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971.
Materials Science - We present the results of strength and crack-growth resistance tests of Hardox-400 low-carbon highstrength steel within the temperature range from – 100 to... 相似文献
972.
Aleksandra Dębowska Agnieszka Kopia Izabela Kalemba–Rec Paweł Petrzak 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(4):427-437
The aim of the present research was to investigate the influence of different biomasses and sewage sludge ash (at 650°C for 1000 h and 2000 h, respectively) on the surface of weld cladded (Cold Metal Transfer technique, CMT) stainless steels 309 and 310. The biomass ashes were rich in K2O, CaO, SiO2, whereas sewage sludge ash in P2O5, CaO, Fe2O3, and SiO2. Characterization of the stainless steel cross-section and surface after the corrosion process inducted by the presence of ash were carried out by scanning electron microscopy (SEM) with EDAX analysis. Phase analysis of corrosion products was made by X-ray diffraction (XRD). Chromium, nickel, and iron oxides were the main oxides which occurred after the corrosion test. It has been proved that biomass ashes have the corrosive properties (because of their chemical composition) and are more aggressive than the sewage sludge ash for that kind of materials. 相似文献
973.
New analytical laboratory tools for qualitative analysis of alternative and renewable solid biofuels have been developed. The primary target of this research was to develop and then validate a rapid method for semi-quantitative and qualitative analyses of the second-generation solid biofuels. X-ray fluorescence spectroscopy (XRF) was used in combination with a two-step, multivariate modelling procedure. First, soft independent modelling of class analogies (SIMCA) and classification and regression trees (C&RT) were applied to develop and validate the classifier, which enabled different biomass origins (agrarian biomass, forest biomass and furniture waste) and different possible sources of contamination (plastic, fossil fuels and lignin-cellulose after biomass acid hydrolysis) to be distinguished. Next, the model attempted to predict the concentration of individual components using partial least-squares regression (PLSR) models. In our study, we compared C&RT and SIMCA, and the classification models (algorithms) constructed by the C&RT method were characterised as having better properties than those based on SIMCA. The C&RT classification algorithm was able to predict the origin of biomass sources with a non-error rate greater than 95%. For predictions of the addition type, the non-error rate was greater than 91%. The developed methods can rapidly and adequately determine (qualitatively) the origin of biofuels and indicate possible sources of contamination. 相似文献
974.
Sylwia Cyboran-Mikoajczyk Przemysaw Sareo Robert Pasawski Urszula Pasawska Magdalena Przybyo Kacper Nowak Micha Pciennik Halina Podbielska Marta Kopaczyska Magdalena Wawrzyska 《International journal of molecular sciences》2021,22(4)
Liposomal technologies are used in order to improve the effectiveness of current therapies or to reduce their negative side effects. However, the liposome–erythrocyte interaction during the intravenous administration of liposomal drug formulations may result in changes within the red blood cells (RBCs). In this study, it was shown that phosphatidylcholine-composed liposomal formulations of Photolon, used as a drug model, significantly influences the transmembrane potential, stiffness, as well as the shape of RBCs. These changes caused decreasing the number of stomatocytes and irregular shapes proportion within the cells exposed to liposomes. Thus, the reduction of anisocytosis was observed. Therefore, some nanodrugs in phosphatidylcholine liposomal formulation may have a beneficial effect on the survival time of erythrocytes. 相似文献
975.
Kamila Jaworecka Joanna Muda-Urban Marian Rzepko Adam Reich 《International journal of molecular sciences》2021,22(2)
Psoriasis is a chronic, systemic inflammatory disease with a genetic background that involves almost 3% of the general population worldwide. Approximately, 70–90% of patients with psoriasis suffer from pruritus, an unpleasant sensation that provokes a desire to scratch. Despite the enormous progress in understanding the mechanisms that cause psoriasis, the pathogenesis of psoriasis-related pruritus still remains unclear. In order to improve patients’ quality of life, development of more effective and safer antipruritic therapies is necessary. In turn to make it possible, better understanding of complexed and multifactorial pathogenesis of this symptom is needed. In this article we have systematized the current knowledge about pruritus origin in psoriasis. 相似文献
976.
Laboratory Full-Scale Comparative Tests of Rigid and Flexible Foundations of Buried Steel Structures
International Journal of Steel Structures - The technical issues described in the article concern the aspects of the implementation of foundations for buried flexible steel structures. The... 相似文献
977.
Ciemiorek Marta Pawliszak Łukasz Chromiński Witold Olejnik Lech Lewandowska Małgorzata 《Metallurgical and Materials Transactions A》2020,51(8):3749-3753
Metallurgical and Materials Transactions A - Electrolytic tough pitch copper rods were processed by Incremental Equal Channel Angular Pressing and subjected to short-term annealing. Conductivity of... 相似文献
978.
Dr. Justin A. Shapiro Dr. John J. Varga Dr. Derek Parsonage William Walton Prof. Dr. Matthew R. Redinbo Larry J. Ross E. Lucile White Dr. Robert Bostwick Prof. Dr. William M. Wuest Prof. Dr. Al Claiborne Prof. Dr. Joanna B. Goldberg 《ChemMedChem》2019,14(1):78-82
Antibiotics with novel mechanisms of action are desperately needed to combat the increasing rates of multidrug-resistant infections. Bacterial pantothenate kinase (PanK) has emerged as a target of interest to cut off the biosynthesis of coenzyme A. Herein we report the results of an in vitro high-throughput screen of over 10 000 small molecules against Bacillus anthracis PanK, as well as a follow-up screen of hits against PanK isolated from Pseudomonas aeruginosa and Burkholderia cenocepacia. Nine hits are structurally categorized and analyzed to set the stage for future drug development. 相似文献
979.
Paulina Kęska Joanna Stadnik Karolina Maria Wójciak Katarzyna Neffe-Skocińska 《International Journal of Food Science & Technology》2020,55(3):1069-1079
Selected physico-chemical and proteolysis-related parameters were evaluated in dry-cured loins inoculated with probiotic (Lactobacillus rhamnosus LOCK900, Bifidobacterium animalis subsp. lactis BB12) and potentially probiotic (Lactobacillus acidophilus Bauer Ł0938) lactic acid bacteria (LAB) strains and compared with a control sample at five different storage times (28, 90, 180, 270 and 360 days). Physico-chemical parameters of dry-cured loins were significantly (P < 0.01) affected by treatment, storage time and the interaction between them. The count of lactic acid bacteria (LAB) in dry-cured loins was in accordance with their pH. Higher intensity of proteolysis, as assessed by non-protein nitrogen content (NPN) and proteolysis index (PI), occurred in inoculated samples. Based on the SDS-PAGE analysis, the modifications produced during storage on the sarcoplasmic proteins were more pronounced than those exerted on the myofibrillar protein fraction. However, inoculation effect was absent from SDS-PAGE protein patterns. 相似文献
980.
ABSTRACTTi50Cu50 (at.-%) alloy has been produced from elemental Ti and Cu powders by high-energy ball milling in a planetary ball mill. Structural evolution of the alloy during milling and after subsequent heat treatment have been studied. It has been stated that high-energy ball milling of the investigated powder produces two nanocrystalline solid solutions: Cu(Ti) and Ti(Cu), both characterised by the fcc (Fm-3 m) structure. The transition of Ti structure from hcp (P63/mmc) to fcc (Fm-3 m) is observed during milling. Heat treatment of the milled powder leads to recrystallisation of Cu(Ti) and Ti(Cu) solid solutions.This paper is part of a Thematic Issue on The Crystallographic Aspects of Metallic Alloys. 相似文献