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1.
在80~400 K温区,用高精度全自动绝热量热仪测定了对氨基苯甲酸摩尔热容,得到摩尔热容随温度的变化的关系式为:  相似文献   

2.
8—羟基喹啉的高分子化及其应用展望   总被引:8,自引:0,他引:8  
综述了8-羟基喹啉的各种高分子化方法,介绍了其在分析,环境,材料等领域中的应用情况,并展望了其在有机电致发光领域和导电聚合物等领域中的应用前景,提出了一些与之相关的值得深入研究的问题。  相似文献   

3.
拟定了用负载8-羟基喹啉的活性炭对水中痕量铂(Ⅵ)进行预富集的方法,探讨了活性炭吸附钼(Ⅵ)及有机试剂的作用机理。在试验条件下,100mg活性炭负载8-羟基喹啉后可提高对钼(Ⅵ)的吸附效果,同时除去干扰离子,用吸光光度法测定水中痕量钼(Ⅵ),结果满意。  相似文献   

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在醚性介质中,碱性染料品红与亚硝醚粮重氦化,然后在碱性介质中与8-羟基喹啉偶联生成偶氮化合物。该偶氮化合物于电位-0.70V(vs.SCE)处有一灵敏的极谱波,波高与亚硝酸根浓度在7×10 ̄(-9)~5×10 ̄(-6)g/mL范围内呈线性关系,检测限为5×10 ̄(-9)g/mL。该方法用于人唾液中亚硝醚根的测定,结果满意。  相似文献   

7.
用精密自动绝热量热计测定了重铬酸钾晶体在100~390 K温区内的摩尔热容.实验结果表明在研究温度区间内重铬酸钾无相变和其它热反常现象发生,但其热容在不同的温度范围表现出不同的变化趋势.在100 K≤ T ≤ 275 K和350 K≤ T ≤390 K区间内,其热容随温度的升高明显增大,在275 K≤ T ≤350 K区间,其热容约为定值.将重铬酸钾摩尔热容实验值Cp,m(J•K-1•mol-1)拟合成温度T的多项式方程,在100 K≤ T ≤275 K,为Cp,m=0.0050T2-1.0320T+125.22; 275 K≤ T ≤ 350 K,为Cp,m=209.37; 350 K≤ T ≤390 K,为Cp,m= 0.0266T2-18.823T+3542.3.根据热力学函数关系式,从热容值计算出了298.15 K~ 400 K温区范围内每隔5 K的热力学函数值.  相似文献   

8.
8—羟基喹啉树脂的制备及应用研究进展   总被引:2,自引:0,他引:2  
本文总结了国内外关于8-羟基喹啉螯合树脂的制备方法,树脂性能及其应用。  相似文献   

9.
8-羟基喹啉铝掺杂聚乙烯基咔唑薄膜的光致发光及电致发光马於光,唐建国,沈家骢,刘式墉(吉林大学分子光谱与分子结构开放实验室,集成光电子学国家联合重点实验室,长春,130023)关键词聚合物,光致发光,电致发光,8-羟基喹啉铝某些有机染料作为波长转换介...  相似文献   

10.
在pH6.2的HAc-NaAc缓冲溶液中,有溴化十六烷基三甲基铵(CTMA8)存在下,Zr(Ⅳ)与7-碘-8-羟基喹啉-5-磺酸(H_2QSI)及EDTA形成了四元荧光配合物。其组成为:Zr:H_QSI:EDTA:CTMAB=1:1:1:3。据此建立了错的选择性好、灵敏度高的荧光测定方法。方法检测限为1.2ng/mL。锆的线性范围为1.6ng~1.0μg/mL。用于铜合金中微量锆的测定,结果令人满意。  相似文献   

11.
Hui Xu  Xiwen Zeng  Huiling Dai 《中国化学》2011,29(10):2165-2168
A new fluorescent chemosensor based upon 1,8‐naphthalimide and 8‐hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg2+, Ag+, Zn2+, Fe2+, Cd2+, Pb2+, Ca2+, Cu2+, Mg2+, and Ba2+) were investigated. It displayed fluorescence quenching with some heavy and transition metal (HTM) ions, and the quenching strongly depended on the nature of HTM ions.  相似文献   

12.
Specific heat capacities of a homogeneous ethylene-1-octene copolymer were measured by adiabatic calorimetry in the temperature range from 5 to 400 K (stepwise heating at averaged rates of approximately 1 to 34 K h–1, after cooling at rates in the range from 8 K h–1 to 4 K min–1). The glass transition takes place from roughly 205 to225 K and is centred around approximately 215 K. At the latter temperature, also the temperature drifts during the stabilisation periods are at maximum. Clearly, with devitrification above 215 K also melting sets in. Using two sets of reference data (one for branched and linear polyethylenes, BPE, and the other for strictly linear polyethylene, LPE)for completely crystalline and for completely amorphous material, the crystallinity of the polymer was calculated as a function of temperature, within the two-phase model. In heating, the crystallinity decreased from 0.254 to zero in the temperature range from 220 to 360 K, confirming earlier DSC heat capacity measurements. During the stabilisation periods, below325 K, negative drifts were observed, related to endothermic effects caused by melting. However, in the temperature range from 325 K up to the end melting temperature, 360 K, positive drifts were measured, reflecting exothermic effects. These are attributed to recrystallisation phenomena. The occurrence and amount of recrystallisation depend on the thermal history of the sample: slower cooling and a longer time spent at a temperature of annealing clearly diminish recrystallisation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
设计合成了4个8-羟基喹啉共轭联接芳香杂环化合物来研究它们在有机发光材料和荧光探针的潜在应用。用IR, 1H NMR, 13C NMR, MS, UV确认了这些新化合物的结构。测定了化合物1-4的荧光性质,发光衰变时间和量子产率,并用密度泛函方法研究了4个化合物的几何结构和荧光发射波长的关系。在调控骨髓间充质干细胞增殖以及清除DPPH自由基的活性测试结果表明,这些化合物具有促进小鼠骨髓间充质干细胞的增殖的活性及良好的抗氧化性。  相似文献   

14.
通过小样品精密自动绝热热量计测定了自己合成并提纯的腈菌唑 (C15H17ClN4) 在78 ~ 368K温区的低温摩尔热容。量热实验发现, 该化合物在363 ~ 372 K温区, 有一固-液熔化相变过程, 其熔化温度为 (348.800±0.06)K, 摩尔熔化焓、摩尔熔化熵及化合物的纯度分别为:(30931±11) J•mol-1、(88.47±0.02) J•mol-1•K-1和0.9941(摩尔分数)。用差示扫描量热(DSC) 技术对该物质的固-液熔化过程作了进一步研究,结果与绝热量热法一致。  相似文献   

15.
本文介绍了用FeCl3•6H2O和尿素为反应物,在不添加表面活性剂等添加剂的条件下,制备纳米流体(纳米颗粒悬浮液)的新方法。通过XRD和TEM表征技术,表明得到的固体样品是纺锤形的纳米β–FeOOH颗粒。由于反应体系中含有NH3分子,其中在N原子和Fe原子之间可能存在弱的相互作用,因此,可以获得稳定的β–FeOOH纳米流体。该体系超额热容的研究也支持这一观点。应用绝热量热仪测量了制备的固体β–FeOOH颗粒和其纳米流体在不同温度下的摩尔热容。建立了摩尔热容与温度的函数关系。由此可获得所研究样品的焓、熵等热力学函数相对于298 .15 K的改变量。  相似文献   

16.
The 7‐allyl‐ and 7‐(2‐methylvinyl)‐functionalized derivatives of 8‐hydroquinoline are synthesized by Claisen rearrangement and double bond rearrangement respectively. Then 7‐allyl‐8‐hydroquinoline (C) and 7‐(2‐methylvinyl)‐8‐hydroquinoline (D) are reacted with aluminum chloride to afford the corresponding tris‐(7‐allyl‐8‐hydroxyquinoline) aluminum complex (F) and tris‐(7‐(2‐methylvinyl)‐8‐hydroxyquinoline) aluminum complex (G). The photoluminescence of complex (F) or (G), compared with that of tris‐(8‐hydroxyquinoline) aluminum complex (E), all showed a red shift in emission wavelengths in different solvents, such as chloroform, hexane and ethanol. For two substituents containing an external double bond, the 2‐methylvinyl group gives a larger red shift in the emission wavelength than the allyl group. The X‐ray crystal structure indicates that 7‐(2‐methylvinyl)‐8‐hydroxyquinoline (D) is a trans‐isomer. The styrene and 7‐allyl‐8‐hydroxyquinoline copolymer, and the styrene and 7‐(2‐methylvinyl)‐8‐hydroxyquinoline copolymer are also reported. Further reactions of the copolymer are then performed by adding aluminum(III) chloride and ligands 8‐hydroxyquinoline. The spectroscopic characteristics of these aluminum(III) polymeric complexes are discussed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

17.
A sensitive and selective method for the determination of Sb3+ based on the formation of its complexes with 8‐hydroxyquinoline (HQ) and 8‐hydroxyquinoline‐5‐sulfonic acid (HQS) is proposed. The best analytical conditions are: pH 5.4 and 2.2 for HQ and HQS, respectively; CHQ from 15.0 to 25.0 µmol L?1 and CHQS from 70.0 to 200.0 µmol L?1. The detection limits are 100.0 and 14.0 ng L?1 (tacc=30 s) for Sb3+ with HQ and HQS, respectively. The method using HQS as ligand has a 2.2‐fold higher sensitivity than that with HQ and the former was chosen for Sb3+ determination.  相似文献   

18.
以苏糖酸与碳酸氢钾反应制得苏糖酸钾K(C4H7O5)·H2O,通过红外光谱、热重、化学分析及元素分析等对其进行了表征。用精密自动绝热热量计测量了该化合物在78K-395K温区的摩尔热容。实验结果表明,该化合物存在明显的脱水转变,其脱水浓度、摩尔脱水焓以及摩尔脱水熵分别为:(380.524 ± 0.093) K,(19.655 ± 0.012) kJ/mol 和 (51.618 ± 0.051) J/(K·mol)。将78K-362K和382K-395K两个温区的实验热容值用最小二乘法拟合,得到了两个表示热容随温度变化的多项式方程。以RBC-II型恒容转动弹热量计测定目标化合物的恒容燃烧能为(-1749.71 ± 0.91) kJ/mol,计算得到其标准摩尔生成焓为(-1292.56 ± 1.06) kJ/mol。  相似文献   

19.
Reaction of Ti(OCH2CH2OR)4 (R?CH3 and C2H5) with 8‐hydroxyquinoline in benzene at room temperature resulted in the formation of Ti(C9H6NO)2(OCH2CH2OR)2, characterized by IR, 1H‐NMR, UV and mass spectroscopies. The molecular structure of Ti(C9H6NO)2(OCH2CH2OCH3)2 has been determined by single‐crystal X‐ray structure analysis. The geometry at titanium is a distorted octahedron, with the nitrogen atoms of quinolinate occupying the trans position with respect to oxygens of the 2‐methoxyethoxy groups. The prepared quinolinate derivatives of titanium alkoxides are very stable towards hydrolysis and harsh conditions are required for hydrolytic cleavage. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

20.
通过小样品精密自动绝热量热计测定了合成并提纯的 4,6 二甲基 N 苯基 2 嘧啶胺 (嘧霉胺 )在 78~ 3 91K温区的摩尔热容 .量热实验发现 ,该化合物在 3 63~ 3 72K温区 ,有一固 -液熔化相变过程 ,经三次重复测量 ,得其熔化温度、摩尔熔化焓及摩尔熔化熵分别为 :( 3 70 78± 0 0 8)K ,( 2 1 2 3 3± 0 0 13 )kJ·mol-1 和 ( 5 7 2 7± 0 15 )J·mol-1 ·K-1 .通过分步熔化法得到该物质绝对纯样品的熔点为 3 71 0 3 1K .用差示扫描量热 (DSC)技术对该物质的固 -液熔化过程作了进一步研究 ,结果与绝热量热法一致  相似文献   

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