Laboratory studies were conducted at the biological control unit, college of Agriculture, University of Baghdad to evaluate some biological aspects of the predator Chilocorus bipustulatus (Coleoptera: Coccinellidae), which is considered one of the most important predators on many insect pests, especially the scale insect, Parlatoria blanchardi, (Homoptera: Diaspididae) on date palms. The results showed that biological parameters of the predator were varied according to different degree of temperature. Egg incubation period was significantly different and reached to 7.5 and 5.44 day at 25 and 30°C respectively, Fertility was the same 100% at both temperature degrees. Larval growth periods were 17.41 and 16.12 day as well as the mortality during this stage was also the same 0.0%. Duration rate of pupal stage was 9.62 day at 25°C and reduced significantly to 7.13 day at 30°C. No morality was found, in pupal stage at both temperatures. The adult longevity rates for both males and females were also significantly different that the adult longevity of the male was 80.87 and 66.75 day and less than that of female longevity rate which reached to 90.89 and 67.0 days at both temperature degrees of 25 and 30°C, respectively. Fecundity affected significantly and reached to 254.3 and 316.0 egg female at 25°C and 30°C, respectively. The predator has very high consumption efficiency of scale insect nymphs, this predation was increased as the larva developed from one instar to the following. As average the 1ˢͭ, 2ⁿᵈ, 3ͬ ͩ and 4ᵗͪ instars were consumed 95.12, 171.4, 328.06 and 710.0 scale insect nymphs, and the average of daily consumption of each instar reached to 23.78, 34.28, 65.61 and 140.2 nymph, respectively. The average rate for the whole larval stage consumption was 263.87 and 1295.58. The female of predator consumed more nymphs (127.5 nymph/ day) than that of male (106 nymphs/ day).
In this paper, a polymer-based composite material was prepared by hand Lay-up method consisting of epoxy resin as a base material reinforced by magnesium oxide powder once and silicon dioxide powder again and with different weight ratios (3, 6, 9 and 12) wt %. The three-point bending test was performed in normal conditions and after immersion in sulfuric acid. The results showed that the bending value decreased with the increase of the weighted ratio of the reinforcement material (MgO, SiO2). The Bending of samples reinforced by SiO2 was found to be less than the bending of samples reinforced by particles (MgO). For example, the bending of the SiO2 sample (0.32 mm) at the weighted ratio (3%) and for the MgO (0.18mm) sample at the weight
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The stories of children in Iraq during the past two decades have received a number of important scientific studies. Despite tyranny of the historical study method on most of these studies, they have been and still are very important, because they have established a chronicle of this literary style that has been neglected and based not only on the academic level and serious in-depth university studies but also on the enclosed sight that doesn’t consider studied art as an innovation with its specificity and its typical technical components. While many of the public impressions and self-reflections contributed to the dominance of some of the provisions and concepts that were circulated as critical remarks and adopted by som
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In earthquake engineering problems, uncertainty exists not only in the seismic excitations but also in the structure's parameters. This study investigates the influence of structural geometry, elastic modulus, mass density, and section dimension uncertainty on the stochastic earthquake response of a multi-story moment resisting frame subjected to random ground motion. The North-south component of the Ali Gharbi earthquake in 2012, Iraq, is selected as ground excitation. Using the power spectral density function (PSD), the two-dimensional finite element model of the moment resisting frame's base motion is modified to account for random ground motion. The probabilistic study of the moment resisting frame structure using stochastic fin
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This paper studies the behavior of reinforced Reactive Powder Concrete (RPC) two-way slabs under static and repeated load. The experimental program included testing six simply supported RPC two-way slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. All the tested specimens were identical in their material properties, and reinforcement details except their steel fibers content. They were cast in three pairs, each one had a different steel fibers ratio (0.5 %, 1 %, and 1.5 %) respectively. In each pair, one specimen was tested under static load and the other under five cycles of repeated load (loading-unloading). Static test results revealed that increasing steel fibres volume fraction from 0.5 % to 1 % and from 1% to 1.5%,
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In this study, the effect of glass fiber reinforced polymer (GFRP) section and compressive strength of concrete in composite beams under static and low velocity impact loads was examined. Modeling was performed and the obtained results were compared with the test results and their compatibility was evaluated. Experimental tests of four composite beams were carried out, where two of them are control specimen with 20 MPa compressive strength of concrete deck slab and 50 MPa for other. Bending characteristics were affected by the strength of concrete under impact loading case, as it increased maximum impact force and damping time at a ratio of 59% and reduced the damping ratio by 47% compared to the reference hybrid beam. Under stat
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The Arab Islamic Manuscripts in the science libraries humanly global heritage in different types of knowledge and science, as they were not confined to a particular flag but extended to include all kinds of science, and to facilitate the knowledge of these types of manuscripts has been necessary to operate them indexed in most libraries , because it is important in determining the size of those manuscripts and set them up and facilitate the work of the investigators, as well as the significance of indexing to know printed manuscripts in order to avoid repetition of the publication of the manuscript more than once, especially if the deployment is to be characterized by accurate scientific integrity and following the origins of the scienti
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