scholarly journals Laboratory experiments to unveil the molecular reactivity occurring during the processing of ices in the protosolar nebula

2020 ◽  
Vol 531 ◽  
pp. 116011 ◽  
Author(s):  
T. Gautier ◽  
G. Danger ◽  
O. Mousis ◽  
F. Duvernay ◽  
V. Vuitton ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Molecular Reactivity ◽  
Protosolar Nebula

Dynamics of comets in the collapsing protosolar nebula

1999 ◽  
Vol 173 ◽  
pp. 45-50
Author(s):  
L. Neslušan
Keyword(s):  
Solar System ◽  
Velocity Distribution ◽  
Oort Cloud ◽  
Interstellar Clouds ◽  
Protosolar Nebula ◽  
Moving Bodies

AbstractComets are created in the cool, dense regions of interstellar clouds. These macroscopic bodies take place in the collapse of protostar cloud as mechanically moving bodies in contrast to the gas and miscroscopic dust holding the laws of hydrodynamics. In the presented contribution, there is given an evidence concerning the Solar system comets: if the velocity distribution of comets before the collapse was similar to that in the Oort cloud at the present, then the comets remained at large cloud-centric distances. Hence, the comets in the solar Oort cloud represent a relict of the nebular stage of the Solar system.

Covering of cometary nucleus by refractory crust and its evolution into asteroid-like body

1999 ◽  
Vol 173 ◽  
pp. 365-370
Author(s):  
Kh.I. Ibadinov
Keyword(s):  
Laboratory Experiments ◽  
Cometary Nucleus ◽  
Sublimation Rate ◽  
Cometary Nuclei ◽  
Short Period Comet ◽  
Short Period ◽  
Brightness Decrease ◽  
Crust Thickness ◽  
Ice Sublimation ◽  
Period Comet

AbstractFrom the established dependence of the brightness decrease of a short-period comet dependence on the perihelion distance of its orbit it follows that part of the surface of these cometary nuclei gradually covers by a refractory crust. The results of cometary nucleus simulation show that at constant insolation energy the crust thickness is proportional to the square root of the insolation time and the ice sublimation rate is inversely proportional to the crust thickness. From laboratory experiments resulted the thermal regime, the gas productivity of the nucleus, covering of the nucleus by the crust, and the tempo of evolution of a short-period comet into the asteroid-like body studied.

When Does Voice Have to be More Than Only Listening? Procedural Justice Effects as a Function of Confident Leadership

2010 ◽  
Vol 9 (2) ◽  
pp. 69-78 ◽  
Author(s):  
David De Cremer ◽  
Maarten Wubben
Keyword(s):  
Procedural Justice ◽  
Interaction Effect ◽  
Laboratory Experiments ◽  
Negative Emotions

The present research examined how voice procedures and leader confidence affect participants’ negative emotions and willingness to withdraw. It was predicted that receiving voice would be valued out of instrumental concerns, but only when the enacting leader was high in confidence. Two laboratory experiments indeed showed an interaction between type of voice (pre-decisional vs. post-decisional) and leader’s confidence (low vs. high) on participants’ negative emotions and willingness to withdraw. In particular, post-decision voice only led to more negative responses than did pre-decision voice when the enacting leader was high in confidence. Negative emotions mediated this interaction effect of type of voice on willingness to withdraw. Implications for integrating the leadership and procedural justice literatures are discussed.

Review of Laboratory Experiments in Psychology.

1968 ◽  
Vol 13 (10) ◽  
pp. 536-536
Author(s):  
Peter G. Polson
Keyword(s):  
Laboratory Experiments

Calibration 7" – Cutthroat Flume as New Size for Discharge Measurement at Free Flow Condition

2020 ◽  
Vol 38 (12A) ◽  
pp. 1783-1789
Author(s):  
Jaafar S. Matooq ◽  
Muna J. Ibraheem
Keyword(s):  
Steady State ◽  
Flow Condition ◽  
Laboratory Experiments ◽  
Free Flow ◽  
Experimental Program ◽  
Steady State Flow ◽  
Empirical Formulas ◽  
State Flow ◽  
Operation Conditions ◽  
Throat Width

 This paper aims to conduct a series of laboratory experiments in case of steady-state flow for the new size 7 ̋ throat width (not presented before) of the cutthroat flume. For this size, five different lengths were adopted 0.535, 0.46, 0.40, 0.325 and 0.27m these lengths were adopted based on the limitations of the available flume. The experimental program has been followed to investigate the hydraulic characteristic and introducing the calibrated formula for free flow application within the discharge ranged between 0.006 and 0.025 m3/s. The calibration result showed that, under suitable operation conditions, the suggested empirical formulas can accurately predict the values of discharge within an error ± 3%.

PRÁTICA LABORATORIAL DE PESQUISA SEDIMENTOLÓGICA

2019 ◽  
Vol 21 (2) ◽  
pp. 218-226
Author(s):  
Alyne Karollayne Melquiades Souza Silva ◽  
Joanderson Fernandes Simões ◽  
Júlio César Reis Silva ◽  
Amanda Cristina Dias Lima ◽  
Marcelo Santos Chaves ◽  
...  
Keyword(s):  
Undergraduate Students ◽  
Experimental Research ◽  
Laboratory Experiments ◽  
Rio Grande ◽  
Physical Geography ◽  
Laboratory Work ◽  
Theoretical Knowledge ◽  
Laboratory Experience

Esta pesquisa teve como finalidade relatar experiências em laboratório, especificamente o Laboratório de Geografia Física - Pesquisa (LabGeoFis-Pesquisa), localizado no Departamento de Geografia, no Centro de Ciências Humanas, Letras e Artes, da Universidade Federal do Rio Grande do Norte. Procuramos relatar, de forma concisa, as principais técnicas aplicadas ao trabalho laboratorial, enfatizado a temática da Geografia Física. Para tecer essas considerações, nos fundamentamos em autores como Venturi (2005) e Rudio (1990), os quais tratam sobre teorias e procedimentos relacionados às práticas de laboratório e a pesquisa descritiva e experimental, respectivamente. Para realizar esta pesquisa, levamos em consideração os trabalhos e as experiências desenvolvidas pelos alunos de bacharelado e licenciatura do primeiro período do curso de Geografia. Os resultados aqui obtidos, nos mostraram a importância dos conhecimentos teóricos aliados com a prática de laboratório.Palavras chaves: Laboratório; Experiência; Técnicas. ABSTRACT This research had the purpose of reporting laboratory experiments, specifically the Laboratory of Physical Geography - Research (LabGeoFis-Search), located in the Department of Geography, at the Humanities, Letters and Arts Center of the Federal University of Rio Grande do Norte. We try to report, in a concise way, the main techniques applied to laboratory work, emphasizing the theme of Physical Geography. In order to make these considerations, we base ourselves on authors such as Venturi (2005) and Rudio (1990), who deal with theories and procedures related to laboratory practices and descriptive and experimental research, respectively. To carry out this research, we take into account the work and experiences developed by the baccalaureate and undergraduate students of the first period of the Geography course. The results obtained here showed us the importance of theoretical knowledge allied with laboratory practice.Keywords: Laboratory; Experience; Technique. RESUMENEl propósito de esta investigación fue reportar experimentos de laboratorio, específicamente el Laboratorio de Investigación de Geografía Física (LabGeoFis-Pesquisa), ubicado en el Departamento de Geografía, en el Centro de Humanidades, Letras y Artes, Universidad Federal de Río Grande del Norte.

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