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51.
We report the growth mechanism, cathodoluminescence and field emission of dual phase ZnS tetrapod tree‐like heterostructures. This novel heterostructures consist of two phases: zinc blende for the trunk and hexagonal wurtzite for the branch. Direct evidence is presented for the polarity induced growth of tetrapod ZnS trees through high‐resolution electron microscopy study, demonstrating that Zn‐terminated ZnS (111)/(0001) polar surface is chemically active and S‐terminated ( )/(000 ) polar surface is inert in the growth of tetrapod ZnS trees. Two strong UV emissions centered at 3.68 and 3.83 eV have been observed at room temperature, which are attributed to the bandgap emissions from the zinc blende trunk and hexagonal wurtzite branch, indicating that such structures can be used as unique electromechanical and optoelectronic components in potential light sources, laser and light emitting display devices. In addition, the low turn‐on field (2.66 Vµm−1), high field‐enhancement factor (over 2600), large current density (over 30 mAcm−2 at a macroscopic field of 4.33 Vµm−1) and small fluctuation (∼1%) further indicate the availability of ZnS tetrapod tree‐like heterostructures for field emission panel display. This excellent field‐emission property is attributed to the specific crystallographic feature with high crystallinity and cone‐shape patterned branch with nanometer‐sized tips. Such a structure may optimize the FE properties and make a promising field emitter.  相似文献   
52.
Many unique properties arise when the 3D stacking of layered materials is disrupted, originating nanostructures. Stabilization, and further reorganization of these individual layers into complex 3D structures, can be essential to allow these properties to persist in macroscopic systems. It is demonstrated that a simple hydrothermal process, assisted by ionic liquids (ILs), can convert bulk g‐C3N4 into a stable hydrogel. The gelation occurs through delamination of the layered structure, driven by particular interactions between the IL and the carbon nitride sheets, forming an amphiphilic foam‐like network. This study employs spectroscopic and computational tools to unravel the gelation mechanism, and provides a rational approach toward the stabilization of 2D materials in hydrogels. The solution‐processable hydrogels can also be used as building blocks of complex devices. Chemiresistive gas sensors employing g‐C3N4 3D hydrogels exhibit superior response at room temperature, enabling effective gas sensing under low power conditions.  相似文献   
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The incorporation of two or more active components into clay layered structure with uniform distribution is expected to facilitate wider applications of the material. In this study, nanocomposite composed of clay, polyaniline and iron nanoparticles was synthesized by a facile and environmentally friendly strategy for the first time. Local smectite clay from Tunisia was exchanged with Fe3+ then it was subjected to fine grinding with anilinium chloride using mortar grinder and the mixture has been allowed for ageing at ambient air until the change of color to dark green. Both interlayer Fe3+ cations and atmospheric oxygen act as oxidant for aniline polymerization. In addition, the presence of interlayer Fe3+ and Fe2+ cations (the result of the reduction of Fe3+) at the same time favors the formation of iron nanoparticles phase. Electrical and dielectric properties have studied using spectroscopy impedance. The ac conduction shows a regime of constant dc conductivity at low frequencies and a crossover to a frequency-dependent regime of the type AωS at high frequencies. The material shows high dielectric constant, resulting from the presence of iron nanoparticles, indicating its improved ability to store electric energy and to be used as capacitor.  相似文献   
56.
Combining different therapeutic strategies to treat cancer by overcoming limitations of conventional cancer therapies has shown great promise in both fundamental and clinical studies. Herein, by adding 131I when making iodine‐doped CuS nanoparticles, CuS/[131I]I nanoparticles are obtained, which after functionalization with polyethylene glycol (PEG) are used for radiotherapy (RT) and photothermal therapy (PTT), by utilizing their intrinsic high near‐infrared absorbance and the doped 131I‐radioactivity, respectively. The combined RT and PTT based on CuS/[131I]I‐PEG is then conducted, achieving remarkable synergistic therapeutic effects as demonstrated in the treatment of subcutaneous tumors. In the meanwhile, as revealed by bimodal nuclear imaging and computed tomography (CT) imaging, it is found that CuS/[131I]I‐PEG nanoparticles after being injected into primary solid tumors could migrate to and retain in their nearby sentinel lymph nodes. Importantly, the combined RT and PTT applied on those lymph nodes to assist surgical resection of primary tumors results in remarkably inhibited cancer metastasis and greatly prolonged animal survival. In vivo toxicology studies further reveal that our CuS/I‐PEG is not obviously toxic to animals at fourfold of the treatment dose. This work thus demonstrates the potential of combining RT and PTT using a single nanoagent for imaging‐guided treatment of metastatic tumors.  相似文献   
57.
杨菊 《矿冶》2000,9(2):32-36
查明了铁矿物的赋存状态和工艺特性 ,结合生产实践 ,论述了影响铁矿物回收的因素及提高铁回收率的方法和途径。试验结果表明 :弱磁 -螺旋溜槽重选可获得铁精矿品位 66 0 2 %、回收率 90 94%的理想指标 ,比弱磁 -中磁流程铁回收率提高 2 43%。  相似文献   
58.
在磁铁矿精矿粉的烧结配料中加入硼-镁复合添加剂,可显著提高烧结生产效率及烧结矿的质量。经24m 2 烧结机烧结及180m 3 高炉冶炼工业试验表明:采用复合添加剂技术及相应工艺后,烧结机利用系数由1.565t/m 2·h提高到2.093t/m 2 ·h;燃料消耗由92.35kg/t降低到54.04kg/t;高炉利用系数由2.315t/m 3·d 提高到2.955t/m 3·d;入炉焦比由630.43kg/t降低到519.69kg/t。  相似文献   
59.
概述了铁矿粉烧结应用含硼添加剂的现状。叙述了含硼添加剂改善烧结矿质量机理的研究结果。指出应用含硼添加剂应根据烧结原料及工艺条件合理选择含硼物质。  相似文献   
60.
某高岭土细尾矿酸浸除铁的研究   总被引:3,自引:0,他引:3  
研究了用草酸漂白除去高岭土细尾矿中高含量的氧化铁。结果表明 ,草酸能够溶解高岭土中的可浸铁 ,当 p H值低于 1.2 ,浸取温度为 80℃ ,用草酸浸取除铁后 ,高岭土细尾矿的白度达80 % ,达到了工业应用的基本要求。  相似文献   
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