This paper takes mobile phone as an example to analyze the innovation of WEEE takeback system in Guangdong. With interviews on various enterprises at different stage along the recycling chain, three models of waste mobile phone collection were identified. Spatial analysis was conducted on the cost of reverse logistics under each model for waste mobile phone collection in Guangdong. The results show that Guangdong will have 16.62 million wasted mobile phones in 2020. The cost of collection for environmental recycling by the municipal waste transportation system is much cheaper than the cost of collection directly by producers. While considering the net profit of internet collection for second-hand sales, the internet collection is more profitable. In conclusion, it is suggested that the producer could integrate the different collection system into their reverse logistic system under the principle of EPR, using the profits from second market sales through internet to cover the cost of environmental recycling.

Shrublands in the Beijing-Tianjin-Hebei region were selected to unveil relationships between the area percentage of shrubland and the slope angle. Gridded data of vegetation and slope angle were correlated for the whole region as well as different climatic regimes with piecewise regression analysis. The results show that there is a tipping point on the fitted curve between percentage of shrubs and slope angle, instead of a monotonous linear fit. On gentle slopes, percentage of shrubs increases with the increase of slope angle, which might be caused by the decrease of human cultivation. On steep slopes, there are divergent patterns, percentage of shrublands except that dominated by Vitex negundo var. heterophylla and Zizyphus jujuba var. spinosa decreases with the increase of slope angle, which might be caused by resource limitation. Percentage of this shrubland type does not show trend of decline with slope angle increase, which might be caused by its distribution on low elevations and its adaptation to varied habitats. In addition, the tipping point mostly fixes around 15 degree of slope angle when the region is taken as a whole; it changes under different climatic regimes.

In order to enhance the understanding of the late Paleozoic tectonic settings of northern margin of the north China craton (NNCC) and closure time of the Paleo-Asian Ocean, the zircon U-Pb age, geochemistry and zircon Hf isotope of the Xiaojinggou granite are conducted by LA-MC-ICP-MS, ICP-AES and ICP-MS. The zircon U-Pb dating results indicate that the Xiaojinggou pluton was intruded at Permian (275±1 Ma, MSWD=0.93). All the granite have high contents of SiO₂ (70.72%?to?72.64%), K₂O (4.19% to 4.23%) with moderate A/CNK values (averaged at 1.1), suggesting that Xiaojinggou pluton is slightly peraluminous and belongs to the high-K calc-alkaline series. The concentrations of rare earth elements (ΣREE) varies in the range of 87.67 to 101.51 μg/g. The Xiaojinggou pluton is characterized by enriched LREE patterns with slightly negative Eu anomalies. It is enriched in large ion lithophile elements (LILE, e.g. Rb, Ba, K, Sr), but depleted in high field strength elements (HFSEs, e.g. Nb, Ta, Y, Yb, Lu), which suggest this plutou may be derived from partial melting of the lower crust. Zircon ε_Hf(t) value varies from -9.56 to -5.00 and T_DM2 varies in the range of 1.91 to 1.61 Ga. All these characters indicates that the Xiaojinggou pluton is probably generated by partial melting of Lower Proterozoic crust of the NNCC, accompanied by the possible assimilation of mantle-derived magmas. In view of the evolution of the Permian granitic magmatism in the NNCC, middle Permian Xiaojinggou pluton formes in the transition period from subduction to collision/post-collision, and the Paleo-Asian Ocean should close before late Permian.

Based on the second national soil survey data，the pools and spatial patterns of soil phosphorus density in China was investigated.The relationships between soil phosphorus density and environmental factors were also presented. The results indicate that the total national soil total and available phosphorus pools at actual depth are 5.1Pg and 3.0Tg, respectively. The average total phosphorus density and available density are 0.60kg?m² and 3.4g?m², respectively. Total soil phosphorus density, which negatively correlates with mean annual temperature and precipitation, showes increased tendency both from humid to semi-arid/arid zones and from tropical to frigid/temperate zones. Among different soil geochemical types, available phosphorus density of Siallitic soils significantly higher than those of Gypsum-bearing and Calcareous soils and Ferrallitic and Allitic soils. In conclusion, climate and soil geochemical types are important factors controlling soil phosphorus density in China.

Conjugate fractures have an acute angle to σ₁, while conjugate deformation zones with an obtuse angle to it. The acute angle can be explained with the Mohr-Coulomb criterion, whereas the obtuse one can be elucidated with the Maximum Effective Moment Criterion (MEMC), which is recently proposed. The MEMC is mathematically expressed as M_eff=0.5(σ₁-σ₃)Lsin2αsinα, where α₁-α₃ represents the yield strength of the related rock, L is a unit length and α is the angle between α₁ and deformation bands. This criterion demonstrates that the maximum value appears at angles of ±54.7° to α₁ and there is little difference in the moment in the range of 55°±10°. The range covers all the observations available from nature and experiments. In practice, it can be used for elucidate many geological structures such as kink-bands and extensional crenulation cleavages, yield zones in evaporates, low-angle normal faults and high-angle reverse faults, lozenge ductile shear zones in basement terranes, some crocodile structures in seismic profiles and detachment folds in foreland basins. It may be used to determine the stress state when the related deformation features formed and provides a new approach to determine the W_k of the related ductile shear zone. It can also be extended to explain the relationship between orogenic and late-orogenic extension events, and uplift and exhumation of ultrahigh pressure rocks that experienced deep subduction.

Studies were made on the enhancement of expression of human pro-Urokinase (Pro-UK) cDNA in Eschevichia coli. By means of PCR, the signal peptide DNA sequence was deleted. For study of the limited factors in expression of pro-Urokinase, the pro-UK gene was divided into three fragments, and they were expressed in E.coli BL21(DE3), The expression of middle fragment is very low, because there are several rare codon AGG(Arg) in it. Using a new bacteria E.coli BL21-Codo nPlus^TM-RIL to introduce dnaY gene coding tRNA_agg/aga(Arg) to recognize the rare codon AGG, the expression level of the middle fragment was enhanced to 10%～20% of total cell protein and the expression of the intact pro-UK was enhanced to 5% by more than 10 folds.