Application of central composite design to optimize culture conditions of chlorella vulgaris in a batch photobioreactor: An efficient modeling approach
Microalgae cultivation and their use is a promising approach for integrated CO2 biofixation, wastewater treatment and renewable energy production. To develop such an important technology, there is a need to optimize the culture conditions, maximizing CO2 consumption, degrading the nutrients present in the wastewater and maximise the microalgae biomass production. [...]
Kinetics of the pyrolysis of cobalt-impregnated sesame stalk biomass
In this work, thermogravimetric analysis of sesame biomass samples was conducted in inert atmosphere at heating rate of 10 °C/min in the temperature range 30–1000 °C. Kinetic parameters were calculated applying the Coats-Redfern (CR) method. TG/DTG of sesame biomass showed that pyrolysis mainly occurred in the temperature range 205–412 °C. Therefore, the biomass [...]
Pyrolysis of polystyrene: The influence of commercially available oxides as catalysts
Summary: In this study four catalysts (ƴ –Alumina, α- Alumina, silica gel and silica ppt) with different physicochemical characteristics were tested for the pyrolysis of polystyrene (PS) under inert atmosphere in the temperature range 200-650 °C at heating rate 5 °C/min. The silica gel a mesoporous catalyst, with a greater [...]
Introduction to nanosensors
Sensors are devices that detect a physical, chemical, or biological stimulus and give a response in the form of a measurable signal. The increasing number of applications for sensing technologies has increased the need for the development of a variety of new sensors with far better performance. Nanoparticles are at [...]
Multilayered ZnO/TiO2 nanostructures as efficient corrosion protection for stainless steel 304
ZnO/TiO2 coatings are deposited onto 304 stainless steel substrates by using sol-gel dip-coating technique followed by subsequent annealing. X-ray diffraction analysis reveals nanocrystalline ZnO and TiO2 phases for all multilayered films except 1ZnO/1TiO2 with amorphous nature. Optical microscopy images show the presence of some streaks, holes, scratches and micro-traces, meanwhile [...]
Effect of Er doping on the microstructural, optical, and photocatalytic activity of TiO2 thin films
Nanostructured Er3+ doped TiO2 thin films are deposited onto glass substrate via sol-gel dip-coating followed by calcination at 450 °C for 1 h. X-ray diffraction analysis confirms that the films crystallized within single tetragonal anatase phase. Atomic force microscopy observations reveal that the surface of pure TiO2 is characterized by [...]
Evaluating the performance of a daylighting traditional device, the Mashrabiya, in clear sky conditions: Case study of a traditional Bahraini house
The mashrabiya is used in traditional Islamic architecture to provide visual privacy, reduce the glare from direct sunlight, and allow natural ventilation. Traditional Bahraini houses were designed with specific features and characteristics to cater to the cultural and religious needs of the occupants and the bio-climatic conditions. This study has [...]
Photoelectrochemical nanosensors
Electrochemical and optical sensors are useful probes for the detection of medically relevant analytes. For more sensitive drug detection, the properties of both of these devices are combined into a photoelectrochemical sensor (PECS). The photocatalytically generated current in a photoelectrochemical sensor is enhanced by different combinations of organic and inorganic [...]
Streets are forever: thermal coefficient of street orientation as a strategy to develop cooler street networks in hot climates
Maximizing the annual season of street comfort in hot climates requires synergies between all planning and design features. The absence of such combination compromises comfort and planning goals, like increasing walkability. Street orientation is both a determinant of its solar intake and a design feature that outlasts all others. In [...]
Rethinking contemporary domestic space organization: Patterns of alterations in Bahrain subsidized housing projects
Current housing design guidelines in Bahrain focus on purely functional and energy efficiency factors. The Ministry of Housing in Bahrain (MOH) has been providing subsidized houses to its citizens since 1970’s. In 2010, according to the MOH, the demand for new housing units had reached the 50,000 mark and the [...]