Longjun Zhang

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The water containing high fluoride ions could do harm to human and environment. In this work, the applicability of neodymium-modified chitosan as adsorbents for the removal of excess fluoride ions from water was studied. The effect of various physico-chemical parameters such as temperature (283-323 K), pH (5-9), adsorbent dose (0.2-2.0 g L(-1)), particle(More)
We investigated the partial pressure of carbon dioxide (pCO(2)) in Jiaozhou Bay (JZB), which is surrounded by the economically developed city of Qingdao, during two cruises undertaken in November, 2007 (autumn) and February, 2008 (winter). Results indicated that sea surface pCO(2) in autumn varied between 315 and 720 μatm, with an average level of 418 μatm.(More)
The sensitivity of frequency response on different frequency spectrums is analyzed by sensitivity analysis. And more analysis is simulated by computer. Then the relation of transformer parameters' changing when the winding deformed are figured out by analysis of capacitance and inductance. Furthermore, dependent on the statistics of winding deformation, the(More)
Jiaozhou Bay has recently suffered from serious problems with pollution and eutrophication. Thus, land-based pollutant load must be reduced through a national control program. In this study, we developed a 3D water quality model to determine the environmental capacity of nitrogen and phosphorus in Jiaozhou Bay. A 3D hydrodynamic model (the estuarine,(More)
Based on the analysis on the security mechanism of wireless local network (WLAN), we found that due to the initialization vector (IV) which is published by Wired Equivalent Privacy (WEP) protocol without encrypting, there are many serious secure leaks in its application. In this paper, We propose an efficient signcryption scheme to the IV based on the(More)
A novel omni-directional Ultra-Wide Band (UWB) biconical antenna with band-notched is described. Firstly, the biconical antenna in the shape of two kinds of bicone placed above a flat ground plane is designed. The antenna operates from 2.4–20 GHz with low Voltage Standing Wave Ratio (VSWR<2), excluding a band-notched frequency at(More)
We mined the literature for proteomics data to examine the occurrence and metastasis of prostate cancer (PCa) through a bioinformatics analysis. We divided the differentially expressed proteins (DEPs) into two groups: the group consisting of PCa and benign tissues (P&b) and the group presenting both high and low PCa metastatic tendencies (H&L). In the P&b(More)
Today, the cloud computing has been an important platform for various resources and sharing. But at present, many cloud computing platforms have not used the service-oriented system architecture, which could bring about more flexibility, higher extendibility and reusability. The cloud computing has always been an important computing platform for sharing(More)
The secure problem is one of the key problems of E-commerce and the security of E-commerce is becoming a bottleneck for its further applications. At present, many organizations and manufacturers are trying to solve this problem. However, owing to the serious secure leak in Internet, it is impossible to completely solve the problem by packs. Based on the(More)