The investigation of the effect of tempering on thermal analysis of
Al-Ti-Si alloy and its composites with MgO and SiC particles was
performed. Thermal analysis was performed before and after
tempering by DSC scan. Optical microscopy was used to identify the
phases and precipitations that may be formed in base alloy and
composites. X-ray diffraction test indicated that the Al3Ti is the main
phase in Al-Ti-Si alloy in addition to form Al5Ti7Si12 phase. Some
chemical reactions can be occurred between reinforcements and
matrix such as MgO.Al2O3 in Al-Ti/MgO, and Al4C3 and Al(OH)3 in
Al-Ti/SiC composite. X-ray florescence technique is used to
investigate the chemical composition of the fabricated specimens.
Heat treatment (Tempering) changes the microstructure of base alloy
and its composites which was assessed by DSC scan. Generally,
three main peaks appeared in DSC represented by GP zone, S phase
(precipitations) and dissolution of phases or precipitations. After
tempering, composite with SiC particles showed better results than
base alloy and composite with MgO. Since the optical microscopy
revealed reforming the stable phase Al3Ti with evaporation some
gases from composite. DSC analysis showed the stability of
composite with SiC was up to 270oC.
The filler in the asphalt mixture is essential since it plays a significant role in toughening and stiffening the asphalt. Changes in filler type can lead the asphalt mixtures to perform satisfactorily during their design life or degrade rapidly when traffic and environmental effects are considered. This study aims to assess the impact of filler types such as limestone dust (LS) and hydrated lime (HL) on Marshall characteristics and moisture damage in asphalt mixtures. Three different percentages of HL were employed in this study to partially replace the LS mineral filler: 1.5, 2.0, and 2.5% by aggregate weight. Furthermore, a control mixture was created with 7% LS by overall aggregate weight for the wearing course layer. The Marsha
... Show MoreTigris River is one of the main important surface water resources in Iraq. This necessitates continuous study of its quality . The present study is concerned with the characteristics and quality of Tigris water passing through in Baghdad city. (eight) samples were collected from the river in the area Grea't City. The study periods were carried over four season, which has been sampled once represent the every season. First sampling 12-11-2012 represent the autumn season The second sampling 20-1-2013 to represent the winter season. The third in 25-3- 2013 to represent the Springer season. The fourth during 29-5-2013 to represent the summer spring season. In order to specify the water quality, a group of physical and chemical analyses have bee
... Show MoreAbstract The present study on the prevalence of intestinal parasitic infection from July 2003 to July 2004 ,was conducted among children aged(less than 5 -14 )years attending AL-Daura Health Centre in Baghdad City .(350) specimen were choosen randomly and examined, 160(45.7%) of these were infected , 140 (87.5%) harboured one parasite while 20 (12.5%) harboured more than one parasite.190 (54.3%) were non infected with any of intestinal parasite . It was observed that the most common intestinal protozoa among children is Giardia lamblia, followed by Entamoeba histolytica and Blastocystis hominis with pre
The effects of temperature on an exotic aquatic snail Pomacea canaliculata (Lamarck, 1819) collected from the Shatt Al-Arab intertidal zone were investigated. A series of laboratory experiments were conducted during the summer period of 2017. Individuals of new born snails hatched in the laboratory from adult snails were collected from Shatt Al-Arab intertidal zone, and subjected to five fixed temperatures: 15, 25, 35, 40 and 45 Cº, after short term thermal acclimation. The heartbeats (HB) were counted at each temperature level. The results showed significant direct increase of HB from 15 Cº (19.8 HB/min) up to 25 Cº (76 HB/min) (P<0.05) as well as from 25 Cº to 35 Cº (93 HB/min). At 40 Cº the snail HB
... Show MoreA study carried out in quail’s field owned by the Department of Animal production/ Collage of Agriculture / Tikrit University. For the period 14/ 5/ 2016 to 4/ 6/ 2016 in order to study the effect of adding Curcuma longa - to the diet of quails - on some productive and physiological characteristics of the Japanese quail birds bred for meat production. Using (48) quail birds which are two weeks old provided by Department of Agricultural Research. The birds were divided randomly after weighing them into three treatments; four replicate treatments for (4 bird/ replicate). The treatments as follows: (T1) control group (fed diet without any supplement), second (T2) and third (T3) groups were fed diet supplemental 4.5 and 9g Curcuma powder /
... Show MoreThe result revealed that the peak of population density of cabbage aphid Brevicoryne brassicae was 523.20 individuals/plant on 21 March in edges of rapeseed field and was 1141.67 individuals/plant in center of the field. Results revealed that population density of cabbage aphid in rapeseed fields surrounded by cover crops significantly were low compared with that of monoculture rapeseed. The location of rapeseed plants (in edges or in center) significantly affected (p<0.05) the tested pest density, e.g. optimum density was 146.69 individuals/plant in the center of the field. Whereas was 93.32 in the edges. Effect of the interaction between location and surrounding vegetation was significant on aphid density, which their population densit
... Show Moreالخلاصة
تتناول هذه الورقة مخططات وسياسات الاستيطان في الضفة الغربية والقدس الشرقية منذ العام 1967، عبر سياسات قادها حزب العمل وأكملها حزب الليكود وكاديما وبقية الأحزاب الإسرائيلية، تلك السياسات التي استهدفت فرض السيطرة السياسية الكاملة على الأرض، وما نتج عن ذلك من سيطرة حصرية على الأرضوتقييد استخداماتها، ومحاصرة الوجود الفلسطيني والتضييق عليه، وتحويل مراكز ال
... Show More The current research aims to highlight the role of human resource management with its practices (human resource planning, selection and placement, training and development, performance evaluation, compensation, and incentives) in raising the level of individuals' performance and its dimensions (task performance, contextual performance, unproductive work behavior, and adaptive performance) by explaining the research problem, which can be limited to the low level of performance of individuals, where the researchers use the descriptive analytical approach and the SPSS program in the practical aspect of the research community represented by the general manager and his assistant