Filtry
wszystkich: 3299
-
Katalog
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: FEAR OF CHILDBIRTH
-
Exploring the Phenomenon of the Additive Colour Process While Using a Computer Programme by 7–8-Year-Old Students
Publikacja -
Airborne wear particle emission from train brake friction materials with different contents of steel and copper fibres
PublikacjaThis study investigated the influence of the amount of steel and copper fibres in a train brake friction material on the tribological performance, emission intensity and characteristics of airborne wear particles. The particles were generated on a pin-on-disc tribometer under controlled friction and environmental conditions. It was found that the steel fibre results in a more intensive emission of 0.3–10 μm particles compared to...
-
INFLUENCE OF SOLID PARTICLE CONTAMINATION ON THE WEAR PROCESS IN WATER LUBRICATED MARINE STRUT BEARINGS WITH NBR AND PTFE BUSHES
PublikacjaThis paper reports on a study of the influence of solid particle contamination on the wear process in water-lubricated slide bearings (steel-acrylonitrile-butadiene rubber (NBR) and steel- polytetrafluoroethylene (PTFE)). To compare the wear of the shaft journal and bushes (NBR and PTFE) when lubricated with fresh water and contaminated water, an experiment was carried out to identify key factors that influence the state of wear...
-
Dipole-driven dynamics for near-threshold electron/positron interactions with pyrimidinic DNA bases: a path to compound formations
PublikacjaCalculations are reported for electron and positron scattering from isolated cytosine and thymine, where the two pyrimidinic single-ring DNA bases, in the gas-phase at energies near the elastic threshold, they reveal the special features of the dipole-driven scattering states. All molecules examined exhibit, in fact, supercritical (>1.67 D) permanent dipoles which can therefore also support, below threshold, excited bound compound...
-
Tribo-Environment Dependent Chemical Modification of Sliding Interfaces in Ultrananocrystalline Diamond Nanowall Film: A Correlation with Friction and Wear
PublikacjaTribological properties of ultrananocrystalline diamond nanowall (UNCD NW) films were investigated quantitatively in three different and controlled tribo-environmental conditions, proposing the passivation and graphitization mechanisms. However, these mechanisms are rather complicated and possibly can be understood in well-controlled tribological conditions. It was shown that the friction and wear of these films were high in highPage 1...
-
ATTEMPT AT EVALUATING THE INFLUENCE OF BENDING STRESS ON SHAFT WEAR PROCESSES IN WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublikacjaWater lubricated bearings find increasingly wide application in shipbuilding or hydro–power industry, the popularity stemming from their numerous advantages. Unfortunately, as it turns out, water lubricated bearings do not always meet expectations, as on occasion they become subject to intense, premature wear which requires costly repair. One of the still unexplained phenomena is the process of excessive bearing wear, in particular...
-
Modeling of TEC Variations Based on Signals from Near Zenith GNSS Satellite Observed by Dense Regional Network
PublikacjaCurrently the substantial successes in high-resolution ionospheric mapping is declared in many publications. Nevertheless, up to now there are no examples of dynamic visualization of TEC disturbances on regional scale with as high resolution as tropospheric models. Over the years, ionosphere has been modeling basing on the simple assumption, that it is a thin layer, which surrounds the Earth at some arbitrary height. However, the...
-
Mechanical Properties and Wear Susceptibility Determined by Nanoindentation Technique of Ti13Nb13Zr Titanium Alloy after “Direct Laser Writing”
PublikacjaLaser treatment has often been applied to rebuild the surface layer of titanium and its alloys destined for long-term implants. Such treatment has always been associated with forming melted and re-solidified thin surface layers. The process parameters of such laser treatment can be different, including the patterning of a surface by so-called direct writing. In this research, pulse laser treatment was performed on the Ti13Nb13Zr...
-
Modal properties identification of a novel sandwich footbridge – Comparison of measured dynamic response and FEA
PublikacjaA modern sandwich composite footbridge made of high-tech materials, being an example of practical application of laminated composites in civil engineering, is presented. The in situ non-destructive testing of the footbridge, aiming to identify modal properties and pedestrian comfort, is described. The measured eigenmodes and eigenfrequencies are compared with numerically estimated values. Finite element analyses of the footbridge...
-
A Low-Cost System for Far-Field Non-Anechoic Measurements of Antenna Performance Figures
PublikacjaPrototype measurements are the key step in the development of antenna structures. Typically, their far-field characteristics are validated in expensive, dedicated facilities such as open range sites, or anechoic chambers. Despite being necessary for obtaining high-precision data (e.g., for device qualification), the use of costly infrastructure might not be fully justified when the main goal of measurements includes demonstration...
-
Emakeele Seltsi aastaraamat (The Estonian Mother Tongue Society Year Book)
Czasopisma -
Comparative analysis of zinc status, food products' frequency intake and food habits of 11-year-old healthy children
Publikacja -
Determination of API content in a pilot-scale blending by near-infrared spectroscopy as a first step method to process line implementation
PublikacjaNear infrared (NIR) spectroscopy was used for estimation of powder blend homogeneity and manufacturing control of a medicinal product powder mixture containing active pharmaceutical ingredient (API). Aiming at initiating a Process Analytical Technology (PAT) activity, the first step was a stationary mode atline evaluation. In this, the content of pharmaceutical active compound in the powder mixtures intended to the direct tabletting...
-
Friction and wear behaviour of self mated DLC and DLC-W coatings in water or salt in water solution lubricated sliding
PublikacjaPrzedstawiono wyniki badań powłok ceramicznych DLC oraz DLC z wolframem (DLC-W) nałożonych na podłoże ze stali nierdzewnej,przy tarciu ślizgowym , w modelowym skojarzeniu o styku konforemnym (płaskie czoło obracającej się względem swojej osi tulei - powierzchnia płaska). Badania prowadzono stosując smarowanie wodą destylowaną albo wodnym roztworem soli - NaCl. Wyznaczano współczynniki tarcia oraz intensywność zużywania ceramicznej...
-
Modeling flatness deviation in face milling considering angular movement of the machine tool system components and tool flank wear
Publikacja -
Evaluation of physical indicators and tool wear during grooving of spheroidal cast iron with a novel WCCo/cBN (BNDCC) inserts
Publikacja -
Potential of bioethanol production from biomass of various Miscanthus genotypes cultivated in three-year plantations in west-central Poland
Publikacja -
Preliminary Outcomes 1 Year after Laparoscopic Sleeve Gastrectomy Based on Bariatric Analysis and Reporting Outcome System (BAROS)
Publikacja -
Updated 24-year trend of Type 1 diabetes incidence in children in Poland reveals a sinusoidal pattern and sustained increase
Publikacja -
Prediction of near-bottom water salinity in the Baltic Sea using Ordinary Least Squares and Geographically Weighted Regression models
Publikacja -
MOCS-based optimum design of TMD and FTMD for tall buildings under near-field earthquakes including SSI effects
Publikacja -
Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron
PublikacjaThe wear of brakes in transport vehicles is one of the main anthropogenic sources of airborne particulate matter in urban environments. The present study deals with the characterisation of airborne wear microparticles from a low-metallic friction material / cast iron pair used in car brakes. Particles were generated by a pin-on-disc machine in a sealed chamber at sliding velocity of 1.3 m/s and contact pressure of 1.5 MPa. They...
-
Exposure of a small Arctic seabird, the little auk (Alle alle) breeding in Svalbard, to selected elements throughout the course of a year
PublikacjaThe Arctic marine ecosystem can be altered by processes of natural and anthropogenic origin. Spatio-temporal variation in species exposure to contamination is still poorly understood. Here, we studied elemental concentrations in the non-lethally collected samples from the most numerous seabird in European Arctic, the little auk (Alle alle) nesting in one breeding colony in Svalbard. This seabird spent the breeding season in the...
-
The abrasive wear resistance of coatings manufactured on high-strength low-alloy (HSLA) offshore steel in wet welding conditions
PublikacjaSome marine and offshore structure elements exploited in the water cannot be brought to the surface of the water as this will generate high costs, and for this reason, they require in-situ repairs. One of the repair techniques used in underwater pad welding conditions is a wet welding method. This paper presents an investigation of the abrasive wear resistance of coatings made in wet welding conditions with the use of two grades...
-
Experimental analysis of wear resistance of compacts of fine-dispersed iron powder and tungsten monocarbide nanopowder produced by impulse pressing
PublikacjaThe paper presents the results of studying the structure and wear resistance of compacts produced from fine dispersed reduced iron powder (average particle size 3–mu m) with the addition of tungsten carbide (WC) nanopowder with the average particle size of 25–30 nm. The mass fraction of tungsten carbide (wolfram carbide) in the powder composition was 5% and 10% of the total mass. Impulse pressing was conducted using the modified...
-
Methylmercury and total mercury content in soft tissues of two bird species wintering in the Baltic Sea near Gdansk, Poland
PublikacjaOf the various forms of Hg occurring in nature, (mono) methylmercury (MeHg) is an especially toxic form and practically all forms of Hg can be converted into MeHg as a result of natural processes. Total mercury (THg) and MeHg were determined in tissues of two piscivorous birds: razorbill Alca torda and black-throated loon Gavia arctica to provide baseline data on current mercury concentrations for liver, kidneys and pectoral muscle...
-
Lokalizacja obiektu ferromagnetycznego metodą magnetometryczną na równiku = Localization of ferromagnetic objects via magnetometric method near equator
PublikacjaIstnieje wiele metod wykrywania ukrytych w ziemi obiektów. Metody te można podzielić na pasywne i aktywne. Do metod pasywnych należy metoda magnetometryczna. Obiekt ferromagnetyczny zaburza w swoim otoczeniu równomierność pola magnetycznego. Korzystając z metody magnetometrycznej można to zburzenie zmierzyć i wykryć obiekt. W pracy przedstawiono nową metodę lokalizacji obiektów ferromagnetycznych metodą magnetometryczną znajdujących...
-
Technical foundations for noninvasive assessment of changes in the width of the subarachnoid space with near-infrared transillumination-backscattering sounding (NIR-TBSS)
PublikacjaPraca opisuje metodę transiluminacji w bliskiej podczerwieni umożliwiającą nieinwazyjne monitorowanie zmian szerokości przestrzeni podpajęczynówkowej oraz amplitudy tętnienia naczyń powierzchniowych mózgu.
-
EVALUATING THE INFLUENCE OF BENDING STRESS ON A 1H18N9 STEEL SHAFT WEAR PROCESS IN A WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublikacjaThe issue of excessive wear of shaft journals co-working with a rubber bearing has been unexplained so far. Premature and sometimes very intensive wear of ship sliding bearings in water conditions is the reason for carry out very expensive and more frequent than expected repairs. The authors (E. Piątkowska, W. Litwin) made an attempt to find a case that influences the value of this wear described in the paper “Attempt at Evaluating...
-
High-temperature Corrosion of ~ 30 Pct Porous FeCr Stainless Steels in Air: Long-Term Evaluation Up to Breakaway
PublikacjaIn this work, a long-term (up to 6000 hours) corrosion evaluation of three porous (~ 30 pct of initial porosity) ferritic iron-chromium alloys with different Cr contents (20, 22, and 27 wt pct of Cr) was carried out at 600 C, 700 C, 800 C, and 900 C in air. Mass gain measurements and SEM analyses revealed that at temperatures above 600 C, all alloys exhibit breakaway corrosion, whereas at 600 C, none of the alloys were heavily...
-
Per far midaglie di gesso: Giovanni Bernardino Bonifacio i sztuka portretu all'antica.
Publikacja -
ADAPTATION OF ENGINEERING FEA-BASED ALGORITHMS TO LCF FAILURE AND MATERIAL DATA PREDICTION IN OFFSHORE DESIGN
PublikacjaThere is an ever growing industrial demand for quantitative assessment of fatigue endurance of critical structural details. Although FEA-based calculations have become a standard in engineering design, problems involving the Low-To-Medium cycle range (101-104) remain challenging. This paper presents an attempt to optimally choose material data, meshing density and other algorithm settings in the context of recent design of the...
-
Effects of renal denervation on kidney function and long-term outcomes: 3-year follow-up from the Global SYMPLICITY Registry
Publikacja -
Clinical characteristics of patients with neurogenic bladder due to myelomeningocele – Eighteen-year retrospective study; University Children's Hospital, Bialystok, Poland
Publikacja -
Assessment of cross compatibility of pear (Pyrus communis L.) cultivars on the basis of pollen tube observations and analysis of the S-RNase gene
Publikacja -
Orthodontic characteristics of maxillary arch deficiency in 5-year-old patientsundergoing unilateral cleft lip and palate repair with and withoutearly gingivoplasty
Publikacja -
Ex-athletes as Parents Promoting Healthy Lifestyles in Their Families: The Nutrition and Physical Activity of Mothers, Fathers, and 6-Year-Old Children
Publikacja -
Methodology for carrying out measurements of the tombolo geomorphic landform using Unmanned Aerial and Surface Vehicles near Sopot pier, Poland
Publikacja -
Recreation of Construction Patterns by 4-, 5- and 6-year-old Children 70 Years Ago and Today. Comparison of Test Results
Publikacja -
Effects of near-bottom water oxygen concentration on biogeochemical cycling of C, N and S in sediments of the Gulf of Gdansk (southern Baltic)
Publikacja -
Improved Procedures for Feature-Based Suppression of Surface Texture High-Frequency Measurement Errors in the Wear Analysis of Cylinder Liner Topographies
Publikacja -
Fragility analysis of structural pounding between adjacent structures arranged in series with various alignment configurations under near‑field earthquakes
PublikacjaA major cause of local to total damages is related to structural pounding in a large number of past earthquakes. In general, these collisions take place as a result of differences in the dynamic characteristics of the colliding structures. To acquire a better perception of the behavior of structures, in this paper, three structures featuring different heights are modeled in series and with various configurations next to each other...
-
Experimental research on water lubricated marine stern tube bearings in conditions of improper lubrication and cooling causing rapid bush wear
PublikacjaWater lubricated bearings are popular in sliding bearings of marine propeller shafts, turbines and pump shafts. Such popularity is partly due to their simple construction which also means a relatively affordable price. In practical experience one may also observe cases of rapid wear or even malfunctions of this bearings, some of which may be caused by insufficient flow of lubricant leading to overheating. The conducted...
-
Artificial neural network model of hardness, porosity and cavitation erosion wear of APS deposited Al2O3 -13 wt% TiO2 coatings
Publikacja -
Emission and properties of airborne wear particles from train brake friction materials based on novolac phenolic resins and butadiene rubbers
PublikacjaThe emission of airborne particulate matter from a train brake depends on the formulation of its friction material. This study investigates the emission and properties of wear particles from train brake friction materials based on straight or resorcinol-modified novolac phenolic resin and nitrile or styrene butadiene rubber used as binding ingredients. The wear particles are generated by a pin-on-disc tribomachine inside an aerodynamic...
-
Monitoring strategy for industrially contaminated rivers - A study of all year round behaviour of Klodnica river catchment, upper Silesia, Poland
PublikacjaThe study was undertaken to thoroughly characterise the contamination of water in industrially influenced river Klodnica, in order to explore monitoring strategies in case of limited analytical capacity. Statistical analysis undertaken after a short study was found to be helpful in reducing monitoring efforts in the future.Klodnica river is located within area of dominating coal mining, metallurgy, and additionally being influenced...
-
Surgical Site Infection after Breast Surgery: A Retrospective Analysis of 5-Year Postoperative Data from a Single Center in Poland
PublikacjaBackground and Objectives: Surgical site infection (SSI) is a significant complication of non-reconstructive and reconstructive breast surgery. This study aimed to assess SSI after breast surgery over five years in a single center in Poland. The microorganisms responsible for SSI and their antibiotic susceptibilities were determined. Materials and Methods: Data from 2129 patients acquired over five years postoperatively by the...
-
Methodology for Carrying Out Measurements of the Tombolo Geomorphic Landform Using Unmanned Aerial and Surface Vehicles near Sopot Pier, Poland
PublikacjaThe human impact on the ecosystem has been particularly evident in the last century; it transforms the Earth’s surface on an unprecedented scale and brings about irreversible changes. One example is an oceanographic phenomenon known as a tombolo, i.e., a narrow belt connecting the mainland with an island lying near the shore formed as a result of sand and gravel being deposited by sea currents. The phenomenon contributes to an...
-
Evaluation the P-Delta Effect on Collapse Capacity of Adjacent Structures Subjected to Far-field Ground Motions
PublikacjaIn urban areas, adjacent structures can be seen in any insufficient distance from each other, because of economic reasons and refusal of acquired minimum separation distance according to seismic previsions. Collapse capacity assessment of structures is one of the important objectives of performance-based seismic engineering. The purpose of this study is to consider the pounding phenomenon and P-Delta effect in seismic collapse...
-
Evaluation the P-Delta Effect on Collapse Capacity of Adjacent Structures Subjected to Far-field Ground Motions
Publikacja