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1.
It has come to our attention that this article, “Rheology, Morphology, and Estimation of the Interfacial Tension of Binary Blends Based on Low‐Density Polyethylene/Poly(trimethylene terephthalate) and High‐Density Polyethylene/Poly(trimethylene terephthalate)” by A. A. Shokri and S. E. Zamani was previously published under the title, “Rheology, Morphology and Estimation of Interfacial Tension of LDPE/EVA and HDPE/EVA Blends” by H. A. Khonakdar, S. H. Jafari, A. Yavari, A. Asadinezhad, U. Wagenknecht, in Polymer Bulletin 54, 75–84 (2005), . We have retracted the article, and offer our apologies to the authors of the original paper. 相似文献
2.
Experimental and Theoretical Study of the Effect of Moisture on Methane Adsorption and Desorption by Activated Carbon at 273.5 K
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Adsorption and desorption of methane by activated carbon (AC) at constant temperature and at various pressures were investigated. The effect of moisture was also studied. A volumetric method was used, up to 40 bar, at a temperature of 273.5 K. Results of a dry AC sample were compared with those obtained from a moist sample and two different ACs with different physical and surface properties were used. As expected, the results showed that the existence of moisture, trapped in the AC pores, could lead to a decrease in the amount of methane adsorbed and a decrease in the amount of methane delivered during desorption. To model the experimental results, a large variety of adsorption isotherms were used. The regressed parameters for the adsorption isotherms were obtained using the experimental data generated in the present study. The accuracy of the results obtained from the different adsorption isotherms was favorably compared. 相似文献
3.
Some new N‐glycosides of 4‐(2‐phenylethyl)‐5‐pyridyl‐1,2,4‐triazole‐3‐thiones were synthesised by the coupling reaction of halo sugar with 4,5‐disubstituted 3H‐1,2,4‐triazole‐3‐thiones in the presence of mercuric cyanide and dry nitromethane as solvent, followed by deprotection using dry ammonia in methanol. All of the above compounds were fully characterized by means of infrared, 1H NMR spectroscopy, mass spectroscopy and elemental analysis. 相似文献
4.
Raissi H Nowroozi A Farzad F Bojd MS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(1-3):343-352
Fourier transform infrared and Fourier transform Raman spectra of Cu(II) bis-acetylacetone have been obtained. The geometry, frequency and intensity of the vibrational bands of this compound and its 1,5-(13)C(2), 3-(13)C, 1,3,5-(13)C(3), 2,4-(13)C(2), (18)O(2) and 2,4-(13)C(2)-(18)O(2) derivatives were obtained by the density functional theory (DFT) with the B3LYP functional and using the 6-31G(*) and 3-21G(*) basis sets. The calculated frequencies are compared with the solid infrared and Raman spectra. All the measured infrared and Raman bands were interpreted in terms of the calculated vibrational modes. The percentage of deviation of the bond lengths and bond angles gives a good picture of the normal modes, and serves as a basis for the assignment of the wavenumbers. Most computed bands are predicted to be at higher wavenumbers than the experimental bands. The calculated geometrical parameters show slight differences compared with the experimental results. These differences can be explained by the different physical state of Cu(II) bis-acetylacetone. The DFT-B3LYP calculations assumed a free molecule in the gas phase. Analysis of the vibrational spectra indicates a strong coupling between the chelated ring modes. 相似文献
5.
A variety of alcoholic TBDMS (t-butyldimethylsilyl) ethers are easily removed in excellent yields by treatment with a catalytic amount of N-iodosuccinimide (NIS, 5 mol %) in methanol. This method is able to deprotect TBDMS ethers of alcohols in the presence of TBDMS ethers of phenols. 相似文献
6.
Jantunen KC Haftbaradaran F Katz MJ Batchelor RJ Schatte G Leznoff DB 《Dalton transactions (Cambridge, England : 2003)》2005,(18):3083-3091
The high-yield synthesis, spectroscopic and structural determination of three new uranium(IV) and thorium(IV)ate complexes supported by three different diamido ether ligands are reported. The reaction of Li2[2,6-iPr2PhN(CH2CH2)]2O (Li2[DIPPNCOCN]) with 1 equiv. of UCl4 in THF generates [DIPPNCOCN]UCl3Li(THF)2(1), while reaction in toluene/ether gives salt-free [DIPPNCOCN]UCl2.1/2C7H8(2), which was identified by paramagnetically shifted 1H NMR. Reaction of 0.5 equiv. of {[tBuNON]UCl2}2([tBuNON]=[(CH3)3CN(Si(CH3)2)]2O2-) with 3.5 equiv. LiI in toluene and a minimal amount of THF results in [tBuNON]UI3Li(THF)2(3) and is very similar in structure to 1. {[MesNON]ThCl3Li(THF)}2(4), a dimeric complex with a Th2Li2Cl6 core, is prepared by reaction of Li2[2,4,6-Me3PhN(Si(CH3)2)]2O (Li2[MesNON]) with ThCl4 in THF. The analogous reaction in toluene did not yield the salt-free complex but rather a sterically crowded diligated compound, [MesNON]2Th (5), which was also structurally characterized. Complex 5 was prepared rationally by reacting 2 equiv. Li2[MesNON] with ThCl4 in toluene. The reaction of 1 and 3 with 2 equiv. of LiCH2Si(CH3)3 generates the stable, salt-free organoactinides [DIPPNCOCN]U(CH2Si(CH3)3)2(6) and [tBuNON]U(CH2Si(CH3)3)2(7). Complex 6 was structurally characterized. These reactions illustrate the viability of ate complexes as useful synthetic precursors. 相似文献
7.
Structural Chemistry - In this study, density functional theory (DFT) was employed to predict thermochemical and energetic properties for single-walled carbon nanotubes (SWCNTs) decorated with one... 相似文献
8.
Alamdarlo Farzad Vaziri Solookinejad Ghahraman Zahakifar Fazel Jalal Masoud Rezvani Jabbari Masoud 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):1033-1043
Journal of Radioanalytical and Nuclear Chemistry - In this work, graphene oxide (GO) and (aminomethyl)phosphonic acid–Graphene oxide (AMPA–GO) adsorbents were prepared by the modified... 相似文献
9.
Dispersion-corrected density functional theory method was performed to report on a high-performance adsorbent for removal of CO2 from the precombustion and natural gases. At first, the effect of Al atom impurity on the structural and electronic properties of B80 fullerene is studied. Then, the adsorption geometries and energies of gases (H2, CH4, or CO2) on the B80 and AlB79 (amphoteric adsorbents) are explored. The Al atom enhances reactivity of the cage toward the gases and the adsorption processes are more exothermic with low and high energy barriers for chemisorption of H2 and CO2, respectively. Stable chemisorption of CO2 on the AlB79 is validated by the high adsorption energy and large charge transfer, while the CH4 is just physically adsorbed on the AlB79. Further, the physisorbed gases can enhance field emission current of the AlB79 and in the continuous capturing of the gases, the magnetic moment of the cage is quenched. Furthermore, dependency of the electronic structure of the adsorbent on the gas adsorption is intensively studied. We suggest that the AlB79 could be a promising material for capture, storage, and separation of the gases and as a novel material for sustainable energy and sweetening process in the petroleum industry. 相似文献
10.
Sai Kumar Chakka Zamani E.D. Cele Sphelele C. Sosibo Vivian Francis Per I. Arvidsson Hendrik G. Kruger Glenn E.M. Maguire Thavendran Govender 《Tetrahedron: Asymmetry》2012,23(8):616-622
A series of novel TIQ based N,N′-oxide ligands were synthesised and screened for their catalytic activity in the enantioselective conjugate addition of thioglycolate to chalcones. Bulky groups on the side chain of the TIQ backbone provided the highest enantioselectivity of up to 88% with 10 mol % catalyst loading. It was also observed that these reactions proceeded optimally in the presence of dichloromethane as a solvent. Screening of various metals emphasized La(OTf)3 as the ideal pre-catalyst for this particular reaction. 相似文献