The research development of the structure in a-Fe Microcrystals with the Orientation deformed by compression with different values of the friction coefficient

The paper analyzes the change in the dislocation structure in a-Fe microcrystals with orientations <100> and <110> deformed by compression under conditions of limited flow with different values of the friction coefficient. The orientation stability of the microcrystal and texture is investigated when the compression axis deviates from the normal to the compression plane. Shooting and analysis of limited pole figures made it possible to establish that the operation of the OSS in the MC with the [100](001) orientation at different values of the friction coefficient at the sample-punch interface leads to a rotation of the latticework relatively to the MC axis. The specific conditions of plastic deformation under compression determined by the MC morphology prohibit displacement deyz., as the deformation is observed under conditions of limited flow. The operation of the OSS, consequently, leads to the MC partition with the [100] (001) orientation deformed by compression with the friction coefficient Kmax into parts and the rotation of the latticework around the growth axis. It is established the connection between the friction coefficient at the crystal-punch interface and the sliding geometry in a-Fe MCs deformed by compression under conditions of limited flow. The authors carried out the dimension of the friction ratio has a significant effect on the slip geometry and the dislocation structure formed in the MC of the [100] orientation deformed by compression along the (001) plane. Changes in the friction coefficient and the angle deviation of the compression axis from the normal to the compression plane in the MC with the [100] (001) orientation do not affect the slip geometry and the dislocation structure formed during plastic deformation.

Nitrogen isotope sclerochronology - insights into coastal environmental conditions and Pinna nobilis ecology

&lt;p&gt;&lt;em&gt;Pinna nobilis&lt;/em&gt; is a large bivalve endemic to the Mediterranean Sea that lives in shallow coastal areas. Due to its size and relatively fast shell growth rates, it is an interesting taxon for high resolution geochemical and sclerochronological research. Subsequently to previous analyses of &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C in &lt;em&gt;P. nobilis&lt;/em&gt; shells, here, we investigate nitrogen isotopes in the carbonate-bound organic matrix (&amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt;) of this species. Our objectives were to test if &lt;em&gt;P. nobilis&lt;/em&gt; shells (i) can be used as an indicator of the isotopic baseline of the system, and (ii) is a good candidate for obtaining high-resolution temporal data on environmental &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N variability. Due to the multiple mass mortality events of &lt;em&gt;P. nobilis&lt;/em&gt; spreading throughout the Mediterranean, including the Adriatic Sea, we also tested if (iii) &lt;em&gt;P. nobilis&lt;/em&gt; geochemistry changes as a response to diseases.&lt;/p&gt;&lt;p&gt;Shells were opportunistically collected by skin diving from 4 shallow coastal localities in the eastern Adriatic, as a part of a project on mortality monitoring. Specimens from Lim channel (October 2019), Ka&amp;#353;tela Bay (January 2020) and Mali Ston Bay (November 2019) were collected alive, while in Pag Bay, shells of three recently dead specimens were collected in September 2020. Tissue and epibionts were removed and shells carefully cleaned and air-dried. Shell powder was collected by milling sample swaths by hand using a DREMEL Fortiflex drill equipped with a 300 &amp;#956;m tungsten carbide drill bit. For &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; analysis, three shells from each locality were processed and three replicas were collected from each of these shells by milling shallow lines parallel to the growth axis from the internal shell surface. In addition, high-resolution &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; data were obtained for one shell from Ka&amp;#353;tela by milling lines (N=40) perpendicular to the major growth axis from the external shell surface. From this shell we also collected shell powder for &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O&lt;sub&gt;shell&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;shell&lt;/sub&gt; analysis to enable placing &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; into temporal context. Isotope samples were analyzed Union College on an elemental analyzer - isotope ratio mass spectrometer.&lt;/p&gt;&lt;p&gt;Results indicate significant differences in &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; between sampling localities, with lowest values recorded for shells from Pag Bay (3.73&amp;#177;0.36&amp;#8240;), and highest for shells sampled in Lim channel (7.04&amp;#177;0.63&amp;#8240;). High-resolution &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; data obtained from the shell collected from Ka&amp;#353;tela Bay corresponded to a time interval from spring 2018 to spring 2019. These data showed relatively small variations (5.02&amp;#177;0.33&amp;#8240;). However, &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; values increased to 8.65&amp;#177;1.61&amp;#8240; closest to the shell margin, and were coupled with a decrease in &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;shell&lt;/sub&gt; values, indicating that this animal was experiencing stressful conditions several months prior to its death. According to our findings, &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;CBOM&lt;/sub&gt; values serve as an indicator of the isotopic baseline of the ecosystem as well as a potential powerful tool to study bivalve physiology.&lt;/p&gt;&lt;p&gt;Research was the supported by the Croatian Science Foundation, research project BivACME.&lt;/p&gt;

First principles calculation of structural, electronic and optical properties of (001) and (110) growth axis (InN)/(GaN)n superlattices

Based on the full potential linear muffin-tin orbitals (FPLMTO) calculation within density functional theory, we systematically investigate the electronic and optical properties of (100) and (110)-oriented (InN)/(GaN)n zinc-blende superlattice with one InN monolayer and with different numbers of GaN monolayers. Specifically, the electronic band structure calculations and their related features, like the absorption coefficient and refractive index of these systems are computed over a wide photon energy scale up to 20 eV. The effect of periodicity layer numbers n on the band gaps and the optical activity of (InN)/(GaN)n SLs in the both growth axis (001) and (110) are examined and compared. Because of prospective optical aspects of (InN)/(GaN)n such as light-emitting applications, this theoretical study can help the experimental measurements.