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Writing as one of essential skills in English learning is attached more and more importance. English writing involves not only the application of lexicon and grammar, but also the construction of the text and the expression of the thought. For Chinese EFL learners, the common problem in English writing is that they tend to apply the Chinese thinking pattern and organizational pattern to wording, phrasing and even the text construction. In other words, Chinese EFL learners lack English thought pattern. Based on that, the researcher puts forward the "tree analysis diagram" to help Chinese EFL learners acquire the English thinking pattern. The current research compares the differences between the Chinese thinking pattern and the English thinking pattern; analyzes the effect of these differences on English writing and verifies the effectiveness of the "tree analysis diagram" in helping Chinese EFL learners developing the English thinking pattern and improving the quality of English writing by an experiment. The results of the research showed that the Chinese thinking pattern influences students' English writing and the main problem is that the organizational pattern and the logic of the writing are not clear. After the application of the "tree analysis diagram", the results showed that "tree analysis diagram" to some extent can help Chinese EFL learners avoid the influence of the Chinese thinking pattern; improve the ability of composing English writings with the English thinking pattern; develop the habit of conceiving and writing in English; arouse the interest for English writing and eventually improve the quality of English writing.

One SSY type equipment clamp serviced in a 500 kV station was found to be cracked. In this paper, the crcaked cause and mechanism is investigated by means of macroscopic morphology observation, fracture surface morphology observation, X-ray digital detection, metallographic observation. The results indicated that the main reason for the fracture of the equipment clamp this time is that the terminal board is a cast part, which contains a large number of casting defects such as porosity and shrinkage, resulting in a decrease in its effective cross-sectional area and load-bearing capacity. In addition, insufficient modification treatment of the terminal board led to insufficient toughness due to needle or rod-shaped eutectic silicon in the organization. Finally, under the combined action of dynamic load and self weight caused by the swinging of the wire in the wind, the terminal board was brittle fractured along the bolt hole with obvious stress concentration effect.

In order to improve the functionality of cellulosic materials research and development of high performance soluble materials. Therefore, the Fe3O4/CMS composite membrane was prepared by using carboxymethyl salix powder (CMS) and Fe3O4 as raw materials, 1-propenyl-3-methylimidazolium chloride and dimethyl sulfoxide as dissolution system. The effects of swelling time, swelling temperature, pH and ionic strength on the swelling performance of Fe3O4/CMS composite membranes and the swelling kinetics of the composite membranes were studied. The structure of the composite membrane was characterized by SEM, FT-IR, XRD and TG. The results showed that the swelling degree reached 5.54 g·g−1, when the swelling time was 45 min, the swelling temperature was 65°C, the pH was 5 and the ionic strength was 0.08 mol·L−1. The initial phase of dissolution of the composite membrane fits well with the Fickian diffusion model, and the whole dissolution process belongs to the Schott model, indicating that the main role of the dissolution process is the diffusion of water molecules, while the composite membrane can be preserved for a long time at high temperature, which provides sustainability for the composite membrane. The characterization results showed that the surface of Fe3O4/CMS composite film was rough with small grooves. The O-H effect was enhanced and the Fe-O absorption peak appeared at 600 cm−1, indicating that Fe3O4 had been successfully loaded onto the cellulose membrane. The Fe3O4/CMS composite membrane belonged to cellulose type II structure, meanwhile, the composite membrane had good thermal stability. [ABSTRACT FROM AUTHOR]

We proposed a coherent radiation scheme based on double-stimulated Raman scattering (SRS) induced cascaded four-wave mixing (FWM) in a mixed methanol–ethanol solution. The SRS of methanol has two characteristic vibrational peaks, which are attributed to the symmetric stretching vibration of –CH3 and the antisymmetric stretching vibration of –CH3. The addition of ethanol enhances the antisymmetric stretching vibration mode, and intensities of two peaks were similar when the volume ratio of methanol to ethanol was 7.5:2.5. Resonant amplification of the two SRS signals is achieved by refocusing the scattered light, and the stronger self-focusing effect not only converges the two beams but also generates a plasma-enhanced SRS process, realizing cascaded FWM. The frequency difference Δ ω between two FWM beams matches the frequency difference Δ Ω between the vibrational energy levels of the symmetric and antisymmetric stretching vibrations, and the stimulated excitation enhances FWM signals. The output coherent radiation light is a large broadband ranging from 592 to 668 nm and 721 to 797 nm, with a wavelength interval of about 3 nm. The intensity of light radiated at different wavelengths is not the same, with the strongest light at the center of the wavelength (630 and 759 nm). This technique has the potential to contribute to the development of a multi-wavelength cascaded Raman laser. [ABSTRACT FROM AUTHOR]

Dynamic structural color based on tunable optical resonance plays a key role in applications including encryption visualization, camouflage and colorimetric sensing. However, the current design requires either complex growth processes of the high-quality tunable materials or complicated circuit designs. This work makes a humidity-swelling hydrogel layer for metal–insulator–metal (MIM) structure in the dynamic multi-color display. Here, polyvinyl alcohol (PVA) hydrogel structure is patterned through grayscale e-beam lithography and the controlled PVA thickness leads the programmable reflective resonance covering the entire visible range. By varying the ambient humidity between 9.8 and 90.1% RH, the reflective resonance of the structure is tailored across a wavelength range over 100 nm. Our materials platform of humidity-sensitive hydrogel resist presents a novel approach of the stepwise and reversible optical tunability for photonic devices.

With the continuous evolution of the mobile communication generation, human society has gradually convert from the era of “Mobile Internet” to the era of “Internet of Everything”. 5G networks will break the limitations of the traditional mobile communication industry and reshape the social development model. 5G will realize a new round of information revolution. As a new generation of mobile communication technology, 5G could provide basic communication guarantee for current innovative applications, such as the Internet of Things, autonomous vehicles and industrial Internet, and meet the explosive growth of data traffic and massive device connections. Security is a core for the comprehensive promotion of 5G networks. This paper analyzes the security risks in 5G networks and clarifies its security requirements. Finally, it proposes the corresponding security architecture, which will provide reference for the subsequent development of 5G network security technology.

The phase‐field method was employed to simulate the effects of pores on grain growth in the indium gallium zinc oxide (IGZO) targets during conventional and two‐stage sintering (TSS). The findings indicated that the TSS method effectively suppressed the rapid growth of grains. With an increase in porosity and a more prominent pore size, the rate of grain growth accelerated, resulting in the formation of coarser grains. Subsequently, IGZO targets were fabricated using the molding‐cold isostatic pressing (CIP) and TSS methods. The densification activation energies of IGZO green compacts were calculated to be 510 and 370 kJ/mol for CIP at 180 and 250 MPa, respectively, utilizing the main sintering curve (MSC). Additionally, by optimizing the TSS process, a highly dense IGZO target with a relative density of 99.53%, a resistivity of 4.3 mΩ/cm, and an average grain size of 8.59 µm was successfully achieved. [ABSTRACT FROM AUTHOR]

The rapid development of the Industrial Internet of Things (IIoT) has brought enormous opportunities to the industrial environment, but has also posed significant challenges to network security, especially physical layer security, which is crucial for the reliable transmission of messages among interconnected devices and sensors. Focusing on enhancing the physical layer security in IIoT communication, this paper proposes a mechanism for the Spatial Secrecy Outage Probability (SSOP) to ensure the secure transmission of data. The SSOP algorithm assumes that the location of legitimate devices is known, while the eavesdropper devices have a random distribution of locations, forming the SSOP model related to the device locations from the perspective of insecure regions (ISRs) and secure regions (SRs), and the closed-form expression for its upper bound is derived. Subsequently, under the constraint of the SSOP conditions, we establish an optimization model with the objective of system throughput maximization based on the Spatial Secrecy Outage Probability (SRM-SSOP). By optimizing the transmission rate of legitimate channels or controlling the transmission power, the maximization of the system throughput can be achieved, thus reducing the consumption of communication resources. Through sophisticated modeling and simulation in MATLAB, we verified the accuracy of the definition and derived the upper bound of the SSOP. The experimental results also show that the SSOP algorithm gradually converges to a specific value as the number of antenna elements increases. In addition, we observed that, when the receiver device is aligned with the normal direction of the transmit antenna array, the SSOP reaches a minimum value. This performance is crucial for understanding and optimizing the security performance of IIoT communication systems. [ABSTRACT FROM AUTHOR]