Search results for "Heat"

Peltier’s and Thomson’s coefficients of thermoelectric phenomena in the observable formulation

2011

Four transport coefficients characterize the thermoelectric properties of materials. Three of them are widely measured and studied. But the number of references on the Peltier coefficient are very limited. This unequal result is a consequence of the Onsager reciprocal relation (ORR). A review on the preciseness and accuracy of Peltier coefficient measurements has been developed in this paper. Thus we can appreciate a low level in the experimental confirmation for the ORR. In order to describe the thermoelectric processes in an advantageous way, the observable formulation has been used. This is characterized by the electric potential measured at the probe terminals and for the heat flux whic…

Rotating magnetic fields as a means to control the hydrodynamics and heat/mass transfer in the processes of bulk single crystal growth

1999

The report discusses the possibility of using different types of rotating magnetic fields (RMF) and combinations of these to control the hydrodynamics and heat/mass transfer in the processes of bulk semiconductor single crystal growth. Some factors contributing to the efficiency of RMF influence in different technologies are analysed. Their specific practical application is illustrated by some examples.

A conformationally adaptive macrocycle : conformational complexity and host–guest chemistry of zorb[4]arene

2018

Large amplitude conformational change is one of the features of biomolecular recognition and is also the basis for allosteric effects and signal transduction in functional biological systems. However, synthetic receptors with controllable conformational changes are rare. In this article, we present a thorough study on the host–guest chemistry of a conformationally adaptive macrocycle, namely per-O-ethoxyzorb[4]arene (ZB4). Similar to per-O-ethoxyoxatub[4]arene, ZB4 is capable of accommodating a wide range of organic cations. However, ZB4 does not show large amplitude conformational responses to the electronic substituents on the guests. Instead of a linear free-energy relationship, ZB4 foll…

Decipher the mechanisms of protein conformational changes induced by nucleotide binding through free-energy landscape analysis: ATP binding to Hsp70.

2013

ATP regulates the function of many proteins in the cell by transducing its binding and hydrolysis energies into protein conformational changes by mechanisms which are challenging to identify at the atomic scale. Based on molecular dynamics (MD) simulations, a method is proposed to analyze the structural changes induced by ATP binding to a protein by computing the effective free-energy landscape (FEL) of a subset of its coordinates along its amino-acid sequence. The method is applied to characterize the mechanism by which the binding of ATP to the nucleotide-binding domain (NBD) of Hsp70 propagates a signal to its substrate-binding domain (SBD). Unbiased MD simulations were performed for Hsp…

A Computational Approach to Conjugate Heat Transfer between Two Fluids in Plate Heat Exchangers of Arbitrary Geometry

2002

PROTEZIONE E MIGLIORAMENTO DELLE PRESTAZIONI ANTINCENDIO NEI TEATRI ALL’ITALIANA. FIRE PROTECTION AND PERFORMANCE UPGRADE IN ITALIAN STYLE THEATRES

2018

Se storicamente gli incendi sono stati la causa principale di distruzione di molti teatri all’italiana, ancora in un recente passato interventi di conservazione, restauro e adeguamento alle norme antincendio, in alcuni casi incolti e irrispettosi, ne hanno stravolto gli elementi architettonico-costruttivi caratterizzanti. Come per ogni edificio storico, ancor più nei Teatri, in cui l’effimero connota molte parti della costruzione, è necessario garantire oltre alla salvaguardia delle vite umane, la protezione dell’edificio e del suo valore intrinseco. Il processo per raggiungere livelli adeguati di prestazioni e sicurezza antincendio pone pertanto molte sfide per i legislatori, i progettisti…

Covering the Gap for an Effective Energy and Environmental Design of Green Roofs: Contributions from Experimental and Modelling Researches

2021

AbstractGreen roofs are components of the building envelope that have become increasingly popular in urban contexts because other than providing numerous environmental benefits they are also capable of reducing building energy consumption, especially in summer. However, despite all these advantages, green roofs are still affected by some limitations. Specifically, there are some gaps affecting the energy modelling consisting in the absence of a proper database, information (growth stage, leaf area index, and coverage ratio) relative to the different green roof plant species, which technicians could use in case of lack of actual field data to perform energy analysis of buildings equipped wit…

A statistical-dynamical downscaling for the urban heat island and building energy consumption - Analysis of Its uncertainties.

2020

AbstractHigh-resolution maps of the urban heat island (UHI) and building energy consumption are relevant for urban planning in the context of climate change mitigation and adaptation. A statistical–dynamical downscaling for these parameters is proposed in the present study. It combines a statistical local weather type approach with dynamical simulations using the mesoscale atmospheric model Meso-NH coupled to the urban canopy model Town Energy Balance. The downscaling is subject to uncertainties related to the weather type approach (statistical uncertainty) and to the numerical models (dynamical uncertainty). These uncertainties are quantified for two French cities (Toulouse and Dijon) for …

A Case-Study of Green Roof Monitoring: The Building of Council for Agricultural Research and Economics in Bagheria, (Italy)

2018

The energy saving in building goes on as an important challenge in the policy of Developed Countries. While the issue of energy building efficiency in heating season has deeply been investigated for a long time, the issue of energy building efficiency in cooling season is relatively recent. Moreover, considering the increase of electric consumption for air-conditioning in summer, mainly due to the growing quality of life, the research of technologies for reducing energy building consumption during this season becomes essential. The green roof represents a technology useful to reduce the energy consumption during the cooling season. In this work the authors report the results of a monitoring…

Alkali consumption of aliphatic carboxylic acids during alkaline pulping of wood and nonwood feedstocks

2013

Abstract The carbohydrate degradation products have been examined, which are formed during the conventional kraft pulping of a softwood, hardwoods, bamboo, and wheat straw as well as soda and soda-anthraquinone pulping of wheat straw. The focus was on “volatile” acids such as formic and acetic acids and “nonvolatile” hydroxy monocarboxylic and dicarboxylic acids. The different consumption profiles were obtained for the charged alkali required for the neutralization of these aliphatic acids depending on the feedstock and the cooking method. The relative composition of the acid fraction in the black liquors of softwood and hardwood and nonwood feedstocks showed characteristic variations. Howe…