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Qingqing Xiong Gha Young Lee Jianxun Ding Wenliang Li Jinjun Shi 《Nano Research》2018,11(10):5281-5309
As an attractive alternative to plasmid DNA, messenger RNA (mRNA) has recently emerged as a promising class of nucleic acid therapeutics for biomedical applications. Advances in addressing the inherent shortcomings of mRNA and in the development of nanoparticle-based delivery systems have prompted the development and clinical translation of mRNA-based medicines. In this review, we discuss the chemical modification strategies of mRNA to improve its stability, minimize immune responses, and enhance translational efficacy. We also highlight recent progress in nanoparticle-based mRNA delivery. Considerable attention is given to the increasingly widespread applications of mRNA nanomedicine in the biomedical fields of vaccination, protein-replacement therapy, gene editing, and cellular reprogramming and engineering. 相似文献
104.
Shengxian Li Xiangru Feng Jixue Wang Liang He Chunxi Wang Jianxun Ding Xuesi Chen 《Nano Research》2018,11(11):5769-5786
Immunotherapy is a promising strategy to inhibit cancer progression via activation of the immune system. In immunotherapy, adjuvants as immunologic stimulants or delivery systems play a critical role in inducing the antitumor immune response and decreasing the side effects of immune stimulants. Polymer nanoparticles have attracted increasing attention as an indispensable component of immunotherapy, owing to their favorable properties, such as excellent biocompatibility and biodegradability, flexible size, high activity as immune stimulants, large surface area for binding multivalent immune ligands, and high loading capacity for immune-related components. In cancer immunotherapy, polymer nanoparticles can protect cargo from the surrounding milieu, deliver the antigens and immunostimulatory molecules to antigen-presenting cells, or stimulate robust T cell response. This review summarizes the current advancements in polymer nanoparticle adjuvants for cancer immunotherapy and predicts their prospects in fundamental and clinical studies. 相似文献
105.
Uniform and monodisperse ZnSn(OH)6 perfect octahedrons have been synthesized by a facile coprecipitation reaction process. The particle size of the as-prepared ZnSn(OH)6 octahedral structure can be readily controlled by adjusting the reaction temperature (T), and the side length of ZnSn(OH)6 octahedrons was tailored from 3 μm (40°C) to 4 μm (60°C) and 5 μm (80°C). The ethanol sensing properties of ZnSn(OH)6 octahedrons were carefully investigated. The gas sensing experimental data show that the sensor based on ZnSn(OH)6 (40°C) has good selectivity, fast response/recovery time and the highest response (Ra/Rg = 23.8) to 200 ppm ethanol at relatively low optimum operating temperature (200°C) compared to sensors based on ZnSn(OH)6 (60°C) and ZnSn(OH)6 (80°C), which might result from different specific surface areas. The study demonstrated that perfect octahedral ZnSn(OH)6 with controlled crystalline size and desirable sensing performance can be synthesized by a simple fabrication procedure, and the octahedral ZnSn(OH)6 could be a highly promising material for high-performance sensors. 相似文献
106.
采用银镜制备法和激光切割技术获得了纳米银颗粒/聚二甲基硅氧烷剪纸结构薄膜,并系统地研究了薄膜作为柔性应变传感器的力学及压阻特性。将数值模拟与实验相结合,测量了传感薄膜的应变比γ、压阻滞回特性、线性度及压阻敏感性,重点探讨了薄膜制备工艺、结构参数与上述薄膜传感特性的定量关系。结果表明,在给定结构下,结构薄膜整体与结构单元的应变比γ为常数,反映了结构薄膜的变形特性,是理想的力学性能表征参数。菱形剪纸结构薄膜具有量级可达200的大应变比,即在大应变下,材料的实际应变很小。这一特点极大地提升了薄膜的应变测量范围、压阻稳定性、线性度,并保持了合理的压阻灵敏度。 相似文献
107.
In this paper, we consider multiple mobile manipulators grasping a common object in contact with a rigid surface, and propose a new version of adaptive robust control extended to the actuator level for multiple mobile manipulators carrying a common object in a cooperative manner. The proposed controls are robust not only to parametric uncertainties including mass variation and electrical parameters but also to external disturbances. Simulation results are presented to validate that the motion/force tracking errors converge to zero whereas the internal force tracking error remains bounded and can be made arbitrarily small. 相似文献
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109.
Approximate closed‐form expression is derived for the scattering from dipole arrays based on the equivalent circuit theory. Then, a method is proposed for synthesis of dipole arrays to produce desired scattering pattern using genetic algorithm (GA). In the synthesis method, the element positions in an array are considered as the optimization parameter and the derived expression is used to evaluate the fitness function of GA. To assess the validity and efficiency of the proposed method, several linear dipole arrays are designed to obtain scattering pattern with low sidelobe level (SLL). A good agreement between the patterns calculated using the expression and simulated by FEKO validates the accuracy of the presented expression. In addition, the numerical results show that the maximum SLL of the scattering pattern is considerably reduced by optimization. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
110.
Sun-Ju Shen Sheng-Hung Wu Jen-Hao Chi Chen-Chung Lin Jao-Jia Horng Chi-Min Shu 《Simulation Modelling Practice and Theory》2011,19(4):1251-1257
Dicumyl peroxide (DCPO), is produced by cumene hydroperoxide (CHP) process, is utilized as an initiator for polymerization, a prevailing source of free radicals, a hardener, and a linking agent. DCPO has caused several thermal explosion and runaway reaction accidents in reaction and storage zone in Taiwan because of its unstable reactive property. Differential scanning calorimetry (DSC) was used to determine thermokinetic parameters including 700 J g–1 of heat of decomposition (ΔHd), 110 °C of exothermic onset temperature (T0), 130 kJ mol–1 of activation energy (Ea), etc., and to analyze the runaway behavior of DCPO in a reaction and storage zone. To evaluate thermal explosion of DCPO with storage equipment, solid thermal explosion (STE) and liquid thermal explosion (LTE) of thermal safety software (TSS) were applied to simulate storage tank under various environmental temperatures (Te). Te exceeding the T0 of DCPO can be discovered as a liquid thermal explosion situation. DCPO was stored under room temperature without sunshine and was prohibited exceeding 67 °C of self-accelerating decomposition temperature (SADT) for a tank (radius = 1 m and height = 2 m). SADT of DCPO in a box (width, length and height = 1 m, respectively) was determined to be 60 °C. The TSS was employed to simulate the fundamental thermal explosion behavior in a large tank or a drum. Results from curve fitting demonstrated that, even at the earlier stage of the reaction in the experiments, ambient temperature could elicit exothermic reactions of DCPO. To curtail the extent of the risk, relevant hazard information is quite significant and must be provided in the manufacturing process. 相似文献