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91.
Silver fenocyanide as well as Silver ferricyanide are converted into silver thiocyanate by treating with thiocyanate ions, while feirocyanide ions or ferricyanide ions are formed at the same time. Silver ferrocyanide as well as silver ferricyanide are dissolved by solutions of thiocynates of higher concentrations. 相似文献
92.
I. The fact, that the blue violet colour of the microcosimic salt bead of cobalt is changed into blue by addition of Na2CO3 K2CO3, K2CO3 NA2HPO4 or NA3PO4is explained by the formation of pyrophosphate in the melt. II. K2Na2P2O7 if melted together with CoCl2 forms blue porcelaneous masses, completely soluble in water. 相似文献
93.
Ohne Zusammenfassung 相似文献
94.
Moritz Kohn 《Monatshefte für Chemie / Chemical Monthly》1935,66(1):393-405
Ohne ZusammenfassungFrühere Mitteilungen: Z. anorg. allg. Chem.49 (1906) 443; Mh. Chem.43 (1922) 373, bzw. S.-B. Akad. Wiss. Wien (II b)131 (1922) 373; Mh. Chem.44 (1923) 97, bzw. S.-B. Akad. Wiss. Wien (IIb)132 (1923) 97; Z. anorg. allg. Chem.197 (1931) 287,197 (1931), 289. 相似文献
95.
A. E. Blagov Yu. A. Dyakova M. V. Kovalchuk V. G. Kohn M. A. Marchenkova Yu. V. Pisarevskiy P. A. Prosekov 《Crystallography Reports》2016,61(3):362-370
A new approach to the study of the structural quality of crystals is proposed. It is based on the use of X-ray standing-wave method without measuring secondary processes and considers the multiwave interaction of diffraction reflections corresponding to different harmonics of the same crystallographic reflection. A theory of multiwave X-ray diffraction is developed to calculate the rocking curves in the X-ray diffraction scheme under consideration for a long-period quasi-one-dimensional crystal. This phase-sensitive method is used to study the structure of a multilayer lead stearate film on a silicon substrate. Some specific structural features are revealed for the surface layer of the thin film, which are most likely due to the tilt of the upper layer molecules with respect to the external normal to the film surface. 相似文献
96.
Weber N Pesnell A Bolikal D Zeltinger J Kohn J 《Langmuir : the ACS journal of surfaces and colloids》2007,23(6):3298-3304
The hemocompatibility of polymeric vascular implants is in part dependent on the propensity of fibrinogen to adsorb to the implant surface. Fibrinogen surface adsorption was measured in real time using a quartz crystal microbalance with dissipation monitoring (QCM-D). Six new, biodegradable tyrosine-derived polycarbonates were used as test surfaces. Stainless steel, poly(L-lactic acid), poly(D,L-lactide-co-glycolide), and poly(ethylene terephthalate) surfaces served as controls and provided a comparison of the test surfaces with those of commonly used biomaterials. Our study addressed the question regarding to which extent systematic variations in polymer structure can be used to optimize X-ray visibility and provide tunable degradation rates while generating protein-repellant surface properties that minimize fibrinogen adsorption. QCM-D revealed surface-dependent changes in fibrinogen layer thickness (2 to 37 nm), adsorbed wet mass (0.2 to 4.3 microg/cm2), and viscosity (0.001 to 0.005 kg/ms). While we did not find an overall correlation between surface air-water contact angle measurements and fibrinogen adsorption (R2 = 0.08), our data demonstrate that gradually increasing the poly(ethylene glycol) content within a subgroup of polymers having the same polymer backbone will lead to decreased fibrinogen adsorption. Within this subgroup of polymers, there was a strong correlation between decreasing air-water contact angles and decreasing fibrinogen adsorption (R2 = 0.95). We conclude that it is possible to minimize fibrinogen adsorption to tyrosine-derived polycarbonates while optimizing X-ray visibility and degradation rates. Some of the tyrosine-derived polycarbonates were identified as useful materials for the design of blood-contacting implants on the basis of their substantially lower levels of fibrinogen adsorption relative to the commonly used controls. 相似文献
97.
98.
We consider an interacting-particle algorithm which is population-based like genetic algorithms and also has a temperature parameter analogous to simulated annealing. The temperature parameter of the interacting-particle algorithm has to cool down to zero in order to achieve convergence towards global optima. The way this temperature parameter is tuned affects the performance of the search process and we implement a meta-control methodology that adapts the temperature to the observed state of the samplings. The main idea is to solve an optimal control problem where the heating/cooling rate of the temperature parameter is the control variable. The criterion of the optimal control problem consists of user defined performance measures for the probability density function of the particles’ locations including expected objective function value of the particles and the spread of the particles’ locations. Our numerical results indicate that with this control methodology the temperature fluctuates (both heating and cooling) during the progress of the algorithm to meet our performance measures. In addition our numerical comparison of the meta-control methodology with classical cooling schedules demonstrate the benefits in employing the meta-control methodology. 相似文献
99.
K. M. Podurets D. K. Pogorelyi A. A. Kaloyan E. S. Kovalenko V. G. Kohn 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2012,6(5):845-848
The synchrotron radiation used in X-ray tomography enables us to vary the recording conditions within wide limits due to the continuous spectrum and the beam’s high brightness and collimation. The possibilities of multimode X-ray tomography at the Mediana station of the Kurchatov synchrotron radiation source, including tomography and microtomography based on white and “pink” beams, imaging with the help of a monochromatic beam, and measurements via axial and refractive phase-contrast methods, are described. The presented results of the reconstruction of different objects have been obtained under different recording conditions. 相似文献
100.
V. G. Kohn 《Crystallography Reports》2006,51(6):936-940
A computer program for calculating the complex kinematic scattering parameters χ0, χh, and $\chi _{\bar h} $ of X rays, which are Fourier components of the crystal complex susceptibility, as well as some of their combinations, is presented. The values calculated by the program can be used for computer simulation of experimental results obtained by the X-ray standing-wave method. Methods for calculating these parameters on the basis of well-known tables are described in detail. For crystals of complex structure, it is necessary to know their structure and the Debye temperature or specific heat capacity in order to calculate χh and $\chi _{\bar h} $ . To calculate χ0, it is sufficient to know the chemical formula and the density of a material. 相似文献