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The development of environmentally friendly and cost-effective lubricating materials to reduce friction and wear at the macroscale is crucial for reducing fuel consumption and exhaust emissions, thereby enhancing sustainability. Deep eutectic solvents (DESs) have emerged as viable alternatives to traditional lubricants due to their ease of preparation, affordability, reproducibility, and superior tribological properties. Herein, a series of natural ternary DESs (TDESs) are successfully developed by blending eco-friendly and economical D -sorbitol and ethanolamine with quaternary ammonium salts through hydrogen bond interactions that may be regarded as a new and green liquid lubricating system. The synthesized TDESs exhibit exceptional thermal stability, rheological properties, corrosion resistance, and wettability towards metallic substrates. Moreover, the experimental results combined with molecular dynamics simulations indicate that the TDESs can form a robust protective lubricating film on steel surfaces through polar adsorption and tribochemical reactions. Consequently, the synthesized TDESs demonstrate a low friction coefficient (∼0.1) and ultra-low wear rate (as low as 7.8 × 10−10 mm3 N−1 m−1), exhibiting a near-zero wear behavior on steel surfaces under high load (100 N) and multi-environment scenarios. This research not only highlights the potential applications of DESs in tribology but also provides guidance for the future generation of green and high-performance liquid lubricating materials. [ABSTRACT FROM AUTHOR]

Axial piston pumps with compact structures and high efficiency are widely used in construction machinery. The efficiency and lifetime strongly depend on the tribological performance of the pump's valve plate pair. To enhance the tribological performance of the valve plate pair, surface textures, and H-DLC coatings were fabricated to modify the CuAl10Fe5Ni5 surfaces. The influences of elliptic textures of different sizes and textured H-DLC coatings on the surface friction and wear properties of the valve plate surface under oil lubrication were evaluated using a ring-on-disk tribometer. The results reveal that the friction and wear properties of the CuAl10Fe5Ni5 surfaces are significantly enhanced by elliptic textures, and the friction coefficient and wear rate of textured CuAl10Fe5Ni5 with E90 are maximally decreased by 95% and 87%, respectively. Compared with the surface textures and H-DLC coatings, the textured H-DLC coating has the greatest ability to reduce wear and adhesion. The wear rate of the textured H-DLC coating is further reduced by 98%. This improvement can be explained by the synergistic effect of the elliptic textures and H-DLC coatings, which are attributed to the reduced contact area, debris capture, and secondary lubrication of the elliptic textures, and increased surface hardness. [ABSTRACT FROM AUTHOR]

Xinjiang Qitai is constructing a 110-m fully steerable radio telescope (QiTai radio Telescope [QTT]) equipped with a phased array feeds (PAF) receiver, which will install the focal plane operating from 0.7 to 1.8 GHz. In this article, we introduce a PAF receiver model for beamforming, and the numerical model of the internal and external noise for this PAF receiver is provided using electromagnetic field simulation software. The linear constraint minimum variance (LCMV) algorithm is used to simulate the interference mitigation. The interference mitigation rate is from 0.581 to 0.921, and the signal restoration rate is from 0.998 to 1.512 within the error range of an interference arrival angle of 10°. This conclusion can be used in the signal correction of the PAF receiver for interference mitigation. [ABSTRACT FROM AUTHOR]

A superelastic self–healing eutectogel was designed and prepared using poly (vinyl alcohol) (PVA) as the bulk skeleton material, while silk fibroin (SF) and two–dimensional (2D) MXene (Ti3C2TX) as reinforcing fillers. In brief, the eutectogel possesses a high tensile strength of 7.63 MPa, and its elongation at break reached 1115.2%, higher than most reported polymers (<1000%). In addition, the eutectogel–assembled sensor has a high ionic conductivity of 0.61 S/m and a high strain sensitivity of 5.17 kPa−1. Moreover, eutectogel shows excellent self–healing ability and can achieve self–healing quickly within 10 min, while its tensile strength and elongation at break can be restored to 84.7% and 97.4% of the initial levels. Besides, a stable electrical signal can be transmitted after 200 cycles at 30% strain. Finally, the eutectogel can withstand various environmental conditions, such as atmospheric or even vacuum evaporation and low–temperature freezing, while maintaining good mechanical and sensing performances. The assembled flexible sensors based on the eutectogel demonstrate their significant application prospects in wearable devices, especially human physiological monitoring. [ABSTRACT FROM AUTHOR]

The semi-autogenous grinding system consisting of semi-autogenous mill (SAG mill) and ball mill is widely used, but the load imbalance between the semi-autogenous mill and the ball mill often occurs in operation. The reasons of load imbalance and proposes optimization measures with an example of a copper mine project have been analyzed. The main optimization measures include: optimizing the feed size of the semi-autogenous mill, adjusting the discharge product size of the semi-autogenous mill by increasing the lattice hole slit and opening rate, optimization of the screen slit size, modifying the straight lattice plate to curved lattice plate, optimizing the return path of crushed stubborn stone, etc. The new feed capacity of the semi-autogenous mill system is increased from 39 960 t/d to 42 500 t/d, while the semi-autogenous mill power remains unchanged. But the ball mill operating power is increased from 9 300 kW to 11 000 kW, resulting in a more reasonable load distribution between the semi-autogenous mill and the ball mill. Through the analysis and application of different optimization measures, this study provides inspiration and reference to solve load imbalance problems in semi-autogenous grinding process of other mines. [ABSTRACT FROM AUTHOR]

Wetlands play a key role in maintaining ecological balance and climate regulation. However, due to the complex and variable spectral characteristics of wetlands, there are no publicly available global 30-meter time-series wetland dynamic datasets at present. In this study, we present novel global 30 m annual wetland maps (GWL_FCS30D) using time-series Landsat imagery on the Google Earth Engine platform, covering the period of 2000–2022 and containing eight wetland subcategories. Specifically, we make full use of our prior globally distributed wetland training sample pool, and adopt the local adaptive classification and spatiotemporal consistency checking algorithm to generate annual wetland maps. The GWL_FCS30D maps were found to achieve an overall accuracy and Kappa coefficient of 86.95 ± 0.44% and 0.822, respectively, in 2020, and show great temporal variability in the United States and the European Union. We expect the dataset would provide vital support for wetland ecosystems protection and sustainable development. [ABSTRACT FROM AUTHOR]

Previous studies on global carbon emissions from forest loss have been marked by great discrepancies due to uncertainties regarding the lost area and the densities of different carbon pools. In this study, we employed a new global 30 m land cover dynamic dataset (GLC_FCS30D) to improve the assessment of forest loss areas; then, we combined multi-sourced carbon stock products to enhance the information on carbon density. Afterwards, we estimated the global carbon emissions from forest loss over the period of 1985–2020 based on the method recommended by the Intergovernmental Panel on Climate Change Guidelines (IPCC). The results indicate that global forest loss continued to accelerate over the past 35 years, totaling about 582.17 Mha and leading to total committed carbon emissions of 35.22 ± 9.38 PgC. Tropical zones dominated global carbon emissions (~2/3) due to their higher carbon density and greater forest loss. Furthermore, global emissions more than doubled in the period of 2015–2020 (1.77 ± 0.44 PgC/yr) compared to those in 1985–2000 (0.69 ± 0.21 PgC/yr). Notably, the forest loss at high altitudes (i.e., above 1000 m) more than tripled in mountainous regions, resulting in more pronounced carbon emissions in these areas. Therefore, the accelerating trend of global carbon emissions from forest loss indicates that great challenges still remain for achieving the COP 26 Declaration to halt forest loss by 2030. [ABSTRACT FROM AUTHOR]

Copper is an indispensable metal in the new energy era. In order to efficiently develop a low-grade copper ore resource abroad, in view of the important role of process mineralogy in the selection of ore dressing process, the process mineralogy of this ore was studied by using the testing and analysis techniques such as MLA and optical microscope, and important process mineralogy data were obtained, which guided the determination of beneficiation process in the concentrator. The results show that the main metal sulfides in the ore are chalcopyrite and pyrite, and the gangue minerals are mainly quartz and potassium feldspar, followed by muscovite, albite and biotite. Chalcopyrite is basically the copper bearing minerals, and there are a small amount of (blueschene) chalcocite and other copper bearing minerals. Under the condition of -- 74 µm accounting for 62%, chalcopyrite has a good dissociation condition, uniform particle size distribution, and most of them are concentrated in the size range conducive to flotation recovery. Under the separation treatment of three roughing, regrinding of coarse concentrate, classification, three cleaning and one fine cleaning, when the raw ore contains 0.41% copper and 0.24 g/t gold, a copper concentrate containing 20.83% copper and 9.25 g/t gold with copper recovery of 90.43% and gold recovery of 68.60% can be obtained. The efficient exploitation and utilization of low-grade gold-bearing copper sulfide ore resources are realized. [ABSTRACT FROM AUTHOR]

Macromol. Mater. Eng. 2024, 309, 2300273In the list of authors at the beginning of the article, we misspelled the name of the first author as "Jinqin Wang", which is incorrect.The correct spelling should be "Jinqing Wang".We apologize for this error.The first author's first name has been corrected in the article itself: https://doi.org/10.1002/mame.202300273By Jinqing Wang; Cheng Yao; Xinghua Huang; Qin Zhang and Ke WangReported by Author; Author; Author; Author; Author [Extracted from the article]

With the excavation of landfill sites, the disposal and reduction of organic-rich soils with high proportions of heavy metals have become urgent issues. This study focuses on the pollution characteristics and ecological risks associated with heavy metals in the humus soil of a municipal solid waste (MSW) landfill. The results indicate that the concentrations of heavy metals in the humus soil followed the sequence of Cu > Zn > Cr > Pb > Ni > As > Cd > Hg, and Cu and Cd exhibited the highest exceedance multiples. Except for Cr, the concentrations of the heavy metals in the humus soil were higher than those in combustible components, with a strong Hg correlation. Heavy metal forms indicate varying degrees of mobility and stability; Cr, As, Hg, and Pb were stable, while Ni, Cd, Cu, and Zn showed higher mobility. The results of the principal component analysis reveal that heavy metals primarily originate from industrial and agricultural waste. Finally, the geoaccumulation index of the metals indicated that Cu, Zn, Cd, and Pb exhibited severe contamination. Most importantly, Cd posed the greatest environmental risk as it has the highest effective content, bioavailability, and mobility. This study provides a scientific foundation for mitigating heavy metal pollution in the humus soil of landfill sites. [ABSTRACT FROM AUTHOR]

A superelastic self-healing eutectogel was designed and prepared using poly (vinyl alcohol) (PVA) as the bulk skeleton material, while silk fibroin (SF) and two-dimensional (2D) MXene (Ti 3 C 2 T X ) as reinforcing fillers. In brief, the eutectogel possesses a high tensile strength of 7.63 MPa, and its elongation at break reached 1115.2%, higher than most reported polymers (<1000%). In addition, the eutectogel-assembled sensor has a high ionic conductivity of 0.61 S/m and a high strain sensitivity of 5.17 kPa -1 . Moreover, eutectogel shows excellent self-healing ability and can achieve self-healing quickly within 10 min, while its tensile strength and elongation at break can be restored to 84.7% and 97.4% of the initial levels. Besides, a stable electrical signal can be transmitted after 200 cycles at 30% strain. Finally, the eutectogel can withstand various environmental conditions, such as atmospheric or even vacuum evaporation and low-temperature freezing, while maintaining good mechanical and sensing performances. The assembled flexible sensors based on the eutectogel demonstrate their significant application prospects in wearable devices, especially human physiological monitoring., (© 2024 Wiley-VCH GmbH.)