GC/MS analysis of the essential oils of Cupressus arizonica Greene, Juniperus communis L. and Mentha longifolia L.

ABSTRACT. The chemical composition of the essential oils obtained by hydrodistillation from Cupressus arizonica Greene, Juniperus communis L. and Mentha longifolia L. were determined by gas chromatography-mass spectrometry (GC/MS) analysis. The chemical composition of the essential oils were identified by GC/MS. Eicosane (27.4%), umbellulone (13%) and α-pinene (10.51%) were the major components of C. arizonica oil; sabinene (32%), limonene (26%) and bornyl acetate (7.4%) were the major components of J. communis oil and pulegone (26%), L-menthone (13.4%) and cis-para-menthan-3,8-diol (10.2%) were the major components of M. longifolia oil. The percentage of monoterpenes in the three essential oils was compared. The percentage of monoterpenes in C.arizonica is about 5.2%, J. communis 46%, and M. longifolia is 50.1%. The percentage of terpenes in C. Arizonica (16.3%), J. communis (5.2%) and M. longifolia (9.3%) were reported. But the percentage of cyclic monoterpenes in C. arizonica is about 6%, J. communis 26.1%, and M. longifolia is 3%. Monoterpenes are the most components that make up essential oils.               KEY WORDS: Cupressus arizonica, Juniperus communis, Mentha longifolia, Essential oil, Chemical composition Bull. Chem. Soc. Ethiop. 2019, 33(3), 389-400.DOI: https://dx.doi.org/10.4314/bcse.v33i3.

Experimental investigation the effect of T-shape spur dike's angel on rip rap stability to bank protection of navigation river in 90 degree bend

One of the most important topics in river engineering is protection of banks. Because of change in flow characteristics the banks of rivers will be remove that it is very sever. Use of spur dikes is one of the common methods for protection of banks but there is a problem in this field that is protection of spur dikes which there isn’t many research about it. Because the spur dikes are very useful in the bends therefore this research carried out in the 90 degree bends. In this research the goal is investigation of the of spur dikes angel on stability if riprap. For achievement of this goal use three length of nose of spur dike (50%, 75% and 100% of body length of spur dike) and three diameter of rip rap (1.51cm, 1.12cm, 0.72cm). The results showed that in all of the experiments increase in angel of nose cause decrees in Froude number of flow, densimetric froud number of sediment in failure of riprap and then decrees of riprap stability

PRINTO/PRES international website for families of children with rheumatic diseases: www.pediatric-rheumatology.printo.it

Methods: Firstly, paediatric rheumatology centres and family self help associations were surveyed to characterise current clinical practice of physicians providing care for children with PRD, research activities, and training facilities of each centre. Secondly, international consensus was reached on the content of the website. Finally, the website was developed and the texts translated. Results: The web page contains three main sections: (a) description for families of the characteristics of 15 PRD; (b) list of paediatric rheumatology centres; (c) contact information for family self help associations. A version for 45 countries in 52 languages (with another three in progress) is now available on the web. 291 surveys from 171 centres and 102 family associations were received from 42 countries. The median proportion of time spent in paediatric practice in the centres examined was 100%, with 70% of this time dedicated to paediatric rheumatology. 90% of the centres were willing to perform clinical trials in the future. Conclusions: The PRINTO/PRES website provides a well defined and competent set of information about PRD, with appropriate multiple translated versions and easy web navigational direction

Mathematical Models of Vitreous Humour Dynamics and Retinal Detachment

The vitreous humour is a gel-like substance, which fills the vitreous chamber at the posterior part of the eye. It is a clear transparent material that can be mechanically characterised as a visco-elastic fluid. The vitreous has the important role of holding the retina in contact with the retinal pigment epithelium. During vitreous motion vitreoretinal tractions are generated and this might potentially lead to retinal detachment (RD). Studying the vitreous mechanical behaviour is thus relevant for understanding the physiology and pathophysiology of the eye. Mathematical modelling has provided significant contributions into understanding vitreous dynamics and the role it has on the occurence of vitreoretinal pathologies. In this chapter we first discuss works addressing vitreous motion induced by eye rotations and the possible generation of large mechanical stresses on the retina. Secondly we discuss models associated with RD, focusing on the progression of rhegmatogenous RD and the formation of exudative RD