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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sensorless control of permanent magnet synchronous motors (PMSMs) based on the model is usually affected by changes in motor parameters. For this reason, this paper proposes a novel method based on the neutral point third harmonic back electromotive force (EMF) and a second-order generalized integrator-based frequency-locked loop (SOGI-FLL). This method is not related to any motor parameters and only requires a neutral wire. Firstly, the relationship between neutral point voltage and third harmonic back EMF is analyzed, and a new low-cost third harmonic back EMF detection circuit and sampling method is presented. A cascaded structure consisting of a limiting filter and a sliding window median filter is designed to filter out switching spike pulses and sampling noise. Then, SOGI-FLL technology is applied to extract and track the rotor position and filter out non-third harmonic signals caused by the asymmetry of the three-phase back EMFs. Finally, simulation and experimental results demonstrate that the proposed method has high static and dynamic position estimation accuracy. [ABSTRACT FROM AUTHOR]

Dengue remains a public health issue worldwide. Similar to chronic infectious diseases, stimulation of cytokine production is not enough to drive immune effector cells for effective virus clearance. One possible mechanism is the virus induces a large number of negative stimulatory cytokines inhibiting immune response. Interleukin 37 (IL-37) plays a crucial regulatory role in infection and immunity, inhibits innate and adaptive immunity as an anti-inflammatory cytokine by inhibiting proinflammatory mediators and pathways. To date, there are few studies reporting correlations between dengue fever (DF) and IL-37. In this study we found that the serum IL-37b and IL-37b-producing monocytes in patients were significantly increased in DF patients. A majority of the IL-37b produced by DF patients was produced by monocytes, not lymphocytes. Increased levels of IL-6, IL-10, and IFN-α were also found in DF patients. However, we failed to detect IL-1β, IL-17A and TNF-α in plasma, because of off-target. In our study, there was no relation between IL-6, IL-10, and IFN-α expressions and IL-37b in serum (P > 0.05). The IL-37b-producing monocytes were negatively correlated with the level of IFN-α in serum and platelet count, and positively correlated with lymphocytes percentage (P < 0.05, respectively). Additionally, serum DENV nonstructural protein 1 levels were positively correlated with monocytes percentages (P < 0.05). Our data represents findings for IL-37b expression and its potential mechanisms in DF patients’ immune response. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The three kinds of differences distinguished in Emmanuel Levinas' thinking, along with François Jullien's relevant elaborations, are utilised to distinguish three ways of contemplating interculturality: "distinction" treats different cultures as different parts of a unity, "strangeness" sees the other culture as exotic and heterogeneous, and "alterity" views the other culture as an ethical object that can never be captured by the subject. However, there are significant differences between Levinas and Jullien's philosophies. The former emphasises the priority of the other over the self, while the latter emphasises reflection of the self through the other. On the one hand, in cross-cultural communication, "the intelligible common," the ultimate purport of divergence, can balance the asymmetry between the self and the other in Levinas' thinking. On the other hand, Levinas' ethics is also a necessary complement to the idea of divergence: according to Levinas, divergence is bound to occur when the self takes on responsibility for the other. The two strands of thought need to be reconciled and practised in real life Only by returning to the simplicity and complexity of life can Levinas and Jullien's thoughts be activated. Correspondingly, cross-cultural communication based on alterity and divergence should also be expanded from mere cognitive understanding to living practices. A cross-cultural life will not only expand a subject's freedom and range of possibility but also work as a strategy to resist capitalist globalisation and its consequences of homogenisation and uniformisation. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Let x = (x',x") with x'∈ ℝk and x" ∈ ℝN-k and Ω be a x'-symmetric and bounded domain in ℝN (N ≥ 2). We show that if 0 ≤a ≤ k−2, then there exists a positive constant C > 0 such that for all x'-symmetric function u ∈ C∞0 (Ω) with ∫Ω∇u(x)N−ax'−adx ≤ 1, the following uniform inequality holds where . Furthermore, βa can not be replaced by any greater number. As the application, we obtain some weighted Trudinger–Moser inequalities for x-symmetric function on Grushin space. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, namely [Zn2(phen)2(DHTA)]·2H2O (1) and [Zn2(PHDI)2(DHTA)]·2H2O (2) (phen = 1,10-Phenanthroline, PHDI = 1,10-Phenanthroline-5,6- dione, DHTA = 2,5-dihydroxyterephthalic acid) have been synthesized under hydrothermal conditions. The structures have been determined by single crystal X-ray diffraction, thermal gravimetric analysis, infrared spectrum and luminescent properties. The X-ray diffraction analysis revealed the coordination modes of Zn(II) centers from complexes (1) and (2) are different. In (1), there are unusual five coordinated and six coordinated Zn(II) ions. In (2), the center is four coordinated Zn (II). Through these coordination modes of Zn centers and the π-π stacking interactions of organic ligands, the two complexes are all connected to three-dimensional supramolecular networks. The solid-state photoluminescence properties of (1) and (2) have been investigated. The emission peaks are located at 538 and 603 nm, the emissions may be attributed to the metal-to-ligand charge-transfer. The quantum-chemical calculations have been performed on ‘molecular fragments’ extracted from the crystal structure using the B3LYP method in Gaussian 09. [ABSTRACT FROM AUTHOR]

To alleviate the undesirable vibration and acoustic noise of switched reluctance motor (SRM), an asymmetric-carrier random PWM (ACRPWM) method is designed to shape the harmonic spectra for the speed control of the SRM. The ACRPWM can not only effectively spread the harmonic spectra of the voltage to a more wide frequency range, but also maintain the fixed switching frequency in the control of the converter. The shaping of the harmonic spectra can reduce the harmonic components beside the switching frequency and its integer multiples. The harmonic spread factor and total harmonic distortion are used to evaluate the performance of the ACRPWM. The ACRPWM is tested on hard and soft switching modes of the converter in the speed control of the SRM, respectively. Simulation results certify the effectiveness of the proposed ACRPWM in the shaping of the harmonic spectra for the SRM. [ABSTRACT FROM AUTHOR]

Two new metal-organic frameworks (MOFs) based on cadmium(II) ions, 1,2-benzenedicarboxylic acid (BDC), flexible ligand 1,4-bi(1H-imidazol-1-yl)butane (BIIM), coordinated water molecules, [(BIIM)(BDC)(HO)Cd] ( 1) and copper(II) ions, BIIM, coordinated water, free thiophene-2,5-dicarboxylate (TDC), free water, {[(BIIM)(HO)Cu]·(TDC)·(HO)} ( 2) are prepared and characterized by X-ray diffraction, thermal gravimetric analysis (TGA), infrared (IR) spectrum and the photoluminescence property for complex ( 1). The X-ray diffraction analysis reveals that the structures of complexes 1 and 2 are 2D structures through the C-H···π stacking interactions (for 1) and the BIIM bridging connections (for 2). The IR spectrum for 1 and 2 are presented in the paper, for 1, the strong peaks at 1399 and 1573 cm are owing to the carboxylic CO symmetry and asymmetry stretching vibrations of BDC. The features of the IR spectrum are consistent with the single crystal structures. The TGA reveal the water is the first lost material from complex, then the ligands removed, and finally the residues of these two complexes are the metal oxide. [ABSTRACT FROM AUTHOR]

This study is focused on micro-scale measurement of metal (Ca, Cl, Fe, K, Mn, Cu, Pb, and Zn) distributions in Spartina alterniflora root system. The root samples were collected in the Yangtze River intertidal zone in July 2013. Synchrotron X-ray fluorescence (XRF), computed microtomography (CMT), and X-ray absorption near-edge structure (XANES) techniques, which provide micro-meter scale analytical resolution, were applied to this study. Although it was found that the metals of interest were distributed in both epidermis and vascular tissue with the varying concentrations, the results showed that Fe plaque was mainly distributed in the root epidermis. Other metals (e.g., Cu, Mn, Pb, and Zn) were correlated with Fe in the epidermis possibly due to scavenge by Fe plaque. Relatively high metal concentrations were observed in the root hair tip. This micro-scale investigation provides insights of understanding the metal uptake and spatial distribution as well as the function of Fe plaque governing metal transport in the root system. [ABSTRACT FROM AUTHOR]

How to generate a non-zero first hyperpolarizability for a centrosymmetric molecule is a challenging question. In this paper, an external (pump) electric field is used to make a centrosymmetric benzene molecule generate a non-zero value of the electric field induced first hyperpolarizability (β). This comes from the centrosymmetry breaking of electron cloud. Two interesting rules are exhibited. (1) β is anisotropic for different directional fields ( F, i = X, Y, Z). (2) The field dependence of β is a non-monotonic function, and an optimum external electric field causes the maximum value of β. The largest first hyperpolarizability β reaches the considerable level of 3.9 × 10 a.u. under F = 330 × 10 a.u. for benzene. The external electric field effects on non-centrosymmetric edge-modified graphene ribbon HN-(3,3)ZGNR-NO was also studied in this work. The first hyperpolarizability reaches as much as 2.1 × 10 a.u. under F = 600 × 10 a.u. for HN-(3,3)ZGNR-NO. We show that the external electric field can not only create a non-zero first hyperpolarizability for centrosymmetric molecule, but also remarkably enhance the first hyperpolarizability for a non-centrosymmetric molecule. [ABSTRACT FROM AUTHOR]

A transmission electron microscopy (TEM) study was made of the interphase boundary structure between the matrix and α1 plates formed at 250 °C, 300 °C, and 350 °C in three Cu-Zn-Al alloys. The experiments showed that the α1 plates formed at each temperature studied in all of the alloys are initially free of stacking faults. This observation, confirming the results of previous investigations, shows that these plates cannot have formed by a shear mechanism. Ledges were shown to exist on the broad faces and/or at the growth edges of the α1 plates. Indirect evidence implies that the ledges are mobile and that they can migrate along different directions on the broad faces. [ABSTRACT FROM AUTHOR]

Superledges on the broad faces of bainitic ferrite plates have been observed with transmission electron microscope (TEM). The observed superledges, ranging from less than 1 to 24 nm in height, are imaged in three dimension by way of tilt operation under TEM. Also, an array of smaller superledges are observed to pile up in front of a secondary phase. Pileup of superledges in front of a barrier is indicative of the mobility of an individual superledge. The precipitation of carbide associated with bainitic ferrite is also studied. It is observed that a carbide of a wedgelike shape may exist in front of a superledge with its tip (i.e., thinner end) penetrating the austenite and its root (the other end) originating at α:γ boundary. This condition indicates that the observed carbides may nucleate at the austenite side of α:γ phase boundary and grow toward austenite matrix. [ABSTRACT FROM AUTHOR]