香溪河沉积物中磷形态的垂向分布特征与相关分析

为揭示三峡库区沉积物中磷形态的分布特征及其与沉积物理化指标的相关性,本文以香溪河为例,沿河流自上游向下采集沉积物样,应用五步连续提取法分层测定柱状沉积物中的磷形态,并对pH、有机质、粒度等与磷形态间进行相关性分析.结果表明:在水平方向,表层沉积物(0~4cm)的总磷(TP)排序为中游(XX06)上游(XX08)干支流交汇处(CJXX)下游(XX01);在垂向分布上,中上游(XX08和XX06)各形态磷含量整体沿垂向递减,而下游和交汇处(XX01和CJXX)钙结合态磷(HCl-P)沿垂向递增.香溪河沉积物TP的含量范围为715~947mg/kg,HCl-P构成沉积物中磷的主要部分.生物有效性磷(BAP)占TP含量的20%~48%,CJXX沉积物中的BAP含量略低于支流.不同样点沉积物中磷形态与环境因素的相关性并不一致,中上游沉积物TP与BAP显著相关,氧化还原敏感性磷(BD-P)或BAP受氧化还原电位(Eh)影响较大;而下游和干支流交汇处的主要影响因素为pH值,BAP主要由金属氧化物结合态磷(NaOH-P)组成,二者相关性显著.在CJXX,伊利石含量随粒径的增加而减少,与石英和白云石变化规律相反.     

锁磷剂对府河底泥磷释放的影响

选用美国新一代锁磷剂SAE,进行了45、90、180g/m2 3种不同剂量的锁磷剂控制府河底泥磷释放的模拟实验研究.结果表明,SAE降低了府河河道底泥上覆水中的总磷(TP)、可溶性正磷酸盐(SRP)、可溶性总磷酸盐(DTP)含量,添加90g/m2和180g/m2 SAE的抑磷率达到80%以上且效果稳定.底泥中向上覆水释放的磷主要来自于可交换态磷(Ex-P)和铁铝结合态磷(NaOH-P),钙结合态磷(HCl-P)含量变化不显著,SAE的添加使得底泥中的磷形态发生了转变,Ex-P和NaOH-P向HCl-P转化,使得稳定态磷占比增大,降低了沉积物磷向上覆水释放的风险.     

杞麓湖表层沉积物磷形态的分布特征

对杞麓湖的表层沉积物,采取SMT法,测定其中的总磷(TP)、无机磷(IP)、有机磷(Org-P)、铁/铝磷(Fe/Al-P)、钙磷(Ca/P)、松散结合态磷(L-P)六种形态的磷,分析了表层沉积物形态磷丰度特征,空间分布特征,并且分析了不同形态磷之间以及烧失量的相关性。结果表明,杞麓湖表层沉积物中IP、Org-P、Fe/Al-P、Ca-P与TP呈极显著的正相关关系,L-P与TP之间无明显相关性。     

天津于桥水库上游河流表层沉积物不同形态磷的空间分布

为了解天津于桥水库上游河流表层沉积物中磷形态的空间分布规律,采用SMT法对于桥水库上游流域33个样点的河流表层沉积物中不同形态的磷进行连续分级提取和空间统计分析,探讨沉积物中各形态磷的空间聚集特征及其与土地利用的关系.结果表明:(1)于桥水库上游流域河流表层沉积物中,总磷(TP)含量为425.94~3412.96 mg/kg,TP中各形态磷含量的顺序为:钙磷(Ca-P)有机磷(OP)铁铝磷(Fe/Al-P).OP和Fe/Al-P在各样点间的含量差异较大,其变异系数分别为71.92%和100.48%.(2)全局自相关分析发现,5种形态的磷中,只有OP和Fe/Al-P在空间分布上存在聚集模式,其对应的Moran′I指数分别为0.27和0.19;自相关分析结果表明,OP和Fe/Al-P热点区域均位于流域中下游村镇,冷点区域在流域上游山区.(3)相关性分析结果表明,TP、无机磷和Ca-P主要存在于粗颗粒沉积物中,含量与砂的质量分数均呈显著正相关;Fe/Al-P和OP含量均与村镇分布和不透水面指数呈显著正相关,与林地和高程呈显著负相关.     

北部湾南部沉积物中磷的形态特征及环境意义

采用SEDEX方法对2006年7月北部湾南部海区调查过程中采集的表层沉积物中的总磷(TP)及各种磷的赋存形态进行了系统性分析,同时结合沉积物及上覆水的环境参数,讨论了磷的地球化学特征.磷(P)的6种地球化学赋存形态分为:弱吸附态(Ads-P)、铁结合态(Fe-P)、自生磷灰石及钙结合态(Ca-P)、碎屑态(De-P)、有机态(OP)及硅酸盐态(SIF-P).研究表明,沉积物的TP主要源于海区内部生物地球化学过程,陆源输入影响较弱,具有保守性;Ca-P是上覆水体中活性磷酸盐(DIP)的汇;SIF-P是上覆水体中颗粒磷(PP)的汇;沉积物的粒度(GSL)是控制P形态含量重要因子;盐度(S)是影响Fe-P的含量变化的重要因子;Ca-P、De-P、SIF-P是沉积物中的"惰性磷",Ads-P、Fe-P、OP是沉积物中的"活性磷".     

巢湖城市内河沉积物不同形态磷空间分布特征

对巢湖市城市内河的表层沉积物及柱状沉积物进行了采样,并采用修正后的标准测试程序( SMT)测定了其中的总磷(TP)、无机磷(IP)、有机磷(OP)、铁/铝磷(Fe/Al-P)和钙磷(Ca-P),分析了各形态磷之间以及与沉积物有机质之间的相关性.结果表明,表层沉积物TP的质量分数在832.09～2 572.41 mg·kg-1之间,其中以Fe/Al-P为主,占总磷的比例为42.0％～62.3％.采样点各形态磷随深度的增加总体呈现先升高后下降的趋势,但不同采样点出现峰值的深度有所不同,这种空间分布特征能够较好反映周边环境现状和入河污染负荷的变化.不同深度沉积物中各形态磷之间存在极显著的相关性(概率水平P＜0.01),各形态磷与有机质也存在极其显著的正相关.     

浙江近岸海域表层沉积物中磷的存在形态及其分布特征

运用SEDEX方法分析了浙江近岸海域表层沉积物中总磷(TP)及磷在各提取相的含量和分布.研究结果表明,表层沉积物中TP含量为432.2～846.1 mg/kg,平均为(533.2±90.1) mg/kg;弱吸附态磷(Ads-P)、铁结合态磷(Fe-P)、自生磷灰石及钙结合态磷(Ca-P)、碎屑态磷(De-P)和有机磷(OP)平均含量分别为6.2,93.2,12.4,295.0和66.5 mg/kg,分别占TP的1.2％,17.7％,2.4％,56.7％,和12.7％.沉积物的Ads-P、Ca-P和OP与其粒度和有机碳含量呈显著正相关,De-P则呈负相关.各站位沉积物中磷在不同提取相中的含量差异较大,与沉积物的陆源输入、沉积物粒径及沉积海域的水动力条件等因素有关.     

獐子岛附近海域沉积物中氮和磷的分布来源及污染风险评价

【目的】为探讨北黄海獐子岛附近海域氮、磷的来源及其污染风险状况,对该海域表层沉积物中氮、磷的形态和分布特征进行分析。【方法】采用K2S2O8氧化法和HCl浸取法对獐子岛附近海域13个站位的表层沉积物中总氮(TN)、总磷(TP)及其无机和有机态的含量进行分析,并采用单因子标准指数法对氮、磷的污染水平进行评价。【结果】獐子岛附近海域沉积物中TN和TP的含量分别为0.192~1.357 mg/g和0.302~0.489mg/g,有机氮(ON)和无机磷(IP)是表层沉积物中氮和磷的主要存在形式,分别占TN与TP的90.93%和82.84%。沉积物中TN和TP在研究区域南部含量较高,这与沉积物粒度密切相关;而ON、有机磷(OP)两者都与有机碳(TOC)含量具有显著相关性,说明它们具有相似的来源。单因子标准指数法分析表明獐子岛附近海域沉积物中TP含量较低,标准指数均小于1;而TN含量相对较高,其标准指数为0.35~2.47。【结论】獐子岛附近海域沉积物中氮为陆源和自生混合来源,而磷主要是陆源输入;海域沉积物环境受到氮的污染。     

北民湖沉积物氮、磷形态竖向分布研究

为了解养殖类湖区不同深度沉积物中氮、磷形态的分布状况,选取典型养殖湖区北民湖为研究对象,运用柱状取样法将沉积物进行分层,探讨不同深度沉积物中氮、磷形态的分布特征.结果显示:北民湖沉积物中有机氮为主要氮形态,约占TN的94.53%,无机磷为主要磷形态,约占TP的76.10%.无机磷中,又以Fe/Al-P含量相对最高,约为IP的66.05%,而Ca-P和OP含量均相对较低.沉积物中TN随沉积深度增加呈下降趋势,硝态氮随沉积深度的增加呈先下降后稳定的趋势,而氨氮呈先增大后减小的趋势;沉积物中TP、IP、Fe/Al-均随沉积深度增加呈明显下降趋势,而Ca-P、OP相对较为稳定.     

南四湖表层沉积物中N的形态及其分布特征

采用分级浸取分离法分别对南四湖的7个表层沉积物样品中的离子交换态氮(IEF-N)、弱酸可浸取态氮(WAEF-N)、强碱可浸取态氮(SAEF-N)及强氧化剂可浸取态氮(SOEF-N)进行提取,并将沉积物的N划分为可转化态氮(TTN)和非转化态氮(NTN),对南四湖表层沉积物中各形态N含量及其分布特征和相关环境因素进行了分析。分析结果表明,南四湖上下级湖区表层沉积物中除SAEF-N外,TN及各形态N含量差异显著且上级湖明显高于下级湖区;下级湖表层沉积物中TTN占TN含量的比列明显高于上级湖;南四湖沉积物中N元素成分主要结合在沉积物中的细粒黏土成分中;南四湖上覆水中TN和NH4+-N与表层沉积物中TN和各形态N没有表现出显著的正相关关系,这说明南四湖湖水中的N元素主要来源于入湖河流;沉积物中的氮磷比在1.5～4.5,低于Redfield指数,上覆水中的氮磷比为13.7～24.1,高于Redfield指数,进一步说明南四湖目前水体中的N、P元素主要来自于入湖河流;沉积物中的TN含量在近10 a间下降很大且P仍然是南四湖湖最主要的限制性营养元素。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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