论对分课堂推动高校思政课教学“四重转变”的问题与策略

对分课堂教学是一种课堂教学的创新模式,它与高校思政课教学具有很好的适配性。本文从师生关系、教学内容、教学互动、教学流程四个方面探究高校思政课运用对分课堂的优势及存在的问题,指出其推动高校思政课教学改革创新的“四重转变”,有利于高校思政课提质增效。

浅谈社会管理创新视角下公安群众工作的三重转变

伴随经济转轨与社会转型,,社会管理创新成为我国具有战略意义的制度安排。对于公安机关而言,社会管理创新的发展要求吁求着新的公安群众工作模式的产生。具体而言,其理念要从主体性转向主体间性,路径上要从单向指令模式转向双向交流模式,评价方式上要从一元主体评价转向多元主体评价。这三重转变内包含着社会管理创新的价值诉求,也揭示着未来公安工作的发展方向。

无定形梳状高分子固体电解质的二重玻璃化转变及典型VTF特征

研究了交替马来酸酐共聚物多缩乙二醇酯（ＣＰ３５０）－ＬｉＮＯ３络合物的热行为及离子导电性。实验表明：ＣＰ３５０／ＬｉＮＯ３络合物在所研究的［Ｌｉ］／［ＥＯ］配比范围呈均相无定形并具有二重玻璃化转变。２个玻璃化转变温度均随盐含量的增加而上升。离子电导率随盐浓度的变化出现１个极大值，室温电导率最大可达３．７２×１０－５Ｓ／ｃｍ。导电行为呈典型ＶＴＦ特征。

消费导向型经济中的制度创新

当前,我国消费正经历着消费水平、消费体制上的双重转变,消费在国民经济运行中已处于主导地位。经济形态由生产导向型向消费导向型转变,这客观上要求我们启动市场,刺激消费需求。扩张消费需求关键是对传统的消费制度安排进行创新,在消费领域非正式约束、正式约束、实施机制三方面的制度创新已日益重要。

Microstructural evolution and phase transformation during partial remelting of in-situ Mg_2Si_p/AM60B composite

The microstructural evolution and phase transformations during partial remelting of in-situ Mg2Sip/AM60B composite modified by SiC and Sr were investigated. The results indicate that SiC and Sr are effective for refining primary α-Mg grains and Mg2Si particles. After being partially remelted, a semisolid microstructure with small and spheroidal primary α-Mg particles can be obtained. The microstructural evolution during partial remelting can be divided into four stages： the initial rapid coarsening, structural separation, spheroidization and final coarsening, which are essentially caused by the phase transformations of β→α, α＋β→L and α→L, α→L, and α→L and L→α, respectively. The Mg2Si particles have not obvious effect on the general microstructural evolution steps, but can slower the evolution progress and change the coarsening mechanism. During partial remelting, Mg2Si particles first become blunt and then become spheroidal because of melting of their edges and corners, and finally are coarsened owing to Ostwald ripening.

Relation of normal load with test temperature at mild−severe wear transition state for Mg−Gd−Y−Zr alloy

The wear behavior and mild−severe(M−S)wear transition of Mg−10Gd−1.5Y−0.4Zr alloy were investigated within a temperature range of 20−200℃.The morphologies and compositions of worn surfaces were examined to identify the wear mechanisms using scanning electron microscope and energy dispersive X-ray spectrometer.The microstructure and hardness in the subsurfaces were analyzed to reveal the M−S wear transition mechanism.Under a constant loads of 20,35 and 40 N,each wear rate−test temperature curve presented a turning point which corresponded to the M−S wear transition.In mild wear,the surface material was plastically deformed and hence was strainhardened,whereas in severe wear,the surface material was dynamically recrystallized and consequently was softened.It has been found that the critical temperature for M−S wear transition decreases with increasing the normal load,and the normal load exhibits an almost linear relationship with critical temperature for M−S wear transition.This work reveals that the M−S wear transition of the studied alloy conforms to the surface DRX temperature criterion.

Dimension Reduction Method in Thermodynamics of Multireaction Systems(Ⅱ)Residual Properties,Property Changes of Mixing and Excess Properties Relations

Based on the fundamental thermodynamic principle the relationships of the residual properties, the property changes of mixing and the excess properties between the hypothetical solution of unreacted independent species and the equilibrated solution of actual species have been established. The hypothetical solution provides a way of reducing the dimensionality of problem and simplifying the analysis.

Undrained response of reconstituted clay to cyclic pure principal stress rotation

A series of monotonic and rotational shearing tests are carried out on reconstituted clay using a hollow cylinder apparatus under undrained condition. In the rotational shearing tests, the principal stress axes rotate cyclically with the magnitudes of the principal stresses keeping constant. The anisotropy of the reconstituted clay is analyzed from the monotonic shearing tests. Obvious pore pressure is induced by the principal stress rotation alone even with shear stress q0=5 k Pa. Strain components also accumulate with increasing the number of cycles and increases suddenly at the onset of failure. The deviatoric shear strain of 7.5% can be taken as the failure criterion for clay subjected to the pure cyclic principal stress rotation. The intermediate principal stress parameter b plays a significant role in the development of pore pressure and strain. Specimens are weakened by cyclic rotational shearing as the shear modulus decreases with increasing the number of cycles, and the shear modulus reduces more quickly with larger b. Clear deviation between the directions of the principal plastic strain increment and the principal stress is observed during pure principal stress rotation. Both the coaxial and non-coaxial plastic mechanisms should be taken into consideration to simulate the deformation behavior of clay under pure principal stress rotation. The mechanism of the soil response to the pure principal stress rotation is discussed based on the experimental observations.

PHASE TRANSITION IN SEQUENCE UNIQUE RECONSTRUCTION

In this paper, sequence unique reconstruction refers to the property that a sequence is uniquely reconstructable from all its K-tuples. We propose and study the phase transition behavior of the probability P（K） of unique reconstruction with regard to tuple size K in random sequences （iid model）. Based on Monte Carlo experiments, artificial proteins generated from lid model exhibit a phase transition when P（K） abruptly jumps from a low value phase （e.g. 〈 0.1） to a high value phase （e.g. 〉 0.9）. With a generalization to any alphabet, we prove that for a random sequence of length L, as L is large enough, P（K） undergoes a sharp phase transition when p ≤ 0.1015 where p = P （two random letters match）. Besides, formulas are derived to estimate the transition points, which may be of practical use in sequencing DNA by hybridization. Concluded from our study, most proteins do not deviate greatly from random sequences in the sense of sequence unique reconstruction, while there are some ＂stubborn＂ proteins which only become uniquely reconstructable at a very large K and probably have biological implications.

The Gravity Field Variation Caused by Inner Core Super Rotation

Due to the super rotation of the Earth＇s inner core, the tilted figure axis of the inner core would progress with respect to the mantle and thus cause the variation of the Earth＇s external gravity field. This paper improves the present model of the gravity field variation caused by the inner core super rotation. Under the assumption that the inner core is a stratifying ellipsoid whose density function is fitted out from PREM and the super rotation rate is 0.27-0.53°/yr, calculations show that the global temporal variations on the Earth＇s surface have a maximum value of about 0.79-1.54×10^3 pGal and a global average intensity of about 0.45-0.89×10^ 3 μGal in the whole year of 2007, which is beyond the accuracy of the present gravimetry and even the super conducting gravimeter data. However, both the gravity variations at Beijing and Wuhan vary like sine variables with maximal variations around 0.33 pGal and 0.29 pGal, respectively, in one cycle. Thus, continuous gravity measurements for one or two decades might be able to detect the differential motion of the inner core.