Comparison of the boundary theory with the contact rule of phase regions and Gupta’s method

The phase boundary theory and the contact rule of phase regions are compared, and some weaknesses of the latter are manifested. The comparison between the Gupta’s method and the boundary theory method for constructing multicomponent isobaric sections is also presented.     

Cd-Sn(0.2)-Zn三元合金高压相图的测定

 为了验证三元合金高压相图的计算结果，本文采用高压DTA方法，测定了Cd-Sn-Zn三元系中x_Sn=20 at.%截面的高压垂直截面相图，实验压力为0、0.5、1.0、1.5 GPa。测得的常压相图（p=0 GPa）中其液相线与H. J. Bray的实验结果完全相符，所得高压相图与常压相图比较，在p=1.5 GPa时低共晶点上移了大约35 K，共析组成向富锌端移动了大约8%。     

Improvement of moving particle semi‐implicit method for simulation of progressive water waves

Precise simulation of the propagation of surface water waves, especially when involving breaking wave, takes a significant place in computational fluid dynamics. Because of the strong nonlinear properties, the treatment of large surface deformation of free surface flow has always been a challenging work in the development of numerical models. In this paper, the moving particle semi‐implicit (MPS) method, an entirely Lagrangian method, is modified to simulate wave motion in a 2‐D numerical wave flume preferably. In terms of consecutive pressure distribution, a new and simple free surface detection criterion is proposed to enhance the free surface recognition in the MPS method. In addition, a revised gradient model is deduced to diminish the effect of nonuniform particle distribution and then to reduce the numerical wave attenuation occurring in the original MPS model. The applicability and stability of the improved MPS method are firstly demonstrated by the calculation of hydrostatic problem. It is revealed that these modifications are effective to suppress the pressure oscillation, weaken the local particle clustering, and boost the stability of numerical algorithm. It is then applied to investigate the propagation of progressive waves on a flat bed and the wave breaking on a mild slope. Comparisons with the analytical solutions and experimental results indicate that the improved MPS model can give better results about the profiles and heights of surface waves in contrast with the previous MPS models. Copyright © 2017 John Wiley & Sons, Ltd.     

硝酸镧对长柄扁桃试管苗生根的影响

通过极差分析研究了不同浓度的硝酸镧和生长素组合对长柄扁桃试管苗生根的影响。结果表明:对长柄扁桃生根影响的主次因素为硝酸镧(La(NO3)3)>吲哚丁酸(IBA)>吲哚乙酸(IAA),最优组合为La(NO3)320 mg·L-1+IBA 0.2 mg·L-1+IAA 0.2 mg·L-1。在此条件下培养42 d后,长柄扁桃试管苗根的诱导频率达到89%,平均根长达到9.2 cm,每株根的平均个数为9.7个。对长柄扁桃的根组织活力进行测定,结果表明添加镧的处理组根系还原力是对照(不加镧)组的1.57倍。经过移栽驯化2个月后,长柄扁桃组培苗的移栽成活率达到94%,株高是对照的1.53倍。     

Main Q-eigenvalues and generalized Q-cospectrality of graphs

Let Q ^G denote the signless Laplacian matrix of a graph G. An eigenvalue μ of Q ^G is said to be a main Q-eigenvalue of G if μ has an eigenvector which is not orthogonal to an all-ones vector e. We give some basic properties of main Q-eigenvalues. For a graph G of order n, G is called Q-controllable if G has n distinct main Q-eigenvalues. We show that a graph H is generalized Q-cospectral with a Q-controllable G if and only if H is Q-controllable and there exists a unique rational orthogonal matrix R such that R _e = e, Q _H = R ^? Q _G R.     

酒石酸亚铁分光光度法测定茶多酚

采用没食子酸丙酯为基准物质酒石酸亚铁作为显色剂，光度法测定茶多酚制品中茶多酚的含量。最大吸收波长５４０ｎｍ摩尔吸光系数２．６５×１０＾３回收率为９８％－１０１％，相对标准偏差为０．９０％。方法简便，结果令人满意。     

大学化学课程的混合式教学实施与探索

为更好地建设精品资源共享课,提高人才培养质量,结合哈尔滨工业大学"大学化学国家精品课程"现有改革成果,初步尝试了面授加视频的混合式教学,探讨了在实践过程中取得效果和反映出的问题,并为混合式教学的推广实施提出了建议。旨在促进未来大学化学课程的在线教育发展,提高教学效果。     

Black-Sholes方程的解析解及收敛性分析

将经典的Black-Sholes方程转化为一类特殊的线性偏微分方程,并通过对其采用Fourier变换方法求得解析解,最后利用优核的相关性质对所得Black-Sholes方程解析解进行收敛性分析,证明了该解析解的收敛性.