bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication of Nanostructured Gradient Tungsten-Cobalt Alloy Using Carbon Deficiency Powder
Authors: Dvornik Maksim , Mikhailenko Elena
Published: September 2018

A nanostructured functionally graded hard alloy was obtained by sintering at temperatures from 1350 to 1410 ° C of two-layer "green bodies", each consisting of layer of powder with normal carbon content (WC-15Co-0.4VC-0.4Cr2C3) and powder layer with deficit of carbon (WC-8Co-0.4VC-0.4Cr2C3). The formation of the η phase (Co3W3C) in the layer with cobalt deficiency causes the migration of cobalt to it and prevents the return of cobalt back in a wide temperature range of temperatures (1350-1410). The porosity of the resulting nanocrystalline hard alloy at 1410 ° C is reduced to 2%, and the maximum hardness of the surface layer with a low cobalt content (10%) reaches 1945HV.
Comparison of Crystal and Phonon Structures for Polycrystalline BaSi2 Films Grown by SPE Method on Si(111) Substrate
Authors: Galkin Nikolay G. , Fomin Dmitrii Vladimirovich , Dubov Victor Leonidovich , Galkin Konstantin N. , Pyachin Sergey Anatolyevich , Burkov Alexander
Published: September 2018

The search for inexpensive and efficient methods of forming thin BaSi2 films as a promising material for photovoltaic is an actual task. The co-deposition of Ba and Si atoms with alloy thickness of 100-120 nm on the silicon substrate at room temperature with following annealing (SPE method) was proposed. Ba-Si alloy compounds then were thermally annealed at different temperatures and three samples were formed: #1 at T = 600 ° C, #2 at T = 700 ° C and #3 at T = 800 ° C. Polycrystalline films with an orthorhombic BaSi2 structure were formed by XRD, UV-VIS, FIR and Raman spectroscopies data. BaSi2 grains in samples #1 and #2 have sizes 62-64 nm and 86 nm in the sample #3 from XRD data calculations by Scherrer formula. Proposed growth method resulted to strong compression of the BaSi2 unit cell volume on 1.78 – 2.70%. The strongest compression was observed after annealing at 800 °C, which was accompanied by desorption of a noticeable amount of barium and a strong decrease in the film thickness in the sample #3. The formation of nanosize Si clusters was confirmed by Raman data for samples #2 and #3, but they did not observed in the sample #3. So, the film, formed at 800 °C, is the most qualitative in terms of structure and single-phase BaSi2, but with strong decrease of initial Ba-Si alloy thickness due to Ba desorption.
Study of Sodium Adsorption on Pb/Si(111) Surfaces
Authors: Ryzhkova Maria Valeryevna , Tsukanov Dmitry Anatolyevich , Borisenko Elena Anatolyevna , Ivanchenko Maxim Viktorovich
Published: September 2018

The new reconstructions formed by sodium adsorption on Pb-terminated Si (111) surface were obtained: 2x2+2sqrt3x2sqrt3, 4x1, 3x3 and others. These surface structures have been observed by low-energy electron diffraction (LEED) and phase diagram for 2D binary (Na,Pb)/Si (111) system has been obtained. The (Na,Pb)/Si (111) system is considered as a two-dimensional alloy layer with highly ordered structure. Influence of two-dimensional alloys on surface conductivity of Si (111) substrate has been studied in situ by four-point-probe method.
Enhanced Optical Properties of Silicon Based Quantum Dot Heterostructures
Authors: Dvurechenskii Anatoly , Yakimov Andrew , Kirienko Victor , Bloshkin Alekcei , Zinovyev Vladimir , Zinovieva Aigul , Mudryi Alexander
Published: September 2018

New approaches to enhance properties of silicon based quantum dot heterostructures for optical device application were developed. That is strain driven heteroepitaxy, small-sized quantum dots, elemental compositions of the heterointerface, virtual substrate, plasmonic effects, and the quantum dot charging occupation with holes in epitaxially grown Ge quantum dots (QDs) on Si (100). Experiments have shown extraordinary optical properties of Ge/Si QDs heterostructures and mid-infrared quantum dot photodetectors performance.
Comparative Analysis of the Effect of Immersion of Porous Silicon in Aqueous Solutions of Li and Fe Salts on the Stability, Peak Position and Intensity of its Photoluminescence
Authors: Galkin Nikolay G. , Yan Dmitrii Tkhyarbonovich , Galkin Konstantin N. , Chusovitin Evgeniy Anatolievich , Bozhenko Mikhail Victorovich
Published: September 2018

In the process of comparative studies of immersing layers of porous silicon (PS) in aqueous solutions of LiBr and Fe (NO3)3 with subsequent long-term storage up to 150 days, it is established that there exists: (1) the range of concentrations of LiBr (S/2 - S/4) and Fe (NO3)3 (0.2 M), which provide the maximum increase in the intensity of PL; (2) at low concentrations of both salts, a blue shift of the PL peaks and an increase in their intensity are observed during the long-term storage, which is associated with a decrease in the size of the NC in the PS and the influence of silicon bonds with lithium or iron ions; (3) full protection of the PS layer is observed in case of immersion in Fe (NO3)3 with a concentration of 0.7M - 0.8M.
SWIR-NIR Highly Absorbent Si1-xSnx Alloy Film on Si(100) Substrate: Crystal Structure, Optical Properties and Thermal Stability
Authors: Dotsenko Sergei Andreevich , Goroshko Dmitrii L'vovich , Chusovitin Evgeniy Anatolievich , Kitan Sergei A. , Galkin Konstantin N. , Galkin Nikolay G.
Published: September 2018

Thin (200-600 nm) Si-Sn alloy films were grown under ultrahigh vacuum conditions by co-deposition of Si and Sn on the Si (100) substrate at room temperature. Investigations of the film structure by X-ray diffraction showed the preservation of the amorphous structure of Si-Sn films without the contribution of the Si1-xSnx alloy with sphalerite lattice at Sn concentration in the range of x=0.14-0.19. Analysis of optical spectra and calculations showed that an amorphous Si-Sn film with a Sn concentration of 19% is a semiconductor with indirect fundamental optical transition with very high absorption at photon energies 0.2 – 1.0 eV. It was found that precipitation of β-Sn occurs with an increase of Sn concentration up to 40%, which is accompanied by an increase in the reflection coefficient to 0.6-0.8 at photon energies below 0.8 eV. The limited temperature stability of amorphous Si-Sn films is shown for high-energy and long-term (10 minutes) laser irradiation due to the formation of metallic precipitates of β-Sn.
Synthesis of Cyanate Ester Based Thermoset Resin by Using Copper (II) Oxalate as Catalyst and its Application in Carbon Fiber Composites
Authors: Shah Syed Sajid Ali , Nasir Habib , Ul-Haq Noaman
Published: September 2018

Polymer matrix plays a crucial role in the development of advanced light weight composite materials, and is mainly responsible for thermal and mechanical properties. These polymer matrices are usually thermosetting plastics due to their ease of processing. Thermoset resins were prepared using different compositions of dicyanate ester of bisphenol A and polyether imide and carbon fiber laminates were prepared by wet layup technique. Small amount of epoxy (diglycidyl ether of bisphenol A) was also added to the composites to improve the (interfacial) bonding between the carbon fiber and the resin. The Copper (II) oxalate with 1,5-pentanediol was used as a catalyst for the first time to reduce the curing time from eight hours to four hours. The catalyst has also reduced the curing temperature from 400°C to 250°C. The catalyst Copper (II) oxalate is commercially available. The plasticizer has improved the thermal and mechanical properties of the matrix significantly. The addition of epoxy to the thermoset resin improved the (interfacial) bonding between the resin and carbon fiber. FTIR results suggest that the polymerization reaction of dicyanate results in the formation of trizine ring with phenolic group. SEM results show the interaction of bisphenol A dicyanate (BPADCy) monomer to form polymer matrix. SEM images also represent a uniform anchoring of matrix on the individual carbon filament. It is clear from thermal analysis that sample having 85% BPADCy and 15% polyetherimide (BPR-2) shows the greater thermal stability which is due to the reaction of epoxy with cyanate matrix.
Moving from faith-based concerns to demarginalising youths through the Circle of Courage
Authors: Beukes Jacques , Van der Westhuizen Marichen
Published: September 2018

Although the demarginalisation of youths is an international concern, South African youths are viewed by various scholars and policy documents as a particularly vulnerable and marginalised group. It becomes essential to understand what characterises their marginalisation in order to find innovative ways to work towards their demarginalisation. In this article we reflect on current faith-based concerns and compare this with the specific characteristics of the marginalisation of young people. In an effort to contribute to the development of a strategy towards demarginalisation, we will explore the key features of the Circle of Courage in terms of the principles of belonging, mastery, independence and generosity. We will further propose the inclusion of Ubuntu principles in the practical application of the Circle of Courage for churches and faith-based organisations in demarginalising youth in the South African context.
Tonal responses of metally retarted brain-injured children
Authors: Bradley Betty Hunt
Published: September 2018

No abstract available.
Glossectomy
Authors: Whiting Diana M.
Published: September 2018

No abstract available.
Discussion of Mrs. E. M. Harrison's paper
Authors: Office Editorial
Published: September 2018

No abstract available
The electrical activity of the brain in some disorders related to communication
Authors: Nelson G. K.
Published: September 2018

No abstract available.
The relationships between measurements of stuttering behaviour
Authors: Aron Myrtle L.
Published: September 2018

No abstract available.
The austistic child: An approach to handlimg
Authors: Izikowitz Joyce
Published: September 2018

No abstract available.
A survey of surgical procedures for the relief of deafness due of otosclerosis
Authors: Haynes D. R.
Published: September 2018

No abstract available.
General and differential therapy in the field of logopedics and phoniatrics
Authors: Trojan F. , Weihs H.
Published: September 2018

No abstract available.
Cleft lip and palate
Authors: Walker D. H.
Published: September 2018

No abstract available.
A neurological approach to speech therapy for the cerebal palsied
Authors: Jacobs Ruth
Published: September 2018

No abstract available.
Some reflections on the genetics of mental disorder
Authors: Anderson Ingram F.
Published: September 2018

No abstract available.
Metrological performance of single-jet water meters over time
Authors: Palau Carmen Virginia , Manzano Juan , Peralta Iban Balbastre , Azevedo Benito Moreira de , Bomfim Guilherme Vieira do
Published: September 2018

To maintain quality measurement of water consumption, it is necessary to know the metrology of single-jet water meters over time. Knowing the accuracy of these instruments over time allows establishing a metrological operation period for different flow rates. This will aid water companies to optimize management and reduce economic losses due to unaccounted water consumption. This study analyzed the influence of time on the measurement error of single-jet water meters to evaluate the deterioration of the equipment and, with that, launch the metrological operation period. According to standards 8316 and 4064 of the International Organization for Standardization (ISO), 808 meters of metrological Class B were evaluated in six water supplies, with age ranges of 3.7 to 16.4 years of use. The measurement error was estimated by comparing the volume measured in a calibrated tank with the volume registered by the meters at flow rates of 30, 120, 750 and 1,500 L h-1. The metrological operation period of the meters was obtained for each flow rate by the relation between error of measurement and time of use (simple linear regression). According to the results, the majority of the equipment presents increasing under-registration errors over time, more pronounced at low flow rates and with less favorable operating conditions. The metrological operation period for flow rates of 30, 120, 750 and 1,500 L h-1 is estimated at approximately 3, 8, 14 and 13 years. This operation period combined with consumption patterns of users will establish the best time to replace the meters.
Veelheid van identiteiten, fundamentele identiteit en dualisme
Authors: van Woudenberg René
Published: September 2018

Plurality of concepts of identity, foundational identity, and dualism

This paper defends three claims. One: the Dutch word for ‘identity’ (viz. ‘identiteit’) is used to express very different concepts, such as the concept of ‘character’, ‘self-image’, ‘social identity’, ‘narrative identity’, and ‘identity through time’. Two: each of these concepts is applicable to human persons, but the concept of ‘identity through time’ is, in a crucial respect, more fundamental than the others. Three: because the fundamental concept of identity applies to human persons, dualism is to be preferred over physicalism.
Identiteit als expressie
Authors: Halsema Annemie
Published: September 2018

Identity as expression: Narrativity, embodiment, and intersectionality

How to understand intersectional aspects of personal identity such as gender, race or ethnicity, sexual orientation, age and (dis)ability? In this paper, I argue that it requires a notion of personal identity as expression to do so. Most philosophical theories of personal identity do not take into account social, embodied factors such as the ones named above. In order to consider these, I suggest to start from philosophical accounts of narrative identity, notably Schechtman’s and Ricoeur’s. Instead of taking narrative identity to be exhaustive, I propose to understand it as the expressed aspect of personal identity. Identity as expression does not only pertain to linguistic utterances, but also to the body. In the paper, I derive a notion of the body as ontological ground for sociality from Ricoeur’s philosophy, which includes that our body primordially is body among other bodies and makes us part of a community. Ricoeur still thinks embodiment in a general sense, however, and does not reflect upon its being gendered, being assigned a race or ethnicity, etc.. In the final part of the paper, I suggest to turn to Sartre’s philosophy of the body, because he considers this social dimension of embodiment. His notion ‘unrealizables’ offers interesting opportunities to incorporate the view of others upon us into our self-conception. Intersectional aspects of personal identity such as gender, race, etc. consequently should be seen as factors that we do not experience in the first person, but that form the limits of who we are assigned to by others, that we cannot avoid taking a position towards.
The Heart of the Race: Black women contesting British imperialism and whiteness
Authors: Ohene-Nyako Pamela
Published: September 2018

In this paper, my aim is to present what I call Third-World feminist internationalism, which stemmed from the Black Power Movement and the Black Women’s Movement in Britain in the 1970s and 1980s. More precisely, I look at the ways this political articulation is essential to a historicised understanding of the book The Heart of the Race, and especially its authors’ analysis and contestation of British imperialism and whiteness.
Muslim clothing and Swedish whiteness
Authors: Jakku Nina
Published: September 2018

This article discusses social positions of Swedish female converts to Islam who have previously passed as white majority Swedes, but whose experiences have changed, sometimes radically, since donning the hijab. It addresses their accounts of being treated and evaluated differently by teachers, co-workers, family, and friends, and having their choices questioned by strangers. It also examines the double standards that white converts to Islam must negotiate when dealing with daily life in Sweden, and how becoming a Muslim leads to frequent exclusion from constructed whiteness and Swedishness and the privileges attached to those positions.
Photocurrent modelling and experimental confirmation for meteoric smoke particle detectors on board atmospheric sounding rockets
Authors: Giono Gabriel , Strelnikov Boris , Asmus Heiner , Staszak Tristan , Ivchenko Nickolay , Lübken Franz-Josef
Published: September 2018

Abstract. Characterising the photoelectron current induced by the Sun's UV radiation is
crucial to ensure accurate daylight measurements from particle detectors.
This article lays out the methodology used to address this problem in the
case of the meteoric smoke particle detectors (MSPDs), developed by the
Leibniz Institute of Atmospheric Physics in Kühlungsborn (IAP) and flown
on board the PMWEs (Polar Mesosphere Winter Echoes) sounding rockets in
April 2018. The methodology focuses on two complementary aspects: modelling
and experimental measurements. A detailed model of the MSPD photocurrent was
created based on the expected solar UV flux, the atmospheric UV absorption as
a function of height by molecular oxygen and ozone, the photoelectric yield
of the material coating the MSPD as a function of wavelength, the index of
refraction of these materials as a function of wavelength and the angle of
incidence of the illumination onto the MSPD. Due to its complex structure,
composed of a central electrode shielded by two concentric grids, extensive
ray-tracing calculations were conducted to obtain the incidence angles of the
illumination on the central electrode, and this was done for various orientations of
the MSPD in respect to the Sun. Results of the modelled photocurrent at
different heights and for different materials, as well as for different
orientations of the detector, are presented. As a pre-flight confirmation, the
model was used to reproduce the experimental measurements conducted by
Robertson et al. (2014) and agrees within an order of magnitude. An
experimental setup for the calibration of the MSPD photocurrent is also
presented. The photocurrent induced by the Lyman-alpha line from a deuterium
lamp was recorded inside a vacuum chamber using a narrowband filter, while
a UV-sensitive photodiode was used to monitor the UV flux. These
measurements were compared with the model prediction, and also matched within
an order of magnitude. Although precisely modelling the photocurrent is a
challenging task, this article quantitatively improved the understanding of
the photocurrent on the MSPD and discusses possible strategies to untangle
the meteoric smoke particles (MSPs) current from the photocurrent recorded
in-flight.
Disoriented Life
Authors: Rutland Ted
Published: September 2018

This article reviews Ami Harbin’s recent book, Disorientation and Moral Life. It summarizes and affirms the book’s attention to the moral and political significance of moments of disorientation, moments in which people lack certainty regarding what to do, how to do it, or both. It also suggests two ways in which the book’s analysis could be extended, including an exploration of more extensive and systemically produced disorientations.
Expectation and Reality: the Situation of Constructions Sites of the Ministry of Education in Brazil
Authors: Marin Tany Ingrid Sagredo , Lopes Ana Caroliny Conde , Serra Alexandre Rodrigues
Published: September 2018

In 2015, the Ministry of Education (MEC)  created the Integrated Monitoring and Control System (SIMEC), an operational and management tool that shows the situation of education-related constructions under city hall management on their website. The city hall managers fill the information on the system. Therefore, we wonder if the constructions´ situation pointed out by Simec reflects their real conditions. The research aims to learn the real situation of constructions described on Simec using on-site survey, observation, photographic record, and, whenever possible, using mobile applications like "Tá de Pé" (It's on) from "Transparência Brasil" (NGO) or "Eu Fiscalizo" (I supervise) from Federal General Accounting Office (a.k.a TCU in Brazilian Portuguese acronym) to send the findings. We inspected nineteen construction sites in four cities in the State of Pará. The results indicate that the situation of most of them (11 of 19) does not correspond to the information filled by the public agents in Simec. The situation indicates an absence of internal controls in MEC during the supervision of the constructions sites. Thus, we want to raise awareness about the change that can be made in society by engaged and empowered actors of social control.
Measuring Racial Bias and General Education Assessment
Authors: Blankenberger Bob , McChesney Kay Young , Schnebly Stephen Michael , Moranski Karen R. , Dell Heather
Published: September 2018

In this article we discuss a model for assessing general education student learning outcomes related to reducing racial bias in postsecondary students. As many postsecondary institutions do, our institution attempts to address racial bias through our general education curriculum, but it is difficult to assess improvement in this area. We used the Color-Blind Racial Attitude Scale (CoBRAS) assessment tool to analyze changes in racial bias as a general education student outcome. Results of a linear regression model with a number of covariates indicated that passing a Global Awareness course (β = −0.193, p = .007) and passing a U.S. Communities course (β = −0.154, p = .021) were statistically significantly related to improved CoBRAS scores. Results of a matched pair design model revealed further evidence of an association between taking Global Awareness and U.S. Communities courses and CoBRAS scores.
Bilingual Hip Hop from Community to Classroom and Back: A Study in Decolonial Applied Ethnomusicology
Authors: Przybylski Liz
Published: September 2018

Education research often examines popular music as a tool for achieving classroom learning outcomes. Approaching pedagogical uses of music through applied ethnomusicology reveals even more useful conclusions about the social context and pedagogical applications of bilingual popular music. Research with musicians and teachers in Minnesota and Manitoba indicates that Anishinaabemowin/English popular music encourages revernacularization by extending language use and cultural knowledge beyond the classroom. Rather than working solely through the English language, this educational approach strategically uses bilingual hip hop music in Indigenous languages and offers opportunities for students to form their own critical decolonial consciousness.
The Blind Eye Within: Jacqueline de Romilly on Seeing and Aging
Authors: Parca Maryline G.
Published: September 2018

Jacqueline de Romilly (1913–2010), one of the preeminent figures of classical philology in France during the 20th century, is best known for her books on 5th-century Athenian political and cultural history. She may also be remembered as the second woman (after Marguerite Yourcenar) to have been elected to the Académie française (1988) as one of its “Immortals.” Less familiar to her readers are the biographical works she wrote late in life, among them Les roses de la solitude (2006), Les revelations de la mémoire (2009), and Jeanne (2011). These provide a window on her joys and on her regrets at having lived her life as a classicist.

In Les roses de la solitude in particular, de Romilly, nearly blind and confined in the study and sitting room of the Paris apartment where she lived most of her adult life, gazes into her past, arrested by the sight of objects which have long figured in her daily life. Her heightened sense of mortality and near blindness focus the recollection of her past, personal and professional, around those objects and prompt reflections on a life both nourished and diminished by an uncompromising commitment to the classics.
The Future of SeaWorld
Authors: Javanaud Katie , Sanghani Harshmeena , Young Grace C.
Published: September 2018

When SeaWorld was founded in 1959, the effects of captivity on cetaceans were not well understood. The 2013 release of Blackfish, however, brought modern research and ethics into public light. While some animal activists may rejoice in there being no future for SeaWorld, we argue that SeaWorld has an opportunity to reform itself and the greater “animal entertainment” industry by replacing captive animal shows with virtual and artificial reality. SeaWorld has already stopped breeding orcas and has committed to ending orca shows. We argue it should now also commit to the end of other captive animal (e.g., seal) shows and we believe the proposed technological shifts could make this feasible.
The Case for Ethical Fur: Is In Vitro Fur a Viable Alternative?
Authors: Gambrell Rivers , Javanaud Katie , Sanghani Harshmeena
Published: September 2018

It is currently estimated that more than 1 billion animals are killed for the fur industry every year. This industry is estimated to be valued in the region of $40 billion. This indicates both that there is a moral imperative and an economic opportunity to explore alternatives to conventional fur. While faux fur is currently available on the market, its production is associated with environmentally destructive practices. The development of stem cell technologies provides an exciting new avenue to explore. Specifically, the use of induced pluripotent stem cells may provide a means of growing fur in a laboratory setting. Here we outline the proposed technology and methods. We consider and respond to a number of potential moral objections against pursuing this innovative possibility, arguing that the benefits such technology could bring to animals in the fur industry are too great to be ignored.
Cat Wars: The Devastating Consequences of a Dangerous Book
Authors: Schaffner Joan E.
Published: September 2018

Cat Wars is a dangerous book that declares war on all free-roaming cats. Filled with hyperbole and exaggerated statistics, the book argues that cats are a danger to humans, birds, and other free-living animals and should be eradicated from the landscape—a devastating, expensive, inhumane, and useless result. This review exposes the flaws in the authors’ analysis and ethical approach and redirects the dialogue toward an ethic that protects all animals. Compassionate conservationism promotes the use of nonlethal management strategies to protect individual birds and other animals while compassionately reducing the number of free-roaming cats.
Transpersonal caring model in home-Care nursing for children with special care needs
Authors: Tonin Luana , Lacerda Maria R. , Favero Luciane , Nascimento Jaqueline D. , Rocha Patricia K. , Girardon-Perlini Nara M.O.
Published: September 2018

The study was theoretically and philosophically guided by the Theory of Human Care, entailing the use of the Elements of the Clinical Caritas Process, having humanistic assumptions based on Home Care, and being operationalized by the following action steps: Initial Contact, Approaching, Transpersonal Encounter and Separation. It aimed to apply the Transpersonal Care Model in Home Care Nursing to children with special healthcare needs. Qualitative care-research (intervention), developed by means of five components: approaching the studied object; encounter with the cared-researched being; connections between theory and practice; separation from the researcher-caregiver being to the cared-researched being, and analysis of what has been learned by means of the General Analytical Strategy – Relying on theoretical propositions – and Specific Analytical Technique – Pattern Combination. The key results from the development of each one of the steps are, as follows: assumptions were applied 537 times, 322 usages of the Clinical Caritas Process, and 467 care needs were met by means of the model. The model potentialities were identified, understanding that it was built for the population at home care, thus enabling relation development, meeting their needs, and supporting nurses to foster care delivery.
DETERMINATION OF MECHANISMS OF WEAR FOR ROLLING-SLIDING CONTACT IN SELECTED OPERATIONAL CONDITIONS BY MEANS OF SURFACE TOPOGRAPHY AND MES STUDIES
Authors: BĄKOWSKI Henryk , ŁAZARZ Bogusław
Published: September 2018

The paper presents the influence of selected operating factors, i.e. load, slip, and wear rate, and surface
conditions. The wear mechanism between the cooperating rolling surfaces in the rolling/sliding combination
varies due to the interaction of the complex stresses / deformations caused by the variable operating conditions.
Surface roughness studies have allowed determining the stereological parameters that are specific to the set
type of wear. In addition, simulation studies using the Finite Element Method in a roll-to-roll system have
been used to determine the value and depth of maximum stresses and deformations occurring in the surface
layer due to the interaction of two co-operating bodies. Geometric models have the same properties and
disadvantages as the surface layer in a real object. Reflecting the operating conditions and defining the wear
mechanisms in the proposed research allowed us to determine the state of the surface layer and predict its
durability.
STUDY OF THE IMPACT OF INCREMENTAL TECHNOLOGY ON MECHANICAL AND TRIBOLOGICAL PROPERTIES OF BIOMATERIALS
Authors: BOJKO Łukasz , RYNIEWICZ Wojciech , RYNIEWICZ Anna M. , KOT Marcin
Published: September 2018

The latest method for creating denture replenishment in CAD / CAM systems is Direct Metal Laser Sintering
(DMLS) technology. With the use of DMLS, prosthodontics, implant prosthetics, and facial-cranialjaw
surgery adapted to individual patient conditions can be realized. The aim is to evaluate the strength,
microstructure, and tribological properties of Ti6Al4V and CoCrMo alloys obtained from DMLS technology
in the aspect of therapeutic constructions. The conducted tests show that, in the DMLS technology, as
compared to milling technology preceded by casting and forging or pressed powder and sintering, for the
same percentage composition of elements, the micromechanical properties, microstructural and tribological
change. This procedure, from which constructions for various dental applications are obtained, is the new
technology preferred for making permanent restorations faced with ceramics, producing intravascular
implants, and implants of the temporomandibular joint. It can be an alternative to conventional cast-based
methods and CAD / CAM based milling.
INFLUENCE OF THE IMPACT ANGLE OF A SOLID PARTICLE JET ON THE EROSION WEAR OF 38GSA AND HARDOX 500 STEEL
Authors: KRUPICZ Bazyli , TARASIUK Wojciech , NAPIÓRKOWSKI Jerzy , LIGIER Krzysztof
Published: September 2018

The paper investigated the influence of the impact angle of a solid particle jet on the erosion wear of 38GSA and Hardox 500 steel. The basis of the analysis was the assumption of the existence of a correlation between mechanical properties of the material, represented by the work of deformation (P) determined from the stressstrain diagram (U). The impact angle of quartz sand particles (30, 60, and 90 °) was considered through the separation of kinetic energy of particles impacting the eroded surface perpendicularly and tangentially.
MICROSCOPIC TRIBOLOGICAL ANALYSIS OF THE KNEE JOINT
Authors: RYNIEWICZ Anna M. , RYNIEWICZ Andrzej , PUKALUK Anna , PAŁKA Paweł
Published: September 2018

The aim of the conducted research was the evaluation of the topography and the structure of the superficial layer of meniscus and articular cartilage. These are surfaces that optimise the friction and lubrication process in the knee joint. The animal samples of the menisci and the articular cartilage were examined. The research was performed using scanning electron microscopes and an atomic force microscope. The structure of the surface of meniscus and articular cartilage is very regular. The collagenous fibres, which are embedded in the ground substance, are parallel to the surface. The undulation of the surface was observed. In the area of the anterior horn on tibia side of both menisci as well as in the anterior area of tibial plateau, the concavity and convexity pattern is evident. The observed cavities enable the accumulation of the synovial fluid. The synovial fluid plays the role of the lubricant in the knee joint, and its presence is highly desired during the load transmission.
COATINGS WITH ADVANCED MICROSTRUCTURE FOR BIOMEDICAL APPLICATIONS
Authors: KOT Marcin , MAJOR Łukasz , MAJOR Roman , LACKNER Jurgen , PONTIE Maureen
Published: September 2018

The paper presents the effect of the complex architecture of Cr/CrN+a-C:H coatings on their mechanical
and tribological properties. These advanced coatings were compared with CrN single coatings and Cr/CrN
multilayers. All of them were deposited by the magnetron sputtering technique. The conducted tests allowed
nanohardness, elasticity modulus, fracture toughness, and adhesion of coatings to steel substrates to be
determined. Tribological tests were carried out under dry friction and in the presence of phosphate-buffered
saline PBS and foetal bovine serum FBS. For all test conditions, the friction coefficient and the wear index of
the produced coatings were determined. The lowest wear and the lowest coefficient of friction are exhibited
by coatings with complex Cr/CrN+a-C:H architecture. Furthermore, they are also resistant to the highly
corrosive PBS environment.
A RECORDING METHOD OF THE WORKING SURFACE OF COUNTER SAMPLES DURING SLIDE MATING WITH PTFE-BASED COMPOSITES
Authors: OLEKSIAK Zbigniew , WIĄZANIA Grzegorz , KOT Marcin
Published: September 2018

Images of the disk working surface are recorded during its revolution in order to forecast linear wear of PTFE-based composites. Particle agglomerates (enlarged 80×) of the investigated composite deposited on the disk working surface during the slide mating are seen in those images. Those agglomerates are commonly called the transfer film. The investigation capacities of a special tribotester equipped with video-stroboscope as well as the ways of image recording in a ‘bright’ and ‘dark’ field are presented in the paper. Photographs and schemes of subassemblies of the tribotester are given. The selected images of geometrical features of the transfer film recorded during revolutions of the disk are included. It was shown that images obtained in the ‘dark’ field are easier to be processed and computer analysed compared to the images obtained in the ‘bright’ field. A conceptual approach to the application of the computer analysis results for forecasting the wear of the PTFE composites under testing is presented.
INTERACTIONS BETWEEN LUBRICANT AND STEEL SUBSTRATE – A CONCEPTUAL METHOD OF ANALYSIS
Authors: PAWELEC Ewa , NESKA Mirosław
Published: September 2018

The paper demonstrates the methods for the analysis of the interaction between lubricant and steel substrate and presents the obtained results. The samples to be tested were commercially available greases as well as greases developed for the purpose of this research, containing a known amount of adhesion additives. Due to the lack of normalized methods, the authors applied indirect methods based on the analysis of the peel resistance and the resistance to variable shearing rates. The obtained results reveal that there is a possibility to apply the proposed methods for the comparative assessment of interactions between the grease and steel substrate.
THE TRIBOLOGICAL CHARACTERISTICS OF Al-Si/GRAPHITE COMPOSITE
Authors: WALCZAK Mariusz , ZWIERZCHOWSKI Maciej , BIENIAŚ Jarosław , CABAN Jacek
Published: September 2018

The paper presents the results of tribological research on AlSi12CuNiMg/5.7 wt.% Gr aluminium composite material (containing graphite particles in the amount of 5.7% wt.%) and on its matrix. This composite is used as high-tech construction material in the automotive industry, particularly for pistons, cylinder liners, and slide bearings. The tribological properties of these materials can be significantly changed as a result of the introduction of graphite particles. Therefore, wear tests have been carried out using the ball-on-disc tribometer. Microstructure and wear resistance of the matrix and composite alloy have been subjected to comparative analysis. It was demonstrated that the composite reinforced with graphite is characterized by a lower friction coefficient and lower wear in comparison to the matrix.
ASSESSMENT OF TRIBOLOGICAL PROPERTIES OF POLYMERS USED IN ADDITIVE TECHNOLOGIES SLS AND PJM
Authors: KOZIOR Tomasz , KUNDERA Czesław
Published: September 2018

The paper presents preliminary results of tribological research on materials used in two additive technologies photo-curing polymer resin PJM and selective laser sintering of polyamide powders SLS. A Tribometer T-15 type ring-disk was used to determine the impact of technological parameters, e.g., printing direction and building layer thickness on the selected tribological properties and wear processes for elements generally used as machine parts.
MECHANICAL PROPERTIES OF MATERIALS AND THEIR EROSIVE WEAR
Authors: KRUPICZ Bazyli , LISZEWSKI Mariusz , TARASIUK Wojciech
Published: September 2018

In this paper, the authors analyse the impact of selected mechanical properties of materials on their erosive wear caused by a steady stream of solid particles. A wear process is a function of the material properties of two materials that interact with each other in a given environment, i.e. the construction material and the particles that cause erosion. Erosive losses occur upon reaching a critical condition of damaging an element of the material’s surface under the influence of kinetic energy that result from incident particles of an abrasive material. It is proposed that the critical condition that accompanies the formation of erosion losses should be represented by the toughness (U) and the specific work of the deformation of the sample in the tensile strength test (W). The study involved the following materials: NC6, 42CrMo4, 20MnCr5, and S235JR.
THE EFFECT OF THE IONIZING RADIATION ON THE TRIBOLOGICAL PROPERTIES OF THERMOPLASTIC POLYMERS RUBBING AGAINST STEEL
Authors: NIEMIEC Aneta , KUJAWA Maciej , WIELEBA Wojciech
Published: September 2018

The paper describes the effects of gamma radiation doses on the tribological and mechanical properties of selected thermoplastic polymers: PEEK, PEI, PET, and PA6. Samples of those polymers were irradiated with gamma rays of energy 1, 1.2, 3, 4, 5 MeV and with the intensity of the radiation beam 4, 7, 10, 30, 40 μA. With an increasing dose of radiation, properties such as microhardness, the friction coefficient of polymers, and the wear rate are changed. The chemical structure of the irradiated polymer may be changed by crosslinking but also by chain scission. The modified polymers may be used in medical science, electronics, and space technology. In this article, we report the results of steel C45 – thermoplastics (PEEK, PEI, PET, and PA6) friction couple during the slip motion. The analysis is focused on the friction coefficient, wear rate, and microhardness. Kinematic parameters of the experiment in slide movement were constant and defined by the following values: contact pressure p = 1MPa and sliding velocity v = 1m/s. The authors observed that, as gamma radiation dose increased, the microhardness and friction coefficient increased and their wear intensity decreased. Polymers change their microstructure and molecular structure when they are subjected to gamma ray irradiation, which results in modification on many important physical and chemical properties.
THE CHANGE OF FRICTION AND LOAD- CARRYING CAPACITY OF THE JOURNAL BEARING WITH THE CONSIDERATION OF THE OIL AGEING
Authors: SIKORA Grzegorz , MISZCZAK Andrzej
Published: September 2018

This paper presents numerical calculations of the hydrodynamic pressure distribution, carrying capacity, and friction coefficient in the gap of a journal bearing. The analysed bearing is lubricated using motor oil. In this paper, oil ageing and temperature influence on viscosity are taken into account. Viscosity changes in the pressure and shear rate are not considered. These changes will be considered in other papers. For the hydrodynamic lubrication analysis, laminar flow of the lubrication fluid and non-isothermal lubrication model of the journal bearing were assumed. As the constitutive equation, the classical, Newtonian model was used. This model was extended by the viscosity changes in temperature and exploitation time. For the considerations, the cylindrical journal bearing with the finite length and smooth bearing, with the full angle of wrap were taken.
COINCIDENCE OF THE TECHNOLOGY AND THE SURFACE TOPOGRAPHY OF SPHERICAL ELEMENTS OCCURING DURING MACHINING PROCESS OF HIGH PRECISION
Authors: NIEMCZEWSKA-WÓJCIK Magdalena
Published: September 2018

The paper presents issues concerning the surface layer and the changes in surface topography with respect to spherical elements at the subsequent stages of manufacturing process. Special attention was paid to the forming of surface topography in precision machining processes (preliminary grinding, precision grinding, lapping with polishing). The subjects of research and analysis were spherical elements made of a biomaterial, i.e. titanium alloy (Ti-6.5Al-1.3Si-2Zr). The surfaces of the studied components shaped during the subsequent operations of abrasive machining processes were measured using a coordinate measurement machine (CMM) and a white light interferometer (WLI). Based on the obtained results, the changes in the surface topography of metallic spherical elements brought about during the subsequent operations of precision machining processes were assessed. In addition to this, functional properties of these surfaces were identified.
ABRASIVE WEAR MECHANISMS OF ANTIWEAR COATINGS IN BALL-CRATERING TESTS
Authors: OSUCH-SŁOMKA Edyta
Published: September 2018

The article is a continuation of research on the mechanisms of wear on PVD coatings observed after tests had been performed with the use of the ball-cratering method evaluating the wear. The work conditions of friction point in which tribological tests had been performed were calculated based on the optimization experiments described in independent studies [L. 1–2]. The aim of the article is to analyse the boundary surface coating–substrate resulting from abrasive wear. The observed area is located on the border of the trace of wear in the shape of a crater, at the point of the exit of the ball from the trace in accordance with the direction of the selection of the coating. The tested surface was observed with the use of microscopic techniques: scanning electron microscope (SEM) and interferometric microscope (WLI). The authors attempted to present the repetitive nature of the mechanism of the wear of thin PVD coatings with the use of the ball-cratering method, including its influences on receiving repeated traces of wear, which, in turn, has an influence on the determination of a reproducible value of the wear rate Kc, which is the factor determining the resistance of the tested coating to abrasive wear.
THE INFLUENCE OF THE EXTERNAL SURFACE TOPOGRAPHY OF GRANULAR PLANT MATERIALS ON EXTERNAL FRICTION
Authors: WÓJCIK Artur , FRĄCZEK Jarosław
Published: September 2018

The results of studies on external friction concerning granular plant materials that include, among others, grains, seeds of various plants, and powdered plant material, have been applied to the design of machines and devices for transport, sorting, cleaning, and blending. A separate and equally important matter is the storage of these materials in silos. The article presents the influence the surface topography of selected granular materials has upon the force of external friction. The research was performed with a specially designed adapter attached to the testing machine MTS, which is used to determine the external friction force of granular materials rubbing against various surfaces in a function of displacement. To define the topography of the external surface, a 3D scanner and specialized software were used. The authors have attempted to develop a model of friction taking into account the topography of the surface.
STRUCTURE AND PROPERTIES OF MULTI COMPONENT (Ti-Zr-Cr-Nb)N COATINGS OBTAINED BY VACUUM-ARC DEPOSITION
Authors: YESKERMESSOV Didar K. , PLOTNIKOV Sergey V. , YERDYBAEVA Nazgul K.
Published: September 2018

Investigated multicomponent coating nitride (Ti-Zr-Cr-Nb)N in this study were obtained using a well-developed technique of vacuum-arc deposition. Theoretical and experimental studies show that the chemical composition, microstructure, and mechanical properties of coatings are based closely on deposition parameters (the working gas pressure and bias potential on the substrate). The microstructure and mechanical properties (Ti-Zr-Cr-Nb)N coatings were investigated using a scanning electron microscope (SEM) equipped with energy dispersive microanalysis prefix and X-ray diffraction (XRD). Phase analysis of nitride coatings (Zr-Ti-Cr-Nb)N indicates a TiN phase, NbTiN2, ZrTiNb, ZrNb, TiCr and α-Ti. The coatings thickness reached 6.8 μm and their maximum of hardness was H = 43,7GPa. Tribological (test “ball-on-disc”) and mechanical (scratch test) properties of multi-coating were studied. The experimental results obtained by studying multicomponent coatings (Ti-Zr-Cr-Nb)N are promising and can be used as protective coatings for cutting tools and structural materials.
Correlation of Fine Needle Aspiration Cytology of Thyroid Gland with Histopathological Results
Authors: Machała Ewa , Sopiński Jan , Iavorska Iulia , Kołomecki Krzysztof
Published: September 2018

ABSTRACT
Fine needle aspiration cytology (FNAC) is considered as the gold standard diagnostic test for the diagnosis of thyroid nodules. It is a cost-effective procedure that provides specific diagnosis rapidly with minimal complications. It plays an important role in the determination of treatment- patients with suspected malignancy diagnosis can be subjected to surgery. On the other hand it can decrease the rate of unnecessary surgeries.
Aims: The aim of this study was to evaluate and compare the correlation, accuracy of fine needle aspirational cytology (FNAC) in the diagnosis of thyroid lesions with the final histopathologic diagnosis in the surgical specimens.
Materials and Methods: In our study we have performed a retrospective analysis of a case series of patients who were admitted to the Department of Endocrine, General and Oncological Surgery of Hospital of M. Kopernik in Łodź (Poland) between May 2016 and December 2017 and underwent FNAC with subsequent surgery. Cytological diagnosis was classified into six Bethesda categories.
Results: On cytological examination 1070/1262 were reported as benign, 49 malignant and 143 suspicious. On histopathological examination, 956/1070 cases were confirmed as benign but there were 114 discordant cases. Among the other cases histopathology diagnosis of malignancy matched in 45/49 and 128/143 cases.The sensitivity and specificity were 60,28% and 98,05% respectively. False positive rate was 1.95% and false negative rate was 39.72%. The positive predictive value was 90.1% and negative predictive value was 89.35%. Accuracy of FNA in differentiating benign from malignant thyroid lesions was 89,46%.
Conclusions: Fine needle aspiration cytology is a simple, cost-effective and popular procedure for the diagnosis of thyroid cancer. It is recommended as the first line investigation for the diagnosis of thyroid lessions.