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1
Content available remote Metanizacja CO₂ na katalizatorach wytworzonych metodą depozycji plazmowej
PL
Przedstawiono wyniki badań metanizacji CO₂ przy użyciu nanokatalizatorów wytworzonych na kantalowych nośnikach strukturalnych za pomocą metody chemicznej depozycji z par związków metaloorganicznych wspomaganej plazmą (PEMOCVD). Wykazano wysoką aktywność katalityczną wytworzonych nanowarstw w reakcji uwodornienia CO₂ do metanu. Na podstawie przeprowadzonych badań stwierdzono możliwość wykorzystania przemysłowego wytworzonych katalizatorów, szczególnie w reaktorach strukturalnych.
EN
New Co and Ru nanocatalysts for methanation of CO₂ were prepd. by plasma-enhanced metal-org. CVD on metallic structural supports. The Co₃O₄ or RuO₂-contg. thin films of the nanocatalysts were used for conversion of CO₂ with H₂ (mole ratio 1:4) to MeH in a gradientless flow reactor at 150-500°C and atm. pressure. The exptl. results revealed a high catalytic activity of the deposited films. The RuO₂ catalyst showed higher activity than the Co₃O₄ one.
EN
The filter materials commonly used in filtration processes consist of nonwoven fabrics made by melt blowing. In order to improve filtration properties they are subjected to various modifications. This paper presents the treatment of polycarbonate nonwovens with lowpressure cold plasma generated by a 13.56 MHz RF discharge using process gases such as Ar and O2. The effectiveness of such treatment was assessed on the basis of results of the penetration of nonwovens by paraffin oil mist as well as the air flow resistance. The effects of plasma on polycarbonate nonwovens, especially on their surface morphology and chemical structure, were evaluated by electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The results indicate that Ar plasma is a good tool for improving the filtration properties of polycarbonate filtering materials. According to these results, the surface roughness plays an important role in the high-efficiency filtration of liquid aerosols with a small increase in air flow resistance.
PL
Materiały filtrujące powszechnie stosowane w procesach filtracji to przede wszystkim włókniny wykonane techniką melt-blown. W celu poprawy ich właściwości filtracyjnych są poddawane różnym modyfikacjom. W artykule przedstawiono obróbkę włókniny poliwęglanowej za pomocą zimnej plazmy niskociśnieniowej RF 13,56 MHz przy użyciu gazów procesowych, takich jak argon (Ar) i tlen (O2). Skuteczność takiej obróbki oceniano na podstawie wyników penetracji aerozolu mgły oleju parafinowego przez włókniny oraz oporów przepływu powietrza. Efekt obróbki plazmowej włóknin otrzymywanych z poliwęglanu, zwłaszcza w ich morfologii powierzchni i struktury chemicznej, badano za pomocą mikroskopii skaningowej (SEM), energetycznie-dyspersyjnej spektroskopii rentgenowskiej (EDX) oraz rentgenowskiej spektroskopii fotoelektronów (XPS). Wyniki wskazują, że plazma w argonie jest dobrym narzędziem do poprawy właściwości filtracyjnych włóknin otrzymywanych z poliwęglanu. Na podstawie tych wyników wykazano, że chropowatość powierzchni odgrywa ważną rolę w wysokiej skuteczności filtracji ciekłych aerozoli z małym wzrostem oporu przepływu powietrza.
PL
Dyrektywa Parlamentu Europejskiego i Rady 2008/98/WE z 19 listopada 2008 r. w sprawie odpadów oraz uchylająca niektóre dyrektywy miała być transponowana do prawa każdego kraju członkowskiego do 12 grudnia 2010 r.
PL
Omówiono nowe mikropalniki zimnej plazmy pracujące pod ciśnieniem atmosferycznym. Szczególną uwagę zwrócono na rozwiązania z wyładowaniem jarzeniowym typu RF, takie jak “igła plazmowa” oraz opracowana i opatentowana ostatnio przez nas “żyletka plazmowa”. Przedstawiono dwa przykłady zastosowań mikroplazmy do obróbki materiałów: w zakresie inżynierii polimerów oraz inżynierii biomedycznej. W pierwszym przykładzie omówiono modyfikację powierzchni elastomerów typu SBS, służącą znacznej poprawie zdolności klejenia tych materiałów, w drugim pokazano działanie mikroplazmy na mikroorganizmy, takie jak komórki grzybów Candida albicans.
EN
A review, with 34 refs., of new constructions and uses of cold plasma jets for rubber surface modification and for  disinfection of materials.
PL
W gospodarce odpadami komunalnymi dużo się zmieniło, i to na dobre. Jednak tempo tych przemian było i nadal jest powolne.
6
Content available remote Dopalanie lotnych związków organicznych na katalizatorach na nośniku siatkowym
PL
Przeprowadzono modelowanie i badania eksperymentalne reaktora katalitycznego do dopalania lotnych związków organicznych (LZO) wypełnionego siatkami katalitycznymi. Katalizator (spinel Co₃O₄) naniesiono na siatki stosując technologię plazmową. Przeprowadzono badania kinetyczne w reaktorze bezgradientowym. Do opisu reaktora zastosowano model przepływu tłokowego. Przeprowadzono eksperymenty dopalania n-heksanu (temp. do 560°C, przepływy do 10 Nm³/h). Rozbieżność eksperymentów w stosunku do przewidywań modelowych nie przekraczała 12%.
EN
The catalyst (spinel Co₃O₄) was deposited by plasma technique. The kinetic studies were performed in a gradientless reactor. The plug-flow reactor model was applied. Exps. were performed for catalytic combustion of n-hexane (temp. up to 560°C, gas stream up to 10 m³/h STP). The validation showed max. error of 12% between model and experiment.
EN
An attempt to replace a wet chemical surface modification of styrene-butadiene elastomers (SBS), improving their adhesion to polyurethane adhesives, with a clean low-pressure plasma technique was undertaken. Investigations were performed on radial styrene-butadiene block copolymer with a styrene-to-butadiene ratio equal to 69:31 wt.% (Finaprene 435). The plasma was generated by an RF discharge (13.56 MHz. plate electrode reactor) in various reaction mixtures (CCl4, CHCl3, O2, CO2) to cerate chlorine (-C-CI) and oxygen functionalities (-OH, >C=O i -COOH) on the elastomer surfaces. The elastomer surfaces were investigated by FTIR spectroscopy, contact angle measurements, and T peel tests. The peel strength for plasma treated samples in many cases is much higher than that for the wet chemical modification. It clearly indicates that the plasma treatment is a very promising method of improving the adhesion properties of SBS elastomers.
9
Content available Cold plasma in the nanotechnology of catalysts
EN
In the paper the preparation of catalysts with the use of cold plasmas is discussed. A special attention is focused on nanocatalysts. In general, there are three main trends in this field: (1) plasma enhanced preparation of ..classical" catalysts, (2) plasma sputtering of catalytically active compounds, especially metal and metal oxide nanoparticles, and (3) plasma-enhanced metal-organic chemical vapor deposition (PEMOCVD) of very thin metal and metal oxide films with specific nanostructure. It is shown that the cold plasma techniques are very effective methods for designing the nanocatalysts with distinct and tunable chemical activity, specificity and selectivity. Finally, our preliminary investigations concerning CoOx catalytic films fabricated by the PEMOCVD method are presented.
10
Content available remote W poszukiwaniu fizykochemicznych podstaw homeopatii
EN
Homeopathy is an alternative medicine system that uses ultra-low doses of substances derived from plants, minerals, or animals for the purpose of stimulating the natural healing response of the body. There are two central tenets, on which homeopathy is based: the law of similars and potentization (dilution and shaking), Despite conventional science's unwillingness to grant homeopathy a serious platform, it is difficult to ignore a subject that has survived 200 years of scientific skepticism and is more and more popular alternative system of medicine, Two main questions, however, accompany the whole history of this complementary method: are homeopathic remedies really effective? And if it is true: what is a mechanism of the homeopathic effects? Homeopathy remedies are prepared in a very specific manner. The original substance, called mother tincture, is progressively diluted in a solvent (water, ethanol) and "potentized" by violent shaking between each dilution. It is obvious that after a definite number of dilutions the obtained solution is statistically unlikely to contain a single molecule of the original compound. Such solutions are called ultra-highly diluted (UHD) solutions. Looking for a scientific basis of homeopathy, it is very important to distinguish between remedies containing a low but real dose of the original substance, for which their efficacy is within the limits of what is today's knowledge, and remedies without molecules of the original compounds (UHD solutions), of which effects (if so) are beyond our understanding. Research on the UHD solutions can roughly be classified into three topics. The first concerns clinical investigations on efficacy of homeopathic remedies and their comparison with placebo. Although a lot of trials and meta-analysis have been performed, the general conclusion is totally ambiguous. The latest reports, however, strongly support the notion that the clinical effects of homeopathy are placebo effects. The second topic includes laboratory research on the biological effects, sometimes called preclinical research. The best-known and the most controversial at the same time results were published in 1988 by Benveniste, a once highly respected immunologist, that advocated the existence of biological effects of UHD solutions. Since then numerous experiments have been carried out on laboratory biological systems. Unfortunately, these studies, just as in the case of clinical research, are far from giving incontrovertible evidence for the UHD effects. Finally, the third research topic, which makes the main subject of this paper, is focused on physical, chemical and physicochemical investigations of the UHD solutions. In general, all these investigations are based on the water memory hypothesis and concentrate on the search for physicochemical differences between the UHD solutions and their "pure" solvents. The authors of this paper present herein all published more significant results concerning physicochemical studies carried out on the UHD solutions and undertake an attempt to answer a question, namely whether there is any evidence, on the basis of these results, that can explicitly prove the water memory effect. The results are collected in a few sections according to physicochemical phenomena. The first of these sections (Section 4.2) is devoted to UV-VIS spectroscopy, and investigations of photoabsorption, photoluminescence and thermoluminescence are discussed. Than the studies of "pure" water and the UHD solutions by IR and Raman spectroscopies are presented. The next section includes findings that are related to NMR spectroscopy. NMR has turned out to be a very useful technique to study of dynamic properties of liquid water. Although the earlier tests showed evident differences between various UHD solutions and their solvents, the recent investigations are not so optimistic giving negative replications. It indicates that the previous NMR results should be thoroughly revisited. Similarly, reanalysis of the results concerning thermo-dynamic study, described in the Section 4.5, is also desirable. These investigations were carried out only by one research team from University of Naples and it has not been replicated by another, more "conventional" way. A large proportion of the work is devoted to electrical properties of the UHD solutions and its comparison to pure water and conventional solutions. In this section (Section 4.6), measurements of the electrical conductivity and capacitance, electrical breakdowns, corona discharges, and electrochemical processes are discussed. It is shown that also in this case we can propose the explanation of the observed effects without invoking the water memory hypothesis. In the last part of the sections, in which we can familiarize with physicochemical investigations on the UHD solutions, very questionable measurements of molecular signals and their transmission by electromagnetic means are reported. This issue is closely connected with "digital biology" - a new controversial of science. Summarizing the mentioned above results of physicochemical investigations we can come to a conclusion that without any doubt in many instances the differences in properties between UHD solutions and their solvents exist. In the light of this fact the crucial problem emerges: is it possible: to explain these differences by "conventional" causes or we have to create a new idea that will transform the face of the science? In Sec. 5 we collect both hypotheses based on well-known phenomena (Sec. 5.1), for example ion extraction from the glass during shaking gas dissolving, native impurities of solvents, mechano-catalytic processes, heterogeneity of solutions, and new but disputed hypotheses (Sec. 5.2) originated from the general conception of water memory. It is shown in the paper that the latter hypotheses do not hold up to criticism provided by the modern established knowledge. It is also concluded that today there is no reason to construct groundbreaking theories and the observed phenomena can be explained by "conventional" way. It is very important to remember the following Aristotle's thought: if we want to accept any truth as the scientific knowledge, it must originate from other truths. .
EN
An attempt to replace a wet chemical modification of styrene-butadiene (SBS) elastomer surfaces to improve their adhesion to polyurethane adhesives, with a clean low-pressure plasma technique has been undertaken. The plasma has been generated by an RF discharge (13.56 MHz, plate electrode reactor) in oxygen (O2) or carbon dioxide (CO2) to create oxygen functionalities (>C=O~, OH~, COOH) on the elastomer surfaces. T-peel tests and FTIR spectroscopy have been utilized to investigate the surfaces. Some investigations of the aging processes taking place after plasma treatments have been also performed. It has been found that an important role in the plasma-improved adhesion is played by the chemical interaction between the modified SBS surfaces and polyurethanes. The peel strength for plasma treated samples in many cases is much higher than that for the wet chemical modification. It clearly indicates that the plasma treatment is a very promising method of improving the adhesion properties of SBS elastomers.
EN
Amorphous hydrogenated germanium oxide films (a-GeXOY:H) fabricated by plasma-assisted chemical vapor deposition (PACVD) from a mixture of oxygen and tetramethylgermane in radio-frequency (13.56 MHz) glow discharge, were investigated. Measurements of electrical conductivity and internal photoemission were carried out. It has been found that the films are amorphous insulators (a-I) with the transport gap of 6.7 eV and the conductivity of the order of 10–14 S/m. To characterize the chemical structure of the films, Raman spectroscopy was used. The main structure of the GeO4 type with low concentration of Ge–Ge and Ge–C bonds has been identified.
PL
Do grupy opakowań wielomateriałowych można zaliczyć zróżnicowaną grupę materiałów opakowaniowych. W przemyśle mleczarskim i przy produkcji soków powszechnie wykorzystuje się kartony do płynnej żywności, w przemyśle spożywczym laminaty z folii, papieru i aluminium (zupki z torebki, opakowania do chipsów), a w przemyśle kosmetycznym i farmaceutycznym również materiały zespolone (reklamówki kremów, worki aseptyczne).
PL
Inżynieria Chemiczna i Procesowastoi obecnie w obliczu wyraźnej transformacji z dyscypliny skupionej na zjawiskach makroskopowych w kierunku interdyscyplinarnej nauki opartej na zjawiskach molekularnych. To molekularne podejście stanowi wyzwanie, którego podjęcie zadecyduje o roli i miejscu tej dyscypliny w XXI wieku.
EN
Recently we hale observed the transformation of the chemical and process engineering from a discipline that largely focused on macroscopic phenomena to one that is more interdisciplinary and molecularly based. This molecular approach presents a challenge, of which taking up will determine the role and place of this discipline in the 21[st] century.
EN
Amorphous hydrogenated carbon-silicon (a-SixCy:H) films were produ- \ ced by plasma enhanced chemical vapor deposition (PECVD) in the audio-frequency (a.f.) three-electrode reactor using tetramethylsilane as a source compound. The negative amplitude of a.f. voltage, V, •., measured on a small electrode, on which the films were deposited, was tnę only operational parameter of the deposition process. Investigations of electrical conductivity, UV VIS optical absorption and Raman scattering were carried out for the films deposited at various V^. It was found that these films are composed of amorphous insulator (a-I) and amorphous semiconductor (a-S) fractions with different electronic structures. On the basis of Raman spectroscopy, it was shown that both sp2 C-C and Si Si bonds are created in the a-S fraction in contrast to the a-I fraction in which C-H groups dominate. A shift of the Si-C band position for a-I and a-S is also observed. Probably, it is connected with a transformation from polymer-like to tetra-hedral glasses structure.
PL
Amorficzne wodorowane cienkie warstwy węgiel-krzem (a-SixCY:H) otrzymywano przez plazmowe osadzane chemiczne z fazy lotnej w zakresie częstości akustycznych (cz.a.) w trój elektrodowym reaktorze z tetra-metylosylanu jako związku wyjściowego. Amplituda ujemna napięcia cz.a. V/j mierzona na małej elektrodzie, na której warstwy były osadzane, była jedynym parametrem zmiennym procesu osadzania. Badania przewodnictwa elektrycznego, absorpcja UV-VIS oraz rozpraszanie Ramana były przeprowadzone dla warstw otrzymanych przy różnych wartościach V,v Stwierdzono, że warstwy te złożone są z części amorficznego izolatora (a-I) i amorficznego półprzewodnika (a-S) o różnych strukturach elektronicznej. W oparciu o spektroskopię Ramana wykazano, że oba wiązania sp2 dla C-C oraz Si-Si powstają w strukturze a-S w przeciwieństwie do struktury a-I, w której dominujągrupy C-H. Obserwuje się także przesunięcie pasma od Si-C przy przejściu od a-I do a-S. Przypuszczalnie jest to wynikiem transformacji struktury szkłopodobnej.
PL
W pracy omówiono szerokie możliwości, jakie daje technika plazmy niskotemperaturowej (nakładanie oraz modyfikacja plazmowa) w zakresie wytwarzania nowych, bardziej wydajnych i selektywnych membran. Zestawiono również procesy membranowe, w których podjęto próby zastosowania takich membran.
EN
In this paper, a review concerning good prospects given by plasma technology (deposition of plasma polymers and plasma modification) for the field of membranes is presented. Various membrane processes, in which plasma prepared membranes can be utilized, are also reviewed.
EN
The paper contains information on the preparation and properties of thin films of amorphous semiconductors doped with electrical and optical centers. The discussed films are fabricated by plasma enhanced chemical vapor co-deposition methods. The main attention is focused on doping with elements of groups III, IV, V and lanthanides. It is shown that the electronic structure of the films can be modified by dopants as a result of both doping and alloying effects. Examples of changes in the type and value of conductivity a and the optical gap EOPT in relation to dopant type and its concentration are presented. In the case of the optical centers, one of the most recently interesting problem - namely the plasma polymers doped with lanthanide atoms - is touched. Finally, a brief survey of the most important applications of doped plasma-deposited amorphous semiconductors is given.
EN
Preliminary investigations on preparation, optical and electrical properties of superlattice structures composed of twin layers of an amorphous semiconductor (a-S) and an amorphous insulator (a-l) were performed. These structures were fabricated in an audio-frequency three-electrode plasma reactor as hydrogenated carbon-germanium films (a-GexCy:H) using as a precursor source the mixture of tetramethylgermanium and argon. The type of deposited material (a-l or a-S) was controlled by the coupling capacitance of the system. It has been proved, by means of ellipsometric measurements, that interfaces between a-l and a-S layers are very sharp and the superlattice structure is well defined. Both „blue shift" of the optical gap and changes of electrical conductivity were observed as a result of the superlattice geometry variation. It is, however, doubtful if these phenomena are connected with the quantum size effects.
PL
Amorficzne warstwy uwodornionego węgla (o-C:H) wytwarzano z par pentanu w trójelektrodowym reaktorze plazmowym z wyładowaniem jarzeniowym o częstotliwości 20 kHz. Przeprowadzono badania przewodnictwa elektrycznego tych warstw. Ustalono, że dominującym mechanizmem przewodnictwa jest generacja Poble'a-Frenkela. Wykazano również brak w badanych warstwach występowania zjawiska przejścia: amorficzny izolator (a-I) - amorficzny półprzewodnik (a-S), obserwowanego we wszystkich innych warstwach wytwarzanych w takich samych warunkach z tctraalkilowych pochodnych wąglowców (Si, Ge, Sn, Pb). Wynik ten pozwoli lepiej zrozumieć naturę przejścia a-I-a-S.
EN
Amorphous films of hydrogenated carbon (a-C:H) generated from pcntanc vapours in tri- electrode plasma reactor with glow discharge with 20 kHz frequency. Electric conductivity of the films has been conducted. It has been determined that Poolc - Frenkcl generation is a dominating mechanism of conductivity. The lack of transfer phenomenon occurrence in investigation films was also determined: amorphous insulator (a-1) amorphous semiconductor (a-S) observed in all other films generated in the same conditions with tctra-alkalinc hydrocarbon derivatives (Si, Gc, Sn, Pb). The result will allow for better under standing of transfer nature a-1 - a- S.
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