Paleoenvironmental conditions during deposition of Kolosh and Gercus formations in northern Iraq as deduced from clay mineral distributions

A mineralogical study using X-ray diffraction supported by scanning electron microscopic examination on the Paleocene- Eocene Kolosh and Gercus formations from northern Iraq is conducted to show the distribution of clay minerals and their paleoenvironmental implications. Smectite palygorskite, kaolinite, illite, and chlorite are commonly present in varying proportions within the Kolosh and Gercus formations. Association of smectite and chlorite in the claystone of the Paleocene Kolosh Formation refers to marine environment of this formation, whereas development of palygorskite fibers from smectite precursor may relate to post-depositional diagenesis. In addition, the abundance of illite and kaolinite in the Eocene Gercus Formation suggests a greater influence of terrigenous input in humid conditions, affecting the distribution of these clay minerals. The study shows vertical change in clay minerals distribution when illite and kaolinite dominate in the Eocene Gercus Formation, in comparison to chlorite and smectite abundance in the Paleocene Kolosh Formation which may relate to global warming in the Eocene.

Inhibiting wood-water interactions by hydrothermal hemicellulose extraction combined with furfurylation

Wood-water interactions affect durability and performance of wood products, such as dimensional stability and biodegradation. To upgrade wood, a combined modification via hemicellulose extraction and furfurylation was proposed to inhibit wood-water interactions. More intense hemicellulose extraction caused larger voids and led to higher pore volume. The increment of porosity resulted in more uniform distribution of polymerized furfural resin in cells, as indicated by scanning electron microscopic and confocal laser scanning microscopic observations. The combined modification greatly reduced surface wettability with an increase of water contact angle (CA) of over 134% at 100 s. With hemicellulose extraction, polymerized furfural resin partially occupied the accommodation initially for water molecules and reduced accessible sorption sites, causing water absorption (WA) of wood to decrease by over 30% after soaking in water for 768 h. Dynamic moisture sorption was weakened after combined modification, and the moderate hemicellulose extraction combined with furfurylation reduced the moisture content by over 50% due to incorporative changes of chemical sorption sites and physical porosity. The results confirmed the efficiency of the combined modification in inhibiting wood-water interactions and indicated the importance to accurately control hemicellulose content during modification. This study could provide useful information for sustainably enhancing wood performance and upgrading low-quality wood.

Boriding of Laser-Clad Inconel 718 Coatings for Enhanced Wear Resistance

Nickel-based superalloys are particularly suitable for applications under corrosive conditions. Economic advantages can be achieved by limiting the use of materials to the surface region. Furthermore, the tribological property profile can be significantly improved by surface hardening. In the present study, the possibility of a process combination comprising a coating and a surface hardening technology was investigated. For this purpose, Inconel 718 coatings were applied to austenitic stainless steel by laser cladding. Subsequently, a thermochemical surface hardening by boriding was carried out. Scanning electron microscopic (SEM) examinations were performed to evaluate the microstructure. The phase composition was determined by means of X-ray diffraction (XRD) for the different states of the coating system. The influence of thermochemical hardening was investigated for different wear conditions. The increase in microhardness and wear resistance clearly demonstrates the utilization potential of the presented process combination.

Multi-Independent Optimization while Turning of Inconel-600 alloy using Grey Interactive Exploration

This investigation effort offers multi-quality attributes optimization while turning of Inconel-600 superalloy. Taguchi's L9 orthogonal planning is implemented to review the upshot of governing aspects such as machining speed, feed rate, and depth of cut on vibrations and surface roughness (SR). To heighten all the three leading variables, the grey interactive exploration (GIE) is implemented. The grey interactive rating (GIR) is practiced as a multi-quality exclusive key (MQEK). The finest formation of central variables acquired from the investigational grades is cutting speed 500 m/min, feed rate 0.22 mm/rev and depth of cut 0.5 mm. ANOVA scrutiny signposts that feed rate is a crucial variable relating to the superiority yields. Products of endorsement pilots display that the ideal foremost variables developed the grey interactive rating from 0.6932 to 0.8138 for the numerous retorts. Scanning Electron Microscopic (SEM) scrutiny of cutting tool spectacles that fracture, chipping, abrasion and adhesion are the primary wear phenomena.