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991.
采用水热方法,用醚氧桥联的三羧酸配体(H3dpna)和四羧酸配体(H4deta)为主配体,2,2''-联吡啶(2,2''-bipy)和菲咯啉(phen)为辅助配体,分别与CuCl2·H2O、ZnCl2和MnCl2·4H2O反应,合成了2个二维配位聚合物{[Cu3(μ4-dpna)2(2,2''-bipy)2]·4H2O}n(1)和{[Zn3(μ4-dpna)2(2,2''-bipy)2(H2O)2]·6H2O}n(2)以及2个一维配位聚合物{[M2(μ4-deta)(phen)2(H2O)]·3H2O}n(M=Mn(3),Zn(4)),并对其结构、荧光和光催化性质进行了研究。结构分析结果表明配合物1和2属于单斜晶系,P21/c和C2/c空间群。由于采用了不同的金属离子,配合物1和2呈现不同的二维层结构。配合物3和4为异质同心结构,均属于单斜晶系,P21/n空间群。配合物3和4都具有一维链结构。另外,研究了这些配合物的荧光和对有机染料亚甲基蓝的光催化降解性能,结果表明配合物2和4可以高效地降解亚甲基蓝。 相似文献
992.
以对苯二胺和对苯二甲醛为原料缩合制备出对苯二胺缩对苯二甲醛席夫碱聚合物(PT),研究了采用不同物质的量之比的单体所制备的聚合物的电化学性能。利用席夫碱聚合物中N原子上的孤对电子与不同金属离子配位形成席夫碱配位聚合物(PT-M),并对所形成聚合物的电化学性能进行了研究。采用X射线衍射(XRD)、红外(IR)、热重-差示扫描量热法(TG-DSC)、扫描电子显微镜(SEM)和能谱(EDS)对产物进行了表征,PT-M的XRD峰强度相比于PT明显降低,表明金属离子配位进入分子链骨架中引起的空间位阻减少了分子链排列的有序性。采用循环伏安、恒电流充放电和交流阻抗评价了所制备的配位聚合物材料的电化学性能。研究发现,聚席夫碱铝配合物(PT-Al)表现出较优的电化学性能,在0.5 A·g-1的电流密度下其电容值为649.6 F·g-1,并且具有较好的循环稳定性,在8 A·g-1的电流密度下循环1 000次后仍有80.9%的电容保持率。 相似文献
993.
Baoxin Zhang Haijuan Zhang Miao Zhong Song Wang Qianhe Xu Dong-Hyung Cho Hongdeng Qiu 《中国化学快报》2020,31(1):133-135
Cysteine(Cys)plays a pivotal role in many physiological and pathological processes,including detoxification and protein synthesis.The abnormal levels of Cys are linked to many diseases.In this study,a novel red-emitting off-on fluorescent probe Cys-TCF was masterly constructed for discriminative detection of Cys.After a series of experimental assessment,Cys-TCF displayed higher selectivity and sensitivity for Cys over other biothilols with a low detection limit(0.04μmol/L).More notably,the probe was also successfully applied to image Cys in live cells and live zebrafishes with low cytotoxicity. 相似文献
994.
《中国化学快报》2020,31(11):2960-2964
Three fluorescent BINOL-Si complexes (FS1, FS2 and FS3) were rationally designed and synthesized to detect diethyl chlorophosphate (DCP), a mimic of lethal nerve agents. These three fluorescent probes showed green, yellow and orange fluorescence, respectively. Moreover, the series of fluorescent probes has the characteristics of fast response time (≤ 4 s), low detection limit (0.0097 μmol/L), high sensitivity and naked eye detection. More important, a fiber optic sensor capable of detecting DCP vapor in real time was also prepared for the first time, the lowest detection limits (down to 4.4 ppb) were all lower than that of the IDLH (immediately dangerous to life or health) concentration of Sarin (7.0 ppb). 相似文献
995.
设计了一个综合性实验,将荧光稀土液晶高分子防伪膜的制备和现代分析测试技术应用于高分子专业的教学实验中,以提高学生的综合实践能力。实验包括荧光稀土液晶高分子的制备、表征、防伪性能评价3大部分。采用FTIR、荧光光谱仪、POM、XRD、TG表征荧光稀土液晶高分子的结构与性能;制备荧光稀土液晶高分子防伪膜对其防伪性能进行评价,给整个实验增添趣味性与实用性。通过开设该实验,可让学生了解功能高分子的前沿知识及现代分析测试技术的基本原理和用途,掌握专业的实验操作与数据处理方法,提高学生的综合实践能力和专业素质。学生实验证明该综合实验适用于本科实验教学。 相似文献
996.
Two novel rhodamine-based polystyrene solid-phase fluorescence sensors PS-PA-I and PS-PA-II with different lengths of polyamines were synthesized for Hg(II) determination. The detection mechanism involving the Hg(II) chelation-induced spirocycle open of rhodamine was proposed with the aid of theoretical calculation. The stronger N-Hg bond and the longer polyamine chain in PS-PA-II led to a better selectivity, much higher and more quickly fluorescence response to Hg(II). 相似文献
997.
998.
N. Neibolts O. Platnieks S. Gaidukovs A. Barkane V.K. Thakur I. Filipova G. Mihai Z. Zelca K. Yamaguchi M. Enachescu 《Materials Today Chemistry》2020
Sustainable materials have slowly overtaken the nanofiber research field while the tailoring of their properties and the upscaling for industrial production are some of the major challenges. We report preparation of nanofibers that are bio-based and biodegradable prepared from poly (butylene succinate) (PBS) with the incorporation of nanofibrillated cellulose (NFC) and graphene nanoplatelets (GN). NFC and GN were combined as hybrid filler, which led to the improved morphological structure for electrospun nanofibers. A needleless approach was used for solution electrospinning fabrication of nanofiber mesh structures to promote application scalability. The polymer crystallization process was examined by differential scanning calorimetry (DSC), the thermal stability was evaluated by thermal gravimetric analysis (TGA), while the extensive investigation of the nanofibers structure was carried out with scanning electron microscopy (SEM) and atomic force microscopy (AFM). NFC and GN loadings were 0.5 and 1.0 wt %; while poly (ethylene glycol) (PEG) was employed as a compatibilizer to enhance fillers’ interaction within the polymer matrix. The interactions in the interface of the fillers and matrix components were studied by FTIR and Raman spectroscopies. The hybrid filler approach proved to be most suitable for consistent and high-quality nanofiber production. The obtained dense mesh-based structures could have foreseeable potential application in biomedical field like scaffolds for the tissue and bone recovery, while other applications could focus on filtration technologies and smart sensors. 相似文献
999.
Yuwei Gu Julia Zhao Jeremiah A. Johnson 《Angewandte Chemie (International ed. in English)》2020,59(13):5022-5049
Polymer networks, which are materials composed of many smaller components—referred to as “junctions” and “strands”—connected together via covalent or non‐covalent/supramolecular interactions, are arguably the most versatile, widely studied, broadly used, and important materials known. From the first commercial polymers through the plastics revolution of the 20th century to today, there are almost no aspects of modern life that are not impacted by polymer networks. Nevertheless, there are still many challenges that must be addressed to enable a complete understanding of these materials and facilitate their development for emerging applications ranging from sustainability and energy harvesting/storage to tissue engineering and additive manufacturing. Here, we provide a unifying overview of the fundamentals of polymer network synthesis, structure, and properties, tying together recent trends in the field that are not always associated with classical polymer networks, such as the advent of crystalline “framework” materials. We also highlight recent advances in using molecular design and control of topology to showcase how a deep understanding of structure–property relationships can lead to advanced networks with exceptional properties. 相似文献
1000.
Sharafudheen Pottanam Chali Bart Jan Ravoo 《Angewandte Chemie (International ed. in English)》2020,59(8):2962-2972
Carriers for intracellular delivery are required to overcome limitations of therapeutic agents such as low specificity, systemic toxicity, high clearance rate, and low therapeutic index. Nanocontainers comprised of an aqueous core and a polymer shell have received increasing attention because they readily combine stimuli response to improve intracellular payload release and surface modification to enhance selectivity towards the desired region of action. This Minireview summarizes the design and properties of polymer nanocontainers for intracellular delivery, classified according to the polymer architecture. 相似文献