The atmospheric pressure glow discharge (APGD) is more promising in industrial applications compared with glow discharges in a gas other than air or in low-pressure air, which needs an expensive vacuum system. In this paper, the APGD and dielectric barrier discharge (DBD) are generated in atmospheric air using a power-frequency voltage source, and the transition from DBD to APGD is achieved by varying the electrode arrangement. The differences between their discharge characteristics are shown by measurement of their electrical discharge parameters and observation of light-emission phenomena. The effects of APGD and DBD on polytetrafluoroethylene (PTFE) surface modification are studied. The surface properties are characterized by contact angle measurement, x-ray photoelectron spectroscopy and scanning electron microscopy. It is found that the APGD and DBD treatments modify the PTFE surface in both morphology and composition. APGD is more effective in PTFE surface modification than DBD as it can modify the surface more uniformly, implant more oxygen atoms into the surface and make the contact angle decline to a lower level. The experimental results are discussed.

In search of a magnetic oxide, which is insensitive to oxygen at interfaces and thus appropriate as an electrode layer for tunneling junction applications, we prepared thin films of CoFeHfO by reactive DC-magnetron sputtering technique and investigated the relation between structural and magnetic properties. The results suggest that the films consist of two disorded phases, a Co(Fe)-rich and a HfO-rich. It was found that the degree of film homogeneity and thus the magnetic nature depends on preparation conditions such as film thickness and deposition rate. A second magnetic phase with a high saturation field, which is present in thicker films, could therefore be reduced by decreasing the film thickness. Consequently, the thinnest film (10 nm) is nearly single phased and exhibits an excellent uniaxial anisotropy with a coercive field Hc of 16 Oe along the easy axis. Additionally, thermomagnetic measurements were carried out to understand annealing-induced effects. A clear improvement with increased saturation magnetisation (Ms = 695 emu/cm 3 ) and decreased Hc was observed, which can be attributed to structural relaxation and phase separation caused by annealing.

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In recent years, deep learning has been widely used in emotion recognition, but the models and algorithms in practical applications still have much room for improvement. With the development of graph convolutional neural networks, new ideas for emotional recognition based on EEG have arisen. In this paper, we propose a novel deep learning model-based emotion recognition method. First, the EEG signal is spatially filtered by using the common spatial pattern (CSP), and the filtered signal is converted into a time–frequency map by continuous wavelet transform (CWT). This is used as the input data of the network; then the feature extraction and classification are performed by the deep learning model. We called this model CNN-BiLSTM-MHSA, which consists of a convolutional neural network (CNN), bi-directional long and short-term memory network (BiLSTM), and multi-head self-attention (MHSA). This network is capable of learning the time series and spatial information of EEG emotion signals in depth, smoothing EEG signals and extracting deep features with CNN, learning emotion information of future and past time series with BiLSTM, and improving recognition accuracy with MHSA by reassigning weights to emotion features. Finally, we conducted experiments on the DEAP dataset for sentiment classification, and the experimental results showed that the method has better results than the existing classification. The accuracy of high and low valence, arousal, dominance, and liking state recognition is 98.10%, and the accuracy of four classifications of high and low valence-arousal recognition is 89.33%.

The origin of the martensitic transition in the magnetic shape memory alloy Ni-Mn-Ga has been widely discussed. While several studies suggest it is electronically driven, the adaptive martensite model reproduced the peculiar nonharmonic lattice modulation. We used femtosecond spectroscopy to probe the temperature and doping dependence of collective modes, and scanning tunneling microscopy revealed the corresponding static modulations. We show that the martensitic phase can be described by a complex charge-density wave tuned by magnetic ordering and strong electron-lattice coupling. DOI: 10.1103/PhysRevLett.115.076402 PACS numbers: 71.45.Lr, 78.47.-p, 81.30.Kf, 81.70.Fy Magnetic shape memory alloys present a new type of multifunctional materials, which display strong coupling between the magnetic and structural degrees of freedom. The ferromagnetic Ni-Mn-Ga alloy serves as a prototype system, displaying a giant 12% magnetic-field-induced strain in its low-temperature (T) martensitic phase (M phase) [1,2]. Since in Ni-Mn-Ga the M-phase transition can be tuned far above the room temperature by changing stoichiometry or doping [3,4], this alloy is of special technological interest [1,2,5].The rich phase diagram of Ni 2þxþy Mn 1−x Ga 1−y is characterized by a complex sequence of phase transitions. In its high-T (austenite) phase, Ni-Mn-Ga has a cubic L2 1 Heusler structure. At the M-phase transition temperature T M , the lattice undergoes a transformation, which can be described by a periodic shuffling of (011) planes along the ½011 direction [6]. Depending on the stoichiometry and the residual stress, the resulting low-T M phase is commonly found to have either tetragonal or orthorhombic symmetry, with a modulation period of ten (10M) or 14 (14M) atomic layers [6,7], respectively. For specific stoichiometries, e.g., Ni 2þx Mn 1−x Ga with x ≲ 0.1, a premartensitic phase (PM phase) is observed above T M [3] with the transition temperature T PM up to 50 K above T M [3,8]. In the PM phase, the lattice displays a harmonic threefold modulation with the wave vector q PM ¼ q max ð 1 3 ; 1 3 ; 0Þ. Inelastic neutron scattering studies of the high-T cubic phase [9] showed a dramatic softening of the TA-2 phonon branch at q PM , indicative of a Kohn anomaly. These observations [9][10][11][12], together with the observed opening of a pseudogap at T PM [8,13], suggest an electronic instability within the Peierls scenario to be driving the PM-phase transition. The observation of a phase mode in the 10M phase [14] also suggested the electronic instability. In fact, the electronic band structure studies [11,15,16] revealed the possible Fermi surface nesting conditions for all of the observed structural modulations. However, for the case of the 14M martensite, it was argued that the modulated phase can be constructed from nonmodulated martensitic unit cells [17,18]. This adaptive martensite scenario [17][18][19] recently received considerable attention.To determine which theory gives a more appropriate physical picture of the pha...