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21.
Bringing a single still image into reality is a challenging topic in computer animation because the driven and structural information in single still image is inadequate. In this paper, we present an image animating method for enhancing single still image in social media with virtual realistic and animated motions without prior information. We imitate the interaction between the active objects in an image and their neighboring passive objects. The existing actions in the image and the virtual specified force are employed to animate the active objects. Observing that the change between two subsequent motions of the active objects derives a motion tendency, we can calculate a virtual driving force based on the motion tendency. By virtue of the virtual driving force, the stochastic motion texture is used to animate the passive objects. Finally, the convolutional neural network is employed to optimize the virtual motion animations. In this way, the proposed method produces visually natural results while guaranteeing motion harmony between active objects and passive objects. To demonstrate the applicability and rationality of virtual animation driving force, our method generates several animations from still images in Social Media.  相似文献   
22.
Radio-Frequency (RF) energy harvesting must cope with the limited availability and high variability of the energy source. In this paper, the modeling of an RF harvester for ultra low power environments is presented. A mathematical model based on theoretical analysis is developed. The model demonstrates that the maximum transferred power point is located in a three-dimensional space defined by the input capacitance, the output voltage, and the load resistance of the rectifier circuit. Moreover, the mathematical model returns results in substantial agreement with the SPICE simulation results, while guaranteeing a remarkable reduction of the required computation time. Furthermore, the paper reports the implementation of a mixed signal system for the 3-D MPPT, to be embedded in an RF harvester, in a 65 nm CMOS technology. The circuit exhibits a simulated power consumption lower than 100 nW, making this solution suitable for ultra low power harvesting.  相似文献   
23.
The catalytic mechanism and activity of transition metal atom doped C2N (M-C2N, M = Fe, Co, Ni, and Cu) for the oxygen reduction reaction (ORR) are investigated in detail by density functional theory method. All the screened M-C2N are thermodynamically stable based on the binding energy calculations. The adsorption energy results indicate that the adsorption strength of O2 and ORR intermediates are decreased in the order of Fe-C2N ˃ Co-C2N ˃ Ni-C2N ˃ Cu-C2N, in which the adsorption energy values on Cu-C2N are most close to those on the Pt(111). Based on the relative energy diagram of ORR, the energetically favorable pathway on Fe-C2N and Co-C2N is direct 4e mechanism, in which the O–O bond is directly dissociated after the second electron transfer. While for Ni-C2N and Cu-C2N, the most favorable pathway is indirect 4e mechanism, in which the H2O2 is formed as the intermediate product. For all studied M-C2N, the Ni-C2N and Cu-C2N hold better catalytic activity, which could attribute to the contribution of metal atom and part of its activated nitrogen atoms.  相似文献   
24.
Cities worldwide tend to overlook an invaluable asset that lies beneath their surfaces. Most cities and urban regions are unaware of the benefits underground space use has to offer, both for climate inflicted and spatial constraints: In many cities, infrastructure development is being outpaced by population growth. Climate change effects are requiring radical new approaches in terms of coping with for example excessive rainfall. The available space at the surface is rapidly being used up and the biggest danger is that built-up spaces are taking over the public green spaces of cities thereby threatening livability and quality of life. Urban underground space forms a societal asset, which is often unappreciated and underestimated in terms of the role it can play within dynamic city environments and associated challenges.This paper will explore the ways in which urban underground space can be optimally integrated into the dynamic urban context. It also explores the often contradictory functions that make underground space use complicated from a planner’s perspective. The first-come-first-served strategy of underground space use has left many cities wondering how they are going to cope with the self-inflicted “chaos” under the surface. The often mono-functional uses of the underground lead to sub-optimal space use. Most cities and urban regions are unaware of the benefits underground space use has to offer. In guiding the future use of urban underground space, a comprehensive policy framework guiding its development is lacking on which decisions can be based. This often leads to the non-sustainable use of this important asset. It will be argued that both vision and planning are needed to be able to make the best use of this underrated underground real estate.The authors will also debate that just understanding the potential of underground space is not enough. Realising its actual potential and facilitating its development will require a spatial dialogue between many stakeholders, including planners, engineers, developers and public decision makers.  相似文献   
25.
基于委托代理理论给出了双方道德风险组织激励问题的基本分析框架,建立合作与非合作博弈结构下双方道德风险组织激励问题的规划模型。以分析框架与规划模型为基础,引入线性生产与协作生产两种具体的生产方式,全面对比分析了不同博弈结构、不同生产方式下双方道德风险组织激励的均衡努力、最优契约和效用水平,揭示了不同博弈结构、不同生产方式下双方道德风险组织激励问题的特点与规律。  相似文献   
26.
Solid phosphors with uniform morphology can be potentially used in optoelectronic and field-effect transistor applications. In this report, AgxGd1?x(MoO4)2:Eu3+ composites with regular 1-D nanowires assisted by pre-coordination of organic structure (N,N″-dibenzoyl-l-cystine) were designed. The as-derived materials could exhibit striking red emissions by multiple excitations especially the longer wavelength at 466 nm. Furthermore, Ag/Gd ratio was optimized as 1/4. It would be promising to extend the use of ligand-directing agents for the synthesis of a range of novel phosphors.  相似文献   
27.
刘凤翰  李永红  马怀章 《建筑技术》2012,43(12):1094-1097
苏州圆融星座工程体量大,结构复杂,但施工场地局促,施工平面布置及垂直运输协调管理困难。在深基坑工程阶段,通过合理地进行施工平面布置转换,解决了场地紧张的问题。  相似文献   
28.
The potential biological functions of Pleurotus eryngii have long been described in Chinese traditional medicine. However, little is known about the bioactive components of P. eryngii and their functions in liver injury and high-fat induced animal models. The present study thoroughly investigated the comprehensive functions of water-soluble polysaccharidic extract of P. eryngii (PEPE) using in vivo mouse models and in vitro biochemistry tests. PEPE could significantly increase the activities of antioxidant enzymes and effectively remove the free radicals in a liver-injury mouse model. Furthermore, in a high-fat-load mouse model, PEPE not only remarkably decreased the lipid levels of total cholesterol, total triglyceride, and low-density lipoprotein cholesterol, but also resulted in an increase in high-density lipoprotein cholesterol. Histopathological observations indicated that PEPE could effectively prevent excessive lipid formation in liver tissue. Our data suggest that PEPE can be used as a valuable functional food additive for hypolipidemic and hepatoprotective treatments.  相似文献   
29.
Multi-stage countercurrent extraction (MCE) as a novel extraction technique was used to extract antioxidants from Ginkgo biloba leaves. Orthogonal array design (OAD) was employed to optimize the ratio of 60% ethanol to raw material (8–16 mL/g), extraction time (30–60 min) and extraction temperature (60–80 °C) to obtain a high yield of antioxidants from G. biloba leaves by MCE. The optimum conditions were a ratio of 60% ethanol to raw material of 16 mL/g and extraction time of 30 min at 80 °C. Under these conditions, the yields of flavonoids and total phenolics were 1.74% and 2.42%, respectively, and DPPH radicals scavenging activity of the extract was 89.97%. Compared with heat-reflux extraction, MCE had obvious advantages of less extraction time and lower solvent and energy consumption. It may be used as a promising technique for the extraction of bioactive compounds from plant materials.  相似文献   
30.
物象的创造过程是一个原生物象的次生化过程。对原生物象的基本属性的次生转化进行了研究,探讨原生形态向次生形态的转化、原生肌理向次生肌理的转化和原生色彩向次生色彩的转化,试图寻找更有效的途径来优化这一转化过程。  相似文献   
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