首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4篇
  免费   0篇
  国内免费   7篇
化学   11篇
  2011年   1篇
  2006年   1篇
  2005年   3篇
  2004年   1篇
  2003年   2篇
  2002年   2篇
  2001年   1篇
排序方式: 共有11条查询结果,搜索用时 15 毫秒
1.
IntroductionCertainlanthanideionspossessharpemissionlinesinthevisibleregions.Thepossibilityoftransferringenergyeffi cientlytotheseionsbywayofstronglyabsorbingtransitionscharacteristicoforganicligandshasspurredmanyworkerstoinvestigatelanthanidechelatesaspotentiallasermaterials .Amongthemtheternarycomplexesofeuropium(III)andter bium(III)withtris(β diketonates)andanneutralligandhaveespeciallyattractedmuchattentionfortheirstronglumi nescence.Itmakethemaextensiveapplicationsindevelop mentofnewl…  相似文献   
2.
A lariat crown ether ligand 7,16-bis (2-hydroxy-5-methylbenzyl)- 1,4,10,13-tetraoxa-7,16-diazacyclooctadeeane (L1) has been prepared via one-pot Mannich reaction. Its copper(Ⅱ) complex Cu-L1 was synthesized and characterized by elemental analysis, IR and UV-visible spectroscopy. The crystal structure of the complex has been determined by X-ray diffraction analysis. The result shows that the copper(Ⅱ) ion is six-coordinated by two nitrogen and four oxygen atoms, two from the crown ether and the other two from the deprotonated phenolate anions, forming an elongated octahedral complex. Electrochemical study indicates that the complex undergoes reversible reduction in DMF solution.  相似文献   
3.
郭倩玲  马淑兰  朱文祥  刘迎春  张静 《中国化学》2005,23(10):1387-1390
The X-ray crystallographic structure was reported for a dinuclear copper(Ⅱ) complex with a tetraanionic ligand of p-tert-butylsulfonylcalix[4]arene [Cu2L(CH3OH)6]·4CH3OH (H4L=p-tert-butylsuffonylcalix[4]arene). The complex belongs to triclinic system, P1^-- space group, with a = 1.2303(3) nm, b = 1.2377(3) nm, c = 1.3110(3) nm, a =66.862(4)°, β= 67.206(4)°, γ=61.711(3)°, Z= 1, V= 1.5659(7) nm^3, Dc= 1.371 g/cm^3, F(000) = 682,μ(Mo Kα) = 0.883 mm^-1, R1 =0.0325, wR2=0.0870. In this complex, the calix[4]arene acts as a bis-tridentate chelating ligand with the 1,2-alternate conformation.  相似文献   
4.
硫杂杯[4]芳烃氧化膦衍生物的合成与晶体结构   总被引:3,自引:1,他引:2  
合成了部分取代的硫杂杯[4]芳烃氧化膦衍生物, 二(亚甲基二苯基氧化膦)对叔丁基硫杂杯[4]芳烃(化合物1), 培养了化合物的单晶, 用Smart 1000 CCD衍射仪测定了其晶体结构. 结果表明, 1的组成为: C66H70O6P2S4•2CH3OH, 属三斜晶系, P1空间群, 晶胞参数a=1.3453(6) nm, b=1.5289(7) nm, c=1.7893(9) nm; α=75.707(9)°, β=69.131(8)°, γ=79.734(9)°, Z=2; V=3.316(3) nm3, d=1.215 g/cm3, F(000)=1288, μ (Mo Kα)=0.244 mm-1, R1=0.0625, wR2=0.1372. 杯芳烃分子采取了锥式构象.  相似文献   
5.
郭倩玲  朱文祥 《合成化学》2001,9(2):138-141
首次合成了稀土(Ⅲ)- 三氟乙酰丙酮(TFA)-4-皮考林-N-氧化物(4-picNO)混配配合物,通过元素分析确定其组成为Ln(TFA)2(3-picNO)(Ln=La,Nd,Eu,Tb),通过电导率,紫外光谱,IR和荧光光谱的测试,讨论了它们的性质。  相似文献   
6.
Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide(PNO) and p-sulfonatothiacalix[4]arene(H4TCAS4-):[Ln2(PNO)2(H2O)10?(H2TCAS)2].[Ln2(H2TCAS)2(H2O)6(MeOH)2].2MeOH.12H2O(Ln = La,1;Nd,2).Crystal data for complex 1:C31H51La2NO33S8,Mr = 1500.03,triclinic system,P 1 space group,with a = 11.732(2),b = 15.007(3),c = 15.262(3),α = 78.05(3),β = 80.77(3),γ = 83.89(3)°,Z = 2,V = 2587.3(9)3,Dc = 1.925 g/cm3,μ = 2.051 mm-1,F(000) = 1500,the final R = 0.0300 and wR = 0.0823;and those for complex 2:C31H51Nd2NO33S8,Mr = 1510.69,triclinic system,P1 space group,with a = 11.719(2),b = 14.941(3),c = 15.157(3),α = 78.03(3),β = 80.84(3),γ = 83.95(3)°,Z = 2,V = 2555.9(9)3,Dc = 1.963 g/cm3,μ = 2.436 mm-1,F(000) = 1512,the final R = 0.0493 and wR = 0.1267.There are two coordination environments of lanthanide ions.One is bridged by two PNO molecules forming a dimeric Ln ion in the O,O'-μ2 mode.The dinuclear ions are shrouded by two H2TCAS6-ions through coordination interactions and hydrogen bonds.The other coordination mode of Ln ions is a zigzag 1D chain linked by up-down H2TCAS6-ions.By the coordination capsules,the complexes form 2D zigzag-ladder structure coordination polymers.  相似文献   
7.
我们都知道,由H2和N2合成氨需要高温、高压和催化剂。可是自然界进化出一种完全不同的不需高温、高压的更加精巧的合成路线,这就是通过固氮酶的生物固氮过程。该过程的特征,也是最诱人的地方是该合成反应可以在常温、常压的温和条件下进行。固氮酶只有在无氧条件下才能催化这种氧化一还原反应。  相似文献   
8.
Introduction  Transportofcationsacrossanorganicliquidmem branewhichseparatestwowaterphaseshasbeenexten sivelyinvestigated .1Thesyntheticmacrocyclicligands ,suchascrownethers ,areusuallyusedasmodelcarrierstomimicthenaturallyoccurringantibioticmacrocycleswhichhavebeenshowntoalterthepermeabilityofbiologicalmembranestocertaincations .2 ,3 Thus ,theyhaveimpor tantapplicationsinbothchemistryandbiologytoselectivecomplexationofvariousmetalcations .4 ,5Itwasreportedthatthedivalenttransition metalcomp…  相似文献   
9.
合成了5,11,17,23-四叔丁基-25,26,27-三[(乙酯基)甲氧基]-2,8,14,20-四硫酰杯[4]芳烃(L1)和5,11,17,23-四叔丁基-25,26,27-三(氧基乙酸)-2,8,14,20-四硫酰杯[4]芳烃(L2)及L2的稀土配合物, 采用元素分析、紫外光谱、红外光谱和1H NMR对其结构进行了表征. 用SMART 1000 CCD X射线衍射仪测定了L1的晶体结构. 结果表明, L1组成为: C52H65KO18S4·0.5H2O, 属三斜晶系, P1空间群, 晶胞参数a=1.2607(6) nm, b=1.5820(8) nm, c=1.6480(8) nm; α=83.720(8)°, β=69.327(8)°, γ=79.342(9)°, Z=2, V=3.019(3) nm3, Dc=1.270 g/cm3, F(000)=1218, μ=0.293 mm-1, R1=0.0937, wR2=0.2580. 杯芳烃分子采取部分锥式构象.  相似文献   
10.
合成了一种新型的四氮杂取代的三环结构冠醚4,13-二氧-1,7,10,16-四氮杂三环[14.2.1.17,10]二十烷(L7), 低温条件下在乙醚中培养出其单晶, 用X射线衍射法测定了晶体结构. 该晶体属单斜晶系, 空间群P21/n, 晶胞参数a=0.8984(7) nm, b=1.0805(9) nm, c=1.1040(9) nm; Z=2, β=111.707(13)°; V=0.9958(14) nm3, Dc=1.189 g/cm3, μ=0.092 mm-1, F(000)=392, R1=0.0649, wR2=0.1714. 制备了配体L7与金属盐的配合物, 分析结果表明, 配体L7与金属离子形成1∶1型的配合物.  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