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101.
Inorganic halide perovskite (CsPbX3) nanostructures have gained considerable interest in recent years owing to their enhanced stability and optoelectronic applications. Recent developments in the synthesis of nanostructures are reviewed. The impact of the precursor and ligand nature, temperature and growth time on the morphology and shape tuning of CsPbX3 nanostructures is described in relation to their optical properties. The presynthetic and postsynthetic anion exchange strategies to retain pre‐existing crystal phase and shape are discussed in this minireview.  相似文献   
102.
利用AAO模板合成纳米材料   总被引:7,自引:0,他引:7  
利用AAO模板合成纳米材料;氧化铝;纳米结构;综述  相似文献   
103.
The present work reports ferromagnetism by doping magnetic Mn atoms in the diamagnetic ZnO matrix and the ferromagnetism has been extended up to 640 K in nano-grained Zn0.95Mn0.05O samples. The bulk and nano-grained samples were stabilized in hexagonal crystal structure with space group p63mc. The grain size and lattice strain of the samples were estimated from room temperature XRD spectrum. Surface morphology of the samples was examined at room temperature using SEM picture and EDX spectrum. The ferromagnetism of the bulk material shows enhancement in nano-grained samples, which was mainly due to the solution of Mn atoms into the lattice sites of ZnO by mechanical milling. The enhancement of magnetic moment and ferromagnetic ordering temperature with reduction in grain size has been understood in terms of the core-shell structure and existing theoretical models. The present work also demonstrated the role of surface spin disorder on the enhancement of ferromagnetism in Zn0.95Mn0.05O nanograins.  相似文献   
104.
纳米尺度物质的生物效应和安全性   总被引:7,自引:0,他引:7  
纳米尺度的物质包括碳纳米管、纳米二氧化碳、纳米三氧化铁和四氧化三铁等,它们与包括氨基酸在内的生物分子和细胞以及动物整体的相互作用受到广泛关注和研究.结果表明这些纳米材料都能和这些生物成分和生物体相互作用,具有明显的生物效应,能够影响生物分子的结构或构象、细胞的生长,且它们的毒性都较小.但从我们获得的资料看,有些纳米物质对生物的整体特性和人的健康有较重的影响.这是我们应该引起严重注意的.  相似文献   
105.
Carbon mediated catalysis has gained an increasing attention in both areas of nanocatalysis and nanomaterials. The progress in carbon nanomaterials provides many new opportunities to manip-ulate the types and properties of active sites of catalysts through manipulating structures, function-alities and properties of carbon surfaces. The present review focuses on progresses in carbon medi-ated oxidative dehydrogenation reactions of ethylbenzene, propane, and butane. The state-of-the-art of the developments of carbon mediated catalysis is discussed in terms of fundamental studies on adsorption of oxygen and hydrocarbons, reaction mechanism as well as effects of carbon nano-material structures and surface functional groups on the catalytic performance. We highlight the importance and challenges in tuning of the electron density of carbon and oxygen on carbon surfac-es for improving selectivity in oxidative dehydrogenation reactions.  相似文献   
106.
以4种Keggin型多酸作为原料(分别为H3PW12O40·36H2O(简写为PW12a)、H3PMo12O40·34H2O(简写为PMo12a)、H4SiW12O40·35H2O(简写为SiW12a)和H4GeW12O40·40H2O(简写为GeW12a)),采用表面活性剂智能化控制的软化学法制备了相应的4种Keggin型多酸纳米材料,分别为Ag3PW12O40·36H2O(简写为PW12b)、Ag3PMo12O40·34H2O(简写为PMo12b)、Ag4SiW12O40·35H2O(简写为SiW12b)和Ag4GeW12O40·40H2O(简写为GeW12b)。采用IR、UV-Vis、XRD和SEM表征多酸的结构和纳米粒子的形貌。在室内黑暗条件下,100mg样品可在5min内把20mg·L-1的100mL亚甲基蓝(MB)染料溶液脱色,使其变为接近无色,吸附效率最高可达96.3%,吸附效率大小为PMo12b >PW12b >GeW12b >SiW12b。相同条件下,100mg样品使20mg·L-1的100mL罗丹明B(RhB)染料溶液30min内脱色完全,脱色效率最高可达96.1%,吸附效率大小为PW12b >PMo12b >SiW12b >GeW12b。说明该4种多酸纳米材料具有较高的吸附有机染料性能。  相似文献   
107.
Bacterial cellulose (BC) is a natural material produced by Acetobacter xylinum, widely used in wound dressings due to the high water‐holding capacity and great mechanical strength. In this paper, a novel antimicrobial dressing made from BC/methylglyoxal (MGO) composite with a dip‐coating method inspired by naturally antimicrobial Manuka honey is proposed, which to our best knowledge, has not yet to be reported. Characterizations by scanning electron microscope and atomic force microscopy show the interconnected nanostructure of BC and MGO and increase surface roughness of the BC/MGO composite. Thermal analysis indicates high temperature stability of both BC and BC/MGO, while compared with BC, BC/MGO exhibits slightly weaker thermal stability possibly due to reduction of hydrogen bonding and increase of crystallinity. Mechanical test confirms the strong mechanical property of BC and BC/MGO nanocomposite. From the disk diffusion antimicrobial test, the BC/MGO nanocomposite with highest MGO concentration (4%) shows great zone inhibition diameter (around 14.3, 12.3, 17.1, and 15.5 mm against Micrococcus luteus, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli). Compared with other antimicrobial wound dressing composite materials, the proposed BC/MGO nanocomposite has among the greatest antimicrobial property against broad‐spectrum bacteria, making it a promising antimicrobial dressing in chronic wounds care.  相似文献   
108.
DNA nanotechnology enables precise organization of nanoscale objects with extraordinarily structural programmability.Self-assembled DNA nanostructures possess a lot of interesting features,such as designable size and shape,and structural addressability at nanometer scale.Taking advantage of these properties,DNA nanostructures could work as templates or molds for the controllable synthesis of functional nanomaterials,such as organic macromolecules,metallic or inorganic nonmetallic nanomaterials.In this review,we summarize the recent progress in the shape-controllable synthesis of functional nanomaterials on DNA templates.The potential application fields of these nanomaterials are also discussed.  相似文献   
109.
无机纳米材料在能源、生物医学等领域应用非常广泛,过去几十年间关于无机纳米材料合成方法的研究一直受到广泛关注。自然界中普遍存在的生物矿化过程赋予了生物体合成含有特殊结构和功能的无机纳米材料的能力。微生物体系合成的无机纳米材料具有环境友好、成本低廉、生物相容性好等优点,正成为纳米材料科学的一个重要研究领域。我们主要聚焦于微生物体系合成无机纳米材料的机理、影响因素、材料分类及其应用,总结了近年来关于微生物体系合成无机纳米材料的研究历程,并对该领域面临的挑战及未来的发展方向进行了展望。  相似文献   
110.
Fluidinova, a recent start‐up high technology engineering company, has developed and is now commercializing a novel continuous industrial reactor NETmix for the manufacture of high added value products, such as nanomaterials, microemulsions, and pharmaceutical products. Through this technology, Fluidinova, in cooperation with Instituto de Engenharia Biomédica, has developed and patented the industrial process for the synthesis of a new high quality product consisting of hydroxyapatite nanoparticles with extremely high purity and crystallinity to be used as biocompatible nanomaterial for biomedical and pharmaceutical applications, to improve the quality of the already existing hydroxyapatite based medical devices, such as bone grafts, coated implants, and drug delivery systems.  相似文献   
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