bluuebunny/crossref_metadata_2025 huggingface dataset:
Resonances in a Coronal Loop Driven by Torsional Alfvén Waves Propagating from the Photosphere
Authors: Soler Roberto , Terradas Jaume , Oliver Ramón , Ballester José Luis
Published: March 2021

There is increasing evidence that magnetohydrodynamic waves play an important role in the propagation and dissipation of energy in the solar atmosphere. Here we investigate how torsional Alfvén waves driven at the photosphere can transport energy to an overlying coronal magnetic loop and explore their ability to heat the plasma. We consider a coronal loop whose feet are embedded in the partially ionized chromosphere. A broadband driver at the photosphere excites torsional Alfvén waves that propagate upward to the coronal loop. By means of numerical computations under the stationary-state assumption, we study the transmission of wave energy to the loop and the heating associated with ohmic diffusion and ion–neutral collisions. We find that wave transmission to the loop is heavily affected by the presence of cavity resonances when the frequency of the driver matches an eigenfrequency of the loop. A tremendous amount of wave energy is channeled to the coronal loop for those particular frequencies. The transmitted energy surpasses by many orders of magnitude the requirements to balance thermal radiation. However, dissipation is so weak in the coronal plasma that only a tiny percentage of the energy budget is converted into heat, which is not enough to compensate for radiative losses. Most of the energy simply leaks back to the chromosphere. Conversely, dissipation is much more efficient in the lower atmosphere, and wave heating can locally balance a significant fraction of radiation in the chromosphere. We argue that nonlinear effects such as turbulence triggered by the Kelvin–Helmholtz instability should enhance the heating efficiency at coronal heights.
Discovery of a New Redback Millisecond Pulsar Candidate: 4FGL J0940.3–7610
Authors: Swihart Samuel J. , Strader Jay , Aydi Elias , Chomiuk Laura , Dage Kristen C. , Shishkovsky Laura
Published: March 2021

We have discovered a new candidate redback millisecond pulsar binary near the center of the error ellipse of the bright unassociated Fermi-LAT γ-ray source 4FGL J0940.3–7610. The candidate counterpart is a variable optical source that also shows faint X-ray emission. Optical photometric and spectroscopic monitoring with the SOAR telescope indicates that the companion is a low-mass star in a 6.5 hr orbit around an invisible primary, showing both ellipsoidal variations and irradiation and consistent with the properties of known redback millisecond pulsar binaries. Given the orbital parameters, preliminary modeling of the optical light curves suggests an edge-on inclination and a low-mass (∼1.2–1.4 M
⊙) neutron star, along with a secondary mass somewhat more massive than the typical ≳0.4 M
⊙. This combination of inclination and secondary properties could make radio eclipses more likely for this system, explaining its previous nondiscovery in radio pulsation searches. Hence, 4FGL J0940.3–7610 may be a strong candidate for a focused search for γ-ray pulsations to enable the future detection of a millisecond pulsar.
A new granite cave-dwelling Bent-toed Gecko from Vietnam of the Cyrtodactylus irregularis group (Squamata; Gekkonidae) and a discussion on cave ecomorphology
Authors: Nguyen Anh The , Duong Tang Van , Grismer L. Lee , Poyarkov Nikolay A.
Published: March 2021

An integrative analysis of genetic, morphological, and ecological data recovered a new granite cave-adapted species, Cyrtodactylus raglaisp. nov., from the Song Giang River Valley, Khanh Hoa Province, Vietnam. Cyrtodactylus raglaisp. nov. is nested within one of two major clades within the irregularis species group where it forms a monophyletic group with C. cryptus and its sister species C. kingsadai. It differs from its sister species by an uncorrected pairwise sequence divergence of 16.5% and 16.8% based on the mitochondrial genes NADH dehydrogenase subunit 2 and its flanking tRNAs and the first subunit of cytochrome oxidase c (CO1), respectively. Cyrtodactylus raglaisp. nov. is a narrow-range endemic restricted to a riparian, granite cave microhabitat and its overall morphology bears that of other granite cave-dwelling ecomorphs in the genus. The Song Giang River Valley and its associated waterways are currently threatened by the construction of a hydropower station which will negatively impact the surrounding ecosystem. Urgent field surveys in this region are necessary in order to obtain critical data on its biodiversity and importance to conservation efforts in southern Vietnam.
On a general homogeneous three-dimensional system of difference equations
Authors: Touafek Nouressadat , Tollu Durhasan Turgut , Akrour Youssouf
Published: March 2021

In this work, we study the behavior of the solutions of following three-dimensional system of difference equations

   $ \begin{equation*} x_{n+1} = f(y_{n}, y_{n-1}), \, y_{n+1} = g(z_{n}, z_{n-1}), \, z_{n+1} = h(x_{n}, x_{n-1}) \end{equation*} $

where $ n\in \mathbb{N}_{0} $, the initial values $ x_{-1} $, $ x_{0} $, $ y_{-1} $, $ y_{0} $ $ z_{-1} $, $ z_{0} $ are positive real numbers, the functions $ f, \, g, \, h:\, \left(0, +\infty\right)^{2}\rightarrow\left(0, +\infty\right) $ are continuous and homogeneous of degree zero. By proving some general convergence theorems, we have established conditions for the global stability of the corresponding unique equilibrium point. We give necessary and sufficient conditions on existence of prime period two solutions of the above mentioned system. Also, we prove a result on oscillatory solutions. As applications of the obtained results, some particular systems of difference equations defined by homogeneous functions of degree zero are investigated. Our results generalize some existing ones in the literature.
Refined Wilf-equivalences by Comtet statistics
Authors: Fu Shishuo , Lin Zhicong , Wang Yaling
Published: March 2021

We launch a systematic study of the refined Wilf-equivalences by the statistics $ {\mathsf{comp}} $ and $ {\mathsf{iar}} $, where $ {\mathsf{comp}}(\pi) $ and $ {\mathsf{iar}}(\pi) $ are the number of components and the length of the initial ascending run of a permutation $ \pi $, respectively. As Comtet was the first one to consider the statistic $ {\mathsf{comp}} $ in his book Analyse combinatoire, any statistic equidistributed with $ {\mathsf{comp}} $ over a class of permutations is called by us a Comtet statistic over such class. This work is motivated by a triple equidistribution result of Rubey on $ 321 $-avoiding permutations, and a recent result of the first and third authors that $ {\mathsf{iar}} $ is a Comtet statistic over separable permutations. Some highlights of our results are:

● Bijective proofs of the symmetry of the joint distribution $ ({\mathsf{comp}}, {\mathsf{iar}}) $ over several Catalan and Schröder classes, preserving the values of the left-to-right maxima.

● A complete classification of $ {\mathsf{comp}} $- and $ {\mathsf{iar}} $-Wilf-equivalences for length $ 3 $ patterns and pairs of length $ 3 $ patterns. Calculations of the $ ({\mathsf{des}}, {\mathsf{iar}}, {\mathsf{comp}}) $ generating functions over these pattern avoiding classes and separable permutations.

● A further refinement of Wang's descent-double descent-Wilf equivalence between separable permutations and $ (2413, 4213) $-avoiding permutations by the Comtet statistic $ {\mathsf{iar}} $.
Structure of sympathetic Lie superalgebras
Authors: Fan Yusi , Yao Chenrui , Chen Liangyun
Published: March 2021

Sympathetic Lie superalgebras are defined and some classical properties of sympathetic Lie superalgebras are given. Among the main results, we prove that any Lie superalgebra $ L $ contains a maximal sympathetic graded ideal and we obtain some properties about sympathetic decomposition. More specifically, we study a general sympathetic Lie superalgebra $ L $ with graded ideals $ I $, $ J $ and $ S $ such that $ L = I\oplus J $ and $ L/S $ is a sympathetic Lie superalgebra, and we obtain some properties of $ L/S $. Furthermore, under certain assumptions on $ L $ we prove that the derivation algebra $ \mathrm{Der}(L) $ is sympathetic and that if in addition $ L $ is indecomposable, then $ \mathrm{Der}(L) $ is simply sympathetic.
Approximation of an optimal control problem for the time-fractional Fokker-Planck equation
Authors: Camilli Fabio , Duisembay Serikbolsyn , Tang Qing
Published: March 2021

In this paper, we study the numerical approximation of a system of PDEs which arises from an optimal control problem for the time-fractional Fokker-Planck equation with time-dependent drift. The system is composed of a backward time-fractional Hamilton-Jacobi-Bellman equation and a forward time-fractional Fokker-Planck equation. We approximate Caputo derivatives in the system by means of L1 schemes and the Hamiltonian by finite differences. The scheme for the Fokker-Planck equation is constructed in such a way that the duality structure of the PDE system is preserved on the discrete level. We prove the well-posedness of the scheme and the convergence to the solution of the continuous problem.
Species effect on decay resistance of wood exposed to exterior conditions above the ground in Spain
Authors: Conde-García M. , Conde-García M , Fernández-Golfín J.I.
Published: March 2021

The objective of this study is to evaluate the effect of the species on the biological resistance of wood against decay and to propose corrective values of the critical dose. To evaluate the species effect, the evolution of the number of days per year with moisture content exceeding 18% was assessed in flat sawn 20x100x750 mm3 test samples of Laricio, Scots and Radiata pines and also of Norway spruce, Eucalypt (globulus) and sweet chestnut during the years 2016, 2017 and 2018, exposed at seven locations in Spain with the most representative Spanish climates. A value of 1.0 is proposed for the four conifers, 2.51 for the Eucalypt and 1.84 for the Sweet chestnut. As regards the species effect it was not possible to separate that corresponding to the different wetting/releasing ability of each species and that of their crack susceptibility, both aspects having to be evaluated together as “species factor”.
Certifying lecturers’ English language skills for teaching in English-medium instruction programs in higher education
Authors: Dimova Slobodanka
Published: March 2021

L’enseignement des spécialités en anglais est de plus en plus souvent mis en place dans les universités traditionnellement non anglophones dans le cadre des politiques d’internationalisation des universités. L’augmentation du nombre de ces programmes soulève des inquiétudes quant à la qualité de l’enseignement si bien que de nombreuses universités ont commencé à mettre en place des certifications en anglais pour les professeurs non anglophones qui dispensent des enseignements en anglais. Les politiques de certification des enseignants varient selon les établissements d’enseignement supérieur. Certains établissements certifient les enseignants par le biais de formations spécifiques, par le biais de prestataires externes ou en interne, laquelle formation conduit à l’obtention d’un certificat. Les tests oraux et écrits conçus localement se fondent souvent sur l’échelle du CECR, car elle permet une reconnaissance internationale des résultats des tests. En s’appuyant sur la recherche et l’expérience d’un test institutionnel pour la compétence orale en anglais du personnel universitaire, cet article examine les avantages et les inconvénients des différents modèles de certification pour les enseignants et fournit des recommandations pour concevoir des pratiques de certification équitables et durables.
Bosquet des malades - Admiration des œuvres de Dieu
Authors: Carthagène Thérèse de
Published: March 2021

Cet ouvrage présente la première traduction critique en français des deux traités composés par Thérèse de Carthagène à la fin du XVe siècle, le Bosquet des malades et l’Admiration des œuvres de Dieu. Ce sont les plus anciens textes conservés écrits en vernaculaire castillan par une main féminine. Leur contenu frappe par son originalité : le premier est un traité consolatoire dans lequel l’auteure, devenue sourde, valorise la maladie et le handicap ; le second, une œuvre de polémique littéraire dans lequel elle défend son auteurité en tant que femme. Célèbres et bien étudiés depuis les années 1970 dans les sphères académiques hispanophone et anglophone, ils demeurent méconnus dans le monde francophone. Ils sont accompagnés par une introduction qui synthétise la bibliographie foisonnante et apporte quelques éléments de contexte supplémentaires issus de l’examen du seul manuscrit conservé.
Et si les stratégies d’apprentissage des étudiants et leurs perceptions envers l’évaluation des apprentissages avaient un lien avec l’ajustement académique dans un contexte de persévérance aux études universitaires?
Authors: Barbeau Nancy , Frenette Éric , Hébert Marie-Hélène
Published: March 2021

L'objectif de cette revue de littérature systématique consiste à vérifier les liens qui unissent les caractéristiques individuelles des étudiants (stratégies d’apprentissage, perceptions envers l’évaluation des apprentissages [attrait et croyances]) et l’ajustement académique dans un contexte de persévérance aux études universitaires. Sur la base de la démarche de revue de littérature systématique de Gough (2007), 21 articles scientifiques publiés entre 2006 et 2017 et présentant des études effectuées auprès d’étudiants en enseignement supérieur ont été retenus. Les résultats obtenus confirment l’existence de liens entre les stratégies d’apprentissage et les perceptions des étudiants envers l’évaluation, entre les stratégies et l’ajustement académique, mais aucun lien entre les perceptions des étudiants envers l’évaluation et l’ajustement académique. Il appert aussi une absence d’étude pouvant confirmer ou infirmer les liens entre les trois concepts.
Construction et mise en œuvre d’un doctorat international : des enjeux aux problèmes. Le cas des doctorats Erasmus Mundus
Authors: Hardouin Magali
Published: March 2021

L’article apporte une contribution à l’analyse des formations construites de manière conjointe entre des établissements d’enseignement supérieurs de pays différents par l’analyse du doctorat Erasmus Mundus (2009-2013). Ce programme visait, grâce à des cursus construits par des consortia d’établissements d'enseignement supérieur situés en Europe et dans le monde, à attirer de très bons doctorants des pays tiers dans l’Union européenne. Il cherchait à contrebalancer l'influence nord-américaine dans le domaine de la formation et de la recherche. Il illustre aussi la volonté de la Communauté Européenne (CE) de diffuser son modèle d’enseignement supérieur, jugé excellent, à travers le monde.À partir d’une méthodologie reposant sur une double approche (exploitation de bases de données, consolidée par des données recueillies au moyen de questionnaires et d’entretiens), l’article s’attacher à montrer que ce programme, proposé par la CE, à fortes connotations politiques et économiques, rencontre l’adhésion de nombreux acteurs qui en voient un intérêt indéniable. Cependant, force est aussi de constater que de nombreuses questions, fautes d’avoir été pensées et résolues en amont, au niveau européen, rendent bien difficile la structuration et la gestion de cette formation originale au niveau local et ne permettent pas finalement de répondre de manière satisfaisante aux objectifs prédéfinis.
Les représentations des étudiants de la formation BTS en Guadeloupe à l’épreuve des stages professionnels
Authors: Odacre Elisabeth , Issaieva Elisabeth , Delcroix Antoine
Published: March 2021

Notre étude porte sur le fonctionnement en Guadeloupe du Brevet de Technicien Supérieur (BTS), diplôme professionnel français se préparant en deux ans après le baccalauréat, dont les programmes et critères d’évaluation sont nationaux. Les lauréats sont supposés être immédiatement employables, en particulier dans leur environnement géographique local, ce qui peut conduire à des tensions faute d’adaptation possible des prescrits aux différents contextes. Le stage professionnel joue un rôle important dans ce diplôme. Nous étudions comment les représentations des étudiants de BTS évoluent, en relation avec la tension susmentionnée, avant et après le stage professionnel. Une enquête longitudinale par questionnaires a été menée auprès d’étudiants de BTS tourisme et assistant de manager. Les analyses montrent que les étudiants du BTS tourisme restent attachés au secteur d’activité visé, en se questionnant sur la possibilité de travailler en Guadeloupe alors qu’en BTS assistant de manager, une dégradation de la représentation du métier visé est constatée. Le stage conduit à une meilleure connaissance de la situation socioéconomique locale, ce qui modifie les représentations des étudiants.
Caracterização de Treinamentos de Habilidades Sociais em Grupo para Crianças: Revisão Integrativa da Literatura
Authors: Goulart Bittencourt Isabella , Menezes Marina
Published: March 2021

As habilidades sociais (HS) são classes de comportamentos que podem contribuir para a prevenção e redução de problemas de comportamento, bem como para a promoção do desenvolvimento socioemocional. O objetivo deste estudo foi caracterizar os treinamentos de HS em grupo de crianças para seis a 12 anos com desenvolvimento típico e atípico, em publicações nacionais e internacionais. Para isso, foi realizada uma revisão integrativa de literatura de publicações de 2009 a 2019, com descritores em português, inglês e espanhol, nas bases de dados SciELO, BVS, PsycInfo, SCOPUS e Web of Science. Foram selecionadas 29 publicações e os resultados indicaram o predomínio de estudos internacionais e com treinamentos para crianças com desenvolvimento típico, realizados por psicólogos, principalmente em contextos escolar e de saúde. Os temas trabalhados nas sessões não variaram em função de diagnósticos clínicos, entretanto a quantidade média de sessões foi maior em intervenções destinadas às crianças com desenvolvimento atípico. Constatou-se a influência do contexto nos programas de intervenção, embora os efeitos dos treinamentos tenham variado conforme o tamanho da amostra, duração, local de ocorrência, método para coletar as informações e medidas usadas para avaliar os resultados. Sugere-se que tais aspectos dos treinamentos sejam analisados considerando-se as variáveis em conjunto.
INFANTS’ CRYING SOUNDS AT PAIN STIMULI FROM INJECTIONS: ANALYSIS OF TIME–FREQUENCY DOMAIN AND CORRELATION WITH TEMPERAMENT DEVELOPMENT
Authors: Liao Shao-Chieh , Chen Pei-Yin , Lin Jiun-Hung , Chow Julie Chi , Chou Willy , Huang Yan-Jhen
Published: March 2021

Background: An infant is an individual who possesses his/her own innate personality. Crying is a form of communication, an expression of emotions and temperament. Our study aims to predict an infant’s temperament in the early stage by analyzing the crying sound after painful stimulation of vaccination. Methods: We analyze three types of information: (i) the crying sounds caused by the pain stimuli from being injected with a Hepatitis B vaccine, (ii) the answers provided by the parents in a temperament assessment scale (TAS) questionnaire, and (iii) backend analyses of the audio signals of the crying sounds. These data are subjected to correlation analyses, T-tests, and normal distribution for deriving the relationship between crying and temperament. Results: The results show that the manifestations of an infant’s temperament may be affected by the living environment and feeding habits. A tendency exists for a group of infants with similar and focused crying sounds to have higher average scores for three of nine temperament traits: approach or withdrawal, intensity of reaction, and quality of mood. Conclusions: An infant’s crying sounds in response to a pain stimulus can be used to predict his/her temperament in terms of the three aforementioned traits.
Empowerment of Grass Roots Communities Through Information-Driven Learning
Authors: Rahman Hakikur
Published: March 2021

Methodologies involving issues to empower remotely distributed communities localized with sub-standard or lower-standard information backbone are still in demand of imperative attention from the policy initiation level in each country. Hence, particular attention should be given to grassroot-level participants in formulating non-conventional approaches to elucidate on demand-driven content by articulating grassroots communities in homogeneous coherence, and at the same time emulating to multifarious conjunctures of socio-economic elements. Efforts have been given in this chapter in synthesizing contents dependent on technologies, meant for distant mode of education and online education including analytical approaches to develop a pragmatic repository of the education system.
Innovation, Ethics, and Consumer Protection
Authors: Prom Tep Sandrine , Cachecho Maya , Jean-Bouchard Évelyne
Published: March 2021

In recent years, firms that rely on fintech to develop and deliver financial products and services have become increasingly important in the banking and financial sector. Nevertheless, fintech products raise various ethical and legal issues, particularly relating to consumer rights. These issues can be analyzed in the light of behavioral law and economics which suggest that prevalent cognitive biases systematically affect the judgment of individuals. To mitigate this bounded rationality, it is possible to guide the decision-making processes through the use of nudges and configured sets of choices. A good example is fintech gamification, defined as the use of game-related mechanisms in other areas, particularly websites or social networks. However, the use of nudges for commercial purposes is often associated with some form of manipulative tactics explicitly aimed at exploiting individuals' biases without their consent. In this context, recourse to the law is useful as it provides for the minimum requirements needed to regulate the relationship between a firm and its customers.
Are ICT Non-Users Absolute Non-Users?
Authors: Joseph Nimmy Maria , Thomas P. E.
Published: March 2021

The level of ICT usage is one of the criteria to measure rural development. Nevertheless, the increasing presence of the “digital divide” indicates that there are setbacks in accomplishing this progress. A deeper understanding about the categorization of users and non-users of technologies is needed as there is an implicit element called ‘potential users' among the non-user category that decides level of ICT usage among people. But the fact is that all are not using the technologies in an equal proportion. The variation is based on different reasons. However, there are people who are interested in ICTs and are unable to explore it. This chapter discusses the categorization of ICT users and non-users and the barriers of potential users for technology use. Thus, measures for transforming potential users to innovators are described. Guiding potential users in handling ICTs may pave the way to enhancing the digital enrichment of rural people. The need for digital freedom is found to be the basic requirement of potential users.
Knowledge Management Portals for Empowering General Public and Societies
Authors: Rahman Hakikur
Published: March 2021

With the advent of the web technologies, portals are providing a wide range of comprehensive support for information processing and management focusing on content management with specific foundation for knowledge development. Knowledge management portals are emerging as web tools that can assist facilitate knowledge management in the aspect of learning, social awareness, policy implementation, and empowering the common citizen of the community. Knowledge management portals can be a rigid platform for providing integrated access to relevant content and resources in one location, for sharing and distributing information, and for bringing the community people together for knowledge interchange. This chapter focuses on the aspects of knowledge management portals through a horizontal literature review and put forwards a few cases that are being utilized in various aspects of the society for the knowledge attainment of the general public of the society.
Turkish Cuisine
Authors: Tekiner İsmail Hakkı
Published: March 2021

Turkish cuisine is one of the richest in the world with its strong historical and intercultural background. Contrary to the common perception, Turkish food culture is not all meat-centric; it has an incredibly rich diversity of vegan choices. Traditional Turkish cuisine also extends to ceremonial and traditional occasions, such as weddings, burial ceremonies, some religious events, circumcisions, migrations, journeys, hosting guests, and welcoming newborns. On these occasions, Turks prepare the best and most loved traditional foods to eat and share together. The prepared foods are mostly vegetarian-friendly, and meat is consumed in very restricted amounts. This paper explores the planet- and vegan-friendly features of the Turkish food culture and its links with folklore.
Adjunctive treatment of myxopapillary ependymoma running head: Myxopapillary ependymoma
Authors: Jahanbakhshi Amin , Najafi Masoumeh , Jafari Fatemeh , Moshtaghian Mahsa , Gomar Marzieh , Anbarlouei Mousareza , Naderi Soheil
Published: March 2021

Myxopapillary ependymoma are rare tumors and optimal therapeutic strategy is remained controversial. The main treatments for myxopapillary ependymoma tumors include surgery and radiotherapy. Hence, the present study aimed to review adjuvant treatment of myxopapillary ependymoma, focusing on spinal myxopapillary ependymoma. The information sources of all articles were the English authoritative databases including PubMed, Web of science, Scopus, Science direct and Google scholar. In this review study, the keywords including adjuvant, treatment, myxopapillary and ependymoma were selected from MeSH medical library. Related articles were published from 2000 to 2020. Given radiation tolerance in the spinal cord is 10-15% lower than that of the brain, it also should be noted that with increased dose and scope of therapeutic field, the corresponding risks are increased, as well. Also, chemotherapy has never been used as the primary treatment approach. Radiotherapy’s value is considered while involving with sensitive areas where chemotherapy is also recommended. Gross total resection is the preferred primary treatment. But the role of adjuvant radiotherapy is debated in different tumor and patient scenarios and no standard treatment strategy had been defined yet. The bottom line is that as long as cellular and molecular methods or gene therapy can be used in the treatment of myxopapillary ependymoma, all the studies confirm that the best treatment method is still wide surgical resection as much as possible.
Étude pétrographique de la syénite à néphéline du Mont Saint-Hilare (Québec)
Authors: Soles J A
Published: March 2021

L'étude pétrographique de la syénite à néphéline de la carrière Désourdy sur le mont Saint-Hilaire (Québec) a démontré que les minéraux nuisibles y sont peu abondants et, qu'en conséquence, la roche
représentée par les échantillons pourrait être utilisée comme agrégat dans les bétons exposés à des températures normales. On doit noter la présence d'un mica secondaire expansible qui pourrait causer la formation de petites alvéoles sur
les surfaces polies exposées aux intempéries.
Testin gof low-strength concrete after standard and accelerated curing
Authors: Malhotra V M
Published: March 2021

Ce rapport concerne une recherche sur la résistance à la compression d'un béton de faible résistance en utilisant la prise standard ou accélérée, ceci en liaison avec le projet "Outardes-3" de la Commission Hydro-électrique
du Québec, Montréal, Québec. La résistance à la compression du béton de prise standard des cylindres d'essais 6 x 12 pouces, avec le ciment portland de basse température, varie entre 120 et 230 lb au pouce carré. Mme à des si faibles résistances, il
n'y a pas d'apparition de dégats aux spécimens par manipulation et par démoulage. La résistance à la compression du béton de prise accélérée, des cylindres 6 x 12 pouces varie depuis un minimum de 380 lb au pouce carré jusqu'un maximum de 610 1b au
pouce carré pour un béton au ciment portland de basse température. Ces valeurs sont environ doubles de la résistanceà la compression des cylindres temoins 6 x 12 pouces, cylindres essayés après 28 1/2 heures de prise standard dans l'atmosphère
humide.
Using reclaimed CO?-process sand
Authors: Murton A E
Published: March 2021

Difficulties were being experienced at the plant of Haley Industries Limited, with the use of reclaimed CO?-process sand. Mixtures made with this sand were difficult to mould because of poor flowability, and there was an increased occurrence of defective
castings. The usual tests for mouldability and flowability did not differentiate between mixtures with good and poor properties. Usability of the mixtures was found to be related to changes with time of green and gassed compressive strength, of permeability, and of density of the test specimens. A
reaction between coatings of silica gel on the grains of reclaimed sand and the new sodium silicate of the mixtures was found to be the main cause of the problem. Probably also contributing were sodium salts and unreacted sodium silicate, which dried out the mixtures. It was also found that the
effect of these ingredients could be eliminated adding 0.5% of 5N NaOH to the mixture.. The order of adding the lye and sodium silicate was not important. When these results were applied at the plant of Haley Industries Limited, mixtures containing 50% reclaimed sand and 50% new sand
were found to have good properties. This is in contrast to the maximum of 25% which could previously be tolerated. The use of 50% reclaimed sand is considered to be a satisfactory objective, and the problem is now. Under control.
A study of the effects of three inorganic zinc coatings on the enviromental cracking of maraging steel
Authors: Biefer G J , Olivier B G
Published: March 2021

In tests on small, highly stressed, bent strips of 18% Ni maraging steel (250 grade) immersed in 3.5% NaCL, it was found that each of the three inorganic zinc coatings (Carbo Zinc 11, Dimetcote 3, and Dimetcote 4) brought about accelerated failures due to
hydrogen embrittlement cracking. The results suggest that it would be advisable to carry out screening tests on other coatings considered for use with crack-sensitive metals before putting the combination into service.
Examination of 3"/50 cal gun barrels
Authors: Bell D R
Published: March 2021

Two 3"/50 cal gun barrels were submitted for examination. One barrel had bulged uniformly, the other had bulged and then burst and a piece had been blown out of it. It was determined that the mechanical properties of the undamaged portions met the specified
minimum requirements. It was estimated that the mechanical properties had been reasonably uniform over the length examined. The chemical compositions of the barrels were similar. No metallurgical or processing deficiencies were apparent. It was concluded that the barrel failures were due solely , to
premature shell explosion.
Characterization of 4½-in. line pipe from Yukon Pipeline System
Authors: Bell D R
Published: March 2021

A short piece of 4 ½ -in. pipe from the Yukon Pipeline System was submitted for characterization. The chemical composition indicated the steel had probably been produced by the acid Bessemer process. The pipe had been manufactured by the lap welding process.
The tensile test results conformed to the requirements of API Std 5L, Grade B. The Charpy V-notch impact transition temperature lay between 90 °F and 120 °F. The pipe was probably produced to the requirements of API Std 5L, Grade B, at a time when acid Bessemer steel and the lap welding
process were acceptable, before 1961.
Smelting ilmenite in a shaft-electric furnace
Authors: Viens G E , Campbell R A , Sirianni G V , Banks G N
Published: March 2021

Ilmenite ore was smelted in this combined shaft-electric furnace unit, both with and without preheating in the shaft. Although only a modest degree of preheating was achieved in the shaft (preheat temperature 430 °C), a saving of 18 per cent in the
electrical energy required was achieved or, conversely, it could be stated that a 20 per cent increase in throughput was achieved without increasing the amount of electrical energy required. A significant degree of sulphur removal from the ore was achieved by the preheating in the shaft. It was
found that the minus 6-mesh material had to be screened out of the ore to achieve the necessary permeability for successful shaft operation. The model of shaft used in this investigation was found to be satisfactory for the preheating of this ore.
Petrography of samples of magnesite rock from Northwest Gender River, Newfoundland
Authors: Soles J A
Published: March 2021

The petrographic study showed that the rock is principally fine-grained magnesite, with abundant talc dispersed in the carbonate or concentrated in bands. Quartz is common locally, and chromite, magnetite and pyrite are minor accessory minerals. Iron is also
present in the magnesite structure. Beneficiation of the magnesite to meet requirements for refractories may be difficult.
Examination of a hull crack from the FHE 400 Hydrofoil, Bras D'Or
Authors: Gilmour J B , Pollard W A
Published: March 2021

An examination of a cracked weld from the hull of the Bras d'Or has failed to indicate the original mode of failure. The crack tip shows evidence of environmental crack propagation but it is unlikely that the original failure was due to this
mechanism.
Metallurgical examination of failure of tank car UTLX 83434
Authors: McDonald R D , Campbell W P
Published: March 2021

Samples were examined from tank car UTLX 83434 which had developed fractures in the region of the sill and shell attachment at a temperature of -34 °C (-30 °F). The examination showed that cracking had initiated at welded joints in the sill support
member and then propagated in a brittle mode upward through the sill support plates and into the shell. Probable initiation sites at the welds were provided by defects such as small root cracks, lack-of-fusion, or small hard spots of uncertain origin on the surface of the weld or adjacent plates.
These hard spots indicated that inadequate stress-relieving had been performed. The shell plate met the chemical requirements of A212 Grade B specification. Other plates involved were not positively identified as to specification but were generally classified as semi-killed carbon steels. The shell
plate did not meet the ultimate strength requirements and was borderline with respect to yield strength, when compared with A212 Grade B specification. The notch-ductility properties of the shell and sill support plates were inadequate for the service conditions. Charpy V-notch testing gave a 15 ft
lb transition temperature of -7 to 4 ° C (20 to 40 °F) for the shell plate and -1 to 4 °C (30 to 40 °F) for the support plate. Drop-weight tests on the shell plate gave a nil-ductility temperature of 4 to 10 °C (40 to 50 °F).
An evaluation of the soild state carbonation process for the recovery of sodium sulfite from waste sulfite pulp liquors
Authors: Kerby R C , Ingraham T R
Published: March 2021

A study was made of several aspects of the solid-state carbonation process for recovering sodium sulfite from waste sulfite pulping liquors. In particular, the kinetics of the solid-state carbonation step of the process were examined in detail. The experimental
results indicated that the optimum conditions for the solid-state carbonation of synthetic smelts are temperatures between 150° and 200°C, with a CO? partial pressure greater than 0.4 atm. and a water vapour partial pressure between 0.05 and 0.10 atm. The reaction is dependent on an
adequate supply of CO? and H?O to the reacting smelt and the rapid removal of the product gas, H?S, from the reaction site.
The adsorption of gold by a lignite char from Manitoba-Saskatchewan Coal Co.
Authors: Gilmore A J
Published: March 2021

A sample of lignite char from Manitoba-Saskatchewan Coal Co. adsorbed monovalent gold up to 100 oz/ton char. However, this lignite char is not as efficient as commercially available carbons for industrial gold recovery from alkaline-cyanide solutions. There would
be no economic advantage in using char because it would be necessary to process an estimated four times more char than carbon to recover the same amount of gold.
Investigation of the web cracks of the replacement main centre foil of the FHE 400 hydrofoil
Authors: Gilmour J B
Published: March 2021

An investigation of the web cracks in the replacement main centre foil of the FHE 400 Hydrofoil has been carried out. All the cracks examined were of an environmental nature and only occurred after the entry of sea water into the foil. The presence of an internal
oxidation subscale on the web plates led to pitting of the maraging steel. The pits, along with the grain boundary oxides which had also been formed by the internal oxidation, provided stress raisers which, in the presence of a high residual welding stress, were sufficient to initiate environmental
cracking.
The Oil Heating Association of Canada Clean Air Program phase I: facilities, techniques and procedures
Authors: Brown T D
Published: March 2021

This report is the first in a series describing the results obtained in an investigation by the Canadian Combustion Research Laboratory and sponsored by the Oil Heating Association of Canada. The investigation has the prime objective of documenting the
performance of available residential oil burning equipment in typical space and hot water heating applications in Canada. The report describes the program, facilities, measurement techniques, and test procedures developed for the investigation.
Failure of an aluminum alloy 81mm cartridge tail unit
Authors: Pollard W A
Published: March 2021

Examination of an 81mm mortar cartridge, which failed in service, has shown that a gross defect introduced during extrusion caused brittle fracture of the part when it was fired. Other units made from the same extruded length would also be defective and should,
if possible, be located and withdrawn from service.
Concentration investigation of drill core sample of ilmenite ore from the Gaston Gauthier Property, St. Urbain, Charlevois County, P.Q.
Authors: Riley G W
Published: March 2021

yes with table
The feasibility of producing a dry-pressed building brick with tailings from Quebec iron mine
Authors: Collings R K , Brown G A
Published: March 2021

La Direction des Mines a reçu début de 1973, une requête de Hilton Iron Mines de Shawville, Québec, afin d'examiner la possibilité d'utilisation de ses résidus de minerai de fer dans la fabrication de briques. Une investigation fut
donc entreprise sur l'utilisation de ces résidus dans cette application en se servant de lignosulfonate de calcium comme agent liant, ce dernier étant un déchet de l'industrie de la pulpe et du papier. Un lien satisfaisant fut obtenu dans les tests préliminaires, lesquels
comportaient l'utilisation de 1 pour cent de lignosulfonate et de 6 pour cent d'eau. Les spécimens d'essai avaient été pressés à 5000 lb/po² et cuits dans un petit four électrique à des températures variant entre 1000 et 1200 ?C pendant une période
de 5 à 6 heures. Il fut cependant constaté que les spécimens se fracturaient à la cuisson, probablement dû au changement de volume du quartz présent, un phénomène qui se produit à 573?C. Ce problème fut toutefois résolu en donnant au
matériel original un broyage plus fin, c'est-à-dire une proportion d'environ 50 pour cent passant le tamis No. 200. D'autres essais de cuisson furent effectués dans un plus grand fourneau. Des spécimens rencontrant les normes de la CSA en regard avec la résistance,
l'absorption et les caractéristiques de gel et dégel furent obtenus après 6 heures de cuisson, cependant, dans une zone de cuisson relativement restreinte (1150 à 1175°C). De la recherche additionnelle, comportant l'utilisation d'additifs afin d'élargir la zone de
cuisson est recommandée.
Investigation of a white granite from the Stanstead area, P.Q.
Authors: Hanes F E
Published: March 2021

Les carrières "Haselton White Granite" produisent une pierre reconnue pour sa blancheur comme l'indique son nom, "Canadiana White". Les résultats d'essais physiques, d'études pétrographiques et d'essais de gel et dégel sur une
période de plus de 1000 cycles démontrent que cette pierre se conforme à toutes les normes d'utilisation comme pierre à construction ou monumentale. Elle est définitivement l'une des plus blanches pierres granitiques grises disponibles dans l'industrie
actuellement.
An investigation to determine causes for the variation in the flotation behaviour of iron ore from Schefferville, Quebec
Authors: Klymowsky I B
Published: March 2021

Des différences ont été constatées dans la quantité de particules mixtes et dans les particularités de la surface des particules de quartz des échantillons étudiés. Les échantillons qui ne donnaient pas de bons
résultats en ce qui concerne la flottation contenaient d'avantage de particules mixtes et deux variétés de particules de quartz: les surfaces des particules de la première sont douces et celles-ci flottent facilement; dans l'autre variété les surfaces sont très
rudes et les particules ne flottent pas. On n'a pas trouvé de particules de cette variété dans les échantillons qui réagissaient bien à la flottation. On a aussi trouvé des différences de textures des échantillons. Les échantillons qui flottent mal
sont de texture oolithique, tandis que ceux qui flottent bien sont de structure plus granulaire. On a constaté une bonne corrélation entre la séparation magnétique et la flottation, ce qui a facilité l'évaluation des échantillons de
minerai.
Welding evaluation of In-787 line-pipe steel
Authors: Gordine J
Published: March 2021

The welding characteristics of IN-787 have been evaluated for the purpose of assessing its potential as an Arctic Grade line-pipe steel. Both its weldability and fieldwelding characteristics were found to be good. Its resistance to heat-affected-zone hydrogen
cracking was found superior to conventional X65 line-pipe steels. laboratory welding tests made at room and low temperatures using conventional, manual, field-welding techniques indicated good welding behaviour with minimal heat-affected-zone hardening. Toughness levels of these welds compared
favourably with welds made in other X65 grade line-pipe steels. Impact tests made on the as-received submerged-arc mill welds showed poor low-temperature impact values. Toughness studies made on simulated heat-affected zones produced in the Gleeble showed that a severe loss of toughness occurs in
the coarse-grained region of the heat-affected zone. The remainder of the heat-affected zone showed toughness levels equivalent to or better than the parent metal.
Metallurgical investigation on carbonaceous gold bearing ore from Agnico-Eagle Mines Ltd.
Authors: Shaheen L E
Published: March 2021

Cyanidation with and without pre-aeration, kerosene passivation, and carbon flotation has been studied on samples of carbonaceous gold ore from Agnico-Eagle Mines Ltd. Gold extractions of 85 to 92% have been obtained by two routes. Kerosene addition to the
whole ore followed by cyanidation offers the simplest metallurgical approach. However, flotation of a carbon concentrate with pre-aeration-cyanidation of the flotation tails and a kerosene-cyanide retreatment of the small volume of carbon concentrate also yields similar gold extractions. This latter
procedure, although more detailed, appears to be the most satisfactory at present, because of the number of pieces of rubber-lined equipment in the circuit which would be attacked by kerosene. Either route will eliminate the adverse effect of carbon adsorption of soluble gold and thereby increase
the present gold extraction to an acceptable level.
Benefication of graphite from Mont Laurier, Quebec (Project MP-IM-7106)
Authors: Hartman F H , Wyman R A
Published: March 2021

Les auteurs ont procédé à des essais de concentration par broyage autogéne, concentration par tables pneumatiques, flottation et séparation magnétique sur un échantillon de graphite de 17.4% de carbone provenant de
Mont-Laurier, Québec. On obtint, par concentration par tables pneumatiques, un concentré de graphite de 78.4% de carbone, ce qui représente une récupération de 12% de carbone basé sur l'alimentation. Ensuite, (1) par le processus de flotation avec une
alimentation moindre que 8 mailles obtenue par broyage autogène, suivie d'un tamisage du produit, on obtint un concentré supérieur â 65 mailles contenant 95.4% de carbone totalisant une récupération de 30% du carbone original. (2) Avec la même alimentation,
mais cette fois fragmentée dans un broyeur à boulets, on obtint-un produit supérieur à 65 mailles contenant 93.5% de carbone, d'une récupération de 46%; le rejet d'une fraction magnétique fut utilisé afin d'améliorer la teneur des
concentrés,
Investigation to determine causes for the poor nickel recoveries in flotation of old asbestos tailings of Carey-Canadian Mines Limited, East Broughton, Quebec
Authors:   Canada Mines Branch
Published: March 2021

On a trouvé que les sulfures de nickel étaient plus finement répartis dans les vieux résidus. Ces sulfures de nickel, à l'état libre, n'étaient pas seulement ternis, mais étaient moins nombreux que dans les résidus
plus récents. A cause de ces facteurs et aussi à cause d'une plus grande tendance des gangues minérales des vieux résidus à flotter, il a été difficile de produire un concentré de nickel satisfaisant. Afin de surmonter ce problème, il a fallu nettoyer les
surfaces des minéraux, soit par broyage ou par traitement à l'acide.
Cyanidation of a gold ore from Paymaster Consolidated Mines Limited, South Porcupine, Ontario
Authors: Berry T F
Published: March 2021

This investigation was initiated in an attempt to locate the reasons for the discrepancy that exists between the percentage of gold extracted from the ore and the percentage, of gold recovered, at Paymaster Consolidated Mines Limited. Cyanidation and
precipitation tests designed to increase, the recovery of gold from the ore were unsuccessful. The presence of nickel in the ore, and its effect on the precipitation of gold, are discussed, and possible solutions to the problem are advanced.
Mineralogy of a uranium ore sample (Ref. No. 1/58-9) from Klerksdorp Consolidated Goldfields Limited, South Africa, submitted by Wright Engineers Limited, Vancouver, B.C.
Authors: Kaiman S
Published: March 2021

Radioactivity occurs in finely disseminated form in the matrix of the pebble conglomerate rock. The grains of uraninite, the main uranium-bearing mineral, are usually less than 200 mesh in size. Zircon, coffinite and monazite account for a small proportion of the
radioactivity.
Ion exchange treatment of solution produced in acid leaching of uranium ore from Amalgamated Rare Earth Mines Limited, Bancroft, Ontario. Ref. No. 7/57-7
Authors: Kornelsen E , McNamara V M
Published: March 2021

An ion-exchange study has been made of the effect of repeated loading, with solution produced in acid leaching of uranium ore from Amalgamated Rare Earth Mines Ltd., Ref. No. 7/57-7, and elution on Amberlite IRA-400 resin. A study of uranium precipitation from
eluate produced by this ion exchange treatment has also been made. No evidence of serious resin poisoning has been observed. Uranium precipitates obtained were satisfactory except for the fact that their thorium content was somewhat high. It is suggested that under plant operating conditions this
latter trouble might not be encountered.
The flotation of acid-consuming minerals from a composite sample representing feed to the custom mill of Lorado Uranium Mines LTD., Uranium City, Saskatchewan - Ref, Nos. 12/57-13 and 12/57-22
Authors: Gow W A
Published: March 2021

Laboratory-scale flotation test work on an ore sample representative of feed to the custom mill of Lorado Uranium Mines Ltd. indicated that the carbonates could be floated from mill feed without difficulty, using sodium carbonate, sodium silicate and oleic acid.
Optimum results were 59% of the carbonates floated in 7. 4% of the feed weight at a grade of 30% CO2. Uranium reporting in the carbonate concentrate amounted to 7. 7% of the total.