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Two novel compact magic-T configurations designed as a two layer structure are proposed in this paper. They consist of a microstrip tee-junction and resonance circuit composed of a microstrip line combined with rectangular or radial stubs. These microstrip circuits are respectively printed at the top and bottom layers of the structure, and coupled via a slot located in the common ground plane. The microstrip patch and slot are placed parallel to each other forming novel microstrip-slotline transitions, which provide broadband operation of the magic-Ts. Transmission line equivalent circuits are used to explain the performance of the proposed hybrids. It is shown that magic-T with a radial stub demonstrates wider operation bandwidth and better performance than the structure with a rectangular stub. In order to validate their performance, the prototypes of both configurations were manufactured and measured. Experimental and simulation results show that the resulting magic- T using a radial resonator has a fractional bandwidth of over 40% for 0.2 dB amplitude and 0:5° phase imbalance. The experimental results are in good agreement well with equivalent circuit and full-wave simulations. [ABSTRACT FROM AUTHOR]

In this paper, a novel longitudinally magnetized cylindrical ferrite coupled line (CFCL) junction is proposed. In comparison to planar ferrite coupled line (FCL) configurations, which are well known in literature, in such structure the higher gyromagnetic coupling occurs. This allows to obtain the required in FCL devices Faraday rotation angle π/4 for the ferrite with shorter length and lower value of magnetization. As a result the total insertion losses in the ferrite section can be reduced using the proposed topology. In the analysis of the proposed CFCL junction a hybrid technique combining method of moments and coupled mode method (MoM/CMM) is applied. The results are compared with the ones obtained from commercial software HFSS and a good agreement is obtained. [ABSTRACT FROM AUTHOR]

This paper presents the investigations of nonreciprocal devices employing a novel ferrite coupled line junction. The structure is designed using coplanar line technology with the ground half-planes reduced to the strips. The investigated junction is composed of one ferrite section placed in between of two dielectric sections. In the ferrite section the longitudinally magnetized ferrite slab is located at the top or the bottom of the strips and is covered with the dielectric layers. In the dielectric sections the ports of the junctions are located. The wave parameters and field distributions of the modes propagated in the dielectric and ferrite sections are obtained from spectral domain approach. In order to determine the scattering matrix of the junction the mode matching method is utilized. The investigation of the circulator and isolator designed based on the S-matrix of the junction are presented. The obtained results are verified by comparing them with HFSS simulations and own measurements of the fabricated devices. In both cases a very good agreement is observed. [ABSTRACT FROM AUTHOR]

Inherent features of metal halide perovskites are their softness, complex lattice dynamics, and phase transitions spectacularly tuning their structures and properties. While the structural transformations are well described and classified in 3D perovskites, their 1D analogs are much less understood. Herein, both temperature- and pressure-dependent structural evolutions of a 1D AcaPbI 3 perovskitoid incorporating acetamidinium (Aca) cation are examined. The study reveals the existence of nine phases of δ-AcaPbI 3 , which present the most diverse polymorphic collection among known perovskite materials. Interestingly, temperature- and pressure-triggered phase transitions in the 1D perovskotoid exhibit fundamentally different natures: the thermal transformations are mainly associated with the collective translations of rigid polyanionic units and ordering/disordering dynamics of Aca cations, while the compression primarily affects inorganic polymer chains. Moreover, in the 1-D chains featuring the face-sharing connection mode of the PbI 6 octahedra the Pb···Pb distances are significantly shortened compared to the corner-sharing 3D perovskite frameworks, hence operating in the van der Waals territory. Strikingly, a good correlation is found between the Pb···Pb distances and the pressure evolution of the bandgap values in the δ-AcaPbI 3 , indicating that in 1D perovskitoid structures, the contacts between Pb 2+ ions are one of the critical parameters determining their properties., (© 2024 Wiley‐VCH GmbH.)

Mechanochemical methods have been successful in providing rapid access to a number of inorganic-organic functional materials under mild conditions. Recently, we demonstrated a novel mechanochemical strategy for metal-organic framework (MOF) preparation based on predesigned oxo-centered secondary building units. Herein, we develop this method for the facile preparation of the isoreticular MOF (IRMOF) family members based on a combination of an oxozinc amidate cluster, [Zn 4 (μ 4 -O)(NHOCPh) 6 ], and selected ditopic aminoterephthalate and 4,4'-biphenyldicarboxylate as well as tritopic 1,3,5-benzenetribenzoate ligands. The resulting IRMOF-3, IRMOF-10, and MOF-177 crystalline materials were characterized using powder X-ray diffraction, IR spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis. We found that the character of the organic linker strongly affects the nature of the resulting MOF crystallites after activation processes. The SEM images demonstrate that IRMOF-3 formed microcrystallites in the range of 400-500 nm, while the two other materials exhibited microstructures of amorphous phases. The porosity of each sample was estimated by N 2 sorption measurements at 77 K. These results provide an efficient and general method for the mechanosynthesis of Zn-based MOF materials using a predesigned oxozinc cluster.

Hydrolytically stable silanethiol tris(2,6-diisopropylphenoxy)silanethiol (TDST) has been synthesized and reacted with sodium metal. In solid state TDST exhibits π-interactions between the S-H unit and the π-system of the arene, replaced by cation-π interactions in its sodium salts. The interactions are documented by crystal structures and FT-IR spectroscopy.