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EN
Background: Modern industry is heavily dependent on software. The complexity of designing and developing software is a serious engineering issue. With the growing size of software systems and increase in complexity, inconsistencies arise in software design and intelligent techniques are required to detect and fix inconsistencies. Aim: Current industrial practice of manually detecting inconsistencies is time consuming, error prone and incomplete. Inconsistencies arising as a result of polymorphic object interactions are hard to trace. We propose an approach to detect and fix inconsistencies in polymorphic method invocations in sequence models. Method: A novel intelligent approach based on self regulating particle swarm optimization to solve the inconsistency during software system design is presented. Inconsistency handling is modelled as an optimization problem that uses a maximizing fitness function. The proposed approach also identifies the changes required in the design diagrams to fix the inconsistencies. Result: The method is evaluated on different software design models involving static and dynamic polymorphism and inconsistencies are detected and resolved. Conclusion: Ensuring consistency of design is highly essential to develop quality software and solves a major design issue for practitioners. In addition, our approach helps to reduce the time and cost of developing software.
EN
The novelmachine learning technique Random Forest (RF) was used to test if the genetic differentiation of populations of marine species maybe related to any of the key environmental variables known to shape species distributions. The study was performed in North and Baltic Sea characterized by strong gradients of environmental factors and almost continuous distributions of Mytilus mussel populations. Assessment of the species identity was performed using four nuclear DNA markers, and previously published single nucleotide polymorphism (SNP) data. A general pattern of cline variation was observed with increasing Mytilus trossulus share towards the eastern Baltic Sea. Average allele share rose to 61% in Höga Kusten, Gulf of Bothnia. All Baltic Sea samples revealed a strong introgression of Mytilus edulis and a limited introgression of M. trossulus through the Danish Straits. The studied environmental variables described 67 and 68% of the variability in the allele frequencies of M. edulis and M. trossulus. Salinity defined over 50% of the variability in the gene frequencies of the studied Mytilus spp. populations. Changes along this environmental gradient were not gradual but instead a significant shift from gene dominance was found at a salinity of 12 PSU. Water temperature and the trophic status of the sea area had only moderate association with the gene frequencies. The obtained results showed that the novel machine learning technique can be successfully used for finding correlations between genetic differentiation of populations and environmental variables and for defining the functional form of these linkages.
EN
Stachys annua is a short-lived archaeophyte. In Poland it has been classified as threatened with extinction (VU). It prefers carbonate soils and occurs as a weed in cropped and stubble fields in traditionally farmed areas. Study of the occurrence of Stachys annua in North-Eastern Poland was conducted in 2009-2012 at four sites where the species occupied a minimum area of 30 m2 and occurred at each stage of a 4-year crop rotation (spring cereals, winter cereals, tuber crops and stubble fields). The floristically richest communities (25-34 species) were established in unploughed stubble fields, regardless of the habitat conditions. Phytocenoses with S. annua included rare species as demonstrated by high values of floristic value index (FV ranges from 25 to 36). Principle Component Analysis and Spearman rank correlations between plant traits and habitat conditions pointed to soil pH as the factor which determined S. annua phenotypic variation, in particular its height and seed production. The greatest phenotypic variation was found on the alkaline habitat, rich in nitrogen. On the other hand, the cluster analysis showed that the studied populations of inert nitrogen-poor habitats were the most similar. Electrophoretic analysis of storage proteins from S. annua seeds revealed a relatively high genetic similarity of studied populations which was reflected in the similarity coefficients — 0.76 and 0.61 by Dice and Jaccard, respectively. In the case of small or fragmented populations this poses a threat associated with inbreeding and genetic drift of S. annua, which indicates that populations of this species in the study area need to be protected from extinction.
4
Content available remote Wpływ domieszek kilku metali na właściwości krzemianu trójwapniowego
PL
W pracy przedstawiono wyniki badań wpływu dodatków ZnO, MgO, Al2O3, Cr2O3 i 2% MgO + 2% Al2O3, odpowiadający syntetycznemu alitowi. Największą wytrzymałość miał zaczyn z C3S zawierający cynk, po 28 dniach z dodatkiem 2% ZnO; wynoszącą 101 MPa. Znacznie mniejszą wytrzymałość miały próbki z dodatkiem Al2O3, a najmniejszą miał zaczyn z C3S + 1% Cr2O3. Na drugim miejscu po cynku lokuje się "syntetyczny" alit, który zapewnia dużą wytrzymałość po 1 i 2 dniach, a taką samą jak 3% dodatek ZnO po 7 dniach. Dobrą wytrzymałość daje także dodatek 2% MgO, z wyjątkiem krótkich czasów dojrzewana. Mikrokalorymetria wykazała, że występuje dobra korelacja ciepła hydratacji z wytrzymałością, aczkolwiek nie ma korelacji okresu indukcji, który jest długi w przypadku cynku, natomiast zaczyn C3S + ZnO ma po 1 dniu dużą wytrzymałość. Badania mikrostruktury zaczynów wykazały, że cynk nie jest równomiernie rozmieszczony w kryształach krzemianu trójwapniowego, są kryształy, które w ogóle nie zawierają cynku. Spowodowało to podobne zróżnicowanie w fazie C-S-H; faza ta zawierająca cynk ma nietypową morfologię.
EN
In the paper the experimental results of the influence of ZnO, MgO, Al2O3 Cr2O3 and 2% MgO + 2%Al2O3 addition to C3S, the last one corresponding to synthetic alite, on the properties of these solid solutions are presented. The highest compressive strength had the paste of C3S + ZnO, after 28 days equal to 101 MPa. Significantly lower strength had the specimens with Al2O3 and the lowest the paste of C3S+ 1% Cr2O3. On the second place after zinc was the paste of “synthetic” alite which had the high strength after 1 and 2 days and the same as the sample of C3S + 3% ZnO after 7 days. Good strength the specimens of C3S + 2% MgO are also assuring, with exception of the short period of curing. The microcalorimetry had shown the good correlation of the heat of hydration with strength, however, there was no correlation of the induction period time with early strength of the paste from C3S + ZnO. Simultaneously the observation of the pastes microstructure had shown that zinc is not uniformly distributed among the tricalcium silicate crystals; there are particles which do not contains zinc. The similar differentiation of C-S-H phase was observed; this phase containing zinc has the untypical morphology.
PL
Nanometryczną celulozę o dwóch odmianach polimorficznych (CNC I i CNC II), otrzymaną przy użyciu enzymów pochodzących od szczepu bakteryjnego Ochrobactrum anthropi, poddano modyfikacji kwasem pimelinowym. Badania szerokokątowej dyfraktometrii rentgenowskiej (WAXS) oraz spektroskopii w podczerwieni z transformacją Fouriera (FTIR) pozwoliły potwierdzić efektywność odpowiednio konwersji polimorficznej oraz modyfikacji chemicznej materiałów celulozowych. Wszystkie uzyskane napełniacze wykorzystano do wytworzenia kompozytów z chitozanem, które następnie poddano badaniom mechanicznym. Na podstawie zarejestrowanych krzywych rozciągania wyznaczono parametry cech wytrzymałościowych. Otrzymane kompozyty charakteryzowały się bardzo dobrymi właściwościami mechanicznymi. Zawartość 1% zmodyfikowanej CNC I okazała się być najefektywniejsza pod kątem zwiększania wartości modułu Younga oraz naprężenia maksymalnego przy zerwaniu. Zastosowanie modyfikacji chemicznej napełniaczy celulozowych za pomocą kwasu pimelinowego okazało się skuteczne wyłącznie dla materiałów o odmianie polimorficznej celulozy I.
EN
Nanometric celluloses of two polymorphic forms (CNC I and CNC II), obtained using the enzymes coming from Ochrobactrum anthropi bacteria, were chemically modified with pimelic acid. Wide angle X-ray scattering (WAXS) and infrared spectroscopy (FTIR) methods were used to confirm, respectively, supermolecular and chemical structures of cellulosic materials. After characterization nanometric celluloses, both modified and unmodified, were used as fillers for chitosan matrix. The obtained chitosan/nanometric cellulose composites were subjected to tensile tests. Based on the resultant tensile curves, the mechanical parameters were calculated. All the tested composites were characterized with good mechanical properties. However, in terms of Young’s modulus and tensile strength enhancement, addition of 1% of modified CNC I turned out to be optimal. Chemical modification of nanometric cellulose with pimelic acid was found to be effective only for materials with polymorphic form of cellulose I.
6
Content available Monadic Printing Revisited
EN
Expressive and clear implementation of monadic printing requires an amount of work to define and design proper abstractions to rely upon when performing the actual programming works. Our previous realization of tree printing library left us with a sense of lack with respect to these considerations. This is why we decided to re-design and re-implement the library with core algorithms based upon new, effective and expressive text printing and concatenation routines. This paper presents the results of our work.
EN
The ε→γ phase transition of HNIW induced by heat was investigated with in situ X-ray powder diffraction (PXRD). The effects of purity, particle size, insensitive additives and the time of isothermal heat treatment on the phase transition were evaluated. It was found that the phase transition is irreversible with changes in temperature, and the two phases can coexist in a certain temperature range. Moreover, the initial phase transition temperature increases with increasing purity and decreasing particle size of HNIW, and thus with the approximate crystal density. The addition of graphite and paraffin wax to HNIW as insensitive additives leads to a decrease in the initial phase transition temperature, but the addition of TATB does not affect the initial phase transition temperature. Thus, TATB is a suitable insensitive additive. Moreover, at the critical temperature, the isothermal time determined the efficiency of the ε- to γ-phase transition. This work lays the foundations for the choice of molding technologies, performance test methods, ammunition storage options, as well as the manufacture of HNIW-based explosive formulations.
EN
Isopyrum thalictroides is classified as an indicator species of the socalled ‘old-growth forests’. It occurs in shady deciduous forests and is a characteristic species of the order Fagetalia silvaticae. In many parts of Europe and Poland, it is classified in Red Lists of endangered species with different threat levels. Studies of an occurrence of I. thalictroides were carried out in the years 2000–2002 and 2010–2012 to examine changes in the abundance and morphological and genetic diversity of populations inhabiting small mid-field forest fragments (populations 2–4) and a compact forest (1 population), all located in east central Poland. Isopyrum thalictroides cover declined drastically at all isolated sites (from 83 to 93%) whereas the whole species diversity of these phytocenoses increased. By contrast, in the compact forest both, the area occupied by I. thalictroides population and the total community composition only slightly changed over time. When I. thalictroides plants sampled from all studied sites were compared in terms of the biometrical characteristics, populations 3 and 4 were found to be most similar, population 1 was less similar and population 2 was the most different of all populations, probably due to strong anthropogenic pressure. Electrophoretic analysis of seed and leaf storage proteins of Isopyrum thalictroides obtained from the four sites demonstrated that the populations were quite similar genetically, no matter how distant they were from each another. Population 2 was the most diverse, followed by population 1 whereas populations 3 and 4 were the most similar. A decreasing genetic distance in the I. thalictroides population would lead to inbreeding as seed setting by the plants will be poorer and the seeds will be less viable, which will result in a lower number of plants per a given area. The decreased gene pool indicates that the population of I. thalictroides is threatened with extinction in this area. Therefore, it is warranted to undertake some conservation measures to protect the species; hence the need arises to monitor it.
EN
Molecular modelling (MM) was used to explain the mechanism of formation of polymorphic form of isotactic polypropylene (iPP) at the surface of the silver nanoparticles (nAg). Geometrical optimization of iPP chains and unit cell of Ag systems was made with the use of MM+force field in vacuum. According to the results, the arrangement of methyl groups in the (110) contact plane implies a lateral packing of helices with a periodicity α ≈ 19 Å, which is a characteristic feature of the complicated packing of helices in β iPP. Partial charges calculated on the basis of the hybrid potential BLYP revealed the possibility of electrostatic interactions between hydrogens from methyl groups and silver atoms at the edge of unit cell. Analysis of the optimized iPP/Ag system confirmed that the formation of the polymorphic β iPP can be explained by the epitaxial mechanism.
PL
W celu wyjaśnienia mechanizmu tworzenia się formy β izotaktycznego polipropylenu (iPP) na powierzchni nanocząstek srebra (nAg) wykorzystano modelowanie molekularne (MM). Wykonano optymalizacje geometryczne układów iPP z nAg przy użyciu pola siłowego MM+ w próżni. Stwierdzono, że ustawienie grup metylowych w płaszczyźnie kontaktu (110) ujawnia boczne upakowanie helis z okresowością α ≈ 19 Å. Jest to cecha charakterystyczna dla upakowania helis w formie β iPP. Wyniki obliczeń ładunków cząstkowych przy użyciu potencjału hybrydowego BLYP wskazują na możliwość występowania oddziaływań elektrostatycznych między wodorami z grup metylowych łańcuchów iPP i atomami srebra leżącymi na krawędziach komórki elementarnej. Analiza optymalizowanych układów potwierdziła, że oddziaływanie atomów srebra z makrocząsteczką iPP może się przyczyniać do tworzenia polimorficznej formy β na drodze mechanizmu epitaksjalnego.
EN
During recent decades the number of high-pressure crystallographic studies has rapidly increased. This has been possible owing to the diamond-anvil cell, a small, relatively cheap and save apparatus breaking all records of static pressure. The diamond-anvil cell is suitable for diffraction structural studies, optical and IR spectroscopy and many other types of physical measurements; it can be also applied as a microscopic chemical reaction chamber. High pressure is now often used for synthesizing super-hard materials, new polymorphs and solvates with unique properties required in high-tech applications as well as in food processing and pharmaceutical industry.
EN
Isotactic polypropylene (iPP) nanocomposites containing 0.1, 0.2, 0.4 and 0.6 wt % of silver nanoparticles (nAg) were prepared by melt compounding in a one-screw extruder. Selected samples were isothermally recrystallized at different temperatures 50, 75, 100, 125, 130 and 135 °C, and under non-isothermal conditions. The size of the silver particles dispersed in the iPP matrix were estimated by ultraviolet/visible spectroscopy (UV-VIS). The effects of nAg additions on the structure of the iPP were studied by wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) techniques. The results clearly indicate that the addition of nAg induces the formation of the ß-iPP polymorph. It is shown that the relative amount of the b form in the recrystallized nanocomposites depends on both the concentration of silver nanoparticles and thermal conditions of recrystallization.
PL
Nanokompozyty zawierające 0,1, 0,2, 0,4 oraz 0,6 % mas. nanocząstek srebra (nAg) w matrycy izotaktycznego polipropylenu (iPP) otrzymano w procesie wytłaczania za pomocą wytłaczarki jednoślimakowej. Próbki poddano rekrystalizacji w warunkach izotermicznych, w temp. 50, 75, 100, 125, 130 i 135 °C oraz rekrystalizacji nieizotermicznej. Wymiary cząstek srebra rozproszonych w matrycy iPP określano metodą spektrometrii UV/VIS. Wpływ nanocząstek srebra na formowanie struktury nadcząsteczkowej izotaktycznego polipropylenu oceniano techniką szerokokątowej dyfrakcji promieni rentgenowskich (WAXS) oraz różnicowej kalorymetrii skaningowej (DSC). Badania wykazały, że dodane cząstki Ag przyczyniają się do powstawania formy b w matrycy iPP. Względna zawartość tej polimorficznej odmiany w matrycy iPP zależy od stężenia nanocząstek srebra w rekrystalizowanym nanokompozycie oraz warunków termicznych procesu rekrystalizacji.
EN
Bromus secalinus L. is an annual speirochoric species growing in agrocenoses of winter crops. In the past, B. secalinus L. could be found throughout Poland. The regression of the species has caused it to be classified as a rare species threatened with extinction. The study was conducted in the 2007-2010 time period, in north-eastern Poland where a considerable increase in the number of sites and abundance of B. secalinus were observed. The plant material was collected from agrocenoses of winter crops, at 14 sites representing the habitat diversity of the species occurrence. Eight morphological features were taken into account when evaluating populations of B. secalinus. The morphological diversity of the populations of B. secalinus was correlated with different habitat conditions (type, pH of soil and cultivated plant). The populations growing on the sites with optimum trophic and moisture conditions as well as those populations growing in very poor conditions were found to differ the most. A comparison of B. secalinus was done and six groups of cluster similarities were found using the agglomeration method Electrophoretic analysis of seed storage proteins of B. secalinus L from the studied populations were performed using SDS-PAGE. Analysis revealed relatively high genetic polymorphism irrespective of whether genetic variation was compared between the populations from different sites or between the subpopulations from only site number 4. Three homologenous groups were formed which were related to the cultivated plant coverage, and partially, to the type of soil. In the investigated populations and subpopulations, protein bands of molecular weight from 8 to 68 kDa were observed. The SDS-PAGE method was found suitable for the assessment of genetic variation in populations of B. secalinus L from many sites as well as within the subpopulations from one site.
EN
A rapid decrease in floristic biodiversity of agrocenoses has been observed in Europe for a half of century. A dynamic intensification of processes of crop production is considered one of the major reasons for shrinking of occurrence acreage and population number, or even extinction of numerous species with narrow ecological niche and high sensitivity to herbicides. These unfavourable transformations contribute to the gene pool restriction and necessity of species conservation. A representative of that group of plants is Illecebrum verticillatum (Caryophyllaceae) - a rare species endangered due to extinction in many European countries. Results of a study on decline of communities with Illecebrum verticillatum at the most northeastward sites in the Kałuszyn Upland (Podlasie Lowland, Eastern Poland) are presented. Observations were made on permanent plots for three periods (I - the years 1994-1997, period II - the years 2002-2004 and period III - the years 2008-2010) over the last 17 years. The material studied consisted of 136 phytosociological releves made by Braun-Blanquet method. Changes in phytocenoses with Illecebrum verticillatum were analysed and the habitat factors responsible for regression of these phytocenoses were identified. The degree of endangering of Illecebrum verticillatum in the area studied was evaluated on the basis of the frequency of occurrence, population abundance and genetic variation at the level of storage proteins in seeds by the modified SDS-PAGE method. Comparison of phytocenoses from different periods revealed a number of qualitative and quantitative differences. The number of sites of occurrence as well as population abundance of Illecebrum verticillatum have drastically decreased. Changes in the contribution of indicatory species (according to Ellenberg) were noted. In periods II and III a decrease in the contribution of hygrophilous and acidophilous species and an increase in that of nitrophilous species was observed. Significant changes in the structure of communities were confirmed by the calculated similarity indices (the most pronounced differences were observed between periods I and III). The phytocenoses were transformed towards degraded floristic composition, manifested by a decrease in the number of species in a plot, decrease in species diversity and increase in the index of domination. A significant increase in pH and nitrogen content at the habitats studied was noted. The phytocenoses reveal a replacement of nitrophilous for the eurytopic species. The factors having the strongest restricting effect on the occurrence of communities with Illecebrum verticillatum in the areas studied include: changes in the structure of agricultural use of land, increase in the contribution of maize in the structure of crops and intensification of production. At present 6 sites with Illecebrum verticillatum remain in the study area about 260 km2 (Kałuszyn Upland, Central-eastern Poland). Electrophoretic analysis of storage proteins in seeds of this species from these sites has shown high genetic similarity of these populations, irrespective of the distances between them (0-19% diversity among six the remaining populations). The diminished genetic pool of Illecebrum verticillatum population in this area indicates a need for the protection of this species.
EN
Allozyme structure of the tick population Ixodes persulcatus coded by nine enzyme gene loci has been studied using two subsamples of ticks from Irkutsk suburban areas. Nine loci out of fourteen were polymorphic in ticks of Baikal highway population, whereas five loci were polymorphic in tics sampled from Goloustnoye highway. High level of intra-population heterogeneity of ticks has been revealed. No distinction between two populations from different nidi of infection has been recorded. It was probably due to the high rate of gene migration between the studied populations and to their high genetic similarity.
16
Content available remote Large population evolutionary games played within a life history framework
EN
In many evolutionary games, such as parental care games, the length of time spent playing a realisation of the game is dependent on the strategy of an individual. Also, the payoff of a deserting male cannot be defined in isolation from the strategies used in the population as a whole. Such games should be defined as games against the field (large population games) rather than two-player games. Several examples are presented to illustrate the theory of such games against the field.
PL
W dziedzinie gier ewolucyjnych zwykle zakłada się, że każda jednostka gra wiele razy w dany rodzaj gry dwuosobowej, z tym że za każdym razem jej przeciwnik zmienia się. W przypadku gier ewolucyjnych, takich jak „wojna na wyczerpanie” czy „opieka rodzicielska”, czas wykorzystany na realizację gry zależy od strategii wybranej przez jednostkę. W takich przypadkach należy brać pod uwagę nie tylko średnią wypłatę z każdej realizacji gry, ale też średni czas potrzebny na jej realizację. W tej sytuacji model standardowej gry dwuosobowej powinien być zastąpiony grą wieloosobową. Dodatkowo, w grach typu „opieka rodzicielska” wypłata samca, który nie opiekuje się swoimi dziećmi, zależy od możliwości uzyskania dodatkowych partnerek, co z kolei zależy od strategii używanych w całej populacji. W pracy rozważono kilka przykładów gier wieloosobowych, które są wygenerowane przez grę dwuosobową.
EN
Nanometric tetragonal and monoclinic zirconia was synthesized from zirconyl chloride by the modified forced hydrolysis method. Phase transitions and morphological changes accompanying zirconia calcination in the temperaure range 600-1000 °C were studied by XRD, HR-TEM techniques and N2-porosimetry. Ageing of the amorphous hydrous zirconia at 100 °C for 48 h in the mother solution and its subsequent calcination at 600 °C for 6 h strongly favoured formation of single-phase tetragonal ZrO2 of the thermal stability enhanced by 250 °C. Influence of the calcination temperature on phase composition, grain size, grain boundaries and pore structure of the resultant ZrO2 material was analyzed.
PL
W dobie ogromnej konkurencji na generycznym rynku farmaceutycznym coraz bardziej liczy się czas, w którym firmy farmaceutyczne mogą opracować i zarejestrować odtwórczy odpowiednik leku innowacyjnego. Jedną z dróg, która pozwala zwiększyć efektywność prac na etapie rozwoju technologii wytwarzania leku oraz uniknąć wielu problemów na późniejszych etapach prac badawczych, mogą być dobrze zaprojektowane badania preformulacyjne. W publikacji zostaną przedstawione wybrane elementy badań preformulacyjnych oraz ich znaczenie dla rozwoju technologii wytwarzania stałych doustnych postaci leku generycznego.
EN
In a period of tough competition on the generic pharmaceuticals market, the time needed by pharmaceutical companies to develop and register a generic version of the reference listed drug becemes extremely important. One way to increase the effectiveness of the drug development stage and avoid a number of problems at later stages of formulation and process development may be some well designed preformulation studies. The aim of this publication is to present some of the elements of preformulation research and their importance in the development of the formulation of oral desages and generic drugs technology.
EN
N-acetylation represents one of the key pharmacogenetic traits in metabolism of xenobiotics, including drugs. Dominance of ‘slow-acetylators’ has been demonstrated in atopic patients, contact allergy and has been investigated in patients with sulfonamide hypersensitivity. The aim of this survey was to assess genotype of N-acetyltransferase2 (NAT2) polymorphism in patients with aspirin-induced urticaria (AIU). To the study we included 24 consecutive patients with medical history of urticaria induced by aspirin and 123 healthy controls. In the patients’ group oral provocation tests (OPT) up to 565mg cumulative dose of acetylsalicylic acid were performed. The NAT2 alleles (*4-wilde type, *5, *6 and *7) were determined by polymerase chain reaction-restriction fragment length polymorphism method with DNA extracted from peripherial blood. It was observed 53.7% of slow acetylators in the control group, and respectively 66.7%, 83.3% and 100% in the patients with AIU, in patients with positive OPT and in patients with positive reaction in OPT assessed as severe. Statistical significance association between NAT2*5/NAT2*6 genotype and aspirin-induced urticaria was revealed. The linkage of AIU and slow acetylation (NAT2*5/NAT2*6) seems to be highly probable in the patients with medical history of skin hypersensitivity to aspirin confirmed by positive oral provocation test.
EN
DFT calculations for two hypothetical ternary nitrides of hexavalent tungsten: LaWN3 and La2WN4 (in perovskite and K2NiF4 structures, respectively) show that these compounds should spontaneously form fromWN2 (acid) and LaN (base) reagents, or simply from (WN + 1/2 N2 orW+ N2) and LaN, at ambient or elevated temperature and high N2 pressure to speed up the reactions. This concept may be utilized to stabilize other efemeric nitrides, like these of ReVII, OsVIII, and possibly even of unprecedented IrIX. La2WN4 is example of rare two-dimensional nitride materials. Band structure calculations confirm that LaWN3, La2WN4 and several related compounds should exhibitmetallic conductivity, and they show good prospect for 2Dsuperconductivity via self-doping.
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