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11.
A novel reactive polycarboxylic acid dye was synthesized by the reaction of polymaleic anhydride(PMA) with 3-methyl-1-(4- sulfonylphenyl)-4-(4-aminophenylazo)-2-pyrazoline-5-one.The structure of the novel dye was characterized by FTIR,UV-vis and 13C NMR spectra.The dyeing properties of dye on cotton were tested,and the novel dye possessed high fixation and good fastness.  相似文献   
12.
Summary The direct esterification and gas chromatographic analysis of aromatic carboxylic acids as n-butyl esters is described.Derivatization is performed in aqueous solution with n-butanol in the presence of sulfuric acid. The butyl esters of benzoic, phthalic, hemimellitic, trimellitic, trimesic and pyromellitic acids permit their gas chromatographic separation from each other and from fatty acids and alipatic dicarboxylic acids. At mole ratios of [H2O]/ [n-BuOH]0.04 the water present does not interfere with the esterification reaction. At mole ratios above 0.04 anhydrous sodium sulfate is used for binding the water, at mole ratios of [Na2SO4 anh.]/[H2O]=0.25–0.75.  相似文献   
13.
介绍了普通陶瓷减水剂的研究背景,简要分析了新型聚羧酸系陶瓷减水剂及复配产品的研究现状、目前存在的问题及发展前景。  相似文献   
14.
合成了两种金属配合物{[Cu2(pztc)(4,4'-bpy)(H2O)4]·6H2O}n (1),{(H2bpe)[Cd(pztc)(H2O)2]·2.5H2O}n (2)(H4pztc=吡嗪-2,3,5,6-四甲酸,bpy=4,4'-联吡啶,bpe=1,2-二(4-吡啶基)乙烯),测定了其晶体结构,并对其进行了红外光谱、荧光光谱和热重分析等表征。两种配合物均为二维层状结构,但其中吡嗪四酸的配位方式不同。配合物2具有蓝色的荧光,最大荧光发射峰在475 nm。测试了配合物1的电子顺磁共振谱,结果显示Cu2+的特征谱带。  相似文献   
15.
A new polycarboxylic (PC) acid was prepared from copolymerization of 2-methyl-1-butylene alcohol polyoxyethylene ether (HPEG), acrylic acid (AA), and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and used as a high-performance dispersant in low-rank coal-water slurry (CWS). The optimized conditions are as follows: the reaction temperature is 80°C, the mole ratio of HPEG, AA, and AMPS is 1:3:0.3, and the inherent viscosity of PC polymer is 49.26 ml/g. The molecule structure of PC polymer was characterized by means of FTIR. Moreover, the apparent viscosity, static stability, and rheological property of CWS with the concentration of 63.0 and 65.0 wt% were all determined by adding PC hyper-dispersant or naphthalene sulfonate-formaldehyde (NSF) condensate dispersant at 0.5 wt% dosage. The result shows that PC dispersant has better properties than commercial NSF product in low-rank CWS. The effect was well rationalized by a combination of electrostatic repulsion force, wetting property, and steric hindrance provided by PC polymer.  相似文献   
16.
合成了1,4,7,10-四氮杂-环十二烷-1,4,7,10-四乙酸(H_4DOTA)配体,在水溶液中培养了Na[Ln(DOTA)·H_2O]·3H_2O(Ln=Er,Yb)配合物单晶,测定了其热谱和红外光谱,用X射线衍射方法测定了Na[Er(DOTA)·H_2O]·3H_2O的晶体结构,属正交晶系,空间群P2_12_12_1,Z=4,晶胞参数:α=1.5795(8)nm,b=1.5777(8)nm,c=0.9142(5)nm,V=2.278(3)nm~3,配合单元中铒为九配位,其配位多面体为单冠四方反棱柱体。  相似文献   
17.
稀土氮杂大环多羧酸配合物Na[Ln(DOTMA)(H_2O)]·2H_2O的合成与表征陈德福,金天柱(北京大学稀土材料化学及应用国家重点实验室,北京,100871)关键词稀土,氮杂大环多羧酸,配合物核磁共振成像技术已成为肿瘤和其它病变组织的临床诊断及生...  相似文献   
18.
Six two‐dimensional (2D) coordination polymers (CPs), namely, poly[{μ5‐3,3‐[(5‐carboxylato‐1,3‐phenylene)bis(oxy)]dibenzoato‐κ6O1:O1′:O3,O3′:O5:O5′}bis(N,N‐dimethylformamide‐κO)lanthanide(III)], [Ln(C21H11O8)(C3H7NO)2]n, with lanthanide/Ln = cerium/Ce for CP1 , praseodymium/Pr for CP2 , neodymium/Nd for CP3 , samarium/Sm for CP4 , europium/Eu for CP5 and gadolinium/Gd for CP6 , have been prepared by solvothermal methods using the ligand 3,3′‐[(5‐carboxy‐1,3‐phenylene)bis(oxy)]dibenzoic acid (H3cpboda) in the presence of Ln(NO3)3. The complexes were characterized by single‐crystal X‐ray and powder diffraction, IR spectroscopy, elemental analysis and thermogravimetric analysis (TGA). All the structures of this family of lanthanide CPs are isomorphous with the triclinic space group P and reveal that they have the same 2D network based on binuclear LnIII units, which are further extended via interlayer C—H…π interactions into a three‐dimensional supramolecular structure. The carboxylate groups of the cpboda3? ligands link adjacent LnIII ions and form binuclear [Ln2(RCOO)4] secondary building units (SBUs), in which each binuclear LnIII SBU contains four carboxylate groups from different cpboda3? ligands. Moreover, with the increase of the rare‐earth Ln atomic radius, the dihedral angles between the aromatic rings gradually increase. Magnetically, CP6 shows weak antiferromagnetic coupling between the GdIII ions. The solid‐state luminescence properties of CP2 , CP5 and CP6 were examined at ambient temperature and CP5 exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.53, 0.31), with luminescence quantum yields of 22%. Therefore, CP5 should be regarded as a potential optical material.  相似文献   
19.
合成了两种金属配合物{[Cu2(pztc)(4, 4'-bpy)(H2O)4]·6H2O}n (1), {(H2bpe)[Cd(pztc)(H2O)2]·2.5H2O}n (2)(H4pztc=吡嗪-2, 3, 5, 6-四甲酸, bpy=4, 4'-联吡啶, bpe=1, 2-二(4-吡啶基)乙烯), 测定了其晶体结构, 并对其进行了红外光谱、荧光光谱和热重分析等表征。两种配合物均为二维层状结构, 但其中吡嗪四酸的配位方式不同。配合物2具有蓝色的荧光, 最大荧光发射峰在475 nm。测试了配合物1的电子顺磁共振谱, 结果显示Cu2+的特征谱带。  相似文献   
20.
Cotton fabrics are modified by means of polycarboxylic acids (PCA) in combination with an inorganic catalyst in order to impart durable press properties. To evaluate the effectiveness of cyclic PCA, 100% cotton fabrics were treated with 1,2,3,4,5,6-cyclohexanehexacarboxylic acid (CH-HCA), 1,3,5-cyclohexanetricarboxylic acid (CH-TCA), 1,2,3,4-cyclopentanetetracarboxylic acid (CP-TCA), and 1,2,3,4-tetrahydrofurantetracarboxylic acid (THF-TCA) in combination with sodium hypophosphite (SHP) as catalyst. The amount of PCA that reacted with the cellulosic material was determined by means of isocratic HPLC (Aminex HPX-87-H). The results clearly indicate that the cyclic PCA are less effective in respect of durable press performance. CH-TCA does not react with the cellulosic material thus confirming the assumption that the crosslinking reaction between PCA and the cellulose proceeds via a five-membered cyclic anhydride.  相似文献   
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