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61.
Asha V. Chate Ankita S. Kulkarni Chetan K. Jadhav Amol S. Nipte Girabala M. Bondle 《Journal of heterocyclic chemistry》2020,57(5):2184-2193
In this article, we have developed a straightforward, easy and exceedingly competent approach for the synthesis of 5-phenyl-5,6-dihydropyrido[2,3-d]pyrimidine-2,4,7(1H,3H,8H)-triones obtain in superior yields in a sole reaction pace with an air and humidity steady catalyst in water as a green solvent at 100°C. The present procedure paves the approach for the synthesis of biologically fascinating molecular frameworks and has reward in conditions of little catalyst loading with palpable ambiguous and straightforward-to-do reaction circumstances with easy purification process. The used β-cyclodextrin catalyst was recuperated and repeated several times devoid of noteworthy loss of catalytic activity, which is a crucial parameter of green synthesis. 相似文献
62.
A headspace solid-phase microextraction method has been developed for the determination of 8 pesticides in vegetables and fruits by using gas chromatography with an electron capture detector. Two types of fibers (polyacrylate, 85 microm and polydimethylsiloxane, 100 microm) have been assayed and compared. The main factors: extraction and desorption parameters, ionic strength, and the effects of dilution and organic solvents, were studied and optimized. The optimized procedures resulted in more than 80% recovery for all the investigated vegetable and fruit samples with RSD values below 10%. 相似文献
63.
Asha Chaubey Krishan K. Pande Manoj K. Pandey Vijai S. Singh 《Applied biochemistry and biotechnology》2001,96(1-3):239-248
The bienzyme electrodes were fabricated by coimmobilization of lactate oxidase (LOD) and lactate dehydrogenase (LDH) onto
electrochemically prepared polyaniline (PANI) films. These PANI/LOD/LDH bienzyme electrodes were shown to provide signal amplification
by substrate recycling, making it possible to detect l-lactate at lower concentrations (0.1-1 mM). The PANI/LOD/LDH bienzyme electrodes were found to be stable for about 21 d at
4–10°C. 相似文献
64.
Drug metabolism studies are essential and necessary during the evaluation of drugs. This review discusses the in vitro human
liver models to estimate the drug metabolic fates in vivo. Different approaches are provided and emphasis is placed on the
potential of human liver microsomes for drug metabolism and inhibition studies. The methodology for these studies using human
liver microsomes, applications of human liver microsomes, and the drugs studied by human liver microsomes are listed. Human
liver microsomes represent a critical experimental model for the evaluation of drug metabolites with a high probability of
clinical success. 相似文献
65.
GaAs solar cells hold the record for the highest single band-gap cell efficiency. Successful application of these cells in
advanced space-borne systems demand characterization of cell properties like dark current under different ambient conditions
and the stability of the cells against particle irradiation in space. In this paper, the results of the studies carried out
on the effect of 8 MeV electron irradiation on the electrical properties of GaAs solar cells are presented. The I–V (current-voltage) characteristics of the cells under dark and AM1.5 illumination condition are studied and 8 MeV electron
irradiation was carried out on the cells where they were exposed to graded doses of electrons from 1 to 100 kGy. The devices
were also characterized using capacitance measurements at various frequencies before and after irradiation. The effect of
electron irradiation on the solar cell parameters was studied. It is found that only small changes were observed in the GaAs
solar cell parameters up to an electron dose of 100 kGy, exhibiting good tolerance for electrons of 8 MeV energy. 相似文献
66.
Acid phosphatase is ubiquitous in distribution in various organisms. Although it catalyzes simple hydrolytic reactions, it is considered as an interesting enzyme in biological systems due to its involvement in different physiological activities. However, earlier reviews on acid phosphatase reveal some fragmentary information and do not give a holistic view on this enzyme. So, the present review summarizes studies on biochemical properties, structure, catalytic mechanism, and applications of acid phosphatase. Recent advancement of acid phosphatase in agricultural and clinical fields is emphasized where it is presented as potent agent for sustainable agricultural practices and diagnostic marker in bone metabolic disorders. Also, its significance in prostate cancer therapies as a therapeutic target has been discussed. At the end, current studies and prospects of immobilized acid phosphatase are included. 相似文献
67.
V. D. Deepak J. Rajan S. K. Asha 《Journal of polymer science. Part A, Polymer chemistry》2006,44(15):4384-4395
A new class of telechelic urethane methacrylic crosslinkers, based on a cycloaliphatic system (tricyclodecane dimethanol and tricyclodecane monomethanol), was synthesized. The synthesis was achieved by a two‐step condensation of 1,6‐hexamethylene diisocyanate or isophorone diisocyanate with tricyclodecane dimethanol and capping with hydroxyethyl methacrylate. Samples of hexanediol diacrylate, tricyclodecane monomethacrylate, and tricyclodecane dimethacrylate were used as non‐hydrogen‐bonding monomers for comparative studies of the curing kinetics. The photopolymerization of these telechelic systems was investigated with UV irradiation in the presence of 2,2‐diethoxy acetophenone as the photoinitiator, and the kinetics were followed by the monitoring of the double‐bond conversion at 815 cm?1 with Fourier transform infrared spectroscopy. The hydrogen‐bonded crosslinkers had higher double‐bond conversions than their non‐hydrogen‐bonded counterparts under identical conditions. The higher cure rate could be explained by hydrogen‐bonding preassociation in these systems, which brought the methacrylate double bonds within close proximity. The temperature effects on the hydrogen bonding were also investigated. A decrease in the extent of the double‐bond conversion with increasing temperature was observed for the hydrogen‐bonded crosslinker, in contrast to an increased conversion with temperature for hexanediol diacrylate and tricyclodecane dimethacrylate. This was directly indicative of a reduction of hydrogen bonding at elevated temperatures leading to lower conversions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4384–4395, 2006 相似文献
68.
Prospects of conducting polymers in biosensors 总被引:1,自引:0,他引:1
Applications of conducting polymers to biosensors have recently aroused much interest. This is because these molecular electronic materials offer control of different parameters such as polymer layer thickness, electrical properties and bio-reagent loading, etc. Moreover, conducting polymer based biosensors are likely to cater to the pressing requirements such as biocompatibility, possibility of in vivo sensing, continuous monitoring of drugs or metabolites, multi-parametric assays, miniaturization and high information density. This paper deals with the emerging trends in conducting polymer based biosensors during the last about 5 years. 相似文献
69.
Structural Chemistry - The current study primarily involves the investigation of reducing properties of dithia-substituted bicyclic hydrocarbons. Adiabatic electron affinities (AEA) of the selected... 相似文献
70.
Perylenebisimide and naphthalenebisimide (PBI‐PDP and NBI‐PDP) end functionalized with pentadecyl phenol is designed as ditopic hydrogen bonding acceptors to form supramolecular crosslinked network with poly(4‐vinyl pyridine) (P4VP). The pristine PBI‐PDP has been grown as single crystals from DCM‐MeOH (dichloromethane‐methanol) mixture at room temperature, which revealed a P21 space group. Noticeably, the pentadecyl alkyl chain shields the aromatic perylene core on both sides resulting in the absence of π–π interaction in single‐crystal assembly. The naphthalenebisimide derivative exhibits thermotropic liquid crystalline behavior, while both the molecules exhibits lyotropic liquid crystalline phases in tetrahydrofuran (THF), which were characterized using a combination of differential scanning calorimeter, X‐ray diffraction, and polarized light microscopy. The hydrogen‐bonded complex of both the rylenebisimides with P4VP preserves the mesomorphic properties in THF. The electron transport mobility measured by space charge limited current measurements reveals a two orders of magnitude increase in the charge transport in the P4VP complex compared to that of the pristine molecule. The average electron mobility obtained is μ e,avg: 10?3 cm2/Vs for P4VP‐PBI compared to μ e,avg: 10?5 cm2/Vs for pristine PBI derivative. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 951–959 相似文献