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31.
The following work aims at minimizing the environmental impact of the solid wastes (ash) that is produced after the utilization
of the bituminous limestone in thermal power stations and/or retorting processes. The laboratory tests have been selected
with respect to construction needs and possible post construction conditions. Utilization of the various types of ash in the
production of lightweight concrete block has revealed optimum results. The compressive strength of various ash–glass sand
mixes has ranged between 19 and 76 kg/cm2 at 28 days. The compressive strength of ash–tuff mixes has ranged between 54 and 63 kg/cm2 at 28 days. Ultra light mixtures using ash–polyester with a density of 0.88 kg/m3 and a compressive strength of 21 kg/cm2 at 28 days are produced at normal room curing temperature without the use of ordinary Portland cement. The high alkalinity
of El-Lajjun ash is considered a disadvantage when utilized in normal concrete mixes for structural purposes. Ash only can
be mixed with aggregates to produce lean concrete for blinding purposes for use in foundations. 相似文献
32.
Hani Sewilam Heribert Nacken Roman Breuer Christiane Pyka 《Environmental Earth Sciences》2017,76(3):131
Sustainable water management is one of humanity’s most important challenges—today and in the future. Germany does not face a significant water shortage problem, but it has three main challenges: protection of water quality, ensuring public water supply and public wastewater disposal, and protecting the public and infrastructure from floods. Capacity development is a key issue to overcome the challenges of water resources in any country including Germany. Engineers, technicians, and mechanics need to upgrade their knowledge on a regular basis to deal with the complex management and rapid technological developments. In order to create efficient training schemes, the Vocational Training Working Group of Global Water Partnership (GWP), part of the GWP Capacity Development Task Force, has worked on the definition of fundamental job profiles for the Water and Sanitation Sector (WASS). To cover all technical functions of the industrial water cycle, it was necessary to identify around thirty occupations. Then, a competence-based training approach was adopted. Additionally, an assessment approach was also developed based on comparing the level of competence of the workers to a standard level of competence for each job. The RWTH Aachen University with its partners have developed another game-based approach (SeCom2.0) based on serious gaming technology to enable water professionals dealing with flood risk management to be trained on different flood situations in a virtual environment. SeCom2.0 has three main components that are connected by a database layer. In addition to the serious games component, there is a collaboration component and a learning management system. For nearly 100 members from the flood competence centre (HochwasserKompetenzCentrum) in Cologne, Germany gave input to simulate the real flooding scenarios, and the learners will have to deal with a flood scenario by protecting the city in a given time and using a given resources and tools. This work concluded that both competence-based and game-based approaches could be significantly improved by blending both approaches. This will improve the process of training; for example, the competence-based approach can be enriched by using game-based simulation by introducing the trainees to a simulation of different technologies in water utilities. This can save resources and money and enrich the training. More importantly is modifying the game-based approach using the approach of competence-based to focus on specific competencies and to make use of the competence standards in its assessment component. The first section of this introduces and categorizes water challenges in Germany. In the second and third section, the two approaches are introduced in details. The competence-based approach is introduced to the WASS while the games-based to the flood risk management. Finally, a conclusion and recommendations are illustrated. 相似文献
33.
Gerges Firas Nassif Hani Geng Xiaolong Michael Holly A. Boufadel Michel C. 《Natural Hazards》2022,111(2):1271-1299
Natural Hazards - Community resilience refers to the degree to which a community can survive and recover following a disaster. While resilience itself is well understood, decisions that would... 相似文献
34.
Hani N. Khoury 《Environmental Earth Sciences》2012,65(6):1909-1916
Quaternary travertine capping the metamorphic (cement) zones in Uleimat Quarries, central Jordan, has been precipitated from
hyperalkaline paleogroundwaters. Such waters are similar to the cement pore water and to the present day hyperalkaline seepages
(pH 12.5) in Maqarin, north Jordan. The isotopic depletions observed in Uleimat travertine, with δ13C values as low as −25.45‰, suggest that they have been precipitated during CO2 uptake by highly alkaline calcium hydroxide waters. The travertine in Uleimat Quarries indicates a long-term analog of carbonation
and remobilization of silica in cementitious barriers for radioactive waste repositories. The presence of Cr-rich smectites
and relatively high levels of Cr (4.1%), V (657 ppm), Ni (163 ppm), Zn (634 ppm) and U (34 ppm) in the green travertine and
the associated opaline silica phases suggests the use of the Uleimat travertines as analogs with the repository disturbed
zone. Smectites and silica phases are expected to be a sink for alteration products in the late stage evolution of a high
pH plume. Co-precipitation of these elements in mineral phases is of great importance to control the concentration of these
elements in groundwater. 相似文献
35.
The objective of the present study is the assessment of Jeddah ambient air quality in terms of PM2.5, and the associated lead 7 years after phasing out leaded gasoline in Saudi Arabia. Twenty‐four air samples were collected at four locations throughout Jeddah during the period from December 23, 2008 to April 6, 2009. The collected PM2.5‐samples were analyzed by ICP‐MS for determination of lead. The average atmospheric PM2.5 concentration was 50.8 µg/m3. Atmospheric PM2.5‐concentrations were higher than the 24‐h U.S. National Ambient Air Quality Standards (NAAQS) in 14 sample events. The average lead concentration for all samples was 0.07326 µg/m3. Atmospheric lead concentration was dependent on the sampling location. Concentrations at the two southern locations were higher than at the two northern locations. Southern locations had higher lead concentrations due to very high traffic density, in addition to their proximity to industrial zone. In general, the results of this study show a considerable decrease in atmospheric lead concentration 7 years after phasing out leaded gasoline. The study recommends further studies to accurately determine the current sources of atmospheric lead. 相似文献
36.
Geotechnical Risk Assessment of Mine Development Intersections with Respect to Mining Sequence 总被引:2,自引:2,他引:0
Wael Abdellah Hani S. Mitri Denis Thibodeau Lindsay Moreau-Verlaan 《Geotechnical and Geological Engineering》2014,32(3):657-671
Mine developments such as haulage drifts and their intersections with cross-cuts are the only stope access in sub-level stoping mining system. Thus, they must remain stable during their service life. Haulage drift instability could lead to serious consequences such as: production delay, damage to equipment, loss of reserves and high operational cost. The goal of this paper is the stability of mine developments with respect to mining sequence with focus on the performance of haulage drift intersection during the production plan. A case study, the #1 Shear East orebody at Vale’s Garson Mine in Sudbury Ontario will be examined in this paper. A three-dimensional, elastoplastic, finite difference code (FLAC3D) is used for this study. The extent of strength-to-stress ratio corresponds to Mohr–Coulomb strength-to-stress ratio of 1.4 is used as failure evaluation criterion. The unsatisfactory performance is reached when the extent of strength-to-stress ratio exceeds the anchorage limit of the rockbolt. Stochastic analysis; adopting point-estimate method, is then employed with the numerical modelling to tackle the inherent uncertainty associated with rockmass properties. Then, the probability of instability at various mining steps is estimated for the roof and north wall of the studied intersection. The cost of consequence models is introduced to provide an economical solution if the intersection failed, blocked or damaged. Furthermore, the geotechnical risk associated with the instability of mine development intersection is estimated using risk-indexing tool. The results are presented and categorized in terms of probability, cost of consequence and risk-index at various mining stages. 相似文献
37.
Till Heinrichs Elias Salameh Hani Khouri 《International Journal of Earth Sciences》2014,103(1):233-252
The deeply eroded Waqf as Suwwan ring structure was recently discovered to be a large impact, the first identified in the near east. Large-scale reflection seismic structure shows the impact situated high on the northeastern flank of the Jordan Uplift sloping into Wadi Sirhan Basin. If exhumation is linked to the Arabia–Eurasia collision, a likely time window for the impact event may be latest Eocene to Late Oligocene. Impact into a shallow sea seems an optional scenario. Old reflection seismic lines offer limited insight into the deep structure of the rim and part of the central uplift of the complex crater. An important structural clue is provided by a well-resolved seismic horizon of a yet tentative correlation with a Paleozoic black shale. The central gravity high is compatible with a mass surplus by the uplift of denser Paleozoic basement below the central uplift. The gravity model further indicates a ring of dense Paleozoic sediments rising from below into the ring syncline. Seismics show presumably radial synclines in the central uplift which are interpreted by centripetal constrictional flow during crater collapse. Beneath the final crater’s outer boundary, a shallow-dip normal fault zone, subtle seismic structure in uncollapsed footwall segments reveal an asymmetry of strain. The asymmetry is attributed to the cratering flow by an oblique impact directed toward NE. The finding provides independent support to an earlier suggestion of impact obliquity based on vergency of folds exposed on the central uplift. 相似文献
38.
Nezar Hammouri Hani Al-Amoush Marwan Al-Raggad Sura Harahsheh 《Arabian Journal of Geosciences》2014,7(7):2815-2829
This paper aims at mapping the potential groundwater recharge zones in the southern part of Jordan Valley (JV). This area is considered as the most important part for agricultural production in Jordan. The methodology adopted in this study is based on utilizing the open ended SLUGGER-DQL score model, which was developed by Raymond et al (2009). Geographic information systems were used in this study to build up the different layers of this model and to create the potential groundwater recharge zones. Based on the generated SLUGGER-DQL potential map, it was found that about 70.8 % of the investigated area was categorized as high potential for groundwater recharge, 18.7 % as moderate, and 10.5 % as low potential for groundwater recharge. To validate the model results, sensitivity analysis was carried out to assess the influence of each model parameter on the obtained results. Based on this analysis, it was found that the slope parameter (S) is the most sensitive parameter among SLUGGER-DQL model parameters, followed by water level in summer (L), well density (D), water quality (Q), runoff availability (R), land use/land cover, geology (GE), whereas the lowest sensitive parameter is the geology parameter (GE). Moreover, the parameters R, D, and Q show the lowest effective weights. The effective weight for each parameter was found to differ from the assigned theoretical weight by SLUGGER-DQL index model. 相似文献
39.
The purpose of this study is to include expert knowledge as one part of the modelling system and thereby offer the chance to create a productive interactive system between expert, mathematical model, ASM, and artificial neural networks (ANNs). An attempt to determine outflow‐influencing parameters in order to simulate spring flow is presented. The Bouteldja dune aquifer is fed by rains and streaming water on the sandy argillaceous relieves in the Est. The lateral passage to the gravel of the Bouteldja Plain is marked by numerous bogs that correspond to the piezometric level. These bogs have long been an environment for migratory birds and a natural reserve for many species. However, the continued exploitation of about 30 wells has negatively influenced the hydrodynamic equilibrium of the aquifer and has brought a diminution of the sources' capacity. In this study, we tried by using a hydrodynamic model and the neural network to ascertain the state of the resources and to identify the factors responsible for the decreasing flows of the three principal springs of the area (Bougles, Bourdim and Titteri) by using neural networks. The results obtained show a continued exhaustion of the reserve since 1986 with a large cone of depression. The ANNs show that the decrease in flows of the springs is not only due to the unfavourable climatic conditions, but also to the intensive exploitation of the aquifer. These results show that the groundwater reserves are decreasing over time, thus highlighting the need to take some urgent measures to stop this phenomenon. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
40.
Hani Serhal Daniel Bernard Jamal El Khattabi Bastin-Lacherez Sabine Isam Shahrour 《Environmental Geology》2009,57(7):1579-1592
Since 1975, Europe sets up its policy to limit the degradation and the pollution of the aquatic environments through 30 directives
and regulations. In the north of France, the nitrate concentrations measured in the groundwater exceed the water drinking
limit fixed at 50 mg/L by the European framework directive in the field of water (2000/60/EC). This high concentration is
due to intensive agriculture, industrialization and demographic growth. Several programs were launched in order to resolve
this situation: “Ferti-better” or the use of fertilizer in moderation and installation and amelioration of wastewater collect
and treatment systems. In order to estimate the influence of the anthropic activities on the quality of groundwater in the
“Artois-Picardy” basin, a preliminary validation on parcel and district scale were necessary. The impact of these programs
in the “Cambrai district” was evaluated using an integrated approach, which is based on the use of four numerical models:
AgriFlux, VS2DT, Modflow and MT3D. The results illustrate an improvement due to the “Ferti-Better” program initiated in 1990
and punctual degradation under urbanized areas. Predictions (2015) show a spatial evolution of nitrates concentration varying
with the thickness of unsaturated layer. The integrated model constitutes an efficient tool for predicting the evolution of
the groundwater quality. This approach is important to control the application of the new European laws in the water field. 相似文献