605 research outputs found
Selections and their Absolutely Continuous Invariant Measures
Let and consider disjoint closed regions in and subintervals such that projects
onto We define the lower and upper maps by the
lower and upper boundaries of respectively. We assume
, to be piecewise monotonic and preserving continuous
invariant measures and , respectively. Let and
be the distribution functions of and The main
results shows that for any convex combination of and
we can find a map with values between the graphs of and
(that is, a selection) such that is the -invariant
distribution function. Examples are presented. We also study the relationship
of the dynamics of multi-valued maps to random maps
Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5
Highly siliceous zeolites, namely MFI type have attracted the great attention due to their higher hydrothermal stability, higher selectivity to organic compounds, and often better catalytic properties in comparison with Al-rich zeolites. The native zeolite (Si/Al = 164) and its desilicated analogues were deeply characterized with regard to their structural and textural properties by X-ray diffraction, low temperature adsorption of nitrogen and solid-state Al-27 MAS NMR. Their acidic properties were evaluated in quantitative IR studies. Finally, the catalytic performance of desilicated zeolites ZSM-5 was evaluated in the cracking of n-decane, 1,3,5-tri-iso-propylbenzene and vacuum gas oil. In this article, it is shown that high silica zeolites prepared by NaOH and NaOH&TBAOH leaching presented good hydrothermal stability with only slightly lower resistance when comparing to native steamed zeolite. The mesoporosity was preserved after the steaming treatment. The influence of the generated mesoporosity on the higher activity was evidenced in both 1,3,5-tri-isopropylbenzene and diesel oil cracking of steamed hierarchical zeolites. In spite of their lowered acidity, the mesopores system benefited the diffusion of the bulky molecule and finally provided higher activity of hierarchical zeolites. (C) 2016 Elsevier Inc. All rights reserved.This work was financed by Grant No. 2015/18/E/ST4/00191 from the National Science Centre - Poland. F. Rey and J. Martinez-Triguero thank for the support of the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), MAT2015-71842-P and CTQ2015-68951-C3-1-R.Tarach, KA.; Martínez-Triguero, J.; Rey Garcia, F.; Góra-Marek, K. (2016). Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5. Journal of Catalysis. 339:256-259. https://doi.org/10.1016/j.jcat.2016.04.023S25625933
Mutagenicity induced in Salmonella strains TA98 and TA100 by diphenylthiophenes
Mutagenic properties of four different diphenylthiophenes: 3,4-diphenylthiophene, 3,4-di(4'-methylphenyl)thiophene, 3,4-di(4'-methoxyphenyl)thiophene and 3,4-di(4'-pentoxyphenyl)thiophene were investigated applying the Salmonella test. The research was done on two strains of Salmonella Typhimurium: TA98 and TA100, tested in two variants: with (+S9) and without (-S9) enzymatic activation. Only one compound 3,4-di(4'-methylphenyl)thiophene showed mutagenic activity when studied with metabolic activation (+S9) and its mutagenic rate (MR) score was 3.41 for the dose of 10.00µg*plate-1. Other studied compounds did not show any mutagenic activity (+/-S9) and their MR score did not exceed the threshold value of 2.0
2,4-diphenylthiophene induces mainly base pair mutation in Salmonella Typhimurium
Heterocyclic aromatic compounds containing sulfur (S-HET), have been detected in air, soil, marine environment and freshwater sediment. Toxicity and mutagenicity data of this class of substances are scarce. The present study focuses on implications of two aryl thiophenes and their mutagenic properties in Salmonella/microsome test. In our experiment only 2,4-diphenylthiophene showed little mutagenic effect in both variants of activaction (+/-S9) in strain TA100. Thiophene ring joined to K-region of phenanthrene did not change the biological activity of 3,6-dimetoxyphenanthro [9,10-c]thiophene and this compound did not show mutagenic potency
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Energy Performance Analysis of A PV/T System Coupled with Domestic Hot Water System
Abstract: In this paper, a standalone photovoltaics‐thermal solar panel is modelled using the TRNSYS simulation engine. Based on this, it is explored how such a system can be comprised with thermal and electrical storage components to provide electricity and hot water for a dwelling in a warm location in Europe. Furthermore, it is investigated how by cooling the temperature of the solar cells, the electrical power output and efficiency of the panel is improved. The performance of the system has also been studied and it is investigated by what amount the solar panel is able to convert the solar energy into electricity. Through this, it is discovered that when the temperature of the panel is reduced on average by 20%, the electrical power output is increased by nearly 12%. Moreover, it is demonstrated that the modelled system can provide hot water under different solar radiation conditions and during all seasons of the year. UK Department of Energy and Climate Change (DECC); Innovation and Networks Executive Agency (INEA), European Commissio
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Life cycle assessment of plastic waste and energy recovery
Data availability:
Data will be made available on request.Copyright © 2023 The Authors. Plastics are essential in our economy and everyday life. However, plastic pollution is a global concern. To address this issue, the European Strategy for Plastics in a Circular Economy was adopted in January 2018. Attention has been raised to the entire life cycle of products, with legislation stating that plastic used throughout the design phase to manufacturing and packaging phases needs to be recyclable by 2030. This study evaluates selected plastic material categories and technologies carrying out a review of Life Cycle Assessment (LCA) analysis from literature. The literature review was carried out, the indicator units for impact categories among the investigated mid-point methodologies as well as the conversion factors for the metrics harmonization were provided and finally a detailed analysis of the environmental impact of several types of plastics was carried out for two options in the waste hierarchy, which are through disposal by sending waste to landfills and incineration with energy recovery. The disposal, treatment and recycling of 2.2 tonnes of general plastic waste including non-recyclable material delivered to a recycling facility was considered for comparison with these methods. An assessment of the comparative advantages of each practice was conducted. The potential for energy recovery was highlighted.European Union's H2020 programme ETEKINA and iWAYS under grant agreement numbers 768772 and 958274, respectively
Hierarchical zeolites TNU-9 and IM-5 as the catalysts for cracking processes
[EN] The 10-ring zeolites TNU-9 and IM-5 were obtained by a desilication and evaluated in series of acid-catalysed cracking reactions. n-Decane and 1,3,5-tri-iso-propylbenzene cracking were performed as model reactions, while vacuum gas oil, polypropylene and polyethylene were cracked into add-value lower molecular weight chemicals. The catalytic performance improvement of hierarchical zeolites was rationalized by deep acid sites characterization in situ FT-IR studies of pyridine, carbon monoxide and 2,6-di-tert-butylpyridine sorption. Further, operando FT-IR-GC studies supported by 2D COS (two-dimensional correlation) analysis provided insight into cracking and coking of catalysts during polypropylene and polyethylene decomposition. It was found that NaOH-derived catalysts ensure the most upsurged acidity, in terms of number and accessibility of the sites, and then with better performance. In VGO cracking the connected mesopores added post-synthesis increased yields to propylene and middle distillates and lowered coke production. A bigger share of iso-olefins was observed both in VGO and polyolefins cracking products.KGM acknowledges the Grant No 2021/43/B/ST4/00307 form National Science Center, Poland. KAT acknowledges the Grant No 2020/37/B/ST4/01215 form National Science Center, Poland. For the purpose of Open Access, the author has applied a CC-BY public copyright licence to any Author Accepted Manuscript (AAM) version arising from this submission. JMT acknowledges the Grant MFA/2022/016 from Advanced Materials program supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17. I1) and by Generalitat Valenciana. The study was carried out using research infrastructure purchased with the funds of the European Union in the framework of the Smart Growth Operational Program, Measure 4.2; Grant No. POIR.04.02.00-00-D001/20-00, "ATOMIN 2.0-ATOMic scale science for the INnovative economy". The open-access publication of this article has been supported by a grant from the Faculty of Chemistry under the Strategic Programme Excellence Initiative at Jagiellonian University.Tarach, KA.; Martínez-Triguero, J.; Valencia Valencia, S.; Wojciechowska, K.; Rey Garcia, F.; Góra-Marek, K. (2023). Hierarchical zeolites TNU-9 and IM-5 as the catalysts for cracking processes. Applied Catalysis B Environmental. 338. https://doi.org/10.1016/j.apcatb.2023.12306633
Digital expansions with negative real bases
Similarly to Parry's characterization of -expansions of real numbers
in real bases , Ito and Sadahiro characterized digital expansions in
negative bases, by the expansions of the endpoints of the fundamental interval.
Parry also described the possible expansions of 1 in base . In the
same vein, we characterize the sequences that occur as -expansion of
for some . These sequences also describe
the itineraries of 1 by linear mod one transformations with negative slope
Investigations on improvement of functionality of silicone ectoprostheses
Silikonowe protezy twarzy (epitezy, ektoprotezy, protezy zewnętrzne) stosowane są u pacjentów, którzy w wyniku zabiegu chirurgicznego, w ramach leczenia chorób nowotworowych, wad wrodzonych, urazu utracili tkanki miękkie i twarde w zakresie twarzoczaszki np. oko, ucho, nos. Rekonstrukcje protetyczne wykorzystuje się w przypadku, gdy metody chirurgii plastycznej są nieskuteczne lub nie mogą być zastosowane. Istnieją różne metody umocowania ektoprotez. Badania kliniczne i ankietowe wykazały, iż większość pacjentów w pierwszej kolejności wybierała kleje medyczne. Niestety kleje te charakteryzują się krótkim czasem trwałego przytwierdzenia protezy do miejsca ubytku. W pracy zbadano przyczepności trzech rodzajów materiałów silikonowych przytwierdzanych do skóry pacjentów za pomocą klejów i taśm komercyjnych. W celu poprawy adhezji tworzywa zastosowano dwa rodzaje modyfikacji powierzchni. Zbadano wpływ obróbki mechanicznej na powierzchnie silikonów (gwarantujący wzrost chropowatości powierzchni). Zbadano także skuteczność chemicznej metody obróbki powierzchni (trawienie tworzywa w roztworach kwasów nieorganicznych). Celem weryfikacji skuteczności zastosowanych metod modyfikujących powierzchnię opracowano metodę pomiaru adhezji pomiędzy materiałem polimerowym a badanym środkiem klejącym (taśma, klej) wykorzystując w tym celu układ uchwytów uniwersalnej maszyny wytrzymałościowej.Silicone facial prostheses (epitheses, ecto-prostheses, external prostheses) are applied for patients who lost soft and hard tissues in craniofacial area, e. g. eye, ear, nose, due to a surgical treatment; tumour diseases treatment; birth defects or injuries. Prosthetic reconstructions are used when plastic surgery methods are ineffective, or cannot be applied. There are various methods of the ecto-prostheses fastening. Clinical tests and surveys revealed that the first choice for the majority of patients is medical glues. However, such glues can provide only short-time fastening of prosthesis to the damaged area. The work presents results of investigations on adhesion of three kinds of silicone materials fastened to patients' skin with the use of commercial glues and adhesive tapes. In order to improve the materials' adhesion two methods of their surface modification were applied. Influence of a mechanical treatment on the materials' surface was investigated. Effectiveness of the surface chemical treatment i.e. etching of the materials with inorganic acids solutions was investigated. In order to verify effectiveness of the applied surface modification methods a testing method of adhesion between the material and the adhesive agent i.e. adhesive tape or glue was developed. The testing method utilised a universal testing machine
Ce-modified zeolite BEA catalysts for the trichloroethylene oxidation. The role of the different and necessary active sites
[EN] This paper reports the activity of different Ce-BEA zeolites for the catalytic oxidation of trichloroethylene and it is focused on determining the nature of the catalyst active sites. The study was made by using a microporous zeolite BEA, two types of desilicated BEA zeolites and mildly steamed desilicated BEA zeolites. The catalysts were prepared by introducing Ce to the zeolites with incipient wetness impregnation and their structural, textural, and acidic properties were established. The evolution of TCE conversion was correlated with the physicochemical properties of the zeolites. It is shown that highly developed mesopore surface area, well-dispersed cerium species and a high number of Bronsted sites results in the highest activity. The activity and selectivity of the Ce-loaded zeolites were found to be dependent on the number of high strength Bronsted acid centres. The hierarchical materials with a higher density of hydroxyls showed higher yields to HCl while the formation of chlorine was prevented.The work was financed by the Grant No. 2015/18/E/ST4/00191 from the National Science Centre, Poland. J.M-T. and A.E.P thank Spanish Governmentthrough "Severo Ochoa" SEV-2016-0683, RTI2018-099668-B-C21, RTI2018-101784-B-I00 and the Fundacion Ramon Arecesthrough a research contract of the "Life and Materials Science" program.Golabek, K.; Palomares Gimeno, AE.; Martínez-Triguero, J.; Tarach, KA.; Kruczala, K.; Girman, V.; Góra-Marek, K. (2019). Ce-modified zeolite BEA catalysts for the trichloroethylene oxidation. The role of the different and necessary active sites. Applied Catalysis B Environmental. 259:1-12. https://doi.org/10.1016/j.apcatb.2019.11802211225
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