Volume 3 Issue 12
Authors: Ting-Li Lu; Yu-Fan Ma; Wen Zhao; Tao Chen
Abstract: Hydrophobic bisphosphate amidated derivatives (1a-1d) anchored long alkyl chains were designed and obtained through the reaction of –NH2 in BPs and –COOH in fat acid under anhydrous condition. The structure of derivatives was investigated by fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and mass spectrometer (MS) and the results showed that the final products were amidated compounds with the long alkyl anchored in alendroante’s lateral chain R2. The physicochemical parameters, such as the solubility and partition coefficient in n-octanol/water, were also determined through calculated by performing reversed phase high performance liquid chromatography (RP-HPLC). Compared with alendronate, the derivatives had a very low aqueous solubility and had little or even no measurable solubility values in PBS. While it had different solubility in organic solvents with different polarities. The partition coefficient Po/w of derivatives in n-octacol/water mixture was calculated and the results showed that the derivatives had higher Po/w data than that of alendronate and the longer the alkyl chain was introduced, the higher the partition coefficient was. All of the above results showed the improved lipophilicity of the derivatives through long alkyl chain introduced into its R2 chain.
Keywords: Bisphosphate; Amidated Derivatives; Partition Coefficient; Lipophilicity
Authors: Liang Li; Lijie Zhao
Abstract: The characteristic and mechanism of 2-chloroethanol degradation in a micro-electrolysis contact oxidation system were investigated. The degradation rate of 2-chloroethanol was higher in acid solution than that in neutral or alkaline solution. Addition of activated carbon could make 2-chloroethanol easier be degraded by the surface contact catalysis. The dissolved oxygen in solution could take part in the electrode reaction and intensify the degradation of 2-chloroethanol. Most intermediate products were chloroacetaldehyde, chloroacetic acid, glycollic acid, glyoxylic acid and ethanedioic acid. By the analysis of intermediates of degradation of 2-chloroethanol, its possible degradation pathway is proposed.
Keywords: Micro-electrolysis Contact Oxidation; Degradation; 2-chloroethanol
Authors: Yang Liu; Lijuan Tian; Aiqing Gao
Abstract: Tangshan is not only a strong economic city but also a high energy consumption city in Hebei province. Although Tangshan GDP occupies 1/5 of the provincial total, the energy consumption accounts for 1/3 of the provincial total. Facing the challenge of the low carbon economy, urban environmental problem has already become the bottleneck of future development in Tangshan, which directly influences the competition ability of this city. This paper expounded the general situation of Tangshan, and analyzed the influences of its economic development on urban environment. By strengthening low carbon awareness, planning urban construction with low carbon concept, and developing low carbon industry clusters, we can construct marketing strategy system in Tangshan city, thus promoting its urban competitiveness.
Keywords: Low-carbon Economy; City Marketing; Strategy; Tangshan; Economic Development
Authors: Duoying Zhang; Wenqiang Zhang; Kai Liu
Abstract: To resolve hidden terminal and exposed terminal problems and improve the probability of simultaneous data packet transmissions for multihop mobile ad hoc networks (MANETs), we propose a novel time division multiple access (TDMA) based dual channel reservation (DCR) medium access control (MAC) protocol. The protocol achieves simultaneous collision-free contention reservation access and data packet transmission, and optimal load balance between the packet transmissions on reservation channel (RCH) and traffic channel (TCH) by appropriately adjusting the data rates of the RCH and TCH and guaranteeing the same interval of reservation slot on the RCH as that of data packet transmission slot on the TCH. In addition, the proposed dual reservation mechanisms of reservation slot and contention micro-slot greatly improve channel access and utilization efficiency. Finally, simulation results show that in the presence of the same total data rate, the DCR protocol obviously outperforms the IEEE 802.11 distribution coordination function (DCF) protocol in terms of multiple access performance.
Keywords: Mobile Ad Hoc Networks; Medium Access Control; Dual Channel; Reservation; Hidden Terminal Problem; Exposed Terminal Problem
Authors: Dennis M. Ochieng; David M. Gichoya
Abstract: Success in scaling e-service hierarchy in local authorities from Informational and Interactive systems to Online Transactional Service Systems (OTSS) is hinged on addressing a number of important thematic concerns. It is a foregone conclusion that ICT-enabled service delivery platform offers a landscape of opportunities for improved efficiency and effectiveness in the management and operations of Kenyan local authorities. Therefore, a careful analysis of the underlying themes governing their development and adoption cannot be gained. Basing on a case study of Municipal Council of Eldoret (MCE), this paper presents a thematic analysis of data arising from this study.
Keywords: ICT-enabled Services; Online Transaction Service System; E-service; E-government