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1.
为了降低质子交换膜(PEM)的甲醇渗透系数和改善PEM在中高温(80~120 ℃)时的质子传导率, 以自制的磺化度(SD)为100%的磺化聚芳醚酮砜(SPAEKS)与聚芳醚砜噁二唑(PAESO)为原料, 采用溶液共混法制备了SPAEKS/PAESO复合膜, 并用傅里叶变换红外光谱(FTIR)和热重分析(TGA)对其进行了表征. 结果表明, 该复合膜具有较好的化学稳定性和热稳定性. 扫描电子显微镜(SEM)照片显示, 复合膜具有较好的致密结构, 其甲醇渗透系数为3.9×10-7~6.6×10-7 cm2/s, 低于SPAEKS的8.7×10-7 cm2/s. 在100 ℃时复合膜的质子传导率达到0.074 S/cm, 高于SPAEKS膜的0.066 S/cm.  相似文献   

2.
本文报道了两种不同类型的聚(烯烃砜),即聚(环己烯砜)和聚(苯乙烯砜),并对它们进行了物理表征,给出了元素分析、红外光谱、核磁分析、凝胶渗透色谱及热重分析等的测试数据。用聚(环己烯砜)和聚(苯乙烯砜)作为抗蚀剂,其曝光特性:前者,灵敏度为5×10-6库仑/厘米2,分辨率为0.75微米,反差约1.5;后者分别为6×10-5库仑/厘米2,0.36微米及约2.5。尤为重要的是,聚(苯乙烯砜)具有优良的耐干法刻蚀的性能。聚(环己烯砜)作为强磁场聚焦电子照相记录材料,分辨率高于1.5微米。聚(苯乙烯砜)作为远紫外抗蚀剂,分辨率达0.5微米。  相似文献   

3.
建立了一种同时测定水产品中甲砜霉素和氟甲砜霉素药物残留的超高效液相色谱(UPLC)方法。样品经乙酸乙酯提取,正己烷液-液分配除脂,过HLB固相萃取小柱,用3mL10%甲醇淋洗,5mL100%甲醇洗脱,洗脱液用氮气吹干,残渣用1mL10%乙腈水溶液定容。采用超高效液相色谱分离,二极管阵列检测器检测,外标法定量。甲砜霉素在0.05~2.0mg/L,氟甲砜霉素在0.025~1.0mg/L范围线性关系良好,相关系数分别为0.9996、0.9999;样品加标平均回收率分别为80.0%、95.8%;相对标准偏差分别为5.6%、11.2%,甲砜霉素、氟甲砜霉素检出限分别为10μg/kg、5μg/kg。  相似文献   

4.
制备了基于磺化聚芳醚砜(SPAES)及聚醚砜(PES)的填充型复合质子交换膜, 研究了其吸水率、 尺寸变化、 热-机械特性、 质子电导率、 甲醇透过性及稳定性等性能. 通过浸入沉淀相转化法, 采用磺化度分别为30%(S30), 40%(S40)及50%(S50)的SPAES与PES制备了系列微孔型复合质子交换膜 Sx-y(x为SPAES的磺化度, y为SPAES的质量分数); 然后利用真空抽滤法在微孔中填充S50制备了相应的填充型复合质子交换膜Sx-y+F50. 结果表明, 由于微孔的引入及皮层结构的存在, Sx-y膜在低离子交换容量(IEC)条件下仍具有较高的电导率、 优良的机械强度、 优异的化学稳定性及较低的甲醇透过性. 经S50填充后, Sx-y+F50膜的IEC及电导率明显提升, 甲醇透过率大幅下降, 但机械强度及化学稳定性未见劣化. 其中S30-40+F50膜(IEC=0.69 mmol/g)的综合性能最佳, 其质子电导率在90 ℃水中达到50.4 mS/cm; 经140 ℃水处理24 h后失重率仅为8.2%, 质子电导率降低仅9%; 经过芬顿试剂(3% H2O2, 20 mg/L FeSO4, 80 ℃, 1 h)处理后失重率仅为0.66%; 甲醇透过率仅为6.8×10-8 cm2/s.  相似文献   

5.
马先蒿属植物苯丙素甙成分研究(Ⅰ)   总被引:1,自引:0,他引:1  
近年来,由苯丙素和糖组成的苯丙素甙由于具有药理活性而受到人们的重视[1~4].本文报道从穗花马先蒿(Pedicularis spicata)中分得的2个新苯丙素甙,马先蒿甙G(1)和H(2).  相似文献   

6.
将配体吡啶-2,6-二[N-(1′-咪唑基丙基)甲酰胺](L)与苦味酸稀土盐[RE(pic)-3]在甲醇中反应合成了9种吡啶-2,6-二[N-(1′-咪唑基丙基)甲酰胺\]稀土配合物,其结构经元素分析、红外光谱及紫外光谱表征,确定了配合物的结构为REL(pic)3·nCH3OH·H2O(RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Er; n=1或2; pic为苦味酸根)。并采用紫外光谱研究了游离配体对金属离子的识别性能。结果显示:加入稀土金属离子后,L中216 nm处吸收峰消失,202 nm处吸收峰明显增强且红移至213~218 nm处,表明配体对稀土金属离子具有明显的识别能力。  相似文献   

7.
荧光素衍生物稀土配合物的电学性质   总被引:1,自引:0,他引:1  
某些荧光素衍生物及其稀土配合物的电学性质及结构在文献中曾做了报道。为了探讨引入不同的取代基对配合物电学性质的影响,本文报道了曙红B(二溴二硝基荧光素二钠盐)、虎红(四氯四碘荧光素二钠盐)、荧光桃红(二氯四溴荧光素二钾盐)及其与La(Ⅲ)、Ce(Ⅲ)、Gd(Ⅲ)、Y(Ⅲ)稀土配合物的电阻率与温度变化的依赖关系。 1.配合物的制备 曙红B、虎红、荧光桃红均为上海化学试剂厂化学纯产品,经纯化后使用。氯化稀土(RECl_3·XH_2O)由相应的稀土氯化物溶于稀盐酸后转化而成。 曙红B用甲醇溶解,虎红和荧光桃红用蒸馏水溶解,分别配成0.05M溶液。将上述溶液按荧光素衍生物与RECl_3·XH_2O的摩尔比为3:1的量,分别逐滴加入含有稀土氯化物的  相似文献   

8.
稀土离子跨人血红细胞膜的荧光法研究   总被引:2,自引:0,他引:2  
采用Fura-2荧光浓度指示剂对红细胞的稀土跨膜作用进行了系列研究.结果表明,稀土离子不能通过完整的红细胞膜进入细胞内.通过与离子载体实验相对照,发现细胞ATP耗竭后,低浓度的稀土离子(5×10-6mol/L)不能跨膜进入ATP-耗竭红细胞.KCl去极化及加入电压依赖性钙通道刺激剂Bay-K8644对稀土离子的跨膜也没有促进作用.在Ca2+内流正常的情况下,低浓度稀土离子(5×10-6mol/L)对钙离子内流无影响.增大稀土离子浓度到5×10-4mol/L,用显微镜观察此时红细胞已开始溶血.在模拟胞内离子组分的缓冲液中(pH=7.05),比较了La3+,Eu3+和Ca2+对Fura-2的敏感程度.此条件下Fura-2对La3+和Eu3+的检测限分别为10-12和10-14mol/L,对Ca2+的检测限为10-8mol/L,并测得Fura-2-La3+(Eu3+)的络合比为1∶1,表观离解常数为1.7×10-12和4.95×10-14mol/L,表明用此法检测稀土离子跨膜行为相当灵敏有效.  相似文献   

9.
薛鹏  张聖晗  张翼  王吉德 《化学通报》2017,80(3):273-277
本文以组装性能良好的苯丙氨酸二肽(FF)为母体分子,用组氨酸对其进行化学修饰,通过多肽固相合成法合成了组氨酸-苯丙二肽(HisFF)凝胶因子。合成的HisFF分子通过质谱(MS)、核磁共振(NMR)和液相色谱(HPLC)方法测试确定精确的结构和纯度。HisFF聚集体的形貌结构通过透射电子显微镜(TEM)和扫描电子显微镜(SEM)观察。HisFF分子在甲苯、氯仿和乙酸乙酯溶剂中形成凝胶强度不同,TEM实验结果表明纤维强度和聚集形态影响其凝胶的强度。组氨酸-苯丙二肽在多种溶剂中,通过不同组装方法可以组装成各种各样的纳米结构。例如,HisFF在丙酮、甲醇和乙酸乙酯溶剂中可组装成纳米颗粒、纳米管和螺旋状纳米纤维;组氨酸-苯丙二肽先经HFIP溶解再通过溶剂稀释后,可得到不同直径的纳米纤维。但是在四氢呋喃、乙醇和乙腈溶剂中,两种方法组装的形貌几乎无变化。  相似文献   

10.
制备了窄分布的含酞侧基聚芳醚砜(PES-C)级份样品,用光散射法测定样品重均分子量,粘度法测定样品在DMF、CHCl3和1,2-C2H4Cl2中的特性粘数和Huggins参数k'值。k'值远大于0.5反映了体系中存在特殊的溶解行为。得到PES-C在3种溶剂中的Mark-Houwink方程: [η]=2.79× 10-2Mw0.615,r=0.999 8(DMF,25℃) [η]=3.96× 10-2Mw0.58,r=0.999 5(CHCl3,25℃) [η]=7.40× 10-2Mw0.52,r=0.999 5(1,2-C2H4Cl2,25℃).  相似文献   

11.
在甲醇介质中合成了15种新的磺胺甲氧哒嗪稀土配合物,对它们进行了元素分析、红外光谱、热谱和电导测定,部分配合物还做了X-射线粉末衍射和1HNMR鉴定。  相似文献   

12.
Transition metal coordination compounds with the novel N2S2-donor ligand 1,6-bis(4(5)-imidazolyl)-2,5-dithiahexane (abbreviated bhdhx) with general formulae M(bhdhx)(NO3)2(M = Co, Ni, Cu) and M(bhdhx)(H2O)2(BF4)2 (M = Cu, Zn) have been isolated. In all compounds the ligand is tetradentate with both thioether sulphurs and imidazole nitrogens coordinating. In all compounds the metal ions are six-coordinated in a distorted octahedral geometry with either nitrates or water molecules as the fifth and sixth ligands. This is confirmed by the ligand field spectra, which agree with a distorted octahedral coordination. The distortion from octahedral, indicated by the ligand field spectrum of the cobalt nitrate compound is such that the S atoms of the ligands must be at a very large distance from the metal ion. A single crystal of Cu(bhdhx)(NO3)2 was used in a structure determination: orthorhombic space group Pbcn, a = 14.351(5), b = 8.554(3), c = 13.057(4) Å, Z = 4, and T = 293 K. The structure was solved by heavy atom techniques and refined by least-squares methods to a residual R value of 0.033 for 847 significant reflections. The copper ion is at a special position on a two-fold axis, which causes a two-fold symmetry in the ligand. The coordination geometry of the copper atom is distorted octahedral with the two nitrates and the two thioether sulphurs in a cis position, and the imidazole nitrogens trans. The copper to nitrogen distances are 1.933(4) Å, the copper to sulphur distances are 2.495(1) Å, and the copper to oxygen distances are 2.280(3) Å.  相似文献   

13.
通过测定Rf值对比研究了二茂铁亚胺及其环汞化合物的色谱亲和性,发现环汞化合物比未汞化的二茂铁亚胺具有较高的Rf值,并用N→Hg分子内配位作用给予解释。分析取代基效应表明,亚胺氮上电子密度越高,Rf值越小。紫外可见光谱表明,环汞化合物分子中存在有N→Hg分子内配位作用。研究了N-Ar环和亚胺碳上的取代基效应对紫外光谱的影响,与N-Ar环上无取代基时相比,π→π*CT跃迁带的最大吸收波长移动值△λmax和Hammett-Brown常数σ+之间存在良好的线性关系。考察了二茂铁红外光谱规则对所研究体系的适用情况。  相似文献   

14.
通过水热方法合成了2个由多铌酸盐和过渡金属配合物形成的有机-无机杂化配合物[Cu(TETA)]4[VNb12(VO)4O40][OH]·10H2O(1)和[Cu(TETA)]4[VNb12(VO)6O40][OH]5·5H2O(2)(TETA=三亚乙基四胺). 化合物1和2的多阴离子分别是由4个{VO5}帽和6个{VO5}帽加盖在Keggin型多铌酸盐的方形缺口上形成的, 它们通过多酸阴离子中Nb-Ot (Ot =端氧)与[Cu(TETA)]2+配合物的金属中心配位构筑形成三维结构. 价键计算结果表明, Keggin中心的钒为+5价, 帽位的钒为+4价, X射线光电子能谱分析(XPS)结果也证实了这一结论. 通过单晶X射线衍射分析、红外光谱(IR)、粉末X射线衍射(PXRD)、热重(TG)分析和元素分析对这2个化合物的结构和性质进行了表征.  相似文献   

15.
合成了13种1,5-双(1′-苯基-3′-甲基-5′-吡唑啉酮-4′)-戊二酮-[1,5](BPMPPD)和溴化十六烷基吡啶盐(CPB)的稀土配合物.研究了配合物的红外光谱、紫外可见光谱、差热-热重谱、荧光光谱、核磁共振谱及摩尔电导等性质,发现配合物属离子型缔合物CP+[Ln(BPMPPD)2]-.Pr、Nd、Ho、Er、Tm配合物发生超灵敏跃迁.配合物的热分解温度具有"四分组"效应,Sm、Eu、Tb、Oy为线性荧光。  相似文献   

16.
The dinuclear complex [Co2(μ-OAc)2(OAc)2(μ-H2O)(phen)2] has been prepared and its structure was determined. The compound crystallizes in the monoclinic space group P2(1)/c. The Co–Co distance is 3.574 Å and is similar to the Fe–Fe distance in the reduced methane monooxygenase hydroxylase. The electronic and IR spectra of the complex confirm octahedral coordination of the cobalt atoms and formation of strong O–HO hydrogen bonds in the solid state. The dependence of the magnetic susceptibility of the complex on temperature indicates an antiferromagnetic interaction, the value of the isotropic exchange parameter J was estimated to be −2.1 cm−1. The 1H NMR spectra show that in organic solvents the structure of compound is the same as in the solid state, however, in water solution the complex dissociates giving compounds with different Co:phen ratios.  相似文献   

17.
Mössbauer absorption spectra of rare-gas matrix-isolated SnX4 and SnX2 molecules (X = F, Cl, Br, I) have been measured at matrix temperatures of a bout 5 K. The hyperfine interaction (hfi) parameters of 119Sn in argon matrix-isolated SnX4 (X = Cl, Br, 1) molecules are identical with those of the corresponding crystalline compounds. This fact reveals that the inter-molecular interactions are negligible in the crystalline compounds as far as concerning the electronic structure of Sn4+. The 119Sn hfi parameters of rare-gas matrix-isolated SnX2 molecules differ from those measured in the crystallin compounds. This arise from the totally different coordination of tin in the two situations. The analysis of the hfi parameters using a simple bonding model yields information about the ionicity of the Sn-halogen bonds and the bonding angle in these molecules. The observed isomer shifts and quadrupole interactions can only be explained in this model with a bonding angle θ = 95° ± 2° for all SnX2 molecules and a slight increase of θ from Sn12 to SnF2.  相似文献   

18.
X-ray absorption spectra at the chromium K-edge are reported for a number of selected chromium compounds of known chemical structure. The spectra were obtained with use of synchrotron radiation available at the ectron tretcher ccelerator ELSA in Bonn. The compounds studied include the tetrahedrally coordinated compounds Ca2Ge0.8Cr0.2O4, Ba2Ge0.1Cr0.9O4, Sr2CrO4, Ca2(PO4)x(CrO4)1−xCl (x=0.25,0.5), Ca5(CrO4)3Cl, CrO3, the octahedrally coordinated compounds Cr(II)-acetate, CrCl3, CrF3, Cr2O3, KCr(SO4)2 · 12H2O, CrO2 and cubic coordinated metallic chromium. In these compounds chromium exhibits a wide range of formal oxidation states (0 to VI). The absorption features in the near edge region are shown to be characteristic of the spatial environment of the absorbing atom. The occurrence of a single pre-edge line easily allows one to distinguish between tetrahedral and octahedral coordination geometry, whereas the energy position of the absorption edge is found to be very sensitive to the valency of the excited chromium atom. Calculations of the ionisation potential of Cr in different oxidation states using the non-relativistic Hartree–Fock method (Froese–Fischer) confirm that the ionisation limit shifts to higher energy with increasing Cr valency. More detailed information on the electronic structure of the different compounds is gained by real-space full multiple scattering calculations using the FEFF8 code.  相似文献   

19.
The spirocyclic silylamides M[(NR)2SiMe2]2 (R = t-Bu: M = Hf (III), V (IV); R = SiMe3: M = V (V), NbCl (VI), TaCl (VII)) have been prepared by reaction of the HfCl4, VCl4, NbCl5 and TaCl5, respectively, with Me2Si[N(Li)R]2. Methylation of VI and VII with MeLi yields the respective NbCH3 and TaCH3 derivatives (VIII and IX). The effective magnetic moments of IV and V are 1.67 and 1.66 μB respectively. Infrared and Raman spectra are given, and the 1H, 13C and 29Si chemical shifts for the diamagnetic compounds are reported. Single-crystal X-ray studies have been performed on III, IV and VIII. The structures of III and IV possess distorted tetrahedral symmetry (D2d), with mean M---N distance of 2.030(4) and 1.853(5) Å, respectively. Distorted trigonal-bipyramidal coordination with an equatorial methyl group is found for each Nb atom of the two crystallographically independent molecules of VIII. Mean Nb---C, Nb---N (equatorial) and Nb---N (axial) bond lengths are 2.218(9), 1.997(4) and 2.026(5) Å, respectively.  相似文献   

20.
二环戊二烯基二氯化钛与脂肪醇的反应是非常复杂的,由于反应体系不同,所得的产物也不同,且产物又不稳定[1-3]。  相似文献   

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