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During selection of filler materials for 3D deposition additive technologies, it is important to clarify the deformation capacity of multilayer-deposited metal in its 'as-built' structural state, which in its turn is suggested to be correlated with experimental data on ensuring or not ensuring the technological strength of corresponding products. A testing method of nickel alloys planned for applied application in 3D deposition technologies is proposed and based on conducting evaluation mechanical tests for multilayer-deposited metal, including longitudinal tensile tests (20, 1000, 1100°C), static and impact bending tests (20°C). This method is approved by testing on 14 types of wire- and powder-based filler material. Corresponding deposited metal of Hastelloy C22, Inconel 625, ЭП648, ЧC40, Inconel 718, Inconel 939, Rene 80, Inconel 738LC, ЖC6C, ЖC6C, ЖC32 nickel alloys is obtained by multilayer arc-welding deposition of 'vertical wall'-type workpieces. Two technological factors affecting deformational capacity of nickel-alloy-deposited metal in 'as-built' structural state have been exposed: the chemical composition by criteria of Al, Ti, Nb, Ta, W main alloying-elements' content, which, given their certain amount, are capable of forming γC-phase precipitate hardening; average weight content of oxygen and nitrogen. Based on the obtained experimental data on critical deformation ε, maximum bend angle before cracking β and impact strength KCU values, it is proposed to divide the nickel- alloy-deposited metal into three groups, which correlate with the possibility to provide technological strength at the current level of beam and arc 3D deposition technological development. [ABSTRACT FROM AUTHOR]

Background and Objectives : The aim of this study was to investigate the incidence of cerebrovascular pathology in patients with chronic kidney disease and its effect on functional outcomes. Materials and Methods : In a retrospective cross-sectional study (2018-2021), the medical records of patients with acute hemorrhagic and ischemic stroke with concomitant chronic kidney disease who received treatment in Riga East University Hospital Stroke Unit were analyzed. Data were analyzed using IBM SPSS 26.0. The Kruskal-Wallis, Mann-Whitney U test, and Spearman's rank correlation coefficient methods were used. Results : The final sample consisted of 305 acute cerebrovascular pathology patients (56.4% females). Overall, 57.3% of stroke patients had second-stage chronic kidney disease with average serum creatinine levels of 104.3 mmol/L (±32.8). The functional outcome of the stroke depended on the stage of chronic kidney disease. There was a statistically significant non-linear correlation between glomerular filtration rate and NIHSS (National Institute of Health Stroke Scale) score on admission (Rho -0.194, p = 0.016), glomerular filtration rate and NIHSS score on discharge (Rho -0.186, p = 0.020), and glomerular filtration rate and modified Rankin score on admission (Rho -0.237, p = 0.003) and discharge (Rho -0.224, p = 0.05). The mean NIHSS score of ischemic stroke patients was 8.3 ± 5.9 on admission and 6.5 ± 5.8 on discharge. In the hemorrhagic stroke patient group, the mean NIHSS score was 9.5 ± 7.3 on admission and 7.1 ± 6.9 on discharge. On average, 34.0% of ischemic stroke patients had an mRS score of 5 on admission, while in the hemorrhagic stroke patient group, this figure was 41%. There was no statistical difference in the glomerular filtration rate between the thrombolyzed versus non-thrombolyzed patient groups (Mann-Whitney U test = 1457, p = 0.794). Conclusions : Chronic kidney disease is an important predictor of the severity and functional outcome of a stroke; furthermore, the early management and prevention of complications should be a top priority in the prophylaxis of this cerebrovascular pathology.

This paper presents a review of the recent advances in research on the interactions between the components of lignocellulosic biomass. The literature reports on the effects of interaction between lignocellulosic biomass components, such as cellulose-lignin, lignin-hemicellulose, and hemicellulose-cellulose, were discussed. The results obtained by other researchers were analyzed from the viewpoint of the interactions between the pyrolysis products formed along with the impact effects of the organic and inorganic components present or added to the biomass with regard to the yield and composition of the pyrolysis products. Disagreements about some statements were noted along with the lack of an unequivocal opinion about the directivity of interactions occurring during biomass pyrolysis. Based on the data in the scientific literature, it was suggested that the course of the pyrolysis process of biomass blends can be appropriately directed by changes in the ratio of basic biomass components or by additions of inorganic or organic substances.

The influence of three coal tar pitches (CTPs), having softening points at 86, 94, and 103 °C, on the thermal behaviour of a defrosted high-volatile coal during co-carbonization and co-pyrolysis was studied. The following research techniques were used: X-raying of the coked charge, TG/FT-IR, ATR and UV spectroscopies, extraction, SEM, STEM, and XRD. It was determined that CTP additives change the structure of the coal plastic layer, the thickness of its zones, and the ordering degree of the structure of semi-cokes to a different extent and independently from their softening points. The softening points of CTPs do not influence the composition and yield of volatile products emitted from blends with pitch as well as the composition, structural-chemical parameters, and topological structure of material extracted from coal blends. It is suggested that such a lack of existence of any correlation between the softening points of CTPs and the degree of their influence on the thermal behaviour of coal was caused by the presence of the atoms of metals (Fe and Zn) in the CTPs. These atoms change the course of the carbonization of the CTPs themselves and their influence on organic substance of coal in blends with CTPs.

The use of chromatography in studies of coals, their progenitors and coal-related products was reviewed. The specificity of the coal structure was discussed. The use of extraction in preparing study samples was discussed paying special attention to the occurrence of undesirable phenomena such as aggregation of coal derivate molecules, resulting from the formation of their dimers and trimers, and degradation of polar solvents at temperatures above 350 °C. The following ways of fractionating samples of coal materials were considered: thermal, solvent, column with the use of preparative size exclusive chromatography and preparative thin layer chromatography as well as membrane separation. The use of chromatography coupled with experimental techniques such as mass spectrometry, infrared spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and pyrolysis was analysed.