首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 192 毫秒
1.
报导了整合配体N,N,N‘,N’-四(2‘-苯并咪唑甲基)乙二胺(EDTB)-钴(Ⅱ)配合物的合成和红外(IR)、紫外-可见(UV-Vis)光谱、电子自旋共振(ESR)谱表征,据元素分析、摩尔电导和上述光谱数据,与已报导的EDTB含铜(Ⅱ)、锰(0282)配合物X-射线单晶结构比较,推测双核钴(Ⅱ)配合物Co2(EDTB)Cl4.0.5C2H5OH.4.H2O的Co(Ⅱ)离子处于四方锥,而单核钴(  相似文献   

2.
报道了对称的八齿(N6O2型)双核配体N,N,N′,N′-四(2′-苯并咪唑甲基)-1,4-二乙氨基乙二醚(EGTB)及两种含锰(Ⅱ)双核配合物:(Mn2EGTB(OAc)2)(BPh2).3H2O(I),(Mn2EGTB(OAc)Cl)Cl2.2CH3OH.H2O(Ⅱ),对(I),(Ⅱ)进行了^1HNMR,UV-Vis,摩尔电导,中远红外,EST和循环伏安研究,初步推测配合物(I)和(Ⅱ)分别具  相似文献   

3.
报道了对称六齿配体N,N,N’-四(2’-苯并咪唑甲基)乙二胺(EDTB)的两种含镍(Ⅱ)配合物「i(EDTB)」(ClO4)2.3H2O和「Ni(EDTB)」Cl2.2H2O.3C2H5OH的合成、表征及其对尿素水解的影响。根据配合物元素分析、摩尔电导、紫外-可见(UV-Vis)、红外(IR)、ESR谱和循环伏安(CV)等性质与已测X-射线单晶结构的同种配体含铜(Ⅱ)单核配合物比较,推测此两种配  相似文献   

4.
使用合成的钡镁锰矿(TODOROKITE)、碱硬锰矿(HOLLANDITE)型的MnO2及电解MnO2修饰碳膏电极,报告了它们在+1.0V ̄-1.0V电压范围和0.1M KCl溶液中的循环伏安图。Todorokite和hollandite的循环伏安图相似,都没有显明的电流峰。而电解MnO2的循环伏安图中,有两个阳极峰(+0.1V,+0.5VvsSCE)两个阴极峰(0.0V,-0.15V vs SX  相似文献   

5.
COHERENTOSCILLATORYWAVESFORMULTIDIMENSIONALHYPERBOLICSYSTEMSChenMing1)QiuQingjiu2)(1)DepartmentofRadioEngineering,SoutheastU...  相似文献   

6.
合成了过氧磷钨杂多酸盐α2-K7-mHm(P2W17(TαO2)O61).xH2O(M=K,TMA,TEA,TBA)并且极谱-循环伏安,IR,UV吸收光谱,XPS,XRD,^31PNMR,^183WNMR谱进行表征。  相似文献   

7.
部分取代苯定量结构-生物降解相关性(QSBR)研究   总被引:1,自引:0,他引:1  
采用Chems3D中量子化学MOPAC-AM1法计算了7种间苯胺类和8地苯酚的分子量高占有轨道能EHOMO、分子最低空轨道能ELUMO。用QSAR程序软件包查得分子体积Vm。结合分子连接性指数(^3X,^3X^v)对生物降解二级速率常数对数lgKb进行定量结构-生物降解相关性(QSBR)分析,通过回归分析,得到如下两个回归方程:lgKb=-0.832-0.118Vm+1.748^3X^v,n=15,R^2=0.832,SE=0.577,F=29.7,p=0.000。(1)lgKb=0.124Vm+1.749^3X^v,n=15,R^2=0.998,SE=0.5591,F=4148.99,p=0.000.(2)  相似文献   

8.
含苯并咪唑八齿配体EGTB双核钴(Ⅱ)配合物的合成?…   总被引:1,自引:1,他引:0  
报导了八齿配体N,N,N′,N′-四(2-苯并咪唑甲基)-1,4-二乙氨基乙二醚(EGTB)的4种双核钴(Ⅱ)配合物的合成及其红外(IR),紫外-可见(UV-Vis)光谱和电子自旋共振(ESR)谱表征,并用硝基蓝四氮唑(NBT)光照还原法证明这4种配合物均具有超氧化物歧化酶性质,与O2反应的速率常数在10^6~10^7mol^1.L.s^-1之间。  相似文献   

9.
THEOPTICALOBSERVATIONOFTHECOLLISTIONSOFCOMETSHOEMAKER-LEVY9WITHJUPITER¥ZhouHongnan(DepartmentofAstronomy,NanjingUniversity,21...  相似文献   

10.
本文论述循环伏安法(CV)中铂(Pt)对乙醇(EtOH)的定量吸附特性,及其对葡萄酒中EtOH测定的应用问题。用自制的Pt梳状工作电极。在0.1M的NaOH溶液中,EtOH的氧化峰电位为-240mV(相对Ag/AgCl参比电极)。以3σ背景值计,检出限为0.023%(V/V)。样品分析结果准确度为95.2-104.7%重现性范围2.8-3.1%RSD(n=8)。校准曲线的线性动态范围0.1-8%(  相似文献   

11.
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.  相似文献   

12.
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   

13.
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。  相似文献   

14.
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.  相似文献   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
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-  相似文献   

18.
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-  相似文献   

19.
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  相似文献   

20.
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  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号