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91.
Babasaheb P.?BandgarEmail author Vinod T.?Kamble Ankush V.?Biradar 《Monatshefte für Chemie / Chemical Monthly》2005,136(9):1579-1582
Summary. A variety of alcohols were treated with Ph3P and KF in CCl4-DMF at room temperature to afford the corresponding fluorides in very good yields. 相似文献
92.
N.K. Sahoo S. Thakur R.B. Tokas N.M. Kamble 《Applied Physics A: Materials Science & Processing》2007,89(3):711-719
Refractive-index tailoring and morphological evolutions in two different thin film composite systems of gadolinia–silica (Gd2O3:SiO2) and zirconia–silica (ZrO2:SiO2) deposited through reactive electron-beam codeposition processes are discussed in this research paper. For Gd2O3:SiO2 the refractive-index tuning has been achieved from 1.45 to 2.18, whereas in the case of ZrO2:SiO2 the achieved tunable range is from 1.45 to 2.45 in the ultraviolet region. Under certain compositional mixings with lower
silica fractions both the systems demonstrated relative microstructural and morphological densifications. Such evolutions
were very successfully derived through phase-modulated ellipsometry and atomic force microscopy. The composition-dependent
refractive-index tailoring and microstructural densifications have been investigated by adopting Tauc–Lorentz and single-effective-oscillator
models. The morphological correlation functions have also very aptly supported such evolutions in these composite films. These
experimental results indicate their favourable properties and applicability down to the extreme ultraviolet wavelength region
of the electromagnetic spectrum.
PACS 42.79.Wc; 78.66.-w; 78.20.Ci; 61.16.Ch; 42.70.-a;68.55.-a; 68.35.Bs; 81.15.Ef 相似文献
93.
N.K. Sahoo S. Thakur R.B. Tokas A. Biswas N.M. Kamble 《Applied Surface Science》2007,253(7):3455-3463
Composites are pragmatic choices for tailoring the material to have a desired property. Besides, such thin films have scopes to display superior optical, microstructural and morphological properties which are otherwise not possible to obtain from the pure component films. Vapor-phase-mixed binary composite Gd2O3/SiO2 thin film is one such interesting system where band gap as well as refractive index superiority is observed simultaneously under certain compositional mixings. Such and similar observations in composites cannot be explained by Moss empirical rule. Our systematic study on the microstructure of this composite system based on ellipsometry and scanning probe microscopy has satisfactorily provided the information that can explain such optical properties supremacy. Morphological measurements and its derived parameters like autocorrelation and height-height correlation functions have provided several clues that represent the superior grain structures of the composites. Besides, refractive index modeling through effective single oscillator model has strongly supported such analysis results favoring the superior microstructure in composite films. 相似文献
94.
An ultra-low hydrolysis sol-gel route for titanosilicate xerogels and their characterization 总被引:1,自引:0,他引:1
Toney Fernandez Gijo Jose Siby Mathew Rejikumar PR Unnikrishnan NV 《Journal of Sol-Gel Science and Technology》2007,41(2):163-168
In this work TiO2-SiO2 xerogels were prepared through an ultra low hydrolysis method using titanium and silicon alkoxide. The samples were heat
treated to 500°C. The xerogels were characterized using TGA/DTA, FTIR, XRD and TEM. The samples showed the formation of Si–O–Ti
bridges by its characteristic vibration within 925–960 cm−1 range. Si–O–Si bond angles were calculated using the central force network model. The TiO2 in all the samples crystallized on heat treatment to 500°C. The crystallite size calculated using the Scherer formula from
the XRD was verified from the Transmission Electron Micrograph. Samples heat treated to 350°C remained amorphous and hence
could be used as hosts for biomaterials and organic optical materials. 相似文献
95.
Raviraj Kamble Madhulika Singh Nagabhatla Viswanadham 《Reaction Kinetics and Catalysis Letters》2007,92(2):205-211
Three Mo-Pt/H-Mor catalysts, HM-2, HM-3 and HM-4 were prepared by loading 0.05, 0.10 and 0.15 wt.% of Mo, respectively, on
the Pt/H-Mor (HM-1) support. Effect of the Mo loading on the n-hexane hydroisomerization reaction was studied by comparing the products obtained on the parent Pt/H-Mor support and the
three Mo-loaded catalysts. The n-hexane conversions were increased with a Mo loading up to 0.10 wt.% Mo (HM-2), and a further increase of the Mo content to
0.15 wt.% (HM-3) caused a decrease in the conversion. Among the catalysts, HM-3 prepared by 0.10 wt.% Mo loading on Pt-HM
provided the highest isomer yield of 57.4 wt.%, with the highest di-branched isomer selectivity of 11.7 wt.%. The catalytic
activity of Mo-loaded catalysts was greatly influenced by the reaction temperature, i.e., the catalysts exhibited an increase in the isomer yields with increasing reaction temperatures, i.e. from 250°C to 310°C. 相似文献
96.
[Co(P1)], which was designed on the basis of potential hydrogen-bonding interactions in the metal-nitrene intermediate, is a highly active aziridination catalyst with azides. [Co(P1)] can effectively aziridinate various aromatic olefins with arylsulfonyl azides under mild conditions, forming sulfonylated aziridines in excellent yields. The Co-based system enjoys several attributes associated with the relatively low cost of cobalt and the wide accessibility of arylsulfonyl azides. Furthermore, it generates stable dinitrogen as the only byproduct. 相似文献
97.
The reaction conditions for the nicotinamide production by Rhodococcus erythropolis MTCC 1526 have been optimized by statistical experimental design. Application of this approach in the bioprocess can result in rallied product yield, reduced development time, and process variability. In this investigation, response surface methodology and central composite design were employed to predict the levels of variables such as reaction pH (6.5, 7, and 7.5), temperature (15, 20, and 25 degrees C), cell concentration (190, 200, and 210 mg/ml), and substrate concentration (18, 20, and 22 mM) on the production of nicotinamide. A total of 22 experiments were carried out in shake flasks, and a three-dimensional response surface was generated to determine the effect of crucial reaction parameters for the maximum conversion of 3-cynopyridine to nicotinamide. Using this methodology, the optimal values for the reaction conditions were reaction pH 6.85, temperature of 24.8 degrees C, cell concentration of 190.98 mg/ml, and substrate concentration of 21.98 mM. This statistical approach led to the increase of conversion of 3-cynopyridine (93%) as compared to the conversion obtained by one-factor-at-a-time approach (84%). 相似文献
98.
Prasad G. Mahajan Nilam C. Dige Sonali B. Suryawanshi Dattatray K. Dalavi Avinash A. Kamble Dhanaji P. Bhopate Abhijit N. Kadam Vijay V. Kondalkar Govind B. Kolekar Shivajirao R. Patil 《Journal of fluorescence》2018,28(1):207-215
The aqueous suspension of fluorescent nanoparticles were prepared by using 9-anthradehdye derivative (AH). The nanoparticles (AHNPs) were characterized using DLS-zeta sizer and SEM techniques. The photo physical properties of nanoparticles and precursor were measured and compared using UV-absorption spectroscopy, fluorescence spectroscopy and fluorescence lifetime studies. The significant overlap between fluorescence spectrum of AHNPs and excitation spectrum of Riboflavin (RF) led us to explore Fluorescence Resonance Energy Transfer (FRET) studies between AHNPs and RF in aqueous medium. The mechanism of FRET from AHNPs to RF discussed on spectral observations, thermodynamic parameters and changes produces in fluorescence lifetime in absence and presence of different concentrations of RF to AHNPs. The limit of detection for RF (0.071 µM) is considerably low compared with reported methods. Thus, we explore AHNPs as novel nano probe for quantitative determination of RF in pharmaceutical samples based on FRET study. In addition with this, AHNPs has excellent antibacterial activity than the bulk material for two different bacteria culture viz. E. coli and Bacillus sps. 相似文献
99.
A simple method to generate an effective electron-ion interaction pseudopotential from the energy wave number characteristic
obtained by first principles calculations has been suggested. This effective potential has been used, in third order perturbation,
to study the effect of three-body forces on the lattice dynamics of noble metals. It is found that three-body forces, in these
metals, do play an important role. The inclusion of such three-body forces appreciably improves the agreement between the
experimental and theoretical phonon dispersion curves. 相似文献
100.
Sumedh Kamble Peter Valtchev Aiken Dao Thophile Pelras Michael J Rogers Paul B. Savage Fariba Dehghani Aaron Schindeler 《Molecules (Basel, Switzerland)》2021,26(6)
Osteomyelitis and orthopedic infections are major clinical problems, limited by a lack of antibiotics specialized for such applications. In this paper, we describe the design and synthesis of a novel bone-binding antibiotic (BBA-1) and its subsequent structural and functional characterization. The synthesis of BBA-1 was the result of a two-step chemical conjugation of cationic selective antimicrobial-90 (CSA-90) and the bisphosphonate alendronate (ALN) via a heterobifunctional linker. This was analytically confirmed by HPLC, FT-IR, MS and NMR spectroscopy. BBA-1 showed rapid binding and high affinity to bone mineral in an in vitro hydroxyapatite binding assay. Kirby—Baur assays confirmed that BBA-1 shows a potent antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus comparable to CSA-90. Differentiation of cultured osteoblasts in media supplemented with BBA-1 led to increased alkaline phosphatase expression, which is consistent with the pro-osteogenic activity of CSA-90. Bisphosphonates, such as ALN, are inhibitors of protein prenylation, however, the amine conjugation of ALN to CSA-90 disrupted this activity in an in vitro protein prenylation assay. Overall, these findings support the antimicrobial, bone-binding, and pro-osteogenic activities of BBA-1. The compound and related agents have the potential to ensure lasting activity against osteomyelitis after systemic delivery. 相似文献