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PF—吐温—80分光光度法测定钼的方法研究 总被引:3,自引:0,他引:3
在0.05-0.4mol.L^-1盐酸溶液中,吐温-80存在下,钼与苯基萤光酮生成橙色配合物,在该配合物的第二吸收峰测量,其表观摩尔吸光系数ε=1.1×10^4L.mol^-1.cm^-1,测得配合物组成比为Mo=PF=1:1。在25mL溶液中含钼0-8μg范围时遵守比耳定律。有色配合的稳定6h以上。此法用于矿石中微量钼的测定,结果令人满意。 相似文献
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DBC-偶氮胂对铋的灵敏度较高且选择性好,在0.2-1.0mol/L硝酸介质中与Bi形成配位比为1:2的紫红色配合物,λmax=630nm,ε630=8.8×10^4L.mol^-1.cm^-1。铋量在0-=10μg/10mL范围内符合比耳定律。用于人发中微量的铋的测定,操作简便,结果满意。 相似文献
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苯基荧光酮在混合表面活性剂体系中铜、铝的分光光度法同时测定 总被引:3,自引:1,他引:2
本文对在溴代十六烷基三甲铵和吐温80混合表面活性剂中苯基荧光酮分光光度法同时测定铜和铝进行了研究。实验表明,在磷酸介质中,pH=6.8-7.4范围内,苯基荧光酮与铜、铝形成稳定的络合物。铜络合物最大吸收波长为600nm,εCu600=6.63×104L·mol-1·cm-1,线性范围为0—5μg/25mL;铝络合物最大吸收波长为564nm,εAl564=1.01×105L·mol-1·cm-1,线性范围0—6μg/25mL。方法灵敏度高,选择性好,用于水及健康人体冻干血浆中铜、铝回收率的测定,结果满意。 相似文献
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2—溴甲基萘荧光和室温磷光性质研究 总被引:3,自引:3,他引:0
研究了2-溴甲基萘(2-BrMN)的荧光及磷光性质。2-溴甲基萘是一种优良的荧光试剂,λex/λem=274/334nm,其浓度在1.0×10^-6~1.2×10^-4mol·L^-1范围内与荧光强度呈良好的线性关系,相关系数r=0.999,最低检测限为4.7×10^-8mol·L^-1。以β-环糊精(β-CD)作保护剂和1,2-二溴丙烷(DBP)为重原子微扰剂的2-BrMN/β-CD/DBP体系 相似文献
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卡托普利测定新方法的研究 总被引:8,自引:1,他引:7
马卫兴 《光谱学与光谱分析》1999,19(1):118-119
基于卡托普利将Co^2+的为Cu,新生的Cu可一新铜试剂形成黄色络合物,提出了间接分光度法法测定药物中卡托利析新方法。在PH3-8内,卡托普利浓度在0-28μg/mL内有从比耳定律,测定的表观摩尔吸光系数ε为8.13×10^3L·mol^-1·cm^-1。方法简便、快速,用地药物中卡托普利的测定,结果与钨蓝比色法一致。 相似文献
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合成了一种新配体N,N-二[(二苯基膦)甲基]-2-吡啶胺(L)及其双核铜(Ⅰ)配合物(CuBrL)2(1),采用1HNMR、吸收光谱、质谱和元素分析等方法对化合物进行表征,并通过X射线单晶衍射确定配合物1的晶体结构。该晶体结构属三斜晶系,P-1空间点群。配合物1是中心对称的双核Cu(Ⅰ)配合物,中心离子Cu(Ⅰ)采取扭曲四面体空间构型,分别与配体L的两个P原子和两个桥联的Br原子配位;其中Cu-Cu距离为0.3060nm,大于两个铜原子的范德华半径之和,因此不存在Cu-Cu相互作用。密度泛函理论(DFT)计算表明1的HOMO电子密度主要集中于铜和卤素原子,而LUMO电子密度分布在配体(L)上。研究工作表明,配合物1的最低能级激发态通过金属到配体电荷跃迁(MLCT)和卤素到配体的电荷跃迁(XLCT)两种机制形成。 相似文献
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2-(2-喹啉偶氮)-1,5-苯二酚光度法测定铜的研究 总被引:11,自引:2,他引:9
合成了新试剂 2 - ( 2 -喹啉偶氮 ) - 1,5-苯二酚 ( QADHB) ,并研究了其与铜的显色反应 ,在溴化十六烷基三甲胺 ( CTMAB)存在下 ,p H=4 .0邻苯二甲酸氢钾缓冲介质中 ,QADHB与铜反应生成 2∶ 1稳定络合物 ,λmax=540 nm,ε=2 .12× 10 4 L·mol-1·cm-1。铜含量在 0— 30 μg/ 2 5m L内符合比耳定律 ,该方法用于环境样品中铜的测定 ,结果令人满意 相似文献
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研究了新显色剂3,5-二(1-羧基-4,5-二甲氧基-2-苯氨基偶氮基)苯甲酸(CDMOBAABA)与铜(Ⅱ)的显色反应。在TritonX-100存在下,于pH9.5的NH3-NH4Cl缓冲介质中,CDMOBAABA与铜(Ⅱ)形成棕红色配合物。试剂与络合物的最大吸收波长分别为450nm和540nm。表观摩尔吸光系数为2.43×105L·mol-1.cm-1。铜(Ⅱ)含量在0—20μg/25mL范围内符合比耳定律。该方法用于铝合金样品中铜的测定,结果与原子吸收光谱法相吻合,相对标准偏差1.89%。 相似文献
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Both reductive and oxidatlve mode of metabolism have been hypothesized for the antitumor agent mitoxantrone. This work aims to better understand the redox properties of mitoxantrone in the presence of the physiological redox couple, copper(I)/copper(II), by means of polarograpy and spectrophotometry. The first quasi-reversible one-electron reduction of mitoxantrone to the semiquinone and the second reduction to the hydroquinone have been shown to be considerably affected by copper. Visible spectra of mitoxantrone-copper mixtures in nitrogen and oxygen purged solutions taken in a one-week period exhibit varying degrees of complexation and oxido-reduction. When copper(II), neocuprolne and mitoxantrone are mixed in a certain ratio in pH 7. 4 phosphate buffer solution, two new peaks at 584 and 632 nm emerge in the spectra indicating a ternary charge transfer complex. The complex atoichiometry was established as Cu(IT): neocuproine: tritoxan-trone = 2:4:1 by Job's method of continuous variations. The ternary complex is sensitive to the relative concentrations of mitoxantrone and copper(II), an excess of the latter giving rise to complete red ox products. This complex may be important in modeling the drug's oxidative mode of ant tumor action. 相似文献
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Anna Lähde Noora Kokkonen Antti J. Karttunen Sirpa Jääskeläinen Unto Tapper Tapani A. Pakkanen Jorma Jokiniemi 《Journal of nanoparticle research》2011,13(9):3591-3598
Atmospheric pressure chemical vapor synthesis was used to produce copper nanoparticle composites in an amorphous silicon dioxide,
i.e., either copper nanoparticles coated with amorphous silicon dioxide or copper nanoparticles embedded in amorphous silicon
dioxide matrix. Synthesized metal–organic copper(I) complex was used as a precursor that provided well-defined ratio (1:2)
of copper and silicon. The thermal decomposition of the Cu(I) complex molecule leads to homogenous nucleation and formation
of copper nanoparticles which are subsequently coated with Si/SiO2 in the gas phase. The decomposition was greatly enhanced when reductive atmosphere, i.e., H2/N2 10 v% were used instead of pure nitrogen. A narrow size distribution with the geometric mean diameter of the particle agglomerates
around 30 nm was observed while the primary size of the copper core particles was around 5 nm. 相似文献
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The X-ray K-absorption spectra of copper in some of its complexes involving ligands like penicillamine (known detoxicating agent for heavy metal poisoning) and cysteamine (a known radiation protector) have been investigated using a 40 cm curved crystal spectograph. These complexes are described in the literature as being mixed-valence [1, 2]. The copper-penicillamine complex shows two distinct edges, K1 and K2, indicating mixed-valency in the complex. The cysteamine complexes do not show any splitting of the edges. In one of the cysteamine complexes, which is said to involve molecular oxygen, the magnitudes of shifts of the main edge and principal absorption maximum fall close to copper (II) compounds whereas in the other complex, these shifts are in the range of copper (I) compounds. The probable reasons for the observed deviations have been discussed. 相似文献
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Debarati Dey 《Journal of luminescence》2011,131(4):732-738
The photoinduced electron transfer (PET) reaction within a ternary copper complex [Cu(phen)(Htrp)]+ (Htrp: l-tryptophanato; phen: 1,10-phenanthroline) (1) and in presence of DNA has been studied in homogeneous buffer medium and in reverse micelles. An intramolecular electron transfer occurs within the photoexcited complex (1) from tryptophan to phen. The copper complex can displace ethidium bromide from DNA backbone and on photoexcitation can oxidize DNA in a deoxygenated environment due to intermolecular electron transfer, although the intramolecular electron transfer is thermodynamically favorable. A prominent magnetic field effect (MFE) has been found even in homogeneous aqueous medium for the triplet born radicals both in case of intra and intermolecular electron transfer reactions. In case of intramolecular electron transfer the observation of MFE is similar to that of linked donor-acceptor system. However the observation of MFE for the intermolecular electron transfer between non-covalently bound complex-DNA systems is rather rare. Some non-covalent weak interaction, e.g. hydrophobic interaction between the phen ligand and DNA base pairs and electrostatic force of attraction between [Cu(phen)(Htrp)]+ complex and DNA may lead to partial intercalation of the copper complex within DNA that is responsible for such a rare observation. 相似文献
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N. E. Domracheva A. Mirea M. Schwoerer L. Torre-Lorente G. Lattermann 《Physics of the Solid State》2007,49(7):1392-1402
New nanostructured materials, namely, the liquid-crystalline copper(II) complexes that contain poly(propylene imine) dendrimer ligands of the first (ligand 1) and second (ligand 2) generations and which have a columnar mesophase and different copper contents (x = Cu/L), are investigated by EPR spectroscopy. The influence of water molecules and nitrate counterions on the magnetic properties of complex 2 (x = 7.3) is studied. It is demonstrated that water molecules can extract some of the copper ions from dendrimer complexes and form hexaaqua copper complexes with free ions. The dimer spectra of fully hydrated complex 2 (x = 7.3) are observed at temperatures T < 10 K. For this complex, the structure is identified and the distance between the copper ions is determined. It is shown that the nitrate counterion plays the role of a bridge between the hexaaqua copper(II) complex and the dendrimer copper(II) complex. The temperature-induced valence tautomerism attended by electron transport is revealed for the first time in blue dendrimer complexes 1 (x = 1.9) with a dimer structure. The activation energy for electron transport is estimated to be 0.35 meV. The coordination of the copper ion site (NO4) and the structural arrangement of green complexes 1 (x = 1.9) in the columnar mesophase are determined. Complexes of this type form linear chains in which nitrate counterions serve as bridges between copper centers. It is revealed that green complexes 1 (x = 1.9) dissolved in isotropic inert solvents can be oriented in the magnetic field (B 0 = 8000 G). The degree of orientation of these complexes is rather high (S z = 0.76) and close to that of systems with a complete ordering (S z = 1) in the magnetic field. Copper(0) nanoclusters prepared by reduction of complex 2 (x = 7.3) in two reducing agents (NaBH4, N2H4 · H2O) are examined. A model is proposed for a possible location of Cu(0) nanoclusters in a dendrimer matrix. 相似文献
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析相光度法测定铁(Ⅲ)的研究 总被引:2,自引:0,他引:2
本研究了铁(Ⅲ)-PEG(聚乙二醇-2000)-铬锖R-Na2SO4体系的上光度法并应用于测定Fe(Ⅲ)。最适酸并为4.5 ̄6.5(NaAc-HAc)缓冲溶液,其络合物的最大吸收位于560nm,表观摩尔吸光系数为5.36×10^4L·mol^-1·cm^-1,Fe(Ⅲ)浓度在0 ̄4μg范围内服从比尔定律,铁与铬菁R形成组成为1:2的稳定络合物。该方法用于蔡叶中铁的测定,获得了满意的结果。 相似文献