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1.
用微波辐射法合成了(Ce0.67Tb0.33)MgAl11O19(PG)和BaMgAl10O17(PB)两种荧光体,经X射线粉末衍射分析,其d值和I/I0值与JCPDF3673和26163基本一致。计算得到PG的晶胞参数a=05582nm,c=21884nm;P-B的晶胞参数α=05616nm,c=22614nm。测定了两种荧光体的激发光谱和发射光谱。P-G的色坐标x=0316,y=0565;P-B的色坐标x=0156,y=0106。与市售同类荧光粉相比,P-G的相对发光强度为88%,P-B的相对发光强度为80%。  相似文献   

2.
合成了两个异亚硝基乙酰丙酮-N-芳基亚胺的Pd(Ⅱ)配合物,PdCl(C6H5-IAI)(C6H5NH2)(1)和PdCl(p-CH3C6H4-IAI)(p-CH3C6H4NH2)(2),并测定了配合物1的晶体结构。配合物1晶体属正交晶系,空间群为Pca21,晶胞参数a=1.8587(4)nm,b=0.9380(2)nm,c=2.1237(4)nm,Z=8,F(000)=1760,μ=1.160m  相似文献   

3.
结果表明,LixNi0.3Co0.7O2具有六方晶系R3^-m空间群结构。当X-1,0.315时,其晶胞参数分别为a=2.826nm,c=14.130nm和a=0.2808nm,c=1.4253nm;MO6(M=Ni,Co)八面体中M-O平均距离分别为0。1941nm和0.1933nm。XPS分析结果表明LIxNi0.3CO0.7O2表面存在Li2O,同时探讨了其中过渡金属离子的3d电子结构变化。  相似文献   

4.
合成了3个分别以C2O2-4([Cu2(L1)2(ox)],1),AcO-([Cu2(AcO)(L2)2]BF4,2)和酚氧([Cu2(L3)2](ClO4)2,3)为桥基的双核铜配合物,并测定了1的复配合物[Cu2(L1)2(ox)]·[Fe(OH)2(H2O)4]ClO4·H2O(1′)及2和3的晶体结构.X射线衍射结果表明:1′,2和3分别属于Fddd,P21/c和P21/c空间群.晶胞参数:[Cu2(L1)2(ox)][Fe(OH)2(H2O)4]ClO4·H2O,a=2.4390(4)nm,b=3.0538(6)nm,c=1.8494(6)nm,α=β=γ=90.00°;2,a=0.847(1)nm,b=2.6542(8)nm,c=1.4100(6)nm,β=91.34(6)°;3,a=0.7646(3)nm,b=1.6983(3)nm,c=2.4417(3)nm,β=97.11°  相似文献   

5.
姚心侃  谢庆兰 《结构化学》1996,15(3):193-198
三环己基锡O,O’-二(4-氯苯基)二硫代磷酸酯(I),C30H41Cl2(O2PS2Sn,Mr=718.36,单斜晶系,P21/n,a=16.151(2),b=9.4159(1),c=22.987(3),A,β=105.69(1)°,Z=4,Dc=1.418g.cm^-3,R=0.063;二丁基锡双(O,O’-二(4-甲基苯基)二硫代磷酯酯(Ⅱ),C36H46O4P2S4Sn,Mr=851.66  相似文献   

6.
「Eu(p-ABA)3Phen;H2O」(C2H5OH)(p-0ABA=对氨基苯甲酸根,Phen=邻菲咯啉)配合物晶体属三斜晶系,P1^-空间群,a=1.226893)nm,b=1.4005(3)nm,c=1.0440(3)nm;a=102.6992),β=108.93(2),γ=92.85(2);Z=2,T=273K。  相似文献   

7.
合成了双氯桥双核钯配合物[Ph_2P(o-C_6H_4CO)PdCl]_2·2CH_2Cl_2进行了元素分析、红外光谱表征和晶体结构测定,研究了其催化氢化性能。在30~80℃、氢分压1.0~5.0MPa的范围内。发现该配合物是催化氢化丙烯酸为丙酸的有效催化剂.晶体[Pd_2Cl_2(C_(19)H_(14)OP)_2]·2CH_2Cl_2属P1空间群,a=0.9304(3)nm,b=1.0392(2)nm,c=1.1062(3)nm;a=102.78(2),B=97.35(3),γ=95.25(2),V=1.0264nm~3,M=1032.17,2=1,Dc=1.670g/cm~3,u=13.695cm~(-1),F(000)=512,用1945个独立衍射精修结构,最终R=0.036。  相似文献   

8.
合在了(Y(NTO)2NO3(H2O)5).2H2O(NTO为3-硝基-1,2,4-三唑-5-酮)并测定了晶体结构,晶体属单斜晶系,空间群Cm,晶胞参数:a=0.6773(2)nm,b=2.0866(2)nm,c=0.6551(1)nm;β=102.98(2)°V=0.9021(1)nm^3,Z=2,Dc=1.970g.cm^-3,μ=33.49cm^-1,F(000)=540,R=0.032,中  相似文献   

9.
首次合成了二价铕中性芳烃配合物[Eu(C6Me6(AlCl4)2]·Me4C6H2,并经红外光谱,激发光谱和荧光光谱表征,测定了晶体结构。配合物属单斜晶系,P2/c空间群,晶胞参数a=1.7652(4)nm,b=1.5918(4)nm,c=1.8752(5)nm;β=97.61(5)°,Z=2,R=0.0496,Rw=0.0462。  相似文献   

10.
合成了〔Mn2(bzacen)2(MeOH)2(μ-4,4′-bipy)〕(ClO4)2化合物,并测定其晶体结构。该晶体属单斜晶系,空间群P21/n,晶胞参数:a=1.3082(3)nm,b=1.2713(3)nm,c=1.8006(5)nm,β=110.91(2)°,Z=2,μ=5.97cm^-1,R=0.0580,GOF=1.66。在配合物阳离子中,4,4′-联吡啶桥联2个〔Mn(bzacen  相似文献   

11.
A method for high-precision and high-accuracy mass spectrometric measurements of the ratios among the three oxygen isotopes, and of the O(2)/Ar ratio, is presented. It involves separation of the O(2)-Ar mixture from air and includes a fully automated system that ensures highly reliable sample processing. Repeated measurements of atmospheric oxygen yield the repeatability (+/-SE x t, standard error of the mean (n = 12) multiplied by Student's t-factor for a 95% confidence limit) of 0.004, 0.003 and 0.2 per thousand for delta(18)O, delta(17)O and delta O(2)/Ar, respectively.  相似文献   

12.
We have optimized the method of water fluorination using the solid reagent CoF3 to produce O2. This allows isotope ratio measurements by dual-inlet mass spectrometry with very high precision of 0.01 to 0.03/1000 for both delta17O and delta18O. Using this method, delta17O and delta18O of atmospheric O2 were determined as 12.08 and 23.88/1000 vs. VSMOW, respectively. Likewise, delta17O and delta18O of GISP were -13.12 and -24.73/1000, and for SLAP they were -29.48 and -55.11/1000 vs. VSMOW, respectively. Analysis of these data in a ln(delta17O + 1) vs. ln(delta18O + 1) plot yields a line with a regression coefficient (lambda) of 0.5279 +/- 0.0001 (R2 = 0.999999). We also determined the fractionation factors 17alpha and 18alpha in liquid-vapor equilibrium, and found that the ratio ln 17alpha/ln 18alpha is constant (0.529 +/- 0.001) over the temperature range 11.4 to 41.5 degrees C.  相似文献   

13.
14.
We present the results of our investigations on the electrooptic properties of the smectic O and O* phases of m7tac (1-methylheptyl terephthalylidene-bis-4-aminocinnamate). At low voltages, we observed striking electrochromic effects and, in O* at high voltages, a field induced phase transition. Freely suspended thick films of m7tac in the O and O* phases are weakly biaxial. A framework is proposed to account for our observations.  相似文献   

15.
Abstract

We present the results of our investigations on the electrooptic properties of the smectic O and O* phases of m7tac (1-methylheptyl terephthalylidene-bis-4-aminocinnamate). At low voltages, we observed striking electrochromic effects and, in O* at high voltages, a field induced phase transition. Freely suspended thick films of m7tac in the O and O* phases are weakly biaxial. A framework is proposed to account for our observations.  相似文献   

16.
17.
Laser Raman studies on two compounds of the α,ω-bis(4-alkylanilinebenzylidene -4′-oxy)alkane series were carried out in the spectral regions 1140–1220 and 1550–1650 cm-1 as a function of temperature. Compounds 7.O4O.7 and 7.O5O.7, exhibit SmA and SmF phases. The structural differences between these liquid crystal dimers, having either an odd or an even number of carbon atoms in the spacer, are remarkably existent in the room temperature Raman spectra. The results are rationalized on the basis of the tendency of these compounds to exhibit bent shapes, and how this manifests in the odd-even effect at the molecular level assuming a semi-rigid core region of the dimeric molecule. It is found that the behaviour of the odd spacer dimer (7.O5O.7) agrees with the molecular model, whereas the even spacer dimer (7.O4O.7) behaves in a similar fashion to monomeric compounds such as the nO.m. compounds. In both cases, dynamic changes around the C=N bond have a profound effect both on the molecular shape in the different phases and on phase behaviour.  相似文献   

18.
19.
A C-C bond-breaking reaction has been observed when a beam containing hyperthermal oxygen was directed at a continuously refreshed saturated hydrocarbon liquid (squalane) surface. The dynamics of this C-C bond-breaking reaction have been investigated by monitoring time-of-flight and angular distributions of the volatile product, OCH3 or H2CO. The primary product is believed to be the methoxy radical, OCH3, but if this radical is highly internally excited, then it may undergo secondary dissociation to form formaldehyde, H2CO. Either the primary or the secondary product may scatter directly into the gas phase before thermal equilibrium with the surface is reached, or they may become trapped on the surface and desorb in thermal equilibrium with the surface. Direct, single-collision scattering events that produce a C-C bond-breaking product are described with a kinematic picture that allows the determination of the effective surface mass encountered by an incident O atom, the atom-surface collision energy in the center-of-mass frame, and the fraction of the center-of-mass collision energy that goes into translation of the scattered gaseous product and the recoiling surface fragment. The dynamical behavior of the C-C bond-breaking reaction is compared with that of the H-atom abstraction reaction, which was the subject of an earlier study. Another reaction, H-atom abstraction by O2 (which is present in the hyperthermal beam), has also been observed, and the dynamics of this reaction are compared with the inelastic scattering dynamics of O2 and the dynamics of H-atom abstraction by O. The dynamics involving direct inelastic and reactive scattering of O2 are also described in terms of a kinematic picture where the incident O2 molecule is viewed as interacting with a local region of the surface.  相似文献   

20.
W/O与O/W,W/O与双连续结构微乳液的界面电性质   总被引:2,自引:0,他引:2  
刘天晴  魏逊  郭荣 《化学学报》2002,60(4):633-638
无探针伏安法和电容法测定结果表明,在质量比H_2O/n-C_5H_(11)OH = 50/50条件下,SDS总含量<3%时,上相呈W/O结构,下相呈O/W结构,随着体系SDS 总含量的增大,界面上SDS量增加,界面电势ΔE、界面电容C、界面电荷传递电流 i_p均增加,而界面电阻率ρ_i则减小;当体系 SDS总含量≥3%时,上相呈W/O结构 ,下相呈双边续结构,各界面电性质变化幅度均变缓。  相似文献   

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