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From soft matter dynamics to global population evolution

Monday, 06 May 2024 13:39 |

In the globalized world of the 21st century, a reliable description of the evolution of the world's population is becoming increasingly important. A critical analysis of the literature on the subject shows that the problem of the world population continues to become one of the most important cognitive challenges.

A recent publication by A. A. Sojecka and A. Drozd-Rzoska “Global Population: From Super-Malthus Behavior to Judgment Day Criticality” [Scientific Reports 14 (2024) 9853] https://doi.org/10.1038/s41598-024-60589-3, presents a novel model analysis of the evolution of the global population using a methodology originally developed by Aleksandra Drozd-Rzoska for the dynamics of complex soft matter systems, in particular for subcooled liquids, glasses, and supercritical fluids.

Pożegnanie Profesora Adama Witka

Friday, 19 April 2024 11:27 |

Z przykrością zawiadamiamy o śmierci prof. Adama Witka, który pracował w IWC PAN w latach 90–tych, początkowo przy ulicy Sokołowskiej, a następnie w świeżo powstałym laboratorium w Al. Prymasa Tysiąclecia.

Msza św. Pogrzebowa odbędzie się 23 kwietnia – we wtorek o godz. 10:00, w kościele pod wezwaniem św. Jana Apostoła i Ewangelisty, przy ulicy Bolesława Śmiałego 13 w Warszawie-Gołąbkach.

Jest także możliwość przybycia wcześniej do sali pożegnań mieszczącej się przy ul. Sosnkowskiego 36, w domu pogrzebowym Warszawa-Ursus, gdzie trumna z ciałem zostanie wystawiona od godz. 8:30 do 9:15.

Po Mszy pogrzeb odbędzie się na cmentarzu parafialnym przy ul. Wspólna Droga 25, w Jawczycach, niedaleko stacji PKP Warszawa Gołąbki.

Impact of impurity phase and high pressure growth on a stoichiometric iron-based superconductor

Thursday, 04 April 2024 14:21 |

Generally, the presence of impurity phases in a superconductor reduces its properties. Dr. Singh's research group (NL-6) has just published a new study in the Journal of Physics and Chemistry of Solids (Impact factor: 4.0) that shows the impact of impurities on high-T_c iron-based superconductors grown under ambient and applied pressure conditions.

The conclusion of this research is that the high-pressure synthesis of the stoichiometric CaKFe₄As₄ (1144) superconductor increases the transition temperature (T_c) by 2K and the critical current density (J_c) by one order of magnitude in the whole magnetic field range of 9 T as compared to that of the 1144 bulks prepared by conventional synthesis method at ambient pressure (CSP). Moreover, the superconducting onset transition temperature of this stoichiometric CaKFe₄As₄ (1144) family is robust with the presence of the common 122 (CaFe₂As₂ or KFe₂As₂) impurity phases. This study is published by “Manasa Manasa, Mohammad Azam, Tatiana Zajarniuk, Ryszard Diduszko, Tomasz Cetner, Andrzej Morawski, Andrzej Wiśniewski, Shiv J. Singh” entitled “Effect of impurity phase and high-pressure synthesis on the superconducting properties of CaKFe₄As₄” DOI: https://doi.org/10.1016/j.jpcs.2024.111996

Figure: The variation of (a) an amount of the impurity CaFe₂As₂ phase, (b) the onset transition temperature T_c^onset, (c) the room temperature resistivity (ρ_300K), (d) Residual resistivity ratio (RRR = ρ_{300 K}/ρ_{40 K}), (e) transition width (ΔT) and (f) the critical current density (J_c) at 5 K and self-field with respect to CaKFe₄As₄ bulks prepared by high pressure and high temperature synthesis (HP-HTS) method with 1144 sample prepared by CSP method.

Wielkanoc 2024

Tuesday, 26 March 2024 18:45 |

Symposium I at E-MRS Fall Meeting

Friday, 26 April 2024 11:04 |

This year Anna KAFAR from our Instutute together with Takuya MAEDA, Matteo MENEGHINI, and Eva MONROY organize Symposium I “III-nitrides and their use in electronics and optoelectronics” within the E-MRS 2024 Fall Meeting & Exhibit. Conference is organized at the University of Technology in Warsaw, Poland from 16^th to 19^th September 2024.

The symposium is a platform for exchanging research results and discussions related to III-nitride semiconductor growth, characterization and device fabrication. This includes traditional materials: GaN, InGaN, AlGaN, as well as so-called new nitrides: NbN, ScAlN. All the information is here.

Submission Deadline: June 6 (Thursday), 2024

Notification about decision: July 15 (Thursday), 2024

More info and submission: https://www.european-mrs.com/iii-nitrides-and-their-use-electronics-and-optoelectronics-emrs

Study of liquid crystals with nanoparticles

Thursday, 11 April 2024 09:32 |

Research carried out at our Institute in the NL10 laboratory has shown interesting properties of nanocollides based on a liquid crystal (MBBA) with the addition of BaTiO₃ nanoparticles. Previous work by this group has already shown that adding a minimal amount of nanoparticles fundamentally changes the properties of the system. This time, the properties were examined in the direction perpendicular to the long axis of the molecules.

The studied nanocolloids showed that in the isotropic phase a pre-transition effect of the dielectric constant is observed, which can be related to the so-called negative specific heat. In the nematic phase, which undergoes supercooling, a very strong signature of passing the melting point appears despite the lack of crystallization. The very strong pre-melting effect in the solid phase is explained on the basis of a concept combining the Lipovsky model for nanolayers of liquids between two surfaces, and the hypothesis of the appearance of negative pressures in these layers - leading to the Mossotti Catastrophe behavior. This work also shows for the first time a simple parameterization of changes in electrical permittivity in the low-frequency region (which was a previously unsolved problem) and a previously unknown critical anomaly of the dissipation coefficient, i.e. D = tgδ related to energy dissipation.

Th work is published in Open Access paper: A. Drozd-Rzoska, J. Łoś, S.J. Rzoska, The dominance of pretransitional effects in the liquid crystal based nanocolloids: nematogenic MBBA with the transverse permanent dipole moment and BaTiO₃ nanoparticles, Nanomaterials 2024, 14, 655 (Impact Factor: 5.3).

Fig. Temperature evolutions for tgδ loss (energy dissipation) factor for frequency f=12Hz in MBBA and related nanocolloids with BaTiO₃ nanoparticles. The solid green and blue curves are for the critical-like empirical parametrization D(T)=tgδ=δ^*+d(T-T_{_δ})+D(T-T_δ)^{^Ѱ} with exponent Ѱ≈4. Note the link of this magnitude to the power loss: P=ωCV^²tgδ.

Publiczna obrona rozprawy doktorskiej mgr inż. Natalii Fiuczek

Wednesday, 03 April 2024 14:28 |

Dnia 15 kwietnia 2024 r. (poniedziałek) o godz. 12:00 w sali seminaryjnej Instytutu Wysokich Ciśnień Polskiej Akademii Nauk w Warszawie, ul. Sokołowska 29/37, odbędzie się publiczna obrona rozprawy doktorskiej mgr inż. Natalii Fiuczek.

Temat rozprawy: „Mechanizm trawienia elektrochemicznego GaN oraz jego zastosowanie w inżynierii urządzeń optoelektronicznych”

Pełna treść zawiadomienia

Rozprawa doktorska oraz jej recenzje dostępne są na stronie BIP IWC PAN

Gala XIV edycji programu LIDER

Friday, 22 March 2024 13:33 |

Wczoraj, 21 marca 2024, odbyła się uroczysta gala XIV edycji programu LIDER, realizowanego przez Narodowe Centrum Badań i Rozwoju ze środków Ministerstwa Nauki i Szkolnictwa Wyższego.

Pamiątkowe dyplomy i symboliczne czeki wręczali laureatom wicepremier, minister cyfryzacji dr Krzysztof Gawkowski, wiceminister nauki i szkolnictwa wyższego prof. dr hab. inż. Marek Gzik oraz p.o. dyrektor NCBR, prof. dr hab. inż. Jerzy Małachowski.

Aż dwoje z 41 laureatów programu LIDER pracuje w naszym Instytucie. Są to dr inż. Tomasz Sochacki z Laboratorium Krystalizacji i dr inż. Marta Sawicka z Laboratorium Epitaksji MBE. Jesteśmy dumni, że ci młodzi naukowcy będą realizować tu swoje badania. Zachęcamy do zapoznania się z ich projektami opisanymi w publikacji „XIV edycja Programu LIDER”.

Więcej informacji na stronie www. Nabór do XV edycji jest już otwarty i potrwa do 28 kwietnia 2024.

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