中药黄柏主要活性成分的光谱成像检测技术

为了实现中药主要活性成分的在体检测,运用光谱成像技术检测中药活性成分.使用自行开发的液晶光谱成像装置对中药黄柏的主要活性成分盐酸小檗碱进行了在体检测,选取紫外光源波长254 nm,获取了检品480～700 nm之间的连续荧光光谱图像.在分析检品光谱剖面图的基础上,以中国药品生物制品检定所提供的盐酸小檗碱标准品的光谱剖面图为依据,设计了高通滤波器得到了检品的特征光谱数据.对八种不同来源的市售黄柏饮片特征光谱,以及黄柏与其同科植物黄皮特征光谱的比较显示,使用本方法对中药进行定性、定量的检测,样品无需特殊处理,可在原生态的情况下进行;检测过程无损、实时;检测结果指纹特征明显.     

Characteristics of deep penetration laser welding of dissimilar metal Ni-based cast superalloy K418 and alloy steel 42CrMo

Experimental trials of autogenous deep penetration welding between dissimilar cast Ni-based superalloy K418 and alloy steel 42CrMo flat plates with 5.0 mm thickness were conducted using a 3 kW continuous wave (CW) Nd:YAG laser. The influences of laser output power, welding velocity and defocusing distance on the morphology, welding depth and width as well as quality of the welded seam were investigated. Results show that full keyhole welding is not formed on both K418 and 42CrMo side, simultaneously, due to the relatively low output power. Partial fusion is observed on the welded seam near 42CrMo side because of the large disparity of thermal–physical and high-temperature mechanical properties of these two materials. The microhardness of the laser-welded joint was also examined and analyzed. It is suggested that applying negative defocusing in the range of Raylei length can increase the welding depth and improve the coupling efficiency of the laser materials interaction.     

在线单模光纤偏振控制器研究

利用Ｐｏｉｎｃａｒｅ球理论首次全面分析了在线全光纤偏振控制器。结果发现该偏振器可以有八种不同路径，实现任意偏振态之间的转化，最后通过实验验证了其工作性能。     

单重态氧发生器出口气流中水汽含量的光谱测量法

水汽的含量是化学法单重态氧发生器（ＳＯＧ）的重要性能参数之一，因为它不仅对Ｏ＿２（￣１△）有猝灭作用，而且在氧碘化学激光器（ＣＯＩＬ）光腔中对Ｉ￣＊也有严重猝灭作用。因此测控ＳＯＧ出口处的水汽含量有重要意义。本实验采用光谱强度比较法测量ＳＯＧ中的水汽含量，利用ＯＭＡ－３的二维扫描积累功能，可对不同测点的光谱进行同时扫描积累，从而可以对ＳＯＧ的数个测点同时进行水汽含量测定。测试精度可达±１０％。     

Thermoluminescence characteristics of rare-earth-doped LiCaBO3 phosphor

LiCaBO₃ was synthesized by high-temperature solid-state reaction. The influence of different rare earth dopants, i.e. Dy³⁺, Tb³⁺, Tm³⁺ and Ce³⁺, on thermoluminescence (TL) of LiCaBO₃ phosphor was discussed. We studied the TL properties and some dosimetric characteristics of Ce³⁺-activated LiCaBO₃ phosphor in detail. The effect of the concentration of Ce³⁺ on TL was investigated, the result of which showed that the optimum Ce³⁺ concentration was 1 mol%. The TL kinetic parameters of LiCaBO₃:0.01Ce³⁺ were studied by computer glow curve deconvolution (CGCD) method. The three-dimensional (3D) TL emission spectra were also studied, peaking at 431 and 474 nm due to the characteristic transition of Ce³⁺. We also studied the linearity, annealing condition, reproducibility, fading and different heating rate of the LiCaBO₃:0.01Ce³⁺ phosphor.     

PbS quantum dot fiber amplifier based on a tapered SMF fiber

A PbS quantum dot coated (QD-coated) tapered fiber amplifier with a broad bandwidth is theoretically demonstrated. The QD layer is coated on the surface of a tapered fiber and is excited by the evanescent wave of a pump. An optical gain of 10.5 dB, with a 160-nm broad bandwidth of at 1530-nm center wavelength, is achieved. The gain efficiency is over 4 dB/cm. This QD-tapered fiber amplifier has a concentration control of the QDs, a lower insertion loss, and shows good suppression of amplified spontaneous emission (ASE), while its structure is also quite simple. Therefore, the proposed fiber amplifier has great potential in fiber-optic communication systems.     

Discovery of a nuclear isomer in 65Fe with penning trap mass spectrometry

A new long-lived isomeric state in (65)Fe has been discovered with Penning trap mass spectrometry and high-precision mass measurements of the neutron-rich isotopes (63-65)Fe and (64-66)Co have been performed with the Low-Energy Beam and Ion Trap Facility at the NSCL. For the new isomer in (65)Fe an excitation energy of 402(5) keV has been determined from the measured mass difference between the isomeric and ground states. The mass uncertainties of all isotopes have been reduced by a factor of 10-100 compared to previous results. In the case of (64)Co the previous mass value was found to deviate by about 5 standard deviations from the new measurement.     

Synthesis of Polyaniline Submicrometer-Sized Tubes with Controllable Morphology

Polyaniline submicrometer-sized tubes with controllable morphology have been synthesized by chemical oxidative polymerization of aniline with the aid of sodium dodecylbenzenesulfonate. The products were characterized by field-emission scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy, respectively. The effects of the concentrations of sodium dodecylbenzenesulfonate, reaction temperatures and growth conditions on the morphologies of polyaniline submicrometer-sized tubes have been investigated.