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61.
The conversion of CO2 to useful chemicals, especially to atom economical products, is the best approach to utilize an excess of CO2 present in the atmosphere. In this study, a metal‐organic framework (ZIF‐8) is integrated with nanocrystalline zirconosilicate zeolite to develop an integrated porous catalyst for CO2 insertion reactions. The catalyst exhibits excellent activity for the CO2 insertion reaction of epoxide to produce cyclic carbonate in neat condition without the addition of any co‐catalyst. The catalyst is stable and recyclable during the cyclic carbonate synthesis. Further, the catalyst also exhibits very good activity in another CO2 insertion reaction to produce quinazoline‐2,4(1H, 3H)‐dione. 相似文献
62.
Response surface methodology (RSM) was employed for optimization of medium components and cultural parameters in cost effective
cane molasses based medium for attaining high yield of succinic acid. The important factors obtained by “one-variable-at-a-time-approach”
(cane molasses, corn steep liquor, sodium carbonate, and inoculum density) were further optimized by RSM. The optimum values
of the parameters obtained through RSM (cane molasses 12.5%, corn steep liquor 7.5%, and sodium carbonate 25 mM) led to almost
double yield of succinic acid (15.2 g/l in 36 h) as against “one-variable-at-a-time-approach” (7.1 g/l in 36 h) in 500-ml
anaerobic bottles containing 300-ml cane molasses based medium. Subsequently, in 10-l bioreactor succinic acid production
from Escherichia coli was further improved to 26.2 g/l in 30 h under conditions optimized through RSM. This fermentation-derived succinic acid
will definitely help in replacing existing environmentally hazardous and cost-intensive chemical methods for the production
of succinic acid. 相似文献
63.
64.
Swapnil R. Sarda Jagpal D. Kale Sunil K. Wasmatkar Vijay S. Kadam Pravin G. Ingole Wamanrao N. Jadhav Rajendra P. Pawar 《Molecular diversity》2009,13(4):545-549
Chalcones on condensation with malononitrile and ammonium acetate in the presence of ionic liquid ethylammonium nitrate affords
the corresponding 2-amino-4, 6-diphenylpyridine-3-carbonitrile in excellent yield. The ionic liquid is recycled and reused
several times. 相似文献
65.
66.
Patel Sunil V. Patel Palak R. Patel Samir G. Kanaki Niranjan S. Patel Rajendra K. Patel Archita J. 《平面色谱法杂志一现代薄层色谱法》2016,29(5):380-387
JPC – Journal of Planar Chromatography – Modern TLC - This work represents the validation of a stability-indicating thin-layer chromatographic technique for the simultaneous estimation... 相似文献
67.
The paper presents results of flow visualization and mass transfer studies for fully developed turbulent flow of air in a
square section wind tunnel with repeated chamfered rib roughness on the bottom of the tunnel (rib head chamfer angles ϕ of
-15°, 0°, and 15°; relative roughness pitchp/e = 3, 5, 7.5, and 10). Direct video recordings of flow patterns were made using a simple technique of particles visualization.
For the positively chamfered closely spaced ribs (p/e <- 5) vigorous vortex shedding has been seen compared to the square or negatively chamfered ribs, which is found to be a
function of the Reynolds number. For the widely spaced ribs, the study shows flow separation at the ribs and reattachment
in the inter-rib region. Local mass transfer studies, based on the variation in colour of cobaltous chloride solution impregnated
paper due to evaporation of water, showed a significant improvement in mass transfer rate in the recirculating region in the
wake of ribs with the change in the chamfer angle from -15° to 15°. The positively chamfered 15° ribs are found to be better
than square section ribs atp/e <- 7.5. The performance of negatively chamfered ribs is found to be poor compared to other ribs irrespective of the relative
roughness pitch. 相似文献
68.
D. N. Pant 《General Relativity and Gravitation》1972,3(1-2):29-33
The possibility of the existence of localized charged distribution giving rise to a special axially symmetric electrostatic field has been explored in Einstein's unified field theory [2]. The field equations have been studied in two particular cases. In one case the field equations have a solution representing flat space-time along with an electrostatic field which is constant in the direction of the axis of symmetry. For the other case the solution is non-existent. 相似文献
69.
70.
Rajinder K. Tuli Kailash Chandra Rajendra K. Sharma Narendra Kumar Bhagwan S. Garg 《Transition Metal Chemistry》1980,5(1):49-51
Summary Pseudohalide complexes of the (-cpL)TiXZ type (where cp = cyclopentadienyl, L = -McCs5-H4 and X = N3, NCS, NCO or NCSe) have been prepared in aqueous and nonaqueous media and characterized by elemental analyses, i.r. and n.m.r. spectroscopy. I.r. spectroscopy shows that NCS, NCO and NCSe are bonded to the titanium atom through nitrogen in these complexes which are thus true isothiocyanato, isocyanato and isoselenocyanato derivatives respectively. 相似文献