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61.
Adsorption of Metanil Yellow Azoic Dye from Aqueous Solution onto Mg‐Fe‐NO3 Layered Double Hydroxide
Dr. Kamellia Nejati Zolfaghar Rezvani Mahsa Mansurfar Abolfazl Mirzaee Mehrdad Mahkam 《无机化学与普通化学杂志》2011,637(11):1573-1579
We report the preparation and characterization of a layered double hydroxide (LDH) adsorbent for azoic dye, metanil yellow (yellow GX; YGX) removal. The nanoparticles of Mg‐Fe‐LDH‐NO3 adsorbent were prepared with Mg/Fe molar ratio of 3:1 by a hydrothermal process and coprecipitation method at pH 9.5 and were characterized by X‐ray powder diffraction (XRPD), thermal gravimetric analysis (TGA), elemental analysis, and Fourier transform infrared spectroscopy (FT‐IR). The size and morphology of nanoparticles were examined by scanning electron microscopy (SEM). The XRD patterns indicate that the intercalation of YGX between the LDH layers has not occurred and surface adsorption has happened. In the adsorption experiments, the Gibbs free energy ΔG0 values, the enthalpy ΔH0, and entropy ΔS0 was determined. The isotherms showed that the adsorption of YGX by Mg‐Fe‐LDH‐NO3 was both consistent with Langmuir and Freundlich equations. 相似文献
62.
Sanati MH Torkaman G Hedayati M Dizaji MM 《Journal of photochemistry and photobiology. B, Biology》2011,103(2):180-185
Injury potential may have a triggering biological role in wound healing. In this study, the effect of photostimulation to promote wound healing and its effect on injury potential was investigated using the Ga-As and He-Ne lasers. In this study, 30 healthy male Sprague-Dawley rats were randomly divided into a control and two laser groups, He-Ne and Ga-As laser. A 2.5 cm craniocaudal full-thickness skin incision was made on each animal's dorsal region. Differential skin surface potential was measured before and immediately after the injury and also up to the 21st day, every other day. Wound surface area was also measured. Immediately after injury, wound potential significantly increased in all three groups. Maximum positive peak of injury potential was greater in Ga-As group compared to He-Ne laser and control groups (P<0.05) and lasting period of maximum positive potential in two laser groups was longer than that in the control group. There were no significant differences between the mean potential of before wounding and after the 15th, 17th, and 19th day in Ga-As, He-Ne, and control group, respectively (P>0.05). On the other hand, Ga-As and He-Ne laser facilitated the normal distribution of skin potential after wounding. These findings demonstrate that Ga-As laser may be more effective on wound closure and on returning the injury potential to normal level than the He-Ne laser. 相似文献
63.
Morra S Valetti F Sadeghi SJ King PW Meyer T Gilardi G 《Chemical communications (Cambridge, England)》2011,47(38):10566-10568
[FeFe]-hydrogenases are efficient natural catalysts that can be exploited for hydrogen production. Immobilization of the recombinant [FeFe]-hydrogenase CaHydA was achieved for the first time on an anatase TiO(2) electrode. The enzyme is able to interact and exchange electrons with the electrode and to catalyze hydrogen production with an efficiency of 70%. 相似文献
64.
Semigroup Forum - Let S be a foundation topological semigroup and $$M_a(S)$$ the space of all measures $$\mu \in M(S)$$ for which the maps $$x\longmapsto |\mu |*\delta _{x}$$ and $$x\longmapsto... 相似文献
65.
In this study, alumina nanoparticles and film were synthesized by sol–gel method and thermally grown. The chemical composition, morphology, and structural properties of the grain nanostructures of the nanoaggregate aluminum atoms on the silicon surface are characterized by X-ray diffraction, energy dispersive spectroscopy, and scanning electron microscopy techniques which show that the atomic ratio of Al and O elements is about 60:45 and the mass ratio is about 70:31. This point reveals that there is no intermediate layer between Al2O3 and the silicon substrate. In conclusion, this nanoparticle shows good electron conductivity at the surface of a carbon paste electrode that shows its ability in the preparation of a nanosensor in morphine analysis. The linear response range and detection limit were found to be 0.1–550 and 0.03 μmol L?1, respectively. The proposed sensor was successfully applied for the determination of morphine in real samples such as human urine and drug. 相似文献
66.
Hamid R. Memarian Majid M. Sadeghi Ahmad R. Momeni Dietrich D?pp 《Monatshefte für Chemie / Chemical Monthly》2002,9(4):661-667
Some novel 3,5-diacetyl-1,4-dihydropyridine derivatives were synthesized; their photochemical behaviour was studied under oxygen or argon atmosphere. Irradiation of these compounds resulted in the aromatization of the ring and formation of 3,5-diacetylpyridine derivatives. The presence of oxygen plays an important role in the type, rate, or failure of oxidation. Irradiation of these compounds with of 2-furyl or 5-methyl-2-furyl substituents in position 4 under argon resulted in the formation of a pyridine ring with retention of these substituents, whereas loss of these substituents and ring aromatization was observed upon irradiation under oxygen. 相似文献
67.
The electrolyte NRTL model [C.C. Chen, L.B. Evans, AIChE J. 32 (1986) 444–454] and electrolyte Wilson model [E. Zhao, M. Yu, R.E. Sauvé, M. Khoshkbarchi, Fluid Phase Equilibr. 173 (2000) 161–175] have been extended for the representation of the dynamic viscosity of strong electrolyte solutions. The models are based on Eyring's absolute rate theory and the electrolyte NRTL and Wilson models for calculating the excess Gibbs energy of activation of the viscous flow. The utility of the models is demonstrated with a successful representation of the viscosity of several electrolyte solutions at different temperatures. The results show that, the model is valid for the whole range of salt concentration and it is reliable for correlation of the viscosity of electrolyte solutions at different temperatures by only four adjustable parameters per binary system. 相似文献
68.
Using the light absorption technique in a 132Xe afterglow plasma, we have measured the relative transition probabilities for several xenon lines which have the metastable 6s[]2 or the resonant 6s[]1 states as their lowest transition level. Because the transition probabilities of the 8819 Å (6p[]3 ? 6s[]2) and 8280 Å (6p[]0 ? 6s[]1) lines are relatively well known, we have chosen these as reference lines and have thus been able to determine the absolute values of the transition probabilities for 19 xenon lines corresponding to transitions from 6p, 6p′, 7p, 8p, 9p, 4f and 5f to 6s[]2, and for four lines corresponding to the transitions 6p?6s[]1. 相似文献
69.
Peyman Afshani Mahsa Ghandehari Mahya Ghandehari Hamed Hatami Ruzbeh Tusserkani Xuding Zhu 《Journal of Graph Theory》2005,49(4):325-335
This paper proves that if G is a graph (parallel edges allowed) of maximum degree 3, then χ′c(G) ≤ 11/3 provided that G does not contain H1 or H2 as a subgraph, where H1 and H2 are obtained by subdividing one edge of K (the graph with three parallel edges between two vertices) and K4, respectively. As χ′c(H1) = χ′c(H2) = 4, our result implies that there is no graph G with 11/3 < χ′c(G) < 4. It also implies that if G is a 2‐edge connected cubic graph, then χ′c(G) ≤ 11/3. © 2005 Wiley Periodicals, Inc. J Graph Theory 49: 325–335, 2005 相似文献
70.
The excitation-transfer reaction in thermal energy collisions of state-selected metastable Ar*(3P2) and Ar*(3P0) atoms with ground state H atoms, giving excited H*(n = 2) atoms, has been studied with the stationary afterglow technique. The rate constant for the excitation of H atoms by Ar*(3P2) has been found to be more than one order of magnitude larger than in excitation by Ar*(3P0). This difference in the reactivity of two metastable species is explained to be a consequence of the attractive nature of the D(2II) and E(2Σ+) potentials that develop from the Ar*(3P2)+H entrance channel and which give curve crossing with the B(2II) and C(2Σ+ potentials, respectively, leading to the Ar+H*(n=2) exit channel, whereas only a repulsive 4II (Ω=) potential develops from the Ar*(3P0+H entrance channel. 相似文献