatalytic materials, current synthetic methods often fail to provide precise control over electrochemical properties, morphology, and size of particles, leading to subpar photocatalytic performance.

In this dissertation, we introduce a new, cost-effective and environmentally friendly synthetic protocol for fabricating mesoporous networks of interconnected thiospinel (MIn₂S₄, M = Zn, Cd) nanocrystals, serving as versatile building blocks. This synthetic approach provides the advantage of adjusting the size of the constituent inorganic nanocrystals, offering significant benefits for photocatalytic energy conversion applications. Such a controllable synthesis enables precise engineering of the optical and electronic properties of the resulting photocatalysts. Namely, employing a straightforward polymer-templated self-assembly process, the thiospinel nanocrystals are organized into three-dimensional (3D) mesoporous networks with large internal surface area and we-defined pores. This structural arrangement leads to improved charge transfer kinetics and better intraparticle diffusion of the electrolyte. Given their advantageous characteristics, the mesoporous ensembles were investigated as potential photocatalysts for the water splitting reaction towards hydrogen evolution. Furthermore, by carefully selecting suitable co-catalysts such as Ni₂P, Co₂P, and β-Ni(OH)₂, we uncovered their significant impact on the photochemical properties of the resulting composite structures. Utilizing a combination of spectroscopic and (photo)electrochemical techniques, we identified that the formation of the thiospinel/metal phosphide/hydroxide nano-heterojunctions significantly enhances the separation and transfer ability of the photogenerated charge carriers, leading to high photocatalytic stability and activities. Notably, these improvements exceed those reported for previously studied high-performance multicomponent thiospinel-based photocatalytic systems. Overall, this research presents a novel synthetic perspective for the rational design of photocatalysts and advances our understanding of next generation photocatalysts for clean energy conversion applications. By shedding light on key aspects of inorganic synthetic chemistry, interface engineering and photochemical reactions, the findings of this work make a significant contribution to the broader research endeavor focused on the development of sustainable energy technologies.

Παρουσίαση Διδακτορικής Διατριβής κ. Μιχαήλ Μυλωνάκη

30 Μαΐου 2024

Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής του

κ. Μιχαήλ Μυλωνάκη

Επιβλέπων: Ιωάννης Ζαχαράκης

(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)

Την Πέμπτη 6 Ιουνίου 2024 και ώρα 10:00 στην αίθουσα Τηλεεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Μιχαήλ Μυλωνάκη, με θέμα:

«Wavefront Shaping for Microscopic Imaging of Biological Samples»

Περίληψη

“Imaging of biological samples is one of the driving application fields of optical microscopy. Although several other imaging techniques have been developed the simplicity, the effectiveness and the non-invasive nature of optical microscopy are the key factors of its widespread use in Biology.

An important limiting factor for optical microscopy is the scattering of light as it propagates through biological tissue. The inherent random variations of the optical properties, lead to a diffusion dominated propagation that drastically limits the effective imaging range down to 1 mm. On the other hand, recent advances in the spatial modulation of the light beam that illuminates the sample combined with analysis of the detected light distribution have opened the way to beat the diffusion limit.

Τhis PhD thesis was focused on leveraging the concept of the 'opaque lens' by utilizing engineered disorder in photonic structures. This involved developing novel scattering media and their integration with wavefront shaping into imaging modalities. Using this approach, we have reached to the development of a fully functional fluorescence microscope that, in several aspects, outperforms current instrumentation capable of performing in vivo fluorescence microscopy."

Call for Applications for Admission to the M.Sc. Program in “Biomedical Engineering”, 2024-2025

19 Μαΐου 2024

The School of Medicine, the Department of Computer Science, the Department of Materials Science and Engineering of the University of Crete (UoC), the School of Electrical and Computer Engineering of the Technical University of Crete (TUC), and the Foundation for Research and Technology - Hellas (FORTH) announce that applications for the academic year 2024-2025 for the Joint Master's Program in "Biomedical Engineering" are now open!

The objective of the joint MSc Program in Biomedical Engineering is to provide advanced education, required qualifications and skills to its graduates to meet the ever-increasing demand for high-level specialization in the field of biomedical engineering. Graduates of our joint MSc program in BME may be employed in hospitals, medical equipment / instrumentation industry, pharmaceutical industry, government agencies or follow academic careers towards pursuing a PhD degree. The official instruction language of the program is English.

The deadline for submitting the application and supporting documents is May 26, 2024.

For more information about the program and the application procedure, please visit the site.

Πρόσκληση Παρουσίασης Διδακτορικής Διατριβής του κ. Εμμανουήλ Ορφανάκη

09 Μαΐου 2024

Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής

του κ. Εμμανουήλ Ορφανάκη

Επιβλέπων: Μιχαήλ Βελεγράκης

(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)

Την Τετάρτη 15 Μαΐου 2024 και ώρα 11:00 στην αίθουσα Τηλεεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης,

θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Εμμανουήλ Ορφανάκη, με θέμα:

«Development of Photonics Based Methodologies for the Assessment of Agricultural Products and Environmental Pollutants.»

 Περίληψη

“Quality control and safety of agrofood products are of high importance due to their significant commercial and nutritional value. However, these products are prone to fraud and contamination, posing risks to consumer health. Traditional methods for detecting adulterants and contaminants are accurate but expensive and time-consuming, often requiring specialized facilities. In recent years, the application of optical spectroscopic techniques has emerged as a promising alternative for studying agrofood products. These methods offer rapid analysis, minimal sample pretreatment, and cost-effectiveness. By combining optical spectroscopy with multivariate statistical (machine learning) techniques, it becomes possible to authenticate and control the quality of agrοfood products effectively. The focus of this doctoral thesis is on the development and application of photonics methodologies in two vital agrofood products: olive oil and honey. Α comprehensive study has been conducted on a large number of honey samples using various optical spectroscopic techniques to differentiate botanical origins and predict essential physicochemical parameters. Similarly, extensive research has been undertaken on olive oil to identify varieties and predict chemical compositions accurately. Notably, a novel method, based on fluorescence spectroscopy has been developed for the rapid and cost-effective detection of contaminants such as Polycyclic Aromatic Hydrocarbons and mineral oils. This work, conducted at the Laboratory of Photonics for Agrofood and Environment (Agrophotonics) of the Institute of Electronic Structure and Laser of FORTH, aims to provide practical and affordable solutions for ensuring the origin, safety, and quality of food products.”

Προκήρυξη του βραβείου “ΑΡΙΣΤΗΣ ΔΙΔΑΚΤΟΡΙΚΗΣ ΔΙΑΤΡΙΒΗΣ” για έτος 2024

08 Μαΐου 2024

Δείτε τη σχετική προκήρυξη.

Η ηλεκτρονική διεύθυνση υποβολής προτάσεων είναι: vraveia@uoc.gr με την ένδειξη "Για το βραβείο Άριστης Διδακτορικής Διατριβής" και η καταληκτική ημερομηνία η 31η Μαΐου 2024.

Μεταπτυχιακό σε “Νανοτεχνολογία για Ενεργειακές Εφαρμογές”

22 Απριλίου 2024

Δείτε την πρόσκληση για υποβολή αιτήσεων για τον τρίτο κύκλο του Διιδρυματικού Προγράμματος Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) «Νανοτεχνολογία για Ενεργειακές Εφαρμογές – Nanotechnology for Energy Applications» (ΦΕΚ 1973/01-06-2018).

Προθεσμία υποβολής αιτήσεων είναι η 23η Σεπτεμβρίου 2024.

Ημερομηνία διεξαγωγής συνεντεύξεων υποψηφίων φοιτητών είναι η 30η Σεπτεμβρίου 2024

Postgraduate Studies on Soft Matter Science & Engineering in the Department of Materials Science and Technology of the University of Crete

04 Απριλίου 2024

Call for Applications for Postgraduate Studies on

Soft Matter Science & Engineering

in the Department of Materials Science and Technology

of the University of Crete

The aim of the Soft Matter Science & Engineering Postgraduate Program is to provide students with the needed skills to pursue successful careers or further advanced studies in the highly interdisciplinary field of soft materials. The educational and research activities of the program provide an integrated approach and in-depth training, with emphasis on conducting innovative research in a variety of soft matter fields, including (but not limited to) synthesis and characterization, polymers, colloids, composites, interfacial properties, materials for energy, biomimetic materials, responsive networks, materials for biological or biomedical applications, eco-friendly and sustainable materials, recycling, rheology and processing. 

Successful completion of the Program leads to a Postgraduate Diploma (MSc) after 4 semesters of study that include mandatory attendance of courses (2 semesters) and submission and oral defense of a Master's Thesis (2 semesters). Internships will be offered in the summer period between the first and second year. The program is in English and requires full-time participation. As part of their training, postgraduate students assist in the instruction of undergraduate courses.

The tuition fees are 3.500€ for the entire program. Scholarships may be available.

Graduates of the first cycle of studies of any Institution have the right to apply for the program. International students should have a degree equivalent.

Eligible candidates should hold a degree in Sciences or Engineering. Good knowledge of English (B2 level and above) is required. Candidates who have not graduated during the application period will be considered, but possible eventual enrollment is subject to receiving their first degree until the end of October 2024.

The academic criteria that are taken into account for the selection, as defined in the Postgraduate Studies Regulations, include the undergraduate degree, recommendation letters, grades in courses relevant to the program, the senior thesis (if applicable), as well as the applicant’s relevant research or professional activity (if applicable).

Necessary supporting documents:

• Application
• Detailed CV
• Report of interests
• Diploma supplement
• Up to three (3) letters of recommendation
• Certificate of a good knowledge of the English language (B2 level and above)
• Any other document the applicant considers to be evidence of scientific excellence and quality.

The application must include an e-mail account, from which the applicant will be informed about the progress of his/her application.

Letters of recommendation should be sent directly from the authors to the postgraduate secretariat stratigis@materials.uoc.gr.

Deadline for submission of the application and supporting documents for the Postgraduate Program is set for May 24, 2024. The candidates will be informed about possible (online) interviews by May 31, 2024.

Applications and supporting documents are submitted exclusively online to the postgraduate secretariat stratigis@materials.uoc.gr before the deadline.

For more information, please contact the Secretariat of the Department of Materials Science and Technology, Mr. Ch. Stratigis (tel. +30 2810-394272, (stratigis@materials.uoc.gr) or the Director of Postgraduate Program on Soft Matter Science & Engineering, Prof. D. Vlassopoulos (dvlasso@materials.uoc.gr ).