Asmae Khaldoun

• PhD
• Professor (Associate) at Al Akhawayn University

Desert environments are prime locations for concentrated solar power (CSP) applications due to abundant direct normal irradiance. Despite this advantage, the accumulation and adhesion of dust on CSP mirror surfaces present significant challenges to plant efficiency. This paper comprehensively explores soiling phenomena and dust adhesion mechanisms,...

Desert environments are prime locations for concentrated solar power (CSP) applications due to abundant direct normal irradiance. Despite this advantage, the accumulation and adhesion of dust on CSP mirror surfaces present significant challenges to plant efficiency. This paper comprehensively explores soiling phenomena and dust adhesion mechanisms,...

The aim of this research is to assess the impact of using recycled rubber plastic waste as additives to clay bricks in various proportions (0%, 1%, 3%, 5%, 7%, and 15%) by weight, with different grain-sizes (δ < 1 mm and 1 mm < δ < 3 mm) to evaluate their thermophysical and mechanical properties. Following the X-ray diffraction and fluorescence tes...

Aiming to reduce the resources invested in the laboratory assessment of unfired clay bricks incorporating natural wastes as additives, this paper proposes an evaluation of the surface porosity of unfired clay bricks with almond husk powder using processing of the SEM (Scanning electron microscope) images of representative cubes and its relationship...

Despite the numerous advantages introduced by renewable energy technologies to the global energy market, fossil fuels still hold the major share. Due to their greater reliability, many countries, for instance the Kingdom of Morocco, still depend heavily on fossil fuels. In fact, conventional energy sources account for more than 80% of the Moroccan...

There has been much research last decades about the feasibility of installing air-source and ground-source heat pump systems in cold areas in North America, Europe, and China. Unfortunately, not a single study has been conducted on the usage of heat pumps systems in hot steppe regions, despite the fact that hot and semi-arid (steppe) climates are m...

In the aim of enhancing unfired clay bricks’ strength, waste materials incorporation gains huge interest among researchers. In this context, various methodologies are extensively used. However, the salt concentration’s effect is poorly known. In this paper, we study, through rheological and physicomechanical investigations the influence of differen...

This study assesses the potential of waste wood sawdust, as a construction material additive, on the mechanical, thermal and physicochemical properties of compressed earth bricks. Following X-Ray Diffraction and Fluorescence analysis, the used raw clay material, retrieved from Ifrane, Morocco, was found to be of type Illite, with a prominent SiO2 c...

This paper assesses the dynamic thermal inertia performance of unfired clay bricks with dry-grass fiber additives. The used raw material was retrieved from Ifrane in Morocco. The used clay was illite with a 59.60% silicon proportion. Multiple percentages (0%, 1%, 7%, and 15%) were analyzed in this study. The dynamic thermal inertia simulation was c...

The present study aims to develop an innovative scientific methodology for adjusting the physicochemical composition of any clay soil to make it appropriate for construction applications. The realized research was carried out on unexploited clayey soil extracted from Bensmim village (Morocco). Another clay sample from "Extrabrick" brick manufactory...

With the aim of obtaining construction bricks with improved properties, this paper provides a design of unfired clay bricks based on extracted clay from Oulad Azam village in the region of Taounate in Morocco and fibers additive of saw palmetto (Chamaerops Humilis). The main objective is to study the influence of saw palmetto fibers dosage on the p...

With the aim of innovating in building materials and recycling waste materials, this work studies the feasibility of utilization of almond’s internal and external husks–hull and shell, respectively—as additives in unfired clay bricks. The used materials are provided from local resources of Ifrane, Morocco. Sixteen types of bricks and one control sp...

As living standards continue to rise, there is an increasing demand for thermal comfort in buildings, which raises energy consumption, especially in severe climates. Passive systems have received much attention since they may give the necessary level of comfort while being environmentally beneficial. The Trombe wall, a passive heating idea for cold...

Conventional air conditioners are considered the most energy-intensive components in residential and tertiary buildings. Besides high energy consumption, they are also harmful to the environment due to the emissions of hydrofluorocarbons into the atmosphere. Night sky cooling or radiative cooling is a naturally occurring phenomenon that takes advan...

In this study, the potential of using a wall made of Graphene Oxide Bricks (GOB) as a heating system is analyzed. This study explains the properties of these bricks considering the concentration of graphene oxide based on a study conducted by Wuhan Polytechnic university. The simulation in Designbuilder software shows that the heat gains in the col...

Dry grass is a widespread residue of agricultural activities in Morocco. This paper investigates the effect of incorporating this organic waste on the Physicochemical and Thermomechanical performance of unfired clay bricks. The used raw clay material used is of illite type, extracted from Bensmim in the Ifrane region. Various grass filler proportio...

Plastic wastes can be recycled and put into good use as construction material additives to improve clay bricks’ thermal, mechanical and physicochemical performances. This paper aims to design a forecasting model to predict brick samples’ properties at different plastic waste (HDPE & PET) additive percentages. This model will enable doing so at a ti...

Engineered unfired clay bricks are an ecological alternative to overcome conventional construction materials’ inconvenience. This work investigates the rheological behavior of organo-silica suspensions, made from almond husk waste and illite clay, in relation to the compressive strength of unfired clay bricks incorporating the same waste. Selected...

Many sites with high solar radiation like MENA regions face high dust loads that reduce the efficiency generation of solar plants. In this context, this paper provides an overview of dust adhesion mechanism on the surfaces of concentrated solar power (CSP) mirrors. The assessment of dust adhesion was performed on the hydrophilic/hydrophobic glasses...

The present work investigates the effect of using olive pomace bottom ash, the by-product of the clay brick industry, as an additive in the manufacture of fired clay bricks. Furthermore, it aims to improve the properties of clay bricks by using naturally available materials and also to develop an innovative way of recycling the waste resulting from...

Concentrated solar power (CSP) plants are one of the most advanced technologies in terms of generating electricity from solar energy. However, this technology is facing many issues; one of their main issues is their high consumption of water in their daily operations. In this context, the purpose of this paper is to find a new solution that can be...

Cork is an ecological, natural, and renewable additive, an excellent thermal and acoustic insulator. All these attributes encourage its use in the building sector. Adding this additive to the Earth leads to a more lightweight composite with better thermal performance than the Earth alone. Unfortunately, the mechanical performance of this composite...

This study presents the results of theoretical and experimental investigations of zinc oxide (ZnO) and aluminum-doped zinc oxide (AZO) thin films, prepared by RF magnetron sputtering. The structural, optical and morphological properties were examined, and the results show that the AZO thin films exhibit a higher optical transmittance compared to in...

This study aims at the valorization of unexploited clay from a rural village called Bensmim by investigating its potential suitability as a construction material. Two clays samples (Babmansour and Extrabrick) used in the clay brick manufacturing were also considered as a reference. The followed methodology consists of identifying the physicochemica...

Sludge disposal has major drawbacks on the environment when damping wastewater treatment sludge in landfills and estuaries. In addition to financial drawbacks manifested by the poor sludge management due to the lack of valorization regulations or investments’ encouragement. This paper analyzes the mechanical, physicochemical, and thermal properties...

This paper assesses the thermal performance of reinforced Typha-fibers unfired clay bricks. Various Typha additive proportions (0%, 1%, 3%, 7%, 15%, and 20%), by weight in a fibrous form, have been prepared for experimental testing. X-ray diffraction and fluorescence analysis showed that exploited clay is suitable for construction purposes with a p...

The aim of this study is to evaluate the suitability of recycled Typha-fibers waste as a construction material additive to unfired clay bricks. The novel approach of this paper is providing an alternative of damping Typha plants in landfills and waterways, by recycling these waste and putting them into good use as a construction material additive....

This paper assesses the effect of recycled date pits waste additive as a construction material additive to unfired clay bricks, with m Multiple waste additive proportions (0%, 1%, 3%, 7%, 15% and 20%), by weight, in terms of their physicochemical, mechanical and thermal performances. Crystalline characterization of used clay in its raw state, via X...

h i g h l i g h t s An innovative sandwich material with clay-cork composite as a core was introduced. Increasing coating layers thickness enhances sandwich material mechanical performance. Lightness and thermal properties decrease with increasing coating layers thickness. Optimal mixture both for mechanical and thermal properties was checked in th...

New sandwich material was produced using clay-granular cork composite as core material with a protective coating of plaster and cement mortar. The principal purpose of the present work is to evaluate the thermomechanical behavior of the innovative sandwich material experimentally. The effect of volume fraction of plaster and cement mortar coating o...

The main objective of this study is to investigate the effect of incorporation of wastes plastics additives in the thermal performance of unfired clay bricks. The low adhesion between the clay and polymer molecules, in general, is one of the major challenges faced while blending the two components. In this paper, an innovative brick preparation tec...

This paper presents an innovative approach for the study of the adhesion of dust particles on the surface of CSP reflector mirrors. Three types of CSP mirrors are studied, the first one is the commercial mirror used at NOOR 1 project, the second one is a CSP mirror with hydrophobic amorphous Al2O3 nano-coating and the third one is CSP mirror with h...

Developing ecofriendly houses using local, low embodied energy construction materials such as clay represents an essential step towards making houses more cost and energy efficient. Ifrane region, and particularly Bensmim counts many low to medium income families that cannot afford high heating bills. This project aims at contributing to the develo...

The main purpose of this study is to contribute to the transformation of Zaouiat Sidi Abdeslam into an ecological village. The latter will serve as a model for promoting ecological building practices and sustainable communities in the region. Minimizing energy consumptions and losses as well as enhancing the living conditions of the village inhabit...

TiO2 thin films with different thicknesses were deposited on glass substrates by using the Ion Layer Gas Reaction (Spray-ILGAR) technique at a substrate temperature of 460°. The effects of deposition time on the morphology and the optical properties of deposited anatase TiO2 thin films are studied. A wide range of characterization techniques such a...

The extreme conditions of desert locations put a lot of stress on the components of CSP systems. Solar reflectors, in particular, are sensitive to soiling and abrasion from sand and dust and might see their ability to reflect and concentrate light compromised. Whereas soiling is usually reversible with cleaning, the abrasion of the mirrors' surface...

In Concentrated Solar Power (CSP) application, top coatings are of tremendous importance as a way to protect the reflective layers form degradation and conserve the efficiency and durability of the mirrors. The choice of Al 2 O 3 as a top-protective coating for CSP reflectors is based on its high stability, hardness and transparency. In this study,...

The aim of this study is to simulate thermal properties of Bensmim clay-wool composite through using microstructure based finite element modeling. These materials have been chosen due to their low cost and local availability. Cutting edge software tools that implement finite element methods will be used in order to first generate the 3D microstruct...

In this study, potential sites for concentrated solar power (CSP) installations in Morocco are investigated based on direct normal irradiation (DNI). The DNI data of four Moroccan sites (Missour, Erfoud, Zagora and Tantan) were collected from different satellite databases (NASA SSE, PV GIS-Helioclim, Climate-SAF PVGIS and Solar Med Atlas). However,...

The solar reflectors used in Concentrated Solar Power (CSP) technologies are either front-surface or second-surface mirrors. The advantage of second-surface mirrors over front-surface mirrors is due to the fact that the reflective layer in second-surface mirrors is covered from the front-side by glass, which allows protection against degradation fa...

This work is a contribution to understand the thermal properties of Illite with ecological additives granular presented by cork or fiber by wool in order to use those composites in building construction, the composites are air dried. Knowing that the clay composites were studied before, a series of experimental studies confirmed by complete theoret...

Desert areas are considered to be the most suitable sites for CSP power plant installations due to their high irradiance, principally the direct normal irradiance (DNI), as well as the flat land scape and lower population densities. However, CSP reflector components are exposed to very harsh weather conditions in desert areas, such as wind storms,...

For the purpose of resisting to the hard climatic condition and so as to improve the insulation of building material in the Ben Smim Ifrane region, we proceeded in this work to develop local materials, clay is a building material very used in walls or floor in this region, The goal consists to improve the thermal properties of clay bounded with gra...

Titanium Dioxide is an important material that is used in many industrial applications such as photo-catalysis, glass-defogging, self-cleaning, waste water purification and anti-bacterial sterilization. The strong photo-catalysis of TiO2, and therefore its ability to decompose dirt and organic contaminants makes it an excellent top-protective layer...

In This paper, we have discussed one example of the third generation solar cells, called nanocrystalline dye sensitized solar cells DSSC or Gratzel cell. An extensive literature study was conducted and the results show that the Nanocrystalline dye sensitized solar cells DSSC are considered as a novel and low cost photovoltaic technology. Compared w...

This work consists on the improvement of first surface silvered thick glass mirrors. Several types of CSP mirrors based on different Physical Vapor Deposition techniques (PVD) and the presence or absence of the copper protective back layer were prepared: ([Ag Sputtered], [Ag Evaporated], [Cu Sputtered-Ag Evaporated], [Cu Evaporated-Ag Sputtered], [...

CSP reflectors are a key component for CSP technology and are characterized by their specular reflectance (SR), the degree to which a mirror is capable of transferring directed radiation to a target receiver surface. The accumulation of dust on the surface of the reflectors can decrease the ability of their mirrors in reflecting the radiation to th...

The purpose of this study is to evaluate, analyse and draw up maps of the heating and cooling degree-days (CDD) for Morocco. Data from 37 weather stations around Morocco during 10 years (2000–2009) were used. The mean heating and CDD at base temperatures of 18°C and 21°C, respectively, were presented. The effect of the geographical conditions such...

This project provides a reference on how to perform a complete thermal analysis and brings a concrete example using different tools and equations for the estimation of the heating or cooling loads of residential buildings. For this purpose, different methodologies and calculations done by auditing organisms that evaluates how efficient the building...

We study the rheology of quick clay, an unstable soil responsible for many landslides. We show that above a critical stress the material starts flowing abruptly with a very large viscosity decrease caused by the flow. This leads to avalanche behavior that accounts for the instability of quick clay soils. Reproducing landslides on a small scale in t...

We investigate the adsorption strength of some very toxic substances like lead, cadmium and mercury and sodium triphosphate, a highly environmental contaminant, on purified and homogenized fluorinated sodium montmorillonite NaFMt or “Rassoul”, and the influence on its electronic and surface-energy properties. The changes in the wettability of this...

People or animals caught in quicksand find it very hard to escape. Here we show that quicksand acts as a trap because it becomes unstable when it is forced to move--first it liquefies, and then it collapses. But a simple sinking test demonstrates that it is impossible for a human to be drawn into quicksand altogether.

Rassoul is clay extracted from Atlas Mountains in North Africa, characterized by its high capacity of adsorption and ionic exchange. The high stability of the rassoul particles suspension is closely linked to their capacity to interact by electrostatic and thermodynamic interactions within the aqueous medium. A fundamental contribution to the energ...

In this article, we describe the rheology of a condensed suspension of FNaMt particles 5w% as a function of pH, at constant ionic strength. The steady-state viscosimerty measurements showed that the yield stress increase up to an order of magnitude between pH3 and pH6, with a much slower rate of increase in the 6 to 9 pH interval. Concerning the dy...

The effect of humic acid (HA) adsorption on the hydrophilicity of two different montmorillonite samples (Na-montmorillonite, NaMt, and a Na-fluorinated Na-montmorillonite, FNaMt, or 'Rassoul') was investigated. The changes in the wettability of clays were discussed in terms of the non-electrostatic free energy of interaction between the clay partic...