The paper presents research results of the vibration transmitted from the steering wheel of the tractor with a 2-wheel drive to the driver’s hands. The vibration measurements were carried out on the tractor randomly chosen from the collage of agriculture / university of Baghdad. Before testing the tractor was examined and adjusted following the producer’s recommendations. The vibration levels were measured during the operation tillage at idling and at full load .The field was 31.7 m above level sea. Soil was treated at soil constant moisture (17-20 %) with depth of plowing (17 cm). During operation the weather temperature was measured (15 C) and humidity was ( 27 % ) The vibration level on the steering wheel was measured and analyzed .The frequency-weighted acceleration(RMS) , given in , was calculated. The vibration total value was defined as the root-mean-square of the three component value
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In this study, composite materials were prepared using unsaturated polyester resin as binder with two types of fillers (sawdust and chopped reeds). The molding method is used to prepare sheets of UPE / sawdust composite and UPE / chopped reeds composite. The mechanical properties were studied including flexural strength and Young's modulus for the samples at normal conditions (N.C). The Commercial wood, UPE and its composite samples were immersed in water for about 30 days to find the weight gain (Mt%) of water for the samples, also to find the effect of water on their flexural strength and Young's modulus. The results showed that the samples of UPE / chopped reeds composite gained highest values of flexural strength (24.
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Spray pyrolysis technique (SPT) is employed to synthesize cadmium oxide nanostructure with 3% and 5% Cobalt concentrations. Films are deposited on a glass substrate at 350 ᵒC with 150 nm thickness. The XRD analysis revealed a polycrystalline nature with cubic structure and (111) preferred orientation. Structural parameters represent lattice spacing, crystallite size, lattice parameter and dislocation density. Homogeneous surfaces and regular distribution of atoms were showed by atomic force microscope (AFM) with 1.03 nm average roughness and 1.22 nm root mean square roughness. Optical properties illustrated a high transmittance more than 85% in the range of visible spectrum and decreased with Co concentration increasing. The absorption
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The present research has investigated the effect of microwave energy on improving the flow properties of heavy crude oil. The fragmentation of crude oil molecules was carried out with and without using 1 and 10 wt. % concentration of various types of H-donors like tetralin, cyclohexane, and naphtha. Microwave power of 320, 385, and 540 W and radiation time 1-9 min, and temperature were studied. The kinematic viscosity and asphaltene content were measured for evaluation the improving of heavy crude oil.
Results show that viscosity of crude oil decreased with increase H-donor concentration, a maximum percentage of viscosity reduction was10.63 % for tetralin at 6 min radiation time, while 8.67%, and 7.34% for cycl
... Show MoreThe inhibitory action of four lactobacilli isolates Lactobacillus bulgaricus, L. acidophilus, L. plantarum and L. fermentum, isolated from four different samples; yoghurt, vinegar, saliva and vagina respectively, on Escherichia coli and Staphylococcus aureus adhesion to uroepithelial cells were investigated. Results showed that all Lactobacillus isolates or their supernatant were able to reduce the number of the uropathogens attached to uroepithelial cells. However, inhibition level of lactobacilli cells was higher than their supernatant. Nevertheless, the human indigenous lactobacilli (L. fermentum and L. plantarum) were more competitive than food lactobacilli (L. acidophilus and L. bulgaricus).
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Three azo compounds were synthesized in two different methods, and characterized by FT-IR, HNMR andVis) spectra, melting points were determined. The inhibitory effects of prepared compounds on the activity of human serum cholinesterase have been studied in vitro. Different concentrations of study the type of inhibition. The results form line weaver-Burk plot indicated that the inhibitor type was noncompetitive with a range (33.12-78.99%).
Zinc sulfide (ZnS) thin films were deposited on glass substrates using pulsed laser deposition technique. The laser used is the Q-switched Nd: YAG laser with 1064nm wavelength and 1Hz pulse repetition rate and varying laser energy 700mJ-1000mJ with 25 pulse. The substrate temperature was kept constant at 100°C. The structural, morphological and optical properties of ZnS thin films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscope (AFM) and UV-VIS spectrophotometer.
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Background: Leukemia is a broad term given to a group of malignant diseases characterized by diffuse replacement of bone marrow with proliferating leukocyte precursors. Chemotherapy has been increasingly used to treat malignant conditions. The systemic sequelae as a result of these immunosuppressive techniques induce many oral and dental complications. This study was conducted to evaluate the effect of chemotherapy on oral health status and activity of salivary alkaline phosphates enzyme in patients with acute lymphocytic leukemia. Materials and methods: The study groups included 28 patients with acute lymphocytic leukemia; they were under chemotherapy, aged 20-25 year old. The control group includes healthy subjects matching with study
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