The performance of asphalt concrete pavement has affected by many factors, the temperature is the most important environmental one which has a large effect on the structural behavior of flexible pavement materials. The main cause of premature failure of pavement is the rutting, Due to the viscoelastic nature of the asphalt cement, rutting is more pronounced in hot climate areas because the viscosity of the asphalt binder which is
inversely related to rutting is significantly reduced with the increase in temperature resulting in a more rut susceptible paving mixtures. The objective of this study is to determine the effect of temperatures variations on the permanent deformation parameters (permanent strain (p), intercept (a), slope (b), Alpha and Mu) as well as resilient strain (r) and resilient modulus (Mr). To achieve this objective, one aggregate gradation with 12.5mm nominal maximum size, two grades of asphalt cements (40-50 and 60-70) brought form Al- Daurah refinery, limestone dust filler has been used to prepare the asphalt concrete mixtures. 30 Marshall specimens were prepared to determine the optimum asphalt cement content. Thereafter, 30 cylindrical asphalt concrete specimens (102mm in diameter and 203 mm in height) are prepared in optimum asphalt cement and optimum ±0.5 percent. The prepared specimens were used in uniaxial repeated load test to evaluate the permanent deformation parameters of asphalt concrete mixes under the following testing temperature (5, 15, 25, 40 and 60c). The test result analyses appeared that Mr is decrease 51 percent when temperature increased from 5 c to 25 c and then decrease 22 percent with further increase in temperature from 25 c to 60 c. Also, the Alpha value decreases by a factor of 1.25 and 1.13 when temperature increases from 5 c to 25 c and 25 c to 60 c, espectively.
Finally, statistical models were developed to predict the Alpha and Mu parameters of permanent deformation.
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Coumarin derivatives have shown different biological activities, such as antifungal, antibacterial antiinflammatory, and antioxidant activities, besides antibiotic resistance modulating effects, and anti-HIV, hepatoprotective, and antitumor effect. So, new coumarin derivatives (hydrazones and an amide) were synthesized through multisteps reactions. All the synthesized target compounds were characterized by FT-IR spectroscopy, 1HNMR analysis. The compounds then evaluated for their anti-bacterial activity by means of well-diffusion method against two gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae) and two gram-negative bacteria (E.coli and Pseudomonas aeruginosa). The highest activity was demonstr
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Emily Bronte is born in Yorkshire on 30 July 1818. Her father, Rev. Patrick Bronte, is a man of intelligence and determination which enables him to gain an admission as a sizar to 81. John's Cambridge in 1802. He has six children where Emily is the fifth. The mother is a young beautiful girl who belong to an important family. Both Emily's parents try to teach
Their children well, support them all the time and elevate them to
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high levels. This causes an eagerness towards reading and writing, but the happiness of the children is affected by the sickness and later on by the death of their mother in 1821. After that things would
... Show MoreObjective: A descriptive design, using the methodological approach, is carried throughout the present
study from April 1st 2012 to May 20th 2013 to construct the school physical environment standardized
features tool.
Methodology: An instrument of (141) item is constructed for the purpose of the study. A purposive
sample of (44) school; (22) public and (22) private ones is selected. Content Validity of the instrument is
determined through the use of panel of (11) expert who are specialists in Community Health Nursing and
Community Medicine. Internal consistency reliability, using the split-half technique, is employed through
the computation of Cronbach alpha correlation coefficient of (0.93) for internal scale. Data
The current research is concerned with the study of (aesthetic discourse in the significance of commercial advertisement designs), according to a knowledge structure defined by function and creativity, and the main goal is to interpret the reality of forms, their various sources, their essence, meanings, formal relationships, and design ideas in order to achieve the visual goal as a typographic achievement. It arises through the designer’s internal mental intuition to produce shapes based on subjective feelings that refer his preconceptions about those shapes with his feelings to creative formations. Aesthetic discourse is produced from the mind depending on the various symbolic, psychological and social functions, production methods,
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Objective: The aim of the study is to assess the personal hygiene of adult patients with
diabetic foot.
Methodology: ٨ descriptive study was carried out in Baghdad teaching hospital, Al-Karama teaching hospital
and Al-Kindey teaching hospital for the period of 10/1/2006 to 1/9/2006. A purposive "non probability" sample
of (100) patient.
Questionnaire was constructed for achieving the purpose of the study. Data were collected through the
application of the questionnaire and interview technique. Data were analyzed through descriptive statistical
approach (frequency & percentage) and inferential statistical approach (chi-square ع correlation) by using of
SPSS.
Results: The study results indicated that the ra
The present study was conducted to evaluate the effect of variation of influent raw water turbidity, bed composition, and filtration rate on the performance of mono (sand) and dual media (sand and anthracite) rapid gravity filters in response to the effluent filtered water turbidity and headloss development. In order to evaluate each filter pe1formance, sieve analysis was made to characterize both media and to determine the effective size and uniformity coefficient. Effluent filtered water turbidity and the headloss development was recorded with time during each experiment.