稀土离子间反斯托克斯能量传递计算的改进 2.数值模拟计算和分析

对稀土离子能级的动力学过程进行了数值计算,并对各个能级的布居概率改变进行了分析。发现如果不考虑斯托克斯过程和反斯托克斯过程之间的区别而采用原有声子辅助能量传递理论中相同的计算公式对待两种过程的话,得到的理论计算结果就与我们实验得到的校准的结果不一致,为了能够准确描述反斯托克斯能量传递过程,众所周知的量子喇曼理论相对于经典拉曼理论在斯托克斯与反斯托克斯过程的强度比上所增加的比值系数exp{ΔE/kT}被首次成功地引入来描述反斯托克斯能量传递。在能量传递计算理论中引入该比值系数之后,理论计算结果与实验结果符合的非常好,并且发现该比值系数在对纳米尺度材料的光子学研究探索中会发挥至关重要的作用。     

Fluorescence enhancement and cytotoxicity reduction of bis-viologen biphenyl by complexation of cucurbit[7]uril

The effect of cucurbit[7]uril(CB[7]) on fluorescence properties and biocompatibility of the bis-viologen biphenyl molecule(BPV2~(2+)) was investigated by using ~1 H NMR spectroscopy,fluorescence emission titration,and in vitro cytotoxicity experiments.CB[7] can be combined with BPV2~(2+) in a stoichiometric ratio of 1:1 and 2:1.After the formation of host-guest complex,the fluorescence emission intensity of BPV2~(2+) increased significantly,and the emission spectrum blue shifted.Meanwhile,the host-guest complexes showed better biocompatibility than BPV2~(2+) in cell cytotoxicity studies.Results of this paper lay a foundation for the development of host-guest type of fluo rescent probes,biological imaging and so forth.     

中国水协总磷测定方法改进探讨

对中国城镇供水协会推荐的水中总磷测定方法进行了改进，重现性、回收率及质控样品测定结果均符合微量分析要求。     

New pallet irradiation for Gammaster International

State of the art technology offers many opportunities to improve production process with ionizing radiation. Also the requirements to this process become more and more stringent; who was aware of the ISO-9000 Standards? Now it is a necessary concept?Internal and external audits, in particular by Regulatory Bodies such as the FDA and DHSS/MCA, are necessary and commonplace requirements when operating in the Healthcare and Pharmaceutical sectors.Efficiency is a major requirement for industry and also for our radiation business.With all the above mentioned items in mind, Gammaster International B.V. in close cooperation with Nordion International Inc. has developed and built a new type Pallet Irradiator.In this new concept, our 22 years experience in gamma processing and the expertise gained in 10 years of operation of pallet irradiators was incorporated.For this irradiator Gammaster International designed and built a new process control console, incorporating state of the art technology such as:

• - A well-balanced safety system

• - A control panel, with status indication for all essential operating and safety parameters

• - Advances warning for necessary maintenance work

• - Automatic timer-setting control in addition to an automatic timer setting modification

• - Clear indication of the position of the product inside the unit and its status

• - Fully automatic product information generated when the product leaves the irradiation unit

• - Visual process control with the help of a color monitor

• - Incremental dose-control

• - Fault identification

草酸亚铁制备及组分测定综合实验之更新探索

在实验教学中,增加综合性实验内容,开设研究性、探索性和创新性综合实验是化学专业人才培养的重要组成部分。改革更新"草酸亚铁制备及组成测定"的实验方法,并以此创新综合实验为例,引导学生综合运用所学理论知识设计并优选实验方案。通过综合实验的训练,加深学生对实验及科研方法的理解,提高其实验技能及合作交流的能力。     

ICP-MS测定淀粉铝含量的不确定度评定及改进方法

测量不确定度,表征合理地赋予被测量之值的分散性。应用ISO/IEC Guide 98: 1993 Guide to the expression of uncertainty in measurement(简称GUM方法)的自下而上的策略进行测量不确定度的评定,剖析完整的分析测量过程,可以找出影响测量结果准确性的主要因素;采取针对性的措施,设法消除或降低这些因素的影响,可以改进测量方法。以电感耦合等离子体质谱法测定淀粉和面包糠中铝含量为例,其不确定度来源于测量重复性、最小二乘法拟合工作曲线的过程、标准储备液及其分取稀释过程的不确定度、溶液体积及样品称量过程的不确定度。经过各不确定度分量的评定,得知主要分量是由最小二乘法拟合工作曲线引入的相对标准不确定度u_rel(c_Al)₁,其次是由配制标准溶液系列的稀释过程引入的相对标准不确定度u_rel(c_Al)₃、由测量结果的重复性引入的相对标准不确定度u_rel(rep)。因此,采取较高灵敏度的质谱工作模式、增加测定次数、合理选取校准曲线的系列浓度点数值、选用相对误差较小的量器等措施进行方法改进。改进之后,三个主要分量u_rel(c_Al)₁,u_rel(c_Al)₃,u_rel(rep)分别从(0.035 8,0.013 2,0.008 5)降为(0.006 0,0.010 5和0.003 3),铝量的合成相对标准不确定度从0.039降为0.013,扩展不确定度从1.8 mg·kg-1降为0.4 mg·kg-1(k=2),效果显著。