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101.
JPC – Journal of Planar Chromatography – Modern TLC - Marmelosin is one of the major phytochemical constituents of Aegle marmelos (L.) Corr. (Rutaceae). Till date, there are no methods...  相似文献   
102.
A simple, efficient, and environmentally benign method for the synthesis of 4H-chromene derivatives was developed using well ordered and recoverable amino functionalized silica gel as a base catalyst. The 4H-chromene derivatives were obtained in short time and excellent yield(87%–96%) by three component reaction of aldehydes, malononitrile and cyclic 1,3-diketones in water at 70 8C.  相似文献   
103.
The platinum(II) complexes with N,S-donor ligand have been synthesised and characterised by physiological techniques like elemental, electronic, Fourier transform infrared, hydrogen-1 nuclear magnetic resonance (1H NMR) and liquid chromatography–mass spectrometry spectra. The synthesised complexes have been checked for their DNA binding ability by absorption titration and viscosity measurement, and the results show that the complexes binds to herring sperm DNA (HS DNA) via covalent mode of binding. The DNA cleavage activity of synthesised complexes has been carried out by gel electrophoresis experiment using supercoiled form of pUC19 DNA, showing the unwinding of the negatively charged supercoiled DNA. Brine shrimp (Artemia cysts) lethality bioassay technique has been applied for the determination of toxic property of synthesised complexes in terms of micromolars.  相似文献   
104.
Journal of Radioanalytical and Nuclear Chemistry - In the present study, the dissolution kinetics of UO2 pellets in nitric acid has been investigated. Kinetic rate expressions based on...  相似文献   
105.
106.
Response surface methodology (RSM) was employed for optimization of medium components and cultural parameters in cost effective cane molasses based medium for attaining high yield of succinic acid. The important factors obtained by “one-variable-at-a-time-approach” (cane molasses, corn steep liquor, sodium carbonate, and inoculum density) were further optimized by RSM. The optimum values of the parameters obtained through RSM (cane molasses 12.5%, corn steep liquor 7.5%, and sodium carbonate 25 mM) led to almost double yield of succinic acid (15.2 g/l in 36 h) as against “one-variable-at-a-time-approach” (7.1 g/l in 36 h) in 500-ml anaerobic bottles containing 300-ml cane molasses based medium. Subsequently, in 10-l bioreactor succinic acid production from Escherichia coli was further improved to 26.2 g/l in 30 h under conditions optimized through RSM. This fermentation-derived succinic acid will definitely help in replacing existing environmentally hazardous and cost-intensive chemical methods for the production of succinic acid.  相似文献   
107.
An amperometric biosensor for oganophosphorus (OP) pesticides based on a carbon nanotube (CNT)-modified transducer and an organophosphorus hydrolase (OPH) biocatalyst is described. A bilayer approach with the OPH layer atop of the CNT film was used for preparing the CNT/OPH biosensor. The CNT layer leads to a greatly improved anodic detection of the enzymatically generated p-nitrophenol product, including higher sensitivity and stability. The sensor performance was optimized with respect to the surface modification and operating conditions. Under the optimal conditions the biosensor was used to measure as low as 0.15 μM paraoxon and 0.8 μM methyl parathion with sensitivities of 25 and 6 nA/μM, respectively.  相似文献   
108.
Soni  Shashank  Jain  N. K.  Joshi  P. V. 《Nonlinear dynamics》2019,96(2):1575-1604
Nonlinear Dynamics - Based on a non-classical plate theory, a nonlinear analytical model is proposed to analyze transverse vibration of thin partially cracked and submerged orthotropic plate in the...  相似文献   
109.
Procedure for hydrothermal synthesis of ZSM-8-type zeolite crystals, using TEA—OH as a template, in the system having molar composition 16.2 (Na2O) — Al2O3 — 117 (SiO2) — 4.8 (TEA)2O — 3887 H2O at 170 °C is described. Results of characterization of these crystals by XRD, IR, EDAX, SEM, TGA, and adsorption studies are described and discussed. X-ray diffraction studies establish that the crystals are ZSM-8-type with structure similar to that of ZSM-5-type crystals. Crystals have prismatic bipyramidal morphology with average size 18–25 microns. Degased calcined samples adsorb xylenes in the order p > m > 0. Pore length per unit cell, estimated from n-hexane adsorption studies, is 46 Å.  相似文献   
110.
Results of microtopographical investigations on prism faces of cultured quartz crystals grown by hydrothermal crystallization techniques, undertaken with a view to determine the influence of microcrystals which get attached to the growing host prism face and then get detached, at some stage of growth, from or still remain attached to the host face, with special reference to the role played by them in the growth and development of host prism faces in particular and the quartz crystals in general, are discussed. The study is an extension of, and obviously to be dealt in continuation with, the earlier one (Part-I, see JOSHI , KOTRU ). Polygonal cavities of various shapes and structures observed on the prism faces are described. Mechanism of formation of the polygonal cavities is explained. Also described are pyramidal depressions, striations, growth hillocks, and etch pits within the cavities on the growing host prism faces. Some of the observed structures within the cavities are attributed to the imprints of the surface structures on the faces of detached microcrystals of quartz. Evidence of growth within the cavities is offered and the implications of such a growth are discussed. Evidence of micro-etching in the cavities is suggestive of the possibilities of some of the grown cultured quartz crystals to get etched in the autoclave. Two different suggestions are made for the interpretation of the origin of etch pits within the cavities, and there is support for the view that they are as a result of etching, only at a time when the supply quartz gets exhausted, of some of the grown crystals where the growing chamber is the hottest.  相似文献   
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