Co（1，10－phen·）_3~（2＋）－KIO_4－鲁米诺化学发光体系与应用

本文研究了Ｃｏ（１，１０－ｐｈｅｎ·）３（２＋）配合物对ＫＩＯ４氧化鲁米诺所产生的强化学发光反应．以１，１０－ｐｈｅｎ·为配位体时，Ｃｏ（Ⅱ）的检出限为８×１０（－８）ｇ／Ｌ，工作曲线响应浓度范围在１×１０（－６）～１×１０（－４）ｇ／Ｌ，测定１×１０（－４）ｇ／ＬＣｏ（Ⅱ）离子的相对标准偏差为２．５％．配合物化学发光法检测啤酒、维生素Ｂ（１２）针剂中微量Ｃｏ（Ⅱ）可获得满意结果．     

一种新的共发光体系──铽－钆（钪）－均苯四甲酸体系的研究和应用

本文研究发现铽与均苯四甲酸有强烈的荧光反应，并观察到钆（钪）存在下的共发光现象，研究了该反应的荧光特点和影响因素，确定了反应和测定的最佳条件。钆和钪的引入使原有的铽－均苯四甲酸体系的荧光分别增加了２４０和９５倍。在最佳条件下，对应于钆和钪，铽的浓度分别在５．０×１０－８～３．０×１０－５ｍｏｌ／Ｌ和７．０×１０－８～１．０×１０－５ｍｏｌ／Ｌ的范围内与荧光强度成线性关系，检测限分别为２．０×１０－１０和５．０×１０－１０ｍｏｌ／Ｌ采用多点增量标准加入法测定了合成样品和包头稀土样品中的铽。回收试验的回收率为１００．１±０．０１％和９９．１±０．０３％。     

黄嘌呤氧化酶－乙醛－吖啶酯化学发光分析新体系

乙醛在黄嘌呤氧化酶催化作用下，被空气氧化生成乙酸和过氧化氢，酶反应生成的过氧化氢氧化新吖啶酯试剂［１０－甲基－９－（对甲酰苯基）吖啶羧酸酯氟磺酸盐］产生化学发光，化学发光强度与己醛浓度在一定范围内成线性关系．由此建立了一种化学发光分析新体系，用于测定乙醇含量．线性范围２．０×１０－７～１．２×１０－３ｍｏｌ／Ｌ，测定５．０×１０－７ｍｏｌ／Ｌ乙醛，相对标准偏差为６．８％，检测限为１．２×１０－７ｍｏｌ／Ｌ，测定环境水样中乙醇含量，取得满意结果，回收率为９５～１０６％．     

2—溴甲基萘荧光和室温磷光性质研究

研究了２－溴甲基萘（２－ＢｒＭＮ）的荧光及磷光性质。２－溴甲基萘是一种优良的荧光试剂,λｅｘ／λｅｍ＝２７４／３３４ｎｍ,其浓度在１．０×１０＾－６～１．２×１０＾－４ｍｏｌ·Ｌ＾－１范围内与荧光强度呈良好的线性关系,相关系数ｒ＝０．９９９,最低检测限为４．７×１０＾－８ｍｏｌ·Ｌ＾－１。以β－环糊精（β－ＣＤ）作保护剂和１,２－二溴丙烷（ＤＢＰ）为重原子微扰剂的２－ＢｒＭＮ／β－ＣＤ／ＤＢＰ体系     

双水相体系中Cu(Ⅱ)的显色反应研究

本文研究了铬黑Ｔ（ＥＢＴ）作萃取剂和显色剂,在聚乙二醇－２０００（ＰＥＧ）－Ｎａ２ＳＯ４－ＥＢＴ双水相体系中Ｃｕ（Ⅱ）的显色反应条件及应用,实验结果表明,在ｐＨ８．５缓冲溶液中,将Ｃｕ（Ⅱ）络合物从水溶液中萃取到ＰＥＧ相,其最大吸收波长位于５６０ｎｍ,摩尔吸光系数为３．０５×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,此法用于铝合金中铜的测定,获得了满意结果。     

铂(Ⅳ)-钼酸盐-乙基罗丹明B离子缔合显色反应研究

本文研究了在聚乙烯醇（ＰＶＡ）存在下用钼酸盐与乙基罗丹明Ｂ（ＥＲＢ）形成离子缔合物，该缔合物的最大吸收位于５８０ｎｍ，摩尔吸光系数为１．１２×１０６Ｌ·ｍｏｌ－１·ｃｍ－１，服从比耳定律范围０—２．５μｇ／２５ｍＬ，缔合物至少稳定１周，考察了５０多种共存离子的影响，除生成杂多酸元素和Ａｕ（Ⅲ）、Ｏｓ（Ⅷ）、Ｐｄ（Ⅱ）、Ｉｒ（Ⅳ）外，大多数元素不干扰。测定铂的条件为：〔ＨＣｌＯ４〕＝１．２ｍｏｌ／Ｌ，〔ＭｏＯ４２－〕＝９．１×１０－４ｍｏｌ／Ｌ，〔ＥＲＢ〕＝３．２×１０－５ｍｏｌ／Ｌ，０．０８％ＰＶＡ。缔合物的摩尔比为Ｐｔ（Ⅳ）∶ＥＲＢ＝１∶２，本法已用于铂矿中铂的测定，结果满意。     

吩噻嗪卤代衍生物的荧光研究

本主要研究了３－溴－Ｎ－乙基吩噻嗪（Ｂｒ－Ｐ）在各种酸度、增敏溶剂、感光效应等条件下的荧光变换现象,并确定了最佳的发光体系。方法简单、准确可靠,其线性范围为１×１０＾－７￣１×１０＾－４ｍｏｌ／Ｌ,检出限为１×１０＾－８ｍｏｌ／Ｌ,ＲＳＤ〈２．８％。     

3,4-二羟基苯甲酸的流动注射化学发光抑制分析法

本文基于３,４－二羟基苯甲酸对Ｃｏ２＋离子催化的鲁米诺－Ｈ２Ｏ２化学发光体系的抑制作用,首次建立了３,４－二羟基苯甲酸的流动注射化学发光抑制分析法,发光信号的降低值ΔⅠ与３,４－二羟基苯甲酸的浓度在１×１０－６～１×１０－５ｍｏｌ／Ｌ的范围内呈良好的线性关系,检出限为２．７×１０－７ｍｏｌ／Ｌ（ｎ＝１１）,对８×１０－６ｍｏｌ／Ｌ３,４－二羟基苯甲酸测定的相对标准偏差为２．３％（ｎ＝１１）。     

不除氧条件下环糊精诱导室温磷光法测定喹啉

在不除氧条件下，１０ｍＬ含喹啉／β－ＣＤ溶液中只需加入１５μＬ１，２－二溴丙烷（ＤＢＰ）作重原子微扰剂，就能产生强而稳定的室温磷光信号。最大λｅｘ／λｅｍ＝２７３／４９６ｎｍ。喹啉浓度在５．０×１０＾－７￣５．０×１０＾－５ｍｏｌ／Ｌ，５．０×１０＾－４ｍｏｌ／Ｌ，两段三个数量级范围与室温磷光信号有良好的线性关系，最低检测限７．４×１０＾－８ｍｏｌ／Ｌ。本体系的特点是ＤＢＰ用量少，从而减少了因过量     

稀土元素荧光增强效应的研究─RE对Eu－苯甲酰三氟丙酮－溴化十六烷基三甲基铵体系的荧光增强

本文详细研究了稀土元素Ｌａ３＋、Ｇｄ３＋、Ｔｂ３＋、Ｌｕ３＋、Ｙ３＋及Ｓｃ３＋对铕苯甲酰二氟丙酮（ＢＴＡ）－阳离子表面活性剂体系的荧光增强效应。结果表明，在上述增强离子的分别存在下，体系的荧光强度分别增加１７、７５、６５、５、５５和１８倍，铕浓度在１．０×１０－１０－８．０×１０－７ｍｏｌ／Ｌ范围内与荧光强度成线性关系，最低检出限为１．０×１０－１１ｍｏｌ／Ｌ利用标准加入法测定了混合稀土氧化物中的铕，结果满意。     

Magnetic ordering in HoRu2Si2, HoRh2Si2, TbRh2Si2 and TbIr2Si2 by neutron diffraction

Neutron diffraction study of polycrystalline HoRu₂Si₂, HoRh₂Si₂, TbRh₂Si₂, and TbIr₂Si₂ was performed in the temperature range between 4.2 and 300 K. For HoRu₂Si₂ the magnetic spin alignment of a linear transverse wave mode below the Néel temperature 19 K is observed. This static moment wave is propagating along the b-axis with k=(0, 0.2, 0) and is polarized in the c-axis. The root-mean-square and maximum saturation moments per Ho atom are 9.26 and 13.09μ_B, respectively. HoRh₂Si₂, TbRh₂Si₂ an TbIr₂Si₂ are simple collinear antiferromagnets of +-+- type with Néel temperatures of (27±1), (98±2) and (72±3) K, respectively. For TbRh₂Si₂ and TbIr₂Si₂ magnetic moments are localized on RE ions only and are aligned along the tetragonal axis, while for HoRh₂Si₂ they form an angle ø = (28±3)°.     

13C-selective IRMPD of CBr2F2/Cl2 and CCl2F2/Br2 systems

The CO₂ TEA laser irradiation of CBr₂F₂ in the presence of Cl₂ yielded ¹³C-enriched CBrClF₂ and ¹³C-enriched CCl₂F₂ under selected experimental conditions. As the photolysis proceeded, the ¹³C concentration of CBrClF₂ decreased gradually and that of CCl₂F₂ increased up to 90% or higher. These results can be explained by the mechanism involving the secondary ¹³C-selective IRMPD of the primary product CBrClF₂. On the other hand, the carbon-containing product for a CCl₂F₂/Br₂ system was only CBrClF₂; the further IRMPD of which probably regenerated CBrClF₂ in the presence of Br₂. The decomposition probabilities of ¹²C- and ¹³C-containing molecules in both systems were measured as functions of laser line, laser fluence, and reactant pressures.     

μ+SR study of LaNi2As2, URh2Si2 and CeRh2Si2

Muon spin relaxation experiments have been carried out in the paramagnetic and magnetically ordered states of URh₂Si₂ and CeRh₂Si₂. As the magnetic structure of these compounds is well known, these measurements can help to characterise their magnetic properties probed by μSR and to understand the μSR results of the heavy fermion compounds of the same crystallographic family. Our measurements show that the muons occupy two different crystallographic sites. The spectra of URh₂Si₂ and CeRh₂Si₂ in the magnetically ordered states are very different, probably reflecting their different magnetic structures. The spectra obtained on CeRh₂Si₂ are similar to the published spectra of the heavy fermion compound CeCu_2.1 Si₂. Muon spin rotation measurements on LaNi₂As₂ indicate that the muon is diffusing at 150 K.     

Eu2+掺杂CaSi2O2N2荧光粉发光性能

采用固相反应法合成了组成为Ca_1-xEu_xSi₂O₂N₂的Eu²⁺掺杂CaSi₂O₂N₂荧光粉.通过荧光光谱对样品的发光性能进行了研究,发现Eu²⁺掺杂CaSi₂O₂N₂荧光粉发射光谱为宽波段的单峰结构,主要包含绿光和黄光区,发射峰在556~568 nm.从发射光谱的宽带特征来看,CaSi₂O₂N₂:Eu²⁺的发射主要对应着Eu²⁺离子4f⁶5d→4f⁷跃迁.从激发光谱所覆盖的范围还可以看到,样品可以有效的被UV蓝-光激发,这意味着该类荧光粉在白光LED方面有可能得到广泛的应用.另外,样品的发光性能与激发离子的浓度有着很大关系.激发离子浓度增大时,发射光谱会发生明显红移.利用这一性质,可以通过改变Eu²⁺浓度来调节荧光粉的发光范围,从而满足不同场合的需要.同时,Eu²⁺浓度提高,样品发射光谱的强度也会随之增强,在x=0.06时发射强度达到最大值,之后继续增加Eu²⁺浓度,强度不仅没有增加反而降低,即出现浓度猝灭现象.     

Superconductivity in LaPd_2Bi_2 with CaBe_2Ge_2-type structure

正Since the discovery of superconductivity in LaFeAsO_(1-x)F_x,the high-T_c iron-based superconductors have been extensively studied from both experimental and theoretical viewpoints [1-8]. However, the mechanism of the unconventional superconductivity is still to be resolved. To     

Polar optic phonons in Hg2Cl2 and Hg2Br2

Far infrared (30–430 cm^?1) reflectivity measurements of Hg₂Cl₂ and Hg₂Br₂ single crystals have been performed in polarized light. The spectra, which are in agreement with group-theoretical predictions, were analyzed by the oscillator fitting procedure and Kramers-Kronig method. The results are compared with the existing data from other measurements and the large anisotropy of polar modes is briefly discussed. The polarization vectors of all long-wavelength symmetry modes were determined group-theoretically.     

Magnetostriction of SmMn2Ge2 and GdMn2Ge2 intermetallic compounds

Longitudinal and transverse magnetostrictions of polycrystalline samples of intermetallic compounds RMn₂Ge₂ (R=Sm or Gd) are measured in pulsed magnetic fields up to 250 kOe. It is found that linear magnetostrictive strains of about 10^?3 arise in a temperature range in which the magnetic field causes a change in the magnetic state of a manganese magnetic subsystem. The results obtained are described within the model of a two-sublattice ferrimagnet with a negative exchange interaction in the manganese subsystem in terms of a strong dependence of this interaction on interatomic distances.     

X-ray photoemission spectra measurements of CeNi2Sb2 and CeCu2Sb2

X-ray photoemission spectra, resistivity and susceptibility of CeNi₂Sb₂ and CeCu₂Sb₂ were measured and are discussed. The results indicate that these alloys are Kondo systems. For comparison of the valence band properties, the spectra of the isostructural alloys of RT₂X₂-type with R = La, Gd, T = Cu, Ni and X = Sn, Sb were investigated, too.