CuW_(11)Cd/PANI掺杂材料的制备、表征及光催化性能

采用化学氧化法制得K_8[CuW_(11)CdO_(40)]/PANI掺杂材料,并用IR、UV、XRD、EDS、SEM对所合成的掺杂材料进行了表征。并利用所合成K_8[CuW_(11)CdO_(40)]/PANI掺杂材料为催化剂,研究了对亚甲基蓝溶液光降解催化活性。通过实验确定了光降解的最佳条件为:亚甲基蓝溶液初始pH为2,亚甲基蓝溶液初始浓度为10mg·L~(-1),催化剂用量为0.08 g,在光照100 min,亚甲基蓝溶液的脱色率为98.11%。因此,K_8[CuW_(11)CdO_(40)]/PANI掺杂材料是一种很好的光降解催化剂。     

三元复合材料K8[Fe（H2O）W11MnO39]/PANI/TiO2的制备及光催化性能

采用静电自组装法制备出三元复合材料K8[Fe（H2O）W（11）MnO（39）]/PANI/TiO2.采用IR,UV,XRD,SEM,XPS和N2吸附-脱附的表征手段对K8[Fe（H2O）W（11）MnO（39）]/PANI/TiO2进行表征,并以龙胆紫为模型,在紫外光照射下,考察了K8[Fe（H2O）W（11）MnO（39）]/PANI/TiO2对龙胆紫染料的光催化性能,确定光催化最佳条件：龙胆紫溶液浓度为5mg/L,pH=3,K8[Fe（H2O）W11MnO39]/PANI/TiO2的用量为10mg,脱色率可达92.93%.     

K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5复合材料制备、表征及光催化

本文采用直接合成法合成了K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5,又采用化学氧化法制得了PANI/V_2O_5,然后通过静电自组装法制得新的复合材料K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5/PANI/V_2O_5。并采用XRD、氮气吸附、FT-IR、SEM、UV、XPS手段进行表征。实验结果表明:K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5已与PANI/V_2O_5复合,并且保持杂多酸原有Keggin结构。以K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5/PANI/V_2O_5为催化剂降解亚甲基蓝,考察其光催化活性。确定最佳反应条件:亚甲基蓝溶液初始浓度为12 mg/L、pH=2、催化剂K_7[Cu(H_2O)W_(11)AlO_(39)]/PANI/V_2O_5/PANI/V_2O_5的用量为0.02g。在最佳条件下,亚甲基蓝的脱色率最高可达92.9%。     

复合材料K_8[Fe(H_2O)CdW_(11)O_(39)]/PANI/ZrO_2的制备、表征及光催化性能

采用静电自组装法制备了复合材料K_8[Fe(H_2O)CdW_(11)O_(39)]/PANI/ZrO_2.运用UV,IR,XRD,SEM-EDS和N_2吸附-脱附的检测手段对其进行了表征,并以该化合物作为催化剂,研究了其对孔雀石绿溶液的光降解情况.通过实验确定最佳的光降解条件:孔雀石绿溶液的初始浓度为25mg/L,孔雀石绿溶液的初始pH值为2,K_8[Fe(H_2O)CdW_(11)O_(39)]/PANI/ZrO_2的用量为0.05g.在最佳的条件下,孔雀石绿溶液的脱色率可达98.68%.因此,K_8[Fe(H_2O)CdW_(11)O_(39)]/PANI/ZrO_2是一种光催化性能良好的复合材料.     

LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料的合成、表征及光催化活性

用离子交换法制备了LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料,并利用IR,XRD,N_2吸附和脱附实验以及扫描电镜配合X-射线能量色谱仪(SEM-EDS)等方法对其结构和性质进行了表征.结果表明,[Cd(H_2O)W_(11)NiO_(39)]~(8-)杂多阴离子取代了黏土板层中的NO_3~-离子,并且仍然保留了Keggin结构.利用合成的复合材料LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)作为催化剂,对亚甲基蓝进行了光催化降解实验,并确定了光降解反应的最佳反应条件.在最佳反应条件下,亚甲基蓝的脱色率可达97.11%.并将复合材料与杂多酸盐和黏土的光催化活性进行了比较,其光催化活性顺序为LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)K_8[Cd(H_2O)W_(11)NiO_(39)]Zn_2Al黏土.因此,LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料具有优异的光催化活性.     

介孔结构Na_(10)[α-SiW_9O_(34)]/TiO_2/Ag的合成及光催化性能研究

本文采用溶胶-凝胶法制备Na10[α-Si W9O34]/Ti O2/Ag复合材料。用IR、XRD、UV‐Vis漫反射光谱、SEM、ED-Mapping等方法进行了表征和分析。用N2吸附-脱附等温线考察了催化剂的比表面、孔径,表明产物为介孔材料。以标题化合物作为光催化剂催化降解亚甲基蓝,探讨催化剂用量、亚甲基蓝的初始浓度、溶液的p H值等条件对亚甲基蓝脱色率的影响,结果表明:催化剂加入量为1 mg·L-1、亚甲基蓝的初始浓度为5 mg·L-1,p H=2.0,脱色率达到94.7%。     

K_8[Zn(H_2O)MnW_(11)O_(39)]/PANI/TiO_2复合材料的制备及光催化性能

采用直接合成法制备K_8[Zn(H_2O)Mn W_(11)O_(39)],以(NH_4)_2S_2O_8为氧化剂,通过化学氧化法将聚苯胺包覆在纳米Ti O_2颗粒表面制得PANI/Ti O_2,然后运用静电自组装法将K_8[Zn(H_2O)Mn W_(11)O_(39)]与PANI/Ti O_2复合成K_8[Zn(H_2O)Mn W_(11)O_(39)]/PANI/Ti O_2复合材料。运用IR、UV、XRD、XPS、SEM、N2吸附-脱附等分析方法对K_8[Zn(H_2O)Mn W_(11)O_(39)]/PANI/Ti O_2进行表征。利用K_8[Zn(H_2O)Mn W_(11)O_(39)]/PANI/Ti O_2为催化剂,研究其对孔雀石绿溶液的光催化降解性能。结果表明:紫外光照射下,孔雀石绿p H为2,浓度为20 mg/L,催化剂为10 mg时,脱色率可达93.66%。     

K_8[Cu(H_2O)ZnW_(11)O_(39)]/PANI/ZrO_2复合材料的制备与光催化性能研究

采用静电自组装法制备了复合材料K_8[Cu(H_2O)ZnW_(11)O_(39)]/PANI/ZrO_2,并采用IR、UV、XRD、N_2吸附-脱附、SEM、XPS、TG的检测手段对其进行了表征,且以制备的K_8[Cu(H_2O)ZnW_(11)O_(39)]/PANI/ZrO_2为催化剂,考察了K_8[Cu(H_2O)ZnW_(11)O_(39)]/PANI/ZrO_2的光催化活性,以二甲酚橙为模型,在紫外光照射条件下,确定最佳光催化条件为:二甲酚橙溶液的初始浓度为5 mg·L~(-1),二甲酚橙溶液的初始pH值为4,K_8[Cu(H_2O)ZnW_(11)O_(39)]/PANI/ZrO_2的用量为0.0200 g。最佳条件下,二甲酚橙溶液的脱色率可达93.72%。     

11-钨铬杂多阴离子层状材料的制备和表征及其光催化活性

采用离子交换法制备了具有Keggin结构11-钨铬三元杂多阴离子层状材料LDH-[Cu(H2O)W11Cr O39]7-,并利用红外光谱(IR)、X-射线衍射(XRD)和扫描电子显微镜配合X-射线能量色散谱仪(SEM-EDS)对其组成和结构进行了表征。结果表明:三元杂多阴离子[Cu(H2O)W11Cr O39]7-取代了粘土板层中的NO3-离子,并且仍然保留了Keggin结构。利用合成的层状材料LDH-[Cu(H2O)W11Cr O39]7-为催化剂,对孔雀石绿进行了光催化降解实验,确定了光降解反应的最佳反应条件.在最佳反应条件下,孔雀石绿的脱色率可达98.01%。并将层状材料与杂多酸盐和粘土的光催化活性进行了比较,其光催化活性顺序为:LDH-[Cu(H2O)W11Cr O39]7-K7[Cu(H2O)W11Cr O39]Zn2Al粘土。因此表明层状材料LDH-[Cu(H2O)W11Cr O39]7具有优异的光催化活性。     

H_3PW_(12)O_(40)/TiO_2(锐钛)的超声制备及降解染料的研究

采用超声法,在80℃下,制备了H3PW12O40/TiO2(锐钛)复合催化剂,并采用XRD、FT-IR等方法对样品进行了表征。通过染料刚果红和亚甲基蓝为模拟污染物的光催化降解实验考察了复合催化剂的光催化活性。结果表明,在太阳光下,复合光催化剂的催化活性高于单体TiO2,H3PW12O40/TiO2(锐钛)在90min内,对溶液中刚果红的去除率达99.17%,对亚甲基蓝溶液的TOC去除率达73.17%。复合催化剂在反复实验5次后,仍能保持有效的催化性能。     

High-precision measurements of 17O/16O and 18O/16O of O2 and O2/Ar ratio in air

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.     

High precision measurements of 17O/16O and 18O/16O ratios in H2O

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.     

Electrooptic response of smectic O and smectic O

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.     

Electrooptic response of smectic O and smectic O

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.     

Photooxidation of polystyrene by O2 and N2O

Strips of polystyrene held in a flowing O₂ or N₂O atmosphere have been exposed to 240-600 nm radiation. The extent of photooxidation has been followed by x-ray photoelectron spectroscopy (XPS). Although N₂O is a more reactive gas than O₂, it produces a less oxidized polymer surface. This surprising observation can be correlated to the photochemistry occurring at the gas/polystyrene interface. © 1992 John Wiley & Sons, Inc.     

Laser Raman studies on compounds 7.O4O.7 and 7.O5O.7

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.     

W/O与O/W，W/O与双连续结构微乳液的界面电性质

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。