The Neutron Fermi Age, t, and the neutron slowing down density,   q (r, t) , have been measured for some materials such as Graphite and Iron by using gamma spectrometry system UCS-30 with NaI (Tl) detector. This technique was applied for Graphite and Iron materials by using Indium foils covered by Cadmium and the measurements done at the Indium resonance of 1.46 eV. These materials are exposed to a plane ²⁴¹Am/Be neutron source with recent activity 38 mCi. The measurements of the Fermi Age were found to be t = 297 ± 21 cm² for Graphite, t = 400 ± 28 cm² for Iron. Neutron slowing down density was also calculated depending on the recent experimental t value and distance.

This paper presents an experimental study for strengthening existing columns against axial compressive loads. The objective of this work is to study the behavior of concrete square columns strengthening with circulation technique. In Iraq, there are significantly more reinforced rectangular and square columns than reinforced circular columns in reinforced concrete buildings. Moreover, early research studies indicated that strengthening of rectangular or square columns using wraps of CFRP (Carbon Fiber Reinforced Polymer) provided rather little enhancement to their load-carrying capacity. In this paper, shape modification technique was performed to modify the shape (cross section) of the columns from square columns into circular colu

In this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d

The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θ_c) was changed. Geometrically, the acceptance half angle for standard CPC is (26^o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20^o, 26^o and 5

This paper compare  the accurecy of HF propagation  prediction programs for  HF circuits links between Iraq and  different points world wide  during August 2018 when  solar cycle 24 (start 2009 end 2020) is at minimun activity and also find out the best communication mode  used. The prediction   programs like Voice of America Coverage Analysis Program (VOACAP) and ITU Recommendation RS 533 (REC533 )  had been used to generat HF circuit link  parameters like Maximum Usable Frequency ( MUF) and Frequency of Transsmision (FOT) .Depending  on the predicted parameters (data)  , real radio contacts had been done using a radio transceiver from Icom  model IC 7100 with 100W RF

The synthesis of the bisaldehyde ligand 2-(1,1-dimethyl-1,3-dihydro-2H-benzo[e]indol-2-ylidene)malonaldehyde (B) and its coordinated compounds with Cr(III), Mn(II), Fe(II), Co(II), Ni(II) and Cu(II) ions are reported. The synthetic route of B was completed by adopting the Vilsmeier-Haack reaction. This was based on the mixing of 1,1,2-trimethyl-1H-benzo[e]indole with phosphoryl trichloride and N, N-dimethylformamide (anhydrous) that gave the aminomethylenemalondialdehyde. The use of POCl3 and DMF was aimed to give the Vilsmeier-Haack intermediate, which was kept at 5°C and then heated with stirring at 85°C. The addition of an aqueous NaOH solution (35%) to the reaction mixture resulted in the isolation of B. The monomeric coordinated comp

This study reports the formation, characterisation and biological evaluation of a Schiff base ligand and its corresponding metal complexes. The Schiff base ligand (HL) was prepared through a condensation reaction involving isonicotinohydrazide and N'-((1R,2R,4R,5S, E)-2,4-bis(4-chlorophenyl)-3-azabi cyclo[3.3.1]nonan-9-ylidene) isonicotinohydrazide (M) in EtOH solvent and (3-5) drops of conc. HCl. The interaction of HL with selected metal chlorides including Mn(+2), Co(+2), Ni(+2), Cu(+2) and Zn(+2) in a 2:1 (L:M) mole ratio resulted in the synthesis of complexes with the general formula [M(HL)Cl2] (where: M = Mn(+2),Co(+2) and Ni(+2)) and [M`(HL)Cl2] (where M` =  Cu(+2) and Zn(+2)). The characterisation of the prepared compounds w

The formation and structural investigation of three new Mannich bases are reported. The synthesis of these compounds was accomplished via a multicomponent one-pot reaction using CaCl2 as a catalyst. The reaction of the benzaldehyde, m-bromoaniline and cyclohexanone or 4-methylcyclohexanone resulted in the formation of L1 and L3, respectively. The synthesis of L2 was achieved by mixing benzaldehyde, o-bromoaniline and cyclohexanone. The isolated compounds were characterised using a range of analytical and spectroscopic techniques. These include; NMR (1H and 13C-NMR), ESMS, FTIR, electronic spectroscopy, microanalyses and melting points. The NMR data for L1 and L2 indicated the presence of one isomer in solutions, on the NMR time scale. How