Mechanical Properties of Ni-Coated Single Graphene Sheet and Their Embedded Aluminum Matrix Composites

The effects of Ni coating on the mechanical behaviors of single graphene sheet and their embedded Al matrix composites under axial tensionare investigated using molecular dynamics (MD) simulation method. Theresults show that the Young's moduli and tensile strength of grapheneobviously decrease after Ni coating. The results also show that the mechanical properties of Al matrix can be obviously increased by embedding asingle graphene sheet. From the simulation, we also find that the Young'smodulus and tensile strength of the Ni-coated graphene/Al composite isobviously larger than those of the uncoated graphene/Al composite. Theincreased magnitude of the Young's modulus and tensile strength ofgraphene/Al composite are 52.27 and 32.32 at 0.01 K, respectively,due to Ni coating. By exploring the effects of temperature on the mechanicalproperties of single graphene sheet and their embedded Al matrix composites, it is found that the higher temperature leads to the lower critical strain and tensile strength.     

Teleportation Capability of Six-Qubit Cluster State

Recently Wei-Bo Gao et al. [Phys. Rev. Lett. 104 (2010) 020501]; reported on the creation of a 4-photon 6-qubit cluster state. It is shown this states can be utilized for perfect teleportation of arbitrary three qubit systems and controlled teleportation of an arbitrary two-qubit state. Therefore, the six-qubit cluster state as quantum channels is equivalent to that of maximally six-qubit entangled state.     

α-腈基阿魏酸基体在MALDI-TOFMS测定中的应用研究

在基体辅助激光解吸电离飞行时间质谱（MALDI－TOFMS）测定中基体的作用举足轻重。有效或特效基体的发现和应用不仅可提高测试灵敏度和分辨率,加大分子量测定范围,还能扩增测试样品的种类,推动MALDI－TOFMS应用的发展。目前MALDI－TOFMS分析的常用基体^[1,2]测定多肽、蛋白质的α-腈基－4－羟基肉桂酸（4HCCA）和介子酸（SA）效果比较理想;而测定糖类物质的2,5－二羟基苯甲酸（DHB）则不能完全适用于在组成、结构、序列以及连接方式上存在多样性的碳水化合物的分子;测定DNA的3－羟基吡啶甲酸（3－HPA）使用时必须对样品、溶剂甚至基体本身进行严格纯化,较为烦琐,测定含百个碱基以上大分子量DNA的灵敏度和分辨率还不理想。本文考察研究α-腈基阿魏酸（CFA）旨在寻找MALDI－TOFMS测定的有效新基体,为MALDI－TOFMS测定提供更多的基体选择。     

The Study of Primary Cosmic Ray Mass Composition Around the

The lg N_e-N_μ relationship has been studied from 4.4×10⁴ events (total observation time is 2.9×10⁶s)collected from Mt. Liang Wang Array (24.5°N, 102.9°E, 2720m above sea level). In order to study the mass composition at the knee, Monte-Carlo simulations for the EAS development and detection under same event selection criteria as used in the experimental data have been performed. The result shows that the mass composition of primary cosmic rays has no obvious change and the dominant component is light nuclei around the knee.     

反应堆核泵浦~3He-Ar-Xe气体激光腔内能量沉积数值模拟研究

在 TRIM软件计算结果的基础上利用蒙卡方法编制了能量沉积效率与损失率的 EDL计算软件 ,模拟计算了泵浦腔尺寸、混合气体中 3 He分压等参数与能量沉积密度之间的关系 ,研究了反应堆核泵浦激光腔内的能量沉积问题 ,推导出了能量沉积密度的函数关系式。     

介孔混合氧化物催化剂La-Co-Zr-O的制备与表征

 采用柠檬酸络合-有机模板剂分解法制备了(La+Co)/(La+Co+Zr)原子比为0.5的La-Co-Zr-O催化剂,并与传统的共沉淀法制备的La-Co-Zr-O催化剂进行比较. N2物理吸附结果表明,采用模板剂法制备的催化剂样品具有较大的比表面积(96.6～117.6 m2/g)和十分均匀的孔径(3.5～4.3 nm); X射线衍射、X射线光电子能谱和X射线吸收精细结构表征结果一致表明,催化剂中活性组分主要为高分散的Co3O4微晶(粒径为23～33 nm), 模板剂法制备的催化剂中所有组分的分散性均优于共沉淀法制备的催化剂. 程序升温还原实验结果表明,采用聚乙二醇辛基苯基醚与十六烷基三甲基溴化铵为混合模板剂制备的催化剂中Co3O4更容易被还原. Co-O 键的活动度与催化剂催化氧化反应的活性密切相关.     

Nonlinear vibration effects on the fatigue life of fluid-conveying pipes composed of axially functionally graded materials

Nonlinear Dynamics - Fatigue is inevitable in pipes conveying fluid due to unwanted vibration. Internal resonance occurs in such pipes due to pre-pressure. For the first time, the effects of...     

有机化学创新设计性实验*——氨基酸催化的不对称Aldol反应

氨基酸催化的不对称Aldol反应是不对称催化领域的一个研究热点,将其转化为设计性创新实验并面向化学院三年级学生开设。通过对反应底物、催化剂、溶剂等不同反应条件的探索,加深学生对手性、烯胺催化等概念、机理的理解,培养学生的科研能力及创新能力。     

用分光光度法研究表面带不同离子基团的温敏性微凝胶的胶体稳定性

对于胶体分散液的吸光度和波长的关系,Heller等人[1]已经总结出了其关系式:(A/c)c0=kλ-n,式中A为胶体粒子浓度为c时的吸光度,k为常数,λ为入射光波长.在胶体粒子浓度很小的情况下,n值可由此式求得:n=-(dlogA/dlogλ)c .     

用宇宙线大气簇射N_e-M_μ关系研究“膝”区原初成分

用梁王山宇宙线观测站获得的宇宙线大气簇射μ子数据,与假设原初分别为质子、氦核、中等核(Z=15)和铁核的Monte-Carlo模拟结果进行比较,结果显示宇宙线膝区原初成分无明显变化且以轻核为主．