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1
Content available remote Monte Carlo study of medium-energy electron penetration in aluminium and silver
100%
Nukleonika
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2015
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tom 60
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nr 2
361-366
EN
Monte Carlo simulations are very useful for many physical processes. The transport of particles was simulated by Monte Carlo calculating the basic parameters such as probabilities of transmitted–reflected and angular-energy distributions after interaction with matter. Monte Carlo simulations of electron scattering based on the single scattering model were presented in the medium-energy region for aluminium and silver matters. Two basic equations are required the elastic scattering cross section and the energy loss. The Rutherford equation for the different screening parameters is investigated. This scattering model is accurate in the energy range from a few keV up to about 0.50 MeV. The reliability of the simulation method is analysed by comparing experimental data from transmission measurements.
EN
The evaluation of skin penetration of active substances from topical preparations is a pre-clinical requirement in the pharmaceutical industry. While in vitro preparations of human or animal skin are frequently used the development of artificial lipophilic and hydrophilic membranes with similar properties to human or animal skin need to be developed. This preliminary study compared the in vitro permeation of niacinamide (vitamin B3), which is used as a model drug, across artificial hydrophilic and lipophilic membranes with iv vitro penetration across human skin. The experiments were carried out in Franz diffusion cells. Artificial membranes were filter paper impregnated with either collodium (hydrophilic), stearic acid, cetyl alcohol or cetyl alcohol + cholesterol (lipophilic). Acidic and neutral hydrogel and emulsion (pH 5.4 and 7.4) containing 0.5% of niacinamide were applied to membranes for up to 4 hours. Niacinamide permeated hydrophilic better than lipophilic membranes. There were no significant differences between the cumulated amounts of niacinamide that penetrated artificial lipophilic membranes consisting of, stearic acid, cetyl alcohol and cholesterol as compared with human skin in vitro. Also, hydrogel and emulsion solvents gave similar results. In conclusion, these artificial membranes seem to be a promising alternative to human or animal skin.
3
86%
EN
Aim: The aim of the study was to determine the prevalence of dysphagia in patients with chronic cough. Material and methods: Thirty-four consecutive patients. All patients underwent physical examination, ENT assessment, functional phoniatric assessment at rest and speech, Water-Swallow Test (WST), and Fiberoptic Endoscopic Evaluation of Swallowing Disorders (FEES). Furthermore, Reflux Symptom Index (RSI) and Eating Assessment Tool 10 (EAT 10) questionnaires were performed. Results: Results of the RSI and EAT 10 questionnaires showed the risk of reflux and dysphagia in participating patients. WST positive results increase with water volume. Patients presented episodes of spillage, double swallows, penetration, aspiration and residue of food at the hypopharynx. Functional examination showed decrease of laryngeal elevation (33%) and hypertension of external laryngeal muscles. Conclusions: Results of the study showed prevalence of dysphagia in most patients with chronic chough. It seems that phoniatric assessment in those cases should be expanded and FEES examination should comprise an important part.
EN
Endoscopic examination of swallowing FEES (fiberoptic endoscopic examination of swallowing) belongs to basic instrumental examinations used in diagnostics of oropharyngeal dysphagia. It consists of three parts: I. Evaluation of the anatomy and physiology of the throat and larynx; II. Assessment of drinking and eating liquids and foods with different consistencies; III. Evaluation of the effectiveness of therapeutic maneuvers. The work aims to present the test procedure and the form used to describe it.
PL
Przestawiono przykłady obliczeń projektowej straty ciepła przez przenikanie wg normy PN-EN 12831. Wyniki porównano z wynikami, uzyskanymi wg PN-B-03406:1994.
EN
Computational examples of the designed heat penetration loss, according to the PN-EN 12831 Standard, are presented. The results have been compared with those achieved according to the PN-B-03406: 1994 Standard.
PL
W artykule przestawiono metodę obliczania projektowej straty ciepła przez przenikanie wg normy PN-EN 12831.
EN
A method of calculation, concerning the designed losses of heat penetration according to the PN-EN 12831 Standard, is presented.
8
Content available remote Urządzenie do oceny konsystencji plastycznych środków smarowych
72%
PL
W artykule omówiono model odkształcenia smaru plastycznego pod wpływem zagłębiania w nim obciążonego stożka. Głębokość zanurzenia stożka jest proporcjonalna do działającej siły i zależna od spójności wewnętrznej smaru. Zależność ta pozwala na określenie konsystencji badanego smaru. W oparciu o wyznaczone relacje matematyczne przedstawiono rozwiązania konstrukcyjne elementów pomiarowych, które zastosowano w opracowanym automatycznym penetrometrze. Metodami statystycznymi wykazano, iż zbudowany aparat zapewnia wymaganą precyzję i dokładność pomiaru penetracji smarów plastycznych.
EN
This article presents model of a grease distortion under the influence of loaded cone penetration. Cone penetration depth is proportional to operative forces and it dependants on greases internal cohesion. This dependence to let qualification consistency of studding greases. Basing oneself on the calculation mathematics relations the constructional solutions of measuring elements has been proposed. It was employed in elaborating automatic penetrometers. By using statistical methods it has been proved, that structured instrument secures required precision and accuracy of grease measurement penetration.
PL
Niniejszy artykuł stanowi przyczynek do problemu dominacji rosyjskiej w Europie Wschodniej po rozpadzie ZSRR, dotychczas rzadko podejmowanego w takim ujęciu przez badaczy. W tekście zawarto rozważania nawiązujące do dwóch pytań: dlaczego warto podjąć tytułowy problem oraz jakie mogą być ścieżki metodologiczne w tego typu badaniach? Po 1992 r. Rosja prowadzi specyficzną politykę wobec państw Europy Wschodniej wynikającą z uwarunkowań historycznych oraz mocarstwowych ambicji władców Kremla. Zmiany na arenie międzynarodowej w 2014 r. stworzyły przesłanki do zbadania polityki Federacji Rosyjskiej wobec państw Europy Wschodniej. Nowa sytuacja geopolityczna wymaga również stosowania takich metod badawczych, które pozwoliłyby na pełne wyjaśnienie tych relacji. W procesie analizy należy przyjąć, że podmiotem działania jest Rosja, przedmiotem są natomiast Ukraina, Białoruś i Mołdawia. Kontynuując badania dotyczące dziejów tych państw, należałoby jeszcze dokładniej zbadać obszary dysfunkcjonalności systemu poradzieckiego oraz określić, na ile trwałe było przeniknięcie struktur penetrujących do wnętrza systemów państw Europy Wschodniej, a także, w jakim zakresie po 1991 r. nastąpiło „cofnięcie” regulatora?
EN
The article refers to a rarely undertaken by analysts approach to the problem of the Russian domination over Eastern Europe after the collapse of the Soviet Union. The text deals with two basic questions: why the problem of the Russian domination should be the topic of any research and what methodological approaches should be used in such studies? After 1992 Russia has been carrying out a very specific policy towards the countries of Eastern Europe, which arises from historical context and the Kremlins’ rulers’ imperial ambitions. Changes at the international arena in 2014 created conditions for investigating the Russian Federation policy towards the countries of Eastern Europe. The new geopolitical situation also requires the application of such research methods that would allow a full explanation of new political relations. In the process of analysis it should be assumed that Ukraine, Belarus and Moldova are passive subjects of the actions carried out by Russia. Further research of the history of these countries would require investigating the areas of dysfunctionality of the post-Soviet system and determining, to what extent Eastern Europe state systems could be penetrated and to what extent the Russian control was retracted after 1991.
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2006
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tom nr 5
97-109
PL
W publikacji opisano charakterystyczne właściwości smaru przeznaczonego do łożysk tocznych pracujących w temperaturach poniżej -45°C. Określono właściwości niskotemperaturowe opracowanych smarów plastycznych na bazie składników syntetycznych, wyznaczając moment obrotowy w chwili rozruchu i po 1 h pracy oraz penetrację w temperaturach ujemnych. Zbadano wpływ smaru niskotemperaturowego na trwałość węzła tarcia, jego właściwości przeciwzużyciowe i przeciwzatarciowe oznaczając graniczne obciążenie zużycia oraz graniczny nacisk zatarcia w warunkach zacierania. Parametry użytkowe opracowanych niskotemperaturowych smarów plastycznych porównano z parametrami smaru o podwyższonej odporności na działanie niskich temperatur. W wyniku przeprowadzonych badań stwierdzono, że opracowane smary plastyczne spełniają wymagania przewidziane dla smaru do łożysk tocznych pracujących w temperaturach do -54°C.
EN
There was described characteristic properties of the grease designed for rolling bearings working at temperatures below-45°C. The low-temperature properties of elaborated greases were determined on the base of low-temperature torque and penetration at temperatures below 0°C. The influence of elaborated low-temperature greases on the durability of tribological couple and their antiwear and antiseizure properties was determined using limiting load of were and limiting pressure of seizure. It has been ascertained that elaborated greases have properties provided for a rolling bearing grease working at temperature above - 54°C.
EN
Impact of powders and sewing needles accelerated by explosion on various obstacles has been studied. Formation of channels up to 100 particle diameters in length has been observed when corundum and tungsten powders impacts on steel and duralumin at speeds up to 2 km/s. A mechanism of such super deep penetration of powder jets into metals has been proposed. The possibility of destroying by needles such objects as plexiglass blocks, antimeteorite screens, containers with elastic and explosive materials with a released energy exceeding the energy of needles has been shown. At impact speeds up to 400 m/s the depth of needles penetration into metals is 3-5 times higher than the one calculated for pointed rods at plastic work. The obtained results can be useful for modeling of impact of meteorites, space scraps and technological wasteson space aircrafts and their components.
PL
Przedstawiono problematykę dotyczącą okrętowych osłon balistycznych zilustrowaną przykładami perforacji i penetracji. Podano zasadnicze modele znane z literatury penetracji i perforacji. Zaprezentowano teoretyczne krzywe penetracji dla dynamicznej wytrzymałości materiałów. Dokonano próby opisu wyników eksperymentalnych za pomocą znanych modeli.
EN
The issues concerning the ballistic protection shield are illustrated by the examples of penetration and perforation. The essential models known from the literature regarding the penetration and perforation are explained. The theoretical penetration characteristics for the dynamic endurance of materials are presented. There is an attempt to describe the experimental results by the means of the known models.
13
Content available remote Struktura przenikania kropel cieczy w lotnych zabiegach ochrony lasów
58%
PL
Przedstawiono rezultaty badań struktury oprysku w zabiegach nad lasem, wykonanego rolniczymi statkami powietrznymi z zabudowanymi rozpylaczami obrotowymi (atomizerami) i ciśnieniowymi. Stosowano dawki 1,6 dm3/ha. Określono przenikanie kropel przez korony drzew.
EN
Paper presented the results of experiments with aerial spraying of conifer forest. An agricultural aeroplain and helicopter were used, both equiped with rotary (atomizer) and pressure nozzles. Liquid doses of 1.6 dm3/ha were applied. The structure of droplets and their distribution into crowns of the pine trees were measured. No segregation of liquid droplets was observed at their penetration into pine crownes.
EN
Purpose: Plasma Transferred Arc surfacing is increasingly used in applications where enhancement of wear, corrosion and heat resistance of materials surface is required. The shape of weld bead geometry affected by the PTA Welding process parameters is an indication of the quality of the weld. In the paper the modelling, analysis and optimization of weld bead parameters of nickel based overlay deposited by plasma transferred arc surfacing are made. Design/methodology/approach: The experiments were conducted based on a five factor, five level central composite rotatable design and a mathematical model was developed using multiple regression technique. The direct and interaction effects of input process parameters of PTA Hardfacing on weld bead geometry are discussed. Finally, Microsoft Excel Solver has been used to optimize the process parameter with a view to economize the powder and achieve the desirable bead dimensions. Findings: Penetration, dilution and total area are increased when the welding current is increased but reinforcement marginally increases and then decreases. Penetration, weld width, dilution and total area decrease when travel speed is increased. Reinforcement increases slightly and then decreases. Practical implications: The developed mathematical models can be used to predict the dimensions of the weld bead and dilution. Originality/value: This paper highlights the development of a mathematical model correlating various process parameters to weld bead geometry in PTA hardfacing of Colmonoy 5, a Nickel based alloy over Stainless steel 316 L plates.
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