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  • 51. Bratt, Katarina
    et al.
    Sunnerheim, Kerstin
    Bryngelsson, Susanne
    Fagerlund, Amelie
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Engman, Lars
    Andersson, Rolf E
    Dimberg, Lena H
    Avenanthramides in Oats (Avena Sativa L.) and Structure-Activity Relationships2003Inngår i: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 51, nr 3, s. 594-600Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Eight avenanthramides, amides of anthranilic acid (1) and 5-hydroxyanthranilic acid (2), respectively, and the four cinnamic acids p-coumaric (p), caffeic (c), ferulic (f), and sinapic (s) acid, were synthesized for identification in oat extracts and for structure−antioxidant activity studies. Three compounds (2p, 2c, and 2f) were found in oat extracts. As assessed by the reactivity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH), all avenanthramides except 1p showed activity. Initially, the antioxidant activity of the avenanthramides decreased in a similar order as for the corresponding cinnamic acids, that is: sinapic > caffeic > ferulic > p-coumaric acid. The avenanthramides derived from 2 were usually slightly more active than those derived from 1. All avenanthramides inhibited azo-initiated peroxidation of linoleic acid. 1c and 1s were initially the most effective compounds. The relative order of antioxidant activities was slightly different for the DPPH and the linoleic acid assays run in methanol and chlorobenzene, respectively.

  • 52.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Development of highly enantioselective organocatalyzed transformations2011Doktoravhandling, med artikler (Annet vitenskapelig)
  • 53.
    Breistein, Palle
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Johansson, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Lin, S.
    Deiana, Luca
    Sun, J.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    One-step catalytic enantioselective 5-hydroxy-α-quaternary proline synthesis: An asymmetric entry to highly functionalized α-quaternary proline derivativesManuskript (preprint) (Annet vitenskapelig)
  • 54.
    Breistein, Palle
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Karlsson, Staffan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Hedenström, Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Chiral pyrrolidinium salts as organocatalysts in stereoselective 1,4-conjugate addition of N-methylpyrrole to cyclopent-1-ene carbaldehyde2006Inngår i: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 17, nr 1, s. 107-111Artikkel i tidsskrift (Fagfellevurdert)
  • 55.
    Bydén Sjöbom, Malin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Dependence of Alkyl Chain Asymmetry on the Phase Equilibria of Three Catanionic Surfactant Mixtures Containing Dodecyltrimethylammonium Chloride-Sodium Alkylcarboxylate-Water2002Inngår i: Langmuir, ISSN 0743-7463, Vol. 18, nr 22, s. 8309-8317Artikkel i tidsskrift (Fagfellevurdert)
  • 56.
    Bydén Sjöbom, Malin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Lindström, Birger
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    BinaBinary Phase Equilibria and Structure of the Two α-Methyl-Substituted Surfactants Sodium (R)-2-Methyldecanoate and Racemic Sodium 2-Methyldecanoate ry Phase Exuilibria and Structure of the Chiral α-Methylsubstituted Surfactants Sodium (R)-2-Methyldecanoate and Racemic Sodium 2-Methyldecanoate1999Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 15, nr 8, s. 2654-2660Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, we present the binary phase diagrams for the aqueous systems of the alkyldecanoic salts racemic sodium 2-methyldecanoate and sodium (R)-2-methyldecanoate, respectively. Both systems form a micellar solution phase, as well as a normal hexagonal, a cubic, and a lamellar liquid crystalline phase. They also form a very narrow intermediate phase, situated between the hexagonal and cubic liquid crystalline phases. The methods used for characterization were crossed polaroids, polarizing optical microscope and 2H NMR quadrupolar splittings combined with SAXS studies. The cubic phase gave a well-resolved SAXS diffraction pattern, with eight peaks present, which establishes the bicontinuous cubic structure as Ia3d. A significant difference in these two phase diagrams, compared to those of unsubstituted alkanoates with the same chain length, is the very low Krafft boundary.

  • 57.
    Bydén Sjöbom, Malin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Hedenström, Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Binary Phase Equilibria of Three alfa-Methylsubstituted Sodium Alkanoate Surfactant Systems.2003Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, Vol. 257, nr 2, s. 333-336Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work, we continue our study of methyl -substituted surfactants and present the aqueous binary phase diagrams of racemic sodium 2-methyloctanoate, -nonanoate, and -dodecanoate, respectively. All systems have very low Krafft temperatures within the solution phase, between 1 and 4 degreesC. The phase sequences of the two shorter surfactants are very similar to those of the unsubstituted sodium octanoate, although with somewhat different range of existence for the phases formed. The sodium 2-methyldodecanoate system is different from the unsubstituted sodium dodecanoate system, as the former seems to lack a hexagonal phase. The surfactant systems were delineated using H-2 NMR splittings and crossed polarizers, and combined with SAXS for determination of phase structure. 

  • 58.
    Bydén Sjöbom, Malin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Marques, Eduardo
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Khan, Ali
    Phase Equilibria of the Mixed Didodecyldimethylammonium Bromide-Taurodeoxycholate-Water System with a Large Solution Region.2005Inngår i: Colloids and Surfaces, ISSN 0166-6622, E-ISSN 1873-4340, Vol. 269, nr 1-3, s. 87-95Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The phase behavior over the entire concentration range for the system didodecyldimethylammonium bromide (DDAB)-sodium taurodeoxycholate (STDC)-water, at 25 degrees C, has been investigated, with emphasis on the DDAB-rich part. Polarizing microscopy, SAXS, H-2 NMR and H-1 self-diffusion NMR have been used in combination as probing techniques for phase behavior and microstructure. The system forms four major phases, all deriving from the respective binary surfactant systems. The two lamellar phases originating from the binary DDAB-water axis (D-I and D-II, at 3-30 and 83-91 wt.% DDAB, respectively) are only able to incorporate small amounts of STDC. The D-II phase solubilizes a comparatively higher amount of bile salt (up to ca. 6 wt.%), while the D, phase takes up less than 0.25 wt.%. From the STDC-water axis, a solution phase and a "hexagonal-like" liquid crystalline phase are derived, at 0-26 and 37-60 wt.% of STDC, respectively. Heterogeneous regions are also indicated on the basis of NMR and SAXS data. The most striking feature is the large extension of the isotropic solution phase, which originates from the water corner and curves toward the DDAB-rich side of the phase diagram. Even though at the upper limit of the solution phase the amount of water is reduced to 10 wt.%, the measured water and DDAB self-diffusion coefficients exclude the possibility of reverse-type structures.

  • 59. Byers, J
    et al.
    Högberg, Hans-Erik
    Unelius, C. R.
    Birgersson, G.
    Löfqvist, J.
    Structure-Activity Studies on Aggregation Pheromone Components of Pithyogenes chalcographus (Coleoptera: Scolytidae): All stereoisomers of Chalcogran and Methyl 2,4-Decadienoate1989Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 15, nr 2, s. 685-695Artikkel i tidsskrift (Fagfellevurdert)
  • 60.
    Bylund, Dan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Chemometric tools for enhanced performance in liquid chromatography-mass spectrometry2001Doktoravhandling, monografi (Annet vitenskapelig)
  • 61.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Bergens, Arne
    Jacobsson, S P.
    Optimisation of chromatographic separations by use of a chromatographic response function, empirical modelling and multivariate analysis1997Inngår i: Chromatographia, ISSN 0009-5893, Vol. 44, nr 1/2, s. 74-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The chiral separation of the drug substance R,S-oxybutynin chloride on a reversed phase HPLC system has been optimised by use of empirical modelling and multivariate analysis. The separation was characterised by a new chromatographic response function developed to modulate both quality of separation and retention time. The study includes a comparison between three different multivariate techniques (multi-layer feed-forward neural networks, multiple linear regression and partial least squares regression) of their capabilities to model the new chromatographic response function and predict its value for new experiments. It was indicated that the most accurate models were achieved with neural networks, although partial least squares regression could also be used to solve the problem since it gives the major directions for the optimal settings of the variables.

  • 62.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Danielsson, Rolf
    Malmquist, Gunnar
    Markides, Karin A
    Chromatographic alignment by warping and dynamic programming as a pre-processing tool for PARAFAC modelling of liquid chromatography-mass spectrometry data2002Inngår i: Journal of Chromatography A, ISSN 0021-9673, Vol. 961, nr 2, s. 237-244Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Solutes analysed with LC–MS are characterised by their retention times and mass spectra, and quantified by the intensities measured. This highly selective information can be extracted by multiway modelling. However, for full use and interpretability it is necessary that the assumptions made for the model are valid. For PARAFAC modelling, the assumption is a trilinear data structure. With LC–MS, several factors, e.g. non-linear detector response and ionisation suppression may introduce deviations from trilinearity. The single largest problem, however, is the retention time shifts not related to the true sample variations. In this paper, a time warping algorithm for alignment of LC–MS data in the chromatographic direction has been examined. Several refinements have been implemented and the features are demonstrated for both simulated and real data. With moderate time shifts present in the data, pre-processing with this algorithm yields approximately trilinear data for which reasonable models can be made.

  • 63.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Danielsson, Rolf
    Markides, Karin E
    Peak purity assessment in liquid chromatography-mass spectrometry2001Inngår i: Journal of Chromatography A,, ISSN 0021-9673, Vol. 915, nr 1/2, s. 43-52Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fixed-size moving window evolving factor analysis and base peak chromatograms have been used for peak purity detection in data generated with LC–MS. The two methods were evaluated with both real and simulated data and were found to be fast and complementary to each other. When a possibly impure peak is detected, it is suggested that further information can be obtained from local principal component analysis modelling and comparative mass chromatogram plots.

  • 64.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Henriksson, Anders E.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Sundsvalls sjukhus.
    Proteomic approaches to identify circulating biomarkers in patients with abdominal aortic aneurysm2015Inngår i: American Journal of Cardiovascular Disease, ISSN 2160-200X, Vol. 5, nr 3, s. 140-145Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Abdominal aortic aneurysm (AAA) is a common condition with high mortality when ruptured. Most clinicians agree that small AAAs are best managed by ultrasonographic surveillance. However, it has been stated in recent reviews that a serum/plasma biomarker that predicts AAA rupture risk would be a powerful tool in stratifying patients with small AAAs. Identification of such circulating biomarkers with traditional hypothesis driven studies has been unsuccessful. In this review we summarize six studies using different proteomic approaches to find new, potential plasma AAA biomarker candidates. In conclusion, by using proteomic approaches novel potential plasma biomarkers for AAA have been identified.

  • 65.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Norström, Sara
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Essén, Sofia
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Lundström, Ulla
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Analysis of low molecular mass organic acids in natural waters by ion exclusion chromatography tandem mass spectrometry2007Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1176, nr 1-2, s. 89-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A sensitive and selective method for the analysis of aliphatic low molecular mass organic acids (LMMOAs) in natural waters is presented. The method is based on separation with ion exclusion chromatography and detection with electrospray ionization tandem mass spectrometry (LC-MS/MS). The extra selectivity gained by applying MS/MS allows for a minimum of sample preparation and the use of a sub-optimal mobile phase regarding chromatographic resolution. Instead the mobile phase, comprising aqueous formic acid With methanol as organic modifier, was mainly optimized for maximum sensitivity and long term MS stability. Detection limits for malonic, fumaric, maleic, succinic, citraconic, glutaric, malic, alpha-ketoglutaric, tartaric, shikimic, trans-aconitic, cis-aconitic, isocitric and citric acid were in the range 1-50 nM, while the detection limits for pyruvic, oxalic and lactic acid were around 250 nM for an injection volume of 100 mu L. Due to their metal-chelating properties, these LMMOAs are all considered to affect the bioavailability of metals and to be involved in soil forming processes. It is thus of interest to be able to monitor their presence in natural waters, and the method developed within this work was successfully applied for the analysis of LMMOAs in soil solution and stream water samples.

  • 66.
    Bylund, Dan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Samskog, J
    Jacobsson, S.P.
    Markides, K.E.
    Classification of lactate dehydrogenase of different origin by liquid chromatography-mass spectrometry and multivariate analysis2003Inngår i: Journal of the American Society for Mass Spectrometry, ISSN 1044-0305, E-ISSN 1879-1123, Vol. 14, nr 3, s. 236-240Artikkel i tidsskrift (Fagfellevurdert)
  • 67. Bäckström, P
    et al.
    Bergström, G
    Björkling, F
    Hui-Zhu, H
    Högberg, Hans-Erik
    Jacobsson, Ulla
    Guo-Qiang, L
    Löfqvist, J
    Norin, Torbjörn
    Wassgren, A.-B.
    Structures, Absolute Configurations and Syntheses of the Volatile Signals from three Sympatric Ant-Lion Species, Euroleon nostras Grocus bore and Myrmeleon formicarius (Neuroptera: Myrmeleontidae).1989Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, Vol. 15, nr 1, s. 61-80Artikkel i tidsskrift (Fagfellevurdert)
  • 68. Bäckström, Peter
    et al.
    Björkling, Fredrik
    Högberg, Hans-Erik
    Norin, Torbjörn
    New three-step synthesis of racemic and optically active ipsdienol from myrcene1983Inngår i: Acta Chemica Scandinavica Ser. B: Organic Chemistry and Biochemistry, ISSN 0302-4369, Vol. B37, nr 1, s. 1-5Artikkel i tidsskrift (Fagfellevurdert)
  • 69. Bäckström, Petre
    et al.
    Björkling, Fredrik
    Högberg, Hans-Erik
    Norin, Torbjörn
    Cross-coupling of vinyl cuprates and allylic halides and synthesis of the Comstock Mealybug pheromone via photooxidation 2,6-dimethyl-2,5-heptadiene.1984Inngår i: Acta Chemica Scandinavica Ser. B - Organic chemistry and Biochemistry, ISSN 0302-4369, Vol. B38, nr 9, s. 779-782Artikkel i tidsskrift (Fagfellevurdert)
  • 70.
    Bång, Joakim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). Both pheromones and allelochemicals can be used as environmentally friendly pest management. Many semiochemicals, i.e. behaviour modifying chemicals, consist of pure or well-defined mixtures of stereoisomers, where some of the other stereoisomers can be repellent. It is therefore important to be able to separate them to produce a synthetic pheromone in a mixture that is attractive.

    Pine sawflies are a family of insects that in some cases can be severe defoliators of conifer trees. Diprion pini, Diprion similis and Neodiprion sertifer are severe pests for these trees and have got the most attention in pine sawfly pheromone studies. The pheromone precursors are stored in the female body as long-chain secondary alcohols, which, when released, are esterified to acetates or propionates. The alcohols are chiral, and normally one of the stereoisomer is the main pheromone component, sometimes possible together with other stereoisomers as essential minor components.

    Bicyclus is a genus of African butterflies, and especially Bicyclus anynana has become a popular model for the study of life history evolution, morphology, mating choice and genetics. The wing pattern of Bicyclus differs depending on the season, with large eyespots during the rain-season and small or absent spots during the dry season.

     Euglossa is one of the genera among the orchid bees in the Neotropics that does not produce its own pheromone. Instead, the males collect fragrances from orchids and other sources and store them in a pocket in their hind legs. Both Bicyclus and Euglossa use semiochemicals similar to pine sawflies, and thus can be analysed by the same methods.

    Pheromones and other semiochemicals in insects are often present in low amounts in a complex matrix, and purification of the sample before chemical analysis is often required. A common method is gradient elution on a solid phase silica column. Separation of stereoisomers can be achieved either by using a column with a chiral stationary phase (CSP) or with pre-column derivatisation using a column with an achiral stationary phase (ASP) or a combination of both, with mass detection as the dominant detection method. The purpose of this work has been to improve the purification method, find suitable methods to separate the stereoisomers of secondary alcohols, and to apply this on extracts of insects.

    By selecting the right fractions to collect during gradient elution the purification method was optimised. To reduce plasticizer contamination from ordinary columns, solid phase columns of Teflon or glass were used. For pre-column derivatisation of different chiral alcohols various acid chlorides were tested. For the pine sawfly pheromone precursors enantiopure (2S)-2-acetoxypropionyl chloride was the best choice. To separate some of the stereoisomers achiral 2-naphthoyl chloride was used. For derivatisation of 6,10,14-trimethylpentadecan-2-ol (R)-trans-chrysanthemoyl chloride was the best choice. The derivatised alcohols were separated on different columns, both chiral and non-chiral. Varian FactorFour VF-23ms was chosen as a general-purpose column, the Agilent HP-88 column was the best column with an ASP of those tested, and the Chiraldex B-PA column (CSP) was the only one that could separate all eight stereoisomers of derivatised 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol.

    To determine the stereoisomeric purity of standard solutions used in field experiments and extracts of different species of insects the optimised methods were applied. For extracts from B. anynana, Euglossa and Neodiprion lecontei this work describe the first determination of the stereochemistry of some of their semiochemicals.

    For the determination of the stereochemistry of chiral semiochemicals the methods for purification and separation presented herein have shown to be of great value. The results will hopefully contribute to a better understanding of the communication among insects, and ultimately to a more environmentally friendly pest control.

  • 71.
    Bång, Joakim
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Hedenström, Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Anderbrant, Olle
    Lund Univ, Dept Biol, Lund, Sweden.
    Stereoisomeric separation of derivatized 2-alkanols using gas chromatography – mass spectrometry: Sex pheromone precursors found in pine sawfly species2012Inngår i: Analytical Letters, ISSN 0003-2719, E-ISSN 1532-236X, Vol. 45, nr 9, s. 1016-1027Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stereoisomers of long-chain secondary alcohols are used as sex pheromone precursors among pine sawflies, which can be severe pest to conifers. To use the pheromone in environmentally friendly pest managements, methods are needed that can determine the exact stereochemistry of the precursor alcohols. Combinations of 11 acid chloride derivatives and 10 GC columns were evaluated for separation of the stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol, and 3,7-dimethylpentadecan-2-ol. Derivatisation with (2S)-2-acetoxypropionyl chloride in combination with the Chiraldex B-PA column separated all eight stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol and 3,7-dimethyltridecan-2-ol. A combination of two different derivatisation methods was needed to separate all stereoisomers of the longer chained alcohols, 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol. An extract of the pine sawfly Neodiprion lecontei was also analysed, and the stereochemistry of the sex pheromone alcohol prcursor was determined to be (2S,3S,7S)-3,7-dimethylpentadecan-2-ol, at an amount of about 7 ng/female. This paper presents the first GC-MS-separation of all eight stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol and 3,7-dimethyltridecan-2-ol in a single analytical run, and also the first determination of the stereochemistry of the sex pheromone precursor of N. lecontei.

  • 72.
    Bång, Joakim
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Hedenström, Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Sjödin, Kristina
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Purification, Stereoisomeric Analysis and Quantification of Sex Pheromone Precursors in Female Whole Body Extracts from Pine Sawfly Species2011Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 37, nr 1, s. 125-133Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A GC-MS method to analyze the stereoisomeric composition of chiral secondary alcohols found in whole body extracts of pine sawfly females was developed. The tested alcohols were derivatized with optically pure (S)-2-acetoxypropionyl chloride prior to GC-MS analysis. Baseline separation was obtained for all sixteen stereoisomers of 3,7,9-trimethyltridecan-2-ol and for the four 3-methylpentadecan-2-ol stereoisomers. For 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol baseline separation was obtained for 6 of the possible 8 stereoisomers. When a mixture of 16 stereoisomers of 3,7,11-trimethyltridecan-2-ol was tested, baseline separation of 7 peaks out of 16 possible was obtained. The investigated alcohols are pheromone precursors for some pine sawfly species that are severe defoliators of pine. Females from several Diprion, Neodiprion, Macrodiprion, Microdiprion, and Gilpinia species emit esters of such secondary alcohols as sex pheromones that attract males for mating. To quantify the small amounts of the precursor alcohol and its stereoisomeric composition found in whole body extracts from female pine sawflies, a purification method was optimized. An extract of 20 females of D. pini contained about 8 ng of (2 S,3 R,7 R)-3,7-dimethyltridecan-2-ol per female, and three extracts of 18, 20, and 90 females of N. sertifer contained between 5 and 13 ng of (2 S,3 S,7 S)-3,7-dimethylpentadecan-2-ol per female.

  • 73.
    Bökman, C.F.
    et al.
    Clinical Chemistry Laboratory, Falun Central Hospital, Falun.
    Bylund, Dan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Markides, K.E.
    Department of Analytical Chemistry, Uppsala University, Uppsala.
    Sjöberg, P.J.R.
    Department of Analytical Chemistry, Uppsala University, Uppsala .
    Relating chromatographic retention and electrophoretic mobility to the ion distribution within electrosprayed droplets2006Inngår i: Journal of the American Society for Mass Spectrometry, ISSN 1044-0305, E-ISSN 1879-1123, Vol. 17, nr 3, s. 318-324Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ions that are observed in a mass spectrum obtained with electrospray mass spectrometry can be assumed to originate preferentially from ions that have a high distribution to the surface of the charged droplets. In this study, a relation between chromatographic retention and electrophoretic mobility to the ion distribution (derived from measured signal intensities in mass spectra and electrospray current) within electrosprayed droplets for a series of tetraalkylammonium ions, ranging from tetramethyl to tetrapentyl, is presented. Chromatographic retention in a reversed-phase system was taken as a measure of the analyte's surface activity, which was found to have a large influence on the ion distribution within electrosprayed droplets. In addition, different transport mechanisms such as electrophoretic migration and diffusion can influence the surface partitioning coefficient. The viscosity of the solvent system is affected by the methanol content and will influence both diffusion and ion mobility. However, as diffusion and ion mobility are proportional to each other, we have, in this study, chosen to focus on the ion mobility parameter. It was found that the influence of ion mobility relative to surface activity on the droplet surface partitioning of analyte ions decreases with increasing methanol content. This effect is most probably coupled to the decrease in droplet size caused by the decreased surface tension at increasing methanol content. The same observation was made upon increasing the ionic strength of the solvent system, which is also known to give rise to a decreased initial droplet size. The observed effect of ionic strength on the droplet surface partitioning of analyte ions could also be explained by the fact that at higher ionic strength, a larger number of ions are initially closer to the droplet surface and, thus, the contribution of ionic transport from the bulk liquid to the liquid/air surface interface (jet and droplet surface), attributable to migration or diffusion will decrease.

  • 74. Carlsson, Håkan
    et al.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Persson, Gerd
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Lindström, Birger
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik, fysik och matematik.
    Competition Between Monovalent and Divalent Counterions in a Surfactant / Water System1996Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 180, nr 2, s. 598-604Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Competition between mono- and divalent ions in the association of counterions to the headgroups of amphiphiles was studied in one surfactant system with organic counterions (piperidine+/piperazine2+octanesulfonate) and one with inorganic counterions (Na+/Ca2+octyl sulfate). By conductivity and13C NMR chemical shift measurements the critical micelle concentration (CMC) was found to decrease drastically when small amounts of divalent counterions were present in the system. Self-diffusion coefficients of surfactant ions and organic counterions were measured in the micellar phase by the Fourier transform pulsed-gradient spin-echo (FT-PGSE) NMR method. The degree of counterion binding in the micellar system with piperidine+/piperazine2+counterions was obtained from FT-PGSE NMR measurements. It was observed that the divalent counterions were more strongly bound than the monovalent counterions. The experimental results were compared with theoretical Poisson–Boltzmann calculations. The cell model was used to study the electrostatic effects. Good agreement between electrostatic theory and experiment was observed; however, an attractive force exists between the monovalent piperidine counterions and the micelle, probably because of hydrophobic interactions.

  • 75.
    Clancy, Gunilla
    et al.
    Chalmers University of Technology.
    Fröling, Morgan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för ekoteknik och hållbart byggande.
    Svanström, Magdalena
    Chalmers University of Technology.
    Changing from petroleum to wood-based materials: critical review of how product sustainability characteristics can be assessed and compared2013Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 39, s. 372-385Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This paper reports on a literature survey on available approaches for the assessment of product sustainability, with a specific focus on assessing the replacement of non-renewable petroleum-based materials with renewable wood-based materials in absorbent hygiene products. The results are contrasted to needs in a specific material development project. A diverse number of methods exist that can help in assessing different product sustainability characteristics for parts of or whole product lifecycles. None of the assessment methods found include guidelines for how to make a case-specific interpretation of sustainability and there is a general lack of assessment parameters that can describe considerations in the comparison between the use of wood or petroleum as main raw material. One reason for this is lack of knowledge and/or consensus on how to describe and assess impacts of land and water use, e.g. on ecosystem services, different types of resource depletion and social impacts.

  • 76.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Combined heterogeneous metal/organic catalysts for eco-friendly synthesis2015Inngår i: Pure and Applied Chemistry, ISSN 0033-4545, E-ISSN 1365-3075, Vol. 87, nr 9-10, s. 1011-1019Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The interplay and synergistic cooperation between homogeneous and heterogeneous catalyst systems is of utmost importance in nature. It is also applied in chemical synthesis. Here, it can allow for new reactivity, which is not possible by the employment of a single catalyst, and promote the catalysis of multiple transformations in a one-pot sequence. This could overall lead to novel reactions and the development of sustainable chemistry. In this context, a versatile and broad synergistic strategy for the selective synthesis of valuable molecules with variable complexity and under eco-friendly conditions is disclosed. It is based on integrated heterogeneous metal/organo multiple relay catalysis, which is performed in a single reaction vessel, and allows for the assembly of complex molecules (e.g., heterocycles and carbocycles) with up to three quaternary stereocenters in a highly enantioselective fashion from simple alcohols and air/O-2.

  • 77.
    Cordova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Cihalova, Sylva
    Charles Univ Prague, Fac Sci, Dept Organ & Nucl Chem, Prague 12840, Czech Republic .
    Dziedzic, Pawel
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Vesely, Jan
    Charles Univ Prague, Fac Sci, Dept Organ & Nucl Chem, Prague 12840, Czech Republic .
    Asymmetric Aza-Morita-Baylis-Hillman-type reactions: The highly enantioselective reaction between unmodified α,β-unsaturated aldehydes and N-acyl imines by organo-co-catalysis2011Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, ISSN 1615-4150, Vol. 353, nr 7, s. 1096-1108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The highly enantioselective organo-co-catalytic aza-Morita-Baylis-Hillman (MBH)-type reaction between N-carbamate-protected imines and alpha,beta-unsaturated aldehydes has been developed. The organic co-catalytic system of proline and 1,4-diazabicyclo[2.2.2]octane (DABCO) enables the asymmetricsynthesis of the corresponding N-Boc- and N-Cbz-protected beta-amino-alpha-alkylidene-aldehydes in good to high yields and up to 99% ee. In the case of aza-MBH-type addition of enals to phenylprop-2-ene-1-imines, the co-catalytic reaction exhibits excellent 1,2-selectivity. The organo-co-catalytic aza-MBH-type reaction can also be performed by the direct highly enantioselective addition of alpha,beta-unsaturated aldehydes to bench-stable N-carbamate-protected alpha-amidosulfones to give the corresponding beta-amino-alpha-alkylidene-aldehydes with up to 99% ee. The organo-co-catalytic aza-MBH-type reaction is also an expeditious entry to nearly enantiomerically pure beta-amino-alpha-alkylidene-amino acids and beta-amino-alpha-alkylidene-lactams (99% ee). The mechanism and stereochemistry of the chiral amine and DABCO co-catalyzed aza-MBH-type reaction are also discussed.

  • 78.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Catalytic Asymmetric Conjugate Reactions2010Collection/Antologi (Annet vitenskapelig)
    Abstract [en]

    Information from publisher:

    This unique and long-awaited handbook on this important topic in the hot field of stereoselective organic synthesis covers several types of nucleophiles. Top international authors deal with modern forms of achieving stereoselective conjugate additions based on the use of chiral ligands or asymmetric catalysis, such as P-N ligands, organocatalysis, domino reactions, Lewis acid and base catalysis. There is also a discussion of the employment of enantioselective conjugate addition transformations in total synthesis of important molecules. With its reliable and previously unpublished experimental procedures, this is a true source of high quality information.

  • 79.
    Córdova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Deiana, Luca
    Zhao, Gui-Ling
    Dziedzic, Pawel
    Pirttilä, Kristian
    Lin, Shuangzheng
    TOC-Trends in Organic Chemistry: Selective Catalysis2010Konferansepaper (Annet vitenskapelig)
  • 80.
    Córdova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    R., Rios
    Aziridine Formation: in C-N Bond Formation2012Inngår i: Comprehensive Chirality / [ed] Yamamoto, H.; Carreira, E. Eds, Oxford: Elsevier, 2012Kapittel i bok, del av antologi (Fagfellevurdert)
  • 81.
    Dahlström, Christina
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Sample Preparation Using Argon Ion Beam Milling2013Inngår i: Argon: Production, Characteristics and Applications / [ed] Bogos Nubar Sismanoglu, Homero Santiago Maciel, Marija Radmilovic-Radjenovic, Rodrigo Savio Pessoa (Physics Department, Lab of Optics and Spectroscopy, Lab of Plasmas and Processes and Lab of Mechanics, Heath and Waves, Technological Institute of Aeronaut, Hauppauge, NY: Nova Science Publishers, Inc., 2013, s. 223-240Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Surface and cross section analysis can provide important information on material properties. It has, however, been difficult to characterise the internal structure at a micro scale using cross sections prepared with conventional methods, such as e.g. mechanical grinding and polishing, because these procedures can damage the surface and introduce artefacts. A few years ago, a new precision argon ion beam cross section polisher was shown to be a suitable sample preparation technique for microstructure characterisation. It produces high quality cross sections free from artefacts and distortions. This technique can be used for cross section preparation of a wide variety of materials including composites, metals, ceramics and polymers. Argon ion beam milling can also be used in combination with focused ion beam (FIB) as a final step to remove FIB-damaged layers before nano- and microstructure characterisation in high resolution transmission electron microscopy (HRTEM).

  • 82.
    Dahlström, Christina
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    López Durán, V.
    KTH, Stockholm.
    Keene, S. T.
    Stanford University, Stanford, CA, United States.
    Salleo, A.
    Stanford University, Stanford, CA, United States.
    Norgren, Magnus
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Wågberg, L.
    KTH, Stockholm.
    Ion conductivity through TEMPO-mediated oxidated and periodate oxidated cellulose membranes2020Inngår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 233, artikkel-id 115829Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cellulose in different forms is increasingly used due to sustainability aspects. Even though cellulose itself is an isolating material, it might affect ion transport in electronic applications. This effect is important to understand for instance in the design of cellulose-based supercapacitors. To test the ion conductivity through membranes made from cellulose nanofibril (CNF) materials, different electrolytes chosen with respect to the Hofmeister series were studied. The CNF samples were oxidised to three different surface charge levels via 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), and a second batch was further cross-linked by periodate oxidation to increase wet strength and stability. The outcome showed that the CNF pre-treatment and choice of electrolyte are both crucial to the ion conductivity through the membranes. Significant specific ion effects were observed for the TEMPO-oxidised CNF. Periodate oxidated CNF showed low ion conductivity for all electrolytes tested due to an inhibited swelling caused by the crosslinking reaction. © 2020 Elsevier Ltd

  • 83. Danielsson, Rolf
    et al.
    Bylund, Dan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Markides, Karin E
    Matched filtering with background suppression for improved quality of base peak chromatograms and mass spectra in liquid chromatography-mass spectrometry2002Inngår i: Analytica Chimica Acta, ISSN 0003-2670, Vol. 454, nr 2, s. 167-184Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A time domain filter that combines the properties of matched filtering and two-fold differentiation is presented. The filter coefficients are given by the second derivative of a Gaussian model peak, controlled by the setting of two parameters related to the chromatographic system. The fundamental characteristics of the filter were derived, and its applicability demonstrated for real liquid chromatography–mass spectrometry (LC–MS) data. The filter is primarily intended as a fast pre-processing step, for a mass chromatogram with 320 scans over 700 mass channels the computation time was 0.6 s on a standard PC. Base peak chromatograms with improved peak detection capability and mass spectra useful for compound identification were obtained with filtered data. The most significant effect of the described filter is background reduction due to the differentiation, which in combination with the matched filter can be performed with maintained or even improved signal-to-noise ratio.

  • 84. De la Rosa, M. P.
    et al.
    Holmström, Sara J. M.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Sposito, G
    Tebo, B. M.
    Bargar, J
    Systematic study of the effect of pH on the structure and reactivity of Mn oxide produced by Bacillus sp., strain SG-1: Gordon Research Conferences - Environmental Bioinorganic Chemistry 2006. Proctor Academy , Andover, NH, USA, 18-23 June, 2006 ; Poster2006Konferansepaper (Fagfellevurdert)
  • 85.
    Deiana, L.
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Ghisu, L.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Córdova, O.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Zhang, Renyun
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Efficient and highly enantioselective aerobic oxidation-michael- carbocyclization cascade transformations by integrated Pd(0)-CPG nanoparticle/chiral amine relay catalysis2014Inngår i: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, Vol. 46, nr 10, s. 1303-1310Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of highly diastereo- and enantioselective aerobic oxidation-Michael-carbocyclization cascade transformations by integrated heterogeneous Pd(0)-CPG nanoparticle/chiral amine relay catalysis are disclosed. The heterogeneous Pd(0)-CPG nanoparticle catalysts were efficient for both the sequential aerobic oxidation and dynamic kinetic asymmetric Michael- carbocyclization transformations, resulting in 1) oxidation of a variety of allylic alcohols to enals and 2) formation of cyclopentenes containing an all-carbon quaternary stereocenter in good to high yields with up to 20:1 dr and 99.5:0.5 er. © Georg Thieme Verlag Stuttgart.New York.

  • 86. Deiana, L
    et al.
    Zhao, G-L
    Lin, S
    Dziedzic, P
    Zhang, Q
    Leijonmarck, H
    Còrdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Organocatalytic enantioselective aziridination of α-substituted α,β-unsaturated aldehydes: Asymmetric synthesis of terminal aziridines2010Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 352, nr 18, s. 3201-3207Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The first example of a highly enantioselective organocatalytic aziridination of α-substituted α,β-unsaturated aldehydes is presented. The reaction is catalyzed by simple chiral amines and gives access to highly functional terminal azirdines containing an α-tertiary amine stereocenter in high yields and enantiomeric ratios (95.5:4.5-98:2)

  • 87.
    Deiana, Luca
    et al.
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Palo-Nieto, Carlos
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Verho, Oscar
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Johnston, Eric V
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Highly Enantioselective Cascade Transformations by Merging Heterogeneous Transition Metal Catalysis with Asymmetric Aminocatalysis2012Inngår i: Scientific reports, ISSN 2045-2322, Vol. 2, s. Art. no. 851-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concept of combining heterogeneous transition metal and amine catalysis for enantioselective cascade reactions has not yet been realized. This is of great advantage since it would allow for the recycling of expensive and non-environmentally friendly transition metals. We disclose that the use of a heterogeneous Pd-catalyst in combination with a simple chiral amine co-catalyst allows for highly enantioselective cascadetransformations. The preparative power of this process has been demonstrated in the context of asymmetric cascade Michael/carbocyclizationtransformations that delivers cyclopentenes bearing an all carbon quaternary stereocenters in high yields with up to 30:1 dr and 99% ee. Moreover, a variety of highly enantioselective cascade hetero-Michael/ carbocyclizations were developed for the one-pot synthesis of valuable dihydrofurans and pyrrolidines (up to 98% ee) by using bench-stable heterogeneous Pd and chiral amines as co-catalysts. © 2012 Macmillan Publishers Limited. All rights reserved.

  • 88.
    Deiana, Luca
    et al.
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, S-10691 Stockholm, Sweden.
    Nieto, Carlos Palo
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Jiang, Yan
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Johnston, Eric
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Verho, Oscar
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Combined multistep heterogeneous transition metal catalysis and aminocatalysis for asymmetric cascade reactions2013Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 245, s. Meeting abstract 147-ORGN-Artikkel i tidsskrift (Annet vitenskapelig)
  • 89.
    Deiana, Luca
    et al.
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Dziedzic, Pawel
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Zhao, Gui-Ling
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Vesely, Jan
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Ibrahem, Ismail
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Rios, Ramon
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Sun, Junliang
    Stockholm Univ, Arrhenius Lab, Dept Struct Chem, S-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik. Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Catalytic Asymmetric Aziridination of alpha,beta-Unsaturated Aldehydes2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 28, s. 7904-7917Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development, scope, and application of the highly enantioselective organocatalytic aziridination of α,β-unsaturated aldehydes is presented. The aminocatalytic azirdination of α,β-unsaturated aldehydes enables the asymmetric formation of β-formyl aziridines with up to >19:1 d.r. and 99 % ee. The aminocatalytic aziridination of α-monosubstituted enals gives access to terminal α-substituted-α-formyl aziridines in high yields and up to 99 % ee. In the case of the organocatalytic aziridination of disubstituted α,β-unsaturated aldehydes, the transformations were highly diastereo- and enantioselective and give nearly enantiomerically pure β-formyl-functionalized aziridine products (99 % ee). A highly enantioselective one-pot cascade sequence based on the combination of asymmetric amine and N-heterocyclic carbene catalysis (AHCC) is also disclosed. This one-pot three-component co-catalytic transformation between α,β-unsaturated aldehydes, hydroxylamine derivatives, and alcohols gives the corresponding N-tert-butoxycarbonyl and N-carbobenzyloxy-protected β-amino acid esters with ee values ranging from 92-99 %. The mechanisms and stereochemistry of all these catalytic transformations are also discussed.

  • 90.
    Deiana, Luca
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Ghisu, Lorenza
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Verho, Oscar
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Johnston, Eric V.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Hedin, Niklas
    Berzelii Center EXSELENT, Stockholm University, SE-106 91 Stockholm, Sweden.
    Bacsik, Zoltan
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden .
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Enantioselective Heterogeneous Synergistic Catalysis for Asymmetric Cascade Transformations2014Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 356, nr 11-12, s. 2485-2492Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A modular design for a novel heterogeneous synergistic catalytic system, which simultaneously activates the electrophile and nucleophile by the combined activation modes of a separate metal and non-metal catalyst, for asymmetric cascade transformations on a solid surface is disclosed. This modular catalysis strategy generates carbocycles (up to 97.5: 2.5 er) as well as spirocyclic oxindoles (97.5: 2.5 to > 99: 0.5 er), containing all-carbon quaternary centers, in a highly enantioselective fashion via a one-pot dynamic relay process.

  • 91.
    Deiana, Luca
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Jiang, Yan
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Palo-Nieto, Carlos
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Incerti-Pradillos, Celia A.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Verho, Oscar
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Tai, Cheuk-Wai
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden .
    Johnston, Eric V.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Cordova, Armando
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Combined Heterogeneous Metal/Chiral Amine: Multiple Relay Catalysis for Versatile Eco-Friendly Synthesis2014Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 53, nr 13, s. 3447-3451Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein is described a versatile and broad synergistic strategy for expansion of chemical space and the synthesis of valuable molecules (e.g. carbocycles and heterocycles), with up to three quaternary stereocenters, in a highly enantioselective fashion from simple alcohols (31examples, 95:5 to >99.5:0.5 e.r.) using integrated heterogeneous metal/chiral amine multiple relay catalysis and air/O-2 as the terminal oxidant. A novel highly 1,4-selective heterogeneous metal/amine co-catalyzed hydrogenation of enals was also added to the relay catalysis sequences.

  • 92. Deiana, Luca
    et al.
    Zhao, Gui-Ling
    Dziedzic, Pawel
    Rios, Ramon
    Vesely, Jan
    Ekström, Jesper
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    One-pot highly enantioselective catalytic Mannich-type reactions between aldehydes and stable a-amido sulfones: Asymmetric synthesis of b-amino aldehydes and b-amino acids2010Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 51, nr 2, s. 234-237Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A highly enantioselective catalytic route to carbamate- and benzoate-protected β-amino aldehydes and β-amino acids is presented. The amino acid-catalyzed one-pot asymmetric reaction between unmodified aldehydes and α-amido sulfones gives the corresponding β-amino compounds with up to 95:5 dr and 97–>99% ee.

  • 93.
    Dijkstra, F. A.
    et al.
    Laboratory of Soil Science and Geology, PO Box 37, 6700 AA Wageningen, PAYS-BAS.
    Geibe, Christine
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Holmström, Sara
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Lundström, Ulla
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    van Breemen, N.
    Laboratory of Soil Science and Geology, PO Box 37, 6700 AA Wageningen, PAYS-BAS.
    The effect of organic acids on base cation leaching from forest floor under six north American tree species2001Inngår i: European Journal of Soil Science, ISSN 1351-0754, E-ISSN 1365-2389, Vol. 52, nr 2, s. 205-214Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Organic acidity and its degree of neutralization in the forest floor can have large consequences for base cation leaching under different tree species. We investigated the effect of organic acids on base cation leaching from the forest floor under six common North American tree species. Forest floor samples were analysed for exchangeable cations and forest floor solutions for cations, anions, simple organic acids and acidic properties. Citric and lactic acid were the most common of the acids under all species. Malonic acid was found mainly under Tsuga canadensis (hemlock) and Fagus grandifolia (beech). The organic acids were positively correlated with dissolved organic carbon and contributed significantly to the organic acidity of the solution (up to 26%). Forest floor solutions under Tsuga canadensis contained the most dissolved C and the most weak acidity among the six tree species. Under Tsuga canadensis we also found significant amounts of strong acidity caused by deposition of sulphuric acid from the atmosphere and by strong organic acids. Base cation exchange was the most important mechanism by which acidity was neutralized. Organic acids in solution from Tsuga canadensis, Fagus grandifolia, Acer rubrum (red maple) and Quercus rubra (red oak) were hardly neutralized while much more organic acidity was neutralized for Acer saccharum (sugar maple) and Fraxinus americana (white ash). We conclude that quantity, nature and degree of neutralization of organic acids differ among the different tree species. While the potential for base cation leaching with organic acids from the forest floor is greatest under Tsuga canadensis, actual leaching with organic anions is greatest under Acer saccharum and Fraxinus americana under which the forest floor contains more exchangeable cations than does the strongly acidified forest floor under Tsuga canadensis.

  • 94.
    Duan, Ran
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    On Shaping Mechanical Properties of Lignocellulosic Materials by Benign Chemical Processing2016Licentiatavhandling, med artikler (Annet vitenskapelig)
  • 95. Duckworth, O W
    et al.
    Holmström, Sara J M
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Peña, J
    Sposito, G
    Biogeochemistry of iron oxidation in a circumneutral freshwater habitat2009Inngår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 260, nr 3-4, s. 149-158Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Iron(II) oxidation in natural waters at circumneutral pH, often regarded as an abiotic process, is frequently biologically mediated at iron-rich redox gradients. West Berry Creek, a small circumneutral tributary that flows through a mixed coniferous forest in Big Basin State Park, California, contains localized iron (hydr)oxide precipitates at points along its course where anoxic groundwater meets oxygenated creek water. These mixing zones establish redox gradients that may be exploited by microbes forming microbial mats that are intimately associated with iron (hydr)oxide precipitates. Water sampling revealed strong correlations between the concentrations of aqueous inorganic species, suggesting a rock-weathering source for most of these solutes. Liquid chromatography-electrospray ionization-mass spectrometry techniques detected significant concentrations of organic exudates, including low molecular mass organic acids and siderophores, indicating that active biogeochemical cycling of iron is occurring in the creek. X-ray diffraction and elemental analysis showed the precipitates to be amorphous, or possibly poorly crystalline, iron-rich minerals. Clone libraries developed from 16S rDNA sequences extracted from microbial mat communities associated with the precipitates revealed the presence of microorganisms related to the neutrophilic iron oxidizing bacteria Gallionella and Sideroxydans. Sequences from these libraries also indicated the presence of significant populations of organisms related to bacteria in the genera Aquaspirillum, Pseudomonas, Sphingomonas, and Nitrospira. These geosymbiotic systems appear to be significant not only for the biogeochemical cycling of iron in the creek, but also for the cycling of organic species, inorganic nutrients, and trace metals.

  • 96.
    Edlund, Håkan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Berglund, Per
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Jensen, M
    Hedenström, Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Högberg, Hans-Erik
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Resolution of 2-Methylalkanoic Acids: Enantioselective Esterification with Long Chain Alcohols Catalysed by Candida rugosa Lipase1996Inngår i: Acta Chemica Scandinavica, ISSN 0904-213X, Vol. 50, nr 8, s. 666-671Artikkel i tidsskrift (Fagfellevurdert)
  • 97.
    Edlund, Håkan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Norgren, Magnus
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Different Types of Aggregation and Aggregate Structures in Aqueous Kraft Lignin Solutions. 2002Inngår i: Proceedings. 7th EWLP, 2002, s. 297-300Konferansepaper (Annet vitenskapelig)
  • 98.
    Edlund, Håkan
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Norgren, Magnus
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Ion Specific Differences in Salt Induced Precipitation of Kraft Lignin2002Inngår i: Proceedings 7th EWLP, Turku, Finland, Aug 26–29, 2002, 2002, s. 75-78Konferansepaper (Fagfellevurdert)
  • 99.
    Eivazihollagh, Alireza
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Bäckström, Joakim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Norgren, Magnus
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Electrochemical recovery of copper complexed by DTPA and C12-DTPA from aqueous solution using a membrane cell2018Inngår i: Journal of chemical technology and biotechnology (1986), ISSN 0268-2575, E-ISSN 1097-4660, Vol. 93, nr 5, s. 1421-1431Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND

    The electrochemical recovery of copper from DTPA and C12-DTPA (a surface-active derivative of DTPA) complex solutions was investigated in a membrane flow cell. Electrolysis time, solution flow rate, applied current density, and solution pH were evaluated.

    RESULTS

    The chelating surfactant C12-DTPA can promote the kinetics of copper electrodeposition more than DTPA depending on the experimental conditions. At a current density of 30 A m–2, a solution flow rate of 0.6 L min–1, and pH 10 after 180 min treatment, the copper recovery and current efficiency were 50% and 43.3%, respectively, in the Cu(II)-DTPA system and about 65% and 53.6%, respectively, in the Cu(II)-C12-DTPA system. The differences in the amount of recovery could be explained in terms of differences in the diffusion of copper complexes with DTPA and C12-DTPA to the cathode, as well as their solution behavior and pH-dependent conditional stability constants (log10 K’CuDTPA3-).

    CONCLUSION

    Electrochemical methods could be effectively combined with foam flotation for the chelating surfactant C12-DTPA, to recover copper and C12-DTPA. This makes the overall treatment more sustainable, and can be helpful in complying with the increasingly stringent environmental regulations

  • 100.
    Eivazihollagh, Alireza
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Bäckström, Joakim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Norgren, Magnus
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Edlund, Håkan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Influences of the operational variables on electrochemical treatment of chelated Cu(II) in alkaline solutions using a membrane cell2017Inngår i: Journal of chemical technology and biotechnology (1986), ISSN 0268-2575, E-ISSN 1097-4660, Vol. 92, nr 6, s. 1436-1445Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND

    The electrochemical recovery of copper and chelating agent from their complex solution using a membrane flow cell was investigated. The parameters electrolysis time, solution pH, current density, and temperature were investigated.

    RESULTS

    Electrochemical investigation indicated that chelating ligands can be recovered by the electrodeposition of copper ions on the cathode. For copper and EDTA recovery, the results indicated that recovery efficiency was affected by time, current density, and temperature. The recovery process was not influenced by pH in the range studied (pH 8–12), which can be explained by the low variation in the conditional stability constant, i.e. Δlog10 K' ≤ 0.7, over the pH range. However, when NTA, EDTA, and DTPA were compared, the results indicated that the recovery efficiency decreased as the conditional stability constant of the chelating agent–Cu(II) complex increased. The maximum current efficiency of copper and EDTA recovery after 5 h of treatment was approximately 85%, whereas the recovery was 80% of the initial concentration (0.05 mol L−1) at a current density of 1 A dm−2, temperature of 333 K, and pH of 10.

    CONCLUSION

    Relatively high recovery efficiency makes the process fairly sustainable and hinders the discharge of copper ions and chelating ligands as pollutants into the environment. 

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