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71.
Asha V. Chate Priyanka K. Bhadke Manisha A. Khande Jaiprakash N. Sangshetti Charansingh H. Gill 《中国化学快报》2017,28(7):1577-1582
An efficient and green method has been developed for the synthesis of 2H-indazolo[2,1-b]phthalazinetriones derivatives by employing 15 mol%β-cyclodextrinvia a one-pot multicomponent reaction of aldehyde,dimedone,hydrazine hydrate with succinic anhydride/phthalic anhydride in water at 80 ℃ for first time.The catalyst could be recovered and reused for four consecutive cycles without appreciable loss in catalytic activity and evaluated for in vitro antimicrobial activity against different Gram-positive and Gram-negative bacterial strains.The outcome of the screening study showed that compound 6d,6f and7 n exhibited excellent activity against E.coil.Whereas,compound 6f and 6h exhibited excellent activity against P.aeurginosa,and compound 6c,and 6e displayed again excellent activity against Staphylococcus aureus whereas compound 7o shows excellent activity against S.aureus and B.subtilis when compared with Ampicillin(standard control).The results indicated that maximum compounds are moderately effective against bacterial growth and their effectiveness is highest against standard drugs. 相似文献
72.
Asha Chaubey Manju Gerard V. S. Singh B. D. Malhotra 《Applied biochemistry and biotechnology》2001,96(1-3):303-311
Tetraethylorthosilicate (TEOS)-derived sol-gel films were utilized for the immobilization of lactate dehydrogenase (LDH) by
physical adsorption and sol-gel/LDH/sol-gel sandwich configuration. An attempt was made to ascertain the optimum pH and temperature
for the immobilized LDH. It was shown that TEOS-derived sol-gel films containing physically adsorbed LDH exhibited linearity
from 0.5 to 4 mM, whereas those containing LDH in sandwich configuration showed linearity from 0.5 to 3 mM
l-lactate. These sol-gel films, immobilized with LDH, were found to be stable for about 4 weeks at 4–10°C. 相似文献
73.
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
74.
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
75.
Balendu Shekher Giri Asha A. Juwarkar D. B. Satpute S. N. Mudliar R. A. Pandey 《Applied biochemistry and biotechnology》2012,167(6):1744-1752
Dimethyl sulfide (DMS) is one of the sulfurous pollutants present in the waste gas generated from the pulp and paper industry. DMS has environmental health implications; therefore, it is necessary to treat the waste gas containing DMS prior to discharge into the environment. A bench-scale biofilter was operated in the laboratory as well as in a pulp and paper industry for the treatment of DMS. Both the biofilters were packed with pre-sterilized wood chips and cow dung/compost of the same origin seeded with biomass developed from garden soil enriched with DMS. The biofilters were operated for the generation of process parameters, and the potential microorganisms isolated from both the biofilters have been purified and characterized for degradation of DMS. Further, these cultures were purified on a basal medium using DMS as a sole carbon source for the growth. Further, the purified cultures were characterized through standard fatty acid methyl esters (FAME)-gas chromatography method, and the isolates were found to be mesophilic, aerobic microbes. These microbes were identified as Bacillus sphaericus-GC subgroup F, Paenibacillus polymyxa, B. sphaericus-GC subgroup F, B. sphaericus-GC subgroup F, and Bacillus megaterium-GC subgroup A, respectively. The potential culture for degradation of DMS was identified as B. sphaericus by 16s rRNA molecular analysis. 相似文献
76.
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
77.
Here we report, for the first time, a novel molecular design for three-dimensional honeycomb structures through a self-organization of hydrogen-bonded bulky anchoring group in a methacrylic polymer backbone. The polymerizable monomer design includes a methacrylic double bond linked to various hydrophobic anchoring units such as ethane, n-decane, tricyclodecane (TCD), and adamantane via a hydrogen-bonded cycloaliphatic urethane linkage. The structures of the polymers were confirmed by nuclear magnetic resonance (NMR) and the molecular weights of the polymer were determined by gel permeation chromatography (GPC). The methacrylate polymers having tricyclodecane and adamantane bulky anchoring groups self-organized to produce three-dimensional honeycomb patterns in tetrahydrofuran-water solvent mixture at ambient conditions, whereas its linear analogues (ethane, n-decane) failed to produce any micropattern. The scanning electron microscopy (SEM) analysis of the above-prepared polymer films revealed that the structure of the polymer played a major role in the formation of the honeycomb patterns. The solution Fourier transform infrared (FTIR) measurements confirmed that the bulky tricyclodecane and adamantane polymers have strong hydrogen-bonding interaction compared to that of their linear analogues, which is the driving force for the micropatterns. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) analysis of the bulky polymers revealed that the polymers exist as vesicles or micelles in the solution, which leads to the formation of the honeycomb pattern. The honeycomb pattern formation in the bulky polymer systems suggests that two cooperative factors such as hydrogen-bonding interaction and hydrophobicity of bulky anchoring units are necessary to induce three-dimensional honeycomb structures. To investigate the effect of molecular weights and its distribution on the self-organization process, both benzoyl peroxide (BPO) initiated free radical and atom transfer radical polymerization (ATRP) techniques were employed for the polymerization. Micropores formed irrespective of differences in molecular weight and polydispersity index (PDI); however, the pore size distribution was influenced by both molecular weights and PDI. Low molecular weight samples afforded polydisperse pores with the ATRP samples with more narrow PDI producing pores with large dimensions. The approach has also been investigated for polystyrene-bulky methacrylic copolymer, and the results revealed that uniform honeycomb patterns were produced for copolymers having more than 50 mol % incorporation of bulky units. 相似文献
78.
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
79.
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
80.
P.P. Hankare S.D. Delekar P.A. Chate A.S. Khomane B.D. Sarwade 《Journal of Physics and Chemistry of Solids》2006,67(12):2506-2511
Crystalline CdSe thin film has been deposited using appropriate precursor solution containing cadmium sulfate octahydrate, tartaric acid, potassium hydroxide, ammonia and sodium selenosulfate. The effect of parameters such as bath composition, deposition temperature, pH of the solution, speed of the rotation and the specificity of complexing agent on growth process is studied. The ‘as-deposited’ CdSe thin film was found to be red in color, specularly reflective and well adherent to the glass substrate. The crystalline phase of the deposited sample was hexagonal wurtzite-type. The analysis of optical absorption data shows energy band gap energy (Eg) 2.01 eV. The morphological study and compositional analysis of film sample have been discussed. The electrical resistivity of CdSe thin film was found to the order of 106 Ω cm. 相似文献