bluuebunny/crossref_metadata_2025 huggingface dataset:
Le partenariat entre les entreprises classiques et les entreprises de l’Économie Sociale et Solidaire : générateur de soft skills ?
Authors: Tessier Nathalie
Published: April 2021

Les partenariats entre les entreprises classiques et celles du secteur de l’Économie Sociale et Solidaire permettent de créer de nouvelles opportunités pour le développement économique territorial et les innovations sociales. Plus particulièrement dans le domaine managérial, cette alliance peut s’avérer particulièrement bénéfique pour le développement des soft skills chez les collaborateurs engagés dans ces projets. Cet article vise dans un premier temps à expliquer les partenariats entre les entreprises classiques et les entreprises du secteur de l’Économie Sociale et Solidaire, et la notion de soft skills . Dans un deuxième temps, nous présentons le cadre méthodologique de notre enquête appelée « Part’Innov », projet financé par l’Europe. Nos résultats témoignent de l’émergence de soft skills dans les situations de partenariats tant du côté des acteurs engagés dans les entreprises classiques que ceux des structures de l’ESS. Nous terminons en proposant quelques pistes d’actions.
Parole et violence, langage et civilisation
Authors: Metton Agnès
Published: April 2021

Après la distinction des niveaux du langage et de la parole, l’abord de la violence clinique permet de distinguer offre analytique et psychothérapies. Les paradoxes de la répression sociale de la violence et du surmoi impératif de jouissance renvoient à la dissidence pulsionnelle, et font interroger les liens de l’individuel et du collectif. L’usage de la parole et le pouvoir du langage sont questionnés par quelques exemples.
La garçonne et l’assassin : désir féminin et pousse-à-la-femme
Authors: Mosconi Muriel
Published: April 2021

Comment le désir d’une femme intervient-il dans le pousse-à-la-femme de son compagnon ? L’histoire de Louise Grappe et de Paul Grappe, déserteur travesti, dans le Paris des années folles relatée dans La Garçonne et l’assassin de Fabrice Virgili et Danièle Voldman et les deux fictions qui en sont tirées, la bande dessinée Mauvais genre de Chloé Cruchaudet et le film Nos années folles de André Téchiné, nous permettrons d’aborder cette question.
VIOLENCE ! Vous avez dit violence ?
Authors: Castelbou Branaa Anne , Rollet Nathalie
Published: April 2021

À propos des effets d’un dispositif d’offre de paroles pour traiter les faits transgressifs violents commis par de jeunes adolescents placés en institution spécialisée. Ce dispositif clinique institutionnel, orienté par l’éthique du discours analytique, se propose de mobiliser l’acte de dire en responsabilisant le sujet au-delà de la sanction donnée.
Ray-tracing Calculation Using Scheimpflug Tomography of Diffractive Extended Depth of Focus IOLs Following Myopic LASIK
Authors: Lwowski Christoph , Van Keer Karel , Adas Mahmoud , Schwarz Luisa , Hinzelmann Lisa , Pawlowicz Katarzyna , Kohnen Thomas
Published: April 2021

PURPOSE:

To evaluate a ray-tracing formula for intraocular lens (IOL) calculation of diffractive extended depth of focus IOLs after myopic laser in situ keratomileusis (LASIK) compared to formulas from an established online calculator.

METHODS:

This retrospective, consecutive case series included patients after cataract surgery with implantation of an extended depth of focus (EDOF) IOL (AT LARA, Carl Zeiss Meditec; Symfony, Johnson & Johnson) and a history of myopic LASIK. Preoperative assessments included biometry (IOLMaster; Carl Zeiss Meditec) and corneal tomography, including true net power (TNP) (Pentacam; Oculus Optikgeräte GmbH). To evaluate the measurements, the simulated keratometry values (SimK) were compared to the TNP. Regarding IOL calculation, the mean prediction error, mean and median absolute prediction error (MAE and MedAE), and number of eyes within ±0.50, ±1.00, and ±2.00 diopters (D) from the Haigis-L, Shammas, and Barrett True K No History formulas to the Potvin-Hill and Haigis with TNP (Pentacam) formulas were compared.

RESULTS:

Thirty-six eyes matched the inclusion criteria with a mean spherical equivalent of −6.26 ± 3.25 diopters (D) preoperatively and −0.79 ± 0.75 D postoperatively. The mean difference from SimK and TNP was significantly different from zero (
P
< .001; −1.24 ± 0.81 D). The best performing formulas by MedAE were the Potvin-Hill and Barrett True K No History (0.39 ± 0.78 and 0.64 ± 1.00 D). The formula with the most eyes within ±0.50 D was the Potvin-Hill (64%), followed by the Barrett True K No History (44%). For MAE and percentage of eyes within ±0.50 D, the Potvin-Hill formula was significantly better than the Haigis-L, Shammas, and Haigis-TNP formulas (
P
< .05).

CONCLUSIONS:

Calculation of IOLs in patients who had LASIK remains less predicable than calculations for virgin eyes. Using ray-tracing to calculate diffractive EDOF IOLs after myopic LASIK, the Potvin-Hill formula outperformed established formulas in terms of the percentage within target refraction and the MAE.

[
J Refract Surg.
2021;37(4):231–239.]
Coma Influence on Manifest Astigmatism in Coma-Dominant Irregular Corneal Optics
Authors: Zhou Wen , Stojanovic Filip , Reinstein Dan Z. , Archer Timothy J. , Chen Xiangjun , Feng Yue , Stojanovic Aleksandar
Published: April 2021

PURPOSE:

To evaluate the influence of coma on manifest refractive cylinder (MRC) in eyes with coma-dominated corneal optics and suggest alternative guidelines for surgical planning of astigmatism correction in topography-guided ablation and toric intraocular lens (IOL) exchange surgery.

METHODS:

Twelve eyes with coma-dominant corneal optics and low lenticular astigmatism were selected. The astigmatism remaining after subtraction of total corneal astigmatism (TCA) and lenticular astigmatism from MRC, termed discrepant astigmatism, was calculated and correlated to corneal coma at the anterior surface. Refractive and topography data were then used to simulate topography-guided refractive surgery (topography-guided group) in 7 eyes and lenticular exchange surgery with toric intraocular lens (IOL) implantation (toric IOL group) in 5 eyes. The estimated postoperative MRC after correction of TCA or MRC for each group was compared.

RESULTS:

The axis and amplitude of discrepant astigmatism correlated strongly with the axis and amplitude of coma. In the topography-guided group, where topography-guided ablation eliminated corneal higher order aberrations (HOAs), TCA-based correction led to less estimated postoperative manifest astigmatism than MRC-based correction. In the toric IOL group, where removal of the crystalline lens did not affect corneal HOAs, MRC-based correction via toric IOL implantation led to less estimated postoperative astigmatism than TCA-based correction.

CONCLUSIONS:

Discrepant astigmatism in eyes with coma-dominant corneal optics correlates with coma. In such eyes, treating TCA, along with corneal HOAs, instead of MRC, seems appropriate in topography-guided treatments, whereas treating MRC may be a better choice in lenticular exchange surgery with toric IOL implantation, where corneal HOAs are not treated.

[
J Refract Surg
. 2021;37(4):274–282.]
The Origins and Evolution of Emergency Medical Services for Children
Authors: Fuchs Susan
Published: April 2021

The emergency medical services for children (EMSC) program was established in 1984 to improve the quality of emergency care for children. Since that time, all 50 states and Washington, DC, 5 US territories, and 3 freely associated states have received federal funding to achieve this goal. There have been many unique training and education programs developed, along with quality improvement and pediatric research initiatives. This article provides a history of the EMSC program and its accomplishments.

[
Pediatr Ann
. 2021;50(4):e150–e154.]
Pediatric Emergency Department Challenges and Response to COVID-19
Authors: Jain Shobhit , Fahlgren Rebecca , Giovanni Joan , Dowd M. Denise
Published: April 2021

Severe acute respiratory syndrome coronavirus 2, the virus causing the pandemic illness coronavirus disease 2019, was first detected in the United States in January 2020. As the illness spread across the country, all aspects and venues of health care were significantly impacted. This article explores the challenges and response of one children's emergency medicine division related to surge planning, personal protective equipment, screening, testing, staffing, and other operational challenges, and describes the impact and implications thus far.

[
Pediatr Ann.
2021;50(4):e172–e177.]
Thyroid Disease in Children and Adolescents
Authors: Khan Leah
Published: April 2021

The thyroid plays a major role in growth and development, and the hormones it produces can affect many different systems of the body. For this reason, the thyroid should always be at the front of our minds when evaluating children and adolescents. The symptoms of thyroid abnormalities can often be subtle and evolve over time, so we must have a high index of suspicion when providing care for our patients. It is important to understand what can go wrong with the thyroid, how to diagnose thyroid disease, and how to manage thyroid abnormalities. Whether it is structural changes in the thyroid such as goiter or nodules, functional changes that lead to hyperthyroidism or hypothyroidism, or thyroid cancer, a thorough examination and appropriate treatment is essential to maintain optimal cognitive and physical growth throughout childhood and adolescence. This article will discuss the most common thyroid abnormalities, how to diagnose them, and how to treat and manage them in both the short and long term.

[
Pediatr Ann
. 2021;50(4):e143–e147.

]
Las monteas y trazados de arquitectura del claustro bajo del monasterio de San Millán de la Cogolla, de Yuso (La Rioja, España), su registro, preservación y difusión
Authors: Arrúe Ugarte Begoña , Valle Melón José Manuel , Rodríguez Miranda Álvaro , Elorriaga Aguirre Garbiñe
Published: April 2021

La existencia de un rico conjunto de monteas y trazados de arquitectura en el claustro bajo del monasterio de San Millán de la Cogolla, de Yuso, ha hecho necesario el desarrollo y la aplicación de una metodología que posibilite el registro, preservación y difusión, de modo abierto, de la información que atesoran sus muros. La documentación parte del calco directo de los trazos y la posterior digitalización y sobreimposición del dibujo sobre el modelo tridimensional fotogramétrico. Por su parte, la preservación y difusión en formato digital se establece a través de un repositorio institucional que se encuentra enlazado a través de Europeana. Los plásticos originales con los calcos directos han sido depositados en el archivo del monasterio. Asimismo, se ha desarrollado una aplicación de realidad aumentada que permite la recreación virtual de los trazos sobre los alzados del claustro de manera interactiva.
Blood Lead Declines in Wintering American Black Ducks in New Jersey Following the Lead Shot Ban
Authors: Lewis Nicole L. , Nichols Theodore C. , Lilley Christina , Roscoe Douglas E. , Lovy Jan
Published: April 2021

Waterfowl managers first recognized the problem of lead poisoning in ducks from the ingestion of spent lead shot (pellets) over 100 years ago. The phaseout of lead shot for waterfowl hunting began in the Atlantic Flyway in the 1970s. Lead shot was subsequently banned throughout the United States and Canada prior to 2000. We compared blood lead levels in American black ducks Anas rubripes wintering in coastal New Jersey in 1978, prior to the lead ban, and in 2017, about 39 years after lead shot was first banned for use in Atlantic coastal marshes and 27 years after it was banned for waterfowl hunting in New Jersey. The prevalence of blood lead >0.2 ppm, a level commonly used to indicate lead exposure, declined nearly fourfold from 1978 (79%) to 2017 (20%). We found no significant differences in the prevalence of birds with blood lead levels >0.2 ppm between sexes in either year or between age classes in 2017. The prevalence of ducks with blood lead levels >1.0 ppm, considered clinically evident toxicity, declined from 19% in 1978 to 1% in 2017. Our study provides further evidence that the ban on the use of lead shot over 20 years ago throughout North America has resulted in lower blood lead levels in waterfowl. Notwithstanding, we still found evidence of lead exposure in black ducks in 2017, which warrants further investigation.
Remote Ecological Monitoring with Smartphones and Tasker
Authors: Donovan Therese , Balantic Cathleen , Katz Jonathan , Massar Mark , Knutson Randy , Duh Kara , Jones Peter , Epstein Keith , Lacasse-Roger Julien , Dias João
Published: April 2021

Researchers have increasingly used autonomous monitoring units to record animal sounds, track phenology with timed photographs, and snap images when triggered by motion. We piloted the use of smartphones to monitor wildlife in the Riverside East Solar Energy Zone (California) and at Indiana Dunes National Park (Indiana). For both efforts, we established remote autonomous monitoring stations in which we housed an Android smartphone in a weather-proof box mounted to a pole and powered by solar panels. We connected each smartphone to a Google account, and the smartphone received its recording/photo schedule daily via a Google Calendar connection when in data transmission mode. Phones were automated by Tasker, an Android application for automating cell phone tasks. We describe a simple approach that could be adopted by others who wish to use nonproprietary methods of data collection and analysis.
La presse face aux élites politiques et économiques : le cas du Matin (1884-1944)
Authors: Pinsolle Dominique
Published: April 2021

Les journaux, dont le nombre croît fortement au cours du XIXe siècle, sont généralement vus comme un « Quatrième Pouvoir », ou un « contre-pouvoir ». Dans la mesure où ils informent la population, ils sont censés être un élément essentiel du système démocratique. Mais les liens entre la presse (qui est presque totalement libre en France après 1881) and les élites politiques et économiques sont ambigus. Le Matin, par exemple, un des quotidiens français les plus populaires durant la première moitié du XXe siècle, prétend toujours être le porte-parole du peuple contre les élites corrompues. Il organise ainsi de grands événements populaires ou de grandes campagnes retentissantes durant lesquels il attaque des élites politiques et économiques défaillantes au nom de la nation. Mais en réalité, ce journal est très proche de certains hommes d’affaires et de certains hommes politiques, tout en étant également lui-même corrompu à de nombreuses reprises.
Quantum gravity for dummies
Authors: Oldani Richard
Published: April 2021

Dirac noted in his first paper on quantum electrodynamics [Proc. Roy. Soc. A 114, 243 (1927)] that, “The theory is non-relativistic only on account of the time being counted throughout as a c-number [classically], instead of being treated symmetrically with the space coordinates.”
His suggestion for a relativistic theory of quantum mechanics is carried out here by describing the atom in configuration space as the action integral of a Lagrangian. Atomic structure is described with discrete coordinates in Minkowski space, while the atom itself resides in the curved space-time
continuum of the gravitational field, the background space of quantum gravity. Although it does not meet the more ambitious goals of a string theory or loop quantum gravity, it is the first successful theory. In other words, it is the first theory to describe how gravitational fields
interact with quanta at the microscopic level. This paper is dedicated to the thousands of theoretical physicists who have defended nonrelativistic theory since its inception in 1926 without questioning its limitations even as it lost touch with reality and became ever more difficult to believe.
Superheavy nuclei IX: 1300 ≤ A < 1400 systems
Authors: Bevelacqua J. J.
Published: April 2021

Binding energies of nuclei are calculated in the mass region 1300 ≤ A < 1400. The calculations are performed using the adjusted Rost interaction, which suggests that a new island of stability exists for Z = 382 and in neighboring
systems. Enhanced stability occurs in the      382 1344   <mml:mi
mathvariant="bold">X  962     system.
Explanation of the huge difference between vacuum energy and dark energy in the theory of the dynamic medium of reference
Authors: Pignard Olivier
Published: April 2021

The object of this article is to present the vacuum energy and the dark energy within the framework of the theory of the dynamic medium of reference and to explain the phenomenal difference between the two energies. The dynamic medium is made up of entities (called gravitons) whose
vectorial average of speed determines the speed of the flux of the medium at each point in space. It is shown that inside the horizon of black holes (defined by the Schwarzschild radius), the speed of flux is greater than the speed of light, which means that the gravitons themselves have a
higher speed to that of light. The quantum entanglement of two photons which propagate in two opposite directions is due to a connection made by gravitons. It is therefore proposed that the gravitons move at the speed    V
G  ≈    R  universe
 t  Planck       ≈ 2.4 × 1069 m/s, which makes it possible
to guarantee the entanglement of the two photons whatever their position in the Universe and the impossibility to measure the time taken by the influence of a photon to arrive at its twin photon because it is less than the Planck time t Planck. The expression of the vacuum
energy and that of the dark energy within the framework of the theory of the dynamic medium of reference is established. The two expressions E vacuum and E dark and the value of the speed of the most distant galaxies V galaxy make it possible
to calculate an approximate value of the speed of the gravitons    V   G   ≈
  V   galaxy        E
  vacuum       E   dark
      ≈ 2.8 × 1069 m/s. This value of the speed of the graviton is very close to that obtained by the quantum entanglement of two photons, which reinforces
the existence of nonmaterial entities going at these phenomenal speeds.
Adaptation of the rapid multiplication method: selecting stem cuttings based on their number of leaves for cassava seedling production
Authors: Schoffel André , Lopes Sidinei José , Koefender Jana , Lúcio Alessandro Dal'Col , Camera Juliane Nicolodi , Golle Diego Pascoal
Published: April 2021

A study was conducted during four growing seasons to investigate the rooting capacity and survival percentage of cassava seedlings from stem cuttings selected based on their number of leaves. The experimental design was a randomized block design with five replications in a factorial scheme (4 × 2 × 2), totalling 16 treatments. Treatments consisted of combinations of growing season (September 22, October 7 and 19, and November 25), stem cuttings smaller (15 to 19.99 mm) and larger (20 to 25 mm) than 20 mm in diameter, and number of leaves on the stem cuttings (3 to 5 and 6 to 8 leaves). The experiment was carried out during the four growing seasons in a Van der Hoeven greenhouse. The greenhouse, as well as the benches on which the treatments were placed, had a north-south orientation. The greenhouse has an automatic mist irrigation system, and the mean temperature was 25 °C. The plant height at planting, number of leaves at planting, and number of leaves at 7 days after planting were measured. The final number of leaves, final plant height, shoot dry matter, root dry matter, and total dry matter were measured after acclimatization. Stem cuttings between 20 and 25 mm in diameter should be used to produce cassava seedlings with the rapid multiplication method. Cuttings with 6 to 8 visible leaves should be collected, and the cuttings should be planted at the end of September.
Temporal dynamics of soil susceptibility to erosion in semiarid watersheds
Authors: Silva Camilo Vinícius Trindade , Andrade Eunice Maia de , Lemos Filho Luis Cesar de Aquino , Ribeiro Filho Jacques Carvalho , Oliveira Júnior Hermínio Sabino de
Published: April 2021

The intensification of anthropogenic activities on soils contributes to soil loss through erosion. Moreover, the pattern of soil loss in the Cobra River watershed, located in the semiarid region of Rio Grande do Norte, is related to the history of land use and occupation, mainly from agriculture and the red ceramic industry, as well as the climatic seasonality of the region. Thus, the objective of this work was to identify the pattern of soil loss from the Cobra River microbasin in the state of Rio Grande do Norte. For this, the following analyses were performed: a survey of land use class areas for the years 1987, 1997, 2007 and 2017 as part of the Mapbiomas project; estimation of basin soil loss for these years; and quantification of areas of erosion vulnerability classes for this period. QGIS software was used to treat georeferenced data. According to the results, the land cover classes in the rich Cobra River microbasin fluctuated over time. Potential soil loss from the watershed increased from 1987 to 2017, with an increase of approximately 20 million megagrams of potentially erodible soil. The study of soil loss in a microbasin located in the Brazilian semiarid region should consider the variation in land cover over time, climatic seasonality and anthropic activity. To this end, it is important to use geotechnology and geoprocessing techniques to conduct a more robust spatiotemporal analysis.
Reduced ethylene synthesis of mangoes under high CO2 atmosphere storage
Authors: Bender Renar João , Brecht Jeffrey Karl , Sargent Steven Alonzo
Published: April 2021

. High CO2 atmospheres have been reported to be accountable for slower ripening processes of many fruit species. In modified or controlled atmosphere storage of mangoes (Mangifera indica L.) delayed ripening is attributed to the effects of CO2 on ethylene biosynthesis, which is reduced under CO2 concentrations beyond 10%. In the present work the objective was to determine if those elevated CO2 atmospheres on ethylene synthesis could be attributed to the action of CO2 upon ACC oxidase. Mature green or tree ripe `Tommy Atkins` mangoes were, in four experiments, held in a flow through system of either 10 or 25% CO2 mixed to 5% O2 or only air for 14 or 21 days at 5, 8 or 12°C. Mangoes in the 25% CO2 atmosphere did not produce detectable levels of ethylene, whereas under 10% CO2 the production rates were significantly suppressed at 5 or 8°C. However, 1-aminocyclopropane-1-carboxylic acid (ACC) concentrations in mango mesocarp tissue at retrieval from storage were similar to the air controls and ACC synthase activity was not completely inhibited. The direct effects of CO2 concentrations on ACC oxidase activity is to be considered the most important factor in inhibiting ethylene biosynthesis of mangoes under 25% CO2 atmospheres.
Volatile chemical composition of Piper sancti-felicis Trel essential oil and its biocidal action against Tribolium castaneum (Herbst)
Authors: Medrano-Ochoa José Luis , Palacio-Herrera Flor María , Torralbo-Cabrera Yuris , Arroyo-Salgado Bárbara , Jaramillo-Colorado Beatriz Eugenia , Pino-Benítez Nayive
Published: April 2021

This research assessed the fumigant activity of the essential oil from Piper sancti-felicis Trel and five of its components on the Tribolium castaneum (Herbst) biological model. Hydrodistillation was used for extraction of the essential oil, with separation and identification of the compounds through gas chromatography coupled to mass spectrometry (GC-MS). The fumigant was evaluated through gas dispersion on the T. castaneum. The majority compounds found in the EO were b-nerolidol (15.4%), 3-carene (14.9%), p-cymene (9.1%), spathulenol (8.2%), a-cubebene (6.2%) and calamenene (5.2%). Piper sancti-felicis displayed fumigant activity with a LC50 = 108.5 μg L-1 air, and other individual monoterpenes tested such as α-terpinolene (LC50 = 110.1 μg L-1 air), p-cymene (LC50 = 120.3 μg L-1 air), 3-carene (LC50 = 130.6 μg L-1 air), (R) -limonene (CL50 = 189.6 μg L-1 air), and a-pinene (LC50 = 213.1 μg L-1 air), were significantly less toxic than methyl pyrimiphos used as a positive control, CL50 = 87.4 μg L-1 air. The essential oil of P. sancti-felicis can be considered as a natural source of biocides
Semideciduous seasonal forest opiliofauna (Arachnida, Opiliones), State of Paraná, Brazil
Authors: Gomes Patrícia  Patrícia Pereira , Souza Alex Sandro Barros de , Silva Jean Victor Nery da , Ferreira Amanda da Silva , Almeida José Adolfo Mota de , Souza Marcos Magalhães de
Published: April 2021

Harvestmen are arachnids that play an important role in organic matter breakdown. However, there are many ecosystems in Brazil, including Conservation Units, which lack information about these organisms or are sub-sampled. Even in areas of Atlantic forest, a biome that hosts the greatest diversity and endemic rates of these arthropods in the world. In this perspective, the purpose of this study was to survey the harvestmen fauna in areas of Semideciduous Seasonal Forest in the Ilha Grande National Park, Paraná, southern Brazil, from February to November 2019, totaling 15 days and 60 hours, on six islands in the Paraná River. A total of 170 specimens was collected, distributed in five genera, comprising two species and three morphotypes. The low species richness may reflect the isolation of populations imposed by the island effect, however the study expanded the geographic distribution of Parapachyloides uncinatus and Discocyrtus invalidus, for which until then there was no record of occurrence in the Paraná State.
Vascular plants on inselberg landscapes in Espírito Santo state: bases for the creation of a protected area in southeastern Brazil
Authors: Covre João Mário Comper , Couto Dayvid Rodrigues , Dias Henrique Machado , Zorzanelli João Paulo Fernandes
Published: April 2021

Inselbergs are granitic or gneissic rocky outcrops prevalent in the landscape of southeastern Brazil. These ecosystems represent islands of isolated habitats that harbor a peculiar flora with high richness and endemism. The present study lists the species of vascular plants occurring in the Pedra da Andorinha Complex, located in the municipality of Jerônimo Monteiro/Cachoeiro de Itapemirim, southern Espírito Santo state, aiming to generate subsidies for the creation of a protected area. The survey was performed between July 2017 and October 2018, resulting in a record of 121 species, 96 genera, and 40 families. Bromeliaceae (17), Orchidaceae (12) and Fabaceae (10) were the richest families. The phytophysiognomy of exposed rock vegetation comprises a greater number of species (79 species) compared to the woody rupicolous communities (42). Eighteen of the collected species are threatened by extinction; a new species was discovered; and five were described based on materials previously collected in the studied location — Alcantarea patriae, Anthurium martinellii, Coleocephalocereus uebelmanniorum, Stigmatodon attenuatoides and Pitcairnia azouryi, the first four being endemic to the region. We also found Tabebuia reticulata, a rare species among Brazilian flora. Our results highlight the biological importance of the Pedra das Andorinhas Complex and reinforce the need to create a protected area to preserve biodiversity and the regional natural heritage.
The Way of Utilization of Fused Corundum Dust Waste for the High-Alumina Chamotte Production
Authors: Pavlova Irina A. , Getman Anna , Farafontova Elena P.
Published: April 2021

High-alumina chamotte with an Al2O3 content of more than 62% is a desirable raw material to produce high-alumina refractories. The production of high-alumina aggregate (chamotte) is carried out in various ways, using plastic or semi-dry technology for briquetting from commercial alumina and refractory clay. When grinding fused corundum, the dust containing 93–95% Al2O3 is formed; it is currently a substandard material. It is of interest to involve this waste product in the production of high-alumina chamotte. The developed technology allows obtaining the desirable material and utilizing production waste. In this project the briquetting parameters to produce high-alumina chamotte using corundum waste and refractory enriched kaolin were determined.
Numerical Modeling of the Anomalous Low-Temperature Dependence of the Tunneling Conductance of a "Dirty" N-I-N Junction
Authors: Kirpichenkova Natalia V. , Lozin Oleg I. , Kosach Anastasia A.
Published: April 2021

A numerical study of the low-temperature tunneling conductance G(T) of the “dirty” (low concentrations of the same non-magnetic impurities in the I layer) N-I-N junction (N is a normal metal; I is an insulator) with random quantum jumpers penetrating the disordered I-layer is performed. In a wide range of low impurity concentrations, the dependence G(T) anomalously, both qualitatively and quantitatively, differs from the corresponding dependence G0(T) in the “pure” (without impurities in the I layer) N-I-N junction. The numerical analysis of the dependence G(T) shows the possibility of the experimental manifestation of these anomalies.
New Types of Geo-Composite Materials for Anti-Filtration Systems
Authors: Vasilyev Sergey Mikhailovich , Kosichenko Yuri M. , Baev Oleg A.
Published: April 2021

The article discusses the results of studies of new types of geocomposite materials used for anti-filtration and drainage purposes in hydraulic engineering and environmental protection construction. As the main elements, the presented geocomposite materials include various types of synthetic materials – bentonite mats and profiled geomembrane. A distinctive feature of these materials is the inclusion of additional elements of geotextile material or polymer geomembrane in their design, these elements are connected to the main element by thermal bonding. As a result, the combined geocomposite materials acquire new properties: they become more waterproof and durable. At the same time, waterproof materials are used for anti-filtration systems (as screens and coverings for canals, ponds, dams and various types of waste collectors), and previous material are used for drainage systems (as drainage in hydraulic and civil engineering). New types of geocomposite materials have improved properties on water resistance and water permeability (filtration coefficient), durability and strength.
Technology of 3D Printing of Light Ceramics for Construction Products
Authors: Beregovoi Vitaly A. , Beregovoi A.M. , Lavrov I.Yu.
Published: April 2021

A 3D-printer for working with plastic mineral mixtures is developed, its kinematic scheme and principle of operation are described. The results of experiments on printing simple forms of plastic clay, using a piston-type extruder, are presented. In relation to an additive technology, a list of technological properties of mineral masses is defined The optimal amount of chemical additives has been established, which provides an increase in the uniformity of the raw material mass for printing products from light ceramics.
The Use of Overburden Clay in Ceramic Production
Authors: Pavlova Irina A. , Sapozhnikova Maria , Farafontova Elena P.
Published: April 2021

How the degree of grinding of clays with carbonate inclusions in the form of dolomite affects the quality of ceramic products, is examined. It is shown that unusable clay with large dolomite inclusions can be used in ceramic production after grinding particles to a size of less than 0.5 mm. It has been established that fine grinding of clay can eliminate the formation of “blowing” defect, while the frost resistance of ceramics increases. Clay unsuitable in the ceramic production can be used after fine processing to produce facing building bricks with a compressive strength above 15 MPa and frost resistance of more than 50 cycles, ceramic roof tiles with frost resistance of more than 100 cycles, majolica and water-proof pottery products.
Method of Metallurgical Production Waste Processing
Authors: Barakhtenko Vyacheslav
Published: April 2021

The modern development of the construction industry needs to find ways to create new competitive materials. Such materials are polymer composites, since the range of their application can be wide, due to the possibility of regulating their technical properties. This work presents a research on the development and production of polymer composites and products from them with the improved mechanical properties by adding finely dispersed techno-genic mineral raw materials as a functional filler. As a dispersed filler of the polyvinyl chloride composition, waste from the production of refined silicon was used, which is dust from the entrainment of furnaces captured by an electrostatic precipitator. To predict the characteristics of the materials obtained, the applicability criteria of techno-genic raw materials in the polyvinyl chloride composition are studied. Studies of the mechanical and operational properties of the obtained composites have confirmed the possibility of using techno-genic raw materials as functional fillers that affect the mechanics, durability, and also significantly reduce the cost of finished products.
Hardening Cement Conglomerates by Mining Industries Waste
Authors: Ilina Lilia V. , Mukhina Irina N. , Semenova Mariya M.
Published: April 2021

About 3.5 billion tons of mining waste is generated annually in Russia. The task of their utilization is urgent in connection with the accumulation of large-tonnage waste of simultaneously mined rocks, enrichment waste and crushing screenings. The problem can be solved by using these wastes as mineral additives to artificial cement-based conglomerates. According to the study results it was found, that the compressive strength of hardened cement paste increased during all hardening periods, when finely dispersed mining wastes were introduced. In the early stages of hardening, limestone had a predominant effect. Introduction of diopside led to the greatest hardening together with the hardening period increase. Linear and nonlinear mathematical models, describing the dependence of cement strength on the type and amount of mineral additives, were constructed. The highest strength values of hardened cement paste, both after hardening under normal conditions for 28 days, and after heat and moisture treatment could be achieved with 7% dispersed diopside. At the same time, the hardening effect (increase in the strength of cement by 35–40%) was retained when 1/3 of the diopside in the complex additive was replaced by dispersed limestone. An increase in the content of limestone in the complex additive composition over 1/3 was impractical.
Modeling of Grinding Technology Fibrous Materials in the Production Process
Authors: Valishina Z.T. , Kostochka A.V. , Saetshin A.A.
Published: April 2021

A comprehensive and systematic analysis of a large amount of experimental data was carried out, and, taking into account the available literature information, the mechanism of the process of grinding fibers of cellulose nitrate materials was revealed. The results obtained are of both scientific and practical interest, since the technological and rheological properties of the target products depend on the quality and nature of the grinding of fibrous materials. The combination of modern methods for studying the degree of dispersion, fractional composition, as well as the structure of fibrous materials during the grinding process, knowledge of the nature of the processing of fibers in various grinding units allow intensifying the grinding technology based on the created original technological scheme of the grinding process. The simulation of the grinding process of fibrous cellulose nitrate materials on the basis of experimental data, which allows predicting the properties of the target product and the creation of waste-free, resource-saving technology for producing materials with improved and adjustable characteristics, is carried out. The adequacy of the created model is shown.
Model and Results of a Study of the Synthesis of Finely Dispersed Silicon Carbide in an Electro-Thermal Reactor
Authors: Kuzevanov V.S. , Zakozhurnikov S.S. , Zakozhurnikova Galina S.
Published: April 2021

The high-temperature synthesis of silicon carbide (SiC) in an electro-thermal fluidized bed reactor (EFB) has advantages, in comparison with the production in resistance furnaces, in terms of specific energy consumption, productivity and the level of automation of the technological process. The basic equations of the fluidized-bed carbide formation process model are presented in the paper. The results of calculating the synthesis parameters of finely dispersed SiC in the stationary operation mode of the EFB reactor are also presented. The correspondence between the calculated and available experimental results on the output of the final product is shown.
Features of the Titanium Alloy Nanofibers Production for Neurosurgery and Ophthalmology
Authors: Shabashov Aleksey A.
Published: April 2021

A method for manufacturing the titanium alloy NT-50 nanofibers (1-20) microns in a composite assembly is proposed. The undamaged nanofibers production conditions are determined. Nanofibers are used to create new products: diagnostic sensors for ophthalmology.
Alumina Reinforced EP648 Metal Matrix Composite Produced by Selective Laser Melting Powder Bed Fusion Additive Technology
Authors: Lykov P.A. , Radionova L.V.
Published: April 2021

This paper is devoted to fabrication of alumina reinforced EP648 matrix composite material, using selective laser melting. of two-phase composite powder, prepared by ball milling of metal and ceramic powders. Five 10x10x5 mm bulk specimens were successfully manufactured using different process parameters. The obtained MMC specimens were characterized by scanning electron microscopy.
Research into the Effect of Speed Mismatch during Continuous Rolling on the Process Parameters
Authors: Nepryakhin Sergey O. , Vodopyanova Olga V.
Published: April 2021

The paper analyzes the influence of tension (dam) on the technological parameters of the rolling process (spreading, force and rolling torque). For the analysis, a model of continuous rolling in three adjacent stands was developed, using the Deform 3D software. The adequacy of the model was confirmed by comparing the experimental data from the small-section wire mill 150 and the simulation results. The error in determining the forming was 0.4%, and in determining the power parameters was 11%. Further, a computational experiment was planned, to identify the effect of mismatched of rolling speeds on technological parameters. According to the results of calculations, graphs of changes in technological parameters were constructed. It is established that, even small deviations of rolling speed from the matched mode lead to significant changes in technological parameters.
Contact Potential Difference as a Non-Destructive Testing of Steel
Authors: Aref'eva L.P. , Sukijazov A.G. , Dolgachev Yu.V.
Published: April 2021

For steels of different grades, the effect of the chemical composition, structure, and surface etching on the contact potential difference is studied using the Kelvin probe method. It was shown experimentally that, with a change in the structure and chemical composition, the contact potential difference changes. Etching the surface of the steel with a 4% solution of nitric acid leads to a sharp decrease in the magnitude of the contact potential difference, which allows us to conclude that the value of the electron work function from the sample surface increases. The ability to control the composition and structure of the material by the Kelvin probe method is shown.
Modeling Process of Semi-Continuous Extrusion of Hollow 6063 Aluminum Alloy Profiles Using QForm Extrusion
Authors: Koloskov Sergey , Sidelnikov Sergey , Voroshilov Denis
Published: April 2021

The results of modeling the process of semi-continuous extrusion of hollow profiles of aluminum alloy 6063 on horizontal hydraulic extruders are presented. By modeling with the help of the QForm Extrusion software package, the metal shaping and temperature conditions of this process were studied under given initial and boundary conditions. The authors investigated the various designs of sets of matrices and dividers and assessed the uneven velocity of the expiration of the elements of the profile and the temperature of the metal. Thanks to the gradual improvement of the design of the pressing tool, it was possible to achieve a uniform distribution of speeds and temperatures in the cross section of the profile. Industrial testing of the use of this tool for the manufacture of press products has shown that the proposed design methodology of using the QForm Extrusion software package can be successfully used to prepare the press production and can reduce the time required to master the technology of extruding aluminum alloy profiles.
Mechanism of Solid-State Amorphization in the Fe-Si-Cu-Mg-O System
Authors: Nikul'chenkov Nikolai N. , Redikul'tsev Andrey A. , Lobanov Mikhail L.
Published: April 2021

Solid-state amorphization process occurring at 600-1060 °C continuous annealing was observed by non-ambient x-ray diffraction on Fe-3%Si-0.5%Cu alloy surface with MgO as thermostable coating. The phenomenon was occurred at α→γ transformation temperatures (920-960 °C) in a layer consisting of Si solid solution in α-Fe and oxides (MgFe)2SiO4, (MgFe)O, SiO2. Amorphous state remained both during heating and cooling to 20 °C. Simulation for diffusion amorphization of Fe (Si) solid solution was proposed. Mg2Si complexes are reduced from oxides by hydrogen then transfer to solid solution and solid-state amorphization is occurred.
Development of New Composite Materials from Tetra Pak Packaging Waste
Authors: Kolyada Lyudmila G. , Smirnova A.V. , Tarasyuk Elena V.
Published: April 2021

Technological parameters of receiving composites from Tetra Pak packaging waste are determined in the work. Physical - mechanical characteristics of the received composites are defined. The analysis of the received results showed that composites from Tetra Pak packaging waste have loose structure and lower strength properties, in comparison with cardboard. Introduction of polyvinyl acetate (PVA) suspension leads to an increase in density of composites and strength properties. Tensile strength increases by 1,9 times, but doesn't reach the level of tensile strength of cardboard composites. Application of hot pressing results in formation of denser composite, thus, tensile strength of a sample increases by 2,8 times. Cumulative effect of PVA glue and hot pressing leads to an increase of composite tensile strength by 5,9 times. It becomes significantly higher than the similar characteristic for a packing cardboard. According to the realized complete factorial (CF), the adequate regression equation was received. It shows that the strength of Tetra Pak wastes composites, in a greater degree, depends on the concentration of PVA suspension.
Bending Steel Billet on Presses of Tube Electrical Welding Aggregation
Authors: Shinkin Vladimir N.
Published: April 2021

At the production of the steel thick-walled large-diameter pipes according to UOE-technology at the tube electrical welding aggregation 1020 (TEWA 1020), the steel sheet is in series bent on the flanging press, the pre-forming press and the final-forming press. When the steel sheet is deformed on the final-forming press, the excessively curved sections of the sheet are partially unbent in the opposite direction. The calculation of sheet’s curvature at the alternating bending causes the significant difficulties because of Bauschinger’s effect at bending, in which the mechanical characteristics of the steel change significantly. In this paper, the analytical method for calculating the final curvature of steel pipe billet at the alternating bend at UOE-technology is proposed. The results of the paper can be applied in metallurgy.
Formation of Structure and Properties of 30HGSN2A Steel at Technological Stages of Manufacture of Heavy-Loaded Parts
Authors: Muratov Vladimir S. , Yakimov Nikolay S.
Published: April 2021

The cases of premature failure of the barrel of liquid damper, made of complex alloyed high-strength 30HGSN2A steel, are analyzed. The options failure and the causes of their occurrence are established. Fatigue failure of the barrels during an operation is due to the failure of the chrome coating of the rod and the appearance of scorings on the surface of the barrel. Cases of failure of the barrels during official tests are associated with the reduced hardenability and an increased tendency to decarburize steel in the bottom of the barrel, due to the increased nitrogen content here (due to segregation). The influence treatment conditions on the structure and properties of steel are investigated. Modes of dehydration and final heat treatment of the products to eliminate their premature failures are recommended. The proposed conditions, in particular, include increasing the dehydration temperature to 200-230 oС, reducing the exposure time at the hardening temperature and reducing the tempering temperature, using vacuum heating.
Fracture of Electron Beam Welding Joints of Titan Alloys
Authors: Kostin Valery , Taranova Tetjana , Zvorykin Vladimir
Published: April 2021

Analysis of fracture surfaces morphology of material of welded joints of Ti-TiB system alloys and (α + β) Тi alloy, obtained by electron-beam welding under various technological modes, is carried out. Parameters alterable were the electron beam displacement velocity and initial temperature of the parts welded. Prevalent effect of boron phase on fracture character of Ti-TiB system alloys and possibility of ductility increase both Ti-TiB system and (α+β Тi alloy, due to thermal effect action, is shown.
Studying Aluminum Alloy Defects
Authors: Nemchinova Nina V. , Belskii Sergei S. , Vlasov Alexander A.
Published: April 2021

Aluminum is widely used in various industries in the form of alloys due to its unique properties - lightness, high electrical conductivity, and corrosion resistance. However, when casting alloys, various defects arise, the main of which are nonconformities of the ingot chemical composition, mechanical properties, and internal structure. The RUSAL Bratsk PJSC (, Irkutsk Region) aluminum alloy samples have been examined for pores, cracks, and oxide films. The causes of their occurrence have been analyzed and ways to eliminate these defects proposed. It has been found that, with increasing hydrogen content in the melt, micro-porosity leads to friability and macro-porosity of the alloy structure. According to the study results, the likelihood of cracks in the ingots could be reduced by evenly decreased metal temperature and casting velocity. The oxide film defects have been eliminated by feeding metal into the mold in a steady turbulence-free manner, increasing the metal settling time in a mixer, and reducing the alloy preparation time in a furnace.
Investigation of Temperature Deformations and Burning of Models from Polymers
Authors: Mamayeva Aksaule A. , Imbarova Akerke T. , Chukmanova Marzhan T.
Published: April 2021

The usage of 3D printing technology SLA and DLP is promising for obtaining casting models. The article presents the results of a study of temperature deformations, developing during the burning of models from polymers “Fun to Do Castable Blend”, “Oh-All! Red” and “Orange Fluor”. In the performance of the experiments, photopolymer models were exposed to an impact of isothermal at temperatures from 50 to 330 °C, and their linear dimensions measured; changes developing on their surface were noted. It is shown that, with an increase of the isothermal holding temperature, the models expand first and narrow later. It has been linked to temperature expansion and subsequent decomposition of the photopolymer. It is shown that the casting molds ,obtained with the usied thin-walled hollow casting models from these photopolymers, are destroyed at the stage of their burning.