甘氨酸锌螯合物的合成与结构表征

以甘氨酸和碱式碳酸锌为原料合成了甘氨酸锌螯合物 ,最佳工艺条件为 :n (甘氨酸 )∶n(碱式碳酸锌 ) =1 0 0∶0 35 ,温度 95℃ ,反应时间 8h ,产率≥ 92 %。用元素分析、红外光谱、热重差热分析、X射线粉末衍射对螯合物进行了表征 ,其组成为 [Zn(NH2 CH2 COO) 2 ]·H2 O。X射线粉末衍射数据指标化结果表明所合成的螯合物属于单斜晶系 ,晶胞参数为 :a =0 76 42nm ,b =1 182 7nm ,c =1 6 46 5nm ,β=81 75° ,V =1 472 7nm3 。     

活化硅酸特性与生产性应用研究

pH越接近中性,硅酸的胶凝速度越快,碱度或酸度越高,胶凝速度相对减缓;硅酸活化过程中单体和低聚体迅速转化为高聚体,活化产物中氧化硅的主要存在形态为高聚体,达80%以上,凝胶色谱测定其相对分子质量为9.3×103,制备的活化硅酸为粒状阴离子型无机高分子物质。黄浦江原水中活化硅酸助凝剂最佳投加质量浓度约1mg/L(以SiO2计),可以节省混凝剂用量28.2%,沉淀池出水浊度稳定。     

高效液相色谱法测定从酚焦油裂解液中回收的苯乙酮含量

报道了高效液相色谱法测定苯酚焦油裂解液中苯乙酮的含量。采用SpherisorbC18色谱柱(2 5 0mm× 4 .6mm ,5 μm) ,乙腈 /水 /醋酸 (体积比 6 0 :39:1)为流动相 ,流速 1.0mL·min-1,检测波长 2 4 5nm。结果表明 :苯乙酮在 0 .5～ 10 2× 10 -3 g·L-1浓度范围内线性关系良好 (r =0 .9998) ,RSD不大于 1.1%。该法操作简单、快速、准确 ,适合于苯酚焦油中回收苯乙酮的生产过程分析和成品质量检验。     

《室内装饰装修材料 胶粘剂中有害物质限量》国家标准简介(下)

3 .3　胶粘剂中甲苯、二甲苯含量的测定3.3.1　测定方法试样用适当的溶剂稀释后 ,直接用微量注射器将稀释后的试样溶液注入进样装置 ,并被载气带入色谱柱 ,在色谱柱内被分离成相应的组分 ,用氢火焰离子化检测器检测并记录色谱图 ,用外标法计算试样溶液中甲苯和二甲苯的含量。3.3.2　测定条件1 .汽化室温度 :2 0 0℃ ;2 .检测室温度 :2 5 0℃ ;3.检测器 :氢火焰离子化检测器 ;4.色谱柱 :毛细管柱 (ＤＢ 1 :固定液为二甲基聚硅氧烷 ,30ｍ× 0 .5 3ｍｍ× 1 .5 μｍ) ;5 .载气 :氮气 ,纯度大于 99.9% ,其柱前压为 70ｋＰａ( 35℃ ) ;6.程序升温…     

RP-HPLC法测定朝鲜蓟中绿原酸的含量

建立了朝鲜蓟中绿原酸测定的高效液相色谱法。采用DiamandC_(18)色谱柱(200×4.6mm 5μn)(迪马公司色谱专家),以乙腈-水-甲酸(体积比23∶230∶1.2)淋洗,用紫外检测器于328nm处测定,各组分的色谱峰达到基线分离。绿原酸在7.2～360 ng/mL 范围内线性关系良好,线性方程为Y=6.379×10~(-4)-0.597,线性相关系数r=0.9999;平均回收率为102.37%;RSD=1.422%(n=7)。并对朝鲜蓟不同部位的绿原酸含量进行了测定,结果满意。     

核黄素的循环伏安法分析

介绍了在 NH3 · H2 O- NH4 Cl( PH=1 0 )缓冲溶液中的核黄素 (维生素 B2 )循环伏安图 ;核黄素在 - 0 .545V( VS.Ag Cl/Ag)产生一个阴极峰 ;在 - 0 .50 6 V产生一个阳极峰。其波高与核黄素溶液的浓度分别在 6× 1 0 - 7～ 7× 1 0 - 6mol· l- 1和 4× 1 0 - 7～ 8× 1 0 - 6mol· l- 1范围内成线性关系 ,检测限分别为 4× 1 0 - 7mol· l- 1和 2× 1 0 - 7mol· l- 1。     

测定柠檬黄的电位型漆酚树脂化学传感器研究

:报导了以湖北长阳县出产的山漆为原料合成漆酚树脂 ,以此漆酚树脂为载体 ,研制了测定合成食用色素柠檬黄的电位型化学传感器。此传感器对柠檬黄浓度在8.0× 1 0 -7～ 1 .0× 1 0 -3 mol/L间的响应符合 Nernst关系式 ,斜率为 2 1 .0 m V( 30°C,p H6.0 ) ,检测下限为 3.0× 1 0 -7mol/L。传感器的选择性、重现性和稳定性良好 ,对样品的测定结果与食用色素通用测试方法 ( OT- 1 5)基本一致。     

阴离子交换色谱法分离含钴溶液中锌、镉、铜等杂质

采用阴离子交换色谱法,研究了某锌厂冶炼废渣的硫酸化焙砂浸出液中钴与锌、镉、铜等杂质离子的分离工艺,确定了最佳工艺参数：将料液配制成含2 mol/L Cl–1和0.1 mol/L Na2SO3的溶液,调节pH值为 4.5,搅拌数分钟,料液pH值降低至 4.0后,用201?7阴离子交换色谱柱进行分离,柱后流出液中锌、镉、铜等杂质的含量达到钴冶金工艺要求,钴的损失为0.7%左右.     

柱前衍生HPLC法测定人凝血因子Ⅷ中氨基酸的含量

目的建立人凝血因子Ⅷ中氨基酸含量的柱前衍生HPLC检测方法。方法采用6-氨基喹啉基-N-羟基琥珀酰亚氨基氨基甲酸酯(6-aminoquinoline-N-hydroxysuccinimide carbamate,AQC)在一定条件下与氨基酸形成稳定的衍生产物(柱前衍生),再通过高效液相色谱仪,采用氨基酸分析柱(150 mm×3. 9 mm,4μm)检测,以不同流动相进行梯度洗脱[在《中国药典》三部(2015版)的基础上进行调整],柱温为37℃,流速为1. 0 mL/min,检测波长为248 nm。同时验证方法的系统适应性、专属性、线性范围、精密性及准确度。结果甘氨酸及盐酸赖氨酸均可在25 min内获得较好分离,与相应相邻色谱峰之间的分离度均 1. 5,拖尾因子在0. 95～1. 40之间;各样品的氨基酸种类均能正确检出,混合样品与单纯样品出峰时间保持一致,且供试品溶液与对照品溶液主峰保留时间相对偏差均2%;当甘氨酸浓度在12. 5～62. 5μg/mL,盐酸赖氨酸浓度在4. 0～20. 0μg/mL时,与相应氨基酸与内标峰面积比呈良好的线性关系,相关系数(r)分别为0. 999 9和0. 999 8;甘氨酸及盐酸赖氨酸重复性的相对标准偏差(RSD)分别为0. 4%和0. 5%,中间精密度RSD分别为1. 3%和1. 0%;两种氨基酸的回收率均在95%～105%范围内,RSD均≤2%。结论建立的方法具有良好的专属性、精密性及准确度,可用于测定人凝血因子Ⅷ中的氨基酸含量。     

18％咪鲜·松脂铜乳油中咪鲜胺的分析

采用10％硫化钠溶液作沉淀剂,以排除松脂酸铜对咪鲜胺气相色谱分离的干扰,用内标溶液萃取咪鲜胺,并控制有机相的pH值在7．5左右,使用30m×0．53mm×1．0μmSE-54（交联）毛细管柱和FID检测器,对有机相中的咪鲜胺进行气相色谱分离,内标法定量。方法标准偏差〈0．2％,变异系数〈1．0％,平均回收率为99．83％,线性相关系数为0．9995。     

Ion Exchange Behavior of Selected Elements on Chelex 100 Resin

Abstract

Ion exchange behavior of some selected elements on Chelex 100 ion exchange resin in weakly acidic medium has been investigated. The acidity and the concentration of the supporting electrolyte have considerable influence on the sorption of metal cations by the ion exchanger. Column experiments have revealed that elution of cobalt and zinc in the definite pH range exhibits certain deviation compared to the other examined elements, resulting in doubly peaked elution curve. Apart from the commonly known cation (chelating) exchange function, under appropriate conditions Chelex 100 can also act as an anion exchanger. Ion exchange behavior of mercury in diluted hydrochloric acid medium is an illustration of amphoteric character of this resin. Two regions of pH can be distinguished, which correspond to the specified sorption mechanism of the metal by Chelex 100. In practical aspect, the use of Chelex 100 for the separation of trace amounts of several selected elements is demonstrated.     

离子交换分离L-缬氨酸的传质动力学及动态穿透特征

为了探讨离子交换分离L-缬氨酸的传质动力学及动态穿透特征,讨论了不同类型树脂的分离效能,研究了传质动力学及控制步骤,分析了固定床动态传质行为。结果表明,苯乙烯型强酸阳离子交换树脂有较佳的分离效能,吸附容量是其他树脂的5~8倍、选择性α为1.3~1.8;中性(或弱酸性)时,L-缬氨酸呈两性离子形态,有利于离子交换吸附。苯乙烯型强酸阳离子交换树脂001×7吸附分离L-缬氨酸,符合准二级动力学模型,初期受颗粒内与液膜两扩散共同控制,中后期受多个因素影响。Thomas和Yoon-Nelson模型适合描述L-缬氨酸和L-亮氨酸的动态穿透行为;流速增加,平衡吸附容量qe、体积吸附量N0和操作时间τ递减;料液浓度增加,平衡吸附容量qe和体积吸附量N0增加,但操作时间τ减少;床层高度的影响与料液浓度的影响呈相反趋势,高径比宜在5以下。     

Synthesis of single‐walled carbon nanotubes cerium(IV) phosphate composite cation exchnager: Ion exchange studies and its application as ion‐selective membrane electrode for determination of Cd(II) ions

Single‐walled carbon nanotubes cerium(IV) phosphate composite cation exchanger was synthesized using sol−gel method. The ion‐exchange properties such as elution concentration, elution behavior and effect of temperature on ion exchange capacity were studied. The composite cation exchange material showed an ion‐exchange capacity (IEC) of 1.64 meq dry g⁻¹ of ion exchanger. The distribution studies revealed that the composite cation‐exchanger is highly selective for Cd(II) ions. The material was used as an electroactive component for the construction of a cadmium ion‐selective membrane electrode. The membrane electrode showed a Nernstian response for Cd(II) ions over a wide concentration range of 1 × 10⁻⁷−1 × 10⁻¹ M with a sub‐Nernstian slope of 27.429 mV per decade change in concentration of cadmium ions. The limit of detection was found to be 1 × 10⁻⁷ M. It possessed a fast response time 10 s and can be utilized for 130 days without any considerable divergence in response potential. The practical utility of membrane electrode was demonstrated by employing as an indicator electrode for the potentiometric titration of Cd(II) with ethylenediamine tetra acetic acid, disodium salt (EDTA). POLYM. COMPOS., 38:1005–1013, 2017. © 2015 Society of Plastics Engineers     

HAP合成中交换树脂与羟胺离子交换的影响因素

为寻找适宜合成高氯酸羟胺(HAP)的离子交换树脂,对不同交联度、不同形态的强酸性阳离子交换树脂与羟胺交换过程进行了研究,发现了树脂与羟胺交换的主要影响因素,优选出适宜合成HAP的交换树脂为001×7型。根据流出曲线计算了不同条件下硫酸羟胺(HAS)加料系数的取值范围,并讨论了HAS浓度及流速对交换过程的影响,确定HAS的较佳加料系数为1.2。     

Separation of uin- and multivalent cations and selective de-ionisation by a phosphonic cation exchanger

The phosphonic cation exchanger in its free acid form is able to remove multivalent cations even from neutral and medium acidic solutions of salts of strong acids completely, and is regenerated by a stoichiometric amount of a regenerating agent. It is therefore possible to separate multivalent cations from univalent cations in a simple way by means of a phosphonic cation exchanger, followed by a weakly basic anion exchange resin. This results in a selective or partial de-ionisation of solutions with an eventual recovery of multivalent cations using an economical regeneration dosage and with a minimum of waste.     

EDTA-stannic(IV)iodate: preparation, characterization and its analytical applications for metal content determination in real and synthetic samples

A new organic–inorganic cation exchanger EDTA-stannic(IV)iodate was synthesized. The materials possess good chemical and thermal stability. The exchanger was characterized on the basis of X-ray, TGA, FTIR, UV–Visible spectrophotometery and SEM studies. ion exchange capacity, pH titration, elution and distribution studies were also carried out to determine the primary ion exchange properties of the material. The SEM study confirms the fibrous nature of the material. The exchanger behaves as a monofunctional cation exchanger with ion exchange capacity of 1.30 meq/g for Na⁺ ions. The material can perform well upto the temperature of 500 °C and retains the 76.4% of ion exchange capacity. The material is fairly stable in dilute solutions of some common mineral acids, bases and organic solvents. The differential selectivity of metal ions on EDTA-stannic(IV)iodate has been utilized to perform analytically and industrially important binary separations.     

Dual-end functionalized magnesium organo-(phyllo)silicates via co-condensation and its antimicrobial activity

Organic–inorganic hybrid materials (organo-(phyllo)silicates) offer multiple functions with distinct properties. The design of mesolamellar talc-like organo-(phyllo)silicates composed of cation metal backbones with multiple organofunctionalities had significant benefits because the method is facile, environmentally benign and amenable to scale-up and processing. In this study, magnesium organo-(phyllo)silicate was synthesized using 3-aminoproyltriethoxysilane and phenyltriethoxysilane before characterization and yield optimization of the prepared organo-(phyllo)silicates, resulting in dual-end pendant functionalities with not only antimicrobial activities from amino groups but also thermal stability from phenyl groups. Exploiting the unique properties of organo-(phyllo)silicates, spun fibers were developed by organo-(phyllo)silicate/polymer melt blending to make a bacteriostatic toothbrush.     

Zinc selective nano‐hybrid cation exchanger carboxymethyl cellulose Zr(IV) tungstate: Sol‐gel synthesis,physicochemical characterization,and analytical applications

Nano‐hybrid cation‐exchanger, carboxymethyl cellulose Zr(IV) tungstate was synthesized in the presence of surfactant. Physicochemical properties like thermal stability, surface morphology, particle size, and composition were evaluated by using thermogravimetric analysis/diffrential thermal analysis/diffrential thermogravimetry (TGA/DTA/DTG), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission elctron microscopy (TEM), and energy dispersive X‐ray (EDX) techniques. The ion exchange properties such as ion exchange capacity, elution behavior, eluent concentration, thermal effects, and pH titration were also performed to validate ion exchange behavior of synthesized material. Incorporation of carboxymethyl cellulose into the matrices of inorganic gels of Zr(IV) tungstate resulted enhanced ion exchange capacity and better mechanical stability of nano‐hybrid cation exchanger. A series of experiments were carried out for selective separation of Zn(II) ions from aqueous solutions of two‐component mixtures of heavy metal ions such as Zn(II)‐Hg(II), Zn(II)‐Cd(II), Zn(II)‐Ni(II), and Zn(II)‐Mg(II). The distribution studies showed that the synthesized nano‐hybrid cation‐exchanger is highly selective to Zn(II) ions. POLYM. COMPOS., 38:2057–2066, 2017. © 2015 Society of Plastics Engineers     

Sol–gel synthesis,physicochemical characterization,and analytical applications of copper selective composite cation exchanger: Polyvinyl alcohol Ce(IV) phosphate

An organic–inorganic composite cation exchanger polyvinyl alcohol Ce(IV) phosphate was prepared by the sol–gel method. The composite cation exchanger was characterized by some physicochemical properties like FTIR, TGA/DTA/DTG, XRD, SEM, TEM, EDX, and ion exchange properties to validate the structure and the ion exchange behavior. Ion exchange parameters indicated that the composite material is suitable for column operation. The ion exchange capacity of the composite ion exchanger is higher than that of the inorganic counterpart which showed that the incorporation of organic polymer polyvinyl alcohol (PVA) is responsible for prevention of the leaching of inorganic ion exchanger thereby proving mechanical stability and enhanced ion exchange properties. The distribution studies showed the selectivity toward Cu(II) ions, a heavy toxic metal ion. It was also observed that the selectivity depended upon the nature and composition of contacting solvents. The binary separation of a mixture of heavy metal ions Cu(II)–Zn(II), Cu(II)–Cd(II), and Cu(II)–Ni(II) also achieved thus composite cation exchanger proved excellent material could be effectively utilized in the treatment of discharge from copper plating, copper alloy, copper batteries, and smelting industries, whereas outstanding thermal stability of this composite ion exchanger could be utilized for the treatment of wastewater having Cu(II) ions with high temperature such as power generation and desalination plants. This composite ion exchanger with outstanding properties have potential to deal with aquatic toxicology caused by Cu(II) ions in future. POLYM. COMPOS., 38:332–340, 2017. © 2015 Society of Plastics Engineers     

Ion-exchange equilibria of amino acids on strong-acid resins: Theory

Equations describing equilibrium uptake of neutral, acidic, and basic amino acids by strong-acid cation exchangers as a function of pH and concentrations of amino acid and added electrolyte or buffer are derived.