This paper describes DC motor speed control based on optimal Linear Quadratic Regulator (LQR) technique. Controller's objective is to maintain the speed of rotation of the motor shaft with a particular step response.The controller is modeled in MATLAB environment, the simulation results show that the proposed controller gives better performance and less settling time when compared with the traditional PID controller.
Activated carbon prepared from date stones by chemical activation with ferric chloride (FAC) was used an adsorbent to remove phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) from aqueous solutions. The influence of process variables represented by solution pH value (2-12), adsorbent to adsorbate weight ratio (0.2-1.8), and contact time (30-150 min) on removal percentage and adsorbed amount of Ph and PNPh onto FAC was studied. For PNPh adsorption,( 97.43 %) maximum removal percentage and (48.71 mg/g) adsorbed amount was achieved at (5) solution pH,( 1) adsorbent to adsorbate weight ratio, and (90 min) contact time. While for Ph adsorption, at (4) solution pH, (1.4) absorbent to adsorbate weight ratio, and (120 min) contact
... Show MoreThis article includes designed and synthesized for bent-shaped liquid crystal molecules starting from 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of chloroacetylchloride in N, N-dimethyl formamide (DMF) and triethylamine (TEA) to product compound [I] ,then reacted the later compound with two moles of 4-hydroxybenzonitrile to yield nitrile compound [II]. Likewise, reaction 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of ethylchloroacetate with fused sodium acetate in ethanol to create an ester compound [III], and then the later compound was reacted with two moles of hydrazine hydrate in ethanol to obtained hydrazide acid compound [IV]. After that, the compound [IV] reacted with two moles of ethyl acetoacetate in
... Show MoreThis study expands the state of the art in studies that assess torsional retrofit of reinforced concrete (RC) multi-cell box girders with carbon fiber reinforced polymer (CFRP) strips. The torsional behavior of non-damaged and pre-damaged RC multi-cell box girder specimens externally retrofitted by CFRP strips was investigated through a series of laboratory experiments. It was found that retrofitting the pre-damaged specimens with CFRP strips increased the ultimate torsional capacity by more than 50% as compared to the un-damaged specimens subjected to equivalent retrofitting. This indicated that the retrofit has been less effective for the girder specimen that did not develop distortion beforehand as a result of pre-loading. From
... Show MoreIn this study, biodiesel was prepared from chicken fat via a transesterification reaction using Mussel shells as a catalyst. Pretreatment of chicken fat was carried out using non‐catalytic esterification to reduce the free fatty acid content from 36.28 to 0.96 mg KOH/g oil using an ethanol/ fat mole ratio equal to 115:1. In the transesterification reaction, the studied variables were methanol: oil mole ratio in the range of (6:1 ‐ 30:1), catalyst loading in the range of (9‐15) wt%, reaction temperature (55‐75 °C), and reaction time (1‐7) h. The heterogeneous alkaline catalyst was greenly synthesized from waste mussel shells throughout a calcin
The aims of study is to detect the inhibitory effect of Saccharomyces boulardii and Lactobacillus acidophilus on Escherichia coli that has been isolated from recurrent urinary tract infection in women. The sensitivity of E.coli isolates to antibiotics had been studied and the most resistant E.coli isolate to antibiotics had been studied .The cup assay was used on nutrient agar and Muller-Hinton agar to detect the inhibitory activity for each S.boulardii yeast grown on YEGP media and L.acidophilus grown on MRS media in which the result showed a high inhibition activity for each of them .Also in this study the adhesion property of E.coli had been evaluated in the presence of S.boulardii at concentration of 1×109 and L.acidophilus at conc
... Show More The reaction of L-ascorbic acid with the tirchloroacetic acid in the presence of potassium hydroxide gave new product Bis[O,O-2,3;O,O-5,6(chlorocarboxylicmethyliden)]Lascorbic acid (H2L) which was isolated and characterized by 1H,13C-NMR, elemental analysis (C,H,N), UV-Visible and Fourier Transform Infrared (FTIR). The complexes of the ligand (H2L) with metal ions, M+2= (Cu, Co, Ni, Cd and Hg) were synthesized and characterized by FTIR, UV-Visible, molar conductance, atomic absorption, magnetic susceptibility and the molar ratio. The analysis evidence showed the binding of the metal ions with (H2L) through the bicarboxylato group manner resulting in six-coordinated metal ion. The TLC for (H2L) and complexes showed one spot for eac
... Show MoreThe research aimed to determine the role of the agricultural extension in educating farmers about the legislation on the protection of the rural environment from pollution with chemical pesticides working in the Department of Agricultural Extension and Training and the Department of Agricultural Extension in the directorates of agriculture of Najaf and Qadisiyah, and to determine the role of the agricultural extension in the axis of farmers' use of the correct methods to protect the rural environment from pollution with chemical pesticides and the axis of the reasons that lead farmers to pollute the rural environment with chemical pesticides, and to achieve the objectives of this research prepared A questionnaire in the light of rev
... Show MoreBackground: Appreciation of the crucial role of risk factors in the development of coronary artery disease (CAD) is one of the most significant advances in the understanding of this important disease. Extensive epidemiological research has established cigarette smoking, diabetes, hyperlipidemia, and hypertension as independent risk factors for CADObjective: To determine the prevalence of the 4 conventional risk factors(cigarette smoking, diabetes, hyperlipidemia, and hypertension) among patients with CAD and to determine the correlation of Thrombolysis in Myocardial Infarction (TIMI) risk score with the extent of coronary artery disease (CAD) in patients with unstable angina /non ST elevation myocardial infarction (UA/NSTEMI).Methods: We
... Show MoreAbstract: Iatrogenic furcal root perforations are serious complications during dental treatment. This study was aimed to compare the sealing ability of new bioceramic root repair material TotalFill® with the other perforation repair materials (GIC, MTA and Biodentine) using a dye- extraction method.Materials and Methods: Forty extracted, human mandibular molars with non-fused well developed root were collected. Artificial perforations were made from the external surface of the teeth. Then the teeth were randomly divided into 4 experimental groups (n= 10) according to the type of repair material used in this study; Medifil glass ionomercement, TotalFill® bioceramic root repair material, BiodentineTM and MTA Plus. The specimens were then im
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