Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of...Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of modulation is obvious in the two-point cross-section correlation map, and the correlation coefficients increase significantly with the Reynolds number. The influence of modulation is reflected in the tail of the probability density function of the near-wall flow signals, which expands as the Reynolds number increases. The flatness factor provides a quantitative description of the high fluctuation events due to modulation. Vortical structures associated with modulation are revealed by conditionally averaging the flow field of the near-wall extreme events, providing a depiction of how the influence of the large-scale structures penetrate towards the near-wall region.展开更多
目的研究枸杞子、淫羊藿的提取物与海参、牡蛎肉的冻干粉合用缓解体力疲劳的作用效果。方法按《保健食品检验与评价技术规范》缓解体力疲劳检测评价方法,将192只ICR(institute of cancer research)雄性小鼠随机分为阴性溶剂对照组、低(0...目的研究枸杞子、淫羊藿的提取物与海参、牡蛎肉的冻干粉合用缓解体力疲劳的作用效果。方法按《保健食品检验与评价技术规范》缓解体力疲劳检测评价方法,将192只ICR(institute of cancer research)雄性小鼠随机分为阴性溶剂对照组、低(0.14g/kg·bw)、中(0.27g/kg·bw)、高剂量(0.80g/kg·bw)组,每组48只,连续灌胃给药30d后,测定小鼠负重游泳时间、游泳后血清尿素、血乳酸含量和肝糖原含量。结果中、高剂量组小鼠负重游泳时间分别为(549±97)s、(541±91)s,较对照组(408±75)s明显增加(P<0.01);中、高剂量组小鼠血清尿素分别为(12.43±0.69)mmol/L、(12.53±0.85)mmol/L,较对照组(13.49±0.79)mmol/L明显降低(P<0.01);低、中、高剂量组肝糖原分别为(5.61±0.55)、(6.33±0.71)、(6.38±0.75)g/100g,均高于对照组(P<0.01)。中剂量组小鼠运动血乳酸含量显著低于对照组(P<0.01)。结论枸杞子、淫羊藿的提取物与海参、牡蛎肉的冻干粉合用具有缓解体力疲劳的作用。展开更多
Let C be a nonempty closed convex subset of a real Banach space E. Let S ： C→ C be a quasi-nonexpansive mapping, let T ： C→C be an asymptotically demicontractive and uniformly Lipschitzian mapping, and let F ：= ...Let C be a nonempty closed convex subset of a real Banach space E. Let S ： C→ C be a quasi-nonexpansive mapping, let T ： C→C be an asymptotically demicontractive and uniformly Lipschitzian mapping, and let F ：= {x ∈C ： Sx = x and Tx = x}≠Ф Let {xn}n≥0 be the sequence generated irom an arbitrary x0∈Cby xn＋i=（1-cn）Sxn＋cnT^nxn, n≥0.We prove the necessary and sufficient conditions for the strong convergence of the iterative sequence {xn} to an element of F. These extend and improve the recent results of Moore and Nnoli.展开更多
A graphene-coated microfiber(GCM)-based hybrid waveguide structure formed by wrapping monolayer graphene around a microfiber with length of several millimeters is pumped by a nanosecond laser at ~1550 nm, and multiord...A graphene-coated microfiber(GCM)-based hybrid waveguide structure formed by wrapping monolayer graphene around a microfiber with length of several millimeters is pumped by a nanosecond laser at ~1550 nm, and multiorder cascaded four-wave-mixing(FWM) is effectively generated. By optimizing both the detuning and the pump power, such a GCM device with high nonlinearity and compact size would have potential for a wide range of FWM applications, such as phase-sensitive amplification, multi-wavelength filter, all-optical regeneration and frequency conversion, and so on.展开更多
基金supported by the National Natural Science Foundation of China (Grants 11490551, 11472154, and 11322221)
文摘Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of modulation is obvious in the two-point cross-section correlation map, and the correlation coefficients increase significantly with the Reynolds number. The influence of modulation is reflected in the tail of the probability density function of the near-wall flow signals, which expands as the Reynolds number increases. The flatness factor provides a quantitative description of the high fluctuation events due to modulation. Vortical structures associated with modulation are revealed by conditionally averaging the flow field of the near-wall extreme events, providing a depiction of how the influence of the large-scale structures penetrate towards the near-wall region.
文摘目的研究枸杞子、淫羊藿的提取物与海参、牡蛎肉的冻干粉合用缓解体力疲劳的作用效果。方法按《保健食品检验与评价技术规范》缓解体力疲劳检测评价方法,将192只ICR(institute of cancer research)雄性小鼠随机分为阴性溶剂对照组、低(0.14g/kg·bw)、中(0.27g/kg·bw)、高剂量(0.80g/kg·bw)组,每组48只,连续灌胃给药30d后,测定小鼠负重游泳时间、游泳后血清尿素、血乳酸含量和肝糖原含量。结果中、高剂量组小鼠负重游泳时间分别为(549±97)s、(541±91)s,较对照组(408±75)s明显增加(P<0.01);中、高剂量组小鼠血清尿素分别为(12.43±0.69)mmol/L、(12.53±0.85)mmol/L,较对照组(13.49±0.79)mmol/L明显降低(P<0.01);低、中、高剂量组肝糖原分别为(5.61±0.55)、(6.33±0.71)、(6.38±0.75)g/100g,均高于对照组(P<0.01)。中剂量组小鼠运动血乳酸含量显著低于对照组(P<0.01)。结论枸杞子、淫羊藿的提取物与海参、牡蛎肉的冻干粉合用具有缓解体力疲劳的作用。
基金the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of MOE,Chinathe Dawn Program Foundation in Shanghai and partially supported by grant from the National Science Council of Taiwan
文摘Let C be a nonempty closed convex subset of a real Banach space E. Let S ： C→ C be a quasi-nonexpansive mapping, let T ： C→C be an asymptotically demicontractive and uniformly Lipschitzian mapping, and let F ：= {x ∈C ： Sx = x and Tx = x}≠Ф Let {xn}n≥0 be the sequence generated irom an arbitrary x0∈Cby xn＋i=（1-cn）Sxn＋cnT^nxn, n≥0.We prove the necessary and sufficient conditions for the strong convergence of the iterative sequence {xn} to an element of F. These extend and improve the recent results of Moore and Nnoli.
基金supported by National Natural Science Foundation of China under Grants 61290312, 61107072, 61107073, and 61475032supported by Program for Changjiang Scholars and Innovative Research Team in Universities of China (PCSIRT)the “111 Project” of China Education Ministry
文摘A graphene-coated microfiber(GCM)-based hybrid waveguide structure formed by wrapping monolayer graphene around a microfiber with length of several millimeters is pumped by a nanosecond laser at ~1550 nm, and multiorder cascaded four-wave-mixing(FWM) is effectively generated. By optimizing both the detuning and the pump power, such a GCM device with high nonlinearity and compact size would have potential for a wide range of FWM applications, such as phase-sensitive amplification, multi-wavelength filter, all-optical regeneration and frequency conversion, and so on.
