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From Nowick's self-induced ordering theory, we develop a new configurational entropy relation to describe the non-Arrhenius temperature (T)-dependent relaxation in disordered systems. Both the loss of configurational entropy and the coupling interaction among relaxing units (RUs) are explicitly introduced in this relation; thus, this relation offers a novel connection, which differs from the Adam-Gibbs (A-G) entropy relation, between kinetics and thermodynamics, and this relation generalizes several well-known currently used relations. The present relation can provide direct and more accurate estimates of (i) the intrinsic activation enthalpy, (ii) the T-evolution of the configurational entropy loss of the system, and (iii) the self-induced ordering temperature Tc, which characterizes the coupling interaction among RUs. The application of the theory to experimental data for the relaxation time in typical organic liquids demonstrates the validity of the theory. [ABSTRACT FROM AUTHOR]

Chemical investigation of Paxillus involutus lead to the isolation of a new coumarin derivative coumarin-pi (1), and three known compounds (2-4). The structure of the new compound was elucidated by interpretation of 1D and 2D NMR data. Compound 1 possesses a rare benzofuranylcoumarin skeleton. The isolated compounds were evaluated for antioxidant activities and coumarin-pi (1) exhibited significant activity with IC50 value of 16.3 μg/mL. [ABSTRACT FROM AUTHOR]

By measuring the dependences of the temperature-dependent primary ('alpha') dielectric relaxation time behavior on the temperature scanning rate for the glass-forming glycerol, we study the scaling of hysteresis at the glass transition in glycerol. Based on the Vogel-Fulcher-Tammann (VFT) expression and the Angell's fragility concept, notable correlations of the systematic kinetic fragility, and of the hysteresis effect in the vitrification/fusion 'alpha'-relaxation process of glycerol, with the temperature scanning rate, were reasonably analyzed and discussed. It was observed that the kinetic fragility m and the apparent glass-transition temperature hysteresis width ΔTga, respectively, scaled the temperature scanning rate q as m ≈ αmq-γ and ΔTga ≈ A0 + αqβ, at which the exponents, γ and β, were suggested to be characteristic of the resistance to the structure change or fragility change of the system during the glass transition. The observed scaling laws are quite similar to the scaling power law for the thermal hysteresis in the first-order phase transition (FOPT) of solids, providing a significant insight into the hysteresis effect in the glass transition of the glass-forming liquids. [ABSTRACT FROM AUTHOR]

The traditional double long baselines interferometer (DLBI) requires the baselines to be strictly co-prime for locating algorithm. Besides, t is sensitive to the phase error and the performance becomes seriously bad with higher fuzzy number. To solve the problems, an improved direction-finding algorithm with double baselines rotating interferometer (DBRI) was proposed. In the DBRI, two baselines were designed with arbitrary length and palstance to rotate in the opposite direction. The locating was carried out according to the phase difference gotten from the improved direction-finding algorithm, obtaining better location precision with high fuzzy number and better robust to the phase discrimination error. Finally, the effectiveness and validity of the proposed algorithm were verified by computer simulations. [ABSTRACT FROM AUTHOR]

This study investigated the effects of glycinin on the growth, intestinal oxidative status, tight junction components, cytokines and apoptosis signalling factors of fish. The results showed that an 80 g/kg diet of glycinin exposure for 42 d caused poor growth performance and depressed intestinal growth and function of juvenile Jian carp (Cyprinus carpio var. Jian). Meanwhile, dietary glycinin exposure induced increases in lipid peroxidation and protein oxidation; it caused reductions in superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) activities; and it increased MnSOD, CuZnSOD, GPx1b and GPx4a mRNA levels, suggesting an adaptive mechanism against stress in the intestines of fish. However, dietary glycinin exposure decreased both the activity and mRNA levels of nine isoforms of glutathione-S-transferase (GST) (α, μ, π, ρ, θ, κ, mGST1, mGST2 and mGST3), indicating toxicity to this enzyme activity and corresponding isoform gene expressions. In addition, glycinin exposure caused partial disruption of intestinal cell–cell tight junction components, disturbances of cytokines and induced apoptosis signalling in the distal intestines>mid intestines>proximal intestines of fish. Glycinin exposure also disturbed the mRNA levels of intestinal-related signalling factors Nrf2, Keap1a, Keap1b, eleven isoforms of protein kinase C and target of rapamycin/4E-BP. Interestingly, glutamine was observed to partially block those negative influences. In conclusion, this study indicates that dietary glycinin exposure causes intestinal oxidative damage and disruption of intestinal physical barriers and functions and reduces fish growth, but glutamine can reverse those negative effects in fish. This study provides some information on the mechanism of glycinin-induced negative effects. [ABSTRACT FROM PUBLISHER]

ABSTRACT Using dynamic mechanical analysis (DMA), we investigated the in situ crystallization kinetics of non-nucleated and nucleating-agent-treated isotactic polypropylene ( iPP) under continuous oscillatory shear during the entire crystallization process, and then compared the DMA results with those measured using differential scanning calorimetry under conventional quiescent crystallization. Our analyses, based on the Avrami equation, show that continuous oscillatory shear accelerated crystallization of non-nucleated iPP, but interfered with crystallization for nucleating-agent-treated iPP. Our results indicate that, for the present nucleating agent, its accelerating effect on crystallization cannot coexist with the accelerating effect of shear on crystallization. We attributed this difference to the disruptive effect of shear on growth and the different nucleation models of non-nucleated and nucleating-agent-treated iPP. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41685. [ABSTRACT FROM AUTHOR]

For the purpose of testing the Equivalence Principle (EP) to unprecedented accuracy, experiment based on satellite in space becomes increasingly popular because of the environmental limitation on the earth. We transferred the theoretical test of EP to measurement of the rate of fall of test masses in engineering. For the ongoing development of the satellite test of the Equivalence Principle ( STEP), drag-free satellite and super-accurate accelerometer was key technology. We presented design and analysis of the drag-free control system and the differential accelerometers for STEP to ensure the test of EP to one part of 1018 . [ABSTRACT FROM AUTHOR]

Taking account of earth oblateness and atmospheric drag, this article established the relative orbital dynamics for electromagnetic formation flying. The model of electromagnetic force is derived by the dipole approximation of the coils, and the relative orbital dynamics of EMFF is derived by Hill equation. Utilizing the linearization of electromagnetic force between any two satellites, atmospheric drag and earth oblateness, the linear relative orbital dynamics is presented. The results indicate that the linear relative orbital dynamics is reasonable and feasible. Compared to the nonlinear dynamics, the error of 3 revolution is about 0.05 m ~ 5 m, which is resulted from the linearization of electromagnetic force. [ABSTRACT FROM AUTHOR]

A input shaping control algorithm is provided for vibration suppression of rigid-flexible coupling systems with large overall motion. For the sake of describing actual dynamics of those rigid-flexible coupling systems, a first-order approximation dynamic model was presented. The second-order coupling terms was included in the longitudinal deformation. The modal characteristics of the flexible beam in rigid-flexible coupling system was different from that of the beams in structural dynamics in large overall motion. Considering the differences, a robust multiple-mode input shaper was designed. Simulation results show that the presented control strategy suppresses the beam's vibration successfully during attitude maneuver. [ABSTRACT FROM AUTHOR]

The development status and tendency of drag-flee satellite formation flying are analyzed, and its dynamic modelling and system control are discussed. The application foreground and related key technologies to be solved are addressed, which provide a basis for space environment observation and space weather detection in the future. [ABSTRACT FROM AUTHOR]

An algorithm for the autonomous and fast solution of Lambert' s problem in earth J2 perturbation environment is presented in this paper. By adopting Battion's method to solve the two-body Lambert's problem, the actual position of satellite is obtained by analytical orbital theory. By using the error between the actual position and the object position, the object position in two-body Lambert' s problem is adjusted time after time. Then the Lambert's problem in earth J2 perturbation is solved. Simulation result demonstrates that the autonomous algorithm has advantages of simple modeling, fast convergence, low computational costs and high orbit maneuver precision. The onboard computer calculating quantity can be decreased by far. [ABSTRACT FROM AUTHOR]