40 CFR 721.3625 - Fatty acid amine salt (generic name).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid amine salt (generic name... Substances § 721.3625 Fatty acid amine salt (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as fatty acid amine salt (PMN P-88...

40 CFR 721.3625 - Fatty acid amine salt (generic name).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acid amine salt (generic name... Substances § 721.3625 Fatty acid amine salt (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as fatty acid amine salt (PMN P-88...

Halide salts and their structural properties in presence of secondary amine based molecule: A combined experimental and theoretical analysis

NASA Astrophysics Data System (ADS)

Ghosh, Pritam; Hazra, Abhijit; Ghosh, Meenakshi; Chandra Murmu, Naresh; Banerjee, Priyabrata

2018-04-01

Biologically relevant halide salts and its solution state structural properties are always been significant. In general, exposure of halide salts into polar solution medium results in solvation which in turn separates the cationic and anionic part of the salt. However, the conventional behaviour of salts might alter in presence of any secondary amine based compound, i.e.; moderately strong Lewis acid. In its consequence, to investigate the effect of secondary amine based compound in the salt solution, novel (E)-2-(4-bromobenzylidene)-1-(perfluorophenyl) hydrazine has been synthesized and used as secondary amine source. The secondary amine compound interestingly shows a drastic color change upon exposure to fluoride salts owing to hydrogen bonding interaction. Several experimental methods, e.g.; SCXRD, UV-Vis, FT-IR, ESI-MS and DLS together with modern DFT (i.e.; DFT-D3) have been performed to explore the structural properties of the halide salts upon exposure to secondary amine based compound. The effect of counter cation of the fluoride salt in binding with secondary amine source has also been investigated.

40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate, amine...

40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate, amine...

Enhancing Skin Permeation of Biphenylacetic Acid (BPA) Using Salt Formation with Organic and Alkali Metal Bases

PubMed Central

Pawar, Vijay; Naik, Prashant; Giridhar, Rajani; Yadav, Mange Ram

2015-01-01

In the present study, a series of organic and alkali metal salts of biphenylacetic acid (BPA) have been prepared and evaluated in vitro for percutaneous drug delivery. The physicochemical properties of BPA salts were determined using solubility measurements, DSC, and IR. The DSC thermogram and FTIR spectra confirmed the salt formation with organic and alkali metal bases. Among the series, salts with organic amines (ethanolamine, diethanolamine, triethanolamine, and diethylamine) had lowered melting points while the alkali metal salt (sodium) had a higher melting point than BPA. The in vitro study showed that salt formation improves the physicochemical properties of BPA, leading to improved permeability through the skin. Amongst all the prepared salts, ethanolamine salt (1b) showed 7.2- and 5.4-fold higher skin permeation than the parent drug at pH 7.4 and 5.0, respectively, using rat skin. PMID:26839810

40 CFR 721.3620 - Fatty acid amine condensate, polycarboxylic acid salts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid amine condensate... Specific Chemical Substances § 721.3620 Fatty acid amine condensate, polycarboxylic acid salts. (a... a fatty acid amine condensate, polycarboxylic acid salts. (PMN P-92-445) is subject to reporting...

40 CFR 721.643 - Ethoxylated alcohol, phosphated, amine salt.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Ethoxylated alcohol, phosphated, amine... Specific Chemical Substances § 721.643 Ethoxylated alcohol, phosphated, amine salt. (a) Chemical substance... alcohol, phosphated, amine salt (PMN P-96-1478) is subject to reporting under this section for the...

40 CFR 721.3620 - Fatty acid amine condensate, polycarboxylic acid salts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acid amine condensate... Specific Chemical Substances § 721.3620 Fatty acid amine condensate, polycarboxylic acid salts. (a... a fatty acid amine condensate, polycarboxylic acid salts. (PMN P-92-445) is subject to reporting...

Amine enriched solid sorbents for carbon dioxide capture

DOEpatents

Gray, McMahan L.; Soong, Yee; Champagne, Kenneth J.

2003-04-15

A new method for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The new method entails treating a solid substrate with acid or base and simultaneous or subsequent treatment with a substituted amine salt. The method eliminates the need for organic solvents and polymeric materials for the preparation of CO.sub.2 capture systems.

X-Ray Crystallography Analysis of Complexes Synthesized with Tris(2-pyridylmethyl)amine: A Laboratory Experiment for Undergraduate Students Integrating Interdisciplinary Concepts and Techniques

ERIC Educational Resources Information Center

Bazley, Isabel J.; Erie, Ellen A.; Feiereisel, Garrett M.; LeWarne, Christopher J.; Peterson, Jack M.; Sandquist, Katherine L.; Oshin, Kayode D.; Zeller, Matthias

2018-01-01

An integrated laboratory experiment applying concepts and techniques from organic chemistry, inorganic chemistry, and instrumental analysis is presented for use in the undergraduate curriculum. This experiment highlights the synthesis, characterization, and use of tris(2-pyridylmethyl)amine (TPMA) to make complexes with different metal salts. It…

Reactive Uptake of Dimethylamine by Ammonium Sulfate and Ammonium Sulfate-Sucrose Mixed Particles.

PubMed

Chu, Yangxi; Chan, Chak K

2017-01-12

Short-chain alkyl amines can undergo gas-to-particle partitioning via reactive uptake by ammonium salts, whose phases have been thought to largely influence the extent of amine uptake. Previous studies mainly focused on particles of single ammonium salt at either dry or wet conditions without any addition of organic compounds. Here we report the uptake of dimethylamine (DMA) by ammonium sulfate (AS) and AS-sucrose mixed particles at different relative humidities (RHs) using an electrodynamic balance coupled with in situ Raman spectroscopy. DMA is selected as a representative of short-chain alkyl amines, and sucrose is used as a surrogate of viscous and hydrophilic organics. Effective DMA uptake was observed for most cases, except for the water-limiting scenario at <5% RH and the formation of an ultraviscous sucrose coating at 10% RH and below. DMA uptake coefficients (γ) were estimated using the particle mass measurements during DMA uptake. Addition of sucrose can increase γ by absorbing water or inhibiting AS crystallization and decrease γ by elevating the particle viscosity and forming a coating layer. DMA uptake can be facilitated for crystalline AS or retarded for aqueous AS with hydrophilic viscous organics (e.g., secondary organic material formed via the oxidation of biogenic volatile organic compounds) present in aerosol particles.

Anhydrous Proton-Conducting Membranes for Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Yen, Shiao-Pin S.

2005-01-01

Polymeric electrolyte membranes that do not depend on water for conduction of protons are undergoing development for use in fuel cells. Prior polymeric electrolyte fuel-cell membranes (e.g., those that contain perfluorosulfonic acid) depend on water and must be limited to operation below a temperature of 125 C because they retain water poorly at higher temperatures. In contrast, the present developmental anhydrous membranes are expected to function well at temperatures up to 200 C. The developmental membranes exploit a hopping-and-reorganization proton- conduction process that can occur in the solid state in organic amine salts and is similar to a proton-conduction process in a liquid. This process was studied during the 1970s, but until now, there has been no report of exploiting organic amine salts for proton conduction in fuel cells.

The Onium Compounds

NASA Astrophysics Data System (ADS)

Tsarevsky, Nicolay V.; Slaveykova, Vera; Manev, Stefan; Lazarov, Dobri

1997-06-01

The onium salts are of a big interest for theoretical and structural chemistry, and for organic synthesis. Some representatives of the group (e.g. ammonium salts) were known from the oldest times. Many onium salts are met the nature: ammonium salts (either as inorganic salts, and organic derivatives, e.g. aminoacids, salts of biogenic amines and alkaloids, etc.); oxonium salts (plant pigments as anthocyans are organic oxonium compounds), etc. In 1894 C. Hartmann and V. Meyer prepared the first iodonium salts - 4-iododiphenyliodonium hydrogensulfate and diphenyliodonium salts, and suggested the ending -onium for all compounds with properties similar to those of ammonium salts. Nowadays onium compounds of almost all nonmetals are synthesised and studied. A great variety of physical methods: diffraction (e.g. XRD) and spectral methods (IR-, NMR-, and UV-spectra), as well as the chemical properties and methods of preparation of onium salts have been used in determination of the structure of these compounds. The application of different onium salts is immense. Ammonium, phosphonium and sulfonium salts are used as phase-transfer catalysts; diazonium salts - for the preparation of dyes, metalochromic and pH-indicators. All the onium salts and especially diazonium and iodonium salts are very useful reagents in organic synthesis.

Experimental investigation and DFT calculation of different amine/ammonium salts adsorption on kaolinite

NASA Astrophysics Data System (ADS)

Chen, Jun; Min, Fan-fei; Liu, Lingyun; Liu, Chunfu; Lu, Fangqin

2017-10-01

The adsorption of four different amine/ammonium salts of DDA (Dodecyl amine), MDA (N-methyldodecyl amine), DMDA (N,N-dimethyldodecyl amine) and DTAC (Dodecyl trimethyl ammonium chloride) on kaolinite particles was investigated in the study through the measurement of contact angles, zeta potentials, aggregation observation, adsorption and sedimentation. The results show that different amine/ammonium salts can adsorb on the kaolinite surface to enhance the hydrophobicity and reduce the electronegativity of kaolinite particle surface, and thus induce a strong hydrophobic aggregation of kaolinite particles which promotes the settlement of kaolinite. To explore the adsorption mechanism of these four amine/ammonium salts on kaolinite surfaces, the adsorptions of DDA+, MDA+, DMDA+ and DTAC+ on kaolinite (001) surface and (00 1 bar) surface are calculated with DFT (Density functional theory). The DFT calculation results indicate that different amine/ammonium cations can strongly adsorbed on kaolinite (001) surface and (00 1 bar) surface by forming Nsbnd H⋯O strong hydrogen bonds or Csbnd H⋯O weak hydrogen bonds, and there are strongly electrostatic attractions between different amine/ammonium cations and kaolinite surfaces. The main adsorption mechanism of amine/ammonium cations on kaolinite is hydrogen-bond interaction and electrostatic attraction.

NO3 and OH initiated secondary aerosol formation from aliphatic amines - salt formation and effect of water vapor

USDA-ARS?s Scientific Manuscript database

Aliphatic amines enter the atmosphere from a variety of sources, and have been detected existing in gas and particle phases in the atmosphere. Similar to ammonia, amines can form inorganic salt through acid-base reactions. However, the atmospheric behavior of amines with atmospheric oxidants (e.g. n...

Study on biogenic amines in various dry salted fish consumed in China

NASA Astrophysics Data System (ADS)

Wu, Yanyan; Chen, Yufeng; Li, Laihao; Yang, Xianqing; Yang, Shaoling; Lin, Wanling; Zhao, Yongqiang; Deng, Jianchao

2016-08-01

This study was carried out to investigate the biogenic amines (BAs), physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine (CAD) and putrescine (PUT) were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret ( Pampus argenteus) (347.79 mg kg-1). Five of forty three samples exceeded the acceptable content of TYR (100 mg kg-1), and 23.26% of dried-salted fish contained high contents of biogenic amines (above 600 mg kg-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count (TPC) was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.

Crystal structures of seven molecular salts derived from benzylamine and organic acidic components

NASA Astrophysics Data System (ADS)

Wen, Xianhong; Jin, Xiunan; Lv, Chengcai; Jin, Shouwen; Zheng, Xiuqing; Liu, Bin; Wang, Daqi; Guo, Ming; Xu, Weiqiang

2017-07-01

Cocrystallization of the commonly available organic amine, benzylamine, with a series of organic acids gave a total of seven molecular salts with the compositions: (benzylamine): (p-toluenesulfonic acid) (1) [(HL)+ · (tsa-)], (benzylamine): (o-nitrobenzoic acid) (2) [(HL+) · (onba)-], (benzylamine): (3,4-methylenedioxybenzoic acid) (3) [(HL+) · (mdba-)], (benzylamine): (mandelic acid) (4) [(HL+) · (mda-)], (benzylamine): (5-bromosalicylic acid)2(5) [(HL+) · (bsac-) · (Hbsac)], (benzylamine): (m-phthalic acid) (6) [(HL+) · (Hmpta-)], and (benzylamine)2: (trimesic acid) (7) [(HL+)2 · (Htma2-)]. The seven salts have been characterised by X-ray diffraction technique, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the seven investigated crystals the NH2 groups in the benzylamine moieties are protonated when the organic acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted Nsbnd H⋯O hydrogen bond formation between the ammonium and the deprotonated acidic groups. Except the Nsbnd H⋯O hydrogen bond, the Osbnd H⋯O hydrogen bonds (charge assisted or neutral) were also found at the salts 4-7. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O/CH2sbnd O, CHsbnd π/CH2sbnd π, Osbnd O, and Osbnd Cπ associations contribute to the stabilization and expansion of the total high-dimensional (2D-3D) framework structures. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R42(8), R43(10) and R44(12), usually observed in organic solids of organic acids with amine, were again shown to be involved in constructing most of these hydrogen bonding networks.

Capillary Electrophoresis Analysis of Organic Amines and Amino Acids in Saline and Acidic Samples Using the Mars Organic Analyzer

NASA Astrophysics Data System (ADS)

Stockton, Amanda M.; Chiesl, Thomas N.; Lowenstein, Tim K.; Amashukeli, Xenia; Grunthaner, Frank; Mathies, Richard A.

2009-11-01

The Mars Organic Analyzer (MOA) has enabled the sensitive detection of amino acid and amine biomarkers in laboratory standards and in a variety of field sample tests. However, the MOA is challenged when samples are extremely acidic and saline or contain polyvalent cations. Here, we have optimized the MOA analysis, sample labeling, and sample dilution buffers to handle such challenging samples more robustly. Higher ionic strength buffer systems with pKa values near pH 9 were developed to provide better buffering capacity and salt tolerance. The addition of ethylaminediaminetetraacetic acid (EDTA) ameliorates the negative effects of multivalent cations. The optimized protocol utilizes a 75 mM borate buffer (pH 9.5) for Pacific Blue labeling of amines and amino acids. After labeling, 50 mM (final concentration) EDTA is added to samples containing divalent cations to ameliorate their effects. This optimized protocol was used to successfully analyze amino acids in a saturated brine sample from Saline Valley, California, and a subcritical water extract of a highly acidic sample from the Río Tinto, Spain. This work expands the analytical capabilities of the MOA and increases its sensitivity and robustness for samples from extraterrestrial environments that may exhibit pH and salt extremes as well as metal ions.

Capillary electrophoresis analysis of organic amines and amino acids in saline and acidic samples using the Mars organic analyzer.

PubMed

Stockton, Amanda M; Chiesl, Thomas N; Lowenstein, Tim K; Amashukeli, Xenia; Grunthaner, Frank; Mathies, Richard A

2009-11-01

The Mars Organic Analyzer (MOA) has enabled the sensitive detection of amino acid and amine biomarkers in laboratory standards and in a variety of field sample tests. However, the MOA is challenged when samples are extremely acidic and saline or contain polyvalent cations. Here, we have optimized the MOA analysis, sample labeling, and sample dilution buffers to handle such challenging samples more robustly. Higher ionic strength buffer systems with pK(a) values near pH 9 were developed to provide better buffering capacity and salt tolerance. The addition of ethylaminediaminetetraacetic acid (EDTA) ameliorates the negative effects of multivalent cations. The optimized protocol utilizes a 75 mM borate buffer (pH 9.5) for Pacific Blue labeling of amines and amino acids. After labeling, 50 mM (final concentration) EDTA is added to samples containing divalent cations to ameliorate their effects. This optimized protocol was used to successfully analyze amino acids in a saturated brine sample from Saline Valley, California, and a subcritical water extract of a highly acidic sample from the Río Tinto, Spain. This work expands the analytical capabilities of the MOA and increases its sensitivity and robustness for samples from extraterrestrial environments that may exhibit pH and salt extremes as well as metal ions.

75 FR 50891 - N-alkyl (C8-C18) Primary Amines and Acetate Salts; Exemption from the Requirement of a Tolerance

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

... alcohols and hydrocarbons; surfactants such as polyoxyethylene polymers and fatty acids; carriers such as... NAPAAS primary amines and primary amine acetate salt may also be conjugated, whether by glucuronidation...

Organic amine catalytic organosolv pretreatment of corn stover for enzymatic saccharification and high-quality lignin.

PubMed

Tang, Chenglun; Shan, Junqiang; Chen, Yanjun; Zhong, Lingxia; Shen, Tao; Zhu, Chenjie; Ying, Hanjie

2017-05-01

A novel and efficient organic amine and organosolv synergetic pretreatment method was developed to overcome the recalcitrance of lignocellulose to produce fermentable sugars and high-quality salt-free lignin. After optimization of the process parameters, a delignification of 81.7% and total sugar yield of 83.2% (87.1% glucose, 75.4% xylose) could be obtained using n-propylamine (10mmol/g, biomass) as a catalyst and aqueous ethanol (60%, v/v) as a solvent. The susceptibility of the substrates to enzymatic digestibility was explained by their physical and chemical characteristics. The physical structure of extracted lignin showed higher β-aryl ether bonds content and functionalities, offering the potential for further downstream upgrading. The role of organic amine catalyst and a synergistic mechanism is proposed for the present system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impact of salt reduction on biogenic amines, fatty acids, microbiota, texture and sensory profile in traditional blood dry-cured sausages.

PubMed

Laranjo, Marta; Gomes, Ana; Agulheiro-Santos, Ana Cristina; Potes, Maria Eduarda; Cabrita, Maria João; Garcia, Raquel; Rocha, João Miguel; Roseiro, Luísa Cristina; Fernandes, Maria José; Fraqueza, Maria João; Elias, Miguel

2017-03-01

Meat industry needs to reduce salt in their products due to health issues. The present study evaluated the effect of salt reduction from 6% to 3% in two Portuguese traditional blood dry-cured sausages. Physicochemical and microbiological parameters, biogenic amines, fatty acids and texture profiles and sensory panel evaluations were considered. Differences due to salt reduction were perceptible in a faint decline of water activity, which slightly favoured microbial growth. Total biogenic amines content ranged from 88.86 to 796.68mgkg -1 fresh matter, with higher amounts, particularly of cadaverine, histamine and tyramine, in low-salt products. Still, histamine and other vasoactive amines remained at low levels, thus not affecting consumers' health. Regarding fatty acids, no significant differences were observed due to salt. However, texture profile analysis revealed lower resilience and cohesiveness in low-salt products, although no textural changes were observed by the sensory panel. Nevertheless, low-salt sausages were clearly preferred by panellists. Copyright © 2016 Elsevier Ltd. All rights reserved.

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2010 CFR

2010-07-01

... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN P-00...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2011 CFR

2011-07-01

... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN P-00...

40 CFR 721.640 - Amine substituted metal salts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine substituted metal salts. 721.640 Section 721.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.640 Amine substituted metal...

Amine salts of nitroazoles

DOEpatents

Kienyin Lee; Stinecipher, M.M.

1993-10-26

Compositions of matter, a method of providing chemical energy by burning said compositions, and methods of making said compositions are described. These compositions are amine salts of nitroazoles. 1 figure.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasschau, M.R.; Skaggs, M.M.; Chen, E.C.M.

Stress has been reported to accelerate protein catabolism in man and animals and as a result one can expect to observe changes in certain amino acids pools of these organisms. In the present study, the Gulf Coast sea anemone, Bunodosoma cavernata, was used as the test animal and free amino acid levels of whole animals were measured following stressed conditions. Sea anemones were chosen as the test animals since they are sessile and, due to the nature of their morphology, they have few mechanisms by which they can escape environmental stress. The animals were exposed to sublethal concentrations of mercuricmore » chloride and cadmium chloride and the organic amines, aniline, diethanol amine (DEA), and ethylene diamine (EDA). Chloride salts of mercury and cadmium were chosen rather than other anions since chloride is the most abundant anion in seawater. These two particular metals were chosen as challenge compounds due to their high toxicity in aquatic systems. The three organic amines were chosen for their relatively high water solubility and low vapor pressure in an aqueous solution, thus insuring that the toxic compound is retained in the test solution. Since organic amines are used extensively in the Gulf Coast industrial complex, there is a high probability of these compounds contaminating the marine environment. Results indicate that the reaction of B. cavernata to stress from organic amines is similar to the response to heavy metals, only more extensive.« less

Methods of making organic compounds by metathesis

DOEpatents

Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John

2015-09-01

Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.

Effect of salt-tolerant yeast of Candida versatilis and Zygosaccharomyces rouxii on the production of biogenic amines during soy sauce fermentation.

PubMed

Qi, Wei; Hou, Li-Hua; Guo, Hong-Lian; Wang, Chun-Ling; Fan, Zhen-Chuan; Liu, Jin-Fu; Cao, Xiao-Hong

2014-06-01

This study aimed to enhance and improve the quality and safety of soy sauce. In the present work, the change of biogenic amines, such as histamine, tyramine, cadaverine, spermidine, was examined by the treatment of Candida versatilis and Zygosaccharomyces rouxii, and the influence of salt-tolerant yeast on biogenic amines was analysed during the whole fermentation process. The results showed that the content of biogenic amines was elevated after yeast treatment and the content of biogenic amines was influenced by using yeast. The dominating biogenic amine in soy sauce was tyramine. At the end of fermentation, the concentrations of biogenic amines produced by Zygosaccharomyces rouxii and Candida versatilis in the soy mash were 122.71 mg kg(-1) and 69.96 mg kg(-1) . The changes of biogenic amines in high-salt liquid soy mash during fermentation process indicated that a variety of biogenic amines were increased in the fermentation ageing period, which may be due to amino acid decarboxylation to form biogenic amines by yeast decarboxylase. The fermentation period of soy sauce should be longer than 5 months because biogenic amines began to decline after this time period. © 2013 Society of Chemical Industry.

The distribution and adsorption behavior of aliphatic amines in marine and lacustrine sediments

NASA Astrophysics Data System (ADS)

Wang, Xu-chen; Lee, Cindy

1990-10-01

The methylated amines—monomethyl-, dimethyl-, and trimethyl amine (MMA, DMA, TMA)—are commonly found in aquatic environments, apparently as a result of decomposition processes. Adsorption of these amines to clay minerals and organic matter significantly influences their distribution in sediments. Laboratory measurements using 14C-radiolabelled amines and application of a linear partitioning model resulted in calculated adsorption coefficients of 2.4-4.7 (MMA), 3.3 (DMA), and 3.3-4.1 (TMA). Further studies showed that adsorption of amines is influenced by salinity of the porewaters, and clay mineral and organic matter content of the sediment solid phase. Concentrations of monomethyl- and dimethyl amine were measured in the porewaters and the solid phase of sediment samples collected from Flax Pond and Lake Ronkonkoma (NY), Long Island Sound, and the coastal Peru upwelling area. These two amines were present in all sediments investigated. A clear seasonal increase in the solid-phase concentration of MMA and DMA in Flax Pond sediments was likely related to the annual senescence of salt marsh grasses, either directly as a source of these compounds or indirectly by providing additional exchange capacity to the sediments. The distribution of amines in the solid and dissolved phases observed in all sediments investigated suggests that the distribution of these compounds results from a balance among production, decomposition, and adsorption processes.

Esterification of fermentation-derived acids via pervaporation

DOEpatents

Datta, R.; Tsai, S.P.

1998-03-03

A low temperature method for esterifying ammonium- and amine-containing salts is provided whereby the salt is reacted with an alcohol in the presence of heat and a catalyst and then subjected to a dehydration and deamination process using pervaporation. The invention also provides for a method for producing esters of fermentation derived, organic acid salt comprising first cleaving the salt into its cationic part and anionic part, mixing the anionic part with an alcohol to create a mixture; heating the mixture in the presence of a catalyst to create an ester; dehydrating the now heated mixture; and separating the ester from the now-dehydrated mixture. 2 figs.

Esterification of fermentation-derived acids via pervaporation

DOEpatents

Datta, Rathin; Tsai, Shih-Perng

1998-01-01

A low temperature method for esterifying ammonium- and amine-containing salts is provided whereby the salt is reacted with an alcohol in the presence of heat and a catalyst and then subjected to a dehydration and deamination process using pervaporation. The invention also provides for a method for producing esters of fermentation derived, organic acid salt comprising first cleaving the salt into its cationic part and anionic part, mixing the anionic part with an alcohol to create a mixture; heating the mixture in the presence of a catalyst to create an ester; dehydrating the now heated mixture; and separating the ester from the now-dehydrated mixture.

Salting-out assisted liquid-liquid extraction for the determination of biogenic amines in fruit juices and alcoholic beverages after derivatization with 1-naphthylisothiocyanate and high performance liquid chromatography.

PubMed

Jain, Archana; Gupta, Manju; Verma, Krishna K

2015-11-27

A new method for determining biogenic amines in fruit juices and alcoholic beverages is described involving reaction of biogenic amines with 1-naphthylisothiocyanate followed by extraction of 1-naphthylthiourea derivatives with water-miscible organic solvent acetonitrile when solvents phase separation occurred using ammonium sulphate, a process called salting-out assisted liquid-liquid extraction. The extract was analyzed by high-performance liquid chromatography with UV detection at 254nm. The new reagent avoided many of the inconveniences as observed with existing derivatizing agents, such as dansyl chloride and benzoyl chloride, in regard to their inselectivity, instability, adverse effect of excess reagent, and necessity to remove excess reagent. The procedure has been optimized with respect to reaction time and temperature, water-miscible extraction solvent, and salt for solvents phase separation. Use of reagent as dispersed phase in aqueous medium produced derivatives in high yield. A linear calibration was obtained between the amount of biogenic amines in range 1-1000μgL(-1) and peak areas of corresponding thioureas formed; the correlation coefficient was 0.9965, and the limit of detection and limit of quantification found were 1.1μgL(-1) and 3.2μgL(-1), respectively. The pre-concentration method gave an average enrichment factor of 94. The application of the method has been demonstrated in the determination of biogenic amines in commercial samples of fruit juices and alcoholic beverages. In spiking experiments to real samples, the average recovery found by the present method was 94.5% that agreed well with 95.8% obtained by established comparison methods. Copyright © 2015 Elsevier B.V. All rights reserved.

Strong cation exchange-type chiral stationary phase for enantioseparation of chiral amines in subcritical fluid chromatography.

PubMed

Wolrab, Denise; Kohout, Michal; Boras, Mario; Lindner, Wolfgang

2013-05-10

A new strong cation exchange type chiral stationary phase (SCX CSP) based on a syringic acid amide derivative of trans-(R, R)-2-aminocyclohexanesulfonic acid was applied to subcritical fluid chromatography (SFC) for separation of various chiral basic drugs and their analogues. Mobile phase systems consisting of aliphatic alcohols as polar modifiers and a broad range of amines with different substitution patterns and lipophilicity were employed to evaluate the impact on the SFC retention and selectivity characteristics. The observed results point to the existence of carbonic and carbamic acid salts formed as a consequence of reactions occurring between carbon dioxide, the alcoholic modifiers and the amine species present in the sub/supercritical fluid medium, respectively. Evidence is provided that these species are essential for affecting ion exchange between the strongly acidic chiral selector units and the basic analytes, following the well-established stoichiometric displacement mechanisms. Specific trends were observed when different types of amines were used as basic additives. While ammonia gave rise to the formation of the most strongly eluting carbonic and carbamic salt species, simple tertiary amines consistently provided superior levels of enantioselectivity. Furthermore, trends in the chiral SFC separation characteristics were investigated by the systematic variation of the modifier content and temperature. Different effects of additives are interpreted in terms of changes in the relative concentration of the transient ionic species contributing to analyte elution, with ammonia-derived carbamic salts being depleted at elevated temperatures by decomposition. Additionally, in an effort to optimize SFC enantiomer separation conditions for selected analytes, the impact of the type of the organic modifier, temperature, flow rate and active back pressure were also investigated. Copyright © 2013 Elsevier B.V. All rights reserved.

77 FR 48976 - Certain New Chemicals; Receipt and Status Information

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-15

... surface active agent. fluorinated alcohol, reaction products with phosphorus oxide (P205), amine salts. P.... fluorinated alcohol, reaction products with phosphorus oxide (P205), amine salts. P-12-0452...... 07/09/2012...

Method of preparation of a CO.sub.2 removal sorbent with high chemical stability during multiple cycles

DOEpatents

Siriwardane, Ranjani V.; Rosencwaig, Shira

2015-07-14

Method for the production of a clay-alkali-amine CO.sub.2 sorbent prepared by integrating a clay substrate, basic alkali salt, and amine liquid. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay substrate and basic alkali salt may be combined in a solid-solid heterogeneous mixture and followed by introduction of the amine liquid. Alternatively, an alkaline solution may be blended with the amine solution prior to contacting the clay substrate. The clay-alkali-amine CO.sub.2 sorbent is particularly advantageous for low temperature CO.sub.2 removal cycles in a gas stream having a CO.sub.2 concentration less than around 2000 ppm and an oxygen concentration around 21%, such as air. Results are presented illustrating the performance of the clay-alkali-amine CO.sub.2 sorbent compared to a clay-amine sorbent lacking the alkali inclusion.

Diazotisation of Weakly Basic Aromatic and Heterocyclic Amines in Strongly Acid Media

NASA Astrophysics Data System (ADS)

Godovikova, Tamara I.; Rakitin, Oleg A.; Khmel'nitskii, Lenor I.

1983-05-01

The review is devoted to the diazotisation of weakly basic aromatic amines. The methods of synthesis of diazonium salts based on these amines by non-traditional methods are examined. Data on the mechanism of the diazotisation reaction in strongly acid media are surveyed. Reactions of diazonium salts leading to the synthesis of new compounds are presented. The bibliography includes 75 references.

Phase considerations in the gas/particle partitioning of organic amines in the atmosphere

NASA Astrophysics Data System (ADS)

Pankow, James F.

2015-12-01

Amines in the atmosphere are of interest because of their likely role in new particle formation, and because of anthropogenic emissions of amines at post-combustion carbon capture (PCCC) facilities. A conceptual framework for considering the partitioning of a monobasic amine (Am = unprotonated, ;free-base form;) from the gas phase to atmospheric particulate matter (PM) is presented for cases when the PM may be composed of multiple liquid phases. Three types of liquid phases are considered as being individually or simultaneously possible for absorptive uptake of atmospheric amines: w) a mostly water phase; α) a mostly (by mass) organic phase that has at least some polarity (e.g., predominantly secondary organic aerosol (SOA), may contain significant water on a mole fraction basis); and β) a mostly organic phase that is less polar than an α phase (e.g., predominantly primary organic aerosol (POA), containing little water). That one or more salts may contain the aminium ion AmH+ (formed by protonation of Am) is subject to the fact that the trace levels of individual amines in the atmosphere make formation of a pure solid such as AmHHSO4(s) exceedingly unlikely: when solid salts of AmH+ are indeed present, by far the most likely form is as a solid solution, e.g., (NH4+)1-y(AmH+)y HSO4(s)- where y << 1. Neglecting dissolution in solid salts, and considering only partitioning to liquid phases, the overall gas/particle partitioning constant is Kp,tot(m3μg-1) = cp,tot /cg = ∑θfθ Kp,fbθ αfb θ. The quantity cp,tot (μg μg-1) is the total Am concentration (Am + AmH+) in the PM as summed over all phases using the index θ (= w, α, β); cg is the gas-phase concentration of Am; fθ is the mass fraction of the total PM that is the θ phase; Kp,fbθ is the gas/particle partitioning constant for the free-base (Am) form to the θ phase; and 0 < αfbθ < 1 is the fraction of the amine in the θ phase that is in the free-base form. To date, most treatments of the partitioning of amines to PM have only considered contributions to Kp,tot from absorption into a mostly water phase, according to the term fw Kp,fbw/αfbw. However, unless the PM contains little or no organic-phase material, the α and/or β terms are likely to also be relevant. The Am form of a low MW amine will in general have reasonable affinities for both α and β type phases, so in general Kp,fbw, Kp,fbα, and Kp,fbβ will all be roughly similar in magnitude. And, with significant water uptake into an α phase certain to occur at moderate to high RH values, solvation of ions will often be possible in an α phase. This will assist protonation of Am to AmH+ (as is known to occur for nicotine in tobacco smoke PM). The overall result is that to a first approximation, αfbw and αfbα can be similar in magnitude, making Kp,fbα/αfbα likely to be generally comparable to Kp,fbw/αfbw. In a β phase, ion solvation will not be as good, so that for acidic aerosol αfbβ will generally be closer to one than the other two αfb values, making Kp,fbβ/αfbβ smaller than both Kp,fbw/αfbw and Kp,fbα/αfbα. Overall, modeling of amine behavior in the atmosphere should include consideration of partitioning into organic PM. Unfortunately, this will be more difficult than water-phase only modeling because prediction of αfb values in multiphase PM will be greatly complicated by the needs to: 1) have estimated values of acidity constants in mostly organic phases of variable composition; and 2) allow distribution of chemicals over multiple liquid phases.

High Contrast Organic Crystal Optical Modulator for Phased Array Antenna and Optical Signal Processing

DTIC Science & Technology

1994-10-27

Thus, we investigated several other secondary amines for use in the condensation of the picoline salt with various substituted benza!dehydes. C I I...a 10 gallon glass lined reactor was charged with 12 L of methanol, 3.120 kg of picoline , and 6.046 kg of methyl toluene sulfonate. The I reaction...dimethylamino benzaldehyde was added to the newly formed picoline salt, I together with an additional 6 L of methanol. Finally, 500 mL of pyrrolidine were slowly

Nickel-catalyzed amination of aryl chlorides with ammonia or ammonium salts.

PubMed

Green, Rebecca A; Hartwig, John F

2015-03-16

The nickel-catalyzed amination of aryl chlorides to form primary arylamines occurs with ammonia or ammonium sulfate and a well-defined single-component nickel(0) precatalyst containing a Josiphos ligand and an η(2)-bound benzonitrile ligand. This system also catalyzes the coupling of aryl chlorides with gaseous amines in the form of their hydrochloride salts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photoimageable composition

DOEpatents

Simison, Kelby Liv; Dentinger, Paul

2003-11-11

The use of selected buffering amines in a photoimageable composition prevents process bias which with conventional photoresists causes designed features to be distorted, especially in corners and high resolution features. It is believed that the amines react with the catalysts, e.g., photoacids, generated to create an inert salt. The presence of the amines also increases resolution. Suitable photoimageable compositions includes: (a) a multifunctional polymeric epoxy resin that is dissolved in an organic solvent wherein the epoxy resin comprises oligomers of bisphenol A that is quantitatively protected by glycidyl ether and wherein the oligomers have an average functionality that ranges from about 3 to 12; (b) a photoactive compound; and (c) an amine that is selected from the group consisting of triisobutylamine, 1,8-bis(dimethylamino)naphthalene (also known as PROTON SPONGET.TM.), 2,2'-diazabicyclo[2.2.2] octane and mixtures thereof. The photoimageable composition is particularly suited for producing high aspect ratio metal microstructures.

Mesoporous imine-based organic polymer: catalyst-free synthesis in water and application in CO2 conversion.

PubMed

Yu, Xiaoxiao; Yang, Zhenzhen; Guo, Shien; Liu, Zhenghui; Zhang, Hongye; Yu, Bo; Zhao, Yanfei; Liu, Zhimin

2018-06-22

A mesoporous imine-functionalized organic polymer (Imine-POP) was prepared based on the reaction of an aryl ammonium salt with an aromatic aldehyde in water without any catalyst and template. The Pd coordinated Imine-POP exhibited high catalytic activity for the N-formylation of amines with CO2/H2 at 100 °C, affording a series of formamides in high yields.

Syntheses and structure characterization of ten acid-base hybrid crystals based on N-containing aromatic brønsted bases and mineral acids

NASA Astrophysics Data System (ADS)

Lin, Zhihao; Jin, Shouwen; Li, Xiaoliang; Xiao, Xiao; Hu, Kaikai; Guo, Ming; Chi, Xinchen; Liu, Hui; Wang, Daqi

2017-10-01

Cocrystallization of the aromatic brønsted bases with a series of mineral acids gave a total of ten hybrid salts with the compositions: (2-methylquinoline)2: (hydrochloride acid): 3H2O [(HL1)+. (L1)·· (Cl-) · (H2O)3] (1), (6-bromobenzo[d]thiazol-2-amine): (hydrochloride acid) [(HL2)+. (Cl-)] (2), (6-bromobenzo[d]thiazol-2-amine): (nitric acid) [(HL2)+. (NO3-)] (3), (6-bromobenzo[d]thiazol-2-amine): (sulfuric acid) [(HL2)+ · (HSO4)-] (4), (6-bromobenzo[d]thiazol-2-amine): (phosphoric acid) [(HL2)+ · (H2PO4)-] (5), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrochloride acid): 3H2O [(HL3)+ · (Cl-) (H2O)3] (6), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrobromic acid): CH3OH [(HL3)+ · (Br)- · CH3OH] (7), (5,7-dimethyl-1,8-naphthyridine-2-amine): (sulfuric acid): H2O [(HL3)+ · (HSO4)- · H2O] (8), (2-aminophenol): (phosphoric acid) [(HL4)+ · (H2PO4)-] (9), and (2-amino-4-chlorophenol): (phosphoric acid) [(HL5)+ · (H2PO4)-] (10). The ten salts have been characterized by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the ten investigated crystals the ring N of the heterocycle or the NH2 in the aminophenol are protonated when the acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted classical hydrogen bonds between the NH+/NH3+ and deprotonated acidic groups. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O, CHsbnd Cl, CH3sbnd N, CH3sbnd O, CHsbnd Br, CH3sbnd Br, Brsbnd Cl, Clsbnd S, Osbnd S, Osbnd O, Brsbnd S, Hsbnd H, and π-π associations contribute to the stabilization and expansion of the total high-dimensional frameworks. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R22(8), R42(8), R43(10) and R44(12), usually observed in the organic solids, were again shown to be involved in constructing most of these H-bonding networks.

Pyrylium Salts as Reactive Matrices for MALDI-MS Imaging of Biologically Active Primary Amines

NASA Astrophysics Data System (ADS)

Shariatgorji, Mohammadreza; Nilsson, Anna; Källback, Patrik; Karlsson, Oskar; Zhang, Xiaoqun; Svenningsson, Per; Andren, Per E.

2015-06-01

Many neuroactive substances, including endogenous biomolecules, environmental compounds, and pharmaceuticals possess primary amine functional groups. Among these are catecholamine neurotransmitters (e.g., dopamine), many substituted phenethylamines (e.g., amphetamine), as well as amino acids and neuropeptides. In most cases, mass spectrometric (ESI and MALDI) analyses of trace amounts of such compounds are challenging because of their poor ionization properties. We present a method for chemical derivatization of primary amines by reaction with pyrylium salts that facilitates their detection by MALDI-MS and enables the imaging of primary amines in brain tissue sections. A screen of pyrylium salts revealed that the 2,4-diphenyl-pyranylium ion efficiently derivatizes primary amines and can be used as a reactive MALDI-MS matrix that induces both derivatization and desorption. MALDI-MS imaging with such matrix was used to map the localization of dopamine and amphetamine in brain tissue sections and to quantitatively map the distribution of the neurotoxin β- N-methylamino-L-alanine.

Azidoimidazolinium Salts: Safe and Efficient Diazo-transfer Reagents and Unique Azido-donors.

PubMed

Kitamura, Mitsuru

2017-07-01

2-Azido-1,3-dimethylimidazolinium chloride (ADMC) and its corresponding hexafluorophosphate (ADMP) were found to be efficient diazo-transfer reagents to various organic compounds. ADMC was prepared by the reaction of 2-chloro-1,3-dimethylimidazolinium chloride (DMC) and sodium azide. ADMP was isolated as a crystal having good thermal stability and low explosibility. ADMC and ADMP reacted with 1,3-dicarbonyl compounds under mild basic conditions to give 2-diazo-1,3-dicarbonyl compounds in high yields, which were easily isolated in virtue of the high water solubility of the by-products. ADMP showed high diazo-transfer ability to primary amines even in the absence of metal salt such as Cu(II). Using this diazotization approach, various alkyl/aryl azides were directly obtained from their corresponding primary amines in high yields. Furthermore, naphthols reacted with ADMC to give the corresponding diazonaphthoquinones in good to high yields. In addition, 2-azido-1,3-dimethylimidazolinium salts were employed as azide-transfer and migratory amidation reagents. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 721.1675 - Disulfonic acid rosin amine salt of a benzidine derivative (generic name).

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1675 Disulfonic acid rosin amine salt of a benzidine derivative (generic name). (a) Chemical substance and significant new uses subject to reporting...

40 CFR 721.643 - Ethoxylated alcohol, phosphated, amine salt.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Ethoxylated alcohol, phosphated, amine salt. 721.643 Section 721.643 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.643 Ethoxylated...

Robust and Porous β-Diketiminate-Functionalized Metal–Organic Frameworks for Earth-Abundant-Metal-Catalyzed C–H Amination and Hydrogenation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thacker, Nathan C.; Lin, Zekai; Zhang, Teng

We have designed a strategy for postsynthesis installation of the β-diketiminate (NacNac) functionality in a metal–organic framework (MOF) of UiO-topology. Metalation of the NacNac-MOF (I) with earth-abundant metal salts afforded the desired MOF-supported NacNac-M complexes (M = Fe, Cu, and Co) with coordination environments established by detailed EXAFS studies. The NacNac-Fe-MOF catalyst, I•Fe(Me), efficiently catalyzed the challenging intramolecular sp 3 C–H amination of a series of alkyl azides to afford α-substituted pyrrolidines. The NacNac-Cu-MOF catalyst, I•Cu(THF), was effective in promoting the intermolecular sp 3 C–H amination of cyclohexene using unprotected anilines to provide access to secondary amines in excellent selectivity.more » Finally, the NacNac-Co-MOF catalyst, I•Co(H), was used to catalyze alkene hydrogenation with turnover numbers (TONs) as high as 700 000. All of the NacNac-M-MOF catalysts were more effective than their analogous homogeneous catalysts and could be recycled and reused without a noticeable decrease in yield. The NacNac-MOFs thus provide a novel platform for engineering recyclable earth-abundant-element-based single-site solid catalysts for many important organic transformations.« less

HNO and NO release from a primary amine-based diazeniumdiolate as a function of pH

PubMed Central

Salmon, Debra J.; Torres de Holding, Claudia L.; Thomas, Lynta; Peterson, Kyle V.; Goodman, Gens P.; Saavedra, Joseph E.; Srinivasan, Aloka; Davies, Keith M.; Keefer, Larry K.; Miranda, Katrina M.

2011-01-01

The growing evidence that nitroxyl (HNO) has a rich pharmacological potential that differs from that of nitric oxide (NO) has intensified interest in HNO donors. Recently, the diazeniumdiolate (NONOate) based on isopropylamine (IPA/NO; Na[(CH3)2CHNH(N(O)NO)]) was demonstrated to function under physiological conditions as an organic analogue to the commonly used HNO donor Angeli’s salt (Na2N2O3). The decomposition mechanism of Angeli’s salt is dependent on pH, with transition from an HNO to an NO donor occurring abruptly near pH 3. Here, pH is shown to also affect product formation from IPA/NO. Chemical analysis of HNO and NO production led to refinement of an earlier, quantum mechanically based prediction of the pH-dependent decomposition mechanisms of primary amine NONOates such as IPA/NO. Under basic conditions, the amine proton of IPA/NO is able to initiate decomposition to HNO by tautomerization to the nitroso nitrogen (N2). At lower pH, protonation activates a competing pathway to NO production. At pH 8, the donor properties of IPA/NO and Angeli’s salt are demonstrated to be comparable, suggesting that at or above this pH, IPA/NO is primarily an HNO donor. Below pH 5, NO is the major product, while IPA/NO functions as a dual donor of HNO and NO at intermediate pH. This pH-dependent variability in product formation may prove useful in examination of the chemistry of NO and HNO. Furthermore, primary amine NONOates may serve as a tunable class of nitrogen oxide donor. PMID:21405089

Controlled Zn-mediated grafting of thin layers of bipodal diazonium salt on gold and carbon substrates.

PubMed

Torréns, Mabel; Ortiz, Mayreli; Turner, Anthony P F; Beni, Valerio; O'Sullivan, Ciara K

2015-01-07

A controlled, rapid, and potentiostat-free method has been developed for grafting the diazonium salt (3,5-bis(4-diazophenoxy)benzoic acid tetrafluoroborate (DCOOH)) on gold and carbon substrates, based on a Zn-mediated chemical dediazonation. The highly stable thin layer organic platforms obtained were characterized by cyclic voltammetry, AFM, impedance, XP, and Raman spectroscopies. A dediazonation mechanism based on radical formation is proposed. Finally, DCOOH was proved as a linker to an aminated electroactive probe. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Study of picrate salts with amines

NASA Astrophysics Data System (ADS)

Goel, Nidhi; Singh, Udai P.; Singh, Gurdip; Srivastava, Pratibha

2013-03-01

The reaction of picric acid (2,4,6-trinitrophenol) with amines [urea, cyclohexane-1,2-diamine, 1H-1,2,4-triazole-3,5-diamine, 6-phenyl-1,3.5-triazine-2,4-diamine] yielded the corresponding picrate salts 1-4. Theoretical studies reveal that the hydrogen-bond interaction energy decreases on increasing the steric hindrance in amines. The solid state structure of compounds 1-4 was measured by X-ray techniques and compared to the gas phase optimized geometries (DFT/B3LYP). Thermal stability of these salts has been studied by means of thermogravimetric-differential scanning calorimetry (TG-DSC) while kinetic parameters have been evaluated using models fitting and isoconversional methods. Thermolytic pathways have also been suggested.

40 CFR 721.6140 - Dialkyldithiophosphoric acid, aliphatic amine salt.

Code of Federal Regulations, 2010 CFR

2010-07-01

... methods for protecting against such risk, into an MSDS as described in § 721.72(c) within 90 days from the..., aliphatic amine salt. 721.6140 Section 721.6140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... manner or method of manufacture, import, or processing associated with any use of this substance without...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Happe, J.A.; Morgan, R.J.; Walkup, C.M.

The chemical composition of commercial BF/sub 3/:amine complexes are variable and contain BF/sub 4//sup -/ and BF/sub 3/(OH)/sup -/ salts together with other unidentified highly reactive species. The BF/sub 3/:amine complexes, which are susceptible to hydrolysis, also partially convert to the BF/sub 4//sup -/ salt (i.e. BF/sub 4//sup -/NH/sub 3//sup +/C/sub 2/H/sub 5/) upon heating. This salt formation is accelerated in dimethyl sulfoxide solution and in the presence of the epoxides that are present in commercial prepregs. Commercial C fiber-epoxy prepregs are shown to contain either BF/sub 3/:NH/sub 2/C/sub 2/H/sub 5/ or BF/sub 3/:NHC/sub 5/H/sub 10/ species together with theirmore » BF/sub 4//sup -/ salts and a variety of boron-fluorine or carbon-fluorine prepreg species. Considerable variation in the relative quantities of BF/sub 3/:amine to its BF/sub 4//sup -/ salt was observed from prepreg lot to lot, which will cause variable viscosity-time-temperature prepreg cure profiles. It is concluded that the chemically stable and mobile BF/sub 4//sup -/ salt is the pre-dominant catalytic species, acting as a cationic catalyst for the prepreg cure reactions. During the early stages of cure the BF/sub 3/:amine catalyst converts to the BF/sub 4//sup -/ salt in the presence of epoxides, whereas the BF/sub 3/-prepreg species are susceptible to catalytic deactivation and immobilization.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodshire, Anna L.; Lawler, Michael J.; Zhao, Jun

New-particle formation (NPF) is a significant source of aerosol particles into the atmosphere. However, these particles are initially too small to have climatic importance and must grow, primarily through net uptake of low-volatility species, from diameters  ∼  1 to 30–100 nm in order to potentially impact climate. There are currently uncertainties in the physical and chemical processes associated with the growth of these freshly formed particles that lead to uncertainties in aerosol-climate modeling. Four main pathways for new-particle growth have been identified: condensation of sulfuric-acid vapor (and associated bases when available), condensation of organic vapors, uptake of organic acids through acid–base chemistrymore » in the particle phase, and accretion of organic molecules in the particle phase to create a lower-volatility compound that then contributes to the aerosol mass. The relative importance of each pathway is uncertain and is the focus of this work. The 2013 New Particle Formation Study (NPFS) measurement campaign took place at the DOE Southern Great Plains (SGP) facility in Lamont, Oklahoma, during spring 2013. Measured gas- and particle-phase compositions during these new-particle growth events suggest three distinct growth pathways: (1) growth by primarily organics, (2) growth by primarily sulfuric acid and ammonia, and (3) growth by primarily sulfuric acid and associated bases and organics. To supplement the measurements, we used the particle growth model MABNAG (Model for Acid–Base chemistry in NAnoparticle Growth) to gain further insight into the growth processes on these 3 days at SGP. MABNAG simulates growth from (1) sulfuric-acid condensation (and subsequent salt formation with ammonia or amines), (2) near-irreversible condensation from nonreactive extremely low-volatility organic compounds (ELVOCs), and (3) organic-acid condensation and subsequent salt formation with ammonia or amines. MABNAG is able to corroborate the observed differing growth pathways, while also predicting that ELVOCs contribute more to growth than organic salt formation. However, most MABNAG model simulations tend to underpredict the observed growth rates between 10 and 20 nm in diameter; this underprediction may come from neglecting the contributions to growth from semi-to-low-volatility species or accretion reactions. Our results suggest that in addition to sulfuric acid, ELVOCs are also very important for growth in this rural setting. We discuss the limitations of our study that arise from not accounting for semi- and low-volatility organics, as well as nitrogen-containing species beyond ammonia and amines in the model. Quantitatively understanding the overall budget, evolution, and thermodynamic properties of lower-volatility organics in the atmosphere will be essential for improving global aerosol models.« less

Preparation of sorbent pellets with high integrity for sorption of CO.sub.2 from gas streams

DOEpatents

Siriwardane, Ranjani V.

2016-05-10

Method for the production of a CO.sub.2 sorbent prepared by integrating a clay substrate, basic alkali salt, amine liquid, hydraulic binder, and a liquid binder. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay substrate and basic alkali salt may be combined in a solid-solid heterogeneous mixture and followed by introduction of the amine liquid. Alternatively, an alkaline solution may be blended with the amine solution prior to contacting the clay substrate. The clay-alkali-amine CO.sub.2 sorbent is particularly advantageous for low temperature CO.sub.2 removal cycles in a gas stream having a CO.sub.2 concentration less than around 2000 ppm and an oxygen concentration around 21%, such as air.

Bioassays and field immersion tests: a comparison of the antifouling activity of copper-free poly(methacrylic)-based coatings containing tertiary amines and ammonium salt groups.

PubMed

Bressy, C; Hellio, C; Marechal, J P; Tanguy, B; Margaillan, A

2010-10-01

This paper focuses on the activity spectrum of three dimethylalkyl tertiary amines as potential active molecules and the corresponding ammonium salt-based antifouling (AF) paints. Bioassays (using marine bacteria, microalgae and barnacles) and field tests were combined to assess the AF activity of coatings. Bioassay results demonstrated that the ammonium salt-based paints did not inhibit the growth of microorganisms (except the dimethyldodecylammonium-based coatings) and that the tertiary amines were potent towards bacteria, diatoms, and barnacle larvae at non-toxic concentrations (therapeutic ratio, LC50/EC50, <1). The results from field tests indicated that the ammonium salt-based coatings inhibited the settlement of macrofouling and the dimethylhexadecylammonium-based coatings provided protection against slime in comparison with PVC blank panels. Thus, results from laboratory assays did not fully concur with the AF activity of the paints in the field trial.

Diclofenac Salts. V. Examples of Polymorphism among Diclofenac Salts with Alkyl-hydroxy Amines Studied by DSC and HSM

PubMed Central

Fini, Adamo; Cavallari, Cristina; Ospitali, Francesca

2010-01-01

Nine diclofenac salts prepared with alkyl-hydroxy amines were analyzed for their properties to form polymorphs by DSC and HSM techniques. Thermograms of the forms prepared from water or acetone are different in most cases, suggesting frequent examples of polymorphism among these salts. Polymorph transition can be better highlighted when analysis is carried out by thermo-microscopy, which in most cases made it possible to observe the processes of melting of the metastable form and re-crystallization of the stable one. Solubility values were qualitatively related to the crystal structure of the salts and the molecular structure of the cation. PMID:27721347

Uptake of Alkylamines on Dicarboxylic Acids Relevant to Secondary Organic Aerosol Formation

NASA Astrophysics Data System (ADS)

Marrero-Ortiz, W.; Secrest, J.; Zhang, R.

2017-12-01

Aerosols play a critical role in climate directly by scattering and absorbing solar radiation, and indirectly by functioning as cloud condensation nuclei (CCN); both represent the largest uncertainties in climate predictions. New particle formation contributes significantly to CCN production; however, the mechanisms related to particle nucleation and growth processes are not well understood. Organic acids are atmospherically abundant, and their neutralization by low molecular weight amines may result in the formation of stable low volatility aminium salt products contributing to the growth of secondary organic aerosols and even the alteration of the aerosol properties. The acid-base neutralization of particle phase succinic acid and tartaric acid by low molecular weight aliphatic amines, i.e. methylamine, dimethylamine, and trimethylamine, has been investigated by employing a low-pressure fast flow reactor at 298K with an ion drift - chemical ionization mass spectrometer (ID-CIMS). The heterogeneous uptake is time dependent and influenced by organic acids functionality, alkylamines basicity, and steric effect. The implications of our results to atmospheric nanoparticle growth will be discussed.

Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawson, Matthew L.; Varner, Mychel E.; Perraud, Veronique M.

2014-12-18

Aerosol particles are ubiquitous in the atmosphere and have been shown to impact the Earth’s climate, reduce visibility, and adversely affect human health. Modeling the evolution of aerosol systems requires an understanding of the species and mechanisms involved in particle growth, including the complex interactions between particle- and gas-phase species. Here we report studies of displacement of amines (methylamine, dimethylamine or trimethylamine) in methanesulfonate salt particles by exposure to a different gas-phase amine, using a single particle mass spectrometer, SPLAT II. The variation of the displacement with the nature of the amine suggests that behavior is dependent on water inmore » or on the particles. Small clusters of methanesulfonic acid with amines are used as a model in quantum chemical calculations to identify key structural elements that are expected to influence water uptake, and hence the efficiency of displacement by gas-phase molecules in the aminium salts. Such molecular-level understanding of the processes affecting the ability of gas-phase amines to displace particle-phase aminium species is important for modeling the growth of particles and their impacts in the atmosphere.« less

A one-pot radioiodination of aryl amines via stable diazonium salts: preparation of 125I-imaging agents.

PubMed

Sloan, Nikki L; Luthra, Sajinder K; McRobbie, Graeme; Pimlott, Sally L; Sutherland, Andrew

2017-10-05

An operationally simple, one-pot, two-step tandem procedure that allows the incorporation of radioactive iodine into aryl amines via stable diazonium salts is described. The mild conditions are tolerant of various functional groups and substitution patterns, allowing late-stage, rapid access to a wide range of 125 I-labelled aryl compounds and SPECT radiotracers.

Development of a GC-MS-SPME Method for the Determination of Amines in Meteorites

NASA Astrophysics Data System (ADS)

Hilts, R. W.; Skelhorne, A. W.; Simkus, D.; Herd, C. D. K.

2016-08-01

A GC-MS-SPME analytical method for the direct determination of amines in aqueous solution has been developed. The key step in the procedure is the conversion of the amines into their non-volatile ammonium salts by protonation with HCl.

Multiple new-particle growth pathways observed at the US DOE Southern Great Plains field site

DOE PAGES

Hodshire, Anna L.; Lawler, Michael J.; Zhao, Jun; ...

2016-07-28

New-particle formation (NPF) is a significant source of aerosol particles into the atmosphere. However, these particles are initially too small to have climatic importance and must grow, primarily through net uptake of low-volatility species, from diameters  ∼  1 to 30–100 nm in order to potentially impact climate. There are currently uncertainties in the physical and chemical processes associated with the growth of these freshly formed particles that lead to uncertainties in aerosol-climate modeling. Four main pathways for new-particle growth have been identified: condensation of sulfuric-acid vapor (and associated bases when available), condensation of organic vapors, uptake of organic acids through acid–base chemistrymore » in the particle phase, and accretion of organic molecules in the particle phase to create a lower-volatility compound that then contributes to the aerosol mass. The relative importance of each pathway is uncertain and is the focus of this work. The 2013 New Particle Formation Study (NPFS) measurement campaign took place at the DOE Southern Great Plains (SGP) facility in Lamont, Oklahoma, during spring 2013. Measured gas- and particle-phase compositions during these new-particle growth events suggest three distinct growth pathways: (1) growth by primarily organics, (2) growth by primarily sulfuric acid and ammonia, and (3) growth by primarily sulfuric acid and associated bases and organics. To supplement the measurements, we used the particle growth model MABNAG (Model for Acid–Base chemistry in NAnoparticle Growth) to gain further insight into the growth processes on these 3 days at SGP. MABNAG simulates growth from (1) sulfuric-acid condensation (and subsequent salt formation with ammonia or amines), (2) near-irreversible condensation from nonreactive extremely low-volatility organic compounds (ELVOCs), and (3) organic-acid condensation and subsequent salt formation with ammonia or amines. MABNAG is able to corroborate the observed differing growth pathways, while also predicting that ELVOCs contribute more to growth than organic salt formation. However, most MABNAG model simulations tend to underpredict the observed growth rates between 10 and 20 nm in diameter; this underprediction may come from neglecting the contributions to growth from semi-to-low-volatility species or accretion reactions. Our results suggest that in addition to sulfuric acid, ELVOCs are also very important for growth in this rural setting. We discuss the limitations of our study that arise from not accounting for semi- and low-volatility organics, as well as nitrogen-containing species beyond ammonia and amines in the model. Quantitatively understanding the overall budget, evolution, and thermodynamic properties of lower-volatility organics in the atmosphere will be essential for improving global aerosol models.« less

CO.sub.2 removal sorbent composition with high chemical stability during multiple cycles

DOEpatents

Siriwardane, Ranjani V.; Rosencwaig, Shira

2015-09-22

Disclosed herein is a clay-alkali-amine CO.sub.2 sorbent composition prepared by integrating a clay substrate, basic alkali salt, and amine liquid. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay-alkali-amine C02 sorbent is particularly advantageous for low temperature CO.sub.2 removal cycles in a gas stream having a C02 concentration less than around 2000 ppm and an oxygen concentration around 21%, such as air.

Visible-Light Organic Photocatalysis for Latent Radical-Initiated Polymerization via 2e–/1H+ Transfers: Initiation with Parallels to Photosynthesis

PubMed Central

2015-01-01

We report the latent production of free radicals from energy stored in a redox potential through a 2e–/1H+ transfer process, analogous to energy harvesting in photosynthesis, using visible-light organic photoredox catalysis (photocatalysis) of methylene blue chromophore with a sacrificial sterically hindered amine reductant and an onium salt oxidant. This enables light-initiated free-radical polymerization to continue over extended time intervals (hours) in the dark after brief (seconds) low-intensity illumination and beyond the spatial reach of light by diffusion of the metastable leuco-methylene blue photoproduct. The present organic photoredox catalysis system functions via a 2e–/1H+ shuttle mechanism, as opposed to the 1e– transfer process typical of organometallic-based and conventional organic multicomponent photoinitiator formulations. This prevents immediate formation of open-shell (radical) intermediates from the amine upon light absorption and enables the “storage” of light-energy without spontaneous initiation of the polymerization. Latent energy release and radical production are then controlled by the subsequent light-independent reaction (analogous to the Calvin cycle) between leuco-methylene blue and the onium salt oxidant that is responsible for regeneration of the organic methylene blue photocatalyst. This robust approach for photocatalysis-based energy harvesting and extended release in the dark enables temporally controlled redox initiation of polymer syntheses under low-intensity short exposure conditions and permits visible-light-mediated synthesis of polymers at least 1 order of magnitude thicker than achievable with conventional photoinitiated formulations and irradiation regimes. PMID:24786755

Visible-light organic photocatalysis for latent radical-initiated polymerization via 2e⁻/1H⁺ transfers: initiation with parallels to photosynthesis.

PubMed

Aguirre-Soto, Alan; Lim, Chern-Hooi; Hwang, Albert T; Musgrave, Charles B; Stansbury, Jeffrey W

2014-05-21

We report the latent production of free radicals from energy stored in a redox potential through a 2e(-)/1H(+) transfer process, analogous to energy harvesting in photosynthesis, using visible-light organic photoredox catalysis (photocatalysis) of methylene blue chromophore with a sacrificial sterically hindered amine reductant and an onium salt oxidant. This enables light-initiated free-radical polymerization to continue over extended time intervals (hours) in the dark after brief (seconds) low-intensity illumination and beyond the spatial reach of light by diffusion of the metastable leuco-methylene blue photoproduct. The present organic photoredox catalysis system functions via a 2e(-)/1H(+) shuttle mechanism, as opposed to the 1e(-) transfer process typical of organometallic-based and conventional organic multicomponent photoinitiator formulations. This prevents immediate formation of open-shell (radical) intermediates from the amine upon light absorption and enables the "storage" of light-energy without spontaneous initiation of the polymerization. Latent energy release and radical production are then controlled by the subsequent light-independent reaction (analogous to the Calvin cycle) between leuco-methylene blue and the onium salt oxidant that is responsible for regeneration of the organic methylene blue photocatalyst. This robust approach for photocatalysis-based energy harvesting and extended release in the dark enables temporally controlled redox initiation of polymer syntheses under low-intensity short exposure conditions and permits visible-light-mediated synthesis of polymers at least 1 order of magnitude thicker than achievable with conventional photoinitiated formulations and irradiation regimes.

Effectiveness of 2,4-D and Picloram as Forestry Herbicides

Treesearch

Daniel G. Neary; Parshall B. Bush; Jerry L. Michael; John W. Taylor

1986-01-01

Foresters use 2,4-D, alone or in combination with picloram, as often as any herbcide in the South. An active analog of the plant growth hormone indole acetic acid, 2,4-D is used as a In most forest soils in the South where organic matter, moisture, and temperature are adequate, 2,4-D degrades rapidly. Amine and salt tomulations most commonly used in forestry do not...

A Survey and Evaluation of Chemical Warfare Agent-Decontaminants and Decontamination

DTIC Science & Technology

1984-10-15

0.21 citric acid monohydrate, 0.05% detergent, and 98.251 water) all contain calcium hypochlorite and have been used for decontaminating agents from...water repellent chemicals consist of an aluminum salt of a saturated carboxylic acid (such as format, acetate, palmitate, or stearate) mixed with...been conducted. Sawdust, soil, silicone, coal dust, amine or sulfonic acid -containing polymers, organic and inorganic ion-exchange materials, and metal

Coupling in the absence of tertiary amines.

PubMed

Bodanszky, M; Bednarek, M A; Bodanszky, A

1982-10-01

In order to avoid base catalyzed side reactions during coupling, attempts were made to render superfluous the addition of tertiary amines to the reaction mixture. Weak acids were applied for the removal of acid labile protecting groups. Acetic acid and other carboxylic acids were considered unsuitable for this purpose coupling step. Pentachlorophenol and 2,4-dinitrophenol cleaved the Bpoc, Nps and Trt groups but more practical rates were reached with solutions of 1-hydroxybenzotriazole (HOBt) in trifluoroethanol, in acetic acid, or in a mixture of phenol and p-cresol. In addition to acidolysis, HOBt salts of amino components could also be obtained through hydrogenolysis of the Z group or thiolysis of the Nps group in the presence of HOBt, or by the displacement of acetic acid from acetate salts with HOBt. Acylation of HOBt salts of amino components with symmetrical or mixed anhydrides or with active esters did not require the addition of tertiary amine.

Rapid fixation of methylene chloride by a macrocyclic amine.

PubMed

Lee, Jung-Jae; Stanger, Keith J; Noll, Bruce C; Gonzalez, Carlos; Marquez, Manuel; Smith, Bradley D

2005-03-30

A simple macrocyclic amine is alkylated by methylene chloride to give a quaternary ammonium chloride salt. When methylene chloride is the solvent, the reaction exhibits pseudo-first-order kinetics, and the reaction half-life at 25.0 degrees C is 2.0 min. The reaction half-life for a structurally related, acyclic amine is approximately 50 000 times longer. Detailed calculations favor a mechanism where the methylene chloride associates with the macrocycle to form an activated prereaction complex. The macrocyclic nitrogen subsequently attacks the methylene chloride with a classic SN2 trajectory, and although the carbon-chlorine bond breaks, the chloride leaving group does not separate from the newly formed cationic macrocycle, such that the product is a tightly associated ion-pair. X-ray crystal structures of the starting amine and the product salt, as well as kinetic data, support this mechanism.

Metal and alloy nanoparticles by amine-borane reduction of metal salts by solid-phase synthesis: atom economy and green process.

PubMed

Sanyal, Udishnu; Jagirdar, Balaji R

2012-12-03

A new solid state synthetic route has been developed toward metal and bimetallic alloy nanoparticles from metal salts employing amine-boranes as the reducing agent. During the reduction, amine-borane plays a dual role: acts as a reducing agent and reduces the metal salts to their elemental form and simultaneously generates a stabilizing agent in situ which controls the growth of the particles and stabilizes them in the nanosize regime. Employing different amine-boranes with differing reducing ability (ammonia borane (AB), dimethylamine borane (DMAB), and triethylamine borane (TMAB)) was found to have a profound effect on the particle size and the size distribution. Usage of AB as the reducing agent provided the smallest possible size with best size distribution. Employment of TMAB also afforded similar results; however, when DMAB was used as the reducing agent it resulted in larger sized nanoparticles that are polydisperse too. In the AB mediated reduction, BNH(x) polymer generated in situ acts as a capping agent whereas, the complexing amine of the other amine-boranes (DMAB and TMAB) play the same role. Employing the solid state route described herein, monometallic Au, Ag, Cu, Pd, and Ir and bimetallic CuAg and CuAu alloy nanoparticles of <10 nm were successfully prepared. Nucleation and growth processes that control the size and the size distribution of the resulting nanoparticles have been elucidated in these systems.

Reduction of Biogenic Amines during Miso Fermentation by Lactobacillus plantarum as a Starter Culture.

PubMed

Lee, Yi-Chen; Kung, Hsien-Feng; Huang, Ya-Ling; Wu, Chien-Hui; Huang, Yu-Ru; Tsai, Yung-Hsiang

2016-09-01

Lactobacillus plantarum D-103 isolated from a miso product that possesses amine-degrading activity was used as a starter culture in miso fermentation (25°C for 120 days) in this study. The salt content in control samples (without starter culture) and inoculated samples (inoculated with L. plantarum D-103) remained constant at 10.4% of the original salt concentration throughout fermentation, whereas the pH value decreased from 6.2 to 4.6 during fermentation. The inoculated samples had significantly lower (P < 0.05) levels of total volatile basic nitrogen than control samples after 40 days of fermentation. After 120 days of fermentation, the histamine and overall biogenic amine contents in inoculated samples were reduced by 58 and 27%, respectively, compared with control samples. To our knowledge, this is the first report to demonstrate that application of a starter culture with amine-degrading activity in miso products was effective in reducing the accumulation of biogenic amines.

THE EFFECT OF ALKYL AMINE TYPE ON THE EXTRACTION OF NITRIC ACID AND NITROSYLRUTHENIUM NITRATO COMPLEXES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Timmins, T.H.; Mason, E.A.

1963-04-01

An investigation of the solvent extraction characteristics of nitric acid and the nitrato complexes of nitrosylruthenium was conducted, using alkyl amines as extractants. The alkyl amines used were a primary amine Primene JMT, a tertiary amine trilaurylamine (TLA), and a quaternary amine Aliquat 336. The organic phase concentrations of HNO/sub 3/ resulting during extraction by alkyl amines were found to correlate well on the basis of the undissociated aqueous HNO/ sub 3/ activity for both salted (NaNO/sub 3/) and unsalted aqueous phases. The distribution ratios for Ru extraction showed better correlation on this basis than on the basis of aqueousmore » phase nitrate and nitric acid. The order of decreasing Ru extraction at low HNO/sub 3/ concentration (2N) was found to be Aliquat 336, TLA, and Primene JMT. At high HNO/sub 3/ concentration (9N). Primene JMT had the highest Ru extractability. Hapid dilution experiments were utilized to determine the number and aqueous phase concentrations of the extractable species of Ru, and the amine partition coefficients for the species. It was found that two Ru species are extractable, and the more extractable species is present in the aqueous phase at lower concentration than the less extractable species. The mole fractions of both species were found to increase with increasing HNO/sub 3/ concentration. The TLA partition coefficients for the extractable species were found to decrease with increasing HNO/sub 3/ concentration. The quaternary amine, Aliquat 336, was found to have partition coefficients an order of magnitude greater than the tertiary amine, TLA. Equations for the mole fractions and TLA partition coefficients in the region of HNO/sub 3/ concentration investigated were developed. (auth)« less

Hydrophobic Modification of Layered Clays and Compatibility for Epoxy Nanocomposites

PubMed Central

Lin, Jiang-Jen; Chan, Ying-Nan; Lan, Yi-Fen

2010-01-01

Recent studies on the intercalation and exfoliation of layered clays with polymeric intercalating agents involving poly(oxypropylene)-amines and the particular uses for epoxy nanocomposites are reviewed. For intercalation, counter-ionic exchange reactions of clays including cationic layered silicates and anionic Al-Mg layered double hydroxide (LDH) with polymeric organic ions afforded organoclays led to spatial interlayer expansion from 12 to 92 Å (X-ray diffraction) as well as hydrophobic property. The inorganic clays of layered structure could be modified by the poly(oxypropylene)amine-salts as the intercalating agents with molecular weights ranging from 230 to 5,000 g/mol. Furthermore, natural montmorillonite (MMT) clay could be exfoliated into thin layer silicate platelets (ca. 1 nm thickness) in one step by using polymeric types of exfoliating agents. Different lateral dimensions of MMT, synthetic fluorinated Mica and LDH clays had been cured into epoxy nanocomposites. The hydrophobic amine-salt modification resulting in high spacing of layered or exfoliation of individual clay platelets is the most important factor for gaining significant improvements of properties. In particular, these modified clays were reported to gain significant improvements such as reduced coefficient of thermal expansion (CTE), enhanced thermal stability, and hardness. The utilization of these layered clays for initiating the epoxy self-polymerization was also reported to have a unique compatibility between clay and organic resin matrix. However, the matrix domain lacks of covalently bonded crosslink and leads to the isolation of powder material. It is generally concluded that the hydrophobic expansion of the clay inter-gallery spacing is the crucial step for enhancing the compatibility and the ultimate preparation of the advanced epoxy materials.

Effect of Ion Binding in Palmitoyl-Oleoyl Phosphatidylserine Monolayers

NASA Astrophysics Data System (ADS)

Eckler, Matthew; Matysiak, Silvina

2013-03-01

Molecular dynamics simulations of palmitoyl-oleoyl phosphatidylserine (POPS) monolayers at the air-water interface were performed with different ionic strengths with the aim of determining the specific organization and dynamics of counterion binding events. Na + ions penetrated the monolayers into both the ester carbonyl and carboxylate regions of the phospholipids. The binding events increase with the addition of salt. Differences in lipid order parameter, headgroup orientation, and prevalence of inter- and intramolecular hydrogen bonding events between the amine group of the lipid and oxygen groups are observed depending on whether the Na + is binding near the carboxylate or ester region of the lipid. The observed changes are explained in terms of the salting-out effect.

Synthesis of substituted pyrazines

DOEpatents

Pagoria, Philip F.; Zhang, Mao Xi

2016-10-04

A method for synthesizing a pyrazine-containing material according to one embodiment includes contacting an iminodiacetonitrile derivative with a base and a reagent selected from a group consisting of hydroxylamine, a hydroxylamine salt, an aliphatic primary amine, a secondary amine, an aryl-substituted alkylamine a heteroaryl-substituted alkyl amine, an alcohol, an alkanolamine and an aryl alcoholamine. Additional methods and several reaction products are presented. ##STR00001##

Amine-selective bioconjugation using arene diazonium salts.

PubMed

Diethelm, Stefan; Schafroth, Michael A; Carreira, Erick M

2014-08-01

A novel bioconjugation strategy is presented that relies on the coupling of diazonium terephthalates with amines in proteins. The diazonium captures the amine while the vicinal ester locks it through cyclization, ensuring no reversibility. The reaction is highly efficient and proceeds under mild conditions and short reaction times. Densely functionalized, complex natural products were directly coupled to proteins using low concentrations of coupling partners.

Metal and base free synthesis of primary amines via ipso amination of organoboronic acids mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA).

PubMed

Chatterjee, Nachiketa; Goswami, Avijit

2015-08-07

A metal and base free synthesis of primary amines has been developed at ambient temperature through ipso amination of diversely functionalized organoboronic acids, employing a combination of [bis(trifluoroacetoxy)iodo]benzene (PIFA)-N-bromosuccinimide (NBS) and methoxyamine hydrochloride as the aminating reagent. The amines were primarily obtained as their trifluoroacetate salts which on subsequent aqueous alkaline work up provided the corresponding free amines. The combination of PIFA-NBS is found to be the mildest choice compared to the commonly used strong bases (e.g. n-BuLi, Cs2CO3) for activating the aminating agent. The reaction is expected to proceed via activation of the aminating reagent followed by B-N 1,2-aryl migration.

Enrichment Mechanism of Semiconducting Single-walled Carbon Nanotubes by Surfactant Amines

PubMed Central

Ju, Sang-Yong; Utz, Marcel; Papadimitrakopoulos, Fotios

2009-01-01

Utilization of single-walled carbon nanotubes (SWNTs) in high-end applications hinges on separating metallic (met-) from semiconducting (sem-) SWNTs. Surfactant amines, like octadecylamine (ODA) have proven instrumental for the selective extraction of sem-SWNTs from tetrahydrofuran (THF) nanotube suspensions. The chemical shift differences along the tail of an asymmetric, diacetylenic surfactant amine were used to probe the molecular dynamics in the presence and absence of nanotubes via NMR. The results suggest that the surfactant amine head is firmly immobilized onto the nanotube surface together with acidic water, while the aliphatic tail progressively gains larger mobility as it gets farther from the SWNT. X-ray and high-resolution TEM studies indicate that the sem-enriched sample is populated mainly by small nanotube bundles containing ca. three SWNTs. Molecular simulations in conjunction with previously determined HNO3/H2SO4 oxidation depths for met- and sem-SWNTs indicate that the strong pinning of the amine surfactants on the sem-enriched SWNTs bundles is a result of a well-ordered arrangement of nitrate/amine salts separated with a monomolecular layer of H2O. Such continuous 2D arrangement of nitrate/amine salts shields the local environment adjacent to sem-enriched SWNTs bundles and maintains an acidic pH that preserves nanotube oxidation (i.e. SWNTn+). This, in turn, results in strong interactions with charge-balancing NO3- counter ions that through their association with neutralized surfactant amines provide effective THF dispersion and consequent sem-enrichment. PMID:19397291

Three cocrystals and a cocrystal salt of pyrimidin-2-amine and glutaric acid.

PubMed

Odiase, Isaac; Nicholson, Catherine E; Ahmad, Ruksanna; Cooper, Jerry; Yufit, Dmitry S; Cooper, Sharon J

2015-04-01

Four new cocrystals of pyrimidin-2-amine and propane-1,3-dicarboxylic (glutaric) acid were crystallized from three different solvents (acetonitrile, methanol and a 50:50 wt% mixture of methanol and chloroform) and their crystal structures determined. Two of the cocrystals, namely pyrimidin-2-amine-glutaric acid (1/1), C4H5N3·C6H8O4, (I) and (II), are polymorphs. The glutaric acid molecule in (I) has a linear conformation, whereas it is twisted in (II). The pyrimidin-2-amine-glutaric acid (2/1) cocrystal, 2C4H5N3·C6H8O4, (III), contains glutaric acid in its linear form. Cocrystal-salt bis(2-aminopyrimidinium) glutarate-glutaric acid (1/2), 2C4H6N3(+)·C6H6O4(2-)·2C6H8O4, (IV), was crystallized from the same solvent as cocrystal (II), supporting the idea of a cocrystal-salt continuum when both the neutral and ionic forms are present in appreciable concentrations in solution. The diversity of the packing motifs in (I)-(IV) is mainly caused by the conformational flexibility of glutaric acid, while the hydrogen-bond patterns show certain similarities in all four structures.

Production of the ammonium salt of 3,5-dinitro-1,2,4-triazole by solvent extraction

DOEpatents

Lee, Kien Y.; Ott, Donald G.

1980-01-01

The ammonium salt of 3,5-dinitro-1,2,4-triazole has utility as a chemical explosive. In accordance with the present invention, it may readily be produced by solvent extraction using high-molecular weight, water-insoluble amines followed by amination with anhydrous ammonia gas. The aqueous reaction mixture produced in the synthesis of the parent compound, 3,5-dinitro-1,2,4-triazole, is quite suitable--and indeed is preferred--for use as the feed material in the process of the invention.

Caprylate Salts Based on Amines as Volatile Corrosion Inhibitors for Metallic Zinc: Theoretical and Experimental Studies.

PubMed

Valente, Marco A G; Teixeira, Deiver A; Azevedo, David L; Feliciano, Gustavo T; Benedetti, Assis V; Fugivara, Cecílio S

2017-01-01

The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor.

Production of the ammonium salt of 3,5-dinitro-1,2,4-triazole by solvent extraction

DOEpatents

Lee, K.Y.; Ott, D.G.

1979-11-07

The ammonium salt of 3,5-dinitro-1,2,4-triazole has utility as a chemical explosive. In accordance with the present invention, it may readily be produced by solvent extraction using high-molecular weight, water-insoluble amines, followed by amination with anhydrous ammonia gas. The aqueous reaction mixture produced in the synthesis of the parent compound, 3,5-dinitro-1,2,4-triazole, is quite suitable - and indeed is preferred - for use as the feed material in the process of the invention.

Salt-Free Strategy for the Insertion of CO2 into C-H Bonds: Catalytic Hydroxymethylation of Alkynes.

PubMed

Wendling, Timo; Risto, Eugen; Krause, Thilo; Gooßen, Lukas J

2018-04-20

A copper(I) catalyst enables the insertion of carbon dioxide into alkyne C-H bonds by using a suitable organic base with which hydrogenation of the resulting carboxylate salt with regeneration of the base becomes thermodynamically feasible. In the presence of catalytic copper(I) chloride/4,7-diphenyl-1,10-phenanthroline, polymer-bound triphenylphosphine, and 2,2,6,6-tetramethylpiperidine as the base, terminal alkynes undergo carboxylation at 15 bar CO 2 and room temperature. After filtration, the ammonium alkynecarboxylate can be hydrogenated to the primary alcohol and water at a rhodium/molybdenum catalyst, regenerating the amine base. This demonstrates the feasibility of a salt-free overall process, in which carbon dioxide serves as a C1 building block in a C-H functionalization. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Amides and Hydrazides from Amine and Hydrazine Hydrochlorides.

ERIC Educational Resources Information Center

Shama, Sami A.; Tran, Thuan L.

1978-01-01

This safe and efficient procedure for the synthesis of N-substituted amides and hydrazides is a modification of the Schotten-Bausmann procedure in which the amine or hydrazide is replaced by the corresponding hydrochloride salt, and the use of alkali is eliminated. (Author/BB)

Preparation of bis-(1(2)H-tetrazol-5-yl)-amine monohydrate

DOEpatents

Naud, Darren L [Los Alamos, NM; Hiskey, Michael A [Los Alamos, NM

2003-05-27

A process of preparing bis-(1(2)H-tetrazol-5-yl)-amine monohydrate is provided including combining a dicyanamide salt, an azide salt and water to form a first reaction mixture, adding a solution of a first strong acid characterized as having a pKa of less than about 1 to said first reaction mixture over a period of time characterized as providing a controlled reaction rate so as to gradually form hydrazoic acid without loss of significant quantities of hydrazoic acid from the solution while heating the first reaction mixture at temperatures greater than about 65.degree. C., heating the resultant reaction mixture at temperatures greater than about 65.degree. C. for a period of time sufficient to substantially completely form a reaction product, treating the reaction product with a solution of a second strong acid to form a product of bis-(1(2)H-tetrazol-5-yl)-amine monohydrate, and, recovering the bis-(1(2)H-tetrazol-5-yl)-amine monohydrate product.

40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted phenyl...

Cationic electrodepositable coating composition comprising lignin

DOEpatents

Fenn, David; Bowman, Mark P; Zawacky, Steven R; Van Buskirk, Ellor J; Kamarchik, Peter

2013-07-30

A cationic electrodepositable coating composition is disclosed. The present invention in directed to a cationic electrodepositable coating composition comprising a lignin-containing cationic salt resin, that comprises (A) the reaction product of: lignin, an amine, and a carbonyl compound; (B) the reaction product of lignin, epichlorohydrin, and an amine; or (C) combinations thereof.

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow...

Caprylate Salts Based on Amines as Volatile Corrosion Inhibitors for Metallic Zinc: Theoretical and Experimental Studies

PubMed Central

Valente, Marco A. G.; Teixeira, Deiver A.; Azevedo, David L.; Feliciano, Gustavo T.; Benedetti, Assis V.; Fugivara, Cecílio S.

2017-01-01

The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor. PMID:28620602

Simple Copper Catalysts for the Aerobic Oxidation of Amines: Selectivity Control by the Counterion.

PubMed

Xu, Boran; Hartigan, Elizabeth M; Feula, Giancarlo; Huang, Zheng; Lumb, Jean-Philip; Arndtsen, Bruce A

2016-12-19

We describe the use of simple copper-salt catalysts in the selective aerobic oxidation of amines to nitriles or imines. These catalysts are marked by their exceptional efficiency, operate at ambient temperature and pressure, and allow the oxidation of amines without expensive ligands or additives. This study highlights the significant role counterions can play in controlling selectivity in catalytic aerobic oxidations. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt (generic). 721.2577 Section 721.2577 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES...

Impact of the counterion on the solubility and physicochemical properties of salts of carboxylic acid drugs.

PubMed

David, S E; Timmins, P; Conway, B R

2012-01-01

Salt formation is a widely used approach to improve the physicochemical and solid state properties of an active pharmaceutical ingredient. In order to better understand the relationships between the active drug, the selected counterion and the resultant salt form, crystalline salts were formed using four different carboxylic acid drugs and a closely related series of amine counterions. Thirty-six related crystalline salts were prepared, characterized and the relationship between solubility and dissolution behaviour and other properties of the salt and the counterion studied. Salts of four model acid drugs, gemfibrozil, flurbiprofen, ibuprofen and etodolac were prepared using the counterions butylamine, hexylamine, octylamine, benzylamine, cyclohexylamine, tert-butylamine, 2-amino-2-methylpropan-1-ol, 2-amino-2-methylpropan-1,3-diol and tris(hydroxymethyl)aminomethane. Salt formation was confirmed, the salts were characterized and their corresponding solubilities determined and rationalized with respect to the counterions' properties. The properties of the salt highly dependent on the nature of the counterion and, although there is considerable variation, some general conclusion can be drawn. For the alkyl amines series, increasing chain length leads to a reduction in solubility across all the acidic drugs studied and a reduction in melting point, thus contradicting simplistic relationships between solubility and melting point. Small, compact counterions consistently produce crystalline salts with high melting point accompanied with a modest improvement in solubility and the nature of hydrogen bonding between the ions has a major impact on the solubility.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Socha, Aaron; Singh, Seema; Simmons, Blake A.

Methods and compositions are provided for synthesizing ionic liquids from lignin derived compounds comprising: contacting a starting material comprising lignin with a depolymerization agent to depolymerize the lignin and form a mixture of aldehyde containing compounds; contacting the mixture of aldehyde containing compounds with an amine under conditions suitable to convert the mixture of aldehyde containing compounds to a mixture of amine containing compounds; and contacting the mixture of amine containing compounds with an acid under conditions suitable to form an ammonium salt, thereby preparing the ionic liquid.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemaire, Paul C.; Oldham, Christopher J.; Parsons, Gregory N., E-mail: gnp@ncsu.edu

Molecular layer deposition (MLD) of “metalcones,” including alucone, zincone, titanicone, and others, involves self-limiting half-reactions between organic and organometallic (or metal-halide) reactants. Studies have typically focused on metal precursors reacting with ethylene glycol or glycerol to form the films' polymeric O-M-O-(CH{sub x}){sub y}-O-M-O repeat units. The authors report new MLD materials that incorporate tertiary amine groups into the organic linkage. Specifically, reacting triethanolamine (TEA) with either trimethylaluminum or titanium tetrachloride produces TEA-alucone (Al-TEA) and TEA-titanicone (Ti-TEA), respectively, and the amine group leads to unique physical and optical properties. Fourier-transform infrared (FTIR) analysis confirms that the films have prominent C-H, C-N,more » and M-O-C peaks, consistent with the expected bond structure. When exposed to vapors, including water, alcohol, or ammonia, the Ti-TEA films changed their visible color within minutes and increased physical thickness by >35%. The Al-TEA showed significantly less response. X-ray photoelectron spectroscopy and FTIR suggest that HCl generated during MLD coordinates to the amine forming a quaternary ammonium salt that readily binds adsorbates via hydrogen bonding. The visible color change is reversible, and ellipsometry confirms that the color change results from vapor absorption. The unique absorptive and color-changing properties of the TEA-metalcone films point to new possible applications for MLD materials in filtration, chemical absorption, and multifunctional chemical separations/sensing device systems.« less

Organic ion association in aqueous phase and ab initio-based force fields: The case of carboxylate/ammonium salts

NASA Astrophysics Data System (ADS)

Houriez, Céline; Vallet, Valérie; Réal, Florent; Meot-Ner Mautner, Michael; Masella, Michel

2017-10-01

We performed molecular dynamics simulations of carboxylate/methylated ammonium ion pairs solvated in bulk water and of carboxylate/methylated ammonium salt solutions at ambient conditions using an ab initio-based polarizable force field whose parameters are assigned to reproduce only high end quantum computations, at the Møller-Plesset second-order perturbation theory/complete basis set limit level, regarding single ions and ion pairs as isolated and micro-hydrated in gas phase. Our results agree with the available experimental results regarding carboxylate/ammonium salt solutions. For instance, our force field approach predicts the percentage of acetate associated with ammonium ions in CH3 COO-/CH3 NH3+ solutions at the 0.2-0.8M concentration scale to range from 14% to 35%, in line with the estimates computed from the experimental ion association constant in liquid water. Moreover our simulations predict the number of water molecules released from the ion first hydration shell to the bulk upon ion association to be about 2.0 ± 0.6 molecules for acetate/protonated amine ion pairs, 3.1 ± 1.5 molecules for the HCOO-/NH4+ pair and 3.3 ± 1.2 molecules for the CH3COO-/(CH3)4N+ pair. For protonated amine-based ion pairs, these values are in line with experiment for alkali/halide pairs solvated in bulk water. All these results demonstrate the promising feature of ab initio-based force fields, i.e., their capacity in accurately modeling chemical systems that cannot be readily investigated using available experimental techniques.

The Preparation and Reaction of Phenyl-Substituted Pyrylium and Pyridinium Salts.

ERIC Educational Resources Information Center

Awartani, Radi; And Others

1986-01-01

Describes this reaction sequence involving reactivity and synthesis of heterocycles: (1) synthesis of 2,4,6-triphenylpyrylium tetrafluoroborate, II; (2) its reaction with nucleophiles; (3) reaction of pyrylium salt II with a primary amine (benzylamine, p-methoxybenzylamine, and furfurylamine) to form the N-substituted-2,4,6-triphenylpyridinium…

40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylated sulfonated diphenyl oxide... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and alkylated...

40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkylated sulfonated diphenyl oxide... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and alkylated...

Stille coupling via C-N bond cleavage

NASA Astrophysics Data System (ADS)

Wang, Dong-Yu; Kawahata, Masatoshi; Yang, Ze-Kun; Miyamoto, Kazunori; Komagawa, Shinsuke; Yamaguchi, Kentaro; Wang, Chao; Uchiyama, Masanobu

2016-09-01

Cross-coupling is a fundamental reaction in the synthesis of functional molecules, and has been widely applied, for example, to phenols, anilines, alcohols, amines and their derivatives. Here we report the Ni-catalysed Stille cross-coupling reaction of quaternary ammonium salts via C-N bond cleavage. Aryl/alkyl-trimethylammonium salts [Ar/R-NMe3]+ react smoothly with arylstannanes in 1:1 molar ratio in the presence of a catalytic amount of commercially available Ni(cod)2 and imidazole ligand together with 3.0 equivalents of CsF, affording the corresponding biaryl with broad functional group compatibility. The reaction pathway, including C-N bond cleavage step, is proposed based on the experimental and computational findings, as well as isolation and single-crystal X-ray diffraction analysis of Ni-containing intermediates. This reaction should be widely applicable for transformation of amines/quaternary ammonium salts into multi-aromatics.

Isotopic analyses of nitrogenous compounds from the Murchison meteorite: ammonia, amines, amino acids, and polar hydrocarbons

NASA Technical Reports Server (NTRS)

Pizzarello, S.; Feng, X.; Epstein, S.; Cronin, J. R.

1994-01-01

The combined volatile bases (ammonia, aliphatic amines, and possibly other bases), ammonia, amino acids, and polar hydrocarbons were prepared from the Murchison meteorite for isotopic analyses. The volatile bases were obtained by cryogenic transfer after acid-hydrolysis of a hot-water extract and analyzed by combined gas chromatography-mass spectrometry of pentafluoropropionyl derivatives. The aliphatic amines present in this preparation comprise a mixture that includes both primary and secondary isomers through C5 at a total concentration of > or = 100 nmoles g-1. As commonly observed for meteoritic organic compounds, almost all isomers through C5 are present, and the concentrations within homologous series decrease with increasing chain length. Ammonia was chromatographically separated from the other volatile bases and found at a concentration of 1.1-1.3 micromoles g-1 meteorite. The ammonia analyzed includes contributions from ammonium salts and the hydrolysis of extractable organic compounds, e.g., carboxamides. Stable isotope analyses showed the volatile bases to be substantially enriched in the heavier isotopes, relative to comparable terrestrial compounds delta D < or = +1221%; delta 13C = +22%; delta 15N = +93%). Ammonia, per se, was found to have a somewhat lower delta 15N value (+69%) than the total volatile bases; consequently, a higher delta 15N (>93%) can be inferred for the other bases, which include the amines. Solvent-extractable polar hydrocarbons obtained separately were found to be enriched in 15N (delta 15N = +104%). Total amino acids, prepared from a hydrolyzed hot-water extract by cation exchange chromatography, gave a delta 15N of +94%, a value in good agreement with that obtained previously. Nitrogen isotopic data are also given for amino acid fractions separated chromatographically. The delta 15N values of the Murchison soluble organic compounds analyzed to date fall within a rather narrow range (delta 15N = +94 +/- 8%), an observation consistent with their formation, or formation of their precursors, by interstellar chemistry.

Micro-CT Imaging of Denatured Chitin by Silver to Explore Honey Bee and Insect Pathologies

PubMed Central

Butzloff, Peter R.

2011-01-01

Background Chitin and cuticle coatings are important to the environmental and immune defense of honey bees and insect pollinators. Pesticides or environmental effects may target the biochemistry of insect chitin and cuticle coating. Denaturing of chitin involves a combination of deacetylation, intercalation, oxidation, Schweiger-peeling, and the formation of amine hydrochloride salt. The term “denatured chitin” calls attention to structural and property changes to the internal membranes and external carapace of organisms so that some properties affecting biological activities are diminished. Methodology/Principal Findings A case study was performed on honey bees using silver staining and microscopic computer-tomographic x-ray radiography (micro-CT). Silver nitrate formed counter-ion complexes with labile ammonium cations and reacted with amine hydrochloride. Silver was concentrated in the peritrophic membrane, on the abdomen, in the glossa, at intersegmental joints (tarsi), at wing attachments, and in tracheal air sacs. Imaged mono-esters and fatty acids from cuticle coating on external surfaces were apparently reduced by an alcohol pretreatment. Conclusions/Significance The technique provides 3-dimensional and sectional images of individual honey bees consistent with the chemistries of silver reaction and complex formation with denatured chitin. Environmental exposures and influences such as gaseous nitric oxide intercalant, trace oxidants such as ozone gas, oligosachharide salt conversion, exposure to acid rain, and chemical or biochemical denaturing by pesticides may be studied using this technique. Peritrophic membranes, which protect against food abrasion, microorganisms, and permit efficient digestion, were imaged. Apparent surface damage to the corneal lenses of compound eyes by dilute acid exposure consistent with chitin amine hydrochloride formation was imaged. The technique can contribute to existing insect pathology research, and may provide an additional tool for research on CCD. PMID:22110654

In vitro and In vivo Antimalarial Activity of Amphiphilic Naphthothiazolium Salts with Amine-Bearing Side Chains

PubMed Central

Ulrich, Peter; Gipson, Gregory R.; Clark, Martha A.; Tripathi, Abhai; Sullivan, David J.; Cerami, Carla

2014-01-01

Because of emerging resistance to existing drugs, new chemical classes of antimalarial drugs are urgently needed. We have rationally designed a library of compounds that were predicted to accumulate in the digestive vacuole and then decrystallize hemozoin by breaking the iron carboxylate bond in hemozoin. We report the synthesis of 16 naphthothiazolium salts with amine-bearing side chains and their activities against the erythrocytic stage of Plasmodium falciparum in vitro. KSWI-855, the compound with the highest efficacy against the asexual stages of P. falciparum in vitro, also had in vitro activity against P. falciparum gametocytes and in vivo activity against P. berghei in a murine malaria model. PMID:25184829

Platinum-Catalyzed, Terminal-Selective C(sp(3))-H Oxidation of Aliphatic Amines.

PubMed

Lee, Melissa; Sanford, Melanie S

2015-10-14

This Communication describes the terminal-selective, Pt-catalyzed C(sp(3))-H oxidation of aliphatic amines without the requirement for directing groups. CuCl2 is employed as a stoichiometric oxidant, and the reactions proceed in high yield at Pt loadings as low as 1 mol%. These transformations are conducted in the presence of sulfuric acid, which reacts with the amine substrates in situ to form ammonium salts. We propose that protonation of the amine serves at least three important roles: (i) it renders the substrates soluble in the aqueous reaction medium; (ii) it limits binding of the amine nitrogen to Pt or Cu; and (iii) it electronically deactivates the C-H bonds proximal to the nitrogen center. We demonstrate that this strategy is effective for the terminal-selective C(sp(3))-H oxidation of a variety of primary, secondary, and tertiary amines.

Platinum-Catalyzed Terminal-Selective C(sp3)–H Oxidation of Aliphatic Amines

PubMed Central

Lee, Melissa; Sanford, Melanie S.

2016-01-01

This paper describes the terminal-selective Pt-catalyzed C(sp3)–H oxidation of aliphatic amines without the requirement for directing groups. CuCl2 is employed as a stoichiometric oxidant, and the reactions proceed in high yield at Pt loadings as low as 1 mol %. These transformations are conducted in the presence of sulfuric acid, which reacts with the amine substrates in situ to form ammonium salts. We propose that protonation of the amine serves at least three important roles: (i) it renders the substrates soluble in the aqueous reaction medium; (ii) it limits binding of the amine nitrogen to Pt or Cu; and (ii) it electronically deactivates the C–H bonds proximal to the nitrogen center. We demonstrate that this strategy is effective for the terminal-selective C(sp3)–H oxidation of a variety of primary, secondary and tertiary amines. PMID:26439251

Water-Free Proton-Conducting Membranes for Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Yen, Shiao-Pin

2007-01-01

Poly-4-vinylpyridinebisulfate (P4VPBS) is a polymeric salt that has shown promise as a water-free proton-conducting material (solid electrolyte) suitable for use in membrane/electrode assemblies in fuel cells. Heretofore, proton-conducting membranes in fuel cells have been made from perfluorinated ionomers that cannot conduct protons in the absence of water and, consequently, cannot function at temperatures >100 C. In addition, the stability of perfluorinated ionomers at temperatures >100 C is questionable. However, the performances of fuel cells of the power systems of which they are parts could be improved if operating temperatures could be raised above 140 C. What is needed to make this possible is a solid-electrolyte material, such as P4VPBS, that can be cast into membranes and that both retains proton conductivity and remains stable in the desired higher operating temperature range. A family of solid-electrolyte materials different from P4VPBS was described in Anhydrous Proton-Conducting Membranes for Fuel Cells (NPO-30493), NASA Tech Briefs, Vol. 29, No. 8 (August 2005), page 48. Those materials notably include polymeric quaternized amine salts. If molecules of such a polymeric salt could be endowed with flexible chain structures, it would be possible to overcome the deficiencies of simple organic amine salts that must melt before being able to conduct protons. However, no polymeric quaternized amine salts have yet shown to be useful in this respect. The present solid electrolyte is made by quaternizing the linear polymer poly- 4-vinylpyridine (P4VP) to obtain P4VPBS. It is important to start with P4VP having a molecular weight of 160,000 daltons because P4VPBS made from lower-molecular-weight P4VP yields brittle membranes. In an experimental synthesis, P4VP was dissolved in methanol and then reacted with an excess of sulfuric acid to precipitate P4VPBS. The precipitate was recovered, washed several times with methanol to remove traces of acid, and dried to a white granular solid. In another synthesis, nanoparticles of silica rich with surface hydroxyl groups were added to P4VP in methanol solution, which was then reacted with excess sulfuric acid to precipitate granules of a composite that most probably had the composition (P4VPBS)-SiO2-SiO(HSO4)2. The granular P4VPBS produced in the first-mentioned synthesis was dissolved in water to make a glue-like, turbid solution; the granular P4VPBS/silica composite produced in the second-mentioned synthesis was mixed with water to make a turbid, glue-like suspension. The proportions of polymer salt to water in such preparations can be varied; it was found that approximately equal parts of water and polymer salt yield a solution or suspension amenable to further processing.

Carbon Dioxide Transformation in Imidazolium Salts: Hydroaminomethylation Catalyzed by Ru-Complexes.

PubMed

Ali, Meher; Gual, Aitor; Ebeling, Gunter; Dupont, Jairton

2016-08-23

The catalytic species generated by dissolving Ru3 (CO)12 in the ionic liquids 1-n-butyl-3-methyl-imidazolium chloride or 1-n-butyl-2,3-dimethyl-imidazolium chloride are efficient multifunctional catalysts for: (a) reverse water-gas shift, (b) hydroformylation of alkenes, and (c) reductive amination of aldehydes. Thus the reaction of alkenes with primary or secondary amines (alkene/amine, 1:1) under CO2 /H2 (1:1) affords the hydroaminomethylations products in high alkene conversions (up to 99 %) and selectivities (up to 96 %). The reaction proceeds under relatively mild reaction conditions (120 °C, 60 bar=6 MPa) and affords selectively secondary and tertiary amines. The presence of amine strongly reduces the alkene hydrogenation competitive pathway usually observed in the hydroformylation of terminal alkenes by Ru complexes. The catalytic system is also highly active for the reductive amination of aldehydes and ketones yielding amines in high yields (>90 %). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Method and system for capturing carbon dioxide and/or sulfur dioxide from gas stream

DOEpatents

Chang, Shih-Ger; Li, Yang; Zhao, Xinglei

2014-07-08

The present invention provides a system for capturing CO.sub.2 and/or SO.sub.2, comprising: (a) a CO.sub.2 and/or SO.sub.2 absorber comprising an amine and/or amino acid salt capable of absorbing the CO.sub.2 and/or SO.sub.2 to produce a CO.sub.2- and/or SO.sub.2-containing solution; (b) an amine regenerator to regenerate the amine and/or amino acid salt; and, when the system captures CO.sub.2, (c) an alkali metal carbonate regenerator comprising an ammonium catalyst capable catalyzing the aqueous alkali metal bicarbonate into the alkali metal carbonate and CO.sub.2 gas. The present invention also provides for a system for capturing SO.sub.2, comprising: (a) a SO.sub.2 absorber comprising aqueous alkali metal carbonate, wherein the alkali metal carbonate is capable of absorbing the SO.sub.2 to produce an alkali metal sulfite/sulfate precipitate and CO.sub.2.

Impregnated metal-polymeric functional beads

NASA Technical Reports Server (NTRS)

Rembaum, Alan (Inventor); Volksen, Willi (Inventor)

1980-01-01

Amine containing polymeric microspheres such as polyvinyl pyridine are complexed with metal salts or acids containing metals such as gold, platinum or iron. After reduction with sodium borohydride, the salt is reduced to finely divided free metal or metal oxides, useful as catalysts. Microspheres containing covalent bonding sites can be used for labeling or separating proteins.

Impregnated metal-polymeric functional beads

NASA Technical Reports Server (NTRS)

Rembaum, Alan (Inventor); Volksen, Willi (Inventor)

1978-01-01

Amine containing polymeric microspheres such as polyvinyl pyridine are complexed with metal salts or acids containing metals such as gold, platinum or iron. After reduction with sodium borohydride, the salt is reduced to finely divided free metal or metal oxides, useful as catalysts. Microspheres containing covalent bonding sites can be used for labeling or separating proteins.

Reactions of Solvated Ions Final Report

DOE R&D Accomplishments Database

Taube, H.

1962-09-24

Brief summaries are presented on isotopic dilution studies on salts dissolved in CH{sub 3}OH, studies on metal and metal salts in solvents of the amine type, and studies on phosphato complexes of the pentammine Co(III) series. A list of papers published on reactions of solvated ions is included. (N.W.R.)

Photoaddition of N-substituted piperazines to C60: an efficient approach to the synthesis of water-soluble fullerene derivatives.

PubMed

Troshina, Olesya A; Troshin, Pavel A; Peregudov, Alexander S; Kozlovski, Viacheslav I; Lyubovskaya, Rimma N

2006-07-17

An oxidative radical photoaddition of mono N-substituted piperazines to [60]fullerene was systematically investigated. Reactions of C60 with piperazines bearing bulky electron-withdrawing groups (2-pyridyl, 2-pyrimidinyl) were found to be the most selective and yielded C60(amine)4O as major products along with small amounts of C60(amine)2. In contrast, interactions of fullerene with N-methylpiperazine and N-(tert-butoxycarbonyl)piperazine were found to have low selectivity due to different side reactions. Tetraaminofullerene derivative C60(N-(2-pyridyl)piperazine)4O was found to react readily with organic and inorganic acids to yield highly water-soluble salts (solubility approximately 150 mg mL(-1)). In contrast, C60(N-(2-pyrimidinyl)piperazine)4O undergoes hydrolysis under the same conditions and results in a complex mixture of compounds with an average composition of C60(N-(2-pyrimidinyl)piperazine)2(OH)2O. Radical photoaddition of N-(2-pyridyl)piperazine to fullerene derivatives can be used as a facile route for their transformation into water-soluble compounds. Two model fullerene cycloadducts (a methanofullerene and a pyrrolidinofullerene) were easily converted into mixtures of regioisomers of A=C60(N-(2-pyridyl)piperazine)4O (A=cyclic addend) that give highly water-soluble salts under acid treatment.

New water-soluble metal working fluids additives from phosphonic acid derivatives for aluminum alloy materials.

PubMed

Kohara, Ichitaro; Tomoda, Hideyuki; Watanabe, Shoji

2007-01-01

Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short paper describes properties of new additives for water-soluble cutting fluids for aluminum alloy materials. Some alkyldiphosphonic acids were prepared with known method. Amine salts of these phosphonic acids showed anti-corrosion property for aluminum alloy materials. However, they have no hard water tolerance. Monoesters of octylphosphonic acid were prepared by the reaction of octylphosphonic acid dichloride with various alcohols in the presence of triethylamine. Amine salts of monoester of octylphosphonic acid with diethyleneglycol monomethyl ether, ethyleneglycol monomethyl ether and triethyleneglycol monomethyl ether showed both of a good anti-corrosion property for aluminum alloy materials and hard water tolerance.

In vitro and in vivo antimalarial activity of amphiphilic naphthothiazolium salts with amine-bearing side chains.

PubMed

Ulrich, Peter; Gipson, Gregory R; Clark, Martha A; Tripathi, Abhai; Sullivan, David J; Cerami, Carla

2014-10-01

Because of emerging resistance to existing drugs, new chemical classes of antimalarial drugs are urgently needed. We have rationally designed a library of compounds that were predicted to accumulate in the digestive vacuole and then decrystallize hemozoin by breaking the iron carboxylate bond in hemozoin. We report the synthesis of 16 naphthothiazolium salts with amine-bearing side chains and their activities against the erythrocytic stage of Plasmodium falciparum in vitro. KSWI-855, the compound with the highest efficacy against the asexual stages of P. falciparum in vitro, also had in vitro activity against P. falciparum gametocytes and in vivo activity against P. berghei in a murine malaria model. © The American Society of Tropical Medicine and Hygiene.

Arynes, diaryliodonium salts and azine N-oxides in transition metal-free electrophilic N-arylation

NASA Astrophysics Data System (ADS)

Bugaenko, D. I.; Karchava, A. V.; Yurovskaya, M. A.

2018-03-01

The main approach to the synthesis of aromatic and heteroaromatic amines is based on palladium- and copper-catalyzed N-arylation reactions. Although these methods are highly efficient and provide extensive opportunities for the synthesis of (het)arylamines with various structures and properties, they have some limitations related to the catalysts used and reaction conditions. This review addresses alternative approaches to N-(het)arylation that have been extensively developed in the past decade and are based on the use of arynes, diaryliodonium salts and azine N-oxides as electrophilic (het)arylating agents. Because of mild reaction conditions and no need for catalysts and strong bases, these N-(het)arylation methods are attractive for various synthetic applications and open up new possibilities for the preparation of valuable organic compounds inaccessible via traditional catalytic methods. The attention is focussed on publications of the last decade. The bibliography includes 112 references.

Catalytic thermometric titrations in non-aqueous solvents by coulometrically generated titrant.

PubMed

Vajgand, V J; Gaál, F F; Brusin, S S

1970-05-01

Catalytic thermometric titrations have been developed for tertiary amines and salts of organic acids in acetic and propionic anhydride with titrant coulometrically generated at a mercury and/or platinum anode, hydroquinone being added to the solution titrated if the platinum anode is used. The results obtained are compared with those obtained by coulometric titration with the end-point detected either photometrically or potentiometrically. On a élaboré des titrages thermométriques catalytiques pour les amines tertiaires et les sels d'acides organiques en anhydrides aétique et propionique avec l'agent de titrage engendré coulométriquement sur une anode de mercure et/ou platine, de l'hydroquinone étant ajoutée à la solution titrée si l'on emploie l'anode de platine. Les résultats obtenus sont comparés avec ceux obtenus par titrage coulométrique avec le point de fin de réaction détecté soit photométriquement soit potentioétriquement.

Higher value films prepared from poly(vinyl alcohol) and amylose-fatty acid derivatives inclusion complexes

USDA-ARS?s Scientific Manuscript database

Water soluble amylose fatty acid and fatty ammonium salt inclusion complexes (AIC) were prepared by jet cooked high amylose corn starch with water soluble salts of long chain fatty acids or fatty amines. The formation of AIC was confirmed by X-ray diffraction of freeze-dried samples. After dissoluti...

Amine Enrichment of Thin-Film Composite Membranes via Low Pressure Plasma Polymerization for Antimicrobial Adhesion.

PubMed

Reis, Rackel; Dumée, Ludovic F; He, Li; She, Fenghua; Orbell, John D; Winther-Jensen, Bjorn; Duke, Mikel C

2015-07-15

Thin-film composite membranes, primarily based on poly(amide) (PA) semipermeable materials, are nowadays the dominant technology used in pressure driven water desalination systems. Despite offering superior water permeation and salt selectivity, their surface properties, such as their charge and roughness, cannot be extensively tuned due to the intrinsic fabrication process of the membranes by interfacial polymerization. The alteration of these properties would lead to a better control of the materials surface zeta potential, which is critical to finely tune selectivity and enhance the membrane materials stability when exposed to complex industrial waste streams. Low pressure plasma was employed to introduce amine functionalities onto the PA surface of commercially available thin-film composite (TFC) membranes. Morphological changes after plasma polymerization were analyzed by SEM and AFM, and average surface roughness decreased by 29%. Amine enrichment provided isoelectric point changes from pH 3.7 to 5.2 for 5 to 15 min of plasma polymerization time. Synchrotron FTIR mappings of the amine-modified surface indicated the addition of a discrete 60 nm film to the PA layer. Furthermore, metal affinity was confirmed by the enhanced binding of silver to the modified surface, supported by an increased antimicrobial functionality with demonstrable elimination of E. coli growth. Essential salt rejection was shown minimally compromised for faster polymerization processes. Plasma polymerization is therefore a viable route to producing functional amine enriched thin-film composite PA membrane surfaces.

Preparation of nanoporous metal foam from high nitrogen transition metal complexes

DOEpatents

Tappan, Bryce C.; Huynh, My Hang V.; Hiskey, Michael A.; Son, Steven F.; Oschwald, David M.; Chavez, David E.; Naud, Darren L.

2006-11-28

Nanoporous metal foams are prepared by ignition of high nitrogen transition metal complexes. The ammonium salts of iron(III) tris[bi(tetrazolato)-amine], cobalt(III) tris(bi(tetrazolato)amine), and high nitrogen compounds of copper and silver were prepared as loose powders, pressed into pellets and wafers, and ignited under an inert atmosphere to form nanoporous metal foam monoliths having very high surface area and very low density.

Enantioselective α-Vinylation of Aldehydes Via the Synergistic Combination of Copper and Amine Catalysis

PubMed Central

Skucas, Eduardas; MacMillan, David W. C.

2012-01-01

The enantioselective α-vinylation of aldehydes using vinyl iodonium triflate salts has been accomplished via the synergistic combination of copper and chiral amine catalysis. These mild catalytic conditions provide a direct route for the enantioselective construction of enolizable α-formyl vinylic stereocenters without racemization or olefin transposition. These high-value coupling adducts are readily converted into a variety of useful olefin synthons. PMID:22616631

Initial solubility & density evaluation of Non-Aqueous system of amino acid salts for CO2 capture: potassium prolinate blended with ethanol and ethylene glycol

NASA Astrophysics Data System (ADS)

Murshid, Ghulam; Garg, Sahil

2018-05-01

Amine scrubbing is the state of the art technology for CO2 capture, and solvent selection can significantly reduce the capital and energy cost of the process. Higher energy requirement for aqueous amine based CO2 removal process is still a most important downside preventive its industrial deployment. Therefore, in this study, novel non-aqueous based amino acid salt system consisting of potassium prolinate, ethanol and ethylene glycol has been studied. This work presents initial CO2 solubility study and important physical properties i.e. density of the studied solvent system. Previous work showed that non-aqueous system of potassium prolinate and ethanol has good absorption rates and requires lower energy for solvent regeneration. However, during regeneration, solvent loss issues were found due to lower boiling point of the ethanol. Therefore, ethylene glycol was added into current studied system for enhancing the overall boiling point of the system. The good initial CO2 solubility and low density of studied solvent system offers several advantages as compared to conventional amine solutions.

Synthesis, Evaluation, and Formulation Studies on New Oxidizers as Alternatives to Ammonium Perchlorate in DoD Missile Propulsion Applications

DTIC Science & Technology

2007-04-23

7 oxamide (4)..................................................................................13 Figure 5—5. Direct Nitration Efforts...5—8. Acylations of FOX-7 Potassium Salt. ............................................................16 Figure 5—9. Nitration of FOX-7 Salts...Dinitramide ADNA – Ammonium di(nitramido) amine ADNDNE – diammonium di(nitramido) dinitoethylene AN – Ammonium Nitrate AP – Ammonium Perchlorate ATK

Layer-by-Layer Templated Assembly of Silica at the Nanoscale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinestrosa, Juan Pablo; Sutton, Jonathan E.; Allison, David P.

2013-01-29

Bioinspired bottom-up assembly and layer-by-layer (LbL) construction of inorganic materials from lithographically defined organic templates enables the fabrication of nanostructured systems under mild temperature and pH conditions. Such processes open the door to low-impact manufacturing and facile recycling of hybrid materials for energy, biology, and information technologies. Here, templated LbL assembly of silica was achieved using a combination of electron beam lithography, chemical lift-off, and aqueous solution chemistry. Nanopatterns of lines, honeycomb-lattices, and dot arrays were defined in polymer resist using electron beam lithography. Following development, exposed areas of silicon were functionalized with a vapor deposited amine-silane monolayer. Silicic acidmore » solutions of varying pH and salt content were reacted with the patterned organic amine-functional templates. Vapor treatment and solution reaction could be repeated, allowing LbL deposition. Conditions for the silicic acid deposition had a strong effect on thickness of each layer, and the morphology of the amorphous silica formed. Defects in the arrays of silica nanostructures were minor and do not affect the overall organization of the layers. In conclusion, the bioinspired method described here facilitates the bottom-up assembly of inorganic nanostructures defined in three dimensions and provides a path, via LbL processing, for the construction of layered hybrid materials under mild conditions.« less

[The UV-Vis spectra and substituent effect of organoimido derivatives of polyoxometalates].

PubMed

Li, Qiang; Wei, Yong-ge; Wang, Yuan; Guo, Hong-you

2005-06-01

In the presence of a carbodiimine, i.e. DCC, a series of organoimido derivatives of polyoxometalates have been synthesized via the reaction of [alpha-Mo8O26]4- with aromatic amines and its hydrochloride salt. Elemental analysis, IR, 1H-NMR and UV-Vis spectra were used to characterize those hybrids, in particular their UV-Vis spectra have been studied. The results show that typical metal-ligand charge transfer (MLCT) transitions occur in the organic-inorganic hybrid molecules. There is a good linear relationship between the shift of UV-Vis absorptions (delta lamda max) and conjugation effect of the p-substituted group (sigmaR).

Chemoselective single-site Earth-abundant metal catalysts at metal–organic framework nodes

PubMed Central

Manna, Kuntal; Ji, Pengfei; Lin, Zekai; Greene, Francis X.; Urban, Ania; Thacker, Nathan C.; Lin, Wenbin

2016-01-01

Earth-abundant metal catalysts are critically needed for sustainable chemical synthesis. Here we report a simple, cheap and effective strategy of producing novel earth-abundant metal catalysts at metal–organic framework (MOF) nodes for broad-scope organic transformations. The straightforward metalation of MOF secondary building units (SBUs) with cobalt and iron salts affords highly active and reusable single-site solid catalysts for a range of organic reactions, including chemoselective borylation, silylation and amination of benzylic C–H bonds, as well as hydrogenation and hydroboration of alkenes and ketones. Our structural, spectroscopic and kinetic studies suggest that chemoselective organic transformations occur on site-isolated, electron-deficient and coordinatively unsaturated metal centres at the SBUs via σ-bond metathesis pathways and as a result of the steric environment around the catalytic site. MOFs thus provide a novel platform for the development of highly active and affordable base metal catalysts for the sustainable synthesis of fine chemicals. PMID:27574182

Chemoselective single-site Earth-abundant metal catalysts at metal–organic framework nodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manna, Kuntal; Ji, Pengfei; Lin, Zekai

2016-08-30

Earth-abundant metal catalysts are critically needed for sustainable chemical synthesis. Here we report a simple, cheap and effective strategy of producing novel earth-abundant metal catalysts at metal–organic framework (MOF) nodes for broad-scope organic transformations. The straightforward metalation of MOF secondary building units (SBUs) with cobalt and iron salts affords highly active and reusable single-site solid catalysts for a range of organic reactions, including chemoselective borylation, silylation and amination of benzylic C–H bonds, as well as hydrogenation and hydroboration of alkenes and ketones. Our structural, spectroscopic and kinetic studies suggest that chemoselective organic transformations occur on site-isolated, electron-deficient and coordinatively unsaturatedmore » metal centres at the SBUs via σ-bond metathesis pathways and as a result of the steric environment around the catalytic site. MOFs thus provide a novel platform for the development of highly active and affordable base metal catalysts for the sustainable synthesis of fine chemicals.« less

Amination of electrophilic aromatic compounds by vicarious nucleophilic substitution

DOEpatents

Mitchell, Alexander R.; Pagoria, Philip F.; Schmidt, Robert D.

2000-01-01

The present invention relates to a process to aminate electrophilic aromatic compounds by vicarious nucleophilic substitution of hydrogen using quaternary hydrazinium salts. The use of trialkylhydrazinium halide, e.g., trimethylhydrazinium iodide, as well as hydroxylamine, alkoxylamines, and 4-amino-1,2,4-triazole to produce aminated aromatic structures, such as 1,3-diamino-2,4,6-trinitrobenzene (DATB), 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and 3,5-diamino-2,4,6-trinitrotoluene (DATNT), is described. DATB and TATB are useful insensitive high explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).

Ligand- and base-free copper(II)-catalyzed C-N bond formation: cross-coupling reactions of organoboron compounds with aliphatic amines and anilines.

PubMed

Quach, Tan D; Batey, Robert A

2003-11-13

[reaction: see text] A ligandless and base-free Cu-catalyzed protocol for the cross-coupling of arylboronic acids and potassium aryltrifluoroborate salts with primary and secondary aliphatic amines and anilines is described. The process utilizes catalytic copper(II) acetate monohydrate and 4 A molecular sieves in dichloromethane at slightly elevated temperatures under an atmosphere of oxygen. A broad range of functional groups are tolerated on both of the cross-coupling partners.

Efficient CO2 capture by tertiary amine-functionalized ionic liquids through Li+-stabilized zwitterionic adduct formation

PubMed Central

Yang, Zhen-Zhen

2014-01-01

Summary Highly efficient CO2 absorption was realized through formation of zwitterionic adducts, combining synthetic strategies to ionic liquids (ILs) and coordination. The essence of our strategy is to make use of multidentate cation coordination between Li+ and an organic base. Also PEG-functionalized organic bases were employed to enhance the CO2-philicity. The ILs were reacted with CO2 to form the zwitterionic adduct. Coordination effects between various lithium salts and neutral ligands, as well as the CO2 capacity of the chelated ILs obtained were investigated. For example, the CO2 capacity of PEG150MeBu2N increased steadily from 0.10 to 0.66 (mol CO2 absorbed per mol of base) through the formation of zwitterionic adducts being stabilized by Li+. PMID:25246955

Synthesis, spectral, and anti-microbial studies of thioiminium iodides and amine hydrochlorides.

PubMed

Britto, Sebastian; Renaud, Philippe; Nallu, Maruthai

2014-01-01

To avoid the undesired deprotonation during the addition of organolithium and organomagnesium reagents to ketones, the thioiminium salts, easily prepared from lactams and amides are converted into 2,2-disubstituted and 2-monosubstituted amines by reaction with simple nucleophiles such as organocerium and organocopper reagents. The reaction of thioiminium iodides with organocerium reagents derived by transmetalation of corresponding lithium reagents with anhydrous cerium(III) chloride has been investigated. These thioiminium iodides act as good electrophiles and accept alkylceriums towards bisaddition. The newly synthesized amines have been characterized by 1H and 13C NMR, IR and mass spectra. The amines have been converted into their hydrochlorides and characterized by COSY. These hydrochlorides have been subjected to antimicrobial screening with clinically isolated microorganisms, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans. The hydrochlorides show quite good activity against these bacteria and fungus. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of Bronsted Acids and Bases, and Lewis Acid (Sn(2+)) on the Regiochemistry of the Reaction of Amines with Trifluoromethyl-β-diketones: Reaction of 3-Aminopyrrole to Selectively Produce Regioisomeric 1H-Pyrrolo[3,2-b]pyridines.

PubMed

De Rosa, Michael; Arnold, David; Hartline, Douglas; Truong, Linda; Verner, Roman; Wang, Tianwei; Westin, Christian

2015-12-18

Reaction of 3-aminopyrrole (as its salt) with trifluoromethyl-β-diketones gave γ-1H-pyrrolo[3,2-b]pyridines via reaction at the less reactive carbonyl group. The trifluoromethyl group increased the electrophilicity of the adjacent carbonyl group and decreased the basicity of the hydroxyl group of the CF3 amino alcohol formed. This amino alcohol was formed faster, but its subsequent dehydration to the β-enaminone was slow resulting in the preferential formation of the γ-regioisomer. Reaction of 4,4,4-trifluoro-1-phenyl-1,3-butadione with 3-aminopyrrole was carried out using a series of 6 amine buffers. Yields of the α-1H-pyrrolo[3,2-b]pyridine increased as the pKa of the amine buffer decreased. Surprisingly the yield went down at higher pKas. There was a change in mechanism as the reaction mixture became more basic. With strong amines trifluoromethyl-β-diketones were present mainly or completely as the enolate. Under reductive conditions (3-nitropyrrole/Sn/AcOH/trifluoromethyl-β-diketone) the α-1H-pyrrolo[3,2-b]pyridine was the major product as a result of Lewis acid catalysis by Sn(2+). Similar α-regiochemistry was observed when the reaction of the 3-aminopyrrole salt with trifluoromethyl-β-diketones was carried out in the presence of base and tin(II) acetate.

Hydrogen bonded 1D-3D supramolecular structures from Benzylamine and organic acidic components

NASA Astrophysics Data System (ADS)

Gao, Xingjun; Li, XiaoLiang; Jin, Shouwen; Hu, Kaikai; Guo, Jianzhong; Guo, Ming; Xu, Weiqiang; Wang, Daqi

2018-03-01

Cocrystallization of the commonly available organic amine, benzylamine, with a series of organic acids afforded a total of seven organic salts with the compositions: (benzylamine)2: (p-nitrophenol)2: (H2O) (1) [(HL)2+⋯(npl-)2⋯(H2O), npl- = p-nitrophenolate], (benzylamine): (4-tert-butylbenzoic acid) (2) [(HL+)⋯(tba-), tba- = 4-tert-butylbenzoate], (benzylamine): (3,4-dichlorobenzoic acid) (3) [(HL+)⋯dcba-), dcba- = 3,4-dichlorobenzoate], (benzylamine): (2,5-dihydroxybenzoic acid) (4) [(HL+)⋯(dhba-), dhba- = 2,5-dihydroxybenzoate], (benzylamine): (2-bromo-but-2-enedioic acid) (5) [(HL+)⋯(Hbba-), Hbba- = 2-bromo-hydrogenbut-2-enedioate], (benzylamine): (2,6-pyridinedicarboxylic acid) (6) [(HL+)⋯(Hpdc-), Hpdc- = 2,6-pyridine hydrogendicarboxylate], and (benzylamine)2: (3-nitrophthalic acid): 2(H2O) (7) [(HL+)2⋯(npa2-)⋯(H2O)2, npa2- = 3-nitrophthalate]. The seven salts have been characterised by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The results reveal that among the seven investigated crystals the NH2 in the benzylamine are protonated when the organic acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted Nsbnd H⋯O hydrogen bond between the NH3+ and deprotonated acidic groups. Except the Nsbnd H⋯O hydrogen bond, the Osbnd H⋯O hydrogen bonds (charge assisted or neutral) were also found at the salts 1, 4, 5, 6, and 7. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O/CH2sbnd O, CH-π/CH2-π, Cπ-Cπ, Osbnd O, O-Cπ, O-π, and Cl-π associations also contribute to the stabilization and expansion of the total high-dimensional framework structures. For the coexistence of the various weak nonbonding interactions, these structures adopted a variety of supramolecular synthons of R12(4), R12(5), R21(5), R22(6), R22(10), R32(6), R32(9), R33(9), R42(8), R42(9), R43(10), R44(12), R44(20), R52(9), and R64(12).

Diclofenac Salts, VIII. Effect of the Counterions on the Permeation through Porcine Membrane from Aqueous Saturated Solutions.

PubMed

Fini, Adamo; Bassini, Glenda; Monastero, Annamaria; Cavallari, Cristina

2012-09-12

The following bases: monoethylamine (EtA), diethylamine (DEtA), triethylamine (TEtA), monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), pyrrolidine (Py), piperidine (Pp), morpholine (M), piperazine (Pz) and their N-2-hydroxyethyl (HE) analogs were employed to prepare 14 diclofenac salts. The salts were re-crystallized from water in order to obtain forms that are stable in the presence of water. Vertical Franz-type cells with a diffusional surface area of 9.62 cm2 were used to study the permeation of these diclofenac salts from their saturated solutions through an internal pig ear membrane. The receptor compartments of the cells contained 100 mL of phosphate buffer (pH 7.4); a saturated solution (5 mL) of each salt was placed in the donor compartment, thermostated at 37 °C. Aliquots were withdrawn at predetermined time intervals over 8 h and then immediately analyzed by HPLC. Fluxes were determined by plotting the permeated amount, normalized for the membrane surface area versus time. Permeation coefficients were obtained dividing the flux values J by the concentration of the releasing phase-that is, water solubility of each salt. Experimental results show that fluxes could be measured when diclofenac salts with aliphatic amines are released from a saturated aqueous solution. Different chemical species (acid, anion, ion pairs) contribute to permeation of the anti-inflammatory agent even though ion-pairs could be hypothesized to operate to a greater extent. Permeation coefficients were found higher when the counterion contains a ring; while hydroxy groups alone do not appear to play an important role, the ring could sustain permeation, disrupting the organized domains of the membrane.

Diclofenac Salts, VIII. Effect of the Counterions on the Permeation through Porcine Membrane from Aqueous Saturated Solutions

PubMed Central

Fini, Adamo; Bassini, Glenda; Monastero, Annamaria; Cavallari, Cristina

2012-01-01

The following bases: monoethylamine (EtA), diethylamine (DEtA), triethylamine (TEtA), monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), pyrrolidine (Py), piperidine (Pp), morpholine (M), piperazine (Pz) and their N-2-hydroxyethyl (HE) analogs were employed to prepare 14 diclofenac salts. The salts were re-crystallized from water in order to obtain forms that are stable in the presence of water. Vertical Franz-type cells with a diffusional surface area of 9.62 cm2 were used to study the permeation of these diclofenac salts from their saturated solutions through an internal pig ear membrane. The receptor compartments of the cells contained 100 mL of phosphate buffer (pH 7.4); a saturated solution (5 mL) of each salt was placed in the donor compartment, thermostated at 37 °C. Aliquots were withdrawn at predetermined time intervals over 8 h and then immediately analyzed by HPLC. Fluxes were determined by plotting the permeated amount, normalized for the membrane surface area versus time. Permeation coefficients were obtained dividing the flux values J by the concentration of the releasing phase—that is, water solubility of each salt. Experimental results show that fluxes could be measured when diclofenac salts with aliphatic amines are released from a saturated aqueous solution. Different chemical species (acid, anion, ion pairs) contribute to permeation of the anti-inflammatory agent even though ion-pairs could be hypothesized to operate to a greater extent. Permeation coefficients were found higher when the counterion contains a ring; while hydroxy groups alone do not appear to play an important role, the ring could sustain permeation, disrupting the organized domains of the membrane. PMID:24300300

40 CFR 721.9795 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl) amino...

Code of Federal Regulations, 2011 CFR

2011-07-01

... benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl)amino]-, disodium salt... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzenesulfonic acid, 2,2â²-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl) amino]-, disodium salt, substituted with dialkyl amines...

40 CFR 721.9795 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl) amino...

Code of Federal Regulations, 2010 CFR

2010-07-01

... benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl)amino]-, disodium salt... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzenesulfonic acid, 2,2â²-(1,2-ethenediyl)bis[(4,6-dichloro-1,3,5-triazin-2-yl) amino]-, disodium salt, substituted with dialkyl amines...

Determination of amines used in the oil and gas industry (upstream section) by ion chromatography.

PubMed

Kadnar, R

1999-07-30

During production and purification of crude oil and natural gas several different amines are used as chemicals or operating materials, e.g. film forming long chain amines as corrosion inhibitors, steam volatile amines for pH correction and corrosion protection, alkanolamines as absorbents in sour gas treatment plants, etc. For analytical checks, e.g. determination of corrosion inhibitor concentration in produced media, classical chemical methods are used predominantly, because most of them can be performed in small field laboratories. Some amines, especially the small molecular aliphatic and heterocyclic amines can also be determined by ion chromatography. In our laboratory two types of separation columns (IonPac CS10 and CS12A) were available for ion chromatographic separation. The analysis of the amines in low-salt-containing water, soft water or steam condensate can be performed without problems. The presence of alkali and/or alkaline earth ions in the sample can lead to coelution with these ions, to poor peak resolution or enhanced analysis times, depending on the chromatographic conditions. This work shows some examples of ion chromatography applications for the determination of low-molecular-mass ethanolamines, morpholine and piperazine and discusses the possible interferences and troubles caused by alkali and alkaline earth ions in the matrix.

Rapid simultaneous determination of amines and organic acids in citrus using high-performance liquid chromatography.

PubMed

Uckoo, Ram M; Jayaprakasha, Guddadarangavvanahally K; Nelson, Shad D; Patil, Bhimanagouda S

2011-01-15

Rapid analytical method for the simultaneous separation and determination of amines and organic acids is a vital interest for quality control of citrus and their products. In the present study, a simultaneous high performance liquid chromatography (HPLC) method for the rapid separation of three amines and two organic acids was developed. Chromatographic separation of compounds was achieved using Xbridge C(18) column at ambient temperature, with an isocratic mobile phase of 3mM phosphoric acid at a flow rate of 1.0 mL min(-1). A photodiode array (PDA) detector was used to monitor the eluent at 223 nm and 254 nm with a total analysis time of 10 min. Extraction of amines and organic acids from citrus juice was optimized. The method was validated by tests of linearity, recovery, precision and ruggedness. The limit of detection (LOD) and limit of quantification (LOQ) for amines and ascorbic acid were determined to be 5 ng and 9.8 ng, respectively. All calibration curves showed good linearity (R(2) ≥ 0.9999) within the test ranges. The recoveries of the amines and organic acids ranged between 84% and 117%. The identity of each peak was confirmed by mass spectral (MS) analysis. The developed method was successfully applied to analyze the content of amines and organic acids in six different species and two varieties of citrus. Results indicate that mandarin and Marrs sweet orange contain high level of amines, while pummelo and Rio Red grapefruit had high content of ascorbic acid (137-251 μg mL(-1)) and citric acid (5-22 mg mL(-1)). Synephrine was the major amine present in Clementine (114 μg mL(-1)) and Marrs sweet orange (85 μg mL(-1)). To the best of our knowledge, this is the first report on simultaneous separation and quantification of amines and organic acids in Marrs sweet orange, Meyer lemon, Nova tangerine, Clementine, Ugli tangelo and Wekiwa tangelo. Copyright © 2010 Elsevier B.V. All rights reserved.

Synthesis and evaluation of energetic materials

NASA Astrophysics Data System (ADS)

Santhosh, G.

Over the years new generations of propellants and explosives are being developed. High performance and pollution prevention issues have become the subject of interest in recent years. Desired properties of these materials are a halogen-free, nitrogen and oxygen rich molecular composition with high density and a positive heat of formation. The dinitramide anion is a new oxy anion of nitrogen and forms salts with variety of metal, organic and inorganic cations. Particular interest is in ammonium dinitramide (ADN, NH4N(NO 2)2) which is a potentially useful energetic oxidizer. ADN is considered as one of the most promising substitutes for ammonium perchlorate (AP, NH4ClO4) in currently used composite propellants. It is unique among energetic materials in that it has no carbon or chlorine; its combustion products are not detrimental to the atmosphere. Unquestionable advantage of ADN over AP is the significant improvement in the performance of solid rocket motors by 5-15%. The present thesis is centered on the experimental results along with discussion of some of the most pertinent aspects related to the synthesis and characterization of few dinitramide salts. The chemistry, mechanism and kinetics of the formation of dinitramide salts by nitration of deactivated amines are investigated. The evaluation of the thermal and spectral properties along with the adsorption and thermal decomposition characteristics of the dinitramide salts are also explored in this thesis.

Metal-Free Oxidation of Primary Amines to Nitriles through Coupled Catalytic Cycles.

PubMed

Lambert, Kyle M; Bobbitt, James M; Eldirany, Sherif A; Kissane, Liam E; Sheridan, Rose K; Stempel, Zachary D; Sternberg, Francis H; Bailey, William F

2016-04-04

Synergism among several intertwined catalytic cycles allows for selective, room temperature oxidation of primary amines to the corresponding nitriles in 85-98% isolated yield. This metal-free, scalable, operationally simple method employs a catalytic quantity of 4-acetamido-TEMPO (ACT; TEMPO=2,2,6,6-tetramethylpiperidine N-oxide) radical and the inexpensive, environmentally benign triple salt oxone as the terminal oxidant under mild conditions. Simple filtration of the reaction mixture through silica gel affords pure nitrile products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

21 CFR 175.105 - Adhesives.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-isobutyronitrile Balata rubber Barium acetate Barium peroxide Barium sulfate Bentonite Benzene (benzol) 1,4... Chromium potassium sulfate Cobaltous acetate Coconut fatty acid amine salt of tetrachlorophenol For use as... sulfonamide Fats and oils derived from animal or vegetable sources, and the hydrogenated, sulfated, or...

21 CFR 175.105 - Adhesives.

Code of Federal Regulations, 2011 CFR

2011-04-01

...-isobutyronitrile Balata rubber Barium acetate Barium peroxide Barium sulfate Bentonite Benzene (benzol) 1,4... Chromium potassium sulfate Cobaltous acetate Coconut fatty acid amine salt of tetrachlorophenol For use as... sulfonamide Fats and oils derived from animal or vegetable sources, and the hydrogenated, sulfated, or...

Concentration, size distribution and dry deposition of amines in atmospheric particles of urban Guangzhou, China

NASA Astrophysics Data System (ADS)

Liu, Fengxian; Bi, Xinhui; Zhang, Guohua; Peng, Long; Lian, Xiufeng; Lu, Huiying; Fu, Yuzhen; Wang, Xinming; Peng, Ping'an; Sheng, Guoying

2017-12-01

Size-segregated PM10 samples were collected in Guangzhou, China during autumn of 2014. Nine amines, including seven aliphatic amines and two heterocyclic amines, were detected using a gas chromatography-mass spectrometer after derivatization by benzenesulfonyl chloride. The total concentration of the nine amines (Ʃamines) was 79.6-140.9 ng m-3 in PM10. The most abundant species was methylamine (MA), which had a concentration of 29.2-70.1 ng m-3. MA, dimethylamine (DMA), diethylamine (DEA) and dibutylamine (DBA) were the predominant amines in the samples and accounted for approximately 80% of Ʃamines in each size segment. Two heterocyclic amines, pyrrolidine (PYR) and morpholine (MOR), were detected in all samples and had average concentrations of 1.14 ± 0.37 and 1.89 ± 0.64 ng m-3, respectively, in particles with aerodynamic diameters < 3 μm. More than 80% of Ʃamines were found in particles with diameters <1.5 μm, indicating that amines are mainly enriched in fine particles. All amines exhibited a bimodal distribution with a fine mode at 0.49-1.5 μm and a coarse mode at 7.2-10 μm. The maximum contributions of amines to particles (0.21%) and amines-N to water-soluble organic nitrogen (WSON) (3.1%) were found at the sizes < 0.49 μm. The maximum contribution of amines-C to water-soluble organic carbon (WSOC) was 1.6% over the size range of 0.95-1.5 μm. The molar ratio of Ʃamines to ammonium ranged from 0.0068 to 0.0107 in particles with diameters <1.5 μm, and the maximum ratio occurred in the smallest particles (diameter< 0.49 μm). The average dry deposition flux and velocity of Ʃamines in PM10 were 7.9 ± 1.6 μg m-2 d-1 and 0.084 ± 0.0021 cm s-1, respectively. The results of this study provide essential information on the contribution of amines to secondary organic aerosols and dry removal mechanisms in urban areas.

The molecular assembly of the ionic liquid/aliphatic carboxylic acid/aliphatic amine as effective and safety transdermal permeation enhancers.

PubMed

Kubota, Koji; Shibata, Akira; Yamaguchi, Toshikazu

2016-04-30

In spite of numerous advantages, transdermal drug delivery systems are unfeasible for most drugs because of the barrier effect of the stratum corneum. Ionic liquids were recently used to enhance transdermal drug delivery by improving drug solubility. In the present study, safe and effective ionic liquids for transdermal absorption were obtained as salts generated by a neutralization reaction between highly biocompatible aliphatic carboxylic acids (octanoic acid or isostearic acid) and aliphatic amines (diisopropanolamine or triisopropanolamine) (Medrx Co., Ltd., 2009). The mechanism of skin permeability enhancement by ionic liquids was investigated by hydrophilic phenol red and hydrophobic tulobuterol. Further, the skin permeation enhancing effect was remarkably superior in the acid excess state rather than the neutralization state. Infrared absorption spectrum analysis confirmed that ionic liquids/aliphatic carboxylic acid/aliphatic amine are coexisting at all mixing states. In the acid excess state, ionic liquids interact with aliphatic carboxylic acids via hydrogen bonds. Thus, the skin permeation enhancing effect is not caused by the ionic liquid alone. The "liquid salt mixture," referred to as a complex of ingredients coexisting with ionic liquids, forms a molecular assembly incorporating hydrophilic drug. This molecular assembly was considered an effective and safety enhancer of transdermal drug permeation. Copyright © 2016. Published by Elsevier B.V.

Secondary Amine Functional Disiloxanes as CO2 Sorbents

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Brien, MJ; Farnum, RL; Perry, RJ

2014-05-01

A series of two different types of secondary amine functional disiloxanes were prepared and screened as CO2 capture solvents. The first group of materials contained RNHCH2CH2CH2 side chains where the R groups were C1-6 alkyls. When R was a primary alkyl group, these materials exhibited CO2 uptake values slightly in excess of theoretical. As the alkyl groups were changed to more sterically hindered secondary or tertiary alkyls, the uptake was less efficient. Heats of absorption values for these materials were generally in the range 2000-2200 kJ/kg of CO2, values significantly lower than those obtained for primary amine functional disiloxanes (2500-2700more » kJ/kg of CO2). Also explored were a series of secondary amine functional disiloxanes with X-CH2CH2NH-CH2CH2CH2 - substituents. When X was an electron-donating group (RO-, R2N-, RO-CH2-) the CO2 uptake was also in excess of theoretical. Interestingly, these compounds were generally found to produce carbamate salts that were flowable, low-viscosity oils. Furthermore, the heat of absorption values determined for these materials were even lower. Most compounds gave values below 2000 kJ/kg of CO2. Overall the most promising results were obtained with a methoxyethylaminopropyl derivative, an ethoxyethylaminopropyl-containing material, and a dimethylaminoethylaminopropyl-based compound. These materials showed excellent CO2 uptake, had low heats of absorption, and produced carbamate salts that were flowable liquids even at room temperature.« less

Algicidal Activity of a Surface-Bonded Organosilicon Quaternary Ammonium Chloride

PubMed Central

Walters, P. A.; Abbott, E. A.; Isquith, A. J.

1973-01-01

The hydrolysis product of a quaternary amine-containing organosilicon salt, 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride, was found to exhibit algicidal activity while chemically bonded to a variety of substrates. Six representative species of Chlorophyta, Cyanophyta, and Chrysophyta were used to evaluate the algicidal activity. Substrate-bonded 14C-labeled organosilicon quaternary ammonium salt when attached to nonwoven fibers was durable to repeated washings, and algicidal activity could not be attributed to slow release of the chemical. Images PMID:4632852

Biodegradation of organic pollutants in saline wastewater by halophilic microorganisms: a review.

PubMed

Castillo-Carvajal, Laura C; Sanz-Martín, José Luis; Barragán-Huerta, Blanca E

2014-01-01

Agro-food, petroleum, textile, and leather industries generate saline wastewater with a high content of organic pollutants such as aromatic hydrocarbons, phenols, nitroaromatics, and azo dyes. Halophilic microorganisms are of increasing interest in industrial waste treatment, due to their ability to degrade hazardous substances efficiently under high salt conditions. However, their full potential remains unexplored. The isolation and identification of halophilic and halotolerant microorganisms from geographically unrelated and geologically diverse hypersaline sites supports their application in bioremediation processes. Past investigations in this field have mainly focused on the elimination of polycyclic aromatic hydrocarbons and phenols, whereas few studies have investigated N-aromatic compounds, such as nitro-substituted compounds, amines, and azo dyes, in saline wastewater. Information regarding the growth conditions and degradation mechanisms of halophilic microorganisms is also limited. In this review, we discuss recent research on the removal of organic pollutants such as organic matter, in terms of chemical oxygen demand (COD), dyes, hydrocarbons, N-aliphatic and N-aromatic compounds, and phenols, in conditions of high salinity. In addition, some proposal pathways for the degradation of aromatic compounds are presented.

Synthesis and characterization of Pd(II)-methyl complexes with N-heterocyclic carbene-amine ligands.

PubMed

Warsink, Stefan; de Boer, Sandra Y; Jongens, Lianne M; Fu, Ching-Feng; Liu, Shiuh-Tzung; Chen, Jwu-Ting; Lutz, Martin; Spek, Anthony L; Elsevier, Cornelis J

2009-09-21

A number of palladium(ii) complexes with a heteroditopic NHC-amine ligand and their precursor silver(i) carbene complexes have been efficiently prepared and their structural features have been investigated. The heteroditopic coordination of this ligand class was unequivocally shown by NMR-spectroscopy and X-ray crystallographic analysis. The neutral and cationic cis-methyl-palladium(NHC) complexes are not prone to reductive elimination, which is normally a major degenerative pathway for this type of complex. In contrast, under carbon monoxide atmosphere rapid reductive elimination of the acyl-imidazolium salt was observed.

1-Amine-1,2,3-triazolium salts with oxidizing anions: A new family of energetic materials with good performance

NASA Astrophysics Data System (ADS)

Zhang, Zhi-Bin; Zhang, Jian-Guo

2018-04-01

A series of 1-amino-1,2,3-triazole (ATZ) based energetic nitrogen-rich salts are prepared by using acid-base neutralization reaction (1:1 M ratio), and fully characterized. Structures of the salts are recrystallized and determined by single-crystal X-ray diffraction, which dominated by a strong hydrogen-bond influence with the densities ranging from 1.692 to 1.868 g cm-3. Thermal behaviors have characterized by using the DSC and TG-DTG technologies. The enthalpies of formation have calculated by using Gaussian 03. The detonation parameters of the salts are determined by using the K-J method, and most salts show promising detonation performances (D: 6699-8231 m s-1, P: 19.2-30.7 GPa), among which the salt of 1-amino-1,2,3-triazolium trinitrophloroglucinate has a detonation properties comparable to RDX. The sensitivities results provided the salts as insensitive energetic materials.

Amine Chemistry at Aqueous Interfaces: The Study of Organic Amines in Neutralizing Acidic Gases at an Air/Water Surface Using Vibrational Sum Frequency Spectroscopy

NASA Astrophysics Data System (ADS)

McWilliams, L.; Wren, S. N.; Valley, N. A.; Richmond, G.

2014-12-01

Small organic bases have been measured in atmospheric samples, with their sources ranging from industrial processing to animal husbandry. These small organic amines are often highly soluble, being found in atmospheric condensed phases such as fogwater and rainwater. Additionally, they display acid-neutralization ability often greater than ammonia, yet little is known regarding their kinetic and thermodynamic properties. This presentation will describe the molecular level details of a model amine system at the vapor/liquid interface in the presence of acidic gas. We find that this amine system shows very unique properties in terms of its bonding, structure, and orientation at aqueous surfaces. The results of our studies using a combination of computation, vibrational sum frequency spectroscopy, and surface tension will report the properties inherent to these atmospherically relevant species at aqueous surfaces.

Nitrogen-rich salts based on the energetic [monoaquabis(N,N-bis(1H-tetrazol-5-yl)amine)-zinc(II)] anion: a promising design in the development of new energetic materials.

PubMed

Li, Fugang; Bi, Yangang; Zhao, Wenyuan; Zhang, Tonglai; Zhou, Zunning; Yang, Li

2015-02-16

Nitrogen-rich energetic salts involving various cations (lithium, 1; ammonium, 2; hydrazinium, 3; hydroxylammonium, 4; guanidinium, 5; aminoguanidinium, 6; diaminoguanidinium, 7; and triaminoguanidinium, 8) based on nitrogen-rich anion [Zn(BTA)2(H2O)](2-) (N% = 65.37, BTA = N,N-bis[1H-tetrazol-5-yl]amine anion) were synthesized with a simple method. The crystal structures of all compounds except 1, 2, and 6 were determined by single-crystal X-ray diffraction and fully characterized by elemental analysis and FT-IR spectroscopy. The thermal stabilities were investigated by differential scanning calorimetry (DSC). The DSC results show that all compounds exhibit high thermal stabilities (decomposition temperature >200 °C). Additionally, the heats of formation were calculated on the basis of the experimental constant-volume energies of combustion measured by using bomb calorimetry. Lastly, the sensitivities toward impact and friction were assessed according to Bundesamt für Materialforschung (BAM) standard methods.

Amine oxidases as important agents of pathological processes of rhabdomyolysis in rats.

PubMed

Gudkova, O O; Latyshko, N V; Shandrenko, S G

2016-01-01

In this study we have tested an idea on the important role of amine oxidases (semicarbazide-sensitive amine oxidase, diamine oxidase, polyamine oxidase) as an additional source of oxidative/carbonyl stress under glycerol-induced rhabdomyolysis, since the enhanced formation of reactive oxygen species and reactive carbonyl species in a variety of tissues is linked to various diseases. In our experiments we used the sensitive fluorescent method devised for estimation of amine oxidases activity in the rat kidney and thymus as targeted organs under rhabdomyolysis. We have found in vivo the multiple rises in activity of semicarbazide-sensitive amine oxidase, diamine oxidase, polyamine oxidase (2-4.5 times) in the corresponding cell fractions, whole cells or their lysates at the 3-6th day after glycerol injection. Aberrant antioxidant activities depended on rhabdomyolysis stage and had organ specificity. Additional treatment of animals with metal chelator ‘Unithiol’ adjusted only the activity of antioxidant enzymes but not amine oxidases in both organs. Furthermore the in vitro experiment showed that Fenton reaction (hydrogen peroxide in the presence of iron) products alone had no effect on semicarbazide-sensitive amine oxidase activity in rat liver cell fraction whereas supplementation with methylglyoxal resulted in its significant 2.5-fold enhancement. Combined action of the both agents had additive effect on semicarbazide-sensitive amine oxidase activity. We can assume that biogenic amine and polyamine catabolism by amine oxidases is upregulated by oxidative and carbonyl stress factors directly under rhabdomyolysis progression, and the increase in catabolic products concentration contributes to tissue damage in glycerol-induced acute renal failure and apoptosis stimulation in thymus.

A Simple Secondary Amine Synthesis: Reductive Amination Using Sodium Triacetoxyborohydride

NASA Astrophysics Data System (ADS)

Carlson, Merle W.; Ciszewski, James T.; Bhatti, Micah M.; Swanson, Wesley F.; Wilson, Anne M.

2000-02-01

We present a reductive amination experiment for a second-semester organic chemistry class. It utilizes an imine intermediate and sodium triacetoxyborohydride, a mild reducing agent. The progress of the reaction is followed by TLC as the starting materials (the aldehyde and primary amine), the imine intermediate, and the secondary amine product are visible under ultraviolet light. This experiment provides an introduction to the observation of intermediates, the synthesis of amines, and the concept of mild reducing agents.

Dynamic Multi-Component Hemiaminal Assembly

PubMed Central

You, Lei; Long, S. Reid; Lynch, Vincent M.

2012-01-01

A simple approach to generating in situ metal templated tris-(2-picolyl)amine-like multi-component assemblies with potential applications in molecular recognition and sensing is reported. The assembly is based on the reversible covalent association between di-(2-picolyl)amine and aldehydes. Zinc ion is the best for inducing assembly among the metal salts investigated, while 2-picolinaldehyde is the best among the heterocyclic aldehydes studied. Although an equilibrium constant of 6.6 * 103 M-1 was measured for the assembly formed by 2-picolinaldehdye, di-(2-picolyl)amine, and zinc triflate, the equilibrium constants for other systems are in the 102 M-1 range. X-ray structural analysis revealed that zinc adopts a trigonal bipyramidal geometry within the assembled ligand. The diversity and equilibrium of the assemblies are readily altered by simply changing concentrations, varying components, or adding counter anions. PMID:21919095

Extractive separation of uranium and zirconium sulfates by amines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schroetterova, D.; Nekovar, P.; Mrnka, M.

1992-04-01

This paper describes an amine extraction process for zirconium and uranium separation. The behaviour of an extraction system containing uranium (VI) sulfate, zirconium (IV) sulfate, 0.2 and 0.5 M sulfuric acid (as the original aqueous phase), tertiary amine tri-n-lauryl- amine or primary amine Primene JMT in benzene (as the original organic phase) is discussed on the basis of equilibrium data. The measured dependences show that the degree of extraction of zirconium at the sulfuric acid concentration of 0.5 M and above is only slightly affected by a presence of uranium in solution. From this surprising behaviour it follows that zirconiummore » may be employed for the displacement of uranium from the organic phase. This effect is more pronounced with the primary amine Primene JMT than with TLA. 29 refs., 4 figs., 1 tab.« less

The Significance of Interfacial Water Structure in Soluble Salt Flotation Systems.

PubMed

Hancer, M.; Celik, M. S.; Miller, J. D.

2001-03-01

Flotation of soluble salts with dodecyl amine hydrochloride (DAH) and sodium dodecyl sulfate (SDS) collectors has demonstrated that the interfacial water structure and hydration states of soluble salt surfaces together with the precipitation tendency of the corresponding collector salts are of considerable importance in explaining their flotation behavior. In particular, the high concentration of ions in these soluble salt brines and their hydration appear to modify the bulk and interfacial structure of water as revealed by contact angle measurements and this effect is shown to be an important feature in the flotation chemistry of soluble salt minerals including alkali halide and alkali oxyanion salts. Depending on characteristic chemical features (salt type), the salt can serve either as a structure maker, in which intermolecular hydrogen bonding between water molecules is facilitated, or as a structure breaker, in which intermolecular hydrogen bonding between water molecules is disrupted. For structure making salts the brine completely wets the salt surface and no contact angle can be measured. For structure breaking salts the brine does not completely wet the salt surface and a finite contact angle is measured. In this regard it has been found that soluble salt flotation either with the cationic DAH or anionic SDS collector is possible only if the salt is a structure breaker. Copyright 2001 Academic Press.

Distribution and metabolism of quaternary amines in salt marshes

NASA Technical Reports Server (NTRS)

King, Gary M.

1985-01-01

Quaternary amines such as glycine betaine (GBT) are common osmotically active solutes in much of the marine biota. GBT is accumulated by various bacteria, algae, higher plants, invertebrates, and vertebrates in response to salinity or water stresses; in some species, GBT occurs at tens to hundreds of millimolar concentrations and can account for a significant fraction of total nitrogen. Initial studies suggest that GBT is readily converted to two potential methane precursors, trimethylamine (TMA) and acetate, in anoxic sediments. TMA is apparently the most important methane precursor in surface sediments containing sulfate reducing bacteria. In salt marshes, the bulk of the methane formed may be due to the metabolism of TMA rather than other substrates. Current research is focussed on testing this hypothesis and on determining the role of quaternary amino osmoregulatory solutes in methane fluxes from marine environments. Preliminary studies have dealt with several problems: (1) determination of GBT concentrations in the dominant flora and fauna of salt marshes; (2) synthesis of radiolabelled GBT for metabolic studies; and (3) determination of fates of BGT in marine sediments using radiotracers. Both GC and HPLC techniques have been used to assay GBT concentrations in plant and animal tissues. S. alterniflora is probably the only significant source of GBT (and indirectly of methane) since the biomass and distribution of most other species is limited. Current estimates suggest that S. alterniflora GBT could account for most of the methane efflux from salt marshes.

Effect of heat stable salts on MDEA solution corrosivity: Part 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rooney, P.C.; DuPart, M.S.; Bacon, T.R.

1997-04-01

A comprehensive coupon corrosion testing program was undertaken to address the effect of various heat stable salts on methyldiethanolamine (MDEA) corrosivity to carbon steel and various stainless steels. Corrosion rates of carbon steel, 304SS, 316SS and 410SS liquid and vapor coupons towards MDEA, and MDEA containing various anions, at 180 F and 250 F, were measured in a reactor. Corrosion results of two refinery plant solutions before and after caustic neutralization were also performed. Based on these results, guidelines were determined for heat stable amine salt (HSAS) levels of oxalates, sulfates, formates, acetates and thiosulfates. In addition, caustic neutralization guidelinesmore » for MDEA heat stable salts were determined. Ongoing results include MDEA corrosivity with succinates, and malonates, glycolates, SO{sub 2} and ammonia.« less

Effect of electrolyte on surface free energy components of feldspar minerals using thin-layer wicking method.

PubMed

Karagüzel, C; Can, M F; Sönmez, E; Celik, M S

2005-05-01

Application of the thin-layer wicking (TLW) technique on powdered minerals is useful for characterizing their surfaces. Albite (Na-feldspar) and orthoclase (K-feldspar) are feldspar minerals which are frequently found in the same matrix. Despite similarities in their physicochemical properties, separation of these minerals from each other by flotation is generally possible in the presence of monovalent salts such as NaCl. Both albite and orthoclase exhibit the same microflotation properties and rather close electrokinetic profiles in the absence of salt. In this study, contact angles of albite and orthoclase determined by the TLW technique yielded close values in the absence and presence of amine collector. While the calculated surface energies and their components determined using contact angle data reveal that the energy terms remain farther apart in the absence of the collector, the differences narrow down at collector concentrations where full flotation recoveries are obtained. However, the effect of addition of NaCl on contact angles and surface free energy components at constant amine concentration indicates that albite is significantly affected by salt addition, whereas orthoclase remains marginally affected. This interesting finding is explained on the basis of ion-exchange properties, the stability of the interface, flotation data, and zeta potential data in the presence of NaCl.

Solvent-Free Reductive Amination: An Organic Chemistry Experiment

ERIC Educational Resources Information Center

Goldstein, Steven W.; Cross, Amely V.

2015-01-01

The reductive amination reaction between an amine and an aldehyde or ketone is an important method to add an additional alkyl group to an amine nitrogen. In this experiment, students react a selection of benzylamines with aldehydes to form the corresponding imines. These imines are reduced with a mixture of "p"-toluenesulfonic acid…

Solution-Processed Solar Cells via Nanocrystal Inks and Molecular Solutions

NASA Astrophysics Data System (ADS)

Miskin, Caleb K.

On February 15, 2008 the National Academy of Engineering unveiled their fourteen grand challenges of engineering for the 21st century. At the top of the list and voted by the public as the most important challenge was the thrust to make solar energy economical. My research has been dedicated to solving this millennial challenge by developing routes to high-efficiency, solution-processed photovoltaics (PV) for low-cost and low-energy manufacturing. My research has primarily advanced two methods for solution processed PV. In one method, semiconducting nanocrystals are synthesized and then suspended in an appropriate solvent to form an ink. The ink is then applied to a substrate by a variety of high-throughput methods such as spray coating or doctor blading and then annealed to form a polycrystalline absorber layer for solar energy. I have applied this method with great success to Cu2ZnSnS 4, a promising earth-abundant, non-toxic semiconductor. A challenge with this material is its propensity to form binary and ternary undesired phases. Using advanced nano-characterization techniques, my colleagues and I have been able to determine the spatially resolved composition of these nanoparticles and have found them to be highly non-uniform. In addition, I developed synthesis techniques aimed at controlling the nucleation and growth of this material to improve nanocrystal compositional homogeneity. Though particles produced in this work still exhibit some non-uniformities, they are greatly improved. When combined with optimized fabrication techniques, I have been able to advance the efficiency of nanocrystal ink based solar cells of CZTS from 7.2 to 9.0 percent in our lab. Another promising route to solution-processed PV is by directly coating molecular precursor solutions (rather than first forming nanocrystals) and annealing the coating to form the polycrystalline solar absorber layer. Unfortunately, a major challenge is that many metals, metal salts, and chalcogens that would be useful precursors to such films have poor solubility in organic solvents compatible with roll-to-roll manufacturing techniques. Interestingly, we have found that mixtures of commonly available thiols and amines are able to dissolve at room temperature and pressure a host of metals and salts that are otherwise insoluble in either solvent by itself. In this work, I have primarily focused on CdTe--which has been by far the most successful technology in terms of production cost ($/peak watt) and energy payback time for thin-film solar cells. In this research thrust I demonstrate for the first time the fabrication of CdTe thin-films via a solution-processed molecular precursor approach by dissolving CdCl2 and Te in ethylenediamine and 1-propanethiol. The films are formed by spin-coating thin layers of the solution and then annealing each layer until a 1.5 mum thick film is achieved. I have achieved 0.5% efficient devices by this method. As thiol-amine mixtures have the potential to leave residual sulfur in these films, other novel solvent systems are presented as future work. While amine-thiol mixtures are excellent solvents for many materials, they do not dissolve lead chalcogenides with ease. I leverage this to develop room-temperature synthesis routes to PbS, PbSe, PbTe, and PbSxSe 1-x nanoparticles. This is achieved by mixing a lead salt dissolved in thiol-amine with a chalcogen dissolved in thiol-amine at room temperature. We find that when particles produced in this manner are pressed into pellets, they show comparable thermoelectric performance to more complicated and energy intensive synthesis techniques. Ultimately, we wish to enable the use of these particles in room-temperature fabricated quantum dot solar cells. This requires the synthesis of highly monodisperse, stable colloids and is the subject of future work using thiol-amine mixtures and related aqueous analogues.

Methane production and simultaneous sulphate reduction in anoxic, salt marsh sediments

USGS Publications Warehouse

Oremland, R.S.; Marsh, L.M.; Polcin, S.

1982-01-01

It has been generally believed that sulphate reduction precludes methane generation during diagenesis of anoxic sediments1,2. Because most biogenic methane formed in nature is thought to derive either from acetate cleavage or by hydrogen reduction of carbon dioxide3-6, the removal of these compounds by the energetically more efficient sulphate-reducing bacteria can impose a substrate limitation on methanogenic bacteria 7-9. However, two known species of methanogens, Methanosarcina barkeri and Methanococcus mazei, can grow on and produce methane from methanol and methylated amines10-13. In addition, these compounds stimulate methane production by bacterial enrichments from the rumen11,14 and aquatic muds13,14. Methanol can enter anaerobic food webs through bacterial degradation of lignins15 or pectin16, and methylated amines can be produced either from decomposition of substances like choline, creatine and betaine13,14 or by bacterial reduction of trimethylamine oxide17, a common metabolite and excretory product of marine animals. However, the relative importance of methanol and methylated amines as precursors of methane in sediments has not been previously examined. We now report that methanol and trimethylamine are important substrates for methanogenic bacteria in salt marsh sediments and that these compounds may account for the bulk of methane produced therein. Furthermore, because these compounds do not stimulate sulphate reduction, methanogenesis and sulphate reduction can operate concurrently in sulphate-containing anoxic sediments. ?? 1982 Nature Publishing Group.

Semipermeable polymers and method for producing same

DOEpatents

Buschmann, Wayne E [Boulder, CO

2012-04-03

A polyamide membrane comprising reaction product of an anhydrous solution comprising an anhydrous solvent, at least one polyfunctional secondary amine and a pre-polymer deposition catalyst; and an anhydrous, organic solvent solution comprising a polyfunctional aromatic amine-reactive reactant comprising one ring. A composite semipermeable membrane comprising the polyamide membrane on a porous support. A method of making a composite semipermeable membrane by coating a porous support with an anhydrous solution comprising an anhydrous solvent, a polyfunctional secondary amine and a pre-polymer deposition catalyst, to form an activated pre-polymer layer on the porous support and contacting the activated pre-polymer layer with an anhydrous, organic solvent solution comprising a polyfunctional amine-reactive reactant to interfacially condense the amine-reactive reactant with the polyfunctional secondary amine, thereby forming a cross-linked, interfacial polyamide layer on the porous support. A method of impregnating a composite semipermeable membrane with nanoparticles selected from heavy metals and/or oxides of heavy metals.

Phenanthroline-based metal–organic frameworks for Fe-catalyzed C sp3 –H amination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thacker, Nathan C.; Ji, Pengfei; Lin, Zekai

2017-01-01

We report here the synthesis of a robust and highly porous Fe-phenanthroline-based metal–organic framework (MOF) and its application in catalyzing challenging inter- and intramolecular C–H amination reactions. For the intermolecular amination reactions, a FeBr 2-metalated MOF selectively functionalized secondary benzylic and allylic C–H bonds. The intramolecular amination reactions utilizing organic azides as the nitrene source required the reduction of the FeBr 2-metalated MOF with NaBHEt 3to generate the active catalyst. For both reactions, Fe or Zr leaching was less than 0.1%, and MOFs could be recycled and reused with no loss in catalytic activity. Furthermore, MOF catalysts were significantly moremore » active than the corresponding homogeneous analogs. This work demonstrates the great potential of MOFs in generating highly active, recyclable, and reusable earth abundant metal catalysts for challenging organic transformations.« less

UV-vis, IR and 1H NMR spectroscopic studies of some mono- and bis-azo-compounds based on 2,7-dihydroxynaphthalene and aniline derivatives

NASA Astrophysics Data System (ADS)

Issa, Raafat M.; Fayed, Tarek A.; Awad, Mohammed K.; El-Kony, Sanaa M.

2005-12-01

The absorption spectra of mono- and bis-azo-derivatives obtained by coupling the diazonium salts of aromatic amines and 2,7-dihydroxynaphthalene have been studied in six organic solvents. The different absorption bands have been assigned and the effect of solvents on the charge transfer band is also discussed. The diagnostic IR spectral bands and 1H NMR signals are assigned and discussed in relation to molecular structure. Also, semi-empirical molecular orbital calculations using the atom superposition and electron delocalization molecular orbital (ASED-MO) theory have been performed to investigate the molecular and electronic structures of these compounds. According to these calculations, an intramolecular hydrogen bonding is essential for stabilization of such molecules.

Correlations between the 1H NMR chemical shieldings and the pKa values of organic acids and amines.

PubMed

Lu, Juanfeng; Lu, Tingting; Zhao, Xinyun; Chen, Xi; Zhan, Chang-Guo

2018-06-01

The acid dissociation constants and 1 H NMR chemical shieldings of organic compounds are important properties that have attracted much research interest. However, few studies have explored the relationship between these two properties. In this work, we theoretically studied the NMR chemical shifts of a series of carboxylic acids and amines in the gas phase and in aqueous solution. It was found that the negative logarithms of the experimental acid dissociation constants (i.e., the pK a values) of the organic acids and amines in aqueous solution correlate almost linearly with the corresponding calculated NMR chemical shieldings. Key factors that affect the theoretically predicted pK a values are discussed in this paper. The present work provides a new way to predict the pK a values of organic/biochemical compounds. Graphical abstract The chemical shielding values of organic acids and amines correlate near linearly with their corresponding pK a values.

21 CFR 74.203 - FD&C Green No. 3.

Code of Federal Regulations, 2011 CFR

2011-04-01

...-aminobenzenesulfonic acid) to sodium 5-amino-2-formylbenzenesulfonate. This amine is diazotized and the resulting...-formylbenzenesulfonic acids, sodium salts, not more than 0.5 percent. Sum of 3- and 4-[[ethyl(4-sulfophenyl)amino]methyl... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR...

21 CFR 74.203 - FD&C Green No. 3.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-aminobenzenesulfonic acid) to sodium 5-amino-2-formylbenzenesulfonate. This amine is diazotized and the resulting...-formylbenzenesulfonic acids, sodium salts, not more than 0.5 percent. Sum of 3- and 4-[[ethyl(4-sulfophenyl)amino]methyl... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR...

40 CFR Appendix I to Part 192 - Listed Constituents

Code of Federal Regulations, 2012 CFR

2012-07-01

... (Propanedinitrile) Melphalan (L-Phenylalanine, 4-[bis(2-chloroethyl)aminol]-) Mercury and compounds, N.O.S. Mercury...) Amitrole (lH-1,2,4-Triazol-3-amine) Ammonium vanadate (Vanadic acid, ammonium salt) Aniline (Benzenamine...[N,N-dimethyl-]) Azaserine (L-Serine, diazoacetate (ester)) Barium and compounds, N.O.S. Barium...

40 CFR Appendix I to Part 192 - Listed Constituents

Code of Federal Regulations, 2014 CFR

2014-07-01

... (Propanedinitrile) Melphalan (L-Phenylalanine, 4-[bis(2-chloroethyl)aminol]-) Mercury and compounds, N.O.S. Mercury...) Amitrole (lH-1,2,4-Triazol-3-amine) Ammonium vanadate (Vanadic acid, ammonium salt) Aniline (Benzenamine...[N,N-dimethyl-]) Azaserine (L-Serine, diazoacetate (ester)) Barium and compounds, N.O.S. Barium...

40 CFR Appendix I to Part 192 - Listed Constituents

Code of Federal Regulations, 2013 CFR

2013-07-01

... (Propanedinitrile) Melphalan (L-Phenylalanine, 4-[bis(2-chloroethyl)aminol]-) Mercury and compounds, N.O.S. Mercury...) Amitrole (lH-1,2,4-Triazol-3-amine) Ammonium vanadate (Vanadic acid, ammonium salt) Aniline (Benzenamine...[N,N-dimethyl-]) Azaserine (L-Serine, diazoacetate (ester)) Barium and compounds, N.O.S. Barium...

Results of Research in the Field of Alkylphenol Additives

DTIC Science & Technology

The preparation of Ba and Ca salts of alkylphenols and bis(2- hydroxyphenylalkyl) sulfides are discussed along with the condensation products of... alkylphenols with HCHO or HCHO and urea, an amine or NH3 as well as the dithiophosphates of the latter. The properties and performance of lubricating oils

Biogenic amines in fish: roles in intoxication, spoilage, and nitrosamine formation--a review.

PubMed

Al Bulushi, Ismail; Poole, Susan; Deeth, Hilton C; Dykes, Gary A

2009-04-01

Biogenic amines are non-volatile amines formed by decarboxylation of amino acids. Although many biogenic amines have been found in fish, only histamine, cadaverine, and putrescine have been found to be significant in fish safety and quality determination. Despite a widely reported association between histamine and scombroid food poisoning, histamine alone appears to be insufficient to cause food toxicity. Putrescine and cadaverine have been suggested to potentiate histamine toxicity. With respect to spoilage on the other hand, only cadaverine has been found to be a useful index of the initial stage of fish decomposition. The relationship between biogenic amines, sensory evaluation, and trimethylamine during spoilage are influenced by bacterial composition and free amino acid content. A mesophilic bacterial count of log 6-7 cfu/g has been found to be associated with 5 mg histamine/100 g fish, the Food and Drug Administration (FDA) maximum allowable histamine level. In vitro studies have shown the involvement of cadaverine and putrescine in the formation of nitrosamines, nitrosopiperidine (NPIP), and nitrosopyrrolidine (NPYR), respectively. In addition, impure salt, high temperature, and low pH enhance nitrosamine formation, whereas pure sodium chloride inhibits their formation. Understanding the relationships between biogenic amines and their involvement in the formation of nitrosamines could explain the mechanism of scombroid poisoning and assure the safety of many fish products.

Electrospray ionization tandem mass spectrometry of ammonium cationized polyethers.

PubMed

Nasioudis, Andreas; Heeren, Ron M A; van Doormalen, Irene; de Wijs-Rot, Nicolette; van den Brink, Oscar F

2011-05-01

Quaternary ammonium salts (Quats) and amines are known to facilitate the MS analysis of high molar mass polyethers by forming low charge state adduct ions. The formation, stability, and behavior upon collision-induced dissociation (CID) of adduct ions of polyethers with a variety of Quats and amines were studied by electrospray ionization quadrupole time-of-flight, quadrupole ion trap, and linear ion trap tandem mass spectrometry (MS/MS). The linear ion trap instrument was part of an Orbitrap hybrid mass spectrometer that allowed accurate mass MS/MS measurements. The Quats and amines studied were of different degree of substitution, structure, and size. The stability of the adduct ions was related to the structure of the cation, especially the amine's degree of substitution. CID of singly/doubly charged primary and tertiary ammonium cationized polymers resulted in the neutral loss of the amine followed by fragmentation of the protonated product ions. The latter reveals information about the monomer unit, polymer sequence, and endgroup structure. In addition, the detection of product ions retaining the ammonium ion was observed. The predominant process in the CID of singly charged quaternary ammonium cationized polymers was cation detachment, whereas their doubly charged adduct ions provided the same information as the primary and tertiary ammonium cationized adduct ions. This study shows the potential of specific amines as tools for the structural elucidation of high molar mass polyethers. © American Society for Mass Spectrometry, 2011

Impacts of crystal metal on secondary aliphatic amine aerosol formation during dust storm episodes in Beijing

NASA Astrophysics Data System (ADS)

Liu, Qingyang; Bei, Yiling

2016-03-01

Trimethylamine (TMA) enters the atmosphere from a variety of sources and is a ubiquitous atmospheric organic base. The atmospheric reaction mechanism of TMA with key atmospheric oxidants is important to predict its distribution and environmental behavior in the particle phase. While previous studies have extensively focused on the production of particle amine salts (i.e. trimethylamine-N-oxide (TMAO)) using chamber experiments, the atmospheric behavior of TMAO in the environment is still poorly understood. Ambient fine particulate matter (PM2.5) was collected at two sampling sites in Beijing from March 10 to May 10, 2012. We analyzed the samples for water-soluble ions, crystal metals, TMA, and TMAO. Water-soluble ions (e.g. SO42-, NO3- , NH4+), TMA, and TMAO were measured using ion chromatography, while crystal metal (e.g. Al, Fe, Mn) in PM2.5 was quantified by inductively coupled plasma mass spectrometry (ICP-MS). Two dust storms (DS) occurred during the sampling period on March 28 and April 28. Mineral dust impacted PM2.5 mass and composition greatly during dust storm days, as it contributed approximately 1.2-4.0 times greater on dust storm days versus non-dust storm days. We found TMAO concentrations were highly associated with aluminum in PM2.5. Further, we applied the density functional theory (DFT) method to confirm that aluminum plays a catalytic effect in the reaction of TMA with ozone (O3). Our work improves understanding of the effect of crystal metals on secondary aliphatic amine aerosol formation in the atmosphere.

Cellular Membrane Phospholipids Act as a Depository for Quaternary Amine containing Drugs thus competing with the Acetylcholine / Nicotinic Receptor

PubMed Central

Barbacci, Damon; Jackson, Shelley N.; Muller, Ludovic; Egan, Thomas; Lewis, Ernest K.; Schultz, J. Albert; Woods, Amina S.

2014-01-01

We previously demonstrated that ammonium- or guanidinium- phosphate interactions are key to forming non-covalent complexes (NCXs) through salt bridge formation with G-protein coupled receptors (GPCR), which are immersed in the cell membrane's lipids. The present work highlights MALDI ion mobility coupled to orthogonal time-of-flight mass spectrometry (MALDI IM oTOF MS) as a method to determine qualitative and relative quantitative affinity of drugs to form NCXs with targeted GPCRs' epitopes in a model system using, bis-quaternary amine based drugs, α- and β- subunit epitopes of the nicotinic acetylcholine receptor' (nAChR) and phospholipids. Bis-quaternary amines proved to have a strong affinity for all nAChR epitopes and negatively charged phospholipids, even in the presence of the physiological neurotransmitter acetylcholine. Ion mobility baseline separated isobaric phosphatidyl ethanolamine and a matrix cluster, providing an accurate estimate for phospholipid counts. Overall this technique is a powerful method for screening drugs' interactions with targeted lipids and protein respectively containing quaternary amines and guanidinium moieties. PMID:22506649

Regeneration of 2-amino-2-methyl-1-propanol used for carbon dioxide absorption.

PubMed

Zhang, Pei; Shi, Yao; Wei, Jianwen; Zhao, Wei; Ye, Qing

2008-01-01

To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1-propranol (AMP) was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regenerationruns descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA).

SEDIMENT-ASSOCIATED REACTIONS OF AROMATIC AMINES. 2. QSAR DEVELOPMENT

EPA Science Inventory

The fate of aromatic amines in soils and sediments is dominated by irreversible binding through nucleophilic addition and oxidative radical coupling. Despite the common occurrence of the aromatic amine functional group in organic chemicals, the molecular properties useful for pr...

Method of stripping metals from organic solvents

DOEpatents

Todd, Terry A [Aberdeen, ID; Law, Jack D [Pocatello, ID; Herbst, R Scott [Idaho Falls, ID; Romanovskiy, Valeriy N [St. Petersburg, RU; Smirnov, Igor V [St.-Petersburg, RU; Babain, Vasily A [St-Petersburg, RU; Esimantovski, Vyatcheslav M [St-Petersburg, RU

2009-02-24

A new method to strip metals from organic solvents in a manner that allows for the recycle of the stripping agent. The method utilizes carbonate solutions of organic amines with complexants, in low concentrations, to strip metals from organic solvents. The method allows for the distillation and reuse of organic amines. The concentrated metal/complexant fraction from distillation is more amenable to immobilization than solutions resulting from current practice.

Back-extraction of trace elements from organometallic-halide extracts for determination by flameless atomic absorption spectrometry

USGS Publications Warehouse

Clark, J.R.; Viets, J.G.

1981-01-01

The Methyl isobutyl ketone-Amine synerGistic Iodkte Complex (MAGIC) extraction system offers the advantage that a large number of trace elements can be rapidly determined with a single sample preparation procedure. However, many of the elements extracted by the MAGIC system form volatile organometallic halide salts when the organic extract is heated in the graphite furnace. High concentrations of some elements such as Cu and Zn extracted by the system from anomalous geological samples produce serious interferences when certain other elements are determined by flameless atomic absorption. Stripping systems have been developed using solutions of HNO3, H2SO4, and CH3COOH individually or combined with H2O2 in order to circumvent these problems. With these systems most of the elements in the organic extract can be sequentially stripped into an aqueous phase. Organometallic volatilization and the most serious interelement interferences, therefore, can be eliminated by stripping with various combinations of reagents in a series of steps.

Development and validation of an LC-MS/MS method for the determination of biogenic amines in wines and beers.

PubMed

Nalazek-Rudnicka, Katarzyna; Wasik, Andrzej

2017-01-01

Biogenic amines are group of organic, basic, nitrogenous compounds that naturally occur in plant, microorganism, and animal organisms. Biogenic amines are mainly produced through decarboxylation of amino acids. They are formed during manufacturing of some kind of food and beverages such as cheese, wine, or beer. Histamine, cadaverine, agmatine, tyramine, putrescine, and β -phenylethylamine are the most common biogenic amines found in wines and beers. This group of compounds can be toxic at high concentrations; therefore, their control is very important. Analysis of biogenic amines in alcoholic drinks (beers and wines) was carried out by HPLC-MS/MS after their derivatization with p -toluenesulfonyl chloride (tosyl chloride). The developed method has been applied for analysis of seventeen biogenic amines in twenty-eight samples of lager beers and in twelve samples of different homemade wines (white grape, red grape, strawberry, chokeberry, black currant, plum, apple, raspberry, and quince). The developed method is sensitive and repeatable for majority of the analytes. It is versatile and can be used for the determination of biogenic amines in various alcoholic beverages.

Loading and release of amine drugs by ion-exchange fibers: role of amine type.

PubMed

Gao, Yanan; Liu, Hongzhuo; Yuan, Jing; Yang, Yang; Che, Xin; Hou, Yanlong; Li, Sanming

2014-04-01

With more production and application of ion-exchange fibers (IEFs), it becomes necessary to understand the interaction between IEFs and amine compounds, an important group of organic drugs and structural components of large organic molecules in biological systems. However, so far few experimental studies have been conducted to systematically investigate the exchanging mechanism of amine compounds to IEFs. Therefore, 15 amine drugs were selected to investigate the effect of amine type on the loading and release of them from the related IEFs. Loading affinity of these drugs by IEFs decreased in the order of secondary, tertiary, and primary. The following items: basicity, aromaticity, molar volume, rotatability, and so on, were emphatically discussed to address the underlying mechanism of drug loading and releasing extent and rate of IEFs. It was evident that strong alkaline drugs strengthened the ionic bond between the amine groups and IEFs, and thus the loading affinity. These results will advance the understanding of the exchanging behavior of IEFs in the drug delivery system. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Synthesis and characterization of silver nanoparticles from (bis)alkylamine silver carboxylate precursors

NASA Astrophysics Data System (ADS)

Uznanski, Pawel; Zakrzewska, Joanna; Favier, Frederic; Kazmierski, Slawomir; Bryszewska, Ewa

2017-03-01

A comparative study of amine and silver carboxylate adducts [R1COOAg-2(R2NH2)] (R1 = 1, 7, 11; R2 = 8, 12) as a key intermediate in NPs synthesis is carried out via differential scanning calorimetry, solid-state FT-infrared spectroscopy, 13C CP MAS NMR, powder X-ray diffraction and X-ray photoelectron spectroscopy, and various solution NMR spectroscopies (1H and 13C NMR, pulsed field gradient spin-echo NMR, and ROESY). It is proposed that carboxyl moieties in the presence of amine ligands are bound to silver ions via chelating bidentate type of coordination as opposed to bridging bidentate coordination of pure silver carboxylates resulting from the formation of dimeric units. All complexes are packed as lamellar bilayer structures. Silver carboxylate/amine complexes show one first-order melting transition. The evidence presented in this study shows that phase behavior of monovalent metal carboxylates are controlled, mainly, by head group bonding. In solution, insoluble silver salt is stabilized by amine molecules which exist in dynamic equilibrium. Using (bis)amine-silver carboxylate complex as precursor, silver nanoparticles were fabricated. During high-temperature thermolysis, the (bis)amine-carboxylate adduct decomposes to produce silver nanoparticles of small size. NPs are stabilized by strongly interacting carboxylate and trace amounts of amine derived from the silver precursor interacting with carboxylic acid. A corresponding aliphatic amide obtained from silver precursor at high-temperature reaction conditions is not taking part in the stabilization. Combining NMR techniques with FTIR, it was possible to follow an original stabilization mechanism.

Refractory Organic Compounds in Enceladus' Ice Grains and Hydrothermal Activity

NASA Astrophysics Data System (ADS)

Postberg, F.; Khawaja, N.; Hsu, H. W.; Sekine, Y.; Shibuya, T.

2015-12-01

Cassini's Cosmic Dust Analyzer (CDA) generates time-of-flight mass spectra of individual grains impinging on the instruments target-plate. Following the analysis of salt rich ice grains emitted by Enceladus that indicated a salt-water ocean in contact with the moon's rocky core [1,2] a recent CDA analysis of nano-phase silica particles pointed at hydrothermal activity at the moon's rock/water interface [3]. The results imply temperatures above 80 - 90°C and alkaline pH values around 10 reminiscent of alkaline hydrothermal vents on Earth like the Lost City Hydrothermal Field. In this context the compositional analysis of organic components in CDA mass spectra of the ejected ice grains is of particular relevance. A multitude of volatile organic species has already been identified in the gas component of the plume [4]. As expected, we find more complex organic molecules in ice grains than in the gas indicating aromatic species, amines, and carbonyl group species. The composition of organic-bearing ice grains displays a great diversity indicating a variety of different organic species in varying concentrations. Recent spatially resolved CDA in situ measurements inside Enceladus' plume indicate that these organic compounds are especially frequent in 'young' ice grains that have just been ejected by high velocity jets. We investigate the implications of our findings with respect to ice grain formation at the water surface and inside the icy vents. We constrain the generation of organic compounds at the rock/water interface in the light of hydrothermal activity and the potential for the formation of life precursor molecules in Enceladus' ocean. Ref:[1] Postberg et al., Nature 459, 1098-1101 (2009). [2] Postberg et al., Nature 474, 620-622 (2011). [3]. Hsu, Postberg, Sekine et al., Nature, 519, 207-210 (2015). [4] Waite et al., Nature 460, 487-490 (2009).

Technological Factors Affecting Biogenic Amine Content in Foods: A Review

PubMed Central

Gardini, Fausto; Özogul, Yesim; Suzzi, Giovanna; Tabanelli, Giulia; Özogul, Fatih

2016-01-01

Biogenic amines (BAs) are molecules, which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. The importance of preventing the excessive accumulation of BAs in foods is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BAs accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting BA content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity, and other BAs), environmental factors influencing BA formation (temperature, salt concentration, and pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolizing BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed. PMID:27570519

Supercritical fluid chromatographic resolution of water soluble isomeric carboxyl/amine terminated peptides facilitated via mobile phase water and ion pair formation.

PubMed

Patel, M A; Riley, F; Ashraf-Khorassani, M; Taylor, L T

2012-04-13

Both analytical scale and preparative scale packed column supercritical fluid chromatography (SFC) have found widespread applicability for chiral separations of multiple polar pharmaceutical candidates. However, SFC is rapidly becoming an achiral technique. More specifically, ion pair SFC is finding greater utility for separation of ionic analytes such as amine salts and organic sulfonates. The key to this success is, in part, the incorporation of additives such as trifluoroacetic acid and ammonium acetate into the mobile phase in association with a wide variety of both bonded silica stationary phases and high purity bare silica. Ion pairing SFC coupled with evaporative light scattering detection and mass spectrometric detection is presented here for the separation of water soluble, uncapped, isomeric peptide pairs that differ in amino acid arrangement. The separation is best achieved on either diol-bonded silica or bare silica with 1-5% (w/w) water as a significant ingredient in the mobile phase. Nitrogenous stationary phases such as 2-ethylpyridine, which had been very successful for the separation of capped peptides failed to yield the desired separation regardless of the mobile phase composition. A HILIC type retention mechanism is postulated for the separation of both isomeric uncapped peptide pairs. Copyright © 2012 Elsevier B.V. All rights reserved.

Modeling of a complex, polar system with a modified Soave-Redlich-Kwong equation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sturnfield, E.A.; Matherne, J.L.

1988-01-01

It is computationally feasible to use a simple equation of state (like a Redlich-Kwong) to calculate liquid fugacity but the simpler equations work well only for moderately non-ideal systems. More complex equations (like Ghemling-Lui-Prausnitz) predict system behavior more accurately but are much more complicated to use and can require fitting many parameters to data. This paper illustrates success in using a modified Redlich-Kwong to model a complex system including water, hydrogen, sub and supercritical ammonia, and amines. The binary interaction parameter ({Kappa}/sub ij/) of the Soave-Redlich-Kwong equation has been modified to be both asymmetric and temperature dependent. Further, the aimore » constant was determined by fitting vapor pressure data. Predicted model results are compared to literature (example 1) or plant data (examples 2-4) for four systems: 1. The ammonia-water binary over a wide range of pressure and temperature including ammonia above its critical. 2. A multicomponent Vapor-Liquid equilibrium flash tank and condenser containg hydrogen, amonia, water, and other heavier compounds. 3. A multicomponent vapor-liquid equilibrium flash tank containing water, heavier mines, and the amine salts. 4. A Liquid-Liquid-Vapor equilibrium decanter system containing water, ammonia, and an organic chloride.« less

Technological Factors Affecting Biogenic Amine Content in Foods: A Review.

PubMed

Gardini, Fausto; Özogul, Yesim; Suzzi, Giovanna; Tabanelli, Giulia; Özogul, Fatih

2016-01-01

Biogenic amines (BAs) are molecules, which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. The importance of preventing the excessive accumulation of BAs in foods is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BAs accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting BA content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity, and other BAs), environmental factors influencing BA formation (temperature, salt concentration, and pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolizing BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed.

Foods and risk of bladder cancer: a case-control study in Uruguay.

PubMed

Balbi, J C; Larrinaga, M T; De Stefani, E; Mendilaharsu, M; Ronco, A L; Boffetta, P; Brennan, P

2001-10-01

A case-control study on 144 cases of transitional cell bladder carcinoma and 576 hospitalized controls was conducted in Montevideo, Uruguay. Barbecued meat, salted meat and fried eggs were associated with significant increased risks of bladder cancer (odds ratio (OR) for high intake of salted meat 4.04, 95% confidence interval (CI) 2.24-7.27). On the other hand, all fruits, cooked vegetables, potatoes and cheese were associated with inverse associations (OR for high consumption of potatoes 0.38, 95% CI 0.23-0.64). The associations with salted and barbecued meat suggest that the way of preserving or cooking meat play a role in bladder carcinogenesis. More precisely, N-nitroso compounds and heterocyclic amines could be involved in this process.

Aquatic toxicity and biodegradability of advanced cationic surfactant APA-22 compatible with the aquatic environment.

PubMed

Yamane, Masayuki; Toyo, Takamasa; Inoue, Katsuhisa; Sakai, Takaya; Kaneko, Youhei; Nishiyama, Naohiro

2008-01-01

Cationic surfactant is a chemical substance used in hair conditioner, fabric softener and other household products. By investigating the relationship between the aquatic toxicity and the chemical structures of two types of mono alkyl cationic surfactants, alkyl trimethylammonium salts and alkyl dimethylamine salts, we have found that the C22 alkyl chain length is effective to reduce the toxicity. Besides, we have recognized that the amidopropyl functional group contributes to the enhanced biodegradability by investigating the biodegradation trend of (alkylamidopropyl)dimethylamine salt (alkyl chain length: C18). Based on these findings, we have developed mono alkyl cationic surfactant called APA-22, N-[3-(dimethylamino)propyl]docosanamide salt. APA-22 is formed by the C22 alkyl chain, amidopropyl functional group and di-methyltertiary amine group. We evaluated the aerobic and anaerobic biodegradability of APA-22 by two standard methods (OECD Test Guideline 301B and ECETOC technical document No.28) and found that this substance was degraded rapidly in both conditions. The toxicity to algae, invertebrate and fish of this substance are evaluated by using OECD Test Guideline 201, 202 and 203, respectively. All acute toxicity values are >1 mg/L, which indicates that environmental toxicity of this substance is relatively less toxic to aquatic organism. In addition, we estimated the biodegradation pathway of APA-22 and observed the complete disappearance of APA-22 and its intermediates during the test periods. Based on the environmental data provided above, we concluded that APA22 is more compatible with the aquatic environment compared to other cationic surfactants with mono long alkyl chain.

Polymide gas separation membranes

DOEpatents

Ding, Yong; Bikson, Benjamin; Nelson, Joyce Katz

2004-09-14

Soluble polyamic acid salt (PAAS) precursors comprised of tertiary and quaternary amines, ammonium cations, sulfonium cations, or phosphonium cations, are prepared and fabricated into membranes that are subsequently imidized and converted into rigid-rod polyimide articles, such as membranes with desirable gas separation properties. A method of enhancing solubility of PAAS polymers in alcohols is also disclosed.

Water free proton conducting membranes based on poly-4-vinylpyridinebisulfate for fuel cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram R. (Inventor); Yen, Shiao-Pin S. (Inventor)

2007-01-01

Disclosed are methods for forming a water-free electrolyte membrane useful in fuel cells. Also provided is a water-free electrolyte membrane comprising a quaternized amine salt including poly-4-vinylpyridinebisulfate, a poly-4-vinylpyridinebisulfate silica composite, and a combination thereof and a fuel cell comprising the membrane.

40 CFR 721.1675 - Disulfonic acid rosin amine salt of a benzidine derivative (generic name).

Code of Federal Regulations, 2011 CFR

2011-07-01

... benzidine derivative (generic name). 721.1675 Section 721.1675 Protection of Environment ENVIRONMENTAL... benzidine derivative (generic name). (a) Chemical substance and significant new uses subject to reporting... derivative (PMN P-87-1337) is subject to reporting under this section for the significant new uses described...

Properties of amylose complexes with hexadecyl amine and its hydrochloride salt prepared by steam jet cooking

USDA-ARS?s Scientific Manuscript database

Steam jet cooking of starch is an effective, commercially scalable method of preparing amylose for complexing with a variety of ligands. Previous work has shown that dispersions of amylose complexes prepared with fatty acids (such as palmitic) formed a variety of spherulites when cooled under diffe...

40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl sulfates...

40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl sulfates...

40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl sulfates...

40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl sulfates...

40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl sulfates...

QUANTIFICATION OF 2,4-D ON SOLID-PHASE EXPOSURE SAMPLING MEDIA BY LC/MS/MS

EPA Science Inventory

Three types of solid phase chemical exposure sampling media: cellulose, polyurethane foam (PUF) and XAD-2, were analyzed for 2,4-D and the amine salts of 2,4-D. Individual samples were extracted into acidified methanol and the extracts were analyzed via LC/MS/MS using electrospra...

Surface characterization in composite and titanium bonding: Carbon fiber surface treatments for improved adhesion to thermoplastic polymers

NASA Technical Reports Server (NTRS)

Devilbiss, T. A.; Wightman, J. P.

1987-01-01

The effect of anodization in NaOH, H2SO4, and amine salts on the surface chemistry of carbon fibers was examined by X-ray photoelectron spectroscopy (XPS). The surfaces of carbon fibers after anodization in NaOH and H2SO4 were examined by scanning transmission electron microscopy (STEM), angular dependent XPS, UV absorption spectroscopy of the anodization bath, secondary ion mass spectrometry, and polar/dispersive surface energy analysis. Hercules AS-4, Dexter Hysol XAS, and Union Carbide T-300 fibers were examined by STEM, angular dependent XPS, and breaking strength measurement before and after commercial surface treatment. Oxygen and nitrogen were added to the fiber surfaces by anodization in amine salts. Analysis of the plasmon peak in the carbon 1s signal indicated that H2SO4 anodization affected the morphological structure of the carbon fiber surface. The work of adhesion of carbon fibers to thermoplastic resins was calculated using the geometric mean relationship. A correlation was observed between the dispersive component of the work of adhesion and the interfacial adhesion.

Quantification of amine functional groups and their influence on OM/OC in the IMPROVE network

NASA Astrophysics Data System (ADS)

Kamruzzaman, Mohammed; Takahama, Satoshi; Dillner, Ann M.

2018-01-01

Recently, we developed a method using FT-IR spectroscopy coupled with partial least squares (PLS) regression to measure the four most abundant organic functional groups, aliphatic C-H, alcohol OH, carboxylic acid OH and carbonyl C=O, in atmospheric particulate matter. These functional groups are summed to estimate organic matter (OM) while the carbon from the functional groups is summed to estimate organic carbon (OC). With this method, OM and OM/OC can be estimated for each sample rather than relying on one assumed value to convert OC measurements to OM. This study continues the development of the FT-IR and PLS method for estimating OM and OM/OC by including the amine functional group. Amines are ubiquitous in the atmosphere and come from motor vehicle exhaust, animal husbandry, biomass burning, and vegetation among other sources. In this study, calibration standards for amines are produced by aerosolizing individual amine compounds and collecting them on PTFE filters using an IMPROVE sampler, thereby mimicking the filter media and collection geometry of ambient standards. The moles of amine functional group on each standard and a narrow range of amine-specific wavenumbers in the FT-IR spectra (wavenumber range 1 550-1 500 cm-1) are used to develop a PLS calibration model. The PLS model is validated using three methods: prediction of a set of laboratory standards not included in the model, a peak height analysis and a PLS model with a broader wavenumber range. The model is then applied to the ambient samples collected throughout 2013 from 16 IMPROVE sites in the USA. Urban sites have higher amine concentrations than most rural sites, but amine functional groups account for a lower fraction of OM at urban sites. Amine concentrations, contributions to OM and seasonality vary by site and sample. Amine has a small impact on the annual average OM/OC for urban sites, but for some rural sites including amine in the OM/OC calculations increased OM/OC by 0.1 or more.

RECOVERY OF URANIUM VALUES

DOEpatents

Brown, K.B.; Crouse, D.J. Jr.; Moore, J.G.

1959-03-10

A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine in the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected amine dissolved in a nonpolar water-immiscible organic solvent such as kerosene. The uranium which is substantially completely exiracted by the organic phase may be stripped therefrom by waters and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

Molecular Blends of Methylated-Poly(ethylenimine) and Amorphous Porous Organic Cages for SO 2 Adsorption

DOE PAGES

Zhu, Guanghui; Carrillo, Jan-Michael Y.; Sujan, Achintya; ...

2018-05-30

Porous organic cages (POCs) are emerging porous materials that exhibit intriguing properties in the areas of self-assembly, host-guest interaction, and solution processability. Here in this work, we explore the applicability of POCs as molecular porous supports for polymeric amines. We find that primary amines in poly(ethylenimine) (PEI) can undergo metathesis with the imine bonds present in POCs, resulting in non-porous products. This problem can be overcome by transforming the primary amines in PEI to tertiary amines via methylation. The methylated PEI (mPEI) forms homogeneous composites with amorphous scrambled porous organic cages (ASPOCs) without undesired reactions or phase separation. The microscopicmore » structure of the composites is studied using molecular dynamics simulations. Finally, these composite materials are evaluated as adsorbents for low concentration SO2 (200 ppm) adsorption and show good thermal and cyclic stability.« less

Molecular Blends of Methylated-Poly(ethylenimine) and Amorphous Porous Organic Cages for SO 2 Adsorption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Guanghui; Carrillo, Jan-Michael Y.; Sujan, Achintya

Porous organic cages (POCs) are emerging porous materials that exhibit intriguing properties in the areas of self-assembly, host-guest interaction, and solution processability. Here in this work, we explore the applicability of POCs as molecular porous supports for polymeric amines. We find that primary amines in poly(ethylenimine) (PEI) can undergo metathesis with the imine bonds present in POCs, resulting in non-porous products. This problem can be overcome by transforming the primary amines in PEI to tertiary amines via methylation. The methylated PEI (mPEI) forms homogeneous composites with amorphous scrambled porous organic cages (ASPOCs) without undesired reactions or phase separation. The microscopicmore » structure of the composites is studied using molecular dynamics simulations. Finally, these composite materials are evaluated as adsorbents for low concentration SO2 (200 ppm) adsorption and show good thermal and cyclic stability.« less

Absorption and desorption of SO2 in aqueous solutions of diamine-based molten salts.

PubMed

Lim, Seung Rok; Hwang, Junhyeok; Kim, Chang Soo; Park, Ho Seok; Cheong, Minserk; Kim, Hoon Sik; Lee, Hyunjoo

2015-05-30

SO2 absorption and desorption behaviors were investigated in aqueous solutions of diamine-derived molten salts with a tertiary amine group on the cation and a chloride anion, including butyl-(2-dimethylaminoethyl)-dimethylammonium chloride ([BTMEDA]Cl, pKb=8.2), 1-butyl-1,4-dimethylpiperazinium chloride ([BDMP]Cl, pKb=9.8), and 1-butyl-4-aza-1-azoniabicyclo[2,2,2]octane chloride ([BDABCO]Cl, pKb=11.1). The SO2 absorption and desorption performance of the molten salt were greatly affected by the basicity of the molten salt. Spectroscopic, X-ray crystallographic, and computational results for the interactions of SO2 with molten salts suggest that two types of SO2-containg species could be generated depending on the basicity of the unquaternized amino group: a dicationic species comprising two different anions, HSO3(-) and Cl(-), and a monocationic species bearing Cl(-) interacting with neutral H2SO3. Copyright © 2015 Elsevier B.V. All rights reserved.

Temperature- and pH-dependent aqueous-phase kinetics of the reactions of glyoxal and methylglyoxal with atmospheric amines and ammonium sulfate

NASA Astrophysics Data System (ADS)

Sedehi, Nahzaneen; Takano, Hiromi; Blasic, Vanessa A.; Sullivan, Kristin A.; De Haan, David O.

2013-10-01

Reactions of glyoxal (Glx) and methylglyoxal (MG) with primary amines and ammonium salts may produce brown carbon and N-containing oligomers in aqueous aerosol. 1H NMR monitoring of reactant losses and product appearance in bulk aqueous reactions were used to derive rate constants and quantify competing reaction pathways as a function of pH and temperature. Glx + ammonium sulfate (AS) and amine reactions generate products containing C-N bonds, with rates depending directly on pH: rate = (70 ± 60) M-1 s-1fAld [Glx]totfAm [Am]tot, where fAld is the fraction of aldehyde with a dehydrated aldehyde functional group, and fAm is the fraction of amine or ammonia that is deprotonated at a given pH. MG + amine reactions generate mostly aldol condensation products and exhibit less pH dependence: rate = 10[(0.36 ± 0.06) × pH - (3.6 ± 0.3)] M-1 s-1fAld [MG]tot [Am]tot. Aldehyde + AS reactions are less temperature-dependent (Ea = 18 ± 8 kJ mol-1) than corresponding amine reactions (Ea = 50 ± 11 kJ mol-1). Using aerosol concentrations of [OH] = 10-12 M, [amine]tot = [AS] = 0.1 M, fGlx = 0.046 and fMG = 0.09, we estimate that OH radical reactions are normally the major aerosol-phase sink for both dicarbonyl compounds. However, reactions with AS and amines together can account for up to 12 and 45% of daytime aerosol-phase glyoxal and methylglyoxal reactivity, respectively, in marine aerosol at pH 5.5. Reactions with AS and amines become less important in acidic or non-marine aerosol, but may still be significant atmospheric sources of brown carbon, imidazoles, and nitrogen-containing oligomers.

Effect of bentonite modification on hardness and mechanical properties of natural rubber nanocomposites

NASA Astrophysics Data System (ADS)

Santiago, Denise Ester O.; Pajarito, Bryan B.; Mangaccat, Winna Faye F.; Tigue, Maelyn Rose M.; Tipton, Monica T.

2016-05-01

The effect of sodium activation, ion-exchange with tertiary amine salt, surface treatment with non-ionic surfactant, and wet grinding of bentonite on hardness and mechanical properties of natural rubber nanocomposites (NRN) was studied using full factorial design of experiment. Results of X-ray diffraction (XRD) show increase in basal spacing d of bentonite due to modification, while attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) confirm the organic modification of bentonite. Analysis of variance (ANOVA) shows that the main effect of surface treatment increases the hardness and decreases the tensile modulus of the NRN. The surface treatment and wet grinding of bentonite decrease the tensile stresses at 100, 200 and 300% strain of NRN. Sodium activation and ion-exchange negatively affect the compressive properties, while surface treatment significantly improves the compressive properties of NRN.

Covalent Binding of Aromatic Amines to Natural Organic Matter: Study of Reaction Mechanisms and Development of Remediation Schemes

EPA Science Inventory

Aromatic amines comprise an important class of environmental contaminants. Concern over their environmental fate arises from the toxic effects that certain aromatic amines exhibit toward microbial populations and reports that they can be toxic or carcinogenic to animals. Aromatic...

Mechanistic insights into the one-pot synthesis of propargylamines from terminal alkynes and amines in chlorinated solvents catalyzed by gold compounds and nanoparticles.

PubMed

Aguilar, David; Contel, Maria; Urriolabeitia, Esteban P

2010-08-09

Propargylamines can be obtained from secondary amines and terminal alkynes in chlorinated solvents by a three- and two-component synthesis catalyzed by gold compounds and nanoparticles (Au-NP) under mild conditions. The use of dichloromethane allows for the activation of two C-Cl bonds and a clean transfer of the methylene fragment to the final product. The scope of the reaction as well as the influence of different gold(III) cycloaurated complexes and salts has been investigated. The involvement of gold nanoparticles generated in situ in the process is discussed and a plausible reaction mechanism is proposed on the basis of the data obtained.

Iron-catalyzed synthesis of secondary amines: on the way to green reductive aminations.

PubMed

Stemmler, Tobias; Surkus, Annette-Enrika; Pohl, Marga-Martina; Junge, Kathrin; Beller, Matthias

2014-11-01

Amines represent important intermediates in chemical and biological processes. Herein, we describe the use of a nanostructured iron-based catalyst for the tandem reductive amination between nitroarenes and aldehydes using hydrogen as reductant. The nanostructured iron-catalyst is prepared by immobilization of an iron-phenanthroline complex onto a commercially available carbon support. In the reaction sequence a primary amine is formed in situ from the corresponding nitro compound. Reversible condensation with aldehydes forms the respective imines, which are finally reduced to the desired secondary amine. This synthesis of secondary amines is atom-economical and environmentally attractive using cheap and readily available organic compounds as starting materials. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Two-component gelator isomers with different combination of amine and acid: Helical/non-helical morphology and selective adsorption of dyes.

PubMed

Han, Xiaoyu; Liu, Jiahui; Zhao, Chaoyue; Zhang, Bao; Xu, Xiufang; Song, Jian

2018-09-01

Hydrogels induced by two-component gelator isomers based on the different amine/acid interactions were investigated. Scanning electron microscopy and atomic force microscopy images of the xerogel obtained from the two hydrogels revealed different assembly morphologies. While left-handed helical fibers were observed for the amine-acid based xerogel, acid-amine underwent self-assembly to afford smooth fibers. Fourier transform infrared spectroscopy, fluorescence, and X-ray diffraction measurements combined with density functional theory calculations suggested that the different self-assembly patterns of gelators resulted in opposite electric charges on the xerogel surfaces, in line with Zeta potential measurements. Based on these opposite charges resulting from their different self-assemblies, both xerogels demonstrated efficient dye adsorption abilities with different selectivities. Interestingly, the adsorption performance was not influenced by the salt in the dye solution. Furthermore, the xerogels still showed high dye adsorption efficiency after four cycles. These results provide a two-component hydrogel method for the purification of dye-polluted water systems, while also paving the way for future design of functionalized supramolecular self-assembly systems. Copyright © 2018 Elsevier Inc. All rights reserved.

A new route to prepare multiresponsive organogels from a block ionomer via charge-driven assembly.

PubMed

Zhang, Tao; Guo, Qipeng

2013-06-04

We report a novel route to prepare multiresponsive organogels through charge-driven assembly between a block ionomer and a diblock copolymer. The ionic complex aggregates to form spherical cores, which are connected by the middle block of the block ionomer to form gels. The organogels are responsive to acids, amines and salts.

Non-traditional Oxidants in Preparative Coordination Chemistry

NASA Astrophysics Data System (ADS)

Kukushkin, Vadim Yu; Kukushkin, Yurii N.

1986-10-01

The application of nitrosonium and arenediazonium salts, carbenium, silver(I), and mercury(II) ions, protic acids, and amine oxides as oxidants in preparative coordination chemistry is examined. Specific examples illustrate which problems in the field of the synthesis and reactions of coordination compounds can be solved with the aid of these oxidants. The bibliography includes 158 references.

The Petasis Reaction: Microscale Synthesis of a Tertiary Amine Antifungal Analog

ERIC Educational Resources Information Center

Koroluk, Katherine J.; Jackson, Derek A.; Dicks, Andrew P.

2012-01-01

Students prepare a tertiary amine antifungal analog in an upper-level undergraduate organic laboratory. A microscale Petasis reaction is performed to generate a liquid compound readily characterized via IR and proton NMR spectroscopy. The biological relevance of the product is highlighted, with the tertiary amine scaffold being an important…

Unusual reversal of enantioselectivity in the proline-mediated alpha-amination of aldehydes induced by tertiary amine additives.

PubMed

Blackmond, Donna G; Moran, Antonio; Hughes, Matthew; Armstrong, Alan

2010-06-09

An intriguing reversal in product enantioselectivity accompanied by a change in the kinetic profile is observed in the alpha-amination of aldehydes catalyzed by proline in the presence of organic bases. Implications for the prevailing stereochemical models for proline and related aminocatalytic transformations are discussed.

Determination of imidazoline and amido-amine type corrosion inhibitors in both crude oil and produced brine from oilfield production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matherly, R.M.; Jiao, J.; Blumer, D.J.

1995-12-01

The classical method for the determination of corrosion inhibitors in oilfield brines is the dye transfer method. Within this method are many variations which the analyst may use to determine the amount of corrosion inhibitor in either water or crude oil. These methods, however, suffer from many interferences which result in both false positive and negatives for corrosion inhibitor content. These methods essentially detect all amines as corrosion inhibitors. Improved high pressure liquid chromatography (HPLC) methods have been developed for the analysis of quaternary salt type corrosion inhibitors in brine waters, however, these methods do not appear to work inmore » crude oil or for other forms of corrosion inhibitors such as the imidazolines, and amido-amines. This paper presents a method for the quantitative analysis of the imidazoline and amido-amine type corrosion inhibitors in both oilfield water and crude oil samples by HPLC. The corrosion inhibitor of interest is first separated from the matrix on a small column, then derivatized to form a product which is both sensitive and selective on a fluorescence detector. Detection limits for imidazolines are around 0.2 mg/L, amides and amines are similar. The advantage of this procedure is it can be used to determine the amount of corrosion inhibitor in both oil and brine water phases as well as on solid surfaces.« less

In Vitro Evaluation of the Probiotic and Safety Properties of Bacteriocinogenic and Non-Bacteriocinogenic Lactic Acid Bacteria from the Intestines of Nile Tilapia and Common Carp for Their Use as Probiotics in Aquaculture.

PubMed

Kaktcham, Pierre Marie; Temgoua, Jules-Bocamdé; Zambou, François Ngoufack; Diaz-Ruiz, Gloria; Wacher, Carmen; Pérez-Chabela, María de Lourdes

2018-03-01

In this study, seven bacteriocinogenic and non-bacteriocinogenic LAB strains previously isolated from the intestines of Nile tilapia and common carp and that showed potent antibacterial activity against host-derived and non-host-derived fish pathogens were assayed for their probiotic and safety properties so as to select promising candidates for in vivo application as probiotic in aquaculture. All the strains were investigated for acid and bile tolerances, transit tolerance in simulated gastrointestinal conditions, for cell surface characteristics including hydrophobicity, co-aggregation and auto-aggregation, and for bile salt hydrolase activity. Moreover, haemolytic, gelatinase and biogenic amine-producing abilities were investigated for safety assessment. The strains were found to be tolerant at low pH (two strains at pH 2.0 and all the strains at pH 3.0). All of them could also survive in the presence of bile salts (0.3% oxgall) and in simulated gastric and intestinal juices conditions. Besides, three of them were found to harbour the gtf gene involved in pH and bile salt survival. The strains also showed remarkable cell surface characteristics, and 57.14% exhibited the ability to deconjugate bile salts. When assayed for their safety properties, the strains prove to be free from haemolytic activity, gelatinase activity and they could neither produce biogenic amines nor harbour the hdc gene. They did not also show antibiotic resistance, thus confirming to be safe for application as probiotics. Among them, Lactobacillus brevis 1BT and Lactobacillus plantarum 1KMT exhibited the best probiotic potentials, making them the most promising candidates.

Application of an amine functionalized biopolymer in the colonic delivery of glycyrrhizin: a design and in vivo efficacy study.

PubMed

Kumar De, Amit; Datta, Sriparna; Mukherjee, Arup

2013-01-01

In our current study, a newer amine functionalized guar gum derivative was studied for its efficacy in colonic drug delivery. Glycyrrhizic acid mono-ammonium salt was used as the model drug. Drug-loaded microparticles were formulated by ionic crosslinking using sodium tripolyphosphate. The Scanning Electron Microscopic study revealed spherical particles of sizes from 4.9 ± 3.8 μm to 6.9 ± 3.9 μm. The FT-IR studies presented a possible interaction between the drug and the polymer. The drug was encapsulated in amorphous form as observed from the powder X-Ray Diffraction studies. A cumulative drug release study was carried out in simulated gastric, intestinal, and colonic fluids. The cumulative drug release studies presented a burst release followed by a sustained release of the drug in simulated colonic fluid containing rat cecal contents. The drug-polymer ratio was optimised using a 3(2) factorial design by taking the amounts of glycyrrhizic acid (X1) and guar gum alkyl amine (X2) as the independant variables. The percent cumulative drug release at 240 mins (Q240), 720 mins (Q720), and at 1,440 mins (Q1440) were considered as the dependant variables. The efficacy of the optimized formulation was studied in a 2,4,6-trinitrobenzene sulfonic acid-induced rat colitis model. The tissue's nitric oxide, malondialdehyde, and myeloperoxidase activities were found to be much lower in the microparticle-treated group compared to free drug-treated group. The histology of the colonic tissue from the treated group of animals revealed almost no infiltration of inflammatory cells in the tissue for the microparticle-treated group of animals. The synthesized amine derivative of guar gum was found to be better in vitro with a better in vivo efficacy in the colonic delivery of glycyrrhizic acid monoammonium salt and can be considered as a newer modified biopolymer for colonic drug delivery.

Effect of wine addition on microbiological characteristics, volatile molecule profiles and biogenic amine contents in fermented sausages.

PubMed

Coloretti, Fabio; Tabanelli, Giulia; Chiavari, Cristiana; Lanciotti, Rosalba; Grazia, Luigi; Gardini, Fausto; Montanari, Chiara

2014-03-01

The aim was to evaluate the effect of wine addition during manufacturing of dry fermented sausages, in terms of safety aspects (biogenic amine accumulation), aroma profile and sensory characteristics. Three batches of salami were produced: without wine addition and with 7.5% or 15% (v/w) of white wine. The fermented sausages showed characteristics that can increase product diversification. Some of the sensory features (i.e. increased salty perception) can represent an important strategy because of the trend to reduce salt intake for health reasons. The presence of wine immediately reduced the pH and is a source of ethanol, which can have an inhibitory effect against undesirable microflora. The microbiological results observed regarding Enterobacteriaceae and enterococci were encouraging. The addition of wine did not negatively affect the ripening time or increase the presence of biogenic amines. The samples containing wine showed reduced concentrations of putrescine. Copyright © 2013 Elsevier Ltd. All rights reserved.

Zwitterionic-surfactant-stabilized palladium nanoparticles as catalysts in the hydrogen transfer reductive amination of benzaldehydes.

PubMed

Drinkel, Emma E; Campedelli, Roberta R; Manfredi, Alex M; Fiedler, Haidi D; Nome, Faruk

2014-03-21

Palladium nanoparticles (NPs) stabilized by a zwitterionic surfactant are revealed here to be good catalysts for the reductive amination of benzaldehydes using formate salts as hydrogen donors in aqueous isopropanol. In terms of environmental impact and economy, metallic NPs offer several advantages over homogeneous and traditional heterogeneous catalysts. NPs usually display greater activity due to the increased metal surface area and sometimes exhibit enhanced selectivity. Thus, it is possible to use very low loadings of expensive metal. The methodology eliminates the use of a hydrogen gas atmosphere or toxic or expensive reagents. A range of aromatic aldehydes were converted to benzylamines when reacted with primary and secondary amines in the presence of the Pd NPs, which also displayed good activity when supported on alumina. In every case, the Pd NPs could be easily recovered and reused up to three more times, and at the end of the process, the product was metal-free.

Simple diazonium chemistry to develop specific gene sensing platforms.

PubMed

Revenga-Parra, M; García-Mendiola, T; González-Costas, J; González-Romero, E; Marín, A García; Pau, J L; Pariente, F; Lorenzo, E

2014-02-27

A simple strategy for covalent immobilizing DNA sequences, based on the formation of stable diazonized conducting platforms, is described. The electrochemical reduction of 4-nitrobenzenediazonium salt onto screen-printed carbon electrodes (SPCE) in aqueous media gives rise to terminal grafted amino groups. The presence of primary aromatic amines allows the formation of diazonium cations capable to react with the amines present at the DNA capture probe. As a comparison a second strategy based on the binding of aminated DNA capture probes to the developed diazonized conducting platforms through a crosslinking agent was also employed. The resulting DNA sensing platforms were characterized by cyclic voltammetry, electrochemical impedance spectroscopy and spectroscopic ellipsometry. The hybridization event with the complementary sequence was detected using hexaamineruthenium (III) chloride as electrochemical indicator. Finally, they were applied to the analysis of a 145-bp sequence from the human gene MRP3, reaching a detection limit of 210 pg μL(-1). Copyright © 2014 Elsevier B.V. All rights reserved.

Water purification using organic salts

DOEpatents

Currier, Robert P.

2004-11-23

Water purification using organic salts. Feed water is mixed with at least one organic salt at a temperature sufficiently low to form organic salt hydrate crystals and brine. The crystals are separated from the brine, rinsed, and melted to form an aqueous solution of organic salt. Some of the water is removed from the aqueous organic salt solution. The purified water is collected, and the remaining more concentrated aqueous organic salt solution is reused.

Comparative metabolic and ionomic profiling of two cultivars of Stevia rebaudiana Bert. (Bertoni) grown under salinity stress.

PubMed

Debnath, Mousumi; Ashwath, Nanjappa; Hill, Camilla Beate; Callahan, Damien L; Dias, Daniel Anthony; Jayasinghe, Nirupama Samanmalie; Midmore, David James; Roessner, Ute

2018-05-10

This study provides a comprehensive investigation on the impact of increasing NaCl concentrations on hydroponically grown Stevia rebaudiana cultivars (Shoutian-2 and Fengtian). Growth parameters including plant height, biomass and physiological responses including osmotic potential were measured. In addition, the levels of steviol glycosides, elements and primary metabolites were measured and statistically evaluated. The cultivar Fengtian grew faster, accumulated less Na + and compatible organic solutes, and more K + in the leaves, as compared to the cv. Shoutian-2. Metabolite analysis identified 81 differentially accumulated metabolites, indicating an alteration in the metabolite phenotype of both cultivars upon exposure to salinity A general increase in many amino acids, amines, sugars and sugar phosphates with a concurrent decrease in most organic acids; including tricarboxylic acid (TCA) cycle intermediates, was observed. In the more salt tolerant cv. Fengtian, the levels of hexose phosphates and metabolites involved in cellular protection increased in response to salinity. These metabolites remained unchanged in the sensitive cv. Shoutian-2. Interestingly, salt treatment notably increased the rebaudioside A concentration by 53% while at the same time stevioside decreased by 38% in Fengtian which has important implications for controlling the relative amounts of reboudioside A and stevioside. The findings of this study leads to the conclusion that mild salinity stress can increase the yield of sweetener compounds, which is dependent on the cultivar and the level of salinity stress. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Synthesis and characterization of silver nanoparticles from (bis)alkylamine silver carboxylate precursors.

PubMed

Uznanski, Pawel; Zakrzewska, Joanna; Favier, Frederic; Kazmierski, Slawomir; Bryszewska, Ewa

2017-01-01

A comparative study of amine and silver carboxylate adducts [R 1 COOAg-2(R 2 NH 2 )] (R 1  = 1, 7, 11; R 2  = 8, 12) as a key intermediate in NPs synthesis is carried out via differential scanning calorimetry, solid-state FT-infrared spectroscopy, 13 C CP MAS NMR, powder X-ray diffraction and X-ray photoelectron spectroscopy, and various solution NMR spectroscopies ( 1 H and 13 C NMR, pulsed field gradient spin-echo NMR, and ROESY). It is proposed that carboxyl moieties in the presence of amine ligands are bound to silver ions via chelating bidentate type of coordination as opposed to bridging bidentate coordination of pure silver carboxylates resulting from the formation of dimeric units. All complexes are packed as lamellar bilayer structures. Silver carboxylate/amine complexes show one first-order melting transition. The evidence presented in this study shows that phase behavior of monovalent metal carboxylates are controlled, mainly, by head group bonding. In solution, insoluble silver salt is stabilized by amine molecules which exist in dynamic equilibrium. Using (bis)amine-silver carboxylate complex as precursor, silver nanoparticles were fabricated. During high-temperature thermolysis, the (bis)amine-carboxylate adduct decomposes to produce silver nanoparticles of small size. NPs are stabilized by strongly interacting carboxylate and trace amounts of amine derived from the silver precursor interacting with carboxylic acid. A corresponding aliphatic amide obtained from silver precursor at high-temperature reaction conditions is not taking part in the stabilization. Combining NMR techniques with FTIR, it was possible to follow an original stabilization mechanism. Graphical abstractThe synthesis of a series (bis)alkylamine silver(I) carboxylate complexes in nonpolar solvents were carried out and fully characterized both in the solid and solution. Carboxyl moieties in the presence of amine ligands are bound to silver ions via chelating bidentate type of coordination. The complexes form layered structures which thermally decompose forming nanoparticles stabilized only by aliphatic carboxylates.

Thio-,amine-,nitro-,and macrocyclic containing organic aerogels & xerogels

DOEpatents

Fox, Glenn A.; Tillotson, Thomas M.

2005-08-02

An organic aerogel or xerogel formed by a sol-gel reaction using starting materials that exhibit similar reactivity to the most commonly used resorcinol starting material. The new starting materials, including thio-, amine- and nitro-containing molecules and functionalized macrocyclic molecules will produce organic xerogels and aerogels that have improved performance in the areas of detection and sensor technology, as well as water stream remediation. Also, further functionalization of these new organic aerogels or xerogels will yield material that can be extracted with greater facility than current organic aerogels.

Memory Device and Nanofabrication Techniques Using Electrically Configurable Materials

NASA Astrophysics Data System (ADS)

Ascenso Simões, Bruno

Development of novel nanofabrication techniques and single-walled carbon nanotubes field configurable transistor (SWCNT-FCT) memory devices using electrically configurable materials is presented. A novel lithographic technique, electric lithography (EL), that uses electric field for pattern generation has been demonstrated. It can be used for patterning of biomolecules on a polymer surface and patterning of resist as well. Using electrical resist composed of a polymer having Boc protected amine group and iodonium salt, Boc group on the surface of polymer was modified to free amine by applying an electric field. On the modified surface of the polymer, Streptavidin pattern was fabricated with a sub-micron scale. Also patterning of polymer resin composed of epoxy monomers and diaryl iodonium salt by EL has been demonstrated. Reaction mechanism for electric resist configuration is believed to be induced by an acid generation via electrochemical reduction in the resist. We show a novel field configurable transistor (FCT) based on single-walled carbon nanotube network field-effect transistors in which poly (ethylene glycol) crosslinked by electron-beam is incorporated into the gate. The device conductance can be configured to arbitrary states reversibly and repeatedly by applying external gate voltages. Raman spectroscopy revealed that evolution of the ratio of D- to G-band intensity in the SWCNTs of the FCT progressively increases as the device is configured to lower conductance states. Electron transport studies at low temperatures showed a strong temperature dependence of the resistance. Band gap widening of CNTs up to ˜ 4 eV has been observed by examining the differential conductance-gate voltage-bias voltage relationship. The switching mechanism of the FCT is attributed a structural transformation of CNTs via reversible hydrogenation and dehydrogenations induced by gate voltages, which tunes the CNT bandgap continuously and reversibly to non-volatile analog values. The CNT transistors with field tunable band gaps would facilitate field programmable circuits based on the self-organized CNTs, and might also lead to novel analog memory, neuromorphic, and photonic devices.

Tandem derivatization combined with salting-out assisted liquid-liquid microextraction for determination of biothiols in urine by gas chromatography-mass spectrometry.

PubMed

Tsai, Chia-Ju; Liao, Fang-Yi; Weng, Jing-Ru; Feng, Chia-Hsien

2017-11-17

Detection of polar organic compounds (POCs) using gas chromatography (GC) is not straightforward due to high polarity, hydrophilicity, and low volatility of POCs. In this study, we report a tandem microwave-assisted derivatization method combined with salting-out assisted liquid-liquid microextraction (SALLME) to modify successively the polar groups of POCs in protic and aprotic solvents. Biothiols (cysteine and homocysteine) served as a proof of concept for this method because they possess three polar groups (thiol, amine, and carboxyl); the derivatizing reagent was 3,4,5-trifluorobenzyl bromide (Br-TFB) for alkylation. The solubility of the POCs in the protic or aprotic reaction medium affected the number of TFB molecules attached. Using the tandem derivatization with Br-TFB, the thiol and amine groups of biothiols were alkylated in the protic system, and the carboxylic groups of biothiols were alkylated in the aprotic system. The developed method was then successfully applied to measure biothiols in human urine. Because of the complex urine matrix and the lack of urine samples without endogenous biothiols, the standard addition method was utilized to avoid the matrix effect, check the recovery, and calculate the initial biothiol content in the urine. Regarding the linearity of the standard addition curves, the coefficient of determination was >0.996, and the linear regression showed satisfactory reproducibility with a relative standard deviation <3.9% for the slope and <8.8% for the intercept. The levels of cysteine and homocysteine in healthy human urine ranged from 28.8 to 111μmolL -1 and from 1.28 to 3.73μmolL -1 , respectively. The proposed method effectively increased the sensitivity of GC-MS assays of water-soluble compounds in human urine. Copyright © 2017 Elsevier B.V. All rights reserved.

Charge reversible gold nanoparticles for high efficient absorption and desorption of DNA

NASA Astrophysics Data System (ADS)

Wang, Can; Zhuang, Jiaqi; Jiang, Shan; Li, Jun; Yang, Wensheng

2012-10-01

Mercaptoundecylamine and mercaptoundecanoic acid co-modified Au nanoparticles were prepared by two-step ligand exchange of 6-mercaptohexanoic acid modified gold nanoparticles. Such particles terminated by appropriate ratios of the amine and carboxyl groups ( R N/C) were identified to show reversible charge on their surface, which were switchable by pH of the solution. The isoelectric point (IEP) of the particles is tunable by changing the ratios of the amine and carboxyl groups on the particle surfaces. The particles can absorb DNA effectively at pH lower than the IEP driven by the direct electrostatic interactions between DNA and the particle surface. When pH of the solutions was elevated to be higher than the IEP, the absorbed DNA can be released almost completely due to the electrostatic repulsion between the particle surface and DNA. With appropriate R N/C ratios of 0.8, the absorption and desorption efficiencies of DNA were 97 and 98 %, respectively, corresponding an extraction efficiency of 95 %. Such particles with reversible surface charges allow the high efficient extraction of DNA by simply changing pH instead of by changing salt concentration in the conventional salt bridge method.

Process for reducing organic compounds with calcium, amine, and alcohol

DOEpatents

Benkeser, R.A.; Laugal, J.A.; Rappa, A.

1985-08-06

Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

Effect of bentonite modification on hardness and mechanical properties of natural rubber nanocomposites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santiago, Denise Ester O.; Department of Chemical Engineering, University of the Philippines, Los Baños, College, Laguna 4031 Philippines; Pajarito, Bryan B.

The effect of sodium activation, ion-exchange with tertiary amine salt, surface treatment with non-ionic surfactant, and wet grinding of bentonite on hardness and mechanical properties of natural rubber nanocomposites (NRN) was studied using full factorial design of experiment. Results of X-ray diffraction (XRD) show increase in basal spacing d of bentonite due to modification, while attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) confirm the organic modification of bentonite. Analysis of variance (ANOVA) shows that the main effect of surface treatment increases the hardness and decreases the tensile modulus of the NRN. The surface treatment and wet grinding of bentonitemore » decrease the tensile stresses at 100, 200 and 300% strain of NRN. Sodium activation and ion-exchange negatively affect the compressive properties, while surface treatment significantly improves the compressive properties of NRN.« less

Photogeneration of singlet oxygen by the phenothiazine derivatives covalently bound to the surface-modified glassy carbon

NASA Astrophysics Data System (ADS)

Blacha-Grzechnik, Agata; Piwowar, Katarzyna; Krukiewicz, Katarzyna; Koscielniak, Piotr; Szuber, Jacek; Zak, Jerzy K.

2016-05-01

The selected group of four amine-derivatives of phenothiazine was covalently grafted to the glassy carbon surface in the four-step procedure consisting of the electrochemical reduction of the diazonium salt followed by the electrochemical and chemical post-modification steps. The proposed strategy involves the bonding of linker molecule to which the photosensitizer is attached. The synthesized organic layers were characterized by means of cyclic voltammetry, XPS and Raman Spectroscopy. It was shown that the phenothiazines immobilized via proposed strategy retain their photochemical properties and are able to generate 1O2 when activated by the laser radiation. The effectiveness of in situ singlet oxygen generation by those new solid photoactive materials was determined by means of UVVis spectroscopy. The reported, covalently modified solid surfaces may find their application as the singlet oxygen photogenerators in the fine chemicals' synthesis or in the wastewater treatment.

Development of a general non-noble metal catalyst for the benign amination of alcohols with amines and ammonia.

PubMed

Cui, Xinjiang; Dai, Xingchao; Deng, Youquan; Shi, Feng

2013-03-11

The N-alkylation of amines or ammonia with alcohols is a valuable route for the synthesis of N-alkyl amines. However, as a potentially clean and economic choice for N-alkyl amine synthesis, non-noble metal catalysts with high activity and good selectivity are rarely reported. Normally, they are severely limited due to low activity and poor generality. Herein, a simple NiCuFeOx catalyst was designed and prepared for the N-alkylation of ammonia or amines with alcohol or primary amines. N-alkyl amines with various structures were successfully synthesized in moderate to excellent yields in the absence of organic ligands and bases. Typically, primary amines could be efficiently transformed into secondary amines and N-heterocyclic compounds, and secondary amines could be N-alkylated to synthesize tertiary amines. Note that primary and secondary amines could be produced through a one-pot reaction of ammonia and alcohols. In addition to excellent catalytic performance, the catalyst itself possesses outstanding superiority, that is, it is air and moisture stable. Moreover, the magnetic property of this catalyst makes it easily separable from the reaction mixture and it could be recovered and reused for several runs without obvious deactivation. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bridging the gap between ionic liquids and molten salts: group 1 metal salts of the bistriflamide anion in the gas phase.

PubMed

Leal, João P; da Piedade, Manuel E Minas; Canongia Lopes, José N; Tomaszowska, Alina A; Esperança, José M S S; Rebelo, Luís Paulo N; Seddon, Kenneth R

2009-03-19

Fourier transform ion cyclotron resonance mass spectrometry experiments showed that liquid Group 1 metal salts of the bistriflamide anion undergoing reduced-pressure distillation exhibit a remarkable behavior that is in transition between that of the vapor-liquid equilibrium characteristics of aprotic ionic liquids and that of the Group 1 metal halides: the unperturbed vapors resemble those of aprotic ionic liquids, in the sense that they are essentially composed of discrete ion pairs. However, the formation of large aggregates through a succession of ion-molecule reactions is closer to what might be expected for Group 1 metal halides. Similar experiments were also carried out with bis{(trifluoromethyl)sulfonyl}amine to investigate the effect of H(+), which despite being the smallest Group 1 cation, is generally regarded as a nonmetal species. In this case, instead of the complex ion-molecule reaction pattern found for the vapors of Group 1 metal salts, an equilibrium similar to those observed for aprotic ionic liquids was observed.

Process for reducing organic compounds with calcium, amine, and alcohol

DOEpatents

Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

1985-01-01

Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about -10.degree. C. to about 30.degree. C. or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

A new high-speed hollow fiber based liquid phase microextraction method using volatile organic solvent for determination of aromatic amines in environmental water samples prior to high-performance liquid chromatography.

PubMed

Sarafraz-Yazdi, A; Mofazzeli, F; Es'haghi, Z

2009-07-15

A new and fast hollow fiber based liquid phase microextraction (HF-LPME) method using volatile organic solvents coupled with high-performance liquid chromatography (HPLC) was developed for determination of aromatic amines in the environmental water samples. Analytes including 3-nitroaniline, 3-chloroaniline and 4-bromoaniline were extracted from 6 mL basic aqueous sample solution (donor phase, NaOH 1 mol L(-1)) into the thin film of organic solvent that surrounded and impregnated the pores of the polypropylene hollow fiber wall (toluene, 20 microL), then back-extracted into the 6 mL acidified aqueous solution (acceptor phase, HCl 0.5 mol L(-1)) in the lumen of the two-end sealed hollow fiber. After the extraction, 5 microL of the acceptor phase was withdrawn into the syringe and injected directly into the HPLC system for the analysis. The parameters influencing the extraction efficiency including the kind of organic solvent and its volume, composition of donor and acceptor phases and the volume ratio between them, extraction time, stirring rate, salt addition and the effect of the analyte complexation with 18-crown-6 ether were investigated and optimized. Under the optimal conditions (donor phase: 6 mL of 1 mol L(-1) NaOH with 10% NaCl; organic phase: 20 microL of toluene; acceptor phase: 6 microL of 0.5 mol L(-1) HCl and 600 mmol L(-1) 18-crown-6 ether; pre-extraction and back-extraction times: 75 s and 10 min, respectively; stirring rate: 800 rpm), the obtained EFs were between 259 and 674, dynamic linear ranges were 0.1-1000 microg L(-1) (R>0.9991), and also the limits of detection were in the range of 0.01-0.1 micro gL(-1). The proposed procedure worked very well for real environmental water samples with microgram per liter level of the analytes, and good relative recoveries (91-102%) were obtained for the spiked sample solutions.

Chemistry of carbon nanomaterials: Uses of lithium nanotube salts in organic syntheses and functionalization of graphite

NASA Astrophysics Data System (ADS)

Chattopadhyay, Jayanta

The effective utilization of carbon nanomaterials, such as single-walled carbon nanotubes (SWNTs) and graphite, has been hindered due to difficulties (poor solubility, poly-dispersity) in processing. Therefore, a high degree of sidewall functionalization, either covalent or non-covalent, is often required to overcome these difficulties as the functionalized nanomaterials exhibit better solubility (either in organic solvents or in water), dispersity, manipulation, and processibility. This thesis presents a series of convenient and efficient organic synthetic routes to functionalize carbon nanomaterials. Carbon nanotube salts, prepared by treating SWNTs with lithium in liquid ammonia, react readily with aryl halides to yield aryl-functionalized SWNTs. These arylated SWNTs are soluble in methanol and water upon treatment with oleum. Similarly, SWNTs can be covalently functionalized by different heteroatoms (nitrogen, oxygen, and sulfur). Using the reductive alkylation approach, a synthetic scheme is designed to prepare long chain carboxylic acid functionalized SWNTs [SWNTs-(RCOOH)] that can react with (1) amine-terminated polyethylene glycol (PEG) chains to yield water-soluble biocompatible PEGylated SWNTs that are likely to be useful in a variety of biomedical applications; (2) polyethyleneimine (PEI) to prepare a SWNTs-PEI based adsorbent material that shows a four-fold improvement in the adsorption capacity of carbon dioxide over commonly used materials, making it useful for regenerable carbon dioxide removal in spaceflight; (3) chemically modified SWNTs-(RCOOH) to permit covalent bonding to the nylon matrix, thus allowing the formation of nylon 6,10 and nylon 6,10/SWNTs-(RCOOH) nanocomposites. Furthermore, we find that the lithium salts of carbon nanotubes serve as a source of electrons to induce polymerization of simple alkenes and alkynes onto the surface of carbon nanotubes. In the presence of sulfide/disulfide bonds, SWNT salts can initiate the single electron transfer (SET) mechanism to functionalize carbon nanotubes with different alkyl/aryl groups. Using the reductive alkylation approach, we can also functionalize graphites by alkyl/carboxylic acid groups, making graphite soluble in organic solvents and water. Tailoring of graphite layers is also accomplished by using different metals in liquid ammonia. Finally, SWNT-epoxides/graphite epoxides are synthesized using m-CPBA. Quantification of the epoxide substituents on the nanotube/graphite surface is evaluated through the catalytic de-epoxidation reaction using MeReO 3/PPh3 as heterogeneous catalyst. In summary, the proposed covalent functionalization methods yield derivatized nanomaterials that can provide a solid platform for a number of exciting applications, ranging from material science to biomedical devices. Furthermore, the results presented in this thesis provide insight into the molecular chemistry at nano-resolution.

Thermal wet decomposition of Prussian Blue: implications for prebiotic chemistry.

PubMed

Ruiz-Bermejo, Marta; Rogero, Celia; Menor-Salván, César; Osuna-Esteban, Susana; Martín-Gago, José Angel; Veintemillas-Verdaguer, Sabino

2009-09-01

The complex salt named Prussian Blue, Fe4[Fe(CN)6]3 x 15 H2O, can release cyanide at pH > 10. From the point of view of the origin of life, this fact is of interest, since the oligomers of HCN, formed in the presence of ammonium or amines, leads to a variety of biomolecules. In this work, for the first time, the thermal wet decomposition of Prussian Blue was studied. To establish the influence of temperature and reaction time on the ability of Prussian Blue to release cyanide and to subsequently generate other compounds, suspensions of Prussian Blue were heated at temperatures from room temperature to 150 degrees at pH 12 in NH3 environment for several days. The NH3 wet decomposition of Prussian Blue generated hematite, alpha-Fe2O3, the soluble complex salt (NH4)4[Fe(CN6)] x 1.5 H2O, and several organic compounds, the nature and yield of which depend on the experimental conditions. Urea, lactic acid, 5,5-dimethylhydantoin, and several amino acids and carboxylic acids were identified by their trimethylsilyl (TMS) derivatives. HCN, cyanogen (C2N2), and formamide (HCONH2) were detected in the gas phase by GC/MS analysis.

Maillard reaction of lactose and fluoxetine hydrochloride, a secondary amine.

PubMed

Wirth, D D; Baertschi, S W; Johnson, R A; Maple, S R; Miller, M S; Hallenbeck, D K; Gregg, S M

1998-01-01

Analysis of commercially available generic formulations of fluoxetine HCl revealed the presence of lactose as the most common excipient. We show that such formulations are inherently less stable than formulations with starch as the diluent due to the Maillard reaction between the drug, a secondary amine hydrochloride, and lactose. The Amadori rearrangement product was isolated and characterized; the characterization was aided by reduction with sodium borohydride and subsequent characterization of this reduced adduct. The lactose-fluoxetine HCl reaction was examined in aqueous ethanol and in the solid state, in which factors such as water content, lubricant concentration, and temperature were found to influence the degradation. N-Formylfluoxetine was identified as a major product of this Maillard reaction and it is proposed that N-formyl compounds be used as markers for this drug-excipient interaction since they are easy to prepare synthetically. Many characteristic volatile products of the Maillard reaction have been identified by GC/MS, including furaldehyde, maltol, and 2,3-dihydro-3,5-dihydroxy-6-methyl-4 H-pyran-4-one. Close similarity between the degradation products of simple mixtures and formulated generic products was found; however, at least one product decomposed at a rate nearly 10 times that predicted from the simple models. Maillard products have also been identified in unstressed capsules. The main conclusion is that drugs which are secondary amines (not just primary amines as sometimes reported) undergo the Maillard reaction with lactose under pharmaceutically relevant conditions. This finding should be considered during the selection of excipients and stability protocols for drugs which are secondary amines or their salts, just as it currently is for primary amines.

Syntheses of organic compounds in the presence of the fused iron catalyst and their mechanisms and kinetics

NASA Astrophysics Data System (ADS)

Glebov, L. S.; Kliger, G. A.

1989-10-01

New synthetic possibilities of the reduced promoted fused iron catalyst in intermolecular and intramolecular amination, cyanation, hydrogenation-dehydrogenation, and hydrodeoxygenation reactions and intermolecular and intramolecular dehydration, polymerisation, and isotope exchange are examined. The mechanisms and kinetics of the reactions leading to the synthesis of amines, alcohols, hydrocarbons, and other organic compunds are discussed. A laser Raman spectroscopic method is described for the investigation of heterogeneous organic catalysis in situ. The bibliography includes 148 references.

Studying the processes relating to oxidation of organic substances contained in the coolant of thermal and nuclear power stations

NASA Astrophysics Data System (ADS)

Khodyrev, B. N.; Krichevtsov, A. L.; Sokolyuk, A. A.

2010-07-01

A radical-chain mechanism governing thermal-oxidation destruction of organic substances contained in the coolant of thermal and nuclear power stations is considered. Hypotheses on the chemical nature of antioxidation properties of amines are presented. Theoretical conjectures about the fundamental processes through which protective amine films are formed on the surface of metals are suggested.

The roles of tertiary amine structure, background organic matter and chloramine species on NDMA formation.

PubMed

Selbes, Meric; Kim, Daekyun; Ates, Nuray; Karanfil, Tanju

2013-02-01

N-nitrosodimethylamine (NDMA), a probable human carcinogen, is a disinfection by-product that has been detected in chloraminated and chlorinated drinking waters and wastewaters. Formation mechanisms and precursors of NDMA are still not well understood. The main objectives of this study were to systematically investigate (i) the effect of tertiary amine structure, (ii) the effect of background natural organic matter (NOM), and (iii) the roles of mono vs. dichloramine species on the NDMA formation. Dimethylamine (DMA) and 20 different tertiary aliphatic and aromatic amines were carefully examined based on their functional groups attached to the basic DMA structure. The wide range (0.02-83.9%) of observed NDMA yields indicated the importance of the structure of tertiary amines, and both stability and electron distribution of the leaving group of tertiary amines on NDMA formation. DMA associated with branched alkyl groups or benzyl like structures having only one carbon between the ring and DMA structure consistently gave higher NDMA yields. Compounds with electron withdrawing groups (EWG) reacted preferentially with monochloramine, whereas compounds with electron donating group (EDG) showed tendency to react with dichloramine to form NDMA. When the selected amines were present in NOM solutions, NDMA formation increased for compounds with EWG while decreased for compounds with EDG. This impact was attributed to the competitions between NOM and amines for chloramine species. The results provided additional information to the commonly accepted mechanism for NDMA formation including chloramine species reacting with tertiary amines and the role of the leaving group on overall NDMA conversion. Copyright © 2012 Elsevier Ltd. All rights reserved.

Direct Synthesis of Protoberberine Alkaloids by Rh-Catalyzed C-H Bond Activation as the Key Step.

PubMed

Jayakumar, Jayachandran; Cheng, Chien-Hong

2016-01-26

A one-pot reaction of substituted benzaldehydes with alkyne-amines by a Rh-catalyzed C-H activation and annulation to afford various natural and unnatural protoberberine alkaloids is reported. This reaction provides a convenient route for the generation of a compound library of protoberberine salts, which recently have attracted great attention because of their diverse biological activities. In addition, pyridinium salt derivatives can also be formed in good yields from α,β-unsaturated aldehydes and amino-alkynes. This reaction proceeds with excellent regioselectivity and good functional group compatibility under mild reaction conditions by using O2 as the oxidant. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Trimethylaluminum and borane complexes of primary amines.

PubMed

Németh, Balázs; Guégan, Jean-Paul; Veszprémi, Tamás; Guillemin, Jean-Claude

2013-01-07

Trimethylaluminum (TMA) complexes of methyl-, n-propyl-, cyclopropyl-, allyl-, and propargylamine were synthesized and their experimental properties and theoretical characteristics were compared with the respective amine-borane analogues. The amine ligand of an amine-TMA Lewis acid-base complex can be easily changed by another amine through a 2:1 amine-TMA intermediate in pentane at room temperature. The exchange of the same ligands in the case of amine-boranes requires remarkably more time in line with the calculated relative energy of the respective transition state. The (1)H and (13)C NMR experiments examining the addition of one or more equivalent of amine to the respective Lewis acid-base complex conclude in the fast exchange of the amine ligand in the NMR time scale only in the cases of amine-TMA complexes, which could also be caused by similar 2:1 complexes. However, in gas phase, only 1:1 amine-TMA complexes are present as evidenced by ultraviolet photoelectron spectroscopy (UPS). The observed UP spectra, which are the first recorded photoelectron spectra of primary amine-TMA compounds, indicate that the stabilization effect of the lone electron pair of nitrogen atom in amines during the borane complexation is stronger than that of the TMA complexation. In line with this observation, the destabilization of the σ(Al-C) orbitals is lower than that of σ(B-H) orbitals during the formation of amine-TMA and amine-borane complexes, respectively. As showed by theoretical calculations, the CH(4) elimination of the studied amine-TMA complexes is exothermic, indicating the possibility of using these compounds in metal organic chemical vapor deposition techniques (MOCVD). On the other hand, our experimental conditions avoid this methane elimination and constitutes the first procedure employing distillation to isolate primary amine-TMA complexes.

A Neat Trick Using Oxalic Acid Dihydrate and Potassium Permanganate and Other Experiments with Small Organic Amine or Oxygenated Compounds

ERIC Educational Resources Information Center

Kelland, Malcolm A.

2011-01-01

Solid potassium permanganate (KMnO[subscript 4]) is shown to react in a variety of ways with small organic amines or oxygenated compounds depending on whether they are liquids or solids and whether water is present. In particular, its reaction with solid oxalic acid dihydrate can be initiated by the moisture in one's breath, making an intriguing…

Removal of Zn or Cd and cyanide from cyanide electroplating wastes

DOEpatents

Moore, Fletcher L.

1977-05-31

A method is described for the efficient stripping of stable complexes of a selected quaternary amine and a cyanide of Zn or Cd. An alkali metal hydroxide solution such as NaOH or KOH will quantitatively strip a pregnant extract of the quaternary ammonium complex of its metal and cyanide content and regenerate a quaternary ammonium hydroxide salt which can be used for extracting further metal cyanide values.

Important roles of enthalpic and entropic contributions to CO2 capture from simulated flue gas and ambient air using mesoporous silica grafted amines.

PubMed

Alkhabbaz, Mustafa A; Bollini, Praveen; Foo, Guo Shiou; Sievers, Carsten; Jones, Christopher W

2014-09-24

The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0-0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropyl-functionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less efficient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

One-step surface doping of organic nanofibers to achieve high dark conductivity and chemiresistor sensing of amines.

PubMed

Huang, Helin; Gross, Dustin E; Yang, Xiaomei; Moore, Jeffrey S; Zang, Ling

2013-08-28

High dark electrical conductivity was obtained for a p-type organic nanofibril material simply through a one-step surface doping. The nanofibril composite thus fabricated has been proven robust under ambient conditions. The high conductivity, combined with the intrinsic large surface area of the nanofibers, enables development of chemiresistor sensors for trace vapor detection of amines, with detection limit down to sub-parts per billion range.

AMINE EXTRACTION OF PLUTONIUM FROM NITRIC ACID SOLUTIONS LOADING AND STRIPPING EXPERIMENTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, A.S.

1961-01-19

Information is presented on a suitable amine processing system for plutonium nitrate. Experiments with concentrated plutonium nitrate solutions show that trilaurylamine (TLA) - xylene solvent systems did not form a second organic phase. Experiments are also reported with tri-noctylamine (TnOA)-xylene and TLA-Amsco - octyl alcohol. Two organic phases appear in both these systems at high plutonium nitrate concentrations. Data are tabulated from loading and stripping experiments. (J.R.D.)

Direct evidence of charge separation in a metal-organic framework: efficient and selective photocatalytic oxidative coupling of amines via charge and energy transfer.

PubMed

Xu, Caiyun; Liu, Hang; Li, Dandan; Su, Ji-Hu; Jiang, Hai-Long

2018-03-28

The selective aerobic oxidative coupling of amines under mild conditions is an important laboratory and commercial procedure yet a great challenge. In this work, a porphyrinic metal-organic framework, PCN-222, was employed to catalyze the reaction. Upon visible light irradiation, the semiconductor-like behavior of PCN-222 initiates charge separation, evidently generating oxygen-centered active sites in Zr-oxo clusters indicated by enhanced porphyrin π-cation radical signals. The photogenerated electrons and holes further activate oxygen and amines, respectively, to give the corresponding redox products, both of which have been detected for the first time. The porphyrin motifs generate singlet oxygen based on energy transfer to further promote the reaction. As a result, PCN-222 exhibits excellent photocatalytic activity, selectivity and recyclability, far superior to its organic counterpart, for the reaction under ambient conditions via combined energy and charge transfer.

Application of the Mars Organic Analyzer to nucleobase and amine biomarker detection.

PubMed

Skelley, Alison M; Cleaves, H James; Jayarajah, Christine N; Bada, Jeffrey L; Mathies, Richard A

2006-12-01

The Mars Organic Analyzer (MOA), a portable microfabricated capillary electrophoresis instrument being developed for planetary exploration, is used to analyze a wide variety of fluorescamine-labeled amine-containing biomarker compounds, including amino acids, mono and diaminoalkanes, amino sugars, nucleobases, and nucleobase degradation products. The nucleobases cytosine and adenine, which contain an exocyclic primary amine, were effectively labeled, separated, and detected at concentrations <500 nM. To test the general applicability of the MOA for biomarker detection, amino acids and mono- and diamines were extracted from bacterial cells using both hydrolysis and sublimation followed by analysis. The extrapolated limit of detection provided by the valine biomarker was approximately 4 x 10(3) cells per sample. Products of an NH(4)CN polymerization that simulate a prebiotic synthesis were also successfully isolated via sublimation and analyzed. Adenine and alanine/serine were detected with no additional sample cleanup at 120 +/- 13 microM and 4.1 +/- 1 microM, respectively, corresponding to a reaction yield of 0.04% and 0.0003%, respectively. This study demonstrates that the MOA provides sensitive detection and analysis of low levels of a wide variety of amine-containing organic compounds from both biological and abiotic sources.

Airborne chemical contamination of a chemically amplified resist

NASA Astrophysics Data System (ADS)

MacDonald, Scott A.; Clecak, Nicholas J.; Wendt, H. R.; Willson, C. Grant; Snyder, Clinton D.; Knors, C. J.; Deyoe, N. B.; Maltabes, John G.; Morrow, James R.; McGuire, Anne E.; Holmes, Steven J.

1991-06-01

We have found that the performance of the t-BOC/onium salt resist system is severely degraded by vapor from organic bases. This effect is very pronounced and can be observed when the coated wafers stand for 15 minutes in air containing as little as 15 parts per billion (ppb) of an organic base. The observed effect, caused by this chemical contamination, depends on the tone of the resist system. For negative tone systems the UV exposure dose, required to obtain the correct linewidth, increases. While for the positive tone system, one observes the generation of a skin at the resist-air interface. Both effects are caused by the photogenerated acid being neutralized by the airborne organic base. There are a wide variety of commonly used materials which can liberate trace amounts of volatile amines and degrade resist performance. For example, fresh paint on a laboratory wall can exhibit this detrimental effect. These effects can be minimized by storing and processing the resist coated wafers in air that has passed through a specially designed, high efficiency carbon filter. The implementation of localized air filtration, to bathe the resist in chemically pure air, enabled this resist system to operate in a manufacturing environment at a rate of 100 wafers/hour.

Fabrication of Covalently Crosslinked and Amine-Reactive Microcapsules by Reactive Layer-by-Layer Assembly of Azlactone-Containing Polymer Multilayers on Sacrificial Microparticle Templates

PubMed Central

Saurer, Eric M.; Flessner, Ryan M.; Buck, Maren E.; Lynn, David M.

2011-01-01

We report on the fabrication of covalently crosslinked and amine-reactive hollow microcapsules using ‘reactive’ layer-by-layer assembly to deposit thin polymer films on sacrificial microparticle templates. Our approach is based on the alternating deposition of layers of a synthetic polyamine and a polymer containing reactive azlactone functionality. Multilayered films composed of branched poly(ethylene imine) (BPEI) and poly(2-vinyl-4,4-dimethylazlactone) (PVDMA) were fabricated layer-by-layer on the surfaces of calcium carbonate and glass microparticle templates. After fabrication, these films contained residual azlactone functionality that was accessible for reaction with amine-containing molecules. Dissolution of the calcium carbonate or glass cores using aqueous ethylenediamine tetraacetic acid (EDTA) or hydrofluoric acid (HF), respectively, led to the formation of hollow polymer microcapsules. These microcapsules were robust enough to encapsulate and retain a model macromolecule (FITC-dextran) and were stable for at least 22 hours in high ionic strength environments, in low and high pH solutions, and in several common organic solvents. Significant differences in the behaviors of capsules fabricated on CaCO3 and glass cores were observed and characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Whereas capsules fabricated on CaCO3 templates collapsed upon drying, capsules fabricated on glass templates remained rigid and spherical. Characterization using EDS suggested that this latter behavior results, at least in part, from the presence of insoluble metal fluoride salts that are trapped or precipitate within the walls of capsules after etching of the glass cores using HF. Our results demonstrate that the assembly of BPEI/PVDMA films on sacrificial templates can be used to fabricate reactive microcapsules of potential use in a wide range of fields, including catalysis, drug and gene delivery, imaging, and biomedical research. PMID:21383867

Quantitative evaluation of inhibitory effect of various substances on anaerobic ammonia oxidation (anammox).

PubMed

Nakamura, Tomotaka; Harigaya, Yuhki; Kimura, Yuya; Kuroiwa, Megumi; Kurata, Yuhri; Isaka, Kazuichi; Suwa, Yuichi

2017-09-01

The inhibitory effect of 20 substances of various chemical species on the anaerobic ammonia oxidation (anammox) activity of an enrichment culture, predominated by Candidatus Brocadia, was determined systematically by using a 15 N tracer technique. The initial anammox rate was determined during first 25 min with a small-scale anaerobic batch incubation supplemented with possible inhibitors. Although Cu 2+ and Mn 2+ did not inhibit anammox, the remaining 18 substances [Ni 2+ , Zn 2+ , Co 2+ , [Formula: see text] , Fe 2+ , 4 amines, ethylenediaminetetraacetic acid (EDTA), ethylenediamine-N,N'-bis (2-hydroxyphenylacetic acid) (EDDHA), citric acid, nitrilotriacetic acid (NTA), N,N-dimethylacetamide (DMA), 1,4-dioxane, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF) and tetrahydrofuran (THF)] were inhibitory. Inhibitory effect of NTA, EDDHA, THF, DMF, DMA and amines on anammox was first determined in this study. Inhibitory effects of metals were re-evaluated because chelators, which may interfere inhibitory effect, have been used to dissolve metal salts into assay solution. The relative anammox activities as a function of concentration of each substance were described successfully (R 2  > 0.91) either with a linear inhibition model or with a Michaelis-Menten-based inhibition model. IC 50 values were estimated based on either model, and were compared. The IC 50 values of the 4 chelators (0.06-2.7 mM) and 5 metal ions (0.02-1.09 mM) were significantly lower than those of the 4 amines (10.6-29.1 mM) and 5 organic solvents (3.5-82 mM). Although it did not show any inhibition within 25 min, 0.1 mM Cu 2+ completely inhibited anammox activity in 240 min, suggesting that the inhibitory effect caused by Cu 2+ is time-dependent. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Biogenic amines in dry fermented sausages: a review.

PubMed

Suzzi, Giovanna; Gardini, Fausto

2003-11-15

Biogenic amines are compounds commonly present in living organisms in which they are responsible for many essential functions. They can be naturally present in many foods such as fruits and vegetables, meat, fish, chocolate and milk, but they can also be produced in high amounts by microorganisms through the activity of amino acid decarboxylases. Excessive consumption of these amines can be of health concern because their not equilibrate assumption in human organism can generate different degrees of diseases determined by their action on nervous, gastric and intestinal systems and blood pressure. High microbial counts, which characterise fermented foods, often unavoidably lead to considerable accumulation of biogenic amines, especially tyramine, 2-phenylethylamine, tryptamine, cadaverine, putrescine and histamine. However, great fluctuations of amine content are reported in the same type of product. These differences depend on many variables: the quali-quantitative composition of microbial microflora, the chemico-physical variables, the hygienic procedure adopted during production, and the availability of precursors. Dry fermented sausages are worldwide diffused fermented meat products that can be a source of biogenic amines. Even in the absence of specific rules and regulations regarding the presence of these compounds in sausages and other fermented products, an increasing attention is given to biogenic amines, especially in relation to the higher number of consumers with enhanced sensitivity to biogenic amines determined by the inhibition of the action of amino oxidases, the enzymes involved in the detoxification of these substances. The aim of this paper is to give an overview on the presence of these compounds in dry fermented sausages and to discuss the most important factors influencing their accumulation. These include process and implicit factors as well as the role of starter and nonstarter microflora growing in the different steps of sausage production. Moreover, the role of microorganisms with amino oxidase activity as starter cultures to control or reduce the accumulation of biogenic amines during ripening and storage of sausages is discussed.

AROMATIC AMINES IN AND NEAR THE BUFFALO RIVER

EPA Science Inventory

Three sediment samples taken from the Buffalo River and two soil samples taken near its bank have been analyzed for 2-propanol-extractable, basic organic compounds by using GC/MS. Eleven aromatic amines related to the commercial production of malachite green and crystal violet we...

Platinum recovery from industrial process streams by halophilic bacteria: Influence of salt species and platinum speciation.

PubMed

Maes, Synthia; Claus, Mathias; Verbeken, Kim; Wallaert, Elien; De Smet, Rebecca; Vanhaecke, Frank; Boon, Nico; Hennebel, Tom

2016-11-15

The increased use and criticality of platinum asks for the development of effective low-cost strategies for metal recovery from process and waste streams. Although biotechnological processes can be applied for the valorization of diluted aqueous industrial streams, investigations considering real stream conditions (e.g., high salt levels, acidic pH, metal speciation) are lacking. This study investigated the recovery of platinum by a halophilic microbial community in the presence of increased salt concentrations (10-80 g L -1 ), different salt matrices (phosphate salts, sea salts and NH 4 Cl) and a refinery process stream. The halophiles were able to recover 79-99% of the Pt at 10-80 g L -1 salts and at pH 2.3. Transmission electron microscopy suggested a positive correlation between intracellular Pt cluster size and elevated salt concentrations. Furthermore, the halophiles recovered 46-95% of the Pt-amine complex Pt[NH 3 ] 4 2+ from a process stream after the addition of an alternative Pt source (K 2 PtCl 4 , 0.1-1.0 g L -1 Pt). Repeated Pt-tetraamine recovery (from an industrial process stream) was obtained after concomitant addition of fresh biomass and harvesting of Pt saturated biomass. This study demonstrates how aqueous Pt streams can be transformed into Pt rich biomass, which would be an interesting feed of a precious metals refinery. Copyright © 2016 Elsevier Ltd. All rights reserved.

Functionalized boron nitride nanotubes

DOEpatents

Sainsbury, Toby; Ikuno, Takashi; Zettl, Alexander K

2014-04-22

A plasma treatment has been used to modify the surface of BNNTs. In one example, the surface of the BNNT has been modified using ammonia plasma to include amine functional groups. Amine functionalization allows BNNTs to be soluble in chloroform, which had not been possible previously. Further functionalization of amine-functionalized BNNTs with thiol-terminated organic molecules has also been demonstrated. Gold nanoparticles have been self-assembled at the surface of both amine- and thiol-functionalized boron nitride Nanotubes (BNNTs) in solution. This approach constitutes a basis for the preparation of highly functionalized BNNTs and for their utilization as nanoscale templates for assembly and integration with other nanoscale materials.

Synthesis and Structure of Hypervalent Iodine(III) Reagents Containing Phthalimidate and Application to Oxidative Amination Reactions.

PubMed

Kiyokawa, Kensuke; Kosaka, Tomoki; Kojima, Takumi; Minakata, Satoshi

2015-11-09

A new class of hypervalent iodine reagents containing phthalimidate was synthesized, and structurally characterized by X-ray analysis. The benziodoxole-based reagent displays satisfactory solubility in common organic solvents and is reasonably stable in solution as well as in the solid state. The reagent was used for the oxidative amination of the C(sp(3))-H bond of N,N-dimethylanilines. In addition, the reagent was also applicable to oxidative amination with rearrangement of trialkylamines as well as enamines that were prepared in situ from secondary amines and aldehydes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

NASA Astrophysics Data System (ADS)

Malloy, Q. G. J.; Qi, Li; Warren, B.; Cocker, D. R., III; Erupe, M. E.; Silva, P. J.

2009-03-01

Primary aliphatic amines are an important class of nitrogen containing compounds emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with O3 and NO3 have been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large aerosol mass yields (~44% for butylamine) are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<1% for all amines tested) as detected by an aerosol mass spectrometer (AMS). We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities with elevated nighttime PM loadings, when significant levels of NO3 exist.

Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

NASA Astrophysics Data System (ADS)

Malloy, Q. G. J.; Qi, Li; Warren, B.; Cocker, D. R., III; Erupe, M. E.; Silva, P. J.

2008-07-01

Primary aliphatic amines are an important class of nitrogen containing compounds found to be emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with NO3 has been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large yields of aerosol mass loadings (~44% for butylamine) are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<17% for all amines tested) as detected by an aerosol mass spectrometer (AMS). We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities and lead to elevated nighttime PM loadings, when significant levels on NO3 exist.

Toward Increasing Micropore Volume between Hybrid Layered Perovskites with Silsesquioxane Interlayers.

PubMed

Kataoka, Sho; Kamimura, Yoshihiro; Endo, Akira

2018-04-10

Hybrid organic-inorganic layered perovskites are typically nonporous solids. However, the incorporation of silsesquioxanes with a cubic cage structure as interlayer materials creates micropores between the perovskite layers. In this study, we increase in the micropore volume in layered perovskites by replacing a portion of the silsesquioxane interlayers with organic amines. In the proposed method, approximately 20% of the silsesquioxane interlayers can be replaced without changing the layer distance owing to the size of the silsesquioxane. When small amines (e.g., ethylamine) are used in this manner, the micropore volume of the obtained hybrid layered perovskites increases by as much as 44%; when large amines (e.g., phenethylamine) are used, their micropore volume decreases by as much as 43%. Through the variation of amine fraction, the micropore volume can be adjusted in the range. Finally, the magnetic moment measurements reveal that the layered perovskites with mixed interlayers exhibit ferromagnetic ordering at temperature below 20 K, thus indicating that the obtained perovskites maintain their functions as layered perovskites.

[Bacterium Arthrobacter agilis UMCV2 and diverse amines inhibit in vitro growth of wood-decay fungi].

PubMed

Orozco-Mosqueda, M Del Carmen; Valencia-Cantero, Eduardo; López-Albarrán, Pablo; Martínez-Pacheco, Mauro; Velázquez-Becerra, Crisanto

2015-01-01

The kingdom Fungi is represented by a large number of organisms, including pathogens that deteriorate the main structural components of wood, such as cellulose, hemicellulose and lignin. The aim of our work was to characterize the antifungal activity in Arthrobacter agilis UMCV2 and diverse amines against wood-decaying fungi. Four fungal organisms (designated as UMTM) were isolated from decaying wood samples obtained from a forest in Cuanajo-Michoacán, México. Two of them showed a clear enzymatic activity of cellulases, xylanases and oxido-reducing enzymes and were identified as Hypocrea (UMTM3 isolate) and Fusarium (UMTM13 isolate). In vitro, the amines showed inhibitory effect against UMTM growth and one of the amines, dimethylhexadecylamine (DMA16), exhibited strong potential as wood preventive treatment, against the attack of decaying fungi. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Ni-Catalyzed Carbon-Carbon Bond-Forming Reductive Amination.

PubMed

Heinz, Christoph; Lutz, J Patrick; Simmons, Eric M; Miller, Michael M; Ewing, William R; Doyle, Abigail G

2018-02-14

This report describes a three-component, Ni-catalyzed reductive coupling that enables the convergent synthesis of tertiary benzhydryl amines, which are challenging to access by traditional reductive amination methodologies. The reaction makes use of iminium ions generated in situ from the condensation of secondary N-trimethylsilyl amines with benzaldehydes, and these species undergo reaction with several distinct classes of organic electrophiles. The synthetic value of this process is demonstrated by a single-step synthesis of antimigraine drug flunarizine (Sibelium) and high yielding derivatization of paroxetine (Paxil) and metoprolol (Lopressor). Mechanistic investigations support a sequential oxidative addition mechanism rather than a pathway proceeding via α-amino radical formation. Accordingly, application of catalytic conditions to an intramolecular reductive coupling is demonstrated for the synthesis of endo- and exocyclic benzhydryl amines.

Purification and characterization of the amine dehydrogenase from a facultative methylotroph.

PubMed

Coleman, J P; Perry, J J

1984-01-01

Strain RA-6 is a pink-pigmented organism which can grow on a variety of substrates including methylamine. It can utilize methylamine as sole source of carbon via an isocitrate lyase negative serine pathway. Methylamine grown cells contain an inducible primary amine dehydrogenase [primary amine: (acceptor) oxidoreductase (deaminating)] which is not present in succinate grown cells. The amine dehydrogenase was purified to over 90% homogeneity. It is an acidic protein (isoelectric point of 5.37) with a molecular weight of 118,000 containing subunits with approximate molecular weights of 16,500 and 46,000. It is active on an array of primary terminal amines and is strongly inhibited by carbonyl reagents. Cytochrome c or artificial electron acceptors are required for activity; neither NAD nor NADP can serve as primary electron acceptor.

Salt permeation and exclusion in hydroxylated and functionalized silica pores.

PubMed

Leung, Kevin; Rempe, Susan B; Lorenz, Christian D

2006-03-10

We use combined ab initio molecular dynamics (AIMD), grand canonical Monte Carlo, and molecular dynamics techniques to study the effect of pore surface chemistry and confinement on the permeation of salt into silica nanopore arrays filled with water. AIMD shows that 11.6 A diameter hydroxylated silica pores are relatively stable in water, whereas amine groups on functionalized pore surfaces abstract silanol protons, turning into NH3+. Free energy calculations using an ab initio parametrized force field show that the hydroxylated pores strongly attract Na+ and repel Cl- ions. Pores lined with NH3+ have the reverse surface charge polarity. Finally, studies of ions in carbon nanotubes suggest that hydration of Cl- is more strongly frustrated by pure confinement effects than Na+.

Some variables affecting hardwood control with stem injections of 2,4,5-T.

Treesearch

John L. Arend

1967-01-01

The water-soluble amine salt was at least four times more effective than the oil-soluble ester. Concentration of the 2,4,5-T, spacing of the injections, and season of the year were also important; height of the spaced injections was not. The effects of these variables and of crown size and character of the branching on hardwood control with 2,4,5-T injections are...

Salts of the iodine oxyacids in the impregnation of adsorbent charcoal for trapping radioactive methyliodide

DOEpatents

Deitz, Victor R.; Blachly, Charles H.

1977-04-05

Radioactive iodine and radioactive methyliodide can be more than 99.7 per cent removed from the air stream of a nuclear reactor by passing the air stream through a 2-inch thick filter which is made up of impregnated charcoal prepared by contacting the charcoal with a solution containing KOH, iodine or an iodide, and an oxyacid, followed by contacting with a solution containing a tertiary amine.

Identification of amines in wintertime ambient particulate material using high resolution aerosol mass spectrometry

NASA Astrophysics Data System (ADS)

Bottenus, Courtney L. H.; Massoli, Paola; Sueper, Donna; Canagaratna, Manjula R.; VanderSchelden, Graham; Jobson, B. Thomas; VanReken, Timothy M.

2018-05-01

Significant amounts of amines were detected in fine particulate matter (PM) during ambient wintertime conditions in Yakima, WA, using a high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Positive matrix factorization (PMF) of the organic aerosol (OA) signal resulted in a six-factor solution that included two previously unreported amine OA factors. The contributions of the amine factors were strongly episodic, but the concentration of the combined amine factors was as high as 10-15 μg m-3 (2-min average) during those episodes. In one occasion, the Amine-II component was 45% of total OA signal. The Amine-I factor was dominated by spectral peaks at m/z 86 (C5H12N+) and m/z 100 (C6H14N+), while the Amine-II factor was dominated by spectral peaks at m/z 58 (C3H8N+ and C2H6N2+) and m/z 72 (C4H10N+ and C3H8N2+). The ions dominating each amine factor showed distinct time traces, suggesting different sources or formation processes. Investigation into the chemistry of the amine factors suggests a correlation with inorganic anions for Amine-I, but no evidence that the Amine-II was being neutralized by the same inorganic ions. We also excluded the presence of organonitrates (ON) in the OA. The presence of C2H4O2+ at m/z 60 (a levoglucosan fragment) in the Amine-I spectrum suggests some influence of biomass burning emissions (more specifically residential wood combustion) in this PMF factor, but wind direction suggested that the most likely sources of these amines were agricultural activities and feedlots to the S-SW of the site.

Electrochemical Capture and Release of CO2 in Aqueous Electrolytes Using an Organic Semiconductor Electrode

PubMed Central

2017-01-01

Developing efficient methods for capture and controlled release of carbon dioxide is crucial to any carbon capture and utilization technology. Herein we present an approach using an organic semiconductor electrode to electrochemically capture dissolved CO2 in aqueous electrolytes. The process relies on electrochemical reduction of a thin film of a naphthalene bisimide derivative, 2,7-bis(4-(2-(2-ethylhexyl)thiazol-4-yl)phenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone (NBIT). This molecule is specifically tailored to afford one-electron reversible and one-electron quasi-reversible reduction in aqueous conditions while not dissolving or degrading. The reduced NBIT reacts with CO2 to form a stable semicarbonate salt, which can be subsequently oxidized electrochemically to release CO2. The semicarbonate structure is confirmed by in situ IR spectroelectrochemistry. This process of capturing and releasing carbon dioxide can be realized in an oxygen-free environment under ambient pressure and temperature, with uptake efficiency for CO2 capture of ∼2.3 mmol g–1. This is on par with the best solution-phase amine chemical capture technologies available today. PMID:28378994

Control of Biogenic Amines in Food—Existing and Emerging Approaches

PubMed Central

Naila, Aishath; Flint, Steve; Fletcher, Graham; Bremer, Phil; Meerdink, Gerrit

2010-01-01

Biogenic amines have been reported in a variety of foods, such as fish, meat, cheese, vegetables, and wines. They are described as low molecular weight organic bases with aliphatic, aromatic, and heterocyclic structures. The most common biogenic amines found in foods are histamine, tyramine, cadaverine, 2-phenylethylamine, spermine, spermidine, putrescine, tryptamine, and agmatine. In addition octopamine and dopamine have been found in meat and meat products and fish. The formation of biogenic amines in food by the microbial decarboxylation of amino acids can result in consumers suffering allergic reactions, characterized by difficulty in breathing, itching, rash, vomiting, fever, and hypertension. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth through chilling and freezing. However, for many fishing based subsistence populations, such measures are not practical. Therefore, secondary control measures to prevent biogenic amine formation in foods or to reduce their levels once formed need to be considered as alternatives. Such approaches to limit microbial growth may include hydrostatic pressures, irradiation, controlled atmosphere packaging, or the use of food additives. Histamine may potentially be degraded by the use of bacterial amine oxidase or amine-negative bacteria. Only some will be cost-effective and practical for use in subsistence populations. PMID:21535566

The hydrolysis of epoxides catalyzed by inorganic ammonium salts in water: kinetic evidence for hydrogen bond catalysis.

PubMed

Nozière, B; Fache, F; Maxut, A; Fenet, B; Baudouin, A; Fine, L; Ferronato, C

2018-01-17

Naturally-occurring inorganic ammonium ions have been recently reported as efficient catalysts for some organic reactions in water, which contributes to the understanding of the chemistry in some natural environments (soils, seawater, atmospheric aerosols, …) and biological systems, and is also potentially interesting for green chemistry as many of their salts are cheap and non-toxic. In this work, the effect of NH 4 + ions on the hydrolysis of small epoxides in water was studied kinetically. The presence of NH 4 + increased the hydrolysis rate by a factor of 6 to 25 compared to pure water and these catalytic effects were shown not to result from other ions, counter-ions or from acid or base catalysis, general or specific. The small amounts of amino alcohols produced in the reactions were identified as the actual catalysts by obtaining a strong acceleration of the reactions when adding these compounds directly to the epoxides in water. Replacing the amino alcohols by other strong hydrogen-bond donors, such as trifluoroethanol (TFE) or hexafluoroisopropanol (HFIP) gave the same results, demonstrating that the kinetics of these reactions was driven by hydrogen-bond catalysis. Because of the presence of many hydrogen-bond donors in natural environments (for instance amines and hydroxy-containing compounds), hydrogen-bond catalysis is likely to contribute to many reaction rates in these environments.

Perylene Diimide Based Fluorescent Dyes for Selective Sensing of Nitroaromatic Compounds: Selective Sensing in Aqueous Medium Across Wide pH Range.

PubMed

Hariharan, P S; Pitchaimani, J; Madhu, Vedichi; Anthony, Savarimuthu Philip

2016-03-01

Water soluble perylenediimide based fluorophore salt, N,N'-bis(ethelenetrimethyl ammoniumiodide)-perylene-3,4,9,10-tetracarboxylicbisimide (PDI-1), has been used for selective fluorescence sensing of picric acid (PA) and 4-nitroaniline (4-NA) in organic as well as aqueous medium across wide pH range (1.0 to 10.0). PDI-1 showed strong fluorescence in dimethylformamide (DMF) (Φf = 0.26 (DMF) and moderate fluorescence in water. Addition of picric acid (PA) and 4-nitroaniline (4-NA) into PDI-1 in DMF/aqueous solution selectively quenches the fluorescence. The concentration dependent studies showed decrease of fluorescence linearly with increase of PA and 4-NA concentration. The interference studies demonstrate high selectivity for PA and 4-NA. Interestingly, PDI-1 showed selective fluorescence sensing of PA and 4-NA across wide pH range (1.0 to 10.0). Selective fluorescence sensing of PA and 4-NA has also been observed with trifluoroacetate (PDI-2), sulfate (PDI-3) salt of PDI-1 as well as octyl chain substituted PDI (PDI-4) without amine functionality. These studies suggest that PA and 4-NA might be having preferential interaction with PDI aromatic core and quenches the fluorescence. Thus PDI based dyes have been used for selective fluorescent sensing of explosive NACs for the first time to the best our knowledge.

Copper/amino acid catalyzed cross-couplings of aryl and vinyl halides with nucleophiles.

PubMed

Ma, Dawei; Cai, Qian

2008-11-18

Copper-assisted Ullmann-type coupling reactions are valuable transformations for organic synthesis. Researchers have extensively applied these reactions in both academic and industrial settings. However, two important issues, the high reaction temperatures (normally above 150 degrees C) and the stoichiometric amounts of copper necessary, have greatly limited the reaction scope. To solve these problems, we and other groups have recently explored the use of special ligands to promote these coupling reactions. We first showed that the structure of alpha-amino acids can accelerate Cu-assisted Ullmann reactions, leading to the coupling reactions of aryl halides and alpha-amino acids at 80-90 degrees C. In response to these encouraging results, we also discovered that an l-proline ligand facilitated the following transformations: (1) coupling of aryl halides with primary amines, cyclic secondary amines, and N-containing heterocycles at 40-90 degrees C; (2) coupling of aryl halides with sulfinic acid salts at 80-95 degrees C; (3) azidation of aryl halides and vinyl halides with sodium azide at 40-95 degrees C; (4) coupling of aryl halides with activated methylene compounds at 25-50 degrees C. In addition, we found that N,N-dimethylglycine as a ligand facilitated Cu-catalyzed biaryl ether formation at 90 degrees C. Moreover, Sonogashira reactions worked in the absence of palladium and phosphine ligands, forming enamides from vinyl halides and amides at temperatures ranging from ambient temperature up to 80 degrees C. Furthermore, we discovered that an ortho-amide group can accelerate some Ullmann-type reactions. This functional group in combination with other ligand effects allowed for aryl amination or biaryl ether formation at ambient temperature. The coupling between aryl halides and activated methylene compounds even proceeded at -45 degrees C to enantioselectively form a quaternary carbon center. Taking advantage of these results, we developed several novel approaches for the synthesis of pharmaceutically important heterocycles: 1,2-disubstituted benzimidazoles, polysubstituted indoles, N-substituted 1,3-dihydrobenzimidazol-2-ones, and substituted 3-acyl oxindoles. Our results demonstrate that an l-proline or N,N-dimethylglycine ligand can facilitate most typical Ullmann-type reactions, with reactions occurring under relatively mild conditions and using only 2-20 mol % copper catalysts. These conveniently available and inexpensive catalytic systems not only accelerate the reactions but also tolerate many more functional groups. Thus, they should find considerable application in organic synthesis.

Amphiphilic and Hydrophilic Block Copolymers from Aliphatic N-Substituted 8-Membered Cyclic Carbonates: A Versatile Macromolecular Platform for Biomedical Applications.

PubMed

Venkataraman, Shrinivas; Tan, Jeremy P K; Ng, Victor W L; Tan, Eddy W P; Hedrick, James L; Yang, Yi Yan

2017-01-09

Introduction of hydrophilic components, particularly amines and zwitterions, onto a degradable polymer platform, while maintaining precise control over the polymer composition, has been a challenge. Recognizing the importance of these hydrophilic residues in multiple aspects of the nanobiomedicine field, herein, a straightforward synthetic route to access well-defined amphiphilic and hydrophilic degradable block copolymers from diethanolamine-derived functional eight-membered N-substituted aliphatic cyclic carbonates is reported. By this route, tertiary amine, secondary amine, and zwitterion residues can be incorporated across the polymer backbone. Demonstration of pH-responsiveness of these hydrophilic residues and their utility in the development of drug-delivery vehicles, catered for the specific requirements of respective model drugs (doxorubicin and diclofenac sodium salt) are shown. As hydrophilic components in degradable polymers play crucial roles in the biological interactions, these materials offers opportunities to expand the scope and applicability of aliphatic cyclic carbonates. Our approach to these functional polycarbonates will expand the range of biocompatible and biodegradable synthetic materials available for nanobiomedicine, including drug and gene delivery, antimicrobials, and hydrophilic polymers as poly(ethylene glycol) (PEG) alternatives.

Effects of marinating on heterocyclic amine carcinogen formation in grilled chicken.

PubMed

Salmon, C P; Knize, M G; Felton, J S

1997-05-01

This study compared heterocyclic aromatic amines in marinated and unmarinated chicken breast meat flame-broiled on a propane grill. Chicken was marinated prior to grilling and the levels of several heterocyclic amines formed during cooking were determined by solid-phase extraction and HPLC. Compared with unmarinated controls, a 92-99% decrease in 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was observed in whole chicken breast marinated with a mixture of brown sugar, olive oil, cider vinegar, garlic, mustard, lemon juice and salt, then grilled for 10, 20, 30 or 40 min. Conversely, 2-amino-3, 8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) increased over 10-fold with marinating, but only at the 30 and 40 min cooking times. Marinating reduced the total detectable heterocyclic amines from 56 to 1.7 ng/g, from 158 to 10 ng/g and from 330 to 44 ng/g for grilling times of 20, 30 and 40 min, respectively. The mutagenic activity of the sample extracts was also measured, using the Ames/Salmonella assay. Mutagenic activity was lower in marinated samples cooked for 10, 20 and 30 min, but higher in the marinated samples cooked for 40 min, compared with unmarinated controls. Although a change in free amino acids, which are heterocyclic amine precursors, might explain the decrease in PhIP and increase in MeIQx, no such change was detected. Marinating chicken in one ingredient at a time showed that sugar was involved in the increased MeIQx, but the reason for the decrease in PhIP was unclear. PhIP decreased in grilled chicken after marinating with several individual ingredients. This work shows that marinating is one method that can significantly reduce PhIP concentration in grilled chicken.

Secondary battery containing zinc electrode with modified separator and method

DOEpatents

Poa, David S.; Yao, Neng-Ping

1985-01-01

A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

Secondary battery containing zinc electrode with modified separator and method

DOEpatents

Poa, D.S.

1984-02-16

A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

Enantioselective construction of C-chiral allylic sulfilimines via the iridium-catalyzed allylic amination with S,S-diphenylsulfilimine: asymmetric synthesis of primary allylic amines† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c4sc01317d Click here for additional data file.

PubMed Central

Grange, Rebecca L.; Clizbe, Elizabeth A.; Counsell, Emma J.

2015-01-01

We have devised a highly regio- and enantioselective iridium-catalyzed allylic amination reaction with the sulfur-stabilized aza-ylide, S,S-diphenylsulfilimine. This process provides a robust and scalable method for the construction of aryl-, alkyl- and alkenyl-substituted C-chiral allylic sulfilimines, which are important functional groups for organic synthesis. Additionally, the combination of the allylic amination with an in situ deprotection of the sulfilimine constitutes a convenient one-pot protocol for the construction of chiral nonracemic primary allylic amines. PMID:28936319

Strong Fluorescent Smart Organogel as a Dual Sensing Material for Volatile Acid and Organic Amine Vapors.

PubMed

Xue, Pengchong; Yao, Boqi; Wang, Panpan; Gong, Peng; Zhang, Zhenqi; Lu, Ran

2015-11-23

An L-phenylalanine derivative (C12PhBPCP) consisting of a strong emission fluorophore with benzoxazole and cyano groups is designed and synthesized to realize dual responses to volatile acid and organic amine vapors. The photophysical properties and self-assembly of the said derivative in the gel phase are also studied. C12PhBPCP can gelate organic solvents and self-assemble into 1 D nanofibers in the gels. UV/Vis absorption spectral results show H-aggregate formation during gelation, which indicates strong exciton coupling between fluorophores. Both wet gel and xerogel emit strong green fluorescence because the cyano group suppresses fluorescence quenching in the self-assemblies. Moreover, the xerogel film with strong green fluorescence can be used as a dual chemosensor for quantitative detection of volatile acid and organic amine vapors with fast response times and low detection limits owing to its large surface area and amplified fluorescence quenching. The detection limits are 796 ppt and 25 ppb for gaseous aniline and trifluoroacetic acid (TFA), respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fast reductive amination by transfer hydrogenation "on water".

PubMed

Lei, Qian; Wei, Yawen; Talwar, Dinesh; Wang, Chao; Xue, Dong; Xiao, Jianliang

2013-03-18

Reductive amination of various ketones and aldehydes by transfer hydrogenation under aqueous conditions has been developed, by using cyclometallated iridium complexes as catalysts and formate as hydrogen source. The pH value of the solution is shown to be critical for a high catalytic chemoselectivity and activity, with the best pH value being 4.8. In comparison with that in organic solvents, the reductive amination in an aqueous phase is faster, and the molar ratio of the substrate to the catalyst (S/C) can be set as high as 1×10(5) , the highest S/C value ever reported in reductive amination reactions. The catalyst is easy to access and the reaction is operationally simple, allowing a wide range of ketones and aldehydes to react with various amines in high yields. The protocol provides a practical and environmental friendly new method for the synthesis of amine compounds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

(2R)-4-Oxo-4[3-(Trifluoromethyl)-5,6-diihydro:1,2,4}triazolo[4,3-a}pyrazin-7(8H)-y1]-1-(2,4,5-trifluorophenyl)butan-2-amine: A Potent, Orally Active Dipeptidyl Peptidase IV Inhibitor for the Treatment of Type 2 Diabetes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, D.; Wang, L.; Beconi, M.

2010-11-10

A novel series of {beta}-amino amides incorporating fused heterocycles, i.e., triazolopiperazines, were synthesized and evaluated as inhibitors of dipeptidyl peptidase IV (DPP-IV) for the treatment of type 2 diabetes. (2R)-4-Oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine (1) is a potent, orally active DPP-IV inhibitor (IC{sub 50} = 18 nM) with excellent selectivity over other proline-selective peptidases, oral bioavailability in preclinical species, and in vivo efficacy in animal models. MK-0431, the phosphate salt of compound 1, was selected for development as a potential new treatment for type 2 diabetes.

Charged triblock copolymer self-assembly into charged micelles

NASA Astrophysics Data System (ADS)

Chen, Yingchao; Zhang, Ke; Zhu, Jiahua; Wooley, Karen; Pochan, Darrin; Department of Material Science; Engineering University of Delaware Team; Department of Chemistry Texas A&M University Collaboration

2011-03-01

Micelles were formed through the self-assembly of amphiphlic block copolymer poly(acrylic acid)-block-poly(methyl acrylate)-block-polystyrene (PAA-PMA-PS). ~Importantly, the polymer is complexed with diamine molecules in pure THF solution prior to water titration solvent processing-a critical aspect in the control of final micelle geometry. The addition of diamine triggers acid-base complexation ~between the carboxylic acid PAA side chains and amines. ~Remarkably uniform spheres were found to form close-packed patterns when forced into dried films and thin, solvated films when an excess of amine was used in the polymer assembly process. Surface properties and structural features of these hexagonal-packed spherical micelles with charged corona have been explored by various characterization methods including Transmission Electron Microscopy (TEM), cryogenic TEM, z-potential analysis and Dynamic Light Scattering. The forming mechanism for this pattern and morphology changes against external stimulate such as salt will be discussed.

Crystal structure of (S)-sec-butyl­ammonium l-tartrate monohydrate

PubMed Central

Publicover, Ernlie A.; Kolwich, Jennifer; Stack, Darcie L.; Doué, Alyssa J.; Ylijoki, Kai E. O.

2017-01-01

The title hydrated mol­ecular salt, C4H12N+·C4H5O6 −·H2O, was prepared by deprotonation of enanti­opure l-tartaric acid with racemic sec-butyl­amine in water. Only one enanti­omer was observed crystallographically, resulting from the combination of (S)-sec-butyl­amine with l-tartaric acid. The sec-butyl­ammonium moiety is disordered over two conformations related by rotation around the CH–CH2 bond; the refined occupancy ratio is 0.68 (1):0.32 (1). In the crystal, mol­ecules are linked through a network of O—H⋯O and N—H⋯O hydrogen-bonding inter­actions, between the ammonium H atoms, the tartrate hy­droxy H atoms, and the inter­stitial water, forming a three-dimensional supra­molecular structure. PMID:28529783

Organ specificity of the bladder carcinogen 4-aminobiphenyl in inducing DNA damage and mutation in mice.

PubMed

Yoon, Jae-In; Kim, Sang-In; Tommasi, Stella; Besaratinia, Ahmad

2012-02-01

Aromatic amines are a widespread class of environmental contaminants present in various occupational settings and tobacco smoke. Exposure to aromatic amines is a major risk factor for bladder cancer development. The etiologic involvement of aromatic amines in the genesis of bladder cancer is attributable to their ability to form DNA adducts, which upon eluding repair and causing mispairing during replication, may initiate mutagenesis. We have investigated the induction of DNA adducts in relation to mutagenesis in bladder and various nontarget organs of transgenic Big Blue mice treated weekly (i.p.) with a representative aromatic amine compound, 4-aminobiphenyl (4-ABP), for six weeks, followed by a six-week recovery period. We show an organ-specificity of 4-ABP in inducing repair-resistant DNA adducts in bladder, kidney, and liver of carcinogen-treated animals, which accords with the bioactivation pathway of this chemical in the respective organs. In confirmation, we show a predominant and sustained mutagenic effect of 4-ABP in bladder, and much weaker but significant mutagenicity of 4-ABP in the kidney and liver of carcinogen-treated mice, as reflected by the elevation of background cII mutant frequency in the respective organs. The spectrum of mutations produced in bladder of 4-ABP-treated mice matches the known mutagenic properties of 4-ABP-DNA adducts, as verified by the preponderance of induced mutations occurring at G:C base pairs (82.9%), with the vast majority being G:C→T:A transversions (47.1%). Our data support a possible etiologic role of 4-ABP in bladder carcinogenesis and provide a mechanistic view on how DNA adduct-driven mutagenesis, specifically targeted to bladder urothelium, may account for organ-specific tumorigenicity of this chemical. ©2011 AACR.

Direct peptide bioconjugation/PEGylation at tyrosine with linear and branched polymeric diazonium salts.

PubMed

Jones, Mathew W; Mantovani, Giuseppe; Blindauer, Claudia A; Ryan, Sinead M; Wang, Xuexuan; Brayden, David J; Haddleton, David M

2012-05-02

Direct polymer conjugation at peptide tyrosine residues is described. In this study Tyr residues of both leucine enkephalin and salmon calcitonin (sCT) were targeted using appropriate diazonium salt-terminated linear monomethoxy poly(ethylene glycol)s (mPEGs) and poly(mPEG) methacrylate prepared by atom transfer radical polymerization. Judicious choice of the reaction conditions-pH, stoichiometry, and chemical structure of diazonium salt-led to a high degree of site-specificity in the conjugation reaction, even in the presence of competitive peptide amino acid targets such as histidine, lysines, and N-terminal amine. In vitro studies showed that conjugation of mPEG(2000) to sCT did not affect the peptide's ability to increase intracellular cAMP induced in T47D human breast cancer cells bearing sCT receptors. Preliminary in vivo investigation showed preserved ability to reduce [Ca(2+)] plasma levels by mPEG(2000)-sCT conjugate in rat animal models. © 2012 American Chemical Society

Ion Trapping of Amines in Protozoa: A Novel Removal Mechanism for Micropollutants in Activated Sludge.

PubMed

Gulde, Rebekka; Anliker, Sabine; Kohler, Hans-Peter E; Fenner, Kathrin

2018-01-02

To optimize removal of organic micropollutants from the water cycle, understanding the processes during activated sludge treatment is essential. In this study, we hypothesize that aliphatic amines, which are highly abundant among organic micropollutants, are partly removed from the water phase in activated sludge through ion trapping in protozoa. In ion trapping, which has been extensively investigated in medical research, the neutral species of amine-containing compounds diffuse through the cell membrane and further into acidic vesicles present in eukaryotic cells such as protozoa. There they become trapped because diffusion of the positively charged species formed in the acidic vesicles is strongly hindered. We tested our hypothesis with two experiments. First, we studied the distribution of the fluorescent amine acridine orange in activated sludge by confocal fluorescence imaging. We observed intense fluorescence in distinct compartments of the protozoa, but not in the bacterial biomass. Second, we investigated the distribution of 12 amine-containing and eight control micropollutants in both regular activated sludge and sludge where the protozoa had been inactivated. In contrast to most control compounds, the amine-containing micropollutants displayed a distinctly different behavior in the noninhibited sludge compared to the inhibited one: (i) more removal from the liquid phase; (ii) deviation from first-order kinetics for the removal from the liquid phase; and (iii) higher amounts in the solid phase. These results provide strong evidence that ion trapping in protozoa occurs and that it is an important removal mechanism for amine-containing micropollutants in batch experiments with activated sludge that has so far gone unnoticed. We expect that our findings will trigger further investigations on the importance of this process in full-scale wastewater treatment systems, including its relevance for accumulation of ammonium.

ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells

DOEpatents

Bhattacharya, Raghu N [Littleton, CO

2009-11-03

The invention provides CBD ZnS/Zn(O,OH)S and spray deposited ZnS/Zn(O,OH)S buffer layers prepared from a solution of zinc salt, thiourea and ammonium hydroxide dissolved in a non-aqueous/aqueous solvent mixture or in 100% non-aqueous solvent. Non-aqueous solvents useful in the invention include methanol, isopropanol and triethyl-amine. One-step deposition procedures are described for CIS, CIGS and other solar cell devices.

Utilization of Herbicide Concentration/Exposure Time Relationships for Controlling Submersed Invasive Plants on Lake Gaston, Virginia/North Carolina

DTIC Science & Technology

2011-06-01

of efficacy in controlling invasive plant species, and are verified in aquatic and wetland field sites throughout the US. This multi-tiered...localized treatment sites, moving or still water. Chlorosis of stems and leaves with plant death in 7-10 days. 2,4-D 3 DMA liquid, BEE salt...with Eurasian watermilfoil. Formulations include a liquid dimethyl amine (DMA) and a granular clay butoxyethanol ester ( BEE ). Current Evaluations

[Deposition and burial of organic carbon in coastal salt marsh: research progress].

PubMed

Cao, Lei; Song, Jin-Ming; Li, Xue-Gang; Yuan, Hua-Mao; Li, Ning; Duan, Li-Qin

2013-07-01

Coastal salt marsh has higher potential of carbon sequestration, playing an important role in mitigating global warming, while coastal saline soil is the largest organic carbon pool in the coastal salt marsh carbon budget. To study the carbon deposition and burial in this soil is of significance for clearly understanding the carbon budget of coastal salt marsh. This paper summarized the research progress on the deposition and burial of organic carbon in coastal salt marsh from the aspects of the sources of coastal salt marsh soil organic carbon, soil organic carbon storage and deposition rate, burial mechanisms of soil organic carbon, and the relationships between the carbon sequestration in coastal salt marsh and the global climate change. Some suggestions for the future related researches were put forward: 1) to further study the underlying factors that control the variability of carbon storage in coastal salt marsh, 2) to standardize the methods for measuring the carbon storage and the deposition and burial rates of organic carbon in coastal salt marsh, 3) to quantify the lateral exchange of carbon flux between coastal salt marsh and adjacent ecosystems under the effects of tide, and 4) to approach whether the effects of global warming and the increased productivity could compensate for the increase of the organic carbon decomposition rate resulted from sediment respiration. To make clear the driving factors determining the variability of carbon sequestration rate and how the organic carbon storage is affected by climate change and anthropogenic activities would be helpful to improve the carbon sequestration capacity of coastal salt marshes in China.

Odd-Even Alternation in Tautomeric Porous Organic Cages with Exceptional Chemical Stability.

PubMed

Bera, Saibal; Basu, Arghya; Tothadi, Srinu; Garai, Bikash; Banerjee, Subhrashis; Vanka, Kumar; Banerjee, Rahul

2017-02-13

Amine-linked (C-NH) porous organic cages (POCs) are preferred over the imine-linked (C=N) POCs owing to their enhanced chemical stability. In general, amine-linked cages, obtained by the reduction of corresponding imines, are not shape-persistent in the crystalline form. Moreover, they require multistep synthesis. Herein, a one-pot synthesis of four new amine-linked organic cages by the reaction of 1,3,5-triformylphloroglucinol (Tp) with different analogues of alkanediamine is reported. The POCs resulting from the odd diamine (having an odd number of -CH 2 groups) is conformationally eclipsed, while the POCs constructed from even diamines adopt a gauche conformation. This odd-even alternation in the conformation of POCs has been supported by computational calculations. The synthetic strategy hinges on the concept of Schiff base condensation reaction followed by keto-enol tautomerization. This mechanism is the key for the exceptional chemical stability of cages and facilitates their resistance towards acids and bases. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly porous organic polymers bearing tertiary amine group and their exceptionally high CO{sub 2} uptake capacities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gomes, Ruth; Bhaumik, Asim, E-mail: msab@iacs.res.in

2015-02-15

We report a very simple and unique strategy for synthesis of a tertiary amine functionalized high surface area porous organic polymer (POP) PDVTA-1 through the co-polymerization of monomers divinylbenzene (DVB) and triallylamine (TAA) under solvothermal reaction conditions. Two different PDVTA-1 samples have been synthesized by varying the molar ratio of the monomers. The porous polymeric materials have been thoroughly characterized by solid state {sup 13}C CP MAS-NMR, FT-IR and UV–vis spectroscopy, N{sub 2} sorption, HR TEM and FE SEM to understand its chemical environment, nanostructure, bonding, morphology and related surface properties. PDVTA-1 with higher amine content (DVB/TAA=4.0) showed exceptionally highmore » CO{sub 2} uptake capacity of 85.8 wt% (19.5 mmol g{sup −1}) at 273 K and 43.69 wt% (9.93 mmol g{sup −1}) at 298 K under 3 bar pressure, whereas relatively low amine loaded material (DVB/TAA=7.0) shows uptake capacity of 59.2 wt% (13.45 mmol g{sup −1}) at 273 K and 34.36 wt% (7.81 mmol g{sup −1}) at 298 K. Highly porous nanostructure together with very high surface area and basicity at the surface due to the presence of abundant basic tertiary amine N-sites in the framework of PDVTA-1 could be responsible for very high CO{sub 2} adsorption. - Graphical abstract: Exceptionally high CO2 uptake (85.8 wt % at 273 K) has been observed over a high surface area porous organic polymer PDVTA-1 synthesized through copolymerization of divinylbenzene and triallyl amine. - Highlights: • Designing the synthesis of a new N-rich cross-linked porous organic polymer PDVTA-1. • PDVTA-1 showed mesoporosity with very high surface area of 903 m{sup 2} g{sup −1}. • High surface area and presence of basic sites facilitates the CO{sub 2} uptake. • PDVTA-1 showed exceptionally high CO{sub 2} adsorption capacity of 85.8 wt% at 273 K, 3 bar pressure.« less

Interaction of protonated merocyanine dyes with amines in organic solvents.

PubMed

Ribeiro, Eduardo Alberton; Sidooski, Thiago; Nandi, Leandro Guarezi; Machado, Vanderlei Gageiro

2011-10-15

2,6-Diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate (1a) and 4-[(1-methyl-4(1H)-pyridinylidene)-ethylidene]-2,5-cyclohexadien-1-one (2a) were protonated in organic solvents (dichloromethane, acetonitrile, and DMSO) to form 1b and 2b, respectively. The appearance of the solvatochromic bands of 1a and 2a was studied UV-vis spectrophotometrically by deprotonation of 1b and 2b in solution in the presence of the following amines: aniline (AN), N-methylaniline (NMAN), N,N-dimethylaniline (NDAN), n-butylamine (BA), diethylamine (DEA), and triethylamine (TEA). Titrations of 1b and 2b with the amines were carried out and the binding constants were determined from the titration curves in each solvent, using a mathematical model adapted from the literature which considers the simultaneous participation of two dye: amine stoichiometries, 1:1 and 1:2. The data obtained showed the following base order for the two compounds in DMSO: BA>DEA>TEA, while aromatic amines did not cause any effect. In dichloromethane, the following base order for 1b was verified: TEA>DEA>BA≫NDAN, while for 2b the order was: TEA>DEA>BA, suggesting that 1b is more acidic than 2b. The data in acetonitrile indicated for 1b and 2b the following order for the amines: DEA>TEA>BA. The diversity of the experimental data were explained based on a model that considers the level of interaction of the protonated dyes with the amines to be dependent on three aspects: (a) the basicity of the amine, which varies according to their molecular structure and the solvent in which it is dissolved, (b) the molecular structure of the dye, and (c) the solvent used to study the system. Copyright © 2011 Elsevier B.V. All rights reserved.

Identification of Organic Iodine Compounds and Their Transformation Products in Edible Iodized Salt Using Liquid Chromatography-High Resolution Mass Spectrometry.

PubMed

Yun, Lifen; Peng, Yue'e; Chang, Qing; Zhu, Qingxin; Guo, Wei; Wang, Yanxin

2017-07-05

The consumption of edible iodized salt is a key strategy to control and eliminate iodine deficiency disorders worldwide. We herein report the identification of the organic iodine compounds present in different edible iodized salt products using liquid chromatography combined with high resolution mass spectrometry. A total of 38 organic iodine compounds and their transformation products (TPs) were identified in seaweed iodine salt from China. Our experiments confirmed that the TPs were generated by the replacement of I atoms from organic iodine compounds with Cl atoms. Furthermore, the organic iodine compound contents in 4 seaweed iodine salt samples obtained from different manufacturers were measured, with significant differences in content being observed. We expect that the identification of organic iodine compounds in salt will be important for estimating the validity and safety of edible iodized salt products.

Novel amine-based presursor compounds and composite membranes thereof

DOEpatents

Lee, Eric K. L.; Tuttle, Mark E.

1989-01-01

Novel amine-based precursor compounds comprising the condensation products of dialkylenetriamine and alpha, beta-unsaturated acid halides are disclosed, as well as composite membranes containing such compounds, the membranes being useful in RO-type processes for desalination and the removal of low molecular weight organic compounds such as phenols and carboxylic acids.

A novel assay to measure tertiary and quaternary amines in wastewater: An indicator for NDMA wastewater precursors.

PubMed

Woods-Chabane, Gwen C; Glover, Caitlin M; Marti, Erica J; Dickenson, Eric R V

2017-07-01

This study examined the potential of using a novel bulk amine assay as an approximation for the tertiary and quaternary amine load in wastewaters and surface water samples, and this approximation was compared to N-nitrosodimethylamine (NDMA) formation potential using chloramines. An existing colorimetric method was examined and optimized for the detection of amines in environmental water samples. The method consists of liquid-liquid extraction followed by a catalyzed reaction to form a yet-undefined product that is known to be both a strong chromophore and fluorophore. Previous work verified that this reaction was effectively catalyzed by a number of compounds containing tertiary and quaternary amine moieties. Many tertiary and quaternary compounds are also efficient producers of NDMA under chloramination conditions, and a linear correlation was consequently derived from the bulk amine signals vs. NDMA formation potential in various wastewater samples (R 2  = 0.74; n = 24; p-value < 0.05). The results provide evidence that approximately 2% of the tertiary and quaternary amines measured can form NDMA and an estimated 0.01-1.3% of nitrogen in dissolved organic nitrogen originates from these bulk amines. The normalization of NDMA concentration by the amine measurement revealed that ozone effectively destroyed those tertiary and quaternary amine structures more likely to form NDMA in treated wastewater samples. This bulk amine assay illustrates that proxy measurements of tertiary and quaternary amines can be linked to the NDMA formation potential of a given sample, and this approach may prove useful as a characterizing tool for NDMA precursors in wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interaction of aromatic amines with iron oxides: implications for prebiotic chemistry.

PubMed

Shanker, Uma; Singh, Gurinder; Kamaluddin

2013-06-01

The interaction of aromatic amines (aniline, p-chloroaniline, p-toludine and p-anisidine) with iron oxides (goethite, akaganeite and hematite) has been studied. Maximum uptake of amines was observed around pH 7. The adsorption data obtained at neutral pH were found to follow Langmuir adsorption. Anisidine was found to be a better adsorbate probably due to its higher basicity. In alkaline medium (pH > 8), amines reacted on goethite and akaganeite to give colored products. Analysis of the products by GC-MS showed benzoquinone and azobenzene as the reaction products of aniline while p-anisidine afforded a dimer. IR analysis of the amine-iron oxide hydroxide adduct suggests that the surface acidity of iron oxide hydroxides is responsible for the interaction. The present study suggests that iron oxide hydroxides might have played a role in the stabilization of organic molecules through their surface activity and in prebiotic condensation reactions.

Stable, concentrated solutions of polyaniline using amines as gel inhibitors

DOEpatents

Wang, Hsing-Lin; Mattes, Benjamin R.

2002-01-01

Stable, concentrated solutions of high-molecular weight polyaniline using amines as gel inhibitors. Certain amine compounds (gel inhibitors) are used to form highly concentrated, stable solutions of the emeraldine base form of polyaniline in numerous organic solvents from which coatings, films and fibers are readily prepared without problems associated with rapid gelation which occurs when concentrated solutions are attempted without the use of the gel inhibitors of the present invention. Tertiary amines are used to solubilize low-molecular weight fractions (M.sub.w <120,000, M.sub.n <30,000) of the pernigraniline, emeraldine, and leucoemeraldine oxidation states of polyaniline as concentrated (>20 wt. %) polyaniline solutions, while primary and secondary amines are used to produce solutions having 15-40 wt % of high-molecular weight polyaniline [M.sub.w.gtoreq.120,000, M.sub.n.gtoreq.30,000]. Concentrated solutions of polyaniline co-polymers or ring and/or nitrogen-substituted polyanilines may also be prepared.

Doping Polymer Semiconductors by Organic Salts: Toward High-Performance Solution-Processed Organic Field-Effect Transistors.

PubMed

Hu, Yuanyuan; Rengert, Zachary D; McDowell, Caitlin; Ford, Michael J; Wang, Ming; Karki, Akchheta; Lill, Alexander T; Bazan, Guillermo C; Nguyen, Thuc-Quyen

2018-04-24

Solution-processed organic field-effect transistors (OFETs) were fabricated with the addition of an organic salt, trityl tetrakis(pentafluorophenyl)borate (TrTPFB), into thin films of donor-acceptor copolymer semiconductors. The performance of OFETs is significantly enhanced after the organic salt is incorporated. TrTPFB is confirmed to p-dope the organic semiconductors used in this study, and the doping efficiency as well as doping physics was investigated. In addition, systematic electrical and structural characterizations reveal how the doping enhances the performance of OFETs. Furthermore, it is shown that this organic salt doping method is feasible for both p- and n-doping by using different organic salts and, thus, can be utilized to achieve high-performance OFETs and organic complementary circuits.

Fluorescence Studies of Protein Crystallization Interactions

NASA Technical Reports Server (NTRS)

Pusey, Marc L.; Smith, Lori; Forsythe, Elizabeth

1999-01-01

We are investigating protein-protein interactions in under- and over-saturated crystallization solution conditions using fluorescence methods. The use of fluorescence requires fluorescent derivatives where the probe does not markedly affect the crystal packing. A number of chicken egg white lysozyme (CEWL) derivatives have been prepared, with the probes covalently attached to one of two different sites on the protein molecule; the side chain carboxyl of ASP 101, within the active site cleft, and the N-terminal amine. The ASP 101 derivatives crystallize while the N-terminal amine derivatives do not. However, the N-terminal amine is part of the contact region between adjacent 43 helix chains, and blocking this site does would not interfere with formation of these structures in solution. Preliminary FRET data have been obtained at pH 4.6, 0.1M NaAc buffer, at 5 and 7% NaCl, 4 C, using the N-terminal bound pyrene acetic acid (PAA, Ex 340 nm, Em 376 nm) and ASP 101 bound Lucifer Yellow (LY, Ex 425 nm, Em 525 nm) probe combination. The corresponding Csat values are 0.471 and 0.362 mg/ml (approximately 3.3 and approximately 2.5 x 10 (exp 5) M respectively), and all experiments were carried out at approximately Csat or lower total protein concentration. The data at both salt concentrations show a consistent trend of decreasing fluorescence yield of the donor species (PAA) with increasing total protein concentration. This decrease is apparently more pronounced at 7% NaCl, consistent with the expected increased intermolecular interactions at higher salt concentrations (reflected in the lower solubility). The estimated average distance between protein molecules at 5 x 10 (exp 6) M is approximately 70 nm, well beyond the range where any FRET can be expected. The calculated RO, where 50% of the donor energy is transferred to the acceptor, for the PAA-CEWL * LY-CEWL system is 3.28 nm, based upon a PAA-CEWL quantum efficiency of 0.41.

Method of removing and detoxifying a phosphorus-based substance

DOEpatents

Vandegrift, George F.; Steindler, Martin J.

1989-01-01

A method of removing organic phosphorus-based poisonous substances from water contaminated therewith and of subsequently destroying the toxicity of the substance is disclosed. Initially, a water-immiscible organic is immobilized on a supported liquid membrane. Thereafter, the contaminated water is contacted with one side of the supported liquid membrane to selectively dissolve the phosphorus-based substance in the organic extractant. At the same time, the other side of the supported liquid membrane is contacted with a hydroxy-affording strong base to react the phosphorus-based substance dissolved by the organic extractant with a hydroxy ion. This forms a non-toxic reaction product in the base. The organic extractant can be a water-insoluble trialkyl amine, such as trilauryl amine. The phosphorus-based substance can be phosphoryl or a thiophosphoryl.

Conductivity and transport studies of plasticized chitosan-based proton conducting biopolymer electrolytes

NASA Astrophysics Data System (ADS)

Shukur, M. F.; Yusof, Y. M.; Zawawi, S. M. M.; Illias, H. A.; Kadir, M. F. Z.

2013-11-01

This paper focuses on the conductivity and transport properties of chitosan-based solid biopolymer electrolytes containing ammonium thiocyanate (NH4SCN). The sample containing 40 wt% NH4SCN exhibited the highest conductivity value of (1.81 ± 0.50) × 10-4 S cm-1 at room temperature. Conductivity has increased to (1.51 ± 0.12) × 10-3 S cm-1 with the addition of 25 wt% glycerol. The temperature dependence of conductivity for both salted and plasticized systems obeyed the Arrhenius rule. The activation energy (Ea) was calculated for both systems and it is found that the sample with 40 wt% NH4SCN in the salted system obtained an Ea value of 0.148 eV and that for the sample containing 25 wt% glycerol in the plasticized system is 0.139 eV. From the Fourier transform infrared studies, carboxamide and amine bands shifted to lower wavenumbers, indicating that chitosan has interacted with NH4SCN salt. Changes in the C-O stretching vibration band intensity are observed at 1067 cm-1 with the addition of glycerol. The Rice and Roth model was used to explain the transport properties of the salted and plasticized systems.

Transport of the highly charged myo-inositol hexakisphosphate molecule across the red blood cell membrane: a phase transfer and biological study.

PubMed

Vincent, Stéphane P; Lehn, Jean-Marie; Lazarte, Jaime; Nicolau, Claude

2002-09-01

To address the problem of delivering highly charged small molecules, such as phytic acid (InsP(6) or IHP), across biological membranes, we investigated an approach based on a non-covalent interaction between transport molecule(s) and IHP. Thus, we synthesized a collection of compounds containing IHP ionically bound to lipophilic (but non-lipidic) ammonium or poly-ammonium cations. First, we assessed the ability of these water-soluble salts to cross a biological membrane by measuring the partition coefficients between human serum and 1-octanol. In view of the ability of IHP to act as potent effector for oxygen release, the O(2)-hemoglobin dissociation curves were then measured for the most efficient salts on whole blood. From both the biological and the physical properties of IHP-ammonium salts we determined that cycloalkylamines (or poly-amines) were the best transport molecules, especially cycloheptyl- and cyclooctylamine. Indeed, the octanol/serum partition coefficient of IHP undecacyclooctylammonium salt, is superior to 1, which is very favorable for potential uptake into the red blood cell membrane. A qualitative correlation was found between the partitioning experiments and the biological evaluations performed on whole blood.

Fabrication of biomembrane-like films on carbon electrodes using alkanethiol and diazonium salt and their application for direct electrochemistry of myoglobin.

PubMed

Anjum, Saima; Qi, Wenjing; Gao, Wenyue; Zhao, Jianming; Hanif, Saima; Aziz-Ur-Rehman; Xu, Guobao

2015-03-15

Alkanethiols generally form self-assembled monolayers on gold electrodes and the electrochemical reduction of aromatic diazonium salts is a popular method for the covalent modification of carbon. Based on the reaction of alkanethiol with aldehyde groups covalently bound on carbon surface by the electrochemical reduction of aromatic diazonium salts, a new strategy for the modification of carbon electrodes with alkanethiols has been developed. The modification of carbon surface with aldehyde groups is achieved by the electrochemical reduction of aromatic diazonium salts in situ electrogenerated from a nitro precursor, p-nitrophenylaldehyde, in the presence of nitrous acid. By this way, in situ electrogenerated p-aminophenyl aldehyde from p-nitrophenylaldehyde immediately reacts with nitrous acid, effectively minimizing the side reaction of amine groups and aldehyde groups. The as-prepared alkanethiol-modified glassy carbon electrode was further used to make biomembrane-like films by casting didodecyldimethylammonium bromide on its surface. The biomembrane-like films enable the direct electrochemistry of immobilized myoglobin for the detection of hydrogen peroxide. The response is linear over the range of 1-600μM with a detection limit of 0.3μM. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of organic wastes on water quality from processing of oil shale from the Green River Formation, Colorado, Utah, and Wyoming

USGS Publications Warehouse

Leenheer, J.A.; Noyes, T.I.

1986-01-01

A series of investigations were conducted during a 6-year research project to determine the nature and effects of organic wastes from processing of Green River Formation oil shale on water quality. Fifty percent of the organic compounds in two retort wastewaters were identified as various aromatic amines, mono- and dicarboxylic acids phenols, amides, alcohols, ketones, nitriles, and hydroxypyridines. Spent shales with carbonaceous coatings were found to have good sorbent properties for organic constituents of retort wastewaters. However, soils sampled adjacent to an in situ retort had only fair sorbent properties for organic constituents or retort wastewater, and application of retort wastewater caused disruption of soil structure characteristics and extracted soil organic matter constituents. Microbiological degradation of organic solutes in retort wastewaters was found to occur preferentially in hydrocarbons and fatty acid groups of compounds. Aromatic amines did not degrade and they inhibited bacterial growth where their concentrations were significant. Ammonia, aromatic amines, and thiocyanate persisted in groundwater contaminated by in situ oil shale retorting, but thiosulfate was quantitatively degraded one year after the burn. Thiocyanate was found to be the best conservative tracer for retort water discharged into groundwater. Natural organic solutes, isolated from groundwater in contact with Green River Formation oil shale and from the White River near Rangely, Colorado, were readily distinguished from organic constituents in retort wastewaters by molecular weight and chemical characteristic differences. (USGS)

Organic chloramines in drinking water: An assessment of formation, stability, reactivity and risk.

PubMed

How, Zuo Tong; Linge, Kathryn L; Busetti, Francesco; Joll, Cynthia A

2016-04-15

Although organic chloramines are known to form during the disinfection of drinking water with chlorine, little information is currently available on their occurrence or toxicity. In a recent in vitro study, some organic chloramines (e.g. N-chloroglycine) were found to be cytotoxic and genotoxic even at micromolar concentrations. In this paper, the formation and stability of 21 different organic chloramines, from chlorination of simple amines and amino acids, were studied, and the competition between 20 amino acids during chlorination was also investigated. For comparison, chlorination of two amides was also conducted. The formation and degradation of selected organic chloramines were measured using either direct UV spectroscopic or colorimetric detection. Although cysteine, methionine and tryptophan were the most reactive amino acids towards chlorination, they did not form organic chloramines at the chlorine to precursor molar ratios that were tested. Only 6 out of the 21 organic chloramines formed had a half-life of more than 3 h, although this group included all organic chloramines formed from amines. A health risk assessment relating stability and reactivity data from this study to toxicity and precursor abundance data from the literature indicated that only N-chloroglycine is likely to be of concern due to its stability, toxicity and abundance in water. However, given the stability of organic chloramines formed from amines, more information about the toxicity and precursor abundance for these chloramines is desirable. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reactive Uptake of Ammonia to Secondary Organic Aerosols: Kinetics of Organonitrogen Formation

NASA Astrophysics Data System (ADS)

Liu, Yongchun; Liggio, John; Staebler, Ralf; Li, Shao-Meng

2015-04-01

Organonitrogen compounds originating from the heterogeneous uptake of NH3 or amines by secondary organic aerosol (SOA) has received significant attention recently. This is primarily due to its potential contribution to brown carbon (BrC), which can absorb solar radiation and affect climate. In addition, particle phase Organonitrogen species may represent a means of altering regional nitrogen cycles and/or nitrogen deposition patterns though the sequestering of ambient ammonia which is ultimately deposited downwind. Several reduced nitrogen forming heterogeneous reactions have previously been proposed, including Schiff base and/or Mannich reactions between NH3, ammonium salts or amines and organic carbonyl functional groups in particles. In order to assess and model the possible impact of Schiff base, Mannich or other N-forming reactions (via NH3) on the radiative forcing ability of ambient SOA and/or its impact on N-deposition, the kinetics of such heterogeneous reactions are required, and yet remain largely unknown. In the current study, the uptake kinetics of NH3 to form organonitrogen compounds in SOA derived from the ozonolysis of α-pinene and the OH oxidation of m-xylene is reported for the first time from experiments performed in a 9 m3 smog chamber equipped with a High Resolution Time-of-Flight Aerosol Mass Spectrometer. The results demonstrate that particle bound organonitrogen compounds are mainly formed by NH3 uptake onto newly formed SOA (~1 hr), but relatively little onto more aged SOA. The uptake coefficients of NH3 to form organonitrogen compounds (between 0-150 min) are on the order of 10-4-10-3 and are prominently dependent upon particle acidity. Following 6 hours of reaction, the total organonitrogen mass contributed up to 10.0±1.5 wt% and 31.5±4.4 wt% to the total SOA mass from the ozonolysis of α-pinene and OH oxidation of m-xylene. The influence of VOC precursors, seed particle acidity and gaseous NH3 concentration on the obtained uptake coefficients is described. The implications of the kinetics on atmospheric BrC and N-deposition are also discussed.

Quantification of Stereochemical Communication in Metal-Organic Assemblies.

PubMed

Castilla, Ana M; Miller, Mark A; Nitschke, Jonathan R; Smulders, Maarten M J

2016-08-26

The derivation and application of a statistical mechanical model to quantify stereochemical communication in metal-organic assemblies is reported. The factors affecting the stereochemical communication within and between the metal stereocenters of the assemblies were experimentally studied by optical spectroscopy and analyzed in terms of a free energy penalty per "incorrect" amine enantiomer incorporated, and a free energy of coupling between stereocenters. These intra- and inter-vertex coupling constants are used to track the degree of stereochemical communication across a range of metal-organic assemblies (employing different ligands, peripheral amines, and metals); temperature-dependent equilibria between diastereomeric cages are also quantified. The model thus provides a unified understanding of the factors that shape the chirotopic void spaces enclosed by metal-organic container molecules.

The Mars Organic Analyzer: Instrumentation and Methods for Detecting Trace Organic Molecules in our Solar System

NASA Astrophysics Data System (ADS)

Stockton, A. M.; Kim, J.; Willis, P. A.; Lillis, R.; Amundson, R.; Beegle, L.; Butterworth, A.; Curtis, D.; Ehrenfreund, P.; Grunthaner, F.; Hazen, R.; Kaiser, R.; Ludlam, M.; Mora, M. F.; Scherer, J.; Turin, P.; Welten, K.; Williford, K.; Mathies, R. A.

2014-07-01

Mars Organic Analyzer was designed to give the Mars 2020 Mission capability to look for organic molecules, including amines, aldehydes, ketones, organic acids, thiols and polycyclic aromatic hydrocarbons, in martian samples with sub-ppb sensitivity.

"Nanorust"-catalyzed benign oxidation of amines for selective synthesis of nitriles.

PubMed

Jagadeesh, Rajenahally V; Junge, Henrik; Beller, Matthias

2015-01-01

Organic nitriles constitute key precursors and central intermediates in organic synthesis. In addition, nitriles represent a versatile motif found in numerous medicinally and biologically important compounds. Generally, these nitriles are synthesized by traditional cyanation procedures using toxic cyanides. Herein, we report the selective and environmentally benign oxidative conversion of primary amines for the synthesis of structurally diverse aromatic, aliphatic and heterocyclic nitriles using a reusable "nanorust" (nanoscale Fe2 O3 )-based catalysts applying molecular oxygen. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Saturated Heterocyclic Aminosulfonyl Fluorides: New Scaffolds for Protecting-Group-Free Synthesis of Sulfonamides.

PubMed

Zhersh, Sergey A; Blahun, Oleksandr P; Sadkova, Iryna V; Tolmachev, Andrey A; Moroz, Yurii S; Mykhailiuk, Pavel K

2018-06-12

Cyclic saturated aminosulfonyl fluorides were synthesized as their HCl salts. The compounds were found to be stable upon storage and could be used for the protecting-group-free synthesis of sulfonamides. In the presence of the -SO 2 F group, the nitrogen atom could be modified by means of acylation, arylation, or reductive amination to give products that have high potential for the synthesis of bioactive compounds. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ethylenediaminetetraacetic acid in endodontics

PubMed Central

Mohammadi, Zahed; Shalavi, Sousan; Jafarzadeh, Hamid

2013-01-01

Ethylenediaminetetraacetic acid (EDTA) is a chelating agent can bind to metals via four carboxylate and two amine groups. It is a polyamino carboxylic acid and a colorless, water-soluble solid, which is widely used to dissolve lime scale. It is produced as several salts, notably disodium EDTA and calcium disodium EDTA. EDTA reacts with the calcium ions in dentine and forms soluble calcium chelates. A review of the literature and a discussion of the different indications and considerations for its usage are presented. PMID:24966721

Molten salt oxidation of organic hazardous waste with high salt content.

PubMed

Lin, Chengqian; Chi, Yong; Jin, Yuqi; Jiang, Xuguang; Buekens, Alfons; Zhang, Qi; Chen, Jian

2018-02-01

Organic hazardous waste often contains some salt, owing to the widespread use of alkali salts during industrial manufacturing processes. These salts cause complications during the treatment of this type of waste. Molten salt oxidation is a flameless, robust thermal process, with inherent capability of destroying the organic constituents of wastes, while retaining the inorganic ingredients in the molten salt. In the present study, molten salt oxidation is employed for treating a typical organic hazardous waste with a high content of alkali salts. The hazardous waste derives from the production of thiotriazinone. Molten salt oxidation experiments have been conducted using a lab-scale molten salt oxidation reactor, and the emissions of CO, NO, SO 2 , HCl and dioxins are studied. Impacts are investigated from the composition of the molten salts, the types of feeding tube, the temperature of molten carbonates and the air factor. Results show that the waste can be oxidised effectively in a molten salt bath. Temperature of molten carbonates plays the most important role. With the temperature rising from 600 °C to 750 °C, the oxidation efficiency increases from 91.1% to 98.3%. Compared with the temperature, air factor has but a minor effect, as well as the composition of the molten salts and the type of feeding tube. The molten carbonates retain chlorine with an efficiency higher than 99.9% and the emissions of dioxins are below 8 pg TEQ g -1 sample. The present study shows that molten salt oxidation is a promising alternative for the disposal of organic hazardous wastes containing a high salt content.

Cu(OAc)2/TFA-promoted formal [3 + 3] cycloaddition/oxidation of enamines and enones for synthesis of multisubstituted aromatic amines.

PubMed

Li, Liang; Zhao, Mi-Na; Ren, Zhi-Hui; Li, Jian-Li; Guan, Zheng-Hui

2012-07-06

New strategies for the oxidative cycloaddition of enones with enamines are developed. These cycloaddition reactions directly afford substituted aromatic amines, which are important in organic chemistry, in moderate to good yield. Cu(OAc)(2)/TFA is shown to be essential to achieve high reaction efficiency.

Photocatalytic organic transformation by layered double hydroxides: highly efficient and selective oxidation of primary aromatic amines to their imines under ambient aerobic conditions.

PubMed

Yang, Xiu-Jie; Chen, Bin; Li, Xu-Bing; Zheng, Li-Qiang; Wu, Li-Zhu; Tung, Chen-Ho

2014-06-25

We report the first application of layered double hydroxide as a photocatalyst in the transformation of primary aromatic amines to their corresponding imines with high efficiency and selectivity by using oxygen in an air atmosphere as a terminal oxidant under light irradiation.

Process for separating dissolved solids from a liquid using an anti-solvent and multiple effect evaporators

DOEpatents

Daniels, Edward J.; Jody, Bassam J.; Bonsignore, Patrick V.

1994-01-01

A process and system for treating aluminum salt cake containing water soluble halide salts by contacting the salt cake with water to dissolve water soluble halide salts forming a saturated brine solution. Transporting a portion of about 25% of the saturated brine solution to a reactor and introducing into the saturated brine solution at least an equal volume of a water-miscible low-boiling organic material such as acetone to precipitate a portion of the dissolved halide salts forming a three-phase mixture of an aqueous-organic-salt solution phase and a precipitated salt phase and an organic rich phase. The precipitated salt phase is separated from the other phases and the organic rich phase is recycled to the reactor. The remainder of the saturated brine solution is sent to a multiple effect evaporator having a plurality of stages with the last stage thereof producing low grade steam which is used to boil off the organic portion of the solution which is recycled.

Process for separating dissolved solids from a liquid using an anti-solvent and multiple effect evaporators

DOEpatents

Daniels, E.J.; Jody, B.J.; Bonsignore, P.V.

1994-07-19

A process and system are disclosed for treating aluminum salt cake containing water soluble halide salts by contacting the salt cake with water to dissolve water soluble halide salts forming a saturated brine solution. Transporting a portion of about 25% of the saturated brine solution to a reactor and introducing into the saturated brine solution at least an equal volume of a water-miscible low-boiling organic material such as acetone to precipitate a portion of the dissolved halide salts forming a three-phase mixture of an aqueous-organic-salt solution phase and a precipitated salt phase and an organic rich phase. The precipitated salt phase is separated from the other phases and the organic rich phase is recycled to the reactor. The remainder of the saturated brine solution is sent to a multiple effect evaporator having a plurality of stages with the last stage thereof producing low grade steam which is used to boil off the organic portion of the solution which is recycled. 3 figs.

On Organic Material in E Ring Ice Grains

NASA Astrophysics Data System (ADS)

Postberg, F.; Khawaja, N.; Reviol, R.; Nölle, L.; Klenner, F.; Hsu, H. W.; Horanyi, M.

2015-12-01

Pure water ice dominates the composition of the micron and sub-micron sized dust particles in Saturn's E-ring, a ring constantly replenished by active ice jets of the moon Enceladus [1]. Details about the composition of this tenuous, optically thin ring can only be constrained by in situ measurements. The Cosmic Dust Analyzer (CDA) onboard Cassini investigates the composition of these grains by cationic time-of-flight mass spectra of individual ice grains hitting the instruments target surface. From these spectra three compositional types of E ring ice grains have been identified previously [2,3]: Type-1: Almost pure water, Type-2: Enriched in organics, and Type-3: Enriched in salt. Unlike Type-1 and 3, organic-enriched Type-2 spectra have not yet been investigated in depth. Here we report the first detailed compositional analysis of this type. The spectra analysis is supported by a large-scale laboratory ground campaign yielding a library of analogue spectra for organic material embedded in a water ice matrix. In contrast to Type 1 and 3, Type-2 spectra display a great compositional diversity, which indicates varying contributions of several organic species. So far we have identified characteristic fragment patterns of at least three classes of organic compounds: aromatic species, amines, and carbonyl group species. Work is in progress to quantify concentrations of the identified species and to assign yet un-specified organic mass lines in Type 2 spectra. Due to the dynamical evolution of the orbital elements of E ring grains a large fraction collides with the icy moons embedded in the E ring. Therefore, the organic components identified by CDA can accumulate on the surfaces of these bodies over time. Ref: :[1]Kempf et al., Icarus-206, 2010. [2]Postberg et al., Nature-459, 2009. [3]Postberg et al., Icarus-193, 2008.

Identification of Organics in Ice Grains from Enceladus

NASA Astrophysics Data System (ADS)

Khawaja, N.; Postberg, F.; Reviol, R.; Nölle, L.; Klenner, F.; Srama, R.

2015-12-01

The Cosmic Dust Analyzer (CDA) aboard the Cassini spacecraft performs in-situ measurements of the chemical composition of icy dust grains impinging onto the target surface. The instrument recorded cationic Time-of-Flight (ToF) mass spectra of organic-bearing ice grains emitted from Enceladus at different impact velocities causing different molecular fragmentation patterns [1,2]. Here we present a detailed analysis of these spectra (Type-2) to identify the composition of organic material embedded in Enceladus ice grains. The organic compounds display a great compositional diversity, which indicates varying contributions of several organic species. The spectra analysis is supported by a large-scale laboratory ground campaign yielding a library of analogue spectra for organic material embedded in a water ice matrix. To mimic the identified pattern of cationic fragments in organic enriched spectra we use a laboratory setup: Infrared Free Liquid MALDI ToF Mass Spectrometer (IR-FL-MALDI-ToF-MS). An infrared laser is used to disperse a liquid micro-beam of a water-solution to get cationic fragments. The laser energy is adjusted to simulate different impact velocities of ice particles on CDA [3]. So far we have identified characteristic fragment patterns of at least three classes of organic molecules: (i) aromatic species, (ii) amines, and (iii) carbonyl group species. (i) ice grains containing aromatic species are identified by a series of characteristic aromatic fragment cations (ii) ice grains containing amines are identified by a pronounced ammonium cation and (iii) ice grains containing carbonyl compounds are specified by a characteristic acylium cation in conjunction with certain others mass lines. Besides aromatic, amine and carbonyl species, Type-2 spectra also show contributions from other, yet un-specified, organic species. Typically, fragment cations of aromatic compounds are stable at impact velocities up-to 15km/s whereas cations of amines and carbonyl species are stable at velocities below 8km/s. Work is in progress to quantify concentrations of the identified species and to assign yet un-specified organic mass lines in Type 2 spectra. Ref: [1]Postberg et al., Icarus-193,2008. [2]Postberg et al., Nature-459,2009. [3]Beinsen, A., University of Göttingen, Dissertation (2011).

Spectroscopic Evidence for Covalent Binding of Sulfadiazine to Natural Soils via 1,4-nucleophilic addition (Michael Type Addition) studied by Spin Labeling ESR

NASA Astrophysics Data System (ADS)

Aleksandrova, Olga

2015-04-01

Among different classes of veterinary pharmaceuticals, Sulfadiazine (SDZ) is widely used in animal husbandry. Its residues were detected in different environmental compartments. However, soil is a hot spot for SDZ as it receives a large portion of excreted compounds through the application of manure during soil fertilization. Ample studies on the fate of SDZ in soils showed that a large portion forms nonextractable residues (NER) along with transformation products and a low mineralization (Mueller et al., 2013). A common observation was an initially fast formation of NER up to 10% of the applied amount promptly after the application of SDZ to soil, and this portion increased up to 50% within a few days (Mueller et al., 2013; Nowak et al., 2011). A common finding for SDZ, as for other sulfonamides, was biphasic kinetics of the formation of NER, which was attributed to the occurrence of two reaction processes: a rapid, often reversible process and a slower, irreversible process (Weber et al., 1996). A single-phase reaction process was also established under anaerobic treatment (Gulkowska et al., 2014). A major focus of this work is to elucidate a reaction mechanism of covalent binding of SDZ to soil that is currently required to estimate a risk of NER formed by SDZ in soils for human health. Taking into account a key role of the amine functional groups of SDZ on its reactivity in soil, nitroxide radicals with the sewed aromatic or aliphatic amines labeled soil samples and then, were investigated by means of ESR spectroscopy. 2,5,5-Trimethyl-2-(3-aminophenyl)pyrrolidin-1-yloxy and 4-amino-2,2,6,6-Tetramethylpiperidin-1-oxyl modeled decomposition products of SDZ with the aromatic and aliphatic amines, respectively. The application of the defined combination of both spin labels (SL) to different soils well simulated a change of a paramagnetic signal of soil organic radicals interacted with SDZ. After their application to soil, SL were found in soil sites characterized with different polarity. As shown by the spin labeling ESR experiment, molecules modeling SDZ were promptly bound to non-hydrolysable network of soil organic matter only via the aromatic amines that was accompanied by a prompt enlargement of humic particles binding aromatic amines, whereas binding of decomposition products of SDZ to humic acids of soil via the aliphatic amines was not observable. The ESR spectra obviously showed a single-phase process of covalent binding of the aromatic amines. Repeated washouts of labeled soil samples using distil water and ultrafiltration through the membrane of 5000 MWCO PES confirmed irreversible binding of the aromatic amines, and showed that via the aliphatic amines, binding of SDZ or decomposition products of SDZ to soil might also occur but reversibly and only to small soil molecules, which don't enter into the composition of non-hydrolysable part of soil organic matter. SL ESR experiments of different soils at the presence of Laccase highlighted that covalent binding of the aromatic amines to humic particles occurred in the specific hydrophobic areas of soil found as depleted in oxygen. All measured data evidenced that first, SDZ might be decomposed that allowed for measuring the same change of a paramagnetic signal of soil organic matter influenced by both aromatic and aliphatic amines as in the experiment of the interaction of soil with SDZ. Second, a decomposition product of SDZ with the aromatic amine might be bound to non-hydrolysable parts of soil organic matter under specific anaerobic conditions only via 1,4 - nucleophilic addition, Michael-type addition. Gulkowska, A., Thalmann, B., D., Hollender, J., & Krauss, M. (2014). Chemosphere, 107, 366 - 372. Müller, T., Rosendahl, I., Focks, A., Siemens, J., Klasmeier, J., & Matthies. (2013). Environmental Pollution, 172,180 - 185. Nowak, K.M., Miltner, A., Gehre, M., Schaeffer, A., & Kaestner, M. (2011). Environmental Science & Technology 45, 999 - 1006. Weber, E.J., Spidle, D.L., & Thron, K.A. (1996). Environmental Science & Technology, 30 (9), 2755-2763.

Energy storage devices having anodes containing Mg and electrolytes utilized therein

DOEpatents

Shao, Yuyan; Liu, Jun

2015-08-18

For a metal anode in a battery, the capacity fade is a significant consideration. In energy storage devices having an anode that includes Mg, the cycling stability can be improved by an electrolyte having a first salt, a second salt, and an organic solvent. Examples of the organic solvent include diglyme, triglyme, tetraglyme, or a combination thereof. The first salt can have a magnesium cation and be substantially soluble in the organic solvent. The second salt can enhance the solubility of the first salt and can have a magnesium cation or a lithium cation. The first salt, the second salt, or both have a BH.sub.4 anion.

Comprehensive analysis of "bath salts" purchased from California stores and the internet.

PubMed

Schneir, A; Ly, B T; Casagrande, K; Darracq, M; Offerman, S R; Thornton, S; Smollin, C; Vohra, R; Rangun, C; Tomaszewski, C; Gerona, R R

2014-08-01

To analyze the contents of "bath salt" products purchased from California stores and the Internet qualitatively and quantitatively in a comprehensive manner. A convenience sample of "bath salt" products were purchased in person by multiple authors at retail stores in six California cities and over the Internet (U.S. sites only), between August 11, 2011 and December 15, 2011. Liquid chromatography-time-of-flight mass spectrometry was utilized to identify and quantify all substances in the purchased products. Thirty-five "bath salt" products were purchased and analyzed. Prices ranged from $9.95 to 49.99 (U.S. dollars). Most products had a warning against use. The majority (32/35, 91%) had one (n = 15) or multiple cathinones (n = 17) present. Fourteen different cathinones were identified, 3,4-methylenedioxypyrovalerone (MDPV) being the most common. Multiple drugs found including cathinones (buphedrone, ethcathinone, ethylone, MDPBP, and PBP), other designer amines (ethylamphetamine, fluoramphetamine, and 5-IAI), and the antihistamine doxylamine had not been previously identified in U.S. "bath salt" products. Quantification revealed high stimulant content and in some cases dramatic differences in either total cathinone or synthetic stimulant content between products with the same declared weight and even between identically named and outwardly appearing products. Comprehensive analysis of "bath salts" purchased from California stores and the Internet revealed the products to consistently contain cathinones, alone, or in different combinations, sometimes in high quantity. Multiple cathinones and other drugs found had not been previously identified in U.S. "bath salt" products. High total stimulant content in some products and variable qualitative and quantitative composition amongst products were demonstrated.

Catanionic mixtures forming gemini-like amphiphiles.

PubMed

Sakai, Hideki; Okabe, Yuji; Tsuchiya, Koji; Sakai, Kenichi; Abe, Masahiko

2011-01-01

The properties of aqueous mixtures of cationic species with alkyl dicarboxylic acid compounds have been studied. The cationic compounds used in this study were tertiary amine-type N-methyl-N-(2,3-dioxypropyl)hexadecylamine (C16amine) and quaternary ammonium-type N,N-dimethyl-N-(2,3-dioxypropyl)hexadecylammonium chloride (C16Q). The alkyl dicarboxylic acid compounds used were HOOC(CH(2))(10)COOH (C12H) and its sodium salt (C12Na). Three aqueous mixtures were examined in this study: (System I) C16amine + C12H, (System II) C16Q + C12Na, and (System III) C16Q + C12H. The solution pH was set at 12 for System III. The combination of (1)H-NMR and mass spectroscopy data has suggested that a stoichiometric complex is formed in the aqueous solutions at a mole fraction of C12H (or C12Na) = 0.33. Here, the C12H (or C12Na) molecule added to the system bridges two cationic molecules, like a spacer of gemini surfactants. In fact, the static surface tensiometry has demonstrated that the stoichiometric complex behaves as gemini-like amphiphiles in aqueous solutions. Our current study offers a possible way for easily preparing gemini surfactant systems.

Transition Metal-Free Selective Double sp(3) C-H Oxidation of Cyclic Amines to 3-Alkoxyamine Lactams.

PubMed

Osorio-Nieto, Urbano; Chamorro-Arenas, Delfino; Quintero, Leticia; Höpfl, Herbert; Sartillo-Piscil, Fernando

2016-09-16

The first chemical method for selective dual sp(3) C-H functionalization at the alpha-and beta positions of cyclic amines to their corresponding 3-alkoxyamine lactams is reported. Unlike traditional Cα-H oxidation of amines to amides mediated by transition metals, the present protocol, which involves the use of NaClO2/TEMPO/NaClO in either aqueous or organic solvent, not only allows the Cα-H oxidation but also the subsequent functionalization of the unreactive β-methylene group in an unprecedented tandem fashion and using environmentally friendly reactants.

Effective removal of effluent organic matter (EfOM) from bio-treated coking wastewater by a recyclable aminated hyper-cross-linked polymer.

PubMed

Yang, Wenlan; Li, Xuchun; Pan, Bingcai; Lv, Lu; Zhang, Weiming

2013-09-01

Effluent organic matter (EfOM) is a complex matrix of organic substance mainly from bio-treated sewage effluent and is considered as the main constraint to further advanced treatment. Here a recyclable aminated hyper-cross-linked polymeric adsorbent (NDA-802) featured with aminated functional groups, large specific surface area, and sufficient micropore region was synthesized for effective removal of EfOM from the bio-treated coking wastewater (BTCW), and its removal characteristics was investigated. It was found that hydrophobic fraction was the main constituent (64.8% of DOC) in EfOM of BTCW, and the hydrophobic-neutral fraction had the highest SUVA level (7.06 L mg(-1) m(-1)), which were significantly different from that in the domestic wastewater. Column adsorption experiments showed that NDA-802 exhibited much higher removal efficiency of EfOM than other polymeric adsorbents D-301, XAD-4, and XAD-7, and the efficiency could be readily sustained according to continuous 28-cycle batch adsorption-regeneration experiments. Moreover, dissolved organic matter (DOM) fractionation and excitation-emission matrix (EEM) fluorescence spectroscopy study indicated that NDA-802 showed attractive adsorption preference as well as high removal efficiency of hydrophobic and aromatic compounds. Possibly ascribed to the presence of functional aminated groups, relatively large specific surface area and micropore region of the unique polymer, NDA-802 possesses high and sustained efficiency for the removal of EfOM, and provides a potential alternative for the advanced treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Amine content of vaginal fluid from untreated and treated patients with nonspecific vaginitis.

PubMed Central

Chen, K C; Forsyth, P S; Buchanan, T M; Holmes, K K

1979-01-01

We examined the vaginal washings from patients with nonspecific vaginitis (NSV) to seek biochemical markers and possible explanations for the signs and symptoms of this syndrome. Seven amines were identified including methylamine, isobutylamine, putrescine, cadaverine, histamine, tyramine, and phenethylamine. These amines may contribute to the symptoms of NSV and may contribute to the elevated pH of the vaginal discharge. They may also be partly responsible for the "fishy" odor that is characteristic of vaginal discharges from these patients. Among the seven amines, putrescine and cadaverine were the most abundant and were present in all vaginal discharges from each of ten patients before treatment. These amines are produced in vitro during growth of mixed vaginal bacteria in chemically defined medium, presumably by decarboxylation of the corresponding amino acids. We hypothesize the anaerobic vaginal organisms, previously shown to be quantitatively increased in NSV, are responsible for the amine production, because metronidazole inhibited the production of amines by vaginal bacteria in vitro, and Haemophilus vaginalis did not produce amines. H. vaginalis did release high concentrations of pyruvic acid and of amino acids during growth in peptone-starch-dextrose medium, whereas, other vaginal flora consumed both pyruvic acid and amino acids in the same medium during growth. These findings suggest that a symbiotic relationship may exist between H. vaginalis and other vaginal flora in patients with NSV. Images PMID:447831

Ion conducting organic/inorganic hybrid polymers

NASA Technical Reports Server (NTRS)

Meador, Maryann B. (Inventor); Kinder, James D. (Inventor)

2010-01-01

This invention relates to a series of organic/inorganic hybrid polymers that are easy to fabricate into dimensionally stable films with good ion-conductivity over a wide range of temperatures for use in a variety of applications. The polymers are prepared by the reaction of amines, preferably diamines and mixtures thereof with monoamines with epoxy-functionalized alkoxysilanes. The products of the reaction are polymerized by hydrolysis of the alkoxysilane groups to produce an organic-containing silica network. Suitable functionality introduced into the amine and alkoxysilane groups produce solid polymeric membranes which conduct ions for use in fuel cells, high-performance solid state batteries, chemical sensors, electrochemical capacitors, electro-chromic windows or displays, analog memory devices and the like.

Clustering of amines and hydrazines in atmospheric nucleation

NASA Astrophysics Data System (ADS)

Li, Siyang; Qu, Kun; Zhao, Hailiang; Ding, Lei; Du, Lin

2016-06-01

It has been proved that the presence of amines in the atmosphere can enhance aerosol formation. Hydrazine (HD) and its substituted derivatives, monomethylhydrazine (MMH) and unsymmetrical dimethylhydrazine (UDMH), which are organic derivatives of amine and ammonia, are common trace atmospheric species that may contribute to the growth of nucleation clusters. The structures of the hydrazine and amine clusters containing one or two common nucleation molecules (ammonia, water, methanol and sulfuric acid) have been optimized using density functional theory (DFT) methods. The clusters growth mechanism has been explored from the thermochemistry by calculating the Gibbs free energies of adding an ammonia, water, methanol or sulfuric acid molecule step by step at room temperature, respectively. The results show that hydrazine and its derivatives could enhance heteromolecular homogeneous nucleation in the earth's atmosphere.

Hygroscopicity of dicarbonyl-amine secondary organic aerosol products investigated with HTDMA

NASA Astrophysics Data System (ADS)

Hawkins, L. N.; de Haan, D. O.

2010-12-01

Recent studies have shown the importance of amine-dicarbonyl chemistry as a secondary organic aerosol (SOA) formation pathway, producing imines, imidazoles, and N-containing oligomers. Preliminary work in our group has suggested that some of these products may be surface active. Therefore, the presence of these products may result in important changes to submicron particle hygroscopicity that affect aerosol scattering and cloud condensation nuclei (CCN) activity, especially in regions with significant amine-containing particles. To investigate their hygroscopicity, we have designed a hygroscopicity tandem differential mobility analyzer (HTDMA) system around a 300 L Teflon chamber that allows for longer humidification times needed for some organic aerosol components that are only slightly hygroscopic. This modification provides a range of residence times from 2.5 minutes up to 1 hour, unlike previously published systems that vary from 2-30 seconds. Using the modified hygroscopicity tandem differential mobility analyzer (HTDMA), we have measured the hygroscopic growth factor (HGF) of SOA formed from reactions of glyoxal (and methylglyoxal) with methylamine, ammonium sulfate, and several amino acids. Changes to inorganic aerosol HGF in response to the presence of SOA products are also investigated.

Tethered tertiary amines as solid-state n-type dopants for solution-processable organic semiconductors

DOE PAGES

Russ, Boris; Robb, Maxwell J.; Popere, Bhooshan C.; ...

2015-12-09

A scarcity of stable n-type doping strategies compatible with facile processing has been a major impediment to the advancement of organic electronic devices. Localizing dopants near the cores of conductive molecules can lead to improved efficacy of doping. We and others recently showed the effectiveness of tethering dopants covalently to an electron-deficient aromatic molecule using trimethylammonium functionalization with hydroxide counterions linked to a perylene diimide core by alkyl spacers. In this work, we demonstrate that, contrary to previous hypotheses, the main driver responsible for the highly effective doping observed in thin films is the formation of tethered tertiary amine moietiesmore » during thin film processing. Furthermore, we demonstrate that tethered tertiary amine groups are powerful and general n-doping motifs for the successful generation of free electron carriers in the solid-state, not only when coupled to the perylene diimide molecular core, but also when linked with other small molecule systems including naphthalene diimide, diketopyrrolopyrrole, and fullerene derivatives. Our findings help expand a promising molecular design strategy for future enhancements of n-type organic electronic materials.« less

Tethered tertiary amines as solid-state n-type dopants for solution-processable organic semiconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russ, Boris; Robb, Maxwell J.; Popere, Bhooshan C.

A scarcity of stable n-type doping strategies compatible with facile processing has been a major impediment to the advancement of organic electronic devices. Localizing dopants near the cores of conductive molecules can lead to improved efficacy of doping. We and others recently showed the effectiveness of tethering dopants covalently to an electron-deficient aromatic molecule using trimethylammonium functionalization with hydroxide counterions linked to a perylene diimide core by alkyl spacers. In this work, we demonstrate that, contrary to previous hypotheses, the main driver responsible for the highly effective doping observed in thin films is the formation of tethered tertiary amine moietiesmore » during thin film processing. Furthermore, we demonstrate that tethered tertiary amine groups are powerful and general n-doping motifs for the successful generation of free electron carriers in the solid-state, not only when coupled to the perylene diimide molecular core, but also when linked with other small molecule systems including naphthalene diimide, diketopyrrolopyrrole, and fullerene derivatives. Our findings help expand a promising molecular design strategy for future enhancements of n-type organic electronic materials.« less

Effects of cationic species on visual color formation in model Maillard reactions of pentose sugars and amino acids.

PubMed

Rizzi, George P

2008-08-27

Effects of cationic species on Maillard browning were examined after heating (ca. 100 degrees C) aqueous pH 7.2 buffered solutions of amino acids and pentose sugars. Metallic ions of Group I metals (Li, Na, K, Rb and Cs) produced a small increase in browning (A420), but somewhat greater effects were observed with ions of Group II metals Ca and Mg. Browning was suppressed by triethylammonium ion, but unaffected by a salt of the stronger base, guanidine. The quaternary amine salt choline chloride produced enhanced browning and served as a model for phospholipid involvement in Maillard reactions. With alpha,omega-diamino acids increases in browning were observed which related to lowered pK2 values resulting from positively charged omega-substituents in these molecules.

Evaluation of autochthonous micrococcus strains as starter cultures for the production of Kedong sufu.

PubMed

Feng, Z; Huang, S; Ai, Z W; Zhang, M; Zhai, S; Chen, X

2016-03-01

The technological properties of 22 micrococcus strains from traditional fermented Kedong sufu were evaluated in order to develop autochthonous starter cultures. The proteolytic, autolytic and lipolytic activity, salt tolerance, production and degradation of the biogenic amines of six Micrococcus luteus, nine Kocuria kristinae and seven Kocuria rosea were evaluated. The results indicated that these micrococcus strains exhibited a certain technological diversity, and the results also indicated the best properties to be used in mixed starter cultures. Based on the above findings, two sets of autochthonous starters were formulated. Considering the physicochemical properties and sensory characteristics of sufu, the maturation period of sufu was shortened by 30 days. The profiles of free amino acids and peptides partly revealed the mechanism of sensory quality and shorter ripening time of sufu manufactured using autochthonous mixed starters. Compared to back-slopping fermentation, sufu manufactured with selected autochthonous starter cultures exhibited lower levels of total biogenic amines. The selected strains could be used as starter to avoid the accumulation of high concentrations of biogenic amines while also maintaining typical sensory characteristics and preserving the autochthonous strains of the traditional Kedong sufu. The maturation times of Kedong sufu were shortened by 30 days with application of the autochthonous starter. Autochthonous mixed starters can reduce the generation of biogenic amines, speed up the sufu maturation process and preserve typical sensory quality. Furthermore, the rotation of two sets of mixed starter cultures can effectively resist phage attack during the production of sufu. © 2015 The Society for Applied Microbiology.

Process for producing organic products containing silicon, hydrogen, nitrogen, and carbon by the direct reaction between elemental silicon and organic amines and products formed thereby

DOEpatents

Pugar, E.A.; Morgan, P.E.D.

1988-04-04

A process is disclosed for producing, at a low temperature, a high purity organic reaction product consisting essentially of silicon, hydrogen, nitrogen, and carbon. The process comprises reacting together a particulate elemental high purity silicon with a high purity reactive amine reactant in a liquid state at a temperature of from about O/degree/C up to about 300/degree/C. A high purity silicon carbide/silicon nitride ceramic product can be formed from this intermediate product, if desired, by heating the intermediate product at a temperature of from about 1200-1700/degree/C for a period from about 15 minutes up to about 2 hours or the organic reaction product may be employed in other chemical uses.

Process for producing organic products containing silicon, hydrogen, nitrogen, and carbon by the direct reaction between elemental silicon and organic amines

DOEpatents

Pugar, Eloise A.; Morgan, Peter E. D.

1990-04-03

A process is disclosed for producing, at a low temperature, a high purity organic reaction product consisting essentially of silicon, hydrogen, nitrogen, and carbon. The process comprises reacting together a particulate elemental high purity silicon with a high purity reactive amine reactant in a liquid state at a temperature of from about 0.degree. C. up to about 300.degree. C. A high purity silicon carbide/silicon nitride ceramic product can be formed from this intermediate product, if desired, by heating the intermediate product at a temperature of from about 1200.degree.-1700.degree. C. for a period from about 15 minutes up to about 2 hours or the organic reaction product may be employed in other chemical uses.

Rhenium complexes of bidentate, bis-bidentate and tridentate N-heterocyclic carbene ligands.

PubMed

Chan, Chung Ying; Barnard, Peter J

2015-11-28

A series of eight Rhenium(I)-N-heterocyclic carbene (NHC) complexes of the general form [ReCl(CO)3(C^C)] (where C^C is a bis(NHC) bidentate ligand), [ReCl(CO)3(C^C)]2 (where C^C is a bis-bidentate tetra-NHC ligand) and [Re(CO)3(C^N^C)](+)[X](-) (where C^N^C is a bis(NHC)-amine ligand and the counter ion X is either the ReO4(-) or PF6(-)) have been synthesised using a Ag2O transmetallation protocol. The novel precursor imidazolium salts and Re(I) complexes were characterized by elemental analysis, (1)H and (13)C NMR spectroscopy and the molecular structures for two imidazolium salt and six Re(I) complexes were determined by single crystal X-ray diffraction. These NHC ligand systems are of interest for possible applications in the development of Tc-99m or Re-186/188 radiopharmaceuticals and as such the stability of two complexes of the form [ReCl(CO)3(C^C)] and [Re(CO)3(C^N^C)][ReO4] were evaluated in ligand challenge experiments using the metal binding amino acids L-histidine or L-cysteine. These studies showed that the former was unstable, with the chloride ligand being replaced by either cysteine or histidine, while no evidence for transchelation was observed for the latter suggesting that bis(NHC)-amine ligands of this type may be suitable for biological applications.

Histamine intolerance and dietary management: A complete review.

PubMed

San Mauro Martin, I; Brachero, S; Garicano Vilar, E

2016-01-01

Present in several types of food, bioactive amines are described as organic bases of low molecular weight, which constitute a potential health risk. An awareness of amine levels in foods today is therefore important in relation to food safety and patient care. This review aims to emphasise the need to unify the information on the content of biogenic amines in foods and prevent patients' misunderstanding. Selective literature search for relevant publications in PubMed and other scientific data bases combined with further data from the World Wide Web on histamine and other amines content in foods. Available reference sources do not reflect a homogeneous consensus, and the variation between foods makes it impossible for dieticians to accurately estimate amines content to correctly advise patients. To achieve the goal of collecting reliable information, all methods and tools used in analytical studies should be standardised and information exposed to patients should be verified. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Combined dispersive solid-phase extraction-dispersive liquid-liquid microextraction-derivatization for gas chromatography-mass spectrometric determination of aliphatic amines on atmospheric fine particles.

PubMed

Majedi, Seyed Mohammad; Lee, Hian Kee

2017-02-24

Short-chain aliphatic amines are ubiquitous in the atmospheric environment. They play an important role in the formation and growth of atmospheric particles. As such, there is a pressing need to monitor these particle-bound compounds present at trace quantities. The present work describes an efficient, one-step microextraction technique for the preconcentration and detection of trace levels of 10 aliphatic amines on fine particles (particulate matter of 2.5μm or less (PM 2.5 )) in the atmosphere. After extraction of amines from particles in acidified water samples, carbon-based sorbents (in dispersive solid-phase extraction mode), and vortex agitation were utilized for simultaneous derivatization-extraction and dispersive liquid-liquid microextraction. The approach significantly increased the recoveries and enrichment of the amine derivatives. This one-step, combined technique is proposed for the first time. Several influential factors including type and concentration of derivatization reagent (for gas chromatographic separation), type of buffer, sample pH, types and volumes of extraction and disperser solvents, type and amount of sorbent, vortex time and temperature, desorption solvent type and volume, and salt content were investigated and optimized. Under the optimum conditions, high enrichment factors (in the range of between 307 and 382) and good reproducibility (relative standard deviations, below 7.0%, n=5) were achieved. The linearity ranged from 0.1μg/L-100μg/L, and from 0.5μg/L-100μg/L, depending on the analytes. The limits of detection were between 0.02μg/L (corresponding to ∼0.01ng/m 3 in air) and 0.09μg/L (corresponding to ∼0.04ng/m 3 in air). The developed method was successfully applied to the analysis of PM 2.5 samples collected by air sampling through polytetrafluoroethylene filters. The concentration levels of amines ranged from 1.04 to 4.16ng/m 3 in the air sampled. Copyright © 2016 Elsevier B.V. All rights reserved.

Digital Inverter Amine Sensing via Synergistic Responses by n and p Organic Semiconductors.

PubMed

Tremblay, Noah J; Jung, Byung Jun; Breysse, Patrick; Katz, Howard E

2011-11-22

Chemiresistors and sensitive OFETs have been substantially developed as cheap, scalable, and versatile sensing platforms. While new materials are expanding OFET sensing capabilities, the device architectures have changed little. Here we report higher order logic circuits utilizing OFETs sensitive to amine vapors. The circuits depend on the synergistic responses of paired p- and n-channel organic semiconductors, including an unprecedented analyte-induced current increase by the n-channel semiconductor. This represents the first step towards 'intelligent sensors' that utilize analog signal changes in sensitive OFETs to produce direct digital readouts suitable for further logic operations.

Digital Inverter Amine Sensing via Synergistic Responses by n and p Organic Semiconductors

PubMed Central

Tremblay, Noah J.; Jung, Byung Jun; Breysse, Patrick; Katz, Howard E.

2013-01-01

Chemiresistors and sensitive OFETs have been substantially developed as cheap, scalable, and versatile sensing platforms. While new materials are expanding OFET sensing capabilities, the device architectures have changed little. Here we report higher order logic circuits utilizing OFETs sensitive to amine vapors. The circuits depend on the synergistic responses of paired p- and n-channel organic semiconductors, including an unprecedented analyte-induced current increase by the n-channel semiconductor. This represents the first step towards ‘intelligent sensors’ that utilize analog signal changes in sensitive OFETs to produce direct digital readouts suitable for further logic operations. PMID:23754969

Polymorphism in R-tamsulosin (an alpha blocker): The unexpected manifestation of a sulfonamide⋯o-diethoxybenzene heterosynthon

NASA Astrophysics Data System (ADS)

Nanubolu, Jagadeesh Babu; Sridhar, Balasubramanian; Ravikumar, Krishnan

2014-12-01

A two point Nsbnd H⋯O dimer or an infinite catemer are the most preferred motifs/synthons for sulfonamide structures. Such synthons are known to be so robust that they are only disrupted in the presence of highly activated O acceptors such as pyridine-N-oxide and sulfoxide. We demonstrate in this article that a multi-point synthon offered by much weaker ethoxy O and amine N acceptors can however strongly compete and disrupt the robust sulfonamide homosynthons. This has been illustrated with the synthon analysis in three polymorphic crystal structures of R-tamsulosin, an active drug used in the treatment of Benign Prostatic Hyperplasia (BPH) and its hydrochloride salt. These crystalline solids are characterized by Single crystal X-ray diffraction (SC-XRD), powder X-ray diffraction (PXRD), Fourier Transform Infrared (FT-IR) and Raman spectroscopy. Forms I, II of the free base and hydrochloride salt crystallize in the monoclinic P21, C2, and P21 space groups respectively with two molecules in the asymmetric unit (Z‧ = 2), whereas, form III of freebase crystallize in the orthorhombic P212121 space group with Z‧ = 1. Remarkably, all four crystal structures contain a totally unexpected sulfonamide⋯o-diethoxybenzene heterosynthon. The multi-point motifs observed in polymorphs are relatively stronger than those in the hydrochloride salt because of the gauche conformation of the tamsulosin linker chain which renders an additional hydrogen bond interaction with amine N acceptor, and resemble the crown ether sulfonamide recognition pattern. Observation of this new heterosynthon offers potential scope in the design of pharmaceutical cocrystals for sulfonamide bearing drug molecules. The present study also presents a detailed hydrogen bond motif analysis in 310 primary sulfonamide structures culled from the latest version of Cambridge Structural Database (CSD). The role of various competing groups is discussed in the context of understanding the most recurring sulfonamide homo and heterosynthons.

Assessing the impact of mineralogy on our ability to detect organic salts in Gale Crater, Mars, through thermal analyses.

NASA Astrophysics Data System (ADS)

Lewis, J. M. T.; Eigenbrode, J. L.; Franz, H. B.; Sutter, B.; Niles, P. B.; McAdam, A.

2016-12-01

Organic matter present in martian sediments analyzed by the Sample Analysis at Mars (SAM) instrument suite on the Curiosity rover and in martian meteorites suggests that there may be a widespread presence of organic molecules on the surface of Mars. This organic pool may be derived from exogenous sources such as interplanetary dust particles and from indigenous processes such as volcanism, serpentinization and life, if it has ever existed on Mars. Direct detection of an ancient organic geochemical record in martian materials is challenged by two issues. First, alteration at the surface can compromise organic matter preservation. It is expected that unprotected organic compounds undergo partial oxidative diagenesis, spurred by ionizing radiation and oxidants, to metastable organic salts (e.g., iron acetate, calcium oxalate, and sodium phthalate). Such organic salts are not directly detectable by pyrolysis, producing only CO2 and CO during heating. Second, exposed organic compounds in the SAM oven, i.e., those available for reaction, are susceptible to oxidation and chlorination by perchlorates, which are thought to be ubiquitous on Mars. In order to assess whether CO2 and CO may be derived from organic salts, as opposed to combustion of other organics or mineral decomposition, a comprehensive understanding of how sample mineralogy influences their decomposition profiles is required. Simplified mineral matrices, consistent with those detected by Curiosity's Chemistry and Mineralogy instrument or inferred from SAM instrument analyses, were prepared and mixed with standards of several organic salts expected to be present on Mars. The mixtures were then analyzed under SAM-like analytical conditions. Results address the influence of iron and sulfur mineralogies and perchlorate salts on the decomposition of metastable organic salts. The results are related to the interpretation of the sub-400 °C CO2 and CO observed by SAM that may be derived from these organic salts.

Simultaneous determination of selected biogenic amines in alcoholic beverage samples by isotachophoretic and chromatographic methods.

PubMed

Jastrzębska, Aneta; Piasta, Anna; Szłyk, Edward

2014-01-01

A simple and useful method for the determination of biogenic amines in beverage samples based on isotachophoretic separation is described. The proposed procedure permitted simultaneous analysis of histamine, tyramine, cadaverine, putrescine, tryptamine, 2-phenylethylamine, spermine and spermidine. The data presented demonstrate the utility, simplicity, flexibility, sensitivity and environmentally friendly character of the proposed method. The precision of the method expressed as coefficient of variations varied from 0.1% to 5.9% for beverage samples, whereas recoveries varied from 91% to 101%. The results for the determination of biogenic amines were compared with an HPLC procedure based on a pre-column derivatisation reaction of biogenic amines with dansyl chloride. Furthermore, the derivatisation procedure was optimised by verification of concentration and pH of the buffer, the addition of organic solvents, reaction time and temperature.

Low-temperature microchip nonaqueous capillary electrophoresis of aliphatic primary amines: applications to Titan chemistry.

PubMed

Cable, Morgan L; Stockton, Amanda M; Mora, Maria F; Willis, Peter A

2013-01-15

We demonstrate microchip nonaqueous capillary electrophoresis (μNACE) analysis of primary aliphatic amines (C1-C18) in ethanol down to -20 °C as a first step in adapting microfluidic protocols for in situ analysis on Titan. To our knowledge, this is the first report of a nonaqueous separation at -20 °C on-chip. Limits of detection (LODs) ranged from 1.0 nM to 2.6 nM, and we identified several primary amines ranging in length from C2 to C16 in Titan aerosol analogue (tholin) samples; new amines were also detected in a tholin sample exposed to oxygen and liquid water. This preliminary work validates the sensitivity and efficacy of microfluidic chemical analysis of complex organics with relevance to Titan aerosols and surface deposits.

Inorganic salts interact with organic di-acids in sub-micron particles to form material with low hygroscopicity and volatility

NASA Astrophysics Data System (ADS)

Drozd, G.; Woo, J.; Häkkinen, S. A. K.; Nenes, A.; McNeill, V. F.

2013-11-01

Volatility and hygroscopicity are two key properties of organic aerosol components, and both are strongly related to chemical identity. Here we show that inorganic-organic component interactions typically not considered in atmospheric models may strongly affect aerosol volatility and hygroscopicity. In particular, bi-dentate binding of di-carboxylic acids (DCA) to soluble inorganic ions can lead to very strongly bound metal-organic complexes with largely undetermined hygroscopicity and volatility. These reactions profoundly impact particle hygroscopicity, transforming hygroscopic components into irreversibly non-hygroscopic material. While the hygroscopicities of pure salts, DCA, and DCA salts are known, the hygroscopicity of internal mixtures of hygroscopic salts and DCA, as they are typically found in the atmosphere, has not been fully characterized. We have studied the volatility of pure, dry organic salt particles and the hygroscopicity of internal mixtures of oxalic acid (OxA, the dominant DCA in the atmosphere) and a number of salts, both mono- and di-valent. The formation of very low volatility organic salts was confirmed, with minimal evaporation of oxalate salt particles below 75 °C. Dramatic increases in the CCN activation diameter for particles with divalent salts (e.g. CaCl2) and relatively small particle mass fractions of OxA indicate that standard volume additivity rules for hygroscopicity do not apply. Thus small organic compounds with high O:C are capable of forming low volatility and very low hygroscopicity particles. Given current knowledge of the formation mechanisms of OxA and M-Ox salts, surface enrichment of insoluble M-Ox salts is expected. The resulting formation of an insoluble coating of metal-oxalate salts can explain low particle hygroscopicities. The formation of particles with a hard coating could offer an alternative explanation for observations of glass-like particles with very low viscosity.

Amine-free reversible hydrogen storage in formate salts catalyzed by ruthenium pincer complex without pH control or solvent change.

PubMed

Kothandaraman, Jotheeswari; Czaun, Miklos; Goeppert, Alain; Haiges, Ralf; Jones, John-Paul; May, Robert B; Prakash, G K Surya; Olah, George A

2015-04-24

Due to the intermittent nature of most renewable energy sources, such as solar and wind, energy storage is increasingly required. Since electricity is difficult to store, hydrogen obtained by electrochemical water splitting has been proposed as an energy carrier. However, the handling and transportation of hydrogen in large quantities is in itself a challenge. We therefore present here a method for hydrogen storage based on a CO2 (HCO3 (-) )/H2 and formate equilibrium. This amine-free and efficient reversible system (>90 % yield in both directions) is catalyzed by well-defined and commercially available Ru pincer complexes. The formate dehydrogenation was triggered by simple pressure swing without requiring external pH control or the change of either the solvent or the catalyst. Up to six hydrogenation-dehydrogenation cycles were performed and the catalyst performance remained steady with high selectivity (CO free H2 /CO2 mixture was produced). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

From helical supramolecular arrays to gel-forming networks: lattice restructuring and aggregation control in peptide-based sulfamides to integrate new functional attributes.

PubMed

Raghava, Saripalli V; Srivastava, Bhartendu K; Ramshad, Kalluruttimmal; Antharjanam, Sudhadevi; Varghese, Babu; Muraleedharan, Kannoth M

2018-03-28

While supramolecular organisation is central to both crystallization and gelation, the latter is more complex considering its dynamic nature and multifactorial dependence. This makes the rational design of gelators an extremely difficult task. In this report, the assembly preference of a group of peptide-based sulfamides was modulated by making them part of an acid-amine two-component system to drive the tendency from crystallization to gelation. Here, the peptide core directed the assembly while the long-chain amines, introduced through salt-bridges, promoted layering and anisotropic development of primary aggregates. This proved to be very successful, leading to gelation of a number of solvents. Apart from this, it was possible to fine-tune their aggregation using an amphiphilic polymer like F-127 as an additive to get honey-comb-like 3D molecular architectures. These gels also proved to be excellent matrices for entrapping silver nanoparticles with superior emissive properties.

Molecularly imprinted electrochemical sensor based on amine group modified graphene covalently linked electrode for 4-nonylphenol detection.

PubMed

Chen, Hong-Jun; Zhang, Zhao-Hui; Cai, Rong; Chen, Xing; Liu, Yu-Nan; Rao, Wei; Yao, Shou-Zhuo

2013-10-15

In this work, an imprinted electrochemical sensor based on electrochemical reduced graphene covalently modified carbon electrode was developed for the determination of 4-nonylphenol (NP). An amine-terminated functional graphene oxide was covalently modified onto the electrode surface with diazonium salt reactions to improve the stability and reproducibility of the imprinted sensor. The electrochemical properties of each modified electrodes were investigated with differential pulse voltammetry (DPV). The electrochemical characteristic of the imprinted sensor was also investigated using electrochemical impedance spectroscopy (EIS) in detail. The response currents of the imprinted electrode exhibited a linear relationship toward 4-nonylphenol concentration ranging from 1.0 × 10(-11) to 1.0 × 10(-8) gm L(-1) with the detection limit of 3.5 × 10(-12) gm L(-1) (S/N=3). The fabricated electrochemical imprinted sensor was successfully applied to the detection of 4-nonylphenol in rain and lake water samples. Crown Copyright © 2013 Published by Elsevier B.V. All rights reserved.

Vitamine--vitamin. The early years of discovery.

PubMed

Rosenfeld, L

1997-04-01

In 1905, Cornelius Adrianus Pekelharing found that animals fed purified proteins, carbohydrates, fats, inorganic salts, and water would thrive only if small amounts of milk were added to the diet. He concluded that the milk contained some unrecognized substance that in very small quantities was necessary for normal growth and maintenance. In 1911, Casimir Funk isolated a concentrate from rice polishings that cured polyneuritis in pigeons. He named the concentrate "vitamine" because it appeared to be vital to life and because it was probably an amine. Although the concentrate and other "accessory food substances" were not amines, the name stuck, but the final "e" was dropped. In 1913 two groups discovered a "fat-soluble" accessory food substance. Initially believed to be a single vitamin, two separate factors were involved. One, effective against xerophthalmia, was named vitamin A; the other, effective against rickets, was named vitamin D. The factor that prevented scurvy was isolated in 1928. Known as "water-soluble C," it was renamed ascorbic acid.

Time-resolved measurement of intramolecular photoinduced electron transfer processes in perylene diimides (Conference Presentation)

NASA Astrophysics Data System (ADS)

Döring, Robin Carl; Baal, Eduard; Sundermeyer, Jörg; Chatterjee, Sangam

2017-02-01

Perylene-3,4,9,10-tetracarboxylic acid (PTCDA) and respective derivatives (e.g. perylene diimide - PDI) are widely used as dyes but also for device applications such as organic field effect transistors or in organic photovoltaics. Due to their intrinsically high quantum efficiencies they are also used as spectroscopic standards. One major drawback of these materials is their low solubility in organic solvents which can be addressed by long alkyl substitutions. When introducing a tertiary amine into the molecule a mechanism known as photoinduced electron transfer (PET) can occur. Here, following an optically excited HOMO-LUMO transition of the core, an electron from the electron lone pair of the amine is transferred to the HOMO of the perylene core. Hence, radiative recombination is disallowed and photoluminescence effectively quenched. Here, we perform a systematic study of the distance dependence of the PET by introducing alkyle groups as spacer units between PDI core and the tertiary amine. Dynamics of the PET are extracted from ultrafast time-resolved photoluminescence measurement data. A rate equation model, simulating a three level system, reveals rate constant of the back electron transfer, otherwise not accessible with our experimental methods. Assuming a Marcus model of electron transfer, electronic coupling strength between the electronic states involved in the respective transitions can be calculated. In addition to the distance dependence, the effects of protonation and methylation of the the tertiary amine units are studied.

PROCESS FOR EXTRACTING NEPTUNIUM AND PLUTONIUM FROM NITRIC ACID SOLUTIONS OF SAME CONTAINING URANYL NITRATE WITH A TERTIARY AMINE

DOEpatents

Sheppard, J.C.

1962-07-31

A process of selectively extracting plutonium nitrate and neptunium nitrate with an organic solution of a tertiary amine, away from uranyl nitrate present in an aqueous solution in a maximum concentration of 1M is described. The nitric acid concentration is adjusted to about 4M and nitrous acid is added prior to extraction. (AEC)

Use of portable analytical methods to determine the stoichiometry of reaction for hexahydrotriazine-based hydrogen sulfide scavenger operations.

PubMed

Taylor, Grahame N; Matherly, Ron

2014-05-20

During the reaction between 1,3,5-tris(2-hydroxyethyl)hexahydro-s-triazine and hydrogen sulphide, the principle by-product is the organic sulphide 5-(2-hydroxyethyl)dithiazine. It can be determined by a novel, portable, field-capable ion mobility spectrometry method described herein and enables the "degree spent" to be determined. Dependant upon the level of carbon dioxide in the produced gas, a mixture of ethanolaminium bicarbonate and ethanolamine bisulphide is also produced. Using a field capable spectrophotometric method the level of inorganic sulphide can be determined, thus allowing the ethanolaminium bisulphide concentration to be calculated. Provided the fluid is only partially spent, and there is some unreacted 1,3,5-tris(2-hydroxyethyl)hexahydro-s-triazine remaining; the only source of inorganic sulphide is the amine salt. From a knowledge of the original fluid concentration, the combination of these two methods allows the effective stoichiometry, or observed molar reaction proportions between 1,3,5-tris(2-hydroxyethyl)hexahydro-s-triazine and hydrogen sulphide, to be measured for a specific field location.

[Effect of Long-Term Fertilization on Organic Nitrogen Functional Groups in Black Soil as Revealed by Synchrotron-Based X-Ray Absorption Near-Edge Structure Spectroscopy].

PubMed

Li, Hui; Gao, Qiang; Wang, Shuai; Zhu, Ping; Zhang, Jin-jing; Zhao, Yi-dong

2015-07-01

Nitrogen (N) is a common limiting nutrient in crop production. The N content of soil has been used as an important soil fertility index. Organic N is the major form of N in soil. In most agricultural surface soils, more than 90% of total N occurs in organic forms. Therefore, understanding the compositional characteristics of soil organic N functional groups can provide the scientific basis for formulating the reasonable farmland management strategies. Synchrotron radiation soft X-ray absorption near-edge structure (N K-edge XANES) spectroscopy is the most powerful tool to characterize in situ organic N functional groups compositions in soil. However, to our most knowledge, no studies have been conducted to examine the organic N functional groups compositions of soil using N K-edge XANES spectroscopy under long-term fertilization practices. Based on a long-term field experiment (started in 1990) in a black soil (Gongzhuling, Northeast China), we investigated the differences in organic N functional groups compositions in bulk soil and clay-size soil fraction among fertilization patterns using synchrotron-based N K- edge XANES spectroscopy. Composite soil samples (0-20 cm) were collected in 2008. The present study included six treatments: farmland fallow (FALL), no-fertilization control (CK), chemical nitrogen, phosphorus, and potassium fertilization (NPK), NPK in combination with organic manure (NPKM), 1.5 times of NPKM (1.5 NPKM), and NPK in combination with maize straw (NPKS). The results showed that N K-edge XANES spectra of all the treatments under study exhibited characteristic absorption peaks in the ranges of 401.2-401.6 and 402.7-403.1 eV, which were assigned as amides/amine-N and pyrrole-N, respectively. These characteristic absorption peaks were more obvious in clay-size soil fraction than in bulk soil. The results obtained from the semi-quantitative analysis of N K-edge XANES spectra indicated that the relative proportion of amides/amine-N was the highest in both bulk soil and clay-size soil fraction, and it was the most major forms in soil organic nitrogen functional groups. Compared with the FALL treatment, the relative proportion of amide/amine-N was lower whereas that of Pyrrole-N was higher in the CK treatment. In the treatments with combined chemical fertilizers and organic manure, the relative proportion of amide/amine-N decreased with increasing application rates of organic manure, while that of Pyrrole-N had an opposite trend. In bulk soil, the relative proportion of amide/amine-N was the highest for the NPKS treatment than for the other treatments. On the other hand, the relative proportion of nitrile/aromatic-N was the highest for the Fallow treatment than for the other treatments in clay-size soil fraction. It is feasible to use N K-edge XANES spectroscopy for characterizing in situ the changes of organic N functional groups in soil under different fertilization practices.

Ethyl acetate as an acyl donor in the continuous flow kinetic resolution of (±)-1-phenylethylamine catalyzed by lipases.

PubMed

de Miranda, Amanda S; Miranda, Leandro S M; de Souza, Rodrigo O M A

2013-05-28

The synthesis of chiral amines is still a challenge for organic synthesis since optically pure amines are of great importance for the pharmaceutical and agrochemical industries. Among all the methodologies developed until now, chemoenzymatic dynamic kinetic resolution has proven to be useful for the preparation of enantioenriched primary chiral amines. In our continuous efforts toward the development of a continuous flow process, herein we report our results on the continuous flow kinetic resolution of (±)-1-phenylethylamine leading to the desired products with high enantiomeric ratios (>200) and short residence times (40 minutes) using ethyl acetate as the acyl donor.

Toxicity of Cúspide 480SL® spray mixture formulation of glyphosate to aquatic organisms.

PubMed

Currie, Zachary; Prosser, Ryan S; Rodriguez-Gil, Jose Luis; Mahon, Kim; Poirier, Dave; Solomon, Keith R

2015-05-01

In 2011, an alternative formulation of glyphosate (Cúspide 480SL®) was chosen to replace Roundup-SL®, Fuete-SL®, and Gly-41® for the control of Erythroxylum coca, the source of cocaine, in Colombia. Cúspide 480SL contains the active ingredient glyphosate isopropylamine (IPA) salt, which is the same active ingredient used in previous formulations. However, Cúspide 480SL contains an alkyl polyglycoside surfactant rather than the polyethoxylated tallow amine (POEA) surfactant used in other formulations and known to be more toxic to nonprimary producing aquatic organisms than glyphosate itself. An adjuvant, Cosmo-Flux F411, and water also are added to the spray mixture before application. Aquatic ecosystems adjacent to the target coca fields might be exposed to the spray mix, placing aquatic organisms at risk. Because no toxicity data were available for spray mixture on aquatic organisms, acute toxicity tests were conducted on aquatic plants, invertebrates, and fish, by using the Cúspide 480SL spray mix as described on the label. Based on the median effective concentration (EC50) values for similar organisms, the spray mixture was less toxic to aquatic organisms than formulations previously used for the control of coca (i.e., Roundup-SL, Fuete-SL, and Gly-41). A physical effect induced by Cosmo-Flux F411 was observed in Daphnia magna, Ceriodaphnia dubia, and Hyalella azteca, causing the invertebrates to be trapped in an oily film that was present at the surface of the water. However, a hazard assessment for the Cúspide 480SL spray mix, using estimated worst-case exposure scenario concentrations and EC50 values from the toxicity tests, indicated de minimis hazard for the tested aquatic animals, with hazard quotients all <1. © 2015 SETAC.

Quantification of Stereochemical Communication in Metal-Organic Assemblies.

PubMed

Castilla, Ana M; Miller, Mark A; Nitschke, Jonathan R; Smulders, Maarten M J

2016-08-26

The derivation and application of a statistical mechanical model to quantify stereochemical communication in metal-organic assemblies is reported. The factors affecting the stereochemical communication within and between the metal stereocenters of the assemblies were experimentally studied by optical spectroscopy and analyzed in terms of a free energy penalty per "incorrect" amine enantiomer incorporated, and a free energy of coupling between stereocenters. These intra- and inter-vertex coupling constants are used to track the degree of stereochemical communication across a range of metal-organic assemblies (employing different ligands, peripheral amines, and metals); temperature-dependent equilibria between diastereomeric cages are also quantified. The model thus provides a unified understanding of the factors that shape the chirotopic void spaces enclosed by metal-organic container molecules. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Inorganic salts interact with oxalic acid in submicron particles to form material with low hygroscopicity and volatility

NASA Astrophysics Data System (ADS)

Drozd, G.; Woo, J.; Häkkinen, S. A. K.; Nenes, A.; McNeill, V. F.

2014-05-01

Volatility and hygroscopicity are two key properties of organic aerosol components, and both are strongly related to chemical identity. While the hygroscopicities of pure salts, di-carboxylic acids (DCA), and DCA salts are known, the hygroscopicity of internal mixtures of these components, as they are typically found in the atmosphere, has not been fully characterized. Here we show that inorganic-organic component interactions typically not considered in atmospheric models can lead to very strongly bound metal-organic complexes and greatly affect aerosol volatility and hygroscopicity; in particular, the bi-dentate binding of DCA to soluble inorganic ions. We have studied the volatility of pure, dry organic salt particles and the hygroscopicity of internal mixtures of oxalic acid (OxA, the dominant DCA in the atmosphere) and a number of salts, both mono- and di-valent. The formation of very low volatility organic salts was confirmed, with minimal evaporation of oxalate salt particles below 75 °C. Dramatic increases in the cloud condensation nuclei (CCN) activation diameter for particles with di-valent salts (e.g., CaCl2) and relatively small particle volume fractions of OxA indicate that standard volume additivity rules for hygroscopicity do not apply. Thus small organic compounds with high O : C ratios are capable of forming low-volatility and very low hygroscopicity particles. Given current knowledge of the formation mechanisms of OxA and M-Ox salts, surface enrichment of insoluble M-Ox salts is expected. The resulting formation of an insoluble coating of metal-oxalate salts can explain low-particle hygroscopicities. The formation of particles with a hard coating could offer an alternative explanation for observations of glass-like particles without the need for a phase transition.

Protecting‐Group‐Free Amidation of Amino Acids using Lewis Acid Catalysts

PubMed Central

Sabatini, Marco T.; Karaluka, Valerija; Lanigan, Rachel M.; Boulton, Lee T.; Badland, Matthew

2018-01-01

Abstract Amidation of unprotected amino acids has been investigated using a variety of ‘classical“ coupling reagents, stoichiometric or catalytic group(IV) metal salts, and boron Lewis acids. The scope of the reaction was explored through the attempted synthesis of amides derived from twenty natural, and several unnatural, amino acids, as well as a wide selection of primary and secondary amines. The study also examines the synthesis of medicinally relevant compounds, and the scalability of this direct amidation approach. Finally, we provide insight into the chemoselectivity observed in these reactions. PMID:29505683

(2SR,3RS)-Benz­yl[4-chloro-1-(4-chloro­phen­yl)-1-methoxy­carbon­yl-2-but­yl]­ammonium chloride

PubMed Central

Kaupang, Åsmund; Bolsønes, Marianne; Gamadeku, Thywill; Hansen, Tore; Hennum, Martin Johanson; Görbitz, Carl Henrik

2008-01-01

In the racemic hydro­chloride salt of the title ester, C19H22Cl2NO2 +·Cl−, the penta­noic acid chain shows a mixture of trans and gauche orientations to give an overall helical conformation. The dihedral angle between the two aromatic rings is 26.11 (10)°. The charged secondary amine function participates in two N—H⋯Cl hydrogen bonds. PMID:21201230

IR spectroscopic study of the chemical composition of epiphytic lichens

NASA Astrophysics Data System (ADS)

Meysurova, A. F.; Khizhnyak, S. D.; Pakhomov, P. M.

2011-11-01

Changes in the chemical composition of lichens exposed to pollutants are investigated by means of FTIR spectroscopy. According to model experiments, alkyl nitrates, ammonium salts, amines, and sulfones develop in the lichen thallus through the action of ammonia and nitric and sulfuric acids. Spectroscopic data of modeling experiments enabled nitrogen- and sulfur-containing substances to be identified as the main air pollutants in the vicinity of a pig-breeding complex and information to be obtained on the content of the pollutants and their impact on the lichens.

Two-step iron(0)-mediated N-demethylation of N-methyl alkaloids.

PubMed

Kok, Gaik B; Pye, Cory C; Singer, Robert D; Scammells, Peter J

2010-07-16

A mild and simple two-step Fe(0)-mediated N-demethylation of a number of tertiary N-methyl alkaloids is described. The tertiary N-methylamine is first oxidized to the corresponding N-oxide, which is isolated as the hydrochloride salt. Subsequent treatment of the N-oxide hydrochloride with iron powder readily provides the N-demethylated amine. Representative substrates include a number of opiate and tropane alkaloids. Key intermediates in the synthesis of semisynthetic 14-hydroxy pharmaceutical opiates such as oxycodone and oxymorphone are also readily N-demethylated using this method.

Effect of Sodium Sulfate, Ammonium Chloride, Ammonium Nitrate, and Salt Mixtures on Aqueous Phase Partitioning of Organic Compounds.

PubMed

Wang, Chen; Lei, Ying Duan; Wania, Frank

2016-12-06

Dissolved inorganic salts influence the partitioning of organic compounds into the aqueous phase. This influence is especially significant in atmospheric aerosol, which usually contains large amounts of ions, including sodium, ammonium, chloride, sulfate, and nitrate. However, empirical data on this salt effect are very sparse. Here, the partitioning of numerous organic compounds into solutions of Na 2 SO 4 , NH 4 Cl, and NH 4 NO 3 was measured and compared with existing data for NaCl and (NH 4 ) 2 SO 4 . Salt mixtures were also tested to establish whether the salt effect is additive. In general, the salt effect showed a decreasing trend of Na 2 SO 4 > (NH) 2 SO 4 > NaCl > NH 4 Cl > NH 4 NO 3 for the studied organic compounds, implying the following relative strength of the salt effect of individual anions: SO 4 2- > Cl - > NO 3 - and of cations: Na + > NH 4 + . The salt effect of different salts is moderately correlated. Predictive models for the salt effect were developed based on the experimental data. The experimental data indicate that the salt effect of mixtures may not be entirely additive. However, the deviation from additivity, if it exists, is small. Data of very high quality are required to establish whether the effect of constituent ions or salts is additive or not.

In situ chemical composition measurement of individual cloud residue particles at a mountain site, southern China

NASA Astrophysics Data System (ADS)

Lin, Qinhao; Zhang, Guohua; Peng, Long; Bi, Xinhui; Wang, Xinming; Brechtel, Fred J.; Li, Mei; Chen, Duohong; Peng, Ping'an; Sheng, Guoying; Zhou, Zhen

2017-07-01

To investigate how atmospheric aerosol particles interact with chemical composition of cloud droplets, a ground-based counterflow virtual impactor (GCVI) coupled with a real-time single-particle aerosol mass spectrometer (SPAMS) was used to assess the chemical composition and mixing state of individual cloud residue particles in the Nanling Mountains (1690 m a. s. l. ), southern China, in January 2016. The cloud residues were classified into nine particle types: aged elemental carbon (EC), potassium-rich (K-rich), amine, dust, Pb, Fe, organic carbon (OC), sodium-rich (Na-rich) and Other. The largest fraction of the total cloud residues was the aged EC type (49.3 %), followed by the K-rich type (33.9 %). Abundant aged EC cloud residues that mixed internally with inorganic salts were found in air masses from northerly polluted areas. The number fraction (NF) of the K-rich cloud residues increased within southwesterly air masses from fire activities in Southeast Asia. When air masses changed from northerly polluted areas to southwesterly ocean and livestock areas, the amine particles increased from 0.2 to 15.1 % of the total cloud residues. The dust, Fe, Pb, Na-rich and OC particle types had a low contribution (0.5-4.1 %) to the total cloud residues. Higher fraction of nitrate (88-89 %) was found in the dust and Na-rich cloud residues relative to sulfate (41-42 %) and ammonium (15-23 %). Higher intensity of nitrate was found in the cloud residues relative to the ambient particles. Compared with nonactivated particles, nitrate intensity decreased in all cloud residues except for dust type. To our knowledge, this study is the first report on in situ observation of the chemical composition and mixing state of individual cloud residue particles in China.

Study of interaction and adsorption of aromatic amines by manganese oxides and their role in chemical evolution

NASA Astrophysics Data System (ADS)

Bhushan, Brij; Nayak, Arunima; Kamaluddin

2017-04-01

The role of manganese oxides in concentrating organic moieties and offering catalytic activity for prebiotic reactions is investigated by studying their interaction with different aromatic amines such as aniline, p-chloroaniline, p-toluidine and p-anisidine. For all amines, metal oxides showed highest adsorption at neutral pH. The order of their adsorption capacity and affinity as revealed by the Langmuir constants was found to be manganosite (MnO) > bixbyite (Mn2O3) > hausmannite (Mn3O4) > and pyrolusite (MnO2). At alkaline pH, these manganese oxides offered their surfaces for oxidation of amines to form coloured oligomers. Analysis of the oxidation products by gas chromatography-mass spectrometry showed the formation of a dimer from p-anisidine and p-chloroaniline, while a trimer and tetramer is formed from p-toluidine and aniline, respectively. A reaction mechanism is proposed for the formation of the oligomers. While field-emission scanning electron microscopic studies confirm the binding phenomenon, the Fourier transform infrared spectroscopy analysis suggests that the mechanism of binding of amines on the manganese oxides was primarily electrostatic. The adsorption behaviour of the studied aromatic amines followed the order: p-anisidine > p-toluidine > aniline > p-chloroaniline, which is related to the basicities and structure of the amines. Our studies confirmed the significance of the role of manganese oxides in prebiotic chemistry.

A rapid detection method for policy-sensitive amines real-time supervision.

PubMed

Zhang, Haixu; Shu, Jinian; Yang, Bo; Zhang, Peng; Ma, Pengkun

2018-02-01

Many organic amines that comprise a benzene ring are policy-sensitive because of their toxicity and links to social harm. However, to date, detection of such compounds mainly relies on offline methods. This study proposes an online pptv (parts per trillion by volume) level of detection method for amines, using the recently-built vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) combined with a new doping technique. Thus, the dichloromethane doping-assisted photoionization mass spectra of aniline, benzylamine, phenethylamine, amphetamine, and their structural isomers were recorded. The dominant characteristic mass peaks for all amines are those afforded by protonated amines and the amino radical-loss. The signal intensities of the amines were enhanced by 60-130 times compared to those recorded without doping assistance. Under 10s detection time, the sensitivities of aniline and benzylamine in the gas phase were determined as 4.0 and 2.7 countspptv -1 , with limits of detection (LODs) of 36 and 22 pptv, respectively. Notably, the detection efficiency of this method can be tenfold better in future applications since the ion transmission efficiency of the mass spectrometer was intentionally reduced to ~ 10% in this study. Therefore, dichloromethane doping-assisted photoionization mass spectrometry has proven to be a highly promising on-line approach to amine detection in environmental and judicial supervision and shows great potential for application in the biological field. Copyright © 2017 Elsevier B.V. All rights reserved.

DNA compaction by poly (amido amine) dendrimers of ammonia cored and ethylene diamine cored

NASA Astrophysics Data System (ADS)

Qamhieh, K.; Al-Shawwa, J.

2017-06-01

The complexes build-up of DNA and soft particles poly amidoamine (PAMAM) dendrimers of ammonia cored of generations (G1-G6) and ethylenediamine cored of generations (G1-G10) have been studied, using a new theoretical model developed by Qamhieh and coworkers. The model describes the interaction between linear polyelectrolyte (LPE) chain and ion-penetrable spheres. Many factors affecting LPE/dendrimer complex have been investigated such as dendrimer generation, the Bjerrum length, salt concentration, and rigidity of the LPE chain represented by the persistence length. It is found that the wrapping chain length around dendrimer increases by increasing dendrimer`s generation, Bjerrum length, and salt concentration, while decreases by increasing the persistence length of the LPE chain. Also we can conclude that the wrapping length of LPE chain around ethylenediamine cored dendrimers is larger than its length around ammonia cored dendrimers.

Carboxylate modified porous graphitic carbon: a new class of hydrophilic interaction liquid chromatography phases.

PubMed

Wahab, M Farooq; Ibrahim, Mohammed E A; Lucy, Charles A

2013-06-18

Stationary phases for hydrophilic interaction liquid chromatography (HILIC) are predominantly based on silica and polymer supports. We present porous graphitic carbon particles with covalently attached carboxylic acid groups (carboxylate-PGC) as a new HILIC stationary phase. PGC particles were modified by adsorbing the diazonium salt of 4-aminobenzoic acid onto the PGC, followed by reduction of the adsorbed salt with sodium borohydride. The newly developed carboxylate-PGC phase exhibits different selectivity than that of 35 HPLC columns, including bare silica, zwitterionic, amine, reversed, and unmodified PGC phases. Carboxylate-PGC is stable from pH 2.0 to 12.6, yielding reproducible retention even at pH 12.6. Characterization of the new phase is presented by X-ray photoelectron spectroscopy, thermogravimetry, zeta potentials, and elemental analysis. The chromatographic performance of carboxylate-PGC as a HILIC phase is illustrated by separations of carboxylic acids, nucleotides, phenols, and amino acids.

Plants and microbes assisted selenium nanoparticles: characterization and application

PubMed Central

2014-01-01

Selenium is an essential trace element and is an essential component of many enzymes without which they become inactive. The Se nanoparticles of varying shape and size may be synthesized from Se salts especially selenite and selenates in presence of reducing agents such as proteins, phenols, alcohols and amines. These biomolecules can be used to reduce Se salts in vitro but the byproducts released in the environment may be hazardous to flora and fauna. In this review, therefore, we analysed in depth, the biogenic synthesis of Se nanoparticles, their characterization and transformation into t- Se, m-Se, Se-nanoballs, Se-nanowires and Se-hollow spheres in an innocuous way preventing the environment from pollution. Their shape, size, FTIR, UV–vis, Raman spectra, SEM, TEM images and XRD pattern have been analysed. The weak forces involved in aggregation and transformation of one nano structure into the other have been carefully resolved. PMID:25128031

Plants and microbes assisted selenium nanoparticles: characterization and application.

PubMed

Husen, Azamal; Siddiqi, Khwaja Salahuddin

2014-08-16

Selenium is an essential trace element and is an essential component of many enzymes without which they become inactive. The Se nanoparticles of varying shape and size may be synthesized from Se salts especially selenite and selenates in presence of reducing agents such as proteins, phenols, alcohols and amines. These biomolecules can be used to reduce Se salts in vitro but the byproducts released in the environment may be hazardous to flora and fauna. In this review, therefore, we analysed in depth, the biogenic synthesis of Se nanoparticles, their characterization and transformation into t- Se, m-Se, Se-nanoballs, Se-nanowires and Se-hollow spheres in an innocuous way preventing the environment from pollution. Their shape, size, FTIR, UV-vis, Raman spectra, SEM, TEM images and XRD pattern have been analysed. The weak forces involved in aggregation and transformation of one nano structure into the other have been carefully resolved.

SEPARATION OF INORGANIC SALTS FROM ORGANIC SOLUTIONS

DOEpatents

Katzin, L.I.; Sullivan, J.C.

1958-06-24

A process is described for recovering the nitrates of uranium and plutonium from solution in oxygen-containing organic solvents such as ketones or ethers. The solution of such salts dissolved in an oxygen-containing organic compound is contacted with an ion exchange resin whereby sorption of the entire salt on the resin takes place and then the salt-depleted liquid and the resin are separated from each other. The reaction seems to be based on an anion formation of the entire salt by complexing with the anion of the resin. Strong base or quaternary ammonium type resins can be used successfully in this process.

Fine-Tuning of the Carbon Dioxide Capture Capability of Diamine-Grafted Metal-Organic Framework Adsorbents Through Amine Functionalization.

PubMed

Jo, Hyuna; Lee, Woo Ram; Kim, Nam Woo; Jung, Hyun; Lim, Kwang Soo; Kim, Jeong Eun; Kang, Dong Won; Lee, Hanyeong; Hiremath, Vishwanath; Seo, Jeong Gil; Jin, Hailian; Moon, Dohyun; Han, Sang Soo; Hong, Chang Seop

2017-02-08

A combined sonication and microwave irradiation procedure provides the most effective functionalization of ethylenediamine (en) and branched primary diamines of 1-methylethylenediamine (men) and 1,1-dimethylethylenediamine (den) onto the open metal sites of Mg 2 (dobpdc) (1). The CO 2 capacities of the advanced adsorbents 1-en and 1-men under simulated flue gas conditions are 19 wt % and 17.4 wt %, respectively, which are the highest values reported among amine-functionalized metal-organic frameworks (MOFs) to date. Moreover, 1-den exhibits both a significant working capacity (12.2 wt %) and superb CO 2 uptake (11 wt %) at 3 % CO 2 . Additionally, this framework showcases the superior recyclability; ultrahigh stability after exposure to O 2 , moisture, and SO 2 ; and exceptional CO 2 adsorption capacity under humid conditions, which are unprecedented among MOFs. We also elucidate that the performance of CO 2 adsorption can be controlled by the structure of the diamine ligands grafted such as the number of amine end groups or the presence of side groups, which provides the first systematic and comprehensive demonstration of fine-tuning of CO 2 uptake capability using different amines. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enhanced amine and amino acid analysis using Pacific Blue and the Mars Organic Analyzer microchip capillary electrophoresis system.

PubMed

Chiesl, Thomas N; Chu, Wai K; Stockton, Amanda M; Amashukeli, Xenia; Grunthaner, Frank; Mathies, Richard A

2009-04-01

The fluorescent amine reactive probe Pacific Blue succinimidyl ester (PB) is used for the detection of trace amounts of amines and amino acids by microchip capillary electrophoresis on the Mars Organic Analyzer (MOA). The spectral and chemical properties of PB provide a 200-fold increase in sensitivity and improved resolution compared to fluorescamine derivatization. With the use of cross injection and PB labeling, the MOA detected amino acids at concentrations as low as 75 pM (sub-parts-per-trillion). Micellar electrokinetic chromatography (MEKC) which separates PB-labeled amino acids by their hydrophobicity is also demonstrated. The optimized MEKC conditions (45 mM CHAPSO, pH 6 at 5 degrees C) effectively separated amines and 25 amino acids with enantiomeric resolution of alanine, serine, and citrulline. Samples from the Yungay Hills region in the Atacama Desert, Chile, and from the Murchison meteorite are successfully analyzed using both techniques, and amino acids are found in the parts-per-billion range. Abiotic amino acids such as beta-alanine and epsilon-aminocaprioc acid are detected along with several neutral and acidic amino acids in the Murchison sample. The Atacama Desert sample is found to contain homochiral L-alanine and L-serine indicating the presence of extant or recently extinct life.

Contribution of inorganic and organic components to sorption of neutral and ionizable pharmaceuticals by sediment/soil.

PubMed

Yamamoto, Hiroshi; Takemoto, Kohei; Tamura, Ikumi; Shin-Oka, Norihiro; Nakano, Takahiro; Nishida, Masayo; Honda, Yuta; Moriguchi, Shigemi; Nakamura, Yudai

2018-03-01

Our previous study showed that the sorption coefficient of certain polar pharmaceuticals to river sediment, especially particular amines, was unexpectedly high. Thus, we conducted sorption experiments of selected polar pharmaceuticals and pyrene derivatives, including amines, carboxylic acids, and neutral compounds, to model clay minerals, i.e., montmorillonite and kaolin, in addition to silica sands and humic substances. The contribution of each component was roughly estimated by simple fractionation of the individual sorption coefficients. Relatively high sorption coefficients (K d values) were found, especially for amines on clay minerals, which suggest that electrochemical affinity may play an important role. The estimated contribution percentage suggests a relatively large contribution from inorganic constituents, such as clay minerals, for silt loam soil; in contrast, organic components predominantly contribute for sandy river sediments. These findings could be the key to understanding not only the fate and transport but also bioavailability and environmental risks of pharmaceuticals, which are mostly polar and/or ionizable.

Synthesis of Ureas from CO2.

PubMed

Wang, Hua; Xin, Zhuo; Li, Yuehui

2017-04-01

Ureas are an important class of bioactive organic compounds in organic chemistry and exist widely in natural products, agricultural pesticides, uron herbicides, pharmaceuticals. Even though urea itself has been synthesized from CO 2 and ammonia for a long time, the selective and efficient synthesis of substituted ureas is still challenging due to the difficulty of dehydration processes. Efficient and economic fixation of CO 2 is of great importance in solving the problems of resource shortages, environmental issues, global warming, etc. During recent decades, chemists have developed different catalytic systems to synthesize ureas from CO 2 and amines. Herein, we focus on catalytic synthesis of ureas using CO 2 and amines.

The World Hypertension League: where now and where to in salt reduction

PubMed Central

Lackland, Daniel T.; Lisheng, Liu; Zhang, Xin-Hua; Nilsson, Peter M.; Niebylski, Mark L.

2015-01-01

High dietary salt is a leading risk for death and disability largely by causing increased blood pressure. Other associated health risks include gastric and renal cell cancers, osteoporosis, renal stones, and increased disease activity in multiple sclerosis, headache, increased body fat and Meniere’s disease. The World Hypertension League (WHL) has prioritized advocacy for salt reduction. WHL resources and actions include a non-governmental organization policy statement, dietary salt fact sheet, development of standardized nomenclature, call for quality research, collaboration in a weekly salt science update, development of a process to set recommended dietary salt research standards and regular literature reviews, development of adoptable power point slide sets to support WHL positions and resources, and critic of weak research studies on dietary salt. The WHL plans to continue to work with multiple governmental and non-governmental organizations to promote dietary salt reduction towards the World Health Organization (WHO) recommendations. PMID:26090335

Site-selective arene C-H amination via photoredox catalysis.

PubMed

Romero, Nathan A; Margrey, Kaila A; Tay, Nicholas E; Nicewicz, David A

2015-09-18

Over the past several decades, organometallic cross-coupling chemistry has developed into one of the most reliable approaches to assemble complex aromatic compounds from preoxidized starting materials. More recently, transition metal-catalyzed carbon-hydrogen activation has circumvented the need for preoxidized starting materials, but this approach is limited by a lack of practical amination protocols. Here, we present a blueprint for aromatic carbon-hydrogen functionalization via photoredox catalysis and describe the utility of this strategy for arene amination. An organic photoredox-based catalyst system, consisting of an acridinium photooxidant and a nitroxyl radical, promotes site-selective amination of a variety of simple and complex aromatics with heteroaromatic azoles of interest in pharmaceutical research. We also describe the atom-economical use of ammonia to form anilines, without the need for prefunctionalization of the aromatic component. Copyright © 2015, American Association for the Advancement of Science.

Electrodialysis-based separation process for salt recovery and recycling from waste water

DOEpatents

Tsai, S.P.

1997-07-08

A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants-containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid. 6 figs.

Electrodialysis-based separation process for salt recovery and recycling from waste water

DOEpatents

Tsai, Shih-Perng

1997-01-01

A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid.

General Dialdehyde Click Chemistry for Amine Bioconjugation.

PubMed

Elahipanah, Sina; O'Brien, Paul J; Rogozhnikov, Dmitry; Yousaf, Muhammad N

2017-05-17

The development of methods for conjugating a range of molecules to primary amine functional groups has revolutionized the fields of chemistry, biology, and material science. The primary amine is a key functional group and one of the most important nucleophiles and bases used in all of synthetic chemistry. Therefore, tremendous interest in the synthesis of molecules containing primary amines and strategies to devise chemical reactions to react with primary amines has been at the core of chemical research. In particular, primary amines are a ubiquitous functional group found in biological systems as free amino acids, as key side chain lysines in proteins, and in signaling molecules and metabolites and are also present in many natural product classes. Due to its abundance, the primary amine is the most convenient functional group handle in molecules for ligation to other molecules for a broad range of applications that impact all scientific fields. Because of the primary amine's central importance in synthetic chemistry, acid-base chemistry, redox chemistry, and biology, many methods have been developed to efficiently react with primary amines, including activated carboxylic acids, isothiocyanates, Michael addition type systems, and reaction with ketones or aldehydes followed by in situ reductive amination. Herein, we introduce a new traceless, high-yield, fast click-chemistry method based on the rapid and efficient trapping of amine groups via a functionalized dialdehyde group. The click reaction occurs in mild conditions in organic solvents or aqueous media and proceeds in high yield, and the starting dialdehyde reagent and resulting dialdehyde click conjugates are stable. Moreover, no catalyst or dialdehyde-activating group is required, and the only byproduct is water. The initial dialdehyde and the resulting conjugate are both straightforward to characterize, and the reaction proceeds with high atom economy. To demonstrate the broad scope of this new click-conjugation strategy, we designed a straightforward scheme to synthesize a suite of dialdehyde reagents. The dialdehyde molecules were used for applications in cell-surface engineering and for tailoring surfaces for material science applications. We anticipate the broad utility of the general dialdehyde click chemistry to primary amines in all areas of chemical research, ranging from polymers and bioconjugation to material science and nanoscience.

Using parahydrogen to hyperpolarize amines, amides, carboxylic acids, alcohols, phosphates, and carbonates

PubMed Central

Iali, Wissam; Rayner, Peter J.; Duckett, Simon B.

2018-01-01

Hyperpolarization turns weak nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) responses into strong signals, so normally impractical measurements are possible. We use parahydrogen to rapidly hyperpolarize appropriate 1H, 13C, 15N, and 31P responses of analytes (such as NH3) and important amines (such as phenylethylamine), amides (such as acetamide, urea, and methacrylamide), alcohols spanning methanol through octanol and glucose, the sodium salts of carboxylic acids (such as acetic acid and pyruvic acid), sodium phosphate, disodium adenosine 5′-triphosphate, and sodium hydrogen carbonate. The associated signal gains are used to demonstrate that it is possible to collect informative single-shot NMR spectra of these analytes in seconds at the micromole level in a 9.4-T observation field. To achieve these wide-ranging signal gains, we first use the signal amplification by reversible exchange (SABRE) process to hyperpolarize an amine or ammonia and then use their exchangeable NH protons to relay polarization into the analyte without changing its identity. We found that the 1H signal gains reach as high as 650-fold per proton, whereas for 13C, the corresponding signal gains achieved in a 1H-13C refocused insensitive nuclei enhanced by polarization transfer (INEPT) experiment exceed 570-fold and those in a direct-detected 13C measurement exceed 400-fold. Thirty-one examples are described to demonstrate the applicability of this technique. PMID:29326984

Modulation of biogenic amines content by poly(propylene imine) dendrimers in rats.

PubMed

Ciepluch, Karol; Ziemba, Barbara; Janaszewska, Anna; Appelhans, Dietmar; Klajnert, Barbara; Bryszewska, Maria; Fogel, Wiesława Agnieszka

2012-09-01

Biogenic amines and polyamines participate in all vital organism functions, their levels being important function determinants. Studies were performed to check whether repeated administration of poly(propylene imine) (PPI) dendrimers, synthetic macromolecules with diaminobutane core, and peripheral primary amine groups, may influence the endogenous level of amines, as represented by the two of them: spermidine, a natural derivative of diaminobutane, and histamine. The experiment was carried out on Wistar rats. Fourth generation PPI dendrimer, as well as maltotriose-modified fourth generation PPI dendrimers with (a) cationic open sugar shell and (b) neutral dense sugar shell that possess a higher biocompatibility, was used. Applying the combination of column chromatography on Cellex P and spectrofluorimetric assays of o-phthaldialdehyde, the final amine condensation products were employed to analyze tissue spermidine and histamine outside the central nervous system. Furthermore, radioenzymatic assay was used to measure histamine levels in the brain. The obtained results indicate that in some tissues, the endogenous concentrations of histamine and spermidine may be affected by dendrimers depending on their dose and type of dendrimers.

Preparation of guar gum scaffold film grafted with ethylenediamine and fish scale collagen, cross-linked with ceftazidime for wound healing application.

PubMed

Jana, Piyali; Mitra, Tapas; Selvaraj, Thirupathi Kumara Raja; Gnanamani, A; Kundu, P P

2016-11-20

Present study describes the synthesis of carboxymethyl guar gum (CMGG) from the native guar gum (GG) and the prepared CMGG is grafted with ethylenediamine (EDA) to form aminated CMGG. Then, fish scale collagen and aminated CMGG are cross-linked by ceftazidime drug through non- covalent ionic interaction. The resultant cross-linked film is subjected to the analysis of (1)HNMR, ATR-FTIR, TGA, SEM and XRD. The TNBS results revealed that 45% of interaction between EDA and CMGG and 90-95% of Ceftazidime is released from aminated CMGG-Ceftazidime-Collagen (ACCC) film after 96h of incubation at physiological pH. In vitro cell line studies reveal the biocompatibility of the cross-linked film and the antimicrobial studies display the growth inhibition against Staphylococcus aureus and Pseudomonas aeruginosa organisms. Overall, the study indicates that the incorporation of Ceftazidime into collagen and aminated CMGG can improve the functional property of aminated CMGG as well as collagen, leading to its biomedical applications. Copyright © 2016. Published by Elsevier Ltd.

Toward Understanding Amines and Their Degradation Products from Postcombustion CO2 Capture Processes with Aerosol Mass Spectrometry

PubMed Central

2015-01-01

Amine-based postcombustion CO2 capture (PCCC) is a promising technique for reducing CO2 emissions from fossil fuel burning plants. A concern of the technique, however, is the emission of amines and their degradation byproducts. To assess the environmental risk of this technique, standardized stack sampling and analytical methods are needed. Here we report on the development of an integrated approach that centers on the application of a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) for characterizing amines and PCCC-relevant species. Molecular characterization is achieved via ion chromatography (IC) and electrospray ionization high-resolution mass spectrometry (ESI-MS). The method has been optimized, particularly, by decreasing the AMS vaporizer temperature, to gain quantitative information on the elemental composition and major nitrogen-containing species in laboratory-degraded amine solvents commonly tested for PCCC applications, including ethanolamine (MEA), methyldiethanolamine (MDEA), and piperazine (PIP). The AMS-derived nitrogen-to-carbon (N/C) ratios for the degraded solvent and product mixtures agree well with the results from a total organic carbon and total nitrogen (TOC/TN) analyzer. In addition, marker ions identified in the AMS spectra are used to estimate the mass contributions of individual species. Overall, our results indicate that this new approach is suitable for characterizing PCCC-related mixtures as well as organic nitrogen species in other sample types. As an online instrument, AMS can be used for both real-time characterization of emissions from operating PCCC plants and ambient particles in the vicinity of the facilities. PMID:24617831

Adsorption of CO2 from flue gas streams by a highly efficient and stable aminosilica adsorbent.

PubMed

Liu, Shou-Heng; Lin, Yuan-Chung; Chien, Yi-Chi; Hyu, Han-Ren

2011-02-01

Three ordered mesoporous silicas (OMSs) with different pore sizes and pore architectures were prepared and modified with amine functional groups by a postgrafting method. The carbon dioxide (CO2) adsorption on these amine-modified OMSs was measured by using microbalances at 348 K, and their adsorption capacities were found to be 0.2-1.4 mmol g(-1) under ambient pressure using dry 15% CO2. It was found experimentally that the CO2 adsorption capacity and adsorption rate were attributed to the density of amine groups and pore volume, respectively. A simple method is described for the production of densely anchored amine groups on a solid adsorbent invoking direct incorporation of tetraethylenepentamine onto the as-synthesized OMSs. Unlike conventional amine-modified OMSs, which typically show CO2 adsorption capacity less than 2 mmol g(-1), such organic template occluded amine-OMS composites possessed remarkably high CO2 uptake of approximately 4.6 mmol g(-1) at 348 K and 1 atm for a dry 15% CO2/nitrogen feed mixture. The enhancement of 8% in CO2 adsorption capacity was also observed in the presence of 10.6% water vapor. Durability tests done by cyclic adsorption-desorption revealed that these adsorbents also possess excellent stability.

Formation of NDMA from ranitidine and sumatriptan: the role of pH.

PubMed

Shen, Ruqiao; Andrews, Susan A

2013-02-01

N-nitrosodimethylamine (NDMA) is an emerging disinfection by-product (DBP) which can be formed via the chloramination of amine-based precursors. The formation of NDMA is mainly determined by the speciation of chloramines and the precursor amine groups, both of which are highly dependent on pH. The impact of pH on NDMA formation has been studied for the model precursor dimethylamine (DMA) and natural organic matter (NOM), but little is known for amine-based pharmaceuticals which have been newly identified as a group of potential NDMA precursors, especially in waters impacted by treated wastewater effluents. This study investigates the role of pH in the formation of NDMA from two amine-based pharmaceuticals, ranitidine and sumatriptan, under drinking water relevant conditions. The results indicate that pH affects both the ultimate NDMA formation as well as the reaction kinetics. The maximum NDMA formation typically occurs in the pH range of 7-8. At lower pH, the reaction is limited due to the lack of non-protonated amines. At higher pH, although the initial reaction is enhanced by the increasing amount of non-protonated amines, the ultimate NDMA formation is limited because of the lack of dichloramine. Copyright © 2012 Elsevier Ltd. All rights reserved.

Thermal characterization of aminium nitrate nanoparticles.

PubMed

Salo, Kent; Westerlund, Jonathan; Andersson, Patrik U; Nielsen, Claus; D'Anna, Barbara; Hallquist, Mattias

2011-10-27

Amines are widely used and originate from both anthropogenic and natural sources. Recently, there is, in addition, a raised concern about emissions of small amines formed as degradation products of the more complex amines used in CO(2) capture and storage systems. Amines are bases and can readily contribute to aerosol mass and number concentration via acid-base reactions but are also subject to gas phase oxidation forming secondary organic aerosols. To provide more insight into the atmospheric fate of the amines, this paper addresses the volatility properties of aminium nitrates suggested to be produced in the atmosphere from acid-base reactions of amines with nitric acid. The enthalpy of vaporization has been determined for the aminium nitrates of mono-, di-, trimethylamine, ethylamine, and monoethanolamine. The enthalpy of vaporization was determined from volatility measurements of laboratory generated aerosol nanoparticles using a volatility tandem differential mobility analyzer set up. The determined enthalpy of vaporization for aminium nitrates range from 54 up to 74 kJ mol(-1), and the calculated vapor pressures at 298 K are around 10(-4) Pa. These values indicate that aminium nitrates can take part in gas-to-particle partitioning at ambient conditions and have the potential to nucleate under high NO(x) conditions, e.g., in combustion plumes.

ELUTION OF ORGANIC SOLUTES FROM DIFFERENT POLARITY SORBENTS USING SUBCRITICAL WATER. (R825394)

EPA Science Inventory

The intermolecular interactions between organic solutes and sorbent matrices under subcritical water conditions have been investigated at a pressure of 50 bar and temperatures ranging from 50 to 250°C. Both polar and nonpolar organics (chlorophenols, amines, n-alkanes...

Acid-Base Interactions of Polystyrene Sulfonic Acid in Amorphous Solid Dispersions Using a Combined UV/FTIR/XPS/ssNMR Study.

PubMed

Song, Yang; Zemlyanov, Dmitry; Chen, Xin; Nie, Haichen; Su, Ziyang; Fang, Ke; Yang, Xinghao; Smith, Daniel; Byrn, Stephen; Lubach, Joseph W

2016-02-01

This study investigates the potential drug-excipient interactions of polystyrene sulfonic acid (PSSA) and two weakly basic anticancer drugs, lapatinib (LB) and gefitinib (GB), in amorphous solid dispersions. Based on the strong acidity of the sulfonic acid functional group, PSSA was hypothesized to exhibit specific intermolecular acid-base interactions with both model basic drugs. Ultraviolet (UV) spectroscopy identified red shifts, which correlated well with the color change observed in lapatinib-PSSA solutions. Fourier transform infrared (FTIR) spectra suggest the protonation of the quinazoline nitrogen atom in both model compounds, which agrees well with data from the crystalline ditosylate salt of lapatinib. X-ray photoelectron spectroscopy (XPS) detected increases in binding energy of the basic nitrogen atoms in both lapatinib and gefitinib, strongly indicating protonation of these nitrogen atoms. (15)N solid-state NMR spectroscopy provided direct spectroscopic evidence for protonation of the quinazoline nitrogen atoms in both LB and GB, as well as the secondary amine nitrogen atom in LB and the tertiary amine nitrogen atom in GB. The observed chemical shifts in the LB-PSSA (15)N spectrum also agree very well with the lapatinib ditosylate salt where proton transfer is known. Additionally, the dissolution and physical stability behaviors of both amorphous solid dispersions were examined. PSSA was found to significantly improve the dissolution of LB and GB and effectively inhibit the crystallization of LB and GB under accelerated storage conditions due to the beneficial strong intermolecular acid-base interaction between the sulfonic acid groups and basic nitrogen centers.

Hydrogen bonded binary molecular adducts derived from exobidentate N-donor ligand with dicarboxylic acids: Acid⋯imidazole hydrogen-bonding interactions in neutral and ionic heterosynthons

NASA Astrophysics Data System (ADS)

Kathalikkattil, Amal Cherian; Damodaran, Subin; Bisht, Kamal Kumar; Suresh, Eringathodi

2011-01-01

Four new binary molecular compounds between a flexible exobidentate N-heterocycle and a series of dicarboxylic acids have been synthesized. The N-donor 1,4-bis(imidazol-1-ylmethyl)benzene (bix) was reacted with flexible and rigid dicarboxylic acids viz., cyclohexane-1,4-dicarboxylic acid (H 2chdc), naphthalene-1,4-dicarboxylic acid (H 2npdc) and 1H-pyrazole-3,5-dicarboxylic acid (H 2pzdc), generating four binary molecular complexes. X-ray crystallographic investigation of the molecular adducts revealed the primary intermolecular interactions carboxylic acid⋯amine (via O-H⋯N) as well as carboxylate⋯protonated amine (via N-H +⋯O -) within the binary compounds, generating layered and two-dimensional sheet type H-bonded networks involving secondary weak interactions (C-H⋯O) including the solvent of crystallization. Depending on the differences in p Ka values of the selected base/acid (Δp Ka), diverse H-bonded supramolecular assemblies could be premeditated. This study demonstrates the H-bonding interactions between imidazole/imidazolium cation and carboxylic acid/carboxylate anion in providing sufficient driving force for the directed assembly of binary molecular complexes. In the two-component solid form of hetero synthons involving bix and dicarboxylic acid, only H 2chdc exist as cocrystal with bix, while all the other three compounds crystallized exclusively as salt, in agreement with the Δp Ka values predicted for the formation of salts/cocrystals from the base and acid used in the synthesis of supramolecular solids.

Experimental design to optimize an Haemophilus influenzae type b conjugate vaccine made with hydrazide-derivatized tetanus toxoid.

PubMed

Laferriere, Craig; Ravenscroft, Neil; Wilson, Seanette; Combrink, Jill; Gordon, Lizelle; Petre, Jean

2011-10-01

The introduction of type b Haemophilus influenzae conjugate vaccines into routine vaccination schedules has significantly reduced the burden of this disease; however, widespread use in developing countries is constrained by vaccine costs, and there is a need for a simple and high-yielding manufacturing process. The vaccine is composed of purified capsular polysaccharide conjugated to an immunogenic carrier protein. To improve the yield and rate of the reductive amination conjugation reaction used to make this vaccine, some of the carboxyl groups of the carrier protein, tetanus toxoid, were modified to hydrazides, which are more reactive than the ε -amine of lysine. Other reaction parameters, including the ratio of the reactants, the size of the polysaccharide, the temperature and the salt concentration, were also investigated. Experimental design was used to minimize the number of experiments required to optimize all these parameters to obtain conjugate in high yield with target characteristics. It was found that increasing the reactant ratio and decreasing the size of the polysaccharide increased the polysaccharide:protein mass ratio in the product. Temperature and salt concentration did not improve this ratio. These results are consistent with a diffusion controlled rate limiting step in the conjugation reaction. Excessive modification of tetanus toxoid with hydrazide was correlated with reduced yield and lower free polysaccharide. This was attributed to a greater tendency for precipitation, possibly due to changes in the isoelectric point. Experimental design and multiple regression helped identify key parameters to control and thereby optimize this conjugation reaction.

Antagonistic Serotonergic and Octopaminergic Neural Circuits Mediate Food-Dependent Locomotory Behavior in Caenorhabditis elegans

PubMed Central

McCloskey, Richard J.; Peters, Emily

2017-01-01

Biogenic amines are conserved signaling molecules that link food cues to behavior and metabolism in a wide variety of organisms. In the nematode Caenorhabditis elegans, the biogenic amines serotonin (5-HT) and octopamine regulate a number of food-related behaviors. Using a novel method for long-term quantitative behavioral imaging, we show that 5-HT and octopamine jointly influence locomotor activity and quiescence in feeding and fasting hermaphrodites, and we define the neural circuits through which this modulation occurs. We show that 5-HT produced by the ADF neurons acts via the SER-5 receptor in muscles and neurons to suppress quiescent behavior and promote roaming in fasting worms, whereas 5-HT produced by the NSM neurons acts on the MOD-1 receptor in AIY neurons to promote low-amplitude locomotor behavior characteristic of well fed animals. Octopamine, produced by the RIC neurons, acts via SER-3 and SER-6 receptors in SIA neurons to promote roaming behaviors characteristic of fasting animals. We find that 5-HT signaling is required for animals to assume food-appropriate behavior, whereas octopamine signaling is required for animals to assume fasting-appropriate behavior. The requirement for both neurotransmitters in both the feeding and fasting states enables increased behavioral adaptability. Our results define the molecular and neural pathways through which parallel biogenic amine signaling tunes behavior appropriately to nutrient conditions. SIGNIFICANCE STATEMENT Animals adjust behavior in response to environmental changes, such as fluctuations in food abundance, to maximize survival and reproduction. Biogenic amines, such as like serotonin, are conserved neurotransmitters that regulate behavior and metabolism in relation to energy status. Disruptions of biogenic amine signaling contribute to human neurological diseases of mood, appetite, and movement. In this study, we investigated the roles of the biogenic amines serotonin and octopamine in regulating locomotion behaviors associated with feeding and fasting in the roundworm Caenorhabditis elegans. We identified neural circuits through which these signals work to govern behavior. Understanding the molecular pathways through which biogenic amines function in model organisms may improve our understanding of dysfunctions of appetite and behavior found in mammals, including humans. PMID:28698386

Carbon nanotube-supported Au-Pd alloy with cooperative effect of metal nanoparticles and organic ketone/quinone groups as a highly efficient catalyst for aerobic oxidation of amines.

PubMed

Deng, Weiping; Chen, Jiashu; Kang, Jincan; Zhang, Qinghong; Wang, Ye

2016-05-21

Functionalised carbon nanotube (CNT)-supported Au-Pd alloy nanoparticles were highly efficient catalysts for the aerobic oxidation of amines. We achieved the highest turnover frequencies (>1000 h(-1)) for the oxidative homocoupling of benzylamine and the oxidative dehydrogenation of dibenzylamine. We discovered a cooperative effect between Au-Pd nanoparticles and ketone/quinone groups on CNTs.

An evaluation of corrosion protection by two epoxy primers on 2219-T87 and 7075-T73 aluminum

NASA Technical Reports Server (NTRS)

Mendrek, M. J.

1992-01-01

A comparison of the corrosion protection provided by two amine epoxy primers was made using salt fog, alternate immersion, and total immersion as exposure media. The study is the result of a request to use an unqualified low volatile organic carbon (VOC) primer (AKZO 463-6-78) in place of the current primer (AKZO 463-6-3) because environmental regulations have eliminated use of the current primer in many states. Primed, scribed samples of 2219-T87 and 7075-T73 aluminum were exposed to 5-percent NaCl salt fog and 3.5-percent NaCl alternate immersion for a period of 90 days. In addition, electrode samples immersed in 3.5-percent NaCl were tested using electrochemical impedance spectroscopy (EIS). The EG&G model 368 ac impedance measurement system was used to monitor changing properties of AKZO 463-6-78 and AKZO 463-6-3 primed 2219-T87 aluminum for a period of 30 days. The response of the corroding system of a frequency scan can be modeled in terms of an equivalent circuit consisting of resistors and capacitors in a specific arrangement. Each resistor/capacitor combination represents physical processes taking place within the electrolyte, at the electrolyte/primer surface, within the coating, and at the coating/substrate surface. Values for the resistors and capacitors are assigned following a nonlinear least squares fit of the data to the equivalent circuit. Changes in the values of equivalent circuit parameters during the 30-day exposure allow assessment of the time to and mechanism of coating breakdown.

How salt lakes affect atmospheric new particle formation: A case study in Western Australia.

PubMed

Kamilli, K A; Ofner, J; Krause, T; Sattler, T; Schmitt-Kopplin, P; Eitenberger, E; Friedbacher, G; Lendl, B; Lohninger, H; Schöler, H F; Held, A

2016-12-15

New particle formation was studied above salt lakes in-situ using a mobile aerosol chamber set up above the salt crust and organic-enriched layers of seven different salt lakes in Western Australia. This unique setup made it possible to explore the influence of salt lake emissions on atmospheric new particle formation, and to identify interactions of aqueous-phase and gas-phase chemistry. New particle formation was typically observed at enhanced air temperatures and enhanced solar irradiance. Volatile organic compounds were released from the salt lake surfaces, probably from a soil layer enriched in organic compounds from decomposed leaf litter, and accumulated in the chamber air. After oxidation of these organic precursor gases, the reaction products contributed to new particle formation with observed growth rates from 2.7 to 25.4nmh -1 . The presence of ferrous and ferric iron and a drop of pH values in the salt lake water just before new particle formation events indicated that organic compounds were also oxidized in the aqueous phase, affecting the new particle formation process in the atmosphere. The contribution of aqueous-phase chemistry to new particle formation is assumed, as a mixture of hundreds of oxidized organic compounds was characterized with several analytical techniques. This chemically diverse composition of the organic aerosol fraction contained sulfur- and nitrogen-containing organic compounds, and halogenated organic compounds. Coarse mode particles were analyzed using electron microscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy. Ultra-high resolution mass spectrometry was applied to analyze filter samples. A targeted mass spectral analysis revealed the formation of organosulfates from monoterpene precursors and two known tracers for secondary organic aerosol formation from atmospheric oxidation of 1,8-cineole, which indicates that a complex interplay of aqueous-phase and gas-phase oxidation of monoterpenes contributes to new particle formation in the investigated salt lake environment. Copyright © 2016. Published by Elsevier B.V.

Managing Your Wine Fermentation to Reduce the Risk of Biogenic Amine Formation

PubMed Central

Smit, Anita Yolandi; Engelbrecht, Lynn; du Toit, Maret

2012-01-01

Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the inoculated starter cultures for alcoholic and malolactic fermentation (MLF). MLF can be conducted using co-inoculation or an inoculation after the completion of alcoholic fermentation that may also affect the level of biogenic amines in wine. This study focused on the impact of the addition of complex commercial yeast and bacterial nutrients and the use of different MLF inoculation scenarios on the production of biogenic amines in wine. Results showed that the addition of complex nutrients to real grape must could potentially increase histamine concentrations in wine. The same experiment in synthetic grape must showed a similar trend for putrescine and cadaverine. The effect of different MLF inoculation scenarios was examined in two cultivars, Pinotage and Shiraz. Conflicting results was obtained. In the Shiraz, co-inoculation resulted in lower biogenic amine concentrations after MLF compared to before MLF, while the concentration was higher in the Pinotage. However, the production of biogenic amines was affected more by the presence of decarboxylase positive lactic acid bacteria than by the addition of complex nutrients or the inoculation scenario. PMID:22419915

Unexpected role of activated carbon in promoting transformation of secondary amines to N-nitrosamines.

PubMed

Padhye, Lokesh; Wang, Pei; Karanfil, Tanju; Huang, Ching-Hua

2010-06-01

Activated carbon (AC) is the most common solid phase extraction material used for analysis of nitrosamines in water. It is also widely used for the removal of organics in water treatment and as a catalyst or catalyst support in some industrial applications. In this study, it was discovered that AC materials can catalyze transformation of secondary amines to yield trace levels of N-nitrosamines under ambient aerobic conditions. All 11 commercial ACs tested in the study formed nitrosamines from secondary amines. Among the different ACs, the N-nitrosodimethylamine (NDMA) yield at pH 7.5 ranged from 0.001% to 0.01% of initial amount of aqueous dimethylamine (DMA) concentration, but at 0.05-0.29% of the amount of adsorbed DMA by AC. Nitrosamine yield increased with higher pH and for higher molecular weight secondary amines, probably because of increased adsorption of amines. Presence of oxygen was a critical factor in the transformation of secondary amines, since ACs with adsorbed secondary amines dried under air for longer period of time exhibited significantly higher nitrosamine yields. The AC-catalyzed nitrosamine formation was also observed in surface water and wastewater effluent samples. Properties of AC play an important role in the nitrosamine yields. Preliminary evaluation indicated that nitrosamine formation was higher on reduced than oxidized AC surfaces. Overall, the study results show that selecting ACs and reaction conditions are important to minimize analytical errors and undesirable formation associated with nitrosamines in water samples.

Distribution of Aliphatic Amines in CO, CV, and CK Carbonaceous Chondrites and Relation to Mineralogy and Processing History

NASA Technical Reports Server (NTRS)

Aponte, Jose C.; Abreu, Neyda M.; Glavin, Daniel P.; Dworkin, Jason P.; Elsila, Jamie E.

2017-01-01

The analysis of water-soluble organic compounds in meteorites provides valuable insights into the prebiotic synthesis of organic matter and the processes that occurred during the formation of the solar system. We investigated the concentration of aliphatic monoamines present in hot acid water extracts of the unaltered Antarctic carbonaceous chondrites, Dominion Range (DOM) 08006 (CO3) and Miller Range (MIL) 05013 (CO3), and the thermally altered meteorites, Allende (CV3), LAP 02206 (CV3), GRA 06101 (CV3), Allan Hills (ALH) 85002 (CK4), and EET 92002 (CK5). We have also reviewed and assessed the petrologic characteristics of the meteorites studied here to evaluate the effects of asteroidal processing on the abundance and molecular distributions of monoamines. The CO3, CV3, CK4, and CK5 meteorites studied here contain total concentrations of amines ranging from 1.2 to 4.0 nmol/g of meteorite; these amounts are 1-3 orders of magnitude below those observed in carbonaceous chondrites from the CI, CM, and CR groups. The low-amine abundances for CV and CK chondrites may be related to their extensive degree of thermal metamorphism and/or to their low original amine content. Although the CO3 meteorites, DOM 08006 and MIL 05013, do not show signs of thermal and aqueous alteration, their monoamine contents are comparable to those observed in moderately/extensively thermally altered CV3, CK4, and CK5 carbonaceous chondrites. The low content of monoamines in pristine CO carbonaceous chondrites suggests that the initial amounts, and not asteroidal processes, play a dominant role in the content of monoamines in carbonaceous chondrites. The primary monoamines, methylamine, ethylamine, and n-propylamine constitute the most abundant amines in the CO3, CV3, CK4, and CK5 meteorites studied here. Contrary to the predominance of n-x-amino acid isomers in CO3 and thermally altered meteorites, there appears to be no preference for the larger n-amines.

Assessing the Origins of Aliphatic Amines in the Murchison Meteorite from their Compound-Specific Carbon Isotopic Ratios and Enantiomeric Composition

NASA Technical Reports Server (NTRS)

Aponte, Jose; Dworkin, Jason; Elsila, Jamie E.

2014-01-01

The study of meteoritic organic compounds provides a unique window into the chemical inventory of the early Solar System and prebiotic chemistry that may have been important for the origin of life on Earth. Multiple families of organic compounds have been extracted from the Murchison meteorite, which is one of the most thoroughly studied carbonaceous chondrites. The amino acids extracted from Murchison have been extensively analyzed, including measurements of non-terrestrial stable isotopic ratios and discoveries of L-enantiomeric excesses for alpha-dialkyl amino acids, notably isovaline. However, although the isotopic signatures of bulk amine-containing fractions have been measured, the isotopic ratios and enantiomeric composition of individual aliphatic amines, compounds that are chemically related to amino acids, remain unknown. Here, we report a novel method for the extraction, separation, identification and quantitation of aliphatic monoamines extracted from the Murchison meteorite. Our results show a complete suite of structural isomers, with a larger concentration of methylamine and ethylamine and decreasing amine concentrations with increasing carbon number. The carbon isotopic compositions of fourteen meteoritic aliphatic monoamines were measured, with delta C-13 values ranging from +21% to +129%, showing a decrease in C-13 with increasing carbon number, a relationship that may be consistent with the chain elongation mechanism under kinetic control previously proposed for meteoritic amino acids. We also found the enantiomeric composition of sec-butylamine, a structural analog to isovaline, was racemic within error, while the isovaline extracted from the same Murchison piece showed an L-enantiomeric excess of 9.7; this result suggested that processes leading to enantiomeric excess in the amino acid did not affect the amine. We used these collective data to assess the primordial synthetic origins of these meteoritic aliphatic amines and their potential linkage to meteoritic amino acids.

Organic Lecture Demonstrations.

ERIC Educational Resources Information Center

Silversmith, Ernest F.

1988-01-01

Provides a listing of 35 demonstrations designed to generate interest in organic chemistry and help put points across. Topics include opening lecture; molecular structure and properties; halogenation; nucleophilic substitution, alkenes and dienes, stereochemistry, spectroscopy, alcohols and phenols, aldehydes and ketones; carboxylic acids, amines,…

Liquid precursor inks for deposition of In--Se, Ga--Se and In--Ga--Se

DOEpatents

Curtis, Calvin J.; Hersh, Peter A.; Miedaner, Alexander; Habas, Susan; van Hest, Maikel; Ginley, David S.

2015-08-11

An ink includes a solution of selenium in ethylene diamine solvent and a solution of at least one metal salt selected from the group consisting of an indium salt or a gallium salt in at least one solvent including an organic amide. The organic amide can include dimethylformamide. The organic amide can include N-methylpyrrolidone.

Crystallization of a salt of a weak organic acid and base: solubility relations, supersaturation control and polymorphic behavior.

PubMed

Jones, H P; Davey, R J; Cox, B G

2005-03-24

Control of crystallization processes for organic salts is of importance to the pharmaceutical industry as many active pharmaceutical materials are marketed as salts. In this study, a method for estimating the solubility product of a salt of a weak acid and weak base from measured pH-solubility data is described for the first time. This allows calculation of the supersaturation of solutions at known pH. Ethylenediammonium 3,5-dinitrobenzoate is a polymorphic organic salt. A detailed study of the effects of pH, supersaturation, and temperature of crystallization on the physical properties of this salt shows that the desired polymorph may be produced by appropriate selection of the pH and supersaturation of crystallization. Crystal morphology is also controlled by these crystallization conditions.

Additives for High Temperature Hydraulic Fluids.

DTIC Science & Technology

HYDRAULIC FLUIDS, ADDITIVES, TRIAZINES, FERROCENES , PHOSPHINE , SULFOXIDES, SYNTHESIS(CHEMISTRY), SCIENTIFIC RESEARCH, FLUORINE COMPOUNDS, PHOSPHINE OXIDES, ORGANIC PHOSPHORUS COMPOUNDS, AMINES, HEAT RESISTANT MATERIALS.

Phosphotungstic acid encapsulated in the mesocages of amine-functionalized metal-organic frameworks for catalytic oxidative desulfurization.

PubMed

Wang, Xu-Sheng; Huang, Yuan-Biao; Lin, Zu-Jin; Cao, Rong

2014-08-21

Highly dispersed Keggin-type phosphotungstic acid (H3PW12O40, PTA) encapsulated in the mesocages of amine-functionalized metal-organic frameworks MIL-101(Cr)-NH2 has been prepared by an anion-exchange method. PTA anions (PW12O40(3-)) are stabilized in the mesocages via the electrostatic interaction with amino groups of the MIL-101(Cr)-NH2. The obtained catalyst (denoted PTA@MIL-101(Cr)-NH2) exhibits high catalytic activity in the extractive and catalytic oxidative desulfurization (ECODS) system under mild conditions. Moreover, it can be easily recovered and recycled several times without leaching and loss of activity.

Selective and sensitive aqueous-phase detection of 2,4,6-trinitrophenol (TNP) by an amine-functionalized metal-organic framework.

PubMed

Joarder, Biplab; Desai, Aamod V; Samanta, Partha; Mukherjee, Soumya; Ghosh, Sujit K

2015-01-12

Highly selective and sensitive aqueous-phase detection of nitro explosive 2,4,6-trinitrophenol (TNP) by a hydrolytically stable 3D luminescent metal-organic framework is reported. The compound senses TNP exclusively even in the presence of other nitro-compounds, with an unprecedented sensitivity in the MOF regime by means of strategic deployment of its free amine groups. Such an accurate sensing of TNP, widely recognized as a harmful environmental contaminant in water media, establishes this new strategic approach as one of the frontiers to tackle present-day security and health concerns in a real-time scenario. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Intercalation of the layered solid acid HCa/sub 2/Nb/sub 3/O/sub 10/ by organic amines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobson, A.J.; Johnson, J.W.; Lewandowski, J.T.

1987-01-01

Layered compounds of formula C/sub n/H/sub 2n+1/NH/sub 3/Ca/sub 2/Nb/sub 3/O/sub 10/ are formed by reaction of n-alkylamines with the solid acid HCa/sub 2/Nb/sub 3/O/sub 10/. Other organic bases such as pyridine can also be intercalated. The lattice constants of the new compounds have been determined by powder X-ray diffraction. The unit cells are tetragonal with a axes that are unchanged with variation of the intercalated amine. The c axes lengths (layer spacings) vary systematically with the hydrocarbon chain length of the alkylamine.

Preparation and characterization of plasticized palm-based polyurethane solid polymer electrolyte

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daud, Farah Nadia; Ahmad, Azizan; Badri, Khairiah Haji

2013-11-27

Palm-based polyurethane solid polymer electrolyte was prepared via prepolymerization method between palm kernel oil based polyols (PKO-p) and 2,4’-diphenylmethane diisocyanate (2,4’-MDI) in acetone at room temperature with the vary amount of lithium trifuoromethanesulfonate (LiCF{sub 3}SO{sub 3}) salt and polyethylene glycol (PEG). The film was analyzed using attenuated total reflection infrared (ATR-IR) spectroscopy, electrochemical impedance spectroscopy (EIS) and X-ray diffractometry (XRD). EIS result indicated ionic conductivity obtained with 30 wt% LiCF3SO3 increased to 6.55 × 10{sup −6} S cm{sup −1} when 10 wt.% of plasticizer was added into the system. FTIR analysis showed the interaction between lithium ions and amine (-N-H)more » at 3600–3100 cm{sup −1}, carbonyl (-C=O) at 1750–1650 cm{sup −1} and ether (-C-O-C-) at 1150–1000 cm{sup −1} of the polyurethane forming polymer-salt complexes. The XRD result confirmed that LiCF{sub 3}SO{sub 3} salt completely dissociated within the polyurethane film with the absence of crystalline peaks of LiCF{sub 3}SO{sub 3}.« less

Excitation-emission spectra and fluorescence quantum yields for fresh and aged biogenic secondary organic aerosols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Hyun Ji; Laskin, Alexander; Laskin, Julia

2013-05-10

Certain biogenic secondary organic aerosols (SOA) become absorbent and fluorescent when exposed to reduced nitrogen compounds such as ammonia, amines and their salts. Fluorescent SOA may potentially be mistaken for biological particles by detection methods relying on fluorescence. This work quantifies the spectral distribution and effective quantum yields of fluorescence of SOA generated from two monoterpenes, limonene and a-pinene, and two different oxidants, ozone (O3) and hydroxyl radical (OH). The SOA was generated in a smog chamber, collected on substrates, and aged by exposure to ~100 ppb ammonia vapor in air saturated with water vapor. Absorption and excitation-emission matrix (EEM)more » spectra of aqueous extracts of aged and control SOA samples were measured, and the effective absorption coefficients and fluorescence quantum yields (~0.005 for 349 nm excitation) were determined from the data. The strongest fluorescence for the limonene-derived SOA was observed for excitation = 420+- 50 nm and emission = 475 +- 38 nm. The window of the strongest fluorescence shifted to excitation = 320 +- 25 nm and emission = 425 +- 38 nm for the a-pinene-derived SOA. Both regions overlap with the excitation-emission matrix (EEM) spectra of some of the fluorophores found in primary biological aerosols. Our study suggests that, despite the low quantum yield, the aged SOA particles should have sufficient fluorescence intensities to interfere with the fluorescence detection of common bioaerosols.« less

Excitation-emission spectra and fluorescence quantum yields for fresh and aged biogenic secondary organic aerosols.

PubMed

Lee, Hyun Ji Julie; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey A

2013-06-04

Certain biogenic secondary organic aerosols (SOA) become absorbent and fluorescent when exposed to reduced nitrogen compounds such as ammonia, amines, and their salts. Fluorescent SOA may potentially be mistaken for biological particles by detection methods relying on fluorescence. This work quantifies the spectral distribution and effective quantum yields of fluorescence of water-soluble SOA generated from two monoterpenes, limonene and α-pinene, and two different oxidants, ozone (O3) and hydroxyl radical (OH). The SOA was generated in a smog chamber, collected on substrates, and aged by exposure to ∼100 ppb ammonia in air saturated with water vapor. Absorption and excitation-emission matrix (EEM) spectra of aqueous extracts of aged and control SOA samples were measured, and the effective absorption coefficients and fluorescence quantum yields (∼0.005 for 349 nm excitation) were determined from the data. The strongest fluorescence for the limonene-derived SOA was observed for λexcitation = 420 ± 50 nm and λemission = 475 ± 38 nm. The window of the strongest fluorescence shifted to λexcitation = 320 ± 25 nm and λemission = 425 ± 38 nm for the α-pinene-derived SOA. Both regions overlap with the EEM spectra of some of the fluorophores found in primary biological aerosols. Despite the low quantum yield, the aged SOA particles may have sufficient fluorescence intensities to interfere with the fluorescence detection of common bioaerosols.

Probing into hybrid organic-molecule and InAs quantum-dots nanosystem with multistacked dots-in-a-well units

NASA Astrophysics Data System (ADS)

Chen, Miaoxiang; Kobashi, Kazufumi

2012-09-01

Hybridizing air-stable organic-molecules with advanced III-V semiconductor quantum-dots (QDs) structures can be utilized to create a new generation of biochemical sensing devices. In order to enhance their optical performances, the active regions in these QDs structures commonly consist of multistacked dots-in-a-well (DWELL) units. The effects of grafted molecules on the performances of the QDs structures with multistacked DWELLs, however, still remain unclear. Here, we show the significant improvements in the optical properties of InAs QDs in a hybrid nanosystem obtained by grafting biocompatible diazonium salt compound (amine donor) atop InAs QDs structure. Since its interface between the QDs structure and molecular monolayer retains an uncontaminated and non-oxidized condition, the nanosystem is an ideal platform to study the intrinsic properties of charge-carrier transport inside the system. Because of the complexity of the energy-levels in the QDs structure due to the existing surface QDs and DWELLs, selective excitation wavelengths (400, 633, and 885 nm, respectively) with different photo-energies are used to exactly analyze the complete charging mechanism in these QDs. A clear view of charge-carrier transfer inside the nanosystem is revealed by employing photoluminescence technique under selective-wavelength excitations. The present work provides new quantitative evidences for exploiting inorganic QDs applications in complex biological systems.

Naturally occurring alkaline amino acids function as efficient catalysts on Knoevenagel condensation at physiological pH: a mechanistic elucidation.

PubMed

Li, Weina; Fedosov, Sergey; Tan, Tianwei; Xu, Xuebing; Guo, Zheng

2014-05-01

To maintain biological functions, thousands of different reactions take place in human body at physiological pH (7.0) and mild conditions, which is associated with health and disease. Therefore, to examine the catalytic function of the intrinsically occurring molecules, such as amino acids at neutral pH, is of fundamental interests. Natural basic α-amino acid of L-lysine, L-arginine, and L-histidine neutralized to physiological pH as salts were investigated for their ability to catalyze Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate. Compared with their free base forms, although neutralized alkaline amino acid salts reduced the catalytic activity markedly, they were still capable to perform an efficient catalysis at physiological pH as porcine pancreatic lipase (PPL), one of the best enzymes that catalyze Knoevenagel condensation. In agreement with the fact that the three basic amino acids were well neutralized, stronger basic amino acid Arg and Lys showed more obvious variation in NH bend peak from the FTIR spectroscopy study. Study of ethanol/water system and quantitative kinetic analysis suggested that the microenvironment in the vicinity of amino acid salts and protonability/deprotonability of the amine moiety may determine their catalytic activity and mechanism. The kinetic study of best approximation suggested that the random binding might be the most probable catalytic mechanism for the neutralized alkaline amino acid salt-catalyzed Knoevenagel condensation.

Organic Electrochemistry in Aluminum Chloride Melts.

DTIC Science & Technology

1976-08-15

establishing a new, room temperature molten salt system. The low temperature fused salt was prepared by combining aluminum...narrow (600 mY) potential range. Organic electrosynthesis was conducted in a 50-50 by volume molten salt - benzene solution. This mixed solvent...room temperature molten salt system, namely a 67:33 mole percent aluminum chloride: ethylpyridinium bromide melt and in a 50-50 by volume solution of the

The ozonolysis of primary aliphatic amines in single and multicomponent fine particles

NASA Astrophysics Data System (ADS)

Zahardis, J.; Geddes, S.; Petrucci, G. A.

2007-10-01

The oxidative processing by ozone of the particulate amines octadecylamine (ODA) and hexadecylamine (HDA) is reported. Ozonolysis of these amines resulted in strong NO2- and NO3- ion signals that increased with ozone exposure as monitored by photoelectron resonance capture ionization aerosol mass spectrometry. These products suggest a mechanism of progressive oxidation of the particulate amines to nitro alkanes. Additionally, a strong ion signal at 125 m/z is assigned to the ion NO3-(HNO3). For ozonized mixed particles containing ODA or HDA + oleic acid (OL), with pO3≥3×10^{-7 atm, imine, secondary amide, and tertiary amide products were measured. These products most likely arise from reactions of amines with aldehydes (for imines) and stabilized Criegee intermediates (SCI) or secondary ozonides (for amides) from the fatty acid. The routes to amides via SCI and/or secondary ozonides was shown to be more important than comparable amide forming reactions between amines and organic acids, using azelaic acid as a test compound. Finally, direct evidence is provided for the formation of a surface barrier in the ODA + OL reaction system that resulted in the retention of OL at high ozone exposures (up to 10-3 atm for 17 s). This effect was not observed in HDA + OL or single component OL particles, suggesting that it may be a species-specific surfactant effect from an in situ generated amide or imine. Implications to tropospheric chemistry, including particle bound amines as sources of oxidized gas phase nitrogen species (e.g. NO2, NO3), formation of nitrogen enriched HULIS via ozonolysis of amines and source apportionment are discussed.}

The ozonolysis of primary aliphatic amines in fine particles

NASA Astrophysics Data System (ADS)

Zahardis, J.; Geddes, S.; Petrucci, G. A.

2008-02-01

The oxidative processing by ozone of the particulate amines octadecylamine (ODA) and hexadecylamine (HDA) is reported. Ozonolysis of these amines resulted in strong NO2- and NO3- ion signals that increased with ozone exposure as monitored by photoelectron resonance capture ionization aerosol mass spectrometry. These products suggest a mechanism of progressive oxidation of the particulate amines to nitroalkanes. Additionally, a strong ion signal at 125 m/z is assigned to the ion NO3- (HNO3). For ozonized mixed particles containing ODA or HDA + oleic acid (OL), with pO3≥3×10-7 atm, imine, secondary amide, and tertiary amide products were measured. These products most likely arise from reactions of amines with aldehydes (for imines) and stabilized Criegee intermediates (SCI) or secondary ozonides (for amides) from the fatty acid. The routes to amides via SCI and/or secondary ozonides were shown to be more important than comparable amide forming reactions between amines and organic acids, using azelaic acid as a test compound. Finally, direct evidence is provided for the formation of a surface barrier in the ODA + OL reaction system that resulted in the retention of OL at high ozone exposures (up to 10-3 atm for 17 s). This effect was not observed in HDA + OL or single component OL particles, suggesting that it may be a species-specific surfactant effect from an in situ generated amide or imine. Implications to tropospheric chemistry, including particle bound amines as sources of oxidized gas phase nitrogen species (e.g.~NO2, NO3), formation of nitrogen enriched HULIS via ozonolysis of amines and source apportionment are discussed.

Detection of cometary amines in samples returned by Stardust

NASA Astrophysics Data System (ADS)

Glavin, D. P.; Dworkin, J. P.; Sandford, S. A.

2008-02-01

The abundances of amino acids and amines, as well as their enantiomeric compositions, were measured in samples of Stardust comet-exposed aerogel and foil using liquid chromatography with UV fluorescence detection and time of flight mass spectrometry (LC-FD/ToF-MS). A suite of amino acids and amines including glycine, L-alanine, β-alanine (BALA), γ-amino-n-butyric acid (GABA), ɛ-amino-n-caproic acid (EACA), ethanolamine (MEA), methylamine (MA), and ethylamine (EA) were identified in acid-hydrolyzed, hot-water extracts of these Stardust materials above background levels. With the exception of MA and EA, all other primary amines detected in cometexposed aerogel fragments C2054,4 and C2086,1 were also present in the flight aerogel witness tile that was not exposed to the comet, indicating that most amines are terrestrial in origin. The enhanced relative abundances of MA and EA in comet-exposed aerogel compared to controls, coupled with MA to EA ratios (C2054,4: 1.0 ± 0.2; C2086,1: 1.8 ± 0.2) that are distinct from preflight aerogels (E243-13C and E243-13F: 7 ± 3), suggest that these volatile amines were captured from comet Wild 2. MA and EA were present predominantly in an acid-hydrolyzable bound form in the aerogel, rather than as free primary amines, which is consistent with laboratory analyses of cometary ice analog materials. It is possible that Wild 2 MA and EA were formed on energetically processed icy grains containing ammonia and approximately equal abundances of methane and ethane. The presence of cometary amines in Stardust material supports the hypothesis that comets were an important source of prebiotic organic carbon and nitrogen on the early Earth.

Rice choline monooxygenase (OsCMO) protein functions in enhancing glycine betaine biosynthesis in transgenic tobacco but does not accumulate in rice (Oryza sativa L. ssp. japonica).

PubMed

Luo, Di; Niu, Xiangli; Yu, Jinde; Yan, Jun; Gou, Xiaojun; Lu, Bao-Rong; Liu, Yongsheng

2012-09-01

Glycine betaine (GB) is a compatible quaternary amine that enables plants to tolerate abiotic stresses, including salt, drought and cold. In plants, GB is synthesized through two-step of successive oxidations from choline, catalyzed by choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH), respectively. Rice is considered as a typical non-GB accumulating species, although the entire genome sequencing revealed rice contains orthologs of both CMO and BADH. Several studies unraveled that rice has a functional BADH gene, but whether rice CMO gene (OsCMO) is functional or a pseudogene remains to be elucidated. In the present study, we report the functional characterization of rice CMO gene. The OsCMO gene was isolated from rice cv. Nipponbare (Oryza sativa L. ssp. japonica) using RT-PCR. Northern blot demonstrated the transcription of OsCMO is enhanced by salt stress. Transgenic tobacco plants overexpressing OsCMO results in increased GB content and elevated tolerance to salt stress. Immunoblotting analysis demonstrates that a functional OsCMO protein with correct size was present in transgenic tobacco but rarely accumulated in wild-type rice plants. Surprisingly, a large amount of truncated proteins derived from OsCMO was induced in the rice seedlings in response to salt stresses. This suggests that it is the lack of a functional OsCMO protein that presumably results in non-GB accumulation in the tested rice plant. Expression and transgenic studies demonstrate OsCMO is transcriptionally induced in response to salt stress and functions in increasing glycinebetaine accumulation and enhancing tolerance to salt stress. Immunoblotting analysis suggests that no accumulation of glycinebetaine in the Japonica rice plant presumably results from lack of a functional OsCMO protein.

Amine-pillared Nanosheet Adsorbents for CO2 Capture Applications

NASA Astrophysics Data System (ADS)

Jiang, Hui

Amine-functionalized solid adsorbents have gained attention within the last decade for their application in carbon dioxide capture, due to their many advantages such as low energy cost for regeneration, tunable structure, elimination of corrosion problems, and additional advantages. However, one of the challenges facing this technology is to accomplish both high CO 2 capture capacity along with high CO2 diffusion rates concurrently. Current amine-based solid sorbents such as porous materials similar to SBA-15 have large pores diffusion entering molecules; however, the pores become clogged upon amine inclusion. To meet this challenge, our group's solution involves the creation of a new type of material which we are calling-amino-pillared nanosheet (APN) adsorbents which are generated from layered nanosheet precursors. These materials are being proposed because of their unique lamellar structure which exhibits ability to be modified by organic or inorganic pillars through consecutive swelling and pillaring steps to form large mesoporous interlayer spaces. After the expansion of the layer space through swelling and pillaring, the large pore space can be functionalized with amine groups. This selective functionalization is possible by the choice of amine group introduced. Our choice, large amine molecules, do not access the micropore within each layer; however, either physically or chemically immobilized onto the surface of the mesoporous interlayer space between each layer. The final goal of the research is to investigate the ability to prepare APN adsorbents from a model nanoporous layered materials including nanosheets precursor material MCM-22(P) and nanoporous layered silicate material AMH-3. MCM-22(P) contains 2-dimensional porous channels, 6 membered rings (MB) openings perpendicular to the layers and 10 MB channels in the plane of the layers. However, the transport limiting openings (6 MB) to the layers is smaller than CO2 gas molecules. In contrast, AMH-3 has 3D microporous layers with 8 MB openings in the plane of the layers, as well as perpendicular to the layers, which are larger than CO2 molecules. Based on the structure differences between nanosheets precursor material MCM-22(P) and nanoporous layered silicate material AMH-3, the latter might be more suitable for CO 2 capturer application as an APN candidate material. However, none of the assumptions above have been approved experimentally. In this study, the influence of the amine loading on adsorption capacity and kinetics of adsorption for the mixed porosity material pillared MCM-22 (P) (also called MCM-36) is studied systematically, in order to determine a potential route to achieve a final material with both high amine loading and high adsorption capacity. We first synthesized MCM-22(P), followed by swelling and pillaring to create MCM-36. Polymeric amines such as polyethylenimine (PEI) are used as an organic component of the supported amine adsorbents, with varying polymer loadings within the adsorbents used. The kinetics and diffusion properties of carbon dioxide capture on a MCM-36 pillared material impregnated with amine containing Polyethylenimine polymers has been investigated. It was determined that the introduction of amine polymer cannot be used to improve the capture capacity of the support over that of the bare material, due to the fact that with the addition of a high loading of amine polymer the large pore diffusion channels become impossible for carbon dioxide molecules to diffuse through. This sets an upper limit to the capture capacity of polymer impregnated MCM-36 for carbon dioxide which does not surpass that for the initial bare material, and greatly reduces the utility of using this sort of amine-solid adsorbent for carbon capture plans in the future.

Compound-Specific Isotope Analysis of Amino Acids for Stardust-Returned Samples

NASA Technical Reports Server (NTRS)

Cook, Jamie; Elsila, Jamie E.; Stern J. C.; Glavin, D. P.; Dworkin, J. P.

2008-01-01

Significant portions of the early Earth's prebiotic organic inventory , including amino acids, could have been delivered to the Earth's sur face by comets and their fragments. Analysis of comets via spectrosc opic observations has identified many organic molecules, including me thane, ethane, arnmonia, cyanic acid, formaldehyde, formamide, acetal ehyde, acetonitrile, and methanol. Reactions between these identifie d molecules could allow the formation of more complex organics such a s amino acids. Isotopic analysis could reveal whether an extraterrest rial signature is present in the Stardust-exposed amines and amino ac ids. Although bulk isotopic analysis would be dominated by the EACA contaminant's terrestrial signature, compoundspecific isotope analysi s (CSIA) could determine the signature of each of the other individua l amines. Here, we report on progress made towards CSIA of the amino acids glycine and EACA in Stardustreturned samples.

Method for separating mono- and di-octylphenyl phosphoric acid esters

DOEpatents

Arnold, Jr., Wesley D.

1977-01-01

A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters.

Integrating metabolomics and transcriptomics data to discover a biocatalyst that can generate the amine precursors for alkamide biosynthesis

PubMed Central

Rizhsky, Ludmila; Jin, Huanan; Shepard, Michael R.; Scott, Harry W.; Teitgen, Alicen M.; Perera, M. Ann; Mhaske, Vandana; Jose, Adarsh; Zheng, Xiaobin; Crispin, Matt; Wurtele, Eve S.; Jones, Dallas; Hur, Manhoi; Góngora-Castillo, Elsa; Buell, C. Robin; Minto, Robert E.; Nikolau, Basil J.

2016-01-01

Summary The Echinacea genus is exemplary of over 30 plant families that produce a set of bioactive amides, called alkamides. The Echinacea alkamides may be assembled from two distinct moieties, a branched-chain amine that is acylated with a novel polyunsaturated fatty acid. In this study we identified the potential enzymological source of the amine moiety as a pyridoxal phosphate dependent decarboxylating enzyme that uses branched chain amino acids as substrate. This identification was based on a correlative analysis of the transcriptomes and metabolomes of 36 different E. purpurea tissues and organs, which expressed distinct alkamide profiles. Although no correlation was found between the accumulation patterns of the alkamides and their putative metabolic precursors (i.e., fatty acids and branched chain amino acids), isotope-labeling analyses supported the transformation of valine and isoleucine to isobutylamine and 2-methylbutylamine as reactions of alkamide biosynthesis. Sequence homology identified the pyridoxal phosphate dependent decarboxylase-like proteins in the translated proteome of E. purpurea. These sequences were prioritized for direct characterization by correlating their transcript levels with alkamide accumulation patterns in different organs and tissues, and this multi-pronged approach led to the identification and characterization of a branched-chain amino acid decarboxylase, which would appear to be responsible for generating the amine moieties of naturally occurring alkamides. PMID:27497272

CO 2 induced phase transitions in diamine-appended metal–organic frameworks

DOE PAGES

Vlaisavljevich, Bess; Odoh, Samuel O.; Schnell, Sondre K.; ...

2015-06-17

Using a combination of density functional theory and lattice models, we study the effect of CO 2 adsorption in an amine functionalized metal–organic framework. These materials exhibit a step in the adsorption isotherm indicative of a phase change. The pressure at which this step occurs is not only temperature dependent but is also metal center dependent. Likewise, the heats of adsorption vary depending on the metal center. Herein we demonstrate via quantum chemical calculations that the amines should not be considered firmly anchored to the framework and we explore the mechanism for CO 2 adsorption. An ammonium carbamate species ismore » formed via the insertion of CO 2 into the M–N amine bonds. Furthermore, we translate the quantum chemical results into isotherms using a coarse grained Monte Carlo simulation technique and show that this adsorption mechanism can explain the characteristic step observed in the experimental isotherm while a previously proposed mechanism cannot. Furthermore, metal analogues have been explored and the CO 2 binding energies show a strong metal dependence corresponding to the M–N amine bond strength. We show that this difference can be exploited to tune the pressure at which the step in the isotherm occurs. Additionally, the mmen–Ni 2(dobpdc) framework shows Langmuir like behavior, and our simulations show how this can be explained by competitive adsorption between the new model and a previously proposed model.« less

Quantum chemical study of relative reactivities of a series of amines and nitriles - Relevance to prebiotic chemistry

NASA Technical Reports Server (NTRS)

Loew, G. H.; Berkowitz, D.; Chang, S.

1975-01-01

Using the Iterative Extended Huckel Theory (IEHT) calculations of the electron distribution and orbital energies of a series of thirteen amines, nitriles and amino-nitriles relevant to prebiotic and cosmo-chemistry have been carried out. Ground state properties such as the energy and nature of the highest occupied (HOMO) and lowest empty (LEMO) molecular orbitals, net atomic charges and number of nonbonding electrons have been identified as criteria for correlating the relative nucleophilicity of amine and nitrile nitrogens and the electrophilicity of nitrile and other unsaturated carbon atoms. The results of such correlations can be partially verified by known chemical behavior of these compounds and are used to predict and understand their role in prebiotic organic synthesis.

Ruthenium-Catalyzed Aerobic Oxidation of Amines.

PubMed

Ray, Ritwika; Hazari, Arijit Singha; Lahiri, Goutam Kumar; Maiti, Debabrata

2018-01-18

Amine oxidation is one of the fundamental reactions in organic synthesis as it leads to a variety of value-added products such as oximes, nitriles, imines, and amides among many others. These products comprise the key N-containing building blocks in the modern chemical industry, and such transformations, when achieved in the presence of molecular oxygen without using stoichiometric oxidants, are much preferred as they circumvent the production of unwanted wastes. In parallel, the versatility of ruthenium catalysts in various oxidative transformations is well-documented. Herein, this review focuses on aerobic oxidation of amines specifically by using ruthenium catalysts and highlights the major achievements in this direction and challenges that still need to be addressed. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A reagent for safe and efficient diazo-transfer to primary amines: 2-azido-1,3-dimethylimidazolinium hexafluorophosphate.

PubMed

Kitamura, Mitsuru; Kato, So; Yano, Masakazu; Tashiro, Norifumi; Shiratake, Yuichiro; Sando, Mitsuyoshi; Okauchi, Tatsuo

2014-07-07

Organic azides were prepared from primary amines in high yields by a metal free diazo-transfer reaction using 2-azido-1,3-dimethylimidazolinium hexafluorophosphate (ADMP), which is safe and stable crystalline. The choice of base was important in the diazo-transfer reaction. In general, 4-(N,N-dimethyl)aminopyridine (DMAP) was efficient, but a stronger base such as alkylamine or DBU was more appropriate for the reaction of nucleophilic primary amines. X-ray single crystal structural analysis and geometry optimization using density functional theory (B3LYP/6-31G**) were conducted to study the ADMP structure, and the diazo-transfer reaction mechanism was explained with the help of the results of these analyses.

Direct Reaction of Amides with Nitric Oxide To Form Diazeniumdiolates

PubMed Central

2015-01-01

We report the apparently unprecedented direct reaction of nitric oxide (NO) with amides to generate ions of structure R(C=O)NH–N(O)=NO–, with examples including R = Me (1a) or 3-pyridyl (1b). The sodium salts of both released NO in pH 7.4 buffer, with 37 °C half-lives of 1–3 min. As NO-releasing drug candidates, diazeniumdiolated amides would have the advantage of generating only 1 equiv of base on hydrolyzing exhaustively to NO, in contrast to their amine counterparts, which generate 2 equiv of base. PMID:25210948

Method for separating water soluble organics from a process stream by aqueous biphasic extraction

DOEpatents

Chaiko, David J.; Mego, William A.

1999-01-01

A method for separating water-miscible organic species from a process stream by aqueous biphasic extraction is provided. An aqueous biphase system is generated by contacting a process stream comprised of water, salt, and organic species with an aqueous polymer solution. The organic species transfer from the salt-rich phase to the polymer-rich phase, and the phases are separated. Next, the polymer is recovered from the loaded polymer phase by selectively extracting the polymer into an organic phase at an elevated temperature, while the organic species remain in a substantially salt-free aqueous solution. Alternatively, the polymer is recovered from the loaded polymer by a temperature induced phase separation (cloud point extraction), whereby the polymer and the organic species separate into two distinct solutions. The method for separating water-miscible organic species is applicable to the treatment of industrial wastewater streams, including the extraction and recovery of complexed metal ions from salt solutions, organic contaminants from mineral processing streams, and colorants from spent dye baths.

Improving ready biodegradability testing of fatty amine derivatives.

PubMed

van Ginkel, C G; Gancet, C; Hirschen, M; Galobardes, M; Lemaire, Ph; Rosenblom, J

2008-09-01

This study assesses the biodegradation potential of a number of fatty amine derivatives in tests following the OECD guidelines for ready biodegradability. A number of methods are used to reduce toxicity and improve the bioavailability of the fatty amine derivatives in these tests. Alkyl-1,3-diaminopropanes and octadecyltrimethylammonium chloride are toxic to microorganisms at concentrations used in OECD ready biodegradability tests. The concentration of these fatty amine derivatives in the aqueous phase can be reduced by reacting humic, or lignosulphonic acids with the derivatives or through the addition of silica gel to the test bottles. Using these non-biodegradable substances, ready biodegradability test results were obtained with tallow-1,3-diaminopropane and octadecyltrimethylammonium chloride. Demonstration of the ready biodegradability of the water-insoluble dioctadecylamine under the prescribed standard conditions is almost impossible due to the limited bioavailability of this compound. However, ready biodegradability results were achieved by using very low initial test substance concentrations and by introducing an organic phase. The contents of the bottles used to assess the biodegradability of dioctadecylamine were always mixed. False negative biodegradability results obtained with the fatty amine derivatives studied are the result of toxic effects and/or limited bioavailability. The aids investigated therefore improve ready biodegradability testing.

Opposites Attract: Organic Charge Transfer Salts

ERIC Educational Resources Information Center

van de Wouw, Heidi L.; Chamorro, Juan; Quintero, Michael; Klausen, Rebekka S.

2015-01-01

A laboratory experiment is described that introduces second-year undergraduate organic chemistry students to organic electronic materials. The discovery of metallic conductivity in the charge transfer salt tetrathiafulvalene tetracyanoquinodimethane (TTF-TCNQ) is a landmark result in the history of organic electronics. The charge transfer…

Assembly of acid-functionalized single-walled carbon nanotubes at oil/water interfaces.

PubMed

Feng, Tao; Hoagland, David A; Russell, Thomas P

2014-02-04

The efficient segregation of water-soluble, acid-functionalized, single-walled carbon nanotubes (SWCNTs) at the oil/water interface was induced by dissolving low-molecular-weight amine-terminated polystyrene (PS-NH2) in the oil phase. Salt-bridge interactions between carboxylic acid groups of SWCNTs and amine groups of PS drove the assembly of SWCNTs at the interface, monitored by pendant drop tensiometry and laser scanning confocal microscopy. The impact of PS end-group functionality, PS and SWCNT concentrations, and the degree of SWCNT acid modification on the interfacial activity was assessed, and a sharp drop in interfacial tension was observed above a critical SWCNT concentration. Interfacial tensions were low enough to support stable oil/water emulsions. Further experiments, including potentiometric titrations and the replacement of SWCNTs by other carboxyl-containing species, demonstrated that the interfacial tension drop reflects the loss of SWCNT charge as the pH falls near/below the intrinsic carboxyl dissociation constant; species lacking multivalent carboxylic acid groups are inactive. The trapped SWCNTs appear to be neither ordered nor oriented.

Susceptibility of dry-cured tuna to oxidative deterioration and biogenic amines generation: I. Effect of NaCl content, antioxidant type and ageing.

PubMed

Roseiro, L C; Santos, C; Gonçalves, H; Serrano, C; Aleixo, C; Partidário, A; Lourenço, A R; Dias, M Abreu; da Ponte, D J B

2017-08-01

This study aimed to assess lipid oxidation and biogenic amine (BA) development in "muxama", a dry-cured tuna muscle product, as affected by salt content, antioxidant type and ageing time. Overall, BA contents decreased with NaCl level (2785.1mgkg -1 , 1148.1mgkg -1 and 307.7mgkg -1 ) and increased with ageing time (366.2mgkg -1 , 1711.8mgkg -1 and 2959.2mgkg -1 in the final product (T0), and after 1 (T1) and 3 (T3) months of ageing, respectively). Regardless of the test conditions, the most concentrated BA was always tyramine. For the ageing periods considered in the present study, malondialdehyde formation was affected by the NaCl level, with the saltiest samples exhibiting lower content. Rosemary and sage extracts represented promising technological options for preserving muxama from oxidation and to minimize the presence of a fishy flavour and odour, but this treatment may cause the colour to lose some of its redness and become less appealing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biogenic Amines in Raw and Processed Seafood

PubMed Central

Visciano, Pierina; Schirone, Maria; Tofalo, Rosanna; Suzzi, Giovanna

2012-01-01

The presence of biogenic amines (BAs) in raw and processed seafood, associated with either time/temperature conditions or food technologies is discussed in the present paper from a safety and prevention point of view. In particular, storage temperature, handling practices, presence of microbial populations with decarboxylase activity and availability of free amino acids are considered the most important factors affecting the production of BAs in raw seafood. On the other hand, some food technological treatments such as salting, ripening, fermentation, or marination can increase the levels of BAs in processed seafood. The consumption of high amount of BAs, above all histamine, can result in food borne poisoning which is a worldwide problem. The European Regulation established as maximum limits for histamine, in fishery products from fish species associated with high histidine amounts, values ranging from 100 to 200 mg/kg, while for products which have undergone enzyme maturation treatment in brine, the aforementioned limits rise to 200 and 400 mg/kg. Preventive measures and emerging methods aiming at controlling the production of BAs are also reported for potential application in seafood industries. PMID:22675321

Experimental and Theoretical Study of Molecular Response of Amine Bases in Organic Solvents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kathmann, Shawn M.; Cho, Herman M.; Chang, Tsun-Mei

2014-05-08

Reorientational correlation times of various amine bases (viz., pyridine, 2,6-lutidene, 2,2,6,6-tetramethylpiperidine) and organic solvents (dichloromethane, toluene) were determined by solution-state NMR relaxation time measurements and compared with predictions from molecular dynamics (MD) simulations. The bases and solvents are reagents in complex reactions involving Frustrated Lewis Pairs (FLP), which display remarkable catalytic activity in metal-free H2 scission. The comparison of measured and simulated correlation times is a key test of the ability of recent MD and quantum electronic structure calculations to elucidate the mechanism of FLP activity. Correla- tion times were found to be in the range 1.4-3.4 ps (NMR) andmore » 1.23-5.28 ps (MD) for the amines, and 0.9-2.3 ps (NMR) and 0.2-1.7 ps (MD) for the solvent molecules. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacic Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.« less

Synthesis and characterization of bifunctional surfaces with tunable functional group pairs

NASA Astrophysics Data System (ADS)

Galloway, John M.; Kung, Mayfair; Kung, Harold H.

2016-06-01

Grafting of pairs of functional groups onto a silica surface was demonstrated by tethering both terminals of an organochlorosilane precursor molecule, Cl2(CH3)Si(CH2)4(CO)(OSi(i-Pr)2)(CH2)2Si(CH3)Cl2, that possess a cleavable silyl ester bond, onto a silica surface. Hydrolytic cleavage of the silyl ester bond of the grafted molecule resulted in the generation of organized pairs of carboxylic acid and organosilanol groups. This organosilanol moiety was easily transformed into other functional groups through condensation reactions to form, together with the neighboring acid group, pairs such as carboxylic acid/secondary amine, carboxylic acid/pyridine, and carboxylic acid/phosphine. In the case of carboxylic acid/amine pairing, there was evidence of the formation of amide. A sample grafted with amine-carboxylic acid pairs was three times more active (per free amine) than a sample without such pairs for the nitroaldol condensation of 4-nitrobenzaldehyde and nitromethane.

A metalloenzyme-like catalytic system for the chemoselective oxidative cross-coupling of primary amines to imines under ambient conditions.

PubMed

Largeron, Martine; Fleury, Maurice-Bernard

2015-02-23

The direct oxidative cross-coupling of primary amines is a challenging transformation as homocoupling is usually preferred. We report herein the chemoselective preparation of cross-coupled imines through the synergistic combination of low loadings of Cu(II) metal-catalyst and o-iminoquinone organocatalyst under ambient conditions. This homogeneous cooperative catalytic system has been inspired by the reaction of copper amine oxidases, a family of metalloenzymes with quinone organic cofactors that mediate the selective oxidation of primary amines to aldehydes. After optimization, the desired cross-coupled imines are obtained in high yields with broad substrate scope through a transamination process that leads to the homocoupled imine intermediate, followed by dynamic transimination. The ability to carry out the reactions at room temperature and with ambient air, rather than molecular oxygen as the oxidant, and equimolar amounts of each coupling partner is particularly attractive from an environmentally viewpoint. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Click and chemically triggered declick reactions through reversible amine and thiol coupling via a conjugate acceptor

NASA Astrophysics Data System (ADS)

Diehl, Katharine L.; Kolesnichenko, Igor V.; Robotham, Scott A.; Bachman, J. Logan; Zhong, Ye; Brodbelt, Jennifer S.; Anslyn, Eric V.

2016-10-01

The coupling and decoupling of molecular units is a fundamental undertaking of organic chemistry. Herein we report the use of a very simple conjugate acceptor, derived from Meldrum's acid, for the sequential ‘clicking’ together of an amine and a thiol in aqueous conditions at neutral pH. Subsequently, this linkage can be ‘declicked’ by a chemical trigger to release the original amine and thiol undisturbed. The reactivity differs from that of other crosslinking agents because the selectivity for sequential functionalization derives from an altering of the electrophilicity of the conjugate acceptor on the addition of the amine. We describe the use of the procedure to modify proteins, create multicomponent libraries and synthesize oligomers, all of which can be declicked to their starting components in a controlled fashion when desired. Owing to the mild reaction conditions and ease of use in a variety of applications, the method is predicted to have wide utility.

Using black soldier fly larvae for processing organic leachates.

PubMed

Popa, Radu; Green, Terrence R

2012-04-01

A large number of biodegradable byproducts including alcohols, soluble saccharides, volatile organic acids, and amines accumulate in the liquid fraction (leachate) produced as vegetal and food scrap waste decomposes. Untreated leachate, because it is rich in nutrients and organic byproducts, has a high chemical oxygen demand and is normally cleared of soluble organic byproducts by mineralization before its discharge into waterways. Mineralizing leachates using chemical and microbial biotechnologies is, however, a lengthy and costly process. We report here that the larvae of the black soldier fly Hermetia illucens (L.) (Diptera: Stratiomyidae), an insect rich in protein and lipids, and having significant commercial value, while feeding and growing off of compost leachate, lowers its chemical oxygen demand relative to that of leachate unexposed to larvae, neutralizes its acidity, and clears it of volatile organic acids, amines, and alcohols. These observations demonstrate that black soldier fly larvae could be used to help offset the cost and clean up of organic solutes in leachate waste streams while recycling carbon, nitrogen, and phosphate into usable and commercially valuable biomass.

On the applicability of a hybrid bioreactor operated with polymeric tubing for the biological treatment of saline wastewater.

PubMed

Tomei, M Concetta; Mosca Angelucci, Domenica; Stazi, Valentina; Daugulis, Andrew J

2017-12-01

Effective biological treatment of high salt content wastewater requires consideration of both salt and organic toxicity. This study treated a synthetic saline wastewater containing NaCl (100gL -1 ) and 2,4-dimethylphenol (1.2gL -1 ) with a hybrid system consisting of a biological reactor containing spiral-coiled polymeric tubing through which the mixed feed was pumped. The tubing wall was permeable to the organic contaminant, but not to the salt, which allowed transfer of the organic into the cell-containing bioreactor contents for degradation, while not exposing the cells to high salt concentrations. Different grades of DuPont Hytrel polymer were examined on the basis of organic affinity predictions and experimental partition and mass transfer tests. Hytrel G3548 tubing showed the highest permeability for 2,4-dimethylphenol while exerting an effective salt barrier, and was used to verify the feasibility of the proposed system. Very high organic removal (99% after just 5h of treatment) and effective biodegradation of the organic fraction of the wastewater (>90% at the end of the test) were observed. Complete salt separation from the microbial culture was also achieved. Copyright © 2017 Elsevier B.V. All rights reserved.

Non-enzymatic palladium recovery on microbial and synthetic surfaces.

PubMed

Rotaru, Amelia-Elena; Jiang, Wei; Finster, Kai; Skrydstrup, Troels; Meyer, Rikke Louise

2012-08-01

The use of microorganisms as support for reduction of dissolved Pd(II) to immobilized Pd(0) nanoparticles is an environmentally friendly approach for Pd recovery from waste. To better understand and engineer Pd(0) nanoparticle synthesis, one has to consider the mechanisms by which Pd(II) is reduced on microbial surfaces. Escherichia coli, Shewanella oneidensis, and Pseudomonas putida were used as model organisms in order to elucidate the role of microbial cells in Pd(II) reduction under acidic conditions. Pd(II) was reduced by formate under acidic conditions, and the process occurred substantially faster in the presence of cells as compared to cell-free controls. We found no difference between native (untreated) and autoclaved cells, and could demonstrate that even a non-enzymatic protein (bovine serum albumin) stimulated Pd(II) reduction as efficiently as bacterial cells. Amine groups readily interact with Pd(II), and to specifically test their role in surface-assisted Pd(II) reduction by formate, we replaced bacterial cells with polystyrene microparticles functionalized with amine or carboxyl groups. Amine-functionalized microparticles had the same effect on Pd(II) reduction as bacterial cells, and the effect could be hampered if the amine groups were blocked by acetylation. The interaction with amine groups was confirmed by infrared spectroscopy on whole cells and amine-functionalized microparticles. In conclusion, bio-supported Pd(II) reduction on microbial surfaces is possibly mediated by a non-enzymatic mechanism. We therefore suggest the use of amine-rich biomaterials rather than intact cells for Pd bio-recovery from waste. Copyright © 2012 Wiley Periodicals, Inc.

Silica nanoparticles and biological dispersants: genotoxic effects on A549 lung epithelial cells

NASA Astrophysics Data System (ADS)

Brown, David M.; Varet, Julia; Johnston, Helinor; Chrystie, Alison; Stone, Vicki

2015-10-01

Silica nanoparticle exposure could be intentional (e.g. medical application or food) or accidental (e.g. occupational inhalation). On entering the body, particles become coated with specific proteins depending on the route of entry. The ability of silica particles of different size and charge (non-functionalized 50 and 200 nm and aminated 50 and 200 nm) to cause genotoxic effects in A549 lung epithelial cells was investigated. Using the modified comet assay and the micronucleus assay, we examined the effect of suspending the particles in different dispersion media [RPMI or Hanks' balanced salt solution (HBSS), supplemented with bovine serum albumin (BSA), lung lining fluid (LLF) or serum] to determine if this influenced the particle's activity. Particle characterisation suggested that the particles were reasonably well dispersed in the different media, with the exception of aminated 50 nm particles which showed evidence of agglomeration. Plain 50, 200 nm and aminated 50 nm particles caused significant genotoxic effects in the presence of formamidopyrimidine-DNA glycosylase when dispersed in HBSS or LLF. These effects were reduced when the particles were dispersed in BSA and serum. There was no significant micronucleus formation produced by any of the particles when suspended in any of the dispersants. The data suggest that silica particles can produce a significant genotoxic effect according to the comet assay in A549 cells, possibly driven by an oxidative stress-dependent mechanism which may be modified depending on the choice of dispersant employed.

Aerobic biodegradation of amines in industrial saline wastewaters.

PubMed

Campo, Pablo; Platten, William; Suidan, Makram T; Chai, Yunzhou; Davis, John W

2011-11-01

The treatment of hypersaline wastewaters represents a challenge since high salt concentrations disrupt bacteria present in normal biological treatments. This study was conducted to determine the fate of amines in two hypersaline wastewaters obtained from an industrial treatment plant processing influents with 3% and 7% of NaCl. The compounds were aniline (ANL), 4,4'-methylenedianiline (4,4'-MDA), cyclohexylamine (CHA), N-(2-aminoethyl)ethanolamine (AEA), N,N-diethylethanolamine (DEA), N,N-bis(2-hydroxyethyl)methylamine (MDEA), and tris(2-hydroxyethyl)amine (TEA). Mixtures of these chemicals with a mixed liquor suspended solids concentration of 1000 mg L(-1) were prepared at two salinities (3% and 7% NaCl). Ethanolamines were readily biodegraded at both salinities, following first-order kinetics with half-lives ranging between 10 and 58 h. Hydroxyl groups present in the ethanolamines had a positive impact on the biodegradation. Salinity did not affect the biodegradation rate of TEA and MDEA, whereas AEA and DEA degraded faster in 3% NaCl. After 48h, CHA was metabolized within a 24-h period in 3% NaCl, while no degradation was observed in 7% NaCl. ANL exhibited lag phases in both salinities and, in the following 24-h period, ANL concentrations dropped 40% and disappeared after 48 h. 4,4'-MDA degraded in 3% NaCl (half-life of 123 h) and remained unaltered after 120 h in 7% NaCl. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Azomethine Ylide Route to Amine C–H Functionalization: Redox-Versions of Classic Reactions and a Pathway to New Transformations

PubMed Central

2016-01-01

Conspectus Redox-neutral methods for the functionalization of amine α-C–H bonds are inherently efficient because they avoid external oxidants and reductants and often do not generate unwanted byproducts. However, most of the current methods for amine α-C–H bond functionalization are oxidative in nature. While the most efficient variants utilize atmospheric oxygen as the terminal oxidant, many such transformations require the use of expensive or toxic oxidants, often coupled with the need for transition metal catalysts. Redox-neutral amine α-functionalizations that involve intramolecular hydride transfer steps provide viable alternatives to certain oxidative reactions. These processes have been known for some time and are particularly well suited for tertiary amine substrates. A mechanistically distinct strategy for secondary amines has emerged only recently, despite sharing common features with a range of classic organic transformations. Among those are such widely used reactions as the Strecker, Mannich, Pictet–Spengler, and Kabachnik–Fields reactions, Friedel–Crafts alkylations, and iminium alkynylations. In these classic processes, condensation of a secondary amine with an aldehyde (or a ketone) typically leads to the formation of an intermediate iminium ion, which is subsequently attacked by a nucleophile. The corresponding redox-versions of these transformations utilize identical starting materials but incorporate an isomerization step that enables α-C–H bond functionalization. Intramolecular versions of these reactions include redox-neutral amine α-amination, α-oxygenation, and α-sulfenylation. In all cases, a reductive N-alkylation is effectively combined with an oxidative α-functionalization, generating water as the only byproduct. Reactions are promoted by simple carboxylic acids and in some cases require no additives. Azomethine ylides, dipolar species whose usage is predominantly in [3 + 2] cycloadditions and other pericyclic processes, have been identified as common intermediates. Extension of this chemistry to amine α,β-difunctionalization has been shown to be possible by way of converting the intermediate azomethine ylides into transient enamines. This Account details the evolution of this general strategy and the progress made to date. Further included is a discussion of related decarboxylative reactions and transformations that result in the redox-neutral aromatization of (partially) saturated cyclic amines. These processes also involve azomethine ylides, reactive intermediates that appear to be far more prevalent in condensation chemistry of amines and carbonyl compounds than previously considered. In contrast, as exemplified by some redox transformations that have been studied in greater detail, iminium ions are not necessarily involved in all amine/aldehyde condensation reactions. PMID:25560649

The azomethine ylide route to amine C-H functionalization: redox-versions of classic reactions and a pathway to new transformations.

PubMed

Seidel, Daniel

2015-02-17

Conspectus Redox-neutral methods for the functionalization of amine α-C-H bonds are inherently efficient because they avoid external oxidants and reductants and often do not generate unwanted byproducts. However, most of the current methods for amine α-C-H bond functionalization are oxidative in nature. While the most efficient variants utilize atmospheric oxygen as the terminal oxidant, many such transformations require the use of expensive or toxic oxidants, often coupled with the need for transition metal catalysts. Redox-neutral amine α-functionalizations that involve intramolecular hydride transfer steps provide viable alternatives to certain oxidative reactions. These processes have been known for some time and are particularly well suited for tertiary amine substrates. A mechanistically distinct strategy for secondary amines has emerged only recently, despite sharing common features with a range of classic organic transformations. Among those are such widely used reactions as the Strecker, Mannich, Pictet-Spengler, and Kabachnik-Fields reactions, Friedel-Crafts alkylations, and iminium alkynylations. In these classic processes, condensation of a secondary amine with an aldehyde (or a ketone) typically leads to the formation of an intermediate iminium ion, which is subsequently attacked by a nucleophile. The corresponding redox-versions of these transformations utilize identical starting materials but incorporate an isomerization step that enables α-C-H bond functionalization. Intramolecular versions of these reactions include redox-neutral amine α-amination, α-oxygenation, and α-sulfenylation. In all cases, a reductive N-alkylation is effectively combined with an oxidative α-functionalization, generating water as the only byproduct. Reactions are promoted by simple carboxylic acids and in some cases require no additives. Azomethine ylides, dipolar species whose usage is predominantly in [3 + 2] cycloadditions and other pericyclic processes, have been identified as common intermediates. Extension of this chemistry to amine α,β-difunctionalization has been shown to be possible by way of converting the intermediate azomethine ylides into transient enamines. This Account details the evolution of this general strategy and the progress made to date. Further included is a discussion of related decarboxylative reactions and transformations that result in the redox-neutral aromatization of (partially) saturated cyclic amines. These processes also involve azomethine ylides, reactive intermediates that appear to be far more prevalent in condensation chemistry of amines and carbonyl compounds than previously considered. In contrast, as exemplified by some redox transformations that have been studied in greater detail, iminium ions are not necessarily involved in all amine/aldehyde condensation reactions.

Recovery of uranium values

DOEpatents

Brown, K. B.; Crouse, Jr., D. J.; Moore, J. G.

1959-03-10

A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine fn the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected anine dissolved in a nonpolar waterimmiscible organfc solvent such as kerosene. The uranium which is substantially completely extracted by the organic phase may be stripped therefrom by water, and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

Csbnd N bond formation in alicyclic and heterocyclic compounds by amine-modified nanoclay

NASA Astrophysics Data System (ADS)

Zarnegar, Zohre; Alizadeh, Roghayeh; Ahmadzadeh, Majid; Safari, Javad

2017-09-01

In the current protocol, amine functionalized montmorillonite K10 nanoclay (NH2-MMT) was applied to catalyze the formation of Csbnd N bonds in the synthesis of azines and 2-aminothiazoles at room temperature. In comparison with the current methods of Csbnd N bond formation, this approach displays specific advantages include atom economy, clean conversion, design for energy efficiency, the use of nontoxic and heterogeneous catalyst, higher purity and yields, safer solvent and reagents for this organic transformation.

Inaugural Maximum Values for Sodium in Processed Food Products in the Americas.

PubMed

Campbell, Norm; Legowski, Barbara; Legetic, Branka; Nilson, Eduardo; L'Abbé, Mary

2015-08-01

Reducing dietary salt/sodium is one of the most cost-effective interventions to improve population health. There are five initiatives in the Americas that independently developed targets for reformulating foods to reduce salt/sodium content. Applying selection criteria, recommended by the Pan American Health Organization (PAHO)/World Health Organization (WHO) Technical Advisory Group on Dietary Salt/Sodium Reduction, a consortium of governments, civil society, and food companies (the Salt Smart Consortium) agreed to an inaugural set of regional maximum targets (upper limits) for salt/sodium levels for 11 food categories, to be achieved by December 2016. Ultimately, to substantively reduce dietary salt across whole populations, targets will be needed for the majority of processed and pre-prepared foods. Cardiovascular and hypertension organizations are encouraged to utilize the regional targets in advocacy and in monitoring and evaluation of progress by the food industry. © 2015 Wiley Periodicals, Inc.

Enhanced Adsorption of p-Arsanilic Acid from Water by Amine-Modified UiO-67 as Examined Using Extended X-ray Absorption Fine Structure, X-ray Photoelectron Spectroscopy, and Density Functional Theory Calculations.

PubMed

Tian, Chen; Zhao, Jian; Ou, Xinwen; Wan, Jieting; Cai, Yuepeng; Lin, Zhang; Dang, Zhi; Xing, Baoshan

2018-03-20

p-Arsanilic acid ( p-ASA) is an emerging organoarsenic pollutant comprising both inorganic and organic moieties. For the efficient removal of p-ASA, adsorbents with high adsorption affinity are urgently needed. Herein, amine-modified UiO-67 (UiO-67-NH 2 ) metal-organic frameworks (MOFs) were synthesized, and their adsorption affinities toward p-ASA were 2 times higher than that of the pristine UiO-67. Extended X-ray absorption fine structure (EXAFS), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculation results revealed adsorption through a combination of As-O-Zr coordination, hydrogen bonding, and π-π stacking, among which As-O-Zr coordination was the dominant force. Amine groups played a significant role in enhancing the adsorption affinity through strengthening the As-O-Zr coordination and π-π stacking, as well as forming new adsorption sites via hydrogen bonding. UiO-67-NH 2 s could remove p-ASA at low concentrations (<5 mg L -1 ) in simulated natural and wastewaters to an arsenic level lower than that of the drinking water standard of World Health Organization (WHO) and the surface water standard of China, respectively. This work provided an emerging and promising method to increase the adsorption affinity of MOFs toward pollutants containing both organic and inorganic moieties, via modifying functional groups based on the pollutant structure to achieve synergistic adsorption effect.

Solvothermal synthesis of a new 3-D mixed-metal sulfide framework, (H1.33tren)[In2.67Sb1.33S8]·tren

NASA Astrophysics Data System (ADS)

Lampkin, John D.; Powell, Anthony V.; Chippindale, Ann M.

2016-11-01

A new indium(III) antimony(V) sulfide, (H1.33tren)[In2.67Sb1.33S8]·tren, has been prepared solvothermally at 433 K. The compound crystallises in the tetragonal space group I-42d (lattice parameters, a=12.6248(5) and c=19.4387(18) Å at 150 K) and contains adamantane-like T2 supertetrahedral units comprised of corner-sharing InS45- and SbS43- tetrahedra. The adamantane-like units are then linked through sulfur vertices to generate an open, 3-D framework structure containing large pores in which neutral, protonated tren (tris(2-aminoethylene)amine) molecules reside. The presence of the organic components was confirmed by solid-state 13C NMR (10 kHz), combustion and thermogravimetric analysis. The band gap, obtained from UV-vis diffuse reflectance measurements, is 2.7(2) eV. Stirring with either water or alkali-metal salt solution leads to removal of the neutral tren molecules and an 9% reduction in unit-cell volume on formation of (H1.33tren)[In2.67Sb1.33S8]·(H2O)4.

Thiolsubtilisin acts as an acetyltransferase in organic solvents.

PubMed

Tai, Dar Fu; Liaw, Wen Chen

2002-04-24

The catalytic mechanism of arylamine N-acetyltransferase has been proposed to involve Cys-His-Asp as its catalytic triad. Thiolsubtilisin, a chemically modified enzyme that has a catalytic triad of Cys-His-Asp at the active site, mimics the catalysis of arylamine N-acetyltransferase, serotonin N-acetyltransferase, histone N-acetyltransferase and amino acid N-acetyltransferase. Thiolsubtilisin not only can catalyze amino acid transacetylation, but is also able to catalyze amine transacetylation. Ethyl acetate was used as the acylating reagent to form N-acetyl amino acids and amines in organic solvents with moderate yield. Hence, these findings broaden our understanding of the structural features required for N-acetyltransferases activity as well as provide a structural relationship between cysteine protease and other N-acyltransferases.

Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

NASA Astrophysics Data System (ADS)

Jing, Bo; Wang, Zhen; Tan, Fang; Guo, Yucong; Tong, Shengrui; Wang, Weigang; Zhang, Yunhong; Ge, Maofa

2018-04-01

While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO3)2) and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA). The nitrate salt / organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH), the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

Antiplaque and antigingivitis toothpastes.

PubMed

Sanz, Mariano; Serrano, Jorge; Iniesta, Margarita; Santa Cruz, Isabel; Herrera, David

2013-01-01

Dentifrices are a general term used to describe preparations that are used together with a toothbrush with the purpose to clean and/or polish the teeth. Active toothpastes were first formulated in the 1950s and included ingredients such as urea, enzymes, ammonium phosphate, sodium lauryl sarcosinate and stannous fluoride. Later, therapeutic agents were included. Today's toothpastes have two objectives: to help the toothbrush in cleaning the tooth surface and to provide a therapeutic effect. The therapeutic effect may have an antiplaque or anti-inflammatory basis when the nature of the agents is antimicrobial. Plaque inhibitory and antiplaque activity of toothpastes used for chemical plaque control is evaluated in distinct consecutive stages, the last being home use randomized clinical trials of at least 6 months' duration. In this chapter, the scientific evidence supporting the use of the most common antiplaque agents, included in toothpaste formulations, is reviewed, with a special emphasis on 6-month clinical trials, and systematic reviews with meta-analyses of the mentioned studies. Among the active agents, the following have been included in toothpastes: enzymes, amine alcohols, herbal or natural products, triclosan, bisbiguanides (chlorhexidine), quaternary ammonium compounds (cetylpyridinium chloride) and different metal salts (zinc salts, stannous fluoride, stannous fluoride with amine fluoride). Dentifrices are the ideal vehicles for any active ingredient used as an oral health preventive measure since they are used in combination with toothbrushing, which is the most frequently employed oral hygiene method. The most important indications of dentifrices with active ingredients are associated with long-term use to prevent bacterial biofilm formation, mostly in gingivitis patients or in patients on supportive periodontal therapy. Copyright © 2013 S. Karger AG, Basel.

In vitro and in vivo impact of silica nanoparticle design on biocompatibility

NASA Astrophysics Data System (ADS)

Yu, Tian

Silica nanoparticles (SiO2) have utility in a wide range of applications, such as biologic delivery platforms, imaging and diagnostic agents, and targeted therapeutic carriers. Recent improvements in regulating the geometry, porosity, and surface characteristics of SiO2 have further facilitated their biomedical applications. Concerns however remain about the toxic effects of SiO2 upon exposure to biological systems. The impacts of geometry, porosity, and surface characteristics of SiO 2 on cellular toxicity and hemolytic activity were explored. It was shown that surface characteristics and porosity govern cellular toxicity. The cellular association of SiO2 increased in the following order: mesoporous SiO2 (aspect ratio 1, 2, 4, 8) < amine-modified mesoporous SiO2 (aspect ratio 1, 2, 4, 8) < amine-modified nonporous Stober SiO2 < nonporous Stober SiO2. Geometry did not seem to influence the extent of SiO2 cellular association. Hemolysis assay showed that the hemolytic activity was porosity- and geometry-dependent for pristine SiO2 and surface charge-dependent for amine-modified SiO2. The acute toxicity, biodistribution, and pharmacokinetics of SiO 2 of systematically varied geometry, porosity, and surface characteristics were evaluated in immune-competent mice when administered intravenously. Results suggest that in vivo toxicity, biodistribution and pharmacokinetics of SiO2 were mainly influenced by nanoparticle porosity and surface characteristics. The maximum tolerated dose (MTD) increased in the following order: Mesoporous SiO2 (aspect ratio 1, 2, 8) at 30 -- 65 mg/kg < amine-modified mesoporous SiO2 (aspect ratio 1, 2, 8) at 100 -- 150 mg/kg < unmodified or amine-modified nonporous SiO2 at 450 mg/kg. The adverse reactions above MTDs were primarily caused by the mechanical obstruction of SiO2 in the vasculature that led to congestion in multiple vital organs and subsequent organ failure. The nanoparticles were taken up extensively by the liver and spleen. Mesoporous SiO2 exhibited higher accumulation in the lung than nonporous SiO 2 of similar size. This accumulation was reduced by primary amine modification. Increasing the aspect ratio of amine-modified mesoporous SiO2 from 1 to 8 resulted in increased accumulation in the lung. These studies provide critical guidelines in rational design of SiO 2 for nanomedicine applications.

The Industrial Age of Biocatalytic Transamination.

PubMed

Fuchs, Michael; Farnberger, Judith E; Kroutil, Wolfgang

2015-11-01

During the last decade the use of ω-transaminases has been identified as a very powerful method for the preparation of optically pure amines from the corresponding ketones. Their immense potential for the preparation of chiral amines, together with their ease of use in combination with existing biocatalytic methods, have made these biocatalysts a competitor to any chemical methodology for (asymmetric) amination. An increasing number of examples, especially from industry, shows that this biocatalytic technology outmaneuvers existing chemical processes by its simple and flexible nature. In the last few years numerous publications and patents on synthetic routes, mainly to pharmaceuticals, involving ω-transaminases have been published. The review gives an overview of the application of ω-transaminases in organic synthesis with a focus on active pharmaceutical ingredients (APIs) and the developments during the last few years.

Visible-light-driven Efficient Photocatalytic Reduction of Organic Azides to Amines over CdS Sheet-rGO Nanocomposite.

PubMed

Singha, Krishnadipti; Mondal, Aniruddha; Ghosh, Subhash Chandra; Panda, Asit Baran

2018-02-02

CdS sheet-rGO nanocomposite as a heterogeneous photocatalyst enables visible-light-induced photocatalytic reduction of aromatic, heteroaromatic, aliphatic and sulfonyl azides to the corresponding amines using hydrazine hydrate as a reductant. The reaction shows excellent conversion and chemoselectivity towards the formation of the amine without self-photoactivated azo compounds. In the adopted strategy, CdS not only accelerates the formation of nitrene through photoactivation of azide but also enhances the decomposition of azide to a certain extent, which entirely suppressed formation of the azo compound. The developed CdS sheet-rGO nanocomposite catalyst is very active, providing excellent results under irradiation with a 40 W simple household CFL lamp. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Proton affinities of hydrated molecules

NASA Astrophysics Data System (ADS)

Valadbeigi, Younes

2016-09-01

Proton affinities (PA) of non-hydrated, M, and hydrated forms, M(H2O)1,2,3, of 20 organic molecules including alcohols, ethers, aldehydes, ketones and amines were calculated by the B3LYP/6-311++G(d,p) method. For homogeneous families, linear correlations were observed between PAs of the M(H2O)1,2,3 and the PAs of the non-hydrated molecules. Also, the absolute values of the hydration enthalpies of the protonated molecules decreased linearly with the PAs. The correlation functions predicted that for an amine with PA < 1100 kJ/mol the PA(M(H2O)) is larger than the corresponding PA, while for an amine with PA > 1100 kJ/mol the PA(M(H2O)) is smaller than the PA.

Pyrene-based bisazolium salts: from luminescence properties to janus-type bis-N-heterocyclic carbenes.

PubMed

Gonell, Sergio; Poyatos, Macarena; Peris, Eduardo

2014-07-28

A series of pyrene-based bisazolium salts have been obtained starting from 4,5,9,10-tetrabromo-2,7-di-tert-butylpyrene. The synthetic procedure to the pyrene-bisazoliums (PBIs) reveals an unexpected behavior, as a consequence of the presence of the alkyl groups (alkyl=Me, Et, n-Pr, and n-Bu) coming from the trisalkoxyformate in the final products, instead of the expected tBu of tAmyl groups from the starting tetra-aminated pyrenes. All bisazoliums show fluorescence properties, with emissions in the range of 370-420 nm, and quantum yields ranging from 0.29 to 0.41. The PBIs were used as bis-NHC precursors in the preparation of a series of dirhodium and diiridium complexes, which have been fully characterized. The electrochemical studies on selected dimetallic complexes reveal that the electronic communication between the metals through the polyaromatic linker is negligible. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isolation of nonvolatile, organic solutes from natural waters by zeotrophic distillation of water from N,N-dimethylformamide

USGS Publications Warehouse

Leenheer, J.A.; Brown, P.A.; Stiles, E.A.

1987-01-01

Nonvolatile, organic solutes that comprise the dissolved organic carbon (DOC) in saline waters were isolated by removal of the water by distillation from a N,N-dimethylformamideformic acid-acetonitrile mixture. Salts isolated with the DOC were removed by crystallization of sodium chloride and sodium sulfate from the solvent mixture, removal of silicic acid by acidification and precipitation, removal of boric acid by methylation and volatilization, and removal of phosphate by zinc acetate precipitation. Chemical alteration of the organic solutes was minimized during evaporative concentration steps by careful control of acid concentrations in the solvent mixture and was minimized during drying by conversion of the samples to pyridinium and sodium salts. Recoveries of various hydrophilic organic standards from aqueous salt solutions and recoveries of natural organic solutes from various water samples varied from 60 to 100%. Losses of organic solutes during the isolation procedure were nonselective and related to the number of salt- and precipitate-washing cycles in the procedure.

Amine-Catalyzed Isomerization of Diethylmaleate to Diethylfumarate.

ERIC Educational Resources Information Center

Glover, Irving T.; And Others

1978-01-01

This reaction is used in an introductory organic chemistry course to illustrate principles of gas-liquid chromatography, geometrical isomerism, homogeneous catalysis, and activation energy determinations. (BB)

Synthesis and Metalation of a Ligand: An Interdisciplinary Laboratory Experiment for Second-Year Organic and Introductory Inorganic Chemistry Students

ERIC Educational Resources Information Center

Kasting, Benjamin J.; Bowser, Andrew K.; Anderson-Wile, Amelia M.; Wile, Bradley M.

2015-01-01

An interdisciplinary laboratory experiment involving second-year undergraduate organic chemistry and introductory inorganic chemistry undergraduate students is described. Organic chemistry students prepare a series of amine-bis(phenols) via a Mannich reaction, and characterize their products using melting point; FTIR; and [superscript 1]H,…

[Determination of carcinogenic aromatic amines derived from azo colorants in plastic components of electrical and electronic products by high performance liquid chromatography-mass spectrometry].

PubMed

Niu, Zengyuan; Luo, Xin; Ye, Xiwen; Wang, Huihui; Li, Jingying

2014-01-01

A study for the simultaneous determination of 21 primary aromatic amines derived from the reduction of the azo colorants in plastic components of electrical and electronic products was conducted. Organic solvents were used to dissolve or swell the plastics to release the azo dyes existing in the plastic components. The azo colorants were reduced to aromatic amines under strong reducing condition of dithionite. Aromatic amines were extracted with methyl tert-butyl ether. Methanol-water (1: 1, v/v) was used to concentrate the extract to constant-volume for HPLC-MS analysis. The analytes were separated on a ZORBAX Eclipse XDB C18 column using the gradient elution with acetonitrile and 0.1% (v/v) formic acid aqueous solution at a flow rate of 0.6 mL/min. The analyte confirmation was performed using retention time and characteristic ions in selected ion monitoring (SIM) mode. The correlation coefficients (r) of all the standard curves were more than 0.998, and the limits of quantification of the analytes were 0.5 mg/kg. The recoveries were 60.1% - 129.5% for the 21 aromatic amines with the RSDs not more than 14.0% except for a few compounds. The results showed that the banned azo colorants in the plastic products can be analyzed qualitatively and quantitatively through reductive conversion into aromatic amines. In addition, this method has high accuracy and good precision.

Treatment of organic waste

DOEpatents

Grantham, LeRoy F.

1979-01-01

An organic waste containing at least one element selected from the group consisting of strontium, cesium, iodine and ruthenium is treated to achieve a substantial reduction in the volume of the waste and provide for fixation of the selected element in an inert salt. The method of treatment comprises introducing the organic waste and a source of oxygen into a molten salt bath maintained at an elevated temperature to produce solid and gaseous reaction products. The gaseous reaction products comprise carbon dioxide and water vapor, and the solid reaction products comprise the inorganic ash constituents of the organic waste and the selected element which is retained in the molten salt. The molten salt bath comprises one or more alkali metal carbonates, and may optionally include from 1 to about 25 wt.% of an alkali metal sulfate.

Plasmachemical synthesis of nanopowders of yttria and zirconia from dispersed water-salt-organic mixtures

NASA Astrophysics Data System (ADS)

Novoselov, Ivan; Karengin, Alexander; Shamanin, Igor; Alyukov, Evgeny; Gusev, Alexander

2018-03-01

Article represents results on theoretical and experimental research of yttria and zirconia plasmachemical synthesis in air plasma from water-salt-organic mixtures "yttrium nitrate-water-acetone" and "zirconyl nitrate-water-acetone". On the basis of thermotechnical calculations the influence of organic component on lower heat value and adiabatic combustion temperature of water-salt-organic mixtures as well as compositions of mixtures providing their energy-efficient plasma treatment were determined. The calculations found the influence of mass fraction and temperature of air plasma supporting gas on the composition of plasma treatment products. It was determined the conditions providing yttria and zirconia plasmachemical synthesis in air plasma. During experiments it was b eing carried out the plasmachemical synthesis of yttria and zirconia powders in air plasma flow from water -salt-organic mixtures. Analysis of the results for obtained powders (scanning electron microscopy, X-ray diffraction analysis, BET analysis) confirm nanostructure of yttria and zirconia.

Modeling the surface tension of complex, reactive organic-inorganic mixtures

NASA Astrophysics Data System (ADS)

Schwier, A. N.; Viglione, G. A.; Li, Z.; McNeill, V. F.

2013-01-01

Atmospheric aerosols can contain thousands of organic compounds which impact aerosol surface tension, affecting aerosol properties such as cloud condensation nuclei (CCN) ability. We present new experimental data for the surface tension of complex, reactive organic-inorganic aqueous mixtures mimicking tropospheric aerosols. Each solution contained 2-6 organic compounds, including methylglyoxal, glyoxal, formaldehyde, acetaldehyde, oxalic acid, succinic acid, leucine, alanine, glycine, and serine, with and without ammonium sulfate. We test two surface tension models and find that most reactive, complex, aqueous organic mixtures which do not contain salt are well-described by a weighted Szyszkowski-Langmuir (S-L) model which was first presented by Henning et al. (2005). Two approaches for modeling the effects of salt were tested: (1) the Tuckermann approach (an extension of the Henning model with an additional explicit salt term), and (2) a new implicit method proposed here which employs experimental surface tension data obtained for each organic species in the presence of salt used with the Henning model. We recommend the use of method (2) for surface tension modeling because the Henning model (using data obtained from organic-inorganic systems) and Tuckermann approach provide similar modeling fits and goodness of fit (χ2) values, yet the Henning model is a simpler and more physical approach to modeling the effects of salt, requiring less empirically determined parameters.

Energy densification of biomass-derived organic acids

DOEpatents

Wheeler, M. Clayton; van Walsum, G. Peter; Schwartz, Thomas J.; van Heiningen, Adriaan

2013-01-29

A process for upgrading an organic acid includes neutralizing the organic acid to form a salt and thermally decomposing the resulting salt to form an energy densified product. In certain embodiments, the organic acid is levulinic acid. The process may further include upgrading the energy densified product by conversion to alcohol and subsequent dehydration.

Lanthanum(III)-catalyzed disproportionation of hydrogen peroxide: a heterogeneous generator of singlet molecular oxygen-1O2 (1Deltag)-in near-neutral aqueous and organic media for peroxidation of electron-rich substrates.

PubMed

Nardello, Véronique; Barbillat, Jacques; Marko, Jean; Witte, Peter T; Alsters, Paul L; Aubry, Jean-Marie

2003-01-20

The decomposition of hydrogen peroxide into singlet molecular oxygen-(1)O(2) ((1)Delta(g))-in the presence of lanthanum(iii) salts was studied by monitoring its characteristic IR luminescence at 1270 nm. The process was found to be heterogeneously catalyzed by La(III), provided that the heterogeneous catalyst is generated in situ. The yield of (1)O(2) generation was assessed as 45+/-5 % both in water and in methanol. The pH-dependence on the rate of (1)O(2) generation corresponds to a bell-shaped curve from pH 4.5 to 13 with a maximum around pH 8. The study of the influence of H(2)O(2) showed that the formation of (1)O(2) begins as soon as one equivalent of H(2)O(2) is introduced. It then increases drastically up to two equivalents and more smoothly above. Unlike all other metal salt catalyst systems known to date for H(2)O(2) disproportionation, this chemical source of (1)O(2) is able to generate (1)O(2) not only in basic media, but also under neutral and slightly acidic conditions. In addition, this La-based catalyst system has a very low tendency to induce unwanted oxygenating side reactions, such as epoxidation of alkenes. These two characteristics of the heterogeneous lanthanum catalyst system allow non-photochemical (i.e., "dark") singlet oxygenation of substrate classes that cannot be peroxidized successfully with conventional molybdate catalysts, such as allylic alcohols and alkenyl amines.

Nanohybrids of magnetic iron-oxide particles in hydrophobic organoclays for oil recovery.

PubMed

Hsu, Ru-Siou; Chang, Wen-Hsin; Lin, Jiang-Jen

2010-05-01

Nanohybrids with magnetic iron-oxide nanoparticles (FeNPs) embedded in the multilayered silicate clay were synthesized by in situ Fe(2+)/Fe(3+) coprecipitation. The natural clay, sodium montmorillonite (Na(+)-MMT), was first modified with hydrophobic poly(oxypropylene)amine salts (POP at 2000 and 4000 g/mol M(w)). The two POP-intercalated organoclays, with a silicate interlayer expansion from 1.2 to 5.2 and 9.2 nm, respectively, are suitable for embedding FeNPs. The presence of POP organics in layered structure created the space for intercalating with FeNPs of 2-4 nm in diameter, observed by transmission electronic microscope. The synthesized nanohybrids of POP4000/MMT-FeNP was composed of 17% iron oxide and 51 wt % POP within the silicate basal spacing of 5.0 nm. In contrast, the lower molecular weight of POP2000 intercalated MMT failed to encapsulate FeNPs in a significant amount, but resulting a "crowding-out effect" that caused the silicate interlayer space to shrink from 5.2 to 1.8 nm because of the replacement of the POP salt by Fe(2+)/Fe(3+) ions. The synthesis required the use of high molecular weight POP4000 and low temperatures (<4 degrees C) for a better dispersion in the reaction medium. The presence of POP in the layered silicate facilitated a homogeneous POP/MMT in water, associating with Fe(2+)/Fe(3+) ions and spatially accommodating for the subsequently generated FeNPs. The synthesized nanostructure consisting of POP and FeNP could be used as a pollutant remedy because of its ability to adsorbing crude oil and it is maneuverable under an applied magnetism.

Investigation of the effects of temperature and sludge characteristics on odors and VOC emissions during the drying process of sewage sludge.

PubMed

Ding, Wenjie; Li, Lin; Liu, Junxin

2015-01-01

Sludge drying is a necessary step for sludge disposal. In this study, sludge was collected from two wastewater treatment plants, and dried at different temperatures in the laboratory. The emission of odor and total volatile organic compounds (TVOCs) during the sludge drying process were determined by an online odor monitoring system. The volatile organic compounds (VOCs) in off-gas were analyzed by gas chromatography-mass spectrometry. Results showed that sludge with 30% moisture content could be obtained in 51 minutes under drying temperature 100 °C but only within 27 minutes under 150 °C. Concentration of odor, TVOCs, sulfur-containing compounds (SCCs), and amines were changed with drying temperature and sludge sources. The maximum concentration of odor, TVOCs, SCCs, and amines were 503.13 ppm, 3.01 ppm, 8.15 ppm, and 11.27 ppm, respectively, at drying temperature 100 °C. These values reached 1,250.79, 8.10, 53.51, and 37.80 ppm when sludge dried at 150 °C. Odor concentration had a close relationship with emission of SCCs, amines, and TVOCs. The main VOCs released were benzene series and organic acid. Potential migration of substances in sludge was examined via analysis of off-gas and condensate, aiming to provide scientific data for effective sludge treatment and off-gas control.

Experiment and Optimization for Simultaneous Carbonation of Ca2+ and Mg2+ in A Two-phase System of Insoluble Diisobutylamine and Aqueous Solution

NASA Astrophysics Data System (ADS)

Wang, Wenlong; Wang, Man; Liu, Xin; Wang, Peng; Xi, Zhenqian

2015-06-01

An optimized approach of CO2 fixation in Ca2+/Mg2+-rich aqueous solutions using insoluble amine as an enhancing medium was reported. Apparent basicity was verified to be an effective indicator for the selection and optimization of organic amine systems and finally the diisobutylamine + n-octanol system was selected to enhance the carbonation reactions of CO2 in an artificial Ca2+/Mg2+-rich solution. In our experiments, when the volume ratio of insoluble organic phase to aqueous one was 2:1 and the reaction temperature was 28 °C, 92% of Ca2+ and 80% of Mg2+ could be converted to calcium and magnesium carbonate precipitates within 5 min of reaction with the bubbling-in of CO2. The organic amine system could be regenerated by using carbide slag as the regeneration agent and could still show attractive enhancement performances after 7 rounds of carbonation-regeneration experiments. In this way, the CO2 capture and sequestration was realized within one single process, with value-added Ca/Mg carbonates being the byproducts. In view of the vast availability of Ca2+/Mg2+-rich aqueous solutions and the feasible technical coordination with desalination industry, this novel process may have a good application potential in the future.

Probes for Narcotic Receptor Mediated Phenomena. 39. Enantiomeric N-Substituted Benzofuro[2,3-c]pyridin-6-ols: Synthesis and Topological Relationship to Oxide-Bridged Phenylmorphans

DTIC Science & Technology

2009-01-01

ray crystallographic analysis of the salt (-)-10 3R-(-)- mandelate (Figure 2). N-Alkylation of the secondary amine 4aR,9aS-9 or 4aS,9aR-10 (Scheme 3... rmsd ) between the heavy atoms of both the dihydrofuran and the piperidine rings. Conformer B1 is epimeric to A and was obtained by nitrogen inversion... rmsd value of the fitting is 0.13, 0.12, and 0.07 Å. The dihydrofuran ring of conformer C overlaps well with that of the para-d isomer that is known to

Anti-cancer agents based on 4-(hetero)Ary1-1,2,5-oxadiazol-3-yl Amino derivatives and a method of making

DOEpatents

Gakh, Andrei A.; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A.; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V.

2013-01-29

The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. ##STR00001## In particular, the invention relates N-substituted derivatives of 4-(hetero)aryl-1,2,5-oxadiazol-3-yl amines having the structural Formula (I) and (II), stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. Meaning of R1 and R2 in the Formula (I) and (II) are defined in claim 1. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

Synthesis, absolute configuration and antimuscarinic activity of the enantiomers of [1-(2,2-diphenyl-[1,3]dioxolan-4-yl)-ethyl]-dimethyl-amine.

PubMed

Gulini, U; Angeli, P; Marucci, G; Buccioni, M; Giardinà, D; Antolini, L; Franchini, S; Sorbi, C; Brasili, L

2001-01-22

Methylation of the carbon atom C of compound 1, a potent and not selective muscarinic antagonist, was carried out. The resulting diastereomers were separated and the corresponding racemate further resolved to give four enantiomers, which were tested both as hydrogen oxalate and methiodide salts. The pharmacological results obtained at M1, M2 and M3 muscarinic receptor subtypes, show that methylation at C1, depending on the stereochemistry, increases antagonist potency, having thus the same effect of nitrogen quaternization. These results may well lead to the development of new potent antimuscarinic drugs lacking a cationic head.

In vitro permeation of diclofenac salts from lyotropic liquid crystalline systems.

PubMed

Yariv, Doron; Efrat, Rivka; Libster, Dima; Aserin, Abraham; Garti, Nissim

2010-07-01

In this paper we examined feasible correlations between the structure of different lyotropic mesophases and transdermal administration of three diclofenac derivatives with varying degrees of kosmotropic or chaotropic properties, solubilized within the mesophases. It was found that the most chaotropic derivative of diclofenac diethyl amine (DEA-DFC) interacted with the polar heads of glycerol monooleate (GMO), thus expanding the water-lipid interface of the lamellar and cubic mesophases. This effect was detected by an increase in the lattice parameter of both mesophases, enhanced elastic properties, and increased solid-like response of the systems in the presence of DEA. Potassium diclofenac (K-DFC), a less chaotropic salt, had less pronounced effect on the structural features of the mesophases. Kosmotropic Na+ salt (Na-DFC) had only minor influence on both lamellar and cubic structures. The locus of solubilization of the molecules with the host mesophases was correlated with their delivery. It was suggested that transdermal delivery of kosmotropic Na-DFC was accelerated by the aqueous phase and less constrained by the interaction with monoglyceride. On the other hand, the chaotropic cations (K+ and DEA+), presumably entrapped in the water-lipid interface, interacted with monoglyceride headgroups, which is likely to be the key cause for their sustained administration. 2010 Elsevier B.V. All rights reserved.

Ligand-modulated interactions between charged monolayer-protected Au144 (SR)60 gold nanoparticles in physiological saline

NASA Astrophysics Data System (ADS)

Villarreal, Oscar; Chen, Liao; Whetten, Robert; Yacaman, Miguel

2015-03-01

We studied the interactions of functionalized Au144 nanoparticles (NPs) in a near-physiological environment through all-atom molecular dynamics simulations. The AuNPs were coated with a homogeneous selection of 60 thiolates: 11-mercapto-1-undecanesulfonate, 5-mercapto-1-pentanesulfonate, 5-mercapto-1-pentane-amine, 4-mercapto-benzoate or 4-mercapto-benzamide. These ligands were selected to elucidate how the aggregation behavior depends on the ligands' sign of charge, length, and flexibility. Simulating the dynamics of a pair of identical AuNPs in a cell of saline of 150 mM NaCl in addition to 120 Na+/Cl- counter-ions, we computed the aggregation affinities from the potential of mean force as a function of the pair separation. We found that NPs coated with negatively charged, short ligands have the strongest affinities mediated by multiple Na+ counter-ions residing on a plane in-between the pair and forming ``salt bridges'' to both NPs. Positively charged NPs have weaker affinities, as Cl counter-ions form fewer and weaker salt bridges. The longer ligands' large fluctuations disfavor the forming of salt bridges, enable hydrophobic contact between the exposed hydrocarbon chains and interact at greater separations due to the fact that the screening effect is rather incomplete. Supported by the CONACYT, NIH, NSF and TACC.

Synthesis and application of a triazene-ferrocene modifier for immobilization and characterization of oligonucleotides at electrodes.

PubMed

Hansen, Majken N; Farjami, Elaheh; Kristiansen, Martin; Clima, Lilia; Pedersen, Steen Uttrup; Daasbjerg, Kim; Ferapontova, Elena E; Gothelf, Kurt V

2010-04-16

A new DNA modifier containing triazene, ferrocene, and activated ester functionalities was synthesized and applied for electrochemical grafting and characterization of DNA at glassy carbon (GC) and gold electrodes. The modifier was synthesized from ferrocenecarboxylic acid by attaching a phenyltriazene derivative to one of the ferrocene Cp rings, while the other Cp ring containing the carboxylic acid was converted to an activated ester. The modifier was conjugated to an amine-modified DNA sequence. For immobilization of the conjugate at Au or GC electrodes, the triazene was activated by dimethyl sulfate for release of the diazonium salt. The salt was reductively converted to the aryl radical which was readily immobilized at the surface. DNA grafted onto electrodes exhibited remarkable hybridization properties, as detected through a reversible shift in the redox potential of the Fc redox label upon repeated hybridization/denaturation procedures with a complementary target DNA sequence. By using a methylene blue (MB) labeled target DNA sequence the hybridization could also be followed through the MB redox potential. Electrochemical studies demonstrated that grafting through the triazene modifier can successfully compete with existing protocols for DNA immobilization through the commonly used alkanethiol linkers and diazonium salts. Furthermore, the triazene modifier provides a practical one-step immobilization procedure.

Spontaneous Aryldiazonium Film Formation on 440C Stainless Steel in Nonaqueous Environments

DOE PAGES

Small, Leo J.; Hibbs, Michael R.; Wheeler, David R.

2014-11-07

The ability of three aryldiazonium salts to spontaneously assemble onto the surface of type 440C stainless steel is investigated in acetonitrile and the model hydraulic fluids tributyl phosphate and hexamethyldisiloxane. Competition between native oxide growth and organic film growth at different diazonium salt concentrations is monitored by electrochemical impedance spectroscopy. At 1 mM diazonium salt, 70% of total assembly is complete within 10 minutes, though total surface coverage by organics is limited to ≈ 0.15 monolayers. X-ray photoelectron spectroscopy confirms preferential bonding of organic molecules to iron over chromium, and adsorption of BF - 4 onto the surface. Secondary ionmore » mass spectroscopy reveals the ability of these films to self-heal when mechanically removed or damaged. Aging the diazonium salts in these nonaqueous environments demonstrates that up to 90% of the original diazonium salt concentration remains after 21 days at room temperature, while increasing the temperature beyond 50 °C results complete decomposition within 24 hours, regardless of solvent-salt combination.« less

Enhancing non-refractory aerosol apportionment from an urban industrial site through receptor modeling of complete high time-resolution aerosol mass spectra

NASA Astrophysics Data System (ADS)

McGuire, M. L.; Chang, R. Y.-W.; Slowik, J. G.; Jeong, C.-H.; Healy, R. M.; Lu, G.; Mihele, C.; Abbatt, J. P. D.; Brook, J. R.; Evans, G. J.

2014-08-01

Receptor modeling was performed on quadrupole unit mass resolution aerosol mass spectrometer (Q-AMS) sub-micron particulate matter (PM) chemical speciation measurements from Windsor, Ontario, an industrial city situated across the Detroit River from Detroit, Michigan. Aerosol and trace gas measurements were collected on board Environment Canada's Canadian Regional and Urban Investigation System for Environmental Research (CRUISER) mobile laboratory. Positive matrix factorization (PMF) was performed on the AMS full particle-phase mass spectrum (PMFFull MS) encompassing both organic and inorganic components. This approach compared to the more common method of analyzing only the organic mass spectra (PMFOrg MS). PMF of the full mass spectrum revealed that variability in the non-refractory sub-micron aerosol concentration and composition was best explained by six factors: an amine-containing factor (Amine); an ammonium sulfate- and oxygenated organic aerosol-containing factor (Sulfate-OA); an ammonium nitrate- and oxygenated organic aerosol-containing factor (Nitrate-OA); an ammonium chloride-containing factor (Chloride); a hydrocarbon-like organic aerosol (HOA) factor; and a moderately oxygenated organic aerosol factor (OOA). PMF of the organic mass spectrum revealed three factors of similar composition to some of those revealed through PMFFull MS: Amine, HOA and OOA. Including both the inorganic and organic mass proved to be a beneficial approach to analyzing the unit mass resolution AMS data for several reasons. First, it provided a method for potentially calculating more accurate sub-micron PM mass concentrations, particularly when unusual factors are present, in this case the Amine factor. As this method does not rely on a priori knowledge of chemical species, it circumvents the need for any adjustments to the traditional AMS species fragmentation patterns to account for atypical species, and can thus lead to more complete factor profiles. It is expected that this method would be even more useful for HR-ToF-AMS data, due to the ability to understand better the chemical nature of atypical factors from high-resolution mass spectra. Second, utilizing PMF to extract factors containing inorganic species allowed for the determination of the extent of neutralization, which could have implications for aerosol parameterization. Third, subtler differences in organic aerosol components were resolved through the incorporation of inorganic mass into the PMF matrix. The additional temporal features provided by the inorganic aerosol components allowed for the resolution of more types of oxygenated organic aerosol than could be reliably resolved from PMF of organics alone. Comparison of findings from the PMFFull MS and PMFOrg MS methods showed that for the Windsor airshed, the PMFFull MS method enabled additional conclusions to be drawn in terms of aerosol sources and chemical processes. While performing PMFOrg MS can provide important distinctions between types of organic aerosol, it is shown that including inorganic species in the PMF analysis can permit further apportionment of organics for unit mass resolution AMS mass spectra.

Enhancing non-refractory aerosol apportionment from an urban industrial site through receptor modelling of complete high time-resolution aerosol mass spectra

NASA Astrophysics Data System (ADS)

McGuire, M. L.; Chang, R. Y.-W.; Slowik, J. G.; Jeong, C.-H.; Healy, R. M.; Lu, G.; Mihele, C.; Abbatt, J. P. D.; Brook, J. R.; Evans, G. J.

2014-02-01

Receptor modelling was performed on quadrupole unit mass resolution aerosol mass spectrometer (Q-AMS) sub-micron particulate matter (PM) chemical speciation measurements from Windsor, Ontario, an industrial city situated across the Detroit River from Detroit, Michigan. Aerosol and trace gas measurements were collected on board Environment Canada's CRUISER mobile laboratory. Positive matrix factorization (PMF) was performed on the AMS full particle-phase mass spectrum (PMFFull MS) encompassing both organic and inorganic components. This approach was compared to the more common method of analysing only the organic mass spectra (PMFOrg MS). PMF of the full mass spectrum revealed that variability in the non-refractory sub-micron aerosol concentration and composition was best explained by six factors: an amine-containing factor (Amine); an ammonium sulphate and oxygenated organic aerosol containing factor (Sulphate-OA); an ammonium nitrate and oxygenated organic aerosol containing factor (Nitrate-OA); an ammonium chloride containing factor (Chloride); a hydrocarbon-like organic aerosol (HOA) factor; and a moderately oxygenated organic aerosol factor (OOA). PMF of the organic mass spectrum revealed three factors of similar composition to some of those revealed through PMFFull MS: Amine, HOA and OOA. Including both the inorganic and organic mass proved to be a beneficial approach to analysing the unit mass resolution AMS data for several reasons. First, it provided a method for potentially calculating more accurate sub-micron PM mass concentrations, particularly when unusual factors are present, in this case, an Amine factor. As this method does not rely on a priori knowledge of chemical species, it circumvents the need for any adjustments to the traditional AMS species fragmentation patterns to account for atypical species, and can thus lead to more complete factor profiles. It is expected that this method would be even more useful for HR-ToF-AMS data, due to the ability to better understand the chemical nature of atypical factors from high resolution mass spectra. Second, utilizing PMF to extract factors containing inorganic species allowed for the determination of extent of neutralization, which could have implications for aerosol parameterization. Third, subtler differences in organic aerosol components were resolved through the incorporation of inorganic mass into the PMF matrix. The additional temporal features provided by the inorganic aerosol components allowed for the resolution of more types of oxygenated organic aerosol than could be reliably resolved from PMF of organics alone. Comparison of findings from the PMFFull MS and PMFOrg MS methods showed that for the Windsor airshed, the PMFFull MS method enabled additional conclusions to be drawn in terms of aerosol sources and chemical processes. While performing PMFOrg MS can provide important distinctions between types of organic aerosol, it is shown that including inorganic species in the PMF analysis can permit further apportionment of organics for unit mass resolution AMS mass spectra.

Self-assembling Gold Nanoparticle Monolayers in a Three-phase System - Overcoming Ligand Size Limitations

NASA Astrophysics Data System (ADS)

Yang, Guang; Nanda, Jagjit; Wang, Boya; Chen, Gang; Hallinan, Daniel T., Jr.

An effective self-assembly technique was developed to prepare centimeter-scale monolayer gold nanoparticle (Au NP) films of long-range order with hydrophobic ligands. Aqueous Au NPs were entrapped in the organic/aqueous interface where the Au NP surface was in situ modified with different types of amine ligands, including amine-terminated polystyrene. The Au NPs then spontaneously relocated to the air/water interface to form an NP monolayer. The spontaneous formation of an Au NP film at the organic/water interface was due to the minimization of the system Helmholtz free energy. Self-assembled Au NP films has a hexagonal close packed structure. The interparticle spacing was dictated by the amine ligand length. Thus-assembled Au NP monolayers exhibit tunable surface plasma resonance and excellent spacial homogeneity of surface-enhanced Raman-scattering. The ``air/water/oil'' self-assembly method developed in this study not only benefits the fundamental understanding of NP ligand conformations, but is also promising to scale up the manufacture of plasmonic nanoparticle devices with precisely designed optical properties. This study was financially supported by start-up funding supplied by the Florida State University and the FAMU-FSU College of Engineering.

Ion Pair Formation between Tertiary Aliphatic Amines and Perchlorate in the Biphasic Water/Dichloromethane System.

PubMed

Badocco, Denis; Di Marco, Valerio; Venzo, Alfonso; Frasconi, Marco; Frezzato, Diego; Pastore, Paolo

2017-10-12

The ability of aliphatic amines (AAs), namely, tripropylamine (TPrA), trisobutylamine (TisoBuA), and tributylamine (TBuA), to form ion pairs with perchlorate anion (ClO 4 - ) in biphasic aqueous/dichloromethane (CH 2 Cl 2 ) mixtures containing ClO 4 - 0.1 M has been demonstrated by GC with flame ionization (FID) and mass detectors (MS) and by NMR measurements. The extraction efficiency of the AAs to the organic phase was modeled by equations that were used to fit the experimental GC data, allowing us to determine values for K P (partition constant of the free AA), K IP (formation constant of the ion pair), and K P IP (partition constant of the ion pair) for TPrA, TisoBuA, and TBuA at 25 °C. Ion pairs were shown to form in CH 2 Cl 2 also when ClO 4 - is replaced by other inorganic anions, like NO 3 - , ClO 3 - , Cl - , H 2 PO 4 - , and IO 3 - . No ion pairs formed when CH 2 Cl 2 was replaced by n-hexane, suggesting that aliphatic amine ion pairs can form in polar organic solvents but not in nonpolar ones.

Copper sulfate-pentahydrate-1,10-phenanthroline catalyzed amidations of alkynyl bromides. Synthesis of heteroaromatic amine substituted ynamides.

PubMed

Zhang, Yanshi; Hsung, Richard P; Tracey, Michael R; Kurtz, Kimberly C M; Vera, Eymi L

2004-04-01

A practical cross-coupling of amides with alkynyl bromides using catalytic CuSO(4).5H(2)O and 1,10-phenanthroline is described here. This catalytic protocol is more environmentally friendly than the use of CuCN or copper halides and provides a general entry for syntheses of ynamides including various new sulfonyl and heteroaromatic amine substituted ynamides. Given the interest in ynamides, this N-alkynylation of amides should be significant for the future of ynamides in organic synthesis.