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

Advanced electrochemical energy storage devices (EESDs) that can store electrical energy efficiently while being miniature/flexible/wearable/load-bearing are much needed for various applications ranging from flexible/wearable/portable electronics to lightweight electric vehicles/aerospace equipment. Carbon-based fibers hold great promise in the development of these advanced EESDs (e.g., supercapacitors and batteries) due to their being lightweight, high electrical conductivity, excellent mechanical strength, flexibility, and tunable electrochemical performance. This review summarizes the fabrication techniques of carbon-based fibers, especially carbon nanofibers, carbon-nanotube-based fibers, and graphene-based fibers, and various strategies for improving their mechanical, electrical, and electrochemical performance. The design, assembly, and potential applications of advanced EESDs from these carbon-based fibers are highlighted. Finally, the challenges and future opportunities of carbon-based fibers for advanced EESDs are discussed.

Carbon-Based Fibers for Advanced Electrochemical Energy Storage Devices

fine particle hypothesis stating that ambient ultrafine particles (UFP; < 0.1 μm in aerodynamic diameter) may cause adverse health effects at the first Colloquium for Particulate Air Pollution and Human Mortality and Morbidity in Irvine, California, it was met with friendly skepticism as well as out-right dismissal. Arguments were that UFP are very short-lived and disappear through heterogeneous and homogeneous aggregation within seconds or minutes and therefore are toxicologically irrelevant. These arguments did not recognize that UFP are continuously generated or that ambient UFP contribute very little, if any, mass to ambient PM10 (particles < 10 μm in aerodynamic diameter) or PM2.5 (particles < 2.5 μm in aerodynamic diameter). Indeed, the mass distribution of a typical urban aerosol among the different particle sizes may support this point (Figure 1). This attitude of skepticism has changed considerably. Research teams across the world are working now on UFP, forming multidisciplinary alliances between atmospheric scientists, engineers, epidemiologists, clinicians, and toxicologists. They investigate UFP sources, generation, physicochemical characteristics, behavior in ambient air, and potential effects and underlying mechanisms following their inhalation. Still, sound skepticism lingers, as demonstrated by the title of a presentation at the 2002 meeting of the Health Effects Institute: “Nanoparticles: Are They Real?” Obviously, there is no question that UFP are real, but it is also clear that we still do not know enough about them, despite significant progress in our understanding since 1994. Atmospheric UFP derived from gas-to-particle conversions have many sources, natural and anthropogenic, the latter being mostly derived from internal combustion processes. Diesel fuel, gasoline, and even compressed natural gas—considered to be “clean”—powered engines all emit high numbers of UFP. If these anthropogenic UFP cause significant health effects, is the conversion of dieselpowered buses to compressed natural gas—as practiced now in several cities—really a good idea? We should be more cautious about introducing technologies based on the assumption that they result in cleaner air with fewer and less toxic contaminants. The experience with methyl tert-butyl ether as a fuel additive should serve as a reminder of the potential unintended health and environmental consequences of altering fuels and resulting emissions on a large scale without an adequate understanding of toxicity. Since vehicular emissions are regulated by mass output, modern technologies for internal combustion engines favor the generation and formation of UFP because they contribute minimally to the mass output of fine particles (Figure 1). It should come as no surprise that “clean” engines are built to conform to present standards of mass output, despite emitting high numbers of UFP. A standard based on particle number would be more appropriate to reduce UFP emissions. A standard based on particle surface area—as is also proposed—may not be helpful to control UFP because fine particles comprise most of the total particle surface area (Figure 1). In recent measurements made during road-chase studies in Minnesota, UFP concentrations were as high as 1 × 107 particles/cm3 (Kittelson et al. 2001). A short distance from the highways, these high UFP concentrations are lower, but individuals in automobiles on the highways are directly exposed to the high concentrations. Moreover, these UFP are freshly generated, and if results of earlier toxicologic studies with UFP generated from thermodegradation products of polymers are an indication of a general principle of UFP toxicity, freshness and proximity to the source are key requirements for inducing acute adverse effects of UFP. Do UFP emitted from internal combustion engines cause adverse health effects? We still need to know more, but results from our controlled clinical and animal studies using ultrafine elemental carbon particles permit some preliminary conclusions: The high deposition of inhaled UFP (0.007–0.1 μm) in the human respiratory tract as predicted by ICRP (1994) could be confirmed; moreover, deposition was even higher during exercise and in asthmatics. Unlike larger fine particles, UFP seem to escape phagocytosis by alveolar macrophages and are translocated to extrapulmonary organs, as was determined in rodents using ultrafine 13C particles, although such translocation was only minimal with ultrafine iridium particles. Cardiovascular effects in humans and animals and mild pulmonary inflammation in animals were also found following ultrafine carbon particle exposures. Although health effects data and understanding of mechanisms are still limited, there are intriguing data from other disciplines, in particular the field of drug delivery: Intravenously administered UFP were found to cross the blood–brain barrier (Kreuter, 2001), and a transport function of caveolae for macromolecules with molecular radii of several

Ultrafine Particles in the Urban Air: To the Respiratory Tract-And beyond? Is the Central Nervous System Yet Another Target for Ultrafine Particles? (Editorial)

Bioinspired surfaces with special wettability and adhesion have attracted great interest in both fundamental research and industry applications. Various kinds of special wetting surfaces have been constructed by adjusting the topographical structure and chemical composition. Here, recent progress of the artificial superhydrophobic surfaces with high contrast in solid/liquid adhesion has been reviewed, with a focus on the bioinspired construction and applications of one-dimensional (1D) TiO2-based surfaces. In addition, the significant applications related to artificial super-wetting/antiwetting TiO2-based structure surfaces with controllable adhesion are summarized, e.g., self-cleaning, friction reduction, anti-fogging/icing, microfluidic manipulation, fog/water collection, oil/water separation, anti-bioadhesion, and micro-templates for patterning. Finally, the current challenges and future prospects of this renascent and rapidly developing field, especially with regard to 1D TiO2-based surfaces with special wettability and adhesion, are proposed and discussed.

Recent Advances in TiO2-Based Nanostructured Surfaces with Controllable Wettability and Adhesion

Nanosized TiO2-based materials with unique structural and functional properties have already led to breakthroughs in various applications including photocatalysis, adsorption, lithium-ion batteries, etc. In this review, we present the state-of-the-art development of fabrication strategies of titanate/titania nanostructures and their corresponding environmental and energy applications. First, the structural features of titanate and titania and their correlation are explained in great detail. After which, recent research efforts on the development of multi-dimensional titanate materials are summarized. Following that, the applications of titanate/titania nanomaterials in the fields of adsorbents, photocatalysis, lithium-ion batteries, photovoltaics, electrochromic devices, self-cleaning and oil–water separation are reviewed. Finally, the future perspectives for the nanostructured titanate and titania are discussed. Continuous development in this area is essential to endow TiO2-based materials with advanced functionality and improved performance for practical applications.

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Titanate and titania nanostructured materials for environmental and energy applications: a review

Indoor air quality is essential to public health as people spend most of their time indoors Hence, effective indoor air filtering is under heavy demand to deal with this challenge Metal–organic frameworks (MOFs) have been demonstrated as suitable candidates for air pollution control because of their unique properties, such as large surface area and rich functionalities The integration of MOFs into an organic polymer matrix is considered to be an effective method to control air pollution; however, an efficient and low-cost method to fabricate such filters is still lacking Herein, an immersion method was proposed for embedding the homogenous growth of MOFs into nanofibers with a superior capability of wind resistance without film failure The prepared MOF-filter shows effective PM25 and formaldehyde removal The PM25 filtration efficiency increased from 745% to 872% after integrating ZIF-67 nanocrystals into the electrospun PAN nanofibers Moreover, the PM25 filtration efficiency remains at more than 99% during a long-term test over 30 days The ZIF-67@PAN filter also achieves a formaldehyde removal efficiency of 84% This work not only proposes a scalable and low-cost method for fabricating flexible MOF-nanofiber filters but also holds great promise for improving indoor air quality and reducing the associated health risks

Metal–organic framework-based nanofiber filters for effective indoor air quality control

Influence of fiber diameter, filter thickness, and packing density on PM2.5 removal efficiency of electrospun nanofiber air filters for indoor applications

Ye Bian

Papers

Metal–organic framework-based nanofiber filters for effective indoor air quality control

Influence of fiber diameter, filter thickness, and packing density on PM2.5 removal efficiency of electrospun nanofiber air filters for indoor applications

Relationship between pressure drop and face velocity for electrospun nanofiber filters

Experimental and modeling study of pressure drop across electrospun nanofiber air filters

In-situ encapsulation of pseudocapacitive Li2TiSiO5 nanoparticles into fibrous carbon framework for ultrafast and stable lithium storage