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There are many surface coal mines located in Inner Mongolia, which has dry and scarce topsoil, and the selection of topsoil alternatives is key to coal-mined land reclamation. This study used the l...

Development of a simple and label-free colorimetric sensing assay for dopamine is urgent, because of the important roles dopamine plays in many physiological processes. Herein, a label-free colorimetric method for determination of dopamine has been proposed based on the enhancement of the peroxidase-like activity of bare gold nanoparticles (AuNPs). The assay is based on specific interactions between protonated dopamine and gold atoms through the catechol group, which induces aggregation of AuNPs and significantly enhances their peroxidase-like activity. The catalytic activity is evaluated by chromogenic reaction of 3,3',5,5'-tetramethylbenzidine with H2O2. The mechanism for enhancement of catalytic activity is discussed. The detection limit of dopamine was 25 nM by virtue of UV-Vis spectroscopy, and 0.21 μM by naked eye. The whole detection procedure can be completed in 15 min. The proposed sensor is simple, fast, cost-effective and sensitive. These advantages make this sensor a powerful tool for the determination of dopamine in water samples.

To solve topsoil shortages caused by the thinner topsoil layer resulting from open-pit land reclamation in northwestern Chinese grassland areas, the overlying rock and soil layer of an open-pit coal mine in Inner Mongolia was used as a matrix, and different additives were incorporated to improve topsoil alternatives for dump reclamation. The physical and chemical properties and nutrient composition of the undisturbed matrix and the weathering substances in layers II and III of the topsoil were compared and analyzed, with local topsoil as the control. The results showed that the III layer of the matrix after weathering had higher nutrient content, pH of 7.83, EC of 83 μS/m, and as such was more suitable as a substitute for topsoil. Given the limitations of overlying strata, such as excessive viscosity, an imbalanced nutrient content and a lack of soil microorganisms, additives composed of vermiculite, peat, livestock manure, nitrohumic acid and microbial agents in different proportions were incorporated. Field experiments showed that the optimal formula of substitute material was a ratio of m (subclay):m (peat) = 20:1 and an applied microbial agent concentration of 0.15 kg/m2. Compared to the original topsoil, the substitute material had a higher moisture content (32% for substitute and 20% for original topsoil), significantly higher phosphorus and potassium contents, and similar or greater numbers of microorganisms. The greatest increase in alfalfa plant height was 72%, the dry weight of the aboveground part increased by 26%.

Fe-MCM-41, one kind of high-ordered mesoporous materials catalysts, with molar ratio of Fe/Si = 0.01-0.1, was synthesized by hydrothermal method from coal-series kaolin. Fe-MCM-41 catalysts were characterized by Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, N2 adsorption-desorption, x-ray photoelectron spectroscopy, and UV-vis spectroscopy. The results clearly indicated that: (1) all the samples exhibited typical hexagonal arrangement of mesoporous structure; (2) the incorporation of tiny amount of Fe3+ onto the surface and pore channel of MCM-41 mesoporous materials could efficiently promote the deNO x activity of these catalysts. Moreover, the Fe-MCM-41 mesoporous materials were evaluated in the selective catalytic reduction of NO with NH3. The results showed that Fe-MCM-41 catalyst with Fe/Si = 0.05 showed the highest catalytic activity at 350 °C, a gas hourly space velocity of 5000 h−1, n(NH3)/n(NO) = 1.1, and O2% = 2.5%.

Skilled human operators can adjust various conditions of manufacturing system and deal with unexpected troubles flexibly and appropriately. However, the operators can possibly fail the adjustment and dealing at times, because of fatigue, carelessness, bad physical condition, etc. The failure may cause some serious delay of the manufacturing processes and even physical danger to the operators. So, an intelligent system for avoiding the failure or warning its signs is desired to improve their working environment. To develop the system, a reliable recognition technique of operator's motion is indispensable. In this research, the recognition system of five kinds of motion in cylindrical grinding machine operation has been investigated by utilizing a small gyro/acceleration sensor and DP matching method. The similarity between the reference motion (standard pattern) and an input motion has been evaluated by the index of DP matching, or the pattern distance. The reference motions have been derived by averaging several typical motion data after time normalization. As the result, to recognize the objective five motions, first, the similarity indices by only angle data should be compared each other. Then, the similarity indices by only acceleration data should be compared, if necessary.

The mushroom compost which was produced from farm can be used to improving the quality of the reclamated soil. On the one hand, the question about environmental pollution made by the mushroom compost is solved, and on the other hand, it can improve the quality of the soil. In addition to the quality of the soil can be expressed by nutrient content. It also can be expressed by the number of microorganisms in the soil. At the same time, different fertilized time have different impact on soil quality. This article choice Zhoucheng City which was completed the reclamation in 2002 for study, research difference in timing of the application of mushroom caused the difference change in the number in soil bacteria, fungi and actinomycetes. which reflect the difference in timing of the application of changes in soil quality. With the depth of the soil increased, the number of micro-organisms is decreased. The area which were fertilized mushrooms compost in 2006 have the largest number of micro-organisms, un-fertilized area and the area which was fertilized in 2007 have smaller number of micro-organisms, and mushroom compost have different effect on the number of bacteria, fungi, and actinomycetes.