共查询到20条相似文献,搜索用时 15 毫秒
1.
L. N. Mazalov Yu. P. Dikov N. A. Kryuchkova V. V. Sokolov I. Yu. Filatova E. A. Korotaev A. D. Fedorenko 《Journal of Structural Chemistry》2010,51(1):59
The charged state of atoms in layered cation-substituted disulfides CuCr1?x V x S2 (x = 0?0.4) was studied using X-ray photoelectron spectroscopy. The study was performed with polycrystalline powder and ceramic samples of chromium-copper disulfides. CuCr1?x V x S2 samples were shown to comprise differently charged atoms of chromium, copper and vanadium, the charged state of which varies with the concentration of vanadium cations (x). 相似文献
2.
Ali Ayati Majid M. Heravi Mansoureh Daraie Bahareh Tanhaei Fatemeh F. Bamoharram Mika Sillanpaa 《Journal of the Iranian Chemical Society》2016,13(12):2301-2308
A novel nanomagnetic composite heteropolyacid immobilized chitosan/Fe3O4 was prepared via a facile one-pot synthetic approach. This magnetically recoverable nanocatalyst, H3PMo12O40/chitosan/Fe3O4 (PMo/chit/Fe3O4), was fully characterized by XRD, FTIR, SEM and EDX analysis methods. A rapid, efficient and the chemoselective synthesis of different pyrano-pyrazole derivatives was achieved in excellent yields via a one-pot four-component reaction in the presence of catalytic amount of PMo/Chit/Fe3O4. 相似文献
3.
Summary. A simple, general, and high yielding method has been developed for the synthesis of S-aryl/alkyl-O-aryl/alkyl thiolcarbonates from various chloroformates and disulfides by reductive cleavage of the S–S bond with a Zn/AlCl3 system in dry acetonitrile at 80°C. 相似文献
4.
M. N. Smirnova M. A. Kop’eva E. N. Beresnev L. V. Goeva N. P. Simonenko G. E. Nikiforova V. A. Ketsko 《Russian Journal of Inorganic Chemistry》2018,63(4):439-443
A powderlike material of composition MgFe1.6Ga0.4O4 was synthesized by gel combustion using a glycine–hexamethylenetetramine mixture. The gel produced by the synthesis was studied by thermal analysis (TGA/DSC) and IR spectroscopy. This mixture was shown to be efficient for obtaining homogeneous nanosized MgFe1.6Ga0.4O4. The morphology of the powders was characterized by scanning electron microscopy and X-ray powder diffraction analysis. 相似文献
5.
M. N. Smirnova M. A. Kop’eva E. N. Beresnev L. V. Goeva N. P. Simonenko G. E. Nikiforova A. V. Trukhanov V. A. Ketsko 《Russian Journal of Inorganic Chemistry》2018,63(10):1257-1261
A powdery material Mg(Fe0.8Ga0.2)2O4 has been prepared by combusting a gel containing magnesium(II), iron(III), and gallium(III) nitrates and a glycine–starch mixture. The gel produced during the synthesis has been studied by thermal analysis (TGA/DSC) and IR spectroscopy. This mixture has been shown to be efficient to produce a homogeneous nanosized powderlike material Mg(Fe0.8Ga0.2)2O4. The morphology and properties of ceramic samples are characterized by scanning electron microscopy, X-ray powder diffraction, neutron diffraction, and vibrational magnetometry. 相似文献
6.
Devdutt Chaturvedi Nisha Mishra Amit K. Chaturvedi Virendra Mishra 《Monatshefte für Chemie / Chemical Monthly》2008,139(12):1467-1470
A single-step novel protocol for the preparation of symmetrical trithiocarbonates from a corresponding variety of primary,
secondary, and tertiary alcoholic tosylates using the Cs2CO3/CS2 system, was developed. This protocol is mild and more efficient than the reported methods.
Correspondence: Devdutt Chaturvedi, Bio-Organic Chemistry Division, Indian Institute of Integrative Medicine, Canal Road,
Jammu-Tawi-18000, J&K, India. 相似文献
7.
Phonthep Nuankaeo Anukorn Phuruangrat Budsabong Kuntalue Phattranit Dumrongrojthanath Titipun Thongtem Somchai Thongtem 《Russian Journal of Applied Chemistry》2016,89(5):830-835
Highly efficient visible-light-driven Ag3PO4/Bi2MoO6 hybrid photocatalysts with different mole ratios of Ag3PO4 were prepared via sonochemical method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that product are cubic Ag3PO4 nanoparticles supported on orthorhombic Bi2MoO6 nanoplates. Under visible light irradiation (>420 nm), the Ag3PO4/Bi2MoO6 photocatalysts displayed the higher photocatalytic activity than pure Bi2MoO6 for the decolorization of rhodamine B (RhB). Among the hybrid photocatalysts, 10% Ag3PO4/Bi2MoO6 exhibited the highest photocatalytic activity for the decolorization of RhB due to the efficient separation of electron–hole pairs. 相似文献
8.
Tahereh Soleymani Ahooie Najmedin Azizi Issa Yavari Mohammad Mahmoudi Hashemi 《Journal of the Iranian Chemical Society》2018,15(4):855-862
A green, reliable synthetic method and highly efficient one-pot three-component synthesis of 2,4,5-trisubstituted imidazoles from 1,2-diketones, aldehydes and ammonium acetate in the presence of recyclable magnetic graphitic carbon nitride nanocomposite (Fe3O4@g-C3N4) has been developed. Various imidazole derivatives were obtained in moderate to excellent yields and high purity after recrystallization from ethanol. Interestingly, the low-cost Fe3O4@g-C3N4 a nontoxic and inexpensive catalyst showed excellent recyclability using an external magnet without loss of parent catalytic activity even after ten cycles and its provides new opportunities for the truly environmental friendliness methodology. 相似文献
9.
A very simple procedure for the efficient oxidation of thiols to disulfides catalyzed by I2/CeCl3·7H2O in graphite and ethyl acetate as the solvent, in an open system at room temperature is described. The reaction proceeds cleanly under mild conditions and was performed with aromatic, aliphatic, and heterocyclic thiols. 相似文献
10.
Zakaria Benzekri Sara Sibous Houda Serrar Ali Ouasri Said Boukhris Ali Rhandour Abdelaziz Souizi 《Journal of the Iranian Chemical Society》2018,15(12):2781-2787
In this work, the condensation of aromatic aldehydes with different two-substituted aniline catalyzed by NH3(CH2)5NH3BiCl5 as heterogeneous and recyclable catalyst was reported. It was demonstrated that NH3(CH2)5NH3BiCl5 can act as an efficient and active catalyst and is reusable for six runs without a significant loss of their catalytic activity. Simple preparation of the catalyst, high catalytic activity and good reusability are noteworthy advantages of this catalytic system in the synthesis of benzoxazole, benzimidazole and benzothiazole heterocycles at room temperature under solvent-free conditions. 相似文献
11.
Qingwen Tian Guigan Fang Yingqiao Shi Laibao Ding Aixiang Pan Long Liang Naixu Li Jiancheng Zhou 《Research on Chemical Intermediates》2017,43(3):1395-1407
A novel SrTiO3/BiPO4 heterostructure with different amounts of SrTiO3 have been successfully prepared through the hydrothermal process. The photocatalysts were characterized by X-ray powder diffraction, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic performance was evaluated by degrading the methylene blue dye solution under UV light. Results showed that the samples displayed excellent photocatalytic degradation efficiency due to the highly efficient suppression of the recombination of electron–hole pairs. A possible mechanism of SrTiO3/BiPO4 heterojunctions was discussed. The research indicated that the as-prepared SrTiO3/BiPO4 heterogeneous photocatalyst can be used as an effective material for degrading industrial organic wastewater. 相似文献
12.
Narottam Gharah Krishna Chowdhury Monika Mukherjee Ramgopal Bhattacharyya 《Transition Metal Chemistry》2008,33(5):635-642
A green heteropolyblue compound, (PPh4)4[PMo12O40] · 3DMF(1), has been synthesized from MoO3, H2O2 and H3PO4 in acetylacetone medium and crystallized from N,N-dimethylformamide. Compound 1 was characterized by analytical and spectroscopic methods, and X-ray structure analysis. The compound is a one-electron paramagnet
and shows a featureless and cubic EPR spectrum with <g> = 1.95 in DMF glass. The complex shows a Mo(V)–Mo(IV) couple, which
has been studied by cyclic voltammetric and coulometric methods. The compound acts as an efficient olefin epoxidation catalyst
with H2O2 as oxidant and NaHCO3 as co-catalyst.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
13.
Uraiwan Sirimahachai Nicholas Ndiege Ramesh Chandrasekharan Sumpun Wongnawa Mark A. Shannon 《Journal of Sol-Gel Science and Technology》2010,56(1):53-60
Nanosized TiO2 and nano-anatase TiO2 decorated on SiO2 spherical core shells were synthesized by using a sol–gel method. The synthesized pure TiO2 nano particle and TiO2 grafted on SiO2 sphere with various ratios have been characterized for their structure and morphologies by X-ray diffraction (XRD), X-ray
photoelectron spectroscopy (XPS), Fourier transform infrared spectrophotometry (FTIR) and transmission electron microscopy
(TEM). Their surface areas were measured using the BET method. The photocatalytic activity of all nanocomposites was investigated
using methylene blue as a model pollutant. The synthesized TiO2/SiO2 particles appeared to be more efficient in the degradation of methylene blue pollutant, as compared to pure TiO2 particles. 相似文献
14.
A nontoxic and inexpensive TiO2/MoS2 nanocomposite was prepared and employed as an efficient photocatalyst for the synthesis of symmetrical disulfides under visible light irradiation at room temperature. Both aryl and alkyl thiols survived the reaction conditions, affording the corresponding disulfides in good to excellent yields. The photocatalyst could be easily recovered by simple centrifugation and filtration and reused several times without significant loss in its activity. 相似文献
15.
V. F. Gareev R. M. Sultanova R. Z. Biglova V. A. Dokichev Yu. V. Tomilov 《Russian Chemical Bulletin》2008,57(8):1784-1786
A new efficient catalytic system consisting of Cu(OAc)2, 2,4-lutidine, and ZnCl2 was found for the cyclopropanation of unsaturated compounds with methyl diazoacetate. In the case of conjugated dienes, the
process occurs regioselectively at the most alkylated C=C bond.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1750–1752, August, 2008. 相似文献
16.
Ashok Kumar Chakraborty Md. Rashidul Islam Md. Helal Uddin Md. Masudur Rhaman 《Journal of Cluster Science》2018,29(1):67-74
A highly efficient and visible light (λ ≥ 420 nm) responsive composite photocatalyst, Co3O4/FeWO4 was prepared by simple impregnation method. The heterojunction semiconductors Co3O4/FeWO4 demonstrated notably high photocatalytic activity over a wide range of composition than the individual component Co3O4 or FeWO4 for the complete degradation of 1,4-dichlorobenzene (DCB) in aqueous phase under visible light irradiation. The photocatalytic activity of composite was optimized at 1/99 Co3O4/FeWO4 composition. After 2 h of visible light irradiation 51% decomposition of 1,4-dichlorobenzene (DCB) was observed utilizing 1/99 Co3O4/FeWO4 photocatalyst while the end members demonstrated a negligible degradation under the same experimental condition. The valence band (VB) and conduction band (CB) of Co3O4 is located above the VB and CB of FeWO4, respectively. Both the semiconductors Co3O4 and FeWO4 exhibit strong absorption over the wide range of visible light. The obviously enhanced photocatalytic performance of Co3O4/FeWO4 composite has been discussed on the hole (h+) as well as electron (e?) transfer mechanism between the VB and CB of individual semiconductors. 相似文献
17.
Bingtong Wang Zongbin Zhang Xinyu Zhang Shixin Sun Lin Wu Rong Xing 《Chemical Papers》2018,72(3):643-649
A simple, efficient, and eco-friendly catalytic system for the oxidation of cyclohexene to adipic acid with H2O2 catalyzed by H2WO4 in Brønsted acidic ionic liquids under solvent-free conditions has been developed. Reaction conditions such as the catalysts, the types of anions and cations for Brønsted acidic ionic liquids, reaction temperature, and the amount of hydrogen peroxide, were investigated. Moreover, the Hammett acidity functions (H 0) of Brønsted acidic ionic liquids were determined using UV–visible spectrophotometry. The optimum reaction condition identified was n(H2WO4):n(Brønsted acidic ionic liquids):n(cyclohexene):n(H2O2) = 0.02:0.02:1:4.4, and the yield of adipic acid was 96% under the reaction scale of 10 mmol. The catalytic system can be easily recovered and reused for four reaction runs without significant loss of catalytic activity. Simple operation of the catalyst system and avoidance of the emission of nitrous oxide are the benefits of this work. 相似文献
18.
Laetitia Laversenne Christelle Goutaudier Rodica Chiriac Catherine Sigala Bernard Bonnetot 《Journal of Thermal Analysis and Calorimetry》2008,94(3):785-790
The hydrogen storage capabilities of alkaline borohydrides through a hydrolyzing process were determined by taking into consideration
the hydration of the end products. Comparison of LiBH4, NaBH4 and KBH4 showed their storage capacities to be dependent on the composition of the metaborate formed. This composition is ruled by
the hydrolysis conditions, especially the temperature reached during the reaction and the stability of the hydrates. The borohydride
with the highest hydrogen content in the solid state, LiBH4, could be less efficient than KBH4 if the hydrolysis is performed at 120°C. 相似文献
19.
Quanming Peng Guiming Peng Liangpeng Wu Xiaoyang Wang Xu Yang Xinjun Li 《Research on Chemical Intermediates》2018,44(11):6753-6763
In this study, we prepared nanoparticles of the visible light-responsive photocatalyst, Bi2O3 entrapped in anatase TiO2 nanotubes (Bi2O3-in-TNTs) via a vacuum-assisted precursor-filling process followed by annealing. Owing to the unique tubular electronic structure of TiO2 nanotubes, the interior of the nanotube is in an electron-deficient state, which was confirmed by XPS spectra and H2-TPR. Electrochemical impedance studies showed that the Bi2O3-in-TNTs demonstrated a more efficient separation of photogenerated carriers than when Bi2O3 nanoparticles were deposited on the outer wall of TiO2 nanotubes (Bi2O3-out-TNTs). Due to the confinement effect of TiO2 nanotubes, which inhibits photogenerated carriers’ recombination, the Bi2O3-in-TNTs exhibited a better photocatalytic performance for the photo-degradation of methyl orange under visible light compared to Bi2O3-out-TNTs. 相似文献
20.
E. G. Il’in A. S. Parshakov V. I. Privalov V. V. Danilov G. V. Bodrin E. I. Goryunov E. E. Nifant’ev 《Doklady Chemistry》2016,467(2):122-125
The composition and structure of the products of the reaction of titanium tetrafluoride with Ph2P(O)(CH2)2C(O)NМе2 (L), the simplest representative of diphenyl[2-(N,N-dialkylcarbamoyl)ethyl]phosphine oxides, in a СН2Сl2 have been studied by 19F and 31P NMR. It has been shown for the first time that functionalized phosphine oxides form stable seven-membered chelate heterocycles on complexes of d° transition metals. On the basis of NMR data, previously unknown conformational isomerism of the seven-membered TiOPCCCO heterocycle in solution has been proposed. A simple and rather efficient method of synthesis of the ligand (L) from commercially available reagents has been developed. 相似文献