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In our previous work we were able to prove that gelled bicontinuous microemulsions are a novel type of orthogonal self-assembled system. The study at hand aims at complementing our previous work by answering the question of whether gelled lyotropic liquid crystals are also orthogonal self-assembled systems. For this purpose we studied the same system, namely, water-n-decane/12-hydroxyoctadecanoic acid (12-HOA)-n-decyl tetraoxyethylene glycol ether (C10E4). The phase boundaries of the nongelled and the gelled lyotropic liquid crystals were determined visually and with (2)H NMR spectroscopy. Oscillating shear measurements revealed that the absolute values of the storage and loss moduli of the gelled liquid crystalline (LC) phases do not differ very much from those of the binary organogel. While both the phase behavior and the rheological properties of the LC phases support the hypothesis that gelled lyotropic liquid crystals are orthogonal self-assembled systems, freeze-fracture electron microscopy (FFEM) seems to indicate an influence of the gel network on the structure of the Lα phase and vice versa.

By the introduction of a generalized magnetic vector potential, which contains the contributions of both the magnetic and electric parts, and the use of the Ampere's law within the quasistatic approximation as the state equation, the partial differential equations for governing the electromagnetic properties of superconductors as well as the surrounding coolant were established and numerically discretized by resorting to the finite-element technique and finite-difference scheme, respectively, in the spatial and temporal domain. In conjunction with an analytic method to calculate the magnetic field generated by permanent magnet, we compiled a numerical tool for performing an intricate study of the mutual effect among the superconducting constituents in a superconducting levitation system with translational symmetry. Taking a superconducting unit with three constituents inside as a practice, we simulated the electromagnetic responses of this unit while moving in the nonuniform magnetic field generated by permanent magnet guideway and, identified the influences of the mutual effect on the levitation force as well as on the distributions of the magnetic flux density, the supercurrent density, and the levitation force density by comparing to an envisaged reference, one constituent was simulated with all the rest absent to remove the mutual effect. The insights attained by the present study, mostly being inaccessible from the experiments, are aimed to provide useful implications for the design of a superconducting levitation system for the transit and analogous purposes, which usually employ multiple superconductors to achieve the desired capability.

The first-order metal-insulator transition (MIT) in magnetite has been known for a long time but is still controversial in its nature. In this study, well-defined magnetite nanocrystals (NCs) with controllable size, shape and terminated surface are first employed to elucidate this important issue, and new discoveries such as a highly suppressed phase transition temperature are identified by monitoring the variable-temperature electric resistance and infrared spectroscopy. Significantly, by carefully comparing the infrared vibrational bands of the as-prepared magnetite NCs with octahedral and cubic shapes, respectively, we found that these two forms of magnetite NCs exhibited different transmittance changes and frequency shifts of the infrared characteristics, presumably due to the differences in the lattice distortions on the corresponding {001} and {111} terminal surfaces. This result produced evidence in support of the charge ordering of Fe atoms along the low dimensionality at octahedral B sites undergoing the MIT. Taken together, infrared identification was proposed to be an available characterization strategy for MIT, which can reflect more information on the elusive lattice distortion of crystallographic structure or exposed surfaces.

A conceptual structure of a 10-MW salient-pole wind turbine generator with race-track-shaped high-temperature superconductor (HTS) field coils is proposed, and a novel electrical design method for the salient-pole wind turbine HTS synchronous generators (WTHGs) is developed. In addition, the novel electrical design method derivation is introduced in detail according to the design process. In addition, the influence of some main machine parameters, e.g., pole pitch, stator outer diameter, magnetic flux density in the stator teeth, and electric loading, on HTS generator performance is clarified, and the optimal parameters are obtained thereby. Moreover, the optimized performance parameters of a 10-MW WTHG are compared with the conventional wind turbine generators with copper field windings. Finally, it is indicated that large-scale WTHGs have a higher power density, lighter weight, and higher efficiency than the conventional counterparts.Index Terms-Electrical design method, high-temperature superconductor (HTS) field coil, machine parameter, optimized design, salient-pole HTS generator. 1051-8223

As a demountable structure, the structure with design for deconstruction (DfD) is considered as a key contribution on the promotion of current construction sustainability by directly reusing valuable components from old structures. As a preliminary study, this paper investigated the cyclic behavior of bolted joints consisting of three reinforced concrete blocks bolted by steel bolts under axial compressive, focusing on the damage and failure modes, resistance mechanism and stiffness development of the joints. Results showed that the number of steel bolts, the tightening process of the bolts and concrete compressive strength all had a significant effect on the overall performance and capacity of the joints. The failure mode of most of tested joints was considered as fracture of stirrups and steel bolts in the tested joints. According to the investigation of this study, several recommendations on the design of the joints were provided.

The purpose is to study the influence of virtual entrepreneurship practice on entrepreneurial talent cultivation and innovation and entrepreneurship education in higher education institutions. First, a questionnaire is designed from three aspects: entrepreneurial awareness, entrepreneurial psychological quality, and entrepreneurial knowledge structure. Afterward, the questionnaire is issued to 200 students from a college in Shaanxi province, and SPSS 25 is chosen to analyze and characterize the virtual entrepreneurship practice education and the innovation and entrepreneurship education in higher education institutions. The results show that among all the subjects, nearly 20% of them do not understand entrepreneurship, nearly 85% of them concern about the risk of entrepreneurship, and nearly 70% of them take a negative attitude toward entrepreneurial failure. Meanwhile, the subjects have not formed an independent view on entrepreneurship, the subjects’ basic entrepreneurial quality is poor, their entrepreneurship awareness is weak, and their entrepreneurial psychological quality is poor. The subjects lack entrepreneurial quality rather than entrepreneurial knowledge. Finally, some suggestions are put forward on education on virtual entrepreneurship practice in higher education institutions from four aspects: improving the external environment of entrepreneurship, improving the entrepreneurship curriculum in higher education institutions, improving the teaching staff, and developing the practice bases for entrepreneurship education. The results provide some ideas about promoting the comprehensive reform of talent training mode in higher education institutions.

The present work is focused on multi-attribute group decision-making (MAGDM) problems with the uncertain 2-tuple linguistic information (ULI 2-tuple ) based on new aggregation operators which can capture interrelationships of attributes by a parameter vector P. To begin with, we present some new uncertain 2-tuple linguistic MM aggregation (UL 2-tuple -MM) operators to handle MAGDM problems with ULI 2-tuple , including the uncertain 2-tuple linguistic Muirhead mean (UL 2-tuple -MM) operator, uncertain 2-tuple linguistic weighted Muirhead mean (UL 2-tuple -WMM) operator. In addition, we extend UL 2-tuple -WMM operator to a new aggregation operator named extended uncertain 2-tuple linguistic weighted Muirhead mean (EUL 2-tuple -WMM) operators in order to handle some decision-making problems with ULI 2-tuple whose attribute values are expressed in ULI 2-tuple and attribute weights are also 2-tuple linguistic information. Whilst, the some properties of these new aggregation operators are obtained and some special cases are discussed. Moreover, we propose a new method to solve the MAGDM problems with ULI 2-tuple . Finally, a numerical example is given to show the validity of the proposed method and the advantages of proposed method are also analysed.