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111.
Nonlinear Dynamics - This paper presents distributed adaptive tracking control algorithms under fixed or switching communication graph for a team of agents, each of which is a special class of... 相似文献
112.
A multiscale model was proposed in a companion paper for assessing the impact of bacterial growth attached to soil particles on the intrinsic permeability of soil. In this paper, this model is used to simulate a column experiment. The simulation conditions are described and the results of the simulation runs are presented. Various possible explanations for the observed reduction in permeability in the column experiment are analyzed using the model and it is concluded that the reduction in the metabolic activity of the attached biomass at the bottom of the column is mainly responsible for the reduction in the intrinsic permeability near the top of the column. Based on the set of parameter values used in the simulations, upper and lower bounds on the reduction in metabolic activity are estimated. 相似文献
113.
M. S. Negi Yogesh Prasad Ganesh Prasad G. S. Gusain Manjari Badoni R. C. Ramola 《Indian Journal of Physics》2009,83(8):1209-1214
The natural pollution level due to gamma radiation was measured in about 22 residential houses around the Tehri Dam Project
in Uttarakhand state by using Environmental Radiation Dosimeter. Both urban and rural houses were selected for the measurements.
The recorded gamma dose rate in indoor atmosphere was found to vary from 25.1 μR/h to 67 μR/h with a mean value 38.6 μR/h
whereas in traditional rural houses the obtained values varied from 42.6 μR/h to 83.5 μR/h with mean value 60.3 μR/h. In outdoor
atmosphere, it was found to vary from 25.1 μR/h to 60 μR/h with an average value 35.8 μR/h. It is observed that the dose rates
are higher in rural houses than that in modern houses. Efforts have also been made to observe deviation of dose rate in the
underground (Power House) atmosphere of Tehri Dam Project in vertical and horizontal mode. It was observed that dose rate
remain almost same in horizontal mode, but a significant variation has been found in the vertical mode. In addition, the variation
of dose rate with type of building material, trend and mode of construction of houses and the age of houses are also discussed
in detail. 相似文献
114.
Ganesh Prasad Yogesh Prasad G. S. Gusain Manjari Badoni J. M. S. Rana R. C. Ramola 《Indian Journal of Physics》2009,83(6):887-892
Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in summer and winter to obtain
the seasonal variation and its correlation with radon exhalation rate. The environmental surface gamma dose rate was also
measured in the same area. The radon exhalation rate in the soil sample collected from different geological unit of Budhakedar
area was measured using plastic track detector (LR-115 type II) technique. The variation in the radon concentration in soil-gas
was found to vary from 1098 to 31,776 Bq.m−3 with an average of 7456 Bq.m−3 in summer season and 3501 to 42883 Bq.m−3 with an average of 17148 Bq.m−3 in winter season. In groundwater, it was found to vary from 8 to 3047 Bq.l−1 with an average value 510 Bq.l−1 in summer and 26 to 2311 Bq.l−1 with an average value 433 Bq.L−1 in winter. Surface gamma dose rate in the study area varied from 32.4 to 83.6 μR.h−1 with an overall mean of 58.7 μ-R.h−1 in summer and 34.6 to 79.3 μR.h−1 with an average value 58.2 μR.h−1 in winter. Radon exhalation rate from collected soil samples was found to vary from 0.1 × 10−5 to 5.7 × 10−5 Bq.kg−1.h−1 with an average of 1.5 × 10−5 Bq.kg−1.h−1 in summer season and 1.7 × 10−5 to 9.6 × 10−5 Bq.kg−1.h−1 with an average of 5.5 × 10−5 Bq.kg−1.h−1. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon
exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation
with radon concentration in water in summer season. Inter-correlations among various parameters are discussed in detail.
相似文献
115.
A carbohydrate-based strategy for the total synthesis of verbalactone has been described. (3R,5R)-3,5-dihydroxydecanoic acid was dimerised under Yamaguchi conditions to provide verbalactone in an overall yield of 17% starting from 3-deoxy-1,2:5,6-di-O-isopropylidine-α-d-glucofuranose. 相似文献
116.
We report a new environmentally-benign, convenient, and facile methodology for the synthesis of 2-substituted-1H-imidazo[4,5-b]pyridine. The reaction of 2,3-diaminopyridine with substituted aryl aldehydes in water under thermal conditions without the use of any oxidative reagent has been studied. The reaction has yielded 1H-imidazo[4,5-b]pyridine derivatives by an air oxidative cyclocondensation reaction in one step in an excellent yield. Furthermore, a series of compounds were synthesized and characterized by melting point, EI-MS, NMR, and IR tools. For comparison, the reference samples were prepared by the reported method. Utilization of aqueous medium, easy reaction conditions, isolation, and purification make this manipulation very interesting from an economic and environmental perspective. 相似文献
117.
Ammonium metavanadate: A novel catalyst for synthesis of 2-substituted benzimidazole derivatives 总被引:1,自引:0,他引:1
Ammonium metavanadate (10 tool%) was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-pbenylenediamine with different substituted aryl aldehydes at room temperature in ethanol. The method was proved to be simple, convenient and the product was isolated with good yields (79-91%). 相似文献
118.
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of l-heptanesulfonic acid sodium salt (10 mol%) at room temperature.The reactions were performed in acetonitrile:water (8:2).The method was proved to be eco-friendly,convenient and the products were isolated with good yields (82-90%). 相似文献
119.
For the extended Taylor-Goldstein problem of hydrodynamic stability governing the stability of shear flows of an inviscid,
incompressible but density stratified fluid in sea straits of arbitrary cross-section a new estimate for the growth rate of
an arbitrary unstable normal mode is given for a class of basic flows. Furthermore the Howard’s conjecture, namely, the growth
rate kc
i
→ 0 as the wave number k → ∞ is proved for two classes of basic flows. 相似文献
120.