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91.
Allan J. Easteal Rakesh Malhotra William E. Price Lawrence A. Woolf 《Journal of solution chemistry》1991,20(3):319-334
Intradiffusion of species in acidified (using eithe hydrochloric or perchloric acid) iron(III) chloride solutions has been
studied using labeled iron(III), chloride and water. Comparison with data for iron(III) perchlorate has enabled the influence
of complexed species upon the diffusion to be ascertained. The chloro-iron species formed have larger diffusion coefficients
than the free iron(III) ion as would be expected from their lower net charge. Simple diffusion models have been employed to
enable estimates of the diffusion of the complexed species and of the free chloride diffusion coefficients to be obtained.
These are discussed in relation to literature data for similar systems. In addition esitmates of the effective hydration of
the iron(III) species in solutions have been obtained from the diffusion data. These are discussed in relation to two other
trivalent metal salt systems, chromium chloride and lanthanum chloride; the overall hydration of the three cations is virtually
identical. 相似文献
92.
Rai B Sathish P Malhotra CP Pradip Ayappa KG 《Langmuir : the ACS journal of surfaces and colloids》2004,20(8):3138-3144
Molecular dynamics simulations incorporating explicit gold atoms in the simulations have been carried out for alkanethiol self-assembled monolayers chemisorbed on the Au(III) surface. The structural properties of the monolayer are evaluated for two force fields: one in which the Au--S--C bond is fixed (FF I), and the other in which it is flexible (FF II). The influence of these force fields on the structural properties of HS(CH2)14CH3 on the structured Au surface is compared at different temperatures. FF I yields greater tilt angles and a smaller film thickness when compared with FF II. Both of the force fields predict that the tilt angles do not follow a monotonic decrease with temperature but show minima around 200 K. Simulations carried out at different chain lengths at 300 K reveal that FF II predicts a greater film thickness than FF I; however, the difference is within 1 A. 相似文献
93.
94.
Anamika Gambhir Manju Gerard A. K. Mulchandani B. D. Malhotra 《Applied biochemistry and biotechnology》2001,96(1-3):249-257
Immobilization of urease and glutamate dehydrogenase enzymes in electrochemically prepared polypyrrole-polyvinyl sulfonate
films (PPY-PVS) was carried out using physical adsorption and electrochemical entrapment techniques. Detailed studies on optimum
pH, Fourier transform infrared spectroscopy, cyclic voltammetry, and scanning electron microscopy of the enzymes in the immobilized
state were conducted. The value of the apparent Michaelis-Menten constant was experimentally determined to be 2.5 and 2.7
for physically adsorbed and electrochemically entrapped urease in PPY-PVS films, respectively. 相似文献
95.
B. D. Malhotra Shuji Hayase Keiichi Kaneto 《Applied biochemistry and biotechnology》2014,174(3):867-868
96.
Ajeet Kaushik Pratima R. Solanki Keiichi Kaneto C. G. Kim Sharif Ahmad Bansi D. Malhotra 《Electroanalysis》2010,22(10):1045-1055
A nanostructured iron oxide (NanoFe3O4, particle size ca. 25 nm and roughness ca. 21 nm) film deposited onto a hydrolyzed indium‐tin‐oxide (ITO) coated glass plate has been used to immobilize cholesterol oxidase (ChOx) to fabricate an impedimetric cholesterol sensor. Electrochemical studies reveal that surface charged Fe3O4 nanoparticles provide better conformation for ChOx loading resulting in enhanced electron transfer between ChOx and the electrode. Impedimetric response studies of the ChOx/NanoFe3O4/ITO bioelectrode exhibit improved linearity (2.5–400 mg/dL), low detection limit (0.25 mg/dL), fast response time (25 s), high sensitivity (86 Ω/mg dL?1/cm?2) and a low value of the Michaelis‐Menten constant (Km, 0.8 mg/dL) with a regression coefficient of 0.997. 相似文献
97.
L. Manral P. K. Gupta M. V. S. Suryanarayana K. Ganesan R. C. Malhotra 《Journal of Thermal Analysis and Calorimetry》2009,96(2):531-534
Flash pyrolysis of fentanyl and its analogues has been studied on pyrolysis-gas chromatograph-mass spectrometer (Py-GC-MS)
system. Initial pyrolytic fragmentation of these compounds led to the formation of N-substituted-1,2,5,6-tetrahydropyridine
and N-phenylpropanamide as the primary pyrolytic products. Moreover, depending up on the furnace temperature, these pyrolytic
products can also undergo further fragmentation to give different compounds. We, herein, discuss the probable fragmentation
routes of parent as well as pyrolytic products. This study will be useful while developing technologies for thermal aerosol
generation of fentanyl and related compounds. 相似文献
98.
Octadecanethiol (ODT) self-assembled monolayer (SAM) prepared onto gold-coated glass plate has been modified by using nitrene reaction of 1-fluoro-2-nitro-4-azidobenzene (FNAB) that further covalently binds to cholesterol oxidase (ChOx) via thermal reaction. FNAB acts as a bridge (cross-linker) between SAM and ChOx. The ChOx/FNAB/ODT/Au electrode thus fabricated has been characterized using contact angle (CA) measurements, UV-vis spectroscopy, electrochemical techniques and X-ray photoelectron spectroscopy (XPS) technique, respectively. This ChOx/FNAB/ODT/Au bioelectrode has been utilized for estimation of cholesterol in solution using surface plasmon resonance (SPR) technique. This SPR based cholesterol biosensor has linearity from 50 to 500 mg/dl of cholesterol in solution with lower detection limit of 50 mg/dl and shelf life of about 2 months when stored at 4 °C. 相似文献
99.
Food borne illnesses contribute to the majority of infections caused by pathogenic microorganisms. Detection of these pathogens originating from different sources has led to increased interest of researchers. New bio-molecular techniques for food pathogen detection are being developed to improve the sensor characteristics such as sensitivity, reusability, simplicity and economic viability. Present article deals with the various methods of food pathogen detection with special emphasis on bio-molecular electronics techniques such as biosensors, microarrays, electronic nose, and nano-materials based methods. 相似文献
100.
Manoj K. Patel Pratima R. Solanki Shruti Seth Sunil Gupta Shashi Khare Ashok Kumar B.D. Malhotra 《Electrochemistry communications》2009,11(5):969-973
Electrochemical DNA sensor has been fabricated by immobilizing thiolated single stranded oligonucleotide (ssDNA) probe onto gold (Au) coated glass electrode for meningitis detection using hybridization with complementary DNA (CtrA) in presence of methylene blue (MB). These electrodes (ssDNA/Au and dsDNA/Au) have been characterized using atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), electrochemical impedance spectroscopy (EIS) and cyclic voltammetric (CV) technique. The DNA/Au electrode can detect the complementary DNA in the range of 7–42 ng/μl in 5 min (hybridization) with response time 60 s and electrode is stable for about 4 months when stored at 4 °C. The sensitivity of dsDNA/Au electrode is 115.8 μA/ng with 0.917 regression coefficient (R). 相似文献