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111.
Theodor Heczko 《Fresenius' Journal of Analytical Chemistry》1928,75(5):183-190
Ohne Zusammenfassung 相似文献
112.
Theodor Panzer 《Fresenius' Journal of Analytical Chemistry》1910,49(11):722-723
Ohne Zusammenfassung 相似文献
113.
Theodor D. Gurkov 《Colloid and polymer science》2011,289(17-18):1905-1915
At the initial stage of surfactant adsorption (when the layer is relatively diluted), the kinetics may be dominated by factors related to the transfer of molecules through the subsurface region and onto the interface. We consider two independent physical effects: (1) diffusion through a subsurface layer with nanometer thickness, where structuring or molecular interactions can impose substantial changes on the transfer rate, as compared with the bulk diffusion and (2) hindrance to the act of adsorption itself, when the molecules hit the interface from a place directly adjacent to it. These two effects are taken into account by formulating a model which includes the balance of fluxes in the subsurface layer. This model allows one to find analytical solution for the adsorption as a function of time. Application of the theory is illustrated by analyzing experimental data for two proteins which adsorb on air/water interface. Attention is paid to the particular case when the resistance to adsorption is relatively small but is still significant as compared with the bulk diffusion. Then, the theoretical fit of the adsorption vs. time can be implemented in a specific linear scale. The overall resistance of the interfacial zone comprises additive contributions from the hindrance to the act of adsorption and from the (retarded) diffusion through the subsurface layer. They are incorporated into one physical parameter (or characteristic time), which influences the kinetics. 相似文献
114.
The paper presents a new approach for machine vibration analysis and health monitoring combining blind source separation (BSS) and change detection in source signals. So, the problem is transferred from the original space of the measurements to the space of independent sources, where the reduced number of components is going to simplify the monitoring problem while the change detection methods are going to be applied for scalar signals. The assessment of the approach on a real machine is presented in this paper. 相似文献
115.
Mark Röscher Theodor Schneller Rainer Waser 《Journal of Sol-Gel Science and Technology》2010,56(3):236-243
The impact of chemical precursor modification on the electronic properties of chemical solution deposition derived niobium
oxide thin-films has been evaluated. It has been found that the application of certain chemical modifications is mandatory
in order to obtain electrically insulating thin-films at low processing temperatures. It is emphasized that the devised optimal
way of processing for the niobium component is widely contrary to the solution based processing of potassium sodium niobate
films reported so far. Regarding the physical nature of the observed instabilities, the phase evolution of solution processed
niobium oxide films has been studied. It has been detected that the organic fraction in the precursor solution is stable up
to high temperatures and as a result, the low temperature crystalline TT-phase of niobium oxide is preserved up to unusually
high processing temperatures. The inherent structural distortion of the unit cells may present a new defect mechanism that
has to be further investigated regarding the inferior ferroelectric properties of chemical solution derived potassium sodium
niobate thin-films, which are often observed. 相似文献
116.
Theodor Pöschl 《Mathematische Zeitschrift》1921,11(1-2):89-96
Ohne Zusammenfassung 相似文献
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120.
Lindner E Schreiber R Schneller T Wegner P Mayer HA Göpel W Ziegler C 《Inorganic chemistry》1996,35(2):514-525
The reaction of two equiv of the monomeric ether-phosphine O,P ligand (MeO)(3)Si(CH(2))(3)(Ph)PCH(2)-Do [1a(T(0)()), 1b(T(0)())] {Do = CH(2)OCH(3) [1a(T(0)())], CHCH(2)CH(2)CH(2)O [1b(T(0)())]} with PdCl(2)(COD) yields the monomeric palladium(II) complexes Cl(2)Pd(P approximately O)(2) [2a(T(0)())(2)(), 2b(T(0)())(2)()]. The compounds 2a(T(0)())(2)() and 2b(T(0)())(2)() are sol-gel processed with variable amounts (y) of Si(OEt)(4) (Q(0)()) to give the polysiloxane-bound complexes 2a(T(n)())(2)()(Q(k)())(y)(), 2b(T(n)())(2)()(Q(k)())(y)() (Table 1) {P approximately O = eta(1)-P-coordinated ether-phosphine ligand; for T(n)() and Q(k)(), y = number of condensed T type (three oxygen neighbors), Q type (four oxygen neighbors) silicon atoms; n and k = number of Si-O-Si bonds; n = 0-3; k = 0-4; 2a(T(n)())(2)()(Q(k)())(y)(), 2b(T(n)())(2)()(Q(k)())(y)() = {[M]-SiO(n)()(/2)(OX)(3)(-)(n)()}(2)[SiO(k)()(/2)(OX)(4)(-)(k)()](y)(), [M] = (Cl(2)Pd)(1/2)(Ph)P(CH(2)Do)(CH(2))(3)-, X = H, Me, Et}. The complexes 2b(T(n)())(2)()(Q(k)())(y)() (y = 4, 12, 36) show high activity and selectivity in the hydrogenation of 1-hexyne and tolan. The dicationic complexes [Pd(P&arcraise;O)(2)][SbF(6)](2) [3a(T(0)())(2)(), 3b(T(0)())(2)()] are formed by reacting Cl(2)Pd(P approximately O)(2) with 2 equiv of a silver salt {P&arcraise;O = eta(2)-O&arcraise;P-coordinated ether-phosphine ligand; 3a(T(0)())(2)(), 3b(T(0)())(2)() = [M]-SiOMe(3); [M] = {[Pd(2+)](1/)(2)P(Ph)(CH(2)CH(2)OCH(3))(CH(2))(3)-}{SbF(6)} (a), {[Pd(2+)](1/)(2)P(Ph)(CH(2)CHCH(2)CH(2)CH(2)O)(CH(2))(3)-}{SbF(6)} (b)}. Their polysiloxane-bound congeners 3a(T(n)())(2)(), 3b(T(n)())(2)() {[M]-SiO(n)()(/2)(OX)(3)(-)(n)} are obtained if a volatile, reversible bound ligand like acetonitrile is employed during the sol-gel process. The bis(chelate)palladium(II) complexes 3a(T(n)())(2)(), 3b(T(n)())(2)() are catalytic active in the solvent-free CO-ethene copolymerization, producing polyketones with chain lengths comparable to those obtained with chelating diphosphine ligands. The polysiloxane-bound palladium(0) complexes 5a(T(n)())(2)()(Q(k)())(4)(), 5b(T(n)())(2)()(Q(k)())(4)() {[M]-SiO(n)()(/)(2)(OX)(3)(-)(n)}(2)[SiO(k)()(/2)(OX)(4)(-)(k)](4), [M] = [(dba)Pd](1/)(2)P(Ph)(CH(2)Do)(CH(2))(3)-} undergo an oxidative addition reaction with iodobenzene in an interphase with formation of the complexes PhPd(I)(P approximately O)(2).4SiO(2) [6a(T(n)())(2)()(Q(k)())(4)(), 6b(T(n)())(2)()(Q(k)())(4)()] {[M]-SiO(n)()(/)(2)(OX)(3)(-)(n)](2)[SiO(k)()(/2)(OX)(4)(-)(k)](4), [M] = [PhPd(I)](1/2)P(Ph)(CH(2)Do)(CH(2))(3)-}, which insert carbon monoxide into the palladium-aryl bond even in the solid state. 相似文献