Nanjing University

About: Nanjing University is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 85961 authors who have published 105504 publications receiving 2289036 citations. The organization is also known as: NJU & Nanking University.

Toxicological effects of TiO2 and ZnO nanoparticles in soil on earthworm Eisenia fetida.

Abstract: Nanoparticles (NPs) of TiO2 and ZnO are receiving increasing attention due to their widespread applications. To evaluate their toxicities to the earthworm Eisenia fetida (Savigny, 1826) in soil, artificial soil systems containing distilled water, 0.1, 0.5, 1.0 or 5.0 g kg−1 of NPs were prepared and earthworms were exposed for 7 days. Contents of Zn and Ti in earthworm, activities of antioxidant enzymes, DNA damage to earthworm, activity of cellulase and damage to mitochondria of gut cells were investigated after acute toxicity test. The results from response of the antioxidant system combined with DNA damage endpoint (comet assay) indicated that TiO2 and ZnO NPs could induce significant damage to earthworms when doses were greater than 1.0 g kg−1. We found that Ti and Zn, especially Zn, were bioaccumulated, and that mitochondria were damaged at the highest dose in soil (5.0 g kg−1). The activity of cellulase was significantly inhibited when organisms were exposed to 5.0 g kg−1 of ZnO NPs. Our study demonstrates that both TiO2 and ZnO NPs exert harmful effects to E. fetida when their levels are higher than 1.0 g kg−1 in soil and that toxicity of ZnO NPs was higher than TiO2.

Electrocatalytic Hydrogen Evolution Reaction on Edges of a Few Layer Molybdenum Disulfide Nanodots.

Abstract: The design and development of inexpensive highly efficient electrocatalysts for hydrogen production underpins several emerging clean-energy technologies. In this work, for the first time, molybdenum disulfide (MoS2) nanodots have been synthesized by ionic liquid assisted grinding exfoliation of bulk platelets and isolated by sequential centrifugation. The nanodots have a thickness of up to 7 layers (∼4 nm) and an average lateral size smaller than 20 nm. Detailed structural characterization established that the nanodots retained the crystalline quality and low oxidation states of the bulk material. The small lateral size and reduced number of layers provided these nanodots with an easier path for the electron transport and plentiful active sites for the catalysis of hydrogen evolution reaction (HER) in acidic electrolyte. The MoS2 nanodots exhibited good durability and a Tafel slope of 61 mV dec–1 with an estimated onset potential of −0.09 V vs RHE, which are considered among the best values achieved for 2...

Carboniferous granitic plutons from the northern margin of the North China block: implications for a late Palaeozoic active continental margin

Abstract: We report four late Palaeozoic zircon sensitive high-resolution ion microprobe (SHRIMP) U–Pb ages for granitic plutons from the Inner Mongolia Palaeo-uplift on the northern margin of the North China block. These cast a new light on the poorly understood tectonic history of the northern margin of the North China block and the Central Asian Orogenic Belt during the late Palaeozoic. The plutons have for a long time been considered to belong to the early Precambrian basement of the North China block. Our new SHRIMP U–Pb zircon dating of four plutons at Longhua, Daguangding, Boluonuo and Hushiha has yielded intrusive ages of 311 ± 2 Ma, 324 ± 6 Ma, 302 ± 4 Ma and 310 ± 5 Ma, respectively. Geochemical data suggest that these granitoids have a calc-alkaline, subduction-related I-type signature, indicating the existence of an Andean-style continental arc along the northern margin of the North China block during the late Palaeozoic. Our results also indicate that the Palaeo-Asian Ocean still existed during latest Carboniferous–earliest Permian time, and that the final collision between the southern Mongolia composite terranes and the North China block occurred later than c . 290 Ma. We suggest that the northern margin of the North China block was an active continental margin and the Inner Mongolia Palaeo-uplift is a deeply exhumed mid-crustal ‘root’ of a late Palaeozoic Andean-style continental arc.

Carbon emissions from land-use change and management in China between 1990 and 2010.

Abstract: China has experienced enormous changes in land use in recent decades, which are largely driven by its unparalleled economic development. We analyze changes in vegetation and soil carbon storage between 1990 and 2010 resulting from combinations of land-use category conversion and management. Results demonstrate a major decline in grasslands (−6.85%; 20.83 × 106 ha) and large increases in urban areas (+43.73%; 6.87 × 106 ha), farmlands (+0.84%; 1.48 × 106 ha), and forests (+0.67%; 1.52 × 106 ha). The total soil organic carbon pool has been reduced by approximately 11.5 Tg of carbon (TgC) year−1, whereas 13.2 TgC year−1 has accumulated in the biomass carbon pool because of land-use category change. Large carbon losses (approximately 101.8 TgC year−1) have resulted from land management failures, including forest fires and insect pests. Overall land-use change and land management have contributed about 1.45 Pg of carbon to the total carbon released from 1990 to 2010. Our results highlight the importance of improving land-use management, especially in view of the recently proposed expansion of urban areas in China.