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191.
The experiments of metal Cd extraction were carried out three times at oil phase/aqueous phase (O/A)=1 and pH 2.2 by using 1.3 mol/L di(2-ethylhexyl)phosphoric acid (DEHPA) as the agent,with an extraction rate of 99.5%.Experiments on metal Co extraction were done three times at O/A=0.5 and pH 4.7 by using 0.4 mol/L Cyanex 272 as the agent,with an extraction rate of 99.2%.By using equilibrium data and massive calculations to analyze and predict the interaction among the extraction systems,this paper came out with the polynomials of the empirical model as well as their parameter values for the equilibrium concentration of the above two extraction loops.  相似文献   
192.
Characteristics of supersonic flow are examined with specific regard to nano-particle thin-film coating. Effects of shockwaves, nozzle geometry, chamber pressure, and substrate location were studied computationally. Shockwaves are minimized to reduce fluctuations in flow properties at the discontinuities across diamond shock structures. Nozzle geometry was adjusted to ensure optimal expansion (i.e., P exit = P ambient), where shock formation was significantly reduced and flow kinetic energy maximized. When the ambient pressure was reduced from 1 to 0.01316 bar, the nozzle’s diverging angle must be increased to yield the optimum condition of minimized adversed effects. Beyond some critical distance, substrate location did not seem to be a sensitive parameter on flow characteristics when P amb = 0.01316 bar; however, overly close proximity to the nozzle exit caused flow disturbances inside the nozzle, thereby adversely affecting coating gas flow.  相似文献   
193.
194.
A thermodynamic mathematical model, describing behavior of Pb, Zn, and As during reducing slag cleaning in the Vanyukov furnace has been developed. Using a developed model, the influence of different factors, such as temperature, oxygen partial pressure, the ratio of the formed phases on the behavior of impurities, was analyzed. It was found that arsenic can significantly move to the bottom phase, and zinc can be significantly vaporized under conditions in the Vanyukov furnace.  相似文献   
195.
Collagen and collagen-based scaffolds offer distinct advantages when selected as biomaterials for use across a broad spectrum of regenerative medicine applications. However, relatively poor mechanical properties are often perceived to limit their usefulness for orthopedic applications. These problems can be overcome through enhanced crosslinking mechanisms or through the addition of a second, stiffer phase such as hydroxyapatite, thus allowing tailored composite scaffolds to meet specific tissue requirements. This overview will highlight the current state of the art of these scaffolds, and consider the exciting prospects and future directions of collagen-based technologies for orthopedic regenerative medicine.  相似文献   
196.
197.
In the current paper, different kinds of silicon wastes during the production of SoG-Si were summarized and the beneficial analyses, such as financial value, energy value, CO2 emissions, and efficiency and energy payback time, were briefly discussed for the recycling of SoG-Si wastes. Possible technologies to recycle and purify SoG-Si wastes were reviewed: such as filtration, sedimentation, solidification control, electromagnetic separation, plasma oxidation, centrifugation, and high temperature remelting process, et al.  相似文献   
198.
199.
Cation-promoted supramolecular assembly of cobalt(II) and ruthenium(II) tetra-15-crown-5-phthalocyaninates is comparatively studied using the electronic absorption and infrared spectroscopy. The effects of the nature of the receptor and substrate on the architecture of the supramolecular aggregates formed are discovered. By contrast to Cu(II), Zn(II), and Ni(II) tetra-15-crown-5-phthalocyaninates, Co(II) and Ru(II) complexes are found to demonstrate sodium-potassium selectivity determined by the peculiarities of supramolecular structures formed upon the interaction with the cations.  相似文献   
200.
Measuring the spatial distribution of locations of many entities (trees, atoms, economic activities, etc.), and, more precisely, the deviations from purely random configurations, is a powerful method to unravel their underlying interactions. Several coefficients have been developed in the past to quantify the possible deviations. It is important to quantify the variances of the coefficients for random distributions, to ascertain the statistical significance of an empirical deviation. By lack of a proper analytical expression, the significance is usually obtained by simulating many random configurations by Monte Carlo simulations. In the present paper, we present an exact analytical expression for the variance of several spatial coefficients for random distributions, and we rigorously show that these distributions asymptotically follow a Normal law. These two results eliminate the need for cumbersome Monte Carlo simulations. They also allow to understand qualitatively the main factors that may change the variance: number of sites, spatial inhomogeneity, etc.  相似文献   
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