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41.
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空芯光子晶体光纤因其特殊的导光机制与传统光纤相比对环境的敏感性能有很大不同,成为多种光纤传感器性能突破的新选择.光纤陀螺作为一种应用广泛的光纤亿感器在温度稳定性方面具有极高的要求.本文正是针对这种新型光纤在光纤陀螺方面的应用,设计了一种测定其温度稳定性的方案,并通过结果证明光子晶体光纤的对温度的敏感程度要小丁目前普遍用于陀螺仪光纤环绕制的保偏光纤. 相似文献
43.
Qiu-Ni Zhao Ya-Jie Zhang Zai-Hua Duan Si Wang Can Liu Ya-Dong Jiang Hui-Ling Tai 《稀有金属(英文版)》2021,(6):1459-1476
Ti3C2Tx,which is a novel two-dimensional (2D)material,has received enormous interest in the field of sensor technology due to its large surface area,excellent e... 相似文献
44.
Hui-Min Zhang Fei-Fei Qi Jun Wang Yuan-Yuan Duan Li-Li Zhao Yun-Dan Wang Tong-Cun Zhang Xing-Hua Liao 《International journal of molecular sciences》2022,23(12)
Gastric cancer (GC) is the fifth most common cancer and the third deadliest cancer in the world, and the occurrence and development of GC are influenced by epigenetics. Methyltransferase-like 3 (METTL3) is a prominent RNA n6-adenosine methyltransferase (m6A) that plays an important role in tumor growth by controlling the work of RNA. This study aimed to reveal the biological function and molecular mechanism of METTL3 in GC. The expression level of METTL3 in GC tissues and cells was detected by qPCR, Western blot and immunohistochemistry, and the expression level and prognosis of METTL3 were predicted in public databases. CCK-8, colony formation, transwell and wound healing assays were used to study the effect of METTL3 on GC cell proliferation and migration. In addition, the enrichment effect of METTL3 on DEK mRNA was detected by the RIP experiment, the m6A modification effect of METTL3 on DEK was verified by the MeRIP experiment and the mRNA half-life of DEK when METTL3 was overexpressed was detected. The dot blot assay detects m6A modification at the mRNA level. The effect of METTL3 on cell migration ability in vivo was examined by tail vein injection of luciferase-labeled cells. The experimental results showed that METTL3 was highly expressed in GC tissues and cells, and the high expression of METTL3 was associated with a poor prognosis. In addition, the m6A modification level of mRNA was higher in GC tissues and GC cell lines. Overexpression of METTL3 in MGC80-3 cells and AGS promoted cell proliferation and migration, while the knockdown of METTL3 inhibited cell proliferation and migration. The results of in vitro rescue experiments showed that the knockdown of DEK reversed the promoting effects of METTL3 on cell proliferation and migration. In vivo experiments showed that the knockdown of DEK reversed the increase in lung metastases caused by the overexpression of METTL3 in mice. Mechanistically, the results of the RIP experiment showed that METTL3 could enrich DEK mRNA, and the results of the MePIP and RNA half-life experiments indicated that METTL3 binds to the 3’UTR of DEK, participates in the m6A modification of DEK and promotes the stability of DEK mRNA. Ultimately, we concluded that METTL3 promotes GC cell proliferation and migration by stabilizing DEK mRNA expression. Therefore, METTL3 is a potential biomarker for GC prognosis and a therapeutic target. 相似文献
45.
Jiao Shi Weihua Yu Chunwei Hu Haiyan Duan Jiaxing Ji Yuanyuan Kang Kun Cai 《International journal of molecular sciences》2022,23(12)
The path of crack propagation in a graphene sheet is significant for graphene patterning via the tearing approach. In this study, we evaluate the fracture properties of pre-cracked graphene during the tearing process, with consideration of the effects of the aspect ratio, loading speed, loading direction, and ambient temperatures on the crack propagation in the monolayer sheet. Some remarkable conclusions are drawn based on the molecular dynamic simulation results, i.e., a higher loading speed may result in a complicated path of crack propagation, and the propagation of an armchair crack may be accompanied by sp carbon links at high temperatures. The reason for this is that the stronger thermal vibration reduces the load stress difference near the crack tip and, therefore, the crack tip can pass through the sp link. A crack propagates more easily along the zigzag direction than along the armchair direction. The out-of-plane tearing is more suitable than the in-plane tearing for graphene patterning. The path of crack propagation can be adjusted by changing the loading direction, e.g., a rectangular graphene ribbon can be produced by oblique tearing. This new understanding will benefit the application of graphene patterning via the tearing approach. 相似文献
46.
Silicon nitride foams with a hierarchical porous structure was formed by the combination of protein-based gelcasting,chemical vapor infiltration,and in-situ growth of silicon nitride nanowires.The porosity of the foams can be controlled at 76.3-83.8 vol%with an open porosity of 70.2—82.8 vol%.The pore size distribution was presented in three levels:<2μm(voids among grains and cross overlapping of silicon nitride nanowires(SNNWs)),10—50μm(cell windows),and>100μm(cells).The resulted compressive strength of the porous bodies at room temperature can achieve up to 18.0±1.0 MPa(porosity=76.3 vol%)while the corresponding retention rate at 800℃was 58.3%.Gas permeability value was measured to be 5.16(cm3·cm)/(cm2·s·kPa).The good strength,high permeability together with the pore structure in multiple scales enabled the foam materials for microparticle infiltration applications. 相似文献
47.
Haibo Zeng Guotao Duan Yue Li Shikuan Yang Xiaoxia Xu Weiping Cai 《Advanced functional materials》2010,20(4):561-572
High concentrations of defects are introduced into nanoscale ZnO through non‐equilibrium processes and resultant blue emissions are comprehensively analyzed, focusing on defect origins and broad controls. Some ZnO nanoparticles exhibit very strong blue emissions, the intensity of which first increase and then decrease with annealing. These visible emissions exhibit strong and interesting excitation dependences: 1) the optimal excitation energy for blue emissions is near the bandgap energy, but the effective excitation can obviously be lower, even 420 nm (2.95 eV < Eg = 3.26 eV); in contrast, green emissions can be excited only by energies larger than the bandgap energy; and, 2) there are several fixed emitting wavelengths at 415, 440, 455 and 488 nm in the blue wave band, which exhibit considerable stability in different excitation and annealing conditions. Mechanisms for blue emissions from ZnO are proposed with interstitial‐zinc‐related defect levels as initial states. EPR spectra reveal the predominance of interstitial zinc in as‐prepared samples, and the evolutions of coexisting interstitial zinc and oxygen vacancies with annealing. Furthermore, good controllability of visible emissions is achieved, including the co‐emission of blue and green emissions and peak adjustment from blue to yellow. 相似文献
48.
A two-dimensional axisymmetric model is established to study the effect of electrode change on the solidification of slag and metal pool profile during electros... 相似文献
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