外科植入物用不锈钢金相试样的制备

对外科植入物不锈钢试样的制备进行了试验。结果表明，牙托树脂具有最佳的凝固速度和可填充性，可用手捏成任意的形状，使试样可任意地被压入或被包住，可做到试样镶嵌的随意性，尤其适合细丝和薄板的镶嵌；试面抛光选用非压敏胶植绒型抛光布，抛光效果好，可准确评定夹杂物；选用王水做侵蚀试剂，用擦拭的方法可有效地显示游离铁素体和其显微组织。     

Hybrid transistor manipulation controlled by light within a PANDA microring resonator

In this paper, the novel type of transistor known as a hybrid transistor is proposed, in which all types of transistors can be formed by using a microring resonator called a PANDA microring resonator. In principle, such a transistor can be used to form for various transistor types by using the atom/molecule trapping tools, which is named by an optical tweezer, where in application all type of transistors, especially, molecule and photon transistors can be performed by using the trapping tools, which will be described in details.     

Colour Transparencies on Coloured Supports

When transparencies are to be viewed by light, the colour of which does not appear to be perfectly white, pictures of better quality can be obtained by coating the film on coloured base; in the case of transparencies to be viewed by tungsten-light projectors the base would be coloured bluish. By making the base coloured instead of having image layers which produce coloured gray scales, consistency of perceived colour balance can be achieved at the lowest densities as well as at other densities. Reduced halation and less edge-fog for those colours absorbed by the base colour are additional advantages.     

红外序列图像中热晕背景的消除

红外探测器工作时间长或太阳直射时,可观察到红外图像有热晕现象。红外探测器观察的 景物亮度或对比度通常很低,此时热晕对红外像质的影响比较严重。针对上述情况,研究用数字图像处理的方法——帧相减、反色相加,对红外图像进行实时背景补偿,以便消除热晕的影响。在此基础上用数学形态学去除图像中的噪声点,突出目标。理论和实验结果表明,对红外图像的热晕补偿改善了图像的质量。     

Alternating-layered spherulites in thin-film poly(trimethylene terephthalate) by stepwise crystallization schemes

Structuring of multi-layered spherulites in aryl polyester of poly(trimethylene terephthalate) (PTT) by stepwise crystallization was attempted. Characterization of feasibility was performed by polarized-light microscopy (POM), differential scanning calorimetry (DSC), and wide angle X-ray diffraction (WAXD). Two- or three-layered spherulites could be developed in PTT by subjecting to stepwise crystallization. Sequence and number of layers in spherulites can be designed by altering the steps of temperatures with proper holding time. Time must be allocated properly in the multiple steps if three different textures are to be structured into one single PTT spherulite by stepwise crystallization. Coexistence of multiple lamellar thicknesses and various degrees of crystal perfection were supported by DSC results. The various crystalline regions of the layered spherulites in PTT develop upon stepwise crystallization exhibit the same unit cell as demonstrated by WAXD crystallographs.     

The connection between Bell's inequalities based on probabilities and those based on correlations

Abstract

Violation of Bell inequalities is widely regarded as a definitive test for non-locality. However, Bell correlational inequalities must always be satisfied by all jointly present, cross-correlated data. The correlations of variable pairs obtained in repeated runs are not cross-correlated in this way and are not required to satisfy the Bell inequality. In addition, by using information regarded as non-local, proper joint correlations may be computed among counterfactual and measured variables. These correlations satisfy the Bell inequality, but are spatially non-stationary in angle. By using a simple symmetry condition, such considerations may be extended to inequalities in probabilities. The latter may be derived directly from correlational inequalities developed by Clauser, Horne, Shimony and Holt (CHSH). Violation of either correlational or probabilistic Bell inequalities then implies that the Bell correlation cannot be accounted for by a stochastic process that is spatially stationary in angle coordinates. However, other processes may still be allowed.     

The internal structure of diamond by electrostatic charging in the SEM

The internal structure of both natural and synthesized diamonds can be revealed in great detail by electrostatic charging in the electron beam in a SEM. Closely spaced growth rings can be resolved by this simple technique which should be useful for characterizing diamonds for several applications.     

Werkstoffauswahl für schlagartig und zyklisch belastete metallische Bauteile

Material Selection for Impact and Fatigue Loading The structural durability of components is dominated mainly by the geometry, i.e. notches. Compared with the impact resistance of forged components from ductile materials high impact values can be realized by an appropriate shaping also using less ductile cast materials. Creep deformations can be suppressed in presence of notches. The strength level of the base material remains for stress concentrations above K_t = 2.5 and for the welded state without influence on the fatigue behaviour. If sharp notches cannot be avoided by a new design, benefits from high‐strength materials can be taken only in connection with surface treatments which introduce high compressive residual stresses. Principally, advantages from high‐strength materials can be gained for unwelded components only by reduction of the stress‐concentration and in case of welded joints by smoothening or removal of the weld notches and in case of spot welds by transferring of the failure location outside of the nugget.     

Chemical amplification — A novel approach to ultratrace analysis

The lowest concentration that can be estimated with 100% error in chemical analysis by instrumental technique is referred to as detection limit. It is equal to the ratio of twice the background signal to the magnitude of analytical signal corresponding to a concentration of unity. Detection limit (dl) could be improved if the analytical signal alone could be selectively amplified without affecting the background. It is shown that this could be achieved by chemical amplification. Atomic amplification of two or three orders of magnitude could be obtained by combining two chemical amplifications in series. It is demonstrated that by using heteropoly acid formation as the first amplification reaction and determining molybdenum in the heteropoly acid by catalyticdc polarographic wave, a detection limit for the hetero atom of less than a ppb can be obtained. It is pointed out that the approach of selectively amplifying analytical signals by tandem chemical amplification reactions makes it possible to perform ultratrace analysis (ppb level) with classical instrumental analytical techniques which havedl at ppm level.     

Nonaging cold-pressed SmCo5magnets

The origin of the aging of SmCo5magnets is shown to be the reaction with adsorbed air. This reaction can be avoided by excluding all oxygen during the preparation. It is shown that by deformation pressing, nonaging magnets can be made because they are dense enough to avoid oxygen penetration. The adsorbed oxygen reacts with Sm during sintering which results in the formation of undesirable Sm2O3. The formation of these oxides can also be avoided by preparing the samples in oxygen-free atmospheres. During deformation pressing theIHcof the powder decreases considerably; this problem can be solved by using hydrogen-ground powder which has a very high coercive force.     

板结构静载荷的损伤检测算法

在四周固支板结构上施加一个静载荷,求所测得的应变向量的单位向量,该单位向量与载荷大小无关,与加载位置有关,称为"模式".根据有限元理论,当某个单元出现了损伤,损伤对应变场的影响相当于一些附加载荷作用在完好结构上,且这些附加载荷作用在损伤所在的单元节点上.损伤检测的问题就成为多载荷识别问题.将损伤前后的模式进行相关分析,可以识别附加载荷位置,判别加载点是否是损伤位置.通过在结构上逐点加载,可以发现结构上出现的所有损伤.     

压力模拟试验过程中引压管路标定方法研究

压力模拟试验通过精准控制试件附近压力的变化,模拟出试验件在实际工作过程中的气流环境,考察试验件通气效能及结构可靠性。文章结合试验过程中测量特定位置压力值的需求,提出一种引压管路测压的标定方法。在标定试验中,使用测量规通过引压管路得到初始压力值,用标准真空规得到待测位置的标准压力值。利用MATLAB选择合适的拟合函数并将两组数值拟合出一组修正关系式,后续试验中将测量规的压力值通过关系式修正即可得出待测位置的准确压力值。经试验验证,该标定方法能够有效消除引压管路对压力测量值的影响,保证压力模拟试验的顺利进行。     

Polyethyelene Glycols and Drug Release

The dissolution rates of several drugs may be increased by incorporation into solid polyethylene glycols1. These dispersions are usually manufactured by heating a physical mixture of the drug and polymer to the fluid state and subsequently cooling to room temperature.

The physical structure of both the drug and the polyethylene glycol will be discussed, as these factors may affect the rate of drug release from the dispersions2,3. The solid state properties of both components have traditionally been studied by X-ray diffraction and/or by differential scanning calorimetry (DSC). The latter technique has facilitated the use of phase diagrams in the investigation of the melting properties of the dispersions, these usually indicating the presence of eutectics, monotectics, solid solutions or glasses. The application of a further technique, dielectric spectroscopy, in the study of molten and solid dispersions will be described.

The mechanisms by which drug dissolution rate may be enhanced will be described. Furthermore, the kinetics of drug release will be discussed in terms of the non-interactive and interactive models proposed by Corrigan4.     

Dispersion of micelle-encapsulated fluorophores in a polymer matrix for control of color of light emitted by light-emitting diodes

In the present study, we demonstrated that fluorescent dyes could be nanoscopically dispersed in a polymer matrix that was immiscible with the dyes; the dyes were encapsulated in micelles. Using a model polymer composite, we also showed that the color of light emitted by light-emitting diodes (LEDs) could be controlled by coating fluorescent polymer composites onto the LEDs. For this purpose, fluorophores that were insoluble in toluene were solubilized into a solution of block copolymer micelles in toluene by the selective incorporation of fluorescent dyes into micellar cores. Because the micelles could be dispersed well in the polymer matrix without the formation of aggregates, fluorescent dyes encapsulated in the micelles were also effectively dispersed in the polymer matrix without macroscopic separation. The polymer composite can be evenly coated onto most substrates, regardless of their surface characteristics. Thus, light-emitting devices with well-controlled emission wavelengths and emission intensities can be fabricated by coating the polymer composite onto the surface of the device.     

Die Relativierung des Spannungsbegriffes in der zerstörenden Materialprüfung

Relativity of the notion “stress” in destructive materials testing. Later developments of certain important fields in destructive testing can be correlated with the modification undergone by the notion of stress in its practical application: In connection with highly elastical and plastical deformation this notion becomes more and more relative because of its dependence on the time scale of the test; in the field of random loading the idea of a maximum tolerable stress has to be replaced by the algorythmic handling of irregular loading histories; in fracture mechanics stress can no longer be considered independently and has to be linked to influences of local distortions. Both random fatigue and fracture mechanics can by no means be regarded as entirely solved problems. Some directions are discussed in which the answers to open questions might be found. Some consequences for the conception of new testing equipment are mentioned.     

Fourier-transform method of phase-shift determination

A new phase-shifting interferometry analysis technique has been developed to overcome the errors introduced by nonlinear, irregular, or unknown phase-step increments. In the presence of a spatial carrier frequency, by observation of the phase of the first-order maximum in the Fourier domain, the global phase-step positions can be measured, phase-shifting elements can be calibrated, and the accuracy of phase-shifting analysis can be improved. Furthermore, reliance on the calibration accuracy of transducers used in phase-shifting interferometry can be reduced; and phase-retrieval errors (e.g., fringe print-through) introduced by uncalibrated fluctuations in the phase-shifting phase increments can be alleviated. The method operates deterministically and does not rely on iterative global error minimization. Relative to other techniques, the number of recorded interferograms required for analysis can be reduced.     

带有余弦函数的三维混沌弱信号检测系统及电路实现

从理论上分析了二维Duffing弱信号检测系统变量输出在混沌和周期态之间交替转换。发现一种新的三维混沌弱信号检测系统生成规则,以生成4种检测系统之一的三维Liu-cos混沌系统为例,采用傅里叶变换等方法从理论上验证了新生成的三维混沌弱信号检测系统输出信号具有广域收敛性,解决了二维Duffing混沌弱信号检测系统不能广域检测和输出信号不收敛问题;新设计的三维Liu-cos混沌弱信号检测电路空中声波实验显示可抗低频声波干扰,检测性能优于二维Duffing混沌电路和新设计的Duffing＋滤波器电路,水中实验显示三维Liu-cos混沌弱信号检测电路可抗高频水声干扰,可检测波形畸变的水声信号。     

Continuous electrophoretic purification of individual analytes from multicomponent mixtures

Individual analytes can be isolated from multicomponent mixtures and collected in the outlet vial by carrying out electrophoretic purification through a capillary column. Desired analytes are allowed to migrate continuously through the column under the electric field while undesired analytes are confined to the inlet vial by application of a hydrodynamic counter pressure. Using pressure ramping and buffer replenishment techniques, 18% of the total amount present in a bulk sample can be purified when the resolution to the adjacent peak is approximately 3. With a higher resolution, the yield could be further improved. Additionally, by periodically introducing fresh buffer into the sample, changes in pH and conductivity can be mediated, allowing higher purity (>or=99.5%) to be preserved in the collected fractions. With an additional reversed cycle of flow counterbalanced capillary electrophoresis, any individual component in a sample mixture can be purified providing it can be separated in an electrophoresis system.     

化学还原法制备纳米铜粉的研究

本文采用KBH4在液相中化学还原CuSO4,并加入KOH和络合剂EDTA ,制得了纳米级的纯净的铜粉 ,通过调整反应物的浓度 ,可以消除Cu2 O等杂质。制备的纳米铜粉还存在一定程度的团聚 ,需试验加入分散剂来改善。     

Polyethyelene Glycols and Drug Release

Abstract

The dissolution rates of several drugs may be increased by incorporation into solid polyethylene glycols1. These dispersions are usually manufactured by heating a physical mixture of the drug and polymer to the fluid state and subsequently cooling to room temperature.

The physical structure of both the drug and the polyethylene glycol will be discussed, as these factors may affect the rate of drug release from the dispersions2,3. The solid state properties of both components have traditionally been studied by X-ray diffraction and/or by differential scanning calorimetry (DSC). The latter technique has facilitated the use of phase diagrams in the investigation of the melting properties of the dispersions, these usually indicating the presence of eutectics, monotectics, solid solutions or glasses. The application of a further technique, dielectric spectroscopy, in the study of molten and solid dispersions will be described.

The mechanisms by which drug dissolution rate may be enhanced will be described. Furthermore, the kinetics of drug release will be discussed in terms of the non-interactive and interactive models proposed by Corrigan4.