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51.
α-四(烷基苯氧基)酞菁配合物的合成与表征 总被引:5,自引:0,他引:5
以邻苯二甲酸酐为原料,经硝化、氨化、亲核取代和金属离子模扳等多步反应合成了两个系列共5个叔丁基取代苯氧基金属酞菁配合物,产物经元素分析,IR表征,测定了目标配合物的紫外可见吸收光谱、荧光光谱及在有机溶剂中的溶解性。结果发现:与无取代金属酞菁配合物相比,Q带最大吸收光谱波长红移;在710nm波激发下,目标配合物在环已烷等有机溶剂中均有荧光发射(最大发射波长在760nm左右);在二氯甲烷、氯仿、环已烷、Py、苯、甲苯、乙基环已烷、乙基溶纤剂等中溶解性能良好。 相似文献
52.
类胡萝卜素是一类奇特的色素,由高等植物和微生物光化学合成,作为防止单线氧通过光敏反应产生危害的必要基团,类胡萝卜素最近受到了关注。类胡萝卜素联于富勒烯上,既可大大增加在可见光区域光诱导电子转移的有效吸收断面,又可抑制富勒烯敏化单线氧的危害能力。合成了类胡萝卜素的相关化合物,报道的某些反应条件先进且简洁。 相似文献
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54.
Hsuan‐Ying Chen Wei‐Yi Lu Yen‐Jen Chen Sodio C. N. Hsu Siou‐Wei Ou Wei‐Te Peng Nai‐Yuan Jheng Yi‐Chun Lai Bo‐Sheng Wu Hsuan Chung Yun Chen Ta‐Chou Huang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(2):327-333
This study synthesized a series of titanium iminophenoxide complexes and investigated their suitability as catalysts for the ring‐opening polymerization of L ‐lactide (L ‐LA) and ε‐caprolactone (CL). Complexes with bidentate ligands demonstrate higher catalytic activity than their tridentate counterparts since the third coordination atom needs to contend with L ‐LA and CL. Differences in the geometric framework of bidentate ligands also influence the catalytic activity. Type II ligands (N, N‐trans form of Ti complex) prevent the coordination of monomers to Ti thereby decreasing the initiation rate. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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Xiao‐Dong Li Wei Ding Feng‐Ping Miao Nai‐Yun Ji 《Magnetic resonance in chemistry : MRC》2012,50(2):174-177
Three new halogenated chamigrane sesquiterpenes, laurokamin A (1), laurokamin B (2), and laurokamin C (3), and four known halogenated chamigrane sesquiterpenes, 10‐bromo‐α‐chamigrene (4), 10‐bromo‐β‐chamigrene (5), 2,10‐dibromo‐3‐chloro‐β‐chamigrene (6), and obtusane (7), were isolated from the marine red alga Laurencia okamurae collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously identified by one‐ and two‐dimensional NMR and mass spectroscopic methods. The antimicrobial activity of compounds 1–3 was evaluated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
57.
E. M. Woo Ya‐Ting Hsieh Wei‐Ting Chen Nai‐Tzu Kuo Lai‐Yen Wang 《Journal of Polymer Science.Polymer Physics》2010,48(11):1135-1147
Using differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and Fourier transformed infrared spectroscopy (FTIR), upper critical solution temperature (UCST) phase behavior with immiscibility–miscibility transformation in blends of poly(ethylene succinate) (PESu) with poly(lactic acid)s (PLAs), such as poly(D ,L ‐lactic acid) (PDLLA), poly(L ‐lactic acid) (PLLA), poly(D ‐lactic acid) (PDLA), differing in D/L configurations and molecular weights were investigated. All three binary blends of PDLLA/PESu, PLLA/PESu, and PESu/PDLA exhibit UCST behavior, which means they are immiscible at ambient temperature but can become miscible upon heating to higher temperatures at 240–268 °C depending on molecular weights. The PLLAs/PESu blends at UCST could be reverted back to the original phase‐separated morphology, as proven by solvent redissolution. The blends upon quenching from above UCST could be frozen into a quasi‐miscible state, where the Flory‐Huggins interaction parameter (χ12) was determined to be a negative value (by melting point depression technique). The interaction between PDLLA and PESu in blend resulted in significant reduction in spherulite growth rate of PESu. Furthermore, blends of PESu with lower molecular weight PLLA or PDLA (Mw of PLLA and PDLA are 152,000 and 124,000 g/mol, respectively), instead of the higher Mw of PDLLA (Mw of PDLLA = 157,000 g/mol), are immiscible with UCST phase behavior, which are affected by molecular weights rather than the ratio of L/D monomer in the chemical structure of PLAs. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1135–1147, 2010 相似文献
58.
Hao Gao Kui Hong Guo‐Dong Chen Chuan‐Xi Wang Jin‐Shan Tang Yang Yu Miao‐Miao Jiang Man‐Mei Li Nai‐Li Wang Xin‐Sheng Yao 《Magnetic resonance in chemistry : MRC》2010,48(1):38-43
Two new oxidized sterols 1 and 2 were obtained from the active fraction of a mangrove fungus Aspergillus awamori isolated from the soils around the mangrove plant Acrostichum speciosum. Their structures were elucidated using spectroscopic methods as 22E‐7α‐methoxy‐5α,6α‐epoxyergosta‐8(14),22‐dien‐3β‐ol (1) and 22E‐3β‐hydroxy‐5α,6α,8α,14α‐diepoxyergosta‐22‐en‐7‐one (2). The NMR data and complete assignments for both DMSO‐d6 and CDCl3 were given. Their cytotoxic activity against A549 cell line was evaluated. Furthermore, the detailed conformation analysis for ring B (cyclohexene oxide system) of sterol 1 was given on the basis of NOEs. The endo‐boat conformation was considered as the preferred conformation for ring B rather than half‐chair conformation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
The unsaturated hyperbranched polyester (UH20) based on Boltorn™ H20 (H20) end‐capped with methacrylate groups and carboxylic acid groups was introduced to treat calcium carbonate (CaCO3) as a new type of surface modifier by a wet‐coating technique. The interaction between CaCO3 and modifier was proven to be due to the ionic character by FT‐IR after the extraction with acetone. The maximum amount of tightly bonded UH20 modifier was determined to be around 9% by thermogravimetric analysis (TGA). The incorporation of CaCO3 coated with UH20 into high‐density polyethylene (HDPE) decreased the mechanical performance of HDPE/CaCO3 composite in comparison with CaCO3 coated with stearic acid. In the presence of a small amount of dicumyl peroxide (DCP), a greatly improvement of the notched impact strength as well the tensile strength of HDPE/CaCO3 coated with UH20 composite was obtained. An enhanced effect in the mechanical performance of the composite between CaCO3 coated with UH20 and HDPE matrix in the existence of DCP was suggested. Moreover, the morphological structures of impact fracture surface of the HDPE/CaCO3 composites were studied by scanning electron microscopy (SEM) to confirm the possible mechanism for explaining the improvement of mechanical properties of the composite. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
60.
New kinds of narrowly distributed protein‐based nanoparticles, bovine serum albumin‐Poly (acrylic acid) (BSA/PAA) nanospheres, and nanocapsules were prepared via in situ polymerization, swelling, and re‐aggregation. The structure and morphology of the nanospheres were characterized by UV‐Vis, FT‐IR, DLS, and TEM. The stability of the BSA/PAA nanospheres and nanocapsules was increased when their skeletons were fixed by cross‐linked agents. The nanospheres carried a positive charge and their size was about 80–110 nm. The protein‐based nanocapsules were stimuli‐responsive with pH value and their hydrodynamic diameter varied from 70 to 230 nm with changes of pH. In vitro release experiments of Rhodamine B and Doxorubicin hydrochloride showed that these biopolymer nanoparticles provided a controlled release of the entrapped drugs for 300 hr. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献