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排序方式: 共有273条查询结果,搜索用时 31 毫秒
21.
Bamoharram Fatemeh F Roshani Mina Heravi Majid M Mahdavi Masoumeh Javid Ali Emampour Jalal Sh 《中国化学》2010,28(6):974-976
Isoxazolo[5,4‐d]pyrimidine‐4,6(5H,7H)diones 2a – 2f have been synthesized from the reaction of ethyl 5‐amino‐3‐methyl‐4‐isoxazole carboxylate ( 1 ) with aryl isocyanates in the presence of Keggin heteropolyacid H3[PW12O40] as a green solid acid catalyst at room temperature in a one‐pot process in good yields. 相似文献
22.
Cyanide detection in pure water is important for many applications. We present a novel type of chemodosimeter azo dye developed on the basis of the benzophenone as the electrophilic receptor of the cyanide anion and a saccharidic moiety to render the dye water soluble. This chemodosimeter is found to be highly selective and tunable toward only cyanide in pure water. 相似文献
23.
Jalal Ghilane Pascal Martin Hyacinthe Randriamahazaka Jean-Christophe Lacroix 《Electrochemistry communications》2010,12(2):246-249
Electrochemical oxidation of primary amine in ionic liquid media has been investigated. The ionic liquid chosen for this study was 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. Two primary amine compounds are used for this study; 4-nitrobenzylamine and 2-aminoethylferrocenylmethylether. The oxidation of the amino compounds in ionic liquid conduces to the modification of the electrode surface. The modified electrodes were characterized by cyclic voltammetry and XPS analysis. Both techniques support the presence of an organic layer strongly attached onto the electrode surface. The surface concentration of the attached group obtained in this media was found to be around 1 to 3 × 10?10 mol cm?2. The use of ionic liquid as media for the grafting leads to decrease of the surface concentration of the grafted layer; and the formation of less dense layer compared with classical solvent such as acetonitrile. 相似文献
24.
Luís Santos Pascal Martin Jalal Ghilane Pierre-Camille Lacaze Hyacinthe Randriamahazaka Luisa Maria Abrantes Jean-Christophe Lacroix 《Electrochemistry communications》2010,12(7):872-875
The electrodeposition of poly(3,4-ethylenedioxythiophene) (PEDOT) films from aqueous surfactant solution through a two-dimensional poly(styrene) (PS) template onto indium tin oxide (ITO) substrate has been investigated. The polymer grows in the interstitial spaces of the self-assembled PS spheres which were subsequently removed by dissolution in tetrahydrofuran (THF). Surface characterization by scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveals that two-dimensional nanoporous honeycomb PEDOT structures can easily be obtained by using PS spheres of different sizes. Gold electrodeposition onto the nanostructured PEDOT electrode was investigated and SEM images show preferential formation of nanoparticles (NP) on the wall and the rim of the PEDOT film but metal clusters inside the pores are also observed. 相似文献
25.
The nanocatalyst-assisted sonodegradation of Basic Blue 41 (BB41) dye in aqueous medium was modeled and optimized using response
surface method (RSM) based on Box-Behnken design. The studied variables included pH, initial dye concentration, H2O2 concentration and sonolysis time while each factor varied at three levels: Low level (−1), Medium level (0) and High level
(+1). The ultrasound -assisted degradation was well described by developing quadratic model with correlation value squared
(R2) of 0.9114. Factor effects along with interaction effects were evaluated. The graphical optimization step was conducted to
achieve the best experimental condition in dye removal. pH, H2O2 concentration and initial dye concentration of the reaction were investigated. It was recognized that at lower pH values
the dye removal rate decreased. However, dye removal rate increased (82.5%) by increasing the concentration of H2O2 and by lowering the initial dye concentration.
相似文献
26.
Seyed Jalal Hosseinimehr Amirhossein Ahmadi Reza Taghvai 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(3):563-566
Free radicals and oxidative stress are the primary causes of several chronic diseases such as cancer and heart disease. Quercetin
is a natural compound with potent antioxidant activity. We have prepared and evaluated technetium-99m (99mTc)-labeled quercetin as a potential radical scavenging radiotracer. A 99mTc-quercetin complex was prepared using quercetin, SnCl2 and Na99mTcO4 in a buffered solution over 30 min. The participation coefficient was measured in octanol and queues solutions. The stability
was determined in phosphate buffered saline and serum. The biodistribution in normal mice was evaluated at 0.5, 2, 6 and 24 h
post-injection. The radiochemical purity (>99%) was determined by thin layer chromatography (TLC) in normal saline solution
as the mobile phase. It has a log P of 0.204. It was mainly cleared by the kidneys and showed negligible brain uptake at four time points measured post-injection.
The pharmacological properties of quercetin, mainly its free radical scavenging, may potentially cat as a radiopharmaceutical
agent for radical-targeted imaging of tissue with high levels of reactive oxygen species. 相似文献
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29.
M. Sohani M. R. Housaindokht R. Jalal H. Eshtiagh-Hosseini A. Hassanpoor Z. Rouhbakhsh Zaeri 《Journal of the Iranian Chemical Society》2017,14(6):1309-1316
A new cobalt (II) coordination compound was synthesized using proton transfer mechanism. The reaction between CoCl2·2H2O, Salicylic acid (H2Sal) and acridine (Acr) gave a new coordination compound formulated as (HAcr)4[Co(Sal)3], which was characterized by elemental analysis, NMR, IR and UV/Vis spectroscopies. The interaction of this complex with DNA has been investigated in vitro using UV absorption, fluorescence spectroscopy, viscosity measurements and gel electrophoresis methods. The intrinsic binding constant has been estimated to be 5.8 × 105 M?1 using UV absorption. The interaction of DNA–Co (II) complex caused quenching in fluorescence. The binding constant, the number of binding site and Stern–Volmer quenching constant have been calculated to be 7.7 × 104 M?1, 1.143 and 1.5 × 104 Lmol?1, respectively. The increase in the viscosity of DNA with increasing the concentration of the Co (II) complex and the observations of other experiments suggest that the cobalt (II) complex binds to DNA by partial intercalation binding mode. Furthermore, the interaction of DNA–Co (II) complex was confirmed using gel electrophoresis studies. Moreover, molecular docking technique predicted partial intercalation binding mode for the complex. 相似文献
30.
Jingwei Liang Jalal Fadili Gabriel Peyré 《Journal of Optimization Theory and Applications》2017,172(3):874-913
The Douglas–Rachford and alternating direction method of multipliers are two proximal splitting algorithms designed to minimize the sum of two proper lower semi-continuous convex functions whose proximity operators are easy to compute. The goal of this work is to understand the local linear convergence behaviour of Douglas–Rachford (resp. alternating direction method of multipliers) when the involved functions (resp. their Legendre–Fenchel conjugates) are moreover partly smooth. More precisely, when the two functions (resp. their conjugates) are partly smooth relative to their respective smooth submanifolds, we show that Douglas–Rachford (resp. alternating direction method of multipliers) (i) identifies these manifolds in finite time; (ii) enters a local linear convergence regime. When both functions are locally polyhedral, we show that the optimal convergence radius is given in terms of the cosine of the Friedrichs angle between the tangent spaces of the identified submanifolds. Under polyhedrality of both functions, we also provide conditions sufficient for finite convergence. The obtained results are illustrated by several concrete examples and supported by numerical experiments. 相似文献