Investigation on High Temperature Mechanical Behaviors of TiC-γ′ Reinforced Ni Composite

Wenqiang Hu,Zhenying Huang,Qun Yu,Yuanbo Wang,Yidan Jiao,Yang Zhou,Hongxiang Zhai 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

A duplex TiC and γ′-Ni3(Al,Ti) reinforced nickel composite was fabricated through hot-press sintering a 30 vol% Ti2AlC–Nimixtures followed by thermal treatment method. Detailed microstructural detection was performed by adopting the routeof high-resolution transmission electron microscopy. In situ generated submicron TiC particulate and nanosized L12-γ′were homogeneously distributed in a fcc γ-Ni matrix. The high temperature tensile and compression behaviors of the TiC-γ′/Ni composites were evaluated in the temperature range of 25–800 °C. The results indicated that ultimate tensile andcompression properties exhibited the dependence of temperatures. The tensile properties of the composite determined at600 °C was 945 MPa, decreasing by 28.1% and 23.0% for elongation, compared to those of measured at room temperature(UTS = 1305 MPa, elongation = 5.35%). However, the yield strength exhibited the temperature independent until to 600 °C. The yield strength of the TiC-γ′/Ni composite are comparable with conventional superalloy under 600 °C, proving that TiCand γ′ particles constitute efficient reinforcements for Ni matrix according to thermal expansion dislocations strengthening,load-transfer and coherent strengthening mechanisms. The monotonic temperature dependence of yield strength at600–800 °C indicates that plastic deformation of TiC-γ′/Ni composite follows the thermally activated mechanism. TheTiC-γ′/Ni composite exhibited superior mechanical properties both at room and high temperatures, which can be ascribedto the synergistic strengthening effect in term of dislocation density, Orowan, coherent and atomic ordering strengtheningmechanisms. The present work reveals the deformation behaviors of in situ TiC-γ′/Ni composite from room to high temperatures,which is critical to predict the failure and thereby optimize the microstructure to further enhance the high temperatureproperties of TiC-γ′/Ni composite.

Penipyrols A–B and peniamidones A–D from the mangrove derived Penicillium solitum GWQ-143

Wenqiang Guo,Xianglan Kong,Tianjiao Zhu,Qian Qun Gu,Dehai Li 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.8

Chemical investigation the extract of Penicillium solitum GWQ-143 led to yield four new compounds penipyrols A–B (1–2) and peniamidones A–B (3–4), together with peniamidones C–D (5–6), which had been previously described as synthetic intermediates, not obtained from natural resource. The structures of those new compounds were established through extensive spectroscopic analysis. Compounds 1–6 exhibited great radical scavenging activities against DPPH with IC50 values ranged from 4.7 to 15.0 lM.

Fuzzy Dynamic Sliding Mode Controller Design for Uncertain Nonlinear Markovian Jump Systems

Wenqiang Ji,Yujian An,Heting Zhang 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.7

This paper investigates the problem of sliding mode control (SMC) for a class of uncertain nonlinearMarkovian jump systems through T-S fuzzy models. By adopting some convexification techniques, new results onstochastic stability analysis of the sliding motion are attained. Then two new SMC design approaches are proposedto force the closed-loop system states onto the sliding surface in finite time. Finally, two simulation examples areshown to verify the effectiveness of the proposed approaches.

Effect of the scanning speed of laser cladding on microstructure and mechanical properties of WC/Ni composite coatings

Wenqiang Sun,Deqiang Zhang,Xiang Chen,Keyan Wang,Jiqing Zhang,Yunjie Jia 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.2

Cold work dies (of Cr12MoV) surface of the WC/Ni composite coating prepared by laser cladding can be used to quickly repair worn areas of dies. The composition, hardness, fracture morphology, microstructure, and shear strength of the coating were characterized by microhardness tester, universal tensile testing machine, XRD, EDS, and SEM. The results show that the main phase of the coating is composed are M 23 C 6 , FeNi 3 , Cr 7 C 3 , WC, W 2 C, Cr 2 B, Fe 2 B, and W 2 B. The change of scanning speed only changes the diffraction peak, but has little effect on the internal structure and strengthening mechanism of the coating. With the decrease of scanning speed, the powder deposition density per unit time increases, and a large number of pores and unmelted particles are mixed in the coating, which weakens the bonding strength between the coating and the substrate, and the fracture mechanism of the coating changes from quasi-cleavage fracture to brittle fracture.

Chinese EFL Learners’ Use of SubjunctiveMarkers in Writing

Wenqiang Chen 한국중원언어학회 2019 언어학연구 Vol.0 No.50

The paper aims to investigate some aspects of subjunctive mood in English and Chinese and examine how Chinese EFL learners perceive them through collecting 60 compositions. In this paper the right subjunctive markers (S-markers) refer to the past tense verbal forms in the subordinate clause, and the past tense modality form in the main clause, which excludes the incorrect S-markers: the present tense either in the subordinate or in the main clause, or in both, and the absence modal verbs in main clause. The findings of the survey reveal that their accuracy rate of S-markers is rather low. I mainly ascribe the high incorrect rates to the following factors: the discrepancy between tense and time in English, a different paradigm of expressing future time, tense and aspect denoting the degree of certainty of the utterances, the complicated modality system in the main clause, the past tense in if-conditionals, and the negative transfer from Chinese subjunctive mood, which lacks inflectional verbal forms.

Experimental Study of Shear Strength Features of Regenerated Rock Mass compacted and consolidated by Broken Soft Rocks

Wenqiang Ma,Tongxu Wang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.4

Rock mass composed of Broken Soft Rocks (BSR) under confined compression is widely distributed in geotechnical and underground engineering. To reveal the influence law of rock grain gradation and compression ratio on the shear strength properties of Regenerated Rock Mass Structure (RRMS) formed by confined compression of BSR, first, a series of compression tests of BSR with different grain gradation and compression ratios were carried out with homemade compression cylinders, through which the compression behavior of BSR was gained. In addition, the achieved Cylindrical RRMS (CRRMS) after compression was used for shear tests. Second, shear strength parameters of the CRRMS were obtained through shear tests under changing shear angle. It turns out that the CRRMS of smaller grain gradation has a better compaction degree and smoother surface. Nevertheless, the CRRMS of larger grain gradation, in contrast, has obvious gaps and a rough surface. During the compression process, the BSR of smaller grain gradation requires larger axial compression force, and the BSR of mixed grain gradations, which contain smaller grain gradation, has a better compaction effect than others. The internal friction angle of CRRMS increases with the growth in rock grain gradation, and the incremental rate of mixed grain gradations is less than those of the others. The change trend of cohesion is contrary to the internal friction angle, which decreases with the increase in grain gradation. With the homogeneous increase in the compression ratio, the internal friction angle decreases gradually, while the cohesion is contrary to the internal friction angle.

Unity Without Uniformity, Run the World with Peace

Wenqiang Fan 한국콘텐츠학회 2012 ICCC International Digital Design Invitation Exhib Vol.8 No.1

Deep Learning Assisted Differential Cryptanalysis for the Lightweight Cipher SIMON

( Wenqiang Tian ),( Bin Hu ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.2

SIMON and SPECK are two families of lightweight block ciphers that have excellent performance on hardware and software platforms. At CRYPTO 2019, Gohr first introduces the differential cryptanalysis based deep learning on round-reduced SPECK32/64, and finally reduces the remaining security of 11-round SPECK32/64 to roughly 38 bits. In this paper, we are committed to evaluating the safety of SIMON cipher under the neural differential cryptanalysis. We firstly prove theoretically that SIMON is a non-Markov cipher, which means that the results based on conventional differential cryptanalysis may be inaccurate. Then we train a residual neural network to get the 7-, 8-, 9-round neural distinguishers for SIMON32/64. To prove the effectiveness for our distinguishers, we perform the distinguishing attack and key-recovery attack against 15-round SIMON32/64. The results show that the real ciphertexts can be distinguished from random ciphertexts with a probability close to 1 only by 28.7 chosen-plaintext pairs. For the key-recovery attack, the correct key was recovered with a success rate of 23%, and the data complexity and computation complexity are as low as 28 and 220.1 respectively. All the results are better than the existing literature. Furthermore, we briefly discussed the effect of different residual network structures on the training results of neural distinguishers. It is hoped that our findings will provide some reference for future research.

Characteristics and Optimization of New Combined Magnetic Pole Negative-Salient Permanent Magnet Motor

Wang Wenqiang,Shi Liwei,Qiao Zhiwei,Zhu Yingjie,Ding Hongshan 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

With a wide speed range, high overload capacity and preventing permanent magnet demagnetization, negative-salient permanent magnet motors have a wide range of applications in the feld of electric vehicles. In view of the multiple operating conditions of the electric vehicle drive motor, this paper proposes a new type of combined magnetic pole negative-salient permanent magnet motor considering the driving conditions. Firstly, the optimization parameters of the motors are determined according to the analysis of the mathematical model. The design parameters are layered by the comprehensive sensitivity analysis, and the response surface Box-Behnken Design method and multi-objective genetic algorithm-II are used for optimization. Then, the electromagnetic performance of the proposed motor and the traditional interior permanent magnet motors are compared and analyzed through the fnite element simulation. Finally, a prototype is manufactured and the rationality of the proposed motor structure is verifed by experiments.

汉语国际教育中传统文化传播之反思

高文强(Gao Wenqiang) 동아인문학회 2012 동아인문학 Vol.22 No.-

The paper introspected three questions on the transmission of traditional culture in Chinese international education today: what to teach, who will teach and how to teach. We think that the most important question of these questions is what to teach. Now the transmission of traditional culture in Chinese international education lacked to refine and spread the core value of traditional culture. It is an important reason to cause foreigners to puzzle about and misunderstanding Chinese traditional culture. Just this question caused the questions of who will teach and how to teach. We agree that the answers to solve these questions should include three aspects: firstly, we should refine the core value of traditional culture so that foreigner can understand what the Chinese traditional culture is. Secondly, we should build a Chinese teachers team who have knowledge of many aspects and not only linguistics. Thirdly, we should improve the mode of transmission of traditional culture and pay attention to objective introduce. We believe that the transmission of traditional culture in Chinese international education will be more and more a wide range so long as we can introspect and improve continuously.