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This research studied layered zirconium phosphate intercalated with octadecyltrimethylammonium bromide (STAB-ZrP) as a thickener by thickening five types of base oils. The thickening ability and fluidity behavior of STAB-ZrP gel were evaluated using rheological measurements. The tribological properties of STAB-ZrP gel were investigated using a reciprocating tribometer under temperatures of 25 °C and −15 °C. The rheological results showed that STAB-ZrP gel had grease-like characteristics. Naphthenic and alkyl naphthalene as the base oil can lead to the higher thickening ability. Naphthenic oil maintained the most colloidal stability at 25 °C and −15 °C. STAB-ZrP gel exhibited superior anti-wear and friction reduction, owing to the formation of a solid protective film on the contact interface. The layered structure and morphology of STAB-ZrP after thickening were confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). This research established the relationship of STAB-ZrP with base oils in terms of their performance. STAB-ZrP acts as both a thickener and a solid additive in the STAB-ZrP gel system. This study can serve a beneficial trial for future preparations of lubricating grease. [ABSTRACT FROM AUTHOR]

China has almost 400 Mhm2 of grasslands, 90% of which is considered degraded to varying degrees, on which 16 million herders depend for their livelihoods and many more indirectly, along the value-adding chain. Since 1950, average stocking rates across China have increased 4-fold. National policies have focused over recent decades on finding ways to rehabilitate the degraded grasslands, to sustain livestock production from them, and to improve the livelihoods of herder households, who are among the poorest people in China. A large collaborative program commenced in the early 2000s to help find solutions to the sustainable management of grasslands. This paper summarizes key findings of many research projects, identifies where knowledge is weak and argues that the successful rehabilitation of grasslands will also require policies that provide incentives and support for herders as they move from a focus on survival to a focus on production of higher quality products, for which consumers are increasingly willing to pay. A key focus is to emphasize the improvement of animal production per head. When this is done, it naturally leads to lower stocking rates, which in turn provides the opportunities for grasslands to recover. Across a range of experiments, farm demonstrations and analyses using models, in Inner Mongolia and Gansu, a consistent result has been that a 50% reduction in stocking rates, improves net household income and starts the process of grassland rehabilitation. Rather than focusing on stocking rates, better management of grasslands could be achieved by maintaining the grasslands above critical values for herbage mass, values that help optimize botanical composition, reduce soil erosion, optimize animal growth rates and aid ecosystem functions. Managing to critical values for herbage mass is likely to be more effective than efforts to calculate sustainable stocking rates. An early summer rest is valuable for aiding grassland rehabilitation and summer productivity, but a total grazing ban (typically for 5 years) may not achieve its aims as evidence shows it may take 10–15 years to achieve a better grassland state. Less-desirable plant species often increase in degraded grasslands that are rested and grazing can help manage those species. Surveys of herders indicate they have very mixed views on the benefits of total grazing bans that are unlikely to rehabilitate grasslands to an ideal botanical composition. The current objective is to work with grasslands that herders now have and optimize the existing composition. Grazing grasslands in winter results primarily in weight loss by animals and there is now evidence of how winter grazing reduces grassland growth in the next summer. It is better to keep animals in well-built sheds and feed them better, improved feeding through the cold months is required. In addition to the application of results from national programs designed to improve grasslands, it will be important to train herders as they move from survival to production, to foster the development of better markets for their livestock products, to devise better financial support for herder businesses and to revise land tenure arrangements so that herders can expand the area of land they graze on better terms than apply at present.

Vanadium‐based intercalation materials have attracted considerable attention for aqueous zinc‐ion batteries (ZIBs). However, the sluggish interlaminar diffusion of zinc ions due to the strong electrostatic interaction, severely restricts their practical application. Herein, oxygen vacancy‐enriched V2O5 structures (Zn0.125V2O5·0.95H2O nanoflowers, Ov‐ZVO) with expanded interlamellar space and excellent structural stability are prepared for superior ZIBs. In situ electron paramagnetic resonance (EPR) and X‐ray diffraction (XRD) characterization revealed that numerous oxygen vacancies are generated at a relatively low reaction temperature because of partially escaped lattice water. In situ spectroscopy and density functional theory (DFT) calculations unraveled that the existence of oxygen vacancies lowered Zn2+ diffusion barriers in Ov‐ZVO and weakened the interaction between Zn and O atoms, thus contributing to excellent electrochemical performance. The Zn||Ov‐ZVO battery displayed a remarkable capacity of 402 mAh g−1 at 0.1 A g−1 and impressive energy output of 193 Wh kg−1 at 2673 W kg−1. As a proof of concept, the Zn||Ov‐ZVO pouch cell can reach a high capacity of 350 mAh g−1 at 0.5 A g−1, demonstrating its enormous potential for practical application. This study provides fundamental insights into formation of oxygen‐vacant nanostructures and generated oxygen vacancies improving electrochemical performance, directing new pathways toward defect‐functionalized advanced materials. [ABSTRACT FROM AUTHOR]

V3O7·H2O (VO) is an attractive cathode material for high‐capacity aqueous Zn‐ion batteries (AZIBs), but it is limited by slow ion mobility and low working platform voltage. Here, a 1,3‐propane diamine (DP)‐intercalated VO with nanoribbon‐assembled thorn flower‐like structure is fabricated by a facile hydrothermal method, noted as VO‐DP. The study shows that the zinc ion diffusion coefficient in VO‐DP (3.1 × 10−8 cm−2 s−1) is five orders of magnitude higher than that of a pure VO counterpart. Auxiliary density functional theory simulation shows that the embedded energy of zinc ions in VO‐DP significantly decreases from 0.24 to −2.5 eV, thus leading to excellent diffusion kinetics and superior rate performance. Benefiting from these unique properties, AZIBs composed of VO‐DP cathodes exhibit high operating voltage (0.89 V), remarkable capacities of 473 mA h g−1 at 0.05 A g−1, excellent rate capability (144 mA h g−1 at 10 A g−1) and long‐term cycling performance (73% capacity retention over 15 000 cycles at 10 A g−1). [ABSTRACT FROM AUTHOR]

Aiming at the problem of pulverized migration and plugging propped fractures during coal seam fracturing, we experimentally studied the pressure changes and pulverized coal blocking characteristics with deionized water and solutions of three surfactants including 1227 (C21H38ClN), SDS (C12H25SO4Na) and TX-100 (C34H62O11). A device capable of visualizing propped fractures was established, and simulation experiments were conducted with solutions of different surfactants at different injection flow rates. The obtained images were binarized and analyzed to quantify the pulverized coal blockage degrees of facture under different conditions. The experimental results show that: (1) The higher the injection flow rate, the higher the inlet pressure. (2) All three surfactants can lower the injection pressure, as compared with water alone. SDS decreases the injection pressure more obviously at low injection flow rates, and the other two perform better at high injection flow rates. (3) Similar to their effects on inlet pressure, the ratio of pulverized coal in SDS solution is lower at low injection flow rates, while TX-100 and 1227 solutions show lower ratios of pulverized coal at high injection flow rates. Our work has provided a theoretical support for coal blockage removal and pressure reduction in propped fractures during coal seam fracturing to improve coal seam permeability and further improves the dust prevention effect of coal seam water injection. [ABSTRACT FROM AUTHOR]