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501.
502.
Biomass waste, which is abundantly available has been studied as low cost biosorbent for dye sequestration from waste water. The present review reports on recent development for remediation of methylene blue dye by agricultural waste and fruit peel waste material. The aim of this study was to revise latest literature in the field of dye adsorption and discuss the dye adsorption capacity of different types of adsorbents. The activated carbon prepared from several types of biomass waste material enhances the adsorption efficiency after modification. The variety of activating agents, method of activation, characterization of biosorbent material like SEM, EDAX, BET surface area and FTIR analysis has been explored in the present review. The dye adsorption factors such as effect of pH, agitation time, temperature, adsorbate and adsorbent dose were discussed. The detailed investigation on applicability of isotherm model, kinetic model and thermodynamic parameters has also been presented. The adsorption kinetics and adsorption isotherm model focus on selectivity of adsorbent. Adsorption mechanism, Influence of surface area, influence of pHpzc and comparative study of biomass waste adsorbent with other adsorbents have been carried out. The use of biomass waste adsorbents is economically feasible, environmental healthy and found to have outstanding removal capacity of dyes. 相似文献
503.
Yadav Vijay Kumar Das Tanurup Harshey Abhimanyu Yadav Murali Manohar Nigam Kriti Srivastava Ankit 《Chromatographia》2021,84(5):413-423
Chromatographia - Investigation of an arson case presents several challenges to the forensic investigator. Identification of the ignitable liquid residues in the fire debris is one of the crucial... 相似文献
504.
Dennis Liotta Manohar Saindane Robert Monahan Iii David Brothers Adam Fivush 《合成通讯》2013,43(12):1461-1468
1,3-rearrangements of phenylselenenylketones which lack steric bulk at the α-carbon can be conveniently achieved by taking advantage of the greater reactivity of sodium enolates relative to their lithium counterparts. 相似文献
505.
Gourhari Maiti Rajiv KarmakarRudraksha N. Bhattacharya Utpal Kayal 《Tetrahedron letters》2011,52(43):5610-5612
Substituted phenylacetylenes react with various o-hydroxy aromatic aldehydes under dual catalysis of piperidine and FeCl3 in refluxing toluene to yield flavones in good to excellent yield. Atmospheric oxygen acts as stoichiometric oxidant in the process. Some of these compounds had been recently reported to show fair insecticidal activity against Spodoptera frugiperda. 相似文献
506.
The generation of periodic quasicrystals by the projection method is considered. The effects of the simulteneous distortion of the projected icosahedron and 6D hyperlattice are presented. 相似文献
507.
Rajiv T. Sawant Joanne Stevenson Luke R. Odell Per I. Arvidsson 《Tetrahedron: Asymmetry》2013,24(2-3):134-141
Herein we report a facile organocatalytic asymmetric direct cross-aldol reaction of 2-chloroethoxy acetaldehyde with aromatic aldehydes using (S)-(?)-α,α-diphenyl-2-pyrrolidinemethanol as an organocatalyst to afford anti-2-(2-chloroethoxy)-1-arylpropane-1,3-diols with excellent enantioselectivities (95–98%) and moderate diastereoselectivities (3.5–7:1). The 1,3-diols, obtained after the aldehyde reduction, represent highly functional intermediates that allow for further diversification into both chiral 1,4-dioxanes and morpholines, compounds that frequently display interesting biological activities. 相似文献
508.
Rajesh G. Kalkhambkar Geeta M. Kulkarni Manohar V. Kulkarni 《Journal of heterocyclic chemistry》2013,50(5):1014-1020
A high yielding method for the synthesis of new tricyclic coumarins is reported herein using 8‐formyl‐7‐hydroxy‐4‐methyl coumarin as a single synthon. Different strategies were employed to synthesize tricyclic coumarins fused with isoxazole and pyran at C7‐C8 position in the coumarin skeleton. Functional group modifications during the construction of pyrazolyl coumarin has resulted in novel oxidative ipso nitration. The O‐tosylate was subjected to conditions of pressure in a sealed tube experiment, since it was not possible to replace the 7‐hydroxy group of coumarin by regular methods. All the compounds synthesized during the present investigation were characterized by IR, 1H‐NMR, 13C‐NMR, ESI‐MS, and elemental analysis. The X‐ray diffraction data of some of the intermediate hydrazones are also reported herein. 相似文献
509.