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排序方式: 共有117条查询结果,搜索用时 62 毫秒
51.
Manoj Vanaraja Karthika Muthukrishnan Shanmugam Boomadevi Rakesh Kumar Karn Vijay Singh Pramod K. Singh 《Phase Transitions》2016,89(2):107-114
TiO2 thin film was fabricated by dip coating method using titanium IV chloride as precursor and sodium carboxymethyl cellulose as thickening as well as capping agent. Structural and morphological features of TiO2 thin film were characterized by X-ray diffractometer and field emission scanning electron microscope, respectively. Crystallinity of the film was confirmed with high-intensity peak at (101) plane, and its average crystallite size was found to be 28 nm. The ethanol-sensing properties of TiO2 thin film was studied by the chemiresistive method. Furthermore, various gases were tested in order to verify the selectivity of the sensor. Among the several gases, the fabricated TiO2 sensor showed very high selectivity towards ethanol at room temperature. 相似文献
52.
Withanolides, the secondary metabolite from Withania species is used in Ayurvedic medicine and now proved to have potential use in treating cardiovascular, Alzheimer’s disease, etc. Its production in plants varies between genotypes with very low yield. For improved industrial commercialisation, there is a need to increase its production. Endophytic fungi are symbiotically associated with plants and can synthesise the same bioactive compounds and natural products as their host plant. There are no reports available on withanolide-producing (endophytic) fungi. The present study identified an endophytic fungus (Taleromyces pinophilus) from leaves of Withania somnifera which produces withanolides in the medium. The structure of withanolide was confirmed by 1H NMR, LC-MS analyses and quantified by HPLC analysis. The fungus produces high amount of withanolide when compared to leaf and root of W. somnifera. The fungus can be exploited to produce the withanolide to meet its demand. 相似文献
53.
I. C. Pius M. M. Charyulu C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1994,187(1):57-65
Distribution ratios of Pu(IV) between 7.5M HNO3+0.75M H3PO4+0.3M H2SO4 media and a macroporous anion-exchange resin Amberlyst A-26 (MP) increased from 40 to 250 when 1M aluminium nitrate was added to the aqueous medium. When 1M ferric nitrate was used in place of aluminium nitrate the distribution ratio further increased to 850. The 10% Pu(IV) breakthrough capacities with a 5 ml bed resin column, using synthetic feed solutions containing 1M aluminium nitrate, were 1.4 g l–1, 3.2 g l–1 at flow rates of 30 ml per hour and 10 ml per hour, respectively. The corresponding 10% Pu(IV) breakthrough capacities in the presence of 1M ferric nitrate were 8.5 g l–1 and 12.8 g l–1. More than 97% of plutonium could be recovered from actual analytical phosphate waste solutions. 相似文献
54.
V. B. Sagar M. S. Oak S. M. Pawar C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1990,139(1):121-126
A method for the recovery and purification of233U from phosphate containing analytical waste is developed. Extraction studies with DBDECMP (Di-butyl, N, N-diethylcarbamoyl-methyl phosphonate) in xylene were carried out to explore the feasibility of separation and purification of233U from such wastes. Based on the data obtained, optimum conditions for the recovery of233U are suggested. 相似文献
55.
Vedagiri Hemamalini Dass Prakash M. Velayutham Loganathan Lakshmanan Karthikeyan Muthusamy Sivaperumal Sivaramakrishnan 《Natural product research》2020,34(11):1591-1596
AbstractHydroxychavicol (HC), a major phenolic derivative isolated from the leaves of Piper betle L. is well known for its antibacterial, antifungal and antimutagenic properties. The present study evaluated the in vivo antitumor activity of HC against Ehrlich Ascites Carcinoma (EAC) cells in Swiss albino mice and in silico interaction of HC with the receptors involved in the cancer. Hydroxychavicol (200 and 400?mg/kg bw) was orally administered for 21 consecutive days and was effective in inhibiting the tumor growth in ascitic mouse model. HC consistently reduced the tumor volume, viable cell count, lipid peroxidation and elevated the life span of HC treated mice. Besides the hematological profiles, SGOT and SGPT levels reverted back to normal and oxidative stress markers GSH, SOD and CAT also increased in HC treated groups. In silico docking analysis revealed that HC possessed potent antagonist activity against all the cancer targets demonstrating its inhibitory activity. 相似文献
56.
M. Muthukrishnan Shivaji V. More Dinesh R. Garud C. V. Ramana R. R. Joshi R. A. Joshi 《Journal of heterocyclic chemistry》2006,43(3):767-772
1,2,3,4‐Tetrahydro‐β‐carbolines have been synthesized in moderate to good yields in short reaction time using the ionic liquid [bbim] BF4 as reaction medium and promoter. There was no need for the use of an additional catalyst normally employed in Pictet‐Spengler condensation. 相似文献
57.
Zhou M Sivaramakrishnan A Ponnamperuma K Low WK Li C Liu JO Bergbreiter DE Romo D 《Organic letters》2006,8(23):5247-5250
[Structure: see text] The synthesis and characterization of thermoresponsive, water-soluble poly-N-isopropyl acrylamide (PNIPAM) derived macroligands displaying cyclosporin A (CsA) and dexamethasone (Dex) for use as novel affinity resins are described. Characterization of these soluble macroligands, including ligand loading and integrity, was determined by 1H NMR spectroscopy. One of the CsA macroligands was used in a protein affinity experiment to capture known binding proteins of CsA, the cyclophilins, from Jurkat T-cell lysates. 相似文献
58.
Mandel SM Singh PN Muthukrishnan S Chang M Krause JA Gudmundsdóttir AD 《Organic letters》2006,8(19):4207-4210
Solid-state photolysis of 1 yields 2 in a crystal-to-crystal reaction. The reaction takes place by alpha-cleavage to form a benzoyl and an azido alkyl radical pair. The azido alkyl radicals rearrange into iminyl radicals and N2. The iminyl and benzoyl radicals are held in close proximity within the crystal lattice, which allows them to combine and form 2. X-ray structure analysis, molecular modeling and trapping studies support this mechanism. 相似文献
59.
Sharmila Muthukrishnan Akhilesh Tanwar Sharankumar G. Shetty Pradeep Singh Yogesha Subbaiah Arun Sikder Radha Kamalakaran Bander Al-Farhood 《Polymer Science Series A》2018,60(3):350-358
In the present study, we have investigated the miscibility, morphology and mechanical behavior of poly(methyl methacrylate) (PMMA) blends with a series of poly(styrene-co-maleic anhydride) (SMA) copolymers containing varying amounts of maleic anhydride (MA) content (from 8 to 26%). The experimental findings have been substantiated by the modeling studies to gain fundamental understanding of the observed phenomena with respect to the miscibility of the PMMA and SMA blends of a given MA content. The morphological differences, molecular weights, domain sizes and mechanical behavior of the blends at a given ratio of PMMA and copolymers have been investigated and a correlation has been made between the morphological understanding to the molecular weights and mechanical properties. The results indicate that the PMMA/SMA blends are miscible only at a certain MA content providing transparent PMMA/SMA blends without affecting any of the enabling properties of PMMA that are of commercial interest through a facile melt mixing process. The surface hardness and % recovery (nano-indentation) of these blends were evaluated as well to gain fundamental understanding of the surface characteristics and mechanicals of the blends. 相似文献
60.
Alex Krisman Christine Mounaïm-Rousselle Raghu Sivaramakrishnan James A. Miller Jacqueline H. Chen 《Proceedings of the Combustion Institute》2019,37(2):1631-1638
Laminar natural gas flames are investigated at engine-relevant thermochemical conditions where the ignition delay time τ is short due to very high ambient temperatures and pressures. At these conditions, it is not possible to measure or calculate well-defined values for the laminar flame speed sl, laminar flame thickness δl, and laminar flame time scale due to the explosive thermochemical state. Here, the corresponding reference values, sR, δR, and that account for the effects of autoignition, are numerically estimated to investigate the enhancement of flame propagation, and the competition with autoignition that arises under nominally autoignitive conditions (characterised here by the number τ/τR). Large values of τ/τR indicate that autoignition is unimportant, values near or below unity indicate that flame propagation is not possible, and intermediate values indicate that a combination of both flame propagation and autoignition may be important, depending upon factors such as device geometry, turbulence, stratification, et cetera. The reference quantities are presented for a wide range of temperatures, equivalence ratios, pressures, and hydrogen concentrations, which includes conditions relevant to stationary gas turbine reheat burners and boosted spark ignition engines. It is demonstrated that the transition from flame propagation to autoignition is only dependent on residence time, when the results are non-dimensionalised by the reference values. The temporal evolution of the reference values are also reported for a modelled boosted SI engine. It is shown that the nominally autoignitive conditions enhance flame propagation, which may be an ameliorating factor for the onset of engine knock. The calculations are performed using a recently-developed, detailed 177 species mechanism for C0–C3 chemistry that is derived from theoretical chemistry and is suitable for a wide range of thermochemical conditions as it is not tuned or optimised for a particular operating condition. 相似文献