Search

The low strength caused by the single FCC structure of the CrMnFeCoNi high entropy alloy (HEA) limits its application in the field of coating. Here, we prepared high-entropy alloy coatings of CrMnFeCoNi with different ZrC contents on Q235 steel by a plasma transferred arc process. The effects of ZrC on the microstructure and properties of the CrMnFeCoNi HEA coating were investigated by optical microscopy, scanning electron microscope, and X-ray diffraction and by employing a potensiostat/galvanostat. The results showed that ZrC mainly existed in the coatings as a second phase, having little influence on the main crystal structure and micromorphology of the CrMnFeCoNi HEA coating. The hardness of the CrMnFeCoNi HEA coating increased with the ZrC content. ZrC can effectively improve the corrosion resistance of the CrMnFeCoNi HEA coating. In a 1 mol/L NaCl solution with 4 wt% ZrC, the annual corrosion rate was only 5.997% of that of the HEA coating. Nevertheless, the improvement in the wear resistance of CrMnFeCoNi high-entropy alloy coatings was not apparent with the addition of ZrC. Consequently, the addition of ZrC to the FeCoCrNiMn high-entropy alloy coating holds promise for applications in corrosion resistance, particularly in oceanic environments. [ABSTRACT FROM AUTHOR]

Presents a study on the late pleistocene shallow-water marine sediments in the Fildes Peninsula collected during a 1993 expedition. Identification of 17 species of foraminifera; Analysis of grain size; Details on the findings of the study.

Land subsidence due to consolidation of sediment was analyzed in the Yellow River delta, using lithological data of deposits, equations of soil mechanics, and empirical relations. Subsidence in an abandoned deltaic lobe largely results from the consolidation of deltaic clay layers accumulated in the prodelta, the bays, and marine clay layers underlying the delta. The prodelta and marine clay layers have a total thickness of approximately 14 m. In the areas where thick bay-clay layers accumulated on the prodelta-clay layers, the total thickness of the clay can reach 20 m. Calculations show that after 15-m-thick deltaic strata were deposited on the seabed, the total consolidation of the 14-m-thick clay layers is approximately 1.44 m and 1.52 m for the 20-m-thick clay layers. After the first 40 years, the rate of land subsidence resulting from consolidation of the 14-m-thick clay layers will decrease gradually to 0.005 m/y. For the 20-m-thick clay layers, it will take 57 years for the rate of subsidence to decrease to 0.005 m/y. [ABSTRACT FROM AUTHOR]

In the east of Xiaolangdi, many river terraces are developed at the exit of the Yellow River Gorges. Among them the terraces in Kouma, Yanshi of Henan Province are most typical, where the Yellow River developed three staircase terraces, among which the altitude of gravel stratum of the topmost terrace is 30-35 m higher than the river level. The top of the gravel stratum was covered by 60 m eolian loess deposits which have many brownish-red paleosol strips. And the paleosol S14 is at its bottom. Research on systematic magnetostratigraphy and paleosol-loess matching indicates that the bottom age of the loess on the topmost terrace is 1165 ka. Therefore, it can be concluded that the terrace develops no later than 1.165 Ma and the situation that the Yellow River runs through Sanmen Gorges and inpours into East China Sea happened at least before 1.165 Ma. [ABSTRACT FROM AUTHOR]

Presents a study on the age of the clastic-clay sediments with varied content of carbonate in core TS95 taken from the Lake Tianshuihai in the northwest of the Tibetan Plateau using the total sample dissolution (TSD) U-series isochron method. Geographical and geological settings in the research region; Basic principles choosing TSD U-series isochron dating method; Methods and procedures; Results.

Focuses on a study which examined geochemical indexes, using R/S analyses, to calculate climatic and environmental evolution around the Tianshuihai Lake at the West Kunlun Mountain in China. Geochemical changes in the area; Application of the R/S analysis; Soil variations in Tianshuihai area; Methodology and results.