Journal articles: 'Ammonia compound'

1

Suchentrunk, Christof, and Nikolaus Korber. "Reduktion von Isochinolin und Indol mit Cäsium in flüssigem Ammoniak / Reduction of Isoquinoline and Indole with Cesium in Liquid Ammonia." Zeitschrift für Naturforschung B 58, no. 10 (October 1, 2003): 990–96. http://dx.doi.org/10.1515/znb-2003-1009.

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Isoquinoline and indole were reduced with solutions of cesium in liquid ammonia and the resulting crystalline compounds isolated as ammonia-rich solvate crystals. The reduction of isoquinoline yields the anion bisisoquinoline-2,2’-diide in the compound Cs2C18H14N2 · (7/2) NH3 as the result of a coupling reaction. Indole is reduced to the 5,8-dihydroindolide anion in the ammoniate CsC8H8N · 3NH3. Both anions display interactions between their aromatic π-systems and the cesium cations.

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2

Black, DS, N. Chaichit, BM Gatehouse, and GI Moss. "Unusual Formation of New Indole-Containing Heterocyclic Ring Systems." Australian Journal of Chemistry 40, no. 12 (1987): 1965. http://dx.doi.org/10.1071/ch9871965.

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The oxazinoindoletrione (3) underwent reaction with aqueous ammonia in methanol or ethanol to yield the polycyclic methyl or ethyl esters (4) and (5) respectively. Reaction of trione (3) with gaseous ammonia in dry ethanol gave the aminobenzodiazepinone (7). This compound lost ammonia on heating in toluene to give compound (11) and in the presence of methanol or ethanol gave the methyl or ethyl esters (9) and (10) respectively. The structures of compounds (4), (7) and (10) were all established by X-ray crystallography.

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Gärtner, Stefanie, Christof Suchentrunk, and Nikolaus Korber. "Coordination preferences of the alkali cations sodium and caesium in the mixed-cationic Zintl ammoniate Cs3.2Na0.8Ge9·5.3NH3." Acta Crystallographica Section C Structural Chemistry 70, no. 11 (October 11, 2014): 1036–39. http://dx.doi.org/10.1107/s2053229614021998.

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The involvement of two different alkali cations in the nonagermanide ammoniate Cs3.2Na0.8Ge9·5.3NH3[tricaesium sodium nonagermanide–ammonia (1/5.3)] provides insights into the coordination behaviour of ammonia towards sodium and caesium cations within one compound and represents the first mixed-cationic solvate structure of nonagermanide tetraanions. The compound crystallizes in the monoclinic space groupP21/mand, with the presence of pseudomerohedral twinning, mixed-cation sites and disordering of the nonagermanide cage anions, features a combination of crystallographic challenges which could all be resolved during the refinement.

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Xin, L., and NF Curtis. "Compounds of (1,4,8,11-Tetraazacyclotetra-Decane)Copper(II) With 6-Carbamoyl and 13-Carbamoyl, -Methylcarbamoyl, -Ethylcarbamoyl and -Hydrazinocarbonyl Substituents." Australian Journal of Chemistry 45, no. 6 (1992): 1087. http://dx.doi.org/10.1071/ch9921087.

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The (dimethyl trans-1,4,8,1l-tetraazacyclotetradecane-6,13-dicarboxylate)copper(II) cation reacts with ammonia, methylamine or hydrazine to give the dicarbamoyl-, di(methylcarbamoyl)- or di(hydrazinocarbonyl)-substituted complex cations, respectively. The 6,6,13,13-tetra(methoxy- carbonyl)-substituted compound reacts with ammonia at O�C to form the tetracarbamoyl- substituted macrocycle compound [which can also be prepared by condensation of bis(ethane-1,2-diamine)copper(II), formaldehyde and malondiamide], and the dicarbamoyl dicarboxylic acid compound at higher temperatures. Reaction of the tetra(ethoxycarbonyl) compound with ammonia yields a variety of products, depending upon conditions. Reaction of the tetra (ethoxycarbonyl) compound with methylamine yields the di(N- methylcarbamoyl) di(carboxy1ato) substituted macrocycle compound. Condensation of bis(ethane-1,2-diamine)copper(II), formaldehyde and N,N1-diethylmalondiamide yields the tetra(ethylcarbamoyl)-substituted macrocyle compound. A similar reaction with N,N1- dimethylmalondiamide yields a compound with a methylene group additional to the tetra(methylcarbamoyl) formulation.

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Yasuda, Tomoko, Miyoko Waki, Yasuyuki Fukumoto, Hiroaki Saito, and Hiroki Yokojima. "Odorous Compound Removal Performance and Water Properties of a Biotrickling Filter Installed in a Piggery." Applied Engineering in Agriculture 37, no. 4 (2021): 563–72. http://dx.doi.org/10.13031/aea.14443.

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Highlights We evaluated the performance of a two-stage biotrickling filter in a pig facility. A short empty bed residence time lowered the secondary filter removal efficiency for many odorous compounds. The removal efficiency of some compounds increased when the pH in the secondary water tank decreased. Low-odor-threshold compounds such as MT, n-BA, n-PA, and p-cresol were indicated as targets for optimization. Abstract . Odor is a major problem in pig production, and it is important to minimize odor emissions. To determine the factors influencing variations in odor removal efficiency, we analyzed the performance of a biotrickling filter installed in growing-finishing pig rooms on a commercial farm. Over 16 months, we conducted measurements of representative odorous compounds, namely sulfur compounds (hydrogen sulfide, methanethiol, dimethyl sulfide, and dimethyl disulfide), volatile fatty acids (propanoic acid, 2-methylpropanoic acid, butanoic acid, 3-methylbutanoic acid, and pentanoic acid), and ammonia. The average removal efficiencies of methanethiol, dimethyl disulfide, volatile fatty acids, and ammonia were 83% to 89%, with 50% for hydrogen sulfide and 18% for dimethyl sulfide. For many, but not all, odorous compounds, removal efficiency declined significantly with decreasing empty bed residence time (EBRT). From an analysis of the correlations of odorous compounds’ removal efficiency with the properties of the trickling water, we hypothesized that water properties such as pH, free ammonia, free nitrous acid, ionic species (Na+, Ca2+) concentrations, temperature, electrical conductivity, and biological oxygen demand, in addition to EBRT, were associated with fluctuations in removal efficiency during full-scale operation. The pH in the secondary water tank was negatively correlated with the removal efficiencies of methanethiol, dimethyl sulfide, butanoic acid, 3-methylbutanoic acid, pentanoic acid, and ammonia. Our identification of key odorous compounds indicates the importance of the secondary filter in odor treatment. Biotrickling filters for air in pig facilities could be further optimized by targeting low-odor-threshold compounds such as methanethiol, butanoic acid, pentanoic acid, and p-cresol, in addition to ammonia. Keywords: Ammonia, Biotrickling filter, Pig facility odor, Sulfur compound, Trickling water, Volatile fatty acid.

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Undalkar, Rushikesh. "Ammonia Removal from Wastewater of Different Sources and Recent Development in Ammonia Stripping." International Journal for Research in Applied Science and Engineering Technology 10, no. 10 (October 31, 2022): 673–77. http://dx.doi.org/10.22214/ijraset.2022.45946.

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Abstract: Industrial wastewater contains organic impurities such as nitrogen compounds and many more. There is a limit to each compound in wastewater before discharging it into the ecosystem. It is maximum 2000-4000 g N/m3. It also depends upon different countries' environmental conservation laws. As nitrogen is harmful for aquatic life in low concentrations as well, it is needed to be treated before discharging and also before reuse in other applications. the removal of ammonia can be accomplished by steam stripping as well as by air stripping i.e. absorption and desorption. the conventional method of removal of ammonia is packed tower which has many issues in operation. Presently there are many advancements in removal of ammonia and research are going on in this paper we will discuss development in ammonia stripping and application with different sources of waste water from different industries.

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Joseph, Stefanie, Christof Suchentrunk, and Nikolaus Korber. "Dissolving Silicides: Syntheses and Crystal Structures of New Ammoniates Containing Si52– and Si94– Polyanions and the Role of Ammonia of Crystallisation." Zeitschrift für Naturforschung B 65, no. 9 (September 1, 2010): 1059–65. http://dx.doi.org/10.1515/znb-2010-0901.

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The dissolution of the ternary material K6Rb6Si17 in liquid ammonia yields the solvate compound Rb4Si9 ・ 5NH3, which contains fourfold negatively charged nine atom silicon clusters Si94−. Using additionally the [2.2.2] cryptand during the dissolution results in the solvate [K(2.2.2- crypt)]2Si5 ・ 4NH3 , in which the Si52− anion is present in the crystal structure. The Si52− anion has the shape of a nearly ideal trigonal bipyramid. The starting material K6Rb6Si17 contains both Si44− and Si94− Zintl anions. In ammoniate crystal structures, Si94− anions are accessible independently of Si44− anions, and ammonia of crystallisation plays a major role in the observed crystal symmetry. For the cryptate structures of Si52− and Ge52− anions ammonia of crystallisation is obligatory despite the loss of crystal symmetry compared to the crystal structures of the heavier homologues Pb52− and Sn52−.

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8

Béres, Kende Attila, István E. Sajó, György Lendvay, László Trif, Vladimir M. Petruševski, Berta Barta-Holló, László Korecz, et al. "Solid-Phase “Self-Hydrolysis” of [Zn(NH3)4MoO4@2H2O] Involving Enclathrated Water—An Easy Route to a Layered Basic Ammonium Zinc Molybdate Coordination Polymer." Molecules 26, no. 13 (June 30, 2021): 4022. http://dx.doi.org/10.3390/molecules26134022.

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An aerial humidity-induced solid-phase hydrolytic transformation of the [Zn(NH3)4]MoO4@2H2O (compound 1@2H2O) with the formation of [(NH4)xH(1−x)Zn(OH)(MoO4)]n (x = 0.92–0.94) coordination polymer (formally NH4Zn(OH)MoO4, compound 2) is described. Based on the isostructural relationship, the powder XRD indicates that the crystal lattice of compound 1@2H2O contains a hydrogen-bonded network of tetraamminezinc (2+) and molybdate (2−) ions, and there are cavities (O4N4(μ-H12) cube) occupied by the two water molecules, which stabilize the crystal structure. Several observations indicate that the water molecules have no fixed positions in the lattice voids; instead, the cavity provides a neighborhood similar to those in clathrates. The @ symbol in the notation is intended to emphasize that the H2O in this compound is enclathrated rather than being water of crystallization. Yet, signs of temperature-dependent dynamic interactions with the wall of the cages can be detected, and 1@2H2O easily releases its water content even on standing and yields compound 2. Surprisingly, hydrolysis products of 1 were observed even in the absence of aerial humidity, which suggests a unique solid-phase quasi-intramolecular hydrolysis. A mechanism involving successive substitution of the ammonia ligands by water molecules and ammonia release is proposed. An ESR study of the Cu-doped compound 2 (2#dotCu) showed that this complex consists of two different Cu2+(Zn2+) environments in the polymeric structure. Thermal decomposition of compounds 1 and 2 results in ZnMoO4 with similar specific surface area and morphology. The ZnMoO4 samples prepared from compounds 1 and 2 and compound 2 in itself are active photocatalysts in the degradation of Congo Red dye. IR, Raman, and UV studies on compounds 1@2H2O and 2 are discussed in detail.

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9

Shi, Jianchao, Lianxiang Wang, Yongrui Yang, and Tinglin Huang. "Effects of Seasonal Thermal Stratification on Ammonia Nitrogen Transformation in a Source Water Reservoir." Processes 9, no. 12 (December 9, 2021): 2218. http://dx.doi.org/10.3390/pr9122218.

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Seasonal thermal stratification has a significant impact on water quality. In this paper, the variation of vertical distribution of ammonia nitrogen in a source water reservoir was studied, on the base of field monitoring data. The dominant factor of the variation in ammonia nitrogen is the anaerobic environment caused by the seasonal thermal stratification, which leads to the degradation of nitrogen-containing organic compounds in the sediments. To determine the rates of ammonia accumulation, an in situ experimental chamber was used. The results showed that, before the formation of thermal stratification in the reservoir, sediments in the bottom of the water have a high tendency to release ammonia; the rates of ammonia accumulation in the overlying water are 40.31–111.41 mg·m−2·d−1. However, thermal stratification causes changes in the physical and chemical properties of the sediment and reduction in the degradability of the nitrogen-containing compound in the sediment. The rates of ammonia accumulation (39.44–44.65 mg·m−2·d−1) after thermal stratification are lower than before. Considering the water pollution hazards caused by seasonal thermal stratification, it is necessary to take corresponding emergency response measures to cope with the possibility of water pollution risk.

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Tran, Thanh Trung, Nathan J. Bott, Rebecca van Gelderen, Nam Trung Nguyen, Phuong Minh Thi Chu, and Ha Hoang Chu. "Comparative Genome Analysis of Two Heterotrophic Nitrifying Pseudomonas putida Strains Isolated from Freshwater Shrimp Ponds in Soc Trang Province." Fermentation 8, no. 7 (July 17, 2022): 336. http://dx.doi.org/10.3390/fermentation8070336.

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Nitrogen compounds, especially ammonia, are widely produced in aquaculture systems during cultivation. Ammonia has been investigated as a model compound for use by heterotrophic nitrifying bacteria. Pseudomonas TT321 and Pseudomonas TT322, isolated from shrimp pond water in Soc Trang province, Vietnam, are identified by comparing them with 31 of the closest genomes sequences from the NCBI nucleotide database. The genome sizes of strains TT321 and TT322 were 5,566,241 bp and 5,563,644 bp, respectively. No plasmids were evident in these strains. Genome analysis revealed that TT321 and TT322 belonged to Pseudomonas putida and shared a common ancestor with 33 genomes. Analysis based on the comparison of genomes showed that three genes, carbamate kinase (arcC), glutamine synthetase (Glul), and aminomethyltransferase (amt), are involved in three metabolic pathways. These pathways are: (i) arginine and proline metabolism, (ii) alanine, aspartate and glutamate metabolism, and (iii) glycine, serine and threonine metabolism. These genes may play important roles in ammonia reduction and support bacterial growth via ammonia assimilation.

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Fattah, Tanzeela A., Aamer Saeed, Zaman Ashraf, Qamar Abbas, Pervaiz A. Channar, Fayaz A. Larik, and Mubashir Hassan. "4-Aminocoumarin based Aroylthioureas as Potential Jack Bean Urease Inhibitors; Synthesis, Enzyme Inhibitory Kinetics and Docking Studies." Medicinal Chemistry 16, no. 2 (February 20, 2020): 229–43. http://dx.doi.org/10.2174/1573406415666190715164834.

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Background: Urease enzyme catalyzes the hydrolysis of urea into ammonia and CO2, excess ammonia causes global warming and crop reduction. Ureases are also responsible for certain human diseases such as stomach cancer, peptic ulceration, pyelonephritis, and kidney stones. New urease inhibitors are developed to get rid of such problems. Objective: This article describes the synthesis of a series of novel 1-aroyl-3-(2-oxo-2H-chromen-4- yl)thiourea derivatives (5a-j) as Jack bean urease inhibitors. Methods: Freshly prepared aryl isothiocyanates were reacted with 4-aminocoumarin in the same pot in an anhydrous medium of acetone. The structures of the title thioureas (5a-j) were ascertained by their spectroscopic data. The inhibitory effects against jack bean urease were determined. Results: It was found that compounds 5i and 5j showed excellent activity with IC50 values 0.0065 and 0.0293, µM respectively. Compound 5i bearing 4-methyl substituted phenyl ring plays a vital role in enzyme inhibitory activity. The kinetic mechanism analyzed by Lineweavere-Burk plots revealed that compound 5i inhibits the enzyme non-competitively. The Michaelis-Menten constant Km and inhibition constants Ki calculated from Lineweavere-Burk plots for compound 5i are 4.155mM and 0.00032µM, respectively. The antioxidant activity results displayed that compound 5j showed excellent radical scavenging activity. The cytotoxic effects determined against brine shrimp assay showed that all of the synthesized compounds are non-toxic to shrimp larvae. Molecular docking studies were performed against target protein (PDBID 4H9M) and it was determined that most of the synthesized compounds exhibited good binding affinity with the target protein. Molecular dynamics simulation (MDS) results revealed that compound 5i forms a stable complex with target protein showing little fluctuation. Conclusion: Based upon our investigations, it is proposed that 5i derivative may serve as a lead structure for devising more potent urease inhibitors.

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Racha, Hanumandlu, Balakishan Vadla, Kavitha Peddolla, and Sailu Betala. "Synthesis and Anticancer Activity of Novel Hetero Ring Fused Pyridine Amide Derivatives." Asian Journal of Chemistry 31, no. 11 (September 28, 2019): 2485–91. http://dx.doi.org/10.14233/ajchem.2019.22150.

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A series of novel hetero ring fused pyridine amide derivatives were prepared starting from ethyl furo[2,3-b]pyridine-2-carboxylate (3) on reaction with ammonia to afford furo[2,3-b]pyridine-2-carboxamide (4), compound 4 on reaction with trifluoroacetic acid to give compound 5, which on reaction with bromoethyl acetate followed by hydrazine hydrate to give compound 7. Compound 7 when reacted with different substituted aromatic aldehydes to give Schiff base compounds (8a-l). Similarly, compound 6a when reacted with diverse substituted aliphatic amines to give amide derivatives (9a-h). All the synthesized compounds 8a-l and 9a-h were screened for anticancer activity against four cancer cell lines such as A549-lung cancer (CCL-185); DU145-prostate cancer (HTB-81); SiHa-squamous cell carcinoma (HTB-35); MCF-7-breast cancer (HTB-22); HEK-29-human embryonic kidney cells (CRL-1573). Compounds 9e and 9f are found to have promising anticancer activity at micro molar concentration and found to be non-toxic on normal cell line.

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Mazure, N., and N. Truffaut. "Degradation of morpholine by Mycobacterium aurum MO1." Canadian Journal of Microbiology 40, no. 9 (September 1, 1994): 761–65. http://dx.doi.org/10.1139/m94-120.

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When Mycobacterium aurum MO1 was grown with morpholine, the release of ammonia into the supernatant was proportional to the disappearance of morpholine, showing that this compound was mineralized. MO1 was able to grow in high concentrations of morpholine but accumulation of ammonia inhibited growth and degradation of morpholine. Immobilization of bacterial cells in carrageenan gel beads showed that morpholine degradation in these conditions began earlier and was faster than in free culture. One of the two branches of the lower pathway of morpholine biodegradation was induced while the other branch was inhibited in the presence of morpholine. Strain MO1 grew on heterocyclic compounds similar to morpholine, demonstrating that MO1 is able to degrade heterocyclic compounds containing nitrogen atoms (piperidine and pyrrolidine). Compounds containing sulphur or oxygen atoms or compounds with double bonds were not degraded.Key words: Mycobacterium aurum, morpholine, biodegradation.

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Liu, Yue, Hong Ni, Gang Li, and Dafeng Zhi. "Research on NH₃-SCR reductant technology progress for diesel vehicles." E3S Web of Conferences 360 (2022): 01030. http://dx.doi.org/10.1051/e3sconf/202236001030.

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This paper describes the technical principle, research status and application status of four reducing agents (aqueous urea solution, solid ammonium salt, solid ammonia compound and liquid ammonia) which supply NH3 for SCR of diesel vehicles, introduces the replacement methods of solid ammonia, and analyzes the application feasibility of liquid ammonia. A comprehensive comparative study of the four reducing agents is carried out in terms of storage and validity requirements, low temperature performance, ammonia storage capacity, replacement mode, replacement frequency, safety, cost and future application prospect. It is found that the ammonia storage density of solid ammonia and liquid ammonia is 2.5 ~ 3.5 times of that of aqueous urea solution. And there is no significant difference in the theoretical use cost of several reducing agents, however, the actual use cost of aqueous urea solution is higher than the theoretical value on account of its actual decomposition rate less than 100%. The analysis shows that the requirements for NH3-SCR reductant technology in the future are excellent low temperature supply capacity, small space occupation, convenient use, low cost and guaranteed quality, and etc. As a traditional technology, aqueous urea solution is easy to crystallize at low temperature and can not meet the requirements of low temperature performance. Solid ammonium salt also has the problem of crystallization at low temperature. Solid ammonia compounds meet the above requirements, and the market application is gradually mature. If liquid ammonia wants to be applied in large-scale engineering, its safety problem of storage tank should be solved.

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Yamaguchi, Haruhiko, and Kyoko Yoshino. "Influence of Tannin-Copper Complexes as Preservatives for Wood on Mechanism of Decomposition by Brown-Rot Fungus Fomitopsis palustris." Holzforschung 55, no. 5 (September 19, 2001): 464–70. http://dx.doi.org/10.1515/hf.2001.077.

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SummaryThe mechanism of preservation by chemically modified tannin and tannin-ammonia-copper agents was examined. Wood decay byF. palustriswas markedly suppressed by processing wood with agents made by mixing chemically modified tannins with ammonia and cupric chloride. When wood powder was treated with these agents, mycelial growth and generated protein increased to some extent. The preservative effects of the chemically modified tannins (RMT and CMT) or compound agents composed of the tannins and ammonia-copper were considered to be due to inhibition of the activities of xylanase, mannase and Cx-cellulase. In the culture medium in which treated wood powder was brought in with these agents, drop of pH by oxalic acid, whichF. palustrisproduces, is not generated. The potency of the effect was thought to be due to chelation of copper, an essential trace element for wood decay byF. palustris, by the tannin, and/or neutralization or suppression of oxalic acid production by ammonia-copper.

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Grassl, Tobias, and Nikolaus Korber. "Tetraammineplatinum(II) dichloride ammonia tetrasolvate." Acta Crystallographica Section E Structure Reports Online 70, no. 7 (June 7, 2014): i31. http://dx.doi.org/10.1107/s1600536814012343.

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The title compound, [Pt(NH3)4]Cl2·4NH3, was crystallized in liquid ammonia from the salt PtCl2. The platinum cation is coordinated by four ammonia molecules, forming a square-planar complex. The chloride anions are surrounded by nine ammonia molecules, either bound within the platinum complex or solvent molecules. The solvent ammonia molecules are packed in such a way that an extended network of N—H...N and N—H...Cl hydrogen bonds is formed. The structure is isotypic with [Pd(NH3)4]Cl2·4NH3[Grassl & Korber (2014).Acta Cryst.E70, i32].

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Grassl, Tobias, and Nikolaus Korber. "Tetraamminepalladium(II) dichloride ammonia tetrasolvate." Acta Crystallographica Section E Structure Reports Online 70, no. 7 (June 7, 2014): i32. http://dx.doi.org/10.1107/s1600536814012355.

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The title compound, [Pd(NH3)4]Cl2·4NH3, was crystallized in liquid ammonia from the salt Pd(en)Cl2(en is ethylenediamine) and is isotypic with [Pt(NH3)4]Cl2·4NH3[Grassl & Korber (2014).Acta Cryst.E70, i31]. The Pd2+cation is coordinated by four ammonia molecules, exhibiting a square-planar geometry. The chloride anions are surrounded by nine ammonia molecules. These are either bound in the palladium complex or solvent molecules. The packing of the ammonia solvent molecules enables the formation of an extended network of N—H...N and N—H...Cl interactions with nearly ideal hydrogen-bonding geometry.

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Aksenchik, Konstantin V. "EVOLUTION AND PROSPECTS OF ENERGY AND RESOURCE SAVING APPROACHES IN AMMONIA TECHNOLOGY." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 64, no. 1 (December 8, 2020): 4–21. http://dx.doi.org/10.6060/ivkkt.20216401.6310.

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Nitrogen is one of the nutrients required for plant nutrition. The problem of fixing atmospheric nitrogen continues to be relevant at the present time. If at the beginning of the 20th century the problem was solved in the direction of ammonia synthesis, today the search trend has shifted to energy and resource saving. The presence of a strong triple chemical bond in the nitrogen molecule determines the high energy intensity of industrial production of bound nitrogen compounds. This review article is examined the evolution of ammonia technology, as the most common compound of fixed nitrogen, from the standpoint of improving approaches to energy and resource saving. The existing high rates of consumption of fossil carbon fuels, especially natural gas, which is currently the main raw material for the production of ammonia, and the associated annual growing emissions of carbon dioxide into the atmosphere, require scientists around the world to research for alternative methods of industrial production of ammonia. In this article, an attempt is made to identify the features and chronological framework of the main stages in the development of approaches to energy and resource saving in ammonia technology. The methods of improvement and contributing factors in relation to the stages of development are determined. A comparative assessment of the known options for the technology of ammonia and bound nitrogen compounds in terms of resource and energy consumption at different stages of development is given. Comparison of the power technology units for ammonia synthesis operating in Russia in terms of resource and energy consumption is performed. It is shown that the current state of ammonia technology is characterized by an almost complete exhaustion of possible options for further energy and resource saving of known technological schemes. It is shown that ammonia technologies using natural gas in the future will no longer meet the tightening requirements for the level of carbon dioxide emissions. The estimation of energy consumption of alternative methods of ammonia production is given.

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Aksenchik, Konstantin V. "EVOLUTION AND PROSPECTS OF ENERGY AND RESOURCE SAVING APPROACHES IN AMMONIA TECHNOLOGY." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 64, no. 1 (December 8, 2020): 4–21. http://dx.doi.org/10.6060/ivkkt.20216401.6310.

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Nitrogen is one of the nutrients required for plant nutrition. The problem of fixing atmospheric nitrogen continues to be relevant at the present time. If at the beginning of the 20th century the problem was solved in the direction of ammonia synthesis, today the search trend has shifted to energy and resource saving. The presence of a strong triple chemical bond in the nitrogen molecule determines the high energy intensity of industrial production of bound nitrogen compounds. This review article is examined the evolution of ammonia technology, as the most common compound of fixed nitrogen, from the standpoint of improving approaches to energy and resource saving. The existing high rates of consumption of fossil carbon fuels, especially natural gas, which is currently the main raw material for the production of ammonia, and the associated annual growing emissions of carbon dioxide into the atmosphere, require scientists around the world to research for alternative methods of industrial production of ammonia. In this article, an attempt is made to identify the features and chronological framework of the main stages in the development of approaches to energy and resource saving in ammonia technology. The methods of improvement and contributing factors in relation to the stages of development are determined. A comparative assessment of the known options for the technology of ammonia and bound nitrogen compounds in terms of resource and energy consumption at different stages of development is given. Comparison of the power technology units for ammonia synthesis operating in Russia in terms of resource and energy consumption is performed. It is shown that the current state of ammonia technology is characterized by an almost complete exhaustion of possible options for further energy and resource saving of known technological schemes. It is shown that ammonia technologies using natural gas in the future will no longer meet the tightening requirements for the level of carbon dioxide emissions. The estimation of energy consumption of alternative methods of ammonia production is given.

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Soujoudi, Ray, and Randall Manteufel. "Thermodynamic, Economic and Environmental Analyses of Ammonia-Based Mixed Refrigerant for Liquefied Natural Gas Pre-Cooling Cycle." Processes 9, no. 8 (July 27, 2021): 1298. http://dx.doi.org/10.3390/pr9081298.

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Analyzing the entire liquefaction cycle, using a large temperature span with many degrees of freedom, may not always result in a practical solution. The objective of this paper is to investigate the feasibility of using an environmentally friendly refrigerant compound, ammonia, in the mixed refrigerant (MR) for the liquefied natural gas (LNG) pre-cooling cycle through thermodynamic performance, economic analyses and environmental impact. Fifteen cases studies within three major mixed refrigerants groups of MR-1, MR-2 and MR-3 were developed by adding ammonia to various molar compositions of lighter and heavier hydrocarbons. The thermodynamic analysis shows increasing ammonia’s concentrations in the mixed refrigerant by 10% had the largest enhancement on coefficient of performance (COP) of MR-1 by 0.67 and decreased the specific energy consumption of the pre-cooling cycle by 128 kJ/kg compared to the base case. Economic analyses revealed that the mixed refrigerant MR-1, with ammonia, methane, ethane and propane, benefited the most from higher concentration of ammonia in the mixed refrigerant, which resulted in both lower annual capital and operational costs by $2.52 MM and $3.67 MM, respectively. Lastly, reducing the methane concentration in MR and replacing it with ammonia, decreased the amount of refrigerant leakage through compressor’s seals and reduced the global warming potential index (GWPI) of mixed refrigerant up to 24.3%.

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Gao, Long Long, Yan Zhen Yu, Miao Wan Li, Yu Xing Zhou, and Hua Dong Zhang. "Adsorption Performance of Ammonia onto Compound Clinoptilolite Filter Material." Applied Mechanics and Materials 295-298 (February 2013): 443–46. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.443.

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In order to combine the microbial metabolism characteristics in biological aerated filter (BAF) with the adsorption and ion-exchange ability of natural clinoptilolite to treat sanitary wastewater, the experiment use clinoptilolite powder as main materials to prepare the large specific surface and high porosity spherical compound filter material by adding adhesive and pore-forming agent etc and get better effect on sanitary wastewater treatment.The static adsorption test showed that the adsorb ratios of ammonia-nitrogen is 58.5% when the compound filter material dosage was 100g/L, NH3-N concentration was 100mg/L and the contact time was 40min.The cure fitting of the adsorption isotherm of NH3-N on the compound filter material could be well described by the Langmuir formula and the coefficient of determination is 0.99216.

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Kondratev, V. M., A. Kuznetsov, S. V. Fedina, S. S. Nalimova, V. A. Moshnikov, and A. D. Bolshakov. "Gallium phosphide nanowires for “biological concentrations” ammonia detection." Journal of Physics: Conference Series 2172, no. 1 (February 1, 2022): 012006. http://dx.doi.org/10.1088/1742-6596/2172/1/012006.

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Abstract Ammonia is widespread chemical compound found both in nature and in human body, and its detection is very important in biology and medicine as well as in environmental monitoring systems. This work is aimed at fabrication and study of precise, technological and relatively cheap ammonia sensors compatible with a liquid medium. Here we use GaP epitaxial nanowires (NWs) as adsorption elements capable of ammonia detection fabricated via a simple protocol. The device properties are studied in terms of change in sensor impedance spectrum upon presence of ammonia. Physical interpretation of the impedance spectra in the presence of water and ammonia is given. GaP–based device exhibit sufficient response to the ammonia presence with the detection limit lower than 2.5 ppm.

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Šetka, Milena, Jana Drbohlavová, and Jaromír Hubálek. "Nanostructured Polypyrrole-Based Ammonia and Volatile Organic Compound Sensors." Sensors 17, no. 3 (March 10, 2017): 562. http://dx.doi.org/10.3390/s17030562.

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Fokin, V. N., Yu M. Shul’ga, B. P. Tarasov, E. E. Fokina, I. I. Korobov, A. G. Burlakova, and S. P. Shilkin. "Reaction of the Intermetallic Compound SmFe11Ti with Gaseous Ammonia." Russian Journal of General Chemistry 75, no. 6 (June 2005): 831–34. http://dx.doi.org/10.1007/s11176-005-0328-5.

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Bader, Ammar, Majdi M. Bkhaitan, Ashraf N. Abdalla, Qasem M. A. Abdallah, Hamed I. Ali, Dima A. Sabbah, Ghadeer Albadawi, and Ghassan M. Abushaikha. "Design and Synthesis of 4-O-Podophyllotoxin Sulfamate Derivatives as Potential Cytotoxic Agents." Evidence-Based Complementary and Alternative Medicine 2021 (January 25, 2021): 1–7. http://dx.doi.org/10.1155/2021/6672807.

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4-O-Podophyllotoxin sulfamate derivatives were prepared using the natural lignan podophyllotoxin. The prepared compounds were afforded by reacting O-sulfonyl chloride podophyllotoxin with ammonia or aminoaryl/heteroaryl motif. Biological evaluation was performed in human breast cancer (MCF7), ovarian cancer (A2780), colon adenocarcinoma (HT29), and normal lung fibroblast (MRC5) cell lines. Compound 3 exhibited potent inhibitory activity and good selectivity margin. Compounds 2, 3, and 7 exerted apoptotic effect in MCF7 cells in a dose-dependent manner. The cytotoxicity of the verified compounds was inferior to that of podophyllotoxin.

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Knettel, Doris, Markus Reil, and Nikolaus Korber. "Darstellung und Strukturaufklärung von Tricäsiumundecaphosphid- Ammoniakat(1/3) Cs3P11 · 3 NH3 / Synthesis and Crystal Structure of Tricesium Undecaphosphide-Ammonia(l/3) Cs3P11 · 3 NH3." Zeitschrift für Naturforschung B 56, no. 10 (October 1, 2001): 965–69. http://dx.doi.org/10.1515/znb-2001-1001.

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Cs3 P11 · 3 NH3 was obtained from a solution of Cs3P11 in liquid ammonia. Its structure consists of P113--cage anions, which coordinate the cesium cations together with ammonia molecules, resulting in a three-dimensional network. The compound completes a family of structures that are derived from the binary phosphide Cs3P11, through the stepwise expanding and dismantling of the three-dimensional network of ions by ammonia molecules of coordination or through the exchange of the cesium cations for voluminous molecular cations.

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Kowalchuk, George A., Zinaida S. Naoumenko, Piet J. L. Derikx, Andreas Felske, John R. Stephen, and Irina A. Arkhipchenko. "Molecular Analysis of Ammonia-Oxidizing Bacteria of the β Subdivision of the Class Proteobacteria in Compost and Composted Materials." Applied and Environmental Microbiology 65, no. 2 (February 1, 1999): 396–403. http://dx.doi.org/10.1128/aem.65.2.396-403.1999.

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ABSTRACT Although the practice of composting animal wastes for use as biofertilizers has increased in recent years, little is known about the microorganisms responsible for the nitrogen transformations which occur in compost and during the composting process. Ammonia is the principle available nitrogenous compound in composting material, and the conversion of this compound to nitrite in the environment by chemolithotrophic ammonia-oxidizing bacteria is an essential step in nitrogen cycling. Therefore, the distribution of ammonia-oxidizing members of the β subdivision of the class Proteobacteriain a variety of composting materials was assessed by amplifying 16S ribosomal DNA (rDNA) and 16S rRNA by PCR and reverse transcriptase PCR (RT-PCR), respectively. The PCR and RT-PCR products were separated by denaturing gradient gel electrophoresis (DGGE) and were identified by hybridization with a hierarchical set of oligonucleotide probes designed to detect ammonia oxidizer-like sequence clusters in the genera Nitrosospira and Nitrosomonas. Ammonia oxidizer-like 16S rDNA was detected in almost all of the materials tested, including industrial and experimental composts, manure, and commercial biofertilizers. A comparison of the DGGE and hybridization results after specific PCR and RT-PCR suggested that not all of the different ammonia oxidizer groups detected in compost are equally active. amoA, the gene encoding the active-site-containing subunit of ammonia monooxygenase, was also targeted by PCR, and template concentrations were estimated by competitive PCR. Detection of ammonia-oxidizing bacteria in the composts tested suggested that such materials may not be biologically inert with respect to nitrification and that the fate of nitrogen during composting and compost storage may be affected by the presence of these organisms.

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Suzuki, Norimichi, Hiroko Nakaoka, Akifumi Eguchi, Masamichi Hanazato, Yoshitake Nakayama, Kayo Tsumura, Kohki Takaguchi, Kazunari Takaya, Emiko Todaka, and Chisato Mori. "Concentrations of Formic Acid, Acetic Acid, and Ammonia in Newly Constructed Houses." International Journal of Environmental Research and Public Health 17, no. 6 (March 16, 2020): 1940. http://dx.doi.org/10.3390/ijerph17061940.

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Herein, the concentrations of formic acid, acetic acid, and ammonia in samples of indoor air for 47 new houses were measured two weeks after completion. The houses were fabricated with light-gauge steel structures. The measurements were performed in living rooms and bedrooms without furniture and outdoors. Air samples were analyzed using ion chromatography. The mean values were 28 (living room), 30 (bedroom), and 20 μg m−3 (outdoor air) for formic acid; 166 (living room), 151 (bedroom), and 51 μg m−3 (outdoor air) for acetic acid; and 73 (living room), 76 (bedroom), and 21 μg m−3 (outdoor air) for ammonia. The total values of the three substances accounted for 39.4–40.7% of the sum of chemical compound values. The analyzed compounds were indicated by two principal components (PC), PC1 (30.1%) and PC2 (9%), with 39.1% total variance. Formic acid, acetic acid, and ammonia were positively aligned with PC1 and negatively aligned with PC2. Factors such as room temperature, aldehydes, and phthalates were positively aligned with PC1 and negatively aligned with PC2. Furthermore, concentrations of formic acid, acetic acid, and ammonia were significantly and positively correlated with room temperature (p < 0.05).

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Ovsyannikov, Dmitry, and Vadim Lashchenov. "Comparison of Complex Formation Mechanisms in Hydrogen Abstraction Reaction between the Nitro Compound and Ammonia." Proceedings 9, no. 1 (November 14, 2018): 27. http://dx.doi.org/10.3390/ecsoc-22-05771.

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The present work aims to compare two possible pathways of a pre-reaction complex in the reaction of transfer of a hydrogen atom from ammonia to a nitro compound forming. Nitrobenzene, nitromethane, and HNO2 were used as nitro compounds. The proposed paths are: nitro compound intersystem crossing with a subsequent search for a substrate, or the formation of a complex with its subsequent excitation. The calculations were performed using TDPBE0/TDA/aug-cc-pVDZ method in NWChem-6.8 program. For verification purposes, some additional calculations were performed using RASCI/aug-cc-pVDZ method in PSI4 program. The location of the levels and the geometry of the complexes shows that the triplet complex (exciplex) is more stable than the singlet complex. The weak coupling between molecules in the singlet complex indicates that the probability of its excitation is very small. Moreover, there are experimental data, where the quantum yields of such reactions reach 0.3. The presented calculations confirm the mechanism of the nitro compound intersystem crossing with a subsequent search for a substrate.

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Rizki, Nuzulul Anggi, Mohammad Masykuri, and Retno Rosariastuti. "Application of Microbial Fuel Cell (MFC) for Bioremediation of Ammonia." Journal of Biomimetics, Biomaterials and Biomedical Engineering 62 (October 24, 2023): 63–69. http://dx.doi.org/10.4028/p-2jima9.

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Ammonia is a poisonous compound that can harm fish. Fish feed and manure are the primary sources of ammonia in catfish farming ponds. High concentrations of ammonia can cause death. Therefore, it is necessary to control the presence of ammonia to minimize the potential for fish mortality. Microbial Fuel Cell (MFC) is a technology that can help with ammonia bioremediation. This study aims to analyze the effectiveness of Microbial Fuel Cell (MFC) in reducing ammonia. The research method used is an experimental research method with qualitative descriptive analysis. The research was conducted on a laboratory scale using a dual-chamber Microbial Fuel Cell (MFC) reactor connected using a salt bridge. This research was conducted with variations in the use of sticky media, including without media, with bioball, and with bioring media. The results showed that the percentage of ammonia reduction in each treatment was 94.52%, 98.09%, and 99.28%. From this research, it can be concluded that Microbial Fuel Cells (MFC) are effective in reducing ammonia.

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Chernyak, V., V. Iukhymenko, K. Iukhymenko, O. Prysiazhna, D. Hamazin, E. Oberemok, V. Kyslenko, and A. Liptuga. "Plasma Activated Synthesis of Macromolecular Compound." PLASMA PHYSICS AND TECHNOLOGY 7, no. 1 (March 4, 2020): 6–9. http://dx.doi.org/10.14311/ppt.2020.1.6.

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The paper is devoted to study of the plasma-activated synthesis of organic compounds with optically activity. Synthesis was carried out in plasma-liquid system with a rotating gliding discharge submerged in a liquid. The initial reagents of synthesis were ethanol, ammonia, and CO<sub>2</sub>. The possibility of the inﬂuence of the electric ﬁeld direction on the optical activity of the products of plasma-activated synthesis is shown.

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Béres, Kende Attila, Fanni Szilágyi, Zoltán Homonnay, Zsolt Dürvanger, Laura Bereczki, László Trif, Vladimir M. Petruševski, Attila Farkas, Niloofar Bayat, and László Kótai. "Structural, Spectroscopic, and Thermal Decomposition Features of [Carbonatotetraamminecobalt(III)] Iodide—Insight into the Simultaneous Solid-Phase Quasi-Intramolecular Redox Reactions." Inorganics 11, no. 2 (February 1, 2023): 68. http://dx.doi.org/10.3390/inorganics11020068.

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[κ2-O,O′-Carbonatotetraamminecobalt(III)] iodide, or [Co(NH3)4CO3]I, named in this paper as compound 1, was prepared and characterized comprehensively with spectroscopic (IR, Raman and UV) and single-crystal X-ray diffraction methods. Compound 1 was orthorhombic, and isomorphous with the analogous bromide. The four ammonia ligands and the carbonate anion were coordinated to the central cobalt cation in a distorted octahedral geometry. The carbonate ion formed a four-membered symmetric planar chelate ring. The complex cations were bound to each other by N-H···O hydrogen bonds and formed zigzag sheets via an extended 2D hydrogen bond network. The complex cations and iodide ions were arranged into ion pairs and each cation bound its iodide pair through three hydrogen bonds. The thermal decomposition started with the oxidation of the iodide ion by CoIII in the solid phase resulting in [Co(NH3)4CO3] and I2. This intermediate CoII-complex in situ decomposed into Co3O4 and C-N bond containing intermediates. In inert atmosphere, CO or C-N bond containing compounds, and also, due to the in situ decomposition of CoCO3 intermediate, Co3O4 was formed. The quasi-intramolecular solid-phase redox reaction of [Co(NH3)4CO3] might have resulted in the formation of C-N bond containing compounds with substoichiometric release of ammonia and CO2 from compound 1. The C-N bond containing intermediates reduced Co3O4 into CoO and Co, whereas in oxygen-containing atmosphere, the end-product was Co3O4, even at 200 °C, and the endothermic ligand loss reaction coincided with the consecutive exothermic oxidation processes.

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Namdeo, Pratibha, Arpan Bhardwaj, and S. K. Verma. "SYNTHESIS OF MIXED LIGAND METAL COMPLEX OF CU (II) WITH SCHIFF BASE AND THIOACETAMIDE." International Journal of Engineering Technologies and Management Research 4, no. 12 (April 23, 2020): 24–26. http://dx.doi.org/10.29121/ijetmr.v4.i12.2017.587.

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Complex compounds were identified in the 19th century. The formation of hexammine cobalt(III) chloride [CO (NH3)6] Cl3 which is prepared from cobalt chloride and ammonia is thefirst compound, studied and real beginning of coordination Chemistry [1]. Alfred Werner firstexplained the nature of bonding and structure of these complexes and he was awarded NoblePrize in 1913 [2]. He gave the concept of primary (ionisable) valency and secondary(unionsible) valencies of metal ion.

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James, W. J., L. Jagat, Q. Cai, W. B. Yelon, and J. B. Yang. "Structural Study on Ammonia Borane for Hydrogen Storage." Materials Science Forum 610-613 (January 2009): 425–30. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.425.

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Ammonia borane(BH3NH3) is a promising hydrogen storage material because of its high gravimetric (19.6 wt% H2) and volumetric hydrogen density with an accompanying moderate decomposition temperature. Previously reported structures determined by using x-ray and neutron diffraction on hydrides show differences in bond lengths and atomic coordination. Here, the crystal structures of fully and half deuterated ammonia borane were investigated as a function of temperature using powder neutron diffraction. The neutron diffraction patterns show a significant difference due to large difference in the scattering length of D and H. It is evident that an order-disorder phase transition occurs around 225 K for all compounds. At low temperature, the compound crystallizes in the orthorhombic structure with space group Pnm21 and gradually transforms to a high temperature disordered tetragonal structure with space group I/4mm at about 225K. The differential scanning calorimetry studies confirm this phase transformation and also indicate that all compounds melt and decompose at above 370 K. The c cell parameter remains unchanged in the orthorhombic phase from 16 K to 200K and increases liaa nearly above 225K. As the temperature is increased, the BH3-NH3 groups start to reorient along the c axis, and the D/H atoms become disordered, leading to the tetragonal phase transition around 225K.

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Colodrero, Rosario, Inés Salcedo, Montse Bazaga-García, Eleni Barouda, Maria Papadaki, Konstantinos Papathanasiou, Daniel Hernández-Alonso, et al. "High-Throughput Synthesis of Pillared-Layered Magnesium Tetraphosphonate Coordination Polymers: Framework Interconversions and Proton Conductivity Studies." Inorganics 6, no. 3 (September 11, 2018): 96. http://dx.doi.org/10.3390/inorganics6030096.

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Novel pillared-layered framework materials were synthesized by high-throughput or microwave-assisted methodology that contain Mg2+ and the zwitterionic linker HDTMP (hexamethylenediamine-N,N,N′,N′-tetrakis(methylenephosphonic acid)). Three compounds were structurally characterized by X-ray powder diffraction. In the compound {Mg[(HO3PCH2)2N(CH2)6N(CH2PO3H2)2]·(H2O)}n(1), obtained at 140 °C by hydrothermal or microwave-assisted reaction, the layers are built by isolated Mg2+ octahedra coordinated by oxygen atoms from six different zwitterionic HDTMP ligands. Each amino-bis(methylenephosphonate) moiety links three Mg2+ ions, bridging two of them through one phosphonate group and connecting the third polyhedron in a monodentate fashion. In Compound 2, {Mg[(HO3PCH2)2N(CH2)6N(CH2PO3H2)2]}n, hydrothermally synthesized at 180 °C, the layers are composed of bidentate amino-bis(methylenephosphonate) moieties connected to three Mg2+ ions, with one of the phosphonate groups acting as a bridging ligand. Various subtle structural changes are noted for the other two compounds. Thermodiffraction of 1 reveals that a crystalline-to-crystalline phase transformation occurs concomitantly with its dehydration, leading to a new anhydrous phase, namely, {Mg[(HO3PCH2)2N(CH2)6N(CH2PO3H2)2]}n(1deh). This process is fully reversible upon equilibrating the solid at room temperature. The reported compounds can adsorb ammonia and CO2. Compound 1 exhibits a moderate proton conductivity, ~1.5 × 10−5 S·cm−1 at 80 °C and 95% RH, that increases a half order of magnitude after experiencing a complete dehydration/rehydration process, 1→1deh→1.

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Ray, Hannah, Francois Perreault, and Treavor H. Boyer. "Ammonia recovery and fouling mitigation of hydrolyzed human urine treated by nanofiltration and reverse osmosis." Environmental Science: Water Research & Technology 8, no. 2 (2022): 429–42. http://dx.doi.org/10.1039/d1ew00601k.

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Gao, Peifeng. "Progress of ammonia electro-oxidation catalysts for direct ammonia alkaline fuel cells." Highlights in Science, Engineering and Technology 43 (April 14, 2023): 340–49. http://dx.doi.org/10.54097/hset.v43i.7439.

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At present, hydrogen fuel cells are one of the effective means to solve energy and environmental problems, but the problem of hydrogen storage and transportation is difficult to break through. Ammonia is a carbon-free hydrogen-rich compound, which also has the advantages of high bulk density and easy storage and transportation, and is an ideal fuel to replace hydrogen as a battery. However, at present, the preferred ammonia electro-oxidation catalyst for direct ammonia alkaline fuel cells is still platinum, and its expensive price is the main problem that hinders the wide application of direct ammonia alkaline fuel cells. Therefore, the design of low-cost and high-efficiency catalysts is a necessary task for commercializing direct ammonia fuel cells. In this paper, we firstly review the progress of researchers in ammonia electrooxidation mechanism in recent years, focus on reviewing the current research status of Pt catalysts and non-Pt catalysts for direct ammonia alkaline fuel cells, and finally suggest future research approaches to address the existing problems, aiming to provide ideas for designing more efficient, stable and cheap ammonia electrooxidation catalysts in the future.

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Estevez, Rafael, Francisco J. López-Tenllado, Laura Aguado-Deblas, Felipa M. Bautista, Antonio A. Romero, and Diego Luna. "Current Research on Green Ammonia (NH3) as a Potential Vector Energy for Power Storage and Engine Fuels: A Review." Energies 16, no. 14 (July 18, 2023): 5451. http://dx.doi.org/10.3390/en16145451.

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Considering the renewable electricity production using sustainable technologies, such as solar photovoltaics or wind turbines, it is essential to have systems that allow for storing the energy produced during the periods of lower consumption as well as the energy transportation through the distribution network. Despite hydrogen being considered a good candidate, it presents several problems related to its extremely low density, which requires the use of very high pressures to store it. In addition, its energy density in volumetric terms is still clearly lower than that of most liquid fuels. These facts have led to the consideration of ammonia as an alternative compound for energy storage or as a carrier. In this sense, this review deals with the evaluation of using green ammonia for different energetic purposes, such as an energy carrier vector, an electricity generator and E-fuel. In addition, this study has addressed the latest studies that propose the use of nitrogen-derived compounds, i.e., urea, hydrazine, ammonium nitrate, etc., as alternative fuels. In this study, the possibility of using other nitrogen-derived compounds, i.e., an update of the ecosystem surrounding green ammonia, has been assessed, from production to consumption, including storage, transportation, etc. Additionally, the future challenges in achieving a technical and economically viable energy transition have been determined.

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Fan, Li Sha, Yan Zhen Yu, and Chun Hui Zhao. "Preparation of Compound Clinoptilolite Filter Material and Performance of Ammonia Nitrogen Removal." Advanced Materials Research 830 (October 2013): 24–27. http://dx.doi.org/10.4028/www.scientific.net/amr.830.24.

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This experiment use natural clinoptilolite powder as main materials to prepare the large specific surface and high porosity spherical compound filter material by adding adhesive and pore-forming agent etc.This compound filter material has favourable effect when treating sanitary wastewater. The static adsorption test showed that the absorption ratio of ammonia-nitrogen is 58.5% when the compound filter material dosage was 100g/L, NH4+-N concentration was 100mg/L and the contact time was 40min.The cure fitting of the adsorption isotherm of NH4+-N on the compound filter material could be well described by the Langmuir formula and R2 (the coefficient of determination) is 0.99216. At the stably running phase, when the average concentrations of influent NH3-N was 35mg/L, the average removal ratio and concentration of effluent NH4+-N reached 83.51% and 5.81mg/L which could meet the first degree of national wastewater discharge standard (GB 8978-1996).

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Ramazonova, Dilbar, Zokirjon Turayev, Bakhodir Mamurov, Aisholpan Shamishova, Diyorbek Absattorov, Ilkham Usmanov, and Murodjon Samadiy. "Study of a Copper Microelement Compound Formed in Ammophosis Pulp." E3S Web of Conferences 411 (2023): 01046. http://dx.doi.org/10.1051/e3sconf/202341101046.

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The results of physicochemical analyzes of the compound CuNH4 PO4 ∙ H2O isolated from ammophos pulp at pH 6.58 obtained by neutralization of phosphoric acid containing copper sulfate as a trace element with gaseous ammonia are presented. The compound was found to have the formula [Cu (NH3) (H2O) HPO4]. The parameters of the N–H bond for the coordinated amino group were calculated: force constant, bond angle, and interatomic distance. In the transition from the electronic spectrum of the reflection of copper hydrophosphate monohydrate to the spectrum of copper ammonium phosphate monohydrate, a hypochromic shift of a maximum of 74 nm is observed, which indicates the entry of an ammonia molecule into the composition of copper monoaquahydrophosphate with the formation of copper monoaquaaminehydrophosphate. This is confirmed by the absence of an intense wide band at 3100-2900 sm- 1 characteristic of the ammonium cation in the IR spectrum.

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Mostafa, Nagwan G., Ahmed G. Radwan, and Mona M. Galal. "Two-Dimensional Steady-State Analysis of Selected Wastewater State Variables Using ASM3." International Journal of Engineering Research in Africa 54 (June 2021): 176–86. http://dx.doi.org/10.4028/www.scientific.net/jera.54.176.

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Performance of activated sludge wastewater treatment plants are mainly dependent on bacterial growth, which is limited by many factors. These factors include availability of suitable substrate, limiting nutrients, environmental conditions, and energy. In activated sludge model no. 3 (ASM3), constituents in wastewater are divided into two main categories: carbonaceous compounds and nitrogenous compounds, which are further subdivided depending on their solubility and biodegradability. These compounds are not mutually independent; hence, the fate of one compound in the biological processes is affected by one or more of the other compounds. In this study, a steady-state analysis was conducted to investigate the effect of initial readily biodegradable substrate, oxygen, ammonia nitrogen, nitrite plus nitrate, and heterotrophic organisms’ concentrations on the effluent concentrations of readily biodegradable COD and nitrogen compounds. The studied ranges of the selected wastewater state variables were identified based on literature surveys including previous studies concerning domestic, industrial, and synthetic wastewaters. The results proved that the effluent readily biodegradable substrate and ammonia nitrogen concentrations are reduced as the initial dissolved oxygen and nitrite plus nitrate concentrations are increased. Moreover, better nitrification-denitrification process is achieved at lower initial readily biodegradable concentration leading to lower nitrite plus nitrate concentrations.

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Baki, Touhami. "Pool Boiling of Ammonia, Assessment of Correlations." International Journal of Air-Conditioning and Refrigeration 29, no. 02 (March 31, 2021): 2150012. http://dx.doi.org/10.1142/s2010132521500127.

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Ammonia is a natural compound, used more and more in refrigeration installations of absorption and vapor compression, component sizing and more particularly evaporators pass by the mastery and prediction of heat transfer. Our study aims to retrieve experimental data from the literature and verify them with known author correlations, and the differences were observed with margins of error; a new correlation has been developed giving convincing results.

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Ploszajski, Anna R., Matthew Billing, Neal T. Skipper, and Jeremy K. Cockcroft. "A novel ammonium pentaborate – poly(ethylene-glycol) templated polymer-inclusion compound." Chemical Communications 55, no. 57 (2019): 8290–92. http://dx.doi.org/10.1039/c9cc02720c.

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Reaction of ammonia borane with poly-ethylene glycol at slightly elevated temperatures leads to the formation of the first known example of a borate-based polymer inclusion compound with a pentaborate framework structure.

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Li, Shan Ping, Wei Yang, and Jing Fu. "Preparation and Application of Slag Compound Flocculant." Advanced Materials Research 148-149 (October 2010): 1523–27. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1523.

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A new kind of composite flocculant, polyaluminum ferric chloride (PAFC), was prepared using blast furnace dust and scrap material of aluminum. Tests about its application on the treatment of brewing wastewater were carried out and the flocculation mechanism was discussed. Results showed that the best condition for foluccation was: doses of PAFC was 40 mg/L, pH of wastewater was about 7.0, sedimentation time was 30 min, removal rate of turbidity, CODcr, decolorization and ammonia were 96.8%、64.7%、87.5% and 41.0% respectively.

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Żółciak, Tadeusz, and Zbigniew Łataś. "Ammonia dilution during nitriding and carbonitridingin a fluidized bed of 41CrAlMo7 constructional steel." Inżynieria Powierzchni 24, no. 3 (December 5, 2019): 34–41. http://dx.doi.org/10.5604/01.3001.0013.5787.

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Nitriding of 41CrAlMo7 steel was carried out in a fluidized bed of aluminum oxide at a constant temperature of 570oC/4h in ammonia with technical nitrogen or with nitrogen-hydrogen mixture. Carbonitriding was carried out in ammonia with technical nitrogen for two different carbon carriers. In addition, one process was carried out in ammonia with the addition of 5% propane. The influence of diluting ammonia with pure and technical nitrogen upon the hardness and thickness of the nitrided layer was investigated. The hardness and thickness of the carbonitrided layer in ammonia with technical nitrogen and natural gas or carbon dioxide were compared with the parameters of the layer carbonitrided in ammonia and propan. High surface hardness and thickness of the nitrided layer were obtained with the participation of 70% of pure nitrogen or 30% of technical nitrogen in a mixture with ammonia after preliminary oxidation at 350oC/ 30min in air. In case of carbonitriding, the highest hardness and thickness of the nitrided layer were obtained in a mixture of ammonia with and the addition of 5% propane, and the highest thickness of the nitride compound zone in a mixture of ammonia and technical nitrogen with the addition of natural gas or carbon dioxide.

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Kraus, Florian, and Sebastian A. Baer. "Tetraammine Tetrafluorido Cerium(IV) Ammonia (1/1), [CeF4(NH3)4] · NH3." Zeitschrift für Naturforschung B 66, no. 8 (August 1, 2011): 868–70. http://dx.doi.org/10.1515/znb-2011-0815.

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The synthesis and crystal structure of the first ammine complex of a cerium fluoride, tetraammine tetrafluorido cerium(IV) ammonia (1/1), [CeF4(NH3)4] ・NH3, are presented. The compound crystallizes in the form of colorless, block-shaped single crystals in the tetragonal space group P4/ncc with a = 9.03215(9), c = 10.96404(17) Å , V = 894.443(19) Å3, and Z = 4. The compound contains discrete [CeF4(NH3)4] molecules interconnected by N-H···F hydrogen bonds.

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Hendriksen, Peter Vang, Xiufu Sun, Francesco Mondi, Patricia Rabelo Monich, Stéven Pirou, and Henrik Lund Frandsen. "Electrochemical Cells for Novel Routes to Ammonia." ECS Transactions 111, no. 6 (May 19, 2023): 1611–21. http://dx.doi.org/10.1149/11106.1611ecst.

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Ammonia is an extremely important chemical compound. The conventional production route is CO2 intensive and almost 2% of global anthropogenic CO2 emissions stems from ammonia synthesis. This will have to change over the coming decades to reduce negative impact on the climate and ensure a green route to ammonia. Here, a novel way to provide the synthesis gas mixture for ammonia synthesis is suggested based on combining an SOEC to provide the hydrogen with a dedicated cell to provide also nitrogen for the process. This is suggested to be achieved by electrochemically pumping out oxygen from an air stream. Cells were successfully developed and characterized for this purpose. Exit streams with more than 98% nitrogen purity were documented and the developed cells were shown to be stable over test periods exceeding 3000 hours of operation.

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Paromov, Artyom E. "Condensation of Benzyl Carbamate with Glyoxal in Polar Protic and Aprotic Solvents." Molecules 28, no. 22 (November 17, 2023): 7648. http://dx.doi.org/10.3390/molecules28227648.

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The synthesis of substituted 2,4,6,8,10,12-hexaazaisowurtzitane via direct condensation is challenging. The selection of starting ammonia derivatives is very limited. The important step in developing alternative synthetic routes to these compounds is to investigate their formation process in detail. Here, we examined an acid-catalyzed condensation between benzyl carbamate and glyoxal in a ratio of 2:1 in a range of polar protic and aprotic solvents, and discovered a new process occurring during the cascade condensation of glyoxal with ammonia derivatives as well as discovered several processes hindering the formation of caged compounds. More specifically, a cyclic compound, N,N′-bis(carbobenzoxy)-3,6-diamino-1,4-dioxane-2,5-diol, was found to form at the early stage of condensation under low acidity conditions. The formation of this compound is governed by an easier condensation of alcohol groups compared to the amide ones. The condensation intermediates, N,N′-bis(carbobenzoxy)ethan-1,2-diol, N,N′,N″-tris(carbobenzoxy)ethanol, and N,N′,N″,N‴-tetrakis(carbobenzoxy)ethan, were obtained at a higher acidity. A range of solvents were identified: those that react with benzyl carbamate, those that promote the progress of side processes, and those that promote precipitation of condensation intermediates. A few byproducts were isolated and identified. It was found that DMSO exhibits a strong deactivating ability, while CH3CN exhibits a strong activating ability towards the acid-catalyzed condensation process of benzyl carbamate with glyoxal.

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Erfkamp, Jan, Margarita Guenther, and Gerald Gerlach. "Piezoresistive Hydrogel-Based Sensors for the Detection of Ammonia." Sensors 19, no. 4 (February 25, 2019): 971. http://dx.doi.org/10.3390/s19040971.

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Ammonia is an essential key compound in the chemical industry. However, excessively high ammonia concentrations can be harmful to the environment. Sensors for the detection of ammonia are therefore particularly important for environmental analysis. In this article, a novel hydrogel-based piezoresistive ammonia sensor is presented. In aqueous solution, ammonia reacts as a base. This alkaline pH change can be detected with stimuli-sensitive hydrogels. For such an application, highly sensitive hydrogels in the alkaline range with sufficient mechanical stability for the sensor application has to be developed. These conditions are fulfilled by the presented hydrogel system based on acrylic acid (AAc) and 2-(dimethylamino)ethyl methacrylate (DMAEMA). The hydrogel composition has a significant influence on the swelling behavior of the gel. Furthermore, the hydrogel swelling in ammonia solutions was tested and a detection limit in the range of 1 mmol/L ammonia depending on the buffer solution was determined. Ammonia-sensitive hydrogels can be used multiple times due to the repeatable swelling of the gel over several swelling cycles. To generate a measurable output voltage, the swelling pressure of ammonia-sensitive hydrogels were detected by using piezoresistive pressure sensors. All results of the free hydrogel swelling were verified in the sensor application. This low-cost ammonia sensor with a high sensitivity could be interesting for industrial chemical and biotechnological applications.

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50

Zhao, Jian-Shen, Ajay Singh, Xiao-Dong Huang, and Owen P. Ward. "Biotransformation of Hydroxylaminobenzene and Aminophenol by Pseudomonas putida 2NP8 Cells Grown in the Presence of 3-Nitrophenol." Applied and Environmental Microbiology 66, no. 6 (June 1, 2000): 2336–42. http://dx.doi.org/10.1128/aem.66.6.2336-2342.2000.

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ABSTRACT Biotransformation products of hydroxylaminobenzene and aminophenol produced by 3-nitrophenol-grown cells of Pseudomonas putida2NP8, a strain grown on 2- and 3-nitrophenol, were characterized. Ammonia, 2-aminophenol, 4-aminophenol, 4-benzoquinone,N-acetyl-4-aminophenol, N-acetyl-2-aminophenol, 2-aminophenoxazine-3-one, 4-hydroquinone, and catechol were produced from hydroxylaminobenzene. Ammonia, N-acetyl-2-aminophenol, and 2-aminophenoxazine-3-one were produced from 2-aminophenol. All of these metabolites were also found in the nitrobenzene transformation medium, and this demonstrated that they were metabolites of nitrobenzene transformation via hydroxylaminobenzene. Production of 2-aminophenoxazine-3-one indicated that oxidation of 2-aminophenol via imine occurred. Rapid release of ammonia from 2-aminophenol transformation indicated that hydrolysis of the imine intermediate was the dominant reaction. The low level of 2-aminophenoxazine-3-one indicated that formation of this compound was probably due to a spontaneous reaction accompanying oxidation of 2-aminophenol via imine. 4-Hydroquinone and catechol were reduction products of 2- and 4-benzoquinones. Based on these transformation products, we propose a new ammonia release pathway via oxidation of aminophenol to benzoquinone monoimine and subsequent hydrolysis for transformation of nitroaromatic compounds by 3-nitrophenol-grown cells of P. putida 2NP8. We propose a parallel mechanism for 3-nitrophenol degradation in P. putida 2NP8, in which all of the possible intermediates are postulated.

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Journal articles on the topic 'Ammonia compound'

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