Application of the Law of Additive Reaction Times to Fluid–Solid Reactions in Porous Pellets with Changing Effective Diffusivity

2010 ◽  
Vol 41 (6) ◽  
pp. 1261-1267 ◽  
Author(s):  
Hong Yong Sohn ◽  
Silvia E. Perez-Fontes
Keyword(s):  
Reaction Times ◽  
Effective Diffusivity ◽  
The Law ◽  
Additive Reaction

Discussion of “the law of additive reaction times in fluid-solid reactions”

1979 ◽  
Vol 10 (2) ◽  
pp. 295-296
Author(s):  
Y. K. Rao ◽  
S. K. El-Rahaiby ◽  
M. M. Al-Kahtany
Keyword(s):  
Reaction Times ◽  
The Law ◽  
Additive Reaction

scholarly journals Equilibria between Sulfur Rings in Carbon Disulfide Solution at Elevated Temperatures

1982 ◽  
Vol 37 (9) ◽  
pp. 1219-1220 ◽  
Author(s):  
Ralf Steudel ◽  
Reinhard Strauss
Keyword(s):  
Temperature Dependence ◽  
Carbon Disulfide ◽  
Elevated Temperatures ◽  
Equilibrium Constants ◽  
Reaction Times ◽  
Mass Action ◽  
Half Time ◽  
Law Of Mass Action ◽  
Equilibrium Concentrations ◽  
The Law

AbstractCyclooctasulfur, S8, dissolved in CS2 reacts at 130-155 °C in sealed ampoules to give S6 and S7 whose concentrations have been determined by HPLC. The half-time of the reaction is independent of the initial S8 concentration and decreases from 232 min at 130 °C to 64 min at 150 °C. After long reaction times equilibrium concentrations are observed which are in agreement with the law of mass action. From the temperature dependence of the equilibrium constants the following reaction enthalpies (at 130-155 °C) have been calculated: 3/4S8⇌S6 ⊿H°=24kJ/mol7/8S8⇌S7 ⊿H°=21kJ/mol

Ultrastructural identification of three types of sensory setae on copepod antennae

1995 ◽  
Vol 53 ◽  
pp. 956-957
Author(s):  
T. M. Weatherby ◽  
P.H. Lenz
Keyword(s):  
Phase Locking ◽  
Membrane Surface ◽  
Reaction Times ◽  
High Sensitivity ◽  
Structural Features ◽  
Calanoid Copepods ◽  
Marine Food Webs ◽  
Dendritic Membrane ◽  
Ultrastructural Characterization

Crustaceans, as well as other arthropods, are covered with sensory setae and hairs, including mechanoand chemosensory sensillae with a ciliary origin. Calanoid copepods are small planktonic crustaceans forming a major link in marine food webs. In conjunction with behavioral and physiological studies of the antennae of calanoids, we undertook the ultrastructural characterization of sensory setae on the antennae of Pleuromamma xiphias.Distal mechanoreceptive setae exhibit exceptional behavioral and physiological performance characteristics: high sensitivity (<10 nm displacements), fast reaction times (<1 msec latency) and phase locking to high frequencies (1-2 kHz). Unusual structural features of the mechanoreceptors are likely to be related to their physiological sensitivity. These features include a large number (up to 3000) of microtubules in each sensory cell dendrite, arising from or anchored to electron dense rods associated with the ciliary basal body microtubule doublets. The microtubules are arranged in a regular array, with bridges between and within rows. These bundles of microtubules extend far into each mechanoreceptive seta and terminate in a staggered fashion along the dendritic membrane, contacting a large membrane surface area and providing a large potential site of mechanotransduction.

Factors Influencing Cognate Performance for Young Multilingual Children's Vocabulary: A Research Synthesis

2020 ◽  
Vol 29 (4) ◽  
pp. 2170-2188
Author(s):  
Lindsey R. Squires ◽  
Sara J. Ohlfest ◽  
Kristen E. Santoro ◽  
Jennifer L. Roberts
Keyword(s):  
Test Validity ◽  
Reaction Times ◽  
Bilingual Children ◽  
Second Grade ◽  
High Quality Research ◽  
Word Level ◽  
Research Questions ◽  
Word Characteristics ◽  
Study Inclusion ◽  
Task Level

Purpose The purpose of this systematic review was to determine evidence of a cognate effect for young multilingual children (ages 3;0–8;11 [years;months], preschool to second grade) in terms of task-level and child-level factors that may influence cognate performance. Cognates are pairs of vocabulary words that share meaning with similar phonology and/or orthography in more than one language, such as rose – rosa (English–Spanish) or carrot – carotte (English–French). Despite the cognate advantage noted with older bilingual children and bilingual adults, there has been no systematic examination of the cognate research in young multilingual children. Method We conducted searches of multiple electronic databases and hand-searched article bibliographies for studies that examined young multilingual children's performance with cognates based on study inclusion criteria aligned to the research questions. Results The review yielded 16 articles. The majority of the studies (12/16, 75%) demonstrated a positive cognate effect for young multilingual children (measured in higher accuracy, faster reaction times, and doublet translation equivalents on cognates as compared to noncognates). However, not all bilingual children demonstrated a cognate effect. Both task-level factors (cognate definition, type of cognate task, word characteristics) and child-level factors (level of bilingualism, age) appear to influence young bilingual children's performance on cognates. Conclusions Contrary to early 1990s research, current researchers suggest that even young multilingual children may demonstrate sensitivity to cognate vocabulary words. Given the limits in study quality, more high-quality research is needed, particularly to address test validity in cognate assessments, to develop appropriate cognate definitions for children, and to refine word-level features. Only one study included a brief instruction prior to assessment, warranting cognate treatment studies as an area of future need. Supplemental Material https://doi.org/10.23641/asha.12753179

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