α-Hydroxy alkanones were synthesised with high enantiomeric purity by stereoselective enzyme-catalysed diketone reduction. Both diketone reduction and cofactor regeneration were accomplished with purified carbonyl reductase from Candida parapsilosis (CPCR2). The reaction products were isolated by column chromatography and analysed by chiral GC measurements, 1H-NMR spectroscopy and determination of optical rotations. Preparative-scale biotransformations yielded 350–600 mg of pure aliphatic α-hydroxy ketones including the difficult to obtain (S)-2-hydroxypentane-3-one. For all the products good enantiomeric excesses in the range of 89–93% were achieved.

by Jan C. Willems. / Bibliography: p. 11. / "August, 1981." / Supported in part by the U.S. Dept. of Energy under Contract DOE/ET-76-A-012295

Essentially, the term aerogel describes a special geometric structure of matter. It is neither limited to any material nor to any synthesis procedure. Hence, the possible variety of materials and therefore the multitude of their applications are almost unbounded. Here we present a comprehensive picture of the most promising developments in the field during the last decades.

Finally, the research sketches in more details about Lin Lingsu's background before he set his foot in Beijing; moreover, with referring to a few of compiled works of Taoist rituals, the text gives a terse but adequate description of his reformation of Taoist ritual contents. In conclusion, this thesis probes further into his status among Taoist rituals, and states that the Shenxiao Sect ritual has made a real impact on Lingbao Donghua Sect, which is closely linked with Lin Lingsu's birthplace, Wenzhou. / On the basis of consulting the related academic results and methodologies achieved by Chinese and foreign scholars, the text widely garners materials of all kinds, which include Taoist literature, history records, anthology, notes, and local history as sources in addition to the three most basic and widely-circulated versions of Lin Lingsu's biography. / The research provides several insights into some of the issues that remain debatable to this day. To start with, it reveals that back in early Northern Song Dynasty in Sichuan area there prevailed a Thunder-God register, an affiliate of Celestial Masters' talismans and registers. Also in the discovery is that in anthologies and notes, composed in the same period, in the coastal region to the south of the Yangzi River there existed the depiction of Thunder Troop which was mentioned in the Taoist Canon. All these records show that Thunder Rites not only is the outcome of a distinctive, thunder-roaring climate in the southeast coast of China, but it is also characterized as being intricate, and most importantly it has long been filed in the officially-compiled Taoist Canon. / Then, the research gives a specific and clearer outline of Shenxiao Movement. In the external aspect, it has done an even more comprehensive investigation from different angles: the symbolic meaning that the establishment of Shenxiao Temples represents, the scale and geographical distribution. Internally, the text points out that the Shenxiao teachings has an almost inseparable connection with the Taoism's three traditions, Shangqing, Lingbao and Celestial Masters, in terms of personages, scriptures and rituals etc. What's more important is that Shenxiao teachings, intrinsically, has its ordination practice, scripture and ritual, which greatly qualify the sect as a denomination of the Taoist faith. / This thesis is a case study of Lin Lingsu (1076-1120), a Wenzhou native Taoist priest in Northern Song Dynasty. The text, aimed at the course of his life as well as the religious events, in which he was later involved in Bianjing, delves into the development of Taoism in Northern Song Dynasty---Shenxiao Movement in particular, launched by him during the periods of Zhenghe (1110-1118) and Xuanhe (1119-1125), the reign of Emperor Huizong---and hence the influence as the result of it. In other words, the research builds itself on a network connecting a single personage and time lengthways with events, space and other relevant personages breadthways. Thereafter, it goes further into some issues related with Taoism in Northern Song Dynasty and reevaluates a negative perspective of Lin Lingsu seen in Song History. / 李麗涼. / 論文(哲學博士)--香港中文大學, 2006. / 參考文獻(p. 240-257). / Adviser: Chi Tim Lai. / Source: Dissertation Abstracts International, Volume: 68-02, Section: A, page: 0607. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in Chinese and English. / School code: 1307. / Lun wen (zhe xue bo shi)--Xianggang Zhong wen da xue, 2006. / Can kao wen xian (p. 240-257). / Li Liliang.

A new route to highly active hopcalite catalysts via flame spray pyrolysis of an inverse microemulsion precursor is reported. The nitrate derived nanoparticles are around 15 nm in diameter and show excellent conversion of CO under ambient conditions, outperforming commercial reference hopcalite materials produced by co-precipitation.

Molecular brushes of poly(2-oxazoline)s (POx) are an intriguing class of polymers as they combine a unique architecture with the properties of POx as a biomaterial. Here, the synthesis of several POx macromonomers with methacrylate end groups and consecutive grafting through polymerization by aqueous atom transfer radical polymerization (ATRP) at room temperature is reported. 1H-NMR spectroscopy and size exclusion chromatography (SEC) confirmed the synthesis of POx molecular brushes with maximum side chain grafting densities, narrow molar mass distributions (Đ ≤ 1.16) and final molar masses corresponding to the initial macromonomer : initiator ratio. Chain extension experiments show high end group fidelity and formation of block copolymer molecular brushes, and kinetic studies revealed a polymerization behavior of oligo(2-methyl-2-oxazoline) methacrylate very similar to the frequently used oligo(ethylene glycol) methacrylate (OEGMA475). Aqueous solutions of POx molecular brushes with poly(2-ethyl- and 2-isopropyl-2-oxazoline) side chains exhibit the typically defined thermoresponsive behavior with a tunable, very narrow and reversible phase transition

Surface engineering with polymer brushes has become one of the most versatile techniques to tailor surface properties of substrates for a broad variety of (bio-) technological applications. We report on a new facile approach to prepare defined and dense polymer brushes on planar substrates by surface-initiated Cu(0) mediated controlled radical polymerization (SI-CuCRP) of numerous vinyl monomers using a copper plate at room temperature. The fabrication of a variety of homo-, block, gradient and patterned polymer brushes as well as polymer brush arrays is demonstrated. The SI-CuCRP was found to be strictly surface-confined, of highly living character, proceeds remarkably fast and results in polymer brushes of very high grafting densities. The brush layer thickness can be modulated by the polymerization time or by the distance of the copper plate to the modified substrate. As the copper plate can be reused multiple times, no additional copper salts are added and only minimal amount of chemicals is needed, the simple and low-cost experimental conditions allows researchers from various fields to prepare tailored polymer brush surfaces for their needs.

Non-ordered porous networks, so-called aerogels, can be achieved by the 3D assembly of quantum dots (QDs). These materials are well suited for photonic applications, however a certain quenching of the photoluminescence (PL) intensity is observed in these structures. This PL quenching is mainly attributed to the energy transfer mechanisms that result from the close contact of the nanoparticles in the network. Here, we demonstrate the formation of a novel aerogel material with non-quenching PL behaviour by non-classical, reversible gel formation from tetrazole capped silica encapsulated QDs. Monitoring of the gelation/degelation by optical spectroscopy showed that the optical properties of the nanocrystals could be preserved in the 3D network since no spectral shifts and lifetime shortening, which can be attributed to the coupling between QDs, are observed in the gels as compared to the original colloidal solutions. In comparison with other QD-silica monoliths, QDs in our gels are homogeneously distributed with a distinct and controllable distance. In addition we show that the silica shell is porous and allows metal ions to pass through the shell and interact with the QD core causing detectable changes of the emission properties. We further show the applicability of this gelation method to other QD materials which sets the stage for facile preparation of a variety of mixed gel structures.

A class of novel nickel cobalt oxide hollow nanosponges were synthesized through a sodium borohydride reduction strategy. Due to their porous and hollow nanostructures, and synergetic effects between their components, the optimized nickel cobalt oxide nanosponges exhibited excellent catalytic activity towards oxygen evolution reaction.

Soft lithographic methods describe a set of printing methods which are widely used for the preparation of structured surfaces. Structured surfaces are essential components in the field of (opto-)electronic devices such as organic light emitting diodes, photovoltaics or organic field effect transistors. In recent years, crucial progress has been achieved in the development of patterned metal coatings for these applications. This review focusses on new strategies for soft lithographical printing of metal structures emphasizing the subtle interplay of printing techniques, metal precursor chemistry, and surface functionalization strategies. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.