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  • 1.
    Bhaskar, Raju G.
    et al.
    Luleå tekniska universitet.
    Subrahmanyam, T.V
    Luleå tekniska universitet.
    Sun, Z.
    Luleå tekniska universitet.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Shear-flocculation of quartz1991Ingår i: International Journal of Mineral Processing, ISSN 0301-7516, E-ISSN 1879-3525, Vol. 32, nr 3-4, s. 283-294Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present work deals with the shear-flocculation of quartz in aqueous solutions of dodecylamine chloride. The variables studied include pH, concentration of the amine, size of the coarse particles, stirring speed and time. The zeta potentials were correlated with flocculation behaviour. It was observed that particle hydrophobicity and pH were most important since the dodecylamine chloride-solution reactions are pH-and concentration-dependent.

  • 2.
    Bo, Qi-Bing
    et al.
    Institute of Chemistry and Chemical Engineering, University of Jinan.
    Sun, Zhong-Xi
    Institute of Chemistry and Chemical Engineering, University of Jinan.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    A new family of 3D 3d-4f heterometallic frameworks comprising 1D inorganic lanthanide ladders and organic Cu-bipyridine chains2008Ingår i: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 10, nr 2, s. 232-238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new family of the 3D heterometallic coordination polymers [{Ln2(SO4)2(H2O)2(pydc)2Cu2 (bpy)2·2(H2O)}]n (Ln = Sm ( 1), Eu ( 2), Gd ( 3), Tb ( 4) and Dy ( 5); pydc = 2,6-pyridine-dicarboxylate anion; bpy= 4,4-bipyridine) have successfully been synthesized under solvothermal conditions (H2O/ethanol). All the coordination polymers obtained were characterized by elemental analysis, FT-IR analysis, differential thermal analysis/thermogravimetry (DTA/TG), fluorescent spectra and single crystal X-ray diffraction analysis. The most intriguing structural feature is that all the compounds exhibit 3D frameworks with 1D inorganic lanthanide ladders and organic CuI-bipyridine chains, which represent two types of 3d/4f coordination polymers (form I: Ln = Sm and Eu; form II: Ln = Gd, Tb and Dy) as the result of a so-called gadolinium break effect. Additionally, compounds 2 and 4 showed the characteristic emission spectra of the EuIII and TbIII ions, respectively, and appeared to have good fluorescence properties, while 1, 3 and 5 emitted fluorescence resembling CuI complexes. To our knowledge, the investigation of the

  • 3.
    Bredyuk, O. A.
    et al.
    Russian Adademy of Sciences.
    Gerasimenko, A. V.
    Russian Adademy of Sciences.
    Lutsenko, I. A.
    Russian Adademy of Sciences.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Structural organization of cadmium(II) and copper(II) dithiocarbamate complexes with dialkyl-substituted and cyclic ligands: Synthesis, single-crystal X-ray diffraction, EPR, and CP/MAS13C, 15N, and 113Cd NMR2005Ingår i: Russian Journal of Inorganic Chemistry, ISSN 0036-0236, E-ISSN 1531-8613, Vol. 50, nr 11, s. 1710-1726Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A comparative study of polynuclear thallium complexes with dialkyldithiocarbamates [Tl2{S2CNR2} 2]n (R = CH3, i-C3H7, C4H9, and i-C4H9; R2 = (CH2)6) was performed by solid-state 13C and 15N CP/MAS NMR spectroscopy. The dithiocarbamate groups were found to be structurally equivalent in the complexes studied. An increase in the positive inductive effect of alkyl substituents at the N atom increased 15N chemical shifts as a result of a combination of positive inductive effect of the alkyl substituents and the mesomeric effect of =NC(S)S-groups. The first representative of thallium(I) complexes with a cyclic dithiocarbamate ligand [Tl2{S2CN(CH2) 6}2]n was obtained. Its molecular structure was determined from X-ray diffraction data. The β-form of the isotope-substituted complex [63/65CuTl2{S 2CN(CH2)6}4] was obtained and examined by EPR spectroscopy. The EPR spectra were modeled at the second order of the perturbation theory. The spin density at the thallium atoms was calculated and its distribution over the AOs of thallium was determined.

  • 4.
    Casellas, D.
    et al.
    Universitat Politècnica de Catalunya.
    Cumbrera, F. L.
    Universidad de Extremadura.
    Sánchez-Bajo, F.
    Universidad de Extremadura.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Llanes, L.
    Universitat Politècnica de Catalunya.
    Anglada, M.
    Universidad de Extremadura.
    On the transformation toughening of Y-ZrO2 ceramics with mixed Y-TZP/PSZ microstructures2001Ingår i: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 21, nr 6, s. 765-777Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Heat treatment of Y-TZP at high temperatures produces materials with a mixed Y-TZP/PSZ phase assemblage, which exhibit a unique combination of high mechanical strength and fracture toughness, uncommon in zirconia ceramics. The microstructure and crack growth resistance of the Y-TZP/PSZ materials developed by treating at 1650°C in air a fine-grained Y-TZP was studied. XRD as well as Raman spectroscopy results indicate that the obtained microstructure allow the retention of large tetragonal grains (up to ˜4 μm), resulting in both phase transformability enhancement and pronounced R-curve behavior. The large transformation zone, discerned from accurate measurements with Raman microprobe spectroscopy, sustains the above assessment and points out tetragonal to monoclinic phase transformation as the main toughening mechanism in the investigated Y-TZP/PSZ microstructures. This was confirmed by satisfactory agreement between the transformation toughening estimated from numerical analysis and the crack shielding experimentally determined from the R-curve measurements.

  • 5.
    Chanturiya, Valentine
    et al.
    Institute of Problems of Complex Development of Mineral Resources.
    Makarov, Victor
    Kola Science Centre, Russian Academy of Sciences, Apatity.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Makarov, Dimitriy
    Kola Science Centre, Russian Academy of Sciences, Apatity.
    Vasil'eva, Tatyana
    Kola Science Centre, Russian Academy of Sciences, Apatity.
    Trofimenko, Tatyana
    Kola Science Centre, Russian Academy of Sciences, Apatity.
    Kuznetsov, Victor
    Kola Science Centre, Russian Academy of Sciences, Apatity.
    The effect of crystallochemical peculiarities of nickel sulphide minerals on flotation of copper-nickel ore2004Ingår i: International Journal of Mineral Processing, ISSN 0301-7516, E-ISSN 1879-3525, Vol. 74, nr 1-4, s. 289-301Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flotation kinetics of pentlandite and violarite contained in copper-nickel ores and the effect of crystallochemical peculiarities of the minerals on their flotation features are studied. Studies of the effect of pentlandite crystallochemical features on its flotation properties have shown that the easiest to float is nickel-enriched pentladite, cobalt-enriched one being somewhat worse the worst being iron-enriched one. Pentlandite was found to be much better recovery to flotation concentrates than violarite. So, the process of violaritization of the surface of pentlandite grains, which may occur during the flotation, will negatively affect its characteristics.

  • 6.
    Du, Qing
    et al.
    Luleå tekniska universitet.
    Sun, Zhongxi
    Luleå tekniska universitet.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Hongxiao, Tang
    Research Center for Eco-Environmental Sciences, Academia Sinica.
    Acid-base properties of aqueous illite surfaces1997Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 187, nr 1, s. 221-231Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, the acid-base properties of illite/water suspensions are examined using the constant capacitance surface complexation model. On the basis of results of potentiometric titrations and solubility experiments, we conclude that the proton reactions in the supernatants of illite suspensions can be successfully represented by proton reactions of Al(H2O)63+and Si(OH)4in water solutions. For illustrating the acidic characteristics of aqueous illite surfaces, two surface protonation models are proposed: (1) one site-one pKamodel, ≡SOH ≡SO-+ H+, pKaint= 4.12-4.23; (2) two sites-two pKas model, ≡SIOH ≡SIO-+ H+, pKintaI= 4.17-4.44, and ≡SIIOH ≡SIIO-+ H+, [dipKintaII= 6.35-7.74. Evaluation of these two models indicates that both of them can give good descriptions of the experimental data of systems with different illite concentrations and ionic strengths and that the one site-one pKamodel can be considered as a simplification of the two sites-two pKas model. Since both models assume only deprotonation reactions at the illite surfaces, they suggest that the surface behavior of the illite is similar to that of amorphous SiO2. Model assumptions, experimental procedures, and evaluative criteria are detailed in the paper.

  • 7.
    Du, Qing
    et al.
    Luleå tekniska universitet.
    Sun, Zhongxi
    Luleå tekniska universitet.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Tang, Hongxiao
    Research Center for Eco-Environmental Sciences, Academia Sinica.
    Adsorption of copper at aqueous illite surfaces1997Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 187, nr 1, s. 232-242Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we conducted potentiometric titrations, batch adsorption experiments and FT-IR analysis to study the uptake of copper in illite/water suspensions and then applied the constant capacitance surface complexation model to interpret the reaction mechanism at the aqueous illite surfaces. Our research shows that the copper adsorption at these surfaces is strongly dependent on pH and that the adsorption causes a deprotonation of surface groups. We propose that the uptake of copper in the carbonate-free illite suspensions can be explained by the formation of mononuclear surface complexes, ≡SOCu+and ≡SOCuOH, and a multinuclear surface complex, ≡SOCu2(OH)2+, followed by the formation of a bulk precipitate, Cu(OH)2(s), or a surface precipitate, ≡SOCu2(OH)3(sp). For the illite suspensions containing carbonates, we propose that the copper-illite interaction can be depicted by the formation of mononuclear surface complexes, ≡SOCu+and ≡SOCuOH, followed by the formation of a copper hydroxylcarbonate precipitate, Cu2(OH)2CO3(s), rather than a copper hydroxide precipitate. The existence of Cu2(OH)2CO3(s) in the carbonate-containing illite suspensions was identified by FT-IR analysis

  • 8.
    Du, Qing
    et al.
    Luleå tekniska universitet.
    Sun, Zhongxi
    Luleå tekniska universitet.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Tang, Hongxiao
    SKLEAC, Research Center for Eco–Environmental Sciences, Academia Sinica.
    Complexations in illite-fulvic acid-Cu2+ systems1999Ingår i: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 33, nr 3, s. 693-706Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As part of an extended project to illustrate how heavy metals are complexed by natural aquatic particles, we conducted various experiments to study the adsorption of fulvic acid (FA) at aqueous illite surfaces and the complexation of heavy metal copper(II) in illite-FA bi-complexant systems. By analyzing batch adsorption and potentiometric titration data, we found that (i) the adsorption of FA by illite decreases with increases in pH values and its pH adsorption edge resembles those of SiO2-FA and montmorillonite-FA systems described by other researchers, (ii) it is possible to effectively simulate the complexation of Cu2+ ions in illite-FA bi-complexant systems by taking it to be an additive complexation of two mono-complexant systems (FA-Cu2+ and illite-Cu2+) and (iii) FA can inhibit the retention of heavy metals at solid surfaces by forming soluble complexes with metal ions. The above results and conclusions are supported by FT-IR analysis of various illite-FA-Cu2+ systems

  • 9.
    Dyer, Chris D.
    et al.
    University of Southampton.
    Hendra, Patrick J.
    University of Southampton.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    The Raman spectroscopy of cement minerals under 1064 nm excitation1993Ingår i: Spectrochimica Acta. Part A, Molecular Spectroscopy, ISSN 0584-8539, Vol. 49, nr 5-6, s. 715-722Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The prospects for near-IR-excited Raman scattering from cement minerals are discussed, and a very unusual result concerning the intensity of the spectra is presented.

  • 10.
    Dyer, Chris
    et al.
    University of Southampton.
    Hendra, Patrick J.
    University of Southampton.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Surface hydration of aqueous γ-Al2O3 studied by Fourier transform Raman and infrared spectroscopy-I.: Initial results1993Ingår i: Spectrochimica Acta. Part A, Molecular Spectroscopy, ISSN 0584-8539, Vol. 49, nr 5-6, s. 691-705Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The hydration of γ-Al2O3 has been studied by Fourier transform (FT) Raman and infrared (IR) spectroscopy, and by X-ray diffraction (XRD). The initial findings are presented, along with a discussion of the possible causes for the major spectral changes that occur after hydration. The aims of the study and ongoing research are described.

  • 11. Forsling, Willis
    Chemistry of electrolytic condensers1986Ingår i: Kemisk tidskrift, ISSN 0039-6605, Vol. 98, nr 2, s. 38-41Artikel i tidskrift (Övrigt vetenskapligt)
  • 12.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Research at the interface between industrial needs and scientific demands2004Ingår i: Proceedings, International Seminar on Mineral Processing Technology (MPT-2004): 19 - 21 February 2004 / [ed] G.V. Rao; V.N. Misra, New Delhi: Allied Publishers Ltd , 2004Konferensbidrag (Refereegranskat)
  • 13.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Utveckling av aluminiumoxidstabilisering1989Rapport (Övrigt vetenskapligt)
  • 14.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Vad ska vi göra med kärnkraftsavfallet?2003Ingår i: THULE: Kungl. Skytteanska Samfundets Årsbok 2003, Umeå: Kungl. Skytteanska samfundet , 2003, s. 161-172Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 15. Forsling, Willis
    et al.
    Holmgren, Allan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Betydelsen av grundläggande forskning för mineraltekniska processer2006Ingår i: Konferens i mineralteknik / [ed] Marianne Thomaeus; Eric Forssberg, Föreningen Mineralteknisk Forskning / Swedish Mineral Processing Research Association , 2006Konferensbidrag (Övrigt vetenskapligt)
  • 16.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samskog, Per-Olof
    Research at the interface between industrial needs and scientific demands2005Ingår i: Bergsmannen med Jernkontorets Annaler, ISSN 0284-0448, nr 3, s. 49-52Artikel i tidskrift (Övrigt vetenskapligt)
  • 17.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Sjöberg, Staffan
    Avdelningen för oorganisk kemi, Umeå universitet.
    Ytkomplexbildning vid sulfidmineralflotation1989Ingår i: Konferens i mineralteknik: Luleå 14-16 februari 1989 / [ed] Börje Sköld; Eric Forssberg, MinFo , 1989, s. 83-96Konferensbidrag (Övrigt vetenskapligt)
  • 18.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Sterte, Johan
    Skogsindustrin satsar på forskning och utbildning i Luleå: professur i Kemisk Apparatteknik inrättad1997Ingår i: Svensk papperstidning, Nordisk cellulosa, ISSN 1101-766X, nr 9, s. 49-50Artikel i tidskrift (Övrigt vetenskapligt)
  • 19.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Su, Fen-Wei
    Luleå tekniska universitet.
    Sun, Zheng-Xi
    Luleå tekniska universitet.
    Samskog, Per-Olof
    LKAB utveckling.
    Forsmo, Seija
    LKAB utveckling.
    Karakterisering av magnetitytor i vattensuspension1994Ingår i: Konferens i mineralteknik: Luleå, 2-4 februari 1993 / [ed] Marianne Thomaeus; Eric Forssberg, MinFo , 1994, s. 231-244Konferensbidrag (Övrigt vetenskapligt)
  • 20.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Sun, Zhong-Xi
    Luleå tekniska universitet.
    Use of surface complexation models in sulphide mineral flotation1997Ingår i: International Journal of Mineral Processing, ISSN 0301-7516, E-ISSN 1879-3525, Vol. 51, nr 1-4, s. 81-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Surface complexation modelling is introduced to investigate the surface reactions in a mixed galena and sphalerite flotation system. Computer-assisted calculations based on surface complexation modelling (SCM) are performed to obtain the mineral surface distribution of ethyl xanthate as well as carbonate and excess sulphide ions as a function of pH. The significance of pe is demonstrated by computing the mineral surface speciation in a flotation system with xanthate and excess of sulphide ions. The results are used to evaluate the influences of pH, pe, the concentration of xanthate, sulphide or carbonate ions to the mineral flotability. The flotation mechanisms in galena-sphalerite system are discussed based on SCM.

  • 21.
    Forsling, Willis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Wu, Liuming
    Luleå tekniska universitet.
    Adsorptionsmekanism för organisk tryckare på apatit och kalcit1992Ingår i: Konferens i mineralteknik: Luleå, 4-5 februari, 1992 / [ed] Börje Sköld; Eric Forssberg, MinFo , 1992, s. 65-74Konferensbidrag (Övrigt vetenskapligt)
  • 22. Fredriksson, Andreas
    et al.
    Holmgren, Allan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Kinetics of collector adsorption on mineral surfaces2005Ingår i: Centenary of flotation symposium / [ed] Graeme J. Jameson, The Australian Institute of Mining and Metallurgy , 2005, s. 433-437Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the present study infrared attenuated total reflection (IR-ATR) was used to monitor the rate of in situ adsorption of heptyl xanthate on a layer of zinc sulfide synthesised on a germanium ATR crystal. The zinc sulfide surface was characterised using x-ray photoelectron spectroscopy (XPS). The absorbance of heptyl xanthate measured increased with increasing bulk concentration of the adsorbate up to an equilibrium plateau value corresponding to a fractional coverage of the surface sites of the substrate. For the adsorption from solutions of concentrations between 10-3 and 10-5 M, the rate of adsorption increased with increasing bulk concentration. At higher concentrations the measured absorbance should be corrected for the absorbance due to the concentration of xanthate in bulk solution. The present work provides a discussion of this correction. Assuming the adsorption stage to be rate-controlling and proportional both to the concentration of the adsorbing species in solution and unreacted surface area, a rate law governing this type of transient adsorption kinetics was derived. By means of absorbance data for the concentrations 0.1 and 0.01 mM, die rate constant of adsorption was calculated. From the initial part of a Langmuir adsorption isotherm, the absorbance at monolayer coverage and the equilibrium constant of adsorption could be estimated.

  • 23. Fredriksson, Andreas
    et al.
    Holmgren, Allan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Kinetics of collector adsorption on mineral surfaces2006Ingår i: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 19, nr 6-8, s. 784-789Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the present study infrared attenuated total reflection (IR-ATR) was used to monitor the rate of in situ adsorption of heptyl xanthate on a layer of zinc sulphide synthesized on a germanium ATR crystal. The zinc sulphide surface was characterized using X-ray photoelectron spectroscopy (XPS). The absorbance of heptyl xanthate measured increased with increasing bulk concentration of the adsorbate up to an equilibrium plateau value corresponding to a fractional coverage of the surface sites of the substrate. For the adsorption from solutions of concentrations between 10−3 and 10−5 M, the rate of adsorption increased with increasing bulk concentration. At higher concentrations the measured absorbance should be corrected for the absorbance due to the concentration of xanthate in bulk solution. The present work provides a discussion of this correction. Assuming the adsorption stage to be rate-controlling and proportional both to the concentration of the adsorbing species in solution and unreacted surface area, a rate law governing this type of transient adsorption kinetics was derived. By means of absorbance data for the concentrations 0.1 and 0.01 mM, the rate constant of adsorption was calculated. From the initial part of a Langmuir adsorption isotherm, the absorbance at monolayer coverage and the equilibrium constant of adsorption could be estimated.

  • 24.
    Frost, Ray L.
    et al.
    Queensland University of Technology.
    Forsling, Willis
    Holmgren, Allan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Kloprogge, Theo
    Queensland University of Technology.
    Kristof, Janos
    University of Veszprem.
    Raman spectroscopy at temperatures between 298 and 423 K and at 77 K of kaolinites intercalated with formamide1998Ingår i: Journal of Raman Spectroscopy, ISSN 0377-0486, E-ISSN 1097-4555, Vol. 29, nr 12, s. 1065-1069Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Raman spectra of kaolinite and of the formamide-intercalated kaolinite were obtained at both 298 and 77 K using a Raman microprobe equipped with a thermal stage. Upon cooling to 77 K, the band attributed to the inner hydroxyl shifts by 5 cm-1 to lower wavenumbers and the bands assigned to the inner surface hydroxyls move to higher wavenumbers. Upon intercalation of the kaolinite with formamide, an additional Raman band attributed to the formation of a hydrogen-bonded complex between the inner surface hydroxyls and the carbonyl group of the formamide is observed at 3627 cm-1 at 298 K and at 3631 cm-1 at 77 K. Raman spectra of the deintercalation of the formamide-intercalated kaolinite are obtained by using the thermal stage to heat the intercalated kaolinite in situ. A decrease in intensity of the bands formed through intercalation and at the same time an increase in intensity of the inner surface hydroxyl bands are observed. A loss of intensity of the low-wavenumber region of the formamide-intercalated kaolinite is also observed.

  • 25.
    Gu, TR
    et al.
    Beijing University.
    Huang, Z
    Beijing University.
    Sun, Zhong-Xi
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    The ionic exchange coefficients of surfactant counterions at the solid liquid interface .1: The ionic exchange coefficients of F- and CL- on adsorbed Cetyltrimethylammonium Bromide at the Silica water interface1991Ingår i: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. 45, nr 5, s. 526-528Artikel i tidskrift (Refereegranskat)
  • 26.
    Gustavsson, Håkan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Weihed, Pär
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Forssberg, Eric
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Norrländsk vattenkraft och gruvnäring: två svenska välståndsbyggare2009Ingår i: Thule: Kungl. Skytteanska samfundets årsbok 2009, Umeå: Kungl. Skytteanska samfundet , 2009, s. 331-345Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 27.
    Gärd, Rune
    et al.
    Luleå University of Technology.
    Holmgren, Allan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Spectroscopic Studies of Dextrin Adsorption onto Colloidal ZnS1997Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 194, nr 2, s. 319-325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The interaction of dextrin with colloidal ZnS has been investigated through adsorption studies and FT-IR spectroscopy in the 4000-400 cm-1range. The adsorption capacity is estimated to be around 1 mg/m2. Maximum adsorption is found to be constant below pH ≈7 and to increase with pH at least up to pH 11. Eighty percent of maximum adsorption is achieved within 3 min after addition of the dextrin. Based upon FT-IR studies and titration data, an adsorption mechanism is proposed.

  • 28.
    Gärd, Rune
    et al.
    Luleå University of Technology.
    Sun, Zhong-Xi
    Luleå University of Technology.
    Forsling, Willis
    FT-IR and FT-Raman studies of colloidal ZnS 1.: Acidic and alkaline sites at the ZnS/water interface1995Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 169, nr 2, s. 393-399Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The surface complexes of colloidal ZnS have been studied using FT-IR and FT-Raman techniques. The absorption bands at 2500 and 1475-1375 cm-1, which are identified as the S-H bond and the Zn-OHCO2 entity, respectively, can be observed under varied conditions of sample stoichiometry and pH. The correlation between surface spectra and the complexation model is evaluated. The relation between the intensities of FT-IR and FT-Raman spectra and particle size is discussed.

  • 29.
    Haigh, J. A.
    et al.
    University of Southampton.
    Hendra, P. J.
    University of Southampton.
    Forsling, Willis
    Extension of a novel method for the examination of oxidized aluminium surfaces using near infrared (NIR) Fourier transform surface enhanced Raman spectroscopy (FT-SERS)1994Ingår i: Spectrochimica Acta. Part A, Molecular Spectroscopy, ISSN 0584-8539, Vol. 50, nr 11, s. 2027-2034Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A SERS active substrate is created on a non-SERS active oxidized aluminium foil. Identification of phthalic acid and phenylphosphate using near infrared FT-SERS is made and possible orientations are proposed.

  • 30.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    A prestudy of the recycling properties of aircraft de-/anti-icing fluids1995Rapport (Övrigt vetenskapligt)
  • 31.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Polubotko, A. M.
    Russian Adademy of Sciences.
    SER spectra analysis of molecules with D-3h and D-6h symmetry groups1998Ingår i: Pure and Applied Optics, ISSN 0963-9659, Vol. 7, nr 1, s. 115-117Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On the basis of the theory of SER spectra, proposed in a previous paper, the SER spectra of 1,3,5-trifluorobenzene, 1,3,5-trideuteriobenzene, benzene and hexafluorobenzene are analysed. It is demonstrated that the bands, caused by the totally symmetric modes and by the mode transforming as the d(z) moment experience large enhancement. The existence of a large number of forbidden bands in the SER spectra is pointed out. Some anomalies in the enhanced spectra are explained by qualitative ideas and by the 'interference phenomenon' of various contributions. It is pointed out that all the observed lines and regularities of the SER spectra can be explained within the framework of the quadrupole and dipole electrodynamical mechanism of the enhancement.

  • 32.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Wu, Liuming
    Luleå tekniska universitet.
    An FT-IR study of Alizarin Red S adsorbed at the fluorapatite-water interface1997Ingår i: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. Suppl. 14, s. 197-199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The diffuse reflectance infrared Fourier transform (DRIFT) technique was used to study sodium 1,2-dihydroxyanthraquinone-3-sulphonate (ARS) adsorbed onto the surface of fluorapatite mineral. The acidity of the water solution was varied between pH 5.4 and pH 8.4. In this pH range the infrared spectra of adsorbed ARS show that the fluorapatite surface contains precipitated calcium-ARS. The chelation of calcium strongly affects the resonance structure of the ARS molecule.

  • 33.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Mohammed-Ziegler, Ildiko
    Hemercy KKT, H-2521 Csolnok, Arany J.u. 28..
    Forsling, Willis
    Ranheimer, Maine
    Luleå tekniska universitet.
    Adsorption of pinosylvin onto different species of fresh and stored wood2010Ingår i: Materials Science: An Indian Journal, ISSN 0974-7486, Vol. 6, nr 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The adsorption of pinosylvin - a natural antifungal agent - on wood was studied by Raman microprobe technique. The adsorption properties of twelve different European wood species were compared. The effect of solvents used, heat treatment, and prolonged storage of the samples on pinosylvin adsorption ability was analysed by means of the Raman intensity ratios of characteristic lines. It was found that the surface concentration of pinosylvin increased when the Lewis acidity of the solvent increased. Besides, adsorption of pinosylvin was less efficient on during prolonged storage the surface of wood became more hydrophobic after prolonged sample storage. In case of heat treatment (1200C, 3 h) no remarkable effect on the amount of adsorbed pinosylvin was observed. Simultaneously, the intensity of the fluorescence background increases. Moreover, the possible influence of B.E.T. specific surface area and lignin content (described by the kappa-value) on the amount of adsorbed pinosylvin was investigated. As revealed, B.E.T. specific surface area did not vary significantly between the different wood species, and therefore it has no significant effect on the efficiency of pinosylvin adsorption. However, the surface concentration of pinosylvin seems to increas with the lignin content. The amount of solvent residue in each sample was measured by diffuse reflectance infrared Fourier transform (DRIFT) technique. For a few wood samples (e.g. pine heartwood, ash, and Hungarian oak) UV-Raman scattering was used to characterize the aromatic components of these wood species. The morphology of the samples was investigated with the aid of scanning electron microscopy (SEM) images. Furthermore, the B.E.T. specific surface area was found not to vary significantly between the different wood species, and therefore it has no significant effect on the efficiency of pinosylvin adsorption. However, the surface concentration of pinosylvin seems to increas with the lignin content. DRIFT spectroscopy was found to be useful to detect solvent residue in the wood samples and the evaporation of polar solvents is a rather slow process. However, it was not possible to detect adsorbed pinosylvin by DRIFT measurements, due to the low concentration and the lack of characteristic frequencies differing from other wood constituents.

  • 34.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Wu, Liuming
    Luleå University of Technology.
    Forsling, Willis
    Fourier transform infrared and Raman study of Alizarin Red S adsorbed at the fluorite-water interface1999Ingår i: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy, ISSN 1386-1425, E-ISSN 1873-3557, Vol. 55, nr 9, s. 1721-1730Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The adsorption of 1,2-dihydroxyanthraqinone-3-sulphonate (ARS) onto the surface of fluorite mineral was studied using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and Fourier transform (FT) Raman spectroscopy. The FT-Raman method proved to be more appropriate for this study when ARS was adsorbed from alkaline solution. At pH 6 both DRIFT and Raman spectra indicate non-precipitated ARS on the fluorite surface. At higher pH Raman spectra indicate ARS to be attached to the fluorite surface through the quinoid group at the 9-position and the α-phenolic oxygen.

  • 35.
    Holmgren, Allan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Wu, Liuming
    Luleå University of Technology.
    Forsling, Willis
    Surface hydration of aqueous calcium minerals as studied by Fourier transform Raman and infrared spectroscopy1994Ingår i: Spectrochimica Acta. Part A, Molecular Spectroscopy, ISSN 0584-8539, Vol. 50, nr 11, s. 1857-1869Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rapid hydration reactions of several calcium minerals are studied using Fourier transform (FT) Raman and infrared (IR) spectroscopy. Oleate adsorption over aqueous synthetic fluorite, calcite and gypsum (pH 9) is investigated and adsorption mechanisms are discussed.

  • 36.
    Horváth, E.
    et al.
    Hungarian Academy of Sciences.
    Kristóf, J. J.
    University of Veszprem.
    Frost, R. L.
    Queensland University of Technology.
    Rintoul, L.
    Queensland University of Technology.
    Rédey, Á.
    University of Veszprem.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Investigation of mandelic acid bonding on Pirkle type chromatographic stationary phases by Raman spectroscopy2000Ingår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 893, nr 1, s. 37-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The bonding of mandelic acid enantiomers has been studied on benzene-leucine, dinitrobenzene-leucine and dinitrobenzene-phenylalanine type chiral stationary phases connected to zeolite A supports. The π-donor, π-acceptor and H-bonding interactions responsible for diastereomer pair formations can be studied under quasi in situ chromatographic conditions by Fourier transform Raman and surface enhanced Raman spectroscopic techniques. Structural differences between diastereomer pairs result in observable spectral differences at a phase load of approx. 50%. It was shown that the decreasing π-acceptor character of the phase is associated with its increasing capability of H-bond formation. Correlating spectral data to chromatographic results it can be concluded that, in addition to H-bonding as well as to π-donor-π-acceptor interactions, steric hindrances due to bulky moieties of either the stationary phase or the analyte molecules are of importance in successful separations.

  • 37.
    Ildikó, Száraz
    et al.
    Luleå University of Technology.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    PVP and azelaic acid adsorption on γ-alumina studied by FT-IR spectroscopy2002Ingår i: Vibrational Spectroscopy, ISSN 0924-2031, E-ISSN 1873-3697, Vol. 29, nr 1-2, s. 15-20Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The adsorption mechanism of poly(1-vinyl-2-pyrrolidone) (PVP) and azelaic acid on synthetic γ-aluminium oxide surfaces was investigated using FT-IR spectroscopy. It was found that PVP adsorption from both aqueous and ethylene glycol (EG) solutions, was negligible, but the presence of the dicarboxylic acid enhances the adsorption of the PVP, due to a hydrophobic interaction between the carbon chains of the polymer and the dicarboxylic acid. The carbon chain of the adsorbed dicarboxylic acid is lateral to the surface and attached to it by both carboxylic groups. The simultaneous adsorption of PVP and azelaic acid was studied as a function of time, pH, solvent and ionic strength of the suspension in order to establish a more detailed surface complexation model. Three main surface complexes were found on the surface of the γ-alumina at low pH in aqueous as well as in EG solutions, while at high pH one of them namely the outer-sphere complex dominates.

  • 38.
    Ingri, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Malinovskiy, Dmitry
    Rodushkin, Ilia
    Baxter, Douglas
    Widerlund, Anders
    Andersson, Per
    Laboratory for Isotope Geology. Swedish Museum of Natural History, Stockholm.
    Gustafsson, Örjan
    Institute of Applied Environmental Research (ITM), Stockholm University.
    Forsling, Willis
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Iron isotope fractionation in river colloidal matter2006Ingår i: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 245, nr 3-4, s. 792-798Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Temporal variations in the iron isotopic composition, δ56Fe between − 0.13‰ and 0.31‰, have been measured in the suspended fraction in a Boreal river. The major mechanism behind these variations is temporal mixing between two types of particles–colloids, Fe-oxyhydroxides and Fe–C colloids. Data in this study indicate that these two types of colloids have different Fe-isotope composition. The Fe–C colloid has a negative δ56Fe value whereas the Fe-oxyhydroxide colloid is enriched in 56Fe. These two types of colloidal matter have different hydrogeochemical origin. The Fe–C colloid reaches the river during storm events when the upper sections of the soil profile (O and E horizons) are flooded by a rising water table. Colloidal Fe-oxyhydroxides reach the river via inflow and subsequent oxidation of groundwater enriched in dissolved Fe(II).

  • 39.
    Ivanov, Alexander
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Gerasimenko, Andrey
    Far Eastern Branch of the Russian Academy of Sciences.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    The unique alternation of conformationally different ('chair'-'saddle') eight-membered metallocycles [Cd2S4P2] in the chains of cadmium dialkyldithiophosphates: 13C, 31P, 113Cd CP/MAS NMR and single-crystal X-ray diffraction studies2005Ingår i: Inorganica Chimica Acta, ISSN 0020-1693, E-ISSN 1873-3255, Vol. 358, nr 9, s. 2585-2594Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    O,O′-Dipropyldithiophosphate and O,O′-dibutyldithiophosphate (Dtph) cadmium(II) complexes were prepared and studied by means of heteronuclear 31P, 113Cd, 31C CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. Linear-chain polynuclear structures have been established for both cadmium(II) complexes, in which each pair of equivalent dithiophosphate groups, playing the same bridging structural function, asymmetrically links the neighbouring cadmium atoms. One remarkable structural feature of the synthesised cadmium(II) compounds is defined by the alternation of two types of conformationally different (‘chair'-‘saddle') eight-membered rings [Cd2S4P2] in the polymeric chains. Therefore, in both 31P NMR and XRD data, the bridging dithiophosphate ligands exhibit structural inequivalence in pairs. The structural states of both Dtph ligands and cadmium atoms have been characterised by the 31P and 113Cd chemical shift tensors, which display a profound axially symmetric and mainly rhombic characters, respectively. All experimental 31P resonances were assigned to the phosphorus structural sites in both resolved structures.

  • 40.
    Ivanov, Alexander
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Korneeva, E.V.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Bukvetskii, B.V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Goryan, Alexander S.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Structural organization of mercury(II) and copper(II) dithiocarbamates from EPR and 13C and 15N MAS NMR spectra and X-ray diffraction analysis2008Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 34, nr 1, s. 59-69Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The structures and spectroscopic properties of mononuclear and binuclear mercury(II) and copper(II) complexes with four dithiocarbamate ligands R 2NC(S)S- (R = CH3, C2H5, or iso-C3H7; R2 = (CH2)6) were studied by solid-state 13C and 15N CP/MAS NMR and EPR spectroscopy. Mercury(II) N,N-cyclohexamethylenedithiocarbamate [Hg 2{S2CN(CH2)6}4] was obtained and characterized in detail by X-ray diffraction analysis at 299 K. The binuclear molecule of the complex is centrosymmetric; the central tricyclic fragment [Hg2S4C2] is in the chair conformation. In the 13C and 15N NMR spectra, the signals were assigned to the dithiocarbamate ligands with different structural functions: bidentate chelating and combined (both chelating and bridging) ones. The differences between the isotropic 15N chemical shifts for the dialkyldithiocarbamate ligands were interpreted in terms of combination of the mesomeric effect of the =NC(S)S-groups and the inductive effect of the alkyl substituents. According to the EPR data, copper(II) in magnetically diluted systems is mainly found in heterobinuclear molecules [CuHg(S2CNR 2)4] and the geometry of the chromophores [CuS 5] approximates to a tetragonal pyramid.

  • 41.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Boström, Dan
    Umeå university.
    Yegao, Y.
    Jingzhou Normal University.
    Rodionova, N. A.
    Blagoveshchensk State Pedagogical University.
    Structural organization and spectral properties of cadmium and nickel(II) O,O"-Di-iso-butyl phosphorodithioate complexes as probed by single-crystal x-ray diffraction and CP/MAS NMR (13C, 31P, 113Cd)2002Ingår i: Doklady. Physical chemistry, ISSN 0012-5016, E-ISSN 1608-3121, Vol. 387, nr 4-6, s. 299-303Artikel i tidskrift (Refereegranskat)
  • 42.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Rodionova, N. A.
    Blagoveshchensk State Pedagogical University.
    Binuclear cadmium dithiophosphate crystals: 13C, 31P, and 113Cd CP/MAS NMR studies2003Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 29, nr 5, s. 301-306Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    31P NMR signals for the terminal and bridging ligands of the complexes were differentiated. The experimental NMR spectra show 31P-111,113Cd and 113Cd-31 P spin-spin couplings only for the terminal ligands. The chemical shift anisotropy δ and the asymmetry parameter η were calculated for 31P and 113Cd NMR signals. It was found that the 31P chemical shifts for the terminal and bridging dithiophosphato groups differ in anisotropy character.

  • 43.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Larsson, Anna-Carin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Kritikos, Mikael
    Stockholm University.
    Forsling, Willis
    Polycrystalline and surface O,O′-dialkyldithiophosphate zinc(II) complexes: preparation, 31P CP/MAS NMR and single-crystal X-ray diffraction studies2001Ingår i: Inorganica Chimica Acta, ISSN 0020-1693, E-ISSN 1873-3255, Vol. 315, nr 1, s. 26-35Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dithiophosphate zinc(II) complexes with eight different O,O′-dialkyldithiophosphate ligands have been prepared in solid/liquid states and as surface complexes on a synthetic sphalerite, and studied by means of 31P NMR spectroscopy. All 31P resonances, corresponding to dithiophosphate ligands with different structural functions (i.e. terminal chelating or bridging between two metal atoms in bi- and tetranuclear complexes), have been assigned on the basis of comparative analyses of chemical shift data for solid complexes, their melts and chloroform solutions at various concentrations. The bridging coordination of O,O′-dialkyldithiophosphate ligands by the two neighbouring zinc(II) atoms was established in the case of zinc(II) complexes formed at the surface of the synthetic sphalerite. In addition, novel molecular and crystal structures of the binuclear O,O′-di-cyclo-hexyldithiophosphate zinc(II) complex have been resolved by single-crystal X-ray diffraction data analysis, and useful correlations with 31P NMR data for this complex were obtained.

  • 44.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Bredjuk, O.A.
    Blagoveshchensk State Pedagogical University.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    ESR and Solid-State Natural Abundance 13 C CP/MAS NMR Study of Crystalline Alkyl (R=C 2 H 5 , i- C 3 H 7 , i- C 4 H 9 , s- C 4 H 9 , C 5 H 11 ) Xanthate Copper(II) and Thallium(I) Complexes.2005Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 31, nr 1, s. 45-50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Crystalline thallium(I) alkylxanthate complexes [Tl{S(S)COR}]n (R = C2H5, i-C3H7, i-C 4H9, s-C4H9, and C5H 11) and isotope-substituted heteropolynuclear Cu(II)Tl(I) complexes [63(65)CuTl6(S2COR)8] (R= i-C 4H9 and C5H11) were obtained and studied by ESR and high-resolution solid-state 13C CP/MAS NMR spectroscopy. According to the 13C NMR data, polynuclear thallium(I) complexes contain structurally equivalent alkylxanthate ligands. The ESR study revealed the Jahn-Teller dynamic effect in Cu(II)Tl(I) complexes; the nuclei of six Tl atoms are involved in the hyperfine interaction

  • 45.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Bredyuk, O. A.
    Blagoveshchensk State Pedagogical University.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Copper(II) and Nickel(II) Alkylxanthate complexes (R = C2H5, i-C3H7, i-C4H9, s-C4H9, and C5H11): EPR and solid-state 13C CP/MAS NMR Studies2004Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 30, nr 7, s. 480-485Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Alkylxanthate complexes of the general formula [M{S(S)COR}2] (M = Ni, 63Cu, and 65Cu; R = C2H5, i-C3H7, i-C4H9, s-C4H9, and C5H11) were synthesized and studied by EPR and high-resolution solid-state 13C CP/MAS NMR. In the copper(II) complexes stabilized in the matrix of nickel(II) compounds, square planar chromophores [CuS4] are characterized by rhombic distortion (EPR data). Experimental EPR spectra were simulated at the second order of perturbation theory. Nickel(II) complexes were characterized by 13C NMR spectra. In all cases, the -OC(S)S- groups were found to exhibit intramolecular structural equivalence.

  • 46.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Bredyuk, O. A.
    Russian Adademy of Sciences.
    Gerasimenko, A. V.
    Russian Adademy of Sciences.
    Lutsenko, I. A.
    Russian Adademy of Sciences.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Structures of polynuclear thallium(I) and copper(II)-thallium(I) complexes with dialkyldithiocarbamates: 13C and 15N CP/MAS NMR, EPR, and X-ray diffraction studies2006Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 32, nr 5, s. 339-349Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A comparative study of polynuclear thallium complexes with dialkyldithiocarbamates [Tl2{S2CNR2}2]n (R = CH3, i-C3H7, C4H9, and i-C4H9; R2 = (CH2)6) was performed by solid-state 13C and 15N CP/MAS NMR spectroscopy. The dithiocarbamate groups were found to be structurally equivalent in the complexes studied. An increase in the positive inductive effect of alkyl substituents at the N atom increased 15N chemical shifts as a result of a combination of positive inductive effect of the alkyl substituents and the mesomeric effect of=NC(S)S-groups. The first representative of thallium(I) complexes with a cyclic dithiocarbamate ligand [Tl2{S2CN(CH2)6}2]n was obtained. Its molecular structure was determined from X-ray diffraction data. The β-form of the isotope-substituted complex [63/65CuTl2{S2CN(CH2)6}4] was obtained and examined by EPR spectroscopy. The EPR spectra were modeled at the second order of the perturbation theory. The spin density at the thallium atoms was calculated and its distribution over the AOs of thallium was determined.

  • 47.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Kritikos, M.
    Rodina, T. A.
    Lutsenko, I. A.
    The structural reorganization of bis-(diethyldithiocarbamato)-pyridine-zinc(II) and -copper(II) in the process of clathration with CCl4 molecules on ESR, solid state natural abundance C-13 and N-15CP/MAS NMR spectroscopy and single crystal X-ray diffraction data1999Ingår i: Doklady Akademii Nauk, ISSN 0869-5652, Vol. 366, nr 5, s. 643-648Artikel i tidskrift (Refereegranskat)
  • 48.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Kritikos, M.
    Arrhenius Laboratory, University of Stockholm.
    Rodina, T.A.
    Amur State University, Blagoveshchensk, Russian Federation.
    Lutsenko, I.A.
    Amur Institute of Integrated Research, Far East Division, Russian Academy of Sciences.
    Structural reorganization of bis(diethyldithiocarbamato)pyridinezinc(II) and bis(diethyldithiocarbamato)pyridinecopper(II) upon clathrate formation with CCl4 by EPR, high-resolution solid-state 13C and 15N NMR, and X-ray crystallography1999Ingår i: Doklady. Chemistry, ISSN 0012-5008, E-ISSN 1608-3113, Vol. 366, nr 4-6, s. 142-147Artikel i tidskrift (Refereegranskat)
  • 49.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Novikova, E. V.
    Blagoveshchensk State Pedagogical University.
    Adducts of diethyldithiocarbamate complexes of zinc(II) and copper(II) with piperidine [M(Pip)(Edtc)2] and their solvated forms [M(Pip)(Edtc)2] · L (L = C6H6, C5H5N, C4H9NO): synthesis, EPR and solid-state (13C, 15N) CP/MAS NMR studies2001Ingår i: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 27, nr 3, s. 158-166Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Crystal adducts of diethyldithiocarbamate complexes of zinc(II) and copper(II) with piperidine (Pip) were synthesized, and their solvated forms with the outer-sphere molecules of benzene, pyridine (Py), and morpholine (Mf) were obtained. Adducts with composition [M(Pip)(Edtc)2] · L (L = Py, Mf) were shown to be able, in principle, to give solvated isomers [M(L)(Edtc)2] · Pip with the Pip molecule arranged in the outer sphere. The composition, structure, and properties of the obtained adducts were studied by EPR, high-resolution solid-state 13C, 15N NMR spectroscopy. Solvation of all three adducts with Pip, Mf, and Py was found to result in a substantial increase in the contribution of the trigonal-bipyramidal component to the geometry of a copper coordination pentahedron. In addition, for adducts with Mf and Py, a structural unification of two isomeric forms was observed at the molecular level to yield a qualitatively new (rather than intermediate) state. It was shown that in all solvated forms of the copper(II) adducts, the metal polyhedron is mainly a trigonal bipyramid, while the square-pyramidal contribution is insignificant. Results of (13C, 15N) NMR studies revealed a structural inequivalence of the Edtc-ligands in the zinc adducts under investigation.

  • 50.
    Ivanov, Alexander V.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Forsling, Willis
    Kritikos, M.
    Antzutkin, Oleg
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Larsson, Anna-Carin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Zhukov, F. A.
    Yusupov, Z. F.
    Structural organization of zinc, nickel(II), and copper(II) O,O '-dicyclohexyl phosphorodithioate complexes as probed by X-ray diffraction, EPR, and solid-state high-resolution C-13 and P-31 NMR2000Ingår i: Doklady. Chemistry, ISSN 0012-5008, E-ISSN 1608-3113, Vol. 375, nr 1-3, s. 236-241Artikel i tidskrift (Refereegranskat)
1234 1 - 50 av 163
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