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1.
Waihung Lo Lau Mei Ng Hong Chua Peter H. F. Yu Shirley N. Sin Po-Keung Wong 《Applied biochemistry and biotechnology》2003,107(1-3):581-591
Batch biosorption experiments were conducted to investigate the removal of Cu2+ ions from aqueous solutions by a series of bacterial strains isolated from a local activated sludge process. The characteristics
of 12 isolates were identified and examined for their ability to bind Cu2+ ions from aqueous solution. Among the isolates, two species exhibited biosorption capacity >40 mg of Cu/g of dry cell. Isotherms
for the biosorption of copper on bacterial cells were developed and compared, and the equilibrium data fitted well to the
Langmuir and Freundlich isotherm models. The biosorption of copper increased significantly with increasing pH from 2.0 to
6.0 regardless of the species. More than 90% of copper sorbed on the cells of Bacillus sp. could be recovered by washing with 0.1 M HNO3 for 5 min. The performance of two different desorption processes was also tested and compared. The results show that five
biosorption and desorption cycles are a better operation process than five successive biosorptions followed by one desorption
to remove and recover copper from aqueous solution. The biosorbent could be used for at least five biosorptions and desorption
cycles without loss of copper removal capacity. It can be concluded that the activated sludge or sludge-isolated bacteria
could be a potential biosorbent for copper removal. 相似文献
2.
Biosorption of copper (II) and cadmium (II) by live Phanerochaete chrysosporium immobilized by growing onto polyurethane foam material in individual packed bed columns over two successive cycles of sorption–desorption
were investigated in this study. Initial pH and concentrations of the metals in their respective solutions were set optimum
to each of those: 4.6 and 35 mg·l−1 in case of copper and 5.3 and 11 mg·l−1 for cadmium. The breakthrough curves obtained for the two metals during sorption in both the cycles exhibited a constant
pattern at various bed depths in the columns. The maximum yield of the columns in removing these metals were found to be,
respectively, 57% and 43% for copper and cadmium indicating that copper biosorption by the immobilized fungus in its column
was better than for cadmium. Recovery values of the sorbed copper and cadmium metals from the respective loaded columns by
using 0.1 N HCl as eluant was observed to be quite high at more than 65% and 75%, respectively, at the end of desorption in
both the cycles. Breakthrough models of bed-depth service time, Adams–Bohart, Wolborska, and Clark were fitted to the experimental
data on sorption of copper and cadmium in the columns, and only the Clark model could fit the sorption performance of the
columns well over the entire range of ratios of concentrations of effluent to influent, i.e., C/C
0 for both copper and cadmium biosorption. The kinetic coefficients of mass transfer and other suitable parameters in the system
were determined by applying the experimental data at C/C
0 ratios lower than 0.5 to the other three models. 相似文献
3.
An Cu(II)-imprinted interpenetrating polymer network (IPN) gel of epoxy-diethylenetriamine and methacrylic acid-acrylamide-N,N′-methylene-bis-(acrylamide) was synthesized by the ionic imprint polymer (IIP) technique. The first polymer network is formed by epoxy gelation
with diethylenetriamine. The other is formed by copper methacrylate co- polymerization with acrylamide and cross-linker N,N′-methylene-bis-(acrylamide). The adsorption–desorption characteristics of the IPN gel as a highly selective solid-phase extraction (SPE)
and preconcentration adsorbent for Cu2+ from aqueous solution were investigated. The experimental results show that trace Cu2+ ions can be quantitatively enriched at pH 5 with recovery >95%. The maximum static adsorption capacity of the ion-imprinted
functionalized gel adsorbent was 76 mg g−1. Comparing with non-imprinted IPN gel, the imprinted IPN gel has higher adsorption capacity and selectivity for Cu2+ by the static adsorption–desorption experiment. Simultaneously, the times of adsorption equilibration and complete desorption
were remarkably short. The precision (RSD) for 11 replicate adsorbent extractions of 20 ng mL−1 Cu2+ was 3.4%. The established procedure was applied to two real water samples with satisfactory results. The prepared ion-imprinted
IPN gel adsorbent was shown to be promising for solid-phase extraction coupled with atomic absorption spectrometry (AAS) for
the determination of trace copper in real samples. In addition, the coordination interaction of Cu2+ and functional groups of the IPN gel adsorbent was primarily discussed by FT-IR spectra. 相似文献
4.
Gennady I. Ostapenko 《Journal of Solid State Electrochemistry》2006,10(2):91-95
Investigations are carried out by potentiostatic method. It is found that at potentials ϕ less than 100 mV, a reaction rate
of copper deposition is limited by the formation and the three-dimensional growth of copper nuclei and the rate of copper
dissolution is limited by a two-dimensional growth of holes in the metal. The rate of nucleus growth was evaluated at 10−9...10−6 μm s−1 depending on the potential. At ϕ>120 mV, the reaction rate is limited by charge transport at the exchange current density
of 2.7 mA cm−2 and the anodic transfer coefficient αa≈ 0.45. The accumulation of a divalent copper phase on Cu/Cu4RbCl3I2 interface at anodic polarization is explained by a parallel course of Cu+ − e → Cu2+ reaction. 相似文献
5.
Ibrahim M. EI-Mehasseb Abd El-Motaleb M. Ramadan Raafat M. Issa 《Transition Metal Chemistry》2006,31(6):730-739
The oxidation of catechol by molecular oxygen in the presence of a catalytic amount of copper(II) complex with 2-methyl-3-amino-(3H)quinazoline-4-one (MAQ) and various anions (Cl−, Br−, ClO
4
−
, SCN−, NO
3
−
and SO
4
–
) was studied. The catecholase biomimetic catalytic activity of the copper(II) complexes has been determined spectrophotometrically
by monitoring the oxidative transformation of catechol to the corresponding light absorbing o-quinone (Q). The rate of the catalytic oxidation reaction was investigated and correlated with the catalyst structure, time,
concentration of catalyst and substrate and finally solvent effects. Addition of pyridine or Et3N showed a dramatic effect on the rate of oxidation reaction. Kinetic investigations demonstrate that the rate of oxidation
reaction has a first order dependence with respect to the catalyst and catechol concentration and obeying Michaelis–Menten
Kinetics. It was shown that the catalytic activity depends on the coordination environment of the catalyst created by the
nature of counter anions bound to copper(II) ion in the complex molecule and follows the order: Cl− > NO
3
−
> Br− > SO
4
–
> SCN− > ClO
4
−
. To further elucidate the catalytic activity of the complexes, their electrochemical properties were investigated and the
catecholase mimetic activity has been correlated with the redox potential of the Cu2+/Cu+ couple in the complexes. 相似文献
6.
Zhaoxiang Wu Francisco A. Fernandez-Lima Lisa M. Perez David H. Russell 《Journal of the American Society for Mass Spectrometry》2009,20(7):1263-1271
The dinuclear copper complex (α-cyano-4-hydroxycinnamic acid (CHCA) copper salt (CHCA)4Cu2), synthesized by reacting CHCA with copper oxide (CuO), yields increased abundances of [M + xCu − (x−1)H]+ (x = 1–6) ions when used as a matrix for matrix-assisted laser desorption ionization (355 nm Nd:YAG laser). The yield of
[M + xCu − (x−1)H]+ (x = 1∼6) ion is much greater than that obtained by mixing peptides with copper salts or directly depositing peptides onto
oxidized copper surfaces. The increased ion yields for [M + xCu − (x−1)H]+ facilitate studies of biologically important copper binding peptides. For example, using this matrix we have investigated
site-specific copper binding of several peptides using fragmentation chemistry of [M + Cu]+ and [M + 2Cu − H]+ ions. The fragmentation studies reveal interesting insight on Cu binding preferences for basic amino acids. Most notable
is the fact that the binding of a single Cu+ ion and two Cu+ ions are quite different, and these differences are explained in terms of intramolecular interactions of the peptide-Cu ionic
complex. 相似文献
7.
Peroxydisulfate (PDS) oxidizes N,N′-ethylenebis(isonitrosoacetyleacetoneimine)copper(II) complex, CuIIL, to the corresponding copper(III) complex, [CuIIIL]+. The kinetic runs were performed in the presence of EDTA to scavenge any trace metal impurities. The kinetics of the reaction
at constant pH, ionic strength, and temperature obeys the rate law d[CuIIIL]/dt = 2k
2[CuIIL][S2O8
2−] with k
2 having a value of (8.85 ± 0.32) × 10−2 M−1 s−1 at μ = 0.30 M and T = 25.0 °C. The rate constant k
2 is not affected by variation of pH over the range 3.60–5.20. The second order rate constant is also unaffected by changing
ionic strength. The values of k
obs were determined over the temperature 25.0–40.0 °C range. The enthalpy of activation, ∆H*, and entropy of activation, ∆S*, have been calculated as 34.9 ± 0.5 kJ mol−1 and −173.3 ± 11.4 J K−1 mol−1, respectively. The kinetics of this reaction, as far as we know, is the first evidence that copper(III) is the likely reactive
species in copper catalyzed PDS oxidation reactions. 相似文献
8.
Chan-Cheng Su Tsai-Tang Hwang Orchid Y. -P. Wang Sue-Lein Wang Fen-Ling Liao 《Transition Metal Chemistry》1992,17(2):91-96
The crystal and molecular structure of [Cu(HIm)4(BF4)2]-2hmpa (HIm=imidazole; hmpa=hexamethylphosphoramide) has been determined using three-dimensional x-ray diffraction data.
The CuII ion is coordinated centrosymmetrically by four imidazole ligands forming a basal plane, mean Cu−N 2.005 Å, and by two tetrafluoroborate
anions on the z axis, mean Cu−F 2.506 Å. The four imidazole ligands are inclined at 64.6±0.5° to the CuN4 coordination plane. The discrete CuII complexes and hexamethylphosphoramide molecules are interconnectedvia hydrogen bonding between the imidazole N−H group and hmpa oxygen atom. The hmpa has a tetrahedral configuration around P
with P=O 1.489 Å and mean P−N 1.629 Å. The deconvoluted d-d absorptions of the title compound yield an orbital sequence: dx
2−y2>dz
2>dxy>dyz=dxz. The properties of the Cu-imidazole bonds are discussed with reference to the electronic structures of the chromophores of
tetrakis(imidazole)copper(II) complexes having effective local symmetriesD
4h
andD
2h
. 相似文献
9.
Twelve aerobic bacteria from activated sludge were isolated and identified. These included both Gram-positive (e.g., Bacillus) and Gram-negative (e.g., Pseudomonas) bacteria. The biosorption capacity of these strains for three different heavy metals (copper, nickel, and lead) was determined
at pH 5.0 and initial metal concentration of 100 mg/L. Among these 12 isolates, Pseudomonas pseudoalcaligenes was selected for further investigation owing to its high metal biosorption capacity. The lead and copper biosorption of this
strain followed the Langmuir isotherm model quite well with maximum biosorption capacity (q
max) reaching 271.7mg of Pb2+/g of dry cell and 46.8 mg of Cu2+/g of dry cell at pH 5.0. Study of the effect of pH on lead and copper removal indicated that the metal biosorption increased
with increasing pH from 2.0 to 7.0. A mutual inhibitory effect was observed in the lead-copper system because the presence
of either ion affected the sorption capacity of the other. Unequal inhibitions were observed in all the nickel binary systems.
The increasing order of affinity of the three metals toward P. pseudoalcaligenes was Ni<Cu<Pb. The metal biosorptive potential of these isolates, especially P. pseudoalcaligenes, may have possible applications in the removal and recovery of metals from industrial effluents. 相似文献
10.
Biosorption of metal ions with Penicillium chrysogenum 总被引:1,自引:0,他引:1
Biosorption of metal ions with Penicillium chrysogenum mycelium is described in this article. Alkaline pretreatment was used to remove proteins and nucleic acids from cells, and
this treatment increased the adsorption capacities, for Cr3+ from 18.6 mg g−1 to 27.2 mg g−1, for Ni2+ from 13.2 mg g−1 to 19.2 mg g−1, for Zn2+ from 6.8 mg g−1 to 24.5 mg g−1. The adsorption of metal ions was strongly pH dependent. The mycelium could beused for large-scale removal of Cr3+ from tannery wastewater. The results show that this inexpensive mycelium adsorbent has potential in industry because of its
high adsorption capacity. The main chelating sites are amino groups (−NH2) of chitosan in the mycelium. A new model is established, which describes the relation of adsorption of metal ions on pH
according to amino group chelating with metal ions and H+. The relative errors of simulation for Cu2+, Ni2+, Zn2+, and Cr3+ are 4.66%, 5.45%, 11.55%, and 1.69%, respectively. 相似文献
11.
Dengeti Shrinivas Gunashekaran Savitha Kumar Raviranjan Gajanan Ramchandra Naik 《Applied biochemistry and biotechnology》2010,162(7):2049-2057
A highly thermostable alkaline xylanase was purified to homogeneity from culture supernatant of Bacillus sp. JB 99 using DEAE-Sepharose and Sephadex G-100 gel filtration with 25.7-fold increase in activity and 43.5% recovery.
The molecular weight of the purified xylanase was found to be 20 kDA by SDS-PAGE and zymogram analysis. The enzyme was optimally
active at 70 °C, pH 8.0 and stable over pH range of 6.0–10.0.The relative activity at 9.0 and 10.0 were 90% and 85% of that
of pH 8.0, respectively. The enzyme showed high thermal stability at 60 °C with 95% of its activity after 5 h. The K
m and V
max of enzyme for oat spelt xylan were 4.8 mg/ml and 218.6 μM min−1 mg−1, respectively. Analysis of N-terminal amino acid sequence revealed that the xylanase belongs to glycosyl hydrolase family
11 from thermoalkalophilic Bacillus sp. with basic pI. Substrate specificity showed a high activity on xylan-containing substrate and cellulase-free nature. The hydrolyzed product
pattern of oat spelt xylan on thin-layer chromatography suggested xylanase as an endoxylanase. Due to these properties, xylanase
from Bacillus sp. JB 99 was found to be highly compatible for paper and pulp industry. 相似文献
12.
The adsorption and activation of NO molecules on Cu-ZSM-5 catalysts with different Cu/Al and Si/Al ratios (from 0.05 to 1.4 and from 17 to 45, respectively) subjected to different pretreatment was studied by ultraviolet-visible diffuse reflectance (UV-Vis DR). It was found that the amount of chemisorbed NO and the catalyst activity in NO decomposition increased with an increase in the Cu/Al ratio to 0.35–0.40. The intensity of absorption bands at 18400 and 25600 cm−1 in the UV-Vis DR spectra increased symbatically. It was hypothesized that the adsorption of NO occurs at Cu+ ions localized in chain copper oxide structures with the formation of mono- and dinitrosyl Cu(I) complexes, and this process is accompanied by the Cu2+...Cu+ intervalence transfer band in the region of 18400 cm−1. The low-temperature activation of NO occurs through the conversion of the dinitrosyl Cu(I) complex into the π-radical anion (N2O2)− stabilized at the Cu2+ ion of the chain structure, [Cu2+-cis-(N2O2)−], by electron transfer from the Cu+ ion to the cis dimer (NO)2. This complex corresponds to the L → M charge transfer band in the region of 25600 cm−1. The subsequent destruction of the complex [Cu2+-cis-(N2O2)−] at temperatures of 150–300°C leads to the release of N2O and the formation of the complex [Cu2+O−], which further participates in the formation of the nitrite-nitrate complexes [Cu2+(NO2)−], [Cu2+(NO)(NO2)−], and [Cu2+(NO3)−] and NO decomposition products. 相似文献
13.
Dinuclear copper(II) complexes with acyldihydrazones of 2-hydroxy-5-nitroacetophenone (H4L) of the composition Cu2(Py)xL·mEtOH were synthesized and characterized. In these complexes, the coordination polyhedra of the copper atoms are linked to
each other by a polymethylene chain of different lengths, from one to five monomer units. The structure of the [Cu2L·4Mrf] complex (Mrf is morpholine) based on acyldihydrazone of malonic acid was established by X-ray diffraction. The copper(II) atoms in this complex are [4+1]-coordinated and are spaced by 6.94 Å. At room temperature, the signal in the ESR spectra
of solutions of the complexes based on acyldihydrazones of malonic, succinic, glutaric, and adipic acids has a seven-line
hyperfine structure with the constant of (35.3–38.8)·10−4 cm−1 (g = 2.109–2.112) due to exchange interactions between unpaired electrons and two equivalent copper nuclei. An increase in the
length of the polymethylene chain to five monomer units hinders exchange interactions, and the ESR signal of the complex based
on acyldihydrazone of pimelic acid has a four-line hyperfine structure with a
Cu = 72.7·10−4 cm−1 typical of mononuclear copper(II) complexes.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 229–234, February, 2007. 相似文献
14.
G. M. Larin A. N. Gusev Yu. V. Trush K. V. Rabotyagov V. F. Shul’gin G. G. Aleksandrov I. L. Eremenko 《Russian Chemical Bulletin》2007,56(10):1964-1971
Spacer-armed dinuclear copper(II) complexes with condensation products of isophthalic and terephthalic acid dihydrazides with salicylaldehyde and 2-hydroxyacetophenone
were synthesized and studied by EPR and X-ray diffraction. The compositions and structures of most of the complexes were determined
by elemental analysis, thermogravimetric analysis, and IR spectroscopy. The structure of the copper(II) complex with acyldihydrazone of salicylaldehyde and 1,3-benzenedicarboxylic acid (H4L) with the composition [Cu2L1·2morph·MeOH] (morph is morpholine) was established by X-ray diffraction. The CuII atoms are spaced by 10.29 Å and are structurally nonequivalent. One copper cation has a square-planar coordination formed
by donor atoms (2 N + O) of the doubly deprotonated acylhydrazine fragment and the N atom of the morpholine molecule. The
second copper atom is additionally coordinated by a methanol molecule through the oxygen atom, so that this copper atom is
in a tetragonal-pyramidal coordination with the oxygen atom in the axial position. The EPR spectra of liquid solutions of
the complexes based on 1,4-benzenedicarboxylic acid acyldihydrazones and 1,3-benzenedicarboxylic acid bis(salicylidene)hydrazone
at room temperature show a four-line hyperfine structure with the constant a
Cu = 54.4–67.0·10−4 cm−1 (g = 2.105–2.147), which is indicative of the independent behavior of the paramagnetic centers. The EPR spectrum of a solution
of the complex based on isophthalic acid and 2-hydroxyacetophenone shows the seven-line hyperfine structure corresponding
to two equivalent copper nuclei (g = 2.11, a
Cu = 36.5·10−4 cm−1).
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1898–1905, October, 2007. 相似文献
15.
Junpei Zhou Huoqing Huang Kun Meng Pengjun Shi Yaru Wang Huiying Luo Peilong Yang Yingguo Bai Bin Yao 《Applied biochemistry and biotechnology》2010,160(5):1277-1292
A bacterial strain, Streptomyces sp. TN119, was isolated from the gut of Batocera horsfieldi larvae and showed xylanolytic activity. A degenerate primer set was designed based on the base usage of G and C in Actinobacteria xylanase-coding sequences belonging to the glycosyl hydrolases family 10 (GH 10), and used to clone the partial xylanase
gene from Streptomyces sp. TN119. A modified thermal asymmetric interlaced (TAIL)-PCR specific for high-GC genes, named GC TAIL-PCR, was developed
to obtain the full-length xylanase gene (xynA119; 1089 bp). Rich in GC content (67.8%), xynA119 encodes a new GH 10 xylanase (XynA119), which shares highest identity (48.8%) with an endo-1,4-β-xylanase from Cellulosimicrobium sp. HY-12. Recombinant XynA119 was expressed in Escherichia coli BL21 (DE3) and purified to electrophoretic homogeneity. The enzyme showed maximal activity at pH 6.5 and 60 °C, was stable
at pH 4.0 to 10.0 and 50 °C, was resistant to most chemicals (except for Cu2+, Mn2+, Ag+, Hg2+ and SDS) and trypsin, and produced simple products. The specific activity, K
m, V
max, and k
cat using oat-spelt xylan as substrate were 57.9 U mg−1, 1.0 mg ml−1, 74.8 μmol min−1 mg−1, and 49.2 s–1, respectively. 相似文献
16.
Biosorption of three divalent metals, viz., lead, copper, and cadmium in ternary aqueous mixtures was studied using Phanerochaete chrysosporium in batch shake flasks. The mixtures were prepared containing the metals at their either varying optimum or equal initial
concentration combinations in aqueous solution of pH optimum to each of the metals. Following were the optimum initial concentration
ranges of the metals in mixture: lead, 60–100 mg/L; copper, 20–60 mg/L; and cadmium, 5–15 mg/L. And, for varying these optimum
concentration levels of the metals, a 23 full factorial design of experiments was employed. The results revealed that an increase in lead and cadmium concentrations
helped in their better biosorption by the fungus, but an increase in initial copper concentration slightly diminished its
removal. Statistical analysis of the results in the form of analysis of variance and Student t test gave a clear interpretation on the roles of both the individual metals and their interactions in the uptake of metals
from mixture. Compared to the uptake of metals when presented individually, lead biosorption in mixture was found to be enhanced
to a degree as high as 99%; on the other hand, copper and cadmium removals from mixtures were inhibited to the extent of 100%
and 98%, respectively. However, this extent of inhibition or enhancement in the metal removals compared to the individual
removals was less in mixtures containing all equal concentrations of the metals. 相似文献
17.
J. Marešová L. Remenárová M. Horník M. Pipíška J. Augustín J. Lesný 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1329-1337
The aim of this paper was to obtain quantitative data of foliar uptake kinetics and long distance transport of zinc in tobacco
(Nicotiana tabacum L.) and hop (Humulus lupulus L.) plants. Zinc was used as a model of microelement and toxic metal, tobacco and hop as a representatives of agriculturally
important plants. A tip of leaf blade was immersed in the solution spiked with 65ZnCl2 and foliar uptake and translocation to other parts of the plant grown in nutrient solution was measured by gamma-spectrometry
and autoradiography. We found that foliar zinc uptake by both plants is dependent on the initial metal concentration within
the range C
0 = 10–100 μmol dm−3 ZnCl2. Zinc is immobilized mainly in immersed part of the contact leaf and only <1% is transported to non-immersed parts of the
leaf. At C
0 = 0.1 mmol dm−3 ZnCl2 concentrations >2.5 mg/g Zn and 4.8 mg/g Zn (dry wt.) in immersed part of tobacco and hop leaf plant, respectively were found
after 5 days of exposure. Low mobility of zinc entering the plant via the leaf surface can be attributed to the immobilization
of zinc into Zn–ligand complexes with high stability constants log K at pH 6.0–8.0, such as the reaction products of Zn2+ ions with citric acid, histidine or phosphates. Zinc can be extracted from dried leaves by the solutions of inorganic salts,
carboxylic acids, amino acids and synthetic complexing ligands such as EDTA. Anionic (SDS) and non-ionic (Tween 40) surfactants
causes the decrease of the Zn foliar uptake, but not translocation of Zn from the contact leaf area. Obtained data are discussed
from the point of view of possible limited efficiency of liquid formulations designed for practical applications as Zn foliar
fertilizers. 相似文献
18.
A new type of two-dimensional network was found in the hydrogen-bonded molecular assemblies of copper(II) α,β-unsaturated
carboxylate complexes with TMP [OP(OMe)3], {Cu2A4(H2O)2[OP(OMe)3]}
n
[(1) A = CH2=CHCO2
−; (2) A = CH2=C(Me)CO2
−]. The crystal structure of (1) has been determined by single-crystal X-ray diffraction. Both complexes are unique in terms of a sheet structure brought
about by O—H ⋯ O hydrogen-bonded interactions both between neighbouring Cu2A4(H2O)2 units and between Cu2A4(H2O)2 and OP(OMe)3 molecules. The electronic reflectance spectra in the solid state suggest a square pyramidal coordination environment around
the copper(II) atom. Room temperature X-band e.s.r. spectra of powered samples and variable-temperature magnetic susceptibility
studies indicate the presence of strong antiferromagnetic exchange interactions between two copper(II) atoms, with 2J = −310 cm−1 for (1) and 2J = −304 cm−1 for (2) respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
Spherical copper selenide nanoparticles (NPs) were prepared by a simple reaction of sodium selenosulfate with metal copper
at room temperature in alkaline Na2SeSO3 aqueous solution. It is a galvanic process that operates on a coupled anodic copper oxidation and selenosulfate reduction.
1-Thioglycerol is found to catalyze this reaction. With gold and graphite as the positive electrodes, nanocrystallites of
nonstoichiometric copper selenide (Cu2 − x
Se) and stoichiometric copper selenides (CuSe) were produced, respectively. The XRD study shows that the produced CuSe and
Cu2 − x
Se are in the pure hexagonal phase and clausthalite phase, respectively. Transmission electron microscopy images show that
the diameters of the produced CuSe and Cu2 − x
Se NPs are in the range of 10∼20 and 5∼15 nm, respectively. 相似文献
20.
V. F. Shul’gin E. A. Sarnit O. V. Konnik E. B. Rusanov A. S. Bogomyakov V. I. Ovcharenko V. V. Minin 《Russian Journal of Coordination Chemistry》2012,38(1):44-49
The structures and results of the static magnetic susceptibility investigation of the copper(II) binuclear complex with salicylic
acid diacyl hydrazide (H2L), [Cu2(L)(Py)4] (I), and the copper(II) trinuclear complex with diacyl dihydrazide of salicylic and glutaric acids (H6L′), [Cu3(L′)(Py)4] · 2Py (II), are described. The exchange antiferromagnetic interactions between the paramagnetic centers with the exchange interaction
parameter −2J = 119 cm−1 for dimer I and 14 cm−1 for trinuclear complex II are detected. 相似文献