半共格界面铜镍双层膜力学差异机制纳观探析

为深入了解纳米金属多层膜在沉积法交替制备中, 因晶格失配制备出不同半共格界面的金属多层膜受载诱导的力学特性差异的机制，本文作者基于经典力学的分子动力学法，对半共格Cu基Ni膜和Ni基Cu膜两种界面结构的力学性能展开探析，揭示出多层膜半共格界面失配位错网与压痕诱导产生可动位错的相互作用规律. 研究发现: 铜镍双层膜半共格界面结构可有效提升力学性能，归因于铜镍半共格界面受载产生的柏氏矢量Shockley分位错的差异. Cu基Ni膜半共格界面上的失配位错网对压痕中产生的可动位错表现为排斥，有利于位错穿透半共格区域进入铜基中，对外表现为强化作用；Ni基Cu膜半共格界面上的失配位错网对压痕中产生的可动位错表现为吸引，阻碍位错穿透半共格区域进入镍基中，对外表现为软化作用，增强了材料抵抗变形的能力、耐磨性和韧性. 该性质差异可用Koehler提出的两种不同材料模量间镜像力理论解释. 此研究结果对铜镍多层膜作为涂层应用于微机电系统、海洋装备和航空航天等重大战略领域有着重要理论指导意义与借鉴价值.      

Two novel abietane norditerpenoids with anti-inflammatory properties from the roots of Salvia miltiorrhiza var. alba

Salvialba acid (1) with a novel abietane norditerpenoid skeleton and 2-hydroxydihydrotanshinone I (2), a new abietane norditerpenoid, were isolated from Salvia miltiorrhiza var. alba. Their structures were elucidated by spectroscopic analysis and X-ray diffraction. The absolute configuration of 1 was determined by an electronic circular dichroism (ECD) experiment and TDDFT ECD computations. A possible biosynthesis pathway is proposed for 1. Compounds 1 and 2 were demonstrated to have anti-inflammatory effects on vascular inflammation induced by TNF-α in human aortic endothelial cells (HAECs).     

Allele frequency of 19 autosomal STR loci in the Bai population from the southwestern region of mainland China

The aim of this study was to investigate a 19 STR loci database using the Bai population from China. This multiplex amplification kit included 13 CODIS STR markers and six plus STR markers (D19S433, Penta E, D2S1338, Penta D, D6S1043, and D12S391) that were successfully analyzed by using 1158 DNA samples from the Bai population from the southwestern part of mainland China. These results indicate that this multiplex amplification kit may provide significant polymorphic information for kinship testing and relationship investigations.     

Capillary electrophoresis fingerprinting coupled with chemometrics to evaluate the quality consistency and predict the antioxidant activity of Sanhuang tablet as part of its quality control

A capillary electrophoresis fingerprint was constructed for Sanhuang tablet, a Chinese traditional patent medicine, that was commonly used in clinical practice, where the isosceles trapezoid method was first applied for the optimization of background electrolyte solution, and the resolution index was performed to assess the experimental conditions; furthermore, a novel linear quantitative fingerprint method was established for accurate qualitative and quantitative discrimination of the test samples from diverse commercial brands. The fingerprint analysis coupled with quantitative determination of two components was employed to elucidate that the quality consistency of the products was relatively good within one manufactory, but poor among different companies for the 30 batches of samples. In addition, the fingerprint–efficacy relationship between chemical components and antioxidant activity in vitro was investigated using partial least squares analysis, and the calibration and prediction of the antioxidant activity of the selected samples via fingerprint data were presented with the desired results. This work illustrates that the proposed fingerprint analysis based on linear quantitative fingerprint method can be applied for the quality evaluation of traditional Chinese medicine and herbal preparations as part of their quality control, and the constructed mathematical model is particularly suitable for depicting the fingerprint–efficacy relationship.     

Two new labdane diterpenoids from the rhizomes of Isodon yuennanensis

Two new labdane diterpenoids, s-trans-8(17),12E,14-labdatrien-20-oic acid (1), s-trans-12E,14-labdadien-20,8β-olide (2), along with 10 known compounds, hinokiol (3), ursonic acid (4), 2α,3α-dihydroxyolean-12-en-28-oic acid (5), 2α,3β,23-trihydroxyolean-12-en-28-oic acid (6), ethyl 3-(3,4-dihydroxyphenyl)lactate (7), ethyl rosmarinate (8), (Z,E)-2-(3,4-dihydroxyphenyl)ethenyl caffeic ester (9), tridecanoic acid (10), β-sitosterol (11) and daucosterol (12), were isolated from the 70% acetone extract of the rhizomes of Isodon yuennanensis. Their structures were elucidated based on the analyses of extensive spectroscopic data and physicochemical properties.     

富氮杂环配位超分子化合物的合成、结构及光谱特征

以2,6-二(5-甲基-1H-吡唑-3-基)吡啶(简写为H2L)为第一配体,以均苯四甲酸和乙酸为第二配体,合成了2个新的配位超分子化合物[Ni(H2L)2]·(Me O-H2BTA)2(1)和Mn(H2L)(Ac)2(2)(H4BTA∶均苯四甲酸,HAc∶乙酸),并由元素分析、红外光谱、紫外-可见光谱以及X射线单晶衍射等对其进行了表征,分析了其光谱及结构特征。晶体结构分析表明,化合物1属于正交晶系,Pbcn空间群,a=0.95747(8)nm,b=1.99273(13)nm,c=2.50175(13)nm,α=90°,β=90°,γ=90°,V=4.773 3(6)nm3,Z=4;化合物2属于单斜晶系,Cc空间群,a=1.11300(13)nm,b=2.0239(2)nm,c=0.97308(12)nm,α=90°,β=118.555(16)°,γ=90°,V=1.9253(4)nm3,Z=4。     

大学复变函数课程与高中数学的衔接

分析近二十年来高中数学经历的三次重要改革中复数部分教学内容、要求的变化和大学数学与应用数学专业复变函数教材处理复数部分的状况.在此基础上,给出大学复变函数课程关于复数部分的一些教学建议.     

Structural characteristics and spectral behaviours of the preferred conformation of a cyclic pentapeptide,cycloaspeptide G from Cordyceps-colonising fungus Isoria farinose

The density functional theory (DFT) is exploited to search the stable conformations of a cyclic pentapeptide called cycloaspeptide G from Cordyceps-colonising fungus Isoria farinose. Its time-dependent version is employed to describe the profiles of electronic circular dichroism (ECD) of the preferred conformation, where the solvent effect in methanol is taken into account on the basis of the polarisable continuum model computation. Four stable conformers are optimised, and the results of the harmonically vibrational frequency calculations illustrate that they are the true minima. In the vibrational CD spectrum at the B3LYP/6-31G* level, the negative peak at 3334 cm^?1 has its origin of the NH stretches of the peptide ring. In the ECD spectrum at the B3LYP/6-31G* level, three strong bands are negative, positive, and negative. Since the ECD spectrum at the B3LYP/6-31G* level is remarkably different from that at the B3LYP/6-31G level, it is necessary for the expended functions to be added to the 6-31G basis set.