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961.
Xinghu Fu 《Optik》2011,122(18):1646-1649
Mobile wireless optical communication system was demonstrated experimentally by using a special solid coupling optical taper. The performance of special solid coupling optical taper and the data transmission performance with 240 Mbit/s were investigated on the rectilinear orbit between the mobile terminal and the fixed terminal. The experimental results shown that the scheme used in the mobile wireless optical communication system is reliable and quite simple, which could be widely used in future.  相似文献   
962.
 为研究强激光电离氢原子团簇,在理论上采用1维氢原子团簇的经典粒子动力学模型,结合粒子对(PP)算法及粒子模拟(PIC)方法,采用自行搭建的9节点并行集群系统,利用消息传递接口(MPI)与OpenMP混合编程模型进行了并行数值模拟计算,获得了较为理想的计算加速比。并且引入了弛豫时间参数,有效地处理了粒子间的碰撞过程,在极大简化计算量的同时,保留了物理本质。所得模拟结果与已有的实验结果符合较好,表明该并行计算模型是稳定、可行的。  相似文献   
963.
 以间苯二酚(R)-甲醛(F)为原料,制备了有机气凝胶和碳气凝胶,并对其进行二氧化碳活化。X射线衍射(XRD)测试表明,二氧化碳渗入到碳气凝胶网络结构发生反应,造成(002)峰和(100)峰减弱;扫描电子显微镜(SEM)测试表明,活化没有破坏碳气凝胶的骨架结构,而是增加了大量的nm尺度微孔,从而大大提高了碳气凝胶的比表面积和微孔比例。在1 mol/L KOH电解液中进行了循环伏安和计时电位扫描测试,电极材料电化学性能稳定,具有较好的可逆性,在1 mA/s电流密度下进行充放电测试,得到活化前电极比电容为103 F/g,活化后由于比表面积的增加,比电容达到371 F/g,是一种理想的电化学电极材料。  相似文献   
964.
介绍了掠入射X射线散射法(GXRS法)测量超光滑表面的原理及基于商业用X射线衍射仪改造而成的实验装置。以3片不同粗糙度的硅片作为实验样品,分别应用一级矢量微扰理论和改进的Harvey-Shack理论对其散射分布进行处理,所得结果与原子力显微镜测量结果基本相符。分析了探测器接收狭缝的宽度和入射光发散度对实验结果的影响,随着探测器接收狭缝宽度和入射光发散度的减小,测量误差呈指数迅速减小。在所测量的空间频率范围内,功率谱密度(PSD)函数的误差随频率的增加而减小。  相似文献   
965.
为验证EAST(Experimental and Advanced Superconducting Tokamak)外杜瓦工程设计的可靠性,借助三维设计软件CATIA和有限元分析软件ANSYS,基于协同仿真技术对其进行了研究,结果与EAST运行过程中外杜瓦的实验数据较好的吻合,进行的研究为同类装置外杜瓦的研发提供了有益的参考。  相似文献   
966.
A solvent-free procedure for the synthesis of 3-substituted indole derivates from indoles and nitroalkenes under ultrasound irradiation is described. Control experiments disclosed besides mechanical effects, namely agitation, sonochemical effects are the main forces to drive the reaction. In the method, 2-chloroethanol was used to prepare a wide variety of 3-substituted indole derivates. This procedure only need equimolar amounts of reaction substrates and can be readily scaled up.  相似文献   
967.
Study of proton beam induced welding of multiwall carbon nanotubes (MWCNTs) with ZnO nanowires (NWs) has been carried out by proton (H+) beam irradiation. The samples were irradiated by 70-keV proton (H+) ion beams at different substrate temperatures. The irradiation-induced defects in CNTs and ZnO NWs were greatly reduced at elevated temperature. The crystalline structure of ZnO NWs and MWCNTs were found to remain stable after the irradiation at 700 K. As a preparation step, a coupling of two parallel ZnO NWs with irradiation has also been demonstrated. The welding mechanisms of MWCNTs and ZnO NWs were also been suggested. These two welding processes between same and distinct nanostructures to form homo- and hetero-junctions have provided an opportunity to mass produce interconnecting one-dimensional structures used for the manufacturing of future nanowire-based electronic circuits and devices.  相似文献   
968.
The semiconductor quantum dots (QDs) can be very efficient to tune the response of photocatalyst of TiO2 to visible light. In this study, CdS QDs formed in situ with about 8 nm have been successfully deposited onto the surfaces of TiO2 nanotubes (TNTs) to form TNTs/CdS QDs nanocomposites by use of a simple bifunctional organic linker, thiolactic acid. The diffuse reflectance spectroscopy (DRS) spectra of as prepared samples showed that the absorption edge of the TNTs/CdS composite is extended to visible range, with absorption edge at 530 nm. The photocatalytic activity and stability of TNTs/CdS were also evaluated for the photodegradation of rhodamine B. The results showed that when TNTs/CdS QDs was used, photocatalytic degradation of RhB under visible light irradiation reached 91.6%, higher than 45.4 and 30.5% for P25 and TNTs, respectively. This study indicated that the TNTs/CdS QDs nanocomposites were superior catalysts for photodegradation under visible light irradiation compared with TNTs and P25 samples, which may find wide application as a powerful photocatalyst in environmental field.  相似文献   
969.
We present a systematic experimental investigation on visible light collimation by a nanostructured slit flanked with a pair of periodic array of grooves in gold thin film. A wide variety of aspects are considered, such as the polarization state, the transport path of incident light, the groove-groove spacing, the groove width and depth. Our results clearly show that the relationship between the collimation wavelength and the periodicity of the slit-groove structure accords well with the surface plasmon dispersion model proposed by previous researchers. Furthermore, the surface plasmon wave phase retardation effect induced by the surface structure is also verified via the measurement for samples with different groove widths and depths. These results indicate that the detailed geometry of the groove structure has obvious impacts on the collimation effect and the angular distribution of the diffraction light in the subwavelength plasmonic system.  相似文献   
970.
对不同产地和批次的13个生磁石样品的红外光谱法进行分析,建立磁石的红外光谱指纹图谱,并将炮制品和生品进行分析比较.发现所有生磁石样品指纹图谱的相似度均大于0.97;磁石炮制后相似度和相关系数均降低.傅里叶变换红外光谱指纹图谱可用于商品磁石的分析与品质评价.  相似文献   
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