双波长标准加入法同时测定合金钢中钼和钨

在金属离子显色体系中,采用双波长分光光度法同时测定了合金钢中的钼和钨。对显色反应和光度测定的最佳条件进行了详细考察。在介质盐酸浓度为０．６～１．２ｍｏｌ／Ｌ,ＳＡＦ质量浓度为２０～６０ｍｇ／Ｌ,ＣＴＭＡＢ质量浓度为０．１８～０．４２ｇ／Ｌ的显色体系中,能够形成Ｗ－ＳＡＦ－ＣＴＭＡＢ和Ｍｏ－ＳＡＦ－ＣＴＭＡＢ络合物,吸光度值高且稳定。根据两络合物的吸收光谱,选择钼作为标准加入组分,在钨的等吸收点波长     

Prediction of Early Atherosclerotic Plaques Using a Sequence-Activated Fluorescence Probe for the Simultaneous Detection of γ-Glutamyl Transpeptidase and Hypobromous Acid

Atherosclerosis is a lipoprotein-driven disease, and there is no effective therapy to reverse atherosclerosis or existing plaques. Therefore, it is urgently necessary to create a noninvasive and reliable approach for early atherosclerosis detection to prevent initial plaque formation. Atherosclerosis is intimately associated with inflammation, which is accompanied by an excess of reactive oxygen species (ROS), leading to cells requiring more glutathione (GSH) to resist severe oxidative stress. Therefore, the GSH-hydrolyzed protein γ-glutamyl transpeptidase (GGT) and the ROS-hypobromous acid (HBrO) are potential biomarkers for predicting atherogenesis. Hence, to avoid false-positive diagnoses caused by a single biomarker, we constructed an ingenious sequence-activated double-locked TP fluorescent probe, C-HBrO-GGT, in which two sequential triggers of GGT and HBrO are meticulously designed to ensure that the probe fluoresces in response to HBrO only after GGT hydrolyzes the probe. By utilization of C-HBrO-GGT, the voltage-gated chloride channel (CLC-1)-HBrO-catalase (CAT)-GGT signaling pathway was confirmed in cellular level. Notably, the forthcoming atherosclerotic plaques were successfully predicted before the plaques could be observed via the naked eye or classical immunofluorescent staining. Collectively, this research proposed a powerful tool to indicate the precise position of mature plaques and provide early warning of atherosclerotic plaques.     

Bi靶激光等离子体极紫外光源以及碎屑辐射特性研究

激光等离子体极紫外光源具有体积小、稳定性高和输出波长可调节等优势,在极紫外光刻领域发挥着重要的作用。Bi靶激光等离子体极紫外光源在波长9～17 nm范围内具有较宽的光谱,可应用于制造极紫外光刻机过程中所需的极紫外计量学领域。利用平像场光谱仪和法拉第杯对Bi靶激光等离子体极紫外光源以及离子碎屑辐射特性进行了实验研究。在单脉冲激光打靶条件下,实验中观察到Bi靶激光等离子极紫外光谱在波长12.3 nm处出现了一个明显的凹陷,其对应着Si L-edge的吸收,是Bi元素光谱的固有属性。相应地在波长为11.8和12.5 nm位置处产生了两个宽带的辐射峰。研究了两波长光谱特性以及辐射强度随激光功率密度的变化。结果表明,在改变聚焦光斑大小实现不同激光功率密度（0.7×1010～3.1×1010 W·cm-2）过程中,当功率密度为2.0×1010 W·cm-2时两波长处的光辐射最强,其原因归结为Bi靶极紫外光辐射强度受激光能量用于支撑等离子膨胀的损失和极紫外光被等离子体再吸收之间的平衡制约所致。在改变激光能量实现不同激光功率密度过程中,由于烧蚀材料和产生两波长所需高阶离子随着功率密度的增加而增加,增强了两波长处的光辐射。进一步,研究了双脉冲激光对Bi靶极紫外光谱辐射特性影响,实验发现双脉冲打靶下原来在单脉冲打靶时出现在波长13～14 nm范围内的凹陷消失。最后,对单脉冲激光作用Bi靶产生极紫外光源碎屑角分布进行了测量。结果表明,当探测方向从靶面法线方向移动到沿着靶面方向上的过程中,探测到Bi离子动能依次减小,并且离子动能随激光脉冲能量降低而呈线性减小。此项研究有望为我国在研制极紫外光刻机过程所需的计量学领域提供技术支持和打下夯实的基础。     

高强度聚焦超声（HIFU）——一门多学科的研究课题

高强度聚焦超声(high intensity focused ultrasound, 简称HIFU)已作为一种无创外科工具而应用于门诊治疗肿瘤。文章介绍了它的基本原理、有关的研究现状和存在的问题,以及对今后研究工作的建议。文章特别强调高强度聚焦超声是一门多学科的综合研究课题,需要各方面的科学工作者通力协作。     

Different Hagedorn temperatures for mesons and baryons from experimental mass spectra

We analyze the light-flavor particle mass spectra and show that in the region up to 1.8 GeV the Hagedorn temperature for mesons is significantly larger than for baryons, reflecting the fact that the number of baryon states grows more rapidly with the mass. We show that in dual string models the ratio of the mesonic to baryonic Hagedorn temperatures is equal to .     

Virtual screening of organic molecule databases. Design of focused libraries of potential ligands of NMDA and AMPA receptors

A system of virtual screening of organic molecule databases is designed, which permits preprocessing of databases, molecular docking to a three-dimensional model of receptor, and post-processing of the results obtained. Using this screening system, it is possible to reproduce positions of the known ligands in the glutamate sites of the NMDA and AMPA receptors and in the glycine site of the NMDA receptor, to substantially enrich the database with potentially active compounds, and to distinguish between the agonistic and antagonistic character of the action of these compounds in the case of docking to the open and closed forms of the binding sites. Based on the results of screening of a database of low-molecular-weight organic compounds (total of 135,000 structures) using models of the open and closed forms of the glutamate and glycine sites of the NMDA receptor and of the glutamate site of the AMPA receptor, focused libraries of potential agonists and antagonists of these sites were designed.     

Dual Fiber-In-capillary Annular Column with Ternary Stationary Phase for Gas Chromatographic Separation

In the present work a novel strategy for improving and/or tuning the selectivity of gas chromatographic (GC) separation by combining three different stationary phases (SPs) without premixing was introduced. A fused silica fiber coated with polydimethylsiloxane (SE30) and another coated with cyanopropylphenylmethylpolysiloxane (OV1701) were serially inserted into an 8-m polyethylene glycol 20 M (PEG20M) capillary column to form a GC annular column with ternary SP, abbreviating as SE30-OV1701-CF/PEG20M-CC. The separation capability of this ternary SP annular column was compared with a SE30-coated fiber-in-PEG20M-coated capillary annular column and a PEG20M-coated open tubular column by a test mixture of 19 organic compounds. Among these three columns, SE30-OV1701-CF/PEG20M-CC produced the best separation when the SE30-coated fiber and OV1701-coated fiber was 3 and 5 m, respectively. Selectivity can be easily tuned by changing the length of the SP-coated fibers in the ternary SP annular column. The proposed ternary SP annular column shows additional tunability, thus making it a promising tool for separation of organic solvents that are often used in the manufacturing process of pharmaceutical formulations and lacquer thinners.     

光度法直接测定原生富铂矿及浮选精矿中痕量铂、钯的研究

报道了一个不经预分离富集 ,光度法直接测定原生富铂矿及浮选精矿中的铂、钯的方法。考察了矿样分解方法 ,测定条件的选择 ,大量铁、镍、铜等 2 0余种共存元素的干扰及消除 ,测定方法的精密度和准确度等。在 SG-1 (原生富铂矿 )和 SG98-A(浮选精矿 )样品中 ,测得铂的含量为 5.96± 0 .2 7μg/ g和 2 7.9± 0 .70 μg/ g,钯的含量为 7.71± 0 .2 5μg/ g和 3 9.2± 1 .0 0 μg/ g,结果与铅试金富集法一致。     

用双波长薄层色谱扫描法测定糖脂双降茶中菝契皂甙元的含量

应用双波长薄层色谱扫描法糖脂双降茶中菝契皂甙元的含量,回收率为98.18％,相对标准偏差为2.54％,相关系数为0 9977.该法糖脂双降茶中菝契皂甙元的含量,操作简便、结果稳定、重复性好,可作为质量检验的一个定量方法。     

The novel thermochromic and energy-storage microcapsules with significant extension of color change range to different tones

In order to solve the problem of narrow color change range for common thermochromic material, the novel thermochromic and energy-storage microcapsules (TCEMs) was designed and synthesized by in-situ polymerization. The TCEMs contained optimizational thermochromic components and phase change materials, and exhibited the dual functional performances of thermochromic and energy-storage. Then, the TCEMs were applied to polyester/cotton blend fabric with waterborne polyurethane by coating process. The growing process, exterior morphology, color change effect, temperature-regulable behavior and thermal activity of the TCEMs and the treated fabrics were investigated. The results demonstrated that both TCEMs and modified fabrics had good energy-storage effect and remarkable thermochromic property. Especially, while surrounding temperature changed from 15?°C to 45?°C, the colors of TCEMs and treated fabrics could change from cool-tone (blue) to warm-tone (red), which significantly improved the color change range of the thermochromic material and made the color vary between different tones instead of changing in the region of similar color. The TCEMs exhibited great potentiality in the applying fields of decoration, anti-counterfeiting, architecture and intelligent textile, etc.