Continuous Formation Process of CO2Gas Hydrate via a Vortex and Impinging Stream Reactor

Jing Bai; Deqing Liang; Dongliang Li; Shuanshi Fan; Jianwei Du; Xingxue Dai; Zhen Long

doi:10.1021/ef900694z

A metodologia do percurso de estudo e pesquisa adaptada à formação inicial e continuada de professores de matemáticaMethodology of the study and research performance adapted to initial and continued training of mathematics teachers

Educação Matemática Pesquisa Revista do Programa de Estudos Pós-Graduados em Educação Matemática ◽

10.23925/1983-3156.2018v20i1p448-470 ◽

2018 ◽

Vol 20 (1) ◽

Author(s):

Fernando Cardoso de Matos ◽

José Carlos de Souza Pereira ◽

José Messildo Viana Nunes ◽

Renato Borges Guerra ◽

Saddo Ag Almouloud

Keyword(s):

Mathematics Teachers ◽

Research Methodology ◽

Formation Process ◽

Research Performance ◽

French Language ◽

Work Study ◽

Continuous Formation ◽

Research Activities ◽

Methodological Aspects

Neste artigo objetivamos explicitar alguns aspectos metodológicos das noções originais do Percurso de Estudo e Pesquisa (parcours d’étude et de recherche, em francês), que os dois primeiros autores adaptaram como parte da metodologia de suas pesquisas de teses doutorais. As discussões teóricas são as que constam nos textos originais, na Língua Francesa, dos quais traduzimos alguns trechos. As noções teóricas dos dispositivos didáticos de Trabalho Pessoais orientados, Atividades de Estudo e Pesquisa e Percurso de Estudo e Pesquisa norteiam o corpo textual das duas sessões do artigo. Na segunda sessão expomos as adaptações metodológicas do PER, que conduziram as pesquisas doutorais dos dois primeiros autores. As conclusões indicam que a metodologia do PER, com as devidas adaptações, possibilita um processo de formação inicial e continuada de professores de matemática intermediado pela pedagogia do questionamento, conforme prever esse dispositivo didático e metodológico. In this article we aim to explain some methodological aspects of the original notions of the Study and Research Path (PER), which the first two authors adapted as part of their thesis research methodology. The theoretical discussions are those that appear in the original texts, in the French language, of which we translate some sections. The theoretical notions of didactic devices of Guided Personal Work, Study and Research Activities and Study and Research Path guide the textual body of the article. we present the methodological adaptations of the PER that led the researches of the two doctoral theses. The conclusions indicated that the methodology of the PER, with the appropriate adaptations, allows an initial and continuous formation process of teachers of mathematics intermediated by the pedagogy of questioning, as predicted by this didactic and methodological device.

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All-Fiber Measurement of Surface Tension Using a Two-Hole Fiber

Sensors ◽

10.3390/s20154219 ◽

2020 ◽

Vol 20 (15) ◽

pp. 4219

Author(s):

Jose R. Guzman-Sepulveda ◽

Daniel A. May-Arrioja ◽

Miguel A. Fuentes-Fuentes ◽

Natanael Cuando-Espitia ◽

Miguel Torres-Cisneros ◽

...

Keyword(s):

Surface Tension ◽

Formation Process ◽

Bubble Formation ◽

Fresnel Reflection ◽

Experimental Realization ◽

Capillary Channel ◽

Fiber Core ◽

Continuous Formation

An all-fiber approach is presented to measure surface tension. The experimental realization relies on the use of a specialty fiber, a so-called two-hole fiber (THF), which serves a two-fold purpose: providing a capillary channel to produce bubbles while having the means to measure the power reflected at the end facet of the fiber core. We demonstrate that provided a controlled injection of gas into the hollow channels of the THF, surface tension measurements are possible by simply tracking the Fresnel reflection at the distal end of the THF. Our results show that the characteristic times involved in the bubble formation process, from where the surface tension of the liquids under test is retrieved, can be measured from the train of pulses generated by the continuous formation and detachment of bubbles.

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Formation process of periodic non-conservative antiphase boundary structure in L-Pd5Ce

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173947 ◽

1990 ◽

Vol 48 (4) ◽

pp. 162-163

Author(s):

Masaru Itakura ◽

Noriyuki Kuwano ◽

Kensuke Oki

Keyword(s):

Formation Process ◽

Domain Size ◽

Antiphase Boundary ◽

Boundary Structure ◽

Temperature Phase ◽

Arc Melting ◽

Iced Water ◽

Antiphase Domains ◽

Low Temperature Phase ◽

Degree Of Order

The low temperature phase of Pd5Ce (L-Pd5Ce) has a one-dimensional long period superstructure (1D-LPS) derived from Ll2. The periodic antiphase boundaries (APBs) are parallel to (110) planes and have a shift vector of 1/2[110]. Hereafter, the indices are referred to the basic lattices of Ll2 As insertion of the APB causes a change in composition, such an APB is called “non-conservative”. Then, a domain size M depends upon the Ce concentration in the alloy. It was found that M increases also with temperature. The temperature dependency of M is attributed to a change of the degree of order within the antiphase domains. In this work, morphology of the non-conservative APBs is observed to clarify the formation process of the 1D-LPS.The alloy of Pd-16.7 at%Ce was prepared by arc melting in argon atmosphere. Disc specimens made from the alloy ingot were first held at 985 K for 260 ks and quenched in iced water to obtain the state of M=∞ or Ll2, followed by annealing for various lengths of time. The annealing temperature was 873 K where the equilibrium value for M is about 3 in unit of (110) lattice spacing of Ll2. Observation was carried out using microscopes JEM-2000FX, JEM-4000EX (HVEM Lab., Kyushu Univ.) and JEM-2000EX (Dept. of Mater. Sci. Tech., Kyushu Univ.).

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