scholarly journals Built-in moisture in cross-laminated timber roofs – a field study

2021 ◽  
Vol 2069 (1) ◽  
pp. 012051
Author(s):  
J E Gaarder ◽  
T D Pettersen
Keyword(s):  
Field Study ◽  
Exposure Level ◽  
Low Carbon ◽  
Large Area ◽  
Construction Time ◽  
Drying Time ◽  
Protection Measures ◽  
Cross Laminated Timber ◽  
Horizontal Orientation ◽  
Run Off

Abstract Cross-Laminated Timber (CLT) elements have had a growing popularity in recent years due to i.e. low carbon footprint, low weight and efficient construction time. However, the elements are sensitive to moisture and prone to organic growth if not treated properly or if used incorrectly. Roof slabs are particularly exposed, as they have a large area of exposure and the horizontal orientation doesn’t allow rainwater run-off. The efforts made to protect CLT-roofing elements by Norwegian contractors vary widely, as there are few guidelines and little long-term experience. A field study of CLT-roofs on existing buildings was conducted to investigate the conditions after some years in service. The study includes inspection and moisture measurements of CLT elements from the exterior side in 10 building projects 1-9 years old from two regions of Norway. The contractor of each project was interviewed in order to assess the extent of climate exposure and protection measures during construction. The results indicate a correlation between water content, building age and exposure level during construction. There is a clear indication that the drying time for built-in moisture in CLT roof constructions are slow. Keeping built-in moisture to a minimum is therefore paramount.

scholarly journals Will organic thermoelectrics get hot?

2019 ◽  
Vol 377 (2152) ◽  
pp. 20180352 ◽  
Author(s):  
Mariano Campoy-Quiles
Keyword(s):  
Carbon Nanotubes ◽  
Persistence Length ◽  
Charge Carrier Mobility ◽  
Small Scale ◽  
Heat Sources ◽  
Low Carbon ◽  
Energy Materials ◽  
Thermoelectric Efficiency ◽  
Large Area ◽  
Low Toxicity

The generally low energy density from most heat sources—the Sun, Earth as well as most human activities—implies that solid-state thermoelectric devices are the most versatile heat harvesters since, unlike steam engines, they can be used on a small scale and at small temperature differences. In this opinion piece, we first discuss the materials requirements for the widespread use of thermoelectrics. We argue that carbon-based materials, such as conducting polymers and carbon nanotubes, are particularly suited for large area and low-temperature operation applications, as they are abundant, low-toxicity and easy to process. We combine experimentally observed macro-trends and basic thermoelectric relations to evaluate the major performance limitations of this technology thus far and propose a number of avenues to take the thermoelectric efficiency of organic materials beyond the state of the art. First, we emphasize how charge carrier mobility, rather than charge density, is currently limiting performance, and discuss how to improve mobility by exploiting anisotropy, high persistence length materials and composites with long and well-dispersed carbon nanotubes. We also show that reducing thermal conductivity could double efficiency while reducing doping requirements. Finally, we discuss several ways in which composites could further boost performance, introducing the concept of interface engineering to produce phonon stack-electron tunnel composites. This article is part of a discussion meeting issue ‘Energy materials for a low carbon future'.

Phase Field Study on the Austenite/Ferrite Transition in Low Carbon Steel

2010 ◽  
Vol 25 (1-3) ◽  
pp. 106-110 ◽  
Author(s):  
Pil-Ryung Cha ◽  
Jin-You Kim ◽  
Won-Tae Kim ◽  
Seong Gyoon Kim
Keyword(s):  
Carbon Steel ◽  
Field Study ◽  
Phase Field ◽  
Low Carbon Steel ◽  
Low Carbon

scholarly journals GEOECOLOGICAL ASSESSMENT OF POLLUTION BY OIL PRODUCTS IN THE VICINITY OF THE BOGANDINSKY SETTLEMENT OF THE TYUMEN REGION

2021 ◽  
Vol 31 (2) ◽  
pp. 152-158
Author(s):  
S.S. Davtyan ◽  
Yu.V. Petrov
Keyword(s):  
Field Study ◽  
Environmental Protection ◽  
Oil Products ◽  
Fuel Oil ◽  
Dual Use ◽  
Protection Measures ◽  
Household Activities ◽  
Environmental Legacy ◽  
The Village

The working settlement of Bogandinsky being a large industrial suburban settlement of the Tyumen district of the Tyumen region, significantly affects the geoecological situation in the municipality. A distinctive negative geoecological feature of the environs of the village of Bogandinsky is the identification of areas of unfavorable environmental legacy from the household activities of dual-use facilities, characterized by the long-term development of conditions for pollution with oil products, primarily fuel oil. To conduct a geoecological assessment of the environs of the village of Bogandinsky, Tyumensky district, studies were carried out, as a result of which pollution with oil products was established on an area of more than 7 thousand sq. m. The results of the field study formed the basis for the development of recommendations for the organization of environmental protection measures.

scholarly journals Güneş Enerjisi Destekli Kurutma Yöntemlerinin Gıda Endüstrisinde Kullanımı

2019 ◽  
Vol 7 (8) ◽  
pp. 1100
Author(s):  
Vildan Top ◽  
İsmail Tontul ◽  
Selman Türker
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Shelf Life ◽  
Nutrient Content ◽  
Drying Methods ◽  
Drying Method ◽  
Large Area ◽  
Drying Time ◽  
The Past ◽  
Storage Units

Dried products are widely used from the past because of their long shelf life, rich nutrient content and availability. Solar or shade drying methods have become the most widely used drying technique from past to date, due to no equipment requirement, cost and simplicity. However, this drying method has some disadvantages such as long drying time, contamination risk and requirement of large area and heavy labor. In this review, various drying methods applied in food are summarized. Then, solar energy assisted drying methods were examined in detail. Finally, solar energy-assisted drying methods involving energy storage are examined. Solar energy assisted drying is a very advantageous technique for economical production. The most important advantages of this technique are that the system can be designed in many different ways in order to provide the desired characteristics. In addition, the availability of various energy storage units contributes to the availability of the system.

scholarly journals Wetting and drying performance of cross-laminated timber related to on-site moisture protections: Field measurements and hygrothermal simulations

2020 ◽  
Vol 172 ◽  
pp. 10003
Author(s):  
Lin Wang ◽  
Jieying Wang ◽  
Hua Ge
Keyword(s):  
Prolonged Exposure ◽  
Field Measurements ◽  
Butt Joint ◽  
Wood Products ◽  
Wetting And Drying ◽  
Protection Measures ◽  
Cross Laminated Timber ◽  
Grain Orientations ◽  
Group 2 ◽  
Group 1

Cross-laminated timber (CLT) panels are increasingly used in mid-rise buildings or even taller structures in North America. However, prolonged exposure to moisture during construction and in service is a durability concern for most wood products including CLT. To investigate practical solutions for reducing on-site wetting of mass timber construction, CLT specimens with a range of moisture protection measures, in six groups were tested in the backyard of FPInnovations’ Vancouver laboratory from Oct. 2017 to Jan. 2018. This study investigates the wetting and drying behaviours of the tested CLT specimens through 2-D hygrothermal simulations. The simulations are performed for base specimens (no protection measures) of group 1 (without joint or plywood spline) and group 2 (with a butt joint and plywood spline). For group 1, three data sources of material properties are used to create the models, and the data that led to the best agreement between simulations and measurement are used for creating the models of group 2. For group 2, two types of hygrothermal models are created with or without considering the differences in water absorption between the transverse and the longitudinal grain orientations. In addition, rain penetration is taken into account for the joint area. It is found that the model with considering the differences between transverse and longitudinal grain orientations shows a better agreement than that without considering such differences.

In Situ Stress Measurements during Welding Process

2017 ◽  
Vol 905 ◽  
pp. 137-142
Author(s):  
Tatsumi Hirano ◽  
Daiko Takamatsu ◽  
Kosuke Kuwabara ◽  
Shuo Yuan Zhang ◽  
Takahisa Shobu ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Phase Transformations ◽  
Welding Process ◽  
Tig Welding ◽  
Low Carbon ◽  
X Ray Diffraction ◽  
Large Area ◽  
X Ray ◽  
Compressive Stresses

Welding technologies are indispensable for fabricating various industrial structures and must be highly reliable. Since tensile residual stresses at surface after welding cause crack progress, it is important to understand how stresses built up during the welding process in order to optimize final residual stresses as reduced tensile or introduced compressive stresses. Therefore, we conducted in-situ measurements of phase transformations, stresses and temperatures during tungsten inert gas (TIG) welding to understand how stresses built up. X-ray diffraction rings were detected per 0.1 sec during TIG welding by using a large-area two-dimensional detector and the accuracy of the stress analysis was estimated to be 8 MPa using the sin2ψ technique. In this paper, we described the phase transformations of ferrite low-carbon rolled steel and the changes in stresses during TIG welding.

scholarly journals Eco-efficiency of regional development: strategical planning with DEA

2021 ◽  
Vol 114 ◽  
pp. 01011
Author(s):  
Svetlana Ratner ◽  
Andrey Kovalev
Keyword(s):  
Environmental Management ◽  
Regional Development ◽  
Production Systems ◽  
Negative Impact ◽  
Structural Heterogeneity ◽  
Comparative Assessment ◽  
Low Carbon ◽  
Protection Measures ◽  
Regional Authorities ◽  
Low Carbon Energy

Despite the implementation of the national “Ecology” project, attempts to develop low-carbon energy and transport, the implementation of “garbage reform” and other measures aimed at reducing the negative impact of the economy on the environment, the eco-efficiency of production systems in Russia remains low. In this paper, we propose a new approach to solving the problems of comparative assessment of the effectiveness of regional environmental management systems (R-EMS), taking into account the structural heterogeneity of the regional economies. The developed approach includes the simultaneous solution of two DEA tasks, one of which is formulated to assess the eco-efficiency of the region’s economy, and the other to assess the efficiency of spending funds aimed at protecting the environment in the region. As a result of solving two problems, the researcher receives a large amount of information that can be used in developing strategies for regional development. In particular, the information obtained can be used to develop measures to stimulate the activities of regional authorities in the field of environmental management and increase their responsibility for the effectiveness of environmental protection measures. The proposed approach was tested on the example of solving the problem of comparative assessment of the effectiveness of the R-EMSs in Russia in the period 2015-2019. However, the method developed by us is not tied to specific territories and can be used to conduct similar studies in other countries and regions.

scholarly journals The Role of SMEs’ Green Business Models in the Transition to a Low- Carbon Economy: Differences in Their Design and Degree of Adoption Stemming from Business Size

2018 ◽  
Author(s):  
María A. Quintás ◽  
Ana I. Martínez-Senra ◽  
Antonio Sartal
Keyword(s):  
Environmental Impact ◽  
Value Creation ◽  
Business Models ◽  
Low Carbon ◽  
Protection Measures ◽  
Environmental Practices ◽  
Low Carbon Economy ◽  
Green Business ◽  
Value Propositions ◽  
Carbon Economy

The purpose of this paper is to analyze how Green Business Models (BMs) established by small and medium enterprises (SMEs) can incorporate product and process decarbonization in their components (value proposition, creation and capture) and to what extent this incorporation is affected by SME size. We use a database comprising 1,161 observations of SMEs, 466 in 2014 and 695 in 2016. The results show that SMEs’ value propositions give an intermediate valuation to both legally required and voluntary reduction of environmental impact, irrespective of SME size and the year analyzed. Regarding value creation, SMEs adopt practically no environmental practices, and there are significant differences according to size, with more difficulties than advantages stemming from small size. The study also shows that such environmental practices are not effective in reducing carbon. This diagnosis indicates that SMEs need help from the administration if they are to play a key role in the process of transformation toward a low-carbon economy. Legislative actions involving harsher environmental protection measures might help shape value propositions that place greater importance on reducing environmental impact, whereas training actions on available environmental techniques, promotion of research on how to adapt such techniques to SMEs and the development of specific practices for SMEs might enhance environmental value creation and capture in their BMs.

scholarly journals GEOTURISMO NO NATURAL BRIDGE CAVERNS, TEXAS, ESTADOS UNIDOS DA AMÉRICA

2019 ◽  
Vol 5 (18) ◽  
pp. 12110
Author(s):  
Claudio Silva Porto ◽  
Luiz Eduardo Panisset Travassos
Keyword(s):  
Natural Resources ◽  
Field Study ◽  
Environmental Degradation ◽  
Geological Heritage ◽  
Environment Interaction ◽  
Large Area ◽  
Human Environment ◽  
Outdoor Activities ◽  
El Sistema ◽  
Life On Earth

GEOTURISM AT THE NATURAL BRIDGE CAVERNS, TEXAS, USAEL GEOTURISMO EM LO NATURAL BRIDGE CAVERNS, ESTADO DE TEXAS, ESTADOS UNIDOSRESUMONos últimos anos, vêm-se aumentando o número novas propostas de prevenção à degradação do meio ambiente, com o objetivo de conservar os recursos naturais, como forma de suporte à vida na Terra. O geoturismo pode ser considerado um instrumento pertinente na valorização e divulgação da geodiversidade, bem como da conservação do patrimônio geológico. O presente estudo teve como objetivo mostrar a utilização do geoturismo do Natural Bridge Caverns, no Estado do Texas – USA. A pesquisa foi realizada através de estudo de campo, com a observação e registro fotográfico das atividades geoturísticas oferecidas aos visitantes, bem como a observação e registro fotográfico da infraestrutura para a recepção dos visitantes. O Natural Brigde Caverns é um parque que possui uma grande área, que é muito bem explorada. Com várias atrações e atividades ao ar livre para os turistas, consegue despertar o interesse das pessoas de todas as idades, fazendo com que os visitantes aproveitem todo o dia no parque. Desde a chegada ao parque, o turista é conscientizado sobre a importância da preservação da natureza e de da interação homem-meio ambiente. O sistema organizacional do Natural Bridge Caverns pode servir de modelo para parques brasileiros que possuem cavernas, para que utilizem todo o seu potencial geoturístico de forma sustentável, gerando receitas e colocando os visitantes perto das belezas naturais do Brasil.Palavras-chave: Geoturismo; Cavernas; Meio Ambiente.ABSTRACTIn recent years, the number of new proposals for the prevention of environmental degradation has been increasing, aiming to conserve natural resources, as a way of supporting life on earth. Geotourism can be considered a relevant instrument in the appreciation and dissemination of geodiversity, as well as the conservation of geological heritage. The present study aimed to show the use of geotourism in Natural Bridge Caverns, in the State of Texas - USA. The research was carried out through a field study, with the observation and photographic record of the geotourism activities offered to the visitors, as well as the observation and photographic registration of the infrastructure for the reception of the visitors. The Natural Bridge Caverns is a park that has a large area, which is very well explored. With many attractions and outdoor activities for tourists, it catches the interest of people of all ages, making visitors enjoy all day in the park. From the arrival in the park, the tourist is made aware of the importance of the preservation of nature and the human-environment interaction. The Natural Bridge Caverns organisational system can serve as a model for Brazilian parks that have caves that utilise its geotouristic potential in a sustainable way, generating revenues and placing visitors close to Brazil's natural beauties.Keywords: Geotourism; Caves; Environment.RESUMENEn los últimos años, el número de nuevas propuestas para la prevención de la degradación ambiental ha ido en aumento, con el objetivo de conservar los recursos naturales, como una forma de apoyar la vida en la tierra. El geoturismo puede considerarse un instrumento relevante en la apreciación y difusión de la geodiversidad, así como en la conservación del patrimonio geológico. Este estudio tuvo como objetivo mostrar el uso del geoturismo en Natural Bridge Caverns, en el estado de Texas, EE. UU. La investigación se realizó a través de un estudio de campo, con la observación y el registro fotográfico de las actividades geoturísticas ofrecidas a los visitantes, así como la observación y el registro fotográfico de la infraestructura para la recepción de visitantes. Natural Brigde Caverns es un parque que tiene una gran área, que está muy bien explorada. Con numerosas atracciones y actividades al aire libre para turistas, puede despertar el interés de personas de todas las edades, haciendo que los visitantes disfruten todo el día en el parque. Desde su llegada al parque, los turistas son conscientes de la importancia de la preservación de la naturaleza y la interacción humano-ambiental. El sistema organizativo de Natural Bridge Caverns puede servir como modelo para los parques de cuevas brasileños que utilizan todo su potencial de geoturismo de manera sostenible, generando ingresos y acercando a los visitantes a la belleza natural de Brasil.Palabra clave: Geoturismo; Cuevas; Ambiente.

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