海洋中的凝集网与透明胞外聚合颗粒物

透明胞外聚合颗粒物(TEP)是海洋中大量存在的能被爱尔新蓝(alcian blue)染色的由酸性多糖组成的透明胶状颗粒物,主要来源于浮游植物,由于其透明的特性而被长期忽视。TEP同时具有胶体和颗粒物的特性。作为胶体,TEP为细菌提供了栖息场所与降解基质,同时TEP可以吸收痕量元素,以改变这些元素的生物地球化学过程。作为颗粒物,TEP可以聚集并沉降,由于其高的碳含量,会在很大程度上影响海洋的碳通量。由于TEP可以被中型浮游动物所摄食,所以TEP可以连接并缩短微食物环和经典食物链,在海洋生态系统中起很重要的作用。介绍了TEP的定义、测量方法、来源、形成、及其与浮游植物的关系和其生态功能。

PREPARATION AND PROPERTIES OF GEL POLYMER ELECTROLYTE BASED ON PVDF/ACRYLATE INTERPENETRATING POLYMER NETWORK FOR DYE-SENSITIZED SOLAR CELL

The gel polymer electrolytes（GPEs）based on poly（vinylidence fluoride）（PVDF）/acrylate interpenetrating polymer network（IPN）are prepared.The micro-phase separation type GPEs are characterized by Fourier transform infrared（FTIR）spectroscopy,scanning electron microscope（SEM）,respectively.Moreover,the conductivity and the voltage-current curves of the electrolytes are measured by electrochemical workstation.The higher porosity and electrolyte uptake are observed in the membranes prepared at lower crosslinker concentration.The suitable cross-linking acrylate monomer improves the porosity and the electrochemical behavior of GPE.A dye-sensitized solar cell（DSSC）employing PGE based on PVDF/poly（ethylene glycol dimethacrylate）（PEGDMA）IPN yields an open-circuit voltage of 0.674 V,short-circuit current of 8.476 mA·cm-2and the conversion efficiency of 2.710% under 100 mW·cm-2illumination.

Spatial Interaction and Network Structure Evolvement of Cities in Terms of China's Rail Passenger Flows

Cities separated in space are connected together by spatial interaction (SI) between them. But the studies focusing on the SI are relatively few in China mainly because of the scarcity of data. This paper deals with the SI in terms of rail passenger flows, which is an important aspect of the network structure of urban agglomeration. By using a data set consisting of rail O-D (origin-destination) passenger flows among nearly 200 cities, intercity rail distance O-D matrixes, and some other indices, it is found that the attenuating tendency of rail passenger is obvious. And by the analysis on dominant flows and spatial structure of flows, we find that passenger flows have a trend of polarizing to hubs while the linkages between hubs upgrade. However, the gravity model reveals an overall picture of convergence process over time which is not in our expectation of integration process in the framework of globalization and economic integration. Some driven factors for the re-organization process of the structure of urban agglomeration, such as technique advance, globalization, etc. are discussed further based on the results we obtained.

Research on Community Structure in Bus Transport Networks

We abstract the bus transport networks(BTNs)to two kinds of complex networks with space L and spaceP methods respectively.Using improved community detecting algorithm(PKM agglomerative algorithm),we analyzethe community property of two kinds of BTNs graphs.The results show that the BTNs graph described with space Lmethod have obvious community property,but the other kind of BTNs graph described with space P method have not.The reason is that the BTNs graph described with space P method have the intense overlapping community propertyand general community division algorithms can not identify this kind of community structure.To overcome this problem,we propose a novel community structure called N-depth community and present a corresponding community detectingalgorithm,which can detect overlapping community.Applying the novel community structure and detecting algorithmto a BTN evolution model described with space P,whose network property agrees well with real BTNs',we get obviouscommunity property.

How to Make Virtual Community More Active and Cohesive:From Brand and Perceived Protection Perspectives

With the increasing popularity of the Internet and mobile Internet, the Virtual Community （VC） is becoming an important medium for person-to-person communication. To realise the potential of the VC, it is neces- sary to cultivate within it good group cohesion and vitality. Using empirical and experimental research methods, this study explores the ef- fect of users＇ trust in the VC Platform （VCP） on group cohesion and vitality and how brand and perceived privacy security can affect us- ers＇ trust in the VC. The research results indi- cate that the brand of the VCP can directly af- fect users＇ trust in the VC, and can also influe- nce it indirectly through users＇ perceived pri- vacy protection and perceived security protec- tion. Further, this study also confu＇ms that the performance of the VC （group cohesion and vitality） is significantly affected by users＇ trust in the VC. The results of this study can provide theoretical guidance for internet companies to maintain and enhance the value of VCs.