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71.
Effective messenger RNA (mRNA) transfection in hard‐to‐transfect cells delivered by vectors is a long‐standing challenge. Now it is hypothesized that the high intracellular glutathione level is associated with suppressed mRNA translation. This theory leads to a new design principle of next‐generation mRNA vectors: nanoparticles with glutathione depletion chemistry upregulate mRNA translation and enhance transfection, which is beneficial for mRNA delivery in hard‐to‐transfect cells in vitro and in vivo.  相似文献   
72.
Single atom catalysts (SACs) have attracted much attention in recent years. As an essential group in SACs, M−X−C (X=nonmetallic element) materials have been demonstrated to be efficient in many reactions. However, identifying the active sites on M−X−C, especially under working conditions, is still challenging, which is crucial for chemists to further understand the mechanism underlying the reaction and better design proper SACs for specific reactions. Herein, the types and characterization of M−X−C are comprehensively summarized and discussed in this review. In addition to the basic information above, the challenges and opportunities remaining in this field will be also proposed to present a perspective to the research on the next step.  相似文献   
73.
Global efforts for engineering desired materials which are able to treat the water sources still are ongoing in the bench level methods. Considering adsorbent and photocatalytic materials as the main reliable candidates still are encountering with struggles because of many challenges that restrict their large-scale application. This review comprehensively considered the recent advanced materials water treatment methods which involve to magnetic, activated carbon, carbon nanotubes (CNTs), graphene (G), graphene oxide (GO), (Graphene) quantum dots, carbon nanorods, carbon nano-onions, and reduced graphene oxide (RGO), zeolite, silica and clay-based nanomaterials. The adsorption and photocatalytic properties of these nanomaterials introduced them as highly potent option for heavy metal ions and organic dyes removal and photocatalytic degradation. High specific surface area in conjugation with presenting higher kinetics of adsorption and decomposition are the main characteristics of these materials which make them appropriate to treat wastewater even in ultralow concentration of the pollutants. Considering the mechanistic aspects of the adsorption and photocatalytic decomposition process, challenges and opportunities were other subjects that have been highlighted for the discussed nanomaterials. In term of the adsorption approaches, the mechanism of adsorptions and their influence on the maximum adsorption capacity were discussed and also for photocatalyst approach the radical active spices and their role in kinetic and efficiency of the organic pollutant decomposition were provided a deep discussion.  相似文献   
74.
樊哲  张盛盛  唐家豪  范萍 《应用化学》2020,37(5):489-501
纳米材料因其独特的表面效应、体积效应和量子效应等特点,在化工、生物工程、医学和能源等领域有着广阔的应用。 由简单的低维纳米结构作为主要的构建单元并按照特定的排列方式组装成规整有序的三维结构,即分级纳米结构,已经开展了许多的研究。 本文综述了分级纳米结构的制备方法和微观结构,及其在污水处理、超级电容器、太阳能电池以及光催化等领域的应用。  相似文献   
75.
Recently,the development of new electrode materials for lithium-ion batteries(LIBs)has received intensive attention.As an important family of inorganic materials,mixed Mo-based transition metal oxides system is focused as anode materials.In the present work,a simple route has been adopted for the synthesis of layered-flake-likeβ-SnMo04 Nano-assemblies,which have been explored as potential anode materials for the first time in lithium-ion battery(LIB).Overall,the current reports on metal molybdate as anode materials are still rarely.As the anode material for LIBs,it was observed that the fabricated anode is capable of delivering a steady state capacity of almost 400 mAh/g up to 300 cycles under the influence of200 mA/g current density.Further,the anode material is suitable for use as a rated capacity anode because of its high current density tolerance.The present study can be further extended for the generation of a wide variety of other novel materials for multidisciplinary energy related applications.  相似文献   
76.
The controlled synthesis of multicomponent metal–organic frameworks (MOFs) allows for the precise placement of multiple cooperative functional groups within a framework, leading to emergent synergistic effects. Herein, we demonstrate that turn-on fluorescence sensors can be assembled by combining a fluorophore and a recognition moiety within a complex cavity of a multicomponent MOF. An anthracene-based fluorescent linker and a hemicyanine-containing CN-responsive linker were sequentially installed into the lattice of PCN-700. The selective binding of CN to hemicyanine inhibited the energy transfer between the two moieties, resulting in a fluorescence turn-on effect. Taking advantage of the high tunability of the MOF platform, the ratio between anthracene and the hemicyanine moiety could be fine-tuned in order to maximize the sensitivity of the overall framework. The optimized MOF-sensor had a CN-detection limit of 0.05 μm , which is much lower than traditional CN fluorescent sensors (about 0.2 μm ).  相似文献   
77.
甲壳素基新材料研究进展   总被引:7,自引:0,他引:7  
甲壳素/壳聚糖良好的生物相容性、生物可降解性及独特的生理活性使其成为非常有应用价值的天然高分子材料,当前已成为新材料领域的研究热点.甲壳素/壳聚糖具有良好的可加工性能,可固定贵金属、半导体纳米材料等活性催化物质,同时其本身也具有催化作用,是一类绿色环境友好的高分子催化材料.良好的生物相容性和生物可降解性使甲壳素/壳聚糖...  相似文献   
78.
The encapsulation of iron nanoparticles in protective carbon cages leads to unique hybrid core-shell nanomaterials. Recent literature reports suggest that such nanocomposites can be obtained in a relatively simple process involving the solid state carbothermal reduction of iron oxide nanoparticles. This approach is very attractive because it does not require advanced equipment and consumes less energy in comparison to widely used plasma methods. The presented more-in-depth study shows that the carbothermal approach is sensitive to temperature and the process yield strongly depends on the morphology and crystallinity of the carbon material used as a reductant.  相似文献   
79.
以PEG-2000、柠檬酸和甘氨酸为表面活性剂,采用水热法制备出扁平纳米棒、纳米花和纳米片状的GdF3:Eu3+发光材料,并对其结构和性能进行了表征.XRD结果表明,所得样品均为正交晶系.FESEM照片表明,使用不同表面活性剂所制备的产物形貌不同.研究了以PEG-2000为表面活性剂时反应物浓度对产物形貌的影响,并对其...  相似文献   
80.
近年来,纳米材料在电化学生物传感器领域的研究已成为前沿性的内容.纳米材料具备优异的物理、化学、电催化等性能,加之其量子尺寸效应和表面效应,可将传感器的性能提高到一个新的水平.基于纳米材料的电化学生物传感器呈现出体积更小、速度更快、检测灵敏度更高和可靠性更好等优异性能.该文按照纳米结构的分类,综述了近几年基于以下纳米材料...  相似文献   
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