Reproduction potential and age –specific fecundity of the Mealybug Planococcus citri Risso were studied in the laboratories of Biological control research unit,college of Agriculture –Baghdad university at 25± 2Cº and 60-70% R.H.with 16 light:8 dark photo period.The results showed that the survival ratio began to decline at the 38th day, the average female age was 20 days ,while the average age was 8 days at the first reproduction . Net reproduction rate ( Ro ) was 58.59 female female generation which prove that the population of the mealybug was of the unstable kind , intrinsic rate of increase (rm) was 0.118 femalefemale and the average length period of generation ( T ) was 34.30 days . Many local predators attack the mealybug such as two species of chrysopid ,Chrysoperla carnea and C.mutata and the Dipterian predator Dicrodiplosis manhoti. Also more than 10 coccinellid predators, such as, Nephus jaderiensis , Scymnus syriacus , coccinella septempunctata and C.undecimipunctata .This predators play important role as a bio-control agents to decline the population densities of mealybug naturally in IRAQ .
This paper studies the influence of temperature on the corrosion rate of coated AA6111 aluminum alloy used in vehicle bodies under static and vibration states. The vibration test system was collected laboratory and used for testing of five different types of paints (EASI, Numix, Lesonal, DENSO and Polaron paints) in the 5 % NaCl solution using immersion test method. Lesonal paint provided the best corrosion protection, while DENSO paints show large values of corrosion rate, other coatings exhibit moderate values. Model of paints corrosion was developed to characterize the corrosion processes occur at the surfaces. It is found that corrosion rate obtained at vibration cases is larger than static cases and vibration effect
... Show MoreThe paper presents an investigation to the flutter speed of composite wing for different ply orientation. Structurally the composite wing was idealized as a composite beam load carrying structure. Theodorsen’s expression was used to get the 2- dimension unsteady lifting force and pitching moment in the limit of incompressible flow and subsonic speed which were integrated over the wing span. A free vibration analysis was first carried out to get the natural frequencies and mode shapes .The velocity-damping (V-g) method was used to calculate the flutter speed and the flutter frequency. A wing of unmanned aerial vehicle was manufactured from woven glass and polyester resin where the flutter speed was calculated experimentally by the wind
... Show More
In this work, we introduced the Jacobson radical (shortly Rad (Ș)) of the endomorphism semiring Ș = ( ), provided that is principal P.Q.- injective semimodule and some related concepts, we studied some properties and added conditions that we needed. The most prominent result is obtained in section three
-If is a principal self-generator semimodule, then (ȘȘ) = W(Ș).
Subject Classification: 16y60
generator the metal conductor is replaced by conducting gas plasma.
Information and Communication Technology revolution has led to the emergence of electronic payment systems and their means And that the replacement of these modern means replace the traditional means (legal money) issued by the Central Bank has influenced the performance of monetary policy, especially that monetary policy is one of the most important policies used to achieve economic stability , The aim of the research is To know the impact of electronic payment systems on the tools of monetary policy as these means, such as cards and electronic money issued by credit institutions and companies, that is, the Central Bank is not responsible for issuance and spread And the lack of regulation by the Central Bank will lea
... Show MoreThe present studies are focused on the modification of the properties of epoxy resin with different additives namely aluminum, copper by preparing of composites systems with percentage (20%, 40% and 50%) of the above additives. The experimental results show that the D.C of conductivity on wt% filler content at ( 293-413 ) K electrical conductivity of all above composites increased with temperature for composites with filler contact and find the excellent electrical conductivity of copper and lie between (2.6*10-10 - 2.1*10-10)?.cm . The activation energy of the electrical conductivity is determined and found to decrease with increasing the filler concentration.
This work aimed to use effective, low-cost, available, and natural adsorbents like eggshells for removal of hazardous organic dye result from widely number of industries and study the influence of different eggshell particle size (75, 150) Mm. The adsorbent was characterized by SEM, EDX, BET and FTIR . The initial pH of dye solutions varying from 4 to 10 , the initial concentrations of methyl violet (MV) 2B range (20-80) mg/L, dosage range (0.5-10) g, contact time (30-180) min, and particles size of the adsorbent (75, 150) Mm were selected to be studied. Two adsorption isotherms models have been used to fit the experimental data. Langmuir and Freunlich models were found to more represent the experiments with high
... Show MoreZnS thin films were grown onto glass substrates by flash evaporation technique, the effects of ? – rays on the optical constants of ZnS these films were studied. It was found that ? – rays affected all the parameters under investigation.
Conventional flexible pavements are released to different types of failure in the initial phases of their service life due to high traffic density, high speeds, heavy loads, and harsh climates. To eliminate pavement damage and failure early, the present search investigates the impact of adding glass, steel, and basalt fibers in the asphalt mixtures. Also, the study evaluates these materials characteristics compared to the mixtures without fibers. The Marshall test and tensile strength ratio test (TSR) were utilized to evaluate the asphalt mixture's performance. A set of specimens were produced by incorporating glass fiber (GF), steel fiber (SF), and basalt fiber (BF) at (0.10%, 0.15%, 0.20%), (0.25%, 0.35%, 0.45%), and (0.15%, 0.35%
... Show MoreImproving the permanent deformation resistance of asphalt pavements is a vital challenge. Nanomaterials have emerged as promising additives due to their ability to enhance the binder stiffness and elasticity. This study evaluated the influence of five nanomaterials, namely Nano-Silica (NS), Nano-Alumina (NA), Nano-Zinc (NZ), Nano-Titanium (NT), and Carbon Nanotubes (CNTs) incorporated into a base asphalt binder at varying dosages, with up to 10% for NS, NA, and NT, and up to 5% for NZ and CNT. Fifteen modified binders were assessed using the Multiple Stress Creep Recovery (MSCR) test to obtain non-recoverable creep compliance (Jnr), while the corresponding hot mix asphalt samples underwent repeated load testing and rut depth predict
... Show More