Исследование золы Северской ТЭЦ как наполнителя в серные композиционные материалы

Получен серный композиционный материал при сплавлении золы с серой. Результаты определения прочности показали, что полученный серный композиционный материал имеет марку М200 и может использоваться для бетонов общестроительных марок. Рассмотрены модифицирующие добавки, стабилизирующие структуру серного вяжущего. Изучено влияние Na2SiO3, ZnCl2 и AlCl3 на прочность и водостойкость серного композиционного материала. Данная работа актуальна и находит практический интерес в строительной индустрии.The sulfur composite material is obtained by fusing the ash with sulfur. The results of the determination of strength showed that the sulfur composite material has the M200 grade and can be used for concrete of construction marks. Modifying additives that stabilize the structure of sulfur binder are considered. The influence of Na2SiO3, ZnCl2 and AlCl3 on the strength and water resistance of sulfur composite material was studied. This work is relevant and is of practical interest in the construction industry

Synergetic Antimicrobial Activity and Mechanism of Clotrimazole-Linked CO-Releasing Molecules

This work was financially supported by Fundação para a Ciência e Tecnologia (Portugal) through fellowship PD/BD/ 148006/2019 (SSM), PTDC/SAU-INF/29313/2017 grant, and R&D unit LISBOA-01-0145-FEDER007660 (MostMicro) cofounded by FCT/MCTES and FEDER funds under the PT2020 Partnership Agreement. The NMR data was acquired at CERMAX, Instituto de Tecnologia Quıḿ ica e Bioloǵ ica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal, with equipment funded by FCT, project AAC 01/ SAICT/2016. This work was partially supported by the PPBIPortuguese Platform of BioImaging (PPBI-POCI-01- 0145-FEDER-022122) cofunded by national funds from OE “Orçamento de Estado” and by European funds from FEDER“Fundo Europeu de Desenvolvimento Regional”. LMS and SSM acknowledge funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 810856. H.B.-O., T.S., C.M., F.O., J.B., and M.A. gratefully acknowledge funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), project ID 398967434 (TRR 261, projects A01, A06, A10, and Z02). A.B. appreciates funding by the German Federal Ministry for Education and Research (project Gramneg. Design).Several metal-based carbon monoxide-releasing molecules (CORMs) are active CO donors with established antibacterial activity. Among them, CORM conjugates with azole antibiotics of type [Mn(CO)3(2,2′-bipyridyl)(azole)]+ display important synergies against several microbes. We carried out a structure-activity relationship study based upon the lead structure of [Mn(CO)3(Bpy)(Ctz)]+ by producing clotrimazole (Ctz) conjugates with varying metal and ligands. We concluded that the nature of the bidentate ligand strongly influences the bactericidal activity, with the substitution of bipyridyl by small bicyclic ligands leading to highly active clotrimazole conjugates. On the contrary, the metal did not influence the activity. We found that conjugate [Re(CO)3(Bpy)(Ctz)]+ is more than the sum of its parts: while precursor [Re(CO)3(Bpy)Br] has no antibacterial activity and clotrimazole shows only moderate minimal inhibitory concentrations, the potency of [Re(CO)3(Bpy)(Ctz)]+ is one order of magnitude higher than that of clotrimazole, and the spectrum of bacterial target species includes Gram-positive and Gram-negative bacteria. The addition of [Re(CO)3(Bpy)(Ctz)]+ to Staphylococcus aureus causes a general impact on the membrane topology, has inhibitory effects on peptidoglycan biosynthesis, and affects energy functions. The mechanism of action of this kind of CORM conjugates involves a sequence of events initiated by membrane insertion, followed by membrane disorganization, inhibition of peptidoglycan synthesis, CO release, and break down of the membrane potential. These results suggest that conjugation of CORMs to known antibiotics may produce useful structures with synergistic effects that increase the conjugate's activity relative to that of the antibiotic alone.publishersversionpublishe

Assessment of Myocardial Edema by Computed Tomography in Myocardial Infarction

ObjectivesThe aim of this study was to analyze whether cardiac computed tomography (CT) permits the assessment of myocardial edema in acute myocardial infarction (MI).BackgroundSeveral studies proved the value of detecting myocardial edema from T2-weighted cardiac magnetic resonance (CMR) for differentiating acute from chronic MI. Computed tomography is suited for depicting MI, but there are no data on CT imaging of myocardial edema. We hypothesized that areas of reduced attenuation in acute MI may correspond to edema.MethodsIn 7 pigs (55.2 ± 7.3 kg), acute MI was induced using a closed chest model. Animals underwent unenhanced arterial and late-phase dual source computed tomography (DSCT) followed by T2-weighted and delayed contrast-enhanced CMR. Animals were sacrificed, and the excised hearts were stained with 2,3,5-triphenyltetrazolin chloride (TTC). Size of MI, contrast-to-noise ratio, and percent signal difference were compared among the different imaging techniques with concordance-correlation coefficients (ρc), Bland-Altman plots, and analysis of variance for repeated measures.ResultsInfarction was transmural on all slices. On unenhanced, arterial, and late-phase DSCT, mean sizes of MI were 27.2 ± 8.5%, 20.1 ± 6.9%, and 23.1 ± 8.2%, respectively. Corresponding values on T2-weighted and delayed enhanced CMR were 28.5 ± 7.8% and 22.2 ± 7.7%. Size of MI on TTC staining was 22.6 ± 7.8%. Best agreement was observed when comparing late-phase CT (ρc = 0.9356) and delayed enhanced CMR (ρc = 0.9248) with TTC staining. There was substantial agreement between unenhanced DSCT and T2-weighted CMR (ρc = 0.8629). Unenhanced DSCT presented with the lowest percent signal difference (46.0 ± 18.3) and the lowest contrast-to-noise ratio (4.7 ± 2.0) between infarcted and healthy myocardium.ConclusionsUnenhanced DSCT permits the detection of myocardial edema in large acute MI. Further studies including smaller MI in different coronary artery territories and techniques for improving the contrast-to-noise ratio are needed