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We report the catalyst-free synthesis of the arrays ofcore–shell,ultrathin, size-uniform SiC/AlSiC nanowires on the top of a periodicanodic aluminum oxide template. The nanowires were grown using anenvironmentally friendly, silane-free process by exposing the siliconsupported porous alumina template to CH4 H2plasmas. High-resolution scanning and transmission electron microscopystudies revealed that the nanowires have a single-crystalline corewith a diameter of about 10 nm and a thin (1–2 nm) amorphousAlSiC shell. Because of their remarkable length, high aspect ratio,and very high surface area-to-volume ratio, these unique structuresare promising for nanoelectronic and nanophotonic applications thatrequire efficient electron emission, light scattering, etc. A mechanismfor nanowire growth is proposed based upon the reduction of the aluminatemplate to nanosized metallic aluminum droplets forming between nanopores.The subsequent incorporation of silicon and carbon atoms from theplasma leads to nucleation and growth from the top of the aluminatemplate. [ABSTRACT FROM AUTHOR]

We estimate the domestic environmental and health benefits of exploiting China's energy-related CDM potential. Exploiting the CDM potential may save between 3,000 and 40,000 lives annually. Additional gains are estimated to reach upwards from 1 billion RMB annually. The key to these gains is the fact that actions and measures to reduce CO2 emissions also reduce emissions of TSP and SO2. In our estimate, exploiting the CDM-potential will cut SO2-emissions by between one-half and three million tons annually. To arrive at these conclusions we synthesize a significant body of recent research on co-benefits of climate abatement in China. [ABSTRACT FROM AUTHOR]

An industrial boiler-efficiency improvement program (IBEI) that focuses on simple, inexpensive measures to improve the operating efficiency of coal-fired industrial boilers in Shanxi, China, is presented. The potential mitigation of CO2 emissions and its cost, based on this program, are calculated together with estimates of health benefits associated with the reduction of air pollution. The results show that, if the average efficiency of industrial boilers were improved from 60 to 70%, 3 million tons of coal could be saved, and CO2 emissions be reduced by 5 million tons annually at a cost of less than US$2 per ton of CO2. The health benefits are valued at about US$86 million per year, including the avoidance of about 700 premature deaths annually. The proposed IBEI program would, therefore provide an ideal case by which to address the issue of global warming in China and to achieve national goals concerning the growth of the economy, and environmental protection. [Copyright &y& Elsevier]

Increasingly intricate in their composition and structural organization, hierarchical multicomponent metamaterials with nonlinear spatially reconfigurable functionalities challenge the intrinsic constraints of natural materials, revealing tremendous potential for the advancement of biochemistry, nanophotonics, and medicine. Recent breakthroughs in high-resolution nanofabrication utilizing ultranarrow, precisely controlled ion or laser beams have enabled assembly of architectures of unprecedented structural and functional complexity, yet costly, time- and energy-consuming high-resolution sequential techniques do not operate effectively at industry-required scale. Inspired by the fictional Baron Munchausen's fruitless attempt to pull himself up, it is demonstrated that metamaterials can undergo intrinsically driven self-assembly, metaphorically pulling themselves up into existence. These internal drivers hold a key to unlocking the potential of metamaterials and mapping a new direction for the large-area, cost-efficient self-organized fabrication of practical devices. A systematic exploration of these efforts is presently missing, and the driving forces governing the intrinsically driven self-assembly are yet to be fully understood. Here, recent progress in the self-organized formation and self-propelled growth of complex hierarchical multicomponent metamaterials is reviewed, with emphasis on key principles, salient features, and potential limitations of this family of approaches. Special stress is placed on self-assembly driven by plasma, current in liquid, ultrasonic, and similar highly energetic effects, which enable self-directed formation of metamaterials with unique properties and structures., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To fabricate organic-inorganic composite tissue engineering scaffolds for reconstructing calcified cartilage layer based on three-dimensional (3D) printing technique., Methods: The scaffolds were developed by 3D-printing technique with highly bioactive calcium-magnesium silicate ultrafine particles of 1%, 3% and 5% of mass fraction, in which the organic phases were composed of type I collagen and sodium hyaluronate. The 3D-printed scaffolds were then crosslinked and solidified by alginate and CaCl₂ aerosol. The pore size and distribution of inorganic phase were observed with scanning electron microscope (SEM); the mechanical properties were tested with universal material testing machine, and the porosity of scaffolds was also measured., Results: Pore size was approximately (212.3 ± 34.2) μm with a porosity of (48.3 ± 5.9)%, the compressive modulus of the scaffolds was (7.2 ± 1.2) MPa, which was irrelevant to the percentage changes of calcium-magnesium silicate, the compressive modulus was between that of cartilage and subchondral bone., Conclusion: The porous scaffolds for calcified cartilage layer have been successfully fabricated, which would be used for multi-layered composite scaffolds in osteochondral injury.