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

Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p6mm) silica-block copolymer mesophases. Calcination at 500°C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35° to 80°C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140°C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.

Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores

Problems associated with large-scale pattern growth of graphene constitute one of the main obstacles to using this material in device applications. Recently, macroscopic-scale graphene films were prepared by two-dimensional assembly of graphene sheets chemically derived from graphite crystals and graphene oxides. However, the sheet resistance of these films was found to be much larger than theoretically expected values. Here we report the direct synthesis of large-scale graphene films using chemical vapour deposition on thin nickel layers, and present two different methods of patterning the films and transferring them to arbitrary substrates. The transferred graphene films show very low sheet resistance of approximately 280 Omega per square, with approximately 80 per cent optical transparency. At low temperatures, the monolayers transferred to silicon dioxide substrates show electron mobility greater than 3,700 cm(2) V(-1) s(-1) and exhibit the half-integer quantum Hall effect, implying that the quality of graphene grown by chemical vapour deposition is as high as mechanically cleaved graphene. Employing the outstanding mechanical properties of graphene, we also demonstrate the macroscopic use of these highly conducting and transparent electrodes in flexible, stretchable, foldable electronics.

Large-scale pattern growth of graphene films for stretchable transparent electrodes

The carrier collection efficiency (ηc) and energy conversion efficiency (ηe) of polymer photovoltaic cells were improved by blending of the semiconducting polymer with C60 or its functionalized derivatives. Composite films of poly(2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) and fullerenes exhibit ηc of about 29 percent of electrons per photon and ηe of about 2.9 percent, efficiencies that are better by more than two orders of magnitude than those that have been achieved with devices made with pure MEH-PPV. The efficient charge separation results from photoinduced electron transfer from the MEH-PPV (as donor) to C60 (as acceptor); the high collection efficiency results from a bicontinuous network of internal donor-acceptor heterojunctions.

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Polymer photovoltaic cells : enhanced efficiencies via a network of internal donor-acceptor heterojunctions

Vorrichtung zum Synthetisieren von Alkoholen und Ethern aus Alkanen

CdSe/CdS core/shell quantum dots have been synthesized and assembled onto prefunctionalized gold surfaces by either hydrogen bonding or covalent bonds through different functional groups. Control of the conditions during the deposition process allows producing a high coverage of quantum dots via molecular linkages. The quantum-dot surface is highly photoactive and is used in a surface sensitized Schottky barrier photovoltaic structure as the photoreception component. Atomic force microscopy (AFM) and X-ray photoelectron Spectroscopy (XPS) are used to characterize and confirm the morphology and linkage of the assemblies on Au surfaces. The electron transfer from the quantum-dot layer to the Schottky barrier device is examined by measuring the current-voltage (IV) curve of such photovoltaic devices under simulated sun light.

Assembly of CdSe/CdS Quantum Dots on Au Surfaces for Photoreception

The construction of heterostructures with engineered phases and interfaces is crucial to essentially reform the oxygen evolution reaction (OER) in water splitting. Herein, a fine ion exchange route combined subsequent...

Phase and interface co-engineered MoPxSy@NiFePxSy@NPS-C hierarchical heterostructure for sustainable oxygen evolution reaction

The acid-catalyzed synthesis of highly ordered mesostructured materials has led to a variety of twoand three-dimensional periodic symmetries, and has proven to be an effective route for the generation of fibers, spheres, thin films, and other monolithic forms of mesoporous materials. Zhao et al. recently used non-ionic poly(alkylene oxide) block copolymers, under acidic conditions, to prepare well-ordered, hexagonal mesoporous silica, denoted SBA-15, featuring uniform and adjustable large pore sizes combined with thick hydrothermally stable walls. The catalytic effect of fluoride in the synthesis of mesoporous silica at neutral to basic pH has been described by Voegtlin et al. Fluoride has been successfully used to extend the pH range over which anionic silica precursors can be utilized to create organized periodic structures; it has been used to diminish framework defects in zeolites, and to improve the organization in MCM-41 molecular sieves and MSU-X materials. However, to the best of our knowledge, no studies have been reported on the role of fluoride on cationic silica species in the aqueous acid-synthesis of ordered porous silica. In this communication, we describe the hierarchical ordering effects induced by small amounts of fluoride added during the synthesis of SBA-15-type mesoporous silica under acidic aqueous conditions. The non-ionic poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymer EO20PO70EO20 (Pluronic P123) has been employed as the structure-directing agent. At low pH, remarkably well-ordered, hydrothermally stable, large hexagonal mesoporous silica rods with uniform channels extending over micrometer-sized length scales, and with few defects, have been synthesized. The fluoride-induced enhancement of order has enabled the preparation of SBA-15 materials at moderate acidity (~ pH 2.5±3) without compromising the long-range hexagonal symmetry. The mesoporous silicas possess narrow pore-size distributions, hydrothermally stable frameworks, large surface areas, and pore volumes of up to 0.92 cm/g. This work has been motivated by our interest in i) the patterning of mesoporous materials ranging from mesoscopic to macroscopic length scales while retaining molecular-level structural control and ii) understanding the underlying mechanism for the acid-catalyzed mesoporous silica synthesis. Addition of small amounts of fluoride (F:Si molar ratios of 0.008 and 0.03; fluoride source: NH4F or (NH4)2SiF6) during the aqueous acidic SBA-15-type silica synthesis induces substantial ordering that is manifested on different length scales: both the mesoscopic structure and the macroscopic morphology of the mesoporous silicas are significantly improved. Scanning electron microscopy (SEM) has revealed that small amounts of fluoride bring about the formation of large mesoporous silica rods (Fig. 1a) when pre-

Galen D. Stucky

Papers

Vorrichtung zum Synthetisieren von Alkoholen und Ethern aus Alkanen

Assembly of CdSe/CdS Quantum Dots on Au Surfaces for Photoreception

Phase and interface co-engineered MoPxSy@NiFePxSy@NPS-C hierarchical heterostructure for sustainable oxygen evolution reaction

Fluoride‐Induced Hierarchical Ordering of Mesoporous Silica in Aqueous Acid‐Syntheses.

Trichlorobis(trimethylamine)vanadium(III)