Исследование механических свойств материалов на основе графена C-=SUB=-62-=/SUB=-H-=SUB=-20-=/SUB=- и полиэтилена (-CH-=SUB=-2-=/SUB=--CH-=SUB=-2-=/SUB=--)-=SUB=-n-=/SUB=-

In the paper, the mechanical properties of the materials based on graphene С62Н20 and polyethylene (-СН2-СН2-)n have been investigated by using semiempirical PM3 method, and the visual models of molecules have been constructed (-СН2-СН2-)n. The calculated values of mechanical parameters show that these materials possess a high elasticity and strength. The orbital energies, potentials of ionization, full energies of electrons, strengths, etc. for given material have been calculated. Opportunity of using these light materials in engineering industry for making of superstrong protective thin coating on car bumpers have been considered. The necessary minimal thickness of protective coating during two cars collision with given mass and speed has been calculated that bumpers do not damage.

QSAR treatment of meisoindigo derivatives as a potentbreast anticancer agent

A quantitative structure-activity relationship (QSAR) analysis of meisoindigo derivatives as a breast anticancer has been carried out. This study aimed to obtain the best QSAR model in order to design new meisoindigo based compounds with best anticancer activity. The semiempirical PM3 method was used for descriptor calculation. The best QSAR model was built using multilinear regression (MLR) with enter method. It was found that there were 19 new meisoindigo derivativeswith better predictive a potent anticancer agent. The best compound was (E)-2-(1-((3-ethylisoxazol-5-yl)methyl)-2-oxoindolin-3-ylidene)-N-(4-methoxyphenyl)acetamide with the value of IC505.31144 x10-15 (μM).

ANALISIS QSAR SENYAWA TURUNAN MEISOINDIGO SEBAGAI ANTIKANKER PAYUDARA

Quantitative Structure and Relationship (QSAR) of meisoindigo derivative compounds was successfully carried out. The purpose of this study was to find out the best model of meisoindigo derivative compounds as breast anticancer. The research method of this research using the semiempirical PM3 method. The semiempirical method of PM3 was chosen as a better method because it has model results that more represent physicochemical aspects. The selection of the best mathematical model is done by multilinear regression statistical analysis of the calculation data obtained. The results of this study formulate model 5 as the best model with a formula Log 1/IC50 = 44.316 + (-0.0000282*Eis.at) + (-0.257*µ) + (-0.054*LogP) + (0.014*EH) + (-7.241*qC6) + (-1.734*qC9) + (25.711*qO10) + (7.309*qN11) + (94.825*qC13) + (58.794*qO14) + (5.866*qC15)

Моделирование электронной структуры композитного материала графен-поливинилиденфторид

Theoretical models of shockproof composite materials based on two-layer graphenes and multilayer polyvinylidene fluoride C_124H_40 + n (H–(C_2H_2F_2)_5–H) ( n = $$\overline {1,\;8} $$ ) are constructed. The electronic structure is studied using the semiempirical PM3 method that is one of version of the molecular orbital method. The orbital energies, ionization potentials, total electron energies, strength, and other properties of the considered material are calculated based on the theoretical models. The outlooks for application of these materials in the military field for manufacturing superstrong and lightweight flak jackets are considered.

Desain Senyawa Turunan Karbamat Sebagai Insektisida Baru Menggunakan Metoda In Silico

Linear equation of QSAR model of insecticidal activity of carbamate derivatives based on atomic charge and hydrofobic, electronic and steric descriptors has been investigated. The descriptors were calculated by semiempirical PM3 method and biological activities of the compound were taken from experiment. The relationship between descriptors and their biological activities was analyzed with multilinear regression analysis.The best linier equation resulted from that analysis is : Log 1/LD 50 = 12,651 + (2,467 qC2) + (2,832 qC4) - (14,089 qC6) - (0,24 qO7) + (0,293 μ) - (0,08 SA (grid)) +(0,041 V)+ (0,141 EH) - (0,303 log P) n = 39 ; r = 0,839 ; adjusted r2 = 0,612 ; SE = 0,355; Fhit/Ftable = 3,443 PRESS=5,188 Based on that model, a new carbamate derivative has been designed which show better predicted activity (log 1/LD50 = 9,79) while the old one (log 1/LD50 = 8,81). This new carbamate insecticide derivative can be synthesized laboratoriccally for the next prove. Key Word:QSAR, Insecticides carbamate, PM3.

Aromatic C-H Bond Rupture; a Density Functional, B3LYP, Study

Unrestricted Density Functional (B3LYP) calculations with the 6-311G(d) basis were done for benzene (C6H6) with successive elongation of one C-H bond. Gradual increase in the total energy resulted til C-H bond length of about 3.7 Å , followed by a sudden decrease in energy on further elongation of the bond. The estimated activation energy for the reaction was 152.346 kcal/mol, much higher than the value calculated with the semiempirical PM3 method.

Sterically Crowded Heterocycles. XI. A Semiempirical Prediction of Enantiomerization Barriers for Substituted (Z)-3-(Imidazo[1,2-a]pyridin-3-yl)-1-phenylprop-2-en-1-ones

Conformational behaviour and racemization paths of the parent skeleton are discussed using a threedimensional Φ,Ψ-energy map calculated by the semiempirical PM3 method. To restrain the number of possible racemization paths, a less sophisticated approach based on the PM3 heat of formation - torsion angle Φ relationships has been used for 5-substituted title molecules; the role of non-planar enantiomeric transition states is postulated. Plausibility of the simple theoretical procedure has been tested using two phenyl derivatives of the title compounds for which experimental barriers to racemization are accessible.