作者：
Tang, C. F.;Zhang, R. Q.;Wen, S. Z.;Li, C. F.;Guo, X. F.;...
期刊：
Water Science and Technology,2009年59(8):1487-1493 ISSN：0273-1223
通讯作者：
Liu, Y. G.
作者机构：
[Tang, C. F.; Zhang, R. Q.; Liu, Y. G.; Wen, S. Z.] Cent S Univ Forestry & Technol, Coll Resources & Environm, Changsha 410004, Peoples R China.;[Li, C. F.] Inst Environm Protect Sci, Nanning 530022, Peoples R China.;[Guo, X. F.] Hunan Res Inst Nonferrous Met, Changsha 410015, Peoples R China.
通讯机构：
[Liu, Y. G.] C;Cent S Univ Forestry & Technol, Coll Resources & Environm, Changsha 410004, Peoples R China.
关键词：
cadmium;chemical forms;spermidine;subcellular distribution;Typha latifolia L
摘要：
The effects of foliar spraying with spermidine (Spd) on the subcellular distribution and chemical speciation of Cd in Typha latifolia L. in hydroponic system were investigated. Increased Cd concentration in the medium caused an increase of Cd concentration in all tissues and all subcellular fractions, with the highest Cd level occurring in roots, followed by rhizomes and leaves and the greatest accumulation was in cell walls, soluble fraction and organelle containing fractions ranked next, respectively. The greatest amount of Cd was found in the extraction of 1 mol.L-1 NaCl, followed by 2% HAC, deionized water, 80% ethanol, residues and the least in 0.6 mol.L-1 HCl. The subcellular distribution and different chemical forms of Cd both decreased after Spd application and were more inhibited by 0.25 than 0.50 mmol.L-1 Spd, especially in roots at 0.10 mmol.L-1 Cd treatment. It could be suggested that the retention of Cd in roots, cell walls binding with metal, metal ion compartmentation in vacuoles and Cd forms existing in undissolved and integrated with pectates and protein play an important role in Cd detoxification and Spd could enhance the tolerance of cattail to Cd stress.
作者机构：
[Wu Xiaofu; Zhao Fang; Chen Mingli; Ji Zhihui; Ma Qun] Cent S Univ Forestry & Technol, Inst Environm Sci & Engn, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Wu, XF ] ;Cent S Univ Forestry & Technol, Inst Environm Sci & Engn, Shaoshan S Rd, Changsha 410004, Hunan, Peoples R China.
摘要：
Adsorption experiments of Zn2+ and Cd2+ ions from aqueous solutions onto vermiculite were conducted to test the applicability of two basic functions derived for calculating the change in the Gibbs' free energy (ΔG0) and the chemical potential (Δμ) between the initial and equilibrium states in ion adsorption systems. The functions were deduced on the basis of the thermodynamic principle that the chemical potentials of the reactants and products of a physicochemical reaction should be equal in the equilibrium state and, consequently, the change in the Gibbs' free energy between the initial and equilibrium states of the reaction should be equal to the sum of the initial molar quantity of each reactant multiplied by its change in chemical potential. The results of the analysis conducted indicate that the two functions considered could well be used not only for calculating ΔG0 and Δμ but also for determining the adsorption capacity of an adsorbent under the conditions considered.
摘要：
微生物是污水净化的主要作用者之一.采用变性梯度凝胶电泳(denaturing gradient gel electrophresis,DGGE)方法培育和鉴定土壤微生物具有可靠性强、重复性好、方便快捷等优点,已被广泛应用于环境科学和污染防治研究领域.综述了基于PCR-DGGE技术的基本原理、关键环节及其在微生物多样性研究中的应用,同时就其自身存在的不足进行了评价并提出了解决方案.
摘要：
Selective laser sintering (SLS) is an attractive rapid prototyping (RP) technology capable of manufacturing parts from a variety of materials. However, the wider application of SLS has been limited, due to their accuracy. This paper presents an optimal method to determine the best processing parameter for SLS by minimizing the shrinkage. According to the nonlinear and multitudinous processing parameter feature of SLS, the theory and the algorithms of the neural network are applied for studying SLS process parameters. The process is modeled and described by neural network based on experiment. Moreover, the optimum process parameters, such as layer thickness, hatch spacing, laser power, scanning speed, work surroundings temperature, interval time, and scanning mode are obtained by adopting the genetic algorithm based on the neural network model. The optimum process parameters will be benefit for RP users in creating RP parts with a higher level of accuracy.
摘要：
In order to properly conserve the historical documents it is critical to continuously measure some parameters, such as temperature, relative humidity, light and, also, pollutants, either in repository or bookrack rooms. The deployment of a Wireless Sensor Network in a library can help implementing these measurements in real-time, continuously, and in a much easier and cheap way. In this paper, we present a practical testbed deployed in the Hunan library, located in Changsha, China. This work is being developed in the context of an ongoing project on library environmental and structural monitoring using Wireless Sensor Networks. The experimental testbed is described, as well as all the problems identified.
期刊：
CCDC 2009: 21ST CHINESE CONTROL AND DECISION CONFERENCE, VOLS 1-6, PROCEEDINGS,2009年:4732-+
通讯作者：
Liu Yong-Min
作者机构：
[Liu Yong-Min] Cent South Univ Forestry & Technol, Coll Vocat Technol, Changsha 410004, Peoples R China.;[Liu Yong-Min; Jiang Xin-Hua; Nian Xiao-Hong] Cent S Univ, Sch Informat Sci & Engn, Changsha 410075, Peoples R China.
通讯机构：
[Liu Yong-Min] C;Cent South Univ Forestry & Technol, Coll Vocat Technol, Changsha 410004, Peoples R China.
关键词：
Max-min Fairness;Datagram Congestion Control Protocol;congestion control;wireless sensor networks
摘要：
This TCP is primarily designed for wired networks and became very efficient and robust with years of enhancements. However, experiments and research showed that TCP's congestion control algorithm performs very poorly over Wireless Sensor Networks (WSN) with severe unfairness among flows. Because the deployment of a sensor network causes unpredictable patterns of connectivity and varied node density, resulting in uneven bandwidth provisioning on the forwarding paths. This paper studies TCP's fairness issues in WSNs, and designs an Extended congestion control algorithm based on the characteristics of the WSNs. The protocol is designed as extension to DCCP (Datagram Congestion Control Protocol) with a new congestion control component. We also implemented this congestion control algorithm in NS2. Simulation results show improvements on fairness achieved by using Extend congestion control algorithm.
