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1.
Because Nitrosomonas europaea contains ammonia-oxidizing enzyme, nitrite reductase, and nitrous oxide reductase, the conversion of ammonia to dinitrogen
was tried with different reaction conditions. In aerobic reaction conditions, ammonium was converted to nitrite (NO
2
−
), while under oxygen-limiting or oxygen-free conditions, NO
2
−
-N formed from ammonia oxidation by N. europaea was reduced to N2O and dinitrogen with 22% conversion. During denitrification, optimal pH for the production of N2O and dinitrogen was found to be 7.0–8.0. Dinitrogen was not produced in acidic pH<7.0. A low partial oxygen pressure as well
as oxygen-free conditions are favorable for high production of dinitrogen. 相似文献
2.
3.
Lok Kumar Shrestha 《Journal of Dispersion Science and Technology》2013,34(8):1236-1241
We have investigated the phase behavior of diglycerol monomyristate (DGM) in a variety of organic solvents over a wide range of temperatures and compositions. At lower temperature, there exists a surfactant solid, which solubilize different amounts of oils depending on the oil nature. The melting temperature of the solid phase is virtually constant in a wide range of composition. In all the systems, a lamellar liquid crystal (Lα) is formed in surfactant‐rich regions at intermediate temperatures between the solid‐melt and isotropic two‐ or single‐phase regions. In the dilute regions reverse vesicles are formed in the Lα+O regions mainly in the case of linear hydrocarbon type oils. In the aromatic and cyclic aliphatic oils, there are isotropic solutions at 25°C. However, there is dispersion of α‐solid in the case of liner hydrocarbon oils. Two liquid‐phase regions above the Lα phase are observed in the case of tetradecane and hexadecane. In the shorter chain oil systems, such as octane and decane, no two liquid‐phase appear above Lα region. That is the two liquid‐phase region is largely dependent on the chain length of the oils, and becomes wider in longer hydrocarbon oil. 相似文献
4.
An efficient and facile green synthesis of spirooxindole derivatives bearing pyrano[2,3-c]pyrazole moiety has been achieved via a \(\mathrm{CeO}_{2}\)-NPs catalyzed four-component reaction in water. The protocol offers an environmentally benign and effective approach to highly functionalized and biologically interesting spiro[indoline-3,4\(^\prime \)-pyrano[2,3-c]pyrazole] derivatives. The synthesized compounds exhibit potent antioxidant and antibacterial activities. 相似文献
5.
Back Cover: Yoctoliter Thermometry for Single‐Molecule Investigations: A Generic Bead‐on‐a‐Tip Temperature‐Control Module (Angew. Chem. Int. Ed. 13/2014) 下载免费PDF全文
6.
Simulation of winter air pollution dispersion mechanism of Kathmandu valley by water-tank experiment
Shrestha?M.?L.?Email author Kaga?A. Kondo?A. Inoue?Y. Sugisawa?M. Sapkota?B. 《显形杂志》2004,7(4):317-329
The air pollution concentration in Kathmandu valley in the winter season was found to be higher than in the summer season
due to the formation of the inversion layer. This mechanism was simulated in the water-tank experiment by measuring the temperature
and flow field using liquid crystal thermometry and particle image velocimetry. Thermal stratification was made at the beginning
of the experiment and the surface temperature of the valley model was changed with 12 minutes period matching the diurnal
field temperature pattern of the Kathmandu valley. The updraft wind and Bernard convection occurred during daytime and downdraft
wind and inversion layer were realized during nighttime. The temperature, flow field and mass dispersion characteristics obtained
in the water-tank experiment explained clearly the mechanism of air pollution in Kathmandu valley. 相似文献
7.
8.
Carlos Rodríguez-Abreu Margarita Sanchez-Domínguez Bojan Šarac Marija Bešter Rogač Rekha Goswami Shrestha Lok Kumar Shrestha Dharmesh Varade Goutam Ghosh Vinod K. Aswal 《Colloid and polymer science》2010,288(8):923-935
Mixtures of a hydrophobic triblock copolymer (L121, PEO5PPO68PEO5) and a hydrophobic anionic surfactant (AOT, Sodium bis(2-ethylhexyl)sulfosuccinate), each alone forming turbid vesicular
solutions in water, aggregate to produce a thermodynamically stable, transparent and isotropic solution. Mixed AOT/L121 aggregates
could be confirmed by fluorescence, surface tension, differential scanning calorimetry (DSC) and isothermal titration calorimetry
(ITC). In an isotropic region, where mixed aggregates are formed, there is a synergistic interaction between monomers of AOT
and L121 in the mixture. In addition, Small Angle Neutron Scattering (SANS) experiments provided evidence that mixed aggregates
have the shape of either spheres (with a certain polydispersity) or very short ellipsoids (axial ratio below 2), confirming
a transition from giant multilamellar vesicles to small aggregates upon mixing the two hydrophobic amphiphiles. Upon dilution,
the morphology changes to disk-like. From an examination of the results of all the methods the peculiar behavior of the mixed
AOT/L121 system is explained. 相似文献
9.
10.
Santosh K. Shrestha Heiko Timmers Aidan P. Byrne Wayne D. Hutchison Don H. Chaplin Rakesh Dogra 《Hyperfine Interactions》2004,158(1-4):407-411
A radioisotope ion implanter has been developed using a cesium-sputtering, negative ion source, which offers versatility and
sustained operation. Employing the molecular 111In16O− ion, μCi activities of the radioisotope probe 111In/Cd have been implanted into different material hosts. The implanted tracer activity has been shown to be sufficient for
LTNO, NMRON and PAC. A new NMRON resonance for 111InAg was observed at 75.08 MHz. In2O3 powder performed well as the radioisotope carrier in the ion source, with the ratio of radioisotope and parasitic ion current
being typically 4 × 10−4. 相似文献