Spin Injection from Ferromagnetic Semiconductor CoZnO into ZnO

2X (FeNi/CoZnO )/ZnO/(CoZnO/Co ) X2 纺纱注射设备被劈啪作响和 photo-lithography.In 准备设备，二合成的磁性的层 2X (FeNi/CoZnO ) 并且(CoZnO/Co ) 有不同 coercivities 的 X2 被用来制作基于 ZnO 的半导体旋转阀门。因为 CoZnO 铁磁性的半导体层直接摸了 ZnO 空间层，从进 ZnO 的 CoZnO 的重要旋转注射被测量纺纱注射设备的磁致电阻观察。磁致电阻在房间温度在 90 K 与增加温度线性地归结，从 1.12% 为 0.35% 。

Land Use Change and Driving Forces in Guangzhou City during 1996- 2012

Based on the statistical data of land use change,from the perspective of sustainable use,we use literature inquiry,statistical analysis,GIS spatial analysis and dynamic degree model of land use,to analyze the land use change characteristics,land use amount and spatial distribution characteristics in Guangzhou City during 1996- 2012,and further elaborate the driving forces of land use change to get the basic law of land use change in Guangzhou City. The results show that the construction land was rapidly expanded,causing a significant reduction in arable land( from 129286 ha in 1996 to 84567 ha in 2012); in construction land,the land for residential,industrial and mining use and transportation land dramatically increased,and the single dynamic degree of transportation land was close to 7. 1%. In comparison with other developed cities,it is found that economic factors and policy factors are important factors affecting land use change in Guangzhou City,and the growth rate of economic density of land was high in Tianhe District and Yuexiu District. From the perspective of sustainable use,the future land use in Guangzhou City needs to better coordinate the relationship between various types of land,between socio-economic development and coordinated land use development,between environmental protection and land development and utilization. Through a series of land consolidation activities,it is necessary to strengthen the protection of farmland,improve the intensive and economical use of construction land,improve the ecological environment,and coordinate development of urban and rural areas,to ultimately achieve sustainable land use in Guangzhou City.

Current spin polarization and spin injection efficiency in ZnO-based ferromagnetic semiconductor junctions

[FeNi(3 nm)/Zn1-xCoxO(3 nm)]2/ZnO(d nm)/[Zn1-xCoxO(3 nm)/Co(3 nm)]2(d=3 and 10) semiconductor junctions were prepared by magnetron sputtering system and photolithography.The spin valve effect was observed in these junctions because the utility of the ferromagnetic composite layers acted as soft and hard magnetic layers.The electrical detection was performed by measuring the magnetoresistance of these junctions to investigate the current spin polarization αsc in the ZnO layer and the spin injection efficiency η of spin-polarized electrons.αsc was reduced from 11.7%(and 10.5%) at 90 K to 7.31%(and 5.93%) at room temperature for d=3(and d=10).And η was reduced from 39.5%(and 35.5%) at 90 K to 24.7%(and 20.0%) at room temperature for d=3(and d=10).

Distribution of chlorpyrifos in rice paddy environment and its potential dietary risk

Chlorpyrifos is one of the most extensively used insecticides in China. The distribution and residues of chlorpyrifos in a paddy environment were characterized under field and laboratory conditions. The half-lives of chlorpyrifos in the two conditions were 0.9–3.8 days(field) and 2.8–10.3 days(laboratory), respectively. The initial distribution of chlorpyrifos followed the increasing order of water < straw < soil, and soil was characterized as the major absorber. The ultimate residues in rice grain were below the maximum residue limit(MRL) with a harvest interval of 14 days. The chronic exposure for chlorpyrifos was rather low compared to the acceptable daily intake(ADI = 0.01 mg/kg bw) due to rice consumption. The chronic exposure risk from chlorpyrifos in rice grain was 5.90% and 1.30% ADI from field and laboratory results respectively. Concerning the acute dietary exposure,intake estimated for the highest chlorpyrifos level did not exceed the acute reference dose(ARf D = 0.1 mg/kg bw). The estimated short-term intakes(ESTIs) were 0.78% and 0.25% of the ARf D for chlorpyrifos. The results showed that the use of chlorpyrifos in rice paddies was fairly safe for consumption of rice grain by consumers.

Environmental behaviors of phoxim with two formulations in bamboo forest under soil surface mulching

Phoxim(emulsifiable concentrate(EC) and granules(G)) has been widely used in bamboo forests. The persistence and magnitude of phoxim residues in the crop and soil must be investigated to ensure human and environmental safety. The environmental behaviors of the two formulations were investigated in a bamboo forest under soil surface mulching conditions(CP) and non-covered cultivation conditions(NCP). The half-lives of phoxim in soil under the two conditions in soil were 4.1–6.2 days(EC) and 31.5–49.5 days(G),respectively. Phoxim in EC could be leached from the topsoil into the subsoil. A minimized leaching effect was observed for G under NCP. Inversely, an enhanced leaching effect was observed for G under CP. The G formulation resulted in more parent compound(in bamboo shoots) and metabolite(in soil) residues of phoxim than in the case of EC, especially under CP conditions. In addition, the intensity and duration of the formulation effect on soil p H adjustment from G were more obvious than that from EC. Results showed that the environmental behaviors(distribution, degradation, residue) of phoxim in the bamboo forest were significantly influenced by the type of formulation. The prolongation effect from phoxim G might cause persistence and long-term environmental risk. However,bamboo shoot consumption could be considered relatively safe after applying the recommended dose of the two phoxim formulations.

The phytochemical components of walnuts and their application for geographical origin based on chemical markers

Place of origin has an important influence on walnut quality and commercial value,which results in the requirement of rapid geographical traceability method.Thus,a method for geographical origin identification of walnuts on the basis of nutritional quality of walnuts from China was conducted.The concentrations of 43 phytochemical components were analyzed in walnut samples from five different walnut-producing regions of China.Based on 14 chemical markers selected by the Random Forest method from these phytochemical components,a new discriminant model for geographical origin was built,with the corresponding correct classification rate of 99.3%.In addition,the quantitative quality differences of walnuts from five regions were analyzed,with values of 0.17–1.43.Moreover,the top three chemical markers for the geographical origin discriminant analysis were Mo,V,and stearic acid,with contribution rates of 26.8%,18.9%,and 10.9%,respectively.This study provides a potentially viable method for application in food authentication.