Multifunctional high-performance l O-J level laser system

In this letter, we report a multifunctional high-performance Nd：glass laser system. Laser pulses from an all-fiber front end are first amplified by a regenerative amplifier to 10 mJ level, and then further amplified in a four-pass amplifier. The laser system can provide 10.3-J, 3-ns laser pulses at 1053-nm wavelength. The shot-to-shot energy stability is better than 1.5% （RMS）. The output laser beam is near diffraction limit. Binary amplitude masks are used to maintain a flat top near-field profile with a 71% fill factor. After the frequency conversion process, 7 and 5.5 J pulses at 526.5 and 351 nm are obtained, respectively.     

随机微分方程大偏差的一个稳定性结论及其应用

本文证明了对可能退化的扰动泛函型随机微分方程,其漂移项增加适当的扰动不改变大偏差性质。该结果应用于漂移系数在一个超曲面上跳跃的退化扩散过程。     

Simple proof of a large deviation result

In this note we prove the large deviation principle for the following process in R:dxt = b(xt, t)dt edwt, t E [0, 1], (1)where the initial point xo is fixed, wt is a Wiener process5 E > 0 is a small parameter whichtends to 0, b(x, t) is a bounded piecewise Lipschitz function of the form(b (x, t), x > 0t,b(xlt)={b--(::t)i x<0jf (2)where e is a smooth curve, bf are two bounded Lipschitz functions on (--oo, co) x [0, oo)satisfyingb--(0t, t) 2 b (0t, t). (3)If (3) is replaced with an opposite …     

Towards deep‐blue phosphorescence: molecular design and property prediction of iridium complexes with pyridinylphosphinate ancillary ligand

A series of iridium complexes ( 1 – 5 ), which consist of two 2‐(2,4‐difluorophenyl)pyridine (dfppy)‐based primary ligands and one pyridinylphosphinate ancillary ligand, have been investigated theoretically for screening highly efficient deep‐blue light‐emitting materials. Compared with the reported dfppy‐based emitter 1 , the designed iridium complexes 3 – 5 with the introduction of a stronger electron‐withdrawing (–CN, –CF₃ , or o‐carborane) group and a bulky electron‐donating (tert‐butyl) group in dfppy ligands can be achieved to display the emission peaks at 443, 442, and 447 nm, respectively. The electronic structures, absorption and emission properties, radiative and nonradiative processes of their excited states, and charge injection and transport properties of the iridium complexes are analyzed in detail. The calculated results show that designed iridium complexes have comparable radiative and nonradiative rate constants with 1 , and are expected to have similar quantum efficiency with 1 . Meanwhile, these designed complexes keep the advantages of the charge transport properties of 1 , indicating that they are potential iridium complexes for efficient deep‐blue phosphorescence. This work provides more in‐depth understanding the structure–property relationship of dfppy‐based iridium complexes, and shed lights on molecular design for deep‐blue phosphorescent metal complexes.     

PLS–分光光度法同时测定三组分阳离子染料

将偏最小二乘法用于可见分光光度分析,建立一种同时测定阳离子黄X–8GL、阳离子红X–FG、阳离子艳蓝RL三组分混合染料含量的新方法。在380～780 nm范围内,将测定的26组混合溶液的吸光度值作为校正集,另8组混合溶液的吸光度值作为预测集,结合二阶差分法确定最佳主成分数。测得三组分混合体系中校正集的相关系数分别为0.9988,0.9994,0.9964;交互验证均方根误差(RMSECV)分别为0.0754,0.1852,0.2168;预测集的相关系数分别为0.9984,0.9996,0.9981;预测均方根误差(RMSEP)分别为0.1086,0.1877,0.2515。该方法无需样品分离,可为染色过程中多组分染料浓度的在线监测提供技术支撑。     

A colorimetric probe for the rapid and selective determination of mercury(II) based on the disassembly of gold nanorods

We report on a novel mercury(II)-controlled approach for the disassembly of gold nanorods (AuNRs) that has led to a detection system for Hg(II). The modified AuNRs were fabricated by functionalizing AuNRs with L-cysteine via a thiol group chemisorption-type of interaction. L-cysteine induces the assembly of AuNRs through cooperative electrostatic interaction upon which the color of the solution of the AuNRs changes from blue-green to gray dark. The addition of Hg(II), in turn, causes the disassembly of the modified AuNRs and the color of the solution returns to blue-green. This effect enables the optical determination of Hg(II) in aqueous solution, with a linear response in the 0.5 to 250 μM Hg(II) concentration range, an excellent selectivity for Hg(II), and with recoveries ranging from 99 % to 106 % in spiked environmental water samples.

阿司匹林合成体系三组分的拉曼光谱测定及应用

阿司匹林合成过程中所采集的阿司匹林、水杨酸和乙酸酐的拉曼光谱存在交迭现象,很难从光谱数据中分离各组分含量。根据反应体系的组成和浓度配制样本溶液并采集拉曼光谱,运用多种方法对光谱进行预处理结合偏最小二乘法（PLS）对混合体系中阿司匹林、乙酸酐和水杨酸3组分浓度和光谱矩阵建立回归模型,对回归结果进行比较,根据交互验证均方根误差RMSECV,预测相关系数帮,预测均方根误差RMSEP。结果表明预处理方案可以有效降低基线漂移对预测精度的影响,根据Q值检验法和严检验法确定经矢量归一＋Savitzky-Golay五点二次平滑一阶卷积求导＋均值中心化对拉曼光谱预处理,PLS主成分选4,交互验证选用“逐一法”可时阿司匹林反应体系3组分进行同时测定,此训练集为阿司匹林合成体系的拉曼光谱在线监测提供了良好的数据支持。     

Conducting polymer nanostructures and their application in biosensors

Nowadays, functionalized conducting polymer nanomaterials have been received great attention in nanoscience and nanotechnology because of their large surface area. This article reviews various methods for synthesis of conducting polymer nanostructures and their applications in sensing materials, focusing on hard-template, soft-template and other methods and the formation mechanism of conducting polymer nanostructures by these methods. Conducting polymer nanostructures, such as nanotubes, nanowires, and nanoparticles, as sensing platforms for various applications are also summarized.