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通过1-苯基-3-甲基-4-氯乙酰基-吡唑啉酮-5(PMCP)和氨基硫脲( TSC)缩合,形成了一种含NNS六元杂环的光致变色化合物(PMCP-TSC)。利用元 素分析,MS,”1H NMR,IR和UV光谱进行了表征。通过紫外可见光谱对它的光致 变色性质进行了研究,测出了光致变色反应的动力学常数。并用X线单晶衍射仪测 定了PMCP-TSC变色后的晶体结构,该晶体属单斜晶系,具有P2_1/c空间群,a = 0.105 10(2) nm, b = 0.150 61(3) nm, c = 0.993 70(10) nm, β = 107.890 (10)°, V = 1.496 9(4) nm~3, Z - 4, D_c = 1.417 Mg/m~3, μ = 0.232 mm~(- 1), F(000) = 672, R = 0.033 4, wR = 0.089 6。结构分析表明:其光致变色现 象是由于它在溶剂与光的共同作用下发生了从醇式到酮式的异构化。同时该化合物 经分子间氢键形成二聚体,又通过甲醇与本体分子之间的氢键使化合物形成具有三 维网络结构的超分子化合物。 相似文献
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本文研究了2-(-5-Br-2吡啶偶氮-5-二乙氨基)-酚与铑(Ⅲ)的显色反应。在pH为4.0的邻苯二甲酸氢钾缓冲液介质中,Rh(Ⅲ)与试剂形成稳定的橙红色络合物,其组成比为1:4,最大吸收波长为490nm,表现摩尔吸光系数为1.3×10 ̄5L·mol ̄(-1)·cm ̄(-1)。铑含量在0~4μg/10mL范围内服从比尔定律。 相似文献
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用凝胶法生长了标题配合物[NH_4(B15C5)_2][Cd(SCN)_3]的晶体,并对其进行了红外光谱,元素分析等各项物理性质的测试。经X射线单晶结构分析得到了配合物的全部晶体学数据:M_r=841.31,正交晶系,空间群P2_12_12_1,晶胞常数a=10.970(3),b=21.834(3),c=15.563(4),V=3727(3),Z=4,D_x=1.50g/cm ̄3,F(000)=1736,μ=7.09cm ̄(-1),R=0.070,R_w=0.063。结构分析结果表明,配阳离子[NH_4(B15C5)_2] ̄+和配阴离子[Cd(SCN)_3] ̄-间靠静电力结合成配合物。 相似文献
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含氟Y-Ba-Cu-O高温超导体稳定性与结构的研究 总被引:1,自引:0,他引:1
应用BaF2、CuF2和YF3分别部分代换BaO、CuO和Y2O3制得了一系列带有氟元素的Y-Ba-Cu-O高温超导体样品,其中BaF2代换BaO的摩尔量可达45%,样品的零电阻温度为82.5~93.5K。应用XRD、DTA、IR和化学方法研究了样品的结构和稳定性。初步实验结果表明,氟元素只有少量进入超导相,但含氟的Y-Ba-Cu-O超导体在水蒸气和二氧化碳中的稳定性则大大提高。 相似文献
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1-芳酰基-3-烷基-6-羟基-6-芳基富烯的合成焦纶基,董育斌,马玉道(山东大学应用化学研究所,济南,250100)关键词富烯,二茂铁,芳酰化,合成前文[1]曾报道过甲基锂、苯基锂与6,6-二烷基富烯加成物的芳酰化。为进一步探讨取代环戊二烯负离子的... 相似文献
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Yahia Lemmouchi Michael C. Perry Allan J. Amass Khirud Chakraborty Etienne Schacht 《Journal of polymer science. Part A, Polymer chemistry》2008,46(16):5363-5370
Biodegradable, triblock poly(lactide)‐block‐poly(ε‐caprolactone)‐block‐poly(lactide) (PLA‐b‐PCL‐b‐PLA) copolymers and 3‐star‐(PCL‐b‐PLA) block copolymers were synthesized by ring opening polymerization of lactides in the presence of poly(ε‐caprolactone) diol or 3‐star‐poly(ε‐caprolactone) triol as macroinitiator and potassium hexamethyldisilazide as a catalyst. Polymerizations were carried out in toluene at room temperature to yield monomodal polymers of controlled molecular weight. The chemical structure of the copolymers was investigated by 1H and 13C‐NMR. The formation of block copolymers was confirmed by NMR and DSC investigations. The effects of copolymer composition and molecular structure on the physical properties were investigated by GPC and DSC. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5363–5370, 2008 相似文献
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Mehmet Atilla Tasdelen Selim Beyazit Deniz Gunes Niyazi Bicak Pinar Tatar A. Levent Demirel Yusuf Yagci 《Journal of polymer science. Part A, Polymer chemistry》2011,49(18):4021-4026
The synthesis of poly(p‐phenylene methylene) (PPM)‐based block copolymers such as poly(p‐phenylene methylene)‐b‐poly(ε‐caprolactone) and poly(p‐phenylene methylene)‐b‐polytetrahydrofuran by mechanistic transformation was described. First, precursor PPM was synthesized by acid‐catalyzed polymerization of tribenzylborate at 16 °C. Then, this polymer was used as macroinitiators in either ring‐opening polymerization of ε‐caprolactone or cationic ring‐opening polymerization of tetrahydrofuran to yield respective block copolymers. The structures of the prepolymer and block copolymers were characterized by GPC and 1H NMR investigations. The composition of block copolymers as determined by 1H NMR and TGA analysis was found to be in very good agreement. The thermal behavior and surface morphology of the copolymers were also investigated, respectively, by differential scanning calorimetry and atomic force microscopy measurements, and the contribution of the major soft segment has been observed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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A new cyclic monomer, 2-oxo-3-methylene-5, 6-diphenyl-1, 4-dioxan, was synthesized. Thestructure of the intermediates and the monomer were determined by IR,~1H NMR,~(13)C NMR andelemental analysis. This new monomer is different from other cyclic monomers in this series,it isa solid (mp 108--109℃)and not very reactive, but still can undergo free radical ring-openingpolymerization. The free radical polymerization was carried out at 130℃. The structure of theresulting polymer was discussed and charaterized by IR, ~1H NMR, ~(13)C NMR and elementalanalysis. The molecular weight of the polymer was estimated by viscosity determination. 相似文献
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Ning Xu Rui Wang Fu‐Sheng Du Zi‐Chen Li 《Journal of polymer science. Part A, Polymer chemistry》2009,47(14):3583-3594
Amphiphilic, biodegradable block glycopolymers based on poly(ε‐caprolactone) (PCL) with various pendent saccharides were synthesized by combination of ring‐opening polymerization (ROP) and “click” chemistry. PCL macroinitiators obtained by ROP of ε‐caprolactone were used to initiate the ROP of 2‐bromo‐ε‐caprolactone (BrCL) to get diblock copolymers, PCL‐b‐PBrCL. Reaction of the block copolymers with sodium azide converted the bromine groups in the PBrCL block to azide groups. In the final step, click chemistry of alkynyl saccharides with the pendent azide groups of PCL‐b‐PBrCL led to the formation of the amphiphilic block glycopolymers. These copolymers were characterized by 1H NMR spectroscopy and gel permeation chromatography. The self‐assembly behavior of the amphiphilic block copolymers was investigated using transmission electron microscopy and atomic force microscope, spherical aggregates with saccharide groups on the surface were observed, and the aggregates could bind reversibly with Concanavalin A. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3583–3594, 2009 相似文献
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Yahia Lemmouchi Michael C. Perry Allan J. Amass Khirud Chakraborty Etienne Schacht 《Journal of polymer science. Part A, Polymer chemistry》2007,45(17):3975-3985
Biodegradable, amphiphilic, diblock poly(ε‐caprolactone)‐block‐poly(ethylene glycol) (PCL‐b‐PEG), triblock poly(ε‐caprolactone)‐block‐poly(ethylene glycol)‐block‐poly(ε‐caprolactone) (PCL‐b‐PEG‐b‐PCL), and star shaped copolymers were synthesized by ring opening polymerization of ε‐caprolactone in the presence of poly(ethylene glycol) methyl ether or poly(ethylene glycol) or star poly(ethylene glycol) and potassium hexamethyldisilazide as a catalyst. Polymerizations were carried out in toluene at room temperature to yield monomodal polymers of controlled molecular weight. The chemical structure of the copolymers was investigated by 1H and 13C NMR. The formation of block copolymers was confirmed by 13C NMR and DSC investigations. The effects of copolymer composition and molecular structure on the physical properties were investigated by GPC and DSC. For the same PCL chain length, the materials obtained in the case of linear copolymers are viscous whereas in the case of star copolymer solid materials are obtained with low Tg and Tm temperatures. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3975–3985, 2007 相似文献
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Mingxiao Deng Xuesi Chen Longhai Piao Xuefei Zhang Zhongli Dai Xiabin Jing 《Journal of polymer science. Part A, Polymer chemistry》2004,42(4):950-959
Biodegradable, amphiphilic, four‐armed poly(?‐caprolactone)‐block‐poly(ethylene oxide) (PCL‐b‐PEO) copolymers were synthesized by ring‐opening polymerization of ethylene oxide in the presence of four‐armed poly(?‐caprolactone) (PCL) with terminal OH groups with diethylzinc (ZnEt2) as a catalyst. The chemical structure of PCL‐b‐PEO copolymer was confirmed by 1H NMR and 13C NMR. The hydroxyl end groups of the four‐armed PCL were successfully substituted by PEO blocks in the copolymer. The monomodal profile of molecular weight distribution by gel permeation chromatography provided further evidence for the four‐armed architecture of the copolymer. Physicochemical properties of the four‐armed block copolymers differed from their starting four‐armed PCL precursor. The melting points were between those of PCL precursor and linear poly(ethylene glycol). The length of the outer PEO blocks exhibited an obvious effect on the crystallizability of the block copolymer. The degree of swelling of the four‐armed block copolymer increased with PEO length and PEO content. The micelle formation of the four‐armed block copolymer was examined by a fluorescent probe technique, and the existence of the critical micelle concentration (cmc) confirmed the amphiphilic nature of the resulting copolymer. The cmc value increased with increasing PEO length. The absolute cmc values were higher than those for linear amphiphilic block copolymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 950–959, 2004 相似文献
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J.‐T. Hong N.‐S. Cho H.‐S. Yoon T.‐H. Kim D.‐H. Lee W.‐G. Kim 《Journal of polymer science. Part A, Polymer chemistry》2005,43(13):2790-2799
A series of poly(trimethylenecarbonate‐ε‐caprolactone)‐block‐poly(p‐dioxanone) copolymers were prepared with varying feed rations by using two step polymerization reactions. Poly(trimethylenecarbonate)(ε‐caprolactone) random copolymer was synthesized with stannous‐2‐ethylhexanoate and followed by adding p‐dioxanone monomer as the other block. The ring opening polymerization was carried out at high temperature and long reaction time to get high molecular weight polymers. The monofilament fibers were obtained using conventional melting spun methods. The copolymers were identified by 1H and 13C NMR spectroscopy and gel permeation chromatography (GPC). The physicochemical properties, such as viscosity, molecular weight, melting point, glass transition temperature, and crystallinity, were studied. The hydrolytic degradation of copolymers was studied in a phosphate buffer solution, pH = 7.2, 37 °C, and a biological absorbable test was performed in rats. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2790–2799, 2005 相似文献
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Peng‐Fei Gou Wei‐Pu Zhu Ning Xu Zhi‐Quan Shen 《Journal of polymer science. Part A, Polymer chemistry》2008,46(19):6455-6465
Per‐2,3‐acetyl‐β‐cyclodextrin with seven primary hydroxyl groups was synthesized by selective modification and used as multifunctional initiator for the ring‐opening polymerization of ε‐caprolactone (CL). Well‐defined β‐cyclodextrin‐centered seven‐arm star poly(ε‐caprolactone)s (CDSPCLs) with narrow molecular weight distributions (≤1.15) have been successfully prepared in the presence of Sn(Oct)2 at 120 °C. The molecular weight of CDSPCLs was characterized by end group 1H NMR analyses and size‐exclusion chromatography (SEC), which could be well controlled by the molar ratio of the monomer to the initiator. Furthermore, amphiphilic seven‐arm star poly(ε‐caprolactone‐b‐ethylene glycol)s (CDSPCL‐b‐PEGs) were synthesized by the coupling reaction of CDSPCLs with carboxyl‐terminated mPEGs. 1H NMR and SEC analyses confirmed the expected star block structures. Differential scanning calorimetry analyses suggested that the melting temperature (Tm), the crystallization temperature (Tc), and the crystallinity degree (Xc) of CDSPCLs all increased with the increasing of the molecular weight, and were lower than that of the linear poly(ε‐caprolactone). As for CDSPCL‐b‐PEGs, the Tc and Tm of the PCL blocks were significantly influenced by the PEG segments in the copolymers. Moreover, these amphiphilic star block copolymers could self‐assemble into spherical micelles with the particle size ranging from 10 to 40 nm. Their micellization behaviors were characterized by dynamic light scattering and transmission electron microscopy. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6455–6465, 2008 相似文献
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Moged A. Berghot Nayef S. Almuaikel 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1907-1922
Synthesis of 2-anilino-1,4-napthoquinone-3-sulphonyl chloride (2) was achieved from the reaction of the title compound with chlorosulphonic acid. The interesting derivative 2 was used as a building block for synthesis of the sulphonyl derivatives 3–24. All these sulphonyl derivatives were characterized by the physical and spectral data (IR, Mass, 1H- and 13C NMR spectra). 相似文献