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1.
以体长(5.56±0.31)cm、体质量(2.67±0.40)g的麦瑞加拉鲮鱼幼鱼为试验动物,采用静水试验法,在水温28.1±0.6℃条件下,开展了氟虫腈、乐果对麦瑞加拉鲮鱼幼鱼的急性毒性研究。结果表明:氟虫腈对麦瑞加拉鲮鱼幼鱼24h、48h、72h、96h的半致死浓度分别为0.020mg/L(95%置信限[0.009,0.066])、0.017mg/L(95%置信限[0.007,0.064])、0.010mg/L(95%置信限[0.004,0.041])、0.004mg/L(95%置信限[0.002,0.017]);乐果对麦瑞加拉鲮鱼幼鱼24h、48h、72h、96h的半致死浓度分别为315.500mg/L(95%置信限[150.453,372.135])、142.233mg/L(95%置信限[64.565,190.985])、62.517mg/L(95%置信限[25.136,102.825])、28.708mg/L(95%置信限[12.759,46.174])。麦瑞加拉鲮鱼幼鱼对氟虫腈、乐果的96h安全质量浓度分别为0.0004mg/L、2.8708mg/L,2种农药的毒性大小为氟虫腈、乐果。最后,还就氟虫腈、乐果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氟虫腈、乐果的安全浓度进行了评价。  相似文献   

2.
3种常见有机磷农药对麦瑞加拉鲮鱼幼鱼的急性毒性   总被引:1,自引:3,他引:1  
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。  相似文献   

3.
3种有机磷农药对黑鲷幼鱼的急性毒性研究   总被引:1,自引:1,他引:0  
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。  相似文献   

4.
3种常见农药对泥螺、彩虹明樱蛤的急性毒性   总被引:2,自引:1,他引:2  
开展了狂杀宝、乙酰甲胺磷、三唑磷等3种常见农药对泥螺和彩虹明樱蛤的急性毒性试验。结果表明:3种常见农药对泥螺、彩虹明樱蛤的急性毒性强度由大到小均依次为三唑磷、狂杀宝和乙酰甲胺磷,其中狂杀宝对彩虹明樱蛤、泥螺24 h,48 h,72 h,96 h的半致死浓度分别为3.412 mg/L,2.670 mg/L,2.469mg/L,2.168 mg/L和3.159 mg/L,2.527 mg/L,1.341mg/L,1.028 mg/L;乙酰甲胺磷对彩虹明樱蛤、泥螺24 h,48 h,72 h,96 h的半致死浓度分别为219.409 mg/L,202.143 mg/L,107.273 mg/L,88.559 mg/L和39.054 mg/L,35.590 mg/L,33.64 mg/L,26.539 mg/L;三唑磷对彩虹明樱蛤、泥螺24 h,48 h,72 h,96 h的半致死浓度分别为2.018 mg/L,1.185 mg/L,1.127 mg/L,1.049 mg/L和0.935 mg/L,0.876 mg/L,0.568 mg/L,0.368 mg/L。狂杀宝、乙酰甲胺磷、三唑磷对泥螺和彩虹明樱蛤的安全质量浓度分别为0.102 8 mg/L,2.653 9 mg/L,0.036 8 mg/L和0.2168 mg/L,8.855 9 mg/L,0.104 9 mg/L。最后,就泥螺和彩虹明樱蛤对狂杀宝、乙酰甲胺磷、三唑磷的急性致毒效应特征、药物间的致毒效果比较及其安全浓度进行了评价。  相似文献   

5.
为了明确氟虫腈对鸟类的短期饲喂毒性效应。以准则推荐物种日本鹌鹑为试验对象,采用饲料拌药法对日本鹌鹑进行短期饲喂毒性测试,获取半致死浓度并评价其毒性等级。结果显示:95%氟虫腈原药对日本鹌鹑的短期饲喂毒性8 d的半致死浓度LC50为367.6 mg a.i./kg饲料,95%置信限为343.5~394.4 mg a.i./kg饲料,毒性等级为“高毒”。结果表明:95%氟虫腈原药与饲料混拌被鸟类取食后,对鸟类会产生较高的毒性,因此在田间施用该农药时要注意对环境鸟类的保护。  相似文献   

6.
目的:为了明确12种常用农药对茴香薄翅野螟幼虫的毒力.方法:采用胃毒法,室内测定各农药的致死浓度.结果:各农药处理24h后,毒死蜱、阿维菌素、高效氯氰菊酯、多杀菌素、氯虫苯甲酰胺、乙酰甲胺磷、三唑磷、杀虫单、杀螟丹、溴虫腈、茚虫威、丁醚脲对茴香薄翅野螟幼虫的LC_(50)值分别为4.1278mg/L、5.1388mg/L、5.9060mg/L、5.2977mg/L、6.5671mg/L、8.8636mg/L、10.2747mg/L、14.5448mg/L、11.5089mg/L、8.5582mg/L、5.8473mg/L、55.8615mg/L;上述各农药处理48h后的LC_(50)值分别为,2.5759mg/L、0.7514mg/L、0.9522mg/L、1.4031mg/L、0.4814mg/L、5.7853mg/L、8.3911mg/L、9.7326mg/L、6.0748mg/L、4.0121mg/L、6.1810mg/L、26.5905mg/L.结论:其中用多杀菌素、阿维菌素、氯虫苯甲酰胺和高效氯氰菊酯处理茴香薄翅野螟后的LC_(50)相对较小,说明这几种药在生产中防治该虫时值得推广.  相似文献   

7.
锌对鲫鱼的急性毒性及安全浓度评价   总被引:1,自引:0,他引:1  
胡超 《孝感学院学报》2008,(Z1):113-115
以鲫鱼为受试生物,采用静水法生物测试,以致死率为指标研究了重金属锌对鲫鱼的急性毒性。所得24h、48h、72h和96h的半致死浓度为40.631 mg/L,39.234 mg/L,38.449 mg/L,37.406 mg/L,安全质量浓度为3.7406 mg/L。试验结果表明:鲫鱼对重金属锌的耐受性较高。锌对鲫鱼为低毒物质,其安全浓度远高于标准。LC50与时间的关系密切,随着时间的推移,LC50逐渐变小。同时,还表明锌的致毒过程较快,鲫鱼在48h内即出现大量死亡。  相似文献   

8.
仅采用共毒系数法对复配剂的最佳配比进行筛选,可能造成真正最佳配比的漏筛.以柑桔潜叶蛾(Phyllocnistis citrella Stainton)幼虫和稻纵卷叶螟(Cnaphalocrocis medinalis Guenée)3龄幼虫为试虫,分别测定40%毒死蜱EC、4.5%高效氯氰菊酯EC、1%氟虫腈EC、20%三唑磷EC单剂和50.25%毒死蜱·高效氯氰菊酯EC和31%氟虫腈·三唑磷复配剂的毒力,并计算共毒系数Y.将高效氯氰菊酯和氟虫腈在复配剂有效成分中的质量分数k进行反正弦转换(X=arcsin(k)1/2),通过SPSS软件拟合得k反正弦转换值与共毒系数的数学模型依次为Y1=109.884 1.743X1-0.012X21,Y2=195.804 4.153X2-0.044X22.对上述的2个方程进行求导可得Y'1=1.743-0.024X1和Y'2=4.153-0.088X2.令Y'=0,则有X1=72.250和X2=47.193,将X1=72.250和X2=47.193代入原方程,求得最大CTC分别为172.525和293.801.将X1=72.250和X2=47.193代入X=arcsin(K)1/2中可以求得高效氯氰菊酯在毒·高氯复配剂有效成分中的质量分数K值为0.907,氟虫腈在氟·三复配剂有效成分中的质量分数K为0.538.将K值转换为两单剂的配比可得毒死蜱∶高效氯氰菊酯最佳配比大约为10∶1,氟虫腈三唑磷最佳配比大约为1.2∶1.  相似文献   

9.
运用毒理学实验方法,研究双酚A(BPA)和邻苯二甲酸二甲酯(DMP)对发头裸腹溞的急性致毒效应.结果显示:双酚A对发头裸腹溞24、48、72、96 h的半数致死浓度分别为14.129、11.094、9.116、6.815 mg/L;邻苯二甲酸二甲酯对发头裸腹溞24、48、72、96 h的半数致死浓度分别为63.460、15.065、4.272、0.865 mg/L.BPA和DMP对发头裸腹溞的安全浓度分别为0.682 mg/L和0.087 mg/L,其死亡率和上述两种雌激素质量浓度间存在着明显的正相关性,且随着染毒时间的延长半数致死浓度逐渐降低,发头裸腹溞对DMP的敏感性高于BPA.根据化学物质对溞类的毒性评价标准,双酚A和邻苯二甲酸二甲酯分别为中毒和高毒物质.  相似文献   

10.
二种有机磷农药对褶皱臂尾轮虫的急性毒性   总被引:2,自引:0,他引:2  
谢钦铭  赵美珠 《江西科学》2006,24(5):297-300
本文研究了二种有机磷农药敌百虫和久效磷对褶皱臂尾轮虫(Brachionus plicatilis)的急性毒性和对褶皱臂尾轮虫孵化率的影响。试验结果表明:褶皱臂尾轮虫的孵化率随着有机磷农药浓度的增加而降低,孵化时间随之增加,敌百虫和久效磷对褶皱臂尾轮虫的48 h半致死浓度(LC50)分别是2.876 7 mg/L和0.0534mg/L。  相似文献   

11.
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.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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。  相似文献   

14.
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  相似文献   

15.
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  相似文献   

16.
17.
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.  相似文献   

18.
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).  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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