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1.
Eric Berson R. Mane Trupti V. Kurt Svihla C. Hanley Thomas R. 《Applied biochemistry and biotechnology》1998,(1):615-627
Variations to the original aeration system in a continuous roller bottle reactor of novel design have been tested and compared
for optimal oxygen (O) delivery. Reactor operating parameters that affect O transfer are rotation rate, liquid-volume level,
fresh-feed rate, and supplementary-aeration rate. Design modifications to enhance gas-liquid O transfer include the addition
of wall baffles and center baffles. The number and location of each of these baffles are compared for their effect on kLa values in the reaction chamber. The liquid feed into the system has been modified to improve the axial liquid mixing and
O transfer. 相似文献
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Sidhanath V. Bhosale Mohan B. Kalyankar Santosh V. Nalage Dattatry S. Bhosale Swati L. Pandhare Trupti V. Kotbagi 《合成通讯》2013,43(5):762-769
A simple one-pot synthesis has been developed for the synthesis of 2,4,5-trisubstituted imidazoles using an efficient and recyclable MoO3/SiO2 solid acid catalyst by condensation of benzil or benzoin, benzaldehyde, and ammonium acetate in acetonitrile as a solvent. Using this solid catalyst, the reactions could be carried out under mild reaction conditions with very good yield of imidazoles, up to 95%. This catalyst could be recycled very easily, which makes this methodology environmentally benign. 相似文献
3.
Sudrik SG Maddanimath T Chaki NK Chavan SP Chavan SP Sonawane HR Vijayamohanan K 《Organic letters》2003,5(13):2355-2358
In situ-generated silver nanoclusters(Ag(n)) during the reduction of either silver(I) oxide or other salts presumably catalyze the Wolff rearrangement of alpha-diazoketones. Their optical, physical, and catalytic properties depend on the starting silver(I) compound and the reaction conditions. [reaction: see text] 相似文献
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Shubhangi B. Umbarkar Trupti V. Kotbagi Ankush V. Biradar Renu Pasricha Jyoti Chanale Mohan K. Dongare Anne-Sophie Mamede Christine Lancelot Edmond Payen 《Journal of molecular catalysis. A, Chemical》2009,310(1-2):150-158
Acetalization of glycerol with various aldehydes has been carried out using mesoporous MoO3/SiO2 as a solid acid catalyst. A series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%) were prepared by sol–gel technique using ethyl silicate-40 and ammonium heptamolybdate as silica and molybdenum source respectively. The sol–gel derived samples were calcined at 500 °C and characterized using various physicochemical characterization techniques. The XRD of the calcined samples showed the formation of amorphous phase up to 10 mol% MoO3 loading and at higher loading of crystalline α-MoO3 on amorphous silica support. TEM analyses of the materials showed the uniform distribution of MoO3 nanoparticles on amorphous silica support. Raman spectroscopy showed the formation of silicomolybdic acid at low Mo loading and a mixture of α-MoO3 and polymolybdate species at high Mo loadings. Moreover the Raman spectra of intermediate loading samples also suggest the presence of β-MoO3. Acetalization of glycerol with benzaldehyde was carried out using series of MoO3/SiO2 catalysts with varying MoO3 loadings (1–20 mol%). Among the series, MoO3/SiO2 with 20 mol% MoO3 loadings was found to be the most active catalyst in acetalization under mild conditions. Maximum conversion of benzaldehyde (72%) was obtained in 8 h at 100 °C with 60% selectivity for the six-membered acetal using 20% MoO3/SiO2. Interestingly with substituted benzaldehydes under same reaction conditions the conversion of aldehydes decreased with increase in selectivity for six-membered acetals. These results indicate the potential of this catalyst for the acetalization of glycerol for an environmentally benign process. 相似文献
8.
Lijo John Georrge J. John Trupti Kholia 《Applied biochemistry and biotechnology》2012,167(5):1340-1350
Leishmaniasis is a group of diseases with a spectrum of clinical manifestations ranging from cutaneous ulcers to visceral leishmaniasis, which results from the bite of an infected sandfly to human. Attempts to develop an effective vaccine have been shown to be feasible but no vaccine is in active clinical use. This study adopts a Reverse Vaccinology approach to identify common vaccine candidates from both highly pathogenic species Leishmania major and Leishmania infantum. Total proteome of both species were compared to identify common proteins, which are further taken for sub-cellular localization and transmembrane helices prediction. Plasma membrane proteins having only one transmembrane helix were first identified and analyzed which are non-homologous in human and mouse in order to avoid molecular mimicry with other proteins. Selected proteins were analyzed for their binding efficiency to both major histocompatibility complex (MHC) class I and class II alleles. As a result, 19 potential epitopes are screened in this study using different approaches, which can be further verified through in vivo experiments in MHC compatible animal models. This study demonstrates that Reverse Vaccinology approach has potential in discovering various immunogenic antigens from in silico analysis of pathogen??s genome or proteome instead of culturing the whole organism by conventional methods. 相似文献
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S. Wagner M. Klein T. Kathrotia U. Riedel T. Kissel A. Dreizler V. Ebert 《Applied physics. B, Lasers and optics》2012,108(3):585-589
Acetylene (C2H2), as an important precursor for chemiluminescence species, is a key to understand, simulate and model the chemiluminescence and the related reaction paths. Hence we developed a high resolution spectrometer based on direct Tunable Diode Laser Absorption Spectroscopy (TDLAS) allowing the first quantitative, calibration-free and spatially resolved in situ C2H2 measurement in an atmospheric non-premixed counter-flow flame supported on a Tsuji burner. A fiber-coupled distributed feedback diode laser near 1535 nm was used to measure several absolute C2H2 concentration profiles (peak concentrations up to 9700 ppm) in a laminar non-premixed CH4/air flame (T up to 1950 K) supported on a modified Tsuji counter-flow burner with N2 purge slots to minimize end flames. We achieve a fractional optical resolution of up to 5×10?5 OD (1σ) in the flame, resulting in temperature-dependent acetylene detection limits for the P17e line at 6513 cm?1 of up to 2.1 ppm?m. Absolute C2H2 concentration profiles were obtained by translating the burner through the laser beam using a DC motor with 100 μm step widths. Intercomparisons of the experimental C2H2 profiles with simulations using our new hydrocarbon oxidation mechanisms show excellent agreement in position, shape and in the absolute C2H2 values. 相似文献
10.
T. Kathrotia U. Riedel A. Seipel K. Moshammer A. Brockhinke 《Applied physics. B, Lasers and optics》2012,107(3):571-584
Chemiluminescence has been observed since the beginning of spectroscopy, nevertheless, important facts still remain unknown. Especially, reaction pathways leading to chemiluminescent species such as OH?, CH?, $\mathrm{C}_{2}^{*}$ , and $\mathrm{CO}_{2}^{*}$ are still under debate and cannot be modeled with standard codes for flame simulation. In several cases, even the source species of spectral features observed in flames are unknown. In recent years, there has been renewed interest in chemiluminescence, since it has been shown that this radiation can be used to determine flame parameters such as stoichiometry and heat release under some conditions. In this work, we present a reaction mechanism which predicts the OH?, CH? (in A- and B-state), and $\mathrm{C}_{2}^{*}$ emission strength in lean to fuel-rich stoichiometries. Measurements have been performed in a set of low-pressure flames which have already been well characterized by other methods. The flame front is resolved in these measurements, which allows a comparison of shape and position of the observed chemiluminescence with the respective simulated concentrations. To study the effects of varying fuels, methane flame diluted in hydrogen are measured as well. The 14 investigated premixed methane–oxygen–argon and methane–hydrogen–oxygen–argon flames span a wide parameter field of fuel stoichiometry (?=0.5 to 1.6) and hydrogen content (H2 vol%=0 to 50). The relative comparison of measured and simulated excited species concentrations shows good agreement. The detailed and reliable modeling for several chemiluminescent species permits correlating heat release with all of these emissions under a large set of flame conditions. It appears from the present study that the normally used product of formaldehyde and OH concentration may be less well suited for such a prediction in the flames under investigation. 相似文献