3种常见有机磷农药对麦瑞加拉鲮鱼幼鱼的急性毒性

开展了三唑磷、乙酰甲胺磷、增效水胺硫磷对麦瑞加拉鲮鱼幼鱼的急性毒性试验,结果表明:三唑磷对麦瑞加拉鲮鱼幼鱼24h,48h,72h,96h的半致死浓度分别为0.080mg/L,0.065mg/L,0.060mg/L,0.050mg/L;乙酰甲胺磷对麦瑞加拉鲮鱼幼鱼24h,48h,72h,96h的半致死浓度分别为113.783mg/L,114.451mg/L,113.366mg/L,113.214mg/L;增效水胺硫磷对麦瑞加拉鲮鱼幼鱼24h,48h,72h,96h的半致死浓度分别为0.736mg/L,0.549mg/L,0.469mg/L,0.280mg/L。麦瑞加拉鲮鱼幼鱼对三唑磷、乙酰甲胺磷、增效水胺硫磷96h安全质量浓度分别为0.005mg/L、0.028mg/L和11.321mg/L,3种有机磷农药的毒性大小依次为三唑磷、乙酰甲胺磷、增效水胺硫磷。最后,还就三唑磷、乙酰甲胺磷、增效水胺硫磷对麦瑞加拉鲮鱼幼鱼的急性致毒效应特征以及麦瑞加拉鲮鱼幼鱼对三唑磷、乙酰甲胺磷、增效水胺硫磷的安全浓度进行了评价。     

3种有机磷农药对黑鲷幼鱼的急性毒性研究

以体长(5.09±0.71)cm、体重(2.09±0.66)g的黑鲷幼鱼为实验动物,采用静水停食实验法,在水温(28.8±1.6)℃条件下,开展了乙酰甲胺磷、辛硫磷、三唑磷对黑鲷幼鱼的急性毒性实验。结果表明,3种农药对黑鲷幼鱼均呈现以蓄积为主导的急性毒发效应,3种农药对黑鲷幼鱼的毒性大小依次为三唑磷、辛硫磷和乙酰甲胺磷,其中乙酰甲胺磷对黑鲷幼鱼24h,48h,72h,96h的半致死浓度分别为30.11mg/L,21.83mg/L,17.30mg/L,14.07mg/L;辛硫磷对黑鲷幼鱼24h,48h,72h,96h的半致死浓度分别为0.50mg/L,0.49mg/L,0.34mg/L,0.30mg/L;三唑磷对黑鲷幼鱼24h,48h,72h,96h的半致死浓度分别为0.068mg/L,0.060mg/L,0.054mg/L,0.051mg/L。最后,还就黑鲷幼鱼对乙酰甲胺磷、辛硫磷、三唑磷的急性致毒效应特征、药物间的致毒效果及其安全浓度进行了评价。     

4种常用消毒剂对泥螺和彩虹明樱蛤的急性毒性

基于潮间带滩涂潮汐特征,确定12 h为总实验时间,采取全程不换药和6 h换药两种染毒方式,于2006年7～8月在浙江省岱山县岱西镇开展了溴氯海因、强杀118、碘溴海因和二溴海因对泥螺和彩虹明樱蛤的急性毒性实验.结果表明:各实验药物对泥螺、彩虹明樱蛤的致毒效应均随实验时间延长而缓慢增强;全程不换药组的半致死质量浓度LC50值均高于换药组,经u检验发现,两者致毒效果无差异;泥螺对消毒剂的耐毒能力略强于彩虹明樱蛤,4种消毒剂中以溴氯海因毒性最小,二溴海因最大,溴氯海因、强杀118、二溴海因及碘溴海因对泥螺和彩虹明樱蛤安全质量浓度分别为0.330,0.088,0.040,0.051 g/L和0.250,0.140,0.079,0.150 g/L.最后,就泥螺和彩虹明樱蛤对溴氯海因、强杀118、二溴海因、碘溴海因的急性致毒效应特征、药物间的致毒效果及其安全质量浓度进行了探讨.     

三唑磷和乙酰甲胺磷对海洋桡足类的急性毒性研究

研究了三唑磷和乙酰甲胺磷两种常用有机磷农药对婆罗异剑水蚤和日本虎斑猛水蚤的急性毒性,报道了相关的24hLC50和48hLC50数据.其中三唑磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为6.844μg/L和16.26μg/L,而乙酰甲胺磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为216.3 mg/L和76.54 mg/L.结果表明:对两种桡足类而言,三唑磷的毒性大于乙酰甲胺磷;桡足类对有机磷农药的耐受性具有种的特异性.据此提出使用农药的相关建议,指出应该严格控制三唑磷的使用,为近岸海区环境的质量评价和污染防治提供参考依据,并为监测有机磷农药污染环境提供了参考资料.     

菲对泥鳅幼体的急性毒性效应

为研究菲对水生生物的毒性效应,以泥鳅(Misgurnus anguillicaudatus)幼体为研究对象,采用静水实验法来研究菲对泥鳅幼体的急性毒性效应。以等对数间距法设置5个不同浓度(14.69mg/L、21.58 mg/L、31.62 mg/L、46.77 mg/L、68.39 mg/L)的菲溶液,观察泥鳅幼体暴露在不同浓度菲中24 h、48 h、72 h、96 h的急性毒性效应。结果表明,菲对泥鳅幼体毒性随染毒时间的延长和菲浓度的增大而增强,泥鳅幼体24 h、48 h、72 h、96 h半致死浓度(LC50)分别为58.57 mg/L、33.34mg/L、17.58 mg/L、14.45 mg/L,安全浓度(SC)为3.25 mg/L。     

氨氮和亚硝态氮对大黄鱼幼鱼的急性毒性效应

在水温(23±1)℃,盐度20,pH值7.4~7.5,溶解氧大于5.0 mg/L的条件下研究了氨氮和亚硝态氮对体质量为(31.54±0.99)g的大黄鱼幼鱼的急性毒性效应.试验结果表明,氨氮对大黄鱼幼鱼的24、48、72和96 h的半致死浓度LC50及安全浓度SC分别为37.34、20.97、17.59、12.45及1.25 mg/L,对应的非离子氨的半致死浓度LC50及安全浓度SC分别为0.46、0.25、0.21、0.15及0.015 mg/L,亚硝态氮对大黄鱼幼鱼的24、48、72和96 h的半致死浓度LC50及安全浓度SC分别为137.45、94.02、72.81、50.06及5.01 mg/L.     

乙酰甲胺磷对尾草履虫和绿草履虫的急性毒性作用

以两种草履虫作为受试生物,比较研究了乙酰甲胺磷胁迫下的急性毒性作用.随着药物浓度增高,乙酰甲胺磷对两种草履虫的毒性增大,且呈明显的剂量效应关系;试验测定尾草履虫和绿草履虫1 h和12 h半致死浓度LC50分别为:11.972,3.191 1,10.928和2.901 1 mg/L,其中LC50 95%的可信限分别为:10.894～13.113 mg/L,2.895 7～3.512 1 mg/L,9.905 5～13.113 mg/L 和2.646 5～3.163 9 mg/L.回归分析了死亡概率单位与浓度对数之间存在着线性关系.草履虫可以成为乙酰甲胺磷敏感的毒性评价生物,绿草履虫作为环境污染的安全评价生物其敏感度更高.     

氧化乐果胁迫对泥鳅的急性毒性作用研究

为了研究氧化乐果对水生动物的毒性作用,采用96 h静水试验法检测泥鳅在不同浓度(24.67、30.41、37.50、46.24、57.02 mg/L)氧化乐果中暴露24、48、72、96 h时的急性毒性作用,结果表明:氧化乐果对泥鳅的毒性作用是随暴露时间的延长和浓度的增大而增强,对泥鳅24、48、72、96 h半致死浓度(LC_(50))分别为76.91、51.17、46.03、35.89 mg/L,安全浓度(SC)为6.8 mg/L,属于高毒等级的水体污染物。     

两种有机磷农药对沼水蛙蝌蚪抗氧化系统及MDA浓度的影响

研究了两种有机磷农药三唑磷和乙酰甲胺磷对沼水蛙蝌蚪超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及脂质过氧化产物丙二醛(MDA)浓度的影响.结果表明:在不同质量浓度(0.2,0.4,1.2,2.0,2.8 mg/L)的三唑磷染毒后,蝌蚪的SOD活性开始被激活,48 h或72 h后活性逐渐达到最高值;随着染毒时间的延长,其活性则被抑制而降低;CAT活性和MDA浓度都随着三唑磷质量浓度的增加和处理时间的延长出现极显著的提高,且MDA浓度与三唑磷质量浓度呈现显著的剂量效应关系.在不同质量浓度(15.0,22.5,30.0,37.5,45.0 mg/L)的乙酰甲胺磷染毒后,蝌蚪的SOD活性在较短的时间(24 h)内出现最高值,随后降低至与对照组相当的水平;随着染毒时间的延长,CAT活性逐渐被抑制而呈减低的趋势,而MDA浓度明显呈现出由低到高的变化过程.两种农药都会不同程度改变沼水蛙蝌蚪抗氧化防御系统,造成毒害作用.     

重铬酸钾对斑马鱼的急性毒性及组织过氧化氢酶活性的影响

为研究Cr6+单一毒性对斑马鱼的毒性安全评价,选择重铬酸钾进行急性毒性试验,观察斑马鱼在染毒3~96h的症状,以半数致死浓度(LC50)判断重铬酸钾对斑马鱼的毒性作用。结果表明,24h、48h、72h、96h的LC50分别为426.5795mg/L、141.2538mg/L、138.0384mg/L、128.8250mg/L,经鱼类急性毒性分级表判断重铬酸钾为低等毒。同时研究了不同浓度Cr6+对斑马鱼组织过氧化氢酶(CAT)活性的影响,发现鱼肝和肌肉中的CAT活性随着浓度的增加呈抛物线。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.