Revisiting the supplementary relationship of dynamic contact angles measured by sessile-droplet and captive-bubble methods: Role of surface roughness

The engineering applications of spreading and adhesion phenomena involving fluids on solids are numerous. The adhesive and spreading interactions at the solid-fluid interfaces are well characterized by dynamic contact angles. This study reports on the results of an experimental investigation into the effect of solid surface roughness on dynamic contact angles in solid-liquid-liquid (S-L-L) systems. The experiment involved the use of Wilhelmy Plate apparatus to measure adhesion tension (which is the product of interfacial tension and cosine of the contact angle between the liquid-liquid interface and the solid surface), the DuNuoy tensiometer to measure the liquid-liquid interfacial tension, and a profilometer to characterize the roughness of the solid surfaces used. The components of the solid-liquid-liquid systems studied consisted of: (i) smooth glass, roughened quartz and an actual rock surface for the solid phase, (ii) normal-hexane and deionized water as the two immiscible liquid phases. The dynamic contact angles (advancing and receding angles) of the three-phase (rock-oil-water) system provide essential information about the wettability of petroleum resrvoirs. The wettability of a reservoir is an important parameter that affects oil recovery in primary, secondary, and enhanced recovery operations [1]. Contact angle measurements on smooth surfaces are generally used to characterize reservoir wettability. However pore surfaces within reservoir rocks are essentially rough and hence it is important to determine the effect of such roughness on measured contact angles. There is very little information in the open literature on the effect of surface roughness on dynamic contact angles in S-L-L systems. In the present work, four levels of roughness of solid surfaces of similar mineralogy (quartz and glass) were tested in hexane-deionized water fluid pair. The advancing and receding contact angles measured at ambient conditions were analyzed for wettability effects. It was found that as surface roughness increased, the dynamic contact angles also increased. The wettability of the rock-oil-water system shifted from weakly water-wet for the smooth glass to intermediate-wet for the roughened surface. The general trends observed in our study were found to be in good agreement with other published results. However, the generally held notion of increasing contact angle hysteresis with increasing roughness appears to be incorrect in solid-liquid-liquid systems.

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Water–propylene glycol sessile droplet shapes and migration: Marangoni mixing and separation of scales

Journal of Fluid Mechanics ◽

10.1017/jfm.2021.1030 ◽

2022 ◽

Vol 933 ◽

Author(s):

J. Charlier ◽

A.Y. Rednikov ◽

S. Dehaeck ◽

P. Colinet ◽

D. Terwagne

Keyword(s):

Contact Angle ◽

Propylene Glycol ◽

Ambient Air ◽

Contact Angles ◽

Apparent Contact Angle ◽

Sessile Droplet ◽

Convective Mixing ◽

Separation Of Scales ◽

And Migration

New light is shed on morphological features of water–propylene glycol sessile droplets evaporating into ambient air at not too high relative humidity. Such droplets adopt a Marangoni-contracted shape even on perfectly wetting substrates, an effect well known since Cira et al. (Nature, 519, 2015). We here highlight a strong separation of scales normally occurring for such droplets. Namely, there is a narrow high-curvature zone localized at the foot of the droplet, where the apparent contact angle is formed, while the core of the droplet merely adheres to the classical (capillary–gravity) static shape. Experimentally, we rely upon interferometry to discern such fine key details. We detect a maximum of the droplet slope profile in the foot region, which amounts to the apparent contact angle. Theoretically, a local description of the foot region is devised. We indicate a crucial role of convective mixing by the solutal Marangoni flow, here accounted for by the Taylor dispersion, which proves to underlie the separation of scales and ensure self-consistency of the local model. Migration of such droplets in a humidity gradient is also approached within the same experimental and theoretical framework. It is considered that the resulting back–front asymmetry of the apparent contact angles drives the motion similarly to a wettability gradient, although the drag (‘Cox–Voinov’) factor is here found to be different. The predictions, comparing well with the measurements (our own and from the literature), are based on rigorous models, isothermal and as reduced as possible, without any fitting parameters or microphysics effects.

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Attachment Styles, Physical Proximity, and Relational Satisfaction

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000062 ◽

2014 ◽

Vol 4 (2) ◽

pp. 106-112

Author(s):

Anita Shrivastava ◽

Andrea Burianova

Keyword(s):

Attachment Styles ◽

Romantic Relationship ◽

Distinct Type ◽

Relational Satisfaction ◽

Long Distance ◽

Avoidant Attachment ◽

Geographic Separation ◽

Relationship Of ◽

Attachment Dimensions

This study aimed to explore the relationships between attachment styles, proximity, and relational satisfaction. This was achieved by assessing a distinct type of long distance romantic relationship of flying crews, compared with proximal (non-flying crew) romantic relationships. The responses of 139 expatriate professionals revealed significant associations between proximity and anxious and avoidant attachment dimensions. The role of the avoidant dimension in comparison with that of the anxious dimension was found to be a significant predictor of relational satisfaction. This study contributes significantly toward addressing the role of proximity and attachment in relational satisfaction in a new context of geographic separation.

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PERSEPSI PEMAHAMAN PERANAN AUDITOR, ETIKA AUDITOR DAN INDEPENDENSI AUDITOR INTERNAL DALAM MEWUJUDKAN GOOD UNIVERSITY GOVERNANCE DENGAN GAYA KEPEMIMPINAN SEBAGAI VARIABEL MODERASI

BALANCE Jurnal Akuntansi dan Bisnis ◽

10.32502/jab.v4i1.1796 ◽

2019 ◽

Vol 4 (1) ◽

pp. 474

Author(s):

Fipitriany Any

Keyword(s):

Leadership Style ◽

University Governance ◽

Primary Data ◽

Study Program ◽

Internal Auditor ◽

Internal Auditors ◽

Analysis Models ◽

Relationship Of ◽

Role Ethics

ABSTRACT The purpose of this study is to examine and analyze the influence of the role, ethics, and independence of internal auditors in implementing good university governance (GUG) with leadership style as a moderation variable. Multiple linear regression and moderation regression analysis models are used to test the hypothesis. The primary data are obtained through questionnaires that are distributed to the respondents, namely the dean and head of study program at the UniversitasBinaDarma and UniversitasMuhammadiyahPalembang. The results of this study indicate that the instruments in each variable proved to be valid and reliable. Based on the results of hypothesis testing, it can be seen that simultaneously the variable of role, ethics, and independence of internal auditors have positively and significantly effect in implementing good university governance (GUG). These results provide justification or endorsement of the theoretical truths used as the theoretical references of Stewardship Theory and Attitude and Behavioral Theory. Based on the partial test, role of auditor does not significantly affect the variable of GUG, but ethics and independence variable are found to be significant in influencing GUG. The leadership style is negative and insignificant in moderating the role of internal auditors and GUC and also the independence of internal auditor and GUC. The leadership style is found to be positive and insignificant in moderating the relationship of internal auditors’ ethics and GUC.Keywords Role, Ethics, Independence, Internal Auditor, Leadership Style, Good University Governance ABSTRAK Tujuan dari penelitian ini adalah untuk menguji dan menganalisis pengaruh peran, etika, dan independensi auditor internal dalam menerapkan good university governance (GUG) dengan gaya kepemimpinan sebagai variabel moderasi. Model analisis regresi linier berganda dan regresi moderasi digunakan untuk menguji hipotesis. Data primer diperoleh melalui kuesioner yang dibagikan kepada responden, yaitu dekan dan ketua program studi di Universitas Bina Darma dan Universitas MuhammadiyahPalembang. Hasil penelitian ini menunjukkan bahwa instrumen dalam setiap variabel terbukti valid dan dapat diandalkan. Berdasarkan hasil pengujian hipotesis dapat dilihat bahwa secara simultan variabel peran, etika, dan independensi auditor internal berpengaruh positif dan signifikan dalam penerapan good university governance (GUG). Hasil ini memberikan pembenaran atau pengesahan kebenaran teoretis yang digunakan sebagai referensi teoretis dari Teori Penatalayanan dan Teori Sikap dan Perilaku. Berdasarkan uji parsial, peran auditor tidak secara signifikan mempengaruhi variabel GUG, tetapi variabel etika dan independensi ditemukan signifikan dalam mempengaruhi GUG. Gaya kepemimpinan negatif dan tidak signifikan dalam memoderasi peran auditor internal dan GUC dan juga independensi auditor internal dan GUC. Gaya kepemimpinan ditemukan menjadi positif dan tidak signifikan dalam memoderasi hubungan etika auditor internal dan GUC Kata Kunci Peran, Etika, Independensi, Auditor Internal, Gaya Kepemimpinan, Tata Kelola Universitas

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Management of Economics and State "Bottom"

Issues of Risk Analysis ◽

10.32686/1812-5220-2020-17-6-76-91 ◽

2020 ◽

Vol 17 (6) ◽

pp. 76-91

Author(s):

E. D. Solozhentsev

Keyword(s):

Quality Of Life ◽

Artificial Intelligence ◽

Probabilistic Models ◽

Human Life ◽

Special Software ◽

Human Quality ◽

Relationship Of ◽

The Relationship

The scientific problem of economics “Managing the quality of human life” is formulated on the basis of artificial intelligence, algebra of logic and logical-probabilistic calculus. Managing the quality of human life is represented by managing the processes of his treatment, training and decision making. Events in these processes and the corresponding logical variables relate to the behavior of a person, other persons and infrastructure. The processes of the quality of human life are modeled, analyzed and managed with the participation of the person himself. Scenarios and structural, logical and probabilistic models of managing the quality of human life are given. Special software for quality management is described. The relationship of human quality of life and the digital economy is examined. We consider the role of public opinion in the management of the “bottom” based on the synthesis of many studies on the management of the economics and the state. The bottom management is also feedback from the top management.

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On Metaphysics and the Political: A Polemics of Reading Baudelaire in the 1930s

Nottingham French Studies ◽

10.3366/nfs.2019.0252 ◽

2019 ◽

Vol 58 (2) ◽

pp. 249-259

Author(s):

Joseph Acquisto

Keyword(s):

Twentieth Century ◽

Political Crisis ◽

The Political ◽

Modern Poetry ◽

Progressive Politics ◽

The World ◽

Relationship Of ◽

The Relationship ◽

Insight Into

This essay examines a polemic between two Baudelaire critics of the 1930s, Jean Cassou and Benjamin Fondane, which centered on the relationship of poetry to progressive politics and metaphysics. I argue that a return to Baudelaire's poetry can yield insight into what seems like an impasse in Cassou and Fondane. Baudelaire provides the possibility of realigning metaphysics and politics so that poetry has the potential to become the space in which we can begin to think the two of them together, as opposed to seeing them in unresolvable tension. Or rather, the tension that Baudelaire animates between the two allows us a new way of thinking about the role of esthetics in moments of political crisis. We can in some ways see Baudelaire as responding, avant la lettre, to two of his early twentieth-century readers who correctly perceived his work as the space that breathes a new urgency into the questions of how modern poetry relates to the world from which it springs and in which it intervenes.

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STEROID HORMONE METABOLISM IN RESPONSIVE TISSUES IN VITRO

Acta Endocrinologica ◽

10.1530/acta.0.068s279 ◽

1971 ◽

Vol 68 (1_Suppl) ◽

pp. S279-S294 ◽

Cited By ~ 12

Author(s):

Paul Robel

Keyword(s):

Steroid Hormone ◽

Physiological Activity ◽

Physiological State ◽

Target Cells ◽

Target Tissue ◽

Hormone Metabolism ◽

Metabolizing Enzymes ◽

Relationship Of

ABSTRACT Of the information available on steroid hormone metabolism in responsive tissues, only that relating hormone metabolism to physiological activity is reviewed, i. e. metabolite activity in isolated in vitro systems, binding of metabolites to target tissue receptors, specific steroid hormone metabolizing enzymes and relationship of hormone metabolism to target organ physiological state. Further, evidence is presented in the androgen field, demonstrating 5α-reduced metabolites, formed inside the target cells, as active compounds. This has led to a consideration of testosterone as a »prehormone«. The possibility that similar events take place in tissues responding to progesterone is discussed. Finally, the role of hormone metabolism in the regulation of hormone availability and/or renewal in target cells is discussed. In this context, reference is made to the potential role of plasma binding proteins and cytosol receptors.

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Significance and Role of Athletes in Ethical Education of Youth

Physical Education and Sport Through the Centuries ◽

10.2478/spes-2019-0013 ◽

2019 ◽

Vol 6 (2) ◽

pp. 62-74

Author(s):

Ivana Markov Čikić ◽

Aleksandar Ivanovski

Keyword(s):

Young People ◽

Role Models ◽

Role Model ◽

Modern Society ◽

Ethical Education ◽

Open Issue ◽

Clear Identification ◽

Relationship Of

Summary One cannot write about the relationship of young people and current sports stars in modern society without having previously studied the processes of mediation and globalisation of sport, and the transformation of traditional social values. The goal of the science and practice engaged in sports and education of young people is a constant quest for preserving universal ethical values and reconciling them with the modern-day social processes. This paper will present the result of a survey conducted with adolescents in five different Serbian cities in order to find the answer to the question if sportspersons were their favourite television role-models. According to the results of our survey, 45% of adolescents do not have a favourite TV personality and do not know for sure who that could be. Novak Đoković, who would be the choice of adults for a role model of the young, with 63.2% according to the survey conducted by the Ministry of Youth and Sports, scored 3.81% in our survey with adolescents who would chose Novak Đoković as their favourite TV personality. The necessity of raising media literacy of young people with the aim of clear identification of sports role models who are going to improve their quality of life still remains an open issue for further research on this course.

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SECTANITY IN THE CONTEXT OF MANIFESTATIONS OF MODERN RELIGIOUS EXTREMISM

Law and law: problems of theory and practice ◽

10.29039/02033-3/173-178 ◽

2020 ◽

Author(s):

Pavel Agapov ◽

Kirill Stepkin

Keyword(s):

Russian Federation ◽

Religious Extremism ◽

The Russian Federation ◽

Relationship Of ◽

The Relationship ◽

Theoretical Foundations

The article considers the general theoretical foundations of the relationship of sectarianism and religious extremism in the Russian Federation. Practical examples of the role of destructive sects in modern religious extremism in the Russian Federation are given.

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Editor's Note

Constellations ◽

10.29173/cons28832 ◽

2017 ◽

Vol 8 (1) ◽

Author(s):

Emily Kaliel

Keyword(s):

Civil War ◽

Public Memory ◽

Historical Memory ◽

Historical Analysis ◽

Red River ◽

Cultural Institutions ◽

Economic Rights ◽

The Past ◽

Relationship Of

The articles published in our Fall 2016 edition are connected loosely under the themes of public memory and the uses of identity in the past. We are thrilled to present to you three excellent articles in our Fall 2016 edition: The article "Dentro de la Revolución: Mobilizing the Artist in Alfredo Sosa Bravo's Libertad, Cultura, Igualdad (1961)" analyzes Cuban artwork as multi-layered work of propaganda whose conditions of creation, content, and exhibition reinforce a relationship of collaboration between artists and the state-run cultural institutions of post-revolutionary Cuba; moving through fifty years of history “’I Shall Never Forget’: The Civil War in American Historical Memory, 1863-1915" provides a captivating look at the role of reconciliationist and emancipationist intellectuals, politicians, and organizations as they contested and shaped the enduring memory of the Civil War; and finally, the article “Politics as Metis Ethnogenesis in Red River: Instrumental Ethnogenesis in the 1830s and 1840s in Red River” takes the reader through a historical analysis of the development of the Metis identity as a means to further their economic rights. We wholly hope you enjoy our Fall 2016 edition as much as our staff has enjoyed curating it. Editors Jean Middleton and Emily Kaliel Assistant Editors Magie Aiken and Hannah Rudderham Senior Reviewers Emily Tran Connor Thompson Callum McDonald James Matiko Bronte Wells

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