Filtry
wszystkich: 1489
-
Katalog
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: MICROWAVE-ASSISTED REACTIONS
-
Addressing challenges of BiVO4 light-harvesting ability through vanadium precursor engineering and sub-nanoclusters deposition for peroxymonosulfate-assisted photocatalytic pharmaceuticals removal
PublikacjaIn this study, we present a complex approach for increasing light utilisation and peroxymonosulfate (PMS) activation in BiVO4-based photocatalyst. This involves two key considerations: the design of the precursor for BiVO4 synthesis and interface engineering through CuOx sub-nanoclusters deposition. The designed precursor of ammonium methavanadate (NH4VO3, NHV) leads to reduction in particle size, better dispersion and improved light...
-
Single and Dual-GPU Generalized Sparse Eigenvalue Solvers for Finding a Few Low-Order Resonances of a Microwave Cavity Using the Finite-Element Method
PublikacjaThis paper presents two fast generalized eigenvalue solvers for sparse symmetric matrices that arise when electromagnetic cavity resonances are investigated using the higher-order finite element method (FEM). To find a few loworder resonances, the locally optimal block preconditioned conjugate gradient (LOBPCG) algorithm with null-space deflation is applied. The computations are expedited by using one or two graphical processing...
-
An experimental and theoretical study of the hetero Diels–Alder reactions between (E)-2-aryl-1-cyano-1-nitroethenes and ethyl vinyl ether: one-step or zwitterionic, two-step mechanism?
Publikacja -
Measuring moisture damage of hot-mix asphalt (HMA) by digital imaging-assisted modified boiling test (ASTM D3625): Recent advancements and further investigation
Publikacja -
DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN SOIL SAMPLES USING ULTRASONIC PROBE AND SALT-ASSISTED LIQUID-LIQUID EXTRACTION COUPLED WITH HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY
Publikacja -
Favourable outcomes in patients with early-stage non-small-cell lung cancer operated on by video-assisted thoracoscopic surgery: a propensity score-matched analysis†
Publikacja -
High-Throughput Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry as an Alternative Approach to Monitoring Drug Resistance of Hepatitis B Virus
Publikacja -
TiO2-C nanocomposite synthesized via facile surfactant-assisted method as a part of less energy-consuming LED-based photocatalytic system for environmental applications
PublikacjaA novel facile method was used to incorporate carbon into the titania structure. An alternative synthesis method of carbon-doped TiO2 has been proposed by using a widely used and cheap surfactant. During the process, cetyltrimethylammonium bromide plays a dual role, as a morphology modifier and as a carbon source. The presented approach allows obtained TiO2-C nanostructures to be anatase nanocrystals with carbon being deposited...
-
Miniaturized bandpass substrate integrated waveguide filter with frequency-dependent coupling realized using asymmetric GCPW discontinuity
PublikacjaAn asymmetric GCPW discontinuity is proposed to provide frequency-dependent coupling in microwave bandpass filters. Wider and narrow sections introduce, respectively, the capacitive and inductive component to the equivalent circuit representing coupling. By selecting the dimensions of the discontinuity and width of the inductive window in substrate integrated waveguide, an additional transmission zero can be introduced at prescribed...
-
Reactions of Lithium Salts of Triphosphanes tBu2P-PLi-PtBu2 and tBu2P-PLi-P(NEt2)2 with Metal Complexes [(R3P)2MCl2] (M = Ni, Pd, Pt, R3P = Et3P, pTol3P, Ph2EtP, iPr3P)
PublikacjatBu2P-PLi-PtBu2·2THF reacts with [(R3P)2MCl2] (M = Pt, Pd, Ni; R3P = Et3P, pTol3P, Ph2EtP, iPr3P) to yield isomers of [(1,2-η-tBu2P=P-PtBu2)M(PR3)Cl], in which the tBu2P-P-PtBu2 ligand adopts the arrangement of a side-on bonded 1,1-di-tert-butyl-2-(di-tert-butylphosphanyl)diphosphenium cation. tBu2P-PLi-P(NEt2)2·2THF reacts with [(R3P)2MCl2] but does not form complexes with a tBu2P-P-P(NEt2)2 moiety, however, splitting...
-
Dimethylimidazole and dicyandiamide assisted synthesized rich-defect and highly dispersed CuCo-Nx anchored hollow graphite carbon nanocages as efficient trifunctional electrocatalyst in the same electrolyte
Publikacja -
Ultrasound assisted solvent extraction of porous membrane-packed samples followed by liquid chromatography-tandem mass spectrometry for determination of BADGE, BFDGE and their derivatives in packed vegetables
PublikacjaThe problem of the presence of trace organic pollutants in food is of growing importance due to increasing awareness about their impact on newborns, infants and adults of reproductive age. Despite the fact that packaged food products offer many advantages, packaging can be a source of contamination for stored food. Thus, monitoring such pollution in food is of high importance. In this work, a novel methodology based on the solvent...
-
Mechanistic insights into the reactive radicals-assisted degradation of sulfamethoxazole via calcium peroxide activation by manganese-incorporated iron oxide–graphene nanocomposite: Formation of radicals and degradation pathway
Publikacja -
Ionic liquid-assisted sol-gel synthesis of Fe2O3-TiO2 for enhanced photocatalytic degradation of bisphenol a under UV illumination: Modeling and optimization using response surface methodology
Publikacja -
Reactions of tBu2P-PLi-P(tBu)2 with [(Et3P)2MCl2] (M = Ni, Pd, Pt). Synthesis and properties of [(1,2-h-tBu2P=P-P(tBu)2)M(PEt3)Cl] (M=Ni, Pd)
PublikacjatBu2P-PLi-P(tBu)2*2THF reaguje z [(Et3P)2MCl2] (M = Ni, Pd) dając odpowiednio [(1,2-h-tBu2P=P-P(tBu)2)Ni(PEt3)Cl] i [(1,2-h-tBu2P=P-P(tBu)2)Pd(PEt3)Cl]. Związek tBu2P-PLi-P(tBu)2 utlenia się i ligand tBu2P-P-P(tBu)2 przyjmuje w produktach strukturę bocznie związanego kationu z krótkim wiązaniem P-P. Reakcja ze związkami platyny nie dała oczekiwanych produktów.
-
Modeling and optimizing the removal of cadmium by Sinapis alba L. from contaminated soil via Response Surface Methodology and Artificial Neural Networks during assisted phytoremediation with sewage sludge
Publikacja -
The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublikacjaIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
-
Miniaturized dual‐band branch‐line coupler with enhanced bandwidth
PublikacjaIn this letter, a miniaturized hybrid dual-band branch-line coupler (BLC) with enhanced fractional bandwidths is proposed. Compact size and bandwidth enhancement are obtained using meandered transmission line sections with broken symmetry between cross-coupling branches. The circuit is designed at a low numerical cost using surrogate-assisted techniques. The optimized design features small size of only 0.25λg×0.19λg(28% miniaturization...
-
Spectroscopic evaluation of a low power atmospheric pressure mixed argon–helium microwave induced plasma combined with the chemical generation of volatile species for the optical emission spectrometric determination of arsenic, antimony and mercury
Publikacja -
Zero-Pole Electromagnetic Optimization
PublikacjaA fast technique for the full-wave optimization of transmission or reflection properties of general linear timeinvariant high-frequency components is proposed. The method is based on the zeros and poles of the rational function representing the scattering parameters of the device being designed and it is the generalization of the technique developed for the design by optimization of microwave filters. The performance of the proposed...
-
Zero-Pole Space Mapping for CAD of Filters
PublikacjaIn this paper, we propose a new space-mapping technique tailored to the CAD of microwave filters. The goal of space mapping is to achieve a satisfactory design with the minimal number of fine model evaluations. In our approach, the filter is represented by a rational function. To quickly align the coarse and fine models, and to speed up the direct optimization of the coarse model, we propose matching the zeros and poles of a rational...
-
Fast EM-driven optimization using variable-fidelity EM models and adjoint sensitivities
PublikacjaA robust and computationally efficient technique for microwave design optimization is presented. Our approach exploits variable-fidelity electromagnetic (EM) simulation models and adjoint sensitivities. The low-fidelity EM model correction is realized by means of space mapping (SM). In the optimization process, the SM parameters are optimized together with the design itself, which allows us to keep the number...
-
On the low-cost design of abbreviated multisection planar matching transformer
PublikacjaA numerically demanding wideband matching transformer composed of three nonuniform transmission lines (NUTLs) has been designed and optimized at a low computational cost. The computational feasibility of the design has been acquired through the exploitation of low-fidelity NUTL models in most steps of the design procedure and an implicit space mapping optimization engine, providing high accuracy results with only a handful of EM...
-
Adam Lamęcki dr hab. inż.
Osoby -
Chemistry and Nanochemistry 2023
Kursy OnlineWe start from General Chemistry, including: calculus in chemistry, bonds, balancing the chemical reactions, redox reactions, electrochemistry, pH, acids, bases, salts, oxides, organic molecules, and many informations about synthesis, analysis and applications in nanochemistry.
-
A robust design of a numerically demanding compact rat-race coupler
PublikacjaA fast and accurate design procedure of a computationally expensive microwave circuit has been presented step-by-step and experimentally validated on the basis of a compact rat-race coupler (RRC) comprising slow-wave resonant structures (SWRSs). The final compact RRC solution has been obtained by means of a sequential optimization scheme exploiting the implicit space mapping (ISM) algorithm. A well-suited surrogate optimization...
-
Materials science. Quantum particle approach. 2023.
Kursy OnlineQuantum ideas applied for particle systems and for chemical reactions.
-
A Trisection Filter Design With Negative Slope of Frequency-Dependent Crosscoupling Implemented in Substrate Integrated Waveguide (SIW)
PublikacjaThis letter reports on a novel realization of a microwave bandpass filter in a triplet configuration with a frequency-dependent crosscoupling implemented in substrate integrated waveguide (SIW). The design involves implementing dispersive coupling with a negative slope, a feature that allows the capabilities of the classic triplet topology to be extended. In this particular case, the implementation of two transmission zeros on...
-
Results and models for Novel high frequency components with non-conventional shape employing smooth geometry deformation of 3D solid with FFD
Dane BadawczeThe project aims to investigate the possibility of developing and manufacturing novel high frequency devices having non-standard geometries, allowing for improved electromagnetic performance over what is achievable with currently available design tools. The non-conventional geometry will be obtained by employing the free-form shape deformation technique...
-
Dariusz Witt prof. dr hab. inż.
Osoby -
A Compact Basis for Reliable Fast Frequency Sweep via the Reduced-Basis Method
PublikacjaA reliable reduced-order model (ROM) for fast frequency sweep in time-harmonic Maxwell’s equations by means of the reduced-basis method is detailed. Taking frequency as a parameter, the electromagnetic field in microwave circuits does not arbitrarily vary as frequency changes, but evolves on a very low-dimensional manifold. Approximating this low-dimensional manifold by a low dimension subspace, namely, reduced-basis space, gives...
-
Artificial intelligence for software development — the present and the challenges for the future
PublikacjaSince the time when first CASE (Computer-Aided Software Engineering) methods and tools were developed, little has been done in the area of automated creation of code. CASE tools support a software engineer in creation the system structure, in defining interfaces and relationships between software modules and, after the code has been written, in performing testing tasks on different levels of detail. Writing code is still the task...
-
Near-Field Wireless Sensing of Plastics and Papers Using Frugal Peel-Off Passive Tag
PublikacjaThis article presents a novel frugal approach of testing plastics and papers using a near-field microwave sensing technique with a peel-off tag. The proposed sensing technique involves two electrical entities: the sensor, which may be regarded as a reader, and a disposable tag. The reader is a modified design of a gap-coupled microstrip line (GCML) sensor, while the passive tag is a standard double-ring complementary split-ring...
-
A Substrate Integrated Waveguide (SIW) Bandpass Filter in A Box Configuration With Frequency-Dependent Coupling
PublikacjaThis letter presents the design of a microwave bandpass filter with frequency-dependent coupling implemented in substrate integrated waveguide (SIW) technology. The proposed filter implements a four-pole generalized Chebyshev filtering function with two transmission zeros. Resonators are arranged in an extended box configuration with dispersive coupling on a main signal path, which produces an extra zero in comparison to classical...
-
A Linear Phase Filter in Quadruplet Topology With Frequency-Dependent Couplings
PublikacjaThis letter presents a design of a linear phase microwave bandpass filter. The filter is composed of four resonators arranged in the quadruplet topology. Making the cross and one direct coupling dispersive gives additional design flexibility. The first advantage of using frequency-dependent couplings is the possibility to chose an arbitrary location of a pair of complex transmission zeros (TZs) in the s-domain. The second one is...
-
Piotr Kowalczyk dr hab. inż.
Osoby -
Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublikacjaAccurate performance evaluation of microwave components can be carried out using full‐wave electromagnetic (EM) simulation tools, routinely employed for circuit verification but also in the design process itself. Unfortunately, the computational cost of EM‐driven design may be high. This is especially pertinent to tasks entailing considerable number of simulations (eg, parametric optimization, statistical analysis). A possible...
-
Dispersive Delay Structures With Asymmetric Arbitrary Group-Delay Response Using Coupled-Resonator Networks With Frequency-Variant Couplings
PublikacjaThis article reports the design of coupled-resonatorbased microwave dispersive delay structures (DDSs) with arbitrary asymmetric-type group delay response. The design process exploits a coupling matrix representation of the DDS circuit as a network of resonators with frequency-variant couplings (FVCs). The group delay response is shaped using complex transmission zeros (TZs) created by dispersive cross-couplings. We also present an...
-
Wykorzystanie metody Neldera-Meada do identyfikacji wartości parametrów niequasi-statycznego modelu małosygnałowego tranzystora MOS
PublikacjaW artykule zaprezentowano wyniki zastosowania metody sympleksu Neldera-Meada do ekstrakcji wartości parametrów niequasi-stycznego modelu małosygnałowego tranzystora MOS. Przedstawiono równoważny elektryczny schemat zastępczy i model matematyczny nowego modelu małosygnałowego MOSFETa dla częstotliwości mikrofalowych. Opisano zaimplementowany algorytm i otrzymane rezultaty badań.
-
A closer look at how the dispersive liquid–liquid microextraction method works. Investigation of the effect of solvent mixture composition on the quality and stability of the cloudy state
PublikacjaThe dispersive liquid–liquid microextraction (DLLME) is one of the most popular miniaturized extraction procedures. In this paper, the degree of dispersion and dispersion stability were studied with the aim to assess the correlations of these parameters with efficiency for the selected analytical application. The dependence between the degree of dispersion (cloudy state quality) and its stability obtained by various emulsification...
-
Parametrized Local Reduced-Order Models With Compressed Projection Basis for Fast Parameter-Dependent Finite-Element Analysis
PublikacjaThis paper proposes an automated parametric local model-order reduction scheme for the expedited design of microwave devices using the full-wave finite-element method (FEM). The approach proposed here results in parameterized reduced-order models (ROMs) that account for the geometry and material variation in the selected subregion of the structure. In each subregion, a parameter-dependent projection basis is generated by concatenating...
-
Reactions of R2P-P(SiMe3)2 with [(R'3P)2PtCl2]. Syntheses and Structures of [μ2-(1,2:2-η-P2){Pt(PEt3)2}2{Pt(PEt3)2Cl}]+Cl-, [{(Et2PhP)2Pt}2P2], [{(p-Tol3P)2Pt}2P2] and [(p-Tol3P)ClPt(μ-PPh2)2Pt(p-Tol3P)Cl]
PublikacjaReakcje difosfanów R2P-P(SiMe3)2 z [(R'3P)2PtCl2] są bardzo złożone. Główną ścieżką reakcji jest rozszczepienie wiązania P-P w startowym R2P-P(SiMe3)2, po czym następuje utworzenie kompleksu zawierającego P2: [{(R'3P)2Pt}2P2] oraz difosfanu R2P-PR2. Produkty reakcji (zarówno główne jak i uboczne), zostały scharakteryzowane na podstawie spektroskopii 31P NMR. Dla czterech tytułowych związków wykonano rentgenowską analizę strukturalną...
-
Theoretical study of the energetics of the reactions of triplet dioxygen with hydroquinone, semiquinone, and their protonated forms: relation to the mechanism of superoxide generation in the respiratory chain = Badanie teoretyczne energii z energii reakcji dioksygenu potrójnego z wodorem, półkiną i ich formami protony: relacja z mechanizmem wytwarzania supertlenku w łańcuchu oddechowym
PublikacjaW pracy prezentujemy wyniki obliczeń kwantowych ab initio i półempirycznych energetyki reakcji redukcji jednoelektronowej tlenu trypletowego. Zaproponowaliśmy cztery możliwe mechanizmy redukcji i przeprowadziliśmy obliczenia kwantowe. Z obliczeń wynika, że najprawdopodobniejszy mechanizm reakcji wiedzie poprzez przeniesienie elektronu z anionu hydrochinonu po deprotonacji lub też z rodnika semichinonowego na tlen cząsteczkowy,...
-
A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
PublikacjaThis paper reports a novel synthesis method for microwave bandpass filters with resonant source–load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal coupling matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement...
-
Mateusz Rzymowski mgr inż.
Osoby -
Grzegorz Fotyga dr hab. inż.
Osoby -
Agnieszka Landowska dr hab. inż.
OsobyUkończyła studia na dwóch kierunkach: Finanse i bankowość na Uniwersytecie Gdańskim oraz Informatyka na WETI Politechniki Gdańskiej. Od 2000 roku jest związana z Politechniką Gdańską. W 2006 roku uzyskała stopień doktora w dziedzinie nauk technicznych, a w roku 2019 stopień doktora habilitowanego. Aktualnie jej praca naukowa dotyczy zagadnień interakcji człowiek-komputer oraz informatyki afektywnej (ang. affective computing), która...
-
Chemistry and Nanochemistry 2022.
Kursy OnlineThe course consists of lectures (15 x 2 hours) and laboratories (5 x 3 hours).The goal of this course is to teach general chemistry and adequately apply it to nano-size systems, their synthesis and analysis. An emphasis is laid on an analysis of electronic structure of molecules and prediction of resulting properties and reasons of consequent behaviour in chemical reactions. The course also encloses laboratory classes, where the...
-
Activation of the C=P bond in phosphanylphosphaalkenes C=P–P bond system) in the reaction with nucleophilic reagents: MeLi, nBuLi and tBuLi
PublikacjaThree reactions of phosphanylphosphaalkene (1) with nucleophiles were performed to activate the diphosphorus monomer. We observed similar results in the reactions with MeLi and nBuLi, in which the P–P bond is cleavaged and triphosphorus systems [P(Me)2–CH(biph)–CH(biph)–P–(PtBu 2)]- (1a'') and [P(nBu)2–CH(biph)–CH(biph)–P–(PtBu 2)]- (1b''), respectively, are formed depending on the nucleophilic reagent (biph ¼ biphenyl). In the...
-
Application of computer assisted modified coupled mode method for the design of polarimetric sensors. Optical Fibres and Their Applications VIII. Białowieża 23-26 stycznia 2002. Ed. J. Dorosz, R.S. Romaniuk. Wykorzystanie zmodyfikowanej metody modów sprzężonych wspomaganej komputerem do projektowania sensorów polarymetrycznych.
PublikacjaW pracy przedstawiono rozszerzenie zmodyfikowanej metody modów sprzężonych,dzięki, któremu możliwe jest modelowanie szerokiej klasy światłowodów poddanych jednoczesnemu działaniu wielu zaburzeń. W metodzie tej dokonuje się numerycznego rozwiązania równania modów sprzężonych, w wyniku czego możliwa jest analiza przypadków, w których współczynniki sprzężenia modów nie są stałe wzdłuż światłowodu. W wyniku umiejętnej modyfikacji...