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Although Pinus sibirica and Pinus koraiensis are resistant to cold or low temperatures in the cold temperate regions of the northern hemisphere, the former has a stronger cold resistance. Research has been limited to the comparison of physiological responses of the two species to cold stress. In this study, 5-year-old seedlings of P. sibirica and P. koraiensis were subjected to six temperature treatments, [20 °C (control), 0 °C, − 20 °C, − 40 °C, − 60 °C, and − 80 °C], under different stress periods (6, 12, 24, and 48 h). The results showed that differences in each physiological index were significant between P. sibirica and P. koraiensis, except for the permeability of cell membranes, reactive oxygen species, proline and soluble proteins. An ANOVA test indicated that there were extreme differences among the temperatures for each index, stress time and temperature × time for most indices. All indices showed a similar trend for P. sibirica and P. koraiensis with decreasing temperature or the extension of stress time. Soluble sugars and proline increased at 0 to − 20 °C and then remained unchanged with temperature decline. Other indices showed an increase from 20 to − 20 °C, stable from − 20 to − 40 °C and a decrease from − 40 to − 80 °C. All the indices increased and then declined along with the prolonged cold stress time, except for the control. From 0 to − 40 °C, the permeability of cell membranes, relative conductivity, reactive oxygen species and malonaldehyde of P. koraiensis seedlings were higher than in P. sibirica, but superoxide dismutase, peroxidase, catalase activity and soluble sugars, proline, and soluble proteins content emerged as opposite. This study compared the physiological mechanism responses to cold stress between P. sibirica and P. koraiensis to provide the basis for the introduction, distribution, and genetic improvement of these coniferous species. [ABSTRACT FROM AUTHOR]

To avoid using toxic solvents, weak basic anion exchange resin with aromatic amine groups was prepared by grafting 4-vinyl pyridine onto polystyrene microspheres through simultaneous radiation grafting method. In batch adsorption experiments toward Re(VII) which was selected to simulate Tc, the adsorption efficiency maximized when the concentration of HNO was set at 0.02 M. Using reductive eluents SnCl it was found a method to efficiently regenerated resin at low acidity. For adsorption toward Tc, the results matched well with Re, which indicates that the prepared exchangers will have wide applications in the future to remove Tc from spent nuclear fuel. [ABSTRACT FROM AUTHOR]

A unified framework on distributed estimations in-network using incremental subgradient (IS) methods is introduced. The IS methods meet the requirement of the asynchronously processing, which are efficient solvers developed recently focusing on separable non-differentiable convex optimization problems. The main contribution of this paper is to formalize distributed estimators as equivalent separable convex optimization problems, where general skills and several specific cases on signal estimations are presented. Analytical and simulation results show that the IS framework can solve general nonlinear estimation problems in-network, and achieve comparable performances as the centralized estimators. [ABSTRACT FROM AUTHOR]

new approach to the optimal adaptive filtering is proposed in this paper. In this approach, a polynomial prediction model is used to describe the time-variant/invariant impulse response coefficients of an identified system. When the polynomial prediction model is viewed as the state equations of the identified impulse response coefficients and the relationships between the inputs and outputs of the system are regarded as the measurements of the states, our adaptive filtering can be achieved in the framework of the Kalman filter. It is understood that Kalman filter is optimal in the sense of the MAP (maximum a posteriori), ML (most likelihood) and MMSE (minimum mean square error) under the linear and Gaussian white noise conditions. As a result, our algorithm is also optimal in the statistical senses as Kalman filter does, provided that the impulse response coefficients can be modeled by a polynomial. Not only do the analytical results of the algorithm but also the simulation results show that our algorithm outperforms the traditional known algorithms. [ABSTRACT FROM AUTHOR]

Depolymerization of nylon 6 to produce ε-caprolactam using an environmentally friendly heteropoly acid catalyst was studied at temperatures between 553 and 603 K in water. The products of depolymerization were analyzed qualitatively and quantitatively by means of mass spectrometry and high-performance liquid chromatography. The results showed that the depolymerized product was mainly ε-caprolactam with a little 6-aminocaproic acid and oligomers. The phosphotungstic heteropoly acid used as a catalyst can improve the hydrolysis rate and yield of ε-caprolactam. The optimum hydrolysis conditions for ε-caprolactam yield were as follows: phosphotungstic heteropoly acid content, 3%; reaction temperature, 573 K; and reaction time, 85 min. Under these conditions, the yield of ε-caprolactam was 77.96%. In the temperature range 553-603 K, the activation energy of 3% phosphotungstic heteropoly acid-catalyzed depolymerization was evaluated as 77.38 kJ/mol, which is lower than the 86.64 kJ/mol value for no catalyst. [ABSTRACT FROM AUTHOR]

A real-time image-tracking algorithm is proposed, which gives small weights to pixels farther from the object center and uses the quantized image gray scales as a template. It identifies the target’s location by the mean-shift iteration method and arrives at the target’s scale by using image feature recognition. It improves the kernel-based algorithm in tracking scale-changing targets. A decimation method is proposed to track large-sized targets and real-time experimental results verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]