A chelating resin containing S, N and O atoms: Synthesis and adsorption properties for Hg(II)

A novel chelating resin containing S, N and O atoms (PSME-EDA) was synthesized by using poly(2-hydroxyethylmercaptomethylstyrene) (PSME) and diethanolamine (EDA) as materials. Its structure was characterized by elemental analysis, Fourier transform-infrared spectra (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The adsorption of the resin for Hg²⁺ was investigated. The saturated adsorption capacity of PSME-EDA for Hg²⁺ could reach to about 1.1 mmol/g at 25 °C when the initial Hg²⁺ concentration was 0.02 mol/l. Some factors affecting the adsorption such as temperature, reaction time and ion concentration were also studied. The results showed that adsorption was controlled by liquid film diffusion. The increasing of temperature was beneficial to adsorption. The Langmuir model was better than the Freundlich model to describe the isothermal process. The values of ΔG, ΔH, and ΔS calculated at 25 °C were −7.99 kJ mol⁻¹, 22.5 kJ mol⁻¹ and 34.4 J mol⁻¹ K⁻¹, respectively. The adsorption mechanism of PSME-EDA resin for Hg(II) was confirmed by X-ray photoelectron spectroscopy (XPS).     

Packing capilllary electrochromatography columns using vacuum--a preliminary study

This paper introducesa novel method for packing Capillary Electrochromatography Columns (CEC). Using vacuum packing methodology, silica particles as small as 1 microm were successfully packed into the capillary columns with 75 microm inner diameter. The columns are verystable and show no noticeable loss in efficiency after 200 sample injections. The performance of these vacuum packed capillary columns was evaluated with a mixture of aromatic and non-aromatic compounds. A 24 cm long capillary column can produce peak efficiencies of around 45,000 plates for benzene.     

Electrochemical studies of NiTMpyP and interaction with DNA

In this paper, cyclic voltammetry, linear sweep voltammetry and chronocoulometry in connection with the hang mercury drop electrode were used to study NiTMpyP and its mixture with DNA. The reduction of NiTMpyP in our experimental conditions involves in 4e reduction of TMpyP. NiTMpyP interacting with DNA forms electrochemically non-active complex DNA-2NiTMpyP, which can not be reduced on the Hg electrode. The peak potential of NiTMpyP does not shift and its electrochemical kinetic parameters indicate no significant change in the presence of DNA. However, the reduction current of NiTMpyP decreases obviously due to the formation of DNA-2NiTMpyP, which implies its equilibrium concentration decreases when DNA was mixed. The decrease of peak current is proportional to DNA concentration, which can be applied to estimate DNA concentration.     

Thermochemistry of rare earth complexes [Ln(Ala)2(Im)(H2O)](ClO4)3 (Ln=Pr, Gd)

The two complexes, [Ln(Ala)₂(Im)(H₂O)](ClO₄)₃ (Ln=Pr, Gd), were synthesized and characterized. Using a solution-reaction isoperibol calorimeter, standard enthalpies of reaction of two reactions: LnCl₃⋅6H₂O(s)+2Ala(s)+Im(s)+3NaClO₄(s)=[Ln(Ala)₂(Im)(H₂O)](ClO₄)₃(s)+3NaCl(s)+5H₂O(l) (Ln=Pr, Gd), at T=298.15 K, were determined to be (39.26±0.10) and (5.33±0.12) kJ mol^–1 , respectively. Standard enthalpies of formation of the two complexes at T=298.15 K, Δ_fH^Θ_m {[Ln(Ala)₂(Im)(H₂O)](ClO₄)₃(s)} (Ln=Pr, Gd), were calculated as –(2424.2±3.3) and –(2443.4±3.3) kJ mol^–1 , respectively.     

四苯硼酸盐的热化学研究——Ⅱ.一价四苯硼酸盐的标准生成焓

本文用自行建立的精密溶解层热装(?)测定了298.15K时,NH_4BPh_4、KBPH_4、RbBPh_4、CsBPh_4、TlBPh_4、AgBPh_4和HgPh_2七种沉淀反应的反应焓,由此计算了一价四苯硼酸盐的标准生成焓、熵及吉布斯自由能.     

铁电体爆-电换能的实验研究

使用掺铌PZT97.5/2.5铁电陶瓷样品在垂直工作模式下,进行了爆-电换能的实验研究。在电感-电容并联负载上获得了1360安的峰值电流;在电阻负载上获得了145×10³伏的峰值电压。实验结果与理论预计符合得比较好。 关键词：     

细胞呼吸爆发的微量量热学研究

The heat production of Wistar rat polymorphonuclear leukocytes (PMN) was measured by an LKB 2277 Thermal Activity Monitor. When PMN were activited with phorbol-12-myristate13-acetate (PMA), the respiratory burst was recorded by greatly incr eased heat production. Experiment was also carred out in the present of the inhibitor, Total Flavonoids of Lycium Barbarum L. (TFL). The respiratory burst heat production peak was disappeared, but the heat production curve was higher than that of PMA because TFL increased the metabolic activities of PMN.     

Synthesis and modification of terrylenediimides as high-performance fluorescent dyes

Two new synthetic approaches to terrylenediimides, highly photostable fluorescent dyes, are described. For the first time terrylenediimide has been synthesised in a straightforward procedure that makes large quantities available. The second route includes an efficient cross-coupling reaction followed by a cyclodehydrogenation. Monofunctionalisation of the imide structure allows terrylenediimides now to be coupled with a variety of compounds, for example, by Suzuki cross-coupling, which can lead to an array of terrylenediimides with new functional groups such as hydroxy, amino, or carboxy groups needed to link up with other molecules. The functionalisation in the bay region is used to tune the properties of terrylenediimides and extend the range of applications, for example, by introducing water solubility. These tetrasubstituted terrylenediimides offer, depending on the substituents used, exciting features such as good solubility in common organic solvents, water solubility, or NIR absorption.     

流动注射分析光度法同时测定镍和铁

建立了流动注射（ＦＩＡ）光度法同时测定镍和铁的新方法，以乙酸－乙酸钠缓冲溶液（ＰＨ４．５０）作载液，溴化十六烷基三甲胺作增溶剂，记录５６０ｎｍ处Ｎｉ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ与Ｆｅ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ的峰值吸收之和７４６ｎｍ处Ｆｅ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ的吸不度测定了钠基合金中的镍和铁。两咱离子的定量线性范围分别为０．１０－１．２０ｍｇ／ｌＬ和０．２０－１．６０ｍｇ／Ｌ，检出限为０．０２ｍｇ／Ｌ     

水杨酸与二烷基亚磷酸酯反应历程31P NMR与电喷雾质谱跟踪研究

The reaction between salicylic acid and dialkyl phosphite was traced by electrospray ionization mass spectrometry and ^31P NMR. All reactants, unstable intermediates and products were detected. The mechanism was proposed based on ESI-MS results and ^31P NMR profiles.