Filtry
wszystkich: 863
wybranych: 595
Wyniki wyszukiwania dla: underwater%20communications
-
Context dependent effects of ascorbic acid treatment in TET2 mutant myeloid neoplasia
Publikacja -
Pd-catalysed general access to 7-membered N/O-heterocyclic compounds as potential agents against inflammation
Publikacja -
Phosphinoborinium cation: a synthon for cationic B-P bond systems
PublikacjaHerein, we report access to phosphinoborinium cations via heterolytic cleavage of the boron-bromide bond in bromophosphinoborane. The product of the reaction was isolated as a dimeric dication possessing a planar P2B2 core. Activation of C-H and C-P bonds in the dication led to formation of the borinium-phosphaborene adduct. Reactivity studies revealed that title cation exhibits ambiphilic properties and intramolecular frustrated...
-
The comparative study of different methods of spectral analysis of electrochemical oscillations
PublikacjaOscylacje elektrochemiczne często połączone są z roztwarzaniem metali. One często wykazują niestacjonarny charakter. W związku z czym wydaje się konieczne wykonanie analizy w równoczesnej dziedzinie czasu i częstotliwości. Zaprezentowano porównanie trzech nowych metod: STFT, transformacji falkowej i rozkładu Wigner-Ville´a. Zalety tych metod zostały wypunktowane oraz wykazane zostały różnice pomiędzy analizą Fourierowską i technikami...
-
New thiourea organocatalysts and their application for the synthesis of 5-(1H-indol-3-yl)methyl-2,2-dimethyl-1,3-dioxane-4,6-diones a source of chiral 3-indoylmethyl ketenes
PublikacjaThe stereoselective properties of modified thiourea organocatalysts were tested in the Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones, which produces chiral 5-((1H-indol-3-yl)(aryl)methyl)-2,2-dimethyl-1,3-dioxane-4,6-diones. Based on a tentative reaction mechanism for ((S)-N-benzyl-2-(3-(3,5-bis (trifluoromethyl)phenyl)thioureido)-N,3,3-trimethylbutanamide organocatalysts, modifications...
-
Preparation of bicyclic β-lactam and bicyclic 1,3- oxazinone scaffolds using combined cycloaddition and metathesis processes
PublikacjaA simple, efficient two-step method for the preparation of heterobicyclic compounds was developed. Starting from 5-acyl or 5-carbamoyl-2,2- dimethyl-1,3-dioxa-4,5-dione bicyclic scaffolds of 1-azabicyclo[5.2.0]non- 3-en-9-one, 6,9,10,10a-tetrahydro-4H-[1,3]oxazino[3,2-a]azepin-4-one, and 6,9,10,10a-tetrahydro-2H-[1,3]oxazino[3,2-a]azepine-2,4(3H)-dione were prepared using cycloaddition of thermally generated ketenes to aldimines...
-
Visible light-induced photocatalytic reaction of gold-modified titanium(IV) oxide particles: action spectrum analysis
PublikacjaAnalizy spektrum działania wykazały, ze wzbudzenie powierzchniowego plazmonu złota inicjuje utlenianie 2-propanolu w świetle widzialnym w napowietrzonej zawiesinie tlenku(IV) tytanu zmodyfikowanego zlotem. Badania przeprowadzone z użyciem światła polichromatycznego wykazały, ze szybkość reakcji foto-utleniania zależy od właściwości tlenku(IV) tytanu, takich jak rozmiar ziaren, pola powierzchni właściwej, formy krystalicznej (anataz...
-
TMSCL as a rate accelerating additive in acylations of amines with 5-(α- amino-α'-hydroxy)methylene meldrum's acids
PublikacjaAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
-
One-step formation of n-alkenyl-malonamides and n-alkenyl-thiomalonamides from carbamoyl meldrum's acids.
PublikacjaA one-pot synthesis for the preparation of N-alkenyl-malonamides and N-alkenyl-thiomalonamides was developed. 5-[Hydroxy/mercapto(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione act as a source of ketenes that react with the tautomeric form of alkyl-(2-phenyl-propylidene)-amines. A possible [2+2] or [4+2] cycloaddition product of ketene to imines was not observed.
-
Fully enzymatic mediatorless fuel cell with efficient naphthylated carbon nanotube-laccase composite cathodes
PublikacjaAn efficient, mediator-free enzymatic glucose/O2 biofuel cell with an oxygen intensive anode based on glucose dehydrogenase is presented. In the device,the power of the biofuel cell and electrode potentials of each of the enzymatic electrodes were monitored in parallel under the biofuel cell working conditions. The carbon nanotube composite biocathode demonstrates an almost constant electrode potential vs. saturated calomel electrode...
-
Tmscl as a rate accelerating additive in acylations of amines with 5-(α-amino- α'-hydroxy)methylene meldrum's acids
PublikacjaAspects are presented of the acylation of amines, alcohols and thiols with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's acids, which, due to their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and with a...
-
Resonance-Raman spectro-electrochemistry of intermediates in molecular artificial photosynthesis of bimetallic complexes
PublikacjaThe sequential order of photoinduced charge transfer processes and accompanying structure changes were analyzed by UV-vis and resonance-Raman spectroscopy of intermediates of a Ru(II) based photocatalytic hydrogen evolving system obtained by electrochemical reduction.
-
Synthesis and reactivity of O-acyl selenophosphates
PublikacjaThe synthesis of several new O-acyl selenophosphates were investigated. The stability and reactivity of the products were studied and related to their structure.
-
Facile preparation of extremely photoactive boron-doped TiO2 nanotubes arrays
PublikacjaDoping of TiO2 nanotube arrays with boron was realized via electrochemical treatment of as-anodized titania immersed in electrolyte containing boric acid. The photoactivity of doped and pure titania was examined by means of photoelectrochemical and photocatalytic response under UV-vis irradiation. The results showed that photocurrent density of B-TNTs is remarkably higher (7.5 times) than density of pure TiO2 nanotube arrays. Furthermore,...
-
Quantum mechanical which-way experiment with an internal degree of freedom
PublikacjaFor a particle travelling through an interferometer, the trade-off between the available which-way information and the interference visibility provides a lucid manifestation of the quantum mechanical wave-particle duality. Here we analyse this relation for a particle possessing an internal degree of freedom such as spin. We quantify the trade-off with a general inequality that paints an unexpectedly intricate picture of wave-particle...
-
Powerful connection of laccase and carbon nanotubes: Material for mediator-free electron transport on the enzymatic cathode of the biobattery
PublikacjaOpisany został sposób wytwarzania koniugatów lakaza - jednościenne nanorurki węglowe i ich zastosowanie jako materiałów modyfikujacych katodę w hybrydowym bioogniwie paliwowym z cynkową anodą. Nanorurki węglowe z przyłączonymi grupami aminoetylowymi stanowiły materiał wyjściowy do chemicznego związania lakazy na ich powierzchni. Otrzymany materiał wykazywał wysoką aktywność bioelektrokatalityczną i jest obiecujacym materiałem do...
-
Generic emergence of classical features in quantum Darwinism
PublikacjaQuantum Darwinism posits that only specific information about a quantum system that is redundantly proliferated to many parts of its environment becomes accessible and objective, leading to the emergence of classical reality. However, it is not clear under what conditions this mechanism holds true. Here we prove that the emergence of classical features along the lines of quantum Darwinism is a general feature of any quantum dynamics:...
-
A large family of filled skutterudites stabilized by electron count
PublikacjaThe Zintl concept is important in solid-state chemistry to explain how some compounds that combine electropositive and main group elements can be stable at formulas that at their simplest level do not make any sense. The electronegative elements in such compounds form a polyatomic electron-accepting molecule inside the solid, a ‘polyanion’, that fills its available energy states with electrons from the electropositive elements...
-
Heterogeneous distribution of surface electrochemical activity in polycrystalline highly boron-doped diamond electrodes under deep anodic polarization
PublikacjaThe surface homogeneity of boron-doped diamond electrodes is variable and depends on anodic polarization conditions. The differentiation factor is the gradual and localized change in surface termination. A series of measurements under different polarization conditions was performed in order to investigate the scale of this effect. Nanoscale impedance microscopy (NIM) revealed large variation of surface resistance in individual...
-
Integration of protein tethering in a rapid and label-free SERS screening platform for drugs of abuse
PublikacjaSurface enhanced Raman spectroscopy (SERS) has emerged as a promising technique for the rapid and ultrasensitive detection of molecular species such as drugs of abuse in biofluids. Yet, it remains a significant challenge to create a viable screening tool for multiple drug classes, owing to the lack of affinity of certain species for the SERS substrate and to the matrix interference in complex media. Here we report a protein tethering...
-
Realistic noise-tolerant randomness amplification using finite number of devices
PublikacjaRandomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification...
-
DNA methylation as a mediator of HLA-DRB1*15:01 and a protective variant in multiple sclerosis
PublikacjaThe human leukocyte antigen (HLA) haplotype DRB1*15:01 is the major risk factor for multiple sclerosis (MS). Here, we find that DRB1*15:01 is hypomethylated and predominantly expressed in monocytes among carriers of DRB1*15:01. A differentially methylated region (DMR) encompassing HLA-DRB1 exon 2 is particularly affected and displays methylation-sensitive regulatory properties in vitro. Causal inference and Mendelian randomization...
-
Review on Wikification methods
PublikacjaThe paper reviews methods on automatic annotation of texts with Wikipedia entries. The process, called Wikification aims at building references between concepts identified in the text and Wikipedia articles. Wikification finds many applications, especially in text representation, where it enables one to capture the semantic similarity of the documents. Also, it can be considered as automatic tagging of the text. We describe typical...
-
Metal ion directed template synthesis using 2-acetyl-1,3-indandione and ethylenediamine: steric and electronic restrictions
PublikacjaA template synthesis using 2-acetyl-1,3-indandione and ethylenediamine results in formation of octahedral Ni complex, whose crystal structure has been resolved using single crystal X-ray diffraction. The structure indicates that only exocyclic enolic oxygen atom of the triketone takes part in the condensation with ethylenediamine.
-
Electromagnetic Simulation with 3D FEM for Design Automation in 5G Era
PublikacjaElectromagnetic simulation and electronic design automation (EDA) play an important role in the design of 5G antennas and radio chips. The simulation challenges include electromagnetic effects and long simulation time and this paper focuses on simulation software based on finite-element method (FEM). The state-of-the-art EDA software using novel computational techniques based on FEM can not only accelerate numerical analysis, but...
-
Differential analysis of dynamic immittance spectra
PublikacjaThis work presents a new approach to the analysis of immittance spectrograms of systems characterised by non-stationarity. The possibility of linking the evolution of the immittance response with changes in the parameters describing the system is achieved by introducing a spectrum in differential form. By using the above procedure, it becomes possible to separate elements with a dependence (or lack thereof) from an independent...
-
Oxidation step in the preparation of benzocamalexin: The crystallographic evidence
PublikacjaThe study of oxidation step in the preparation of benzocamalexin by the α-amidoalkylation–oxidation sequence revealed the formation of perchloro-1,2-phenylene dibenzoate as the product of transformation of tetrachloro- 1,2-benzoquinone applied as the oxidant. The structures of benzocamalexin and perchloro-1,2-phenylene dibenzoate were confirmed by X-ray diffraction analysis. The extraction step in the final isolation of benzocamalexin...
-
Atom-economic thiophosphoroselenenylations of C–H acid esters and amides
PublikacjaThree improved thiophosphoroselenenylation procedures of CHacids, including derivatives of malonic and acetyl-, phosphono-, 4-nitrophenyl- and 3-pyridylacetic acids, have been described and compared to previously reported thiophosphoroselenylation of diethyl malonate using bis(disopropoxyphosphinothioyl)diselenide alone or with the aid of methyl iodide. The use of iodine makes it possible to utilize both equivalents of the selenenylating...
-
Polynomial analysis as a new way of describing dynamic impedance spectra – Differential and relative impedance spectra
PublikacjaModel measurements of an equivalent electrical system were carried out using the technique of Dynamic Electrochemical Impedance Spectroscopy. The measurement took the form of potentiodynamic changes imposed on the tested system. Using the possibility of continuous impedance measurements, an attempt was made to develop an original and innovative method of analyzing impedance spectrograms, which is termed polynomial analysis. As...
-
Polynomial description of dynamic impedance spectrogram—introduction to a new impedance analysis method
PublikacjaThis paper presents a polynomial description of spectrograms obtained using Dynamic Electrochemical Impedance Spectroscopy. A method to fit the polynomial degree correctly is discussed. A simple electrical system of a diode connected in parallel with a capacitor was used for testing. Dynamic impedance measurements during potentiodynamic polarization were conducted. This paper presents an alternative analysis method that allows...
-
Bi-based halide perovskites: Stability and opportunities in the photocatalytic approach for hydrogen evolution
PublikacjaIn this study, we successfully prepared Bi-based single perovskites of the A3Bi2I9 type (A = Cs, Rb, MA, FA), and, for the first time, attempted to experimentally obtain double perovskites Cs2B’BiI6 type (B′ = Ag, Au, In, Cu). Despite the premises available in theoretical studies, our research has proven the impossibility of the existence of double perovskites of this type. Nevertheless, both types of obtained materials were subjected...
-
Effect of coarse grain aggregate on strength parameters of two-stage concrete
Publikacja. Two-stage concrete (TSC) is a special type of concrete that the method of its construction and implementation is different from conventional one. In TSC, coarse aggregate particles are first placed in the formwork and voids between them are subsequently injected with a special cementations mixture. TSC has been successfully used in many applications, such as underwater construction, casting concrete sections congested with reinforcement...
-
Shipping Low Frequency Noise and Its Propagation in Shallow Water
PublikacjaOne of the most significant factor influencing acoustical climate of the sea is underwater noise generated by moving ships. If the considered sea area has features of the shallow water, namely the wave frequency fulfils relation f < 10c/h, where c denotes phase speed of sound, and h is depths of the sea, then in certain distance from the wave source specific image of sound pressure distribution in the mean of wave modes appears....
-
CROWDSOURCING A KOMUNIKACJA Z KONSUMENTAMI
PublikacjaRozdział prezentuje wybrane modele komunikacji w Internecie oraz crowdsourcing jako nową metodę pozyskiwania pomysłów i informacji od konsumentów. W ciągu ostatnich 5 lat rozwój technologii komunikacyjnych znacząco zmienił sposób komunikowania się ludzi, a w konsekwencji również organizacji z konsumentami. Nie tylko firmy z branży IT mogą wzmocnić swoją markę, reputację oraz zwiększyć przychody dzięki opracowaniu atrakcyjnej, społecznie...
-
The Impact of Information and Communication Technology on the Rise of Urban Social Movements in Poland
PublikacjaThe chapter examines the relationship between the use of Information and Communications Technology (ITC) and the emergence of social movements focused on urban agenda in Poland. The aim is to investigate how and to what extent a growing body of smaller activist groups use opportunities provided by the ITC to achieve their political objectives. The research results indicate that Web-based media have helped to raise the profile...
-
Rola przekształceń styku lądu i wody w procesach rewitalizacji
PublikacjaArtykuł poświęcony jest zweryfikowaniu roli, jaką pełnią przekształcenia granic miedzy lądem i wodą w procesach rewitalizacji. Analizując szereg tego typu działań, w szczególności dotyczących transformacji obszarów poprzemysłowych, można zauważyć, że w ostatnim czasie charakterystyczne dla nich stają się modyfikacje planów obszarów wodnych i form ich granic. Jak okazuje się, działania takie mają nie tylko znaczenie kompozycyjne...
-
Comparison of Doppler Effect Estimation Methods for MFSK Transmission in Multipath Hydroacoustic Channel
PublikacjaUnderwater wireless communication remains a challenging topic, particularly for applications such as wreck penetration where multipath and Doppler effects are very intense. These effects are becoming even more difficult to mitigate for fast data transmission systems that utilize wideband signals. Due to the low propagation speed of acoustic wave in the water, there is a significant difference between the Doppler shift for lower...
-
Using angular dependence of multibeam echo features in seabed classification
PublikacjaThe new approach to seabed classification based on processing multibeam sonar echoes is presented. The multibeam sonars, besides their well verified and widely used applications like high resolution bathymetry measurements or underwater object imaging, are also the promising tool in seafloor identification and classification, having several advantages over conventional single beam echosounders. The proposed seabed classification...
-
Application of Shape From Shading Technique for Side Scan Sonar Images
PublikacjaSide scan sonar (SSS) is one of the most widely used imaging systems in the underwater environment. It is relatively cheap and easy to deploy in comparison with more powerful sensors like multibeam echosounder or synthetic aperture sonar. Although, the SSS does not provide directly the seafloor bathymetry measurements. Its outputs are usually in a form of grey level acoustic images of seafloor. However, the analysis of such images...
-
Sensors and System for Vehicle Navigation
PublikacjaIn recent years, vehicle navigation, in particular autonomous navigation, has been at the center of several major developments, both in civilian and defense applications. New technologies, such as multisensory data fusion, big data processing, or deep learning, are changing the quality of areas of applications, improving the sensors and systems used. Recently, the influence of artificial intelligence on sensor data processing and...
-
Maximizing SDN resilience to node‐targeted attacks through joint optimization of the primary and backup controllers placements
PublikacjaIn Software Defined Networks (SDN) packet data switches are configured by a limited number of SDN controllers, which respond to queries for packet forwarding decisions from the switches. To enable optimal control of switches in real time the placement of controllers at network nodes must guarantee that the controller-to-controller and switch-to-controller communications delays are bounded. Apart from the primary controllers that...
-
Influence of User Mobility and Antenna Placement on System Loss in B2B Networks
PublikacjaIn this paper, the influence of user mobility and on-body antenna placement on system loss in body-to-body communications in indoor and outdoor environments and different mobility scenarios is studied, based on system loss measurements at 2.45 GHz. The novelty of this work lies on the proposal of a classification model to characterise the effect of user mobility and path visibility on system loss, allowing to identify the best...
-
A Survey of Vehicular Network Systems for Road Traffic Management
PublikacjaIn this survey, we analyze the proposals of vehicular communication systems in the context of road traffic management. Starting with the definition of communications between vehicles (V2V), vehicles-to-infrastructure (V2I) and vehicles-to-everything (V2X), we first focus on the requirements and current standards for the Intelligent Transport Systems (ITS), including the maximum communication delay, the communication range and the...
-
Algorytmy samostabilizujące w sieciach o wybranych topologiach
PublikacjaIdea algorytmów samostabilizujących została zapoczątkowana przez E. Dijkstrę artykułem pt. „Self-stabilizing systems in spite of distributed control” (Communications of the ACM, 1974). W rozprawie został położony nacisk na algorytmy samostabilizujące działające w sieciach o pewnych specyficznych topologiach, jak na przykład w grafach maksymalnych zewnętrznie planarnych, iloczynach kartezjańskich tych grafów ze ścieżkami i w drzewach. Wykorzystując...
-
Advantages of the Application of the Temper Bead Welding Technique During Wet Welding
PublikacjaThermo-mechanically rolled S460ML steel was chosen for welding in underwater wet welding conditions by covered electrodes. The main aim of this study was to check the weldability for fillet welds in a water environment by controlled thermal severity (CTS) tests and to check the influence of temper bead welding (TBW) on the weldability of the investigated steel. Non-destructive and destructive tests showed that S460ML steel has...
-
A novel architecture for e-learning knowledge assessment systems
PublikacjaIn this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products....
-
A novel architecture for e-learning knowledge assessment systems
PublikacjaIn this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products....
-
A novel architecture for e-learning knowledge assessment systems
PublikacjaAbstract. In this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture,while well suited for didactic content distribution systems is ill-suited for knowledge assessment...
-
Path Loss Analysis in Off-Body Channels in Indoor Environment
PublikacjaThis temporary document describes an analysis of path loss in off-body channels in an indoor environment. The influence of body orientation and on-body antenna placement on path loss in off-body communications as well as of different bodies has been investigated. Five static scenarios, six distances between body and antenna and eight body orientations were analysed; moreover, two dynamic scenarios were investigated. The smallest...
-
A Highly Scalable, Modular Architecture for Computer Aided Assessment e-Learning Systems
PublikacjaIn this chapter, the authors propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. The authors' research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge...