Magnetic properties and giant magnetoresistance effect of nanometer Fe−In2O3 granular films

Nanometer ferromagnetic metal-semiconductor matrix Fe−In₂O₃ granular films are fabricated by the radio frequency sputtering. Magnetic properties and the giant magnetoresistance (GMR) effect of Fe_x(In₂O₃)_1−x granular film samples are studied. The result shows that the magnetoresistance (MR) ratio Δρ/ρ ₀ value of the granular film samples with Fe volume fraction x=35% is 4.5% at room temperature. The temperature dependence (T=1.5–300 K) of the MR ratio Δρ/ρ ₀ value of Fe_0.35(In₂O₃)_0.65 granular films shows that Δρ/ρ ₀ value below 10 K increases rapidly with the decrease of the temperature, and when T=2 K, Δρ/ρ ₀ value is 85%. Through the study of the dependence of low field susceptibility on temperature and the hysteresis loops at different temperatures, it has been found that, when the temperature decreases to a critical point T _p=10 K, the change of the structure in Fe_0.35)In₂O₃)_0.65 granular films results in the transformation of state from ferromagnetic to spin-glass-like. The remarkable increase of the MR ratio Δρ/ρ ₀ value of Fe_0.35(In₂O₃)_0.65 granular films below 10 K seems to arise from the peculiar conducting mechanism of the granular film samples in the spin-glass-like state.     

An entanglement criterion for states in infinite-dimensional multipartite quantum systems

In(Phys Lett A,2002,297:4-8) an entanglement criterion for finite-dimensional bipartite systems is proposed:If ρ AB is a separable state,then Tr(ρA2) Tr(ρ2) and Tr(ρB2) Tr(ρ2).In the present paper this criterion is extended to infinite-dimensional bipartite and multipartite systems.The reduction criterion presented in(Phys Rev A,1999,59:4206-4216) is also generalized to infinitedimensional case.Then it is shown that the former criterion is weaker than the later one.     

Influence of Characteristics on Bending Strength of Layered Steel Fiber Reinforced Concrete

The influence of two main characteristics of steel fiber, the aspect ratio （Df） and volume fraction （ρf）, on the bending strength of Layered Steel Fiber Reinforced Concrete （LSFRC） is investigated by using orthogonal test. Via the variance analysis on the experimental results and trend analysis on the two characteristics, Df is found significantly related to the bending strength of LSFRC. The influence ratio is 63.3%. The bending strength of LSFRC increases if Df increases, makes better when Df reaches 100. ρf has ordinary influence on the bending strength of LSFRC. The influence ratio is 29.2%. Other characteristics, such as the shape of steel fiber and the mix proportion, have less influence. The best ρf contributing to the bending strength of LSFRC is 1.5 %. If ρf is greater than 1.5%, it has negative influence on the bending strength of LSFRC. So, ρf makes a limited contribution to the bending strength of LSFRC.     

Temperature dependence of densities of Sb and Bi melts

The densities of Sb and Bi melts were investigated by an improved Archimedean method. The results show that the density of the Sb melt decreases linearly with increasing temperature,but the density of the Bi melt firstly increases and then decreases as the temperature increases. There is a maximum density value of 10.002 g/cm3 at 310 ℃ ,about 39℃ above the melting point. The temperature depend-ence of the Sb melt is well fitted with the expression ρ =6.8590-5.8105×10-4T,and that of the Bi melt is fitted with ρ =10.3312-1.18×10-3T. The results were discussed from a microstructure viewpoint.     

The specific contribution of object’s origin on artifacts categorization

Gelman and Bloom found that adults and children＇s object naming was sensitive to how an object was created （man-made or not）, but they did not reveal on which specific level of conceptual system this effect was. Using a free-naming task and a force-choice task, two experiments were conducted to test a hypothesis that this effect was specifically on domain level （＂artifact/non-artifact＂ distinction）, in Experiment 1, participants were asked to name shortly-depicted objects, rate their confidence, and report their reasons for each naming response. Resuits showed that most of the naming responses in ＂man-made＂ condition were in artifact domain, and most in ＂natural＂ condition were in non-artifact domain, although in both conditions names were very divergent on basic level. In Experiment 2, another group of participants were asked to choose one from two names （one in artifact domain and the other in non-artifact domain） to match the same shortly-depicted objects presented in the first experiment. Results of Experiment 1 on domain level were replicated in Experiment 2. These convergent findings supported the hypothesis that the effect of object＇s origin is specifically on domain level of conceptual system of objects. Reasons explicitly reported for naming responses in Experiment 1 suggested that participants might automatically infer objects＇ functions in ＂man-made＂ condition but not in ＂natural＂ condition. Here the function-based hypothesis of artifacts classification is discussed.     

High-pressure sound velocity of perovskite-enstatite and the possible composition of the Earth’s lower mantle

The compressional sound velocity V_p for enstatite of polycrystalline specimens were measured at pressures from 40 to 140 GPa using the optical analytical techniques under shock loading. The dependence of V_P, (in km/s) on Hugoniot pressure (P, in GPa) can be described by InV_p= 3.079-0.691 In(P) + 0.094(lnP)². V_p satisfies Birch’s law:V _p = 4.068 + 1.677_ρ, where ρ is corresponding density, which indicated that enstatite is stable throughout the conditions of the lower mantle. The wave velocityP is 0.5% lower and the wave velocity S is 2% higher than that of PREM respectively. We concluded that the lower mantle is mainly composed of perovskite-(Mg_1-x, Fe_x) SiO₃ and only a small amount of (Mg_1-x, Fe_x) O is allowed in it.     

基于饱和执行器的不确定线性系统的非脆弱控制

对基于饱和执行器的不确定线性系统的非脆弱控制进行了研究.根据Lyapunov二次稳定性原理,证明并给出了椭球为闭环系统吸引域的充分条件,然后将该条件转化为线性矩阵不等式的优化问题,并估计出了闭环系统的最大吸引域,最后得到基于最大吸引域的非脆弱控制器参数的设计方法.仿真结果表明,与不考虑非脆弱控制相比,非脆弱控制器能使系统状态更快地稳定在原点.     

JAK3 mediatesc-myc gene expression induced by interleukin-2

C myc gene expression can be rapidly induced by IL 2 through intracellular signal transduction which is triggered by the interaction between IL 2 and its receptor (IL 2R). JAK3 which associates to the intracellular domain of IL_2R γ may play a critical role in this process. To reveal the action of JAK3 in c myc induction, a chimeric receptor gene IL_2R α/γ/Δ NJAK3 is constructed which consists of extracellular domain derived from IL 2R α subunit (IL_2R α), the transmembrane sequence derived from IL_2R γ and the cytoplasmic domain derived from the catalytic domain of JAK3 (Δ NJAK3), and then transfected this chimeric gene into mouse fibroblast cell line L929 β which had been transfected with IL_2R β gene and stably expressed IL_2R β in high level. In the transfectants coexpressing IL_2R β and α/γ/Δ NJAK3, the stimulation of IL_2 could intensively induce c myc gene expression. Because the whole cytoplasmic domain of IL_2R γ which could recruit signaling molecules was replaced by JAK3 and the c myc could be still induced by IL_2 in this situation, the results here gave the direct evidence demonstrating that JAK3 plays an important role in c myc gene expression induced by IL_2.     

约束系统的降阶输出反馈控制方法

探讨约束系统的降阶输出反馈控制器设计和吸引域估计问题。借助饱和函数的LDI（linear differential inclusion）描述形式，运用辅助反馈矩阵，得到了椭球集在吸引域内不变的充分条件，提出了一种具有最大吸引域的降阶输出反馈控制器的设计方法。     

Composition operators with linear fractional symbols on vector-valued Bergman spaces

0　IntroductionLetDdenotetheopenunitdiskinthecomplexplaneC , DitsboundaryanddAtheLebesguemeasureonD ,normal izedsothatA(D) =1.ForaBanachspace (X ,‖·‖X) ,wewriteH(D ,X)fortheclassofallX valuedanalyticfunctionsonD .Let1≤ p<∞ ,theX valuedBergmanspaceBp(X)istheclassofallf∈H(D ,X) forwhich‖f‖Bp(X) =∫D‖f(z)‖pXdA(z) 1 /p <∞ (1)IfX =C,thenwewriteBp =Bp(C) fortheclassicalBergmanspaces.Letφ∶D→Dbeananalyticself mapofD .Thenthee quation Cφf=f φdefinesacompositionoperator…     

基于平方和规划法的一种估计系统吸引域的改进算法

对于一个不是全局渐近稳定的非线性系统,研究其吸引域有重要的意义,多项式系统是非线性系统中一类非常重要的系统。平方和规划方法（Sum of Squares Programming,SOSP）是近年来提出的一种分析多项式非线性系统的方法,但将其用于估计系统吸引域时会遇到未知量双线性问题,无法直接进行求解。本文针对这一问题提出了一种可靠的算法,从而可以使用平方和规划方法估计多项式系统的吸引域,同时具有较快的求解速度。仿真算例验证算法的可行性和高效性。     

计算机构造李亚普诺夫函数及其应用

本文叙述Brayton与Tong在动态系统的稳定分析中建立的计算机构造李亚普诺夫函数的算法,及Michel等人推广的这种算法,该方法所建立的程序有可能确定系统在平衡状态x=0的吸引域和研究互联系统的稳定性。     

基于饱和关联Lyapunov函数的饱和离散系统吸引域估计

考虑执行器饱和的线性离散时间系统的吸引域估计问题,基于饱和关联的Lyapunov函数的吸引域估计,较之二次Lyapunov函数具有明显的优势,但这些结果仍具有一定的保守性。针对这一问题,提出了改进的局部稳定性条件,同时给出求解最大吸引域估计的优化问题。改进的稳定性条件含有更多的未知变量,已有结果是其一种特例。仿真算例验证了文中所得结论的正确性和优越性。     

Indian monsoon influences altitude effect of δ~(18)O in precipitation/river water on the Tibetan Plateau

The δ^18O variation in precipitation acquired from 28 stations within the network of Tibetan Observation and Research Platform （TORP） is studied, with the focus on the altitude effect of δ^18O in river water during monsoon precipitation in an effort to understand the monsoon influence on isotopic composition in annual river water. It is found that δ^18O in precipitation on the Plateau is influenced by different moisture sources, with significant Indian monsoon influence on δ^18O composition in plateau precipitation and river water. The δ^18O of water bodies in the monsoon domain is generally more depleted than that in the westerly domain, suggesting gradual rainout of southwesterly borne marine moisture in the course of long-distance transportation and lifting over the Himalayas. The lapse rate of δ^18O in river water with altitude is the largest during monsoon precipitation, due to the increased temperature vertical gradient over the southern Plateau region controlled by monsoon circulation. The combination of δ^18O in river water in monsoon （wet） and non-monsoon （dry） seasons shows a larger lapse rate than that in non-monsoon （dry） season alone. As the altitude effect of δ^18O in precipitation and river water on the Tibetan Plateau results from the combined effect of monsoon moisture supply and westerly moisture supply, the δ^18O composition and its altitude effect on the Plateau during monsoon seasons should be considered in the reconstruction of paleoelevation of the Tibetan Plateau.     

Forced extension of P-selectin construct using steered molecular dynamics

P-selectin, a 70-nm-long cellular adhesive molecule, possesses elastic and extensible properties when neutrophils roll over the activated endotheliam of blood vessel in inflammatory reaction. Transient formation and dissociation of P-selectin/ligand bond on applied force of blood flow induces the extension of P-selectin and relevant ligands.Steered molecular dynamics simulations were performed to stretch a single P-selectin construct consisting of a lectin(Lec) domain and an epithelial growth factor (EGF)-Iike domain, where P-selectin construct was forced to extend in water with pulling velocities of 0.005-0.05 nm/ps and with constant forces of 1000--2500 pN respectively. Resulting force-extension profiles exhibited a dual-peak pattern on various velocities, while both plateaus and shoulders appeared in the extension-time profiles on various forces. The force or extension profiles along stretching pathways were correlated to the conformational changes, suggesting that the structural collapses of P-selectin Lec/EGF domains were mainly attributed to the burst of hydrogen bonds within the major β sheet of EGF domain and the disruptions of two hydrophobic cores of Lec domain. This work furthers the understanding of forced dissociation of P-selectin/ligand bond.     

A geometric robust watermarking algorithm based on DWT-DCT and Zernike moments

This paper proposed a novel multibits watermarking algorithm providing robustness against geometric attacks. The robustness is achieved from three aspects： （1） Choosing the inscribed disk of the host image as the Zernike moments computation domain and the square in the disk as the watermarking embedding domain. （2） Embedding the watermark in the cascade discrete wavelet transform-discrete cosine transform （DWT-DCT） domain by modulating the specified coefficient pair in each sub block. （3） Saving two selected Zernike moments of the original watermarked image to estimate and correct the geometric attacks before watermark extraction. Experimental results show that the proposed algorithm is robust to any angle of rotation attacks and wide range of scaling attacks, and as well, a variety of other attacks such as lossy compression, common signal processing.     

Aerosol influence domain of Beijing and peripheral city agglomeration and its climatic effect

In recent years, along with development of industries and intensification of human activities, aerosol influ- ence and its climatic effect, and the aerosol-associated “aberrance” cloud phenomenon have increasingly drawn people’s attention. The term “A…     

Genesis of continental seismogenic zone and a new fault zone model

Experiments were conducted repeatedly on Mannari granite under different temperature and confining pressure conditions. Systematic micro- and submicro-structural and mechanical analyses of granite samples deformed under 1.5 GPa (confining pressure), at 25℃—650℃temperatures and at 2× 10^-6 s^-1 strain rate show the brittle-ductile deformation microstructures and microstructural associations similar to those observed in naturally deformed crustal rocks and minerals. Brittle fracturing and crystalline plasticity co-exist and react with each other in the brittle-ductile transition domain of the continental lithosphere. The interaction between the different mechanisms in the transitional domain results in the variation of anomalous strength values, which may best explain the genesis of the continental seismogenic zone. A new fault zone model is proposed on the basis of detailed micromechanical and microstructural analyses.     

参激Duffing-Van Der Pol振子的混沌演化与激变

运用分岔图、相图、Poincare截面图、快速傅里叶变换(FFT)图、最大Lyapunov指数图、吸引域等各种数值方法,研究了Duffing-Van Der Pol振子在参数激励下的一系列动力学行为,揭示了该系统复杂的分岔、混沌现象.通过共存时吸引子及相应吸引域的变化,研究了混沌吸引子的形成与激变.