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31.
32.
Jianmou Lu Yanli Huang Shunyan Ren 《International Journal of Control, Automation and Systems》2020,18(5):1250-1263
This paper investigates the general decay synchronization and general decay H∞ synchronization problems of multi-weighted coupled reaction-diffusion 相似文献
33.
Ningning Fu Jiaxing Li Ming Wang Lili Ren Youqing Luo 《International journal of molecular sciences》2020,21(22)
An obligate mutualistic relationship exists between the fungus Amylostereum areolatum and woodwasp Sirex noctilio. The fungus digests lignin in the host pine, providing essential nutrients for the growing woodwasp larvae. However, the functional properties of this symbiosis are poorly described. In this study, we identified, cloned, and characterized 14 laccase genes from A. areolatum. These genes encoded proteins of 508 to 529 amino acids and contained three typical copper-oxidase domains, necessary to confer laccase activity. Besides, we performed molecular docking and dynamics simulation of the laccase proteins in complex with lignin compounds (monomers, dimers, trimers, and tetramers). AaLac2, AaLac3, AaLac6, AaLac8, and AaLac10 were found that had low binding energies with all lignin model compounds tested and three of them could maintain stability when binding to these compounds. Among these complexes, amino acid residues ALA, GLN, LEU, PHE, PRO, and SER were commonly present. Our study reveals the molecular basis of A. areolatum laccases interacting with lignin, which is essential for understanding how the fungus provides nutrients to S. noctilio. These findings might also provide guidance for the control of S. noctilio by informing the design of enzyme mutants that could reduce the efficiency of lignin degradation. 相似文献
34.
Shuncheng Liu Kejian Wang Zhongfeng Zhang Yueqing Ren Lanlan Chen Xiaojie Sun Wenbin Liang 《Polymer Engineering and Science》2020,60(10):2640-2652
Three kinds of ethylene-octene copolymers (POE) were melt-blended with high-density polyethylene (PE-HD) in different proportions. Detailed characterizations were conducted to analyze their structural differences of POE and its effects in toughening PE-HD. The higher molecular weight POE can improve the toughness of PE-HD. 60:40 PE-HD/POE is elongated to break up to 700% while impact strength is 84.7 kJ/m2 at −30°C, which is 21-fold of PE-HD. In the brittle to ductile transition (BDT) during impact, the fracture mechanism changes from the crazing mode to the shear yield-plastic deformation mode. The BDT temperature decreases as the POE molecular weight and its content increase. The interface strength in tension is estimated to access their effects. The Boltzmann-type models were successfully extended to describe the typical S-shaped curves in BDT of notched impact strength vs POE content or temperature. The supplementary decay model is suggested for the attenuation in toughening. Transition map in impact is proposed to select the use range of composition (c ) and temperature (T ) for high toughness. The curves are converted into 3D graph of T -c -impact strength for illustrating their coupling-separate effects, and further into the contour map of impact strength in T -c space for finding their partial equivalence. 相似文献
35.
Li Wei Ren Yinghui Li Chenfang Li Zhipeng Li Maojun 《The International Journal of Advanced Manufacturing Technology》2020,106(3):921-935
The International Journal of Advanced Manufacturing Technology - The wear of micro-grinding tools less than 1 mm in diameter is crucial for achieving acceptable surface quality and accurate... 相似文献
36.
Yang Yang Yibei Zhou Juan Ren Qiaoji Zheng Kwok Ho Lam Dunmin Lin 《Journal of the European Ceramic Society》2018,38(2):557-566
Perovskite ferroelectrics possess the fascinating piezoelectric properties near a morphotropic phase boundary, attributing to a low energy barrier that the results in structural instability and easy polarization rotation. In this work, a new lead-free system of (1-x)BaTiO3-xCaHfO3 was designed, and characterized by a coexistence of ferroelectric rhombohedral-orthorhombic-tetragonal (R-O-T) phases. With the increase amount of CaHfO3 (x), a stable coexistence region of three ferroelectric phases (R-O-T) exists at 0.06 ≤ x ≤ 0.08. Both large piezoelectric coefficient (d33~400 pC/N), inverse piezoelectric coefficient (d33*~547 pm/V) and planar electromechanical coupling factor (kp~58.2%) can be achieved for the composition with x = 0.08 near the coexistence of three ferroelectric phases. Our results show that the materials with the composition located at a region where the three ferroelectric R-O-T phases coexist would have the lowest energy barrier and thus greatly promote the polarization rotation, resulting in a strong piezoelectric response. 相似文献
37.
Natural Computing - The fiber stretching process plays the key role in the process of fiber production and its effects is measured by the stretching ratio. The stretching ratio is determined by the... 相似文献
38.
39.
Wei-Cheng Tang Yi-Che Su Yun-Shan Huang Ya-Tin Yu Hsin-Lung Chen I-Ming Chu 《应用聚合物科学杂志》2019,136(39):48003
While perfluoroalkyl acids (PFAAs), also known as C8s, are used extensively in textile repellent coatings, concerns have arisen for their carcinogenicity and hazardous effects on the environment. In this study, a novel water-based, nonfluoro, and nanobrush textile repelling agent was prepared by conventional sol–gel chemistry using amorphous fumed silica and n-octyltriethoxysilane as the starting materials. Minimal interaction between the designed repelling agent and marketed water-based resins was confirmed using linear viscosity region (LVR) analysis and asymmetric-flow field-flow fractionation (AF4), suggesting the self-stratification potential of the repelling agent. More specifically, the repelling agent exhibited excellent compatibility and self-stratifying ability with a force-emulsified acrylic-based resin, affording a water contact angle of 104.3° when incorporated at 7% solid content. Performance tests carried out on thermoplastic polyurethane (TPU) revealed excellent adhesion (100/100) of a final formulation, and a significant increase in water contact angle from 80.1° to 103.8° after treatment. In addition, the fouling area after the removal of a submerged sample from a mixture of slurry, polymer, and oil decreased from 48 to 1% when the repelling agent was added. Moreover, the sludge-fouling property remained unchanged after 1000 cycles of abrasion. These findings demonstrate the potential of the described nonfluoro, nanobrush repelling agent as an environmentally safe alternative for use with commercial resins, in turn realizing a fully water-based hydrophobic coating. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48003. 相似文献
40.
Chen Yonghong Chu Zhaorong Wei Yijun Liu Xingqin Meng Guangyao 《中国稀土学报(英文版)》2006,24(3):301-301
Pr0.6-x NdxCa0.4 FeO3-δ ( x = 0.0, 0.2, 0.3, 0.4, 0.5, 0.6) were synthesized using Pechini method. A number of studies were conducted concerning composition, specific area, crystalline structure and microstructure of the samples by means of FT-IR, BET, XRD TG-DTA and SEM. The results show that all the samples with different doping amounts of Pr^3+ and Nd^3+ on A-site are fine dispersed, and mean particle size less than 100 nm. The powders have good sinterability, and the relative density is 95% after sintered at 1200 ℃ for 2 h. It is found that all specimens are entirely single phase solid solutions with orthorhombic perovskite structure, the stable perovskitetype phase is formed completely after calcination at 900 ℃. 相似文献