Determination of the Composition of Substances Migrating from Plugs Based on Bromo-Butyl Rubber into Infusion and Injection Preparations

2020 ◽  
Vol 869 ◽  
pp. 135-139
Author(s):  
Yuri N. Khakimullin ◽  
Larisa Yuryevna Zakirova ◽  
Alfred D. Khusainov
Keyword(s):  
Inorganic Compounds ◽  
Experimental Studies ◽  
Atomic Emission ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Standard Glass ◽  
Volatile Organic ◽  
Pass Through ◽  
Direct Acting

The results of experimental studies of the composition of individual substances migrating from medical rubber plugs produced both in and abroad based on technical bromobutyl rubber are presented. The quantitative content of volatile organic compounds related to species impurities of gasoline was determined by gas chromatography from a standard glass bottle sealed with a sterile stopper based on bromobutyl rubber. The method of atomic emission spectroscopy was used to determine (indirect) the presence of organometallic, organosulfur and metal-inorganic compounds that did not pass through chromatographic columns, and the presence of organometallic, organosulfur and metal-inorganic compounds was determined by the content of metal and non-metal cations. The results of mass spectral studies of extracts of aqueous extracts from plugs based on bromobutyl rubber showed that they contain impurities of bromo-alkanes and bromo-arenes, which are direct-acting carcinogens.

scholarly journals Volatile Organic Compounds Of Hybrid Rugosa Roses In Latvia

2015 ◽  
Vol 69 (1-2) ◽  
pp. 57-61 ◽  
Author(s):  
Anta Sparinska ◽  
Nils Rostoks
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Solid Phase ◽  
Climatic Conditions ◽  
Mass Spectral ◽  
Baltic Sea Region ◽  
Volatile Organic ◽  
The Baltic ◽  
Spectral Libraries

Abstract Hybrid Rugosa is the most winter hardy group of roses in the climatic conditions of the Baltic Sea region. This study aimed at identifying new qualities of Hybrid Rugosa by focusing on determination of content of volatile organic compounds of flower petals and in hydrosols produced from these. Volatiles of seven cultivars were extracted using solid phase microextraction (SPME) with subsequent separation by gas chromatography. Identification was made by comparison with mass spectral libraries and by calculating linear retention indexes and comparing them with literature data. Twenty-five volatile aroma compounds were identified in the petals and hydrosols of six Hybrid Rugosa and species. Among those, phenylethylalcohol, ß-citronellol, geraniol and nerol were predominant. Species Rosa rugosa and variety ‘Plena’ showed the highest total level of volatiles and contained 26% and 31% ß-citronellol, respectively. Varieties ‘Raita’ and ‘Sniedze’ contained up to 57% citronellol. The main volatile compounds were detected in hydrosols in the same proportions, but their concentration was higher than in petals. The varieties ‘Raita’ and ‘Violeta’, bred in Latvia, are recommendable for use as a source of hydrosol.

Mass spectral studies of 3,5-Diamino-1,2,4-thiadiazoles

1977 ◽  
Vol 30 (3) ◽  
pp. 563 ◽  
Author(s):  
CP Joshua ◽  
KN Rajasekharan
Keyword(s):  
Electron Impact ◽  
Structure Determination ◽  
Mass Spectra ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Fragmentation Mechanisms

The mass spectra and fragmentation mechanisms of some 5-alkyl(or aryl)amino-3-amino-, 5-amino-3- arylamino-, 3,5-bis(arylamino)-, 4- aryl-3-arylamino-5-imino-4,5-dihydro-, and 3-alkyl(or aryl)amino-4- aryl-5-arylimino-4,5-dihydro-1,2,4-thiadiazoles and those of a 3-amino- 4-aryl-5-imino-4,5-dihydro-1,2,4-thiadiazole are discussed. The study, based on the behaviour of isomers under electron impact, attempts to evaluate the usefulness of mass spectra in structure determination of variously substituted 3,5-diamino-1,2,4-thiadiazoles.

Improvement Of Curvilinear Diagrams Of Concrete Deformation

2019 ◽  
pp. 99-104
Keyword(s):  
Reinforced Concrete ◽  
Peak Load ◽  
Experimental Studies ◽  
Concrete Structures ◽  
Deformation Model ◽  
Reinforced Concrete Structures ◽  
Significant Difference ◽  
Deformation Diagrams

Problems when calculating reinforced concrete structures based on the concrete deformation under compression diagram, which is presented both in Russian and foreign regulatory documents on the design of concrete and reinforced concrete structures are considered. The correctness of their compliance for all classes of concrete remains very approximate, especially a significant difference occurs when using Euronorm due to the different shape and sizes of the samples. At present, there are no methodical recommendations for determining the ultimate relative deformations of concrete under axial compression and the construction of curvilinear deformation diagrams, which leads to limited experimental data and, as a result, does not make it possible to enter more detailed ultimate strain values into domestic standards. The results of experimental studies to determine the ultimate relative deformations of concrete under compression for different classes of concrete, which allowed to make analytical dependences for the evaluation of the ultimate relative deformations and description of curvilinear deformation diagrams, are presented. The article discusses various options for using the deformation model to assess the stress-strain state of the structure, it is concluded that it is necessary to use not only the finite values of the ultimate deformations, but also their intermediate values. This requires reliable diagrams "s–e” for all classes of concrete. The difficulties of measuring deformations in concrete subjected to peak load, corresponding to the prismatic strength, as well as main cracks that appeared under conditions of long-term step loading are highlighted. Variants of more accurate measurements are proposed. Development and implementation of the new standard GOST "Concretes. Methods for determination of complete diagrams" on the basis of the developed method for obtaining complete diagrams of concrete deformation under compression for the evaluation of ultimate deformability of concrete under compression are necessary.

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