Both traditional and novel techniques were employed in this work for magnetic shielding evaluation to shed new light on the magnetic and aromaticity properties of benzene and 12 [n]paracyclophanes with n = 3–14. Density functional theory (DFT) with the B3LYP functional and all-electron Jorge-ATZP and x2c-TZVPPall-s basis sets was utilized for geometry optimization and magnetic shielding calculations, respectively. Additionally, the 6-311+G(d,p) basis set was incorporated for the purpose of comparing the magnetic shielding results. In addition to traditional evaluations such as NICS/NICSzz-Scan, and 2D-3D σiso(r)/σzz(r) maps, two new techniques were implemented: bendable grids (BGs) and cylindrical grids (CGs) of ghost atoms (Bqs). BGs allow for the recording of magnetic shielding from the bent ring levels of [n]pCPs, while CGs provide tubular magnetic shielding scan (TMSS) maps detailing the magnetic shielding from a cylindrical region above and below the ring frame. Our findings suggest that smaller [n]pCPs with n < 6 exhibit deviations in the magnetic shielding above and below the ring, indicating a broken electron delocalization under the ring. In contrast, larger [n]pCPs tend to behave similarly to benzene in terms of magnetic shielding. Moreover, we found that shorter polymethylene chains of [n]pCPs exhibit significantly higher magnetic shielding interactions with the ring. Both of the above techniques offer new and promising tools for characterizing nonplanar aromatic compounds, thereby contributing to a deeper understanding of their magnetic and electronic properties.
Anew Schiff base (NaHL) has been prepared from the reaction between the salt of amino acid glycine with 2-hydroxy naphthaldehyde. By tridentate Schiff base of (ONO), donors were characterized by using U.V and spectrophotometer techniques. Complexes of Co(II) Ni(II) Cu(II) and Zn(II) ion with the ligand have been prepared, these complexes were identified by infrared, electronic spectral data, elemental analysis, magnetic moments, and molar conductivity measurements. It is concluded from the elemental analysis that all the complexes have (1:2) [metal:ligand] molar ratios, octahedral, with the exception to Zn(II) complex which have (1:1)[metal:ligand] molar ratio.
... Show MoreNew metal complexes of some transition metal ions Co(II), Cu(II) , Cd(II) and Zn(II) were prepared by their reaction with previously prepared ligands HLI= (P-methyl anilino) phenyl acetonitrile and HLII = (P-methyl anilino) –P– chloro phenyl acetonitrile . The two ligands were prepared by Strecker’s procedure which includ the reaction of p- toluidine with benzaldehyde and P- chlorobenzaldehyde respectively. Structures were proposed depending on atomic absorption , i.r. and u.v.visible spectra in addition to magnetic susceptibility and electrical conductivity measurements.
The article presents the synthesis and liquid crystalline properties of some of new bent and linear core compounds containing a 1,3,4-oxadiazole, piperazine and thiazolidin-4-one rings as a central core. The new synthesized compounds were characterized by elemental analysis and FTIR, ¹HNMR and mass spectroscopy). The liquid crystalline properties were studied by polarized optical microscopy and differential scanning calorimetry. All Schiff bases compounds with 1,3,4-oxadiazole and piprzaine ring in central core presented liquid crystalline properties. The liquid crystallinity of compounds containing 1,3,4-oxadiazole and thiazolidin-4-one rings as a central core were found depending on the type of terminal substituents.
This research includes the synthesis of some new nucleoside analogues via 1,3-
dipolar cycloadditon reaction starting with 1,3,4,6- Tetra- O-benzoyl –2 – azido-2-
deoxy- β – D- fructofuranose (F3) which was prepared in three steps ,protection
(benzoylation ) , bromination and azotation ((F1-F3) from D- fructose as sugar
moiety while the base moiety , 2-substituted benzimidaole derivatives (A1-A5)
were synthesized by condensation of O-phenylenediamine with different aromatic
aldehyde .
Nucleophilic substitution of propargyl bromide with benzimidaole derivatives (gave
the N- substituted compounds (B1-B5) which were reacted with azido sugar through
1,3- dipolar cycloadditon reaction to give nucleoside analo
The new ligand [3,3’-(1,2-phenylenebis(azanediyl))bis(5,5-dimethylcyclohex-2-en-1-one)] (L) derived from 5,5-Dimethylcyclohexane-1,3-dione with 1,2-phenylenediamine was used to prepare a new chain of metal complexes of Mn(ii), Co(ii), Ni(ii), Cu(ii), Cd(ii) and Zn(ii) by inclusive formula [M(L)]Cl2. Characterized compounds on the basis of 1H, 13CNMR (for ligand (L)), FT-IR and U.V spectrum, melting point, molar conduct, %C, %H and %N, the percentage of the metal in complexes %M, Magnetic susceptibility, thermal studies (TGA), while its corrosion inhibition for (plain steel) in tap water is studied by weight loss. These measurements proved th
The current study introduces a novel technique to handle electrochemical localized corrosion in certain limited regions rather than applying comprehensive cathodic protection (CP) treatment. An impressed current cathodic protection cell (ICCPC) was fabricated and firmly installed on the middle of a steel structure surface to deter localized corrosion in fixed or mobile steel structures. The designed ICCPC comprises three essential parts: an anode, a cathode, and an artificial electrolyte. The latter was developed to mimic the function of the natural electrolyte in CP. A proportional-integrated-derivative (PID) controller was designed to stabilize this potential below the ICCPC at a cathodic potential of −850 mV, which is crucial for prote
... Show MoreThe hydrodynamics behavior of gas - solid fluidized beds is complex and it should be analyzed and understood due to its importance in the design and operating of the units. The effect of column inside diameter and static bed height on the minimum fluidization velocity, minimum bubbling velocity, fluidization index, minimum slugging velocity and slug index have been studied experimentally and theoretically for three cylindrical columns of 0.0762, 0.15 and 0.18 m inside diameters and 0.05, 0.07 and 0.09 m static bed heights .The experimental results showed that the minimum fluidization and bubbling velocities had a direct relation with column diameter and static bed height .The minimum slugging velocity had an
... Show MoreThe thin films of cadmium oxide (CdO) were deposited using the SILAR (Successive ionic layer absorption and reaction) method at various deposition cycles. CdO thin films were made on glass substrates at a temperature of 95°C, using a cadmium acetate source material and an ammonium hydroxide solution. One of the main criteria that impact the quality of thin films is the number of deposition cycles. The size of the crystals decreases with the increase in the number of cycles from 33.7 nm at the immersion cycle 10 to 22.7 nm at the immersion cycle 20, as shown by the X-ray diffraction results. The optical band gap energy of the films reduces as the number of deposition cycles increases, while the transmittance of the Cadmium oxide film i
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