Simultaneous measurements of the vertical magnetic field (VMF), three-dimensional electric field, ambient temperature, ambient relative humidity, particle mass concentration, and three-dimensional velocity are conducted during dust, haze, rain, snow, and thunderstorms. The hourly VMF variation (the rate of VMF increment and time increment with a 1-h time interval) is used to evaluate the disturbance level of the atmospheric magnetic field during the abovementioned weather conditions. There is no significant difference in the hourly VMF variations between hazy days and fair weather. However, the hourly VMF variations on dusty, rainy, snowy, and thunderstorm days differ from those in fair weather, implying that these weather conditions significantly affect the atmospheric magnetic field. On hazy days, although the haze particles are charged, the VMF does not change compared with in fair weather, which suggests that the horizontal electric field generated by haze particles is an irrotational field. On dusty and snowy days, the heterogeneity of the charge distribution forms a rotational horizontal electric field, which can induce the VMF to disturb the atmospheric magnetic field. During rain and thunderstorms, the hourly variation in the VMF is larger than in dust and snow, which can be attributed to the rotational horizontal electric field generated by raindrops and clouds. In addition, the hourly variation in the VMF in thunderstorms is one order of magnitude larger than that during days without thunderstorms, indicating that the VMF induced by the cumulonimbus cloud electric field is more significant than that in other weather conditions.
The spatial and sectoral distribution of Foreign Direct Investment (FDI) in China has changed dramatically in the past two decades. FDI was largely concentrated in the Pearl River Delta (PRD) and other Southern Coastal provinces in early stages and shifted to the Yangtze River Delta (YRD) and the Bohai Economic Rim (BER) sequentially in later stages. It created unique and dynamic paths of the spatial evolution of FDI in China. Although many provinces have received relatively more FDI since the late 2000s, Guangdong and Jiangsu are still the two major recipients of FDI in China, demonstrating and over-arching polarization process. Furthermore, most FDI in China has been in the manufacturing sector, making China well-known as the “World Factory of Manufacturing”. This paper analyses the most recent trends, characteristics and patterns of FDI in China. It portrays the factors that determined the investment location and the dynamic pathways of different kinds of FDI. This paper also foresees the possible changes in spatial and sectoral distribution of FDI in the near future and provides policy suggestions for both China and other developing countries in seeking new FDI inflows and transforming their industrial structures and economies in this particular phase of globalization. 相似文献
This special column was the outcomes of the Public Forum on China’s Spatial Strategic Planning and Development in the National 12th Five-year Plan held at the University of Hong Kong (HKU) in April 2011.The Public Forum was jointly organized by the International 相似文献
The Bohai Sea is a semi-enclosed inland sea with case-2 waters near the coast. A comprehensive set of optical data was collected during three cruises in June, August, and September 2005 in the Bohai Sea. The vertical profile measurements, such as chlorophyll concentration, water turbidity, downwelling irradiance, and diffuse attenuation coefficient, showed that the Bohai Sea was vertically stratified with a relative clear upper layer superimposed on a turbid lower layer. The upper layer was found to correspond to the euphotic zone and the deep chlorophyll maximum (DCM) occurs at the base of this layer. By tuning a semi-analytical model (24 and 25) for the Bohai Sea, we developed a method to derive water inherent optical properties and the depth of DCM from above-surface measurements. Assuming a ‘fake’ bottom in the stratified water, this new method retrieves the ‘fake’ bottom depth, which is highly correlated with the DCM depth. The average relative error between derived and measured values is 33.9% for phytoplankton absorption at 440 nm, 25.6% for colored detrital matter (detritus plus gelbstoff) absorption at 440 nm, and 24.2% for the DCM depth. This modified method can retrieve water inherent optical properties and monitor the depth of DCM in the Bohai Sea, and the method is also applicable to other stratified waters. 相似文献