Jove
Visualize
Contáctanos
JoVE
x logofacebook logolinkedin logoyoutube logo
ACERCA DE JoVE
Visión GeneralLiderazgoBlogCentro de Ayuda JoVE
AUTORES
Proceso de PublicaciónConsejo EditorialAlcance y PolíticasRevisión por ParesPreguntas FrecuentesEnviar
BIBLIOTECARIOS
TestimoniosSuscripcionesAccesoRecursosConsejo Asesor de BibliotecasPreguntas Frecuentes
INVESTIGACIÓN
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchivo
EDUCACIÓN
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualCentro de Recursos para ProfesoresSitio de Profesores
Términos y Condiciones de Uso
Política de Privacidad
Políticas

Videos de Conceptos Relacionados

Exponential Functions with Base e01:30

Exponential Functions with Base e

240
Exponential functions with base e are essential for modeling continuous processes of growth and decay. The constant e, approximately 2.718, naturally arises in systems where change occurs proportionally to the current value. A positive exponent represents continuous growth, while a negative exponent represents continuous decay. These functions are especially useful for describing situations where change happens smoothly over time rather than in discrete steps.One clear example of exponential...
240
Applications of Integration to Probability Density Functions01:27

Applications of Integration to Probability Density Functions

51
Continuous probability distributions are used to model random variables that can take on any real value within a specified range. These variables do not take on isolated or countable values but rather exist on a continuum. For example, the height of an individual can be measured with increasing precision—such as 163.5 or 165.25 centimeters—demonstrating that height is a continuous random variable.The behavior of such variables is described using a probability density function (PDF),...
51
What is Behavior?00:54

What is Behavior?

10.3K
Behaviors are actions that an organism engages in—they can be related to finding food, reproducing, defending against threats, and many other possible actions. Behaviors include activities related to the environment around the animal—such as migration—as well as social interactions within a species or population. Many behaviors involve motor output—that is, muscle movements—while others involve less visible actions, such as learning.
10.3K
Body Temperature01:25

Body Temperature

4.2K
The body's temperature, measured in degrees, is determined by the balance between heat production and dissipation to the surrounding environment. For instance, if exercising vigorously, the body will produce more heat, causing sweat and dissipating that heat. Despite extreme environmental conditions and physical exertion, the human temperature-control system maintains a constant core body temperature (the temperature of deep tissues, which are the tissues located beneath the skin and other...
4.2K
Body Temperature01:07

Body Temperature

1.4K
Body temperature reflects the equilibrium between heat production and heat loss within the body. Most heat is generated by metabolically active tissues, particularly the liver, heart, brain, kidneys, and endocrine organs. At rest, skeletal muscles contribute 20–30% of total heat production, but during vigorous exercise, this can increase up to 30–40 times.
The average body temperature is approximately 37°C (98.6°F) and typically ranges from 36.1–37.2°C...
1.4K
Effects of Temperature on Free Energy02:11

Effects of Temperature on Free Energy

28.2K
The spontaneity of a process depends upon the temperature of the system. Phase transitions, for example, will proceed spontaneously in one direction or the other depending upon the temperature of the substance in question. Likewise, some chemical reactions can also exhibit temperature-dependent spontaneities. To illustrate this concept, the equation relating free energy change to the enthalpy and entropy changes for the process is considered:
28.2K

También podría leer

Artículos Relacionados

Artículos vinculados a este trabajo por autores compartidos, revista y gráfico de citas.

Ordenar por
Same author

Closed Loop of Polyurethanes: Effect of Isocyanate Index on the Properties of Repolyols and Rebiopolyols Obtained by Glycolysis.

Materials (Basel, Switzerland)·2025
Same author

Chemolysis of Bio-Based Polyurethane Foams with Different Biopolyol Contents: Recovery and Possibility of Rebiopolyols Reuse in Sustainable Polyurethane Systems.

Materials (Basel, Switzerland)·2025
Same author

Toward Fully Bio-Based Polyurethane Foams: Effects of Radish Seed and Tall Oil Polyols on Biofoam Properties.

Materials (Basel, Switzerland)·2025
Same author

Turning Fruit Seed Oils into High-Performance Open-Cell Polyurethane Foams: A Green Route to Petrochemical Polyol-Free Insulation.

Materials (Basel, Switzerland)·2025
Same author

<i>Brassica carinata</i> and <i>Camelina sativa</i> oils as renewable raw materials for producing viscoelastic polyurethane foams.

RSC advances·2025
Same author

Riboflavin as a Dual-Function Additive for Enhancing Biodegradation in Piezoelectric PLA/BT Composites.

Materials (Basel, Switzerland)·2025

Video Experimental Relacionado

Updated: Jan 29, 2026

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids
10:28

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

Published on: January 3, 2014

15.5K

Espumas de Poliuretano Viscoelásticas de Base Biológica: Comportamiento Funcional en Temperaturas de Aplicación

Elżbieta Malewska1, Konstantinos N Raftopoulos1, Piotr Rytlewski2

  • 1Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.

Polymers
|January 28, 2026
PubMed
Resumen
Este resumen es generado por máquina.

Este estudio explora espumas de poliuretano viscoelásticas hechas con polioles de base biológica de aceite de coco y grasas. Estas espumas ecológicas muestran potencial para aplicaciones de mobiliario, ofreciendo buenas propiedades viscoelásticas y absorción de energía.

Palabras clave:
temperatura de aplicaciónpoliuretanoespumas viscoelásticas

Más Videos Relacionados

Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper
06:36

Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper

Published on: February 27, 2021

4.2K
Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer
08:47

Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer

Published on: April 21, 2022

3.9K

Videos de Experimentos Relacionados

Last Updated: Jan 29, 2026

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids
10:28

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

Published on: January 3, 2014

15.5K
Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper
06:36

Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper

Published on: February 27, 2021

4.2K
Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer
08:47

Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer

Published on: April 21, 2022

3.9K

Área de la Ciencia:

  • Ciencia de los Materiales
  • Química de Polímeros
  • Materiales Sostenibles

Sus antecedentes:

  • Las espumas de poliuretano se utilizan ampliamente pero a menudo dependen de materias primas de origen petrolero.
  • El desarrollo de alternativas sostenibles a partir de recursos de base biológica es crucial para la reducción del impacto ambiental.
  • Los biol- polioles ofrecen una ruta potencial para una producción de poliuretano más ecológica.

Objetivo del estudio:

  • Investigar la síntesis y propiedades de espumas de poliuretano viscoelásticas utilizando biol- polioles novedosos.
  • Evaluar el impacto de diferentes tipos de biol- polioles (aceite de coco, aceite de palma, grasa de pato, grasa de cerdo) y concentraciones en las características de la espuma.
  • Evaluar el rendimiento térmico, mecánico y viscoelástico de estas espumas de base biológica para aplicaciones potenciales.

Principales métodos:

  • Se incorporaron cuatro biol- polioles (aceite de coco, aceite de palma, grasa de pato, grasa de cerdo) en formulaciones de poliuretano (5-20 % en peso).
  • Se analizó la estabilidad térmica a través de estudios de descomposición.
  • Se probaron las propiedades mecánicas y el comportamiento viscoelástico en un rango de temperatura de -20 a 40 °C.
  • Se evaluaron las características de histéresis y amortiguación.

Principales resultados:

  • La incorporación de biol- el polioles resultó en una descomposición temprana menor pero mejoró ligeramente la estabilidad térmica general.
  • La temperatura de transición vítrea se mantuvo estable, alrededor de 10 °C.
  • Las espumas exhibieron propiedades viscoelásticas adecuadas para mobiliario a 20 y 40 °C.
  • Los biol- polioles de aceite de coco y grasa de pato mejoraron la absorción de energía y la amortiguación.

Conclusiones:

  • Las espumas de poliuretano de base biológica demuestran potencial como materiales ecológicos y de alto rendimiento.
  • Los biol- polioles derivados del aceite de coco y la grasa de pato producen una absorción de energía superior.
  • El rendimiento a temperaturas inferiores a 10 °C puede verse limitado por una mayor rigidez, lo que sugiere idoneidad para aplicaciones específicas.