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1.
A series of novel 3-[5-(1H-indol-3-yl-methyl)-2-oxo-[1,3,4]oxadiazol-3-yl]propionitrile(5),3-[4- amino-3-(1H-indol-3-yl-methyl)-5-oxo-4,5-dihydro-[1,2.4]triazol-1-yljpropionitrile(6),3-[5-(1H- indol-3-yl-methyl)-2-thioxo-[1,3,4]oxadiazol-3-yl]propionitrile(7) and 3-[4-amino-3-(1H-indol-3-yl-methyl) -5-thioxo-4,5-dihydro-[1,2,4]triazol-l -yljpropionitrile(8) were synthesized in good yields from the intermediate(1H-indol-3-yl)-acetic acid N’-(2-cyanoethyl)hydrazide(4).The chemical structures of the newly synthesized compounds were elucidated by their IR,~1H NMR and MS.Further,all the compounds were screened for their antimicrobial activity against Gram-positive,Gram-negative bacteria and also tested their ability toward anti-inflammatory activity.  相似文献   
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A high-sensitive fluorescence cell has been developed with an aim to perform laser spectroscopy of exotic nuclei. This fluorescence cell has been tested off-line for stable isotope 133Cs. Also, an investigation of the nuclear root mean square (r.m.s.) charge and neutron radii, and of the binding energies of the cesium long isotopic chain has been carried out in the relativistic mean field (RMF) and relativistic Hartree–Bogoliubov (RHB) formalisms. The RMF/RHB calculations are compared with the experimental data and are found to be in good agreement.  相似文献   
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Journal of Sol-Gel Science and Technology - Carbon nanotubes (CNTs) uniformly decorated with nano-anatase TiO2 particles corresponding to different TiO2–CNT weight ratios (up to 90 %...  相似文献   
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Here, we report the extracellular biosynthesis of silver nanoparticles (AgNPs) and determination of their antibacterial and anticancer properties. We also explore the efficacy of bioAgNPs incorporated in cellulose nanocrystals (CNCs) and alginate (Alg) for the formation of an antibacterial hydrogel film. Streptomyces sp. PBD-311B was used for the biosynthesis of AgNPs. The synthesized bioAgNPs were characterized using UV-Vis spectroscopy, TEM, XRD, and FTIR analysis. Then, the bioAgNPs’ antibacterial and anticancer properties were determined using TEMA and cytotoxicity analysis. To form the antibacterial hydrogel film, bioAgNPs were mixed with a CNC and Alg solution and further characterized using FTIR analysis and a disc diffusion test. The average size of the synthesized bioAgNPs is around 69 ± 2 nm with a spherical shape. XRD analysis confirmed the formation of silver nanocrystals. FTIR analysis showed the presence of protein capping at the bioAgNP surface and could be attributed to the extracellular protein binding to bioAgNPs. The MIC value of bioAgNPs against P. aeruginosa USM-AR2 and MRSA was 6.25 mg/mL and 3.13 mg/mL, respectively. In addition, the bioAgNPs displayed cytotoxicity effects against cancer cells (DBTRG-0.5MG and MCF-7) and showed minimal effects against normal cells (SVG-p12 and MCF-10A), conferring selective toxicity. Interestingly, the bioAgNPs still exhibited inhibition activity when incorporated into CNC/Alg, which implies that the hydrogel film has antibacterial properties. It was also found that bioAgNP-CNC/Alg displayed a minimal or slow release of bioAgNPs owing to the intermolecular interaction and the hydrogel’s properties. Overall, bioAgNP-CNC/Alg is a promising antibacterial hydrogel film that showed inhibition against the pathogenic bacteria P. aeruginosa and MRSA and its application can be further evaluated for the inhibition of cancer cells. It showed benefits for surgical resection of a tumor to avoid post-operative wound infection and tumor recurrence at the surgical site.  相似文献   
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Nickel nanoparticles have been synthesized by chemical reduction method. By the analysis of X-ray diffraction, the resultant particles are characterized and found to be pure crystalline nickel with a face-centered cubic (FCC) structure. The morphology and size of the nanoparticles are studied by scanning electron microscopy (SEM) and micrographs reveal that the nanoparticles are mostly spherical. The compositional analysis has been carried out by using EDAX. The quantum size confinement of the crystallites is evident from the blue-shift of the absorption edge in the UV–vis absorption spectrum.  相似文献   
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An investigation on the distribution of radium activity levels in the entire south eastern coast of Tamil Nadu, India, from Chennai to Kanyakumari was carried out. Insitu preconcentration technique was adopted by passing 1,000?L of seawater through MnO2 impregnated cartridge filters at all the locations. In the coastal waters, 226Ra and 228Ra concentration was observed to be in the range of 1 to 1.81 and 3.1 to 7.5?mBq/L, respectively with an average of 1.52 and 4.53?mBq/L. respectively, while the sediment samples showed 226Ra activity levels from 8.1 to 129.0?Bq/kg and 228Ra varied from 14.7 to 430.01?Bq/kg. The Kd values for 226Ra was observed to be from 5.3E03 to 3.5E05?L/kg and for 228Ra it was in the range of 2.3E03 to 5.9E04. It was observed that the concentration of 228Ra was more than 226Ra in all the locations. The spatial distribution of the activity with respect to location is discussed in the paper. The radioactive database obtained, represents reference values for coastal environment of Tamil Nadu.  相似文献   
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Journal of Solid State Electrochemistry - Solid polymer electrolyte based on iota-carrageenan (i-carrageeenan) with ammonium thiocyanate (NH4SCN) has been prepared by solution casting technique...  相似文献   
9.
An enzyme-linked immunosorbent assay (ELISA) was developed for azadirachtin (aza), a biopesticide from the neem tree (Azadirachta indica A. Juss). The immunogen was synthesized by epoxidation using the furan ring in the aza molecule. Rabbits were immunized with either bovine serum albumin (BSA)-azadirachtin or ovalbumin (OA)-azadirachtin conjugate. Evaluation of the antisera by antibody capture assay showed that the antibody titer of antisera raised against OA-aza was 1:30,000. An indirect competitive ELISA was developed with BSA-azadirachtin as coating antigen and aza-specific antibodies raised against OA-aza immunogen. The immunoassay showed an inhibitory concentration (IC50) value of 75 ppb, with a range of detection from 0.5 to 1,000 ppb for azadirachtin [based on regression analysis, y= 85.87 (-18.89x); r2 = -0.97]. Cross-reactivity of the antibodies with 2 aza- derivatives (22,23-dihydro-23beta-methoxy azadirachtin and 3-tigloylazadirachtol) was 33 and 29%, respectively. The indirect competitive ELISA was validated and evaluated by quantitating aza in spiked agricultural commodities and from neem formulations. Azadirachtin was spiked into 5 different agricultural commodities: tomato, brinjal, coffee, tea, and cotton seed at 500 and 1,000 ppb and recovered at 62-100%. In samples drawn from 6 lots, the aza content in neem-seed kernels ranged from 0.1 to 0.15%; in commercial neem formulations the content ranged from 200 to 2,000 ppm. The method developed may be applied to environmental monitoring of aza and quality assurance studies of aza-based commercial formulations.  相似文献   
10.
Journal of Radioanalytical and Nuclear Chemistry - A spectrophotometric method, circumventing interference from F− ions, during estimation of Zr in U-Zr alloy fuel, has been developed....  相似文献   
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