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31.
A modelling project involved system dynamics simulation of chronic cardiac disease in Bulgaria, examining the dynamic behaviour of a cardiac drug molecule in the market. The system dynamics model was calibrated using market data sourced from the Bulgarian National Health Care Fund, the Bulgarian Generic Pharmaceutical Association and a market research firm. The main results of the study showed that the timing of access to market was a critical driver in reducing prices and providing wider, as well as more affordable, access for patients to medicinal therapy. Our findings indicate that healthcare authorities may obtain savings while, at the same time, they may provide conditions for more patients to be treated depending on the timing of access to market of new generic drugs.  相似文献   
32.
An automated control system for epitaxial facilities was developed based on the Advantech Co. software and hardware.  相似文献   
33.
Kinetics and Catalysis - The catalytic properties of supported Mn/carrier catalysts (carriers: Al2O3, SiO2, SiO2–Al2O3) in the ozone-assisted oxidation of volatile organic compounds (using...  相似文献   
34.
Kinetics and Catalysis - The catalytic performance of a bimetallic RhIn/SiO2 catalyst was studied in the liquid-phase hydrogenation of nitrobenzene. The formation of intermetallic Rh1In1...  相似文献   
35.
Effect of the ion composition of aqueous solutions on the oxygen absorption kinetics in a system constituted by a gas (air) and a liquid (aqueous solution) in the presence of microencapsulated quartz particles activating the mass transfer in the liquid phase was studied. It was found that ions with positive hydration cause a substantial decrease in the O2 mass-transfer enhancement factor, whereas ions with negative hydration lead to its increase under the same conditions. It is shown that the effect of ions on the rate of oxygen absorption by aqueous electrolyte solutions can be prognosticated on the basis of data on the influence of these ions on the structure and viscosity of water. The results of the study can serve as a basis for varying the rate of heterogeneous reactions in gas-liquid systems, whose rate is limited by the mass transfer of oxygen into aqueous media, by purposeful control over their ion composition.  相似文献   
36.
Complexes formed by interaction of E(C6F5)3 (E = B, Al, Ga, In) with excess of acetonitrile (AN) were structurally characterized. Quantum chemical computations indicate that for Al(C6F5)3 and In(C6F5)3 the formation of a complex of 1:2 composition is more advantageous than for B(C6F5)3 and Ga(C6F5)3, in line with experimental observations. Formation of the solvate [Al(C6F5)3 · 2AN] · AN is in agreement with predicted thermodynamic instability of [Al(C6F5)3 · 3AN]. Tensimetry study of B(C6F5)3 · CH3CN reveals its stability in the solid state up to 197 °C. With the temperature increase, the complex undergoes irreversible thermal decomposition with pentafluorobenzene formation.  相似文献   
37.
A scheme of nepheline processing by a hydrochemical method was technically justified. In this process, silica is transformed into calcium hydrosilicate under autoclave conditions at a low concentration of caustic alkali. This allows the process at high heat regeneration and low steam flow for evaporation of a solution. A joint effect of temperature, leaching time, and concentration of caustic alkali solution was examined on an alumina recovery. Experiments were designed using a combined rotatable design of a second order.  相似文献   
38.
The acidic and hydrogenating of Pt/SO42−-ZrO2-Al2O3 samples containing from 18.8 to 67.8 wt % Al2O3 as a support constituent were studied by the IR spectroscopy of adsorbed CO and pyridine, and the model reactions of n-heptane and cyclohexane isomerization on these catalysts were examined. The total catalyst activity in the conversion of n-heptane decreased with the concentration of Al2O3; this manifested itself in an increase in the temperature of 50% n-heptane conversion from 112 to 266°C and in an increase in the selectivity of isomerization to 94.2%. In this case, the maximum yield of isoheptanes was 47.1 wt %, which was reached on a sample whose support contained 67.8 wt % Al2O3. A maximum yield (69.6 wt %) and selectivity (93.7%) for methylcyclopentane formation from cyclohexane were also reached on the above catalyst sample. This can be explained by lower concentrations of Lewis and Br?nsted acid sites in the Pt/SO42−-ZrO2-Al2O3 system, as compared with those in Pt/SO42−-ZrO2. The experimental results allowed us to make a preliminary conclusion that the Pt/SO42−-ZrO2-Al2O3 catalyst whose support contains 67.8 wt % Al2O3 is promising for use in the selective hydroisomerization of benzene-containing gasoline fractions in the thermodynamically favorable process temperature range of 250–300°C.  相似文献   
39.
The quasi-diamagnetism effect that manifests itself in the negative magnetic susceptibility observed in weak magnetic fields during cooling of samples below some critical temperature has been revealed in Ni48Co2Mn35In15 Heusler alloys. The effect has been attributed to a strong nonequilibrium of the system due to the presence of magnetic and structural disorders and exchange anisotropy.  相似文献   
40.
We present the results of the first directional point-contact spectroscopy experiments in high-quality MgB2 single crystals. Because of the directionality of the current injection into the samples, the application of a magnetic field allowed us to separate the contributions of the sigma and pi bands to the total conductance of our point contacts. By using this technique, we were able to obtain the temperature dependency of each gap independent of the other. The consequent, strong reduction of the error on the value of the gap amplitude as a function of temperature allows a stricter test of the predictions of the two-band model for MgB2.  相似文献   
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