This article features shape‐controlled synthesis of Pd nanostructures. Similar to the Ag system, both the crystallinity of seeds and the growth rates of different crystallographic facets play a vital ...role in determining the final shape of a resultant nanostructure. We specifically discuss how the reduction rate can be controlled to maneuver the crystallinity (i.e., single‐crystal, single twinned, and multiple twinned) of seeds in the nucleation stage. The distribution of multiple twinned and single‐crystal seeds can be further manipulated by employing oxidative etching. As the seed grows into a nanocrystal, the growth rates of different facets (e.g., {111} versus {100}) can be altered with capping agents to control the final shape. The ability to generate Pd nanostructures with a variety of geometrical shapes provides a great opportunity to systematically evaluate their electrical, plasmonic, and catalytic properties, as well as to fully explore their applications.
The shape‐controlled synthesis of Pd nanostructures is featured in this Research News article. A number of useful parameters can be tuned to control the formation of Pd nanostructures with a specific shape in a solution‐phase synthesis are discussed. The ability to control the shape provides an opportunity to systematically evaluate electrical, plasmonic, and catalytic properties as well as to fully explore applications of Pd nanostructures.
Paper and operation, magazine with clinic Xia, Y
Zhonghua er bi yan hou tou jing wai ke za zhi = Chinese journal of otorhinolaryngology head and neck surgery,
2023-Dec-31, Letnik:
58, Številka:
Z1
Journal Article
Large interfacial resistance between electrode and electrolyte limits the development of high-performance all-solid-state batteries. Herein we report a uniform coating of Li7P3S11 solid electrolyte ...on MoS2 to form a MoS2/Li7P3S11 composite electrode for all-solid-state lithium ion batteries. The as-synthesized Li7P3S11 processes a high ionic of 2.0 mS cm−1 at room temperature. Due to homogeneous union and reduced interfacial resistance, the assembled all-solid-state batteries with the MoS2/Li7P3S11 composite electrode exhibit higher reversible capacity of 547.1 mAh g−1 at 0.1 C and better cycling stability than the counterpart based on untreated MoS2. Our study provides a new reference for design/fabrication of advanced electrode materials for high-performance all-solid-state batteries.
•The MoS2/Li7P3S11 composite cathode is prepared by a solution method.•The Li7P3S11 layer on MoS2 particles intimates the interfacial contract.•The high performance is attributed to the interfacial architecture.
Supercapacitor electrode materials must exhibit high specific capacitance and high‐rate charge–discharge ability. The ordered whiskerlike polyaniline (PANI) reported here, which was synthesized in ...situ on the surface of mesoporous carbon by a novel process, is demonstrated to have these properties thanks to its ordered nanometer‐sized “thorns” (see figure) and the V‐shaped nanopores between them.
Locally resonant metamaterials are characterized by bandgaps at wavelengths that are much larger than the lattice size, enabling low-frequency vibration attenuation. Typically, bandgap analyses and ...predictions rely on the assumption of traveling waves in an infinite medium, and do not take advantage of modal representations typically used for the analysis of the dynamic behavior of finite structures. Recently, we developed a method for understanding the locally resonant bandgap in uniform finite metamaterial beams using modal analysis. Here we extend that framework to general locally resonant 1D and 2D metastructures (i.e. locally resonant metamaterial-based finite structures) with specified boundary conditions using a general operator formulation. Using this approach, along with the assumption of an infinite number of resonators tuned to the same frequency, the frequency range of the locally resonant bandgap is easily derived in closed form. Furthermore, the bandgap expression is shown to be the same regardless of the type of vibration problem under consideration, depending only on the added mass ratio and target frequency. For practical designs with a finite number of resonators, it is shown that the number of resonators required for the bandgap to appear increases with increased target frequency, i.e. more resonators are required for higher vibration modes. Additionally, it is observed that there is an optimal, finite number of resonators which gives a bandgap that is wider than the infinite-resonator bandgap, and that the optimal number of resonators increases with target frequency and added mass ratio. As the number of resonators becomes sufficiently large, the bandgap converges to the derived infinite-resonator bandgap. Furthermore, the derived bandgap edge frequencies are shown to agree with results from dispersion analysis using the plane wave expansion method. The model is validated experimentally for a locally resonant cantilever beam under base excitation. Numerical and experimental investigations are performed regarding the effects of mass ratio, non-uniform spacing of resonators, and parameter variations among the resonators.
AIMS: The aim of this study was to characterize anaerobic ammonium oxidation (anammox) community in sediments of the Dongjiang River, a drinking water source of Hong Kong. METHODS AND RESULTS: The ...diversity and distribution of the anammox community were investigated based on a comparative analyses of 16S rRNA and hydrazine oxidation (hzo) genes of anammox bacteria. Candidatus Brocadia and two new anammox bacterial clusters were detected based on phylogenetic analysis of 16S rRNA genes. In contrast, the targeting of hzo genes indicated the presence of only Candidatus Jettenia with four different clusters. It was found that the sequence diversities of hzo genes were higher than those of the 16S rRNA genes. The abundance of anammox bacteria varied significantly among the sediment samples based on qPCR. Pearson correlation analysis indicated that nitrite concentration was the key factor influencing the abundance of anammox bacteria. The redundance analysis (RDA) confirmed that the combination of the contents of nitrite and nitrate, and the ratio of total nitrogen vs total carbon (TN/TC) had significant impact on the anammox bacterial community structure. CONCLUSIONS: The results revealed that the diverse anammox bacteria were present in sediments of the Dongjiang River, and the community structures were associated with varied environmental factors caused by urban pollutant invasion. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report about the distribution of anammox bacterial community in sediments of the Dongjiang River, which provides helpful information of anammox niche specificity and influencing factors in the river ecosystem.
Electrospinning provides a simple and versatile method for generating ultrathin fibers from a rich variety of materials that include polymers, composites, and ceramics. This article presents an ...overview of this technique, with focus on progress achieved in the last three years. After a brief description of the setups for electrospinning, we choose to concentrate on the mechanisms and theoretical models that have been developed for electrospinning, as well as the ability to control the diameter, morphology, composition, secondary structure, and spatial alignment of electrospun nanofibers. In addition, we highlight some potential applications associated with the remarkable features of electrospun nanofibers. Our discussion is concluded with some personal perspectives on the future directions in which this wonderful technique could be pursued.
Current research activities on the electrospinning of nanofibers (see Figure, right) are comprehensively reviewed. After a brief discussion of setups (see Figure, left), the mechanisms and theoretical models for electrospinning are presented, followed by approaches for controlling the diameter, morphology, composition, secondary structure, and spatial alignment. Some potential applications of the remarkable features of electrospun fibers are also highlighted.
The aim of this article is to provide a comprehensive review of current research activities that center on superparamagnetic colloids. We begin with an overview of synthetic strategies that have been ...developed for generating both nanoscale and mesoscale superparamagnetic colloids, with a focus on those systems that can be prepared as monodisperse samples and in relatively large quantities. We then discuss a variety of techniques that have been exploited for modifying surface properties, as well as for controlling the assembly and patterning of these magnetically active colloids. Towards the end, we highlight a range of innovative applications enabled by the unique combination of superparamagnetism and colloidal suspension. We conclude this review article with personal remarks and perspectives on the directions toward which future research in this area might be directed.
Current research activities on superparamagnetic colloids (see figure) are comprehensively reviewed. In this review, three broad aspects are discussed: synthetic strategies for generating superparamagnetic colloids; techniques for modifying their surface property, as well as for controlling the assembly and patterning; and associated innovative applications.
Sphingolipids have garnered attention for their role in insulin resistance and lipotoxic cell death. We have developed transgenic mice inducibly expressing acid ceramidase that display a reduction in ...ceramides in adult mouse tissues. Hepatic overexpression of acid ceramidase prevents hepatic steatosis and prompts improvements in insulin action in liver and adipose tissue upon exposure to high-fat diet. Conversely, overexpression of acid ceramidase within adipose tissue also prevents hepatic steatosis and systemic insulin resistance. Induction of ceramidase activity in either tissue promotes a lowering of hepatic ceramides and reduced activation of the ceramide-activated protein kinase C isoform PKCζ, though the induction of ceramidase activity in the adipocyte prompts more rapid resolution of hepatic steatosis than overexpression of the enzyme directly in the liver. Collectively, our observations suggest the existence of a rapidly acting “cross-talk” between liver and adipose tissue sphingolipids, critically regulating glucose metabolism and hepatic lipid uptake.
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•Ceramides play a causal role in diet-induced NAFLD•Degradation of ceramides in liver results in improved glucose and lipid metabolism•Degradation of ceramide in fat results in improved glucose and lipid metabolism•Ceramide promotes PKCζ activation and CD36-mediated lipid uptake in the liver
Xia et al. reveal a “cross-talk” between the liver and adipose tissue using mice that inducibly express acid ceramidase, which triggers the deacylation of ceramides in these tissues. Decreased ceramide levels result in reduced activation of the ceramide-activated protein kinase C zeta, leading to reduced hepatic steatosis and improved insulin action.
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