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991.
J. Dou J. Li P.R. Herman J.S. Aitchison T. Fricke-Begemann J. Ihlemann G. Marowsky 《Applied Physics A: Materials Science & Processing》2008,91(4):591-594
Focussing of the output beam of optical fibers is required in a variety of applications. We present a laser micro-machining
technique for the fabrication of micro-lenses directly on the end face of single-mode silica fibers using a F2-laser processing station. A uniform ablation spot is projected onto the fiber end face and steered along a trajectory of
overlapping concentric circles. The lens profile is controlled by the spot size, the number of circles in the trajectory,
and the scanning speed. Strong 157 nm absorption by the silica glass facilitates precise structuring without micro-crack formation
in both cases. The surface quality of the fiber-lenses is characterized by AFM and SEM and reveals ∼ 100 nm rms roughness
with good control of the surface profile. Optical beam profiling indicates the possibility for creating spot sizes of 1/5
the core diameter at the fiber output.
PACS 42.81.Wg 相似文献
992.
993.
The up-conversion luminescence of Yb3+-doped yttrium lanthanum oxide transparent ceramic was investigated. It was ascribed to cooperative luminescence originated from the coupled states of the Yb3+ ion pairs. The proper doping of La2O3 can remove the cooperative luminescence of Yb3+ ion. But excessive La2O3 (at least 10 at.%) the cooperative up-conversion of Yb3+:Y2O3 is obtained again, and the intensity of up-conversion luminescence strengthens with the increase of La2O3 content. 相似文献
994.
基于单层板理论,结合有限元分析技术即应力分析、Hashin三维失效判定准则、包含4种基本损伤类型相互关联作用的材料性能退化方法及结构最终破坏判据等,建立了含辅助铺层层合板接头静载损伤失效分析方法. 同时,对层合板接头损伤扩展进行了模拟分析,损伤计算结果与试验分级加载试样X光进行了对比. 通过多种类型层合板接头静强度预测结果与试验结果对比及静载累积损伤规律分析表明,建立的静载三维累积损伤分析的强度预测方法可方便模拟不同结构尺寸层合板接头内部各铺层损伤起始、发展及结构最终破坏整个累积过程,同时获得其最终破坏强度及破坏模式. 该方法的预测结果与试验结果吻合较好. 相似文献
995.
本文构造了Navier-Stokes方程的最优控制区域分解方法的极小化序列,将非线性问题转化为在各子区域上并行求妥一系列线问题。 相似文献
996.
997.
窦士学 《高等学校化学学报》1982,3(4):502-508
应用Folry的缩聚理论处理铝酸盐型熔体(MO-Al2O3),得到了聚合阴离子的分布函数。通过缩聚反应平衡常数可将混合自由能和组元活度表达为熔体组成的函数。预期了产生凝胶化的条件。由模型所得理论曲线与实验结果进行了比较。 相似文献
998.
Meifang Zhu Weidong Yan Yan Lu Yanmo Chen Hans‐Jürgen P. Adler Petra Ptschke Jürgen Pionteck 《Macromolecular Symposia》2001,164(1):369-376
In this paper a polypropylene (PP) resin with controlled rheology was selected as polymer matrix and modified by melt mixing with polystyrene (PS) which has certain processing compatibility with PP. The effect of the addition of polyperoxide (PPX), peroxide modified PS particles (PS‐PPX), and maleic anhydride (MAH) to the PP/PS blend during melt mixing on the rheological behavior and morphology of the PP/PS blends has been carefully studied. 相似文献
999.
Hyun-Jung An Cheol-Jung Lee Ga-Eun Lee Youngwon Choi Dohyun Jeung Weidong Chen Hye Suk Lee Han Chang Kang Joo Young Lee Dae Joon Kim Jin-Sung Choi Eun Suh Cho Jong-Soon Choi Yong-Yeon Cho 《Experimental & molecular medicine》2022,54(1):35
Extracellular signal-regulated kinase 3 (ERK3) is an atypical member of the mitogen-activated protein kinase (MAPK) family, members of which play essential roles in diverse cellular processes during carcinogenesis, including cell proliferation, differentiation, migration, and invasion. Unlike other MAPKs, ERK3 is an unstable protein with a short half-life. Although deubiquitination of ERK3 has been suggested to regulate the activity, its ubiquitination has not been described in the literature. Here, we report that FBXW7 (F-box and WD repeat domain-containing 7) acts as a ubiquitination E3 ligase for ERK3. Mammalian two-hybrid assay and immunoprecipitation results demonstrated that ERK3 is a novel binding partner of FBXW7. Furthermore, complex formation between ERK3 and the S-phase kinase-associated protein 1 (SKP1)-cullin 1-F-box protein (SCF) E3 ligase resulted in the destabilization of ERK3 via a ubiquitination-mediated proteasomal degradation pathway, and FBXW7 depletion restored ERK3 protein levels by inhibiting this ubiquitination. The interaction between ERK3 and FBXW7 was driven by binding between the C34D of ERK3, especially at Thr417 and Thr421, and the WD40 domain of FBXW7. A double mutant of ERK3 (Thr417 and Thr421 to alanine) abrogated FBXW7-mediated ubiquitination. Importantly, ERK3 knockdown inhibited the proliferation of lung cancer cells by regulating the G1/S-phase transition of the cell cycle. These results show that FBXW7-mediated ERK3 destabilization suppresses lung cancer cell proliferation in vitro.Subject terms: Protein quality control, Ubiquitylation 相似文献
1000.
Shouzhi Wang Hengshuai Li Weidong He Hehe Jiang Yongliang Shao Yongzhong Wu Xiaopeng Hao 《Journal of Energy Chemistry》2021,(5):56-63
As promising electrode materials,transition metal oxides have attracted considerable attention owing to their excellent performance in electrochemical energy storage.However,their poor conductivity and fragile structure limit their practical application.In this study,a binder-free nickel oxide/oxynitride network(NiON WS)bifunctional electrodes with cation multivalent states that exhibit high energy storage performance were synthesized for the first time.The massive active sites,high specific surface areas,and multiple cation valence states of NiON WS were advantageous for electrochemical redox reaction during its application in supercapacitors(1283.5 mF cm-2)and lithium-ion batteries(1345.0 mA h g-1).Particularly,the NiON WS based flexible asymmetric SCs exhibit excellent capacitance and energy densities.First-principle calculations were employed to study the mechanism of the electrochemical performance improvement of NiON WS.This study demonstrates the potential of transition metal oxides electrode with high capacity and activity for electrochemical energy storage and conversion. 相似文献