Results 31 to 40 of about 15,990 (212)

Synthesis of High cis‐Polybutadiene in Styrene Solution with Neodymium‐Based Catalysts: Towards the Preparation of HIPS and ABS via In Situ Bulk Polymerization

International Journal of Polymer Science, Volume 2016, Issue 1, 2016., 2016
In a first step, 1,3‐butadiene was selectively polymerized at 60°C in styrene as solvent using NdV3/DIBAH/EASC as the catalyst system. The catalyst system activation process, the addition order of monomers and catalyst components, and the molar ratios [Al]/[Nd] and [Cl]/[Nd] were studied.
Ramón Díaz de León, Florentino Soriano Corral, Francisco Javier Enríquez-Medrano, Gabriela Bosques Ibarra, Patricia de León Martínez, Francisco Hernández Gámez, Héctor Ricardo López-González, Luis Francisco Ramos de Valle, Atsushi Sudo   +8 more
wiley   +1 more source

Características de estudiantes con talento en la escritura académica de las licenciaturas en educación y en enseñanza del inglés

Aula
Esta investigación presenta un acercamiento a las características del talento en la escritura académica de estudiantes universitarios de las licenciaturas en Educación y en Enseñanza del Inglés, situado en los catalizadores ambientales e intrapersonales ...
Diana Irasema Cervantes Arreola, Dalia Lizette Gómez Martínez, Óscar Martín Vázquez Reyes   +2 more
doaj   +1 more source

KnowCat: Catalizador de Conocimiento

, 2001
KnowCat is a distributed non-supervised system for structuring knowledge. KnowCat stands for "Knowledge Catalyser" and its purpose is enabling the crystallisation of collective knowledge as the result of user interactions. One of the applications of the system is the generation of quality educational materials as the automatic result of student ...
Cobos Pérez, Ruth, Alamán Roldán, Xavier, Esquivel, José A.   +2 more
openaire   +2 more sources

Facets of Crises: How Problem Indicators and Public Perceptions Affect Policy Change

Policy Studies Journal, EarlyView.
ABSTRACT Crises are widely acknowledged as catalysts for policy change. Yet, our understanding of the policy effects of crises remains limited. Why do only some crises lead to major changes, while significant policy changes also occur during seemingly non‐crisis periods?
Constantin Kaplaner, Alexa Lenz, Vanessa Millich, Christoph Knill, Yves Steinebach, Clara Fochler, Annika Kolbe   +6 more
wiley   +1 more source

Changes in the transformative potential of action proposals in Finnish Red Lists from 1986 to 2019

Conservation Biology, Volume 40, Issue 4, August 2026.
Abstract Red lists provide critical knowledge regarding biodiversity decline, especially in Finland, where broad assessments have been made regularly since the 1980s. They deliver information on the threat status of species and ecosystems, propose actions to guide conservation policy, and have the potential to spur transformative change.
Anni Arponen, Anna Salomaa, Henna Fabritius, Aino Juslén, Saija Kuusela   +4 more
wiley   +1 more source

Desarrollo de catalizadores de cobre soportados sobre esferas de celulosa para eliminar contaminantes emergentes en agua [PDF]

, 2020
Los contaminantes emergentes se encuentran frecuentemente en los efluentes acuosos deindustrias químicas, farmacéuticas y petroquímicas, siendo los procesos de oxidación avanzada(POA), tales como oxidación catalítica húmeda con H 2 O 2 (CWPO) una buena ...
Nudel, Exequiel Nicolas, Marchesini, Fernanda Albana, Devard, Alejandra Veronica, Taleb, María Claudia, Olmos, Graciela Viviana   +4 more
core   +1 more source

The frequency and importance of polyploidy in tropical rainforest tree radiations

New Phytologist, Volume 249, Issue 4, Page 2103-2114, February 2026.
Summary The presence of more than two copies of the genome in an organism, termed ‘polyploidy’, is a crucial force in plant evolution, generating genetic, phenotypic and ecological diversity. [Correction added on 22 January 2026, after first online publication: the preceding sentence has been corrected.] The Amazonian tree flora is the most species ...
Rowan J. Schley, Rosalía Piñeiro, James A. Nicholls, Michelle L. Gaynor, Gwilym P. Lewis, Flávia Fonseca Pezzini, Kyle G. Dexter, Catherine Kidner, R. Toby Pennington, Alex D. Twyford   +9 more
wiley   +1 more source

Urban Transformations, Emergencies, and Disasters in Los Angeles: Constructing Civilian Unpreparedness as a Public Policy Issue (1940–1980) 洛杉矶的城市转型、紧急情况和灾害:将公民的准备不足建构为公共政策问题(1940年至1980年) Transformaciones Urbanas, Emergencias y Desastres En Los Ángeles: La Construcción De La Falta De Preparación Civil Como Un Problema De Política Pública (1940–1980)

Risk, Hazards &Crisis in Public Policy, Volume 16, Issue 3, September 2025.
ABSTRACT This article explores the sociohistorical construction of civilian unpreparedness as a public policy issue in Los Angeles, arguing that it emerged not as a neutral response to escalating urban risks, but as a mechanism through which actors negotiated power dynamics amid urban transformations between 1940 and 1980.
Piero Tellerías Melgarejo
wiley   +1 more source

Obtención de catalizadores ácidos a partir de la cascarilla de arroz

Mutis, 2017
En este artículo se presenta la obtención de sílice a partir de la cascarilla de arroz, y su aplicación en la síntesis de catalizadores ácidos sólidos.
Jeisson Javier Loaiza Malaver, Ana María Campos Rosario   +1 more
doaj   +1 more source

HIDROGENACIÓN DE CROTONALDEHÍDO SOBRE CATALIZADORES Ir/TiO2-SiO2

Dyna, 2009
Se estudió la hidrogenación de crotonaldehído en fase líquida, sobre catalizadores Ir/TiO2-SiO2; este aldehído es altamente contaminante y proviene de fuentes tan diversas como humo de tabaco, gases de escape de motores de gasolina o diesel y humo de combustión de madera [1].
ROJAS, HUGO, BORDA, GLORIA, MURCIA, JULIE, REYES, PATRICIO, ROJAS, NÉSTOR   +4 more
openaire   +4 more sources