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61.
IR spectra of Mn(en)M(CN)4·2C6H6 (M=Cd or Hg), and IR and Raman spectra of Cd(en)M(CN)4·2C6H6 (M=Cd or Hg) clathrates are reported. The spectral features suggest that the first two compounds are similar in structure to the later two Td-type clathrates. 相似文献
62.
Four new trinuclear Fe(III) complexes involving tetradenta Schiff bases N,N
1
-bis(salicylidene) ethylenediamine-(salenH2) or bis(salicylidene)-o-phenylenediamine-(salophH2) with 2,4,6-tris(2,5-dicarboxyphenylimino-4-formylphenoxy)-1,3,5-triazine (DCPI-TRIPOD) or 2,4,6-tris(4-carboxyphenylimino-4′-formylphenoxy)-1,3,5-triazine (CPI-TRIPOD) have been synthesized and characterized by means of elemental
analysis carrying out 1H-n.m.r., i.r. spectroscopy, thermal analyses and magnetic susceptibility measurements. The complexes can also be characterized
as high-spin distorted octahedral FeIII bridged by carboxylic acids. The tricarboxylic acids play a role as bridges for weak antiferromagnetic intramolecular exchange. 相似文献
63.
New adducts of ethylenediamine (en), N,N-dimethylethylenediamine (ndmen) and N,N′-dimethylethylenediamine (dmen) with squarate as counter-ions were synthesized and characterized by physico-chemical methods
(IR and UV/vis spectroscopy, magnetic susceptibility and thermoanalytical measurements). The crystal structure of tris(ethylenediamine)cobalt(III)
1.5 squarate hexahydrate, [Co(en)3](sq)1.5 · 6H2O, was determined by single crystal X-ray diffraction. Co(III), Ni(II) and Cu(II) ions in the monomeric octahedral tris(ethylenediamine)cobalt(III)
1.5 squarate hexahydrate (1), tris(ethylenediamine)nickel(II) squarate 0.5 hydrate (2) and diaquabis(ethylenediamine)copper(II) squarate dihydrate (3) are chelated by ethylenediamines through two amine nitrogen atoms. Cu(II) atoms in the diaquabis(ndmen)copper(II) squarate
(4) and diaquabis(dmen)copper(II) squarate (5) monomeric octahedral complexes are coordinated by ndmen and dmen molecules through two amine nitrogen atoms in a bidentate
chelating manner. Water molecules complete the octahedral coordination. The orange (1), violet (4) and violet (5) complexes upon heating transform to claret, green and green species on dehydration, respectively, which revert immediately
after cooling in the open atmosphere. The violet (3) complex upon heating loses water molecules yielding a deep blue dehydrated species, which on further heating undergoes an
exothermic phase transition accompanied by thermochromism, deep blue to brown in the solid state. The decomposition mechanism
and thermal stability of the solid complexes are interpreted in terms of their structures. The final decomposition products
– the respective metal oxides – were identified by IR spectroscopy. 相似文献
64.
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
65.
Güneş S. Kürkçüğlu Ziya Kantarci Resmigül Coşkun Mustafa Şenyel 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(1-2):129-137
The host complex Cd(Cyclohexylamine)2Pd(CN)4 has been prepared in powder form. The spectral data suggest that the structure of this complex issimilar to those of the Hofmann-dma-type hosts. The sorption processes of thearomatic guests (benzene, toluene,o-, m-, p-xylene, naphthalene, 1,2-, 1,3-, 1,4-dichlorobenzene and 1,4-dibromobenzene) in this host have been examined at room temperature by gravimetric and spectroscopic measurements.The desorption of the benzene guest against time has been measured. The hoststructure changes on inclusion of the guests and recovers after liberations. Thehost complex has been suggested as sorbents for selective absorption. 相似文献
66.
Orhan Acar A. Rehber Türker Ziya Kl? 《Fresenius' Journal of Analytical Chemistry》1997,357(6):656-660
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
67.
Babanly Dunya Mahammad Aliev Ziya Saxaveddin Majidzade Vusala Asim Tagiyev Dilgam Babir Babanly Mahammad Baba 《Journal of Thermal Analysis and Calorimetry》2018,134(3):1765-1773
Journal of Thermal Analysis and Calorimetry - The phase equilibria in the ternary Tl–Se–I system have been investigated by means of differential thermal analysis, X-ray powder... 相似文献
68.
69.
A new homonuclear and heterodinuclear pyridine-2,6-dicarboxylate complexes, formulated as (enH2)[Cu(dipic)2]·2.5H2O (1) and [Cu(μ-dipic)2Zn(H2O)5]·2H2O (2) (en = ethylenediamine, dipic = pyridine-2,6-dicarboxylate) were synthesized according the reactions between the three species of copper(II) and zinc(II) nitrate, ethylenediamine and pyridine-2,6-dicarboxylic acid. Complexes have been characterized by the methods of elemental, spectroscopic (IR and UV–Vis), thermal (TG/DTG, DTA) analysis, magnetic measurement and single crystal X-ray diffraction. Correlation coefficient, activation energies, E∗; pre-exponential factor, A; entropies, S∗; enthalpies, H∗ and Gibbs free energies, G∗ of the thermal decomposition reactions have been calculated under the derivations from thermogravimetric (TG) and differential thermogravimetric (DTG) curves, using the Coats–Redfern and Horowitz–Metzger methods. Complex 1 belonged to a six-coordinate behavior with a distorted octahedral geometry around Cu(II), that the structure contains two pyridine-2,6-dicarboxylate species as a tridentate ligands and ethylenediaminium cation as a counter ion as well as 2.5 uncoordinated water molecules. On the other hand complex 2 contains six-coordinated Cu(II) and Zn(II) ions, which are linked by two O atoms of the same carboxyl group from dipicolinic acid. The dipicolinate dianions again behave as tridentate ligands in 2. Two uncoordinated water molecules are also present in the structure. The structure units of 1 and 2 are mutually held by the hydrogen bonds and π?π interactions. There is also a C–O?π interaction in 2. The Cu(II) complexes are connected to one another via O–H?O hydrogen bonds, forming water clusters, which play an important role in the stabilization of the crystal structure. In the water clusters, the water molecules are trapped by the cooperative association of coordination interactions as well as hydrogen bonds. 相似文献
70.
Raoul R. Nigmatulin Alexander P. Alekhin Dumitru Baleanu Erdal Dinç Zafer Üstündağ Haslet Ekşi Ali Osman Solak 《Electroanalysis》2010,22(4):419-426
The effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms was studied for the statistical characterization of nitrobenzene (NB) and nitroazobenzene (NAB)‐modified glassy carbon (GC) surfaces. Both NB and NAB nanofilms were obtained by the electrochemical reduction of the diazonium tetrafluoroborate salts in acetonitrile using cyclic voltammetry (CV). The modified surfaces were denoted as GC‐(NB)n and GC‐(NAB)n, respectively, where n indicates the number of CV cycles performed during modification. Reflective IR signals of the normalized NB and NAB nanofilms and GC were used for the quantitative evaluation of the effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms. The detection and quantitative ‘reading’ of the influence of number of CV cycles were realized in the frame of a new error controllable approach that was applied for analysis of all available set of data. This approach includes in itself the following basic steps: (a) the procedure of the division (normalization) on the GC spectra, (b) the comparison of the smoothed spectra for their statistical proximity in the frame of the statistics of the fractional moments, (c) extraction of possible calibration parameters for possible calibration of the normalized spectra with respect to the number of CV cycles. These three basic steps are becoming effective for detection of the influence of some external factors. In our case it is important to detect the influence of the factor n characterizing CV cycles. 相似文献