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1.
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   

2.
从S-苄基二硫代时基甲酸酯(H_2NNHCSSCH_2C_6H_5)衍生出的两种希夫碱——邻氯苯甲醛希夫碱O—CIC_6H_4CHNNHC(S)SCH_2C_6H_5和亚苄基丙酮希夫碱C_6H_5CHCHC(CH_3)NNHC(S)SCH_2C_6H_5为配体,合成了与镍和铜的四种新的螯合物。对这些配合物进行了化学分析以及电导,磁性、紫外-可见光谱和红外光谱等性质的研究。结果表明,Ni(Ⅱ)与上述两种配体形成具有[NiA_2]和[NiB_2]形式的反磁性的平面正方形配合物,其中配体为单价双齿阴离子配体。Cu(Ⅱ)与邻氯苯甲醛希夫碱形成反磁性的Cu(Ⅰ)配合物[Cu(HA)A]。Cu(Ⅱ)与亚苄基丙酮希夫碱形成室温下磁矩为1.44B.M.的双核配合物[Cu_2Cl_2B_2],其中每个Cl桥与两个Cu(Ⅱ)相连,每个Cu(Ⅱ)具有平面正方形的配位结构。  相似文献   

3.
从S-苄基二硫代肼基甲酸酯(H_2NNHCSSCH_2C_6H_5)衍生出的两种希夫碱——邻氯苯甲醛希夫碱O—CIC_6H_4CHNNHC(S)SCH_2C_6H_5和亚苄基丙酮希夫碱C_6H_5CHCHC(CH_3)NNHC(S)SCH_2C_6H_5为配体,合成了与镍和铜的四种新的螯合物。对这些配合物进行了化学分析以及电导,磁性、紫外-可见光谱和红外光谱等性质的研究。结果表明,Ni(Ⅱ)与上述两种配体形成具有[NiA_2]和[NiB_2]形式的反磁性的平面正方形配合物,其中配体为单价双齿阴离子配体。Cu(Ⅱ)与邻氯苯甲醛希夫碱形成反磁性的Cu(Ⅰ)配合物[Cu(HA)A]。Cu(Ⅱ)与亚苄基丙酮希夫碱形成室温下磁矩为1.44B.M.的双核配合物[Cu_2Cl_2B_2],其中每个Cl桥与两个Cu(Ⅱ)相连,每个Cu(Ⅱ)具有平面正方形的配位结构。  相似文献   

4.
以对硝基苯甲酸、乙二醇、1,4-丁二醇及水杨醛等化合物为原料,经多步反应合成2种新型双希夫碱化合物(1c、2c),利用红外光谱、紫外光谱、核磁氢谱、元素分析对2种双希夫碱化合物进行结构表征.  相似文献   

5.
以邻香草醛和4,4′-二氨基二苯醚为原料,合成双邻香草醛希夫碱。通过单因素实验讨论了不同溶剂、反应时间、反应温度和物料物质的量之比对希夫碱产率的影响,并采用IR、1H 和13C核磁、元素分析等手段对产物希夫碱结构进行了表征。希夫碱合成的适宜工艺条件为:溶剂为四氢呋喃,反应温度35 ℃,反应时间1 h,邻香草醛与4,4′-二氨基二苯醚的物质的量之比为2〖DK〗∶1,在此条件下希夫碱产率达到697 %。  相似文献   

6.
用吡啶-2-甲醛与异烟肼在乙醇溶剂中,缩合反应得黄色吡啶-2-甲醛缩异烟肼希夫碱。所得的希夫碱与Nd3+、Y3+、Sm3+稀土金属盐反应制备得到金属配合物,并对配合物进行了UV和IR光谱等表征及相应的生物活性试验。  相似文献   

7.
含硫双Schiff碱配合物的合成与荧光性质研究   总被引:2,自引:0,他引:2  
近年来Schiff碱配合物的合成颇引人注目,缘于其结构的多样化^[1]及多种应用前景.席夫碱类化合物特别是含硫Schiff碱,由于其具有良好的抑菌、抗病毒和抗肿瘤等生物活性而引起国内外学者的关注^[2,3].但文献中对席夫碱过渡金属配合物的荧光性质的研究鲜有报道,本文合成了尚未见文献报道的双Schiff碱2,3-丁二酮缩氨基硫脲的过渡金属配合物,合成路线如图1所示.并对其荧光性质作了初步的研究.  相似文献   

8.
合成了一种新的希夫碱配合物 [MnL(Ac) (H2 O) ]Ac·H2 O(L表示糠醛缩邻苯二胺 )。通过元素分析、IR、UV和摩尔电导分析等手段 ,对合成的配合物进行了表征 ,并用非等温热重法研究了锰配合物的热分解反应动力学。推断出第一步和第三步热分解动力学方程分别为 :dα dt=A·e-E RT·3 2 (1-α) 4 3[1 (1-α) 1 3- 1]- 1 ;dα dt=A·e-E RT·(1-α) 2 。  相似文献   

9.
镧系大环希夫碱配合物的研究(英文)   总被引:1,自引:0,他引:1  
在水合镧系硝酸盐 ( )的存在下 ,2 ,2 (-亚乙二氧基 )双苯甲醛与二亚乙基三胺在乙醇介质中形成了配合物 RE(OH) (NO3) 2 L· 2 CH3CH2 OH (RE=La~ Nd) (L是相应的希夫碱大环 ) ,且进行了元素分析、摩尔电导、红外光谱和 TG- DTA分析等性质表征 .结果表明 ,配合物的可能结构式为 [Ln(OH) (NO3) L] NO3·2 CH3CH2 OH,其中镧系离子的配位数为 8.  相似文献   

10.
合成了两个席夫碱配体L~1(N,N'-双(苯甲酰丙酮)-1,2-乙二胺)和L~2(N,N'-双(乙酰丙酮)-1,2-丙二胺),然后将配体L~1和L~2分别与Ag NO_3进行配位反应,得到配合物[Ag_2(L~1)(NO_3)_2]_n(1)和[Ag_2(L~2)_2(NO_3)_2]_n(2),采用红外光谱、元素分析、热重分析、X-粉末衍射和X-射线晶体衍射对配合物进行了表征。结果表明:配合物1系三斜晶系,空间群为P-1;配合物2系单斜晶系,空间群为P2_1/c.在配合物1中,每个Ag(Ⅰ)离子都为扭曲三角双锥的配位模式,分别与配体L~1的O原子,另外一个配体L~1的γ-C原子,一个NO_3~-的两个O原子,另外一个NO_3~-的一个O原子配位形成二维网状结构。在配合物2中,每个Ag(Ⅰ)离子也均为扭曲三角双锥的配位模式,分别与同一配体L~2的两个γ-C原子,另外一个配体L~2的O原子以及NO_3~-的两个O原子配位形成一维链状结构。  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.
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   

20.
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   

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