模糊聚类-偏最小二乘光度法同时测定锇和钌

将模糊聚类分析与偏最小二乘相结合，对锇、钌双组份重叠光谱进行解析；较好地解决了校正分析中校准模型的优化问题，提高了分析结果的准确度；研究了锇、钌－ＳｎＣｌ２－乳化剂ＯＰ－阿拉伯树胶（ＡＧ）－丁基罗丹明Ｂ（ＢＲＢ）高灵敏多元离子缔合物显色体系。锇、钌的检出限分别为 ０，６３２ μｇ／Ｌ和 ０．３６８ μｇ／Ｌ，模拟地质样品分析结果的相对误差小于±１０％。     

用罗丹明B和钼酸铵水相光度法测定痕量锇

本研究在聚乙烯醇存在下，锇与钼酸铵形成络阴离子，继而与罗丹明Ｂ（ＲＢ）形成离子缔合物，该缔合物的摩尔吸光系数ε值为２．６２×１０＾６Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，性范围０－１．２μｇ／２５ｍＬ，检测限为１．３ｎｇ／ｍＬ（ｎ＝８），ＲＳＤ为２．２％（ｎ＝７），缔合物稳定４周，考察了３０多种共存离子的影响，除贵金属和能形成杂多酸的元素外，大多数贱金属不干扰。方法已用于测定某些催化剂和岩矿中的锇，结果     

催化动力学光度法测定痕量锇——中性红—氯酸钾—锇（Ⅷ）—砷（Ⅲ）体系

催化动力学光度法测定痕量锇—中性红－氯酸钾－锇（Ⅷ）－砷（Ⅲ）体系唐宁莉傅明来（桂林工学院应用化学系，桂林，５４１００４）利用锇对溴酸钾氧化中性红而建立的催化光度法测定锇，选择性较好，但需控制反应温度为３０℃，操作较严格，应用受到限制．我们用氯酸钾...     

高碘酸盐氧化亚甲蓝动力学光度法测定痕量锇

以Ｏｓ（Ⅳ）催化高碘酸盐氧化亚甲蓝（ＭＢ）反应为基础提出了测定痕量锇的方法。在９０℃加热１４ｍｉｎ和６６０ｎｍ波长处采用固定时间法测定亚甲蓝吸收的降低,锇浓度在０～３．２μｇ／Ｌ范围呈线性关系,检了限为０．０２μｇ／Ｌ,对１．６μｇ／Ｌ Ｏｓ（Ⅳ）测定的ＲＳＤ为１．５６％（ｎ＝１１）,催化反应对Ｏｓ（Ⅳ）、ＭＢ、ＫＩＯ４和Ｈ２ＳＯ４均为一级反应,催化反应的表观活化能为８７．７２ＫＪ／ｍｏｌ,探讨了     

乙基罗丹明B-高碘酸盐催化光度法测定锇

在０．００８ｍｏｌ／Ｌ硫酸介质和热水浴中,Ｏｓ（Ⅳ）催化高碘酸盐氧化乙基罗丹明Ｂ（ＥＲＢ）褪色,建立了灵敏催化光度法测定锇,Ｏｓ（Ⅳ）浓度在０￣８．８ｎｇ／ｍＬ范围成线性关系,检出限为０．０２６ｎｇ／ｍＬ,对６．０ｎｇ／ｍＬ Ｏｓ（Ⅳ）测定的相对标准偏差为１．８８％（ｎ＝１１）,催化反应对Ｏｓ（Ⅳ）、ＥＲＢ、ＫＩＯ和Ｈ２ＳＯ４分别为一级反应,表观活化能为２０５．７ｋＪ／ｍｏｌ。探讨了反应机理,研究     

模糊聚类—偏最小二乘光度法同时测定锇钌

将模糊聚类分析与偏最小二乘相结合，对锇，钌双组份重叠光谱进行解析；较好地解决了校正分析中校准模型的优化问题，提高了分析结果的准确度；研究了锇，钌－ＳｎＣｌ２－乳化剂Ｏ－阿拉伯树胶－丁基罗丹明Ｂ高灵敏多元离子缔合物显色体系。锇，钌的检出限分别为０．６３２μｇ／Ｌ和０．３６８μｇ／Ｌ，模拟地质样品分析结果的相对误差小于±１０％。     

偶氮氯膦-mA-锇-高碘酸钾催化光度法测定微量锇

在碱性介质中,锇（Ⅳ）对KIO4氧化偶氮氯膦－mA的褪色反应有明显的催化作用,据此建立了催化光度法测定微量锇（Ⅳ）的新方法,并用正交实验设计对反应条件进行了优化。方法的检测限为2．0μg/L。锇（Ⅳ）含量在7．0－25．0μg/L范围内服从比尔定律。此方法已用于贵金属精矿和二次合金中微量锇的测定,相对误差均为0．9％,回收率在95．38％－106．0％之间。     

水杨基荧光酮—过氧化氢催化动力学光度法测定痕量锇（Ⅳ）

在碱性介质中，痕量锇（Ⅳ）对水杨基荧光酮（ＳＡＦ）与过氧化氢的氧化还原反应有显著的催化作用。本文以此为基础，提出用分光光度催化动力学测定痕量锇（Ⅳ）的新方法。本法未加掩蔽剂时的线性范围是０．０８－０．８０μｇ／Ｌ，加入掩蔽剂后的线性范围是０．０８－０．８０μｇ／Ｌ，检出限为０．０８μｇ／Ｌ。本法用于实际样品中Ｏｓ（Ⅳ）的测定，结果良好，本实验还测定了此催伦反应的活化能和反应级数。     

双波长分光光度法同时测定贵金属钯和锇

本文提出了在对羟基苯基荧光酮和溴化十六烷基三甲烷基甲胺存在下，双波长分光光度法同时测定微量和锇的新方法，在ｐＨ＝７．６～８．０的磷酸盐介质中，钯和锇的对羟基苯基荧光酮－ＣＴＭＡＢ配合物吸收光谱相互重叠，选择测定钯配合物的波长对为５８０．５ｎｍ与５３０．５ｎｍ，测定锇配合物的波长对为５５３．５ｎｍ与６０４．５ｎｍ，钯含量在０～７．０μｇ／１０ｍＬ范围内，锇含量在０～９．０μｇ／ｍＬ范围内，与ΔＡ值呈     

联氨在d—过渡金属配合物的MTP（о—NO2）TBP修饰石墨电…

研究了Ｎ２Ｈ４在间－四（邻－硝基苯基）四苯并卟啉铁（Ⅲ）、钴（Ⅱ）、锌（Ⅱ）和镍（Ⅱ）配合物［ＭＴＰ（о－ＮＯ２）ＴＢＰ，简称ＭＴＢＰ］修饰石墨电极上的催化电氧化反应，测得该系列金属四苯并卟啉的催化活性的顺序为Ｃｏ（Ⅱ）ＴＢＰ＞ＣｌＦｅ（Ⅲ）ＴＢＰ＞Ｎｉ（Ⅱ）ＴＢＰ＞Ｚｎ（Ⅱ）ＴＢＰ≈石墨，考察了Ｃｏ（Ⅱ）ＴＢＰ和ＣｌＦｅ（Ⅲ）ＴＢＰ催化联氨电氧化反应的动力学过程。结果表明，ＯＨ＾－和Ｎ２Ｈ４在Ｃ     

SPECTRAL CHARACTERISTICS OF THE EXCITED STATES OF THE PRODUCT OF THE CHEMILUMINESCENCE OF LUMINOL*

Abstract— In dimethylsulfoxide the emission spectrum of luminol chemiluminescence is red-shifted by 300 cm^-1 from the photoexcited fluorescence of the product 3-aminophthalate dianion, while in aqueous solvent the two spectra are identical. The spectral properties of the product dianion have been measured in aqueous solvent and in a number of aprotic solvents, both at room temperature and at 77°K. The ground states and the excited states from which emissions are observed are characterized. Two alternatives are presented to explain the aprotic emission spectra.     

光谱透射比标准物质的研究

研制了紫外、可见、近红外光谱区通用光谱透射比较标准物质。以高纯熔融石英为基片材料，镍铬合金的镀膜材料，采用双光楔对称光胶结构以消除同色杂散光的影响，对镀膜进行光胶处理以保证膜层的强度、稳定性及光学中性，采用高精度分光光度测量装置作为定值手段的以保证准确的定值，设计定位保护架以消除多次反射误差。该光度标准适用的光谱范围的200-2600nm，光谱透射比定值不确定度为0.5%。     

丙烯聚合络合催化剂形成过程的研究

以倍半物为还原剂还原TiCl_4,经异戊醚络合处理,然后在TiCl_4己烷溶液中35℃条件下热处理,制得对丙烯聚合具有高活性和高定向度的络合催化剂。研究了制备过程中各步反应产物的组成和结构特征,并讨论了TiCl_3低温晶型转变机理。     

ON THE ACCURACY OF DIFFERENTIAL MEASUREMENTS OF THE MINIMAL ERYTHEMA DOSE: INFLUENCE OF THE DISCRETENESS OF THE SCALE

The minimal erythema dose (MED) is often used as a quantity by which the influence of certain treatments of the skin can be measured. Differential measurements are performed by assessing the difference of the MED on the skin treated in some way and the untreated skin.
As the MED-measuring scale is discrete, the question is sometimes raised whether it is possible to measure differences smaller than one scale unit. In the present paper it is shown that this is indeed possible; in principle the discreteness of the scale does not impose any restriction on the smallest value of the difference that can be measured. The discreteness of the scale introduces an extra random variation into the measurement. This variation is estimated theoretically. It is automatically included in the usual error analysis.
The discreteness variance is small when compared to other variance components, which are computed from an analysis of variance of actual experiments. Reducing the discreteness variance, by reducing the dose decrement of the MED-measuring scale, therefore, does not enhance the overall accuracy considerably. Finally, it is found that the assessments of the MED by the various observers do not differ significantly from each other, and that multiple assessments do increase the accuracy, especially for small effects.     

对苯二胺衍生物的光催化氧化

以ＴｉＯ２作为催化剂，利用波长＞３３０ｎｍ的光辐照研究了Ｎ－取代的对苯－二胺衍生物的光催化氧化。研究表明，氧分子与光生电子 反应生成羟基自由基，羟基自由基氧化ＰＰＤｓ，生成醌二亚胺，后者在羟基的进攻下脱氨生成苯醌，苯醌继续光解无机化。ＰＰＤｓ光催化氧化近似遵循一级反应动力学，醇类和硫酸根离子可抑制ＰＰＤｓ的光催化氧化。催化剂表面荷影响电子转移速率，从而控制光催化氧化的反应速率。     

分光光度法低浓度区不成线性关系的探讨

本文研究分光光度法低浓度区不成线性的有关因素及其克服方法,以铝-二甲酚橙体系为例,通过对体系不同条件下吸收光谱及其等色点的研究,发现当体系pH渐变时(铝,二甲酚橙浓度固定不变),曲线簇现两个等色点.从对等色点的分析,证明体系形成络合物须按一个反应式进行才能出现等色点,而与反应式是否涉及到两个或三个有色化合物无关.若同时按两个反应式进行,则不能得到等色点,测定时也无线性关系.所以用这个体系进行铝的测定,铝浓度的变化范围只能限于存在等色点的区间才有线性关系. 为了克服常法测定铝时不符线性的现象,本文采用的方法是在二甲酚橙中预先加适量的铝作为显色剂,使反应严格按一个反应式进行,所得结果为一直线.     

六氟丙烯等离子体聚合机理研究

<正> 在以前的工作中,我们曾应用色谱-质谱(GC-MS)及顺磁共振(ESR)等方法研究了四氟乙烯和三氟氯乙烯等离子体聚合过程中气体冷凝物的组成及结构,提出自由基引发聚合反应机理。本文用类似方法研究六氟丙烯(HFP)等离子体气体冷凝物的组成与结构和冷凝物的ESR信号及其从低温到高温的变化规律,证实了自由基的稳定性并提出气相聚合反应机理。     

THE COMPLEXITY OF THE FLUORESCENCE OF CHLORELLA PYRENOIDOSA

Abstract— The complexity of the room-temperature emission spectrum of Chlorella was investigated by a matrix analysis method. This approach revealed the presence of two independently fluorescent components in the short-wave region of the spectrum. These components, maximal at about 687 and 695 nm, appeared to correspond to the fluorescence of the bulk pigments of PS II and PS I respectively. The analysis was insensitive to the individual species within the photosystems. As such, other minor fluorescent species, usually observed at low temperatures, which presumably correspond to fluorescence from the trapping centres, did not appreciably complicate the analysis. The absorption spectra of the two photosystems were calculated from the fluorescence data. The results were similar to those that have been obtained by other workers from oxygen evolution and DCMU poisoning data but differed from those obtained by computer analysis of the absorption spectrum. Addition of reduced DCPIP was observed to reverse the increase in fluorescence yield and changes in the spectral distribution of emission taking place on poisoning the algae. The correlation between this and the catalysis of photophos-phorylation in aged or poisoned chloroplasts was noted. This correlation was tentatively interpreted as evidence for a direct interaction between the donor system and the photochemical apparatus associated with PS II, rather than with a member of the electron transport chain as is normally assumed.     

纳米SiO2锚固光敏基团引发MMA光接枝聚合研究

对纳米SiO2进行了锚固光引发剂的表面修饰,进而引发甲基丙烯酸甲脂(MMA)光接枝聚合制备有机/无机复合粒子.纳米SiO2粒子首先用氯化亚砜进行表面氯化,再与光引发剂2-羟基-4-(2-羟基乙氧基)-2-甲基苯丙酮(Irgacure2959)反应从而锚固上光引发剂.通过紫外光引发MMA在经过修饰过的纳米SiO2表面上进行表面光接枝聚合.采用IR、TGA和TEM等方法表征了接枝前后纳米粒子的变化,证明了表面接枝物的存在,并研究了不同反应条件对单体转化率、接枝率和接枝效率的影响.研究结果表明,搅拌对接枝过程的影响比较显著.TGA结果显示未搅拌聚合时接枝率只能达到比较小的程度,而在搅拌条件下180min内MMA的接枝率可达到110%.