基于可信向量的知识图谱上下文感知表示学习

面向知识图谱的表示学习在低维语义空间中对实体和关系进行编码,提升了知识理解和推理能力。传统的平移模型在处理知识图谱中的一对多、多对一以及多对多这些复杂关系时,难以区分在某一属性具有相同语义的实体。本文构建了一种基于二值可信向量的平移模型(TransV),通过向量不同维度的元素值控制对应属性的激活与抑制程度,使不同的关系关注不同的实体属性信息,提高模型处理复杂关系的效果。除了知识图谱中的三元组信息,非结构化文本中包含了丰富的语义信息,能够提高实体表达能力。利用与实体相关的文本信息,构建了一种融合上下文信息的基于二值可信向量的知识图谱表示学习模型(CKRV),使得三元组信息与语义信息能相互影响、相互融合。实验结果表明,该方法复杂度更低,在实体预测准确性方面有明显提升。     

Using Reduced Graphene Oxide to Generate Q-Switched Pulses in Er-Doped Fiber Laser

Using the reduced graphene oxide(rGO) as a saturable absorber(SA) in an Er-doped fiber(EDF) laser cavity,we obtain the Q-switching operation. The rGO SA is prepared by depositing the GO on fluorine mica(FM) using the thermal reduction method. The modulation depth of rGO/FM is measured to be 3.2%. By incorporating the rGO/FM film into the EDF laser cavity, we obtain stable Q-switched pulses. The shortest pulse duration is3.53 μs, and the maximum single pulse energy is 48.19 nJ. The long-term stability of working is well exhibited.The experimental results show that the rGO possesses potential photonics applications.     

Reduced graphene oxide as saturable absorbers for erbium-doped passively mode-locked fiber laser

We demonstrate a nanosecond mode-locked erbium-doped fiber laser(EDFL)based on a reduced graphene oxide(RGO)saturable absorber(SA).The RGO SA is prepared by depositing the graphene oxide(GO)on fluorine mica through thermal reduction of GO.A scanning electron microscope(SEM),Raman spectrometer,and x-ray photoelectron spectroscopy(XPS)are adopted to analyze the RGO characteristics.The results show that the reduction degree of graphene oxide is very high.By embedding the RGO SA into the EDFL cavity,a stable mode-locked fiber laser is achieved with a central wavelength of 1567.29 nm and repetition rate of 12.66 MHz.The maximum output power and the minimum pulse duration are measured to be 18.22 mW and 1.38 ns respectively.As far as we know,the maximum output power of18.22 mW is higher than those of other nanosecond mode-locked oscillators reported.Such a nanosecond pulse duration and megahertz repetition rate make this mode-locked erbium-doped fiber laser a suitable seed oscillator for high-power applications and chirped pulse amplifications.     

Temperature dependence of spin pumping in YIG/NiOx/W multilayer

We report the temperature dependence of the spin pumping effect for Y₃Fe₅O₁₂ (YIG, 0.9 μm)/NiO (t_NiO)/W (6 nm) (t_NiO = 0 nm, 1 nm, 2 nm, and 10 nm) heterostructures. All samples exhibit a strong temperature-dependent inverse spin Hall effect (ISHE) signal I_c and sensitivity to the NiO layer thickness. We observe a dramatic decrease of I_c with inserting thin NiO layer between YIG and W layers indicating that the inserting of NiO layer significantly suppresses the spin transport from YIG to W. In contrast to the noticeable enhancement in YIG/NiO (t_NiO ≈ 1-2 nm)/Pt, the suppression of spin transport may be closely related to the specific interface-dependent spin scattering, spin memory loss, and spin conductance at the NiO/W interface. Besides, the I_c of YIG/NiO/W exhibits a maximum near the T_N of the AF NiO layer because the spins are transported dominantly by incoherent thermal magnons.     

电化学间接测量法研究谷胱甘肽在多壁碳纳米管和活性炭上的吸附

选取谷胱甘肽(GSH)作为小分子代表物,利用Cr(VI)与GSH的相互作用,即K2Cr2O7/H2SO4溶液加入GSH前后Cr(VI)还原峰电流值的差异,通过差分脉冲伏安法(DPV)的测定,可以间接测出GSH的含量.尝试将这种电化学间接测量法应用于研究多壁碳纳米管(MWCNTs)与商业活性炭(AC)对GSH的吸附行为.利用该方法可以确立GSH在二者的吸附量(Q)与吸附平衡浓度(Ce)的关系,绘制吸附等温曲线.根据Langmuir方程和Freundlich方程的拟合分析,证明了与商业活性炭相比,GSH在MWCNTs上的吸附更倾向Freundlich模型,即多分子层吸附.利用扫描电子显微镜(SEM)和透射电子显微镜(TEM)进行形貌表征,发现MWCNTs具有发达的堆积孔结构,有利于GSH小分子内扩散和吸附,与实验结果一致.     

添加剂对含盐废水焚烧结焦特性的影响

本文在鼓泡流化床废水焚烧实验台上,以SEM/EDX分析和XRD检测为手段,系统研究不同添加剂对床层结焦特性的影响,探讨其抑制床层结焦的机理。实验结果表明:Al_2O_3对结焦的抑制作用最明显,高岭黏土,Fe_2O_3和CaCO_3其次。在本实验涉及的床温范围内,添加剂对结焦的抑制主要是物理作用的结果。     

树莓派在物理实验教学中的应用

树莓派是近年来新兴的微型计算机,它造价低廉但功能强大,目前正被广泛运用于青少年编程学习等方面.树莓派在物理实验教学领域同样具有应用价值.从“互联网+物理”和“实验数据绘图”两个方面对树莓派在物理实验教学的运用进行展开介绍和示例展示.互联网+物理不仅能实现班级实验数据的上传和分享,还能实现对课堂进行摄录,完成物理微课堂、云课堂的录制;实验数据绘图,充分利用了树莓派的运算、渲染能力以及丰富的音视频输出接口,能实现实时数据的图表绘制,摒弃传统实验教学中课上记录、课下绘图的方法.     

High-power passively Q-switched Nd:GdVO_4 laser with a reflective graphene oxide saturable absorber

A single output Q-switched Nd:GdVO4 laser with a reflective graphene oxide(GO) saturable absorber was demonstrated. The shortest pulse duration in the Q-switched laser is 115 ns, and the output power ranges from1.23 W at 1.71 MHz to 2.11 W at 2.50 MHz when the pump power rises from 7.40 to 10.90 W with the utilization of GO Langmuir–Blodgett(LB) films based on the convenient and low-cost LB technique. To the best of our knowledge, it is the highest output power in a Q-switched laser with a GO saturable absorber.     

Experimental observation of interlayer perpendicular standing spin wave mode with low damping in skyrmion-hosting [Pt/Co/Ta]10 multilayer

An interlayer perpendicular standing spin wave mode is observed in the skyrmion-hosting [Pt/Co/Ta]₁₀ multilayer by measuring the time-resolved magneto-optical Kerr effect. The observed interlayer mode depends on the interlayer spin-pumping and spin transfer torque among the neighboring Co layers. This mode shows monotonically increasing frequency-field dependence which is similar to the ferromagnetic resonance mode, but within higher frequency range. Besides, the damping of the interlayer mode is found to be a relatively low constant value of 0.027 which is independent of the external field. This work expounds the potential application of the [heavy-metal/ferromagnetic-metal]_n multilayers to skyrmion-based magnonic devices which can provide multiple magnon modes, relatively low damping, and skyrmion states, simultaneously.