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

Crystalline metal-organic frameworks (MOFs) are formed by reticular synthesis, which creates strong bonds between inorganic and organic units. Careful selection of MOF constituents can yield crystals of ultrahigh porosity and high thermal and chemical stability. These characteristics allow the interior of MOFs to be chemically altered for use in gas separation, gas storage, and catalysis, among other applications. The precision commonly exercised in their chemical modification and the ability to expand their metrics without changing the underlying topology have not been achieved with other solids. MOFs whose chemical composition and shape of building units can be multiply varied within a particular structure already exist and may lead to materials that offer a synergistic combination of properties.

The Chemistry and Applications of Metal-Organic Frameworks

Mobility — the transport of people and goods — is a socioeconomic reality that will surely increase in the coming years. It should be safe, economic and reasonably clean. Little energy needs to be expended to overcome potential energy changes, but a great deal is lost through friction (for cars about 10 kWh per 100 km) and low-efficiency energy conversion. Vehicles can be run either by connecting them to a continuous supply of energy or by storing energy on board. Hydrogen would be ideal as a synthetic fuel because it is lightweight, highly abundant and its oxidation product (water) is environmentally benign, but storage remains a problem. Here we present recent developments in the search for innovative materials with high hydrogen-storage capacity.

/pdf/hydrogen-storage-materials-for-mobile-applications-2dxdlm86hm.pdf

Hydrogen-storage materials for mobile applications

This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).

/pdf/cellulose-nanomaterials-review-structure-properties-and-2z8x922p3v.pdf

Cellulose nanomaterials review: structure, properties and nanocomposites

[Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming] Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China.;Cheng, HM (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, 72 Wenhua Rd, Shenyang 110016, Peoples R China;cheng@imr.ac.cn

Advanced Materials for Energy Storage

We are developing a novel concentrating solar electricity-generating technology that is both modular and dispatchable. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) uses concentrated solar flux to generate high-temperature thermal energy, which directly converts to electricity via thermoelectric generators (TEGs), stored within a phase-change material (PCM) for electricity generation at a later time, or both allowing for simultaneous charging of the PCM and electricity generation. STEALS has inherent features that drive its cost-competitive scale to be much smaller than current commercial concentrating solar power (CSP) plants. Most obvious is modularity of the solid-state TEG, which favors smaller scales in the kilowatt range as compared to CSP steam turbines, which are minimally 50 MWe for commercial power plants. Here, we present techno-economic and market analyses that show STEALS can be a cost-effective electricity-generating technology with particular appeal to small-scale microgrid applications. We evaluated levelized cost of energy (LCOE) for STEALS and for a comparable photovoltaic (PV) system with battery storage. For STEALS, we estimated capital costs and the LCOE as functions of the type of PCM including the use of recycled aluminum alloys, and evaluated the cost tradeoffs between plasma spray coatings and solution-based boron coatings that are applied to the wetted surfaces of the PCM subsystem. We developed a probabilistic cost model that accounts for uncertainties in the cost and performance inputs to the LCOE estimation. Our probabilistic model estimated LCOE for a 100-kWe STEALS system that had 5 hours of thermal storage and 8–10 hours of total daily power generation. For these cases, the solar multiple for the heliostat field varied between 1.12 and 1.5. We identified microgrids as a likely market for the STEALS system. We characterized microgrid markets in terms of nominal power, dispatchability, geographic location, and customer type, and specified additional features for STEALS that are needed to meet the needs of this growing power market.

/pdf/solar-thermoelectricity-via-advanced-latent-heat-storage-a-3apdi4mwy1.pdf

Solar thermoelectricity via advanced latent heat storage: A cost-effective small-scale CSP application

Beta-gallium oxide (β-Ga2O3) is an ultrawide bandgap semiconductor that has potential for power electronic applications and devices operating at high temperatures. Particularly important for these applications are its 4.9 eV bandgap, facile electron doping, and the ability to grow β-Ga2O3 crystals from the melt. In this work, vertical β-Ga2O3 Schottky barrier diodes were fabricated using Pt Schottky and Ti-based Ohmic contacts and Au contact pads on unintentionally doped n-type, ( 2 ¯ 01)-oriented single crystal substrates. The diode’s temperature-dependent electrical properties up to 400 °C were investigated, and the Pt/Ga2O3 Schottky barrier height was determined to be close to 1.2 eV. The degradation of the contacts over multiple cycles up to 400 °C was observed, resulting in a significant increase in series resistance of the diodes by 1000× at ambient temperature after they were cycled. According to electron microscopy measurements, this degradation is likely due in part to the migration and oxidation of Ti at the top surface of the Au contact pads. This degradation highlights the need for further research and development to ensure stable Ohmic and Schottky contacts to Ga2O3 at temperatures above 400 °C.

Performance and reliability of β-Ga2O3 Schottky barrier diodes at high temperature

Biaxially textured CeO2/YSZ/CeO2 and SrTiO3 buffer layers have been grown by pulsed laser deposition (PLD) on rolling assisted biaxially textured substrates (RABiTS) made of Ni. Full width at half maximum (FWHM) of the ω scan, scan of these buffer layers were comparable to the Ni substrates indicating good epitaxial growth on RABiTS. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements showed that these buffer layers were smooth and crack-free. CeO2/YSZ/CeO2/Ni and SrTiO3/Ni buffer layers prepared by this technique can be used as templates for the growth of high-Tc superconductors coated conductors. Unlike CeO2 seed layers, which could be easily epitaxially grown on RABiTS Ni substrates in forming gas, cube-on-cube epitaxial growth of SrTiO3 on RABiTS Ni substrates can be achieved only in a narrow window of deposition temperatures and forming gas pressure.

https://www.bc.edu/content/dam/files/schools/cas_sites/physics/pdf/Ren/p139.pdf

Growth of Biaxially Textured CeO2/YSZ/CeO2 and SrTiO3 Buffer Layers on Textured Ni Substrates by Pulsed Laser Deposition

Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction

In this letter we demonstrate a synthetic route to thick (5–20 μm) highly c‐axis textured, nearly phase‐pure superconducting (Tl,Pb)(Ba,Sr)2Ca2Cu3O9/Ag0.37 tapes. First, a Tl‐free ink consisting of Pb0.5Ba0.4Sr1.6Ca2.0Cu3.0O9/Ag0.37 precursor powder in an ethanolic ethyl cellulose binder is sprayed onto a heated LaAlO3 substrate. After an intermediate oxygen anneal to remove the carbonaceous binder, a static 2‐zone thallination anneal is performed to promote superconducting phase formation. Films exhibit excellent c‐axis texturing as evidenced by x‐ray diffraction θ/2θ and rocking curve characterization with morphological evidence for partial melting by scanning electron microscopy. Electrical characterization of these films give Tc onset values of 106–115 K with Tc zero reached by 99–101 K and transport Jc(77 K) up to 2.9×104 A/cm2. A mixed strong/weak‐linked magnetic field dependence is observed for these films at 77 K and 0.4 T.

Philip A. Parilla

Papers

Solar thermoelectricity via advanced latent heat storage: A cost-effective small-scale CSP application

Performance and reliability of β-Ga2O3 Schottky barrier diodes at high temperature

Growth of Biaxially Textured CeO2/YSZ/CeO2 and SrTiO3 Buffer Layers on Textured Ni Substrates by Pulsed Laser Deposition

Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction

Thick c‐axis textured (Tl,Pb)(Ba,Sr)2Ca2Cu3O9/Ag0.37 superconducting tapes by an ink spray pyrolysis method using a Tl‐free precursor