Filters
total: 2151
displaying 1000 best results Help
Search results for: microwave solvothermal synthesis
-
Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences
PublicationNanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...
-
Surface modification of PMMA polymer and its composites with PC61BM fullerene derivative using an atmospheric pressure microwave argon plasma sheet
PublicationThis paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PC61BM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. The experimental parameters were: an argon (Ar) flow rate (up to 20 NL/min), microwave power (up to 530 W), number...
-
Synthesis and properties of carboxy derivative of Epidian 6 monomethacrylate (in English)
PublicationWe present the synthesis of an oligomer with carboxy and methacrylic groups based on Epidian 6. The effect of the catalyst nature and amount, solvent nature and process temperature on the rate of the reaction between Epidian6 monomethacrylate and adipic acid was examined at 313, 323 and 333 K in the presence of 4-dimethylaminopyridine, 1,4-diazobicyclo[2.2.2]octane, and benzyltriammonium chloride. The synthesized oligomer was characterized...
-
Beta-Galactosidases of Pseudoalteromonas sp. – Characteristics and application for lactose hydrolysis and galactopyranosides synthesis
PublicationBeta-galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It has biotechnological applications in the dairy industry for the production of milk with a low content of lactose and galactooligosacharides for use in healthy food. The transgalactosylation activity of beta-galactosidase can be used in the synthesis of alkyl galactopyranosides. Due to the fact that conditions of...
-
4-(Cyclic-amidino)phenols. Preparation and Use in a Diamidine Synthesis
PublicationThe Pinner synthesis was applied to the prepn. of phenols 4-substituted with cyclic amidines in high yields from readily available 4-HOC6H4C(OMe):NH.HCl and aliph. diamines. An alternative attempt was made to convert 4-HOC6H4CSNH2 to 4-(1,4,5,6-tetrahydro-5-hydroxy-2-pyrimidinyl)phenol. A procedure for the prepn. of 3,6-bis(4-hydroxyphenyl)-1,2,4,5-tetrazine is reported. The syntheses of 2,4-bis[4-(4,5-dihydro-1H-imidazol-2-yl)phenoxy]pyrimidine...
-
Synthesis an anglophone journal of comparative literary studies
Journals -
RNS/TCS CONVERTER DESIGN USING HIGH-LEVEL SYNTHESIS IN FPGA
PublicationAn experimental high-level synthesis (HLS) of the residue number system (RNS) to two’s-complement system (TCS) converter in the Vivado Xilinx FPGA environment is shown. The assumed approach makes use of the Chinese Remainder Theorem I (CRT I). The HLS simplifies and accelerates the design and implementation process, moreover the HLS synthesized architecture requires less hardware by about 20% but the operational frequency is smaller...
-
A New Approach to Chemical Recycling of Polyamide 6.6 and Synthesis of Polyurethanes with Recovered Intermediates
PublicationA new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino- glycolysis process. The described process of decomposition did not...
-
Spatial characterization of H 2: CH 4 dissociation level in microwave ECR plasma source by fibre-optic OES
PublicationSpatially resolved optical emission spectroscopy (SR-OES) was used to investigate microwave activated H2/Ar/CH4 plasma under conditions of the electron cyclotron resonance (ECR). The chemistry and composition of the gas phase were studied using self-designed fibre-optic system with echelle type spectrometer during CVD deposition of polycrystalline diamond. One-dimensional intensity profiles of the main species were collected along...
-
Tuning of the Electrochemical Properties of Transparent Fluorine-doped Tin Oxide Electrodes by Microwave Pulsed-plasma Polymerized Allylamine
PublicationWe report here the dry, one-step, and low-temperature modification of FTO surfaces using pulsed plasma polymerization of allylamine (PPAAm). PPAAm/FTO surfaces were characterized by X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and contact angles to understand the morphological, structural, and optical properties. FTO were coated with a very thin layer of adherent cross-linked, pinhole-, and additive-free allylamine...
-
Kinetics study of the fully bio-based poly(propylene succinate) synthesis. Functional group approach
PublicationCurrently, the increasing importance of the bio-based chemical compounds development is visible in the polymer chemistry, chemical engineering and materials science. It is well-known that the various purity level and different contaminants characterize petrochemical-based compounds compared to their biobased counterparts. Therefore, it is necessary to find out the contaminants impact on the bio-based monomers synthesis. One of...
-
Lower-rim-substituted tert-butylcalix[4]arenes. Part IX: one-pot synthesis of calix[4]arene-hydroxamates and calix[4]arene-amides
PublicationZaprezentowano prostą metodę selektywnej acylacji podstawionych i niepodstawionych hydroksyloamin za pomocą di i tetra podstawionych kaliks{4]aren-kwasów. Pokazano pierwszą strukturę krystalograficzną kaliks-hydroksyamidu.
-
An Efficient Framework For Fast Computer Aided Design of Microwave Circuits Based on the Higher-Order 3D Finite-Element Method
PublicationIn this paper, an efficient computational framework for the full-wave design by optimization of complex microwave passive devices, such as antennas, filters, and multiplexers, is described. The framework consists of a computational engine, a 3D object modeler, and a graphical user interface. The computational engine, which is based on a finite element method with curvilinear higher-order tetrahedral elements, is coupled with built-in...
-
Low-cost performance-driven modelling of compact microwave components with two-layer surrogates and gradient kriging
PublicationUtilization of electromagnetic (EM) simulation tools has become indispensable for reliable evaluation of microwave components. As the cost of an individual analysis may already be considerable, the computational overhead associated with EM-driven tasks that require massive simulations (e.g., optimization) may turn prohibitive. One of mitigation methods is the employment of equivalent network models. Yet, they are incapable of accounting...
-
Synthesis of disubstituted 1,3,4,9-tetrahydropyrano-[3,4-b]indole-1-acetic acids derivatives
Publication1,3,4,9-tetrahydropyrano[3,4-b ]indole-1-acetic acid derivatives are of interest for pharmaceutical research as a core structure for synthesis of biological active substance - Etodolac (selective Cyclooxygenase-2 inhibitor, which belongs to the Non-steroidal Anti-inflammatory Drug, NSAID, that shows a clin-ically effective analgesic and anti-inflammatory activity). Here the way of synthesis of two 1,3,4,9-tetrahydropyrano[3,4-b...
-
Surrogate-assisted EM-driven miniaturization of wideband microwave couplers by means of co-simulation low-fidelity models
PublicationThis article proposes a methodology for rapid design optimization of miniaturized wideband couplers. More specifically, a class of circuits is considered, in which conventional transmission lines are replaced by their abbreviated counterparts referred to as slow-wave compact cells. Our focus is on explicit reduction of the structure size as well as on reducing the CPU cost of the design process. For the sake of computational feasibility,...
-
Study of anticorrosion and microwave absorption properties of NiZn ferrite pigments
Publication -
Hydrothermal, microwave and mechanochemical modification of amorphous zirconium phosphate structure
Publication -
Y2O3:Eu nanocrystals as biomarkers prepared by a microwave hydrothermal method
Publication -
A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
PublicationGoal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume...
-
SYNTHESIS OF PHOSPHORUS TACRINE ANALOGUES AS A NEW POTENTIAL ANTI-ALZHEIMER’S DISEASE AGENTS
PublicationA series of novel phosphorus tacrine derivatives was obtained in three steps, including synthesis of 9-chlorotacrine, connection of 9-chlorotacrine with hexamethylenediamine, 1,8-diaminooctane and 1,12-diaminododecane linkers and reaction of obtained tacrine diamine analogues with corresponding acid ester to give nine tacrine organophosphorus compounds. All of the obtained final structures were characterized by 1H NMR, 13C NMR,...
-
A reliable synthesis of discrete-time H-inf control. Part I: basic theorems and J-lossless conjugators
PublicationThe paper gives a basis for solving many problems of numerically reliable synthesis of sub-optimal discrete-time control in H-inf. The approach is based on J-lossless factorisation of the delta-domain chain-scattering description of continuous-time plants being controlled. Relevant properties of poles and zeroes of chain-scattering models are given. Necessary and sufficient conditions for the existence of stabilising J-lossless...
-
Coupled-resonator filters with frequency-dependent couplings: coupling matrix synthesis
Publication -
Influence of synthesis conditions on zinc oxide nanorode layer morphology
PublicationIn recent years one dimensional (1D) nanostructures (nanotubes, nanowires, nanoribbons and nanorods) have been widely studied. Among studied nano-materials, the greatest interest can be seen for zinc oxide (ZnO). However, there is still a need for simple, inexpensive and reproducible fabrication method. In the literature different fabrication methods can be found, most of them requires expensive equipment and involve complex...
-
Synthesis of a state feedback controller for an averaging tank with variable filling
PublicationIn paper, a nonlinear averaging tank with variable filling is considered. The main purpose of this research work was the modelling and control system synthesis of an averaging tank. The control objectives included ensuring stability and zero steady-state error of the system and achieving settling time as short as possible, while maintaining a minimal overshoot. In order to achieve the intended purpose, firstly a mathematical model...
-
Synthesis Methods and Favorable Conditions for Spherical Vaterite Precipitation: A Review
PublicationVaterite is the least thermodynamically stable anhydrous calcium carbonate polymorph. It exists very rare in nature, e.g. in some rock formations or as a component of biominerals produced by some fishes, crustaceans or birds. Synthetic vaterite particles are proposed as carriers of active substances in medicines, additive in cosmetic preparations as well as adsorbents. Also, their utilization as a pump for microfluidic flow is...
-
Emulsifi ers from renewable materials: an eco-friendly synthesis and properties
PublicationThe focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained...
-
Synthesis of malonylenamides and thiomalonylenamides
Publication5-[Hydroksyl(aryl(amino))methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione is convenient source of ketenes which can be trapped with various nucleophiles like alcohols, thiols and amines. In reaction between in situ generated ketene and enolizable imines we can easily obtain corresponding malonylenamides. This facile method can be used to obtain thiomalonylenamides using 5-[sulfhydrylo(alkyl(amino))methylene]-2,2-dimethyl-1,3-dioxane-4,6-dione...
-
Photocatalytic Synthesis of Chemicals
Publication -
Lipopeptides - synthesis and their properties
PublicationPrzedstawiono syntezę nowych peptydów zawierających Hyp, Met, Gly podstawionych w miejscu histydyny tripeptydu o sekwencji Gly-His-Lys oraz ich odpowiednie modyfikacje na N- i C-końcach. Syntezę zaprojektowanych analogów prowadzono na fazie stałej z zastosowaniem procedury Fmoc. Po otrzymaniu zaplanowanego łańcucha peptydowego metodą karbodiimidową (z zastosowaniem DIC oraz HOBt), przystąpiono do wprowadzania na N-koniec glicyny...
-
Electrochemical Synthesis of Photocatalyst
PublicationPonowne wykorzystywanie i recykling fotokatalizatora nanocząsteczkowego jest nie wystarczająco rozwiązanym problem. Powszechnie fotokatalizatory są unieruchomiane przez zol-żel lub zanurzeniowo-powłokowe procedury. Jednak istnieją udokumentowane przypadki wyczerpania fotokatalizatora lub zmniejszenia jego działalności fotokatalitycznej. Synteza elektrochemiczna fotokatalizatora z natychmiastowym unieruchomieniem nie jest własciwie...
-
Lipopeptides - synthesis and their properties
PublicationZaprezentowano syntezę nowych pochodnych tripeptydu Gly-Hyp-Lys o potencjalnie lepszych właściwościach lipofilowych. Modyfikacje polegały na acylowaniu N-końca glicyny kwasami tłuszczowymi (np. palmitynowym i stearynowym). Syntezę lipopeptydów zawierających fragment Gly-X-Y (gdzie: X= Met,Hyp,Hyp-Met,Gly-Hyp; Y=Lys,D-Lys) przeprowadzono na fazie stałej z zastosowaniem procedury Fmoc. Do wydłużanie łańcucha peptydowego zastosowano...
-
Synthesis of adenosine analogues
PublicationAdenozyna jest endogennym nukleozydem purynowym, który nie tylko stanowi prekursor nukleotydów adeninowych, ale jest także neuromodulatorem odgrywającym istotną rolę w funkcjonowaniu wielu komórek. Swoje działanie ujawnia poprzez wiązanie z receptorami dla adenozyny, których zidentyfikowano do tej pory cztery podtypy: A1, A2A, A2B oraz A3. Należą one do rodziny receptorów sprzężonych z białkami G. Adenozyna znalazła zastosowanie...
-
The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
-
On Decision-Making Strategies for Improved-Reliability Size Reduction of Microwave Passives: Intermittent Correction of Equality Constraints and Adaptive Handling of Inequality Constraints
PublicationDesign optimization of passive microwave components is an intricate process, especially if the primary objective is a reduction of the physical size of the structure. The latter has become an important design consideration for a growing number of modern applications (mobile communications, wearable/implantable devices, internet of things), where miniaturization is imperative due to a limited space allocated for the electronic circuitry....
-
Piotr Jamroz dr hab. inż.
PeoplePiotr Jamroz graduated from Wroclaw University of Technology, Faculty of Chemistry in 1998 and obtained his PhD from the same university in 2003. Currently he works as an associate professor at Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy. His research interests are related to generation and diagnostics of different kinds of plasma sources, including...
-
Synthesis and Characterization of Monometallic (Ag, Cu) and Bimetallic Ag-Cu Particles for Antibacterial and Antifungal Applications
PublicationIn this paper, the experimental studies are concerned with the effect of the synthesis parameters on the formation of monometallic Ag and Cu nanoparticles (NPs). We consider the synthesis strategies verification for the bimetallic core-shell and alloy particles preparation. It was successfully obtained by chemical reduction method. The obtained colloidal solution is characterized by the transmission electron microscopy (TEM) with...
-
Cytotoxicity of QDgreen-holo-Tf-C-2028 and QDred-holo-Tf-C-2028 aginst H460 cancer cells_method of synthesis 2
Open Research DataThis study presents absorbance of formazan product (converted from MTT) which corresponds the cytotoxicity of QDgreen-holo-Tf-C-2028 and QDred-holo-Tf-C-2028 aginst H460 cancer cells (method of synthesis 2). Holo-Tf (transferrin) was used as a linker between quantum dots (QDs) and compound (C-2028).
-
Cytotoxicity of QDgreen-holo-Tf-C-2028 and QDred-holo-Tf-C-2028 aginst H460 cancer cells_method of synthesis 3
Open Research DataThis study presents absorbance of formazan product (converted from MTT) which corresponds the cytotoxicity of QDgreen-holo-Tf-C-2028 and QDred-holo-Tf-C-2028 aginst H460 cancer cells (method of synthesis 3). Holo-Tf (transferrin) was used as a linker between quantum dots (QDs) and compound (C-2028).
-
Michał Mrozowski prof. dr hab. inż.
People -
Voiceless Stop Consonant Modelling and Synthesis Framework Based on MISO Dynamic System
PublicationA voiceless stop consonant phoneme modelling and synthesis framework based on a phoneme modelling in low-frequency range and high-frequency range separately is proposed. The phoneme signal is decomposed into the sums of simpler basic components and described as the output of a linear multiple-input and single-output (MISO) system. The impulse response of each channel is a third order quasi-polynomial. Using this framework, the...
-
A new approach to the stereoselective synthesis of trans-3-carbamoyl-b-lactam moieties†
PublicationOne-pot synthesis of optically active 1,4-disubstituted-3-carbamoyl-azetidinones from 5-[(N-arylamino)- (hydroxyl)methylene]-2,2-dimethyl-1,3-dioxa-4,6-diones and chiral aldimines is achieved via thermal generation of carbamoyl ketenes and subsequent [2+2] cycloaddition. Three possible chiral induction approaches were tested and (R)-(+)-1-phenylethylamine was confirmed as the best chiral auxiliary. Among the four possible diastereoisomers,...
-
Phosphate tricyclic coumarin analogs as steroid sulfatase inhibitors: synthesis and biological activity.
PublicationIn the present work, we report convenient methods for the synthesis and biological evaluation of phosphate tricyclic coumarin derivatives as potential steroid sulfatase inhibitors. The described synthesis includes the straightforward preparation of 7-hydroxy-2,3-dihydro-1H-cyclopenta[c]chromen-4-one, 3-hydroxy-7,8,9,10-tetrahydro-6H-benzo[c]chromen-6-one and 3-hydroxy-8,9,10,11-tetrahydro-7H-cyclohepta[c]chromen-6-one modified...
-
Two complementary approaches for the synthesis and isolation of stable phosphanylphosphaalkenes
PublicationPhospha-Wittig (phosphanylphosphinidene titanium(IV) complex) and phospha-Peterson (lithiated diphosphane) reactions were used to obtain phosphanylphosphaalkenes with the general formula XYC=P-PtBu2 (X = alkyl, aryl group or H; Y = alkyl or aryl group). Therefore, two series of reactions with different ketones and aldehydes were performed. An examination revealed that the two methods are complementary. For smaller carbonyl compounds,...
-
A study of the kinetics of bismuth telluride synthesis by an oxide reduction method
PublicationThe kinetics of a reduction of bismuth and tellurium oxides in a hydrogen atmosphere, leading to the formation of thermoelectric bismuth telluride is investigated. The evaluation of the reaction kinetics was based on a thermogravimetric analysis performed in non-isothermal conditions. A non-parametric analysis method and the Friedman method were used for the evaluation of the data. Additionally, for a better understanding of the...
-
A Green Chemistry "environmentally friendly" approach to the synthesis of chloro-intermediates of ephedrine/pseudoephedrine
PublicationMethylamphetamine is an addictive stimulant drug that strongly activates certain systems in the brain. It is closely related chemically to amphetamine, but the central nervous system effects of methamphetamine are greater. There is much interest in methylamphetamine among scientists and therefore the synthesizes of methylamphetamine and its metabolites are carried out on a large scale in chemical laboratories. Globally, ephedrine...
-
Piotr Sypek dr inż.
PeoplePiotr Sypek received the M.S.E.E. and Ph.D. degrees (with hons.) in microwave engineering from the Gdańsk University of Technology, Gdańsk, Poland, in 2003 and 2012, respectively. He was involved in the design and implementation of parallel algorithms for the formulation and solution of electromagnetic problems executed on CPUs (workstations and clusters) and GPUs. His current research interests include parallel processing in computational...
-
Kinetic analysis of the reduction of a ternary system of Bi, Sb and Te oxides by hydrogen for BiSbTe3 synthesis
PublicationReduction in a hydrogen atmosphere of Bi2O3, Sb2O3 and TeO2 mixes oxides for the synthesis of BiSbTe3 was analysed. The reduction reactions of Sb2O3 and Sb2O4 oxides, as well as Bi2O3+Sb2O3 and Sb2O3+3TeO2 mix- tures, were also evaluated. The reduction of Sb2O4 is investigated for the first time. The reactions of the mixed oxides systems also were not the subject of research so far despite being used for synthesis of the (Bi,Sb)2Te3...
-
Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
-
Expedited Re-Design of Multi-Band Passive Microwave Circuits Using Orthogonal Scaling Directions and Gradient-Based Tuning
PublicationGeometry scaling of microwave circuits is an essential but challenging task. In particular, the employment of a given passive structure in a different application area often requires re-adjustment of the operating frequencies/bands while maintaining top performance. Achieving this necessitates utilization of numerical optimization methods. Nonetheless, if the intended frequencies are distant from the ones at the starting point,...