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111.
Toni Andersson Susanna Holappa Vladimir Aseyev Heikki Tenhu 《Journal of polymer science. Part A, Polymer chemistry》2003,41(13):1904-1914
The interactions between oppositely charged polyelectrolytes were studied in saline aqueous solutions as functions of the temperature and the salt and polymer concentrations. The polyanion was a diblock copolymer composed of a poly(ethylene oxide) block and a poly(sodium methacrylate) block. Two polycations were used, the homopolymer poly(methacryl oxyethyl trimethylammonium chloride) and its poly(ethylene oxide)‐grafted analogue. By dynamic light scattering and turbidity measurements, it was observed that the salt concentration, temperature, and counterion size had a significant effect on the formation of the polymer complexes in aqueous solutions. At a fixed salt concentration and a fixed temperature, it was possible to form completely soluble complexes of an ionic polymer in aqueous solutions between poly(ethylene oxide)‐grafted poly(methacryl oxyethyl trimethylammonium chloride)and the polyanion with a poly(ethylene oxide) block at a 1:1 anion/cation ratio. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1904–1914, 2003 相似文献
112.
Ly HV Moilanen J Tuononen HM Parvez M Roesler R 《Chemical communications (Cambridge, England)》2011,47(29):8391-8393
Ruthenium and iron sandwich complexes incorporating cyclopentadienyl analogs with CB(2)N(2)(-) skeletons were characterized. Electrochemical measurements supported by computational studies revealed that in combination with larger metal ions such as Ru the CB(2)N(2)(-) ligand can be more electron-rich than its organic counterpart. 相似文献
113.
Bogdan A Molina MJ Tenhu H Loerting T 《Physical chemistry chemical physics : PCCP》2011,13(44):19704-19706
Atmospheric aerosol droplets containing NH(4)(+) and SO(4)(2-) ions are precursors of cirrus ice clouds. However, the low-temperature phase transformation of such droplets is not understood yet. Here we show for the first time that micrometre-scaled (NH(4))(2)SO(4)/H(2)O droplets produce one freezing event but three melting events which are the melting of (i) pure ice, (ii) eutectic ice/(NH(4))(2)SO(4), and (iii) eutectic ice/(NH(4))(3)H(SO(4))(2). We also find that the melting of ice/(NH(4))(3)H(SO(4))(2) consists of two eutectic melting events, presumably ice/letovicite-II and ice/letovicite-III. 相似文献
114.
Heikki Hakkarainen Nageswari Shanmugalingam 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(16):5525-5543
We study relations between the variational Sobolev 1-capacity and versions of variational BV-capacity in a complete metric space equipped with a doubling measure and supporting a weak (1,1)-Poincaré inequality. We prove the equality of 1-modulus and the continuous 1-capacity, extending the known results for 1<p<∞ to also cover the more geometric case p=1. Then we give alternative definitions for variational BV-capacities and obtain equivalence results between them. Finally we study relations between total 1-capacity and versions of BV-capacity. 相似文献
115.
Konu J Chivers T Tuononen HM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(42):11844-11856
The metathetical reactions of a) [Li(tmeda)]2[(S)C(PPh2S)2] (Li2? 3 c ) with CuCl2 and b) [Li(tmeda)]2[(SPh2P)2CSSC(PPh2S)2] (Li2? 4 c ) with two equivalents of CuCl both afford the binuclear CuI complex {Cu2[(SPh2P)2CSSC(PPh2S)2]} ( 5 c ). The elongated (C)S? S(C) bond (ca. 2.54 and 2.72 Å) of the dianionic ligand observed in the solid‐state structure of 5 c indicate the presence of diradical character as supported by theoretical analyses. The treatment of [Li(tmeda)]2[(SPh2P)2CSeSeC(PPh2S)2] (Li2? 4 b ) and Li2? 4 c with AgOSO2CF3 produce the analogous AgI derivatives, {Ag2[(SPh2P)2CEEC(PPh2S)2]} ( 6 b , E=Se; 6 c , E=S), respectively. The diselenide complex 6 b exhibits notably weaker Ag? Se(C) bonds than the corresponding contacts in the CuI congeners, and the 31P NMR data suggest a possible isomerization in solution. In contrast to the metathesis observed for CuI and AgI reagents, the reactions of Li2? 4 b and Li2? 4 c with Au(CO)Cl involve a redox process in which the dimeric dichalcogenide ligands are reduced to the corresponding monomeric dianions, [(E)C(PPh2S)2]2? ( 3 b , E=Se; 3 c , E=S), and one of the gold centers is oxidized to generate the mixed‐valent AuI/AuIII complexes, {Au[(E)C(PPh2S)2]}2 ( 7 b , E=Se; 7 c , E=S), with relatively strong aurophilic AuI???AuIII interactions. The new compounds 5 c , 6 b , c and 7 b , c are characterized in solution by NMR spectroscopy and in the solid state by X‐ray crystallography ( 5 c , 6 b , 7 b and 7 c ) and by Raman spectroscopy ( 5 c and 6 c ). The UV‐visible spectra of coinage metal complexes of the type 5 , 6 and 7 are discussed in the light of results from theoretical analyses using time‐dependent density functional theory. 相似文献
116.
Fractional Brownian motion can be represented as an integral of a deterministic kernel w.r.t. an ordinary Brownian motion either on infinite or compact interval. In previous literature fractional Lévy processes are defined by integrating the infinite interval kernel w.r.t. a general Lévy process. In this article we define fractional Lévy processes using the com pact interval representation. We prove that the fractional Lévy processes presented via different integral transformations have the same finite dimensional distributions if and only if they are fractional Brownian motions. Also, we present relations between different fractional Lévy processes and analyze the properties of such processes. A financial example is introduced as well. 相似文献
117.
We introduce a generalization of D-spaces, which we call linearly D-spaces. The following results are obtained for a T1-space X.
- – X is linearly Lindelöf if, and only if, X is a linearly D-space of countable extent.
- – X is linearly D provided that X is submetaLindelöf.
- – X is linearly D provided that X is the union of finitely many linearly D-subspaces.
- – X is compact provided that X is countably compact and X is the union of countably many linearly D-subspaces.
Keywords: D-space; SubmetaLindelöf; Linearly Lindelöf; Countably compact 相似文献
118.
The termination detection problem of a distributed computation has gained considerable interest recently. In this paper two symmetric solutions to this problem are presented in the special case, where the distributed computation is performed by a ring of processes. We shall discuss the problem in terms of processes communicating via shared variables instead of messages. 相似文献
119.
Heikki Mannila 《Annals of Pure and Applied Logic》1983,25(3):301-305
Makowsky and Shelah have defined the concept of (λ, μ)*-compactness of a logic. This notion is shown to be equivalent to the topological (λ, μ)-compactness of the model spaces of the logic. Combining this characterization with a theorem of Alexandroff and Urysohn gives a result about (λ, μ)*-compactness as a corollary. 相似文献
120.
Fiber fractions from processing of barley in production and conservation of a biologic control agent
Tapani Tuomi Mari Heino Heikki Rosenqvist Katrina Nordström Simo Laakso 《Applied biochemistry and biotechnology》2001,94(2):135-145
Carriers are frequently used to overcome problems associated with microbial survival in soil after inoculation. Moreover,
the use of carriers can prolong the shelf lives and lessen dusting of both biofungicides and biologic fertilizers. This study
investigated the suitability of barley-based fiber fractions as growth media and immobilization matrices in the cultivation
of a Streptomyces griseoviridis biologic control agent, as well as for the conservation of obtained biomass in dehydrated hydrogel capsules. The second main
ingredient in all the examined carrier matrices was alginate. The aim was to find a hydrogel formulation suited for a production
process in which all individual steps, including cultivation of the organism; downstream processing; and formulation, storage,
and application of the product (i.e., biologic control agent), are carried out in the hydrogel matrix. Of the tested fractions,
brewer’s spent grain was the best choice, when considering the price vs the nutrient contents as well as the storage time
and ease of processing of the crude and the finished products. It seems that cereal fibers can be replenished with cereal
fractions less rich in fiber but having a higher content of utilizable nutrients and, hence, better suited for the production
of biomass. A high content of water-insoluble fiber favorably influenced the appearance as well as the applicability of the
products. 相似文献