微波炉在流动注射体系中的在线应用

微波炉在流动注射体系中的在线应用是近１０年来发展的一项新技术，在样品的在线分解和加速流动注射分析中指示反应速度方面获得广泛应用。本文从仪器技术、结果和应用几个方面概述了从１９８６年以来这项技术的发展。     

Assessing crystalline lamellae orientation impact on the properties of semi‐crystalline polymer‐clay nanocomposites

Semi‐crystalline polymer‐clay nanocomposite properties are often considered only by their clay dispersion state. The purpose of this work is to highlight texture effects on semi crystalline polymer‐clay properties. Maleic anhydride‐grafted polyethylene nanocomposites with two different processing techniques (Blown Extrusion and Compression) were studied. The processing was shown to induce different crystalline lamellae orientation in the films but with no significant changes in the crystalline lamellae long period, degree of crystallinity, clay particle orientation morphology and dispersion. The impact of these specific textures on the nanocomposites barrier and tensile properties were reported. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1966–1975, 2008     

具临界Sobolev指数的半线性椭圆方程的多重正解

本文讨论了零边值半线性椭圆方程的多重正解，其中使用没有（ＰＳ）条件的山路引理及对最佳Ｓｏｂｏｌｅｖ嵌入常数的分析，证明了至少两个解的存在性．     

On-line small-angle and wide-angle x-ray scattering studies on melt-spinning poly(vinylidene fluoride) tape using synchrotron radiation

On-line small-angle and wide-angle x-ray scattering experiments were performed during the melt spinning of polyvinylidene fluoride using the DESY synchrotron light source. In these studies, the melt-spinning apparatus consisting of a screw extruder, a metering pump, and a take-up motor system were assembled on two separate stepper-motor-driven platforms. To investigate the structure development during crystallization, the tape location at the desired distance from the die could be positioned at the beam level with synchronous vertical movement of extruder and take-up platforms. Small-angle and wide-angle x-ray patterns were taken simultaneously with a two-dimensional wire detector and one-dimensional wire detector. In a separate study, two-dimensional WAXS data were also taken under identical processing conditions to observe the off-equator diffraction behavior during the crystallization. The data obtained for a variety of take-up speeds generally indicate that SAXS d-spacings first appear large in the early stages of crystallization and gradually decrease along the spin-line (as the crystallization progresses). As the take-up speed increases, the crystallization onset position moves away from the die and d-spacings observed at the onset increase. In addition, the shape of the discrete scattering pattern starts as a meridional streak and converts to a teardrop shape with the tip of the pattern pointing toward the beam stop at the early stages of crystallization for high take-up speeds. This does not occur at low take-up speeds and is attributed to the differences in crystallization behavior which is spherulitic or sheaflike to row nucleated crystallites. Our studies also showed that SAXS patterns appear earlier than the wide-angle crystalline diffraction peaks indicating the SAXS technique to be more sensitive to the structural changes at these stages. An idealized model is developed to explain the observed patterns at high take-up speeds. This consists of two regimes. In regime 1, the periodic fluctuations due to the alternating crystalline and amorphous regions form along the regions where eventually the “shish” structures develop. In the second stage, a volume filling crystallization takes place between the existing crystallites along the shish structure and simultaneously radial overgrowth of crystallites (i.e., the “kebabs”) takes place. This causes the observed reduction in the average d-spacing. © 1993 John Wiley & Sons, Inc.     

求解交变载荷下异形板动力响应的Gurtin半解析法

该方法以Ｇｕｒｔｉｎ变分原理为基础，在空间域作有限元离散，时间域取级数。本文研究了在交变载荷ｑ（ｘ，ｙ，ｔ）＝Ｐ（ｘ，ｙ）ｓｉｎωｔ作用下任意形状板时域级数的取法，使得各种支承条件的动力响应问题均可由本计算模式得到具有相当精度和效率的解。     

Highly sensitive differential pulse amperometric detection of second generation anti-tumor platinum compounds in HPLC effluents

Summary A highly sensitive on-line amperometric detection of platinum compounds in HPLC effluents was possible with the use of a polarographic detector. For TNO-1 (=cis-1,1-di(aminomethyl)-cyclohexane Pt(II)chloride) a linear dynamic range of at least three decades could be obtained (0.034–108g TNO-1/ml) with a detection limit of three times the noise signal at 0.7 ng TNO-1 (20ng Pt/ml). The sensitivity was 0.1 nA/ng TNO-1 (0.2nA/ng Pt). The within-day presicion was 1.1% at a concentration of 10.8g TNO-1/ml (n=10). With this system the compatibility was measured of TNO-6 with infusion fluids. In 0.15 M NaCl, TNO-6 (=cis-1,1-di(aminomethyl)-cyclohexanePt(II)sulphate) was converted into TNO-1 within 40 minutes. Molecular changes of TNO-6 were also observed in a 5% aqueous glucose solution.     

A Flexible On-line Scheduling Algorithm for Batch Machine with Infinite Capacity

We study on-line scheduling on a batch machine with infinite capacity. We present a flexible on-line scheduling algorithm that aims at minimizing the makespan and achieves the optimal competitive ratio of . This research is substantially supported by a grant from City University of Hong Kong (Grant No. 7001119). The second author is supported by this grant and by the Natural Science Foundation of China.     

Optical Measuring Method for Quality Monitoring Purpose in Laser Welding of Tin－plates

ＯｐｔｉｃａｌＭｅａｓｕｒｉｎｇＭｅｔｈｏｄｆｏｒＱｕａｌｉｔｙＭｏｎｉｔｏｒｉｎｇＰｕｒｐｏｓｅｉｎＬａｓｅｒＷｅｌｄｉｎｇｏｆＴｉｎ－ｐｌａｔｅｓ￥ＬＵＯＨｏｎｇ；ＨＵＬｕｎｊｉ；ＨＵＡＮＧＳｈｕｈｕａｉ；ＬＩＺｈｉｙｕａｎ；ＨＵＸｉｙｕａｎ（Ｈ...     

Involutions in split semi‐quaternions

A map is an involution (resp, anti‐involution) if it is a self‐inverse homomorphism (resp, antihomomorphism) of a field algebra. The main purpose of this paper is to show how split semi‐quaternions can be used to express half‐turn planar rotations in 3‐dimensional Euclidean space and how they can be used to express hyperbolic‐isoclinic rotations in 4‐dimensional semi‐Euclidean space . We present an involution and an anti‐involution map using split semi‐quaternions and give their geometric interpretations as half‐turn planar rotations in . Also, we give the geometric interpretation of nonpure unit split semi‐quaternions, which are in the form p = coshθ + sinhθ i + 0 j + 0 k = coshθ + sinhθ i , as hyperbolic‐isoclinic rotations in .     

受迫振动实验中几个问题的探讨

就受迫振动实验中振动系统半宽带、品质因素及稳定受迫振动强迫力与阻力做功进行研究和探讨。