Video Experimental Relacionado
Updated: Jun 9, 2025
09:23
Author Spotlight: Advancing Energy Solutions Using Nanocomposites as Processed Thermoelectric Materials
Published on: May 17, 2024
1.5K
Soluciones basadas en materiales pasivos para ciudades frías y "radiantes"
1Xiaobo Yinis professor of mechanical engineering and professor of physics (by courtesy) at the University of Hong Kong.
Science (New York, N.Y.)
|October 31, 2024
Resumen
Las olas de calor récord están afectando cada vez más a las principales ciudades del mundo, incluidas Tokio, Río de Janeiro, Delhi y Hong Kong. Estos eventos de temperaturas extremas ponen de relieve la necesidad urgente de abordar los desafíos climáticos urbanos.
Área de la Ciencia:
- Ciencias del medio ambiente
- Clima urbano
- Salud pública
Sus antecedentes:
- Las temperaturas récord son cada vez más frecuentes en las zonas urbanas densamente pobladas de todo el mundo.
- Las recientes olas de calor en América del Sur, la India y Japón demuestran el creciente impacto del calor extremo.
- Hong Kong ha experimentado años consecutivos de temperaturas récord de verano.
Objetivo del estudio:
- Para documentar y analizar los recientes eventos de calor extremo en las principales ciudades del mundo.
- Para resaltar la creciente frecuencia de temperaturas récord en centros urbanos densamente poblados.
- Para subrayar la creciente amenaza del calor extremo para las poblaciones urbanas.
Principales métodos:
- Compilación de datos de los registros de temperatura de Tokio, Río de Janeiro y Delhi.
- Análisis de las recientes tendencias de las olas de calor en América del Sur, India y Asia Oriental.
- Observación de las anomalías de temperatura en Hong Kong durante los últimos tres veranos.
Principales resultados:
- Tokio superó los 35°C en septiembre de 2024, estableciendo un nuevo récord.
- Río de Janeiro registró un índice de calor de 62,3°C durante una reciente ola de calor.
- Delhi superó los 50°C en mayo, y Hong Kong ha batido récords de temperatura durante tres veranos consecutivos.
Conclusiones:
- Los eventos de calor extremo son una preocupación creciente en las ciudades más pobladas del mundo.
- La frecuencia y la intensidad de las olas de calor urbanas requieren una acción climática urgente y estrategias de adaptación.
- El seguimiento y la investigación continuos son cruciales para comprender y mitigar los impactos del calor urbano.
Videos de Conceptos Relacionados
01:26Design Example: Sustainability in Concrete Building
161
As the construction industry moves towards more eco-friendly practices, concrete's adaptability and its ability to incorporate sustainable features make it a key material in the drive towards greener building solutions.
There are multiple approaches to achieve sustainability in a commercial concrete building. For instance, construct a concrete parking area under the building, utilizing pervious concrete paver blocks in open areas to facilitate rainwater collection through an underground...
There are multiple approaches to achieve sustainability in a commercial concrete building. For instance, construct a concrete parking area under the building, utilizing pervious concrete paver blocks in open areas to facilitate rainwater collection through an underground...
161
01:17Passive Diffusion: Overview and Kinetics
422
Passive diffusion is a critical process that allows small lipophilic drugs to cross the cell membrane along a concentration gradient. This mechanism's efficiency depends on four primary factors: the membrane's surface area, the drug's lipid-water partition coefficient, the concentration gradient, and the membrane's thickness.
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
422
01:20Hot Weather Concreting
57
Concreting at elevated temperatures accelerates the hydration process, leading to quicker setting but potentially reducing the long-term strength of the concrete structure. Additionally, low air humidity fosters rapid moisture loss from the concrete, resulting in reduced workability, pronounced plastic shrinkage, and a higher likelihood of crazing.
Mitigating the heat increase in concrete can be economically achieved by shading aggregate stockpiles to prevent heating from solar radiation,...
Mitigating the heat increase in concrete can be economically achieved by shading aggregate stockpiles to prevent heating from solar radiation,...
57
01:22Mass Concreting
59
Mass concreting refers to the process of placing large volumes of concrete, such as in gravity dams. The heat generated during the cement hydration process and differential cooling rates within the concrete mass can lead to a temperature gradient, which can result in thermal cracks in the concrete mass.
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...
59
01:20Conduction, Convection and Radiation: Problem Solving
1.2K
There are three methods by which heat transfer can take place: conduction, convection, and radiation. Each method has unique and interesting characteristics, but all three have two things in common: they transfer heat solely because of a temperature difference; and the greater the temperature difference, the faster the heat transfer.
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
1.2K
01:17Radiation: Applications
1.1K
The average temperature of Earth is the subject of much current discussion. Earth is in radiative contact with both the Sun and dark space; it receives almost all its energy from the radiation of the Sun and reflects some of it into outer space. Dark space is very cold, about 3 K, so Earth radiates energy into it. For instance, heat transfer occurs from soil and grasses, the rate of which can be so rapid that frost can occur on clear summer evenings, even in warm latitudes.
The average...
The average...
1.1K