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1.
A new spongy adsorbent (PU-DTC) was prepared with a polyurethane (PU) adsorbent for removal of EDTA-Cu(Ⅱ) and EDTA-Ni(Ⅱ) from water. This new spongy adsorbent was characterized by using SEM and 13C NMR and FT-IR spectroscopy. Adsorption kinetic curve indicated that this new spongy adsorbent could quickly remove EDTA-Cu(Ⅱ) and EDTA-Ni(Ⅱ) from water, and adsorption isotherm also indicated that PU-DTC had high equilibrium adsorption capacity for EDTA-Cu(Ⅱ) and EDTA-Ni(Ⅱ).  相似文献   

2.
The novel chelating sponge modifed with hydroxamic acid groups was prepared by a grafting polymerization followed by a nucleophilic substitution reaction.Elementary analysis,SEM,FT-IR spectroscopy and XPS were used to characterize the spongy adsorbent(PVA-MA-HH).Adsorption isotherm study indicated that PVA-MA-HH had high equilibrium adsorption capacity for Cu2+.  相似文献   

3.
A new reduced molybdenum(Ⅴ) phosphate (H3dien)2(H2dien)2[NaMo12O24 (OH)6 (H2PO4)(HPO4)5(PO4)2]·nH2O(n= 10.92,dien = diethylenetriamine) has been synthesized under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. C16H96.84MO12N12NaO72.92P8 (Mr = 3046.73) crystallizes in the monoclinic system, space group P21/c with a = 13.3575(18), b = 21.907(3), c = 15.654(2) A, β= 110.22(2)°, V= 4298.4(10) (A)3, Dc = 2.354 g/cm3, Z = 2, μ(MoKα) = 1.966 mm-1, F(000) = 2990.4, the final R = 0.0357 and wR = 0.1086 for 8739 observed reflections with Ⅰ> 2σ(Ⅰ). It consists of sandwich-shaped cluster anions [Na{Mo6P4}2]10- held together into a three-dimensional supramolecular framework through intermolecular hydrogen-bonding contacts. A probe reaction of the oxidation of acetaldehyde with H2O2 showed that this compound has high catalytic activity in the reaction.  相似文献   

4.
在硫酸介质中,痕量砷(Ⅴ)能灵敏地催化过氧化氢和高碘酸钾氧化二甲苯蓝FF褪色的指示反应,研究了该催化反应的最佳条件与动力学参数,建立了一种新的测定痕量砷(Ⅴ)的方法.该法的线性范围0~4.0 μg/L As(Ⅴ),检出限为9.8×10-8 g/L,用于食品中砷(Ⅴ)的测定,结果满意.  相似文献   

5.
催化动力学光度法测定痕量钒(Ⅴ)的研究   总被引:2,自引:0,他引:2  
在乙酸介质中,痕量钒(Ⅴ)对过硫酸钾氧化1 (2 吡啶偶氮)\|2 萘酚(PAN)褪色的指示反应有灵敏的催化作用。研究了该催化反应的最佳实验条件和动力学参数,建立了一种测定痕量钒(Ⅴ)的新方法,其线性范围为0.0~40.0μg/L钒(Ⅴ),方法检出限为2.62×10-9g/mL。  相似文献   

6.
阻抑动力学光度法测定粮食中痕量砷(Ⅴ)   总被引:5,自引:0,他引:5  
彭欣  陈国树 《分析化学》2003,31(1):38-40
研究发现,在硫酸介质中,痕量砷(Ⅴ)能灵敏地阻抑铬(Ⅴ)催化高碘酸钾氧化间磺酸基偶氮氯膦褪色的指示反应.研究了阻抑褪色反应的最佳条件及动力学参数,建立了一种测定痕量砷(Ⅴ)的新方法.其测定范围为0.0~16 μg砷(Ⅴ)/L;检测限为4.0×10-7 g/L砷(Ⅴ).该法用于大米、黄豆、豌豆和玉米中痕量砷(Ⅴ)的测定,结果满意.  相似文献   

7.
A new molybdenum phosphate [Zn(Mov6P4O31H10)2(C4H14N3)2]·2C4H13N3·8H2O 1 (C4H13N3 = diethylenetriamine) has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction reveals that compound 1 crystallizes in the monoclinic, space group P21/n, a =13.1679(3), b = 22.1240(6), c = 13.6146(3) (A), β = 103.4847(7)°, V = 3856.95(16) (A)3,C16H90N12O70P8ZnMo12, Mr = 3035.41, Z = 2, Dc = 2.614 g/cm3, μ = 2.483 mm-1, F(000) = 2968, S = 1.014, the final R = 0.0196 and wR = 0.0506 for 7486 observed reflections (I > 2σ(Ⅰ)). Compound 1 consists of two identical rings of six edge-sharing MoO6 octahedra interconnected by one ZnO6 octahedron, whereas the PO4 tetrahedra which share their apices with the MoO6 octahedra are only located on one side of each Mo6 ring. The 2-charge of polyanion [Zn(Mov6P4O31H10)2]2- unit is compensated in the crystal by two mono-protonated diethylenetriamines (C4H14N3)+. By hydrogen bonding interactions the polyanion of compound 1 is interconnected to form pseudo three dimensional molybdophosphate. Other characterizations by elemental analyses, IR spectrum and fluorescent spectrum are also described.  相似文献   

8.
建立了含多种金属离子和小分子配体组成的多相Np(Ⅴ)体液平衡模型。模拟研究了Np(Ⅴ)在胃液、汗液、组织液、细胞液和尿液中的形态分布。结果表明:胃液中,当[Np]为1×10-15mol.L-1~1×10-3mol.L-1时,Np(Ⅴ)以NpO2 形态存在。汗液中,当[Np]=1×10-6mol.L-1时,Np(Ⅴ)以NpO2 形态存在,当[Np]=1×10-3mol.L-1,pH4.2~5.0时,主要以NpO2 形态存在;随着pH升高,Np(Ⅴ)逐渐以固相Np2O5为主,到pH7.0时,Np2O5含量达99%。组织液中,当[Np]<4×10-6mol.L-1时,Np(Ⅴ)以NpO2CO3-、NpO2 和NpO2HPO4-形态存在,随[Np]增高,固相NaNpO2CO3逐渐占据主导地位,当[Np]=1×10-4mol.L-1时,固相含量达100%。当[Np]=1×10-3mol.L-1时,随组织液中添加的EDTA的浓度增加,固相含量逐渐降低,当[EDTA]=0.0085 mol.L-1时,已无固相Np(Ⅴ)形态。细胞液中,当[Np]=1×10-6mol.L-1时,Np(Ⅴ)以NpO2CO3-、NpO2 和NpO2HPO4-形态存在;当[Np]=1×10-3mol.L-1时,主要以固相Np2O5存在,但在巨噬细胞极低pH值的细胞液中以NpO2 形态存在。尿液中,当[Np]=1×10-6mol.L-1时,Np(Ⅴ)以NpO2 和NpO2HPO4-两种形态存在;当[Np]=1×10-3mol.L-1,pH>5.0时,随pH升高,固相Np2O5含量增加并逐渐占主导地位,但当pH<5.0时,Np(Ⅴ)主要以NpO2 形态存在,提示可降低尿液pH值促进肾脏Np(Ⅴ)排出。  相似文献   

9.
Titanium nitride nanowires (TiN NWs) were directly prepared on a Ti foil by a hydrothermal method followed by nitridation in ammonia atmosphere. The composition, microstructure, and electrochemical properties of the TiN NWs were characterized using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry(CV), and electrochemical impedance spectroscopy (EIS). The results show that the nanowires have diameters of 20-50 nm and are 5 μm long. The surfaces of the TiN NWs comprise Ti-N, Ti-O, and O-Ti-N chemical states. The electrochemical activity and reversibility for the electrode processes of Ⅴ(Ⅱ)/Ⅴ(Ⅲ) couple on the TiN NWs are significantly improved due to the introduced Ti-N, Ti-O, and O-Ti-N chemical states. The transfer resistance for the cathodic reduction of Ⅴ(Ⅲ) on the TiN NWs is about 20 times and 10 times smaller than on TiO2 NWs and graphite electrodes, respectively. The rate constant of charge transfer on the TiN NWs electrode was determined to be 5.21×10-4 cm·s-1, which is about 5 times larger than the rate constant on graphite electrodes (9.63×10-5 cm·s-1).  相似文献   

10.
The presence of pathogenic bacteria in water is one of the important health concerns in the world. Herein, we report a new high-performance environmentally friendly poly (urethane-imide) (PUIm) containing β-cyclodextrin (β-CD) in its backbone to adsorb bacteria from water samples with significant heat resistance. New PUIm was prepared by bonding a diisocyanate as a new cross linking agent to β-CD and magnetic nanoparticles (MNPs). The effects of concentrations of bare polymer and polymer bounded to iron nanoparticles and contact times on the adsorption of staphylococcus aureus and Escherichia coli were considered at physiological pH. The adsorption capacity of this polymer is increased by binding it to MNPs and in addition it is possible to separate the polymer from aqueous sample with external magnetic field. A filter was also provided from polymer attached to iron nanoparticles and high percentages of bacteria were removed after filtering the real wastewater.  相似文献   

11.
以La(OH)_3为原材料,探究其对水中As(Ⅲ)和As(Ⅴ)的吸附性能,并考察吸附剂投加量、p H值、初始浓度及温度对As(Ⅲ)和As(Ⅴ)吸附效果的影响。在单因素初步实验基础上,采用响应面法对La(OH)_3吸附水中As(Ⅲ)和As(Ⅴ)过程进行优化,并研究等温吸附及吸附动力学、热力学特性。结果表明,水中As(Ⅲ)和As(Ⅴ)的最佳去除条件分别为:投加量为0.437g和0.469g,p H值为4.365和3.672,初始浓度为106.716mg/L和108.65mg/L,该条件下As(Ⅲ)和As(Ⅴ)的去除率分别达71.68%和99%以上,且相同条件下As(Ⅴ)的去除效果要优于As(Ⅲ)。等温吸附及动力学拟合结果表明,As(Ⅲ)和As(Ⅴ)的吸附等温线均符合Freundlich模型,相同条件下As(Ⅴ)优于As(Ⅲ)的吸附效果,As(Ⅴ)在200mg/L时的吸附量是As(Ⅲ)的1.43倍,吸附过程均遵循准二级动力学模型,吸附过程为吸热且非自发反应过程。  相似文献   

12.
钒(Ⅴ)催化溴酸钾氧化铍试剂Ⅲ的反应及其应用   总被引:4,自引:0,他引:4  
基于在硫酸介质中钒(Ⅴ)催化溴酸钾氧化铍试剂Ⅲ的反应建立了测定痕量钒(Ⅴ)的新方法,研究了试剂浓度条件,讨论了反应机理,方法线性范围是0~0 50ng mL,检出限为7 0×10-12g mL,方法已用于矿泉水及蔬菜中钒的测定。  相似文献   

13.
基于硫酸介质中,柠檬酸作活化剂,钒(Ⅴ)、铬(Ⅵ)催化氨酸钾氧化鸡冠花红褪色的反应,建立了催化光度同时测定痕量钒(Ⅴ)、铬(Ⅵ)的新方法。研究了影响反应速率的最佳条件。本法测定钒(Ⅴ)、铬(Ⅵ)的线性范围分别为 0~ 8μm/L和0~0.6mg/L;检出限分别为1.79×10-7g/L和2.36×10-5g/L。用于测定环境水样、钢样及废水中的钒(Ⅴ)、铬(Ⅵ),结果令人满意。  相似文献   

14.
氢化物发生-原子吸收光谱法测定中药中砷(Ⅲ)和砷(Ⅴ)   总被引:14,自引:1,他引:14  
本文用氢化物发生(HG)-原子吸收光谱法(AAS)测定中药中的三价砷及五价砷。在pH5.6~6.0时,砷(Ⅲ)与硼氢化钾作用生成气态氢化物,而砷(Ⅴ)不发生反应;在2mol/L盐酸溶液中,用硫脲和抗坏血酸还原砷(Ⅴ)为砷(Ⅲ),同法测总砷,用差减法求得砷(Ⅴ)含量。方法检出限为7.5μg/L,RSD为1.45%。回收率为89.2%~114.6%。利用本方法成功地对六种中成药中的砷进行了形态分析。  相似文献   

15.
用氢化物发生-原子荧光光谱法测定环境水样中的砷(Ⅲ)和砷(Ⅴ),在0~100μg/L范围内砷的浓度与荧光强度呈线性关系,相关系数r=0.9999.测定结果的相对标准偏差为0.7%,检出限为0.08μg/L.与二乙氨基二硫代甲酸银光度法进行比对,经F检验和t检验,两种方法无显著性差异.  相似文献   

16.
建立了高效液相色谱-氢化物发生-原子荧光光谱法测定As(Ⅲ)和As(Ⅴ)的分析方法。通过在载流HCl中加入硫脲使经色谱柱分离后的As(Ⅴ)在线还原为As(Ⅲ),使As(Ⅴ)以As(Ⅲ)的形式与Na BH4进行反应,结果等浓度的As(Ⅴ)和As(Ⅲ)可以获得近似相同的荧光信号,有效地提高了方法检出As(Ⅴ)的能力。  相似文献   

17.
研究了线性扫描伏安法中钒(Ⅴ)的吸附溶出催化行为体系,借以分析环境、食品和生物样品。钒浓度与峰电流在10~(-2)~10~(-12)mol/L间按数量级分段成线性关系。最低检出限为6×10~(-13)mol/L,相对标准偏差在8%以下,干扰较少。  相似文献   

18.
任蕤  杨频 《中国化学》1999,17(6):625-636
Hydrolysis of DNA is an important enzymatic reaction , but it is exceedingly difficult to mimic in the laboratory because of the stability of hydrolysis of DNA. In this paper, the cleavage activity of complexes formed between Cu(Ⅱ) and four different amino acid or amino acid methyl ester on DNA is studied by gel elec-trophoresis. It is found that DNA could be cleaved by Cu(Ⅱ)-L-His and Cu(Ⅱ)-L-His methyl ester complexes and the efficiency of cleavage is largely dependent on the metal ion-to-ligand ratio. Further experiments show that the cleavage of DNA mediated by Cu(Ⅱ)-L-His complexes occurs via a hydrolytic mechanism and the active chemical species that affects DNA cleavage is proposed to be MI2H and ML2H22 .  相似文献   

19.
建立了As(Ⅲ)、As(V)的树脂分离 氢化物 原子荧光光谱分析方法。利用717阴离子交换树脂选择性的吸附水中的As(Ⅴ),从而实现了对水样中As(Ⅲ)和As(Ⅴ)的分离。考察了溶液的pH和流速以及洗脱剂浓度等条件对分离效果的影响,同时研究了仪器的工作条件、KBH4质量浓度和介质浓度对砷原子荧光强度的影响,并对测定砷时共存离子的干扰和消除进行了探讨。在最佳工作条件下,砷的检出限为0.096μg L,相对标准偏差为2.1%,将该方法应用于水样分析,其回收率为94.7%~107.9%。  相似文献   

20.
Poly(vinylpyridine) WH-225 resin was prepared and characterized.Compared with the commercial hypercrosslinked adsorbent NDA-100 and macroporous adsorbent XAD-4 resins,the newly synthesized poly(vinylpyridine) WH-225 resin exhibited the highest adsorption capacity toward SIPA from aqueous solution.  相似文献   

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