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121.
Culture conditions for pullulan production by Aureobasidium pullulans were optimized using response surface methodology at shake flask level without pH control. In the present investigation,
a five-level with five-factor central composite rotatable design of experiments was employed to optimize the levels of five
factors significantly affecting the pullulan production, biomass production, and sugar utilization in submerged cultivation.
The selected factors included concentration of sucrose, ammonium sulphate, yeast extract, dipotassium hydrogen phosphate,
and sodium chloride. Using this methodology, the optimal values for concentration of sucrose, ammonium sulphate, yeast extract,
dipotassium hydrogen phosphate, and sodium chloride were 5.31%, 0.11%, 0.07%, 0.05%, and 0.15% (w/v), respectively. This optimized medium has projected a theoretically production of pullulan of 4.44%, biomass yield of 1.03%,
and sugar utilization of 97.12%. The multiple correlation coefficient ‘R’ was 0.9976, 0.9761 and 0.9919 for pullulan production, biomass production, and sugar utilization, respectively. The value
of R being very close to one justifies an excellent correlation between the predicted and the experimental data. 相似文献
122.
Oxidative coupling of benzylamines with indoles to bis‐(indolyl)methanes (BIMs) was achieved using an inexpensive water‐soluble cobalt complex, Co(bpb). The catalyst was found to be quite effective when air was used as the oxidant and water as solvent under mild reaction conditions. Aromatic amines were successfully converted to the corresponding BIMs with yields up to 85 %. We have successfully carried out a 1 gram scale reaction, and few pharmaceutically relevant compounds were also synthesised by this method in good yields. Control experiments have also been carried out to understand the possible reaction mechanism. 相似文献
123.
The bio-thermal convection in a suspension containing gravitactic microorganisms saturated by a fluid is investigated within the framework of linear and nonlinear stability theory. Energy method is used for nonlinear stability analysis. Effect of Péclet number (swimming speed of microorganisms) and bioconvection Rayleigh number (concentration of microorganisms) on the stability of the system is analyzed numerically by using the Galerkin weighted residual method. The subcritical region of instability for faster swimmers is large as compared to slowly swimmers. Bioconvection Rayleigh number destabilizes the onset of bio- thermal convection and this effect is more predominant for high speed of microorganisms. The Péclet number, bioconvection Rayleigh number increase the size of cell. 相似文献
124.
In this work, an experimental setup consisting of a double pass solar air heater duct provided with discrete multi V-shaped and staggered rib as artificial roughness on both sides of the absorber plate has been designed and fabricated. The parameters of interest investigated experimentally cover a wide range of Reynolds number (Re) from 2000 to 20000, relative staggered rib pitch (p’/p) from 0.2 to 0.8, relative staggered rib size (r/e) from 1 to 4, and relative roughness width (W/w) from 5 to 8. Experimental data related to heat transfer, pressure loss, and thermohydraulic performance has been determined. Substantial improvement has been obtained with some penalty of friction losses. 相似文献
125.
126.
Jianlin Xu Yuchan Chen Zhaoming Liu Saini Li Yong Wang Yuhong Ren Hongxin Liu Weimin Zhang 《中国化学》2021,(5):1104-1112
Main observation and conclusion
Lithocarpins E-G,featuring a rare naturally-occurring highly oxygenated tenellone-macrolide skeleton,were isolated from the cul-... 相似文献
127.
128.
D E Moretti H Saini S Abner L B Keil V A DeBari 《Journal of the International Federation of Clinical Chemistry》1990,2(5):232-237
Autoantibodies directed against the intermediate filament proteins (IF) arise in a variety of disease states. The authors have investigated the binding of the IF to solid membrane supports in a dot blot format in an attempt to develop a simple procedure to detect antibodies (ab) to IF. Commercially obtained, purified IF were utilized. These were: vimentin (VIM), cytokeratin 8 (CYK), glial fibrillary acidic protein (GFA), desmin (DES), and the neurofilament triplet proteins (68, 160, and 200 KDa, respectively designated LMW, MMW, and HMW). Murine monoclonal antibody (mAb) probes were used to detect the presence and immunoreactivity of IF. The mAb were visualized with HRP-anti-mouse conjugates using alpha-chloronaphthol/H 2O 2 as substrate. The membranes studied were nitrocellulose (NC), and two of modified nylon. Nitrocellulose provided the most reproducible binding; no advantage was found to ensue from the use of the other membranes with regard either to quantitative binding or improved capping. Among the IF studied, VIM, GFA, LMW, MMW, and HMW bound well to NC; optimal mass/dot was 1 mug. Filtered, non-fat dry milk is a better capping agent than either albumin or fetal calf serum, but interferes with ab binding to GFA. Binding of CYK and DES is weak at neutral pH. Standard densitometric techniques provide the possibility of quantitation. We conclude that dot and slot blot assays may be practical methods to detect ab to IF antigens. 相似文献
129.
Saini RK Chiang IW Peng H Smalley RE Billups WE Hauge RH Margrave JL 《Journal of the American Chemical Society》2003,125(12):3617-3621
Alkyllithium reagents may be used to attach alkyl groups to the sidewalls of fluoro nanotubes. Thermal gravimetric analysis combined with UV-vis-Nir spectroscopy has been used to provide a quantitative measure of the degree of functionalization. SWNTs prepared using the HiPco process exhibit a higher degree of alkylation than SWNTs from the laser-oven method, indicating that the smaller diameter fluoro tubes are alkylated more readily. The spectral signature of the pristine SWNTs can be regenerated when the alkylated SWNTs are heated in Ar at 500 degrees C, demonstrating that dealkylation occurs at this temperature. TGA-MS analysis using a sample of n-butylated h-SWNTs showed that 1-butene and n-butane are formed during thermolysis. 相似文献
130.
V. P. Pathak T. R. Saini R. N. Khanna 《Monatshefte für Chemie / Chemical Monthly》1983,114(11):1269-1270
Photo-Fries rearrangement of 2-Naphthylbenzoate gives 6-benzoyl-2-naphthol and 8-benzoyl-2-naphthol in addition to the expected product, 1-benzoyl-2-naphthol. 相似文献