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1.
通过静态和动态实验,研究了CL-7402萃淋树脂吸附铅的性能和减压微色谱柱分离富集铅的最佳条件。实验表明,此萃淋树脂吸附快,吸附容量大。在减压条件下,以1mol/LHBr为上柱介质,2mol/LHNO3为洗脱液,可使铅与铜、铁等金属离子快速分离。采用三溴偶氮胂光度法测定样品中的铅。  相似文献   

2.
对铁和稀土元素在DOWEX 1-X8阴离子交换树脂上于不同浓度的盐酸和硝酸介质中的分配系数(K_d)进行了研究,试验结果表明:在6~9 mol·L~(-1)盐酸介质中Fe~(3+)的K_d10~3,即强吸附于DOWEX 1-X8阴离子交换树脂,而稀土元素在DOWEX 1-X8阴离子交换树脂的K_d≤10,即不吸附于树脂;而在浓度低于2 mol·L~(-1)的硝酸介质中,Fe~(3+)的K_d6.4,即不吸附于树脂上,故选用1.6 mol·L~(-1)硝酸溶液将吸附于柱上的Fe~(3+)洗脱下来。在此基础上提出了一种阴离子交换树脂分离电感耦合等离子体原子发射光谱法测定洁净钢中微量稀土元素含量的方法。该方法用于测定产于日本及韩国的洁净钢样品,测得回收率在87.7%~118.3%之间,相对标准偏差(n=6)小于23%。  相似文献   

3.
研究TN503(N,N-二仲辛基乙酰胺)萃淋树脂在HCl体系中对铁的吸附性能。测定了 6mol/L HCl中 N503萃淋树脂对铁(Ⅲ)的吸附动力学,实验表明树脂吸附铁(Ⅲ)按准一级反应进行,并符合 Freundlich吸附等温式。根据吸附平衡的研究发现,N503萃淋树脂吸附铁(Ⅲ)的反应按下式进行: 2N503+H+FeCl4=(N503)2·H·Fecl4并用于盐酸中铁的分离测定。  相似文献   

4.
制备了高功能基转化率的孪二羟基树脂,由此合成了含亚硫酸乙烯酯功能基(2.30毫摩尔/克树脂)和碳酸乙烯酯功能基(2.57毫摩尔/克树脂)的树脂4和5。在酸度范围内树脂4选择吸附Pt(Ⅱ),两者对Au(Ⅲ) 有高选择吸附性,而很少吸附共存的Pd(Ⅱ)、Pt(Ⅳ)及铁、钴、镍、铜、锰、锌、铅、镉等二价金属离子。树脂4对金的吸附容量为126(毫克 Au(Ⅲ)/克树脂),分配系数Kd为824(毫升/克),一次洗脱率达85%。树脂5的吸附容量为46.0(毫克 Au(Ⅲ)/克树脂),Kd为84.1(毫升/克)。两种树脂吸附Au(Ⅲ)的速率T_(1/2)分别为1、0.8小时.  相似文献   

5.
研究TN503(N,N-二仲辛基已酰胺)草淋树脂在HCI体系中对铁的吸附性能。测定了6mol/LHCI中N503草淋树脂对铁(Ⅲ)的吸附动力学,实验表明树脂吸附铁(Ⅲ)按准一级反应进行,并符合Freundlich吸附等温式。根据吸附平衡的研究发现,N503萃淋树脂吸附铁(Ⅲ)的反应按下式进行:并用于盐酸中铁的分离测定。  相似文献   

6.
本文研究了Cyanex302萃淋树脂从硝酸介质中吸附重稀土(Ⅲ),吸附能力为Lu>Yb>Tm>Er>Ho>Dy>Tb>Gd。考察了平衡水相酸度、稀土浓度、温度等对吸附平衡的影响。计算了重稀土(Ⅲ)间的平均分离系数β~z+1_z=3.55,表明分离稀土(Ⅲ)的选择性优于HDEHP、HEH/EHP萃淋树脂,有可能用于制备高纯单一重稀土。Cyanex302萃淋树脂饱和吸附稀土(Ⅲ)的红外光谱表明,P=S键参与了配位。  相似文献   

7.
本文研究了异丙基膦酸单(1-己基-4-乙基)辛酯萃淋树脂在盐酸介质中对重稀土元素(Ⅲ)的吸萃平衡,考察了平衡水相酸度对吸附反应的影响,计算了重稀土(Ⅲ)间的平均分离系数,确定了吸附反应的Freudlich等温吸附方程。该树脂吸附Yb(Ⅲ)的静态饱和容量为66.5mgYb/(g.R),饱和萃合物的IR谱表明PT-2萃淋树脂吸附Yb(Ⅲ)的反应为阳离子交换反应。  相似文献   

8.
N263萃淋树脂的合成及其在金矿液分析中的应用   总被引:9,自引:0,他引:9  
合成了N_(263)萃淋树脂,并测定了该树脂的一些性能。用合成的N_(263)树脂分离、富集矿石中的金,在5%~20%王水介质中均可定量吸附。上柱流速2ml·min~(-1),以2.0%硫脲-1.0mol·L~(-1)盐酸作洗脱液,洗脱液流速0.5ml·L~(-1),用过氧化氢破坏硫脲后,硫代米蚩酮光度法测定金。金在10~200μg范围能定量回收,回收率达98%。方法选择性好,树脂可重复使用15次以上。  相似文献   

9.
TBP萃淋树脂微孔色谱柱分离富集钼的研究与应用   总被引:1,自引:0,他引:1  
提出了用减压高效微孔色谱柱分离富集矿石中痕量钼,并对TBP苹淋树脂微孔层析柱的性能进行了较为详细的研究.试验发现,在零空床体积下,以3.0mol·L~(-1)盐酸溶液(在抗坏血酸存在下)为介质上柱,0.5mol·L~(-1)盐酸1.2ml洗脱,可以实现钢与大量铁、钨、钒、钛、锡、锆、铀等共存元素的分离.与常规柱相比较,减压微孔层析柱具有柱效高,洗脱体积小,分离速度快等优点,并能节省大量试剂.方法经标准样品验证,结果满意.  相似文献   

10.
三正辛胺萃淋树脂的合成及对银分离富集的研究   总被引:1,自引:0,他引:1  
报道了Levextrel型三正辛胺(TOA)萃淋树脂的合成方法及对银分离富集的研究,用新合成的萃淋树脂,铅锌冶炼矿渣中的银在1mol/L的盐酸介质中定量吸附后可用0.25mol/L NH4Cl-0.5mol/L硫脲洗脱,以火焰原子吸收光谱法测定,其回收率为99.4%-104.3%。此树脂对浓度低至0.5μg/mL的银亦可富集和定量回收,并有较长的使用寿命。  相似文献   

11.
Rotational spectra of KrCuF and KrCuCl have been measured in the frequency range 8-18 GHz, using a pulsed jet cavity Fourier transform microwave spectrometer. The molecules were prepared by ablating Cu metal with a pulsed Nd:YAG laser (1064 nm) and allowing the plasma to react with appropriate precursors (Kr plus SF(6) or Cl(2)) contained in the backing gas of the jet (Ar or Kr). Rotational constants, internuclear distances, vibration frequencies, and (83)Kr, Cu, and Cl nuclear quadrupole coupling constants have all been evaluated. The Kr-Cu bonds are short and the complexes are rigid. The (83)Kr coupling constant of KrCuF is large (128.8 MHz). The Cu nuclear quadrupole coupling constants differ radically from those of uncomplexed CuF and CuCl molecules. The results are supported by those of ab initio calculations, which have also yielded Mulliken populations, MOLDEN plots of valence molecular orbitals and Laplace concentrations, and electron localization functions. The results are consistent with those reported earlier for other noble gas-noble metal halide complexes. The results have been used to assess the nature of the bonding in the complexes and have produced good evidence for weak noble gas-noble metal chemical bonding.  相似文献   

12.
The procedure for assigning names to elements by the International Union of Pure and Applied Chemistry involves establishing priority of discovery, then inviting the discoverers to suggest a name. This protocol is in contrast with the suggestions of Friedrich A. Paneth form 1947, who believed that the discoverers of an element have the undisputed right to name it. This difference in philosophy came to light during a workshop convened 10 years ago for the purpose of naming elements 104–109, when the discoverers of these elements contended that they were solely entitled to name them. During the debate, and in support of the name seaborgium for element 106, it was argued that gadolinium, samarium, gallium, einsteinium and fermium had been named after living scientists. The history of the naming of these elements demonstrates that this is not the case; Glenn T. Seaborg is the first scientist for whom an element was named during his lifetime.  相似文献   

13.
Immanuel Kant has built up a dualistic epistemology that seems to fit to the peculiarities of chemistry quite well. Friedrich Paneth used Kant’s concept and characterised simple and basic substances which refer to the empirical and to the transcendental world, respectively. This paper takes account of the Kantian influences in Paneth’s philosophy of chemistry, and discusses pertinent topics, like observables, atomism and realism.
Klaus RuthenbergEmail:
  相似文献   

14.
We Coulomb explode argon and neon dimers, trimers, and tetramers by multiple ionization in an ultrashort 800 nm laser pulse. By measuring all momentum vectors of the singly charged ions in coincidence, we determine the ground state nuclear wave function of the dimer, trimer, and tetramer. Furthermore we retrieve the bond angles of the trimer in position space by applying a classical numerical simulation. For the argon and neon trimer, we find a structure close to the equilateral triangle. The width of the distribution around the equilateral triangle is considerably wider for neon than for argon.  相似文献   

15.
Equilibrium structures and both harmonic and anharmonic stretching force constants have been calculated ab initio for the four cyanides HCN, LiCN, FCN, and C1CN, and the four isocyanides HNC, LiNC, FNC, and ClNC, using several basis sets of about triple-zeta quality. The CN and NC bond lengths, as well as diagonal stretching force constants, are nearly the same throughout both series. Trends in the off-diagonal stretching force constants are discussed, and dipole moment values are correlated with the structural type, XCN and XNC, and the electronegativity of the ligand X.  相似文献   

16.
Azo compounds and bistriazenes were obtained by diazo coupling of diazotized 5-amino-2-R-1,3,4-thiadiazoles; tetrazolo[4,5-b]-1,3,4-thiadiazoles, to which azido-tetrazole tautomerism is peculiar, were obtained by replacement of the diazo group by an azido group. The structures of the products were confirmed by their IR and UV spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 933–936, July, 1980.  相似文献   

17.
Evidence for unusual shapes of simple MX(n) molecules that are not stable under normal conditions is critically appraised in this review, which assesses current knowledge of the spectra and structures of many simple binary halides, oxides, and hydrides. It emphasizes the need for more high-resolution gas-phase spectroscopic data, summarizes the current state of knowledge in many fields, and suggests key experiments that should be carried out to resolve conflicting results obtained in earlier studies.  相似文献   

18.
The chemical and electrochemical syntheses of the zinc (I) and cadmium (II) complexes are carried out on the basis of the tridentate Schiff base (H2L), the condensation product of (2-tosylaminoaniline) N-(2-aminophenyl)-4-methylbenzenesulfunamide with 1-phenyl-3-methyl-4-formylpyrazole-5-thiol. The structures and compositions of the synthesized metallochelates are proved by the data of C, H, and N elemental analyses, IR spectroscopy, and 1H NMR spectroscopy. X-ray absorption spectroscopy is used to determine the structure of the zinc complex. The binuclear structure of the cadmium complex is confirmed by the X-ray diffraction data (CIF file CCDC no. 1471159). The optical properties of H2L and the zinc and cadmium complexes in dimethyl sulfoxide (DMSO) solutions are studied.  相似文献   

19.
By the semi-empirical interacting bonds method, the heats of oxygen and hydrogen adsorption in a dissociative form on the (100) face of Cu, Ag, Ni, Pd and Pt have been calculated. It has been shown that most stable are the multiply bonded adsorption forms. For the different bonding states, the heat of hydroxyl group formation from O2 and H2 varies but slightly. The calculated values are compared with the experimental data.
(100) Cu, Ag, Ni, Pd, Pt. , . - H2 O2. .
  相似文献   

20.
Conclusions Relatively highly purified preparations of lysyl-, phenylalanyl- and aspartyl-tRNA synthetases have been isolated from the 12-day mycelium of a strongly virulent form of the fungusV. dahliae and some of their physicochemical properties have been studied.Institute of Biochemistry, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 229–233, March–April, 1974.  相似文献   

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