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131.
Nasser Iranpoor Habib Firouzabadi Dariush Khalili Rezvan Shahin 《Tetrahedron letters》2010,51(27):3508-1435
Highly regioselective thiocyanations of indoles, anilines and pyrrole are achieved via an efficient and simple protocol using NH4SCN and diethyl azodicarboxylate (DEAD) as a mild oxidant. 相似文献
132.
In this work, palladium complexes nanoparticles in titania are prepared by a pH‐controlled adsorption and without pH‐controlled adsorption method. This method results in high‐dispersion palladium on the titania surface. We demonstrate the use of the titania‐supported palladium as an efficient catalyst for Suzuki and Heck reactions of a representative range of aryl bromides and chlorides. The reusability of catalyst was tested, and deactivation process of the catalyst was not observed after four recycles. The catalysts were characterized by FT‐IR, NMR, elemental analysis, field emission scanning electron microscopy, transmission electron microscopy and X‐ray diffraction. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
133.
Mashaghi A Partovi-Azar P Jadidi T Nafari N Maass P Tabar MR Bonn M Bakker HJ 《The Journal of chemical physics》2012,136(11):114709
We investigate the structure and electronic properties of phosphatidylcholine (PC) under different degrees of hydration at the single-molecule and monolayer type level by linear scaling ab initio calculations. Upon hydration, the phospholipid undergoes drastic long-range conformational rearrangements which lead to a sickle-like ground-state shape. The structural unit of the tilted gel-phase PC appears to be a water-bridged PC dimer. We find that hydration dramatically alters the surface potential, dipole and quadrupole moments of the lipids and consequently guides the interactions of the lipids with other molecules and the communication between cells. 相似文献
134.
Ghasem Soleimani Rad Hassen Aydi Poom Kumam Hamidreza Rahimi 《Rendiconti del Circolo Matematico di Palermo》2014,63(2):287-300
In this paper, we prove some common tripled fixed point and tripled coincidence point results for contractive conditions in a cone metric type space. Our results extend, unify and generalize well-known results in the literature, in particular the recent results of Aydi et al. (Fixed Point Theory Appl 2012:134, 2012). Some examples are also presented to validate our obtained results and new concepts. 相似文献
135.
We investigate the amenability of the semigroup algebras \({\ell^1(S/\rho)}\) , where \({\rho}\) is a group congruence (not necessarily minimal) on a semigroup S. We relate this to a new notion of amenability of Banach algebras modulo an ideal, to prove a version of Johnson’s theorem for a large class of semigroups, including inverse semigroups, E-inversive semigroup and E-inversive E-semigroups. 相似文献
136.
Morteza Hosseini Hayedeh Bagheri Sadeghi Mohammad Rahimi Masoud Salavati‐Niasari Shiva Dehghan Abkenar Kamal Alizadeh Mohammad Reza Ganjali 《Electroanalysis》2009,21(7):859-866
Studies on complex formation of tris(3‐(2‐hydroxybenzophenone)propyl)amine (THPA) with a number of metal ions in acetonitrile solution revealed the occurrence of a selective 1 : 1 complexation of the proposed ligand with Sn2+ ion. Consequently, THPA was used as a suitable neutral ionophore for the preparation of a polymeric membrane‐selective electrode. The electrode exhibits a Nernstian behavior with a slope of 29.4±0.3 mV per decade and a detection limit of 2.0×10?7 M. It also showed a good selectivity for Sn2+ ions in comparison with some of group A and B metal ions over a wide concentration range of 5.0×10?7–1.0×10?1 M. Improved selectivity was achieved compared to the best selectivity recently reported by other authors for tin(II). The electrode was successfully applied to the determination of Sn2+ ion in waste water and various canned products. 相似文献
137.
In this article our aim was to evaluate mass cultivation of S. marianum hairy roots in a bioreactor to produce silymarin. The effects of methyl jasmonate (MJ) elicitation on the accumulation of silymarin and the extent of the MJ-induced oxidative damage were investigated in bioreactor hairy root cultures of S. marianum. The growth rate of the bioreactor hairy root cultures was higher than that of those in a shake flask after 3 weeks. Silymarin accumulation was increased from 0.13?mg?g?1 DW in non-treated hairy roots to 0.22?mg?g?1 DW in hairy roots 72?h after 100?μM?MJ treatment. Guaiacol peroxidase and ascorbate peroxidase were activated by MJ?72?h after treatment, being 3.2- and 1.3-fold higher, respectively, than that of the control. An increase in enzymatic activity suggests increased scavenging of reactive oxygen species, indicating the tolerance to MJ stress. These results suggest that MJ elicitation is beneficial for silymarin production using bioreactor hairy root cultures. 相似文献
138.
Dr. Shigeaki Nakazawa Dr. Shinsuke Nishida Dr. Tomoaki Ise Dr. Tomohiro Yoshino Dr. Nobuyuki Mori Dr. Robabeh D. Rahimi Prof. Dr. Kazunobu Sato Prof. Dr. Yasushi Morita Dr. Kazuo Toyota Prof. Dr. Daisuke Shiomi Prof. Dr. Masahiro Kitagawa Dr. Hideyuki Hara Dr. Patrick Carl Dr. Peter Höfer Prof. Dr. Takeji Takui 《Angewandte Chemie (International ed. in English)》2012,51(39):9860-9864
139.
We investigate the transmission properties of one-dimensional Fibonacci quasiperiodic structure consisting of dispersive and
lossless epsilon-negative (ENG) materials. It is found that for both TE and TM polarizations with normal and oblique incidences,
there exist transmission gaps which are invariant with a change of scale and sensitive to incident angles. Analytical methods
based on transfer matrices and effective medium theory have been used to explain the properties of transmission gaps. 相似文献
140.
A flow injection procedure for the sequential spectrophotometric determination of iron(II) and iron(III) in pharmaceutical products is described. The method is based on the catalytic effect of iron(II) on the oxidation of iodide by bromate at pH = 4.0. The reaction was monitored spectrophotometrically by measuring the absorbance of produced triiodide ion at 352 nm. The activating effect for the catalysis of iron(II) was extremely exhibited in the presence of oxalate ions, while oxalate acted as a masking agent for iron(III). The iron(III) in a sample solution could be determined by passing through a Cd-Hg reductor column introduced in the FIA system to reduce iron(III) to iron(II), which allows total iron determination. Under the optimum conditions, iron(II) and iron(III) could be determined over the range of 0.05 - 5.0 and 0.10 - 5.0 microg ml(-1), respectively with a sampling rate of 17 +/- 5 h(-1). The experimental limits of detection were 0.03 and 0.04 microg ml(-1) for iron(II) and iron(III), respectively. The proposed method was successfully applied to the speciation of iron in pharmaceutical products. 相似文献