К вопросу состава гранатов во вмещающих породах и рудах месторождения Эльдорадо

На основании изучения гранатов во вмещающих породах и рудах месторождения Эльдорадо сделан вывод о том, что формирование его происходило на фоне падающих температур и давлений

Disorder control in crystalline GeSb2Te4 and its impact on characteristic length scales

Crystalline GeSb2Te4 (GST) is remarkable material, as it allows to continuously tune the electrical resistance by orders of magnitude without involving a phase transition or stoichiometric changes, just by altering the short-range order. While well-ordered specimen are metallic, increasing amounts of disorder can eventually lead to an insulating state with vanishing conductivity in the 0K limit, but a similar number of charge carriers. These observations make disordered GST one of the most promising candidates for the realization of a true Anderson insulator. While so far the low-temperature properties have mostly been studied in films of small grain size, here a sputter-deposition process is employed that enables preparation of a large variety of these GST states including metallic and truly insulating ones. By growing films of GST on mica substrates, biaxially textured samples with huge grain sizes are obtained. A series of these samples is employed for transport measurements, as their electron mean free path can be altered by a factor of 20. Yet, the mean free path always remains more than an order of magnitude smaller than the lateral grain size. This proves unequivocally that grain boundaries play a negligible role for electron scattering, while intragrain scattering, presumably by disordered vacancies, dominates. Most importantly, these findings underline that the Anderson insulating state as well as the system's evolution towards metallic conductivity are indeed intrinsic properties of the material

Zerebraler Befall mit Parvovirus B19 beim plötzlichen Säuglingstod?

Die Ursache des plötzlichen Säuglingstodes (SIDS) konnte trotz Herausarbeitens von Risikofaktoren noch nicht geklärt werden. Diskutiert werden Infektionen, die sich durch Beteiligung verschiedener Organe negativ auf den Gesamtzustand des Kindes auswirken, sowie eine mögliche Beeinträchtigung der zentralen Atem-/Kreislaufregulation. Die vorliegenden Arbeit untersucht, inwieweit das Parvovirus B19 durch cerebralen Befall am Tod der Kinder beteiligt sein könnte. Es wurden 23 SIDS-Fälle und 7 Fälle mit anderer Todesursache untersucht, indem die aus jeweils 4 Hirnarealen extrahierte DNA mittels PCR auf das Vorhandensein von Parvovirus B19-Genom getestet wurde. Als Positivkontrolle diente die DNA eines an PV B19-Myokarditis verstorbenen Jungen. Außer in der Positivkontrolle konnte man hierbei in keiner der DNA-Proben eine Inokulation des Virus nachweisen. Es ist daher nicht davon auszugehen, dass ein cerebraler Befall mit diesem Virus regelhaft am akuten Todesgeschehen beteiligt ist

Stoichiometry determination of chalcogenide superlattices by means of X-ray diffraction and its limits

In this paper we explore the potential of stoichiometry determination for chalcogenide superlattices, promising candidates for next-generation phase-change memory, via X-ray diffraction. To this end, a set of epitaxial GeTe/Sb2Te3 superlattice samples with varying layer thicknesses is sputter-deposited. Kinematical scattering theory is employed to link the average composition with the diffraction features. The observed lattice constants of the superlattice reference unit cell follow Vegard's law, enabling a straight-forward and non-destructive stoichiometry determination.Comment: physica status solidi (RRL) - Rapid Research Letters (2019

Оценка и выбор канала сбыта металлургического производства

This paper considers the problem of determining the distribution channels of metallurgicalproducts. The basis for the study was taken method of expert evaluations; the gist of it is that the expert willbe made comprehensive assessment of distribution channels for according to certain criteria. Based on estimatesof site contents, the system selects the most effective distribution channels

О методах расчета ?'-потенциала при наличии адсорбированных на электроде органических веществ

Проведено сравнение исходных посылок различных методов расчета ?'-потенциала и результатов расчета по этим методам для случая адсорбции на ртути ?-нафтола. Показано, что для адсорбирующихся веществ, меняющих ориентацию молекул относительно поверхности электрода лучшие результаты дает определение ?'-потенциала по сдвигу максимума электрокапиллярной кривой