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A B S T R A C TPrecursor was prepared from rice husk under different carbonization temperatures. Then, activated carbon (AC) was synthesized by NaOH activation. The specific surface area of carbon increased with temperature rise up to 600˚C, but decreased rapidly over 600˚C. So, the AC obtained at 600˚C possessed the outstanding surface area of 2,802 m 2 /g. And, its adsorption activity of nitrate was carried out at initial concentration of 50-400 mg/L. The results showed that the maximum adsorption capacity and removal percentage of NO À 3 were 70.2 mg/g and 70.6%, respectively. Besides, the experimental data were evaluated by Langmuir, Freundlich, and Redlich-Peterson isotherms. In kinetic studies, it was observed that the results were well explained by the pseudo second-order model. In addition, the Gibbs free energy change of À17.0 kJ/mol indicated that the adsorption process was spontaneous.

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In this paper, grinding experiments on the machining of SiCp/Al composites using SiC grinding wheel have been carried out. The effect of the grinding parameters on the grinding forces, surface morphology and surface roughness were evaluated. The results indicate that the grinding depth has more significant effect on the grinding force than that of feed speed, and there are many fracture or crushed SiC particles on the ground surface. Therefore, the SiC wheels can be used for rough grinding of SiCp/Al composites.

The Mesozoic–Cenozoic tectonic movement largely controls the northwest region of the Junggar Basin (NWJB), which is a significant area for the exploration of petroleum and sandstone‐type uranium deposits in China. This work collected six samples from this sedimentary basin and surrounding mountains to conduct apatite fission track (AFT) dating, and utilized the dating results for thermochronological modeling to reconstruct the uplift history of the NWJB and its response to hydrocarbon migration and uranium mineralization. The results indicate that a single continuous uplift event has occurred since the Early Cretaceous, showing spatiotemporal variation in the uplift and exhumation patterns throughout the NWJB. Uplift and exhumation initiated in the northwest and then proceeded to the southeast, suggesting that the fault system induced a post spread‐thrust nappe into the basin during the Late Yanshanian. Modeling results indicate that the NWJB mountains have undergone three distinct stages of rapid cooling: Early Cretaceous (ca. 140–115 Ma), Late Cretaceous (ca. 80–60 Ma), and Miocene–present (since ca. 20 Ma). These three stages regionally correspond to the Lhasa‐Eurasian collision during the Late Jurassic–Early Cretaceous (ca. 140–125 Ma), the Lhasa‐Gandise collision during the Late Cretaceous (ca. 80–70 Ma), and a remote response to the India‐Asian collision since ca. 55 Ma, respectively. These tectonic events also resulted in several regional unconformities between the J3/K1, K2/E, and E/N, and three large‐scale hydrocarbon injection events in the Piedmont Thrust Belt (PTB). Particularly, the hydrocarbon charge event during the Early Cretaceous resulted in the initial inundation and protection of paleo‐uranium ore bodies that were formed during the Middle–Late Jurassic. The uplift and denudation of the PTB was extremely slow from 40 Ma onward due to a slight influence from the Himalayan orogeny. However, the uplift of the PTB was faster after the Miocene, which led to re‐uplift and exposure at the surface during the Quaternary, resulting in its oxidation and the formation of small uranium ore bodies.

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