Autor: Walczak, Tadeusz. - Katalog OPAC zbiorów

Tytuł:: Factors Influencing Cavitation Erosion of NiCrSiB Hardfacings Deposited by Oxy-Acetylene Powder Welding on Grey Cast Iron
Autorzy:: Szala, Mirosław
Walczak, Mariusz
Hejwowski, Tadeusz
Powiązania:: https://bibliotekanauki.pl/articles/2023792.pdf
Data publikacji:: 2021
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: hardness
stainless steel
cavitation erosion
cast iron
surface engineering
powder welding
surface roughness
hardfacing
twardość
stal nierdzewna
erozja kawitacyjna
żeliwo
inżynieria powierzchni
spawanie proszkowe
chropowatość powierzchni
utwardzanie
Opis:: The work presents the results of a study on cavitation erosion (CE) resistance of two NiCrSiB self-fluxing powders deposited by oxy-acetylene powder welding on cast iron substrate grade EN-GJL-200. The mean hardness of deposits A-NiCrSiB, C-NiCrSiB is equal to 908 HV, 399 HV and exceeds those of EN-GJL-200 and X5CrNi18-10 reference specimens 197 HV and 209 HV, respectively. To study CE, the vibratory apparatus has been used and tests were conducted according to the ASTM G32 standard. Cavitation eroded surfaces were examined using a profilometer, optical and scanning electron microscopy. The research indicated that the CE resistance, expressed by the cumulative mass loss decreased in the following order C-NiCrSiB > A-NiCrSiB > X5CrNi18-10 > EN-GJL-200. Therefore, hardfacings were characterised by lower cumulative mass loss, in turn, higher CE resistance than the reference sample and therefore they may be applied as layers to increase resistance to cavitation of cast iron machine components. Results indicate that in the case of multiphase materials, hardness cannot be the main indicator for CE damage prediction while it strongly depends on the initial material microstructure. To qualitatively estimate the cavitation erosion damage (CEd) of NiCrSiB self-fluxing alloys at a specific test time, the following factors should be considered: material microstructure, physical and mechanical properties as well as surface morphology and material loss both estimated at specific exposure time. A general formula for the CEd prediction of NiCrSiB deposits was proposed.
Źródło:: Advances in Science and Technology. Research Journal; 2021, 15, 4; 376-386
2299-8624
Pojawia się w:: Advances in Science and Technology. Research Journal
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: Myśl pedagogiczna i edukacja wobec anomii, bierności obywatelskiej, dysfunkcjonalności władzy i demokracji proceduralnej
Pedagogy and education in the face of anomie, civic passivity, dysfunction of power and procedural democracy
Autorzy:: Pilch, Tadeusz
Czerepaniak-Walczak, Maria
Radziewicz-Winnicki, Andrzej
Powiązania:: https://bibliotekanauki.pl/chapters/1040107.pdf
Data publikacji:: 2020-12-11
Wydawca:: Uniwersytet Warszawski. Wydawnictwa Uniwersytetu Warszawskiego
Tematy:: patologia władzy politycznej
mowa nienawiści
nietolerancja
antyreforma oświaty
marginalizacja i wykluczenie
polityka socjalna
zagrożenie ekologiczne
pathology of political power
hate speech
intolerance
marginalization and exclusion
social policy
ecological threat
education anti-reform
Opis:: The article critically analyses political power in Poland. Two charges are formulated against the authorities: 1. lack of rational economic policy, 2. deliberate sparking of hostility and division in the society. These deliberately destructive divisions are accompanied by manipulation of facts, hypocrisy over the past and incitement of hostility on the basis of political, moral and other differences. A bizarre example of the aberration of the country’s political authorities is establishing “LGBT-free zones”. The article presents threats resulting from the introduction of a failed reform of the educational system. This includes the reduction of protective, medical and social functions of the school, and the commercialization of extracurricular activities, thereby increasing educational inequalities. The article sheds a critical light on employment policy, employee protection and working conditions. The scandalous neglect in this respect has led to the highest economic emigration in recent decades, including that of young people. A separate area of criticism is the scandalous neglect of ecology, lack of concern for renewable energy sources, growing exclusion of communication and growing income inequalities, which puts Poland in the group of countries with the highest social stratification rates.
Źródło:: Pedagogika i edukacja wobec kryzysu zaufania, wspólnotowości i autonomii; 153-176
9788323543039
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: Niemcy -- Polska -- Europa 1930-1936 w optyce polskich i niemieckich socjalistów Górnego Śląska i Cieszyńskiego
Autorzy:: Walczak, Jan.
Powiązania:: Z dziejów stosunków polsko-niemieckich / red. Tadeusz Dubicki, Krzysztof A. Kuczyński Łódź, 1998 S. 153-172
Współwytwórcy:: Dubicki, Tadeusz. Redakcja
Kuczyński, Krzysztof A. Redakcja
Opis:: Tekst część. niem. -- streszcz. niem., pol.
Dostawca treści:: Bibliografia CBW

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: Neurological and neurophysiological examinations of workers exposed to arsenic levels exceeding hygiene standards
Autorzy:: Sińczuk-Walczak, Halina
Janasik, Beata M.
Trzcinka-Ochocka, Małgorzata
Stanisławska, Magdalena
Szymczak, Maria
Hałatek, Tadeusz
Walusiak-Skorupa, Jolanta
Powiązania:: https://bibliotekanauki.pl/articles/2179016.pdf
Data publikacji:: 2014-12-01
Wydawca:: Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:: occupational exposure
arsenic speciation
nervous system
neuropathy
neurophysiological test
Opis:: Objectives: The assessment of the neurotoxic effect of arsenic (As) and its inorganic compounds is still the subject of interest due to a growing As application in a large array of technologies and the need to constantly verify the principles of prevention and technological parameters. The aim of this study was to determine the status of the nervous system (NS) in workers exposed to As at concentrations exceeding hygiene standards (Threshold Limit Values (TLV) – 10 μg/m³, Biological Exposure Index (BEI) – 35 μg/l) and to analyze the relationship between the NS functional state, species of As in urine and As levels in the workplace air. Material and Methods: The study group comprised 21 men (mean age: 47.43±7.59) employed in a copper smelting factory (mean duration of employment: 22.29±11.09). The control group comprised 16 men, matched by age and work shifts. Arsenic levels in the workplace air (As-A) ranged from 0.7 to 92.3 μg/m³; (M = 25.18±28.83). The concentration of total arsenic in urine (Astot-U) ranged from 17.35 to 434.68 μg/l (M = 86.82±86.6). Results: Syndrome of peripheral nervous system (PNS) was manifested by extremity fatigue (28.6%), extremity pain (33.3%) and paresthesia in the lower extremities (33.3%), as well as by neuropathy-type mini-symptoms (23.8%). Electroneurographic (ENeG) tests of peroneal nerves showed significantly decreased response amplitude with normal values of motor conduction velocity (MCV). Stimulation of sural nerves revealed a significantly slowed sensory conduction velocity (SCV) and decreased sensory potential amplitude. Neurophysiological parameters and the results of biological and environmental monitoring showed a relationship between $\text{As}^\text{tot}$, $\text{As}^\text{III}$ (trivalent arsenic), the sum of iAs ($\text{As}^\text{III}+\text{As}^\text{V}$ (pentavalent arsenic))+MMA (monomethylarsonic acid) concentration in urine and As levels in the air. Conclusions: The results of the study demonstrate that occupational exposure to inorganic arsenic levels exceeding hygiene standards (TLV, BEI) generates disorders typical of peripheral neuropathy.
Źródło:: International Journal of Occupational Medicine and Environmental Health; 2014, 27, 6; 1013-1025
1232-1087
1896-494X
Pojawia się w:: International Journal of Occupational Medicine and Environmental Health
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Informacja

Wyszukujesz frazę "Walczak, Tadeusz." wg kryterium: Autor

Źródło danych

Dostawca treści

Podbaza

Kolekcja

Rok wydania

Wydawca

Temat

Autor

Typ dokumentu

Język