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1.
A new one-pot, efficient three-component condensation of benzaldehydes, 2-naphthol, and carbamates in the presence of silica supported sodium hydrogen sulfate as an effective heterogeneous catalyst for the synthesis of novel 1-carbamato-alkyl-2-naphthol derivatives under solvent-free conditions is described. The present methodology offers several advantages, such as high yields, short reaction times, and very easy workup.  相似文献   

2.
Hexamethylenetetramine-functionalized silica-coated nano-Fe3O4 particles (MNPs@Hexamethylenetetramine) were prepared as a reusable heterogeneous catalyst using a facile process. The catalyst was synthesized and characterized using infrared, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and vibrating sample magnetometer. This magnetic nanocatalyst was employed as an efficient, reusable, and environmentally benign heterogeneous catalyst for the synthesis of amidoalkylnaphthol derivatives from a one-pot three-component condensation reaction of beta-naphthol, aldehydes, and amides in good to excellent yields, Moreover, this catalyst can be easily recovered by using a magnetic field and directly reused for at least seven runs without sign ificant loss of its activity.  相似文献   

3.
以α-甲基丙烯酸为功能单体,在氯仿溶剂中,利用传统的分子印迹聚合物制备技术,成功合成了偶氮类分子1-(2-吡啶偶氮)-2-萘酚的印迹聚合物。用红外光谱、紫外光谱等技术对聚合物进行了表征测定,并用平衡结合实验研究了聚合物的吸附特性。  相似文献   

4.
A series of three-component reactions has been carried out using HClO4-SiO2 as a versatile heterogeneous catalyst. A series of new and novel N-protected 1-aminoalkyl-2-naphthol derivatives have been prepared under thermal solvent-free reaction conditions. In all cases, the reaction conditions were very simple and high-yielding.  相似文献   

5.
应用碳包覆固相法合成锂离子电池Li3V2(PO4)3正极材料.X射线衍射、扫描电子显微镜表征材料的结构和观察表面形貌.材料的电阻和电化学性能测试表明,碳包覆Li3V2(PO4)3材料可避免颗粒团聚,减小颗粒尺寸,提高材料电导率,改善其电极的电化学性能.  相似文献   

6.
采用高温固相法合成了新型特效Na离子吸附剂Li1 xLaxZr2-x(PO4)3.对不同条件下合成的吸附剂进行了XRD结构分析以及SEM分析和IR分析,并对其吸附性能进行了测定.XRD结构分析表明,当x≤0.4时均能得到与LiZr2(PO4)3相同的晶体结构.SEM分析表明,合成的吸附剂分散性好,粒径范围在5~20μm之间.吸附性能测定结果表明,少量La的加入使Li1 xLaxZr2-x(PO4)3对Na离子产生了特效吸附作用,La离子掺杂是改善LiZr2(PO4)3吸附性能的一条有效途径,当x=0.4时,在pH值为10.0~11.0条件下,Li1 xLaxZr2-x(PO4)3的吸附容量达到48.3mg/g.  相似文献   

7.
The present work has focused on the modification of multiwalled carbon nanotube with a ligand,l-(2-pyridylazo)-2-naphthol, and its potential application for the development of a new,simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd(Ⅱ).The analytical curve for Cd(Ⅱ) ions covered the linear range varying from 0.8 up to 220.4μgL-1.The limit of detection was found to be 0.1μgL-1,while the relative standard deviation(RSD) at 50.0μgL-1 was 1.8%(n=5).This modified electrode was successfully applied for determination of Cd(Ⅱ) in some water samples.  相似文献   

8.
By the reaction of 4-chlorobenzaldehyde with ethyl acetoacetate, malononitrile, and hydrazine hydrate, 6-amino-4-(4-chlorophenyl)-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile was prepared and then reacted with salicylaldehyde and CoCl2·6H2O to produce nano-Co-[4-cholorophenyl-salicylaldimine-methylpyranopyrazole]Cl2 (nano-[Co-4CSMP]Cl2). The prepared nano-Schiff base complex was reported for the first time and fully characterized by Fourier transform-infrared spectroscopy, thermal gravimetric analysis, differential thermal gravimetric analysis, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and Brunner–Emmett–Teller analyses and applied as an efficient catalyst for the synthesis of some 1-amidoalkyl-2-naphthol derivatives.  相似文献   

9.
The formation of the Tm(III) complex with 1-(2-pyridylazo)-2-naphthol (PAN or HL) in aqueous-methanol mixtures (50 and 75%v/v) was studied by a spectrophotometric method. The equilibrium constant for the complexing reaction and the stability constant of the complex TmL 2+ were calculated. The solvent extraction of Tm(III) byPAN in carbon tetrachloride from aqueous and aqueous-methanol phase was investigated. The extraction equilibrium constants and two-phase stability constants for the TmL 3 and the TmL 3(MeOH)3 complexes were evaluated. It was confirmed that the addition of methanol to the aqueous phase (above 25%v/v) causes a synergistic effect.
Extraktion von Ionen der Seltenerdmetalle mit 1-(2-Pyridylazo)-2-naphthol (PAN), 5. Mitt.: Komplexbildung und Gleichgewichtsverteilung von Thulium (III) mitPAN
Zusammenfassung Die Bildung des Komplexes von Tm(III) mit 1-(2-Pyridylazo)-2-naphthol (PAN oder HL) in Wasser-Methanol Mischungen (50 und 75%v/v) wurde mit einer spektrophotometrischen Methode untersucht. Die Gleichgewichtskonstante für die Reaktion der Komplexbildung und die Stabilitätskonstante des Komplexes TmL 2+ wurden berechnet. Die Extraktion von Tm(III) mittelsPAN in Kohlenstofftetrachlorid aus Wasser oder Wasser-Methanol wurde untersucht. Die Werte der Extraktionsgleichgewichtskonstante sowie der zweiphasigen Beständigkeitskonstante für die Komplexe TmL 3 und TmL 3(MeOH)3 wurden berechnet. Es wurde festgestellt, daß die Zugabe von Methanol zur wäßrigen Phase (25%v/v) einen synergistischen Effekt hat.
  相似文献   

10.
A simple procedure based on magnetic nanoparticles has been developed for analytical purposes. In this method, 1-(2-pyridylazo)-2-naphthol (PAN)-modified magnetic nanoparticles (MNPs) were used for separation and pre-concentration of manganese(II) ions from aqueous samples. This method combines the use of a solution solvent with separation of magnetic nanoparticles from sample solution using a magnet. The influence of different parameters, such as amount of extractant (PAN) loaded on the nanoparticles, pH of solution, adsorption time, amount of modified nanoparticle, type and amount of eluents for desorption of manganese from magnetic nanoparticles were evaluated. The effect of various cationic and anionic interferences on the percentage recovery of manganese was also studied. Manganese ions were adsorped from a solution at pH 9.5 and desorbed from nanoparticles with 10?mL of DMSO?:?HNO3 (1?:?1, v/v). The detection limit of the proposed method was found to be 0.11?µg?L?1. The method was employed to recover and determine the level of manganese in different water samples.  相似文献   

11.
The formation ofPAN complexes in the systemsLn(III)—PAN—alcohol-water (where:Ln(III)=Ho, Lu and alcohol=ethanol,n-propanol,iso-propanol) was investigated by a spectrophotometric method. Equilibrium constants for the reactionLn 3+ + HLLnL 2+ + H+ (HL=PAN) and stability constants of complexesLnL 2+ were calculated.
Untersuchungen zur Komplexbildung von Ho(III) und Lu(III) mit 1-(2-Pyridylazo)-2-naphthol (PAN) in alkoholisch-;wä\rigen Lösungen
Zusammenfassung Die Bildung der Komplexe vonPAN in den SystemenLn(III)—PAN—Alkohol-Wasser (Ln(III)=Ho, Lu; Alkohol=Ethanol,n-Propanol,iso-Propanol) wurde mit einer spektrophotometrischen Methode untersucht. Die Gleichgewichtskonstanten der ReaktionenLn 3+ + HLLnL 2+ + H+ (HL==PAN) und die Stabilitätskonstanten der KomplexeLnL 2+ wurden berechnet.
  相似文献   

12.
The complexation reactions between Ni(2+), Co(2+) and Zn(2+) metal ions with PAN in methanol (MeOH), acetonitrile (AN) and dimethyl sulfoxide (DMSO) were studied using a spectrophotometric method. The stability constants of the resulting complexes were determined from computer fitting absorbance mole-ratio data. The results revealed that the stability constants of complexes are varying in order of Ni(2+)相似文献   

13.
单斜Li3V2(PO4)3/C复合材料的制备及其电化学性能   总被引:1,自引:0,他引:1  
以LiOH·H2O、V2O5、H3PO4和蔗糖为原料,采用软化学法制备了锂离子电池正极材料Li3V2(PO4)3/C.通过X射线衍射(XRD)、扫描电镜(SEM)对产物的结构和形貌进行表征,采用恒电流充放电、电化学阻抗考察了产物的电化学性能.结果表明.当煅烧温度达到700℃时,杂质相衍射峰消失,所得的样品为纯相的单斜Li3V2(PO4)3.颗粒粒度为1~2 μm;在3.0~4.5 V电压范围内以0.2C倍率充放电,首次放电比容量达到148.2 mAh·g-1,第50次循环比容量仍为144 mAh·g-1,容量保持率为97%,具有良好的循环性能;另外,样品还具有很好的倍率性能和高温性能.  相似文献   

14.
The formation ofPAN complexes in the systems:Ln(III)—PAN—alcohol—water [whereLn(III) = Pr, Nd, Sm, Eu, Gd, Tb, alcohol - ethanol andLn(III) = Eu, alcohol =n-propanol, isopropanol] was investigated by a spectrophotometric method. Equilibrium constants for the reactionLn 3++HLLnL 2++H+ (HL =PAN) and stability constants of complexesLnL 2+ are reported.
Komplexbildung einiger Seltenerdmetalle mit 1-(2-Pyridylazo)-2-naphthol (PAN) in alkoholisch-wäßrigen Lösungen
Zusammenfassung Die Bildung der Komplexe vonPAN in den SystemenLn(III)—PAN—Alkohol—Wasser [Ln(III) = Pr, Nd, Sm, Eu, Gd, Tb, Alkohol = Ethanol undLn(III) = Eu, Alkohol =n-Propanol, Isopropanol] wurde mit einer spektrophotometrischen Methode untersucht. Die Gleichgewichtskonstanten der ReaktionenLn 3++HLLnL 2++H+ (HL =PAN) und die Stabilitätskonstanten der KomplexeLnL 2+ wurden berechnet.
  相似文献   

15.
马同森  张顺利 《分析化学》1999,27(7):825-827
以十二烷基硫酸钠-溴代十六烷基三甲胺(SDS-CIMAB)复合微乳液为介质,对Co(Ⅱ)-1-(2-吡啶偶氮)-2-萘酚的显色反应条件进行了研究.结果表明该体系的λ_(max)=580nm,ε_(580)=3.4×10~4L·mol·cm~(-1),Co(Ⅱ)测定的线性范围为0~2.40mg/L.回收率在96%~103%之间,该法选择性好,用于蔬菜中Co(Ⅱ)含量的测定,得到了满意的结果.  相似文献   

16.
Interaction of 1-(2-pyridylazo)-2-naphthol (PAN) with [Mo(CO)6] in air resulted in formation of the tricarbonyl oxo-complex [Mo(O)(CO)3(PAN)], 1. The dicarbonyl complex [Ru(CO)2(PAN)], 3, was obtained from the reaction of [Ru3(CO)12] with PAN. In presence of triphenyl phosphine (PPh3), the reaction of PAN with either Mo(CO)6 or Ru3(CO)12 gave [Mo(CO)3(PAN)(PPh3)], 2, and [Ru(CO)2(PAN)(PPh3)], 4. All the complexes were characterized by elemental analysis, mass spectrometry, IR, and NMR spectroscopy. The thermal properties of the complexes were also investigated by thermogravimetry.  相似文献   

17.
<正>A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate(KH_2PO_4) under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective.  相似文献   

18.
A new polystyrene-divinylbenzene resin containing 1-(2-thiazolylazo)-2-naphthol (TAN) functional group was synthesized and its sorption behavior for 19 metal ions including Zr(IV), Hf(IV) and U(VI) was investigated by batch and column experiments. The chelating resin showed a high sorption affinity for Zr(IV) and Hf(IV) at pH 2. Some parameters affecting the sorption of the metal ions are detailed. The breakthrough and overall capacities were measured under optimized conditions. The overall capacities of Zr(IV) and Hf(IV) that were higher than those of the other metal ions were 0.92 and 0.87 mmol/g, respectively. The elution order of metal ions at pH 4 was evaluated as: Zr(IV)>Hf(IV)>Th(IV)>V(V)>Nb(V)>Cu(II)>U(VI)>Ta(V)>Mo(VI)>Cr(III)>Sn(IV)>W(VI). Quantitative recovery of most metal ions except Zr(IV) was achieved using 2 M HNO3. Desorption and recovery of Zr(IV) was successfully performed with 2 M HClO4 and 2 M HCl.  相似文献   

19.
娄太平  王家良 《物理化学学报》2007,23(10):1642-1646
锂离子传导材料LiTi2(PO4)3能在LiCl水溶液中高选择性地与Na+进行离子交换. 研究了NaCl 溶液中LiTi2(PO4)3上的Na/Li离子交换反应, 实验结果表明, 升高温度能显著提高LiTi2(PO4)3上的Na/Li交换反应速率, 其离子交换动力学规律可近似由JMAK(Johnson-Mehl-Aurami-Kalmogorav)方程描述. 对LiTi2(PO4)3在水和NaCl溶液中的溶解行为的研究结果表明, 升高温度能加快其在水中的溶解速率, pH值过大或过小及离子交换都会加剧LiTi2(PO4)3的溶解.  相似文献   

20.
A separation-preconcentration method based on supramolecular solvent ultrasonic-assisted liquid-phase microextraction (Ss-USA-LPME) for spectrophotometric determination of mercury as 1-(2-pyridylazo)-2-naphthol (PAN) chelates has been established. Red coloured Hg(II)-PAN hydrophobic complex was extracted into the supramolecular phase (1-decanol/THF) at pH 9.5. The extract was separated from aqueous phase by centrifugation, diluted with ethanol and determined by UV–Vis spectrophotometer at λmax = 560 nm. The influences of important analytical parameters such as pH, amount of PAN, 1-decanol and THF, sample volume and matrix effects for the quantitative recoveries were examined and optimised. Under the optimised experimental conditions, the amount of ligand, 1-decanol and THF were 1.0 × 104 M, 200 µL and 300 µL, respectively. The optimum time of ultrasonic bath and centrifugation were found as 2 min and 5 min. A linear calibration graph was obtained linearly in the concentration ranges of 8.31000 µg L?1. The preconcentration factor was obtained as 20. The limit of detection (LOD) was 2.6 µg L?1 with the relative standard deviation (RSD) of 2.4% for mercury (C = 100 µg L?1, n = 7). The validity of the developed Ss-USA-LPME technique was checked with a certified reference material of NIST 1641d. The presented method has been successfully applied to the determination of mercury in water samples.  相似文献   

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