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[en] This paper discusses the current legal issues related to relationship between chemistry and construction, performs about some important branches of chemistry in construction, such as chemical physics, chemistry of bending materials and chemical processes, which occur during producing of construction materials. A short analysis of these branches of chemistry can surely make conclusion about further participation of chemistry in construction. Also by practical-experimental way was proved the main role of chemistry in construction. (author)

[en] Tetrahydroquinolines bearing substituents are frequently found as a substructure in a number of alkaloids and natural products. Since their individual stereoisomers displays different biological activities, it is desirable to develop a highly stereoselective synthetic method for tetrahydroquinolines. While some progress has recently been made toward the development of asymmetric synthetic methods for tetrahydroquinolines, it is still a challenging topic in organic synthesis. In order to investigate the source of diastereoselection attained in the substitution reaction with a racemic epoxide, we examined the substitution of 2 with an excess amount of racemic p-chlorophenyl-substituted oxirane. We have developed a novel method for the asymmetric synthesis of trans-3,4-diaryl-substituted tetrahy- droquinolines from ortho-substituted N-pivaloyl anilines. The enantioselective process includes (+)-sparteine-mediated stereoselective lithiati on, kinetic resolution of epoxides in substitution, and stereospecific Mitsu nobu cyclization as the key reactions. The simple protocol can provide highly functionalized tetrahydroqu inoline rings and would allow their further functionalization to access more complex target molecules

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[en] Ti MCM 41 were synthesized and evaluated in the epoxidation of limonene, using peroxide of hydrogen (H₂O) as agent oxidizer. The characteristic hexagonal phase of Ti MCM 41 was obtained by heating the precursor gel during three days at 100 centigrade degrees. Further heating up to ten days leads to a decrease of this phase. The increase (Ti) in the synthesis gel also decreases that phase. The increase of Ti in the synthesis gel also decreases that phase UV VIS and FTIR spectroscopy indicates that Ti was incorporated in the lattice of Ti MCM 41 as well as, in Ti BETA. SEM micrographs of Ti MCM 41 show that the morphology changes with the Ti loading. Ti MCM 41 was most active than Ti BETA for limonene epoxidation even though both show high selectivity to epoxides

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[en] The effect of a side notch used as a crack guide in a double-cantilever-beam specimen is investigated. The resulting stress distribution along the section of symmetry ahead of the notch is obtained from a three-dimensional photoelastic model. The effect of this side notch, through the thickness and down the side of the specimen is determined. After stress freezing, the model was sliced along principal planes. Along the x-x plane of symmetry, the principal stresses were determined by graphical integration of Filon's transformation of the Lame'-Maxwell equations and by subslicing along the x-z plane. Results of the investigation are in good agreement with those of other investigators. The side notch increases the value of the maximum tensile stress at the intersection of the starter notch and the side notch by approximately 22 percent. (auth)

[en] Leptadenia pyrotechnica (Forssk.) Decne is a medicinal plant that is native to hot deserts of Pakistan. This plant is sporadically known with reference to bioactivity including phytochemical screening especially from Pakistan. The present study was designed to screen out four major groups of phytochemicals such as alkaloids, flavonoids, saponins and tannins from eight solvents based roots and aerial parts extracts viz., hexane, chloroform, acetone, ethyl acetate, butanol, ethanol, methanol and water of the selected plant. The qualitative screening showed the presence of all major groups of phytochemicals in both plant parts extracts in which methanolic ones were the most efficient that extracted all the selected classes of phytochemicals. Quantitative screening revealed various concentrations of selected phytochemicals in both plant parts. The alkaloid contents were 3.267±0.643and 3±0.6 in roots and aerial parts respectively (p>0.05). The total flavonoid content was 76.867±2.266 and 139.448±8.677 QE/100g in roots and aerial parts respectively. In the case of total saponin contents, the proportions were 0.34±0.013% and 0.4 0.010% in roots and aerial parts respectively, whereas; total tannin contents were 62.713±4.841 and154.961±5.853 mg of TAE/100g of extract in roots and aerial parts, respectively. This study will serve as a benchmark for further pharmacological studies on the said plant that may be harnessed for drug development in the future. (author)