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1.
本实验以叔碳酸13-煤油溶液为萃取剂,萃取稀土元素镨(Ⅲ),研究了该体系的萃取平衡.在Pr~(3+)离子浓度为0.00187~0.0200mol/ι,叔碳酸浓度(以R_2H_2计算)为0.100~1.00mol/ι,温度为20(±1)℃时,确定了有机相中萃合物的组成是PrR_3·4RH,以单分子形式存在.在实验条件下,萃取体系的化学反应方程式为:(Pr~(3+))a+7/2(R_3H_2)_0 (PrP_3·4RH)_0 +3(H~+)a其表观萃取平衡常数K=1.35×10(-13).  相似文献   

2.
本文研究1-苯基-3-甲基-4-苯甲酰基吡唑啉酮-5(PMBP)与丁基膦酸二丁酯(DBBP)或磷酸三丁酯(TBP)的氯苯溶液在硝酸介质中对Eu(Ⅲ)的协同萃取。测得了萃合物的组成为EuA_3·HA、EuA_3·2DBBP或EuA_3·2TBP。在18℃时的萃取平衡常数分别为: Eu~(3 )(<10~(-5)M)/HNO_3,NaNO_3/(μ=0.1)/PMBP-C_6H_5Cl体系 K_3=[EuA_3·HA]_0[H~ ]~3/[Eu~(3 )][HA]_0~4=1.51×10~(-3) Eu~(3 )(<10~(-5)M)/HNO_3,NaNO_3(μ=0.1)/PMBP—DBBP—C_6H_5Cl体系 K_(s·e)=[EuA_3·2DBBP]_0[H~ ]~3/[Eu~(3 )][HA]_0~3[B]_0~2=2.40×10~2 Eu~(3 )(<10~(-5)M)/HNO_3,NaNO_3(μ=0.1)/PMBP-TBP-C_6H_5Cl体系 K_(s·e)=[EuA_3·2TBP]_0[H~ ]/[Eu~(3 )[HA]_0~3[B]_0~2=1.74×10~1 讨论了萃合物的结构及协同萃取的机理。  相似文献   

3.
本文报导了高氯酸二水·双(N-氧化吡啶-2-甲醛)缩-1,3-丙二胺合镍的合成,粉末衍射数据及精化的单胞参数.主要的结晶学数据为:[Ni(C_(15)H_(16)N_4O_2)(H_2O)_2)(ClO_4)_2.正交晶系,空间群Pnam 或Pna2_1,a=7.490(4)×10~(-10)m,b=15.510(11)×10~(-10)m,c=18.457(13)×10~(-10)m,Z=4,Dcal=1.790,Dobs=1.765,品质因子为15.7.  相似文献   

4.
本文研究了酚藏花红阳离子与氯锑酸络阴离子在酸性介质中形成红色离子缔合物的条件,从而建立了萃取比色测定微量锑的新方法。实验表明,此缔合物可被混合溶剂(环己烷+丁酮)萃取,其表观摩尔吸光系数ε_(λ532)=5.8×10~4升·摩尔~(-1)·厘米~(-1)·sb 含量在0—25μg/10ml 之间遵守比尔定律。  相似文献   

5.
在较高的钇离子浓度下,应用“循环法”,改进了A.W.Fletcher 的数据处理方法,研究了Versatic 10萃取钇的平衡。在温度为25±1℃下,有机相由Versatic 10和正己烷组成,水相由YCl_2和HCl 组成,水相中加入NaCl 维持离子强度为1.实验确定萃合物的组成为YA_3·3HA,表观萃取平衡常数为2.8×10~(-14)~9.5×10~(-14).萃取反应式表示如下:Y_(α)~(3+)+6H_2A_(2(o))(?)YA_3·3HA_(o)+3H~+_(α)  相似文献   

6.
H.W.B.Roozeboom用溶解度法确定了下列几种硫酸钍水合物的存在:Th(SO_4)_2·9H_2O,Th(SO_4))_2·8H_2O,Th(SO_4)_2·6H_2O,Th(SO_4)_2·4H_2O和Th(SO_4)_2·2H_2O。E.L(?)wenstein于常温下,用使9水合硫酸钍在各种浓度的硫酸溶液上长时  相似文献   

7.
模拟试验的数学模型是六阶非线性振动型微分方程,其等价形式为: dx╱dt=A_1x+g_1(t,x) (1) 本文证明了以下定理: 定理1.方程(1)属于“D类系统”,因而一切解均匀最终有界。定理2.方程(1)至少存在一个调和解。定理3.若方程(1)有多于一个的调和解,则其参数应满足: [(-B~3)╱(8(1+ε)~3)]~2+[1╱(54bβ)((27bβB~2)╱(1+ε)~2+24αβ-(8(1+ε)))]~3≤0 (2) 定理4.设方程(1)满足下列三个条件①不等式(2)成立; ②求得n_1个m阶Galerkin逼近~(j)(t),相应误差η_1~(j)(t)适合‖η_1~(j)(t)‖≤r_2~(j),j=1,2,……n_1; ③存在正数r~(j)使得(1)的典则化方程在S_j:‖y-φ~(j)‖≤r~(j)中的局部Lipschitz常数Lr~(j)以及r~(j),r_2~(j)满足(1+max|λi+k|)/(min|λi+k|)·(3r_2~(j))/(δ≤σ((σ-KLr~(j)))/(K~2Lr~(j)))r~(j)i=1,2,3,4, j=1,2,……n_1且S_i∩S_h=0 i≠h;则方程(1)至少存在n_1个调和解,它们分别出现在m阶Galerkin逼近~(j)(t)的附近。  相似文献   

8.
羧基桥联的双核Cu(Ⅱ)配合物的合成及性质初步研究   总被引:1,自引:0,他引:1  
合成了二个新的一个分子中含有二个羧基桥联的双核 Cu(Ⅱ)配合物[Cu(Phen)(HCOO)]_2·(NO_3)_2·3H_2O(1),[Cu(Phen)(CH_3COO)]_2·(NO_3)_2·3H_2O(2)和一个一分子中含有一个羧基桥和一个羟基桥的双核 Cu(Ⅱ)配合物[Cu_2(OH)(C_2H_5COO)(Phen)_2]·(NO_3)_2·H_2O(3)以及单核 Cu(Ⅱ)配合物[Cu(Phen)(CF_3COO)]·(NO_3)·H_2O(4)(其中 Phen 为2,9-=甲基-1,10-啡罗啉).通过元素分析,等离子光谱、红外光谱,TG 及 X-射线粉末衍射分析对四个配合物进行了初步表征,测定了它们的氧化还原电位及电导.通过分析讨论,确定了配合物中羧基的配位方式.  相似文献   

9.
用1,4—二(2′—甲酰基苯基)—1,4-二氧杂丁烷和1,7—二(2′—甲酰基苯基)—1,4,7—三氧杂庚烷,在相转移催化剂存在下,用 KMnO_4氧化,制得了两种键端为羧酸的开链聚醚配体:2,2′—(1,4—亚乙二氧基)—二苯甲酸(H_2L~1)和2,2′—(1,7—二乙醚二氧基)—二苯甲酸(H_2L~2)。用元素分析,红外光谱对它们进行了表征。在甲醇或水介质中,制得了 H_2L~1和 H_2L~2的镧系元素固体配合物,通式分别为 LnL~1(NO_2)·nH_2O 和 Ln_2L(_3~2)·nH_2O(Ln=La—Lu,Pm 除外);在甲醇介质中还制得了它们的 UO(_2~(2+))和 Th~(4+)配合物,UO_2L~1·6H_2O,UO_2L~2·3H_2O,ThL(~1_2)·H_2O 和 ThL(~2_2)·5H_2O。  相似文献   

10.
本文建立了应用藏红T作显色剂分光光度法测定微量金的新方法。金(Ⅲ)在硫酸介质中及溴化钠存在下与藏红T反应形成红色络合物。此络合物易被非水溶剂如:环己烷+丁酮(3+2)、苯+丁酮(7+8)环己烷+MIBK(3+2)、乙酸异戊酯、乙酸丁酯或乙酸正戊酯所萃取,最大吸收在528—530nm之间(表观摩尔吸光系数e=5.70×10~4—7.25 x10~4l·mol~(-1)·cm~(-1))。分别在0—22、5、0—30、0—30、0—35、0一35、0一30微克金/10毫升遵守比尔定律。本法已应用于矿石中微量金的分析。  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
20.
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   

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