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101.
Tangestaninejad S Moghadam M Mirkhani V Mohammadpoor-Baltork I Salavati H 《Ultrasonics sonochemistry》2008,15(5):815-822
Na5PV2Mo10O40 supported on nanoporous anatase TiO2 particles, TiO2–PVMo, was used as an efficient photocatalyst for photocatalytic degradation of different dyes by visible light using oxygen as oxidant. This catalyst showed a good catalytic activity in the sonocatalytic and sonophotocatalytic decomposition of different dyes in aqueous solutions. The TiO2–PVMo composite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure TiO2. 相似文献
102.
Sakhaii P Haase B Bermel W 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,191(2):291-303
A new scheme for obtaining HSQC spectra with improved resolution or in a shorter time called SHARC (Shaped Arrayed data aCquisition protocol) is proposed, which uses region selective RF pulses and allows the sweep width to be adjusted individually for each region. It thus bypasses the problems with the Nyquist theorem associated with other method suggested for this purpose. Assignment of the cross-peaks to their respective region is achieved by manipulating the phases of the RF pulses and/or their frequencies. SHARC NMR can be applied without any previous knowledge of the chemical shift distribution, but can be further optimized on the basis of a quick overview spectrum. 相似文献
103.
Structural Chemistry - Adsorption and reaction mechanisms for the noncovalent and covalent functionalization of SiO2 nanoparticle (SiNP) with gemcitabine (GEM) anticancer drug have been... 相似文献
104.
Anamalai K. Samylingam L. Kadirgama K. Samykano M. Najafi G. Ramasamy D. Rahman M. M. 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1533-1544
Journal of Thermal Analysis and Calorimetry - The emphasis of this paper is to evaluate the thermophysical properties of crystalline nanocellulose (CNC)-based nanofluid and the optimized machining... 相似文献
105.
A simple method is introduced providing a highly clean microextraction for the determination of some anti‐inflammatory drugs as the model analytes in human urine and environmental matrices. This method is based upon the implementation of two consecutive emulsification liquid‐phase microextractions, which are separated by a syringe filtration step. In this method, the organic extraction solvent (dihexyl ether) is dispersed into the aqueous sample solution (20 mL), and the resulting cloudy mixture is passed through a hydrophilic polytetrafluoroethylene syringe filter. By this action, the extraction phase containing the analytes and many interfering species that could be transferred into the organic phase is retained behind the hydrophilic membrane. The filter is then detached from the syringe and attached to another syringe containing an aqueous solution (pH 12.0, 150 μL), and by the in‐syringe dispersion of the organic phase into the aqueous phase, the analytes are selectively back‐extracted into the aqueous phase. The developed method is centrifuge‐free and very simple, and provides a high sample clean‐up in a few minutes. Under the optimized experimental conditions, the developed method provided a linearity in the range of 2.0–2000 ng/mL, a low limit of detection (0.5 ng/mL), and enrichment factors of 47–53. 相似文献
106.
Adam A. Y. Oumer A. N. Najafi G. Ishak M. Firdaus M. Aklilu T. B. 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2739-2768
Journal of Thermal Analysis and Calorimetry - The need for better thermal–hydraulic performance of heat exchangers remains the primary reason for further improving the design of heat... 相似文献
107.
108.
A novel approach using Monte Carlo method applied to simulation of low‐density polyethylene (LDPE) polymerization in tubular reactor showing topological characteristics, and the comprehensive kinetic mechanism has been taken into consideration. The results show the precise details of the structure of a chain in the three levels of the backbone, the main branches, and branches on branch. The chain types include dead polymer, dead polymer with unsaturated end, and live polymer with primary radical, secondary radical, and tertiary radical. In this work, the branches on branch were identified in terms of number, length, and position of the branch. Sixty percent of branches on branch are 1 to 5 carbons long, and the longest branch on branch is about 50 carbons. Thus, this study provides a tool for more accurately mapping the polymer chains architecture, superior to determine the number, and position of long‐ and short‐chain branches in past researches. Finally, this approach will advance the prediction of microstructure‐related properties of polymer one step further. 相似文献
109.
Mohamad Hasan Mohamadzadeh Moghadam Sina Sabury Mohsen Moazzami Gudarzi Farhad Sharif 《Journal of polymer science. Part A, Polymer chemistry》2014,52(11):1545-1554
Graphene oxide (GO)–polyaniline (PANI) composite is synthesized by in situ polymerization of aniline in the presence of GO as oxidant, resulting in highly crystalline and conductive composite. Fourier transform infrared spectrum confirms aniline polymerization in the presence of GO without using conventional oxidants. Scanning electron microscopic images show the formation of PANI nanofibers attached to GO sheets. X‐ray diffraction (XRD) patterns indicate the presence of highly crystalline PANI. The sharp peaks in XRD pattern suggest GO sheets not only play an important role in the polymerization of aniline but also in inducing highly crystalline phase of PANI in the final composite. Electrical conductivity of doped GO–PANI composite is 582.73 S m?1, compared with 20.3 S m?1 for GO–PANI obtained by ammonium persulfate assisted polymerization. The higher conductivity appears to be the result of higher crystallinity and/or chemical grafting of PANI to GO, which creates common conjugated paths between GO and PANI. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1545–1554 相似文献
110.
Maryam Mohebbi Peyman Salehi Morteza Bararjanian Samad N. Ebrahimi 《Journal of the Iranian Chemical Society》2018,15(1):47-53
In this paper, synthesis of two derivatives of noscapine and their application as organocatalysts in the asymmetric addition of diethylzinc to aromatic aldehydes is reported. The first catalyst (2) was synthesized by the reduction of lactone ring of noscapine to form the corresponding diol, and the second one (3) was prepared by tert-butyl dimethyl silylation of the primary hydroxyl group of 2. Excellent yields and high ees up to 95% were obtained by using 3 as the catalyst. To the best of our knowledge, this is the first report on the application of lactone ring opened noscapinoid compounds as organocatalysts in asymmetric reactions. 相似文献