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51.
Optimization of 2-propanol oxidation over CuMnmCo2?mO4 nanospinels was carried out by a split design method. 15-term model was proposed to fit the experimental data. The model revealed that both whole plot and subplot variables have significant effects on conversion of 2-propanol. The model predicted the interaction of subplot and whole plot variables as well as their importance. The maximum conversion of 2-propanol was observed over CuMn2O4 (x1 = 0.33, x2 = 0, x3 = 0.67) at calcination and reaction temperatures of 800 °C (z1 = 1) and 300 °C (z2 = 1), respectively. The predicted response and the response obtained from experiment for optimum conditions were 93.36 and 96, respectively.  相似文献   
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By means of conformational analysis, the spatial structure and conformational potential of the H-Tyr-Ala-Gly-Ala-Val-Val-Asn-Asp-Leu-OH molecule, which corresponds to sequence 329-337 of the subunit 2 C-terminal region of the herpes virus ribonucleotide reductase, were studied. It was shown that its spatial organization can be described by a set of 17 low-energy conformations of the backbone. The "reverse conformational problem" for this molecule was solved to enable the prediction of a series of synthetic analogues matching the set of low-energy, potentially physiologically active conformations.  相似文献   
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The peculiarities of stabilization of the excess charges in composites based on PP and dispersed metal oxides are investigated using the method of radiothermoluminescence (RTL). It is shown that introduction of fillers such as BeO and ZrO2 into PP leads to change in the intensity and temperature of realization of the β1, β, α, and α1 peaks on the RTL curves, and this can be used to predict the electroactive, dielectric and physical mechanical properties of the composites based on them.  相似文献   
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A nonequilibrium version of measuring the electromotive force during a continuous decrease in the temperature at a rate of 5–7 °C/min is used to study the thermodynamic properties of solid solutions of magnesium in aluminum. The studies show that the abrupt change in the potential of an alloy containing 20–30 mol % Mg at 370–380°C reliably correlates with the decomposition of the solid solution formed at 450°C.  相似文献   
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Structural maintenance of chromosomes (SMC) proteins interact with DNA in chromosome condensation, sister chromatid cohesion, DNA recombination, and gene dosage compensation. How individual SMC proteins and their functional domains bind DNA has not been described. We demonstrate the ability of the C-terminal domains of Saccharomyces cerevisiae SMC1 and SMC2 proteins, representing two major subfamilies with different functions, to bind DNA in an ATP-independent manner. Three levels of DNA binding specificity were observed: 1) a >100-fold preference for double-stranded versus single-stranded DNA; 2) a high affinity for DNA fragments able to form secondary structures and for synthetic cruciform DNA molecules; and 3) a strong preference for AT-rich DNA fragments of particular types. These include fragments from the scaffold-associated regions, and an alternating poly(dA-dT)-poly(dT-dA) synthetic polymer, as opposed to a variety of other polymers. Reannealing of complementary DNA strands is also promoted primarily by the C-terminal domains. Consistent with their in vitro DNA binding activity, we show that overexpression of the SMC C termini increases plasmid loss without altering viability or cell cycle progression.  相似文献   
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