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341.
Pramod K. Sharma 《Archiv der Mathematik》1981,37(1):325-329
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344.
Pratima Bajpai Pramod K. Bajpai Owen P. Ward 《Applied biochemistry and biotechnology》1991,31(3):267-272
Mortierella alpina ATCC 32222 grew well at 11 degrees C, as well as at 25 degrees C in a liquid medium containing glucose or linseed oil and yeast extract. High Eicosapentaenoic acid (EPA) yield was obtained at 11 degrees C. M. alpina cells did not produce EPA at 25 degrees C in the absence of linseed oil, whereas at 11 degrees C, EPA accumulation was noted in the absence of linseed oil. When grown at 11 degrees C for 10 d in a medium containing 2% linseed oil as carbon source, the mycelium yielded 435 mg/L EPA (20 mg EPA/g dry mycelia) with 5.1% in lipid fraction. By gradually increasing the concentration of linseed oil to 4%, yield of biomass and EPA were increased to 43 g/L and 596 mg/L, respectively. 相似文献
345.
Kurian A Unnikrishnan KP George DS Gopinath P Nampoori VP Vallabhan CP 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(3):487-491
The wavelength dependence of thermal lens signal from organic dyes are studied using dual beam thermal lens technique. It is found that the profile of thermal lens spectrum widely differ from the conventional absorption spectrum in the case of rhodamine B unlike in the case of crystal violet. This is explained on the basis of varying contribution of nonradiative relaxations from the excited vibronic levels. 相似文献
346.
The general methods, photoinitiated or peroxide-initiated free radical chain additions of halomethanes to olefins, yield 1,2-addition products at temperatures ranging from 20 to 100 degrees C. At lower temperatures, -42 to -104 degrees C, a competitive reaction, subsequent to the addition of CCl(2)X(*), yields alkylcyclopropanes. The reactions of 1-octene or 1-hexene and 1-methylcyclohexene with atomic hydrogen carried out in the presence of several transfer agents (CCl(4), CCl(3)Br, CCl(2)Br(2)) initiate a radical chain addition of CCl(2)X(*) and yield cyclized materials resulting from the S(H)i displacement of halogen by a carbon-centered radical. The radical displacement of a halogen on carbon, the reverse of homolytic displacement on cyclopropyl carbon, is dominant at low temperatures. The rate constants for cyclization (k(c)) vs transfer with halomethane (k(t)) showed isokinetic temperatures of -46 degrees C (CCl(4), 1-hexene); -35 degrees C (CCl(4), 1-methylcyclohexene). The isokinetic temperatures for the reactions of the two substrates carried out in the presence of BrCCl(3) were calculated as -204 degrees C (1-octene) and -109 degrees C (1-methylcyclohexene). 相似文献
347.
Rajib K. Mitra Dr. Pramod K. Verma Dirk Wulferding Dirk Menzel Dr. Tamoghna Mitra Dr. Ana M. Todea Dr. Peter Lemmens Prof. Dr. Achim Müller Prof. Dr. Samir K. Pal Dr. 《Chemphyschem》2010,11(2):389-393
The effect of confinement and energy transfer on the dynamics of a molecular magnet, known as a model system to study quantum coherence, is investigated. For this purpose the well‐known polyoxovanadate [V15As6O42(H2O)]6? (V15) is incorporated into a protein (human serum albumin, HSA) cavity. Due to a huge overlap of the optical absorption spectrum of V15 with the emission spectrum of a fluorescence center of HSA (containing a single tryptophan residue), energy transfer is induced and probed by steady‐state and time‐resolved fluorescence. The geometrical coordination and the distance of the confined V15 to the tryptophan moiety of HSA are investigated at various temperatures. This effect is used as a local probe for the thermal denaturation of the protein at elevated temperatures. 相似文献
348.
3‐3′‐Benzylidenebis[4‐hydroxycoumarin] or 4‐nitro,3‐3′‐benzylidenebis[4‐hydroxycoumarin] or 4‐methoxy,3‐3′‐benzylidenebis[4‐hydroxycoumarin] and their complexes with Cu(II), Fe(II) and Fe(III) were synthesized and characterized using 1H‐NMR, 13C‐NMR, IR spectra, electronic spectra, magnetic measurements and elemental analyses. The ligands, metal salts, complexes, control and standard drug were tested for their in‐vitro antibacterial activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella typhi, and Serratia marcescens. The metal complexes exhibit good activity against bacterial strains compared with parental compounds and moderate compared with the standard drug (ciprofloxacin). In‐vitro DNA‐binding activity was carried out using agarose gel electrophoresis. The synthesized compounds show effective DNA‐binding activity. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
349.
1,2,3-Triazole-based sensors for Hg2+ ion have been developed which exhibit NOR and OR logic gate behaviour on using Hg2+ and H+ as inputs. 相似文献
350.
Devery JJ Mohanta PK Casey BM Flowers RA 《Synlett : accounts and rapid communications in synthetic organic chemistry》2009,(9):1490-1494
A convenient approach for the synthesis of tetrasubstituted pyrazoles is described. The method involves the treatment of 1,3-diketones and allyltrimethylsilane with CAN followed by cerium-catalyzed addition of substituted hydrazines to construct pyrazoles in good yields. 相似文献