Quantum dots of CdSe, CdS and ZnS QDs were prepared by chemical reaction and used to fabricate organic quantum dot hybrid junction device. QD-LEDs were fabricated using layers of ITO/TPD: PMMA/CdSe/Alq3, ITO/TPD: PMMA/CdS/Alq3 and ITO/TPD: PMMA/ZnS/Alq3 devices which prepared by phase segregation method. The hybrid white light emitting devices consists, of three-layers deposited successively on the ITO glass substrate; the first layer was of N, N’-bis (3-methylphenyl)-N, N’-bis (phenyl) benzidine (TPD) polymer mixed with polymethyl methacrylate (PMMA) polymers. The second layer was QDs while the third layer was tris (8-hydroxyquinoline) aluminium (Alq3). The results of the optical properties show that the prepared QDs were nanocrystalline with defects formation. The calculated of energy gaps from photoluminescence (PL) spectrometer were 2.38, 2.69 and 3.64 eV for CdSe, CdS and ZnS respectively. The generated white light has acceptable efficiency using confinement effect which makes the energy gap larger, so that the direction of the light sites are toward the center of white light color. The hybrid junction devices (EL devices) were characterized by room temperature PL and electroluminescence (EL). Current-voltage (I–V) characteristics indicate that the output current is good compared to the few voltages ( 8-10.3 V) used which gives acceptable results to get a generation of white light. The EL spectrum reveals a broad emission band covering the range from 350 - 700 nm. The emissions causing this white luminescence were identified depending on the chromaticity coordinates (CIE 1931). The correlated color temperature (CCT) was found to be about 6250, 5310 and 5227K respectively. Fabrication of EL-devices from semiconductors material (CdSe, CdS and ZnS QDs) with hole injection organic polymer (TPD) and electron injection from organic molecules (Alq3) was effective in white light generation
Natural convection in a trapezoidal enclosure with partial heating from below and symmetrical cooling from the sides has been investigated numerically. The heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1/5, 2/5, 3/5, 4/5 are considered. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations discretized by finite volume method; body fitted coordinates are used to represent the trapezoidal enclosure, and grid generatio
... Show More134 samples of plants and animals wastes were taken from three different regions outside Baghdad and three different regions in Baghdad. 24 cellulolytic isolates fungi AO, C1, TH1, AN1, R1, TV, PG, AF, B1, L1, AP, TH, AP1, AN3, AO2, A, A1, C, F, AO1, C2, F1, CL and AP2 independent were chosen out of 48 selected fungi. The best optimal conditions for growth were 30ºC and pH 7. The isolates were identified and screened according to the colony diameter, biomass and density of spores in addition of capability to produce the hydrolytic enzymes for cellulose.
Background: Birth defects are the leading cause of both neonatal and post-neonatal deaths, as an estimated 240,000 neonates die in their first month of life worldwide each year. In Iraq, local studies have shown varying frequencies and types of congenital anomalies. Objectives: To provide new insight into the incidence and types of congenital anomalies and to explore their possible risk factors in Baghdad City. Methods: In this cross-sectional observational study, a total of 2007 neonates were enrolled from six hospitals in Baghdad during the period extending between September and December 2020. Hospital records and personal interviews were used for data collection. These data included the neonates' demographic and clinical characte
... Show MoreAdsorption experiments were carried out using two different low-cost sorbent materials, date seeds and olive seeds. These sorbents used as a single phase (not as mixture) to remove cadmium ions from simulated wastewater by adsorption process. The equilibrium time was found at 2 hr. The experiments include different parameters such sorbent type and weight and contact time. It was found that both of olive seed and date seed have approximately the same adsorption capacity (qm) with 15.644 mg/g and 15.2112 mg/g, respectively. Equilibrium isotherms and kinetic studies have been carried out. Langmuir isotherm model better fits the experimental data compared with the Freundlich isotherm for olive seed, while Freundlich isotherm fits for date se
... Show MoreAmong a collection of ground beetles from Iraq the new species Acinopus euphraticus was designated and described here. The erection of this new species was mainly built on external features and the description of male genitalia.
In this study, two correlations are developed to calculate absolute rocks permeability from core samples tested by Gas Permeameter Apparatus. The first correlation can be applied if K g≤100, the second correlation can be applied if Kg>100. Sixty core samples having different permeabilities to give a wide range of values that necessary to achieve a correlation.
The developed correlation is easily applied and a quick method to avoid repeating the test at different pressure values. Only one pressure test is required to reach absolu
... Show MoreAbstract The present work included morphological, anatomical, and palynological characters for the new species Acaalypha australis L. specimens, which belong to the family Euphorbiaceae. The species recorded in the study for the first time in Iraq. The plants of this species are annual herbs with green, striated or sub – polygonal stem, and branched near bases, Leaves are simple spirally alternate and lanceolate in shape. Flowers are unisexual, arranged in the axial of distinct leafy and cordate bracts, female flower arranged at the bracts bases and each flower with trileafed perianth and superior ovary with trilobed stylar stigma which has dense and coiled stigmatic hairs. Male flowers are arranged as a mixed verticellate inflorescence a
... Show MoreThe ground state proton, neutron and matter densities and
corresponding root mean square radii of unstable proton-rich 17Ne
and 27P exotic nuclei are studied via the framework of the twofrequency
shell model. The single particle harmonic oscillator wave
functions are used in this model with two different oscillator size
parameters core b and halo , b the former for the core (inner) orbits
whereas the latter for the halo (outer) orbits. Shell model calculations
for core nucleons and for outer (halo) nucleons in exotic nuclei are
performed individually via the computer code OXBASH. Halo
structure of 17Ne and 27P nuclei is confirmed. It is found that the
structure of 17Ne and 27P nuclei have 2
5 / 2 (1d ) an
