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1.
反相高效液相色谱同时测定复方降压药中三组分   总被引:2,自引:0,他引:2  
建立了一种反相高效液相色谱法 ,用于同时测定复方降压药中三组分。采用YWGC1 8柱 ,以甲醇 醋酸 醋酸钠缓冲液 水 ( 60∶2 0∶2 0 )为流动相 ,流速为 0 .8mL·min- 1 ,二极管阵列检测器于检测波长 2 60nm测定。硫酸双肼酞嗪、氢氯噻嗪和氨苯喋啶的线性范围分别为 0 .0 8~ 1 .1mg/mL ,0 .0 1~ 0 .30mg/mL ,0 0 3~ 0 .45mg/mL ,检测限分别为 0 0 0 6mg/mL ,0 0 0 1mg/mL ,0 0 0 1mg/mL ,已用于北京降压0号样品的测定  相似文献   
2.
A novel method for the selective electromembrane extraction (EME) of U6+ prior to fluorometric determination has been proposed. The effect of extraction conditions including supported liquid membrane (SLM) composition, extraction time and extraction voltage were investigated. An SLM composition of 1% di-2-ethyl hexyl phosphonic acid in nitrophenyl octyl ether (NPOE) showed good selectivity, recovery and enrichment factor. The best performance was achieved at an extraction potential of 80 volts and an extraction time of 14 minutes Under the optimized conditions, a linear range from 1 to 1000 ng mL−1 and LOD of 0.1 ng mL−1 were obtained for the determination of U6+. The EME method showed good performance in sample cleanup and the reduction of the interfering effects of Mn2+, Zn2+, Cd2+, Ni2+, Fe3+, Co2+, Cu2+, Cl and PO43− ions during fluorometric determination of uranium in real water samples. The recoveries above 54% and enrichment factors above 64.7 were obtained by the proposed method for real sample analysis.  相似文献   
3.
The TbIII compound [Tb(tci)(H2O)]n · n(DMF) ( 1 ) [H3tci = tri(2‐carboxythyl)isocyanurate, DMF = N,N′‐dimethylformamide] was synthesized by the reaction of terbium oxide, H3tci, and two drops of concentrated nitric acid in the presence of DMF and H2O. Single crystal X‐ray analysis reveals that it features a three‐dimensional (3D) framework based on infinite –Tb–COO–Tb– chains. The tci ligand in 1 links six different TbIII ions with its two carboxylate groups in μ2‐κ1O;κ2O,O′ mode and the third in μ2‐κ1O;κ1O′ mode. Thermal analysis reveals that it remains high thermal stability until 390 °C. Luminescence investigation shows that it emits characteristic green light of TbIII ions.  相似文献   
4.
Co3xNi3−3x(PO4)2·8H2O (x = 1, 0.8, 0.6, 0.4, 0.2, and 0) were synthesized via simple wet chemical reaction and energy saving route method. The final decomposition products of hydrates are corresponding anhydrous tri(cobalt nickel) diphosphates. The metal and water contents of the synthesized hydrates were confirmed by AAS and TG/DTG/DTA techniques, respectively. The observed metal and water contents agree well with the formula of the title compounds. The crystal structures and lattice parameters as well as crystallite sizes of the studied compounds were determined using XRD data. The results from XRD and TG/DTG/DTA techniques confirmed that Co3xNi3−3x(PO4)2·8H2O at all ratios were the single phase. The FTIR spectra of studied compounds were recorded and assigned. The thermal behaviours of single and binary tri(cobalt nickel) diphosphate octahydrates were studied for the first time. The morphologies of the studied compounds were investigated by using the SEM technique. The micrographs of all studied compounds exhibited the thin plated morphology. The surface area and the pore size data of anhydrous forms were measured by N2 adsorption at −190 °C according to the BET method. The anhydrous forms of binary metal phosphate at x = 0.8, Co2.4Ni0.6(PO4)2, exhibits the highest surface area and expects to improve the catalytic activity.  相似文献   
5.
提出了利用双波长分光光度法测定三辛胺(TOA)及三辛胺盐酸盐(TOA·HCl)的一种新方法,即TOA和TOA·HCl在CCl4溶液中与I2生成电荷转移化合物,其最大吸收波长分别为293nm和263nm,两组分同时存在时可利用吸光度的加和性得联立方程,分别求出两组分的含量。TOA含量在0~35mg/L,TOA·HCl含量在0~31mg/L范围内符合比耳定律。该法简便快速,方法的回收率为95.5%~104.6%,能够满足分析的需要  相似文献   
6.
We synthesized melemium hydrogensulfate H3C6N7(NH2)3(HSO4)3 by reaction of melem with 70 % sulfuric acid. The crystal structure was elucidated by single‐crystal XRD (P21/n (no. 14), Z = 4, a = 10.277(2), b = 14.921(3), c = 11.771(2) Å, β = 99.24(3)°, V = 1781.5(6) Å3). H3C6N7(NH2)3(HSO4)3 is the first compound displaying a triple protonation of melem., In this contribution an overview of accessible melemium sulfates depending on the concentration of sulfuric acid is given. Two additional melemium sulfates were identified this way.  相似文献   
7.
Tri(mesityloxy)silanethiol (TMST) was isolated as the only product of the reaction between SiS2 and 2,4,6‐trimethylphenol. TMST crystallizes in the triclinic system. Good quality of the crystal allowed the unrestricted refinement of the mercapto group; the resulting S–H distance is 1.29(4) Å and the Si–S–H bond angle is 95.4(17)°. Molecules of TMST show no hydrogen bonds in the crystal – the FT‐IR spectrum of the solid sample exhibits a very sharp, well‐resolved band of isolated –SH group at 2562 cm–1.  相似文献   
8.
Abstract

A luminescent cadmium(II) metal-organic framework, [Cd(tppa)2 (bpdc)2]n (1) (tppa?=?tri(4-pyridylphenyl)amine, bpdc =4,4′-biphenyldicarboxylic acid), has been solvothermally synthesized by using Cd(NO3)2·4H2O and a mixture of tppa and bpdc. Single crystal X-ray analysis reveals that 1 crystallizes in the orthorhombic system and Pbcn space group. Its overall structure is a twofold interpenetrated framework, and it shows a porosity of 31.8% based on a calculation by PLATON and a 4-c type topological network with the point symbol of {6^5.8}. In addition, 1 may be exploited as WLED due to its ability to give off yellow light under ultraviolet excitation.  相似文献   
9.
Two nickel(II) coordination polymers, namely, {[Ni1/2(TPO)1/3(bib)1/2(H2O)] · H2O}n ( 1 ), and [Ni(HTPO)(bpy)(H2O)2]n ( 2 ), were assembled from tripodal ligand of tripodal tri(p‐carboxyphenyl) phosphane oxide (H3TPO) and two N‐donors [bib = 1,4‐bis(imidazolyl)benzene, and bpy = 4,4′‐bipyridine]. Their structures were determined by single‐crystal X‐ray diffraction analysis and further characterized by elemental analysis, IR spectra, powder X‐ray diffraction (PXRD), and thermogravimetric analysis (TGA). Structural analysis reveals that complex 1 is an interestingly 3D (3,4)‐connected {103}2{106}3 net, whereas complex 2 is a 1D polymeric chain, which was further expanded into a 3D supramolecular structure through hydrogen bonds. Luminescent sensing measurements show two nickel CPs can selectively and sensitively detect for acetone from normal solvents (DMF, DMA, DMSO, MeOH, EtOH, CH3CN, H2O, and N‐butanol).  相似文献   
10.
Calcium hydrogenmelonate heptahydrate Ca[HC6N7(NCN)3] · 7H2O was obtained by metathesis reaction in aqueous solution. The structure of the molecular salt was elucidated by single‐crystal X‐ray diffraction. The crystal structure consists of alternating layers of planar monopronated melonate ions, Ca2+ and crystal water molecules. The anions of adjacent layers are staggered so that no π–π stacking occurs. The melonate entities are interconnected by hydrogen bonds within and between the layers. Ca[HC6N7(NCN)3] · 7H2O was investigated by solid‐state NMR and FTIR spectroscopy, TG and DTA measurements.  相似文献   
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