CO2 Capturing Mechanism in Aqueous Ammonia: NH3-Driven Decomposition−Recombination Pathway

2011 ◽  
Vol 2 (7) ◽  
pp. 689-694 ◽  
Author(s):  
Dong Young Kim ◽  
Han Myoung Lee ◽  
Seung Kyu Min ◽  
Yeonchoo Cho ◽  
In-Chul Hwang ◽  
...  
Keyword(s):  
Aqueous Ammonia ◽  
Co2 Capturing ◽  
Recombination Pathway

scholarly journals Modelling and simulation study of CO2 capturing process in coal fired power plant using various amine solvents

2019 ◽  
pp. 136-152
Author(s):  
Basudeb Munshi ◽  
Swaraj Panda ◽  
Arvind Kumar
Keyword(s):  
Concentration Level ◽  
Aqueous Ammonia ◽  
Simulation Method ◽  
Co2 Removal ◽  
Environment Friendly ◽  
Solvent Flow Rate ◽  
Co2 Capturing ◽  
Co2 Removal Efficiency ◽  
The Comparative Study ◽  
Influential Parameters

In the present world, Scientists are very much concern on to reduce the concentration level of carbon dioxide in environment to save the world. In the present work, the CO2 capturing efficiencies of three different amine solvents were analyzed. The selected solvents were mono-ethanol amine (MEA), solvent containing mixture of methyl diethanol amine (MDEA) and piperazine (PZ) called activated -MDEA and aqueous ammonia (NH3) solution. Rigorous simulation method was considered in the current study. The effects of different key parameters for different solvents on the CO2 removal efficiency were analyzed. Packing height, solvent temperature and absorber height were the significant influential parameters for MEA system whereas for activated-MDEA (a-MDEA), those are the ratio of the solvent to feed quantity and the mixed solvent PZ concentration level. For aqueous NH3 solution, absorber and stripper’s temperature, CO2 loading, concentration of NH3, height of the absorber, lean and rich solvent flow rate, boil up ratio, regeneration energy, temperature of the condenser, and duty of the reboiler were considered. The comparative study showed that MEA process recovered the maximum CO2 from flue gas. But it was suffered by the maximum regeneration duty. a-MDEA with PZ recovered 91% CO2. Overall, technically, a-MDEA was the best choice as solvent. Compared to a-MDEA and MEA, aqueous ammonia was identified as more propitious and environment friendly solvent due to its satisfactory performance and easy availability.

CONJUGATED OESTROGENS. I

1963 ◽  
Vol 43 (3) ◽  
pp. 345-360 ◽  
Author(s):  
Stanley Kushinsky ◽  
Jane (Wu) Tang
Keyword(s):  
Molecular Weight ◽  
Formic Acid ◽  
Ethyl Acetate ◽  
High Molecular Weight ◽  
Secondary Amine ◽  
Aqueous Ammonia ◽  
Organic Solution ◽  
Extraneous Material

ABSTRACT A convenient and mild procedure is described in this paper whereby free and conjugated oestrogens may be extracted from urine. The extracts containing approximately 90 per cent of the oestrogens are devoid of most of the extraneous material and may be reduced in volume to less than 1/15 of that of the urine. The procedure consists of the following steps: (1) a 10 per cent (v/v) solution of a high molecular weight secondary amine (Amberlite LA-2, Rohm and Haas) in ethyl acetate is washed with formic acid and water, (2) the oestrogens in urine (acidified to pH 2 or 3 with H2SO4) are extracted with the LA-2 solution, (3) the oestrogen fraction is back-extracted from the organic solution with dilute aqueous ammonia.

Mild Temperature Copper-Catalyzed Amination of Aryl Halides with Aqueous Ammonia in the Presence of Pyridyldiketone Ligands

2019 ◽  
Author(s):  
Racha Abed Ali Abdine ◽  
Anna Walczak ◽  
Sultan Abu A Aeash ◽  
Gracjan Kurpik ◽  
Artur R. Stefankiewicz ◽  
...  
Keyword(s):  
Catalytic System ◽  
Aqueous Ammonia ◽  
Aryl Halides ◽  
Efficient Coupling ◽  
Ambidentate Ligand ◽  
Mild Temperature

Ambidentate ligand pyridyldiketones were used in combination with copper to catalyze maintain of aryl halides under very mild temperatures. This novel catalytic system allow efficient coupling in one of the smoothest conditions ever reported in literature.

scholarly journals Improving the Anaerobic Digestion of Swine Manure through an Optimized Ammonia Treatment: Process Performance, Digestate and Techno-Economic Aspects

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 787
Author(s):  
Anna Lymperatou ◽  
Niels B. Rasmussen ◽  
Hariklia N. Gavala ◽  
Ioannis V. Skiadas
Keyword(s):  
Anaerobic Digestion ◽  
Large Scale ◽  
Treatment Process ◽  
Aqueous Ammonia ◽  
Swine Manure ◽  
Batch Experiments ◽  
Ammonia Treatment ◽  
Aqueous Ammonia Soaking ◽  
High Ammonia ◽  
Reduction Efficiency

Swine manure mono-digestion results in relatively low methane productivity due to the low degradation rate of its solid fraction (manure fibers), and due to the high ammonia and water content. The aqueous ammonia soaking (AAS) pretreatment of manure fibers has been proposed for overcoming these limitations. In this study, continuous anaerobic digestion (AD) of manure mixed with optimally AAS-treated manure fibers was compared to the AD of manure mixed with untreated manure fibers. Due to lab-scale pumping restrictions, the ratio of AAS-optimally treated manure fibers to manure was only 1/3 on a total solids (TS) basis. However, the biogas productivity and methane yield were improved by 17% and 38%, respectively, also confirming the predictions from a simplified 1st order hydrolysis model based on batch experiments. Furthermore, an improved reduction efficiency of major organic components was observed for the digester processing AAS-treated manure fibers compared to the non-treated one (e.g., 42% increased reduction for cellulose fraction). A preliminary techno-economic analysis of the proposed process showed that mixing raw manure with AAS manure fibers in large-scale digesters could result in a 72% increase of revenue compared to the AD of manure mixed with untreated fibers and 135% increase compared to that of solely manure.

scholarly journals Genetic Control of Recombination Partner Preference in Yeast Meiosis: Isolation and Characterization of Mutants Elevated for Meiotic Unequal Sister-Chromatid Recombination

Genetics ◽  
1999 ◽  
Vol 153 (2) ◽  
pp. 621-641 ◽  
Author(s):  
Dawn A Thompson ◽  
Franklin W Stahl
Keyword(s):  
Sister Chromatid ◽  
Meiotic Recombination ◽  
Class Ii ◽  
Class Iii ◽  
Viability Analysis ◽  
Isolation And Characterization ◽  
Recombination Checkpoint ◽  
Recombination Pathway ◽  
Checkpoint Genes ◽  
Sister Chromatid Recombination

AbstractMeiotic exchange occurs preferentially between homologous chromatids, in contrast to mitotic recombination, which occurs primarily between sister chromatids. To identify functions that direct meiotic recombination events to homologues, we screened for mutants exhibiting an increase in meiotic unequal sister-chromatid recombination (SCR). The msc (meiotic sister-chromatid recombination) mutants were quantified in spo13 meiosis with respect to meiotic unequal SCR frequency, disome segregation pattern, sporulation frequency, and spore viability. Analysis of the msc mutants according to these criteria defines three classes. Mutants with a class I phenotype identified new alleles of the meiosis-specific genes RED1 and MEK1, the DNA damage checkpoint genes RAD24 and MEC3, and a previously unknown gene, MSC6. The genes RED1, MEK1, RAD24, RAD17, and MEC1 are required for meiotic prophase arrest induced by a dmc1 mutation, which defines a meiotic recombination checkpoint. Meiotic unequal SCR was also elevated in a rad17 mutant. Our observation that meiotic unequal SCR is elevated in meiotic recombination checkpoint mutants suggests that, in addition to their proposed monitoring function, these checkpoint genes function to direct meiotic recombination events to homologues. The mutants in class II, including a dmc1 mutant, confer a dominant meiotic lethal phenotype in diploid SPO13 meiosis in our strain background, and they identify alleles of UBR1, INP52, BUD3, PET122, ELA1, and MSC1-MSC3. These results suggest that DMC1 functions to bias the repair of meiosis-specific double-strand breaks to homologues. We hypothesize that the genes identified by the class II mutants function in or are regulators of the DMC1-promoted interhomologue recombination pathway. Class III mutants may be elevated for rates of both SCR and homologue exchange.

scholarly journals The Yeast Recombinational Repair Protein Rad59 Interacts With Rad52 and Stimulates Single-Strand Annealing

Genetics ◽  
2001 ◽  
Vol 159 (2) ◽  
pp. 515-525 ◽  
Author(s):  
Allison P Davis ◽  
Lorraine S Symington
Keyword(s):  
Protein A ◽  
Single Strand ◽  
Physical Interaction ◽  
Dna Double Strand Breaks ◽  
Single Stranded Dna ◽  
Single Strand Annealing ◽  
Strand Annealing ◽  
Recombination Pathway

Abstract The yeast RAD52 gene is essential for homology-dependent repair of DNA double-strand breaks. In vitro, Rad52 binds to single- and double-stranded DNA and promotes annealing of complementary single-stranded DNA. Genetic studies indicate that the Rad52 and Rad59 proteins act in the same recombination pathway either as a complex or through overlapping functions. Here we demonstrate physical interaction between Rad52 and Rad59 using the yeast two-hybrid system and co-immunoprecipitation from yeast extracts. Purified Rad59 efficiently anneals complementary oligonucleotides and is able to overcome the inhibition to annealing imposed by replication protein A (RPA). Although Rad59 has strand-annealing activity by itself in vitro, this activity is insufficient to promote strand annealing in vivo in the absence of Rad52. The rfa1-D288Y allele partially suppresses the in vivo strand-annealing defect of rad52 mutants, but this is independent of RAD59. These results suggest that in vivo Rad59 is unable to compete with RPA for single-stranded DNA and therefore is unable to promote single-strand annealing. Instead, Rad59 appears to augment the activity of Rad52 in strand annealing.

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