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排序方式: 共有215条查询结果,搜索用时 15 毫秒
31.
The kinetics of multi-site phase transfer catalysed (MPTC) radical polymerisation of methyl methacrylate (MMA) using potassium peroxydisulphate (PDS) and synthesised 1, 4-Bis (tributyl methyl ammonium) benzene dichloride (TBMABDC) as multi-site phase transfer catalyst was investigated in cyclohexane–water two-phase system at constant temperature 60?±?1 °C under nitrogen circumstances. The role of concentrations of monomer, initiator, catalyst and volume fraction of aqueous phase, solvent polarity and temperature on the rate of polymerisation (Rp) was ascertained. The order with respect to monomer, initiator and phase transfer catalyst were found to be 0.80, 1.0 and 0.5, respectively. A suitable kinetic scheme has been proposed to account for the experimental observations and its significance is discussed. The prepared polymer was characterised by spectral analysis. 相似文献
32.
Gábor Blaskó Natesan Murugesan Alan J. Freyer Robert D. Minard Maurice Shamma 《Tetrahedron letters》1981,22(33):3143-3146
Fumaritridine and fumaritrine are not spirobenzylisoquinolines. Rather, they are indenobenzazepines so that fumaritridine is represented by expression and fumaritrine by . Treatment of dihydroparfumine () and dihydroparfumidine () uith trifluoroacetic anhydride folloued by quenching with methanol gives and , respectively. 相似文献
33.
This article reports an experimental investigation on the heat transfer, friction factor, and thermal enhancement factor of a tube equipped with vertical wing-cut twisted tapes, horizontal wing-cut twisted tapes, and plain twisted tapes with twist ratios of y = 2.0, 4.4, and 6.0. The obtained results reveal that the heat transfer rate, friction factor, and thermal enhancement factor in the tube equipped with horizontal wing-cut twisted tapes are significantly higher than those in the tube fitted with vertical wing-cut twisted tapes, plain twisted tapes, and a plain tube. An empirical correlation is subsequently derived from the experimental results. 相似文献
34.
Muthu Thangaraj Bibhuti Ranjan Ramesh Muthusamy Arul Murugesan Robert Moonsamy Gengan 《Journal of heterocyclic chemistry》2019,56(3):867-885
A series of fused quinolinyl and quinolonyl pyrans were synthesized via a one‐pot reaction of quinolinyl and quinolonyl carbaldehydes, malononitrile, and a 1,3‐diketone. The reactions were catalyzed by a new humic acid supported 1‐butyl‐3‐methyl imidazolium thiocyanate ionic liquid under microwave irradiation conditions. Antimicrobial, antioxidant, and toxicity studies displayed various biological activities depending on structure of the pyrans. 相似文献
35.
Sirigireddy Sudharsan Reddy Bhoomireddy Rajendra Prasad Reddy Peddiahgari Vasu Govardhana Reddy 《中国化学快报》2015,26(6):739-743
The Strecker reaction was performed via a one-pot three component condensation of hetero aromatic/aromatic aldehydes, secondary amines and trimetylsilyl cyanide in the presence of propylphosphonic anhydride(T3P~) to accomplish the corresponding a-aminonitriles. The main advantages of this method are very short reaction time and excellent yields. 相似文献
36.
Murugesan Dinesh Subramanyam Deepika Rajendran HarishKumar Chinnadurai Immanuel Selvaraj Selvaraj Mohana Roopan 《Applied biochemistry and biotechnology》2018,185(2):450-463
The current study indicates that octyl-β-D-glucopyranoside (OGP) as a detergent which has the ability to make the lipid layer stiff. OGP was subjected for toxicity studies and in vitro cytotoxicty assays on cancerous HeLa and non-cancerous myoblasts H9c2 cell lines. Test against aquatic organisms were carried out in Artemia salina and LC50 values were calculated. Hemolytic activity tested for blood bio-compalibity showed hemolysis rate of 10–16%, followed by thrombolytic activity to burst the clots in blood. Also, the samples showed good lysis when compared to the standard streptokinase. Furthermore, α-amylase activity has been carried out to check the inhibition of α-amylase by the OGP. Finally, antibacterial activity has been tested against four different pathogens and their MIC values have been calculated. 相似文献
37.
S. Vishnu Priya J. Herbert Mabel S. Gopalakrishnan M. Palanichamy V. Murugesan 《Journal of molecular catalysis. A, Chemical》2008,290(1-2):60-66
Magnesium aluminophosphate-36 (MAPO-36) molecular sieve was synthesised hydrothermally and subjected to wet ion-exchange with Fe3+, Zn2+, La3+ or Ce3+. They were characterised by using XRD, SEM, temperature programmed desorption (TPD) of ammonia and thermogravimetric analysis (TGA). The XRD patterns of ion-exchanged MAPO-36 exhibit similar features to that of MAPO-36, which revealed no structural degradation during ion-exchange. TPD (ammonia) showed selective ion-exchange of strong acid sites for Fe3+, La3+ and Ce3+ but not for Zn2+. Based on the results of TGA the actual species involved in the ion-exchange is suggested to be M(OH)2+, which upon calcination converted to MO+ where M is Fe3+, La3+ or Ce3+. tert-Butylation of phenol was carried out in the vapour phase as a probe reaction to examine the catalytic activity of MAPO-36 and ion-exchanged MAPO-36 molecular sieves. The ion-exchanged catalysts were found to be more active than the parent MAPO-36 and also showed higher selectivity to 4-tert-butylphenol. 相似文献
38.
Sundararaj Rubila Thottiam Vasudevan Ranganathan Kunnathur Murugesan Sakthivel 《Applied biochemistry and biotechnology》2016,180(8):1482-1496
The aim of the present investigation was to evaluate Zingiber officinale paste against Dalton’s lymphoma ascites (DLA)-induced tumours in Swiss albino mice. Experimental animals received Z. officinale paste (low dose 100 mg/kg bw and high dose 500 mg/kg bw) orally for eight alternative days. Treatment with Z. officinale paste showed significant increase in haemoglobin level and decrease in aspartate amino transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (γ-GT) level. Z. officinale paste reduced the inflammatory mediators and cytokine levels, such as inducible nitric oxide (iNOS), tumour necrosis factor level (TNF-α) and interleukin-1β (IL-1β). Treatment with Z. officinale paste also significantly increased the antioxidant enzyme level, such as superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione transferase (GST), and decreased the lipid peroxidation. Treatment also increased the vitamin C and E levels in treated animals compared with the DLA-bearing host. Histopathological studies also confirmed the protective influence of Z. officinale paste against DLA. The present study suggested that Z. officinale paste could be used as natural spice and a potent antitumour agent. 相似文献
39.
Kumar A Pushparaj VL Murugesan S Viswanathan G Nalamasu R Linhardt RJ Nalamasu O Ajayan PM 《Langmuir : the ACS journal of surfaces and colloids》2006,22(21):8631-8634
We demonstrate the one-step synthesis of a silica-gold nanocomposite by simultaneous hydrolysis and reduction of gold chloride. The aminophenyl group was used as a reducing agent, and the trimethoxy silane group acts a precursor for the formation of silica. The porous gold nanoparticles were formed by etching out the silica-gold nanocomposite by hydrofluoric acid. The electron diffraction of porous gold nanoparticles showed that the particle are polycrystalline with FCC structure. The silica-gold nanocomposite exhibited nonlinear current-voltage behavior, and the porous gold nanoparticles displayed linear current-voltage behavior. 相似文献
40.
G. Balakrishnan P. Kuppusami S. Murugesan E. Mohandas D. Sastikumar 《Crystal Research and Technology》2012,47(4):415-422
Zirconium oxide thin films have been deposited on Si (100) substrates at room temperature at an optimized oxygen partial pressure of 3x10‐2 mbar by reactive pulsed laser deposition. High temperature x‐ray diffraction (HTXRD) studies of the film in the temperature range room temperature‐1473 K revealed that the film contained only monoclinic phase at temperatures ≤ 673 K and both monoclinic and tetragonal phases were present at temperatures ≥ 773 K. The tetragonal phase content was significantly dominating over monoclinic phase with the increase of temperature. The phase evolution was accompanied with the increase in the crystallite size from 20 to 40 nm for the tetragonal phase. The mean thermal expansion coefficients for the tetragonal phase have been found to be 10.58x10‐6 K‐1 and 20.92x10‐6K‐1 along a and c‐axes, respectively. The mean volume thermal expansion coefficient is 42.34x10‐6 K‐1 in the temperature range 773‐1473 K. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献