scholarly journals A parametric study of the coalescence of liquid drops in a viscous gas

2014 ◽  
Vol 753 ◽  
pp. 279-306 ◽  
Author(s):  
James E. Sprittles ◽  
Yulii D. Shikhmurzaev
Keyword(s):  
Parameter Space ◽  
Gas Dynamics ◽  
Scaling Laws ◽  
Practical Interest ◽  
Conventional Model ◽  
Liquid Drops ◽  
Viscous Gas ◽  
Initial Stage ◽  
Large Parameter Space

AbstractThe coalescence of two liquid drops surrounded by a viscous gas is considered in the framework of the conventional model. The problem is solved numerically with particular attention paid to resolving the very initial stage of the process which only recently has become accessible both experimentally and computationally. A systematic study of the parameter space of practical interest allows the influence of the governing parameters in the system to be identified and the role of viscous gas to be determined. In particular, it is shown that the viscosity of the gas suppresses the formation of toroidal bubbles predicted in some cases by early computations where the gas’ dynamics was neglected. Focusing computations on the very initial stages of coalescence and considering the large parameter space allows us to examine the accuracy and limits of applicability of various ‘scaling laws’ proposed for different ‘regimes’ and, in doing so, reveal certain inconsistencies in recent works. A comparison with experimental data shows that the conventional model is able to reproduce many qualitative features of the initial stages of coalescence, such as a collapse of calculations onto a ‘master curve’ but, quantitatively, overpredicts the observed speed of coalescence and there are no free parameters to improve the fit. Finally, a phase diagram of parameter space, differing from previously published ones, is used to illustrate the key findings.

scholarly journals A LONGITUDINAL INVESTIGATION OF EXPLICIT AND IMPLICIT AUDITORY PROCESSING IN L2 SEGMENTAL AND SUPRASEGMENTAL ACQUISITION

2021 ◽  
pp. 1-23
Author(s):  
Hui Sun ◽  
Kazuya Saito ◽  
Adam Tierney
Keyword(s):  
Adult Learners ◽  
Auditory Processing ◽  
First Language ◽  
Neural Representation ◽  
Immersion Experience ◽  
Initial Stage ◽  
Chinese Learners ◽  
Processing Ability ◽  
Speech Learning

Abstract Precise auditory perception at a subcortical level (neural representation and encoding of sound) has been suggested as a form of implicit L2 aptitude in naturalistic settings. Emerging evidence suggests that such implicit aptitude explains some variance in L2 speech perception and production among adult learners with different first language backgrounds and immersion experience. By examining 46 Chinese learners of English, the current study longitudinally investigated the extent to which explicit and implicit auditory processing ability could predict L2 segmental and prosody acquisition over a 5-month early immersion. According to the results, participants’ L2 gains were associated with more explicit and integrative auditory processing ability (remembering and reproducing music sequences), while the role of implicit, preconscious perception appeared to be negligible at the initial stage of postpubertal L2 speech learning.

scholarly journals Welfare optimization and multinational monopolies

1996 ◽  
Vol 38 (1) ◽  
pp. 16-25
Author(s):  
A. M. Russell ◽  
C. A. Martini ◽  
J. A. Rickard
Keyword(s):  
Parameter Space ◽  
Home Country ◽  
Domestic Market ◽  
Consumption Tax ◽  
Optimal Value ◽  
National Welfare ◽  
Consumption Taxes

AbstractThis paper examines the role of import tariffs and consumption taxes when a product is supplied to a domestic market by a foreign monopoly via a subsidiary. It is assumed that there is no competition in the domestic market from internal suppliers. The home country is able to levy a profits tax on the subsidiary. The objective of our analysis is to determine the mix of tariff and consumption tax which simultaneously maximizes national welfare. We show that national welfare does not have an internal maximum, but attains its maximum on a boundary of the consumption tax–tariff parameter space. Furthermore, the optimal value of national welfare increases as the tariff decreases and the consumption tax increases. The results obtained generalize the results of an earlier paper in which national welfare was maximized with respect to either a tariff or consumption tax, but not both.

Incorporation and Role of Nitrogen During Oxynitridation of Silicon Studied by Photoelectron Spectroscopy

1999 ◽  
Vol 567 ◽  
Author(s):  
Masayuki Suzuki ◽  
Yoji Saito
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Oxide Films ◽  
Silicon Surfaces ◽  
Gaseous Mixtures ◽  
X Ray ◽  
Initial Stage ◽  
Thermal Stability Of

ABSTRACTWe tried direct oxynitridation of silicon surfaces by remote-plasma-exited nitrogen and oxygen gaseous mixtures at 700°C in a high vacuum. The oxynitrided surfaces were investigated with in-situ X-ray photoelectron spectroscopy. With increase of the oxynitridation time, the surface density of nitrogen gradually increases, but that of oxygen shows nearly saturation behavior after the rapid increase in the initial stage. We also annealed the grown oxynitride and oxide films to investigate the role of the contained nitrogen. The desorption rate of oxygen from the oxynitride films is much less than that from oxide films. We confirmed that nitrogen stabilizes the thermal stability of these oxynitride films.

scholarly journals The role of drop shape in impact and splash

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Qingzhe Liu ◽  
Jack Hau Yung Lo ◽  
Ye Li ◽  
Yuan Liu ◽  
Jinyu Zhao ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Spherical Geometry ◽  
Impact Dynamics ◽  
Helmholtz Instability ◽  
Liquid Drops ◽  
Drop Shape ◽  
Spreading Dynamics ◽  
Solid Substrates ◽  
The Impact

AbstractThe impact and splash of liquid drops on solid substrates are ubiquitous in many important fields. However, previous studies have mainly focused on spherical drops while the non-spherical situations, such as raindrops, charged drops, oscillating drops, and drops affected by electromagnetic field, remain largely unexplored. Using ferrofluid, we realize various drop shapes and illustrate the fundamental role of shape in impact and splash. Experiments show that different drop shapes produce large variations in spreading dynamics, splash onset, and splash amount. However, underlying all these variations we discover universal mechanisms across various drop shapes: the impact dynamics is governed by the superellipse model, the splash onset is triggered by the Kelvin-Helmholtz instability, and the amount of splash is determined by the energy dissipation before liquid taking off. Our study generalizes the drop impact research beyond the spherical geometry, and reveals the potential of using drop shape to control impact and splash.

Arthrocladiella mougeotii. [Descriptions of Fungi and Bacteria].

1998 ◽  
Author(s):  
V. P. Heluta
Keyword(s):  
Czech Republic ◽  
Geographical Distribution ◽  
Disease Transmission ◽  
Russian Far East ◽  
Far East ◽  
Republic Of Georgia ◽  
Lycium Barbarum ◽  
Initial Stage ◽  
High Infection

Abstract A description is provided for Arthrocladiella mougeotii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Powdery mildew of Lycium species only. The mycelium, conidiophores, conidia and ascomata form first white, then dirty-grey patches on damaged green parts of the host. Infected parts are deformed slightly and, in cases of high infection, plants can lose their ornamental qualities. Damaged leaves can fall prematurely. HOSTS: Lycium barbarum (= L. europaeum), L. chinense, L. dasystemum, L. halimifolium, L. ovatum, L. potaninii, L. rhombifolium, L. ruthenicum. [Type host - Lycium barbarum] GEOGRAPHICAL DISTRIBUTION: Africa: Canary Islands. Asia (temperate areas only): Armenia, Azerbaijan, China, Republic of Georgia, Israel, Japan, Kazakhstan, Kirghizistan, Korea, Russia (Russian far east), Tadzhikistan, Taiwan, Turkey, Turkmenistan, Uzbekistan. Australasia: New Zealand (introduced). Europe: Austria, Belgium, Bulgaria, Czech Republic, Estonia, France, Germany, Hungary, Italy, Netherlands, Norway, Poland, Rumania, Slovakia, Sweden, Switzerland, UK, Ukraine (southern), former Yugoslavia. North America: USA (introduced). TRANSMISSION: By wind-dispersed conidia. The rôle of ascospores in disease transmission is unknown, although it has been supposed that they can cause the initial stage of the disease.

Significance of analysis of the mechanism of fingermarks formation, sizes and location – casework examples

2018 ◽  
Vol 301 ◽  
pp. 44-52
Author(s):  
Tomasz Kowalski ◽  
Keyword(s):  
Significant Role ◽  
Special Interest ◽  
The Other ◽  
Fatal Accident ◽  
Preliminary Stage ◽  
Additional Information ◽  
Expert Opinions ◽  
First Case ◽  
Initial Stage

The aim of the article to present the role of analysing the manner of generating fingermarks in the investigative proceedings. These examinations are based on the analysis of the location of the marks on a given background and aim at providing the requesting party additional information about the circumstances of the investigated incident. The Author refers to two unusual cases, in which Voivodeship Police Command Forensic Laboratory issued expert opinions in the area of fingerprint identification. In the first case, at the initial stage of the proceedings the circumstances and recovered evidential fingermarks indicated a fatal accident or manslaughter by means of a firearm. In the other case at the preliminary stage recovered evidence did not allow identification of the perpetrator due to incorrectly selected exhibits. These cases would not be off special interest to us without the significant role of proper recovering of fingermarks and their analysis in a broader context than just identification.

To the clinic of infected ulcers of the stomach and duodenum

1927 ◽  
Vol 23 (5) ◽  
pp. 516-523
Author(s):  
S. A. Grosman ◽  
M. M. Brailovsky
Keyword(s):  
Clinical Manifestation ◽  
Surgical Intervention ◽  
Secondary Infection ◽  
Practical Interest ◽  
Point Of View ◽  
French School

We will not touch the controversial question of the role of infection in the genesis of ulcers and will adopt the point of view of the French school (Duval, Roux, Montier, Girault), for which the concept of an infected ulcer is only a concept of a pathological-anatomical and clinical nature, related to the concept of the evolution of an already existing ulcer, depending on its secondary infection. This evolution of the ulcer, in the presence of a new ingredient of infection, creates some peculiarities in its clinical manifestation,-peculiarities which, in suitable cases, can and must be taken into account both in the choice of time and in the choice of method of surgical intervention. Thus, the question under consideration by us has not only theoretical character, but, as we will try to state below, acquires also a certain practical interest.

Motivation for Reading of Students from initial stage of primary education (1st to 4th Grade)

2020 ◽  
Vol 28 (1) ◽  
Author(s):  
Diana Vatsova ◽  
◽  
◽  
Keyword(s):  
Primary Education ◽  
Cognitive Processes ◽  
Fourth Grade ◽  
Building Element ◽  
Literary Education ◽  
Initial Stage ◽  
Fourth Grade Students ◽  
Competency Based ◽  
Education Of Students

The article discusses one of the areas of the literary education of students in the initial stage of primary education: developing interest in reading. The timeliness and relevance of the problem treated determine the purpose of the study: based on international pedagogical experience, to define a model that increases the interest in reading within the competency-based approach, and highlight the role of motivation as a building element of this model. Analyses of the structure of motivation for reading, and the means of integration of cognitive processes and creativity when working with artistic text are done, being the aim to increase the motivation for reading of first to fourth grade students.

THE GEOLOGICAL ROLE OF THE SEARCH METHOD "WILD CAT WELLS" IN THE STUDY OF THE HYDROCARBON POTENTIAL OF THE PRIPYAT TROUGH

2021 ◽  
pp. 148-168
Author(s):  
Yaroslav G. Gribik
Keyword(s):  
Search Method ◽  
Hydrocarbon Potential ◽  
Geological Exploration ◽  
Positive Role ◽  
Oil Reserves ◽  
Hydrocarbon Traps ◽  
Deep Wells ◽  
Initial Stage ◽  
Exploratory Wells

The results of geological exploration for oil within the Elsky, Shatilkovsky, Savichsky and Petrikovsko-Shestovichsky sections of the Pripyat trough are analyzed. The analysis covers almost 70 years from the drilling of the first exploratory wells laid by the "wild cat" method to the modern comprehensive justification. During the analyzed period, from 12 to 23 deep wells were drilled with a total penetration of 42.3 thousand meters to 68.3 thousand meters in each section. The initial stage of work after the first oil inflow is characterized by a higher activity of drilling new exploratory wells, justified by the methods available at that time. The negative result of exploratory drilling in certain areas is also due to the significant fragmentation of the intrasalt perspective horizons and the areal unevenness of reservoir layers in the subsalt complex. Within the boundaries of the sites, deposits with recoverable oil reserves of no more than 450 thousand tons are established, which can be determined as a low economic efficiency of prospecting operations. However, the work has played a positive role in determining real models of hydrocarbon traps for use in the study of other sites.

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