Qingdao lies in the south of Shandong Peninsula, on the coast of the Yellow Sea. As a coastal and hilly city, Qingdaohas topographic features consisting of twisted coastlines dotted with capes and bays. The beginning of the 20th century witnessed the construction of western-style streets and buildings in Qingdao when it was occupied by Germany. Liyuan is the name of the residential buildings for Chinese labors during the German occupation. Liyuan retain the spatial composition of Chinese quadrangles (Siheyuan), and at the same time feature western technology. Therefore they have both Chinese and western flavors. In addition, they are the earliest urban residential complexes in China. The space system of Liyuan blocks has played an important role in the lifestyle and social network of the local residents. Liyuans have been home to Qingdao people from generation to generation, which makes it a spiritual symbol. Owing to its history and characteristics, Liyuan architecture has been designated as one of the historical and cultural protected areas in Qingdao, and has contributed to the formation of a distinctive geographical landscape. Since the 1980s, urban renewal and redevelopment in Qingdao have greatly impacted upon the protection of Liyuans, which has aroused concern from various communities.This research on Liyuans shows the geographic location of all the Liyuan blocks, classifies them in terms of courtyard composition and architectural features, and analyzes the relationship between their spatial composition and the residents’ life-style.
This paper reports a kind of banana peel carbon (BPC) containing -OH, -NH2 functional groups which prepared through controlling carbonization temperature and its application on the selective adsorption of gold from waste printed circuit boards (PCBs). The adsorption of BPC for Au(III) reached equilibrium in 30 min and the adsorption of Au(III) was favorable at pH 2.5. Meanwhile, the adsorption isotherm showed the maximum adsorption capacity of 801.7 mg/g for Au(III). The results displayed that BPC had a strong selectivity for Au(III) and a negligible affinity to base metal ions, such as Cu(II), Ni(II), Fe(III) and Pb(II). The BPC adsorbent, which absorbed gold, can be recovered completely by HCl-thiourea solution.
A hyperparasitic system with prolonged diapause for host is investigated. It is assumed that host prolonged diapause occur at larval stage, and parasitoid attack is limited to egg stage before the initiation of host diapause. Such behavior has been reported for many ichneumons. Hyperparasite only attacks the parasitoids that parasitize the hosts. Hyperparasitic system is often used in biological control. The existence and stability of nonnegative fixed points are explored. Numerical simulations are carried out to explore the global dynamics of the system, which demonstrate appropriate prolonged diapause rate and appropriate intrinsic growth rate can stabilize the system. The reasons are explained according to the ecological perspective. Furthermore, many other complexities which include quasi-periodicity, period-doubling bifurcations leading to chaos, chaotic attractor, intermittent and supertransients are observed.