The Bi2Se3 compound was synthesis by fusing initial compounds consisting of
extra pure elements in stoichiometric ratio from elements compound, charged inside
quartz ampoule. The crystal growth of Bi2Se3 carried out using Brighaman technique
process from melting f (Bi+Se ) at temperature of 810 ºC for about 48 hrs. Single crystal
of Bi2Se3 has been grown in direction (211) after slow cooling on account of heat
gradient to zone furnaces at cooling rate (1-3) C/hr. The structure study of the compound
was determined by x-ray diffraction technique, which it has bismuthinite structure and
orthorhombic unit cell with lattice parameters of a=10.2678 Å, b=11.2392 Å and
c=5.1737 Å

Background:  There is a strong desire of adolescent to have a peer group and to be appreciated and also to become a member of this group which can affect one each other. There for; encourage, adapting,and imitating of friends and group consider as the main reasons behind starting of smoking among youngsters. Smoking habits in the family were found tobe acause of smoking pressure among adolescentas peer pressure. Smoking habit may be started before 18 years of age in most adult smokers.

Objectives: To study the effect of peer pressure and family smoking habiton the prevalence of smoking among secondary school students.

Type of the study:  A cross

   In this study, the contribution of the bond C–I has been derived and incorporated in empirical formula to calculate zero-point energies (ZPE) of Iodo compounds. The calculated ZPE for 38 molecules containing this bond correlate well with experimental values. The comparison of these results with semiempirical (AM1) ZPE appears very satisfactory

The 4-(?-bromo acetyl)-4?-toluene sulfonanilide (2) was used as key intermediate to synthesize new heterocyclic compounds. This bromo compound was synthesized via sulfonation of amino group of p-amino acetophenone using Hinsburg method with 4-toluene sulfonyl chloride to form 4-acetyl-4?-toluene sulfonanilide (1) which is used as a starting material in this work. This compound was brominated to yield compound (2) which is used as a precursor to synthesize new five and seven membered heterocyclic compounds such as substituted 1,3-oxazoles (3,4), 1,3-thiazole derivatives (5-7), thiourea compounds (8a,b), 1,3-Thiazoline-2-thione compounds (9a-f) and 1,2,5-triazepine compounds (11a-d). The synthesized compounds were identified depending u

The work involves synthesis of new Schiff bases ([V] a, b and [VI] a, b), pyrazoles [VII] a, b and pyrazolines [VIII] a, b derivatives containing isoxazoline unit starting with chalcones. 4-bromoacetophenone was reacted with 4-hydroxybenzaldehyde or 4-hydroxyacetophenone was reacted with 4-bromobenzaldehyde in basic medium to give chalcone by Claisen-Schemidt reaction. The chalcons [I] a, b was reacted with hydroxylamine hydrochloride to form isoxazolines [II] a, b. which were reacted with ethyl chloro acetate in basic medium to get ester compounds [III] a, b. The condensation new ester [III] a, b with hydrazine hydrate80% yieldedacid hydrazide [IV] a, b. The later compound refluxing with 4-substituted benzaldehyde in dry benzene to give Sc

The work involves synthesis of new Schiff bases ( [V]a, b and [VI]a, b), pyrazoles[VII]a, b and pyrazolines[VIII]a, b derivatives containing isoxazoline unit starting with chalcones. 4bromoacetophenone was reacted with 4-hydroxybenzaldehyde or 4-hydroxyacetophenone was reacted with 4-bromobenzaldehyde in basic medium to give chalcone by Claisen-Schemidt reaction. The chalcons [I]a, b was reacted with hydroxylamine hydrochloride to form  isoxazolines [II]a, b. which were reacted with ethyl chloro acetate in basic medium to get ester compounds[III]a, b .The condensation new ester[III]a, b with hydrazine hydrate80% yieldedacid hydrazide [IV]a, b.The later compound refluxing  with  4-substituted benzaldehyde in dry benzene to