The adsorption of hexavalent chromium by preparing activated carbon from date seeds with zinc chloride as chemical activator and granular date seeds was studied in a batch system. The characteristics of date seeds and prepared activated carbon (ZAC) were determined and found to have a surface area 500.01 m2/g and 1050.01 m2/g , respectively and iodine number of 485.78 mg/g and 1012.91 mg/g, respectively. The effects of PH value (2-12), initial sorbate concentration(50-450mg/L), adsorbent weight (0.004-0.036g) and contact time (30-150 min) on the adsorption process were studied . For Cr(VI) adsorption on ZAC, at 120 min time contact, pH solution 2 and 0.02 adsorbent weight will achieve an amount of 35.6 mg/g adsorbed . While when use date seeds as adsorbent , conditions of 3 solution pH, 0.02 absorbent weight , and 120 contact time gave 26.49 mg/g adsorbed amount. Using both Langmuir, Freundlich and Sips models were explain the dsorption isotherms. It declare that the Sips model fits well with the experimental data with a maximum Cr( VI) adsorption capacity for (ZAC) and granular date stone 233.493 and 208.055 mg/g, respectively . The kinetics data which obtained at different initial Cr(VI) concentrations were examined by using pseudo-first-order, pseudo-second-order, and intra-particle diffusion models . The result gained showed that the second-order model was only describing well the empirical kinetics data of both (ZAC) and granular date seeds. It was noticed that the granular date seeds has adsorption performance lower than the (ZAC).
After the persistence of the British policy of oppression and control over the American colonies and the attempts to obliterate the identity of their inhabitants, the colonies worked on moving forward towards achieving independence, and Virginia was the first to initiate the development of the new government frameworks, through George Mason in drafting the Virginia Bill of Rights in 1776, which expressed the philosophy of the era Enlightenment and independent revolutionary thought, which called for equality and natural rights for individuals and the need for a free popular government that works for the common good.
United Arab of Emirates made efforts in developing workforce in the field of nuclear energy that it had a chance to attract specialized of this field that it reflect growth in every field of life through which it take special procedures to face casas as fokoshima .the state had started to apply the UAE peaceful nuclear program by opening (Baraka)station in 2010 as to be the first in the Arab world to aim to enhance and diversification energy sources of electricity there in addition to enhance the state’s efforts to achieve economic refreshing and environmental protect.
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One of the most powerful tools for any stellar dynamics is the N-body simulation. In an N-body simulation the motion of N particles is followed under their mutual gravitational attraction. In this paper the gravitational N-body simulation is described to investigate Newtonian and non- Newtonian (modified Newtonian dynamics) interaction between the stars of spiral galaxies. It is shown that standard Newtonian interaction requires dark matter to produce the flat rotational curves of the systems under consideration, while modified Newtonian dynamics (MOND) theorem provides a flat rotational curve and gives a good agreement with the observed rotation cu |
The amino thiadiazole [I] on treatment with aromatic aldehydes yielded Schiff bases [IIa-c], which cyclized to thiazolidinone [IIIa-c] derivatives by reaction with thioglycolic acid. Reaction of carbon disulfide and methyl iodide with [I] gavedithiomethyl [IV] which on treatment with o-phenylenediamine gave the condensed N-Imidazolythiadiazolylamine [V], However, reaction of [I] with phenylisocyanate and phenylisothiocyanate afforded the carbamideand carbothiamide derivatives [VI. VII] ac. The structure of these compounds was characterized from their melting point, FTIR spectroscopy and elementalanalysis
In this work the fabrication and characterization of poly(3-hexylthiophene) P3HT-metallic nanoparticles (Ag, Al). Pulsed Laser Ablation (PLA) technique was used to synthesis the nanoparticles in liquid. The Fourier Transformer Infrared (FTIR) for all samples indicate the chemical interaction between the polymer and the nanoparticles. Scanning Electron Microscopic (SEM) analysis showed the particle size for P3HT-AgNps samples between 44.50 nanometers as well the spherical structure. While for P3HT-AlNps samples was flakes shape. Energy Dispersive X-ray (EDX) spectra show the existing of amount of metallic nanoparticles.
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Itraconazole (ITZ) is an antifungal drug (BCSII) used for the treatment of local and systemic fungal infections. Furthermore, ITZ used as an antifungal prophylaxis for immunocompromised patients.
The objective of the study is to overcome the two problems of low and pH dependent solubility of ITZ by its preparation as floating microparticles.
Firstly, pH-dependent floating microparticles were prepared using oil in water solvent evaporation method, from which the best one (F7) selected as a best pH-dependent formula with composition of ITZ (200mg),EC (800mg), HPMC 15cps (200mg) and safflower oil (2ml) .Then, F7 was compared with the selected Relatively pH-independent ITZ floating microparticles formula wit
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This research studies the conflict issue regarding climate rapid change as a fact which occupied scientists and specialists alike, who research in this particular field, especially in recent years and how this matter has been dealt with according to real and in fictional structures via films and TV.
The researcher dealt with two researches in this study :
The first : climate extremes, human and drama rituals.
The second : realistic and imaginary construction in the cinematographic medium.
The study is based on the analysis of the film "GeoStorm", which focuses on the issue of global natural storms and the dangerous weather phenomena that threaten our planet as a result of neglect and tampering
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In this paper, a single-phase boost type ac-dc converter with power factor correction (PFC) technique is designed and implemented. A current mode control at a constant switching frequency is used as a control strategy for PFC converter. The PFC converter is a single-stage singleswitch boost converter that uses a current shaping technique to reshape the non-sinusoidal input current drawn by the bulky capacitor in the conventional rectifier. This technique should provide an input current with almost free-harmonics, comply with the IEC61000-3-2 limits, and a system operates with near unity power factor. The other function of the boost converter that should be
accomplished is to provide a regulated DC output voltage. The complete designed
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Internet of Things (IoT) is one of the newest matters in both industry and academia of the communication engineering world. On the other hand, wireless mesh networks, a network topology that has been debate for decades that haven’t been put into use in great scale, can make a transformation when it arises to the network in the IoT world nowadays. A Mesh IoT network is a local network architecture in which linked devices cooperate and route data using a specified protocol. Typically, IoT devices exchange sensor data by connecting to an IoT gateway. However, there are certain limitations if it involves to large number of sensors and the data that should be received is difficult to analyze. The aim of the work here is to implement a self-
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