Morphological Analysis of Unstructured and Prestructured Magneto-rheological Elastomer

By providing or not put on a magnetic flux, a magneto rheological (MR) elastomer becomes a very powerful and advanced smart material that could be twisted and responded hurriedly in relations of mechanical strength. They are elastomer materials with embedded iron elements in an elastomer environment. Isotropic(unstructured) and anisotropic(prestructured) MR elastomers are categorized built on the submission of a magnetic flux during in the fabrication process. The scattering of magnetizable elements in the medium of an elastomer is well defined and arranged by kind. Scanning Electron Microscopy(SEM) had revealed their shape. They should be employed in a variability of solicitations payable to their improved morphological characteristics, such as pulsation absorbers, isolators, seismic devices, and so on. Keywords: Smart material, magneto rheological elastomer, carbonyl iron particles, morphology, scanning electron microscopy

The Influence of Self-Heating Iron on the Thermal, Mechanical, and Swelling Properties of PDMS Composites for Organic Solvents Removal

Volatile organic compounds pollute the environment and pose a serious threat to human health due to their toxicity, mutagenicity, and carcinogenicity. In this context, it is highly desirable to fabricate high-performance poly (dimethylsiloxane) (PDMS) composites to remove organic solvents from the environment using a simple technique. Therefore, in the present study, Fe-PDMS composites were fabricated using a technique based on magnetic induction heating with iron particles serving as a self-heating agent. Under an alternating magnetic field, the iron particles served as a thermal source that assisted in the progression of PDMS crosslinking. The influence of self-heating iron on the properties of the fabricated Fe-PDMS composites was also investigated. The hydrosilation reaction occurring during the crosslinking process was controlled using FT-IR. The heating efficiency of PDMS 1, PDMS 2, and PDMS 3 was studied as the function of induction time (0–5 min) and the function of iron content (0%, 1%, and 30% wt.%). The results revealed that the mechanical properties of the PDMS 2 composite were enhanced compared to those of the PDMS 1 and PDMS 3 composites. The mechanical properties of PDMS 3 were the least efficient due to cluster formation. PDMS 3 exhibited the highest thermal stability among all composites. Furthermore, the swelling behavior of different materials in various organic solvents was studied. PDMS was observed to swell to the greatest extent in chloroform, while swelling to a large extent was observed in toluene, pentane, and petroleum ether. PDMS swelling was the least in n-butanol. The elastomeric behavior of crosslinked PDMS, together with its magnetic character, produces stimuli-responsive magneto-rheological composites, which are quite efficient and suitable for applications involving the removal of organic solvents.

Mitigation of Iron Irradiation-Induced Genotoxicity and Genomic Instability by Postexposure Dietary Restriction in Mice

Background and Purpose. Postexposure onset of dietary restriction (DR) is expected to provide therapeutic nutritional approaches to reduce health risk from exposure to ionizing radiation (IR) due to such as manned space exploration, radiotherapy, or nuclear accidents as IR could alleviate radiocarcinogenesis in animal models. However, the underlying mechanisms remain largely unknown. This study is aimed at investigating the effect from postexposure onset of DR on genotoxicity and genomic instability (GI) induced by total body irradiation (TBI) in mice. Materials and Methods. Mice were exposed to 2.0 Gy of accelerated iron particles with an initial energy of 500 MeV/nucleon and a linear energy transfer (LET) value of about 200 keV/μm. After TBI, mice were either allowed to free access to a standard laboratory chow or treated under DR (25% cut in diet). Using micronucleus frequency (MNF) in bone marrow erythrocytes, induction of acute genotoxicity and GI in the hematopoietic system was, respectively, determined 1 and 2 months after TBI. Results and Conclusions. TBI alone caused a significant increase in MNF while DR alone did not markedly influence the MNF. DR induced a significant decrease in MNF compared to the treatment by TBI alone. Results demonstrated that postexposure onset of DR could relieve the elevated MNF induced by TBI with high-LET iron particles. These findings indicated that reduction in acute genotoxicity and late GI may be at least a part of the mechanisms underlying decreased radiocarcinogenesis by DR.

Genesis and evolution of magmas according to data on hot heterogeneous accretion of the Earth

The obtained numerous proofs of hot heterogeneous accretion of the Earth lead to a fundamentally new solution to the problems of genesis and evolution of magmas. According to these data, the Earth’s core was formed earlier than the silicate mantle as a result of the agglutination of iron particles of the protoplanetary disk under the influence of magnetic forces, because with a small body size, these forces were billions of times more powerful thangravitational ones. The accretion of the silicate mantle created a global magmatic ocean under the influence of impact heat release. Its bottom part crystallized and fractionated as a result of the pressure increase of the formed upper parts. Cumulates formed the ultrabasic mantle, and residual melts formed the magmatic ocean. The increase in ocean temperature and depth caused the evolution of bottom residual melts from acidic to ultrabasic, the appearance of corresponding layers in the ocean, and the reverse geothermal gradient in the mantle. As a result of the cooling and crystallization of the ocean from top to bottom after 3.8 billion years ago early Precambrian crystal complexes, acidic crust, and the lithosphere of ancient platforms were formed. The separation of residual melts from various layers caused the evolution of magmatism on them from acidic to akaline-ultramafic and kimberlite. Heating of the mantle by a high-temperature core led to the appearance of a direct geothermal gradient at the end of the Proterozoic, convection in the mantle, and modern geodynamic environments. In them, magmas are formed by the frictional and decompression melting of the differentiates of the magmatic ocean.