تهدف هذه الدراسة إلى تقييم مستويات الفلوريد في منتجات معاجين الأسنان التي تباع حاليًا في السوق الليبي. تم تحليل 30 عينة مختلفة من منتجات معاجين الأسنان (9 عينات للأطفال و21 عينة للبالغين) لتقدير تركيز الفلوريد باستخدام الطريقة الطيفية. أظهرت النتائج أن جميع عينات معاجين الأسنان المخصصة للأطفال تحتوي على مستويات فلوريد أقل من 500 جزء في المليون، وهو مناسب للأطفال. في المقابل، كان تركيز الفلوريد في 18 عينة (85.7%) من معاجين الأسنان للبالغين يتراوح بين 500 و1500 جزء في المليون، بينما تجاوزت 3 عينات (14.3%) المستوى المسموح به بتركيز أعلى من 2000 جزء في المليون. يمكن الاستنتاج أن محتوى الفلوريد في معاجين الأسنان للأطفال كان ضمن المستويات المثالية الموصى بها، في حين وُجد تباين واسع في تركيز الفلوريد في العينات الأخرى

We present a solution method for a general Riccati differential equation by imposing relationships between

the coefficients of the Riccati differential equation and explaining them through proofs and examples, we can find the

general solution to the various forms of Riccati's equation by integration directly after transforming it into a separable

differential equation.

Vortex airflow-assisted melt differential electrospinning for preparing superfine fiber yarns was proposed. This method with solvent-free exhibits a higher yield of 20 ± 5.17 m/min compared to the range of 0–5 m/min achieved by solution electrospinning with organic solvents. Simulation and high-speed photography show that the fibers are aggregated by suction airflow and twisted into yarns by vortex airflow. Polylactic acid (PLA) superfine fiber yarns exhibit fine fiber diameters ranging from 0.96 to 5.57 μm, a yarn diameter of 211.7 ± 40.8 μm, and a high tensile strength of 39.4 ± 3.12 MPa. Furthermore, these PLA melt electrospun yarns can be woven into fabric with a water contact angle of 120.1° and triboelectric voltage of 7.41 V, demonstrating their potential in self-cleaning textiles and flexible smart textiles. Moreover, this method is generally applicable to thermoplastic polymers including polyethylene …

A new record for Leptadenia arborea (Forssk.) Schweinf. is reported for the first time in the flora of Libya. This species was collected from Ariggiba region (110 km southwest Sabha city). A full description and habitat information on the plant are provided. A brief discussion about the most important traits of this species is presented.

A design of a geothermal heat pump heating, ventilating, and air conditioning system has been done for XYZ Indianapolis School by using renewable energy. Geothermal energy is one of the important energies that has proved itself in air conditioning systems all over the world. The design was classified in three points as follows. Using borehole heat exchanger (BHEs) vertical type, heat pump and all its equipment such as mechanical room, pipes, and fitting design to cover the total load of the school the results were 20 boreholes and a total flow rate of 60 gpm (3 gpm/bore) of 20 % propylene solution, and spacing 20 ft with 1.1 Hp and 6.5 in impeller size. For individual borehole design, the results were 15 boreholes and a total power consumption 1.1 kW. For the ventilation design, the peak load for heating is 42779 Btu/hr, and for cooling, it is 47779 Btu/hr. There are 4 boreholes, a 0.5 hp electric pump with a flow rate of 10 gpm a 40ft of H2O pressure drop, and a 10 hp fan integrated with a water-to-water heat pump. The total load we assumed for the heating supply in class 6 and the corridor are 10% and 25 %, respectively. The thermal resistance was calculated for each case according to the fluid flow rate. The ventilation load of the school is designed separately from the heating and cooling loads and connected to a water-water heat pump that will make the system work with high efficiency. Finally, we designed this project using Geothermal Energy, which is cleaner than conventional energy.

//

0