Preparation and tribological properties of DLC/Ti filmby pulsed laser arc deposition

This paper reports that DLC (diamond like carbon)/Ti and DLC films were prepared by using pulsed laser arc deposition. R-ray diffraction, Auger electron spectroscopy, Raman spectroscopy, atomic force microscopy, nanoindenter, spectroscopic ellipsometer, surface profiler and micro-tribometer were employed to study the structure and tribological properties of DLC/Ti and DLC films. The results show that DLC/Ti film, with $I(D)/I(G)$ 0.28 and corresponding to 76{\%} sp$^{3}$ content calculated by Raman spectroscopy, uniform chemical composition along depth direction, 98 at{\%} content of carbon, hardness 8.2 GPa and Young's modulus 110.5 GPa, compressive stress 6.579 GPa, thickness 46~nm, coefficient of friction 0.08, and critical load 95mN, exhibits excellent mechanical and tribological properties.     

霍尔元件线度对磁场测量影响的研究

在原有霍尔效应原理的基础上,利用微积分的基本方法和相关的物理知识推导非均匀磁场中利用霍尔效应测量磁场的理论公式,并结合该公式理论解释实验中对于霍尔元件线度的要求,以及说明非均匀磁场的测量对霍尔元件线度的要求,从而说明实验中经常遇到的一类问题——平均值问题。     

宽带脉冲DC SQUID核磁共振谱仪的研制

DC SQUID NMR在研究凝聚态体系 ,尤其在研究低温下量子有序态等方面是一项非常有价值的技术。文中描述了在带有宽带电子设备的商业 DC SQUID基础上建立起宽带脉冲谱仪 ,以及马鞍形激发线圈、采集线圈和低温装置的设计 ,并测量了铂样品在 4.2 Kz温度下的 NMR信号。     

Microwave reflection properties of planar anisotropy FesoNi50 powder/paraffin composites

The reflection properties of planar anisotropy Fe50Ni50 powder/paraffin composites have been studied in the microwave frequency range.The permeability of Fe50Ni50 powder/paraffin composites is greatly enhanced by introducing the planar anisotropy,and can be further enhanced by using a rotational orientation method.The complex permeability can be considered as the superposition of two types of magnetic resonance.The resonance peak at high frequency is attributed to the natural resonance,while the peak at low frequency is attributed to the domain-wall resonance.The simulated results of the microwave reflectivity show that the matching thickness,peak frequency,permeability,and permittivity are closely related to the quarter wavelength matching condition.The Fe50Ni50 powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band(1-2 GHz).     

Regulation of Zn/Sn ratio in kesterite absorbers to boost 10% efficiency of Cu_2ZnSn(S,Se)_4 solar cells

The Zn/Sn ratio in Cu_2ZnSn(S,Se)_4(CZTSSe)films has been regulated to control the composition-related phase,defect,and photoelectric properties for high performance kesterite solar cells.It is found that the increase in the Zn/Sn ratio can slightly narrow the energy band gap to extend the light absorption range and improve the photocurrent.Optimal Zn/Sn ratio of 1.39 in CZTSSe film is obtained with the least secondary phase,the lowest defect density,and the longest charge recombination lifetime.Up to 10.1%photoelectric conversion efficiency has been achieved by this composition regulation.     

Quantum oscillation measurements in high magnetic field and ultra-low temperature

The physical properties of a solid are determined by the electrons near the Fermi energy and their low-lying excitations. Thus, it is crucially important to obtain the band structure near the Fermi energy of a material to understand many novel phenomena that occur, such as high-T_c superconductivity, density waves, and Dirac-type excitations. One important way to determine the Fermi surface topology of a material is from its quantum oscillations in an external magnetic field. In this article, we provide a brief introduction to the substation at the Synergetic Extreme Condition User Facility(SECUF),with a focus on quantum oscillation measurements, including our motivation, the structure of and the challenges in building the substation, and perspectives.     

色氨酸与稀土元素Eu(Ⅲ)配合物的合成及配位位置的研究

氨基酸是生命系统中蛋白质的基本结构单位.本文通过共沉淀法合成了色氨酸与稀土元素Eu(Ⅲ)的固体配合物,并对其进行了光谱及波谱研究,确定了配合物的配位机理及配位点.     

迷迭香中微量元素与黄酮类化合物的含量分析

以甲醇为溶剂用索氏提取法提取迷迭香中总黄酮,用比色法测定了其含量;并采用电感耦合等离子体-原子发射光谱仪(ICP-AES)测定了该植物中9种微量元素的含量。结果表明:迷迭香中黄酮类化合物的含量为1.61mg/g,加样回收率为98.98%—100.06%,RSD为0.419%(n=6),该法操作简便,重现性好,适合于黄酮类化合物含量的测定;迷迭香中Fe、K、Mg、Mn、Zn含量丰富。     

以最大原子密度定义合金相中的第一近邻团簇

本文提出利用不同壳层所包含的径向原子密度, 即单位体积内的原子个数随着径向的分布, 来方便而精确地定义团簇, 即具有最大径向原子密度的且表面呈现三角密堆结构的完整壳层为第一近邻团簇. 最后以Al-Ni-Zr合金相为例说明了该方法的合理性与适用性, 及此方法所定义的团簇与非晶形成的关系.