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określenia odporności tego typu betonów na korozję chlorkową. Celem niniejszej pracy było zbadanie zjawisk migracji i wiązania jonów chlorkowych w betonie z recyklingu narażonym na korozję mrozową w środowisku soli. Mikrostrukturę betonu z recyklingu oceniono z wykorzystaniem skaningowej mikroskopii elektronowej [SEM], a proces migracji jonów chlorkowych zasymulowano z wykorzystaniem oprogramowania komputerowego COMSOL. Wyniki wskazują, że w przypadku betonów z kruszywem z recyklingu poddanych badaniu mrozoodporności w 3% roztworze NaCl, uszkodzenia wynikające z korozji mrozowej są poważniejsze niż w przypadku próbek zanurzonych w wodzie. Zawartość wolnych jonów chlorkowych w betonach z recyklingu poddanych cyklicznemu zamrażaniu i rozmrażaniu w wodzie w minimalnym stopniu zależała od zawartości popiołu lotnego [NF] i stopnia zastąpienia naturalnego kruszywa grubego [NCA] kruszywem grubym pochodzącym z recyklingu [RCA]. Gdy cykle zamrażania i rozmrażania prowadzono w 3% roztworze NaCl, zwiększenie zawartości popiołu lotnego w mieszance przy stałym udziale kruszywa RCA skutkowało najpierw zmniejszeniem, a następnie wzrostem zawartości wolnych jonów chlorkowych oraz zdolności wiązania jonów chlorkowych w betonie. Beton z recyklingu zawierający w spoiwie 15% popiołu lotnego [NF] cechował się lepszą odpornością na korozję mrozową w obecności soli od betonu pozbawionego popiołu NF oraz betonu zawierającego ultradrobny popiół lotny [SF]. Wraz ze wzrostem udziału kruszywa z recyklingu, zawartość wolnych jonów chlorkowych wzrastała, a odporność na korozję chlorkową betonu z recyklingu ulegała pogorszeniu. Korzystając z drugiego prawa Ficka, współczynnik dyfuzji jonów chlorkowych obliczono za pomocą oprogramowania MATLAB, a następnie w programie COMSOL dokonano symulacji, która dobrze odzwierciedla mechanizm dyfuzji chlorków w betonie z recyklingu.
the use of recycled aggregate produced from waste concrete. The objective of this paper is to investigate the migration behaviors and binding characteristics of chloride ions in recycled concrete, which were exposed to the salt-freezing coupling environment. The microstructure of the recycled concrete was conducted through scanning electron microscope (SEM), while the process of chloride ions migration was simulated by COMSOL software. The results indicated that the degree of recycled concrete, prepared by recycled coarse aggregate [RCA] and different particle size fly ash [NF], frost damage was higher in a 3 % NaCl solution compared to water. The contents of free chloride ions in recycled concrete subjected to freezing-thawing [F-T] cycle in water was minimally influenced by the NF content or the replacement rate of RCA. Under F-T conditions in a 3 % NaCl solution, increasing the NF content at the same replacement rate of RCA results in a decreasing-then-increasing trend in both the free chloride ion content and the chloride ion binding capacity in the concrete. Recycled concrete containing 15 % NF had a superior salt frost resistance compared to recycled concrete without NF or with ultrafine fly ash [SF]. With the replacement rates of RCA increasing, the contents of free chloride ions rose, the salt resistance of recycled concrete decreased. Using Fick’s second law, the chloride ion diffusion coefficient was calculated using MATLAB, and COMSOL software simulation accurately portrayed the diffusion state of free chloride ions in the recycled concrete.
Subsequently, H-bonds in six uracil – water complexes are analyzed. The influence of dispersion interactions and the polar environment on the hydrogen bond energy was analyzed. Results obtained by B3LYP functional with and without Grimme D3 dispersion correction indicate that dispersion interaction plays a significant role in an association process. In addition, the polar solvent reduces the hydrogen bond energy and this reduction is directly proportional to the hydrogen bond energy.
Lewicka-Kamińska, the fruit of which were previously unknown editions of the popular prayer book Hortulus animae, found and preserved only in the fragments they discovered. The most groundbreaking was Nehring’s find, thanks to which eight pages of the first Polish edition of Hortulus were published, but the importance of the remaining ones cannot be overestimated. It is noteworthy that out of eleven (certain and highly probable) editions, dating back to the first half of the 16th c., as many as six are known only thanks to single sheets extracted from their bindings.
dimethyl ethyl benzyl ammonium chloride–TDEBAC) to sodium montmorillonite (Na-MMT) with various cation exchange capacities (CEC) was investigated by using Molecular Dynamics (MD) simulation. In the simulations, as in the experimental studies, it was revealed that the surfactants were both adsorbed on to basal surfaces and settled between the layers. From the morphological analysis obtained from MD simulations, it was calculated that the inter-molecular interaction between the layers was higher than on the basal surface. For example, for the model with 118 CEC motif, the binding energy of all three surfactants in the models with the hydrophilic heads facing the same direction was calculated as -678.18 kcal/mol at the basal surface, while this value was found to be -688.90 kcal/mol in the interlayer. The more striking result is that in the simulations made by turning the head of the middle one of the three surfactants towards the tails of the right and left ones, only -34.86 kcal/mol binding energy was calculated on the basal surface, while this value was -525.63 kcal/mol in the interlayer. As compared middle reversed surfactant models with the same direction ones, despite increased CEC the intermolecular interaction decreased for the basal surface, but the interaction increased between the layers.
granitowej w porównaniu z cementem. Gęstość objętościowa próbki referencyjnej jest mniejsza niż próbek z mączką granitową. Ponadto dodatek mączki granitowej skraca proces wiązania o ok. 25 min i ma pozytywny wpływ na temperaturę świeżej zaprawy w porównaniu z próbką referencyjną. Powoduje jej obniżenie, co może ułatwić proces betonowania w warunkach letnich. Częściowa zamiana cementu mączką granitową powoduje zmniejszenie wytrzymałości na ściskanie do 6% oraz wytrzymałości na rozciąganie przy zginaniu do 18,7% w porównaniu z próbką referencyjną.
specific surface area of granite powder grains compared to cement. The volume density of the reference sample is lower than that of the samples with granite powder. The addition of granite powder shortens the setting process by 25 minutes, compared to the reference sample and has a positive effect on the temperature of the fresh mortar by lowering it, which may have a positive effect on the concreting process in summer conditions. Partial replacement of cement with granite powder results in a reduction up to 6% of the compressive strength compared to the reference sample and a reduction of up to 18.7% of the bending tensile strength.
skonstruowania.
applications in the data transmission networks. In this paper, we investigate the rela- tionship between the binding numbers of graphs and the fractional ID-[a, b]-factor-critical covered graphs, and derive a binding number condition for a graph to be fractional ID-[a, b]-factor-critical covered, which is an extension of Zhou’s previous result [S. Zhou, Binding numbers for fractional ID-k-factor-critical graphs, Acta Mathematica Sinica, English Series 30(1)(2014)181–186].
problematykę powstawania, składowania i neutralizacji odpadów promieniotwórczych. Następnie krótko scharakteryzowano największe awarie elektrowni jądrowych na świecie i ich skutki, ponieważ awarie te miały silny wpływ na decyzje o zamknięciu lub nawet zaniechaniu budowy takich elektrowni. Jednak wdrożenie nowych rozwiązań w budowie reaktorów jądrowych, opartych na wnioskach z poprzednich awarii, znacznie ogranicza możliwość wystąpienia tego typów awarii w przyszłości. Na koniec autor omawia kwestię budowy elektrowni jądrowych w Polsce, wskazując na fakt eliminacji węgla i gazu z produkcji energii elektrycznej w celu ograniczenia emisji CO2. Konieczność budowy elektrowni jądrowej wynika również z faktu, że energia pozyskiwana z tzw. odnawialnych źródeł energii nie zaspokoi w pełni zapotrzebowania na energię, jednak przed rozpoczęciem jej budowy w Polsce należy rozwiązać kilka problemów.
problem of radioactive waste generation, neutralization and storage is discussed. Next, the largest failures of nuclear power plants and their effects were briefly characterized, since such accidents had a strong impact on decisions to close or even abandon the construction of such power plants. However, the implementation of new solutions in the construction of nuclear reactors, based on the conclusions of previous accidents, significantly reduces the possibility of their occurrence in the future. Finally, the author discuss the issue of construction of nuclear power plants in Poland pointing to the fact of elimination coal and gas from electricity production in order to reduce CO2 emission. This is motivated by the fact that energy obtained from the so-called renewable energy sources will not fully meet the energy demand. However, a few problems should be solved before starting the construction of a nuclear power plant in Poland.
jonów metalu gościa monitorowano za pomocą spektroskopii elektronowej absorpcyjnej i emisyjnej, wyznaczając stałe stabilności kompleksowania 1:1 w roztworach aprotycznych i protofilowych. Kompleksy oksa-tia-koronowe C₄₀H₄₀F₁₂N₆O₂P₂RuS₃ (II) i C₅₆H₅₄BF₄N₂O₂P₂S₃Cu·CH₂C₁₂ (III) wykazywały wyższą zdolność wiązania jonów metali przejściowych niż jonów metali alkalicznych i ziem alkalicznych, podczas gdy kompleks C₄₀H₄₀F₁₂N₆O₅P₂Ru (I) nie wykazywał żadnej zdolności wiązania kationów. Tak więc kompleksy z miękkimi donorami w cząsteczkach koronowych były odpowiednie dla miękkich kationów gościa, szczególnie dla kationów Hg(II).
electronic absorption and emission spectroscopies and thus the stability constants for 1:1 complexation were detd. in aprotic and protophilic solns. The oxa-thia-crown-containing complexes C₄₀H₄₀F₁₂N₆O₂P₂RuS₃ and C₅₆H₅₄BF₄N₂O₂P₂S₃Cu·CH₂Cl₂ exhibited higher binding performance towards transition metal ions than towards alkali or alkaline earth metal ions. The complex C₄₀H₄₀F₁₂N₆O₅P₂Ru did not show any cation-binding ability. Thus, the complexes with soft donors in the crown moieties were applicable for soft guest cations especially for Hg(II) ones.
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as an indicator was introduced to combine with plant-esterase. The time of reach equilibrium in PBS solution was shortened after adding plant-esterase by assaying the intensify change of the porphyrin spectrum. Meanwhile, intensify of porphyrin spectrum with plant-esterase was increased compared with that of only the porphyrin spectrum in solution. Tetraphenyl metal porphyrin, such as cobalt(II) meso-tetraphenyl porphyrin, is a mixed reversible inhibitor of plant-esterase from kinetic parameters. The combination ratio of plant-esterase and porphyrin is 2:1. On the other hand, the interaction between CoTPPCl and plant-esterase is the strongest among all tested tetraphenyl metal porphyrin. And the mixed system (CoTPPCl-plant-esterase) showed the best sensitivity towards the tested pesticide. All these results indicated that a complex system composed of tetraphenyl metal porphyrin and plant-esterase was fit for detecting pesticides. They make meaningful guidance on the further design of sensing material in monitoring pesticides.
was intended to counteract. Since May 2018, the transfer of data to third countries can only take place in full compliance with the General Data Protection Regulation. However, in addition to this EU regulation, a number of regulations relating to the processing of passenger name record have been developed in the European Union. The aim of this article is to present these regulations and to show the impact of GDPR on them.
historycznych budynków murowanych na trzęsienia ziemi, jest szczegółowa informacja o takich budynkach. Dlatego też ta praca ma na celu zbadanie właściwości materiałowych historycznego budynku na podstawie badania substancji nierozpuszczalnych w kwasie, oceny pH i przewodnictwa elektrycznego. Ponadto zastosowano rentgenowską spektrometrię fluorescencyjną [XRF] i dyfrakcję rentgenowską [XRD] oraz analizę termiczną [TG/ DTG], a także petrograficzną, w celu oznaczenia składu fazowego. Oznaczono także gęstość, masową absorpcję wody, objętościową absorpcję wody, gęstość właściwą, porowatość oraz zbadano wytrzymałość pod obciążeniem jednoosiowym. Ustalono, że występujące większe wtrącenia są kwarcytem, który jest skałą metamorficzną o dużej wytrzymałości na ściskanie, składającą się z minerałów bogatych w krzemionkę. Badane zaprawy murarskie nie wykazują właściwości hydraulicznych, kruszywo nie ma właściwości pucolanowych, a materiałem wiążącym stosowanym w zaprawach, jest stosunkowo czyste wapno.
detailed information about such buildings. Therefore, this study aims to investigate material properties of a historical building by means of acid loss, pH, electrical conductivity, X-ray fluorescence spectrometry [XRF], thermal analysis [TG/DTG], petrographic analysis, X-ray diffraction [XRD], density, mass water absorption, volume water absorption, specific mass, porosity and uniaxial loading tests. It has been determined that stones are quartzite, which is a metamorphic rock with high compressive strength, composed of quartz minerals. Examined masonry mortar does not show hydraulic properties, the aggregates are not pozzolanic aggregates and the binder material used in mortars is pure lime.
structural polymorphism in aqueous media. In parallel, a great number of GQ structures have been extensively surveyed ex vivo by means of biophysical techniques such as nuclear magnetic resonance (NMR) spectroscopy, circular dichroism (CD) spectroscopy, and X-ray crystallography. Accumulating evidence suggesting that G-quadruplexes play essential role in a numerous biological processes in vivo, including DNA replication and transcription, RNA translation as well as genomic maintenance. Consequently, G-quadruplexes has attracted attention as therapeutic targets in cancer or hereditary diseases as well as molecular target in cellular biology. Study on G-quadruplexes:ligand interaction by NMR, CD, UV and fluorescence spectroscopy in vitro or in vivo has become an intensive research work area of many groups in recent years. Nowadays, there are available large amount of organic compounds that selectively bind to G-quadruplexes and their photophysical and kinetic properties were comprehensively characterized but only few of them are endowed with fluorescence properties that could be applicable as fluorescent probes in cellular biology or in vitro detection. Interestingly, the group of these fluorescent probes is characterized by a vast structural diverisity resulting from the different way of interaction with G-quadruplexes as well as G-quadruplex polymorphism. This review focuses on the G-quadruplex-selective light up fluorescent probes that have been employed for in vitro detection as well as cellular imaging along with a summary of the key photophysical, biophysical, and biological properties of reported examples.
uzbrojenia wielokrotnie regenerowanego silikażelu. W ramach pracy określono maksymalną chłonności pochłaniaczy wilgoci dla różnych warunków klimatycznych, minimalny poziom wilgotności względnej (RH) w osuszanej komorze pomiarowej dla różnych ilości absorbentu oraz trwałości wiązania wody w zmiennych warunkach temperaturowych. Analiza otrzymanych wyników pozwoliła porównać rodzaje absorbentów określić ich zalety i wady oraz pozwoliła ocenić stopień zużycia aktualnie eksploatowanego absorbentu wilgoci w sprzęcie uzbrojenia.
gel currently deployed inweapon systems. As part of the work, the maximum absorbency of moisture absorbers for various climatic conditions, the minimum relative humidity (RH) in the drying measuring chamber for various amounts of absorbent, and the durability of water binding at variable temperature conditions were determined. Analysis of results allowed both to compare advantages and disadvantages of various absorbents, and to assess a degree of the wear for moisture absorbents currently used in armament equipment.
particularly in areas as Robotics, Self-Adaptive Systems, IoT, CPS, AI-Hardware, etc. At the modelling, conceptual level our main contribution is the introduction of the concept of "virtual organism" (VO), to populate the intermediary level between reconfigurable hardware agents and intelligent, adaptive software agents. A virtual organism has a structure, resembling the hardware capabilities, and it runs low-level functions, implementing the software requirements. The model is compositional in space (allowing the virtual organisms to aggregate into larger organisms) and in time (allowing the virtual organisms to get composed functionalities). The virtual organisms studied here are in 2D (two dimensions) and their structures are described by 2D patterns (adding time, we get a 3D model). By reconfiguration an organism may change its structure to another structure in the same 2D pattern. We illustrate the VO concept with a few increasingly more complex VO's dealing with flow management or a publisher-subscriber mechanism for handling services. We implemented a simulator for a VO, collecting flow over a tree-structure (TC-VO), and the quantitative results show reconfigurable structures are better suited than fixed structures in dynamically changing environments. Finally, we briefly show how Agapia - a structured parallel, interactive programming language where dataflow and control flow structures can be freely mixed - may be used for getting quick implementations for VO's simulation.
Elemental composition of gypsum kinds were carried out using a scanning electron microscope (SEM) with EDS/EDX probe, their crystal structure and phase composition was determined by analyzing the results of X-ray diffraction measurements (XRD) and thermogravimetric studies (TG-DTA). Evaluation of the mechanical properties of selected materials was carried out at the tensile strength test of the dog-bone samples after initial hardening of gypsum mortar at 25°C for 5 h and drying at 110°C for 24 hours. The impact of the properties of the used commercial gypsum kinds on the possibility of their use as a valuable binders in the manufacture of the foundry sandmixes for moulds and cores was evaluated. Construction gypsum and finishing coat have the highest tensile strength. Plaster gypsum and finishing coat have the longest setting time. In all tested types of gypsum, the initial water loss during heating occurs at a temperature of about 200°C. The lowest valuable properties as a binder for sand moulding mixtures has jewelry casting gypsum mass.
disease, which affects tens of millions of patients worldwide. The amyloid cascade prevails among a variety of possible mechanisms of its development proposed in the scientific literature. It proposes that death of neurons, preceded by dysfunction of their synaptic activity is caused by the incremental formation of structures (fibrils, oligomers) composed of Aβ peptides. In its copper variant the processes of aggregation and oxidative stress, causing the inflammation and neuronal damage are related to the formation of reactive Cu(II) complexes with Aβ peptides. Aβ peptides are a family of molecules with similar amino acid sequences, differing mainly by the presence of longer or shorter terminal sequences. Their physiological role of is unclear. Aβ1-42 and Aβ1-40 have been mostly studied, but most studies have ignored a very abundant N-terminally truncated species Aβ4-42. We recognized it, and more gene-rally the Aβ4-x peptide family as potentially strong Cu(II) ligands, due to the presence at their N-termini of the Phe-Arg-His amino acid sequence, comprising the ATCUN/NTS structural motif. This observation was followed by vigorous research performed in our laboratory. We studied the ability of Aβ4-x peptides to bind Cu(II) ions, their electrochemical properties and redox reactivity, interactions with proteins which bind copper under physiological conditions, their aggregation properties in the Cu(II) presence and susceptibility to proteolysis. Additionally, we investigated their interaction with a molecule of a therapeutic potential. We demonstrated that Aβ4-x peptides can be primary copper bin-ding agents in extracellular spaces in the brain, able to instantaneously intercept copper from Aβ1-x peptides studied so far. Cu(II) complexes of Aβ4-x peptides are highly resistant to oxidation and reduction, release copper ions to other molecules slowly and reluctantly, and do not produce reactive oxygen species. In accordance with these properties we proposed a physiological role for the Aβ4-42 peptide as a molecule cleansing the synaptic cleft from Cu2+ ions and thereby assuring the correct neurotransmission. This function can however be disturbed by an inappropriate pharmacological intervention. The results of studies of the effect of cupric ions on the aggregation and membrane interactions of the Aβ4-40 peptides suggest that copper can inhibit the Aβ4-x peptides toxicity, thereby providing an additional support for our concept. Studies of hydrolysis of Aβ peptides and properties of its products revealed a possibility for a significant role of short fragments in the brain copper physiology. Our hypothesis awaits verification by biological studies. The issue of metabolism of the studied complexes is a key issue remaining to be solved.
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że materiał pochodzący z obciążonych olejowych płuczek wiertniczych może stać się po obróbce termicznej efektywnym składnikiem zapraw cementowych, wykorzystywanych jako osłony przed promieniowaniem jonizującym. Zaolejone odpady wiertnicze wysuszono w temp. 105°C przez 24 h i następnie w temp. 800°C przez 2 h celem wypalenia związków organicznych. Materiał o uziarnieniu poniżej 0,1 mm dodawano w ilości 25% mas. do cementu portlandzkiego i badano parametry zapraw cementowych. Stwardniałe zaprawy cementowe badano metodą dyfrakcji rentgenowskiej i metodami SEM i porównano z zaprawami referencyjnymi.
cement mortars. The hardened cement mortar was studies by X-ray diffraction anal. and found comparable to ref. mortar.
the binding.
otwierania oprawy.
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