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1.
采用水热合成法,使用油酸作为乳化剂制备了Yb3+/Er3+共掺杂六角相Na(Y1.5Na0.5)F6纳米棒。通过X射线衍射(XRD)、扫描电子显微镜(SEM)以及荧光光谱等测试手段对所制备的样品进行表征。测试结果表明,Na(Y1.5Na0.5)F6纳米晶的晶格常数为a=b=0.600 nm,c=0.352 nm。在980 nm红外光激发下,Yb3+/Er3+共掺杂Na(Y1.5Na0.5)F6纳米棒发出从红光到近紫外的上转换荧光,其中红光、绿光和近紫外光分别对应于Er3+离子4F9/2→4I15/2,(2H11/2,4S3/2)→4I15/2和(2G11/2/2H9/2)→4I15/2的能级跃迁。详细讨论和分析了各荧光波段的上转换发射过程。  相似文献   

2.
Na2[(VO)12O6B18O39(OH)3]·(11H3O)·4H2O的水热合成和晶体结构   总被引:5,自引:0,他引:5  
以V2O5, Na2B4O7·0H2O, NaH2PO4·2H2O, 乙二胺和H2O为原料, 按物质的量比0.5∶1∶1∶2.24∶111在180 ℃条件下晶化, 得到棕色晶体Na2[(VO)12O6B18O39(OH)3]·(11H3O)*4H2O. 单晶结构分析结果表明该化合物属单斜晶系, P21/n空间群, 晶胞参数 a=1.389 70(8) nm, b=1.661 59(9) nm, c=1.427 48(8) nm, β=95.691 0(10)°. Z=4, R=0.054 9. 该化合物的结构主要由阴离子簇[(VO)12O6B18O39(OH)3]13-构成. 该阴离子簇由B18O39(OH)3十八元环夹在两个以共边方式交替相连形成的V6O15簇中间, 通过共用氧原子形成三明治式结构新颖的硼-钒-氧阴离子簇, 结构中Na+以离子键方式将阴离子簇相互连接, 形成二维层状结构. 层与层之间通过分子间氢键相互作用. 价态计算结果表明, 结构中n(VⅣ)∶n(VⅤ)=5∶1.  相似文献   

3.
Alluaudite-type NaMnV2(PO4)3 single crystal was successfully synthesized in the NaCl molten-salt media. The single-crystal diffraction data analysis shows that NaMnV2(PO4)3 crystallizes in monoclinic C2/c space group with a = 12.098(2), b = 12.415(2), c = 6.4543(11) ?, β = 114.614(2)°, V = 881.3(3) ?3, Mr = 464.64, Dc = 3.50158 g/cm3, μ(Mo Kα) = 4.046 mm-1, F(000) = 892.4 and Z = 2. The structure consists of MnO6, VO6 octahedra and PO4 tetrahedra, which form a three-dimensional architecture with two sets of large Na+ tunnels. The intercalation/deintercalation properties of NaMnV2(PO4)3 as positive and negative electrodes were tested in sodium batteries.  相似文献   

4.
A new series °f 11-pyridyl substituted dibenz°-diazepin-1-°ne derivatives 1 was synthesized by a tw° step cycl°c°ndensati°n reacti°n. All the c°mp°unds were characterized by IR,MS, and 1H NMR. And crystals °f 1a and 1b were °btained and determined by X-ray single-crystal diffracti°n. Crystal data °f 1a: C48H52N6O7, m°n°clinic system, space gr°up C2/c, a = 28.39(4), b =9.275(12), c = 16.84(2) A, β = 104.98(3)°, V = 4284(10) A3, Z = 4, F(000) = 1752, Dc = 1.279 g/cm3,R = 0.0603, and wR = 0.1314. Crystal data °f 1b: C24H21N3 O, m°n°clinic system, space gr°up P21/c,a = 11.625(5), b = 19.055(9), c = 8.741(4) A, β = 95.547(6)°, V = 1927.2(15) A3, Z = 4, F(000) =776, Dc = 1.266 g/cm3, R = 0.0494, and wR = 0.1287.  相似文献   

5.
水热法合成了新结构类型化合物CsIn[P03(0H)]2,并通过单晶X-射线衍射表征结构.标题化合物空间群为P121/c1(No.14),晶体学参数为:M=439.69,mP56,a=0.532 86(6)nm,b=0.91653(7)nm,c=1.478 39(14)nm,β=93.849(9).,V=0.7204(1)nm3,Z=4,Dx=4.054 g·cm-3,μ=8.713 mm-1,F(000)=800,R1= 0.0325,wR2=0.0874.在该化合物中,2个In06八面体和4个PO4四面体形成交连的六元环柱,并沿a轴方向形成近六方密堆积并连接成Cs+离子占据的十二元环结构隧道,六元环和十二元环连接构筑了三维网络结构.与类似化学计量比化合物Na2In2[PO3(0H)]4·H2O比较,标题化合物中十二元环的形成明显取决于隧道阳离子的大小,其拓扑构造可看作扩展的6,3-网格连接,化合物RbIn[PO3(0H)]2与之同构.  相似文献   

6.
黄维垣  张龙庆 《化学学报》1985,43(9):852-858
合成了一些氟氯代β-二酮镧系螯合物(CF2ClCOCHCOR)3Ln.nH2O(2,Ln=Eu:2a,R=C(CH3)3,n=O;2b,R=C6F5,n=0;2c,R=CF2Cl,n=2.3,Ln=Pr:3a,R=C(CH3)3,n=0;3b,R=C6F5,n=1;3c,R=CF2Cl,n=2.4,Ln=La,R=C6H5,n=0).测试了化合物2和3的位移性能,其中2的位移性能与Eu(fod)3相近,而2b,2c,3b和3c则由于本身没有1H峰,故性能优于Eu(fod)3.化合物2和3易溶于CHCl3和CCl4等非极性有机溶剂。  相似文献   

7.
A new reduced molybdenum(Ⅴ) phosphate (H3dien)2(H2dien)2[NaMo12O24 (OH)6 (H2PO4)(HPO4)5(PO4)2]·nH2O(n= 10.92,dien = diethylenetriamine) has been synthesized under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. C16H96.84MO12N12NaO72.92P8 (Mr = 3046.73) crystallizes in the monoclinic system, space group P21/c with a = 13.3575(18), b = 21.907(3), c = 15.654(2) A, β= 110.22(2)°, V= 4298.4(10) (A)3, Dc = 2.354 g/cm3, Z = 2, μ(MoKα) = 1.966 mm-1, F(000) = 2990.4, the final R = 0.0357 and wR = 0.1086 for 8739 observed reflections with Ⅰ> 2σ(Ⅰ). It consists of sandwich-shaped cluster anions [Na{Mo6P4}2]10- held together into a three-dimensional supramolecular framework through intermolecular hydrogen-bonding contacts. A probe reaction of the oxidation of acetaldehyde with H2O2 showed that this compound has high catalytic activity in the reaction.  相似文献   

8.
A new reduced molybdenum(V) phosphate (H3dien)2(H2dien)2[NaMo12O24 (OH)6 (H2PO4)(HPO4)5(PO4)2]·nH2O (n = 10.92, dien = diethylenetriamine) has been synthesized under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. C16H96.84Mo12N12NaO72.92P8 (Mr = 3046.73) crystallizes in the monoclinic system, space group P21/c with a = 13.3575(18), b = 21.907(3), c = 15.654(2) , β = 110.22(2)°, V = 4298.4(10) 3, Dc = 2.354 g/cm3, Z = 2, μ(MoKα) = 1.966 mm-1, F(000) = 2990.4, the final R = 0.0357 and wR = 0.1086 for 8739 observed reflections with I > 2σ(I). It consists of sandwich-shaped cluster anions [Na{Mo6P4}2]10- held together into a three-dimensional supramolecular framework through intermolecular hydrogen-bonding contacts. A probe reaction of the oxidation of acetaldehyde with H2O2 showed that this compound has high catalytic activity in the reaction.  相似文献   

9.
黄维垣  黄炳南  王巍 《化学学报》1985,43(7):663-668
应用相转移催化和加入共溶剂的技术,全氟碘代烷如Cl(CF2)2I(1a)、Cl(CF2)4I(1b),Cl(CF2)6I(1c),H(CF2)8I(1d),C4F9I(1e),C6F13I(1f),C8F17I(1g)及α,ω-全氟二碘代烷如(ICF2CF2)2O(3a),I(CF2)6I(3b),I(CF2)8I(3c),I(CF2)10I(3d)等均可与连二亚硫酸钠水溶液在温和的条件下发生亚磺化脱碘反应,生成全氟亚磺酸盐Cl(CF2)2SO2Na(2a),Cl(CF2)4SO2Na(2b),Cl(CF2)6SO2Na(2c),H(CF2)8SO2Na(2d),C4F9SO2Na(2e),C6F13SO2Na(2f),C8F17SO2Na(2g)及O(CF2CF2SO2K)255a),KO2S(CF2)6SO2K(5b),KO2S(CF2)8SO2K(5c),KO2S(CF2)10SO2K(5d)全氟α,ω-二亚磺酸钠易潮解,均转化为相应的钾盐。这些亚磺酸盐均可用常规方法氯化成对应的磺酰氯,从而提供了由全氟碘代烷、二碘代烷制备全氟亚磺酸盐、二亚磺酸盐及全氟磺酸,二磺酸及衍生物的一种实用方法。  相似文献   

10.
合成了苯并 15 冠 5、二苯并 18 冠 6与Na2 [Pt(SCN) 6]的配合物 :[Na(B15 C 5 ) ]2 [Pt(SCN) 6](1) ,[Na(DB18 C 6 ) ]2 [Pt(SCN) 6](2 ) ,并通过元素分析、红外光谱、单晶X射线衍射进行了表征 .1为单斜晶系 ,空间群P2 1/c,a =1.0 974(5 )nm ,b =1.5 187(7)nm ,c=1.36 32 (6 )nm ,β =96 .40 7(7)°,V =2 .2 5 6 8(18)nm3 ,Z =2 ,Dcalcd=1.746g/cm3 ,F(0 0 0 ) =1184,R1=0 .0 35 7,wR2 =0 .0 86 8.2为三斜晶系 ,空间群P1- ,a =1.2 5 0 0 (3)nm ,b =1.2 82 5 (3)nm ,c=1.934 2 (4 )nm ,α=10 6 .82 (3)° ,β =10 2 .5 1(3)° ,γ =10 3.0 4(3)°,V =2 .75 6 2nm3 ,Z =2 ,Dcalcd=1.5 79g/cm3 ,F(0 0 0 ) =1316 ,R1=0 .0 36 4,wR2 =0 .0 771.配合物分别由两个 [Na(B15 C 5 ) ]+ ,[Na(DB18 C 6 ) ]+ 配阳离子和一个[Pt(SCN) 6]2 -配阴离子组成 .配阳离子和配阴离子通过Na—N键形成二维网状结构  相似文献   

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HEPT类化合物的QSAR研究   总被引:3,自引:0,他引:3  
章文军  许禄 《应用化学》2001,18(9):717-0
为定量结构/活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法(Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物(1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构/活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。  相似文献   

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The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971  相似文献   

16.
The dependence of the chemical shift of the ring protons on the pH of the medium for a number of 3-hydroxyquinoline derivatives was studied by PMR spectroscopy. The regions of ionization of the molecules, which correspond to the ranges of acidic, neutral, and alkaline media, were found. In D2O, 3-hydroxyquinoline is present only in the uncharged hydroxy form. The presence of intramolecular hydrogen bonding in 4-dimethylaminomethyl-3-hydroxyquinoline has a substantial effect on the character of the dependence of the chemical shift on the pH of the medium; the existence of separate protonation of the nitrogen atoms of the ring and the side chain of 4-dimethylaminomethyl-3-hydroxyquinoline was established. The distribution of the -electron density in the 3-hydroxyquinoline molecule is in good agreement with its chemical behavior during electrophilic substitution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1545, November, 1971.  相似文献   

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Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.  相似文献   

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