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1.
采用水热方法合成了1种Pr(Ⅲ)配合物,[Pr(2,5-pdc)(Ac)(H2O)·2H2O]n(2,5-pdc=2,5-吡啶二羧酸根),通过X射线衍射确定了配合物的晶体结构.结果表明,该配合物为单斜晶系,P2(1)/c空间群.在配合物中,Pr(Ⅲ)离子是9配位的,通过醋酸根和2,5-吡啶二羧酸根将配合物连成3D网状结构.室温下测定了配合物晶体粉末的IR光谱,UV-Vis-NIR光谱以及可见区和近红外区的发射光谱.重点研究配合物的发光性能,该配合物在近红外区表现出Pr(Ⅲ)离子的特征发射带,与Pr(Ⅲ)离子的理论发射带相比发生了红移和劈裂现象,可以从配合物的UV-Vis-NIR吸收光谱中得到佐证.  相似文献   

2.
在水热条件下合成了一个新颖的Pr(Ⅲ)配合物[Pr(pda)0.5(nbca)2(H2O)2](pda=间苯二乙酸,nbca=5-硝基[1,1'-联苯]3-羧酸),并利用元素分析、X-单晶衍射、红外光谱、热重分析等对其进行表征.结果表明,该配合物属于单斜晶系,空间群为C12/c1,a=2.726 38(13)nm,b=1.010 66(5) nm,c=2.143 87(10)nm,β=94.258(1)°,V=5.891 0(5)nm3,Z=8.晶体结构分析表明:在该配合物中pr3+离子是1个8配位的配合离子,2个配体作为间隔物将稀土金属离子Pr3+链接形成[-Pr-pda-Pr-nbca-]nZ字形链,由5-硝基[1,1'-联苯]3-羧酸羧基的桥连支撑将1维链拓展为2维(6,6)波浪网面.  相似文献   

3.
以LnCl3、H2bpdc(2,2’-联吡啶3,3’-二甲酸)和phen(邻菲咯啉)为原料,在水热条件下合成了一系列稀土配合物[Ln(bpdc)1.5(phen)(H2O)].xH2O(Ln=La(1),Sm(3)和Dy(5),x=0;Ln=Pr(2)和Gd(4),x=0.15),并通过单晶X-射线衍射分析法测定了它们的晶体结构.此外,对配合物3和5的荧光性质和配合物2和4的磁性质进行了研究.结果表明,配合物3和5在室温下均表现出相应稀土离子的特征荧光发射,在配合物2和4的稀土离子间均存在反铁磁相互作用.  相似文献   

4.
制备了香兰素(3-甲氧基-4-羟基苯甲醛)对甲苯胺希夫(Schiff)碱硝酸稀土配合物。该配合物由一个中心稀土离子,二个单齿配位希夫碱,二个双齿配位硝酸根和一个外界硝酸根组成,中心稀土离子的配位数是6,其一般式为[LnL_2(NO_3)_2]NO_3(Ln=La, Ce, Pr, Nd, Sm, Eu; L=希夫碱配体)。  相似文献   

5.
合成了轻稀土离子 (La3 ,Ce3 ,Pr3 ,Nd3 ,Sm3 ,Eu3 )与 4 羟基安替比啉 (HOAP)和水杨酸 (HSal)的三元固态配合物 ,并用元素分析、红外光谱、紫外光谱、热分析、摩尔电导作了表征 .确定新配合物组成为 :[RE(OAP) (Sal) 2 (H2 O) 2 ].  相似文献   

6.
采用凝胶法合成了碱土金属—粘液酸配合物的晶体.样品经过元素分析、红外光谱研究,确定了该类配合物的组成.结果表明,粘液酸的两个羧基和四个羟基均能参与配位键的形成,而中心离子 Ca~(2+)、Sr~(2+)、Ba~(2+)与配体粘液酸的配位状况存在着一定差异。  相似文献   

7.
以LnCl3、H2bpdc(2,2'-联吡啶3,3'-二甲酸)和phen(邻菲咯啉)为原料,在水热条件下合成了一系列稀土配合物[Ln(bpdc)15 (phen)(H2O)]·xH2O(Ln=La(1),Sm(3)和Dy(5),x=0;Ln=Pr(2)和Gd(4),x=0.15),并通过单晶X-射线衍射分析法测定了它们的晶体结构.此外,对配合物3和5的荧光性质和配合物2和4的磁性质进行了研究.结果表明,配合物3和5在室温下均表现出相应稀土离子的特征荧光发射,在配合物2和4的稀土离子间均存在反铁磁相互作用.  相似文献   

8.
采用水热合成的方法,以邻苯二甲酸、己二酸为配体,合成了一种具有3D无限结构的Pr(Ⅲ)配位聚合物[Pr2(C8H4O4)2(C6H8O4)·4H2O]n(C8H4O4=邻苯二甲酸根;C6H8O4=己二酸根).通过X射线单晶衍射确定了该配聚物的晶体结构,结构分析表明该配聚物为三斜晶系,P1空间群,其不对称单元中含有2个不等效的Pr(Ⅲ)离子,配位数分别为8和9.在晶体中,Pr(Ⅲ)离子被邻苯二甲酸根和己二酸根连成了3D无限网状结构.在室温下,测定了其固态粉末的IR(红外),UV-Vis-NIR(紫外-可见-近红外)吸收光谱以及可见区和近红外区荧光激发和发射光谱,并对其进行了分析与指认.此外,该配聚物在近红外区表现出了Pr(Ⅲ)离子的特征发射,应主要归功于配体的敏化作用,并且该发射带与Pr(Ⅲ)离子的理论发射带相比出现了位移现象,也与配聚物的UVVis-NIR吸收光谱可相互佐证.  相似文献   

9.
以N,N-二(亚磷酸基甲基)-亚胺(简称H4IMPA)为配体,合成了2种新的稀土配合物[Ln2(IMPA) (H3IMPA)2](Ln=Pr(1),Nd(2)),并通过元素分析、紫外可见光谱、热分析、单晶X-射线衍射等方法对配合物 进行了表征.配合物1和2是同构的,属于单斜晶系,P21/C空间群.  相似文献   

10.
采用水热方法合成了1个新的Ni(Ⅱ)配合物{[Ni3(dcp)2(phen)2(H2O)6]·4H2O}(H3dcp=吡唑-3,5-二羧酸).对该配合物进行了单晶X射线衍射结构表征及UV-Vis-NIR吸收光谱,IR光谱和表面光电压光谱(SPS)性质测定.结构分析表明,该配合物为三核Ni(Ⅱ)配合物,其中2个Ni(Ⅱ)离子[Ni2(Ⅱ)、Ni2A(Ⅱ)]是晶体学等效的,另外1个Ni1(Ⅱ)离子与它们是不等效的.每个Ni(Ⅱ)离子均为6配位[Ni1(Ⅱ)离子配位模式为N2O4,Ni2(Ⅱ)和Ni2A(Ⅱ)离子配位模式为N3O3],配位构型均为畸变的八面体.配合物最终由氢键网联成具有2D结构的超分子.配合物的表面光电压光谱的测定结果表明,它在300~800nm范围内呈现出正的表面光伏响应,表明它具有一定的光电转换能力.同时对配合物的UV-Vis-NIR吸收光谱和IR光谱进行了分析和指认.  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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