다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Research in the use of organic polymers as the active semiconductors in light-emitting diodes has advanced rapidly, and prototype devices now meet realistic specifications for applications. These achievements have provided insight into many aspects of the background science, from design and synthesis of materials, through materials fabrication issues, to the semiconductor physics of these polymers.

Electroluminescence in conjugated polymers

As a fascinating conjugated polymer, graphitic carbon nitride (g-C3N4) has become a new research hotspot and drawn broad interdisciplinary attention as a metal-free and visible-light-responsive photocatalyst in the arena of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability, and “earth-abundant” nature. This critical review summarizes a panorama of the latest progress related to the design and construction of pristine g-C3N4 and g-C3N4-based nanocomposites, including (1) nanoarchitecture design of bare g-C3N4, such as hard and soft templating approaches, supramolecular preorganization assembly, exfoliation, and template-free synthesis routes, (2) functionalization of g-C3N4 at an atomic level (elemental doping) and molecular level (copolymerization), and (3) modification of g-C3N4 with well-matched energy levels of another semiconductor or a metal as a cocatalyst to form heterojunction nanostructures. The constructi...

Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?

Fossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. Polymer-based organic photovoltaic systems hold the promise for a cost-effective, lightweight solar energy conversion platform, which could benefit from simple solution processing of the active layer. The function of such excitonic solar cells is based on photoinduced electron transfer from a donor to an acceptor. Fullerenes have become the ubiquitous acceptors because of their high electron affinity and ability to transport charge effectively. The most effective solar cells have been made from bicontinuous polymer–fullerene composites, or so-called bulk heterojunctions. The best solar cells currently achieve an efficiency of about 5 %, thus significant advances in the fundamental understanding of the complex interplay between the active layer morphology and electronic properties are required if this technology is to find viable application.

Polymer–Fullerene Composite Solar Cells

Macromol. Chem. Phys. 4/2013

Interfacial Design through Poly-Ionic Liquid Surface Modification in Efficient pin Perovskite Solar cells

The spectral characteristics of polyfluorene (PF) based light-emitting diodes (LEDs) are discussed. First, conditions that facilitate photo-oxidation of PF are investigated. We show that dense chain packing and addition of hole-trapping moieties lead to increased defect formation. Second, devices containing either a defined low concentration of keto-defects or of the polymer poly(9,9-octylfluorene-co-benzothiadiazole) (F8BT) are presented. Both types of blend layers were tested in different device configurations with respect to the relative and absolute intensities of green and blue emission components. It is shown that either blending of hole-transporting molecules into the emission layer at low concentration or the incorporation of a suitable hole-transporting layer reduces the green emission in the PF:F8BT blend, similar to what is observed for the keto-containing PF layer. We conclude that photo-oxidation leads to the formation of keto-defects that mainly constitute weakly-emissive electron traps.

Fluorenone defects in polyfluorene-based light-emitting diodes: emission properties and device performance

Two series of novel random polyfluorene copolymers containing quinoxaline units were prepared by stressing the coupling according to Yamamoto. The first series contains 2,3-bis-(4'-tert-butyl-biphenyl-4-yl)benzo[g]quinoxaline and the second series 2,3-bis-(4'-tert-butyl-biphenyl-4-yl)quinoxaline as energy accepting unit. The copolymers were identified by gel permeation chromatography, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. Thermal properties were analyzed by thermal gravimetric analysis and differential scanning calorimetry revealing amorphous copolymers that are stable up to 430 °C. The morphology was investigated using atomic force microscopy. The optical properties in solutions and thin films were analyzed. Furthermore, the thin film electro-optical properties were determined in monolayer polymer light-emitting devices. Single layer devices were built with efficiencies ranging from 0.15 to 2.0 cd/A. For the random copolymers with 5 mol % benzo[g]quinoxazoline in the polyfluorene backbone some threefold efficiency enhancement from 1.1 to 3.0 cd/A was achieved by utilizing an ultra thin interlayer of poly(9,9-di-n-octylfluorene-2,7-diyl)-alt-[1,4-phenylene-(4-sec-butylphenylimino)-1,4-phenylene] between PEDOT:PSS and the emissive random copolymer layer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4773-4785, 2007

Random fluorene copolymers with on-chain quinoxaline acceptor units Part A Polymer chemistry

The electromechanical properties of ultrathin films of polyglutamates with either a preferential polar upright orientation of the helical chains or an orientation parallel to the substrate plane are compared. The electric field- induced change in film thickness as determined by an electromechanical interferometer is used to measure of the degree of polar order and the mechanical compliance. Following the approach by Whitesell and Chang monomolecular films of 15 nanometer thickness of the helical polypeptide poly((gamma) -benzyl-L-glutamate) (PBLG) were grown directly from a flat aluminum surface. The measured PBLG film polarization was found to be comparable to that of conventional ferroelectric materials. This result demonstrates that the polymerization starting from the surface forces the helical chains into a polar arrangement. A large mechanical plate modulus of the film of approximately 35 GPa as determined by electrostriction agreed with the theoretical prediction for a single PBLG molecule along the chain axis.In contrast to this, Langmuir- Blodgett layers of poly((gamma) -octadecyl-co-methyl-L- glutamate)s, bearing long flexible side chains, exhibited only negligible piezoelectric activities, as the helices are oriented parallel to the substrate surface.In this case the mechanical properties were almost entirely determined by the structure and packing of the flexible side chains.

Dieter Neher

Papers

Macromol. Chem. Phys. 4/2013

Interfacial Design through Poly-Ionic Liquid Surface Modification in Efficient pin Perovskite Solar cells

Fluorenone defects in polyfluorene-based light-emitting diodes: emission properties and device performance

Random fluorene copolymers with on-chain quinoxaline acceptor units Part A Polymer chemistry

Electromechanical properties of anisotrope ultrathin layers of polyglutamates