BODIPY-based fluorometric sensor array for the highly sensitive identification of heavy-metal ions

A BODIPY(4,4-difluoro-4-bora-3a,4a-diaza-s-indacene)-based fluorometric sensor array has been developed for the highly sensitive detection of eight heavy-metal ions at micromolar concentration. The di-2-picolyamine (DPA) derivatives combine high affinities for a variety of heavy-metal ions with the capacity to perturb the fluorescence properties of BODIPY, making them perfectly suitable for the design of fluorometric sensor arrays for heavy-metal ions. 12 cross-reactive BODIPY fluorescent indicators provide facile identification of the heavy-metal ions using a standard chemometric approach (hierarchical clustering analysis); no misclassifications were found over 45 trials. Clear differentiation among heavy-metal ions as a function of concentration was also achieved, even down to 10⁻⁷ M. A semi-quantitative interpolation of the heavy-metal concentration is obtained by comparing the total Euclidean distance of the measurement with a set of known concentrations in the library.     

A highly selective fluorescent probe for the detection of palladium(II) ion in cells and aqueous media

We report on a fluorescent probe for the optical (and even bare eye) detection of palladium(II) ion which causes the probe to undergo a strong increase in absorbance and fluorescence. The probe is easily synthesized from rhodamine B hydrazide and 9-anthraldehyde and displays high selectivity over other metal ions. Fluorescence intensity and absorbance are linearly proportional to the concentration of Pd(II) in the 0–7 μM and 0–1 μM concentration range, respectively, with detection limits of 0.21 μM and 0.03 μM. The probe can detect Pd(II) with virtually no interferences by other metal ions and anions. It was applied to intracellular imaging of Pd(II) in living cells and to its determination in a palladium-containing catalyst and in spiked water samples.

A further work on multi‐phase two‐fluid approach for compressible multi‐phase flows

This paper is to continue our previous work Niu (Int. J. Numer. Meth. Fluids 2001; 36 :351–371) on solving a two‐fluid model for compressible liquid–gas flows using the AUSMDV scheme. We first propose a pressure–velocity‐based diffusion term originally derived from AUSMDV scheme Wada and Liou (SIAM J. Sci. Comput. 1997; 18 (3):633—657) to enhance its robustness. The scheme can be applied to gas and liquid fluids universally. We then employ the stratified flow model Chang and Liou (J. Comput. Physics 2007; 225 :240–873) for spatial discretization. By defining the fluids in different regions and introducing inter‐phasic force on cell boundary, the stratified flow model allows the conservation laws to be applied on each phase, and therefore, it is able to capture fluid discontinuities, such as the fluid interfaces and shock waves, accurately. Several benchmark tests are studied, including the Ransom's Faucet problem, 1D air–water shock tube problems, 2D shock‐water column and 2D shock‐bubble interaction problems. The results indicate that the incorporation of the new dissipation into AUSM⁺‐up scheme and the stratified flow model is simple, accurate and robust enough for the compressible multi‐phase flows. Copyright © 2008 John Wiley & Sons, Ltd.     

双光子阵列点激发同时多维荧光信息的处理

五维同时荧光信息显微成像方法是一种新的荧光信息获取技术，它采用了双光子阵列点激发方式.这一方法可同时获取激发阵列点每点荧光的位置信息、荧光光谱信息和荧光寿命信息，弥补了现有荧光检测技术的不同功能信息不具有同时性的缺陷.给出了从这种技术的复合信息中提取复合光谱几何强度结构图像、不同光谱几何强度结构图像、不同光谱寿命图像的方法.提出了一种激发荧光强度修正系数矩阵方法，消除阵列点激发光强不均匀对激发荧光强弱产生的不利影响，取得明显效果.实验对实际样品做了数据采集和处理，给出图像结果，表明处理的效果良好.对存在的问题也作了讨论. 关键词： 荧光信息处理 双光子 荧光光谱 荧光寿命     

激光加工技术的应用及其发展趋势

本文简单地综述了激光加工技术开发与应用情况,简介了激光相变硬化、激光施釉、激光退火、激光包层、激光表面合金化、激光切割和打孔、受激准分子激光加工等应用技术,还介绍了激光加工技术的发展趋势。     

A Mössbauer investigation of the amorphous Tin-Antimony oxide films

The Tin-Antimony oxide films SN_1-xSb_xO₂ (x=0.00-0.66) with thickness about 1100Å have been prepared on glass substrates by CVD and studied by using CEMS and XRD. The broad line widths of Mössbauer spectra and of X-ray diffraction patterns indicate a distribution of the hyperfine parameters due to the distortion of the rutile lattice. A distribution fitting program has been used to evaluate the distribution of quadrupole splitting QS and of isomer shift IS in the samples studied.     

Preparation, characterization and magnetic properties of disubstituted ternary heteropolyoxometalates [TBA]3H n [PW9MoM2-O38(H2O)2]· 3C3H6O(TBA = tetrabutylammonium, M = transition metal)

Summary The half Wells-Dawson structure complex Na₉PW₈-MoO₃₄·11H₂O has been prepared by reaction of Na₂WO₄·2H₂O, Na₂MoO₄·2H₂O and KH₂PO₄ in water. A series of transition metal substituted heteropolyoxometalate complexes with ternary Keggin structures of the general formula [TBA]₃H _n [PW₉MoM₂O₃₈ (H₂O)₂]·3C₃H₆O (TBA = tetrabutylammonium; n = 2, M = Fe³⁺; n = 4, M = Mn²⁺,Co²⁺,Cu²⁺or Zn²⁺), have been synthesized using Na₉PW₈MoO₃₄·11H₂O and the transition metal nitrate as the starting materials in aqueous solution. The compounds were characterized by elemental analyses and spectroscopy. X.p.s. data indicate that the binding energies of all the elements in the title compounds are lower than those in similar compounds. The magnetic susceptibilities of the compounds reveal antiferromagnetic properties.     

Dy-BPMPHD一CTMAB荧光 体系的研究及其分析应用

本文对伪-BPMPHD-CTMAB荧光体系进行了研究.研究发现，Dya+能与BPMPHD和CTMAB形成离子缔合物，并发射出伪3t的特征荧光峰.}3十、Y'+ , Lu’十离子能增强体系的荧光强度，产生共发光效应.本文对该共发光体系进行了详细研究，由此提出了快速、灵敏测定痕量稀土伪3t的新方法，其测定线性范围为1.0X1。一’-1. 3X 10-Smol/L,检出限为2. 0X 10-enrol/L     

Mucin: Aggregation and colloidal interactions of relevance to some biomedical problems

Summary Mucus is the viscoelastic secretion that lines, most epithelial surfaces forming a protective, lubricating barrier. The viscoelastic properties of mucus arise from mucin, a glycoprotein of molecular weight ranging from 2–10 million. In this paper we address two problems where the aggregation and interactions of mucin with colloidal particles is of physiological relevance. The first deals with gastric mucin and the question of the mechanisms that prevent the stomach from digesting itself. Using dynamic light scattering techniques we show that solutions of gastric mucin aggregate belowpH 4. Very large aggregates with 100-fold slower diffusion constants than the mucin monomer are observed atpH 2. Viscosity measurements indicate that mucin will eventually gel at lowpH, thus acting as a diffusional, barrier and protecting the stomach. The second problem is concerned with the role of mucin in the nucleation of cholesterol crystals which lead to gallstone formation. Using dynamic light scattering we have shown that mucin at relatively low concentrations (4 mg/ml) promotes the fusion of phospholipid + cholesterol vesicles. The time evolution of the fusion process was measured. No changes in the aggregation state of the gallbladder mucin were observed during the fusion process, suggesting that this phenomenon is related to physico-chemical interactions between the polymer (mucin) and the colloidal particle (vesicle). Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994.     

均衡功率的超宽带可调谐掺铒光纤激光器

报道了一种功率均衡的超宽带可调谐掺铒光纤激光器.该激光器采用窄线宽可调谐FP滤波器、掺铒光纤、波分复用器和耦合器构成光纤环形腔激光器，并通过部分反馈光功率自动控制，对输出激光功率进行均衡.实现了87 nm带宽（1525~1612 nm）范围内，输出激光功率波动小于0.2 dB的均衡结果.输出激光3 dB线宽为0.26 nm，边模抑制比大于55 dB.