仿生制备功能性聚合物光子晶体

简述了自然界生物光子晶体经过不断的进化与演变而具有的一些特殊的性能,如亮丽的结构色彩、特殊的浸润性及高强度.受自然界生物光子晶体的这些特殊性能启发,通过对聚合物乳胶粒硬核软壳结构、表面功能基团及表面形貌的设计和调控等方法仿生制备了具有特殊浸润性的光子晶体;并在胶体晶体的聚合物乳胶粒间引入光交联聚合物,制备得到高强度的光子晶体;通过对蘑菇头形状乳胶粒两端的浸润性差异的设计制备,组装得到新型的各向异性结构的光子晶体.进一步发展了这些功能性光子晶体在湿度检测、油传感、自振荡体系等方面的应用.发展了通过喷涂、打印方法实现大面积、图案化聚合物光子晶体的简单制备.     

功能型聚合物光子晶体的制备及应用

光子晶体因其特殊的光调控性能,在各类高性能光学器件方面具有重要的应用前景.本文主要阐述了功能型聚合物光子晶体的制备方法及其在防护涂层、高效发光、高灵敏检测和高性能光信息存储等方面的应用.     

生物结构刺激响应光子晶体的研究进展

自然物种演化形成了多种复杂而精细的光子结构,这类结构兼具功能的特点,将具有刺激响应特性的材料与天然生物光子结构相结合,能够制备得到响应性光子晶体材料,在生物医疗检测、传感器件、装饰和防伪等方面具有巨大的应用前景.本文在前期研究工作的基础上,综述了近年来,具有生物结构的响应性光子晶体的研究进展,总结了自然界的天然分级光子结构种类及显色机理,重点阐述了基于刺激响应聚合物的响应性光子晶体的构筑及应用、以及响应机理,最后对具有生物结构的响应性光子晶体材料的问题进行了总结,对未来的研究进行了展望.     

光子晶体的制备及应用

光子晶体（PC）是具有光子带隙的周期性电介质结构，频率落在光子带隙中的光将被禁止传播。本文对光子晶体的能带结构、带隙的产生、制备方法及应用作了简要的介绍，重点介绍了光子晶体的制备技术及其在光电领域中的应用前景。     

胶体光子晶体膜的超浸润性研究进展

近年来,由于具有特殊浸润性的胶体光子晶体膜在传感、检测、催化等方面的重要应用,胶体光子晶体膜的超浸润研究受到科研工作者的广泛关注.本文阐述了包括超亲液、超疏液、两亲性、梯度浸润性、可调控浸润性、图案浸润性等具有特殊浸润性光子晶体膜的制备及其相关应用,并讨论疏水、超疏水和亲-疏图案不同浸润性基底对所制备胶体光子晶体膜的功能性及其相关应用的影响.该工作对于发展新型功能型材料器件的制备具有重要的借鉴及指导意义.     

胶体晶体微球及其生物医学应用

光子晶体(PhCs)是由单分散纳米粒子周期性排列形成的材料,具有光子禁带,频率落在光子禁带内的光被禁止传播,这个特性激起了研究者对其制备和应用的研究热情。然而,一般的光子晶体材料都具有角度有偏性质,限制了其在宽视角光学材料和设备上的应用。近几年有一系列围绕球形胶体光子晶体材料的研究成果问世,由于球形的对称性,球形胶体晶体的衍射峰不会随着光的入射角变化而发生变化,从而拓宽了胶体晶体的应用范围。随着微流控技术被用于制备液滴模板,球形胶体晶体的制备取得了巨大的进步。微流控技术不仅保证了液滴模板的单分散性,还增加了胶体晶体微球的结构与功能的多样性。胶体晶体微球这些特有的性质,可以很好地将光子晶体材料与编码、非标记检测、细胞培养以及载药等生物医学领域连接起来,为其应用提供了广阔的前景。本文总结了球形光子晶体的研究进展,包括球形光子晶体的设计、制备及其生物医学应用,最后,对球形光子晶体未来的发展方向作了展望。     

二维光子晶体

光子晶体是一种介电常数周期变化的功能材料,其基本特征是具有光子带隙。光子晶体理论诞生已三十年,基于理论及实验的研究取得了许多成绩。当所制备的光子带隙与光波的波长相当时,光子晶体材料抑制光子在一定频段内的传播。由于在光学、电学、热学、磁学等方面均有优良特性和潜在应用,光子晶体作为一种新型材料也越来越受到科研人员的青睐。不论在可加工性方面还是在传播特性方面,二维光子晶体的优势正逐渐体现出来。本文重点阐述二维光子晶体的研究进展,分别介绍了二维光子晶体的结构与性能特点以及近年来发展出的新型制备方法,如自组装法、刻蚀法、多光束干涉法等,并着重列举其在传感器、波导、光纤、太赫兹技术等领域的发展现状,表明二维光子晶体作为超材料具有巨大的发展空间和潜力。最后,本文对二维光子晶体今后的研究方向和发展前景作了展望。     

快速响应聚合物光子晶体研究进展

响应性光子晶体以其亮丽的结构色彩及光学信号对外场刺激的响应性变化,在化学传感、智能显示等领域具有重要的应用前景.本文综述了快速响应聚合物光子晶体的研究进展.首先从原理上阐述了影响溶胀型光子晶体响应速率的因素,系统总结了针对不同因素提高其响应速率的研究工作,着重探讨了溶胀型光子晶体水凝胶的尺寸、聚合物链段的物理化学性能(包括多孔结构和亲疏水性)、凝胶网络的交联度等因素对响应速率的影响.同时也简要介绍了影响非溶胀型响应性光子晶体,如光、电、磁、机械力等外场诱导体系折光指数变化的响应性光子晶体的响应速率的因素.最后展望了响应性光子晶体的热点研究方向.这些工作对于提高光子晶体的响应速率,发展其在实时分析、在线检测等领域的应用具有重要意义.     

聚苯乙烯光子晶体薄膜的光化学行为

研究了紫外光照下聚苯乙烯（PS）光子晶体薄膜的表面形貌、光学性质及浸润性变化. 傅立叶红外光谱对紫外光照前后薄膜表面的化学成分进行了表征,结果表明紫外光照后PS微球表面产生亲水性极性基团羰基. 扫描电子显微镜照片表明随着紫外光照时间的延长,PS微球发生收缩、变形甚至熔化. 原位反射和透射光谱表明在光照20 min内,光子晶体薄膜能够保持良好的光学性能,且薄膜由疏水表面转变为亲水表面. 因此,控制光照时间可以制备得到具有良好光学性能的亲水性聚合物光子晶体薄膜,对于光子晶体在特殊环境下的应用具有重要的意义.     

光子晶体应用于化学及生物传感器的研究进展

光子晶体是由两种以上具有不同折光指数的材料在空间按照一定的周期顺序排列所形成的有序结构材料,它具有尺度为光波长量级的重复结构单元,通过对这些结构单元的合理设计.可以调控光子晶体的光学性质.近年来,光子晶体不仅在药物释放、光学开关、金属探针领域取得了广泛的应用,也为化学及生物传感器领域提供了新的检测原理和手段.本文概述了光子晶体的制备方法及近年来该技术在化学及生物传感器领域中的应用研究.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.