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61.
Adams MR Aïd S Anthony PL Baker MD Bartlett J Bhatti AA Braun HM Busza W Carroll T Conrad JM Coutrakon G Davisson R Derado I Dhawan SK Dougherty W Dreyer T Dziunikowska K Eckardt V Ecker U Erdmann M Eskreys A Figiel J Gebauer HJ Geesaman DF Gilman R Green MC Haas J Halliwell C Hanlon J Hantke D Hughes VW Jackson HE Jaffe DE Jancso G Jansen DM Kaufman S Kennedy RD Kirk T Kobrak HG Krzywdzinski S Kunori S Lord JJ Lubatti HJ McLeod D Magill S Malecki P Manz A Melanson H Michael DG Mohr W 《Physical review D: Particles and fields》1994,50(3):1836-1873
62.
A number of new derivatives of 4,6-diaminopyrazolo[3,4-d]pyrimidines substituted in the 1- and/or 3-positions have been obtained from reactions of guanidine carbonate with 1- and/or 3-substituted-5-amino-4-cyanopyrazoles. Use of triethanolamine as a reaction medium permitted preparation of certain derivatives which could not be obtained from the previously described fusion procedure. Some derivatives of 4-aminopyrazolo[3,4-d]pyrimidine with substitution at the 1 - and/or 3-positions were also obtained from reactions of formamide with the same 5-amino-4-cyanopyrazoles. The new compounds were screened for in vivo antimalarial activity, but were found inactive. 相似文献
63.
Summary Reactions between CN– and complexes of MnIII withtrans-1, 2-diaminocyclohexanetetraacetic acid (CyDTA) and hydroxyethylethylenediaminetriacetic acid (HEEDTA) have been studied spectrophotometrically at the maxS of their respective hydroxo species under pseudo-first-order conditions. The forward reaction is found to be first-order with respect to both the metal complex and [CN–].The kinetics of the reverse reaction, i.e. the reaction between [Mn(CN)6]3– and CyDTA4– or HEEDTA3– taken in large excess) have been followed spectrophotometrically. In both systems, the reactions follow first-order kinetics each in [Mn(CN)6]3– and the respective ligand concentration and an inverse first-order dependence in [CN–]. A six step mechanism is proposed for the forward reaction where the fifth step is the rate-determining one. pH, ionic strength and temperature dependences have been studied for both systems. 相似文献
64.
Madhav J. Hebade Rahul D. Kamble Shrikant V. Hese Pratima P. Mogle Ajay N. Ambhore Shuddhodan N. Kadam 《Phosphorus, sulfur, and silicon and the related elements》2016,191(8):1155-1159
An efficient, green, rapid multitasking protocol for the selective C-5 substitution of 2-aminothiazole using iodic acid and aqueous PEG-400 was developed. The method found suitable for C-5 substitution i.e. iodination and thiocyanation of 2-amino thiazole using iodine and ammonium thiocyanate respectively. Iodic acid was found to be a good oxidant and aqueous PEG-400 as green reaction solvent. 相似文献
65.
The present paper reports the preparation of poly (3,4‐ethylenedioxythiophene) (PEDOT) ferrimagnetic conducting polymer composite by incorporation of ferrite particles in the polymer matrix by emulsion polymerization. Synthesis of PEDOT–γ‐Fe2O3 composite was carried out by chemical oxidative polymerization of EDOT with ferrite particles in the presence of dodecylbenzenesulfonic acid (DBSA) that works as dopant as well as surfactant in aqueous medium. The resulting conducting composite possesses saturation magnetization (Ms) value of 20.56 emu/g with a conductivity of 0.4 Scm?1, which was determined by VSM and four probe technique, respectively. B‐H curve reveals that ferrimagnetic particles of γ‐Fe2O3 show super‐paramagnetic behavior at room temperature which was also observed in PEDOT–γ‐Fe2O3 composite. The resulting conducting ferrimagnetic composite shows microwave absorption loss of 18.7–22.8 dB in the frequency range of 12.4–18 GHz. Thermogravimetric analysis of the composite revealed that the composite is thermally stable up to 230°C. The characterization of the PEDOT–γ‐Fe2O3 composite was carried out using XRD and FTIR spectroscopy. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
66.
Ajeet Kaushik Pratima R. Solanki K.N. Sood Sharif Ahmad Bansi D. Malhotra 《Electrochemistry communications》2009,11(10):1919-1923
Fumed silica nanoparticles (NanoSiO2) and chitosan (CH) based nanobiocomposite film have been used to co-immobilize rabbit-immunoglobulin antibodies (r-IgGs) and bovine serum albumin (BSA) for ochratoxin-A (OTA) detection. The observed three-dimensional (3D) arrangement of NanoSiO2 in CH matrix via hydrogen bonding, available NH2/OH groups and excellent film-forming ability of CH results in increased effective surface area of CH–NanoSiO2 nanobiocomposite for r-IgGs immobilization. Electrochemical studies suggest that presence of NanoSiO2 leads to enhanced electrochemical behaviour of CH resulting in increased electron transport between the medium and the electrode. BSA/r-IgGs/CH–NanoSiO2/ITO immunoelectrode exhibits improved sensing characteristics such as linearity (0.5–6 ng/dL), detection limit (0.3 ng/dL), response time (25 s) and sensitivity (18 μA ng/dL cm−2) with correlation coefficient as 0.98. 相似文献
67.
68.
Self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) has been investigated for immobilization of bi-enzymes (ChOx and ChEt) towards development of enzyme biosensors for detection of free and total cholesterol. This enzyme immobilized SAM surface has been characterized by scanning electron microscopy and electrochemical measurements. The results of electrochemical response studies reveal fast enzymatic reaction in phosphate buffer saline solution without using any artificial mediator. This may be attributed to the molecular wire type behavior of short 4-ATP molecule that promotes electron transfer between enzyme and the electrode surface due to its conjugated structure. Interference free estimation of free and total cholesterol has been realized at low operating potential of 0.33 V with range of detection as 25 to 400 mg dl(-1), sensitivity of 542.3 nA mM(-1) (for ChOx/4-ATP/Au) and 886.6 nA mM(-1) (for ChEt-ChOx/4-ATP/Au) with a response time of 20 s at pH 7.4. 相似文献
69.
A hybrid approach has been adopted by using a combination of colloidal graphite (CG) as a conducting filler, 5‐lithium sulfoisophthalic (LiSIPA) acid as a dopant, and polyaniline (PANI) as a matrix to prepare LiSIPA doped PANI–CG composites. The thermal stability (~300°C) and electrical conductivity (67.4 S/cm at 17.4% CG content) have been improved significantly as compared to PANI doped with conventional inorganic dopants like HCl or H2SO4 (130–150°C). The maximum shielding effectiveness value was found to be ?39.7 dB. X‐ray diffraction and infrared spectroscopy showed a systematic shifting of the characteristic peaks and bands with increase in the amount of CG, which indicates significant interaction exists between CG and PANI. The UV–Vis spectra showed the characteristic bands of PANI, with a shift to shorter wavelength with increase in the CG content. The interaction mechanism between doped PANI and CG in the resultant composites has been proposed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
70.
Polyaniline (PANI) and polypyrrole (PPY) were grafted over cotton fabrics by in situ polymerization. FTIR spectra show systematic shifting of bands corroborating surface grafting of conducting polymers on cotton fabric. SEM images revealed that the surface coating of PANI was smoother than PPY. However, better control over coating thickness and uniformity was achieved in PPY fabric. The probable formation mechanism of grated fabrics has also been proposed. The good thermal stability and acceptable electronic conductivity values indicate that these fabrics could be used for electrostatic charge dissipation and microwave absorption. The antistatic studies have shown complete charge dissipation (decay time <0.01 sec). The microwave absorption studies of the conducting fabrics in X‐band (8.2–12.4 GHz) show absorption dominated total shielding effectiveness in the range ?11.3 to ?11.7 dB (>92% attenuation) and ?9.2 to ?9.6 dB (>88% attenuation) for fabrics grafted with PPY and PANI, respectively. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献