结构与参量不确定的网络与网络之间的混沌同步

进行了结构与参量不确定的网络与网络之间的混沌同步研究．通过设计适当的控制输入,不但实现了两个复杂网络之间的混沌同步,而且网络节点状态方程中的未知参量和网络内部节点之间的耦合强度也被同时确定．通过采用具有调制损耗的CO2激光器的状态方程进行仿真实验,发现网络与网络之间的同步性能非常稳定．     

土壤源热泵系统冷凝热回收的优化研究

文中提出了一种土壤源热泵冷凝热回收系统,能够减少冬夏两季土壤源热泵系统从土壤冷热源排放吸收热量不均对土壤温度场所造成的影响,并结合火用平衡方程建立了土壤源热泵系统冷凝热回收的优化模型。基于此模型,探讨了系统冷凝器和地下埋管的优化配置,通过模拟计算对该系统在制冷工况下改进前后的运行情况进行了分析对比,结果显示土壤源冷凝热回收系统应用于实际工程能够提高整个系统的COP以及火用效率。     

An improved loopless mounting method for cryocrystallography

Based on a recent loopless mounting method, a simplified loopless and bufferless crystal mounting method is developed for macromolecular crystallography. This simplified crystal mounting system is composed of the following components: a home-made glass capillary, a brass seat for holding the glass capillary, a flow regulator, and a vacuum pump for evacuation. Compared with the currently prevalent loop mounting method, this simplified method has almost the same mounting procedure and thus is compatible with the current automated crystal mounting system. The advantages of this method include higher signal-to-noise ratio, more accurate measurement, more rapid flash cooling, less x-ray absorption and thus less radiation damage to the crystal. This method can be extended to the flash-freeing of a crystal without or with soaking it in a lower concentration of cryoprotectant, thus it may be the best option for data collection in the absence of suitable cryoprotectant. Therefore, it is suggested that this mounting method should be further improved and extensively applied to cryocrystallographic experiments.     

Operators’s-parameterized ordering and its classical correspondence in quantum optics theory

In reference to the Weyl ordering xmpn→(1/2)mΣι=0m(ιm)Xm-ιPnXι , where X and P are coordinate and momentum operator, respectively, this paper examines operators’s-parameterized ordering and its classical correspondence, finds the fundamental function-operator correspondence ((1-s)/2)(n+m)/2Hm,n((2/(1-s))～(1/2)α,(2/(1-s))～(1/2)α)→a+man,and its complementary relation αnα*m→(-i)n+m((1-s)/2)(m+n)/2:Hm,n(i(2/(1-s))～(1/2)a+,i((2/(1-s))～(1/2)a):,where H m,n is the two-variable Hermite polynomial, a, a+ are bosonic annihilation and creation operators respectively, s is a complex parameter. The s’-ordered operator power-series expansion of s-ordered operator sa+mans in terms of the two-variable Hermite polynomial is also derived. Application of operators’s-ordering formula in studying displaced-squeezed chaotic field is discussed.     

Ultrafast nonlinear optical properties of dye-doped PMMA discs irradiated by 40 fs laser pulses

The two-photon absorption (TPA) characteristics of PMMA discs doped with three different dyes were studied using an fs-pulsed Ti-Sapphire laser as the pump source, and employing the open-aperture Z-scan technique. TPA cross-sections obtained for PMMA doped with the dyes PM597, DCM and rhodamine 6G–rhodamine B (co-doped) were found to be equal to 24.7, 33.3 and 32.3 GM, respectively (1 GM=10^?50 cm⁴ s phot^?1 mol^?1). Furthermore, two-photon fluorescence was measured for the samples containing DCM and rhodamine 6G–rhodamine B (co-doped). Compared to the one-photon fluorescence spectrum, the peaks in the two-photon fluorescence spectrum were red shifted and the extent of red shift increased with increasing doping concentration. We have also observed that the red shift in the two-photon fluorescence peak of the samples in the solid form is much larger than that in the solution state. This phenomenon could be explained by a twisted intra-molecular charge transfer model.     

Preparations for the study on the cluster structure of 16C

In order to look for a proposed cluster structure of 16C, simulation work was made. The simulation of the reaction dynamics give the resolution of the excitation energy on 16C which was reconstructed prior to breakup. The excitation energy resolution is typically ～200 keV at 2 MeV above the two body decay threshold for 16C→12Be+4He. Moreover,some performances of detectors tested using 241 Am α source are also reported.     

Preparation and characterization of Fe3O4 magnetic composite microspheres covered by a P(MAH-co-MAA) copolymer

A magnetic core–shell-layered polymer microsphere (MPS) was successfully synthesized by a dispersion polymerization route, where the modified Fe₃O₄ nanoparticles (MFN) were used as a core, while poly(maleic anhydride-co-methacrylic acid) P(MAH-co-MAA) as a shell was covered on the surface of the Fe₃O₄ nanoparticles. Environmental scanning electron microscope (ESME) and transmission electron microscope (TEM) measurements indicate that the magnetic P(MAH-co-MAA)/Fe₃O₄ composite microspheres assume sphericity and have a novel core–shell-layered structure. The crystal particle sizes of the unimproved Fe₃O₄ and the MFN samples vary from 8 to 16 nm in diameter, and the average size is about 10.6 nm in diameter. The core–shell magnetic composite microspheres can be adjusted by changing the stirring speed. Since multiple Fe₃O₄ cores were coated with a proper percentage of P(MAH-co-MAA) copolymers, and therefore lower density was acquired for the MPS, which improved sedimentation and dispersion behavior. The saturated magnetization of pure Fe₃O₄ nanoparticles reaches 48.1 emu g⁻¹ and the value for composite nanoparticles was as high as 173.5 emu g⁻¹. The nanoparticles show strong superparamagnetic characteristics and can be expected to be used as a candidate for magnetism-controlled drug release.     

2+1维de-Sitter时空中光线的轨迹

通过求解2+1维de-Sitter时空中零测地线方程得到光线的轨迹方程,对轨迹方程进行分析发现其不存在封闭的轨迹解.     

金属有机物化学气相沉积法生长Ga2(1-χ)In2χO3薄膜的结构及光电性能研究

采用金属有机物化学气相沉积(MOCVD)法在蓝宝石(0001)衬底上制备出了Ga2(1-χ)In2χO3(χ=0.1-0.9)薄膜,研究了薄膜的结构、电学和光学特性以及退火处理对薄膜性质的影响.测量结果表明:当In组分χ=0.2时,样品为单斜β-Ga2O3,结构;χ=0.5的样品,薄膜呈现非晶结构,退火处理后薄膜结构得到明显的改善,由非晶结构转变为具有(222)单一取向的立方In2O3结构;对于χ=0.8,薄膜为立方In2O3,结构,退火后薄膜的晶体质量得到提高.在可见光区薄膜本身的透过率均达到了85%以上,带隙宽度随样品中Ga含量的改变在3.76-4.43 eV之间变化,且经退火处理后带隙宽度明显增大.     

HL-2M偏滤器CFC/CuCrZr靶板的非晶钎焊工艺研究

在采用商用的STEMET-1101非晶钎料、温度为710~750°C的真空钎焊下,对CFC/OFC(氯氟烃/无氧铜)复合块与CuCrZr(铬锆铜)的钎焊进行了研究。首先,通过X-射线衍射(XRD)和差式扫描量热分析对钎料的结构和熔化行为进行了表征;然后,通过光学显微镜、电子探针微分析和拉伸试验等方法对焊缝的组织形貌、元素成分分布、相结构和力学性能进行了分析;最后,通过高热负荷装置对CFC/OFC/CuCrZr钎焊模块的热疲劳性能进行测试。结果表明,在710~750°C钎焊温度内焊缝由Cu固溶体、(Cu, Ni)3P和Ni(Cu ,Cr)2P金属间化合物组成,焊缝平整无裂纹;特别是在750°C/15min情况下,抑制了焊缝金属间化合物的连续分布,OFC/CuCrZr的焊接强度大于OFC的抗拉强度,CuCrZr/CuCrZr的结合强度为210MPa,并呈现部分韧性断裂。在750°C/15min情况下制备的CFC/Cu/CuCrZr模块可以承受1000次7MW·m^-2的循环热负荷。