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1.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37513896

RESUMO

The multistep synthesis of novel bis-terephthalthioamides based on methyl esters of amino acids (AAs) was proposed using conventional heating and microwave-assisted approaches. In fact, the comparative case study on the thionation of new symmetrical diamides with Lawesson's reagent (LR) was performed. The microwave-accelerated small-scale methodology was successfully employed on the whole pathway from substrates (Gly, Ala, Val, Tyr, Ser) to products (symmetrical dithioamides of terephthalic acid), resulting in significantly reduced reaction time, energy requirements, and slightly increased reaction yields when compared to conventional heating. Moreover, the intermolecular similarity of novel terephthalic acid derivatives was estimated in the multidimensional space (mDS) of the structure/property-related in silico descriptors using principal component analysis (PCA) and hierarchical clustering analysis (HCA). The distance-oriented structure/property distribution was also correlated with the experimental lipophilic data.

2.
Materials (Basel) ; 16(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37444891

RESUMO

The utilization of carbon dioxide and combustion products in cost- and energy-efficient technologies is an important element of creating sustainable energy systems, particularly in the transition period towards carbon neutrality and in light of the latest political developments, when solid fuels are still competing for a dominant role in securing energy supplies. Within the study presented, bituminous coal-derived fluidized bed fly ash samples of high calcium content, treated using a dry carbonation method under ambient conditions, were tested in terms of their specific properties to determine their usability in the preparation of injection mixtures for the filling of voids after shallow mining activities and other selected geo-engineering techniques. The study goes beyond the existing literature in terms of the carbonation method used, alkaline earth metal source, scale of the experiment, process conditions employed and product application studied. The results showed that the bituminous coal-derived fluidized bed fly ash, carbonated using the direct method adopted, may be successfully employed as the main solid component (over 82% w/w) of the injection mixtures for filling voids after shallow mining activities. The achievable compressive strength of a few MPa makes these materials applicable also in terms of ground strengthening in case it is required in light of the expected land development options to be employed. All principal materials used in the injection mixtures developed (carbonated fluidized bed fly ash, carbon dioxide, bottom ash) are industrial waste, and the carbonation method employed is simple and performed under ambient conditions, which reduces the required energy and cost input of filling mixture production, avoids the surface waste storage requirements, and contributes to the development of low energy-intensive carbon dioxide utilization and solid waste valorization methods.

3.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36835023

RESUMO

A series of seventeen 4-chlorocinnamanilides and seventeen 3,4-dichlorocinnamanilides were characterized for their antiplasmodial activity. In vitro screening on a chloroquine-sensitive strain of Plasmodium falciparum 3D7/MRA-102 highlighted that 23 compounds possessed IC50 < 30 µM. Typically, 3,4-dichlorocinnamanilides showed a broader range of activity compared to 4-chlorocinnamanilides. (2E)-N-[3,5-bis(trifluoromethyl)phenyl]-3-(3,4-dichlorophenyl)prop-2-en-amide with IC50 = 1.6 µM was the most effective agent, while the other eight most active derivatives showed IC50 in the range from 1.8 to 4.6 µM. A good correlation between the experimental logk and the estimated clogP was recorded for the whole ensemble of the lipophilicity generators. Moreover, the SAR-mediated similarity assessment of the novel (di)chlorinated N-arylcinnamamides was conducted using the collaborative (hybrid) ligand-based and structure-related protocols. In consequence, an 'averaged' selection-driven interaction pattern was produced based in namely 'pseudo-consensus' 3D pharmacophore mapping. The molecular docking approach was engaged for the most potent antiplasmodial agents in order to gain an insight into the arginase-inhibitor binding mode. The docking study revealed that (di)chlorinated aromatic (C-phenyl) rings are oriented towards the binuclear manganese cluster in the energetically favorable poses of the chloroquine and the most potent arginase inhibitors. Additionally, the water-mediated hydrogen bonds were formed via carbonyl function present in the new N-arylcinnamamides and the fluorine substituent (alone or in trifluoromethyl group) of N-phenyl ring seems to play a key role in forming the halogen bonds.


Assuntos
Antimaláricos , Antimaláricos/farmacologia , Arginase/farmacologia , Simulação de Acoplamento Molecular , Cloroquina/farmacologia , Plasmodium falciparum , Relação Estrutura-Atividade
4.
Sci Rep ; 13(1): 1190, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681710

RESUMO

The hydro-mining technology is considered as a promising method of bituminous coal excavation. The paper presents the results of the in-situ experimental campaign and modelling of hydro-cutting technology application. The proposed innovative technology was tested in terms of the effects of the distance between the outlet of water from the nozzle and a sidewall, pressure of the water jet, as well as the type of a nozzle on hydro-mining effectiveness. The hydro-cutting tests of coal seam performed in the Experimental Mine "Barbara" in Poland proved that the increase in water pressure in the range 20-40 MPa only slightly affects the coal face structure, while high pressure, of 80-100 MPa, has a significant impact on a coal face structure. The experimental results also showed the major effects of operating time as well as the distance of the water jet on the effectiveness of coal face mining.


Assuntos
Minas de Carvão , Minas de Carvão/métodos , Água , Carvão Mineral , Pressão Hidrostática , Polônia
5.
Materials (Basel) ; 15(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35744235

RESUMO

The use of waste as an energy source in cement clinker production is a promising way to transition toward a circular economy and limit carbon dioxide (CO2) in the atmosphere. The cement industry is responsible for around 5% of global CO2 emissions. In this paper, the analysis of environmental and economic profits associated with the substitution of coal by two refuse-derived fuels (RDF) and sewage sludge (SS) in a cement kiln was presented. Differences in the fuel-related CO2 emissions were calculated for two-, three-, and four-component fuel blends based on the fuel consumption data, heating values, and the correspondent emission factors. The biogenic fraction content of 19% and 43% were measured in RDFs. The material balance of fuels with the assumed technological parameters of the cement clinker production installation (capacity of 6000 Mg per day and unit heat of 3.6 GJ) shows that the RDF heat substitution at the level of 90% allows for a saving of approximately 28.6 Mg per hour of coal, and to manage even approx. 40 Mg per hour of RDF. The increase in the share of SS in the total heat consumption to 6% contributed to reducing the actual emissions by 17 kg of CO2 per 1 Mg of clinker. Multilateral benefits due to the use of RDF in the cement plant were evident.

6.
Molecules ; 27(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745019

RESUMO

Aerosol transmission constitutes one of the major transmission routes of the SARS-CoV-2 pathogen. Due to the pathogen's properties, research on its airborne transmission has some limitations. This paper focuses on silica nanoparticles (SiO2) of 40 and 200 nm sizes as the physicochemical markers of a single SARS-CoV-2 particle enabling experiments on the transmission of bioaerosols in public spaces. Mixtures of a determined silica concentration were sprayed on as an aerosol, whose particles, sedimented on dedicated matrices, were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Since it was not possible to quantitatively identify the markers based on the obtained images, the filters exposed with the AirSampler aspirator were analyzed based on inductively coupled plasma optical emission spectroscopy (ICP-OES). The ICP-OES method enabled us to determine the concentration of silica after extracting the marker from the filter, and consequently to estimate the number of markers. The developed procedure opens up the possibility of the quantitative estimation of the spread of the coronavirus, for example in studies on the aerosol transmission of the pathogen in an open environment where biological markers-surrogates included-cannot be used.


Assuntos
COVID-19 , Nanopartículas , Aerossóis/química , Humanos , Nanopartículas/química , SARS-CoV-2 , Dióxido de Silício/química
7.
Sci Rep ; 12(1): 5668, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35383252

RESUMO

The methods of fire risk assessment in its early phase employed so far used to take into account only the temperature of the heating of coal. The research works reported so far in this field have been conducted at ambient temperatures, without considering the rock mass primary temperature occurring in a particular coal seam and neglecting the depth of coal seams. The method for the determination of the composition of gases emitted from coal samples, employed in the study presented here, takes into account the effect of rock mass pressure, and therefore the depth of the coal seam, as well as the temperature typical for the rock mass in a particular coal mine. In the paper the results of the experimental research on the effects of the primary temperature of a coal seam on the content of gases emitted from coal, performed with the use of a specially designed experimental stand are presented. The method may be useful in developing fire hazard predictions for longwalls with residual coal in goafs. The relations between the self-ignition characteristics as well as selected physical properties of coal samples and carbon monoxide emission were also given. The research results proved that the accurate fire hazard assessment requires considering other than just self-heating of coal causes of carbon monoxide emission, including the rock mass primary temperature, which is expected to improve the existing methods of fire risk assessment in coal mines and post-mining areas.

8.
Materials (Basel) ; 14(19)2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34640197

RESUMO

This study presents full transient, three-dimensional numerical models of a PV-TEG hybrid module coupled with single-phase inverter by co-simulation. The influence of factors, such as wind speed, solar radiation intensity, or ambient temperature on the PV-TEG system, was also examined. The numerical model was implemented using Ansys software which accounted the phenomena of Thomson, Seebeck, and Joule's heat place on the TEG system. Furthermore, its impact on total electrical efficiency was studied. The heat transfer surface of the passive heat sink and forced air circulation positively affected the total heat transfer, and therefore helped to maintain the electrical efficiency at a higher level. Simulation of the single-phase inverter with a PV-TEG system allows the determination of the power characteristics of the system in real time. The results of the study presented may provide a basis for performance optimization of a practical PV-TEG-inverter hybrid system co-design.

9.
Sci Total Environ ; 796: 149064, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34328898

RESUMO

Carbon dioxide storage in unmineable coal seams is advantageous in the highly industrialized areas, such as the Upper Silesia Coal Basin (USCB), Poland, where heavy industry constitutes the source of huge CO2 emissions and coal mines will be closed in the future, due to unprofitability. The paper presents the results of experimental and theoretical research of CO2 capture on medium rank C and B bituminous coals coming from three mines located in the USCB. The porous texture of the investigated adsorbents was analyzed using SEM images and the N2 and CO2 isotherms at -196 °C and 0 °C, respectively. Qualitative studies using DRIFT spectroscopy showed that band intensity attributed to the functional groups of coals changed after CO2 adsorption. The analyses encompassed the equilibrium, kinetics and thermodynamics of CO2 adsorption on coals at 25, 50 and 75 °C (up to 2000 kPa). The adsorption isotherms were obtained by the static gravimetric method and described by means of the Langmuir, Freundlich, Dubinin-Radushkevich and Dubinin-Astakhov models. The highest CO2 uptakes were obtained for medium rank C bituminous coals at 25 °C; the values were 1.600 mol/kg and 1.274 mol/kg. The adsorption kinetics was better characterized by the Avrami fractional-order model rather than by the pseudo-first and pseudo-second order models. The results reveal that the adsorption process is the fastest for medium rank C bituminous coals. The isosteric heats of adsorption were calculated in the following two ways: based on the multi-temperature Toth isotherm and the Clausius-Clapeyron equations. Depending on degree of coal metamorphism, the heat of adsorption ranged from 18 to 26 kJ/mol. The estimated maximum temperature increase due to heat accumulation in the insulated coalbed during CO2 adsorption was 6 °C and did not reach the self-ignition temperature in any of the tested adsorption systems.


Assuntos
Dióxido de Carbono , Carvão Mineral , Adsorção , Estudos de Viabilidade , Cinética , Polônia , Termodinâmica
10.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201360

RESUMO

This paper presents a method of implementation and the results of aerosol dispersion tests in underground mine workings. Numerous tests were carried out to determine the potential risk of SARS-CoV-2 coronavirus infection in the underground environment of the mines. The influence of selected parameters of mine air on the possibility and method of aerosol transmission through ventilation routes was experimentally determined in real conditions. The concentration of additional aerosols in the class of ultrafine and fine aerosols increased with the distance from the generator, while the concentration of coarse particles decreased. Assuming the consumption of the solution with which aerosols were generated, even at a small level of 1 cm3/min., the number of additional aerosols was several hundred particles in one cubic centimeter of air at a distance of 50-70 m from the generator. The concentration of ultrafine particles in the range of 40-20,000 nm increased from 122 particles/cm3 to 209 particles/cm3 at air temperature of 12 °C and relative humidity of 95-96%, and from 90 particles/cm3 to 243 particles/cm3 at air temperature of 17 °C and relative humidity of 76-82%, with the increasing distance from the generator (10 m to 50 m).


Assuntos
Aerossóis/análise , COVID-19/transmissão , Minas de Carvão , Local de Trabalho/normas , Ar/análise , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Desenho de Equipamento , Humanos , Exposição Ocupacional/análise , Tamanho da Partícula , Material Particulado/análise , Polônia , SARS-CoV-2
11.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068386

RESUMO

(1) Background: Properties and descriptors are two forms of molecular in silico representations. Properties can be further divided into functional, e.g., catalyst or drug activity, and material, e.g., X-ray crystal data. Millions of real measured functional property records are available for drugs or drug candidates in online databases. In contrast, there is not a single database that registers a real conversion, TON or TOF data for catalysts. All of the data are molecular descriptors or material properties, which are mainly of a calculation origin. (2) Results: Here, we explain the reason for this. We reviewed the data handling and sharing problems in the design and discovery of catalyst candidates particularly, material informatics and catalyst design, structural coding, data collection and validation, infrastructure for catalyst design and the online databases for catalyst design. (3) Conclusions: Material design requires a property prediction step. This can only be achieved based on the registered real property measurement. In reality, in catalyst design and discovery, we can observe either a severe functional property deficit or even property famine.


Assuntos
Desenho de Fármacos , Nanotecnologia , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Catálise , Bases de Dados Factuais , Teste de Materiais
12.
Int J Mol Sci ; 22(7)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810550

RESUMO

A library of novel 4-{[(benzyloxy)carbonyl]amino}-2-hydroxybenzoic acid amides was designed and synthesized in order to provide potential acetyl- and butyrylcholinesterase (AChE/BChE) inhibitors; the in vitro inhibitory profile and selectivity index were specified. Benzyl (3-hydroxy-4-{[2-(trifluoromethoxy)phenyl]carbamoyl}phenyl)carbamate was the best AChE inhibitor with the inhibitory concentration of IC50 = 36.05 µM in the series, while benzyl {3-hydroxy-4-[(2-methoxyphenyl)carbamoyl]phenyl}-carbamate was the most potent BChE inhibitor (IC50 = 22.23 µM) with the highest selectivity for BChE (SI = 2.26). The cytotoxic effect was evaluated in vitro for promising AChE/BChE inhibitors. The newly synthesized adducts were subjected to the quantitative shape comparison with the generation of an averaged pharmacophore pattern. Noticeably, three pairs of fairly similar fluorine/bromine-containing compounds can potentially form the activity cliff that is manifested formally by high structure-activity landscape index (SALI) numerical values. The molecular docking study was conducted for the most potent AChE/BChE inhibitors, indicating that the hydrophobic interactions were overwhelmingly generated with Gln119, Asp70, Pro285, Thr120, and Trp82 aminoacid residues, while the hydrogen bond (HB)-donor ones were dominated with Thr120. π-stacking interactions were specified with the Trp82 aminoacid residue of chain A as well. Finally, the stability of chosen liganded enzymatic systems was assessed using the molecular dynamic simulations. An attempt was made to explain the noted differences of the selectivity index for the most potent molecules, especially those bearing unsubstituted and fluorinated methoxy group.


Assuntos
Acetilcolinesterase/química , Butirilcolinesterase/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/síntese química , Simulação de Acoplamento Molecular , Acetilcolinesterase/metabolismo , Ácido Aminossalicílico/química , Butirilcolinesterase/metabolismo , Carbamatos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Análise por Conglomerados , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Análise de Componente Principal , Solventes , Relação Estrutura-Atividade , Células THP-1
13.
Sensors (Basel) ; 21(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924981

RESUMO

Modern dentistry commonly uses a variety of imaging methods to support diagnosis and treatment. Among them, cone beam computed tomography (CBCT) is particularly useful in presenting head structures, such as the temporomandibular joint (TMJ). The determination of the morphology of the joint is an important part of the diagnosis as well as the monitoring of the treatment results. It can be accomplished by measurement of the TMJ gap width at three selected places, taken at a specific cross-section. This study presents a new approach to these measurements. First, the CBCT images are denoised using curvilinear methods, and the volume of interest is determined. Then, the orientation of the vertical cross-section plane is computed based on segmented axial sections of the TMJ head. Finally, the cross-section plane is used to determine the standardized locations, at which the width of the gap between condyle and fossa is measured. The elaborated method was tested on selected TMJ CBCT scans with satisfactory results. The proposed solution lays the basis for the development of an autonomous method of TMJ index identification.


Assuntos
Côndilo Mandibular , Transtornos da Articulação Temporomandibular , Tomografia Computadorizada de Feixe Cônico , Humanos , Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem
14.
Sci Rep ; 11(1): 8851, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893382

RESUMO

The aim of the paper was to work out a new comprehensive methodology to monitor thermal activity at mine waste dumps. The methodology was tested through monitoring thermal phenomena occurring in the areas of extractive waste dumping facilities located in the Upper Silesian Coal Basin, Poland. Within the framework of the study, a comparative analysis of three waste dumps was performed; the first two of them, which were not previously reclaimed, are in part thermally active, whereas the third one comprises one section which was partially reclaimed and another section which is still being operated. The research objective was to observe the changes of atmospheric emissions of Polycyclic Aromatic Hydrocarbons (PAHs) from the three selected facilities within the period of 21 months of constant monitoring. The novelty of the methodology of thermal activity monitoring at burning mine waste dumps consisted in the application advanced chemometrics methods. The collected data were analyzed by means of the Hierarchical Clustering Analysis supplemented with a color map of the experimental results. Based on the newly developed methodology, it was determined that thermal processes occur in all of the three analyzed sites. The non-reclaimed waste dumps characterize of intense thermal phenomena covering the majority of the studied area. It was also observed that the most intensive thermal activity occurs in the central sections of the dumps with temperature values reaching the level of 600 °C accompanied by high emissions of PAHs. In addition, the research results demonstrate that despite the reclamation processes, there are certain areas which still remain thermally active in one of the studied extractive waste dumps. This manifested itself by high measured concentrations of all the analyzed PAHs and locally increased surface temperatures which, however, did not exceed 200 °C; the majority of the areas of the reclaimed waste dump characterized of temperatures in the range of 20-30 °C.

15.
Environ Pollut ; 276: 116766, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33631690

RESUMO

Air pollution constitutes the greatest environmental threat to human health in the European Union. In Poland, the emission of particulate matter and harmful gases originating from local coal based boiler plants and the combustion of fuels in residential heating appliances is a considerable source of air pollution. The combustion of fuel in home furnaces is inefficient due to the use of cheap fuels of low heating parameters and the frequent addition of waste. For the purpose of the research, deciduous tree wood pellets were selected as the basic fuel with the admixture of plastic waste, rubber, waste paper, wood residues, diapers, textile waste, multi-material packaging, construction waste, biomass and alternative fuel (RDF). Examining ash samples to confirm the practices of combusting or co-combusting waste materials in heating appliances is considered to be one of the most reliable detection methods; however, the results of direct research require further data processing. The application of hierarchical clustering analysis to the obtained results arranged into a matrix enabled in a simple way to demonstrate the similarities between the examined samples of fuel and the samples of fuel mixed with waste materials in the parameters space as well as to analyze the similarities among the measured parameters (the content of particular elements in ash) in the space of the examined samples. The application of chemometric methods for the purpose of identifying the combusted fuels, and, in particular the co-combusted waste complements the currently used monitoring tools which control the use of low quality fuels or the combustion of waste of different origin.


Assuntos
Poluentes Atmosféricos , Madeira , Poluentes Atmosféricos/análise , Análise por Conglomerados , Carvão Mineral/análise , Humanos , Material Particulado/análise , Polônia , Madeira/química
16.
Materials (Basel) ; 14(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419195

RESUMO

The aim of the paper is to present the results of research on the carbonation process kinetics of coal combustion ashes originating from fluidized bed boilers used in power plants. Based on the thermogravimetric analysis (TGA), the hypothesis that carbon dioxide is bounded by the mineral substances (calcium compounds) in the fly ashes was confirmed. Determining the kinetic parameters of the carbonation of fly ashes requires simultaneously taking into consideration the kinetics of the drying process of the sample. The drying process of the sample masks the effect of the reaction of CO2 with calcium compound. Unlike the ashes generated in pulverized fuel boilers, fly ashes contain irregular amorphic mineral components or poorly crystalized products of complete or partial dehydroxylation of claystone substance present in shale formations constituting the gangue as well as anhydrite (CaSO4), a desulfurization product. The content of free calcium oxide (CaO) in such ashes ranges from a few to several percent, which is a significant obstacle considering their use in cement and concrete production as type II admixtures understood to be inorganic grained materials of pozzolanic or latent hydraulic properties. The paper presents effective mechanisms which reduce the content of free CaO in ashes from Fluidized Bed Combustion (FBC) boilers to a level that allows their commercial utilization in the cement industry.

17.
Int J Phytoremediation ; 23(4): 415-425, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32976720

RESUMO

Alders, as an N-fixing species, are widely used as a phytomelioration species at post-industrial sites. The paper presents the effects of litter decomposition of different alder species-black alder, gray alder, and green alder-on changes to the soil solution chemistry of Technosols developed from two types of substrates: lignite combustion waste and sandy substrates from a former sand quarry. Under controlled conditions, the 13-week experiment investigated pH, electrical conductivity (EC), and the chemical parameters-dissolved organic carbon (DOC), dissolved nitrogen (DON), and macroelements S, Ca, Mg, K, and Na content-of filtrates in composites consisting of substrate and litter from alder species was investigated. Alder litter accelerated nutrient leaching processes from soil substrates and had the greatest impact on sandy substrates because fast leaching was possible at low absorption capacity characteristics. Higher leaching rates in sandy substrates were also observed, especially in the cases of DOC, DON, K, and P, in comparison to combustion waste substrates. In the first phase of the experiment in sandy soil substrates, the dominant process is the leaching of DOC from dead organic matter, while in the case of combustion waste, calcium leaching prevails in the first phase. Among the investigated species, black alder had the greatest impact on the chemistry of substrates and solutions, and the dynamic of these processes has a different path at various substrates.


Assuntos
Alnus , Biodegradação Ambiental , Carbono , Carvão Mineral , Laboratórios , Areia , Solo
18.
Materials (Basel) ; 13(21)2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33147783

RESUMO

The research was carried out by means of implosion plasma generators with conical and hemispherical compression chambers to conduct a quantitative assessment of the boundary temperature of super dense plasma jets. It was proved experimentally that nuclear transformations in metals are caused by the impact of super dense plasma jets (11, ..., 12) × 103 kg/m3. The boundary temperature of these jets was evaluated. It was estimated that the nominal boundary temperature of the studied implosion plasma generators is 106 К. The pressure in the target at the penetration of the super dense jet (~12,000 kg/m3) at the speed of 28,000 m / sec is more than 30 ТPa. The boundary temperature was estimated and proved to depend on the pre-determined values only slightly. It was experimentally established that stable isotopes of manganese Mn55 (up to 27%) are formed in iron targets as a result of high temperature plasma jet penetration. The appearance of manganese must be related to iron transformation into stable isotopes Fe56 and Fe54. The obtained results may be applied for investigating structural changes in metals under the conditions of impulsive super high temperatures and pressures. This method can be also used as a testing ground for studying the physical conditions of forming chemical elements as well as super dense plasma jets.

19.
Int J Mol Sci ; 21(18)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916824

RESUMO

A series of twenty-two novel N-(disubstituted-phenyl)-3-hydroxynaphthalene- 2-carboxamide derivatives was synthesized and characterized as potential antimicrobial agents. N-[3,5-bis(trifluoromethyl)phenyl]- and N-[2-chloro-5-(trifluoromethyl)phenyl]-3-hydroxy- naphthalene-2-carboxamide showed submicromolar (MICs 0.16-0.68 µM) activity against methicillin-resistant Staphylococcus aureus isolates. N-[3,5-bis(trifluoromethyl)phenyl]- and N-[4-bromo-3-(trifluoromethyl)phenyl]-3-hydroxynaphthalene-2-carboxamide revealed activity against M. tuberculosis (both MICs 10 µM) comparable with that of rifampicin. Synergistic activity was observed for the combinations of ciprofloxacin with N-[4-bromo-3-(trifluoromethyl)phenyl]- and N-(4-bromo-3-fluorophenyl)-3-hydroxynaphthalene-2-carboxamides against MRSA SA 630 isolate. The similarity-related property space assessment for the congeneric series of structurally related carboxamide derivatives was performed using the principal component analysis. Interestingly, different distribution of mono-halogenated carboxamide derivatives with the -CF3 substituent is accompanied by the increased activity profile. A symmetric matrix of Tanimoto coefficients indicated the structural dissimilarities of dichloro- and dimetoxy-substituted isomers from the remaining ones. Moreover, the quantitative sampling of similarity-related activity landscape provided a subtle picture of favorable and disallowed structural modifications that are valid for determining activity cliffs. Finally, the advanced method of neural network quantitative SAR was engaged to illustrate the key 3D steric/electronic/lipophilic features of the ligand-site composition by the systematic probing of the functional group.


Assuntos
Anti-Infecciosos/síntese química , Staphylococcus aureus Resistente à Meticilina , Mycobacterium tuberculosis , Naftalenos/química , Testes de Sensibilidade Microbiana
20.
Molecules ; 25(18)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916979

RESUMO

A series of nineteen novel ring-substituted N-arylcinnamanilides was synthesized and characterized. All investigated compounds were tested against Staphylococcus aureus as the reference strain, two clinical isolates of methicillin-resistant S. aureus (MRSA), and Mycobacterium tuberculosis. (2E)-N-[3-Fluoro-4-(trifluoromethyl)phenyl]-3-phenylprop-2-enamide showed even better activity (minimum inhibitory concentration (MIC) 25.9 and 12.9 µM) against MRSA isolates than the commonly used ampicillin (MIC 45.8 µM). The screening of the cell viability was performed using THP1-Blue™ NF-κB cells and, except for (2E)-N-(4-bromo-3-chlorophenyl)-3-phenylprop-2-enamide (IC50 6.5 µM), none of the discussed compounds showed any significant cytotoxic effect up to 20 µM. Moreover, all compounds were tested for their anti-inflammatory potential; several compounds attenuated the lipopolysaccharide-induced NF-κB activation and were more potent than the parental cinnamic acid. The lipophilicity values were specified experimentally as well. In addition, in silico approximation of the lipophilicity values was performed employing a set of free/commercial clogP estimators, corrected afterwards by the corresponding pKa calculated at physiological pH and subsequently cross-compared with the experimental parameters. The similarity-driven property space evaluation of structural analogs was carried out using the principal component analysis, Tanimoto metrics, and Kohonen mapping.


Assuntos
Cinamatos/síntese química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Ampicilina/farmacologia , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Inflamação , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Micro-Ondas , Modelos Moleculares , NF-kappa B/metabolismo , Análise de Componente Principal , Relação Estrutura-Atividade , Células THP-1
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