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1.
目的研究含氮、氧三齿配体的配位性能和金属配合物结构,合成三齿配体吡啶二甲酸与铜(II)和水的配合物{[Cu(pydca)(H2O)]3}(pydcaH2 吡啶二甲酸). 方法采用X射线衍射法对配合物进行了晶体结构的测定. 结果结构简式C21H21Cu3N3O18,相对分子质量Mr=794.03, 三斜晶系,空间群为P1, 晶胞参数a=4.7200(10)AAU(1AAU=10-10m),b=10.355(4)AAU,c=26.837(11)AAU;α=98.190(7)°,β=93.290(5)°,γ=94.250(10)°,Z=2,V=1291.7(8)AAU3,F(000)=798,Dc=2.042 mg/m3, μ=2.545 mm-1.结果晶体分子中含3个类似结构的配合物单元. 结论每单元中心都以CuNO4五配位方式形成扭曲的四方锥构型.  相似文献   

2.
通过对量测数据新息的统计数学特性的分析,借助于主成分分析法的思想,根据矩阵的最大特征值反映矩阵的主要信息这一特点,提出了一种检测量测数据中是否含有野值的判别方法.此基础上,修正了Kalman滤波器的状态估计算法.使该算法在出现连续型野值时,能明显地降低误差,提高滤波精度.仿真结果证明了该方法的有效性.  相似文献   

3.
通过X射线单晶衍射测试了配合物Eu(NO3)3(phen)2的晶体结构(phen=1,10 -邻菲NB035罗啉).该配合物以单核分子形式存在,中心离子Eu(Ⅲ)分别与硝酸根上的氧原子和1,10 -邻菲NB035罗啉上的氮原子以双齿螯合方式配位,配位数为10.荧光光谱表明该配合物有Eu(Ⅲ)的特征发射光谱,其中5D0→7F2(615nm)跃迁发射强度最高.该配合物具有良好的热稳定性.  相似文献   

4.
为寻找具有生理活性的Troponoids,选择3-乙酰基NFDA1酚酮1和2-乙酰基-7-甲胺基NFDA1酮6与3,4,5-三甲氧基苯甲醛等取代醛反应得到缩合产物2~5,7~9;缩合产物3-(3,4,5-三甲氧基)肉桂酰基NFDA1酚酮2和3-(3,4-亚甲二氧基)肉桂酰基NFDA1酚酮4与羟氨和苯肼进行缩合成环得到苯乙烯基取代的缩杂环NFDA1酮化合物10~13;化合物1与3,4,5-三甲氧基苯甲醛在原甲酸三乙酯和高氯酸存在下反应一步得到2-(3,4,5-三甲氧基)苯基-4,9-二氢环庚并吡喃-4,9-二酮14。以上化合物2~5,7~14的结构经光谱分析和元素分析予以证实。  相似文献   

5.
SiO2体系的分子动力学研究   总被引:2,自引:2,他引:0       下载免费PDF全文
基于多体项展式理论方法导出的SiO2分子基态(~X1Α1 )的分析势能函数,用准经典的 Monte-Carlo轨线法对Si (3Pg) + OO′ (~X3Σ -g) 和O (1Dg) + SiO′(~X1Σ + )体系的分子反应动力学过程进行了计算.结果表明Si (3Pg) + OO′ (~X3Σ-g)体系生成络合物是一个阈能比较小的反应,而生成离解产物则是一个有比较大的阈能反应,其阈能值约为200 kJ·mol-1, 说明主要以生成络合物为主;O (1Dg) + SiO′ (AX~U1Σ + )体系没有络合物生成,生成离解产物O (1Dg)+ SiO′ (AX~U1Σ + )→O + O′ + Si的反应截面比非反应碰撞产物O (1Dg) + SiO′ (AX~U1Σ + )→Si + OO′的反应截面要大约两个数量级,在低能区是有阈能的反应,其阈能值约为120 kJ·mol-1.  相似文献   

6.
针对传感器量测数据丢失的卡尔曼(Kalman)滤波问题进行了研究,提出了一种基于虚观测值的鲁棒卡尔曼滤波算法,针对伯努利(Bernoulli)分布描述的量测数据丢失的模型,充分利用当前时刻的先验信息,应用趋势移动平均法来预估构造丢失数据时刻的虚观测值,建立了等效的传感器量测模型.利用鲁棒卡尔曼滤波方法来消除预测偏差较大的虚观测值对目标跟踪的影响,从而达到对目标的稳健跟踪.仿真实例说明了该算法能在量测数据丢失的情况下对目标进行有效的跟踪,跟踪精度高于跳变线性系统的卡尔曼滤波算法.  相似文献   

7.
紫杉醇生物合成途径及其相关酶的研究进展   总被引:1,自引:0,他引:1  
紫杉醇的生物合成过程已基本阐明,其合成以NB028牛儿基NB028牛儿基二磷酸为前体约需20步酶促反应,近一半的相关酶基因已得到克隆与表达.综述了紫杉醇生物合成及生物合成途径中9个酶基因的克隆和表达方面的研究进展,并指出随着紫杉醇生物合成分子生物学研究的不断深入,利用分子生物技术大规模生产紫杉醇将为期不远.  相似文献   

8.
以USB总线为基础,运用自动量程切换、光电隔离、TRMS/DC、自行校准等技术,设计小型化、模块化、通用化数字多用表.该表具有较高精确度和稳定性,51/2位数字显示,能够完成对直流电压、直流电流、交流电压、交流电流、2/4线电阻等项目的测量,并可以作为自动测试系统的数字多用表模块使用.  相似文献   

9.
作者给出了解NavierStokes方程的非协调混合四边形有限元(P~1-Q0和P~1-Q1,其中P~1表示P1非协调四边形元)的稳定化方法.P~1-Q0和P~1-Q1不满足inf-sup条件,因而所给的稳定化方法绕开了inf-sup条件对P~1-Q0和P~1-Q1元的限制.作者证明了该方法的稳定性和解的存在唯一性,并得到了最优误差估计.  相似文献   

10.
基于新息特性抗野值Kalman预测算法   总被引:1,自引:0,他引:1  
针对Kalman最优预测方法应用过程中,量测值中的野值对状态预测的不利影响,提出了一种基于新息正交特性实时估计量测方差的新算法.该算法使得修正的量测方差能够保持修正前的新息正交性,从而改变Kalman最优增益,修正状态预测值,使得预测误差的方差为最小.仿真结果表明,该算法能够克服野值对状态最优预测值的不利影响,提高了跟踪精度.  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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