scholarly journals Optimum selection of zinc-coated cable trunking systems for electrical installations based on atmospheric corrosion prediction

2018 ◽  
Vol 1 (2) ◽  
pp. 5-19
Keyword(s):  
Atmospheric Corrosion ◽  
Environmental Parameters ◽  
First Year ◽  
Logarithmic Function ◽  
Atmospheric Conditions ◽  
Optimum Selection ◽  
Selection Of

The study presents a methodology for the optimum selection of the most suitable zinc-based coatings in metallic trunking systems to fulfill the requirements related to atmospheric corrosion resistance. The current methodologies are based on heuristic procedures that do not consider the influence of the in situ atmospheric conditions, which are the main cause of most of the corrosion problems. The effect of corrosion over time is generally estimated using a logarithmic function, which depends on corrosion during the first year of exposure, as well as on environmental parameters (e.g. temperature, humidity, pollutants, etc.). Different mathematical models for the prediction of corrosion during the first year of exposure were analyzed. Ten of these models were selected and compared with actual tests determining the model that best fitted the actual values. From this first-year corrosion value, the long-term corrosion function was calculated for each relevant commercial coating. Finally, a case study was analyzed by means of the proposed methodology. The results show the importance of the corrosion function and its influence in the selection of the coating to minimize costs.

scholarly journals ENVIRONMENTAL POLLUTION BY WASTEWATER FROM BROWN COAL PROCESSING ¬ A REMEDIATION CASE STUDY IN GERMANY

2014 ◽  
Vol 22 (1) ◽  
pp. 71-83 ◽  
Author(s):  
Arndt Wiessner ◽  
Jochen A. Müller ◽  
Peter Kuschk ◽  
Uwe Kappelmeyer ◽  
Matthias Kästner ◽  
...  
Keyword(s):  
Environmental Pollution ◽  
Large Scale ◽  
Pilot Scale ◽  
Wastewater Disposal ◽  
Interdisciplinary Approaches ◽  
Phenolic Wastewater ◽  
Term Monitoring

The large scale of the contamination by the former carbo-chemical industry in Germany requires new and often interdisciplinary approaches for performing an economically sustainable remediation. For example, a highly toxic and dark-colored phenolic wastewater from a lignite pyrolysis factory was filled into a former open-cast pit, forming a large wastewater disposal pond. This caused an extensive environmental pollution, calling for an ecologically and economically acceptable strategy for remediation. Laboratory-scale investigations and pilot-scale tests were carried out. The result was the development of a strategy for an implementation of full-scale enhanced in situ natural attenuation on the basis of separate habitats in a meromictic pond. Long-term monitoring of the chemical and biological dynamics of the pond demonstrates the metamorphosis of a former highly polluted industrial waste deposition into a nature-integrated ecosystem with reduced danger for the environment, and confirmed the strategy for the chosen remediation management.

scholarly journals Strategic selection of an optimal sorbent mixture for in-situ remediation of heavy metal contaminated sediments: Framework and case study

2012 ◽  
Vol 105 ◽  
pp. 1-11 ◽  
Author(s):  
Y.W. Chiang ◽  
R.M. Santos ◽  
K. Ghyselbrecht ◽  
V. Cappuyns ◽  
J.A. Martens ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Contaminated Sediments ◽  
In Situ Remediation ◽  
Selection Of

scholarly journals Optimum selection intensities in artificial selection programmes: an experimental evaluation

1977 ◽  
Vol 30 (2) ◽  
pp. 115-119 ◽  
Author(s):  
R. Frankham
Keyword(s):  
Experimental Evaluation ◽  
Selection Intensity ◽  
Effective Population ◽  
Term Selection ◽  
Optimum Selection ◽  
Selection For ◽  
Selection Intensities ◽  
Selection Of ◽  
Better Than

SUMMARYAn experimental evaluation of Robertson's (1970) theory concerning optimum intensities of selection for selection of varying durations has been carried out using published results from a long term selection study in Drosophila. Agreement of predicted rankings of treatments with expectations was excellent for low values of t/T (generations/total number scored) but poor for larger values of t/T. This was due to the 20% selection intensity treatments responding worse than expected and the 40% treatments relatively better than expected. Several possible reasons for the discrepancies exist but the most likely explanation is considered to be the greater reduction in effective population size due to selection in treatments with more intense selection.

Selection of indicator species for State of the Environment reporting: A case study from New Zealand

2010 ◽  
Vol 16 (2) ◽  
pp. 76 ◽  
Author(s):  
Joanne M. Hoare ◽  
Colin F. J. O’Donnell ◽  
Elaine F. Wright
Keyword(s):  
New Zealand ◽  
Indicator Species ◽  
Species Concepts ◽  
Monitoring Data ◽  
Environmental Reporting ◽  
Environmental Attributes ◽  
State Of The Environment ◽  
Selection Of

Indicator species approaches are widely used in conservation as a shortcut to measuring attributes of species and ecosystems. A variety of indicator species concepts are in use and are applicable to a range of situations. Indicator species are increasingly being used in environmental reporting to evaluate trends in environmental attributes quantitatively. We use the most recent State of the Environment report from New Zealand as a case study to evaluate: (1) how indicator species concepts are being applied to environmental reporting and (2) the selection of individual species as indicators. At present indicator species used in environmental reporting in New Zealand reflect biases in national monitoring data towards forest-dwelling, terrestrial vertebrates that are vulnerable to predation by introduced mammals. Scientific literature generally supports links between selected taxa and the aspect of ecosystem health they are purported to indicate, but their roles as long-term indicators of environmental health have yet to be evaluated. A primary goal of State of the Environment reporting is to set a benchmark against which environmental outcomes can be monitored over time; thus it is recognized that taxa reported should represent a broader range of environmental attributes. However, selection of taxa for environmental reporting is severely constrained by limited national species monitoring data. A strategic approach to national measurement, storage and analysis of long-term monitoring data is required to support selection of representative species for environmental reporting. We support current initiatives to select taxa for future measurement and reporting in an objective, transparent manner and recommend that they encompass representation of: (1) taxonomic diversity, (2) ecosystem types, (3) key environmental pressures and (4) threat status.

Atmospheric corrosion modeling

2014 ◽  
Vol 32 (3-4) ◽  
pp. 73-100 ◽  
Author(s):  
Hans Simillion ◽  
Olga Dolgikh ◽  
Herman Terryn ◽  
Johan Deconinck
Keyword(s):  
Structural Design ◽  
Atmospheric Corrosion ◽  
Historical Data ◽  
Material Selection ◽  
Environmental Parameters ◽  
Atmospheric Conditions ◽  
Porous Layers ◽  
The Past ◽  
Microscopic Models ◽  
Wide Range

AbstractA better understanding of corrosion processes during the last years is leading to an increased demand for numerical corrosion models. Corrosion models become increasingly relevant toward simulations, lifetime predictions, and the optimization of corrosion prevention. Also, the improvements in computational power and capacity give rise to an increased number of research projects in this field. Totally different modeling approaches are applied to a wide range of different corrosion processes. This leads to a dispersion of information in the literature. The aim of this paper is to give an overview of the present approaches in atmospheric corrosion modeling. In the past, atmospheric corrosion has been modeled based on empirical, historical data. These models provide fitted functions of the corrosion rate or damage as a function of time for different environmental parameters. These methods give no or little information about the underlying physicochemical phenomena that determine the corrosion processes. During the last decade, more and more work has been done on causal approaches. Therefore, the focus will be on these recent advances in atmospheric corrosion modeling. The links will be made to the microscopic models of isolated corrosion phenomena. The examples are crevice corrosion, corrosion under porous layers, and the modeling of local electrochemical methods. Also, some more general, macroscopic approaches will be discussed. These macroscopic approaches will be compared to each other and positioned into the scope of multiscale modeling. The first goal of atmospheric corrosion modeling is to provide tools in the understanding and quantification of the processes under the influence of external atmospheric conditions. These models could reduce the current corrosion assessment methods that essentially rely on empirical models. On a longer term, modeling would aid in optimizing the material selection, structural design, and maintenance management.

scholarly journals Measurement report: Changing characteristics of atmospheric CH<sub>4</sub> in the Tibetan Plateau: records from 1994 to 2019 at the Mount Waliguan station

2021 ◽  
Vol 21 (1) ◽  
pp. 393-413
Author(s):  
Shuo Liu ◽  
Shuangxi Fang ◽  
Peng Liu ◽  
Miao Liang ◽  
Minrui Guo ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
The Tibetan Plateau ◽  
Atmospheric Methane ◽  
Continuous Increase ◽  
Northern India ◽  
Source Regions ◽  
City Regions

Abstract. A 26-year, long-term record of atmospheric methane (CH4) measured in situ at the Mount Waliguan (WLG) station, the only World Meteorological Organization (WMO) and Global Atmosphere Watch (GAW) global station in inland Eurasia, is presented. Overall, a nearly continuous increase in atmospheric CH4 was observed at WLG, with a yearly growth rate of 5.1±0.1 parts per billion (ppb) per year during 1994–2019, except for some particular periods with near-zero or negative values, e.g., 1999–2000 and 2004–2006. The average CH4 mole fraction was only 1799.0±0.4 ppb in 1994 but increased to about 133 ppb and reached a historic level of 1932.0±0.1 ppb in 2019. The case study in the Tibetan Plateau showed that the atmospheric CH4 increased rapidly. During some special periods, it is even larger than that of city regions (e.g., 6.7±0.2 ppb yr−1 in 2003–2007). Generally, the characteristics of CH4 varied in different observing periods as follows: (i) the diurnal cycle has become apparent and the amplitudes of the diurnal or seasonal cycles increased over time; (ii) the wind sectors with elevated CH4 mole fractions switched from ENE-E-ESE-SE-SSE sectors (wind directions) in early periods to NNE-NE-ENE-E sectors in later years; (iii) the area of source regions increased as the years progressed, and strong sources shifted from northeast (city regions) to southwest (northern India); and (iv) the annual growth rates in recent years (e.g., 2008–2019) were significantly larger than those in the early periods (e.g., 1994–2007).

scholarly journals The Evaluation of a Risk Degree for the Process of a Brown Coal Spontaneous Ignition on Dumps with Using of Modern Numeric Methods

2018 ◽  
Vol 26 (2) ◽  
pp. 71-75
Author(s):  
Petr Klouda ◽  
Vlastimil Moni ◽  
Michal Řehoř ◽  
Jan Blata ◽  
František Helebrant
Keyword(s):  
Brown Coal ◽  
Barometric Pressure ◽  
Spontaneous Ignition ◽  
Atmospheric Conditions ◽  
Database Analysis ◽  
Chemical Factors ◽  
Risk Degree ◽  
Physical And Chemical

Abstract The article is a summary of information about evaluation of a risk degree for a brown coal spontaneous ignition which is realized on the base of a database analysis of information about the development of stative quantities and desorbated gases in the stored bodies of the brown coal. The data were gained from the long term complex measurements which were realized at chosen companies during the coal mining in the previous parts of the project. In the last part of the project, we examined results of temperature models from thermographs with results of gasses and coal samples from the mines. Then, the influence of atmospheric conditions (insolation, water downfall, changes of barometric pressure etc.), the influence of coal mass degradation, the influence of physical and chemical factors, and the influence of other defective factors on the process of the coal spontaneous ignition. The gasmetry was assess with gas in-situ samples and laboratory gas models of indicative gasses for the spontaneous ignition, which were taken from the method of the thermic oxidation with the aim of the correlation finding for an epicentre of temperature within the spontaneous ignition.

scholarly journals Assessing the efficiency of a “buried wall” barrier in the establishment of near-surface long-term storage and disposal facilities for RW

2021 ◽  
Vol 14 (1) ◽  
pp. 96-105
Author(s):  
V. V. Suskin ◽  
◽  
I. V. Kapyrin ◽  
F. V. Grigorev ◽  
◽  
...  
Keyword(s):  
Near Surface ◽  
Transfer Processes ◽  
Long Term Storage ◽  
Mass Transfer Processes ◽  
High Degree ◽  
The Impact ◽  
Term Storage

The article evaluates the impact of a “buried wall” barrier on the long-term safety during the long-term storage1 or in-situ disposal of nuclear legacy facilities, in particular, industrial reservoirs, as well as during the development of near-surface disposal facilities for radioactive waste (RWDF). For assessment purposes, filtration and mass transfer processes have been numerically modelled in the GeRa code based on a case study of a reference near-surface facility. The study explores in which way the available covering screen affects the dynamics of contaminant spread. It evaluates the sensitivity of the results to the dispersion parameter commonly characterized by a high degree of uncertainty.

scholarly journals A SMARTPHONE-BASED 3D PIPELINE FOR THE CREATIVE INDUSTRY &ndash; THE REPLICATE EU PROJECT

2017 ◽  
Vol XLII-2/W3 ◽  
pp. 535-541 ◽  
Author(s):  
E. Nocerino ◽  
F. Lago ◽  
D. Morabito ◽  
F. Remondino ◽  
L. Porzi ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Point Clouds ◽  
First Year ◽  
Automated Generation ◽  
Dense Point ◽  
Modelling Techniques ◽  
Eu Project ◽  
Selection Of ◽  
Made In

During the last two decades we have witnessed great improvements in ICT hardware and software technologies. Three-dimensional content is starting to become commonplace now in many applications. Although for many years 3D technologies have been used in the generation of assets by researchers and experts, nowadays these tools are starting to become commercially available to every citizen. This is especially the case for smartphones, that are powerful enough and sufficiently widespread to perform a huge variety of activities (e.g. paying, calling, communication, photography, navigation, localization, etc.), including just very recently the possibility of running 3D reconstruction pipelines. The REPLICATE project is tackling this particular issue, and it has an ambitious vision to enable ubiquitous 3D creativity via the development of tools for mobile 3D-assets generation on smartphones/tablets. This article presents the REPLICATE project’s concept and some of the ongoing activities, with particular attention being paid to advances made in the first year of work. Thus the article focuses on the system architecture definition, selection of optimal frames for 3D cloud reconstruction, automated generation of sparse and dense point clouds, mesh modelling techniques and post-processing actions. Experiments so far were concentrated on indoor objects and some simple heritage artefacts, however, in the long term we will be targeting a larger variety of scenarios and communities.

Selection of pilot areas for testing in-situ conversion/upgrading processing in lacustrine shale: a case study of Yanchang-7 member in Ordos Basin

2017 ◽  
Vol 34 (3) ◽  
pp. 221 ◽  
Author(s):  
Zhi Yang ◽  
Caineng Zou ◽  
Jinhua Fu ◽  
Lianhua Hou ◽  
Xianyang Liu ◽  
...  
Keyword(s):  
Ordos Basin ◽  
Lacustrine Shale ◽  
Selection Of
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