桥墩湖浮游植物调查以及鲢、鳙鱼产力的研究

2011年9月在湖北省对养殖水体桥墩湖的浮游藻类进行了调查,共鉴定出浮游藻类5门40属43种.浮游藻类的平均细胞数量为1.02×108个/L,平均生物量为14.56 mg/L.浮游动物29种,平均数量和生物量分别为13 189.62个/L、15.71 mg/L.其中中华小尖头藻(Raphidiopsis sinensia)、假鱼腥藻(Pseudanabaena sp.)和中华平裂藻(Merismopedia sinica)占到了总的浮游藻类细胞密度的80;.从生物量来说,优势种为硅藻门的尖针杆藻(Synedra acus),达到了总生物量的15.64;,以及浮游动物的轮虫为74.64;.     

南美白对虾大棚高效养殖池塘理化因子与浮游藻类动态变化研究

本文设计大棚高效养殖池塘养殖南美白对虾。对同一大棚内4口池塘的养殖效果和养殖水体中部分理化因子、浮游藻类进行监测。结果表明:理化因子方面,水温在16.85~31.75℃之间波动,整体呈上升趋势;pH在7.41~9.36之间波动,峰值出现在养殖初期,之后逐渐下降到一个稳定水平;溶解氧保持在5 mg/L以上;氨氮含量在0.20~6.56 mg/L之间,峰值出现在5月下旬至6月上旬;亚硝酸盐氮含量在0.002~29.5 mg/L之间,在5月底至6月初出现爆发性增加;浮游藻类方面,养殖池溏出现的浮游藻类6门36种(属),其中绿藻门13种(属),甲藻门6种(属),硅藻门6种(属),金藻门6种(属),裸藻门3种(属),蓝藻门2种(属)。优势种共9种(属),绿藻门的优势种为拟衣藻、卵囊藻、球衣藻,硅藻门的优势种为小环藻、菱形藻,甲藻门的优势种为裸甲藻,金藻门的优势种为小土栖藻,蓝藻门的优势种为色球藻、颤藻,其中色球藻的优势度指数明显高于其他优势种,整个养殖周期中浮游藻类的细胞总数在3.07×10~6~729.44×10~6 cell/L之间;养殖效果方面,4口池塘平均产量为1 335±25.5 kg/667 m~2,平均成活率为77.88%±1.49%,平均饵料系数为1.51±0.04。     

镜湖角突臂尾轮虫种群增长参数的克隆多样性

以采自芜湖市镜湖水体中的11个角突臂尾轮虫(Brachionus angularis)克隆为对象,在(25±1)℃,0.5×10~6、1.0×10~6和2.0×10~6个细胞/m L的斜生栅藻(Scenedemus obliquus)密度下,应用群体累积培养法研究了角突臂尾轮虫种群增长参数的克隆多样性.结果表明,轮虫的种群增长率、最大种群密度、种群中的平均混交率和平均受精率与食物密度之间的关系具有较高的克隆多样性,食物密度、克隆以及两者间的交互作用对轮虫种群增长率、最大种群密度、平均混交率和平均受精率均有极显著性影响(P0.01).研究角突臂尾轮虫种群增长参数的克隆在所有的食物密度和克隆组合中,克隆2在2.0×10~6个细胞/m L食物密度下的种群增长率和最大种群密度均最高,克隆3在1.0×10~6个细胞/m L食物密度下平均混交率最高,克隆3和9在2.0×10~6个细胞/m L食物密度下的平均受精率最高.因此,在开展角突臂尾轮虫的规模化培养时,拟首选克隆2和2.0×10~6个细胞/m L的斜生栅藻密度;而欲开展角突臂尾轮虫休眠卵的批量生产,则拟选择克隆3和1.0×10~6个细胞/m L的斜生栅藻密度.     

深圳福田红树林区浮游藻类时空分布的研究

在2005年11月(秋)、2006年1月(冬)、2006年4月(春),分别对深圳福田红树林保护区5个水质监测站的浮游藻类进行采样研究.共鉴定到浮游藻类5门27属52种(含1变种和9未知种),密度在1.2×106～8.8×106个/L之间,平均密度为4.9×106个/L.硅藻门种类最多,有17属35种(含未知7种),占总种类数的67.3%,而且密度最大,高达8.7×106个/L;最少为隐藻门的种类,尚未发现甲藻门的种类.耐污染特征的种类如极微小环藻(Cyclotella caspia)、颤藻(Oscillatoria spp.)和小球藻(Chlorella vulgaris)是藻类群落的主要成分.各站分布的藻类群落组成季节差异明显,而种类数和密度并没有明显的季节变化.各站的优势种和优势类群存在时空差异.评价各站水质,反映出该红树林区水体处在中营养至富营养化状态.     

高位虾池水体细菌和弧菌的密度变化及影响因素

研究了位于广东湛江东海岛北寮村和庵里村的4个凡纳滨对虾(Penaeus vannamei)高位池养殖过程水体中的可培养异养细菌和弧菌的密度变化及其影响因素.结果表明:1)北寮村虾池BL1和BL2的可培养异养细菌密度变化均呈现中间高两头低、后期多于初期的单峰变化趋势;BL1的弧菌密度变化趋势和可培养异养细菌的变化趋势相似,而BL2则是前期稍微升高而后下降,后期又呈升高态势,峰值出现在养殖末期;水源地BL3的可培养异养细菌密度变化为初期平缓,后期明显多于初期,大体呈上升态势,而BL3弧菌密度变化趋势则比较平缓.2)庵里村发病的虾池AL1的可培养异养细菌和弧菌密度呈现出单峰变化趋势,在养殖中途爆发病害时,可培养异养细菌密度高出未发病的正常池2个数量级;庵里村虾池AL2的可培养异养细菌密度变化趋势也是中间高两头低,而弧菌的密度变化则是无规律的波动;水源地AL3的可培养异养细菌密度变化大体呈下降趋势,弧菌密度放养初期最高.3)高位虾池的可培养异养细菌和弧菌密度虽多于水源地,但差异不显著,同一个位点,细菌和弧菌密度呈现同步增多或减少.虾场水体的可培养异养细菌和弧菌密度与多数环境因子之间相关性不显著,这与虾池养殖生态系统受人为因素影响较大有关,同时反映了高位虾池生态系统受多种因子作用的复杂性.     

遵义市两种行道树树皮着生藻类物种多样性及其群落特征研究

2017年12月对遵义市主城区常见的二球悬铃木(Platanus acerifolia)和香樟(Cinnamomum camphora)等2种行道树树皮着生藻类进行采集、鉴定和统计分析。初步检出树皮着生藻类共18种,以蓝藻和绿藻种类为主。其中,二球悬铃木检出15种树皮着生藻类,种类组成表现为蓝藻>绿藻;香樟检出10种树皮着生藻类,种类组成表现为绿藻>蓝藻。2种行道树树皮着生藻类优势种均为颗粒粘球藻(Gloeocapsa granosa)和点形粘球藻(Gloeocapsa punctata)。树皮着生藻类平均密度为(1.05±0.17)×10~5 cells·cm~(-2);其中,在二球悬铃木和香樟树皮上分别为(0.94±0.10)×10~5 cells·cm~(-2)和(1.16±0.11)×10~5 cells·cm~(-2)。树皮着生藻类密度在不同树种之间和采样朝向之间均具有显著性差异(P<0.05)。二球悬铃木和香樟树皮着生藻类群落的Shannon-Weaver指数(H′)分别为1.13和1.33;向水侧和背水侧的H′分别为1.11和1.19。     

南昌市艾溪湖浮游藻类的多样性调查与评价

于2011年1、4、7月份对艾溪湖的浮游藻类进行取样调查.研究表明:艾溪湖水体中共发现藻类6门,40属;其中绿藻门种类最多,有19属;其次是蓝藻门和硅藻门分别为9属和8属.浮游藻类的细胞密度变化从62.45×106～395.52×106个/L,平均数量为209.76×106个/L;冬、春两季优势种类为绿藻门的栅藻属;夏天则为蓝藻门的平裂藻,占总藻类数的77.04;.多样性指数、物种丰富度、均匀度这3个指数值均表明水体已经严重污染.     

甘蔗渣悬浮颗粒和芽孢杆菌在凡纳滨对虾高位池养殖中的应用

向凡纳滨对虾高位池(面积均为0.067 m~2)养殖环境中添加甘蔗渣悬浮颗粒与芽孢杆菌,设置不同梯度放养量,分别放养6万与16万尾虾苗,各处理组为对照组6、蔗渣和菌组6,对照组16、蔗渣和菌组16,通过测定水质、细菌数量和对虾生长等指标,评估对养殖环境和对虾生长的影响,实验结果表明:各组生物絮团含量最大值分别为1.1 m L/L,1.0 m L/L,0.4m L/L,0.4 m L/L,都维持在较低水平,各养殖密度条件下添加蔗渣和菌组都大于相应对照组,这说明甘蔗渣悬浮颗粒和芽孢杆菌的添加,对水体中生物絮团的形成有一定的促进作用。各养殖密度下蔗渣和菌组水体中芽孢杆菌数量维持在10~4 cfu/m L左右,而对照组都则维持在10~2 cfu/m L左右,蔗渣和菌组分别大于相应对照组,而弧菌数量在实验后期要低于相应对照组,原因可能是甘蔗渣悬浮颗粒的添加,为芽孢杆菌提供了大量的附着基,有效增加了水体中芽孢杆菌数量,抑制了弧菌生长。收获时,蔗渣和菌组6对虾体重为9.09±0.43 g,对照组6为8.19±0.36 g,显著大于对照组(P0.05);蔗渣和菌组16(10.42±0.55g)也显著大于对照组16(8.33±0.51 g)(P0.05);蔗渣和菌组6的产量为325 kg,比对照组6高100 kg;蔗渣和菌16组最终产量为381 kg,比对照组16高276.5 kg。研究表明:甘蔗渣悬浮颗粒和芽孢杆菌的添加,能促进生物絮团的形成,增加和维持水体中芽孢杆菌等有益菌的数量,改善养殖环境,促进对虾生长,提高对虾产量和成活率。     

自来水中添加N,P后的浮游藻类生长试验

为了解水体营养物质低限浓度对浮游植物生长的影响,于2006年4月研究了浮游植物在自来水及添加不同浓度氮和磷后的自来水中生长情况.结果表明,在自来水中,浮游藻类仍然能够大量生长繁殖,培养28 d后个体密度可达8.00×104 inds·L-1.在添加总氮(TN)浓度分别为0.8,0.4,0.2,0.1,0.05和0.025 mg·L-1的自来水样中,浮游藻类浮游藻类密度分别达到1.69×105,2.81×105,1.19×105,1.03×105,5.88×104和8.12×104 inds·L-1.在添加总磷(TP)浓度分别为0.16,0.08,0.04,0.02,0.01和0.005 mg·L-1 的自来水样中,密度分别达到1.71×106,7.23×105,5.13×105,5.00×105,3.85×105和3.75×105 inds·L-1.藻类密度与添加的TN浓度之间关系为y=-88 650x2 895 456x 26 326,与TP浓度之间关系为y=8×106x 262 582.添加P对藻类生长的影响比N更为显著.控制水体氮磷浓度难以达到控制浮游植物大量繁殖的目的.     

鲢对富营养化水体的消减作用研究

以鲢为对象,通过设计室内试验,控制水体总磷(TP)和叶绿素a(Chl a)的初始浓度(0.355mg/L,57μg/L),改变总氮(TN)浓度(2.892mg/L和3.714mg/L浓度梯度),研究了鲢对设定富营养化水体的消减作用.结果表明,向100L实验水体中投入(10±1)g鲢(1尾)后,两种处理组水体中TP、TN和Chl a均降低,但初始TN浓度为3.714mg/L时鲢对富营养化水体的作用效果比TN浓度为2.892mg/L显著,表明鲢对富营养化水体的治理与TN浓度相关.     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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