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Necessary and sufficient conditions for moderate deviations of dependent random variables with heavy tails 被引量:44
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作者 LIU Li School of Mathematics and Statistics,Wuhan University,Wuhan 430072,China 《Science China Mathematics》 SCIE 2010年第6期1421-1434,共14页
This paper studies the moderate deviations of real-valued extended negatively dependent(END) random variables with consistently varying tails.The moderate deviations of partial sums are first given.The results are the... This paper studies the moderate deviations of real-valued extended negatively dependent(END) random variables with consistently varying tails.The moderate deviations of partial sums are first given.The results are then used to establish the necessary and sufficient conditions for the moderate deviations of random sums under certain circumstances. 展开更多
关键词 MODERATE deviation extended negative dependence consistently VARYING TAIL random sum
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论我国《消费者权益保护法》中的惩罚性赔偿 被引量:37
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作者 董文军 《当代法学》 北大核心 2006年第2期69-74,共6页
我国在1994年开始实施的《中华人民共和国消费者权益保护法》中规定了惩罚性损害赔偿制度,该制度具有惩罚经营者的欺诈行为和激励消费者维权的功能。但在司法实践中围绕该制度的适用却出现了问题,主要表现为知假买假者能否要求惩罚性赔... 我国在1994年开始实施的《中华人民共和国消费者权益保护法》中规定了惩罚性损害赔偿制度,该制度具有惩罚经营者的欺诈行为和激励消费者维权的功能。但在司法实践中围绕该制度的适用却出现了问题,主要表现为知假买假者能否要求惩罚性赔偿,对适用惩罚性赔偿的条件———“欺诈”应如何理解以及惩罚性赔偿的数额等问题。认可知假买假者的消费者身份,对“欺诈”作有别于《民法通则》与《合同法》中的解释以及重新确定惩罚性赔偿的额度将有助于发挥惩罚性赔偿制度的功能。 展开更多
关键词 惩罚性赔偿 知假买假者 欺诈 数额
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河网水流数值模拟方法研究 被引量:22
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作者 吴作平 杨国录 甘明辉 《水科学进展》 EI CAS CSCD 北大核心 2003年第3期350-353,共4页
讨论了河网概化的一般原则,并在分析单一河段水流数学模型的基础上,建立了可以适用于一般河网体系水流数值计算的数学模型,并采用荆江—洞庭湖的相关资料进行了验证。结果表明,模型的计算值与实测值吻合较好,说明该模型具有较好的适用性。
关键词 河网 水流 数值模拟 概化 节点
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Neighbor Sum Distinguishing Total Colorings of Graphs with Bounded Maximum Average Degree 被引量:26
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作者 Ai Jun DONG Guang Hui WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第4期703-709,共7页
A proper [h]-total coloring c of a graph G is a proper total coloring c of G using colors of the set [h] ={1, 2,..., h}. Let w(u) denote the sum of the color on a vertex u and colors on all the edges incident to u. ... A proper [h]-total coloring c of a graph G is a proper total coloring c of G using colors of the set [h] ={1, 2,..., h}. Let w(u) denote the sum of the color on a vertex u and colors on all the edges incident to u. For each edge uv ∈ E(G), if w(u) ≠ w(v), then we say the coloring c distinguishes adjacent vertices by sum and call it a neighbor sum distinguishing [h]-total coloring of G. By tndi∑ (G), we denote the smallest value h in such a coloring of G. In this paper, we obtain that G is a graph with at least two vertices, if mad(G) 〈 3, then tndi∑ (G) ≤k + 2 where k = max{△(G), 5}. It partially confirms the conjecture proposed by Pilgniak and Wolniak. 展开更多
关键词 Total coloring neighbor sum distinguishing total colorings average degree
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Neighbor sum distinguishing total colorings of K4-minor free graphs 被引量:24
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作者 Hualong LI Bingqiang LIU Guanghui WANG 《Frontiers of Mathematics in China》 SCIE CSCD 2013年第6期1351-1366,共16页
A total [k]-coloring of a graph G is a mapping φ: V(G) U E(G) →{1, 2, ..., k} such that any two adjacent elements in V(G)UE(G) receive different colors. Let f(v) denote the sum of the colors of a vertex v... A total [k]-coloring of a graph G is a mapping φ: V(G) U E(G) →{1, 2, ..., k} such that any two adjacent elements in V(G)UE(G) receive different colors. Let f(v) denote the sum of the colors of a vertex v and the colors of all incident edges of v. A total [k]-neighbor sum distinguishing-coloring of G is a total [k]-coloring of G such that for each edge uv E E(G), f(u) ≠ f(v). By tt [G, Xsd( J, we denote the smallest value k in such a coloring of G. Pilniak and Woniak conjectured X'sd(G) 〈 A(G) + 3 for any simple graph with maximum degree A(G). This conjecture has been proved for complete graphs, cycles, bipartite graphs, and subcubic graphs. In this paper, we prove that it also holds for Ka-minor free graphs. Furthermore, we show that if G is a Ka-minor flee graph with A(G) 〉 4, then " Xnsd(G) 〈 A(G) + 2. The bound A(G) + 2 is sharp. 展开更多
关键词 K4-minor free graph neighbor sum distinguishing (nsd)
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国外水泵研究现状概述 被引量:17
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作者 严敬 杨小林 《排灌机械》 2003年第5期1-3,共3页
以丰富的材料为基础,概括性地评价了西方近年中在水泵技术各研究领域,如流场计算、汽蚀机理、振动、无泄漏密封等方面的研究现状及成果,这些资料将为国内水泵技术人员的产品开发、科研活动提供有益的启发和借鉴。
关键词 水泵 流场计算 汽蚀机理 振动 无泄漏密封 研究现状
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基于Minkowski Sum的热泵负荷调度灵活性聚合方法 被引量:20
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作者 栗子豪 李铁 +3 位作者 吴文传 张伯明 姜枫 崔岱 《电力系统自动化》 EI CSCD 北大核心 2019年第5期14-23,共10页
随着"煤改电"工程的实施,配电网中的热泵负荷显著增加。站在热泵用户的角度,采用合作博弈模式联盟热泵的调度灵活性参与配电网日前调度。为准确刻画该热泵负荷集群的聚合灵活性,采用基于Minkowski Sum的约束空间叠加方法,并... 随着"煤改电"工程的实施,配电网中的热泵负荷显著增加。站在热泵用户的角度,采用合作博弈模式联盟热泵的调度灵活性参与配电网日前调度。为准确刻画该热泵负荷集群的聚合灵活性,采用基于Minkowski Sum的约束空间叠加方法,并通过寻找其最大内接正方体或直角棱锥简化约束而将热泵集群刻画为"虚拟同步机"或"虚拟储能"模型。进一步地,提出基于近似Shapley Value的用户间收益分配方法。基于IEEE 33节点系统的算例证明了本方法的有效性。 展开更多
关键词 主动配电网 热泵 日前调度 虚拟同步机 虚拟储能 MINKOWSKI sum Shapley VALUE
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FORWARD-BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS, LINEAR QUADRATIC STOCHASTIC OPTIMAL CONTROL AND NONZERO SUM DIFFERENTIAL GAMES 被引量:13
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作者 WUZhen 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2005年第2期179-192,共14页
In this paper, we use the solutions of forward-backward stochastic differential equations to get the explicit form of the optimal control for linear quadratic stochastic optimal control problem and the open-loop Nash ... In this paper, we use the solutions of forward-backward stochastic differential equations to get the explicit form of the optimal control for linear quadratic stochastic optimal control problem and the open-loop Nash equilibrium point for nonzero sum differential games problem. We also discuss the solvability of the generalized Riccati equation system and give the linear feedback regulator for the optimal control problem using the solution of this kind of Riccati equation system. 展开更多
关键词 stochastic differential equations stochastic optimal control riccatiequation nonzero sum stochastic differential game
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Slope stability analysis under seismic load by vector sum analysis method 被引量:15
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作者 Mingwei Guo Xiurun Ge Shuilin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第3期282-288,共7页
The vibration characteristics and dynamic responses of rock and soil under seismic load can be estimated with dynamic finite element method (DFEM). Combining with the DFEM, the vector sum analysis method (VSAM) is... The vibration characteristics and dynamic responses of rock and soil under seismic load can be estimated with dynamic finite element method (DFEM). Combining with the DFEM, the vector sum analysis method (VSAM) is employed in seismic stability analysis of a slope in this paper. Different from other conventional methods, the VSAM is proposed based on the vector characteristic of force and current stress state of the slope. The dynamic stress state of the slope at any moment under seismic load can he obtained by the DFEM, thus the factor of safety of the slope at any moment during earthquake can be easily obtained with the VSAM in consideration of the DFEM. Then, the global stability of the slope can be estimated on the basis of time-history curve of factor of safety and reliability theory. The VSAM is applied to a homogeneous slope under seismic load. The factor of safety of the slope is 1.30 under gravity only and the dynamic factor of safety under seismic load is 1.21. The calculating results show that the dynamic characteristics and stability state of the slope with input ground motion can be actually analyzed. It is believed that the VSAM is a feasible and practical approach to estimate the dynamic stability of slopes under seismic load. 展开更多
关键词 slope stability vector sum analysis method (VSAM) seismic load dynamic finite element method (DFEM)
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Chinese Offshore RMB Currency and Bond Markets:The Role of Hong Kong 被引量:15
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作者 Hung-Gay Fung Jot Yau 《China & World Economy》 SCIE 2012年第3期107-122,共16页
This paper discusses the role of Hong Kong in China's grand scheme to build up the RMB as a global reserve currency. We highlight the economic importance of Hong Kong to China in terms of channeling foreign direct in... This paper discusses the role of Hong Kong in China's grand scheme to build up the RMB as a global reserve currency. We highlight the economic importance of Hong Kong to China in terms of channeling foreign direct investment into China, some of which, in the future, will be denominated in the RMB. We discuss the development of China's RMB currency swap and deposit markets in Hong Kong. These offshore markets enable the RMB to trade freely, setting the stage for the RMB to become fully convertible and allowing market forces to play a role in pricing the value of the RMB, and help in the development of the RMB-denominated bond (or dim sum bond) market in Hong Kong. Finally, we present evidence of the phenomenal growth of the dim sum bond market in Hong Kong, which can further enhance and strengthen the use of the RMB outside China. 展开更多
关键词 dim sum bond FDI offshore market reserve currency RMB
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Gaussian Sum PHD Filtering Algorithm for Nonlinear Non-Gaussian Models 被引量:14
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作者 尹建君 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第4期341-351,共11页
A new multi-target filtering algorithm, termed as the Gaussian sum probability hypothesis density (GSPHD) filter, is proposed for nonlinear non-Gaussian tracking models. Provided that the initial prior intensity of ... A new multi-target filtering algorithm, termed as the Gaussian sum probability hypothesis density (GSPHD) filter, is proposed for nonlinear non-Gaussian tracking models. Provided that the initial prior intensity of the states is Gaussian or can be identified as a Gaussian sum, the analytical results of the algorithm show that the posterior intensity at any subsequent time step remains a Gaussian sum under the assumption that the state noise, the measurement noise, target spawn intensity, new target birth intensity, target survival probability, and detection probability are all Gaussian sums. The analysis also shows that the existing Gaussian mixture probability hypothesis density (GMPHD) filter, which is unsuitable for handling the non-Gaussian noise cases, is no more than a special case of the proposed algorithm, which fills the shortage of incapability of treating non-Gaussian noise. The multi-target tracking simulation results verify the effectiveness of the proposed GSPHD. 展开更多
关键词 signal processing Gaussian sum probability hypothesis density SIMULATION nonlinear non-Gaussian TRACKING
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成都市14个区县医疗卫生资源配置与利用的RSR评价 被引量:12
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作者 杨建南 李世云 +2 位作者 刘勇华 杨柳桦 钟鸣 《成都医学院学报》 CAS 2008年第3期204-207,共4页
目的评价成都市各区县医疗卫生资源的配置与利用情况。方法采用秩和比法(RSR)对成都市2006年14个区县医院卫生资源的配置和利用情况进行综合评价。结果14个区县卫生医院卫生资源的配置与利用是不平衡的,个别邻近成都市中心城区的区县,... 目的评价成都市各区县医疗卫生资源的配置与利用情况。方法采用秩和比法(RSR)对成都市2006年14个区县医院卫生资源的配置和利用情况进行综合评价。结果14个区县卫生医院卫生资源的配置与利用是不平衡的,个别邻近成都市中心城区的区县,医疗卫生资源配置较高,但是其利用效率不高;而个别地处边远地区的区县,其医疗卫生资源配置较少,却获得了较高的利用效率。结论①应当结合区域卫生规划,根据影响卫生服务需要和利用的因素,合理优化配置医疗卫生资源。②加强对医疗卫生机构的监管,提高医疗服务质量和工作效率,提高医疗服务供给的效率与公平性。 展开更多
关键词 医疗卫生资源 资源配置 资源利用 秩和比法(Rank sum RATIO RSR)
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开放条件下贸易利益内涵的界定及其相关理论评述 被引量:10
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作者 隋福民 饶鹏 《国际贸易问题》 CSSCI 北大核心 2007年第1期121-126,共6页
长期以来,参与国际分工与贸易的各国是否能从国际贸易中获得利益这一问题,一直是理论界争论的焦点,因此,本文从狭义的贸易利益与广义的贸易利益,真实的贸易利益与潜在的贸易利益,贸易利益与地区经济一体化,贸易利益与不完全竞争、规模... 长期以来,参与国际分工与贸易的各国是否能从国际贸易中获得利益这一问题,一直是理论界争论的焦点,因此,本文从狭义的贸易利益与广义的贸易利益,真实的贸易利益与潜在的贸易利益,贸易利益与地区经济一体化,贸易利益与不完全竞争、规模报酬递增四个角度作了一些评述。本文认为,只有在一定的条件之下,一国才可以从开放的国际贸易中获得贸易利益,最终实现一国经济持续增长的目标,如政府在开放经济条件下采取适当的贸易政策、在开放贸易情况下补偿受损人群的利益、参与区域经济一体化等。 展开更多
关键词 贸易利益 不完全竞争 规模报酬递增 转移支付(Lump sum Transfers) 区域经济一体化
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Parameters inversion of high central core rockfill dams based on a novel genetic algorithm 被引量:14
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作者 ZHOU Wei LI Shao Lin +3 位作者 MA Gang CHANG Xiao Lin MA Xing ZHANG Chao 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第5期783-794,共12页
Parameters identification of rockfill materials is a crucial issue for high rockfill dams. Because of the scale effect, random sampling and sample disturbance, it is difficult to obtain the actual mechanical propertie... Parameters identification of rockfill materials is a crucial issue for high rockfill dams. Because of the scale effect, random sampling and sample disturbance, it is difficult to obtain the actual mechanical properties of rockfill from laboratory tests. Parameters inversion based on in situ monitoring data has been proven to be an efficient method for identifying the exact parameters of the rockfill. In this paper, we propose a modified genetic algorithm to solve the high-dimension multimodal and nonlinear optimal parameters inversion problem. A novel crossover operator based on the sum of differences in gene fragments(So DX) is proposed, inspired by the cloning of superior genes in genetic engineering. The crossover points are selected according to the difference in the gene fragments, defining the adaptive length. The crossover operator increases the speed and accuracy of algorithm convergence by reducing the inbreeding and enhancing the global search capability of the genetic algorithm. This algorithm is compared with two existing crossover operators. The modified genetic algorithm is then used in combination with radial basis function neural networks(RBFNN) to perform the parameters back analysis of a high central earth core rockfill dam. The settlements simulated using the identified parameters show good agreement with the monitoring data, illustrating that the back analysis is reasonable and accurate. The proposed genetic algorithm has considerable superiority for nonlinear multimodal parameter identification problems. 展开更多
关键词 rockfill dam parameters back analysis genetic algorithm crossover operator sum of differences in gene fragments
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On Mues Conjecture and Picard Values 被引量:3
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作者 王跃飞 《Science China Mathematics》 SCIE 1993年第1期28-35,共8页
Suppose that f is transcendental meromorphic in the plane. Then (ⅰ) sum from ∈C=1 to δ(α,f^(k))≤1 holds for all k≥0 with at most four exceptions of k; (ⅱ) for n≥3,k≥0, (f^n)^(k) assumes all finite values (pos... Suppose that f is transcendental meromorphic in the plane. Then (ⅰ) sum from ∈C=1 to δ(α,f^(k))≤1 holds for all k≥0 with at most four exceptions of k; (ⅱ) for n≥3,k≥0, (f^n)^(k) assumes all finite values (possibly except zero) infinitely often. (ⅰ) affirms a conjecture of Mues for almost every positive integers. And (ⅱ) is a general Picard theorem. Some other results are also obtained. 展开更多
关键词 DEFICIENCY sum Pieard value.
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On error distance of Reed-Solomon codes 被引量:9
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作者 LI YuJuan WAN DaQing 《Science China Mathematics》 SCIE 2008年第11期1982-1988,共7页
The complexity of decoding the standard Reed-Solomon code is a well known open prob-lem in coding theory. The main problem is to compute the error distance of a received word. Using the Weil bound for character sum es... The complexity of decoding the standard Reed-Solomon code is a well known open prob-lem in coding theory. The main problem is to compute the error distance of a received word. Using the Weil bound for character sum estimate, we show that the error distance can be determined precisely when the degree of the received word is small. As an application of our method, we give a significant improvement of the recent bound of Cheng-Murray on non-existence of deep holes (words with maximal error distance). 展开更多
关键词 Reed-Solomon code error distance deep hole character sum 30P12 32C12
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Resonance between automorphic forms and exponential functions 被引量:9
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作者 REN XiuMin1,& YE YangBo1,2 1School of Mathematics,Shandong University,Jinan 250100,China 2Department of Mathematics,The University of Iowa,Iowa City,Iowa 52242-1419,USA 《Science China Mathematics》 SCIE 2010年第9期2463-2472,共10页
Let f be a holomorphic cusp form of weight k for SL2(Z) and λf(n) its n-th Fourier coefficient.In this paper,the exponential sum X【n 2X λf(n)e(αnβ) twisted by Fourier coefficients λf(n) is proved toh ave a main ... Let f be a holomorphic cusp form of weight k for SL2(Z) and λf(n) its n-th Fourier coefficient.In this paper,the exponential sum X【n 2X λf(n)e(αnβ) twisted by Fourier coefficients λf(n) is proved toh ave a main term of size |λf(q)|X3/4 when β = 1/2 and α is close to ±2√q,q ∈ Z,and is smaller otherwise for β 【 3/4.This is a manifestation of the resonance spectrum of automorphic forms for SL2(Z). 展开更多
关键词 automorphic FORM EXPONENTIAL sum RESONANCE
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ON THE EXISTENCE OF ZERO POINTS OF A CONTINUOUS FUNCTION 被引量:7
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作者 J.M. SorianoDepartamento de Andlisis Matematico, Facultad de Matemdticas, Universidad de Sevilla, Aptdo. 1160, Sevilla 41080, Spain 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期171-177,共7页
A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to... A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to the zero point. 展开更多
关键词 Zero point continuation methods Banach fixed point theorem HOMOTOPY topological direct sum ISOMORPHISM k-contractive mapping
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How does innovation's tail risk determine marginal tail risk of a stationary financial time series? 被引量:7
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作者 YU Bosco W. T. PANG W. K. 《Science China Mathematics》 SCIE 2004年第3期321-338,共18页
We discuss the relationship between the marginal tail risk probability and the innovation'stail risk probability for some stationary financial time series models.We first give the main results on the tail behavior... We discuss the relationship between the marginal tail risk probability and the innovation'stail risk probability for some stationary financial time series models.We first give the main results on the tail behavior of a class of infinite weighted sums of random variableswith heavy-tailed probabilities. And then, the main results are applied tothree important types of time series models:infinite order moving averages, the simple bilinear time series and the solutions of stochasticdifference equations. The explicit formulas are given to describe how the marginaltail probabilities come from the innovation's tail probabilities for these time series.Our results can be applied to the tail estimation of time series and are useful for risk analysis in finance. 展开更多
关键词 risk analysis INFINITE weighted sum moving average BILINEAR model stochastic difference equation TAIL probability VAGUE convergence.
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High-performance size exclusion chromatography with a multi-wavelength absorbance detector study on dissolved organic matter characterisation along a water distribution system 被引量:7
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作者 Huiping Huang Emma Sawade +3 位作者 David Cook Christopher W.K.Chow Mary Drikas Bo Jin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第6期235-243,共9页
This study examined the associations between dissolved organic matter(DOM) characteristics and potential nitrification occurrence in the presence of chloramine along a drinking water distribution system. High-perfor... This study examined the associations between dissolved organic matter(DOM) characteristics and potential nitrification occurrence in the presence of chloramine along a drinking water distribution system. High-performance size exclusion chromatography(HPSEC) coupled with a multiple wavelength detector(200–280 nm) was employed to characterise DOM by molecular weight distribution, bacterial activity was analysed using flow cytometry, and a package of simple analytical tools, such as dissolved organic carbon, absorbance at 254 nm, nitrate,nitrite, ammonia and total disinfectant residual were also applied and their applicability to indicate water quality changes in distribution systems were also evaluated. Results showed that multi-wavelength HPSEC analysis was useful to provide information about DOM character while changes in molecule weight profiles at wavelengths less than 230 nm were also able to be related to other water quality parameters. Correct selection of the UV wavelengths can be an important factor for providing appropriate indicators associated with different DOM compositions. DOM molecular weight in the range of 0.2–0.5 kDa measured at210 nm correlated positively with oxidised nitrogen concentration(r = 0.99), and the concentrations of active bacterial cells in the distribution system(r = 0.85). Our study also showed that the changes of DOM character and bacterial cells were significant in those sampling points that had decreases in total disinfectant residual. HPSEC-UV measured at210 nm and flow cytometry can detect the changes of low molecular weight of DOM and bacterial levels, respectively, when nitrification occurred within the chloraminated distribution system. 展开更多
关键词 HPSEC-UV Distribution system DOM sum of nitrate and nitrite concentration
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