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61.
为解决当前陆军演训数据在积累、整合和运用等方面存在的问题,对陆军演训数据分析系统建设进行研 究。在分析演训数据建设现状的基础上,针对演训数据来源、应用定位与流程等方面需求,构建陆军演训数据分析 系统,对系统的功能模块进行设计,并对系统研制中关键技术进行分析,实现演习知识的不断积累。分析结果表明: 该研究能够为后续系统的设计开发提供参考依据,对提高陆军军事训练信息化水平具有现实指导意义。  相似文献   
62.
eFFBD是当前一种主流的功能分析工具,本文研究eFFBD可视化建模工具的设计,使用特定领域语言(DSL)在MetaEdit+平台上进行开发。文中首先对DSL的开发流程和具体步骤进行了总结,然后按照此流程分别设计了eFFBD的核心语言模型,行为模型和具体语法,最后一个功能分析实例演示了该eFFBD建模工具的应用。  相似文献   
63.
64.
Integration of oxides with silicon fuses advanced functional properties with a mature technological platform. In particular, direct EuO/Si contact holds high promise for spintronics but requires single-crystalline epitaxial films with atomically sharp interfaces. The standard approach employing regular 2D superstructures of metal atoms on the Si surface fails to meet the challenge. Here, an alternative route is designed and shown to solve the problem. This route avoids regular templates; the chaotic 2D distribution of metal atoms on the Si surface prevents stabilization of unwanted crystal orientations. Thus, the disordered submonolayer phase at the interface promotes order in oxide/Si coupling, as witnessed by a combination of diffraction techniques and high-resolution electron microscopy. The results not only mark tangible progress in manufacturing EuO/Si contacts but also provide a general framework for monolithic integration of functional oxides with semiconductor substrates.  相似文献   
65.
Plasma technology is an eco-friendly way to modify or fabricate carbon-based materials (CBMs) due to plasmas’ distinctive abilities in tuning the surface physicochemical properties by implanting functional groups or incorporating heteroatoms into the surface without changing the bulk structure. However, the mechanisms of functional groups formation on the carbon surface are still not clearly explained because of the variety of different discharge conditions and the complexity of plasma chemistry. Consequently, this paper contains a comprehensive review of plasma-treated carbon-based materials and their applications in environmental, materials, and energy fields. Plasma-treated CBMs used in these fields have been significantly enhanced in recent years because these related materials possess unique features after plasma treatment, such as higher adsorption capacity, enhanced wettability, improved electrocatalytic activity, etc. Meanwhile, this paper also summarizes possible reaction routes for the generation of functional groups on CBMs. The outlook for future research is summarized, with suggestions that plasma technology research and development shall attempt to achieve precise control of plasmas to synthesize or to modify CBMs at the atomic level.  相似文献   
66.
Densely packed dry‐coated microprojections are shown to deliver vaccines to targeted locations within the skin that are rich in immune cells, thus inducing protective immune responses against a lethal virus challenge. Selectively limiting the antigen coating to the tips of the projections, which penetrate the skin, would significantly reduce the amount of vaccine required in immunization. In this paper a simple technique, dip‐coating the microprojections, is introduced to meet this goal. By increasing the coating solution viscosity, an otherwise strong capillary action is mitigated and the desired controlled coating length on projections is achieved. Following application to the skin, most of the coated vaccine material is rapidly released from the projections (82.6% in mass within 2 min) to the target locations within the skin strata and a potent immune response is induced when a conventional influenza vaccine (Fluvax) is tested in a mouse model. The utility of this coating approach to a variety of molecules representative of vaccines (e.g., chicken egg ovalbumin (OVA) protein, DNA, and fluorescent dyes) is demonstrated. These collective attributes, together with the simplicity of the approach, position the dip‐coating method for practical utility in large vaccination campaigns.  相似文献   
67.
Dynamic core–shell nanoparticles have received increasing attention in recent years. This paper presents a detailed study of Au–Hg nanoalloys, whose composing elements show a large difference in cohesive energy. A simple method to prepare Au@Hg particles with precise control over the composition up to 15 atom% mercury is introduced, based on reacting a citrate stabilized gold sol with elemental mercury. Transmission electron microscopy shows an increase of particle size with increasing mercury content and, together with X‐ray powder diffraction, points towards the presence of a core–shell structure with a gold core surrounded by an Au–Hg solid solution layer. The amalgamation process is described by pseudo‐zero‐order reaction kinetics, which indicates slow dissolution of mercury in water as the rate determining step, followed by fast scavenging by nanoparticles in solution. Once adsorbed at the surface, slow diffusion of Hg into the particle lattice occurs, to a depth of ca. 3 nm, independent of Hg concentration. Discrete dipole approximation calculations relate the UV–vis spectra to the microscopic details of the nanoalloy structure. Segregation energies and metal distribution in the nanoalloys were modeled by density functional theory calculations. The results indicate slow metal interdiffusion at the nanoscale, which has important implications for synthetic methods aimed at core–shell particles.  相似文献   
68.
The oxidative polymerization of aniline hydrochloride derivatives in water at low temperature is studied without lithium chloride. The resulting polymers have high molecular weight but the conductivity of the acid‐doped films is strongly dependent on the alkyl‐substituted chain at the 2‐positions. The root cause of the alkyl‐substitution effects is thoroughly investigated using density functional theory (DFT) methods (B3LYP using 6–1G(d,p) and 6‐311++G(2d,2p) basis sets). Internal structural changes observed on substitution appear to be more significant than a variety of electronic parameters measured using the natural bond orbital (NBO) method. Interplanar angles steadily increase on substitution, whereas ring orbital properties and the amount of ring delocalization remain fairly constant. An investigation into the extent to which lone pair–σ‐orbital overlap is affected by substitution indicates that increasing the steric bulk of the substituent reduces the ability of the lone pair to delocalize into the ring orbitals. However, the amount of overlap between the two is not adversely affected until the dihedral between them is > 30°, a situation that only occurs in i‐propyl and s‐butyl substitution. This finding is completely reflected in the experimental conductivity measurements.  相似文献   
69.
We have studied the defect formation energies of the various native (vacancies, interstitials, and antisites) and Au defects in Hg1−xCdxTe using density functional-based total energy calculations with ultrasoft pseudo-potentials. These studies are important for infrared (IR) detection technology where the device performance can be severely degraded because of defects. To calculate formation energies, we modeled the neutral and charged defects using supercells containing 64 atoms. From the formation energies, we have determined the defect concentrations as a function of stoichiometry and temperature. We find the prevalent neutral defects to be Au at the Hg site (AuHg ), Hg vacancies (VHg ), and Te antisites (TeHg ). We have also explicitly studied charged defects and have found Te Hg 2+ , Au Hg 1− , V Hg 1− , V Hg 2− , and V Te 2+ to have low formation energies. We have identified AuHg to be the prevalent Au defect, having concentrations several orders of magnitude greater than the other Au defects. We find that the charge state of VHg is primarily (1−) or (2−) depending on the electronic chemical potential.  相似文献   
70.
Development of a universal stretchable ionic conductor coating on insulating substrates, irrespective of surface chemistry and substrate shapes, is of immense interest for compliant and integrative large-area electronics but has proved to be extremely challenging. Existing methods relying either on the concurrent deposition of polymerizing precursors or on divided formulation and painting processes both suffer from several limitations in terms of adhesion, dehydration, processability, and surface pre-treatment. Here an ionogel paint that is readily prepared from the concentration-induced autonomous ring-opening polymerization of a natural small molecule—α-thioctic acid (TA) at ambient conditions is reported. The presence of ionic liquid prevents polyTA from further depolymerization via forming COOH···OS hydrogen bonds, resulting in ultra-stretchable ionogels with widely tunable mechanical and conductive properties, self-healability, as well as tissue-like strain adaptability. Moreover, owing to its universal adhesion and adjustable rheology, the ionogel paint can be directly coated on diverse substrates with arbitrary shapes (including porous materials, 3D printed frames, and elastic threads) to render them ionic conductivity. Applications of the ionogel-coated substrates as skin-like highly sensitive and durable large-strain sensors are further demonstrated, suggesting the ionogel paint's great potential in the emerging soft and stretchable electronics.  相似文献   
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