Health effects of trans fatty acids (TFAs) on human organisms can vary according to their type, structure, composition, and origin. Even though the adverse health effects of industrial TFAs (iTFAs) have been widely discussed, the health effects of natural TFAs (nTFAs) are still questionable. Hence, it is important to review the literature and provide an overall picture on the health effects of different TFAs coming from industrial and ruminant sources, underlining those types that have adverse health effects as well as suggesting methods for reducing their harmful effects. Multiple databases (PubMed, Medline, Cochrane Library, etc.) were searched with the key words “trans fatty acid sources”, “ruminant”, “industrial”, “conjugated trans linoleic acid”, “human”, “coronary heart disease”, “cancer”, etc. Reference lists of the studies were scanned discussing the health effects of iTFAs and nTFAs. The review of the literature showed that iTFAs are found to be more harmful than ruminant-produced nTFAs. Although several beneficial effects (such as reduced risk of diabetes) for nTFAs have been observed, they should be used with caution. Since during labeling it is usually not mentioned whether the TFAs contained in food are of industrial or natural origin, the general suggestion is to reduce their consumption.

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The possibility of partial or complete replacement of PbO in fusible glass solders by less toxic components is investigated. It is found that it is impossible to find a full-fledged replacement for glasses in the lead-borate eutectic, used as the glass base in glass soldering compositions for sealing glass ceramic packages of integrated microcircuits at temperatures 390 -420°C, within the systems PbO -P 2 O 5 -ZnO -B 2 O 3 , V 2 O 5 -P 2 O 5 -ZnO -B 2 O 3 , and TeO 2 -PbO -V 2 O 5 -Bi 2 O 3 with different additives and total mass content of class-I hazard components not exceeding 70%.Integrated microcircuits are ordinarily assembled in metal, plastic, cermet, or glass ceramic packages. The latter have a number of advantages: manufacturability and low cost as compared with cermet packages and mechanical and dielectric properties as compared with plastics and, in part, metal packages. In addition, microcircuits assembled in cermet packages are hermetic, reliable, and long-lasting.The technical-operational characteristics of the cermet packages of integrated microcircuits are largely determined by the properties of the glass solders used to glue the ceramic parts and the metal leads of the microcircuits in a hermetic case. In this connection the glass solder must form a mechanically strong and chemically stable vacuum-tight dielectric layer between the parts of the package and the leads of the microcircuits at a prescribed temperature.The main characteristics of the glass solders are the volume resistivity r, permittivity e, CLTE, and sealing temperature. The higher r and the lower e of the glass solder, the more the leads can be placed per unit surface area of a package and therefore the size and mass of a device can be decreased to the maximum extent possible for its prescribed functional possibilities. Modern electronic devices often operate with sharp temperature differentials, so that the microcircuits must possess a high heat resistance. This condition can be satisfied if the CLTE of the glass solder, the ceramic base of the package, and metal leads of the microcircuits are all compatible with one another. Microcircuit indicators such as the maximum working temperature and the operational stability and service life are temperature dependent, and these dependences are largely contradictory. Thus, to increase the working temperature it is best to use refractory glass solders, but high sealing temperatures are a source of thermionic emission of electrons, which greatly decreases reliability, stability and service life of microcircuits. In this connection a sealing temperature of 390 -420°C is considered to be optimal.The most suitable glass bases meeting the indicated requirements are obtained with a lead-borate eutectic (85% 3 PbO, 15% B 2 O 3 ) base [1 -3]. The deformation onset temperature of the glasses synthesized in this system are t d.o = 305 -350°C, CLTE -(100 -115)´10 -7 K -1 , surface crystallization near the sealing temperature (400 -450°C) -1 -15%, r at 150°C -to 10 11 W × cm and e -18 -19. With cryst...

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