The influence of the functional groups in MIL-101(Cr)-X metal−organic frameworks (MOFs) with X = H, NH 2 , and NO 2 on the adsorption properties of N/S-heteroaromatic compounds from model fuels was investigated. Benzothiophene (BT), dibenzothiophene (DBT), quinoline, and indole were selected as representative organosulfur and organonitrogen contaminants in liquid fuels. Their adsorption on four MIL-101 materials from model fuels was evaluated in a batch adsorption system. Introducing amino or nitro group into MIL-101(Cr) leads to decreased adsorption capacities of BT and DBT from isooctane, especially the bulkier nitro group. The adsorption capacities of indole and quinoline from isooctane also decrease when introducing nitro group. However, the adsorption capacities of quinoline and indole on amino-MIL-101(Cr) increase by about 25% and 10% even through the porosity is 30% lower than that of the parent. The improved adsorption capacities of amino-MIL-101(Cr) for quinoline and indole are attributed to hydrogen bonding between the NH 2 group and organonitrogen compounds. MIL-101(Cr)-NH 2 can retain most of its capacity for quinoline in the presence of substantial amounts of aromatics, making it a potential adsorbent for the deep denitrogenation of fuels.

The magnetic susceptibility of loess from the Ily Basin, northwestern China shows maximum values in S0 paleosols but minimum values in other paleosols, the mechanism of which has been well debated. In this work, systematic magnetic measurements were made on a representative section from Neleke county. The results show that the loess horizons (L1, L2 and L3) have multi-domain magnetite grains of aeolian origin, S0 is characterized by production of pedogenetic ultrafine-grained ferrimagnetic minerals, and the other paleosols (S1, S2, and S3) are characterized by the formation of nonferrimagnetic minerals associated with waterlogging. The correlation between the low concentration of ferrimagnets, high paramagnetic content, high magnetic coercivity remanence, fine ferrimagnetic grain size and intensified pedogenesis suggest two competing processes of pedogenetic enhancement and pedogenetic depletion in the lower paleosols. Pedogenetic depletion dominates and is responsible for the low susceptibility. Changes in magnetic grain size distribution occur during pedogenetic depletion. The susceptibility variations are of multiple origins in the loess of the Ily Basin. Pedogenetic enhancement, pedogenetic depletion, and allochthonous input of magnetic minerals should all be taken into account to explain the variations of magnetic parameters. magnetic susceptibility, magnetic depletion and enhancement, loess, Ily Basin, environmental magnetism Citation:Chen Q, Liu X M, Heller F, et al. Susceptibility variations of multiple origins of loess from the Ily Basin (NW China). Chin Sci Bull, 2012Bull, , 57: 18441855, doi: 10.1007 Low field magnetic susceptibility of loess records are widely used in paleoenvironmental research. The magnetic properties in loess records can be attributed to both original aeolian input and post-depositional pedogenesis [1]. Post-depositional pedogenesis can result in susceptibility enhancement or depletion and the interaction of these processes are site-specific [1,2]. Different models have been put forward to explain these susceptibility variations of different patterns. The pedogenetic enhancement model suggests that ultrafine ferrimagnetic minerals were formed during the pedogenesis process. This accounts for the high susceptibility in paleosols and low susceptibility in loess, and can be used to explain loess deposits on the Chinese Loess Plateau [3][4][5][6][7][8]. The wind vigor model displays low susceptibility in paleosols and high susceptibility in loess. It argues that for loess from Alaska and Siberia, allochthonous input plays an important role in magnetic concentration and intensified wind vigor is responsible for increases in susceptibility [9][10][11][12][13][14][15]. However, pedogenesis influences not only the magnetic concentration but also the magnetic mineralogy and contributes at least partly to susceptibility variations in loess from . A negative relationship between susceptibility and the degree of pedogenesis was found in the Ily Basin, northwestern China [21][22][23][24][25...

Concentrated animal feeding operations (CAFOs) such as dairy farms are a source of odorous compound emissions. In this study, by identifying relevant odour sources within a 300-head dairy farm and quantifying their emissions, we determined the separation distances to avoid odour annoyance around the dairy farm with two empirical models (Austrian and German Verein Deutscher Ingenieure (VDI) model) and a dispersion model (AERMOD). Besides, this study ponders on the selection of an appropriate meteorological station that best represents the area surrounding the farm. Results show that the maximum separation distances of an exceedance probability of P = 15% determined by the two empirical and the dispersion models are 524 m, 440 m and 655 m, while the minimum values are 202 m, 135 m, and 149 m, respectively. The NE–SW stretching separation distances match well with the wind rose. The mean ratios of separation distances determined by the two empirical models to that of the dispersion model are 1.23 and 0.95. Moreover, statistics of the separation distances indicate good accordance between the empirical models and the dispersion model.

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